Fijación artroscópica sin metal del bloque óseo en la inestabilidad anterior del hombro. Resultados funcionales y radiológicos a corto plazo / Arthroscopic bone block metal-free fixation for anterior shoulder instability. Short-term functional and radiological outcomes

Introducción: Existen múltiples técnicas para la reconstrucción del defecto óseo glenoideo con bloque óseo en la inestabilidad glenohumeral anterior que reducen el riesgo de recidiva tras cirugía de partes blandas, la mayoría utilizando fijación metálica. El objetivo de este estudio es evaluar la seguridad quirúrgica y los resultados funcionales y radiológicos a corto plazo de los pacientes sometidos a una técnica artroscópica con bloque óseo y fijación sin metal. Material y métodos: Estudio retrospectivo de pacientes con inestabilidad y defecto óseo glenoideo>15% con 12 meses de seguimiento mínimo. Se sometieron a estudio radiográfico y tomografía axial computarizada. Se cumplimentaron escalas funcionales de manera pre y postoperatoria: el Western Ontario Shoulder Instability Index y la escala de Rowe. Resultados: Se incluyeron un total de 21 pacientes con una edad media de 30,6 (DE 7,1). Todos mostraron consolidación radiográfica a los 3 meses. El 90,4% de los injertos presentó osteólisis en las áreas más periféricas y el 95,2% presentó consolidación en las áreas de contacto con la glenoides. La media del área de superficie de la glenoides pasó del 79,3% preoperatoria al 98,4% a los 12 meses. Los resultados funcionales medios resultaron estadísticamente significativos (p<0,001) tanto para el Western Ontario Shoulder Instability Index (de 35,6 a 86,9) como para la escala de Rowe (de 25,2 a 96,4). No se presentaron complicaciones graves. Conclusión: La técnica de bloque óseo y fijación sin metal es un método de fijación seguro, sin componentes metálicos. Consigue una consolidación completa del injerto con buenos resultados funcionales y radiográficos a los 12 meses.(AU)

Introduction: Anterior glenohumeral bone loss reconstruction reduces failure rates after soft tissue surgery in patients with large glenoid bone defects. Multiple bone block techniques have been described, most with metal hardware fixation. The objective of this study is to evaluate the safety, as well as the short-term functional and radiological results of an arthroscopic bone block metal-free fixation or bone block cerclage. Material and methods: Retrospective study of patients with glenohumeral instability and>15% glenoid bone loss operated during 2019 with follow-up of at least 12 months. Radiography and computerized tomography studies were performed. Functional outcomes were evaluated before and after surgery with the Western Ontario Shoulder Instability Index and Rowe score. Results: A total of 21 patients with a median age of 30.6 (SD 7.1) were included. All showed radiographic consolidation at 3 months follow-up. A percentage of 90.4 of bone grafts presented osteolysis at peripherical areas and 95.2% revealed consolidation in the areas with contact to the glenoid. The median glenoid estimated surface went from 79.3% before surgery to 98.4% at 12 months. Functional scores were statically significant (P<.001) for Western Ontario Shoulder Instability Index (35.6-86.9) and Rowe score (25.2 to 96.4). No serious complications were reported. Conclusion: The bone block cerclage is a safe, metal-free technique that achieves total consolidation of the bone graft and favorable functional and radiological outcomes at 12 months follow-up.(AU)

Arthroscopic bone block metal-free fixation for anterior shoulder instability. Short-term functional and radiological outcomes / Fijación artroscópica sin metal del bloque óseo en la inestabilidad anterior del hombro. Resultados funcionales y radiológicos a corto plazo

Introduction: Anterior glenohumeral bone loss reconstruction reduces failure rates after soft tissue surgery in patients with large glenoid bone defects. Multiple bone block techniques have been described, most with metal hardware fixation. The objective of this study is to evaluate the safety, as well as the short-term functional and radiological results of an arthroscopic bone block metal-free fixation or bone block cerclage. Material and methods: Retrospective study of patients with glenohumeral instability and>15% glenoid bone loss operated during 2019 with follow-up of at least 12 months. Radiography and computerized tomography studies were performed. Functional outcomes were evaluated before and after surgery with the Western Ontario Shoulder Instability Index and Rowe score. Results: A total of 21 patients with a median age of 30.6 (SD 7.1) were included. All showed radiographic consolidation at 3 months follow-up. A percentage of 90.4 of bone grafts presented osteolysis at peripherical areas and 95.2% revealed consolidation in the areas with contact to the glenoid. The median glenoid estimated surface went from 79.3% before surgery to 98.4% at 12 months. Functional scores were statically significant (P<.001) for Western Ontario Shoulder Instability Index (35.6-86.9) and Rowe score (25.2 to 96.4). No serious complications were reported. Conclusion: The bone block cerclage is a safe, metal-free technique that achieves total consolidation of the bone graft and favorable functional and radiological outcomes at 12 months follow-up.(AU)

