Wiki Actu en

August 2, 2014

International team of scientists studies malaria drug resistance in Southeast Asia

International team of scientists studies malaria drug resistance in Southeast Asia

From Wikinews, the free news source you can write!
Jump to: navigation, search

Saturday, August 2, 2014

Southeast Asia

Health
Related articles

Health
Collaborate!
  • Pillars of Wikinews writing
  • Writing an article

Researchers from Asia, Africa, Europe, and the United States have mapped resistance of malaria-causing parasite Plasmodium falciparum to antimalarial drug artemisinin, mainly in Southeast Asia; correlated the resistance-causing mutation with slow parasite clearance; and found that prolonged therapy is highly effective against drug-resistant malaria. Their study was published in New England Journal of Medicine on Thursday.

The mutation considered in this study was identified last year as the molecular marker of artemisinin-resistant malaria. The current study found the mutation, located in the propeller domain of a Kelch protein on human chromosome 13, predicted when parasite clearance half-life would exceed five hours with 91.8% sensitivity and 88.4% specificity — usually correct in predicting both when long half-life would occur, and when it wouldn’t. OpenClinica web-based database was used for collection of data which was used to assess parasite clearance rate.

The study found a six-day treatment course effective against artemisinin-resistant malaria. The standard regimen consists of three-day dihydroartemisininpiperaquine treatment, and had a 25% rate of failure at day 42 in another recent study in Pailin, Cambodia. The prolonged regimen which includes three days of artesunate followed by three days of dihydroartemisinin–piperaquine, has shown 2% rate of failure at day 42 in the same area. Geometric mean of the half-life values were similar in two treatment groups of 60 patients each at each study site: one group received artesunate at a daily dose of 2 mg per patient’s body-weight kilogram and the other 4 mg per kilogram. Afterwards, patients at several study sites were followed for 42 days — Pailin, Cambodia; Attapeu, Laos; Binh Phuoc, Vietnam; Shwe Kyin, Myanmar; and Pingilikani, Kenya — and for 28 days in Kinshasa, DR Congo. The treatment regimens were highly effective at all the study sites.

Support for the study came from the UK Department for International Development, the Worldwide Antimalarial Resistance Network, the Intramural Research Program of the National Institute of Allergy and Infectious Diseases of the National Institutes of Health, and the Bill and Melinda Gates Foundation. Also, the UK-based Wellcome Trust funds one of the participating research organizations, the MahidolOxford Tropical Medicine Research Programme.



Sister links

  • Wikipedia-logo-v2.svg Artemisinin-based combination therapies

Sources

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

February 25, 2014

Researchers identify protein responsible for malaria transmission

Researchers identify protein responsible for malaria transmission

From Wikinews, the free news source you can write!
Jump to: navigation, search

Tuesday, February 25, 2014

Health
Related articles

Health
Collaborate!
  • Pillars of Wikinews writing
  • Writing an article

Plasmodium falciparum gametocytes.

Two groups of researchers have independently identified the the protein responsible for malaria transmission to mosquitoes in studies published in journal Nature on Sunday.

The scientists found a direct relationship between the protein AP2-G’s with malaria gametocytes (male and female sexual forms) production, which is necessary for the transmission. Only the sexual forms infect mosquitoes and sexual reproduction occurs within the mosquito digestive tract.

Malaria is caused by Plasmodium parasites. The initially separate teams looked at different plasmodium species. One, an international group led by Manuel Llinás of Penn State University in the US, examined Plasmodium falciparum, which is responsible for the worst form of human malarial infections; the other, led by UK scientists Oliver Billker from the Wellcome Trust Sanger Institute in England and Andy Waters from University of Glasgow in Scotland, looked at Plasmodium berghei, which infects rodents.

The P. falciparum group was kickstarted by research in Spain which found different organisms from the same strain with identical DNA had varying levels of AP2-G, with a strong correlation to their levels of sexual activity. The more AP2-G, the higher the rate of gametocyte formation. Researchers in England, later also drawn into the international team, analyzed the genomes of two mutated strains of P. falciparum which were both unable to form gametocytes. They found that the gene responsible for producing the AP2-G protein was the only common non-functioning gene.

The international team found found the AP2-G protein catalyzes the transmission by activating a relevant gene set in the parasite.

Women tend to their malaria-infected babies in Angola.
Image: USAID Africa.

