The hypothesis that a dietary Supplement of selenium (Se) may reduce cancer risk was tested experimetally in humans. Patients with histories of basal/squarnous cell carcinomas of the skin were assigned randomly in dou...The hypothesis that a dietary Supplement of selenium (Se) may reduce cancer risk was tested experimetally in humans. Patients with histories of basal/squarnous cell carcinomas of the skin were assigned randomly in double-blind fashion to dally oral supplements of either Seenriched yeast (200 μg Se/day), or a low-Se yeast placebo. A total of 1312 patients recruited in 1983-1990 were followed with regular dermatologic examinations through 1993 for a total of 8269 person-years of observation. Skin cancer diagnoses were confirmed histologically.Plasma Se concentration was determined at 6-12 months intervals. All deaths and patient-reported illnesses were recorded; reported cancers were confirmed and documented by consultation with the patient medical care providers. The results indicate that Se did not significantly affect the primary endpoints: incidences of recurrent basal/squarnous cell carcinomas of the skin. However, Setreatment was associated with reductions in several secondary endpoints:total mortality, mortality from all cancers combined, as well as the incidence of all cancers combined, lung cancer, colorectal cancer and prostate cancer. The consistencies of these associations over time, between study clinics and for the leading cancer sltes strongly suggests benefits of Se-supplementation for this cohort of patients, supporting the hypopthesis that supplemental Se can reduce cancer risk. Although Se did no shown protective effects against nonmelanoma skin cancers, the suggested reductions in risks to other frequent cancers demand further evaluation in well controlled cliflical intervention trials展开更多
Selenium （Se） is an essential trace element. Autoimmune thyroid diseases （AITD） are destructive inflammatory or anti-receptor autoimmune diseases characterized by reactivity to self-thyroid antigens. However, the ...Selenium （Se） is an essential trace element. Autoimmune thyroid diseases （AITD） are destructive inflammatory or anti-receptor autoimmune diseases characterized by reactivity to self-thyroid antigens. However, the effects of Se on the cytokines in AITD are still unclear. So we researched the role of Selenium （Se） and Thl/Th2 cytokine productions in the pathogenesis of autoimmune thyroid diseases （AITD）.展开更多
Objective:To determine the effect of oral selenium supplementation and semen collection methods on various post thaw semen quality parameters in Saanen bucks.Methods:Sixteen healthy bucks were divided into two equal g...Objective:To determine the effect of oral selenium supplementation and semen collection methods on various post thaw semen quality parameters in Saanen bucks.Methods:Sixteen healthy bucks were divided into two equal groups(n=8 each).The treatment group received selenium at 10-day intervals for three months.Sperm kinematic parameters,morphological parameters,mitochondrial membrane potential,plasma membrane functionality,and sperm DNA integrity were evaluated weekly pre and post-cryopreservation.Results:The mean percentages of the morphological abnormalities were significantly lower in the selenium-supplemented samples when semen was collected by using artificial vagina method(P<0.05).Proximal droplet defects were significantly lower in the selenium supplementation group when semen was collected by electro-ejaculation(P<0.05).Post-thaw sperm parameters such as total motility and progressive motility were significantly higher when semen was obtained by artificial vagina in the selenium-supplemented bucks compared to the electro-ejaculation and the control groups(P<0.05).The sperm kinematic parameters such as curvilinear velocity,average path velocity,and amplitude of lateral head displacement were significantly higher when semen was collected by artificial vagina in the selenium-treated bucks(P<0.05).The percentages of sperm with intact and functional plasma membrane and functional mitochondria were significantly higher in the selenium-supplemented samples collected with artificial vagina compared to the electro-ejaculation method and the control groups(P<0.05).In vitro fertilizing potential was significantly higher in the selenium-supplemented samples collected with artificial vagina compared to the electro-ejaculation method and the control groups,respectively(P<0.05).Conclusions:Oral supplementation of selenium and artificial vagina semen collection improve post thaw sperm quality parameters of Saanen buck.展开更多
