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Fetal ECG Extraction Using Nonlinear Noise Reduction and Blind Source SeparationYuki, Shingo 08 1900 (has links)
The fetal electrocardiogram contains within it, information regarding the health of the fetus. Currently, fetal ECG is recorded directly from the scalp of the baby during labour. However, it has been shown that fetal ECG can also be measured using surface electrodes attached to a pregnant mother's abdomen. The advantage of this method lies in the fact that fetal ECG can be measured noninvasively before the onset of labour. The difficulty lies in isolating the fetal ECG from extraneous signals that are simultaneously recorded with it. Several signal processing methodologies have been put forth in order to extract the fetal ECG component from a mixture of signals. Two recent techniques that have been put forth include a scheme that has previously been used to nonlinearly reduce noise in deterministically chaotic noise and the other uses a blind source separation technique called independent component analysis. In this thesis, we describe the significance of the fetal electrocardiogram as a diagnostic tool in medicine, a brief overview of the theory behind the nonlinear noise reduction technique and blind source separation, and results from having processed synthetic and real data using both techniques. We find that although the noise reduction technique performs adequately, the blind source separation process performs faster and more robustly against similar data. The two techniques can be used in tandem to arrive at an approximate fetal ECG signal, which can be further analyzed by calculating, for example, the fetal heart rate. / Thesis / Master of Engineering (ME)
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Effects of low-dose ionizing radiation in utero on postnatal growth and cardiovascular physiology in BALB/cJ micePreston, Jessica January 2019 (has links)
Diagnostic radiation is typically avoided during pregnancy, as the effect of low-dose radiation exposure on the fetus is uncertain. The objective of this study was to determine if ionizing radiation exposure during late fetal development would cause an adverse intrauterine environment, and lead to growth restriction of offspring and a hypertensive phenotype later in life. To study this, pregnant BALB/cJ mice were exposed to ionizing radiation at 5, 10, 50, 100, 300 or 1000 mGy on gestational day 15. Offspring were weighed weekly from the age of weaning until a mature age of 16 weeks. Cardiovascular effects were assessed every other week via heart rate and blood pressure measurements using tail plethysmography. The expression of genetic markers for endothelial dysfunction, inflammation, mitochondrial capacity, and regulation of the oxidative stress response in the aorta and heart for the 1000 mGy was assessed from tissue collected at 17 weeks of age. We observed no effects of low to mid dose (5-300 mGy) radiation on offspring growth and blood pressure. Growth restriction was observed in male and female offspring exposed to high-dose radiation (1000 mGy). In the heart, there was no observed effect on mitochondrial capacity and oxidative stress response genes. In the aorta, we observed decreased TNF-α expression in male offspring, which may be linked to the growth restriction but was not considered a sign of cardiovascular dysfunction. There were no observed effects of exposure to 1000 mGy on cardiovascular function. This study provides knowledge on the possible effects of radiation on in utero development, which broadens the knowledge on the range of stressors capable of affecting offspring growth and development. / Thesis / Master of Science (MSc)
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Description of fetal heart rate patterns at 20 to 24 weeks gestationHofmeyr, Franelise 12 1900 (has links)
