Orientadores: Wilma de Grava Kempinas, Debora Cristina Damasceno / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T13:24:37Z (GMT). No. of bitstreams: 1 Amorim_ElaineManoelaPorto_M.pdf: 16324180 bytes, checksum: c70c3ef2e2f1da1ec0592d601a83f795 (MD5) Previous issue date: 2007 / Resumo: Diabetes mellitus é um grupo de desordens metabólicas de etiologia múltipla, caracterizado por defeitos na secreção e/ou ação da insulina. As causas da doença podem ser genéticas e/ou ambientais. O diabete é uma das complicações metabólicas mais comuns durante a gestação, associado a um aumento nos riscos maternos e morbidade neonatal. Estudos epidemiológicos e experimentais têm demonstrado que um meio intra-uterino anormal durante a vida fetal pode afetar o desenvolvimento, causando prejuízo do crescimento fetal, e aumentar a susceptibilidade da prole em desenvolver doenças crônicas na vida adulta. A hipótese da ?programação fetal? sugere que as adaptações que ocorrem durante o desenvolvimento do embrião, em resposta a um meio adverso, provocam alterações permanentes na estrutura e fisiologia do organismo. Já foi demonstrado que o diabete materno e a hiperglicemia induzida experimentalmente causam anormalidades no crescimento fetal, o que está associado com o desenvolvimento de doenças cardiovasculares e diabete tipo 2 na vida adulta. Neste contexto, o objetivo do presente trabalho foi investigar as conseqüências do meio intra-uterino anormal, decorrente do diabete materno, no desenvolvimento e função reprodutiva na pré-puberdade, puberdade e maturidade sexual da prole masculina de ratas em que o diabete foi induzido experimentalmente antes do acasalamento. Foram utilizadas 74 ratas Wistar com 90 dias de idade, divididas em dois grupos experimentais: grupo diabético (n=59), que recebeu, via intravenosa, 40 mg/kg de estreptozotocina, e grupo controle (n=17), que recebeu tampão citrato (0,1M; pH 6,5) nas mesmas condições experimentais. Só foram incluídas no estudo as ratas que apresentaram valores de glicemia iguais ou superiores a 200mg/dl sete dias após a indução (n=55). Todas as fêmeas foram mortas após o desmame dos filhotes. A prole masculina foi avaliada quanto a parâmetros espermáticos e hormonais nas diferentes fases do desenvolvimento sexual. O resultado da prenhez foi prejudicado nas ratas do grupo diabético. Independente do grupo experimental, não foram observadas malformações externas nos recém-nascidos viáveis. O peso corporal e os níveis plasmáticos de glicose, avaliados no terceiro dia pós-natal, foram menores na prole masculina de ratas diabéticas, comparado a prole controle. Na prole de ratas diabéticas, foi observado atraso no tempo (dias) da descida testicular e separação prepucial. Em todas as idades analisadas não houve diferenças estatísticas nos níveis de testosterona, glicemia, histologia dos testículos e epidídimo e grau de maturação do epitélio germinativo. Nos ratos adultos também não foram observadas alterações na morfologia espermática, número de células de Sertoli e dinâmica do processo espermatogênico. Por outro lado, o peso de órgãos reprodutivos, assim como as reservas espermáticas e tempo de trânsito dos espermatozóides no epidídimo, nos animais pré-púberes e adultos, foram alterados de maneira andrógenoindependente. O conjunto dos resultados obtidos mostraram que o meio intrauterino hiperglicêmico, causado pelo diabete materno, prejudicou o desenvolvimento fetal, e provocou alterações nas funções metabólicas e reprodutivas da prole masculina ao longo do desenvolvimento sexual / Abstract: Diabetes melllitus is a group of metabolic disorders of multiple etiology, characterized by defects in the secretion and/or action of insulin. The causes of the disease can be genetic and/or environmental. Diabetes is one of the most common metabolic complications during pregnancy and is associated with an increased risk of maternal and neonatal morbidities. Epidemiological and experimental studies have demonstrated that an abnormal intrauterine environment during fetal life can affect the development, causing impairment of fetal growth and increasing the susceptibility of the offspring to developing chronic diseases in adulthood. The hypothesis of ?fetal programming? suggests that the adaptations that occur during embryonic development in response to an adverse medium provoke permanent alterations in the structure and physiology of the organism. It was already demonstrated that maternal diabetes and experimentally induced hyperglycemia cause abnormalities in fetal growth, which is associated with the development of cardiovascular diseases and type 2 diabetes in adulthood. In this context, the objective of present study was to investigate the consequences of the abnormal intrauterine environment, resulting from maternal diabetes, in the development and reproductive function, at pre-puberty, puberty and during sexual maturity, in the male offspring of rats in which diabetes was experimentally induced before mating. Seventy-four Wistar rats 90- days old were utilized, divided into two experimental groups: diabetic group (n=59) that received intravenously streptozotocin 40mg/kg body weight and control group (n=17) that received intravenously citrate buffer (0.1M; pH 6.5) in the same experimental conditions. Seven days after the induction the glicemia was measured and only rats presenting concentrations of 200 mg/dl or higher were considered severely diabetic and included in the study (n=55). All the females were killed after offspring weaning. The male offspring were evaluated in different phases of sexual maturation for sperm parameters and hormonal levels. The gestational outcome was impaired in the rats of the diabetic group. Independently of the experimental group, there were no external malformations in the viable newborns. Body weight and plasma glucose levels, evaluated on the third postnatal day, were lower in the male offspring of diabetic dams, compared to control. The times (days) of testicular descent and preputial separation were significantly delayed in the pups of diabetic dams. In all the ages evaluated there were no significant statistical differences in testosterone levels, glycemia, histology of the testis and epididimys and maturation degree of the germinal epithelium. Moreover, in adult rats no alterations were observed in sperm morphology, number of Sertoli cells and dynamics of the spermatogenic process. On the other hand, the weights of reproductive organs, as well as sperm reserves and sperm transit time in the epididymis were impaired in the prepubertal and adult rats, in an androgenindependent manner. Taken together, the findings obtained showed that the hyperglycemic intrauterine environment, caused by maternal diabetes, impaired fetal development, and provoked alterations in the metabolic and reproductive functions of the male offspring throughout sexual development / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural

Orientadores: Andréa Trevas Maciel Guerra, Roberto Benedito de Paiva e Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-23T14:10:17Z (GMT). No. of bitstreams: 1 Oliveira_MailmedeSouza_M.pdf: 1438396 bytes, checksum: 1208347d3b020b53a72b4452eaa651e3 (MD5) Previous issue date: 2013 / Resumo: Objetivo: Conhecer algumas das situações vivenciadas pelos pais de crianças com ambiguidade genital (AG), bem como aspectos da condução desses casos por profissionais de saúde. Métodos: Tratou-se de uma análise quantitativa com algumas questões abertas a partir de entrevista com genitores de 30 crianças com AG nascidas a partir de 2006 e atendidas em um serviço de referência em distúrbios da diferenciação do sexo em hospital público universitário. Vinte e oito mães e 17 pais foram entrevistados por meio de questionário sobre o período pré-natal, o momento da constatação da AG, a condução do caso pelos profissionais de saúde e as situações vivenciadas após a detecção do problema. Resultados: Em somente dois casos a ultrassonografia obstétrica havia detectado a AG. O fato foi comunicado pelo pediatra em 21 casos e revelado pelos pais a parentes (25), mas menos frequentemente a amigos (12). Havia dificuldade dos pais em falar sobre o assunto (14), e estes evitavam expor os genitais do bebê perante outras pessoas (17). Dezenove crianças chegaram sem registro; durante a investigação muitos pais (16) já tinham convicção sobre o sexo, utilizando o pronome correspondente (ele ou ela) (13). Onze crianças chegaram registradas, a maioria com autorização do pediatra (7) e com base apenas no exame dos genitais (7); em seis casos os pais não estariam dispostos a mudar o registro se necessário. Conclusões: Houve condução inadequada por parte das equipes médicas em alguns casos e falta de informação das famílias, gerando confusão e sentimentos negativos. É importante a divulgação de orientações práticas para profissionais de saúde e familiares, para melhor condução dos casos e aceitação dessa condição / Abstract: Aim: To know some of the situations experienced by the parents of children with ambiguous genitalia (AG), as well as issues related to management of these cases by health professionals. Methods: This was a quantitative analysis with some open questions from interviews with 30 parents of children born with AG since 2006 and attended in a reference service on disorders of sex disorders in a public university hospital. Twenty eight mothers and 17 fathers were interviewed by questionnaire about the prenatal period, the moment AG was noticed, case management by health professionals and the situations experienced after the condition was detected. Results: In only two cases obstetric ultrasound had detected the AG. The fact was reported by pediatricians in 21 cases and revealed by the parents to relatives (25), but less frequently to friends (12). They had difficulty in talking about the subject (14) and in 17 cases they avoided exposing the baby's genitalia to strangers. Nineteen children arrived without a sex assignment, but many of their parents were already convinced about the sex of the baby during the investigation (16), using the corresponding pronoun (he or she) (13). Eleven children had already been registered, most with permission of the pediatrician (7) and based only on examination of the genitals (7); in six cases the parents would not be willing to change the registry if necessary. Conclusions: There was mismanagement on the part of medical personnel in some cases and lack of information for families, generating confusion and negative feelings. It is important to disseminate practical guidelines to health professionals to achieve better management of the cases and to family members to improve acceptance of the condition / Mestrado / Saude da Criança e do Adolescente / Mestra em Saúde da Criança e do Adolescente

