September 15, 2008, 10:14 PM CT

Guideline for drug treatment of osteoporosis

The American College of Physicians (ACP) today released a new clinical practice guideline on drug therapy of osteoporosis or low bone density to prevent fracture in men and women. The guideline appears in the September 16, 2008, issue of Annals of Internal Medicine

ACP recommends that physicians offer drug therapy to men and women who have been diagnosed with osteoporosis or a prior fracture not caused by substantial trauma. The guideline also recommends that doctors and their patients consider drug therapy to prevent fracture for men and women who are at risk of developing osteoporosis.

The authors did not find evidence to prove that one drug is definitively better than another medication. They recommend that physicians make individual therapy decisions based on the risks, benefits, and side effects profile of available drug options. However, there is good information that bisphosphonates are reasonable options for beginning drug therapy as they decrease the risk of vertebral, non-vertebral, and hip fractures.

"Because therapy options may affect various parts of skeletal system differently, we analyzed the available evidence on numerous drugs to prevent fractures in men and women," said Vincenza Snow, MD, FACP, a co-author of the guideline and director of clinical programs and quality of care at ACP. "Bisphosphonates can be considered a first-line treatment, especially for patients at risk for hip fracture. However, there is no clear evidence showing the appropriate duration of therapy with these drugs"......... Posted by: Emily      Read more         Source

September 15, 2008, 9:29 PM CT

Estradiol may stimulate collagen production in aging skin

Applying the hormone estradiol to skin protected from the sun appears to stimulate production of the protein collagen in older men and women, as per a report in the recent issue of Archives of Dermatology, one of the JAMA/Archives journals. However, it may not have the same effect on sun-exposed skin, such as the face or arms.

As skin ages, its function is reduced, it becomes more fragile and wound healing is compromised, as per background information in the article. On areas of the body that are typically not covered by clothing, long-term exposure to the sun's ultraviolet rays causes skin to look prematurely old, a process known as photo-aging. Natural aging and photo-aging share biochemical features, including a reduction in collagen, the major protein that forms the structure of skin's inner layer.

Laure Ritti, Ph.D., and his colleagues at the University of Michigan Medical School, Ann Arbor, recruited 70 healthy volunteers (40 postmenopausal women and 30 men, average age 75 years) with photodamaged skin. For two weeks, volunteers were treated with estradiol three times every other day both on sun-protected areas near the hip and photodamaged skin on the forearm; a 4-millimeter biopsy (tissue sample) was taken from each therapy area 24 hours after the last therapy. Participants also applied estradiol, incorporated into moisturizing cream, to their faces twice per day during the two weeks. A 2-millimeter biopsy was taken from the crow's-foot area near the eye before and 24 hours after the last therapy......... Posted by: Emily      Read more         Source

September 14, 2008, 10:24 PM CT

Purifying parasites with light

Scientists have developed a clever method to purify parasitic organisms from their host cells, which will allow for more detailed proteomic studies and a deeper insight into the biology of organisms that cause millions of cases of disease each year.

A number of infectious pathogens, like those that cause Toxoplasmosis or Leishmaniases, have a complex life cycle alternating between free-living creature and cell-enclosed parasite. A thorough analysis of the proteins that help these organisms undergo this lifestyle change would be tremendously useful for drug or vaccine development; however, it's extremely difficult to separate the parasites from their host cell for detailed study.

As published in the September Molecular & Cellular Proteomics, Toni Aebischer and his colleagues worked around this problem by designing special fluorescent Leishmania mexicana (one of the a number of Leishmaniases parasites). They then passed infected cells through a machine that can separate cell components based on how much they glow. Using this approach, the scientists separated the Leishmania parasites with only about 2% contamination, far better than current methods.

They then successfully identified 509 proteins in the parasites, 34 of which were more prominent in parasites than free living Leishmania The results yielded a number of characteristics of these organisms, such as a high presence of fatty acid degrading enzymes, which highlights adaptation to intracellularly available energy sources. The identified proteins should provide a good data set for continued selection of drug targets, and the success of this method should make it a good resource for other cellular parasites like malaria......... Posted by: Emily      Read more         Source

September 11, 2008, 9:29 PM CT

About rural HIV care

An Indiana University study found that HIV care providers in rural Indiana report significant stigma and discrimination in the rural medical referral system surrounding issues of HIV and substance abuse. Providers felt that these factors impeded their ability to offer quality care to their patients.

