In the spirit of Halloween we bring you the science fact and fiction behind the undead. Zombies, those brain loving little guys, (and girls) are everywhere. Sure, we are all familiar with the classic zombie, but did you know that we aren’t the only zombie lovers out there? It turns out that nature has its own special types of zombies, but this isn’t a science fiction movie, this is science fact! Sometimes fact can be scarier than fiction, so let’s dive in.
The development of antiretroviral therapy, a combination of drugs that slows the replication of HIV in the body, has transformed the treatment of this infection. What was once a certain death sentence is now a chronic condition that people can live with for decades. But this therapy has drawbacks. There are side effects, including kidney problems, decreased bone density, and gastrointestinal problems. And if a person discontinues his or her treatment, even missing a few doses, the level of the virus in the body is able to rebound quickly.
Viruses that infect bacteria are among the most abundant life forms on Earth. Indeed, our oceans, soils and potentially even our bodies would be overrun with bacteria were it not for bacteria-eating viruses, called bacteriophages, that keep the microbial balance of ecological niches in check. Now, a new study suggests that bacteriophages made of RNA — a close chemical cousin of DNA — likely play a much larger role in shaping the bacterial makeup of worldwide habitats than previously recognized.
Think your DNA is all human? Think again. And a new discovery suggests it’s even less human than scientists previously thought. Nineteen new pieces of non-human DNA — left by viruses that first infected our ancestors hundreds of thousands of years ago — have just been found, lurking between our own genes.
In the microscopic life that thrives around coral reefs, researchers have discovered an interplay between viruses and microbes that defies conventional wisdom. As the density of microbes rises in an ecosystem, the number of viruses infecting those microbes rises with it. It has generally been assumed that this growing population of viruses, in turn, kills more and more microbes, keeping the microbial population in check. It’s a model known as “kill-the-winner” — the winners being the blooming microbial cells and the killers being the viruses (mostly bacteria-killing viruses known as bacteriophages) that infect them.
The Zika virus infects a type of neural stem cell that gives rise to the brain’s cerebral cortex, Johns Hopkins and Florida State researchers have found. On laboratory dishes, these stem cells were found to be havens for viral reproduction, resulting in cell death and/or disruption of cell growth. While this study does not prove the direct link between Zika and microcephaly, it does pinpoint where the virus may be doing the most damage.
Viruses are molecular thieves that take from their hosts under the cloak of darkness. But now a Virginia Tech scientist has found a way to not only track viral hijackers, but also potentially stop them from replicating. The discovery has broad ranging applications in stopping viral outbreaks such as Hepatitis C in humans and a number of viruses in plants and animals because it applies to many viruses in the largest category of viral classes — positive-strand RNA viruses.
Bacteriophages are viruses that infect and kill bacteria. The name originates from the Greek ‘phagos’ which means ‘to devour’. Bacteriophages were discovered 100 years ago because of their ability to replicate in a pathogenic bacterium, kill it and thereby cure the patient. As a small spaceship landing on the moon, the microscopic particles land on the surface of the bacteria where they inject their deadly genetic material.
Want to make a virus? It’s easy: combine one molecule of genomic nucleic acid, either DNA or RNA, and a handful of proteins, shake, and in a fraction of a second you’ll have a fully-formed virus. While that may sound like the worst infomercial ever, in many cases making a virus really is that simple. Viruses such as influenza spread so effectively, and as a result can be so deadly to their hosts, because of their ability to spontaneously self-assemble in large numbers.
For years, researchers have noted a tantalizing link between some neurologic conditions and certain species of the herpes virus. In patients with Alzheimer’s disease, multiple sclerosis, and cerebellar ataxia, among other neuropathies, the cerebrospinal fluid teems with Epstein-Barr virus (EBV). Yet, the nature of that link has remained unclear, as it has been assumed that EBV, as well as other viruses in the same sub-family, called gammaherpesviruses, cannot infect neurons.
Nearly 37 million people worldwide are living with HIV. When the virus destroys so many immune cells that the body can’t fight off infection, AIDS will develop. The disease took the lives of more than a million people last year.
Researchers at Case Western Reserve University and the University of Michigan have produced the first image of an important human protein as it binds with ribonucleic acid (RNA), a discovery that could offer clues to how some viruses, including HIV, control expression of their genetic material. That information could lead to new strategies to block viruses from replicating, thereby limiting or halting infection.
