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1
Getgood, Alan Martin John. „Articular cartilage tissue engineering“. Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608764.
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2
Gratz, Kenneth R. „Biomechanics of articular cartilage defects“. Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3284116.
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Thesis (Ph. D.)--University of California, San Diego, 2007.Title from first page of PDF file (viewed January 9, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
3
Arkill, Kenton Paul. „Mass transport in articular cartilage“. Thesis, University of Exeter, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421565.
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4
Burgin, Leanne Victoria. „Impact loading of articular cartilage“. Thesis, University of Aberdeen, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288339.
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Impact loads have been implicated in the initiation of secondary osteoarthritis but in the absence of defined injury this is difficult to rest rigorously. The response to controlled impacts of samples of cartilage and bone in isolation and together, may yield valuable insights into how tissue properties may influence degenerative changes associated with osteoarthritis. A rigid instrumented drop tower was constructed and interfaced to a LabVIEW software oscilloscope modified to capture and store data to disk. Controlled impact loads were applied to cores of articular cartilage, both isolated and in situ on the underlying bone or bonded to substrates of different material properties. Bovine tissue from the carpometacarpal joint and human cartilage from elderly femoral heads was used. The response of the samples was investigated in terms of a dynamic stiffness, energy absorbed and coefficient of restitution. In addition the quasistatic modulus was measured from compression tests in order to compare the values for the stiffness of cartilage and bone at different rates of stress and strain. Composition analysis was then performed on human cartilage samples to investigate if there was any correlation between the biochemical constituents and mechanical factors. The dynamic stiffness of the cartilage samples was governed by peak stress and did not show a high sensitivity to strain rate. Cartilage had good force attenuating properties in situ on bone and the substrates. The greater volume of the stiffer underlying substrate dominated the response of the composite samples. For the human cartilage samples the dynamic stiffness was most correlated to percentage collagen whereas the quasistatic modulus was most correlated with water content. Overall the biochemical composition was a poor predictor of stiffness which indicates the importance of interactions between the matrix constituents in the tissue response to an applied load.
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Rowles, Christopher. „Visualisation of Articular Cartilage Microstructure“. Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/52984.
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This thesis developed image processing techniques enabling the detection and segregation of biological three dimensional images into its component features based upon shape and relative size of the features detected. The work used articular cartilage images and separated fibrous components from the cells and background noise. Measurement of individual components and their recombination into a composite image are possible. Developed software was used to analyse the development of hyaline cartilage in developing sheep embryos.
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Girdler, N. M. „The role of mandibular condylar cartilage in articular cartilage repair“. Thesis, King's College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309110.
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7
Chan, Alex Dart Ming. „Neurogenic modulation of articular cartilage degeneration“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ41123.pdf.
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Covert, Rebeccah Jean. „Durability evaluation of articular cartilage prostheses“. Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/17596.
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Goldsmith, Andrew Alan John. „Biphasic modelling of synthetic articular cartilage“. Thesis, University of Bath, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321846.
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10
Ardill, Jennifer Maureen. „Optical measurement of articular cartilage roughness“. Thesis, Queen's University Belfast, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241325.
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11
Barton, Nicholas J. „Accurate assessment of articular cartilage roughness“. Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334495.
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12
Kerin, Alexander James. „The mechanical failure of articular cartilage“. Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265315.
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13
Eldridge, Suzanne. „Agrin contributes to articular cartilage homeostasis“. Thesis, Queen Mary, University of London, 2016. http://qmro.qmul.ac.uk/xmlui/handle/123456789/12812.
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Osteoarthritis is a leading cause of disability for which there is no cure. We have discovered that the multidomain signalling protein Agrin, most commonly known for its requirement at the neuromuscular junction, strongly promotes chondrocyte differentiation and cartilage formation in vivo. Agrin is expressed in normal cartilage but absent in osteoarthritis. In vitro, Agrin knockdown resulted in the downregulation of the cartilage transcription factor SOX9 and other cartilage-specific extracellular matrix molecules. Conversely, the addition of exogenous Agrin supported cartilage differentiation in vitro and ectopic cartilage formation in vivo. In contrast to other biological contexts where Agrin signalling requires the interaction with either LRP4 or α-dystroglycan, chondrocytes require the presence of both receptors. Our results identify Agrin as a novel potent anabolic growth factor with strong therapeutic potential in cartilage regeneration.
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Lin, John W. (John Wei-Chieh). „Electrokinetic evaluation of human articular cartilage“. Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36644.
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15
Stinn, Jennifer L. (Jennifer Leigh). „Inhibition of metalloproteinases in articular cartilage“. Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/38745.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Includes bibliographical references (leaves 70-74).
by Jennifer L. Stinn.
M.S.
16
Stadnik, Paulina. „Mechanically-regulated microRNAs in articular cartilage“. Thesis, Cardiff University, 2016. http://orca.cf.ac.uk/97563/.
