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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Oxidative and nitrative stress biomarkers in amniotic fluid and their association with fetal growth and pregnancy outcomes

El-Halabi, Dima. January 2007 (has links)
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.
32

Early second trimester amniotic fluid erythropoietin and pregnancy outcomes

Di Giovanni, Jessica Louise. January 2008 (has links)
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.
33

Characterization and Therapeutic Potential of Human Amniotic Fluid Cells in Mediating Neuroprotection

Jezierski, Anna 19 September 2013 (has links)
Brain injury, either surgically induced or as a result of trauma or stroke, is one of the leading causes of death and disability worldwide. Since transplantable stem cell sources are showing a great deal of promise and are actively being pursued to provide neuroprotection post-injury, in this body of work, we set out to characterize and examine the therapeutic potential of amniotic fluid derived (AF) cells as a potential cell source for cell-based therapies in mediating neuroprotection post-injury. Despite their heterogeneity, we found that AF cells are mainly epithelial in origin and express various genes involved in stem cell maintenance and neural commitment. A very small subset of AF cells also express pluripotency markers OCT4a, SOX2 and NANOG, which can be enriched for by single cell cloning. SOX2 positive clones have the capacity to give rise to a neuronal phenotype, in neural induction conditions, which can be used to examine the neural differentiation capabilities of AF cells. Subsequently, we examined the ability of AF cells to mediate a neuroprotective effect in a surgically induced brain injury model through gap junctional-mediated direct cell-cell communication and as a vehicle for GDNF delivery post-injury. AF cells express high levels of CX43 and are able to establish functional gap junctional intercellular communication (GJIC) with cortical astrocytes. We report an induction of Cx43 expression in astrocytes following injury and demonstrate, for the first time, CX43 expression at the interface between implanted AF cells and host astrocytes. In an effort to boost host endogenous neuroprotective mechanisms post-injury, via neurotrophic factor delivery, we engineered AF cells to secrete GDNF (AF-GDNF). GDNF pre-treatment significantly increased AF cell and cortical neuron survival rates following exposure to hydrogen peroxide. AF-GDNF cells, seeded on polyglycolic acid (PGA) scaffolds, survived longer in serum-free conditions and continued to secrete GDNF post-implantation activating the MAPK/ERK signaling pathway in host neural cells in the peri-lesion area. Despite some promising trends, we did not observe significant behavioural improvements following AF-GDNF/PGA implantation nor reduced lesion volume during the 7 day time-frame. In conclusion, through GJIC with cortical astrocytes and delivery of exogenous neurotrophic factors, AF cells hold great promise in mediating neuroprotection post-injury.
34

Peptide pattern of amniotic fluid and its correlation with protein composition of fetal membranes: the search for new potential biomarkers to predict preterm premature rupture of membranes / Vaisiaus vandenų peptidų ir dangalų baltymų sudėties koreliacija: naujų potencialių neišnešioto vaisiaus priešlaikinio dangalų plyšimo grėsmės biožymenų paieška

Machtejevienė, Eglė 19 September 2013 (has links)
The aim of the research was to find new potential biomarkers of preterm premature rupture of membranes. The amniotic fluid and fetal membranes peptidic composition was analyzed using a fully automated 2D liquid chromatographic system coupled to mass spectrometry. A comparison of peptidomes of amniotic fluid and amniochorionic membranes with preterm premature rupture and term intact membranes was performed. Ten proteins from amniotic fluid were identified as potential biomarkers for PPROM. The created map of amniotic fluid peptides and proteins depending on the gestational age is important for proteomics-based identification of biomarkers for fetal abnormalities and other pregnancy complications. / Mokslinio darbo metu siekta nustatyti potencialius priešlaikinio neišnešioto vaisiaus dangalų plyšimo biožymenis. Panaudojant dvidimensinę skysčių chromatografiją bei masių spektrometriją išanalizuota vaisiaus vandenų ir dangalų peptidinė sudėtis. Ištirti ir palyginti amniochorioninės membranos ir vaisiaus vandenų peptidai bei su jais siejami baltymai, kai prieš laiką plyšta neišnešioto vaisiaus dangalai arba vaisius išnešiojamas iki numatyto gimdymo termino ir dangalai išlieka sveiki. Išanalizavus skirtumus, nustatyti nauji galimi priešlaikinio neišnešioto vaisiaus dangalų plyšimo biožymenys.
35

