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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.
171

Differentielle Expression von HLA-DRB-Genen

Heldt, Christian 31 July 2002 (has links)
In den humanen Leukozyten-Antigenen (HLA) wird die wichtigste genetische Ursache von rheumatoider Arthritis gesehen. Es wurden bisher mehrere Mechanismen beschrieben, wie diese HLA-Moleküle die Entstehung und den Verlauf der Erkrankung beeinflussen. Im Rahmen dieser Arbeit wurde die differentielle Expression von HLA-DRB-Genen in unterschiedlichen Antigen-präsentierenden Zellen als möglicher Mechanismus untersucht. Dabei wurden strukturelle Unterschiede zwischen den Promotoren des krankheitsassoziierten HLA-DR4-Haplotyps und den neutralen Haplotypen DR7 und DR9 eingehender betrachtet. Allen drei Haplotypen ist gemein, daß sie das DRB4-Gen als zweites funktionelles DRB-Gen tragen, wobei das DRB4-Gen entweder den DRB4A oder den -B-Promotor besitzt. Um den Einfluß einzelner Promotorelemente auf die mit dem Luziferase-Assay bestimmten Transkriptionsaktivitäten näher zu untersuchen, wurde mit Hilfe der surface plasmon resonance die Bindung der Transkriptionsfaktoren aus den Zellkernlysaten von der humanen Monozytenzellinie THP-1 und von der humanen B-Lymphom-Zellinie BJAB an die unterschiedlichen S-, X-, Y-, CCAAT- und TATA-Boxen analysiert. Es konnte gezeigt werden, daß die unterschiedliche Expression von DRB4A und DRB4B durch die ubiquitäre TATA-Box vermittelt wird. Dagegen wurde die INF-gamma-Stimulation der HLA-DR-Expression von THP-1- aber auch von BJAB-Zellen durch die für die HLA-DR-Promotoren spezifische X-Box vermittelt. Bei der Analyse von DR4-, DR7- und DR9-positiven Patienten einer bereits gut charakterisierten RA-Kohorte stellte sich heraus, daß der DRB4B-Promotor, welcher im Vergleich zu DRB4A eine höhere transkriptionelle Aktivität besitzt, mit einem schweren Krankheitsverlauf assoziiert ist, so daß eine erhöhte HLA-DR-Expression den Krankheitsverlauf negativ zu beeinflussen scheint. / Disease associated human leukocyte antigen (HLA) genes have been identified in humans where they are assumed to promote the susceptibility and/or progression of rheumatoid arthritis. Several mechanisms have been described how these HLA haplotypes impact on the disease. Among them the differential expression of HLA-DRB molecules in different types of antigen-presenting cells, which was investigated here in detail. The promoters of the disease associated HLA-DR4 to the neutral DR7 and DR9 haplotypes were analyzed for sequence polymorphisms resulting in functional differences. All three haplotypes carry as a second functional DRB gene the DRB4 gene, which is regulated by the DRB4A or -B promoter. To determine the impact of the promoter elements on the transcriptional activities measured by luciferase assay the surface plasmon resonance technology was employed. To this end, nuclear extracts from the monocytic cell line THP-1 and from the B lymphoma cell line BJAB were used to analyze their binding to the various S-, X-, Y-, CCAAT-, and TATA boxes. It could be demonstrated that the differential expression of DRB4A and -B was regulated via the ubiquitous TATA box. By contrast, the INF-gamma stimulation of HLA expression in THP-1 and BJAB was mediated via the unique X box. Analyzing the DR4, DR7 and DR9 positive patients of an RA cohort, the DRB4B promoter, which has a higher transcriptional activity than the DRB4A promoter, is associated with radiographic progression of RA. This data is thus indicative of an impact of elevated HLA-DR expression on the progression of the disease.
172

Tierexperimentelle Untersuchung des Einflusses von N-Acetylcystein in Kombination mit Tirilazad Mesylat auf die mesenteriale Plasmaextravasation und Leukozytenadhärenz bei Endotoxinämie