Double standard effects in inferences about quality of parenting and adult sexual outcomes for children were investigated under five conditions of single-parent sexual behavior. The sample comprised six hundred married parents from three major metropolitan areas in Texas. Subjects were administered a scenario about a hypothetical single parent family. The scenario varied with respect to parent gender, child gender, and type of parental sexual activity (e.g., abstinence, limited affairs away from home, involvement with a live-in lover, frequent partners spending the night, and a control condition containing no sexual message). Subjects were asked to rate a parent from the scenario on quality of parenting and predict the adult sexual behavior of the child. Hypothesized double standard effects did not emerge. A double standard in judgments about sexually active single parents and parenting did appear. Main effects were found for child gender and sexual lifestyle of the parent (e.g., parents with boys rated less favorably than parents with girls; promiscuous fathers were rated lower than promiscuous mothers). Several interaction effects among parent gender, child gender, and sexual lifestyle condition were also found (e.g., promiscuous parents were rated lower as parents and seen as negatively influencing the child's sexual development). Recommendations for future research include refining the two scales used in this study; extending the study to include data from single parents; examining whether the judgments of sexually active single parents affect the quality and quantity of interactions others have with either the parent or child.

No description available.

Sexual development begins with the process by which the bipotential gonads of the embryonic urogenital ridge develop into either testes or ovaries. In the mouse, sex determination occurs at around 11.5 dpc and depends on the presence or absence of the Y chromosome and the associated activity of the testis-determining gene, Sry, in supporting cell precursors. The mutually antagonistic male and female developmental pathways are regulated by many cellular and molecular processes, disruption of which can lead to disorders of sex development (DSDs). However, many of the molecular mechanisms regulating the differentiation of the two gonads are still unknown. The boygirl (byg) mutant was identified in an ENU-based forward genetic screen for embryos with gonadal abnormalities. On the C57BL/6J background, XY byg/byg homozygotes exhibited complete embryonic gonadal sex reversal. The defective gene in byg, Map3k4, is a component of the mitogen-activated protein (MAP) kinase signalling pathway and provides the first evidence for a function of this pathway in sex determination. This thesis describes experiments aimed at investigating the cellular and molecular basis of the sex reversal phenotype associated with the XY Map3k^4byg/byg mutant. Cellular characterisations revealed a defect in male-specific proliferation at 11.5 dpc, which was attributed to a defect in Sry up-regulation. Elucidation of the downstream kinases activated by MAP3K4 during sex determination was attempted, with particular focus on identifying a role for p38α MAP kinase (MAPK). Using a conditional knockout approach, the function of p38α in Steroidogenic factor-1 (Sf1)-positive somatic cells was assessed. However, specific inactivation in these cells did not affect gonad development. Conditional inactivation of Map3k4 itself in these Sf1¬-positive cells also did not disrupt gonad development, suggesting that this pathway is either initiated in a different cell lineage or at an earlier stage than deletion driven by Sf1-Cre can disrupt. Conditional inactivation of p38α in the Müllerian duct mesenchyme and ovarian granulosa cells using Amhr2-Cre did reveal a function for p38α in female fertility, but did not disrupt embryonic sexual development. Gene knockdown in organ culture was attempted to determine a role for multiple p38 MAPKs in all cell types of the gonad. Therefore, this thesis details further characterisations of a novel signalling pathway important for the expression of Sry, focussing on the role of the p38 MAPKs.

