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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Caracterización cardiopulmonar de la transición feto-neonatal en ovinos (ovis aries) de tierras bajas y del Altiplano Andino

Alegría Vera, René Augusto January 2019 (has links)
Memoria para optar al Título Profesional de Médico Veterinario / Al nacimiento, la transición feto-neonatal involucra importantes cambios cardiorrespiratorios, lo que permite una adaptación eficiente del sistema cardiopulmonar para mantener la vida del neonato. En el Alto Andino, un escenario de hipoxia hipobárica natural, esta transición se ve comprometida debido a la menor disponibilidad de oxígeno, pudiendo generar hipertensión arterial pulmonar del neonato y falla cardíaca derecha. Sin embargo, esta transición cardiopulmonar no ha sido bien caracterizada en la etapa neonatal bajo condiciones de hipoxia crónica. Es por ello, que este estudio tiene por objetivo caracterizar los cambios ecocardiográficos y hemodinámicos de corderos recién nacidos en un periodo de treinta días, tanto en normoxia como en hipoxia hipobárica, el cual permitió determinar por primera vez y de forma no invasiva, los cambios que caracterizan la transición cardiopulmonar de la vida fetal a la neonatal. Al momento de nacer, los ejemplares de tierras altas presentaron disfunción ventricular, caracterizada por una reducción de la fracción de eyección (~23%), engrosamiento gradual del septum interventricular y de la pared del ventriculo derecho (~40%). Además, la arteria pulmonar presentó aumentados índices de resistencia y la relación S/D en tierras altas. En resumen, este estudio ha permitido conocer la función y estructura cardiopulmonar del neonato, abriendo posibilidades predecir resultados con otras especies de interés médico veterinario, estableciendo nuevas metas en el diagnostico cardiológico temprano. / At birth, the fetus-neonatal transition involves important cardiorespiratory changes, allowing an efficient adaptation of the cardiopulmonary system to maintain the life of the newborn. In the Andean Altiplano, a natural hypobaric hypoxia scenario, this transition is compromised due to the lower availability of oxygen, which can generate pulmonary arterial hypertension of the newborn and right heart failure. However, this cardiopulmonary transition has not been well characterized in the neonatal stage. For this reason, this study aimed to characterize the echocardiographic and hemodynamic changes of the newborn lambs in a period of thirty days in both normoxia and hypobaric hypoxia, which allowed for the first time and non-invasively to determine the changes that characterize the transition from fetal to postnatal life. At birth, the highland specimens showed ventricular dysfunction with respect to those of the lowlands, characterized by a reduction in the ejection fraction (~23%), gradual thickening of the interventricular septum and the wall of the right ventricle (~40%). In addition, the pulmonary artery presented increased resistance indices and the S/D ratio at highland. In summary, this study has allowed to know the cardiopulmonary function and structure of the neonate, opening possibilities of predicting results with other species of veterinary medical interest, establishing new goals in the early cardiological diagnosis. / Financiamiento: Proyecto Fondecyt 1151119
152

Premature Rupture of Membranes: A Survey of the Current Clinical Practices of the Maternal-Fetal Medicine Obstetricians in the United States

Nwosu, Uchenna C., Thatcher, Samuel S. 01 January 1993 (has links)
To determine the current clinical practices of perinatologists regarding the management of premature rupture of membranes (PROM), 1,041 perinatologists were surveyed by multiple choice questionnaire with regard to induction of labor, use of antibiotics, tocolytic agents, and corticosteroids following uncomplicated PROM occurring between 19 and 36 weeks. The response rate was 51% (557/ 1,041). There was a consensus on expectant management of preterm PROM, except (1) where fetal lungs are found mature between 33 and 35 weeks gestation (51% induction vs. 44% expectant) and (2) at 19-22 weeks (71% undecided). During the expectant management the majority does not at any time use antibiotics, tocolytic agents, or corticosteroids. No uniform protocol has yet evolved for the management of preterm PROM, especially (1) between 33 and 35 weeks with mature fetal lungs, and (2) at 19-22 weeks gestation.
153

