Archive for the ‘University of Toronto’ Category

A placenta sustained you and every person ever born for 9 months, serving as your lungs and kidneys and pumping out hormones while you developed in the womb. Problems with this disk-shaped mass of tissue can contribute to everything from preterm births to diseases of middle age. Yet when a baby is born, hospitals usually throw the placenta away.

“It’s the least understood human organ,” says Alan Guttmacher, director of the National Institute of Child Health and Human Development (NICHD) in Bethesda, Maryland. “A large part of the scientific community never thinks about the placenta at all.” He and others hope to change that, however, by rallying researchers and funders, including other parts of the National Institutes of Health (NIH), around an effort to better understand the underappreciated organ. At an NICHD-sponsored workshop last week, some 70 researchers laid out their ideas for what NICHD calls the Human Placenta Project, including ways to better monitor the placenta during a pregnancy, and drugs to bolster it when it falters.

The human placenta forms primarily from cells that develop from the outer layer of fetal cells that surround an early embryo. Early in pregnancy, these trophoblasts invade the uterine wall and later develop a complex network of tiny projections called villi, which contain fetal blood vessels. This treelike structure of villi absorbs oxygen and nutrients from maternal blood; fetal waste and carbon dioxide meanwhile diffuse into the maternal bloodstream. Other specialized cells link the developing placenta to the umbilical cord. To avoid rejection by the mother’s immune system, the placenta employs various tricks, such as not expressing certain proteins. The placenta’s role during pregnancy is “an incredibly interesting biological time” that offers lessons for everything from cancer to organ transplantation, says physician-scientist Kimberly Leslie of the University of Iowa in Iowa City.

A malfunctioning, too small, or weakly attached placenta can starve the fetus, stunting its growth, and can also contribute to preeclampsia, or pregnancy-related high blood pressure, a condition that occurs in up to 6% of pregnancies and can require premature delivery of a baby. Adult diseases, too, ranging from cardiovascular disease to insulin resistance, seem to be linked to abnormal placenta morphology for poorly understood reasons.

During recent strategic planning at NICHD, researchers concluded that the placenta deserved closer study. “It came up repeatedly,” Guttmacher says. He expects that the Human Placenta Project will focus on understanding both the normal and abnormal placenta in real time during the course of pregnancy. It will also look for possible interventions—for example, a drug that would spur the growth of an abnormally small placenta.

Some at the workshop hope to adapt ultrasound and magnetic resonance imaging techniques now used to study the heart and brain to measure blood flow and oxygenation in the placenta. Injecting tracers, however, may be sensitive ethical territory. “People are very scared of doing things to pregnant women,” said placenta researcher Nicholas Illsley, of Hackensack University Medical Center in New Jersey, at the meeting. Another idea is to probe the mother’s bloodstream for cells and nucleic acids shed by the placenta as a window into the function of the organ.

Researchers also mused about creating a “placenta on a chip” that would mimic the tissue in the lab or developing molecular sensors that could monitor the placenta throughout pregnancy. “This sounds like science fiction, but if you showed me an iPhone 20 years ago, I would have said this was science fiction,” said Yoel Sadovsky, of the Magee-Womens Research Institute in Pittsburgh, Pennsylvania, at the meeting.

Attendees described a few immediate goals. One is to come up with standard definitions of a normal and abnormal placenta. Placenta morphology varies widely, and those from a healthy pregnancy can still have visible abnormalities, whereas those from sick babies often look completely normal, says systems biologist Brian Cox of the University of Toronto in Canada. Even before the NICHD meeting, the international community of placenta researchers had begun to coordinate their efforts by planning a website that will list existing placenta biobanks and help match collaborators.

At a time when NICHD’s budget is flat, money could be a limiting factor for the Human Placenta Project, which Guttmacher hopes will fund its first grants in 2016 and go for a decade or more. He expects that in addition to setting aside new money for the project, NICHD may give extra weight to high-quality grant applications focusing on the placenta. NICHD’s own contribution may be only “in the millions” of dollars, Guttmacher says. But he says eight other NIH institutes have expressed interest in contributing, as has the March of Dimes, an organization long focused on maternal and infant health. At long last, a throwaway organ may get the attention it deserves.

Thanks to Kebmodee for bringing this to the attention of the It’s Interesting community.

http://news.sciencemag.org/biology/2014/06/nih-gears-closer-look-human-placenta

Pedophiles’ brains are “abnormally tuned” to find young children attractive, according to a new study published this week. The research, led by Jorge Ponseti at Germany’s University of Kiel, means that it may be possible to diagnose pedophiles in the future before they are able to offend.

The findings, published in scientific journal Biology Letters, discovered that pedophiles have the same neurological reaction to images of those they find attractive as those of people with ordinary sexual predilections, but that all the relevant cerebral areas become engaged when they see children, as opposed to fellow adults. The occipital areas, prefrontal cortex, putamen, and nucleus caudatus become engaged whenever a person finds another attractive, but the subject of this desire is inverted for pedophiles.

While studies into the cognitive wiring of sex offenders have long been a source of debate, this latest research offers some fairly conclusive proof that there is a neural pattern behind their behavior.

The paper explains: “The human brain contains networks that are tuned to face processing, and these networks appear to activate different processing streams of the reproductive domain selectively: nurturing processing in the case of child faces and sexual processing in the case of sexually preferred adult faces. This implies that the brain extracts age-related face cues of the preferred sex that inform appropriate response selection in the reproductive domains: nurturing in the case of child faces and mating in the case of adult faces.”

