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Today's Health News

May 9, 2008

The first Americans ate seaweed, suggesting that colonisation of the continent was slower than archaeologists had thought. The study at the Monte Verde archaeological site in southern Chile, the earliest known human settlement in the Americas, provides additional support for the theory that one route followed by early migrants more than 14,000 years ago was down the Pacific Coast. View of excavated Monte Verde II wishbone-shaped structure thought to be a medicinal hut and containing several masticated cuds. "Monte Verde II" refers to the upper layer of the Monte Verde site. At the time it was inhabited, Monte Verde was situated on a small tributary of a large river, about 400 feet above sea level and located more than 50 miles from the sea and about 10 miles from a large marine bay. Despite its inland location, researchers identified nine different species of seaweed and algae at the site - material that the Monte Verdeans must have brought from the coast. The seaweed samples were dated to between 14,220 to 13,980 years ago by a team led by Prof Tom Dillehay of Vanderbilt University and they report in the journal Science that this confirms that the upper layer of the site, denoted Monte Verde II, was occupied more than 1,000 years earlier than any other reliably dated human settlements in the Americas. "Finding seaweed wasn't a surprise, but finding five new species in the abundance that we found them was a surprise," says Prof Dillehay. Even today, local people use seaweed in the same way. "There are other coastal resources at the site," he adds. "The Monte Verdeans were really like beachcombers: The number and frequency of these items suggests very frequent contact with the coast, as if they had a tradition of exploiting coastal resources." This has implications for how the continent was colonised. "If all the early American groups were following a similar pattern of moving back and forth between inland and coastal areas, then the peopling of the Americas may not have been the blitzkrieg movement to the south that people have presumed, but a much slower and more deliberate process," Prof Dillehay says. "It was not just a straight shot down the coastal highway, so as to speak." "We usually think they moved quickly down the coastal highway following a known and directed route, armed with familiar resources. Yet, they had to traverse many large rivers which require a boat or raft or canoe and in many cases they turned upriver where surely tempting resources were located. Most of the seaweeds were likely collected from one of the sandy beaches west to northwest of the site "And if they became as familiar with the riverine resources as the Monte Verdeans did, it was a much slower movement south." Many of the seaweed fragments were found in areas used for cooking, suggesting the plants were eaten. Others were mixed with plants and chewed into clumps, or "cuds," which may have been used as medicines. The researchers have also found a variety of other beach or coastal resources, including flat beach pebbles, water plants from brackish estuaries and bitumen. The Monte Verde site was discovered by Prof Dillehay and colleagues in 1976. It is located in a peat bog about 500 miles south of Santiago and excavations have revealed the well-preserved ruins of a settlement of up to 30 people living in a dozen huts. Various kinds of food have been found including extinct species of llama and an elephant-like animal called a gomphothere, shellfish, vegetables and nuts. In 1979, when Prof Dillehay and his colleagues first reported radiocarbon dating results of the bones and charcoal there, which returned dates of more than 14,000 years before the present, it stirred controversy because this contradicted other archaeological evidence of the settlement of North America. Since at least 1900, the prevailing theory had been that human colonisation began at the end of the last Ice Age about 13,000 years ago, when groups of big game hunters, called the Clovis culture, followed herds from Siberia to Alaska over a land bridge across the Bering Strait and then gradually spread southward. None of the Clovis artifacts were dated earlier than 13,000 years ago. So having a substantially older human settlement in southern Chile undermined the textbook wisdom. Most scholars now believe that people first entered through the Bering land bridge more than 16,000 years ago and then spread rapidly down the coast. Monte Verde is 14,200-14,500 years old and the general view is that the early immigrants would have moved south along the shoreline much more readily than they moved inland because they could exploit familiar coastal resources and get much of their food from the sea. However, evidence to support the coastal migration theory has been hard to find because sea levels then were about 200 feet lower than today: As the sea level rose, it would have covered most early coastal settlements.

A Real-life I Am Legend? Researcher Champions Development Of "Reovirus" As Potential Treatment For Cancer

Virologist and cancer biologist Patrick Lee was on his way to the American Association of Cancer Research in San Diego last week when he decided to check out the in-flight movie I Am Legend.

The premise of the sci-fi horror movie is that a virus successfully used to fight cancer in clinical trials has gone out of control, pushing humankind to the edge of extinction. Early on in the movie, survivor Robert Neville (Will Smith) replays a three-year-old TV interview which foreshadows the impending disaster.

"So, Dr. Krippin, give it to me in a nutshell," says the TV interviewer.

"Well, the premise is quite simple," responds the scientist. "Um, take something designed by nature and reprogram it to make it work for the body rather than against it."

In his airplane seat, Dr. Lee's jaw is dropping. Not a movie-goer, he didn't catch the movie in theatres when it came out last Christmas, although a colleague at McGill thought he should.

"That's my research. I can't believe it, that's my research," he says. "I was the first one to use a virus to target cancer cells."

Dr. Lee has championed the development of the naturally occurring "reovirus" as a potential treatment for cancer. Reovirus, like all viruses, self-propagates and multiplies when it attaches itself to a host cell. With ordinary viruses, they can cause sickness due to infection. Reovirus, though, kills cancerous host cells and leaves healthy cells alone.

In 1998, Dr. Lee revealed that reovirus injected in mice shrank tumours from brain cancer significantly. Not only that, the reovirus would seek out other tumours and eliminate them as well. His discovery of a promising therapy for cancer was a worldwide sensation when announced in the journal Science.

In the decade since his breakthrough, Dr. Lee relocated from the University of Calgary to Dalhousie University, where he's worked to understand how reovirus replicates in the host cell and seeks out other cancerous cells. In short, says Dr. Lee, "to know what makes the virus such a potent cancer killer."

He's recently received word of a $711,000 grant from the Canadian Institutes of Health Research (CIHR) which will support his laboratory for the next three years; the money is part of more than $4-million in grants from CIHR that are going to Dalhousie University researchers. Ten graduate students and post-doctoral fellows work on two cancer-related projects in Dr. Lee's laboratory: one is the reovirus project; the other involves the function of p53, a tumour-suppressor protein.

Meanwhile, independent of Dr. Lee's research, phase-one and phase-two clinical trials are taking place in the United States and in the U.K. to test the safety and effectiveness of reovirus in humans. Results have been promising so far, says Dr. Lee, but large-scale, phase-three clinical trials are still a few years away.

