The role of Fas in the apoptosis of testicular germ cells was investigated in BALB/c mice and Fas-deficient lpr/lpr mice. Spontaneous apoptosis of germ cells was observed in the testes of 40-day-old BALB/c mice, and experimentally induced cryptorchidism increased this apoptosis to such an extent that there was a decrease in the weight of the testis. Flow cytometry and immunohistochemistry using a Fas-specific monoclonal antibody demonstrated expression of Fas on germ cells including spermatogonia, spermatocytes, and spermatids. Furthermore, analysis by flow cytometry suggested that Fas expression on germ cells was increased following cryptorchidism. However, spontaneous and cryptorchidism-induced apoptosis of germ cells were also observed in 40-day-old Fas-deficient lpr/lpr mice. Moreover, testis weight also decreased following cryptorchidism in the mutant mice. The present results may indicate that the expression of Fas on germ cells does not correlate with spontaneous apoptosis or apoptosis induced by cryptorchidism. However, on the contrary, this study shows that Fas are partly involved in cryptorchidism-induced apoptosis, because the decrease in testis weight of lpr/lpr mice was less than that in BALB/c mice.

Aims/IntroductionTo compare pregnancy outcomes between women with gestational diabetes mellitus (GDM) diagnosed early and late in pregnancy in Japan.Materials and MethodsWe examined women diagnosed with GDM in this multi‐institutional retrospective study. Women were divided into two groups by gestational age at diagnosis: <24 weeks of gestation (early group, 14.4 ± 4.2 weeks) and ≥24 weeks of gestation (late group, 29.6 ± 3.4 weeks). Dietary counseling with self‐monitoring of blood glucose with or without insulin therapy was initiated for both groups. Pregnancy outcomes were compared between the groups.ResultsData from 600 early and 881 late group participants from 40 institutions were included. Although pre‐pregnancy body mass index was higher in the early group than in the late group, gestational weight gain was lower in the early group. Hypertensive disorders of pregnancy and cesarean section were more prevalent in the early than in the late group (9.3% vs 4.8%, P < 0.001; 34.2% vs 32.0%, P < 0.001, respectively). The prevalence of large‐for‐gestational‐age infants was higher in the late than in the early group (24.6% vs 19.7%, respectively, P = 0.025). There was no significant difference in other neonatal adverse outcomes between the groups. Multiple logistic regression analysis showed that early group, nulliparity and pre‐pregnancy body mass index were associated with hypertensive disorders of pregnancy.ConclusionsThese results suggest that maternal complications, including hypertensive disorders of pregnancy and cesarean delivery, were higher in the early group than in the late group. Earlier intervention for GDM might be associated with a reduction in large‐for‐gestational‐age infants.

Aims/Introduction Low birthweight is reportedly associated with type 2 diabetes mellitus; however, this association has not been confirmed in the Japanese population, and whether high birthweight is associated with type 2 diabetes mellitus is controversial. We aimed to investigate the association between birthweight and type 2 diabetes mellitus among a general Japanese population. Materials and Methods Overall 1,135 middle‐ to old‐aged Japanese men and women were enrolled in the Toon Health Study. A 75‐g oral glucose tolerance test was used to diagnose type 2 diabetes mellitus, and a questionnaire survey about birthweight was administered. The association between birthweight and the prevalence of type 2 diabetes mellitus in later life of the participants was examined using multivariable logistic regression analysis. Stratified analysis by current body mass index was also carried out. Results The mean age was 56.5 ± 12.2 years. Type 2 diabetes mellitus was observed in 9.3% of the participants in this study. Compared with the reference group (2,500–3,999 g), the adjusted odds ratio of the low‐birthweight group (<2,500 g) for type 2 diabetes mellitus was 2.46 (95% confidence interval 1.48–4.10). The association between the high‐birthweight group (≥4000 g) and type 2 diabetes mellitus was not significant after including family history of diabetes in the multivariable model. The odds ratio of the low‐birthweight group for type 2 diabetes mellitus was higher in the overweight/obese group than in the non‐overweight group. Conclusions Low birthweight was associated with an increased risk of type 2 diabetes mellitus in a Japanese population, especially in overweight/obese individuals.

In the testis, several types of heat shock proteins (HSPs) have been identified and characterized, although the cellular basis of the HSPs remains elusive. In the present study, alterations in the cellular localization of HSPs, including HSP 25, 60, 70, and 90, were studied during the developing and degenerating periods in the rat testis using immunohistochemistry and Western blotting. HSP25 was expressed in neither germ cells nor somatic cells on all days examined. In contrast, HSP 60 was expressed in Leydig cells during neonatal and prepuberty periods, and only in spermatogonia and primary spermatocytes after puberty. HSPs 70 and 90 were expressed in germ cells, Sertoli cells, and Leydig cells during neonatal and early developing testes, and in spermatocytes and round spermatids after puberty. Besides, there was faint expression of HSP 90 protein in spermatogonia in this period. In the degenerative condition, all HSP proteins were markedly expressed in germ cells after surgery. It would appear that HSPs play roles in unique homeostasis in testes.

We investigated the possible role of dopamine receptors in the mediation of copulatory disorder induced by defeat experience in male mice, using L-dopa and apomorphine. To generate the copulatory disorder, male mice were attacked 20 times daily for 5 consecutive days, as intruders in confrontation with an aggressive resident. Following the repeated exposure to defeat, virtually all intruder males failed to display copulatory behavior towards estrous females. Acute injection of apomorphine (25, 50, 75 micrograms/kg, s.c.) significantly increased both the incidence and the frequency of copulatory elements (mounting and intromission) in a dose-dependent manner. The combination of L-dopa with carbidopa, a dopa decarboxylase inhibitor, also increased significantly copulatory behavior, revealing an inverted U-shaped dose-effect curve. In both cases, locomotion and digging frequencies were significantly decreased. This evidence suggests that dopaminergic mechanisms are involved in the mediation of social stress-induced copulatory disorder.