Bacteria in Your Mouth Could Fuel Gut Diseases


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Bacteria in Your Mouth Could Fuel Gut Diseases

 https://www.livescience.com/60727-bacteria-mouth-gut-diseases.html
Bacteria in Your Mouth Could Fuel Gut Diseases

Credit: Concept Photo/Shutterstock

Bacteria that normally live in a person’s mouth could contribute to gut diseases such as inflammatory bowel disease (IBD), ulcerative colitis and Crohn’s disease, a new study in mice suggests.

The study found that, when certain strains of bacteria from the mouth make their way to the gut and settle down in the intestine, they can triggerchronic inflammation under certain circumstances.

The findings are preliminary and more research is needed to confirm the results in people. But if true, the study suggests that finding ways to target oral bacteria living in the gut could provide a new treatment for IBD and other gut diseases, the researchers said. [5 Ways Gut Bacteria Affect Your Health]

Previous studies have suggested that oral bacteria don’t typically live in a healthy person’s gut, because these bacteria are out-competed by other bacterial species already living in the gut. However, higher levels of oral bacteria have been found living in the guts of people with certain diseases, including IBD and colon cancer, the researchers said.

To further examine the link between oral bacteria and gut diseases, the researchers took saliva samples from patients with Crohn’s disease and IBD, and transplanted the sampled bacteria into mice bred to not produce their own gut bacteria (called germ-free mice). They found that a strain of bacteria in the saliva called Klebsiella pneumoniae could inhabit the intestines of the germ-free mice and activate types of immune cells known as “T helper cells,” which, in turn, can trigger an inflammatory response.

When the researchers inserted this strain of Klebsiella pneumoniae in another type of mouse with healthy or “balanced” levels of gut bacteria, K. pneumoniae couldn’t establish itself in the gut. But when these mice were fed certain antibiotics, K. pneumoniae could persist in the intestine, the researchers said.

What’s more, when the researchers gave K. pneumoniae to mice that were genetically prone to developing colitis (inflammation of the colon), they found that K. pneumoniae persisted in the mice’s intestines and caused severe inflammation.

These findings suggest that the K. pneumoniae strain can elicit “severe gut inflammation in the context of a genetically susceptible host,” the researchers from the Keio University School of Medicine in Japan wrote in the Oct. 20 issue of the journal Science.

The researchers next analyzed information from a database of the human “fecal microbiome,” which includes data on the types of bacterial DNA found in people’s poop. They found that people with Crohn’s disease and IBD had higher amounts of Klebsiella species in their poop, compared with healthy people.

The researchers hypothesize that, in people with IBD or other gut diseases, inflammation in the intestine may create an environment that is more hospitable to bacteria from the mouth. Once these oral bacteria (such asKlebsiella) colonize the gut, they may “help perpetuate gut microbiota dysbiosis [imbalance] and chronic inflammation,” the researchers said.

“Thus, our findings indicate that targeting oral-derived bacteria, particularly Klebsiella, could provide a therapeutic strategy to correct IBD and many other disease conditions,” the researchers wrote. One way to do this could be to identify “good bacteria” that could block Klebsiella from colonizing the gut, they said.

Original article on Live Science.

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Should People Who Can’t Quit Smoking Switch to E-Cigarettes?


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Should People Who Can’t Quit Smoking Switch to E-Cigarettes?

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Should People Who Can't Quit Smoking Switch to E-Cigarettes?

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Switching to e-cigarettes won’t solve all the health problems smokers face. For example, e-cigarettes are still addictive, and studies suggest that they may be bad for heart health. But compared with traditional tobacco cigarettes — which, in addition to nicotine, are full of tar and other toxins— e-cigarettes could be a less-risky option, a new study suggests.

Using mathematical models, researchers calculated how two possible scenarios of cigarette and e-cigarette use — one optimistic scenario and one pessimistic scenario — could impact public health if Americans who smoked cigarettes switched to e-cigarettes over the next 10 years.