Both teams confirmed the finding by gene therapy — both by adding the gene into a mutated strain and observing its ability to form gametocytes, and the other way round.

The parasites exist in a mosquito, then in a human, and require subsequent transmission for the parasite to spread. The transmission can only happen through gametocytes. The parasite triggers formation of the sexual gametocytes into the human’s circulatory system every two days in small quantities — not wasting energy on the process at the dry time of year when few mosquitoes are available — but little was known about the mechanism.

Dr. Oliver Billker commented on the potential of getting the transmission of malaria under control, unlike the existing focus on addressing the phrase causing the clinical symptoms, “Current drugs treat patients by killing the sexless form of the parasite in their blood — this is the detrimental stage of the malaria lifecycle that causes illness. However, it is now widely accepted that to eliminate malaria from an entire region, it will be equally important to kill the sexual forms that transmit the disease.”

The researchers hope to continue research toward drugs to prevent the transmission of the disease. The science was funded by groups including UK research councils, the Spanish government, the U.S. National Institutes of Health, and the European Commission.



Sources

External links

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

February 5, 2009

US Supreme Court judge Ginsburg undergoes surgery for pancreatic cancer

US Supreme Court judge Ginsburg undergoes surgery for pancreatic cancer

From Wikinews, the free news source you can write!
Jump to: navigation, search

Thursday, February 5, 2009

Ruth Bader Ginsburg in 2006
Image: Steve Petteway.

Health
Related stories

Health
More information on Health at Wikipedia, the free encyclopedia:
  • Health
  • Health care
  • Medicine
  • Medicine portal

United States Supreme Court Associate Justice Ruth Bader Ginsburg, 75, has undergone surgery for early pancreatic cancer today. The disease was spotted during a routine check-up. She is likely to be hospitalised for ten days.

“Justice Ginsburg had no symptoms prior to the incidental discovery of the lesion during a routine annual checkup in late January at the National Institutes of Health in Bethesda, Maryland,” the Supreme Court announced.

Ginsburg underwent sugery and had chemotherapy for colorectal cancer in 1999; her mother and husband also suffered from cancer.

She was appointed to the Supreme Court by President Bill Clinton in 1993, and is considered to be on the liberal wing of the nine-member court.

A spokesman for President Barack Obama said that Obama’s thoughts and prayers are with Ginsburg.

According to the American Cancer Society, the one-year survival rate for pancreatic cancer is 24%, and the five-year survival rate is 5%.



Sources

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

October 4, 2008

Study estimates first human HIV infection 100 years ago

Study estimates first human HIV infection 100 years ago

From Wikinews, the free news source you can write!
Jump to: navigation, search

Saturday, October 4, 2008

Scanning electron micrograph of HIV-1
Image: CDC.

An eight year study, published in scientific journal Nature, claims the HIV-1 virus that leads to AIDS could have infected humans around 1908 in Africa. Scientists found traces of the HIV-1 genome collected in 1960 from a woman who lived in Léopoldville, presently called Kinshasa, the capital of the Democratic Republic of the Congo. An earlier study had also isolated the virus from a 1959 blood sample of a male from Léopoldville. Study of both the samples and estimate of the rate at which the virus mutates over time has led the researchers to conclude that the human strain could have been around for 100 years.

The study, co-sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), part of the U.S. National Institutes of Health, was carried out by Michael Worobey of the University of Arizona in Tucson, Arizona and colleagues from the United States, France, Belgium, Australia, Democratic Republic of the Congo and Denmark.

Cquote1.svg HIV is one of these pathogens that you could almost think of as living on the edge of extinction. It means there are things we could do to actually make it so that it doesn’t have a chance of spreading. Cquote2.svg

—Michael Worobey, University of Arizona in Tucson

Earlier estimates of this nature had indicated the first infection in humans occurred between 1915 and 1941. The present study pushes the date of the infection back to sometime between 1884 and 1924, with a more focused estimate at 1908. Earlier studies have suggested that HIV-1 virus was spread from chimpanzees to humans in Cameroon.

“Now, for the first time, we have been able to compare two relatively ancient HIV strains. That helped us to calibrate how quickly the virus evolved and make some really robust inferences about when it crossed into humans, how the epidemic grew from that time, and what factors allowed the virus to enter and become a successful human pathogen,” Dr. Worobey said.

