Matthias Gunzer and colleagues imaged mouse shinbones and found hundreds of tiny capillaries crossing the hard outer shell of the bone.
Skyscale of Blood
The authors calculated that most of the blood passing through bones flows through TCVs. In addition, the authors found similar, if thicker, canals in human long bones, although whether they are also TCVs remains to be confirmed.
The authors also directly observed immune cells migrating through TCVs, which may provide a shortcut between the bone marrow and inflammation sites. It's common knowledge that leaves turn yellow and orange in the fall and winter. These colors are actually in the leaves the entire year, but are only visible once trees stop making chlorophyll when the weather gets cold.
Red leaves, however, are another story. The red comes from anthocyanin, the same pigment that makes flowers red. Trees begin to produce anthocyanins in the fall, when it acts as an antifreeze to protect the leaves from the cold. But like its yellow and orange brethren, these red leaves eventually fall to the ground.
It's truly a mystery why some trees, such as red maples, spend so much energy making anthocyanins in leaves that will soon die, Live Science previously reported. Red tides are the bane of any beachgoer, because it means swimmers can't safely go into the water.
The Nature of Blood Background
These tides occur when certain types of algae have a population boom. Millions of algae can change the color of the water, often to a rusty red. Algae blooms can deplete nitrates and phosphates in the water, leading to an imbalance in marine- nutrient cycles and the animals dependent on them, Live Science previously reported. The blooms can also release toxins into the water , affecting marine life and swimmers. Three common variants in the gene MC1R give redheads their distinctive red hair, Live Science previously reported. But red hair is recessive, so a child must get these variants from both parents in order to sport red locks.
Some Neanderthals — the closest extinct relative of modern humans — also had red hair.
But the gene variant that gave them the red hue is different than the one found in people today, Live Science previously reported. The mountains in China's Zhangye National Geopark shown here are dramatically red. Blood is the epicentre of much biomedical research, from fighting disease to creating artificial substitutes for this vital fluid. This Outlook discusses topics including a gene-editing treatment for sickle-cell disease and keeping the blood supply safe from pathogens such as Zika virus. For more on blood from nature.
Outlook 27 Sep Nature.
Diasporas and Desperations
Technological advances are creating an explosion in possibilities for the blood-based diagnosis of brain injuries, infections and cancers. When threats emerge to the blood supply, public-health officials must make difficult decisions to reduce the risk of infections being transmitted by transfusions. The ability to give donated blood to patients has saved countless lives.
source link But the routine nature of such transfusions is being rethought. Bloodstain pattern analysis is used by forensic scientists to help reconstruct violent crimes. Efforts are underway to root the often subjective practice in science.
Reds in nature
Alzheimer's disease and ageing brains could benefit from therapies based on blood's liquid component. Clinical trials may soon test whether gene editing can cure a group of debilitating haemoglobin disorders. Article 7 Nov Nature.
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- Disorders of the Human Adrenal Cortex!
Haematopoietic stem and progenitor cell conversion of human pluripotent stem cell-derived haemogenic endothelium.