Дисертації з теми "Fibronectin Aggregation in Collagen"
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Reyes, Catherine Diane. "Collagen- and Fibronectin-Mimetic Integrin-Specific Surfaces That Promote Osseointegration." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11599.
Повний текст джерелаMillard, Christopher John. "Structural and functional characterisation of the collagen binding domain of fibronectin." Thesis, University of Oxford, 2007. http://ora.ox.ac.uk/objects/uuid:af0ec9b5-8789-498e-a1b7-5887ca1ad03f.
Повний текст джерелаAsadishekari, Maryam. "Design and Engineering of 3D Collagen-Fibronectin Scaffolds for Wound Healing and Cancer Research." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38378.
Повний текст джерелаStanton, Heather. "The role of matrix metalloproteinases in cell-matrix interactions." Thesis, Open University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284376.
Повний текст джерелаStupack, Dwayne G. P. "Utilization and regulation of integrins by lymphoid cells to adhere to fibronectin and collagen." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq23671.pdf.
Повний текст джерелаVäisänen, M. R. (Marja-Riitta). "Type XIII collagen:characterization of ectodomain shedding and its biological implications in mammalian cells, characterization of type XIII collagen expression in human cancers." Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:9514279085.
Повний текст джерелаLi, Chuen-wai, and 李鑽偉. "Dynamic compression and exogenous fibronectin regulates cell-matrix adhesions and intracellular signaling proteins of human mesenchymal stem cells in 3D collagen environment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/197553.
Повний текст джерелаpublished_or_final_version
Mechanical Engineering
Doctoral
Doctor of Philosophy
Iskender, Banu. "Investigating the effects of extracellular matrix molecules on human embryonic stem cells." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/investigating-the-effects-of-extracellular-matrix-molecules-on-human-embryonic-stem-cells(e6b6df88-645a-4516-92da-63b3efee3cdb).html.
Повний текст джерелаLinnola, R. (Reijo). "The sandwich theory:a bioactivity based explanation for posterior capsule opacification after cataract surgery with intraocular lens implantation." Doctoral thesis, University of Oulu, 2001. http://urn.fi/urn:isbn:9514259793.
Повний текст джерелаHuynh, Khon Verfasser], Rüdiger E. [Akademischer Betreuer] Scharf та Dieter [Akademischer Betreuer] [Willbold. "Role of fibronectin in platelet adhesion and aggregation: impact of biomechanics and β3 integrin on fibrillogenesis / Khon Huynh. Gutachter: Rüdiger E. Scharf ; Dieter Willbold". Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2012. http://d-nb.info/1029350108/34.
Повний текст джерелаShorikova, D. V. "The collagen-induced platelet aggregation and artery status in patients with arterial hypertension and heart failure with preserved ejection fraction." Thesis, БДМУ, 2021. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/18601.
Повний текст джерелаLidén, Åsa. "Integrin αVβ3-Directed Contraction by Connective Tissue Cells : Role in Control of Interstitial Fluid Pressure and Modulation by Bacterial Proteins". Doctoral thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6601.
Повний текст джерелаThis thesis aimed at studying mechanisms involved in control of tissue fluid homeostasis during inflammation.
The interstitial fluid pressure (PIF) is of importance for control of tissue fluid balance. A lowering of PIF in vivo will result in a transport of fluid from the circulation into the tissue, leading to edema. Loose connective tissues that surround blood vessels have an intrinsic ability to take up fluid and swell. The connective tissue cells exert a tension on the fibrous network of the tissues, thereby preventing the tissues from swelling. Under normal homeostasis, the interactions between the cells and the fibrous network are mediated by β1 integrins. Connective tissue cells are in this way actively controlling PIF.
Here we show a previously unrecognized function for the integrin αVβ3, namely in the control of PIF. During inflammation the β1 integrin function is disturbed and the connective tissue cells release their tension on the fibrous network resulting in a lowering of PIF. Such a lowering can be restored by platelet-derived growth factor (PDGF) -BB. We demonstrated that PDGF-BB restored PIF through a mechanism that was dependent on integrin αVβ3. This was shown by the inability of PDGF-BB to restore a lowered PIF in the presence of anti-integrin β3 IgG or a peptide inhibitor of integrin αVβ3. PDGF-BB was in addition unable to normalize a lowered PIF in β3 null mice. Furthermore, we demonstrated that extracellular proteins from Streptococcus equi modulated αVβ3-mediated collagen gel contraction. Because of the established concordance between collagen gel contraction in vitro and control of PIF in vivo, a potential role for these proteins in control of tissue fluid homeostasis during inflammation could be assumed. Sepsis and septic shock are severe, and sometimes lethal, conditions. Knowledge of how bacterial components influence PIF and the mechanisms for tissue fluid control during inflammatory reactions is likely to be of clinical importance in treating sepsis and septic shock.
Souza, Sandro José de. "Interações macromoleculares na matriz extracelular. Uma abordagem bioquímica e filogenética." Universidade de São Paulo, 1993. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-30012018-164002/.
