There’s finally some progress in the fight against Zika. A vaccine is being given to 160 people in Zika-hit Puerto Rico, and a preliminary study has identified two existing drugs that seem to protect human brain cells from the virus.
The vaccine, developed by Inovio Pharmaceuticals, contains a synthetic DNA fragment similar to one in the virus itself. The company hopes that people who receive it will develop immune protection against Zika.
The two drugs that might be useful as a treatment came from an analysis of thousands of compounds, including some drugs that are used to treat other conditions. Zika seems to target cells that make new neurons in the brain and stop them from working properly. This is thought to cause the horrendous brain defects seen in some babies born with the virus, and could also put infected adults at risk of memory and mood disorders.
A team of researchers from the US and China identified one drug – currently in clinical trials for liver diseases – that protects brain cells from damage, and 10 others that stop Zika from replicating, one of which is an already-approved drug used to treat worm infections. A combination of two compounds could be an effective Zika treatment, say the authors, who hope to start testing in animals soon.
But we are still some way off having treatments ready for use on the ground, says Edwin Trevathan, a paediatric neurologist at Vanderbilt University in Nashville, Tennessee, who advises the US Centers for Disease Control and Prevention (CDC) on Zika. “Even if the vaccine development moves as quickly as we’d like, realistically it will be a year before we have something we can use to protect people,” he says.
The development is welcome after a couple of weeks of bad news. Last Friday, the CDC described the first known case of Zika transmission from a man who had shown no symptoms of illness to his sexual partner, a couple of weeks after he returned from the Dominican Republic. The news came days after a finding that Zika had remained in an Italian man’s semen for six months after a trip to Haiti – around three times longer than previously seen in people.
At the same time, doctors and scientists are warning that the effects of Zika could be worse than thought, and may not affect some babies for several years, when it could impact their brain development. “It could affect parts of the brain that don’t manifest their function until the age of 2, 4 or 6,” says Travathan. “Sadly, I suspect that many of us who take care of children will see the effects of Zika for a long time. This is a problem that may have been dramatically underestimated.”
Until we have vaccines and treatments, efforts are under way to stem infections and the spread of Zika-infected mosquitoes. Last Friday, the US Food and Drug Administration recommended testing for Zika virus in all donated blood before it is used. The organisation has also fast-tracked the approval of a commercially available Zika diagnosis kit.
Semen does more than fertilise eggs. In mice, it seems to prime the female’s immune system for pregnancy, making it more likely that an embryo will successfully implant in the womb. It appears to prompt similar changes in women, a finding that could explain why IVF is more successful if couples have regular sex during treatment.
Sarah Robertson at the University of Adelaide, Australia, and her colleagues found that each time a female mouse copulates, it caused the release of immune cells called regulatory T-cells, which are known to dampen down inflammation in the body.
Examining the cervix in women, the team found signs that semen does seem to prompt immune system changes in people too. Shortly after sex, they detected the cervix begins to release immune signalling molecules, which may be a sign of increased levels of regulatory T-cells.
“It’s as if the seminal fluid is a Trojan horse that activates the immune cells to get things ready for conception,” says Robertson.
As well as making the embryo more likely to successfully implant in the womb lining, it’s possible that such effects also minimise the chances of a woman’s body rejecting the fetus later on in pregnancy, she says. Women who conceive after limited sexual activity are more likely to develop disorders during pregnancy, she adds.
The findings, presented at the International Congress of Immunology in Australia this week, fit with observations that semen contains several signaling molecules – including cytokines, prostaglandins, and hormones – that can have an effect on female tissue.
The discovery has implications for IVF. After a woman’s eggs have been fertilised in the lab, an embryo is chosen for implantation and is surgically inserted into the womb. This is one of the points where IVF can fail, if an embryo is unable to implant in a woman’s uterine lining.
Many fertility clinics advise couples to abstain from sex during IVF treatment to minimise risk of infection from seminal fluid during the implantation surgery. This is a small risk outweighed by the benefits semen can have for the female immune system, Robertson says.
This is supported by a recent review of studies that concluded that sex during IVF improves embryo implantation rates by 23 per cent. “I think it’s really good for couples to know that there’s something they can do to help their chances – it allows them to take a bit of control back,” says Robertson.
Peter Illingworth of IVF Australia says the evidence is compelling. “I personally always say to IVF patients: ‘if you want to have sex, just have sex’.” But many couples choose not to during the treatment because IVF causes a lot of discomfort, he says. “If you’ve got ovaries the size of baseballs, sex is a much less appealing prospect.”
