MTM1-mediated production of phosphatidylinositol 5-phosphate fuels the formation of podosome-like protrusions regulating myoblast fusion.

Myogenesis is a multistep process that requires a spatiotemporal regulation of cell events resulting finally in myoblast fusion into multinucleated myotubes. Most major insights into the mechanisms underlying fusion seem to be conserved from insects to mammals and include the formation of podosome-like protrusions (PLPs) that exert a driving force toward the founder cell. However, the machinery that governs this process remains poorly understood.

Lysosome identity crisis: Phosphoinositides and mTORC1 negotiate lysosomal behavior.

Ebner et al. discovered a nutrient-dependent molecular feedback circuit that employs mTORC1, lipid kinases, and phosphatases to generate phosphatidylinositol-3-phosphate [PI(3)P] or phosphatidylinositol-4-phosphate [PI(4)P] in a mutually exclusive manner on lysosomes, which respectively convert lysosomes into organelles that support anabolism or catabolism.

Quantitative Immunofluorescence to Study Phagosome Maturation and Resolution.

Cells such as macrophages and neutrophils can internalize a diverse set of particulate matter, illustrated by bacteria and apoptotic bodies through the process of phagocytosis. These particles are sequestered into phagosomes, which then fuse with early and late endosomes and ultimately with lysosomes to mature into phagolysosomes, through a process known as phagosome maturation. Ultimately, after particle degradation, phagosomes then fragment to reform lysosomes through phagosome resolution.

X-linked myotubular myopathy is associated with epigenetic alterations and is ameliorated by HDAC inhibition.

X-linked myotubular myopathy (XLMTM) is a fatal neuromuscular disorder caused by loss of function mutations in MTM1. At present, there are no directed therapies for XLMTM, and incomplete understanding of disease pathomechanisms. To address these knowledge gaps, we performed a drug screen in mtm1 mutant zebrafish and identified four positive hits, including valproic acid, which functions as a potent suppressor of the mtm1 zebrafish phenotype via HDAC inhibition.

Liposome-Based Methods to Study Protein-Phosphoinositide Interaction.

Following their generation by lipid kinases and phosphatases, phosphoinositides regulate important biological processes such as cytoskeleton rearrangement, membrane remodeling/trafficking, and gene expression through the interaction of their phosphorylated inositol head group with a variety of protein domains such as PH, PX, and FYVE. Therefore, it is important to determine the specificity of phosphoinositides toward effector proteins to understand their impact on cellular physiology. Several methods have been developed to identify and characterize phosphoinositide effectors, and liposomes-based methods are preferred because the phosphoinositides are incorporated in a membrane, the composition of which can mimic cellular membranes.

Radioscapholunate arthrodesis versus radiolunate arthrodesis in rheumatoid wrist surgery: Clinical and radiographic outcomes.

Radiolunate arthrodesis is a validated surgical technique in rheumatoid wrist surgery. When the radioscaphoid joint is involved or when there is radiolunate instability, a radioscapholunate arthrodesis must be preferred. The objective was to compare clinical and radiographic outcomes for both types of arthrodesis.

Protein-Lipid Interaction by Fluorescence (PLIF) to Characterize and Screen for Inhibitors of Protein-Phosphoinositide Interactions.

Phosphoinositides are key signaling and regulatory phospholipids that mediate important pathophysiological processes. This is achieved through the interaction of their phosphorylated inositol head group with a wide range of protein domains. Therefore, being able to determine the phosphoinositide specificity for effector protein is essential to the understanding of its cellular function.

Experience with the Coonrad-Morrey total elbow arthroplasty: 78 consecutive total elbow arthroplasties reviewed with an average 5 years of follow-up.

Background: The Coonrad-Morrey total elbow arthroplasty is a linked implant. This study investigated the hypotheses that reliable results can be obtained in rheumatoid patients and in traumatic conditions and that the survival rate is similar to or better than what has been published for nonlinked implants.

Methods: Surgery was performed on 70 consecutive patients (78 elbows) for an inflammatory arthritis (45 elbows) or a traumatic condition (33 elbows: 18 acute fractures of the distal humerus, 10 nonunions, and 5 post-traumatic arthritis).

Results with a minimum of 10 years follow-up of the Coonrad/Morrey total elbow arthroplasty.

Introduction: Few series have evaluated the long-term results of total elbow arthroplasty (TEA).

Materials And Methods: Fifteen patients with a Coonrad/Morrey total elbow implant were reviewed with a minimum follow-up of 10 years. There were nine women and six men with a mean age of 55 years at surgery.

Outcomes of two surgical revision techniques for recurrent anterior shoulder instability following selective capsular repair.

Introduction: Conventional capsulolabral reconstruction for anterior shoulder instability fails with recurrent instability in up to 23% of cases. Few studies have evaluated surgical revision strategies and outcomes. The objective of this study was to evaluate clinical and radiographic outcomes in a homogeneous series of surgical revisions after selective capsular repair (SCR).

Hemiarthroplasty for osteoarthritis in shoulder with dysplastic morphology.

Hypothesis: Hemiarthroplasty for shoulder osteoarthritis with a glenoid dysplasia gives satisfactory results at medium-range follow-up.

Materials And Methods: From 1998 to 2006, 9 patients (10 shoulders) with glenoid dysplasia and osteoarthritis were treated with shoulder hemiarthroplasty. The mean age at surgery was 54 years (range, 44-73 years).

