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[en] Two androgens (testosterone, 5 α dihydrotestosterone) were measured by radioimmunoassay in the seminal liquid. A statistic comparison of the results has been applied to samples taken from sterile men and classed chiefly according to sperm count. Different groups were explored: normospermia; oligospermia; various azoospermias. No significant differences testosterone were found between the groups. Levels of DHT are lower in oligospermia, and such more in azoospermia. The signification of the results is discussed
[fr]Deux androgenes (testosterone et 5 α dihydrotestosterone) ont ete doses par radioimmunologie dans le liquide seminal humain. Une comparaison statistique des resultats a porte sur des echantillons provenant de consultants pour sterilites, differencies notamment selon le spermogramme. Quatre groupes ont ete explores: normospermie; oligospermie; azoospermie secretoire; azoospermie excretoire. La concentration en testosterone ne varie pas de facon significative d'un groupe a l'autre. Par contre les valeurs dela 5 α DHT accusent une baisse chez les oligospermiques, qui s'accentue chez les azooospermiques. La signification de ces resultats est discutee
[en] A novel flow-injection chemiluminescence method for the determination of DNA at ultra-trace level has been established. In 0.8 M sulfuric acid media, the chemiluminescence of the rhodamine B-cerium (IV) or Ce(IV) system is enhanced by DNA, activated previously by imidazole-HCl buffer solution (pH 7.0). The enhanced intensity of chemiluminescence is in proportion to log DNA concentration 1.0x10-8 to 0.1 μg ml-1 for herring sperm DNA and 2.0x10-6 to 0.2 μg ml-1 for calf thymus DNA with 3σ detection limits of 8.3x10-9 μg ml-1 for herring sperm DNA and 3.5x10-7 μg ml-1 for calf thymus DNA, respectively. The relative standard deviation for 1.0x10-4 μg ml-1 herring sperm DNA was 0.99% and 2.0x10-3 μg ml-1 for calf thymus DNA was 1.1% (n=11). Using the optimized system, DNA contents in six synthetic samples has been determined with recoveries of 99.5-109.0%. The possible mechanism has also been studied in this paper
[en] Interest in the preservation of endangered breeds such as the Blanca Andaluza goat, has increased and some steps should be therefore taken to ensure it. The study was designed to determine the seasonal reproductive pattern of Blanca Andaluza bucks, and whether this affects the quality of their semen and its freezability over the year. Seven bucks were used and their body weight, testicular weight, plasma testosterone concentration and fresh sperm quality determined every week. The collected sperm was cryopreserved and stored; it was then thawed and the same sperm quality variables measured every fortnight. High plasma testosterone concentrations were recorded during the summer and autumn, and low concentrations were recorded during winter and spring (p<0.001). No differences were seen between seasons in terms of the percentage of bucks ejaculating, the percentage of active bucks, or ejaculate volume. However, the sperm concentration, the total number of sperm per ejaculate, and the values for most fresh sperm variables were lower during the winter period (at least p<0.05). After freezing-thawing, the quality of winter-collected sperm was better, in some respects, than that of summer-collected sperm (at least p<0.05). These results reveal that Blanca Andaluza bucks show seasonal reproductive activity in terms of their plasma testosterone concentration, but no clear change in their sexual behaviour between seasons was observed. The values of fresh sperm variables also vary over the year, reaching their lowest during winter. However, after freezing-thawing, winter-collected sperm is of overall better quality than sperm collected during the summer. (Author)
[en] To identify tissue-specific expression gene in testicle of differential scrotal circumference bulls and analyze the function of the specific gene on the development of the bull's scrotum in this study. The DDRT-PCR and Reverse Northern Blot Analysis were used to identify tissue-specific expression genes in bulls with differential scrotal circumference. The experiment was designed sixty 6-month-old crossbreeds (Charolais with indigenous Fuzhou female). These were raised under the same age, cross generation, raising condition and management. When the feeding was over after 6 months, the scrotal circumferences of bulls were measured. Four bulls were selected and classified into two groups, and the difference of scrotal circumference is significant between the two groups (P < 0.01). A group was consisted of two bulls with larger scrotal circumference 26±2.5cm. The control group was two crossbreed bulls with smaller scrotal circumference 17±2.2 cm. When the scrotal circumferences were measured, the bulls were castrated by surgical operations. A piece of tissue (2 by 2 by 2 cm) was removed from the deeper area of the testis and stored in liquid nitrogen. A small section (0.5 by 0.5 by 0.5 cm) was used for total RNA extraction by using the TRIZOL reagent kit (GIBCO/BRL, Bethesda, MA, USA). The RNA was prepared for DDRT-PCR experiments and quantitative real-time PCR. The results were shown that six genes corresponded to genes of known or inferred function; either the bovine gene or the likely human orthologue and three genes or ESTs were unknown. Bos taurus similar to galactosidase, beta 1-like; Bos taurus similar to Kinesin heavy chain isoform 5C; Bos taurus similar to ankyrin repeat domain protein 15 isoform and Bos taurus ebd-P2 pseudogene were founded both highly expressed in bulls which had bigger scrotal circumference by qRT-PCR. Their functions may be involved with sperm maturation in the epididymis, sperm protection and preventing the ascent of microorganisms into the adjacent testes and responsible for converting immature sperm into competent functional cells, and movement of spermatozoa. (author)
[en] Meta-analysis with high-quality studies can provide superior evidence. In this paper, we use meta-analysis to analyze the relationship between cadmium (Cd) content in semen and male infertility, and then objectively evaluate the effect of Cd on sperm quality. The objectives of this study were to update our understanding of infertility and to provide evidence to treat and prevent the infertility. We searched potentially relevant studies that were published from establishing database data to April 2018. Articles came from the databases of CNKI, Wanfang, VIP, PubMed, CMCI, and EMBASE. A total of 11 articles were included. We gathered the mean and variance of the infertility group and the control group to compare the Cd content in two groups. In total, the 11 studies include 1707 subjects, 1093 of which were in the infertility group and 614 of which were in the control group. We can get some information from this meta-analysis: SMD = 0.50 (95% Cl 0.39–0.61), Z = 8.92, P < 0.05; the funnel plot of the meta-analysis shows incomplete symmetry, which may have the publication bias. Therefore, the high content of Cd in semen is a causative factor of infertility. The Cd content in semen can be used as an indicator of sperm quality.
