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Edward Wozniak was sitting on his porch in Uvalde, Texas, one day in 2010 when a dog lying nearby stood up and a nickel-sized insect fell from its belly. Wozniak recognized the insect as a triatomine bug—the vector that carries the parasite Trypanosoma cruzi— and rushed to capture it. When the insect tested positive for the parasite, Wozniak launched a public effort to collect the bugs in Texas. “I had no problem getting almost 400 of them from in and around houses over a three-year period,” Wozniak said, “which blew me away.”The T. cruzi parasite causes Chagas disease, which is designated a “Neglected Tropical Disease” by the World Health Organization. Chagas is most prevalent in Central and South America, where experts estimate it afflicts some 6 to 8 million people, and has only recently gotten attention in the United States. Now, <a href="http://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0005074#pntd.0005074.ref005">a new study</a> has found the parasite that causes Chagas in overlapping populations of humans, dogs, coyotes, and insects in southern Texas, adding a new dimension to the evidence that the potentially fatal disease can be acquired locally in the U.S.
 

 
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 T. cruzi lives in the feces of triatomine bugs. Nicknamed “kissing bugs,” these nocturnal insects bite people (often near the mouth) while they’re sleeping and feed on their blood. The bugs defecate while feeding, and if the feces are rubbed into the person’s bite wound, mouth, or eyes, they can contract the disease.Because Chagas victims are often symptom-free or experience only generic flu-like symptoms in the first weeks or months of infection, the disease often goes unnoticed. But some 30% of infected people will develop severe cardiac disease up to 30 years later. In Latin America, Chagas is a leading cause of cardiac complications, causing about 12,000 deaths per year. Because kissing bugs thrive in mud walls and poorly constructed shelters, poor communities are often hit the hardest.The researchers deemed the south Texas border area to be at high risk for Chagas partly because of its high poverty rate. The study focused on nine south Texas counties near the Mexican border to get a sense of the parasite’s prevalence across species. They tested samples of human blood as well as blood serum from shelter dogs and coyotes that had been collected during overlapping periods from 2005 to 2009. Additionally, they tested over 100 kissing bugs that had been collected near people’s homes in six of the nine counties from 2012 to 2013. They found T. cruzi in 56% of the kissing bugs, 8% of the coyotes and 3.8% of the dogs. Of the three people who tested positive for Chagas, they believe there is evidence that one of them contracted it locally.Based on these numbers, the researchers estimate that the Chagas disease burden in the Rio Grande Valley could be as much as 23 times higher than they had previously thought, which would mean 4,600 people in the region are currently infected.In Hidalgo County, both coyotes and kissing bugs tested positive for T. cruzi . Steven Hinojosa, lead epidemiologist at the Hidalgo County Health Department, said those study results were something he would “definitely expect to see.” He said he believes the disease is underdiagnosed, but it’s hard to know by how much since they only have three full years of data. Chagas disease only recently became a “notifiable condition,” meaning that doctors are required to report positive cases to government health officials.When a case is reported, treatment must be coordinated between the physician and the Centers for Disease Control and Prevention (CDC). This is because the two drugs used to treat the disease are not FDA regulated, said Melissa Garcia, an instructor at Baylor College of Medicine and an author of the study. Although the drugs are decades old, safe, and widely available in Latin America, they aren’t licensed in the United States because there is no perceived demand for them, she said.Before patients can get medication, they have to get tested for the disease. Everyone contacted for this article said that a primary obstacle to addressing Chagas in the United States is the fact that physicians are either unfamiliar with the disease or refuse to believe that it is present in this country. Although records of T. cruzi -infected kissing bugs in Texas date back to the 1930s and the first confirmed case of locally acquired Chagas was in 1955, many physicians consider the disease to be limited to immigrants who contracted it in Latin America.Wozniak, a zoonosis control veterinarian with the Texas Department of State Health Services, has seen physician pushback time and again. People still send him kissing bugs they find in their homes, which frequently test positive for both T. cruzi and human blood. When positive results are returned, he advises people to get tested themselves. “That’s where we hit a brick wall,” Wozniak said. They will sometimes go from doctor to doctor, only to be turned away, he added.
 

