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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.
401

Crescimento fetal, tamanho ao nascer e problema de saúde mental aos 11 anos: estudo de coorte de nascimentos de 1993, Pelotas - RS / Fetal growth, birth size and mental health problems at 11 years of age: the 1993 Pelotas (Brazil) births cohort study

Gallo, Erika Alejandra Giraldo 04 November 2010 (has links)
Made available in DSpace on 2014-08-20T13:57:55Z (GMT). No. of bitstreams: 1 Dissertacao_Erika_Alejandra_Giraldo_Gallo.pdf: 1240790 bytes, checksum: e1c81f5b6b4450551bde3768d0565387 (MD5) Previous issue date: 2010-11-04 / The aim of this study was to evaluate the association between fetal growth and size at birth with mental health problems at 11 years of age in the 1993 Pelotas (Brazil) Birth Cohort Study. Newborns were weighed and measured and calculated anthropometric indexes. At age 11, were assessed mental health problems with the strengths and difficulties questionnaire (SDQ). The prevalence of mental health problems was 32%. After adjustment for potential confounders, we found that newborns with the z score of weight for age and body mass index (BMI) for age <-2 SD were respectively 27% (95% CI: 7to 49) and 29% (95% CI: 10 to 51) greater risk of developing mental health problems at age 11 than born with normal scores. Newborns with BMI z score for age and head circumference > +2 SD were respectively 34% (95% CI: 6 to 71) and 19% (95% : 1 to 40) greater risk of developing the disease than babies with normal scores. The results suggest that factors occurring during pregnancy that are reflected in measures of size at birth can cause mental health problems in late stages. / O objetivo deste estudo foi avaliar a associação entre crescimento fetal e tamanho ao nascer com problemas de saúde mental aos 11 anos na Coorte de Nascimentos de 1993 de Pelotas, RS. Recém-nascidos foram pesados e medidos, e calculados índices antropométricos. Aos 11 anos, foram avaliados problemas de saúde mental com o questionário de capacidades e dificuldades (SDQ). A prevalência de problemas de saúde mental foi 32%. Após ajuste para fatores de confusão, recém-nascidos com escore z de peso/idade e índice de massa corporal (IMC)/idade <-2 DP apresentaram respectivamente 27% (IC95%: 7 a 21) e 29% (IC95%: 10 a 51) maior risco de desenvolver problemas de saúde mental aos 11 anos que nascidos com escore normal. Recém-nascidos com escore z de IMC/idade e perímetro cefálico >+2 DP apresentaram respectivamente 34% (IC95%: 6 a 71) e 19% (IC95%: 1 a 40) maior risco de desenvolver estes problemas que nascidos com escore normal. Os resultados sugerem que fatores ocorridos na gestação e refletidos nas medidas de tamanho ao nascer podem ocasionar problemas de saúde mental em etapas tardias.
402

Fatores de risco maternos para morte fetal: um estudo de casos e controles de base populacional / Maternal risk factors for fetal death: a case-control study of a population-based

