Science and Technology Archives - Page 4 of 12

July 26, 2011July 26, 2011

‘Dirty sock smell’ Lures Mosquitoes to a Sticky End

Researchers in Tanzania have chemically reproduced the stench of smelly feet in an innovative new approach to combat the spread of malaria in the country.

The scientific team at Tanzania’s Ifakara Health Institute has developed a potent serum — similar to that of human foot odor — to lure and kill mosquitoes, which can carry malaria and other diseases.

Four times more powerful in attracting mosquitoes than natural human odor, the synthetic smell is now being used in a pioneering research program aimed at killing mosquitoes outdoors using a “mosquito landing box.”

“The goal is to eliminate malaria,” said scientific researcher, Fredros Okumu, who is developing the technology. “We are going to do this by tackling the transmission of disease outside the house.”

Mosquitoes are lured inside the boxes by the synthetic odor, which is dispersed by a solar-powered fan. Once inside, the insects are either trapped or poisoned and left to die.

“We know mosquitoes don’t see people, they smell them.” Okumu said.

“Substances we omit when we sweat, such as lactic acid, act as a signal to mosquitoes … The aim here was to produce a mixture that would mimic a human being.”

The result, said Okumu, was a chemical blend that “smelt just like dirty socks.”

“If you came to our lab when the research was being done, you would have thought that someone had just come off a soccer field,” he admitted.

Okumu, who is currently completing a PhD from the London School of Hygiene and Tropical Medicine, in England, plans to develop the mosquito landing boxes over the next two years, thanks to a $775,000 joint grant from the Bill and Melinda Gates Foundation and the not-for profit organization Grand Challenges Canada.

“This is a great example of an African innovator, with an African innovation, tackling an African problem,” said Dr Peter Singer, CEO of Grand Challenges Canada.

“Malaria kills about 800,000 people a year, mostly children, in Africa. At the moment existing technologies, such as bed nets and sprays, tend to repel mosquitoes inside the home.

“This technology attracts mosquitoes outside the home to kill them, and could be complimentary to what is there now,” Singer continued.

Working closely with villagers in remote communities where malaria is endemic, Okumu is aiming to produce a practical and sustainable technology that will be easy to run and operate.

Okumu is keen to explore further cost-saving measures in order cement the mosquito boxes as part of everyday Tanzanian life. Ideas include using the boxes’ solar-panel technology to supply energy to people’s homes and substituting the costly chemical mosquito lure with actual foot odor collected from specially designed cotton pads placed in people’s socks.

“We hope at the end of the two years we will be able to tell the world this is a good strategy to use and start involving industry and more communities and villages,” said Okumu.

The prevalence of malaria in Tanzania has decreased in the last 10 years and Okumu has seen rates in his region dramatically decline from 40% in 1997 to around 7% today.

“We are sure that the reduced rates are due to the improved delivery of bed nets, drugs, insecticides and living standards,” said Okumu. “But malaria is not going to disappear using these existing methods.”

Okumu says he hopes to see his boxes used across the region before existing methods become less effective.

“Mosquitoes can modify their behavior quite rapidly to deal with the added deterrents of sprays and bed nets,” he said.

“For example, instead of going into houses to bite people, mosquitoes are now starting to wait to bite people outside,” he said.

For Okumu, this is a personal as well as a scientific venture. Born in western Kenya, malaria has been apart of Okumu’s life for as long as he can remember.

“All the places I have lived have been malaria zones. When I was growing up I had malaria at least twice every year,” he said.

He continued: “Malaria has claimed so many lives and diseases like this are one of the biggest blocks to our social and economic development.”

CNN

June 28, 2011

Grand Challenges Canada Announces Innovative Rising Stars in Global Health

From a tattoo that delivers drugs to combat the debilitating and disfiguring leishmaniasis disease; to solar powered tablets to train women in Haiti on HIV prevention; to a rugged, reliable fetal heart monitor that doesn’t require electricity in order to save babies’ lives in Africa, Canadian innovators demonstrate creativity, bold ideas and big hearts in the quest to make a difference in the developing world and save lives.

