Abstract To investigate the turnover of type IV collagen in skeletal muscle in conditions where muscle function is impaired, type IV collagen and proteins regulating its degradation were studied during 1, 3 and 7 days of immobilization, 3- and 10-day glucocorticoid treatment and in neuromuscular diseases. In addition, fibrillar type I and III collagens were studied during immobilization and in neuromuscular diseases. The mRNA levels of type I, III and IV collagens were decreased during immobilization and during 10-day dexamethasone treatment. Gene expression and quantity of (pro)MMP-2 was increased during immobilization but decreased during dexamethasone treatment. The expression of TIMP-2 was decreased both during immobilization and dexamethasone treatment. Decreased gene expression and increased degradation caused decreased concentration of type IV collagen, suggesting net degradation of type IV collagen during immobilization. While the gene expression and degradation were decreased during dexamethasone treatment, the amount of type IV collagen was not changed. Dexamethasone thus seemed to slow down the turnover of type IV collagen. Decreased mRNA levels of collagens and prolyl 4-hydroxylase suggest decreased biosynthesis of collagens during immobilization. The mRNA levels of collagens I, III and IV were increased in polyneuropathy and polymyositis. The concentration and staining intensity of type IV collagen was increased in polyneuropathy, as was also the quantity and staining intensity of (pro)MMP-9. The results suggest accumulation of type IV collagen in the basement membranes of muscle cells and capillaries in polyneuropathy muscles. Lengthened position during immobilization partly prevented the atrophy and changes in collagen metabolism in plantarflexors. Endurance running was effective in preventing muscle atrophy during dexamethasone treatment, but exercise did however fail to prevent the changes observed in type IV collagen synthesis and degradation.

Abstract Sepsis is a major challenge for healing responses maintaining homeostasis. Coagulation and inflammation are activated at the whole-body level, even in undamaged tissues. Despite constantly growing knowledge and advances in care, high mortality in severe sepsis remains. It was hypothesised that tissue regeneration processes may also be altered in severe sepsis. The study population consisted of 44 patients with severe sepsis and 15 healthy controls. Serum samples were obtained during ten days of severe sepsis and twice again, three months and six months later. Experimental suction blisters were performed twice during severe sepsis and at 3 and 6 months. Serum samples were obtained and suction blisters were induced once in controls. Biochemical analyses were performed to assess the level of procollagen I and III aminoterminal propeptides (PINP, PIIINP), reflecting the synthesis of corresponding collagens; in serum and suction blister fluid. In addition collagen I degradationproduct in serum was measured. Physiological measurements of transepidermal water loss and blood flow were done in order to evaluate the re-epithelisation rate and blood flow in an experimental wound. Levels of matrix metalloproteinases (MMPs) 2, 8 and 9 were measured from serum and suction blister fluid. Decrease in water evaporation from an experimental blister wound was slower in sepsis than in controls. On the fourth day the sepsis patients had higher blood flow in the blister wound than the controls (both in the healing wound and in the newly induced wound). The procollagen III aminoterminal propeptide (PIIINP) levels were increased in serum in severe sepsis, whereas procollagen I aminoterminal propeptide (PINP) levels were not, making up a pronounced PIIINP/PINP ratio. PIIINP and PINP levels were associated with disease severity and outcome. In addition, collagen I degradation measured with ICTP assay was increased in severe sepsis and PINP/ICTP ratio was lower. Furthermore, the overall protein concentration and PINP and PIIINP levels were low in suction blister fluid, which implies that the balance of the extracellular matrix consistence is disturbed in uninjured skin in severe sepsis. Then again in survivors the levels of PINP and PIIINP were up-regulated at three months but returned to normal by six months. MMP-9 levels in serum and skin blister fluid were lower in severe sepsis than in controls during the ten days studied. The MMP-2 levels were found to be increased both in serum and in skin blister fluid in severe sepsis in comparison to the controls and MMP-2 was associated with disease severity and outcome. MMP-8 was increased in serum and in skin blister fluid. In conclusion, the balance of collagen turnover is altered in severe sepsis in serum and skin and epidermal re-epithelisation is delayed. The levels of MMP-2 and MMP-8 are increased whereas levels of MMP-9 are depressed.