The Lancet (C) 2001 The Lancet. via ProQuest Information and Learning Company; All Rights Reserved Love, Rebecca Dehydroascorbic acid (DHA), a precursor of vitamin C, has cerebroprotective effects in a mouse model of stroke according to a new study from the USA. "These results suggest that an antioxidant precursor that readily penetrates the bloodbrain barrier has promise in the treatment of stroke in humans", says Sander Connolly (Columbia University, NY, USA), one of the investigators. Judy Huang and colleagues compared the effects of vitamin C and DHA on cerebral ischaemia induced by transient or permanent middle cerebral artery occlusion in mice. They found that pretreatment with DHA immediately prior to a reversible (45 min) occlusion significantly reduced infarct volume, increased post-ischaemic blood flow and reduced neurological deficit; pretreatment with vitamin C had no effect. Similarly, pretreatment with DHA protected against permanent (24 h) occlusion, although the effects were less marked. The investigators also found that giving DHA 15 min or 3 h after the ischaemic period was protective, suggesting that antioxidant depletion contributes to neuronal damage following ischaemia (Proc Natl Acad Sci 2001; 98: 117 2024).

Keyword: Stroke; Hormones & Behavior
Link ID: 768 - Posted: 10.20.2001

Bruce Bower An unprecedented genetic find has emerged from an extended British family in which more than half the members display a severe speech and language disorder. Scientists have now identified a genetic mutation that lies at the root of this family's communication breakdown. This is the first gene implicated in people's capability to talk and to understand language, according to a team led by geneticist Cecilia S.L. Lai of the University of Oxford in England. She and her colleagues describe their discovery in the Oct. 4 Nature. "It's exciting that we've found a mutation common to every family member with this disorder," says study coauthor Faraneh Vargha-Khadem, a neuroscientist at the Institute of Child Health in London. "This mutation may impede development of brain areas that mediate speech and language use." From Science News, Vol. 160, No. 14, Oct. 6, 2001, p. 213. Copyright ©2001 Science Service. All rights reserved.

Keyword: Language; Genes & Behavior
Link ID: 767 - Posted: 10.20.2001

by J. Wesley Boyd, M.D., Ph.D., and Karen Lasser, M.D. Psychiatric Times October 2001 Vol. XVII Issue 10 Those who suffer from mental illness smoke cigarettes at astoundingly high rates compared to those without some form of mental illness. We have published data showing that between 50% and 80% of those suffering from a major mental illness (such as major depression, bipolar disorder, generalized anxiety disorder and schizophrenia, among others) smoke, whereas less than 40% of those who have never had mental illness smoke (Lasser et al., 2000). In all, people with mental illness consume 44% of all cigarettes in the United States, an exceedingly high figure that might surprise even the most sanguine mental health care professional. This statistic bears within it numerous individual stories of pain and suffering. Consider the case of one of our patients, whose woeful story no doubt mirrors that of many others we treat who suffer with chronic mental illness:

Keyword: Drug Abuse
Link ID: 766 - Posted: 10.20.2001

by Marc N. Potenza, M.D., Ph.D., and Mary K. Wilber Psychiatric Times October 2001 Vol. XVII Issue 10 Pathological gambling (PG) represents a growing public health concern (Potenza et al., 2001a). As compared with other major neuropsychiatric disorders with similar prevalence rates (e.g., schizophrenia and bipolar disorder), relatively few investigations have been performed about the pathophysiology or treatment of PG (For more information on the history and background of PG, please visit www.psychiatrictimes.com/srpg.html -- Ed.) In order to advance current treatment standards, an improved understanding of the biological processes underlying PG is needed. One major theory proposes that PG is a non-chemical addictive disorder (Blanco et al., 2001; Potenza, 2001; Potenza, in press). Given the shared features between PG and substance dependence (SD) and the significant advances made over the past several decades in our understanding of SD, there exists a useful platform on which to base studies of PG to investigate for similarities and differences between SD and PG (Potenza, 2001).

