The ability of the lens in the human eye to change focus relies on a dense formation of proteins that can result in clumps that cloud the lens and lead to cataracts – except for special protective proteins that prevent this. Now a team in Munich, Germany has discovered an activation mechanism that can switch on one of these protective proteins to keep the lens clear.

The team, from the Technische Universitaet Muenchen (TUM), writes about their findings in a recent online issue of the Proceedings of the National Academy of Sciences (PNAS).

They suggest the discovery may lead to alternative treatments for cataracts that do not require surgery.

Lens cells perform a remarkable feat. They produce a dense mix of proteins that give the lens its refractive power – its ability to change focus so we can see distant and close objects – yet at the same time keep the lens clear.

To overcome the problem of cloudiness, the lens cells produce and eliminate proteins in a completely different way to other cells – they make them once in the embryonic stage and preserve them for life. Unlike the proteins in the rest of our body, those in our lenses are as old as we are.

But to make the proteins last a lifetime, the lens cells have to keep them in a dissolved state, or they clump together and produce the cloudiness that is characteristic of cataracts.

And herein lies the clue to the German team’s discovery – they have found one of the mechanisms the cell uses to keep the proteins in a dissolved state for so long.

Two crystallin proteins stop other proteins clumping together

Scientists already knew that two related “heat shock” proteins, αA-crystallin and αB-crystallin, were involved. Heat shock proteins are present in all human cells and help stop other proteins clumping when the cell experiences strong heat or stress.

But until this study, little was known about the structure and behavior of the two crystallins, despite intensive research, as study author Johannes Buchner, professor for biotechnology at TUM, explains:

Molecular switch triggers the protective protein

A few years ago, scientists at TUM solved the mystery of one of the crystallin proteins – they decoded the molecular structure of one of the most important forms of αB-crystallin. The protein is made of 24 subunits.

Under normal conditions, when a lens cell is not stressed, the protein exists in the form that the scientists decoded. But they realized this is just a resting form, and not the form that helps prevent other proteins clumping. So they reasoned there must a switching mechanism that triggers the formation of active forms of the protein.

In the study they describe how they found the trigger – when the cell is exposed to stress, such as heat, phosphate groups attach to the crystallin protein causing it to break up into its subunits. Protein subunits bind to other proteins and stop them clumping. This is the active form of the crystallin.

The main challenge the team faced was resolving the structure of the protein, as co-author Sevil Weinkauf, professor for electron microscopy at TUM, explains:

The team believes their discovery of how the crystalline behaves could lead to new treatments for cataracts that do not require surgery. It may be possible to develop a drug that activates the αB-crystallin mechanism to clear up clouded lenses.

There could also be other applications, because the protein also plays a role in other cells. For instance it is too active in cancer cells and can stop them committing suicide. In that example, a drug could be developed to deactivate the protein.

Funds from the German Research Foundation helped finance the study.

In 2012, researchers at the Missouri University of Science and Technology in the US, found that eye drops containing an antioxidant can prevent or heal cataracts and other degenerative eye disorders.

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Researchers have revealed a new approach for treating human eye disease that has proved to be successful in preclinical studies. This is according to a study published in theJournal of Clinical Investigation.

The research team from The Scripps Research Institute (TSRI) in California, Mount Sinai Hospital in Canada and the University of California, San Diego (UCSD), say their findings could lead to new treatments to prevent blindness.

Many types of blindness, including diabetic retinopathy and macular degeneration, can be linked to the abnormal growth of blood vessels (neovascularization) in the retina at the back of the eye, the researchers explain. The retina is a thin layer of soft tissue consisting of blood vessels and light-sensing cells.

According to the Centers for Disease Control and Prevention (CDC), around 1.6 million Americans over the age of 50 suffer from macular degeneration, while 5.3 million people worldwide aged 18 or over have diabetic retinopathy, emphasizing the need for treatments for these diseases.

VEGF ’causes abnormal blood vessel growth’

In order to determine how the abnormal growth of blood vessels in the retina can be stopped, many studies over the last decade have focused on a molecule in the human body called vascular endothelial growth factor (VEGF).

The researchers explain that when the body senses too little oxygen, it triggers VEGF. Once the vessels in the eye sense high levels of VEGF, this causes them to produce more “shoots.”

Furthermore, VEGF and other molecules that prompt the growth of blood vessels, activate a gene called Ras that has to be triggered before new blood vessels can grow. Using this information, researchers believed that if VEGF can be stopped, this could potentially provide a cure for blindness.

However, research from the team at TSRI last year found that VEGF plays an important part in maintaining healthy vision. If VEGF were to be blocked, this could kill light-sensing cells in the eye, causing severe loss of vision.

