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The article presents an analysis of how to rear children. After a long day spent chasing after their small children, many exhausted parents may feel like they are raising monkeys. But while kids may act like the fellow primates, they do not grow like them. Unlike monkeys, humans stay relatively small during childhood and then experience a growth spurt during adolescence. A new study suggests that this strategy may help increase the number of offspring parents can successfully rear. Anthropologists Michael Gurven of the University of California, Santa Barbara, and Robert Walker of the University of New Mexico in Albuquerque tested an idea by studying two hunter-gatherer societies who forage for food much like early humans are believed to have done.

This article presents information on a study related to tuberculosis. This study indicates that the disease has been around for as long as 3 million years, making it 100 times older than previously thought. Tuberculosis, an infectious disease that damages the lungs and kills approximately 2 million people each year, is caused by thousands of extremely closely related strains of bacteria collectively known as the Mycobacterium tuberculosis complex (MTBC). In an effort to reunite the MTBC with its extended family, M. Cristina Gutierrez of the Institut Pasteur in Paris and colleagues analyzed tuberculosis bacteria from patients in eastern Africa.

The article cites a study, conducted by Craig Rubens and colleagues of Children's Hospital in Seattle, Washington, which used a new strategy to develop a vaccine that protects mice from multiple variants of the Group B streptococcus (GBS), which kills around 100 newborns in the U.S. each year. GBS bacteria live in the genital tracts of about a quarter of healthy women. Those infected experience few problems, but their children can develop sepsis, meningitis, or pneumonia if they contract the bug during birth. To make the new vaccine, the researchers first sequenced the complete genome of eight GBS strains. Then a computer program identified 589 proteins likely to be on the surface of the bacterium, where they could be detected by the immune system.

The article highlights some new findings related to the prion hypothesis, according to which, the disease-causing protein PrP[sup Sc] makes copies of itself inside the brain, multiplying until it forms fibers that destroy neurons and eventually kill the animal. According to a study, rogue proteins are responsible for a host of fatal neurological diseases, including Mad Cow Disease and scrapie. In the first round of the study, researchers mixed ground up healthy brain with brain material from a scrapie-infected animal.

The article presents information on a study conducted by physiologist Claudius Griesinger of University College London and colleagues, which focuses on the science of speedy hearing. Interpreting the cadences of human speech requires that information be transmitted from the ear to the brain with exquisitely precise timing. Neurons in general are no slackers at transmitting signals, but specialized neurons in the ear known as inner hair cells perform at an even higher level. Upon stimulation, the vesicles fuse with the outer membrane of the neuron and release neurotransmitters that excite the next neuron in line.

This article reports that Alexander Fleming's famous mold, Penicillium notatum, didn't make much of the antibiotic, and industry turned to alternate strains to ramp up production. A new report shows that a single enzymatic mutation made all the difference. Scientists employed P. notatum during early attempts to manufacture penicillin, but they later abandoned it favor of a more promising species of mold, P. chrysogenum, discovered on a cantaloupe in 1943. The key difference was how the strains metabolize phenylacetic acid (PA), a precursor of penicillin. Mold can convert PA into either penicillin or 2-hydroxy-PA, a product formed by the enzyme expressed from a gene called pahA .

The article reports that a polio vaccine produced by at least one eastern European manufacturer was contaminated with a potentially cancer-causing virus as late as 1978. Introduced in 1954, the polio vaccine was a public health breakthrough that brought the spread of the paralytic virus to a screeching halt. To produce enough polio virus to make vaccine, manufacturers grew the virus in the kidney cells of rhesus monkeys. To prevent future contamination, vaccine producers switched to growing polio virus in SV40-resistant African green monkeys instead of rhesus monkeys.

The article presents information about high-protein diets. Both humans and animals fed a diet heavy in protein eat less than those offered high-starch food. A study offers a possible explanation for this phenomenon. Motivated by the surge in the incidence of obesity and type II diabetes, researchers are working to understand the molecular pathways that control the sensations of hunger and fullness. When the researchers simulated intestinal production of glucose by injecting glucose directly into the portal vein, starch-fed rats ate less.