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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 SemestersFemale Reproductive SystemFertilizationThe Appearance of SomitesFirst TrimesterSecond TrimesterThird TrimesterFetal 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 HemispheresEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
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December 2, 2011--------News Archive

Working Moms Multitask More Than Dads
Not only are working mothers multitasking more frequently than working fathers, but their multitasking experience is more negative as well.

Unlocking the Genetic Mystery of Sarcomas
Study uncovers potential targets for treating a disease affecting children and adults.

When Babies Wake, Cortisol Rises to Mom's Level
The hormone cortisol in adults rises and lowers according to stress. But in babies cortisol remains level following waking - and tunes in with mom's level.

December 1, 2011--------News Archive

Home Births – Then and Now
A comparison of home-birth trends of the 1970s finds many similarities – and some differences – related to trends in home births today.

Risk of Suicide In Pregnant Women, New Mothers
An analysis of new data highlights risk factors that could be targeted by interventions.

Addiction Damages PreFrontal Cortex
Brain structure-function impairment may be related to an inability to assess rewards and consequences, behavior associated with addiction.

November 30, 2011--------News Archive

Gene Puts Brakes On Breast Cancer Progression
Newly published research explores the role of gene in tumour suppression

‘Perfect Parent’ Not A Good Idea
Seeking perfection as a parent works better for dads than for moms.

Kindergarten Friendships Matter, Especially for Boys
High-quality friendships in kindergarten may mean that boys will have fewer behavior problems and better social skills in first and third grades.

November 29, 2011--------News Archive

Cleft Lip Corrected Genetically in Mouse Model
Scientists have successfully genetically repaired cleft lips in mice embryos specially engineered for the study of cleft lip and cleft palate.

Common Herbicide Creates Reproductive Problems
International researchers link exposure to atrazine – an herbicide widely used in the U.S. and more than 60 other nations – to reproductive problems in animals.

Environment and Diet Leave Imprints On the Heart
DNA methylation in the human heart has revealed the 'missing link' between lifestyle and health, and may indicate methylation creates the equivalent of 5, 6, 7 and 8 bases by modifying Cytosines across our entire genome.

November 28, 2011--------News Archive

Role of Nuclear Membrane Protein in Organ Growth
Scientists had thought B-type lamin proteins were vital to embryonic stem cells; but they are more critical to organ formation.

Hormone Hepcidin May Control Atherosclerosis
Hepcidin is a hormone produced by the liver and regulates iron transport. Blocking its production encourages macrophages to counter atherosclerosis.

Two Enzymes Stamp DNA with "Turn Off" Signal
Inside the cell nucleus, DNA is wound around spool-like proteins called histones. Two modifications in this attachment tell a portion of the DNA to be on or off.

WHO Child Growth Charts


Structural integrity of the prefrontal cortex modulates electrocortical sensitivity to monetary reward. Impairments in these regions may also be related to decreased ability to assess and respond to other modulated rewards and consequences, such as those associated with using addictive drugs.

The more gray matter you have in the decision-making, thought-processing part of your brain, the better your ability to evaluate rewards and consequences.

That may seem like an obvious conclusion, but a new study conducted at the U.S. Department of Energy’s Brookhaven National Laboratory is the first to show this link between structure and function in healthy people — and the impairment of both structure and function in people addicted to cocaine.

The study appears in the Journal of Cognitive Neuroscience.

“This study documents for the first time the importance to reward processing of gray matter structural integrity in the parts of the brain’s prefrontal cortex that are involved in higher-order executive function, including self-control and decision-making,” said Muhammad Parvaz, a post-doctoral fellow at Brookhaven Lab and a co-lead author on the paper.

“Previous studies conducted at Brookhaven and elsewhere have explored the structural integrity of the prefrontal cortex in drug addiction and the functional components of reward processing, but these studies were conducted separately,” Parvaz said. “We wanted to know whether the specific function of reward processing could be ‘mapped’ onto the underlying brain structure — whether and how these two are related,” he added.