Müller, Julia 17 January 2007 (has links)
Störungen im Bereich der Mikrozirkulation gelten als ursächlich für die Entstehung des Multiorganversagens bei Sepsis, wobei der Darm eine zentrale Rolle einnimmt. Aktivierte Leukozyten setzen u.a. Sauerstoffradikale frei, die entscheidend zur Zerstörung der endothelialen Integrität beitragen. Die Antagonisierung schädigender Mediatoren stellt ein Prinzip der adjunktiven Sepsis-Therapie dar, wobei die antioxidativ wirkenden Substanzen N-Acetylcystein (NAC) und Tirilazad Mesylat (TM) in mehreren Studien positive Effekte gezeigt haben. In einer tierexperimentellen Untersuchung an Ratten wurde der Effekt der kombinierten Gabe von NAC und TM auf die mesenteriale Mikrozirkulation, auf die Freisetzung von TNF-alpha, IL-1beta, IL-6, IL-10 und auf die Leukozytenzahl unter einer kontinuierlichen Lipopolysaccharidbelastung (LPS) von 10 mg/kg KG untersucht. Die Beurteilung der mesenterialen Mikrozirkulation erfolgte mittels Intravitalmikroskopie. Hierbei wurde das Ausmaß der Leukozytenadhärenz am Endothel der mesenterialen Venolen als Maß für die Leukozytenaktivierung und die Plasmaextravasation als Parameter für die Endotheldysfunktion bestimmt. Dabei konnte während zwei Stunden Endotoxinämie die Zunahme der Plasmaextravasation an mesenterialen Venolen durch die kombinierte Gabe von NAC und TM nicht signifikant beeinflusst werden (p>0,05). Eine tendenziell erhöhte Plasmaextravasation unterstützt die Hypothese, dass leukozytenunabhängige Mechanismen für die Plasmaextravasation existieren. Während zwei Stunden Endotoxinämie kam es zu einer signifikanten Reduktion der Anzahl der fest adhärenten Leukozyten in der NAC/TM-Gruppe im Vergleich zur LPS-Gruppe (p=0,001). Durch die kombinierte Gabe von NAC und TM konnte die endotoxininduzierte Freisetzung von TNF-alpha, IL-1beta, IL-6, IL-10 und die endotoxinbedingte Leukopenie nicht signifikant beeinflusst werden. / Disturbances of the microcirculation are causal for the pathophysiology of multiorgan failure related to sepsis in which the gut plays a central part. Activated leukocytes release i.e. oxygen radicals which decisively contribute to the destruction of the endothelial integration. To antagonize the damaging mediators is a principle of the adjunctive sepsis therapy in which the antioxidant agents N-acetylcysteine (NAC) and tirilazad mesylate (TM) showed positive effects in several studies. The effect of the combined administering of NAC and TM under continuous lipopolysaccharide (LPS) exposure of 10 mg/kg BW on the mesenteric microcirculation, on the release of TNF-alpha, IL-1beta, IL-6, IL-10 and on the number of leukocytes was examined in an animal study on rats. The appraisal of the microcirculation was done by intravital microscopy. The degree of leukocyte adherence on the endothelium of mesenteric venules was determined for the degree of leukocyte activation, and the plasma extravasation was the parameter for the endothelial dysfunction. The increase of plasma extravasation on mesenteric venules during 2 hours of endotoxemia could not be affected significantly by the combined administering of NAC and TM. The tendency of increased plasma extravasation supports the hypothesis of the existence of a leukocyte independent mechanism of plasma extravasation. During 2 hours of endotoxemia the NAC/TM group showed a significant decrease in the number of firmly adherent leukocytes in comparison to the LPS group. There was no significant effect on the endotoxin induced release of TNF-alpha, IL-1beta, IL-6, IL-10 and the endotoxin induced leukopenia by the combined administration of NAC and TM.
173

Effekte von Hyperoxie und Stickstoffmonoxid beim Neugeborenen

Höhn, Thomas 01 October 2002 (has links)
In der vorliegenden Arbeit sind Untersuchungen vorgestellt, die sich mit Wirkungen und Interaktionen von zwei ubiquitär im menschlichen Körper vorkommenden Gasen befassen, i.e. Sauerstoff und Stickstoffmonoxid. Im Falle beider Substanzen ermöglicht die geringe Größe der Moleküle eine freie Diffusion über Membranen hinweg, eine Eigenschaft, die für die Funktion der Signaltransduktion geradezu prädestiniert. Aus den vorgelegten Untersuchungen lassen sich die folgenden Folgerungen ableiten: * Stickstoffmonoxid wirkt in-vitro selektiv bakteriostatisch auf Bakterien, die üblicherweise Früh- und Neugeborene besiedeln. Dabei hängt die Selektivität von den jeweiligen bakteriellen Verteidigungsmechanismen ab, die bakteriostatische Wirkung liegt in einem Konzentrationsbereich, der außerhalb desjenigen liegt, der derzeit klinisch angewendet wird. * Hyperoxie führt im Ganztiermodell der unreifen Ratte zu einer zerebralen Hochregulation von iNOS und damit zur Synthese von NO. Soweit dies anhand der Synthese von Peroxynitrit als definitivem Schädigungsmechanismus beurteilbar ist, wird trotz entsprechender iNOS-Expression wenig bis gar kein Peroxynitrit gebildet. Da das Zusammentreffen von NO und Sauerstoff sonst regelhaft zur Entstehung von Peroxynitrit führt, müssen im Gehirn der unreifen Ratte ausreichende antioxidative Schutzmechanismen präsent sein, die diese Reaktion verhindern. * Im in-vitro-Modell der Gasäquilibrierung von Nabelschnur-PMN zeigte sich unter Hyperoxie das ausgeprägteste Aktivierungsmuster aller verglichenen Sauerstoffkonzentrationen. Dies stand im Gegensatz zur Exposition adulter Zellen, hier fand sich eine größere Hyperoxietoleranz bei gleichzeitig stärkster Aktivierung unter Hypoxiebedingungen. Welche Bedeutung diesen Ergebnissen im klinischen Umgang mit Neugeborenen zukommt muß derzeit noch offen bleiben. Allerdings häufen sich Hinweise aus experimentellen Studien, die darauf hindeuten, daß ein restriktiver Umgang mit hohen Sauerstoffkonzentrationen auch im klinischen Umfeld gerechtfertigt sein könnte. / The present investigations deal with the effects and interactions of gases, which are ubiquitous in the human body i.e. oxygen and nitric oxide. Both substances are small enough to freely diffuse across biological membranes. This ability predestines both molecules for the function of signal transduction. The results of our investigations lead to conclusions as follows: * Nitric oxide has selective bacteriostatic effects in-vitro on some bacterial strains typically isolated from preterm and term newborn infants. Selectivity depends on the presence of bacterial defense mechanisms. The bacteriostatic effect takes place at concentrations above those currently used in clinical practice. * Hyperoxia leads to upregulation of iNOS and subsequent NO production in an animal model of the immature rat. Despite this upregulation of iNOS synthesis there is no increased production of peroxynitrite which is known to cause cellular and DNA damage. Since the combination of NO and high concentrations of oxygen lead to peroxynitrite formation on a regular basis, effective antioxidant mechanisms appear to prevent peroxynitrite formation in the brain of the immature rat. * The most pronounced activation of cord blood polymorphonuclear cells (PMN) during conditions of hyperoxia, normoxia, and hypoxia was found for exposure towards high oxygen concentrations in an in-vitro model of gas equilibration. As opposed to that, hypoxia was the most potent trigger for adult PMN. It remains to be determined which clinical implications must be derived from these results. However, increasing experimental evidence indicates that exposure towards high oxygen concentrations should be restricted also in clinical practice and not only in preterm infants, but also in term newborns.
174

