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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

Bullous pemphigoid: Use of C4d Immunofluorescent Staining in a Case With Repeated Negative Conventional Direct Immunofluorescence Studies

Kassaby, Sarah S., Hicks, Alexander, Leicht, Stuart, Youngberg, George A. 01 January 2017 (has links)
Direct immunofluorescence (DIF) using frozen section material from a fresh/preserved perilesional biopsy is the gold standard for the immunopathologic diagnosis of bullous pemphigoid (BP). DIF in BP shows linear dermoepidermal junction (DEJ) staining for C3, with or without staining for IgG. In some situations, only a formalin-fixed lesional biopsy is obtained (with no fresh/preserved perilesional biopsy for DIF). In this setting, paraffin section C4d immunohistochemistry has proven to be diagnostically useful, demonstrating linear DEJ positivity for C4d. We present a novel use of C4d staining for the diagnosis of BP, specifically analyzing C4d perilesional frozen section DIF in a case where standard perilesional frozen section DIF for IgG/C3 was available, but was negative. An 80-year-old woman presented with a pruritic bullous lesion on her left upper extremity, clinically thought to represent BP. Lesional histologic findings were typical for BP, but perilesional frozen section DIF staining was negative for IgG and C3. A second set of biopsies processed at a different laboratory yielded the same result. A diagnosis of bullous scabies was considered. Subsequently, perilesional frozen section DIF for C4d was obtained, which showed strong linear DEJ positivity, confirming the diagnosis of BP. DIF for C4d is widely used in transplant pathology, since C4d is persistent in tissue, versus C3. Our case demonstrates that perilesional frozen section DIF staining for C4d may be positive and diagnostic in BP, even when conventional DIF staining for IgG and C3 is negative.
12

From in situ to in vitro: measuring contact-dependent determinants of human natural killer cell development

Hegewisch Solloa, Everardo January 2023 (has links)
Human natural killer (NK) cells are found in virtually all tissues where they act as a first line defense against malignant and virally infected cells. The development of NK cells from CD34+ hematopoietic progenitors is a complex process that involves navigating through different microenvironments and requires contact-dependent interactions with stromal cells. The molecular mediators of NK cell developmental subset trafficking, cell-cell interactions, and maturation have not been fully characterized. This thesis presents 3 studies that aim to uncover contact-dependent interactions that drive human NK cell development. Chapter 2 focuses on defining the adhesome profile of human NK cells from in vitro derived populations, tonsil, and peripheral blood. This study reveals that the tissue origin and developmental stage of NK cells influence the expression of adhesome-associated genes and proteins, as well as the content of cortical actin, which suggests a link between adhesome expression and actin regulation in NK cells. Chapter 3 presents the first comprehensive study on human NK cell development in pediatric tonsil using cyclic immunofluorescence microscopy and imaging mass cytometry. We reveal that NK cell subset localization and interactions are dependent on NK cell developmental stage and tissue residency. Chapter 4 demonstrates that neural cell adhesion molecule (NCAM) on stromal cells promotes maintenance of a mesenchymal-like state and subsequently the survival and proliferation of human NK cell precursors. Overall, this thesis provides new insights on previously unknown mediators of NK cell contact-dependent interactions and unveils the first road map of in situ NK cell development.
13

