2.A convenient and stereoselective synthesis of (Z)-allyl selenides via Sm/TMSCl system-promoted coupling of Baylis-Hillman adducts with diselenides.
Yun-kui LIU ; Dan-qian XU ; Zhen-yuan XU ; Yong-min ZHANG
Journal of Zhejiang University. Science. B 2006;7(5):393-396
A simple and convenient procedure for stereoselective synthesis of (Z)-allyl selenides has been developed by a one-pot reaction of diselenides with Baylis-Hillman adducts in the presence of samarium metal-trimethylsilyl chloride under mild conditions. Presumably, the diselenides are cleaved by Sm/TMSCl system to form selenide anions, which then undergo S(N)2' substitution of Baylis-Hillman adducts to produce the (Z)-allyl selenides.
Magnetic Resonance Spectroscopy
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Molecular Structure
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Organoselenium Compounds
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chemistry
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Selenium Compounds
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chemical synthesis
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chemistry
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Stereoisomerism
3.The breeding and culture condition optimization of a high-biomass, selenium-enriched yeast strain.
Xiu-Ying FAN ; Xue-Na GUO ; Xiu-Hui FU ; Xiu-Ping HE ; Chang-Lu WANG ; Bo-Run ZHANG
Chinese Journal of Biotechnology 2003;19(6):720-724
The yeast fusant ZFF-28, which is high in biomass production and rich in selenium, was constructed after mutagenesis and protoplasts fusion between yeast strains. The total selenium content of ZFF-28 is 1.8 and 1.0 times higher than that of the parental strains Saccharomyces cerevisiae ZY-67 and Saccharomyces kluyveri SZY-198 respectively. Using single factor tests and a L16(4(3) x 2(1)) orthogonal design, the cultivation conditions was optimized as: 50mL culture in 250mL shake flasks in molasses containing 6% sugar and 60microg/mL Se at 28 degree C for 25h at 220 r/min, with the initial pH adjusted to 6.0 - 6.5. Under the optimized conditions, the biomass (dry weight) reached 8.2g/L and the Se content of the cells reached 2050microg/g, with organic and inorganic Se contents being 91% and 9% respectively.
Biomass
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Hydrogen-Ion Concentration
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Saccharomyces
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genetics
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growth & development
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metabolism
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Saccharomyces cerevisiae
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genetics
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metabolism
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Selenium
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metabolism
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Selenium Compounds
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metabolism
4.Effects of selenium and B-27 supplements on viability and differentiation of neural stem cell in newborn rat.
Dong-ping TIAN ; Min SU ; Xian-ying WU ; Ge ZHANG
Chinese Journal of Preventive Medicine 2005;39(5):324-327
OBJECTIVETo assess how trace element selenium and B27 supplements affect the neural stem cell (NSc) differentiation in vitro.
METHODSThe development and differentiation of NSc from the newborn rat were observed with primary culture and subculture during treating by sodium-selenite, and selenium-methyl-cysteine (SMC). The immunocytochemistry techniques were used to identify the NSc and mature protein expression with neuron marker beta-tubulin, astrocyte marker GFAP, and oligodendrocyte marker CNPase. The neurosphere morphology and neurite outgrowth were observed.
RESULTSAdding the complete B-27 serum-free supplement, Selenium could promote the neurosphere viability, development and differentiation. Without selenium and B-27, neurosphere could not survive and differentiate. Without B-27 in the medium but there containing selenium, the neurosphere could promote the viability and development into neuron, astrocyte and oligodendrocyte, as compared with the no-containing B-27 and selenium groups, these differentiated cells might have more quantity, more branches and better morphological nerve net. The count of the neuron, astrocyte and oligodendrocyte was 11.2/Hp, 16.1/Hp and 9.3/Hp.
CONCLUSIONSThe selenium should be very important for neural stem cells' survival. Selenium could promote the neurosphere cells differentiation and development.