Повний текст джерелаThe study of extracellular matrix (ECM) macrointeractions was approached in three models: the collagen/collagenase interaction, the collagen/fibronectin interaction and the molecular evolution of the matrix metalloproteinase (MMP) family of enzymes. MMP is characterized by its remarkable specificity against ECM components. Interstitial collagenases, the best studied members, attack interstitial collagens at a unique site producing two fragments. Using the complementary hydropathy hypothesis that states that peptides encoded by complementary nucleotide sequence can interact one to another, it was possible to characterize the sequence SQNPVQP (in fibroblast collagenase) or SSNPIQP (in neutrophil collagenase) as important in the interaction of the respective enzymes with collagen. The fact that fibronectin, another ECM component, binds at the same domain on collagen that is cleaved by collagenases arose the possibility of using the same approach (complementary hydropathy) in the study of collagen/fibronectin interaction. It was possible to characterize the fibronectin sequence TNEGVMY as important in the interaction with collagen. Adjacent to this site, there is a sequence (AAHEEIC) that shows an homology to the zinc-binding site present in several MMP. Therefore, zinc could be a modulator the collagen/fibronectin interaction. Finnaly, some phylogenetic aspects of the MMP family were studied. It was characterized a phylogenetic relationship between the catalytic core of MMP and the corresponding domain in Serratia protease and protease B from E. chrysanthemi, members of the same family of bacterial metalloproteinases. The catalytic activity of MMP can have evolved from the bacterial metaloproteinases whereas the substrate specificity is an acquisition of eukaryotic MMP
Marin, Paya Juan Carlos. "3D Culture o Multiple Myeloma Cell Line Using Microgel Environments." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/167427.
Повний текст джерела[CA] El mieloma múltiple és una neoplàsia hematològica caracteritzada per una expansió descontrolada de cèl·lules plasmàtiques monoclonals (mPCs) en medul·la òssia que produeixen, en la majoria dels casos, un component monoclonal secretat en el sèrum i/o en orina. En l'actualitat, es continua considerant una malaltia incurable, amb la constant aparició de recaigudes en els pacients. Una de les causes que condicionen aquesta situació, radica en la generació de resistència enfront de fàrmacs per part de les mPCs. Aquest mecanisme de resistència a fàrmacs (DR) s'ha vist que no sols depèn de factors intracel·lulars, sinó que la mateixa interacció de les mPCs amb el microambient medul·lar juga un paper fonamental per a la seua supervivència, creixement i desenvolupament de DR. Entre els components del microambient tumoral, destaca l'adhesió de les mPCs a components de la matriu extracel·lular (ECM) que s'ha vist relacionada amb la generació de DR. Per aquest motiu, el desenvolupament d'aquesta tesi doctoral va consistir en l'elaboració i validació d'una plataforma de cultiu 3D basada en la síntesi d'un microgel. Aquest sistema estarà constituït per microesferes funcionalitzades amb components de l'ECM com són la fibronectina (FN), col·lagen tipus I (COL), heparina (Hep), heparan sulfat (HS) i àcid hialurònic (HA), generant un entorn 3D biomimètic amb la capacitat de poder analitzar la resposta cel·lular desencadenada per la interacció de les mPCs amb els components de la ECM, així com la DR generada per l'adhesió de les mPCs a aquestes biomolècules. El primer estudi va consistir en la realització i posada a punt de diversos protocols per a la síntesi de diferents microgels; un primer sistema es va produir mitjançant la polimerització per via radical en bloc de copolímers de poliacrilat d'etil (EA) i polimetacrilat d'etil (EMA), o bé per EA, EMA i àcid acrílic (AAc). Mitjançant una emulsió del tipus oli en aigua es va aconseguir produir amb aquests copolímers, microesferes d'una grandària pròxima al de les mPCs. Un segon sistema es va basar en microesferes d'alginat. Aquestes microesferes es van obtenir en un dispositiu de microfluidica produint-se la gelificació externa de les microgotes amb la incorporació d'ions de calci aconseguint microesferes d'una grandària mitjana de 177 ¿m. A causa de la gran varietat de microesferes sintetitzades amb diferents grups químics en les seues superfícies, es va aconseguir establir protocols de funcionalització similars als establerts en la literatura, tenint en compte l'estabilitat de la biomolècula al llarg del temps del cultiu cel·lular. Aquest enfocament va permetre la funcionalització amb una gran varietat de biomolècules disposant així de microgels funcionalitzats amb FN, COL, Hep, HS y HA. Una vegada desenvolupats els microgels, en un segon estudi es va procedir a avaluar la resposta cel·lular en un entorn 3D basat en microgel, valorant la interacció amb els components de l'ECM. Entre els resultats observats es va poder determinar com la grandària de les microesferes afecta el creixement cel·lular fins i tot en absència de qualsevol funcionalització. Amb els microgels constituïts per microesferes d'una grandària pròxima al de les mPCs es va obtenir un major creixement cel·lular que amb els microgels formats per partícules de major grandària, i en tots dos el creixement va ser superior al del cultiu en suspensió. Es planteja la hipòtesi que la presència de les microesferes afavoreix en gran manera que es produïsca un major contacte cèl·lula-cèl·lula que es veu incrementat com més gran és la superfície específica del microgel. Entre els components de l'ECM estudiats, mentre que el COL no genera cap resposta cel·lular diferent del control (microgel no funcionalitzat), l'HA afavoreix la proliferació cel·lular. L'adhesió de les mPCs a la FN condiciona el bloqueig de les cèl·lules en la fase G0-G1 del cic