 
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 Candace Stark of LaGrange, Texas, ran up against similar challenges. Stark, 52, donated blood in 2013 and was later notified that her blood had tested positive for T. cruzi . She went to her doctor, and he sent her to an infectious disease expert who said he had never treated a patient with Chagas. The CDC later confirmed her diagnosis, but when she asked her doctor if she should warn her neighbors about the disease, he advised her to keep quiet unless she wanted to be treated like Typhoid Mary. Stark eventually did receive an antiparastic drug to treat Chagas, but once treatment was complete, no follow-up plan was established.“I don’t know if [the drug] worked,” she said.By including both dog and coyote populations in their study, Garcia and her colleagues shed light on different transmission cycles of T. cruzi . “We can learn a lot by looking at wildlife because what they’re carrying can predict risk of human disease,” said Sarah Hamer, an assistant professor at the College of Veterinary Medicine and Biomedical Sciences at Texas A&amp;M University, who was not involved with the study. The parasite is strongly associated with wild animals, but domestic dogs may bridge the gap between wild animals and humans by serving as a host to kissing bugs and a “reservoir” of the parasite near human habitations.Garcia said that in Texas, veterinarians are “absolutely” more on top of Chagas than physicians. “I get many more vets that tell me they’re aware of [Chagas],” she said. She suggests it could be because dogs present with Chagas sooner, developing heart failure within a matter of months rather than decades. They are also at risk of eating the kissing bugs, which could explain why there is a higher rate of Chagas among animals than among people, she said.Despite the obstacles, Garcia feels that health experts and researchers are making progress in tackling Chagas in Texas. In 2015, the CDC awarded a $544,000 grant to a researcher at the University of Texas Health Science Center for Chagas outreach and education efforts.“I think in Texas we’re doing a decent job of getting the policies up to date,” Garcia said. “It’s now a mandatory reportable condition so at least it’s somewhat on people’s radar. However, in other states, like Louisiana, there’s not really any policy.”Meanwhile, Wozniak continues his efforts to educate the public about Chagas disease. “It’s something that’s here, it’s something that needs to be recognized, and people should be tested for it,” he said.
 

 
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Kissing bugs, seen here its with eggs, carry the parasite that causes Chagas disease. Image Credit: Jim Gathany/CDC

Chagas Disease More Prevalent in U.S. Than Thought

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 Astronomers have discovered a giant exoplanet that’s hotter than most known stars. Clocking in a 7,820˚ F, the planet known as KELT-9b orbits a star almost twice as hot as the Sun.The planet, which is almost three times the size of Jupiter, is “tidally locked,” meaning that the same side is always facing its host star. It’s also extremely close to its host, taking only one and a half Earth days to orbit the giant blue star.The team that made the discovery, led by astronomers at The Ohio State University and Vanderbilt University, <a href="http://www.nature.com/articles/nature22392.epdf?referrer_access_token=Y8d_4QkewKNy0J7XHlThSdRgN0jAjWel9jnR3ZoTv0MYcvHnMqfjUp746R6R_ZGjf5O7TtFcqKksjUiYfUP9m2y59Btw4rLkTEulxBKCyCICNDnfpXxyksvIXAK3mQIylPFAdr5N3qYS3BUgzH_mmkJ_OkU99x-MXtjlvVzDq_9vi9U4zBNflgHq-LngWjZ2pwdS7E5sOa_WTfXQHHOAaaNN3Z236b1Lora83iKNg4WCwR9-3oFCDtJ-mP7zFuaZTBUhiCydhv4OSsAkVFzSzMxtGSnNGm55aHg3s5e1_Vo5erBYOjYWmr3J2g5WuoaK&amp;tracking_referrer=www.npr.org">reported</a> its findings in the journal Nature. Scott Gaudi, an astronomer at Ohio State and lead author on the study points out that KELT-9b’s extreme temperature affects it in unusual ways.“It’s a planet by any of the typical definitions based on mass, but its atmosphere is almost certainly unlike any other planet we’ve ever seen just because of the temperature of its day side,” Gaudi said <a href="https://news.osu.edu/news/2017/06/05/hotplanet1/">in a statement</a> .Here’s Ben Guarino, reporting for the <a href="https://www.washingtonpost.com/news/speaking-of-science/wp/2017/06/05/the-hottest-planet-ever-discovered-has-an-atmosphere-as-warm-as-a-stars/?utm_term=.0088be4a90d7">Washington Post</a> :Though scientists had previously discovered “hot Jupiter” planets, so named for their extreme temperatures and gas giant nature, all fell about a thousand degrees Celsius short of KELT-9b. KELT-9b is at the “extreme end of the population” of known gassy, hot giants, said <a href="https://www.astro.ucsc.edu/faculty/profiles/singleton.php?&amp;singleton=true&amp;cruz_id=jfortney">Jonathan Fortney</a> , a University of California at Santa Cruz professor who creates computer models to determine what’s in an exoplanet atmosphere.
 

