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Josie pasted this on the wall. We all kiasu go put our names on the paper first to *chup* places once the tables are in.
Bladders engineered in the laboratory from patients' own cells and then implanted into the body have succeeded in their first clinical trial.
The feat was accomplished by Anthony Atala, at Wake Forest University Medical School in Winston-Salem, North Carolina, and his colleagues. He says that while scientists have had success with skin transplants grown on scaffolds in the past, this is the first time they have grown and transplanted a discrete, complex organ.
The success is the culmination of an idea that the team began exploring 16 years ago. Atala adds that they are also working on growing bio-engineered hearts and pancreases in the lab.
To create the new bladders, the researchers took a biopsy from patients whose bladders functioned poorly due to an inherited nervous system disorder. The team then placed muscle cells and cells from the bladder lining on a biodegradable bladder-shaped scaffold and allowed them to grow for about two months.
The scaffolds were made of the structural protein collagen, in some cases adding polyglycolic acid, a polymer used in surgical sutures.
The team then transplanted these new bladders into their patients in a delicate operation and monitored their recovery. Two of the patients did not provide follow-up information. But Atala’s group did track the progress of seven patients, aged between 4 and 19 years, for an average of nearly four years.
The patients with the bio-engineered bladders gained better urinary control. The improvements were similar to those resulting from standard surgery that relies on intestinal grafts to fix the bladder. But the new technique does not require any damage to the intestine, the researchers note.
“Atala and his colleagues should be praised for the milestone they have reached, but further multi-institutional studies are needed with longer follow-up,” writes Steve Chung, of the Advanced Urology Institute of Illinois in Spring Valley, Illinois, in a commentary on the study appearing in the Lancet. Until then, he adds, surgery using intestinal tissue to repair the bladder “remains the gold standard”.
Bladder disease does not only cause urinary control problems but can lead to kidney damage. At present, reconstructive surgery is often performed to treat severe bladder problems.
This procedure involves grafting tissue from a section of the small intestine or stomach. But medical experts say that many complications can arise from this type of procedure.
Journal reference: Lancet (DOI: 10.1016/S0140-673(06)68438-9)
Move over bacon, now there's something healthier. A team of researchers has created a transgenic pig that produces higher-than-normal levels of beneficial omega-3 fatty acids. This could make pork a good alternative to fish for cardiovascular health, as well as provide a model system for studying the effects of these fatty acids on human diseases.
Omega-3, or n-3, fatty acids are a group of polyunsaturated fatty acids (PUFA), well known for their benefits to human health. Fish are the richest source of n-3 fatty acids, but the potential for mercury contamination makes eating some fish products risky. Researchers have tried to enhance the content of grains, but livestock have not been a viable alternative so far. Pigs, cows, and other farm animals contain low levels of n-3 fatty acids and high levels of another group of PUFAs called omega-6, or n-6, fatty acids. And that, in fact, is a problem: This high n-6/n-3 ratio is known to contribute to the incidence of diseases such as cancer, diabetes, arthritis, and depression in humans.
Now, researchers have found a way to improve this ratio. The trick was inserting a gene from the Caenorhabditis elegans worm into the pig genome. The gene, called fat-1, codes for an enzyme that converts n-6 to n-3. A team led by Yifan Dai of the University of Pittsburgh in Pennsylvania popped the gene into the DNA in pig fibroblast nuclei and transferred these fibroblast nuclei into pig oocytes. One more set of nuclear transfers later, and the team got eight transgenic piglets. The pigs produce 3 times more n-3 fatty acids and 23% less n-6 fatty acids than normal pigs, giving the new breed a 5-fold lower n-6/n-3 ratio, the researchers reported online yesterday in Nature Biotechnology.
"I just think it's a great technical achievement," says Michael Roberts, a bovine reproductive biologist at the University of Missouri (UM), Columbia, who was not associated with this study. He cautions, however, that further studies on the quality and safety of the meat, as well as the health of the cloned animals, will need to be done before people can buy heart-healthy bacon at their local supermarket. "It's going to be a long time before such animals are able to enter the food chain," he says.
For now, co-author Randy Prather of UM, says these transgenic pigs could serve as good models for studying the effects of higher n-3 fatty acid levels on cardiovascular and autoimmune diseases. Researchers may be able to determine, for example, if higher levels of n-3 fatty acids could override the harmful effects of high fat diet on the cardiovascular fitness of the pigs, he says.