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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.
241

"Efeitos renais da haploinsuficiência do gene Pkd1 (Polycystic kidney disease 1) em camundongos" / Renal effects of Pkd1 gene haploinsufficiency in mice

Sousa, Mauri Félix de 19 October 2005 (has links)
Vários estudos mostram que na doença renal policística autossômica dominante os cistos surgem a partir de um mecanismo de "dois-golpes". A patogênese das manifestações não-císticas, contudo, é pouco compreendida. Neste estudo usamos uma linhagem de camundongos endogâmica com uma mutação nula em Pkd1, onde animais heterozigotos apresentam formação cística renal mínima até 40 semanas de idade. O clearance de inulina e o número de glomérulos foram menores em machos Pkd1+/- que Pkd1+/+, enquanto o volume glomerular médio foi maior em heterozigotos. A excreção urinária de NO2/NO3 não diferiu significantemente entre os dois grupos. Avaliamos a osmolalidade urinária máxima em machos e fêmeas Pkd1+/- and Pkd1+/+, porém não foi detectada diferença significante entre os grupos heterozigoto e selvagem. Nossos resultados oferecem evidência direta de que a haploinsuficiência de Pkd1 resulta em anormalidades anatômicas e funcionais renais e sugerem que o estado haploinsuficiente de Pkd1 possa resultar na redução do número de néfrons por diminuir a ramificação tubular renal durante a nefrogênese / Several studies show that in autosomal dominant polycystic kidney disease cysts arise through a "two-hit" mechanism. The pathogenesis of non-cystic features, however, is poorly understood. In this study we used an inbred mouse line with a null mutation of Pkd1, where heterozygotes had minimal renal cyst formation up to 40 weeks of age. Inulin clearance and the number of glomeruli were lower in Pkd1+/- than in Pkd1+/+ males, while a higher average glomerular volume was observed in heterozygotes. The urinary excretion of NO2/NO3 did not significantly differ between the two groups. Maximal urinary osmolality was evaluated in Pkd1+/- and Pkd1+/+ males and females, but no significant difference was detected between the heterozygous and the wild type groups. Our results provide direct evidence that haploinsufficiency for Pkd1 results in anatomic and functional abnormalities of the kidney and suggest that Pkd1 haploinsufficiency may result in a reduced number of nephrons by diminishing renal tubule branching during nephrogenesis
242

Comprehensive phenotyping of two mouse mutants reveals a potential novel role of G protein-coupled receptor 30

