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New Study Shows Sexual Orientation Revealed by One's Eyes

A new study reveals that sexual orientation can be detected by looking at the pupils of our eyes.

EyeScience Daily reports:

For the first time, researchers at Cornell University used a specialized infrared lens to measure pupillary changes to participants watching erotic videos. Pupils were highly telling: they widened most to videos of people who participants found attractive, thereby revealing where they were on the sexual spectrum from heterosexual to homosexual.

The findings were published August 3 in the scientific journal PLoS ONE.

Previous research explored these mechanisms either by simply asking people about their sexuality, or by using physiological measures such as assessing their genital arousal. These methods, however, come with substantial problems.

"We wanted to find an alternative measure that would be an automatic indication of sexual orientation, but without being as invasive as previous measures. Pupillary responses are exactly that," says Gerulf Rieger, lead author and research fellow at Cornell. "With this new technology we are able to explore sexual orientation of people who would never participate in a study on genital arousal, such as people from traditional cultures. This will give us a much better understanding how sexuality is expressed across the planet."

Justin Lehmiller adds:

The idea for this study came out of past research indicating that our pupils naturally dilate when we see something interesting. This is an involuntary response activated by our autonomic nervous system, a bodily system that controls breathing, digestion, heart rate, and many other automatic processes. Pupil dilation is therefore something that it unlikely to be under a person’s conscious control. One previous study conducted in the 1960s found that people’s pupils tend to dilate when they see sexually arousing imagery, but that study only looked at a total of 10 participants (half heterosexual and half homosexual), all of whom were men.

In the new study, 325 men and women of varying sexualities (heterosexual, homosexual, and bisexual) watched a series of one-minute video clips in random order. The video content was either a man masturbating, a woman masturbating, or a neutral landscape. A gaze-tracking camera measured the size of participants’ pupils every two milliseconds as the videos were shown. All videos were of equivalent brightness to ensure that changes in light did not affect pupil size.


Report: Doctors Engineering Fetuses to Prevent Intersex, Tomboy, and Lesbian Children

The Journal of Bioethical Inquiry recently published a paper detailing an increasing amount of off-label medical intervention used by U.S. doctors to prenatally engineer fetuses with steroids in order to prevent intersex, tomboy, and lesbian babies, according to a Northwestern University report compiled largely with findings obtained from Freedom of Information Act requests:

WombThe pregnant women targeted are at risk for having a child born with the condition congenital adrenal hyperplasia (CAH), an endocrinological condition that can result in female fetuses being born with intersex or more male-typical genitals and brains. Women genetically identified as being at risk are given dexamethasone, a synthetic steroid, off-label starting as early as week five of the first trimester to try to “normalize” the development of those fetuses, which are female and CAH-affected. Because the drug must be administered before doctors can know if the fetus is female or CAH-affected, only one in eight of those exposed are the target type of fetus.

The off-label intervention does not prevent CAH; it aims only at sex normalization. Like Diethylstilbestrol (DES) -- which is now known to have caused major fertility problems and fatal cancers among those exposed in utero -- dexamethasone is a synthetic steroid. Dexamethasone is known -- and in this case intended -- to cross the placental barrier and change fetal development. Experts estimate the glucocorticoid dose reaching the fetus is 60 to 100 times what the body would normally experience.

According to Northwestern, the report provides evidence that proponents of the intervention are interested in reducing rates of "behavioral masculinization" and the NIH has funded experiments to this end.

There is "a nearly 20 percent 'serious adverse event' rate among the children exposed in utero." Mothers have been told that it is safe but there is no scientific evidence, and the FDA cannot prevent the procedure being advertised as safe because the advertising is done by "a clinician not affiliated with the drug maker."

90 percent of those exposed to the procedure cannot benefit, and medical societies have been saying this for a decade.

According to Northwestern, "The paper is authored by Alice Dreger, professor of clinical medical humanities and bioethics at Northwestern University Feinberg School of Medicine and is co-authored by Ellen Feder, associate professor of philosophy and religion at American University, and Anne Tamar-Mattis, executive director of Advocates for Informed Choice."


Scientists Create Artificial Jellyfish from Rat Cells: VIDEO

Scientists have built a synthetic jellyfish from silicone and cells from a rat's heart:

MedusoidThe synthetic creature, dubbed a medusoid, looks like a flower with eight petals. When placed in an electric field, it pulses and swims exactly like its living counterpart.

“Morphologically, we’ve built a jellyfish. Functionally, we’ve built a jellyfish. Genetically, this thing is a rat,” says Kit Parker, a biophysicist at Harvard University in Cambridge, Massachusetts, who led the work. The project is described today in Nature Biotechnology1.

Parker’s lab works on creating artificial models of human heart tissues for regenerating organs and testing drugs, and the team built the medusoid as a way of understanding the “fundamental laws of muscular pumps”.

The hope is to create something similar from human heart cells to test drugs that would improve cardio functions.

Watch it move, AFTER THE JUMP...

Continue reading "Scientists Create Artificial Jellyfish from Rat Cells: VIDEO" »


The Fight Against AIDS In Washington D.C.