 
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 Fortney, who was not directly involved with this paper, was asked to model KELT-9b’s atmosphere. He declined. “I can’t possibly do that. The planet’s way, way too hot,” he said.A planet’s atmosphere is typically made up of molecules, which are made up of atoms bound together. Molecular hydrogen gas is common on Jupiter, for instance, as are water vapor and other gases on Earth. KELT-9b’s dayside is an exception. The heat breaks molecules into its constituent atoms. “Almost all the elements are in atoms, not in molecules,” Fortney said. “It’s essentially too hot for molecules to exist.”The team made the discovery using relatively inexpensive off-the-shelf technology in the form of a KELT, or Kilodegree Extremely Little Telescope. Gaudi said their discovery is unusual because astronomers typically focus on smaller, cooler stars whose planets might support life. By contrast, KELT-9b’s host star is so hot that the exoplanet may be trailing a comet-like tail of its own evaporated material.
 

 
 Image credit: Robert Hurt, NASA/JPL-Caltech
 

 
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A Jupiter-like planet and its hot "A-type" host star.

Newly Discovered Planet Is Hotter than Most Stars

A deadly, sluggish marine snail may have revealed the key to fast-acting diabetes therapies.The geography cone snail ( Conus geographus ) is a fish-hunting mollusk that kills its prey by flooding their gills with an ultra-fast-acting insulin that sends the fish into hypoglycemic shock. Researchers have now shown that the geography cone’s weaponized insulin binds with human insulin receptors, and they have uncovered the molecular structure that’s responsible for its lethal speed.
 

 
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 Researchers from Utah and Australia discovered that the snail insulin works more quickly than human insulin because it lacks a “hinge” structure at the molecular level, which they describe in a recent paper published in Nature Structural and Molecular Biology . In human insulin, the hinge slows activity in two ways: one, by causing the molecules to clump together in groups—which must break apart before the individual insulin molecules can bind with receptors—and two, by preventing binding until the hinge is open. Scientists looking to develop faster insulin have seen the hinge as an obstacle, but simply removing it hasn’t been an option.“If you chop that off, the human insulin is dead, it doesn’t work,” said Mike Lawrence, an associate professor at Melbourne’s Walter and Eliza Hall Institute of Medical Research and corresponding author of the study. Since past attempts to remove the hinge have rendered insulin useless, scientists were struck by the fact that the snail insulin lacks the human version’s hinge piece entirely, but still activates human insulin receptors.“The question is, how does it get around not having that piece?” Lawrence said. “And the answer is that by putting one residue—one amino acid at another point in the protein—that serves the purpose of the hinge.Lawrence said that while researchers have experimented with removing the hinge in the past, it’s unlikely that anyone might have tried removing it while also adding the additional amino acid at the location where it occurs in the snail insulin.“There would have been no logic to doing that,” Lawrence said. “But through evolution, the cone snail has developed this methodology of creating a very fast-acting insulin.”This research builds on a 2015 paper that detailed the insulin-based nature of the geography cone’s venom. It is the first known use of insulin in venom, and scientists found that the weaponized insulin paralyzes the prey because it is structured like fish insulin rather than the snail’s own insulin. Since fish insulin is similar to human insulin, researchers saw the possibility that the snail’s weaponized version would bind with human insulin receptors.It is not unusual for researchers to look to animal venoms as a source of potential medical therapies because, like many drugs, venoms tend to be both potent and highly targeted to specific molecules. There are at least six FDA-approved drugs derived from animal venoms, including a diabetes drug derived from Gila monster saliva and a pain medication derived from another species of cone snail. Other medications come from various snakes and a leech.For Helena Safavi-Hemami, an author on the paper, the decision to study cone snail venoms had to do with their unusual richness. She said that in cone snail venom “there is a great diversity of venom peptides that’s really not seen in other venomous animals,” and that many of these peptides are highly targeted to specific receptors. Those factors make the venom more likely to contain something medically useful.
 

 
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 The team’s paper concludes that their discovery could aid in developing fast-acting insulin therapies for humans, and Lawrence said a next phase of research has already begun.“There is a very, very long way from this finding to a clinically useful, novel insulin,” said Peter Kurtzhals, senior vice president and head of global research at Novo Nordisk, a pharmaceutical company specializing in diabetes treatments. He said that the next step would be to study the many aspects of how the insulin would work in the human body. Even so, he recognized the significance of understanding the structure of the cone snail’s hinge-free insulin.“It’s an inspiration to what you could engineer,” he said.
 