Experimentelle Melanin-induzierte Uveitis

Puchta, Joachim 23 January 2002 (has links)
Experimentelle Melanin-induzierte Uveitis (EMIU): Modulation der Leukozyten-Endothelzell-Interaktion durch Makrophagendepletion - intravitalmikroskopische Analysen. Einleitung: Die Experimentelle Melanininduzierte Uveitis (EMIU) dient als Modell für eine autoimmune Iridozyklitis und Choroiditis. Die frühe Entzündungsreaktion ist durch eine gesteigerte Leukozyten-Endothel-Interaktion gekennzeichnet. Um die Rolle von Makrophagen bei der Induktion der EMIU zu untersuchen, analysierten wir Veränderungen der Leukozyten-Endothel-Interaktionen in Irisvenolen anästhesierter Ratten nach Makrophagendepletion mit liposomalem Clodronat. Methoden: Die EMIU wurde durch intraperitoneale Injektion einer Emulsion aus 250 µg bovinen Melanosomen in komplettem Freund Adjuvant und Pertussistoxin bei Lewis Ratten induziert. Die Tiere wurden mit 2 ml Clodronat-Liposomen (Clodronat-lip) an den Tagen 2; 1; 4; 6 beziehungsweise 8 nach Immunisierung behandelt. Kontrolltiere erhielten anstelle von Clodronat-lip Leerliposomen (Kontrolle). Für die Intravitalfluoreszenzmikroskopie wurden Leukozyten intravasal mit Rhodamin 6G gefärbt. Anschließend wurden die postkapillären Irisvenolen am 4.; 6.; 8. und 10. Tag untersucht, um die Zahl der rollenden und fest am Endothel adhärenten Leukozyten zu quantifizieren. Weitere Parameter wie Zellzahl und Proteingehalt des Kammerwassers, TNF-alpha und IFN-gamma im Plasma und das Differentialblutbild wurden zur Charakterisierung der Entzündungsreaktion herangezogen. Ergebnisse: Bei makrophagendepletierten Tieren konnten spaltlampenmikroskopisch keine entzündlichen Veränderungen des Vorderabschnittes beobachtet werden. Der prozentuale Anteil rollender Leukozyten war am 8. Tag mit 2 +/- 1.1 vs. 15.2 +/- 1.6; 5.2 +/- 0.5% (Clodronat-lip vs. EMIU; Kontrolle, Mittelwert +/- MSF, ANOVA, p
175

Interação leucócito-endotélio induzida pelo veneno de Bothrops jararaca>: papel de proteases, mediação farmacológica e soroneutralização / Leukocyte-endothelium interaction induced by Bothrops jararaca venom: role of proteases, pharmacological mediation and serum neutralization