Keyword: Drug Abuse
Link ID: 765 - Posted: 10.20.2001

To survive in utero, the fetus must resist an onslaught by the mother's immune system that, most researchers agree, recognizes the father's share of the embryo as foreign and sometimes rejects it. Now, endocrinologists have determined that the principal soother of the maternal immune system is the same master hormone that commands the body's stress response. The results could help explain some infertility and recurring miscarriages. Immunologists have long speculated that hormone changes early in pregnancy somehow alter the mother's immune system, but they couldn't pinpoint the mechanism. In the early 1990s, pediatric endocrinologist George Chrousos and his colleagues at the National Institute of Child Health and Human Development in Bethesda, Maryland, came across a clue. They found that corticotropin-releasing hormone (CRH), secreted by the hypothalamus to induce secretion of stress hormones by the pituitary and the adrenal glands, also appeared around sites of inflammation in adults. Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Hormones & Behavior; Development of the Brain
Link ID: 763 - Posted: 10.20.2001

Investigators seek to understand the molecular mechanisms of taste By Jennifer Fisher Wilson By design, humans crave sweet-tasting foods, which supply necessary calories, and avoid bitter-tasting foods, which could be poisonous. But an individual's genetic makeup can acutely tune taste buds. Visitors to Linda Bartoshuk's Yale University lab can take a simple taste test to discover genetic influences on their food intake. The test measures sensitivity to the chemical 6-n-propyl-thiouracil, which is intensely bitter to acute taste buds, moderately bitter to a medium taste bud, and tasteless to an insensitive bud. Sensitive tasters, or supertasters, generally have more taste buds--and they are often women. To them, vegetables are more bitter, fats creamier, and chili peppers hotter. Conversely, nontasters are more likely to eat excessively sweet, very fatty, and highly spiced foods. The Scientist 15[20]:18, Oct. 15, 2001 © Copyright 2001, The Scientist, Inc. All rights reserved.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 762 - Posted: 10.20.2001

Definitive answers about ERT effects are down the road By Harvey Black While estrogen replacement therapy shows promise in helping post-menopausal women preserve important cognitive abilities such as memory, its effectiveness is still being questioned. In studies at the National Institutes of Health and at the University of California, Los Angeles, researchers have demonstrated that in some women, this hormone alters brain blood flow and improves performance on certain mental tests. But other studies are not as definitive, suggesting that improved cognitive abilities could be associated with a decrease in menopausal symptoms. "The epidemiologic data we have is not that mature," says Stanley Birge, clinical director of the Older Adult Health Center at Washington University. "But I think if you add up the negative studies and the positive studies, it does fall to the side of recommending. It probably is effective in preserving the brain." But don't advise treatment right now, some researchers say. "Not yet," says Pauline Maki, an investigator with the National Institute on Aging. "There haven't been any [looks] at large numbers of women on cognitive outcomes." The Scientist 15[20]:21, Oct. 15, 2001 © Copyright 2001, The Scientist, Inc. All rights reserved.

Keyword: Hormones & Behavior; Alzheimers
Link ID: 761 - Posted: 10.20.2001

Hazel Muir Catching the eye of someone beautiful triggers a flurry of activity deep in the brain, new research has found. The discovery may shed light on why first impressions last when we meet new people. Evidence is growing that in animals, a region of the brain called the ventral striatum becomes active when the animal anticipates a reward of food. The same region becomes active in drug addicts and compulsive gamblers when they are about to indulge their habit. Knut Kampe of University College London and his colleagues wondered whether a social "reward" - the sight of an attractive face - would have the same effect. To find out, they scanned the brains of eight men and eight women as they looked at 160 photos of 40 different people in quick succession. The volunteers then rated how attractive they found the faces they had seen. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Brain imaging
Link ID: 760 - Posted: 10.20.2001

by Lucy Yardley, M.Sc., Ph.D. Psychiatric Times October 2001 Vol. XVII Issue 10 Dizziness is a very common symptom, with a lifetime prevalence of about one in four of the general population (Kroenke, 1992). Patients usually use the term dizziness to describe the disorientation and imbalance that result from abnormal balance system functioning, which is most commonly caused by a vestibular disorder. But dizziness is a non-specific symptom that patients also use to describe different sensations -- for example, lightheadedness or mental confusion -- which result from quite different etiologies, such as a cardiovascular or psychiatric disorder. It is often difficult either to confirm or exclude an organic diagnosis for dizziness because of the extensive range of possible etiologies, the lack of definitive exhaustive tests of balance system function, and the transient and ambiguous nature of signs and symptoms. Differential diagnosis of organic versus psychogenic dizziness is further complicated by the very high prevalence of anxiety, panic disorder and agoraphobia among people with diagnosed balance disorders (Clark et al., 1994; Stein et al., 1994; Sullivan et al., 1993; Yardley et al., 1998b) and the unexpectedly high prevalence of balance system dysfunction in patients with panic disorder and agoraphobia that can be detected by sensitive tests (Jacob et al., 1996; Yardley et al., 1995a).

