Search results for " gonad"

Pigmentation polymorphism in the invasive amphipod Dikerogammarus villosus : some insights into its maintenance

2004

Dikerogammarus villosus, a freshwater invasive amphipod, exhibits conspicuous pigmentation polymorphism. This polymorphism is documented in two recently colonized areas, the Saand Moselle rivers (north-eastern France), and some of the mechanisms by which pigmentation polymorphism can arise and be maintained are addressed. Body size, reproductive status, fecundity and mate choice are compared among morphs of D. villosus in field samples collected in summer 2001. Body size and female gonad developmental stage were comparable among the different morphs, suggesting that polymorphism is not the result of changes in pigmentation with age or moult- cycle. Fecundity and reproductive status (paired …

Endocrine correlates of the breeding asynchrony between two Corsican populations of Blue tits (Parus caeruleus)

2004

International audience; Analyses of the development of the reproductive system in seasonally breeding birds in the framework of long-term ecological studies are rare. Here, we present the Wrst results of such a study in two Corsican populations of a European passerine bird, the blue tit (Parus caeruleus). The two study populations occupy diVerent oak habitats and are separated by only 25km. Despite their close proximity, they show a one-month diVerence in onset of egg laying, even after controlling for altitude. This micro-geographic diVerence in breeding date appears adaptive because both study populations raise chicks when food is most plentiful. In our study, males reached their maximum …

Apolipoprotein B is regulated by gonadotropins and constitutes a predictive biomarker of IVF outcomes

2016

Background Follicular fluid (FF) is an important micro-environment influencing oocyte growth, its development competence, and embryo viability. The FF content analysis allows to identify new relevant biomarkers, which could be predictive of in vitro fertilization (IVF) outcomes. Inside ovarian follicle, the amount of FF components from granulosa cells (GC) secretion, could be regulated by gonadotropins, which play a major role in follicle development. Methods This prospective study included 61 female undergoing IVF or Intra-cytoplasmic sperm injection (ICSI) procedure. Apolipoprotein B (APOB) concentrations in follicular fluid and APOB gene and protein expression in granulosa cells from rep…

Activation of silent mating type information regulation 2 homolog 1 by human chorionic gonadotropin exerts a therapeutic effect on hepatic injury and…

2017

Incidence and prevalence of inflammatory liver diseases has increased over the last years, but therapeutic options are limited. Pregnancy induces a state of immune tolerance, which can result in spontaneous improvement of clinical symptoms of certain autoimmune diseases including autoimmune hepatitis (AIH). We investigated the immune-suppressive mechanisms of the human pregnancy hormone, chorionic gonadotropin (hCG), in the liver. hCG signaling activates silent mating type information regulation 2 homolog 1 (SIRT1), which deacetylates forkhead box o3 (FOXO3a), leading to repression of proapoptotic gene expression, because the immunosuppressive consequence attributed to the absence of caspas…

Gonadal sexual differentiation of European sea bass (Dicentrarchus labrax, L. 1758) of fingerlings in different size classes

2016

This report describes a study of the gonad differentiation in fingerlings of European sea bass (Dicentrarchus labrax) belonging to different size groups. Fishes were divided into four groups according to their weight: Group 1 (4.5 ± 0.7 g), Group 2 (9.2 ± 0.8 g), Group 3 (14.8 ± 1.8 g), and Group 4 (21.8 ± 2.3 g). In all groups, low percentages of undifferentiated or early sexually differentiated fish were found. Higher percentages of fully differentiated ovaries were found in Groups 1 and 3. Fully differentiated testes occurred in 90% of Group 4. Ninety percent of fish in Group 2 had gonads with intratesticular oocytes. This highlights the occurrence of intersexual cases and suggests that …

Subcutaneous gonadotropin therapy in male patients with hypogonadotropic hypogonadism

1991

Objective The response to subcutaneous (SC) gonadotropin replacement therapy, using human chorionic gonadotropin (hCG) and human menopausal gonadotropin (hMG) or hCG alone, was evaluated in male hypothalamic hypogonadism. Design Sixteen patients with hypothalamic hypogonadism were treated with gonadotropins for induction of puberty and normalization of spermatogenesis. The results were analyzed retrospectively. Setting The study was carried out in a clinical endocrinology department providing tertiary care and in private practices of endocrinology. Patients Eight patients with idiopathic hypogonadotropic hypogonadism and eight patients with Kallmann's syndrome in prepubertal or early pubert…

Elevated serum levels of IGF-binding protein 2 in patients with non-seminomatous germ cell cancer: correlation with tumor markers alpha-fetoprotein a…

2008

Background/aimsAlterations of the IGF system have been described in several different types of cancer. However, no information is available about the role of the IGF system in patients with non-seminomatous germ cell cancer.MethodsFree IGF-I, IGF-II, acid-labile subunit, and IGF-binding proteins (IGFBPs) 1–4 were analyzed by specific RIAs in 32 patients with untreated non-seminomas and compared with IGFBP levels of 38 healthy controls. Serum IGFBPs were analyzed by western ligand blotting (WLB) and immunoblotting. In 16 patients, IGFBP profiles were measured before, during, and after treatment.ResultsIn patients with testicular cancer, IGF-II levels were on average 1.44-fold higher than in …

Tumor Volume, CT Scan, Lymphography, Sonography, Intravenous Pyelography, and Tumor Markers in Testis Tumors

1989

Correlation of tumor volume to tumor stage in 134 patients with nonseminomatous testicular tumors, which were classified according to the TNM system, revealed similar tumor load for N0 and N1 patients. CT scans (n = 92), lymphangiography (n = 47), intravenous pyelography (IVP) (n = 134), sonography (n = 118) and serial tumor markers (n = 82) were evaluated for sensitivity, specificity and accuracy, both separately and in different combinations. The best individual results were obtained by lymphangiography (sensitivity 0.77, specificity 0.73, accuracy 0.75) and CT scan (sensitivity 0.52, specificity 0.91, accuracy 0.70). In combination CT scan and lymphangiography were the most valuable diag…

A case of late diagnosis and management of 46 XY complete gonadal dysgenesis in adulthood

2021

High progesterone levels in women with high ovarian response do not affect clinical outcomes: a retrospective cohort study

2014

Background The potentially detrimental role of progesterone during the follicular phase has been a matter of controversy for several years; however, few studies have analyzed the effects of combined raised estradiol and progesterone levels on pregnancy outcomes. The aim of the present study was to determine the influence of high progesterone levels on clinical outcomes in the context of high ovarian response. Methods We performed a retrospective cohort study that included 2850 women classified as high responders. The women were subdivided into six groups depending on their progesterone concentration on the day of human chorionic gonadotropin (hCG) administration: 1.81 ng/ml (>p90). Ovarian …