This discovery meant researchers were now on the hunt for new ways to prevent abnormal blood vessel growth, and David Cheresh and colleagues at the Department of Pathology at UCSD found that microRNAs may be the answer.

MicroRNAs can ‘target’ blood vessel growth

Testing the theory on mice, the UCSD laboratory discovered that microRNAs – small pieces of RNA known to adjust gene activation and expression – could be used to target neovascularization in the VEGF pathway at a “downstream” point, preventing Ras activation.

This means that microRNAs are able to block the formation of abnormal blood vessel growth and still maintain the health of normal blood vessels in the eye.

Commenting on the findings, Prof. Martin Friedlander of the Department of Cell and Molecular Biology at TSRI, says:

Prof. Friedlander says it is hoped this approach will reach clinical trials. He notes that one pharmaceutical partner has already shown interest in teaming up with the research team once the therapy is advanced for human use.

However, he emphasizes that clinical trials could take many years, as the treatment needs to be proved safe and effective prior to routine availability.

“Are we ready to go to the clinic tomorrow? No,” adds Friedlander. “But is this class of therapeutics “drugable?” The answer is yes.”

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Black women may get less protection than whites from the vaccines recommended for preventing human papillomavirus (HPV), which causes cervical cancer, a new study suggests.

The currently available vaccines, Gardasil and Cervarix, don’t target the types of HPV infection found most often in black women, the study authors said.

Experts have long believed that most cervical cancers are caused by persistent infection with subtypes of the sexually transmitted virus known as HPV 16 and HPV 18. These are the strains targeted by Gardasil and Cervarix. (Gardasil also targets HPV 6 and HPV 11.)

But black women tend to develop cancer of the cervix — the lower part of the uterus or womb — and die from it more often than white women, even when screening programs are similar, according to background information included in the study. This led the researchers to wonder if blacks might be less likely to benefit from vaccination.

“HPV 16 and 18 occur less frequently in African-Americans than in whites,” said study researcher Cathrine Hoyo, associate professor of obstetrics and gynecology at the Duke University School of Medicine.

Hoyo’s team looked at women who had abnormal results on Pap tests — screenings to detect precancerous cervical abnormalities.

Of the nearly 600 women with Pap smear abnormalities in the study, about 86 percent had detectable HPV, Hoyo said.

“African-Americans had half the HPV 16 and 18 frequency as whites did,” said Hoyo, who is scheduled to present the findings Monday at a conference of the American Association for Cancer Research in National Harbor, Md.

The findings, if replicated in larger studies, could call into question the effectiveness of the current vaccines for all races, she said.

But women should still get an HPV vaccine, said Dr. Robert Morgan, co-director of the gynecological oncology program at the City of Hope Comprehensive Cancer Center in Duarte, Calif. “I don’t think recommendations on vaccination would change [based] on this data,” said Morgan, who was not involved in the research.

The American Cancer Society estimates that more than 12,000 new cases of cervical cancer will be diagnosed this year, and more than 4,000 women will die of the disease. Blacks are about 20 percent more likely to get cervical cancer, Hoyo said, and about twice as likely to die from it as white women.

The U.S. Centers for Disease Control and Prevention recommends HPV vaccination for preteen boys and girls at age 11 or 12, before sexual activity begins. The vaccines, given in three injections over a six-month period, cost about $400 or more

In developing Gardasil and Cervarix, scientists relied on studies to pinpoint the strains of HPV most likely to lead to cancer. Studies were done on all ethnicities, Hoyo said, noting that there may have been insufficient numbers of black women in the research studies to pick up the differences in HPV subtypes.

“There has always been some skepticism about whether there are other strains that are important, other than 16 and 18,” she said. This study is not the first to report the differences, she said.

The findings, however, are not a reason for blacks not to get an HPV vaccine, Hoyo said. Testing of vaccines that target additional HPV subtypes are under way, and in time the problem may be solved, she added.

Research presented at medical meetings should be viewed as preliminary until published in a peer-reviewed journal.

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Kombucha, an alcohol-free fermented beverage made from tea, might just be the next big thing in pro-biotics.

 Eric and Jessica Childs, who brought it forward, said that it has amazing benefits for gastrointestinal health and also has energizing properties.

In an attempt to promote the healthy drink, they started Kombucha Brooklyn, claiming that the drink is the perfect beverage for New Yorkers, the New York Daily News reported.

The husband-wife team has already experienced the benefits of Kombucha, which is a combo of tea, sugar, yeast and bacteria, said that the drink will boost immunity, improve digestion and relieve skin problems.

Eric said that when someone drinks Kombucha, they reap benefits from multiple microorganisms plus health benefits and flavour from the ingredients.

Jessica, a microbiologist with a certificate from the National Gourmet Institute, said that Kombucha can also be used in cooking as it has a large flavor profile.

