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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 23, 2011--------News Archive

Defending the Genome
New research illustrates how the genome adapts to a transposon invasion that threatens fertility in the fruit fly. The same mechanism may exist in humans.

Multiple Sclerosis Not an Immune System Disease
Recent research argues that multiple sclerosis, long viewed as primarily an autoimmune disease, is more similar to hardening of the arteries.

Toddlers Rely On Others To Monitor Their Speech
When grown-ups and kids speak, they listen to the sound of their voice and make corrections based on that auditory feedback - something toddlers can't do.

December 22, 2011--------News Archive

How Pregnancy Changes a Woman’s Brain
At no other time in a woman’s life does she experience such massive hormonal fluctuations as during pregnancy.

New Device To Support Improved Newborn Health
Fetal heart rate monitor also tracks how well an infant is using oxygen.

Weight Reduction Through Mindful Eating
Pregnancy is a time when heavy women tend to gain an excessive amount of weight and later find it very hard to lose.

December 21, 2011--------News Archive

Breast Cancer, Heart Disease Share Common Roots
Women who are at risk for breast cancer may also be at greater risk for heart disease.

Breastfeeding Promotes Healthy Growth
Breastfeeding lowers the growth hormones IGF-I and insulin, promoting slightly slower growth and reducing adult risk of overweight and diabetes.

First Months of Life Shape Flavor Preferences
Early dietary experience shapes salt preference of infants and preschoolers.

December 20, 2011--------News Archive

Babies Remember Even As They Seem to Forget
How much do babies remember about the world around them, and what details do their brains need to absorb to help them keep track of things and people?

Safer Treatment for Asthma, Allergies, Arthritis?
Found, a missing link between our biological clock and sugar metabolism which may avoid serious side effects of drugs used for asthma, allergies and arthritis.

Endometriosis Link to Inflammatory Bowel Disease
Increased risk of inflammatory bowel disease is found in women with endometriosis in a nationwide Danish study.

December 19, 2011--------News Archive

Gene Discovered that Causes Rare Infant Epilepsy
The childhood disorder PKD is linked to a mysterious gene found in the brain called PRRT2 - a gene with little resemblance to anything in the human genome.

Don't Buy Noisy Toys!
If listened to at arms length, some popular items can permanently damage children's hearing - and hearing loss is not curable.

Childhood Cancer Drugs Cure, Later Cause Problems
Study indicates that drug toxicity may be related to genetic factors increasing risk of cardiomyopathy significantly in individuals with two copies of specific gene.

WHO Child Growth Charts

BMI For Adults Widget


       



Small, mobile sequences of DNA left over from viruses, called transposons or "jumping genes" (because of their ability to move around the genome), pose a significant threat to the genetic integrity and stability of any organism.

Considered genetic parasites, transposons are believed to make up as much as 50 percent of the human genome. Because of the damage they can do to DNA, an immune-like response has evolved to turn off, or silence, them.

New research published in the journal Cell by the labs of William E. Theurkauf and Zhiping Weng at the University of Massachusetts Medical School, sheds light on how the genome defends itself from these invading DNA parasites.

While it's known that specific small RNAs called Piwi-interacting RNAs (piRNAs) are responsible for turning off transposons, how isn't fully understood.

"The genome is littered with transposons," said William E. Theurkauf, PhD, professor of molecular medicine at UMass Medical School and lead author of the study. "In Drosophila there are over 120 different forms of transposons and these are the active pathogen that we are looking at in this host-pathogen response. Meanwhile, piRNAs are produced from regions of the genome that contain bits and pieces of transposons, and are the foundation for how these elements get silenced."

To understand how a genome responds to the introduction of a new transposon, Theurkauf and colleagues turned to a wild Drosophila, or fruit flies.

Unlike standard lab-bred fruit flies, wild Drosophila contain a transposon called the P element that first appeared after scientists started breeding fruit flies in the early part of the 20th century. Lab-bred fruit flies lack the P element transposon and the maternally inherited piRNA that can silence it.

When lab-bred females are crossed with P element-carrying wild fruit flies, the off-spring are unable to turn off the invading transposon and are sterile as a result.

