Bernd Baumann

University of Wuerzburg, Würzburg, Bavaria, Germany

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Publications (27)32.25 Total impact

  • The Journal of Bone and Joint Surgery 04/2011; 93(7):e29. · 3.23 Impact Factor
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    ABSTRACT: The aim of this study was to examine whether depression is a strong predictor of elevated postoperative pain levels following orthopedic surgery and whether the implementation of standardized pain management is more beneficial for patients with depression. We performed a non-randomized, prospective study with two different groups of patients who underwent orthopedic surgery. Group 1 (n=249) received non-standardized pain therapy whereas group 2 (n = 243) was treated with a standardized pain management concept. Effects of the treatment were monitored with a VAS-based pain assessment protocol. Depression was measured preoperatively with the self-reported Patient Health Questionnaire (PHQ-9). Patients with the probable diagnosis of a current episode of major depression showed significantly higher postoperative pain than patients without a depressive episode. On the other hand, patients with depression benefited from the implementation of standardized pain management. Our data suggest a predictive value of depression for severe postoperative pain. Patients with depression benefited from standardized postoperative pain therapy, but were still suffering from significantly higher postoperative pain.
    Der Schmerz 02/2010; 24(1):54-61. · 1.02 Impact Factor
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    ABSTRACT: Ziel unserer Arbeit war es, die Prädiktionskraft von Depression im Hinblick auf die postoperative Schmerzsymptomatik bei orthopädischen Patienten zu untersuchen. In einem zweiten Schritt wurde die Wirksamkeit der Implementierung einer standardisierten Schmerztherapie auf den Schmerzverlauf bei depressiven Patienten im Vergleich zu Patienten ohne Depression untersucht. Es wurden 492Patienten, bei denen eine orthopädische Operation durchgeführt wurde, in diese prospektive Verlaufsbeobachtung eingeschlossen. Alle Patienten wurden präoperativ mit der deutschen Version des Patient Health Questionnaire (PHQ-9) zur Erfassung depressiver Symptomatik untersucht. Gruppe1 (n=249) erhielt eine unsystematische, individuelle und indikationsspezifische Schmerztherapie, Gruppe2 (n=243) erhielt eine standardisierte Schmerztherapie. Patienten mit einer präoperativ bestehenden depressiven Symptomatik hatten ein signifikant höheres postoperatives Schmerzempfinden als Patienten ohne Depression und profitierten mehr von der Implementierung einer standardisierten Schmerztherapie. Unsere Daten zeigen eine höhere Wahrscheinlichkeit für depressive Patienten, an postoperativen Schmerzen zu leiden. Sie profitieren zudem stärker von der Implementierung eines standardisierten Schmerztherapiekonzepts als Patienten ohne Depression, zeigen jedoch im Vergleich weiterhin ein signifikant höheres Schmerzniveau. The aim of this study was to examine whether depression is a strong predictor of elevated postoperative pain levels following orthopedic surgery and whether the implementation of standardized pain management is more beneficial for patients with depression. We performed a non-randomized, prospective study with two different groups of patients who underwent orthopedic surgery. Group 1 (n=249) received non-standardized pain therapy whereas group 2 (n = 243) was treated with a standardized pain management concept. Effects of the treatment were monitored with a VAS-based pain assessment protocol. Depression was measured preoperatively with the self-reported Patient Health Questionnaire (PHQ-9). Patients with the probable diagnosis of a current episode of major depression showed significantly higher postoperative pain than patients without a depressive episode. On the other hand, patients with depression benefited from the implementation of standardized pain management. Our data suggest a predictive value of depression for severe postoperative pain. Patients with depression benefited from standardized postoperative pain therapy, but were still suffering from significantly higher postoperative pain. SchlüsselwörterPostoperative Schmerzen-Depression-PHQ-9-Postoperative Schmerztherapie-Orthopädische Operation KeywordsDepression-Postoperative pain-Pain therapy-PHQ-9-Orthopedic surgery
    Der Schmerz 01/2010; 24(1):54-61. · 1.02 Impact Factor
