Bacterial Methylation of Selenium

For several decades, excessive levels of selenium in feeds have been known to cause various toxic symptoms in livestock. Excessive selenium levels in feeds are the result of plants growing on soils which contain significant levels of selenium. The natural cycling process by which selenium becomes available appears to involve various chemical weathering processes. In addition, microbial action may play a direct or indirect role in rendering selenium soluble. (1). The extent to which microoganisms are involved in the natural cycling processes has been subject to considerable discussion. It has been demonstrated that mold can convert selenate or selenite to a volatile substance with a garlic-like odor. The substance has been identified as dimethyl selenide (2). Other workers (3,4) showed that the addition of selenite or selenite to soils resulted in the volatilization or loss of selenium. The volatilization was shown to be due to microbiological action, but the identity of the organisms was not determined. Unpublished work from South Dakota State University has indicated that bacteria might also be involved in the methylation of selenium. Recently, other workers (5) have isolated one coryneform bacterium which can convert inorganic selenium to dimethyl selenide. This is not necessarily surprising since bacteria have been shown to be involved in the methylation of mercury and arsenic (6,7). Since little is known concerning the actual involvement of bacteria in the natural cycling of selenium, this study was undertaken for the following purposes: 1. To isolate and identify soil bacteria which are capable of converting inorganic selenium to volatile compounds. 2. To identify the volatile selenium compounds generated by the isolated bacteria

Survey of digital solution of differential equations

Call number: LD2668 .R4 1966 H99

Genomics and proteomics of immune modulatory effects of a butanol fraction of echinacea purpurea in human dendritic cells

<p>Abstract</p> <p>Background</p> <p><it>Echinacea </it>spp. extracts and the derived phytocompounds have been shown to induce specific immune cell activities and are popularly used as food supplements or nutraceuticals for immuno-modulatory functions. Dendritic cells (DCs), the most potent antigen presenting cells, play an important role in both innate and adaptive immunities. In this study, we investigated the specific and differential gene expression in human immature DCs (iDCs) in response to treatment with a butanol fraction containing defined bioactive phytocompounds extracted from stems and leaves of <it>Echinacea purpurea</it>, that we denoted [BF/S+L/Ep].</p> <p>Results</p> <p>Affymetrix DNA microarray results showed significant up regulation of specific genes for cytokines (IL-8, IL-1β, and IL-18) and chemokines (CXCL 2, CCL 5, and CCL 2) within 4 h after [BF/S+L/Ep] treatment of iDCs. Bioinformatics analysis of genes expressed in [BF/S+L/Ep]-treated DCs revealed a key-signaling network involving a number of immune-modulatory molecules leading to the activation of a downstream molecule, adenylate cyclase 8. Proteomic analysis showed increased expression of antioxidant and cytoskeletal proteins after treatment with [BF/S+L/Ep] and cichoric acid.</p> <p>Conclusion</p> <p>This study provides information on candidate target molecules and molecular signaling mechanisms for future systematic research into the immune-modulatory activities of an important traditional medicinal herb and its derived phytocompounds.</p

Metabolic syndrome in a Taiwanese metropolitan adult population

<p>Abstract</p> <p>Background</p> <p>Metabolic syndrome (MS) is a combination of medical disorders that increase one's risk for cardiovascular disease and diabetes. Little information exists on the prevalence of MS in a general adult population in Taiwan.</p> <p>Methods</p> <p>We did a cross-sectional survey in a representative sample of 2,359 Chinese adults aged 40 years and over who lived in a metropolitan city, Taiwan in 2004–05. MS was defined by Adult Treatment Panel III criteria modified for Asians.</p> <p>Results</p> <p>The prevalence of MetS was 35.32% and 43.23% in men aged 40–64 years and 65 years and over, respectively, and 24.19% and 51.82% in women aged 40–64 years and 65 years and over. Older age, postmenopausal status, higher body mass index, current smoking, low education attainment, low household income, no alcohol consumption, lower level of occupation physical activity, and a family history of diabetes were associated with increased odds of MetS.</p> <p>Conclusion</p> <p>MetS was present in more than 30% of the Taiwan adult population aged 40 years and over in a metropolitan area; there were substantial variations by age and body mass index groups.</p

An Investigation into the Cytotoxic Effects of 13-Acetoxysarcocrassolide from the Soft Coral Sarcophyton crassocaule on Bladder Cancer Cells

Active compounds from natural products have been widely studied. The anti-tumor effects of 13-acetoxysarcocrassolide isolated from Formosan soft coral Sarcophyton crassocaule on bladder cancer cells were examined in this study. An MTT assay showed that 13-acetoxysarcocrassolide was cytotoxic to bladder female transitional cancer (BFTC) cells. We determined that the BFTC cells underwent cell death through apoptosis by flow cytometry. Due to the highly-migratory nature of the BFTC cells, the ability of 13-acetoxysarcocrassolide to stop their migration was assessed by a wound healing assay. To determine which proteins were affected in the BFTC cells upon treatment, a comparative proteomic analysis was performed. By LC-MS/MS analysis, we identified that 19 proteins were up-regulated and eight were down-regulated. Seven of the proteins were confirmed by western blotting analysis. This study reveals clues to the potential mechanism of the cytotoxic effects of 13-acetoxysarcocrassolide on BFTC cells. Moreover, it suggests that PPT1 and hnRNP F could be new biomarkers for bladder cancer. The results of this study are also helpful for the diagnosis, progression monitoring and therapeutic strategies of transitional cell tumors