Bumblebees are the big lifters of the insect world, able to fly back to the hive with almost their own bodyweight in nectar on board. A study published Feb. 5 in Science Advances shows how they do it — and that bees can show more flexibility in behavior than you might expect from a bumbling insect.

Even when they’re not high on marijuana, recreational users of the drug display signs of impaired driving, a new study finds.

The findings may come as a surprise to many, said senior study author Staci Gruber, director of Marijuana Investigations for Neuroscientific Discovery (MIND) at McLean Hospital, a Harvard Medical School affiliate in Belmont, Massachusetts.

Hitting more pedestrians

“People who use cannabis don’t necessarily assume that they may drive differently, even when they’re not high,” Gruber said in a hospital news release. “We’re not suggesting that everyone who uses cannabis will demonstrate impaired driving, but it’s interesting that in a sample of non-intoxicated participants, there are still differences in those who use cannabis relative to those who don’t.”

Gruber and her colleagues looked at marijuana users and non-users whose driving performance was assessed on a driving simulator. At the time they used the simulator, the users had not used marijuana for at least 12 hours and were not intoxicated.

Compared to nonusers, heavy marijuana users had worse driving performance during the test. For example, they hit more simulated pedestrians, went over the speed limit more often, made fewer stops at red lights, and crossed the centre line more often.

The researchers also found that the start of marijuana use before age 16 was associated with worse performance on the driving simulator.

The study was published in the journal Drug and Alcohol Dependence.

“What was interesting was when we examined impulsivity in our analyses, most of the differences we saw between cannabis users and healthy controls went away, suggesting that impulsivity may play a role in performance differences,” said study co-author Mary Kathryn Dahlgren, a McLean research fellow.

Acutely intoxicated

In states where marijuana is legal, there’s growing public concern that more people will drive while high. But this study shows that driving can be impaired even in marijuana users who aren’t high and that the public needs to reconsider its understanding of impairment.

“It’s important to be mindful that whether someone is acutely intoxicated, or a heavy recreational cannabis user who’s not intoxicated, there may be an impact on driving, but certainly not everyone demonstrates impairment simply as a function of exposure to cannabis,” Gruber said.

“This is especially important to keep in mind given increasing numbers of medical cannabis patients, who differ from recreational users with regard to product choice and goal of use,” she added.

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Scientists said 99% of understanding of cancer was missing until today.

Rachel Maclean says she now has “doubts about the procedure and my health years later”.

The night she turned 37, Barbara Jackson put her two-year-old daughter Olivia Copeland to bed and walked to the kitchen. She felt a little odd but didn’t think much of it.

The next thing Barbara remembers, she was in the hospital. Doctors were telling her she was a rare survivor of cardiac arrest. Doctors also said they didn’t know why it happened, leaving Barbara concerned it would happen again.

In and out of coma

As she tried grasping it all, her then-husband filled in the gaps: He called 911, and the operator told him to perform CPR. He gave chest compressions for 12 minutes, until the paramedics arrived. Her face had turned blue. They considered declaring her dead but decided to keep trying because of Olivia; she had climbed out of bed and was watching.

Over her three weeks in the hospital, Barbara drifted in and out of a coma. She needed therapy to relearn how to use a knife and fork. Doctors also implanted a defibrillator to regulate her heartbeat.

Today, only about one in 10 people in the United States who suffer a cardiac arrest outside the hospital survive. When Barbara’s heart stopped in 1997, the survival rate was closer to 5%.

Barbara lived in Florida but saw a specialist at Johns Hopkins Hospital when visiting her mom in Maryland six months later. That specialist diagnosed her with long QT syndrome, a disorder of the heart’s electrical activity that is better understood now than in 1997. LQTS can cause irregular and dangerous heart rhythms, known as arrhythmias. These arrhythmias can be fatal if not treated.

Some people get LQTS from medical conditions or medications. However, it’s often inherited, which meant Olivia might be at risk. That uncertainty – and a lack of information about LQTS in children – was stressful enough that Barbara and Olivia eventually moved to Maryland to be closer to Johns Hopkins.

A box in her chest

“Diagnosis is important because with this type of LQTS (type 3), people tend to die in their sleep,” Barbara said. She worried about this every night when putting Olivia to bed.

