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Gene therapy for malaria: Benefits far outweigh the risks

Gene therapy for malaria: Benefits far outweigh the risks

There’s a new treatment emerging for malaria, a kind of gene therapy that makes the malaria parasite more susceptible to anti-malaria drugs. It’s the work of a team at Yale University, whose lead researcher, Sidney Altman, is famous as a pioneer in molecular genetics. In 1989, he won the Nobel Prize for his discovery that RNA molecules can function as enzymes, understanding of which changed everything in genetics along with research on the origins of life. Now, Altman’s team at Yale believes it’s possible to alter genetic expression of plasmodium, the malarial parasite, which could amount to a sea change in the war against one of humanity’s worst infectious diseases.

And so, there’s no way that anyone could be against it, right? Well maybe not. After all, it is a kind of gene therapy and gene therapy scares people, especially those who do not like scientists messing with anyone’s genome. Of course they don’t all say “genome”. Typically, the alarmists say “genetic code”. That’s what you find in the most alarmist articles, like this one on the quack website Natural News, where Mike Adams, the same guy who recently blamed Beau Biden’s death on GMOs and chemotherapy, wrote:

I’d like to talk about genetic engineering for a moment, but to preface it with the recognition that we, as a society, are nowhere near the level of maturity and ethics required for manipulating the genetic code. I don’t believe we are ready for genetic engineering, but at some point we may evolve ethically and spiritually to the point where we can more responsibly grasp this potential technology. So even though I’m in favor of exploring genetic engineering in the long run, I am solidly against it today.

It’s almost as if Adams said, “I’m genetically illiterate, but hear me out anyway.” Otherwise, he would know that the Genetic Code is not a target of gene therapy. But that’s okay; the Genetic Literacy Project is all about facilitating literacy about things that people need to know to navigate issues of biotechnology, things like what is a gene, what is DNA, what is RNA, and what is the Genetic Code.

So let’s talk about why “Genetic Code” is capitalized when used correctly, yet is not capitalized when used by those who don’t know what they’re talking about. The Genetic Code is the language that all living things on Earth–all cells in the human body and any organisms that make humans sick–use to read genes in order to express them. It’s not the content that varies from species to species and individual to individual. There are genes coding for the Code itself, but those are the genes that do not get changed. All organisms of all species use the same genetic language, but differ in the genetic content that the language is used to express. Thus, for example, the plasmodium parasite, uses the exact same Genetic Code that our cells use.

The Genetic Code has been around for billions of years. It has not evolved much, and it’s needed for genes to work and for gene therapy to work.  And so, while initially it may sound as if we’re merely being picky about terminology, it’s actually about understanding the most important concept in genetics. But get ready to hear more from those concerned about gene therapy, especially from alarmists like Adams who fundamentally don’t trust modern medicine, mainstream doctors, and scientists.

The question that comes up now though is whether we have ‘evolved ethically’ enough to commit to defeating malaria, which kills 500,000-800,000 people, mostly children and mostly in third world countries. Now, because of our exponentiating ability to manipulate, not the Genetic Code but genes and gene products within cells, the Yale team has a novel strategy that may be poised to turn the tides against malaria.

Gene therapy for malaria: How it works

Before delving into the therapy, it’s important to talk about what malaria is and why it’s such a problem. Plasmodium is a kind of protozoan, a singled-celled creature whose structure and genetics are very similar to those of our own cells. Several species of plasmodium act as parasites in humans. Victims get infected with plasmodium through a mosquito bite and the organism settles in the liver. There, it matures and reproduces for 3-12 days, depending on the species. During this time the victim has no symptoms and for certain plasmodium species this state can continue for a few years. In most cases, however, new immature forms of the parasite spread out from the liver and infect red blood cells and that’s when the person gets really sick, with a very high fever, chills, fatigue, and a host of other symptoms. Certain drugs can destroy plasmodium parasites, but there’s been growing resistance to the drugs, especially from the worst plasmodium species, called Plasmodium falciparum. Additionally, many of the antimalarial drugs will destroy the parasites in blood cells, but not those remaining in the liver, so the person can get sick again.