However, Jaspreet Khurana, a PhD student in Theurkauf's lab observed that as these flies aged the hybrids regained fertility.

"Based on the observation that the flies recovered, it seemed likely that they were learning how to shut down transposons. We decided to use their system to look at the process of adaptation to a new transposable element," said Theurkauf.

Using a multi-disciplinary approach, Theurkauf and colleagues were able to get a complete genetic sequence of the sterile, hybrid flies at various stages of development.

What they found was startling.

In the hybrid off spring, the new transposon had triggered a response that disrupted the entire piRNA machinery. Not only was the newly introduced transposon jumping around the genome and causing a problem – which was expected – but most of the 120 plus transposons in the Drosophila genome had also become active.

"This massive destabilization of the genome is probably why they're sterile," said Theurkauf.

As the hybrids aged, however, the new transposon and all the existing, resident transposons, got shut down and fertility was restored.

"We found there were two mechanisms responsible for silencing the transposons," said Weng. "For P elements it turned out the flies learned to process the piRNA transcripts inherited from the father and turn them into mature piRNAs and silence the transposon."

"The bottom line on our study is when you introduce a single, new transposon it leads to a genetic crisis that activates all the transposons in the genome and compromises fertility in these hybrids," said Theurkauf.

"Remarkably, what emerges at the other end is an organism with an altered genome architecture that functionally recharges the piRNA clusters so they more effectively silence transposons."

The University of Massachusetts Medical School, one of the fastest growing academic health centers in the country, has built a reputation as a world-class research institution, consistently producing noteworthy advances in clinical and basic research. The Medical School attracts more than $307 million in research funding annually, 80 percent of which comes from federal funding sources. The mission of the Medical School is to advance the health and well-being of the people of the commonwealth and the world through pioneering education, research, public service and health care delivery with its clinical partner, UMass Memorial Health Care. For more information, visit www.umassmed.edu.

Original article: http://www.eurekalert.org/pub_releases/2011-12/uomm-dtg122111.php

When grown-ups and kids speak, they listen to the sound of their voice and make corrections based on that auditory feedback. But new evidence shows that toddlers don't respond to their own voice in quite the same way, according to a report published online on December 22 in Current Biology, a Cell Press publication.
The findings suggest that very young children must have some other strategy to control their speech production, the researchers say.
"As they play music, violinists will listen to the notes they produce to ensure they are in tune," explained Ewen MacDonald of the Technical University of Denmark. "If they aren't, they will adjust the position of their fingers to bring the notes back in tune. When we speak, we do something very similar. We subconsciously listen to vowel and consonant sounds in our speech to ensure we are producing them correctly. If the acoustics of our speech are slightly different from what we intended, then, like the violinists, we will adjust the way we speak to correct for these slight errors. In our study, we found that four-year-olds monitor their own speech in the same way as adults. Surprisingly, two-year-olds do not."
That's despite the fact that infants readily detect small deviations in the pronunciation of familiar words and babble in a manner consistent with their native language. By the time they turn two, American children have an average vocabulary of about 300 words and appear well on their way to acquiring the sound structure of their native language.
In the experiment, adults, four-year-olds, and two-year-olds said the word "bed" repeatedly while simultaneously hearing themselves say the word "bad." (To elicit those utterances from the young children and toddlers, the researchers developed a video game in which players help a robot cross a virtual playground by saying the robot's 'magic' word "bed.")
"If they repeat this several times, adults spontaneously compensate, changing the way they say the vowel," MacDonald said. "Instead of saying the word 'bed,' they say something more like the word 'bid.'"
Four-year-olds adjusted their speech, too, the researchers show. The two-year-olds, on the other hand, kept right on saying "bed."
MacDonald says the results suggest a need to reconsider assumptions about how children make use of auditory feedback. It may be that two-year-olds depend on their parents or other people to monitor their speech instead of relying on their own voice. MacDonald notes that caregivers often do repeat or reflect back to young children what they've heard them say.
While this study involved children with normal speech development, MacDonald says they'll be exploring potential applications for understanding or addressing delayed and abnormal early speech development.