Zychar, Bianca Cestari 24 January 2008 (has links)
Toxinas classificadas como serinoproteases, metaloproteases e fosfolipases A2, isoladas de venenos botrópicos, podem induzir reações inflamatórias que contribuem na gravidade dos sintomas locais observados nestes envenenamentos. Entretanto, a contribuição efetiva de cada uma destas toxinas no efeito inflamatório induzido pelo veneno não é bem compreendida. Neste estudo, o veneno de Bothrops jararaca (VBj) foi tratado com Fluoreto de fenil-metil-sulfonila (PMSF), 1,10- fenantrolina (OF) ou Brometo de p-bromafenacila (p-BPB) para inibição destas enzimas. Observou-se parâmetros de leucócitos em rolling, aderidos e migrados na interação leucócito-endotélio, após a injeção de 1g dos veneno tratados no subcutâneo da bolsa escrotal de camundongos. Os resultados foram comparados aos obtidos com o veneno bruto, sem tratamento. Os animais injetados com VBj bruto apresentaram um aumento marcante de adesão celular em todos os tempos estudados, sendo o pico dessa interação entre a 2ª e 4ª hora após a injeção. Os grupos injetados com VBj também apresentaram o maior número de células migradas na 4ª h, permanecendo esse número alto na 24ª hora e diminuindo significativamente na 48ªh após a injeção do VBj. Baseando-se nesta cinética, todos os outros estudos foram verificados na 2ª e 24ª hora. Os resultados mostraram que o tratamento do VBj com OF resultou diferenças significantes nas alterações da interação leucócito-endotélio. Nos venenos tratados para inibição de serinoproteases e FLA2 verificou-se que o tratamento não resultou em diferenças nos parâmetros de interação leucócito-endotélio, quando comparados ao grupo injetado com o veneno bruto, nos dois tempos estudados. Tratamentos farmacológicos indicam que os eicosanóides originados da via da ciclooxigenase, TNF- e NO participam da mediação da interação leucócito endotélio induzidos pelo VBj. Mas aparentemente não os eicosanóides originados pela via das lipoxigenase, histamina ou serotonina,. O efeito do soro antibotrópico (SAB) na interação leucócito-endotélio induzido por VBj também foi avaliado. O SAB induziu, per se, uma interação leucócito-endotélio semelhante ao observado em animais injetados com VBj, efeito este aparentemente devido ao fenol utilizado como conservante no antiveneno. Utilizando-se um soro antibotrópico sem fenol, estas reações não foram observadas e verificou-se que o soro sem fenol evita as alterações na interação leucócito-endotélio induzidas pelo VBj. Em conclusão, conjuntamente nossos dados indicam que: 1) as metaloproteases tem maior importância, e que as fosfolipases e serinoproteases tem um papel secundário nas alterações na interação leucócito-endotélio induzida pelo VBj; 2) que os eicosanóides são os principais mediadores nestes parâmetros inflamatórios e 3) que o SAB possui anticorpos contra as toxinas do veneno que induzem alterações na interação, mas o fenol presente no soro é responsável pelas reações pró-inflamatórios indesejadas. Finalmente, os resultados sugerem que a associação de antiinflamatórios à soroterapia para o tratamento das reações inflamatórias locais induzidas pelo VBj deve ser considerada e estudada mais aprofundadamente. / Toxins classified as serineproteases, metalloproteases or phospholipases A2, isolated from venoms of Bothrops snakes can induce inflammatory reactions that contribute to the severity of local symptoms observed in envenomation. Nevertheless, the real contribution of each one of these classes of toxins to the inflammatory effect of whole venom is poorly understood. In this study, Bothrops jararaca venom (BjV) was treated with phenyl-methyl-sulfonyl-fluoride (PMSF), 1,10-phenantroline (sPhe) or p-bromophenacyl bromide (pBPB), to inhibit those classes of enzymes. Inflammatory parameters of leukocyte-endothelial interaction (LEI), namely leukocytes rolling, adhesion or migration, observed after injecting of 1mg of treated venoms into the subcutaneous tissue of the scrotal bag of mice, were evaluated and compared to those observed after the injection of non-treated venom. Animals injected with BjV presented an a marked expressive increase in cellular adhesion in all periods of time studied, but peaking between 2 and 4h after BjV injection. The venom-injected groups also presented the highest number of migrated cells hour 4, wich remained up to hour 24, and decreasing significantly 48h after the BjV injection. Based on this kinetics, all other studied were performed evaluating LEI parameters on 2nd and 24th hour after venom injection. Results showed that sPhe -treated venom presented significant differences in LEI. LEI parameters induced by pBPB- and PMSF-treated venom were similar to those observed with non-treated venom. Pharmacological treatments indicate that eicosanoids from the cyclooxygenase pathway, TNF- and NO participate on the mediation of the alterations of leukocyte-endothelium interaction induced by venom. Eicosanoids from the lipoxygenase pathway, histamine and serotonin apparently do not mediate these alterations. The effect of the Bothrops antivenom in blocking the disturbances of leukocyte-endothelial interaction induced by BjV was also evaluated. Surprisingly, the antivenom per se induced alterations in LEI similar to those induced by the venom. Conversely, a phenol-free antivenom did not induce LEI alterations and avoid those induced by the BjV. In conclusion, our findings indicated that: 1) the major importance of metalloproteases, and a secondary role for phospholipases and serineproteases in alterations of leukocyte-endothelial interactions induced by Bothrops jararaca venom; 2) eicosanoids are the main mediators of these alterations; 3) the Bothrops antivenom has antibodies against toxins that induce LEI alteration, but the phenol used in antivenom as a preservative can cause some undesired pro-inflammatory reactions. Finally, present results indicate that the use of anti-inflammatory drugs associated with serum therapy for the treatment of local inflammatory reactions induced by Bothrops snake venoms should be considered and further studied.
176

Estudo dos efeitos da solução salina hipertônica nas alterações microcirculatórias e no desenvolvimento do processo inflamatório em modelo de morte encefálica em ratos / Study of hypertonic saline solution effects on microcirculatory alterations and development of the inflammatory process in a rat brain death model