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    ABSTRACT: This study retrospectively analyzed 1007 diagnostic shoulder arthroscopies. The study included 72 patients with an arthroscopically verified pulley lesion as the main pathologic finding. Epidemiologic data and arthroscopic findings were evaluated in all patients, and 53 were clinically examined with the Constant score after a minimum follow-up of 2 years. We observed an incidence of 7.1% for pulley lesions. An isolated rupture of the superior glenohumeral ligament (SGHL) was seen in 53 patients (73.6%) and a combined partial articular-side tear of the rotator cuff adjacent to rotator interval in 19 (26.4%). Thirty-one patients (43%) had a history of trauma, whereas 41 (57%) had none. Overall, the mean postoperative Constant score adjusted for age and gender was 80.1% (range, 47%-135%). Patients with a SGHL lesion only (85.7%) exhibited a significant (P = .047) higher age- and gender-adjusted Constant score compared with patients with a combined partial surface tendon tear (73.1%). Our epidemiologic data accentuate the need for careful evaluation of the superolateral aspect of rotator interval to avoid underdiagnosis of pulley lesions at shoulder arthroscopy. Our findings provide evidence that the clinical outcome of isolated SGHL lesions is better compared with combined partial articular-side rotator cuff tear. With respect to the progressive pathologic process of pulley lesions, we recommend an early surgical treatment.
    Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.] 01/2008; 17(1):14-20. · 1.93 Impact Factor
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    ABSTRACT: The chondrogenic differentiation of bone marrow-derived human mesenchymal stem cells (MSCs) in a collagen type I hydrogel, which is in clinical use for matrix-based autologous chondrocyte transplantation (ACT), was investigated. Collagen hydrogels with 2.5 x 10(5) MSCs/mL were fabricated and cultured for 3 weeks in a serum-free, defined, chondrogenic differentiation medium containing 10 ng/mL TGF-beta1 or 100 ng/mL BMP-2. Histochemistry revealed morphologically distinct, chondrocyte-like cells, surrounded by a sulfated proteoglycan-rich extracellular matrix in the TGF-beta1 and BMP-2 treated group, with more elongated cells seen in the BMP-2 treated group. Immunohistochemistry detected collagen type II (Col II) in the TGF-beta1 and BMP-2 treated group. Collagen type X (Col X) staining was positive in the TGF-beta1 but only very weak in the BMP-2 treated group. RT-PCR analyses revealed a specific chondrogenic differentiation with the expression of the cartilage specific marker genes Col II, Col X, and aggrecan (AGN) in the TGF-beta1 and the BMP-2 treated group, with earlier expression of these marker genes in the TGF-beta1 treated group. Interestingly, MSC-gels cultured in DMEM with 10% FBS (control) indicated few isolated chondrocyte-like cells but no expression of Col II or Col X could be detected. The results show, that MSCs cultured in a collagen type I hydrogel are able to undergo a distinct chondrogenic differentiation pathway, similar to that described for MSCs cultured in high-density pellet cultures. These findings are valuable in terms of ex vivo predifferentiation or in situ differentiation of MSCs in collagen hydrogels for articular cartilage repair.
    Journal of Biomedical Materials Research Part A 01/2008; 83(3):626-35. · 2.83 Impact Factor
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    ABSTRACT: This retrospective study reviewed 9- to 11-year results after total hip arthroplasty (THA) with cemented titanium stems (Mueller-Straight-Stem). Ninety-one patients (110 hips) were examined clinically and radiologically at an average 9.5-year follow-up. Revisions for aseptic loosening were performed in 4 (4%) patients. Subsidence or varus position could only be observed in one of these patients. Radiolucent lines were found in 37 patients, mainly located around the proximal zones of the stem (zone 1, 7, 8, and 14). Harris scores were good or excellent in 78% and satisfactory in 20% of patients. The 9.5-year survival rate of the cemented titanium stem with regard to aseptic loosening was 96.4%. Body weight was significantly higher (88 +/- 5.4 kg) in the 4 patients with aseptic loosening, compared to patients without radiolucent lines (75 +/- 15 kg). The body weight to stem surface ratio showed a significant difference (1.5 kg/cm2 versus 1 kg/cm2; P < .05). No significant differences were found in other factors, including sex, size or type of stem, Harris score, heterotopic ossification, or body mass index. Good long-term results can be achieved with cemented titanium stem implants. This titanium implant is recommended for patients with hypersensitivity to chrome, cobalt, and nickel. mplanting the biggest possible stem seems to be most beneficial.
