452 resultados para infertility


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An endocrine disruptor (ED) is an exogenous compound that interferes with the body's endocrine system. Exposure to EDs may result in adverse health effects such as infertility and cancer. EDs are composed of a vast group of chemicals including compounds of natural origin such as phytoestrogens or mycotoxins and a wide range of man-made chemicals such as pesticides. Synthetic compounds may find their way into the food chain where a number of them can biomagnify. Additionally, processing activities and food contact materials may add further to the already existing pool of food contaminants. Thus, our diet is considered to be one of the main exposure routes to EDs. Some precautionary legislation has already been introduced to control production and/or application of some persistent organic pollutants with ED characteristics. However, newly emerging EDs with bioaccumulative properties have recently been reported to appear at lower tiers of the food chain but have not been monitored at the grander scale. Milk and dairy products are a major component of our diet, thus it is important to monitor them for EDs. However, most methods developed to date are devoted to one group of compounds at a time. The UHPLC-MS/MS method described here has been validated according to EC decision 2002/657/EC and allows simultaneous extraction, detection, quantitation and confirmation of 19 EDs in milk. The method calibration range is between 0.50 and 20.0 μg kg with coefficients of determination above 0.99 for all analytes. Precision varied from 4.7% to 23.4% in repeatability and reproducibility studies. Established CCα and CCβ values (0.11-0.67 μg kg) facilitate fast, reliable, quantitative and confirmatory analysis of sub μg kg levels of a range of EDs in milk.

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While feminist scholarship has centred reproduction in women’s lives, it has inadequately explored its meanings in men’s. If we assume that reproduction happens in relationships of one kind or another between males and females, then missing men is a considerable oversight. Although there is now much research on fatherhood,merely focussing on this end-stage assumes that women take care of all of the foreplay, leaving unanswered questions in relation, inter alia, to men’s desires for parenthood,men’s involvement in planning or lack of planning to have children, the way men struggle or cope with infertility, their encounters with new reproductive technologies and surrogate mothers, their experiences of foetal screening, their involvement in abortion decision-making, and their experiences of becoming or not becoming a father. In this article I argue that men have compelling experiences throughout the reproductive trajectory deserving of more attention. I offer a profeminist theoretical composition for advancing further enquiries on men and reproduction,which begins with the feminism-informed Critical Studies of Men and Masculinities (CSM), and then weaves this together with the theories of intimate citizenship, sociology of the body, and the sociology of science and technology. I will propose how concepts from these collective theories may be useful in opening up layered questions about gender relations, intimacy, bodies, and technologies in future studies of men and reproduction.

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OBJECTIVE: Progesterone (P4) plays a central role in women's health. Synthetic progestins are used clinically in hormone replacement therapy (HRT), oral contraceptives, and for the treatment of endometriosis and infertility. Unfortunately, synthetic progestins are associated with side effects, including cardiovascular disease and breast cancer. Botanical dietary supplements are widely consumed for the alleviation of a variety of gynecological issues, but very few studies have characterized natural compounds in terms of their ability to bind to and activate progesterone receptors (PR). Kaempferol is a flavonoid that functions as a non-steroidal selective progesterone receptor modulator (SPRM) in vitro. This study investigated the molecular and physiological effects of kaempferol in the ovariectomized rat uteri.

METHODS: Since genistein is a phytoestrogen that was previously demonstrated to increase uterine weight and proliferation, the ability of kaempferol to block genistein action in the uterus was investigated. Analyses of proliferation, steroid receptor expression, and induction of well-established PR-regulated targets Areg and Hand2 were completed using histological analysis and qPCR gene induction experiments. In addition, kaempferol in silico binding analysis was completed for PR. The activation of estrogen and androgen receptor signalling was determined in vitro.

RESULTS: Molecular docking analysis confirmed that kaempferol adopts poses that are consistent with occupying the ligand-binding pocket of PRA. Kaempferol induced expression of PR regulated transcriptional targets in the ovariectomized rat uteri, including Hand2 and Areg. Consistent with progesterone-l ke activity, kaempferol attenuated genistein-induced uterine luminal epithelial proliferation without increasing uterine weight. Kaempferol signalled without down regulating PR expression in vitro and in vivo and without activating estrogen and androgen receptors.