Correia, Cristiano de Jesus 06 February 2018 (has links)
INTRODUÇÂO: A morte encefálica (ME) induz instabilidade hemodinâmica com hipoperfusão microcirculatória, desencadeando inflamação e disfunção de órgãos. OBJETIVO: Este estudo teve como objetivo investigar os efeitos da solução salina hipertônica (SH) 7,5% na evolução da resposta inflamatória no tecido mesentérico de ratos submetidos à ME. MÉTODOS: Ratos Wistar machos foram anestesiados e ventilados mecanicamente. A ME foi induzida pela insuflação rápida de um balão posicionado na cavidade intracraniana (Fogart 4F). Os ratos foram divididos aleatoriamente em: 1) Falso-operado, ratos submetidos aos procedimentos cirúrgicos e trepanação (FO, n=17); 2) Controle, ratos tratados com solução salina isotônica (NaCl 0,9%, 4 mL/kg) imediatamente após ME (CO, n=17); 3) Solução hipertônica 1, ratos tratados com solução hipertônica (NaCl 7,5%, 4 mL/kg) imediatamente após ME (SH1, n=17); 4) Solução hipertônica 60, ratos tratados com solução hipertônica 60 min após ME (SH60, n=17). Três horas após a indução da ME ou o término do procedimento cirúrgico para os animais do grupo FO, foram coletados os seguintes dados: (a) perfusão mesentérica, fluxo sanguíneo e interações leucócito-endotélio no mesentério, pela técnica de microscopia intravital; (b) expressão de proteínas de óxido nítrico sintase endotelial (eNOS), endotelina-1, P-selectina e molécula de adesão intercelular (ICAM)-1, por imunohistoquímica; (c) expressão gênica de eNOS e endotelina-1, por reação em cadeia da polimerase em tempo real (PCR); (d) concentrações séricas de citocinas, quimiocinas e corticosterona por meio de enzimaimunoensaio (ELISA). RESULTADOS: Todos os grupos submetidos a ME apresentaram um comportamento semelhante da pressão arterial, sendo observado um pico hipertensivo, seguido de período de hipotensão, logo após a insuflação do cateter intra-craniano. A proporção de pequenos vasos perfundidos foi diminuída no grupo CO (46%) em comparação com FO (74%, p=0,0039). A SH foi capaz de restaurar a proporção de vasos perfundidos (SH1=71%, p=0,0018). Não houve diferenças no fluxo sanguíneo mesentérico entre os grupos. A expressão proteica de eNOS aumentou significativamente em ratos com SH (SH1 e SH60, p=0,0002) em comparação ao grupo CO. Resultados semelhantes foram observados em relação à endotelina-1 (p < 0,0001). Não houve diferenças na expressão gênica de eNOS e endotelina-1. O aumento no número de leucócitos \"rollers\" (p=0,0015) e migrados (p=0,0063) foi observado no grupo CO em comparação com FO. Ratos com SH demonstraram redução significativa em todos os parâmetros da interação leucócito-endotélio. Com relação às moléculas de adesão, a expressão de ICAM-1 estava elevada no grupo CO em comparação com o FO, enquanto que o tratamento com SH diminuiu a expressão de ICAM-1 (SH1 e SH60, p=0,0002). CONCLUSÕES: O emprego da solução salina hipertônica melhorou a perfusão mesentérica, influenciou positivamente o metabolismo do óxido nítrico e reduziu a inflamação no mesentério, com diminuição da adesão e migração leucocitária, em ratos submetidos a ME / BACKGROUND: Brain death (BD) induces hemodynamic instability with microcirculatory hypoperfusion leading to increased organ inflammation and dysfunction. OBJETIVE: To investigate the effects of 7.5% hypertonic saline solution (HS) on the course of the inflammatory response in rats submitted to BD. METHODS: Male Wistar rats were anesthetized and mechanically ventilated. BD was induced by rapid inflation of intracranial balloon catheter (Fogart 4F). Rats were randomly divided in: 1) Sham-operated, rats submitted only to trepanation (SH, n=17); 2) Control, rats treated with normal saline solution (NaCl 0.9%, 4 mL/kg) immediately after BD (CO, n=17); 3) Hypertonic solution 1, rats treated with hypertonic solution (NaCl 7.5%, 4 mL/kg) immediately after BD (HS1, n=17); 4) Hypertonic solution 60, rats treated with hypertonic solution 60 min after BD (HS60, n=17). Hundred eighty minutes thereafter the following experiments were performed: (a) mesenteric perfusion, blood flow, and leukocyte-endothelial interactions, by intravital microscopy; (b) protein expression of endothelial nitric oxide synthase (eNOS), endothelin-1, P-selectin, and intercellular cell adhesion molecule (ICAM)-1, by immunohistochemistry; (c) gene expression of eNOS, and endothelin-1, by real-time polymerase chain reaction (PCR); (d) serum concentrations of cytokines, chemokines and corticosterone by enzyme-linked immunosorbent assay (ELISA). RESULTS: All BD groups presented similar hypertensive peak followed by hypotension. The proportion of perfused small vessels was decreased in CO group (46%) compared to SH (74%, p=0.0039). HS was able to restore the proportion of perfused vessels (HS1=71%, p=0.0018). There were no differences in mesenteric blood flow between groups. eNOS protein expression significantly increased in rats given HS (HS1, and HS60, p=0.0002). Similar results were observed regarding endothelin-1 (p < 0.0001). There were no differences in eNOS and endothelin-1 gene expression. Increased numbers of rolling (p=0.0015) and migrated (p=0.0063) leukocytes were observed in CO group compared to SH. Rats given HS demonstrated an overall reduction in leukocyte-endothelial interactions. Levels of ICAM-1 increased in CO group compared to SH, and decreased in HS-treated groups (p=0.0002). CONCLUSIONS: Hypertonic saline improves mesenteric perfusion, increased eNOS and endothelin-1 protein expression, and reduced inflammation by decreasing leukocyte adhesion and migration in BD rats
177

A proteína de transferência de colesterol esterificado humana protege camundongos da sepse polimicrobiana e atenua a resposta inflamatória em macrófagos estimulados com lipopolissacarídeo / The human cholesteryl ester transfer protein protects mice from polymicrobial sepsis and attenuates the inflammatory response in macrophages stimulated with lipopolysaccharide