[en] Zearalenone (ZEA), a kind of nonsteroidal mycotoxin with estrogenic effects, can influence animal reproductive capacity through interfering with estrogen signaling pathway. Previous studies have shown exposure to ZEA at high doses (higher than No-Observed Effect Level, NOEL) had a significant impact on mouse sperm quality and pregnant rate, but little is known about the effect of exposure to ZEA at low doses (lower than NOEL) on mouse reproductive capacity. This study evaluated the effects of exposure to low-dose ZEA on mouse spermatogenesis and semen quality. Male mice (CD-1) of 21 days were exposed to ZEA at 20, or 40 μg/kg body weight for 14, 28 or 42 days. After exposure to ZEA for 14 days, the spermatogenic cells in seminiferous tubules were declined dose-independently; however in groups treated by ZEA for 28 days, the spermatogenic cells were declined dose-dependently. Moreover, after treatment for 28 days or 42 days, the DNA double stand break (DSB) in spermatogenic cells were increased in a dose-dependent manner in treated groups. Compared with the control group, the sperm concentration, viability, motility, and hyperactive rate in treated groups were decreased dose-dependently and time-dependently. Meanwhile, deformity and mortality rate of sperm in treated groups were increased remarkably dose-dependently too. In conclusion, low dose ZEA impaired male reproductive capacity especially in spermatogenesis and semen quality of mouse. - Highlights: • Exposure of low dose Zearalenone decrease sperm concentration, viability, motility, and hyperactive rate of male mice. • Exposure of low dose Zearalenone impairs spermatogenesis. • Exposure of low dose Zearalenone leads to DSBs incidence increase in mouse germ cells.
[en] The proper assembly of sperm flagellar proteins is fundamental for sperm motility. The sperm- and spermatid-specific isoform of glyceraldehyde 3-phosphate dehydrogenase, GAPDS, is a flagellar protein indispensable for sperm flagellar movement. To obtain information on the assembly of the glycolytic enzyme into the flagellum, the precise localization of rat GAPDS in the flagellum and the stage of incorporation into the flagellum were examined using a monoclonal antibody. Immunolocalization of rat GAPDS was restricted to the fibrous sheath (FS) in the sperm flagellum, and was predominant in the circumferential ribs rather than the longitudinal columns. Immunoreactivity was first detected in the cytoplasm and flagella of the step-16 spermatids during the final step of FS formation. Together with the expression of other FS proteins, the present results indicate the sequential assembly of FS components, suggesting that the expression and transport of GAPDS is regulated in a coordinated manner during sperm flagellar formation
[en] Serum samples from male buffaloes were radioimmunoassayed for steroid and thyroid hormones to investigate circadian rhythms, the effect of growth and season. An evaluation of RIA of serum testosterone with and without extraction yielded unacceptably low recoveries in unextracted serum samples. Studies on temporal variations during the day revealed three peaks for testosterone, four peaks for cortisol and one peak each for T4 and T3. In growing calves the testosterone levels were low (0.1 ng/mL) up to 15 months of age but exhibited peaks at puberty (0.4 ng/mL) and maturity (0.8 ng/mL). Cortisol, T4 and T3 also exhibited peaks at puberty and maturity. Progesterone and oestradiol remained at basal levels throughout growth and development. Breeding buffalo bulls exhibited significant seasonal variations in testosterone, progesterone and oestradiol but not in T4 and T3. Semen quality and sexual behaviour did not vary between seasons. (author)
[en] The aim of the present study was to evaluate consequences of cigarette smoking on male gametes. In this prospective study, sperm parameters such as sperm density, motility, viability and normal morphology were measured according to the WHO criteria. In addition to these standard parameters, we analysed the degree of DNA fragmentation in spermatozoa using the TUNEL-assay with flow cytometry detection in 57 non-smokers and 51 smokers seeking for infertility counselling. The smoking intoxication was assessed by questionnaire and measured with the CO-Tester[reg]. We show that smokers' spermatozoa have a significantly higher DNA fragmentation than non-smokers (32% versus 25.9%, p < 0.01). In contrast there is no significant difference in conventional parameters between smokers and non-smokers. The degree of sperm DNA fragmentation is not significantly correlated with any of the conventional parameters. These findings suggest that cigarette smoking may have deleterious effects on sperm nuclear quality and that sperm DNA fragmentation can therefore be considered as an independent parameter with diagnostic, prognostic, and strategic value in the treatment of infertility