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Researchers have found that hypoxia can be detected prior to the appearance of physical symptoms.

Jan Stepanek, M.D., the Aerospace Medicine Program Director and Co-Director of the Aerospace Medicine and Vestibular Research Laboratory, said that this study opens the door for objective assessments of hypoxia and additional safeguards for military and commercials pilots and others working in high altitudes.

Hypoxia is a lower than normal level of oxygen in your blood. To function properly, your body needs a certain level of oxygen circulating in the blood to cells and tissues.

When this level of oxygen falls below a certain amount, hypoxia can cause a variety of symptoms including shortness of breath, impaired speech, slowed reaction time and passing out.

The Mayo Clinic study team used the King-Devick neurocognitive performance test , commonly used to identify cognitive changes related to sports-related concussions, and to assess cognitive function under conditions of low oxygen-simulating altitude.

The King-Devick test assesses the time in viewing, identifying and reading aloud a series of numbers on three consecutive test cards. Based on test times of 25 participants, the study concluded that the King-Devick test is an effective tool to detect “impairment of cognitive performance at a presymptomatic stage of hypoxia.”

The findings have been published in journal Aviation, Space, and Environmental Medicine.

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A pledge by food manufacturers to cut saturated fat levels is “a drop in the ocean” in the fight against obesity, a top public health expert has said.

Morrisons, Subway and Nestle are among firms signed up to the voluntary “responsibility deal” between industry and government.

But Prof John Ashton, president of the Faculty of Public Health, said the approach “lacked credibility”.

The Department of Health (DoH) said it would “make a huge difference”.

It says the average man should eat no more than 30g of saturated fat a day, while the average woman should eat no more than 20g.

According to the British Dietetic Association, most people eat about 20% more than the recommended maximum levels – and a survey of 2,000 people for Sainsbury’s found 84% of those questioned did not know how much saturated fat was a healthy amount.

‘Healthy options’

The DoH said cutting the amount of saturated fat in people’s diets by 15% could prevent around 2,600 premature deaths every year from conditions such as heart disease and stroke.

Almost half of the food manufacturing and retail industry – based on market share – has signed up to this latest pledge to reduce the amount of saturated fat in products, the DoH said.

Measures planned by companies include Nestle altering the make-up of KitKat biscuits, Morrisons reformulating its range of spreads and Subway replacing biscuits and crisps in its Kids’ Pak with healthier options.

Other firms which are cutting saturated fat or have pledged to do so include Tesco, Sainsbury’s, Aldi and Mondelez International – which will alter products including its Oreo biscuits.

Prof Ashton said that, while it was “a good thing that some companies are making food that has less saturated fat than before”, the pledge did not go far enough.

“They need to ensure that at the same time they lower the sugar and salt that they have used to make foods tastier as a result of lowering the fat content.”

He added: “This announcement is a drop in the ocean in comparison with the scale of the obesity crisis.

“We cannot rely on the voluntary approach of the responsibility deal to solve this problem.

“It now lacks credibility and can be seen as a feeble attempt by the industry to save face.”

Labour public health spokeswoman Luciana Berger said: “A few company names on a non-binding plan with no timescale stands little chance of delivering the fundamental change needed to improve our national diet.

“In the week that the chief medical officer warned of the long-term dangers of childhood obesity, we need to go much further.”

She said Labour had put forward “bold ideas to set legal limits on our food’s fat, sugar and salt content and achieve a cross-party ambition for a more physically-active nation”.

‘Huge progress’

Tam Fry of the National Obesity Forum, also called for regulation, adding: “The much-vaunted voluntary responsibility deal will never succeed until the government takes a grip and makes everybody sign up to it.”

The DoH said that “by reducing the amount of saturated fat in everyday foods, manufacturers and retailers are helping us lead healthier lives”.

“We have already made huge progress through the responsibility deal – there are reduced salt levels in many products, calories on high street menus and better information about alcohol units and drinking guidelines,” a spokesperson said.

“We know there is more to be done but today’s pledge will make a huge difference to our health.”

Prof Susan Jebb, chairwoman of the Responsibility Deal Food Network, said the manufacturers’ commitments to help reduce saturated fat were “an important step forward”.

The announcement of the pledge comes days after cardiologist Aseem Malhotra, a member of the Academy of Medical Royal Colleges’ obesity steering group, wrote in the British Medical Journal that the risk from saturated fat in non-processed food was “overstated and demonized”.

He said there was too much focus on the fat with other factors such as sugar often overlooked.

He told Radio 4’s Today on Saturday that “a sugary drinks tax, banning junk food advertising to children, ensuring compulsory nutritional standards in schools and hospitals… are things that are going to overcome the problems that we face”.