But clearly the movie is still bothering him. He wants to make it clear there's no worry that the reovirus could run amuck.

"I thought the movie was very entertaining but the scenario it presents is highly unlikely, almost impossible," he says.

With a pause, he adds: "Scientists don't like to deal in absolutes, but in this case, I would say absolutely impossible."

Dalhousie University
Room 218, Second Fl., Henry Hicks Academic Admin Bldg.
Halifax, Nova Scotia B3H 3J5
Canada
http://www.dal.ca

Too Much Or Too Little Weight Gain Poses Risks To Pregnant Mothers, Babies

Radiotherapy Delivery Up To Eight Times Faster, Accuracy Improved With Less Time For Movement

Calling For A Major Shift In HIV Prevention Priorities

Use Of Drink And Drugs By Young People For Better Sex

Brain Imaging Improves Anxiety Treatment

Wouldn't it be nice if our doctors could predict accurately whether we would respond to a particular medication? This question is important because research studies provide information about how groups of patients tend to respond to treatments, but inevitably, differences among groups of patients with the same diagnosis mean that findings about groups of patients may not apply to individuals from those groups. "Personalized medicine" is the effort to match particular treatments to particular patients on the basis of genetic information or other biological markers. In a new article published in Biological Psychiatry, researchers report their findings on the potential use of functional magnetic resonance imaging (fMRI) to match treatments for patients with generalized anxiety disorder (GAD).

Whalen and colleagues recruited subjects diagnosed with GAD who underwent brain scans both before and after treatment with venlafaxine, an antidepressant that has been shown to be effective in treating anxiety. During the fMRI scans, the participants' responses to viewing pictures of fearful facial expressions were measured. Dr. Paul Whalen, corresponding author for this article, explains, "We focused our study on a regulatory circuit in the brain involving the amygdala, an area that serves to detect the presence of threatening information, and the prefrontal cortex, an area that functions to control these threat responses when they are exaggerated or unnecessary."

The researchers found that approximately two thirds of the patients experienced relief from their anxiety symptoms after treatment, and of those who improved, some responded better than others. As hypothesized, the fMRI data predicted who would do well on the drug and who would not. According to Dr. Whalen, "subjects who showed high prefrontal cortex activation together with low amygdala activation in response to the fearful faces reported a significant decrease in their anxiety symptoms, while those showing the reverse brain activation pattern (i.e., high amygdala, low prefrontal) did not."

John H. Krystal, M.D., Editor of Biological Psychiatry and affiliated with both Yale University School of Medicine and the VA Connecticut Healthcare System, comments on this study, "There is a tremendous need for biomarkers of treatment response. The paper by Whalen et al. joins a small group of preliminary studies suggesting that fMRI research might contribute to the effort to develop treatment biomarkers." He cautions, though, that "while these are exciting data, we have yet to see this type of biomarker receive sufficient rigorous validation to be useful for matching patients to existing treatments or to test new potential treatment mechanisms." Dr. Whalen acknowledges the preliminary nature of their findings, noting that "future studies will be needed to determine the exact impact that brain imaging might have in helping physicians prescribe anti-anxiety medications," but he concludes that "while a brain scan would be a relatively expensive addition to the prescribing procedure, this cost pales in comparison to the amount of time, money and angst invested by patients who go through multiple medications and dosages looking for relief."

The article is "A Functional Magnetic Resonance Imaging Predictor of Treatment Response to Venlafaxine in Generalized Anxiety Disorder" by Paul J. Whalen, Tom Johnstone, Leah H. Somerville, Jack B. Nitschke, Sara Polis, Andrew L. Alexander, Richard J. Davidson and Ned H. Kalin. Drs. Whalen and Somerville are affiliated with the Department of Psychological and Brain Sciences, Dartmouth College, Hanover, New Hampshire. Drs. Johnstone, Nitschke, Polis, Alexander, Davidson and Kalin are affiliated with the Departments of Psychiatry and Psychology, University of Wisconsin - Madison and The Waisman Center for Functional Brain Imaging and Behavior in Madison, Wisconsin. The article appears in Biological Psychiatry, Volume 63, Issue 9 (May 1, 2008), published by Elsevier.

About Biological Psychiatry

This international rapid-publication journal is the official journal of the Society of Biological Psychiatry. It covers a broad range of topics in psychiatric neuroscience and therapeutics. Both basic and clinical contributions are encouraged from all disciplines and research areas relevant to the pathophysiology and treatment of major neuropsychiatric disorders. Full-length and Brief Reports of novel results, Commentaries, Case Studies of unusual significance, and Correspondence and Comments judged to be of high impact to the field are published, particularly those addressing genetic and environmental risk factors, neural circuitry and neurochemistry, and important new therapeutic approaches. Concise Reviews and Editorials that focus on topics of current research and interest are also published rapidly.

Biological Psychiatry (http://www.sobp.org/journal) is ranked 4th out of the 95 Psychiatry titles and 16th out of 199 Neurosciences titles on the 2006 ISI Journal Citations Reports® published by Thomson Scientific.

About Elsevier

Elsevier is a world-leading publisher of scientific, technical and medical information products and services. Working in partnership with the global science and health communities, Elsevier's 7,000 employees in over 70 offices worldwide publish more than 2,000 journals and 1,900 new books per year, in addition to offering a suite of innovative electronic products, such as ScienceDirect (http://www.sciencedirect.com/), MD Consult (http://www.mdconsult.com/), Scopus (http://www.info.scopus.com/), bibliographic databases, and online reference works.

Elsevier (http://www.elsevier.com/) is a global business headquartered in Amsterdam, The Netherlands and has offices worldwide. Elsevier is part of Reed Elsevier Group plc (http://www.reedelsevier.com/), a world-leading publisher and information provider. Operating in the science and medical, legal, education and business-to-business sectors, Reed Elsevier provides high-quality and flexible information solutions to users, with increasing emphasis on the Internet as a means of delivery. Reed Elsevier's ticker symbols are REN (Euronext Amsterdam), REL (London Stock Exchange), RUK and ENL (New York Stock Exchange).

Source: Jayne Dawkins
Elsevier

May 8, 2008

Flowers 'wave' at passing insects

Flowers "wave" at insects to get their attention, scientists have discovered.

