December 16, 2005

Cell-based Nano Machine

Scientists have known for some time that a long, fibrous coil grown by a single-cell protozoan is, gram for gram, more powerful than a car engine. Now, scientists at Whitehead Institute-together with colleagues at MIT, Marine Biological Laboratory in Woods Hole, MA, and University of Illinois, Chicago-have found that this coil is far stronger than previously thought. In addition, the scientists have discovered clues into the mechanism behind this microscopic powerhouse.

"These findings are twofold," says Danielle France, a graduate student in the lab of Whitehead Member Paul Matsudaira, and, along with Matsudaira, a member of MIT's Division of Biological Engineering. "First, they give us an idea of how a cell can manage to generate such enormous force; and second, they provide clues for how engineers might reconstruct these mechanisms for nano-scale devices."

France will present her findings Sunday, December 11, at the 45th Annual Meeting of the American Society for Cell Biology in San Francisco.

Researchers have known about this nano-spring for roughly 300 years, ever since Anton van Leeuwenhoek first observed the protozoan, Vorticella convallaria, through a hand-made microscope. The spring in the unicellular Vorticella is a contractile fiber bundle, called the spasmoneme, which runs the length of the stalk. At rest, the stalk is elongated like a stretched telephone cord. When it contracts, the spasmoneme winds back in a flash, forming a tight coil. To find out how strongly Vorticella recoils, France and his colleagues used a unique microscope to apply an extra load to the spring. The microscope, developed by Shinya Inoue and his colleagues at the Marine Biological Laboratory in Woods Hole, MA, uses a spinning platform to increase the centrifugal force exerted against the protozoan.........

Scott      Permalink


December 16, 2005

Tongue Sensors Taste Fat

As you stand at buffet tables during holiday parties this year, it might cheer you up to know most people don't gain as much weight over the holidays as once was thought. Instead of five or 10 pounds, most of us actually gain only a pound or two. But it might depress you to know that weight gain happens one pound at a time and in the long run, it may be hard to avoid - particularly for some of us, because some of the taste buds in our tongues are programmed to make us crave fatty food - and fat is everywhere in our diets.

French scientists recently reported that mice have a receptor in their tongues that can sense fat, and the presence of that receptor seems to drive the mice to crave fat in their diets. The work was based on research from Nada A. Abumrad, Ph.D., the Dr. Robert C. Atkins Professor of Medicine and Obesity Research at Washington University School of Medicine in St. Louis. She previously had identified a protein receptor for fat and documented its function in recognizing and using fatty food. This led the French scientists from the Taste Institute in Dijon, France, to wonder whether the protein also may have a role in actually tasting fat.

"Fat sensing has been very controversial," Abumrad says. "It once was thought that we could sense five different tastes: sweet, salty, sour, bitter and what researchers refer to as umami, which is the taste of a protein like monosodium glutamate. There was some indirect evidence that the tongue might be able to identify fat, too, but a number of researchers thought that involved sensation of texture more than the actual taste of fat."

Abumrad adds that several researchers had proposed people might not only sense the texture of fat, but also might have fatty acid receptors that lead them to prefer foods containing fat. She studies the molecular mechanisms regulating utilization of fatty acids, and she was the first to identify a protein called CD36 that facilitates the uptake of fatty acids. The CD36 receptor protein is located on the surface of cells and distributed in a number of tissues, including fat cells, the digestive tract, heart tissue, skeletal muscle tissue and, as it happens, the tongue.........

Daniel      Permalink


December 16, 2005

Strategy To Knock Out Cancer

To remain healthy, all cells must quickly mend any breaks that arise in their DNA strands. But cancer cells are especially dependent on a process called homologous recombination to repair DNA and stay alive.

Now scientists at Washington University School of Medicine in St. Louis have found that a protein known as MDC1 has a role in homologous recombination. This discovery could be exploited in a two-pronged therapy strategy to eliminate cancer cells' ability to repair DNA.