    Orthopedics 07/2007; 30(7):551-7. · 1.05 Impact Factor
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    ABSTRACT: Tumor necrosis factor alpha (TNFalpha) plays a fundamental role in the pathogenesis of wear particle-induced periprosthetic osteolysis. However, particle-induced mechanisms that control TNFalpha gene expression are not yet well characterized. LITAF [lipopolysaccharide (LPS)-induced TNFalpha factor] is a novel transcription factor that regulates expression of the TNFalpha gene, but nothing is known about its role in wear particle-induced osteolysis. We evaluated the effect of titanium aluminum vanadium (TiAlV) and polyethylene particles on mRNA expression of LITAF. A human monocytic leukemia cell line (THP-1) was used in this in vitro study. THP-1 monocytes were differentiated to macrophage-like cells and exposed to LPS-detoxified polyethylene particles and prosthesis-derived TiAlV particles. Supernatant was used for TNFalpha protein measurement and total RNA was extracted from cells. LITAF was analyzed at the mRNA level using semiquantitative RT-PCR. Both polyethylene and TiAlV particles induced significant upregulation of LITAF mRNA that was followed by a significant TNFalpha response. These effects were dependent on the particle dose. Low particle concentrations exhibited no significant effect on expression of TNFalpha and LITAF mRNA. In comparison to exposure to polyethylene and TiAlV particles, LPS stimulation exhibited similar upregulation of LITAF mRNA, but led to an overwhelming TNFalpha response. Our findings provide evidence that LITAF is implicated in the pathogenesis of wear particle-induced osteolysis.
    Biomedizinische Technik 02/2007; 52(2):200-7. · 1.16 Impact Factor
  • Journal of Biomedical Materials Research Part A 01/2007; · 2.83 Impact Factor
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    ABSTRACT: TNFalpha is a potent osteoclastogenic cytokine that has a fundamental role in the pathogenesis of wear particle-induced osteolysis. Wear particles of one composition and their biological effects are well characterised. In contrast, little is known about the effects of mixed particles with respect to mix ratio and particle concentration. We evaluated the effects of different mix ratios of polyethylene and TiAlV particles on TNFalpha response. We used a human monocytic cell line (THP-1) in this in vitro study. THP-1 monocytes were differentiated to macrophage-like cells and exposed to different mixtures of lipopolysaccharide-detoxified polyethylene and TiAlV particles. TNFalpha was analysed in culture supernatants using ELISAs. Both polyethylene and TiAlV particles induced a dose- and time-related release of TNFalpha, with maximum levels after 6 h. A PE/TiAlV mix ratio of 36:1 at 10(8) particles/ml induced significantly higher TNFalpha concentrations compared to equal particle concentrations of isolated TiAlV (p=0.047) or PE (p=0.044), indicating the synergistic effect of mixed particles. These results provide evidence that TiAlV and polyethylene particles have significant synergistic effects, depending on the mix ratio and particle concentrations. This supra-additive effect can contribute substantially to the pathogenesis of implant particle-induced osteolysis.
    Biomedizinische Technik 02/2006; 51(5-6):360-6. · 1.16 Impact Factor
  • Zeitschrift Fur Orthopadie Und Ihre Grenzgebiete - Z ORTHOP GRENZGEB. 01/2006; 144(5):519-523.