Animals ; Animals, Newborn ; Cell Differentiation ; drug effects ; Cell Survival ; drug effects ; Cells, Cultured ; Culture Media, Serum-Free ; pharmacology ; Cysteine ; analogs & derivatives ; pharmacology ; Female ; Glial Fibrillary Acidic Protein ; metabolism ; Immunohistochemistry ; Male ; Neurons ; cytology ; drug effects ; metabolism ; Organoselenium Compounds ; pharmacology ; Rats ; Rats, Wistar ; Selenium ; pharmacology ; Selenocysteine ; analogs & derivatives ; Sodium Selenite ; pharmacology ; Stem Cells ; cytology ; drug effects ; metabolism ; Tubulin ; metabolism
5.A Study of Protective Effect of Selenium Against Cytotoxicity of Methylmercury Chloride.
Dai Ha KOH ; Jung Ho YOUM ; Young Sang KOH ; Sun Hwan JOH ; Tak Soon OH
Korean Journal of Occupational and Environmental Medicine 1998;10(3):310-319
The purpose of the present study was to elucidate the cytotoxical influence of mercurial compounds and the protective effect of selenium against mercurial compounds. The effects of mercury compounds and selenium on the syntheses of nitrite(NO2-) and ATP were observed in the cell cultures of EMT-6 cells and peritoneal macrophages from Balb/c mouse. The viabilities of EMT-6 cells and peritoneal macrophages at the end of culture were significantly decreased in dose-dependent manner by methylmercury chloride (CH3HgCl) added into the media. NO2- and ATP syntheses of the cells were dose-dependently inhibited by CH3HgCl. Simultaneous addition of the equimolar dose of selenium completely prevented mercury-induced inhibitions of NO2- and ATP syntheses, which were observed in both of EMT-6 cells and peritoneal macrophages. But these effects of selenium were not appeared in the new medium containing mercurials only which were removed the selenium after the pretreatment of selenium for 6 hours. These results suggest that protective effect of selenium against mercurial compounds was archived by the formation of a complex consisting of Se-Hg or Se-Hg-protein. Though its mechanism was not clear, the protective role of selemium against the mercury toxicity would be exhibited in the immunological system.
Adenosine Triphosphate
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Animals
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Cell Culture Techniques
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Macrophages, Peritoneal
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Mercury Compounds
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Mice
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Nitric Oxide
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Selenium*
6.Determination of hydrogen selenide in workplace air with atomic fluorescence.
Wen-hua QIN ; Yan-yan LU ; Qi GENG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2012;30(2):144-145
OBJECTIVETo determined hydrogen selenide in workplace air with atomic fluorescence.
METHODHydrogen selenide were sampled with 0.1 mol/L sodium hydroxide solution in multi-hole absorbing tubes. The sampled absorbing solution were digested with (9+1) nitric acid/perchloric acid. The selenide in sample were reduced by potassium borohydride in 5.0% hydrochloride solution and determined with atomic fluorescence.
RESULTSThere was a good linearity (r=0.9999) over the concentration of 0-150 microg/L, The precision of low, middle and high concentration were 3.1%, 7.4% and 6.7%, respectively. The sample collection rate can reach 99%.
CONCLUSIONThe method was accurate and sensitive to detect hydrogen selenide in workplace air.
Air Pollutants, Occupational ; analysis ; Selenium Compounds ; analysis ; Spectrometry, Fluorescence ; Spectrophotometry, Atomic ; Workplace
8.Interaction between Inorganic Mercury and Selenium on Tissue Sulfhydryl Groups and Glutathione-linked Enzymes in Rats.
Yonsei Medical Journal 1981;22(2):122-126
The effect of selenium on the tissue sulfhydryl group content and lipid peroxide-destorying enzyme system in the liver, kidney and testis of rat treated with mercury was investigated. The male rats were injected s.c. with HgCl2 (10 micromoles/kg BW) and orally received Na2SeO3 (13 micromoles/kg BW) simultaneously. After 3 days, liver, kidney and testis were removed and analyzed. Mercury decreased the total sulfhydryl group content in the kidney by 25% and the total glutathione content in the kidney and testis by 50% and 36%, respectively, with no changes in other tissues. There was 12% increase in the total sulfhydryl group but not in the total glutathione content in kidney by a simul-taneous treatment of Se and Hg. Glutathione peroxidase (GSH-Px) activities were decreased by 63% in the liver and 69% in the kidney, and glutathione reductase (GSH-Rd) activity was increased in the tests by 16% by the Hg treatment with no changes in Other tissues. Hg had no effect upon glutathione-S-transferase activities in all organs examined. Simultaneous Se treatment increased GSH-Rd activity in the kidney by 23% and GSH-Px activities in liver and kidney by 24% and 21%, respectively, compared to the Hg-treated group. These data indicate that the alleviation of Hg toxicity by Se treatment is well correlated with the protein sulfhydryl group content and GSH-Px activity.
