Knowledge Update

​London, Oct 2 (IANS) Excessive sugar consumption -- specifically the sugar fructose such as in soda -- has been linked to a rise in metabolic disease worldwide, a study has found.

Some investigators contend that commonly consumed amounts of sugar do not contribute to this epidemic. While others are convinced that excessive sugar ingestion is a major cause.

"There is still significant controversy as to whether sugar consumption is a major contributor to the development of diabetes," said senior author Mark Herman, Assistant Professor at Duke University.

However, "the study reveals a specific mechanism by which consuming fructose in large amounts, such as in soda, can cause problems", Herman added.

Insulin is a key hormone that regulates blood glucose after eating. Insulin resistance, when the body's metabolic tissues stop responding normally to insulin, is one of the earliest detectable changes in the progression to diabetes.

The likely cause of insulin resistance may not be the build-up of fat in the liver, as commonly believed, but may be caused by excess sugar in the liver that activates a molecular factor known as carbohydrate-responsive element-binding protein, or ChREBP.

ChREBP may then contribute to the development of both fatty liver and increased glucose production, the researchers said.

The ChREBP protein is found in several metabolic organs in mice, humans and other mammals.

"We found that no matter how much insulin the pancreas made, it couldn't override the processes started by this protein, ChREBP, to stimulate glucose production. This would ultimately cause blood sugar and insulin levels to increase, which over time can lead to insulin resistance elsewhere in the body," Herman explained.

To test their hypothesis, researchers studied mice that were genetically altered so their liver insulin signalling pathways were maximally activated -- in other words, their livers should not have been able to produce any glucose.

The researchers found that even in these mice, eating fructose triggered ChREBP-related processes in the liver, causing it to make more and more glucose, despite insulin signals telling it to stop.

Previous studies have reported that high fructose diets can cause multiple metabolic problems in humans and animals, including insulin resistance and fatty liver disease.

The finding could also help scientists one day diagnose metabolic disorders earlier on, potentially allowing patients to make changes to their diets and lifestyles sooner to prevent more serious complications.

The study published in the Journal of Clinical Investigation.

Sydney, Oct 2 (IANS) Researchers have found three-dimensional prints of a 400 million year old fish fossil that can reveal the possible evolutionary origins of human teeth.

The printed fish fossil was found around Lake Burrinjuck in southeast Australia, by researchers from The Australian National University (ANU) and Queensland Museum in Australia.

The team digitally dissected the jaws of a fossil Buchanosteus -- an armoured fish from the extinct placoderm group -- and used the 3-D prints to learn how the jaws moved and whether the fish had teeth.

"We are conducting further research on the internal tissue structure of tooth-like denticles in the mouth of the fish fossil, to determine whether they represent a transitional stage in the evolution of teeth," said Gavin Young, palaeontologist at The Australian National University (ANU).

In the study, the team used high-resolution CT scan to investigate the internal structure of very fragile fossil skulls and braincases that have been acid-etched from limestone rock.

"It's great that we are able to use recent technology, such as micro-CT scanning and 3-D printing, to examine some of the earliest known evidence of tooth-like structures in the most primitive jawed fishes," noted Carole Burrow from Queensland Museum.

The study helped determine when and how teeth -- a characteristic feature of all animal species with jaws, including humans -- had originated in evolutionary history.

The results were published in the journal Biology Letters.

​London, Oct 2 (IANS) Family history and environment of the residential area are responsible for the differences between individual immune systems, a study has found.

The study published in the journal Trends in Immunology, discusses what shapes our immune system and how it might be applied.

The study has shown that air quality, food, stress levels, sleep patterns, and lifestyle choices had a strong combined effect on immune responses.

"Diversity isn't just programmed into our genes -- it emerges from how our genes respond to the environment," said Adrian Liston, researcher at the Translational Immunology Laboratory, Belgium.

Long-term infections are responsible for most of the differences between individual immune systems. 

These interactions slowly change the cellular makeup of immune system and make it more sensitive to that specific virus but also easier for other infections to slip past its defences. 

"People without these infections don't experience these cellular changes and even with the occasional cold or fever, their immune systems stay relatively stable over time. The exception is when a person is elderly," Liston added.

Researchers have shown that ageing changes how our immune system responds to threats. 

According to the study, as one gets older an organ called the thymus gradually stops producing T cells, which are made to help to fight off infection. Without new T cells, older people are more likely to get sick and less likely to respond to vaccines.

Beyond T cells, ageing also seems to broadly change the way our immune systems react. 

"A lot of diseases that we associated with ageing have an inflammatory component, which suggests there is likely immune involvement," said Michelle Linterman, researcher at the Babraham Institute, Britain.

"Understanding how the immune system changes with age is going to be hugely important for treating age-related diseases in the future," Linterman added. 

Mumbai, Oct 4 (IANS) Beauty brand Dove on Tuesday marked its entry in the baby care category by announcing the launch of Baby Dove in India.

Actress Genelia Deshmukh and TV show host Tara Sharma unveiled the product range here.

​New Delhi, Sep 28 (IANS) As we enter a technology era where Next-Gen devices are launched every single day, some are bound to fail as they don't connect with consumers -- while a few will be remembered as being ahead of their time. So what exactly went wrong with two recent much-hyped devices: Google Glass and Samsung Galaxy Note 7?