CONCLUSION: Taken together, these data suggest that kaempferol is a unique natural PR modulator that activates PR signaling in vitro and in vivo without triggering PR degradation.

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Spermatogenesis is a complex process reliant upon interactions between germ cells (GC) and supporting somatic cells. Testicular Sertoli cells (SC) support GCs during maturation through physical attachment, the provision of nutrients, and protection from immunological attack. This role is facilitated by an active cytoskeleton of parallel microtubule arrays that permit transport of nutrients to GCs, as well as translocation of spermatids through the seminiferous epithelium during maturation. It is well established that chemical perturbation of SC microtubule remodelling leads to premature GC exfoliation demonstrating that microtubule remodelling is an essential component of male fertility, yet the genes responsible for this process remain unknown. Using a random ENU mutagenesis approach, we have identified a novel mouse line displaying male-specific infertility, due to a point mutation in the highly conserved ATPase domain of the novel KATANIN p60-related microtubule severing protein Katanin p60 subunit A-like1 (KATNAL1). We demonstrate that Katnal1 is expressed in testicular Sertoli cells (SC) from 15.5 days post-coitum (dpc) and that, consistent with chemical disruption models, loss of function of KATNAL1 leads to male-specific infertility through disruption of SC microtubule dynamics and premature exfoliation of spermatids from the seminiferous epithelium. The identification of KATNAL1 as an essential regulator of male fertility provides a significant novel entry point into advancing our understanding of how SC microtubule dynamics promotes male fertility. Such information will have resonance both for future treatment of male fertility and the development of non-hormonal male contraceptives.

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A bactéria Campylobacter fetus divide-se em duas subespécies C. fetus fetus (Cff) e C. fetus venerealis (Cfv). Cfv é o agente patogénico responsável pela campilobacteriose genital bovina (CGB), uma doença que provoca infertilidade em vacas. Cff pode provocar abortos esporádicos, mas não provoca CGB. Neste trabalho procedeu-se à pesquisa de C. fetus por imunofluorescência direta (IFD) em 117 amostras prepuciais, recolhidas por raspagem, de touros pertencentes a 25 explorações na região do Alentejo. A prevalência real de CGB na amostra, considerando a sensibilidade e especificidade do teste, foi de 52,89% de animais e 80% de explorações. Foi também realizada uma comparação entre dois testes de diagnóstico de CGB, a IFD e o isolamento bacteriológico. O isolamento bacteriológico foi difícil de executar e a presença de bactérias contaminantes foi bastante problemática, levando a resultados falso-negativos. A sua correlação com a IFD foi muito baixa, tendo esta revelado ser muito mais sensível; #### Abstract Search for Campylobacter fetus in preputial samples of bulls from Alentejo region The bacteria Campylobacter fetus comprises two subspecies, C. fetus fetus (Cff) and C. fetus venerealis (Cfv). Cfv is the pathogen responsible for bovine genital campylobacteriosis (BGC), a disease that causes infertility in cows. Cff may lead to sporadic miscarriages, but does not cause BGC. In this work we searched for C. fetus by direct immunofluorescence (DIF) in 117 preputial samples, collected by scraping, from bulls from Alentejo region. The actual prevalence of BGC, considering the sensitivity and specificity of the test was 52.89% of animals and 80 % of farms. It was also performed a comparison between two BGC diagnostic tests, bacterial isolation and DIF. The bacterial isolation was difficult to perform and the presence of bacterial contaminants was very problematic, leading to false-negative results. The presence of bacterial contaminants in bacterial isolation was problematic, leading to false-negative results. Its correlation with DIF was quite low, and DIF proved to be much more sensitive.