The finding helps explain why many flowers waft in the breeze, and reveals a hitherto unknown trick used to attract pollinators.

Scientists made the discovery while studying common wildflowers known as sea campion on the Welsh coast.

Mobile flowers are visited more often by insects and also produce more seeds, they report in the Journal of Evolutionary Biology.

Moving flowers also attract a wider variety of insect species than more static blooms.

For years, biologists have known that flowers use striking colours, fragrances, elaborately shaped petals and nectar to attract pollinating insects such as bees and flies.

Yet no-one had ever seriously considered whether wafting in the wind acted as a similar signal.

Beachside inspiration

"I was lying on the beach watching flowers wave in the wind at my daughter's birthday party, and I wondered why they have stalks and risked getting damaged in such an exposed habitat," recounted John Warren from the University of Aberystwyth.

Only flowers that wobble the right amount are successful in setting seeds John Warren

So he looked at what research had previously been done, and found very few answers.

"The only reference I found to motion in attracting pollinators says it's unlikely to be important, because insects are not good at detecting movement; which is clearly rubbish."

To find out more, Dr Warren and colleague Penri James experimented with sea campion (Silene maritima) growing on an exposed coast within a Site of Special Scientific Interest in Cardigan Bay in west Wales.

They observed 300 specially grown flowers of varying stem lengths, recording how much each flower moved in the wind, how often it was visited by insects and for how long, and how many seeds it went on to produce.

Their experiments reveal that flowers mounted on long, thin stalks move around more in the wind.

This acts as a powerful signal to passing pollinators, allowing the plant to attract more insects than less mobile flowers growing atop short, thick stems.

"We found wavy flowers are more visible to insects, and thus attract more pollinators and set more seeds," said John Warren.

But flowers ultimately face an evolutionary trade-off, he believes.

"Short, fat-stalked flowers don't wobble enough and are less attractive to pollinators; yet very wobbly flowers are just too wobbly for the insects to handle, as the insects cannot land on them.

"Only flowers that wobble the right amount are successful in setting seeds."

'Spinach does really help build muscles'

Unfortunately for those looking to increase their muscle mass, the team estimates that humans would have to eat more than 2.2lb (one kilogram) of spinach every day.

Researchers led by Ilya Raskin, from Rutgers University, New Jersey, tested the effect of the extracted chemicals, phytoecdysteroids.

When placed on samples of human muscle in a lab, they sped growth by up to 20 per cent.

Rats injected with the extract for a month were also stronger and had increased grip strength, the study, highlighted by New Scientist, shows.

High in vitamins C, A and K, previous research has suggested that spinach could help people battling weight problems to stay slim, by slowing the digestion of fat and fooling the body into feeling fuller for longer.

Studies have also shown that spinach can help to boost brainpower by keeping the mind alert.

Women can get different heart attack symptoms than men

MIT study suggests caution on new anti-obesity drug in kids

Anti-obesity drugs that work by blocking brain molecules similar to those in marijuana could also interfere with neural development in young children, according to a new study from MIT’s Picower Institute for Learning and Memory.

Marijuana is known to be an appetite stimulant, and a new class of anti-obesity drugs—such as rimonabant (trade name Acomplia) developed by Sanofi-Aventis and awaiting approval for use in the United States—work by blocking brain receptors that bind to marijuana and other cannabinoids.

Marijuana, derived from the plant Cannabis sativa, contains special active compounds that are referred to collectively as cannabinoids. But other cannabinoids (endocannabinoids) are generated naturally inside the body.

The MIT study, which was done in mice, found that blocking cannabinoid receptors could also suppress the adaptive rewiring of the brain necessary for neural development in children. The work is reported in the May 8 issue of Neuron.

“Our finding of a profound disruption of cortical plasticity in juvenile mice suggests caution is advised in the use of such compounds in children,” wrote lead author Mark F. Bear, director of the Picower Institute and Picower Professor of Neuroscience.

The researchers investigated plasticity—the brain’s ability to change in response to experience—by temporarily depriving newborn mice of vision in one eye soon after birth. This well-known experiment induces a long-lasting loss of synapses that causes blindness in the covered eye, while synapses shift to the uncovered eye. How and where this synaptic shift occurs in the primary visual cortex has remained controversial.

Understanding the mechanism behind this phenomenon is key because the same brain mechanisms are used for normal development and may go awry in conditions that cause developmental delays in humans, and may reappear in old age and contribute to synaptic loss during Alzheimer's disease, Bear said.

In mice, the MIT researchers found, even one day of deprivation from one eye starts the shift to dominance of the uncovered eye. But injecting the mice with a cannabinoid receptor blocker halted the shift in certain brain regions, indicating that cannabinoids play a key role in early synaptic development.

Blocking cannabinoids receptors could thwart this developmental process, the researchers said.

This work is supported by the National Eye Institute and the National Institute of Mental Health.

Skin flaps deliver cancer-fighting therapy, ASPS study reveals

Treatment provides 'blueprint' to produce therapeutic proteins at tumor site

ARLINGTON HEIGHTS, Ill. – Using gene therapy, plastic surgeons have delivered cancer fighting proteins through skin flaps placed on cancerous tumors on rats with a 79 percent reduction in tumor volume, according to a study in the May issue of Plastic and Reconstructive Surgery®, the official medical journal of the American Society of Plastic Surgeons (ASPS). This new delivery technique, which has yet to be tested in humans, did not cause toxicity in the body of rats; however, administering the same anti-tumor agent intravenously in humans has previously been shown to cause liver damage.

“This new technique may allow us to reprogram skin flaps, using gene therapy, to provide a blueprint for anti-tumor agents like Interleukin-12 to be produced in the tumor to kill cancer, while avoiding adverse side effects,” said Geoffrey Gurtner, MD, ASPS Member and study senior author. “In this study we took skin flaps in animal models and delivered IL-12 directly to the tumor area with tremendous success. Since skin flaps are used thousands of times each year in cancer patients, this may potentially open up an entirely new area in plastic surgery and bring the specialty, once again, to the center of medicine.”

Gene therapy has been heralded as a new tool to restrain or prevent tumor growth and recurrence in humans, but its use has been limited because of serious side effects and the difficulty in concentrating anti-tumor agents at the site of the cancer.

In the study, skin flaps (a mass of healthy tissue) taken from rats were injected with the gene for IL-12 into the flaps’ blood supply. The flaps were then placed onto cancerous tumors on the rats.

