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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Matrix metalloproteinases (MMPs) and their specific tissue inhibitors (TIMPs) in mature human odontoblasts and pulp tissue:the regulation of expressions of fibrillar collagens, MMPs and TIMPs by growth factors, transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2)

Palosaari, H. (Heidi) 15 August 2003 (has links)
Abstract Dentin formation in physiological and pathological conditions has been widely studied, but the events and regulation are still not completely understood. Odontoblasts, terminally differentiated post-mitotic cells located in a single cell layer around pulp tissue, synthesize and mineralize dentin organic matrix. Growth factors, such as TGF-β1 and BMP-2, have been implicated in the regulation of the responses of odontoblasts and pulp tissue to external irritation. Matrix metalloproteinases (MMPs), a family of 28 endopeptidases collectively capable of degrading virtually all extracellular matrix components, and their specific tissue inhibitors (TIMPs) participate in the organo- and morphogenesis, physiological tissue turnover and pathological tissue destruction in many tissues, but very little is known about their presence, function, and regulation in the dentin-pulp complex cells and tissues. The aim of the work presented in this thesis was to analyze the expression and regulation of collagens, MMPs and TIMPs by TGF-β1 and BMP-2 in mature human odontoblasts and pulp tissue. Odontoblasts synthesize and secrete type I and type III collagens, with no clear effect of TGF-β1 on their expression levels. MMP-1, -2, -8, -9, -10, -11, -14, -15, -16, -19 and TIMP-1, -2, -3 and -4 were expressed by both odontoblasts and pulp tissue. MMP-3 and MMP-12 were not expressed in native odontoblasts or pulp tissue, and MMP-7, -24, and -25 were expressed only in odontoblasts. MMP-2, -10, -14, -20 and -23 were expressed more abundantly in odontoblasts, whereas pulp tissue expressed more MMP-13 and MMP-17. Growth factors differentially regulated the expression of different MMPs and TIMPs within and among the cells and tissues studied. In odontoblasts, MMP-1, -8 and -14 were down-regulated, but MMP-7, MMP-9, TIMP-1 and TIMP-3 up-regulated, by either TGF-β1 or BMP-2, alone or in combination. In pulp tissue, growth factors up-regulated the expression of MMP-1, -2, -10, -13, -17 and TIMP-3, but down-regulated TIMP-4. The widespread of expression of MMPs and TIMPs by mature human odontoblasts and pulp tissue suggests that they may participate in dentin matrix organization prior to mineralization, and that growth factors may further control dentin matrix modeling, not by regulating the synthesis of type I or III collagens as previously believed, but rather by differentially regulating each MMPs and TIMPs.
22

The prognostic role of matrix metalloproteinases MMP-2 and -9 and their tissue inhibitors TIMP-1 and -2 in primary breast carcinoma

Kuvaja, P. (Paula) 23 October 2007 (has links)
Abstract Breast carcinoma is a heterogeneous disease with a prognosis that varies from excellent to very poor. Traditional tumour parameters and biological factors that are also predictive for treatment response are used in determining breast carcinoma prognosis and selecting appropriate treatment. Gelatinases MMP-2 and MMP-9 have been shown to associate with tumour progression. Their tissue inhibitors TIMP-1 and -2 are multifunctional molecules that have been suggested as prognostic markers in some previous reports. In the present work, the expression and prognostic value of gelatinases MMP-2 and MMP-9 and their tissue inhibitors TIMP-1 and -2 were assessed in primary breast carcinoma. The material consisted of a total of 416 patients. Tissue expression of TIMP-1 and -2 was analysed in a population of 203 patients using immunohistochemistry. Circulating gelatinases and their inhibitors were studied using ELISA in two different populations of 71 at preoperative state and 213 patients at pre- and postoperative state. High expression of TIMP-1 immunoreactive protein positively correlated with high histological grade of the tumour and associated with aggressive disease course in grade 2–3 subpopulation. High preoperative plasma TIMP-1 was prognostic for relapse in a modern patient series after a median follow-up time of 18 months. TIMP-1 as a continuous variable was prognostic in Cox regression univariate analysis, and was an independent prognostic variable superior to nodal status in multivariate analysis. High preoperative serum TIMP-1 was an independent prognostic variable for poor disease-specific survival, and TIMP-1 was found to maintain its prognostic value when assessed independently with different ELISA analyses, and was not very sensitive for preanalytical conditions. In addition, low circulating preoperative serum MMP-2 was observed to associate with high stage and positive nodal status in breast carcinoma. These results indicate that circulating TIMP-1 may be a potential new marker of worsened prognosis in breast carcinoma, although careful validation of assay platforms and identification of the sources of physiological variation are needed before it can be adopted into clinical decision-making.
23

