Cells made to mimic embryonic stem cells
Wed, 06 Jun 2007 17:02:36 GMTBy MALCOLM RITTER, AP Science Writer
NEW YORK - In a big step toward a long-sought goal, three teams of scientists say they've produced the equivalent of embryonic stem cells, at least in mice, without taking the controversial step of destroying embryos.
Their procedure makes ordinary skin cells behave like stem cells. If the same can be done with human cells — a big if — the procedure could lead to breakthrough medical treatments without the contentious ethical and political debates surrounding the use of embryos.
Embryonic stem cells can give rise to all types of tissue, so experts believe they might be used to create transplant therapies for people who are paralyzed or have ilnesses ranging from diabetes to Parkinson's disease.
To harvest human embryonic stem cells, human embryos have to be destroyed, an action opposed by many people. The new studies are the latest to attempt to avoid embryo destruction.
Scientists have long hoped to find a way to reprogram ordinary body cells to act like stem cells, avoiding the use of embryos altogether. The new mouse studies seem to have accomplished that.
"I think it's one of the most exciting things that has come out about embryonic stem cells, period," said stem cell researcher Dr. Asa Abeliovich of Columbia University in New York, who didn't participate in the work. "It's very convincing that it's real."
But he and others cautioned that it will take further study to see whether this scientific advance can be harnessed for new human therapies.
"We have a long way to go," said John Gearhart of Johns Hopkins University, a stem cell researcher who also wasn't involved in the new work.
In any case, it is crucial that scientists continue research with standard embryonic stem cells, said researcher Konrad Hochedlinger of the Harvard Stem Cell Institute, who led one of the three teams.
He and his colleagues present their work in the inaugural issue of the journal Cell Stem Cell. .
The other two teams reported their results Wednesday on the web site of the journal Nature. Rudolf Jaenisch of the Whitehead Institute in Cambridge, Mass., is the senior author of one paper, and the work behind the other paper was led by Shinya Yamanaka of Kyoto University in Japan.
The new work builds on a landmark paper Yamanaka published last August. He found that by slipping four genes into mouse skin cells called fibroblasts, he could make the altered cells behave much like embryonic stem cells in lab tests.
But these so-called "iPS" cells still showed significant differences from embryonic stem cells. The three new papers report on creating iPS cells that proved virtually identical to stem cells in a variety of lab tests.
The four inserted genes regulate the activity of other genes, which is why they can dramatically affect the cell's behavior.
Scientists caution that the experimental procedure followed in the studies wouldn't be suitable for use in treating disease, and that it's not yet clear whether a modified version would work with human cells.
One of the inserted genes is known to promote cancer, and Yamanaka reports that mice carrying descendants of iPS cells showed tumors as a result. He and other researchers said a new approach will be needed that avoids a cancer hazard.
Gearhart called that a major issue to be resolved. In addition, he said, scientists still must show that these cells can give rise to many cell types in the lab, as embryonic stem cells can.
And all this must be accomplished in human cells — a difficult task, he said, because introducing genes into human cells is a major challenge.
If the technique can be harnessed for people, the iPS cells and the tissue they develop into would provide a genetic match to the person who donated the skin cells. That would make them suitable for transplant to that person, theoretically without fear of rejection.
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On the Net:
Nature: http://www.nature.com/nature
Cell Stem Cell: http://www.cellstemcell.com
Video interview of Rudolf Jaenisch:
http://streaming.wi.mit.edu/?subnature_paper&vidnature1.mov
http://streaming.wi.mit.edu/?subnature_paper&vidnature2.mov
http://streaming.wi.mit.edu/?subnature_paper&vidnature3.mov
Medical expert to testify against Glaxo
Wed, 06 Jun 2007 14:12:50 GMTBy MATTHEW PERRONE, AP Business Writer
WASHINGTON - The controversy surrounding GlaxoSmithKline's diabetes drug Avandia mounted Wednesday as a medical expert prepared to tell lawmakers the British drug maker threatened him with legal action when he first raised questions about the treatment's safety.
Dr. John Buse was contacted by Glaxo in 1999 after drawing attention to a trend in heart problems among patients using Avandia, according to testimony he was prepared to give a House committee. Buse says Glaxo representatives mentioned that some in the company wanted to hold him accountable for hurting sales of the drug.
Buse, soon to become president of the American Diabetes Association, said he eventually signed a clarifying statement with the company that was used to ease concerns from investors.
Glaxo's head of research, Moncef Slaoui, and the head of the Food and Drug Administration will also testify before the House Committee on Oversight and Government Reform.
Rep. Henry Waxman, D-Calif., a frequent critic of FDA and the chair of the oversight committee, announced the hearing after an analysis in the New England Journal of Medicine concluded Avandia could raise patients' risk of heart attack by more than 40 percent.
