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The groundwater is cold, deep and twice as salty as seawater, but the water streaming out of Blood Falls, which teems with microbes, tells us that it is unlikely to be lifeless. "The fact that the [water] contains metabolically active micro-organisms that appear to be suited to life in a dark, cold brine supports the idea that life should persist throughout the subsurface," says Mikucki. If so, those microbes could be fuelling life in the Southern Ocean. By breaking down iron-containing rocks they might be dumping as much as 170 million kilograms of iron into the ocean each year, according to the researchers' estimates, helping to explain why marine productivity is seasonally very high near to the coast.

The test, dubbed VirScan, and research surrounding it is the subject of a new report published in the journal Science. For the study, scientists screened sera, a part of the blood, from 569 people in the U.S., South Africa, Thailand, and Peru and tested for more than 200 types of viruses.

An exciting new test might help us save antibiotics. Needing only a drop of blood, researchers at Duke have developed a rapid assay that can tell viral infections-which generally can't be treated-from bacterial ones that may benefit from antibiotics. While I don't usually write about drugs or products in development, this test piqued my interest and left me excited about its potential to help contain antibiotic overuse.

A microbe that causes malaria tricks mosquitos into helping it spread, a new study finds. The microbe is a parasite that leaves a chemical behind in the blood of the people or other animals that it infects. Mosquitoes are drawn to scent of blood hosting this chemical. It entices them to slurp up some of the infected meal. Then voila! The parasites get airlifted from their old host to new ones. And so malaria spreads.

The idea of a general, quick and simple blood test for a diverse range of cancers just came closer to reality with news of a new study published in Nature Medicine.

Using a patient's own stem cells, researchers have corrected the genetic alteration that causes sickle cell disease, a painful, disabling inherited blood disorder that affects mostly African-Americans. The corrected stem cells were coaxed into immature red blood cells in a test tube that then turned on a normal version of the gene

The researchers' approach to developing the method was adopted from food science, where it is used for control of complex industrial processes. Basically, it involves handling and analysing huge amounts of biological data in a holistic and explorative way. The researchers analysed all compounds a blood sample contains instead of - as is often done in health and medical science - examining what a single biomarker means in relation to a specific disease. "When a huge amount of relevant measurements from many individuals is used to assess health risks - here breast cancer - it creates very high quality information. The more measurements our analyses contain, the better the model handles complex problems," continued Professor Rasmus Bro.

In a new study, researchers have made insights into how the blood-brain barrier, or BBB, is maintained, identifying a protein key to the process. Delivering this protein to mice with the rodent equivalent of MS improved their symptoms.

The question of cell renewal is one that all of us have intuitive daily experience with. We all notice that our hair falls out regularly, yet we don't get bald (at least not until males reach a certain age!).  Similarly, we have all had the experience of cutting ourselves only to see how new cells replaced their damaged predecessors. And we donate blood or give blood samples without gradually draining our circulatory system. All of these examples point to a replacement rate of cells, that is characteristic of different tissues and in different conditions, but which makes it abundantly clear that for many cell types renewal is a part of their story.

1:20 video on blood clotting 

But this tiny sample turned out to hold tremendous scientific value. It was from a person fortunate to survive the deadly Ebola virus outbreak of 2014. Walker and her colleagues wanted to know if they could identify some special antibodies in that person's blood. If this person had special Ebola-neutralizing antibodies, that might help explain why that person lived. The antibodies might also help provide a template for future development of a vaccine. Or, they could be the basis for genetically engineered copies that could be manufactured at large scale, stockpiled and used to rescue people newly infected in an outbreak.

HIV is a disease of the gut, a concept that's easy to lose sight of with all the attention paid to sexual transmission and blood measurements of the virus and the CD4+ T cells it infects and kills. But the bottom line is that about two thirds of all T cells reside in the lymphoid tissue of the gut, where the virus spreads after exposure, even before it shows up in blood.

First, surgeons remove the uterus and part of the vagina from the donor - in this case, one who was deceased, since it is a risky surgery that involves separating uterine blood vessels that are tightly wrapped around the tubes from the bladder. Next, the uterus is transferred to the living recipient. Surgeons connect an artery and a vein on either side of the uterus to connect it to the recipient's blood supply. A piece of the donor's vaginal tissue is attached to the recipient's vagina, and supporting tissue is attached to the pelvis to secure the organ in place. It's not necessary to connect any nerves.

animation of agglutination

The Aedes aegypti mosquito is the major vector for transmission of numerous viral diseases, including yellow fever, dengue, and now, Zika. Interestingly, different subspecies of A. aegypti are known to exist in close proximity but with considerable genetic divergence between them. One major difference between a "forest" form and a "domestic" form is a strong preference in the latter subspecies for human over non-human blood biting. This difference was explored with genetic and neurophysiological approaches by a research group at Rockefeller University and published in a 2014 paper in Nature. This flipped case study uses parts of the Nature paper to focus on elements of the scientific method as well as evolutionary questions raised by the difference in biting preference between the two subspecies. Students prepare for class by watching a video that provides background information about the published study that forms the basis for the case. In class students then work in groups to develop a hypothesis, predictions and proposed experiments to test the idea of different biting preferences.

Virtual blood typing lab

An elderly woman living independently with some help from her family is brought to the local emergency room because she is confused and vomiting. While her son suspects a stroke, a quick battery of laboratory tests indicates that her current problems are the result of impaired kidney function, an old-fashioned home remedy for ulcers, and her prescribed blood pressure medication. The combination of patient- and drug-related factors produces an acid-base disorder responsible for her confusion. This disorder further disrupts her kidney function. The case illustrates secretion and reabsorption processes in the kidney tubule which regulate plasma and urinary electrolytes (including calcium) and pH. The role of bicarbonate in maintaining systemic pH is emphasized. Interactions among the renal, respiratory and nervous systems in the regulation of systemic pH are also illustrated. Further, basic principles of pharmacotherapy and issues related to the appropriate use of medications are introduced. The case was developed for use in a physiology or human anatomy and physiology course, but it might be used in undergraduate nursing courses as well (e.g., pharmacology, pathophysiology).

3 min video, Scientists have made a major advancement in the world of cloning-- creating hundreds of identical mice from a single drop of blood. The implications are pretty big. Why? Anthony Carboni as the answers.

Can't remember every viral infection you've ever had? Don't worry, your blood can. A new test surveys the antibodies present in a person's bloodstream to reveal a history of the viruses they've been infected with throughout their life. The method could be useful not only for diagnosing current and past illnesses, but for developing vaccines and studying links between viruses and chronic disease.

These case studies heralded a new appreciation for the phenomenon of genetic chimerism-when an individual carries two or more genetically distinct cell lines in different parts of her body. Until the advent of techniques for blood typing and karyotyping cells, genetic chimeras where thought to be very rare. They only came to light when the phenotypes associated with the two distinct genomes were so discordant that the resulting individual was clearly exceptional, with patches of distinct skin coloration throughout the body, for example, or hermaphroditic genitals. In reality, genetic chimeras may be quite common, disguised in perfectly normal bodies harboring genetically distinct cell lineages.