Meoli, Luca 26 January 2011 (has links)
Publikationen die in letzter Zeit veröffentlicht wurden zeigten den G Protein-gekoppelte Rezeptor 30 (Gpr30) als neuer potenzieller Östrogen Rezeptor. Dieser Befund wird kontrovers diskutiert, zudem wurde die physiologische Funktion von Gpr30 bisher noch nicht vollständig geklärt. Ziel der vorliegenden Arbeit war die Erforschung der Rolle von Gpr30 in vivo. In einer primären und sekundären Untersuchung wurde eine phänotypische Charakterisierung einer Gpr30-defizienten Mauslinie vorgenommen. Diese Mauslinie wurde generiert, indem eine beta-Galactosidase-Neomycin Vektorkassette in den open reading frame des Gpr30 Gens eingesetzt wurde. Im Rahmen der primären Untersuchung zeigte die immunologische Analyse eine Reduzierung der T-Zellen sowohl bei den männlichen als auch bei den weiblichen mutanten Mäusen. In einer Thymus-Genexpressionanalyse konnten einige Gene identifiziert werden, die möglicherweise in der Regulation der Anzahl an T-Zellen involviert waren. Auf der Grundlage dieser Ergebnisse wurde eine Erhöhung der Kalzium-vermittelten T-Zellen Apoptose hypothetisiert. Gegenstand der sekundären Untersuchung war die Bestimmung eines möglichen metabolischen und kardiovaskulären Phänotyps, da Gpr30 überwiegend in den Blutgefäßen verschiedener Organe, sowie in der Pankreas und im Magen exprimiert ist. Zu diesem Zweck wurden die Mäuse einer Hochfettdiät unterzogen und es wurden metabolische sowie hemodynamische Tests durchgeführt. Um den Phänotyp dieser ersten Mauslinie zu bestätigen, wurde eine zweite Mauslinie ohne Selektionsmarker generiert. Insgesamt tragen die Ergebnisse der vorliegenden Studie zu einem besseren Verständnis der Funktion von Gpr30 in vivo bei. Eine Rolle des Rezeptors bezüglich der Regulation des Körpergewichts konnte widerlegt werden, während ein Einfluss auf den Lipid- und Muskelstoffwechsel angenommen werden kann. Zudem wurde gefunden, dass Gpr30 für einige Östrogen-regulierende, physiologische Prozesse nicht erforderlich ist. / Recent studies identified the G protein-coupled receptor 30 (Gpr30) as a potential new estrogen receptor. However, these findings remain still controversial and the physiological role of Gpr30 has not been clarified yet. In order to decipher the role of Gpr30 in vivo, we investigated the phenotype of a Gpr30 mutant mouse line, generated by the insertion of a beta-galactosidase-neomycin cassette into the Gpr30 open reading frame, in a primary and a secondary screen. The primary screen revealed a decrease of T cell levels in both male and female mutants. Thymus gene expression analysis allowed to detect some of the genes potentially involved in regulating T cell levels in these mice. On this basis a hypothesis of an increase in T cell calcium-mediated apoptosis was formulated. The secondary screen aimed at unraveling a potential metabolic and cardiovascular phenotype, being Gpr30 mainly expressed in the vasculature of several organs, as well as in the pancreas and in the chief gastric cells of the stomach. Therefore, mice were challenged with a defined high fat diet, and metabolic and hemodynamic tests were performed. To confirm the phenotype achieved in this first mouse line, a second one, devoid of any selection marker, was analyzed. Altogether the results achieved may contribute to a better understanding of Gpr30 function in vivo, disproving a role of Gpr30 in body weight regulation, suggesting a role in lipid and muscular metabolism, and providing evidence that Gpr30 may not be required for several estrogen-regulated physiological processes.
243

Aspectos moleculares da gênese e progressão de lesões periapicais induzidas experimentalmente em camundongos / Molecular aspects of genesis and progression of induced apical periodontitis in mice