Surgery begins on conjoined twin girls
Wed, 06 Jun 2007 15:53:39 GMTBy M.R. KROPKO, Associated Press Writer
CLEVELAND - Doctors began the first in a series of high-risk surgeries Wednesday to separate 3-year-old twin girls joined at the head.
Doctors hope to separate Tatiana and Anastasia Dogaru, who were born in Italy but are of Romanian descent, through several surgeries in about six months. Without separation, the twins risk dying in early childhood.
There was no indication how long the surgery would take and a report on the twins' condition wasn't planned until Thursday, said Janice Guhl, spokeswoman for University Hospitals' Rainbow Babies & Children's Hospital.
In the daylong procedure Wednesday, surgeons said they would begin at the girls' scalps and slowly make a wedge where the twins' skulls are joined. They plan to remove a rectangular bone flap and reinsert it at the end of the surgery.
The procedure will give neurosurgeons their first real glimpse of the girls' brains. The medical team practiced the procedure on a model designed from images.
How much separation is accomplished Wednesday depends on the complexity of blood vessels, tissue and bone connections.
The girls' parents, the Rev. Alin Dogaru, a Byzantine Catholic priest, and Claudia Dogaru, both 31, have said they view the separation surgeries as the girls' best hope. They arrived in Cleveland on April 6 after 2 1/2 years in Dallas.
Twins born joined at the head — known as craniopagus twins — are rare, occurring in about one in 2.5 million births. The top of Tatiana's head is attached to the back of Anastasia's, and they have never been able to look directly at each other.
Last month, doctors succeeded in establishing independent blood flow in the twins by inserting small coils into veins in their brains. That was viewed as a prerequisite for separation surgery.
Bleeding in these procedures is a major risk. Other potential complications include infection, stroke and a build up of fluid in the brain, doctors say.
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On the Net:
Rainbow-Twins site: http://www.uhhospitals.org/tabid/2390/Default.aspx
Patient has low chance of spreading TB
Wed, 06 Jun 2007 03:39:48 GMTBy COLLEEN SLEVIN, Associated Press Writer
DENVER - The Atlanta lawyer quarantined with a dangerous strain of tuberculosis has a relatively low chance of spreading the disease, possibly allowing him to leave his isolation room for a short time as soon as next week, one of his doctors said Tuesday.
A third test of Andrew Speaker's sputum — a mixture of saliva and phlegm — turned up negative for the presence of TB bacteria, confirming the results of earlier tests at National Jewish Medical and Research Center.
Normally, TB patients with three negative sputum tests who have undergone at least two weeks of treatment are allowed to leave their isolation rooms briefly as long as they wear a mask. Additional precautions are advised for patients, like Speaker, with drug resistant strains of the disease.
If his drug regimen is established and if he wears a face mask, Speaker could be allowed outside on hospital grounds with an escort as early as next week, said Dr. Charles Daley at a news conference.
"I think it's important for people's treatment ... to get outside," Daley said.
However, given the attention Speaker's case has attracted, Daley said it's possible hospital officials or Speaker himself could decide against outside walks to protect his privacy.
Doctors could decide as early as this week whether Speaker should undergo surgery to remove infected tissue, Daley said. On Tuesday, a catheter was implanted in his chest to make it easier for staff to administer antibiotics through IVs, hospital spokesman William Allstetter said.
Doctors are hopeful Speaker's tuberculosis can be cured because it is not widespread, he is otherwise healthy and young, and National Jewish has extensive experience treating drug-resistant infections with a combination of drugs and surgery.
Speaker, 31, originally was found to have multidrug-resistant TB, which can withstand two mainline drugs used to treat tuberculosis. While he was in Europe on his honeymoon last month, tests revealed he had extensive drug-resistant tuberculosis, or XDR-TB, which can withstand more drugs.
Both houses of Congress have scheduled hearings for Wednesday morning to assess how the Centers for Disease Control and Prevention and other federal agencies handled the situation.
After Speaker learned of the more serious diagnosis, he took commercial flights to Canada and drove into the United States. He says that before he left the United States, officials did not order him that he should not to fly.
A border officer at the Champlain, N.Y., crossing has been reassigned and is under investigation for ignoring a computer alert about Speaker, which contained instructions to detain him, don protective gear and call public health authorities.
Under new rules being adopted, individual Customs officers will no longer be able to override instructions to detain someone like Speaker. They would have to get approval from a supervisor, according to a Department of Homeland Security official who spoke on condition of anonymity because no formal announcement had been made.
Doctors in Denver continue to perform tests on Speaker. A smear test is one way to test for the presence of TB bacteria and requires patients to inhale an irritating salt water solution, producing a deep cough. Their sputum is then smeared on a slide and placed under a microscope.
A negative result means there were no germs visible. But a culture test of Speaker's sputum — considered the "gold standard" in TB testing — has yielded TB bacteria.
