Orientadores: Mary Anne Heidi Dolder, Frederico Falcão Salles / Texto em português e inglês / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T13:00:35Z (GMT). No. of bitstreams: 1 Brito_PedroValedeAzevedo_D.pdf: 100648281 bytes, checksum: 084741b621bdeef83fe1e691e02ad06f (MD5) Previous issue date: 2012 / Resumo: Entre as ordens de insetos alados com representantes vivos, os membros da ordem Ephemeroptera estão entre os mais antigos que existem. Suas ninfas são aquáticas e os adultos, alados, sobrevivem por pouco tempo, morrendo logo após o acasalamento. Ainda existem algumas dúvidas sobre a relação dos Ephemeroptera com os demais Pterygota, bem como algumas famílias dentro da ordem são atualmente consideradas parafiléticas. A morfologia do sistema reprodutivo masculino e dos espermatozoides dos insetos pode fornecer informações úteis para estudos filogenéticos. No entanto, tais estudos envolvendo espécies de Ephemeroptera são escassos. O objetivo deste trabalho foi estudar a morfologia do sistema reprodutivo masculino e dos espermatozoides de espécies de Ephemeroptera existentes no Brasil, analisando a variabilidade morfológica encontrada nessas espécies. No Brasil são encontradas espécies pertencentes a dez famílias de Ephemeroptera e analisamos a morfologia do sistema reprodutor masculino de seis espécies pertencentes a cinco famílias e os espermatozoides de 17 espécies pertencentes a nove famílias. Nas seis espécies a morfologia do sistema reprodutivo foi muito constante sem glândulas acessórias ou órgãos especializados no armazenamento de espermatozoides. No entanto, observamos diferentes padrões de organização da musculatura intrínseca dos ductos espermáticos, provavelmente refletindo diferenças na fisiologia reprodutiva de cada espécie. A morfologia dos espermatozoides se mostrou mais variável. As espécies da família Leptophlebiidae possuem espermatozoides aflagelados e imóveis. Nas demais famílias, os espermatozoides são flagelados e móveis. A organização do axonema se mostrou constante nas diferentes espécies com o padrão 9+9+0 típico para esses insetos. Apenas os microtúbulos acessórios mostraram variação na estrutura, podendo assumir o padrão de subunidades 13+7 ou 13+0. Os flagelos são caracterizados por apenas uma mitocôndria que se alonga por quase todo flagelo. A morfologia dos corpos acessórios dos flagelos varia entre as espécies. Parece haver correlação entre a organização das cristas mitocondriais e os corpos acessórios. A morfologia da vesícula acrossomal é variável podendo estar relacionada com diferenças na espessura do corion dos ovos. No início dos flagelos observamos o adjunto do centríolo, que acreditava-se estar ausente nos espermatozoides dos Ephemeroptera. Em uma espécie estudada o núcleo dos espermatozoides está associado paralelamente ao flagelo. Nossos resultados sugerem que os espermatozoides dos Ephemeroptera possuem variabilidade morfológica suficiente para fornecer dados para futuros estudos filogenéticos. No entanto, é preciso que mais espécies sejam estudadas aumentando a abrangência dentro do grupo. Alem disso, alguns pontos como a origem dos corpos acessórios dos espermatozoides dos Ephemeroptera precisam ser melhor estudados / Abstract: Ephemeroptera species are the oldest living winged insects. Their nymphs are aquatic and the adults are short living, dying just after mating. At the present, there are still some doubts about the phylogenetic relationships between Ephemeroptera and the other Pterygota. The morphology of the male reproductive systems and of the spermatozoa is useful to furnish data for phylogenetic studies. However, there are few studies on this subject for Ephemeroptera. This study analyzes the morphology of the male reproductive system and of the spermatozoa of Brazilian Ephemeroptera species.. Species from ten Ephemeroptera families are found in Brazil. In the present study we analyzed the male reproductive system of six species from five families. We also analyzed the sperm morphology of 17 species from nine families. The male reproductive systems analyzed were very similar in the different species, with no accessory glands or specialized organs for sperm storage. However, the intrinsic musculatures of the sperm ducts have different organization patterns, probably related to differences in the reproductive physiology of each species. Greater morphological variation was observed among the spermatozoa. Species from Leptophlebiidae family have aflagellate and immotile spermatozoa. Species from the other families have mobile and flagellate spermatozoa. The organization of the axoneme was the same in all species, with the 9+9+0 microtubule pattern, typical for this insect group. Only the accessory microtubules vary between the 13+7 and the 13+0 subunit patterns. The flagella are characterized by the presence of only one mitochondrion along the flagellum. The accessory bodies morphology may vary between the species and it seems to be correlated to the organization of the mitochondrial cristae and the accessory bodies morphology. The acrosomal vesicles have morphological variations that must be related to differences in the egg chorion thickness. A centriolar adjunct is observed at the flagellum anterior region of the spermatozoa. This structure was thought to be absent in the Ephemeroptera spermatozoa. One species studied has its nucleus laterally associated to the flagellum. Our results suggest that the spermatozoa of Ephemeroptera have enough morphological variation to furnish useful data for future phylogenetic studies. However, more species, representing different groups of the order must be studied, increasing the scope of these studies. Also some questions, such as the origin of the accessory bodies of Ephemeroptera must be further studied / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural

