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1
Koch, Jill Marie. "Periconceptional treatment with growth hormone alters fetal growth and development in sheep". Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5713.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--West Virginia University, 2008.Title from document title page. Document formatted into pages; contains ix, 128 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
2
Carr, Jillian M. "Insulin-like growth factor binding proteins (IGFBPs) in growth and development of the ovine fetus". Adelaide Thesis (Ph.D.) -- University of Adelaide, Department of Biochemistry, 1994. http://hdl.handle.net/2440/21607.
Testo completo
3
Lunshof, Maria Simone. "Circadian rhythms in the normal and growth-retarded fetus and infant". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2000. http://dare.uva.nl/document/81110.
Testo completo
4
Hoelle, Katharina. "The role of System A amino acid transport in fetal growth and development". Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609768.
Testo completo
5
Zablith, Nadine. "The association between amniotic fluid albumin, prealbumin or transferrin and the fetal growth /". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98526.
Testo completoAbstract (sommario):
The study objectives were to measure the concentrations of albumin, prealbumin and transferrin in amniotic fluid (AF), and to establish if these concentrations were associated with infant birth weight (BW). At St Mary's Hospital (Montreal, Quebec), 294 AF samples were collected from mothers undergoing routine amniocentesis (12-19 weeks gestation). Exclusion criteria included subjects having gestational diabetes, multiple births or fetal genetic abnormalities. AF samples were analyzed by capillary electrophoresis (CE) at 190 nm. Analysis of variance and multiple linear regressions were performed. AF prealbumin could not be detected by CE. However, ANCOVA showed that transferrin was different among BW categories. Multiple regressions showed the parameter estimates for transferrin and albumin were negative, but neither was associated with BW in our study population. In contrast, transferrin was negatively associated with BW in our LBW infants. Our study shows that 2nd trimester AF transferrin may emerge as a biomarker for poor in-utero growth.
6
De, Blasio Miles Jonathon. "Placental restriction and endocrine control of postnatal growth". Title page, table of contents and abstract only, 2004. http://web4.library.adelaide.edu.au/theses/09PH/09phd2869.pdf.
Testo completo
7
Sibley, Colin. "The nutrient exchange phenotype of the placenta in fetal growth restriction : characterization, adaptation and regulation". Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-nutrient-exchange-phenotype-of-the-placenta-in-fetalgrowth-restriction-characterization-adaptation-and-regulation(35a27da9-ad7c-4e7e-8e91-8742304a5c9c).html.
Testo completoAbstract (sommario):
An essential function of the placenta is the exchange of nutrients, and wasteproducts of fetal metabolism, between mother and fetus. The placenta thereforeplays a key role in determining fetal growth and size at birth. Fetal growthrestriction (FGR) is a complication affecting around 5% of pregnancies. Thereare several possible causes of FGR but the most common in the Western world isplacental dysfunction. The FGR baby is at much greater risk of stillbirth andneurodevelopmental morbidities than the normally grown baby. Furthermore, thesmaller baby per se has an increased risk of a range of morbidities as an adult.The thrust of the work covered in this thesis was to improve understanding of theabnormalities in placental exchange physiology associated with FGR. The goalwas (and is) to develop new placental diagnostic biomarkers for the disease andnew treatments based on improving placental function.The first tranche of work described showed that there are specific changes intransporter activities in the placenta in FGR. My colleagues and I showed thatSystem A amino acid transporter activity in the microvillous plasma membrane(MVM) of the syncytiotrophoblast (transporting epithelium of the placenta) isreduced, per mg membrane protein, and that this reduction is related to theseverity of the disease. This contrasted with our observation in normal pregnancythat MVM System A activity, per mg protein, is inversely related to size of the babyat birth, and first suggested the concept of placental adaptation to fetal growthdemand. We, and others, went on to show that a number of other transporters inthe syncytiotrophoblast are altered in FGR. However, not all transporters areaffected and at least one is upregulated. This led me to hypothesise that some ofthese changes are causal to FGR and some are responses, or adaptations, toabnormal fetal growth. The direct causes of transporter activity changes are notknown but our work, and that of others, suggests that glucocorticoids play a role.We also showed that transporter activities in the placenta are affected in othercomplications where fetal growth is aberrant. Furthermore, we provided evidencethat denuded areas of the syncytiotrophoblast might be the morphologicalcorrelate of a route of passive transfer of hydrophilic solutes across the placenta.Our studies in a mouse model of FGR suggest that abnormalities in such aparacellular route may be part of the placental dysfunction in the disease.In the final group of publications of this thesis I describe work showing gestationalchanges in placental transporter activities. I suggest that these are primarilyregulated to maintain fetal growth trajectory, but may also provide for specificnutrient demands at particular times in gestation. This explanation was supportedby work with genetically modified mice showing experimentally that placentaltransporter activity is regulated, or adapted, in relation to fetal growth demand. Itappears from several studies described here that there is a matching of fetalgrowth demand and placental nutrient supply. However, other work shows that thematernal nutritional environment does modify this matching.The studies described here have led to three ongoing lines of investigation: (1)applying knowledge of placental phenotypes of FGR to assist in early diagnosis ofwomen at risk; (2) using mouse models of FGR to test drugs for treating thedisease in humans; (3) investigations into the nature of the fetal nutrient demandsignal(s) to the placenta, and whether these signals are altered in FGR.
8
Lassala, Arantzatzu Leticia. "Arginine and fetal growth in ovine models of intrauterine growth restriction". [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3238.
Testo completo
9
Burrage, Deborah. "The impact of reduced nutrition on growth and cardiovascular control in the fetus". Thesis, University of Southampton, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430705.
Testo completo
10
Carr, D. "Evaluation of prenatal adenoviral vascular endothelial growth factor gene therapy in the growth-restricted sheep fetus and neonate". Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1401185/.
Testo completoAbstract (sommario):
Background - Fetal growth restriction (FGR) is associated with reduced uterine blood flow (UBF). In normal sheep pregnancies, adenovirus (Ad) mediated over-expression of vascular endothelial growth factor (VEGF) in the uterine arteries (UtA) increases UBF. It was hypothesised that enhancing UBF would improve fetal substrate delivery in an ovine paradigm of FGR characterised by reduced UBF from mid-gestation. Methods - Singleton pregnancies were established using embryo transfer in adolescent ewes subsequently overnourished to generate FGR (n=81). Ewes were randomised mid-gestation to receive bilateral UtA injections of 5x1011 particles Ad.VEGF-A165 or inactive treatment (saline or 5x1011 particles Ad.LacZ, a control vector). Fetal growth/wellbeing were evaluated using serial ultrasound. Late-gestation study: UBF was monitored using indwelling flowprobes until necropsy at 0.9 gestation. Vasorelaxation, neovascularisation in perivascular adventitia and placental mRNA expression of angiogenic factors/receptors were examined. A group of control-fed ewes with normally-developing fetuses was included (n=12). Postnatal study: Pregnancies continued until spontaneous delivery near to term. Lambs were weighed and measured weekly and underwent metabolic challenge at 7 weeks, dual-energy X-ray absorptiometry at 11 weeks, and necropsy at 12 weeks postnatal age. DNA methylation of somatotropic genes was examined in hepatic tissues. Results - Ultrasonographic fetal growth velocity was greater in Ad.VEGF-A165-treated versus control-treated FGR fetuses at 3-4 weeks post-injection. In late gestation fewer fetuses were markedly growth-restricted following Ad.VEGF-A165 therapy. There was evidence of mitigated brain sparing. No effect was seen on UBF/neovascularisation although Ad.VEGF-A165-transduced vessels showed enhanced vasorelaxation. Flt1/KDR expression was increased in the maternal placental compartment. At birth Ad.VEGF-A165-treated lambs tended to be heavier with increased placental efficiency. Postnatal growth, lean tissue accretion and insulin secretion were also increased, however no epigenetic changes were observed. Conclusions - Ad.VEGF-A165 safely increases fetal growth in this ovine model of FGR. This work has supported a successful application to translate this therapy into the clinic.
11
Yunusova, Roza. "Effects of Maternal Nutrition, Intrauterine Growth Restriction (IUGR), and Estrogen (E2) Supplementation on Placental and Fetal Intestinal Growth and Development in Sheep". Thesis, North Dakota State University, 2012. https://hdl.handle.net/10365/26539.
Testo completoAbstract (sommario):
The placenta and fetal intestines are two key nutrient transport organs that sustain and nurture growing fetus. Insufficient placental development and consequently inadequate fetal nutrient supply can lead to IUGR resulting in low birth weight offspring. Our experimental objectives were to investigate the effects of elevated maternal nutrition, IUGR, and E2 supplementation during mid-gestation (in an attempt to rescue IUGR offspring) on placental and fetal intestinal cell proliferation, angiogenic gene expression, and vascularity. Limited responsiveness in placental development and vascularization to E2 supplementation was observed, likely due to inappropriate timing or dose of E2. However, maternal E2 supplementation increased fetal small intestinal length and GUCY1b3 mRNA expression, suggesting that E2 supplementation has positive effects on IUGR fetal intestinal growth. In conclusion, understanding molecular mechanisms associated with IUGR and possible effects of E2 supplementation in rescuing IUGR may lead to enhanced human health and livestock production efficiency.