Allstetter cautioned that a patient with a negative smear test could still have TB bacteria in his sputum, and cited a recent study suggesting that 20 percent of new TB cases could be traced back to contact with smear-negative patients.
Tuberculosis is transmitted by air in nearly all cases. Active TB patients normally cough, dispersing particles that can float in the air for hours. Speaker does not have a cough, Allstetter said.
Health authorities are still trying to contact passengers and crew members who were aboard two trans-Atlantic flights with Speaker last month to advise them to undergo TB testing.
Montana health officials said Tuesday that they were testing and monitoring someone who may have been exposed on a flight, but that they could not identify the person because of confidentiality laws.
Speaker's strain has so far resisted at least 10 of 14 drugs available for treating TB, according to Dr. Michael Iseman of National Jewish. Surgery to remove infected lung tissue, about the size of a tennis ball, is one option. The infection's relatively small size increases the chances of success of surgery.
On Tuesday, Dr. Mario Raviglione of the World Health Organization said there were only two drugs that are effective against Speaker's strain.
Daley declined to comment on Raviglione's remark but said National Jewish could use five or six drugs on Speaker that aren't normally used to treat TB, a common practice with previous drug resistant patients.
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Associated Press writer Devlin Barrett in Washington contributed to this report.
Chinese scientists prove tea can help fight obesity
Wed, 06 Jun 2007 14:39:46 GMTBEIJING - Chinese scientists have proved it -- tea can help make you thin.
Researchers spent five years studying obesity, with the focus on children, the China Daily said.
&;They found that the polyphenol compound in tea -- especially Oolong tea -- can help obese people battle the bulge,&; the newspaper said. &;Scientists have proved that drinking tea can help people lose weight.&;
Guo Xirong, director of the Nanjing Institute for Paediatrics, particularly recommends Oolong tea, the newspaper said.
Chinese have long believed in the link between tea and weight loss, something an Oolong tea Internet home page espouses.
&;It has been confirmed that the continuous intake of Oolong tea contributes to enhancing the function of fat metabolism and to controlling obesity,&; it says of a tea produced and consumed primarily in the southeast of the country.
India passes out condoms at porn movie halls
Wed, 06 Jun 2007 11:46:24 GMTAHMEDABAD, India - Health officials in western India are distributing condoms outside cinema halls screening illegal pornographic films, to promote safe sex and curb the spread of sexually transmitted diseases like HIV/ AIDS.
Officials in Gujarat state said many of those watching the blue movies were from high risk groups such as migrant laborers or truck drivers, who spend a lot of time away from their homes and are therefore more vulnerable to casual and unsafe sex.
&;The migrant population will not stop watching pornographic movies or visiting sex workers,&; said H.K. Anant, a health official in Ahmedabad, Gujarat's main city.
&;All we want them to do is to stop unsafe sex.&;
India has the world's highest number of HIV-positive cases with an estimated 5.7 million people infected, according to the United Nations.
In Gujarat's 800 small cinema halls, young male volunteers stand outside handing packets of condoms to audience members as they emerge after watching the movie.
&;We do not want to embarrass the movie-goers by nabbing them, so the volunteers are instructed not interact or question them,&; said Anant.
Gujarat is home to many large industries such as textiles and chemicals, employing more than eight million migrant workers who come from neighboring states in search of a better life.
Screening and selling of pornographic films is illegal but the law is rarely enforced.
Maternal mortality highest in South Sudan UNFPA
Wed, 06 Jun 2007 15:52:45 GMTBy Skye Wheeler
JUBA, Sudan - Rates of pregnancy-related deaths in south Sudan are the highest in the world, a United Nations Population Fund official said.
&;Rates are actually at 2,030 per 100,000 births, the worst in the world,&; UNFPA's South Sudan head Dragudi Buwa said.
A 2005 peace deal ended more than two decades of civil war between the north and the south, and created a semi-autonomous southern government. But the south has few medical facilities for its population, estimated at about 10 million.
In north Sudan, rates of maternal mortality are 509 deaths per 100,000 births, according to the United Nations.
&;Skilled care attendance at birth is under five per cent,&; Buwa added.
A lack of trained midwives, coupled with high rates of early marriage and pregnancy and a lack of health facilities and medical advice was responsible for the large number of pregnancy-related deaths, Buwa said.
UNFPA, which is about to release a report on the findings, estimates the teen birth rate to be at 200 per 1,000 births.
Buwa said researchers found many mothers as young as 13 and many 19-year-olds who had already had up to four children.
According to information gleaned from south Sudanese health facilities, hemorrhaging accounted for 25 percent of all maternal deaths.
&;A normal blood banking system would mean at any time blood of different types would be available. What happens here is that there's nothing in the stores,&; said Buwa.
Buwa said between 7 and 9 percent of blood donations screened at facilities was found to be HIV positive.
