Observation of the development of fracture process zones in concrete under tension

Imperial Users onl

Ein biomolekularer Marker der Osteoarthritis des Kniegelenks

Fragestellung: Die Identifizierung von biomolekularen Markern der Osteoarthritis ist das wesentlichste aktuelle Ziel der internationalen Osteoarthritisforschung. Tiermodelle sind geeignet zur genaueren Charakterisierung der Osteoarthritis, speziell auch um den Nutzen biomolekularer Marker zu testen. Sowohl im Modell der kompletten medialen Meniskektomie wie auch der vorderen Kreuzbanddurchtrennung untersuchten wir das Cartilage Oligomeric Matrix Protein (COMP). Zwar ist die Funktion dieses Moleküls weiterhin unzureichend bekannt, aber es ist aufgrund einer höheren Menge im Knorpel ein potentieller Marker für Serumuntersuchungen, die ein wichtiger Fortschritt in Diagnostik und Therapie der Osteoarthritis sind. Methodik: Als Modell dienten die einseitige komplette mediale Meniskektomie des Kaninchens mittels Arthrotomie bzw. die vordere Kreuzbanddurchtrennung. Jeweils zu den Zeitpunkten 2, 4, 8 und 12 Wochen nach der Operation wurden im jeweiligen Tiermodell je 8 Kaninchen untersucht. Der makroskopische Befund der operierten und nichtoperierten Seite wurde mittels modifizierter Outerbridge-Skala und mittels des Lokalisationsschemas der International Cartilage Repair Society (ICRS) erhoben. Mikroskopisch wurde jeweils der Gelenkknorpel in der Hämatoxylin-Eosin- und der Safranin O-Färbung untersucht. In der Synovialflüssigkeit der Kniegelenke der operierten und kontralateralen Seite wurde COMP mittels Enzymimmunoassay bestimmt. Zudem wurden Serumanalysen mittels Enzymimmunoassay vorgenommen. Die statistische Analyse erfolgte mittels Wilcoxon-Test (SPSS, Chicago, Ill). Die Tierversuche waren von der Ethikommission der Universität und vom Regierungspräsidium genehmigt. Ergebnisse und Schlussfolgerungen: Die operierten Kniegelenke hatten zu allen Zeitpunkten nach kompletter medialer Meniskektomie und nach vorderer Kreuzbanddurchtrennung erhöhte Scorewerte im Vergleich mit der nichtoperierten Seite. Auch histologisch waren erhöhte Scores in beiden Tiermodellen nachweisbar. Bei Vergleich der operierten mit der kontralateralen, nichtoperierten Seite wurde nach der kompletten medialen Meniskektomie 2 Wochen nach der Operation COMP im operierten Kniegelenk signifikant erhöht gemessen. Im vordere Kreuzbanddurchtrennungsmodell war COMP zu allen Zeitpunkten erhöht. Allerdings war COMP im Serum in keinem der beiden Modelle im Verlauf signifikant erhöht. Mit den Untersuchungen wurde gezeigt, dass Cartilage Cartilage Oligomeric Matrix Protein beim Kaninchen sowohl in der Synovialflüssigkeit wie im Serum nachweisbar ist. Diese beiden Tiermodelle sind gut geeignet, Aspekte des Krankheitsprozesses zu imitieren. Die Bestimmung von COMP zur Verlaufsbeurteilung während des osteoarthritischen Prozesses erscheint in mindestens einem der beiden Kaninchenmodelle geeignet. Die speziell auch beim Einsatz am Menschen vorzuziehende Form der Bestimmung im Serum gab allerdings keine Werte, die für die Verlaufsbeurteilung hilfreich sind. Die Ergebnisse haben eine klare Relevanz für die Erforschung beim Menschen

A tailored approach for the treatment of indirect inguinal hernia in adults—an old problem revisited