Stillbirth : a psychosocial crisis

Friedlander, Anne January 1986 (has links)
Includes bibliography. / This study is an investigation of the psychosocial trauma of stillbirth and the implications of that trauma for case management. Stillbirth is considered a crisis for parents that calls for immediate intervention and constructive management. It strains family coping mechanisms and can overwhelm them if not properly handled. Additionally, a grief response follows a stillbirth which must be recognised, accepted, and treated therapeutically if needed. Parents' problems and needs have not been adequately met by medical, social or community services. There is also little recognition of the training needed by medical personnel in the management of stillbirths. Stillbirth is also a crisis for medical personnel as the delivery of a dead baby evokes feelings of confusion and stress for those dealing with the confinement and aftercare. By highlighting the psychological and emotional sequelae of stillbirths for parents, the needs of parents after the event, and the needs of personnel providing care, the writer intended to contribute to an improved understanding of the issues related to stillbirth and, ultimately, to more compassionate care for those who experience this unhappy event. Issues analyzed and recorded are as follows: The emotional and physical reactions of mothers following a stillbirth; the assistance that parents need in order to adjust constructively; the impact that the stillbirth has upon the family; the mothers' interpretation of their management in hospital; and the hospital and community services rendered and needed to assist with constructive adjustment. Study data was collected over a six month period. Subjects were selected from one hospital and were residents of the municipal areas of Cape Town. Two face-to-face interviews were conducted with each respondent using a semi-structured interview schedule. The first interview, which took place within a week of the mothers' discharge from hospital, gathered data on the reactions of the respondents to stillbirth, the impact of stillbirth on the family, and respondents' interpretation of their management in hospital. This interview was tape-recorded. The second interview followed the interview schedule and obtained information on the needs of families after a stillbirth. Data was coded on the interview schedules and statistical analysis was done by computer. The findings of this study agreed with previous ones, that mothers display typical grief reactions after a stillbirth. The stillbirth was experienced as a disappointment that caused significant distress for the majority of mothers. Management was found to be satisfactory with the exception of post-natal placement. The need for options in this area became evident. A lack of social and psychological services, both within the hospital and in the community, was found. Using knowledge gained from this study, a support organization for parents experiencing stillbirths has been organized with the writer's assistance. A breakdown in communication between the hospital and the local authority health nursing services, in terms of knowledge about the stillbirth, was apparent, and improvement in this area is needed. Recommended guidelines for management based on the research findings and literature review have been proposed. The role of the social worker, doctor and nursing sister have been outlined.
154

The impact of fetal alcohol syndrome on a child's classroom performance : a case study of a rural South African school