The researchers noted that the study had several limitations. For example, the models are based on smoking uptake and quitting rates through 2012, but they do not account for the recent growth in e-cigarette use. In addition, the models included only cigarettes and e-cigarettes, and excluded other tobacco products, such as smokeless tobacco, according to the study. [4 Myths About E-Cigarettes]

The optimistic and pessimistic scenarios were based on a status-quo rate up to 2012 of smokers either quitting smoking altogether or switching to vaping. In the study’s “optimistic” model, the researchers assumed that more people stopped smoking tobacco cigarettes (primarily switching to e-cigarettes) and that the current scientific understanding that e-cigs aren’t quite as bad as cigarettes holds true. In that optimistic model, the researchers found that 6.6 million premature deaths could be avoided in the U.S., according to the study, which was published yesterday (Oct. 2) in the journal Tobacco Control.

Though one of the study authors has worked with both Pfizer and Johnson & Johnson, two manufacturers of smoking-cessation medications, this particular study was funded by the National Institutes of Health and did not receive any industry money, according to a statement.

In the study’s “pessimistic” model, the researchers assumed that fewer people gave up smoking than are doing so under the current rate and that the health risks of e-cigarettes turned out to be worse than scientists’ current understanding. In this case, only 1.6 million premature deaths were avoided.

The findings “support a policy strategy that encourages replacing cigarette smoking with vaping to yield substantial life-year gains” compared with cigarette smoking, lead researcher David Levy, an oncologist at Georgetown University Medical Center, said in a statement. In other words, switching from cigarettes to e-cigarettes could extend the lives of smokers, compared with if they were to continue smoking traditional tobacco cigarettes. [10 Tips to Help You Quit Smoking]

In addition to living longer than they would if they continued smoking tobacco cigarettes, those who switched to e-cigarettes might see other health benefits, “including reduced disease disability to smokers, reduced pain and suffering, and reduced exposure to secondhand smoke,” Levy said.

“Even the gloomiest analysis [the pessimistic model] shows a significant gain in years of life if nicotine is obtained from vaping instead of much more deadly amounts of toxicants inhaled with cigarette smoke,” Levy said.

Writing in an editorial that was published alongside the new study, Marita Hefler, a public health researcher at Menzies School of Health Research in Australia, said that “the health gains modelled [in the new study] show that even in a pessimistic scenario,” rapidly phasing out regular cigarettes could result in significant public health gains.

Original article on Live Science.

Diet of Lamb and Cheerios Leads to Boy’s Vision Loss


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Diet of Lamb and Cheerios Leads to Boy’s Vision Loss

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Diet of Lamb and Cheerios Leads to Boy's Vision Loss
These two photos show the patient’s eyes before treatment. In the photo on the left, the black arrows point to “Bitot spots,” which are raised, dry patches on the surface of the eye. The photo on the right shows changes to the boy’s cornea, which is the transparent layer at the front of the eye. Reproduced with permission from JAMA Pediatrics. 2017. doi:10.1001/jamapediatrics.2017.2543

Credit: Courtesy of the American Medical Association.

One boy’s vision problems and odd changes to his eyes turned out to be caused by a highly restrictive diet, according to a new report of the boy’s case from Canada.

The 11-year-old boy’s parents took him to the hospital after 8 months of progressively worsening vision, according to the case report, published Oct. 2 in the journal JAMA Pediatrics.

When doctors examined the boy, they found his vision was severely impaired: He could see hand motions only when they were within 12 inches (30 centimeters) of his face, said senior author of the case report Dr. Eyal Cohen, a pediatrician at The Hospital for Sick Children in Toronto who treated the boy. [27 Oddest Case Reports]

The outer layer of the boy’s eyes were also severely dry, Cohen told Live Science. This severe dryness can lead to a buildup of material in the cornea (the transparent outer covering of the eye), called Bitot spots, Cohen said.

