Health and Medical News and Resources

General interest items edited by Janice Flahiff

Neurobiologists find that weak electrical fields in the brain help neurons fire together

Neurobiologists find that weak electrical fields in the brain help neurons fire together
Coordinated behavior occurs whether or not neurons are actually connected via synapses

From a February 2, 2011 Eureka News Alert

Ephaptic coupling leads to coordinated spiking of nearby neurons, as measured using a 12-pipette electrophysiology setup developed in the laboratory of coauthor Henry Markram.

 

Pasadena, Calif.—The brain—awake and sleeping—is awash in electrical activity, and not just from the individual pings of single neurons communicating with each other. In fact, the brain is enveloped in countless overlapping electric fields, generated by the neural circuits of scores of communicating neurons. The fields were once thought to be an “epiphenomenon, a ‘bug’ of sorts, occurring during neural communication,” says neuroscientist Costas Anastassiou, a postdoctoral scholar in biology at the California Institute of Technology (Caltech).

New work by Anastassiou and his colleagues, however, suggests that the fields do much more—and that they may, in fact, represent an additional form of neural communication.

“In other words,” says Anastassiou, the lead author of a paper about the work appearing in the journal Nature Neuroscience,** “while active neurons give rise to extracellular fields, the same fields feed back to the neurons and alter their behavior,” even though the neurons are not physically connected—a phenomenon known as ephaptic coupling. “So far, neural communication has been thought to occur at localized machines, termed synapses. Our work suggests an additional means of neural communication through the extracellular space independent of synapses.”

Extracellular electric fields exist throughout the living brain, though they are particularly strong and robustly repetitive in specific brain regions such as the hippocampus, which is involved in memory formation, and the neocortex, the area where long-term memories are held. “The perpetual fluctuations of these extracellular fields are the hallmark of the living and behaving brain in all organisms, and their absence is a strong indicator of a deeply comatose, or even dead, brain,” Anastassiou explains……

…..

What does that mean for brain computation? “Neuroscientists have long speculated about this,” Anastassiou says. “Increased spike-field coherency may substantially enhance the amount of information transmitted between neurons as well as increase its reliability. Moreover, it has been long known that brain activity patterns related to memory and navigation give rise to a robust LFP and enhanced spike-field coherency. We believe ephaptic coupling does not have one major effect, but instead contributes on many levels during intense brain processing.”

Can external electric fields have similar effects on the brain? “This is an interesting question,” Anastassiou says. “Indeed, physics dictates that any external field will impact the neural membrane. Importantly, though, the effect of externally imposed fields will also depend on the brain state. One could think of the brain as a distributed computer—not all brain areas show the same level of activation at all times……

 

**For suggestions on how to get this article for free or at low cost, click here

 

February 3, 2011 Posted by | Medical and Health Research News | , , , , , | Leave a comment

Researchers lead search for better drug-addiction treatments

Researchers lead search for better drug-addiction treatments

From a February 2, 2011 Eureka news alert

DALLAS – Feb. 3, 2011 – UT Southwestern Medical Center psychiatry researchers(Division of Addictions)are leading the Texas arm of a national network that conducts clinical trials aimed at finding effective treatments for drug addiction.

More than 100 community treatment providers and academic medical centers throughout the country are funded in part through the National Institute on Drug Abuse’s Clinical Trials Network (CTN). The Texas component includes partnerships between academic and community treatment providers in Dallas, El Paso, Austin and Houston. It is led by Dr. Madhukar Trivedi, professor of psychiatry at UT Southwestern.

“The effects of drugs on the brain are very clear, but we still need long-term answers that cure people who abuse drugs and prevent them from relapse,” Dr. Trivedi said. “I applaud NIDA for funding the infrastructure at academic institutions to research therapies in real-world treatment centers that will lead to ready-to-launch cures. Drug abuse affects not just the person, but families and society as a whole.”

Each CTN study is conducted in multiple community treatment provider sites across the country, led by a CTN substance abuse researcher and supported by the researchers in the CTN academic institutions affiliated with each participating site.

“It is critical to find new treatments in the substance abuse field where current treatments result in only modest improvements. Finding effective interventions really requires larger, multicenter treatment trials like those occurring in the CTN,” Dr. Trivedi said.

One such national study within the CTN is the Stimulant Reduction Intervention Using Dose Exercise (STRIDE)**, led by Dr. Trivedi. It is a groundbreaking study that tests the short and longer term effectiveness of adding either exercise or health education to treatment as usual in adults who abuse stimulants such as cocaine or methamphetamine. Sites participating in this study in Texas include Nexus Recovery Center and Memorial Hermann Prevention and Recovery Center as well as multiple other sites across the country.

