A novel collagenase from Vibrio Alginolyticus: experimental study for Dupuytren's disease.

OBJECTIVE: Dupuytren contracture (DC) is a highly prevalent hand affection in which contracted fingers compromise hand function. It is a benign fibroproliferative condition affecting the hand palmar fascia with a deposition of excess matrix proteins in the extracellular space of the palmar aponeurosis. In particular type III over type I collagen V. Alginolyticus collagenase (CVA), is a new enzyme that is fully active on the collagen filaments and inactive on other components of the dermal extracellular matrix. The aim of this study is to evaluate the safety and effectiveness of an intra-lesional injection of CVA on an animal model of subcutaneous fibrosis mimicking the pathological anatomy of the cord of Dupuytren's disease. MATERIALS AND METHODS: We performed an in vivo study on 27 rats that were randomized into four groups, and we evaluated macroscopic and microscopic analysis examining the inflamed cell population and the extracellular matrix. RESULTS: In all cases, no skin necrosis, skin tears or wound dehiscence were recorded, demonstrating the safety of the CVA in contrast to group D which had full-thickness skin necrosis, and this is confirmed by the microscopic analysis of the samples treated with CVA, where no hematomas are found around the fibrotic area with the absence of leukocyte infiltrates and macrophages. CONCLUSIONS: CVA is confirmed to be selective for collagens I and III, reducing the risk of vascular lesions or skin ulcerations.

Septic arthritis in children.

Osteoarticular infections are a form of diagnostic and therapeutic emergency in infants and children, even if relatively rare. Despite decades of experience with different protocols, and multiple clinical trials, today it is still difficult to determine what kind of antibiotics is really effective, what kind of associations are required, which is the optimal time range of a treatment, when and on which subjects to base the transition from a parenteral treatment to an oral one. Current philosophy aims more and more at reducing hospitalization and costs, and wants to decrease the discomfort in the family. The purpose of these guidelines is to promote a reasoned clinical and therapeutic approach, in a context of diagnostic probabilities that offer the best chance of success in reducing hospitalization with a rapid transition to an oral treatment, and then outpatient, and thus educing totally the processing time.

Osteochondritis dissecans: a multicenter study of the European Pediatric Orthopedic Society.

To assess of the value of conservative and operative treatment of osteochondritis dissecans of the knee, a multicenter study was performed. In 12 European countries, 798 cases of osteochondritis of the knee have been collected from 44 hospitals. Results were based on 452 patients with 509 affected knees with minimum follow-up was 1 year (mean follow-up, 3 years and 11 months) and sufficient data for evaluation: 61% were male patients; 39% female patients; 318 affected knees were found in juvenile patients; 191 affected knees were in adult or premature patients. The localization was the medial femoral condyle on the lateral side in 51% (typical site) of patients. Various other sites were involved. Of the 509 affected knees, 154 were treated conservatively, 355 were treated surgically (many with multiple operations). For evaluation, the initial situation (at the time of the diagnosis) was favorable in 198 patients (no effusion, diameter of the lesion < 20 mm and no gross dissection on imaging) and unfavorable (one of the parameters did not meet these prerequisites) in 311 patients. The results were better in young patients than in adult patients. However, in the adolescent group, 22% of patients had abnormal knee at follow-up. The classical localization has a better prognosis than an unusual one. Patients with a favorable situation at diagnosis have significantly better results after conservative treatment than those who have undergone operation. When there are signs of dissection, the results are better after operative than after conservative treatment.

Behaviour of human osteoblasts cultured on bioactive glass coatings.

Two new formulations of bioactive glasses were used as coatings on titanium alloy (TiAl6V4) implants for prosthetic applications in the orthopaedic field. The biocompatibility of these bioglasses, as well as their osteoconductive properties, were assessed by employing primary cultures of human osteoblasts. A nonbioactive glass, the titanium alloy and polystyrene surface were used as controls. The results obtained demonstrated that the two bioglasses elicited a rapid and strong proliferative response by osteoblasts, which spread, formed a close layer and then expressed the specific osteoblastic marker i.e. osteocalcin. In comparison, cells grew on the nonbioactive glass to a much minor extent, similar to that of polystyrene control, showing individual cellular elements not forming a compact sheet, but expressed levels of osteocalcin clearly higher than both the polystyrene control and the two bioglasses. Finally, a very low proliferative rate of osteoblasts and the synthesis of hardly detectable osteocalcin amounts were observed with the titanium alloy. In conclusion, our studies indicate that the new bioactive glasses are effective in stimulating osteoblast growth and differentiation.