By the time Olivia was 11, genetic testing was advanced enough to confirm she indeed had LQTS. While someone with LQTS may never have an arrhythmia episode, Barbara didn’t want to take any chances. She scheduled Olivia for surgery to implant a defibrillator.

Olivia remembers the surgery being scary. Her classmates teased her for having a box in her chest. Kids wouldn’t invite her to sleepovers, as their parents feared a heart problem on their watch.

“It was a very lonely time for us,” Barbara said.

A year later, Barbara and Olivia got the support they needed through the American Heart Association.

At 13, Olivia became the Heart Hero for the 25th annual Baltimore Heart Ball and relished the opportunity to talk to other children with heart issues.

Good to know CPR

Olivia, now 24 and living in Florida, can’t skydive or scuba dive because of her defibrillator – “I wouldn’t do that anyway,” she said. But she does compete in mud runs, which involves racing and conquering large obstacles such as scaling rope nets, traversing monkey bars and climbing over walls. Those with genetic forms of LQTS are encouraged to live an active life and exercise, but not to exercise alone, Barbara said.

In addition to telling others to reach out for support if diagnosed with a heart issue, Barbara encourages people to advocate for their own heart health and to know CPR.

She tells people to pay attention to any signs of heart issues, such as chest pain, fainting for no reason or a racing heart. “You can’t test long QT on a deceased person.”

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People with an eating disorder are much more likely to have exercise addiction than those with normal eating habits, British researchers say.

They analysed data from more than 2 100 people who took part in nine studies in the United States, United Kingdom, Australia and Italy.

Stay away from crash diets

People with an eating disorder were 3.7 times more likely to have an exercise addiction than those with no eating disorder, according to the findings.

“It is known that those with eating disorders are more likely to display addictive personality and obsessive-compulsive behaviours,” said study leader Mike Trott, a researcher in sport science at Anglia Ruskin University in Cambridge, England. “We are also aware that having an unhealthy relationship with food often means an increased amount of exercising, but this is the first time that a risk factor has been calculated.”

He noted that it’s common at the start of a new year to want to eat better and exercise. But it’s important to stay away from crash diets or any eating plan that eliminates some foods entirely, he added.

“Our study shows that displaying signs of an eating disorder significantly increases the chance of an unhealthy relationship with exercise, and this can have negative consequences, including mental health issues and injury,” Trott said in a university news release.

Serious medical conditions

He said health professionals working with people who have eating disorders should consider monitoring their exercise.

This group has been found “to suffer from serious medical conditions as a result of excessive exercise, such as fractures, increased rates of cardiovascular disease in younger patients, and increased overall mortality,” Trott said.

The study was published online recently in the journal Eating and Weight Disorders – Studies on Anorexia, Bulimia and Obesity.

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UCLA bioengineers and colleagues at UNC School of Medicine and MIT have further developed a smart insulin-delivery patch that could one day monitor and manage glucose levels in people with diabetes and deliver the necessary insulin dosage. The adhesive patch, about the size of a quarter, is simple to manufacture and intended for once-a-day use.

Microbes are known to affect digestion, mood and overall health, and now Princeton researchers have shown that a shift in the microbiome is linked to cancer — at least in a threatened subspecies of foxes found only on one island off the California coast.

Their research suggests a several-step process: First, the cat-sized Santa Catalina foxes become infested with ear mites, which change the foxes’ microbiome and allow a staph infection to take hold. As Staphylococcus pseudintermedius runs rampant, the antibiotic-resistant infection leads to chronic inflammation of the foxes’ ears. In that environment of inflamed tissue, tumors can flourish. The researchers detailed their findings in the journal Molecular Ecology.

“We were really excited to find such clear results,” said Alexandra DeCandia, the first author on the paper and a graduate student in the lab of Bridgett vonHoldt, an associate professor of ecology and evolutionary biology at Princeton University. “Everything we found — reduced species diversity, shifts in community composition, overabundance of potentially pathogenic species — fit within our expectations.”

The project started during conservation efforts on Santa Catalina Island, when researchers noticed that roughly half of the adult foxes had tumors growing in their ears. That’s one of the highest tumor rates ever observed in wildlife, prompting immediate follow-up study.