12
Турова, Людмила Олександрівна, Людмила Александровна Турова, Liudmyla Oleksandrivna Turova e A. M. Waal. "Cobalt exchange in the system "Mother-placenta-fetus" in case of intrauterine growth retardation". Thesis, Видавництво СумДУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/27538.
Testo completo
13
O'Regan, Shaun. "A critical evaluation of the accuracy of foetal age estimation by sonographic biometry at Ipswich Hospital". Thesis, Queensland University of Technology, 1991. https://eprints.qut.edu.au/35980/1/35980_O%27Regan_1991.pdf.
Testo completoAbstract (sommario):
Diagnostic Ultrasound plays an important role in the
management of the obstetric patient, particularly in
relation to the estimation of foetal age in cases of
clinical uncertainty. The sonographic determination of
foetal maturity is based on the correlation of ultrasonic
measurements of selected anatomical parameters
with age estimates in biometric nomograms. The
prediction of foetal age at Ipswich General Hospital has
been based on biometric models developed by Hadlock. 45
The accuracy of these models in predicting foetal age in
patients at Ipswich Hospital is evaluated. Significant
errors in predicted foetal age are revealed and factors
contributing to these errors are highlighted.
Biometric models which more accurately predict foetal
age in the obstetric patient population at Ipswich
Hospital are developed by regression analysis of data
derived from a study sample of 346 patients with known
gestational age and normal foetal growth.
14
Illa, Armengol Míriam. "Brain effects of fetal growth restriction and their prevention in an animal model". Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/565667.
Testo completoAbstract (sommario):
BACKGROUND: Chronic hypoxia due to placental insufficiency and prenatal undernutrition are probably the two major causes worldwide of an adverse intrauterine environment having an impact on neurodevelopment. Clinically, both situations manifest as an intrauterine growth restriction (IUGR), a situation defined as a significant reduction in fetal growth resulting in a birth weight below the 10th percentile. This situation is a well-recognized cause of neurobehavioral and cognitive impairments extending beyond childhood and early adulthood period. Although all these evidence, the structural ground of these functional impairments and the pathophysiological mechanisms are not fully characterized. An improvement in these two aspects would allow us to propose different therapeutic strategies aiming to ameliorate and even revert the long-lasting consequences of the IUGR.
HYPOTHESIS: We hypothesized that IUGR produces subtle structural brain changes that underlie the long-term neurobehavioral and cognitive impairments. The severity of the neurodevelopmental consequences might be related to the severity of the prenatal insult (reduction in nutrients with or without a reduction in oxygen). High-resolution brain imaging along with specific histological techniques focused on neuronal connectivity could evidence these structural brain changes. Additionally, we hypothesized that an early postnatal stimulation might ameliorate the structural and functional impairments that persist at the long-term period after IUGR.
METHODS: Two animal models of IUGR were used in this thesis: i. A cohort of pregnant rabbits was randomized to reproduce an undernutrition model based on maternal food reduction intake, ii. Another cohort of pregnant rabbits was randomized to the placental insufficiency model based on the surgical ligation of 40-50% of the uteroplacental vessels that irrigate each gestational sac. After the delivery in both models, IUGR and controls animals were followed up to the 70th postnatal days. At the 30th postnatal days, a subgroup of IUGR animals was randomized to an environmental enrichment strategy. In all the groups at the neonatal period, general motor skills, reflexes, and olfactory sensitivity were evaluated. Similarly, at the 70th postnatal days, anxiety, memory, and learning were evaluated. Afterward, animals were sacrificed and brains were fixed and diffusion MRI was then performed. In a subset of animals, changes at the microstructural level and differences in the number of fibers in two specific brain circuits (anxiety and memory circuits) were performed by using a Voxel-Based approach
(VBA) and Tractography analysis, respectively. Moreover, brain networks were obtained and evaluated by means of a Connectomics. Finally, a subgroup of animals was also histologically evaluated by means of dendritic spine and perineural nets evaluation in the Hippocampus.
RESULTS: IUGR animals showed poorer functional performance in both moments, especially in the model of placental insufficiency. At the long-term period, IUGR animals presented an altered brain network architecture, being again these differences more pronounced in the placental insufficiency model. Moreover, VBA analysis and Tractography analysis evidenced microstructural brain changes mostly affecting gray matter and a decreased in the number of fibers involved in the anxiety and memory circuits in the IUGR animals in comparison to controls. At the cellular level, IUGR animals presented abnormal neuronal connectivity with changes in the dendritic spine density and in the perineural nets. In contrast, stimulated IUGR animals presented a functional and structural improvement in comparison to non-stimulated IUGR animals over the long-term period.
CONCLUSIONS: This thesis adds to the previous evidence new insights regarding the pathophysiological mechanisms underlying IUGR and gives strong evidence linking IUGR with altered brain connectivity as the basis for the neurological sequelae associated with IUGR. Additionally, it gives preliminary evidence suggesting that a strategy based on physical, sensory, cognitive as well as social stimulation applied during early postnatal life, where brain plasticity is higher, might ameliorate the neurodevelopmental consequences of IUGR.
15
Elian, Kelly Marie. "The relation between amniotic fluid constituents and human fetal growth". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0019/MQ55051.pdf.
Testo completo
16
Lavranos, Tina Christine. "Maternal-embryo interactions at the time of implantation in early pregnancy /". Adelaide : Thesis (Ph.D.) -- University of Adelaide, Department of Obstetrics and Gynaecology, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phl414.pdf.
Testo completo
17
Lavranos, Tina C. "Maternal-embryo interactions at the time of implantation in early pregnancy / by Tina Christine Lavranos". Adelaide Thesis (Ph.D.) -- University of Adelaide, Department of Obstetrics and Gynaecology, 1993. http://hdl.handle.net/2440/21664.
Testo completoAbstract (sommario):
1 v.Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Thesis (Ph.D.)--University of Adelaide, Dept. of Obstetrics and Gynaecology, 1993
18
Lavranos, Tina C. "Maternal-embryo interactions at the time of implantation in early pregnancy / by Tina Christine Lavranos". Thesis, Adelaide Thesis (Ph.D.) -- University of Adelaide, Department of Obstetrics and Gynaecology, 1993. http://hdl.handle.net/2440/21664.
Testo completo
19
Sterle, Jodi A. "Effect of recombinant porcine somatotropin (rpST) on placental and fetal growth in gilts /". free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9901288.
Testo completo
20
Louey, Samantha 1977. "The effects of intrauterine growth restriction on postnatal growth, arterial pressure and the vasculature". Monash University, Dept. of Physiology, 2003. http://arrow.monash.edu.au/hdl/1959.1/7939.
Testo completo
21
Howe, David Thomson. "The influence of maternal haemoglobin and ferritin on the growth of the placenta and fetus". Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295714.
Testo completo
22
Gurekian, Christine N. "Amniotic fluid amino acids as biological indicators of fetal growth in human and rat models". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98718.
Testo completoAbstract (sommario):
Amniotic fluid (AF) is a protective pool and a resource of amino acids for the growing fetus. In study 1, we investigated if any of these AF amino acids at mid gestation were associated with fetal development in humans. Nineteen amino acids differed across birth weight percentiles. Arginine, 3-methyl histidine and tryptophan were positive predictors of birth weight, while ornithine was a negative predictor. In study 2, we used a diet induced model of IUGR to see if specific AF amino acids were predictive of fetal weight near term. Methionine and phenylalanine were modified by diet, and 12 amino acids were independently modified by gestational age, respectively. Cysteine, lysine, methionine and tyrosine were predictors of fetal weight. Thus, the AF amino acid pool is associated in animals and humans with fetal growth.
23
Lam, Shih-en, e 林詩恩. "A pilot study on potential involvement of epigenetic regulations secondary to perturbed intrauterine environment". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41509018.
Testo completo
24
Renshall, Lewis. "Antenatal sildenafil citrate treatment in a mouse model of fetal growth restriction : effects on fetus and offspring". Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/antenatal-sildenafil-citrate-treatment-in-a-mouse-model-of-fetal-growth-restriction-effects-on-fetus-and-offspring(c7512bee-9109-404d-a977-7eb9f3c50172).html.