Differences in gray matter volume — the amount of brain matter made up of nerve cell bodies, as opposed to the “white matter” axons that form the connections between cells — have been observed in a range of neuropsychiatric diseases when compared with healthy states, explained Anna Konova, the other co-lead author on the paper. “We wanted to know more about what these differences mean functionally in healthy individuals and in drug-addicted individuals,” she said.

To explore this structure-function relationship, the scientists used magnetic resonance imaging (MRI) brain scans to measure brain volume in 17 healthy people and 22 cocaine users. The scans collect structural measurements for the entire brain, and can be analyzed voxel-by-voxel — the equivalent of three-dimensional pixels — to get detailed measurements for individual brain regions.

Within a short period of the MRI scans, the scientists also used electrodes placed on the research subjects’ scalps to measure a particular electrical signal known as the P300 (an event-related potential derived from an ongoing electroencephalogram, or EEG, that is time-locked to a particular event).

This specific measure can index brain activity related to reward processing. During these electrical recordings, the subjects performed a timed psychological task (pressing buttons according to a specific set of rules) with the prospect of earning varying levels of monetary reward, from no money up to 45 cents for each correct response with a total potential reward of $50.

Previous studies by the research team have shown that, in healthy subjects, the P300 signal increases in magnitude with the amount of monetary reward offered. Cocaine-addicted individuals, however, do not exhibit this differential response in the P300 measure of brain activity, even though they, like the healthy subjects, rate the task as more interesting and exciting when the potential reward is greater.

The current study extended these results by linking them for the first time with the structural measurements.

The scientists used statistical methods to look for correlations between the difference in brain activity observed in the high-reward and no-reward conditions — how much the brain’s P300 response changed with increasing reward — and the gray matter volume in various parts of the brain as measured voxel-by-voxel in the MRI scans.

In the healthy subjects, the magnitude of change in the P300 signal with increasing reward was most strongly correlated with the volume of gray matter in three regions of the prefrontal cortex.

“The higher the gray matter volume in those particular regions, the more brain activity increased for the highest monetary reward as compared to the non-reward condition,” Konova said.

The cocaine-addicted individuals had reduced gray matter volume in these regions compared with the healthy subjects, and no detectable differences between the reward conditions in the P300 measure of brain activity. There were also no significant correlations between the former and latter — structure and function measures — in the cocaine-addicted subjects.

“These findings suggest that impaired reward processing may be attributed to deficits in the structural integrity of the brain, particularly in prefrontal cortical regions implicated in higher order cognitive and emotional function,” Parvaz said. “This study therefore validates the use of the structural measures obtained by MRI as indicative of functional deficits.”

The implications are important for understanding the potential loss of control and disadvantageous decision-making that can occur in people suffering from drug addiction, Konova explained: “These structure-function deficits may translate into dysfunctional behaviors in the real world. Specifically, impaired ability to compare rewards, and reduced gray matter in the prefrontal cortex, may culminate in the compromised ability to experience pleasure and to control behavior, especially in high-risk situations — for example, when craving or under stress — leading individuals to use drugs despite catastrophic consequences.”

The authors acknowledge that there are still questions about whether these changes in brain structure and function are a cause or a consequence of addiction. But the use of multimodal imaging techniques, as illustrated by this study, may open new ways to address these and other questions relevant to understanding human motivation in both health and disease states, with particular relevance to treating drug addiction.

This research was performed at Brookhaven Lab under the guidance of Rita Goldstein, Director of Brookhaven Lab’s Neuropsychoimaging Group and the corresponding author on the paper. Dardo Tomasi of the National Institute on Alcohol Abuse and Alcoholism, who runs Brookhaven’s MRI facility, and Nora Volkow, Director of the National Institute on Drug Abuse (NIDA), were co-authors. The research was funded by a grant to Goldstein from the National Institutes of Health and by the General Clinical Research Center of Stony Brook University.

Scientific Paper: Structural Integrity of the Prefrontal Cortex Modulates Electrocortical Sensitivity to Reward

Original article: http://www.bnl.gov/bnlweb/pubaf/pr/PR_display.asp?prID=1355