January 16, 2011, 8:46 PM CT
Neurons of the deep brain
This is a diagram of the experimental setup. (left) Tiny optical instruments called microendoscopes are inserted into glass imaging guide tubes, which maintain a precise position in the brain. This allows researchers to view the exact same neuron with a microscope (right) again and again, a new technique for brain researchers. Scientists can also compare diseased tissue, such as a tumor, to healthy tissue in the same animal.
Credit: Modified image courtesy Mark Schnitzer and Nature Medicine.
Travel just one millimeter inside the brain and you'll be stepping into the dark.
Standard light microscopes don't allow scientists to look into the interior of the living brain, where memories are formed and diseases such as dementia and cancer can take their toll.
But Stanford researchers have devised a new method that not only lets them peer deep inside the brain to examine its neurons but also allows them to continue monitoring for months.
The technique promises to improve understanding of both the normal biology and diseased states of this hidden tissue.
Other recent advances in micro-optics had enabled researchers to take a peek at cells of the deep brain, but their observations captured only a momentary snapshot of the microscopic changes that occur over months and years with aging and illness.
The Stanford development appears online Jan. 16 in the journal Nature Medicine
It also will appear in the February 2011 print edition.
Researchers study a number of diseases of the deep brain using mouse models, mice that have been bred or genetically engineered to have diseases similar to human afflictions.
"Scientists will now be able to study mouse models in these deep areas in a way that wasn't available before," said senior author Mark Schnitzer, associate professor of biology and of applied physics.........
Posted by: Daniel Read more Source
January 16, 2011, 8:37 PM CT
MicroRNA suppresses prostate cancer stem cells
Dean Tang, Ph.D. is a researcher at the University of Texas MD Anderson Cancer Center.
Credit: The University of Texas MD Anderson Cancer Center
A small slice of RNA inhibits prostate cancer metastasis by suppressing a surface protein usually found on prostate cancer stem cells. A research team led by researchers at The University of Texas MD Anderson Cancer Center reported today in an advance online publication at Nature Medicine
"Our findings are the first to profile a microRNA expression pattern in prostate cancer stem cells and also establish a strong rationale for developing the microRNA miR-34a as a new therapy option for prostate cancer," said senior author Dean Tang, Ph.D., professor in MD Anderson's Department of Molecular Carcinogenesis.
MicroRNAs, or miRNAs, are short, single-stranded bits of RNA that regulate the messenger RNA expressed by genes to create a protein.
Cancer stem cells are capable of self-renewal, have enhanced tumor-initiating ability and are generally more resistant to therapy than other cancer cells. They are linked to tumor recurrence and metastasis, the lethal spreading of cancer to other organs. These capacities are more prevalent in cancer cells that feature a specific cell surface protein called CD44, Tang said.
"CD44 has long been associated with promotion of tumor development and, especially, to cancer metastasis," Tang said. "A number of cancer stem cells overexpress this surface adhesion molecule. Another significant finding from our study is identifying CD44 itself as a direct and functional target of miR-34a".........
Posted by: Mark Read more Source
January 12, 2011, 6:41 PM CT
Robotic surgery of 'tremendous benefit' to patients
Robot-assisted surgery dramatically improves outcomes in patients with uterine, endometrial, and cervical cancer, said scientists at the Jewish General Hospital's Lady Davis Institute for Medical Research in Montreal. Moreover, because of fewer post-operative complications and shorter hospital stays, robotic procedures also cost less.
These results were published in late 2010 in a series of studies in The Journal of Robotic Surgery
and The International Journal of Gynecological Cancer
To date, adoption of robotic surgery has been slowed by fears that it will raise overall healthcare costs. In Canada, robotic procedures are still not covered by any provincial healthcare plan.
"To the contrary, robotic surgery definitely benefits patients and society," said Dr. Walter H. Gotlieb, Head of Gynecologic Oncology at the JGH Segal Cancer Centre. "Patient quality of life is dramatically improved, their hospital stays are much shorter and they use far less narcotic pain medication. The majority of our patients need nothing stronger than Tylenol".
In a robot-assisted operating room, the doctor sits at a computer console and manipulates multiple robot arms, rather than working directly on the patient. The technology was developed to overcome the limitations of minimally invasive surgery (MIS), including such notoriously difficult procedures as laparoscopy for cancer.........
Posted by: Scott Read more Source
January 11, 2011, 6:49 AM CT
Powerful biomarker panel for the early detection of breast cancer
In the war on cancer, perhaps there is nothing more powerful in a physician's arsenal than early detection. Despite recent advances in early detection and therapy, breast cancer remains a common and significant health problem in the United States and worldwide. Approximately one in ten women will get breast cancer in their lifetime and more than half of women with late stage cancer (II and III) have no cure or effective therapeutic available.