Early work demonstrated a link between ear mite infection and tumor growth. Most researchers theorized that ear mites led to chronic inflammation, ultimately sparking the growth of tumors. DeCandia and vonHoldt’s team wanted to know whether the microbiome also played a role in this system.

That focus on diversity within the microbiome makes their work “an excellent example of where the field is going to move in the future,” said George Amato, the director of conservation genomics at the American Museum of Natural History, who was not involved in this research. “We’ve only recently learned how important the microbiome is to an individual’s health — whether it’s an animal or a human,” he said. “Previously, scientists only examined part of the picture. They certainly weren’t looking at microbiomes — they didn’t even have tools to do it. … By examining that, we’ve come to understand that a lack of diversity in that microbial community, combined with the genetics of the foxes, best helps us understand not only the threat of this particular disease but other diseases as well. This really is a new paradigm for understanding threats to endangered species.”

The threatened Santa Catalina foxes are one of six subspecies of Channel Island foxes (Urocyon littoralis) that live on six of the eight Channel Islands off the coast of southern California. Several of the subspecies, including those on Santa Catalina (U. littoralis catalinae), have made impressive rebounds from the brink of extinction — with the result that they are all incredibly similar genetically, nearly clones of each other.

The foxes’ almost total lack of genetic diversity makes them fascinating research subjects, said DeCandia.

“We typically view genetic diversity as a good and necessary thing,” she said. “It keeps organisms healthy — think of the negative health effects associated with inbreeding — and helps populations survive unexpected changes to their environment. But despite having almost no genetic variation, these foxes exhibit very few signs of poor health or inbreeding depression. That leads us to wonder whether other forms of diversity — such as their resident organisms — become important players in health and immunity. That’s why we focused our study on the microbiome and disease in these foxes.”

The link between microbes and cancers was an unexpected find, DeCandia said. “When we first set out to do this study, we simply wanted to characterize the microbiome across a few different body sites in the foxes. Just as 19th-century naturalists would charge into a new habitat and catalogue species, we originally intended to catalogue microbes. However, after looking at ear canals more closely, we found there was a lot of variation associated with mite infection status. We then pivoted the paper to focus almost entirely on ear canal microbes associated with mite infection!”

With their collaborators from the Catalina Island Conservancy, they swabbed dozens of foxes to collect microbes, then extracted DNA to determine which microbes were present in all of their samples — and in what relative abundances.

“Since microbes exist within a community, relative proportion matters,” DeCandia said.

They found that mite-infected ear canals had significantly different microbial communities than uninfected ears. Overall species richness was lower, and relative abundance was skewed toward one bacterial species: S. pseudintermedius, which is common on canids (including dogs) and can become an opportunistic pathogen when communities are disrupted — such as by an infestation of mites.

The staph microbe then forms antibiotic-resistant biofilms that are “incredibly difficult” for the immune system to eradicate, said DeCandia. As a result, this strain of staph is linked to chronic inflammation in many species.

The researchers are still trying to clarify the cause and effect relationships — for example, whether the mites bring in the staph microbes or they were present but latent until the mites caused enough structural damage to allow the staph to have a population boom — but the string of correlations is clear: mite infection is linked to a proliferation of S. pseudintermedius, which is linked to the chronic inflammation associated with tumorigenesis.

One major outstanding question is why, of the six Channel Island fox subspecies, only three have mites and only one — the Catalina Island foxes — show significant tumor growth.

The new study reinforces previous research in which members of vonHoldt’s lab, including Kennedy Leverett of the Class of 2020, studied changes in the skin microbiome associated with sarcoptic mange, which is caused by a different species of mite. They looked at coyotes, red foxes and gray foxes and found remarkably consistent signatures of microbial disruption that almost exactly matched the island fox study: Infected individuals had reduced microbiome diversity and higher abundance of S. pseudintermedius.

“Considered together, these two studies suggest that this microbial species is an important player in canid microbiomes and may function in a number of diseases,” DeCandia said.

A new handheld 3D printer can deposit sheets of skin to cover large burn wounds — and its “bio ink” can accelerate the healing process.

It comes as a woman on a flight which helped repatriate UK citizens tested positive for the virus.