The boy had multiple food allergies and eczema, according to the report. Because of concerns that certain foods could possibly trigger eczema outbreaks, the boy’s diet was limited to potatoes, pork, lamb, apples, cucumbers and Cheerios.

One thing those foods have in common? None are a good source ofvitamin A.

Indeed, when the doctors measured the levels of vitamin A in the boy’s blood, they found that he had a vitamin A deficiency. The boy’s blood levels of vitamin A were 14.3 micrograms per deciliter (ug/dL); the normal range for this vitamin is 25.8 to 48.7 ug/dL, according to the report. Cohen said the boy’s deficiency was severe.

Vitamin A deficiency is very common in poorer parts of the world, where it is a leading cause of blindness,” Cohen said. But in more developed parts of the world, it is rarer, he said. Still, “people who have highly restricted diets like the child in this case report are at higher risk of [vitamin A deficiency] and other nutritional deficiencies.”

Vitamin A is essential for vision, as it helps certain cells in the eyes function properly, according to the case report. Not getting enough of the vitamin can lead to abnormalities in the retina, Cohen said. The retina, found at the back of the eye, is home to light-sensing cells that make vision possible.

To treat the boy’s vitamin deficiency, he was given intravenous “megadoses” of vitamin A daily for two days, consisting of 200,000 IU, followed by a third dose 2 weeks later. (A normal dose of vitamin A for an 11-year-old boy is 2,000 IU daily, according to the Mayo Clinic.)

Six weeks later, the appearance of the boy’s eyes had significantly improved, according to the report.

This is a photo of the boy's eye after his treatment for vitamin A deficiency. The eye has returned to a normal appearance. Reproduced with permission from JAMA Pediatrics. 2017. doi:10.1001/jamapediatrics.2017.2543
This is a photo of the boy’s eye after his treatment for vitamin A deficiency. The eye has returned to a normal appearance. Reproduced with permission from JAMA Pediatrics. 2017. doi:10.1001/jamapediatrics.2017.2543

Credit: Courtesy of the American Medical Association.

His vision improved a lot as well, Cohen said, to 20/800 vision in both eyes. Cohen noted that this level of visual impairment may not be completely corrected by wearing glasses. Anything beyond 20/200 vision is considered legally blind, according to the American Foundation for the Blind. In some cases, vision loss linked to vitamin A deficiency can be reversed, but in the boy’s case, a degree of loss is likely permanent, according to the report.

The boy’s parents are taking steps to ensure that he gets enough vitamin A daily. Good sources of vitamin A include carrots, sweet potatoes, leafy green vegetables and fish, according to the report.

Originally published on Live Science.

Hepatitis A Spreads Through San Diego: Why It’s So Hard to Stop


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Hepatitis A Spreads Through San Diego: Why It’s So Hard to Stop

Hepatitis A Spreads Through San Diego: Why It's So Hard to Stop

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SAN DIEGO — More than 480 people in San Diego have become infected with hepatitis A over the last 10 months, in the largest outbreak of the illness in California in decades. But why is it so hard to stop?

About 20 new cases of hepatitis A per week have been reported during this outbreak, Dr. Eric McDonald, director of San Diego County’s Epidemiology and Immunization Services Branch, said at a news conference here yesterday (Oct. 5), part of an infectious diseases conference called IDWeek 2017. Most of the hepatitis A cases have been among people who are homeless or use illegal drugs, or who have close contact with those populations. Of the 481 people who have been infected, 337 (70 percent) have been hospitalized and 17 (4 percent) have died, officials said.

Dr. Monique Foster, of the Centers for Disease Control and Prevention’s (CDC) Division of Viral Hepatitis, said it’s not uncommon for large hepatitis A outbreaks like this to last a long time — around one to two years — before they are completely halted.

