A new article provides strong evidence that allergies are much more than just an annoying immune malfunction. They may protect against certain types of cancer.
The article, by researchers Paul Sherman, Erica Holland and Janet Shellman Sherman from Cornell University, suggests that allergy symptoms may protect against cancer by expelling foreign particles, some of which may be carcinogenic or carry absorbed carcinogens, from the organs most likely to come in with contact them. In addition, allergies may serve as early warning devices that let people know when there are substances in the air that should be avoided.
Medical researchers have long suspected an association between allergies and cancer, but extensive study on the subject has yielded mixed, and often contradictory, results. Many studies have found inverse associations between the two, meaning cancer patients tended to have fewer allergies in their medical history. Other studies have found positive associations, and still others found no association at all.
In an attempt to explain these contradictions, the Cornell team reexamined nearly 650 previous studies from the past five decades. They found that inverse allergy-cancer associations are far more common with cancers of organ systems that come in direct contact with matter from the external environment—the mouth and throat, colon and rectum, skin, cervix, pancreas and glial brain cells. Likewise, only allergies associated with tissues that are directly exposed to environmental assaults—eczema, hives, hay fever and animal and food allergies—had inverse relationships to cancers.
Such inverse associations were found to be far less likely for cancers of more isolated tissues like the breast, meningeal brain cells and prostate, as well as for myeloma, non-Hodgkins lymphoma and myelocytic leukemia.
The relationship between asthma and lung cancer, however, is a special case. A majority of the studies that the Cornell team examined found that asthma correlates to higher rates of lung cancer. "Essentially, asthma obstructs clearance of pulmonary mucous, blocking any potentially prophylactic benefit of allergic expulsion," they explain. By contrast, allergies that affect the lungs other than asthma seem to retain the protective effect.
So if allergies are part of the body's defense against foreign particle invaders, is it wise to turn them off with antihistamines and other suppressants? The Cornell team says that studies specifically designed to answer this question are needed.
"We hope that our analyses and arguments will encourage such cost/benefit analyses," they write. "More importantly, we hope that our work will stimulate reconsideration…of the current prevailing view … that allergies are merely disorders of the immune system which, therefore, can be suppressed with impunity."
Thursday, October 30, 2008
Wednesday, October 29, 2008
Global Warming Is Killing Frogs And Salamanders
Frogs and salamanders, those amphibious bellwethers of environmental danger, are being killed in Yellowstone National Park. The predator, Stanford researchers say, is global warming.
Biology graduate student Sarah McMenamin spent three summers in a remote area of the park searching for frogs and salamanders in ponds that had been surveyed 15 years ago. Almost everywhere she looked, she found a catastrophic decrease in the population.
The amphibians need the ponds for their young to hatch, but high temperatures and drought are drying up the water. The frogs and salamanders lay eggs that have a gelatinous outer layer—basically "jelly eggs," McMenamin says—that leaves them completely unsuitable for gestation on land. If the ponds dry up, so do the eggs. "If there isn't any water, then the animals simply don't breed," she said.
Biology Associate Professor Elizabeth Hadly, McMenamin's graduate adviser and co-author of a research paper published this week on the website of the Proceedings of the National Academy of Sciences, has worked in Yellowstone since 1981 and has witnessed the ponds going dry. "They're just blinking off," she said. "It's depressing."
"Precipitous declines of purportedly unthreatened amphibians in the world's oldest nature reserve indicate that the ecological effects of global warming are even more profound and are happening more rapidly than previously anticipated," the researchers wrote.
The disappearing ponds lie in picturesque northern Yellowstone, specifically the lower Lamar Valley, which holds dozens of small fishless ponds where the habitat has been ideal for the breeding and larval development of blotched tiger salamanders, boreal chorus frogs and Colombia spotted frogs. As the world's first national park, it is one of the most environmentally protected areas in the world.
The researchers studied climate and water records going back a century, ranging from handwritten logs of water flow in the Lamar River to satellite imagery, and could find no cause for the drying ponds other than a persistent change in temperature and precipitation. "It's the cumulative effects of climate," Hadly said.
During the summers of 2006 through 2008, McMenamin, wearing hip waders and carrying a dip net, cataloged the amphibian life—or lack thereof—in and around 42 ponds that had been surveyed in 1992-1993. In that earlier survey, involving 46 ponds, 43 supported amphibian populations for at least one of the two years. But in the recent inspection, only 38 of those same ponds even contained water in summer.
In their fieldwork, the researchers were able to visit 31 of the 38 wet ponds (the remainder were off limits, to protect nesting trumpeter swans). Only 21 of them supported amphibian populations for even one of the three years they were checked, 2006-2008. In 15 years the number of ponds with frogs and salamanders had dropped drastically.
"That's when we really got alarmed, because the data just showed such a huge difference," Hadly said.
Historically, the ponds—as small as backyard fish ponds, as large as small lakes—have been recharged during the summer by the groundwater in the soil. But the water table is dropping, the researchers say, as human-induced climate change produces a deadly combination of higher temperatures and less rain and snow. Moreover, the seasonal wetlands near the ponds, usually ideal amphibian habitat, are evaporating earlier in the spring, the result of an earlier snowmelt.
During the course of their study, the researchers witnessed the loss of four amphibian communities because of pond drying. Each event left hundreds of dried tiger salamander corpses behind. The ponds had dried rapidly, over just a few days, too fast for larvae to metamorphose and adults to migrate.
"Everybody can identify with the loss of glaciers, but in Yellowstone the decrease in lakes and ponds and wetlands has been astounding," John Varley, the former chief scientist for Yellowstone, told New West. "What were considered permanent bodies of water, meaning reference was given to them in the 1850s, '60s and '70s, and bestowed with a name as a lake, are now gone. Some wetlands that were considered permanent ponds are no longer there. Some lakes have become ephemeral."
The problem is not going to go away, McMenamin said. "It's extremely depressing and there aren't any evident solutions that come to mind. It's a symptom of a much, much larger problem."
Biology graduate student Sarah McMenamin spent three summers in a remote area of the park searching for frogs and salamanders in ponds that had been surveyed 15 years ago. Almost everywhere she looked, she found a catastrophic decrease in the population.
The amphibians need the ponds for their young to hatch, but high temperatures and drought are drying up the water. The frogs and salamanders lay eggs that have a gelatinous outer layer—basically "jelly eggs," McMenamin says—that leaves them completely unsuitable for gestation on land. If the ponds dry up, so do the eggs. "If there isn't any water, then the animals simply don't breed," she said.
Biology Associate Professor Elizabeth Hadly, McMenamin's graduate adviser and co-author of a research paper published this week on the website of the Proceedings of the National Academy of Sciences, has worked in Yellowstone since 1981 and has witnessed the ponds going dry. "They're just blinking off," she said. "It's depressing."
"Precipitous declines of purportedly unthreatened amphibians in the world's oldest nature reserve indicate that the ecological effects of global warming are even more profound and are happening more rapidly than previously anticipated," the researchers wrote.
The disappearing ponds lie in picturesque northern Yellowstone, specifically the lower Lamar Valley, which holds dozens of small fishless ponds where the habitat has been ideal for the breeding and larval development of blotched tiger salamanders, boreal chorus frogs and Colombia spotted frogs. As the world's first national park, it is one of the most environmentally protected areas in the world.
The researchers studied climate and water records going back a century, ranging from handwritten logs of water flow in the Lamar River to satellite imagery, and could find no cause for the drying ponds other than a persistent change in temperature and precipitation. "It's the cumulative effects of climate," Hadly said.
During the summers of 2006 through 2008, McMenamin, wearing hip waders and carrying a dip net, cataloged the amphibian life—or lack thereof—in and around 42 ponds that had been surveyed in 1992-1993. In that earlier survey, involving 46 ponds, 43 supported amphibian populations for at least one of the two years. But in the recent inspection, only 38 of those same ponds even contained water in summer.
In their fieldwork, the researchers were able to visit 31 of the 38 wet ponds (the remainder were off limits, to protect nesting trumpeter swans). Only 21 of them supported amphibian populations for even one of the three years they were checked, 2006-2008. In 15 years the number of ponds with frogs and salamanders had dropped drastically.
"That's when we really got alarmed, because the data just showed such a huge difference," Hadly said.
Historically, the ponds—as small as backyard fish ponds, as large as small lakes—have been recharged during the summer by the groundwater in the soil. But the water table is dropping, the researchers say, as human-induced climate change produces a deadly combination of higher temperatures and less rain and snow. Moreover, the seasonal wetlands near the ponds, usually ideal amphibian habitat, are evaporating earlier in the spring, the result of an earlier snowmelt.
During the course of their study, the researchers witnessed the loss of four amphibian communities because of pond drying. Each event left hundreds of dried tiger salamander corpses behind. The ponds had dried rapidly, over just a few days, too fast for larvae to metamorphose and adults to migrate.
"Everybody can identify with the loss of glaciers, but in Yellowstone the decrease in lakes and ponds and wetlands has been astounding," John Varley, the former chief scientist for Yellowstone, told New West. "What were considered permanent bodies of water, meaning reference was given to them in the 1850s, '60s and '70s, and bestowed with a name as a lake, are now gone. Some wetlands that were considered permanent ponds are no longer there. Some lakes have become ephemeral."
The problem is not going to go away, McMenamin said. "It's extremely depressing and there aren't any evident solutions that come to mind. It's a symptom of a much, much larger problem."
Tuesday, October 28, 2008
linke bet. stress and acne severity
The largest study ever conducted on acne and stress reveals that teenagers who were under high levels of stress were 23 percent more likely to have increased acne severity, according to researchers from Wake Forest University School of Medicine and colleagues.
"Acne significantly affects physical and psychosocial well-being, so it is important to understand the interplay between the factors that exacerbate acne," said Gil Yosipovitch, M.D., lead author and a professor of dermatology. "Our study suggests a significant association between stress and severity of acne."
The results of the study, which involved 94 adolescents from Singapore, are reported today in Acta Derm Venereol, a Swedish medical journal.
While psychological stress had been identified among many factors that can worsen acne, there has been little research to understand the mechanisms behind this relationship. The current study looked at whether levels of sebum, the oily substance that coats the skin and protects the hair, increase in times of stress and are related to acne severity. Hormone levels, sebum production and bacteria are all known to play major roles in acne.
The study involved secondary school students in Singapore with a mean age of 14.9 years. The students' self-reported stress levels and acne severity were measured at two different times -- just before mid-year exams and during summer break. Students' long-term career prospects are influenced by the results of the examinations and they are known to induce psychological stress.
Stress levels were measured using the Perceived Stress Scale, a 14-item, self-questionnaire that is widely used in stress research. Acne severity was measured using a system that classifies acne based on type and number of lesions. Ninety-two percent of the girls and 95 percent of the boys reported having acne.
Acne is an inflammatory disease of the skin caused by changes in the hair follicle and the sebaceous glands of the skin that produce sebum. The oily substance plugs the pores, resulting in whiteheads or blackheads (acne comedonica) and pimples (acne papulopustulosa).
The researchers suspected that stress increases the quantity of sebum, which leads to increased acne severity. However, the results showed that sebum production didn't differ significantly between the high-stress and low-stress conditions.
The researchers did find that students reporting high stress were 23 percent more likely to have increased severity of acne papulopustulosa. Levels of stress were not linked to severity of acne comedonica.
"Our research suggests that acne severity associated with stress may result from factors others than sebum quantity," said Yosipovitch. "It's possible that inflammation may be involved."
Singapore was selected as the study location because sebum production is known to fluctuate with variations in temperature and humidity. In Singapore's tropical climate, temperature and humidity are consistent throughout the year.
The research was funded by the National Medical Research Council of Singapore.
Co-researchers were Aerlyn Dawn, M.D., from Wake Forest, Mark Tang, M.D., Chee Leok Goh, M.D., and Yiong Hauk Chan, Ph.D., all from National Skin Center and National University of Singapore, and Lim Fong Seng, M.D., from National Healthcare Group Polyclinics, Singapore.
"Acne significantly affects physical and psychosocial well-being, so it is important to understand the interplay between the factors that exacerbate acne," said Gil Yosipovitch, M.D., lead author and a professor of dermatology. "Our study suggests a significant association between stress and severity of acne."
The results of the study, which involved 94 adolescents from Singapore, are reported today in Acta Derm Venereol, a Swedish medical journal.
While psychological stress had been identified among many factors that can worsen acne, there has been little research to understand the mechanisms behind this relationship. The current study looked at whether levels of sebum, the oily substance that coats the skin and protects the hair, increase in times of stress and are related to acne severity. Hormone levels, sebum production and bacteria are all known to play major roles in acne.