Thesis (MMed)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Introduction - Accurate computerized analysis of the fetal heart rate (FHR) pattern has become more feasible and clinically relevant in recent years. Taking into account advances in neonatal care resulting in a declining lower limit for fetal viability as well as research into fetal effects of maternal high risk behaviour and escalating intra-uterine exposure to harmful toxins and drugs, fetal heart rate patterns need to be more accurately described in earlier gestations than what is currently available in literature. With advancing technology it is becoming possible to accurately record and interpret the FHR patterns from gestations as early as 20 weeks' gestation. By using the Monica AN24 transabdominal electrocardiographic fetal monitor and product specific software, we analysed early FHR patterns according to the Dawes-Redman criteria, as used in later gestations. Methods - The aim of our study was to describe patterns of FHR (short-term variability, basal heart rate, accelerations and decelerations) at 20-24 weeks' gestation. Physiological data were obtained from the routine second trimester fetal assessment by the Monica AN24 monitor as used in the Safe Passage Study. As of December 31, 2009, 411 participants completed their first fetal assessment and met our inclusion criteria. Because our aim was the description of patterns in pregnancies with a normal outcome, we excluded all adverse neonatal outcomes, preterm deliveries, babies with low birth weights as well as cases where delivery data were lost. After recordings of poor technical quality were also removed from our data pool, 281 recordings remained for analysis. Results - Distinct FHR patterns and quantifiable parameters of heart rate variability were consistently observed. In contrast to what has previously been published, accelerations of the FHR and reassuring baseline variation are present from as early as 20 weeks. Conclusion - Information from this study provides an important foundation for further studies of early FHR patterns and it will help us better assess the fetus at a crucial age for indicators of good outcome at early delivery. / AFRIKAANSE OPSOMMING: Inleiding - Akkurate gerekenariseerde ontleding van die fetale hartpatroon het in die afgelope paar jaar meer tegnologies haalbaar met toenemende kliniese toepassing geword. Tans ervaar ons besondere vooruitgang in neonatale sorg en dus dalende grense vir vroeë lewensvatbaarheid in kliniese praktyk. Daar is ook 'n toename in navorsing oor moederlike hoë risiko gedrag tydens swangerskap en die effek hiervan op die ontwikkeling die fetus asook die neonatale uitkomste. Akkurater beskrywing van fetale hartpatrone in vroeëre gestasies as wat huidiglik in die literatuur beskikbaar is, is dus genoodsaak om die effekte van blootstelling op die fetus waar te neem. Met vooruitgang in tegnologie is dit nou moontlik om deur nie-indringende elektrokardiografie, fetale hartpatrone te registreer en te interpreteer van so vroeg as 'n swangerskapsdurte van 20 weke. Deur die gebruik van die Monica AN24 transabdominale monitor en produk-spesifieke programmatuur, kon ons vroeë fetale hartpatrone ontleed volgens die Dawes-Redman kriteria wat gewoonlik in later swangerskapsduurtes gebruik word. Metodes - Die doel van ons studie was die beskrywing van verskeie fetale hartpatrone (naamlik korttermyn variasie, basale hartspoed, versnellings asook vestadigings) rondom 20 – 24 weke swangerskapsduurte.
Fisiologiese data is in die tweede trimester verkry deur die Monica AN24 monitor, soos gebruik word in die voortgaande Veilige Geboorte Studie by Tygerberg hospitaal. Tot en met 31 Desember 2009, het 411 deelnemers hulle eerste fetale evaluasie vir die Veilige Geboorte Studie gehad en ook voldoen aan die insluitingskriteria van hierdie projek.
Aangesien ons fokus die beskrywing van hartpatrone in normale swangerskappe was, het ons alle nie-wenslike neonatale uitkomste, voortydse verlossings, babas met lae geboorte gewig asook gevalle waarvan die geboortedata nie beskikbaar was nie, uitgesluit. Alle opnames met sub-standaard tegniese kwaliteit is ook verwyder uit ons finale data vir ontleding, wat ons met 281 opnames gelaat het vir hierdie studie. Resultate -
Duidelike fetale hartpatrone en meetbare afmetings is deurgangs opgemerk. In teenstryd met wat voorheen gedokumenteer is, is die teenwoordigheid van versnellings asook gerusstellende basislyn variasie meetbaar vanaf 20 weke gestasie. Samevatting - Informasie vanaf hierdie studie verskaf 'n belangrike grondslag vir verdere projekte in die ontleding van fetale hartpatrone met die fokus op ondersoek van vroeë voorspelling van goeie neonatale uitkomste.