Though the hepatitis A virus isn’t typically deadly, it can infect the liver and cause inflammation and damage to that organ, according to the National Institutes of Health (NIH). Symptoms can include dark-yellow urine, fever, joint pain, nausea and vomiting. People with the infection usually get better on their own without treatment, the NIH says. But in some cases, the infection can lead to liver failure, particularly in older adults or people who have other liver diseases. [27 Devastating Infectious Diseases]

Hepatitis A spreads when small amounts of stool from an ill person contaminate objects, food or drinks that another person then touches and ingests. This can happen when people with the illness don’t properly wash their hands after going to the bathroom, according to the CDC. In San Diego, officials have installed 66 portable handwashing stations in the streets to address the hygiene issue, with 100 more stations on the way. The virus can also spread among drug users, also through poor hygiene when sharing equipment related to illicit drug use.

One reason specialists and doctors have a hard time stopping the spread of hepatitis A is its long “incubation period” — the time it takes a person to show symptoms after he or she is infected — which lasts on average 28 days. But it can be up to 50 days, Foster said.

“People infected today probably won’t show symptoms for four weeks,” Foster said. This makes it hard for people to recall what they were doing, or who they had contact with, at the time they were exposed to hepatitis, Foster said, and both of those factors help officials track and control outbreaks. It also means people who don’t yet appear sick can infect others, causing more cases.

In addition, the long incubation period means that by the time officials notice a cluster of hepatitis A cases, the outbreak has likely been going on for at least a month, Foster said. And once officials do identify an outbreak, it can take six weeks to determine whether efforts to control the outbreak are working, McDonald said.

Another challenge in the San Diego outbreak is the specific population at risk for contracting hepatitis A in this outbreak: people who are homeless or who use illicit drugs. This is a population that has limited access to clean toilets and handwashing facilities, which are important to preventing the spread of hepatitis A.

Additionally, vaccination with the hepatitis A vaccine is one of the key ways to prevent the infection, the CDC says. But in the current outbreak, it took time to get these vaccinations to the groups at risk for the disease, McDonald said. To get vaccines to this “target” group, officials used unique strategies, including administering vaccines in emergency rooms, where it is easier to track down homeless people, and jails, where illicit drug users may be vaccinated before they end up back on the streets, officials said. Officials also established teams of people to go to homeless encampments and administer vaccinations.

“It takes time to set up systems in order to deliver vaccines,” McDonald said. “I think those systems are [now] strongly in place here to address the ongoing outbreak.”

As of Sept. 30, more than 54,000 adults in the area had been vaccinated against hepatitis A as part of the efforts to stem the current outbreak, McDonald said.

In general, the hepatitis A vaccine is recommended for children at age 1; travelers to countries that have high rates of hepatitis A; users of illegal drugs; people with chronic liver diseases, such as hepatitis C; men who have sexual contact with other men; and people who work with animals infected with hepatitis A, according to the CDC.

Prior to the San Diego outbreak, the hepatitis A vaccine was not specifically recommended for people who are homeless, but now, the state of California is recommending that this vaccine be given to the homeless population. CDC officials will also consider whether this should become a national recommendation, Foster said.

Original article on Live Science.

Sprains: Causes, Treatment & Prevention


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Sprains: Causes, Treatment & Prevention

Sprains: Causes, Treatment & Prevention

People who are involved in sports are more likely to injure their ligaments, though anyone can experience a sprain.

Credit: And-One/Shutterstock

A sprain happens when the ligaments of the body become stretched or torn. A ligament is a fibrous band of tissue that connects the bones at a joint. This is why sprains are localized around joints such as ankles, knees and shoulders.

Normally, the ligament can expand and snap back into place when a person moves. Sometimes, though, the ligament is pushed beyond its normal capabilities and causes a sprain. Any joint can be affected by a sprain if the ligament is suddenly pushed, twisted or impacted. The most common type of sprain is an ankle sprain, according to the Mayo Clinic.

People who are involved in sports are more likely to injure their ligaments, though anyone can experience a sprain. For example, if someone stumbles and catches the fall with their hands, they can sprain their wrists. Twisting a knee while dancing, running or just going up a flight of stairs can cause a knee sprain. A person can even sprain fingers and thumbs.