The study involved secondary school students in Singapore with a mean age of 14.9 years. The students' self-reported stress levels and acne severity were measured at two different times -- just before mid-year exams and during summer break. Students' long-term career prospects are influenced by the results of the examinations and they are known to induce psychological stress.
Stress levels were measured using the Perceived Stress Scale, a 14-item, self-questionnaire that is widely used in stress research. Acne severity was measured using a system that classifies acne based on type and number of lesions. Ninety-two percent of the girls and 95 percent of the boys reported having acne.
Acne is an inflammatory disease of the skin caused by changes in the hair follicle and the sebaceous glands of the skin that produce sebum. The oily substance plugs the pores, resulting in whiteheads or blackheads (acne comedonica) and pimples (acne papulopustulosa).
The researchers suspected that stress increases the quantity of sebum, which leads to increased acne severity. However, the results showed that sebum production didn't differ significantly between the high-stress and low-stress conditions.
The researchers did find that students reporting high stress were 23 percent more likely to have increased severity of acne papulopustulosa. Levels of stress were not linked to severity of acne comedonica.
"Our research suggests that acne severity associated with stress may result from factors others than sebum quantity," said Yosipovitch. "It's possible that inflammation may be involved."
Singapore was selected as the study location because sebum production is known to fluctuate with variations in temperature and humidity. In Singapore's tropical climate, temperature and humidity are consistent throughout the year.
The research was funded by the National Medical Research Council of Singapore.
Co-researchers were Aerlyn Dawn, M.D., from Wake Forest, Mark Tang, M.D., Chee Leok Goh, M.D., and Yiong Hauk Chan, Ph.D., all from National Skin Center and National University of Singapore, and Lim Fong Seng, M.D., from National Healthcare Group Polyclinics, Singapore.
stress may make you itch
Stress May Make You Itch
Current research suggests that stress may activate immune cells in your skin, resulting in inflammatory skin disease.
Skin provides the first level of defense to infection, serving not only as a physical barrier, but also as a site for white blood cells to attack invading bacteria and viruses. The immune cells in skin can over-react, however, resulting in inflammatory skin diseases such as atopic dermatitis and psoriasis.
Stress can trigger an outbreak in patients suffering from inflammatory skin conditions. This cross talk between stress perception, which involves the brain, and the skin is mediated the through the "brain-skin connection". Yet, little is know about the means by which stress aggravates skin diseases.
Researchers lead by Dr. Petra Arck of Charité, University of Medicine Berlin and McMaster University in Canada, hypothesized that stress could exacerbate skin disease by increasing the number of immune cells in the skin. To test this hypothesis, they exposed mice to sound stress. Dr. Arck's group found that this stress challenge resulted in higher numbers of mature white blood cells in the skin. Furthermore, blocking the function of two proteins that attract immune cells to the skin, LFA-1 and ICAM-1, prevented the stress-induced increase in white blood cells in the skin.
Taken together, these data suggest that stress activates immune cells, which in turn are central in initiating and perpetuating skin diseases. Fostered by the present observation, the goal of future studies in Dr. Arck's group is to prevent stress-triggered outbreaks of skin diseases by recognizing individuals at risk and identifying immune cells suitable to be targeted in therapeutic interventions.
This work was supported by grants from the German Research Foundation and the Charité .
Journal reference:
Joachim RA, Handjiski B, Blois SM, Hagen E, Paus R, Arck PC. Stress-induced neurogenic inflammation in murine skin skews dendritic cells towards maturation and migration: key role of ICAM1/LFA-1 interactions. Am J Pathol, 2008 173:1379-1388
Current research suggests that stress may activate immune cells in your skin, resulting in inflammatory skin disease.
Skin provides the first level of defense to infection, serving not only as a physical barrier, but also as a site for white blood cells to attack invading bacteria and viruses. The immune cells in skin can over-react, however, resulting in inflammatory skin diseases such as atopic dermatitis and psoriasis.
Stress can trigger an outbreak in patients suffering from inflammatory skin conditions. This cross talk between stress perception, which involves the brain, and the skin is mediated the through the "brain-skin connection". Yet, little is know about the means by which stress aggravates skin diseases.
Researchers lead by Dr. Petra Arck of Charité, University of Medicine Berlin and McMaster University in Canada, hypothesized that stress could exacerbate skin disease by increasing the number of immune cells in the skin. To test this hypothesis, they exposed mice to sound stress. Dr. Arck's group found that this stress challenge resulted in higher numbers of mature white blood cells in the skin. Furthermore, blocking the function of two proteins that attract immune cells to the skin, LFA-1 and ICAM-1, prevented the stress-induced increase in white blood cells in the skin.
Taken together, these data suggest that stress activates immune cells, which in turn are central in initiating and perpetuating skin diseases. Fostered by the present observation, the goal of future studies in Dr. Arck's group is to prevent stress-triggered outbreaks of skin diseases by recognizing individuals at risk and identifying immune cells suitable to be targeted in therapeutic interventions.
This work was supported by grants from the German Research Foundation and the Charité .
Journal reference:
Joachim RA, Handjiski B, Blois SM, Hagen E, Paus R, Arck PC. Stress-induced neurogenic inflammation in murine skin skews dendritic cells towards maturation and migration: key role of ICAM1/LFA-1 interactions. Am J Pathol, 2008 173:1379-1388
how plants know to send roots down and leaves up?
VIB researchers at Ghent University discovered how the transport of an important plant hormone is organized in a way that the plant knows in which direction its roots and leaves have to grow. They discovered how the needed transport protein turns up at the underside of plant cells. The discovery helps explain how plants grow, and how they organize themselves in order to grow.
Versatile hormone
It is known for a long time that the plant hormone auxin is transmitted from the top to the bottom of a plant, and that the local concentration of auxin is important for the growth direction of stems, the growth of roots, the sprouting of shoots. To name a few things; auxin is also relevant to, for instance, the ripening of fruit, the clinging of climbers and a series of other processes. Thousands of researchers try to understand the different roles of auxin.
In many instances the distribution of auxin in the plant plays a key role, and thus the transport from cell to cell. At the bottom of plant cells, so-called PIN proteins are located on the cell membrane, helping auxin to flow through to the lower cell. However, no one thoroughly understood why the PIN proteins only showed up at the bottom of a cell.
Endocytosis
An international group of scientists from labs in five countries, headed by Jirí Friml of the VIB-department Plant Systems Biology at Ghent University, revealed a rather unusual mechanism. PIN proteins are made in the protein factories of the cell and are transported all over the cell membrane. Subsequently they are engulfed by the cell membrane, a process called endocytosis.
The invagination closes to a vesicle, disconnects and moves back into the cell. Thus the PIN proteins are recycled and subsequently transported to the bottom of the cell, where they are again incorporated in the cell membrane. It is unclear why plants use such a complex mechanism, but a plausible explanation is this mechanism enables a quick reaction when plant cells feel a change of direction of gravity, giving them a new ‘underside’.
Gene technology
To see the path of the protein, the researchers used gene technology to make cells in which the PIN protein was linked to fluorescent proteins. (This technology was rewarded with the Nobel Prize 2008 for chemistry.) Subsequently they produced cells in which the endocytosis was disrupted in two different ways. The PIN proteins showed up all over the cell membrane. When the researchers proceeded from single cells to plant embryos, the embryos developed deformations, because the pattern of auxin concentrations in the embryo was distorted. When these plants with disrupted endocytosis grew further, roots developed where the first leaflet should have been
Versatile hormone
It is known for a long time that the plant hormone auxin is transmitted from the top to the bottom of a plant, and that the local concentration of auxin is important for the growth direction of stems, the growth of roots, the sprouting of shoots. To name a few things; auxin is also relevant to, for instance, the ripening of fruit, the clinging of climbers and a series of other processes. Thousands of researchers try to understand the different roles of auxin.
In many instances the distribution of auxin in the plant plays a key role, and thus the transport from cell to cell. At the bottom of plant cells, so-called PIN proteins are located on the cell membrane, helping auxin to flow through to the lower cell. However, no one thoroughly understood why the PIN proteins only showed up at the bottom of a cell.
Endocytosis
An international group of scientists from labs in five countries, headed by Jirí Friml of the VIB-department Plant Systems Biology at Ghent University, revealed a rather unusual mechanism. PIN proteins are made in the protein factories of the cell and are transported all over the cell membrane. Subsequently they are engulfed by the cell membrane, a process called endocytosis.
The invagination closes to a vesicle, disconnects and moves back into the cell. Thus the PIN proteins are recycled and subsequently transported to the bottom of the cell, where they are again incorporated in the cell membrane. It is unclear why plants use such a complex mechanism, but a plausible explanation is this mechanism enables a quick reaction when plant cells feel a change of direction of gravity, giving them a new ‘underside’.
Gene technology
To see the path of the protein, the researchers used gene technology to make cells in which the PIN protein was linked to fluorescent proteins. (This technology was rewarded with the Nobel Prize 2008 for chemistry.) Subsequently they produced cells in which the endocytosis was disrupted in two different ways. The PIN proteins showed up all over the cell membrane. When the researchers proceeded from single cells to plant embryos, the embryos developed deformations, because the pattern of auxin concentrations in the embryo was distorted. When these plants with disrupted endocytosis grew further, roots developed where the first leaflet should have been
new strategy in treatment of common infection
Researchers at Georgetown University Medical Center (GUMC)
have successfully tested a genetic strategy designed to improve treatment of human infections caused by the yeast Candida albicans, ranging from diaper rash, vaginitis, oral infections (or thrush which is common in HIV/AIDS patients), as well as invasive, blood-borne and life-threatening diseases.
Their findings confirm that inhibiting a key protein could provide a new drug target against the yeast, which inhabits the mucous membranes of most humans. The research was presented today at the 48th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy/46th Annual Meeting of the Infectious Diseases Society of America (ICAAC/IDSA) in Washington, DC.
"This is a genetically intelligent approach to target identification and drug design," says the study's lead author, Richard Calderone, PhD, professor and chair of the department of microbiology and immunology and co-director of the PhD program in the global infectious disease program at GUMC.
"Candida infections are often treatable, however, in patients that are immunocompromised following cancer chemotherapy, bone marrow transplantation, or surgery, diagnosis is often delayed, postponing therapy," he says. "Also when drug-resistant yeast pathogens cause the infection, clinical management of the patient becomes a problem."
Candida invasive, blood-borne infections are the fourth most common hospital-acquired infection in the United States, costing the healthcare system about $1.8 billion each year, Calderone says.
"More drug resistance is being seen clinically, so there is significant room for improvement in the therapies used today," he says
This study continues research in which Calderone and his colleagues identified a protein, the product of the Ssk1 gene that Candida needs to infect its host. To date, this protein has not been found in humans or in animals, which means it could be "targeted" with a novel drug without producing toxicity because such an agent should only attack the fungus.
The researchers found that if the Ssk1 gene is deleted from Candida albicans, the "triazole" drugs that are now used to treat these diseases are much more effective in the laboratory. "This allows the triazole drugs to do their job," Calderone says. "We propose that this finding might lead to other, possibly more effective, treatment options."
In this study, the researchers used a gene microarray analysis to further understand what knocking out the Ssk1 gene does to the organism, and they discovered that the gene is critical to the pathogenic nature of the fungi.
What this means is that an Ssk1 inhibitor might work in synergy with a triazole or perhaps as an effective stand-alone drug to treat Candida infections, the researchers say. If it works in Candida, it may have broader activity in other pathogens because Ssk1p is found in other fungi.
"Using the genome of the organism to find genes to target is a logical approach to drug design," he says. The researchers are now working with other groups to find the right agent to target the Ssk1protein.
Neeraj Chauhan, PhD, assistant research professor in the department of microbiology and immunology at GUMC, is co-author on the study. The authors report no disclosures. This research was funded by the National Institutes of Allergy & Infectious Diseases of the NIH.
have successfully tested a genetic strategy designed to improve treatment of human infections caused by the yeast Candida albicans, ranging from diaper rash, vaginitis, oral infections (or thrush which is common in HIV/AIDS patients), as well as invasive, blood-borne and life-threatening diseases.
Their findings confirm that inhibiting a key protein could provide a new drug target against the yeast, which inhabits the mucous membranes of most humans. The research was presented today at the 48th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy/46th Annual Meeting of the Infectious Diseases Society of America (ICAAC/IDSA) in Washington, DC.
"This is a genetically intelligent approach to target identification and drug design," says the study's lead author, Richard Calderone, PhD, professor and chair of the department of microbiology and immunology and co-director of the PhD program in the global infectious disease program at GUMC.