[EN] Multiple myeloma is a haematological neoplasm characterized by an uncontrolled expansion of monoclonal plasma cells (mPCs) in bone marrow that produce, in most cases, a monoclonal component secreted in serum and/or urine. At present, it is still considered an incurable disease with the constant appearance of relapses in patients. One of the causes that condition this situation lies in the generation of drug resistance by the mPCs. This mechanism of drug resistance (DR) has been seen to depend not only on intracellular factors, but the very interaction of mPCs with the medullary microenvironment plays a fundamental role in their survival, growth and development of DR. Among the components of the tumor microenvironment, the adhesion of the mPCs to components of the extracellular matrix (ECM) stands out, which has been related to the generation of DR. For this reason, the development of this doctoral thesis consisted in the elaboration and validation of a 3D culture platform based on the synthesis of a microgel. This system will be made up of micropsheres functionalized with the components of the ECM such as fibronectin (FN), collagen type I (COL), heparin (Hep), heparan sulphate (HS) and hyaluronic acid (HA), generating a 3D biomimetic environment with the ability to analyse the cellular response triggered by the interaction of mPCs with the ECM components, as well as the DR generated by the adhesion of the mPCs to these biomolecules. The first study consisted in the realization and development of several protocols for the synthesis of different microgels. A first system was produced by the radical block polymerization of polyethylene acrylate (EA) and polymethacrylate (EMA) co-polymers or by EA, EMA and acrylic acid (AAc). By means of an oil-in-water emulsion technique, it was possible to produce, with these copolymers, microspheres of a size close to that of the mPCs. A second system was based on alginate microspheres. These microspheres were obtained in a microfluidic device producing the external gelification of the micro-drops with the incorporation of calcium ions, obtaining microspheres with an average size of 177 µm. Due to the great variety of microspheres synthesized with different chemical groups on their surfaces, it was possible to establish functionalization protocols similar to those established in the literature, taking into account the stability of the biomolecule along with the time of cell culture. This approach allowed for functionalization with a great variety of biomolecules, having in this way functionalized microgels with FN, COL, Hep, HS and HA. Once the microgels were developed, a second study was carried out to evaluate the cell response in a 3D microgel-based environment, assessing the interaction with the components of the ECM. Among the results observed, it was possible to determine how the size of the microspheres affects cell growth even in the absence of any functionalization. With the microgels constituted by microspheres close to the size of the mPCs, a greater cellular growth was obtained than with the microgels formed by larger particles, and in both the growth was higher than in suspended culture. It is hypothesized that the presence of microspheres greatly favours a greater cell-cell contact, which is increased the larger the specific surface area of the microgel. Among the components of the ECM studied, while the COL does not generate any cellular response different from the control (non-functionalized microgel), HA favours cell proliferation. The adhesion of mPCs to FN conditions the blocking of cells in the G0-G1 phase of the cell cycle. This adhesion is mediated by the integrin ¿4ß1.
La presente tesis doctoral no se podría haber realizado sin la financiación del proyecto PROMETEO/2016/063, trabajo que también estuvo parcialmente financiado con fondos FEDER (CIBERONC (CB16/12/00284)). La iniciativa CIBER-BBN está financiada por el proyecto VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program. Las acciones CIBER están financiadas por el Instituto de Salud Carlos III con ayuda del Fondo Europeo de Desarrollo Regional.
Marin Paya, JC. (2021). 3D Culture o Multiple Myeloma Cell Line Using Microgel Environments [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/167427
TESIS
Vasilceac, Fernando Augusto. "Efeito do exercício resistido na cartilagem articular de modelo animal de osteoartrite." Universidade Federal de São Carlos, 2012. https://repositorio.ufscar.br/handle/ufscar/5287.
Повний текст джерелаFinanciadora de Estudos e Projetos
The aim of this study was to evaluate the effect of a strength exercise protocol on articular cartilage in animal model of osteoarthritis (OA). Thirty-six rats were divided in 6 groups: Control (C, n = 6), Osteoarthritis (OA, n = 6), Sham (S, n = 6), Control with exercise (E n = 6), Osteoarthritis with exercise (OAE, n = 6) and Sham with exercise (SE, n = 6). The animal model of osteoarthritis was anterior cruciate ligament transection (ACLT) in rats. After 2 weeks of ACLT, groups E, OAE and SE started the strength exercise protocol, three times a week for 8 weeks. We used the Mankin Histologic Grading System, measured the density of chondrocytes, the density of collagen fibers and the expression of collagen type II, chondroitin sulfate and fibronectin. The groups subjected to strength exercise protocol, OAE and SE, had lower values for the Mankin score, chondrocyte density and fibronectin expression and higher values for collagen fibers density, type II collagen expression and chondroitin sulfate expression when compared with OA and S, respectively. Group E was different from group C only in chondrocyte density and fibronectin expression. Therefore, strength exercise changes the content and expression of different articular cartilage constituent, having influence on our animal model of osteoarthritis and provides benefits to the cartilaginous tissue.