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No description available.

LIN-12/Notch is a conserved transmembrane receptor that is required during animal development for proper cell-fate decisions and specification. In Caenorhabditis elegans, activation of LIN-12 occurs through binding to ligand expressed by an adjacent cell. This binding event triggers two cleavage steps and results in the release of the LIN-12 intracellular domain [LIN-12(intra)], which translocates to the nucleus to form a ternary complex with two other proteins: LAG-1/Su(H)/Cbf1 and SEL-8/Mastermind/Mastermind-like. This ternary complex will then transcriptionally activate target genes via LAG-1 Binding Sites (LBSs). LAG-1 is the sole DNA-binding component within the complex, and in the absence of LIN-12(intra), can act as a transcriptional repressor. LIN-12 signal transduction can be studied in the C. elegans Vulval Precursor Cells (VPCs), which exhibit precise spatiotemporal patterning regulated by LIN-12 activity. Here, I show that LAG-1 is positively autoregulated by LIN-12 activity in cells where LIN-12 activity is high. Autoregulation is mediated by an enhancer element that contains a cluster of 18 LBSs that are located within a conserved high occupancy target region, which is a span of DNA that is pulled down promiscuously in ChIP-Seq experiments. Mutation of the LBSs abrogates preferential expression mediated by the enhancer in cells with high LIN-12 signal transduction. When the HOT region is deleted from the endogenous lag-1 locus, expression in the VPCs is strongly reduced and no overt Lag phenotype occurs. Instead, cold-sensitive vulval and egg-laying defects, reminiscent of phenotypes seen in lin-12 hypomorphs, are found. Autoregulation of lag-1, therefore, appears to contribute to the robustness of LIN-12 cell fate specification in response to stochastic environmental and genetic perturbations. Under adverse environmental conditions, C. elegans enter a state of diapause in which they form dauer larvae, which are long-lived and stress-resistant. The VPCs of dauer larvae remain developmentally arrested indefinitely until favorable conditions are reintroduced. Experimentally, this arrest can be relieved by depletion of the Forkhead transcription factor DAF-16. I show that expression of the components of the LIN-12/SEL-8/LAG-1 ternary complex are downregulated during the L2d-dauer molt (prior to dauer entry) and that this downregulation is not relieved by DAF-16 depletion. Instead, DAF-16 depletion leads to resumption of LIN-12 signaling and expression of ternary complex only in completely formed dauer larvae. These observations suggest that DAF-16 is required for the maintenance but not the initiation of blocking LIN-12 signaling. The components of the ternary complex are required to effect LIN-12 signaling. This work contributes to better understanding how these components are regulated and how their expression can affect LIN-12 -mediated cell fate decisions.

After vasectomy, the passage of sperm antigen through the epithelium of the efferent duct in the rhesus macaque probably results in immune complex deposition. Immune complexes can be visualized in the thickened basement by fluorescence microscopy. Subsequent electron microscopic evaluation, with the appearance of electron-dense deposits in the basement membrane of the efferent ducts, substantiates these findings.