Today Grand Challenges Canada announces 19 grants totalling more than $2 million to Canadian innovators in the first phase of its Canadian Rising Stars in Global Health initiative.

The 19 projects being funded (detailed at www.grandchallenges.ca/canadianrisingstars_round1grantees):

Using mobile phone text messaging to reduce maternal and infant deaths in remote areas in China
Water and power: Energy-efficient water purification developed for point-of-care and scaled for public health
The use of a permanent make-up (or tattoo) device to target drug delivery against cutaneous leishmaniasis
mHealth for maternal and newborn health: Using mobile phones to support community health workers in kenya
Integration of pulse oximetry into the routine assessment of sick young infants at first-level clinics in Karachi, Pakistan
PPAR-gamma agonists for the treatment of cerebral malaria – tweaking the host response to save brains
Saving mothers: Preventing maternal mortality in rural Africa
A primary care toolkit to tackle child labour and promote health equity
Egg-free production of influenza vaccines using viral sensitizer technology : A reliable and affordable solution for developing countries
To develop a synergistic, innovative, implementation strategy for self testing for HIV in South Africa.
A low-cost, multiplexed, point-of-care test for extra-pulmonary tuberculosis
The world’s first free university
Paper as enabling platform for cell-based assays for basic research and medical diagnostics in resource-limited environments
Development of non-invasive diagnostic device for Diabetes
Development and evaluation of a tablet-based, community health worker delivered HIV/STI prevention intervention for women living in internally displaced persons camps in Leogane, Haiti
Revamping an old tool: point-of-care molecular diagnostics in blood capillary tubes
The fetal heart monitor project – human energy to save lives
Kumasi & Accra project to prevent AIDS (KAPPA): A social network-based intervention to prevent HIV among men who have sex with men
New therapeutic drug combinations for tuberculosis treatment.

“When I ran the in the Olympic Torch Relay with my wife Sandra, we felt a sense of pride in Canada as we had never felt before,” says Joseph L. Rotman, Chair of Grand Challenges Canada. “I feel the same sense of pride about these outstanding Canadian Rising Stars in Global Health who demonstrate the leadership Canadians can and do contribute to the international community.”

Says Dr. Peter A. Singer, Chief Executive Officer of Grand Challenges Canada: “These innovators are dedicated to bringing change to the world’s poorest countries. They believe Canada has a leadership role in improving health conditions in the developing world. Collectively they are a source of pride for our country.”

“We are enabling Canadians to make their contribution to global health challenges, in collaboration with colleagues in low- and middle-income countries. Grand Challenges Canada is just beginning to tap that potential,” says Dr. Singer.

In a first for a Canadian grant application process, these innovators each produced a short video to explain their ideas to Canadians. These videos are as creative as the ideas proposed, showing our innovators in a new engaging light. To watch the videos visit http://gcc.eyeptv.net

Through a rigorous peer review process, nineteen innovators’ proposals were selected from across Canada each receiving a grant of $100,000. Their ideas are innovative, plan to address barriers to implementation such as community values and ethics, the health systems required to deliver the discoveries, and cost-effective commercialization of their solutions Challenges Canada calls this Integrated Innovation, an approach which improves the success rate of discoveries. If their ideas are robust, effective, and proven, the innovators will be eligible for an additional scale-up grant of up to $1 million for each proposal.

There will be three rounds of Canadian Rising Stars for a total of $20 million. Of this amount, approximately $14 million will be available for scale-up grants.

Grand Challenges Canada is a new global health organization funded by Canada’s foreign aid budget. Its purpose is to fund research to address some of the most difficult global health issues through Integrated Innovation and save lives. Canada is the first country in the world to adopt a grand challenges approach to foreign aid.

Grand Challenges Canada participates in a consortium with Canada’s International Development Research Centre (IDRC) and the Canadian Institutes of Health Research (CIHR). Mr. David Malone, President of IDRC, joins Dr. Alain Beaudet, President of CIHR in congratulating the new grantees.

