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Migration on extracellular matrix surface and infiltration into matrix - two distinguishable activities of human T cellsIvanoff, Jyrki January 2003 (has links)
Migration of T-lymphocytes on a surface coated with extracellular matrix (ECM) components (two-dimensional (2-D) migration) and migration (infiltration) into a matrix (Three-dimesional (3-D) migration) are complex events and the underlying mechanisms are not yet fully understood. Here 2-D and 3-D migration were studied by use of seven leukemic T-cell lines representing discrete differentiation stages, a non-leukemic T-cell clone, and normal peripheral blood T cells. peripheral blood lymphocytes and the T-cell clone produced nanogram quantities of various chemokines, as compared to a production of ≤ 0.05 ng/ml by the T leukemia cell lines. In a Boyden chamber system, the leukemic T-cell lines showed haptotactic migration on fibronectin. The migration was augmented bu exposure to chemokines, including RANTES, MIP-1α, MIP-1β, and IL-8. The T-cell lines showed a peak response at a chemokine concentration of 10-50 ng/ml, whereas the T-cell clone responded optimally at 100 ng/ml. In contrast to a general capability of T-cells to migrate on 2-D ECM, only some of the T-cell lines were capable of 3-D migration into Matrigel or a collagen matrix. The infiltrative capacity was unrelated to the capacity to migrate on or adhere to the substrata. T-cell lines with a capacity to infiltrate produced matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), whereas non-infiltrating cell lines did not produce MMP-9. T-cell lines capable of infiltrating Matrigel or collagen responded to chemokines exposure with increased infiltration, but the chemokines did not render non-infiltrative cell lines infiltrative. Stimulation of infiltration of T-cell lines into collagen by the chemokine SDF-1α was inhibited by somatostatin, a neuropeptide with immunosuppressive properties. In conclusion, the ability to migrate on 2-D substrata and to infiltrate into 3.D substrata was found to be distinguishable properties of T cells. failure of some T-cell lines to infiltrate correlated with the lack of expression of MMP-9. Chemokines stimulated infiltration of infiltrative T-cell lines into collagen and Matrigel but did not render non-infiltrative T-cell lines infiltrative. Finally, a possible physiological mechanism for modulation of the chemokine-stimulated 3-D migration was demonstrated.
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Aação do extrato etanólico da casca do pequi na cardiotoxicidade por doxorrubicina em ratos / Effects of pequi shell ethanolic extract in doxorubicin cardiotoxicity in ratsMoura, Léa Resende 10 December 2015 (has links)
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Previous issue date: 2015-12-10 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / This study aimed to evaluate the effects of pequi shell etanolic extract (PSEE) (Caryocar brasiliense), through morphological evaluation and expression of MMP2, MMP9, TIMP1 and TIMP2 proteins in the myocardium of rats with experimental acute and chronic doxorubicin (DOX) cardiotoxicity, to better understand the mechanisms involved in this disease process. Thus, two experiments were carried out. In experiment groups of acute phase, 30 Wistar rats were divided in six groups of five animals each, being Sham group (SG) water and saline; (G1) 16 mg/kg DOX and treatment with 300 mg/kg of PSEE for 17 days; (G2) 16 mg/kg of DOX and 600 mg/kg of PSEE for 17 days; (G3) 16 mg/kg of DOX and 300 mg/kg of PSEE for 10 days; (G4) 16 mg/kg of DOX and 600 mg/kg of PSEE for 10 days; and (GC) 16 mg/kg DOX. Treatment of G1 and G2 began on day one and continued until the end of the experiment, on the 17th. G3 and G4 animals were treated with PSEE for ten days, from the day seven, and DOX was applied on the 14th day after the experiment beginning. Three days after the application of DOX, on the 17th, the animals were euthanized and macroscopic evaluation and collection of samples for enzymatic analysis, histopathology and immunohistochemistry were performed. In groups of the chronic phase experiment, 30 Wistar rats were divided in six groups of five animals. G1 and G2 received 300 mg/kg and 600 mg/kg of PSEE, respectively, as pretreatment, by gavage for seven days. In G1, G2, G3, G4 and control group (CG), cardiotoxicity was induced with weekly applications of 2 mg/kg DOX, intraperitoneally, totaling four applications (8 mg/kg), and Sham group (SG) received 1 ml saline solution. G3 animals received daily 300 mg/kg of PSEE and G4, 600 mg/kg, by gavage, for 21 days of application of DOX. The CG and SG received 1 ml of water daily by gavage also. After completion of the application animals were kept for two months, totaling three months of treatment. Macroscopic evaluation was performed by the 90 days and samples were taken for analysis in electron microscopy, histopathology and immunohistochemistry. In acute experiment was concluded that PSEE attenuates the the deleterious effects of the DOX on cardiac muscle undergoing acute drug-induced cardiotoxicity. When used at doses of 300 and 600 mg/kg for 17 days PSEE attenuates vacuolar degeneration in myocytes. When used at a dose of 600 mg/kg for 10 days PSEE reduces the fibers disruption. PSEE at a dose of 300 mg/kg for 17 days increases TIMP1 expression in the myocardium of rats treated with DOX. In chronic experiment was concluded that PSEE is effective in minimizing effects of chronic cardiotoxicity induced by DOX in the myocardium of rats, whereas at doses of 300 and 600 mg/kg, PSEE attenuates vacuolar degeneration in myocytes and at the dose of 600 mg/kg the PSEE reduces the amount of Anitschkow cells and myofibrils fragmentation.