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A infertilidade é um problema actual que afecta cerca de 8 a 12% dos casais em idade fértil, sendo 50% dos casos atribuídos ao factor masculino. A exposição ocupacional e/ou ambiental a metais pesados representa uma das suas principais causas. O chumbo, o cádmio e o crómio são metais com elevada utilização industrial e muito persistentes no ambiente, sendo motivo de grande preocupação devido aos seus efeitos na saúde reprodutiva dos trabalhadores e da população em geral. Neste trabalho estudaram-se os efeitos do cloreto de chumbo (PbCl2), cloreto de cádmio (CdCl2) e cromato de potássio (K2CrO4) na fertilidade, usando como modelo ratinhos machos ICR-CD1. Os ratinhos foram injectados subcutaneamente com 74 e 100 mg de PbCl2/kg pc ou com 5 e 10 mg de K2CrO4/kg pc, respectivamente, durante 4 dias consecutivos ou com 1, 2 e 3 mg de CdCl2/kg pc numa única injecção. Nos ensaios com PbCl2 e K2CrO4 os animais foram sacrificados 5 e 35 dias após o início da exposição, enquanto que nos ensaios com CdCl2 os animais foram sacrificados após 24 horas e 35 dias. O cloreto de chumbo não alterou a histologia do testículo nem do epidídimo, mas induziu um aumento da percentagem de células em fase S no testículo. O cloreto de chumbo alterou também alguns parâmetros dos espermatozóides, tais como a motilidade, morfologia e integridade do acrossoma. Contudo, não foram observados efeitos na integridade do DNA ou na estrutura da cromatina. O cloreto de cádmio induziu lesões severas e não reversíveis nos testículos que, após 35 dias, reverteram em necrose testicular. O cloreto de cádmio alterou ainda as subpopulações de células testiculares após 24 horas e induziu IMS no testículo após 35 dias. Em consequência das lesões no testículo, a densidade espermática foi severamente afectada após 35 dias. A exposição ao cloreto de cádmio afectou também a morfologia, a motilidade e a integridade acrossómica nos espermatozóides. O cloreto de cádmio induziu ainda fragmentação do DNA nestas células após 35 dias. O cromato de potássio alterou a morfologia dos espermatozóides e a integridade do acrossoma, sobretudo nos animais sacrificados após 35 dias. Verificou-se ainda uma redução da motilidade dos espermatozóides. Não foram detectados efeitos genotóxicos nos espermatozóides, devido à acção do K2CrO4 nas doses testadas. Dos parâmetros avaliados neste trabalho, destacam-se duas novas abordagens, nomeadamente o programa informático Snakes e a análise do conteúdo em DNA de células de testículo, a partir de material incluído em parafina. O Snakes permitiu fazer medições rigorosas do diâmetro dos tubos seminíferos, enquanto que a fixação de amostras de testículo de ratinhos em formol tamponado e inclusão em parafina resultou numa boa preservação do DNA, possibilitando assim a quantificação das subpopulações de células testiculares por citometria de fluxo. Os resultados obtidos para os diferentes parâmetros testados indicam que a motilidade dos espermatozóides e a integridade do acrossoma sejam parâmetros sensíveis à toxicidade de metais. O acrossoma aparenta ser um dos principais alvos da toxicidade dos metais e cuja reacção acrossómica prematura pode reduzir a capacidade do espermatozóide para fertilizar o oócito. Assim, este trabalho representa uma contribuição para uma melhor compreensão dos efeitos do chumbo, cádmio e crómio na fertilidade masculina.

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Celiac disease (CD) is an autoimmune enteropathy, characterized by an inappropriate T-cell-mediated immune response to the ingestion of certain dietary cereal proteins in genetically susceptible individuals. This disorder presents environmental, genetic, and immunological components. CD presents a prevalence of up to 1% in populations of European ancestry, yet a high percentage of cases remain underdiagnosed. The diagnosis and treatment should be made early since untreated disease causes growth retardation and atypical symptoms, like infertility or neurological disorders. The diagnostic criteria for CD, which requires endoscopy with small bowel biopsy, have been changing over the last few decades, especially due to the advent of serological tests with higher sensitivity and specificity. The use of serological markers can be very useful to rule out clinical suspicious cases and also to help monitor the patients, after adherence to a gluten-free diet. Since the current treatment consists of a life-long glutenfree diet, which leads to significant clinical and histological improvement, the standardization of an assay to assess in an unequivocal way gluten in gluten-free foodstuff is of major importance.