"Frequently cancer cells are more efficient at DNA repair than normal cells," says Simon Powell, M.D., Ph.D., head of the Department of Radiation Oncology and a researcher with the Siteman Cancer Center at Washington University School of Medicine and Barnes-Jewish Hospital. "That's what makes them resistant to drugs or radiation therapys that physicians use in an effort to damage cancer cells' DNA and destroy them."

But in light of their findings, Powell and colleagues believe MDC1 - along with other proteins involved this repair pathway - may be good targets for dual-drug chemotherapeutic approaches that can completely knock out tumor cells' ability to cope with DNA damage. Their study appears in the recent issue of Nature Structural and Molecular Biology.

The research group discovered that MDC1, a protein previously recognized only for its function in sensing DNA damage and signaling its presence, also transports DNA-repair proteins to the site of DNA strand breaks. Without MDC1 to pave the way, repair happens slowly because the fix-it proteins have a hard time reaching damaged areas, which are buried in the tightly packed chromosomal material of the cell's nucleus.

"MDC1 can bind to chromatin, the complex mixture of DNA and proteins that holds the genetic material," Powell says. "Because of chromatin's properties, getting into it to reach the DNA strand requires the right 'passwords.' MDC1 provides the DNA-repair proteins with this privileged access, and efficiently transports them to the site of damage so they can do their jobs."........

Daniel      Permalink


December 16, 2005

Type 2 Diabetes And Depression

Type 2 diabetes and depression can be a fatal mix. Patients whose type 2 diabetes was accompanied by minor or major depression had higher mortality rates, compared to patients with type 2 diabetes alone over the three-year period of a recent study in Washington state. The results appear in the November 2005 edition of Diabetes Care, published by the American Diabetes Association.

Scientists at the University of Washington and at Group Health Cooperative, a large, Seattle-based health plan, conducted the study. The scientists surveyed and followed up 4,154 patients with type 2 diabetes. The patients filled out written questionnaires. With patients' consent, automated diagnostic, laboratory, and pharmacy data were collected from Group Health Cooperative. The scientists also reviewed Washington state mortality data to analyze diabetes complications and deaths.

Depression is common among people who have type 2 diabetes. This high prevalence can have unfortunate repercussions. Both minor depression and major depression among people with diabetes are stongly linked with increased mortality.

"Depression may be associated with increased mortality in patients with diabetes because of both behavioral and biological factors," the scientists noted in their article. More work, they added, is needed to untangle the cause-and effect relationships among depression, behavior, diabetes complications, and mortality.

Dr. Wayne Katon, professor and vice chair of the UW Department of Psychiatry and Behavioral Sciences, and an adjunct professor in the UW Department of Family Medicine, led the recent study. He is a noted researcher on the associations between depression, aging, and chronic diseases, and on the medical costs and personal toll from untreated on inadequately treated depression. The research team included Drs. Carolyn Rutter, Greg Simon, Elizabeth Lin, Evette Ludman, and Michael Von Korff from the Group Health Cooperative Center for Health Studies; Dr. Paul Ciechnowski, UW assistant professor of psychiatry and behavioral sciences; Dr. Leslie Kinder from the Veterans Affairs Puget Sound Health Care System; and Dr. Bessie Young from the UW Department of Medicine.........

JoAnn      Permalink


December 16, 2005

Microbial Choreography

Birds fly together in flocks. Fish swim together in schools. Everyone has seen the beautiful, seemingly choreographed motions these collections of organisms can exhibit.

But surely bacteria, which have no eyes or brain, cannot behave in such a coordinated way. In fact, they do, and scientists are beginning to learn how.

Bacteria are well known to interact with one another through chemical signals - they can "smell" one another, and their behavior and growth may change if they have a number of neighbors. Chemical signaling between bacteria enables cooperative behavior of a bacterial population; one example of this is "cell swarming," where colonies of bacteria grown in a petri dish form complex and beautiful patterns.

More recently, experiments in several laboratories have shown that bacteria swimming in a drop of water also form patterns-jets and whirls that are much larger than the bacteria themselves, and that stir the fluid in ways that an individual swimming bacterium cannot. A key question then is: How do the swimming bacteria interact to form these patterns? .