Keywords: Anthracycline, electron microscopy, histopathology / O presente estudo teve como objetivo avaliar a ação do extrato etanólico da casca do pequi (EECP) (Caryocar brasiliense), por meio de avaliação morfológica e expressão das proteínas MMP2, MMP9, TIMP1 e TIMP2, no miocárdio de ratos submetidos à cardiotoxicidade experimental aguda e crônica pela doxorrubicina (DOX), visando melhor entendimento dos mecanismos envolvidos nesse processo patológico. Para isso, foram realizados dois experimentos. Nos grupos do experimento de fase aguda, foram utilizados 30 ratos da raça Wistar, distribuídos em seis grupos de cinco animais cada, sendo grupo Sham (GS) água e solução salina; (G1) 16 mg/kg de DOX e tratamento com 300 mg/kg de EECP durante 17 dias; (G2) 16 mg/kg de DOX e 600 mg/kg de EECP durante 17 dias; (G3) 16 mg/kg de DOX e 300 mg/kg de EECP durante 10 dias; (G4) 16 mg/kg de DOX e 600 mg/kg de EECP durante 10 dias; e grupo controle (GC) 16 mg/kg de DOX. O tratamento de G1 e G2 teve início no dia um e estendeu-se até o término do experimento, no dia 17. Os animais de G3 e G4 foram submetidos a tratamento com EECP durante 10 dias, a partir do dia sete, e a DOX foi aplicada no 14° dia após o início do experimento. Três dias após a aplicação da DOX, no dia 17, os animais foram submetidos à eutanásia, avaliação macroscópica e colheita de amostras para análises histopatológica e imunoistoquímica. Nos grupos do experimento de fase crônica, foram utilizados 30 ratos da raça Wistar, distribuídos em seis grupos de cinco animais. G1 e G2 receberam como pré-tratamento com 300 mg/kg e 600 mg/kg de EECP, respectivamente, por gavagem, durante sete dias e mantiveram o tratamento durante os 21 dias de aplicação da DOX. Em G1, G2, G3, G4 e GC a cardiotoxicidade foi induzida com aplicações semanais de 2 mg/kg de DOX, via intraperitoneal, totalizando quatro aplicações (8 mg/kg) e, no GS foi aplicado 1 ml de solução fisiológica. Os animais de G3 receberam diariamente 300 mg/kg e os de G4 600 mg/kg de EECP, por gavagem, durante os 21 dias de aplicação da DOX. Os de GS e GC receberam 1 ml de água, diariamente, também por gavagem. Após o término das aplicações, os animais foram mantidos por dois meses em observação, totalizando três meses de experimento. A avaliação macroscópica foi realizada aos 90 dias, momento em que foram colhidas amostras para análise em microscopia eletrônica, histopatologia e imunoistoquímica. No experimento de fase aguda concluiu-se que o EECP minimiza os efeitos deletérios da DOX no miocárdio de ratos submetidos à cardiotoxicidade aguda induzida pelo fármaco. Quando utilizado nas doses de 300 e 600 mg/kg durante 17 dias o EECP atenua a degeneração vacuolar miocítica. Quando utilizado na dose de 600 mg/kg durante 10 dias o EECP reduz a desorganização das fibras. O EECP na dose de 300 mg/kg durante 17 dias aumenta a expressão de TIMP1 no miocárdio de ratos tratados com DOX. No experimento de fase crônica concluiu-se que o EECP é eficiente em minimizar os efeitos da cardiotoxicidade crônica induzida pela DOX no miocárdio de ratos, considerando que nas doses de 300 e 600 mg/kg, o EECP atenua a degeneração vacuolar miocítica e na dose de 600 mg/kg o EECP reduz a quantidade de células de Anitschkow e a fragmentação das miofibrilas.