Keyword: Emotions
Link ID: 759 - Posted: 10.20.2001

by Christine E. Marx, M.D., M.A. Psychiatric Times October 2001 Vol. XVII Issue 10 The term neurosteroid refers to steroids formed in the brain. It was created in 1981 by Dr. Etienne-Emile Baulieu and colleagues, following the remarkable discovery that the brain appeared to have the capacity to synthesize its own steroids in situ. In a set of rodent experiments, these researchers determined that the steroid dehydroepiandrosterone sulfate (DHEAS) was present in adult rat brains at concentrations up to 20-fold greater than plasma (Corpechot et al., 1981). Moreover, brain DHEAS concentrations persisted unchanged for over two weeks following adrenalectomy and gonadectomy in these animals, demonstrating that central nervous system DHEAS levels were likely independent of peripheral DHEAS formation in the adrenals or gonads. Hence, the brain itself appeared to be a potential site of steroidogenesis, and subsequent efforts confirmed this possibility. These molecules became known as neurosteroids, since they can be synthesized de novo in the brain from cholesterol or from peripheral steroid precursors that cross the blood-brain barrier readily. A closely related term, neuroactive steroids, includes steroids formed in the brain and periphery that exhibit rapid actions on neuronal excitability. Unlike classical steroid mechanisms that involve the binding of intracellular receptors and the regulation of gene transcription, neuroactive steroids have nongenomic actions (Paul and Purdy, 1992). Specifically, neuroactive steroids bind to membrane-bound ligand-gated ion channel receptors. As a result, their actions occur very rapidly (over the course of seconds to minutes), in contrast to steroid genomic actions that require hours to days. Interestingly, certain neuroactive steroids with rapid nongenomic effects, such as progesterone, also exhibit traditional genomic steroid actions. Progesterone is considered to be a neurosteroid if it is synthesized in the brain, hence, the terms neurosteroid and neuroactive steroid are often used interchangeably.

Keyword: Hormones & Behavior; Emotions
Link ID: 758 - Posted: 10.20.2001

by John DeQuardo, M.D. Psychiatric Times October 2001 Vol. XVII Issue 10 For almost a century, researchers have suggested that schizophrenia is the result of brain-based abnormalities (Kraepelin, 1919). The first structural neuroanatomic studies conducted in patients with schizophrenia were undertaken in the 1930s and 1940s using pneumoencephalography -- a radiologic technique wherein cerebrospinal fluid (CSF) is replaced by air, thereby facilitating X-ray imaging of the brain ventricular system. These early investigations demonstrated lateral ventricle enlargement in some patients with schizophrenia (Haug, 1962). A few investigators found evidence of progression of ventricular enlargement in severely ill patients; however, technical factors involved in image acquisition limited the veracity of the results. The first computed tomography (CT) scan study in patients with schizophrenia was published in 1976 by Johnstone et al. The researchers found that, in chronically ill patients, ventricle enlargement was common and most pronounced in those patients who were most ill (i.e., had the most negative symptoms). Since that time, dozens of studies have replicated the finding of ventricular enlargement in schizophrenia (as well as findings of cerebral cortical atrophy) (Shelton and Weinberger, 1986), some found evidence for progression (Illowsky et al., 1988; Nasrallah et al., 1986), while others did not (Kemali et al., 1989; Woods et al., 1990). The discrepancy in results is very likely the result of methodologic differences between studies.