Lubbe, Melissa January 2016 (has links)
Fetal Alcohol Syndrome (FAS) is the most severe of a spectrum of birth defects caused by a mother drinking alcohol whilst pregnant. Its manifestation in the Central Nervous System causes intellectual and behavioural abnormalities, which pose considerable challenges in the classroom. This case study explores the classroom environment and educational outcomes of learners with FAS in a rural South African school. The study was conducted at Elizabethfontein Primary School (EFPS), a farm school near Clanwilliam in the Western Cape. The sample comprises of all 170 learners in Grade 1 to Grade 4. A prevalence rate of FAS of 124 per 1000 (12.4%) was found. EFPS is a Quintile 1 school that relies heavily on fundraising (especially in the form of Riel Dancing) and sponsorship to afford extra staff (such as Koshuis Tannies and teaching assistants), maintenance and transportation of learners. The lack of Grade R school preparation and the environment learners grow up in results in discipline problems, many learners repeating, being progressed before they are ready and a high dropout rate. Child abuse and neglect is common today, prompting the EFPS boarding house to act as "safe haven" during the week for two thirds of its learners. The school provides security, routine and constant meals (as part of the School Nutrition Program and supplemented by the school garden). Data on educational outcomes was collected through participant observation (classroom behaviour), collection of information from existing sauces (Home Language Marks and Mathematics Marks) and collection of new data (Reading Score). A physician diagnosed those children with FAS using a three-stage process. Having FAS is associated with lower home language marks ( 2.8 to 8.55 percentage points) and behavioural scores (1.73 to 4.21 percentage points). The mitigating effect of the school on FAS learners might have reduced the impact of FAS. Children with FAS struggle academically and in following rules and principles as they have lower intellectual capabilities and cannot generalise from one situation to the next. Memory deficits, especially verbally and visuospatially, present challenges in following instructions and copying from the board. Children with FAS are also hyperactive, distractible and inattentive, which causes classroom disruptions and pose a negative externality to other learners. They find it difficult to follow social cues, but want to be helpful and well liked, making children with FAS vulnerable to manipulation. Strategies for intervention have been explored by specialised schools and studies, but must be translated into viable options for the mainstream under-resourced classroom. In order to develop appropriate strategies for classroom intervention a comprehensive understanding of FAS in this context must first be established. Many learners are isolated by a lack of tarred roads and cell phone reception within the large catchment area of EFPS. As descendants of local tribes and slaves the history of this farming area still influences them today. The legacy of the Dop system can still be seen, as alcohol forms a cornerstone of social interactions, especially in binge drinking over weekends, which exposes children to the cycle of alcohol addiction from a young age. Racial segregation and the impact of Apartheid have influenced the educational trajectory of coloured children. The value of this study lies in the in-depth insight into the context learners find themselves in, and the specific challenges associated with FAS learners. Future studies can build on the methodology and explore ways to improve the lives of children with FAS. Research must be interdisciplinary and in collaboration with the community. In response to this research EFPS has declared 2016 as "The Year of Alcohol Awareness" . Intervention strategies must be aimed towards these isolated, under resourced communities.
155

Utero-placental blood flow in hypertensive pregnancy and the effect of nifedipine administration

Lindow, S W January 1987 (has links)
Nifedipine, in a 5mg sublingual acute administration, causes a significant fall in the systolic, diastolic and mean arterial pressure in a mixed group of pregnant hypertensives. A concurrent, significant rise in the pulse rate was seen. The utero-placental blood flow index, which is a measure of utero-placental blood flow, was not significantly reduced following the administration of Nifedipine or a placebo. The utero-placental blood flow index was found to be a consistent measure of utero-placental blood flow in resting patients. In the absence of serious side-effects it can be concluded that Nifedipine is a safe therapy in the acute treatment of hypertensive states in pregnancy.
156

Fetal Alcohol Syndrome

Jaishankar, Gayatri 01 August 1995 (has links)
No description available.
157

Dose and time dependence of alcohol exposure in relation to craniofacial dysmorphisms in fetal alcohol syndrome

Gould, Rebekah January 2013 (has links)
The National Institutes of Health defines Fetal Alcohol Syndrome (FAS) as a debilitating collection of birth defects that include craniofacial dysmorphisms, neurological and motor insufficiencies, growth retardation, and behavioral and social discrepancies. Characteristic craniofacial abnormalities, which include smooth philtrum, thin vermillion border, short palpebral fissures, and microcephaly, are used as a diagnostic tool for FAS. There is agreement across the literature that the characteristic craniofacial dysmorphisms are induced as a result of prenatal alcohol exposure in very specific doses, and during very particular time periods during embryonic development. However, ambiguity still exists about the critical time and dose relationship of prenatal alcohol exposure in the production of FAS. In regards to the critical timing, researchers have concluded that prenatal alcohol exposure during the second half of the first trimester, defined as days 43-94 postconception, was found to cause an increased incidence of smooth philtrum, thin vermillion border, microcephaly and reduced birth weight. Conversely, other studies found that prenatal alcohol exposure on day 7 of gestation in mice, which corresponds to week 3 of human gestation, induced craniofacial abnormalities comparable to those seen in humans with FAS. In regards to the critical dose, there is a linear relationship between the dose of prenatal alcohol exposure and the incidence of FAS-related craniofacial abnormalities, with no safe threshold. It was also found that a binge pattern of drinking was more significantly associated with the craniofacial abnormalities seen in FAS than a continuous or less condensed pattern of drinking, even if the binge pattern involved a smaller absolute dose of alcohol. These results regarding both dose and pattern on prenatal alcohol exposure, suggest that binge-drinking patterns are most significantly associated with craniofacial abnormalities if consumed before pregnancy or during late pregnancy, whereas absolute high doses of alcohol in a non-binge pattern were most significantly associated with craniofacial abnormalities in the first trimester. Further research is required for clarification of the critical time and dose relationships involved in the production of the characteristic craniofacial dysmorphisms seen in FAS. A definite conclusion will aid in the public education and prevention programs for FAS if solid information can be provided about the harms of alcohol consumption during pregnancy in regards to timing and dose.
158