Reporting in the November 11 issue of Physical Review Letters, Chemical and Biological Engineering Professor Mike Graham's group at the University of Wisconsin-Madison developed a model that offers a partial answer to this question. In this model, each bacterium pushes fluid around as it swims, and simultaneously is buffeted like a boat on a wavy sea by the fluid motions generated by all the other swimming bacteria.

View the depiction of the model online.

There are no other interactions between the bacteria in this model: They cannot smell, feel or see one another, says Graham. This model might be expected to just predict random, uncoordinated swimming of the bacteria, and indeed at low concentrations this is exactly what occurs.........

Mark      Permalink


December 16, 2005

New Recommendations for Use of Artificial Nutrition and Hydration

For two decades, doctors have followed an ethically-established agreement about the appropriate use of artificial nutrition and hydration (ANH) for patients who are seriously ill or in a persistent vegetative state. Generally, patients or their surrogates have been able to accept or refuse ANH based upon considerations that guide most therapy decisions, i.e., potential benefits, risks, burden, religious and cultural beliefs. The Terri Schiavo case - which included very open, dramatic disagreements among family members over such considerations - publicly challenged long-held agreements about ANH and caused a number of to question its proper use.

In response to such challenges, scientists from the University of Pennsylvania's Institute on Aging and Center for Bioethics, and the Philadelphia VA's Center for Health Equity Research and Promotion review and clarify ethical principles regarding the use of ANH. According to the authors, the five ethical principles that should guide decisions about ANH are: .

Decisions about the use of ANH should be made in the same way that decisions about other medical therapy are made.

The same ethical reasoning applies whether withholding or withdrawing ANH.

Decisions on the patient's behalf require the same evidence of the patient's preferences as is mandatory for other significant therapy decisions.

Decisions about ANH may be made without any evidence of the patient's preferences.

All Patients should receive high quality palliative care regardless of whether they receive ANH.

These recommendations are the result of a national conference held at the University of Pennsylvania in early 2005, and appear in the December 15th, 2005 issue of the New England Journal of Medicine.........

Sue      Permalink


December 16, 2005, 9:15 PM CT

Cause Of Breathing Problems In Rett Syndrome Children

A multi-institutional team, led by University of Chicago researchers, has taken a crucial step toward understanding and treating Rett syndrome (RS), a rare and often misdiagnosed neurodevelopmental disorder that affects 1 in 10,000 children, mostly females.

As per a research findings published in the December 14, 2005, issue of the Journal of Neuroscience, the scientists describe in a mouse model for RS the source of erratic breathing, which has important implications for children with RS.

Along with breathing problems, RS causes slowed brain and head growth, mental retardation, seizures, gait abnormalities, and handwringing.

"It is absolutely tragic for the family," said Jan-Marino Ramirez, professor of organismal biology and anatomy at Chicago and lead author of the paper. "It's a progressive disease that shows no mercy".

In order to study the breathing pattern more closely, Ramirez and his team showed that mice with the RS gene exhibit the same behavior as children: They breathe irregularly and stop breathing often.

According to Ramirez, one hypothesis that has dominated the thinking of a number of clinicians is that the erratic breathing is due to cortical problems. "It's as if they want to stop breathing," he said. "Some clinicians went that far to suggest that it could be pleasurable for the child to stop breathing all of the time because they get a euphoric high. Or they do this because they're agitated".

However, the scientists traced the problem not to the cortex but to the breathing center itself--in the medulla. The scientists isolated the breathing center from mutant mice and were able to demonstrate that the same erratic breathing pattern, which is so characteristic for RS, also was expressed in the isolated brain tissue, revealing the breathing center as the source of the problem.........

JoAnn      Permalink


December 16, 2005

More U.S. Lives Could Be Saved By Ensuring Access To Existing Medical Treatments

More lives could be saved in the United States by spending less money on making medical therapys better and more on getting existing therapys to the patients who need them, as per a studypublished by a Virginia Commonwealth University family medicine and public health physician.