Keyword: Schizophrenia
Link ID: 757 - Posted: 10.20.2001

Eight years after identifying the first gene responsible for inherited cases of Lou Gehrig's disease, scientists have found another one. Currently there is little hope for those suffering from the neurodegenerative disease that led to the death of Baseball Hall of Famer Lou Gehrig. Scientists hope that this latest finding could help clarify how the disease destroys the central nervous system. Formally known as amyotrophic lateral sclerosis (ALS), Lou Gehrig's disease usually strikes people in their 40s or 50s. Neurons in the brain and spinal cord that control muscles degenerate, eventually killing those affected. The cause of most ALS cases remains a mystery, but about 10% are inherited, and in 1993, scientists found that a gene called SOD1 was mutated in a fifth of these cases. Now, two teams have independently pinpointed a second culprit gene that accounts for some of the other inherited ALS cases. = Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: ALS-Lou Gehrig's Disease ; Genes & Behavior
Link ID: 756 - Posted: 10.20.2001

In the absence of leptin signaling, mice, like humans, grow extremely obese and develop many of the common sequellae of obesity in humans, such as diabetes and steatosis of the liver. Introduction of leptin directly into the hypothalamus potently reverses the overeating and obesity seen in leptin-deficient animals. Still, expression of the leptin receptor ObR is not limited to the hypothalamus and other regions of the brain, but also occurs in the liver and many other sites. Hence, the possibility remains that some of aspects of the leptin-deficient phenotype reflect the absence of peripheral signaling. To test the significance of various sites of central and peripheral leptin signaling, Cohen et al. have used Cre-lox technology to generate mice in which particular cell types delete the ObR gene by somatic recombination. Here, they describe the effects of ObR deficiency in the brain or the liver. Absence of neuronal ObR greatly increases body weight and induces the accumulation of fat in the liver, effects that are not seen when the ObR defect is restricted to the liver. Because obesity in the brain-specific knockout is not as severe as that in simple knockouts, it may be that OBR signaling in organs helps regulate energy homeostasis?effects that may still be revealed in other Cre/lox experiments . However, the authors note that there was considerable scatter in their data and that those animals that had most efficiently removed the ObR gene from their neurons weighed the most. The complete absence of neuronal ObR might, if it could be achieved using this technology, might therefore recapitulate all of the effects observed in Ob- or ObR-deficient animals.

Keyword: Obesity
Link ID: 755 - Posted: 10.20.2001

Michael W. Schwartz Obesity, insulin resistance, and type 2 diabetes are a tightly linked and increasingly common triad of metabolic disorders. A well-supported and widely accepted explanation for their association is that obesity-induced insulin resistance in tissues such as muscle, liver, and fat increases the demand for insulin, and that type 2 diabetes ensues when this heightened demand cannot be met by defective pancreatic ß cells. Despite the undeniable importance of adipocytes in the regulation of insulin sensitivity (see refs. 1-3 for recent reviews and insights into this interaction), this understanding of the pathogenesis of type 2 diabetes may yet be incomplete. Growing evidence suggests that the CNS plays a key role in glucose homeostasis, via brain pathways that overlap with those controlling food intake and body weight. Advancing this notion a step further is the study by Obici et al., published in this issue of the JCI (4), implicating a specific hypothalamic neuronal pathway - the melanocortin pathway - in the control of insulin sensitivity in peripheral tissues. The recognition that neuronal melanocortin signaling also figures prominently in energy homeostasis, the process whereby energy intake is matched to energy expenditure over time, suggests an intimate coupling of neuronal mechanisms regulating body weight and glucose metabolism (Figure 1). Disorders affecting key neuronal pathways can therefore be included among potential mechanisms linking obesity to type 2 diabetes (5).

Keyword: Obesity
Link ID: 754 - Posted: 10.20.2001

A study led by a UCSF and Kaiser Permanente researcher examined the differences in treatment outcomes between integrated and independent models of medical care and substance abuse treatment, and concluded that not only do patients benefit from integrated medical and substance abuse treatments, but the integration can also be cost effective. Medical care is seldom provided as part of substance abuse treatment; and medical and substance abuse services are often separate and uncoordinated, the lead author said. However, there are some substance abuse-related medical conditions (SAMC) requiring treatment including hypertension, coronary artery disease, chronic liver disease, hepatitis C and psychiatric conditions including depression and anxiety disorders.