Manitto, Alicia Matijasevich 19 April 2005 (has links)
Made available in DSpace on 2014-08-20T13:57:57Z (GMT). No. of bitstreams: 1 Tese_Alicia_Matijasevich_Manitto.pdf: 2913108 bytes, checksum: 78680a724fa7ab0a5d31a434a6e8cf3f (MD5) Previous issue date: 2005-04-19 / The aim of this study was to evaluate the available epidemiological evidence of the effect of caffeine consumption during pregnancy on fetal mortality. A systematic qualitative review of observational studies that referred to any source of exposure to caffeine from food in pregnancy and to fetal mortality as the outcome was conducted at the electronic databases Medline and Lilacs. Studies published between January 1966 and September 2004 were searched. The following descriptors were used: caffeine , coffee , tea , cola and cacao to define the exposure and fetal death , stillbirth , fetal demise and fetal loss to define the outcome. A total of four publications were found. The small number of publications addressing this subject, methodological limitations, inaccurate exposure assessment in all the studies, overall risks only marginally significant in most cases and the possibility of publication bias prevent to state with certainty that caffeine consumption is actually associated with fetal death. Well-designed future research with further assessment of caffeine intake is needed to define the role of caffeine in fetal mortality. / O objetivo deste estudo foi avaliar a evidência epidemiológica do efeito do consumo de cafeína durante a gravidez sobre a mortalidade fetal. Uma revisão sistemática qualitativa de estudos observacionais que se refere a qualquer fonte de exposição a cafeína de alimentos na gravidez e para a mortalidade fetal como o resultado foi conduzido na eletrônica bases de dados Medline e Lilacs. Estudos publicados entre janeiro de 1966 e setembro de 2004. Os descritores utilizados foram: "cafeína", "café", "chá", "cola" e "cacau" para definir a exposição e "morte fetal", "natimorto", "morte fetal" e "perda fetal" para definir o resultado. Um total de quatro publicações foram encontradas. O pequeno número de publicações que tratam desse assunto, as limitações metodológicas, a avaliação da exposição imprecisa em todos os estudos, os riscos marginalmente significativas na maioria dos casos e a possibilidade de viés de publicação evitar afirmar com certeza que o consumo de cafeína é associado a morte fetal. Bem concebido futuras pesquisas com uma nova avaliação de ingestão de cafeína é necessário para definir o papel da cafeína na mortalidade fetal.
403

Type XIII collagen: regulation of cardiovascular development and malignant transformation in transgenic mice

Sund, M. (Malin) 13 November 2001 (has links)
Abstract Type XIII collagen is a type II oriented transmembrane protein with a short intracellular domain, a single transmembrane domain and a large, mostly collagenous extracellular domain. Tissue localization and cell culture studies have implicated that it is involved in cell adhesion. The spatio-temporal expression of type XIII collagen mRNA and protein during murine development is studied here. Type XIII collagen mRNAs were expressed at a constant rate during development, with an increase of expression towards birth. The strongest expression was detected in the central and peripheral nervous systems of the developing mouse fetus. Cultured primary neurons expressed this collagen, and recombinant type XIII collagen was found to enhance neurite outgrowth. Strong expression was also detected in the heart, with localization to cell-cell contacts and perinatal accentuation in the intercalated discs. Other sites of type XIII collagen expression included cartilage, bone, skeletal muscle, lung, intestine and skin. Clear developmental shifts in expression suggest a role in endochondral ossification of bone and the branching morphogenesis in the lung. To elucidate the function of type XIII collagen transgenic mice were generated by microinjection of a cDNA construct that directs the synthesis of truncated α1(XIII) chains with an in-frame deletion of the central collagenous COL2 domain. This construct was thought to disrupt the assembly of normal type XIII collagen trimers. Expression of shortened α1(XIII) chains by fibroblasts derived from mutant mice was demonstrated, and the lack of intracellular accumulation in immunohistochemical analysis of tissues suggested that the mutant molecules were expressed on the cell surface. Transgene expression led to developmental arrest and fetal mortality in offspring from heterozygous mating with two distinct phenotypes. The early phenotype fetuses were aborted by day 10.5 of development due to a failure in the fusion of the chorion and allantois membranes and subsequent disruption in placentation, while the late phenotype fetuses were aborted by day 13.5 of development due to cardiovascular and placental defects. Furthermore, it was shown that the heterozygous mice that were initially of normal appearance and bred normally had an increased susceptibility to develop T-cell lymphomas and angiosarcomas later in life. The results presented here increase the evidence that type XIII collagen is involved in cell adhesion, with several important tasks during development. A role of type XIII collagen in malignant transformation of certain mesenchymal cell populations is also implicated.
404

Placental insufficiency and fetal heart: Doppler ultrasonographic and biochemical markers of fetal cardiac dysfunction

