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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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November 4, 2011--------News Archive

Identifying Brain Cells That Keep Us Awake
Researchers at UCLA have identified the group of neurons that mediates whether light arouses us — or not.

TBL1X Gene Involved In Autism Spectrum Disorder
An X-chromosome-wide association study in autism families identifies TBL1X as a novel autism spectrum disorder candidate gene in males.

“Love Hormone” Helps Direct Development of Brain
Hormones released from nerves regulate a series of vital body processes, including the balance of fluids and uterine contractions in childbirth.

November 3, 2011--------News Archive

Steroids in Preemies Impair Brain Growth
Premature infants given drugs to support lung maturation and normalize blood pressure, are at increased risk for having impaired growth of the cerebellum.

Potential Treatment for Sickle Cell Disease
Increasing the expression of proteins TR2/TR4 can lead to higher fetal hemoglobin levels in sickle cell patients.

New Drug Shows Promise Against Multiple Sclerosis
A new drug targets a molecule - CD20 found on the surface of B cells and B cells seem to induce the immune system T cells to attack.

November 2, 2011--------News Archive

Babies Understand Each Other at Ten Months Old
At 10 months, babies start to understand another person’s thought process, providing new insights on how communication develops.

Bacteria Swap Genes Between Species Readily
Microbes have developed a quick and effective way to exchange genetic information coding for antibiotic resistance, other functions.

Pinpointing Cause of Unexplained Miscarriage
The same kind of blood-clotting in coronary arteries or blood vessels in the brain which causes heart attacks and strokes also happens in the placenta.

November 1, 2011--------News Archive

Pregnant Mothers At Risk From Air Pollution
A Californian-based study has looked in detail at air quality and the impact of traffic-related air pollution on premature birth.

Linking A Spectrum of Childhood Diseases
An international collaboration of scientists has identified a genetic mutation causing a rare childhood disease characterized by inflammation and fat loss.

Placenta and Uterus Battle Becomes Preeclampsia
A battle brews in the mother’s womb between the father’s biological goal to produce the biggest, healthiest baby possible vs. the mother’s need to live through delivery.

October 31, 2011

Fetal Heart Rate Not a Good Indicator for Health
Maternal-fetal medicine specialists at Intermountain Medical Center seek better 'road map' to improve deliveries, healthier babies.

Swedish Discover Bisphenol-A Affects Newborn Brain
An observed effect induced in neonatal baby mice after exposure to Bisphenol A, persisted into adulthood.

Not Your Mother's Birth Control
Today's hormonal forms of birth control are vastly different from those used by earlier generations of women, both with lower levels of hormones and with different means of delivery (not just a pill), but many of the same problems related to women's pleasure remain.

WHO Child Growth Charts



Much as people can exchange information instantaneously in the digital age, bacteria associated with humans and their livestock appear to freely and rapidly exchange genetic material related to human disease and antibiotic resistance through a mechanism called horizontal gene transfer (HGT).

In a paper appearing in Nature online Oct. 30, researchers — led by Eric Alm of MIT's Department of Civil and Environmental Engineering and Department of Biological Engineering — say they've found evidence of a massive network of recent gene exchange connecting bacteria from around the world: 10,000 unique genes flowing via HGT among 2,235 bacterial genomes.

HGT is an ancient method for bacteria from different lineages to acquire and share useful genetic information they didn't inherit from their parents. Scientists have long known about HGT and known that when a transferred gene confers a desirable trait, such as antibiotic resistance or pathogenicity, that gene may undergo positive selection and be passed on to a bacterium's own progeny, sometimes to the detriment of humans. (For example, the proliferation of antibiotic-resistant strains of bacteria is a very real threat, as seen in the rise of so-called "superbugs.")

But until now, scientists didn't know just how much of this information was being exchanged, or how rapidly. The MIT team's work illustrates the vast scale and rapid speed with which genes can proliferate across bacterial lineages.

"We are finding [completely] identical genes in bacteria that are as divergent from each other as a human is to a yeast," says Alm, the Karl Van Tassel Associate Professor. "This shows that the transfer is recent; the gene hasn't had time to mutate."

"We were surprised to find that 60 percent of transfers among human-associated bacteria include a gene for antibiotic resistance," adds computational systems biology graduate student Chris Smillie, one of the lead authors of the paper.

These resistance genes might be linked to the use of antibiotics in industrial agriculture: The researchers found 42 antibiotic-resistance genes that were shared between livestock-associated and human-associated bacteria, demonstrating a crucial link connecting pools of drug resistance in human and agricultural populations.

"Somehow, even though a billion years of genome evolution separate a bacterium living on a cow and a bacterium living on a human, both are accessing the same gene library," Alm says. "It's powerful circumstantial evidence that genes are being transferred between food animals and humans."

Moreover, the team identified 43 independent cases of antibiotic-resistance genes crossing between nations.

"This is a real international problem," says microbiology graduate student Mark Smith, another lead author of the study. "Once a trait enters the human-associated gene pool, it spreads quickly without regard for national borders."

The practice of adding prophylactic antibiotics to animal feed to promote growth and prevent the spread of disease in densely housed herds and flocks is widespread in the United States, but has been banned in many European countries. According to the Federal Drug Administration, more than 80 percent of the 33 million pounds of antibiotics sold in the United States in 2009 was for agricultural use, and 90 percent of that was administered subtherapeutically through food and water. This includes antibiotics such as penicillins and tetracyclines commonly used to treat human illness.

The MIT researchers found that HGT occurs more frequently among bacteria that occupy the same body site, share the same oxygen tolerance or have the same pathogenicity, leading them to conclude that ecology — or environmental niche — is more important than either lineage or geographical proximity in determining if a transferred gene will be incorporated into a bacterium's DNA and passed on to its descendants.

"This gives us a rulebook for understanding the forces that govern gene exchange," Alm says.

The team applied these rules to find genes associated with the ability to cause meningitis and other diseases, with the hope that transferred traits and the genes encoding those traits might make especially promising targets for future drug therapies.

"This is a very interesting piece of work that really shows how the increasing databases of complete genome sequences, together with detailed environmental information, can be used to discover large-scale evolutionary patterns," says Rob Knight, associate professor of chemistry and biochemistry at the University of Colorado at Boulder, who says he agrees with the authors' findings. "The availability of vast datasets with excellent environmental characterization will give us an unprecedented view of microbes across the planet."

Continuing the work, the researchers are now comparing rates of exchange among bacteria living in separate sites on the same person and among bacteria living on or in people with the same disease. They're also studying an environmentally contaminated site to see which swapped genes might facilitate microbial cleanup by metal-reducing bacteria.

Other co-authors of the Nature paper are graduate student Jonathan Friedman, postdoc Otto Cordero and former graduate student Lawrence David, now at Harvard University.

The work is part of the National Institutes of Health's Human Microbiome Project. It was funded by the Department of Energy's ENIGMA Scientific Focus Area and the National Science Foundation.

Original article: http://web.mit.edu/newsoffice/2011/hgt-bacteria-1031.html