Animal
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Glutathione/metabolism*
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Glutathione Peroxidase/analysis
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Glutathione Reductase/analysis
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Male
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Mercury/toxicity*
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Rats
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Selenium/pharmacology*
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Sulfhydryl Compounds/analysis*
9.An intervention study to prevent gastric cancer by micro-selenium and large dose of allitridum.
Hao LI ; Hui-qing LI ; Yun WANG ; Hai-xiu XU ; Wan-teng FAN ; Mei-ling WANG ; Pei-Hong SUN ; Xiao-yan XIE
Chinese Medical Journal 2004;117(8):1155-1160
BACKGROUNDPeople have more and more concerned about allitridum as studies have shown that taking more raw garlic associated with a lower risk for cancers of the alimentary system. In the present study, we tried to examine whether a large dose of allitridum and a microdose of selenium prevent gastric cancer.
METHODSA double-blind intervention study was performed on the participants aged (35 - 74) years, who had matched at least one of the following criteria: (1) a medical history of stomach disorder, (2) a family history of tumour, or (3) smoking and/or alcohol consumption. A total of 2,526 and 2,507 persons were randomly enrolled into intervention group and control group respectively from 288 natural villages of seven communities in Qixia County, Shandong Province, China. Each person of the intervention group orally took 200 mg synthetic allitridum every day and 100 microg selenium every other day for one month of each year during November 1989 to December 1991. At the same time, people in control group were given 2 placebo capsules containing corn oid with the identical appearance to that in the intervention group.
RESULTSFor all subjects the large dose of allitridum was accepted and no harmful side effects were found during the study. In the first follow-up five years (1992 - 1997) after stopping the intervention, the morbidity rates of malignant tumours in the intervention group declined by 22%, in contrast to the control group, declined by 47.3%. After adjusting for age, gender, and other potential confounders, relative risks (RRs) for all tumours and gastric cancer of the whole population were 0.67 (95% CL: 0.43 - 1.03) and 0.48 (95% CL: 0.21 - 1.06), respectively, and for male group they were 0.51 (95% CL: 0.30 - 0.85) and 0.36 (95% CL: 0.14 - 0.92), respectively. No signigicantly protective effect was found for the female subgroup.
CONCLUSIONThe present study proves that large doses of allitridum and microdorse of selenium may effectively prevent gastric cancer, especially in men.
Adult ; Aged ; Allyl Compounds ; administration & dosage ; Double-Blind Method ; Female ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; Selenium ; administration & dosage ; Stomach Neoplasms ; prevention & control ; Sulfides ; administration & dosage
10.Inflammatory tinea capitis: non-healing plaque on the occiput of a 4-year-old child.
Chia Chun ANG ; Yong Kwang TAY
Annals of the Academy of Medicine, Singapore 2010;39(5):412-414
INTRODUCTIONInflammatory tinea capitis is an uncommon condition in Singapore. In this case report we present a patient whom we managed for this condition.
CLINICAL PICTUREA 4-year-old girl presented to us with multiple pustules over the occipital scalp for 6 weeks, associated with painful cervical lymphadenopathy. Her condition did not respond to topical and oral antibiotics.
TREATMENTThe patient was diagnosed with kerion (inflammatory tinea capitis) and fungal culture of plucked hairs from the kerion grew Microsporum species of dermatophyte. She was treated with a course of oral griseofulvin and topical selenium sulfide shampoo. She was advised to bring her pet cats to the veterinarian for screening, as well as not to share combs with her other siblings.
OUTCOMEHer condition improved with the antifungal therapy, and there was no residual alopecia.
CONCLUSIONPhysicians should consider tinea capitis when they encounter a patient with scalp folliculitis or scarring alopecia in the appropriate clinical context.
Administration, Oral ; Administration, Topical ; Antifungal Agents ; administration & dosage ; Child, Preschool ; Female ; Griseofulvin ; administration & dosage ; Humans ; Microsporum ; isolation & purification ; Selenium Compounds ; administration & dosage ; Tinea Capitis ; drug therapy ; microbiology