August 6, 2006, 10:32 AM CT

Why Reassurance Fails in Patients with Unexplained Symptoms

Our results show that patients with unclear medical symptoms overestimate the likelihood of medical causes of symptoms. Although in the medical report the doctor rejected most of the mentioned medical explanations for the symptoms, the patients with unclear somatic complaints remembered higher probabilities for these medical explanations. The mean estimates of the somatization patients for the likelihood of medical explanations were about 15%, which is not very high, but still suggests that the patients had not discarded the medical causes as a possibility. Patients with medically unexplained symptoms might have a tendency to overestimate the risk of diseases in general, as was found for hypochondriasis [20,21]. This tendency might be maintained by further remembering increased likelihood estimates for medical causes. As our clinical group included only four (of 33) patients with hypochondriasis, the reported effects are not completely determined by this small subgroup, but also hold for somatization syndrome in general.

Our results are all the more striking because our items about the likelihood of explanations were not related to the patient's personal situation, but to a virtual situation. This bias in remembering likelihood estimates was only found for the medical report situation, not for the social or neutral situations. Amazingly, this effect was even more pronounced for the unequivocally rejected medical explanations, compared to the unlikely, but marginally probable, explanations.........

Posted by: Rose      Permalink         Source

August 6, 2006, 0:00 AM CT

Broad Talk Illuminates Genetics

For decades, researchers have been teasing out the secrets of the human genome, hoping to learn more about what makes the body function and why things sometimes go wrong.

Now, researchers are on the brink of identifying genes that play a major role in a variety of diseases, thanks to recent rapid advances in DNA sequencing technology, as per Dr. David Altshuler, director of the program in medical and population genetics at the Broad Institute of MIT and Harvard.

Altshuler talked about "expectations for improved therapies in the era of genomic medicine" at the final installment of the "Midsummer Nights' Science" lecture series held at the Broad Institute on Aug. 1.

Scientists at the Broad and around the world are using new sequencing technology to look for genes that are associated with the development of diseases such as diabetes, multiple sclerosis, lupus, bipolar disorder and autism, among a number of others.

The new research builds on the 2003 completion of the human genome sequence, which showed that while most humans share the vast majority of their genetic sequence (about 99.9 percent), variations known as single nucleotide polymorphisms, or SNPs, occur within the other.1 percent of the genome. Those variations are what make each individual unique.........

Posted by: Jessica      Permalink         Source

August 2, 2006, 11:33 PM CT

Mapping System For Skin Cells

Global-positioning system aficionados know that it's possible to precisely define any location in the world with just three geographic coordinates: latitude, longitude and altitude. Now scientists at the Stanford University School of Medicine have discovered that specialized skin cells use a similar mapping system to identify where they belong in the body and how to act once they arrive.

These cellular cornerstones direct embryonic patterning and wound healing by sending vital location cues to their neighbors, and may help in growing tissue for transplant or understanding metastatic cancer.

"There is a logic to the body that we didn't understand before," said John Rinn, PhD, a postdoctoral scholar in the laboratory of Howard Chang, MD, PhD, assistant professor of dermatology. "Our skin is actively maintaining itself throughout our life, and these 'address codes' help the cells know how to respond appropriately." Rinn is the first author of the research, which is published in the current issue of Public Library of Science-Genetics.

Until now it's been a mystery as to how adult skin, which consists of basically the same components all over the body, knows to grow hair in some areas like the scalp, while manufacturing sweat glands, calluses and fingerprint whorls in others. In 1969, well-known developmental biologist Lewis Wolpert authored a famous treatise that described two possible ways for cells to know where they are in the body: Either they infer their location and adjust their behavior based on interactions with nearby cells, or they deduce their "positional identity" through the use of some type of coordinate system. The findings from the new Stanford study bolster the second possibility.........

Posted by: Rose      Permalink         Source

August 2, 2006, 8:27 PM CT

Core Verbal Autopsy Procedures

The increasing importance of VA is reflected in the growing number of meta-analyses of VA-based datasets on child mortality from demographic surveillance sites and special studies [4–6,45], all of which make the case for standardized procedures. The procedures presented here are the product of over a decade of application, trial, assessment, and refinement, and have considerable commonalities with other forms in the public domain.

