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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 June 26, 2013

 

Lysosomal storage disorders—Gaucher's Disease (above)

Lysosomal storage diseases are generally classified by the nature of the
stored material involved and can be broadly broken into the following:

Lipid storage disorders, mainly sphingolipidoses
(including Gaucher's and Niemann-Pick diseases)

Gangliosidosis, including Tay-Sachs disease

Leukodystrophies

Mucopolysaccharidoses (including Hunter
syndrome and Hurler disease)


Glycoprotein storage disorders

Mucolipidoses

Glycogen storage disease type II (Pompe disease)
is also a defect in lysosomal metabolism.







WHO Child Growth Charts

 

 

 

RNA escape from cells could shut off disease-causing gene

Nanoparticles that deliver short strands of RNA offer a way to treat cancer and other diseases by shutting off malfunctioning genes.

by Anne Trafton, MIT News Office

Although this approach has shown some promise, scientists are still not sure exactly what happens to nanoparticles once they get inside their target cells. A new study from MIT sheds light on the nanoparticles’ fate and suggests new ways to maximize delivery of the RNA strands they are carrying, known as short interfering RNA (siRNA).

“We’ve been able to develop nanoparticles that can deliver payloads into cells, but we didn’t really understand how they do it,” says Daniel Anderson, the Samuel Goldblith Associate Professor of Chemical Engineering at MIT. “Once you know how it works, there’s potential that you can tinker with the system and make it work better.”

Anderson, a member of MIT’s Koch Institute for Integrative Cancer Research and MIT’s Institute for Medical Engineering and Science, is the leader of a research team that set out to examine how nanoparticles and their drug payloads are processed at a cellular and subcellular level.

Their findings appear in the June 23 issue of Nature Biotechnology. Robert Langer, the David H. Koch Institute Professor at MIT, is also an author of the paper.

One RNA-delivery approach that has shown particular promise is packaging the strands with a lipidlike material; similar particles are now in clinical development for liver cancer and other diseases.


Through a process called RNA interference, siRNA targets messenger RNA (mRNA), which carries genetic instructions from a cell’s DNA to the rest of the cell.

When siRNA binds to mRNA, the message carried by that mRNA is destroyed. Exploiting that process could allow scientists to turn off genes that allow cancer cells to grow unchecked.


Scientists already knew that siRNA-carrying nanoparticles enter cells through a process, called endocytosis, by which cells engulf large molecules. The MIT team found that once the nanoparticles enter cells they become trapped in bubbles known as endocytic vesicles. These bubbles prevent most of the siRNA from reaching its target mRNA, which is located in the main body of the cell (known as the cytosol).

This happens even with the most effective siRNA delivery materials, suggesting that there is a lot of room to improve the delivery rate, Anderson says.

“We believe that these particles can be made more efficient. They’re already very efficient, to the point where micrograms of drug per kilogram of animal can work, but these types of studies give us clues as to how to improve performance,” Anderson says.

Molecular traffic jam

Researchers found that once cells absorb the lipid-RNA nanoparticles, they are broken down within about an hour and excreted from the cells.

They also identified a protein called Niemann Pick type C1 (NPC1) as one of the major factors in the nanoparticle-recycling process. Without this protein, the particles could not be excreted from the cells, giving the siRNA more time to reach its targets.

“In the absence of the NPC1, there’s a traffic jam, and siRNA gets more time to escape from that traffic jam because there is a backlog,” says Gaurav Sahay, an MIT postdoc and lead author of the Nature Biotechnology paper.


In studies of cells grown in the lab without NPC1, researchers found the level of gene silencing achieved with RNA interference was 10 to 15 times greater than that in normal cells.

Lack of NPC1 also causes a rare lysosomal storage disorder that is usually fatal in childhood. The findings suggest that patients with lysosomal storage disorder might benefit greatly from potential RNA interference therapy delivered by nanoparticle.

Researchers are now planning to study the effects of knocking out the NPC1 gene on siRNA delivery in animals, with an eye toward testing possible siRNA treatments for the disorder.


Researchers are also looking for other factors in nanoparticle recycling that could make good targets for slowing down or blocking the recycling process, which they hope could help make RNA interference drugs much more potent. Possible ways to impede recycling could include administering a drug that interferes with nanoparticle recycling, or creating nanoparticle materials that more effectively evade the recycling process.

The research was funded by Alnylam Pharmaceuticals and the National Heart, Lung, and Blood Institute.

Original press release:http://web.mit.edu/press/2013/enhancing-rna-interference.html