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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 one million visitors each month.

Today, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than 1 million visitors each month. The field of early embryology has grown to include the identification of the stem cell as not only critical to organogenesis in the embryo, but equally critical to organ function and repair in the adult human. The identification and understanding of genetic malfunction, inflammatory responses, and the progression in chronic disease, begins with a grounding in primary cellular and systemic functions manifested in the study of the early embryo.

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 SemestersDevelopmental TimelineFertilizationFirst TrimesterSecond TrimesterThird TrimesterFirst Thin Layer of Skin AppearsEnd of Embryonic PeriodEnd of Embryonic PeriodFemale Reproductive SystemBeginning Cerebral HemispheresA Four Chambered HeartFirst Detectable Brain WavesThe Appearance of SomitesBasic Brain Structure in PlaceHeartbeat can be detectedHeartbeat can be detectedFinger and toe prints appearFinger and toe prints appearFetal sexual organs visibleBrown fat surrounds lymphatic systemBone marrow starts making blood cellsBone marrow starts making blood cellsInner Ear Bones HardenSensory brain waves begin to activateSensory brain waves begin to activateFetal liver is producing blood cellsBrain convolutions beginBrain convolutions beginImmune system beginningWhite fat begins to be madeHead may position into pelvisWhite fat begins to be madePeriod of rapid brain growthFull TermHead may position into pelvisImmune system beginningLungs begin to produce surfactant
CLICK ON weeks 0 - 40 and follow along every 2 weeks of fetal development


Fetal Timeline      Maternal Timeline      News     News Archive    Aug 27, 2015 

Gene On!






Batting practice in the genome

In the biochemical game of genetics, proteins were seen as either 'spectators' or 'players' in gene regulation. But that idea is changing. Researchers now find spectator proteins are actually at batting practice, gearing up for the big game.

Researchers discovered that proteins biochemically interact with thousands of regions in the genome in order to change its structure, but only a few actually play in the big game of turning genes on (or "expression" in gene parlance).

Research results appear in the current issue of eLife.

"The previous thinking was that these proteins were wasting time and energy, like office workers spending time on Facebook. But they're actually more like baseball players at batting practice, warming up for the real thing - the actual gene switch."

David Arnosti PhD, Professor of Biochemistry, Director of Gene Expression in Development and Disease Initiative, Michigan State University

This discovery, made while examining gene switches in the Drosophila [or fruit fly], could lead to a better understanding of the DNA/protein complexes controlling gene expression. It even points to ways these elements may have evolved and could have major ramifications on human health, potentially in treating diseases such as Alzheimer's and cancers.

"Understanding gene control switches is important to understanding how humans work and our vulnerability to disease," Arnosti adds.

Arnosti's lab has developed a new method to directly trace the biochemical impact of a regulatory protein on the embryo. Their new observations suggest previous genome-wide studies may have mistaken "batting practice" for regulatory elements — a difference that impacts our understanding how genomic mutations may affect gene expression. "Batting" practice may also serve a long-term role.

"The process provides an evolutionary opportunity. 'Practice' elements can quickly change into the real thing, allowing gene networks to easily rewire when under evolutionary pressure. This changes our evaluation of active versus pseudo gene switches - our current approach is too simplistic."

David Arnosti PhD

Using fruit flies as a model system is a matter of convenience. Fruit flies have an overall genome typical in many animals. They are inexpensive, easy to manipulate with their short life cycles.

"Fruit flies have the same molecular circuitry as humans, going back to ancient mechanisms more than 500 million years old," Arnosti adds.

Metazoan transcriptional repressors regulate chromatin through diverse histone modifications. Contributions of individual factors to the chromatin landscape in development is difficult to establish, as global surveys reflect multiple changes in regulators. Therefore, we studied the conserved Hairy/Enhancer of Split family repressor Hairy, analyzing histone marks and gene expression in Drosophila embryos. This long-range repressor mediates histone acetylation and methylation in large blocks, with highly context-specific effects on target genes. Most strikingly, Hairy exhibits biochemical activity on many loci that are uncoupled to changes in gene expression. Rather than representing inert binding sites, as suggested for many eukaryotic factors, many regions are targeted errantly by Hairy to modify the chromatin landscape. Our findings emphasize that identification of active cis-regulatory elements must extend beyond the survey of prototypical chromatin marks. We speculate that this errant activity may provide a path for creation of new regulatory elements, facilitating the evolution of novel transcriptional circuits. - See more at: http://elifesciences.org/content/4/e06394#sthash.2TSuLAGl.dpuf

Michigan State University has been working to advance the common good in uncommon ways for more than 150 years. One of the top research universities in the world, MSU focuses its vast resources on creating solutions to some of the world's most pressing challenges, while providing life-changing opportunities to a diverse and inclusive academic community through more than 200 programs of study in 17 degree-granting colleges.

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