Category: Health & Medicine

STDs Might Have Driven Us to Embrace Monogamy

By Rob Knell, Queen Mary University of London | April 13, 2016 2:17 pm
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(Credit: Ivan Galashchuk/Shutterstock)

Exactly why so many humans choose monogamous pair bonds over juggling multiple partners has long been a mystery to scientists. After all, having several partners at the same time should lead to more offspring — an outcome you’d think evolution would favor. Now a new study has linked the phenomenon to sexually transmitted diseases, arguing that monogamy could have evolved because it offered protection against the threat of infection.

Monogamy is, of course, the norm in Western societies. But there are many cultures where a husband can have more than one wife (polygyny) or, less commonly, a wife can have more than one husband (polyandry). This diversity of human mating systems is also hard to explain. What we do know, however, is that many hunter-gatherer societies, living in small groups, were most often polygynous (and many remaining groups still are). But with the rise of agriculture, societies tended to become more complex — and less polygynous. In the most strictly monogamous societies, there was often a social punishment for polygynists, either informally or, as in many modern societies, through a legal system. Read More

As Seen on Television: The Dawn of Modern Medicine

By David Warmflash | March 30, 2016 6:00 am
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To keep The Knick historically accurate, on-set surgical advisor Dr. Stanley Burns (pictured below) relied on his expertise and his massive collection of historic medical photos stored at The Burns Archive in New York. (Credit: Paul Schiraldi/HBO)

They scrub in according to a strict protocol. All instruments are sterile, the patient is put to sleep, and an incision is cut and held open with retractors. Moving into the abdominal cavity, surgeons clamp bleeding arteries and cauterize tissues meticulously to prevent blood loss while also making the surgical field easier to see.

Thus far, it seems just like surgery today, but for the numerous people overlooking from elevated theater seats, dressed in formal Victorian outfits. That’s the operating room setting on the Cinemax period medical drama, The Knick. There are a host of other details that make the setting look ancient, but the differences from modern surgery are most striking when things start going wrong.

For instance, the patient’s heart rate becomes rapid, then erratic, and the surgeon knows this only because of a nurse listening to the patient with a stethoscope. She can’t report blood pressure, because no device is set up to measure it — there are no monitors of any sort. Those devices don’t exist in the era when The Knick is set, nor would they help much, since the time period denies doctors even the most basic tools of resuscitation. The year is 1900, when many basic principles of surgery have been developed, but safe transfusions, electrocardiography, and other vital tools still lay several years into the future. Read More

What Lessons Will We Learn From Zika?

By Carl Engelking | February 5, 2016 6:09 pm
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A female Aedes aegypti mosquito. (Credit: U.S. Department of Agriculture/Flickr)

Zika virus caught the world off guard, but it shouldn’t have.

The rapid spread of the mosquito-borne virus, and its possible connection to birth defects and neurological disorders, compelled the World Health Organization on Monday to declare an international public health emergency. But by that time 1.5 million Brazilians had already caught the virus, and it had spread to 24 countries in the Western Hemisphere. The current tally from the Centers for Disease Control and Prevention indicates 30 countries are now reporting active transmission.

“It seems like we are always behind,” says Jorge Osorio, a professor of infectious diseases at the University of Wisconsin-Madison. Osorio returned to the United States on Friday after a research stint in Colombia, where the total of confirmed Zika cases is second only to Brazil. “We knew it was a matter of time before this would happen.”

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Countries and territories with active Zika virus transmission. (Credit: CDC/NCEZID/DVBD)

There’s no doubt that a rapid global response — like what’s currently underway — is needed, but Zika’s transformation from a sleeping virus to a global crisis is all too familiar. Since the 1970s, global re-emergence of mosquito-borne infectious diseases has only accelerated. In 2001, global cases of dengue fever skyrocketed. In 2004, chikungunya re-emerged in East Africa and spread worldwide. But with every new outbreak, a recurring flaw in the approach toward infectious disease control is exposed: We’re consistently reactive.

“It’s sort of human nature. We react to the thing that’s on fire, but we aren’t so good at prevention,” says David Katz, a certified board specialist in public health and founding director of Yale University’s Yale-Griffin Prevention Research Center. “We neglect the factors that produce emerging infectious disease, and in the blink of an eye we have a global crisis on our hands.”

A Period of Apathy

By the late 1960s humanity was winning its war with malaria, yellow fever, dengue and a host of other diseases. Proactive, aggressive eradication efforts eliminated the Aedes aegypti mosquito — the primary carrier of infectious diseases — in 23 countries. But our declaration of victory was specious.

