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A Common Herbicide Disrupts Human Hormonal Signaling
San Francisco, CA, USA. Atrazine, a common weedkiller in the U.S., already suspected of causing sexual abnormalities in frogs and fish, has now been found to alter hormonal signaling in human cells. The herbicide is the second most widely used weedkiller in the U.S., applied to corn and sorghum fields throughout the Midwest and also spread on suburban lawns and gardens. It was banned in Europe after studies linked the chemical to endocrine disruptions in fish and amphibians.
The University of California San Francisco (UCSF) (http://www.ucsf.edu/) study is the first to identify the full effect of atrazine on human cells. In studies with human placental cells in culture, the UCSF (http://www.ucsf.edu/) scientists found that atrazine increased the activity of a gene associated with abnormal human birth weight when over-expressed in the placenta. It also targeted a second gene that has been found to be amplified in the uterus of women with unexplained infertility. The findings were published in the journal Download PDF (http://ts-si.org/files/journal.pone.0002117.pdf) ]
In parallel studies of zebrafish, a widely used animal in development studies, the research team showed that atrazine feminized the fish population — increasing the proportion of fish that developed into females. In water with atrazine concentrations comparable to those found in runoff from agricultural fields, the proportion of female fish increased two-fold. Environmental factors are known to influence the sex of zebrafish and many other fish and amphibians as they develop.
These fish are very sensitive to endocrine disrupting chemicals, so one might think of them as 'sentinels' to potential developmental dangers in humans, said Holly Ingraham, PhD, senior author on the study and a UCSF Professor of Cellular and Molecular Pharmacology. These atrazine- sensitive genes are central to normal reproduction and are found in steroid producing...
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In The News: Olympic Relay Race? My Money Is On China.
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The Persistence Of Traumatic Life Events As Emotional Memories
Zurich, Switzerland. Post-traumatic Stress Disorder (PTSD) has returned to public awareness. This typically occurs when people experience extreme situations, such as accidents, natural catastrophes, serious illnesses, war, or other singular events. Our brain stores both positive and negative emotional memories, whether copnnected to traumatic life events or not, in a particularly robust manner. Consequently, the retention of such memories can have a very large effect on our behavior.
In the case of adverse memories, retention can place considerable restrictions on the way we go about our lives. As a result, we may avoid places, smells or objects that remind us of the traumatic experience, because they may trigger severe anxieties.
Control of the establishment of aversive memory by calcineurin and Zif268. Karsten Baumgärte, David Genoux, Hans Welz, Ry Y Tweedie-Cullen, Kyoko Koshibu, Magdalena Livingstone-Zatchej, Céline Mamie Isabelle M Mansuy. Nature Neuroscience 11(5):572-8. doi: 10.1038 / nn.2113
Researchers have now successfully tracked down the molecular bases of these strong, very persistent memories, showing that the enzyme calcineurin and the gene regulation factor Zif268 decisively determine the intensity of emotional memories.
The work was done by Isabelle Mansuy, Professor of Cellular Neurobiology at ETH Zurich (http://www.ethz.ch/index_EN) and of Molecular and Cognitive Neurosciences at the University of Zurich (http://www.unizh.ch/), and her research group. Their findings demonstrate for the first time a linkage between the regulatory processes at the synapse, which are important for emotional memories, and processes in the cell nucleus.
Mice as an ideal model system
The generation of very persistent memories in the shortest possible time needs molecules in the brain that are not only activated rapidly but which also efficiently control the signalling pathways of long-term information storage in the brain. This is why the protein phosphatase calcineurin, which was already known to...
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Jumping The Shark With the American Psychiatric Association
Washington, DC, USA. More than 120 researchers and clinicians with expertise in neuroscience, biology, genetics, statistics, epidemiology, public health, nursing, pediatrics and social work will form the work groups who will review scientific advances and research based information to develop the fifth edition of the APA Diagnostic and Statistical Manual of Mental Disorders (DSM-V) (http://en.wikipedia.org/wiki/Diagnostic_and_Statistical_Manual_of_Mental_Disorders). So who did we get to chair the workgroup on sexual and gender identity disorders (GID) ???
Here come Kenneth J. Zucker and Ray Blanchard, two Ph.D’s who, despite the ongoing research in neurobiology, believe that Harry Benjamin Syndrome (fna GID/transsexuality) is a psychological problem (not a biological condition), one that can be treated with drugs and $150 an hour therapy talks. [cf. Download of the APA News Release below.]
Kenneth J. Zucker, Ph.D., from Toronto's Centre for Addictions and Mental Health (CAMH) (http://www.camh.net/) believes in the unproven efficacy of reparative (e.g., ex-gay ) therapy to cure gender-variant children. Ray Blanchard, Ph.D. Professor, Department of Psychiatry, University of Toronto (http://www.utoronto.ca/) has published scientifically unsound research purporting that HBS women are autogynephilic (that is, paraphilic fetishists who are
sexually aroused by the thought or image of themselves as women).
Unable to make HBS men and women see the benefits of having bodies that are incongruent with their brains, Zucker proposes that he can cure them of the “delusion” they have had since birth. Ray Blanchard, a man who is unable to understand why someone would not want a penis, attests that HBS women (male to female), like Narcissus, obsess over their reflected image, imagining themselves with a vagina and breasts rather than a penis like Ray has.
Clinicians are inclined to diagnose disorders that they feel more comfortable treating. If Zucker is uncomfortable with a male to female HBS woman...
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There Are At Least Fourteen Ways This Could Go Badly
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TS Policy Review 