Symptoms of a sprain include a popping sound during the injury, bruising, pain, swelling and limited movement for the affected joint.

A sprain can also lead to long-lasting health problems. For example, a sprain in the wrist can lead to carpel tunnel syndrome (CTS). Symptoms of CTS can start with nighttime numbness or tingling, along with hand pain and those affected should seek medical attention, according to Dr. Shari Liberman, a hand and upper extremity orthopedic surgeon at Houston Methodist Hospital. “Usually, the patient will wake up at night with those symptoms and has to shake out their hands to relieve the pain,” said Liberman. “The symptoms can progress to daytime numbness or tingling and pain.”

A sprained ankle can get bruised and swollen.

A sprained ankle can get bruised and swollen.

Credit: J HIME/Shutterstock


Sprains and strains have many of the same symptoms, but they are not the same thing. A strain is when a tendon stretches or tears, while a sprain affects ligaments. Tendons are cords of tissue that connect bones to muscles in the body.

Whiplash is a condition that often involves both sprains and strains. Whiplash is any injury of the neck’s soft tissues resulting from forced movement, often caused by a car accident. It can affect muscles, joints, discs, nerves, ligaments and tendons, according to the National Institute of Neurological Disorders and Stroke. Whiplash is often classified as a secondary injury of a concussion, Kenneth Podell, a neuropsychologist at Houston Methodist Hospital, told Live Science.

A medical professional typically performs a physical inspection of the injured area to look for symptoms of a sprain. Magnetic resonance imaging (MRI) may be used to see determine how badly the ligament is affected. If the bone could be broken, the medical professional may order an X-ray.

There are three types of sprains, rated by their severity. According to the American Academy of Orthopaedic Surgeons the three types of strains are:

  • Grade 1 sprain (mild): This includes a slight stretching and some damage to the fibers of the ligament.
  • Grade 2 sprain (moderate): This includes the partial tearing of the ligament.
  • Grade 3 sprain (severe): This involves a complete tearing of the ligament.

Mild sprains usually only need time to heal, rest and a little care. Remember the RICE procedure: rest, ice, compression and elevation. Over-the-counter pain reliever such as ibuprofen (Motrin IB, Advil) or acetaminophen (Tylenol) can be used to lessen the pain, and ice packs can be applied to reduce swelling. An ice pack should be placed on the area 20 minutes four to eight times a day, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. The area should also be elevated and compression should be applied using a compression bandage.

In more severe cases, a medical professional may immobilize the area with a brace. If there is a torn ligament or ruptured muscle, surgery may be needed to correct the problem, according to the Mayo Clinic.

Muscle training, stretching and stability training are all important steps to preventing strains because they keep the muscles strong and flexible. A medical professional should be consulted for the best exercises. The medical professional will take into consideration the type of sports and activities an individual is interested in for the best training recommendation.

Warm-up exercises, such as light jogging, before a strenuous activity can also help avoid sprains. Also, avoid running, exercising or playing a sport when tired or in pain.

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New Gene Therapy for Blindness: How Does It Work?


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New Gene Therapy for Blindness: How Does It Work?

New Gene Therapy for Blindness: How Does It Work?

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A new gene therapy may soon be approved to treat a rare genetic form of vision loss and blindness. But how does it work?

Tomorrow (Oct. 12), a panel of advisers for the Food and Drug Administration (FDA) will consider whether to approve the therapy, called Luxturna. It is made by the biotechnology company Spark Therapeutics.

Luxturna is intended to help people who have mutations in a gene called RPE65, which is responsible for making a protein found in the retina (the light-sensitive cells at the back of the eye) that is critical for normal vision. People inherit two copies of the RPE65 gene, but if both of the copies have mutations, those people experience progressive vision loss starting in infancy, according to Spark Therapeutics. At first, patients may lose their peripheral vision and develop “tunnel vision,” and they may also have trouble seeing in dim light. But eventually, they may lose their central vision as well and become totally blind, Spark Therapeutics said. [Unraveling the Human Genome: 6 Molecular Milestones]

RPE65-related eye diseases affect an estimated 1,000 to 3,000 people in the United States, the company said. Currently, there are no drugs to treat these diseases.

