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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.
21

Siliciumorganische Wirkstoffe : Synthese und pharmakologische Eigenschaften siliciumhaltiger Muscarin-, Dopamin- und alpha1-Rezeptor-Antagonisten sowie Ca2+-Kanal-Blocker / synthesis and pharmacological characterization of silicon-containing muscarinic antagonists, dopamine receptor antagonists, Ca2+ channel blockers, and alpha1-adrenoceptor antagonists

Heinrich, Tilman January 2004 (has links) (PDF)
Im Rahmen der vorliegenden Arbeit wurden neuartige siliciumhaltige Muscarinrezeptor-Antagonisten, Dopaminrezeptor-Antagonisten, Ca2+-Kanal-Blocker sowie alpha1-Rezeptor-Antagonisten synthetisiert, welche Sila-Analoga (C/Si-Austausch) bekannter organischer Pharmaka darstellen. Die C/Si-Analoga wurden pharmakologisch charakterisiert und damit Beiträge zur Thematik der C/Si-Bioisosterie geleistet. / In this work novel silicon-containing muscarinic antagonists, dopamine receptor antagonists, Ca2+ channel blockers, and alpha1-adrenoceptor antagonists – representing sila-analogues (C/Si replacement) of known organic drugs – were synthesized and pharmacologically characterized (studies on C/Si bioisosterism).
22

Investigação funcional e molecular dos adrenoceptores alfa-1 em modelo experimental de epididimite em ratos

Mueller, Andre January 2019 (has links)
Orientador: André Sampaio Pupo / Resumo: Primordialmente, o epidídimo funciona para proteger e realizar a maturação de espermatozoides. A cauda do epidídimo (CE), região que armazena espermatozoides maduros até a ejaculação, recebe densa inervação de fibras pós-ganglionares simpáticas que liberam noradrenalina para contrair o músculo liso do epidídimo via ativação de adrenoceptores alfa-1A (alfa-1A-ARs). As contrações da musculatura lisa têm papel importante no transporte dos espermatozoides ao longo do ducto epididimário, bem como na contração da CE distal durante a fase de emissão seminal da ejaculação. Recentemente, foi demonstrado que a epididimite, a condição inflamatória do epidídimo, induz aceleração do tempo de trânsito espermático em ratos. Nesta tese, testamos a hipótese de que essa aceleração do trânsito espermático induzida pela epididimite é resultado de alterações na contratilidade do ducto epididimário. Dessa forma, o objetivo deste estudo foi investigar a contração da CE distal mediada por alfa-1-ARs em um modelo experimental de epididimite aguda induzida pelo lipopolissacarídeo (LPS) de E. coli em ratos. Após 6 e 24 h da injeção intraductal de LPS (25 µg) para indução da epididimite (in vivo), estudos de contração indicaram que a potência da noradrenalina aumentou ~6 vezes na CE distal inflamada. As contrações induzidas pela noradrenalina foram competitivamente antagonizadas pelo prazosin, um antagonista não-seletivo de alfa-1-ARs, com afinidades semelhantes nos grupos tratados com LPS e salina (pA2... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The epididymis works primarly to protect and mature the spermatozoon. The cauda epididymis (CE), which stores mature spermatozoa until ejaculation, is densely innervated by sympathetic postganglionic fibers that release noradrenaline to contract epididymal smooth muscle via activation of alpha-1A adrenoceptors (1A-ARs). The smooth muscle contractions have an important role for the adequate transport of spermatozoa within the epididymal duct, as well as for distal CE contraction during the seminal emission phase of ejaculation. It was recently shown that epididymitis, the inflammatory condition of the epididymis, induces acceleration of the sperm transit time in the rat epididymis. We hypothesize that this epididymitis-induced sperm transit time acceleration is due to changes in the contractility of the epididymal duct. Thus, the aim of this study was to investigate the 1-ARs-mediated contraction of the distal CE in an experimental model of acute epididymitis in rats induced by lipopolysaccharide (LPS) from E. coli. Contraction studies indicated that the potency of noradrenaline increased ~6-fold in the inflamed distal CE at 6 h post-intravasal LPS injection. Noradrenaline-induced contractions were competitively antagonized by prazosin, a non-selective 1-ARs antagonist, with similar affinities in both LPS- and saline-treated groups (pA28.9). However, the potency of BMY 7378, a selective 1D-ARs antagonist, was ~50-fold higher in the distal CE treated with LPS (pA2 LPS = 8.... (Complete abstract click electronic access below) / Doutor
23

Increasing Knowledge About Alpha-1 Antitrypsin Deficiency in the Chronic Obstructive Pulmonary Disease Population