 
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The geography cone snail uses one of the world's most dangerous venoms to immobilize its prey. Image Credit: Photo credit: Baldomero Olivera, Ph.D., University of Utah

Deadly Sea Snail Venom Could Hold Key to Faster Insulin Therapies

Some energy and climate projections may have been distorted by inflated estimates of available coal, a new study shows.Since the 1990s, climate and energy models have assumed we’d use the entirety of the world’s coal reserves, but it has become clear in recent decades that only about a third of all coal deposits can feasibly be recovered.But, researchers warn, changing those assumptions doesn’t alter the forcasts of the lowest-emission—but still risky—climate scenario.The mismatch in coal usage estimates and actual availability results surprised researchers Justin Ritchie and Hadi Dowlatabadi, of the University of British Columbia, who published their findings last month. Coal had once been assumed to be essentially unlimited (for the purposes of modeling), and their new estimates severely constrained the potential supply—so much so that the worst case climate scenario put forth by the Intergovernmental Panel on Climate Change, which assumes an increase in future coal use, may not be possible. At least not in the way scientists thought.When Ritchie and Dowlatabadi adjusted their model to account for the lower coal estimates, they substituted natural gas or renewable energy for additional coal use in coal’s place. When natural gas picked up the slack, emissions fell by 15%, and when renewable energy filled the gap, emissions estimates fell by 30%.Eric Roston, reporting for Bloomberg:The discovery that there’s a whole lot less coal to burn would seem a gift to skeptics of climate change and opponents of climate policy. But Ritchie’s paper is a double-edged sword. The same finding that shrinks CO2 emissions may also lower the cost of dealing with global warming, making the Paris Agreement that addresses climate change easier to achieve.Although the study may lead to more well-informed models, it doesn’t necessarily indicate a brighter future for climate. Even low-end scenarios—in which emissions drop enough to limit warming to 3.6˚ F—would bring drastic changes to the climate system.
 

 
 Photo credit: <a href="https://www.flickr.com/photos/37467370@N08/7639182256/">Greg Goebel/Flickr (CC BY-SA)</a>
 

 
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We’ve Mistakenly Assumed That Coal Is Effectively Unlimited

It’s woven into clothing, spilling out of recycling bins, and floating in massive patches across the ocean. Plastic is everywhere—and now a global analysis of mass-produced plastic reveals that of the 8.3 billion metric tons of plastic created by 2015, 6.3 billion are already out of use. What’s more, most of it is in landfills and nature.Mass production of plastic began around 1950, and has since exceeded almost all other man-made materials. It hasn’t surpassed cement and steel, but the study’s authors point out that those materials are largely used in construction, providing decades of use. Plastics, on the other hand, mostly go toward short-term use.“Half of all plastics become waste after four or fewer years of use,” said Roland Geyer, associate professor of industrial ecology at the University of California, Santa Barbara, and lead author of the paper. The study, which was published in the journal Science Advances, looked at production, use, and lifetime data of polymer resins, synthetic fibers, and additives across eight industrial sectors.While plastics used in industrial machinery or construction regularly have lifespans exceeding 20 or 30 years, respectively, the largest market for plastic is packaging. And most plastic packaging is discarded in the same year it’s produced.Of the total plastic discarded by 2015, the researchers determined that 79% went into landfills or the natural environment, 12% was incinerated, and 9% was recycled. Recycling, they point out, only delays final disposal, and it’s unclear whether recycling actually prevents new plastic from being produced.“What we are trying to do is to create the foundation for sustainable materials management,” Geyer said. “Put simply, you can’t manage what you don’t measure, and so we think policy discussions will be more informed and fact based now that we have these numbers.”At the current rate, the researchers project that total plastic production will reach 34 billion metric tons by 2050, with total plastic waste reaching 12 billion metric tons. Mass-produced plastics do not biodegrade “in any meaningful way,” the authors note, pointing out that sunlight weakens plastic and causes it to break into tiny fragments known as microplastics. These fragments plague oceans and freshwater ecosystems alike—the same group of researchers estimated in a previous study that 8 million metric tons of plastic entered the ocean in 2010 alone.Increased research and media attention has led to some efforts to address the issue of plastics in water, and this month marks the beginning of a U.S. ban on <a href="http://www.pbs.org/wgbh/nova/next/earth/800-trillion-plastic-microbeads-go-down-drains-every-day/">plastic microbeads</a> commonly used in personal care products. But little is known about how plastics affect terrestrial ecosystems.
 

 
 Image credit: <a href="http://www.misawa.af.mil/News/Photos/igphoto/2000070915/">U.S. Air Force photo by Tech. Sgt. Phillip Butterfield</a>
 

 
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Recycling plastic only delays its eventual disposal.

