Australian team creates IVF history with ovarian
tissue transplant
Melbourne:
In a world first, an infertile Australian woman has conceived after growing new
eggs in ovarian tissue transplanted into her abdomen, a breakthrough doctors
say has the potential to revolutionise fertility treatment.
The
woman, known only by her first name, Vali, is nearly 26 weeks pregnant with
twins after previously being rendered infertile by treatment for ovarian
cancer. A team at Melbourne IVF and The Royal Melbourne Hospital managed to
help the woman grow egg follicles and produce two healthy eggs after
transplanting her own frozen ovarian tissue into her abdomen.
Only
one baby has been born before in Australia after ovarian tissue transplant, and
fewer than 30 globally, but this is the first time the tissue has been
successfully transplanted at an entirely different site in the body to where it
was taken from, the report said.
The
Royal Melbourne Hospital has collected about 300 samples from women it says
could now go on to become pregnant.
Gab
Kovacs, the international medical director of Monash IVF, which did the first
successful Australian ovarian tissue transplant, said this next breakthrough
was very exciting.
"It makes me quite convinced that the optimal way for preserving fertility will be taking ovarian tissue," he said. "If I had a patient who was going to lose their fertility to cancer treatment I would offer it from now on". Vali`s fertility specialist, Kate Stern, said it had taken years and required almost daily testing and other procedures, to achieve the pregnancy.
"It makes me quite convinced that the optimal way for preserving fertility will be taking ovarian tissue," he said. "If I had a patient who was going to lose their fertility to cancer treatment I would offer it from now on". Vali`s fertility specialist, Kate Stern, said it had taken years and required almost daily testing and other procedures, to achieve the pregnancy.
Associate
Professor Stern said she had worked closely with an oncologist to ensure that
Vali`s ovarian tissue did not have cancer cells in it, and the pioneering
procedure would now provide hope to other cancer survivors.
The
sample of Vali`s ovarian tissue was taken from her cancer-free ovary through
keyhole surgery and frozen. Seven years later, the tissue was grafted onto the
left and right sides of the front wall of her abdomen.
After
a few months the tissue started working, and with a gentle dose of hormone
treatment produced follicles and two single eggs. Both were fertilised,
implanted, and became viable pregnancies.
More than 1300 women are diagnosed with ovarian cancer in Australia each year, with about 39 per cent diagnosed in woman under 60.
More than 1300 women are diagnosed with ovarian cancer in Australia each year, with about 39 per cent diagnosed in woman under 60.
03.09.2013
How antibiotics enable pathogenic gut infections
Washington:
A new study could help pinpoint ways to counter the effects of the
antibiotics-driven depletion of friendly, gut-dwelling bacteria.
Justin Sonnenburg, PhD, assistant professor of microbiology and immunology at the Stanford University School of Medicine and the senior author of the study said that the study specifically supports the suggestion that our resident microbes hold pathogens at bay by competing for nutrients.
The particular nutrients Sonnenburg`s team looked at were sialic acid and fucose, a couple of members of the sugar family.
Researchers experimented on mice that had been born and bred in a germ-free environment. These mice`s guts were devoid of bacteria, unlike normal mice, which harbour hundreds of bacterial species in their bowels just as humans do. Into these germ-free mice the investigators introduced a single bacterial strain, Bacteroides thetaiotaomicron.
In a series of separate experiments, the investigators introduced either S. typhimurium (a salmonella strain) or C. difficile in the B. theta-loaded experimental mice.
Introducing one friendly and one pathogenic bacterial strain into the guts of the formerly germ-free mice, the scientists were able to show that, in this approximation of an antibiotic-decimated gut-microbe ecosystem, the levels of sialic acid soared to high levels in the absence of a complete set of intestinal microbes that ordinarily would keep those levels from climbing.
In the presence of these sugars and absence of competition, both pathogens were able to replicate more rapidly. B. theta generated a sialic-acid surplus that, in the absence of the other hundreds of normal bacterial species, were bequeathed to the pathogenic strains.
When
the researchers investigated the effects of antibiotics on mice with normal
intestinal ecosystems, they saw the same sialic-acid spike- and pathogen
population explosion- in the wake of the carnage.
The
study was published in journal Nature.
03.09.2013
A wild beast may wound your body, but an
evil friend will wound
your mind
Buddha
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