Preterm birth rates have been increasing over the past several years. Currently, there are no accurate methods to predict when and if a woman will go into labor. This work developed a framework to create patient-specific parametric models of the uterus and cervix from 2D ultrasound images and cervical stiffness measurements to investigate mechanical factors surrounding preterm birth during gestation. The goals of this research are (1) to collect longitudinal data on maternal anatomy throughout pregnancy, (2) to develop a framework for the computational study of pregnancy biomechanics through verification as an in-silico mechanical test of maternal anatomy, and (3) to use the framework to investigate the mechanical factors that lead to preterm birth. Though extensive knowledge exists on how the fetus normally grows and develops during pregnancy, very little is known about normal growth and change in maternal reproductive tissues. The lack of knowledge on what constitutes a normal progression in maternal reproductive tissues thus makes it difficult to diagnose patients who are progressing abnormally, as is the case for preterm birth. Though several of the main reasons cited for preterm birth are mechanical in nature, the normal mechanics of the uterus, cervix, and fetal membrane are not well understood. This work quantifies changes to maternal reproductive anatomy across gestation via the collection of ultrasonic dimension measurements in patients who are considered at low- and high-risk for preterm, along with measurements of cervical stiffness. These measurements provide the basis for parametric patient-specific computational models of pregnant maternal reproductive anatomy. Because pregnancy is a protected environment, it is not possible to study the mechanical loading of maternal tissue in-vivo. Computational simulations of maternal anatomy have the potential to shed light on the mechanics of the gravid environment. Previous methods of generating maternal anatomy have relied on magnetic resonance images or 3D ultrasounds, which are not standard during prenatal care. Thus, the method of capturing measurements of maternal anatomy via 2D ultrasound images and parametric approach to generating solid models of maternal anatomy for use in finite element analysis provides a clinically implementable way to study pregnancy biomechanics. This work develops a workflow for generating solid models of maternal anatomy that capture the shape of the uterus and systematically verify the modeling approach in computational simulation to use as patient-specific in-silico mechanical tests. With the patient-specific data on maternal anatomy collected and the verified approach to computationally simulate maternal tissue loading, this work investigates the differences in the maternal tissue loading for patients at low- and high-risk for PTB. This was accomplished by qualitative and quantitative observation of stretch in the proximal cervix face. Quantitative comparisons were also made between patients who did and did not deliver preterm of stretch in the proximal cervix. The culmination of this work significantly adds to the knowledge of the mechanical environment of pregnancy and develops the basis for in-silico study of preterm birth, as well as at-term study, providing a basis for future study on pregnancy biomechanics.

by Siu Pik-ngan. / Questionnarie in Chinese. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 74-79). / List of Tables --- p.v / List of Figures --- p.vi / List of Appendices --- p.vii / Introduction --- p.1 / Method --- p.28 / Results --- p.36 / Discussion --- p.55 / References --- p.74 / Appendices --- p.80

