Brain cerebrospinal fluid (CSF) bulk flow is maintained thanks to a balance between CSF secretion from the choroid plexus and CSF absorption by arachnoid villi, where it drains into nearby blood vessels, thereby reaching the general blood circulation. Congenital hydrocephalus starts during the first trimester of pregnancy with impeded CSF flow, and consequent CSF build-up within the brain ventricles. This event is followed by CSF compositional changes, increased intracranial pressure, and, if untreated, brain damage and fetal death. Previous research has revealed a unique folate delivery system which serves the developing cerebral cortex. Abnormal folate provision due to impairment of this system was directly connected to a decrease in a CSF folate enzyme: 10-Formyl-Tetrahydrofolate dehydrogenase (FDH). In light of these findings, low FDH was linked with folate deficiency and the poor cortical development found in congenital hydrocephalus. In this context, investigations were carried out to ascertain whether folates in the presence and absence of the folate enzyme FDH are beneficial for fetal brain development. The current study also aims to investigate the FDH -folate delivery system in the fetal brain in order to understand its role in CNS development and its relationship to currently known folate transport mechanisms (FRα). Furthermore, we hypothesize that folates may prevent congenital hydrocephalus through a re-establishment of CSF drainage and flow circulation at the level of the arachnoid membrane/villi. This assumption implies that the leptomeninge arachnoid may also be dysfunctional in the hydrocephalic brain due to a variation in hydrocephalic CSF composition (folates). Finally, an overall metabolic pathway analysis of the constituents uniquely present in abnormal CSF, hence missing in normal CSF, and vice versa, was carried out to establish associations with suggested activated and inactivated biological processes during congenital hydrocephalus.

Barker's "fetal origin hypothesis" advocates that the diseases in later life originate through adaptations that fetus makes when it is undernourished. These adaptations, whether cardiovascular, metabolic, or endocrine, permanently change the structure, and functions of the body, and pave the road to chronic killer diseases in later life, such as; coronary heart diseases, related disorders, stroke, diabetes, and hypertension. The main objective of the study, both prospective, and retrospective, covering the subjects from 0 to 1 year, and 3 to 15 years, respectively, is to test the Barker "fetal origin hypothesis" that nutrition in early life does influence the disease pattern in later life. The research is specifically designed to study the relationship between infant body size, placental weight, blood pressure, and lipid profile in late infancy; and whether or not the relationship between high blood pressure, and low birthweight is initiated in uterus, or during the infancy. The prospective studies were carried out in Prince Salman Bin Abdulaziz Hospital in Riyadh, KSA. The sampling was performed systematically. Every fifth child born in the delivery room was selected in the obstetric ward. A total of 1026 neonates were included in the prospective studies. The retrospective studies were conducted in Deraya Primary Health Care Centre, and data were collected from the medical record department, which included 1505 subjects, aged 3 to 15 years. The babies with major congenital malformations were excluded both studies included questionnaires, anthropometric measurements, and critical evaluation of haematological and biochemical parameters. The data collected, both prospective and retrospective and retrospective studies, were categorised, analysed, and statistically interpreted by using the Statistical Package for Social Science SPSS/PC+V9.0. Normal distributions of data were confirmed by using the Kolmogorow-Smirnow Test. In all cases, significance was assumed at P < 0.05. The major findings do support Barker's epidemiological data, and evidences. Although, it is still somewhat too early, and premature to confirm these findings, due to the length of period covered, the data presented, both prospective and retrospective, do point out, and lead to the following major conclusions: Chronic diseases are being imprinted "Programmed" in feto-placental unit during pregnancy, and infancy, there is indeed a strong association between birthweight, especially, low birthweight, and placental weight, blood pressure, lipid metabolism in early infancy, and in childhood. Low birthweight, <2500gms is strongly associated with elevated systolic blood pressure, and low birthweight infants, if survived, are predisposed to inevitable disabilities of all kinds, and chronic diseases in later life.