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The effect of misoprostol on fetal heart rate parameters during induction of labour from 38 weeks gestation : a retrospective auditFeketshane, Anthony M. 12 1900 (has links)
Thesis (MMed)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: Misoprostol is often used for the purpose of induction of labour. However, its effect on fetal heart rate has not been systematically studied. Objective
To assess the effect of misoprostol on fetal heart rate parameters during induction of labour from 38 completed weeks in women with previous intrauterine death or postterm pregnancy.
Study design
A retrospective descriptive study of 127 women for a period of 18 months.
Method
Women who underwent induction of labour with misoprostol for either previous intrauterine death or postterm pregnancy at Tygerberg hospital were eligible.
The selected process of induction of labour happened according to the departmental protocol. The primary outcomes were changes in fetal heart rate (variability, accelerations and decelerations) pre-and post-administration of misoprostol. Secondary outcomes were neonatal highcare or intensive care unit (ICU) admissions.
Results
There was no statistical difference in the mean fetal heart rate and baseline variability in relation to time recordings after administration of misoprostol. There were no statistically significant differences in the distribution of accelerations and decelerations in different time intervals before and after administration. There were more reactive patterns at all time intervals after the administration of misoprostol, but these differences did not quite reach statistical significance. In both study groups no neonatal complications or intensive care admissions were reported.
Conclusion
In the absence of contra indications, 50mcg of oral misoprostol can be given to mothers for induction of labour as no harmful fetal heart tracing abnormalities were found for 45 minutes; however large prospective randomized controlled trials are still needed to confirm effectiveness and evaluate further maternal and neonatal safety issues. Optimal dose and frequency also still need robust interrogation. Based on this thesis it does appear that misoprostol is probably not harmful to the fetus under these circumstances. / AFRIKAANSE OPSOMMING: Misoprostol word dikwels gebruik vir induksie van kraam. Die effek daarvan op fetale hartspoed is egter nie sistematies ondersoek nie.
Doel
Om die effek van misoprostol op fetale hartspoedparameters gedurende die induksie van kraam van 38 voltooide weke in vroue met vorige intra-uteriene dood or oortyd swangerskap te evalueer.
Studei-ontwerp
„n Retrospektiewe beskrywende studie van 127 vroue oor „n periode van 18 maande.
Metode
Vroue wat induksie van kraam met misoprostol ondergaan het vir of vorige intra-uteriene dood of oortyd swangerskap by Tygerberg Hospitaal is ingesluit.
Die proses van induksie van kraam is volgens departementele protokol uitgevoer. Die primêre uitkomste was veranderinge in fetale hartspoed (variasie, versnellings en verstadigings) pre- en post-toediening van misoprostol. Neonatale hoësorg of intensiewe sorg toelatings was sekondêre uitkomste. Resultate
Ons het geen statistiese verskille in gemiddelde fetale hartspoed en basislynvariasie in verhouding tot die tyd na toediening van misoprostol gevind nie. Daar was geen statisties betekenisvolle verskille in die verspreiding van versnellings en verstadigings in verskillende tydsintervalle nie. Daar was meer reaktiewe patrone gedurende alle tydsintervalle na die toediening van misoprostol, maar hierdie verskille was nie statisties betekenisvol nie. In beide studiegroepe was daar geen neonatale komplikasies of intensiewe sorg toelatings nie.
Gevolgtrekking
In die afwesigheid van kontra-indikasies kan 50 mcg misoprostol aan moeders toegedien word vir induksie van kraam aangesien geen skadelike fetale hartsped abnormaliteite gevind is nie. Groot prospektiewe gerandomiseerde gekontroleerde studies word steeds benodig om effektiwiteit te bevestig en om moederlike en fetale veiligheidskwessies verder te evalueer. Optimale dosis en frekwensie benodig ook robuuste ondersoek. Gebaseer op hierdie tesis kom dit voor of misoprostol waarskynlik nie skadelik vir die fetus onder hierdie omstandighede nie.