Barta, Maureen Ann Wentink 01 January 2015 (has links)
The purpose of the project was to increase awareness about alpha-1 antitrypsin deficiency (AATD) in chronic obstructive pulmonary disease (COPD), particularly among those with a familial history of genetic factor AATD; an additional goal was to understand its relationship to COPD. COPD is the third leading cause of death in the United States, with more than half of COPD patients experiencing significant disabilities. Major causes for COPD include smoking, air pollution, secondary smoke, upper respiratory infections, hereditary factors, occupational factors, environmental factors, and socioeconomic factors. Genetic factors, however, also play a significant role in early onset COPD and in those who smoke and have the genetic factor related to COPD (AATD), symptoms are more severe and exacerbations more frequent. Undiagnosed AATD can result in under treatment and lack of planning for preventing COPD onset and exacerbation in these patients. COPD clients of a local pharmacy (n =31) were invited to complete a Likert survey and given materials on COPD exacerbation prevention and information on AATD. Results indicated that 38.7% of respondents had early onset symptoms, positive family history, and no improvement in symptoms with smoking cessation. The results support that targeting those family members with COPD and providing information on genetic factors for this condition could decrease the frequency and severity of exacerbations. This is in keeping with the health belief model that guided this study in that a perceived risk for harm has the potential to improve the use of preventative health measures in individuals.
24

Comparison of several protocols for the increase in homologous recombination in normal porcine fetal fibroblasts and the application to an actual locus

Zaunbrecher, Gretchen Marie 30 September 2004 (has links)
Together with the advancements in animal cloning, the ability to efficiently target specific genes in somatic cells would greatly enhance several areas of research. While it has been possible for quite some time to target specific genes in the germ cells of mice, the advancements in somatic cell gene targeting has been slowed for two main reasons. First, the finite lifespan of somatic cells, due mainly to the inability of the somatic cells to regenerate or maintain their telomeres, poses a major problem given the lengthy selection process needed to identify a targeting event. The second problem is the overall inefficiency of homologous recombination. A double strand break or introduction of foreign DNA into a cell can be processed either through the homologous recombination or non-homologous end joining pathways. Of these two, non-homologous end joining is dominant in somatic cells. A two plasmid recombination system was used to study the effects of the manipulation of several non-homologous end joining and homologous recombination pathway molecules on the rates of homologous recombination in porcine fetal fibroblasts. In addition, the effect of telomerase expression, cell synchrony, and DNA nuclear delivery was examined. Results indicate a strong positive relationship between inactivation of p53, cell synchronization, and efficient DNA nuclear delivery in enhancing the rate of homologous recombination. These findings were then applied to an actual locus in the pig, the α1,3 galactosyltransferase gene. Results from these transfections are compared to published accounts of successful targeting at this locus and possibilities for the differences found are discussed.
25

The Effect of Alpha 1-Antitrypsin on Ischemia-Reperfusion Injury in Lung Transplantation

Gao, Wenxi 20 November 2012 (has links)
Ischemia-reperfusion (IR) injury is a severe complication in lung transplantation characterized by inflammation, alveolar damage, and hypoxemia. Alpha 1-antitrypsin (A1AT), a protease inhibitor, is currently used clinically for the treatment of A1AT deficiency emphysema. A1AT has been shown to have the potential to reduce IR injury through its anti-inflammatory and anti-apoptotic effects. We hypothesized that A1AT will ameliorate IR injury through these effects. We tested A1AT in two models of IR: a cell culture model of simulated lung transplantation and a rat in situ pulmonary ligation model. In cell culture, we found that A1AT exerts its protective effects by inhibiting cell death and inflammatory cytokine release in a dose-dependent manner. In the rat pulmonary ischemia-reperfusion model, we found that A1AT improved lung function by inhibiting apoptosis and inflammation. There is potential for future application of A1AT in the treatment of IR injury in lung transplantation.
26

The Effect of Alpha 1-Antitrypsin on Ischemia-Reperfusion Injury in Lung Transplantation

Gao, Wenxi 20 November 2012 (has links)
Ischemia-reperfusion (IR) injury is a severe complication in lung transplantation characterized by inflammation, alveolar damage, and hypoxemia. Alpha 1-antitrypsin (A1AT), a protease inhibitor, is currently used clinically for the treatment of A1AT deficiency emphysema. A1AT has been shown to have the potential to reduce IR injury through its anti-inflammatory and anti-apoptotic effects. We hypothesized that A1AT will ameliorate IR injury through these effects. We tested A1AT in two models of IR: a cell culture model of simulated lung transplantation and a rat in situ pulmonary ligation model. In cell culture, we found that A1AT exerts its protective effects by inhibiting cell death and inflammatory cytokine release in a dose-dependent manner. In the rat pulmonary ischemia-reperfusion model, we found that A1AT improved lung function by inhibiting apoptosis and inflammation. There is potential for future application of A1AT in the treatment of IR injury in lung transplantation.
27

