Mammography most effective one year after breast cancer treatment
Washington, November 26: The recipients of breast cancer therapy may not require a follow-up mammogram until 12 months after radiation, according to a new study.
Researchers at the University of California, Los Angeles, and the University of California, San Diego, set out to determine whether the recommended timeframe for a post-treatment mammogram offers any benefit to patients.
It is significant to note here that current American Society of Clinical Oncology (ASCO) and National Comprehensive Cancer Network (NCCN) guidelines recommend follow-up mammograms at between six and 12 months after radiation.
During the study, the researchers looked at 408 patients who were treated with breast-conserving therapy and radiation between 1995 and 2005, and who had follow-up mammograms at UCLA within one year after completing radiation.
The median interval between radiation and the initial mammogram was 3.1 months.
The researchers found that only 10 patients had suspicious findings on their mammograms, and that only two of them were found to have recurrent cancer.
Both cases were non-invasive ductal carcinomas, they revealed.
Considering that only 0.49 recurrences were detected per 100 mammograms, and that only non-invasive ductal carcinoma was found, the researchers came to the conclusion that mammograms should not be performed until at least one year after radiation.
The cost of a mammogram is about 115 dollars, and many women can experience moderate to severe pain during the procedure and high levels of anxiety during a needle biopsy.
The researchers say that not performing mammograms for one year after the treatment can help avoid medical and psychological costs associated with mammography.
"Omitting the initial post-radiotherapy examination may improve the psychological well-being of patients, especially for women who have already been shown to have breast cancer," said Dr. Kevin Lin, lead author of the study and a radiation oncologist at Advanced Oncology Center in West Covina, California.
The study has been published in the International Journal of Radiation Oncology Biology Physics. (ANI)
'AIDS can be eliminated in 10 years'
LONDON: The virus that causes AIDS could theoretically be eliminated in a decade if all people living in countries with high infection rates are
regularly tested and treated, according to a new mathematical model.
It is an intriguing solution to end the AIDS epidemic. But it is based on assumptions rather than data, and is riddled with logistical problems. The research was published online on Tuesday in the medical journal, the Lancet.
"It's quite a startling result," said Charlie Gilks, an AIDS treatment expert at the World Health Organization and one of the paper's authors. "In a relatively short amount of time, we could potentially knock the epidemic on its head."
Gilks and colleagues used data from South Africa and Malawi. In their model, people were voluntarily tested each year and immediately given drugs if they tested positive for HIV, regardless of whether they were sick. Within 10 years, HIV infections dropped by 95%. Other initiatives like safe sex education and male circumcision were also used.
The strategy would cut the estimated number of AIDS deaths between 2008 and 2050 by about half, from about 8.7 million to 3.9 million, leaving only sporadic HIV cases. Experts think the strategy's cost would peak at about $3.4 billion a year, though expenses would fall after an initial investment.
"This is certainly beyond the bounds of the current infrastructure for many countries, but that is not a reason not to think big," said Myron Cohen, of the University of North Carolina, who has done similar research.
Only 3 million people are currently on AIDS drugs. Nearly 7 million people are still awaiting treatment, and about 3 million more people were infected last year. Worldwide, WHO guesses that about 33 million people have HIV. Increasing access to testing and drugs would stretch already weak health systems in Africa, which has most of the world's HIV cases.
WHO emphasized that the study findings do not signal a policy change. "This is only a theoretical exercise," said Kevin De Cock, director of WHO's HIV/AIDS department. He said WHO would hold a meeting next year to study the idea more closely.
Structure of key heart protein 'found'
Friday, November 28, 2008, (Washington): Scientists have discovered how a key protein in heart muscle actually works to regulate heart function, a breakthrough which they claim should help find out why it goes wrong.
An international team has shown how this cardiac protein interacts with actin, one of the two filament -forming muscle proteins (the other is myosin) that slide past each other to create the rhythmic contraction and relaxation that causes the heart to beat.