Usually children’s faces elicit feelings of caregiving from both sexes, whereas those of adults provide stimuli in choosing a mate. But among pedophiles, this trend is skewed, with sexual, as opposed to nurturing, emotions burgeoning.

The study analyzed the MRI scans of 56 male participants, a group that included 13 homosexual pedophiles and 11 heterosexual pedophiles, exposing them to “high arousing” images of men, women, boys, and girls. Participants then ranked each photo for attractiveness, leading researchers to their conclusion that the brain network of pedophiles is activated by sexual immaturity.

The critical new finding is that face processing is also tuned to face cues revealing the developmental stage that is sexually preferred,” the paper reads.

Dr. James Cantor, associate professor at the University of Toronto’s Faculty of Medicine, said he was “delighted” by the study’s results. “I have previously described pedophilia as a ‘cross-wiring’ of sexual and nurturing instincts, and this data neatly verifies that interpretation.”

Cantor has undertaken extensive research into the area, previously finding that pedophiles are more likely to be left-handed, 2.3 cm shorter than the average male, and 10 to 15 IQ points lower than the norm.

He continued: “This [new] study is definitely a step in the right direction, and I hope other researchers repeat this kind of work. There still exist many contradictions among scientists’ observations, especially in identifying exactly which areas of the brain are the most central to pedophilia. Because financial support for these kinds of studies is quite small, these studies have been quite small, permitting them to achieve only incremental progress. Truly definitive studies about what in the brain causes pedophilia, what might detect it, and what might prevent it require much more significant support.”

Ponseti said that he hoped to investigate this area further by examining whether findings could be emulated when images of children’s faces are the sole ones used. This could lead to gauging a person’s predisposition to pedophilia far more simply than any means currently in place. “We could start to look at the onset of pedophilia, which is probably in puberty at about 12 or 14 years [old],” he told The Independent.

While Cantor is correct in citing the less than abundant size of the study, the research is certainly significant in providing scope for future practicable testing that could reduce the number of pedophilic crimes committed. By being able to run these tests and examine a person’s tendency toward being sexually attracted to underage children, rehabilitative care and necessary precautions could be taken to safeguard children and ensure that those at risk of committing a crime of this ilk would not be able to do so.

http://www.thedailybeast.com/articles/2014/05/23/study-finds-pedophiles-brains-wired-to-find-children-attractive.html#

On “I Hate Cilantro” websites and Facebook pages they gripe that the herb tastes like soap, mold, or dirt. Cilantro haters not only despise its flavor, they also detest its smell. Stories in publications as serious as the New York Times, the Wall Street Journal and, yes, even msnbc.com have even covered the sharp divide in taste preferences when it comes to this particular herb.  And when a study of identical twins found an aversion to cilantro stems from a genetic glitch, the herb’s bashers finally had a good reason why they found the leaves of the Coriander plant so offensive.

But who are these people in the anti-cilantro community? No one had a clue — until now.

There has been no attempt to quantify which people hate the herb until two nutrition experts from the University of Toronto took a stab at it. They recently published their findings in the journal Flavour. In the study, they surveyed nearly 1,400 young adults ages 20 to 29 in Canada.

Volunteers completed a 63-item preference checklist in which they rated each food on a 9-point scale from 1 (dislike extremely) to 9 (like extremely). They could also select “never tried” or “would not try.”

Researchers found an aversion to cilantro ranged from a low of 3 percent to a high of 21 percent among six different ethnic groups.

Young Canadians with East Asian roots, which included those of Chinese, Japanese, Korean, Thai and Vietnamese descent, had the highest prevalence of people who disliked the herb at 21 percent. Caucasians were second at 17 percent, and people of African descent were third at 14 percent.

Among the herb’s fans, the group with the fewest number of people who disliked cilantro were those of Middle Eastern background at 3 percent, followed by those of Hispanic and South Asian ancestry at 4 percent and 7 percent respectively.

Exposure to the herb at an earlier age and with greater frequency in Mexican, Asian, and Indian cooking likely helps shape a positive flavor preference. Another possibility is that genetic differences among the cultural groups might influence someone’s taste perception of the herb.

Although researchers have yet to evaluate all 63 items on the food-preference checklist, study author Ahmed El-Sohemy, PhD, is sure of one thing: “Cilantro is perhaps the most polarizing with large numbers either loving it or hating it.” The paper calls this the “unusual divisive nature of cilantro.”

“People who dislike cilantro extremely describe it very, very differently from those who love it,” explains El-Sohemy, an associate professor of nutrition at the University of Toronto. The reason? “These individuals live in very different sensory worlds and are not perceiving the same thing,” he says.

As for El-Sohemy’s opinion of cilantro, count him among the lovers. “I remember loving the taste as a child,” he says. “I distinctly remember my mother’s Egyptian cooking, which used cilantro frequently.”

The study is a first step in determining how widespread a dislike for cilantro is, at least in a sample of young Canadians. It’s unclear whether older Canadians feel similarly or how much the herb is despised by people in other countries.

Eventually, the Toronto scientists hope to pinpoint the genetic basis for why cilantro is an herb some people love to hate.

http://bodyodd.nbcnews.com/_news/2012/05/16/11719087-who-hates-cilantro-study-aims-to-find-out

Thanks to Dr. S.G. for bringing this to the attention of the It’s Interesting community.