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Biomaterials and the Foreign Body Reaction: Surface Chemistry Dependent Macrophage Adhesion, Fusion, Apoptosis, and Cytokine ProductionJones, Jacqueline Ann 16 April 2007 (has links)
No description available.
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Einfluss von Interleukin-1 beta auf die Expression und Sekretion der Adipokine TIMP-1, SAA-3, Lipocalin-2 und Chemerin in 3T3-L1 AdipozytenWeise, Sebastian 26 February 2013 (has links) (PDF)
Adipositas und ihre Folgeerkrankungen stellen eine wachsende medizinische Herausforde- rung globalen Ausmaßes dar. Im Rahmen der Adipositasforschung wurde das Fettgewebe als endokrines Organ identifiziert. Von ihm sezernierte Proteine, die sogenannten Adipo- kine, beeinflussen maßgeblich Insulinresistenz und Gefäßverletzbarkeit. Adipositas geht im Fettgewebe mit einer subklinischen chronischen Entzündung einher, die zu einer erhöhten Sekretion von proinflammatorischen Adipokinen führt. Die verstärkte Anwesenheit dieser Proteine ist mit den Komplikationen der Adipositas assoziiert. Die vorliegende Arbeit be- fasst sich mit dem Einfluss von Interleukin (IL)-1β, einem wichtigen Entzündungsmediator des Organismus, auf die Sekretion der proinflammatorischen Adipokine tissue inhibitor of metalloproteinase (TIMP)-1, serum amyloid A (SAA)-3, Lipocalin-2 und Chemerin.
Die zugrundeliegenden Untersuchungen wurden mit 3T3-L1- und braunen Adipozyten durch- geführt. Es erfolgte der Nachweis auf mRNA- sowie auf Proteinebene. Der Einsatz von spe- zifischen Inhibitoren erlaubte den Rückschluss auf grundlegende Signalwege.
Für alle vier untersuchten Adipokine konnte eine signifikante dosis- und zeitabhängige Steige- rung der mRNA- und Proteinexpression durch IL-1β nachgewiesen werden. Die Transduktion des IL-1β-Signals erfolgte im Falle von Lipocalin-2 und SAA-3 über nuclear factor (NF)-κB und janus kinase (Jak)-2, bei TIMP-1 lediglich über Jak-2 und in Bezug auf Chemerin über NFκB, Jak-2, p44/42 mitogen-activated protein kinase und Phosphatidylinositol-3-Kinase.
Die in dieser Arbeit nachgewiesenen Expressions- und Sekretionssteigerungen von TIMP-1, SAA-3, Lipocalin-2 und Chemerin in braunen und weißen Adipozyten festigen IL-1β als einen entscheidenden Mediator proinflammatorischer Prozesse im Fettgewebe. Eine umfassende Bewertung der Funktion von IL-1β im Fettgewebe, insbesondere im Zustand der Adipositas, muss jedoch in weitergehenden Studien erfolgen.