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Automatic measurements of femoral characteristics using 3D ultrasound images in uteroYaqub, Mohammad January 2011 (has links)
Vitamin D is very important for endochondral ossification and it is commonly insufficient during pregnancy (Javaid et al., 2006). Insufficiency of vitamin D during pregnancy predicts bone mass and hence predicts adult osteoporosis (Javaid et al., 2006). The relationship between maternal vitamin D and manually measured fetal biometry has been studied (Mahon et al., 2009). However, manual fetal biometry especially volumetric measurements are subjective, time-consuming and possibly irreproducible. Computerised measurements can overcome or at least reduce such problems. This thesis concerns the development and evaluation of novel methods to do this. This thesis makes three contributions. Firstly, we have developed a novel technique based on the Random Forests (RF) classifier to segment and measure several fetal femoral characteristics from 3D ultrasound volumes automatically. We propose a feature selection step in the training stage to eliminate irrelevant features and utilise the "good" ones. We also develop a weighted voting mechanism to weight tree probabilistic decisions in the RF classifier. We show that the new RF classifier is more accurate than the classic method (Yaqub et al., 2010b, Yaqub et al., 2011b). We achieved 83% segmentation precision using the proposed technique compared to manually segmented volumes. The proposed segmentation technique was also validated on segmenting adult brain structures in MR images and it showed excellent accuracy. The second contribution is a wavelet-based image fusion technique to enhance the quality of the fetal femur and to compensate for missing information in one volume due to signal attenuation and acoustic shadowing. We show that using image fusion to increase the image quality of ultrasound images of bony structures leads to a more accurate and reproducible assessment and measurement qualitatively and quantitatively (Yaqub et al., 2010a, Yaqub et al., 2011a). The third contribution concerns the analysis of data from a cohort study of 450 fetal femoral ultrasound volumes (18-21 week gestation). The femur length, cross-sectional areas, volume, splaying indices and angles were automatically measured using the RF method. The relationship between these measurements and the fetal gestational age and maternal vitamin D was investigated. Segmentation of a fetal femur is fast (2.3s/volume), thanks to the parallel implementation. The femur volume, length, splaying index were found to significantly correlate with fetal gestational age. Furthermore, significant correlations between the automatic measurements and 10 nmol increment in maternal 25OHD during second trimester were found.
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Fetal skeletal imaging using 3D ultrasound and the impact of maternal vitamin DIoannou, Christos January 2012 (has links)
Background: Previous research suggests that vitamin D deficiency during pregnancy may be associated with suboptimal fetal growth, but direct evidence is lacking. Our objectives were 1) to develop a method for measurement of the fetal sphenoidal fontanelle area (FA) and femur volume (FV) using 3D ultrasound; 2) to create normal charts for FA and FV; and 3) to correlate FA and FV with maternal vitamin D concentration. Methods: FA measurement in 3D was evaluated in vitro and in vivo. Different segmentation methods for FV measurement were explored. A novel FV method was described which consists of three linear measurements and a volume equation; this was validated in vitro and also by comparing FV measured sonographically to the true volume assessed by computed tomography (CT), in 6 cases following pregnancy termination. A cohort of 868 uncomplicated pregnancies was selected on the basis of strict inclusion criteria; participants underwent serial ultrasound scans for FV and multilevel modeling was used for the creation of a “prescriptive” FV chart. Finally, a different cohort of 357 healthy pregnant women had serum vitamin D levels and FV ultrasound at 34 weeks gestation and dual emission x-ray absorptiometry (DEXA) of their neonates in order to investigate the prenatal determinants of fetal bone mass. Results: FA measurement was accurate in vitro, but unreliable in vivo and was therefore abandoned. A novel FV method had excellent agreement with CT and superior repeatability compared with segmentation-based methods. A normal FV chart was created and the regression equations for the median and percentile values were presented. Vitamin D demonstrated a significant correlation with FV. Conclusions: FV is a reliable sonographic marker of skeletal growth. Maternal vitamin D deficiency is associated with reduced FV. This finding has public health implications as reduced bone mass may increase the lifetime risk of osteoporosis, through fetal programming.