"Candida infections are often treatable, however, in patients that are immunocompromised following cancer chemotherapy, bone marrow transplantation, or surgery, diagnosis is often delayed, postponing therapy," he says. "Also when drug-resistant yeast pathogens cause the infection, clinical management of the patient becomes a problem."
Candida invasive, blood-borne infections are the fourth most common hospital-acquired infection in the United States, costing the healthcare system about $1.8 billion each year, Calderone says.
"More drug resistance is being seen clinically, so there is significant room for improvement in the therapies used today," he says
This study continues research in which Calderone and his colleagues identified a protein, the product of the Ssk1 gene that Candida needs to infect its host. To date, this protein has not been found in humans or in animals, which means it could be "targeted" with a novel drug without producing toxicity because such an agent should only attack the fungus.
The researchers found that if the Ssk1 gene is deleted from Candida albicans, the "triazole" drugs that are now used to treat these diseases are much more effective in the laboratory. "This allows the triazole drugs to do their job," Calderone says. "We propose that this finding might lead to other, possibly more effective, treatment options."
In this study, the researchers used a gene microarray analysis to further understand what knocking out the Ssk1 gene does to the organism, and they discovered that the gene is critical to the pathogenic nature of the fungi.
What this means is that an Ssk1 inhibitor might work in synergy with a triazole or perhaps as an effective stand-alone drug to treat Candida infections, the researchers say. If it works in Candida, it may have broader activity in other pathogens because Ssk1p is found in other fungi.
"Using the genome of the organism to find genes to target is a logical approach to drug design," he says. The researchers are now working with other groups to find the right agent to target the Ssk1protein.
Neeraj Chauhan, PhD, assistant research professor in the department of microbiology and immunology at GUMC, is co-author on the study. The authors report no disclosures. This research was funded by the National Institutes of Allergy & Infectious Diseases of the NIH.
Monday, October 27, 2008
cancer
Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells.
Carcinoma; Malignant tumor
Causes
Cells are the building blocks of living things. Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't need them. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly. It can also occur when cells “forget” how to die.
There are many different kinds of cancers. Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.
There are many causes of cancers, including:
Benzene and other chemicals
Certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
Certain viruses
Radiation
Sunlight
Tobacco
However, the cause of many cancers remains unknown.
The most common cause of cancer-related death is lung cancer.
The three most common cancers in men in the United States are:
Prostate cancer
Lung cancer
Colon cancer
In women in the U.S., the three most common cancers are:
Breast cancer
Colon cancer
Lung cancer
Some cancers are more common in certain parts of the world. For example, in Japan, there are many cases of gastric cancer, but in the U.S. this type of cancer is pretty rare. Differences in diet may play a role.
Some other types of cancers include:
Brain cancer
Cervical cancer
Hodgkin's lymphoma
Kidney cancer
Leukemia
Liver cancer
Non-Hodgkin's lymphoma
Ovarian cancer
Skin cancer
Testicular cancer
Thyroid cancer
Uterine cancer
Symptoms
Symptoms of cancer depend on the type and location of the tumor. For example, lung cancer can cause coughing, shortness of breath, or chest pain. Colon cancer often causes diarrhea, constipation, and blood in the stool.
Some cancers may not have any symptoms at all. In certain cancers, such as gallbladder cancer, symptoms often do not start until the disease has reached an advanced stage.
The following symptoms can occur with most cancers:
Chills
Fatigue
Fever
Loss of appetite
Malaise
Night sweats
Weight loss
Exams and Tests
Like symptoms, the signs of cancer vary based on the type and location of the tumor. Common tests include the following:
Biopsy of the tumor
Blood chemistries
Bone marrow biopsy (for lymphoma or leukemia)
Chest x-ray
Complete blood count (CBC)
CT scan
Most cancers are diagnosed by biopsy. Depending on the location of the tumor, the biopsy may be a simple procedure or a serious operation. Most patients with cancer have CT scans to determine the exact location and size of the tumor or tumors.
A cancer diagnosis is difficult to cope with. It is important, however, that you discuss the type, size, and location of the cancer with your doctor when you are diagnosed. You also will want to ask about treatment options, along with their benefits and risks.
It's a good idea to have someone with you at the doctor's office to help you get through the diagnosis. If you have trouble asking questions after hearing about your diagnosis, the person you bring with you can ask them for you.
Treatment
Treatment also varies based on the type of cancer and its stage. The stage of a cancer refers to how much it has grown and whether the tumor has spread from its original location.
If the cancer is confined to one location and has not spread, the most common goals for treatment are surgery and cure. This is often the case with skin cancers, as well as cancers of the lung, breast, and colon.
If the tumor has spread to local lymph nodes only, sometimes these can also be removed.
If surgery cannot remove all of the cancer, the options for treatment include radiation, chemotherapy, or both. Some cancers require a combination of surgery, radiation, and chemotherapy.
Although treatment for cancer can be difficult, there are many ways to keep up your strength.
If you have radiation treatment, know that:
Radiation treatment is painless.
Treatment is usually scheduled every weekday.
You should allow 30 minutes for each treatment session, although the treatment itself usually takes only a few minutes.
You should get plenty of rest and eat a well-balanced diet during the course of your radiation therapy.
Skin in the treated area may become sensitive and easily irritated.
Side effects of radiation treatment are usually temporary. They vary depending on the area of the body that is being treated.
If you are going through chemotherapy, you should eat right. Chemotherapy causes your immune system to weaken, so you should avoid people with colds or the flu. You should also get plenty of rest, and don't feel as though you have to accomplish tasks all at once.
It will help you to talk with family, friends, or a support group about your feelings. Work with your health care providers throughout your treatment. Helping yourself can make you feel more in control.
Support Groups
A cancer diagnosis often causes a lot of anxiety and can affect your entire quality of life. Several support groups for cancer patients can help you cope.
Outlook (Prognosis)
The outlook depends on the type of cancer. Even among people with one type of cancer, the outcome varies depending on the stage of the tumor when they are diagnosed.
Some cancers can be cured. Some cancers that are not curable can still be treated well. And some patients can live for many years with their cancer. Other tumors are quickly life-threatening.
Possible Complications
One complication is that the cancer may spread. Other complications vary with the type and stage of the tumor.
When to Contact a Medical Professional
Contact your health care provider if you develop symptoms of cancer.
Prevention
One of the best ways to prevent cancer is to not smoke or chew tobacco. Many cancers can be prevented by avoiding risk factors such as excessive exposure to sunlight and heavy drinking.
Cancer screenings, such as mammography and breast examination for breast cancer and colonoscopy for colon cancer, may help catch these cancers at their early stages when they are most treatable. Some people at high risk for developing certain cancers can take medication to reduce their risk.
More Information on This Topic
News & Features
Review Date: 8/2/2008Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch). A.D.A.M. CopyrightThe information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2008 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
Carcinoma; Malignant tumor
Causes
Cells are the building blocks of living things. Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't need them. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly. It can also occur when cells “forget” how to die.
There are many different kinds of cancers. Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.
There are many causes of cancers, including:
Benzene and other chemicals
Certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
Certain viruses
Radiation
Sunlight
Tobacco
However, the cause of many cancers remains unknown.
The most common cause of cancer-related death is lung cancer.
The three most common cancers in men in the United States are:
Prostate cancer
Lung cancer
Colon cancer
In women in the U.S., the three most common cancers are:
Breast cancer
Colon cancer
Lung cancer
Some cancers are more common in certain parts of the world. For example, in Japan, there are many cases of gastric cancer, but in the U.S. this type of cancer is pretty rare. Differences in diet may play a role.
Some other types of cancers include:
Brain cancer
Cervical cancer
Hodgkin's lymphoma
Kidney cancer
Leukemia
Liver cancer
Non-Hodgkin's lymphoma
Ovarian cancer
Skin cancer
Testicular cancer
Thyroid cancer
Uterine cancer
Symptoms
Symptoms of cancer depend on the type and location of the tumor. For example, lung cancer can cause coughing, shortness of breath, or chest pain. Colon cancer often causes diarrhea, constipation, and blood in the stool.
Some cancers may not have any symptoms at all. In certain cancers, such as gallbladder cancer, symptoms often do not start until the disease has reached an advanced stage.
The following symptoms can occur with most cancers:
Chills
Fatigue
Fever
Loss of appetite
Malaise
Night sweats
Weight loss
Exams and Tests
Like symptoms, the signs of cancer vary based on the type and location of the tumor. Common tests include the following:
Biopsy of the tumor
Blood chemistries
Bone marrow biopsy (for lymphoma or leukemia)
Chest x-ray
Complete blood count (CBC)
CT scan
Most cancers are diagnosed by biopsy. Depending on the location of the tumor, the biopsy may be a simple procedure or a serious operation. Most patients with cancer have CT scans to determine the exact location and size of the tumor or tumors.
A cancer diagnosis is difficult to cope with. It is important, however, that you discuss the type, size, and location of the cancer with your doctor when you are diagnosed. You also will want to ask about treatment options, along with their benefits and risks.
It's a good idea to have someone with you at the doctor's office to help you get through the diagnosis. If you have trouble asking questions after hearing about your diagnosis, the person you bring with you can ask them for you.
Treatment
Treatment also varies based on the type of cancer and its stage. The stage of a cancer refers to how much it has grown and whether the tumor has spread from its original location.
If the cancer is confined to one location and has not spread, the most common goals for treatment are surgery and cure. This is often the case with skin cancers, as well as cancers of the lung, breast, and colon.
If the tumor has spread to local lymph nodes only, sometimes these can also be removed.
If surgery cannot remove all of the cancer, the options for treatment include radiation, chemotherapy, or both. Some cancers require a combination of surgery, radiation, and chemotherapy.
Although treatment for cancer can be difficult, there are many ways to keep up your strength.
If you have radiation treatment, know that:
Radiation treatment is painless.
Treatment is usually scheduled every weekday.
You should allow 30 minutes for each treatment session, although the treatment itself usually takes only a few minutes.
You should get plenty of rest and eat a well-balanced diet during the course of your radiation therapy.
Skin in the treated area may become sensitive and easily irritated.
Side effects of radiation treatment are usually temporary. They vary depending on the area of the body that is being treated.
If you are going through chemotherapy, you should eat right. Chemotherapy causes your immune system to weaken, so you should avoid people with colds or the flu. You should also get plenty of rest, and don't feel as though you have to accomplish tasks all at once.
It will help you to talk with family, friends, or a support group about your feelings. Work with your health care providers throughout your treatment. Helping yourself can make you feel more in control.
Support Groups
A cancer diagnosis often causes a lot of anxiety and can affect your entire quality of life. Several support groups for cancer patients can help you cope.
Outlook (Prognosis)
The outlook depends on the type of cancer. Even among people with one type of cancer, the outcome varies depending on the stage of the tumor when they are diagnosed.
Some cancers can be cured. Some cancers that are not curable can still be treated well. And some patients can live for many years with their cancer. Other tumors are quickly life-threatening.
Possible Complications
One complication is that the cancer may spread. Other complications vary with the type and stage of the tumor.
When to Contact a Medical Professional
Contact your health care provider if you develop symptoms of cancer.
Prevention
One of the best ways to prevent cancer is to not smoke or chew tobacco. Many cancers can be prevented by avoiding risk factors such as excessive exposure to sunlight and heavy drinking.
Cancer screenings, such as mammography and breast examination for breast cancer and colonoscopy for colon cancer, may help catch these cancers at their early stages when they are most treatable. Some people at high risk for developing certain cancers can take medication to reduce their risk.
More Information on This Topic
News & Features
Review Date: 8/2/2008Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch). A.D.A.M. CopyrightThe information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2008 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
asthma
Asthma is an inflammatory disorder of the airways, which causes attacks of wheezing, shortness of breath, chest tightness, and coughing.
Asthma is caused by inflammation in the airways. When an asthma attack occurs, the muscles surrounding the airways become tight and the lining of the air passages swell. This reduces the amount of air that can pass by, and can lead to wheezing sounds.
Most people with asthma have wheezing attacks separated by symptom-free periods. Some patients have long-term shortness of breath with episodes of increased shortness of breath. Still, in others, a cough may be the main symptom. Asthma attacks can last minutes to days and can become dangerous if the airflow becomes severely restricted.
In sensitive individuals, asthma symptoms can be triggered by breathing in allergy-causing substances (called allergens or triggers). Triggers include pet dander, dust mites, cockroach allergens, molds, or pollens. Asthma symptoms can also be triggered by respiratory infections, exercise, cold air, tobacco smoke and other pollutants, stress, food, or drug allergies. Aspirin and other non-steroidal anti-inflammatory medications (NSAIDS) provoke asthma in some patients.