Insufficient maternal folate during pregnancy increases the risk of the baby being small for gestational age (SGA). Studies in teenagers, a population vulnerable to folate deficiency and SGA birth, have shown that low maternal folate status is associated with impaired placental cell turnover and reduced transport suggesting placental dysfunction underlies SGA in maternal folate deficiency. Mechanisms through which folate-depletion compromises placental function are currently unknown. In non-placental cells, folate modulates microRNAs (miRs), post-transcriptional regulators of cellular functions. Expression of miRs is altered in placentas of SGA compared to normally grown babies but there are no data on differential miR expression or regulation in placentas from folate deficient women. This PhD investigated the hypothesis that placental dysfunction observed in folate deficient women is mediated by altered miR expression. Three placental preparations were compared (villous tissue in explant culture, BeWo choriocarcinoma cells and isolated cytotrophoblast cells) to determine the optimum in vitro system to study the direct effects of folate deficiency. In cytotrophoblast cells, folate deficiency significantly elevated apoptosis and reduced the activity of the system A amino acid transporter, consistent with observations in the placentas of folate-deficient teenagers. The reduction in system A activity by low folate was not associated with altered mRNA expression for the isoforms of system A, implicating an effect of low folate on post-translational regulation of the nutrient transporter. Targeted examination of villous tissue from teenagers with low folate status identified up-regulation of miR-222-3p a folate-sensitive miR. An unbiased miR array identified up-regulation of a further 16 miRs suggesting that maternal folate deficiency in vivo results in aberrant placental miR expression. Bioinformatic analysis of the folate sensitive miRs predicted gene targets known to be altered in placentas from SGA pregnancy that were likely to alter placental function. Two miRs altered in placentas from women with low folate status, miR-30e-3p and miR-34b-5p, were also significantly altered in folate deficient cytotrophoblasts confirming a direct effect of folate on trophoblast miR expression. Inhibition of these miRs in vitro had no effects on placental functions that are altered in vivo in folate-deficient women. Gene array and in silico analysis identified functional endpoints affected by these folate sensitive miRs, including cell signalling for proliferation and survival and oxidative stress, which might contribute to placental dysfunction in folate deplete women. Overall, this study has demonstrated for the first time that folate deficient conditions can directly alter trophoblast system A transport and cell survival and thus could contribute to the increased susceptibility to SGA births in folate deficient women. It has also contributed to the knowledge that miR expression is differentially altered in placentas exposed to folate-deficient versus sufficient conditions in vivo and that miRs are directly altered by folate depletion in vitro. These studies provide the foundation for future research to define the functional consequences of altered expression of folate-sensitive miRs and their target genes to explain how altered miRs could be affecting placental function resulting in development of SGA.