O objetivo desse estudo foi avaliar o efeito de um protocolo de exercício resistido na cartilagem articular de modelo animal de osteoartrite (OA). Trinta e seis ratos foram divididos em 6 grupos: Controle (C), Osteoartrite (OA); Sham (S), Exercício (E), Osteoartrite e Exercício (OAE), Sham e Exercício (SE). Os grupos OA, OAE, S e SE foram submetidos à transecção cirúrgica do ligamento cruzado anterior (LCA) do joelho esquerdo, sendo que somente os grupos OA e OAE tiveram o LCA seccionado. Após 2 semanas da cirurgia, os grupos E, OAE e SE iniciaram o protocolo de exercício resistido, 3 vezes por semana, durante 8 semanas. Foi aplicado o sistema de graduação histológica de Mankin, mensurado a densidade de condrócitos, a densidade de fibras colágenas e a expressão de colágeno tipo II, sulfato de condroitina e fibronectina. Os grupos submetidos ao protocolo de exercício resistido, OAE e SE, apresentaram menores valores para o sistema de graduação de Mankin, densidade de condrócitos e expressão de fibronectina e maiores valores para densidade de fibras colágenas, expressão de colágeno tipo II e sulfato de condroitina quando comparados aos grupos OA e S, respectivamente. O Grupo E apresentou diferença do grupo C somente na avaliação da densidade de condrócitos e na expressão de fibronectina. Portanto, o exercício resistido promove modificações no conteúdo e na expressão de diferentes constituintes da cartilagem articular, exercendo influência em nosso modelo de osteoartrite e trazendo benefícios para o tecido cartilaginoso.
Iselin, Jacob A. "Surface Modification of PLGA Electrospun Scaffolds for Wound Healing and Drug Delivery Applications." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1226012558.
Повний текст джерелаBecke, Tanja [Verfasser], Arndt F. [Akademischer Betreuer] Schilling, Arndt F. [Gutachter] Schilling, and Matthias [Gutachter] Rief. "Streptococcus pneumoniae TIGR4 pilus-1 biomechanical aspects of adhesion during interaction with host extracellular matrix proteins fibronectin and collagen I / Tanja Becke ; Gutachter: Arndt F. Schilling, Matthias Rief ; Betreuer: Arndt F. Schilling." München : Universitätsbibliothek der TU München, 2019. http://d-nb.info/1194162657/34.
Повний текст джерелаMoody, Hayley Ruscoe. "Feasibility of ranking articular cartilage conditions with non-destructive near-infrared spectroscopy with extension to the Mankin grading system." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/62760/1/Hayley_Moody_Thesis.pdf.
Повний текст джерелаSouleyreau, Wilfried. "Identification de nouveaux facteurs pronostiques et de nouvelles cibles thérapeutiques potentielles dans le cancer du rein." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0422/document.
Повний текст джерелаKidney cancer is one of the 10 commonest human cancers. To date, no biomolecular markers are available in this type of cancer, and in the case of metastatic cancer, the therapeutic arsenal is still inefficient. The different processes involved in cancer progression are still poorly understood. Understanding those processes could highlight new therapeutic targets, and new prognostic or diagnostic biomolecular markers of this disease. For a first project, a new innovative model has been generated from a murine RCC cell line as a tool to understand cancer progression mechanisms and to identify new therapeutic target and new biomolecular markers in kidney cancer. This model of sequential reimplantation of cancer cells isolated from primary tumours or metastases allowed us to generate different cell lines showing increased aggressiveness after passages. Using a systems biology strategy, this model will allow us to identify new potential therapeutic targets and new biomolecular markers in RCC. Interleukin-34 is an example of an already selected target, showing the power of the model generated. For a second project, the role of some members of extracellular matrix (collagen type I, fibronectin, matrigel).was studied using this same murine RCC cell line. This study demonstrated the potential pro-invasive and pro-metastatic roles of collagen type I deposition in tumors. Collagen-activated receptors are proposed as mediators of the effect induced by collagen type I in this model. Those two projects have and will continue to contribute to a better understanding of cancer progression mechanisms, and will bring out new biomolecular markers and new therapeutic targets
Renner, Adriana Frias. "Resposta do condrócito, proteoglicana, colágeno e fibronectina da cartilagem articular, após aplicação de um protocolo de imobilização, alongamento e remobilização articular." Universidade Federal de São Carlos, 2010. https://repositorio.ufscar.br/handle/ufscar/5116.