Biocompatibility studies on glass ionomer cements by primary cultures of human osteoblasts.

Glass ionomer cements (GICs) are materials largely employed in the dental field that have been considered recently as cements in orthopaedic surgery for their proven osteogenic features. The aim of this study was to compare the response of cultured human osteoblastic cells to a number of commercial glass ionomer cements in order to provide indications useful for the further development of formulations that have potential for use as cements or implants in repair and replacement of bone tissue. The GICs tested were: Ketac-Fil Aplicap, lonocem lonocap 1,0, GC Fuji II, GC Fuji II LC and Vitremer 3M. Several features such as plating efficiency, adhesion and morphology of the cells were studied, as well as the only specific biochemical parameter of osteoblastic phenotype, namely osteocalcin production. In addition, the colonisation of materials by osteoblastic cells was verified by means of scanning electron microscopy. Altogether, the results obtained indicate that four of the five glass ionomer cements tested are biocompatible, showing vital cells adhering to the materials, proliferating and expressing the biochemical markers of osteoblastic phenotype, whereas Vitremer 3M, although currently employed in the dental field, exhibits a great cytotoxicity toward the cells. The adverse reaction of this GIC can be attributed to the leaching of at least two components of the polyacidic phase evidenced by protonic magnetic resonance analysis (PMR), namely 2-hydroxyethylmethacrylate (HEMA), and an unidentified acidic species. The addition of pure HEMA at the same concentrations found by means of PMR to cultures of osteoblastic cells resulted in a complete cell death. Our results also show that in vitro methods employing primary cultures of human cells specific to the implant sites of prostheses are appropriate and suitable tools for evaluating biocompatibility of materials. Furthermore, this kind of approach can provide indications useful in the design of novel materials as well as in improving the characteristics of the formulations already available.

Cultures of human embryonic osteoblasts. A new in vitro model for biocompatibility studies.

Cell populations derived from human embryonic bone were isolated according to the ability of osteoblasts to migrate from bone onto glass fragments. Morphologic and biochemical assays showed (1) osteoblast-like appearance; (2) elevated alkaline phosphatase 1,25(OH)2D3 responsive activity associated with plasma membranes and matrix vesicles; (3) production of a thick extracellular matrix, mainly composed of Type I collagen, which mineralized in the presence of 10 mM beta-glycerophosphate; and (4) higher growth rate and viability when compared with their mature counterpart. Cultures of embryonic cells were challenged with particles of several biomaterials, and their effects on morphology, vitality, and osteogenic capacity of the cultured cells were tested. Stainless steel, titanium alloy, Co-Cr-Mo alloy (vitallium), carbon fiber-reinforced polybutylene terephtalate, ultra-high molecular weight polyethylene, ceramic, calcium phosphate, and hydroxyapatite did not exert any significant deleterious effects on the cultured human osteoblasts.

[Neonatal screening for congenital hip dislocation. Indication of ultrasonography from a systematic study correlating clinical findings and ultrasonography]. / Le dépistage néonatal de la luxation congénitale de hanche (L.C.H.). Indications de l'échographie à partir d'une étude systématique corrélant clinique et échographie.