Long-term outcome of distal ulna resection-stabilisation procedures in post-traumatic radio-ulnar joint disorders.

Introduction: Distal radius fractures represent 20% of fractures in adults. Although good results are usually obtained with treatment, functional sequelae are not uncommon, with injury of the distal radio-ulnar joint (DRUJ) being the most frequent. Various treatments have been described to address these disorders.

[Total trapeziectomy with suspension and interposition tendinoplasty for trapeziometacarpal osteoarthrisis: results at 6.5 years average follow-up].

Objectives: Total trapeziectomy remains the main surgical treatment of trapeziometacarpal osteoarthritis. Little has been reported on the long-term results of this technique. We report in this study our experience with our technique of trapeziectomy associated with interposition and suspension tendinoplasty using the abductor pollicis longus tendon with 78 months average follow-up.

[Traumatic avulsion of the flexor digitorum profundus tendon. Report of 20 cases].

Traumatic avulsion of the flexor digitorum profundus tendon or "jersey" finger is uncommon. Twenty patients have been reviewed at an average follow-up of seven years. Patients were seen less than three weeks from trauma in two-thirds of the cases, whereas in one third it was later.

Selective capsular repair for the treatment of anterior-inferior shoulder instability: review of seventy-nine shoulders with seven years' average follow-up.

Hypothesis: Selective capsular repair for the treatment of antero-inferior shoulder instability gives satisfactory results at mid-range follow-up.

Materials And Methods: Seventy-five patients (79 shoulders) with anterior instability underwent selective tightening of the anterior capsule and repair of any labral lesion.

Results: At an average of seven years (5-12 years), results according to the Duplay-Walch score and Rowe score were satisfactory in 80% and 92% of the cases, respectively.

[Surgical treatment of anterior shoulder instability in rugby players: clinical and radiographic results with minimum five-year follow-up].

Purpose Of The Study: In rugby players, 9 to 11% of injuries involve shoulder trauma. Anterior dislocation is one of the most severe accidents affecting the upper limb; recurrent dislocation, observed in more than 60%, appears to be related to the characteristic mechanism of injury in this sport (tackling). Surgical treatment for this instability is a bone block or capsulolabral repair.

Age- and gender-related distribution of bone tissue of osteoporotic humeral head using computed tomography.

Treatment of proximal humeral fractures is very challenging in elderly patients with osteoporosis. Difficulty in obtaining a stable osteosynthesis remains the main problem for the surgeon. Knowing more details about the bone quality of the humeral head can be helpful for treatment.

[Partial trapezectomy with suspension and interposition tendinoplasty for trapezometacarpal osteoarthritis: 5 years results].

Objectives: Partial trapezectomy with suspension and interposition tendinoplasty is an alternative to total trapezectomy or trapezometacarpal arthroplasty for the treatment of trapezometacarpal osteoarthritis. This technique preserves the thumb length allowing good motion and satisfactory pollicidigital strength. The purpose of the present study is to report our experience with this procedure reviewing a continuous monocentric series of 41 thumbs with an averaged follow-up of 5 years.

Evaluation of the glenoid implant survival using a biomechanical finite element analysis: influence of the implant design, bone properties, and loading location.

Total shoulder arthroplasty has become a successful surgical procedure through design improvements. However, lucent lines around the glenoid component are of major concern for leading to component loosening. To better understand the mechanism causing loosening, a finite element biomechanical model of an in vivo scapula was developed.

[Traumatic knee dislocation with popliteal vascular disruption: retrospective study of 14 cases].

Purpose Of The Study: Complex femorotibial dislocation of the knee joint generally results from high-energy trauma caused by a traffic or a contact sport accident. Besides disruption of the cruciate ligaments, in 10-25% of patients present concomitant palsy of the common peroneal nerve and more rarely disruption of the popliteal artery. The purpose of this work was to assess outcome in a monocentric consecutive series of knee dislocations with ischemia due to disruption of the popliteal artery and to focus on specific aspects of management.

[Single-plane external fixation of fresh fractures of the femur: critical analysis of 53 cases].

Purpose Of The Study: External fixation has not been widely used for femoral fractures and few series are reported in the literature. External fixation is generally reserved for severe open fractures, for vessel injury or multiple trauma with life threatening. We present a retrospective analysis of a serie treated in a single center in order to detail the indications of this fixation technique.

A comparative study of endothelial cell markers expressed in chronically inflamed human tissues: MECA-79, Duffy antigen receptor for chemokines, von Willebrand factor, CD31, CD34, CD105 and CD146.

Endothelial cells play a central role in chronic inflammation: for example, they express adhesion molecules and present chemokines leading to enhanced leukocyte recruitment into tissues. Numerous markers of endothelial cells have been reported but there has been a lack of comparative data on their specificity. The present study compared the specificity of seven endothelial cell markers in the rheumatoid synovium and the colon of patients with Crohn's disease.

Shoulder arthroplasty for atraumatic avascular necrosis of the humeral head: nineteen shoulders followed up for a mean of seven years.

Nineteen shoulder arthroplasties for the treatment of nontraumatic avascular necrosis of the humeral head were evaluated. The osteonecrosis was idiopathic in 6 shoulders, was a result of corticotherapy in 10, occurred after radiation in 2, and occurred after Gaucher's disease in 1. A total shoulder arthroplasty was performed in 5 cases and a hemiarthroplasty in 14.