Approximately 20.5 million Americans currently have asthma. Many people with asthma have an individual or family history of allergies, such as hay fever (allergic rhinitis) or eczema. Others have no history of allergies.
exams and tests
persistent asthma. Common allergens include pet dander, dust mites, cockroach allergens, molds, and pollens. Common respiratory irritants include tobacco smoke, pollution, and fumes from burning wood or gas.
The doctor will use a stethoscope to listen to the lungs. Asthma-related sounds may be heard. However, lung sounds are usually normal between asthma episodes.
Tests may include:
Lung function tests
Peak flow measurements
Chest x-ray
Blood tests, including eosinophil count (a type of white blood cell)
Arterial blood gas In-Depth Diagnosis »
TopSymptoms
Wheezing
Usually begins suddenly
Comes in episodes
May be worse at night or in early morning
Gets worse with cold aira, exercise, and heartburn (reflux)
May go away on its own
Is relieved by bronchodilators (drugs that open the airways)
Cough with or without sputum (phlegm) production
Shortness of breath that gets worse with exercise or activity
Intercostal retractions (pulling of the skin between the ribs when breathing)
Emergency symptoms:
Extreme difficulty breathing
Bluish color to the lips and face
Severe anxiety due to shortness of breath
Rapid pulse
Sweating
Decreased level of alertness, such as severe drowsiness or confusion, during an asthma attack
Additional symptoms that may be associated with this disease:
Nasal flaring
Chest pain
Tightness in the chest
Abnormal breathing pattern --breathing out takes more than twice as long as breathing in
Breathing temporarily stops
The stress caused by illness can often be helped by joining a support group, where members share common experiences and problems. See asthma and allergy - support group.
Treatment is aimed at avoiding known allergens and respiratory irritants and controlling symptoms and airway inflammation through medication.
There are two basic kinds of medication for the treatment of asthma:
Long-term control medications are used on a regular basis to prevent attacks, not for treatment during an attack. Types include:
Inhaled steroids (such as Azmacort, Vanceril, AeroBid, Flovent) prevent inflammation
Leukotriene inhibitors (such as Singulair and Accolate)
Anti-IgE therapy (Xolair), a medicine given by injection to patients with more severe asthma
Long-acting bronchodilators (such as Serevent) help open airways
Cromolyn sodium (Intal) or nedocromil sodium
Aminophylline or theophylline (not used as frequently as in the past)
Sometimes a combination of steroids and bronchodilators are used, using either separate inhalers or a single inhaler (such as Advair Diskus).
Quick relief, or rescue, medications are used to relieve symptoms during an attack. These include:
Short-acting bronchodilators (inhalers), such as Proventil, Ventolin, Xopenex, and others.
Corticosteroids, such as prednisone or methylprednisolone) given by mouth or into a vein
Persons with mild asthma (infrequent attacks) may use quick relief medication as needed. Those with persistent asthma should take control medications on a regular basis to prevent symptoms. A severe asthma attack requires a medical evaluation and may require a hospital stay, oxygen, and intravenous medications.
A peak flow meter, a simple device to measure lung volume, can be used at home to help you "see an attack coming" and take the appropriate action, sometimes even before any symptoms appear. If you are not monitoring asthma on a regular basis, an attack can take you by surprise.
Peak flow measurements can help show when medication is needed, or other action needs to be taken. Peak flow values of 50-80% of an individual’s personal best results indicate a moderate asthma attack, while values below 50% indicate a severe attack.There is no cure for asthma, though symptoms sometimes decrease over time. With proper self management and medical treatment, most people with asthma can lead normal lives.
Possible Complications
Respiratory fatigue
Side effects of asthma medications
Pneumothorax
Death
When to Contact a Medical Professional
Call for an appointment with your health care provider if you or your child experience mild asthma symptoms (to discuss treatment options).
Call your health care provider (or go to the emergency room) for moderate shortness of breath (shortness of breath with talking, peak flow 50-80% of personal best), if symptoms worsen or do not improve with treatment, or an attack requires more medication than recommended in the prescription.
Go to the emergency room for severe shortness of breath (shortness of breath at rest, peak flow less than 50% of personal best), if drowsiness or confusion develops, or for severe chest pain.
Prevention
Asthma symptoms can be substantially reduced by avoiding known allergens and respiratory irritants. If someone with asthma is sensitive to dust mites, exposure can be reduced by encasing mattresses and pillows in allergen-impermeable covers, removing carpets from bedrooms, and by vacuuming regularly. Exposure to dust mites and mold can be reduced by lowering indoor humidity.
If a person is allergic to an animal that cannot be removed from the home, the animal should be kept out of the patient's bedroom. Filtering material can be placed over the heating outlets to trap animal dander. Exposure to cigarette smoke, air pollution, industrial dusts, and irritating fumes should also be avoided.
Allergy desensitization may be helpful in reducing asthma symptoms and medication use, but the size of the benefit compared with other treatments is not known.
Guidelines for the Diagnosis and Management of Asthma -- Update on Selected Topics 2002. Bethesda, MD. 2003 June. National Asthma
Asthma is caused by inflammation in the airways. When an asthma attack occurs, the muscles surrounding the airways become tight and the lining of the air passages swell. This reduces the amount of air that can pass by, and can lead to wheezing sounds.
Most people with asthma have wheezing attacks separated by symptom-free periods. Some patients have long-term shortness of breath with episodes of increased shortness of breath. Still, in others, a cough may be the main symptom. Asthma attacks can last minutes to days and can become dangerous if the airflow becomes severely restricted.
In sensitive individuals, asthma symptoms can be triggered by breathing in allergy-causing substances (called allergens or triggers). Triggers include pet dander, dust mites, cockroach allergens, molds, or pollens. Asthma symptoms can also be triggered by respiratory infections, exercise, cold air, tobacco smoke and other pollutants, stress, food, or drug allergies. Aspirin and other non-steroidal anti-inflammatory medications (NSAIDS) provoke asthma in some patients.
Approximately 20.5 million Americans currently have asthma. Many people with asthma have an individual or family history of allergies, such as hay fever (allergic rhinitis) or eczema. Others have no history of allergies.
exams and tests
persistent asthma. Common allergens include pet dander, dust mites, cockroach allergens, molds, and pollens. Common respiratory irritants include tobacco smoke, pollution, and fumes from burning wood or gas.
The doctor will use a stethoscope to listen to the lungs. Asthma-related sounds may be heard. However, lung sounds are usually normal between asthma episodes.
Tests may include:
Lung function tests
Peak flow measurements
Chest x-ray
Blood tests, including eosinophil count (a type of white blood cell)
Arterial blood gas In-Depth Diagnosis »
TopSymptoms
Wheezing
Usually begins suddenly
Comes in episodes
May be worse at night or in early morning
Gets worse with cold aira, exercise, and heartburn (reflux)
May go away on its own
Is relieved by bronchodilators (drugs that open the airways)
Cough with or without sputum (phlegm) production
Shortness of breath that gets worse with exercise or activity
Intercostal retractions (pulling of the skin between the ribs when breathing)
Emergency symptoms:
Extreme difficulty breathing
Bluish color to the lips and face
Severe anxiety due to shortness of breath
Rapid pulse
Sweating
Decreased level of alertness, such as severe drowsiness or confusion, during an asthma attack
Additional symptoms that may be associated with this disease:
Nasal flaring
Chest pain
Tightness in the chest
Abnormal breathing pattern --breathing out takes more than twice as long as breathing in
Breathing temporarily stops
The stress caused by illness can often be helped by joining a support group, where members share common experiences and problems. See asthma and allergy - support group.
Treatment is aimed at avoiding known allergens and respiratory irritants and controlling symptoms and airway inflammation through medication.
There are two basic kinds of medication for the treatment of asthma:
Long-term control medications are used on a regular basis to prevent attacks, not for treatment during an attack. Types include:
Inhaled steroids (such as Azmacort, Vanceril, AeroBid, Flovent) prevent inflammation
Leukotriene inhibitors (such as Singulair and Accolate)
Anti-IgE therapy (Xolair), a medicine given by injection to patients with more severe asthma
Long-acting bronchodilators (such as Serevent) help open airways
Cromolyn sodium (Intal) or nedocromil sodium
Aminophylline or theophylline (not used as frequently as in the past)
Sometimes a combination of steroids and bronchodilators are used, using either separate inhalers or a single inhaler (such as Advair Diskus).
Quick relief, or rescue, medications are used to relieve symptoms during an attack. These include:
Short-acting bronchodilators (inhalers), such as Proventil, Ventolin, Xopenex, and others.
Corticosteroids, such as prednisone or methylprednisolone) given by mouth or into a vein
Persons with mild asthma (infrequent attacks) may use quick relief medication as needed. Those with persistent asthma should take control medications on a regular basis to prevent symptoms. A severe asthma attack requires a medical evaluation and may require a hospital stay, oxygen, and intravenous medications.
A peak flow meter, a simple device to measure lung volume, can be used at home to help you "see an attack coming" and take the appropriate action, sometimes even before any symptoms appear. If you are not monitoring asthma on a regular basis, an attack can take you by surprise.
Peak flow measurements can help show when medication is needed, or other action needs to be taken. Peak flow values of 50-80% of an individual’s personal best results indicate a moderate asthma attack, while values below 50% indicate a severe attack.There is no cure for asthma, though symptoms sometimes decrease over time. With proper self management and medical treatment, most people with asthma can lead normal lives.
Possible Complications
Respiratory fatigue
Side effects of asthma medications
Pneumothorax
Death
When to Contact a Medical Professional
Call for an appointment with your health care provider if you or your child experience mild asthma symptoms (to discuss treatment options).
Call your health care provider (or go to the emergency room) for moderate shortness of breath (shortness of breath with talking, peak flow 50-80% of personal best), if symptoms worsen or do not improve with treatment, or an attack requires more medication than recommended in the prescription.
Go to the emergency room for severe shortness of breath (shortness of breath at rest, peak flow less than 50% of personal best), if drowsiness or confusion develops, or for severe chest pain.
Prevention
Asthma symptoms can be substantially reduced by avoiding known allergens and respiratory irritants. If someone with asthma is sensitive to dust mites, exposure can be reduced by encasing mattresses and pillows in allergen-impermeable covers, removing carpets from bedrooms, and by vacuuming regularly. Exposure to dust mites and mold can be reduced by lowering indoor humidity.
If a person is allergic to an animal that cannot be removed from the home, the animal should be kept out of the patient's bedroom. Filtering material can be placed over the heating outlets to trap animal dander. Exposure to cigarette smoke, air pollution, industrial dusts, and irritating fumes should also be avoided.
Allergy desensitization may be helpful in reducing asthma symptoms and medication use, but the size of the benefit compared with other treatments is not known.
Guidelines for the Diagnosis and Management of Asthma -- Update on Selected Topics 2002. Bethesda, MD. 2003 June. National Asthma
Sunday, October 26, 2008
benefits of garlic in cancer
Written by Gloria Tsang, RDlast updated: October 2004
Health benefits of garlic are often reported. The most commonly known benefits of garlic are its potential role in heart disease and cancer. Read Benefits of Garlic in Heart Disease.
Benefits of Garlic: Cancer Prevention
Indeed, the first scientific report to study garlic and cancer was performed in the 1950s. Scientists injected allicin, an active ingredient from garlic, into mice suffering from cancer. Mice receiving the injection survived more than 6 months whereas those which did not receive the injection only survived 2 months.
Many studies showed that the organic ingredient of garlic, allyl sulfur, another active ingredient in garlic, are effective in inhibiting or preventing cancer development. Many observational studies in human being also investigated the association of using garlic and allyl sulfur and cancer. Out of the 37 studies, 28 studies showed evidence that garlic can prevent cancer. The evidence is particularly strong in prevention of prostate and stomach cancers. This particular study looking at the risk of stomach cancer was especially interesting. This study was conducted in China. Researchers found that smokers with high garlic intake have a relatively lower stomach cancer risk than smokers with low garlic intake.
A large-scale epidemiological Iowa Women's Health Study looked at the garlic consumption in 41,000 middle-aged women. Results showed that women who regularly consumed garlic had 35% lower risk of developing colon cancer.
It is thought that the allyl sulfur compounds in garlic prevent cancer by slowing or preventing the growth of the cancer tumor cells.
Garlic Key Message: In order to maximize the health benefits of garlic, it is suggested to wait 15 minutes between peeling and cooking garlic to allow the enzymatic reaction to occur to retain some health benefits of garlic. If you use garlic supplements, use the enteric coated tablets so that the healthy ingredients can survive the stomach and be absorbed into the bloodstream in the small intestines Please be cautious if you are taking garlic supplements and blood thinners such as aspirin and warfarin at the same time. Garlic supplements will further thin your blood. In addition, it is suggested to discontinue garlic supplementation at least 7 days prior to surgery.