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    ABSTRACT: StudienzielDie zunehmende Inzidenz von Rotatorenmanschettendefekten (RMD) mit steigendem Alter stellt den Schulterchirurgen immer häufiger vor die Entscheidung, ob denn auch beim älteren Patienten eine Rekonstruktion sinnvoll und zu empfehlen ist. Anhand einer retrospektiven Analyse soll die Frage geklärt werden, inwieweit sich die klinischen Ergebnisse nach offener Rekonstruktion eines RMD, die Defektgröße, Begleitpathologien und Redefektrate bei Patienten ab dem sechzigsten Lebensjahr von denen jüngerer Patienten unterscheiden. MethodeBei 76 Patienten mit einem Durchschnittsalter von 65 Jahren (60–78 Jahre) und bei 166 Patienten unter 60 Jahren wurde eine Rekonstruktion eines Rotatorenmanschettendefektes durchgeführt. Es erfolgte eine genaue Analyse aller intraoperativ erhobenen Befunde hinsichtlich der Rupturgröße, Affektionen des Acromioclavicular-Gelenks (ACG) und der langen Bizepssehne (LBS). Nach einem Follow-up von mindestens 2 Jahren wurde der Constant-Score erhoben sowie eine klinische und sonographische Nachuntersuchung durchgeführt. ErgebnisseDie beiden Gruppen unterschieden sich hinsichtlich der intraoperativ gefundenen Rupturgröße (p=0,591) und der Häufigkeit kompletter LBS-Rupturen (p=0,61) sowie der Häufigkeit der sonographisch gefundenen Redefekte (p=0,341) nicht signifikant. Jedoch hatten die Patienten ab 60 Jahren mit einem durchschnittlichen alters- und geschlechtskorrigierten Constant-Score von 90% (13–126%) signifikant bessere Werte (p=0,002) als die Gruppe unter 60 Jahren mit 81,1% (15–116%). Bei den Patienten ab 60 fanden sich signifikant häufiger therapierelevante Affektionen des ACG (p<0,001) und der LBS (p=0,002). SchlussfolgerungDiese Daten zeigen für beide Gruppen keine signifikanten Unterschiede der Defektgröße, LBS-Rupturen und der Rate an Rezidivdefekten. Das ACG und die LBS waren mit zunehmendem Alter signifikant häufiger betroffen. Überraschenderweise war der Constant-Score bei den älteren Patienten signifikant besser. Diese Ergebnisse zeigen, dass eine Rekonstruktion der Rotatorenmanschette auch bei älteren Patienten gute Ergebnisse liefert und daher ein höheres Lebensalter keine Kontraindikation zur OP darstellen sollte. Bereits im Vorfeld sollte ein besonderes Augenmerk auf das ACG und die LBS gerichtet werden. AimThe patient’s age has been described as one factor having a large influence on the success of rotator cuff surgery. With this retrospective study the relevance of the patient’s age (below 60 compared to 60 and older) on the functional and structural outcome of open rotator cuff repairs and the difference in defect size, affections of the acromioclavicular joint (ACJ) and the long head of biceps (LHB) was analysed. MethodGroup 1 consisted of 76 patients, 60 years and older (60–78 years), while group 2 of 166 patients below 60 years,who were reassessed after a minimum follow-up of 2 years after open rotator cuff repair. Intraoperatively the tear size, affections of the ACJ and LHB were recorded. The postoperative examination protocol included clinical and sonographical assessment and the evaluation of the Constant score. ResultsRegarding tear size (p=0.591), complete LHB ruptures (p=0.61) and re-tears verified by follow-up ultrasonography (p=0341) no significant differences were found. The age- and gender-adapted Constant score of group 1 (90 %) was significantly (p=0.002) better than in group 2 (81.1 %). In group 1 the ACJ (p<0.001) and LHB (p=0.002) were found to have a significantly higher rate of relevant pathologic changes. ConclusionOur data demonstrate no significant differences regarding the tear-size, LHB-ruptures or postoperative rate of re-tears between both groups. But the average age and gender adapted Constant-score in patients 60 years and older was significantly higher than in patients below 60 years. Therefore the age of a patients should not be the main criterion to determine the therapy for patients with rotator cuff tears. As the ACG and LHB had a significantly higher rate of relevant pathologies with increasing age, a sorrow pre- and intraoperative assessmenr is mandatory.
    Obere Extremität 01/2006; 1(1):2-7.