"For every dollar Congress gives the National Institutes of Health to develop blockbuster therapys, it spends only one penny to ensure that Americans actually receive them," said Steven H. Woolf, M.D., professor and director of research in VCU's Department of Family Medicine and a member of the National Academy of Sciences' Institute of Medicine. "This reflects, in part, a misperception that the improved drugs, procedures and the like will improve health outcomes, and that does happen. But the health improvement would be far greater if we worried less about making incremental improvements on existing therapys and more on the system barriers that impede Americans from receiving those therapys correctly." The study was coauthored by Robert E. Johnson, Ph.D., an associate professor in VCU's Department of Biostatistics.

Woolf and Johnson, whose study appears in the Dec. 6 issue of the Annals of Family Medicine, said a mathematical construct proves the point. They used two case studies -- one involving statins and the other antiplatelet drugs -- to show that the billions of dollars spent on new generation drugs saved fewer lives and prevented fewer strokes than if the existing drugs had been taken by all patients who could benefit. They cited reports that Americans receive only half of recommended health care services and that disparities in care are worse for minorities and disenfranchised patients.

The study poses a contrast between efficacy, or how well a therapy works, and what they call the "fidelity of health care." Independent of the efficacy, fidelity is the extent to which the health care system provides patients the precise interventions they need, delivered properly, precisely when they need them.........

Janet      Permalink


December 16, 2005

Tobacco Scenes In Movies Boost Teen Smoking

The first complete review of research on the link between teenagers viewing on-screen smoking and then taking up smoking themselves finds that one leads to the other.

The review concludes that eliminating scenes of smoking in new youth-rated films should substantially reduce smoking initiation in the adolescent years, when the vast majority of smokers start.

"The weight of dozens of studies, after controlling for all other known influences, shows the more smoking that kids see on screen, the more likely they are to smoke," said lead author Annemarie Charlesworth, a research specialist at the University of California, San Francisco Institute for Health Policy Studies. "This strong empirical evidence affects hundreds of thousands of families".

The research review, published in the recent issue of Pediatrics, a peer-reviewed publication of the American Academy of Pediatrics, examined the findings of 42 studies on how viewing on-screen smoking affects adolescent and teen smoking behavior.

Among the conclusions:

• U.S. movies again show as much smoking as they did in 1950. The balance of smoking has swung toward youth-rated (G/PG/PG-13) films.
• Films very rarely depict negative consequences of smoking. They depict smoking as "adult" and skew smoking unrealistically toward higher status characters.
• For teen audiences, anti-tobacco spots shown before movies with on-screen smoking countered much of the promotional effect of smoking in the movies.

........

Janet      Permalink


December 16, 2005

antioxidant linked to Alzheimer's and Parkinson's

A study conducted at the San Francisco VA Medical Center has identified a protein found in both mice and humans that appears to play a key role in protecting neurons from oxidative stress, a toxic process linked to neurodegenerative illnesses including Alzheimer's and Parkinson's diseases.

The study, led by Raymond Swanson, MD, chief of neurology and rehabilitation services at SFVAMC, identified the protein - known as EAAC1 in mice and as EAAT3 in humans - as the main mechanism through which the amino acid cysteine is transported into neurons. Cysteine is an essential component of glutathione, which Swanson terms "the most important antioxidant in the brain".

It had been thought previously that the main function of the protein was to remove excess glutamate, a neurotransmitter, from brain cells.

"It's known that neurons don't take up cysteine directly, and it's never been clear exactly how it gets there," says Swanson, who is also professor and vice chair of neurology at the University of California, San Francisco. "This study provides the first evidence that EAAC1 is the mechanism by which cysteine gets into neurons - and that transporting cysteine is probably its chief function".

Study findings are currently available in the Advance Online Publication section of Nature Neuroscience.

Antioxidants such as glutathione provide protection from oxidative stress, which kills cells through the "uncontrolled reaction of lipids in the cells with oxygen-basically, burning them out," says Swanson. Since the brain uses a lot of oxygen and is "chock full of lipids," it is especially vulnerable to oxidative stress, he notes.

In the first part of the study, Swanson and his co-authors observed a colony of mice deficient in the gene responsible for the production of EAAC1 and compared their behavior with that of a colony of normal, or "wild type," mice. They noticed that around the age of 11 months - old age for a mouse - the gene-deficient mice began to act listlessly, not groom themselves properly, and exhibit other signs of senility. In contrast, the wild type mice "looked and acted totally normal," according to Swanson.........

