Morphometric and ultrastructural analysis of human granulosa cells after gonadotrophin-releasing hormone agonist or antagonist.

Morphological features of granulosa cells can reflect their functional status. The present study was aimed at comparing possible differences in the fine structure of human granulosa cells exposed to gonadotrophin-releasing hormone (GnRH) agonist or antagonist treatment during ovarian stimulation. Cells were obtained from follicular aspirates of 21 women treated with recombinant follicle-stimulating hormone (rFSH) plus either a GnRH agonist or a GnRH antagonist. Conventional light microscopy procedures and computerized image analysis systems were used to identify different cell type morphological patterns and to quantify different cells distribution. Two morphologically distinct granulosa cell populations, defined as large/pale and small/dark cells, were identified and a different distribution in the two groups of women under investigation was found: a significantly higher percentage in large/pale cells was detected in the agonist-treated women (P<0.05), whereas the percentage of small/dark cells was significantly higher in the antagonist-treated group (P<0.05). Ultrastructural observations showed the presence in both cell populations of typical hallmarks of steroidogenic cells, highlighting signs of functional activity in the large/pale cell population. Further investigations are needed to define the possible clinical significance of these morphological findings.

Effects of the aromatase inhibitor letrozole on in utero development in rats.

BACKGROUND: The aromatase inhibitor letrozole has recently been identified as a promising ovulation-inducing agent. As information regarding possible adverse effects on gestation outcome is limited, the present study was undertaken to evaluate the developmental toxicity potential of letrozole in the rat. METHODS: Pregnant Sprague-Dawley rats were exposed via drinking water to letrozole at 0 (control group), 0.01, 0.02, or 0.04 mg/kg during the period of organogenesis. Developmental endpoints, including intrauterine mortality, fetal growth and incidence of structural abnormalities, were evaluated near the end of gestation. RESULTS: Major treatment-related effects included: (i) a dose-dependent increase in post-implantation loss, which reached 47.2% following exposure to 0.04 mg/kg letrozole; (ii) minor vertebral anomalies affecting 32.2, 29.3 and 42.2% of fetuses exposed to 0.01, 0.02 and 0.04 mg/kg, respectively. CONCLUSION: Gestational exposure to doses of letrozole that are equal to or lower than the daily recommended human dose has toxic effects on prenatal development in rats.

Influence of cigarette smoking on vitamin E, vitamin A, beta-carotene and lycopene concentrations in human pre-ovulatory follicular fluid.

Increasing evidence suggests that fat soluble vitamins and micronutrients have the potential for local modulation of follicular development. Cigarette smoking has been associated with accelerated follicular depletion and derangement of reproductive functions. The present study was initiated to investigate the impact of cigarette smoking on follicular and plasma concentrations of vitamin A, vitamin E, lycopene and beta-carotene. Samples were collected from 17 smokers and 43 non-smoking women undergoing assisted reproduction techniques. Assays were carried out by a reverse-phase high-pressure liquid chromatography (HPLC) method. Smokers had significantly (P < 0.05) lower levels of follicular fluid beta-carotene in comparison to non-smokers (0.02 +/- 0.02 vs. 0.09 +/- 0.02, respectively). No other significant influences on follicular and plasma concentrations were noted. Smokers showed a significantly (P < 0.05) lower fertilization rate in comparison to non-smokers, (55.9 % vs. 71.5 % , respectively). It is postulated that follicular depletion of the antioxidant beta-carotene occurs in response to oxidative stress imposed by cigarette smoke.

The soluble guanylate cyclase inhibitor methylene blue evokes preterm delivery and fetal growth restriction in a mouse model.

BACKGROUND: The present study was undertaken to test whether methylene blue a soluble guanylate cyclase inhibitor, can initiate delivery in the mouse. The potential adverse effects of methylene blue on the fetal growth process were also investigated. MATERIALS AND METHODS: ICR (CD-I) mice were injected subcutaneously with Methylene blue at 0 (vehicle), 5, 30, 50, 60 or 85 mg/Kg on gestation days 15.5 and 16 (plug day = gestation day 0). RESULTS: Methylene blue caused the mice to deliver before gestation day 18 (term gestation). This response was observed in 45%, 50% and 83% of animals receiving Methylene blue at 50, 60 or 85 mg/Kg, respectively (p < 0.05 vs. controls). In a dose-dependent fashion, Methylene blue induced a statistically significant (p < 0.05) derangement of the fetal growth process. CONCLUSION: The present study provides the first evidence that exposure to Methylene blue during late gestation induces preterm delivery and fetal growth restriction. These findings seem to favour the idea that soluble guanylate cyclase and its catalytic product play a role in the control of myometrial contractility and fetal growth process.

Inhibition of nitric oxide synthesis causes preterm delivery in the mouse.

The aim of the present study was to investigate whether an inhibitor of nitric oxide (NO) synthesis provokes preterm delivery in a mouse model. ICR (CD-1) mice were injected s.c. with N(G)-nitro-L-arginine methyl esther (L-NAME) at 0, 40, 70 or 100 mg/kg on gestation day (GD) 15.5 and 16. Delivery was considered preterm if it occurred before GD 18. In a satellite study, the potential ability of the NO donor sodium nitroprusside (SNP) to prevent L-NAME-induced preterm delivery was tested. Five hours before the initiation of treatment regimen with L-NAME at 70 mg/kg, mice were implanted s.c. with micro-osmotic pumps infusing SNP at 0 or 10 microg/kg/min continuously for 3 days. Administration of L-NAME evoked preterm delivery. This response was noted in 64 and 60% of animals treated with 70 and 100 mg/kg L-NAME respectively (P < 0.05 versus control value). Infusion with SNP provided complete and significant (P < 0. 05 versus positive control value) protection from L-NAME-initiated preterm delivery. This is the first report to reveal that an inhibitor of NO synthesis initiates preterm delivery in a mouse model.

Teratological interaction between the bis-triazole antifungal agent fluconazole and the anticonvulsant drug phenytoin.

Previous studies implicated the cytochrome P450 (CYP) system as critical in the teratogenic bioactivation of phenytoin (PHT). Fluconazole (FCZ) is an antifungal bis-triazole with potent inhibitory effect on the principal CYP-dependent metabolic pathway of PHT. In this study an in vivo experimental model was used to evaluate the potential ability of FCZ (2, 10, or 50 mg/kg intraperitoneally) to modulate PHT (65 mg/kg intraperitoneally) teratogenesis on day 12 (plug day = day 1) Swiss mice. PHT alone elicited embryocidal and malformative effects, with cleft palate as the major malformation. Pretreatment with the nonembryotoxic dosage of 10 mg FCZ/kg potentiated PHT-induced teratogenesis, as indicated by a twofold (from 6.2% to 13.3%) increment of cleft palate incidence (P < 0.05). Combined treatment with 50 mg FCZ/kg plus PHT resulted in a statistically significant (P < 0.05) increment of the resorption incidence recorded after PHT-alone exposure, but possibly as a consequence of the increased embryolethality, in the loss of the potentiative effect on PHT teratogenesis. Although the mechanistic nature of teratological interaction between FCZ and PHT remains to be established, these results may not support CYP system-mediated metabolic conversion as the mechanistic component of PHT teratogenesis.

[Preliminary results of an epidemiological survey for diabetes]. / Risultati preliminari di una indagine epidemiologica per il diabete

Mass screening for diabetes in a factory employing 464 subjects by means of a 75 g oral glucose tolerance test and measurement of blood sugar with Dextrosix reagent strips read on a reflectance meter is reported. Values of 120 mg% or over were noted in 10.34% and values in the range 110 to 120 mg% in 7.76%.