In this edition:
- Researchers Report Advances in Cell Conversion Technique
- Marijuana Ingredient May Fight Bacteria
- Researchers See Promise in New Test for Tumors
Researchers Report Advances in Cell Conversion Technique
Biologists at Harvard have converted cells from a mouse’s pancreas into the insulin-producing cells that are destroyed in diabetes, suggesting that the natural barriers between the body’s cell types may not be as immutable as supposed.
This and other recent experiments raise the possibility that a patient’s healthy cells might be transformed into the type lost to a disease far more simply and cheaply than in the cumbersome proposals involving stem cells.
The new field depends on capturing master proteins called transcription factors that control which sets of genes are active in a cell and thus what properties the cell will possess. Each type of cell is thought to have a special set of transcription factors.
Last year a Japanese biologist, Shinya Yamanaka, showed that by inserting four transcription factors into an adult cell he could return it to its embryonic state.
In a variation of this technique, a team led by Qiao Zhou and Douglas A. Melton at Harvard has now identified three transcription factors active in the insulin-producing beta cells of the pancreas.
They hitched the genes for these three factors onto a virus that infects another type of pancreatic cell, known as an exocrine cell. In mice made diabetic by a drug that kills beta cells, the transformed exocrine cells generated insulin, allowing the mice to enjoy “a significant and long-lasting improvement” in their diabetic state, the researchers are reporting Thursday in the journal Nature.
Many steps remain before the technique could be considered for human use.
Besides producing insulin, the transformed exocrine cells looked like beta cells and ceased making proteins typical of exocrine cells. But they did not organize themselves into the pancreatic structures known as islets where beta cells usually cluster. The researchers claim only to have made “cells that closely resemble beta cells.”
Even so, Robert Blelloch, a cell biologist at the University of California, San Francisco, said, the Harvard experiment was “a very nice story — it’s pretty impressive that you can make such a switch just by adding three factors to a quite different cell type.”
Last month Patrick Seale and Bruce Spiegelman of the Dana-Farber Cancer Institute in Boston showed how with a single transcription factor they could make white fat cells generate brown fat cells, a very different type of cell. source
My comment: I'm very happy for this progress, although I just need to point out that the question of why the new cells didn't follow that structure the ought to have followed is not trivial and should be heavily studied. This is important, because the resemblance is not safe enough for the body if they show different behaviour. This could lead to more harm than good and should be carefully examined!
And one more thing, imagine that by some mechanism the mind can influence the body to activate genes on need-base. Wouldn't that explain some miracles? Won't that be fun :)
Marijuana Ingredient May Fight Bacteria
Marijuana may be something of a wonder drug — though perhaps not in the way you might think.
Researchers in Italy and Britain have found that the main active ingredient in marijuana — tetrahydrocannabinol, or THC — and related compounds show promise as antibacterial agents, particularly against microbial strains that are already resistant to several classes of drugs.
It has been known for decades that Cannabis sativa has antibacterial properties. Experiments in the 1950s tested various marijuana preparations against skin and other infections, but researchers at the time had little understanding of marijuana’s chemical makeup.
The current research, by Giovanni Appendino of the University of the Eastern Piedmont and colleagues and published in The Journal of Natural Products, looked at the antibacterial activity of the five most common cannabinoids. All were found effective against several common multi-resistant bacterial strains, although, perhaps understandably, the researchers suggested that the nonpsychotropic cannabinoids might prove more promising for eventual use.
The researchers say they don’t know how the cannabinoids work, and whether they would be effective as systemic antibiotics would require much more research and trials. But the compounds may prove useful sooner as a topical agent against methicillin-resistant Staphylococcus aureus, or MRSA, to prevent the microbes from colonizing on the skin. source
My comment: I wonder if by smoking it, you can fight bacteria in the lung. Because that could prove very useful in cases of severe pneumonias or other lung infections. Although I remember reading that Marijuana isn't good for the lung because it increased a pressure of a kind in it. That's very very interesting. /I really speak from non-hallucinogen point of view, I've never smoked weed, so I don't care about that/
Researchers See Promise in New Test for Tumors
MILWAUKEE (AP) — A radioactive tracer that “lights up” cancer hiding inside dense breasts showed promise in its first big test against mammograms, revealing more tumors and giving fewer false alarms, doctors reported Wednesday.
The experimental method, molecular breast imaging, or M.B.I., would not replace mammograms for women at average risk for cancer. But it might become an additional tool for higher-risk women with a lot of dense tissue that makes tumors hard to spot on mammograms, and at a lower cost than magnetic resonance imaging, or M.R.I. About one-fourth of women 40 and older have dense breasts.
Mammograms, a type of X-ray, are now the chief way to check for breast cancer. M.B.I. uses radiation, too, but in a different way. Women are given an intravenous dose of a short-acting tracer that is absorbed more by abnormal cells than by healthy ones. Special cameras collect the “glow” these cells give off, and doctors look at the picture to spot tumors.
Researchers tried both methods on 940 women who had dense breasts and a high risk of cancer because of family history or other reasons.
Thirteen tumors were found in 12 women: eight by M.B.I. alone, one by mammography alone, two by both methods and two by neither. (The two missed tumors were found on subsequent annual mammograms, physical exams or other imaging tests.)
Looked at another way, M.B.I. found 10 of 13 tumors, missing 3; mammograms detected 3 of 13 tumors, missing 10. Using both methods, 11 of 13 tumors would have been detected.
“These images are quite striking,” Ms. Hruska said. “You can see how the cancers would be hidden on the mammograms.”
Mammograms gave false alarms — leading doctors to conclude that cancer was present when it was not — in about 9 percent of patients, compared with 7 percent for M.B.I. The M.B.I. tests led to more biopsies than mammograms did, but they more often revealed cancer.
The Susan G. Komen for the Cure foundation and Bristol-Myers Squibb, which makes the imaging agent used in the study, paid for the work.
The next test will be to see how M.B.I. stacks up against M.R.I. The federal government is paying for a new study Mayo is leading that compares the two in 120 high-risk women with dense breasts.
M.R.I. is often used now for women with dense breasts, but it gives many false alarms that lead to unnecessary biopsies. Doctors hope the new test will prove more accurate and cost less — under $500, compared with more than $1,000 for an M.R.I.
One drawback of M.B.I.: It uses about 8 to 10 times the radiation of mammograms, a dose that engineers like Ms. Hruska are trying to lower with newer technology. Other medical centers also are testing M.B.I. source
My comment: That is a great new technology! I hope the would lower the radiation also and thus they will make it very very useful. It's great, really, because early detection of breast cancer increases dramatically the chances of survival.