Health benefits of garlic are often reported. The most commonly known benefits of garlic are its potential role in heart disease and cancer. Read Benefits of Garlic in Heart Disease.
Benefits of Garlic: Cancer Prevention
Indeed, the first scientific report to study garlic and cancer was performed in the 1950s. Scientists injected allicin, an active ingredient from garlic, into mice suffering from cancer. Mice receiving the injection survived more than 6 months whereas those which did not receive the injection only survived 2 months.
Many studies showed that the organic ingredient of garlic, allyl sulfur, another active ingredient in garlic, are effective in inhibiting or preventing cancer development. Many observational studies in human being also investigated the association of using garlic and allyl sulfur and cancer. Out of the 37 studies, 28 studies showed evidence that garlic can prevent cancer. The evidence is particularly strong in prevention of prostate and stomach cancers. This particular study looking at the risk of stomach cancer was especially interesting. This study was conducted in China. Researchers found that smokers with high garlic intake have a relatively lower stomach cancer risk than smokers with low garlic intake.
A large-scale epidemiological Iowa Women's Health Study looked at the garlic consumption in 41,000 middle-aged women. Results showed that women who regularly consumed garlic had 35% lower risk of developing colon cancer.
It is thought that the allyl sulfur compounds in garlic prevent cancer by slowing or preventing the growth of the cancer tumor cells.
Garlic Key Message: In order to maximize the health benefits of garlic, it is suggested to wait 15 minutes between peeling and cooking garlic to allow the enzymatic reaction to occur to retain some health benefits of garlic. If you use garlic supplements, use the enteric coated tablets so that the healthy ingredients can survive the stomach and be absorbed into the bloodstream in the small intestines Please be cautious if you are taking garlic supplements and blood thinners such as aspirin and warfarin at the same time. Garlic supplements will further thin your blood. In addition, it is suggested to discontinue garlic supplementation at least 7 days prior to surgery.
acid reflux diet
Written by Gloria Tsang, RDPublished in Nov 2004; updated in Sept 2006
Many people take over-the-counter antacids for a quick ease of acid reflux, but for most people, a proper diet is the best solution for overcoming acid reflux.
Acid Reflux Diet Myth
Myth 1: Drink milkA lot of people try drinking milk to ease acid reflux before sleep. But often, milk ends up causing acid reflux during sleep. To understand the whole situation, we have to realize that the problem roots from eating too much at dinner time. Eating a big meal at dinner causes excess stomach acid production. Drinking milk could be a quick fix to the acid reflux problem. Unfortunately, milk has a rebound action and would eventually encourage secretion of more stomach acid, which causes the acid reflux. To solve the problem, try adjusting your diet by eating a small meal at dinner and have a small snack such as crackers before sleep.
Myth 2: Avoid coffee, citrus fruits and Spicy foodWe have been told for years that coffee, acidic fruit as well as spicy foods can aggravate acid reflux. Therefore, we should avoid these in our daily diet in order to reduce acid reflux. A recent study published in the Archives of Internal Medicine in May 2006 showed that none of these myths hold true. Researchers from the Stanford University found that the only two behavioral changes can reduce symptoms of acid reflux - eating less and elevate your head while sleeping.
Acid Reflux Diet
First of all, try to eat small, frequent meals instead of three big meals a day. Small amounts of food each time would exert less workload on the stomach and therefore requires less acid secretion for digestion. Make sure to include foods that are high in complex carbohydrates in each meal. These foods, such as rice, breads and pasta, are able to tie up excess stomach acid and are often easy on the stomach.
Avoid high-fat meals such as those from the fast food chains. High fat foods will remain in the stomach longer, thus causing the need for more stomach acid in order to digest them.
But remember, don't overeat! Eating too much of any foods will stimulate the stomach to secret more acids for digestion.
Avoid or limit alcohol.
Maintain upright position during and at least 45 minutes after eating.
Try elevating the head of bed six to eight inches when lying down.
Don't think that beverages just quickly flow through your stomach without affecting acid production. Surprisingly, a lot of beverages stimulate acid secretion such as beer, wine and pop. The worst of all is beer. It could double your stomach acid within an hour.
Many people take over-the-counter antacids for a quick ease of acid reflux, but for most people, a proper diet is the best solution for overcoming acid reflux.
Acid Reflux Diet Myth
Myth 1: Drink milkA lot of people try drinking milk to ease acid reflux before sleep. But often, milk ends up causing acid reflux during sleep. To understand the whole situation, we have to realize that the problem roots from eating too much at dinner time. Eating a big meal at dinner causes excess stomach acid production. Drinking milk could be a quick fix to the acid reflux problem. Unfortunately, milk has a rebound action and would eventually encourage secretion of more stomach acid, which causes the acid reflux. To solve the problem, try adjusting your diet by eating a small meal at dinner and have a small snack such as crackers before sleep.
Myth 2: Avoid coffee, citrus fruits and Spicy foodWe have been told for years that coffee, acidic fruit as well as spicy foods can aggravate acid reflux. Therefore, we should avoid these in our daily diet in order to reduce acid reflux. A recent study published in the Archives of Internal Medicine in May 2006 showed that none of these myths hold true. Researchers from the Stanford University found that the only two behavioral changes can reduce symptoms of acid reflux - eating less and elevate your head while sleeping.
Acid Reflux Diet
First of all, try to eat small, frequent meals instead of three big meals a day. Small amounts of food each time would exert less workload on the stomach and therefore requires less acid secretion for digestion. Make sure to include foods that are high in complex carbohydrates in each meal. These foods, such as rice, breads and pasta, are able to tie up excess stomach acid and are often easy on the stomach.
Avoid high-fat meals such as those from the fast food chains. High fat foods will remain in the stomach longer, thus causing the need for more stomach acid in order to digest them.
But remember, don't overeat! Eating too much of any foods will stimulate the stomach to secret more acids for digestion.
Avoid or limit alcohol.
Maintain upright position during and at least 45 minutes after eating.
Try elevating the head of bed six to eight inches when lying down.
Don't think that beverages just quickly flow through your stomach without affecting acid production. Surprisingly, a lot of beverages stimulate acid secretion such as beer, wine and pop. The worst of all is beer. It could double your stomach acid within an hour.
antioxidants 101
Written by Gloria Tsang, RDPublished in Dec 2005; Updated in Aug 2007
What are Antioxidants? Benefits of Antioxidants
Antioxidants are substances or nutrients in our foods which can prevent or slow the oxidative damage to our body. When our body cells use oxygen, they naturally produce free radicals (by-products) which can cause damage. Antioxidants act as "free radical scavengers" and hence prevent and repair damage done by these free radicals. Health problems such as heart disease, macular degeneration, diabetes, cancer etc are all contributed by oxidative damage. Indeed, a recent study conducted by researchers from London found that 5 servings of fruits and vegetables reduce the risk of stroke by 25 percent. Antioxidants may also enhance immune defense and therefore lower the risk of cancer and infection.
Most Commonly Known Antioxidants
Vitamin A and Carotenoids
Carrots, squash, broccoli, sweet potatoes, tomatoes, kale, collards, cantaloupe, peaches and apricots (bright-colored fruits and vegetables!)
Vitamin C
Citrus fruits like oranges and lime etc, green peppers, broccoli, green leafy vegetables, strawberries and tomatoes
Vitamin E
Nuts & seeds, whole grains, green leafy vegetables, vegetable oil and liver oil
Selenium
Fish & shellfish, red meat, grains, eggs, chicken and garlic
Other Common Antioxidants
Some common phytochemicals
Flavonoids / polyphenols
soy
red wine
purple grapes or Concord grapes
pomegranate
cranberries
tea
Lycopene
Tomato and tomato products
pink grapefruit
watermelon
Lutein
dark green vegetables such as kale, broccoli, kiwi, brussels sprout and spinach
Lignan
flax seed
oatmeal
barley
rye
Vitamin-like Antioxidants:
Coenzyme Q10 (CoQ10)
Glutathione
Antioxidant enzymes made by the body:
superoxide dismutase (SOD)
catalase
glutathione peroxidase
Message: Antioxidants are found abundant in beans, grain products, fruits and vegetables. Look for fruits with bright color - lutein in some of the yellow pigments found in corn; orange in cantaloupe, butternut squash and mango; red from lycopene in tomatoes and watermelon, and purple and blue in berries. So enjoy eating a variety of these products. It is best to obtain these antioxidants from foods instead of supplements. In addition, minimize the exposure of oxidative stress such as smoking and sunburn.
Friday, October 17, 2008
guava
guava
Family: Myrtaceae Genus: Psidium Species: guajava Common names: Guava, goiaba, guayaba, djamboe, djambu, goavier, gouyave, goyave, goyavier, perala, bayawas, dipajaya jambu, petokal, tokal, guave, guavenbaum, guayave, banjiro, goiabeiro, guayabo, guyaba, goeajaaba, guave, goejaba, kuawa, abas, jambu batu, bayabas, pichi, posh, enandi Part Used: Fruit, leaf, bark From The Healing Power of Rainforest Herbs:
GUAVA
HERBAL PROPERTIES AND ACTIONS
Main Actions
Other Actions
Standard Dosage
stops diarrhea
depresses CNS
Leaves
kills bacteria
lowers blood pressure
Decoction: 1 cup 1-3
cups daily
kill fungi
reduces blood sugar
kills yeast
constricts blood vessels
kills amebas
promotes menstruation
relieves pain
fights free radicals
reduces spasms
supports heart
Called guayaba in Spanish-speaking countries and goiaba in Brazil, guava is a common shade tree or shrub in door-yard gardens in the tropics. It provides shade while the guava fruits are eaten fresh and made into drinks, ice cream, and preserves. In the richness of the Amazon, guava fruits often grow well beyond the size of tennis balls on well-branched trees or shrubs reaching up to 20 m high. Cultivated varieties average about 10 meters in height and produce lemon-sized fruits. The tree is easily identified by its distinctive thin, smooth, copper-colored bark that flakes off, showing a greenish layer beneath.
Guava fruit today is considered minor in terms of commercial world trade but is widely grown in the tropics, enriching the diet of hundreds of millions of people in the tropics of the world. Guava has spread widely throughout the tropics because it thrives in a variety of soils, propagates easily, and bears fruit relatively quickly. The fruits contain numerous seeds that can produce a mature fruit-bearing plant within four years. In the Amazon rainforest guava fruits are much enjoyed by birds and monkeys, which disperse guava seeds in their droppings and cause spontaneous clumps of guava trees to grow throughout the rainforest.
TRIBAL AND HERBAL MEDICINE USES
Guava may have been domesticated in Peru several thousand years ago; Peruvian archaeological sites have revealed guava seeds found stored with beans, corn, squash, and other cultivated plants. Guava fruit is still enjoyed as a sweet treat by indigenous peoples throughout the rainforest, and the leaves and bark of the guava tree have a long history of medicinal uses that are still employed today.
The Tikuna Indians decoct the leaves or bark of guava as a cure for diarrhea. In fact, an infusion or decoction made from the leaves and/or bark has been used by many tribes for diarrhea and dysentery throughout the Amazon, and Indians also employ it for sore throats, vomiting, stomach upsets, for vertigo, and to regulate menstrual periods. Tender leaves are chewed for bleeding gums and bad breath, and it is said to prevent hangovers (if chewed before drinking). Indians throughout the Amazon gargle a leaf decoction for mouth sores, bleeding gums, or use it as a douche for vaginal discharge and to tighten and tone vaginal walls after childbirth. A decoction of the bark and/or leaves or a flower infusion is used topically for wounds, ulcers and skin sores. Flowers are also mashed and applied to painful eye conditions such as sun strain, conjunctivitis or eye injuries.
Centuries ago, European adventurers, traders, and missionaries in the Amazon Basin took the much enjoyed and tasty fruits to Africa, Asia, India, and the Pacific tropical regions, so that it is now cultivated throughout the tropical regions of the world. Commercially the fruit is consumed fresh or used in the making of jams, jellies, paste or hardened jam, and juice. Guava leaves are in the Dutch Pharmacopoeia for the treatment of diarrhea, and the leaves are still used for diarrhea in Latin America, Central and West Africa, and Southeast Asia. In Peruvian herbal medicine systems today the plant is employed for diarrhea, gastroenteritis, intestinal worms, gastric disorders, vomiting, coughs, vaginal discharges, menstrual pain and hemorrhages, and edema. In Brazil guava is considered an astringent drying agent and diuretic and is used for the same conditions as in Peru. A decoction is also recommended as a gargle for sore throats, laryngitis and swelling of the mouth, and used externally for skin ulcers, and vaginal irritation and discharges.
