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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

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


Research by Ronald A. DePinho (above), a Harvard Medical School professor of genetics, shows for the first time a dramatic reversal of many aspects of age-related degeneration in mice, a milestone in aging science achieved by engineering mice with a controllable telomerase gene. The projection of chromosomes seen here shows telomeres (highlighted in red) on their ends.

Harvard scientists at Dana-Farber Cancer Institute say they have for the first time partially reversed age-related degeneration in mice, resulting in new growth of the brain and testes, improved fertility, and the return of a lost cognitive function.

In a report posted online by the journal Nature in advance of print publication, researchers led by Ronald A. DePinho, a Harvard Medical School (HMS) professor of genetics, said they achieved the milestone in aging science by engineering mice with a controllable telomerase gene. The telomerase enzyme maintains the protective caps called telomeres that shield the ends of chromosomes.

As humans age, low levels of telomerase are associated with progressive erosion of telomeres, which may then contribute to tissue degeneration and functional decline in the elderly. By creating mice with a telomerase switch, the researchers were able to generate prematurely aged mice. The switch allowed the scientists to find out whether reactivating telomerase in the animals would restore telomeres and mitigate the signs and symptoms of aging. The work showed a dramatic reversal of many aspects of aging, including reversal of brain disease and infertility.

While human applications remain in the future, the strategy might one day be used to treat conditions such as rare genetic premature aging syndromes in which shortened telomeres play an important role, said DePinho, senior author of the report and the director of Dana-Farber’s Belfer Institute for Applied Cancer Science. “Whether this would impact on normal aging is a more difficult question,” he added. “But it is notable that telomere loss is associated with age-associated disorders and thus restoration of telomeres could alleviate such decline.” The first author is Mariela Jaskelioff, a research fellow in medicine in DePinho’s laboratory.

Importantly, the animals showed no signs of developing cancer. This remains a concern because cancer cells turn on telomerase to make themselves virtually immortal. DePinho said the risk can be minimized by switching on telomerase only for a matter of days or weeks — which may be brief enough to avoid fueling hidden cancers or cause new ones to develop. Still, he observed, it is an important issue for further study.

In addition, DePinho said these results may provide new avenues for regenerative medicine, because they suggest that quiescent adult stem cells in severely aged tissues remain viable and can be reactivated to repair tissue damage.

“If you can remove the underlying damage and stresses that drive the aging process and cause stem cells to go into growth arrest, you may be able to recruit them back into a regenerative response to rejuvenate tissues and maintain health in the aged,” he said. Those stresses include the shortening of telomeres over time that causes cells and tissues to fail.

Loss of telomeres sends a cascade of signals that cause cells to stop dividing or self-destruct, stem cells to go into retirement, organs to atrophy, and brain cells to die. Generally, the shortening of telomeres in normal tissues shows a steady decline, except in the case of cancer, where they are maintained.

The experiments used mice that had been engineered to develop severe DNA and tissue damage as a result of abnormal, premature aging. These animals had short, dysfunctional telomeres and suffered a variety of age-related afflictions that progressed in successive generations of mice. Among the conditions were testes reduced in size and depleted of sperm, atrophied spleens, damage to the intestines, and shrinkage of the brain along with an inability to grow new brain cells.

“We wanted to know: If you could flip the telomerase switch on and restore telomeres in animals with entrenched age-related disease, what would happen?” explained DePinho. “Would it slow down aging, stabilize it, or even reverse it?”

Rather than supply the rodents with supplemental telomerase, the scientists devised a way to switch on the animals’ own dormant telomerase gene, known as TERT. They engineered the endogenous TERT gene to encode a fusion protein of TERT and the estrogen receptor. This fusion protein would only become activated with a special form of estrogen. With this setup, scientists could give the mice an estrogen-like drug at any time to stimulate the TERT-estrogen receptor fusion protein and make it active to maintain telomeres.

Against this backdrop, the researchers administered the estrogen drug to some of the mice via a time-release pellet inserted under the skin. Other animals, the controls, were given a pellet containing no active drug.

After four weeks, the scientists observed remarkable signs of rejuvenation in the treated mice. Overall, the mice exhibited increased levels of telomerase and lengthened telomeres, biological changes indicative of cells returning to a growth state with reversal of tissue degeneration, and increase in size of the spleen, testes, and brain. “It was akin to a Ponce de León effect,” noted DePinho, referring to the Spanish explorer who sought the mythical Fountain of Youth.

“When we flipped the telomerase switch on and looked a month later, the brains had largely returned to normal,” said DePinho. More newborn nerve cells were observed, and the fatty myelin sheaths around nerve cells — which had become thinned in the aged animals — increased in diameter. In addition, the increase in telomerase revitalized slumbering brain stem cells so they could produce new neurons.

To show that all this new activity actually caused functional improvements, the scientists tested the mice’s ability to avoid a certain area where they detected unpleasant odors that they associated with danger, such as scents of predators or rotten food. They had lost that survival skill as their olfactory nerve cells atrophied, but after the telomerase boost, those nerves regenerated and the mice regained their crucial sense of smell.

“One of the most amazing changes was in the animals’ testes, which were essentially barren as aging caused the death and elimination of sperm cells,” recounted DePinho. “When we restored telomerase, the testes produced new sperm cells, and the animals’ fecundity was improved — their mates gave birth to larger litters.”

The telomerase boost also lengthened the rodents’ life spans compared to their untreated counterparts — but they did not live longer than normal mice, said the researchers.

The authors concluded, “This unprecedented reversal of age-related decline in the central nervous system and other organs vital to adult mammalian health justifies exploration of telomere rejuvenation strategies for age-associated diseases.”

Other authors include members of the DePinho research group and Eleftheria Maratos-Flier, an HMS professor of medicine at Beth Israel Deaconess Medical Center.

The research was supported by grants from the National Institutes of Health and the Belfer Foundation.

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