76% of All Plastic Ever Made Has Already Been Discarded

Last week, an FDA panel unanimously <a href="https://www.nytimes.com/2017/07/12/health/fda-novartis-leukemia-gene-medicine.html">recommended</a> that the agency approve a treatment that genetically alters a patient’s immune cells to fight leukemia from within. This kind of “living drug,” called gene therapy, would be the first of its kind on the market in the United States if the FDA approves it.The treatment has to be created from scratch for each individual patient, using their own T cells—white blood cells used by the immune system. T cells are removed from patient’s bloodstream, then genetically engineered to recognize and kill cancer. The weaponized cells are then multiplied and reintroduced into the patient.Novartis, the company seeking approval for the first therapy, presented data from an 18-month study in which 52 out of 63 patients with B-cell acute lymphoblastic leukemia went into remission.The products that are closest to approval focus on blood cancers like leukemia and lymphoma, which represent about 80,000 of the 1.7 million cancer diagnoses in the United States each year. Here’s Denise Grady, reporting for The New York Times: “This has been utterly transformative in blood cancers,” said Dr. Stephan Grupp, director of the cancer immunotherapy program at the Children’s Hospital of Philadelphia and a professor of pediatrics at the University of Pennsylvania. “If it can start to work in solid tumors, it will be utterly transformative for the whole field.”Solid tumors are highly resistant to the kinds of altered T cells that have have proven effective against blood cancers. Although researchers are working on approaches for solid tumors, the challenge they present means that gene therapies may be further off for breast, ovarian, prostate, lung and pancreatic cancers, for example.But T-cell approaches aren’t the only thing out there. Researchers at the University of Texas MD Anderson Cancer Center are harnessing the power of so-called natural killer cells, another kind of immune cell that can be genetically altered to attack cancer. Unlike T cells, natural killer cells can be taken from cord blood donated at childbirth, and the modified cells can be safely given to multiple patients. What’s more, they have a kind of drug-activated “off switch,” which can be flipped in the event that the treatment causes unmanageable side effects.After “promising” studies in mice, the researchers have opened a study for patients with relapsed or treatment-resistant leukemia and lymphoma. The first patient is to be treated with the natural killer cell method this week.
 

 
 Photo credit: <a href="https://visualsonline.cancer.gov/details.cfm?imageid=2336">National Cancer Institute</a>
 

 
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Human cells with acute myelocytic leukemia.

'Living Drug' Therapies Could Revolutionize Cancer Treatment

Two new studies suggest that drinking coffee may extend your life. But you’d have to drink at least a cup a day—preferably three—and be OK with not knowing why coffee is correlated with longevity.
 

 
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 The health benefits were also the same regardless of whether the participants drank decaffeinated or regular coffee, suggesting that the benefit comes from coffee itself, not caffeine.The studies, both published today in the Annals of Internal Medicine, surveyed hundreds of thousands of adults aged 35 and up across a range of different ethnic groups in the United States and Europe.
 

 
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 One study tracked the habits of 521,330 people across ten European countries, and concluded that coffee drinking was associated with a decreased risk of mortality overall. It didn’t matter which disease they may have died from—or even if they were killed in an accident—coffee drinkers tended to die at a lower rate.The second study looked at 185,855 U.S. participants aged 45 to 75 and found that consuming two to three cups of coffee per day was associated with a reduced risk of heart disease, cancer, stroke, diabetes and respiratory, and kidney disease. The U.S. study included African American, Japanese American, Native Hawaiian, Latino and white participants, and found the effects to be similar across all groups except Native Hawaiians.The average follow-up period for both studies was 16 years, and researchers adjusted for factors such as age, sex, physical activity, education, and pre-existing disease.George Dvorsky, reporting for Gizmodo:
 

 
 

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 The researchers weren’t able to identify a causal relationship, nor were they able to explain why coffee appears to confer these health benefits. And importantly, some experts are challenging the conclusions reached in these two studies, saying the results were misleading, and that blanket statements about coffee consumption ignore the fact that, for some, caffeine is dangerous.
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 Other critics have pointed out that the studies didn’t account for different types of coffee, nor the concentration of coffee consumed, two factors that could alter the compounds found in the beverage.
 

 
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 In short, coffee might not be bad, as some reports have claimed, and it may even be good for you. Still, there are myriad variables in studies like this—far too many to control to the level scientists would need to make a definitive statement. So for now, drink coffee if you like, skip it if you don’t, and wait for the next study to be published.
 

 
 Photo credit: <a href="https://www.flickr.com/photos/publicplaces/7497483734/">David Hodgson/Flickr (CC BY 2.0)</a>

Across ethnic groups, both decaf and regular coffee were linked to health benefits.

Coffee may not make you immortal, but recent studies show a correlation between coffee consumption and longevity—even for decaf drinkers.

Robin Kazmier

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