Daniel      Permalink


December 16, 2005

Screening Newborn for 'Bubble Boy Disease'

Two new UCLA studies show that newborn screening for Severe Combined Immunodeficiency (SCID) - a rare, treatable disorder of the immune system usually known as "bubble boy disease" - is both cost-effective and could be done accurately using a two-tiered testing method.

"We wanted to determine whether testing for SCID should be added to the universal screening panel for inherited disorders," said Dr. Sean McGhee, clinical instructor of pediatric immunology at Mattel Children's Hospital at UCLA. "Treatment is now advanced enough that 95 percent of children can be cured, but newborns must be detected in the first month, before the onset of severe infections".

In the first study - detailed in the November edition of the Journal of Pediatrics - UCLA scientists concluded that SCID screening could result in a large benefit to infants, making screening relatively cost-effective in spite of the low incidence of the disease. However, an adequate test would be critical to cost-effectiveness.

The analysis is the first of its kind to examine formally cost and benefits of SCID newborn screening.

To conduct the study, scientists used information about the costs of diagnosing and treating SCID and the benefits of early diagnosis, and performed a cost-benefit analysis comparing universal screening with screening only those with a family history of SCID.

Scientists determined that a SCID screening test that cost less than five dollars with a false-negative rate of 0.9 percent and a false-positive rate of 0.4 percent would be considered cost-effective by most currently accepted standards.

A nationwide screening program would cost an additional $23.9 million per year for screening costs, but would result in 760 years of life saved per year of screening.........

JoAnn      Permalink


December 16, 2005

tips to avoid "Holiday Heart Syndrome"

Thanksgiving--the official start of the holiday season, is over.

And the parties, the official way to celebrate the holidays, have begun.

Be careful, though, warns Marc Tecce, M.D., a cardiologist at Thomas Jefferson University Hospital in Philadelphia. Watch what you eat, and particularly what you drink. After all, he points out, more and more people today are living with some form of heart disease. The only caveat is to be smart--don't let having a "good time" ruin your good health.

"Prolonged alcohol consumption over the period between Thanksgiving and New Year's Day can bring on what is usually known as Holiday Heart Syndrome. This is a period where partaking in too much holiday cheer can cause cardiac rhythm abnormalities," he says.

Dr. Tecce recommends that people take special note of their holiday patterns. "Even if you are not a heavy drinker, if you go to even three parties a week--and partake of anything more than soda, juice or sparkling water, your alcohol consumption will be higher than normal," he says. "Those extra flutes of champagne or glasses of wine can affect more than just your waistline."

"You want to avoid several episodes of drinking more than what you consider to be normal for you. Never binge--which means having six or more alcoholic drinks in one afternoon or evening," warns Dr. Tecce, who is also clinical assistant professor of Medicine at Jefferson Medical College of Thomas Jefferson University.

Particularly during the holiday season, Dr. Tecce says, people should be aware of how they feel. One potential indication of a problem is when the heart beats too slow, too fast or has extra or skipped beats. This condition is known as arrhythmia.

"Arrhythmia is a serious condition that can be treated, so you should be sure to consult a clinician if your heart is beating irregularly. Better still," he suggests, "don't put yourself in a position where you have to learn about arrhythmias."........

Daniel      Permalink


December 15, 2005

New Model Of Prostate Cancer

Scientists have developed a new line of prostate cancer cells that they hope will provide a better model to study the disease.

This new cancer-cell line has already provided some help. One new study in mice identified a promising possible treatment to reduce skeletal pain that accompanies prostate cancer. Researchers found that a substance called anti-nerve growth factor appeared to be more effective in controlling pain in mice than even morphine.

But the work would not have been possible without the new cell line, said Tom Rosol , a co-author of study and a professor of veterinary medicine at Ohio State University.

Armed with this new cell line, researchers will be able to more directly study how prostate cancer affects the body, said Rosol, whose laboratory developed the cell line.