"The findings of this study demonstrate inefficiencies in our public health care system and our inability to link people easily to a range of health care providers in rural areas," said Michael Reece, lead investigator of the study and director of The Center for Sexual Health Promotion in Indiana University Bloomington's School of Health, Physical Education and Recreation. "This also has an important economic impact given that our investments in the public health system may not be achieving the outcomes we need, such as improvements in health status."

While most studies involving HIV and stigma rely on patient perspectives, this study focused solely on the perspectives of providers serving rural Indiana residents. Providers reported that some rural physicians refused to provide care for their patients. They also reported widespread stigmatizing comments and behavior from the rural medical community.

The study, "HIV Provider Perspectives: The Impact of Stigma on Substance Abusers Living with HIV in a Rural Area of the United States," appears in the latest issue of the journal AIDS Patient CARE and STDs. For Reece, focusing research locally is important......... Posted by: Emily      Read more         Source

September 9, 2008, 8:57 PM CT

Calcium during pregnancy

Pregnant women who take high levels of daily calcium supplements show a marked reduction in lead levels in their blood, suggesting calcium could play a critical role in reducing fetal and infant exposure.

A new study at the University of Michigan shows that women who take 1,200 milligrams of calcium daily have up to a 31 percent reduction in lead levels.

Women who used lead-glazed ceramics and those with high bone lead levels showed the largest reductions; the average reduction was about 11 percent, said Howard Hu, chair of the Department of Environmental Health Sciences at the School of Public Health.

Hu is the principal investigator of the study and one of the senior authors on the paper, which is available online in Environmental Health Perspectives, the official journal of the U.S. National Institute for Environmental Health Sciences. Hu, who is also affiliated with the University of Michigan School of Medicine, said this is the first known randomized study examining calcium supplementation on lead levels in pregnant women.

"We and others have previously shown that during pregnancy, mothers can transfer lead from their bones to their unborn -- with significant adverse consequences--making maternal bone lead stores a threat even if current environmental lead exposures are low," Hu said. "This study demonstrates that dietary calcium supplementation during pregnancy may constitute a low-cost and low-risk approach for reducing this threat"......... Posted by: Emily      Read more         Source

August 31, 2008, 8:49 PM CT

Americans Show Little Tolerance for Mental Illness

A new study by University of Pennsylvania sociology professor Jason Schnittker shows that, while more Americans think that mental illness has genetic causes, the nation is no more tolerant of the mentally ill than it was 10 years ago.

The study published online in the journal Social Science and Medicine uses a 2006 replication of the 1996 General Social Survey Mental Health Module to explore trends in public beliefs about mental illness in America, focusing in particular on public support for genetic arguments.

Previous medical-sociology studies reveal that public beliefs about mental illness reflect the dominant mental-illness therapy, the changing nature of media portrayals of the mentally ill and the prevailing wisdom of science and medicine.

Schnittker's study, "An Uncertain Revolution: Why the Rise of a Genetic Model of Mental Illness Has Not Increased Tolerance," attempts to address why tolerance of the mentally ill hasn't increased along with the rising popularity of a biomedical view of its causes. His study finds that different genetic arguments have, in fact, become more popular but have very different associations depending on the mental illness being considered.

"In the case of schizophrenia, genetic arguments are linked to fears regarding violence," Schnittker said. "In fact, attributing schizophrenia to genes is no different from attributing it to bad character - either way Americans see those with schizophrenia as 'damaged' in some essential way and, therefore, likely to be violent. However, when applied to depression, genetic arguments have very different connotations: they are linked to social acceptance. If you imagine that someone's depression is a genetic problem, the condition seems more real and less blameworthy: it's in their genes, they're not weak, so I should accept them for who they are"......... Posted by: Emily      Read more         Source

August 31, 2008, 8:42 PM CT

Creating Blood By Identifying Earliest Stem Cells

Johns Hopkins scientists have discovered the earliest form of human blood stem cells and deciphered the mechanism by which these embryonic stem cells replicate and grow. They also found a surprising biological marker that pinpoints these stem cells, which serve as the progenitors for red blood cells and lymphocytes.

The biochemical marker, angiotensin-converting enzyme (ACE), is well known for its role in the regulation of blood pressure, blood vessel growth, and inflammation. ACE inhibitors are already widely used to treat high blood pressure and congestive heart failure, and the findings are, the scientists say, likely to hold promise for developing new therapys for heart diseases, anemias, leukemia and other blood cancers, and autoimmune diseases because they show for the first time that ACE plays a fundamental role in the very early growth and development of human blood cells.

