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67 percent more neurons in their prefrontal cortex (PFC) than typical children

executive functions"—high-level thinking, such as planning ahead, inhibiting impulses and directing attention.

In brain tissue from both autistic children and autistic adults, genes coding for proteins that identify and repair mistakes in DNA were expressed at unusually low levels. Additionally, all autistic brains demonstrated unusual activity levels for genes that determine when neurons grow and die and how newborn neurons migrate during early development

Some genes involved in immune responses, cell-to-cell communication and tissue repair, however, were expressed at unusual levels in adult autistic brains, but not in autistic children's brains

autistic child develops in the womb, something—an inherited mutation or an environmental factor like a virus, toxin or hormone—muffles the expression of genes coding for proteins that usually fix mistakes in sequences of DNA

Errors accumulate.

The genetic systems controlling the growth of new neurons go haywire, and brain cells divide much more frequently than usual, accounting for the excess neurons found in the PFC of autistic children.

autistic brain grow physically larger and form more connections than in a typical child's brain.

immune system reacts against the brain's overzealous growth,

Not all researchers, however, accept

If scientists definitively link autism to a characteristic sequence of changes in gene expression and unusual neural growth, then it becomes possible to target and reverse any one of the thousands of steps in that sequence.

cloned the receptor and used this to genetically engineer human blood stem cells.

mature T cells that can attack HIV in tissues where the virus resides and replicates.

CD4 cells are white blood cells that are an important component of the immune system, helping to fight off infections.

CD4 "helper" T cells

engineering stem cells to form immune cells that target HIV is effective in suppressing the virus in living tissues in an animal model

increased

HIV in the blood decreased.

The engineered stem cells developed into a large population of mature, multi-functional HIV-specific CD8 cells that could specifically target cells containing HIV proteins. The researchers also discovered that HIV-specific T cell receptors have to be matched to an individual in much the same way an organ is matched to a transplant patient.

Expanding on previous research providing proof-of-principle that human stem cells can be genetically engineered into HIV-fighting cells

In this current study, the researchers similarly engineered human blood stem cells and found that they can form mature T cells that can attack HIV in tissues where the virus resides and replicates. They did so by using a surrogate model, the humanized mouse, in which HIV infection closely resembles the disease and its progression in humans.

increased, while levels of HIV in the blood decreased. CD4 cells are white blood cells that are an important component of the immune system, helping to fight off infections. These results indicated that the engineered cells were capable of developing and migrating to the organs to fight infection there.

athletic frogs tended to have faster-changing genomes.

During exercise, the circulatory system provides blood and oxygen to the tissues that are needed most

When physical activity has stopped, the rush of blood and oxygen when circulation is restored to those tissues produces a burst of free radicals that can cause wear and tear on DNA, eventually causing genetic changes that -- if they affect the DNA of cells that make eggs or sperm -- can be passed to future generations.

the offspring of parents who experience famine are at heightened risk for developing schizophrenia, some research suggests — perhaps because of the chemical signatures on the genes that parents pass on.

in some people with autism, epigenetic markers had silenced the gene which makes the receptor for the hormone oxytocin. Oxytocin oils the brain’s social circuits, and is critical in cementing relationships; a brain short on receptors for it would most likely struggle in social situations.

In one large study of people with schizophrenia, researchers at Johns Hopkins are analyzing blood and other data to see whether the degree of epigenetic variation is related to the inherited risk of developing the disorder. In another, researchers at Tufts are studying the genes of animals dependent on opiates to see how epigenetic alterations caused by drug exposure affect the opiate sensitivity of the animals’ offspring.

most protein reconfigurations occur in nanoseconds

In research on proteins, it was assumed (given their chemical composition) proteins would uniformly fold as they cool down and unfold as they heat up. (Think of a balloon expanding and shrinking with the temperature of the air inside.) The experiments didn’t bear this out; the rate of folding or unfolding according to temperature change was unequal (asymmetric) and uneven (nonlinear).

In recent biochemistry a great deal of work is done with ‘tagging’ or ‘marking’ molecules with fluorescent and phosphorescent materials. It’s well known that fluorescence and phosphorescence are phenomena closely related to protein folding and they can only be understood in terms of quantum transition between molecules.

With a quantum transition, the protein could change configuration by ‘jumping’ – skipping all the transition steps – to the final configuration. They call this quantum folding and they developed a mathematical model that shows how the folding, which is virtually instantaneous, would react to change in temperature.

Their quantum transition model matched the folding curves for 15 different proteins and also provides an explanation for the different rates of folding and unfolding among these proteins.

Luo and Lu’s paper is short, a mere 16 pdf pages, and the model is unpretentious mathematically. (Luo has several other related papers on arXiv.) It comes from unknown researchers in an unknown corner of the academic world, and it’s published on the open-source arXiv system. The lack of pedigree means that it will take more time than usual for scientists around the world to learn of it, examine it, and possibly test it.

“We developed a method to detect proteins whose molecular evolution correlates with longevity of a species. The proteins we detected changed in a particular pattern, suggesting that evolution of these proteins was not by accident, but rather by design to cope with the biological processes impacted by ageing, such as DNA damage. The results suggest that long-lived animals were able to optimise bodily repair which will help them fend off the ageing process.”