Fetal growth restriction (FGR) signifies that the fetus has not achieved its growth potential and is associated with increased perinatal mortality and morbidity. The exact aetiology of FGR, in the absence of any identifiable fetal and maternal factors, remains unclear and is attributed to placental insufficiency. The FGR placenta has a characteristic phenotype including: increased resistance in the fetoplacental circulation, an alteration in trophoblast cell turnover and reduced activity of placental nutrient transport systems, the best characterised being the amino acid transporter, system A. The placenta strongly expresses the cortisol inactivating enzyme, 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2). 11β-HSD2 activity was reduced in placentas from pregnancies complicated by FGR, suggesting increased exposure of the fetoplacental unit to maternal cortisol. In animal models, excessive exposure to glucocorticoids (GCs) is associated with a reduction in both fetal and placental weight. This reduction in placental weight was associated with abnormalities in placental function, consistent with those observed in the FGR placenta. This PhD investigated whether excess GC exposure during pregnancy is responsible placental insufficiency in human pregnancies and tested the hypotheses that excess GC exposure adversely affects placental vascular tone, trophoblast cell turnover and activity of the amino acid transporter, system A. Term placentas were collected from uncomplicated pregnancies and first trimester placental samples were obtained following elective surgical termination of pregnancy. Wire myography was used to explore the acute and chronic effects of GCs on term chorionic plate artery (CPA) function. The impact of GC treatment on trophoblast cell turnover in both first trimester and term placenta was investigated using the placental explant system. The effect of GCs on the activity of the system A transporter was also investigated in term explants and in isolated cytotrophoblasts where the expression of 11β-HSD2 was reduced using siRNA. Gene microarray studies on first trimester placental explants treated with GCs were utilised to identify genes regulated by GCs. Blunted constriction to thromboxane A2 was observed following acute GC treatment, whilst chronic exposure resulted in enhanced vasoconstriction, mimicking the altered reactivity of CPAs from pregnancies complicated by FGR. GC excess in first trimester placental explants increased apoptosis and decreased proliferation, thereby replicating the disordered turnover of the trophoblast observed in FGR placentas. No demonstrable effect was observed in cell turnover or system A activity in term placental explants treated with GCs, however, these experiments were hindered by the in-vitro regeneration of the syncytiotrophoblast in the model employed. The attenuation of 11β-HSD2 activity observed in FGR placentas was replicated in term primary cytotrophoblasts utilising siRNA to knock-down expression of 11β-HSD2. Preliminary results suggested an increase in system A activity in response to cortisol. Gene microarray studies identified a significant number of genes (~500) that were regulated by dexamethasone, confirming that GCs have an impact on many aspects of placental function. Potential mediators for the characteristic features of the FGR placenta replicated here in response to GC treatment were identified and validated at the mRNA level. The studies described in this thesis support the hypotheses that GC excess within the placenta contributes to the development of raised vascular resistance in the fetoplacental circulation and the disordered trophoblast turnover in placentas from pregnancies complicated by FGR. However, with the preliminary studies performed, the hypothesis that elevated levels of GCs contribute to the reduced placental amino acid transfer by the system A transporter in the FGR placenta can not be confidently disproven.

No description available.

Monitoring of women in labour is an important aspect of the practice of the health care professionals working in the labour ward. The pregnancy of a woman mightappear to be normal but it is not possible to predict the positive outcome of labour until the baby is born because foetal distress can occur suddenly or other problems can arise during the course of labour. Doctors need to closely monitor the progress of labour of all the women regardless of whether he pregnancy is rated low risk or not. The use of Cardiotocography (CTG) during labour thus becomes critical. In the current study the perceptions of the doctors working in labour ward units will be explored and described in order to recommend activities that could optimize the use of CTG by doctors as an intrapartum monitoring tool. A qualitative research design will be used and the data collection method will be by means of semi-structured audio-taped one-on-one interviews.

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.