INTRODUCTION: The aim of our study was to verify the correlation between clinical and sonographic screening for CDH. MATERIALS AND METHODS: Clinical and sonographic screening was carried out in 1000 newborns (2000 hips) during the first week of life. Anamnestic risk factors were evaluated and clinical examination was performed using the BARLOW, Le DAMANY and ORTOLANI maneuvers. We also took into account a possible limitation of abduction due to adductor hypertonia and the presence of a hip crepitation. All hips were evaluated by ultrasound examination using Graf's morphologic method. We considered as clinically pathological the positive BARLOW, Le DAMANY and ORTOLANI hips and "doubtful" the stable hips having "crepitation" or "hypertonia of the adductors". The hips considered pathological with the ultrasound were the hips 2c, 3a and 3b according to GRAF. RESULTS: 1) Hips clinically pathological (BARLOW, Le DAMANY and ORTOLANI): 150 (7.5 per cent). 2) The clinically stable hips but "doubtful":--crepitation: 105 (5.25 per cent); adductor hypertonia: 86 (4.3 per cent), total 191 (9.55 per cent). 3) Hips clinically normal but with at least anamnestic risk factor: 198 (9.9 per cent); 4) Hips clinically normal but without anamnestic risk factor: 1461 (73.05 per cent). 5) Hips echographically pathological, that is 2c, 3a and 3b according to Graf: 124 (6.2%) and particularly 2c: 61 (3.05 per cent), 3a: 61 (3.05 per cent) and 3b: 2 (0.1 per cent). DISCUSSION: 1) In the clinically pathological hips (BARLOW positive) 36 were echographically pathological with a clinical-sonographic correlation of 28.3 per cent (36 out of 127); all the ORTOLANI positive hips, were echographically pathological (100 per cent (23 out of 23)). In doubtful hips, sonograms were pathological in 17 of 105 hips with "crepitation" (0.85 per cent) and in 13 of 86 hips with "adductor hypertonia" (0.65 per cent). 2) The clinically and echographically pathological hips at birth, that is 2c, 3a and 3b, must be followed for months. At follow up they showed in almost all the cases an evolution towards normality. It is, therefore, indicated to repeat the clinical and sonographic examination in the first month, before undertaking any kind of treatment. 3) Finally, 12 hips, 0.6 per cent, presenting pathological sonographic type 2c and 3a, were found clinically normal. Nevertheless, almost all of these hips evolved normally. From this study only 0.05 per cent of clinically normal hips presented, later, a dysplasia of the acetabulum. Analysis of the results clearly showed that ultrasound examination may be an excellent help to clinical examination which, if well performed, has top priority for early diagnosis of C.D.H. CONCLUSION: The clinical examination, carefully performed in the first days of life, has priority because it allows discovering a pathological hip or a hip at risk. The sonographic examination is a useful image complementing the clinical examination because it allows confirmation of the diagnosis and follow up of the morphologic evolution of the hip with an inoffensive method and it can give indications for possible treatment. From our study we may conclude that at birth a clinical screening is preferable and that the ultrasound study is to be reserved for pathological, doubtful or at risk hips.

Herniated disk in adolescents.

Twenty-one patients (9 female and 12 male) aged from 13 to 22 years were observed for lumbago and lumbo-sciatica caused by a discopathy which was subsequently confirmed by radiology and surgery. None of these patients had a history of trauma. It must be underlined that the painful symptoms exhibited and the young age of the patients suggest such pathologies as infections, tumours or malformations, but the possibility of discopathy must always be considered. It is also interesting to note the differences observed in symptomatology between adults and adolescents and to consider the various pathogenetic factors which might cause discopathy in adolescents while it was until now believed to be reserved to adults.

Isolation and characterization of human embryonic osteoblasts.

Human osteoblasts were obtained by migration and proliferation of cells from embryonic membranous bone on glass fragments. Light and electron microscopy analyses revealed a typical osteoblast-like appearance with high protein synthesis activity. The cells showed high alkaline phosphatase activity that was associated with plasma membranes and matrix vesicles and was 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] responsive. In contrast to the adult osteoblasts, embryonic cells could not produce detectable levels of osteocalcin, not even in the presence of 1,25(OH)2D3. Osteoblasts grown in multilayers produced a thick extracellular matrix, mainly composed of type I collagen, that mineralized in the presence of 10 mM beta-glycerophosphate. Because of their intrinsic osteogenic capacity, embryonic osteoblasts represent a valuable model for studying the mineralization process in vitro. In addition, the embryonic origin of these cells renders them a precious experimental system for the elucidation of mechanisms at the basis of differentiation of osteoblastic lineage.