Experimental Marburg Vaccine Prevents
Disease 2 Days after Infection
|An experimental vaccine developed to prevent outbreaks of Marburg hemorrhagic fever continues to show promise in monkeys as an emergency treatment for accidental
exposures to the virus that causes the disease.
An experimental vaccine developed to prevent
outbreaks of Marburg hemorrhagic fever continues to show promise in monkeys as an emergency treatment for accidental exposures to the virus that causes the disease. There is no licensed treatment for Marburg infection, which has a high fatality rate. In a study of rhesus macaques, 5 of 6 monkeys survived a lethal dose of Marburg virus when treated 24 hours after infection and 2 of 6 survived
when treated 48 hours after infection. Because rhesus macaques typically succumb to Marburg infection faster than humans, the post-exposure treatment window might be extended even further in humans, study authors say.
The study, overseen by a scientific team from NIH and three other groups with expertise in viral hemorrhagic fevers, was posted online June 16 by the journal Emerging Infectious Diseases.
Marburg and Ebola are the only members of the filovirus family. They are hemorrhagic fever pathogens, meaning the infection may lead to shock, bleeding and multi-organ failure. According to the World Health Organization, Marburg hemorrhagic fever has a fatality rate of up to 80 percent, while Ebola fever has a fatality rate of up to 90 percent.
Vitamin D Status Not Associated with Risk for Less Common Cancers
Despite hopes that higher blood levels of vitamin
D might reduce cancer risk, a large study finds no protective effect against non-Hodgkin’s
lymphoma or cancer of the endometrium, esophagus, stomach, kidney, ovary or pancreas.
In this study, conducted by scientists from NCI and many other research institutions, data based on blood samples originally drawn for 10 individual studies were combined to investigate whether people with high levels of vitamin D were less likely to develop these rarer cancers. Details of these analyses appeared as a set of papers in the June 18 online issue of the American
Journal of Epidemiology, and in print in the July issue.
“We did not see lower cancer risk in persons with high vitamin D blood concentrations compared to normal concentrations for any of these cancers,”
said NCI’s Dr. Demetrius Albanes, one of the study investigators. “And, at the other end of the vitamin D spectrum, we did not see higher cancer risk for participants with low levels.”
Vitamin D is made naturally by the body when the skin is exposed to sunlight; it can also be obtained from a few foods in which it occurs naturally,
from fortified foods and from nutritional supplements. Vitamin D is essential for healthy bones, calcium absorption and immune function.
Study Finds Novel Pathway May Open Doors for New Blood Pressure Treatments
Researchers have found that increasing certain proteins in the blood vessels of mice relaxed the vessels, lowering the animals’ blood pressure. The study provides new avenues for research that may lead to new treatments for hypertension.
“The paper demonstrates that cytochrome P450 plays an important role in the management of high blood pressure, a disease of enormous public health concern,” said the paper’s senior author, Dr. Darryl Zeldin of NIEHS. The study was published
online in the FASEB Journal.
Researchers Discover How Folate Promotes Healing in Spinal Cord Injuries
The vitamin folate appears to promote healing
in damaged rat spinal cord tissue by triggering
a change in DNA, according to a laboratory study funded by NIH. Researchers showed that the healing effects of the vitamin increased with the dosage, until regrowth of the damaged tissue
reached a maximum level. After this threshold
was reached, regrowth declined progressively with increasing doses until it reached the level seen in the absence of the vitamin.
Specifically, folate stimulated a process known as DNA methylation, a natural biochemical process in which chemical compounds known as methyl
groups are attached to DNA. The study results suggest that a greater understanding of the chemical sequences associated with folate metabolism
and DNA methylation may lead to new techniques to promote healing of damaged spinal cords and other nervous system injuries. More studies are needed to determine what role folate might play in treating human beings with spinal cord injury. The study was supported by NICHD, NIDDK, NIDCR and NINDS. Findings were published
in the Journal of Clinical Investigation.—