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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.
11

In Vitro Study of Recruitment Ability of Macrophages and Trophoblasts in Early Human Pregnancy

Wendel, Caroline January 2010 (has links)
The tolerance towards the semi-allogenic foetus is obtained through both systemic and local changes in the maternal immune response. Locally, in the decidua, the cell composition differs from that found in the blood; natural killer (NK) cells and macrophages being the major cell types. Decidual macrophages (dMØ), which are alternatively activated, and trophoblasts, placental cells of foetal origin, are believed to participate in the foetal tolerance at the foetal-maternal interface. To test the recruitment ability of macrophages and trophoblasts, and to test if these cells are responsible for the special cell composition in the decidua, a migration assay was established. In this migration assay peripheral blood mononuclear cells (PBMC) were allowed to migrate through Matrigel-coated transwell inserts into lower wells containing a recruiting stimulus. After testing several conditions, a protocol was established for further use. The results showed that in vitro alternatively activated macrophages, which display many of the surface markers as dMØ, hold a recruiting ability and recruit monocytes. Further there was an indication that trophoblasts also hold a recruiting ability. Neither cell types were shown to recruit NK cells. In conclusion, this study presents a suitable protocol for assessing chemotactic factors and different cell type’s ability to recruit cells from blood. Although the experiments need to be repeated and extended and the recruitment ability of dMØ needs to be evaluated in detail before a final conclusion can be drawn, the preliminary data indicated that macrophages and trophoblasts can recruit monocytes.
12

Estudo ultraestrutural e imunohistoquímico do estroma uterino durante a gestação de camundongos deficientes em decorim. / Ultrastructural and immunohistochemical studies of the uterine stroma in the decorin-deficient mice during pregnancy.

Juliane Cristina Trevisan Sanches 27 March 2009 (has links)
No presente estudo realizamos uma análise ultraestrutural e imuhistoquímica da organização das fibrilas de colágeno no endométrio durante a gestação de camundongos silvestres e deficientes em decorim. Os resultados mostraram que as fibrilas de colágeno em ambos os genótipos sofrem grande variação de forma e tamanho. Observou-se variação significante, na percentagem de distribuição dos diâmetros das fibrilas de colágeno existentes na região decidualizada em ambos os genótipos, porém foi maior nos animais Dcn-/-. Estes animais também apresentam maior percentagem de fibrilas finas quando comparados aos animais Dcn+/+. Observamos ainda que biglicam é expresso no endométrio não decidualizado dos animais Dcn-/-, no 3º dia de gestação. A expressão de lumicam mostrou-se nítida no estroma decidualizado e não decidualizado nos animais Dcn-/- no 7º dia de gestação e foi ausente nos animais Dcn-/-. Estes resultados mostraram que a ausência do decorim promove distúrbios no processo de agregação lateral das fibrilas espessas de colágeno. / The present study is an ultrastructural investigation into the organization of collagen fibrils in the pregnant endometrium of wild-type and decorin-deficient mice. Our results showed that collagen fibrils from both genotypes present a great variability of shape and size in cross section. Significant variation in the diameter of collagen fibrils exists in the decidualized endometrium from both groups of animals. In the decidualized endometrium, the diameter of collagen fibrils increases in both genotypes were higher in Dcn-/- than in Dcn+/+ animals. In the Dcn-/- animals the percentage of thin fibrils with diameter is also higher, when compared with Dcn+/+ animals. We also showed that Bgn is expressed in the non decidualized endometrium in the Dcn-/- animals, on day 3 of pregnancy. The expression of lumican showed a very sharp labeling in the decidualized stroma from day 7, and in the non decidualized estroma from Dcn-/- animals. These results suggest that the deficience of decorin may play a role on collagen fibrillogenesis in different stages of pregnancy.
13

Asociación de las características oclusales con la edad y género en niños con dentición decidua de una institución educativa pública del distrito de Ate Vitarte en el año 2013

