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A new unsymmetric tetradentate salamo-like chemical sensor H2L for fluorescent recognition of Zn2+ has been designed and synthesized. The sensor can recognize Zn2+ from other metal ions examined with selectivity, anti-interference, reliability and high sensitivity (LOD = 1.89 × 10-6 M) in ethanol/H2O solution. The results of UV-Vis and fluorescent spectra analyses, X-ray crystallographic study and DMol3 simulation and calculation (on Materials Studio) indicate that the chelation-enhanced fluorescence (CHEF) recognition mechanism of the sensor H2L for Zn2+ is of its hindered PET process. The sensor H2L for Zn2+ has excellent fluorescence characteristics and has potential application value in biological and environmental systems.

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<p><b>OBJECTIVE</b>To investigate the correlation between the symptoms and serum levels of androgen in healthy Chinese men aged over 40 years, and to work out a new symptomatic inventory for screening late onset hypogonadism (LOH) in Chinese men.</p><p><b>METHODS</b>An 18-item questionnaire was designed and 637 respondents were collected from Beijing, Shanghai, Xi'an and Chongqing. Serum total testosterone, calculated free testosterone, testosterone secretion index and free testosterone index were measured. An analysis of the correlation between symptoms and androgens was performed.</p><p><b>RESULTS</b>The twelve-item symptoms were significantly correlated to 2 or more of the 4 androgens mentioned above, marking up a new symptomatic inventory for screening LOH, with a 70% sensitivity and 46% specificity.</p><p><b>CONCLUSION</b>The new symptomatic inventory is acceptable for the screening purpose. The relatively low specificity may be related to the individual response to the decline of serum androgens and age-related changes of other hormones, such as GH-IGF-1 axis, DHEA, thyroid hormones, melatonin and leptin.</p>

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<p><b>OBJECTIVE</b>To investigate the effects of tributyltin chloride (TBT) and triphenyltin chloride (TPT) on rat testicular Leydig cells.</p><p><b>METHODS</b>The rat Leydig cells (LC-540) were incubated with 0 to 80 nmol/L TBT and TPT for 24 to approximately 96 h, and then the cell viability was determined by MTT. DNA fragmentation ladder formation of cell apoptosis was examined by agarose electrophoresis. Effects of chelator of intracellular Ca2+ (BAPTA) and the inhibitors of PKA, PKC and TPK on cell apoptosis induced by TBT were observed. Effects of TBT on testosterone production in primary cultured rat Leydig cells treated with or without hCG were detected.</p><p><b>RESULTS</b>TBT and TPT suppressed Leydig cell survival in a time- and dose-dependent manner. The suppressive effects of TBT and TPT on the cell survival was caused by apoptosis which was determined by DNA ladder formation. The apoptotic effect of TBT was possibly mediated by the rise in intracellular Ca2+ because it could be blocked by BAPTA, the chelator of intracellular Ca2+; PKA, PKC and TPK inhibitors did not prevent the apoptotic effects induced by TBT. TBT markedly suppressed testosterone production of primary cultured rat Leydig cells with or without hCG stimulation.</p><p><b>CONCLUSION</b>TBT and TPT induced apoptosis in rat testicular Leydig cells possibly through increasing intracellular Ca2+. TBT reduced the testosterone production of rat Leydig cells.</p>

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<p><b>OBJECTIVE</b>To understand the sex hormone levels in elderly men with chronic heart failure and the relationship between sex hormone levels and heart function.</p><p><b>METHODS</b>One hundred male patients diagnosed chronic heart failure clinically aged from 60 to 87 were selected in this study. All patients' left ventricular ejection fraction were less than 0.45. Four hundred elderly healthy men were studied as control. Blood samples were collected in the morning and TT, FT, DHEAS, SHBG, E(2), LH, FSH were measured. The results were compared with the hormone levels of healthy men with the same mean age.</p><p><b>RESULTS</b>(1) In elderly men with chronic heart failure, the level of DHEAS was decreased with age (P < 0.05). However, the levels of SHBG, LH, FSH were increased with age (P < 0.05, P < 0.01). (2) Compared with healthy men the levels of TT, FT, E(2) and DHEAS were decreased significantly (P < 0.01) and the level of SHBG was significantly increased (P < 0.01). (3) The level of FT was positively correlated with LVEF (r = 0.279, P = 0.034).</p><p><b>CONCLUSION</b>The androgen levels in elderly male patients with chronic heart failure were decreased significantly and the level of FT was negatively correlated with degree of heart failure.</p>

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Cultured human testicular tissues were grouped as follows:control group,group tracted with single dosc of human chorionic gonadotropin(hCG), group treated with double doses of hCG given at three-day-interval and group treated with multiple doses of hCG. The dose of hCG was 20kIU/L,and it was added into the medium and incubated for 24 hours. Testosterone was measured by RIA. The result indicated that all three hCG-treated groups had a testosterone secretion peak at 48-72 hours after the first dose of hCG. After the second hCG treatment given in three days interval the testosterone increased again. but its maximal rise reduced. Multiple doses of hCG given successively inhibited the response of Leydig cells to hCG stimulation.