Expression et localisation du système endocannabinoïde dans la rétine du singe

Bouskila, Joseph Meyer 09 1900 (has links)
Les effets de la marijuana, un médicament utilisé par l’homme depuis des millénaires, sur le système visuel sont peu connus. Une meilleure connaissance de la distribution du système endocannabinoïde (eCB) de la rétine pourrait expliquer comment cette drogue affecte la vision. Cette étude vise à caractériser la distribution du récepteur cannabinoïde CB1 (CB1R) et de l’enzyme de dégradation FAAH (“fatty acid amide hydrolase”) des ligands du CB1R dans la rétine du singe Vert (Chlorocebus sabaeus). De plus, elle vise à déterminer quelles sous-populations cellulaires de la rétine expriment ces composantes. La plupart des études à ce jour ont été conduites surtout sur les rongeurs et peu de travaux ont été réalisés chez le singe. Notre étude vient donc combler cette carence. Par le biais de méthodes immunohistochimiques, nous avons investigué la localisation du CB1R et de l’enzyme FAAH à différentes excentricités rétiniennes, de la fovéa centralis vers la périphérie. Nos résultats, en accord avec notre hypothèse de travail, démontrent que CB1R et FAAH sont exprimés à travers toute la rétine mais avec, cependant, des différences notoires. Au niveau de la couche des photorécepteurs, CB1R est exprimé préférentiellement dans les cônes et ce patron d’expression suit la distribution des photorécepteurs centre-périphérie. De plus, CB1R se retrouve surtout dans les pédicules des cônes de la couche plexiforme externe. CB1R et FAAH sont abondants dans les cellules bipolaires tant au centre qu’en périphérie. Le soma et l’axone des cellules ganglionnaires expriment aussi CB1R et FAAH. Ces données suggèrent que le système eCB est présent à travers toute la rétine du primate et pourrait expliquer les perturbations visuelles entrainées par la marijuana, telles la photosensibilité et la vision des couleurs. / The effects of marijuana, a drug that has been used by men for millennia, on the visual system are poorly understood. A better understanding of the distribution of the endocannabinoid system in the retina will help us explain how this drug affects vision. This study aims at characterizing the distribution of the endocannabinoid receptor CB1 (CB1R) and the enzyme degrading CB1R ligands, fatty acid amide hydrolase (FAAH) throughout the Green monkey retina (Chlorocebus sabaeus). In addition, it seeks to determine which sub-population of neurons expresses CB1R and the degrading enzyme FAAH. Most data on the endocannabinoid system have been acquired in rodents and studies on monkeys are rather scarce. We attempted to fill this void by using immunohistochemical methods to locate CB1R and FAAH at various eccentricities of the monkey retina, from the center to the far periphery. Our results, in agreement with our hypothesis, demonstrate that CB1R and FAAH are expressed throughout the retina. At the level of the photoreceptors, CB1R is expressed preferentially in cones rather than in rods, and this expression pattern follows the photoreceptors distribution. In the outer plexiform layer, CB1R immunoreactivity is predominantly concentrated in the cone pedicles. Although foveal cones are the main expressers of both CB1R and FAAH, these are also found in rod bipolar cells. The ganglion cell axons strongly express the CB1 receptor and the enzyme FAAH. These data suggest that the presence of CB1R throughout the retina may be responsible for the visual effects commonly reported by cannabis users, such as the increase in photosensitivity and alterations in color discrimination.
14

Expression et localisation du système endocannabinoïde dans la rétine du singe

Bouskila, Joseph M. 09 1900 (has links)
Les effets de la marijuana, un médicament utilisé par l’homme depuis des millénaires, sur le système visuel sont peu connus. Une meilleure connaissance de la distribution du système endocannabinoïde (eCB) de la rétine pourrait expliquer comment cette drogue affecte la vision. Cette étude vise à caractériser la distribution du récepteur cannabinoïde CB1 (CB1R) et de l’enzyme de dégradation FAAH (“fatty acid amide hydrolase”) des ligands du CB1R dans la rétine du singe Vert (Chlorocebus sabaeus). De plus, elle vise à déterminer quelles sous-populations cellulaires de la rétine expriment ces composantes. La plupart des études à ce jour ont été conduites surtout sur les rongeurs et peu de travaux ont été réalisés chez le singe. Notre étude vient donc combler cette carence. Par le biais de méthodes immunohistochimiques, nous avons investigué la localisation du CB1R et de l’enzyme FAAH à différentes excentricités rétiniennes, de la fovéa centralis vers la périphérie. Nos résultats, en accord avec notre hypothèse de travail, démontrent que CB1R et FAAH sont exprimés à travers toute la rétine mais avec, cependant, des différences notoires. Au niveau de la couche des photorécepteurs, CB1R est exprimé préférentiellement dans les cônes et ce patron d’expression suit la distribution des photorécepteurs centre-périphérie. De plus, CB1R se retrouve surtout dans les pédicules des cônes de la couche plexiforme externe. CB1R et FAAH sont abondants dans les cellules bipolaires tant au centre qu’en périphérie. Le soma et l’axone des cellules ganglionnaires expriment aussi CB1R et FAAH. Ces données suggèrent que le système eCB est présent à travers toute la rétine du primate et pourrait expliquer les perturbations visuelles entrainées par la marijuana, telles la photosensibilité et la vision des couleurs. / The effects of marijuana, a drug that has been used by men for millennia, on the visual system are poorly understood. A better understanding of the distribution of the endocannabinoid system in the retina will help us explain how this drug affects vision. This study aims at characterizing the distribution of the endocannabinoid receptor CB1 (CB1R) and the enzyme degrading CB1R ligands, fatty acid amide hydrolase (FAAH) throughout the Green monkey retina (Chlorocebus sabaeus). In addition, it seeks to determine which sub-population of neurons expresses CB1R and the degrading enzyme FAAH. Most data on the endocannabinoid system have been acquired in rodents and studies on monkeys are rather scarce. We attempted to fill this void by using immunohistochemical methods to locate CB1R and FAAH at various eccentricities of the monkey retina, from the center to the far periphery. Our results, in agreement with our hypothesis, demonstrate that CB1R and FAAH are expressed throughout the retina. At the level of the photoreceptors, CB1R is expressed preferentially in cones rather than in rods, and this expression pattern follows the photoreceptors distribution. In the outer plexiform layer, CB1R immunoreactivity is predominantly concentrated in the cone pedicles. Although foveal cones are the main expressers of both CB1R and FAAH, these are also found in rod bipolar cells. The ganglion cell axons strongly express the CB1 receptor and the enzyme FAAH. These data suggest that the presence of CB1R throughout the retina may be responsible for the visual effects commonly reported by cannabis users, such as the increase in photosensitivity and alterations in color discrimination.
15

