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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 26, 2011--------News Archive


A Question of Gene Silencing
Researchers have found a new way to selectively turn off genes that don't code for proteins which will help identify each gene's function, and perhaps identify cancers.

Scented Products Emit Hazardous Chemicals
Chemical sleuthing has uncovered that fragrance in consumer laundry products contains hazardous chemicals. Some which are even carcinogens.

August 25, 2011--------News Archive

Human Stem Cells Made From Amnionic Fluid
Human epithelial cells transplanted from human amnionic fluid reduce pulmonary fibrosis, and even stimulate lung regeneration in mice.

Scale Models Rule
Body patterns stay in sync with size as an embryo grows into an adult. Observed in the wing of the fruit fly, these patterns most likely exist in all organisms.

Chronic Disease Caused by Fat Cells?
Fat cells in people with metabolic syndrome have biomarkers for insulin resistance and chronic inflammation, conditions in diabetes and cardiovascular disease.

August 24, 2011--------News Archive

In the Early Life of An Embryo, Chaos Lurks
A calcium wave sparks embryonic cell division, doubling as a synchronizer of all further cell division in order for chaos to be reined in and ordered growth to persist.

Smoking Affects Fetal Infant Brain Worse than Feared
Researchers pin-point smoking specifically and find a 40% increase in damage to the fetus.

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

Boys Reach Sexual Maturity Younger and Younger
The phase between being physically but not socially adult is getting longer.

When Cell Fishing Games Go Wrong
Trial-and-error "fishing" for DNA in the nucleus may be the most important cause of female infertility.

A Sticky Egg Captures The Sperm
A sugar molecule makes the outer coat of a human egg 'sticky', which is vital for enabling the sperm and egg to bind together.

At Last, Reason Why Stress Damages DNA
Adreneline produced by chronic stress, degrades the protein p53 which is considered a tumor suppressor protein and "guardian of the genome."

August 22, 2011--------News Archive

The Basis for Head and Sex Organ Deformities
Data reveals a possible therapy using vitamin B2 to reverse enzyme defects is specific areas of fetal development.

Mother’s BMI Linked to Fatter Babies
Babies of mothers with a higher pre-pregnancy body mass index (BMI) are fatter and have more fat in their liver, a study has found.

Celiac Disease May Explain Some Women's Infertility
A recent study found increased rates of celiac disease in women who present with unexplained infertility.

WHO Child Growth Charts

Human egg surrounded by sperm. Photo credit: BBC

Researchers have uncovered exactly how a human egg captures an incoming sperm to begin the fertilisation process, in a new study published this week in the journal Science.

The research identifies the sugar molecule that makes the outer coat of the egg 'sticky', which is vital for enabling the sperm and egg to bind together. Researchers across the world have been trying to understand what performs this task for over thirty years.

The scientists behind this study believe their work could help address some of the previously unexplained causes of human infertility and sub-fertility and be very useful for diagnosing this problem in couples who are unable to have children. It could also provide a new target for the development of natural contraceptive agents.

The international team, from the University of Missouri, the University of Hong Kong, Academia Sinica in Taiwan and Imperial College London, discovered that the sugar chain known as the sialyl-lewis-x sequence (SLeX) is highly abundant on the surface of the human egg. After experimenting with a range of synthesised sugars in the laboratory they went on to show that SLeX specifically binds sperm to an egg, and tested their findings using the outer coats of unfertilised 'non-living' human eggs.

"This exciting research is providing the first insights into the molecular events occurring at the very beginning of human life. The details we've discovered here fill in a huge gap in our knowledge of fertility and we hope they will ultimately help many of those people who currently cannot conceive," said Professor Anne Dell CBE FRS FMedSci from the Department of Life Sciences at Imperial College London, who led the team that discovered the SLeX sugars on the egg surface.

"Unravelling the composition of the sugar coat that shrouds the human egg is the culmination of many years of painstaking research by my mass spectrometry colleagues at Imperial. This endeavour was an enormously difficult task because human eggs are very tiny - about the size of a full stop - so we didn't have much material to work with."

The World Health Organization estimates that infertility affects up to 15 percent of reproductive-aged couples worldwide and almost one in every seven couples in the UK have problems conceiving a child for various clinical reasons, many of which are still unexplained by medical science.

Lead author, Dr Poh-Choo Pang, also from the Department of Life Sciences at Imperial College London, said: "We hope that our study will open up new possibilities for understanding and addressing the fertility problems that many couples face. Although clinical treatments are still a way off, we are very excited about the new research into fertility that we hope will now be possible, building on our work."

"We first proposed a model of human sperm-binding involving SLeX-like molecules on the outer covering of the human egg in 1992. Our recent studies have now confirmed that this longstanding model is correct," said corresponding author and associate professor Gary Clark, from the University of Missouri School of Medicine. "Defining how the sperm initially recognises and then penetrates the egg's sugar coat is important for the design of natural contraceptive agents and for unravelling causes of previously unexplained human infertility or sub-fertility."

A sperm 'recognises' an egg when proteins on the head of the sperm meet and match a series of specific sugars in the egg's outer coat. Once a successful match has been made, the outside surfaces of the sperm and egg bind together before they merge and the sperm delivers its DNA to the inside, fertilising the egg.

The authors of this new study used ultra-sensitive mass-spectrometric imaging technology to assess which molecules were most likely to be key in the binding process. They discovered that SLeX is abundantly found on the egg's outer coat and that it is expressed at a much higher concentration than any of the other sugars that can be found on the thick transparent shell. From these results, they deduced that SLeX was most likely to be responsible for binding with proteins on the head of the sperm.

The research team in Hong Kong tested whether SLeX was the key binding sugar using the outer coats of unfertilised and non-living human eggs, obtained by informed consent from in vitro-fertilisation patients. They carefully bisected the empty coat in a delicate procedure using a tiny knife, carried out under a powerful microscope.

The scientists treated one half with a chemical that prevented the SLeX sugar from binding, to see what effect this would have on a sperm's ability to bind to the egg. When they released sperm around the bisected egg, they found that significantly fewer bound to the treated half of the egg coat than the untreated half.

"Our knowledge on sperm-egg binding in humans is limited. The identification of SLeX would enable researchers to uncover other molecules involved in this important process of human life," said Professor William Yeung from the Department of Obstetrics and Gyneacology and the Centre for Reproduction, Development and Growth at the University of Hong Kong, who led this phase of the research.

The researchers are now keen to use the findings of this study to further investigate the proteins on the head of a sperm that enable it to recognise an egg.

This work was supported in the UK by the Biotechnology and Biological Sciences Research Council (BBSRC) and a Royal Society International Joint Project Award.