Mäkikallio, K. (Kaarin) 28 July 2002 (has links)
Abstract The first aim of this study was to investigate the relationship between Doppler ultrasonographic parameters and biochemical markers of human fetal cardiac dysfunction and myocardial cell damage in pregnancies complicated by placental insufficiency and/or fetal growth restriction. Our second aim was to examine fetal central and peripheral hemodynamic characteristics associated with retrograde aortic isthmus net blood flow. Fetuses with significant myocardial cell damage (cTnT > 0.10 ng/ml) had increased pulsatility in the blood velocity waveforms of ductus venosus, left hepatic vein and inferior vena cava, and had more often atrial pulsations in the umbilical vein. Their umbilical artery NT-proANP concentrations were higher than in fetuses without myocardial cell damage. The proportion of left ventricular cardiac output of the combined cardiac output was greater and the corresponding proportion of the right ventricle was less than in fetuses with only increased NT-proANP levels ( > 1145 pmol/l). Tricuspid regurgitation was present more often and the right ventricular fractional shortening was less in fetuses with myocardial cell damage than in fetuses with normal umbilical artery cTnT levels. In fetuses with placental insufficiency and/or growth restriction (n = 48), umbilical artery NT-proANP concentrations showed a significant positive correlation with ductus venosus, left hepatic vein and inferior vena cava pulsatility index values for veins. Fetuses with placental insufficiency and antegrade aortic isthmus net blood flow demonstrated a shift in their right ventricular cardiac output from the pulmonary to the systemic circulation, and foramen ovale volume blood flow made up the majority of the left ventricular cardiac output. Fetuses with retrograde aortic isthmus net blood flow failed to demonstrate these changes, and they had signs of increased left atrial pressure. In addition, right ventricular fractional shortening was decreased and the pulsatility in the ductus venosus blood velocity waveforms was increased. In conclusion, human fetal myocardial cell damage was associated with a rise in systemic venous pressure, a change in the distribution of cardiac output towards the left ventricle and a rise in right ventricular afterload. Fetuses with retrograde aortic isthmus net blood flow failed to rearrange the distribution of the cardiac output and they had signs of increased left atrial pressure. In addition, right ventricular afterload and pulsatility in the ductus venosus blood velocity waveforms were increased.
405

Erbjuda undersökning - För kvinnans, fostrets eller barnmorskans skull : En intervjustudie kring barnmorskors erfarenheter av telefonrådgivning vid minskade fosterrörelser / Offer Examination - For the woman, the fetus or midwife's sake : An interview study on midwives' experiences on telephone counseling in case of reduced fetal movements.

Lindgren, Zandra, Sundqvist, Ronja January 2017 (has links)
Bakgrund: Fosterrörelserna ses som ett friskhetstecken. Fostrets rörelser ändrar karaktär under graviditeten, men det är en myt att de ofta blir svagare i slutet av graviditeten. Minskade fosterrörelser är ett viktigt kliniskt tecken som kan föregå intrauterin fosterdöd (IUFD). Kvinnan tar telefonkontakt när hon är orolig då hon upplever ett ändrat rörelsemönster. Socialstyrelsens nya riktlinjer finns till för korrekt handläggning, undersökning utan fördröjning kan förebygga livshotande tillstånd hos fostret. Syftet var att beskriva barnmorskors erfarenheter av telefonrådgivning till gravida som kontaktar förlossningsavdelningen gällande minskade fosterrörelser.Design: Studien har utgått ifrån en kvalitativ design med deskriptiv ansats. Datainsamlingen utfördes med semistrukturerade intervjuer och analyserades med kvalitativ innehållsanalys.Deltagare och omgivning: Tio barnmorskor som arbetade vid en förlossningsavdelning i norra Sverige.Resultat: I studien framkom två huvudkategorier, försöka bemöta oron samt komma till ett beslut och sju kategorier. Barnmorskorna är medvetna om vilka riskfaktorer som föreligger för minskade fosterrörelser och IUFD samt kring andra faktorer som kan ha betydelse för fosterrörelserna. Barnmorskorna ger “handgripliga” råd till kvinnan innan hon återkommer och i vissa fall erbjuds undersökning direkt. Telefonrådgivning förekommer dagligen och barnmorskorna belyser vikten av att vara lyhörd och ta kvinnans oro på allvar. Det ses som svårt att bedöma fostrets välmående över telefonen. Kommunikationen och erfarenhetsutbyte mellan kollegor anses värdefullt, men det upplevs även som en svårighet att ta del av nya riktlinjer på kliniken. Slutsats: Telefonrådgivningen är en komplex uppgift där en korrekt handläggning som grundar sig på evidens är avgörande för fostrets överlevnad. Riktlinjer och PM måste utformas för att barnmorskorna ska kunna handlägga minskade fosterrörelser på likartat sätt. Kliniska implikationer: Gravida kvinnor bör få information om fosterrörelser på mödravården för att öka medvetenheten. Ett nationellt utformat PM för rådgivning vid minskade fosterrörelser bör upprättas för kvinnors lika vård på lika villkor. Ökad medvetenhet hos vårdgivare om att undvika avvaktande råd då dessa saknar evidens. Nyckelord: Barnmorska, minskade fosterrörelser, IUFD, telefonrådgivning, rådgivning
406