Barreiros, Driely 18 July 2017 (has links)
O conhecimento dos eventos biológicos que ocorrem no periápice dos dentes com necrose pulpar se torna importante para compreender o desenvolvimento das lesões periapicais. Muitas são as moléculas e mediadores que participam na instalação da lesão periapical, a partir da infecção bacteriana que ocorre no interior dos canais radiculares. Assim, o objetivo do presente trabalho foi avaliar moléculas do sistema imune inato, da osteoclastogênese e metaloproteinases em lesões periapicais (LP) induzidas experimentalmente em camundongos knockout e wild type. Para esse objetivo, o presente estudo foi dividido em dois trabalhos distintos. O primeiro teve como objetivo avaliar a expressão de metaloproteinase 2 (MMP2) e metaloproteinase 9 (MMP9) durante a progressão da LP em camundongos knockout para TLR2 (TLR2 KO) e MyD88 (MyD88 KO), em comparação com camundongos wild type (WT). O segundo estudo avaliou a correlação da expressão gênica e imunomarcação de RANK, RANKL, OPG, TLR2 e MyD88 durante a progressão da LP em camundongos WT. No primeiro estudo lesões periapicais foram induzidas em molares inferiores de 54 camundongos TLR2 KO, MyD88 KO e WT (n=18/grupo). Após 7, 21 e 42 dias, os animais foram eutanaziados e as mandíbulas foram dissecadas e submetidas a processamento histotécnico. Os cortes histológicos foram submetidos a imunohistoquímica e posteriormente foi avaliada presença ou ausência de MMP2 e MMP9 nos diferentes grupos. No segundo estudo, 35 camundongos WT foram utilizados. As lesões periapicais foram induzidas nos primeiros molares inferiores de ambos os lados. Após 0 (G0), 7 (G7), 21 (G21) e 42 (G42) dias, os animais foram anestesiados e eutanasiados para que as mandíbulas fossem dissecadas e divididas ao meio.O lado direito das mandíbulas foi para o processamento histotécnico, para posterior marcação de RANK, RANKL, OPG, TLR2 e MyD88, por meio da imuno-histoquímica do lado esquerdo da mandíbula foi utilizado para a extração de RNA, para a determinação da expressão gênica de RANK (Tnfrsf11a), RANKL (Tnfrsf11), OPG (Tnfrsf11b), TLR2 (Tlr2) e MyD88 (Myd88) utilizando quantificação em Tempo Real da Reação da Polimerase em Cadeia (qRT-PCR). Para ambos os estudos, testes paramétricos e não paramétricos foram realizados com nível de significância de 5%. Foi possível observar, no primeiro estudo, que nos períodos iniciais da progressão da lesão periapical, houve um aumento na imunomarcação de MMP9 nos camundongos TLR2 KO e MyD88 KO, quando comparados aos WT, diferente da MMP2 que não se observou nenhum aumento na imunomarcação. No entanto, aos 42 dias observou-se uma redução da imunomarcação de MMP2 e um aumento da MMP9 nos camundongos TLR2 KO. Adicionalmente, no segundo estudo, foi possível observar um aumento da imunomarcação para RANK, RANKL, OPG, TLR2 e MyD88 durante a progressão da lesão periapical (p<0,05). O aumento da expressão de Tnfrsf11 foi diferente entre os grupos G0 e G42, e G21 e G42 (p=0,006). No entanto, a expressão de Tnfrsf11b foi diferente entre os grupos G0 e G7, G7, G21 e G42, sendo possível observar uma diminuição dessa expressão ao longo do tempo (p<0,001). Tlr2 foi mais expresso entre os grupos G0 e G42 (p=0,03). E a expressão da molécula Myd88 foi estatisticamente significante entre os grupos G0 e G7, G21 e G42 (p=0,01). A razão Tnfrsf11/Tnfrsf11b aumentou durante a progressão da lesão periapical (p=0,002). Também foi possível observar uma correlação moderada entre Myd88 e Rankl (r=0,42; p=0,03) e entre Myd88 e Tlr2 (r=0,48; p<0,0001). Após as metodologias empregadas e os dados analisados, concluímos que a produção de MMP2 e MMP9 foi modulada por TLR2 e Myd88 durante a progressão da lesão periapical. Alem disso, podemos sugerir que existe uma correlação positiva entre o sistema RANK/RANKL/OPG e as proteínas do sistema imune inato, TLR2 e MyD88, durante a perda óssea decorrente da infecção bacteriana