To study the effect of maternal nutrition on fetal protein synthesis, isotopic kinetic studies were undertaken in which indwelling catheters were implanted in the inferior vena cava and saphenous vein of ovine fetuses as well as the jugular vein and femoral artery of ewes at 120-130 days of gestation Following a five day post surgical recovery period an 8h continuous infusion of L-[2,3,5,6-³H] or L-[U-¹⁴ C] tyrosine was made into the fetus and ewe simultaneously. An enzymatic procedure specific for L-tyrosine was used to measure the plateau specific activity in fetal and maternal plasma. Using these values the net placental transfer, endogenous production and net utilization of tyrosine by the fetus were determined employing a two pool kinetic model. For determining the fractional protein synthetic rates in individual tissues the ewes were sacrificed and the fetuses obtained by laparotomy immediately following the continuous infusion of labelled tyrosine. The effect of starvation on tyrosine transfer across the placenta and protein synthesis by the fetus was studied by repeating the above procedures in ewes starved for 48h. Values for the net placental transfer, endogenous production and net utilization of tyrosine were 5.14, 1.29 and 6.42 mmol/d/kg respectively for fetuses of fed ewes, whereas, these values were -0.29, 4.53 and 3.88 mmol/d/kg in fetuses of starved ewes. The plasma concentrations (mg%) of glucose, alpha amino nitrogen and lactate in the fed ewes were 60.18, 10.68 and 5.58 versus 43.66, 7.80 and 7.41 in starved ewes. Glucose, alpha amino nitrogen and lactate values were also seen to change in the fetus from 12.55, 13.38 and 12.98, respectively in the fed versus 8.18, 11.55 and 15.08 in fetuses of starved ewes. The fetal tyrosine net utilization values, corrected for oxidative loss of 5.2%, were used to calculate the whole body protein synthetic values. From an average tyrosine content of carcass protein of 15.71 mmol/kg, the whole body protein synthetic rates were 63 g/d/kg in the fed versus 25 g/d/kg in the starved fetuses. Fetal tissue fractional protein synthetic rates were also affected by maternal starvation. The fractional synthetic rates (%/day) for liver, kidney, lung, heart and skeletal muscle were 78%, 45%, 65%, 14% and 26% for fed versus 12%, 22%, 23%, 11% and 10%/d for the fetuses of starved ewes. The data demonstrate that maternal feed deprivation reduces protein synthesis in the fetus. / Land and Food Systems, Faculty of / Graduate

Orientadores: Renato Passini Junior, Eduardo Mello de Capitani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-04T01:25:17Z (GMT). No. of bitstreams: 1 Rosalem_Alvaro_D.pdf: 403809 bytes, checksum: d10b22265e90b9607f1056eb78498165 (MD5) Previous issue date: 2004 / Resumo: O objetivo deste estudo foi avaliar a associação entre fatores ambientais de risco e níveis séricos de chumbo com a ocorrência de aborto espontâneo, em gestantes atendidas no período de fevereiro de 2003 a julho de 2004, no Hospital Maternidade Leonor Mendes de Barros, em São Paulo. Inicialmente foi feita análise de fatores de risco ambientais de exposição ao chumbo, seguida da avaliação da plumbemia, em 190 mulheres com abortamento espontâneo (casos) e 190 mulheres com feto vivo (controles), que aceitaram participar do estudo. Os sujeitos foram entrevistados utilizando-se um questionário estruturado e submetidos à coleta de sangue para determinação da plumbemia. Foram analisadas variáveis sociodemográficas, ambientais, ocupacionais, hábitos e vícios relacionados com a exposição ao chumbo, bem como a história obstétrica e a plumbemia. Para dosagem de chumbo plasmático foi utilizada a técnica de espectrofotometria de absorção atômica. A análise estatística incluiu o cálculo de média e desvio padrão para as variáveis numéricas contínuas, testes não paramétricos de Mann-Whitney e de Wilcoxon, Odds Ratio e seu correspondente IC 95% para identificar a associação entre fatores de exposição ao chumbo e abortamento, e análise multivariada. Dentre os fatores ambientais de exposição ao chumbo estudados, somente o consumo de alimentos enlatados [OR=3,80 (IC 95%=1,38¿12,20)] e o trabalho remunerado [OR=2,52 (IC 95%=1,29¿5,28)], associaram-se ao abortamento. A média da plumbemia foi de 2,71µg/dl para os casos e de 2,39 µg/dl para os controles, sem diferença estatisticamente significativa. Concluiu-se que não houve influência significativa dos fatores ambientais de exposição ao chumbo estudado e que a plumbemia não foi diferente entre mulheres com e sem abortamento. A média de plumbemia no 3º trimestre em gestantes não ocupacionalmente expostas foi de 2,24 µg/dl, valor que pode ser utilizado como referência em estudos envolvendo determinação de chumbo plasmático na gravidez / Abstract: The objective of this study was to evaluate the association between environmental risk factors and blood lead levels with the occurrence of spontaneous abortion in pregnant who were assisted in the period from February 2003 to July 2004 at Maternity Hospital Leonor Mendes de Barros, in São Paulo. The study had two designs: case-control study to evaluate environmental risk factors of exposition to the lead and cross section, which evaluated the blood lead level of population who had been studied. It has evaluated 190 women with spontaneous abortion (cases) and 190 women with alive fetus (controls), who accepted to participate of this study. The subjects were interviewed using a specific questionary prepared for this study and submitted a blood sample in order to determine the blood lead level. They were analyzed variables such as: social-demographics, environmental, occupational, behaviour and chemical addictions related to lead exposure as well obstetrical history and the blood lead level. Blood lead determinations were carried out using atomic absorption spectrophotometry. Statistical analysis included mean determination and standard deviation for continuous numerical variables, Mann-Whitney and Wilcoxon non-parametric tests, Odds Ratio plus its correspondent 95% CI to identify the association between factors of exposition to the lead and abortion, and multivariate analysis. Among environmental factors related to lead exposure, just the consumption of canned food [OR=3.80 (IC95%=1.38-12.20)] and paid work [OR=2.52 (IC95%=1.29-5.28)] were associated to the abortion. The mean blood lead level was 2.71µg/dl to cases group and 2.39µg/dl to controls group without significant statistically difference. We concluded that did not have significant influence of environmental factors related to lead exposure studied and the blood lead level was not different among women with or without abortion. The mean blood lead level in the third quarter in pregnant not professionally exposed were 2.24µg/dl, this value could be used as reference in a studies involving determination to blood lead in the pregnancy / Doutorado / Ciencias Biomedicas / Doutor em Tocoginecologia

