Human hair-inspired body armour in the offing

January 18, 2017

Los Angeles, Jan 18: Scientists have found why human hair is incredibly strong and resistant to breaking, a finding that may lead to new generation of materials for body armours and even help create better hair care products.

hairHair has a strength to weight ratio comparable to steel. It can be stretched up to one and a half times its original length before breaking, researchers said.

"We wanted to understand the mechanism behind this extraordinary property," said Yang Yu, a PhD student at the University of California San Diego.

"We're interested in understanding the correlation between the structure and the properties of biological materials to develop synthetic materials and designs - based on nature - that have better performance than existing ones," said Marc Meyers, a professor at UC San Diego.

Researchers examined at the nanoscale level how a strand of human hair behaves when it is deformed, or stretched. The team found that hair behaves differently depending on how fast or slow it is stretched. The faster hair is stretched, the stronger it is.

"Think of a highly viscous substance like honey. If you deform it fast it becomes stiff, but if you deform it slowly it readily pours," said Meyers.

Hair consists of two main parts - the cortex, which is made up of parallel fibrils, and the matrix, which has an amorphous (random) structure.

The matrix is sensitive to the speed at which hair is deformed, while the cortex is not. The combination of these two components, Yu explained, is what gives hair the ability to withstand high stress and strain.

As hair is stretched, its structure changes in a particular way. At the nanoscale, the cortex fibrils in hair are each made up of thousands of coiled spiral-shaped chains of molecules called alpha helix chains.

As hair is deformed, the alpha helix chains uncoil and become pleated sheet structures known as beta sheets. This structural change allows hair to handle up a large amount deformation without breaking.

This structural transformation is partially reversible. When hair is stretched under a small amount of strain, it can recover its original shape. Stretch it further, the structural transformation becomes irreversible.

"This is the first time evidence for this transformation has been discovered," Yu said.

"Hair is such a common material with many fascinating properties," said Bin Wang, a UC San Diego PhD alumna.

The team also conducted stretching tests on hair at different humidity levels and temperatures. At higher humidity levels, hair can withstand up to 70 to 80 per cent deformation before breaking. Water essentially "softens" hair - it enters the matrix and breaks the sulphur bonds connecting the filaments inside a strand of hair.

Researchers also found that hair starts to undergo permanent damage at 60 degrees Celsius. Beyond this temperature, hair breaks faster at lower stress and strain.

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Agencies
May 18,2020

China, where the novel coronavirus originated, has reported 111 cases since beginning of May, which shows the infection rate has dipped, and 3 deaths since April 27, according to the WHO. A Shanghai-based Noida doctor says China is close to winning the battle against COVID-19, and the combination of zinc, hydroxychloroquine (HCQ) and antibiotic azithromycin has been able to save the lives of coronavirus patients.

Speaking to media persons, Dr Sanjeev Choubey, Medical Director Internal Medicine at St. Michael Hospital said this combination has been adopted as a line of treatment for patients infected with coronavirus, and as a result patients are recovering, decreasing their need for intensive care.

What is the line of treatment for COVID-19 patients, which also include asymptomatic patients?

The combination of zinc, hydroxychloroquine and antibiotic azithromycin has produced positive results, and it helped in the recovery of many COVID-19 patients. The combination -- Ascorbic Acid, B-complex, Zinc, Selenium, L-carnitine, Vitamin B-12 and Glutathione normal saline should be administered on patients twice a week for at least 6 weeks. This is COVID-19 treatment protocol for prophylaxis, and it implies both asymptomatic and symptomatic along with other medicine support.

Based on your experience on COVID-19 in China, after how many tests, is it safe to call a person coronavirus free?

The coronavirus should be performed at least 9 times, before terming a patient COVID-19 free. It is a standard in China. This procedure has worked in China and it will also work in India. Minimum five tests should be mandatory through RT-PCR.

Does coronavirus majorly attack the respiratory system or it could lead to organ failure too?

Line of treatment should not be just looking at the respiratory system, as the problem lies somewhere else. COVID-19 attacks many vital organs in the body. In China, a coronavirus patient died from a stroke. In the autopsy it was found that the innermost layer in the arteries was swollen. It was concluded that coronavirus had inflamed the layer of the arteries leading to clotting, which was a factor in generating a heart attack. Therefore, COVID-19 is not just a respiratory problem.

Amid the coronavirus pandemic, should autopsy be made mandatory in the case of unpredictable death or where reasons for death are not unknown?

Patients below 50 years, who die suddenly and the reasons are not known, then it should be mandatory to conduct the autopsy. After death, coronavirus is active in the body for five days, and it fades away on day 6. Therefore, if an autopsy is done then it will help in understanding this disease. In China, we have seen young COVID-19 patients, aged 22 and 28, succumbed to strokes.

Since the beginning of May, India has recorded more than 2,000 cases everyday in the first week, then it jumped past 3,000 mark in the second week. Finally, the tally is 4,987 on May 17. At 90,927 cases, has India progressed into community transmission or Stage3?

Yes, India has moved into Stage 3. The data suggests that 3,000 to 4,000 active COVID-19 cases, who are asymptomatic, are moving around and spreading the infection. The research has indicated that COVID-19 from an infected person spreads in 30 minutes to non-infected persons. The relaxation on the lockdown will certainly contribute to a high infection rate.

Do you think India has reached its peak in COVID-19 cases, or the sharp rise will continue till July end?