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Introduction: The role of microRNAs (miRs) in articular cartilage is still not well established, however many studies have reported the differential expression of a number of miRs between healthy and osteoarthritic (OA) articular cartilage. These studies have focused on the OA pathology itself without considering the impact of mechanical load, which is one of the major risk factors implicated in the loss of cartilage integrity and the onset of OA development. Previous studies have already identified a number of mechanically-regulated miRs, therefore I hypothesised that (i) physiological and non-physiological magnitudes of compressive load differentially regulate the expression of mechano-sensitive miRs, and (ii) mechanically-regulated miRs differentially expressed in response to a non-physiological magnitude of load are implicated in the regulation of mechano-sensitive matrix molecule turnover and are involved in OA development. Results: Transcriptional assessment of selected mechanically-regulated matrix molecules demonstrated that loading regimes of 2.5MPa and 7MPa (1Hz, 15 minutes) induced homeostatic and catabolic responses at the gene level respectively, therefore they were selected to represent ‘physiological’ and ‘non-physiological’ magnitudes of loads which have the potential to induce biosynthetic and degradative protein responses if applied for prolonged periods of time. Next generation sequencing (NGS) of articular cartilage miRs libraries demonstrated that the alteration in expression of specific miRs occurs in a magnitude- and time-dependent manner. However, 24h post-load, according to the NGS data, seems to be the most appropriate to observe significant changes in miRs levels. Validation of a few miRs, important for cartilage integrity, at 24h post-load indicated up-regulation of miR-21-5p, miR-27a-5p, miR-221 and miR-222 and down-regulation of miR-483 in response to the ‘non-physiological’ 7MPa magnitude (1Hz, 15 minutes) whereas in explants subjected to a ‘physiological’ 2.5MPa magnitude (1Hz, 15 minutes) the level of these miRs remained unchanged. Identification of target genes of miR-21-5p, miR-221 and miR-222 performed by NGS of RNA extracted from primary articular chondrocytes transfected with specific miR inhibitors demonstrated a number of differentially expressed genes. qPCR validation of these potential miR target genes on RNA collected from cells transfected with functional miR-21-5p, miR-221 and miR-222 inhibitors or mimics identified TIMP-3 as a direct target of miR-21-5p, miR-221 and miR-222, whereas CPEB was targeted by miR-21-5p. Conclusion: This current study confirms the reported mechano-regulation of miR-221 and miR-222, and furthermore demonstrates the novel mechano-regulation of miR-21-5p, miR-27a-5p and miR-483 in cartilage explants. This work is the first to identify TIMP-3 as a target of miR-21-5p and miR-221/-222, and CPEB3 as a direct target of miR-21-5p in primary chondrocytes. An association between the identified differentially-regulated miRs in response to a non-physiological magnitude of load, with those that are expressed in OA cartilage and their regulatory effect on molecules important for cartilage integrity, described in this thesis may pioneer future studies aimed at identifying cartilage biomarkers of load-induced OA and provide therapeutic potential for OA treatment.
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Bliss, Cody Larry. „Sensate Scaffolds for Articular Cartilage Repair“. Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194815.
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Polymer scaffold use has become commonplace in tissue engineering strategies. Scaffolds provide sturdy interfaces that securely anchor tissue engineered constructs to their designated locations. Researchers have used scaffolds to provide support to developing tissues as well as a growth template to aid the development of the desired phenotypic structure. In addition to using scaffolds for their mechanical support, scaffolds can be used as a diagnostic tool by attaching sensors. Strain gauge sensors have been attached to scaffolds to monitor compression and elongation. These polybutylterphalate (PBT) scaffolds were used in a cartilage tissue-engineering project for femoral cartilage repair. The aim of this project was to measure native cartilage pressure in normal canine stifle joints using strain gauge scaffolds. By using pressure sensitive films to confirm joint surface pressures determined with strain gauge measurements, "sensate" scaffolds were created to be able to provide in vivo joint loading measurements. An understanding of the in vivo pressures in the menisco-femoral joint space will facilitate the development of tissue engineered cartilage by determining chondrocyte mechanical triggers as well as helping define reasonable expectations for engineered articular cartilage tissue that is required for successful cartilage repair.
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Andrade, Andre Luis Lugnani de. „Expressão do fator de transcrição HIF - 1'alfa' em condrocitos humanos cultivados em condições normais de oxigenio“. [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/309649.
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Orientador: Ibsen Bellini CoimbraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-07T22:55:15Z (GMT). No. of bitstreams: 1 Andrade_AndreLuisLugnanide_M.pdf: 2450375 bytes, checksum: f33edb219ba25e56f663f1256a99bbeb (MD5) Previous issue date: 2006
Resumo: Introdução: Os condrócitos da cartilagem articular vivem em um ambiente com baixa concentração de oxigênio. Nestas condições, a proteína do fator induzido por hipóxia (HIF-1a) mantém-se estável e ativa genes que são fundamentais na homeostase do oxigênio. A expressão do HIF-1a aumenta, em joelhos com osteoartrite (OA), principalmente nas áreas mais afetadas pela degeneração. Os condrócitos são capazes de produzir mediadores inflamatórios, como a interleucina-1 (IL-1) e o fator de necrose tumoral a (TNF-a), que estimulam a produção de prostaglandinas, metaloproteinases e óxido nítrico e relacionam-se com o início e com a progressão da osteoartrite. Os antiinflamatórios são drogas freqüentemente utilizadas no tratamento sintomático da OA. Material e Método: condrócitos humanos de joelhos osteoartríticos cultivados em suspensão e em condições normais de oxigênio foram divididos em quatro grupos: 1) controle, 2) estimulados com IL-1 ou TNF-a, 3) estimulados com meloxicam ou parecoxibe e 4) estimulados com meloxicam ou parecoxibe associados a IL-1 ou TNF-a. Os grupos foram submetidos à extração de RNA (ácido ribonucléico) e de proteína nuclear. O RNA foi convertido em cDNA, sendo então realizada a reação de PCR em tempo real para verificar a expressão do HIF-1a. As proteínas nucleares foram extraídas, quantificadas e analisadas pela técnica de Western Blotting. Resultados: Foi detectada a expressão de HIF-1a e cDNA de HIF-1a em todos os grupos de condrócitos cultivados em suspensão em tensões normais de oxigênio, não havendo diferenças significativas entre os grupos. Discussão: a meia-vida do HIF-1a é extremamente curta em normóxia e marcadamente prolongada em hipóxia, por isso muitos pesquisadores acreditam não ser possível a detecção da proteína do HIF-1a em condrócitos cultivados em condições normais de oxigênio. Neste estudo foi possível constatar a expressão do HIF-1a em normóxia, possivelmente devido ao modelo de cultura utilizado. O estímulo com IL-1, TNF-a e inibidores da COX-2 não alterou a expressão de HIF-1a. Condrócitos oriundos de articulações osteoartríticas avançadas poderiam apresentar resistência à ação das citocinas
Abstract: Introduction: The chondrocytes of joint surface live in low concentration of oxygen environment. In this condition, the hypoxia inducible factor 1 a (HIF-1a) becomes stable and regulates the expression of genes that are important for oxygen homeostasis. The expression of HIF-1a mRNA is augmented in chondrocytes from osteoarthritic knees, especially in more degenerated areas. Chondrocytes are capable of producing inflammatory mediators, such as interleukin 1 (IL-1) and tumoral necrosis factor a (TNF-a), that stimulate the production of prostaglandin, metalloproteinases and nitric oxide, correlated with the onset and progression of osteoarthritis. Antiinflammatory drugs are frequently used in the treatment of symptoms of osteoarthritis. Material e Methods: human chondrocytes from osteoarthritic knees were cultivated in suspension and in normal tension of oxygen. The cells were divided in 4 groups: control, stimulated with IL-1 or TNF-a, stimulated with meloxicam or parecoxib and the last one stimulated with meloxicam or parecoxib and IL-1 or TNF-a. Nuclear protein and RNA were extracted from these cells. cDNA was synthesized from RNA and real time PCR was performed with this product in order to determine HIF-1a expression. Nuclear protein was analyzed using the Western-Blotting method. Results: HIF-1a and HIF-1a mRNA was detectable in all cell groups, and there was not a statistic significant difference between them. Discussion: As half live of HIF-1a is extremely short when in normoxic and greater in hypoxic conditions, many researchers believe it is not possible to detect this protein in chondrocytes cultivated in normoxic environment. Our results presented expression of HIF-1a in normal oxygen tensions, probably due to the fact that chondrocytes were cultivated in suspension. As chondrocytes were obtained from advanced osteoarthritic knees and in such conditions the cells can be more resistant to the action of cytokines, this could explain why IL-1, TNF-a and antiinflamatory did not result in modification of HIF-1a
Mestrado
Clinica Medica
Mestre em Clinica Medica
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Lorenzo, Pilar. „Identification and characterization of a novel cartilage gene product CLIP, which is an early indicator of osteoarthritis“. Lund : Lund University, 1998. http://catalog.hathitrust.org/api/volumes/oclc/57426102.html.