The study found a 79 percent reduction in tumor volume for animals treated with IL-12 compared to control animals. The treatment allowed individual cells within the flap to become encoded with IL-12 and function as “miniature factories” producing the IL-12 protein at very high levels in the tumor site, according to the study.

Additionally, the serious side effects previously documented with systemic use of IL-12 were not found in the treated rats. The liver, lung and spleen remained normal throughout the study. The delivery technique through free flaps did not cause liver toxicity, whereas using IL-12 intravenously in humans has been shown to cause liver damage.

“This could be a major advance for the delivery of a therapeutic agent to diseased parts of the body,” said Dr. Gurtner. “I can see this therapy being used for breast cancer, head and neck cancers, central nervous system malignancies, and somewhere down the line hemophilia, diabetes and infections.”

The study authors concluded that as oncologic reconstructive surgery is a major component of plastic surgery, the delivery of a healing agent precisely to the region where cancer was and where local recurrences are most likely to occur, could add a new dimension to the reconstructive function of free flaps in oncologic and reconstructive plastic surgery.

Nearly 5.2 million reconstructive plastic surgery procedures were performed in 2007, according to ASPS statistics. More than 3.8 million tumor removals and 57,000 breast reconstructions were performed last year.

Visit www.plasticsurgery.org for referrals to ASPS Member Surgeons and to learn more about cosmetic and reconstructive plastic surgery.

The American Society of Plastic Surgeons is the largest organization of board-certified plastic surgeons in the world. Representing more than 6,700 physician members, the Society is recognized as a leading authority and information source on cosmetic and reconstructive plastic surgery. ASPS comprises more than 90 percent of all board-certified plastic surgeons in the United States. Founded in 1931, the Society represents physicians certified by The American Board of Plastic Surgery or The Royal College of Physicians and Surgeons of Canada.

Do antidepressants enhance immune function?

Ex vivo results from HIV positive individuals with and without depression

Philadelphia, PA, May 8, 2008 – Infection with human immunodeficiency virus (HIV), which leads to acquired immunodeficiency syndrome (AIDS), is an epidemic of global concern. According to the most recent estimates, released in November 2007, by the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the World Health Organization (WHO), an estimated 33.2 million worldwide are living with HIV infection currently. Although the rates of infection appear to be decreasing, there are obviously immense implications for achieving improvements in HIV/AIDS treatment.

The functioning of natural killer (NK) cells, which are a major element of the innate immunity system and are involved in the body’s first line of defense against infections such as HIV, is decreased in both HIV and depression. A group of researchers who have previously found that stress and depression impair NK cell function and accelerate the course of HIV/AIDS are now publishing a new report in the May 1st issue of Biological Psychiatry.

In this study, they recruited both depressed and non-depressed HIV-infected women and studied the ex vivo effects of three drugs, a selective serotonin reuptake inhibitor (SSRI), a substance P antagonist, and a glucocorticoid antagonist, on their NK cell activity. These drugs were selected because, as the authors state, each “affect[s] underlying regulatory systems that have been extensively investigated in both stress and depression research as well as immune and viral research.” The scientists found that the SSRI citalopram, and the substance P antagonist CP 96,345, but not the glucocorticoid receptor antagonist RU486, increased NK cell activity. According to Dr. Dwight Evans, corresponding author of the article: “The present findings provide evidence that natural killer cell function in HIV infection may be enhanced by selective serotonin reuptake inhibition and also by substance P antagonism in both depressed and non-depressed individuals.”

John H. Krystal, M.D., Editor of Biological Psychiatry and affiliated with both Yale University School of Medicine and the VA Connecticut Healthcare System, comments: “There has been growing evidence that the compromise of immune function associated with depression influences the outcomes of infectious diseases and cancer. Antidepressant treatments are beginning to be studied for their potential positive effects on immune function.” He adds that “the paper by Evans et al. suggests that antidepressant treatment may have positive effects on natural killer cell activity in cells isolated from individuals infected with HIV with and without depression. This type of bridge between the brain and the rest of the body deserves further attention.” Dr. Evans agrees, noting that “these findings begin to pave the way towards initiating clinical studies addressing the potential role of serotonergic agents and substance P antagonists in improving natural killer cell innate immunity, possibly delaying HIV disease progression and extending survival with HIV infection.”

Notes to Editors:

The article is “Selective Serotonin Reuptake Inhibitor and Substance P Antagonist Enhancement of Natural Killer Cell Innate Immunity in Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome” by Dwight L. Evans, Kevin G. Lynch, Tami Benton, Benoit Dubé, David R. Gettes, Nancy B. Tustin, Jian Ping Lai, David Metzger and Steven D. Douglas. Drs. Evans, Lynch, Benton, Dubé, and Metzger and Mr. Gettes are affiliated with the Department of Psychiatry, with Dr. Evans also with the Departments of Medicine and Neuroscience, and Dr. Douglas is with the Department of Pediatrics, all at the University of Pennsylvania School of Medicine in Philadelphia, Pennsylvania. Ms. Tustin and Drs. Lai and Douglas are with the Division of Allergy and Immunology, Joseph J. Stokes Research Institute of The Children’s Hospital of Philadelphia, in Philadelphia, Pennsylvania. The article appears in Biological Psychiatry, Volume 63, Issue 9 (May 1, 2008), published by Elsevier.

Full text of the article mentioned above is available upon request. Contact Jayne M. Dawkins at (215) 239-3674 or ja.dawkins@elsevier.com to obtain a copy or to schedule an interview.

About Biological Psychiatry

This international rapid-publication journal is the official journal of the Society of Biological Psychiatry. It covers a broad range of topics in psychiatric neuroscience and therapeutics. Both basic and clinical contributions are encouraged from all disciplines and research areas relevant to the pathophysiology and treatment of major neuropsychiatric disorders. Full-length and Brief Reports of novel results, Commentaries, Case Studies of unusual significance, and Correspondence and Comments judged to be of high impact to the field are published, particularly those addressing genetic and environmental risk factors, neural circuitry and neurochemistry, and important new therapeutic approaches. Concise Reviews and Editorials that focus on topics of current research and interest are also published rapidly.