Americans consume three percent more total daily calories from sugar than current recommendations. Maternal diets high in sugar can cause obesity and diabetes mellitus. Objectives were to compare supplemental dietary sucrose to a protein alternative on maternal health and fetal programming utilizing a sow biomedical model. Pregnant sows (Landrace × Yorkshire, average BW = 222 ± 35 kg, n = 21) were fed a corn-soybean meal-based diet (CSM) at one percent BW at 0700 h daily from d 29 (± 1.47) to 111 (± 0.58) of gestation. Sows were randomly assigned to dietary supplement treatments: 126 g CSM (CON, n = 5), 110 g cooked ground beef (BEEF, n = 6), 85.5 g sucrose (SUCR, n = 5), or the combination of 54.8 g BEEF and 42.7 g SUCR (B+S, n = 5). Dietary supplements were fed three times daily from d 40 to 110 (± 0.58) of gestation. A repeated measures design was modeled using the MIXED procedure of SAS. Dietary treatment did not influence gestational BW (P ≥ 0.99), subcutaneous fat depth (P ≥ 0.09), blood chemistry panel (P ≥ 0.21), or total-, HDL-, or LDL-cholesterol, triglyceride, insulin, or C-reactive protein serum concentrations (P ≥ 0.07). Dietary treatment did not influence sow organ or lean tissue weight (P ≥ 0.42). Compared to CON, BEEF fetuses had increased BW (P = 0.01), crown to rump length (P = 0.01), nose to crown length (P < 0.01), heart girth (P = 0.02), and abdominal girth (P = 0.05). Dietary treatment did not influence fetal growth characteristics of median weight male and female fetuses (P ≥ 0.23). Compared to BEEF, SUCR fetuses had heavier liver weights (P = 0.04). Dietary treatment by sex interaction occurred for fetal kidney weight with BEEF males having heavier kidney weights compared BEEF females (P = 0.03). Dietary treatment did not influence other fetal organ or lean tissue weights (P ≥ 0.09). These results suggest beef or sucrose supplementation at 1.49 or 1.16 grams per kilogram BW per day, respectively, from day 40 to 110 of gestation had minimal impact on maternal health and fetal development. / North Dakota Beef Commission; Topigs Norsvin; and North Dakota State University Agricultural Experiment Station