Повний текст джерелаUniversidade Federal de Sao Carlos
The function of articular cartilage depends on the chondrocytes and on the components of the extracellular matrix, which in turn may be regulated by mechanical stimuli. Thus, changes in load support may affect its composition or its structure and interfere with their functional ability to sustain and distribute loads and minimize the stresses of contact. Thus, investigations of articular cartilage components, such as chondrocyte and or matrix components are essential for prevention and treatment of arthritic disease. A greater understanding of the relationship of use / disuse and degeneration as well as the consequences of situations such as shear stress, static load or unloading can generate in this tissue. The aim of this study was to evaluate the response of chondrocytes, proteoglycan, collagen and fibronectin in articular cartilage after application of a protocol of immobilization, stretching and joint remobilization. Material and Methods: We used 36 animals divided into six groups (n = 6): immobilized (I), immobilized and stretched seven days per week (IS7), immobilized and stretched three days per week (IS3), stretched seven days per week (S7), stretched three days per week (S3) and control (C). Groups I, IS3 and AS7 underwent four weeks of immobilization of the left hind limbs. Groups IS7 and IS3, after immobilization, were subjected to three weeks of the posterior muscle stretching of the left hind leg daily or three times per week, respectively. The S3 and S7 groups remained free in the cage for 4 weeks and subsequently underwent three weeks of posterior muscle stretching of the left hind limb daily or three times per week, respectively. After these procedures, the left ankle were collected, decalcified, processed in paraffin and stained with H&E, Safranin-O, Picrossiruius Red and immunostained with fibronectin and chondroitin sulfate 4 for further analysis. Two observers evaluated parameters such as chondrocyte cloning, loss of proteoglycan content, thin and thick fibrils collagen content, intensity of staining for fibronectin and chondroitin sulfate 4. For statistical analysis we used the following tests: Kruskal Wallis and post hoc Newman Keuls: cloning and the proteoglycan content of the different groups); Duncan multiple comparison: morphometric evaluation of cellularity; ANOVA and post hoc Tukey: proportion of thin and thick fibrils of collagen. For analysis of the immunohistochemistry reactions of fibronectin and chondroitin sulfate 4 it was used nonparametric test Kruscal Wallis and post hoc Newman Keuls. In all tests the significance level was p ≤ 0.05. Results: With respect to the cellularity IS7 group showed significant increase in cellularity compared to groups I and C. The IS3 group also showed significant celullar change with the formation of chondrocyte cloning compared to groups S7, S3 and C. The most significant loss of proteoglycan was in IS7 group compared to all other groups. The I group also lost significantly more proteoglycan than the others, except for IS7 group. With respect to collagen fibrils was observed that immobilization (I) significantly reduced the thin fibrils in relation to groups IS3, S7, S3 and C. The quantity of thick fibrils was influenced by mechanical overload, as there was a significant decrease of it in all groups compared to control. With respect to the findings of the fibronectin, the groups immobilized and stretched (IS3 and IS7) had significantly higher intensity staining of fibronectin than other groups. There was no statistical difference of chondroitin sulfate 4 immunostaining among the different groups. Conclusion: The protocols of muscle stretching after immobilization, applied on alternate days and daily provoked distinct adaptive responses in articular cartilage. The immobilization stimulated tissue atrophy that when stimulated by muscle stretching on alternate days, kept some matrix components, such as fine fibrils of collagen and proteoglycan, unlike the protocol used daily. Thus we can conclude that muscle stretching applied in previously immobilized joints should be applied with caution, on alternate days of mechanical stimulation.
