@phdthesis{Berberich2024,
  author    = {Berberich, Oliver},
  title     = {Lateral Cartilage Tissue Integration - Evaluation of Bonding Strength and Tissue Integration \(in\) \(vitro\) Utilizing Biomaterials and Adhesives},
  doi       = {10.25972/OPUS-34602},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-346028},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2024},
  abstract  = {Articular cartilage defects represent one of the most challenging clinical problem for orthopedic surgeons and cartilage damage after trauma can result in debilitating joint pain, functional impairment and in the long-term development of osteoarthritis. The lateral cartilage-cartilage integration is crucial for the long-term success and to prevent further tissue degeneration. Tissue adhesives and sealants are becoming increasingly more popular and can be a beneficial approach in fostering tissue integration, particularly in tissues like cartilage where alternative techniques, such as suturing, would instead introduce further damage. However, adhesive materials still require optimization regarding the maximization of adhesion strength on the one hand and long-term tissue integration on the other hand. In vitro models can be a valuable support in the investigation of potential candidates and their functional mechanisms. For the conducted experiments within this work, an in vitro disc/ring model obtained from porcine articular cartilage tissue was established. In addition to qualitative evaluation of regeneration, this model facilitates the implementation of biomechanical tests to quantify cartilage integration strength. Construct harvesting for histology and other evaluation methods could be standardized and is ethically less questionable compared to in vivo testing. The opportunity of cell culture technique application for the in vitro model allowed a better understanding of cartilage integration processes. Tissue bonding requires chemical or physical interaction of the adhesive material and the substrate. Adhesive hydrogels can bind to the defect interface and simultaneously fill the gap of irregularly shaped defect voids. Fibrin gels are derived from the physiological blood-clot formation and are clinically applied for wound closure. Within this work, comparisons of different fibrin glue formulations with the commercial BioGlue® were assessed, which highlighted the need for good biocompatibility when applied on cartilage tissue in order to achieve satisfying long-term integration. Fibrin gel formulations can be adapted with regard to their long-term stability and when applied on cartilage disc/ring constructs improved integrative repair is observable. The kinetic of repairing processes was investigated in fibrin-treated cartilage composites as part of this work. After three days in vitro cultivation, deposited extracellular matrix (ECM) was obvious at the glued interface that increased further over time. Interfacial cell invasion from the surrounding native cartilage was detected from day ten of tissue culture. The ECM formation relies on molecular factors, e.g., as was shown representatively for ascorbic acid, and contributes to increasing integration strengths over time. The experiments performed with fibrin revealed that the treatment with a biocompatible adhesive that allows cartilage neosynthesis favors lateral cartilage integration in the long term. However, fibrin has limited immediate bonding strength, which is disadvantageous for use on articular cartilage that is subject to high mechanical stress. The continuing aim of this thesis was to further develop adhesive mechanisms and new adhesive hydrogels that retain the positive properties of fibrin but have an increased immediate bonding strength. Two different photochemical approaches with the advantage of on-demand bonding were tested. Such treatment potentially eases the application for the professional user. First, an UV light induced crosslinking mechanism was transferred to fibrin glue to provide additional bonding strength. For this, the cartilage surface was functionalized with highly reactive light-sensitive diazirine groups, which allowed additional covalent bonds to the fibrin matrix and thus increased the adhesive