The main purpose of these tools is to supply countries that have no source of reliable mortality reporting and cause-of-death data with the means to confidently produce and use accurate, repeatable, and internationally comparable measurements of the cause structure of mortality for the most important diseases and conditions, and that are free from major systematic misclassification. To be sure, VA is a crude substitute for proper medical certification of cause of death—which can be a dubious “gold standard” even in developed countries [50]. The Tanzania–China experience has shown that the transfer of this technology from one setting to another is feasible and can produce results with acceptable sensitivity and CSMFs for important causes of death. In wider application, local validation studies should be considered an essential part of implementing VA procedures intended for national monitoring, evaluation, priority-setting, and policy-making.........

Posted by: Rose      Permalink         Source

August 1, 2006, 11:28 PM CT

Confusion, Not Stress

Even though they are trained in CPR, people hesitate to take action when an emergency unfolds in front of them. But the cause, a study has found, is more likely to be confusion than stress.

A study conducted by several researchers surveyed 1,243 lay people trained in CPR (cardiopulmonary resuscitation) who took part in a clinical trial. Most of them said they experienced low stress levels when faced with responding to a person in medical distress. "Most lay responders did not view the experience as onerous, but there are people who had negative experiences," said Dr. David Feeny, a professor of Public Health Sciences at the University of Alberta, Edmonton, Canada, and one of the co-authors on the study. Also contributing to the study were researchers from the University of Pennsylvania, University of Pittsburgh, University of Washington, as well as medical workers and health centres.

The study was published recently in the journal Resuscitation.

Random cardiac arrest is a leading cause of death in North America and lay responder CPR rates remain low.

Respondents did indicate that practical issues such as crowd control and skill performance concerned them more than their emotions. Concerns included barriers to responding such as communication with confused and combative patients; skills such as accessing airways or taking accurate pulse checks; accessing the victim in awkward, dark or cramped areas; harnessing their own feelings of panic; and dealing with the characteristics of the victim, such as bleeding, jerking, vomiting, age and size.........

Posted by: Rose      Permalink         Source

August 1, 2006, 8:22 PM CT

Abnormal Cortical Development after Premature Birth

Nowadays, many children who are born prematurely can be expected to survive. However, children who are born very prematurely have a high chance of having brain damage that leads to delayed development compared with children of the same age but who were not born prematurely. This delay continues into school age at least and is worse in boys than in girls. Although some children have large obvious areas of brain damage, shown on brain scans, most do not and the changes that cause the delay must be more subtle. One possibility is that the underlying abnormality may be due to the fact that in these children the surface of the brain grows at too slow a rate compared to the volume of the brain. It is already known that the human brain (and the brain of closely related monkeys) has a very high surface area compared to its volume and that during normal development this surface area grows much faster than the volume. This extra growth appears to be necessary for the brain to make all the connections it needs.

Why Was This Study Done?

The researchers wanted to look at how the different parts of the brain grew in very premature babies born before 30 weeks (the normal time of gestation is around 40 weeks). In particular, they wanted to see if there were changes in the rates at which the different parts of the brain grew in relation to each other (the study of the change in proportion of various parts of an organism as a consequence of growth is known as Allometrics—hence the title of the paper). They then wanted to see if the rates of brain growth were affected by a variety of factors, including the sex of the baby or how premature he or she was, and whether there was a relationship between the rate of brain growth and later delayed development.........

Posted by: Rose      Permalink         Source

July 31, 2006, 10:32 PM CT

An Eye-opening Look At Anesthesia

Raise your hand if you are more afraid of the prospect of general anesthesia than of surgery itself. If you raised your hand, you are not alone, according to the newest faculty member at the Harvard-MIT Division of Health Sciences and Technology (HST).

Dr. Emery N. Brown, who explores what happens to the brain during anesthesia, began a dual appointment as professor of health sciences and technology and professor of computational neuroscience in the Department of Brain and Cognitive Sciences (BCS) at MIT in October 2005.

"Anesthesia has taken on a mythical quality; it's not perceived as a neuro-physiological phenomenon," he said.

He describes the motivation behind his current research focus: "For many years, I was practicing anesthesiology, learning clinical skills in order to take care of patients, not thinking about how anesthesia affects patients. Then 10 years ago, when HST alum Dr. Greg Koski was the head of human studies at MGH, he said, 'It would be interesting to see an image, to see what happens when someone is under anesthesia.'" Brown was hooked.

"We say we induce anesthesia and then 'wake up' the patient," Brown said. "But in French the patient is reanime, or brought back to life. We haven't yet begun to think precisely about what we do, however. Anesthesia is not like sleep. It's not the same process".........