Flores Bazán, Andrea Alejandra 07 April 2014 (has links)
Objective: To determine the association of features occlusal with age and gender in children with deciduous dentition of a public educational institution in the district of Ate Vitarte in 2013. Methods: The sample was conformed by 108 children with complete deciduous dentition between 3 and 5 years of the IE Amauta No. 1285-216 located in Ate Vitarte in 2013. All variables were recorded on the data collection form, these were, type of arch, primate spaces, palatine hall relation of molars, bilateral terminal molar relation, bilateral canine relationship, curve of Spee, midline, overjet and overbite. In addition to the age and gender of the scholar. Frequencies were obtained and the chi square test were conducted to determine associations between variables. Results:. Only found statistically significant association between superior primates spaces (p=0.041) and inferior (0.002), bilateral terminal molar relation (p=0.040), lower midline (p=0.032) and age. Conclusions: In this study, was found that most of the children presented normal occlusal characteristics. No association of most occlusal characteristics were found with age and gender. / Objetivo: Determinar la asociación de las características oclusales con la edad y género en niños con dentición decidua de una Institución Educativa Pública del distrito de Ate Vitarte en el año 2013. Métodos: La muestra estuvo conformada por 108 niños con dentición decidua completa entre 3 y 5 años de la IE Amauta Nº 1285-216 ubicado en Ate Vitarte en el 2013. Todas las variables fueron registradas en la ficha de recolección de datos, estas fueron el tipo de arco, los espacios primates, relación vestíbulo palatina de molares, plano terminal bilateral, relación canina bilateral, curva de Spee, línea media, overjet y overbite. Además de la edad y género del escolar. Se obtuvo las frecuencias y se realizó la prueba de chi cuadrado para determinar asociaciones entre las variables. Resultados: Se encontró asociación estadísticamente significativa entre los espacios primates superior (p=0.041) e inferior (p=0.002), plano terminal bilateral (p=0.040) y la línea media inferior con la edad (p=0.032). Conclusiones: Se encontró asociación de los espacios primates superior e inferior, plano terminal bilateral y la línea media inferior con la edad. Palabras Claves: Dentición decidua, relación oclusal, plano terminal, espacios primates / Tesis
14

Modifikace barvy dřeva nanočásticemi železa

Kmoníčková, Petra January 2018 (has links)
This thesis clarifies the influence of the content of polyphenolic substances on the color change of oak and larch wood after the modification of surface by iron. The samples were modified by solution of iron nanoparticles at two different concentrations. After that the change of color components was determined. The analysis of polyphenols by Folin-Ciocalteu by spectrophotometric method was made for each sample and also dry matter in the extracts was determined. The final data were subjected to statistical analysis and correlation and regression analysis were performed. Statistically significant correlations for both species were found.
15

Adenosine Levels in the Postimplantation Mouse Uterus: Quantitation by Hplc‐fluorometric Detection and Spatiotemporal Regulation by 5′‐nucleotidase and Adenosine Deaminase