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-15T13:55:03Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Lianne versão final.pdf: 1813010 bytes, checksum: 7347cf54c764e95be94ff262dc30ccb5 (MD5) / Made available in DSpace on 2016-04-15T13:55:03Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Lianne versão final.pdf: 1813010 bytes, checksum: 7347cf54c764e95be94ff262dc30ccb5 (MD5) Previous issue date: 2015-08-11 / CAPEs / O câncer do colo uterino é o quarto tipo de câncer mais comum entre as mulheres mundialmente, e o sétimo no geral. No Brasil, esta neoplasia é a terceira mais frequente no gênero feminino, com mais de 15 mil casos novos a cada ano. A infecção persistente pelo papilomavírus humano dos tipos de alto risco oncogênico está associada ao câncer cervical, porém uma pequena percentagem de mulheres infectadas por estes vírus desenvolve lesões pré-malignas que podem evoluir à invasão. Portanto, outros cofatores são necessários para a persistência viral que, após 2 anos sem intervenção, leva à expressão desregulada e concomitante das oncoproteínas transformantes E6 e E7. As enzimas degradadoras de matriz extracelular conhecidas como metaloproteinases da matriz tem sido extensamente estudadas devido ao seu papel na invasão, metástase, angiogênese e recidiva tumoral. Nas lesões cervicais, um aumento na expressão das metaloproteinases foi identificado, porém, seu papel na progressão das lesões pré-invasivas e sua interação com a infecção pelo papilomavírus ainda não está bem esclarecida. Neste intuito, o presente estudo visou avaliar, através de técnica imuno-histoquímica, a associação dos níveis de expressão das metaloproteinases da matriz 2 e 9 com os graus de lesões cervicais. Para isso, foram utilizadas amostras de biopsias parafinadas, diagnosticadas e arquivadas entre 2011 e 2015 no Laboratório de Anatomia Patológica do Hospital das Clínicas de Recife, Pernambuco, Brasil, incluindo 115 biopsias de lesões cervicais, obtidas por conização, bem como 14 casos de tecidos cervicais sem lesão. Os resultados obtidos neste trabalho demonstraram um aumento da expressão das metaloproteinases 2 e 9 nos casos de invasão em relação a condições pré-malignas, tanto no citoplasma quanto no núcleo de células epiteliais escamosas, sendo a intensidade da expressão nuclear das metaloproteinases estudadas mais significativa nas células cancerosas. Também foi observada diminuição da expressão das metaloproteinases 2 e 9 no citoplasma das células glandulares adjacentes na presença do carcinoma escamoso invasor, quando comparadas ao controle. Mais estudos precisam ser realizados para avaliar o valor prognóstico das metaloproteinases 2 e 9 nas condições pré-malignas e malignas do colo uterino. / The cervical cancer is the fourth most common cancer among women worldwide, and seventh overall. In Brazil, this cancer is the third most common in women, with more than 15,000 new cases each year. Persistent infection with human papillomavirus types of high oncogenic risk is associated with cervical cancer, but a small percentage of women infected by these viruses develop precancerous lesions that may progress to invasion. Therefore, other cofactors are required for viral persistence which, after 2 years without intervention, leads to unregulated and concomitant expression of transformants E6 and E7 oncoproteins. The extracellular matrix degrading enzymes known as matrix metalloproteinases has been extensively studied because of its role in invasion, metastasis, angiogenesis and tumor recurrence. In cervical lesions, an increase in the expression of metalloproteinases was identified, however, its role in the progression of pre-invasive lesions and their interaction with the papillomavirus infection is not well understood. To this end, the present study evaluated, through immunohistochemical technique, the association of the expression levels of matrix metalloproteinases 2 and 9 with grades of cervical lesions. For this, we used paraffined biopsy samples, diagnosed and filed between 2011 and 2015 at the Pathology Laboratory of the Hospital das Clínicas of Recife, Pernambuco, Brazil, including 115 biopsies of cervical lesions, obtained by conization, and 14 cases of tissues without cervical injury. The results of this study demonstrated an increased expression of metalloproteinases 2 and 9 in invasion compared to pre-malignant conditions, in both cytoplasm and nucleus of squamous epithelial cells, and a more significant intensity of the nuclear expression of metalloproteinases studied in cancer cells. It was also observed decreased expression of metalloproteinases 2 and 9 in the cytoplasm of adjacent glandular cells in the presence of invasive squamous cell carcinoma, when compared to control. More studies are needed to assess the prognostic value of metalloproteinases 2 and 9 in premalignant and malignant conditions of the cervix.