Venancio, Tatiana Martins 09 February 2015 (has links)
Sepse é a resposta inflamatória sistêmica decorrente de infecção grave, com alto índice de mortalidade, tornando-se um grave problema de saúde pública. Apesar dos inúmeros estudos realizados em busca de alternativas terapêuticas, o entendimento acerca dos mecanismos envolvidos na doença permanece restrito. A interação entre o metabolismo lipídico e a resposta inflamatória tem sido intensamente investigada. Neste estudo, avaliou-se a influência da proteína de transferência de colesterol esterificado (CETP) - glicoproteína plasmática que promove a transferência de lípides entre lipoproteínas - na resposta inflamatória. Inicialmente, foram comparados camundongos transgênicos para CETP humana (CETP) e controles irmãos não transgênicos (WT) submetidos ao modelo de sepse polimicrobiana de ligadura e perfuração do ceco (CLP), avaliando a taxa de sobrevida e o perfil inflamatório entre os grupos. Em seguida, a resposta inflamatória em macrófagos de peritônio de camundongos estimulados com LPS na ausência ou presença da CETP exógena (CETP humana recombinante) e endógena (macrófagos de animais CETP) foi analisada. Verificou-se que camundongos CETP apresentaram maior taxa de sobrevida, maior migração de linfócitos para o foco infeccioso, menores concentrações plasmáticas de IL-6 e menor expressão proteica do receptor Toll-like 4 (TLR4) e da enzima aciloxiacilo hidrolase (AOAH) no fígado, comparados aos WT. Nos macrófagos, observou-se que a presença da CETP recombinante foi capaz de se ligar ao LPS, pela análise da microscopia confocal, e, em cultura, reduziu de forma dose dependente a captação de LPS, a expressão de TLR4, a ativação do NF-kB (p65) e a secreção de IL-6 para o sobrenadante do cultivo celular. Os dados obtidos com os macrófagos de animais CETP corroboraram, em parte, os encontrados com a utilização da CETP exógena. Houve redução da captação de LPS e da ativação do NF-kB (p65), sem alteração na expressão de TLR4 e secreção de IL-6. Entretanto, apresentaram redução das concentrações de TNF-alfa celular e no sobrenadante de cultura. Dessa maneira, foi possível concluir que a CETP atua como agente modulador da resposta inflamatória induzida pela CLP e em macrófagos estimulados pelo LPS. Esses achados devem ser considerados nas doenças inflamatórias e nos futuros estudos relacionados à inibição da CETP, além de estabelecer novas perspectivas de tratamento da sepse / Sepsis is a systemic inflammatory response due to serious infection with high mortality rate, which has become a serious problem for public health. Despite numerous studies seeking for therapeutic alternatives, the understanding of the mechanisms involved in this disease remains limited. The interaction between lipid metabolism and inflammatory response has been intensively investigated. In the present study it was evaluated the influence of CETP (cholesteryl ester transfer protein) - plasma glycoprotein that promotes the transfer of lipids between lipoprotein - in the inflammatory response. Initially transgenic mice for human CETP (CETP) were compared to non transgenic control mice (WT) after polymicrobial sepsis induced by cecal ligation and puncture (CLP), to determine survival rate and the inflammatory profile between groups. Then, macrophages isolated from peritoneal cavity stimulated with LPS in the presence or absence of exogenous CETP (recombinant human CETP) and endogenous CETP (macrophages from CETP mice) were analyzed. It was found that CETP mice showed a higher survival rate, a greater lymphocyte migration to infectious focus, a lower IL-6 plasma concentration and a decrease in Toll-like receptor 4 (TLR4) and acyloxyacyl hydrolase enzyme (AOAH) protein expression in the liver in comparison to WT mice. In macrophages, recombinant CETP was able to bind to LPS, by confocal microscopy analysis and in cell culture, it was observed that in the presence of the recombinant CETP macrophages presented decreased in LPS uptake, TLR4 expression, NF-kB activation (p65) and IL-6 secretion into the cell culture medium. Furthermore, the results with macrophages from animals CETP corroborate partly with what was found in the exogenous experiments. LPS uptake and NF-kB activation (p65) were reduced, but no difference regarding the expression of TLR4, nor the IL-6 secretion to the cell culture medium. However, the CETP group also showed reduced levels of TNF-alfa both in macrophages and in the culture supernatant. Thus, we conclude that CETP acts as modulator of the inflammatory response induced by CLP and in the macrophages stimulated by LPS. In addition, new therapeutic perspectives could be established
178

Efeito do inibidor de proteinase de origem vegetal EcTI, sobre a lesão pulmonar induzida pela elastase em camundongos C57BI6 / Effects of proteinase inhibitor from plant EcTI on elastase-induced lung alterations in mice