Increasing Knowledge About Alpha-1 Antitrypsin Deficiency in the Chronic Obstructive Pulmonary Disease Population

Barta, Maureen Ann Wentink 01 January 2015 (has links)
Walden University College of Health Sciences This is to certify that the doctoral study by Maureen Barta has been found to be complete and satisfactory in all respects, and that any and all revisions required by the review committee have been made. Review Committee Dr. Cheryl Holly, Committee Chairperson, Health Services Faculty Dr. Eric Anderson, Committee Member, Health Services Faculty Dr. Vincent Hall, University Reviewer, Health Services Faculty Chief Academic Officer Eric Riedel, Ph.D. Walden University 2015 â?? Increasing Knowledge About Alpha-1 Antitrypsin Deficiency in the Chronic Obstructive Pulmonary Disease Population by Maureen Ann Wentink Barta MSN, Pacific Lutheran University, 1996 BSN, Pacific Lutheran University, 1992 Project Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Nursing Practice Walden University November 2015 â?? The purpose of the project was to increase awareness about alpha-1 antitrypsin deficiency (AATD) in chronic obstructive pulmonary disease (COPD), particularly among those with a familial history of genetic factor AATD; an additional goal was to understand its relationship to COPD. COPD is the third leading cause of death in the United States, with more than half of COPD patients experiencing significant disabilities. Major causes for COPD include smoking, air pollution, secondary smoke, upper respiratory infections, hereditary factors, occupational factors, environmental factors, and socioeconomic factors. Genetic factors, however, also play a significant role in early onset COPD and in those who smoke and have the genetic factor related to COPD (AATD), symptoms are more severe and exacerbations more frequent. Undiagnosed AATD can result in under treatment and lack of planning for preventing COPD onset and exacerbation in these patients. COPD clients of a local pharmacy (n =31) were invited to complete a Likert survey and given materials on COPD exacerbation prevention and information on AATD. Results indicated that 38.7% of respondents had early onset symptoms, positive family history, and no improvement in symptoms with smoking cessation. The results support that targeting those family members with COPD and providing information on genetic factors for this condition could decrease the frequency and severity of exacerbations. This is in keeping with the health belief model that guided this study in that a perceived risk for harm has the potential to improve the use of preventative health measures in individuals.
28

Comparison of several protocols for the increase in homologous recombination in normal porcine fetal fibroblasts and the application to an actual locus

Zaunbrecher, Gretchen Marie 30 September 2004 (has links)
Together with the advancements in animal cloning, the ability to efficiently target specific genes in somatic cells would greatly enhance several areas of research. While it has been possible for quite some time to target specific genes in the germ cells of mice, the advancements in somatic cell gene targeting has been slowed for two main reasons. First, the finite lifespan of somatic cells, due mainly to the inability of the somatic cells to regenerate or maintain their telomeres, poses a major problem given the lengthy selection process needed to identify a targeting event. The second problem is the overall inefficiency of homologous recombination. A double strand break or introduction of foreign DNA into a cell can be processed either through the homologous recombination or non-homologous end joining pathways. Of these two, non-homologous end joining is dominant in somatic cells. A two plasmid recombination system was used to study the effects of the manipulation of several non-homologous end joining and homologous recombination pathway molecules on the rates of homologous recombination in porcine fetal fibroblasts. In addition, the effect of telomerase expression, cell synchrony, and DNA nuclear delivery was examined. Results indicate a strong positive relationship between inactivation of p53, cell synchronization, and efficient DNA nuclear delivery in enhancing the rate of homologous recombination. These findings were then applied to an actual locus in the pig, the α1,3 galactosyltransferase gene. Results from these transfections are compared to published accounts of successful targeting at this locus and possibilities for the differences found are discussed.
29

Étude du récepteur nucléaire FXR en contexte épithélial intestinal : activité et régulation de l'expression 3