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Towards surgical use of matrix metalloproteinase biologyPasternak, Björn January 2008 (has links)
Matrix metalloproteinases (MMPs), such as collagenases, are a family of enzymes capable of degrading most constituents of the extracellular matrix. MMPs are thought to be involved in the aetiopathogenesis of tendon rupture. Additionally, failure of healing has in some instances been associated with elevated levels of MMPs. We have studied (a) the effects of the MMP-inhibitor doxycycline on healing of tendons and intestines in experimental models and (b) systemic levels of MMPs and their endogenous inhibitors (TIMPs) in patients with tendon rupture. In the first study, systemic doxycycline treatment lead to weakened rat Achilles tendons during healing after injury. Subsequently, systemic doxycycline was shown to improve biomechanical properties of tendon suture fixation in the rat Achilles tendon. Sutures were also coated with doxycycline, leading to similar improvement in mechanical strength of the suture construct during healing. In the third study, doxycycline-coated sutures improved the strength of healing intestinal anastomoses in an experimental model. Finally, we showed that patients with a history of Achilles tendon rupture had elevated levels of MMP-2, MMP-7 and TIMP-2 in serum. In addition, MMP-7 correlated inversely to mechanical strength of the tendon during healing. In conclusion, MMP-inhibitors can be administered systemically and locally to manipulate healing of tendons and intestines. Generalised alterations in the MMP-TIMP system may be involved in the pathogenesis of Achilles tendon rupture and associated with differences in outcome of healing.
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Analyse temps-frequence et traitement des signaux RSO à haute résolution spatiale pour la surveillance des grands ouvrages d'art / High-resolution time-frequency SAR signal processing for large infrastructure monitoringAnghel, Andrei 08 October 2015 (has links)
Cette thèse s'articule autour de deux axes de recherche. Le premier axe aborde les aspects méthodologiques liés au traitement temps-fréquence des signaux issus d'un radar FMCW (à onde continue modulée en fréquence) dans le contexte de la mesure des déplacements fins. Le second axe est dédié à la conception et à la validation d'une chaîne de traitement des images RSO (radar à synthèse d'ouverture) satellitaire. Lorsqu'un maillage 3D de la structure envisagée est disponible, les traitements proposés sont validés par l'intercomparaison avec les techniques conventionnelles d'auscultation des grands ouvrages d'art.D'une part, nous étudions la correction de la non-linéarité d'un radar FMCW en bande X, à courte portée, conçu pour la mesure des déplacements millimétriques. La caractéristique de commande non linéaire de l'oscillateur à large bande, entraine une perte de résolution à la réception. Afin de pallier cet inconvénient, nous avons développé deux méthodes basées sur le ré-échantillonnage temporel (time warping) dans le cas des signaux à large bande non-stationnaires. La première approche estime la loi de fréquence instantanée non linéaire à l'aide de la fonction d'ambiguïté d'ordre supérieur, tandis que la deuxième approche exploite la mesure de concentration spectrale du signal de battement dans un algorithme d'autofocus radial.D'autre part, nous proposons un cadre méthodologique général pour la détection et le pistage des centres de diffusion dans les images RSO pour la surveillance des grands ouvrages d'art. La méthode est basée sur la ré-focalisation de chaque image radar sur le maillage 3D de l'infrastructure étudiée afin d'identifier les diffuseurs pertinents par tomographie 4D (distance – azimut – élévation – vitesse de déformation). L'algorithme de ré-focalisation est parfaitement compatible avec les images RSO acquises dans les différents modes (« stripmap », « spotlight » et « sliding spotlight ») : dé-focalisation en azimut suivie par rétroprojection modifiée (conditionnée par la structure temps-fréquence du signal) sur l'ensemble donné des points. Dans la pile d'images ré-focalisées, les centres de diffusion sont détectés par tomographie 4D : test de conformité à l'hypothèse d'élévation zéro dans le plan élévation – vitesse de déformation. La vitesse moyenne correspond au maximum à l'élévation zéro, tandis que la série temporelle des déplacements est obtenue par double différence de phase des amplitudes complexes pour chaque diffuseur pertinent.Nous présentons également les campagnes in situ effectuées au barrage de Puylaurent (et glissement de Chastel) : les relevés GPS, topographiques et LIDAR sol employées au calcul des maillages 3D. La comparaison entre les déplacements mesurés in situ et les résultats obtenus par l'exploitation conjointe de la télédétection RSO satellitaires et les maillages 3D valident la chaîne de traitement proposée. / The thesis is composed of two research axis. The first one consists in proposing time-frequency signal processing tools for frequency modulated continuous wave (FMCW) radars used for displacements measurements, while the second one consists