Amniotic fluid fatty acids and cholesterol and their association with pregnancy outcomes

Enros, Erin. January 2006 (has links)
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.
36

Σχέση σιδήρου και φερετίνης ορού μητέρας και νεογνού

Μαρκαντές, Κ. 19 May 2010 (has links)
- / -
37

Quantificação de citocinas no líquido amniótico de bezerros nelore oriundos de produção in vitro, tranferência de embrião e inseminação artificial colhido no momento do parto

Araujo, Carla Fredrichsen Moya [UNESP] 27 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-27Bitstream added on 2014-06-13T20:19:19Z : No. of bitstreams: 1 moya_cf_dr_botfmvz.pdf: 348880 bytes, checksum: dfb1789c8b1c607bbc3d25ebe0e02063 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tendo em vista, a incidência de problemas fetais observados no momento do parto de animais produzidos in vitro (PIV) e a escassez de literatura nesta área, o presente estudo teve por objetivo determinar os níveis de fator de necrose tumoral-alfa (TNF-), interferon-gama (IFN-), interleucina-6 (IL-6) e IL-8 no fluido amniótico de bezerros oriundos de PIV comparando com aqueles obtidos pela transferência de embrião convencional e inseminação artificial no momento do parto, na tentativa de auxiliar na resolução de problemas ainda pouco conhecidos que são observados a campo durante emprego comercial da PIV. Foram utilizados sessenta animais divididos em grupo 01: vinte vacas gestando bezerros da raça Nelore PO de inovulações de embriões oriundos de doadoras superovuladas pelo método convencional (TE); grupo 02: vinte vacas gestando bezerros Nelore PO de inovulações de embriões oriundos de PIV; grupo 03: vinte vacas Nelore PO gestando bezerros oriundos de inseminação artificial (IA) - controle. Todos os partos dos animais do experimento foram observados. Durante a fase de expulsão e após a ruptura do alantocórion, foi realizada a punção do âmnion para a colheita de 15mL de líquido amniótico utilizando-se agulhas e seringas descartáveis compatíveis. O material foi depositado em tubo plástico e congelado em freezer para posterior análise laboratorial. O acompanhamento do padrão de desenvolvimento dos bezerros no periparto foi realizado. Após a descongelação das amostras foi realizado ensaio imunoenzimático (ELISA) para a dosagem de TNF-, com emprego do Kit comercial: ESS0011 - Bovine TNF Alpha, para IFN- foi Kit comercial: ESS0026 - Bovine IFN-, para IL-6 foi Kit comercial: ESS0029 - Bovine IL-6 da Pierce Biotechnology e para IL-8 Kit... / In view, the incidence of fetal problems seen at the time of birth of animals in vitro production and the be short of the literature in this area, this study aimed to determine the levels of tumor necrosis factor (TNF-), interferon-gamma (IFN-), interleukin-6 (IL-6) and IL-8 in amniotic fluid of calves from in vitro production (IVP) compared with those obtained by conventional embryo transfer and artificial insemination at the delivery, in an attempt to assist in solving problems that are still little known observed in simulations and the experimental field of commercial employment during IVP. Sixty animals used were divided into groups: 1 - Twenty Nelore cross-breed cows pregnant with Nelore calves of embryos transfer conventional method (ET); 2 - Twenty Nelore cross-breed cows pregnant with Nelore calves obtained by in vitro production after follicular aspiration; 3 - Twenty pregnant Nelore cows bearing calves obtained by artificial insemination (AI). All births of the animals of the experiment were observed. During the expulsion phase the amnion was punctured and 15mL of fluid were collected using a needle and syringes compatible. The material was deposited on plastic tube and frozen in freezer for later analysis. Monitoring the pattern of development of the calves in peripartum was performed. The cytokines levels were measured by immunoenzymatic assay (ELISA). The commercial kit used was: ESS0011 - Bovine TNF Alpha, ESS0026 - Bovine IFN- gamma, ESS0029 - Bovine IL-6 Pierce Biotechnology and comercial Kit: D8000C - Human IL-8 of the R & D Systems. The protocol was performed according to the manufacturer´s recommendations. The densities were evaluated in automatic optical reader ELISA. The well plates were read at 450nm. The Kruskal-Wallis Test was used for statistical analysis... (Complete abstract click electronic access below)
38