strength. However, the disadvantages of this approach were the multi-step bonding reactions, the need for enzymatic pretreatment of the cartilage, expensive reagents, potential UV-light damage, and potential toxicity hazards. Due to the mentioned disadvantages, no further experiments, including long-term culture, were carried out. A second photosensitive approach focused on blue light induced crosslinking of fibrinogen (RuFib) via a photoinitiator molecule instead of using thrombin as a crosslinking mediator like in normal fibrin glue. The used ruthenium complex allowed inter- and intramolecular dityrosine binding of fibrinogen molecules. The advantage of this method is a one-step curing of fibrinogen via visible light that further achieved higher adhesive strengths than fibrin. In contrast to diazirine functionalization of cartilage, the ruthenium complex is of less toxicological concern. However, after in vitro cultivation of the disc/ring constructs, there was a decrease in integration strength. Compared to fibrin, a reduced cartilage synthesis was observed at the defect. It is also disadvantageous that a direct adjustment of the adhesive can only be made via protein concentration, since fibrinogen is a natural protein that has a fixed number of tyrosine binding sites without chemical modification. An additional cartilage adhesive was developed that is based on a mussel-inspired adhesive mechanism in which reactivity to a variety of substrates is enabled via free DOPA amino acids. DOPA-based adhesion is known to function in moist environments, a major advantage for application on water-rich cartilage tissue surrounded by synovial liquid. Reactive DOPA groups were synthetically attached to a polymer, here POx, to allow easy chemical modifiability, e.g. insertion of hydrolyzable ester motifs for tunable degradation. The possibility of preparing an adhesive hybrid hydrogel of POx in combination with fibrinogen led to good cell compatibility as was similarly observed with fibrin, but with increased immediate adhesive strength. Degradation could be adjusted by the amount of ester linkages on the POx and a direct influence of degradation rates on the development of integration in the in vitro model could be shown. Hydrogels are well suited to fill defect gaps and immediate integration can be achieved via adhesive properties. The results obtained show that for the success of long-term integration, a good ability of the adhesive to take up synthesized ECM components and cells to enable regeneration is required. The degradation kinetics of the adhesive must match the remodeling process to avoid intermediate loss of integration power and to allow long-term firm adhesion to the native tissue. Hydrogels are not only important as adhesives for smaller lesions, but also for filling large defect volumes and populating them with cells to produce tissue engineered cartilage. Many different hydrogel types suitable for cartilage synthesis are reported in the literature. A long-term stable fibrin formulation was tested in this work not only as an adhesive but also as a bulk hydrogel construct. Agarose is also a material widely used in cartilage tissue engineering that has shown good cartilage neosynthesis and was included in integration assessment. In addition, a synthetic hyaluronic acid-based hydrogel (HA SH/P(AGE/G)) was used. The disc/ring construct was adapted for such experiments and the inner lumen of the cartilage ring was filled with the respective hydrogel. In contrast to agarose, fibrin and HA-SH/P(AGE/G) gels have a crosslink mechanism that led to immediate bonding upon contact with cartilage during curing. The enhanced cartilage neosynthesis in agarose compared to the other hydrogel types resulted in improved integration during in vitro culture. This shows that for the long-term success of a treatment, remodeling of the hydrogel into functional cartilage tissue is a very high priority. In order to successfully treat larger cartilage defects with hydrogels, new materials with these properties in combination with chemical modifiability and a direct adhesion mechanism are one of the most promising approaches.},
  subject      = {Knorpel},
  language  = {en}
}
@phdthesis{Wagenbrenner2021,
  author    = {Wagenbrenner, Mike Helmut},
  title     = {In vitro-Charakterisierung mesenchymaler Stromazellen aus dem menschlichen H{\"u}ftgelenk},
  doi       = {10.25972/OPUS-23711},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-237110},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2021},
  abstract  = {In dieser Arbeit konnte erstmals gezeigt werden, dass plastik-adh{\"a}rent wachsende, multipotente Vorl{\"a}uferzellen, die eine f{\"u}r MSCs charakteristische Kombination von Oberfl{\"a}chenantigenen tragen, aus allen vier untersuchten Geweben des arthrotischen H{\"u}ftgelenks isoliert werden konnten. MSC-{\"a}hnliche Zellen k{\"o}nnen somit nicht nur in der Spongiosa und im Gelenkknorpel, sondern auch in der anterioren Gelenkkapsel und dem Ligamentum capitis femoris (LCF) des arthrotisch ver{\"a}nderten menschlichen H{\"u}ftgelenks nachgewiesen werden. Die FACS Analyse der Oberfl{\"a}chenantigene auf Zellen, die aus den vier unterschiedlichen Geweben eines beispielhaft gew{\"a}hlten Spenders isoliert wurden, zeigte eine deutliche Expression der Antigene CD44, CD73, CD90 und CD105. Unabh{\"a}ngig vom Nativgewebe zeigten somit alle untersuchten Zellen ein f{\"u}r MSCs charakteristisches, aber nicht spezifisches Profil an Antigenen auf ihrer Oberfl{\"a}che. Eine {\"U}bereinstimmung mit den ISCT Kriterien f{\"u}r MSCs war aufgrund der fehlenden Kontrolle h{\"a}matopoetischer Marker nicht m{\"o}glich. Die multipotente Differenzierung der isolierten Zellen erfolgte mithilfe spezifischer Differenzierungsmedien in Monolayer-Kulturen oder f{\"u}r die chondrogene Differenzierung in dreidimensionalen Pellet-Kulturen. Nach 21 Tagen konnten in allen differenzierten Kulturen histologisch und immunhistochemisch klare Zeichen der Osteo- und Adipogenese detektiert werden, w{\"a}hrend die Auswertung spezifischer Markergene eine klare Steigerung der Expression dieser im Vergleich zu den Negativkontrollen zeigte. Histologische und immunhistochemische Auswertungen best{\"a}tigten auch eine erfolgreiche chondrogene Differenzierung der Zell-Pellets aus Spongiosa, Knorpel und Kapsel. Lediglich in den chondrogen differenzierten Zell-Pellets aus dem LCF konnte immunhistochemisch keine Bildung des knorpelspezifischen Matrixproteins Col II nachgewiesen werden. Mikroskopisch zeigten vor allem die differenzierten MSC-Pellets aus Spongiosa und Knorpel morphologisch eine starke {\"A}hnlichkeit zu hyalinem Knorpelgewebe. Trotz dieser Abstufungen zeigten sich f{\"u}r die relative Expression der chondrogenen Markergene AGG, Col II und Sox-9 keine signifikanten Unterschiede zwischen den differenzierten MSC-Kulturen der vier unterschiedlichen Nativgewebe. Ein positiver Nachweis des Markers Col X wies nach 27 Tagen sowohl in differenzierten als auch in undifferenzierten Pellet-Kulturen auf eine leichte chondrogene Hypertrophie hin. Zusammenfassend zeigten sich keine signifikanten Unterschiede im Hinblick auf das osteogene und adipogene Differenzierungspotential aller untersuchten Zellen. W{\"a}hrend das chondrogene Differenzierungspotential der Zellen aus Spongiosa, Knorpel und Kapsel sich aus histologischer und immunhistochemischer Sicht {\"a}hnelte, zeigten Pellets aus dem LCF ein schw{\"a}cheres chondrogenes Differenzierungspotential in vitro. Obwohl somit erstmals MSC-{\"a}hnliche Zellen aus dem LCF und Gewebsproben, die neben dem Stratum synoviale auch das Stratum fibrosum der H{\"u}ftgelenkskapsel beinhalteten, charakterisiert wurden, sind weitere wissenschaftliche Arbeiten notwendig, um das multipotente Differenzierungspotential dieser Zellen zu optimieren.},
  subject      = {H{\"u}ftgelenk},
  language  = {de}
}
@phdthesis{Muelek2015,
  author    = {M{\"u}lek, Melanie},