Assessing and quantifying placental dysfunction in relation to pregnancy outcome in pregnancies complicated by reduced fetal movements

Higgins, Lucy January 2015 (has links)
Currently there is no test to accurately predict stillbirth. It is proposed that better identification of placental disease in utero may aid stillbirth prediction and prevention. Pregnancies complicated by reduced fetal movement (RFM) have increased risk of stillbirth. We hypothesised that RFM is a symptom of placental dysfunction associated with adverse pregnancy outcome (APO) and that this placental abnormality can be detected antenatally and used to identify fetuses at highest-risk of APO. We tested this hypothesis by: 1) comparison of ex vivo placental structure and function between APO RFM pregnancies and their normal outcome RFM counterparts, 2) comparison of in utero estimates of placental size, vascularity, vascular and endocrine functions obtained from placental ultrasound, Doppler waveform analysis and maternal circulating placentally-derived hormone concentrations, to their ex vivo correlates and 3) examination of the predictive potential of placental biomarkers at the time of RFM.Ex vivo placentas from APO RFM pregnancies, compared to normal outcome RFM counterparts, were smaller (diameter, area, weight and volume, p<0.0001), less vascular (vessel number and density, p≤0.002), with arteries that were less responsive to sodium nitroprusside (p<0.05), and with aberrant endocrine function (reduced tissue content and/or release of human chorionic gonadotrophin (hCG), human placental lactogen (hPL) and soluble fms-like Tyrosine Kinase-1 (sFlt-1), p<0.03). Placental volume (PV) ex vivo correlated with sonographic estimated PV (p<0.004), hPL, hCG and placental growth factor (PlGF) concentrations in the maternal circulation (p<0.03). Ex vivo villous vessel number and density correlated with Doppler impedance at the umbilical artery free-loop (UAD-F, p=0.02) and intraplacental arteries (p<0.0001) respectively, whilst UAD-F impedance correlated with arterial thromboxane sensitivity (p<0.04). Examination of placental structure and function at the time of presentation with RFM identified 15 independently-predictive biomarkers. Three potential predictive models, incorporating measures of placental size (PlGF), endocrine function (sFlt-1), arterial thromboxane sensitivity and villous vascularity (UAD-F), were proposed. Using these models, sensitivity for APO was improved from 8.9% with baseline care (assessment of fetal size and gestation) to up to 37.5% at a fixed specificity of 99% (p<0.05). This series of studies shows that antenatal placental examination is possible and improves identification of pregnancies at highest risk of stillbirth in a high-risk population by up to 29%. Therefore such tests merit further development to prospectively assess their ability to predict and prevent stillbirth itself.
407

