April 13, 2008, 9:08 PM CT
Disparities in depression
Older Puerto Ricans have higher rates of depression than other Hispanics living in the United States, as per a new study by scientists at Hebrew SeniorLifes Institute for Aging Research (IFAR).
Nearly 7 percent of Puerto Ricans, who make up 11 percent of the Hispanics 65 and older in the U.S., suffer from major depression, in comparison to Mexican Americans, Cuban Americans, and Hispanics from Central and South America. Only 2.8 percent of Mexican Americans (46.7 percent of the older Hispanic population) and 2.5 percent of Cuban Americans (13 percent) suffer from major depression.
We found the prevalence of depression across Hispanic groups in the United States to be highest in Puerto Ricans, even though this was the smallest group, the scientists wrote in the Journal of Gerontology: Psychological Sciences.
Funded in part by the National Institute on Aging, the study was conducted by IFAR researchers Frances M. Yang, Ph.D., and Richard N. Jones, Sc.D., along with Yamileth Cazorla-Lancaster of the University of North Texas School of Public Health.
The scientists examined differences in the levels of depressive symptoms and the presence of depression in 759 Hispanics over the age of 59. Data was obtained from the University of Michigans Health and Retirement Study and its Asset of Health Dynamics of the Oldest Old (AHEAD) study.........
Posted by: JoAnn Read more Source
April 13, 2008, 9:05 PM CT
Autism and muscle weakness
Some kids with autism may have a genetic defect that affects the muscles, according to research that will be presented at the American Academy of Neurology 60th Anniversary Annual Meeting in Chicago, April 1219, 2008.
The study looked at 37 children with autism spectrum disorders who were evaluated for mitochondrial disease,.
which causes muscle weakness and prevents a child from being able to participate in physical activities and.
sports. Mitochondrial disease occurs when genetic mutations affect the mitochondria, or the part of the cell that releases energy.
A total of 24 of the children, or 65 percent, had defects in the process by which cells produce and synthesize energy in the muscles, or oxidative phosphorylation defects in the skeletal muscles.
Most children with autism spectrum disorders do not have recognizable abnormalities when you look at.
genetic tests, imaging, and metabolic tests, said study author John Shoffner, MD, owner of Medical.
Neurogenetics, LLC in Atlanta, GA, and member of the American Academy of Neurology. But a subset of these children does have significant defects in this area. Identifying this defect is important for understanding how genes that produce autism spectrum disorders impact the function of the mitochondria.........
Posted by: JoAnn Read more Source
April 13, 2008, 8:56 PM CT
Exercise may lead to faster prostate tumor growth
Prostate tumors grew more quickly in mice who exercised than in those who did not, leading to speculation that exercise may increase blood flow to tumors, as per a new study by scientists in the Duke Comprehensive Cancer Center (DCCC) and the Duke Prostate Center.
Our study showed that exercise led to significantly greater tumor growth than a more sedentary lifestyle did, in this mouse model, said Lee Jones, Ph.D., a researcher in the DCCC and senior investigator on this study. Our thought is that we may, in the future, be able to use this finding to design better drug delivery models to more effectively treat patients with prostate cancer, and those with other types of cancer as well.
The findings were presented in a poster session at the American Association for Cancer Research annual meeting on April 13 in San Diego, Calif. The study was funded by the United States Department of Defense, the Prostate Cancer Foundation and the American Urological Association Foundation, Rising Star in Urology Award, given to Stephen Freedland, one of the studys investigators.
The scientists implanted prostate tumors subcutaneously in the flanks of 50 mice and then put half of the mice in cages with exercise wheels and half in cages with no wheels. All mice were fed the same diet. On average, the exercising mice ran more than half a mile each day.........
Posted by: Mark Read more Source
April 13, 2008, 8:54 PM CT
Smoking related to subset of colorectal cancers
Smoking puts older women at significant risk for loss of DNA repair proteins that are critical for defending against development of some colorectal cancers, as per research from a team led by Mayo Clinic scientists.
In a study being presented at the annual meeting of the American Association for Cancer Research (AACR), the scientists observed that women who smoked were at increased risk for developing colorectal tumors that lacked some or all of four proteins, known as DNA mismatch repair (MMR) proteins. These proteins keep cells lining the colon and rectum healthy because they recognize and repair genetic damage as well as mistakes that occur during cell division.