"We figured out how to get the 'mother' of all blood stem cells with the right culture conditions," says Elias Zambidis, M.D., Ph.D., of the Institute of Cell Engineering at the Johns Hopkins University School of Medicine and the Division of Pediatric Oncology at the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins.

"There is real hope that in the future we can grow billions of blood cells at will to treat blood-related disorders, and just as critically if not more so, we've got ACE as a 'new' old marker to guide our work," Zambidis adds......... Posted by: Emily      Read more         Source

August 31, 2008, 8:29 PM CT

Master switch in the brain that regulates appetite and reproduction

Body weight and fertility have long known to be correlation to each other women who are too thin, for example, can have trouble becoming pregnant. Now, a master switch has been found in the brain of mice that controls both, and scientists at the Salk Institute for Biological Studies say it may work the same way in humans.

Findings from the study, published ahead of print in the Aug. 31 online edition of Nature Medicine, suggest that variations in the gene that produces this master switch, known as TORC1, could contribute a genetic component to obesity and infertility, and might be regulated with a novel drug.

"This gene is crucial to the daisy chain of signals that run between body fat and the brain," says Marc Montminy, Ph.D., a professor in the Clayton Foundation Laboratories for Peptide Biology, who led the study. "It likely plays a pivotal role in how much we, as humans, eat and whether we have offspring".

It is just as important as leptin, the well-known star regulator of appetite, Montminy says, because leptin turns on TORC1, which in turn activates many genes known to help control feeding and fertility.

Judith Altarejos Ph.D., first author on this study, had been trying to understand human energy balance, and what can go awry to promote obesity, diabetes and other metabolic syndromes. In this study, she looked at the signals that travel from body fat to the brain, informing the brain of how well fed the body is. The primary hormone that performs that function is leptin, which travels through the bloodstream to the hypothalamus in the brain (the appetite center), keeping the brain aware of the body's nutritional status......... Posted by: Emily      Read more         Source

August 27, 2008, 9:16 PM CT

Chronic stress alters our genetic immune response

Most people would agree that stress increases your risk for illness and this is especially true for severe long-term stresses, such as caring for a family member with a chronic medical illness. However, we still have a relatively limited understanding of exactly how stress contributes to the risk for illness. In the August 15th issue of Biological Psychiatry, scientists shed new light on one link between stress and illness by describing a mechanism through which stress alters immune function.

In a very promising preliminary study, Miller and his colleagues observed that the pattern of gene expression differed between caregivers of family members with cancer relative to a matched group of individuals who did not have this type of life stress. They observed that among the caregivers, even though they had normal cortisol levels in their blood, the pattern of gene expression in the monocytes, a type of white blood cell involved in the body's immune response, was altered so that they were relatively less responsive to the anti-inflammatory actions of cortisol, but relatively more responsive to pro-inflammatory actions of a transcription factor called nuclear factor-kappa B, or NF-κB. Gregory Miller, Ph.D., corresponding author, explains more simply that, eventhough "caregivers have similar cortisol levels as controls, their cells seem to be 'hearing' less of this signal. In other words, something goes awry in caregivers' white blood cells so they are not able to 'receive' the signal from cortisol that tells them to shut down inflammation"......... Posted by: Emily      Read more         Source

August 27, 2008, 9:12 PM CT

Genetic predisposition may play a role in anxiety disorders

Finnish researchers have identified genes that may predispose to anxiety disorders. Research conducted under the supervision of Academy Research Fellow Iiris Hovatta have focused on genes that influence human behaviour, and some of the studied genes show a statistical association with specific anxiety disorders. The work is carried out as part of the Academy of Finland Research Programme on Neuroscience (NEURO).

Previously Hovatta's team have explored the genetic background of anxiety in experimental models. The current study follows up on these findings in humans using data collected as part of national Health 2000 Survey consisting of 321 individuals who had been diagnosed with anxiety disorder and 653 healthy controls. Hovatta says it was interesting that different genes showed evidence for association to specific types of anxiety disorders, such as panic disorder, social phobias or generalised anxiety disorder. The results will be published in Biological Psychiatry in October.

"Environmental factors, such as stressful life events, may trigger an anxiety disorder more easily in people who have a genetic predisposition to the illness," Iiris Hovatta says. The focus in the team's further studies will be to understand the molecular and cellular processes that link these genes to the regulation of anxiety behaviour......... Posted by: Emily      Read more         Source