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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 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


Changing the bioelectric voltage in an embryonic frog cell in this tadpole's back caused the cell to develop into a functioning eye. Image: Michael Levin/Sherry Aw



For the first time, scientists have altered natural bioelectrical communication among cells to directly specify the type of new organ to be created at a particular location within a vertebrate organism. Using genetic manipulation of membrane voltage in Xenopus (frog) embryos, biologists at Tufts University's School of Arts and Sciences were able to cause tadpoles to grow eyes outside of the head area.

The researchers achieved most surprising results when they manipulated membrane voltage of cells in the tadpole's back and tail, well outside of where the eyes could normally form. "The hypothesis is that for every structure in the body there is a specific membrane voltage range that drives organogenesis," said Pai. "These were cells in regions that were never thought to be able to form eyes. This suggests that cells from anywhere in the body can be driven to form an eye."

To do this, they changed the voltage gradient of cells in the tadpoles' back and tail to match that of normal eye cells. The eye-specific gradient drove the cells in the back and tail—which would normally develop into other organs—to develop into eyes.

These findings break new ground in the field of biomedicine because they identify an entirely new control mechanism that can be capitalized upon to induce the formation of complex organs for transplantation or regenerative medicine applications, according to Michael Levin, Ph.D., professor of biology and director of the Center for Regenerative and Developmental Biology at Tufts University's School of Arts and Sciences. Levin is senior and corresponding author on the work published in the journal Development online December 7 2011, in advance of print.

"These results reveal a new regulator of eye formation during development, and suggest novel approaches for the detection and repair of birth defects affecting the visual system," he said. "Aside from the regenerative medicine applications of this new technique for eyes, this is a first step to cracking the bioelectric code."

Tufts post-doctoral fellow Vaibhav P. Pai Ph.D., is first author of the paper, entitled "Transmembrane Voltage Potential Controls Embryonic Eye Patterning in Xenopus laevis."

From the outset of their research, the Tufts' biologists wanted to understand how cells use natural electrical signals to communicate in their task of creating and placing body organs. In recent research, Tufts biologist Dany S. Adams showed that bioelectrical signals are necessary for normal face formation in the Xenopus (frog) embryos. In the current set of experiments, the Levin lab identified and marked hyperpolarized (more negatively charged) cell clusters located in the head region of the frog embryo.

They found that these cells expressed genes that are involved in building the eye called Eye Field Transcription Factors (EFTFs). Sectioning of the embryo through the developed eye and analyzing the eye regions under fluorescence microscopy showed that the hyperpolarized cells contributed to development of the lens and retina. The researchers hypothesized that these cells turned on genes that are necessary for building the eye.

Next, the researchers were able to show that changing the bioelectric code, or depolarizing these cells, affected normal eye formation. They injected the cells with mRNA encoding ion channels, which are a class of gating proteins embedded in the membranes of the cell. Like gates, each ion channel protein selectively allows a charged particle to pass in and out of the cell.

Using individual ion channels that allow, the researchers changed the membrane potential of these cells. This affected expression of EFTF genes, causing abnormalities to occur: Tadpoles from these experiments were normal except that they had deformed or no eyes at all.

Further, the Tufts biologists were also able to show that they could control the incidence of abnormal eyes by manipulating the voltage gradient in the embryo. Pai: "Abnormalities were proportional to the extent of disruptive depolarization. We developed techniques to raise or lower voltage potential to control gene expression."

The researchers achieved most surprising results when they manipulated membrane voltage of cells in the tadpole's back and tail, well outside of where the eyes could normally form.

"The hypothesis is that for every structure in the body there is a specific membrane voltage range that drives organogenesis," said Pai. "By using a specific membrane voltage, we were able to generate normal eyes in regions that were never thought to be able to form eyes. This suggests that cells from anywhere in the body can be driven to form an eye."

Levin and his colleagues are pursuing further research, additionally targeting the brain, spinal cord, and limbs. The findings, he said "will allow us to have much better control of tissue and organ pattern formation in general. We are developing new applications of molecular bioelectricity in limb regeneration, brain repair, and synthetic biology." Additional authors include post-doctoral fellow Sherry Aw, Tufts Postdoctoral Associate Tal Shomrat, and Research Associate Joan M. Lemire. Funding for this research came from the National Institutes of Health.

"Transmembrane voltage potential controls embryonic eye patterning in Xenopus laevis," Vaibhav P. Pai, Sherry Aw, Tal Shormat, Joan M. Lemire, Development, published online before print December 20, 2011,doi:10.1242/dev.073759

Tufts University, located on three Massachusetts campuses in Boston, Medford/Somerville, and Grafton, and in Talloires, France, is recognized among the premier research universities in the United States. Tufts enjoys a global reputation for academic excellence and for the preparation of students as leaders in a wide range of professions. A growing number of innovative teaching and research initiatives span all Tufts campuses, and collaboration among the faculty and students in the undergraduate, graduate, and professional programs across the university's schools is widely encouraged.

Original article: http://www.eurekalert.org/pub_releases/2011-12/tu-rdt120711.php