“The grant recipients have all displayed enormous creativity and commitment to solving global health challenges,” says Dr. Beaudet. “It is exciting and very rewarding to have the opportunity to encourage them in their work.”

Adds Mr. Malone: “We’re very pleased to see Grand Challenges Canada, Canada’s International Development Research Centre and the Canadian Institutes of Health Research take a ‘whole of Canada’ approach to creating the Canadian Rising Stars in Global Health initiative and supporting Canadians’ contribution to global health.”

Today Grand Challenges Canada is also announcing a Request for Proposals (RFP) for Round 2 of Canadian Rising Stars in Global Health. In Round 2, proposal submissions will require developing world innovators to collaborate with Canadians on their bold ideas.

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Please click on the following link to learn more about the Canadian Rising Stars in Global Health Grantees: www.grandchallenges.ca/canadianrisingstars_round1grantees

About Grand Challenges Canada

Grand Challenges Canada is a unique independent not-for-profit organization dedicated to improving the health and well being of people in developing countries by integrating scientific, technological, business and social innovation. Grand Challenges Canada works with the International Development Research Institute (IDRC) and the Canadian Institutes of Health Research (CIHR )and other global health foundations and organizations to find sustainable long-term solutions to the most pressing health challenges. Grand Challenges Canada is hosted at the McLaughlin-Rotman Centre for Global Health. www.grandchallenges.ca

June 25, 2011

Type 2 Diabetes in Newly Diagnosed ‘Can Be Reversed’

An extreme eight-week diet of 600 calories a day can reverse Type 2 diabetes in people newly diagnosed with the disease, says a Diabetologia study.

Newcastle University researchers found the low-calorie diet reduced fat levels in the pancreas and liver, which helped insulin production return to normal.

Seven out of 11 people studied were free of diabetes three months later, say findings published in the journal.

More research is needed to see whether the reversal is permanent, say experts.

Type 2 diabetes affects 2.5m people in the UK. It develops when not enough insulin is produced in the body or the insulin that is made by the body doesn’t work properly.

When this happens, glucose – a type of sugar – builds up in the blood instead of being broken down into energy or fuel which the body needs.

The 11 participants in the study were all diagnosed with Type 2 diabetes within the previous four years.

They cut their food intake drastically for two months, eating only liquid diet drinks and non-starchy vegetables.

Fat loss

After one week of the diet, researchers found that the pre-breakfast blood sugar levels of all participants had returned to normal.

MRI scans of their pancreases also revealed that the fat levels in the organ had decreased from around 8% – an elevated level – to a more normal 6%.

Three months after the end of the diet, when participants had returned to eating normally and received advice on healthy eating and portion size, most no longer suffered from the condition.

Professor Roy Taylor, director of Newcastle Magnetic Resonance Centre at Newcastle University and lead study author, said he was not suggesting that people should follow the diet.

“This diet was only used to test the hypothesis that if people lose substantial weight they will lose their diabetes.

“Although this study involved people diagnosed with diabetes within the last four years, there is potential for people with longer-standing diabetes to turn things around too.”

Susceptibility question

Dr Ee Lin Lim, also from Newcastle University’s research team, said that although dietary factors were already known to have an impact on Type 2 diabetes, the research showed that the disease did not have to be a life sentence.

“It’s easy to take a pill, but harder to change lifestyle for good. Asking people to shift weight does actually work,” she said.

However, not everyone in the study managed to stay free of diabetes.

“It all depends on how much individuals are susceptible to diabetes. We need to find out why some people are more susceptible than others, then target these obese people. We can’t know the reasons for that in this study,” Dr Lim said.

Professor Edwin Gale, a diabetes expert from the University of Bristol, said the study did not reveal anything new.

“We have known that starvation is a good cure for diabetes. If we introduced rationing tomorrow, then we could get rid of diabetes in this country.

“If you can catch people with diabetes in the early stages while beta cells are still functioning, then you can delay its onset for years, but you will get it sooner or later because it’s in the system.”