Duane Gubler, a professor of emerging infectious diseases at Duke-NUS Medical School in Singapore, noted in a 2011 review that our comfort in victory kicked off a period of “increasing apathy and complacency” toward controlling infectious diseases. A new, more reactive paradigm of surveillance and emergency response was adopted for disease control, and resources shifted to other diseases.

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A look at how Aedes aegypti populations rebounded in tropical Americas from 1930 to 2011. (Credit: Duane Gubler, “Dengue, Urbanization and Globalization: The Unholy Trinity of the 21st Century,” Tropical Medicine and Health, Vol. 39, No. 4 Supplement, 2011, pp. 3-11)

In the four decades that followed, unprecedented population growth occurred around the world, and more people converged in crowded urban centers. Mosquitoes that once spread diseases in remote, less-populated locales had millions more human hosts to bite and infect in confined areas. On top of that, advances in global transportation made the world smaller and further enhanced the ability of viruses to expand their reach. Today, a respond-to-an-emergency approach can’t keep up with the ability of viruses to mutate and spread.

“We live in a crisis-oriented society. But this has been going on for the better part of 40 years as we’ve seen these global pandemics of infectious diseases spread,” says Gubler. “We wait for them to occur.”

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The emergence of the dengue in the Americas was associated with the introduction of new variations of the virus. (Credit: DengueNet 2007 data provisional via Duane Gubler, “Dengue, Urbanization and Globalization: The Unholy Trinity of the 21st Century,” Tropical Medicine and Health, Vol. 39, No. 4 Supplement, 2011, pp. 3-11)

Writing Was on the Wall

Infectious disease researchers could see Zika’s warning signs long before the outbreak captured headlines. The virus was isolated in 1947 from rhesus monkeys in Uganda. Only sporadic human Zika infections were reported since its initial discovery, and its clinical presentation didn’t sound alarms. Oftentimes, infected people wouldn’t know Zika was in their system. For that reason, the virus didn’t garner much attention or warrant funding for research.

“In the United States, research for all science and infectious diseases has been at historic lows, so to get funding for Zika virus, which wasn’t causing many infections, was nearly impossible,” says Matthew Aliota, a research scientist at the UW-Madison School of Veterinary Medicine.

It wasn’t until 2007 that a Zika epidemic swept through Yap Island in the Federated States of Micronesia. A larger epidemic followed in French Polynesia in 2013-14. In May 2015, the Pan American Health Organization issued an alert about the transmission of Zika virus in Brazil. And in July, Gubler sounded the warning in an issue of The Lancet.

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A transmission electron micrograph of Zika virus. (Credit: Cynthia Goldsmith/CDC)

“We essentially predicted this months ago, and said it would follow in the footsteps of chikungunya because it has the same epidemiology,” says Gubler. “Part of our problem is that we have a mentality of looking at these viruses, including a lot of virologists, as monolithic species. These viruses change genetically, and those changes affect expression.”

Today, a virus that was largely ignored is now affecting human health in ways we didn’t anticipate. In other words, a virus that’s lying dormant doesn’t make it less of a threat to world populations. And with half the world’s population living in areas susceptible to infectious diseases, a virus that’s gone quiet doesn’t mean it won’t come roaring back.

“Yellow fever is another virus that’s sitting in the wings. It still exists in West Africa, but it’s been relegated for the past 60 years,” says Gubler. “If, or when, it starts causing trouble, it will make all of these other outbreaks pale by comparison.”

Preventing the Next Outbreak

That’s why Gubler, Osorio, Katz and others advocate for going on the offensive to strike viruses before they spiral out of control — even benign viruses. With adequate resources, vaccine development could be accelerated. Mosquito populations could be kept in check. Researchers across scientific disciplines could collaborate to build ways to predict future hotspots for outbreaks and focus energies there.

“You need to rebuild public health infrastructure in endemic countries and develop the lab capacity to support a surveillance system to give you some predictive capability,” says Gubler.That requires investment, dedication and some bit of faith on the part of policymakers that this is money well spent.”

Osorio and Aliota are working in Colombia to build more accurate laboratory diagnoses of Zika, dengue and chikungunya. The other focus of their research is to track the way Zika and viruses like it evolve and adapt in their hosts. Their research has shown that Zika split into two distinct lineages, African and Asian. The strain they’re seeing in Colombia can be traced back to the strain that existed in the 2013-14 outbreak in French Polynesia. But their work has a larger aim: predicting how viruses will mutate to get ahead of the next outbreak.

“I’m trying to be more predictive using lab studies and experimental evolution in the lab to be more proactive,” says Aliota. “It’s idealistic thinking, but we’re working to predict the evolvability and adaptability of certain viruses.”