  title     = {Distribution and metabolism of constituents and metabolites of a standardized maritime pine bark extract (Pycnogenol®) in human serum, blood cells and synovial fluid of patients with severe osteoarthritis},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128085},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {Dietary polyphenols have been related to beneficial effects on humans' health. Pycnogenol®, a dietary polyphenol-rich food supplement complies with the monograph "Maritime pine extract" in the United States Pharmacopeia (USP) and has demonstrated effects in different diseases. Several human trials concerning knee osteoarthritis have shown significant improvement of the symptoms like reducing the pain and the stiffness of the joint(s) upon intake of Pycnogenol®. After oral intake of multiple doses of Pycnogenol® previously low concentrations in the nanomolar range of monomeric extract constituents have been found in human plasma as well as a bioactive metabolite, δ-(3,4-dihydroxy-phenyl)-γ-valerolactone (M1), which is formed by the human intestinal flora from the procyanidins' catechin units. It is not clear yet which compound(s) of the complex extract is (are) mainly responsible for the described clinical effects of Pycnogenol®. To gain deeper insights into the in vivo fate of the pine bark extract the distribution of its constitutents and metabolites was closer investigated in the present thesis. Initial in vitro experiments suggested a facilitated cellular uptake of M1 into human erythrocytes, possibly via GLUT-1 transporter. For elucidating further the in vitro and in vivo metabolism of M1 in human blood cells, a metabolomic approach was performed using UPLC-ESI-qTOF-MSE analysis, which revealed a comprehensive and rapid metabolism of M1 to a variety of biotransformation products in human blood cells. Predominant metabolites were found to be conjugates of glutathione (GSH) isomers, namely M1-S-GSH and M1-N-GSH. Further sulfur-containing biotransformation products of M1 were conjugates with oxidized glutathione (M1-GSSG) and cysteine (M1-CYS) and the sulfated derivative of M1 (M1-sulfated). Other in vitro biotransformation products constituted the open-chained ester form of M1 (M1-COOH), hydroxybenzoic acid and the methylated (M1-methylated), acetylated (M1-acetylated), hydroxylated (M1-hydroxylated) and ethylated (M1-ethylated) derivatives of M1. Indeed, six of these in vitro metabolites, respectively M1-COOH, M1-sulfated, hydroxybenzoic acid, M1-S-GSH, M1-methylated and M1-acetylated, were also identified in vivo in blood cells of human volunteers after ingestion of Pycnogenol®. Related reference material was synthesized for reliable confirmation of the metabolites M1-GSH, M1-GSSG, M1-CYS and M1-COOH. In the course of a randomized controlled clinical trial patients suffering from severe osteoarthritis ingested multiple doses of 200 mg/day Pycnogenol® for three weeks before they were scheduled for an elective knee replacement surgery. Various biological specimen, respectively blood cells, synovial fluid and serum samples, were to be analyzed to investigate the distribution and disposition of possibly bioactive constituents and metabolites. Therefore, highly sensitive methods were developed using liquid chromatography tandem mass spectrometry (LC-MS/MS)- technology because of the expected low concentrations of the analytes in the related matrices. Initially, for each matrix different sample preparation techniques (protein precipitation, liquid-liquid extraction, solid phase extraction and useful combinations thereof) were compared to achieve maximum detection sensitivity of the analytes that were of highest interest, namely M1, ferulic acid and taxifolin. By comparing 32 various sample clean-up procedures in human serum, the highest recovery of the metabolite M1 was achieved using a liquid-liquid extraction with ethyl acetate and tert-butyl methyl ether at a serum pH-value of 3.2. A similar extraction method was also chosen for analyte detection in human synovial fluid after comparing 31 different sample preparation techniques. Whole blood or blood cells are difficult to handle because of their high viscosity and strong coloration. The QuEChERS (quick, easy, cheap, effective, rugged and safe) approach which was originally developed for the food safety and thus for the determination of pesticide residues in fruits and vegetables yielded the highest total recovery rate of M1 in human blood cells when assessing 18 different sample clean-up techniques. By applying the QuEChERS method for the first time for the simultaneous and highly sensitive quantification of selected polyphenols in human blood cells it was demonstrated that this fast and inexpensive