Monday, May 31, 2010

Plectasin - a new weapon against highly resistant microbes ?..

We know that Plectasin, found in Pseudoplectania nigrella (see picture), is the first defensin to  be isolated from a fungus. Plectasin has a chemical structure resembling defensins found in spiders, scorpions, dragonflies and mussels. In laboratory tests, Plectasin was especially active in inhibiting the growth of the common human pathogen Streptococcus pneumoniae, including strains resistant to conventional antibiotics. Plectasin has a low toxicity in mice, and cured them of peritonitis and pneumonia caused by S. pneumoniae as efficiently as vancomycin and penicillin, suggesting that it may have therapeutic potentia.

Now researchers lead by Prof. Dr. Hans-Georg Sahl of   Universities of Bonn, Utrecht, Aalborg and of the Danish company Novozymes AS have shed light on how the substance Plectasin,  destroy highly resistant bacteria. As per the claim by the researchers Plectasin binds to a cell-wall building block called lipid II and thus prevents it from being incorporated and thus disrupting the forming of the cell wall in bacteria so that the pathogens can no longer divide. 

In this process, plectasin behaves like a thief which steals the stones off a mason. 'It binds to a cell-wall building block called lipid II and thus prevents it from being incorporated ,' Professor Sahl explains. 'However, bacteria cannot live without a cell wall.' It comes as no surprise that the most famous antibiotic penicillin also inhibits cell-wall synthesis...
Researchers claims that, plectasin is more similar in its mode of action to another widely used drug, vancomycin. Vancomycin had been the drug of choice in combating MRSA strains since the 1980s. Meanwhile, though, there are more and more bacteria that are also resistant to vancomycin. 'However, these strains are still susceptible to plectasin,' Dr. Tanja Schneider emphasises. Nevertheless, there is no permanent solution to the resistance problem even with a new antibiotic . 'It is always just a question of time until the pathogens mutate and become insensitive ,' she says. 'It's a never ending arms race..' authors conclude that plectasin will be promising lead compound for new antibiotics...

Ref : http://www.sciencemag.org/cgi/content/abstract/328/5982/1168

Sunday, May 30, 2010

Healthcare associated infection prevention....

Idiom "prevention is better than cure" is  more relevant than ever, but the awareness is lacking in the healthcare associated infection prevention. I find HAI Watch   site very informative in this aspect. 

HAI Watch is the  resource for collateral and supplies to help keep the  organization aware of the importance of healthcare associated infection prevention..... 

I really appreciate the efforts like the HAI Education Program a  part of a national infection awareness campaign for healthcare professionals called “Not on My Watch” and will provide the facility with a toolkit that contains informational flyers, patient safety tips and posters. I hope the info will definitely help the healthcare professionals in protecting the patients from preventable hospital infections....

Tuesday, May 25, 2010

FDA Acceptance of New Drug Application for Vilazodone for the Treatment of Major Depressive Disorder..

Vilazodone(see structure) is an antidepressant which is currently under  development by Clinical Data for the treatment of major depressive disorder, and as of 2009 has completed two phase III clinical trials with positive results. An NDA was submitted on March 23rd, 2010 in the United States and is currently pending approval by the FDA which, if approved, will likely precede vilazodone's availability on the market by the end of 2010.

Now the company claims that FDA has accepted for filing the Company's New Drug Application (NDA) for vilazodone for the treatment of major depressive disorder (MDD).


Vilazodone is a dual-acting potent and selective serotonin reuptake inhibitor and a 5-HT1A receptor partial agonist. The NDA will be subject to a standard review. 

The acceptance of the NDA for review by the FDA is another positive step toward our goal of bringing vilazodone to market, and if approved, vilazodone will offer a novel treatment to the millions of people suffering from depression”  says Carol R. Reed, M.D., Executive Vice President and Chief Medical Officer of Clinical Data.....

Ref : http://www.clda.com/uploads/CLDA%20NDA%20acceptance%20FINAL.pdf

Tuesday, May 18, 2010

Individual's lifestyle choices can affect cholesterol, triglycerides levels: Mayo Clinic Health Letter

Sometimes, diet and lifestyle choices alone aren't enough to manage total cholesterol levels. Yet, diet and exercise are important management strategies even when cholesterol-lowering medications are indicated...
 
Individual's lifestyle choices can affect cholesterol, triglycerides levels: Mayo Clinic Health Letter

Monday, May 17, 2010

Flaxseed-fed chickens shed light on ovarian cancer.....

In continuation of my update on the benefits of  flax seeds,  I found this info interesting to share with. Researchers from College of Agricultural, Consumer and Environmental Sciences, lead by Prof. Janice Bahr, have come up with interesting info about flax seeds, i.e., hens fed a flaxseed-enriched diet for one year experienced a significant reduction in late-stage ovarian tumors.

The interesting part of the research lies in that fact that, chicken is the only animal that spontaneously develops ovarian cancer on the surface of the ovaries like humans and researchers  evaluated how a flaxseed-enriched diet affected 2-year-old laying hens (hens that have ovulated as many times as a woman entering menopause). As we know flaxseed is the richest plant source of alpha-linolenic acid, (omega-3 fatty acid). Several studies have already shown that flaxseed inhibits the formation of colon, breast, skin and lung tumors.

As per the claim by the researchers, hens fed the control diet had significantly more late-stage tumors that presented with fluid and metastases as compared to the hens fed a flaxseed diet. Though hens fed the flaxseed diet did not have a decreased incidence of ovarian cancer, they did experience fewer late-stage tumors and higher survival rates.