Cell lineage specific expression of matrix metalloproteinases -2 and -9 in transgenic mice

Salonurmi, T. (Tuire) 28 May 2004 (has links)
Abstract Mammalian extracellular matrix metalloproteinases, MMPs, are a family of enzymes capable of degrading components of the connective tissue. The in vivo regulation of the cell lineage-specific expression of MMPs, however, is not well known. This study used transgenic mice to identify cell-specific elements in the upstream regulatory regions of MMP-2 and MMP-9. Transgenic mice were generated by pronuclear microinjections into fertilised oocytes using lacZ as a reporter gene. The reporter gene constructs containing varying lengths of the MMP-9 5'-upstream region revealed an area that allowed for expression in osteoclasts and migrating keratinocytes, the cells that also express MMP-9 in vivo. The sequence driving the cell specific expression included the nucleotides from -2722 to -7745. When the same upstream regulatory fragment of MMP-9 was used to drive the expression of the human tissue specific inhibitor of MMPs, TIMP-1, instead of lacZ, the transgenic mice developed normally and the animals were fertile with normal post-embryonic growth. However, cutaneous wound healing was remarkably retarded, but not totally prevented, and the migration of keratinocytes over the wound was slow. The mice expressed the human TIMP-1 in keratinocytes during wound healing and in situ zymography revealed a total blockage of the gelatinolytic activity of MMP-2 and MMP-9, the main gelatinases active in the healing wound tissues. By using a sequence of 6500 base pairs from the 5'-upstream regulatory region of the MMP-2 gene it was possible to drive the expression of lacZ in mesenchymal cells of the developing transgenic mouse embryo. The expression pattern was similar to that found in previous in situ hybridization studies, following the different stages of tissue morphogenesis and being present in the areas of basement membrane degradation and epithelial cell invasion. Computer analyses of the sequence revealed three regulatory upstream regions conserved between human, mouse, and rat, and possibly responsible for the cell-and tissue specificity. New transgene constructs containing fragments of the conserved regions will provide a more detailed profile of the in vivo MMP-2 regulation in the future. This study defined a fragment in the upstream regulatory region of MMP-9 that is essential for expression in osteoclasts and migrating keratinocytes. Furthermore, the keratinocyte derived MMPs, including MMP-9, were found to play important role in epithelial cell migration in the area of the healing wound.
24

O papel dos biomarcadores como preditores diagnósticos e prognósticos da lesão renal aguda associada ao uso de vancomicina

Garms, Durval Sampaio de Souza January 2020 (has links)
Orientador: Daniela Ponce / Resumo: A prevalência da Lesão Renal Aguda (LRA) associada ao uso da vancomicina é muito variável e diferentes fatores relacionados ao paciente e ao tratamento (tempo e dose) podem potencializar a ocorrência da nefrotoxicidade. Estudos relacionaram o desempenho de biomarcadores urinários como preditores diagnósticos e prognósticos de LRA na insuficiência cardíaca (ICC), no pós-operatório de cirurgia cardíaca e na sepse, porém, pouco se sabe sobre o desempenho dos novos biomarcadores na LRA associada ao uso da vancomicina. / Abstract: The prevalence of acute kidney injury (AKI) related to vancomycin is variable and different risk factors related to the patient and the treatment (time and dose) may potentiate the occurrence of nephrotoxicity. Studies related the performance of urinary biomarkers as predictors of diagnostic and prognostic AKI in congestive heart failure (CHF), in the postoperative period of cardiac surgery and in sepsis, however, little is known about the performance of the new urinary biomarkers in vancomycin related AKI. / Mestre
25