A função da cartilagem articular é dependente do condrócito e dos componentes de sua matriz extracelular, que por sua vez, podem ser regulados por estímulos mecânicos. Assim, alterações no suporte de carga podem afetar sua composição ou sua estrutura e interferir na sua capacidade funcional de sustentar e distribuir cargas e minimizar os estresses de contato. Desta forma, investigações dos componentes da cartilagem articular, como o condrócito e ou componentes da matriz são essenciais para prevenção e tratamento de doenças articulares. É necessário um maior entendimento das relações de uso/desuso e degeneração, assim como das conseqüências que situações como estresse de cisalhamento, carga estática prolongada ou ausência de carga possam gerar neste tecido. O objetivo do presente estudo foi avaliar a resposta do condrócito, proteoglicana, colágeno e fibronectina da cartilagem articular, após aplicação de um protocolo de imobilização, alongamento e remobilização articular. Material e Métodos: foram utilizados 36 animais divididos em 6 grupos (n=6): imobilizado (I), imobilizado e alongado 7 dias por semana (IA7), imobilizado e alongado 3 dias por semana (IA3), alongado 7 dias por semana (A7), alongado 3 dias por semana (A3), e controle (C). Os grupos I, IA7 e IA3 foram submetidos a 4 semanas de imobilização da pata traseira esquerda. Os grupos IA7 e IA3, após a imobilização, foram submetidos a 3 semanas de alongamento da musculatura posterior da pata traseira esquerda diariamente ou 3 vezes por semana, respectivamente. Os grupos A7 e A3 permaneceram livres na gaiola por 4 semanas e posteriormente foram submetidos a 3 semanas de alongamento da musculatura posterior da pata traseira esquerda diariamente ou em dias alternados, respectivamente. Após esses procedimentos, os tornozelos esquerdos foram coletados, descalcificados, processados em parafina e corados com H&E, Safranina, Picrossiruius Red e imunomarcados para fibronectina e sulfato de condroitina 4 para posterior análise. Foram avaliados por dois observadores parâmetros como: celularidade, contagem de clones, perda de proteoglicanos, conteúdo de fibrilas finas e grossas de colágeno e expressão de fibronectina e sulfato de condroitina 4. Para comparação destes parâmetros entre os diferentes grupos foram utilizados os seguintes testes estatísticos: Kruskal Wallis com post hoc Newman Keuls: formação de clones e conteúdo de proteoglicanas; Comparações múltiplas de Duncan: avaliação morfométrica de celularidade e Anova com post hoc de Tukey: proporção das fibrilas finas e grossas de colágeno. Para análise das reações de imunohistoquímica para fibronectina e sulfato de condroitina 4 foi utilizado o teste não paramétrico de Kruscal Wallis e post hoc Newman Keuls. Em todos os testes o nível de significância foi de p≤0,05. Resultados: com relação a celularidade o grupo IA7 apresentou aumento significativo da celularidade em relação aos grupos I e C. O grupo IA3 também apresentou alteração celular significativa com formação de clones em relação aos grupos A7, A3 e C. A maior perda significativa de proteoglicanas foi do grupo IA7 em relação a todos os outros grupos. O grupo I também perdeu significativamente mais proteoglicanas que os demais, somente não com relação ao grupo IA7. Com relação às fibrilas colágenas foi observado que a imobilização (I) reduziu significativamente as fibrilas finas em relação aos grupos IA3, A7, A3 e C. Já a quantidade de fibrilas grossas sofreu influência da sobrecarga mecânica, pois que houve diminuição significativa das mesmas em todos os grupos em relação ao controle. Com relação aos achados de fibronectina, os grupos imobilizados e alongados (IA7 e IA3) apresentaram significativamente maior intensidade de marcação desta que os outros grupos. Não houve diferença estatística das imunomarcações para sulfato de condroitina 4 entre os diferentes grupos. Conclusão: Os protocolos de alongamento muscular, após imobilização, realizados em dias alternados e diariamente, provocaram respostas adaptativas distintas na cartilagem articular. A imobilização desencadeou um quadro de atrofia tecidual que quando estimulada por alongamentos musculares em dias alternados, manteve alguns componentes da matriz, como fibrilas finas de colágeno e proteoglicana. Esta resposta foi agravada quando o mesmo protocolo foi aplicado diariamente. Desta forma, podemos concluir que o alongamento muscular aplicado em articulações previamente imobilizadas deve ser aplicado com cautela, respeitando períodos intercalados de estímulo mecânico.
Ivanoff, Jyrki. "Migration on extracellular matrix surface and infiltration into matrix - two distinguishable activities of human T cells." Doctoral thesis, Umeå University, Clinical Microbiology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-159.
Повний текст джерелаMigration 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.
Robert, Joe͏̈lle. "Influence de divers constituants de la matrice extracellulaire sur le comportement de cellules dermiques d'embryon de poulet cultivées in vitro." Grenoble 1, 1988. http://www.theses.fr/1988GRE10110.
Повний текст джерелаCornet, Sylvie. "Evolution de la lame basale glomerulaire au cours de la nephrogenese et de la senescence, chez le rat." Paris 6, 1988. http://www.theses.fr/1988PA066166.
Повний текст джерелаSantoro, Marcelo Larami. "Contribuição à investigação das alterações hemostáticas induzidas pelo veneno da serpente Bothrops jararaca em coelhos: estudo das glicoproteínas da membrana, função, secreção e sobrevivência plaquetárias." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-17062002-133506/.