Biological Psychiatry (www.sobp.org/journal) is ranked 4th out of the 95 Psychiatry titles and 16th out of 199 Neurosciences titles on the 2006 ISI Journal Citations Reports® published by Thomson Scientific.

About Elsevier

Elsevier is a world-leading publisher of scientific, technical and medical information products and services. Working in partnership with the global science and health communities, Elsevier's 7,000 employees in over 70 offices worldwide publish more than 2,000 journals and 1,900 new books per year, in addition to offering a suite of innovative electronic products, such as ScienceDirect (http://www.sciencedirect.com/), MD Consult (http://www.mdconsult.com/), Scopus (http://www.info.scopus.com/), bibliographic databases, and online reference works.

Elsevier (http://www.elsevier.com/) is a global business headquartered in Amsterdam, The Netherlands and has offices worldwide. Elsevier is part of Reed Elsevier Group plc (http://www.reedelsevier.com/), a world-leading publisher and information provider. Operating in the science and medical, legal, education and business-to-business sectors, Reed Elsevier provides high-quality and flexible information solutions to users, with increasing emphasis on the Internet as a means of delivery. Reed Elsevier's ticker symbols are REN (Euronext Amsterdam), REL (London Stock Exchange), RUK and ENL (New York Stock Exchange).

Aortic Aneurysm -- Often An Unexpected Diagnosis

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Prostate Cancer Breakthrough Receives FDA Clearance

Secret To Testis Development Lies In Gene Interaction

Infants At Risk For Birth Problems When Mothers' Blood Sugar Levels Are Raised

Pregnant women with blood sugar levels in the higher range of normal - but not high enough to be considered diabetes - are more likely than women with lower blood sugar levels to give birth to babies at risk for many of the same problems seen in babies born to women with diabetes during pregnancy, according to a study funded in large part by the National Institutes of Health.

These problems included a greater likelihood for Caesarean delivery and an abnormally large body size at birth. Infants born to women with higher blood sugar levels were also at risk for shoulder dystocia, a condition occurring during birth, in which an infant's shoulder becomes lodged inside the mother's body, effectively halting the birth process.

The study authors declined to make recommendations for acceptable blood sugar levels for pregnant women. The researchers were unable to identify a precise level where an elevation in blood sugar increased the risk for any of the outcomes observed in the study. Rather, the chances for the outcomes were observed to increase gradually, corresponding with increases in the women's blood sugar levels.

It is well known that high blood sugar levels characteristic of the diabetes that occurs during pregnancy present risks for expectant mothers and the infants born to them. The current study is the first to document that higher blood sugar levels, not high enough to be considered diabetes, also convey these increased risks. Furthermore, when the researchers mathematically adjusted for other potential causes of these risks - such as older maternal age, obesity, and high blood pressure - the increased risks due to higher blood sugar levels were still present.

"These important new findings highlight the risks of elevated blood sugar levels during pregnancy," said Duane Alexander, M.D., director of the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development, which provided much of the funding for the study. "NIH-supported studies now in progress will provide guidance on how to manage them. Until the results of those studies are available, all pregnant women should consult a health care professional about being screened for diabetes during pregnancy."

Additional NIH funding was provided by the National Institute of Diabetes and Digestive and Kidney Diseases, and the National Center for Research Resources.

Diabetes results from difficulty transferring sugar (glucose) from the blood to the body's tissues. It occurs in roughly 5 percent of all pregnancies in the United States. Mothers with diabetes during pregnancy are also at increased risk for preeclampsia, a potentially fatal disorder involving dangerously high blood pressure. Babies born to mothers with diabetes - when they reach adulthood - are at higher risk for obesity as well as diabetes, high blood pressure, and heart disease.

The seven-year study involved more than 23,000 pregnant women at 15 centers in 9 countries.

The results of the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study appear in the May 8 New England Journal of Medicine. The researchers were led by Boyd E. Metzger, M.D. Professor of Medicine at the Northwestern University Feinberg School of Medicine in Chicago.

Dr. Metzger explained that before the current study, physicians were not sure at which point elevated maternal blood sugar posed a risk for the baby. Frequently, high maternal blood sugar levels accompany such conditions as obesity, high blood pressure and older maternal age - all known to increase the likelihood for Caesarean delivery. For this reason, it wasn't known whether the increased risk for Caesarean delivery and other problems seen with mild elevations in blood sugar during pregnancy were caused by the elevated blood sugar levels, or by these accompanying conditions. In their study, however, the researchers made adjustments for these accompanying conditions and found that the higher blood sugar levels still conveyed increased risks.

To conduct the study, the researchers performed an oral glucose tolerance test on each woman, from the 24th through the 32nd week of pregnancy. For the test, the women fasted, after which their blood glucose level was measured. Next, the women drank a glucose solution, and then their blood glucose was measured at predetermined intervals. Women with blood sugar levels high enough to raise safety concerns were referred for treatment and were not included in the study. The remaining women were observed throughout the study until they gave birth.

The researchers found that the higher the mother's blood sugar levels, the greater the chances that they would deliver by Caesarean section. In addition, the higher the mother's blood sugar levels, the more likely the infants were to have high insulin levels and low blood sugar levels at birth. Both conditions indicate exposure to high glucose levels in the womb. Moreover, the higher the mother's blood sugar levels, the more likely the women were to develop preeclampsia, and the more likely their infants were to be born prematurely, and to experience shoulder dystocia. So, for example, women with the lowest fasting blood sugar levels gave birth to abnormally large babies roughly 5 percent of the time, while women with the highest blood sugar level gave birth to large babies 26 percent of the time.

"These relationships are continuous and generally increase incrementally over the range of blood glucose levels we saw in the study," he said.

At a consensus conference that is scheduled to take place June 11 through 13 in Pasadena, Calif., researchers, clinical experts, members of professional organizations and others will discuss the findings and make recommendations based on the data. Information on the conference is available at http://www.iadpsg.org/.

For information on gestational diabetes and links to publications on that topic, see http://www.nichd.nih.gov/health/topics/Gestational_Diabetes.cfm

Information on nutrition during pregnancy is available at http://mypyramid.gov/mypyramidmoms/index.html

The NICHD sponsors research on development, before and after birth; maternal, child, and family health; reproductive biology and population issues; and medical rehabilitation. For more information, visit the Institute's Web site at http://www.nichd.nih.gov/.

