Wednesday, June 30, 2010

Sponging up the mess

"Healing powers for one of the world's deadliest diseases may lie within sponges, sea worms and other underwater creatures." Malaria, a blood-parasite transmitted by mosquitoes, kills nearly a million people each year and infects hundreds-of-thousands of humans. The battle against this deadly disease has forced scientists to look in unlikely places for a cure. Now, they're even looking in depths of the sea.

"University of Central Florida scientist Debopam Chakrabarti is analyzing more than 2,500 samples from marine organisms collected off deep sea near Florida's coast. Some of them could hold the key to developing drugs to fight malaria". Nothing has been proven yet, but Chakarabarti is optimistic. "One active sample" that he tested, "derived from a marine sponge, contained the compound Nortopsentin. Because of this compound's initial promise" at combating disease, Chakrabarti has "already filed an application for patent protection." With assistance from two graduate students, Chakrabarti has "conducted preliminary testing of more than 2,500 samples from the Harbor Branch collection. They conducted tests to evaluate growth inhibitory properties of these samples for malaria parasite growing inside human red blood cells in culture."

Chakrabarti's approach of looking to marine sources for disease treatment is not new. He follows in the footsteps of modern scientists and ancient medics.

In the meantime, Chakrabarti is concerned how the Gulf of Mexico's oil spill will affect his work. "He's also concerned...that the...oil spill may wipe out species that could hold healing properties for many deadly diseases."

"If we can find two or three good molecules that can be easily synthesized in a lab and that can prevent malaria, I'd be very happy," he said.

University of Central Florida (2010, June 28). Underwater sponges and worms may hold key to cure for malaria. ScienceDaily. Retrieved June 30, 2010, from­ /releases/2010/06/100628124601.htm

Sunday, June 13, 2010

Yellow Fever

“Malaria is one of the most pressing health crises of developing countries: in communities stricken by infection, attendance at work and school drops, and poverty deepens…There is no vaccine for malaria, which sickens almost a quarter of a billion people each year and kills a child every 30 seconds.” Scientists race to change those statistics, exploring various avenues for human vaccination and malaria eradication. Recently, “researchers at The Rockefeller University have genetically transformed the yellow fever vaccine to prime the immune system to fend off the mosquito borne parasites that cause the disease. The researchers found that the modified vaccine, along with a booster, provided mice with immunity to the deadly disease.”

“It has been known since the 1960s that” the sporozoite, one form of the malaria parasite “can wake up the immune system and help to protect against future infection.” Unfortunately, the only known “way to gather sporozoites…is to pluck them one-by-one from the salivary glands of irradiated, malaria-ridden mosquitoes. To provide immunity, the attenuated parasites must then be injected in high doses” or “delivered by the bites of hundreds of mosquitoes”, which is “a labor intensive approach not feasible for large-scale use.”

In an effort to find a better way to achieve the “benefits of sporozoite immunization”, scientists, led by Charles Rice, thought “that fighting infection with infection might be the key. They began experimenting with the attenuated yellow fever strain used in the yellow fever vaccine, known as YF17D, which has been used to successfully vaccinate more than 400 million people since 1937. Previous work in the Rice laboratory and by others had shown that this vaccine strain could be modified to include short sequences from other pathogens, including malaria.”

“Immunization of mice with the YF17D-CSP vaccine led to a measurable jump in immune activity against the malaria protein, but the single shot was not enough to protect the animals from infection with the mouse form of the malaria parasite.” The scientists added a booster shot, and discovered that “vaccination with YF17D-CSP plus the sporozoites protected 100 percent of the animals against infection.”

Stoyanov et al. Immunogenicity and protective efficacy of a recombinant yellow fever vaccine against the murine malarial parasite Plasmodium yoelii. Vaccine, 2010; 28 (29): 4644 DOI: 10.1016/j.vaccine.2010.04.071

Rockefeller University (2010, June 11). Yellow fever vaccine modified to fight malaria. ScienceDaily. Retrieved June 13, 2010, from¬ /releases/2010/06/100611222839.htm

Monday, June 7, 2010

Malaria in Venezuela

Miners, in search of gold and diamonds, fear a plague of malaria. “These workers have long caught the disease by venturing into forests where malaria-carrying mosquitoes live. Their strip-mines destroy patches of forest, leaving behind muddy pools and water contaminated with the mercury they use to separate gold from rock.”

“Malaria cases have doubled in Venezuela so far this year as health officials confront an epidemic in a vast southern region where wildcat gold miners are often infected in remote jungle camps.”

