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Oliver Tannous MD Alec C. Stall MD Cullen Griffith MD Christopher T. Donaldson MD Rudolph J. Castellani Jr MD Vincent D. Pellegrini Jr MD 《Clinical orthopaedics and related research》2013,471(5):1584-1592
Background
Heterotopic ossification (HO) occurs most commonly after trauma and surgery about the hip and may compromise subsequent function. Currently available animal models describing the cellular progression of HO are based on exogenous osteogenic induction agents and may not reflect the processes following trauma.Questions/purposes
We therefore sought to characterize the histologic progression of heterotopic bone formation in an animal model that recapitulates the human condition without the addition of exogenous osteogenic material.Methods
We used a rabbit model that included intramedullary instrumentation of the upper femur and ischemic crush injury of the gluteal muscle. Bilateral surgical induction procedures were performed on 30 animals with the intention of inciting the process of HO; no supplemental osteogenic stimulants were used. Three animals were sacrificed at each of 10 predetermined times between 1 day and 26 weeks postoperatively and the progression of tissue maturation was graded histologically using a five-item scale.Results
Heterotopic bone reliably formed de novo and consistently followed a pathway of endochondral ossification. Chondroid elements were found in juxtaposition with immature woven bone in all sections that contained mature osseous elements.Conclusions
These results establish that HO occurs in an animal model mimicking the human condition following surgical trauma about the hip; it is predictable in its histologic progression and follows a pathway of endochondral bone formation.Clinical Relevance
By showing a consistent pathway of endochondral ossification leading to ectopic bone formation, this study provides a basis for understanding the mechanisms by which HO might be mitigated by interventions. 相似文献64.
Cucchetti A Cescon M Trevisani F Morelli MC Ercolani G Pellegrini S Erroi V Bigonzi E Pinna AD 《Digestive and liver disease》2012,44(6):523-529
BackgroundThe strategy of salvage transplantation for patients with hepatocellular carcinoma is based on the premise that tumour recurrence will be still transplantable at the time of recurrence. However, patients can not only present non-transplantable recurrence but can also be over the age limit accepted for transplantation.AimsTo measure the risk of being too old for salvage transplantation of patients resected for hepatocellular carcinoma within Milan criteria.MethodsA Markov simulation model was developed on the basis of published literature.ResultsThe risk of being too old for salvage transplantation depends on the time-span between age at hepatic resection and age limit, and the expected median waiting-time. Patients resected at an age 2 or 3 years below the age limit carry a risk of being too old that overcomes the probability of receiving transplantation. Salvage strategy can cause harm that depends on the tumour characteristics and degree of portal hypertension, becoming maximal for patients with multiple tumours, clinical signs of portal hypertension and increased bilirubin levels.ConclusionsThe best strategy to adopt should be balanced between the risk of being too old and the expected transplant benefit, but salvage strategy could be pursued if it did not turn into significant harm in comparison to primary transplantation. 相似文献
65.
Michele Arcangelo Verdano Andrea Pellegrini Paolo Schiavi Luca Somenzi Giorgio Concari Francesco Ceccarelli 《International orthopaedics》2013,37(10):2001-2007
Purpose
The purpose of this study was to investigate the clinical and sonographic impact on the rotator cuff (RC) of the use of the anterolateral approach for nailing.Methods
A retrospective cohort of 48 patients treated for humeral diaphyseal fractures at the University Hospital of Parma between 2007 and 2011 was analysed. Inclusion criteria were (1) acute humeral shaft fractures treated with T2-proximal humeral nail (PHN) and (2) a minimum follow-up of one year. Exclusion criteria were (1) history of proximal and metaphyseal humeral fractures, (2) pathological fractures or open fractures of the humerus, and (3) RC lesions. Clinical assessment using the Constant score, simple shoulder test and through shoulder examination tests was carried out. The sonographic study investigated the integrity of the RC.Results
Mean score on Constant’s scale was 78.21 points, with most patients achieving a good result (79 % obtained more than 65 points). One patient had a limited functional outcome (Constant’s score of 49 points). The sonographic findings described for supraspinatus tendon were a partial ruptures of less than 30 mm in three patients and a complete tendon rupture in one case.Conclusions
The results of this study suggest that the use of the anterolateral approach for antegrade humeral nailing ensures a good functional result with no significant clinical-sonographic impact on the rotator cuff and a satisfactory long term clinical outcome. 相似文献66.
