Reference values of semen parameters for normal fertile men in Shanghai / 中华男科学杂志

<p><b>OBJECTIVE</b>To analyze the distribution characteristics of the main semen parameters of healthy semen donors and normal fertile men in Shanghai, compare the semen quality between the two groups, and investigate the normal reference values of the semen parameters of the fertile population in Shanghai.</p><p><b>METHODS</b>We obtained semen samples from 100 healthy donors and 41 fertile men, performed semen analyses according to the WHO (2010) guidelines, and determined the semen volume, sperm concentration, sperm progressive motility, total sperm count and total progressively motile sperm count. We analyzed the distribution of the semen parameters of the normal fertile men, and obtained the lower limits of their normal reference values.</p><p><b>RESULTS</b>There were no statistically significant differences in the main semen parameters between the healthy donors and normal fertile men (P < 0.05). The lower reference limits for the semen parameters of normal fertile men in Shanghai (P < 0.05) were as follows: sperm concentration > or = 27.3 x 10(6)/ml, sperm progressive motility > or = 8.1%, semen volume > or = 0.82 ml, total sperm count > or = 44.73 x 10(6) per ejaculate, and total progressively motile sperm count > or = 24.68 x 10(6) per ejaculate.</p><p><b>CONCLUSION</b>For the evaluation of male fecundity, total sperm count and total progressively motile sperm count may be two better predictors than others.</p>

Direct fumigation for freeze-thawing of human sperm: an experimental study / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the effect of direct fumigation on the post-thaw recovery rate of cryopreserved spermatozoa, and to search for a best method for human sperm cryopreservation.</p><p><b>METHODS</b>We collected semen samples from 100 donors conforming to the normal reference values in WHO Laboratory Manual for the Examination and Processing of Human Semen (5th Ed), divided them into two groups, and subjected them to cryopreservation by programmable freezing (Group A) and direct fumigation (Group B), respectively. We detected the progressive motility of pre-freezing and post-thaw sperm with a computer-assisted semen analyzer, and compared the effects of the two methods on the functional integrity of sperm membrane and the rate of abnormal sperm using the percentage of hypo-osmotic swelling sperm and modified Papanicolaou staining.</p><p><b>RESULTS</b>Statistically significant differences were found in post-thaw sperm progressive motility between the Groups A and B ([34.0 +/- 18.4]% vs [43.0 +/- 19.5]%, P<0.05), both remarkably decreased as compared with pre-freezing ([57.0 +/- 16.7]%, P<0.05). Such differences were also found in the post-thaw recovery rate of progressively motile sperm between the two groups ([52.2 +/- 20.6]% vs [67.1 +/- 20.0]%, P<0.05). The post-thaw percentage of hypo-osmotic swelling sperm was obviously decreased in both Groups A and B ([67.1 +/- 11.1]% and [70.6 +/- 10.0]%) in comparison with pre-freezing ([84.5 +/- 7.5]%, P<0.05), with significant differences between A and B (P<0.05). However, the rate of sperm abnormality was evidently increased in Groups A and B ([85.0 +/- 8.7% and [85.7 +/- 9.1]%), significantly higher than pre-freezing ([77.8 +/- 9.6]%, P<0.05), but with no significant differences between A and B (P>0.05).</p><p><b>CONCLUSION</b>Direct fumigation is superior to programmable freezing for its easier operation, wider application, and higher sperm recovery rate.</p>

Expression of the retinoic acid-metabolizing enzymes RALDH2 and CYP26b1 during mouse postnatal testis development / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To study the expression pattern of the retinoic acid metabolizing enzymes RALDH2 and CYP26b1 during mouse postnatal testis development at both mRNA and protein levels.</p><p><b>METHODS</b>Real-time polymerase chain reaction and Western blot analysis were performed to determine the relative quantity of RALDH2 and CYP26b1 at both mRNA and protein levels at postnatal day 1, 5, 10, 20, and in adult mice (70 days testes). Testicular localization of RALDH2 and CYP26b1 during mouse postnatal development was examined using immunohistochemistry assay.</p><p><b>RESULTS</b>Aldh1a2 transcripts and its protein RALDH2 began to increase at postnatal day 10, and remained at a high level through postnatal day 20 to adulthood. Cyp26b1 transcripts and CYP26b1 protein did not change significantly during mouse postnatal testis development. RALDH2 was undetectable in the postnatal 1, 5 and 10 day testes using immunohistochemistry assay. At postnatal day 20 it was detected in pachytene spermatocytes. Robust expression of RALDH2 was restricted in round spermatids in the adult mouse testis. In the developing and adult testis, CYP26b1 protein was confined to the peritubular myoepithelial cells.</p><p><b>CONCLUSION</b>Our results indicate that following birth, the level of retinoic acid in the seminiferous tubules might begin to increase at postnatal day 10, and maintain a high level through postnatal day 20 to adulthood.</p>

Estrogens affect Sertoli cells and the blood-testis barrier in pubertal rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the correlation of exogenous estrogens with the expression of FasL in Sertoli cells and the blood-testis barrier during the differentiation and maturation period of Sertoli cells, and to discuss the related factors that influence the blood-testis barrier of pubertal rats.</p><p><b>METHODS</b>Super-physiological doses of exogenous estrogenic compounds (diethylstilbestrol and estradiol) were administered to pubertal Sprague-Dawley rats in vitro and in vivo, the FasL expression in the Sertoli cells of the rats detected by immunohistochemistry and Western blot, and the changes in the blood-testis barrier observed with the electron microscope.</p><p><b>RESULTS</b>After the exposure to exogenous estrogens, the FasL expression was markedly up-regulated in the immature Sertoli cells (P < 0.05) as well as in the Sertoli cell membrane and the blood-testis barrier of the epithelium. The tracer lanthanum passed through the blood-testis barrier and reached the whole layer of the epithelium at 18 days.</p><p><b>CONCLUSION</b>Super-physiological dose of exogenous estrogens can change the expression and distribution of FasL in immature Sertoli cells and affect the structure of the blood-testis barrier.</p>