Testo completoAbstract (sommario):
Fetal growth restriction (FGR), when a fetus fails to reach its genetic growth potential, affects up to 10 % of pregnancies and is a major risk factor for both neonatal and adulthood morbidity and mortality. There are currently no treatments for FGR except for delivery of the fetus; resulting in premature delivery which, in itself, is linked to poor outcome. Therefore, the focus of current research is to examine whether therapies successfully used to treat diseases with similar aetiologies to FGR can also be used to treat FGR. Sildenafil citrate (SC), a selective phosphodiesterase-5 inhibitor, is one such candidate. With the recent announcement of the STRIDER international clinical trial for the treatment of severe FGR with SC, it is imperative to determine the efficacy and safety of SC treatment on both fetus in utero and long-term adult health. Mouse models that mimic characteristics of human FGR represent an attractive model to perform pre-clinical studies. Recent studies in mice have demonstrated that SC increased fetal and placental weight and normalised umbilical artery blood flow velocity in FGR but no studies have assessed effects of antenatal SC on offspring health. The aims of this study were to assess the effect of antenatal SC treatment on a) fetal weight b) fetal vascular reactivity b) pup viability and d) long-term effects on postnatal development/physiology in a mouse model of FGR.All experiments were performed in the placental-specific insulin-like growth factor 2 knockout mouse (Igf2 P0+/- mice) which have mixed litters of wild-type (WT) and growth restricted (P0) mice. It has been reported that SC administered in the drinking water was able to increase P0 fetal weight and thus this mouse model was chosen to assess the effects of SC on the fetus and offspring. SC was administered to pregnant dams in two regimens; orally (120 – 160 mg.kg-1) and subcutaneously (10 mg.kg-1) between E12.5 and E18.5. WT and P0 fetal abdominal aortas were isolated at E18.5 and ex vivo vascular function was assessed using wire myography. Fetal abdominal aortas demonstrated reliable and reproducible vasocontraction and vasorelaxation; there were some sex- and genotype-specific differences. SC demonstrated dose-dependent effects on fetal aortic function. Offspring from dams treated with a subcutaneous injection of SC or saline were assessed for postnatal growth (week 5 – week 12), systolic blood pressure (week 8 and week 13), glucose tolerance (week 12) and mesenteric / aortic vascular function (week 14 – week 16). These experiments demonstrated that;• A supratherapeutic concentration of antenatal SC (120 – 160 mg.kg-1) did not increase fetal weight but significantly blunted relaxation responses of fetal abdominal aortas at E18.5. • A subcutaneous injection of antenatal SC (10 mg.kg-1) did not increase fetal weight or alter fetal abdominal aortic function in mice but led to increased systolic blood pressure in both WT and P0 offspring. Additionally, glucose sensitivity was significantly reduced in female offspring from SC treated dams. In conclusion, the studies outlined in this thesis have demonstrated that antenatal SC treatment can cause alterations in fetal blood vessel function and also lead to changes in metabolic and cardiovascular function in mouse offspring. Using ex vivo wire myography, mouse fetal abdominal aortas were able to be assessed at E18.5. This methodological advance will be beneficial as it can be applied to assessing putative treatments in mice that show characteristics of human FGR. In addition, this technique will allow for investigation of the underlying mechanisms of in utero programming of adulthood cardiovascular diseases such as hypertension. Future work must focus on the mechanisms leading to increased systolic blood pressure in offspring from SC treated dams and whether such effects are noted in other animal models of FGR using a variety of SC dosing regimens. These studies will provide information with which to increase efficacy, and ensure the safety, of SC treatment in pregnancy complications.
25
Rubino, Maria. "Second trimester amniotic fluid insulin and glucose as predictors of macrosomia". Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=111582.
Testo completoAbstract (sommario):
Using second trimester amniotic fluid (AF), the objectives of this study were two-fold: 1) to investigate the relationship between AF glucose and insulin levels as a predictor of macrosomia and 2) to create a risk profile for macrosomia (LGA> 90th percentile) using a combination of AF glucose and insulin concentrations. Amniotic fluid samples were obtained from non-diabetic women (n = 542) undergoing age-related amniocentesis (12th to 22nd week). AF glucose was quantified using a standard hexokinase assay and AF insulin was quantified using the Beckman Access ultrasensitive assay system. Although LGA infants were found to have significantly higher concentrations of insulin and glucose in their 2nd trimester AF, logistic regressions showed that neither alone predicted the outcome of macrosomia. However, a Bayesian two-dimensional contour map plotted the risk for LGA using both AF glucose and insulin. The two-dimensional contour map illustrated the value in considering AF glucose and insulin together to predict LGA in newborns.
26
Santos, Victor José Correia. "Ultrassonografia modo b e dopplerfluxometria materno fetal na avaliação gestacional de ovelhas /". Jaboticabal, 2017. http://hdl.handle.net/11449/152361.
Testo completoAbstract (sommario):
Orientador: Wilter Ricardo Russiano VicenteCoorientador: Maria Emilia Franco Oliveira
Coorientador: Marcus Antônio Rossi Feliciano
Banca: Luciana Cristina Padilha Nakaghi
Banca: Felipe Farias Pereira da Câmara Barros
Banca: Erika da Silva Carvalho Morani
Banca: Eliandra Antonia Pires Buttler
Resumo: O entendimento acerca da fisiologia do processo gestacional e desenvolvimento embrionário/fetal oferece conhecimento para que se tome decisões acertadas em relação ao manejo da fêmea gestante, além destes animais serem utilizados como modelo experimental para a medicina humana, o que reforça a importância do estudo da gestação em ovinos. Nesse contexto, a ultrassonografia se apresenta como melhor opção para avaliar o desenvolvimento da gestação. É uma tecnologia segura que permite que se façam avaliações repetidas durante todo o processo gestacional. Objetivou-se estudar o desenvolvimento fisiológico embrionário/fetal durante a gestação de ovelhas por meio da ultrassonografia a fim de se obter parâmetros de normalidade que possam ser utilizados como referência para o diagnóstico de possíveis alterações do desenvolvimento embrionário/fetal e desenvolver fórmulas para predição de idade gestacional. Foram utilizadas 30 ovelhas Santa Inês pesando 45,4±4,3 kg, entre 2 e 5 anos e realizados exames ultrassonográficos semanais desde a 3ª, até a 21ª semana gestacional. Para a análise estatística, realizou-se teste de "Shapiro" para normalidade, com medidas reais ou transformadas correlacionadas com as semanas gestacionais pelo teste de "Spearman". Quando significativo, foram testados os ajustes dos parâmetros e semanas gestacionais à modelos de regressão. Foi utilizado nível de significância de 5% e os resultados apresentados como média±DP (desvio padrão). Foram avaliados os diâmetros... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The understanding about the physiology of the gestational process and embryonic/fetal development offers tools to make wise decisions regarding the management of the pregnant female, besides, these animals are used as experimental models, which reinforces the importance of the study of gestation in sheep. In this context, ultrasonography is the best option for the evaluation of gestation. It is safe and allows repeated evaluations to be made throughout the gestational process. The objective of this study was to assess the embryonic/fetal physiological development during pregnancy of sheep by means of ultrasonography in order to obtain normality parameters that can be used as a reference for the diagnosis of embryonic/fetal development alterations and to develop formulas for estimate gestational age. Thirty Santa Ines sheep weighing 45.4±4.3kg, between 2 and 5 years old were used. Ultrasound examinations were performed weekly from the 3rd to the 21st gestational week. For the statistical analysis Shapiro test was performed for normality with real or transformed measurements correlated with the gestational weeks by the Spearman test. When significant, parameter adjustments and gestational weeks were tested for regression models. A significance level of 5% was used and the results presented as mean ± SD (standard deviation). The gestational vesicle (GV), abdominal (AD), thoracic (TD), biparietal (BPD), ocular orbit (OO) and placentonium (PL) diameters were evaluated, as well as ... (Complete abstract click electronic access below)
Doutor
27
Chidzanja, Stivelia. "Restricted implantation and undernutrition alter development and growth of the ovine placenta". Title page, abstract and contents only, 1994. http://hdl.handle.net/2440/18519.
Testo completoAbstract (sommario):
Bibliography: 161-199.[xxvi], 199, [151] leaves, [7] leaves of plates : ill. (some col.) ; 30 cm.
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Characterises the normal otogeny of the cellular composition and structure of placentomes in sheep, their relationship to the macroscopic parameters of placentome size and morphology, and the effect of experimental and natural restriction of implantation on the growth and development of placentomes between mid and late gestation.
Thesis (Ph.D.)--University of Adelaide, Dept. of Obstetrics and Gynaecology, 1995
28
Boland, Rochelle Elizabeth 1974. "Factors affecting structural development of the lung in fetal sheep". Monash University, Dept. of Physiology, 2002. http://arrow.monash.edu.au/hdl/1959.1/8135.
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29
Xu, Wei. "The impact of rhizoma chuanxiong in fetal bone development". HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/253.