“HIV is one of these pathogens that you could almost think of as living on the edge of extinction,” Worobey continued. He believes that had HIV not been carried to a city, it may not have survived the jump to humans.

“It means there are things we could do to actually make it so that it doesn’t have a chance of spreading,” Worobey said.

The first human infection could have happened around the time when the colonial cities were established in Africa. Rapid urbanization in colonial Africa around the beginning of the twentieth century may be responsible for the spread of the AIDS pandemic. It is estimated that several thousand people were infected by the 1960s. Today, HIV infection is reported in 33 million people and has killed 25 million. Researchers opine that an understanding of the origin and pathways for human infection of the virus could help in developing a vaccine to fight it.



Sources

Wikipedia
Wikipedia has more about this subject:
HIV
Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

September 25, 2008

Incomplete data may mislead doctors into overprescribing expensive medicines

Incomplete data may mislead doctors into overprescribing expensive medicines

From Wikinews, the free news source you can write!
Jump to: navigation, search

Thursday, September 25, 2008

Rx symbol.png
Health
Related stories
  • 6 June 2015: Major haemorrhage linked to alcoholism announced as cause of Charles Kennedy’s death
  • 2 June 2015: Beau Biden, son of US vice president, dies at 46
  • 1 June 2015: Kerry hospitalized after cycling accident
  • 8 May 2015: Teen accused of Anzac Day terror plot applies for bail
  • 8 May 2015: Indiana Governor signs needle exchange program

Health
More information on Health at Wikipedia, the free encyclopedia:
  • Health
  • Health care
  • Health science
  • Medicine
  • Public health

Medical doctors have not been getting the full picture about newly FDA-approved drugs, concludes a research team from the University of California, San Francisco. This is because not all the studies required for FDA approval get published. New drug studies that do see publication tend to be ones where the medicine appears to perform well while poor and middling results are less likely to appear in medical journals. The result appears to be that doctors who read the available literature may get an inflated impression of new medications and may prescribe expensive new drugs in place of older medicines that perform as well or better. As Jordan Lite of Scientific American wonders, are drug companies cherry-picking the studies they publish to make their drugs look better than they actually are?

The University of California team reviewed trials that had supported new drugs approved from 1998 to 2000 and examined 909 trials of 90 medications. The search was conducted upon PubMed and other search tools that a typical medical doctor or patient could access. They concluded that less than half of the studies had been published five years after drug approval and a publication bias existed.

Erick Turner, who coauthored a similar study earlier this year, expressed concerns to Scientific American that the problem was not merely the raw percentage of studies published, but that a disproportionate share of the research that appeared in journals are examples where new medications appear to perform well:

Cquote1.svg When trials are selectively published … it will skew the efficacy of the drug and make it look like it works better than it does. Cquote2.svg

—Erick Turner

When trials are selectively published … it will skew the efficacy of the drug and make it look like it works better than it does. It’s going to create a lot more enthusiasm among consumers of that information or in the words of Alan Greenspan, ‘irrational exuberance.’

Ken Johnson, senior vice president of the Pharmaceutical Research and Manufacturers of America (PhRMA), defended the pharmaceutical industry by saying FDA review of new drug applications is more important than publishing the results of medication trials in medical journals. Approved medications come with labels that give patients and doctors enough information, assures Mr. Johnson.

Yet concerns about full and appropriate disclosure have been serious enough that a new law was enacted last year. FDA Amendments Act of 2007 (FDAAA) requires that all trials which support FDA-approved drugs be registered at the National Institutes of Health website. The requirement goes into effect this coming Saturday. Congress enacted the legislation in response to hearings that determined pharmaceutical companies were less likely to publish studies that indicated significant side effects. One shortcoming in the legislation, according to UCSF associate professor Ida Sim, is that the FDA is still not required to specify which trials it weighs when considering applications for drug approvals. Yet she praises the new law as a major improvement. It’s critically important that we know trials exist and that we get the summary results, positive and negative, into the public domain—that’s a huge step and more than any [other] country is doing now.



Sources

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

August 5, 2008

Vitamin C can help prevent cancer say the National Institutes of Health

Vitamin C can help prevent cancer say the National Institutes of Health

From Wikinews, the free news source you can write!
Jump to: navigation, search

Tuesday, August 5, 2008

Vitamin C molecule

Linus Pauling in 1954

Vitamin C can help cut the spread of cancer and tumours by half, according to United States researchers who tested on mice.