The effect of semen on a woman’s immune system could also help explain why most couples do not fall pregnant straight away, says Robertson. “In humans, it seems that at least three months of sexual cohabitation is required to give you the priming that you need,” she says.
If low levels of regulatory T-cells are for a cause of infertility, therapies that increase them may help women who have been trying unsuccessfully to get pregnant for a long time. Treatments like these are currently being developed for immune conditions like graft-versus-host disease, but they haven’t been tested for fertility yet.
“Our results suggest that the first-line approach to treating infertility should be to tell people to go home and practise,” Robertson says. “But if that doesn’t work, tackling regulatory T cells may be the way to go.”
Ecologists have discovered a food web beneath the waves of French Polynesia that is both unusual and spectacular.
A small channel hosts up to 700 sharks - far more than it can support based on the number of fish living there.
The predators survive by feasting every winter on huge numbers of grouper fish, which swim into the channel to spawn.
Those mobs of spawning fish concentrate prey from multiple reefs and the sharks lurk in the channel to take advantage of them, instead of hunting elsewhere.
The findings, published in the journal Current Biology, are an example of an "inverted trophic pyramid": the average biomass in the channel is skewed towards predators rather than prey.
It is only the convenient, seasonal meal delivery of spawning groupers into the Fakarava atoll's southern pass that sustains its rare concentration of gray reef sharks - the highest density of this species ever recorded.
Groupers gather in huge numbers to spawn during June and July / Laurent Ballesta
"We went there, in the beginning, to study the groupers, because we heard about these spawning aggregations that happen every year," said Dr Johann Mourier, who led the study for CRIOBE in French Polynesia but is now based at Macquarie University in Sydney.
"And we found this huge population of sharks. Up to 700 gray reef sharks - about two to three times higher density than found in any other reef, worldwide."
With colleagues from France and the US, Dr Mourier tagged and tracked 13 sharks using remote transmitters, to understand their behaviour; they also did regular surveys of the channel with underwater cameras and completed a census of different shark and fish species.
The team discovered that gray reef sharks in the channel, which is just 100m wide and 30m deep, fluctuated in number from about 250 in the summer to 700 in the winter.
That winter peak coincided with the spawning of the groupers, which brought together some 7,000 of the smaller fish at a time, from habitats up to 50km away.
"That's about 30 tonnes of fish; that's a big amount of food," Dr Mourier told BBC News.
Easy meal: spawning swarms of groupers deliver tonnes of food at a time / Andromede Oceanologie
The researchers witnessed the sharks taking aggressive advantage of this meal delivery, and also observed that the density of the sharks and the length of time they spent in the channel were significantly higher when the groupers were spawning.
It might sound incredibly convenient, but previous findings had suggested that when sharks live together in large groups like this - and risk tipping the balance of the trophic pyramid - they would simply travel further afield to find food.
"The idea was that sharks must make foraging excursions outside their area. They have to move to find food to survive," Dr Mourier explained.
"But in this case, we find that the spawning aggregations bring the food to them. They just can stay at the reef and save their energy."
The atoll of Fakarava, part of French Polynesia in the South Pacific, is a UNESCO biosphere reserve / Getty Images
The discovery has implications for conserving these species, he added. Laws to stop people fishing for sharks might not be enough to protect them - because huge spawning aggregations of fish are attractive to humans as well as to sharks.
"It's quite easy to catch your fish if they're in these huge aggregations - they're just concentrating on spawning," Dr Mourier said.
But overfishing those tempting crowds of fish could threaten the sharks themselves.
"Maybe that's why we don't find such shark densities in other reefs - because those spawning aggregations have been overfished."
The world is on track for its hottest year on record, the World Meteorological Organization says.
The world is on track for its hottest year on record and levels of carbon dioxide in the atmosphere have reached new highs, further fuelling global warming, the United Nations weather agency said Thursday.
June marked the 14th consecutive month of record heat for land and oceans, the World Meteorological Organization, WMO, said.
The average temperature in the first six months of 2016 was 1.3°Celsius (2.4°Fahrenheit) warmer than the pre-industrial era in the late 19th Century, according to NASA.
"This underlines more starkly than ever the need to approve and implement the Paris Agreement on climate change, and to speed up the shift to low carbon economies and renewable energy," said WMO Secretary-General Petteri Taalas.
Under December's Paris Agreement, nearly 200 governments agreed to limit global warming to "well below" 2°C (3.6°F) above pre-industrial times, while "pursuing efforts" for a ceiling of just 1.5°C. Temperatures are already nudging toward that lower limit.