Blackburn, Michael R., Gao, Xiang, Airhart, Mark J., Skalko, Richard G., Thompson, Linda F., Knudsen, Thomas B. 01 January 1992 (has links)
Extracellular adenosine has the potential to influence many aspects of target cell metabolism. The present study has determined the endogenous levels of adenosine in the pregnant mouse uterus and developing embryodecidual unit with respect to the expression of two key enzymes of adenosine metabolism, 5′‐nucleotidase (5′‐NT; EC 3.1.3.5) and adenosine deaminase (ADA; EC 3.5.4.4). To measure adenosine levels, nucleoside extracts were etheno‐derivatized and quantitated by high‐performance liquid chromatography‐fluorescence detection (0.03 pmol/mg protein sensitivity). Adenosine levels were determined to be 0.18 nmol/mg protein in the nonpregnant uterus; however, two statistically significant changes were identified in the pregnant uterus: (1) a periimplantation surge between day 3 (0.24 nmol/mg protein) and day 5 (0.59 nmol/mg protein) of gestation (plug day 0; implantation day 4); and (2) an early postimplantation decline between day 6 (0.54 nmol/mg protein) and day 7 (0.10 nmol/mg protein). The periimplantation adenosine surge coincided with uterine expression of 5′‐NT, an enzyme which catalyzes the irreversible dephos‐phorylation of 5′‐AMP to adenosine. 5′‐NT expression was shown by Northern blot analysis to peak in the embryo‐decidual unit on day 5 of gestation and then to decline through day 9; transcripts remained elevated in the placenta between day 9 and day 13 (the latest day examined in this study). By use of specific enzyme histochemistry, most 5′‐NT activity was localized to the primary decidual zone on day 5. This expression subsequently declined during regression of the primary decidua; however, 5′‐NT appeared on giant trophoblast (days 7–13) and the metrial gland (days 11–13). Other purine catabolic enzymes degrading AMP (adenylate deaminase) or generating adenosine (S‐adenosylhomocysteine hydrolase) were not detected in the embryo‐decidual unit suggesting that the net flux of utero‐placental AMP catabolism proceeds with adenosine as an intermediate, this being the major pathway of adenosine formation. The sharp drop in adenosine levels between day 6 and day 7 coincided with a rise in the activity and mRNA expression of ADA, an enzyme which catalyzes the irreversible deamination of adenosine to inosine. ADA was previously localized to the secondary decidual zone (days 6–11), secondary giant cells (days 7–13), and spongiotrophoblasts (days 8–13) in the mouse (Knudsen et al., 1991). Results of developmental Northern blot analysis demonstrated a direct correlation of relative 5′‐NT/ADA mRNA band intensity to adenosine content between day 4 and day 9 of gestation, suggesting that the local availability of adenosine in the antimesometrium is dependent upon the distribution of these enzymatic activities. Purine nucleoside phosphorylase and xanthine oxidase, which are two catabolic enzymes acting subsequent to 5′‐NT and ADA in the sequential degradation of AMP to xanthine, remained low and constant in the tissues examined suggesting that the catabolic pathway is geared toward regulation of adenosine levels. These results suggest the establishment of an adenosine gradient across the developing antimesometrium. It is proposed that the source of adenosine is AMP released during uterine cell death, and that adenosine, in turn, serves as a regulatory signal to coordinate early postimplantation morphogenetic events with the progression of cell death at the uterine‐embryo interface.
16

Human Decidual CD8+ T Cells have Phenotypic and Functional Heterogeneity

Alexander, Aria January 2021 (has links)
No description available.
17

Ajustement biologique du mélèze aux variations environnementales le long d’un gradient altitudinal : approche microdensitométrique de la réponse au climat / Biological adjustment of larch to environmental variations along an altitudinal gradient : a wood microdensity approach of climate

Nardin, Maxime 29 November 2013 (has links)
La forte variation climatique, notamment de la température qui est associée à la distribution altitudinale de certains peuplements d’arbres forestiers peut induire des pressions de sélection divergentes favorisant l’expression de phénotypes différents en fonction de l’altitude. Cette thèse a pour objectif de déterminer si des adaptations locales existent et peuvent être mises en évidence dans un peuplement de mélèze (Larix decidua Mill.) distribué le long d’un gradient altitudinal situé dans les Alpes françaises, à proximité de Briançon. Quatre placettes d’environ 200 mélèzes ont été délimitées à 2300 m, 2000 m, 1700 m et 1350 m d’altitude le long de ce gradient. Une variabilité phénotypique significative a été observée entre ces niveaux altitudinaux pour la plupart des caractères étudiés : circonférence, hauteur de l’arbre, pourcentage d’aubier ainsi que pour toutes les variables microdensitométriques de cernes sauf une (la largeur de cerne). Une analyse de génétique des populations utilisant des marqueurs microsatellites a mis en évidence une faible influence de la dérive génétique sur la diversité génétique et une forte intensité de flux de gènes entre les différents niveaux altitudinaux étudiés. La différenciation génétique inter-altitudes a été estimée à l’aide d’une approche in-situ basée sur les données phénotypiques seules (PST) et comparée à la différenciation observée à l’aide des marqueurs microsatellites (FST). Cette analyse indique que l’hypothèse d’adaptations locales avec l’altitude peut être raisonnablement avancée pour les caractères de hauteur, circonférence, pourcentage d’aubier et densité du bois initial. Au contraire, l’adaptation locale n’apparait pas comme une hypothèse acceptable pour les caractères de largeur de cerne, surface de cerne, largeur du bois final et densité du bois final. / The strong climatic variation, in particular the temperature variation, which is associated with the altitudinal distribution of certain stands of forest trees, can induce different divergent selection pressure favoring altitude-dependent phenotype expression. The aim of the present thesis is to determine if local adaptation exists and can be identified in an European larch stand (Larix decidua Mill.) distributed along an altitudinal gradient located in the French Alps near Briançon. four plots of about 200 larches were delimited at 2300 m, 2000 m, 1700 m and 1350 m along this altitudinal gradient. A significant phenotypic variability was observed between these altitudinal levels for most characters studied: circumference, tree height, percentage of sapwood and for all the annual-ring microdensity variables except one (ring width). A population genetics analysis using microsatellite markers showed a small effect of genetic drift on the genetic diversity but an intensive gene flow between the altitudinal levels studied. The inter-altitudinal genetic differentiation was estimated using an in-situ approach based on phenotypic data only (PST) and compared with the differentiation observed by means of microsatellite markers (FST). This analysis indicates that the assumption of local adaptation with altitude can be reasonably proposed for the characters of height, circumference, percentage of sapwood and earlywood density. On the contrary, the local adaptation does not appear to be an acceptable assumption concerning characters such as ring width, ring surface area, latewood width and latewood density.
18