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Paragangliomas are rare tumors, with a reported incidence of 2–8 per million. They are chromaffin cell tumors that develop from the neural crest cells and may be divided in tumors derived from the parasympathetic or sympathetic ganglia. We report a case a of a 32-year-old nulliparous woman, referred to our Infertility Clinic. Abdomino-pelvic ultrasound identified a large abdominopelvic tumor, without ovarian origin (both ovaries were identified and had normal morphology). Magnetic Resonance Imaging suggested a right adnexal multicystic, vascularized mass close to iliac vessels and questioning an ovarian origin. At exploratory laparotomy, a 10 cm encapsulated and vascularized mass was found beginning just below right renal artery and extending to the level of the broad ligament. This mass was totally excised and histopathology was consistent with Paraganglioma.

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Background. HIV infected women have higher rates of infertility. Objective. The purpose of this literature review is to evaluate the effectiveness of fresh IVF/ICSI cycles in HIV infected women. Materials and Methods. A search of the PubMed database was performed to identify studies assessing fresh nondonor oocyte IVF/ICSI cycle outcomes of serodiscordant couples with an HIV infected female partner. Results and Discussion. Ten studies met the inclusion criteria. Whenever a comparison with a control group was available, with the exception of one case, ovarian stimulation cancelation rate was higher and pregnancy rate (PR) was lower in HIV infected women. However, statistically significant differences in both rates were only seen in one and two studies, respectively. A number of noncontrolled sources of bias for IVF outcome were identified. This fact, added to the small size of samples studied and heterogeneity in study design and methodology, still hampers the performance of a meta-analysis on the issue. Conclusion. Prospective matched case-control studies are necessary for the understanding of the specific effects of HIV infection on ovarian response and ART outcome.