Thesis (MScPhysio (Interdisciplinary Health Sciences. Physiotherapy))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The pelvic floor muscles (PFM) contribute to urinary continence and overactive PFM seem to be associated with pelvic pain syndrome (PPS). The literature indicates that ethnic differences regarding symptoms of urinary incontinence may exist. Research is needed to establish relationships between PFM function and symptoms reported by women of different ethnic groups. Objectives: To compare the PFM strength and endurance in black, white and coloured women. To investigate relationships between PFM strength, vaginal resting pressures, risk factors and symptoms associated with PFM dysfunction and PPS. Method: A cross-sectional study assessed the PFM strength and vaginal resting pressures of 122 nulliparous black (n=44), white (n=44) and coloured (n=34) university students. A self-developed questionnaire determined inclusion, demographic variables, factors affecting/factors associated with PFM strength and symptoms related to PPS. Maximum voluntary contraction pressure (cmH2O) and vaginal resting pressure (cmH2O) were measured with the Peritron TM 9300 (Cardio Design, Australia) used with the Camtech AS vaginal balloon sensor (Sandvika, Norway). Two sets of 3 maximum voluntary contractions of the PFM were recorded. Results: The mean age of the group was 22 ± 3.54 years and mean BMI of 23± 4.16 kg/m2. Black women (25 cmH2O ± 13.5) had significantly stronger PFM than white (p=0.02) or coloured (p<0.01) women, but no significant difference (p=0.78) in PFM strength existed between white (18.4 cmH2O ± 9.8) and coloured (15.6 cmH2O ± 8) women. In black women, PFM strength decreased significantly (p=0.02) between the sets, whereas no significant difference between sets was noted in the other ethnic groups. Increased PFM strength was associated with SUI (p=0.03) and amenorrhoea (p=0.01) and decreased PFM strength was associated with decreased frequency of bowel motion (p=0.01). In this sample, increased vaginal resting pressure was associated with menorrhagia (p=0.04). Conclusion: Black nulliparous women had stronger PFM than white and coloured women. There was no difference in PFM strength between white and coloured women. Endurance, as measured in this study, indicates that black women have decreased endurance of the PFM compared to white and coloured women. These findings inform the current research on ethnic differences in the prevalence of urinary incontinence. Preliminary data suggest that there was no relationship between vaginal resting pressures and symptoms of PPS and risk factors for PFM dysfunction, except for menorrhagia. / AFRIKAANSE OPSOMMING: Die bekkenvloer spiere (BVS) dra by tot urinêre kontinensie en ooraktiewe BVS kan moontlik geassosieer wees met pelviese pyn sindroom (PPS). Uit die literatuur blyk dit of daar etniese verskille bestaan in die simptome van urinere inkontinensie gerapporteer deur vroue. Navorsing is nodig om die verwantskap tussen BVS funksie en simptome wat deur pasiënte van verskillende etniese groepe gerapporteer word vas te stel. Doel: Om „n vergelyking te tref tussen BVS sterkte in swart, wit en kleurling vroue. Om vas te stel of daar assosiasies bestaan tussen BVS sterkte, rustende vaginale druklesings en risiko faktore en simptome geassosieer met bekkenvloer disfunksie en PPS. Metodologie: „n Dwarssnit studie het die BVS sterkte en rustende vaginale drukke van 122 nullipareuse swart (n=44), wit (n=44) en kleurling (n=34) universiteit studente geëvalueer. Insluiting, uitsluiting, demografiese veranderlikes, faktore wat kan affekteer/faktore geassosieer met BVS sterkte en simptome geassosier met PPS is deur „n self ontwikkelde vraelys geëvalueer. Maksimale willekeurige spiersametrekking drukke (cmH2O) en rustende vaginale drukke (cmH2O) was gemeet met „n Peritron™9300 perineometer (Cardio Design, Australië) wat saam „n vaginale ballon sensor (Camtech AS, Sandvika, Noorweë) gebruik is. Twee stelle van 3 maksimale willekeurige sametrekkings van die BVS was gemeet. Resultate: Die groep se gemiddelde ouderdom was 22±3.54 jaar en die gemiddelde liggaamsgewig indeks was 23±4.16kg/m2. Swart vroue (25 cmH2O ±13.5) het beduidend sterker BVS gehad as wit (p=0.02) en kleurling (p<0.01) vroue, maar daar was geen beduidende verskil (p=0.78) in BVS sterkte tussen wit (18.4 cmH2O ± 9.8) en kleurling (15.6 cmH2O ± 8) vroue nie. Die BVS sterkte in swart vroue het beduidend (p=0.02) verminder tussen die stelle, maar geen beduidende verskille was waargeneem in die ander etniese groepe tussen stelle. Verhoogde BVS sterkte was geassosieer met druklek (p=0.03), amenorrhoea (p=0.01) en verminderde BVS sterkte was geassosieer met verminderde frekwensie van opelyf (p=0.01). Verhoogde rustende vaginale drukke was geassosieer met menoragie in hierdie steekproef. Gevolgtrekking: Swart nullipareuse vroue het sterker BVS gehad as wit en kleurling vroue, Daar was geen verskil in BVS sterkte tussen wit en kleurling vroue nie. Uithouvermoë soos in hierdie studie getoets toon dat swart vroue verminderde uithouvermoë het i.v.m. wit en kleurling vroue. Hierdie bevindings dra by tot die huidige navorsing oor etniese verskille in die prevalensie van urinêre inkontinensie. Daar was geen verwantskap tussen vaginale rustende drukke en simptome van PPS en risiko faktore vir die ontwikkeling van bekkenvloer disfunksie, behalwe vir menoragie.

published_or_final_version / Social Work / Master / Master of Social Work

Intracavitary high dose rate (HDR) brachytherapy is a form of radiation therapy generally in which a post-surgical tissue margin is treated. The dose gradient of HDR brachytherapy is very steep, and thus small displacements of the applicator, even as small as 1 mm, could potentially cause significant variations of dose which could result in undesired side effects such as overdose of a critical organ. In this retrospective dosimetric study, the variation of dose due to various small range motions of gynecological applicators is investigated. The results show that the implementation of additional immobilization and localization devices along with other safety measures needs to be further investigated. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection