• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • Tagged with
  • 4
  • 4
  • 4
  • 4
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The Effect of Anterior Knee Pain on Serum Cartilage Oligomeric Matrix Protein and Muscular Cocontraction During Running

Woodland, Scott T. 14 June 2013 (has links) (PDF)
Knee pain can alter lower-extremity neuromechanics and often results in functional disability. The relationship between lower-extremity neuromechanical alterations, due to anterior knee pain, and articular cartilage condition is unclear. The purpose of this study was to determine the independent effect of anterior knee pain during running on articular cartilage condition, as reflected by serum cartilage oligomeric matrix protein concentrations and muscle cocontraction duration. Seven men and five women completed a 30-min run in three different sessions: control (no infusion), sham (isotonic saline infusion), and pain (hypertonic saline infusion). Saline was infused into the right infrapatellar fat pad for the duration of the run. Subject-perceived pain was recorded every 3 min on a 100-mm visual analog scale. During the run, bilateral electromyography was recorded for five leg muscles, and heel and toe markers were used to track foot position. During the 30-min run of the pain session average subject-perceived pain was 27.8 (SD = 2.3 mm) and 19.7 (SD = 1.9) mm greater than during the control (0.0 mm) and sham (8.1 mm) session, respectively (p < 0.01). Knee pain while running did not result in changes in muscular cocontraction duration (p = 0.13). Blood samples were drawn prior to the run, immediately following the run, and 60 min following the run. Samples were analyzed using enzyme-linked immunosortbent assay to determine serum cartilage oligomeric matrix protein concentration. Average serum cartilage oligomeric matrix protein concentration was 14% greater at immediate post run (132.19 ± 158.61 ng/ml; Range = 22.61-290.81 ng/ml) relative to pre run (116.02 ± 118.87 ng/ml; Range = 19.81-234.89 ng/ml) (p < 0.01), and 18% less at 60 min post run (108.45 ± 171.78 ng/ml; Range = 20.84-280.23 ng/ml) relative to immediate post run (Figure 4; p < 0.01). Serum cartilage oligomeric matrix protein did not significantly differ between baseline and 60 min post-exercise (p = 0.29). There was not a difference in cartilage oligomeric matrix protein concentration between sessions. Knee pain while running does not cause an increase in serum cartilage oligomeric matrix protein concentration (p = 0.29). There are two important findings from this study. First, anterior knee pain during a 30 min running session does not appear to independently affect cartilage oligomeric matrix protein concentrations. This implies other factors, aside from anterior knee pain alone, influence articular cartilage degradation during movement that occurs while individuals are experiencing anterior knee pain. Second, the present experimental anterior knee pain model can be used to evaluate the independent effects of anterior knee pain over an extended duration while subjects perform a dynamic activity like running.
2

Genetics and Biomarkers of Osteoarthritis and Joint Hypermobility

Chen, Hsiang-Cheng January 2009 (has links)
<p>Osteoarthritis (OA) is the most common joint disorder causing chronic disability in the world population. By the year 2030, an estimated one fifth of this population will be affected by OA. Although OA is regarded as a multi-factorial disorder with both environmental and genetic components, the exact pathogenesis remains unknown. </p><p> In this study, we hypothesize that biomarkers associated with OA can be used as quantitative traits of OA, and provide enough power to identify new genes or replicate known gene associations for OA. We established an extensive family called the CARRIAGE (CARolinas Region Interaction of Aging, Genes and Environment) family. Then, we measured and analyzed seven OA-related biomarkers (HA, COMP, PIIANP, CPII, C2C, hs-CRP and GSP) in this extensive family to evaluate their association with OA clinical phenotypes. These findings suggest that OA biomarkers can reflect hand OA in this large multigenerational family. Therefore, we performed nonparametric variance components analysis to evaluate heritability for quantitative traits for those biomarkers. Finally, based upon OA biomarkers with high heritability, we performed a genome-wide linkage scan. Our results provide the first evidence of genetic susceptibility loci identified by OA-related biomarkers, indicating several genetic loci potentially contributing to the genetic diversity of OA. </p><p> Meanwhile, we identified joint hypermobility as a factor which reduces OA risk and has an inverse association with serum COMP levels in this family. The relationship between lower serum COMP and OA have been further validated in another Caucasian GOGO (Genetics of Generalized Osteoarthritis) population. Therefore, we further hypothesize that joint hypermobility, having the characteristic of a decreased OA risk, can serve as a quantitative trait for identifying protective loci for OA. Then, we performed nonparametric variance components analysis to evaluate the heritability of joint hypermobility. The result also shows joint hypermobility has substantial heritable components in this family. Lastly, based on the same genome-wide linkage scan, we identify genetic susceptibility loci for joint hypermobility. </p><p> In conclusion, our work provides the first linkage study to identify genetic loci associated with OA using biological markers. Furthermore, we have also shown genetic susceptibility loci for joint hypermobility, possibly implying protective loci for OA.</p> / Dissertation
3

Estudo do comportamento biomecânico e da expressão galectina-3 e comp, biomarcadores do turnover de tecidos articulares da sínfise púbica de camundongos durante a prenhez e pos-parto / Study of biomechanical behavior and expressiom galectin-3 and comp, biomarkers turnover of tissue joint of pubic symphysis of mice during pregnancy and postpartum

Silva, Monica Maria Moreira, 1960- 27 August 2018 (has links)
Orientadores: Paulo Pinto Joazeiro, Luiz Carlos Alves / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-27T05:21:21Z (GMT). No. of bitstreams: 1 Silva_MonicaMariaMoreira_D.pdf: 3522039 bytes, checksum: c8adbfe076ccc79eaa19efeb2f0d8fe7 (MD5) Previous issue date: 2014 / Resumo: Em camundongos, a sínfise púbica (SP) é metabolicamente ativa durante a prenhez. As adaptações orquestradas por hormônios e a sobrecarga mecânica imposta na sínfise, que gradualmente dá lugar ao ligamento interpúbico (Lip) e ao seu "relaxamento" no final da prenhez permitem a passagem da prole pelo canal do parto. Tais modificações oferecem oportunidade para estudo de remodelação de tecidos semelhantes às que ocorrem nas disfunções e distopias do assoalho pélvico feminino. Estudaram-se características morfológicas, imunohistoquímica das proteínas Galectina-3(GAL3) e CartilageOligomericProtein Matrix (COMP) e o comportamento biomecânico, na SP de camundongos fêmeas adultas jovens, durante a primeira prenhez e após o parto por meio de técnicas histológicas convencionais, imunohistoquímica, microscopia de luz, eletrônica de transmissão e varredura. Nas análises da organização fibrilar utilizou-se transformada rápida de Fourier (FFT) e do comportamento biomecânico ensaio destrutivo de tração uniaxial em máquina de testes universal com velocidade constante e força progressiva nas SP/Lip de camundongos C57BL6 grupos: (NP-controle), 12, 15 e 19 dias (d) após a verificação do plug vaginal e no 30, 50 e 100dias após o parto (dpp). No ensaio de tração uniaxial, a força máxima necessária para o início da ruptura do tecido diminuiu no decorrer da prenhez, sendo o menor valor medido no dia do parto, aumentou a partir deste dia, e no 10dpp retornou a valores próximos aosdos animais NP. A energia total de ruptura (ETR) diminuiu no 12d e a partir de 15d aumentou até o 5dpp, no 10dpp, diminuiu porém se manteve menor que o NP. Na Imunolocalização das proteínas COMP e GAL3 foram detectadas em todos os grupos, com variações no tipo celular e na localização. A morfologia bicorne do útero de camundongos e o peso do útero com os filhotes alteram os estímulos mecânicos nos tecidos interpúbicos e contribuem para sua remodelação. No 3dpp, quando os estímulos mecânicos foram abruptamente retirados no parto, observaram-se organelas compostas por microtúbulos semelhante a cílio solitário não móvel, citado como organela mecanosensorial. O comportamento biomecânico dos tecidos interpúbicos durante a prenhez e após o parto foi coerente com a histoarquitetura destes e a imunolocalização das proteínas COMP e GAL-3, à medida que o comportamento biomecânico dos tecidos se modifica são indicativos que essas proteínas estão envolvidas no remodelamento de transições de elementos ósseos e ligamentares e fibrocatilaginosas durante a prenhez e após o parto. Este remodelamento que proporciona afastamento de ossos púbicos e a rápida recuperação que se inicia pós-parto, oferece suporte ao canal de parto de animais que possuem útero bicorne a exemplo do camundongo, morcego e cobaia / Abstract: In mice, the pubic symphysis (PS) is metabolically active during pregnancy. Adaptations orchestrated by hormones and mechanical overload that the symphysis goes through during this period, which gradually gives place to an interpubic ligament (IpL) and the relaxation at the end of pregnancy, allows the passage of offspring through the birth canal. Such changes provide an opportunity to study remodeling of tissues such as those that occur in disorders and dystopias of the female pelvic floor. We studied morphological, immunohistochemical analysis of galectin-3 (GAL3) and Cartilage Oligomeric Matrix Protein (COMP) proteins and the biomechanical behavior in young adult females PS mice during first pregnancy and postpartum (dpp) through conventional histological techniques, immunohistochemistry and light,transmition and scanning electron microscopies. In analyzes of fibrillar organization we used fast Fourier transform and the biomechanical behavior destructive tensile testing in a universal testing machine with constant speed and progressive force in the PS/IpL C57BL6 mice groups: (NP-control), 12, 15 and 19 days (d) after checking the vaginal plug and 3th, 5th and 10thpp. In tensile testing the maximum force required to initiate the rupture of the tissue decreased in the course of pregnancy, with the lowest value measured at day of birth, increasing from this day on and at the 10dpp returned to the NP individual¿s value.The total rupture energy (TRE) decreasesat d12 and increased from d15 until 5dpp, decreasing at the 10dpp but remained lower than the NP. Immunolocalization of COMP and GAL3 proteins were detected in all groups, with variations in cell type and location. The bicornuate uterus morphology of the mice and the weight of the uterus with cubs alter the mechanical stimuli in interpubic tissues, contribute to its remodeling. In 3dpp when mechanical stimuli were abruptly removed at birth. It was observed organelles consisting of microtubules that were similar to a solitary cilium quoted as mechanosensory organelle.The biomechanical behavior of interpubic tissues during pregnancy and after delivery was consistent with the histoarchitecture and immunolocalization of COMP and GAL-3 protein, as the biomechanical behavior of the tissue changes are indicative that these proteins are involved in the remodeling of transitions bony and ligamentous elements and fibrocartilaginous during pregnancy and after childbirth. This remodeling that provides removal of pubic bones and a quick postpartum recovery, offers birth canal support of animals that have bicornuate uterus such as the mouse, guinea pig and bat / Doutorado / Biologia Tecidual / Doutora em Biologia Celular e Estrutural
4

Biolubricants and Biolubrication

Wang, Min January 2014 (has links)
The main objective of this thesis work was to gain understanding of the principles of biolubrication, focusing on synergistic effects between biolubricants. To this end surface force and friction measurements were carried out by means of Atomic Force Microscopy, using hydrophilic and hydrophobic model surfaces in salt solutions of high ionic strength (≈ 150 mM) in presence of different biolubricants. There was also a need to gain information on the adsorbed layers formed by the biolubricants. This was achieved by using a range of methods such as Atomic Force Microscopy PeakForce imaging, Quartz Crystal Microbalance with Dissipation, Dynamic Light Scattering and X-Ray Reflectometry. By combining data from these techniques, detailed information about the adsorbed layers could be obtained.The biolubricants that were chosen for investigation were a phospholipid, hyaluronan, lubricin, and cartilage oligomeric matrix protein (COMP) that all exist in the synovial joint area. First the lubrication ability of these components alone was investigated, and then focus was turned to two pairs that are known or assumed to associate in the synovial area. Of the biolubricants that were investigated, it was only the phospholipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) that was found to be an efficient lubricant on its own. Deposited DPPC bilayers on silica surfaces were found to be able to provide very low friction coefficients (≈ 0.01) up to high pressures, ≈ 50 MPa. A higher load bearing capacity was found for DPPC in the liquid crystalline state compared to in the gel state.The first synergy pair that was explored was DPPC and hyaluronan, that is known to associate on the cartilage surface, and we also noticed association between hyaluronan and DPPC vesicles as well as with adsorbed DPPC bilayers. By combining these two components a lubrication performance similar to that of DPPC alone could be achieved, even though the friction coefficient in presence of hyaluronan was found to be slightly higher. The synergy here is thus not in form of an increased performance, but rather that the presence of hyaluronan allows a large amount of the phospholipid lubricant to accumulate where it is needed, i.e. on the sliding surfaces.The other synergy pair was lubricin and COMP that recently has been shown to be co-localized on the cartilage surface, and thus suggested to associate with each other. Lubricin, as a single component, provided poor lubrication of PMMA surfaces, which we utilized as model hydrophobic surfaces. However, if COMP first was allowed to coat the surface, and then lubricin was added a low friction coefficient (≈ 0.03) was found. In this case the synergy arises from COMP facilitating strong anchoring of lubricin to the surface in conformations that provide good lubrication performance. / Huvudsyftet med det här avhandlingsarbetet var att öka förståelsen för den låga friktion som finns i vissa biologiska system, med fokus på synergistiska effekter mellan de smörjande molekylerna. För detta ändamål studerades ytkrafter och friktion med hjälp av atomkraftsmikroskopi. Mätningarna utfördes med hydrofila och hydrofoba modellytor i lösningar med hög salthalt (≈ 150 mM) i närvaro av smörjande biomolekyler. Det var också nödvändigt att få information om de adsorberade skikten av biomolekyler. Det åstadkoms med hjälp av en rad tekniker så som AFM PeakForce avbildning, kvartskristallmikrovåg, dynamisk ljusspridning och röntgen reflektometri. Genom att kombinera data från dessa tekniker erhölls detaljerad information om de smörjande skikten.De smörjande biomolekyler som valdes ut för studierna var en fosfolipid, hyaluronan, lubricin, and cartilage oligomeric matrix protein (COMP) vilka alla finns i synovialledsområdet. Först undersöktes den smörjande förmågan hos dessa komponenter var för sig, och sedan fokuserade vi på två par av biomolekyler som man vet eller antar bildar associationsstrukturer i synovialleder. Av de enskilda biomolekyler som undersöktes var det endast fosfolipiden 1,2-dipalmitoyl-sn-glycero-3-fosfokoline (DPPC) som visade sig vara en effektivt smörjande molekyl. Deponerade biskikt av DPPC på silikaytor gav upphov till mycket låga friktionskoefficienter (≈ 0.01) upp till höga pålagda tryck, ≈ 50 MPa. DPPC bilager i flytande kristallin fas visade sig ha högre lastbärande förmåga än DPPC bilager i geltillstånd.Det första synergistiska par som undersöktes var DPPC och hyaluronan vilka man vet associerar på broskytan, och vi visade att hyaluronan associerar med såväl DPPC vesiklar som med DPPC bilager. Genom att kombinera dessa två komponenter uppmättes en smörjande förmåga som var jämförbar med den som DPPC ensam uppvisar. Även om friktionskoefficienten var något högre i närvaro av hyaluronan. Synergieffekten här består inte av en bättre smörjande förmåga, utan istället gör närvaron av hyaluronan att de smörjande fosfolipiderna kan ansamlas i stora mängder där de behövs, dvs. på de glidande ytorna.Det andra synergiparet var lubricin och COMP vilka nyligen har visats vara lokaliserade på samma platser på broskytan, vilket tyder på att de associerar med varandra. På egen hand var lubricins smörjande förmåga av PMMA, våra hydrofoba modellytor, dålig. Emellertid, om COMP först adsorberades på PMMA och sedan lubricin tillsattes uppmättes en låg friktionskoefficient (≈ 0.03). I det här fallet består synergin av att COMP möjliggör en stark inbindning till ytan av lubricin i konformationer som ger god smörjande förmåga. / <p>QC 20141202</p> / Stiftelsen för strategisk forskning - SSF

Page generated in 0.1209 seconds