dos canais radiculares e posterior progressão da lesão periapical. / Knowledge of the biological events occurring inteeth apex with pulp necrosis becomes important to understand the development of periapical lesions. There are manymolecules and mediators that participate in the installation of the periapical lesion, from the bacterial infection that occurs inside the root canals. Thus, the aim of the present study was to evaluate molecules of the innate immune system, osteoclastogenesis and metalloproteinases in experimentally apical periodontitis (AP) induced in knockout and wild type mice. For this purpose, the present study was divided into two distinct studies. The first one aimed to evaluate the expression of metalloproteinases 2 (MMP2) and metalloproteinases 9 (MMP9) during the progression of AP in TLR2 knockout mice (TLR2 KO) and MyD88 knockout mice (MyD88 KO), compared to wild type mice (WT). The second study evaluated the correlation of gene expression and immunostaining of RANK, RANKL, OPG, TLR2 and MyD88 during LP progression in WT mice. In the first study AP were induced in lower molars of 54 TLR2 KO, MyD88 KO and WT mice (n = 18 / group). After 7, 21 and 42 days, the animals were euthanized and the jaws were dissected and submitted to histotechnical processing. The histological sections were submitted to immunohistochemistry and subsequently the presence or absence of MMP2 and MMP9 in the different groups was evaluated. In the second study, 35 WT mice were used. Periapical lesions were induced in the lower first molars on both sides. After 0 (G0) to 7 (G7), 21 (G21) and 42 (G42) days, the animals were anesthetized and euthanized so that the jaws were dissected and divided in half. The right side of the jaws was for the histotechnic processing, for subsequent imunostaining of RANK, RANKL, OPG, TLR2 and MyD88, through immunohistochemistry and the left side of the jaws was used for the extraction of RNA, for the determination of expression of RANK (Tnfrsf11a), RANKL (Tnfrsf11), OPG (Tnfrsf11b), TLR2 (Tlr2) and MyD88 (Myd88) using Quantification Real Time of Polymerase Chain Reaction (qRT-PCR). For both studies, parametric and non-parametric tests were performed with significance level of 5%. It was possible to observe in the first study that in the initial periods of AP progression there was an increase in MMP9 immunostaining in TLR2 KO and MyD88 KO mice when compared to WT, different from MMP2 that no increase in immunostaining was observed. However, at 42 days there was a reduction in MMP2 immunostaining and an increase of MMP9 in TLR2 KO mice was observed. Additionally, in the second study, it was possible to observe an increase in the immunostaining for RANK, RANKL, OPG, TLR2 and MyD88 during periapical lesion progression (p <0.05). The increase in Tnfrsf11 expression was different between groups G0 and G42, and G21 and G42 (p = 0.006). However, the expression of Tnfrsf11b was different between the G0 and G7, G7, G21 and G42 groups, and a decrease in expression over time (p <0.001) was observed. Tlr2 was more expressed between the G0 and G42 groups (p = 0.03). And the expression of the Myd88 molecule was statistically significant between the G0 and G7, G21 and G42 groups (p = 0.01). The Tnfrsf11 / Tnfrsf11b ratio increased during the AP progression (p = 0.002). It was also possible to observe a moderate correlation between Myd88 and Rankl (r = 0.42, p = 0.03) and between Myd88 and Tlr2 (r = 0.48, p <0.0001). After the methodologies used and the data analyzed, we conclude that the production of MMP2 and MMP9 was modulated by TLR2 and Myd88 during the AP progression. In addition, we can suggest that there is a positive correlation between the RANK / RANKL / OPG system and the proteins of the innate immune system, TLR2 and MyD88, during bone loss due to bacterial infection of the root canals and subsequent progression of the apical periodontitis.
244

