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Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than ' million visitors each month.


WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a new Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!



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Pregnancy Timeline by SemestersFemale Reproductive SystemFertilizationThe Appearance of SomitesFirst TrimesterSecond TrimesterThird TrimesterFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
 
December 9, 2011--------News Archive

Steroid Increases Life Expectancy for Preemies
Giving antenatal corticosteroids to moms expecting preterm infants - between 22 and 25 weeks gestation - reduces infant death and long-term impairment.

A New Understanding of How Our Lungs Grow
New research challenges the medical textbooks and declares that the tiny airsacs continue to increase in number as we grow to adulthood.

Early Pregnancy Stress, Pre-Term Birth, Fewer Boys
Stress in the second and third months of pregnancy can shorten pregnancies, increase the risk of pre-term births and lead to a decline in male babies.

December 8, 2011--------News Archive

Mother's Touch Protects Child Against Drug Cravings
Attentive, nurturing mothering may help her children better resist the temptations of drug use later in life.

Flu Vaccine Protects Pregnant Mom and New-Borns
The influenza shot boosts the immune response in pregnant women and protects neuronatal babies via antibodies transferred through the placenta.

Tadpoles Made to Grow Eyes on Back and Tail
Changing the voltage in embryonic frog cell of tadpole's back causes cell to develop into a functioning eye.

December 7, 2011--------News Archive

Baby See, Baby Do?
Study shows infants take cues from trusted sources only, and ignore unreliable faces.

Bitter Taste of Broccoli Not Just About Flavor
Broccoli’s taste is not just a matter of having a cultured palate; some people actually taste a bitter compound in the vegetable that others cannot.

Game Players Advance Genetic Research
Users of the game Phylo, designed by McGill University researchers, are contributing to analysis of DNA sequences in Alzheimer’s, diabetes and cancer.

December 6, 2011--------News Archive

One Quarter of Families Begin Before 24 Years Old
National Longitudinal Survey of Youth 1997, looked at the different paths to family formation. Results looks at the experiences of young adults through age 25.

Orphans Undergo Biological Change to Their Genome
Changes can be seen in the genetic regulation of the immune system, including a number of important mechanisms in the development and function of the brain.

Child Abuse Changes the Brain
Brain imaging reveals the same pattern of brain activity in these children as seen in soldiers in war.

December 5, 2011--------News Archive

Defect in Brain May Cause Autism-Like Syndrome
Autism in Timothy Syndrome has been found to produce fewer cells connecting both halves of the brain, and overproduce dopamine and norepinephrine.

Flipping Off the Switch that Causes Aging
For the first time, Harvard scientists have partially reversed age-related degeneration in mice, resulting in new growth of the brain and testes, improved fertility, and the return of lost cognitive function.

Mapping the Neurons Created in Youth
Harvard study of brain development may shed light on brain disorders such as autism and schizophrenia.

WHO Child Growth Charts


Researchers testing PTC sensitivity among the Yaaku people in Kenya


A team of University of Pennsylvania researchers has helped uncover the evolutionary history of one of the genes responsible for broccoli's bitterness. Beyond showing the ancient origins of the gene, the researchers discovered something unexpected: something other than taste must have driven its evolution.

Their research was published in the journal Molecular Biology and Evolution.

The researchers were interested in the gene TAS2R38, which codes for a bitter taste receptor protein of the same name. People with a certain version of that gene can taste phenylthiocarbamide, or PTC, which is chemically similar to naturally occurring bitter compounds, called glucosinolates, present in many foods, including cruciferous vegetables like broccoli and Brussels sprouts. These “tasters” find such foods to have a bitter taste that people with a different version can’t detect. As a result, “nontasters” have been shown to consume fewer cruciferous vegetables.

Modern humans originated in Africa, and populations from that region have the highest levels of genetic diversity globally. Previous studies had looked at variations in the PTC-sensitivity gene, but none had ever studied a large sample of diverse African populations with different cultures, ethnicities or diets.

“Because there is more genetic variation in African populations, you’re likely to see unique variants you may not see elsewhere,” Tishkoff said. “Our study of variation at the TAS2R38 gene in Africa and correlations with taste perception and diet gives us a clue about the evolutionary history of the gene and how natural selection might be influencing the pattern of variation.”