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    ABSTRACT: In literature there are only few data which describe the influence of occupation on the development of rotator cuff disease. In a retrospective study, 760 open rotator cuff repairs were analysed and related to the profession and occupational load. Exclusion criteria were traumatic tears and sports injuries. All male persons were statistically analysed and the data compared with occupational patterns of the region, obtained from the Federal Statistical State Office. Rotator cuff repairs were performed in 472 males who had no evidence for a traumatic origin. After statistical analysis (p < 0.001) we found significantly more patients working in agriculture and forestry (6.38% versus 1.07% in Bavaria) and in the building industry (35.11% versus 13.40% in Bavaria). Our data suggest that working exposure increases the risk or leads to the clinical manifestation of rotator cuff tears. Although a detailed analysis of individual physical exposure is not available yet, the statistical results indicate that rotator cuff tears must be taken into consideration as a result of ergonomic exposure.
    Zeitschrift für Orthopädie 01/2006; 144(5):519-23. · 0.86 Impact Factor
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    ABSTRACT: Wear particles are believed to induce periprosthetic inflammation which contributes to periprosthetic osteolysis. TNFalpha plays a pivotal role in the pathogenesis of this process. The molecular mechanisms leading to the development of periprosthetic inflammation with upregulated TNFalpha expression in monocytic cells in response to different wear particles have yet to be defined. In this study we evaluated the effects of polyethylene- and TiAlV-particles on activation of NF-kappaB signalling pathways and TNFalpha biosynthesis and release in monocytic cells with respect to periprosthetic osteoclastogenesis. THP-1 monocytic cells were differentiated to macrophage-like cells and exposed to LPS-detoxified polyethylene and prosthesis-derived TiAlV-particles. TNFalpha release was analyzed in culture supernatant by ELISA. NF-kappaB activation was examined by electrophoretic mobility shift assay (EMSA), and NF-kappaB target promoter activities including transactivation of the TNFalpha promoter were determined by luciferase reporter gene assays. Differentiated THP-1 macrophages were exposed to increasing numbers of particles for 0, 60, 180 and 360 min. Both, polyethylene- and TiAlV-particles induced a significant activation of both NF-kappaB and TNFalpha promoters at 180 min. A significant TNFalpha release was detected after 360 min exposure to polyethylene- and TiAlV-particles in a dose dependent manner. In comparison, LPS induced a much greater activation of NF-kappaB and TNFalpha promoters, and TNFalpha secretion into the supernatant was strongly induced. These results provide evidence that induction of the NF-kappaB signal transduction pathway in macrophages plays a major role in initiating and mediating the inflammatory response leading to periprosthetic osteolysis.
    Journal of Orthopaedic Research 12/2005; 23(6):1241-8. · 2.88 Impact Factor
  • Journal of Orthopaedic Research 11/2005; · 2.88 Impact Factor
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    ABSTRACT: Disruptions of the anterior cruciate ligament (ACL) of the knee joint are common and are currently treated using ligament or tendon grafts. In this study, we tested the hypothesis that it is possible to fabricate an ACL construct in vitro using mesenchymal stem cells (MSC) in combination with an optimized collagen type I hydrogel, which is in clinical use for autologous chondrocyte transplantation (ACT). ACL constructs were molded using a collagen type I hydrogel containing 5 x 10(5) MSC/mL and non-demineralized bone cylinders at each end of the constructs. The constructs were kept in a horizontal position for 10 days to allow the cells and the gel to remodel and attach to the bone cylinders. Thereafter, cyclic stretching with 1 Hz was performed for 14 days (continuously for 8 h/day) in a specially designed bioreactor. Histochemical analysis for H and E, Masson-Goldner and Azan and immunohistochemical analysis for collagen types I and III, fibronectin and elastin showed elongated fibroblast-like cells embedded in a wavy orientated collagenous tissue, together with a ligament-like extracellular matrix in the cyclic stretched constructs. No orientation of collagen fibers and cells, and no formation of a ligament-like matrix, could be seen in the non-stretched control group cultured in a horizontal position without tension. RT-PCR analysis revealed an increased gene expression of collagen types I and III, fibronectin and elastin in the stretched constructs compared with the non-stretched controls. In conclusion, ACL-like constructs from a collagen type I hydrogel, optimized for the reconstruction of ligaments, and MSC have been fabricated. As shown by other investigators, who analyzed the influence of cyclic stretching on the differentiation of MSC, our results indicate a ligament-specific increased protein and gene expression and the formation of a ligament-like extracellular matrix. The fabricated constructs are still too weak for animal experiments or clinical application and current investigations are focusing on the development of a construct with an internal augmentation using biodegradable fibers.
