World Bulletin/News Desk
Egg cells can repair themselves from damage caused by radiation far better than doctors ever thought, a finding researchers say gives fresh hope in protecting women undergoing cancer therapy from infertility.
Although the experiments have only been in mice, researchers believe they have relevance for female cancer patients and women who suffer premature menopause, a condition that puts them at risk of early infertility, osteoporosis and heart disease.
In a paper to be published in the November 9 issue of the journal Molecular Cell, scientists in Australia found that egg cells, or oocytes, are killed not by radiation, but by two proteins -- puma and noxa -- which snap into action when they detect DNA damage to egg cells.
In experiments using mice that did not carry these proteins, the scientists found that their eggs survived radiation and they went on to produce normal offspring.
"This is very exciting. It means if you get rid of those proteins that kill, the oocytes or specialised egg cells can actually repair their DNA and that has never been known before," said lead author Clare Scott, an associate professor and oncologist at The Royal Melbourne and Royal Women's Hospitals.
Between 50 to 80 percent of eggs survived in these mice.
"These were enough to result in normal fertility in those mice and they could produce normal pups. Those pups went on to be fertile themselves and lived a normal lifespan with no evidence of tumours or other abnormalities," she said by telephone.
Scott's colleagues are conducting similar trials on human egg cells to see if the two proteins work in the same way. If all goes well, they hope a drug can be designed to block the two proteins from killing egg cells.
"If that pans out well, then we would hope that a drug that could target (the protein) puma ... be provided as a therapy for three to six months during cancer therapy," Scott said.
Such a drug that blocks the action of the proteins could possibly prevent premature menopause or infertility, she added.
"In a woman, premature menopause is caused by (early) death of specialised egg cells. And if you can get specialised egg cells to survive, then premature menopause won't occur."
The United Nations is hoping to raise $400 million over two years to reduce the current cholera caseload of 30,000 to 10,000 by the end of 2018 and provide clean water and sanitation.
Steven Cooke, a biology professor at Carleton University in Ottawa, says that the very tools used by scientists to study and protect animals and fish are being hijacked to do just the opposite.
Matthew Mitchell was helping his dad clear out the back shed at their home north of Sydney when he was bitten on the finger by a funnel-web spider, that had been lurking in his shoe.
The study found that about a third of antidepressants are prescribed for conditions other than depression.
Virtually all of the kingdom's power currently comes from crude, refined oil or natural gas.
At least 269 human infections reported in country since January, with at least 87 fatalities, according to state media
The appropriately named robusta coffee comes from the Coffea canephora plant, which is being increasingly planted in the Central American country under government authorization.
In a trial, MRI scans revealed which infant brains were growing at a faster-than-normal rate -- a telltale sign of autism spectrum disorder (ASD), they wrote in the science journal Nature.
New study indicates fasting for 5 days per month can also lower blood pressure
Gene editing should only be used to prevent suffering, international group of scientists asserts
Kenya, Tanzania and Uganda outperformed their peers in access to energy, while Pakistan made progress on renewable energy, and Vietnam had developed policies on energy efficiency.
Doctors call 48-hour job action to protest jailing of 7 doctors union leaders
In total, an estimated 666 whales were stranded in two pods on Friday and Saturday at Farewell Spit, on the northern tip of the South Island.
Fishermen blame the national power firm Elektroprivreda BiH, which manages the Jablanica dam and the hydroelectric power station about 30 kilometres west of the lake.
One fallout of the war in Yemen has been a slump in agricultural production across the country, contributing to soaring malnutrition.
Quinoa thrives at any altitude up to 4,000 metres (13,000 feet) above sea level, in conditions that would leave most food plants struggling.