文摘The hypothesis that a dietary Supplement of selenium (Se) may reduce cancer risk was tested experimetally in humans. Patients with histories of basal/squarnous cell carcinomas of the skin were assigned randomly in double-blind fashion to dally oral supplements of either Seenriched yeast (200 μg Se/day), or a low-Se yeast placebo. A total of 1312 patients recruited in 1983-1990 were followed with regular dermatologic examinations through 1993 for a total of 8269 person-years of observation. Skin cancer diagnoses were confirmed histologically.Plasma Se concentration was determined at 6-12 months intervals. All deaths and patient-reported illnesses were recorded; reported cancers were confirmed and documented by consultation with the patient medical care providers. The results indicate that Se did not significantly affect the primary endpoints: incidences of recurrent basal/squarnous cell carcinomas of the skin. However, Setreatment was associated with reductions in several secondary endpoints:total mortality, mortality from all cancers combined, as well as the incidence of all cancers combined, lung cancer, colorectal cancer and prostate cancer. The consistencies of these associations over time, between study clinics and for the leading cancer sltes strongly suggests benefits of Se-supplementation for this cohort of patients, supporting the hypopthesis that supplemental Se can reduce cancer risk. Although Se did no shown protective effects against nonmelanoma skin cancers, the suggested reductions in risks to other frequent cancers demand further evaluation in well controlled cliflical intervention trials
基金supported by three programs from the National Natural Science Foundation of China (NSFC) (The experimental study on the effect of trace elements iodine and selenium on the autoimmune thyroid disease (No.30571564)The cross-sectional investigation on hypothyroidism induced by excess iodine intake and the experimental research on pathogenesy (No.30972465)The change of thyroid pathology and the levels of T3,T4 in SePP1,GPX3 knock out mice (No.30810103004)
文摘Selenium （Se） is an essential trace element. Autoimmune thyroid diseases （AITD） are destructive inflammatory or anti-receptor autoimmune diseases characterized by reactivity to self-thyroid antigens. However, the effects of Se on the cytokines in AITD are still unclear. So we researched the role of Selenium （Se） and Thl/Th2 cytokine productions in the pathogenesis of autoimmune thyroid diseases （AITD）.
文摘Objective:To determine the effect of oral selenium supplementation and semen collection methods on various post thaw semen quality parameters in Saanen bucks.Methods:Sixteen healthy bucks were divided into two equal groups(n=8 each).The treatment group received selenium at 10-day intervals for three months.Sperm kinematic parameters,morphological parameters,mitochondrial membrane potential,plasma membrane functionality,and sperm DNA integrity were evaluated weekly pre and post-cryopreservation.Results:The mean percentages of the morphological abnormalities were significantly lower in the selenium-supplemented samples when semen was collected by using artificial vagina method(P<0.05).Proximal droplet defects were significantly lower in the selenium supplementation group when semen was collected by electro-ejaculation(P<0.05).Post-thaw sperm parameters such as total motility and progressive motility were significantly higher when semen was obtained by artificial vagina in the selenium-supplemented bucks compared to the electro-ejaculation and the control groups(P<0.05).The sperm kinematic parameters such as curvilinear velocity,average path velocity,and amplitude of lateral head displacement were significantly higher when semen was collected by artificial vagina in the selenium-treated bucks(P<0.05).The percentages of sperm with intact and functional plasma membrane and functional mitochondria were significantly higher in the selenium-supplemented samples collected with artificial vagina compared to the electro-ejaculation method and the control groups(P<0.05).In vitro fertilizing potential was significantly higher in the selenium-supplemented samples collected with artificial vagina compared to the electro-ejaculation method and the control groups,respectively(P<0.05).Conclusions:Oral supplementation of selenium and artificial vagina semen collection improve post thaw sperm quality parameters of Saanen buck.