Prolactine placentaire et anomalies de croissance au cours du diabète maternel / Placental prolactin and growth disorders during maternal diabetes

Perimenis, Pierrette 20 September 2014 (has links)
Malgré l’amélioration des prises en charge diabétologiques et obstétricales, la grossesse chez la patiente ayant un diabète pré-gestationnel ou gestationnel reste à ce jour à haut risque pour la mère et pour l’enfant. Chez l’enfant, les anomalies de croissance, macrosomie, mais parfois Retard de Croissance Intra-Utérin (RCIU) restent à ce jour très fréquentes avec des conséquences à court et à long terme. La croissance fœtale est un processus complexe mettant en jeu la susceptibilité génétique fœtale mais surtout le milieu intra-utérin à savoir l’environnement métabolique maternel et placentaire. Les mécanismes physiopathologiques en lien avec ces anomalies de croissance dans ce contexte de diabète restent encore incompris et mal expliqués par l’hyperglycémie maternelle seule. A l’interface entre la mère et le fœtus, le placenta exerce plusieurs fonctions influençant le métabolisme maternel et fœto-placentaire donc le développement de l’unité fœto-placentaire. Le placenta, acteur crucial de la programmation fœtale, va s’adapter à son environnement afin de permettre la survie fœtale.L’objectif de ce travail de thèse était d’étudier le compartiment placentaire en analysant l’expression des gènes impliqués dans la croissance fœto-placentaire afin de déterminer des facteurs prédictifs des anomalies de croissance au cours du diabète maternel. Pour répondre à cet objectif, nous avons d'abord utilisé un modèle de rate gestante rendue diabétique par la streptozotocine seule ou associée avec la nicotinamide et validé certains de nos résultats dans des placentas issus de patientes diabétiques de type 1. L’analyse du transcriptome placentaire a mis en évidence l’implication prépondérante de certains gènes appartenant à la famille prolactine (PRL), au système rénine-angiotensine et aux métalloprotéases. La caractéristique phénotypique de ces ratons était de présenter un RCIU à la naissance avec sur le plan histologique une hypovascularisation placentaire associée.Nous nous sommes surtout intéressés aux gènes placentaires appartenant à la famille PRL, non décrits auparavant dans la littérature dans le diabète, comme prl8a2, connu aussi sous le nom de Dprp (Decidual Prolactin Related-Protein). La PRL dans sa forme native de 23-kDa a des propriétés pro-angiogéniques alors que clivée en vasoinhibines par la Bone morphogenetic protein1 (BMP1), la cathepsine D, a des propriétés anti-angiogéniques. Chez nos 2 modèles de rates, nous confirmons une surexpression par qPCR de Dprp, et de Bmp1 et une augmentation du rapport du clivage de la PRL et donc des vasoinhibines par rapport aux contrôles.Nous avons pu valider ces résultats dans des placentas de patientes diabétiques de type 1 dont la caractéristique chez les nouveaux nés était un petit poids de naissance. Enfin, nous nous sommes intéressés à la cinétique de ces anomalies concernant la famille PRL dans nos modèles animaux. Nous avons pu montrer chez la rate gestante diabétique que le RCIU était présent dès le 14ème jour de gestation et que la quantité en vasoinhibines et l’expression des gènes Bmp1 et Dprp n'étaient modifiées qu'à partir du 17ème jour de gestation.Ces travaux sont en faveur d’une implication de la PRL placentaire et de ses vasoinhibines dans le diabète maternel laissant leur supposer un rôle dans l’hypovascularisation placentaire, mise en évidence à la fois chez l'homme et l'animal. En perspective, nous envisageons de poursuivre ces travaux avec une approche plus fonctionnelle. Il convient de préciser l’implication de la BMP1 en confirmant sa responsabilité dans le clivage de la PRL, en analysant plus finement la relation entre vasoinhibines et hyperglycémie en