Tipificação citológica do líquido amniótico no momento do parto de bezerros Nelore oriundos de produção In Vitro, transferência de embrião e inseminação artificial /

Moya, Carla Fredrichsen. January 2005 (has links)
Orientador: Nereu Carlos Prestes / Resumo: A proposta do presente estudo foi descrever as diferenças no padrão morfológico das células do fluido amniótico, no momento do parto. Comparando os resultados obtidos de bezerros nelores oriundos de produção in vitro, transferência de embriões e inseminação artificial. Utilizaram-se 60 animais, divididos em Grupo 01: vinte vacas inovuladas com embriões Nelore produzidos in vitro (PIV) a partir de colheita de oócitos por aspiração folicular de doadoras, Grupo 02: vinte vacas gestando bezerros nelores originados de inovulações de embriões oriundos de doadoras superovuladas pelo método convencional, e Grupo 03: vinte vacas nelores PO gestando bezerros oriundos de inseminação artificial (controle). Próximo ao parto as vacas foram transferidas para piquete maternidade com acompanhamento dos partos. Durante a fase de expulsão e após a ruptura do alantocórion realizou-se a punção do âmnion para colheita de 20mL de liquido, que foi depositado em tubo plástico e congelado em freezer. Para a classificação celular as amostras, pós-descongelação, foram centrifugadas na Citocentrifuga (Revan Centrifuga Ciclo Cito) a 4000rpm durante seis minutos e empregou-se a técnica de coloração Hematoxilina-Shorr. Ao final deste procedimento, as lâminas citológicas foram montadas com lamínulas empregando Bálsamo do Canadá e posteriormente (após o período de secagem) observadas em microscópio óptico com aumentos de 200x e 400x para visualização das características morfológicas e tintoriais das células epiteliais do feto. Para avaliação da maturidade epidérmica utilizou-se a técnica de coloração de Sulfato Azul do Nilo bem como a porcentagem de células queratinizadas (coloração Hematoxilina-Shorr). As células basais e parabasais não foram encontradas nas lâminas citológicas das amostras de líquido amniótico analisadas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of the present study was to describe the differences in the cytological pattern of the amniotic fluid, at the moment of delivery, comparing the data from Nelore calves obtained by in vitro production, embryo transfer and artificial insemination. Sixty (n=60) Nelore cows were divided in group 01: Twenty cows (n=20) pregnant with Nelore calves obtained by in vitro production (IVP) after follicular aspiration; group 02: Twenty cows (n=20) pregnant with Nelore calves obtained by superovulation of embryo donors (ET); group 03: Twenty Nelore cows (n=20) pregnant of calves obtained by artificial insemination (AI; control). Near to the labor, the cows were transferred to a maternal paddock, permitting delivery observation. During the expulsion phase, after the rupture of the alantochorion the amnion was punctured and 20ml of fluid were collected in a plastic device and frozen. The samples, after being thawed, were centrifuged at 4000 rpm, during 06 minutes the Hematoxilin-Shorr stain was applied, after this, the glass slides were covered with Canadian balsame and analyzed in optical microscopy. To the evaluation of the epidermal maturity were used the Blue Nile Sulfate stain, as well the percent of keratinizaded cells observed in the Hematoxilin-Shorr stain. The basal and parabasal cells were not found on the slides of the amniotic fluid samples analyzed. The small intermediate cells (CIP) had its shape as an oval or polygonal form with large cytoplasm and central nucleus. The large intermediate cell (CIG) showed a central nucleus and a bigger nucleus-cytoplasm relation compared to the superficial cells. These were the largest cells found. They showed keratinization with angular edges, having both a picnotic nucleus (CSN) and no nucleus at all. (CSA). The technique of Blue Nile Sulfate stain did not showed satisfactory for the evaluation of the fetal maturity, in spite of some records... (Complete abstract click electronic access below) / Mestre
39