Angiotensin II induces TIMP-1 production in rat heart endothelial cells

Chua, Chu Chang, Hamdy, Ronald C., Chua, Balvin H.L. 28 May 1996 (has links)
Angiotensin II (All) was found to upregulate tissue inhibitor of metalloproteineses-1 (TIMP-1) gene expression in rat heart endothelial cells in a dose and time-dependent manner. The maximal stimulation of TIMP-1 mRNA was achieved by 2 h after the addition of All. This effect was blocked by losartan, an AT1 receptor antagonist and by calphostin C, a protein kinase C inhibitor. Addition of cycloheximide superinduced and actinomycin D abolished the induction. These results suggest that All stimulates TIMP-1 production by a protein kinase C dependent pathway which is dependent upon de novo RNA synthesis. Immunoprecipitation experiment showed an enhanced band of 28 kDa from the conditioned medium of All-treated cultures. Immunoblot analysis revealed that TIMP-1 was detectable in the conditioned medium 4 h after All stimulation. Since endothelial cells line the blood vessels and sense the rise in All associated with hypertension, the TIMP-1 released by these cells may provide an initial trigger leading to cardiac fibrosis in angiotensin-renin dependent hypertension.
26

Untersuchungen zu TNF in Monozyten von Patienten mit RA und gesunden Spendern

Mathar, Christoph 26 February 2018 (has links)
Die Rheumatoide Arthritis ist die häufigste inflammatorische Arthritis mit einer Prävalenz von 0.5-1%. Pathophysiologisch spielen intrinsische Dysregulationen der Zytokinexpression insbesondere von TNF von Monozyten eine bedeutende Rolle. Die Regulation der TNF Expression ist komplex und manifestiert sich in erster Linie posttranslational. Hier steht das proteolytische Shedding durch die Metalloproteinase TACE, sowie deren Inhibierung durch TIMP-3 im Vordergrund. Ziel der Arbeit war die Aufdeckung potentieller Fehlsteuerungen der monozytären TNF Expression und der betreffenden regulatorischen Proteine, sowohl auf Ebene der mRNA Expression als auch posttranslational. Es konnte gezeigt werden, das Monozyten von RA Patienten vermehrt intrazelluläres TNF exprimieren. Der Anteil TIMP-3 positiver Monozyten scheint bei RA Patienten tendenziell vermindert zu sein.:1. Einleitung 1 1.1. Die Rheumatoide Arthritis 1 1.1.1. Epidemiologie und Klinik 1 1.1.2. Ätiologie und Pathogenese 1 1.2 Der Tumornekrosefaktor 3 1.2.1 Struktur und Signaltransduktion von TNF 4 1.2.2 Regulationsmechanismen der TNF Expression in Monozyten 5 1.3 Fragestellung und Ziele 9 2. Material und Methoden 11 2.1 Rekrutierung von Patienten und gesunden Probanden 11 2.2 Materialien 12 2.3 Methoden 15 2.3.1 Separation von PBMCs mittels Dichtegradientenzentrifugation 15 2.3.2 Separation von Monozyten mit negativer Magnetseparation 15 2.3.3 Bestimmung der monozytären Expression von TACE mittels Durchflusszytometrie 16 2.3.4 Bestimmung der intrazellulären Expression von TNF, TIMP-3 und PR-3 in Monozyten 17 2.3.5 Messung der TNF und TNF Rezeptor 2 Sekretion von Monozyten mit Hilfe eines ELISA 17 2.3.6 Bestimmung der RNA Expression von TNF, TIMP-3,TACE und PR-3 in Monozyten mittels Real Time PCR 19 2.4 Statistische Auswertung 20 3. Ergebnisse 21 3.1 Deskriptive Statistik der Kohorten 21 3.2 Expression der mRNA von TNF, TACE, TIMP-3 und PR-3 in Monozyten 22 3.3 Expression von TACE auf Monozyten 23 3.4 Expression von intrazellulärem TNF, TIMP-3 und PR-3 in Monozyten 24 3.5 Sekretion von TNF und TNFR2 von Monozyten 28 4. Diskussion 32 4.1 Expression von TNF sowie regulatorischer Moleküle auf mRNA Ebene 32 4.2 Expression von tmTNF und TACE auf der Oberfläche von Monozyten 35 4.3 Intrazelluläres Vorkommen von TNF sowie regulatorischer Moleküle in Monozyten 36 4.4 Sekretion von TNF und TNFR2 durch Monozyten 39 5. Zusammenfassung 42 6. Literaturverzeichnis 47 7. Abbildungsverzeichnis 61 8. Eigenständigkeitserklärung 63 9. Lebenslauf 63 10. Danksagung 65
27

