Fatal sleeping sickness can spread through skin

December 19, 2016

London, Dec 19: Skin plays a significant role in harbouring and transmitting a parasite that causes African sleeping sickness - a condition which is often fatal if left untreated, a new study has found.flly

The study by researchers from the University of Glasgow in Scotland and the Institut Pasteur in France, may have a major impact on the way the disease is diagnosed, treated and potentially eradicated.

The disease, which kills thousands in Sub-Saharan African every year, is primarily transmitted to humans via the bite of an infected tsetse fly as it takes a blood meal, with diagnosis then confirmed through the presence of parasites in the blood.

The new study definitively shows that substantial quantities of trypanosomes that cause the disease exist within the skin and can be transmitted back to the tsetse fly vector, even in the absence of detectable signs of infection in the animal or detectable parasites in the blood.

The researchers were also able to observe the presence of parasites in human skin biopsies from individuals who displayed no symptoms.

The study's findings suggest skin-dwelling parasites may be sufficiently abundant in the skin to be ingested, transmitted and so able to spread the disease further.

"Our results have important implications with regard to the eradication of sleeping sickness," said Annette MacLeod from University of Glasgow.

"Firstly, our findings indicate that current diagnostic methods, which rely on observing parasites in the blood, should be re-evaluated and should include examining the skin for parasites," said MacLeod.

"In terms of treatment, it may also be necessary to develop novel therapeutics capable of targeting sources of infection outside the blood circulation and in the reservoirs underneath the skin," she said.

The findings also suggest the need for a re-evaluation of disease control policies.

The current policy of the World Health Organisation (WHO) is to avoid treating people who do not show any symptoms of sleeping sickness, unless parasites are detected in their blood, due to the long duration and high toxicity of the treatment, MacLeod said.

"This policy should be reconsidered in light of our compelling evidence that these patients represent a carrier population," she said.

"This is because their lack of treatment may help maintain disease outbreaks and explain previously thwarted efforts to eliminate this major pathogen," she added.

The study appears in the journal eLife.

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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
February 12,2020

Washington, Feb 12: People who are optimistic may contribute to the health of their partners, staving off the risk factors leading to Alzheimer's disease, dementia and cognitive decline as they grow old together, according to a study.

The research, published in the Journal of Personality, followed nearly 4,500 heterosexual couples from the US Health and Retirement Study for up to eight years.

The researchers found a potential link between being married to an optimistic person and preventing the onset of cognitive decline, due to a healthier environment at home.

"We spend a lot of time with our partners.They might encourage us to exercise, eat healthier or remind us to take our medicine," said William Chopik, an assistant professor at the Michigan State University in the US.

"When your partner is optimistic and healthy, it can translate to similar outcomes in your own life. You actually do experience a rosier future by living longer and staving off cognitive illnesses," Chopik said.

An optimistic partner may encourage eating healthy foods, or working out together to develop healthier lifestyles, the researchers said.

For example, if a person quits smoking or starts exercising, their partner is close to following suit, they said.

"We found that when you look at the risk factors for what predicts things like Alzheimer's disease or dementia, a lot of them are things like living a healthy lifestyle," Chopik said.

"Maintaining a healthy weight and physical activity are large predictors.There are some physiological markers as well. It looks like people who are married to optimists tend to score better on all of those metrics," he said.

The researchers said there is a sense where optimists lead by example, and their partners follow their lead.

They also suggest that when couples recall shared experiences together, richer details from the memories emerge.

Chopik noted while there is a heritable component to optimism, there is some evidence to suggest that it's a trainable quality.

"There are studies that show people have the power to change their personalities, as long as they engage in things that make them change," Chopik said.

"Part of it is wanting to change. There are also intervention programs that suggest you can build up optimism," he added.

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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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