Other studies being conducted in the CTN in Texas include a trial that tests whether an interactive web-based therapy added to usual treatment improves abstinence from drug use, and a trial that examines whether medication, counseling, and incentives to quit smoking added to usual treatment improve abstinence from drug use.

Dr. Trivedi recently received a renewal of the National Institute on Drug Abuse‘s grant to continue contributions to improve the treatment of addiction for several additional years and said he expects to receive nearly $4 million over the next year.

A national CTN goal for the next few years is to engage other types of medical doctors and treatment settings who treat people addicted to drugs, in research, including primary care, internal medicine and emergency-room physicians. “We will be expanding our reach,” Dr. Trivedi said.

 

ClinicalTrials.gov

**ClinicalTrials.gov has information about federally and privately supported clinical trials, as quoted  news release item above.

Some clinical trials studies post their results at ClinicalTrials.gov.
Check the About page and Understanding Clinical Trials at Clinical Trials.gov for more information.

Related posts

Clinical Trials and Systematic Reviews: Managing Information Overload

Older adults often excluded from clinical trials –  US population ages, need grows for research to improve health and health care for seniors

 

 

February 3, 2011 Posted by | Medical and Health Research News | , , , , , , | Leave a comment

For-Profit Hospices May Prefer Certain Types of Patients: Study

For-Profit Hospices May Prefer Certain Types of Patients: Study
They’re more likely to admit people that require less intense care, but a longer stay

HealthDay news image

 

From a February 1, 2011 Health Day news item

TUESDAY, Feb. 1 (HealthDay News) — End-of-life care facilities run for profit are more likely to have patients who require less-skilled care on the part of the hospice, or patients who need longer times in hospice care, research reveals.

Under the current Medicare reimbursement system — which pays hospices a flat daily rate, regardless of care needs — such patients would likely cost less to care for, according to the study.

“We found that for-profit hospices had more patients with non-cancer diagnoses, especially dementia, that were associated with fewer visits per day from hospice nurses and social workers,” noted the study’s lead author, Dr. Melissa Wachterman, a general medicine research fellow, and a palliative care physician at Harvard Medical School and Beth Israel Deaconess Medical Center in Boston.

“There was a difference in the distribution of diagnoses. Non-cancer diagnoses were more common in for-profit hospices. And, under the current reimbursement system, those patients may be more profitable,” she explained.

More reassuring for families, however, is the finding that patients’ care needs were met in both for-profit and non-profit hospice programs, Wachterman noted.

Results of the study appear in the Feb. 2 issue of the Journal of the American Medical Association….

 

 


February 3, 2011 Posted by | Medical and Health Research News | , , , | Leave a comment

From Biology to Community Library: The Settings for Health

This item helps explain why a healthy and prosperous community/society needs a firm foundation on healthy child development. This firm foundation has many genetic and environmental components.

From  a  February 2, 2011 Redefine.Rebuild.Reconnect. Changing our Picture of Health posting
From biology to a community library: the settings for health, Michelle Helliwell, Librarian

InBrief: The Foundations of Lifelong Health

From [Harvard University] Center on the Developing Child (with links to their 24 videos)

(This blog item/Web page includes a great 7 minute video ,Foundations of Living Health, which outlines how various genetic and environmental factors affect the wellness of both individuals and the society at large)

When we talk about health and healthy living, there seems to be, at times, a division within healthcare (and outside of it) about what are the factors that contribute to your health and wellbeing. Good genes? How well you eat? Whether have a safe neighbourhood to play in? If you take a look at our page on health determinants, you’ll see that all of these, and others, have a role.

Fellow triPop member Sarah Hergett shared  the video …[ (at http://www.changingourpictureofhealth.ca/?p=225) ] … with our group the other day, and it’s worth passing on. It’s a presentation from the Center on the Developing Child at Harvard University. In this seven minute presentation, you’ll find how researches from the fields of neuroscience, biology, and public health present the tangible links between what goes on inside our bodies to how that’s impacted on our health throughout our lives. As a librarian – and an advocate for literacy and health literacy – I was particularly thrilled to see libraries on the list of important resources that contribute to our health. So…support your local library! Support your community. It’s good for your health:).

This quoted blog item/Web page includes a great 7 minute video, Foundations of Living Health, which outlines how various genetic and environmental factors affect the wellness of both individuals and the society at large.

This video summarizes findings from The Foundations of Lifelong Health Are Built in Early Childhood, a report co-authored by the National Scientific Council on the Developing Child and the National Forum on Early Childhood Policy and Programs.

The seemingly disparate health/well being factors include undue emotional stress, consumer products readily available (as liquor, fresh produce), healthy social relationships, parenting, individual genetic make-up, physical environments (think lead, tobacco products), schooling, libraries, government agency policies (as WIC), and employee policies affecting parents and others close to the child.



February 3, 2011 Posted by | Public Health | , , , , | Leave a comment

   

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