But Keith Frayn, professor of human metabolism at the University of Oxford, said the Newcastle study was important.

“People who lose large amounts of weight following surgery to alter their stomach size or the plumbing of their intestines often lose their diabetes and no longer need treatment.

“This study shows that a period of marked weight loss can produce the same reversal of Type 2 diabetes.

“It offers great hope for many people with diabetes, although it must be said that not everyone will find it possible to stick to the extremely low-calorie diet used in this study.”

Dr Iain Frame, director of research at Diabetes UK, which funded the study, said the diet was not an easy fix.

“Such a drastic diet should only be undertaken under medical supervision. Despite being a very small trial, we look forward to future results particularly to see whether the reversal would remain in the long term.”

June 7, 2011

Drug Firms Cut Vaccine Prices to the Developing World

Several major drugs companies have announced big cuts to the amounts they charge for their vaccines in the developing world.

GlaxoSmithKline (GSK), Merck, Johnson & Johnson and Sanofi-Aventis have agreed to cut prices through the international vaccine alliance Gavi.

GSK said it would cut the price of its vaccine for rotavirus by 67% to $2.50 (£1.50) a dose in poor countries.

Rotavirus-related diarrhoea kills more than 500,000 children a year.

The vaccine will be subsidised by higher prices being charged in richer countries.

The rotavirus vaccine, for example, would cost about $50 in the US.

‘Helped out’

“What we need is a return to invest in the next generation of new vaccines and drugs and that has to come from the profits of the medicines or the vaccines,” Andrew Witty, chief executive of GSK told the BBC.

“But it’s obvious that if you’re in Kenya or a slum in Malawi or somewhere like that there is no capacity for those people to contribute to it, so they have to be helped out by the contribution from the middle and the richer (countries).”

Gavi is a partnership representing public and private sector organisations that helps to fund mass vaccination programmes in developing countries.

It is committed to funding the introduction of rotavirus vaccinations in 40% of the poorest countries by 2015, but it faced a $3.7bn funding shortfall and so has been appealing for price cuts and donations.

It will be holding a pledging conference in London on 13 June.

Anti-poverty campaigners welcomed the move but also called on world leaders to act.

“The pricing commitments announced today help drive momentum, but Gavi’s ambition to save four million lives in the next five years is only achievable if the international donor community steps up to the plate on 13 June,” said Jamie Drummond, executive director of campaign group ONE.

Malaria vaccine

Merck has said it will provide its own rotavirus vaccine for $5 a dose, coming down to $3.50 once more than 30 million doses have been sold.

The price Gavi pays for pentavalent vaccines, which protect against diphtheria, tetanus, pertussis, hepatitis B and Haemophilus influenzae type B will be cut by two Indian firms, Serum Institute and Panacea Biotec.

GSK also said it was very close to developing the world’s first malaria vaccine, which is unusual because there is no market for it in the West.

That means there is no opportunity for patients in richer countries to subsidise those in poorer countries.

As a result, GSK said that if the vaccine comes to market it would be sold at a price that provides a small return of 5%, which would be used to fund the next generation of malaria treatments.

Save the Children called on other companies to replicate the “landmark move” which it said could prevent hundreds of thousands of “needless deaths”.

“It’s important that Gavi now uses this to spur other vaccine producers to reduce prices and work to foster greater competition amongst producers to drive prices down even further and help even more children,” said chief executive Justin Forsyth.

June 2, 2011

Poverty Link to Starting Periods Younger

Girls from poorer backgrounds are more likely to start their periods at a younger age, thereby increasing their risk of breast cancer, a UK study says.

It found girls in lower socio-economic groups with typically poorer diets began at 12.1 years on average compared to 12.5 years for wealthier girls.

Their breast cancer risk was greater as they produced the hormone oestrogen longer, the study of 90,000 women says.

It was published in the journal Paediatric and Perinatal Epidemiology.

The research data being gathered from this group of women over 40 years is also helping to find the causes and risk factors associated with breast cancer.

The study is a partnership between Breakthrough Breast Cancer and the Institute of Cancer Research.