PLANT CHEMICALS
Guava is rich in tannins, phenols, triterpenes, flavonoids, essential oils, saponins, carotenoids, lectins, vitamins, fiber and fatty acids. Guava fruit is higher in vitamin C than citrus (80 mg of vitamin C in 100 g of fruit) and contains appreciable amounts of vitamin A as well. Guava fruits are also a good source of pectin - a dietary fiber. The leaves of guava are rich in flavonoids, in particular, quercetin. Much of guava's therapeutic activity is attributed to these flavonoids. The flavonoids have demonstrated antibacterial activity. Quercetin is thought to contribute to the anti-diarrhea effect of guava; it is able to relax intestinal smooth muscle and inhibit bowel contractions. In addition, other flavonoids and triterpenes in guava leaves show antispasmodic activity. Guava also has antioxidant properties which is attributed to the polyphenols found in the leaves.
Guava's main plant chemicals include: alanine, alpha-humulene, alpha-hydroxyursolic acid, alpha-linolenic acid, alpha-selinene, amritoside, araban, arabinose, arabopyranosides, arjunolic acid, aromadendrene, ascorbic acid, ascorbigen, asiatic acid, aspartic acid, avicularin, benzaldehyde, butanal, carotenoids, caryophyllene, catechol-tannins, crataegolic acid, D-galactose, D-galacturonic acid, ellagic acid, ethyl octanoate, essential oils, flavonoids, gallic acid, glutamic acid, goreishic acid, guafine, guavacoumaric acid, guaijavarin, guajiverine, guajivolic acid, guajavolide, guavenoic acid, guajavanoic acid, histidine, hyperin, ilelatifol D, isoneriucoumaric acid, isoquercetin, jacoumaric acid, lectins, leucocyanidins, limonene, linoleic acid, linolenic acid, lysine, mecocyanin, myricetin, myristic acid, nerolidiol, obtusinin, octanol, oleanolic acid, oleic acid, oxalic acid, palmitic acid, palmitoleic acid, pectin, polyphenols, psidiolic acid, quercetin, quercitrin, serine, sesquiguavene, tannins, terpenes, and ursolic acid.
BIOLOGICAL ACTIVITIES AND CLINICAL RESEARCH
The long history of guava's use has led modern-day researchers to study guava extracts. Its traditional use for diarrhea, gastroenteritis and other digestive complaints has been validated in numerous clinical studies. A plant drug has even been developed from guava leaves (standardized to its quercetin content) for the treatment of acute diarrhea. Human clinical trials with the drug indicate its effectiveness in treating diarrhea in adults. Guava leaf extracts and fruit juice has also been clinically studied for infantile diarrhea. In a clinical study with 62 infants with infantile rotaviral enteritis, the recovery rate was 3 days (87.1%) in those treated with guava, and diarrhea ceased in a shorter time period than controls. It was concluded in the study that guava has "good curative effect on infantile rotaviral enteritis."
Guava has many different properties that contribute to its antidiarrheal effect: it has been documented with pronounced antibacterial, antiamebic and antispasmodic activity. It has also shown to have a tranquilizing effect on intestinal smooth muscle, inhibit chemical processes found in diarrhea and aid in the re-absorption of water in the intestines. In other research, an alcoholic leaf extract was reported to have a morphine-like effect, by inhibiting the gastrointestinal release of chemicals in acute diarrheal disease. This morphine-like effect was thought to be related to the chemical quercetin. In addition, lectin chemicals in guava were shown to bind to E-coli (a common diarrhea-causing organism), preventing its adhesion to the intestinal wall and thus preventing infection (and resulting diarrhea).
The effective use of guava in diarrhea, dysentery and gastroenteritis can also be related to guava's documented antibacterial properties. Bark and leaf extracts have shown to have in vitro toxic action against numerous bacteria. In several studies guava showed significant antibacterial activity against such common diarrhea-causing bacteria as Staphylococcus, Shigella, Salmonella, Bacillus, E. coli, Clostridium, and Pseudomonas. It has also demonstrated antifungal, anti-yeast (candida), anti-amebic, and antimalarial actions.
In a recent study with guinea pigs (in 2003) Brazilian researchers reported that guava leaf extracts have numerous effects on the cardiovascular system which might be beneficial in treating irregular heat beat (arrhythmia). Previous research indicated guava leaf provided antioxidant effects beneficial to the heart, heart protective properties, and improved myocardial function. In two randomized human studies, the consumption of guava fruit for 12 weeks was shown to reduce blood pressure by an average 8 points, decrease total cholesterol levels by 9%, decrease triglycerides by almost 8%, and increase "good" HDL cholesterol by 8%. The effects were attributed to the high potassium and soluble fiber content of the fruit (however 1-2 pounds of fruit was consumed daily by the study subjects to obtain these results!). In other animal studies guava leaf extracts have evidenced analgesic, sedative, and central nervous system (CNS) depressant activity, as well as a cough suppressant actions. The fruit or fruit juice has been documented to lower blood sugar levels in normal and diabetic animals and humans. Most of these studies confirm the plant's many uses in tropical herbal medicine systems.
CURRENT PRACTICAL USES
Guava, known as the poor man's apple of the tropics, has a long history of traditional use, much of which is being validated by scientific research. It is a wonderful natural remedy for diarrhea - safe enough even for young children. For infants and children under the age of 2, just a cup daily of guava fruit juice is helpful for diarrhea. For older children and adults, a cup once or twice daily of a leaf decoction is the tropical herbal medicine standard. Though not widely available in the U.S. market, tea-cut and powdered leaves can be obtained from larger health food stores or suppliers of bulk botanicals. Newer in the market are guava leaf extracts that are used in various herbal formulas for a myriad of purposes; from herbal antibiotic and diarrhea formulas to bowel health and weight loss formulas. Toxicity studies with rats and mice, as well as controlled human studies show both the leaf and fruit to be safe and without side effects.
GUAVA PLANT SUMMARY
Main Preparation Method: decoction
Main Actions (in order): antidysenteric, antiseptic, antibacterial, antispasmodic, cardiotonic (tones, balances, strengthens the heart)
Main Uses:
for dysentery (bacterial and amebic), diarrhea, colic, and infantile rotavirus enteritis
as a broad-spectrum antimicrobial for internal and external bacterial, fungal, candidal, and amebic infections
to tone, balance, protect and strengthen the heart (and for arrhythmia and some heart diseases)
as a cough suppressant, analgesic (pain-reliever), and febrifuge (reduces fever) for colds, flu, sore throat, etc
as a topical remedy for ear and eye infections Properties/Actions Documented by Research: amebicide, analgesic (pain-reliever), antibacterial, anticandidal, antidysenteric, antifungal, antimalarial, antioxidant, antispasmodic, antiulcerous, cardiodepressant, cardiotonic (tones, balances, strengthens the heart), central nervous system depressant, cough suppressant, gastrototonic (tones, balances, strengthens the gastric tract), hypotensive (lowers blood pressure), sedative, vasoconstrictor
Other Properties/Actions Documented by Traditional Use:anti-anxiety, anticonvulsant, antiseptic, astringent, blood cleanser, digestive stimulant, menstrual stimulant, nervine (balances/calms nerves), vermifuge (expels worms)
Cautions: It has a cardiac depressant effect and is contraindicated in some heart conditions.
Traditional Preparation: The fruit and juice is freely consumed for its great taste, nutritional benefit and nutrient content, as well as an effective children's diarrhea remedy. The leaves are prepared in a standard decoction and dosages are generally 1 cup 1-3 times daily.
Contraindications:
Guava has recently demonstrated cardiac depressant activity and should be used with caution by those on heart medications.
Guava fruit has shown to lower blood sugar levels and it should be avoided by people with hypoglycemia.
Drug Interactions: None reported, however excessive or chronic consumption of guava may potentiate some heart medications.
WORLDWIDE ETHNOMEDICAL USES
Amazonia
for diarrhea, dysentery, menstrual disorders, stomachache, vertigo
Brazil
for anorexia, cholera, diarrhea, digestive problems, dysentery, gastric insufficiency, inflamed mucous membranes, laryngitis, mouth(swelling), skin problems, sore throat, ulcers, vaginal discharge
Cuba
for colds, dysentery, dyspepsia
Ghana
coughs, diarrhea, dysentery, toothache
Haiti
for dysentery, diarrhea, epilepsy, itch, piles, scabies, skin sores, sore throat, stomachache, wounds, and as an antiseptic and astringent
India
for anorexia, cerebral ailments, childbirth, chorea, convulsions, epilepsy, nephritis
Malaya
for dermatosis, diarrhea, epilepsy, hysteria, menstrual disorders
Mexico
for deafness, diarrhea, itch, scabies, stomachache, swelling, ulcer, worms, wounds
Peru
for conjunctivitis, cough, diarrhea, digestive problems, dysentery, edema, gout, hemorrhages, gastroenteritis, gastritis, lung problems, PMS, shock, vaginal discharge, vertigo, vomiting, worms
Philippines
for sores, wounds, and as an astringent
Trinidad
bacterial infections, blood cleansing, diarrhea, dysentery
Elsewhere
for anorexia, aches, bacterial infections, boils, bowel disorders, bronchitis, catarrh, cholera, chorea, colds, colic, convulsions, coughs, diarrhea, dysentery, dyspepsia, edema, epilepsy, fever, gingivitis, hemorrhoids, itch, jaundice, menstrual problems, nausea, nephritis, respiratory problems, rheumatism, scabies, sore throat, spasms, sprains, stomach problems, swelling, tonic, toothache, ulcers, worms, wounds, and as an antiseptic and astringent
References/Footnotes:
Conde Garcia, E. A., et al. “Inotropic effects of extracts of Psidium guajava L. (guava) leaves on the guinea pig atrium.” Braz. J. of Med. & Biol. Res. 2003; 36: 661-668.
Suntornsuk, L., et al. “Quantitation of vitamin C content in herbal juice using direct titration.” J. Pharm. Biomed. Anal. 2002; 28(5): 849-55.
Beckstrom-Sternberg, S. M., et al. “The phytochemical database.” (ACEDB version 4.3-Data version July 1994.) National Germplasm Resources Laboratory (NGRL), Agricultural Research Service (ARS), U.S. Department of Agriculture.
Jimenez-Escrig, A., et al. “Guava fruit (Psidium guajava L.) as a new source of antioxidant dietary fiber.” J. Agric. Food Chem. 2001; 49(11): 5489-93.
Smith, Nigel J. H., et al. Tropical Forests and their Crops. London: Cornell University Press. 1992.
Arima, H., et al. “Isolation of antimicrobial compounds from guava (Psidium guajava L.) and their structural elucidation.” Biosci. Biotechnol. Biochem. 2002; 66(8): 1727-30.
Morales, M. A., et al. “Calcium-antagonist effect of quercetin and its relation with the spasmolytic properties of Psidium guajava L.” Arch. Med. Res. 1994; 25(1): 17-21.
Lozoya, X., et al. “Quercetin glycosides in Psidium guajava L. leaves and determination of a spasmolytic principle.” Arch. Med. Res. 1994; 25(1): 11-5.
Begum, S., et al. “Triterpenoids from the leaves of Psidium guajava.” Phytochemistry 2002; 61(4): 399-403.
Lozoya, X., et al. “Intestinal anti-spasmodic effect of a phytodrug of Psidium guajava folia in the treatment of acute diarrheic disease.” J. Ethnopharmacol. 2002; 83(1-2): 19-24.
Wei, L., et al. “Clinical study on treatment of infantile rotaviral enteritis with Psidium guajava L.” Zhongguo Zhong Xi Yi Jie He Za Zhi 2000; 20(12): 893-5.
Tona, L., et al. “Biological screening of traditional preparations from some medicinal plants used as antidiarrhoeal in Kinshasa, Congo.” Phytomedicine 1999; 6(1): 59-66.
Lozoya, X., et al. “Model of intraluminal perfusion of the guinea pig ileum in vitro in the study of the antidiarrheal properties of the guava (Psidium guajava).” Arch. Invest. Med. (Mex). 1990; 21(2): 155-62.
Almeida, C. E., et al. “Analysis of antidiarrhoeic effect of plants used in popular medicine.” Rev. Saude Publica. 1995; 29(6): 428-33.
Lin, J., et al. “Anti-diarrhoeal evaluation of some medicinal plants used by Zulu traditional healers.” J. Ethnopharmacol. 2002; 79(1): 53-6.
Lutterodt, G. D. “Inhibition of Microlax-induced experimental diarrhea with narcotic-like extracts of Psidium guajava leaf in rats.” J. Ethnopharmacol. 1992; 37(2): 151-7.