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20
Stoker, Aaron. „Evaluation of the metabolic responses of normal and osteoarthritic cartilage in vitro and in vivo /“. Free to MU Campus, others may purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3144460.
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21
Coelho, Lívia de Paula. „Células-tronco mesenquimais autólogas no tratamento da osteoartrite induzida da articulação coxofemoral em coelhos (Oryctolagus cuniculus) /“. Jaboticabal, 2017. http://hdl.handle.net/11449/150483.
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Orientador: Bruno Watanabe MintoBanca: Luis Gustavo Gosuen Gonçalves Dias
Banca: Paulo César Jark
Resumo: A cartilagem articular possui capacidade de reparação limitada, aumentado a predisposição ao desenvolvimento de alterações degenerativas, muitas vezes irreversíveis. Diversas formas de tratamento, cirúrgicas ou conservativas, são descritas, entretanto a terapêutica da osteoartrite continua sendo grande desafio ao médico veterinário. Neste contexto, a pesquisa envolvendo células-tronco mesenquimais destaca-se na busca de melhorias e avanços na reparação da cartilagem articular. Objetivou-se, no presente projeto, comparar a regeneração cartilaginosa da articulação coxofemoral de coelhos, com e sem o transplante de células-tronco mesenquimais autólogas, por meio de exames radiográficos e histopatológicos. Dois grupos, com 15 animais da espécie leporina cada, foram submetidos à indução química de osteoartrite com solução de colagenase 2% na articulação coxofemoral direita. No Grupo 1 (Células-tronco) realizou-se a aplicação intra-articular de células-tronco mesenquimais autólogas, enquanto que, o Grupo 2 (Controle) foi constituído por animais submetidos à aplicação intra-articular de solução salina estéril. Foram realizadas avaliações radiográficas e histopatológicas aos 30, 60 e 90 dias após a aplicação. Os resultados histológicos deste ensaio indicam que células-tronco mesenquimais (Grupo 1) melhoraram discretamente a qualidade do tecido de reparo, de acordo com os critérios da escala semi-quantitativa ICRS 1 ("International Cartilage Repair Society"). O Grupo 1 (Células-Tronco... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The articular cartilage has limited repair capacity, leading to an increased risk for degenerative changes, potentially irreversible. Several treatments, surgical or not, are described, however osteoarthritis remains a major challenge for the veterinarian. In this context, research involving mesenchymal stem cells stands out. The aim of this study was to compare cartilage regeneration of the hip in rabbits, with and without the transplantation of autologous mesenchymal stem cells. Radiographic and histopathological evaluation were used. Thirty rabbits were submitted to chemical induction of osteoarthritis with a 2% colagenase in the right hip. They were divided into 2 groups of 15 animals each: Group 1 (intra-articular application of autologous mesenchymal stem cells) and Group 2 (control - intra-articular application of sterile saline solution). Radiographic and histopathological evaluations were performed at 30, 60 and 90 days after application. The mesenchymal stem cells group (Group 1) showed slight improvement of the quality of the repair tissue, according to the semi-quantitative scale criteria ICRS 1 (International Cartilage Repair Society). The Group 1 (Stem Cells) showed superiority in relation to Group 2, specially in the parameters joint surface, extracellular matrix and cellular distribution.
Mestre
22
Bishop, Joanna Charlotte. „Biology of the articular cartilage progenitor cells“. Thesis, Cardiff University, 2004. http://orca.cf.ac.uk/55374/.
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Campbell, E. M. „Measurement of articular joint cartilage by MRI“. Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597258.
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Magnetic Resonance Imaging (MRI) is increasingly used to assess damage and disease in articular joints. This Thesis describes improvements in hardware and pulse sequences, to facilitate the visualization and quantitation of articular cartilage in human and rabbit knees, and in interphalangeal (IP) finger joints. Work on the human knee focused on the acquisition of localised 3D data-sets from each compartment individually, using a surface coil in transmit/receive mode. The advantage of the increase spatial resolution from localised MRI, was illustrated by comparison of the resulting patella articular cartilage thickness measurements, with equivalent measurements based on 3D volume scans. Those results clearly demonstrated that low spatial resolution images can over-estimate articular cartilage thickness. Rabbit knees with induced 'Quinoline Arthropathy' (QA) and 'Rheumatoid Arthritis' (RA) were also imaged and by optimising the RF probe configuration, it was possible to improve the spatial resolution, as compared with literature reports. Articular cartilage visualisation of the normal and QA joints was optimum for MTC-subtraction images; edge detection maps of those joints clearly showed the articular cartilage boundaries for normal as well as the swollen articular cartilage. The late stage pathology of the RA joints when imaged prevented some contrast regimes from being fully assessed for articular cartilage visualisation. However, the high spatial resolution 3D acquisitions of these rabbit knees clearly demonstrated the full extent of the joint damage, and in particular the severity of bone erosions. Initially the finger work optimised the MRI acquisition and data processing protocols for simultaneously measuring the joint space thickness in 3 DIP and 3 PIP joints in one hand. The results illustrated both the sensitivity of the different statistical measurements and the potential for further evaluation. This work demonstrates the scope of MRI for quantitative analysis of articular cartilage. It also illustrates the benefits of optimising RF probes for the required region-of-interest (ROI) and pulse sequences for articular cartilage visualisation.
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Reissis, Nikolaos. „A novel method of articular cartilage repair“. Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1445027/.
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Articular cartilage repair of post-traumatic articular cartilage defects and well-defined articular cartilage pathology is challenging in clinical practice and has been the focus of investigations for many years. In the present thesis a newly developed polymer system, based on poly-ethyl-methacrylate PEMA polymer and tetra-hydro-furfuryl methacrylate THFMA monomer has been exploited for the repair of large, full-thickness articular cartilage defects, created in a weight-bearing surface in the rabbit knee joint. The method of implantation is simple and easily reproducible and can be performed in one stage with open arthrotomy or arthroscopy in clinical applications. Intravenous administration of the monomer did not elicit significant cardiorespiratory side effects. The repair tissue in defects treated with PEMA/THFMA was compared to control defects that healed 'naturally'. Macroscopic and histological/histochemical evaluation using the newly developed Articular Cartilage Repair Scoring System, immunohistochemistry, electron microscopy, image analysis as well as biochemical analysis were used for the characterisation of the repair tissue. The results demonstrated that the PEMA/THFMA polymer enhanced significantly the quality of repair up to 1 year postoperatively. The repair tissue contained numerous chondrocytes producing large amounts of proteoglycans and collagen type II, and it was completely bonded to the adjacent normal articular cartilage in the vast majority of the specimens. The enhancing effect of PEMA/THFMA in articular cartilage defects was also demonstrated in three age groups of rabbits at 6 weeks, thus increasing the potential clinical applications of the polymer. Furthermore, PEMA/THFMA was compared to the conventional bone cement PMMA/MMA. At 6 weeks post-implantation PEMA/THFMA produced significantly superior repair tissue, compared to PMMA/MMA, confirming the importance of the properties of the new polymer. Finally, PEMA/THFMA was exploited as a potential drug delivery system in vivo by loading human growth hormone in the polymer. It was shown that the loaded polymer repaired the defects with a proliferative type of tissue, resembling immature articular cartilage.
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Sasazaki, Yoshihiro. „Ultrastructure of articular cartilage under tensile strain“. Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410724.
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Inamdar, Sheetal Rajendra. „Nanoscale mechanics of collagen in articular cartilage“. Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/36223.
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Articular cartilage is a mechanically important soft tissue whose organisation at the micro- and nanoscale is critical for healthy joint function and where degeneration is associated with widespread disorders such as osteoarthritis. The tissue possesses a complex, graded and depth-dependent structure and at the nanoscale, cartilage mechanical functionality is dependent on the collagen and hydrated proteoglycans that form the extracellular matrix. The structure and in situ dynamic response of the collagen fibrils at the nanoscale, however, remain unclear. Here we utilise small angle X-ray diffraction to measure the depth-wise structure of the fibrillar architecture whilst performing time-resolved measurements during compression of bovine and human cartilage explants. We demonstrate the existence of a depth-dependent fibrillar pre-strain as determined by the D-periodicity, estimated at approximately 1-2%, due to osmotic swelling pressure from the proteoglycans. Furthermore, we reveal a rapid reduction and recovery of this pre-strain during stress relaxation, approximately 60 seconds after onset of peak load. Selective proteoglycan removal disrupts both collagen fibril pre-strain and transient responses during stress relaxation. Additionally, we show that IL-1β induced tissue inflammation also results in a reduction in fibrillar pre-strain and altered fibrillar mechanics. Cyclic loading induces a dynamic reduction and recovery in the D-period that is present regardless of loading rate or treatment, along with changes in diffraction peak intensities and widths. These findings suggest that the fibrils respond to loading via intra- and inter-fibrillar disordering alongside a transient response that is mediated by changes in hydration. These are the first studies to highlight previously unknown transient and cyclic responses to loading at the fibrillar level, and are likely to transform our understanding of the role of collagen fibril nano-mechanics in cartilage and other hydrated soft tissues. These methods can now be used to better understand cartilage in aging and other muscoskeletal diseases.
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Schroeder, Matthew O. „Biotribology : articular cartilage friction, wear, and lubrication /“. Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-12302008-063639/.
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Bont, Lambert G. M. de. „Temoromandibular joint articular cartilage structure and function“. Groningen : Rijksuniversiteit, 1985. http://catalog.hathitrust.org/api/volumes/oclc/38175470.html.
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Olsen, Sigb. „Modelling of articular cartilage load-carriage biomechanics“. Thesis, Queensland University of Technology, 2003.
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Jeffrey, Janet Elizabeth. „The response of articular cartilage to impact loading“. Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25206.
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Silva, Anderson Coutinho da. „Estudo da osteoartrose em joelhos de cães secundária à ruptura do ligamento cruzado cranial“. Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5145/tde-09062009-165130/.