Testo completoAbstract (sommario):
Background and purpose: Rhizoma Chuanxiong (CX), the dry rhizome of Ligusticum chuanxiong Hort., is a commonly used Chinese herbal medicine to treat gynecological diseases. So far, more than 60 chemical components have been identified from CX such as volatile oils (ligustilide, etc.), phenolic acids (ferulic acid, etc.) and alkaloids (chuanxiongzine, etc.). These components in CX are the basis of its wide pharmacodynamic actions including estrogen-like, progesterone-like and anti-coagulant/anti- platelet effects. In our recent survey based on previous published clinical trials, CX was ranked as one of the top 20 herbs commonly used for anti-miscarriages amongst Chinese pregnant women. However, CX should be used with caution during pregnancy as its property of 2invigorating blood circulation and removing blood stagnation3. Despite its wide applications, the safe dosage of CX in pregnant women remains unclear with no records found in the current Chinese Pharmacopoeia or other guidelines. Thus, verification regarding the impacts of CX preparations and its components in embryonic development is urgently required. In view of the limited experimental evidence that is currently available to assess the safety of CX, this project aims to (1) identify the general impacts of CX aqueous extract in maternal function and fetal development with an in vivo mouse model; and to (2) investigate the adverse impacts and underlying mechanisms of CX aqueous extract in fetal bone development with a biomarker assay and metabolomics analysis.;Concusion: CX aqueous extract at a low dosage of 2 g/kg/day (equals to the daily dosage of human adults) did not cause adverse effect in pregnant mice, and it suggested that this dosage of CX preparations should be safe for pregnant women. Our data demonstrated that high dosage and long-term use of CX aqueous extract might result in embryonic toxicities including fetal bone malformations for the first time. As the CX aqueous extract in this study was not contaminated by pesticide residues and heavy metals, the adverse impacts of CX aqueous extract should be considered as a result of its intrinsic components in the herb. Furthermore, CX aqueous extract might significantly down-regulate biomarkers related to bone formation and metabolism during osteogenesis. It is therefore valuable to establish a practical approach to systematically assess the safety of CX and other herbal medicines.;Method: Referred to the guidelines of WHO, the Chinese Pharmacopoeia and the Hong Kong Chinese Materia Medica Standards, CX aqueous extract was prepared, and its reference marker (ligustilide and ferulic acid) were quantitatively authenticated by HPLC analysis. LC/MS fingerprint analysis was performed for the quality control purposes. In addition, pesticide residues and heavy metals found in CX aqueous extract were examined using GC-MS and ICP-MS analysis. In the Segment II study as per FDA and OECD guidelines, pregnant mice were randomly assigned into 6 groups (n=18 per group): i.e. mice were orally administrated with distilled water as the negative controls (Group 1); or CX aqueous extract of 2, 16, 24 and 32 g/kg/day respectively from the gestation day (GD)6 to 16(Group 2, 3, 4 and 5); or vitamin A (200,000 IU) on GD7, 9 and 11 as the positive controls (Group 6). All mice were sacrificed to assess maternal and fetal parameters on the GD18. In the mechanistic study, the expressions of biomarkers related to fetal bone development including PICP, ICTP, B-ALP, BGP, Gdf-5, BMPs, BMP-6, BMP-8, BMP-11, IL-4, IL-4r, IL-10 and IL-10r in fetal tissue samples of the Group 1 and 5 (32 g/kg/day, n=18) were measured using ELISA analyses on GD16. Meanwhile, the metabolites of two-group samples were also analyzed by the UHD Accurate-Mass Q- TOF LC/MS, and profiling data was further analyzed by specific software. During statistical analysis, measurement data from G1, 2, 3 4 and 5 groups were analyzed using one-way ANOVA(SPSS software, version 16.0). LSD test in Post hoc method was applied to compare differences between every two groups. Pearsons x 2 - test was used to analyze category data from G1, 2, 3, 4 and 5 groups, and Fishers exact test was applied to compare differences between different groups. The student t-test was also used to compare differences between G1 and G6 groups in animal studies as well as G1 and G5 groups using ELISA or metabolomics results. An intragroup difference with a p-value less than 0.05 was considered as statistical significant.;Resutt:(1) There was no statistical significant difference in maternal and fetal parameters found between the Group 1 and 2 (p> 0.05). However, the maternal body weight (BW), gravid uterine weight, corrected BW change, live fetus/litter, mean fetal BW in the Group 4 and 5 were significantly lower than those in the Group 1(p
30
Lam, Shih-en. "A pilot study on potential involvement of epigenetic regulations secondary to perturbed intrauterine environment". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41509018.
Testo completo
31
Comas, Rovira Montserrat. "Cardiac dysfunction by tissue doppler in earty-and late-onset fetal growth restriction". Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/51517.
Testo completoAbstract (sommario):
SUMMARY
1) Background
Fetal growth restriction (FGR) is present in 5-10% of the pregnancies and is associated to high perinatal and long-term cardiovascular morbidity. Subclinical cardiac dysfunction has previously been described in severe and early FGR cases, but not in milder forms of late-FGR. The main aim of this thesis was to assess cardiac function by new echocardiographic techniques on myocardial imaging as Tissue Doppler Imaging (TDI), in early- and late-onset FGR cases.
2) Methods
First, tissue Doppler was applied in a cohort of normally growth fetuses by TDI in order to describe its reproducibility and construct reference ranges for fetal annular peak velocities and myocardial performance index at 24-41 weeks of gestation.
Secondly, cardiac function including conventional echocardiographic parameters and TDI was evaluated in a cohort of early-onset growth restricted fetuses with abnormal umbilical artery (UA) Doppler and, finally, in a cohort of late-onset small for gestational age (SGA) fetuses with normal UA Doppler.
3) Results
Fetal TDI measurements demonstrated a good reproducibility. GA and estimated fetal weight (EFW) adjusted reference ranges for tissue Doppler indices at 24-41 weeks of gestation were provided. TDI demonstrated the presence of both systolic and diastolic cardiac dysfunction in early-onset FGR fetuses. Late-onset FGR fetuses with normal UA were also associated with cardiac dysfunction detected by TDI.
4) Conclusions
Early- and late-onset growth restricted fetuses are associated with cardiac dysfunction. Subclinical cardiac dysfunction could be present from early stages of fetal deterioration and could be detected using TDI.
32
Kakar, Muhammad Azam. "Effect of peri-conceptional feed intake on early embryo development and fetal growth in the Merino ewe /". Title page, table of contents and abstract only, 2003. http://web4.library.adelaide.edu.au/theses/09ANP/09anpk138.pdf.
Testo completo
33
Moore, Vivienne M. "Fetal growth and cardiovascular risk factors in an Australian cohort /". Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phm824.pdf.
Testo completo
34
El-Halabi, Dima. "Oxidative and nitrative stress biomarkers in amniotic fluid and their association with fetal growth and pregnancy outcomes". Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101119.
Testo completoAbstract (sommario):
The study objectives were to: (1) assess fetal exposure to oxidative stress by measuring amniotic fluid concentrations of nitric oxide (NO), thiobarbituric acid--reactive substances (TBARS), and ferric reducing antioxidant power (FRAP) and (2) establish whether these concentrations were associated with infant birth weight, gestational age, or oxidative stress-related conditions arising during pregnancy. Frozen amniotic fluid samples were obtained from 654 mothers undergoing amniocentesis for genetic testing during second trimester in Montreal, QC, Canada. Maternal and neonatal characteristics were collected from medical charts and questionnaires and exclusion criteria were applied. ANOVAs and multivariate regression analyses showed that NO, which differed among pre-term, term, and post-term groups, was a positive predictor of gestational age. TBARS were highly correlated with sample storage and were not associated with pregnancy outcome parameters. FRAP positively predicted gender-corrected birth-weight-for-gestational-age. Our study shows that markers of oxidative and nitrative stress in-utero are associated with pregnancy outcomes.
35
Lok, Fong. "Role of IGF-I in ovine fetal and placental growth and development /". Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09PH/09phl836.pdf.
Testo completo
36
Vaughn, Mathew Alan. "Characterization of intra-litter variation on myogenic development and myogenic progenitor cell response to growth promoting stimuli". Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34595.