When dealing with bacteria, antibiotics are usually the frontrunner, but there are cases where antibiotics are a big no. Take baby formula for instance, we cannot use antibiotics to keep bacteria at bay. This has posed a safety problem in recent years, but researchers have shown that we can use a natural enemy of bacteria to fight back without risk to infants’ health.
In the spirit of Halloween we bring you the science fact and fiction behind the undead. Zombies, those brain loving little guys, (and girls) are everywhere. We are all familiar (if you are horror fans, or at least not living on an Amish compound) with the classic zombie. But did you know that we aren’t the only zombie lovers out there? It turns out that nature has its own special types of zombies, but this isn’t a science fiction movie, this is science fact!
Classifying something as living isn’t as easy as it sounds, after all we are all atoms, so when do atoms go from nonliving to living? Despite the complexities of viruses, we have historically deemed them nonliving. However, a new analysis supports the hypothesis that viruses are living entities that share a long evolutionary history with cells. The study offers the first reliable method for tracing viral evolution back to a time when neither viruses nor cells existed in the forms recognized today.
Proteins called broadly neutralizing antibodies (bNAbs) are a promising key to the prevention of infection by HIV, the virus that causes AIDS. bNAbs have been found in blood samples from some HIV patients whose immune systems can naturally control the infection. These antibodies may protect a patient’s healthy cells by recognizing a protein called the envelope spike, present on the surface of all HIV strains and inhibiting, or neutralizing, the effects of the virus. Now Caltech researchers have discovered that one particular bNAb may be able to recognize this signature protein, even as it takes on different conformations during infection–making it easier to detect and neutralize the viruses in an infected patient.
Researchers have revealed that HIV does not cause AIDS by the virus’s direct effect on the host’s immune cells, but rather through the cells’ lethal influence on one another. HIV can either be spread through free-floating virus that directly infect the host immune cells or an infected cell can pass the virus to an uninfected cell.
Disease-causing viruses engage their hosts in ongoing arms races: positive selection for antiviral genes increases host fitness and survival, and viruses in turn select for mutations that counteract the antiviral host factors. Studying such adaptive mutations can provide insights into the distant history of host-virus interactions. A study of antiviral gene sequences in African monkeys suggests that lentiviruses closely related to HIV have infected primates in Africa as far back as 16 million years.
Researchers have devised an entirely new approach to vaccines – creating immunity without vaccination. The team has demonstrated that animals injected with synthetic DNA engineered to encode a specific neutralizing antibody against the dengue virus were capable of producing the exact antibodies necessary to protect against disease, without the need for standard antigen-based vaccination. Importantly, this approach, termed DMAb, was rapid, protecting animals within a week of administration.
Scientific experiments with the herpes virus such as the one that causes Marek’s disease in poultry have confirmed, for the first time, the highly controversial theory that some vaccines could allow more-virulent versions of a virus to survive, putting unvaccinated individuals at greater risk of severe illness. The research has important implications for food-chain security and food-chain economics, as well as for other diseases that affect humans and agricultural animals.
Flu vaccines can be something of a shot in the dark. Not only must they be given yearly, there’s no guarantee the strains against which they protect will be the ones circulating once the season arrives. New research by Rockefeller University scientists suggests it may be possible to harness a previously unknown mechanism within the immune system to create more effective and efficient vaccines against this ever-mutating virus.
The 2014-2015 flu vaccine didn’t work as well compared to previous years because the H3N2 virus recently acquired a mutation that concealed the infection from the immune system. A new study reveals the major viral mutation responsible for the mismatch between the vaccine strain and circulating strains. The research will help guide the selection of viral strains for future seasonal flu vaccines.
The fight against HIV is ongoing and despite our rapid progression against the disease we still lack a cure or even adequate treatment for people infected. However, new research suggests that cloaking immune cells with antibodies that block T cell trafficking to the gut can substantially reduce the risk of viral transmission, at least in a non-human primate model of HIV infection. If it works out, this could help slow down the spread of HIV and give people a better shot at a normal life.
You know how some zombie movies start with a discovery of a virus, it gets loose, and things quickly spiral out of control from that? Well in breaking news a team of researchers have found two 700-year-old viral sequences in frozen caribou dung in an arctic ice patch. The group isolated part of a viral RNA genome and the complete genome of a DNA virus. Then they infected living plants with the DNA virus, what could go wrong?