Last year, the country reported 10,758 malaria cases. Already this year, 21,601 cases have been recorded. Most patients “were diagnosed in southern Bolivar state, where government officials say there is an epidemic. The statistics, which are updated weekly and circulated among some health officials, cover the period running from the start of the year through May 22.”

“Public health officials attribute the rise in malaria cases in part to a government-led operation this year in which soldiers have evicted thousands of miners from their illegal strip-mines.”

This government initiative displaced miners, who sought refuge in towns. With them, they brought disease and spread malaria into areas that were previously clean.

Dr. Ana Gineth Morales, who heads the Bolivar state Public Health Institute, expected this surge in malaria cases. “It hasn't taken us by surprise," Morales asserts, reassuring interviewers that her agency had been fully prepared. The Public Health Institute is “efficient in diagnosing, detecting." Despite the increase in cases of malaria, few people have died.

But some critics say the malaria situation appears to be out of control.

"We expect malaria cases will keep increasing," said Dr. Angel Granados, of the Bolivar state Medical Association. Granados cites the recent rain and continual movement of miners as contributing causes. “Public health teams haven't been reaching many remote areas including indigenous communities to detect and treat cases,” Granados said.

Granados reminded officials that, earlier this year, one Yekuana Indian community “reported six deaths — including three children and three adults — that came after they suffered high fevers and appeared to be due to malaria. But he said state health officials ruled out malaria saying the deaths were due to other causes and did not include them in their tally.”

James, Ian. “Malaria epidemic hits southern Venezuela.” Associated Press. 5 June 2010.

Wednesday, June 2, 2010

Cerebral malaria

“Scientists are making strides against cerebral malaria, a fatal form of malaria in children that can ravage the brain and is extremely difficult to treat.” Cerebral malaria causes inflammation in the brain, which leads to “the obstruction of blood vessels” and results in brain damage. “New research points to platelets -- known for their role in blood clotting -- as playing an important role in the disease, stimulating the immune system and turning on molecules that increase inflammation.”

Scientists at the University of Rochester Medical Center conducted this study as “part of an ongoing effort to better understand the origin and development of cerebral malaria, which predominantly affects children under the age of 10 living in malaria-endemic areas, such as sub-Saharan Africa.”

"Malaria is a complex disease and we need to look at it from every possible angle, focusing on both vaccine research and basic research, as we've done in this study," said Craig Morrell, D.V.M., Ph.D., assistant professor within the Aab Cardiovascular Research Institute at the Medical Center and lead author of the study. "Our findings increase our knowledge of cerebral malaria and suggest that targeting platelets may prove to be a viable intervention strategy."

Malaria is responsible for approximately 1 million deaths each year. 250-500 million people are afflicted with malaria annually, yet malaria is treatable. Efforts to eradicate malaria are being made internationally. “While research efforts are mainly focused on vaccine development, new therapies to treat malaria are needed, as the parasite that causes malaria -- Plasmodium falciparum -- is becoming resistant to current treatments.”

Morrell's team studies “the development and progression of cerebral malaria, with the goal finding new ways to intervene and treat the disease.” Malaria occurs when the specific parasite infects red blood cells. These infected “blood cells activate platelets, which secrete a key protein…whose job it is to protect against foreign intruders -- in this case, the malaria parasite -- by turning on pro-inflammatory cells, known as monocytes. Monocytes contribute to the inflammation in the blood vessels that leads to obstructions in the brain.”

This study has shown scientists that “the role of platelets is more complex than they initially thought. Ongoing research will focus on when to intervene and influence the activity of platelets, as timing has been found to make a marked difference in the outcome. Additionally, scientists at Rochester are collaborating with researchers from Johns Hopkins University to look at drugs that are approved for the treatment of other conditions to see if they might be effective in treating cerebral malaria.”


Kalyan Srivastava, David J. Field, Angela Aggrey, Munekazu Yamakuchi, Craig N. Morrell, Pieter H. Reitsma. Platelet Factor 4 Regulation of Monocyte KLF4 in Experimental Cerebral Malaria. PLoS ONE, 2010; 5 (5): e10413 DOI: 10.1371/journal.pone.0010413

University of Rochester Medical Center (2010, June 1). Cerebral malaria: Scientists advance understanding of deadly form of malaria in children. ScienceDaily. Retrieved June 2, 2010, from¬ /releases/2010/06/100601114639.htm

Photo from Davidson College: