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U.S. researchers have found that Zika can attack special populations of brain cells in adult mice in the part of the brain involved in learning and memory, raising new questions about how the virus may be impacting millions of adults who have been infected with the virus. The findings, published on Thursday in the journal "Cell Stem Cell," are the first to look at whether Zika can attack the same kinds of cells in adult mice that they do in fetal mice.

Your task is to compare two groups of mice to see how well they have learned the platform location. Two reliable measures of learning in mice are 1) the speed at which they find the platform, and 2) the route which they take to the platform (i.e. do they go straight to the platform or do they get a little lost along the way?).  

Exposing mice to long periods of light each day led them to put on fat, likely because their energy-burning brown fat wasn't in good shape.  Mice exposed to long periods of light didn't eat more or exercise less than mice that kept to a 12-hour day, but their brown fat activity dropped, researchers reported in PNAS this week (May 11).

The team was grafting skin from one strain of mice to another. The new skin tended to get destroyed by the recipient animals' immune systems. But when the group injected cells from the donor mice into developing fetuses, the mice that were born were much more likely to accept the skin graft. It seemed they had been primed to the foreign cells while in the womb, and developed a tolerance.

Sonnenburg, his wife Erica, and the graduate student Samuel Smits confirmed this idea in a recent experiment. The researchers started with mice that had been raised in sterile bubbles and then loaded with identical collections of gut microbes. They then fed these mice a high-fiber diet, before randomly switching half of them to low-fiber chow for seven weeks. Predictably, the fall in fiber caused upheavals in the rodents' guts. In the low-fiber group, the numbers of 60 percent of the local microbe species fell dramatically, and some remained low even after the mice returned to high-fiber meals. Those seven low-fiber weeks left lingering scars on the animals' microbiomes.

A new study by Duke University researchers helps clarify the matter by showing how a sugar habit changes specific brain circuits, and how those changes produce cravings that reinforce the habit. The research team began by getting a group of healthy mice hooked on sugar. Similar to classic studies on drug addiction, the mice in this study were trained to press a tiny lever to receive doses of sweets. Once the mice were hooked, they continued pressing the lever even when the sweets were removed. So that was step one, establishing a behavioral pattern to get the goods.

Using an animal model for human PTSD, in which researchers conditioned mice to feel fear and then attempted to reverse it, the scientists found that blocking a single gene in mice could turn off their chronic fear response.

The blood of young and old people differs. In an article published recently in the scientific journal Blood, a research group at Lund University in Sweden explain how they have succeeded in rejuvenating the blood of mice by reversing, or re-programming, the stem cells that produce blood.

In 1977, a University of Oxford statistician named Richard Peto pointed out a simple yet puzzling biological fact: We humans should have a lot more cancer than mice, but we don't. Dr. Peto's argument was beguilingly simple. Every time a cell divides, there's a small chance it will gain a mutation that speeds its growth. Cells that accumulate several of these mutations may become cancerous. The bigger an animal is, the more cells it has, and the longer an animal lives, the more times its cells divide. We humans undergo about 10,000 times as many cell divisions as mice - and thus should be far more likely to get cancer.

Lab mice that spent just two weeks in orbit showed early signs of liver damage upon returning to Earth, raising concern about what long-duration spaceflight might do to humans, researchers said Wednesday.

Researchers led by Terra D. Barnes of Washington University discovered that their genetically-engineered mice stutter due to DNA defects in a humdrum "housekeeping" gene. This gene codes for a protein that simply places a "routing tag" on certain enzymes that shred cellular trash. The tag ensures that the shredding enzymes end up in chambers called lysosomes, basically the cell's garbage disposal. It's a mundane cellular activity, yet mutations in the same process in humans have also been linked to stuttering-a bizarrely specific condition for such a general gene. And, so far, scientists have no idea why the two are linked.

Of two genetically identical mice, how can one be small and another fat? Research on epigenetic changes resulting from the environment can give us clues into obesity in mice--and humans.

Scientists work with animal models to better understand type 2 diabetes to treat the disease. They have developed specialized animal models that mimic the condition.  One line of mice, known as KK mice, develop obesity and glucose intolerance that lead to type 2 diabetes. Another rodent model, the Zucker diabetic fatty rat, is bred to be a precise model of human type 2 diabetes.

In both cases, researchers found that ZIKV-177 reduced levels of Zika virus in pregnant mice and their fetuses, compared with pregnant mice that were not given the antibody.

Scientists announced Monday that they had created mice with small amounts of human brain cells in an effort to make realistic models of neurological disorders such as Parkinson's disease.

Researchers have designed a nanoparticle-based therapy that is effective in treating mice with multiple myeloma, a cancer of immune cells in the bone marrow.

WEDNESDAY, April 22, 2015 (HealthDay News) -- In a step toward personalized vaccines against cancer, scientists report they have developed an immune-system therapy that knocks out several types of aggressive tumors in mice. German researchers said the findings, reported April 22 in the journal Nature, could lead to a "blueprint" for developing tailored vaccines for a range of cancers. Such vaccines would be designed for individual patients, based on the specific genetic mutations in their tumors.

Researchers at the University of Pennsylvania performed "stress tests" on pregnant mice using a predator's odor, restraint, or unfamiliar noises. After the mice gave birth, the scientists analyzed the bacterial communities in their vaginas and in their pups' colons. The researchers found that stress during pregnancy altered the expression levels of several proteins involved in vaginal immunity and the frequency of Lactobacillus bacteria, which, expectedly, correlated to lower frequencies of Lactobacillus within their pups' gut microbiomes. Male pups of stressed mothers also displayed an increase in anaerobic bacteria like Clostridium and Bacteroidesin.

SAN ANTONIO -- Scientists at a South Texas research center made a breakthrough discovery by destroying the Ebola virus in animals through a Chinese herb. Texas Biomedical Research Center said a compound derived from the herb called tetrandrine was used to make a drug. He says his team injected mice with the drug.

Immune cells in mice with lupus symptoms have overactive metabolisms, so scientists inhibited two metabolic pathways and succeeded in reversing lupus symptoms in mice