Faster, more efficient method for detecting illegal steroids in urine
Amid growing concerns about sports "doping," researchers in Indiana and China report development of a faster and more efficient method for detecting the presence of illegal anabolic steroids in urine. Their new method, which takes only a few seconds and involves no time-consuming sample preparation, will be described in the Nov. 1 issue of ACS' Analytical Chemistry, a semi-monthly journal.
The study notes that use of banned substances by professional athletes to build muscle and gain a competitive advantage is a growing problem in sports such as track and field, baseball, football and cycling. Although effective methods exist for detecting the presence of illegal steroids in urine, current methods are time-consuming and involve cumbersome preparation steps.
Zheng Ouyang, R. Graham Cooks, and colleagues developed a new steroid-testing method that combines two state-of-the-art testing techniques called desorption electrospray ionization (DESI) and tandem mass spectrometry. In laboratory studies, the researchers used it to analyze fresh urine samples for the presence of tiny amounts of seven different anabolic steroids. The new method accurately identified the steroids in only a few seconds using only a single drop of urine, they say.
"Rapid Screening of Anabolic Steroids in Urine by Reactive Desorption Electrospray Ionization"
Contact:
Zheng Ouyang, Ph.D.
Purdue University
West Lafayette, Indiana 47907
Toward a better drug for treating muscle, bone loss in elderly men
The search for alternatives to steroid medications for treating millions of Baby Boomer males with age-related declines in the sex hormone testosterone has led researchers in California to report development of a nonsteroidal compound that shows promise as a new treatment for loss of muscle mass, bone tissue, and other problems linked to low testosterone. Their study will appear in the Oct. 18 issue of the ACS' Journal of Medicinal Chemistry, a bi-weekly publication.
In the report, Arjan van Oeveren and colleagues point out that the potential side effects of testosterone, a steroid medication, limit its use to older men with low testosterone levels. Testosterone replacement therapy may increase the risk of prostate cancer and stroke, for instance, and cannot be given orally. People take it via skin patches or rub-on gels.
The new study describes a nonsteroidal compound that in lab rats attaches to testosterone receptors in cells and triggers the same desired effects as actual testosterone in tests in laboratory animals. In comparison to other testosterone replacement treatments, the compound showed similar improvement in muscle mass and strength while having little effect on the prostate, the researchers say. It also significantly improved bone density and strength in the lab rats.
"Substituted 6-(1-Pyrrolidine) quinolin-2(1H)-ones as Novel Selective Androgen Receptor Modulators"
Contact:
Arjan van Oeveren, Ph.D.
Discovery Research, Ligand Pharmaceuticals Inc.
San Diego, Calif. 92121
Early detection of human papilloma and other viral infections
Scientists in Iowa are reporting development of a new, amazingly sensitive method for identifying the earliest stages of infection with human papilloma virus (HPV), a common virus that can increase the risk of cervical cancer in women. The test also has the potential for early identification of infection with other so-called DNA viruses, which cause a range of diseases that includes genital herpes and hepatitis. Their report is scheduled for the Nov. 1 issue of ACS' Analytical Chemistry, a semi-monthly journal.
In the study, Edward S. Yeung and colleagues point out that the most sensitive existing test for viral infections has drawbacks. That test is the Nobel Prize-winning polymerase chain reaction (PCR), used to detect DNA in settings ranging from medical labs to crime scenes. PCR requires an initial step in which scientists "amplify," or copy, a DNA sample a thousand-fold before virus detection can begin. However, amplification increases the risk of false-positives and false-negatives, especially when a sample has even a tiny amount of contaminants. Since over 50 million Pap smears are performed in the United States each year to test for HPV -- the leading cause of cervical cancer -- a fast, simple, accurate diagnosis is essential.
The new method skips the amplification step entirely, and yet can detect the presence of less than two copies of HPV per cell -- a level corresponding to very early infection. The technique, called single-molecule spectroscopy, could be easily integrated into the Pap smear method. "It can become a good clinical screening or quantification method for viral DNA in cells," opening the door to improved screening tests for hepatitis B, herpes and other diseases.
"Single-Molecule Detection of Surface-Hybridized Human Papilloma Virus DNA for Quantitative Clinical Screening"
Contact:
Edward S. Yeung, Ph.D.
Iowa State University
Ames, Iowa 50011
Fresh fruits and vegetables retain antioxidants long after purchase
The next time you think about throwing out those aging strawberries or very ripe grapes, consider this: Belgian scientists report that fruits and vegetables do not lose any antioxidant content in the days after purchase, even as tell-tale signs of spoilage appear. In some cases, antioxidant levels actually rise.
The study will appear in the Oct. 17 issue of ACS' Journal of Agricultural and Food Chemistry, a bi-weekly publication.
The life of a post-harvest fruit or vegetable is traditionally defined in terms of visual appearance and texture. While this is good for aesthetics, these benchmarks disregard flavor and nutritional quality -- especially with regards to antioxidants, which are affected by genetic, technological and environmental factors. "No important studies were done to evaluate the influence of storage on antioxidant capacity," the authors said.
To that end, Claire Kevers and colleagues obtained various produce from the Belgian market, measuring its initial antioxidant content. They then stored the fruits and vegetables at room temperature or refrigerated them at 39 degrees Fahrenheit, checking antioxidant levels at various times until the produce presented visual spoilage. The results showed that, in the days following purchase, fruits and vegetables do not lose any phenolic compounds, ascorbic acid or flavonols -- a trio of chemical classes associated with antioxidant content. "Better, in some cases, an increase on the antioxidant capacity was observed in the days following their purchase, accompanied by an increase in phenolic compounds," the researchers state.
"Evolution of Antioxidant Capacity during Storage of Selected Fruits and Vegetables"
Contact:
Claire Kevers, Ph.D.
University of Liege
Liege, Belgium
The American Chemical Society -- the world's largest scientific society -- is a nonprofit organization chartered by the U.S. Congress and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.
Source: Michael Woods
American Chemical Society
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