TIMP-1 Activates a Unique Cardiac Stem Cell Population, CD63+ve/C-KIT+ve, Thereby Enhancing Cardiac Differentiation, and Protects the Heart From Adverse Cardiac Remodeling Following Myocardial Infarction

Abdelli, Latifa 01 January 2015 (has links)
We previously demonstrated that embryonic stem (ES) cells over-expressing tissue inhibitor of metalloproteinase-1 (TIMP-1) have increased potential to engraft and differentiate into cardiac myocytes following transplantation into the infarcted heart. However, the ability of TIMP-1 to activate endogenous stem cells and enhance their differentiation into cardiac regenerative cell types is still unknown. We postulate that TIMP-1 may additionally activate a stem cell population that enhances cardiac cell type differentiation in the infarcted myocardium. To prove this hypothesis, we isolated c-kit+ve cells from four weeks old C57BL/6 mice and cultured them in vitro in presence of ES conditioned media (ESCM), ES-TIMP-1-CM or TIMP-1. Our immunostaining data validate the existence of a novel CD63+ve/c-kit+ve cells. When treated with TIMP-1, these cells showed significantly (p < 0.05) increased proliferation and differentiation into cardiac myocytes, vascular smooth muscle cells, and endothelial cells. Western blot analysis revealed significantly (p < 0.05) increased expression of CD63, phosphorylated and total β-catenin proteins. Furthermore, our RT-PCR data showed increased cardiac gene expression (GATA-4, Mef2C, and Nkx-2.5) when compared to ESCM and control cells. Based on the in vitro findings, we investigated the effect of intramyocardial delivery of TIMP-1 on endogenous CD63+ve/c-kit+ve cells following myocardial infarction (MI). C57BL/6 and TIMP-1 KO mice underwent coronary artery ligation followed by intramyocardial delivery of 20μl of culture media (CC), ESCM, ES-TIMP-1-CM or TIMP-1. Subsequent immunohistochemistry analysis demonstrated the presence of a CD63+ve/c-kit+ve cell population within the peri-infarct area and confirmed intramyocardial delivery of ES-TIMP-1-CM or TIMP-1 significantly (p < 0.05) enhanced their proliferation. Percentage of CD63+ve/c-kit+ve cells was significantly (p < 0.05) lower in TIMP-1 KO mice compared to C57BL/6 animals. RT-PCR analysis revealed TIMP-1 KO animals expressed significantly less CD63 and TIMP-1 mRNAs compared to C57BL/6 mice. Activated CD63+ve/c-kit+ve cells were also able to differentiate into major cardiac cell types as previously shown in vitro. The differentiation potential of these cells was however higher in C57BL/6 mice compared to TIMP-1 KO mice. We also demonstrate that CD63+ve/c-kit+ve cells differentiation is regulated by CD63/β-catenin pathway in vivo. Additionally, we provide evidence that TIMP-1 protects the heart from adverse cardiac remodeling through inhibition of cardiac apoptosis and fibrosis leading to significantly (p < 0.05) improved contractile function. Collectively, our data show TIMP-1 plays a dual protective role in the MI heart. It activates a unique stem cell population, CD63+ve/c-kit+ve, which proliferates and differentiates into functional myocytes, smooth muscle cells and endothelial cells mediated through CD63/β-catenin pathway. TIMP-1 also protects the heart from adverse cardiac remodeling. Increased cardiac regeneration and inhibition of adverse cardiac remodeling consequently lead to restored cardiac function.
28

Ciblage de la nucléoline de surface par les pseudopeptides NucAnts dans l’inhibition de la croissance tumorale et de l’angiogenèse associée / Targeting cell surface-expressed nucleolin by NucAnts pseudopeptides in tumor growth and associated angiogenesis inhibition