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INTRODUÇÃO e OBJETIVO: A osteoartrite (OA) embora frequente tem patogênese incerta em humanos. Descrevemos modelo experimental original de OA em cães, analisando em dois tempos diferentes as consequências da Ruptura Espontânea do Ligamento Cruzado Cranial (RLCCr). MÉTODOS: Vinte animais machos com menos de 5 anos ( 20 a 45 Kg) com RLCCr submetidos à artrotomia para estabilização articular tiveram fragmentos articulares removidos para análise. O grupo RLCCr < 20 (10 animais) foi operado antes dos vinte dias e o grupo > 20 (10 animais) após 20 dias do início da lesão. Sete animais com OA pré-existente (OA) que morreram por quaisquer motivos e 7 animais normais (NC) provenientes do C.C.Z., serviram de grupos controles. Os animais foram avaliados clinica e radiologicamente. Foi colhido líquido sinovial dos animais operados e de outros 20 cães controles submetidos às cirurgias por diferentes causas. Para estudo morfológico, os fragmentos de cartilagens foram corados com H&E e Picrossirius. A gravidade do escore histológico da OA foi quantificada através da coloração com Safranina O. Analisou-se citocinas próinflamatórias (IL-6, TNF-alfa) e a quimiocina CCL2/MCP-1 nos líquidos sinoviais. RESULTADOS: Todos os cães tinham o teste de movimento da gaveta e exame de compressão da mesa tibial positivos. Achados radiográficos correlacionaram-se com maior tempo de RLCCr. Cartilagem articular de animais normais (NC) exibiram superfície preservada, disposição ordenada dos condrócitos e integridade da rede de colágeno. Exames histológicos em animais do grupo RLCCr < 20 mostraram irregularidades na superfície articular, diminuição no número de condrócitos e remodelamento de fibras de colágeno. No grupo > 20, observou-se osteófitos e irregularidades evidentes nas superfícies articulares. A gravidade do escore de acometimento histológico traduziu-se por intensa diminuição celular na superfície articular, com presença de clusters de condrócitos na região intermediária da cartilagem e total desorganização da rede de fibras de colágeno. A quimiocina CCL2/MCP-1 esteve aumentada no grupo com menos de 20 dias de lesão, enquanto a IL-6 foi mais expressiva nos animais operados tardiamente. CONCLUSÃO: O modelo experimental espontâneo de OA canino, estudado em dois tempos, é um instrumento original e útil para estudo da patogênese da osteoartrite, além de ter o mérito de preservar a integridade física dos animais de laboratórioINTRODUCTION and OBJECTIVE: Osteoarthritis (OA) is a frequent and severe rheumatic disease of unknown pathogenesis. We described an original experimental model of OA, analyzing the consequences of spontaneous cranial cruciate ligament rupture (RLCCr), occurred at two different times. METHOD: Twenty male animals, younger than 5 years old (20 to 45kg) with RLCCr were submitted to arthrotomy for articular stability and had cartilage fragments removed for analysis. The Group RLCCR < 20 (10 animals) was operated before 20 days and Group RLCCR > 20 (10 animals) after 20 days of beginning of lesion. Seven animals with pre-existent OA which died without any reason, and 7 normal animals (NC) from Service of Zoonosis Control were the control groups. The animals were submitted to clinical and radiological evaluations. Synovial fluid were collected from operated dogs and from another 20 control animals, submitted for surgical procedures for any reason. For the morphological study, the cartilage fragments were stained with H&E and Picrossirus. The score for OA severity was quantified using Safranin-O staining. Inflammatory cytokines (IL-6 and TNF alfa) and chemiokine CCL2/MCP-1 were measured in sinovial fluid. RESULTS: At physical examination, all the dogs had positive drawer and the tibial plateau compression tests. Knee Radiographic data showed that narrowing of joint space, osteophytes and erosions were more prominent in Group RLCCr> 20 animals. Articular cartilage of normal animals (NC) revealed preserved cartilage surface, organized disposition of chondrocytes and integrity of collagen net. Histological exams done in animals from Group RLLCr > 20 showed irregularities on articular surface, reduction of the number of chondrocytes and collagen fibers remodeling. Animals from Group RLCCR > 20 exhibited deep fibrillations, presence of chondrocytes clusters at intermediate area of cartilage, osteophytes and and total disorganization of the collagen fibers net. Chemiokine CCL2/MCP-1 was found overexpressed in dogs operated less than 20 days, while IL-6 was increased in late surgical group. CONCLUSION: The spontaneous model of canine RLCCr, studied at two distinct times, is an original and useful tool to understand pathogenesis of OA. Furthermore, the procedure preserves the animal integrity, becoming an Ethical laboratorial procedure
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Hoch, Johanna M. „SERUM CARTILAGE OLIGOMERIC MATRIX PROTEIN: A BIOMARKER FOR ACUTE ARTICULAR CARTILAGE DAMAGE“. UKnowledge, 2012. http://uknowledge.uky.edu/rehabsci_etds/3.
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Bone bruise lesions (BBL) are documented on MRIs diagnosing acute knee ligament injury (AKLI). Recent evidence has indicated that a majority of patients that sustain an AKLI, especially anterior cruciate ligament (ACL) knee injury, will develop post-traumatic osteoarthritis (PTOA) 10-20 years following injury. It has been proposed that the initial damage sustained to the articular cartilage overlying BBL causes a cascade of events that may result in PTOA.
Researchers have proposed a modification to treatment protocols for more severe BBL, or have stressed the need for the development of protective therapies to protect the articular cartilage. However, there are limited tools available to evaluate the clinical outcome of articular cartilage overlying BBL. Furthermore, damage to the cartilage overlying BBL may be different according to differing BBL severities. Therefore, the use of a cartilage degradation biomarker, serum cartilage oligomeric matrix protein (sCOMP) and the use of a BBL severity classification system may be useful to determine if differences exist between patients with and without BBL, and with differing BBL severities.
The purpose of this dissertation was to investigate the utility of sCOMP as a biomarker for acute articular cartilage damage. The purposes of these studies were to determine the inter and intraday reliability of this marker, to document sCOMP longitudinally in collegiate athletes and following AKLI, and to determine if differences in sCOMP and self-reported pain and function exist for patients with and without BBL, and differing BBL following AKLI.
The results of these studies indicated sCOMP measures had strong inter and intraday reliability. Additionally, exercise does seem to influence sCOMP levels; however, these elevations may not be clinically meaningful. Furthermore, sCOMP levels were not different between patients with BBL and without, and between differing BBL severities. The results of these studies support the use of a BBL severity classification for future research studies in order to further elucidate the outcomes of these lesions.
