Aim: To study the anti-spermatogenic mechanism of supra-physiological doses of testosterone undecanoate (TU).Methods: Twenty fertile adult men received four intramuscular injections of TU at monthly intervals, 1000 mg...Aim: To study the anti-spermatogenic mechanism of supra-physiological doses of testosterone undecanoate (TU).Methods: Twenty fertile adult men received four intramuscular injections of TU at monthly intervals, 1000 mg uponadmission and 500 mg for the subsequent injections. The apoptotic germ cells in the semen were studied under light mi-croscope with tenninal deoxynucleotidyl tmnsferase-mediated dUTP-biotin nick end labeling (TUNEL) and Wright-Giem-sa staining methods. Results: After treatment, the sperm density and the number of spermatogenic cells in the semenwere significantly decreased ( P < 0.01), while the apoptotic ratios of spermatocytes and spermatids increased significantly( P <0.01) as compared with the pretreatment levels. Apoptosis was found to be augmented in the whole series of castoffspennatogenic cells. Conclusion: Besides its suppressive effect on spermatogenesis through a negative feed-backmechanism, TU enhances apoptosis of spermatogenic cells, which may be an additional mechanism of its anti-spermato-genic activity. ( Asian J Androl 1999 Sep; 1: 155 - 158)展开更多
Objective To investigate possible causes resulting in the differences in the spermatogenesis suppression on individual treated with levonorgestrel (LNG) implants and testosterone undecanoate (TU) injectableMethods Tot...Objective To investigate possible causes resulting in the differences in the spermatogenesis suppression on individual treated with levonorgestrel (LNG) implants and testosterone undecanoate (TU) injectableMethods Totally 21 Chinese male volunteers were given treatment with LNG implants (four rods, 75 mg/rod) and intramuscular injection of TU (500 mg,bimonthly for 3 times). According to the effects of treatment, they were divided into two groups, namely, azoospermia group (group A) and oligozoospermia group (group O). Then seminal FSH, LH, T and estradiol (E2) were determined by immunoenzymetric assay, while seminal and serum dihydrotachysterol (DHT) and serum sex hormone binding globulin (SHBG) were by radioimmunoassay, and seminal transferrin (Tf) by scatter turbidimetry assay.Results Seminal FSH, LH and serum DHT, SHBG, FTI (T/SHBG ×100) levels were significantly lower in group A than in group O, while higher seminal concentrations ofE2 were observed in azoospermia group.Conclusion The differences in the spermatogenic suppression in Chinese men might be attributed to different rate of peripheral androgen metabolism, variations in serum SHBG levels, 5á-reductase activity and individual aromatase activity during LNG plus TU administration. In addition, seminal sex hormones might be more sensitive indexes to assess the extent of feedback inhibition on hypothalamus-pituitary-testis with exogenous testosterone plus progestogen in the efficacy hormone male contraceptive trials.展开更多
Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights o...Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G.展开更多
文摘Aim: To study the anti-spermatogenic mechanism of supra-physiological doses of testosterone undecanoate (TU).Methods: Twenty fertile adult men received four intramuscular injections of TU at monthly intervals, 1000 mg uponadmission and 500 mg for the subsequent injections. The apoptotic germ cells in the semen were studied under light mi-croscope with tenninal deoxynucleotidyl tmnsferase-mediated dUTP-biotin nick end labeling (TUNEL) and Wright-Giem-sa staining methods. Results: After treatment, the sperm density and the number of spermatogenic cells in the semenwere significantly decreased ( P < 0.01), while the apoptotic ratios of spermatocytes and spermatids increased significantly( P <0.01) as compared with the pretreatment levels. Apoptosis was found to be augmented in the whole series of castoffspennatogenic cells. Conclusion: Besides its suppressive effect on spermatogenesis through a negative feed-backmechanism, TU enhances apoptosis of spermatogenic cells, which may be an additional mechanism of its anti-spermato-genic activity. ( Asian J Androl 1999 Sep; 1: 155 - 158)
文摘Objective To investigate possible causes resulting in the differences in the spermatogenesis suppression on individual treated with levonorgestrel (LNG) implants and testosterone undecanoate (TU) injectableMethods Totally 21 Chinese male volunteers were given treatment with LNG implants (four rods, 75 mg/rod) and intramuscular injection of TU (500 mg,bimonthly for 3 times). According to the effects of treatment, they were divided into two groups, namely, azoospermia group (group A) and oligozoospermia group (group O). Then seminal FSH, LH, T and estradiol (E2) were determined by immunoenzymetric assay, while seminal and serum dihydrotachysterol (DHT) and serum sex hormone binding globulin (SHBG) were by radioimmunoassay, and seminal transferrin (Tf) by scatter turbidimetry assay.Results Seminal FSH, LH and serum DHT, SHBG, FTI (T/SHBG ×100) levels were significantly lower in group A than in group O, while higher seminal concentrations ofE2 were observed in azoospermia group.Conclusion The differences in the spermatogenic suppression in Chinese men might be attributed to different rate of peripheral androgen metabolism, variations in serum SHBG levels, 5á-reductase activity and individual aromatase activity during LNG plus TU administration. In addition, seminal sex hormones might be more sensitive indexes to assess the extent of feedback inhibition on hypothalamus-pituitary-testis with exogenous testosterone plus progestogen in the efficacy hormone male contraceptive trials.
基金sponsored by Natural Science Foundation of Xinjiang Uygur Autonomous Region (No.2022DO1A164)the Joint Research Found (No.U1831109)in Astronomy under cooperative agreement between the National Natural Science Foundation of China (NSFC)and Chinese Academy of Sciences (CAS)the Natural Science Foundation of Shandong Province (No.ZR2020QA048)。
文摘Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G.