In a new study published in the Proceedings of the National Academy of Sciences, Altman’s team from Yale demonstrated how to use specially designed strands of RNA called a morpholino oligomers to strike directly at P. falciparum, where the punch can have the greatest effect: the parasite’s gene expression. Before a gene in DNA in the cell nucleus can be translated –using the language of the Genetic Code that is the same in all organisms– into a protein that’s needed to run a specific function in the cell, the gene is first transcribed into what’s called messenger RNA (mRNA).

The mRNA is a kind of intermediate that must travel to a different part of the cell before the genetic message can finally be used. But a specially designed morpholino oligomer can attach to the mRNA, effectively neutralizing it, or it can interfere with how the mRNA is spliced or otherwise processed in order to deliver its message. Thus, while the gene in the nucleus may be switched on so that it’s constantly sending out it’s message, the message cannot be read, so whatever protein was supposed to be manufactured never does get manufactured. It’s kind of like RNA interference that’s being used ever more frequently to design new foods.

Since this all happens inside the cells of the parasite, the morpholino oligomer strategy can potentially be far more effective than any drug, if certain key genes are chosen for blocking. Or, the Yale research suggests, morpholino oligomer can be used to weaken the parasite, such that strains otherwise resistant to antimalarial drugs would become extremely susceptible.

Could there be risks? Of course there could be. To be delivered to plasmodium parasites in red blood cells, liver, and other tissues, morpholino oligomers would have to be sent through the infected patient’s blood and people might worry that they might do something to the patient’s own cells. Well they might, but then again, they are RNA, not DNA. RNA does not last very long before it’s broken down, so there’s no reason to think that a morpholino oligomer should have any permanent  effect on a human. Perhaps, they could block expression of a human gene that happens to be very similar to a plasmodium gene. But such an unlikely effect would be very temporary, and all in all the most susceptible entity within the person would be the parasite that the morpholino oligomer is designed specifically to kill. So while there’s a risk, it’s very small, and that must be considered, particularly in context of one of humanity’s worst diseases.

David Warmflash is an astrobiologist, physician and science writer. Follow @CosmicEvolution to read what he is saying on Twitter

Retrieved from: http://www.geneticliteracyproject.org/2015/10/25/gene-therapy-for-malaria-benefits-far-outweigh-the-risks/

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Do you like Sushi? Think again!

Do you like Sushi? Think again!

If you have read and relished the supposed diets of lit-from-within celebrities, you know what you risk when you see a nutritionist. When I visited a widely recommended expert downtown last week to report frequent nausea and acid reflux that need not be elaborated on, I expected she would insist I make some modifications to what I eat. I was willing! Prepared! Short of a colonic, I was enthusiastic about it all.

She first told me to eliminate dairy—​a bedfellow, she said, of inflammation and catastrophe. She banned gluten and red meat next, breaking it gently to my gut that it would be better off without bread or brisket. When she prescribed probiotics and a chelated iron supplement, I nodded, swearing to follow what was sure to be a routine of sewer-scented all-natural pills. But when she proposed that I stop eating raw fish, I froze.

I love sushi—​fancy sashimi and the spicy tuna rolls that I once found at a 24-hour market in Boston both. It is a superlative food and my best and most basic treat.

“It’s hard, because we think fish is so good for us,” the nutritionist said, sympathizing. “But, really, I’d put raw fish up there with dairy and gluten. For your gut, it’s a killer.”  She explained that uncooked fish makes for a cozy home for parasites and chemicals, which can eat away at your digestive tract and probably kill you. Better to grill it or bake it and stick to a straightforward cucumber-avocado roll at your local Haru. I pretended to understand what I would have to give up in that tiny office of abstemiousness. But I was not convinced.

“The reported dangers of illness brought on by eating raw fish and meat often cause fear and confusion in the minds of those who enjoy such food, either for their esthetic or nutritional benefits,” wrote Mimi Sheraton, speaking my truth in the New York ​Times ​in 1981. She went on to cite a then-recent report that recommended that “public health education should discourage the eating of raw and inadequately prepared fish or squid,” which would have caused me greater angst were it not more than three decades out of date. I resolved to seek more current wisdom.