Lutterodt, G. D. “Inhibition of gastrointestinal release of acetylcholine by quercetin as a possible mode of action of Psidium guajava leaf extracts in the treatment of acute diarrhoeal disease.” J. Ethnopharmcol. 1989; 25(3): 235-47.
Coutino-Rodriguez, R., et al, “Lectins in fruits having gastrointestinal activity: their participation in the hemagglutinating property of Escherichia coli O157:H7.” Arch. Med. Res. 2001; 32(4): 251-7.
Abdelrahim, S. I., et al. “Antimicrobial activity of Psidium guajava L.” Fitoterapia 2002; 73(7-8): 713-5.
Holetz, F. B., et al. “Screening of some plants used in the Brazilian folk medicine for the treatment of infectious diseases.” Mem. Inst. Oswaldo Cruz 2002; 97(7): 1027-31.
Caceres, A., et al. “Plants used in Guatemala for the treatment of gastrointestinal disorders. 1. Screening of 84 plants against enterobacteria.” J. Ethnopharmacol. 1990; 30(1): 55-73.
Garcia, S., et al, “Inhibition of growth, enterotoxin production, and spore formation of Clostridium perfringens by extracts of medicinal plants.” J. Food Prot. 2002; 65(10): 1667-9.
Tona, L., et al. “Antiamoebic and spasmolytic activities of extracts from some antidiarrhoeal traditional preparations used in Kinshasa, Congo.” Phytomedicine 2000; 7(1): 31-8.
Tona, L., et al. “Antiamoebic and phytochemical screening of some Congolese medicinal plants.” J. Ethnopharmacol. 1998; 61(1): 57-65.
Nundkumar, N., et al. “Studies on the antiplasmodial properties of some South African medicinal plants used as antimalarial remedies in Zulu folk medicine.” Methods Find Exp. Clin. Pharmacol. 2002; 24(7): 397-401.
Yamashiro, S., et al. “Cardioprotective effects of extracts from Psidium guajava L. and Limonium wrigth II, Okinawan medicinal plants, against ischemia-reperfusion injury in perfused rat hearts.” Pharmacology 2003; 67(3): 128-35.
Singh, R. B., et al. “Can guava fruit intake decrease blood pressure and blood lipids?” J. Hum Hypertens. 1993; 7(1): 33-8.
Singh, R. B., et al. “Effects of guava intake on serum total and high-density lipoprotein cholesterol levels and on systemic blood pressure.” Am. J. Cardiol. 1992; 70(15): 1287-91.
Shaheen, H. M., et al. “Effect of Psidium guajava leaves on some aspects of the central nervous system in mice.” Phytother. Res. 2000; 14(2): 107-11.
Lutterodt, G. D., et al. “Effects on mice locomotor activity of a narcotic-like principle from Psidium guajava leaves.” J. Ethnopharmacol. 1988; 24(2-3): 219-31.
Jaiarj, P., et al. “Anticough and antimicrobial activities of Psidium guajava Linn. leaf extract.” J. Ethnopharmacol. 1999; 67(2): 203-12.
Cheng, J. T., et al. “Hypoglycemic effect of guava juice in mice and human subjects.” Am. J. Clin. Med. 1983; 11(1-4): 74-6.
Roman-Ramos, R., et al. "Anti-hyperglycemic effect of some edible plants." J. Ethnopharmacol. 1995.
The above text has been printed from The Healing Power of Rainforest Herbs by Leslie Taylor, copyrighted © 2005 All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, including websites, without written permission.
† The statements contained herein have not been evaluated by the Food and Drug Administration. The information contained in this plant database file is intended for education, entertainment and information purposes only. This information is not intended to be used to diagnose, prescribe or replace proper medical care. The plant described herein is not intended to treat, cure, diagnose, mitigate or prevent any disease. Please refer to our Conditions of Use for using this plant database file and web site.
Thursday, October 16, 2008
causes of secondary high blood pressure
What are the causes of secondary high blood pressure
As mentioned previously, 5% of people with hypertension have what is called secondary hypertension. This means that the hypertension in these individuals is secondary to (caused by) a specific disorder of a particular organ or blood vessel, such as the kidney, adrenal gland, or aortic artery.
Renal (kidney) hypertension
Diseases of the kidneys can cause secondary hypertension. This type of secondary hypertension is called renal hypertension because it is caused by a problem in the kidneys. One important cause of renal hypertension is narrowing (stenosis) of the artery that supplies blood to the kidneys (renal artery). In younger individuals, usually women, the narrowing is caused by a thickening of the muscular wall of the arteries going to the kidney (fibromuscular hyperplasia). In older individuals, the narrowing generally is due to hard, fat-containing (atherosclerotic) plaques that are blocking the renal artery.
How does narrowing of the renal artery cause hypertension? First, the narrowed renal artery impairs the circulation of blood to the affected kidney. This deprivation of blood then stimulates the kidney to produce the hormones, renin and angiotensin. These hormones, along with aldosterone from the adrenal gland, cause a constriction and increased stiffness (resistance) in the peripheral arteries throughout the body, which results in high blood pressure.
Renal hypertension is usually first suspected when high blood pressure is found in a young individual or a new onset of high blood pressure is discovered in an older person. Screening for renal artery narrowing then may include renal isotope (radioactive) imaging, ultrasonographic (sound wave) imaging, or magnetic resonance imaging (MRI) of the renal arteries. The purpose of these tests is to determine whether there is a restricted blood flow to the kidney and whether angioplasty (removal of the restriction in the renal arteries) is likely to be beneficial. However, if the ultrasonic assessment indicates a high resistive index within the kidney (high resistance to blood flow), angioplasty may not improve the blood pressure because chronic damage in the kidney from long-standing hypertension already exists. If any of these tests are abnormal or the doctor's suspicion of renal artery narrowing is high enough, renal angiography (an x-ray study in which dye is injected into the renal artery) is done. Angiography is the ultimate test to actually visualize the narrowed renal artery.
A narrowing of the renal artery may be treated by balloon angioplasty. In this procedure, the physician threads a long narrow tube (catheter) into the renal artery. Once the catheter is there, the renal artery is widened by inflating a balloon at the end of the catheter and placing a permanent stent (a device that stretches the narrowing) in the artery at the site of the narrowing. This procedure usually results in an improved blood flow to the kidneys and lower blood pressure. Moreover, the procedure also preserves the function of the kidney that was partially deprived of its normal blood supply. Only rarely is surgery needed these days to open up the narrowing of the renal artery.
Any of the other types of chronic kidney disease that reduces the function of the kidneys can also cause hypertension due to hormonal disturbances and/or retention of salt.
It is important to remember that not only can kidney disease cause hypertension, but hypertension can also cause kidney disease. Therefore, all patients with high blood pressure should be evaluated for the presence of kidney disease so they can be treated appropriately.
Adrenal gland tumors
Two rare types of tumors of the adrenal glands are less common, secondary causes of hypertension. The adrenal glands sit right on top of the kidneys. Both of these tumors produce excessive amounts of adrenal hormones that cause high blood pressure. These tumors can be diagnosed from blood tests, urine tests, and imaging studies of the adrenal glands. Surgery is often required to remove these tumors or the adrenal gland (adrenalectomy), which usually relieves the hypertension.
One of the types of adrenal tumors causes a condition that is called primary hyperaldosteronism because the tumor produces excessive amounts of the hormone aldosterone. In addition to the hypertension, this condition causes the loss of excessive amounts of potassium from the body into the urine, which results in a low level of potassium in the blood. Hyperaldosteronism is generally first suspected in a person with hypertension when low potassium is also found in the blood. (Also, certain rare genetic disorders affecting the hormones of the adrenal gland can cause secondary hypertension.)
The other type of adrenal tumor that can cause secondary hypertension is called a pheochromocytoma. This tumor produces excessive catecholamines, which include several adrenaline-related hormones. The diagnosis of a pheochromocytoma is suspected in individuals who have sudden and recurrent episodes of hypertension that are associated with flushing of the skin, rapid heart beating (palpitations), and sweating, in addition to the symptoms associated with high blood pressure.
Coarctation of the aorta
Coarctation of the aorta is a rare hereditary disorder that is one of the most common causes of hypertension in children. This condition is characterized by a narrowing of a segment of the aorta, the main large artery coming from the heart. The aorta delivers blood to the arteries that supply all of the body's organs, including the kidneys.
The narrowed segment (coarctation) of the aorta generally occurs above the renal arteries, which causes a reduced blood flow to the kidneys. This lack of blood to the kidneys prompts the renin-angiotensin-aldosterone hormonal system to elevate the blood pressure. Treatment of the coarctation is usually the surgical correction of the narrowed segment of the aorta. Sometimes, balloon angioplasty (as described above for renal artery stenosis) can be used to widen (dilate) the coarctation of the aorta.
The metabolic syndrome and obesity
Genetic factors play a role in the constellation of findings that make up the "metabolic syndrome." Individuals with the metabolic syndrome have insulin resistance and a tendency to have type 2 diabetes mellitus (non-insulin-dependent diabetes).
Obesity, especially associated with a marked increase in abdominal girth, leads to high blood sugar (hyperglycemia), elevated blood lipids (fats), vascular inflammation, endothelial dysfunction (abnormal reactivity of the blood vessels), and hypertension all leading to premature atherosclerotic vascular disease. The American Obesity Association states the risk of developing hypertension is five to six times greater in obese Americans, age 20 to 45, compared to non-obese individuals of the same age. The American Journal of Clinical Nutrition reported in 2005 that waist size was a better predictor of a person's blood pressure than body mass index (BMI). Men should strive for a waist size of 35 inches or under and women 33 inches or under. The epidemic of obesity in the United States contributes to hypertension in children, adolescents, and adults.
As mentioned previously, 5% of people with hypertension have what is called secondary hypertension. This means that the hypertension in these individuals is secondary to (caused by) a specific disorder of a particular organ or blood vessel, such as the kidney, adrenal gland, or aortic artery.
Renal (kidney) hypertension
Diseases of the kidneys can cause secondary hypertension. This type of secondary hypertension is called renal hypertension because it is caused by a problem in the kidneys. One important cause of renal hypertension is narrowing (stenosis) of the artery that supplies blood to the kidneys (renal artery). In younger individuals, usually women, the narrowing is caused by a thickening of the muscular wall of the arteries going to the kidney (fibromuscular hyperplasia). In older individuals, the narrowing generally is due to hard, fat-containing (atherosclerotic) plaques that are blocking the renal artery.
How does narrowing of the renal artery cause hypertension? First, the narrowed renal artery impairs the circulation of blood to the affected kidney. This deprivation of blood then stimulates the kidney to produce the hormones, renin and angiotensin. These hormones, along with aldosterone from the adrenal gland, cause a constriction and increased stiffness (resistance) in the peripheral arteries throughout the body, which results in high blood pressure.
Renal hypertension is usually first suspected when high blood pressure is found in a young individual or a new onset of high blood pressure is discovered in an older person. Screening for renal artery narrowing then may include renal isotope (radioactive) imaging, ultrasonographic (sound wave) imaging, or magnetic resonance imaging (MRI) of the renal arteries. The purpose of these tests is to determine whether there is a restricted blood flow to the kidney and whether angioplasty (removal of the restriction in the renal arteries) is likely to be beneficial. However, if the ultrasonic assessment indicates a high resistive index within the kidney (high resistance to blood flow), angioplasty may not improve the blood pressure because chronic damage in the kidney from long-standing hypertension already exists. If any of these tests are abnormal or the doctor's suspicion of renal artery narrowing is high enough, renal angiography (an x-ray study in which dye is injected into the renal artery) is done. Angiography is the ultimate test to actually visualize the narrowed renal artery.
A narrowing of the renal artery may be treated by balloon angioplasty. In this procedure, the physician threads a long narrow tube (catheter) into the renal artery. Once the catheter is there, the renal artery is widened by inflating a balloon at the end of the catheter and placing a permanent stent (a device that stretches the narrowing) in the artery at the site of the narrowing. This procedure usually results in an improved blood flow to the kidneys and lower blood pressure. Moreover, the procedure also preserves the function of the kidney that was partially deprived of its normal blood supply. Only rarely is surgery needed these days to open up the narrowing of the renal artery.
Any of the other types of chronic kidney disease that reduces the function of the kidneys can also cause hypertension due to hormonal disturbances and/or retention of salt.
It is important to remember that not only can kidney disease cause hypertension, but hypertension can also cause kidney disease. Therefore, all patients with high blood pressure should be evaluated for the presence of kidney disease so they can be treated appropriately.