Metastatic bone tumors are a common manifestation in patients with late-stage breast cancer or prostate cancer. "Metastasis" means that cancer has spread from its original site to other areas of the body. But breast cancer typically destroys bone at tumor sites, whereas prostate cancer tumors that spread to bone induce abnormal bone growth.

Currently, most models used to study prostate cancer do not mimic the human condition and the resulting bone metastases. Most of these models really mimic the spread of breast cancer since the bone metastases in that disease are associated with bone loss rather than bone growth.

"Even though there is more bone at the sites of prostate cancer tumors, this formation still damages the bone," said Rosol, who is also dean of the College of Veterinary Medicine at Ohio State . "The new growth compresses nerves, making it terribly painful for the patient".

The results appear in a January issue of the journal Cancer Research. The study was led by Patrick Mantyh, a professor of preventive sciences at the University of Minnesota.........

Mark      Permalink


December 15, 2005

New Microchip Technology Assembles FDG

microchip device no bigger than a stamp may soon cheaply and efficiently produce FDG for human imaging. The computer-controlled "lab-on-a-chip" device, designed by graduate student Chung-Cheng Lee of the California Institute of Technology (CalTech; Pasadena) and his colleagues, can rapidly prepare doses of unstable compounds like the PET scan probe from basic chemical feedstock and F-18. The technology has the potential produce a wide variety of molecular imaging agents.

The design is the result of a collaboration between academic and industrial scientists at CalTech, the David Geffen School of Medicine at the University of California at Los Angeles (UCLA), Howard Hughes Medical Institute in Los Angeles, Stanford University School of Medicine (Stanford, CA), Siemens, and Fluidigm Corporation.

"Multistep Synthesis of a Radiolabeled Imaging Probe Using Integrated Microfluidics," by Chung-Chen Lee, et al., was published in the December 16 issue of the journal Science (2005;310:1793-1797). As a proof of principle, the group of academic and commercial researchers demonstrated that FDG could be synthesized by the stamp-size chip. These chips are similar in design to integrated electronic circuits, except that they are made of fluid channels, chambers, and valves that allow them to perform multiple chemical operations, synthesizing molecules and labeling them with radioisotopes. All the operations of the chip are controlled and executed by a standard office computer.

The chips use microfluid circuitry to integrate many chemical processes in a small space with no opportunity for cross-contamination, and it is possible to design and build circuits to synthesize new compounds in about two days, according to Hsian-Rong Tseng, PhD, coauthor and assistant professor of molecular and medical pharmacology, Crump Institute for Molecular Imaging, UCLA.........

Daniel      Permalink


December 15, 2005

Pretreating Rogue Cancer Cells With Aspirin

For years, we have heard about the health benefits of taking low doses of aspirin - preventing everything from Alzheimer's disease to heart attacks and stroke. The news about aspirin just keeps getting better. As per a research findings published in the Dec. 9 issue of the Journal of Biological Chemistry, University of Pittsburgh scientists report that aspirin, combined with a promising new cancer treatment known as tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), can induce cancer cells previously resistant to TRAIL treatment to self-destruct. The investigators say that if these findings hold up in larger studies, aspirin could become a routine treatment for helping to prevent the recurrence of a number of aggressive cancers, such as prostate and colon cancers.

"When cancers recur after initial treatment, they tend to be extremely aggressive and patient prognosis is poor," said Yong J. Lee, Ph.D., professor in the departments of surgery and pharmacology, University of Pittsburgh School of Medicine, and lead author of the study. "If we could find ways to prevent these secondary cancers from occurring, we could save a number of lives. Aspirin is a low-cost medicine that, in our studies, appears to have great potential for helping to prevent such cancer recurrences".

TRAIL is a protein that is expressed by cells of the immune system. Numerous studies have shown that TRAIL induces programmed cell death, or apoptosis, in cancer cells while having little or no effect in normal healthy cells. Apoptosis is one of several mechanisms by which damaged cells self-destruct and is the body's way of ensuring that only healthy cells reproduce. Most often, apoptosis eliminates rogue cells with damaged DNA or cells growing too quickly, but it also eliminates normal cells that have simply become obsolete as an organism grows and develops. Because cancer cells have lost their ability to undergo apoptosis, they continue to reproduce and spread their damaged progeny throughout the body.........