Using a new, powerful method for rapidly screening molecules linked to disease, proteomics expert Joshua LaBaer and his colleagues from the Biodesign Institute at Arizona State University have identified a broad panel of 28 early predictors, or biomarkers, that may one day aid in the early diagnosis of breast cancer.
"We do not have any available blood markers for breast cancer," said LaBaer, a Virginia G. Piper Chair in Personalized Medicine at ASU who directs the Center for Personalized Diagnostics at the Biodesign Institute. "Our hope is to combine a new type of blood test with mammography screening to aid in the early detection of breast cancer".
The findings represent the first demonstration of a custom protein array technology deployed to find biomarkers in patients with breast cancer before they were clinically diagnosed for cancer. These biomarkers were specific for patients with breast cancer and not in healthy women or women with a non-malignant form of breast disease.........
Posted by: Janet Read more Source
January 11, 2011, 6:24 AM CT
Does it hurt?
It is well known that pain is a highly subjective experience. We each have a pain threshold, but this can vary depending on distractions and mood. A paper in the International Journal of Behavioural and Healthcare Research
offers a cautionary note on measuring perceived pain in research.
There are a number of chronic illnesses and injuries that have no well-defined symptoms other than pain, but because of the subjectivity in a patient's reporting of their experience of the illness or injury, healthcare workers have difficulty in addressing the patient's needs. Moreover, when subjective reporting of pain is a critical component of a clinical trial, scientists involved in the trial often find it difficult to determine efficacy from patient to patient based on the subject's own assessment of painful symptoms. Commonly, patients are asked to rate their pain on a zero to ten scale, where zero represents no pain whatsoever and a value of ten indicates excruciating pain. Unfortunately, one person's "8" appears to be another's "10" on the same scale.
When seeking to assess the effectiveness of an intervention it is common practice that patients whose post-treatment pain scores are lower than their pre-treatment scores are categorized as having undergone effective therapy. This all but ignores the subjectivity of their experience of pain, where the simple act of being "treated" may lower their perception of their pain without the underlying cause of the pain having been physically reduced.........
Posted by: JoAnn Read more Source
January 11, 2011, 6:17 AM CT
Identifying depressed students
One out of every four or five students who visits a university health center for a routine cold or sore throat turns out to be depressed, but most centers miss the opportunity to identify these students because they don't screen for depression, as per new Northwestern Medicine research.
About 2 to 3 percent of these depressed students have had suicidal thoughts or are considering suicide, the study found.
"Depression screening is easy to do, we know it works, and it can save lives," said Michael Fleming, professor of family and community medicine at Northwestern University Feinberg School of Medicine. "It should be done for every student who walks into a health center".
The consequences of not finding and treating these students can be can be serious and even deadly. "These kids might drop out of school because they are so sad or hurt or kill themselves by drinking too much or taking drugs," Fleming said.
"Things continually happen to students � a low grade or problems with a boyfriend or girlfriend -- that can trigger depression," Fleming said. "If you don't take the opportunity to screen at every visit, you are going to miss these kids."
Fleming, who joined Feinberg in the fall of 2010, is main author of a paper on the findings in the recent issue of the American Journal of Orthopsychiatry
He conducted the research when he was a faculty member at the University of Wisconsin.........
Posted by: JoAnn Read more Source
January 10, 2011, 10:19 PM CT
Abstinence, heavy drinking, binge drinking
Prior research regarding the association between alcohol consumption and dementia or cognitive impairment in later life suggests that mild to moderate alcohol consumption might be protective of dementia. However, most of the research has been conducted on subjects already rather elderly at the start of the follow-up. A newly released study reported in the recent issue of the Journal of Alzheimer's Disease
addresses this problem with a follow-up of more than two decades.
The study, conducted at the University of Turku, University of Helsinki and National Institute for Health and Welfare in Finland based on subjects from the Finnish Twin Cohort, shows that midlife alcohol consumption is correlation to the risk of dementia assessed some 20 years later. The study indicates that both abstainers and subjects consuming large amounts of alcohol have a greater risk for cognitive impairment than light drinkers.
"Our finding is significant as the changes typical of Alzheimer's disease � the most common dementia syndrome � are thought to start appearing two to three decades before clinical manifestation and therefore identification of early risk factors is imperative", states Jyri Virta, researcher at University of Turku, Finland.
In addition to total alcohol consumption, the authors were able to assess the effects of different drinking patterns. The study suggests that drinking large amounts of alcohol (defined as a bottle of wine or the equivalent) at a single occasion at least monthly is an independent risk factor for cognitive impairment. Such binge drinking doubles the risk of cognitive impairment even when total alcohol consumption was statistically controlled for.........