This research found that there was little change in the age of menarche (when a girl’s periods begin) for 40 years until the late 1980s.

Then the age dropped from 12.6 years to about 12.3 years, with the drop steepest in poorer areas.

Study author Danielle Morris, from The Institute of Cancer Research in Surrey, said the results suggested that girls, particularly from poorer backgrounds, are starting their periods younger.

“While we don’t know all the reasons behind this, changes in diet may have played a part.

“This decrease is important because the age at which a girl starts her periods can influence her chances of developing breast cancer later in life.”

Oestrogen effect

Dr Tabitha Randall, consultant paediatrician at Nottingham Children’s Hospital, said this was due to exposure to the hormone oestrogen.

“Girls who start their periods earlier are producing oestrogen for longer periods of time, although those who start their periods early normally finish early, but then they may start taking hormone replacement therapy.”

Previous research has shown that the female hormone oestrogen is linked to the growth of breast tumours.

Levels of oestrogen in the body are also influenced by diet and, therefore, body weight.

“Diet is important because fatty tissue turns male hormones into oestrogen,” said Dr Randall.

Previously, girls from higher socio-economic groups tended to start their periods younger because their affluence led to greater food intake and heavier body weight.

But researchers say the trend appears to have reversed.

Girls of lower socio-economic status are now starting their periods at a younger age (12.1 years) than girls from wealthier backgrounds (12.5 years) because they are the ones who tend to have poorer diets and are more likely to be overweight.

The age at which girls start their periods can be added to the list of risk factors for breast cancers, which are known to be a woman’s age, alcohol intake, weight and use of hormone replacement therapy and the contraceptive pill.

A family history of breast cancer may also increase the risk of developing the disease.

Professor Anthony Swerdlow, co-leader of the Breakthrough Generations Study, says that the incidence of breast cancer has risen progressively over a long time in the UK.

“We think these changes have come about through a combination of factors each of which individually makes a small difference.

“Understanding how these factors influence a woman’s risk of developing breast cancer should allow us to develop strategies for preventing the disease in the future.”

June 2, 2011

Newly Identified Chemicals Fool Mosquitoes

Researchers have identified a low-cost chemical that interferes with a mosquito’s ability to detect humans, a study which offers a striking breakthrough in the battle against malaria.

Mosquitoes have carbon dioxide sensors with which they are able to smell the presence of humans in their neighborhood. The newly identified chemicals consist of odor molecules that disrupt these carbon-dioxide sensors located in small, antennae-like appendages close to the mosquito’s mouth, thereby disrupting the mechanism that alert mosquitoes to exhaled human breath. The study is presented in the journal Nature.

It is hoped that the findings could help develop the next generation of mosquito repellents, which could work by confusing the insects.

DEET are the gold standard insect repellants but they are costly and requires repeat applications and therefore beyond the means of many in the developing countries. This discovery could prove invaluable to poor tropical countries by providing an alternative to DEET.

According to the World Health Organization, malaria kills between 800,000 to 1 million people each year, most of who are in Sub-Saharan African. Children and pregnant mothers are the most vulnerable.

June 1, 2011

Mosquitoes are Suckered in New Malaria Research

(AFP) –

PARIS — In the biggest lab breakthrough against malaria in years, scientists on Wednesday said they had identified odour molecules that baffle blood-thirsty mosquitoes.

The molecules disrupt carbon-dioxide sensors that alert mosquitoes to exhaled breath, which signals the presence of a human nearby, the team reported.

The work could lead to revolutionary but low-cost chemicals to confuse, deter or trap mosquitoes, it said.

They could be invaluable in poor tropical countries, providing an alternative to DEET, a skin repellent that is expensive, needs repeat applications and is showing worrying signs of resistance.

“These chemicals offer powerful advantages as potential tools for reducing mosquito-human contact and can lead to the development of new generations of insect repellents and lures,” said Anandasankar Ray, an assistant professor of entomology at the University of California at Riverside, who led the study.