Purpose: A patent processus vaginalis peritonei (PPV) presents typically as an indirect hernia with an intact inguinal canal floor during childhood. Little is known however about PPV in adults and its best treatment. Methods: A cohort study included all consecutive patients admitted for ambulatory open hernia repair. In patients with a PPV, demographics, hernia characteristics, and outcome were prospectively assessed. Annulorrhaphy was the treatment of choice in patients with an internal inguinal ring diameter of <30mm. Results: Between 1998 and 2006, 92 PPVs (two bilateral) were diagnosed in 676 open hernia repairs (incidence of 14%). Eighty nine of the 90 patients were males, the median age was 34years (range: 17-85). A PPV was right-sided in 67% and partially obliterated in 66%. Forty-one patients had an annulorrhaphy and 51 patients had a tension-free mesh repair. The median operation time was significantly shorter in the annulorrhaphy group (38 vs. 48min, P<.0001). In a median follow-up period of 56months (27-128), both groups did not differ concerning recurrence (1/41 vs. 2/51), chronic pain (3/41 vs. 4/51), and hypoesthesia (5/41 vs. 9/51). There was however a clear trend to less neuropathic symptoms in favor of annulorrhaphy (0/41 vs. 5/51, P < 0.066). Conclusions: PPV occurs in 14% of adults undergoing hernia repair. In selected patients, annulorrhaphy takes less time and is associated with equally low recurrence but less potential for neuropathic symptom

La réparation sphinctérienne directe: points techniques, indications et résultats

L'incontinence anale est un handicap physique, psychique et social majeur qui a de nombreuses causes différentes. Les méthodes actuellement disponibles pour améliorer les symptômes de cette incontinence sont les méthodes médicales et de rééducation d'une part et les méthodes chirurgicales d'autre part. Quatre techniques chirurgicales répondent à ces objectifs pour la plupart des malades: la sphinctérorraphie, la neuromodulation des racines sacrées, et les deux techniques de substitution que sont le sphincter artificiel et la graciloplastie dynamisée. La réparation sphinctérienne directe est la technique la plus utilisée dans le traitement chirurgical de l'incontinence anale (IA) par lésion sphinctérienne. Cette technique est envisageable chez les malades ayant une incontinence fécale en rapport avec des lésions limitées du sphincter anal externe. La technique chirurgicale est simple (myorraphie par suture directe ou en paletot) et bien codifiée. Les résultats fonctionnels sont imparfaits et se dégradent avec la durée du suivi. Une continence parfaite après réparation sphinctérienne est rarement acquise de façon durable: le malade candidat à cette approche thérapeutique doit en être averti.Pan African Medical Journal 2013; 14:1

Increase in degraded collagen type II in synovial fluid early in the rabbit meniscectomy model of osteoarthritis

SummaryObjectiveThe objective of this study was to determine whether collagen type II breakdown products in synovial fluid (SF), detected by an enzyme-linked immunoassay, represent a useful marker for early events in osteoarthritis (OA) in the rabbit medial meniscectomy model.DesignComplete medial meniscectomy was performed on the right knee joints of 32 rabbits. Balanced groups of rabbits were then sacrificed at 2, 4, 8, and 12 weeks post-surgery. An additional 8 unoperated and 11 sham-operated animals served as controls. SF lavages were performed on right and left knee joints of the same animals at sacrifice. The proteolytic epitope of type II collagen was monitored using an enzyme-linked immunoassay.ResultsMacroscopically visible surface fibrillation and focal erosions appeared as early as 2 weeks after meniscectomy in the femorotibial joint (P<0.01). OA developed gradually during the later observation period, and then predominantly on the medial tibial plateau and medial femur. Significant histological alterations in cartilage, including a loss of proteoglycans, surface irregularities, and clefts, were detected at 2 weeks after meniscectomy (P<0.01). Collagen type II epitope levels in SF lavage samples were elevated peaking at 2 weeks after meniscectomy (P<0.02). Levels decreased at later time points, but they were still raised at 12 weeks (P≤0.05). Highly significant correlations were found between the SF collagen type II epitope levels and the macroscopic and microscopic scoring results (Spearman rho correlation coefficient, macroscopy—collagen type II epitope r=0.222, P=0.025; microscopy—collagen type II epitope r=0.436, P≤0.01).ConclusionIn this rabbit model of medial meniscectomy, levels of type II collagen fragments in SF appear to provide a useful marker of the early degenerative changes

Coronary graft patency after perioperative myocardial infarction: a study with multislice computed tomography‏