technique can be applied in clinical fields for cleaning-up highly complex and thus challenging biological matrices. All developed methods for the different biological specimen were optimized to achieve maximum sensitivity of the target analytes. The determined lower limits of quantification (LLOQs) were sufficient for the quantification of the study samples. The LLOQs ranged from 113 pg/mL for taxifolin to 48 ng/mL for caffeic acid in blood cells and from 80 pg/mL for taxifolin to 3 ng/mL for caffeic acid in synovial fluid. In human serum the LLOQs even ranged down to 35 pg/mL for taxifolin and up to 8 ng/mL for caffeic acid. All analytical methods were subjected to a full validation according to current EMA and FDA guidelines and fulfilled those criteria, showing excellent performance and reliability of the developed and optimized methods. Serum, blood cells and synovial fluid samples of the osteoarthritis patients were all processed with an enzymatic incubation with ß-glucuronidase/sulfatase to hydrolyse conjugates (phase-II-metabolism) prior the actual sample preparation. Additionally, serum samples of the osteoarthritis patients were prepared without enzymatic hydrolysis to determine the individual degree of conjugation with sulfate and glucuronic acid of the analytes. All determined concentrations in the patients' samples were in the lower ng/mL range. Notably, highest total concentrations of the polyphenols were not detected in serum, in which the degree of analyte conjugation with sulfate and glucuronic acid ranged from 54.29 ± 26.77\% for catechin to 98.34 ± 4.40\% for M1. The flavonoids catechin and taxifolin mainly partitioned into blood cells, whereas the metabolite M1, ferulic and caffeic acid primarily resided in the synovial fluid. The concentration of M1 in the blood cells was low, however, this could be explained by the previously observed extensive and rapid intracellular metabolism in vitro. This was now supported by the in vivo evidence in samples of patients who received Pycnogenol® in which the open-chained ester form of M1 (M1-COOH) as well as the glutathione conjugate of M1 (M1-GSH) were identified, indicating that M1 does not accumulate in its original form in vivo. Possibly, a variety of bioactive metabolites exist which might play an important role for the clinical effects of Pycnogenol®. Although the study participants were requested to avoid polyphenol-rich food and beverages within the last two days before the blood samplings this was obviously difficult for most of the patients. Hence, no statistically significantly difference was observed in the mean polyphenol concentrations in serum, blood cells and synovial fluid between the intervention and the control group. Nevertheless, it was possible to identify marker compounds for Pycnogenol® intake under real life conditions with occasional or regular consumption of polyphenol-rich foods and beverages. Thereby, ferulic acid was found in serum samples exclusively after intake of Pycnogenol®, confirming that ferulic acid is a suitable marker of consumption of French maritime pine bark extract. Taxifolin was present in serum and synovial fluid exclusively in the intervention group indicating a role as further marker of Pycnogenol® intake. Taxifolin, ferulic acid and caffeic acid were detected in both serum and synovial fluid only in the intervention group. Moreover, the metabolite M1, taxifolin and ferulic acid were only detected simultaneously in all matrices (serum, blood cells and synovial fluid) after ingestion of Pycnogenol®. Thus, deeper insights into the distribution of bioactive constituents and metabolites of Pycnogenol® into serum, blood cells and synovial fluid after oral administration to patients with severe osteoarthritis were gained. The present study provides the first evidence that polyphenols indeed distribute into the synovial fluid of patients with osteoarthritis where they might contribute to clinical effects.},
  subject      = {Pycnogenol},
  language  = {en}
}
@phdthesis{Lavorante2015,
  author    = {Lavorante, Jochen},
  title     = {Resektionsarthroplastik versus Arthrodese des Daumensattelgelenkes bei jungen, handwerklich t{\"a}tigen Patienten mit Rhizarthrose},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-121462},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2015},