Preprodynorphin-Expressing Neurons Constitute a Large Subgroup of Somatostatin-Expressing GABAergic Interneurons in the Mouse Neocortex / マウス大脳新皮質ソマトスタチン陽性抑制性細胞の約半数は、プレプロダイノルフィンを発現する

Sohn, Jaerin 23 March 2016 (has links)
The version posted must include the following notice on the first page: This is the peer reviewed version of the following article: http://onlinelibrary.wiley.com/doi/10.1002/cne.23477/abstract, which has been published in final form at DOI: 10.1002/cne.23477. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. / 京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19610号 / 医博第4117号 / 新制||医||1015(附属図書館) / 32646 / 京都大学大学院医学研究科医学専攻 / (主査)教授 渡邉 大, 教授 髙橋 良輔, 教授 宮本 享 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
16

AUTORADIOGRAPHIC AND IMMUNOFLUORESCENT DETECTION OF LOW CONCENTRATIONS OF ACTINOMYCIN D BOUND TO HUMAN METAPHASE CHROMOSOMES.

BROTHMAN, ARTHUR RICHARD. January 1982 (has links)
The binding of low concentrations of actinomycin D (Act D) to fixed human metaphase chromosomes was studied using both autoradiographic and immunofluorescent techniques. At the concentration range of 0.001 - 0.1 μg/ml Act D is known to selectively inhibit rRNA synthesis. Although it was previously suggested that at these low concentrations Act D would selectively bind to the ribosomal cistrons, evidence also exists that the drug binds to non-ribosomal DNA, and inhibits rRNA transcription in an indirect fashion. Because of the conflicting data on Act D binding and a lack of focus on biologically relevant concentrations of drug, it was decided to systematically investigate the distribution of the drug binding in low concentrations to chromosomes from 72-hr human lymphocyte cultures. Autoradiographic detection of [³H]Act D bound to chromosomes showed no selective binding of the drug at concentrations that maximally inhibit rRNA synthesis. A new technique was employed using Formvar and potassium chromium sulfate as a pretreatment to autoradiography. This technique permitted simultaneous detection of silver grains and chromosome identification by G-banding. With autoradiographic exposure times of 1 and 7 days, there was a positive correlation of autoradiographic grains with chromosome length. To increase sensitivity in detection of Act D bound to chromosomes, a specific anti-Act D antibody was generated in rabbits. Antibody avidity was evaluated on the basis of a rapid charcoal assay. This charcoal assay was then used in development of a radioimmunoassay for Act D which is sensitive in quantitating the drug down to 0.005 μg/ml. The anti-Act D antibody was characterized to be IgG, and was shown to be specific for the pentapeptide lactone portion of the Act D molecule. Indirect immunofluorescence of Protein A-purified IgG containing anti-Act D was used to detect drug bound to fixed human chromosomes. The antibody was shown to be specific for drug bound to chromatin. When 0.1 μg/ml Act D was bound to chromosomes, the drug was observed bound throughout the genome, with no selective binding at the ribosomal cistrons. This confirms the autoradiographic data and supports the model of extranucleolar regulation of rRNA synthesis. Preliminary results suggest that Act D binds to GC-rich DNA, since an R-banding pattern was observed in 5% of the immunofluorescent metaphases examined.
17