Adrenal gland tumors
Two rare types of tumors of the adrenal glands are less common, secondary causes of hypertension. The adrenal glands sit right on top of the kidneys. Both of these tumors produce excessive amounts of adrenal hormones that cause high blood pressure. These tumors can be diagnosed from blood tests, urine tests, and imaging studies of the adrenal glands. Surgery is often required to remove these tumors or the adrenal gland (adrenalectomy), which usually relieves the hypertension.
One of the types of adrenal tumors causes a condition that is called primary hyperaldosteronism because the tumor produces excessive amounts of the hormone aldosterone. In addition to the hypertension, this condition causes the loss of excessive amounts of potassium from the body into the urine, which results in a low level of potassium in the blood. Hyperaldosteronism is generally first suspected in a person with hypertension when low potassium is also found in the blood. (Also, certain rare genetic disorders affecting the hormones of the adrenal gland can cause secondary hypertension.)
The other type of adrenal tumor that can cause secondary hypertension is called a pheochromocytoma. This tumor produces excessive catecholamines, which include several adrenaline-related hormones. The diagnosis of a pheochromocytoma is suspected in individuals who have sudden and recurrent episodes of hypertension that are associated with flushing of the skin, rapid heart beating (palpitations), and sweating, in addition to the symptoms associated with high blood pressure.
Coarctation of the aorta
Coarctation of the aorta is a rare hereditary disorder that is one of the most common causes of hypertension in children. This condition is characterized by a narrowing of a segment of the aorta, the main large artery coming from the heart. The aorta delivers blood to the arteries that supply all of the body's organs, including the kidneys.
The narrowed segment (coarctation) of the aorta generally occurs above the renal arteries, which causes a reduced blood flow to the kidneys. This lack of blood to the kidneys prompts the renin-angiotensin-aldosterone hormonal system to elevate the blood pressure. Treatment of the coarctation is usually the surgical correction of the narrowed segment of the aorta. Sometimes, balloon angioplasty (as described above for renal artery stenosis) can be used to widen (dilate) the coarctation of the aorta.
The metabolic syndrome and obesity
Genetic factors play a role in the constellation of findings that make up the "metabolic syndrome." Individuals with the metabolic syndrome have insulin resistance and a tendency to have type 2 diabetes mellitus (non-insulin-dependent diabetes).
Obesity, especially associated with a marked increase in abdominal girth, leads to high blood sugar (hyperglycemia), elevated blood lipids (fats), vascular inflammation, endothelial dysfunction (abnormal reactivity of the blood vessels), and hypertension all leading to premature atherosclerotic vascular disease. The American Obesity Association states the risk of developing hypertension is five to six times greater in obese Americans, age 20 to 45, compared to non-obese individuals of the same age. The American Journal of Clinical Nutrition reported in 2005 that waist size was a better predictor of a person's blood pressure than body mass index (BMI). Men should strive for a waist size of 35 inches or under and women 33 inches or under. The epidemic of obesity in the United States contributes to hypertension in children, adolescents, and adults.
childhood paracetamol
Childhood Paracetamol Use Linked to Later Asthma Symptoms
FRIDAY, Sept. 19 (HealthDay News) -- The use of paracetamol (acetaminophen), whether in the first year of life or later in childhood, is associated with higher risk of asthma symptoms at ages 6 and 7, according to research published in the Sept. 20 issue of The Lancet.
Richard Beasley, of the Medical Research Institute of New Zealand in Wellington, and colleagues analyzed data from 205,487 children in 31 countries. Parents of these 6- and 7-year-olds answered questions about children's symptoms of asthma, eczema and rhinoconjunctivitis, along with history of paracetamol use.
The use of paracetamol for fever during children's first year of life was associated with an elevated risk of asthma symptoms (odds ratio, 1.46), the researchers report. High and medium recent use of paracetamol was also associated with increased risk of asthma symptoms compared to no use (ORs 3.23 and 1.61, respectively). Use of the drug, either recently or in the first year, was also associated with higher risk of symptoms of eczema and rhinoconjunctivitis, the investigators found.
"Paracetamol use at recommended therapeutic doses could result in depletion of glutathione and glutathione-dependent enzymes, thereby reducing the ability to withstand oxidative stress. The generation of reactive oxygen species after allergic, viral or other non-allergic stimuli may then result in enhanced inflammation, which could lead to the development or worsening of pre-existing asthma, rhinoconjunctivitis or eczema, dependent on the organ systems affected," the authors write.
Glaxo Wellcome New Zealand and Glaxo Wellcome International Medical Affairs provided funding for the study. Beasley disclosed a financial relationship with GlaxoSmithKline
basic pharmacology
Basic Pharmacology
Introduction
Pharmacology is the study of drugs. Drug are defined as chemical substances that have an effect on a living
organism; medicines are drugs used to prevent or treat disease. The administration route, health and age of the
patient, and the chemical structure of the drug all play a role in how fast it will act. A drug is considered effective
if it elicits the desired therapeutic response with minimal side effects.
ALL drugs elicit more than one response and the use of multiple drugs at the same time may lead to desirable
or dangerous drug interactions. Fortunately, due to effective drug control laws, the desired therapeutic response
usually occurs and the side effects of most official drugs are predictable, minimal and can be reduced by adjusting
the dose of the drug. That-being-said, a few patients experience side effects strong enough to warrant discontinuing
the drug treatment regime. Unlike most side effects, systemic allergic reactions are unpredictable and while most
result in hives some cause respiratory distress, vascular collapse, and death. Interactions between multiple drugs
taken concurrently may result in either an increase or decrease of one or both drugs due to changes in each drug’s
absorption, distribution, metabolism, or excretion (ADME) characteristics. The majority of drug interactions are
known and can be prevented by checking the appropriate data base. Patients taking any form of drug should be
monitored for side effects, systemic allergic reactions, and drug interactions (if taking more than one drug).
Drug Classifications
Drugs fall into two distinct categories: those that require a physician’s prescription to obtain (Rx) and those
that can be purchased over-the-counter (OTC).
Within these categories they are further classified by the body system they effect, how they are used, or how
they elicit their response. Drugs may be referred to by their chemical names, official names, brand names, or by
their generic names. Because it describes the drug’s exact molecular structure the chemical name is complex and
really only useful to chemists. Upon approval the Federal Drug Administration (FDA) gives each drug an official
name. Trademark or brand names are proprietary and assigned and registered by the drug’s manufacturer. In order
to distinguish them from generic names, official drug names and brand names are capitalized when in print. The
generic name is non-proprietary, simpler, and not capitalized when in print. In order to avoid confusion ALL drugs
in this book are referred to by their generic names.
How Drugs Work—An Conceptual Overview
Most drugs act by forming chemical bonds with specific receptor sites within the body to stimulate and/or
inhibit a response. While drugs alter the body’s physiologic activity along existing chemical pathways, they DO
NOT create new pathways or responses. The success of a drug’s response depends on two factors: it’s molecular
fit and the number of receptor sites it bonds to. The better the fit and the greater number of receptor sites occupied,
the stronger the response. In order for drugs elicit a response they must first be dissolved in the patient’s blood
or plasma and then transported to their respective receptor sites. Once dissolved, they go thorough four distinct
stages absorption, distribution, metabolism, and excretion (ADME).
Absorption is the process by which a drug is transported from its administration site into general circulation.
The rate of absorption depends on the patient’s hydration status, the administration route, the blood flow through
the tissue at the administration site, and the solubility of the drug.
Once absorbed most drugs bind to—and are carried by—plasma proteins in the blood and lymph for distribution.
When bound, the large size of the resulting drug/protein complex prevent the drug from crossing the vascular
membranes into the tissue; and a drug MUST cross into tissue to bathe receptor sites, become metabolized by
the liver, or be excreted by the kidneys. Furthermore, once in the extra cellular space, fat soluble drugs are likely
to bind to fat cells rendering them temporally inactive. As serum drug levels change due to a drug response, metabolism,
or excretion, molecules of the bound drug are released from the drug/protein complex and/or fat cells to
maintain the equilibrium between the free and bound drug. It is only the unbound drug in solution that is pharmacologically
active. The amount of the drug that reaches the receptor sites determines the strength of its response.
Recptor Site (Lock)
Drug (Key)
Agonist Antagonist Partial Agonist
An agonist bonds and fits well enough into the recptor
site to elicits a strong response. An antagonist bonds but
does NOT fit well enough to elicit a response. A partial agonist
bonds but only fits well enough into the site to elicit a
partial response. As long as a site is occupied other drugs
are prevented from bonding to the same site.
Lock & Key Principle of Drug Action
Serum levels of the drug MUST remain within a specific range in order to render the desired therapeutic effect.
Enzymes produced by the liver are the body’s primary way of breaking down drugs and preparing them for
removal (metabolism). Once inactivated, drug metabolites—and in some cases the active drug—are excreted
from the body primarily through the urinary system and kidneys. Other less utilized removal methods are via the
GI tract (bile), lungs (exhalation), and skin. Age, disease, smoking, and dehydration may decrease liver and renal
function slowing both drug metabolism and excretion.
Drug/Plasma Protein Complex
Drug Bound to Fat Celll
Free Drug
Drug Recptor Site
Drug in
Circulation
Drug in Tissue
Drug Administration in a Wilderness Environment
Drugs are administered by one of three routes: through the digestive system via ingestion, directly into
the body’s fluid reservoir via injection, and through body membranes via the lungs, mucus membranes, or skin.
Choosing and administering a drug in a wilderness context by non-physicians should be done only in specific
circumstances and according to protocols established by the expedition’s—or organization’s—physician advisor.
Hydration, even in healthy people, is always a concern in a wilderness environment and becomes even more so
when administering drugs. Because dehydration equals poor absorption, distribution, metabolism, and excretion
(ADME) and inhibits the desired therapeutic response, make sure that your patient is well-hydrated before administrating
any drugs.
Because oral drugs are effective, easy to carry, and simple to administer, they tend to make up the majority
of the drugs carried in an expedition first aid kit. Before an oral medication can reach general circulation it must
survive the acids and enzymes of the digestive system, be successfully transported across the stomach or intestinal
lining, and survive the initial pass through the liver. Throughout the process hydration is extremely important;
even in a well-hydrated patient oral medications should be given with water (8 oz minimum).
The skin and mucus membranes are another common drug administration route used in a wilderness setting
because, like oral drugs, they are effective, easy to carry, and simple to administer. Ear and eye drops are used to
treat local infections as are vaginal suppositories. Rectal suppositories are used to treat constipation. Topical skin
ointments are used to treat local allergic reactions, promote healing in partial thickness wounds, treat a variety
of sub-cutaneous fungal infections. Sub-lingual or buccal glucose tablets are used to treat hypoglycemia in the
insulin dependant diabetic and sub-lingual tablets are used to treat angina.
Absorption via inhalation is influenced by the depth of the patient’s respirations. Absorption in the lungs is
more effective when a spacer is used to disperse the medication prior to inhalation and the patient can take a deep
breath and hold the drug in their lungs for a few seconds before exhaling. In a wilderness setting the inhalation
route tends to be reserved for participants suffering from asthma.
While all types of injections bypass the digestive system and frequently offer the fastest absorption and
distribution route, they should NOT be the first choice for a expedition first aid kit because they are expensive,
difficult to carry, and require advanced training to use. Subcutaneous (SC) and intramuscular (IM) injections
of epinephrine are commonly given—primarily by auto-injectors—to treat systemic allergic reactions, Because
there are more blood vessels in muscles than in subcutaneous tissue, absorption is faster via IM injection. Give
IM injections in the muscle belly where blood flow is the greatest and there are no large arteries or veins; the most
common sight used in the field is the anterior thigh. While intravenous (IV) injections provide the most direct
route to the blood, IV solutions and kits are rarely carried due their relatively high weight, low need, storage problems,
difficulty of administration in challenging environments, and the high level of training needed to administer
them correctly even under the best of circumstances. Intraosseous (IO) or bone injections are similar to IVs in that
they require specialized equipment and training but are easier to use in hazardous environments. Both IV and IO
injections tend to be reserved for inbound rescue teams who respond with field paramedics, nurses, or physicians
and have the capacity to carry a lot of gear.
When choosing a drug, make sure that you:
• adhere to your protocols
• review the patient’s history for prior systemic allergic reactions to the drug
• there is no possibility of dangerous drug interactions if multiple drugs are to be given
• review and advise the patient of the possible side effects
Prior to administration, assess and document the patient’s response to any prior medications and make sure
they are hydrated. Make sure you have the:
• Right patient
• Right dru
• Right administration route
• Right dose
• Right time
After administering the drug, document all of the above in the patient’s SOAP note and/or a separate drug log.
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