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Zhang, Le. „Neutral solute transport in cartilage“. Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 165 p, 2008. http://proquest.umi.com/pqdweb?did=1601524361&sid=8&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Lawrence, C. E. „The regeneration of articular tissues“. Thesis, Anglia Ruskin University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380722.
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Changes in the structural organization of cartilage and synovial tissue, or in the macromolecules produced by their cells, alter the properties of the tissues. Elucidation of the changes under controlled experimental conditions could make a significant contribution to the understanding of the pathogenesis of arthritis. To this end a model system has been developed to study proteoglycan and collagen regeneration in porcine articular cartilage and synovial tissue: partially depleted of matrix by exogenous enzyme(s), the tissues were maintained in organ culture, the medium consisting of Dulbecco's modification of Eagle's medium and 15% rabbit serum, and the responses of the chondrocytes and synoviocytes studied biochemically and histologically. Cleavage of proteoglycan core protein in cartilage explants by trypsin, equivalent to the disruption occurring in joint inflammation, induced glycosaminoglycan synthesis. The chondrocytes, particularly of the mid and hypertrophic zones, acquiring a basophilic territorial matrix and eventually an interterritorial matrix, which replaced the ex vivo material. Further damage to collagen by bacterial collagenase induced collagen synthesis, and enhanced glycosaminoglycan synthesis, but hyaluronic acid disruption proved partially inhibitory to recovery, the interterritorial matrix being less basophilic than comparable trypsinized explants. ³⁵SO₄ uptake by depleted explants showed a similar but sustained rate of glycosaminoglycan synthesis compared with untreated explants. The effects of corticosteroids, currently used for the temporary palliation of joint inflammation, on the regeneration processes were studied. The hydrolytic potential of the cultures and the frequency of medium changes had a profound effect on biologically active cortisol levels when cortisol succinate was present. Lower than physiological levels of cortisol (≤2.76 x 10^-7M) promoted glycosaminoglycan synthesis in all disrupted explants except those with cleaved hyaluronic acid chains. During the later stages of culture, in the presence of cortisol, (≤2.76 x 10-7M), the interterritorial glycosaminoglycan concentration increased. Whether collagen fibres were disrupted or not, collagen synthesis was evident, although with pharmacological concentrations of steroid (≤2.76 x 10^-6 M) all synthetic processes were increasingly inhibited. Exogenous trypsin induced extensive resorption of collagen fibres in minced synovial tissue, probably by activation of synovial collagenase. The destruction was partially reduced with trypsin inhibitor or cortisol. In areas of degradation macrophage-like cells accumulated but with early removal of trypsin, despite loss of collagen, fibroblast-like cells accumulated at the base of the explants with synthesized pericellular collagen evident. Collagen release into the medium was measured by an improved hydroxyproline assay designed to reduce interference from serum proteins. Although physiological doses of cortisol (≤2.76 x 10-7 M) enhanced collagen synthesis by, and the development of, the fibroblastic cells, extensive tissue repair was not observed, merely the formation of a cell population in the Millipore membrane. This model of tissue regeneration, remodelling and repair leads to the conclusion that within the arthritic joint the chondrocyte has the potential to rapidly attempt to repair damaged matrix, the extent of synthesis being proportional to the extent and type of matrix disruption. The chondrocyte responds by synthesizing glycosaminoglycans, that aggregate within the matrix, and collagen, with cortisol, at below physiological concentrations, enhancing this regeneration. Synovial tissue did not recover from disruption although the synoviocytes, on reversion to fibroblast-like cells, accumulated new collagen.
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Brodkin, Kathryn Rhea. „Chondrocyte behavior in monolayer culture : the effects of protein substrates and culture media“. Thesis, Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/20216.
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Fuente, Fabien Raymond. „Electromechanical indentation properties of hydrated biomaterials“. Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17142.
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Farias, Neto Arcelino 1983. „Influência de alterações oclusais na articulação temporomandibular e crescimento mandibular = estudo em modelo animal“. [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290520.
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Orientador: Célia Marisa Rizzatti BarbosaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: A cartilagem articular do côndilo mandibular é responsável pelo crescimento ósseo endocondral durante o desenvolvimento mandibular. Ela depende do funcionamento adequado da articulação temporomandibular (ATM) para sua diferenciação e maturação. Trabalhos demonstram que a manipulação funcional da mandíbula foi capaz de alterar a dinâmica fisiológica dessa cartilagem. Nesse sentido, a protrusão diminuiria a ação de cargas sobre o côndilo mandibular, estimulando o crescimento endocondral, e de forma inversa, a retrusão aumentaria a pressão sobre a cartilagem, inibindo o crescimento. Essas técnicas têm sido utilizadas com relativo sucesso na ortopedia facial com o intuito de corrigir discrepâncias maxilo-mandibulares. Entretanto, alguns quadros patológicos presentes nas ATMs podem alterar o seu desenvolvimento normal. Um dos fatores etiológicos que pode ser associado à presença de alterações no côndilo mandibular é a oclusão dental. A hipótese formulada é de que a presença de instabilidade ortopédica causada por um fator oclusal durante a fase de desenvolvimento pode levar à deficiência do crescimento mandibular e alterações intra-articulares. Assim, este trabalho teve por objetivo avaliar, em modelo animal, alterações da oclusão dental sobre o crescimento mandibular e tecidos intra-articulares. O estudo foi randomizado e cego. Foram utilizadas 40 ratas Wistar com 5 semanas de idade divididas aleatoriamente em 4 grupos com o mesmo número de animais: controle, com interferência oclusal, com ausência dos molares inferiores unilateral e com ausência dos molares inferiores bilateral. Os animais foram acompanhados por 8 semanas, período que correspondeu a sua fase de maturação óssea. Após esse período, os animais foram sacrificados e realizou-se tomografia computadorizada de feixe cônico (Cone beam) de suas cabeças para construção de protótipos de biomodelos, sobre os quais foram mensurados o comprimento da mandíbula, a altura do ramo mandibular e distância intercondilar. Em seguida, as articulações temporomandibulares foram cuidadosamente preparadas para análise imunohistoquímica dos níveis de colágeno tipo II, Fator de Crescimento Endotelial Vascular, e Interleucina 1? na cartilagem condilar. Os dados foram submetidos a análise estatística através do Software SPSS versão 17.0. As médias entre os grupos foram comparadas através do One-way Anova, enquanto as diferenças entre os lados da mandíbula foram avaliadas através do teste t de Student (?=0.05). A partir da análise dos resultados, observou-se que alterações oclusais podem afetar o desenvolvimento do osso mandibular, bem como alterar a expressão de Colágeno tipo II, Fator de Crescimento Endotelial Vascular e Interleucina 1? na cartilagem condilar. Diante do exposto, conclui-se que a oclusão dentária é capaz de interferir na dinâmica dos tecidos intra-articulares, sendo um fator importante durante o desenvolvimento craniofacial