I discovered that “public health education” had decided it better to legislate raw fish than disavow it. The New York City Department of Health and Mental Hygiene published a new round of regulations this summer that mandate that fish served raw or marinated raw must be flash frozen in order to be served, killing parasites in the process. The move, which has reduced some toro devotees to tears, only validates what many kitchens already do. A representative for the New York State Restaurant Association told the New York ​Times ​that fish is often frozen at some point in production to preserve freshness, anyway, which is bureaucratic speech for: Get over it.

It’s not only the suits who support the guidelines. Naomichi Yasuda, owner of the revered Sushi Yasuda, has imported and then frozen fresh tuna for at least a decade. The late Nobu 57 chef Shin Tsujimura reported that even he could not “tell the difference between fresh and frozen in a blind test.”

The method is almost foolproof—​if perhaps not essential. An expert in the virulent nature of Manhattan-born unease, Mount Sinai Gastrointestinal Motility Center director Dr. Gina Sam told me that the parasites eliminated by a quick cool are not even very common in the United States. “If you have a normal digestive system and the fish is prepared in a clean environment,” she says, “you should be okay.”

Nutritionist Dana James weighed in too, explaining that while raw fish is a more likely to be a breeding ground for bacteria and parasites than cooked fish, the precautions that restaurants take are proven to minimize risk. ​​”Should you avoid sushi? Not necessarily,” James says. “Just remember we are constantly exposed to pathogens, and they rarely cause havoc in the body, but when they do you know it! Your stomach becomes bigger than your boobs!”  Besides, James adds, “I love fluke crudo too much to give it up.”​

Pointing to recent recalls of spinach and cucumbers, New York-based nutritionist Amy Shapiro reasons that garden vegetables can be as perilous as undercooked or raw fish. Chipotle scrambled to switch tomato suppliers earlier this year when it discovered that a bad batch of the juicy fruits had caused a salmonella outbreak in Minnesota. Hysteria so overwhelmed customers in the state that a Department of Health spokesman had to eat a “fully loaded burrito bowl” just to prove that all was well. Brave man. Listeria outbreaks have forced companies like Jeni’s Splendid Ice Cream and Blue Bell to shut down production.

Nu-Train nutritionist Heather Bauer gave this final reassurance to rescue me from the brink. “For a healthy person,” Bauer says, “the risks are so small they’re just not something I worry about.” While she advises patients with compromised immune systems to opt for a seared salmon over a zippy ceviche, Bauer sees no need for me to renounce it. “When someone feels sick when they eat sushi, I always want to know, ‘Did you use a ton of soy sauce? Did you eat a lot of edamame?’ The fish might not be problematic, but the gluten in soy sauce or just the soy in something like edamame can be an irritant.”

“Try a squeeze of lemon over your sushi for that hit of acid, if you want,” she tells me, treating me very much like the addict I am. “See how it feels.”

So bolstered, I consider whether I want to sneak down to Whole Foods for a salmon-avocado roll for lunch. But visions of tapeworms stall me. I know whom I have to consult. I visit goop.com and search for raw-fish recipes.

A description of tuna poke seals the deal. While her royal goopness cautions that “eating raw fish of unknown provenance and freshness can always be a little dubious,” she declares that she is “totally on board” with the raw-fish dish. Elsewhere, she extols the virtues of “omega-3 fatty acid packed fish” and deems the protein “great for those on a cleanse.” Sushi—​it probably won’t kill you, might just make you stronger.

Source: http://www.elle.com/culture/travel-food/news/a31044/is-your-sushi-killing-you/

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When Butterflies Shouldn’t Fly Free

When Butterflies Shouldn’t Fly Free

Take a look at Twitter or any other social media platform, and you’ll see photo after photo of people excitedly and passionately releasing captive-bred monarch butterflies at weddings, class expeditions, and other public events.

