July 26, 2007, 4:53 AM CT

Can the tonsils influence oral HIV transmission?

Bethesda, MD Current research demonstrates that the tonsils may possess the necessary factors to act as a transmission site for the spread of HIV. The related report by Moutsopoulos et al, Tonsil Epithelial Factors May Influence Oropharyngeal Human Immunodeficiency Virus Transmission, appears in the recent issue of The American Journal of Pathology.

Human immunodeficiency virus (HIV) spreads mainly through sexual contact of mucosal surfaces, which the virus must cross to come in contact with underlying immune cells for infection to occur. While the oral mucosal surfaces are largely protected by their thickened exterior and the defensive proteins present in saliva, it is speculated that a low number of infections may occur via oral sexual contact. Scientists have questioned whether such transmission is facilitated by the tonsils, which contain high numbers of immune cells that may be easily accessible to HIV.

Scientists led by Dr. Sharon M. Wahl, of the National Institute of Dental and Craniofacial Research, NIH, examined this question by comparing the gene expression profiles of tonsils and oral gingiva. Eventhough a number of of the genes examined showed similar expression patterns between the two oral sites, differences were observed. Notably, several genes correlation to immune functions, including HIV co-receptor CXCR4, displayed significantly higher expression in the tonsils while gingiva more strongly expressed keratin genes, which thicken the tissue and provide barrier protection......... Posted by: Emily      Read more         Source

July 25, 2007, 5:14 AM CT

Research On Fixational Eye Movements

Susana Martinez-Conde, Ph.D., director of the Laboratory of Visual Neuroscience, and Stephen Macknik, Ph.D., director of the Laboratory of Behavioral Neurophysiology at Barrow Neurological Institute at St. Josephs Hospital and Medical Center, are featured on the cover of the recent issue of Scientific American for their research on fixational eye movements. The pair was also featured in a recent issue of the Wall Street Journal.

Scientific American is considered by a number of to be the Rolling Stone magazine of science, says.

Dr. Macknik. It is a honor in our career to be featured in such a prestigious publication.

Drs. Martinez-Conde and Macknik authored an article describing the history of fixational eye movement research and the investigations they have conducted at Barrow. For decades, scientists have debated the purpose of fixational eye movements and especially of microsaccades, the largest and fastest of fixational eye movements. Recent research conducted by Dr. Martinez-Conde and her team at Barrow has shown that microsaccades produce visibility when a persons gaze is fixed on an object. Microsaccades may also help reveal a persons subliminal thoughts. Fixational eye movements are responsible for driving most of our visual experience and without them humans would become blind to stationary objects......... Posted by: Emily      Read more         Source

July 25, 2007, 5:08 AM CT

curing injured spinal cord

Research on rats with crushed spinal cords, similar to human injury, reveals that therapy soon after injury combining radiation treatment to destroy harmful cells and microsurgery to drain excess fluids significantly increases the bodys ability to repair the injured cord leading to permanent recovery from injury, as per the study reported in the July 18 peer-evaluated journal PLoS ONE. Since repair of damaged cord directly correlates with prevention of paralysis, this research demonstrates that conventional clinical procedures hold promise for preventing paralysis from spinal cord injuries.

Currently there is no cure for human spinal cord injury. Treatment after injury is largely limited to steroids administered to prevent further deterioration. This research opens the door to developing a clinical protocol for curing human spinal cord injuries using conventional therapies, said lead researcher Nurit Kalderon, Ph.D. Conducted at Sloan-Kettering Institute for Cancer Research in New York City, the research was supported by a grant from the National Institute of Neurological Disorders and Stroke (NINDS).

The hallmark of spinal cord injury is progressive tissue decay at the damage size. Kalderon's prior research indicated that the spinal cord is able to repair itself in the early days after injury but is thwarted in its efforts during the second or third week by certain cells that block the repair process......... Posted by: Emily      Read more         Source

July 25, 2007, 4:59 AM CT

Treating HIV-infected infants early

Hundreds of thousands of babies around the world are born each year with HIV--more than half a million in 2006 alone. Caring for these children is complicated by the fact that their immune systems are not fully developed in the first year of life, which makes them particularly susceptible to rapid HIV disease progression and death. The current standard of HIV care in a number of parts of the world is to treat infants with antiretroviral treatment--but only after they show signs of illness or a weakened immune system.