Genes that influence perception are of particular interest to geneticists because those genes are under strong evolutionary pressure; organisms with senses that are well adapted to their environment have better chances to survive and reproduce. PTC-sensitivity’s potential impact on nutrition, or the ability to detect bitter-tasting toxins, would therefore make it an obvious target for natural selection.

By looking at the TAS2R38 gene in 611 Africans from 57 diverse ethnic populations with distinct diets (for example, Pygmy hunter-gatherers and Maasai pastoralists), as well as in 132 non-Africans, the researchers showed that Africans had more variation than non-Africans, including several never-before-seen rare mutations.

The researchers also tested the correlation between genetic variation at this gene and levels of PTC tasting ability in 463 Africans, another first-of-its-kind study. In an experiment that was challenging to carry out across a wide swath of the African continent, participants sampled successively concentrated solutions of PTC and water until they were able to detect the bitter taste. When correlated with the participants’ genetic data, the study revealed that Africans have a broader range of PTC taste sensitivity than typically seen outside of Africa, and that relatively new rare mutations also decrease an individual’s ability to taste PTC.

Comparing different African populations confirmed that the PTC-sensitivity gene is millions of years old, meaning it predates the evolution of modern humans and likely existed in the common ancestor of modern humans and Neanderthals.

The study also revealed something surprising: local diet did not have an effect on the evolution of any of the PTC-sensitivity gene variants.

“Although we typically see a lot of genetic variation among diverse African populations, the frequency of TAS2R38 variants is fairly similar across different ethnicities, cultures and diets,” Campbell said. “This is suggestive that variation at this gene serves some other function beyond oral sensory perception.”

This counter-intuitive discovery is in line with other recent studies, which found receptors similar to TAS2R38 in the lungs, upper airways and gut. If the variations of the TAS2R38 gene have had a heretofore-undiscovered impact on breathing or digesting, alongside tasting, the former traits might be the true focus of natural selection.

“Why are we ‘tasting’ in our guts or in our lungs? There must be something else,” Tishkoff said, “that these taste receptors are doing, and it must be a pretty important physiological process, otherwise these variants wouldn’t be maintained.”

“We now believe the chemical senses play key sentinel roles at points of entry to the body like the mouth, airways and gastro-intestinal tract,” Breslin said. “It is possible that, in addition to detecting bitter-tasting thyroid toxins, products of this gene help to defend against ubiquitous pan-African threats, such as inhaling injurious compounds or growing undesirable bacteria in airway mucus or intestines.”

The team was led by Penn researchers Sarah Tishkoff, a Penn Integrates Knowledge professor with appointments in the genetics department in Penn’s Perelman School of Medicine and the biology department in the School of Arts and Sciences, and Michael C. Campbell, a postdoctoral fellow in the genetics department at the medical school, and included undergraduate and postdoctoral researchers from both the genetics and biology departments. The team included their collaborator Paul Breslin from the Monell Chemical Senses Center in Philadelphia and Rutgers University and researchers from the Musée de L’Homme in France, the National Institutes of Health and several African universities and research institutes.

In addition to Tishkoff and Campbell, the research was conducted by postdoctoral fellows Alessia Ranciaro and Jibril B. Hirbo, both of the genetics department in Penn’s Perelman School of Medicine; undergraduate student Daniel Zinshteyn of the biology department in the School of Arts and Sciences; Breslin; Alain Froment of the Musée de L’Homme; Sabah Omar of Kenya Medical Research Institute; Jean-Marie Bodo of Cameroon’s Ministry of Scientific Research and Innovation; Thomas Nyambo and Godfrey Lema of Tanzania’s Muhimbili University of Health and Allied Sciences; and Dennis Drayna of the NIH’s National Institute on Deafness and Other Communication Disorders.

The research was supported by the National Science Foundation, the National Institutes of Health and a David and Lucile Packard Career Award.

Original article: http://www.upenn.edu/pennnews/news/penn-geneticists-help-show-bitter-taste-perception-not-just-about-flavors