in designing a spaceborne synthetic aperture radar (SAR) signal processing methodology for infrastructure monitoring when an external point cloud of the envisaged structure is available. In the first part of the thesis, we propose our solutions to the nonlinearity problem of an X-band FMCW radar designed for millimetric displacement measurements of short-range targets. The nonlinear tuning curve of the voltage controlled oscillator from the transceiver can cause a dramatic resolution degradation for wideband sweeps. To mitigate this shortcoming, we have developed two time warping-based methods adapted to wideband nonlinearities: one estimates the nonlinear terms using the high order ambiguity function, while the other is an autofocus approach which exploits the spectral concentration of the beat signal. Onwards, as the core of the thesis, we propose a novel method for scattering centers detection and tracking in spaceborne SAR images adapted to infrastructure monitoring applications. The method is based on refocusing each SAR image on a provided 3D point cloud of the envisaged infrastructure and identifying the reliable scatterers to be monitored by means of four dimensional (4D) tomography. The refocusing algorithm is compatible with stripmap, spotlight and sliding spotlight SAR images and consists of an azimuth defocusing followed by a modified back-projection algorithm on the given set of points which exploits the time-frequency structure of the defocused azimuth signal. The scattering centers of the refocused image are detected in the 4D tomography framework by testing if the main response is at zero elevation in the local elevation-velocity spectral distribution. The mean displacement velocity is estimated from the peak response on the zero elevation axis, while the displacements time series for detected single scatterers is computed as double phase difference of complex amplitudes.Finally, we present the measurement campaigns carried out on the Puylaurent water-dam and the Chastel landslide using GPS measurements, topographic surveys and laser scans to generate the point clouds of the two structures. The comparison between in-situ data and the results obtained by combining TerraSAR-X data with the generated point clouds validate the developed SAR signal processing chain. / Teza cuprinde două axe principale de cercetare. Prima axă abordează aspecte metodologice de prelucraretimp-frecvenţă a semnalelor furnizate de radare cu emisie continuă şi modulaţie de frecvenţă (FMCW)în contextul măsurării deplasărilor milimetrice. În cadrul celei de-a doua axe, este proiectată şi validatăo metodă de prelucrare a imaginilor satelitare SAR (radar cu apertură sintetică) ce este destinatămonitorizării infrastructurii critice şi care se bazează pe existenţa unui model 3D al structurii respective.În prima parte a tezei, sunt investigate soluţii de corecţie a neliniarităţii unui radar FMCW în bandaX destinat măsurării deplasărilor milimetrice. Caracteristica de comandă neliniară a oscilatorului debandă largă determină o degradare a rezoluţiei în distanţă. Pentru a rezolva acest inconvenient, au fostelaborate două metode de corecţie a neliniarităţii, adaptate pentru semnale de bandă largă, ce se bazeazăpe conceptul de reeşantionare neuniformă sau deformare a axei temporare. Prima abordare estimeazăparametrii neliniarităţii utilizând funcţii de ambiguitate de ordin superior, iar cea de-a doua exploateazăo măsură de concentraţie spectrală a semnalului de bătăi într-un algoritm de autofocalizare în distanţă.În a doua parte a lucrării, este propusă o metodologie generală de detecţie şi monitorizare a centrilorde împrăştiere în imagini SAR în scopul monitorizării elementelor de infrastructură critică. Metoda sebazează pe refocalizarea fiecărei imagini radar pe un model 3D al structurii investigate în scopul identificăriicentrilor de împrăştiere pertinenţi (ţinte fiabile ce pot fi monitorizate în timp) cu ajutorul tomografiei SAR4D (distanţă-azimut-elevaţie-viteză de deplasare). Algoritmul de refocalizare este compatibil cu imaginiSAR achiziţionate în moduri diferite (« stripmap », « spotlight » şi « sliding spotlight ») şi constă într-odefocalizare în azimut urmată de o retroproiecţie modificată (condiţionată de structura timp-frecvenţă asemnalului) pe modelul 3D al structurii. Ţintele sunt identificate în stiva de imagini refocalizate cu ajutorultomografiei 4D prin efectuarea unui test de conformitate cu ipoteza că centrii de împrăştiere pertinenţivor avea elevaţie zero în planul local elevaţie-viteză. Viteza medie de deformare corespunde maximuluide pe axa de elevaţie nulă, iar seria temporară a deplasărilor se obţine printr-o dublă diferenţă de fază aamplitudinilor complexe corespunzătoare ţintelor identificate.În final sunt prezentate campaniile de măsurători pe teren efectuate la un baraj şi o alunecare de terendin regiunea Puylaurent (Franţa) destinate obţinerii modelului 3D al celor două elemente de infrastructurăprin măsurători GPS, topografice şi LIDAR. Comparaţia între deformările măsurate pe teren şi rezultateleobţinute prin combinarea imaginilor SAR cu modelele 3D au permis validarea metodologiei propuse.