The National Institutes of Health (NIH) - The Nation's Medical Research Agency - includes 27 Institutes and Centers and is a component of the U. S. Department of Health and Human Services. It is the primary federal agency for conducting and supporting basic, clinical, and translational medical research, and it investigates the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov/.

Source: Robert Bock
NIH/National Institute of Child Health and Human Development

May 7, 2008

Is beauty an advert for good genes?

Beautiful people are healthier and live longer, according to a study of sex appeal.   High and low symmetry composite faces for macaques, Hadza, and Europeans The discovery has come from research conducted across cultures and species that focused on one trait that earlier work found was attractive: symmetry. No one disputes that symmetrical faces, such as that of Kate Moss, are more attractive. But why? One idea is that the trait is an advert of genetic quality or fertility. An alternative view is that preferences for a symmetrical face arose from cultural factors and say nothing about health, fecundity and other biological factors. Now support for the idea that a symmetrical face is indeed a strong advert of mate ‘quality’ is published today in the journal PLoS One by Dr Anthony Little of the University of Stirling and colleagues. Using mug shots of Europeans, the Hadza of Tanzania, one of the last hunter gatherer cultures, and macaque monkeys, measurements were made and people were asked to judge the masculinity of the most and least symmetric pictures. Whether a member of a troop or a tribe, symmetric males had more masculine facial proportions and symmetric females had more feminine facial proportions. "In humans, if you look at female models, for example, they tend to be pretty symmetric and at the extremes of femininity," Dr Little says. He adds "One good face trait deserves another - symmetric men and women appear to have other good face traits". The findings back the claim that the masculinity/femininity of faces is linked with symmetry and hence advertise quality, that is good genes. Biological quality can mean many things but as symmetry and femininity/masculinity arise during development then one explanation for the findings is that "both traits could advertise quality in terms of resistance to disease, or environmental stresses and that might mean people with these traits are healthier and live longer," says Dr Little. We seek a partner with good looks because this is a biological advert that says good genes are to be found in this particular body to help our own genes thrive in the next generation. He adds that a second paper in the journal Behavioural Ecology shows that people who prefer more symmetric faces prefer more extreme faces, that is a rugged male face or a beautiful feminine female face. Dr Little concludes that "overall our work suggests that symmetry and masculinity in faces signal the same thing and that these signals are present across human populations and also in our non-human primate relatives." The researchers are still collecting data on facial beauty at www.alittlelab.com.

Type of body fat 'boosts health'

Subcutaneous fat often collects on the buttocks and legs

Body fat found under the skin - and particularly on the buttocks - may help reduce the risk of developing type 2 diabetes, research suggests.

The study contrasts this subcutaneous fat with visceral fat, which is wrapped around the organs, and raises the risk of ill health.

It is thought subcutaneous fat may produce hormones known as adipokines which boost the metabolism.

The Harvard Medical School study appears in the journal Cell Metabolism.

The surprising thing was that it wasn't where the fat was located, it was the kind of fat that was the most important variable. Professor Ronald Khan Harvard Medical School

The researchers, who worked on mice, transplanted fat from one part of the animals' body to the other.

When subcutaneous fat was moved to the abdominal area, there was a decrease in body weight, fat mass, and blood sugar levels.

The animals also became more responsive to the hormone insulin, which controls the way the body uses sugar. A lack of response to insulin is often the first stage on the path to type 2 diabetes.

In contrast, moving abdominal visceral fat to other parts of the body had no effect.

Lead researcher Professor Ronald Khan said: "The surprising thing was that it wasn't where the fat was located, it was the kind of fat that was the most important variable.

"Even more surprising, it wasn't that abdominal fat was exerting negative effects, but that subcutaneous fat was producing a good effect."

Previous research has suggested that obese people with high levels of both abdominal and subcutaneous fat are more insulin-sensitive than those with only high levels of abdominal fat.

Professor Khan said it was possible that subcutaneous fat offset the effects of visceral fat.

Dr David Haslam, of the National Obesity Forum, said the finding cast new doubt on the merits of Body Mass Index (BMI) as a way to assess whether somebody was unhealthily overweight, as it did not differentiate between different types of fat.

He said it was still important that people tried to control their weight, as healthy lifestyle choices like a balanced diet and taking exercise would overwhelmingly impact on visceral, and not subcutaneous fat levels.

Women have a tendancy to lay down more subcutaneous fat, particularly on their legs and buttocks than men.

Dr Ian Campbell, medical director of the charity Weight Concern, said: "If there is something about subcutaneous fat which is protective, and actually decreases insulin resistance, this could help open up a whole new debate on the precise role fat has on our metabolism."

Hooray! Wine CAN be good for you...so are you drinking the right stuff?

One of the more cheering health messages that's emerged over the past ten years is that drinking wine in moderation can be good for your health.

Research has found that red wine in particular can lower the risk of heart disease, provide protection against stroke, prevent pancreatic cancer and even stave off potentially-fatal food poisoning bugs such as e.coli, salmonella and listeria.

Yet most of us believe that the health benefits extend to all wine - including white and rosÈ - while others simply assume if it's red, then it must be good.

Unfortunately, this isn't the case, says Professor Roger Corder who conducts research into heart disease at Barts and The London School Of Medicine And Dentistry and is the author of The Wine Diet.

In fact, he says, drink the wrong kind of wine and you could simply be dangerously increasing your alcohol intake - with implications not only for your weight but long term for your liver, and no health benefits.

So which wines are the healthiest?

Here, with Prof Corder's help, we identify the ones that are good for you - and how much you should be drinking.

RED WINE

It has long been acknowledged that red wine can be good for the heart. But certain varieties may be better than others.

Pundits often say it's the resveratrol - a powerful antioxidant which comes from the skins of grapes - that's the good thing about red wine.

But although in laboratory conditions it does appear to have anticancer, anti-inflammatory and anti-clotting properties, you would have to drink vast amounts of red wine on a daily basis to reap those health benefits.

Far more important are polyphenols, the chemical compounds in grape skin and seeds.

These are natural antioxidants which protect the membranes of each cell.

Another important element of red wine are procyanidins, which help to reduce blood pressure, lower cholesterol and protect against hardening of the arteries.

The most procyanidin-rich wines tend to be those in which the grapes - including skins and seeds - have remained in contact with the wine during fermentation and afterwards.

Such information is seldom seen on wine bottles - you'd find it by scouring producers' websites (look for contact time of at least ten days for good amounts of procyanidins).