In addition, researchers found that hens fed the flaxseed diet had better weight control which is important because obesity increases cancer risk. Both diets had equal caloric content, however the flaxseed-fed hens weighed less at six months than the control-fed hens. But at 12 months, the flaxseed-fed hens were the same weight and the control-fed hens had loss significant weight, which was indicative of their failing health. Ultimately, the flaxseed-enriched diet helped the birds maintain a healthy weight and resulted in less sickness and death.
"Through this research, we have proven that flaxseed supplementation for one year is able to reduce the severity of ovarian cancer in hens," she said. "These findings may provide the basis for a clinical trial that evaluates the efficacy of flaxseed as a chemosuppressant of ovarian cancer in women."
Bahr believes this hypothesis is valid and is currently in the middle of a four-year study to determine if long-term dietary intervention with flaxseed will reduce the incidence of ovarian cancer development....

Ref : http://www.aces.uiuc.edu/news/stories/news5165.html

Broccoli component limits breast cancer stem cells, study finds

In continuation of my earlier blog article " Broccoli sprouts may help prevent stomach cancer !....
I found this article interesting  to sharing with...
Broccoli component limits breast cancer stem cells, study finds

Sunday, May 16, 2010

Growers can boost benefits of broccoli and tomatoes

Carotenoid-enriched tomatoes produced more bioactivity in the liver than lycopene-enriched or standard tomatoes, yielding the most cancer-preventive benefits.

In their current research, researchers from College of Agricultural, Consumer and Environmental Sciences | University of Illinois,  are experimenting with ways to increase the bioactive components in these foods in order to test the efficacy of enriched broccoli and tomatoes in a new prostate cancer study....

Growers can boost benefits of broccoli and tomatoes

Friday, May 14, 2010

PEPCK (phosphoenolpyruvate carboxykinase) a potential target for drugs that fight tuberculosis.

 In continuation of my update on tuberculosis and drug discovery ..... A new  research conducted at Weill Cornell Medical College sheds light on a previously unrecognized aspect of fatty acid metabolism that could potentially lead to new targets for drug therapy. A team led by Dr. Sabine Ehrt, professor of microbiology and immunology at Weill Cornell Medical College, reported that Mtb relies primarily on gluconeogenic substrates for in vivo growth and persistence, and that phosphoenolpyruvate carboxykinase (PEPCK see picture) plays a pivotal role in the growth and survival of Mtb during infections in mice, making PEPCK a potential target for drugs that fight tuberculosis.

Dr. Ehrt and her colleagues found a way to silence the gene encoding PEPCK in Mtb during mouse infections to assess the importance of gluconeogenesis for Mtb's ability to maintain a chronic infection.
 "Silencing a gene when the pathogen is not or only slowly replicating, after an infection has established, is an important tool for studying diseases such as TB, which can be dormant for years only to become active again years later." says Dr.Ehrt...
 It is especially challenging as the infection can lay dormant in the body even though there are no symptoms. Researchers investigated the metabolic requirements of Mtb during acute and chronic infections and found that the gluconeogenic enzyme PEPCK is critical for both.

Interestingly, the  study used a novel mass spectrometry-based metabolic profiling tool, developed at Weill Cornell (in collaboration with Agilent Technologies) by Dr. Kyu Rhee to biochemically examine Mtb carbon metabolism. As per the claim by the researchers,  the tool has provided the first direct insights into the metabolic architecture of Mtb.

 Though the current treatments used  to treat Mtb are effective, the treatment times are too long and the regimens too complex, which  leads to treatment failures (due to poor adherence and multi drug resistance).   We need new, safer drugs that work faster to eliminate tuberculosis.  Dr. Ehrt hopes that her work will eventually lead to new drug therapies to treat tuberculosis.....

Ref : http://www.pnas.org/content/early/2010/04/26/1000715107

Tuesday, May 11, 2010

Yellow fever mosquito's resistance to DEET !.....

In continuation of  my update on mosquito repellents,  I found this info  interesting to share with. We know that N,N-Diethyl-meta-toluamide, DEET (see structure), is the most common active ingredient in insect repellents. It is intended to be applied to the skin or to clothing, and is primarily used to repel mosquitoes. In particular, DEET protects against tick bites, preventing several rickettsioses, tick-borne meningoencephalitis and other tick-borne diseases such as Lyme disease. It also protects against mosquito bites which can transmit dengue fever, West Nile virus, eastern equine encephalitis, and malaria. 

Now researchers from Swedish University of Agricultural Sciences (SLU) and associates in the UK, for the first time in laboratory tests have shown that yellow fever mosquito has developed a resistance to the mosquito repellent DEET.
"Through testing, we have found that yellow fever mosquitoes no long sense the smell of DEET and are thereby not repelled by it. This is because a certain type of sensory cell on the mosquito's antenna is no longer active" says Rickard Ignell, a researcher at the Division for Chemical Ecology at SLU in Alnarp....

Rickard Ignell performed the research in collaboration with Rothamstead Research in the UK. The scientists have thus seen that the sensory cell on the mosquito's antenna has stopped reacting to DEET. This have many explanations, such as the protein that binds in to DEET having mutated. The researchers are now urging restrictiveness in the use of DEET and other mosquito repellents on a large scale in a limited area, in order not to make other mosquito species resistant. The mechanism is still to be established, but in my opinion its a interesting finding....

Ref : http://www.pnas.org/content/early/2010/04/26/1001313107