Now the initial results of an ongoing clinical trial sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), suggests that more HIV-infected infants survive if they are given treatment early on, regardless of their apparent state of health.

This trial, called the Children with HIV Early Antiretroviral Therapy (CHER) study, is a phase III, randomized clinical trial led by Avy Violari, M.D., FCPaed (SA), of the University of the Witwatersrand in Johannesburg, South Africa, and Mark Cotton, MBChB, MMed, of the University of Stellenbosch in Cape Town, South Africa. Dr. Violari will present these findings on Wednesday, July 25 at the 2007 International AIDS Society Conference in Sydney, Australia......... Posted by: Emily      Read more         Source

July 23, 2007, 6:48 PM CT

Medical students respond positively to simulated patient experience

When a vomiting, simulated patient mannequin was rolled into the lecture hall last fall to teach large numbers of first- and second-year Wake Forest University School of Medicine students about the brain and nervous system, Michael T. Fitch, M.D., Ph.D., wasnt sure what to expect.

In the end, he got the results he was looking for. I really didnt know what it was going to look like when I started, said Fitch, an emergency medicine specialist who developed the teaching scenario and conducted a pilot study to determine the simulations success in a non-traditional location with a large number of participants. The research is published online today in Medical Teacher and will appear in the August print issue.

It was hard to do and we really wanted to engage the students, said Fitch.

High fidelity patient simulation of this kind has typically been done with small groups to teach clinical patient management and decision-making. What Fitch found through his student survey results is that it was well received in the large lecture setting.

Students were overwhelmingly positive and the results will lead to future study of program expansion, he said. Survey results showed that 98 percent of participants rated the related to basic science concepts as very good or outstanding, and 99 percent felt the same way about the presentation......... Posted by: Emily      Read more         Source

July 23, 2007, 6:45 PM CT

Childhood sun exposure may lower risk of MS

People who spent more time in the sun as children may have a lower risk of developing multiple sclerosis (MS) than people who had less sun exposure during childhood, as per a research studyreported in the July 24, 2007, issue of Neurology, the medical journal of the American Academy of Neurology.

For the study, scientists surveyed 79 pairs of identical twins with the same genetic risk for MS in which only one twin had MS. The twins were asked to specify whether they or their twin spent more time outdoors during hot days, cold days, and summer, and which one spent more time sun tanning, going to the beach and playing team sports as a child.

The study found the twin with MS spent less time in the sun as a child than the twin who did not have MS. Depending on the activity, the twin who spent more hours outdoors had a 25 to 57 percent reduced risk of developing MS. For example, the risk of developing MS was 49 percent lower for twins who spent more time sun tanning than their siblings.

Sun exposure appears to have a protective effect against MS, said study authors Talat Islam, MBBS, PhD, and Thomas Mack, MD, MPH, with the Keck School of Medicine of the University of Southern California in Los Angeles. Exposure to ultra violet rays may induce protection against MS by alternative mechanisms, either directly by altering the cellular immune response or indirectly by producing immunoactive vitamin D......... Posted by: Jessica      Read more         Source

July 23, 2007, 6:33 PM CT

Poor health literacy in the elderly

Elderly adults who cannot read and understand basic health information appear to have increased mortality rates over a five-year period than those with adequate health literacy, as per a report in the July 23 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.

Education, as measured by the number of years of school completed, has been associated with longer life, as per background information in the article. This may be because more education tends to result in better job opportunities, a higher annual income and access to housing, food and health insurance. Another possible mechanism by which education could exert a direct effect on health is reading fluency, the authors write. The number of years of school completed is strongly linked to reading fluency. As a result, individuals with more education tend to have a better capacity to obtain, process and understand basic health information and services needed to make appropriate health decisions: i.e., they have higher levels of health literacy.