Two wine-growing regions which boast high concentrations of procyanidins are the Nuoro province in Sardinia (which produces the Cannonau grape), and Madiran in the Pyrenees.

Wines from these areas contain up to ten times more beneficial compounds than their counterparts from Australia, South Africa and the United States.

"It's no wonder that the Madiran area has double the French national average of men aged 90, and this is despite regularly eating foods high in saturated fat, such as cassoulet," says Prof Corder.

In fact, one small glass of a Madiran wine can provide more health benefits than two bottles of most Australian wines, without the obvious danger of excessive alcohol consumption.

Other red wines that have a relatively high level of procyanidin include certain types of Cabernet Sauvignon (see Healthier Choice, below) and wines containing Nebbiolo grapes.

HEALTHIER CHOICE: Look for wines from the Madiran and CÙtes de Saint Mont regions of France and from the Sagrantino and Nebbiolo regions of Italy.

Cabernet Sauvignon is generally better than Merlot or Shiraz, with Chilean and Argentinean Cabernets the best choice. Pinot Noir is generally a poor choice as it's low in procyanidins.

WHITE WINE

The main difference between white and red wine is how the skin of the grape is used.

With red, the skins are crushed along with the pulp. In white, the skins are quickly separated out.

However, white wine can still have health benefits as there are other types of polyphenols in the grape itself which could lower levels of 'bad' cholesterol.

Last year, Italian scientists found that both red and white wines are effective anti-bacterial agents against strains of streptomorecoccus, which causes infections such as sore throats.

They put this down to acids in the wine which can protect against and destroy bacteria, but red is better at this than white.

White wine also contains potassium which may help lower blood pressure (though the same amount could be derived from drinking fruit juice), and prevents the creation of molecules which can damage lung tissue.

Because white wine contains the compounds tyrosol and caffeic acid, which act as anti-inflammatories and antioxidants, scientists at the University of Milan believe it could help prevent rheumatoid arthritis and osteoporosis.

They said two glasses a day could produce a reduced inflammatory reaction, but higher consumption cancelled out these benefits.

Other researchers have found that Chardonnay is highest in antioxidants known as polyphenols, while Sauvignon Blanc has anti-inflammatory properties.

Research by Italian and American researchers found that consumption of white wine protects against heart attacks.

Their study featured three wines: two Tocai and a Verduzzo from the Friuli Venezia region of Italy.

On the downside, white wine can make your stomach secrete more acid than normal, which can lead to nausea.

White wines such as Reisling and Pinot Grigio also tend to be sweeter and thus have calories. However, white wine is the preferred option for migraine sufferers since it is low in the headache-inducing compound tyramine, unlike many red and rosÈ wines.

Incidentally, if you're wondering why white wine is less likely to cause a hangover, it's because it lacks congeners - chemicals produced during fermentation.

HEALTHIER CHOICE: Chardonnay, Sauvignon Blanc. Look for wines from the Friuli Venezia region of Italy.

ROSE

Unlike red wine, rosÈ is generally made from a relatively short contact between the liquid and the grape seeds and skins, so it has fewer health benefits than red.

However, taken as part of moderate alcohol consumption, rosÈ can have benefits.

A recent Danish study concluded that people who drink up to two and a half bottles of wine a week - roughly two glasses a day - have a lower risk of premature death than those who abstain from alcohol.

Researchers also found that being physically active and drinking a moderate amount of alcohol is important for lowering the risk of fatal ischaemic heart disease.

ALCOHOL-FREE WINE

This is made in the same way as normal wine, except the alcohol is removed after initial fermentation.

As well as removing the health risks associated with alcohol - such as mouth and throat cancer - alcohol-free wine may provide added protection against disease.

A study by the University of Glasgow found that purple grape juice was the most effective at preventing heart disease and cancer.

It had the highest concentration of antioxidants - chemicals which help to neutralise harmful oxygen molecules called free radicals - of all varieties of fruit juice.

If left unchecked, these molecules can harm cells, and so play a part in everything from ageing to cancer.

ORGANIC WINE

The grapes used are not sprayed with chemicals or pesticides, which have been linked to cancer, though there is no conclusive evidence.

Organic wines contain fewer preservatives known as sulphites which have been linked to asthma and respiratory problems.

Wines labelled 100 per cent organic should be free from sulphites.

NanoViricides, Inc. (OTC BB: NNVC.OB), said that its anti-HIV drug candidates demonstrated significant therapeutic efficacy in the recently completed preliminary animal studies

The studies were performed at a Bio-Safety Level 3 Laboratory (BSL-3) facility in Boston, MA. These mouse model studies were conducted by Dr. Krishna Menon, PhD, VMD, MRCS, a world-renowned authority in preclinical and toxicological studies of innovative therapeutics.

"Dr. Menon has indicated to us that the results of the study validate the Company's HivCide-I as a potential treatment for HIV/AIDS," said Eugene Seymour, MD, MPH, CEO of NanoViricides, adding, "Over the next several weeks, we expect to release additional study data." The Company's scientists are now designing the protocol for a follow up anti-HIV study to be performed at a major United States government research facility.

The Company also said that animal studies for its drug candidates against bird flu (H5N1) are due to be scheduled at a major United States government research facility. The company has previously reported that animal studies against Ebola would be undertaken following the success of in vitro studies. These studies are continuing.

NanoViricides, Inc. is using injectable nanoviricides for its initial HIV studies. Future plans call for the development of a long-acting anti-HIV skin patch. The Company feels that this delivery method will result in markedly improved patient compliance.

About NanoViricides

NanoViricides, Inc. is a development stage company that is creating special purpose nanomaterials for viral therapy. The Company's novel nanoviricide™ class of drug candidates are designed to specifically attack enveloped virus particles and to dismantle them. The Company is developing drugs against a number of viral diseases including H5N1 bird flu, seasonal influenza, HIV, hepatitis C, rabies, dengue fever, and Ebola virus, among others.