Researchers at the National Institutes of Health injected doses of vitamin C into four grams per kilo of body weight into mice with pancreatic, brain and ovarian cancers, which started a destructive chain reaction with the cancer cells. The vitamin, also known as ascorbate, caused high amounts of hydrogen peroxide in the body, which killed cancer cells.

The vitamin was given in doses as the body does not absorb more than a set amount of vitamin C normally. Following successful tests on mice, scientists believe that treating cancer with vitamin C could soon be tested on humans.

Treating cancer with vitamin C was considered in the 1970s by American scientist Linus Pauling, who won the Nobel Prize in Chemistry in 1954. However, it involved taking the vitamin orally instead of injection, and so did not have the desired effect.



Sources

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

September 21, 2007

Experimental AIDS vaccine fails

Experimental AIDS vaccine fails – Wikinews, the free news source

Experimental AIDS vaccine fails

From Wikinews, the free news source you can write!
Jump to: navigation, search

Friday, September 21, 2007

Stylized rendering of a cross-section of the AIDS virus.
Image: United States Department of Energy.

An experimental AIDS prevention vaccine has failed in the latest crucial experiment as more inoculated volunteers contracted HIV than volunteers who were not inoculated.

Merck & Company said that it is withdrawing its involvement in the international study, which is funded by the National Institutes of Health.

The Associated Press reports that officials from the New Jersey-based company said that 24 of 741 volunteers who got the vaccine contracted HIV. In the control group which received a placebo injection, 21 subjects were seropositive.

Keith Gottesdiener, the head of Merck & Company’s infectious disease and vaccine research group, said, “It’s very disappointing news… A major effort to develop a vaccine for HIV really did not deliver on the promise.” Merck had been working on the vaccine for the past decade.

Merck said that all the volunteers who participated in the study did not have HIV when the program began, but were at a high risk of contracting the disease. The majority of the volunteers were either homosexual males or female sex workers.

Another goal of the vaccine was to lessen the severity of the disease for people that did contract it. Officials say that goal was also not met.

The AIDS Vaccine Advocacy Coalition says that while Merck’s unsuccessful test is a disappointment, they will continue researching possible vaccines.

Because the body’s immune response to the virus causing AIDS is ineffective, many physicians have serious doubts that an HIV vaccine will ever be possible. Research into the matter is needed nonetheless because a vaccine has an enormous potential in fighting the global AIDS pandemic.



Sources

Wikipedia
Wikipedia has more about this subject:
AIDS
Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

February 22, 2007

Large study provides new insights in autism\’s genetic code

Large study provides new insights in autism’s genetic code

From Wikinews, the free news source you can write!
Jump to: navigation, search

Thursday, February 22, 2007

Ideogram of the human chromosome 11

In the largest study of its kind, a genetic analysis of 1,168 families with multiple cases of autism has identified genetic links to autism. A previously overlooked stretch of DNA on chromosome 11 implicates a gene called neurexin 1 and increases the evidence for the involvement of neurexins and genes related to glutamate transmission in the brain.

Genetic studies of autism have previously been undertaken; however the new study involves the collaboration of more than 120 scientists from more than 50 institutions representing 19 countries who pooled their data as part of the Autism Genome Project. The findings were published in the Feb. 18 issue of Nature Genetics.

Bob Wright, co-founder of Autism Speaks, a non-profit organization dedicated to increasing awareness of autism, said: “The identification of susceptibility genes will provide profound new insight into the basis of autism offering a route to breakthroughs in new treatments in support of families.” Autism Speaks funded this project in conjunction with the U.S. National Institutes of Health.

Joachim Hallmayer, MD, associate professor of psychiatry at Stanford and chair of the collaboration’s executive committee, explains what is next: “While promising, these results need to be followed up with more refined genetic maps to home in on other specific candidate genes. We also need to look more closely at chromosomal anomalies in large samples of children with autism.” In the paper, researchers caution that the genetic foundation of autism probably involves multiple genes and chromosomal abnormalities.

Autism affects about one in every 150 children, and the CDC has called it an “urgent health concern”. Autism is a developmental disorder which impairs social interaction, communication and features restricted and repetitive interests and activities. Twin studies and other research clearly suggest a genetic basis for the condition. Currently there is no cure for autism, but both behavioral or sensory interventions and drugs can influence the symptoms.