Scientists think that, in this study population, few if any of the four proteins were absent because of an inherited genetic alteration. We believe that smoking induces a condition within intestinal cells that does not allow MMR genes to express their associated proteins, and this loss leads to formation of tumors in some women, says the studys lead author, Mayo gastroenterologist Paul Limburg, M.D.
The scientists also discovered a direct association between the number of cigarettes smoked daily by study participants and increased risk of developing these specific tumors. They say a number of prior studies have observed only a very weak positive association between use of cigarettes and development of the cancer.........
Posted by: Sue Read more Source
April 13, 2008, 8:48 PM CT
A genetic cause for iron deficiency
The discovery of a gene for a rare form of inherited iron deficiency may provide clues to iron deficiency in the general population especially iron deficiency that doesnt respond to iron supplements - and suggests a new therapy approach. The finding was published online by the journal Nature Genetics on April 13.
Iron deficiency is the most common nutritional deficiency and the leading cause of anemia in the United States.(1) Most cases are easily reversed with oral iron supplements, but over the years, Mark Fleming, MD, DPhil, interim Pathologist-in-Chief at Childrens Hospital Boston, and pediatric hematologist Nancy Andrews, MD, PhD, formerly of Childrens and now Dean of Duke University School of Medicine, had been referred many children with iron deficiency anemia who didnt respond to oral supplements, and only poorly to intravenous iron.
The cause of their condition termed iron-refractory iron-deficiency anemia (IRIDA) was a mystery. The children all had good diets, and none had any condition that might interfere with iron absorption or cause chronic blood loss, the most common causes of iron deficiency. All had evidence of anemia from a very early age, and a number of also had siblings with iron deficiency anemia. Seeing reports of several similarly afflicted families in the medical literature, Fleming and Andrews were convinced that genetics was a factor.........
Posted by: Scott Read more Source
April 13, 2008, 8:44 PM CT
Mouth may tell the tale of lung damage
Li Mao, M.D., professor in M. D. Anderson's Department of Thoracic/Head and Neck Medical Oncology.
Cells lining the mouth reflect the molecular damage that smoking does to the lining of the lungs, scientists at The University of Texas M. D. Anderson Cancer Center report today at the annual meeting of the American Association for Cancer Research.
Examining oral tissue lining the mouth to gauge cancer-inducing molecular alterations in the lungs could spare patients and those at risk of lung cancer from more invasive, uncomfortable procedures used now, said senior researcher Li Mao, M.D., professor in M. D. Anderson's Department of Thoracic/Head and Neck Medical Oncology.
"We are talking about just a brushing inside of the cheek to get the same information we would from lung brushings obtained through bronchoscopy," said study presenter and first author Manisha Bhutani, M.D., a post-doctoral fellow in Thoracic/Head and Neck Medical Oncology.
The team examined the oral and lung lining tissue - called the epithelium - in 125 chronic smokers enrolled in a large, prospective lung cancer chemoprevention study.
The status of two crucial tumor-suppressing genes was analyzed. The genes, p16 and FHIT, are known to be damaged or silenced very early in the process of cancer development. "There is substantial damage long before there is cancer," Mao said.........
Posted by: Scott Read more Source
April 13, 2008, 8:43 PM CT
Connection between protein and prognosis in breast cancer
Oregon Health & Science University Cancer Institute scientists have observed that a tumor protein present in an aggressive form of breast cancer is correlation to a poor prognosis.
The presence of the protein, called growth factor receptor-bound protein-7, often referred to as GRB-7, in breast cancer tumors, is strongly correlation to the growth and spread of the cancer, as per principal investigator Shiuh-Wen Luoh, M.D., Ph.D., assistant professor of medicine (hematology/medical oncology) in the OHSU School of Medicine.
The research will be presented Sunday, April 13, at 1 p.m. at the annual American Association for Cancer Research meeting in San Diego.
The GRB-7 protein previously has been shown to be important to cell communication in the spread of cancer. The GRB-7 gene is located close to the HER-2/Neu gene that regulates breast cancer growth. The OHSU Cancer Institute scientists discovered that the levels of GRB-7 protein are often heightened at the same time that HER-2/Neu levels are high. Also, not infrequently, they found breast tumors that overexpressed one but not the other protein. Overexpression means that there is an abundant presence of the protein.