This press release contains forward-looking statements that reflect the Company's current expectation regarding future events. Forward-looking statements involve risks and uncertainties. Actual events could differ materially and substantially from those projected herein and depend on a number of factors. Certain statements in this release, and other written or oral statements made by NanoViricides, Inc. are "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These forward looking statements are subject to known and unknown risks, uncertainties and other factors that may cause actual results, performance, or achievements of the company to be different from those expressed or implied including the success of the Company's research and development efforts, the availability of adequate financing, the successful and timely completion of clinical studies and the uncertainties related to the regulatory process, described in the "Management's Discussion and Analysis" section of the Company's Form 10-KSB and other reports and filings with the Securities and Exchange Commission.

NanoViricides, Inc.

AFTER DIVORCE, STABLE FAMILIES HELP MINIMIZE LONG-TERM HARM TO CHILDREN

COLUMBUS, Ohio – For children of divorce, what happens after their parents split up may be just as important to their long-term well-being as the divorce itself.

A new study found that children who lived in unstable family situations after their parents divorced fared much worse as adults on a variety of measures compared to children who had stable post-divorce family situations.

“For many children with divorced parents, particularly young ones, the divorce does not mark the end of family structure changes – it marks the beginning,” said Yongmin Sun, co-author of the study and associate professor of sociology at Ohio State University’s Mansfield campus.

The study appears in a recent issue of the Journal of Marriage and Family.  Sun conducted the study with Yuanzhang Li of the Allied Technology Group.

Data for this study came from the National Education Longitudinal Study, which surveyed thousands of students across the country beginning in 8th grade in 1988, when they were about 14 years old.  They were surveyed again in 1990, 1992 and then again in 2000 when they were about 26 years old.

The study compared children who grew up in three different situations:

• Children who grew up in always-married households (5,303 children).
• Children whose parents divorced before the study began, but who lived in a stable family structure between ages 14 and 18(954 children).
• Children whose parents divorced prior to the beginning of the study, and whose family situation changed once or twice between ages 14 and 18(697 children).

In the two divorced family groups, children may have lived in single-parent families or ones with a stepparent.  The key for this research was whether that arrangement – whichever it was -- changed between ages 14 and 18).

The researchers compared how children in these groups fared on measures of education, income and poverty in 2000 when they were 26.

Results showed that young adults who grew up in stable post-divorce families had similar chances of attending college and living in poverty compared to those from always married families.  But they fared less well on measures of the highest degree obtained, occupational prestige and income.

However, the young adults who lived in unstable family situations after their parents divorced did worse on all measures.  In fact, they fared more than twice as poorly on most measures compared to their peers who had stable family situations.

For example, adults from stable post-divorce families earned about $1,800 a year less than similar adults from always-married families.  But those adults whose family situations changed one or more times between ages 14 and 18 earned about $4,600 less.

Sun noted that some of the children in the unstable family group also underwent a custody change between ages 14 and 18.  An analysis showed that they did not fare significantly differently from those who were in unstable families, but did not experience a custody change.

There were also no significant differences between how boys and girls responded to family stability after a divorce, Sun said.

Why do children of divorce fare less well than those who grew up with parents who stayed married?

This study found that for those in stable post-divorce families, the difference in adult well-being was mostly due to a shortage of economic and social resources.  Compared to always-married parents, divorced parents had a lower level of income, didn’t talk to their children as much about school-related matters, had fewer interactions with other parents, and moved their children to new schools more often.

“As many previous divorce studies point out, divorce reduces social resources within families because children have fewer interactions with the non-custodial parent, and in many cases, don’t get the quantity and quality of parenting from the custodial parent,” Sun said.

“In addition, after a family disruption, parents may not invest as much time with teachers and other parents in the community, all of which lead to a lower level of child well-being.”

For children in unstable families, the decline in social and economic resources was only part of the reason for the shortfalls they experienced in adulthood.

“These children probably experience a lot of stress and disruption from sources that we didn’t measure in this study,” he said.

These findings provide a clear message about how parents who are divorcing can best help their children, Sun said.

“A stabilized post-divorce family environment is clearly helpful for children, particularly for adolescents, such as those we studied, because stability allows children to focus on their own developmental needs rather than on continual family crises,” he said.

The study was supported by grants from the Ohio State University Initiative in Population Research and a population research center grant awarded by the National Institute of Child Health and Human Development.

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Contact:  Yongmin Sun, (419) 755-4261; Sun.84@osu.edu
Written by Jeff Grabmeier, (614) 292-8457; Grabmeier.1@osu.edu

New Evidence-Based Guidelines For Antidepressants

A new revision of clinical guidelines to help doctors manage patients with depression has challenged the rationale behind the UK government's policy of rolling out of cognitive behavioural therapy (CBT) for milder depression.

According to a comprehensive review of treatments for depression, there is a lack of evidence for CBT being more helpful than other forms of psychological support in mild depression or for its efficacy in severe depression. There is also good evidence for antidepressants being effective in depression, with benefit increasing the more severe the depression. This is contrary to recent reports that antidepressants don't work except in the most severe depression.

Dr Ian Anderson, Senior Lecturer and Honorary Consultant Psychiatrist, Neuroscience and Psychiatry Unit, University of Manchester, UK, says the cost effectiveness of CBT should be thoroughly investigated before it is adopted more widely because it is likely to be offered to people with milder depression where the evidence is poorest.

"There is often not a level playing field in considering evidence for drugs versus psychological treatment, especially in milder depression," Dr Anderson explains, adding that specific psychological treatments are relatively expensive compared to drug treatments because treatment involves training of the therapists as well as the costs of administering the intervention.

To measure the effectiveness of these treatments requires "comparison against appropriate control treatment like non-specific supportive treatment in the same way drugs are compared against placebo," says Dr Anderson. "This is important given the rolling out of CBT for milder depression - probably less expensive means of support are more cost-effective."

This conclusion is just one of the issues to emerge from a comprehensive review of the evidence for various forms of management of depression, conducted as part of a revision of the 2000 British Association for Psychopharmacology evidence-based guidelines, and published this week by SAGE in the Journal of Psychopharmacology. The aim of the review was to incorporate new evidence and to update the recommendations where appropriate.

Revisions to the guidelines were agreed after a consensus meeting involving experts in depressive disorders and their management, user representatives, and medical and scientific staff from pharmaceutical companies in May 2006 and a subsequent literature review.

The new guidelines also question whether CBT should routinely be combined with antidepressant medication for depression in adolescents - as the UK's National Institute for Health and Clinical Excellence suggests - citing a lack of evidence. Dr Anderson says some recommendations run contrary to NICE guidance:

• First, the choice between antidepressant