Theodoro Junior, Osmar Aparecido 02 June 2014 (has links)
Introdução: As proteinases tem um papel importante no desenvolvimento, na destruição tecidual e na produção de muco causada pela DPOC. O inibidor de proteinase de origem vegetal Enterolobium contortisiliquum Tripsin Inhibitor (EcTI) inibe tanto as proteinases da classe serina quanto da classe cisteína. Objetivos: Avaliar os efeitos do tratamento com EcTI nas alterações pulmonares induzidas pela elastase em camundongos. Métodos: Camundongos C57Bl6 receberam elastase via intratraqueal (50 uL/animal, grupo ELA) ou salina (grupo SAL). Os camundongos foram tratados com EcTI (2mg/kg) nos dias 1, 15 e 21 após a instilação de elastase (grupo ELA-EcTI) ou salina (grupo SAL-EcTI). No dia 28 do protocolo, os animais foram anestesiados, a mecânica pulmonar foi medida e o óxido nítrico exalado coletado. Posteriormente, foi realizado o lavado broncoalveolar e os pulmões foram removidos para a preparação de lâminas de histoquímica e imunohistoquímica. Por meio de morfometria analisamos o número de células positivas para neutrófilos, TNF-alfa, MMP-9, MMP-12, TIMP-1, iNOS, eNOS assim como a fração de volume de 8-iso-PGF2alfa, fibras colágenas e elásticas, nos septos alveolares e nas vias aéreas. Também foram avaliados o número de células positivas para macrófagos nos septos alveolares e MUC5ac nas vias aéreas. Resultados: O inibidor de proteinase EcTI reduziu as alterações de mecânica pulmonar (Ers, Htis e Raw), destruição do septo alveolar (Lm) e o número de células no lavado broncoalveolar (células totais, macrófagos, neutrófilos, linfócitos e eosinógilos) induzidos pela elastase. Em relação a resposta inflamatória, o EcTI reduziu o número de neutrófilos e de células TNFalfa positivas no septo alveolar e nas vias aéreas além de reduzir o número de macrófagos no septo alveolar. Considerando o remodelamento de matriz extracelular, o inibidor de proteinase atenuou a fração de volume de fibras colágenas e o número de células MMP-9 e MMP-12 positivas nos septos alveolares e nas vias aéreas. Além disso, nas vias aéreas ocorreu uma atenuação da fração de volume de fibras elásticas, e nos septos alveolares uma atenuação da quantidade de células que expressam TIMP-1. Em relação a resposta de estresse oxidativo, o EcTI reduziu a fração de volume de isoprostano e o número de células iNOS e eNOS positivas tanto nos septos alveolares quanto nas vias aéreas. O EcTI também reduziu o número de células MUC5ac positivas nas vias aéreas. Conclusões: O tratamento como inibidor EcTI modulou a mecânica pulmonar e reduziu as alterações inflamatórias, de remodelamento e de estresse oxidativo induzidas pela elastase intratraqueal. Embora sejam necessários mais estudos para elucidar os mecanismos envolvidos neste processo, o inibidor de proteinase EcTI pode ser considerado como um potencial instrumento terapêutico para o tratamento da DPOC / Background: Proteinases play a key role on emphysema development, tissue destruction and mucus production. Enterolobium contortisiliquum Tripsin Inhibitor (EcTI) is a proteinase inhibitor from plant that neutralizes serine and cysteine proteinases. Aims: To evaluated the effects of the EcTI treatment in pulmonary alterations induced by elastase in mice. Methods: C57Bl6 mice received elastase intratracheally (50 uL/animal, ELA group) or saline (SAL group). Afterwards, mice were treated with EcTI (2 mg/kg) at days 1, 15 and 21 after elastase instillation (ELA-EcTI group). Control group received saline and EcTI using the same protocol (SAL-EcTI group). At day 28, mice were anesthetized, respiratory mechanics were collected, and exhaled nitric oxide were analyzed. Afterwards, broncoalveolar lavage fluid was obtained and lungs were removed to perform histochemistry and immunohistochemistry stains. By morphometry, the number of neutrophils, TNF-alfa, MMP-9, MMP-12, TIMP-1, iNOS, eNOS positive cells as well as the volume proportion of 8-iso-PGF2alfa, collagen and elastic fibers content in alveolar septum and airways walls were performed. In airways walls, we also analyzed the number of MUC-5 positive cells and the number of macrophages. Results: The proteinase inhibitor EcTI was able to reduce the pulmonary mechanical alterations (Ers, Htis and Raw), alveolar septum disruption (Lm) and the BAL cell count (total cells, macrophages, neutrophils, lymphocytes and eosinophils) induced by elastase. Regarding the inflammatory response, EcTI also reduced the number of neutrophils and TNFalfa positive cells in both alveolar septum and airway walls, and also reduced the number of macrophages in alveolar septum. Considering the extracellular matrix remodeling, the proteinase inhibitor attenuated the volume fraction of collagen fibers, MMP-9 and MMP-12 positive cells in both alveolar septum and airway walls. Besides, in airway there were attenuation in the volume fraction of elastic fibers, and in the alveolar septa a decrease of the amount of the cells expressing TIMP-1. Regarding the oxidative stress response, EcTI reduced the volume fraction of isoprostane and the number of iNOS and eNOS positive cells in both airways walls and alveolar septa, Finally, EcTI reduced the number of MUC5ac positive cells in airway walls. Conclusions: The treatment with EcTI modulated lung mechanics and reduced inflammatory, remodeling and oxidative stress alterations induced by elastase. Although more studies need to be performed to elucidate the mechanisms involved in this process, we may considerate EcTI as a potential therapeutic tool for COPD management
179

Efeito do inibidor de proteinase de origem vegetal EcTI, sobre a lesão pulmonar induzida pela elastase em camundongos C57BI6 / Effects of proteinase inhibitor from plant EcTI on elastase-induced lung alterations in mice