  abstract  = {In der vorliegenden Studie zeigten sich wesentlich bessere Ergebnisse f{\"u}r die Resektionsarthroplastik als f{\"u}r die Arthrodese des Sattelgelenkes bei der Behandlung von jungen, handwerklich t{\"a}tigen Patienten mit Rhizarthrose. Deshalb kann bei diesen Patienten der Resektionsarthroplastik eindeutig der Vorzug gegen{\"u}ber der Arthrodese gegeben werden. Die Resektionsarthroplastik stellt eine gute Behandlungsoption dar und liefert vorhersagbare Ergebnisse, die sich weitgehend mit denen nach Behandlung von „normalen", typischen Rhizarthrose-Patienten decken. Die Einsch{\"a}tzung des Stellenwertes der Arthrodese ist deutlich schwieriger. Aufgrund der teilweise gegens{\"a}tzlichen Ergebnisse und Einsch{\"a}tzungen anderer Publikationen m{\"u}ssen die relativ schlechten Ergebnisse der vorliegenden Studie relativiert werden. Somit kann nicht generell von der Durchf{\"u}hrung von Arthrodesen des Daumen-sattelgelenkes abgeraten werden. Die Ergebnisse nach Arthrodesen haben jedoch eine gr{\"o}ßere Schwankungsbreite und sind wahrscheinlich in h{\"o}herem Maße von technischen Details und von der Erfahrung des Operateurs abh{\"a}ngig. Die Durchf{\"u}hrung einer Arthrodese kann eine sinnvolle Alternative f{\"u}r Operateure sein, die ausreichende Erfahrung mit diesem Verfahren haben. Operateuren, die keine oder wenig Erfahrung mit der Durchf{\"u}hrung von Arthrodesen haben, kann dieses Verfahren kaum empfohlen werden, sie k{\"o}nnen mit einer Resektionsarthroplastik wahrscheinlich bessere Ergebnisse erzielen.},
  subject      = {Rhizarthrose},
  language  = {de}
}
@phdthesis{Waetzig2010,
  author    = {W{\"a}tzig, Christine},
  title     = {Klinische Ergebnisse der Schulterendoprothetik bei Patienten mit Erkrankungen aus dem rheumatischen Formenkreis im Vergleich zu Patienten mit degenerativ bedingter Omarthrose},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-47566},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {Im Rahmen dieser retrospektiven Studie wurden 23 Patienten mit Erkrankungen aus dem rheumatischen Formenkreis, {\"u}berwiegend rheumatoide Arthritis und 22 Kontrollpersonen mit degenerativ bedingter Omarthrose, welchen zwischen 1993 und 2005 eine Schulterendoprothese unterschiedlichen Typs implantiert worden war, durchschnittlich 28 Monate postoperativ klinisch und radiologisch nachuntersucht. Das Alter zum Zeitpunkt der Operation betrug im Mittel 65 Jahre. Die Ergebnisse wurden anhand des Constant Score erhoben. Durch die Operation verbesserten die 23 Patienten mit Erkrankungen aus dem rheumatischen Formenkreis ihren Constant Score von durchschnittlich 21,7\% auf 79,9\%. Die Kontrollgruppe wies sowohl pr{\"a}operativ (28,7\%) als auch postoperativ (96,3\%) eine signifikant bessere Schulterfunktion auf. Innerhalb beider Kollektive waren ca. 95\% der Patienten mit dem Operationsergebnis sehr zufrieden bzw. zufrieden.},
  subject      = {Rheumatoide Arthritis},
  language  = {de}
}
@phdthesis{Jahn2008,
  author    = {Jahn, Sandra},
  title     = {Ergebnisse des Oberfl{\"a}chenersatzes nach Copeland bei jungen Patienten mit Omarthrosen unterschiedlicher Genese},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-27776},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2008},
  abstract  = {Im Rahmen dieser retrospektiven Studie wurden 29 Patienten (Durchschnittsalter 49,8 Jahre, Follow-up im Mittel nach 15,7 Monaten), die mit dem Oberfl{\"a}chenersatz nach Copeland versogt wurden, klinisch und mit bildgebenden Maßnahmen untersucht. Die Zielvariablen waren der Constant-Score und eine metrische Analyse der postoperativen Implantatlage (humorales Offset und Overstuffing). Es zeigte sich bei allen Patienten eine signifikante Verbesserung der Schulterfunktion. Der pr{\"a}operative Constant-Score von 22,4 Punkten (27,2\% im altersadaptierten Score) wurde auf 47,6 Punkte (57,6\% im altersadaptierten Score) postoperativ signifikant gesteigert. Deutliche und statistisch signifikante Verbesserungen konnten in allen Bereichen des Constant Scores erreicht werden, wobei die Kategorie Schmerz am st{\"a}rksten und die Kategorie Kraft am geringsten