Повний текст джерелаIn spite of being well established that Bothrops jararaca snake venom causes blood coagulation and fibrinolysis disturbances in patients, scant information about blood platelet disorders during envenomation is available. In recent investigations, thrombocytopenia, platelet aggregation disturbances and decreased numbers of platelet dense bodies were observed following venom administration, suggesting that circulating platelets had been activated. In order to prove this hypothesis and to gain a better characterization of the in vivo role of this venom on platelets, an experimental model of B. jararaca envenomation was utilized. Rabbits were injected i.v. either with B. jararaca venom (60 µg/kg) (experimental group) or saline (control group). Previously to saline or venom administration, rabbit platelets were labeled ex vivo with NHS-biotin. To evaluate platelet disturbances, blood samples were collected consecutively, at time intervals that varied from 1 to 144 hours after venom or saline administration. During envenomation, there were thrombocytopenia, hypofibrinogenemia, elevation of von Willebrand factor plasma levels, reduced botrocetin- and collagen-induced platelet aggregation in whole blood, and decreased ATP secretion. However, plasma levels of platelet factor 4, a specific marker of in vivo platelet activation, and intraplatelet serotonin levels remained constant. By flow cytometry, a significant decrease on the expression of GPIIb-IIIa epitope recognized by P2 monoclonal antibody was observed; however, this was not observed when polyclonal antibodies were employed. Fibrinogen or fibrin(ogen) degradation product (FDP) expression on platelet surface showed no significant alteration. Nonetheless, significant elevations of platelet P-selectin, a receptor whose expression is indicative of platelet activation, and of ligand-induced binding sites (LIBS1) of GPIIIa were noted. The percentage of circulating reticulated platelets, as well as platelet survival times, were not statistically different between the two groups. Histopathological and immunohistochemical analyses of rabbit organs demonstrated that circulating platelets were sequestered among fibrin deposits in pulmonary capillaries. These results suggest that thrombin generated by procoagulating components of B. jararaca venom has an essential role in the pathogenesis of platelet and coagulation disorders in this experimental model. Increased expression of P-selectin in the experimental group proves the initial hypothesis that platelets of envenomed rabbits are indeed activated in the circulation. The data presented herein demonstrate definitively that decreased fibrinogen or increased FDP levels are not the primary cause of the platelet dysfunction observed in bothropic envenomation, but other substances seem to be responsible for it.
Shi, Yuei-Mei, and 徐月梅. "Characterization of fibronectin matrix assembly in MDCK cells cultured on dish, collagen gel-coated dish, on collagen gel and in collagen gel." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/70774338344772701567.
Повний текст джерела國立成功大學
生理學研究所
89
The interactions of extracellular matrix (ECM) and cell play important roles in cell proliferation, differentiation, and survival. Previous studies in our laboratory showed that MDCK cells lost the microvilli when cultured on type I collagen gel, whereas they formed cystic structures and exhibited microvilli formation on apical membrane when cultured in type I collagen gel. Interestingly, there was a thick layer of fibronectin deposited around MDCK cysts. We hypothesized that the property of fibronectin matrix might affect collagen fibril-induced loss of microvilli in MDCK cells. In this study, we found that total content of fibronectin and the level of assembled fibronectin matrix were enhanced in cells cultured on collagen gel-coated dish than on normal dish within 24 h. The nature of fibronectin was assessed by the treatment of the cells with collagenase. This treatment abolished collagen gel-coating induced increase in fibronectin content within one day. However, cells cultured on collagen gel-coated dish and in collagen gel exhibited markedly higher levels of collagenase-resistant fibronectin than cells cultured on normal dish and collagen gel within 2-6 days. We also detected significant increase of degraded fibronectin fragments in cells cultured on collagen gel-coated dish and in collagen gel, but the degree of fibronectin degradation seemed to be higher in the former than the latter conditions. Treatment of different fibronectin fragments also induced partial loss of microvilli in MDCK cells cultured on normal dish. In addition, rhodostomin induced disappearance of microvilli, but did not alter total content or assembled matrix of fibronectin in MDCK cells. Taken together, assembled and collagenase-resistant fibronectin matrix should be important for prevention of collagen gel-induced loss of microvilli.
Guan-XianWu and 吳冠賢. "Collagen gel induces formation of aggregation in leiomyomal cell in vitro." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/94501256810161738853.
Повний текст джерела國立成功大學
生理學研究所
100
The maintenance of tissue integrity is mainly controlled by the environmental cues, such as chemical signals and physical inputs, i.e., tissue stiffness. However, by using in vitro culture technique, cells are always cultured on plastic dish which may not be relevent to the in vivo physical property of tissue. Recent studies have developed several hydrogel systems, such as collagen gel to mimic physiological stiffness of tissue. It has been shown that collagen gel induces three-dimensional tissue-like multicellular structures which are more relevent to in vivo system. Uterine leiomyoma is a benign tumor grown in myometrium. Smooth muscle cells that derived from leiomyomal form ball-like aggregates whereas normal myometrial cell does not, suggesting that the formation of aggregation is one the major characteristics of leiomyomal cell in vitro. While much effort has been focused on the soluble/genetic factors in the formation of ball-like aggregrates, little is known on ECM stiffness in the regulation of the ball-like aggregrates in leiomyomal cells. Thus, my project is to investigate the role of ECM stiffness in the regulation of ball-like aggregrates in leiomymal cells. First I investigated whether collagen gel culture system induces aggregations of leiomyomal cell. The results showed that leiomyomal cell formed more aggregates when cells were grown on collagen gel but not collagen-coated dish. To further investigate the degree of collagen rigidity affected formation of aggregates, I performed different collagen gels from different origins. The results showed that leiomyomal cell developed cell aggregates on softer collagen gel earlier than stiff one. Leiomyomal cell contracted and resulted in shrinkage of collagen gel, suggesting the involvement of cell contractility in leiomyomal cell aggregation on collagen gel. Pharmacologic inhibition of myosin-II related contractility inhibited the leiomyomal cell aggregation on collagen gel. These results suggest that physical property of substratum and cell contractility regulated formation of leiomyomal cell aggregation.