Étude sur la contamination du colostrum bovin par des ookystes de Cryptosporidium parvum

Baillargeon, Julie January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
18

Stress and GABAA receptor regulation

Skilbeck, Kelly Johanne January 2009 (has links)
Doctor of Philosophy (PhD) / GABAA receptors are implicated in the pathology of psychiatric disorders such as schizophrenia and depression. They are rapidly affected by stress in a sex-dependent fashion, suggesting that GABAA receptors may be relevant to understanding the association between stress and psychiatric disorders. Thus, this thesis examined how GABAA receptors are affected in both male and female mice exposed to stress in adulthood (Chapter 2), early-life (Chapter 3-5) and a combination of both early-life and adulthood stress (Chapter 6). 2. The effects of acute adulthood stress (3 minute warm swim stress) on GABAA receptor binding in the brains of male and female mice were examined using quantitative receptor autoradiography. The total number of GABAA receptor [3H]GABA binding sites was increased following swim stress in specific forebrain cortical regions of female mice swum individually or in a group, but decreased in male mice when swum in a group only. These findings confirm and extend previous studies, identifying the cortical regions involved in rapid stress-induced changes in GABAA receptors. 3. Post-natal handling models in rodents comparing control (brief handling sessions; EH) with no intervention stress conditions (NH), indicate that the NH condition results in an anxious adulthood phenotype and this was confirmed in the present thesis using the elevated plus-maze behavioural test. Using this model the effects of early-life stress on adulthood GABAA receptors were then examined. 4. Regional densities of GABAA receptor α1 and α2 subunit proteins were observed in the adult brain of male and female mice using immunoperoxidase histochemistry. NH males showed a loss of the α2 subunit from the thalamus and the lower layers (IV-VI) of the primary somatosensory cortex, whilst NH females showed a reduction of α2 but an increase in α1 protein in the lower layers of the primary somatosensory cortex only. These regionally specific alterations in the α1:α2 subunit ratio suggest that early-life stress disrupts the developmental α subunit switch, which occurs in a regionally-dependent fashion over the first two weeks of rodent life. 5. Double-labelling immunofluorescence and confocal microscopy were used to examine the effects of sex and early-life stress on GABAA receptor synaptic clustering. Regardless of sex, mice exposed to early-life stress (NH) showed reduced colocalisation of the GABAA receptor α2 subunit with the synaptic marker protein gephyrin relative to the control condition (EH). This suggests that early-life stress impairs adulthood inhibitory synaptic strength and is consistent with the increased anxiety of the stressed relative to control mice. 6. Finally, the effects of early-life stress on adulthood swim stress-induced changes in GABAA receptor binding were examined using quantitative receptor autoradiography in forebrain cortical regions. Findings showed that the effect of adulthood stress on the total number of GABAA receptor binding sites for [3H]GABA in forebrain cortical regions was altered by early-life stress in both male and female mice, suggesting that the rapid adulthood stress response of GABAA receptors is affected by early-life experience. 7. Together these results show that GABAA receptors are sensitive to subtle changes in the environment in both early-life and adulthood and that these neurochemical responses to stress in adulthood are sex-dependent. The short and long-term stress-sensitivity of the GABAergic system implicates GABAA receptors in the non-genetic aetiology of psychiatric illnesses in which sex and stress are important factors.
19

Molecular epidemiology of Trypanosoma (Herpetosoma) rangeli (Kinetoplastida: Trypanosomatidae) in Ecuador, South America, and study of the parasite cell invasion mechanism in vitro

Lascano, Segundo Mauricio. January 2009 (has links)
Thesis (Ph.D.)--Ohio University, November, 2009. / Release of full electronic text on OhioLINK has been delayed until December 1, 2010. Title from PDF t.p. Includes bibliographical references.
20

Comparison between tissue-based indirect immunofluorescence andenzyme-linked immunosorbent assays, two detection methods for anti-aquaporin-4 antibodies in neuromyelitis optica spectrum disorders

Lo, Yuk-fai., 盧育輝. January 2011 (has links)
published_or_final_version / Medicine / Master / Master of Medical Sciences

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