​London, Oct 1 (IANS) In an another attepmt to take on photo sharing mobile service Snapchat, Facebook has rolled out a new feature called Messenger Day which lets users post photos and videos that disappear after a day.

Washington, Oct 1 (IANS) Homeopathic teething tablets and gels may pose a health risk to infants and children, the US Food and Drug Administration (FDA) has warned.

Consumers should stop using these products and dispose of any in their possession, FDA recommended on Friday. 

Homeopathic teething tablets and gels are distributed by CVS, Hyland's, and possibly others, and are sold in retail stores and online, the US drug regulator said in a statement.

Following the FDA's warning, CVS announced a voluntary withdrawal of all brands of homeopathic teething products sold in its retail stores and online at CVS.com.

"Consumers should seek medical care immediately if their child experiences seizures, difficulty breathing, lethargy, excessive sleepiness, muscle weakness, skin flushing, constipation, difficulty urinating, or agitation after using homeopathic teething tablets or gels," FDA said.

"Teething can be managed without prescription or over-the-counter remedies," said Janet Woodcock, Director of the FDA's Center for Drug Evaluation and Research. 

"We recommend parents and caregivers not give homeopathic teething tablets and gels to children and seek advice from their health care professional for safe alternatives," Woodcock noted.

The FDA is analysing adverse events reported to the agency regarding homeopathic teething tablets and gels, including seizures in infants and children who were given these products, since a 2010 safety alert about homeopathic teething tablets. 

The FDA is currently investigating this issue, including testing product samples.

​Toronto, Oct 1 (IANS) Researchers in Canada have developed two caffeine-based chemical compounds that show promise in preventing the ravages of Parkinson's disease.

Parkinson's disease attacks the nervous system, causing uncontrolled shakes, muscle stiffness, and slow, imprecise movement, chiefly in middle-aged and elderly people. 

It is caused by the loss of brain cells (neurons) that produce dopamine, an essential neurotransmitter that allows neurons to "talk" to each other.

The team from University of Saskatchewan focused on a protein called Alpha-synuclein (AS), which is involved in dopamine regulation.

In Parkinson's sufferers, AS gets misfolded into a compact structure associated with the death of dopamine-producing neurons. 

"Many of the current therapeutic compounds focus on boosting the dopamine output of surviving cells, but this is effective only as long as there are still enough cells to do the job," said one of the lead researchers Jeremy Lee from University of Saskatchewan College of Medicine.

"Our approach aims to protect dopamine-producing cells by preventing AS from mis-folding in the first place," Lee noted.

Although the chemistry was challenging, Lee explained the team synthesised 30 different "bifunctional dimer" drugs, that is, molecules that link two different substances known to have an effect on dopamine-producing cells. 

They started with a caffeine "scaffold," guided by literature that shows the stimulant has a protective effect against Parkinson's.

From this base, they added other compounds with known effects -- nicotine, the diabetes drug metformin, and aminoindan, a research chemical similar to the Parkinson's drug rasagiline.

Using a yeast model of Parkinson's disease, Lee and his team discovered two of the compounds prevented the AS protein from clumping, effectively allowing the cells to grow normally.

"Our results suggest these novel bifunctional dimers show promise in preventing the progression of Parkinson's disease," Lee said.

The findings were published in the journal ACS Chemical Neuroscience.

Beijing, Sep 30 (IANS) Concerned over falling iPhone sales and the phenomenal rise of Chinese smartphone players, Apple has set up its first research and development centre in China with the initial investment of 100 million yuan ($15 million).

New York, Sep 30 (IANS) Leading a healthy lifestyle can shorten the time that is spent disabled near the end of one's life by nearly two years, says a study.

Older adults with the healthiest lifestyles could expect to spend about 1.7 fewer years disabled at the end of their lives, compared to their unhealthiest counterparts, the findings showed.

"The duration of the disabled period near the end of one's life has enormous personal and societal implications, ranging from quality of life to health care costs," said senior author Anne Newman, Professor at University of Pittsburgh Graduate School of Public Health in the US.

"We discovered that, fortunately, by improving lifestyle we can postpone both death and disability. In fact, it turns out that we're compressing that disabled end-of-life period," Newman noted.

The findings, published online in the Journal of the American Geriatrics Society, are based on analysis of a quarter century of data.

Newman and her colleagues examined data collected by the Cardiovascular Health Study, which followed 5,888 US adults for 25 years.

All of the participants were aged 65 or older and were not institutionalised or wheelchair-dependent when they enrolled.

The participants reported or were assessed for various lifestyle factors, including smoking habits, alcohol consumption, physical activity, diet, weight and their social support system.

The researchers took into account and adjusted results for such factors as participants' age, sex, race, education, income, marital status and chronic health conditions.

Across all the participants, the average number of disabled years directly preceding death -- years when the person had difficulty eating, bathing, toileting, dressing, getting out of bed or a chair, or walking around the home -- averaged 4.5 years for women and 2.9 years for men.

For each gender, those with the healthiest lifestyle (those who were nonsmokers of a healthy weight and diet and getting regular exercise) not only lived longer, but had fewer disabled years at the end of their lives, the study said.