tenant compte du degré et de la durée d’exposition de l'hyperglycémie. Enfin, il serait intéressant de regarder l’implication de la PRL placentaire non plus au cours du RCIU mais plutôt au cours de la macrosomie fœtale, qui reste l’anomalie de croissance la plus fréquente au cours du diabète maternel. / Despite the improvement of obstetrical and diabetological care, the pregnancy of the patient presenting a gestational or pregestational diabetes remains ourdays at a high risk for the mother and for its child. For the child, fetal growth disorders such as macrosomia but also intra-uterine growth restriction (IUGR) are still very frequent with short and long-term consequences. Fetal growth is a complex process involving the fetal genetic susceptibility but also the intra-uterine environment especially in its maternal and placental metabolic aspects. The link between the physiopathological mechanisms of these disorders and fetal growth in this context of maternal diabetes remains unclear and partially explained by maternal hyperglycemia only. At an interface between the mother and the fetus, the placenta employes multiples functions that influence maternal, fetal and placental metabolisms and consequently the fetoplacental unit development. The placenta, as crucial actor of fetal programming, must adapt to its environnment for the survival of the fetus.The objectives of this thesis were to study the placental compartment with an analysis of expression of genes involved in feto-placental growth to determine the predictive factors of these growth disorders during maternal diabetes. To bring a response to these objectives, we used initially a model of gestant rat diabetes induced by streptozotocin alone or in combination with nicotinamide and we validated some of our results in the placenta from type 1 diabetic mothers.The placental transcriptomic analysis pointed out the involvment of some genes of the prolactin (PRL) family, of the renine-angiotensin-aldosterone system and of metalloproteinase family. The principal phenotypical characteristic of the pups at birth was an IUGR with an histological aspect of a placental hypovascularization associated.We focused especially to the placental genes of the PRL familly, non described before in the litterature in diabetes, such as prl8a2 also known as Dprp (decidual prolactin related-protein). PRL in its native form of 23 kDa is proangiogenic but when processed by Bone morphogenetic protein 1 (BMP-1) or cathepsin D (CTSD) to vasoinhibins has antiangiogenic properties. In our 2 rat models, we demonstrated by qPCR an upregulation of Bmp-1 and Dprp with an increase amount of vasoinhibins when compared to controls.We could validate some of our results in the placenta from diabetic type 1 women with a characteristic of small birth weight of the newborns.Finally, we interested in the course of these disorders concerning PRL family in our animal models during their pregnancy. We could demonstrate that IUGR was present by 14th day of gestation. Bmp-1 or Dprp gene expression and the vasoinhibin amount were not different between groups at the 14th day of gestation but modified by 17th day of gestation.These studies highlighted a placental involvment of PRL and its vasoinhibins during maternal diabetes suggesting a role in placental hypovascularisation in animal and women.The perspectives will be in continuing these studies with a more functional approach. We have to bring more details about the involvment of BMP-1 in this PRL process with an in-depth analysis of the link between hyperglycemia and vasoinhibins among the degree and the time of exposition to hyperglycemia. Finally, it would be interesting to study the involvment of placental PRL not only in the cases of IUGR but also in that of macrosomia, that remains the most frequent fetal growth disorder during maternal diabetes.
408