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Summary : The hypothalamus represents less than 1 % of the total volume of the brain tissue, yet it plays a crucial role in endocrine regulations. Puberty is defined as a process leading to physical, sexual and psychosocial maturation. The hypothalamus is central to this process, via the activation of GnRH neurons. Pulsatile GnRH secretion, minimal during childhood, increases with the onset of puberty. The primary function of GnRH is to regulate the growth, development and function of testes in boys and ovaries in girls, by stimulating the pituitary gland secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Several factors contribute to the timing of puberty, including sex and ethnicity, genetics, dietary intake and energy expenditure. Kisspeptins constitute a family of small peptides arising from the proteolytic cleavage of metastin, a peptide with 54 amino acids initially purified from human placenta. These kisspeptins were the subject of much attention following their discovery because of their antimetastatic properties, but it was more recently that their determining role in the reproductive function was demonstrated. It was shown that kisspeptins are ligands of a receptor, GPR54, whose natural inactivating mutation in humans, or knockout in the mouse, lead to infertility. GnRH neurons play a pivotal role in the central regulation of fertility. Kisspeptin greatly increases GnRH release and GnRH neuron firing activity, but the neurobiological mechanisms for these actions are unknown. Gprotein-coupled receptor 54, the receptor for kisspeptin, is expressed by GnRH neurons as well as other hypothalamic neurons, suggesting that both direct and indirect effects are possible. In the first part of my thesis, we investigated a possible connection between the acceleration of sexual development induced by leptin and hypothalamic metastin neurons. However, the data generated by our preliminary experiments confirmed that the commercially available antibodies are non-specific. This finding constituted a major drawback for our studies, which relied heavily upon the neuroanatomical study of the hypothalamic metastinergic pathways to elucidate their sensitivity to exogenous leptin. Therefore, we decided to postpone any further in vivo experiment until a better antibody becomes available, and focused on in vitro studies to better understand the mechanisms of action of kisspeptins in the modulation of the activity of GnRH neurons. We used two GnRH-expressing neuronal cell lines to investigate the cellular and molecular mechanisms of action of metastin in GnRH neurons. We demonstrated that kisspeptin induces an early activation of the MAP kinase intracellular signaling pathway in both cell lines, whereas the SAP/JNK or the Akt pathways were unaffected. Moreover, we found an increase in GnRH mRNA levels after 6h of metastin stimulation. Thus, we can conclude that kisspeptin regulates GnRH neurons both at the secretion and the gene expression levels. The MAPK pathway is the major pathway activated by metastin in GnRH expressing neurons. Taken together, these data provide the first mechanism of action of kisspeptin on GnRH neurons. Résumé : L'hypothalamus est une zone située au centre du cerveau, dont il représente moins de 1 du volume total. La puberté est la période de transition entre l'enfance et l'age adulte, qui s'accompagne de transformations somatiques, psychologiques, métaboliques et hormonales conduisant à la possibilité de procréer. La fonction principale de la GnRH est la régulation de la croissance, du développement et de la fonction des testicules chez les hommes, et des ovaires chez les femmes en stimulant la sécrétion de l'hormone lutéinisante (LH) et de l'hormone folliculostimulante (FSH) par la glande hypophysaire. Plusieurs facteurs contribuent au déclanchement de la puberté, y compris le sexe et l'appartenance ethnique, la génétique, l'apport alimentaire et la dépense énergétique. Les Kisspeptines constituent une famille de peptides résultant de la dissociation proteolytique de la métastine, un peptide de 54 acides aminés initialement purifié à partir de placenta humain. Ces kisspeptines ont fait l'objet de beaucoup d'attention à la suite de leur découverte en raison de leurs propriétés anti-metastatiques, et c'est plus récemment que leur rôle déterminant dans la fonction reproductive a été démontré. Les kisspeptines sont des ligands du récepteur GPR54, dont la mutation inactivatrice chez l'homme, ou le knockout chez la souris, conduisent à l'infertilité par hypogonadisme hypogonadotrope. Les neurones à GnRH jouent un rôle central dans le règlement des fonctions reproductrices et la kisspeptine stimule l'activité des neurones à GnRH et la libération de GnRH par ces neurones. Toutefois, les mécanismes neurobiologiques de ces actions ne sont pas connus. Dans la première partie de ma thèse, nous avons étudié le lien potentiel entre l'accélération du développement sexuel induite par la leptine et les neurones hypothalamiques à metastine. Les données générées dans cette première série d'expériences ont malheureusement confirmé que les anticorps anti-metastine disponibles dans le commerce sont aspécifiques. Ceci a constitué un inconvénient majeur pour nos études, qui devaient fortement s'appuyer sur l' étude neuroanatomique des neurones hypothalamiques à metastine pour évaluer leur sensibilité à la leptine exogène. Nous avons donc décidé de focaliser nos travaux sur une étude in vitro des mécanismes d'action de la kisspeptine pour moduler l'activité des neurones à GnRH. Nous avons utilisé deux lignées de cellules neuronales exprimant la GnRH pour étudier les mécanismes d'action cellulaires et moléculaires de la metastine dans des neurones. Nous avons ainsi pu démontrer que la kisspeptine induit une activation précoce de la voie f de signalisation de la MAP kinase dans les deux lignées cellulaires, alors que nous n'avons observé aucune activation de la voie de signalisation de la P13 Kinase et de la SAP/JNK. Nous avons en outre démontré une augmentation de l'expression de la GnRH par la stimulation avec la Kisspeptine. L'ensemble de ces données contribue à élucider le mécanisme d'action avec lequel la kisspeptine agit dans les neurones à GnRH, en démontrant un effet sur l'expression génique de la GnRH. Nous pouvons également conclure que la voie de la MAPK est la voie principale activée par la metastine dans les neurones exprimant la GnRH.