The role of glycation and free radicals in hyperglycemia-induced malformations /

Chan, Ivy January 1994 (has links)
No description available.
159

Reproductive and metabolic programming by exogenous steroids

Connolly, Fiona January 2014 (has links)
Polycystic ovary syndrome (PCOS) is a heterogeneous disorder encompassing reproductive and metabolic phenotypes. Genetic analysis, targeting candidate genes has to date proven unsuccessful in the search for a truly dominant genetic link. Another hypothesis to explain the etiology of PCOS is that of fetal programming in the context of developmental origins of health and disease. Extensive animal studies, validated by human data, support the fetal origins hypothesis of PCOS and highlight that PCOS may arise due to excess androgen exposure in fetal life. Previous reports from our laboratory found metabolic dysfunction in 11 month old prenatally androgenised females (d62-102 of fetal life), which included pancreatic and hepatic alterations. The pancreatic alterations seemed to result from gene expression changes induced in fetal life. Therefore, chapter 3 focuses on the gluconeogenic response in the day 90 fetus following maternal androgenisation from day 62 of gestation. Interestingly hepatic gluconeogenic enzymes, specifically phosphoenolpyruvate caboxykinase (PEPCK) and glucose 6 phosphatase (G6PC), were not altered. However they were decreased in the kidney, in a sex specific manner with PEPCK significantly decreased (P<0.01) and G6PC showing a strong trend toward reduction (P=0.056) in females only. This chapter progresses to explore regulatory pathways involved in gluconeogenic regulation. It seems probable that the female specific increase in circulating testosterone (P<0.001), with increased renal androgen reception (P<0.01), may be accountable for the altered expression of gluconeogenic enzymes in the kidney. Chapter 4 investigates why testosterone concentrations were not increased in the male fetus, after maternal androgenisation, by focusing on the site of testosterone production, the fetal testis. Results demonstrate that the day 90 fetus is capable of responding to prenatal androgenisation by decreasing luteinising hormone (P<0.01) and thus testicular testosterone production, such that there was a global down regulation in steroidogenic enzyme expression, in vivo testosterone production (P<0.001) and Leydig cell morphology was altered (P<0.001). As prenatal androgenisation is administered through the maternal route and placental aromatisation may occur, a novel method whereby the fetus was directly injected was utilised to assess the effects of control oil (C), testosterone (TP) or diethylstilboestrol (DES) on the fetal testis. Unlike DES, direct fetal injection with TP mimics the results found from maternal androgenisation. When the testis are examined at a later date, day 112, ten days after androgen treatment ceases, Leydig cell morphology and steroidogenic gene expression return to control values, although fascinatingly, an overshoot of in vivo testosterone production (P<0.01) was observed. When the maternal androgenisation window is extended to begin at day 30 of fetal life, further changes are noted including increased circulating testosterone (P<0.01), a strong trend toward decreased testis weight (P=0.0519) and altered expression of Sertoli and germ cell specific markers. These studies are followed up by assessing the legacy effect of testosterone on the peripubertal male testis in Chapter 5. At ten weeks of postnatal life, males, exposed to androgens from day 62-102 of fetal life had reduced testis weight (P<0.05). However, functional or cellular alterations were not observed and by 12 weeks of age, when LH had normalised, testicular weight and stimulated testosterone secretion of prenatally TP-treated males was comparable to controls. This highlights the remarkable plasticity of the testis and the unremarkable legacy of altered prenatal androgen exposure. The legacy effect of testosterone on the fetal ovary is examined in Chapter 6. Previous studies from our laboratory found minor functional alterations but no structural alterations in the fetal ovary at day 90 following androgenisation from day 62. However, as this was at a time of a highly androgenic environment we assessed the function and morphology of the ovary ten days after the removal of testosterone at day 112. In marked contrast to the normalisation of the male gonad, we observe structural changes with an increase in recruited follicles from the primordial to primary stage in the testosterone treated group (P<0.01). The chapter continues with an investigation of pathways involved in the altered follicular dynamics that may account for the change in follicular recruitment. Furthermore, the functional changes which were previously noted in the day 90 ovary were also examined in response to direct exogenous steroid treatment including, C, TP, DES and dexamethasone (DEX) and also when the window of maternal androgenisation was extended to begin at day 30. Interesting changes are observed such that the direct fetal injection treatments induce similar changes to each other, regardless of the steroid, whilst maternal androgenisation induces a different response. This highlights the complexity of the pathways involved in female gonadal development.
160