Efeito do manejo nutricional sobre a maturação do eixo reprodutivo somatotrófico no início da puberdade de novilhas Nelore / Effect of nutrient management on the maturation of the reproductive axis in somatotrophic onset of puberty in heifers Nellore

Delci de Deus Nepomuceno 10 December 2012 (has links)
Objetivou-se no presente estudo, avaliar o efeito da nutrição proteica no terço final da gestação de vacas Nelore, seguido de estratégias de suplementação e/ou alimentação de suas crias fêmeas sobre a idade à puberdade até os 18 meses. O delineamento utilizado foi o inteiramente casualizado em esquema fatorial 2x2x2; constituindo-se de: 2 manejos suplementar das vacas no pré-parto (Fase I); 2 manejos suplementar das crias (Fase II) e 2 manejos alimentar na recria (Fase IIIA). Na Fase I, 241 vacas foram suplementadas com farelos de soja na proporção de 0,5kg/vaca/dia (Tratamento 1) e 258 vacas foram mantidas sem acesso a suplementação Tratamento 2 (controle - Fase I). Cerca de metade do número de vacas e suas crias fêmeas, nascidas na Fase I, foram distribuídas em dois tratamentos na Fase II-(suplementação das crias) aos 110 dias de idade das crias, as quais passaram receber ou não uma mistura mineral proteica energética em creep-feeding, constituindo assim, os tratamentos suplementação de bezerras em creep-feeding (n =119) e controle (sem suplementação, n =122 ) na Fase II até os 205 dias de idade (desmama). Na fase III A, metade das bezerras de cada grupo na fase II foram manejados em confinamentos (n=119) e a outra metade permaneceu no pasto (Grupo controle, n = 122), até os 320 dias de idade. Na fase IIIB, todas as novilhas foram manejados juntos a pasto e submetidas a estação de monta a partir dos 440 dias aos 560 dias de idade. Os sistemas de suplementação das vacas e bezerras na fase de cria não afetaram o peso corporal, concentração de IGF-1 e percentual de peso adulto das novilhas no início da estação de monta (P > 0,05). O manejo das novilhas em confinamento na fase IIIA, aumentou o número de novilhas púberes (31,9% vs 13,9%; P < 0,01), para as novilhas alimentadas ou não em confinamento, respectivamente. Entretanto, a alimentação em confinamento não ocasionou diferença na idade que estas atingiram a puberdade. Considerando apenas as novilhas que atingiram à puberdade (n = 55) houve efeito de interação entre as fases de suplementação/alimentação e a idade à puberdade (P < 0,05). Para as vacas manejadas na Fase I, a suplementação influenciou a ciclicidade das mesmas no momento da IATF (68,9% vs 55,4%; P < 0,05), porém não ocasionou diferença no número de vacas prenhes (60,1 vs 55,3%; P > 0,05), vacas suplementadas e não suplementadas, respectivamente. Similarmente, a suplementação das novilhas em creep-feeding, não influenciou a taxa de prenhez das vacas (P > 0,05). Em conclusão, a suplementação das vacas com fontes proteicas não influenciou a idade a puberdade de novilhas até os 18 meses, sendo que o manejo alimentar em confinamento aumentou o número de novilhas púberes em relação com as manejadas no pasto. / The aim of the present study was to evaluate the effect of protein nutrition in the final third of gestation of Nelore cows, followed by supplementation strategies and / or feed their young females over the age of puberty until 18 months. The experimental design was a completely randomized factorial 2x2x2; constituting of: 2 suplementary managements of cows in pre-partum (Phase I); 2 supplementary managements of offspring (Phase II) and 2 alimentary managements during rearing (Phase IIIA). In Phase I, 241 cows were supplemented with soybean meal at the rate of 0.5 kg / cow / day (Treatment 1) and 258 cows were kept without access to supplemental Treatment 2 (control - phase I). About half of the cows and their female offspring, born in Phase I, were assigned to two treatments in Phase-II (supplementation of cubs) at 110 days of age of the offsprings, which now receive or not a mineral mix protein energy in creep-feeding, constituting, treatments supplementation in calves creep-feeding (n = 119) and control group (without supplementation, n = 122) in Phase II until 205 days of age (weaning). In phase III A, half of each group of calves in phase II were managed in feedlots (n = 119) and the other half remained in the pasture (control group, n = 122), up to 320 days of age. In stage IIIB, all heifers were managed together and submitted to the pasture breeding season from 440 days to 560 days old. Supplementation systems of cows and calves during the growing period did not affect body weight, concentration of IGF-1 and percentage of mature weight of heifers at the beginning of the breeding season (P> 0.05). The management of heifers in the feedlot phase IIIA, increased the number of pubertal heifers (31.9% vs 13.9%, P <0.01) for heifers fed in confinement or not, respectively. However, feeding in confinement caused no difference in age they reached puberty. Considering only heifers reached puberty (n = 55) there was an interaction effect between phases of supplementation / nutrition and age at puberty (P <0.05). For cows managed in Phase I, supplementation influenced the cyclicality of the same at the time of TAI (68.9% vs 55.4%, P <0.05), but caused no difference in the number of pregnant cows (60.1 vs 55.3%, P> 0.05), supplemented and nonsupplemented cows, respectively. Similarly, the addition of heifers in creep-feeding did not influence the rate of pregnancy in cows (P> 0.05). In conclusion, supplementation of cows with protein sources did not influence the age at puberty in heifers up to 18 months, and feeding management in confinement increased the number of pubertal compared with those managed on pasture.
409