Daniel      Permalink


December 15, 2005, 11:22 PM CT

Prenatal Test: Detection Of Genetic Disorders

A new chromosomal test developed at Baylor College of Medicine in Houston can now alert pregnant women to an array of fetal disorders otherwise undetectable by conventional tests. This testing is discussed in a commentary and editorial in today's edition of the journal Nature.

"It's the beginning of a sea change in prenatal diagnosis," said Dr. Arthur Beaudet, chair of molecular and human genetics at BCM. "You are going to be able to detect a range of the most severe conditions, and in the future this can be cheaper than current methods hopefully using a very noninvasive approach." The new test can find more disorders and is as at least as fast as prior techniques.

The technique could even lead to more general use of prenatal screening for these disorders, said Beaudet.

The new test uses a gene chip or microarray to analyze various areas of the human genome for abnormal regions that contain too a number of or too few copies of the genetic material. These gains or losses in DNA can lead to devastating genetic conditions that present serious disabilities for the lives of children born with them.

The microarray or gene chip is like a map that is covered with tiny dots consisting of DNA from known locations on each of the 46 chromosomes. DNA from the patient is labeled one color (for example, red), and DNA from a normal person (control) is labeled another color (in this example, green). The two DNAs are then mixed and added to the microarray. The appropriate part of the genome seeks out the appropriate dot of DNA on the chip and attaches to it. If the DNA in both patient and control is normal, then the two colors of the dye even out and that dot turns yellow. If there is too much DNA (as happens when there are three instead of two copies of a region or an entire chromosome), the dot is more red because there is more of the patient's DNA. If there is too little, the dot is greener because there is more of the control's DNA and less of the patient's.........

Emily      Permalink


December 15, 2005, 11:17 PM CT

"Hospital at Home" Offers Quality Care

Being hospitalized can be a traumatic experience, particularly for older persons. Hospitals are noisy, disorienting, full of strangers and infections often spread among patients.

Now a new study has shown that for older persons with certain acute conditions, hospital-level care can be provided at home for less money and with fewer clinical complications than in-hospital care.

In addition, patients recovered sooner when "hospitalized" at home, the study found, and they and their families were more satisfied with the whole experience.

The program, called Hospital at Home, was carried out by the University at Buffalo, Yale University and Oregon Health and Science University. Bruce Leff, M.D., from The Johns Hopkins University, oversaw the project.

Results of the program appear in the current issue (Dec. 6) of Annals of Internal Medicine.

The program in Buffalo was a collaboration among four institutions -- UB, Kaleida Health, Independent Health and Univera.

"The success of our collaboration provides a model for establishing home hospital programs within communities with multiple competing health-care organizations," said Bruce Naughton, M.D., principal investigator on the Buffalo project and director of the UB Division of Geriatrics.

"Work is continuing in Buffalo with the goal of establishing a sustainable home hospital program," added Naughton, associate professor of medicine at UB.

The program was carried out in two consecutive 11-month phases. All patient participants came to a hospital suffering from one of four target illnesses: community-acquired pneumonia, exacerbation of chronic heart failure, exacerbation of chronic obstructive pulmonary disease or cellulitis.........

Janet      Permalink


December 15, 2005

Prepregnancy Weight Increasing

A growing number of women are overweight or obese when they become pregnant, a condition that is risky to both mother and baby, a new study conducted by scientists at the University at Buffalo has shown.

An analysis of the prepregnancy body mass index of more than 79,000 women in eight counties of Western New York who became pregnant between 1999 and 2003 found that the number of women who were overweight when they became pregnant increased by 11 percent and the number who were obese increased by 8 percent over that time period.

There was a corresponding decrease in the percentage of women who were normal weight or underweight in the prepregnancy period over those five years, results showed. The shift applied regardless of age, ethnicity (black or white), education level, type of insurance, prior live births, urbanization status, median family income and smoking status.

