Healthy Me - At Home and Away: Imperial College London

Showing posts with label Imperial College London. Show all posts

Friday, May 6, 2011

Gene-modified mosquitoes offer malaria hope

Image via WikipediaBy James GallagherHealth and Science reporter, BBC News

Scientists believe they are closer to being able to change the DNA of wild mosquitoes in order to combat malaria.

In the laboratory, they made a gene spread from a handful of mosquitoes to most of the population in just a few generations, according to a report in Nature.

If the right gene can be made to spread then researchers hope to reduce the number of cases of malaria.

Other academics have described the study as a "major step forward".

The World Health Organisation estimated that malaria caused nearly one million deaths in 2008.

Spreading resistance

Research groups have already created "malaria-resistant mosquitoes" using techniques such as introducing genes to disrupt the malaria parasite's development.

The research, however, has a great challenge - getting those genes to spread from the genetically-modified mosquitoes to the vast number of wild insects across the globe.

Unless the gene gives the mosquito an advantage, the gene will likely disappear.

Scientists at Imperial College London and the University of Washington, in Seattle, believe they have found a solution.

They inserted a gene into the mosquito DNA which is very good at looking after its own interests - a homing endonuclease called I-SceI.

The gene makes an enzyme which cuts the DNA in two. The cell's repair machinery then uses the gene as a template when repairing the cut.

As a result the homing endonuclease gene is copied.

It does this in such a way that all the sperm produced by a male mosquito carry the gene.

So all its offspring have the gene. The process is then repeated so the offspring's offspring have the gene and so on.

In the laboratory experiments, the gene was spread to half the caged mosquitoes in 12 generations.

Defeating malaria

Professor Andrea Crisanti, from the department of life sciences at Imperial College London, said: "This is an exciting technological development, one which I hope will pave the way for solutions to many global health problems.

"At the beginning I was really quite sceptical and thought it probably would not work, but the results are so encouraging that I'm starting to change my mind."

He said the idea had been proved in principle and was now working on getting other genes to spread in the same way.

He believes it could be possible to introduce genes which will make the mosquito target animals rather than humans, stop the parasite from multiplying in the insect or produce all male offspring which do not transmit malaria.

Professor Janet Hemingway, from the Liverpool School of Tropical Medicine, said the work was an "exciting breakthrough".

She cautioned that the technique was still some way off being used against wild mosquitoes and there were social issues around the acceptability of using GM technology.

"This is however a major step forward providing technology that may be used in a cost effective format to drive beneficial genes through mosquito populations from relatively small releases," she added.

Dr Yeya Touré, from the World Health Organisation, said: "This research finding is very important for driving a foreign gene in a mosquito population. However, given that it has been demonstrated in a laboratory cage model, there is the need to conduct further studies before it could be used as a genetic control strategy.

Taken from bbc.co.uk; source article is below:
GM mosquitoes offer malaria hope

Thursday, March 10, 2011

Sugary drinks and your blood pressure

Image by tauntingpanda via FlickrI found another article on the bad effects of sugary drinks to our health. The first few paragraphs are presented here. Follow the link below to read the full artcile.

Read on...
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(Health.com) -- Drinking a lot of soda and other sugary beverages has been linked to an increased risk of obesity and diabetes, among other health problems

Here's another reason to cut back: A new study suggests that even one sweetened drink per day may contribute to higher blood pressure.

The more sugary beverages a person drinks, the higher his or her blood pressure is likely to be, according to the study, which appears in the American Heart Association journal Hypertension.

Each additional soda, lemonade, or fruit drink the study participants consumed on a daily basis was associated with a small but measurable uptick in systolic and diastolic blood pressure of 1.6 and 0.8 points, respectively. (A blood-pressure reading consists of the systolic pressure "over" the diastolic pressure.)

A blood-pressure increase of that magnitude is not a major cause for concern, so the findings may need to be taken with a grain of salt -- or not, since excess sodium is still the prime offender when it comes to high blood pressure (hypertension).

Taken from the CNN source article as follows: click here to continue.

Wednesday, August 18, 2010

New heart valve works best

I would tend to agree that, something new is always better - even for replacements.

Am I making sense here? How can a replacement be new?

Anyway, read on...
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New heart valve taken from patient works best

PARIS : Replacing the heart's aortic valve with one's own pulmonary valve rather than the same body part from a donor boosts survival and quality of life, according to a study released Tuesday.

Oxygen-rich blood in pumped via the aortic valve to nourish the body, while the pulmonary valve is the gateway for oxygen-depleted blood passing into the lungs.

Defects and disease can create the need for the aortic valve to be replaced, a delicate but standard procedure for more than three decades.

The new valve may be mechanical - which is sturdy but requires life-long medication to prevent blood clots - or a graft, taken either from a cadaver or the living heart's other exit valve, which is subject to less stress.

Earlier studies have not shown one method to be clearly superior to the others.

To compare the non-mechanical options for fixing aortic valves, researchers led by Sir Magdi Yacoub of Imperial College London fitted 108 patients with pulmonary valves removed from their own bodies, and another 108 with aortic valves taken from recently deceased donors.

All surgeries were open-heart.

After ten years, four patients had died in the so-called "autograft" or living valve group, as compared to 15 deaths in the "homograft" group that had been given a donor valve.

The survival rate, in other words, was 97 per cent in the first cohort and 83 per cent in the second.

"Our results support the hypothesis that a living valve implanted in the aortic position can lead to significantly improved clinical outcomes," the
researchers said.

"The quality-of-life scores were also significantly better after the Ross operation," they added, referring to the name of the autograft procedure.

In the Ross technique, the removed pulmonary valve is replaced with the same part from a dead donor.