Testo completoAbstract (sommario):
Doctor of PhilosophyDepartment of Animal Sciences and Industry
John M. Gonzalez
This series of studies focuses on the impact of intra-litter variation on fetal myogenesis, and the ability of porcine progenitor cells to respond to growth promoting stimuli. In study 1, the smallest (SM), median (ME), and largest (LG) male fetuses from each litter were selected for muscle morphometric analysis from gilts at d-60 ± 2 and 95 ± 2 of gestation. On d-60 and 95 of gestation LG fetuses had greater whole muscle cross-sectional area (CSA) than ME and SM fetuses, and ME fetuses had greater whole muscle CSA than SM fetuses. Indicating that SM and ME fetuses are on a delayed trajectory for myogenesis compared to LG fetuses. At d-60 the advanced trajectory of LG compared to ME fetuses was due to increased development of secondary muscle fibers; whereas, the advanced myogenic development of LG and ME fetuses compared to SM fetuses was due to the presence of fewer primary and secondary muscle fibers. At d-95 of gestation the advanced myogenic development of LG and ME was due to increased hypertrophy of secondary muscle fibers. For study 2, porcine fetal myoblasts (PFM) were isolated from SM, ME, and LG fetuses from d-60 ± 2 of gestation fetuses and for study 3, porcine satellite cells (PSC) were isolated from the piglet nearest the average body weight of the litter. Both myogenic cell types were utilized to evaluate effects of porcine plasma on proliferation, differentiation, and indications of protein synthesis. For the proliferation assay, cells were exposed to one of three treatments: high serum which consisted high-glucose Dulbecco's Modified Eagle Medium supplemented with 10% (vol/vol) fetal bovine serum, 2% (vol/vol) porcine serum, 100 U penicillan/mL, 100 µg of strepmycin/mL, and 20 µg of gentamicin/mL (HS), low serum which consisted of HS without 10% FBS (LS), and LS supplemented with 10% (wt/vol) porcine plasma (PP). Treatments for the differentiation and protein synthesis assays consisted of either HS or LS media that either contained porcine plasma at 10% (wt/vol; PPP) or 0% (wt/vol; PPN). The HS-PFM had a greater proliferation rate compared to the LS and PP-PFM, and PP-PFM had a greater proliferation rate compared to LS-PFM. The LG fetuses’ PFM had a reduced proliferation rate compared to SM and ME fetuses’ PFM, which were similar. The PPP-PFM had a decreased myotube diameter compared to PPN-PFM. Small fetuses’ PFM had a greater myotube diameter compared to ME and LG fetuses’ PFM, and ME fetuses’ PFM had a greater myotube diameter compared to LG fetuses’ PFM. The proliferation rate of PP-PSC was decreased compared to the HS- and LS-PSC, and HS-PSC had a greater proliferation rate compared to LS-PSC. The PPP-PSC had greater differentiation capacity and myotube diameter than PPN-PSC. In conjunction these results indicate divergent myogenic development among different fetal sizes within a litter and suggest that porcine plasma supplementation stimulates myogenic progenitor cell activity in an age specific manner.
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Li, Yuhong, e n/a. "Effect of alcohol exposure in early gestation on brain development". University of Otago. Department of Anatomy & Structural Biology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20070502.100319.
Testo completoAbstract (sommario):
Fetal alcohol spectrum disorders (FASD), caused by maternal alcohol consumption during pregnancy, has been extensively studied in the human. Animal studies show that alcohol exposure during very early development may result in severe brain damage, often incompatible with a postnatal life. However, for surviving offspring it is unknown whether they suffer long term brain damage. The final assembly of the mature brain results from a controlled balance between proliferation of glial and neuronal precursors and programmed cell death. The overall aim of the current study was to use a physiologically relevant mouse model to assess the acute and long-term effects of binge alcohol exposure on the early embryo, to simulate human pregnancy at the third week of gestation when pregnancy may be undetected.
A number of paradigms were used to assess the acute dose-response effect, the blood alcohol concentration (BAC) profile and the extent of cell death following alcohol exposure on gestational day (G) 7.5. The exposure paradigms were single binge IG6.5, IG4.5, IP4.5, or an extended binge IG4.5+, IG3.0+. Two control groups were Con6.5 and Con4.5+. Acute cell death was determined using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), activated caspase-3 staining, and transmission electron microscopy. Cell proliferation was investigated using S-phase immuno-labeling, bromodeoxyuridine (BrdU) birthdating and immuno-detection (BrdU/anti-BrdU). The long-term effects were investigated at G18.5 and postnatal day (PN) 60. Unbiased stereological methods were used to assess the effect of ethanol exposure at G7.5 on neocortical volume, cell number and density of neurons, glial cells, and capillary cells at PN60.
The first principal finding of the present study was that binge ethanol exposure during gastrulation resulted in acute apoptotic cell death in the ectoderm of the mouse embryo. Cell death was dependent on both peak BAC and the duration of elevated BAC. Significant increased cell death (TUNEL labeling) was observed in groups IG6.5 (9.43 � 2.08%) and IG4.5+ (8.97 � 2.12%) compared with control groups Con6.5 (2.14 � 0.09%) and Con4.5+ (2.81 � 0.36%). There was no significant increased cell death in ethanol exposed groups IG4.5 (3.43 � 0.45%), IP4.5 (3.68 � 0.67%), or IG3.0+ (1.72 � 0.24%). TEM analysis revealed that cell death exhibited characteristics of the apoptotic pathway.
The second principal finding of the present study was that binge ethanol exposure during gastrulation resulted in acute arrested proliferation in the ectoderm of the mouse embryo. The S-phase proliferation was significantly decreased within the whole ectoderm in the ethanol exposed group IG6.5 (45.58 � 2.34%) compared with control group Con6.5 (62.08 � 3.11%).
The third principal finding of the present study was that binge ethanol exposure during gastrulation induced the long term effect of laminate disorganization in the neocortex. The incidence of abnormal lamination was 87.5% in IG6.5 compared with 16.7% in IG3.0+ and 14.3% in Con6.5. Although ethanol exposure increased embryonic reabsorption, decreased litter size, and increased abnormal offspring, neocortical volume, and the total number of neurons, glial cells, and capillary cells was not affected. The total number (10⁶) of neurons, glial cells, and endothelial cells respectively was 12.221 � 0.436, 4.865 � 0.167, and 2.874 � 0.234 in IG6.5; 11.987 � 0.416, 4.942 � 0.133, and 2.922 � 0.130 in IG3.0+; and 11.806 � 0.368, 5.166 � 0.267, and 3.284 � 0.217 in controls, at PN60.
These results provide important information pertinent to fetal outcome for those women who drink heavily in early pregnancy. The results also demonstrate the importance of the pattern of ethanol exposure and blood alcohol concentration in determining the magnitude of ethanol�s teratogenic impact. Ethanol exposure on G7.5 that resulted in a high transient BAC, induced disorganized neocortical lamination, indicative of a permanent structural change. This disruption may result in altered neocortical function and requires further investigation.
38
Enros, Erin. "Amniotic fluid fatty acids and cholesterol and their association with pregnancy outcomes". Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99341.
Testo completoAbstract (sommario):
The objectives were (1) to establish a profile of total fatty acids and cholesterol in amniotic fluid (AF) as well as (2) to determine possible associations between AT fatty acids (micromolar and relative proportion) with gestational age and birth weight. A total of 208 AF samples collected between 12 and 22 weeks of gestation during routine amniocentesis were analyzed using tandem column gas chromatography (GC). Smoking increased AF polyunsaturated fatty acid (PUFAs) levels while developmental stage and storage time decreased AF fatty acid quantities. AF trans fatty acids (TFAs) were negatively associated with both birth outcomes, whereas specific fatty acids including stearic acid (C18:0) and gondoic acid (C20:1n-9) were identified as negative predictors for gestational age and birth weight respectively. This study demonstrated novel relationships between fatty acids and fetal growth and gestational age in early midgestation AF, suggesting a possible role of AF fatty acids in predicting birth outcomes.
39
Crang-Svalenius, Elizabeth. "The use of routine ultrasound in pregnancy with special reference to normal and abnormal foetal growth, information and informed choice and the womens' experiences of the prenatal diagnostic aspects /". Lund : Lund University, Dept. of Obstetrics and Gynaecology, University Hospital, 1997. http://catalog.hathitrust.org/api/volumes/oclc/39072830.html.
Testo completo
40
Di, Giovanni Jessica Louise. "Early second trimester amniotic fluid erythropoietin and pregnancy outcomes". Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112615.
Testo completoAbstract (sommario):
The study objective was to determine whether early 2 nd trimester amniotic fluid (AF) erythropoietin (EPO) was associated with and predictive of (a) development of maternal gestational diabetes (GDM) and (b) the infant outcome parameters of (i) gestational age at birth (GAAB) assessed exclusively among spontaneous vaginal deliveries or (ii) birth weight (measured in grams and percentiles). Enzyme-linked-immunosorbent assay was used to determine the EPO concentration of 170 biobanked AF samples. Student's t-test revealed no difference between GDM and non-GDM subjects. AF EPO was not predictive of GAAB despite being significantly greater among preterm infants compared to post-term infants. In contrast, AF EPO was significantly higher among the smallest infants using both birth weight classification schemes. However, following inclusion of known covariates AF EPO was predictive of gram birth weight only. Early 2nd trimester AF EPO may emerge as a useful biomarker of fetal nutritional status and/or growth.
41
Johnsen, Suzanne Louise 1960. "Early embryos of dams of heat stress". Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277034.
Testo completoAbstract (sommario):
Increased environmental heat causes early embryonic death before implantation. This study was designed to examine tissues of dams exposed to environmental temperatures of 36°C and to examine 72 hour old embryos from these dams. Results showed adult mice exposed to heat stress had significant changes in liver morphology with hepatocyte swelling and vacuolization of the cytoplasm, organelles in the hepatocytes were displaced next to the cell membrane. After 48 hours of recovery from heat stress, liver morphology appeared normal. Embryos from heat stressed dams had delayed development indicated by increased 2alpha helical cellular inclusions. Embryos responded differently to different fixation techniques indicated permeability changes in either the zona pellucida or cellular membranes. Litter size or pup survivability from heat stressed dams allowed to recover indicated changes seen at this point were reversible
42
Hebert, Jessica Faith. "Maternal Angiotensinogen Genotype and Fetal Sex Impact Uteroplacental Function and the Developmental Origins of Stress-Induced Hypertension". PDXScholar, 2018. https://pdxscholar.library.pdx.edu/open_access_etds/4405.