    Cytotherapy 02/2005; 7(5):447-55. · 3.06 Impact Factor
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    ABSTRACT: Informations about wear particles in metallosis (mode II wear) and their effects in vitro and in vivo are limited. The aim of this study was to characterize wear particles obtained intraoperatively and to analyse their effects on cytokine response in an established human macrophage-like cell culture model. Wear particles were obtained intraoperatively from four patients with metallosis resulting from CrCoMo/PE/TiAIV-implants (mode II wear) (3 knee, 1 hip prosthesis). After purification, particles were characterized regarding to their composition and size (particle size analyser, electron microscopy, edx-analysis, histological slices). The effects of particles on the release of cytokines (PDGF, IL-1beta, IL-8, TNF alpha) were determined in an established human macrophage-like cell culture system by ELISA-assays. The metal wear particles consisted of TiAIV with a mean size of 0.1 +/- 0.15 microm, independent of the prosthesis location. CrCoMo particles could not be detected. In the cell culture model 1456 x 10(8) particles per 1 x 10(6) macrophages released maximum amounts of TNFalpha (8-fold) and IL-8 and IL-1beta (5-fold) while the survival rate of the cells was more than 90 percent. A particle-dependent increase of PDGF-levels could not be detected. As already shown for mode I wear particles (contact between primary bearing surfaces), also mode II wear particles cause release of bone resorbing cytokines in a macrophage-like cell culture model. Because their local and systemic effects in vivo are still not completely understood, we recommend a complete removal of wear particles in cases of metallosis to avoid possible immunological reactions of the body as well as periprosthetic osteolysis.
    Biomedizinische Technik 01/2005; 50(1-2):25-9. · 1.16 Impact Factor
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    ABSTRACT: Wear particles are believed to induce periprosthetic inflammation which contributes to periprosthetic osteolysis. TNFα plays a pivotal role in the pathogenesis of this process. The molecular mechanisms leading to the development of periprosthetic inflammation with upregulated TNFα expression in monocytic cells in response to different wear particles have yet to be defined. In this study we evaluated the effects of polyethylene- and TiAlV-particles on activation of NF-κB signalling pathways and TNFα biosynthesis and release in monocytic cells with respect to periprosthetic osteoclastogenesis. THP-1 monocytic cells were differentiated to macrophage-like cells and exposed to LPS-detoxified polyethylene and prosthesis-derived TiAlV-particles. TNFα release was analyzed in culture supernatant by ELISA. NF-κB activation was examined by electrophoretic mobility shift assay (EMSA), and NF-κB target promoter activities including transactivation of the TNFα promoter were determined by luciferase reporter gene assays. Differentiated THP-1 macrophages were exposed to increasing numbers of particles for 0, 60, 180 and 360min. Both, polyethylene- and TiAlV-particles induced a significant activation of both NF-κB and TNFα promoters at 180min. A significant TNFα release was detected after 360min exposure to polyethylene- and TiAlV-particles in a dose dependent manner. In comparison, LPS induced a much greater activation of NF-κB and TNFα promoters, and TNFα secretion into the supernatant was strongly induced. These results provide evidence that induction of the NF-κB signal transduction pathway in macrophages plays a major role in initiating and mediating the inflammatory response leading to periprosthetic osteolysis.