Building a more thorough global network of early detection centers around the world is also essential for pivoting to a proactive approach to infectious disease. Expanding the reach of organizations like the Global Virus Network, which is composed of research centers around the world that focus on viral causes of human disease to prepare for novel pandemic threats, could provide enough warning stay ahead. A robust, global virus detection system could operate similarly to the global array of earthquake-detecting instruments that give advance notice of a potential disaster.

“We must continue to create those centers around the world, and ensure they are funded and equipped with people who are well trained to do this,” says Osorio. “Early indication is important, and it gives us the ability to take measures right away.”

Interdisciplinary Approach

“We need to look at culture, epidemiology, economics and ecology at a local level and develop strategies from there,” says Gubler, who helped form the Partnership for Dengue Control, which brings health experts together to do that.

Overall, infectious disease researchers are pushing toward a more interdisciplinary approach to predict outbreaks. Jonathan Patz, director of the Global Health Institute at UW-Madison, is doing research to connect the dots between climate change and global health, offering a glimpse into the ways differing scientific fields can combine to build a proactive approach to mosquito-borne disease. His research has revealed a link between dramatic climactic shifts and the occurrence of viral outbreaks.

“Extreme drought conditions tend to drive the proliferation of Aedes aegypti. Epidemics of Zika, dengue and chikungunya have been preceded by drought,” says Patz. “This year, the el Nino event is looking like the strongest on record. During el Nino, northeastern brazil is generally affected with drought.”

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NOAA declared 2015 as the world’s hottest year on record. In the same year northern Brazil, Colombia, parts of Venezuela, Peru and Ecuador experienced record heat.

Patz notes there are myriad other variables that shift weather patterns and the spread of disease. But, generally speaking, he is finding that drought is a contributing factor. Patz’s work reflects a larger shift toward looking beyond the infectious agent and building a broader recognition of factors that are in play. 

“It’s getting much better in terms of interdisciplinary focus,” says Aliota. “I never thought, when I first got into the hard sciences, that I would be talking to geographers, anthropologists and the other disciplines in my work.”

Of course, controlling the populations of A. aegypti, the source of the problem, is also a key area of research. Methods of population control, and wider access to mosquito nets and repellant in poor countries are essential. There’s also emerging interest in research to genetically modify mosquitoes. The research could limit their ability to breed — or wipe them out completely.

“Mosquito control has been left wanting for over 40 years, and that’s catching up with us,” says Gubler.

In It Together

If there’s any silver lining from the surge in outbreaks, it’s that it brings into sharp focus the sheer connectedness of humanity. Zika, dengue and chikungunya don’t respect political borders. Outbreaks are forcing us to break long-standing lines of division and embrace the fact that we are one species.

“Zika does not give a damn about whether you are Muslim, Jewish or Christian,” says Katz. “The world is small, and there is no ‘over there anymore.’ We’re all in the same petri dish. I think that shift in thinking is fundamental to our preparedness.”

CATEGORIZED UNDER: Health & Medicine, Top Posts

Nerve Stimulation Offers Hope for PTSD Sufferers

By Ben Thomas | February 3, 2016 11:02 am
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Ron Ramirez, a retired Army sergeant is participating in the second phase study investigating the effectiveness of external trigeminal nerve stimulation for veterans with PTSD. Andrew Leuchter is conducting the research as at UCLA’s Semel Institute for Neuroscience and Human Behavior. (Credit: Reed Hutchinson/CalFoto/UCLA)

Millions of people are suffering from post-traumatic stress disorder (PTSD) right now. Among military personnel who’ve been deployed to Iraq and Afghanistan, an estimated 31 percent are PTSD sufferers. An estimated 52 percent of people with PTSD also suffer from major depressive disorder (MDD).

The cost of treating these disorders is estimated to run as high as $40 billion per year. The social consequences are harder to quantify, but many PTSD and MDD sufferers report marital problems, difficulties bonding with family and friends, and chronic suicidal thoughts.

But a team of researchers led by Andrew Leuchter, professor of psychiatry and biobehavioral sciences at UCLA, believes it has found a new treatment for PTSD and MDD. It’s not a new drug or a new form of psychotherapy. It’s a form of electronic nerve stimulation. Read More

MORE ABOUT: mental health

The Trouble With Head Transplants

By Andrew Jackson, Newcastle University | February 2, 2016 1:06 pm
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(Credit: Taveesak Pansang/Shutterstock)

In a 1978 essay, titled Where Am I?, the philosopher Daniel Dennett suggested that the brain was the only organ of which it’s better to be a transplant donor than recipient. Now Italian neurosurgeon Sergio Canavero wants to turn philosophical thought experiments into reality by transplanting the head of Valery Spiridonov, who suffers from a debilitating muscle wasting disease, onto the healthy body of a dead donor.