Osmar Aparecido Theodoro Junior 02 June 2014 (has links)
Introdução: As proteinases tem um papel importante no desenvolvimento, na destruição tecidual e na produção de muco causada pela DPOC. O inibidor de proteinase de origem vegetal Enterolobium contortisiliquum Tripsin Inhibitor (EcTI) inibe tanto as proteinases da classe serina quanto da classe cisteína. Objetivos: Avaliar os efeitos do tratamento com EcTI nas alterações pulmonares induzidas pela elastase em camundongos. Métodos: Camundongos C57Bl6 receberam elastase via intratraqueal (50 uL/animal, grupo ELA) ou salina (grupo SAL). Os camundongos foram tratados com EcTI (2mg/kg) nos dias 1, 15 e 21 após a instilação de elastase (grupo ELA-EcTI) ou salina (grupo SAL-EcTI). No dia 28 do protocolo, os animais foram anestesiados, a mecânica pulmonar foi medida e o óxido nítrico exalado coletado. Posteriormente, foi realizado o lavado broncoalveolar e os pulmões foram removidos para a preparação de lâminas de histoquímica e imunohistoquímica. Por meio de morfometria analisamos o número de células positivas para neutrófilos, TNF-alfa, MMP-9, MMP-12, TIMP-1, iNOS, eNOS assim como a fração de volume de 8-iso-PGF2alfa, fibras colágenas e elásticas, nos septos alveolares e nas vias aéreas. Também foram avaliados o número de células positivas para macrófagos nos septos alveolares e MUC5ac nas vias aéreas. Resultados: O inibidor de proteinase EcTI reduziu as alterações de mecânica pulmonar (Ers, Htis e Raw), destruição do septo alveolar (Lm) e o número de células no lavado broncoalveolar (células totais, macrófagos, neutrófilos, linfócitos e eosinógilos) induzidos pela elastase. Em relação a resposta inflamatória, o EcTI reduziu o número de neutrófilos e de células TNFalfa positivas no septo alveolar e nas vias aéreas além de reduzir o número de macrófagos no septo alveolar. Considerando o remodelamento de matriz extracelular, o inibidor de proteinase atenuou a fração de volume de fibras colágenas e o número de células MMP-9 e MMP-12 positivas nos septos alveolares e nas vias aéreas. Além disso, nas vias aéreas ocorreu uma atenuação da fração de volume de fibras elásticas, e nos septos alveolares uma atenuação da quantidade de células que expressam TIMP-1. Em relação a resposta de estresse oxidativo, o EcTI reduziu a fração de volume de isoprostano e o número de células iNOS e eNOS positivas tanto nos septos alveolares quanto nas vias aéreas. O EcTI também reduziu o número de células MUC5ac positivas nas vias aéreas. Conclusões: O tratamento como inibidor EcTI modulou a mecânica pulmonar e reduziu as alterações inflamatórias, de remodelamento e de estresse oxidativo induzidas pela elastase intratraqueal. Embora sejam necessários mais estudos para elucidar os mecanismos envolvidos neste processo, o inibidor de proteinase EcTI pode ser considerado como um potencial instrumento terapêutico para o tratamento da DPOC / Background: Proteinases play a key role on emphysema development, tissue destruction and mucus production. Enterolobium contortisiliquum Tripsin Inhibitor (EcTI) is a proteinase inhibitor from plant that neutralizes serine and cysteine proteinases. Aims: To evaluated the effects of the EcTI treatment in pulmonary alterations induced by elastase in mice. Methods: C57Bl6 mice received elastase intratracheally (50 uL/animal, ELA group) or saline (SAL group). Afterwards, mice were treated with EcTI (2 mg/kg) at days 1, 15 and 21 after elastase instillation (ELA-EcTI group). Control group received saline and EcTI using the same protocol (SAL-EcTI group). At day 28, mice were anesthetized, respiratory mechanics were collected, and exhaled nitric oxide were analyzed. Afterwards, broncoalveolar lavage fluid was obtained and lungs were removed to perform histochemistry and immunohistochemistry stains. By morphometry, the number of neutrophils, TNF-alfa, MMP-9, MMP-12, TIMP-1, iNOS, eNOS positive cells as well as the volume proportion of 8-iso-PGF2alfa, collagen and elastic fibers content in alveolar septum and airways walls were performed. In airways walls, we also analyzed the number of MUC-5 positive cells and the number of macrophages. Results: The proteinase inhibitor EcTI was able to reduce the pulmonary mechanical alterations (Ers, Htis and Raw), alveolar septum disruption (Lm) and the BAL cell count (total cells, macrophages, neutrophils, lymphocytes and eosinophils) induced by elastase. Regarding the inflammatory response, EcTI also reduced the number of neutrophils and TNFalfa positive cells in both alveolar septum and airway walls, and also reduced the number of macrophages in alveolar septum. Considering the extracellular matrix remodeling, the proteinase inhibitor attenuated the volume fraction of collagen fibers, MMP-9 and MMP-12 positive cells in both alveolar septum and airway walls. Besides, in airway there were attenuation in the volume fraction of elastic fibers, and in the alveolar septa a decrease of the amount of the cells expressing TIMP-1. Regarding the oxidative stress response, EcTI reduced the volume fraction of isoprostane and the number of iNOS and eNOS positive cells in both airways walls and alveolar septa, Finally, EcTI reduced the number of MUC5ac positive cells in airway walls. Conclusions: The treatment with EcTI modulated lung mechanics and reduced inflammatory, remodeling and oxidative stress alterations induced by elastase. Although more studies need to be performed to elucidate the mechanisms involved in this process, we may considerate EcTI as a potential therapeutic tool for COPD management
180

Étude de l'implication neurologique et immunologique de la voie costimulatrice CD27/CD70 dans la sclérose en plaques

Tremblay, Laurence 05 1900 (has links)
No description available.

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