"The heat has been especially pronounced in the Arctic, resulting in a very early onset of the annual melting of the Greenland ice sheet and Arctic sea ice," WMO said.
"What we’ve seen for the first six months of 2016 is really quite alarming," David Carlson, director of the WMO’s Climate Research Program, told a news briefing. "We would have thought it would take several years to warm up like this ... We don't have as much time as we thought."
The northern hemisphere, including the state of Alaska in the United States, Canada and Russia, have posted unusually warm temperatures, he said.
The last month with global temperatures below the 20th Century average was December 1984.
A strong El Nino weather event in the Pacific Ocean, a phenomenon associated with extreme droughts, storms and floods, "has now disappeared," the WMO said in a statement.
The El Nino event developed in 2015 and contributed to the record temperatures in the first half of 2016 before disappearing in May, WMO said.
"Climate change, caused by heat-trapping greenhouse gases, will not (disappear). This means we face more heat waves, more extreme rainfall and potential for higher impact tropical cyclones," said Taalas.
Women who have already passed through the menopause may be able to have children following a blood treatment usually used to heal wounds.
MENOPAUSE need not be the end of fertility. A team claims to have found a way to rejuvenate post-menopausal ovaries, enabling them to release fertile eggs, New Scientist can reveal.
The team says its technique has restarted periods in menopausal women, including one who had not menstruated in five years. If the results hold up to wider scrutiny, the technique may boost declining fertility in older women, allow women with early menopause to get pregnant, and help stave off the detrimental health effects of menopause.
“It offers a window of hope that menopausal women will be able to get pregnant using their own genetic material,” says Konstantinos Sfakianoudis, a gynaecologist at the Greek fertility clinic Genesis Athens.
“It is potentially quite exciting,” says Roger Sturmey at Hull York Medical School in the UK. “But it also opens up ethical questions over what the upper age limit of mothers should be.”
Women are thought to be born with all their eggs. Between puberty and the menopause, this number steadily dwindles, with fertility thought to peak in the early 20s. Around the age of 50, which is when menopause normally occurs, the ovaries stop releasing eggs – but most women are already largely infertile by this point, as ovulation becomes more infrequent in the run-up. The menopause comes all-too-soon for many women, says Sfakianoudis.
The age of motherhood is creeping up, and more women are having children in their 40s than ever before. But as more women delay pregnancy, many find themselves struggling to get pregnant. Women who hope to conceive later in life are increasingly turning to IVF and egg freezing, but neither are a reliable back-up option (see “The pregnancy pause“).
The menopause also comes early – before the age of 40 – for around 1 per cent of women, either because of a medical condition or certain cancer treatments, for example.
“It offers hope that menopausal women will be able to get pregnant using their own genetic material“
To turn back the fertility clock for women who have experienced early menopause, Sfakianoudis and his colleagues have turned to a blood treatment that is used to help wounds heal faster.
Platelet-rich plasma (PRP) is made by centrifuging a sample of a person’s blood to isolate growth factors – molecules that trigger the growth of tissue and blood vessels. It is widely used to speed the repair of damaged bones and muscles, although its effectiveness is unclear. The treatment may work by stimulating tissue regeneration.
Sfakianoudis’s team has found that PRP also seems to rejuvenate older ovaries, and presented some of their results at the European Society of Human Reproduction and Embryology annual meeting in Helsinki, Finland, this month. When they injected PRP into the ovaries of menopausal women, they say it restarted their menstrual cycles, and enabled them to collect and fertilise the eggs that were released.
“I had a patient whose menopause had established five years ago, at the age of 40,” says Sfakianoudis. Six months after the team injected PRP into her ovaries, she experienced her first period since menopause.
Sfakianoudis’s team has since been able to collect three eggs from this woman. The researchers say they have successfully fertilised two using her husband’s sperm. These embryos are now on ice – the team is waiting until there are at least three before implanting some in her uterus.
The team isn’t sure how this technique works, but it may be that the PRP stimulates stem cells. Some research suggests a small number of stem cells continue making new eggs throughout a woman’s life, but we don’t know much about these yet. It’s possible that growth factors encourage such stem cells to regenerate tissue and produce ovulation hormones. “It’s biologically plausible,” says Sturmey.
Sfakianoudis’s team says it has given PRP in this way to around 30 women between the ages of 46 and 49, all of whom want to have children. The researchers say they have managed to isolate and fertilise eggs from most of them.
“It seems to work in about two-thirds of cases,” says Sfakianoudis. “We see changes in biochemical patterns, a restoration of menses, and egg recruitment and fertilisation.” His team has yet to implant any embryos in post-menopausal women, but hopes to do so in the coming months.