The photos are pretty powerful, and the people obviously think they’re doing something important to help these imperiled insects.

According to scientists, however, these releases may be doing more harm than good.

It turns out that many captive-bred monarchs carry diseases, most notably a monarch-killing parasite called Ophyrocystis elektroscirrha, which is closely related to ones that cause malaria and toxoplasmosis. The diseases spread easily at large “monarch farms,” which raise thousands of the butterflies at a time and sell them for release around the country to help their wild cousins.

Monarch populations have plummeted 90 percent over the past two decades, and the United States Fish and Wildlife Service is considering a petition to protect the iconic insect under the federal Endangered Species Act. Scientists have linked the rapid decline of the species to industrialized agriculture in the Midwest, where the widespread planting of genetically modified crops and the skyrocketing use of pesticides have wiped out milkweed, the sole food source for monarch caterpillars.

A letter signed by 10 noted monarch researchers last week said they have observed mass monarch die-offs from the diseases since 2004—which is around the same time that the practice of releasing large numbers of captive-bred monarchs began to become popular.

“Disease can build up in farmed monarchs, which can then spread to wild butterflies,” Sonia Altizer, a professor at the University of Georgia and leading researcher on monarch diseases, said in a statement. “Even monarchs that survive to adulthood can still carry and spread infections, placing already reduced populations of wild monarchs at greater risk.”

Mark Hunter, a professor of ecology and evolutionary biology at the University of Michigan who has been studying monarchs for 20 years, said the problem is similar to diseases that appear on poultry farms and spread through the closely packed population. “You can’t take organisms like monarchs, rear them up in huge densities like this, and not expect to see some kind of evolution,” he said. “The parasite can get more and more and more virulent.”

This increased virulence makes the diseases more dangerous for wild monarchs, Hunter said: “If somebody releases all of these butterflies with these incredibly virulent parasites, they are now available to attract wild insects that have had no recent evolutionary relationship with that virulent parasite.”

RELATED: The U.S Approves a Powerful New Pesticide Deadly to Monarch Butterflies

Hunter was not among the scientists who signed last week’s letter, but he coauthored a paper published this week that found that monarchs’ ability to withstand these parasitic infections is closely related to milkweed plants.

Milkweed, it turns out, is more than just the monarchs’ favorite food. It’s also their pharmacy. Previous research has shown that mother butterflies that are infected with the parasites lay their eggs on the most toxic milkweed plants to provide medicine to hatching, hungry larvae. The new research now links that medicinal toxicity to certain naturally occurring fungi in the soil. Plants that grow in soils that contain the fungi become more toxic to the parasites and therefore more beneficial to the butterflies.

That doesn’t mean that every milkweed plant can or should be treated with the fungi to prevent the spread of diseases. Hunter said that would be like giving all human children a dose of penicillin when they are born. “We’re going to get incredible selection for antibiotic-resistance, and suddenly everyone’s going to be in hospital with these multiple resistant bacteria,” he said.

The scientists are not calling for an end to all monarch releases, but they do advise keeping them small and using caution. “If someone really wants to raise monarchs for educational purposes, then we suggest that they collect caterpillars from nearby—such as within the same county—bring them inside to raise them, then let them go when they are adults,” said Sarina Jepsen, endangered species program director for the Xerces Society for Invertebrate Conservation, the organization that issued last week’s letter.

Some educators already do that. Dave Hogg, a professor at the University of Wisconsin–Madison and past president of the Entomological Society of America, said a release conducted in his class last month used butterflies raised from hand-collected eggs and small larvae. He called the parasites that may be present in other commercially raised monarch releases “a great example of unintended consequences of actions for people with good intentions.”

Jepsen and Hunter said raising and releasing monarchs should not be considered a strategy for boosting butterfly populations. “If people want to help monarchs, we recommend that they create, enhance, or restore monarch habitat with native milkweed and other nectar-producing flowers,” Jepsen said. “It’s a ‘build it and they will come’ framework.”