It seems India has already reached its peak and cases will begin to come down from June end or beginning of July first week. If social distancing norms are followed then certainly things can improve, but if not followed then it may get worse. High population density is a major contributor for the increase in cases. The government should continue to focus on finding hotspots, and urge people to follow the rules, eventually it is for people’s own benefit.

Has China won the battle against COVID-19?

It seems China has won the battle by not opening up Wuhan. The Chinese are following a COVID-19 patient’s engagement program, where the authorities continuously interact with people infected with the disease. The Government of India should reward people who follow the guidelines; it will help in setting up a positive trend in the society.

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Agencies
February 6,2020

Researchers have found the rates of lung cancer are higher in young women than men.

The study, published in the journal Pediatrics, examined lung cancer rates in young adults in 40 countries across five continents and uncovered a trend of higher lung cancer rates in women compared with men in recent years.

The emerging trend was widespread, affecting countries across varied geographic locations and income levels.

The changes appeared to be driven by a rising rate of adenocarcinoma lung cancer among women, said the study researchers from University of Calgary in Canada.

Lung cancer rates have been higher among men than women because men started smoking in large numbers earlier and smoked at higher rates; however, recent studies have reported converging lung cancer incidence rates between sexes.

Among men, age specific lung cancer incidence rates generally decreased in all countries, while in women the rates varied across countries with the trends in most countries stable or declining, albeit at a slower pace compared to those in men.

For the findings, lung and bronchial cancer cases between 30-64 age group from 1993-2012 were extracted from cancer incidence in five continents.

The study found the higher emerging rates of lung cancer in young women compared to young men.

According to the researchers, future studies are needed to identify reasons for the elevated incidence of lung cancer among young women.

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News Network
May 13,2020

California, May 13: A fasting-mimicking diet could be more effective at treating some types of cancer when combined with vitamin C, suggests a new study conducted by the scientists from USC and the IFOM Cancer Institute in Milan.

In studies on mice, researchers found that the combination delayed tumour progression in multiple mouse models of colorectal cancer; in some mice, it caused disease regression. The results were published in the journal Nature Communications.

"For the first time, we have demonstrated how a completely non-toxic intervention can effectively treat an aggressive cancer," said Valter Longo, the study senior author and the director of the USC Longevity Institute at the USC Leonard Davis School of Gerontology and professor of biological sciences at the USC Dornsife College of Letters, Arts and Sciences.

"We have taken two treatments that are studied extensively as interventions to delay ageing-- a fasting-mimicking diet and vitamin C -- and combined them as a powerful treatment for cancer," added Longo.

The researchers said that while fasting remains a challenging option for cancer patients, a safer, more feasible option is a low-calorie, plant-based diet that causes cells to respond as if the body were fasting.

Their findings suggest that a low-toxicity treatment of fasting-mimicking diet plus vitamin C has the potential to replace more toxic treatments.

Results of prior research on the cancer-fighting potential of vitamin C have been mixed. Recent studies, though, are beginning to show some efficacy, especially in combination with chemotherapy.

In this new study, the research team wanted to find out whether a fasting-mimicking diet could enhance the high-dose vitamin C tumour-fighting action by creating an environment that would be unsustainable for cancer cells but still safe for normal cells.

"Our first in vitro experiment showed remarkable effects. When used alone, fasting-mimicking diet or vitamin C alone reduced cancer cell growth and caused a minor increase in cancer cell death. But when used together, they had a dramatic effect, killing almost all cancerous cells," said Longo.

Longo and his colleagues detected this strong effect only in cancer cells that had a mutation that is regarded as one of the most challenging targets in cancer research.

These mutations in the KRAS gene signal the body is resisting most cancer-fighting treatments, and they reduce a patient's survival rate. KRAS mutations occur in approximately a quarter of all human cancers and are estimated to occur in up to half of all colorectal cancers.

The study also provided clues about why previous studies of vitamin C as a potential anticancer therapy showed limited efficacy. By itself, a vitamin C treatment appears to trigger the KRAS-mutated cells to protect cancer cells by increasing levels of ferritin, a protein that binds iron.

But by reducing levels of ferritin, the scientists managed to increase vitamin C's toxicity for the cancer cells. Amid this finding, the scientists also discovered that colorectal cancer patients with high levels of the iron-binding protein have a lower chance of survival.

"In this study, we observed how fasting-mimicking diet cycles are able to increase the effect of pharmacological doses of vitamin C against KRAS-mutated cancers," said Maira Di Tano, a study co-author at the IFOM, FIRC Institute of Molecular Oncology in Milan, Italy.

"This occurs through the regulation of the levels of iron and of the molecular mechanisms involved in oxidative stress. The results particularly pointed to a gene that regulates iron levels: heme-oxygenase-1," added Tano.

The research team's prior studies showed that fasting and a fasting-mimicking diet slow cancer's progression and make chemotherapy more effective in tumour cells while protecting normal cells from chemotherapy-associated side effects. The combination enhances the immune system's anti-tumour response in breast cancer and melanoma mouse models.

The scientists believe cancer will eventually be treated with low-toxicity drugs in a manner similar to how antibiotics are used to treat infections that kill particular bacteria, but which can be substituted by other drugs if the first is not effective.

To move toward that goal, they say they needed to first test two hypotheses: that their non-toxic combination interventions would work in mice, and that it would look promising for human clinical trials.

In this new study, they said that they've demonstrated both. At least five clinical trials, including one at USC on breast cancer and prostate cancer patients, are now investigating the effects of the fasting-mimicking diets in combination with different cancer-fighting drugs.

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