A total of 55 consecutive patients who experienced perioperative myocardial infarction (MI) after coronary artery bypass grafting were studied using multislice computed tomography (MSCT) angiography to evaluate for graft patency. The MSCT detected acute graft occlusion in 23% grafts. Of the 55 patients, 40% patients had occluded grafts and perioperative MI in the area of the grafted vessels; remaining 60% had patent grafts with infarction in the area of the grafted vessels. Compared with the patients with patent grafts, those with occluded grafts had a higher blood sugar level. In addition, graft occlusion was higher in grafts with severe distal disease. Among the patients with patent grafts, luminal stenosis of the native vessels supplying the infarcted myocardium was higher than that in the native vessels supplying the non-infarcted myocardium. In conclusion, MSCT is feasible for the assessment of graft patency in the setting of perioperative MI. Graft occlusion is detected in less than half of the cases and usually occurs in the grafts with severe distal involvement and the patients with uncontrolled hyperglycemia. In patients with patent grafts, the severity of luminal stenosis of the native grafted vessel is the main predisposing factor for perioperative MI

Enchondromas and atypical cartilaginous tumors at the proximal humerus treated with intralesional resection and bone cement filling with or without osteosynthesis: retrospective analysis of 42 cases with 6 years mean follow-up

Background: Enchondromas and atypical cartilaginous tumors (ACT) are often located at the proximal humerus. Most lesions can be followed conservatively, but surgical resection may alleviate pain, avoid pathological fractures, and prevent transformation into higher grade chondrosarcomas. Rigorous intralesional resection and filling with polymethylmethacrylate bone cement has been proposed for enchondromas but also for ACT, as an alternative for extralesional resection. We intended to analyze radiological, clinical, and functional outcome of this strategy and compare bone cement without osteosynthesis to bone cement compound osteosynthesis, which has not been analyzed so far. Methods: We retrospectively analyzed 42 consecutive patients (mean follow-up 73 months; range 8–224) after curettage and bone cement filling with or without osteosynthesis. Exclusion criteria were Ollier’s disease and cancellous bone filling. Twenty-five patients only received bone cement. Seventeen patients received additional proximal humerus plate for compound osteosynthesis to increase stability after curettage. Demographics and radiological and clinical outcome were analyzed including surgery time, blood loss, hospitalization, recurrences, and complications. An additional telephone interview at the final follow-up assessed postoperative satisfaction, pain, and function in the quick disabilities of the arm, shoulder, and hand (DASH) score and the Musculoskeletal Tumor Society (MSTS) score. Statistics included the Student T tests, Mann-Whitney U tests, and chi-square tests. Results: No osteosynthesis compared to compound osteosynthesis showed smaller tumors (4.2 (± 1.5) cm versus 6.6 (± 3.0) cm; p = 0.005) and smaller bone cement fillings after curettage (5.7 (± 2.1) cm versus 9.6 (± 3.2) cm; p = 0.0001). A score evaluating preoperative scalloping and soft-tissue extension did not significantly differ (1.9 (± 0.9) versus 2.0 (± 1.0); rating scale 0–4; p = 0.7). Both groups showed high satisfaction (9.2 (± 1.5) versus 9.2 (± 0.9); p = 0.5) and low pain (1.0(±1.7) versus 1.9(±1.8); p = 0.1) in a rating scale from 0 to 10. Clinical and functional outcome was excellent for both groups in the DASH score (6.0 (± 11.8) versus 11.0 (± 13.2); rating scale 0–100; p = 0.2) and the MSTS score (29.0 (± 1.7) versus 28.7 (± 1.1); rating scale 0–30; p = 0.3). One enchondroma recurrence was found in the group without osteosynthesis. Complications (one fracture and one intra-articular screw) were only detected after osteosynthesis. Osteosynthesis had longer surgery time (70 (± 21) min versus 127 (± 22) min; p &lt; 0.0001), more blood loss (220 (± 130) ml versus 460 (± 210) ml; p &lt; 0.0001), and longer stay in the hospital (6 (± 2) days versus 8 (± 2) days; p = 0.004). Conclusions: Intralesional tumor resection was oncologically safe and clinically successful with or without osteosynthesis. Osteosynthesis did not reduce the risk for fracture but was more invasive

Test de l’Effet de la Fiscalité Foncière sur l’Investissement Touristique

The purpose of this paper is to test if there exists an eviction of the private tourism investment by the level of land tax (patent tax and urban tax), linked to investment. The consideration of land tax variable and that of public infrastructure expenditure in the private investment equation allows to model and next to test the effect of fiscal system on the private investment. The anticipated demand seems to have an accelerator effects on tourism investment. In revenge, the land tax based on the level of tourism GDP remains with a negative effect, but it is neatly lower as than the effect, which the land tax would have when this tax is based on the investment level. This fiscal strategy could help to generate income for the human factor operating in the tourism sector