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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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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
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June 17, 2011--------News Archive

Postnatal Depression Linked to Depression in Child
The effects of maternal depression on the likelihood of the child to develop depression may begin as early as infancy.

First Diagnostic Test for Hereditary Child's Disease
A breakthrough in genetic research has uncovered the defect behind a rare hereditary child’s disease that inhibits the body’s ability to break down vitamin D.

Walking, Sex, Spicy Food Favored to Bring On Labor
Near the end of pregnancy, some women take it upon themselves to try to induce labor, mostly by walking, having sex, eating spicy food or stimulating their nipples.


June 16, 2011--------News Archive

Effects of Premature Birth Can Reach Into Adulthood
Premature infants are less healthy, have more social and school struggles and face a greater risk of heart-health problems in adulthood.

Mouse Genetics Are A Resource For Human Genetics
Mouse gene knockouts will empower mammalian gene studies for a generation.


June 15, 2011--------News Archive

Taming the Molecule's Dr. Jekyll and Mr. Hyde
Two forms of a molecule are called enantiomers and can have radically different properties in biology. Thalidomide is a good example of how different forms of the same molecule can have disastrous consequences.

Fear Activates Young, Immature Infant Brain Cells
Fear burns memories into our brain, and new research by University of California, Berkeley, neuroscientists explains how.


June 14, 2011--------News Archive

Malnourishment - Pregnant or Lactating - Key to Diseases In Children
Study in primates establishes critical role that undernourishment in mothers-to-be and lactating females has in creating type 2 diabetes in offspring.

We Are All Mutants
The first whole-genome measure of human mutation predicts 60 new mutations exist within each of us at birth.

Canadian Women On Technology Used in Childbirth
This generation's choice of C-section does not reflect knowledge of the procedure's complications to mother and child.


June 13, 2011--------News Archive

Cell Division Linked to Oxygen Levels
Johns Hopkins reports that the MCM proteins, which promote cell division, also directly control the oxygen-sensing HIF-1 protein which controls cell division.

Many Genetic Keys Needed to Unlock Autism
Hundreds of small genetic variations are associated with autism spectrum disorders, including an area of DNA that may be key to understanding why humans are social animals.

Children Eschew the Fat - If Dad Says So
Dad's choice of where to eat could literally tip the scales on his children's health.

Mom's B Vitamins Lower Child's Colorectal Cancer
Mice born to mothers who are fed a diet supplemented with B vitamins are less likely to develop intestinal tumors

WHO Child Growth Charts

Cells grow abundant when oxygen is available, and generally stop when it is scarce.

Although this seems straightforward, no direct link ever has been established between the cellular machinery that senses oxygen and that which controls cell division.

Now, in the June 10 issue of Molecular Cell, researchers at Johns Hopkins report that the MCM [mini-chromosome maintenance] proteins, which promote cell division, also directly control the oxygen-sensing HIF-1 protein.

"It's always been a mystery why a vast excess of MCM proteins is present in cells, but now we have discovered at least one reason," says Gregg Semenza, M.D., Ph.D., the C. Michael Armstrong Professor of Medicine, director of the vascular program in Hopkins' Institute for Cell Engineering and a member of the McKusick-Nathans Institute of Genetic Medicine. "Our data indicate that MCMs mediate crosstalk between the cell division machinery and proteins that help cells react to changes in their surroundings."

Since discovering HIF-1 in the 1990s, Semenza's team has been studying how it works to sense oxygen levels and turn on genes that help cells survive when oxygen is low.

To find proteins that HIF-1 physically interacts with, the team went on a biochemical fishing expedition and, using HIF-1 as bait, pulled out MCM7. MCM7 is a member of a larger group of related proteins that are known to bind to DNA and start its duplication when a cell gets ready to divide. Using a different protein-binding technique, the team then found that HIF-1 also binds to MCM3.

When it senses low oxygen levels, HIF-1 turns on genes that enable cells to adapt, such as genes that stimulate the growth of new blood vessels and genes that alter a cell's metabolism to change how much oxygen it consumes for energy generation.

To understand what MCM proteins do to or with HIF-1, the researchers examined how well HIF-1 turns on genes in the presence and absence of MCM3 or 7. They found when the levels of MCM proteins were increased, the activity of HIF-1 went down, while reducing the levels of MCMs, led to increased HIF-1 activity.

"HIF-1 instructs cells not to divide, since more cells will consume more oxygen, making any shortage of oxygen even worse, while the role of MCMs is to trigger cell division" says Semenza. "So it's not surprising that MCMs would oppose the action of HIF-1."

The team also noticed that there seemed to be less MCM7 present when cells were exposed to low oxygen for 24 hours.

To see if this had anything to do with HIF-1, they first turned up HIF-1 levels in cells -- by either exposing them to low oxygen or treating them with a drug that boosts HIF-1 production -- and found a decrease in the levels of MCM proteins 24 hours later.

Separately, they removed HIF-1 from cells, then exposed the cells to low oxygen and found no change in MCM protein levels, allowing the group to conclude that HIF-1 controls MCM proteins as well, so that the MCMs and HIF-1 oppose each other's action.

"It's like a tug of war," says Semenza. "When oxygen and nutrients are plentiful, MCMs win, and cells divide. When oxygen is low, HIF-1 wins and cell division is prevented. The mutual antagonism may be critical for tightly controlling cell growth based on oxygen availability."

This study was funded by the National Institutes of Health and the Johns Hopkins Institute for Cell Engineering. Authors on the paper are Maimon Hubbi, Weibo Luo, Jin Baek and Gregg Semenza, all of Johns Hopkins.

Original article: http://www.hopkinsmedicine.org/news/media/

releases/johns_hopkins_researchers_link_cell_division_and_oxygen_levels