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Translational perspectives on matrix metalloproteinase 8 and other inflammatory biomarkers in cardiovascular diseasesKormi, I. (Immi) 11 April 2017 (has links)
Abstract
Cardiovascular diseases (CVD), and especially atherosclerotic vascular diseases (ASVD), are the largest cause of morbidity and premature death worldwide. Coronary heart disease (CHD) and cerebrovascular disease (stroke) are common and severe manifestations of ASVD.
Atherosclerosis is a chronic inflammatory disease and lipoprotein metabolism disorder. If the regulation of inflammatory process is disturbed, the systemic release of pro-inflammatory mediators, including matrix metalloproteinases (MMPs), may lead to a low-grade systemic inflammation, which is a risk factor for CVDs. MMPs are enzymes that are responsible for the degradation of the extracellular matrix (ECM) during growth and tissue renewal but also in many pathological conditions. These ECM degrading proteases and their regulators play an important role in atherogenesis and subsequent plaque rupture, leading to acute cardiovascular manifestations. The pivotal role of MMPs in atherosclerosis has raised interest in the development of drug therapies targeting these proteases. Doxycycline has inhibitory effects on some MMPs in addition to its antimicrobial properties.
The main objective of this thesis project was to investigate the potential of these inflammatory mediators as biomarkers, risk factors, and therapeutic targets in CVD. The special focus was on MMP-8 and its main regulator, tissue inhibitor of matrix metalloproteinase (TIMP)-1.
The results of this study show that a high serum MMP-8 concentration indicates an acute cardiac condition and predicts a future CVD event. In addition to MMP-8, MMP-7 is a potential biomarker for incident CVD. The balance between these MMPs and their tissue inhibitor may indicate vulnerability to plaque rupture. Measurement of serum MMP-8 concentration is reliable, anti-invasive and inexpensive and can be done in hospital settings. We also show that regular-dose doxycycline decreases the systemic inflammatory burden in patients with earlier myocardial infarction and is a promising anti-inflammatory therapy in the prevention of CVDs with relatively minor side effects.
In conclusion, MMP-8 and TIMP-1 can be considered inflammatory risk markers of CVD events and death, and they can be utilized both for diagnostic and screening purposes. The inhibition of MMP-8 by doxycycline may reduce the systemic inflammatory burden in patients with myocardial infarction. / Tiivistelmä
Sydän- ja verisuonisairaudet, erityisesti ateroskleroottiset valtimosairaudet, ovat maailman yleisin sairastuvuuden ja ennenaikaisen kuoleman syy. Sepelvaltimotauti ja aivohaveri ovat ateroskleroottisen valtimosairauden yleisiä ja vakavia ilmenemismuotoja.
Ateroskleroosi on krooninen tulehduksellinen sairaus ja lipoproteiiniaineenvaihdunnan häiriö. Jos tulehdustapahtuma häiriintyy, elimistöön vapautuvat tulehdusvälittäjäaineet, kuten matriksin metalloproteinaasit (MMP), voivat aiheuttaa elimistön matala-asteisen tulehduksen, joka on sydän- ja verisuonisairauksien riskitekijä. MMP:t ovat entsyymejä, jotka pilkkovat solunväliainetta kasvun ja kudosten uusiutumisen mutta myös monien tautitilojen yhteydessä. Nämä soluväliainetta hajottavat proteaasit ja niiden säätelijät ovat tärkeässä roolissa ateroskleroottisen plakin muodostumisessa ja repeämisessä, joka johtaa äkillisiin sydäntautitapahtumiin. Matriksin metalloproteinaasien keskeinen rooli ateroskleroosissa on herättänyt kiinnostusta niihin kohdistuvan lääkehoidon kehittämiseen. Doksisykliinillä on joidenkin MMP-entsyymien toimintaa estävä vaikutus antimikrobiaalisten ominaisuuksiensa lisäksi.