Destouches, Damien 08 December 2009 (has links)
La recherche contre le cancer est aujourd’hui tournée vers les thérapies ciblées. Dans ce contexte, la nucléoline et la nucléophosmine sont fortement impliquées dans la croissance tumorale et l’angiogenèse associée et surexprimées dans les cellules tumorales et endothéliales activées. Elles apparaissent donc comme des cibles de choix. Le pseudopeptide HB-19 lie la nucléoline de surface, inhibe la croissance cellulaire de nombreuses lignées de cellules tumorales et induit la mort de ces cellules tumorales par apoptose. D’autre part, il inhibe, in vitro et in vivo, plusieurs étapes de l’angiogenèse tumorale. Ces deux activités mènent, in vivo, à l’inhibition de la croissance tumorale dans de nombreux modèles de croissance tumorale chez la souris. Dans le but d’améliorer les activités observées avec HB- 19, des pseudopeptides dérivés de ce dernier ont été synthétisés. Ainsi le NucAnt 6L (N6L) montre une activité 5 à 10 fois supérieure à celle de HB-19 selon les modèles. Son activité anti-métastatique a également été démontrée. L’étude du mécanisme d’action des pseudopeptides a permis d’identifier deux nouveaux récepteurs: les héparanes sulfates et la nucléophosmine. L’importance du TIMP-3 dans son activité anti-métastatique a également été soulignée. Enfin, aucune toxicité n’a été observée chez les souris aux doses employées et la synthèse de N6L peut être effectuée à l’échelle industrielle. N6L apparaît donc comme un composé prometteur pour une thérapie anti-cancéreuse / The cancer research is nowadays interested in targeting therapies. In this context, nucleolin and nucleophosmin are proteins highly involved in tumor growth and angiogenesis and over-expressed in activated endothelial and tumor cells. So, they appear as very promising targets. The pseudopeptide HB-19 binds to cell surface-expressed nucleolin, inhibits different tumor cell growth and induces cell death by apoptosis. Furthermore, it inhibits, in vitro and in vivo, several steps of angiogenesis. These two activities lead, in vivo, to the suppression of tumor growth and angiogenesis in several mice models. In order to improve the activities observed with HB-19, new compounds derived from HB-19 were synthesized. So, NucAnt 6L (N6L) show 5 to 10 fold stronger anti-tumoral activity than HB- 19 depending of the model. Study of their action mechanism allowed us to identify two new receptors: nucleophosmin and heparan sulfates. The importance of TIMP-3 in anti-metastatic activity has also been highlighted. Finally, no toxicity has been observed in mice treated with N6L which can easily industrially be synthesized. N6L appears to be a promising compound for anti-cancer therapies
29

Efeito da terapia com c?lulas mononucleares de medula ?ssea em perfura??es agudas de membrana timp?nica

Fabricio, Daniela Dias 17 March 2009 (has links)
Made available in DSpace on 2015-04-14T13:34:41Z (GMT). No. of bitstreams: 1 412790.pdf: 4945836 bytes, checksum: ee40952653059296bd5709107e36417b (MD5) Previous issue date: 2009-03-17 / INTRODU??O: As c?lulas mononucleares de medula ?ssea t?m sido utilizadas em diversas patologias na tentativa de regenera??o tecidual. O objetivo deste estudo foi avaliar o seu potencial efeito na cicatriza??o de perfura??es agudas da membrana timp?nica (MT). M?TODOS: Foram realizadas perfura??es timp?nicas bilateralmente por meio de miringotomia em 10 ratos Wistar. C?lulas mononucleares de medula ?ssea foram utilizadas de um lado e solu??o fisiol?gica no lado contralateral. Avaliou-se o tempo de cicatriza??o, a mobilidade timp?nica e a histologia. RESULTADOS: O lado que utilizou c?lulas mononucleares cicatrizou em m?dia 3 dias antes que o controle (p=0,006). N?o houve diferen?a de mobilidade ou padr?o histol?gico entre os grupos. CONCLUS?O: As c?lulas mononucleares de medula ?ssea proporcionaram uma cicatriza??o mais r?pida da MT que o grupo controle.
30

Migration on extracellular matrix surface and infiltration into matrix - two distinguishable activities of human T cells

Ivanoff, Jyrki January 2003 (has links)
<p>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.</p>

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