Keyword: Drug Abuse
Link ID: 753 - Posted: 10.20.2001

By BARNABY J. FEDER Since the World Trade Center bombing in 1993, Dr. Lawrence A. Farwell has been arguing that terrorist operations can be investigated through careful monitoring of the brain waves emitted by suspects during interrogation. The claim did not get very far with the Federal Bureau of Investigation or any other major law enforcement agency then. Now, since the Sept. 11 terrorist attacks, Dr. Farwell and a number of supporters are pressing for a much more thorough consideration. Their effort is another instance of the typical innovator's natural impulse to dress up old visions in front- page news. But Dr. Farwell's investigative technique, which he likes to call brain fingerprinting, may also be seen as a typical story of conflict over how to develop real-world applications from promising bodies of research. Dr. Farwell's concept is an offspring of a vast body of research on the electrical activity of the brain. Most of the research has focused on easily observed phenomena like alpha and beta waves, which have been respectively linked to activities including sleep and heightened alertness. But one subset beginning in the mid-1960's homed in on extremely brief electrical wave patterns associated with recognition of familiar sounds, smells and sights. Copyright 2001 The New York Times Company

Keyword: Brain imaging
Link ID: 747 - Posted: 10.20.2001

One single amino acid determines the binding of CRF/ Synthesis of selective inhibitors for the research on anxiety and memory facilitated In the journal Proceedings of the National Academy of Sciences (September 25, 2001, Vol. 98) scientists of the Max Planck Institute of Experimental Medicine, Goettingen, report about their discovery of an amino acid-switch of the stress hormone corticotropin-releasing factor (CRF): by replacing a single amino acid, they were able to change selectively the binding properties of CRF. On the basis of this observation, the development of selective CRF-like agonists and antagonists should be facilitated.

Keyword: Emotions; Hormones & Behavior
Link ID: 746 - Posted: 10.20.2001

COLUMBUS, Ohio - Depression doesn't solely explain the relationship between panic disorder and suicide, new research suggests. Several studies in recent years have suggested that people with panic disorder are more likely to attempt suicide than patients with other psychiatric conditions. One explanation was that panic disorder, when combined with clinical depression, made people more prone to suicide. The study appears in a recent issue of the journal Behaviour Research and Therapy.

Keyword: Depression; Emotions
Link ID: 745 - Posted: 10.20.2001

CINCINNATI -- A Children's Hospital Medical Center of Cincinnati study to be presented on Monday, October 8, shows that if efforts to prevent childhood obesity are to be successful, the well-being of mothers needs to be addressed. The study shows that both maternal depression and maternal obesity affect the amount of time their preschool children watch television. Excessive TV watching has been linked to childhood obesity. The researchers surveyed 150 low-income mothers of preschool children. These mothers reported that their children watched an average of two hours of TV a day.

Keyword: Obesity
Link ID: 744 - Posted: 10.20.2001

A second gene mutation that causes an inherited form of amyotrophic lateral sclerosis (ALS), or Lou Gehrig's disease, has been identified by Teepu Siddique, M.D., the Northwestern University researcher who, with collaborators from Massachusetts General Hospital, discovered the first ALS gene (ALS1) in 1993. ALS is a terminal, progressive neuromuscular disease that renders the muscles of the body useless while leaving the mind unaffected. There is currently no effective treatment or cure for ALS. The newly identified gene mutation is responsible for a rare, slowly progressive, early-onset form of the disease, called juvenile inherited ALS (ALS2), discovered in highly inbred populations in North Africa and the Middle East. Siddique and colleagues discovered the gene, located on chromosome 2q33, in four Tunisian and Saudi Arabian families. They first identified the location of the gene in 1994. Siddique and an international consortium of researchers reported the discovery of the aberrant gene in the Oct. 3 issue of Nature Genetics. Their findings also clarify why clinicians previously confused ALS2 for another neurodegenerative disease called juvenile primary lateral sclerosis -- different mutations in the same gene are found in both individuals with ALS2 and those with juvenile primary lateral sclerosis, indicating that these conditions have a common genetic origin.

Keyword: ALS-Lou Gehrig's Disease ; Genes & Behavior
Link ID: 738 - Posted: 10.20.2001