Testo completoAbstract (sommario):
Fetal growth restriction (FGR) is a common and potentially life-threatening complication that affects 5-10% of human pregnancies. Maternal genetic predisposition and fetal male sex are known risk factors, but the underlying mechanisms are unknown. To study a known maternal genetic risk factor and the impact of fetal sex, we employed a published transgenic (TG) mouse model, which was designed to mimic a common human angiotensinogen (AGT) promoter variant associated with a 20% increase in circulating AGT levels. We hypothesized that TG dams would deliver growth restricted pups and that the underlying mechanism would be related to differences in maternal uterine pregnancy-induced vascular remodeling, abnormal blood flow to the placenta, and placental damage. In addition, since growth restricted human males are at an increased risk of developing adult onset hypertension, which has been associated with reduced nephron development, we tested for developmental programming in our mouse model and the impact of fetal sex. Our results show that TG dams have reduced uterine and placental angiogenesis when their pups were males, but relatively normal angiogenesis in the female siblings compared with wild-type controls. The uterine placental bed in TG dams had abnormal pro-angiogenic/anti-angiogenic expression ratios that were related to differences in uterine natural killer cell activation and fetal sex. The abnormal phenotype could be rescued by delivering vascular endothelial growth factor (VEGF) to uterine endothelial cells. Male progeny from TG dams had abnormal kidney epigenetic changes, fewer nephrons as adults, and they developed stress-induced hypertension. We conclude that the combination of maternal genetic risk and fetal male sex affect uteroplacental angiogenesis leading to FGR and the programming of stress-induced hypertension.
43
Muscati, Siham K. (Siham Khalili). "Balance between fetal growth and maternal weight retention : effects of maternal diet, weight and smoking behaviour". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40405.
Testo completoAbstract (sommario):
The interrelation among maternal dietary intake, pregravid weight, amount and pattern of gestational weight gain and cigarette smoking in influencing the balance between fetal growth and maternal postpartum weight retention was in investigated in 1,330 healthy participants in the PEI Nutritional Counselling Program. Among nonsmokers, gestational weight gain was the main predictor of postpartum weight retention and explained 65.3% of its variability, while explaining only 4.7% of infant birth weight variability. Women with higher postpartum weight retention gained more weight during pregnancy and most of the difference between higher and lower weight retention groups occurred in the first 20 weeks. When comparing infant size between smoking and nonsmoking mothers, birth weight increased linearly with maternal weight gain in all weight status groups except in overweight nonsmokers where birth weight reached a plateau at weight gains $>$17 kg. Among smokers, infant length increased at a higher rate with weight gain than nonsmokers. Although higher weight gains seemed to partially mitigate the effect of smoking on the risk of small-for-gestational-age (SGA) infants, such risk remained $>$10% at elevated weight gains among underweight smokers. The effects of smoking in reducing maternal and infant weights were not mediated by lower energy intake, as smokers consumed more energy than nonsmokers after controlling for physical activity and pregravid weight. The independent relative risks of SGA infants due to maternal smoking, pregravid underweight and low weight gain, were 3.23, 1.80 and 1.72 respectively, implying that smoking has the greatest effect on SGA. Based on current smoking prevalence in Canada, the population etiologic fraction of SGA due to the direct effect of smoking is 30.8%; approximately twice that for maternal underweight or low weight gain. Efforts to increase infant birth weight through higher maternal weight gain would require impractically high ene
44
Akyol, Asli. "The effects of cafeteria diet feeding on maternal adaptation to pregnancy, growth and development of fetus and glucose homeostasis later in life". Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/28539/.
Testo completoAbstract (sommario):
Both epidemiological and experimental studies have demonstrated adverse effects of maternal obesity upon both maternal and fetal health. It has been shown that feeding a cafeteria diet in rat pregnancy can induce altered food preferences and greater weight gain in the resulting offspring. This study firstly aimed to examine the effect of diet-induced obesity, or high fat feeding on maternal adaptation to pregnancy and fetal growth. Forty-eight 3-weekold virgin female Wistar rats were randomly divided into two groups fed control (n=24) and cafeteria diet (n=23). 8 weeks later, all rats were mated and after confirming pregnancy half of the rats fed cafeteria diet switched to control, and half of the control rats switched to the cafeteria diet. Maternal cafeteria diet feeding prior to pregnancy resulted in profound adiposity, but did not compromise physiological adaptation to pregnancy or impact upon reproductive success. Maternal cafeteria diet feeding during pregnancy only or maternal obesity induced distinct effects on fetal growth, with pregestational obesity resulting in reduced fetal weight at 20 days gestation. In contrast, cafeteria diet feeding during pregnancy only resulted in increased fetal weight. The main focus of the study was the development of the fetus, and consideration of whether maternal obesity, or cafeteria diet feeding during pregnancy determined body weight, body composition, metabolic biomarkers and glucose homeostasis throughout life. With respect to this point, the same study design was used with additional nutritional challenges during lactation and post-weaning. In contrast to the literature, offspring exposed to cafeteria diet at any stage pre-weaning, showed no evidence of hyperphagia or increased adiposity. Adult offspring exposed to cafeteria diet in early life and weaned onto chow diet, had low fasting glucose and insulin concentrations and were more sensitive to insulin during an i.p. glucose tolerance test. When weaned onto cafeteria diet, offspring exhibited glucose intolerance. There was evidence that rats arrived at a glucose intolerant state via different mechanistic routes which were dependent on the feeding regime during lactation. The data suggested that components of the insulin signalling pathway may be targets for programming by maternal obesity, but that IRS2 and Akt2 do not play major roles. There was also evidence of pancreatic insufficiency in some groups of animals that were fed cafeteria diet during lactation. The observations in this study confirm that maternal over-nutrition and obesity during pregnancy are risk factors for metabolic disturbance in the resulting offspring. The effects on glucose homeostasis were independent of offspring adiposity. However the programming of a glucose intolerant phenotype was dependent upon consumption of cafeteria diet during the post-weaning period.
45
Goddard, Kalanithi Lucy Emily. "Placental Localization and Perinatal Outcome". Yale University, 2008. http://ymtdl.med.yale.edu/theses/available/etd-08132007-124118/.
Testo completoAbstract (sommario):
This retrospective case-control study was designed to investigate the relationship between placental localization and intrauterine growth restriction (IUGR). Pregnant women with an anatomic survey from January 1, 2000, to December 31, 2005, and delivery of the pregnancy at Yale-New Haven Hospital (YNHH) were identified using clinical and billing records. Multiple gestation, fetal anomaly, and incomplete medical information were reasons for exclusion. Cases (N=69) were consecutive pregnancies with evidence of IUGR (estimated fetal weight <10th percentile for gestational age) at last follow-up ultrasound. Randomly selected controls (N=258) from the same time period had no evidence of IUGR. Maternal, ultrasound, delivery, and perinatal data were collected by retrospective medical record review, and IUGR cases and non-IUGR controls were compared using the Students t-test, Wilcoxon test, Chi-square analysis, Fishers exact test, and ANOVA. Placental location was determined from the anatomic survey record (obtained at 18.4 ± 1.2 weeks gestation in the IUGR group and 18.2 ± 1.0 weeks gestation in the control group; P=0.18). Multivariate logistic regression with adjustment for confounders was used to investigate the association between IUGR and placental localization. Consistent with known predictors of IUGR, the IUGR group had a higher proportion of black women (36.4% vs. 19.8%, P=0.03), chronic hypertension (26.0% vs. 3.5%, P<0.001), and hypertensive disorders of pregnancy (36.2% vs. 5.0%, P<0.001). Mean birth weights of IUGR and non-IUGR pregnancies differed by 2 kilograms (3244 ± 625 grams vs. 1277 ± 637 grams, P<0.001). IUGR infants were more likely to receive antenatal steroids, deliver preterm, deliver by cesarean section, and be admitted to neonatal intensive care. In both IUGR and non-IUGR pregnancies, the placenta was most commonly anterior or posterior. Unilateral placentas were three times more common in the IUGR group than in the non-IUGR group (17.4% vs. 5.0%, P=0.01). IUGR pregnancies were over four times as likely as control subjects to have unilaterally-located placentas compared to anterior placentas (OR 4.8, 95% confidence interval, 1.9-11.7). Adjusting for ethnicity, chronic hypertension, and hypertensive disorders of pregnancy did not affect this finding (OR 4.6, 95% confidence interval 1.6-13.5). In conclusion, we compared a group of 69 IUGR pregnancies to 258 non-IUGR controls and found intrauterine growth restriction to be associated with unilateral placentation.
46
Mohamed, Amenah Mahmoud Mustafa. "How safely can we follow up post-term pregnancy with uncertain gestation using amniotic fluid index measurement". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85722.