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Correlación entre el estado nutricional materno y la ganancia de peso gestacional con macrosomía fetal en el hospital Uldarico Rocca 2014Espinoza Venero, Amadeo Ivanovich, Romero Miranda, Gina Senndy 12 January 2015 (has links)
Birth weight influences the future life of the newborn. The fetal malnutrition (excess or deficit) can influence the development of chronic diseases during their lifetime as has been evidenced in several studies.
Maternal nutritional status and gestational weight gain may influence the weight of newborn leading some alterations as macrosomía and negative consequences for adult life.
The present study aims to establish the correlation between maternal nutritional status and gestational weight gain with fetal macrosomia in Uldarico Rocca hospital from Villa El Salvador 2014.
Material and Methods: The study is retrospective, transversal, descriptive and applied. The design is observational. Data from obstetric medical records of the mothers was collected. Pearson bivariate correlation test and bivariate logistic regression analysis was used.
Results: 190 postpartum women and their newborns were included in the study. 50% of newborns (n=95) had birth weight equal o > 4kg. (macrosomic) 54% of mothers (n= 102) were overweight or obese in early pregnancy while 57% (n= 108) earn above gestational weight recommended by pre gestational nutritional status. Significant positive correlation between gestational weight gain and birth weight (p <0.05) was observed.
Conclusions: There is significant positive correlation between gestational weight gain and birth weight. No significant positive correlation was found between pre gestational BMI and birth weight.
Review and / or preparation of nutritional care protocols to pregnant women are recommended, ensuring their access to personalized and specialized care by trained professionals and trained for this purpose. / El peso al nacer tiene influencia en la vida futura del recién nacido. La malnutrición fetal (por exceso o por déficit) puede condicionar el desarrollo de enfermedades crónicas durante el transcurso de su vida como también se ha podido evidenciar en diversos estudios.
El estado nutricional materno y la ganancia de peso gestacional pueden influir en el peso del recién nacido dando lugar a algunas alteraciones como macrosomía y las consecuencias negativas para la vida adulta.
El presente estudio tiene como objetivo establecer la correlación entre el estado nutricional materno y la ganancia de peso gestacional con macrosomía fetal en el Hospital Uldarico Rocca de Villa El Salvador 2014.
Material y métodos: El estudio es de tipo aplicado, retrospectivo, transversal y descriptivo. El diseño es observacional. Se recogió los datos de las historias clínicas obstétricas de las madres. Se utilizó test de correlación bivariada de Pearson y análisis de regresión logística bivariada.
Resultados: Se estudió a 190 puérperas y sus recién nacidos. Los resultados mostraron que el 50% de los recién nacidos (n=95) tuvieron peso al nacer igual o > 4kg (macrosómicos). El 54% las madres (n= 102) presentaron sobrepeso u obesidad al inicio del embarazo mientras que el 57% (n= 108) ganó peso gestacional por encima de lo recomendado según su estado nutricional pre gestacional. Se halló correlación positiva y significativa entre la ganancia de peso gestacional y peso al nacer (p< 0.05).
Conclusiones: Existe correlación positiva y significativa entre la ganancia de peso gestacional y peso al nacer. Se encontró correlación positiva no significativa entre el IMC pre gestacional y peso al nacer.
Se recomienda la revisión y/o elaboración de los protocolos de atención nutricional a la gestante, asegurando su acceso a la atención personalizada y especializada por parte de profesionales capacitados y entrenados para tal fin.