Chang, Juyn-Ming, та 張峻銘. "The effects of collagen mimetic peptides on the aggregation of Aβ(16-22)". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/4d5sw6.
Повний текст джерела國立清華大學
化學系
102
Abstract Alzheimer's disease ( AD ) is one of the most fatal neurodegenerative disease .The major pathogenesis of Alzheimer's disease ( AD ) is neurofibrillary tangles and enile plaques , and the aggregation of the A 40 plays a crucial role in the pathogenesis of the senile plaques of Alzheimer's disease (AD) . Although the amyloid -protein has been studied extensively , the mechanisms of A aggregation in brain remain unclear . In this study , we investigate the influence of the collagen related peptides on A aggregation. Here we chose the most important region of amyloid -protein responsible for aggregation , residues 16-22 (KLVFFAE) , as our study model . We incorporated the collagen sequence (POG)n into Aβ(16-22) and synthesized eight peptides: WT-A(16-22) , A(16-22)-(POG)6 , A(16-22)-(POG)7, A(16-22)-(POG)10 , (POG)7-A(16-22) and (POG)10-A(16-22).Two collagen peptides (POG)7 and (POG)10 were synthesized as the control peptides for comparison.We used fluorescence spectroscopy, TEM , CD , FT-IR and DLS to study whether the collagen sequence can inhibit A aggregation . CD measurements indicate that the Aβ(16-22) sequence at the N-terminus of (POG)n does not stabilize the triple-helical structure of collagen and such peptides have a weaker thermal stability than (POG)n .In contrast,when the Aβ(16-22) sequence is attached to the C-terminus of (POG)n, it can stablize the triple-helical structure of collagen. From aggregation studies, we found that the amyloid aggregation did not occur when (POG)7 was incorporated into A(16-22) but the aggregation was enhanced when (POG)10 incorporated into A(16-22).The mixing experiments indicate that (POG)7A cannot inhibit the aggregation of WT-A(16-22) while A(POG)6 and A(POG)7 can.The inhibition effect may not be due to the triple-helical structure of collagen but the PPⅡ structure.
Yeh, Kuo-Yi, and 葉國儀. "Catrolin, a Snake Venom Protein from Crotalus atrox, Inhibits Collagen-Induced Platelet Aggregation." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/16088176638713297228.
Повний текст джерелаCooper, Thomas. "Coating Collagen Modules with Fibronectin Increases in vivo HUVEC Survival and Vessel Formation through the Suppression of Apoptosis." Thesis, 2009. http://hdl.handle.net/1807/18244.
Повний текст джерелаMoore, Todd Robert. "Characterisation of the collagen binding domain of gelatinase A : involvement of specific residues in the fibronectin type II modules in substrate recognition." Thesis, 2001. http://hdl.handle.net/2429/11743.
Повний текст джерелаManganare, Marcos M. "Promoting Extracellular Matrix Crosslinking in Synthetic Hydrogels." 2015. https://scholarworks.umass.edu/masters_theses_2/285.
Повний текст джерелаAbdeldayum, Ali I. A., Mansour Youseffi, Farshid Sefat, Mohamed A. Genedy, Jamil M. M. Abdul, and F. Javid. "The effect of WIN55, 212-2 on protein S100, matrix metalloproteinase-2 and nitric oxide expression of chondrocyte monolayer." 2017. http://hdl.handle.net/10454/17016.
Повний текст джерелаStudies have been conducted to highlight the anti-inflammatory and immunosuppressive properties of synthetic cannabinoids as well as their potential for cartilage repair. Various wound healing techniques can be used to investigate the mechanisms of chondrocyte repair in monolayers or three dimensional tissues constructs. In this work the effect of WIN55, 212-2 (WIN-2) on nitric oxide (NO) and matrix metalloproteinase-2 (MMP-2) expressed by wounded chondrocyte monolayers was investigated. Moreover, expression of collagen type-I and type-II, fibronectin and S100 proteins were detected using immunofluorescence and quantitatively verified using ELISA based techniques following treatment with 1 μM and 2 μM of WIN-2. Treating chondrocytes with 1 μM of WIN-2 significantly increased expression of collagen type-II, fibronectin and S100, and significantly reduced collagen type-I expressions as compared to the control groups. On the other hand, both concentrations of WIN-2 significantly reduced the expression of the inflammation markers NO and MMP-2 in a dose dependent manner. These findings highlight the potential use of the synthetic cannabinoids for improving cartilage healing properties as well as acting as an anti-inflammatory agent which could be used to enhance tissue engineering protocols aimed at cartilage repair.
Volland, Marcel. "Effekte von Calcitriol auf die renale Fibrogenese." Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-000D-EFAC-E.
Повний текст джерела