Sources

Bookmark-new.svg


This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

February 15, 2007

A weak spot in HIV spotted

A weak spot in HIV spotted – Wikinews, the free news source

A weak spot in HIV spotted

From Wikinews, the free news source you can write!
Jump to: navigation, search

Thursday, February 15, 2007

Scientists have discovered a place on the outside part of AIDS virus that might be vulnerable to antibodies blocking the virus from infecting human cells. This could mean that an anti-HIV vaccine is possible in the future.

According to Peter Kwong, researcher at U.S National Institute of Health (NIH), this study is likely to contribute to finding HIV’s “site of vulnerability” which could then be targeted with a vaccine that prevents the initial infection.

Schematic diagram of the human immunodeficiency virus (HIV).

The team of researchers have made atomic-level images of HIV and revealed the structure of a protein on the surface of the virus. This protein, called gp120, binds to an infection-fighting antibody and seems to be susceptible to attacks by this antibody called ‘b12’. B12 can broadly neutralize the virus.

Researchers detailed the precise interaction as the virus tries to hook on to and infect cells sent to protect the body. They have captured an image of how the virus of human immunodeficiency attacks the human cells. Dr. Gary Nabel, an NIH vaccine expert and a co-author of the research, describes this first contact between the virus and the cells as a ‘cautious handshake’ which then becomes a ‘hearty bear hug’. The virus grabs and infects the cells that are aimed at protecting the body.

Then the virus mutates quickly to fight the immune system’s attacks as well as to counter the effect of antibodies that block the proteins with help of which HIV binds to a cell to infect it.

Scientists agree that a vaccine against AIDS would be an ideal way to stop the pandemic of this disease, but, with all importance of these findings, much work and studies are still needed. This implies that any vaccine against AIDS is probably still many years away.

The AIDS virus has killed more than 25 million people since it was first detected in 1981. Sub-Saharan Africa is the most severely affected by the epidemic. Approximately 40 million people live with HIV.

About a dozen potential vaccines are currently under development. Two products, one by Merck and one by Sanofi-Aventis, are now in advanced human trials.

Sources



Bookmark-new.svg

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.

July 19, 2006

Stem cell bills passed by US House and Senate

Stem cell bills passed by US House and Senate

From Wikinews, the free news source you can write!
Jump to: navigation, search

Wednesday, July 19, 2006

The Stem Cell Research Enhancement Act of 2005 (HR810), approved by the US House of Representatives in 2005, gained a 63-37 approval in the Senate on July 17th, 2006, and will now be presented for presidential approval or veto.

Bill HR810 passed by the Senate as SB471, overrides the 2001 executive order signed by George W. Bush that banned funding by the National Institutes of Health (NIH) for embryonic stem cell research of stem cell lines created after the executive order was issued. The new bill does not include a provision against privately funded research, which is legal under the law, only research funded by NIH.

The bill includes three ethical requirements for funded research. First, the stem cells were derived from human embryos that have been donated from in-vitro fertilization clinics, were created for the purposes of fertility treatment, and were in excess of the clinical need of the individuals seeking such treatment. Second, prior to the consideration of embryo donation and through consultation with the individuals seeking fertility treatment, it was determined that the embryos would never be implanted in a woman and would otherwise be discarded. And lastly, the individuals seeking fertility treatment donated the embryos with written informed consent and without receiving any financial or other inducements to make the donation.

President Bush is expected to veto the bill as early as today, White House Press Secretary Tony Snow said the veto would be “pretty swift”. This would be President Bush’s first veto of his two terms in office.

As with any vetoed bill, a two-thirds majority of the House and Senate can override said veto, but the original vote (63-37) show that the Senate is more than likely to not get the override votes it would need. Even without the two-thirds original vote, Senator Carl Levin of Michigan has voiced support for a veto override.

Two other bills, S2754 and S3504, the Alternative Pluripotent Stem Cell Therapies Enhancement Act and the Fetus Farming Prohibition Act of 2006, respectively, were failed and passed in that order by the House of Representatives. S2754 was introduced to the House this afternoon and failed by a vote of 273-154, S3504 was passed unanimously by the House and is also expected to be on the President’s desk this morning.

Related

Sources



Bookmark-new.svg

This text comes from Wikinews. Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution 2.5 licence. For a complete list of contributors for this article, visit the corresponding history entry on Wikinews.
Older Posts »

Powered by WordPress