profitiert. Es zeigte sich bei der metrischen Analyse eine gute Rekonstruktion der Anatomie. Eine signifikante Korrelation des postoperativen Offsets und Radius mit dem postoperativen Constant-Score wurde nicht beobachtet. Die besten Ergebnisse waren bei den avaskul{\"a}ren Humeruskopfnekrosen und den Instabilit{\"a}tsarthropathien zu finden. Im Vergleich zu anatomischen Totalendoprothesen und inversen Modellen bringt der Oberfl{\"a}chenersatz des Humeruskopfes schlechtere funktionelle Ergebnisse bei {\"a}hnlich guter Schmerzreduktion. Der Vorteil liegt in einer wesentlich besseren Erhaltung der Knochensubstanz und im Falle von Komplikationen in g{\"u}nstigeren Revisionsm{\"o}glichkeiten.},
  subject      = {Schultergelenk},
  language  = {de}
}
@phdthesis{Eden2005,
  author    = {Eden, Lars},
  title     = {Bedeutung von DNS-Polymorphismen bei Arthrose},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-16996},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2005},
  abstract  = {Arthrose ist eine Erkrankung des Gelenks, die einen erheblichen Einfluss auf die Lebensqualit{\"a}t der Betroffenen sowie auch auf die Volkswirtschaft eines Landes hat. Das Kniegelenk ist das dabei am h{\"a}ufigsten befallene Gelenk. Leider gibt es bis zum heutigen Tag keine kausale, kurative Therapie dieser Erkrankung. In Fr{\"u}hstadien kann der Verlauf im Idealfall gestoppt werden, in Sp{\"a}tstadien ist h{\"a}ufig der k{\"u}nstliche Gelenkersatz die einzige Therapieoption, die Aussicht auf Schmerzfreiheit und einen gewissen Funktionserhalt gew{\"a}hrleisten kann. Lange Zeit war man der Meinung, dass die Arthrose eine logische Konsequenz des Alterns sei. Zuletzt geht man jedoch mehr und mehr davon aus, dass die Arthrose ein komplexes Zusamenspiel aus Entz{\"u}ndung, mechanischen Kr{\"a}ften, zellul{\"a}ren und biochemischen Prozessen sowie nicht zuletzt der Genetik ist. Die Genetik wurde in dieser Studie zum Fokus des Interesses gemacht, als ein entscheidender Faktor der prim{\"a}ren Arthrose. Untersucht wurden Polymorphismen in entscheidenden Regionen (Promoter, Exons) von Genen, die im Arthrose-Prozess eine große Bedeutung haben: Il-1 alpha, Il-1 beta, TNF alpha und MMP-3 (Stromelysin). Viele bereits durchgef{\"u}hrte Studien lieferten widerspr{\"u}chliche Ergebnisse, wiesen zu geringe Fallzahlen auf oder definierten die Kollektive nur unzureichend. Ziel dieser Studie war es klar definierte Kollektive mit m{\"o}glichst extremen Zust{\"a}nden gegen{\"u}berzustellen. Junge bereits in fr{\"u}hen Jahren an Arthrose Erkrankte (<45 Jahre) sollten gesunden Patienten {\"u}ber 55 Jahre gegen{\"u}bergestellt werden. Als dritte Gruppe dienten Altersarthrotiker. Die Diagnosen wurden arthroskopisch gestellt, der Zielwert pro Gruppe sollte 100 Patienten betragen. F{\"u}r die Auswertung wurden etablierte Verfahren wie die PCR, Restriktion und der Gensequencer genutzt. Die Allelverteilungen der Polymorphismen TNF alpha und MMP-3 konnten in der Auswertung zwischen den Gruppen keinen signifikanten Unterschied aufweisen. Das legt nahe, dass diese beiden Polymorphismen wohl keinen Einfluss auf die Entstehung von Arthrose haben. Bei Il-1 alpha und Il-1 beta wurden keine eindeutigen Ergebnisse erzielt. Es deutet sich ein Trend an, dass diese beiden Polymorphismen einen Einfluss haben, der allerdings erst durch eine h{\"o}here Fallzahl best{\"a}tigt bzw. widerlegt werden k{\"o}nnte. Ziel weiterer Untersuchungen sollte es ebenso sein, die bestehende bzw. die in der Fallzahl erh{\"o}hte DNS-Bank auf weitere Polymorphismen von Genen, die im Arthroseprozess eine Rolle spielen (z.B. Il-1 ra, weitere MMPs, TIMP etc.), zu untersuchen. Interessant k{\"o}nnte auch die Kombination einzelner Varianten innerhalb eines Genclusters sein, entsprechend dem Beispiel von Smith, A.J. et al. 2004 bei einem Il-1 R1-Il-1 alpha -Il-1 beta-Il-1 RN Gencluster. Sicherlich bedarf es noch viel intensiver Forschung, um das komplexe Zusammenspiel der einzelnen Faktoren im Arthroseprozess zu verstehen, um so die einzelnen Mosaiksteinchen innerhalb des Gesamtkomplexes darzustellen. Jedoch l{\"a}sst sich nur auf diese Weise das Ziel erreichen, eines Tages diese multifaktorielle Erkrankung zu verstehen und zu heilen.},
  language  = {de}
}