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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
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December 2, 2011--------News Archive

Working Moms Multitask More Than Dads
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Unlocking the Genetic Mystery of Sarcomas
Study uncovers potential targets for treating a disease affecting children and adults.

When Babies Wake, Cortisol Rises to Mom's Level
The hormone cortisol in adults rises and lowers according to stress. But in babies cortisol remains level following waking - and tunes in with mom's level.

December 1, 2011--------News Archive

Home Births – Then and Now
A comparison of home-birth trends of the 1970s finds many similarities – and some differences – related to trends in home births today.

Risk of Suicide In Pregnant Women, New Mothers
An analysis of new data highlights risk factors that could be targeted by interventions.

Addiction Damages PreFrontal Cortex
Brain structure-function impairment may be related to an inability to assess rewards and consequences, behavior associated with addiction.

November 30, 2011--------News Archive

Gene Puts Brakes On Breast Cancer Progression
Newly published research explores the role of gene in tumour suppression

‘Perfect Parent’ Not A Good Idea
Seeking perfection as a parent works better for dads than for moms.

Kindergarten Friendships Matter, Especially for Boys
High-quality friendships in kindergarten may mean that boys will have fewer behavior problems and better social skills in first and third grades.

November 29, 2011--------News Archive

Cleft Lip Corrected Genetically in Mouse Model
Scientists have successfully genetically repaired cleft lips in mice embryos specially engineered for the study of cleft lip and cleft palate.

Common Herbicide Creates Reproductive Problems
International researchers link exposure to atrazine – an herbicide widely used in the U.S. and more than 60 other nations – to reproductive problems in animals.

Environment and Diet Leave Imprints On the Heart
DNA methylation in the human heart has revealed the 'missing link' between lifestyle and health, and may indicate methylation creates the equivalent of 5, 6, 7 and 8 bases by modifying Cytosines across our entire genome.

November 28, 2011--------News Archive

Role of Nuclear Membrane Protein in Organ Growthh
Scientists had thought B-type lamin proteins were vital to embryonic stem cells; but they are more critical to organ formation.

Hormone Hepcidin May Control Atherosclerosis
Hepcidin is a hormone produced by the liver and regulates iron transport. Blocking its production encourages macrophages to counter atherosclerosis.

Two Enzymes Stamp DNA with "Turn Off" Signal
Inside the cell nucleus, DNA is wound around spool-like proteins called histones. Two modifications in this attachment tell a portion of the DNA to be on or off.

WHO Child Growth Charts


Both of these African clawed frogs are genetically male, but lifelong exposure to the herbicide atrazine transformed the frog on the bottom to female. The frog reproduced with normal males twice. Photo by Tyrone Hayes

An international team of researchers has reviewed the evidence linking exposure to atrazine – an herbicide widely used in the U.S. and more than 60 other nations – to reproductive problems in animals. The team found consistent patterns of reproductive dysfunction in amphibians, fish, reptiles and mammals exposed to the chemical.

Atrazine is the second-most widely used herbicide in the U.S. More than 75 million pounds of it are applied to corn and other crops, and it is the most commonly detected pesticide contaminant of groundwater, surface water and rain in the U.S.

The new review, compiled by 22 scientists studying atrazine in North and South America, Europe and Japan, appears in the Journal of Steroid Biochemistry and Molecular Biology.

The researchers looked at studies linking atrazine exposure to abnormal androgen (male hormone) levels in fish, amphibians, reptiles and mammals and studies that found a common association between exposure to the herbicide and the “feminization” of male gonads in many animals.

The most robust findings are in amphibians, said University of Illinois comparative biosciences professor Val Beasley, a co-author of the review. At least 10 studies found that exposure to atrazine feminizes male frogs, sometimes to the point of sex reversal, he said.

Beasley’s lab was one of the first to find that male frogs exposed to atrazine in the wild were more likely to have both male and female gonadal tissue than frogs living in an atrazine-free environment. And in a 2010 study, Tyrone Hayes, a professor of integrative biology at the University of California at Berkeley and lead author of the review, reported in the Proceedings of the National Academy of Sciences that atrazine exposure in frogs was associated with “genetic males becoming females and functioning as females,” Beasley said.

“And this is not at extremely high concentrations,” he said. “These are at concentrations that are found in the environment.”

The new review describes the disruptions of hormone function and sexual development reported in studies of mammals, frogs, fish, reptiles and human cells exposed to the herbicide. The studies found that atrazine exposure can change the expression of genes involved in hormone signaling, interfere with metamorphosis, inhibit key enzymes that control estrogen and androgen production, skew the sex ratio of wild and laboratory animals (toward female) and otherwise disrupt the normal reproductive development and functioning of males and females.

“One of the things that became clear in writing this paper is that atrazine works through a number of different mechanisms,” Hayes said. “It’s been shown that it increases production of (the stress hormone) cortisol. It’s been shown that it inhibits key enzymes in steroid hormone production while increasing others. It’s been shown that it somehow prevents androgen from binding to its receptor.”

The review also consolidates the evidence that atrazine undermines immune function in a variety of animals, in part by increasing cortisol.
“Cortisol is a nonspecific response to chronic stress,” Beasley said. “But guess what? Wildlife in many of today’s habitats are stressed a great deal of the time. They’re stressed because they’re crowded into little remnant habitats. They’re stressed because there’s not enough oxygen in the water because there are not enough plants in the water (another consequence of herbicide use). They’re stressed because of other contaminants in the water. And the long-term release of cortisol causes them to be immuno-suppressed.”

There also are studies that show no effects – or different effects – in animals exposed to atrazine, Beasley said. “But the studies are not all the same. There are different species, different times of exposure, different stages of development and different strains within a species.” All in all, he said, the evidence that atrazine harms animals, particularly amphibians and other creatures that encounter it in the water, is compelling.

“I hope this will stimulate policymakers to look at the totality of the data and ask very broad questions,” Hayes said. “Do we want this stuff in our environment? Do we want – knowing what we know – our children to drink this stuff? I would think the answer would be no.”

Original article:http://news.illinois.edu/news/11/1128atrazine_ValBeasley.html