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Primary ciliary dyskinesia (PCD) is an autosomal recessive disease with an incidence estimated between 1:2,000 and 1:40,000. Ciliated epithelia line the airways, nasal and sinus cavities, Eustachian tube and fallopian tubes. Congenital abnormalities of ciliary structure and function impair mucociliary clearance. As a consequence, patients present with chronic sinopulmonary infections, recurrent glue ear and female subfertility. Similarities in the ultrastructure of respiratory cilia, nodal cilia and sperm result in patients with PCD also presenting with male infertility, abnormalities of left-right asymmetry (most commonly situs inversus totalis) and congenital heart disease. Early diagnosis is essential to ensure specialist management of the respiratory and otological complications of PCD. Diagnostic tests focus on analysis of ciliary function and electron microscopy structure. Analysis is technically difficult and labour intensive. It requires expertise for interpretation, restricting diagnosis to specialist centres. Management is currently based on the consensus of experts, and there is a pressing need for randomised clinical trials to inform treatment.

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Prognosis of breast cancer women has been dramatically improved by the adjuvant therapies. As the vast majority of patients are cured, the importance of long-term quality of life is growing. The question of the maternity is an essential concern for the young women who have to receive chemotherapy or several years of endocrine therapy. This problem is often underestimated and may lead to emotional distress, depression or anxiety. A regional multidisciplinary working group was set up in order to offer optimal information about fertility and cancer as to propose specific therapeutic reproduction options, when applicable. Specificity of the young patients' breast cancer, the treatment approaches and their impact on fertility are discussed in this paper.

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Adiponectin is an adipokine, present in the circulation in comparatively high concentrations and different molecular weight isoforms. For the first time, the distribution of these isoforms in serum and follicular fluid (FF) and their usefulness as biological markers for infertility investigations was studied. In vitro study. University based hospital. Fifty-four women undergoing intracytoplasmic sperm injection (ICSI). Oocytes were retrieved, fertilized in vitro using ICSI, and the resulting embryos transferred. Serum was collected immediately prior to oocyte retrieval. Adiponectin isoforms (high molecular weight (HMW), medium and low molecular weight) were determined in serum and FF. Total adiponectin and the different isoform levels were compared with leptin and ovarian steroid concentrations. Adiponectin isoforms in serum and FF. Adiponectin isoform distribution differed between serum and FF; the HMW fraction made up half of all adiponectin in the serum but only 23.3% in the FF. Total and HMW adiponectin in both serum and FF correlated negatively with the body mass index and the concentration of leptin. No correlations were observed for total adiponectin or its isoforms with estradiol, progesterone, anti-Mullerian hormone, inhibin B, or the total follicle stimulating hormone (FSH) dose administered during the ovarian stimulation phase. This study shows for the first time that adiponectin isoform distribution varies between the serum and FF compartments in gonadotropin stimulated patients. A trend towards higher HMW adiponectin serum levels in successful ICSI cycles compared to implantation failures was observed; studies with larger patient groups are required to confirm this observation.

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Sertoli cells (SCs), the only somatic cells within seminiferous tubules, associate intimately with developing germ cells. They not only provide physical and nutritional support but also secrete factors essential to the complex developmental processes of germ cell proliferation and differentiation. The SC transcriptome must therefore adapt rapidly during the different stages of spermatogenesis. We report comprehensive genome-wide expression profiles of pure populations of SCs isolated at 5 distinct stages of the first wave of mouse spermatogenesis, using RNA sequencing technology. We were able to reconstruct about 13 901 high-confidence, nonredundant coding and noncoding transcripts, characterized by complex alternative splicing patterns with more than 45% comprising novel isoforms of known genes. Interestingly, roughly one-fifth (2939) of these genes exhibited a dynamic expression profile reflecting the evolving role of SCs during the progression of spermatogenesis, with stage-specific expression of genes involved in biological processes such as cell cycle regulation, metabolism and energy production, retinoic acid synthesis, and blood-testis barrier biogenesis. Finally, regulatory network analysis identified the transcription factors endothelial PAS domain-containing protein 1 (EPAS1/Hif2α), aryl hydrocarbon receptor nuclear translocator (ARNT/Hif1β), and signal transducer and activator of transcription 1 (STAT1) as potential master regulators driving the SC transcriptional program. Our results highlight the plastic transcriptional landscape of SCs during the progression of spermatogenesis and provide valuable resources to better understand SC function and spermatogenesis and its related disorders, such as male infertility.