Evaluation of the coxsackievirus and adenovirus receptor (CAR) as a therapeutic target in cardiac disease

Chen, Chen 05 August 2009 (has links)
Der Coxsackievirus- und Adenovirusrezeptor (CAR) ist ein Typ I Transmembran-protein, das an der Adsorption von Viren und der Aufrechterhaltung von Zell-Zellkontakten beteiligt ist. Coxsackievirus B3 (CVB3) Infektionen sind eine häufige Ursache für akute Myokarditis, die bei Patienten häufig zu chronischer Kardiomyopathie bis zur Herzinsuffizienz führen können. CAR ist für die Aufnahme von Viren in unterschiedliche Zelltypen verantwortlich und damit ein potentielles Ziel bei der Therapie und Prävention von CVB3-Infektionen. Der komplette Knockout von CAR ist embryonal letal. Die betroffenen Embryonen zeigten Missbildungen des Herzens. Weiterhin konnte eine reduzierte Expression von Connexinen im Knockout beobachtet werden – ein mögliches Zeichen gestörter interzellulärer Kommunikation. In konditionellen CAR Knockout Tieren führte die Infektion mit CVB3 im Gegensatz zu CVB3-infizierten Wildtyp Kontrolltieren zu keinen pathologischen Veränderungen oder eine Erhöhung von Entzündungsmarkern. Die kontraktile Funktion des CVB3-infizierten Knockout Herzen war erhalten. Um mögliche unerwünschte Konsequenzen aus dem Verlust von CAR zu untersuchen, wurde eine umfassende kardiale Phänotypisierung durchgeführt, die AV-block im Knockout-Herzen zeigte. Der zugrunde liegende Mechanismus betrifft die Interaktion von Tight- und Gap-Junctions mit veränderter Expression und Lokalisierung von Connexinen, sowie die interzelluläre Kommunikation zwischen CAR-Knockout Kardiomyzeten. CAR ist essentiell für eine normale Embryonalentwicklung und kardiale Funktion. Das CAR-Knockout-Modell bietet einerseits den ersten genetischen Hinweis für eine Rolle von CAR als Virusrezeptor in vivo und belegt andererseits die Relevanz von direkter Virus-vermittelter Symptomatik gegenüber einer sekundären autoimmun- Komponente in CVB3-induzierten Herzerkrankungen. Damit ist CAR ein potentielles therapeutisches Target in der Prävention und Behandlung von viraler Myokarditis. / The coxsackievirus and adenovirus receptor (CAR) is a type I transmembrane protein involved in virus uptake and the maintenance of cell-cell contacts. Coxsackievirus B3 (CVB3) infections are frequent causes of human acute myocarditis, often resulting in chronic cardiomyopathy that may progress into terminal heart failure. The coxsackievirus and adenovirus receptor (CAR) is involved in virus uptake into various cell types and has therefore been suggested as a therapeutic target to prevent or treat CVB3 induced diseases. The complete CAR-knockout was embryonic lethal at midgestation with cardiac malformation. Connexin expression was decreased in the knockout, suggesting an abnormal cell-cell communication secondary to the loss of CAR. The role of CAR in murine viral myocarditis was investigated using the inducible CAR-knockout infected with CVB3. Unlike control animals exposed to CVB3, the cardiac inducible knockout mice did not exhibit structural changes such following CVB3 infection, or increased production of markers of inflammation, and severe contractile dysfunction. To evaluate possible adverse effects that might result from CAR deficiency, we implemented a detailed cardiac phenotyping protocol and found that CAR deficient animals developed AV nodal block. The underlying mechanism relates to the crosstalk of tight and gap junctions with altered expression and localization of connexins that affect the communication between CAR knockout cardiomyocytes. Thus, CAR is essential for embryonic development and normal cardiac function. The CAR-knockout does not only provide the first genetic evidence to establish CAR as the CVB3 receptor in vivo, but furthermore demonstrates the relevance of direct virus-mediated pathology versus a secondary autoimmune component in CVB3 induced heart disease. Our data suggest that CAR is a suitable target to help prevent and treat viral myocarditis.
245

Sistemas cannabinoide y purinérgico: posibles sustratos neurobiológicos de la drogadicción