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Fetální mikrochimérismus u gynekologických malignit. / Fetal microchimerism in gynecologic malignancies.Pírková, Petra January 2012 (has links)
The existence of fetal microchimerism has been demonstrated many years ago. This phenomenon is associated with observation of two or more genetically different populations of cells present in one person. Fetal microchimerism originates naturally during pregnancy, by bidirectional transfer of the cells through placenta from fetus to mother (fetal microchimerism) and from mother to fetus (maternal microchimerism). In some cases fetal cells persisted in mother for decades after pregnancy. In my thesis I showed the presence of fetal microchimerism in tissues of endometrial cancer, breast cancer and ovarian cancer and in control, nonmalignant tissues. I worked with deep-frozen tissues, native tissues and cell cultures created from native tissues. I planed also the analysis of paraffin-embedded tissues; however this type of material showed to be unusable for fetal cells detection. On the contrary, native and deep-frozen tumor and control tissues are suitable for this type of research and fetal microchimerism was observed in part of samples. For detection and amplification of DNA extracted from tissues and cell cultures I used quantitative real-time PCR and SRY gene located on the Y chromosome as a marker of fetal cells. I detected the presence of male fetal cells. Fetal genome was found in both tumor and...
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Influência da deficiência ou suplementação com selênio durante o período gestacional de ratas na suscetibilidade da progênie feminina à carcinogênese mamária / Influence of selenium deficiency or supplementation during rat gestational period on the susceptibility of female offspring to mammary carcinogenesisRosim, Mariana Papaléo 04 March 2016 (has links)
Fatores dietéticos como o selênio (Se) são apontados como importantes moduladores do risco de desenvolvimento do câncer de mama. Essa neoplasia pode apresentar sua origem no início do desenvolvimento e, assim, a alimentação materna poderia ter importantes repercussões na programação fetal da doença. A fim de verificar se diferentes concentração de selênio na dieta materna poderiam programar o risco da progênie feminina ao câncer de mama, ratas foram alimentadas com ração contendo 0,15 (CO), 1,0 (SUP) ou 0,05 (DEF) ppm de Se durante a gestação e sua progênie feminina iniciada com DMBA. A progênie do grupo SUP apresentou menor suscetibilidade à carcinogênese, indicado pelo menor número médio e multiplicidade de adenocarcinomas mamários (p< 0,05), enquanto a do grupo DEF apresentou maior suscetibilidade à carcinogênese, indicado pela maior incidência dos mesmos (p< 0,05). Mães do grupo DEF apresentaram menor concentração de Se no sangue (p< 0,05) e sua prole apresentou menor atividade da enzima GPx1 (p< 0,05). Além disso, observou-se na glândula mamária da progênie de 50 dias menor expressão (western blot e qPCR) de ERα, Her-2, EGFR e Ras no grupo SUP em comparação aos grupos CO e DEF (p< 0,05). Analisou-se, ainda, o padrão de metilação global do DNA (HPLC-DAD), expressão das enzimas DNMT1, 3a e 3b (qPCR), o padrão global de modificações pós traducionais em histonas (western blot) e o padrão de metilação da região promotora do gene Erα (modificação com bissulfito e pirossequenciamento) na glândula mamária da progênie de 50 dias. Não houve diferença no padrão de metilação global do DNA e expressão das enzimas DNMTs (p>0,05). Houve aumento na expressão de H4K16 acetilada nos grupos SUP e DEF (p< 0,05). Finalmente, em comparação a progênie do grupo DEF, a do grupo SUP apresentou região promotora de Erα com aumento marginal (p=0,07) na metilação de dois dinucleotídeos CpG. Conclui-se que o consumo de diferentes concentrações de Se na dieta materna tem impacto sobre a suscetibilidade da progênie ao câncer de mama na vida adulta através da modulação da expressão de receptores e oncogenes relacionados ao desenvolvimeto dessa neoplasia, além da influência em processos epigenéticos. Tais resultados apontam para a existência de uma \"janela de programação\" no início do desenvolvimento