Traps for mosquitoes already exist, in the form of dry ice, gas cylinders of carbon dioxide or propane combustion.

But these gadgets are too bulky and far too expensive to be used for mosquito control, especially in poor settings.

Future mosquito traps, Ray predicted, could be “highly portable, convenient and easily replenishable.”

Malaria claimed 781,000 lives in 2009, according to the UN’s World Health Organisation (WHO), which is heading efforts to distribute insecticide-treated mosquito nets and to spray reproduction sites.

About 90 percent of malaria deaths each year occur in Africa and 92 percent of those are children aged under five.

Other mosquito-borne diseases are dengue, which sickens around 50 million people each year, yellow fever, filariasis and West Nile virus.

Building on research on fruitflies, a common laboratory tool, Ray’s team looked at three of mosquito species whose females are disease vectors: Anopheles gambiae, Aedes aegypti and Culex quinquefasciatus.

The odour molecules that they identified disrupt receptor cells for carbon dioxide located in tiny, antennae-like appendages close to the mosquito’s mouth.

These receptors are activated by a whiff of carbon dioxide, triggering a signal in the brain that prompts the insect to fly upwind, following the puffs of CO2 until they reach its source. Mosquito also use heat sensors and sight to home in on their meal.

The findings have been tested in a small-scale experiment in Kenya, using huts where alluring plumes of CO2 were released to attract mosquitoes and odour molecules were released to bamboozle them.

Mark Stopfer, a specialist at the US National Institutes of Health (NIH), said the results opened up “a promising line of defence.”

He added some words of caution, saying that mosquitoes were attracted to other odours in human sweat and skin. In addition, the chemicals that have been tested on insects so far have not yet been tested for safety on humans, he noted.

June 1, 2011June 1, 2011

Confusing Mosquitoes to Fight Deadly Disease

As summer begins, thoughts often turn to hot dogs, hamburgers, watermelon … and mosquitoes.

For most barbecuers, the bugs are little more than a pesky annoyance. But for millions around the world every year, mosquitoes carrying diseases such as malaria, dengue fever and West Nile virus prove deadly. Mosquito nets and repellants help fight bites, but public health officials still seek cheaper and more effective ways to fight mosquito-borne disease.

Enter researchers at UC Riverside, who reported Wednesday in the journal Nature on three classes of odor molecules that could potentially keep mosquitoes away from people. The chemicals work by blocking the mosquitoes’ ability to detect carbon dioxide — the key cue that leads the insects to their human victims. Mosquitoes zero in on exhaled breath to find you and make you their lunch.

The types of odor molecules work in three ways. The first set inhibits mosquitoes’ and flies’ carbon-dioxide receptors. The second set mimics carbon dioxide. The third set overstimulates carbon-dioxide-sensing neurons, making them unable to detect CO2 for several minutes.

Though the compounds haven’t yet been approved for use in humans, UC Riverside researchers think they might be used to create traps that could replace the bulky and expensive CO2-spewing models in use today.

“Odor molecules that mimic carbon dioxide activity … can lead to the development of small and inexpensive lures to trap mosquitoes — a great benefit, especially to developing countries,” said Anandasankar Ray, an assistant professor of entomology at UC Riverside, in a press release.

The research, which included wind-tunnel experiments and other tests, tested the compounds on three disease-carrying mosquitoes: Anopheles gambiae (which transits malaria), Aedes aegypti (dengue and yellow fever) and Culex quinquefasciatus (West Nile virus and filariasis, also known as elephantiasis). The work was funded by the Bill and Melinda Gates foundation.

UC Riverside has patents on the discovery, which it has licensed to a new startup, Olfactor Labs. The company plans to have product prototypes in 2012.

For more information about products currently available to ward off mosquito bites, check out this piece on natural repellents and this story on DEET drawbacks. Read here for tips on choosing an insect repellant.

Los Angeles Times reporter Amina Khan wrote in April about efforts to engineer genes to fight malaria and in February about a mosquito subspecies that was making work harder for health workers.

By Eryn Brown, Los Angeles Times / for the Booster Shots blog