Factibilidade e reprodutibilidade da avaliação da restrição de difusão de água por meio da ressonância magnética no cérebro do feto na síndrome de transfusão feto-fetal : Feasibility and reproducibility of diffusion-weighted magnetic resonance imaging of the fetal brain in twin-twin transfusion syndrome / Feasibility and reproducibility of diffusion-weighted magnetic resonance imaging of the fetal brain in twin-twin transfusion syndrome

Santos Neto, Orlando Gomes dos, 1976- 27 November 2018 (has links)
Orientador: Cleisson Fábio Andrioli Peralta / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-11-27T11:52:28Z (GMT). No. of bitstreams: 1 SantosNeto_OrlandoGomesdos_M.pdf: 1132176 bytes, checksum: d5202b7fe95c1aed116aef2fa03d7e3b (MD5) Previous issue date: 2013 / Resumo: Introdução: As lesões neurológicas fetais são importante causa de morbimortalidade neonatal. Uma condição relativamente frequente que expõe os fetos a maior risco de lesão cerebral é a síndrome da transfusão feto-fetal grave (STFF). O tratamento de escolha para STFF consiste na ablação dos vasos placentários com laser (AVPL) e mesmo após a sua realização existe possibilidade de lesão neurológica fetal. A ultrassonografia (USG) é ainda o método de escolha para a avaliação de anormalidades encefálicas fetais, e a ressonância magnética (RNM) pode melhorar o diagnóstico em condições específicas. Entretanto, a USG e as imagens ponderadas T1 e T2 da RM não são apropriadas para a detecção de lesões isquêmicas. A Restrição de Difusão da ressonância magnética (RD-RNM) permite a detecção de eventos isquêmicos agudos no cérebro através da avaliação subjetiva e objetiva da difusão microscópica da água. Esta última pode ser obtida por meio da medida do coeficiente de difusão aparente (CDA) e sua reprodutibilidade no cérebro fetal normal, em gestações únicas, foi recentemente demonstrada. Objetivo: Testar a factibilidade e a reprodutibilidade da restrição de difusão da ressonância magnética nas avaliações do cérebro fetal em casos de síndrome de transfusão feto-fetal tratados com a ablação dos vasos placentários com laser. Materiais e Métodos: Este estudo foi realizado no período de maio de 2011 a junho de 2012, após aprovação pelo Comitê de Ética em Pesquisa da FCM/UNICAMP. Pacientes com STFF grave realizaram uma ressonância magnética para a avaliação do cérebro dos fetos antes e depois da AVPL. Os dados foram analisados off-line em imagens axiais da restrição de difusão (RD) e em mapas do coeficiente de difusão aparente por dois radiologistas. A avaliação subjetiva foi descrita como a ausência ou a presença de restrição de difusão da água. A avaliação objetiva foi realizada através da colocação de regiões de interesse circulares de 20 mm2 nas imagens de RD e em mapas de CDA. A concordância subjetiva inter observadores foi avaliada pelo coeficiente de correlação de Kappa. As medidas do CDA realizadas pelo mesmo observador e por observadores diferentes foram comparadas por meio de testes de Bland-Altman proporcionais. Resultados: As análises foram realizadas em 23 pacientes (46 fetos) com STFF grave, antes e após a AVPL, totalizando noventa e dois exames RD-RNM. Destes, 62 (67%) foram considerados de boa qualidade para avaliação. A concordância entre os radiologistas foi de 100% tanto para a ausência (55/62 = 89%) quanto para a presença (7/62=11%) de restrição de difusão da água. Com relação às concordâncias intra e inter-observadores