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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.


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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

Brain Defect 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


by Tanya Lewis

Neuroscientists at Stanford University School of Medicine have homed in on potential differences in autistic people’s brain cells by studying brainlike spheres grown in an elaborate process from skin cells.

The scientists studied cells from patients with Timothy syndrome, a rare genetic condition that is associated with one of the most penetrant forms of autism: In other words, most people with the Timothy syndrome mutation have autism as a symptom, among other problems.

Autism is a spectrum of developmental disorders of impaired social and verbal interaction. Currently, no medication exists to treat its underlying causes, according to the U.S. National Library of Medicine. Understanding what goes awry in autistic brain development could improve prospects for treating the condition.

In this study, the scientists suggest that the autism in Timothy syndrome patients is caused by a gene mutation that makes calcium channels in neuron membranes defective, interfering with how those neurons communicate and develop. The flow of calcium into neurons enables them to fire, and the way that the calcium flow is regulated is a pivotal factor in how our brains function.

The researchers also found brain cells grown from individuals with Timothy syndrome resulted in fewer of the kind of cells that connect both halves of the brain, as well as an overproduction of two of the brain’s chemical messengers, dopamine and norepinephrine. Furthermore, they found they could reverse these effects by chemically blocking the faulty channels.

Postdoctoral scholar Sergiu Pasca, MD, and Ricardo Dolmetsch, PhD, associate professor of neurobiology, led the study, published online Nov. 27 in Nature Medicine. Dolmetsch, a biophysicist, redirected his research to study autism after his son was diagnosed with autism. It’s unclear what leads to autism, but its incidence is increasing, he said.

The gaps in our understanding of the causes of psychiatric disorders such as autism have made them difficult to treat. Perhaps the biggest obstacle to research into autism and other psychiatric and neurological diseases is that scientists can’t get living brain cell samples from people with these conditions, for obvious reasons. Dolmetsch and his colleagues figured out a solution to this dilemma, using a novel approach involving what are known as induced pluripotent stem cells, or iPS cells.

“We developed a way of taking skin cells from humans with Timothy syndrome and converting them into stem cells, then converting those stem cells into neurons,” said Dolmetsch.

The scientists grew these iPS cells as free-floating clumps in a nutrient-rich solution, later transferring the clumps to tissue culture plates. Here, some of them formed three-dimensional, brainlike spheres whose cells later migrated outward and matured into neurons. These neurons formed three distinct layers, a good first approximation of living tissue in the brain. By visualizing these neurons under a microscope and quantifying their gene expression, the scientists were able to characterize at the cellular level abnormalities that may be associated with autism.

The neurons grown from Timothy-syndrome iPS cells showed larger-than-normal spikes in calcium levels, suggesting the calcium channels lost their ability to shut off. This set off dramatic changes in neuronal signaling, reconfiguring how genes were expressed.

The cerebral cortex, the outer layer of the brain, has six distinct layers. In Timothy syndrome cell cultures, the proportion of neurons of specific layers differed from that in normal brains — additional biological evidence for the disorder. The neurons grown from the Timothy syndrome cells were less characteristic of lower-level neurons, which include neurons that bridge the left and right halves of the brain via the bundle of fibers known as the corpus callosum. This reinforces the view that autism results from defects in brain connectivity.

Pasca and Dolmetsch had an “aha” moment when they realized the neurons grown from Timothy syndrome cells were making too much of the enzyme most critical for producing dopamine and norepinephrine, which play an important role in sensory processing and social behavior. The realization may offer important clues about what causes the problems seen in autism.

To determine whether the enzyme upsurge was reversible, the scientists treated the neurons with a chemical that blocks the defective calcium channels, called roscovitine. They saw a nearly 70 percent reduction in the proportion of cells producing the enzyme, confirming the defective calcium channel was the culprit in producing too much dopamine and norepinephrine. Such reversibility suggests that certain cellular abnormalities in autism may be treatable.

Dolmetsch warned, however, that roscovitine is not currently approved for use in humans and has never been tested in children. While it is currently in clinical trials for lung cancer, it reportedly causes nausea and other side effects.

“The reported side effects are probably due to the fact that, in addition to targeting the channel that is mutated in autism, roscovitine also inhibits kinases that are required for cell proliferation,” he said. “We think that roscovitine is a good starting point, but probably has to be optimized before it would be useful for autism.”

In the meantime, the study represents a major achievement with its success in developing a technique to recreate how the neurons of individuals with Timothy syndrome develop in a lab setting. It’s the first time it’s been possible to study the disorder in human cells rather than mouse cells, so it represents a better clinical model, Dolmetsch said.

“These results could lead to a very powerful research tool,” he said. “It’s human psychiatric disease in a petri dish.”

Researchers from UCLA contributed to the study. Other authors from Stanford were postdoctoral scholars Thomas Portmann, PhD, Masayuki Yazawa, PhD, and Oleksandr Shcheglovitov, PhD; clinical researcher Anca Pasca, MD; neurology researcher Branden Cord MD, PhD; associate professor of neurosurgery Theo Palmer, PhD; Sachiko Chikahisa, PhD, and research professor of psychiatry and behavioral sciences Nishino Seiji, MD, PhD, both of the Sleep and Circadian Neurobiology Laboratory; clinical assistant professor of medical genetics Jonathan Bernstein, MD, PhD; and associate professor of psychiatry and behavioral sciences Joachim Hallmayer, MD.

Financial support was provided by the National Institutes of Health, a Simons Foundation grant, International Brain Research Organization, the Tashia and John Morgridge Endowed Fellowship, Japan Society of the Promotion for Science, American Heart Association Western States, the Swiss National Science Foundation, the California Institute for Regenerative Medicine and several individual donors. Information about the Department of Neurobiology, in which the study was conducted, is available at http://neurobiology.stanford.edu/.

Tanya Lewis is a science-writing intern in the medical school's Office of Communication & Public Affairs.

Original article: http://med.stanford.edu/ism/2011/november/dolmetsch.html