Beside posing questions about personal identity, there are more prosaic challenges that must first be overcome. The brain would have to be kept alive during surgery by cooling it to 10-15°C, and the immune system would need to be powerfully suppressed to prevent transplant rejection. But the greatest hurdle may be how to restore connections to the spinal cord. Without this connection the brain would have no control of its new body. Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: medical technology

Fountain of Youth: The Secret Power of Friends and Family

By Jo Marchant | January 21, 2016 10:39 am
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(Credit: Jacob Lund/Shutterstock)

The Nicoya peninsula in northwestern Costa Rica is one of the most beautiful places on the planet. This 75-mile sliver of land, just south of the Nicaraguan border, is covered with cattle pastures and tropical rain forests that stretch down to the crashing waves of the Pacific Ocean. The coastline is dotted with enclaves of expats who fill their time surfing, learning yoga and meditating on the beach.

For the locals, life is not so idyllic. They live in small, rural villages with limited access to basics such as electricity, linked by rough tracks that are dusty in the dry season and often impassable when it rains. The men earn a living by fishing and farming, or work as laborers or sabaneros (cowboys on huge cattle ranches), while the women cook on wood-burning stoves. Yet Nicoyans have a surprising claim to fame that is attracting the attention of scientists from around the world.

Their secret was uncovered in 2005 by Luis Rosero-Bixby, a demographer at the University of Costa Rica in San José. He used electoral records to work out how long Costa Ricans were living, and found that their life expectancy is surprisingly high. In general, people live longest in the world’s richest countries, where they have the most comfortable lives, the best health care and the lowest risk of infection. But that wasn’t the case here. Read More

Taming the New Frontiers in Gene Editing

By Sarah Scoles | November 17, 2015 1:10 pm

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The world’s most powerful gene-editing tool, CRISPR-Cas9, gives humans the ability to swap out sections of the genome with less money and time than ever before. That’s a lot of power, and with great power comes great responsibility.

But right now, most of the world doesn’t have regulations about what scientists — and someday, hobbyists — can and can’t do to the double helix. In China, scientists have used CRISPR-Cas9 to modify human embryos. And that has left the rest of the world a little nervous. Read More

Getting ‘High’ On Your Own Supply

By Ben Thomas | October 19, 2015 3:58 pm

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Earlier this month, researchers discovered that at least part of the euphoria that comes after a strenuous workout — runner’s high — is due to endocannabinoids, the body’s self-produced counterparts to some of marijuana’s mood-enhancing chemicals.

The finding overturned decades of conventional wisdom claiming that natural highs come from endorphins, the chemicals that became famous in the 1980s for their euphoric effects. While endorphins seem to help numb our muscles during a workout, their molecules are too large to cross the blood-brain barrier and trigger a “high” like endocannabinoids can. Read More

Dad’s Experiences Affected You, Even Before You Were Born

By Paul Haggarty, University of Aberdeen | October 13, 2015 11:37 am
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The lifestyle and environment of men can have implications on their children before they decide to become fathers. (Credit: Volt Collection/Shutterstock)

It might not just be expectant mothers who have to pay attention to their lifestyle. Now a new study published in Science could be relevant to a growing body of research looking at ways in which the lifestyle and environment of men before they become fathers could influence the lives of their children and grandchildren.

We know that many human traits, such as weight, height, susceptibility to disease, longevity or intelligence, can be partly inherited, but researchers have so far struggled to identify the precise genetic basis for this. This may partly be due to limitations in our understanding of how genetics works, but now there is growing interest in the potential for something called “epigenetics” to explain this heritability. Read More

I Sent a Sample of My Poop to uBiome

By Sarah Scoles | October 7, 2015 11:59 am
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(Credit: VGstockstudio/Shutterstock)

My sample kit from uBiome stared at me from the kitchen table. Inside its sleek black cover, latched with Velcro, a single high-tech Q-tip awaited. On some morning of my choosing, I was to dab that Q-tip on a piece of used toilet paper, seal it up, and send tiny particles of my excrement back to the uBiome headquarters in downtown San Francisco. There, researchers would parse it and let me know what organisms squirmed around my intestines.

uBiome, a biotech startup, exists to help people explore their microbiomes — the population of tiny organisms that live inside you, outnumbering your own cells 10(ish) to 1(ish). I wanted to know how my own microbiome compared to other people like me: youngish people who run a lot who are generally healthy but sometimes eat large cheeseburgers.

But like other genetic test providers, including 23andMe and Ancestry.com, the company has a second and less visible objective. Users participate out of curiosity, health concerns — or, in the case of the still-nascent science of the microbiome, sheer novelty. But their data is the ultimate prize, which those companies, with participant permission, can study, share, and sell.

Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts
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