Every week, a large number of scientific studies have been published. Here's a look at some of the more interesting ones.
Understand the mechanism of reduced blood flow to the brain of Alzheimer's
It is well understood that there is decreased blood flow to the brain of Alzheimer's patients. But why that was not well understood. However, a research group with University College London found that it may be due to reaching cells that are wrapped around blood vessels versus, which can reduce blood supply by half.
The cells involved are pericytes, which are packaged in capillaries and have the ability to contract and regulate blood flow. Looking at the capillaries of Alzheimer's affected human brain tissue and in mice raised to develop Alzheimer's, they found that the capillaries were pressed by pericytes. And since they used amyloid beta, a brain brain accumulation in Alzheimer's patients became the healthy brain tissue, the capillaries pressed.
"Our study has for the first time identified the underlying mechanisms behind the reduction of brain blood flow in Alzheimer's disease," said lead author Ross Nortley . "As reduced blood flow is the first clinically detectable sign of Alzheimer's, our research generates new leaders for possible treatments in the early stage of the disease."
• Cannabinoid as an antibiotic?
Cannabinoid is the primary non-psychoactive chemical in cannabis and hemp. It has been approved by the US Food and Drug Administration (FDA) for some form of epilepsy and is being studied for a variety of other medical conditions. Researchers found that is active against Gram-positive bacteria including those behind Staphylococcus aureus and Streptococcus pneumoniae with strength similar to antibiotics vancomycin or daptomycin.
• Swimming in Ocean Alters Skin Microbiome
Research in the microbiome – the trillions of bacteria, viruses and fungi living in and on the body – intensifies and finds essential for a variety of diseases, not just gastrointestinal diseases. Scientists recently found that swimming in the sea alters the skin's microbiome and is likely to increase the sensitivity of infection. The sea water seems to wash away normal skin microbiome and replace it with ocean bacteria.
• Why checkpoint inhibitors sometimes do not work
Researchers at University of Colorado Cancer Center published research ] in journal Cancer Immunology Research that provides deeper insight in why sometimes checkpoint inhibitors do not work. Tumors have a surface protein called PD-L1. T cells, a type of immune cell, have a surface protein called PD1. Tumor cells use PD-L1 to essentially trigger PD1 to tell T cells to leave them alone. Checkpoint inhibitors work by blocking the function of either PD-L1 (Keytruda, for example) or PD1 (Bristol-Myers Squibb's Opdivo).
Another group of proteins is called the large histocompatibility complex (MHC). MHC proteins transport antigens from within a cell and move them to the cell surface so that they can be "seen" by T cells. And when T cells recognize a dangerous antigen on an MHC protein, they attack the cell unless the T cell is deactivated by the PD1 / PD-L1 interaction. However, if a cancer cell does not have MHC proteins, there is no PD1 / PD-L1 interaction because the cancer cell does not present any antigens to the immune system.
• Human centromers retain DNA from neanderthals and other ancient people
Centromers anchor chromosomes when the cells are divided. When observing under a microscope, the centromer looks like a squeezed part of the chromosome. Centromers, however, do not participate much in crossover events that allow evolutionary activity. Researchers analyzed centromeric DNA and found that it contained material from neanderthal DNA in non-African genomes as well as ancient African genomes.
• Even More Data Compounds The immune system response to Alzheimer's disease research suggests that although the accumulation of amyloid and tau proteins is involved in Alzheimer's disease, it is actually an immune response to that which causes damage to brain tissue. which results in memory loss and confusion. Researchers at Washington University School of Medicine in St. Louis has added that theory suggesting that these brain immune cells, microglia, appear to damage nearby cells when they are not functioning properly.