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Tooth decay–although largely preventable with good care–is one of the most common chronic diseases of children ages 6-11 and teens ages 12 to 19. Tooth decay is five times more common than asthma and seven times more common than hay fever in children, according to the American Academy of Pediatrics. By kindergarten age, more than 40% of kids have tooth decay.

Start Oral Care Early

Your child should see a dentist by the time he or she is a year old, according to the American Academy of Pediatrics and the American Academy of Pediatric Dentistry. Getting preventive care early saves money in the long run, according to a report published by the Centers for Disease Control and Prevention. The report found that costs for dental care were nearly 40% lower over a five year period for children who got dental care by age one compared to those who didn’t go to the dentist until later.

Teach the Brush and Floss Habit

Dental visits are just part of the plan, of course. Tooth brushing is also crucial from the start. A lot of people think they don’t have to brush baby teeth. If your baby has even one tooth, it’s time to start tooth brushing. Even before you baby had teeth, you can gently brush the gums, using water on a soft baby toothbrush, or clean them with a soft washcloth. Once there are a few teeth present, buy an infant toothbrush that is very soft.(Be sure to use an approved toothpaste for your infants) Brushing should be done twice daily using a fluoridated toothpaste. Flossing should begin when two teeth touch each other. Parents should have an active role in brushing and flossing their childs teeth until the child has the proper dexterity to handle the tasks on their own. This is usually about the time a child can tie their own shoes.

Avoid “Baby Bottle Decay”

For years, pediatricians and dentists have been cautioning parents not to put an infant or older child down for a nap or to bed at night with a bottle of juice, formula, or milk. Even so, many parents don’t realize this can wreak havoc with their children’s oral health. The sugary liquids in the bottle cling to baby’s teeth, providing food for bacteria that live in the mouth. The bacteria produce acids that can trigger tooth decay. Left unchecked, dental disease can adversely affect a child’s growth and learning, and can even affect speech. If you must give your child a bottle to take to bed, make sure it contains only water, according to the American Academy of Pediatrics guidelines. Click here for more information on baby bottle decay.

Control the Sippy Cup Habit

Bottles taken to bed aren’t the only beverage problem, the other is juice given during the day as a substitute for water and milk. Often, that juice is in a sippy cup. It’s meant as a transition cup when a child is being weaned from a bottle and learning to use a regular cup. Parents mistakenly think juice is a healthy day-long choice for a beverage, but that’s not the case. Prolonged use of a sippy cup can cause decay, if the beverages are sugary. Juice consumption has been linked to childhood obesity and the development of tooth decay, according to the American Academy of Pediatrics. In its current policy statement on preventive oral health, the organization advises parents to limit the intake of 100% juice to no more than four ounces a day. Sugary drinks and foods should be limited to mealtimes. Most pediatricians are telling parents to use juice as a treat.

Ditch the Pacifier by 2 or 3

Long term use of a pacifier can be hazardous to dental health. Sucking too strongly on a pacifier, for instance, can affect how the top and bottom teeth line up (the bite) or can affect the shape of the mouth. Pacifiers are for infants, not for toddlers walking around with them in their mouths. Ideally, pacifiers should be dropped by age 2. The American Academy of Pediatrics suggests getting a professional evaluation if the pacifier habit continues beyond age 3.

Beware of the Unfriendly Mouth Medicines

Many medications that children take are flavored and sugary. If that sticks on the teeth, the risk for tooth decay goes up. Children on medications for chronic conditions such as asthma and heart problems often have a higher decay rate. Antibiotics and some asthma medications can cause an overgrowth of candida (yeast), which can lead to a fungal infection called oral thrush. You should suspect thrush if you see creamy, curd-like patches on the tongue or inside the mouth. If your child is on chronic medications, it is advised to help your child brush as often as four times a day.

Stand Firm on Oral Hygiene

Parents often say that their children put up a fuss when it comes time to brush and floss, so some parents relent and don’t keep up with oral care at home as they should. We advise these parents to let their children know they don’t have a choice about brushing and flossing and here are some tips to reward reluctant brusher’s and flosses to get the job done–or if they are too young, to allow their parents to help them do it.

•  Plan to help your children longer than you may think necessary. Most children don’t have the fine motor skills to brush their own teeth until about age 6. Flossing skills don’t get good until later–probably age 10.
•  Schedule the brushing, flossing and rinsing, if advised, at times when your child is not overly tired. You may get better cooperation.
•  Get your child involved in a way that’s age appropriate. For instance, you might let a child who is age 5 or older pick his own toothpaste in the store, from options you approve. You may also offer them a choice of toothbrushes, including kid friendly ones that are brightly colored and decorated.
•  Figure out what motivates your child; a younger child may gladly brush for a sticker. You may have to get a bit more creative for an older child.

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