Abstract: The condylar cartilage regulates the endochondral ossification during mandibular development. Mechanical stimulus in the temporomandibular joint (TMJ) plays an important role in cell proliferation and differentiation of mandibular condyle. Studies have shown that functional mandibular displacement can affect TMJ cartilage dynamics. Mandibular advancement induces profound metabolic changes in the condyle and enhances growth. In contrast, mandibular retraction reduces growth. The overall picture emerging from the data is that unloading of the condyle increases growth, while loading reduces it. Therefore, dental occlusion could be one of the factors associated with the alteration of the TMJ growth. The hypothesis is that orthopedic instability caused by occlusal factors present during TMJ development can affect mandibular growth and intra-articular tissue. Thus, the purpose of this study was to evaluate the influence of dental occlusion on mandibular growth and intra-articular tissue in Wistar rats. The study was randomized and blinded. Forty 5 weeks old female Wistar rats composed the sample. The animals were randomly allocated to four groups with the same number of rats: (1) control, (2) occlusal appliance for functional posterior displacement of the mandible, (3) unilateral mandibular tooth extraction, (4) bilateral mandibular tooth extraction. The rats were sacrificed after 8 weeks, when they had achieved skeletal maturity. Immediately after death, the heads were fixed in 10% paraformaldehyde, and cone beam CT scan images were taken using the Classic I-CAT (Imaging Sciences International, Hatfield, PA, USA). The 3-dimensional images of rats' skulls were exported in multifile Digital Imaging and Communications in Medicine (DICOM) format, and acrylic rapid-prototyped templates of the mandibles were constructed for measurement of mandibular growth. Immunostaining was used for the detection of type II collagen, vascular endothelial growth factor (VEGF) and interleukin-1?. The data were processed with SPSS software (V 17.0 for Windows, SPSS Inc, Chicago, IL, USA). Differences among the groups were analyzed by one-way ANOVA (Tukey test as post-hoc test), while differences between sides were analyzed by non-paired Student's t test. Shapiro-Wilk and Levene tests were used to observe normality and variance homogeneity, respectively. Confidence level was set at 5%. The results of this study showed that dental occlusion is an important factor for the integrity of intra-articular tissues and to the healthy craniofacial development, emphasizing the importance of early treatment to normalize occlusion and create appropriate conditions for normal craniofacial development
Doutorado
Protese Dental
Doutor em Clínica Odontológica
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Lei, Fulin. „Modeling of articular cartilage optimization, large deformation, and microstructure /“. Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 1.21 Mb., 176 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:3220728.
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Nugent, Gayle E. „Biomechanical regulation of articular cartilage metabolism of proteoglycan 4 and articular surface integrity“. Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3310007.
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Thesis (Ph. D.)--University of California, San Diego, 2006.Title from first page of PDF file (viewed September 19, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
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Smyth, Patrick A. „Viscoelastic behavior of articular cartilage in unconfined compression“. Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47656.
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Previous decades of cartilage research have predominantly focused on decoupling the solid and fluid interactions of the mechanical response. The resulting biphasic and triphasic models are widely used in the biomechanics community. However, a simple viscoelastic model is able to account for the stress-relaxation behavior of cartilage, without the added complexity of solid and fluid interactions. Using a viscoelastic model, cartilage is considered a single material with elastic and dissipative properties. A mechanical characterization is made with fewer material parameters than are required by the conventional biphasic and triphasic models. This approach has tremendous utility when comparing cartilage of different species and varying healths. Additionally, the viscoelastic models can be easily extended in dynamic analysis and FEA programs.
Cartilage primarily experiences compressive motion during exercise. Therefore, to mimic biological function, a mechanical test should also compress the cartilage. One such test is a viscoelastic stress-relaxation experiment. The Prony and fractional calculus viscoelastic models have shown promise in modeling stress-relaxation of equine articular cartilage. The elastic-viscoelastic correspondence principle is used to extend linear viscoelasticity to the frequency domain. This provides a comparison of articular cartilage based on stored and dissipated moduli. The storage and loss moduli metrics are hypothesized to serve as benchmarks for evaluating osteoarthritic cartilage, and provide guidelines for newly engineered bio-materials.
The main goal of the current study is to test the applicability of modeling articular cartilage with viscoelastic models. A secondary goal is to establish a rigorous set of harvesting techniques that allows access to fresh explants with minimal environmental exposure. With a complex substance like cartilage, it is crucial to avoid unnecessary emph{in vitro} environmental exposure. Additional areas of study include: determining the strain-dependency of the mechanical response, exploring the response of cartilage in different fluid mediums such as saline, synovial fluid, and synthetic substitutes, and studying the time-dependent properties of cartilage during stress-relaxation experiments. Equine stifle joints, which are mechanically analogous to human knees, are harvested and used for analysis in this study. It is believed that the proposed viscoelastic models can model other articulating joints as well. If viscoelastic theory can be used to characterize cartilage, then comparisons can be drawn between real and artificial cartilage, leading to better joint replacement technology.
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Solomon, Daniel. „Phosphate transport and mineralising processes in articular cartilage“. Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436955.
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Thomas, Carla Marie. „Chondrocyte death by apoptosis and articular cartilage degradation“. Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445808.
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Clements, Kristen Mary. „Mechanical disruption of articular cartilage cells and matrix“. Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340082.
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Marcus, Paula Louise. „Plasticity and interactions of articular cartilage progenitor cells“. Thesis, Cardiff University, 2008. http://orca.cf.ac.uk/54742/.
