Health Related News From The American Chemical Society

Main Category: Biology / Biochemistry
Also Included In: MRI / PET / Ultrasound;  Water - Air Quality / Agriculture;  Infectious Diseases / Bacteria / Viruses
Article Date: 16 Aug 2007 - 18:00 PDT

email to a friend   printer friendly   opinions  

Toward prevention of a common complication of cataract surgery

A newly developed method for coating the intraocular lenses (IOLs) used in millions of cataract surgery procedures may prevent a common complication of cataract surgery, according to a report published in ACS' Biomacromolecules, a monthly journal. Such surgery corrects the vision loss that occurs when the lens of the eye becomes clouded.

Christine Jerome and colleagues report development of a method for applying a polyethylene glycol coating to IOLs. In laboratory experiments, researchers showed that the coating reduced accumulation of the protein film and adhesion of cells responsible for formation of secondary cataracts. The coating did not affect the optical properties of the lens. It also could be applied to certain other surfaces in order to discourage undesirable protein accumulation and adhesion of cells, the report states.

During the operation, a small incision in the front of the lens capsular bag is used to remove the clouded crystalline lens. The IOL is inserted into the empty capsular bag. Researchers noted that IOL replacement surgery is a safe and well-established procedure to correct the vision loss from a cataract. In about 25 percent of cases, however, the back portion of the capsule eventually becomes clouded with a 'secondary' cataract. Jerome notes that treatment is available for secondary cataracts, but describes it as risky

"Improved Performances of Intraocular Lenses by Poly(ethylene glycol) Chemical Coatings"

CONTACT:
Christine Jerome, Ph.D.
University of Liege
Liege, Belgium

Easing concerns about a promising new medical imaging agent

In a study that eases concern about the toxicity of nanoparticles being considered for use in medical imaging and biomedical research, scientists in North Dakota are reporting 'no significant toxic effects' from tests of silica nanoparticles. It is published in ACS' Chemical Research in Toxicology, a monthly journal.

Min Wu and Julia Xiaojun Zhao and colleagues point out that scientists hope to use several kinds of nanomaterials that luminesce, or glow, in clinical medicine and biomedical research. Those materials might, for instance, become a new generation of imaging agents that pinpoint the location of diseased tissue in the body. "However, the question of whether these nanomaterials are toxic to living cells or organisms has not been fully answered," the researchers explain.

The scientists used laboratory tests on human lung cells to show that luminescent silica nanoparticles did not damage cellular DNA. "Our study indicates that the luminescent silica nanoparticle is a promising labeling reagent for various biomedical applications," the study concluded, citing the need for further research on potential long-term toxicity.

"Toxicity of Luminescent Silica Nanoparticles to Living Cells"

Min Wu, Ph.D.
University of North Dakota
Grand Forks, North Dakota 58202
Julia Xiaojun Zhao, Ph.D.

Explosive discovery on genetically engineered tobacco plant

Tobacco may be bad for human health, but a new study reports that a genetically engineered tobacco plant may be very good for the environment. It shows promise for cleaning up soil contaminated with TNT, a widely used military explosive. The study is published in ACS' Environmental Science & Technology, a semi-monthly journal.

Neil C. Bruce and colleagues noted that TNT contamination is a major environmental problem at many World War II sites, military training areas, and explosive manufacturing sites. In addition to being explosive, TNT is toxic and a human health threat. Researchers knew that certain soil bacteria could metabolize and change trinitrotoluene (TNT) into nontoxic compounds. But those natural bacteria exist at levels too low to detoxify TNT.

In the new study, researchers inserted a gene for a TNT-transforming bacterial enzyme into a tobacco plant. Then they tested the plant's effect on TNT-contaminated soil in comparison to regular tobacco plants grown in the same soil for several weeks. The genetically modified plants significantly reduced the toxicity of the TNT-contaminated soil.

"This is the first report to demonstrate that transgenic plants engineered for the phytoremediation of organic pollutants can increase the functional and genetic diversity of the bacterial community in acutely polluted soil compared to wild type plants," the report states. "Our findings have important implications, not only for use of genetically engineered plants for TNT remediation, but for cleaning up other sources of contamination as well."

"Impact of Transgenic Tobacco on Trinitrotoluene (TNT) Contaminated Soil Community"

CONTACT: Neil C. Bruce, Ph.D.
University of York
United Kingdom

Fast, accurate sensor to detect food spoilage

Amid growing concern about outbreaks of food poisoning, researchers in South Carolina are reporting development of a new 'food freshness sensor,' for fast, accurate detection of food spoilage. Their study is published in ACS' Organic Letters, a bi-weekly journal.

In the study, John Lavigne and colleagues describe the need for better sensors that can detect food spoilage caused by E. coli, Salmonella, and other disease-causing bacteria. Existing methods, such as 'electronic noses' and 'electronic tongues,' require expensive equipment, are time consuming and involve complicated analyses.

In the study, they describe development of a polymer material that raises a red flag, changing color in the presence biogenic amines, compounds produced by the bacterial decay of food proteins. In laboratory tests, the polymer identified and distinguished between 22 different kinds of key food-spoilage amines with 97 percent accuracy. Researchers also used the polymer to check the freshness of a tuna by detecting the amount of amines present in the sample. "The sensitivity of the described assay is better than the typical mammalian sense of smell and is able to detect this nonvolatile amine at hazardous levels before the fish would begin to smell rancid," the report states. The approach also shows promise for detecting spoilage in other food types, it adds.

"A Food Freshness Sensor Using the Multistate Response from Analyte-Induced Aggregation of a Cross-Reactive Poly(thiophene)"

CONTACT:
John J. Lavigne, Ph.D.
University of South Carolina
Columbia, South Carolina


Toward real-world Star Trek tricoder devices

So you drop by the store tonight and buy the latest model of a Star Trek tricoder-type device -- a handheld instrument for scanning alien environments -- and use it to check your home air for indoor pollutants. As farfetched as that idea may seem, such devices are inching closer to reality, according to an article (http://pubs.acs.org/cen/business/85/8533bus1.html) published in Chemical & Engineering News (C&EN), ACS's weekly newsmagazine.

The article, by C&EN Senior Correspondent Marc Reisch, explains that scientific instrument makers are in the midst of an effort to expand their traditional markets, moving instruments like mass spectrometers and infrared photometers out of the lab and into the hands of the average consumer. In a world that fears terrorists, contaminated food, and airborne pollutants, instrument companies are working to design portable, inexpensive, user-friendly devices that can do the work of those laboratory mainstays, Reisch writes. An executive of one major instrument maker, quoted in the article, predicts that such instruments will be available to consumers, including Star Trek-like devices that serve as personal environmental scanners.

"Given the proliferation of instruments alongside manufacturing lines and in battle zones, office buildings, and refineries, it just might be feasible for a consumer to walk into Home Depot someday and buy a device that today only a scientist or quality control expert would want to have," the article concludes.

FOR ADVANCE INFORMATION, CONTACT:
Michael Bernstein
ACS News Service

234th ACS National Meeting, August 19-23, Boston, MA
The 234th ACS national meeting will be held in Boston, Mass., on August 19-23, 2007, at the Boston Convention and Exhibition Center and more than a dozen hotels across the city. More than 15,000 scientists and others are expected to attend this scientific extravaganza. There will be more than 9,500 presentations on new discoveries in chemistry, health, medicine, energy, environment, food, and other fields. The theme: "Biotechnology for Health and Wellness."

###

Source: Michael Woods
American Chemical Society

• Additional
• References
• Citations