sensível a ação do Se, resultando em diminuição do risco de câncer de mama quando suplementado na dieta materna e o inverso quando de sua deficiencia. / Based on epidemiological studies and animal models, the essential micronutrient selenium has been highlighted as a promising dietary factor associated to breast cancer risk reduction. Breast cancer may have its origin in early development and thus the maternal diet could have important implications in the fetal programming of the disease. In order to ascertain whether differences in selenium concentration in maternal diet could modulate the susceptibility of female offspring to breast cancer, a biological assay was conducted in which female rats were fed a diet with 0.15 (CO), 1.0 (SUP) or 0.05 (DEF) ppm of selenium during gestational period and the female offspring subjected to a mammary carcinogenesis model induced by DMBA. SUP group offspring presented decreased susceptibility to mammary carcinogenesis, as indicated by lower (p< 0,05) average number and multiplicity od adenocarcinomas, while the DEF group offspring had a greater susceptibility, as indicated by the increase (p< 0,05) in adenocarcinomas incidency. Mothers of the DEF group pesented lower (p< 0,05) Se blood concetrations and their offspring presented lower (p<0,05).GPx1 activity. In addition, there was a decrease (p< 0,05) in ERα, Her-2, EGFR and Ras expression (western blot and qPCR) in the mammary gland of 7 weeks old female SUP group offspring when compared to CO and DEF groups offspring. DNA global methylation pattern (HPLC-DAD), DNMT1, 3a e 3b expression (qPCR), global pattern of post-translational modification in histones (western blot) and methylation status of Erα promoter region (bisulfite modification and pyrosequencing) were also evaluated in the mammary gland of 7 weeks old offspring. There was no diffrence (p>0,05) in DNA global methylation pattern and DNMTs expression. There was an increase in acetilated H4K16 expression in groups SUP and DEF (p< 0,05). Lastly, when compared to DEF offspring, the SUP offspring presented a marginal increase in the methylation of two CpG dinucleotides in the Erα promoter region. In conclusion, the consumption of different selenium concentration in maternal diet plays a role in the progeny\'s breast cancer susceptibility through the modulation of receptors and oncogenes expression, in addition to modifications in epigenetic patterns. These results indicate the presence of a \"programming window\" in the beggining of development susceptible to selenium effects, resulting in decreased breast cancer risk when supplemented and the opposite when deficient.
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Efeito do manejo nutricional sobre a maturação do eixo reprodutivo somatotrófico no início da puberdade de novilhas Nelore / Effect of nutrient management on the maturation of the reproductive axis in somatotrophic onset of puberty in heifers NelloreNepomuceno, Delci de Deus 10 December 2012 (has links)
Objetivou-se no presente estudo, avaliar o efeito da nutrição proteica no terço final da gestação de vacas Nelore, seguido de estratégias de suplementação e/ou alimentação de suas crias fêmeas sobre a idade à puberdade até os 18 meses. O delineamento utilizado foi o inteiramente casualizado em esquema fatorial 2x2x2; constituindo-se de: 2 manejos suplementar das vacas no pré-parto (Fase I); 2 manejos suplementar das crias (Fase II) e 2 manejos alimentar na recria (Fase IIIA). Na Fase I, 241 vacas foram suplementadas com farelos de soja na proporção de 0,5kg/vaca/dia (Tratamento 1) e 258 vacas foram mantidas sem acesso a suplementação Tratamento 2 (controle - Fase I). Cerca de metade do número de vacas e suas crias fêmeas, nascidas na Fase I, foram distribuídas em dois tratamentos na Fase II-(suplementação das crias) aos 110 dias de idade das crias, as quais passaram receber ou não uma mistura mineral proteica energética em creep-feeding, constituindo assim, os tratamentos suplementação de bezerras em creep-feeding (n =119) e controle (sem suplementação, n =122 ) na Fase II até os 205 dias de idade (desmama). Na fase III A, metade das bezerras de cada grupo na fase II foram manejados em confinamentos (n=119) e a