D. Paolicelli M. D’Onghia F. Pellegrini V. Direnzo P. Iaffaldano V. Lavolpe M. Trojano 《Journal of neurology》2013,260(6):1562-1568
The impact of neutralizing antibodies (NAbs) on interferon β (IFNβ) efficacy in MS patients is still an object of controversy. To evaluate the clinical response to IFNβ during NAb-positive (NAb+) and NAb-negative (NAb?) statuses on a large population of relapsing remitting (RR) MS patients were followed up to 5 years. Sera from 567 RR MS patients treated with IFNβ for 2–5 years were collected every 6–12 months and evaluated for NAb presence by a cytopathic effect assay. The relapse rate and expanded disability status scale (EDSS) score were assessed at baseline and every 6 months for each patient. A NAb+ status was defined after two consecutive positive titers of NAbs >/= 20 neutralizing units (NU)/mL. Multivariate models were used to analyze the relapse rate, the time to first relapse, the time to confirmed EDSS score 4 during NAb+ and NAb? statuses. A propensity score (PS) matching analysis was performed to assess the robustness of the multivariate models. Fourteen percent of patients became NAb+ during the follow-up. A significant increase of the relapse rate (IRR = 1.38; p = 0.0247) and decrease of the time to 1st relapse (IRR = 1.51; p = 0.0111) were found during NAb+ periods. The PS matching analysis, in a selected cohort of patients, demonstrated a negative trend of NAbs on the time to reach the milestone EDSS 4 (IRR = 2.94; p = 0.0879). This long-term post-marketing observational study further confirms that the occurrence of NAbs significantly affects the risk of disease worsening in IFNβ- treated RRMS. 相似文献
67.
Miryam Carecchio MD Monia Magliozzi BSc Massimiliano Copetti PhD Alessandro Ferraris MD PhD Laura Bernardini PhD Monica Bonetti BSc Giovanni Defazio MD Mark J. Edwards PhD Isabella Torrente BSc Fabio Pellegrini MSc Cristoforo Comi MD PhD Kailash P. Bhatia MD FRCP Enza Maria Valente MD PhD 《Movement disorders》2013,28(6):787-794
Mutations or exon deletions of the epsilon‐sarcoglycan (SGCE) gene cause myoclonus‐dystonia (M‐D), but a subset of M‐D patients are mutation‐negative and the sensitivity and specificity of current genetic testing criteria are unknown. We screened 46 newly enrolled M‐D patients for SGCE mutations and deletions; moreover, 24 subjects previously testing negative for SGCE mutations underwent gene dosage analysis. In our combined cohorts, we calculated sensitivity, specificity, positive and negative predictive values, and area under the curve of 2 published sets of M‐D diagnostic criteria. A stepwise logistic regression was used to assess which patients' characteristics best discriminated mutation carriers and to calculate a new mutation predictive score (“new score”), which we validated in previously published cohorts. Nine of 46 (19.5%) patients of the new cohort carried SCGE mutations, including 5 novel point mutations and 1 whole‐gene deletion; in the old cohort, 1 patient with a complex phenotype carried a 5.9‐Mb deletion encompassing SGCE. Current diagnostic criteria had a poor ability to discriminate SGCE‐positive from SGCE‐negative patients in our cohort; conversely, age of onset, especially if associated with psychiatric features (as included in the new score), showed the best discriminatory power to individuate SGCE mutation carriers, both in our cohort and in the validation cohort. Our results suggest that young age at onset of motor symptoms, especially in association with psychiatric disturbance, are strongly predictive for SGCE positivity. We suggest performing gene dosage analysis by multiple ligation‐dependent probe amplification (MLPA) to individuate large SGCE deletions that can be responsible for complex phenotypes. © 2013 Movement Disorder Society 相似文献
68.
Perilli M Celenza G Fiore M Segatore B Pellegrini C Luzzaro F Rossolini GM Amicosante G 《The Journal of antimicrobial chemotherapy》2007,60(4):877-880
OBJECTIVES: Kinetic characterization of TEM-134, a new TEM-type extended-spectrum beta-lactamase variant isolated from Citrobacter koseri during an Italian nationwide survey. TEM-134 is a natural derivative of TEM-2 with the following substitutions: E104K, R164H and G238S. METHODS: Recombinant TEM-134 was purified from Escherichia coli HB101 (pMGP-134) by three chromatographic steps (cation-exchange chromatography, gel permeation and fast chromatofocusing). Steady-state kinetic parameters (K(m) and k(cat)) were determined by measuring substrate hydrolysis under initial rate conditions using the Hanes linearization of the Michaelis-Menten equation. Modelling was carried out using the software Modeller (version 9.1). RESULTS: TEM-134 hydrolysed with variable efficiency (k(cat)/K(m) ranging from 5 x 10(3) to 8.0 x 10(5) M(-1) . s(-1)) penicillins, narrow-spectrum cephalosporins, cefepime, cefotaxime, ceftazidime and aztreonam, which appeared to be the best substrate. Molecular modelling of the enzyme indicated that the R164H substitution may result in a compromised omega loop in TEM-134 and this may be responsible for its narrower spectrum of activity. CONCLUSIONS: Kinetic data and molecular modelling suggested that R164H has a mild detrimental effect on the global activity of the enzyme. 相似文献
69.
Giacomo Corrado Liliana Mereu Stefano Bogliolo Vito Cela Barbara Gardella Isabella Sperduti Camilla Certelli Alice Pellegrini Giulia Posar Ashanti Zampa Saverio Tateo Angiolo Gadducci Arsenio Spinillo Enrico Vizza 《The international journal of medical robotics + computer assisted surgery : MRCAS》2020,16(2)