Ceratoplastia lamelar em cães usando membrana amniótica eqüina. Estudo clínico e morfológico / Lamelar keratoplasty of dogs using equine amniotic membrane. Clinical and morphological study

Andréa Barbosa de Azevedo 22 June 2006 (has links)
A membrana amniótica tem se consolidado no tratamento das afecções da superfície ocular. Assim, o objetivo deste estudo foi avaliar a viabilidade e a eficácia do implante de MA eqüina, preservada em glicerina a 98%, na reparação de ceratoplastias lamelares em cães, por meio do estudo da avaliação clínica pós-operatória dos animais, do tempo de cicatrização, da reconstrução da arquitetura da córnea, da resposta inflamatória, e da composição colágena do estroma corneal no local do implante. Foram selecionados 12 cães, sem raça definida, machos ou fêmeas, divididos em quatro grupos de três, que tiveram tempos de observação distintos: 2, 7, 21 e 40 dias. Foi realizada ceratoplastia lamelar de 5 mm de diâmetro em um dos olhos de cada animal, seguida da aplicação do implante de membrana amniótica eqüina de 6 mm. Durante o período de observação, exame clínico oftalmológico foi realizado nos cães, com intervalos de 48 horas e ao final deste período, foram submetidos á eutanásia. Os olhos em estudo foram enucleados e fixados para posterior análise. Foram utilizados três métodos de coloração para o estudo histológico do tecido implantado: hematoxilina-eosina (HE), ácido periódico de Schiff (PAS) e picrossirius. Além disso, procedeu-se a imunomarcação para colágenos tipo I, III, e V, com uso de pepsina para digestão das fibras colágenas heterotípicas exposição dos epítopos. Clinicamente os implantes foram completamente epitelizados em aproximadamente 10 dias, os neovasos apresentaram involução progressiva a partir dos 20 dias de pós-operatório, estando ausentes ao final dos 40 dias de observação, restando apenas uma nébula no local da lesão. À microscopia óptica, observou-se resposta inflamatória moderada, presença de epitélio pavimentoso estratificado aos sete dias e epitelização completa aos 21 dias. Aos 40 dias a membrana basal do epitélio apresentou-se reconstituída. O colágeno tipo I teve sua expressão no estroma intensificada aos 21 dias de pós- operatório. O colágeno tipo III está presente na membrana amniótica, sua a ausência no local do implante, aos 21 dias, mostrou remodelamento do tecido implantado. O colágeno tipo V, presente no estroma da córnea, teve sua expressão aumentada aos 7 e 21 dias, retornando à distribuição normal aos 40 dias de pós-operatório. Assim concluí-se que: a membrana amniótica eqüina é viável como implante em córnea de cão, sendo incorporada ao estroma, resultando em restabelecimento parcial da transparência no local de implante; o colágeno do tecido implantado é remodelado e substituído já aos 21 dias de pós-operatório; a pepsina foi eficiente na digestão das fibras e exposição dos epítopos dos colágenos nas fibras heterotípicas / The amniotic membrane has consecrated itself in the treatment of ocular surface diseases. The objective of this study was to evaluate the efficiency and viability of the equine amniotic membrane graft, preserved in glycerin at 98%, in the lamellar keroplasty recovery in dogs. Evaluation was based on clinical post-surgical exam, healing time, corneal architectural reconstruction, inflammatory response and collagen composition of the corneal stroma at the graft site. Twelve mixed-breed, male and female dogs were divided into four groups of three dogs. Each group was submitted to different observation periods of 2, 7, 21 and 40 days. Each dog was submitted to a 5 mm lamellar keratoplasty in one eye, followed by a 6 mm equine amniotic membrane graft. Each animal was submitted to clinical ophthalmologic exam every 48 hours. At the end of the evaluation period, the animal was euthanized and the grafted eye was removed and fixated for posterior analysis. For the histological study of the tissue graft, three methods of coloration were used: hematoxylin eosin (HE), periodic acid of Schiff (PAS) and picrosirius. Immunolocalization for the collagen types I, III and V using pepsin for fiber digestion of heterotypic fibrils and epitope exposure, was made. Clinically, the grafts were completely epithelized in approximately 10 days and neovascularization regressed progressively 20 days after surgery, being completely absent after 40 days, when only a nebula remained at the graft site. Optic microscopy revealed mild inflammatory response and presence of stratified pavement epithelium after 7 days and complete epithelization 21 days after surgery. At the end of 40 days the basal membrane was reconstituted. Type I collagen had its expression in the stroma intensified 21 days after the surgery. By day 21 the absence of collagen III in the corneal stroma showed graft remodeling, since this was formerly present in the amniotic membrane. The expression of type V fiber in the corneal stroma showed a mildly intensified expression at 7 and 21 days of observation, but returned to its normal distribution 40 days after surgery. Conclusion was that the equine amniotic membrane is a viable graft for the dog\'s cornea as it is incorporated to the stroma, resulting in partial transparency at the site of the graft. Twenty-one days after surgery, collagen from the graft is already remodeled and substituted. Pepsin is efficient for fiber digestion and collagen epitope exposure in heterotypical fibers.
40