The gene therapy works by giving patients a working copy of the RPE65 gene. The researchers placed this gene inside a modified virus that is not harmful to people, and this “vector” delivers the gene to the retinal cells. Doctors administer the therapy during a procedure that involves injecting the modified virus into patient’s eyes.

In a recent study of Luxturna, conducted by Spark Therapeutics, the researchers gave the drug to 20 patients with a condition called Leber congenital amaurosis (LCA), an eye disease that results from RPE65 mutations. This group was compared to nine patients with LCA who did not receive Luxturna (called the “control group.”)

One year after the treatment, 18 of the 20 participants (90 percent) who received the therapy showed improvement in their ability to navigate a maze in low to moderate lighting conditions, Spark Therapeutics said. And 13 of the 20 participants were able to navigate the maze under the lowest light conditions, the researchers said. In contrast, none of the participants in the control group was able to navigate the maze under the lowest lighting conditions.

Because patients in the study were followed only for a year, it’s unclear how long the effects last. However, some patients in earlier studies of the drug have been followed for several years, and these patients have maintained their initial improvements, Spark Therapeutics said.

Although Luxturna was only tested in patients with LCA, it’s thought the drug may be helpful to patients with other diseases caused by RPE65 mutations, the researchers said.

If Luxturna gets the green light from the FDA, it would be the first time a gene therapy for an inherited disease has been approved in the United States, according to Reuters.

Original article on Live Science.

A Beautiful Illustration of Something Quite Horrible


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A Beautiful Illustration of Something Quite Horrible

Two Zika particles at work (Image: David S. Goodsel/RCSB Protein Data Bank)

Up until a few months ago, we knew virtually nothing about the Zika virus—or what it even looked like. But a beautiful new illustration by David S. Goodsell reveals its hidden details, while also showing how the dreaded virus goes to work.

Scientists have been hard at work trying to untangle the mystery that is the Zika virus this year. The pathogen was discovered in Uganda back in 1947, but it wasn’t considered dangerous. Things have changed after Zika was linked to birth defects, and the virus is now propagating through parts of South and Central America at epidemic levels.

The Zika virus has been officially linked to microcephaly, a condition in which fetal brains grown abnormally small, as well as Guillain Barre syndrome, a rare disorder that causes temporary paralysis. Insidiously, Zika can breach the placental barrier and disrupt the development of the fetal brain.

Two Zika particles at work (Image: David S. Goodsel/RCSB Protein Data Bank)

Back in May, cryo-electron microscopy finally uncovered the virus’s appearance. In the artistic rendering above, molecular biologist David S. Goodsell from the Scripps Institute used color and shape to convey the virus’s appearance and function.

The spherical structures (shown in pink) represent a pair of Zika virus particles in a blood vessel filled with blood plasma cells (tan). Both particles are on the verge of penetrating a cell (blue), and they’re binding to the cell’s protein receptors (green).

The virus at the bottom right is a cross section of a Zika particle. The illustration shows viral proteins (red) protruding like studs from its outer surface, with membrane proteins (pink) embedded within a fatty layer of lipids (light purple). These studs, of which there about 180, protrude from the particle, allowing it to bind itself to certain human cells, including antibodies and host receptors. This also explains why the virus can attack nerve cells and critical cells required for normal fetal development. The viral genome itself can be seen deep inside the particle (yellow) coiled around capsid proteins (orange).

Zika is actually quite similar in appearance and function to other flaviviruses, such as dengue, West Nile, and yellow fever. This is actually good news, because it means that ongoing efforts to create vaccines for these related viruses could be applied to Zika.

[NIH]