PRP has already been helpful for pregnancy in another group of women, says Sfakianoudis. Around 10 per cent of women who seek fertility treatment at his clinic have a uterus that embryos find difficult to attach to – whether due to cysts, scarring from miscarriages or having a thin uterine lining. “They are the most difficult to treat,” says Sfakianoudis.
But after injecting PRP into the uteruses of six women who had had multiple miscarriages and failed IVF attempts, three became pregnant through IVF. “They are now in their second trimester,” says Sfakianoudis.
Fertility aside, the technique could also be desirable for women who aren’t trying to conceive. The hormonal changes that trigger menopause can also make the heart, skin and bones more vulnerable to ageing and disease, while hot flushes can be very unpleasant. Many women are reluctant to take hormone replacement therapy to reduce these because of its link with breast cancer. Rejuvenating the ovaries with PRP could provide an alternative way to boost the supply of youthful hormones, delaying menopause symptoms.
More eggs, pleaseSteve Gschmeissner/SPL
However, Sfakianoudis’s team hasn’t yet published any of its findings. “We need larger studies before we can know for sure how effective the treatment is,” says Sfakianoudis.
“One woman had been in menopause for 5 years. Six months after treatment, she had a period“
Some have raised concerns about the safety and efficacy of the procedure, saying the team should have tested the approach in animals first. “This experiment would not have been allowed to take place in the UK,” says Sturmey. “The researchers need to do some more work to make sure that the resulting eggs are OK,” says Adam Balen at the British Fertility Society.
To know if the technique really does improve fertility, the team will also need to carry out randomised trials, in which a control group isn’t given PRP.
Virginia Bolton, an embryologist at Guy’s and St Thomas’ Hospital in London, is also sceptical. “It is dangerous to get excited about something before you have sufficient evidence it works,” she says. New techniques often find their way into the fertility clinic without strong evidence, thanks to huge demand from people who are often willing to spend their life savings to have a child, she says.
If the technique does hold up under further investigation, it could raise ethical questions over the upper age limits of pregnancy – and whether there should be any. “I lay awake last night turning this over in my mind,” says Sturmey. “Where would the line be drawn?”
Health issues like gestational diabetes, pre-eclampsia and miscarriage are all more common in older women. “It would require a big debate,” says Sturmey.
How are the little swimmers doing? Low sperm counts or poor sperm quality are behind around a third of cases of couples who can’t conceive. A visit to a clinic for a test can be awkward, but a smartphone-based system lets men determine whether that’s necessary by checking their fertility at home.
Men often find it embarrassing to give a semen sample at a clinic, says Yoshitomo Kobori at the Dokkyo Medical University Koshigaya Hospital in Japan. So Kobori devised an alternative. “I thought a smartphone microscope could be an easy way to look at problems with male fertility,” he says.
Kobori and his colleagues came up with a lens less than a millimetre thick that can be slotted into a plastic “jacket”. Clipped on to the camera of a smartphone, it magnifies an image by 555 times – perfect for looking at sperm.
To do a home test, a man would apply a small amount of semen to a plastic sheet around five minutes after ejaculation and press it against the microscope.
Watch them swim
The phone’s camera can then take a 3-second video clip of the sperm. When viewed enlarged on a computer screen, it is easy for someone to count the total number of sperm and the number that are moving – key indicators of fertility.
Kobori says the system works as well as the software used in fertility clinics. When the team ran 50 samples through both systems, they got almost identical results. The work was presented at the European Society of Human Reproduction and Embryology meeting in Helsinki this month.
The system can’t assess the ability of sperm to fertilise an egg. “This method is only the simple version of semen analysis,” says Kobori. But that could be enough for men to identify potential fertility problems, and decide whether to seek help from a doctor.
The thread could be sewn into organs, wounds or orthopedic implants.
BOSTON, July 18 (UPI) -- The next time you have surgery, you may get sewn up with "smart" stitches.
Researchers at Tufts University have developed a new type of surgical thread capable of gathering diagnostic data and communicating it wirelessly in real time.
The development process allows scientists to integrate nano-scale sensors, electronics and microfluidics into a range of thread types -- something as basic as cotton or as complex as synthetics.
Once dipped in a series of sensory chemicals, the threads can measure the pressure, stress, strain and temperature inside a region of tissue. The smart threads can also measure pH and glucose levels. Such data can help doctors keep tabs on the healing process and alert caretakers to the early signs of infection.
The thread could be sewn into organs, wounds or orthopedic implants. The thread has yet to be tested in human patients, but it has revealed its potential in lab rats and test tube experiments.