Expressão do fator de crescimento endotelial vascular (VEGF) e seus receptores VEGFR-1 e VEGFR-2 durante o início da gestação em camundongos. / Expression of vascular endothelial growth factor (VEGF) and its receptors VEGFR-1 and VEGFR-2 during early pregnancy in mice.

Silva, Luciana Oliveira da 28 May 2008 (has links)
Em roedores, o aumento da permeabilidade vascular, a transformação decidual, e angiogênese são eventos cruciais para o sucesso da gestação. O fator endotelial vascular (VEGF) é um mitogênico para células endoteliais e um indutor de angiogênese. O VEGF age via dois receptores da família das tirosina quinases: VEGFR1 e VEGFR2. O objetivo deste estudo foi investigar usando o método imunohistoquímico, a expressão espacial e temporal do VEGF e os receptores VEGFR1 e VEGFR2 em células endometriais de camundongo entre o 4º e 8º dias de gestação. No 4º dia de gestação, VEGF, VEGFR1 e VEGFR2 foram expressos pelo epitélio luminal e glandular e fracamente pelo estroma endometrial. Do 5º ao 8º dias de gestação, o VEGF foi expresso nas células deciduais mesometriais. VEGFR1 e VEGFR2 foram expresso pelas células do epitélio luminal e glandular e mostraram uma marcação diferencial na decídua mesometrial e antimesometrial. Os receptores VEGFR1 e VEGFR2 foram intensamente expressos pelas células endoteliais dos capilares sinusóides mesometriais e pelas células Nk uterinas. / In rodents, increase of vascular permeability, decidual cell transformation, and uterine angiogenesis are crucial events for the success of pregnancy. Vascular endothelial growth factor (VEGF) is a mitogen for endothelial cells and an inducer of angiogenesis. VEGF acts via two tyrosine kinase family receptors: VEGFR1 and VEGFR2. The aim of this study was to investigate using the immunohistochemical method, the spatiotemporal expression of VEGF and its receptors VEGFR1 e VEGFR2 by mouse endometrial cells on days 4 to 8 of pregnancy. On day 4, VEGF, VEGFR1 and VEGFR2 were expressed mostly by the luminal and glandular epithelium. Stromal cells showed a very weak labeling. On days 5-8, VEGF and its receptors showed an increased labeling throughout the mesometrial decidua. The expression of VEGF, VEGFR1, and VEGFR2 were differentially expressed in the mesometrial cells and in the predecidual cells of the antimesometrial decidua. VEGFR1 and VEGF R2 were highly expressed by endothelial cells of the mesometrial sinusoids, and Nk uterine cells.
19

Expressão do fator de crescimento endotelial vascular (VEGF) e seus receptores VEGFR-1 e VEGFR-2 durante o início da gestação em camundongos. / Expression of vascular endothelial growth factor (VEGF) and its receptors VEGFR-1 and VEGFR-2 during early pregnancy in mice.