"Understanding the structure of this heart protein -- called cardiac myosin-binding protein C -- and how it attaches to actin, gives us an insight into how it actually works to modulate heart contractions.
"There's a lot of interest in cardiac myosin-binding protein C, because of its influence on fine-tuning heart muscle contractions and its links to familial hypertrophic cardiomyopathy -- an inherited cardiac disorder that affects one in 500 adolescents and young adults.
"Young people with familial hypertrophic cardiomyopathy have a gradual thickening of the ventricle walls of their hearts and a correlated increase in the risk of heart failure," said lead researcher Prof Jill Trewhella of the University of Sydney.
Experimental drug shows promise against latent TB bacteria
Washington, Nov 28 : Researchers from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, have determined how a promising drug candidate attacks the bacterium that causes tuberculosis (TB).
The finding could help scientists develop ways to treat dormant TB infections, and suggests a strategy for drug development against other bacteria as well.
One-third of the world's population is infected with Mycobacterium tuberculosis (M. tb), the bacteria that cause TB.
In a previous study, lead author Clifton E. Barry, III, Ph.D., of the National Institute of Allergy and Infectious Diseases (NIAID), and his colleagues found that M. tb mutants lacking a specific bacterial enzyme were resistant to PA-824, but at that time, they did not know the function of the enzyme.
"It took several years, but at last we were able to recreate in the test tube what happens inside mycobacterial cells when the bacterial enzyme, which we named Ddn, and a second bacterial component called a cofactor, interact with PA-824," said Barry.
They found that the key event in PA-824 metabolism is the production of nitric oxide (NO) gas.
"This highly reactive molecule is akin to a bomb blast that kills the bacteria from within," he added.
No gas is produced naturally by certain immune system cells after they engulf M. tb or other bacteria. This is one way that people with healthy immune systems can contain M. tb infection.
However, this natural immune response is not always enough to completely rid the body of TB bacteria. In essence, PA-824 performs similarly to the No-producing immune cells--but the drug's effect is more specific and triggered only after it enters the bacteria.
The non-dividing M. tb bacteria characteristic of latent TB infections are walled off by immune cells that aggregate around the bacteria to form a body called a granuloma. Oxygen levels are low inside granulomas.
In the new study, the researchers observed that No-generation during PA-824 metabolism is greatest when oxygen levels are low. This observation suggests how PA-824 may work against non-dividing M. tb. PA-824 was originally designed to work best under aerobic, or oxygenated, conditions.
Barry said that with this new understanding of how the bacterial enzyme and cofactor act on PA-824 under low-oxygen conditions, scientists could design drugs with a chemical structure similar to PA-824 but optimize them from the start to behave best under low-oxygen conditions.
The study is published in the Nov. 28 issue of Science. (ANI)
Booster vaccine for parents could protect infants from whooping cough
London, Nov 28: A booster vaccination for parents of new babies and other household members can significantly protect infants against the fatal form of whooping cough, say doctors.
Citing examples of two fatal cases of invasive pertussis in unvaccinated young infants, paediatricians Royal Hospital for Sick Children in Edinburgh explained the how infectious adults within a family can be the source of infection for unimmunised infants, reports the British Medical Journal.
In the first case, a one-month old boy was suffering from cough, runny nose and difficulty feeding for the past five days. Both parents, and an elder sibling also reported persistent coughing with vomiting in the previous two weeks.
While the elder sibling was fully vaccinated, there was no record of the parents' childhood vaccination status, but the mother received a pertussis booster in 1986.
Despite maximum therapy, the 1-month-old infant died within 24 hours.
In another case of a six-week old girl, who also suffered from history of cough and breathlessness, the doctors found that her mother had a persistent cough for more than two weeks.
While the mother had received all her childhood immunisations including pertussis, there was no record of the father's pertussis immunisation.
Despite maximum therapy, the infant died within 30 hours.
The doctors suggested that most infants catch the disease from affected household members, with parents accounting for more than half of the cases.
The author suggests that the introduction of an adult booster or more targeted vaccination of household contacts of young infants should be considered. (ANI)
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