Here are some of the latest health and medical news developments,compiled by editors of HealthDay:
THC Disrupts Important Brain Region
The active ingredient in marijuana -- tetrahydrocannabinol (THC) -- disrupts the area of the brain that keeps the lid on inappropriate thoughts and behaviors, such as swearing and paranoia, a British study concludes.
Using brain scans, Institute of Psychiatry researchers found that volunteers who took THC capsules showed reduced activity in the inferior frontal cortex, BBC News reported. The effects of THC on this brain area were short-term, but some people appeared to be more vulnerable than others.
The research offered strong evidence that marijuana has a strong impact on the brain, the scientists said. However, they noted it wouldn't be ethical or feasible to study the long-term effects of THC on the brain.
The findings were to be presented this week at an Institute of Psychiatry conference. A second study to be presented at the conference found that another ingredient in marijuana -- cannabidiol (CBD) -- can help control psychotic symptoms and may prove useful in the development of new treatments, BBC News said.
Bullfrog Compound Helps Kill Hospital 'Superbug'
A substance produced by American bullfrogs helps kill methicillin resistant staphylococcus aureus (MRSA) bacteria, the so-called "superbug" that often infects people in hospitals and long-term care.
Researchers at St. Andrews University in Scotland developed a treatment that kills MRSA and a key ingredient is ranalexin, an antimicrobial peptide found in bullfrogs, BBC News reported. The treatment includes another antimicrobial compound called lysostaphin.
"Our finding represents a potentially novel way to combat MRSA via surface treatment or impregnation of wound dressings," said research team leader Dr. Peter Coote, a microbiologist with the university's Centre for Biomolecular Science.
"The development of new routes to target MRSA that do not result in the acquisition of resistance would greatly improve the ability of clinicians to tackle these infections more effectively and cheaply," Coote said.
Techniques learned from the research, published by the British Society for Antimicrobial Chemotherapy, have already been patented, BBC News reported.
Trans Fat Eliminated in KFC Chicken
KFC restaurants announced Monday that all 5,500 of its U.S. outlets have stopped using artery-clogging trans fat to fry chicken, the Associated Press reported.
Last October, the Louisville, Ky.-based chain said it was switching to a new soybean oil. The new cooking oil will not change the taste of the fried chicken, a company spokesman said.
While KFC's chicken won't have any trans fat, some of its non-fried items -- including pot pies, biscuits, macaroni and cheese, and some desserts -- still contain trans fat. The company said it's trying to find ways to remove trans fat from those menu items, the AP reported.
Also on Monday, Taco Bell said all of its U.S. restaurants have switched to an oil with no trans fat. KFC and Taco Bell are subsidiaries of Yum Brands Inc.
Laws to ban trans fat in restaurants have been passed by New York City and Philadelphia and a number of states have introduced bills to ban trans fat in school cafeterias and restaurants, the AP reported.
U.S., China Resist Climate Change Plan
A proposed international plan to combat climate change is facing resistance from the United States and China. The two countries claim that measures to reduce greenhouse gas emissions will be more costly and take longer than scientists claim, the Associated Press reported.
According to documents obtained by the AP, the U.S. and China also play down the benefits of reducing greenhouse gas emissions.
The proposed plan was created by the Intergovernmental Panel on Climate Change (IPCC), a United Nations network of 2,000 scientists. Over the last few weeks, government officials have been reviewing the draft plan and will meet this week to discuss it with the scientists.
The IPCC plan says that the world can reduce greenhouse emissions below current levels by shifting away from carbon-laden fuels like coal and oil, investing in energy efficiency, and implementing agricultural reforms, the AP reported.
In order to take effect, the draft plan must be unanimously approved by more than 120 governments and all changes to the plan must be accepted by the IPCC scientists.
Chinese Herbal Compound May Treat Kidney Cysts
A compound derived from a traditional Chinese medicine may reduce the incidence of kidney-destroying cysts in people prone to the illness, researchers report.
A Yale University team led by Dr. Craig Crews tested the compound, called triptolide, in mice bred to have a disease similar to human polycystic kidney disease. Triptolide is found naturally in Lei Gong Teng, a medicinal herb used for centuries in China to fight cancer, inflammation and auto-immune disorders.
In polycystic kidney disease, genetic signals that normally inhibit cell growth are turned off, leading to the proliferation of organ-destroying cysts. Patients often lose one or both kidneys and are forced to wait for transplant or go on dialysis.
In the study, Crews' team found that triptolide prevented cyst formation in mice. "If we were able to slow the rate of cyst formation by even 10 percent a year, compounded annually, patients would not die from this disease," he said in a statement. "A relatively small effect would have an enormous clinical benefit."
The findings were scheduled to be presented Sunday at the Experimental Biology 2007 meeting in Washington, D.C.