Posted by: Janet Read more Source
January 10, 2011, 10:17 PM CT
Nuclear receptors against cancer, obesity
Dr. Jan-Åke Gustafsson recently published two articles in a pair of high-impact journals on research with significant implications in the treatment and intervention of cancer and obesity.
Credit: Thomas Campbell
Research with significant implications in the therapy and intervention of cancer and obesity has been published recently in two prestigious journals by University of Houston (UH) biochemist Dr. Jan-�ke Gustafsson.
In an invited review in the Journal of Biological Chemistry
, the most-cited biomedical research journal in the world, Gustafsson and his team summarize the most recent results pertaining to the function of a nuclear receptor called estrogen receptor beta, or ERbeta, the biological and medical importance of which Gustafsson and his associates discovered in 1995. In the article, titled "Estrogen Signaling via Estrogen Receptor Beta," the group observed that this regulatory molecule prevents what is called epithelial-to-mesenchymal transition, or EMT, in the prostate gland. EMT is believed to have an essential role in prostate tumor development. ERbeta also has a growth-suppressive effect in colon cancer cells.
All of this, added to new insights gained by the scientists regarding ERbeta's interaction with certain genetic materials, suggests that this molecule is potentially an interesting pharmaceutical target in a number of diseases, including cancer.
A second article by Gustafsson and his group appeared in a recent issue of the journal Proceedings of the National Academy of Sciences
, one of the world's most-cited multidisciplinary scientific serials. Titled "Both liver-X receptor (LXR) isoforms control energy expenditure by regulating Brown Adipose Tissue activity," the research shows that two specific nuclear receptors � LXRalfa and LXRbeta � act in such a way as to indicate they have a crucial role in regulating energy homeostasis, which is important to maintain the stability of normal biological states during adjustments to environmental changes. Gustafsson suggests, then, that these molecules should be considered as targets in pharmaceutical intervention against obesity.........
Posted by: Scott Read more Source
January 10, 2011, 6:52 AM CT
Many survivors of the WTC attacks experience PTSD
Nearly 10 years after the greatest human-made disaster in U.S. history-- the destruction of the World Trade Center (WTC) towers -- there has been little research documenting the attacks' consequences among those most directly affected -- the survivors who escaped the World Trade Center towers. In a study just released by Columbia University's Mailman School of Public Health, in conjunction with the New York City Department of Health and Mental Hygiene and the federal Agency for Toxic Substances Disease Registry (ATSDR), scientists observed that of the 3,271 civilians who evacuated the Twin Towers, 95.6% of survivors reported at least one current posttraumatic stress symptom and 15% screened positive for Posttraumatic Stress Disorder (PTSD), two to three years after the disaster. While past studies have examined PTSD prevalence among rescue and recovery workers, Lower Manhattan residents, other downtown building occupants, and passersby, this is the first study to focus specifically on people who were inside the towers when they were struck. The full study findings are currently online in the American Journal of Epidemiology
PTSD is a psychiatric disorder that occurs after experiencing or witnessing events that threaten death or serious injury and that involves intense feelings of fear, helplessness, or horror and is the third most common anxiety disorder in the United States. The scientists report that five characteristics of direct exposure to the terrorist attacks were predictors of PTSD: a key driver was initiating evacuation late. Other predictors were being on a high floor in the towers, being caught in the dust cloud that resulted from the tower collapses, personally witnessing horror, and sustaining an injury. Working for an employer that sustained fatalities also increased risk. Each addition of an experience of a direct exposure resulted in a two hundred percent increase in the risk of PTSD.........
Posted by: JoAnn Read more Source
January 10, 2011, 6:49 AM CT
Grape ingredient resveratrol
Resveratrol, a compound in grapes, displays antioxidant and other positive properties. As per a research findings published this week, scientists at the UT Health Science Center San Antonio describe a novel way in which resveratrol exerts these beneficial health effects.
Resveratrol stimulates the expression of adiponectin, a hormone derived from cells that manufacture and store fat, the team found. Adiponectin has a wide range of beneficial effects on obesity-related medical complications, said senior author Feng Liu, Ph.D., professor of pharmacology and member of the Barshop Institute of Longevity and Aging Studies at the Health Science Center.
Both adiponectin and resveratrol display anti-obesity, anti-insulin resistance and anti-aging properties.
"Results from these studies should be of interest to those who are obese, diabetic and growing older," Dr. Liu said. "The findings should also provide important information on the development of novel therapeutic drugs for the therapy of these diseases".
The scientists confirmed the finding in cells and animal models. The study is in the Jan. 7 issue of the Journal of Biological Chemistry.Prior studies
In July 2009 in the journal Nature, the Barshop Institute and collaborators reported that the compound rapamycin extended life in mice. Rapamycin, like resveratrol, is under scrutiny for its beneficial health.........
Posted by: Scott Read more Source