Human and Social Dimensions That Arose with the Early Cases of Fetal Surgery to Correct Myelomeningocele

January 2020 (has links)
abstract: This thesis reviews the initial cases of fetal surgery to correct myelomeningocele, a severe form of spina bifida, and discusses the human and social dimensions of the procedure. Myelomeningocele is a fetal anomaly that forms from improper closure of the spinal cord and the tissues that surround it. Physicians perform fetal surgery on a developing fetus, while it is in the womb, to mitigate its impacts. Fetal surgery to correct this condition was first performed experimentally in the mid-1990and as of 2020, it is commonly performed. The initial cases illuminated important human and social dimensions of the technique, including physical risks, psychological dimensions, physician bias, and religious convictions, which affect decision-making concerning this fetal surgery. Enduring questions remain in 2020. The driving question for this thesis is: given those human and social dimensions that surround fetal surgery to correct myelomeningocele, whether and when is the surgery justified? This thesis shows that more research is needed to answer or clarify this question. / Dissertation/Thesis / Masters Thesis Biology 2020
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The role of teratogen exposure on neural crest cells in the pathogenesis of fetal alcohol spectrum disorders

Carozza, Richard Bohling 03 November 2015 (has links)
Maternal consumption of ethanol during pregnancy contributes to a set of pathologies, grouped together as the fetal alcohol spectrum disorders, affecting as many as 5% of live births in the United States annually. Ethanol acts widely in the developing embryo, affecting many tissues, but causing deficits in neuronal and neural crest populations particularly. These deleterious effects cause archetypical craniofacial expression and neurological deficits, including microcephaly and neuronal dysfunction. Severity of symptoms is linked to frequency of maternal alcohol consumption as well as the maximum blood alcohol concentration reached by the mother. The teratology of ethanol has been widely researched over the last four decades, with the link between the neural crest pathology and the fetal alcohol spectrum phenotype becoming clearer. Animal model studies have managed to replicate many of the symptoms seen in humans afflicted with fetal alcohol spectrum disorders, and have allowed us to elucidate the biochemical mechanisms behind the disease. There is no singular pathway responsible for the fetal alcohol spectrum disorders: over half a dozen models of dysfunction have been identified, and ethanol’s ability to react with a series of targets means that more pathways are likely to be discovered. Current theories regarding the effects of ethanol on the neural crest have implicated apoptosis of the cephalic neural crest, mediated by G-protein coupled receptors, activation of a phospholipase C pathway, and subsequent release of intracellular calcium; perturbations of the actin cytoskeleton leading to migration dysfunction of neural crest cells in the developing neural tube; lack of functional trophic molecules, specifically Shh, likely due to dysfunction of the cholesterol biosynthetic pathway; lack of retinoic acid production; oxidative stress, production of reactive oxygen species, and iron dysregulation; and genetics, which seems to confer greater susceptibility and resistance to ethanol in certain individuals. Ultimately, a global model for ethanol’s actions on the developing fetus eludes researchers, as do any potential treatments, and more research is required to further elucidate ethanol’s teratogenic mechanism.

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