Characterization and Therapeutic Potential of Human Amniotic Fluid Cells in Mediating Neuroprotection

Jezierski, Anna January 2013 (has links)
Brain injury, either surgically induced or as a result of trauma or stroke, is one of the leading causes of death and disability worldwide. Since transplantable stem cell sources are showing a great deal of promise and are actively being pursued to provide neuroprotection post-injury, in this body of work, we set out to characterize and examine the therapeutic potential of amniotic fluid derived (AF) cells as a potential cell source for cell-based therapies in mediating neuroprotection post-injury. Despite their heterogeneity, we found that AF cells are mainly epithelial in origin and express various genes involved in stem cell maintenance and neural commitment. A very small subset of AF cells also express pluripotency markers OCT4a, SOX2 and NANOG, which can be enriched for by single cell cloning. SOX2 positive clones have the capacity to give rise to a neuronal phenotype, in neural induction conditions, which can be used to examine the neural differentiation capabilities of AF cells. Subsequently, we examined the ability of AF cells to mediate a neuroprotective effect in a surgically induced brain injury model through gap junctional-mediated direct cell-cell communication and as a vehicle for GDNF delivery post-injury. AF cells express high levels of CX43 and are able to establish functional gap junctional intercellular communication (GJIC) with cortical astrocytes. We report an induction of Cx43 expression in astrocytes following injury and demonstrate, for the first time, CX43 expression at the interface between implanted AF cells and host astrocytes. In an effort to boost host endogenous neuroprotective mechanisms post-injury, via neurotrophic factor delivery, we engineered AF cells to secrete GDNF (AF-GDNF). GDNF pre-treatment significantly increased AF cell and cortical neuron survival rates following exposure to hydrogen peroxide. AF-GDNF cells, seeded on polyglycolic acid (PGA) scaffolds, survived longer in serum-free conditions and continued to secrete GDNF post-implantation activating the MAPK/ERK signaling pathway in host neural cells in the peri-lesion area. Despite some promising trends, we did not observe significant behavioural improvements following AF-GDNF/PGA implantation nor reduced lesion volume during the 7 day time-frame. In conclusion, through GJIC with cortical astrocytes and delivery of exogenous neurotrophic factors, AF cells hold great promise in mediating neuroprotection post-injury.

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