Washington_hiv_0316

Today in Washington D.C., 20,000 soldiers in the fight against AIDS -- doctors, writers, social scientists, public policy experts, academicians, and more -- have gathered for the bi-annual meeting of the International AIDS Society. Perhaps because of the gathering, the New York Times has compiled a really excellent profile of the city's recent responses to the AIDS epidemic. It's very worth reading.

Washington D.C. hasn't always reacted well to AIDS, which may be why it's got one of the nation's highest per-capita infection rates. From the Times:

 “D.C. used to be a bureaucratic nightmare,” said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, which is just three subway stops outside the city, in Bethesda, Md. When Adrian M. Fenty took office as the mayor of Washington in 2007, Dr. Fauci said, “it was a whole new morning in America.”

The change is evident on many fronts ... The city gave away five million male and female condoms last year, 10 times as many as it did in 2007. More than 300,000 clean needles a year are given away, both to heroin users and to an even higher risk group: transgender prostitutes who inject hormones.        

What's more: D.C. now offers testing almost everywhere -- grocery stores, the DMV -- and, in some locations, people are paid seven bucks to get tested. Of the individuals who test positive, 89% see a doctor within three days -- in some cases, driven to the doctor's office by non-profit organizations hired by the government.

Though the city's good at getting newly diagnosed individuals to the doctor, it's struggling to maximize the effectiveness of tests to ensure that the most vulnerabe populations are served. From the Times:

[A] weak point is the inefficiency of random testing. Each test consumes about 20 minutes alone in a room with a counselor — and only about one of every 100 people tested at the Department of Motor Vehicles, for example, is infected. ... Even at AIDS clinics here, only 2 percent of tests are positive. Many family doctors resist testing at all.        

"Contact tracing" -- reaching out to a newly newly diagnosed individual's past sexual contacts -- is more effective, but those who have only just learned they're infected are often unable, or unwilling, to cooperate. Now Washington is experimenting with a less fraught way of reaching high-risk individuals: a ten-dollar cash incentive for those who convince high-risk friends and acquaintances to get tested.

All the effort seems to be having an effect. The Times reports that the number of Washingtonians getting tested each year for HIV has tripled since 2007 -- from 43,000 to 122,000. 

 


Doctors Testing Nicotine Vaccine That Could One Day Prevent Smoking

NicotinevaccineA team led by Dr. Ronald G. Crystal, chairman and professor of Genetic Medicine at Weill Cornell Medical College in the Big Apple, have tested a vaccine that protects the brain from nicotine.

CBS News reports:

Much like vaccines for diseases that create antibodies to fight infection, the vaccine creates antibodies against nicotine. However, previous attempts at similar vaccines have failed because within a few weeks the antibodies are gone, which won't exactly help people stay smoke-free.

Crystal's team developed a vaccine that contains a virus consisting of a genetic sequence they engineered from a nicotine antibody, and injected it into the liver of mice. The injection genetically modifies the liver to churn out nicotine antibodies, along with other cells it typically makes, thus providing a nicotine antibody "factory" in the body...

The antibodies then work by targeting the nicotine cells within seconds of exposure and preventing them from reaching receptors in the brain that provide the "chill out" feeling, as Crystal called it.

The vaccine, which Crystal says could be tested on humans within a few years, would most likely be a preventative measure. Using it while trying to quit would, in essence, be like quitting cold turkey, and who needs a shot for that?


A Brief Examination Of Homophobia In Medicine

DaVinciHeartThe latest edition of Academic Pediatrics reprints remarks Dr. Mark A. Schuster, head of general pediatrics at Boston Children's Hospital, made in 2010 about experiencing homophobia during medical school.

One story Schuster details in his remarks, delivered at the Children’s Hospital Boston GLBT & Friends Celebration, concerns a woman with symptoms of a herniated disc.

Though the surgeons were ready to operate, and the students ready to learn, a radiologist reversed his diagnosis because the woman appeared to be a lesbian, thus jeopardizing the woman's well-being.

The neurosurgeon abruptly canceled the operation. It turned out that the radiologist had reversed his reading. When pressed as to why he no longer saw what even a third-year medical student could see (that would be me), he confessed that the neurosurgeon had pressured him to change his read.

When our team met with the neurosurgeon, he was direct. He had seen what he assumed to be a lesbian novel at the patient’s bedside, and he wasn’t going to operate. His rationalization was that she might have inserted something into her urethra that caused her incontinence. He had no research or case studies to support his theory. He had no explanation for why a lesbian would do this. He had no explanation for why it wasn’t showing up on x-ray. He made it clear, though, that he wasn’t going to operate on a lesbian.

Dr. Pauline W. Chen at the New York Times says the reprinted Schuster speech "delivers unflinching, evenhanded descriptions of a profession that is committed to helping others, yet is also capable of treating some of its own as aberrant." Still, I would say being the patient in such a situation would be equally horrible, if not worse.

The woman in Schuster's story ended up getting the operation, for those who wondered. You can read more of his experience with this PDF.


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