Studies of the geographic variation of colon and rectal (colorectal) cancer mortality rates in the U.S. have long indicated that they are primariliy linked to solar ultraviolet-B (UVB) radiation: the more UVB in summer, the lower the mortality rate.
The hypothesis to explain this result is that UVB radiation produces vitamin D in the skin, and vitamin D acts to reduce the risk of colorectal and over a dozen other types of cancer. One major study found that intake of 150 IU/day of vitamin D was associated with a reduction by half in incidence of colon cancer, a result that was statistically significant. However, some studies that have investigated the link between dietary sources of vitamin D and colorectal cancer have found a smaller degree of risk reduction comparing the highest versus lowest levels of dietary vitamin D.
In a review of the literature published in the current issue of Nutrition and Cancer, Drs. William Grant and Cedric Garland report that the reason for the sometimes weak link between dietary sources of vitamin D and colorectal cancer incidence or mortality rates is that dietary sources often cannot supply enough vitamin D to be effective in quantities ordinarily consumed. In most such studies, the highest quartile or quintile of those studied consumed over 150-370 I.U./day from dietary sources. That was sufficient in some cases to provide a 10-50% reduction in colorectal cancer risk, but not always at a statistically significant level. However, studies that considered vitamin D intake from both diet and supplements for which the highest levels were over 500 I.U./day found 30-60% risk reduction for the highest versus lowest levels, and the results were uniformly tatistically significant.
NIH scientists describe potential antibody treatment for multidrug-resistant K. pneumoniae
14.03.2018 | NIH/National Institute of Allergy and Infectious Diseases
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Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...
On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...
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At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.
When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...
At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.
Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...
16.03.2018 | Event News
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16.03.2018 | Life Sciences