Soria Rodríguez, Guadalupe 21 June 2006 (has links)
La adicción es un trastorno crónico de la conducta caracterizado por la búsqueda y el consumo compulsivos de la droga, la pérdida de control para limitar dicho consumo, a aparición de un estado emocional negativo cuando el acceso a la droga está impedido y la recaída en el proceso incluso tras largos períodos de abstinencia. El sistema dopaminérgico mesolímbico cortical ha sido propuesto como la principal base neurobiológica de la adicción, sin embargo existen otros sistemas de neurotransmision que participan en la consolidación del proceso adictivo.El sistema endocannabinoide, a traves del receptor CB1, participa en las propiedades adictivas de diferentes drogas de abuso como el delta9-tetrahidrocannabinol, la nicotina y la morfina. Sin embargo, hasta el momento de iniciar este trabajo, pocos estudios han demostrado una clara implicación del sistema endocannabinoide en las propiedades reforzantes de los psicoestimulantes. Mediante el uso de ratones CB1 knockout, hemos demostrado que el receptor CB1 participa en la eficacia reforzante de la cocaína. Además, la presencia de dicho receptor es necesaria para los procesos de consolidación de una conducta operante mantenida por la autoadministración de cocaína. Este estudio demuestra la importancia de dicho receptor CB1 en las propiedades adictivas de la cocaína, confirmando que el sistema endocannabinoide es un sustrato común para la adicción de drogas de abuso. Por otra parte, el sistema purinérgico modula numerosos sistemas de neurotransmisión en el SNC. La estrecha relación a nivel celular y funcional entre los receptores de adenosina y los receptores dopaminérgicos proporciona evidencias de que el sistema purinérgico podría modular los sistemas de recompensa. Utilizando diferentes modelos animales, hemos demostrado que los receptores de adenosina A2A son necesarios para que las propiedades adictivas de las drogas de abuso como los cannabinoides, los opioides, la nicotina y los psicoestimulantes se produzcan de un modo completo.Nuestros estudios nos permiten afirmar que ambos sistemas, el cannabinoide y el purinérgico podría suponer la existencia de nuevos sistemas de modulación común de los procesos adictivos. Asi, sería de gran interés desarrollar nuevas estrategias de bloqueo de los receptores A2A y CB1 para atenuar e incluso prevenir el desarrollo de la adicción. / Drug addiction is a chronically relapsing disorder that is defined by a compulsion to take the drug intake, a loss of control in limiting intake and a withdrawal-negative affect state when the access to the drug is interrupted. Mesolimbic dopaminergic system has been proposed as a fundamental neurobiological substrate for drug addiction. However, there is evidence for other neurotransmitter systems involved in the consolidation of the addictive process. The endocannabinoid system, through the activation of CB1 receptor, participates in the addictive properties of different drugs of abuse such as delta9-tetrahydrocannabinol, morphine and nicotine. Nevertheless, few studies have revealed an important implication of CB1 receptor in the reinforcing properties of psychostimulants. By using CB1 knockout mice, we have demonstrated that CB1 receptor participates in the reinforcing efficacy of cocaine. Moreover, this receptor is necessary for the consolidation processes involved in cocaine maintained intravenous self-administration. Therefore, this study reveals an essential role of CB1 receptor in cocaine addictive properties, confirming that the endocannabinoid system is a common substrate of addiction to drugs of abuse.On the other hand, the purinergic system modulates different neurotransmitter systems in the CNS. Adenosine receptors are closely related to dopaminergic receptors at both cellular and functional levels, suggesting that purinergic system could modulate the reward systems. By using different animal models, we have demonstrated that A2A adenosine receptors are necessary for the development of the addictive properties of drugs of abuse such as opioids, cannabinoids, nicotine and cocaine. Our studies suggest that both cannabinoid and purinergic systems could represent new and common modulatory systems of addictive processes. Thus, it would be of interest to develop new therapeutic targets blocking CB1 and A2A receptors to attenuate the development of addiction.
246

Kardiale Phänotypisierung einer transgenen Mauslinie mit herzspezifischer Calcium-Calmodulin-Kinase IIδc- Überexpression auf einem Phosphatase-Inhibitor-1- Knockout-Hintergrund / Cardiac phenotyping of a transgenic mouse model with cardiac specific Ca2+/calmodulin-dependent protein kinase IIδc overexpression on a phosphatase inhibitor -1 knockout background

Brammen, Christina Andrea Anna 29 September 2015 (has links)
No description available.
247

Charakterisierung der endosomalen Qb-SNAREs Vti1a und Vti1b / Characterization of the endosomal Qb-SNAREs Vti1a and Vti1b

Kreykenbohm, Vera 03 November 2004 (has links)
No description available.
248

Funtional Analysis of the Murine Genes, MOCS1 and Sox15 / Analysis of the Murine Genes, MOCS1 and Sox15 / Funktionelle Analyse der Mousgene MOCS1 und Sox15 / Analyse der Mausgene MOCS1 und Sox15

Lee, Heon-Jin 02 July 2003 (has links)
No description available.
249

Zur Funktion des Brunol4-Gens / Analysis on the function of the brunol4 gene

Ellen, Heike Lucia 24 July 2012 (has links)
No description available.
250

Expression and functional analysis of murine Brunol1 and Brunol4, members of Elav/Bruno family / Expression and functional analysis of Brunol1 and Brunol4 / Expressions- und Funktionsanalysen von murinem Brunol1 und Brunol4, Mitgliedern der elav/Bruno Familie / Expressions- und Funktionsanalysen von murinem Brunol1 und Brunol4

Dev, Arvind 01 November 2006 (has links)
No description available.

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