It is surprising that we found discordance in the overexpression of these genes because they are so close together, Luoh said.........
Posted by: Janet Read more Source
April 13, 2008, 8:41 PM CT
Targeted therapy combination for liver cancer
Scientists at the University of Pennsylvania School of Medicine and Abramson Cancer Center reported today at the annual meeting of the American Association for Cancer Research that combining two targeted therapies overcomes therapy resistance in liver cancer cell lines. The team is currently designing a trial to test the combination in patients.
Liver cancer is resistant to a number of chemotherapies and to cell-death inducing agents. Last year, however, the U.S. Food and Drug Administration approved sorafenib (Nexavar) as a therapy for liver cancer after a clinical trial showed that the targeted agent prolonged survival in some patients.
Unfortunately not all patients respond to sorafenib and the drug does not cure the disease.
Therefore, Wafik El-Deiry, MD, PhD, Professor of Medicine, Genetics, and Pharmacology, and co-Program Leader of Radiation Biology in the Abramson Cancer Center, and his colleagues have tested other targeted agents in combination with sorafenib.
They observed that treating liver cancer cells with sorafenib and an antibody or the natural ligand that stimulates programmed cell death via the TRAIL pathway, dramatically increases the rate of cell death.
Sorafenib by itself causes a little cell death, but not that much, Dr. El-Deiry said. Now you combine sorafenib and TRAIL, and all of the sudden you get massive cell death. It is a real synergistic interaction. It is very profound killing.........
Posted by: Janet Read more Source
April 10, 2008, 9:23 PM CT
Wine may protect against dementia
There may be constituents in wine that protect against dementia. This is shown in research from the Sahlgrenska Academy at University of Gothenburg in Sweden.
The findings are based on 1,458 women who were included in the so-called Population Study of Women from 1968. When they were examined by physicians they were asked to report how often they drank wine, beer, and liquor by selecting from seven categories on a scale from never to daily. The scientists know nothing about how much they drank on each occasion, or how correct the estimates were. For each beverage the women reported having drunk more than once a month, they were classified as a consumer of that particular beverage.
Thirty-four years after the first study, 162 women had been diagnosed with dementia. The results show that among those women who reported that they drank wine a considerably lower proportion suffered from dementia, whereas this correlation was not found among those who had reported that they regularly drank beer or liquor.
The group that had the lowest proportion of dementia were those who had reported that the only alcohol they drank was wine, says Professor Lauren Lissner, who directs the study in collaboration with Professor Ingmar Skoog, both with the Sahgrenska Academy.........
Posted by: Daniel Read more Source
April 10, 2008, 9:17 PM CT
Developing targeted chemotherapy
Scientists from the University of Pennsylvania School of Medicine and his colleagues discovered that the Notch signaling pathway, which determines the development of a number of cell types, and is also implicated in some cancers, is not universally essential for the maintenance of stem cells. The findings appear this week in Cell Stem Cell, and indicate that inhibitors of Notch may not affect bone marrow stem cells.
Notch is one of a select set of proteins that influence the development of a wide variety of types of cells. Previous work has shown that increases in signals generated by Notch are important in certain human tumors, especially some kinds of childhood leukemia, making Notch an attractive target for new cancer therapies. However, it has also been suggested that Notch is needed to maintain the stem cells in the bone marrow from which normal blood cells are formed, raising the concern that Notch inhibitors might destroy the normal bone marrow. This potential risk raised important questions about treating leukemia patients with Notch inhibitors, notes senior author Warren Pear, MD, PhD, Associate Professor of Pathology and Laboratory Medicine and the Abramson Family Cancer Research Institute.
Prior work from the Pear lab and others has shown that Notch signals are mandatory for the proper development of lymphocytes. More importantly in terms of human disease, work done together with co-author Jon Asters lab at Harvard over the last decade has shown that abnormal increases in Notch signaling cause T-cell acute lymphoblastic leukemias, which make up about 15-20 percent of childhood leukemias. Growth of these leukemias can be stopped in the laboratory by new kinds of Notch pathway inhibitors.........
Posted by: Janet Read more Source