It is generally thought that in amphibians, thyroid hormones (THs) regulate metamorphosis, while sex steroids (estrogens and androgens) regulate gonadal differentiation. However, inhibition of TH synthesis in frogs alters gonadal differentiation, suggesting instead that these two endocrine axes interact during development. Specifically, THs may be involved in male development, while estrogens may inhibit tadpole metamorphosis. However, we do not currently know the mechanisms that account for these interactions, let alone how such mechanisms may differ between species. To develop and test new hypotheses on the roles of sex steroids and THs, I first examined transcriptional profiles (mRNA) of enzymes and receptors related to sex steroids and THs during embryogenesis and metamorphosis in Silurana tropicalis. Tadpoles were exposed to either an estrogen synthesis inhibitor (fadrozole) or TH (triiodothyronine, T3) during early larval or tadpole development. Acute exposures of S. tropicalis to fadrozole or T3 during early development resulted in increased expression of androgen- and TH-related genes in whole body larvae, while chronic exposure to fadrozole during metamorphosis affected gonadal differentiation but did not affect tadpole development. On the other hand, acute exposure to T3 during metamorphosis increased the expression of androgen-related transcripts both in the brain and gonad. In S. tropicalis, the results suggested that cross-talk is primarily in one direction (i.e., effect of THs on the reproductive axis) with a strong relationship between TH and androgen status. Lastly, I established developmental transcript profiles and investigated T3 regulation of brain and gonad transcripts in Engystomops pustulosus. I then compared these results with S. tropicalis and an earlier study in Lithobates pipiens. While each species developed with similar profiles, they differed in their response to T3. Exposure to T3 resulted in either an increase in androgen-related genes (S. tropicalis) or a decrease in estrogen-related genes (E. pustulosus and L. pipiens). In conclusion, these data demonstrated that cross-talk mechanisms differ among these three evolutionary separate species, but in all cases, T3 appears to affect the balance of sex steroids, stimulating the androgen system and providing potential mechanisms of the masculinising effects of THs. These results will contribute to understanding the mechanisms of hormone interactions and their evolutionary basis in frogs.

Striatin family proteins contain a caveolin binding domain, a coiled-coil motif, a calmodulin binding domain, and a WD-repeat domain. Homologs of striatin protein have been However, our knowledge of the function and the molecular mechanism of fungal striatin homologs is limited. Based on the conserved sequences of functional domains, I hypothesized that the fungal striatin orthologs also act as scaffolding proteins that are functionally conserved among fungal species and involved in multiple types of development in the diverse kingdom Mycota. I used reverse genetic strategies to study the function of the Aspergillus nidulans striatin ortholog (strA) and the Colletotrichum graminicola striatin ortholog (str1). In assays of sexual development, the strA deletion strain (ΔstrA) produces fewer ascospores with smaller cleistothecia, while the str1 deletion strain (Δstr1) is defective in perithecia development. The ΔstrA phenotypes indicate that StrA is associated with ascosporogenesis in cleistothecia. Both ΔstrA and Δstr1 are reduced in radial growth and in conidia production. The Δstr1 strain is also altered in its spiral growth pattern and morphology of conidia and hyphopodia, but it produces appressoria similar to wild type. The pairing of nitrate non-utilizing mutants demonstrates that Str1 is required for hyphal fusion. In pathogenicity, Δstr1 is less virulent in maize anthracnose leaf blight and stalk rot. The phenotypes of Δstr1 are complemented by the Fusarium verticillioides striatin ortholog (fsr1), indicating that Fsr1 and Str1 are functionally conserved. Over-expression of StrA reveals its positive role in conidiation and the sexual production. StrA::eGFP localizes mainly to the endoplasmic reticulum. After comparing the results from these two species and other studied fungal species, I suggest that fungal striatins are involved in five types of development including hyphal growth, hyphal fusion, conidiation, sexual development, and virulence, and propose a model of fungal striatin protein interactions to account for these diverse phenotypes.

It is generally thought that in amphibians, thyroid hormones (THs) regulate metamorphosis, while sex steroids (estrogens and androgens) regulate gonadal differentiation. However, inhibition of TH synthesis in frogs alters gonadal differentiation, suggesting instead that these two endocrine axes interact during development. Specifically, THs may be involved in male development, while estrogens may inhibit tadpole metamorphosis. However, we do not currently know the mechanisms that account for these interactions, let alone how such mechanisms may differ between species. To develop and test new hypotheses on the roles of sex steroids and THs, I first examined transcriptional profiles (mRNA) of enzymes and receptors related to sex steroids and THs during embryogenesis and metamorphosis in Silurana tropicalis. Tadpoles were exposed to either an estrogen synthesis inhibitor (fadrozole) or TH (triiodothyronine, T3) during early larval or tadpole development. Acute exposures of S. tropicalis to fadrozole or T3 during early development resulted in increased expression of androgen- and TH-related genes in whole body larvae, while chronic exposure to fadrozole during metamorphosis affected gonadal differentiation but did not affect tadpole development. On the other hand, acute exposure to T3 during metamorphosis increased the expression of androgen-related transcripts both in the brain and gonad. In S. tropicalis, the results suggested that cross-talk is primarily in one direction (i.e., effect of THs on the reproductive axis) with a strong relationship between TH and androgen status. Lastly, I established developmental transcript profiles and investigated T3 regulation of brain and gonad transcripts in Engystomops pustulosus. I then compared these results with S. tropicalis and an earlier study in Lithobates pipiens. While each species developed with similar profiles, they differed in their response to T3. Exposure to T3 resulted in either an increase in androgen-related genes (S. tropicalis) or a decrease in estrogen-related genes (E. pustulosus and L. pipiens). In conclusion, these data demonstrated that cross-talk mechanisms differ among these three evolutionary separate species, but in all cases, T3 appears to affect the balance of sex steroids, stimulating the androgen system and providing potential mechanisms of the masculinising effects of THs. These results will contribute to understanding the mechanisms of hormone interactions and their evolutionary basis in frogs.