Testo completoAbstract (sommario):
Thesis (MMed)-- Stellenbosch University, 2013.ENGLISH ABSTRACT: Background: Studies about management of prolonged pregnancy dealt with pregnancy with certain gestational age, confirmed with early ultrasound scans. Objective: The primary aim for the study is to review the current management of uncertain gestational age (GA) post term pregnancy in Tygerberg Academic Hospital (TBH). Women at 42 weeks with an uncertain GA and an amniotic fluid index (AFI) of ≥ 10 cm as well as reassuring cardiotocographs (CTG) would be assessed to determine whether follow up over one week or two weeks are required. Method: A retrospective descriptive study included all patients with an uncertain gestation of 42 weeks referred to TBH. Results: A total of 135 pregnant women were studied. Booking fundal height (BFH) was used to determine GA in 99% and last menstrual period (LMP) in 1% of patients. The time interval between first evaluation at 42 weeks and delivery varies between 0 to 46 days (median 10 days); 104 women delivered vaginally (71% spontaneously, 6% after induction of labour (IOL)); 31 women (23%) by caesarean section; 1 elective, 4 due to cephalopelvic proportion (CPD), 5 had failed IOL, 3 poor progress and 18 fetal distress. Out of the total 11 (8%) women with AFI ≥ 10 had caesarean sections for fetal distress within 2 weeks of the visit at 42 weeks. No neonatal morbidity or mortality was noted in this study. Conclusion: Weekly monitoring with AFI and CTG for women at 42 weeks with unsure gestation is safe. A follow-up following 2 weeks cannot be recommended as 8% of women required caesarean sections within less than 2 weeks due to fetal distress.
AFRIKAANSE OPSOMMING: Agtergrond: Studies oor verlengde swangerskap handel oor swangerskappe met seker swangerskapsduurte, bevestig met vroeë ultraklank skandering. Doelwit: Die primêre doelwit van die studie is om die huidige hantering van verlengde swangerskap met onseker swangerskapsduurte by Tygerberg Hospitaal (TBH) te beoordeel. Vroue wat volgens onseker swangerskapsduurte 42 weke swanger is met ‘n amnionvogindeks (AVI) van >10 en gerusstellende kardiotokogramme (KTG) sal nagegaan word om te bepaal of opvolg oor een of twee weke nodig is. Metode: ‘n Retrospektiewe studie wat alle pasiënte insluit wat na Tygerberg Akademiese Hospitaal verwys word wat ‘n onseker swangerskapsduurte van 42 weke het. Resultate: ‘n Totaal van 135 vroue is bestudeer. Die fundale hoogte is gebruik om swangerskapsduurte te bepaal in 99% van gevalle en die laaste menstruasie in 1%. Die tydsinterval tussen die eerste evaluasie op 42 weke en verlossing wissel tussen 0 en 46 dae (mediaan 10 dae); 104 vroue het ‘n vaginale verlossing gehad (71% met spontane aanvang van kraam, 6% na induksie van kraam); 31 (23%) is met keisersnitte verlos; 1 elektief, 4 as gevolg van skedelbekken disproporsie, 5 gefaalde induksies, 3 swak vordering en 18 met fetal nood. Uit die totaal was daar 11 (8%) vroue met ‘n AVI ≥ 10 wat keisersnitte vir fetale nood binne 2 weke van die besoek op 42 weke gehad het. Geen neonatale morbititeit of mortaliteit het in die studie voorgekom nie. Gevolgtrekking: Weeklikse monitering met AVI en KTG vir vroue wat 42 weke swanger is met onseker swangerskapsduurte, is veilig. Opvolg na 2 weke kan nie aanbeveel word nie want 8% het keisersnitte vir fetale nood gehad na minder as 2 weke.
47
Joyce, Belinda Jane. "Elastin synthesis in the fetal sheep lung in vivo : effects of physical, metabolic and endocrine factors". Monash University, Dept. of Physiology, 2004. http://arrow.monash.edu.au/hdl/1959.1/5263.
Testo completo
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Laing, David. "A semiquantitative and qualitative histopathologic assessment of the effect of type II intrauterine growth retardation on the structure of the carotid bodies in fetuses and neonates". Master's thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/25811.
Testo completoAbstract (sommario):
The major physiological function of the carotid body is to respond to a low partial pressure of oxygen in the systemic arterial blood. The structure and functions of the adult carotid body have been extensively investigated over the past fifteen years. However, the carotid body in children has been relatively neglected with only a handful of studies being performed. To date, no study has been undertaken to investigate the effects of intrauterine hypoxia on the carotid body of foetuses. Clinically, intrauterine growth retardation has been ascribed, amongst other causes, to placental insufficiency that results in chronic hypoxia in the fetus. Intrauterine growth retardation can be divided into two types: - Type I (symmetrical) and type II (asymmetrical). In Type II intrauterine growth retardation, growth retardation does not become clinically evident until the third trimester. There is relative brain sparing with a greater deprivation in the size of abdominal organs, such as the liver and the kidneys. Previous studies have shown that there is no correlation between volume of the carotid body and hypoxia in children. However, Heath et al. made the observation that there are three variants of chief cells (progenitor, light and dark) within the carotid body and that an increase in the relative percentage of the dark subtype is an indicator of hypoxia. Using this observation, the present study set out to test two hypotheses: Firstly, whether the carotid body is functional in utero; and secondly whether there are any objective morphological changes in the carotid bodies of fetuses that have been subjected to intrauterine growth retardation. The carotid bodies from 72 fetuses with a gestational age between thirty and forty weeks were removed from the archived autopsy material, and differential cell counts were performed of the various cells present within the carotid bodies, using haematoxylin and eosin stained sections of the carotid bodies. The cases were assigned to three groups: - I) cases that had clinical and pathological evidence of intrauterine growth retardation, 2) negative controls and 3) positive controls. The three main groups were categorised as follows: -: (1) Intrauterine growth retardation (all cases with a weight for gestational age that is below the tenth centile and a brain to liver ratio of greater than four.) (2) Negative controls (all cases in whom there is a normal weight for age, a brain to liver ratio of less than three and no histological evidence of an episode of significant hypoxia before death). (3) Positive controls (all cases in whom there was clinically significant hypoxia present before death). The groups comprised of: 20 hypoxic positive controls, 15 negative controls, and 16 test cases which had suffered from intrauterine growth retardation. The remaining 21 cases were 7 dysmorphic infants, 3 congenital infection cases (congenital syphilis) and 11 cases that fitted the negative control criteria but had suffered significant hypoxia, thus excluding them from that category. The results showed that no significant difference was present in the percentage of sustentacular cells between any of the three groups. The results of the percentage of dark chief cells were as follows: l) mean percentage of dark chief cells in the intrauterine growth retardation group was 21.1 ±10.9%. 2) mean percentage of dark chief cells in the negative controls was 12.3 ±7.3%. 3) mean percentage of dark chief cells in the positive controls was 21.2 ±9.8%. A significant difference was present between the intrauterine growth retardation cases and the negative controls p=0.013, and between the positive and negative controls p=0.006. The dark chief cell count in the intrauterine growth retardation group showed no significant difference from the positive controls. No age-related difference appeared to be present in any of the groups. The conclusions reached are: a) Clinical hypoxia correlates with morphological changes in the carotid body, manifesting as an increase in the percentage of dark chief cells. b) intrauterine growth retardation cases show similar morphological changes in the carotid body to cases that have suffered from clinical hypoxia. c) therefore, by deduction intrauterine growth retardation fetuses have probably also been exposed to significant hypoxia while in utero. d) the fact that morphological changes in response to hypoxia are occurring in the carotid bodies of fetuses is an indication that the carotid body may be functional in utero. The results of the study indicate that a dark chief cell percentage of greater than 20% indicates that the fetus has been subjected to significant hypoxia, while a percentage of less than 10% indicates that it has not. A percentage of between 10 and 20% is unhelpful in determining whether hypoxia has taken place. The results of this study indicate that histological examination of the carotid bodies in neonates suspected of intrauterine growth retardation could be a useful additional means of assessment.
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Gilfillan, Marlene. "Characteristics of black South African adult and adolescent women who gave premature birth to growth-restricted infants at Kalafong hospital, Gauteng". Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/2740.
