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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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Disclaimer: The Visible Embryo web site is provided for your general information only. The information contained on this site should not be treated as a substitute for medical, legal or other professional advice. Neither is The Visible Embryo responsible or liable for the contents of any websites of third parties which are listed on this site.
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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 weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
 
August 19, 2011--------News Archive

Hydrodynamics Transform Embryonic Cells Into Us
H
ydrodynamics can contribute to our understanding of how a cluster of embryonic cells can transform into an animal.

New Data on Adenine, a Crucial Building Block of Life
The five nucleic acids making up DNA are some of the few that can withstand ultraviolet light. But adenine turns out to have an extensive range of respones.


August 18, 2011--------News Archive

Pluripotent Stem Cells Developmentally Immature
Researchers have discovered that though similar, induced pluripotent stem cells are similar to embryonic stem cells, but are much more developmentally immature.

Change the Environment, Not the Child
National study finds equal benefit for children with cerebral palsy.


August 17, 2011--------News Archive

Molecular Delivery Serves Gene Therapy Cocktail
Scientists have devised a gene therapy cocktail that has the potential to treat some inherited diseases associated with "misfolded" proteins.

Children of Depressed Mothers Have a Different Brain
MRI scans show their children have an enlarged amygdala.

Discovery Likely to Spur Medicine and Human Health
Scientists have gained new insight into the relationship between two proteins that, out of balance, can prevent normal development of stem cells in the heart.


August 16, 2011--------News Archive

Study Finds New Role for Protein in Hearing
A protein involved in sound sensing in the inner ear may also play a role in transmitting sound information to the brain.

Retinoblastoma Made of Hybrid Cells
Scientists settle a century-old debate about retinoblastoma's beginnings and identify new targets for treating the childhood eye tumor.

Can Oral Care for Babies Prevent Future Cavities?
A recent study confirms the presence of bacteria associated with early childhood caries (ECC) in infant saliva.


August 15, 2011--------News Archive

Slowing the Allergic March
Researchers identify a target that could combat allergies of early childhood.

Gene Clue in the Development of Rheumatoid Arthritis
Findings will help lead to personalized therapies for common, complex illnesses characterized by abnormal immune responses.

Sight Re-Constructs Moving Objects: One by One
Our visual system groups areas of the world with similar characteristics, such as color, shape, or motion.

WHO Child Growth Charts

Stem cell researchers at UCLA have discovered that three types of cells derived from human embryonic stem cells and induced (converted into a stem cell within a laboratory setting) pluripotent stem cells are similar to each other, but are much more developmentally immature than previously thought when compared to those same cell types taken directly from human tissue.

The researchers, from the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA, found that the progeny of the human embryonic stem cells and induced pluripotent stem cells (iPS) were more similar to cells found within the first two months of fetal development than anything later. This could have implications both clinically and for disease modeling, said William Lowry, senior author of the study and an assistant professor of molecular, cell and developmental biology in the Life Sciences.

The two-year study was published today in the peer-reviewed journal Cell Research.

"Once we found that the human embryonic stem cell- and the iPS-derived progeny were similar, we wanted to understand how similar the progeny were to the same cells taken directly from human tissue," Lowry said.

"What we found, looking at gene expression, was that the cells we derived were similar to cells found in early fetal development and were functionally much more immature than cells taken from human tissue. This finding may lead to exciting new ways to study early human development, but it also may present a challenge for transplantation, because the cells you end up with are not something that's indicative of a cell you'd find in an adult or even in a newborn baby."

There might also be challenges in disease modeling, unless you're modeling diseases that occur within the first two months of development, Lowry said.

Employing the most commonly used methods for deriving cells from embryonic stem cells and iPS cells, Lowry and his team differentiated these human pluripotent stem cells into neural progenitor cells, which create neurons and glia, hepatocytes, the main tissue found in the liver, and fibroblasts, common to the skin. They selected those cell types because they are easy to identify and are among the most commonly differentiated cells made from pluripotent stem cells. They also represent cell types found in the three germ layers, the endoderm, mesoderm and ectoderm, where the first cell fate decisions are made, Lowry said.

The progeny of the human pluripotent stem cells were compared to each other using their gene expression patterns, functionality and appearance. There was essentially little or no difference between them, Lowry said. Then the work began to compare them to equivalent cell types found in humans.

"One important reason to do this is to ensure that the cells we are creating in the Petri dish and potentially using for transplantation are truly analogous to the cells originally found in humans," said Michaela Patterson, first author of the study and a graduate student researcher. "Ideally, they should be a similar as possible."

What the team found was that while the progeny were alike, they bore striking differences from the same cells found in humans when analyzing their gene expression. A significant number of genes, about 100, were differentially expressed in the cell types made from pluripotent stem cells, Lowry said.

About half of those differentially expressed genes are normally thought to be strictly expressed in pluripotent stem cells, which have the potential to differentiate into any cell of the three germ layers. Those genes had not been turned off even after the cell had differentiated into either a neural progenitor cell, hepatocyte or a fibroblast, Patterson said.

"Previously, we assumed that all pluripotency genes get shut off right away, after the fetus begins developing," Patterson said. "We found that this is not the case, and in fact some of these genes remain expressed."

The differences in gene expression could be problematic, Lowry said, because some of these same differentially expressed genes in the progeny are genes that are expressed during cancer development. Also worrisome was their developmental maturity – would they work correctly when transplanted into humans? As part of their study, the team left the differentiating cells in culture about a month longer to see if they would further mature, and there was some modest but statistically significant maturation. However, genetic discrepancies remained.

These discrepancies could be critical, Patterson said, particularly in the hepatocytes. During fetal development, these cells express proteins that aid the metabolism of the fetus, a role they don't play later in adults.

"The roles these cells play in the fetus and the adult are inherently different," she said. "It may be that the progeny, if transplanted into a human, would mature to the same levels as those found in the adult liver. We don't know."

The team then compared the progeny to cells from humans that were closer to the progeny's developmental maturity and found that the two types of cells were indeed becoming more similar in gene expression and functionality, Lowry said.

The UCLA team is not the first to suggest that the progeny of human pluripotent stem cells reflect an early developmental immaturity. However, these data put a more precise window on their developmental age.

Going forward, Lowry and his team are going to study the 100 genes being differentially expressed in the progeny to see if manipulating some or all of them results in the maturation of the cells.

"These findings provide support for the idea that human pluripotent stem cells can serve as useful in vitro models of early human development, but also raise important issues for disease modeling and the clinical applications of their derivatives," the study states.

The study was funded in part by a seed grant and training grants from the California Institute of Regenerative Medicine, the Basil O'Connor Started Scholar Award and the Fuller Foundation.

The stem cell center was launched in 2005 with a UCLA commitment of $20 million over five years. A $20 million gift from the Eli and Edythe Broad Foundation in 2007 resulted in the renaming of the center. With more than 200 members, the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research is committed to a multi-disciplinary, integrated collaboration of scientific, academic and medical disciplines for the purpose of understanding adult and human embryonic stem cells. The center supports innovation, excellence and the highest ethical standards focused on stem cell research with the intent of facilitating basic scientific inquiry directed towards future clinical applications to treat disease. The center is a collaboration of the David Geffen School of Medicine, UCLA's Jonsson Cancer Center, the Henry Samueli School of Engineering and Applied Science and the UCLA College of Letters and Science. To learn more about the center, visit our web site at http://www.stemcell.ucla.edu. To learn more about the center, visit our web site at http://www.stemcell.ucla.edu.