Orientador: Pedro Duarte Novaes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-27T00:17:50Z (GMT). No. of bitstreams: 1 Peroni_LeonardoVieira_M.pdf: 2591831 bytes, checksum: cb9ff6e79f251a6f1318c8e8daa209f7 (MD5) Previous issue date: 2015 / Resumo: A radioterapia causa efeitos adversos em grande parte dos tecidos nos quais é utilizada. Na cavidade oral, tem sido evidenciado que o periodonto é sensível à radiação em altas doses. Além de causar mudanças histofisiológicas, a radiação ionizante pode propiciar o desenvolvimento de alterações estruturais nos tecidos de suporte, incluindo osso e ligamento periodontal. As metaloproteinases de matriz (MMPs) estão presentes no ligamento periodontal e são enzimas que atuam na remodelação da matriz extracelular, degradando alguns de seus componentes. Acredita-se que sua expressão possa alterar a estrutura do ligamento periodontal. Sendo assim, neste trabalho teve-se como objetivo avaliar o efeito da radiação ionizante no ligamento periodontal do dente incisivo de rato, por meio da microscopia de polarização, do teste mecânico e da zimografia, estabelecendo possíveis correlações entre os testes. A amostra constituiu-se de 63 ratos machos da linhagem Wistar (Rattus norvegicus albinus) divididos em 3 grupos: o grupo controle, sendo o único grupo não irradiado (n=21), o grupo de animais mortos 14 dias após a irradiação (n=21) e grupo de animais mortos 28 dias após a irradiação (n=21). Os grupos irradiados foram submetido à sessão única de radioterapia com dose de 15. A análise dos resultados mostrou que o teste de força e a microscopia de polarização apresentaram diferença estatisticamente significante entre os grupos (p<0,001), o que não ocorreu para os resultados da zimografia. Os coeficientes de correlação de Pearson (R) detectaram forte correlação diretamente proporcional entre os testes de força e polarização (R=0,808), e moderada correlação inversamente proporcional entre a polarização e a zimografia de MMP-2 na forma ativa (R=-0,446). Portanto, concluiu-se que a radioterapia pode levar à diminuição da resistência à força de intrusão e provocar a desorganização do colágeno no ligamento periodontal; além disso, a expressão das metaloproteinases 2 e 9 não foi influenciada pela radiação ionizante e apenas a organização do colágeno apresentou correlação com a resistência das fibras do ligamento periodontal e com a expressão da metaloproteinase de matriz 2 na sua forma ativa / Abstract: Radiotherapy causes adverse effects in most tissues in which it is used. In the oral cavity, it has been shown that the periodontium is sensitive to high doses of radiation. Besides causing histophysiological changes, ionizing radiation can promote the development of structural changes in the supporting tissues, including bone and periodontal ligament. The matrix metalloproteinases (MMPs) are in the periodontal ligament and are enzymes that remodel extracellular matrix by degrading some of its components. Structure of periodontal ligament may be changed by its expression. Thus, this study aimed to evaluate the effect of ionizing radiation on the periodontal ligament of the rat incisor, by polarizing microscopy, strength and zymography test, establishing correlations among these tests. The sample consisted of 63 male Wistar rats (Rattus norvegicus albinus) divided into 3 groups: control group, the only group that wasn¿t irradiated (n=21); a group of animals killed 14 days after irradiation (n=21) and a group of animals killed 28 days after irradiation (n=21). Irradiated groups were submitted to a single session of radiotherapy with 15 Gy dose. The results showed that only the strength test and the polarization microscopy had a statistically significant difference between groups (p<0.001), differently from zimography results. The Pearson correlation coefficients (R) detected strong