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Articular cartilage is an avascular and aneural tissue and this is, in part, attributable to its low intrinsic capacity for repair after injury. Research is now focusing on alternate cell sources for tissue engineering of damaged cartilage, and recently a population of progenitor cells has been identified within the surface zone of bovine articular cartilage. These cells are capable of differentiating along a variety of mesenchymal lineages and are thought to be required for the appositional growth of the cartilage. The aims of this thesis were to further characterise these cells and determine factors affecting their differentiation. Prolonged growth of the clonal cells in culture was found to alter the ability of the cells to differentiate into a hyaline-like tissue, although these changes didn't always result in a decrease in the chondrogenic capacity. The rate of cell growth was also found to slightly affect the ability of the cells to differentiate, with more rapidly growing cells producing a matrix high in glycosaminoglycans. After short term culture, the cells also altered their expression of three different glycosaminoglycans sulphate epitopes 3B3(-), 4C3 and 7D4. When injected intramuscularly, the chondroprogenitor cells failed to form cartilage pellets despite expressing cartilage related genes. The progenitor cells also appeared unable to functionally engraft into the surrounding tissue, although one clonal cell line expressed the endothelial marker PECAM-1. Within this study we also assessed the ability of the chondroprogenitor cells to express connexins, and form functional gap junctions. The cells were found to fluctuate their connexin expression, although they maintained Cx43 expression throughout culture. Using a novel ultrasound standing wave trap, it was found that the cells failed to upregulate connexin after cell contact resulting in non-functional junctions, whilst the cells were able to form functional gap junctions with terminally differentiated chondrocytes. Treating the clonal cells with growth factors to enhance chondrogenesis also failed to cause the cells to functionally communicate. Finally we looked at the cellular organisation of the tissue to determine if paired cells within the surface zone of the cartilage may contain a progenitor population. These paired cells labelled positively for Notch-1, which is known to affect the clonality of the progenitor cells and could possibly signify the presence of the progenitor cell population. Cellular interactions are vital for controlling and coordinating cell differentiation, and manipulating cellular interactions could be an excellent way to enhance the chondrogenic differentiation of the cells and possibly improve tissue integration.
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Warren, James Phillip. „Self-assembling peptide hydrogels for articular cartilage repair“. Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/17538/.
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Osteoarthritis affects millions of people globally, with damage to articular cartilage causing pain and altered mechanics during articulation. The treatment for late stage osteoarthritis is surgical intervention ultimately leading to total joint replacements. These treatments are not ideal for younger or more active patients so there is a clinical need for an early stage intervention treatment to reduce or stop the progression of osteoarthritis. It has been reported that there is a correlation between the loss of glycosaminoglycans (GAGs) from within osteoarthritic cartilage and the changes in biomechanics of the cartilage. It is hypothesized that the re-introduction of GAGs into early stage osteoarthritic cartilage through the use of permanent linkage and integration into a self-assembling peptide hydrogel matrix which could penetrate the cartilage tissue would potentially restore the resistance to deformation observed in osteoarthritic cartilage. Initially, synthetic self-assembling peptide-chondroitin sulfate (CS) conjugates were synthesized through utilizing copper-catalyzed click chemistry and subsequently characterized. The chosen peptide-CS conjugates were then incorporated into self-assembling peptide hydrogels and the morphologies and gel properties were investigated and evaluated in terms of the closest resemblance to the natural properties of the surrounding cartilage into which the hydrogels would be eventually injected. The best hydrogel candidates were then taken forward to be injected into a GAG depleted early stage osteoarthritic porcine cartilage model developed by Andres Barco (University of Leeds) where a severely GAG depleted state had been produced through a succession of surfactant and phosphate buffered saline washes. The hydrogels were doped with fluorescently labelled material which integrated into the hydrogel matrix, then injected into the cartilage tissue in a monomeric state. The hydrogels then self-assembled in situ and the deformation of the tissue was measured through creep indentation. The introduction of the peptide-CS conjugate showed significant restoration of resistance to deformation.
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Wei, Wenbo. „Knee Osteoarthritis: gagCEST MR Imaging of Articular Cartilage“. The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1365247669.
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Rebenda, David. „Effect of Viscosupplementation on Friction of Articular Cartilage“. Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-449087.
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Disertační práce se zabývá experimentálním studiem viskosuplementů na bázi kyseliny hyaluronové, které se aplikují do synoviálních kloubů postižených osteoartrózou. Hlavní pozornost byla věnována objasnění vlivu koncentrace a molekulové hmotnosti kyseliny hyaluronové na tření v kontaktu kloubí chrupavky resp. změnám tření v kontaktu po smíchání osteoartritické synoviální kapaliny s exogenní kyselinou hyaluronovou. Důležitou součástí experimentů bylo rovněž studium reologických vlastností synoviální kapaliny a kyseliny hyaluronové. Výsledky ukázaly, že molekulová hmotnost kyseliny hyaluronové významně ovlivňuje viskozitu a viskoelastické vlastnosti roztoku. Výrazná závislost mezi reologickými vlastnostmi kyseliny hyaluronové a třením v kontaktu však nebyla pozorována. Přimíchání kyseliny hyaluronové do synoviální kapaliny způsobí výrazný pokles součinitele tření v kontaktu. Rozdíly mezi viskosuplementy obsahující kyselinu hyaluronovou s různou molekulovou hmotností ale nijak výrazné nejsou. Nicméně, výsledky poukazují na možné ovlivnění režimu mazání v důsledku vysoké molekulové hmotnosti kyseliny hyaluronové. Tyto původní výsledky rozšiřují pochopení mechanizmů, ke kterým dochází v kloubu bezprostředně do vstříknutí kyseliny hyaluronové a mohou být použity při dalším vývoji viskosuplementů či v klinické praxi.
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Docimo, Jennifer E. „Diffusion measurements in articular cartilage under compressive loading“. Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 102 p, 2008. http://proquest.umi.com/pqdweb?did=1654494261&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Arora, Arvind. „Potential of qMRI in the study of articular cartilage and cartilage repair tissue“. Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613644.
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Whittaker, Katharina Anna. „Ion transport by isolated bovine articular chondroyctes“. Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316916.
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