Tämän väitöskirjatutkimuksen päätavoitteena oli tutkia näiden tulehdusvälittäjäaineiden mahdollisuuksia biomarkkereina, riskitekijöinä ja lääkehoidon kohteena sydän- ja verisuonisairauksissa. Erityinen kiinnostuksen kohde oli MMP-8 ja sen pääsäätelijä ja kudosestäjä, tissue inhibitor of matrix metalloproteinase (TIMP)-1.
Tämän tutkimuksen tulokset osoittavat, että seerumin korkea MMP 8 pitoisuus viittaa akuuttiin sydäntautiin ja ennakoi tulevaa sydäntautitapahtumaa. MMP-8:n lisäksi MMP-7 on lupaava sydäntapahtuman biomarkkeri. Näiden matriksin metalloproteinaasien ja niiden kudossäätelijä TIMP-1:n välinen tasapaino voi liittyä ateroskleroottisen plakin haurauteen. Seerumin MMP-8:n mittaus on luotettavaa, kajoamatonta ja edullista, ja mahdollista toteuttaa myös sairaalaolosuhteissa. Näytämme myös, että doksisykliini vähentää elimistön tulehdustaakkaa sydäninfarktin sairastaneilla potilailla ja että se on sydäntautien ehkäisyssä lupaava anti-inflammatorinen lääke, jolla on suhteellisen vähän sivuvaikutuksia.
Johtopäätöksenä on, että MMP-8:aa ja TIMP-1:tä voidaan pitää lupaavina sydän- ja verisuonitautien sekä kuoleman biomarkkereina sekä diagnostiikka- että seulontakäytössä. Lisäksi tutkimustulokset osoittavat, että MMP-8:n esto doksisykliinillä voi vähentää elimistön tulehdustaakkaa sydänkohtauksen sairastaneilla potilailla.
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Protease Expression Levels in Prostate Cancer Tissue Can Explain Prostate Cancer-Associated Seminal Biomarkers: An Explorative Concept StudyNeuhaus, Jochen, Schiffer, Eric, Mannello, Ferdinando, Horn, Lars-Christian, Ganzer, Roman, Stolzenburg, Jens-Uwe 16 January 2024 (has links)
Previously, we described prostate cancer (PCa) detection (83% sensitivity; 67% specificity) in
seminal plasma by CE-MS/MS. Moreover, advanced disease was distinguished from organ-confined
tumors with 80% sensitivity and 82% specificity. The discovered biomarkers were naturally occurring
fragments of larger seminal proteins, predominantly semenogelin 1 and 2, representing endpoints of
the ejaculate liquefaction. Here we identified proteases putatively involved in PCa specific protein
cleavage, and examined gene expression and tissue protein levels, jointly with cell localization in
normal prostate (nP), benign prostate hyperplasia (BPH), seminal vesicles and PCa using qPCR,
Western blotting and confocal laser scanning microscopy. We found differential gene expression of
chymase (CMA1), matrix metalloproteinases (MMP3, MMP7), and upregulation of MMP14 and tissue
inhibitors (TIMP1 and TIMP2) in BPH. In contrast tissue protein levels of MMP14 were downregulated
in PCa. MMP3/TIMP1 and MMP7/TIMP1 ratios were decreased in BPH. In seminal vesicles, we
found low-level expression of most proteases and, interestingly, we also detected TIMP1 and low
levels of TIMP2. We conclude that MMP3 and MMP7 activity is different in PCa compared to BPH
due to fine regulation by their inhibitor TIMP1. Our findings support the concept of seminal plasma
biomarkers as non-invasive tool for PCa detection and risk stratification.