Posted by: Rose      Permalink         Source

July 29, 2006, 8:14 PM CT

meditation and cognitive impairment

Scientists at the University of Pennsylvania School of Medicine are examining the effectiveness of meditation on early cognitive impairment. Once this new study is completed, the results could help answer lingering questions over whether or not stress-reducing techniques and mind exercises can lessen or even prevent cognitive decline. This is the first study at Penn's new "Center for Spirituality and the Mind," which evolved from work initiated in Penn's Department of Radiology to embrace and encourage scientists from the fields of medicine, pastoral care, religious studies, social work, nursing, and bioethics to expand our knowledge of how spirituality may affect the human brain.

"We'll be looking at patients with mild cognitive impairment or symptoms of early Alzheimer's disease," explains Andrew Newberg, MD, Associate Professor of Radiology, Psychiatry, and Religious Studies, who also directs the Center's investigations and is Principal Investigator of this pilot study. "We'll combine their meditation with brain imaging over a period of time to see if meditation improves cognitive function and is linked to actual change in the brain's activity levels. Specifically, we'll be looking for decreased activity in specific areas of the brain".

The dementia process causes a decreased function of neurons in the brain and can result in problems with memory, visual-spatial tasks, and handling emotional issues. As it worsens in a patient, it can also eventually lead to the need for round-the-clock care.........

Posted by: Rose      Permalink         Source

July 28, 2006, 10:16 PM CT

River Blindness Treatment

Onchocerciasis, river blindness or craw craw is an endemic disease in Bioko Island, Equatorial Guinea. This pathology causes a weakening in affected individuals, most of them within the labour force population, making this disease one of the limiting factors for the economic development of the island. Onchocerciasis is caused by the worm Onchocerca volvulus. It is transmitted through the bite of the black fly, Simulium. Enviromental conditions such as humidity, rapid water rivers and altitude of Bioko favour the development of this pathology, since this is the habitat of the fly acting as a vector. The parasite, in the form of larve, is inoculated to humans when the fly bites humans to obtain blood. Female parasites measure 30 to 50 cm and live 10 to 15 years, whereas male parasites measure 3 to 5 cm. Worms form tumours in infected indivuduals, and some of them are easily visible. Fecunded females emit daily 1,200 larves (microfilaria) measuring 150-360 micras, which are disseminated through the host's skin, eyes and other organs. Affected individuals can host 50-200 million worms, particularly distributed in skin and eyes, commonly provoking blindness.

The work, carried out by the group of Hospital Clínic de Barcelona, was led by Dr. Jordi Mas of the Microbiology Unit of Hospital Clínic-Universitat de Barcelona, and Dr. Carlos Ascaso of the IDIBAPS Epidemiology and International Health Research Group. The objective of this study was to assess the impact of 8-year vertical distribution of Ivermectin, the only therapy available against onchocerciasis, among the rural population of 12 communities and two ethnical groups: the Bubis and the Fangs. The fact that the administered drug dose is only effective on larves, conditions the duration of this study. The study was carried out during 8 years, because this is precisely the maximum time of fertility of females, what guarantees the total elimination of the offspring.........

Posted by: Rose      Permalink         Source

July 28, 2006, 10:04 PM CT

Peaks And Troughs Of Dengue Epidemics

Scientists have long known that epidemics of dengue fever wax and wane over a period of several years, but they've never been quite sure why. With the incidence and range of the potentially deadly mosquito-borne illness increasing, understanding the factors that influence these epidemics has never been more important.

A new study by researchers at the University of Georgia suggests that a brief period of cross-immunity conferred by any one of the four viral strains, or serotypes, that cause dengue explains the timing of epidemics.

"We found that since about the mid 1980s, there's been a sequential replacement of the dominant serotype," said lead author Helen Wearing, a post-doctoral researcher at the UGA Institute of Ecology. "So, for example, one year serotype three is 60 percent of the cases and the next year serotype two is dominant and so on. Epidemics of individual serotypes recur every eight to 10 years, but, at the same time, if you look at all the data together, you see about an average three-year cycle with some seasonal component to it".

In addition to helping resolve a long-standing debate in public health, the study, published this week in the early online edition of the journal Proceedings of the National Academy of Sciences, gives researchers a framework that can be used to create models that predict dengue outbreaks in both space and time.........

Posted by: Rose      Permalink         Source

Older Blog Entries   Older Blog Entries   1   2   3   4  

---