    Journal of Orthopaedic Research 01/2005; 23(6):1241-1248. · 2.88 Impact Factor
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    ABSTRACT: Wear debris has been associated with periprosthetic osteolysis and loosening of total joint arthroplasties. RANKL (receptor activator of NF-kappaB ligand), RANK (receptor activator of NF-kappaB) and OPG (osteoprotegerin) are three key molecules which regulate differentiation, survival, fusion, and activation of osteoclasts. We evaluated the effect of TiAIV and polyethylene particles on expression of RANK, RANKL and OPG mRNA. We used a human monocytic leukemic cell line (THP-1) in this in vitro study. THP-1 monocytes were differentiated into macrophage-like cells and exposed to polyethylene particles and prosthesis-derived TiAIV particles. The supernantant was used for measurement of TNFalpha protein and total RNA was extracted from the cells. Expression of the genes coding for OPG, RANKL and RANK was analysed at the mRNA level using a semiquantitative RT-PCR method. Both polyethylene and TiAIV particles induced a significant release of TNFalpha after 6 h of exposure and a significant upregulation of RANK mRNA. OPG mRNA expression was transiently upregulated after exposure to polyethylene and TiAIV particles. These effects were dependent on particle dose. RANKL mRNA was not detectable in our THP-1 model. In contrast, LPS exhibited a different pattern of RANK/ RANKL/OPG mRNA expression. Our findings provide evidence that both polyethylene and TiAIV particles induce upregulation of RANK expression in cells of the monocytic lineage, which may be important for periprosthetic osteoclastogenesis.
    Acta Orthopaedica Scandinavica 07/2004; 75(3):295-302.
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    ABSTRACT: We performed a randomized, prospective study on the prophylaxis of heterotopic ossification (HO) after total hip arthroplasty (THR), comparing indomethacin and the selective COX-2 inhibitor meloxicam. From the day after surgery, 272 patients were treated with 7.5 mg meloxicam, 15 mg meloxicam, or 2 x 50 mg indomethacin a day, for 14 days. After 6 months, radiographs of patients treated with 7.5 mg meloxicam showed that HO had occurred in one third. This treatment was therefore stopped after 26 patients have been assigned to this group. According to the intention-to-treat principle, patients given 15 mg meloxicam developed HO in 25% (20% Brooker grade I, 4% grade II and 1% grade III) and those given indomethacin in 10% (7% Brooker grade I, 1% grade II and 2% grade III), a statistically significant difference.
    Acta Orthopaedica Scandinavica 01/2003; 73(6):611-4.
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    ABSTRACT: The precise cellular mechanism of osteolysis in particle disease is still unknown. The aim of the study was to screen for new gene products in macrophages during particle contact. In an established macrophage model THP1-cells (human monocytic cells) were differentiated under the influence of vitamin D3 and GM-CSF into macrophage-like cells (MLC). MLCs were incubated each with different concentrations of polyethylene particles, Lipopolysaccharids (LPS) and controls. Isolated RNA was transcribed into complementary radioactive 32P labeled cDNA. This probe was hybridised on an human cDNA expression array and analysed by autoradiography. To obtain a more reliable method quantifying mRNA, the reverse transcriptase polymerase chain reaction (RT-PCR) was used. The arrays showed an upregulation of the following genes by particles: TNF-Rezeptor 2, IL-1 Receptor Antagonist, Bone Morphogenic Protein 4 and HM 145. This was proven three times using RT-PCR and statistically significant in comparison to the controls. LPS induced the same upregulation except for HM145 whereas particles caused downregulation of this mRNA expression. Our results prove that the model of differentiated THP-1 cells treated with PE particles is a suitable system to analyse differential gene expression patterns, since the induction of the major positive control genes TNF alpha and IL1 beta were detected by this approach. BMP 4 is known as signal protein which mediates ectopic bone formation and can also be interpreted as a contra regulatory gene. HM 145 belongs to the leukocyte chemotactic peptide receptor family. HM 145 seems to be one of the first genes that is enhanced along the septical pathway but less expressed by contact with particles. Analysis of HM 145 expression might help to diagnose septic versus aseptic loosening of prosthesis.
    Biomedizinische Technik 06/2002; 47(5):111-6. · 1.16 Impact Factor