Yacoub conjectured that for the aortic valve, having one's own tissue somehow helped the body cope with the constant changes in pressure and size.

- AFP/il

From ChannelNewsAsia.com; source article is below:New heart valve taken from patient works best
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Sunday, May 3, 2009

Spain leads Europe in swine flu cases with 40

English: Main symptoms of swine flu. (See Wikipedia:Swine influenza#Swine flu in Humans). Model: Mikael Häggström. To discuss image, please see Template talk:Häggström diagrams References Centers for Disease Control and Prevention > Key Facts about Swine Influenza (Swine Flu) Retrieved on April 27, 2009 Joint pain added from general influenza: Centers for Disease Control and Prevention > Influenza Symptoms Page last updated November 16, 2007. Retrieved April 28, 2009 (Photo credit: Wikipedia)

By MARGIE MASON,AP Medical Writer AP - Monday, May 4

MEXICO CITY - Swine flu extended its reach through Europe and Latin America, with at least five countries reporting new cases on Sunday. Health experts were investigating a case of the virus jumping from a person to pigs, trying to determine if the disease was reaching a new stage.

Hong Kong kept 350 people under quarantine in a hotel as a precaution even though no new swine flu infections appeared in Asia, and Egypt's attempt to kill all pigs as a precaution against the disease prompted pig owners to clash with police who were helping to seize their animals for slaughter.

So far the swine flu epidemic has killed 19 in people in Mexico and one toddler in the U.S. and has spread to 18 countries worldwide _ but experts believe the actual spread is much wider.

Mexico's health secretary said 11 people were suspected to have died from the virus in the previous 24 hours. The alarming news came after the epidemic's toll in Mexico appeared to have been leveling off.

The global caseload was nearing 800 and growing _ the vast majority in Mexico, the U.S. and Canada. Colombia on Sunday reported South America's first confirmed case of swine flu a day after Costa Rica reported the first in Central America.

The Spanish Health Ministry said the country now has 40 confirmed cases of swine flu _ making it the European nation hardest hit by the virus. It said most of the victims have already recovered. All but two had recently visited Mexico.

Britain, Italy and Germany also reported new cases.

But just over a week into the outbreak, the virus largely remains an unpredictable mystery.

Hong Kong _ which was criticized for delaying quarantine measures during the SARS outbreak _ sealed the downtown Metropark Hotel, where a sickened Mexican tourist had stayed, trapping 350 guests and employees inside.

About a half dozen police officers wearing masks guarded the hotel Sunday, even though all those at the hotel were reported to be healthy. One guest said he walked on the stairs for exercise and to alleviate boredom.

"It's highly inconvenient. That's what's affecting people, because it took us by surprise," said 45-year-old Kevin Ireland, who was on a business trip from New Delhi, India.

Scientists warn that the virus could mutate into a deadlier form.

"Influenza is unpredictable," said Dr. Tim Uyeki, an epidemiologist at the U.S. Centers for Disease Control and Prevention who has worked on SARS and H5N1 bird flu outbreaks. "There are so many unanswered questions. This is a brand new virus. There's so much we don't know about the human infectious with this virus."

Right now, one of the biggest hurdles is a lack of information from Mexico. A team of international and Mexican virus sleuths is trying to piece together an epidemiological picture of who's dying and where transmission began, while also uncovering just how it's attacking people with severe illness. But details are emerging slowly.

Late Saturday, Mexico's confirmed swine flu cases jumped by about 25 to 473, including the 19 deaths. A Mexican toddler also died in Texas days ago, for a worldwide total of 20.

President Barack Obama urged caution.

"This is a new strain of the flu virus, and because we haven't developed an immunity to it, it has more potential to cause us harm," Obama said. Later, he spoke with Mexican President Felipe Calderon to share information.

Pablo Kuri, a Mexican epidemiologist, said three of the dead were children: a 9-year-old girl, a 12-year-old girl and a 13-year-old boy. Four were older than 60. The other nine were between 21 and 39 _ unusual ages for people to die from flu because they tend to have stronger immune systems.

Although most of the dead were from the Mexico City area, they came from different neighborhoods in the metropolis of 20 million, and there were no similarities linking their medical backgrounds.

One theory for the deaths is that perhaps they sought treatment too late _ falling sick an average of seven days before seeing a doctor. Many of the sick around the world were people who had visited Mexico, including 13 of Britain's 16 cases.

The World Health Organization earlier announced that a pandemic was imminent, but it has decided against declaring a full pandemic alert. Still, that doesn't mean people can relax, said Dr. Mike Ryan, WHO's global alert and response director.

"These viruses mutate, these viruses change, these viruses can further reassort with other genetic material, with other viruses," he said. "So it would be imprudent at this point to take too much reassurance" from the small number of deaths.

In the Canadian province of Alberta, health and agriculture officials said about 220 pigs on a farm were quarantined after being infected by a worker who had recently returned from Mexico. They stressed that swine viruses are common in pigs, and there was no need for consumers to stop eating pork as long as it's handled properly and cooked thoroughly.

The pigs are all recovering in the first documented case of the H1N1 human flu being passed to another species.

In Egypt, police fired shots in the air and tear gas at pig owners who stoned them in an attempt to prevent government workers from slaughtering their animals as a precaution against swine flu. A security official, who spoke on condition of anonymity because he was not authorized to talk to the media, said 12 people were injured in the Manshiyet Nasr slum.

In Baghdad, Iraqi officials killed three wild boars at Baghdad's zoo because of swine flu fears, even though health experts say the virus is not transmitted by pigs. Iraq has no documented cases of swine flu.

Associated Press writers Juan Carlos Llorca and David Koop in Mexico City contributed to this report.

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From Yahoo! News; source article is here.