direct correlation between the strength tests and polarization (R= 0.808), and moderate inverse correlation between polarization and MMP-2 zymography in the active form (R= -0.446). Thereby, the conclusion was that radiotherapy can lead to a diminished resistance to the intrusion strength and to a disorganization of the periodontal¿s ligament collagen. The expression of metalloproteinases 2 and 9 was not affected by radiotherapy and only collagen organization had correlation with periodontal ligament fibers strength and expression of matrix metalloproteinase 2 in its active form / Mestrado / Radiologia Odontologica / Mestre em Radiologia Odontológica

Orientador: Paulo Sérgio Cerri / Resumo: A periodontite (DP) é uma doença imunoinflamatória que promove o recrutamento de células específicas que liberam mediadores, dentre eles interleucina-1 (IL-1), fator de necrose tumoral-alfa (TNF-α) e metaloproteinases da matriz (MMPs). Há evidências de que a diacereína, uma medicação anti-IL-1, reduz a produção de MMPs e TNF-α. O objetivo do presente estudo foi avaliar se a diacereína acelera a regressão da inflamação e reduz a perda óssea na DP induzida. No total, foram utilizados 66 ratos Holtzman distribuídos, aleatoriamente, nos diferentes grupos. Em 42 ratos, a DP foi induzida com inserção de uma ligadura no 1º molar superior direito por 7 dias. Após a indução, 12 animais foram sacrificados: 6 animais do grupo GP (grupo periodontite) e 6 animais do grupo controle (GC), usado como parâmetro da DP induzida. No 7º dia de indução da DP, a ligadura colocada em 36 ratos foi removida e iniciou-se o tratamento com 100 mg/kg de massa corpórea de diacereína (GPD) ou solução fisiológica (GPS) por gavagem durante 7, 15 e 30 dias. Após 24 horas da administração da última dose, 6 animais de cada grupo (GPD, GPS e GC) foram sacrificados. Após eutanásia, fragmentos de maxila com molares do lado direito foram removidos e logo imersos em solução de formaldeído 4%. Em seguida, os espécimes foram descalcificados em EDTA 7% e processados para inclusão em parafina. De cada fragmento, 5 cortes sagitais semi-seriados foram corados com hematoxilina e eosina (HE) para análises morfológica e quant... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Stimulation of β-adrenergic receptors (β-AR) induces apoptosis in adult rat ventricular myocytes (ARVMs) via the JNK-dependent activation of mitochondrial death pathway. Recently, we have shown that inhibition of matrix metalloproteinase-2 (MMP-2) inhibits β-AR-stimulated apoptosis and that the apoptotic effects of MMP-2 are possibly mediated via its interaction with β1 integrins. Herein we tested the hypothesis that MMP-2 impairs β1 integrin-mediated survival signals, such as activation of focal adhesion kinase (FAK), and activates the JNK-dependent mitochondrial death pathway. Inhibition of MMP-2 using SB3CT, a selective gelatinase inhibitor, significantly increased FAK phosphorylation (Tyr-397 and Tyr-576). TIMP-2, tissue inhibitor of MMP-2, produced a similar increase in FAK phosphorylation, whereas treatment of ARVMs with purified active MMP-2 significantly inhibited FAK phosphorylation. Inhibition of MMP-2 using SB3CT inhibited β-AR-stimulated activation of JNKs and levels of cytosolic cytochrome c. Treatment of ARVMs with purified MMP-2 increased cytosolic cytochrome c release. Furthermore, inhibition of MMP-2 using SB3CT and TIMP-2 attenuated β-AR-stimulated decreases in mitochondrial membrane potential. Overexpression of β1 integrins using adenoviruses expressing the human β1A-integrin decreased β-AR-stimulated cytochrome c release and apoptosis. Overexpression of β1 integrins also inhibited apoptosis induced by purified active MMP-2. These data suggest that MMP-2 interferes with the β1 integrin survival signals and activates JNK-dependent mitochondrial death pathway leading to apoptosis.

Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: The resin-dentin interface undergoes degradation by endogenous matrix metalloproteinases (MMPs) after adhesive procedures. Application of several MMP inhibitors such as chlorhexidine (CHX) to the demineralized collagen dentin matrix after acid-etching has been suggested to be a successful approach to prevent degradation of the hybrid layer. Further, nanotubes (HNT) have been used as a reservoir for encapsulation and controlled delivery for several therapeutic drugs with sustained release. Therefore, HNT can be encapsulated with CHX and incorporated into dentin adhesives for the possibility of enhancing the longevity and durability of the hybrid layer. Objective: To evaluate the effect of a CHX-encapsulated nanotube-modified primer/PR and adhesive/ADH on the microtensile resin bond strength (µTBS) to dentin. Materials and Methods: A commercial adhesive and its respective primer were modified by adding CHX-encapsulated nanotubes at two distinct concentrations (10 and 20 wt.%). The experimental adhesives were evaluated by degree of conversion (DC) and viscosity. Meanwhile, only viscosity was determined for the experimental primers. The prepared HNT-encapsulated with CHX (10 and 20 wt.%) powders were incorporated into the primer and/or adhesive according to the groups: ADH (control); HNT (control); 0.2% CHX; PR+CHX10%; PR+CHX20%; ADH+CHX10%; ADH+CHX20%. Human molars were selected and autoclaved; mid-coronal dentin surfaces were exposed for bonding purposes. Dentin surfaces were etched, followed by primer and adhesive application, and restored with a resin composite. After 24 hours, the teeth were sliced into beams for µTBS testing; beams collected for each tooth were equally assigned into two testing condition groups: 24 hours and 6 months. Microtensile bond strength was tested using a universal testing machine, and the types of failure were classified as adhesive, mixed, and cohesive failure. Data from DC and viscosity tests were analyzed using one-way ANOVA. Bond strength data were analyzed by pair-wise comparisons using the Sidak method to control the overall significance level at 5% for each aging time separately. Weibull-distribution survival analysis was used to compare the differences in the microtensile bond strength results among the groups after 24 hours and 6 months. Results and Conclusion: DC analysis revealed no significant differences among adhesive groups. However, ADH group had a significantly lower viscosity than modified adhesive groups, and a significantly higher viscosity than modified primer groups. Test results of stress value (MPa) by each group for each aging time revealed no significant differences among groups after 24 hours. However, after 6-month storage, modified primer groups (PR+CHX10%, PR+CHX20%) and 0.2%CHX group showed a significant difference in µTBS compared to control groups (ADH, HNT) and modified adhesive groups (ADH+CHX10%, ADH+CHX20%) in the same aging time testing (p < 0.05). When comparing the µTBS after 24 hours and 6 months, there were no significant differences among the groups except for the ADH+CHX20% group, for which MPa values were higher after 24 hours than 6 months (p = 0.0487). In conclusion, this study has demonstrated the great potential of modified dental primers with CHX-encapsulated nanotubes in preservation of the resin-dentin bond strength over a 6-month time period. Additionally, modification of dental primers and adhesives was a successful approach that didn’t compromise the characteristics or the mechanical properties of the materials and has a promising long-term effect on resin-dentin bond strength.

Matrix metalloproteinases (MMPs) are a family of zinc endopeptidases capable of digesting the extracellular matrix (ECM), which is essential for tissue structure and transmitting messages between cells. MMPs play an important role in cancer, controlling cell migration, proliferation, apoptosis, regulation of tumour expansion, angiogenesis and invasion. Previous research has indicated high expression of MT1-MMP in breast cancers suggesting a potential role in tumour progression. Our results confirm that 3D multicellular tumour spheroids (MCTS) using phenotype-specific breast cancer cell lines are a valuable experimental model of the tumour microenvironment. Optimisation of MCTS culture growth conditions using different breast cancer cell lines (MCF-7, T47D, MDA-MB-468 and MDA-MB-231) was performed. Unexpected detection of MT1-MMP in MCF-7 MCTS warranted further investigation. MT1-MMP expression in different micro-environmental conditions, including hypoxia and nutrient deprivation (serum-free induced autophagy) were measured in MCF-7 monolayer cultures and MCTS models using immunofluorescence (IF), immunohistochemistry (IHC) and western blot (WB). MT1-MMP expression was rapidly and irreversibly up-regulated in MCF-7 breast cancer cells under conditions of stress (hypoxia and autophagy) compared to normal conditions suggesting an important role of the culture environment on cells behaviour and protein expression. We employed isobaric tags for relative and absolute quantitation (iTRAQ) technology to correlate MT1-MMP increase with proteomic profiles in MCF-7 breast cancer cell grown under hypoxic, serum-free and 3D MCTS conditions. More than 3500 proteins were identified, which were clustered into groups based on response to unique or shared microenvironment changes. Hypoxic monolayer and spheroid cells exhibited changes in anaerobic metabolism and lipid synthesis, respectively, whereas autophagy resulted in up-regulation of cellular component disassembly. The result indicated multiple drivers of MT1-MMP expression in MCF-7 cells. / Al-Mstansiriya University, Iraq

No description available.

Bone Cancer Research Trust / The full text will be available at the end of the embargo: 6th October 2027