das medidas do CDA, o teste de Bland-Altman mostrou diferenças percentuais médias de menos de 1,5% e Intervalo de Confiança (IC) de 95% em menos de 18% em todos os locais avaliados. Conclusões: Nossos dados sugerem que a avaliação RD-RNM do cérebro fetal em STFF é factível e reprodutível. Este método pode representar uma ferramenta útil para o aconselhamento dos pais sobre a evolução neurológica de seus filhos / Abstract: Introduction: The fetal neurological injuries are an important cause of neonatal morbidity and mortality. Severe twin-twin transfusion syndrome (TTTS) is a relatively frequent condition that exposes the fetuses to a higher risk of brain injury. The treatment of choice for TTTS consists in laser ablation of placental vessels (LAPV) and even after its completion there is the possibility of fetal neurologic injury. Ultrasonography (USG) is still the method of choice for evaluation of fetal brain abnormalities, and magnetic resonance imaging (MRI) can improve the diagnostic in specific conditions. However, ultrasonography and the T1 and T2 weighted images of MRI are not suitable for detection of ischemic lesions. Diffusion-weighted (DW) MRI enables the detection of acute hypoxic-ischemic events in the brain through subjective and objective evaluation of the microscopic diffusion of water. An objective evaluation consists of measuring the apparent diffusion coefficient (ADC): the reproducibility of this method in the normal fetal brain in singleton pregnancies was recently demonstrated. Purpose: To test the feasibility and reproducibility of diffusion-weighted magnetic resonance imaging (DW-MRI) evaluations of fetal brains in cases of twin-twin transfusion syndrome treated with laser ablation of placental vessels. Materials and Methods: This study was conducted from May 2011 to June 2012, after approval by the Institutional Review Board of FCM/UNICAMP. Patients with severe TTTS received an MRI scan for the evaluation of fetal brain before and after LAPV. Datasets were analyzed offline on axial DW images and apparent diffusion coefficient (ADC) maps by two radiologists. The subjective evaluation was described as the absence or presence of water diffusion restriction. The objective evaluation was performed by the placement of 20-mm2 circular regions of interest on the DW image and ADC maps. Subjective inter-observer agreement was assessed by the Kappa correlation coefficient. ADC measurements performed by the same observer and by different observers were compared using proportionate Bland-Altman tests. Results: Analyses were performed in 23 patients (46 fetuses) with severe TTTS before and after LAVP totaling 92 examinations RD-RM. Of these, 62 (67%) were of good quality for evaluation. The agreement between radiologists was 100% in the absent (55/62 = 89%) and in the presence (7/62 = 11%) of restricted diffusion of water. With respect to intra and inter-observer measurements of the ADC, the Bland-Altman plots showed average percentage differences of less than 1.5% and Confidence Interval (CI) of 95% in less than 18% in all regions evaluated. Conclusions: Our data suggest that DW-MRI evaluation of the fetal brain in TTTS is feasible and reproducible. This method may represent a useful tool for counseling parents about the neurological outcome of their infants / Mestrado / Saúde Materna e Perinatal / Mestre em Tocoginecologia

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