It is generally thought that in amphibians, thyroid hormones (THs) regulate metamorphosis, while sex steroids (estrogens and androgens) regulate gonadal differentiation. However, inhibition of TH synthesis in frogs alters gonadal differentiation, suggesting instead that these two endocrine axes interact during development. Specifically, THs may be involved in male development, while estrogens may inhibit tadpole metamorphosis. However, we do not currently know the mechanisms that account for these interactions, let alone how such mechanisms may differ between species. To develop and test new hypotheses on the roles of sex steroids and THs, I first examined transcriptional profiles (mRNA) of enzymes and receptors related to sex steroids and THs during embryogenesis and metamorphosis in Silurana tropicalis. Tadpoles were exposed to either an estrogen synthesis inhibitor (fadrozole) or TH (triiodothyronine, T3) during early larval or tadpole development. Acute exposures of S. tropicalis to fadrozole or T3 during early development resulted in increased expression of androgen- and TH-related genes in whole body larvae, while chronic exposure to fadrozole during metamorphosis affected gonadal differentiation but did not affect tadpole development. On the other hand, acute exposure to T3 during metamorphosis increased the expression of androgen-related transcripts both in the brain and gonad. In S. tropicalis, the results suggested that cross-talk is primarily in one direction (i.e., effect of THs on the reproductive axis) with a strong relationship between TH and androgen status. Lastly, I established developmental transcript profiles and investigated T3 regulation of brain and gonad transcripts in Engystomops pustulosus. I then compared these results with S. tropicalis and an earlier study in Lithobates pipiens. While each species developed with similar profiles, they differed in their response to T3. Exposure to T3 resulted in either an increase in androgen-related genes (S. tropicalis) or a decrease in estrogen-related genes (E. pustulosus and L. pipiens). In conclusion, these data demonstrated that cross-talk mechanisms differ among these three evolutionary separate species, but in all cases, T3 appears to affect the balance of sex steroids, stimulating the androgen system and providing potential mechanisms of the masculinising effects of THs. These results will contribute to understanding the mechanisms of hormone interactions and their evolutionary basis in frogs.

In this thesis I investigate whether human sexual preferences develop through sexual imprinting. Sexual imprinting is the acquisition of sexual preferences through non-rewarded experiences with parents and siblings during an early sensitive period and it is known to exist in many other animals. Learning is often sex specific so that males, for instance, learn to prefer as sexual partners individuals that look like their mother, and avoid individuals that look like their father. First, sexual imprinting in animals and humans is reviewed and compared to prevailing evolutionary views presupposing genetically determined sexual preferences. Further, by means of web surveys, I have explored the relationship between childhood exposure to parents with certain natural and cultural traits and sexual attraction to these traits in a partner. Cultural traits were included because it is unlikely that preferences for them are genetically determined adaptations. Parental effects varied between traits. For instance, in heterosexual males, a positive effect of mother was found on attraction to smoking, but not glasses, while a negative paternal effect was found on attraction to glasses, but not smoking. However, when maternal and paternal effects were investigated for a large number of artificial and natural traits, including smoking and glasses, an overall positive effect of opposite sex parent emerged in both heterosexual males and females. Additionally, in the last study we explored a sexual preference for pregnant and lactating women. Results suggest that exposure to a pregnant and lactating mother had an effect if it occurred when the respondent was between 1,5 and 5 years old. In conclusion, these results suggest that human sexual preferences are the result of sex specific learning during a sensitive period. Sexual imprinting should therefore be recognised as a plausible explanation to human sexual preferences that deserves further scientific investigation. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.