Testo completoAbstract (sommario):
Thesis (MNutr (Interdisciplinary Health Sciences. Human Nutrition))--University of Stellenbosch, 2006.INTRODUCTION: The objective of the study was to determine the prevalence of certain known risk factors for intra-uterine growth restriction (IUGR) in women who gave premature birth to growth-restricted infants at a large regional hospital (Kalafong) in the Gauteng province of South Africa and to investigate the possible associations between the presence of various risk factors and the severity of growth restriction found in these infants. METHOD: The study was designed as cross-sectional, descriptive and observational. The subjects included singleton growth-restricted premature infants (n=80), without congenital abnormalities and their mothers (n=80). Anthropometric data [weight, height, mid-upper arm circumference (MUAC) and triceps skinfold thickness (TSF)] were collected from these mothers three to four days post-partum. Infant birth weights were recorded at birth, while the lengths and head circumferences were recorded within 2 days post-partum. Additional information, such as birth spacing, maternal age, smoking habits and alcohol use, was collected by personal interview and blood pressure data and HIV status was obtained from medical records. Data capturing and descriptive statistics were done using Microsoft Excel and comparative analytical statistics were performed with the Statistical Package for the Social Sciences (SPSS), version 12.0. RESULTS: The study demonstrated a high prevalence (69%) of infants born with a birth weight <3rd percentile. In the sample, 81% of the mothers were aged 17-34 years and most (93%) had their children 18 months or longer apart. Malnutrition prevalence was moderate. In 58% of the mothers the BMI was normal (18.5-24.9 kg/m2) and in 47% the upper arm muscle area (UAMA) was between the 10th-85th percentile. Grade III overweight occurred in 3% and TSF ≤5th percentile occurred in 35% of the mothers. About half (51%) of the mothers in the sample population had hypertension during the second trimester of pregnancy. Smoking and alcohol use during pregnancy was rare (1% and 6% respectively) and the prevalence of HIV infection in the mothers was 26%. The prevalence (16%) of Grade II overweight among the mothers of symmetric growth-restricted (SGR) infants was higher than among the mothers of asymmetric growth-restricted (AGR) infants (7%). Of the hypertensive mothers, 55% had infants with SGR compared to 45% with AGR (p=0.47). Although rare, smoking occurred only in mothers with AGR infants (3%). No significant differences were found between the smoking and non-smoking group (p=0.21). Although the use of alcohol was more prevalent at 6% in mothers with SGA infants and 7% in mothers with AGR infants, no significant associations were found (p=0.95). Although not significant (p=0.76), there was a higher prevalence of HIV infection in mothers with SGR infants at 29%, compared to 23% of mothers of AGR infants. CONCLUSION: Although further studies are needed before intervention strategies can be planned and implemented, the findings of this study suggest that apart from the usual factors (maternal age and nutritional status, smoking and alcohol use during pregnancy and birth spacing) that may influence intra-uterine growth, hypertension may contribute greatly to IUGR in this study population.
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Isaacs, Ferial. "An evaluation of fetal growth in human immunodeficiency virus infected women at Khayelitsha and Gugulethu midwifery obstetric units in the Western Cape". Thesis, Cape Peninsula University of Technology, 2006. http://hdl.handle.net/20.500.11838/1547.
Testo completoAbstract (sommario):
Thesis (MTech (Radiography))--Cape Peninsula University of Technology, 2006A prospective cohort study was done on Human Immunodeficiency Virus (HIV) infected and uninfected women attending Khayelitsha Midwifery Obstetric Unit (MOU) and Gugulethu MOU from June 2003 to December 2004, primarily to establish whether there is an association between HIV infection and Intra-uterine growth restriction (lUGR). B-Mode real time ultrasound imaging was used to monitor fetal growth from ±22 weeks to 36 weeks gestational age. Birth weight, gestational age at delivery, gender, placental weight, and maternal complications were also included. Maternal factors considered included age, weight parity, singleton versus multiple pregnancy, previous IUGR or preterm delivery, previous fetal abnormality, social habits viz. cigarette smoking, alcohol and drug use, and vascular disease viz. Diabetes, hypertension, renal disease, cardiac disease and collagen disease. A secondary objective was to establish whether the CD4 T-lymphocyte count possibly modulated the presence of IUGR. All HIV infected women were given antiretroviral therapy according to the standard Protocol of the Provincial Government of Western Cape (2002). The research questions were: • Does maternal HIV infection increase the risk of intrauterine growth restriction and associated preterm delivery? • Does the immune status of (CD4 T-lymphocyte count) of HIV infected pregnant women modulate fetal growth? The primary objective of this study was to establish whether there is an association between HIV infection and IUGR, and hence that HIV infection leads to an adverse perinatal outcome. Ultrasound was used as a diagnostic tool to establish normal or abnormal fetal growth patterns. Anecdotal reports from health workers in the obstetric field suggested that IUGR and preterm delivery may be associated with low birth weight infants in HIV infected pregnant women. However, preterm delivery is associated with various other factors including low socio-economic status (poor nutrition), cigarette smoking, drug and alcohol abuse, previous history of preterm delivery, over distention of the uterus (hydramnios, multiple gestation), premature rupture of membranes, cervical incompetence, vaginal infections (bacterial vaginosis) and maternal disease e.g. hypertension, heart disease (Lizzi, 1993: Symmonds, 1992; Odendaal et aI, 2002). HIV is now thought to be an added factor. Afier doing a systematic review and meta-analysis of 31 studies, Brocklehurst and French (1998) reported that there is an association (although not strong) between HIV infection and adverse perinatal outcome in developed countries; but in developing countries, there is an increased risk of infant death. By excluding or controlling for confounding variables that could affect fetal growth, this study aimed to determine whether there is a significant association between HIV and fetal growth by comparing fetal growth in HIV infected and uninfected women from midsecond trimester to the time of delivery. A secondary objective was to establish whether there is an association between the immune status (CD4 T-lymphocyte count) of the mother and IUGR. The immune status of the mother is probably one of the most important factors affecting the fetus and perinatal outcome. As the mother's viral load increases, her immune system is increasingly compromised, resulting in the occurrence of HIV-related diseases, and a concurrent increase in fetal complications. In this study a CD4 T-lymphocyte count was used to assess the level of immunodeficiency of all the HIV infected participants. Ideally the test should have been done each time the participant was scanned so that the CD4 T-lymphoc)1e count could be monitored simultaneously with the fetal growth parameters, however due to financial constraints and ethical considerations, one test was done on each HIV infected women. This study was based at two MOU's where different antiretroviral therapy (ARVT) regimens were used. The one MOU offered Zidovudine (ZDV) to mothers from 34 weeks gestation to the onset of labour, and the other MOU offered Nevirapine (NVP) as a single dose to the mother at the onset of labour and to the neonate within 72 hours of birth (Provincial Government Western Cape, 2002). This presented an opportunity to compare two groups of HIV infected women on different regimes. The intention was to establish whether ZDV had an adverse effect on fetal growth and resulted in low birth weight. However, 6 months after the study started a revised Prevention of Mother to Child Transmission (PMTCT) Protocol was implemented where women at both MOU's received the same ARVT i.e. ZDV and NVP. This objective was therefore abandoned due to a change in the PMTCT Protocol in the Western Cape. The study was based at two Midwife Obstetric Units (MOU) in the Western Cape where the prevalence of HIV in pregnant women is relatively high i.e. 20 - 24 % (Mother-to-child transmission Monitoring Team, 2001), viz. Gugulethu MOU and Khayelitsha MOU. A prospective cohort study was done with the intention of recruiting a sample of 400 pregnant women, 200 HIV infected and 200 uninfected. The actual sample size was 415. The study group was 194 HIV infected women and the control group was 221 uninfected women. Confounding variables such as cigarette smoking, alcohol and drug abuse. multiple gestation. grand multipara pregnancy, history of IUGR or preterm delivery. fetal abnormality detected at the time of the first scan in the current pregnancy, and maternal vascular disease - were excluded. Confounding variables such as maternal age, maternal weight and gestational age were controlled. Ultrasound imaging was used as a diagnostic tool to establish normal and abnormal fetal growth patterns. A B-mode real time ultrasound unit was used to confirm the gestation age and rule out any obvious fetal abnormalities at 20-24 weeks gestation. Fetal growth scans were done at 28 weeks, 32 weeks and 36 weeks gestation to compare fetal growth patterns in the study and control groups. Fetal biometry used to monitor fetal growth included biparietal diameter (BPD), head circumference (HC), femur length (FL), abdominal circumference (AC) and estimated fetal weight (EFW). Amniotic fluid index (AFI), placental thickness & placental grading were also included. The following variables were analyzed post delivery: • Gestation age at delivery: Normal term delivery is considered to be at 37 - 42 weeks and premature delivery is considered to be less than 37 weeks gestation. The HIV infected and uninfected groups were compared to assess if there \vas a significant difference in the number of preterm deliveries. • Birth weight: The HIV infected and uninfected groups were compared to assess if there was a significant difference in the number of infants with low birth weight. • Perinatal complications: The HIV infected and uninfected groups were compared to assess if there was a significant difference in the number of perinatal complications and to assess if there was an association between the immune status (CD4 T-lymphocyte count) of HIV infected women and perinatal complications. Appropriate ethical principles in medical research were applied. The participant's autonomy, rights and best interests were always considered a priority. Informed consent was obtained from all the participants. Strict confidentiality was adhered to regarding any data collected throughout the study. The Research Ethics Committees at Cape Peninsula University of Technology and University of Cape Town granted ethics approval for the study. Statistical analysis was performed using the statistical package SPSS 12.0.