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Expression and regulation of tissue inhibitor of metallaproteinases-4 in jointsHuang, Wensheng 12 1900 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal. / L'arthrite est une maladie qui affecte les articulations. Les métalloprotéases matricielles (MMPs) et les aggrécanases sont hautement exprimées chez les patients souffrant de l'arthrite rhumatoïde (RA) et de l'arthrose (OA). Quatre inhibiteurs tissulaires spécifiques des métalloprotéinases (TIMPs): TIMP-1, TIMP-2, TIMP-3 et TIMP-4, identifiées à date, sont capables d'abolir spécifiquement les activités des MMPs. La dégradation physiologique et pathologique de la matrice extracellulaire du cartilage est réglée par un équilibre entre MMPs et leurs inhibiteurs TIMPs, TIMP-4 étant le plus récent membre de la famille TIMP. La distribution tissulaire de TIMP-4 nous montre qu'elle est abondamment présente dans le tissu cardiaque, par contre elle est moins exprimée dans le foie, le rein, et les autres organes. l) Dans ce travail nous avons démontré pour la première fois que l'ARN et la protéine correspondante TIMP-4, sont exprimés dans le cartilage grâce aux techniques d'lmmunohistochimie, RT-PCR, et Western blot. Également nous avons mis en évidence que le gène TIMP-4 est exprimé dans le cartilage arthritique et non-arthritique. Le gène TIMP-4 est aussi exprimé dans les membranes synoviales, les chondrocytes primaires humaines et les chondrocytes bovines ainsi que dans le cartilage bovin. 2) Chez les patients la comparaison de l'expression du gène TIMP-4 indique bien la surexpression de ce dernier dans le cartilage des patients ostéoarthritiques et arthritiques. Nous avons remarqué que l'expression de TIMP-4 dans le cartilage chez les patients ostéoarthritiques, était principalement dans la zone superficielle du cartilage articulaire. Ceci suggère qu'il pourrait avoir un rôle dans le remodelage et dans le processus pathologique du cartilage arthritique. La présence et l'augmentation des TIMPs ne protègent pas contre la destruction du cartilage par une surabondance des MMPs et des aggrécanases. 3) La régulation de l'expression des MMPs, TIMP-1, TIMP-3 se fait par les cytokines et des facteurs de croissance inflammatoires : IL-1, TNF-α, l'oncostatin M (OSM) et TGF- β. Alors que celle de TIMP-4 n'est pas réglée par ces facteurs. Ceci suggère que TIMP-4 pourrait jouer un rôle distinct dans le processus de la maladie arthritique dont les mécanismes restent à étudier.
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Estudo dos efeitos da LDL (-) na angiogênese modelos in vitro e in vivo / Effects of LDL (-) on angiogenesis in vitro and in vivo modelsSangaletti, Laila Abicair 03 March 2008 (has links)
Diversas doenças estão associadas com a formação de novos vasos a parti vasos pré-existentes, ou angiogênese. Dentre elas está a aterosclerose (Griffioen & Molema, 2000). Pesquisas recentes demonstram que a hipercolesterolemia, que têm um papel importante na fisiologia da aterosclerose, também pode prejudicar a ação de fatores angiogênicos (Jang et.al., 2000). A hipercolesterolemia que é decorrente de aumento de LDL no plasma ocasiona um aumento no tempo de permanência desta partícula na circulação (Yasunobu, 2001). Contudo, a LDL pode sofrer modificação na circulação, dando origem a uma subfração mais eletronegativa da LDL, a LDL (-). A LDL (-) pode prejudicar cada etapa da angiogênese, desregulando a função endotelial (Tai et. al., 2006). Em nosso estudo, vimos que apesar da LDL (-) ter estimulado a miga celular, esta partícula inibiu a formação de túbulos in vitro. A LDL (-) não foi capa afetar a angiogênese in vivo. / A large number of diseases is associated with formation of new blood vessels out of pre-existing capillaries, or angiogenesis. These diseases include the atherosclerosis (Griffioen & Molema, 2000). Resents researches demonstrate that the hypercholesterolemia, that have a important role in the physiology of the atherosclerosis, can impaired the angiogenesis (Jang et. al., 2000) . The hypercholesterolemia that is decurrente of high levels of LDL in the plasma causes an increase in the time of permanence this particle in the circulation (Yasunobu, 2001). However, the LDL can to suffer modification in the circulation, giving rise to a subfration more eletronegative from LDL, the LDL (-). The LDL (-) could impair each one of the steps of the angiogenesis, thereby dysregulating endothelial function (Tai et. al., 2006). In our study, see that despite the LDL (-) have stimulated the cell migration, this particle inhibited the Tube formation in vitro. The LDL (-) didn\'t affect the angiogenesis in vivo.
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