Leclerc, Simon January 2012 (has links)
Le récepteur nucléaire FXR (NR1H4) possède quatre isoformes exprimés principalement dans le foie (FXR[alpha]1 et FXR[alpha]2) et dans l'intestin (FXR[alpha]3 et FXR[alpha]4). Le rôle de FXR dans l'homéostasie des acides biliaires au sein du système digestif est bien documenté. Récemment, de nouvelles fonctions ont été attribuées à FXR dans l'intestin et une étude de ChIP-seq montre que les sites de liaison de FXR dans le génome diffèrent entre le foie et l'intestin. Notre hypothèse de recherche est que FXR contribue au maintien d'un épithélium intestinal intègre et fonctionnel en influençant des processus biologiques autres que la régulation de l'absorption des acides biliaires, et ce, par l'activation de la transcription de nouveaux gènes cibles dans l'intestin. Notre premier objectif consistait en l'identification de nouvelles cibles transcriptionnelles de FXR. Le modèle cellulaire Caco-2/15 est utilisé comme modèle d'entérocytes différenciés et l'expression de FXR augmente lors de la différenciation de ces cellules pour atteindre un niveau maximal vers 20 jours post-confluence. Dans ces cellules bien différenciées, une expérience de micro-puce à ADN révèle que l'activation de FXR par son agoniste synthétique le GW 4064 module significativement l'expression de gènes associés à différents processus biologiques tels l'organisation du cytosquelette et l'adhésion biologique. Nous avons confirmé que l'expression des gènes des protéines structurales MYO1A, MYO7A et DST est régulée positivement par l'activation de FXR, sans doute de manière indirecte puisque nous n'avons pas observé par ChIP que FXR se liait au promoteur de ces gènes. Pour identifier de nouvelles cibles directes de FXR, un criblage par qPCR selon divers critères a été réalisé. Ainsi, nous avons confirmé que le gène de SLC20A1, un transporteur de phosphore, est régulé positivement par l'activation de FXR. De plus, selon nos essais de ChIP, FXR se lie au promoteur de SLC20A1 suggérant une activation directe de la transcription. Ces résultats ouvrent la voie à un rôle auparavant insoupçonné de FXR dans des processus liés à l'absorption du phosphore. Notre deuxième objectif qui était d'étudier la régulation de l'expression différentielle des isoforme de FXR a été réalisé par des essais luciférase et nous amène à croire que le promoteur des isoformes intestinaux est régulé par la présence du facteur de transcription Cdx2. En effet, le promoteur FXR[alpha]3/[alpha]4 présente un site de liaison à Cdx2 contrairement au promoteur FXR[alpha]1/[alpha]2. De plus, en contexte où les facteurs hépatiques et intestinaux HNF1[alpha] et HNF4[alpha] sont présents, Cdx2 rétablit un fort niveau d'activité au promoteur FXR[alpha]3/[alpha]4 et non au promoteur FXR[alpha]1/[alpha]2. Pour conclure, ce projet de recherche montre bien que FXR dans un modèle mimant un contexte physiologique est capable d'activer des gènes cibles jusqu'ici inconnus et que l'expression des isoformes intestinaux est régulée de façon distincte par Cdx2 dans ce tissu.
30

Characterization of signal transduction pathways of alpha-1 adrenergic receptors in neonatal ventral hippocampus lesion rat model

Al-Khairi, Irina. January 2007 (has links)
Neonatal ventral hippocampus (nVH) lesioned animals show molecular and behavioral abnormalities analogous to those described in schizophrenia. As an extension to previous studies that showed an increase in ligand binding of cortical alpha-1 adrenergic receptors (AR) and a dysfunction in alpha-1 AR regulation of mesolimbic dopamine functions in post-pubertal nVH lesioned rats, we investigated the subcellular expression and activity of protein kinase C (PKC)---a second messenger in alpha-1 AR signaling---in the prefrontal cortex (PFC) and nucleus accumbens (NAcc) of post-pubertal nVH lesioned rats. Western blot analysis of membrane and cytosolic fractions showed complex changes in lesioned animals in the expression of different PKC subtypes following saline or alpha-1 AR agonist (cirazoline i.p.) injection. Among these changes, nVH lesioned animals showed a significant increase in membrane bound PKC alpha and phospho-PKC, and a decrease in cytosolic PKC gamma and PKC betaII in the PFC in comparison to sham-lesioned controls following saline. Cirazoline increased membrane bound PKC alpha in controls but decreased it in lesioned animals. In the NAcc, lesioned animals showed an increase in membrane bound and cytosolic PKC epsilon and PKC lambda levels following saline. Following cirazoline, lesioned animals showed a decrease in membrane bound PKC epsilon and PKC lambda, while controls showed an increase in cytosolic and membrane fractions of PKC epsilon with no change in PKC lambda. In vitro PKC activity assays showed increased basal activity in PFC slices of lesioned animals compared to controls, with no difference in NAcc slices. alpha-1 AR stimulation by the agonist phenylephrine (PE) increased PKC activity in PFC of controls while decreasing activity substantially in lesioned animals. In the NAcc, high concentrations of PE increased activity in controls, but decreased activity in lesioned animals. This abnormal expression and activity of PKC in the PFC and NAcc of nVH lesioned animals may be related to abnormal alpha-1 AR functions and may modulate some of the abnormal neuronal functions in these animals, such as working memory deficits and hyper neuronal excitability of the PFC and the NAcc.

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