Rapid photon response is demonstrated for devices made using individual single-crystalline selenium nanobelts. The temperature dependence of the photocurrent has been studied between — 70 to 100 C. The best performance is at temperatures below 40 C. The response time to fluorescent light is as quick as 30 ms once tunes on, and the recovery time is as short as 50 ms when the light is off. This s...

The use of supra-dietary doses of chemical antioxidants has attracted increasing interest as a possible primary and secondary cancer prevention strategy. It is possible that some cancer patients have an inherently impaired capacity to contend with oxidative stress because of genetic or environmental factors. Specifically, higher levels of intracellular antioxidants may protect against chromosom...

BACKGROUND Selenium is an essential trace element found in cereals, wheat, dairy products, meat, and fish. This micronutrient may prevent carcinogenesis through several biochemical pathways; one suggested pathway is enhanced apoptosis. OBJECTIVES The relation between selenium and colorectal adenomas was evaluated because the colorectal adenoma is the established precursor lesion of most color...

The mechanism of selenium secretion by the mammary gland and effects of dietary copper and selenium metabolism on selenium in milk were investigated. Radioactive sodium selective selenite was injected into the jugular vein of lactating goats fed concentrates containing 15 or 115 ppm copper. Blood and milk samples were collected hourly for 8 h and daily for 1 wk. Whole blood, plasma, whole milk,...

Cancer prevention studies suggest that selenium is effective in reducing the incidence of cancers including prostate, colon, and lung cancers. Previous reports showed that selenium inhibits premalignant human breast MCF-10AT1 and MCF10AT3B cell growth in vitro and reduces mammary tumor incidence after exposure to carcinogens in tumor models. Because estrogen is critical to the development and d...

Selenium is essential to human health, and its deficiency is associated with different diseases including liver necrosis. Selenium is protective against viral hepatitis and hepatocellular carcinoma (HCC). The underlying molecular mechanisms of selenium effects are not well known. In this study, in vitro response of HCC-derived cell lines to selenium deficiency is examined alone or in conjunctio...

Selenium is a non-metallic chemical element of great important to human health. Low selenium levels in humans are associated with several pathological conditions and are a common finding in HIV infected individuals. We conducted a review of the literature to assess if selenium deficiency or selenium supplementation could play a role in modifying the clinical course of HIV disease. Several studi...

Selenium is known to be present in the bile of selenium-treated animais. Smith et al. (I) reported that rabbit bile, after acute and subacute poisoning with sodium selenite and selenate (0.5 to 3 mg. of selenium per kilo), contained smaller amounts of selenium (36 to 48 y per cent) after oral treatment than after intravenous treatment (336 y per cent). In studies by Dudley (2), it was found, af...

Selenium is essential to human health, and its deficiency is associated with different diseases including liver necrosis. Selenium is protective against viral hepatitis and hepatocellular carcinoma (HCC). The underlying molecular mechanisms of selenium effects are not well known. In this study, in vitro response of HCC-derived cell lines to selenium deficiency is examined alone or in conjunctio...

SOIL ASSOCIATIONS The selenium content of most soils ranges from 0.1 to 2 parts per million. But in general soil selenium content by itself is not a good measure for the potential for occurrence of selenium deficiency in livestock grazing or consuming forages produced from it. Soil pH has a marked effect on the form of selenium present and its availability to the plant. In alkaline, well-aerate...