Welcome to The Visible Embryo

Google
 
Home-- -History-- -Bibliography- -Pregnancy Timeline- --Prescription Drugs in Pregnancy- -- Pregnancy Calculator- --Female Reproductive System- -Contact

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 500 educational institutions and is viewed by more than 1 million visitors each month.


WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can search all registers to identify clinical trial research underway around the world!



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.
Content protected under a Creative Commons License.
No dirivative works may be made or used for commercial purposes.



THURSDAY September 2, 2010---------News Archive
The Visible Embryo maintains a searchable database of artcles published since 2007

Nanotechnology Breakthrough in Cancer Research

Researchers clear hurdle on path toward gene-therapy treatment for disease.

Structure of an adenovirus
One of the most difficult aspects of working at the nanoscale is actually seeing the object being worked on. Biological structures like viruses are smaller than the wavelength of light, and invisible to standard optical microscopes, consequently difficult to capture in their native form.
 
A multidisciplinary research group at UCLA has now teamed up to not only visualize a virus but to use the results to adapt the virus so that it can deliver medication instead of disease.
 
In a paper published last week in the journal Science, Hongrong Liu, a UCLA postdoctoral researcher in microbiology, immunology and molecular genetics, and colleagues reveal an atomically accurate structure of the adenovirus that shows the interactions among its protein networks.

The work provides critical structural information for researchers around the world attempting to modify the adenovirus for use in vaccine and gene-therapy treatments for cancer.
 
To modify a virus for gene therapy, researchers remove its disease-causing DNA, replace it with medications and use the virus shell, which has been optimized by millions of years of evolution, as a delivery vehicle.
 
Lily Wu, a UCLA professor of molecular and medical pharmacology and co-lead author of the study, and her group have been attempting to manipulate the adenovirus for use in gene therapy, but the lack of information about receptors on the virus's surface hampered their work.
 
"We are engineering viruses to deliver gene therapy for prostate and breast cancers, but previous microscopy techniques were unable to visualize the adapted viruses," Wu said. "This was like trying to a piece together the components of a car in the dark, where the only way to see if you did it correctly was to try and turn the car on." 
 
To better visualize the virus, Wu sought assistance from Hong Zhou, a UCLA professor of microbiology, immunology and molecular genetics and the study's other lead author. Zhou uses cryo-electron microscopy (cryoEM) to produce atomically accurate three-dimensional models of biological samples such as viruses. The researchers used cryoEM to create a 3-D reconstruction of the human adenovirus from 31,815 individual particle images.
 
"Because the reconstruction reveals details up to a resolution of 3.6 angstroms, we are able to build an atomic model of the entire virus, showing precisely how the viral proteins all fit together and interact," Zhou said. An angstrom is the distance between the two hydrogen atoms in a water molecule, and the entire adenovirus is about 920 angstroms in diameter.
 
Armed with this new understanding, Wu and her group are now moving forward with their engineered versions of adenovirus to use for gene therapy treatment of cancer.
 
"This breakthrough is a great leap forward," Wu said. "If our work is successful, this therapy could be used to treat most forms of cancer, but our initial efforts have focused on prostate and breast cancers because those are the two most common forms of cancer in men and women, respectively."
 
The group is working with the adenovirus because previous research has established it as a good candidate for gene therapy as it efficiently delivers genetic materials. The virus shell is also a safe as tests have shown that the shell does not cause cancer, a problem encountered with some other virus shells. The adenovirus is relatively non-pathogenic naturally, causing only temporary respiratory illness in 5 to 10 percent of people.
 
CryoEM enables such a high-resolution reconstruction of biological structures.

In contrast, with X-ray crystallography (the conventional technique for atomic resolution models of biological structures), researchers must grow crystal structures replicating the sample - and then use diffraction to solve the crystal structure.

This technique is limited due to the difficulty of growing crystals for all proteins, samples for x-ray crystallography need to be very pure and uniform, and crystals of large complexes may not diffract to high resolution.
 
The study was funded by the National Cancer Institute and the U.S. Department of Defense.
 
The California NanoSystems Institute at UCLA is an integrated research center operating jointly at UCLA and UC Santa Barbara whose mission is to foster interdisciplinary collaborations for discoveries in nanosystems and nanotechnology; train the next generation of scientists, educators and technology leaders; and facilitate partnerships with industry, fueling economic development and the social well-being of California, the United States and the world.

WHO Child Growth Charts