The study appears in the current (Dec. 2005) issue of the American Journal of Obstetrics and Gynecology.

The results are thought to apply to the population-at-large because they are consistent with findings in at least three prior papers and because of the large sample size.

"Cumulatively, 40.5 percent of all patients had prepregnancy BMIs in the overweight and obese categories in 2003 compared with 37.1 percent in 1999," said John Yeh, M.D., lead author who is professor and chair of the Department of Gynecology-Obstetrics, UB School of Medicine and Biomedical Sciences. "This represents a relative 9.2 percent increase over five years of the study.

"This increase in obesity is important to the obstetrician and the patient because obesity can be a high-risk situation in a pregnant woman," said Yeh. "Obese patients who become pregnant are at increased risk of developing gestational diabetes, pregnancy-related hypertension, preeclampsia, neonatal death and labor complications".........

Emily      Permalink


December 15, 2005

Cerebral Cortex Suggested As Genesis Of Tremors

Parkinson's disease, first described nearly 200 years ago by a British clinician for whom the disease is named (and who dubbed it the "shaking palsy"), is widely thought to show abnormalities in the basal parts of the brain - causing the characteristic tremors, stiffness of the limbs and poor balance.

Now new research led by John Caviness, M.D., Professor of Neurology at Mayo Clinic in Arizona, suggests that the cerebral cortex of the brain is also responsible for significant abnormal muscle activity in Parkinson's disease. The study results were published in the October 2005 edition of Movement Disorders Journal.

Typically parkinson's disease, part of a group of conditions known as motor system disorders, is characterized by tremor of the hands and arms, as well as stiffness of the limbs and slowness of movement.

Nearly 50,000 Americans generally over age 50 are affected by the progressive disease each year, and medical science has struggled to pinpoint exact causes in the vast majority of cases.

The basal portion of the human brain is thought to regulate movement in a place called basal ganglia. It has long been thought that the abnormal basal ganglia in Parkinson's disease patients produce the movement problems. The cerebral cortex, the outermost layer of the brain considered the most complex portion, is also involved in voluntary movement execution and regulates planning, problem-solving, language and speech.

In the study, Dr. Caviness - along with authors from Barrows Neurological Institute, Phoenix, and Sun Health Research Institute, Sun City, Ariz., - examined the significance of postural tremors in patients with Parkinson's. Postural tremor, as opposed to "rest" tremor in Parkinson's, is observed when a patient attempts to "hold" or "posture" against gravity - such as holding one's arms out in front.........

Daniel      Permalink


December 15, 2005

Can most types of cancers be prevented?

It's a question that has emerged in the past 20 years, given advances in screening and early diagnosis, rapid developments in genetics and molecular biology, and progress in the therapy of early disease and in next-generation targeted therapies.

And finding answers is one of the top goals of The University of Texas M. D. Anderson Cancer Center, which has one of the largest cancer prevention research programs in the world.

M. D. Anderson was among the first to begin dedicated prevention research efforts in the late 1970s. A decade ago, nine faculty were working on 23 projects -- a pursuit that was regarded as trend-setting at the time. The cancer center's focus on prevention has grown so much in recent years that the 48 faculty, involved in 140-plus research projects and clinical programs valued at more than $20 million in 2005 alone, just moved into the new Cancer Prevention Building.

In addition to housing faculty offices, the building's Cancer Prevention Center and new Behavioral Research and Treatment Center provide advanced early detection and risk-reduction services and state-of-the-art biobehavioral and psychosocial research venues.

These two centers involve only a sliver of the basic and applied research under way. In short, the researchers, physicians, nurses, employees and volunteers that staff this building aim to bring about a future that may some day be free of cancer.

They also are the first to say that attaining this goal will not be easy; that prevention will require developing a wide variety of strategies and associated tactics to curtail the variety of different diseases, all called cancer, that have now emerged as the number one killer of Americans under age 85.

"Prevention is very broad," says Bernard Levin, M.D., vice president and head of the Division of Cancer Prevention and Population Sciences. "It is not just prevention of cancer development, but includes advances in diagnosis and therapy that reduce suffering and mortality from the disease".........

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