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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 SemestersFetal 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 HemispheresFemale Reproductive SystemEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterSecond TrimesterFirst TrimesterFertilizationDevelopmental Timeline
CLICK ON weeks 0 - 40 and follow along every 2 weeks of fetal development
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Home | Pregnancy Timeline | News Alerts |News Archive Dec 2, 2014

This new data provides information from the mouse ENCODE project, that the mouse
is an appropriate animal model for studying human biology and disease.




Evolutionary controls seen in thousands of genes

Data from the Mouse ENCODE project reveals a comprehensive list of some 6600 genes where the number of "turned on" genes exists within a restricted range for both mice and humans.

An international research team led by Professor Thomas R. Gingeras of Cold Spring Harbor Laboratory (CSHL) and Roderic Guigo (Centre For Genomic Regulation, Barcelona) identified those genes. They found that constraint in the "reading" or "turning on" of genes is unrelated to the amount of similarity between gene sequences.

These 6600 genes represent about a third of the total number of genes typically active in cells in both species. Researchers believe the study provides new information that keeps the mouse an excellent model organism for continued study of human disease and general biology.

All of the newly published research is from the mouse ENCODE project, an extension of the human ENCODE (ENCyclopedia Of DNA Elements) program. ENCODE is building a comprehensive database of the human genome including genes that code for proteins, non-protein-coding genes and elements that control which genes are turned on or off and when.

"We believe that evolution has placed remarkably narrow constraints on the expression of these 6600 genes, as reflects their importance to the operation of all tissues in either species.

Thomas R. Gingeras PhD, Head of Functional Genomics, Th Cold Spring Harbor Laboratory.

The 6600 genes identified, reflect gene expression that varies over an approximate range of a hundred cell types — as compared to the remaining two-thirds of expressed (turned on and active) genes which cover over a 100,000- cell types.

Gingeras and collaborators also found six very different animal species — from chickens to humans — where 2500 genes are shared in common. Within these six species, gene expression is sharply constrained to the same narrow range as observed between mice and humans. This is more evidence for an evolution regulated mechanism being shared between them that is very old and very important.

These results are part of a large body of research from the Mouse ENCODE project now being published by this international consortium, of which Gingeras is a principal invesitgator. Shared findings are in four papers in Nature. Their work examines the genetic and biochemical sequences involved in regulating mouse and human genomes.

"The mouse has long been a mainstay biological research model. These results provide a wealth of information on how the mouse genome works, and a foundation on which scientists can build to further understand both mouse and human biology. The collection of mouse ENCODE data is a tremendously useful resource for the research community."

Eric Green, MD, PhD, NHGRI Director

More than a dozen related studies stemming from the Mouse ENCODE data also appear or will appear in journals such as Genome Research, Genome Biology, Nature Communications, and Blood.

Cold Spring Harbor Laboratory
We characterized by RNA-seq the transcriptional profiles of a large and heterogeneous collection of mouse tissues, augmenting the mouse transcriptome with thousands of novel transcript candidates. Comparison with transcriptome profiles obtained in human cell lines reveals substantial conservation of transcriptional programs, and uncovers a distinct class of genes with levels of expression across cell types and species, that have been constrained early in vertebrate evolution. This core set of genes capture a substantial and constant fraction of the transcriptional output of mammalian cells, and participates in basic functional and structural housekeeping processes common to all cell types. Perturbation of these constrained genes is associated with significant phenotypes including embryonic lethality and cancer. Evolutionary constraint in gene expression levels is not reflected in the conservation of the genomic sequences, but it is associated with strong and conserved epigenetic marking, as well as to a characteristic post-transcriptional regulatory program in which sub-cellular localization and alternative splicing play comparatively large roles.

"Enhanced Transcriptome Maps from Multiple Mouse tissues Reveal Evolutionary Constraint in Gene Expression for Thousands of Genes" can be obtained at bioarxiv.org: http://www.biorxiv.org/content/early/2014/10/30/010884. The authors are: Dmitri Pervouchine, Sarah Djebali, Alessandra Breschi, Carrie A Davis, Pablo Prieto Barja, Alex Dobin, Andrea Tanzer, Julien Lagarde, Chris Zaleski, Lei-Hoon See, Meagan Fastuca, Jorg Drenkow, Huaien Wang, Giovanni Bussotti, Baikang Pei, Suganthi Balasubramanian, Jean Monlong, Arif Harmanci, Mark Gerstein, Michael A Beer, Cedric Notredame, Roderic Guigo, and Thomas R Gingeras. Four papers produced collectively by the Mouse ENCODE Consortium appear on November 19, 2014 in Nature. These papers can be obtained at: http://www.nature.com/nature/index.html

The laboratory mouse shares the majority of its protein-coding genes with humans, making it the premier model organism in biomedical research, yet the two mammals differ in significant ways. To gain greater insights into both shared and species-specific transcriptional and cellular regulatory programs in the mouse, the Mouse ENCODE Consortium has mapped transcription, DNase I hypersensitivity, transcription factor binding, chromatin modifications and replication domains throughout the mouse genome in diverse cell and tissue types. By comparing with the human genome, we not only confirm substantial conservation in the newly annotated potential functional sequences, but also find a large degree of divergence of sequences involved in transcriptional regulation, chromatin state and higher order chromatin organization. Our results illuminate the wide range of evolutionary forces acting on genes and their regulatory regions, and provide a general resource for research into mammalian biology and mechanisms of human diseases.

The work described in this release was supported by the National Human Genome Research Institute (NHGRI); the Spanish Plan Nacional; the ERC; LaCaixa; and the EU-FP7 quantomics project.

ENCODE and mouseENCODE projects are supported by the National Human Genome Research Institute (NHGRI), part of National Institutes of Health (NIH).

About Cold Spring Harbor Laboratory
Celebrating its 125th anniversary in 2015, Cold Spring Harbor Laboratory (CSHL) has shaped contemporary biomedical research and education with programs in cancer, neuroscience, plant biology and quantitative biology. Home to 8 Nobel Prize winners, the private, non-profit Laboratory is more than 600 researchers and technicians strong. The Meetings & Courses program hosts more than 12,000 scientists from around the world each year on its campuses in Long Island and in Suzhou, China. The Laboratory's education arm also includes an academic publishing house, a graduate school and programs for middle and high school students and teachers. For more information, visit http://www.cshl.edu

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