Hunter added, “What we really want to encourage the public to do is whenever they have opportunity, find out what’s native their area, plant those milkweeds, and make sure the soil is in good condition. If we reestablish native plant communities with native fungi, you’ll have that natural pharmacy, and you’ll let the organisms themselves work it out.”

Original Source: http://news.yahoo.com/butterflies-shouldnt-fly-free-230009217.html

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Think Twice Before Sending Your Kids To Play In The Sandbox

Think Twice Before Sending Your Kids To Play In The Sandbox

Kids love sandboxes, but so do animals, bacteria, and parasites. Not all sandboxes out there are dangerous, but you may want to at least check a sandbox before you let your child dive into its mysterious contents.

I certainly spent a fair amount of time battling ants in my backyard sandbox as a kid, but had I known what could be in there, I may have let the ants have it. Melinda Wenner Moyer at Slate investigated a number of studies that show how dirty dirt can really be:

…public health-testing organization NSF International sampled 26 different items in public places-toys at doctors’ offices, children’s library books, playground sandboxes-for a 2008 study on germs, they found that sandboxes were far and away the germiest of all, harboring nearly 2,000 times more bacteria, yeast, and mold per square inch than the door handles of public restrooms.

That’s pretty gross, but germs aren’t the end of the world for kids who are building up their immune systems. Unfortunately, there’s more:

…other microbial gifts that sandboxes sometimes leave for kids: parasitic worms. Like giant litter boxes, uncovered sandboxes invite animals-raccoons, dogs, cats-to use them as bathrooms, which essentially turns them into giant parasite Petri dishes.

These parasites can include the parasitic worm Ascaris, the cat-spread Toxoplasma gondii, the dangerous Toxocara, and the raccoon-spread Baylisascaris procyonis (in which one-third of cases are fatal). Before you shun sandboxes completely, however, it’s important to know that cases of dangerous parasitic infection are usually pretty rare. Furthermore, there are a few things you can do to help keep your kids safe on the playground. Cover your sandboxes at home when they’re not in use to keep animals out, keep your kids out of sandboxes that smell bad, and do your best to keep your kids’ hands clean and out of their mouth during and after play (hand sanitizer won’t kill parasitic worm eggs, so wash with soap and water). The whole article is well worth a read, so learn more about sandbox safety at the link below.

Original Source: http://www.lifehacker.co.in/life/Think-Twice-Before-Sending-Your-Kids-to-Play-in-the-Sandbox/articleshow/49425617.cms

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What Happens When You Get A Parasite

What Happens When You Get A Parasite

Original Source: http://indefinitelywild.gizmodo.com/what-happens-when-you-get-a-parasite-1732054948

The experience of living with a stomach parasite is not something a decent person would ever want to share. Which brings me to the point of this article: the parasites I contracted in Guatemala.

My bowels were bleeding, my intestines sounded like a rockslide, I was diuretic, bloated and weak. So, I had some reason to believe I may have contracted a slight stomach bug.

After a lifetime on the road, I recently settled for a little while in Quetzaltenango, Guatemala — an average town in the developing world, simultaneously a remnant of the past and a glimpse into the future of civilization. Nature and tribal traditions yet to be covered by concrete; hot, steaming and lawless. Violence, disease, debris and dystopia; it’s a jungle out here.

I’m not sure if my previously sturdy disposition is the result of surviving exposure or existed in spite of it. It was probably just luck. In the Belizean jungle, I complained about the sand flies, but they did me no real harm while my friend Robert contracted Leishmaniasis from them. In West Africa, a fly laid an egg in an open burn on my leg (contracted in a motorcycle crash), resulting in a staph infection that did me no real harm, but which nearly killed my partner when she simply touched it.

Now though, my luck had run out and something inside me was letting me know it.

I could have tried antibiotics, like in the civilized world or simply swallowed a whole cigarette, like in Vietnam, but both cures seems like too much of a scorched earth tactic. Strangely, it’s somewhat sad to think about killing parasites living inside you for, in a primal way, they feel like progeny, blooming in your stomach. An immaculate male maternity, maybe. Perhaps it’s fitting that we get to suffer them just like our environment suffers the human species.