Luciana Oliveira da Silva 28 May 2008 (has links)
Em roedores, o aumento da permeabilidade vascular, a transformação decidual, e angiogênese são eventos cruciais para o sucesso da gestação. O fator endotelial vascular (VEGF) é um mitogênico para células endoteliais e um indutor de angiogênese. O VEGF age via dois receptores da família das tirosina quinases: VEGFR1 e VEGFR2. O objetivo deste estudo foi investigar usando o método imunohistoquímico, a expressão espacial e temporal do VEGF e os receptores VEGFR1 e VEGFR2 em células endometriais de camundongo entre o 4º e 8º dias de gestação. No 4º dia de gestação, VEGF, VEGFR1 e VEGFR2 foram expressos pelo epitélio luminal e glandular e fracamente pelo estroma endometrial. Do 5º ao 8º dias de gestação, o VEGF foi expresso nas células deciduais mesometriais. VEGFR1 e VEGFR2 foram expresso pelas células do epitélio luminal e glandular e mostraram uma marcação diferencial na decídua mesometrial e antimesometrial. Os receptores VEGFR1 e VEGFR2 foram intensamente expressos pelas células endoteliais dos capilares sinusóides mesometriais e pelas células Nk uterinas. / In rodents, increase of vascular permeability, decidual cell transformation, and uterine angiogenesis are crucial events for the success of pregnancy. Vascular endothelial growth factor (VEGF) is a mitogen for endothelial cells and an inducer of angiogenesis. VEGF acts via two tyrosine kinase family receptors: VEGFR1 and VEGFR2. The aim of this study was to investigate using the immunohistochemical method, the spatiotemporal expression of VEGF and its receptors VEGFR1 e VEGFR2 by mouse endometrial cells on days 4 to 8 of pregnancy. On day 4, VEGF, VEGFR1 and VEGFR2 were expressed mostly by the luminal and glandular epithelium. Stromal cells showed a very weak labeling. On days 5-8, VEGF and its receptors showed an increased labeling throughout the mesometrial decidua. The expression of VEGF, VEGFR1, and VEGFR2 were differentially expressed in the mesometrial cells and in the predecidual cells of the antimesometrial decidua. VEGFR1 and VEGF R2 were highly expressed by endothelial cells of the mesometrial sinusoids, and Nk uterine cells.
20

PTBP1 Is Required for Embryonic Development before Gastrulation

Solimena, Michele, Suckale, Jakob, Wendling, Olivia, Masjkur, Jimmy, Jäger, Melanie, Münster, Carla, Anastassiadis, Konstantinos, Stewart, A. Francis 07 January 2016 (has links) (PDF)
Polypyrimidine-tract binding protein 1 (PTBP1) is an important cellular regulator of messenger RNAs influencing the alternative splicing profile of a cell as well as its mRNA stability, location and translation. In addition, it is diverted by some viruses to facilitate their replication. Here, we used a novel PTBP1 knockout mouse to analyse the tissue expression pattern of PTBP1 as well as the effect of its complete removal during development. We found evidence of strong PTBP1 expression in embryonic stem cells and throughout embryonic development, especially in the developing brain and spinal cord, the olfactory and auditory systems, the heart, the liver, the kidney, the brown fat and cartilage primordia. This widespread distribution points towards a role of PTBP1 during embryonic development. Homozygous offspring, identified by PCR and immunofluorescence, were able to implant but were arrested or retarded in growth. At day 7.5 of embryonic development (E7.5) the null mutants were about 5x smaller than the control littermates and the gap in body size widened with time. At mid-gestation, all homozygous embryos were resorbed/degraded. No homozygous mice were genotyped at E12 and the age of weaning. Embryos lacking PTBP1 did not display differentiation into the 3 germ layers and cavitation of the epiblast, which are hallmarks of gastrulation. In addition, homozygous mutants displayed malformed ectoplacental cones and yolk sacs, both early supportive structure of the embryo proper. We conclude that PTBP1 is not required for the earliest isovolumetric divisions and differentiation steps of the zygote up to the formation of the blastocyst. However, further post-implantation development requires PTBP1 and stalls in homozygous null animals with a phenotype of dramatically reduced size and aberration in embryonic and extra-embryonic structures.

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