Still, more research is needed to ensure the threads' biocompatibility.
"The ability to suture a thread-based diagnostic device intimately in a tissue or organ environment in three dimensions adds a unique feature that is not available with other flexible diagnostic platforms," researcher Sameer Sonkusale, director of the interdisciplinary Nano Lab at Tufts' School of Engineering, said in a news release. "We think thread-based devices could potentially be used as smart sutures for surgical implants, smart bandages to monitor wound healing, or integrated with textile or fabric as personalized health monitors and point-of-care diagnostics."
Cuba's Biotechnology Industry Group and BioCubaFarma are researching the potential of new vaccines, including a quadrivalent formula for dengue.
Institutions affiliated with Cuba's Biotechnology Industry Group and BioCubaFarma are working on the search for new vaccines, with some showing positive signs of security and effectiveness in preclinical and clinical trials.
A promising 7-valent conjugate vaccine to protect against pneumococcus is being studied by specialists at the Molecular Chemistry Center; along with several against tuberculosis, whose principal researchers are based at the Finlay Institute; as well as a quadrivalent formula for dengue being investigated at the Genetic Engineering and Biotechnology Center.
Given the innovative nature of these advances, the developers of the three vaccines were awarded National Academy of Science prizes in 2015.
Also in the final stages of clinical trials is a cholera vaccine, on which the Finaly Institute, the Scientific Research National Center, and BioCubaFarma are working jointly.
BioCubaFarma currently produces 10 of the 13 vaccines used in Cuba's national vaccination program, an effort which has eliminated nine diseases and has kept five others under control with very low rates of infection.
One of the most significant impacts of the country's vaccination program has been the control of hepatitis B. No severe cases in children under five years of age have appeared in the country since 1999, and none in those under 15 since 2006. An appreciable reduction in liver cancer is also attributed to control of the hepatitis B virus.
It is one of life’s great enigmas: why do we sleep? Now we have the best evidence yet of what sleep is for – allowing housekeeping processes to take place that stop our brains becoming overloaded with new memories.
All animals studied so far have been found to sleep, but the reason for their slumber has eluded us. When lab rats are deprived of sleep, they die within a month, and when people go for a few days without sleeping, they start to hallucinate and may have epileptic seizures.
One idea is that sleep helps us consolidate new memories, as people do better in tests if they get a chance to sleep after learning. We know that, while awake, fresh memories are recorded by reinforcing connections between brain cells, but the memory processes that take place while we sleep have remained unclear.
Support is growing for a theory that sleep evolved so that connections in the brain can be pruned down during slumber, making room for fresh memories to form the next day. “Sleep is the price we pay for learning,” says Giulio Tononi of the University of Wisconsin-Madison, who developed the idea.
Now we have the most direct evidence yet that he’s right. Tononi’s team measured the size of these connections or synapses in brain slices taken from mice. The synapses in samples taken at the end of a period of sleep were 18 per cent smaller than those in samples taken from before sleep, showing that the synapses between neurons are weakened during slumber.
A good night’s sleep
Tononi announced these findings at the Federation of European Neuroscience Societies meeting in Copenhagen, Denmark, last week. “The data was very solid and well documented,” says Maiken Nedergaard of the University of Rochester, who attended the conference.
If the housekeeping theory is right, it would explain why, when we miss a night’s sleep, the next day we find it harder to concentrate and learn new information – we may have less capacity to encode new experiences. The finding suggests that, as well as it being important to get a good night’s sleep after learning something, we should also try to sleep well the night before.
It could also explain why, if our sleep is interrupted, we feel less refreshed the next day. There is some indirect evidence that deep, slow-wave sleep is best for pruning back synapses, and it takes time for our brains to reach this level of unconsciousness.
The latest brain-slice findings that synapses get smaller is the most direct evidence yet that the housekeeping theory is right, says Vyazovskiy. “Structural evidence is very important,” he says. “That’s much less affected by other confounding factors.”
Protecting what matters
Getting this data was a Herculean task, says Tononi. They collected tiny chunks of brain tissue, sliced it into ultrathin sections and used these to create 3D models of the brain tissue to identify the synapses. As there were nearly 7000 synapses, it took seven researchers four years.
The team did not know which mouse was which until last month, says Tononi, when they broke the identification code, and found their theory stood up.
“People had been working for years to count these things. You start having stress about whether it’s really possible for all these synapses to start getting fatter and then thin again,” says Tononi.
The team also discovered that some synapses seem to be protected – the biggest fifth stayed the same size. It’s as if the brain is preserving its most important memories, says Tononi. “You keep what matters.”