Having a parasite may make you feel like a badass, but it also makes your ass feel bad. A trip to the clinic in a backwater country frequently results in misdiagnosis. But I was curious to find out what it was, and there’s nothing quite like standing in line with a bunch of Mayan mamas cradling fragrant stool samples in old jars.

My friend Colocho worked at the clinic, along with some American volunteer babes I knew, so I handed those my jar. “Come back after lunch and we’ll have your results,” said a dimpled intern. Chicks dig scars. Who digs parasites?

“You have an amoeba,” they announced on my return.

“Oh yeah? Everyone has those,” said my climbing buddy Denise.

“This one chick, she pretty much had her brain swiss cheesed by amoebas and had to fly to Europe to get her head blasted by radiation,” Kevin recalled.

For less than a dollar, the clinic sold me some sketchy pills about which I could find no information online. They were those no-name pills that are sold only in developing countries. And I wasn’t going to fall for that; obviously a WHO conspiracy to sterilize the masses. Nothing that cheap could possibly be healthy. So, I decided to explore natural alternatives.

Don’t get me wrong, I’m a big believer in medicine. I’ll take a dollop of vaccine-induced autism over Typhoid or Meningitis any day of the week. But most lesser diseases don’t have a silver bullet vaccine and treatment of them by western medicine can be expensive and bring serious side effects. I’m particularly wary of antibiotics; undeniably over-prescribed and inarguably deadly to the billions of good organisms my gut needs to help me fight the bad guys.

So, I ate papaya seeds and raw garlic like they were popcorn. I cut pork from my diet, drank gallons of strong black tea and even made efforts to keep the big, dirty labrador named Ramona out of my bed. I wore long sleeves and pants to avoid mosquitoes, figuring Chikungunya would only compound my problems.

Little by little, the symptoms went away. I’m back to feeling 100 percent and, indisputably, a better, smarter, wiser traveler for the experience. Now, where can I find a taco truck?

 

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Head lice myths and treatment

Head lice myths and treatment

Original Source: http://www.cbc.ca/news/canada/calgary/head-lice-myths-treatment-1.3238904

Do you feel something crawling along your scalp? Are you sure? What’s that itchy sensation on your head?

Head lice is one of the ickiest things you’re likely to find on someone’s noggin, and one that many families will face as children head back to school. They will also likely face many myths about the blood-sucking parasites.

One that’s making the rounds is the theory put out by a couple of U.S. doctors that teenagers are spreading lice thanks to putting their heads together for selfies.

“I think they’ve forgotten their own teenage years. Teens like being together in close proximity doing other things than selfies,” said Dr. Raj Bhardwaj, adding lice don’t move that quickly.

He also threw cold water on the idea that lice would migrate from one’s head to a hat or toque, although if someone he knew had lice offered him a head cover, he’d “politely decline despite the scientific evidence.”

Head lice are a picky species, adapting to become a strictly human parasite that only settles for blood sucked from a scalp.

“They have evolved over millennia to be very specific human parasites. So they don’t infest dogs or cats or any other kind of animal — it’s only humans. And not only that, it’s only human heads. There are body lice and pubic lice, which are different subspecies,” said Bhardwaj.

There’s also not a sudden metamorphosis into some kind of super mutant being, despite some social media accounts.

That said, the parasites have been evolving thanks to the natural selection tied to our chemical warfare — we kill them off, so only those who survive the treatments reproduce.

What to do?

So if you do feel like something is skittering across your head (itching comes later if untreated), the best thing to do is look at treatments based on silicone that attack the exoskeleton of lice, or to go old fashioned and go through your hair, or your child’s hair, with a fine toothed comb.

“Do the physical labour of getting this out,” said Bhardwaj. “It’s really gross and it takes a lot of time and your kids have to be patient and you have to be patient and you have to do it more than once.”

And what about keeping your kid out of school for seven days if they have lice?

“Absolutely not, no,” said Bhardwaj, adding you should change their behaviour to reduce contact with classmates.

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