David W. Baker, M.D., M.P.H., of Northwestern University Feinberg School of Medicine, Chicago, and his colleagues interviewed 3,260 Medicare patients age 65 and older in four metropolitan areas in 1997, asking questions about demographics and health. Participants also completed a test of health literacy that involved two reading passages and four mathematical items. Scores range from zero to 100, with zero to 55 designating inadequate health literacy, 56 to 66 indicating marginal health literacy and 67 to 100 signifying adequate health literacy. The National Death Index was then used to identify participants who died through 2003......... Posted by: Emily      Read more         Source

July 23, 2007, 5:46 PM CT

Influenza and measles vaccinations in HIV-infected patients

Two new studies emphasize the importance of delivering measles and influenza vaccines to HIV-infected individuals. Both studies are reported in the August 1 issue of The Journal of Infectious Diseases, now available online.

William J. Moss, MD, and his colleagues at the Johns Hopkins University and elsewhere studied immune responses to measles vaccine in HIV-infected and uninfected children in Zambia from 2000 to 2004, when measles endemic in a country that still has one of the highest HIV prevalence rates in the world. Measles poses a greater fatality risk in HIV-infected children than in uninfected children.

Measles vaccine was administered in both groups at age 9 months. This is the age recommended for infants who are not HIV-infected, but it is usually also the age when HIV-infected infants are vaccinated against measles. Children were followed for up to 27 months thereafter. Some received repeat vaccination. Measles-specific antibodies in the blood were then measured on subsequent visits.

Dr. Moss and his colleagues observed that eventhough 88 percent (44 of 50) of HIV-infected children developed protective antibody levels within 6 months of vaccination, during 27 months of follow-up only half of the [18] HIV-infected children who survived maintained protective antibody levels, compared with almost 90 percent [63 of 71] of the HIV-uninfected children. In contrast, 92 percent (11 of 12) of HIV-infected children who were vaccinated a second time during follow-up had protective antibody levels......... Posted by: Emily      Read more         Source

July 23, 2007, 5:28 PM CT

Ethnicity plays a role in neonatal deaths

Scientists have uncovered ethnic differences in the risk of neonatal mortality and morbidity (disease) in the neonatal intensive care units (NICU). Of grave concern is the noted elevation in mortality rate in the NICU among infants of South Asian (East Indian) origin, which is over three times that of Caucasian infants. It was also observed that Aboriginal males and East Asian females had significantly greater odds of survival.

Interestingly, small for gestational age was noted as a significant factor only among Caucasian infant, while only gestational age less than 29 weeks was found to be a significant risk across all ethnic groups.

Understanding these differences is important so we can determine what specific areas to target in order to improve health-care delivery and reduce these disparities, said Dr. Shoo Lee, Scientific Director of iCARE at the University of Alberta.

As the number of premature births in North America has increased over the last 20 years, questions have emerged about how best to care for newborns and their mothers, especially in immigrant populations where inequalities in health outcomes may already exist.

In the United States, prematurity has been reported as the leading cause of neonatal death among African-American newborns, but the research team has observed that neonatal sepsis (infection) was the strongest predictor of mortality among African-American infants, even greater than being born at 28 weeks of age or younger......... Posted by: Emily      Read more         Source

July 19, 2007, 10:37 PM CT

Manic Depression And Brain Tissue Loss

People with bipolar disorder or manic depression suffer from an accelerated shrinking of their brain, scientists at the University of Edinburgh have found.

The study shows for the first time that bipolar disorder a condition characterised by periods of depression and periods of mania is linked to a reduction in brain tissue and proves that the changes get progressively worse with each relapse.

This discovery has implications not only for the way we research the disease, but may also impact the way this condition is treated.

The findings, reported in the Journal of Biological Psychiatry, show that the loss of grey matter tissue is concentrated in areas of the brain which control memory, face recognition and co-ordination namely the hippocampus, fusiform and cerebellum respectively.

Dr. Andrew McIntosh, senior lecturer in psychiatry and lead researcher, said: For the first time, we have shown that as people with bipolar disorder get older, a small amount of tissue is lost in parts of the brain that are linked to memory and the coordination of thoughts and actions. The amount of brain tissue thats lost is greater in people with multiple episodes of illness and is linked to a decline in some areas of mental ability.

Eventhough we do no yet know the cause of this brain shrinkage, it may be that repeated episodes of illness harm the brain and lead to the decline. Another possibility is that the brain changes are caused by stress or genetic factors, which tend to lead both to more frequent illness episodes and to greater brain loss. Further research will be required......... Posted by: Emily      Read more         Source