outra metade permaneceu no pasto (Grupo controle, n = 122), até os 320 dias de idade. Na fase IIIB, todas as novilhas foram manejados juntos a pasto e submetidas a estação de monta a partir dos 440 dias aos 560 dias de idade. Os sistemas de suplementação das vacas e bezerras na fase de cria não afetaram o peso corporal, concentração de IGF-1 e percentual de peso adulto das novilhas no início da estação de monta (P > 0,05). O manejo das novilhas em confinamento na fase IIIA, aumentou o número de novilhas púberes (31,9% vs 13,9%; P < 0,01), para as novilhas alimentadas ou não em confinamento, respectivamente. Entretanto, a alimentação em confinamento não ocasionou diferença na idade que estas atingiram a puberdade. Considerando apenas as novilhas que atingiram à puberdade (n = 55) houve efeito de interação entre as fases de suplementação/alimentação e a idade à puberdade (P < 0,05). Para as vacas manejadas na Fase I, a suplementação influenciou a ciclicidade das mesmas no momento da IATF (68,9% vs 55,4%; P < 0,05), porém não ocasionou diferença no número de vacas prenhes (60,1 vs 55,3%; P > 0,05), vacas suplementadas e não suplementadas, respectivamente. Similarmente, a suplementação das novilhas em creep-feeding, não influenciou a taxa de prenhez das vacas (P > 0,05). Em conclusão, a suplementação das vacas com fontes proteicas não influenciou a idade a puberdade de novilhas até os 18 meses, sendo que o manejo alimentar em confinamento aumentou o número de novilhas púberes em relação com as manejadas no pasto. / The aim of the present study was to evaluate the effect of protein nutrition in the final third of gestation of Nelore cows, followed by supplementation strategies and / or feed their young females over the age of puberty until 18 months. The experimental design was a completely randomized factorial 2x2x2; constituting of: 2 suplementary managements of cows in pre-partum (Phase I); 2 supplementary managements of offspring (Phase II) and 2 alimentary managements during rearing (Phase IIIA). In Phase I, 241 cows were supplemented with soybean meal at the rate of 0.5 kg / cow / day (Treatment 1) and 258 cows were kept without access to supplemental Treatment 2 (control - phase I). About half of the cows and their female offspring, born in Phase I, were assigned to two treatments in Phase-II (supplementation of cubs) at 110 days of age of the offsprings, which now receive or not a mineral mix protein energy in creep-feeding, constituting, treatments supplementation in calves creep-feeding (n = 119) and control group (without supplementation, n = 122) in Phase II until 205 days of age (weaning). In phase III A, half of each group of calves in phase II were managed in feedlots (n = 119) and the other half remained in the pasture (control group, n = 122), up to 320 days of age. In stage IIIB, all heifers were managed together and submitted to the pasture breeding season from 440 days to 560 days old. Supplementation systems of cows and calves during the growing period did not affect body weight, concentration of IGF-1 and percentage of mature weight of heifers at the beginning of the breeding season (P> 0.05). The management of heifers in the feedlot phase IIIA, increased the number of pubertal heifers (31.9% vs 13.9%, P <0.01) for heifers fed in confinement or not, respectively. However, feeding in confinement caused no difference in age they reached puberty. Considering only heifers reached puberty (n = 55) there was an interaction effect between phases of supplementation / nutrition and age at puberty (P <0.05). For cows managed in Phase I, supplementation influenced the cyclicality of the same at the time of TAI (68.9% vs 55.4%, P <0.05), but caused no difference in the number of pregnant cows (60.1 vs 55.3%, P> 0.05), supplemented and nonsupplemented cows, respectively. Similarly, the addition of heifers in creep-feeding did not influence the rate of pregnancy in cows (P> 0.05). In conclusion, supplementation of cows with protein sources did not influence the age at puberty in heifers up to 18 months, and feeding management in confinement increased the number of pubertal compared with those managed on pasture.
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