Introducción: Existen múltiples técnicas para la reconstrucción del defecto óseo glenoideo con bloque óseo en la inestabilidad glenohumeral anterior que reducen el riesgo de recidiva tras cirugía de partes blandas, la mayoría utilizando fijación metálica. El objetivo de este estudio es evaluar la seguridad quirúrgica y los resultados funcionales y radiológicos a corto plazo de los pacientes sometidos a una técnica artroscópica con bloque óseo y fijación sin metal. Material y métodos: Estudio retrospectivo de pacientes con inestabilidad y defecto óseo glenoideo>15% con 12 meses de seguimiento mínimo. Se sometieron a estudio radiográfico y tomografía axial computarizada. Se cumplimentaron escalas funcionales de manera pre y postoperatoria: el Western Ontario Shoulder Instability Index y la escala de Rowe. Resultados: Se incluyeron un total de 21 pacientes con una edad media de 30,6 (DE 7,1). Todos mostraron consolidación radiográfica a los 3 meses. El 90,4% de los injertos presentó osteólisis en las áreas más periféricas y el 95,2% presentó consolidación en las áreas de contacto con la glenoides. La media del área de superficie de la glenoides pasó del 79,3% preoperatoria al 98,4% a los 12 meses. Los resultados funcionales medios resultaron estadísticamente significativos (p<0,001) tanto para el Western Ontario Shoulder Instability Index (de 35,6 a 86,9) como para la escala de Rowe (de 25,2 a 96,4). No se presentaron complicaciones graves. Conclusión: La técnica de bloque óseo y fijación sin metal es un método de fijación seguro, sin componentes metálicos. Consigue una consolidación completa del injerto con buenos resultados funcionales y radiográficos a los 12 meses.(AU)

Arthroscopic bone block metal-free fixation for anterior shoulder instability. Short-term functional and radiological outcomes. / Fijación artroscópica sin metal del bloque óseo en la inestabilidad anterior del hombro. Resultados funcionales y radiológicos a corto plazo.

INTRODUCTION: Anterior glenohumeral bone loss reconstruction reduces failure rates after soft tissue surgery in patients with large glenoid bone defects. Multiple bone block techniques have been described, most with metal hardware fixation. The objective of this study is to evaluate the safety, as well as the short-term functional and radiological results of an arthroscopic bone block metal-free fixation or bone block cerclage. MATERIAL AND METHODS: Retrospective study of patients with glenohumeral instability and>15% glenoid bone loss operated during 2019 with follow-up of at least 12 months. Radiography and computerized tomography studies were performed. Functional outcomes were evaluated before and after surgery with the Western Ontario Shoulder Instability Index and Rowe score. RESULTS: A total of 21 patients with a median age of 30.6 (SD 7.1) were included. All showed radiographic consolidation at 3 months follow-up. A percentage of 90.4 of bone grafts presented osteolysis at peripherical areas and 95.2% revealed consolidation in the areas with contact to the glenoid. The median glenoid estimated surface went from 79.3% before surgery to 98.4% at 12 months. Functional scores were statically significant (P<.001) for Western Ontario Shoulder Instability Index (35.6-86.9) and Rowe score (25.2 to 96.4). No serious complications were reported. CONCLUSION: The bone block cerclage is a safe, metal-free technique that achieves total consolidation of the bone graft and favorable functional and radiological outcomes at 12 months follow-up.

A Muscular and Cerebral Physiological Indices Assessment for Stress Measuring during Virtual Wheelchair Guidance.

The work presented in this manuscript has the purpose to assess the relationship between human factors and physiological indices. We discuss the relationship between stress as human factor and cerebral and muscular signals as features. Ten male paraplegic, right-handed subjects were volunteers for the experiment (mean age 34 ±6). They drove a virtual wheelchair in an indoor environment. They filled five missions where, in each one, an environmental parameter was changed. Meanwhile, they were equipped with Electromyography (EMG) sensors and Electroencephalography (EEG). Frequency and temporal features were filtered and extracted. Principal component analysis (PCA), Fisher's tests, repeated measure Anova and post hoc Tukey test (α = 0.05) were implemented for statistics. Environmental modifications are subject to induce stress, which impacts muscular and cerebral activities. While the time pressure parameter was the most influent, the transition from static to moving obstacles (avatars), tends to have a significant impact on stress levels. However, adding more moving obstacles did not show any impact. A synchronization factor was noticed between cerebral and muscular features in higher stress levels. Further examination is needed to assess EEG reliability in these situations.

Comparative study of preimplantation development following distinct assisted oocyte activation protocols in a PLC-zeta knockout mouse model.

Mammalian fertilization encompasses a series of Ca2+ oscillations initiated by the sperm factor phospholipase C zeta (PLCζ). Some studies have shown that altering the Ca2+ oscillatory regime at fertilization affects preimplantation blastocyst development. However, assisted oocyte activation (AOA) protocols can induce oocyte activation in a manner that diverges profoundly from the physiological Ca2+ profiling. In our study, we used the newly developed PLCζ-null sperm to investigate the independent effect of AOA on mouse preimplantation embryogenesis. Based on previous findings, we hypothesized that AOA protocols with Ca2+ oscillatory responses might improve blastocyst formation rates and differing Ca2+ profiles might alter blastocyst transcriptomes. A total of 326 MII B6D2F1-oocytes were used to describe Ca2+ profiles and to compare embryonic development and individual blastocyst transcriptomes between four control conditions: C1 (in-vivo fertilization), C2 (ICSI control sperm), C3 (parthenogenesis) and C4 (ICSI-PLCζ-KO sperm) and four AOA groups: AOA1 (human recombinant PLCζ), AOA2 (Sr2+), AOA3 (ionomycin) and AOA4 (TPEN). All groups revealed remarkable variations in their Ca2+ profiles; however, oocyte activation rates were comparable between the controls (91.1% ± 13.8%) and AOA (86.9% ± 11.1%) groups. AOA methods which enable Ca2+ oscillatory responses (AOA1: 41% and AOA2: 75%) or single Ca2+ transients (AOA3: 50%) showed no significantly different blastocyst rates compared to ICSI control group (C2: 70%). In contrast, we observed a significant decrease in compaction (53% vs. 83%) and blastocyst rates (41% vs. 70%) in the absence of an initial Ca2+ trigger (AOA4) compared with the C2 group. Transcription profiles did not identify significant differences in gene expression levels between the ICSI control group (C2) and the four AOA groups.

Mental fatigue level detection based on event related and visual evoked potentials features fusion in virtual indoor environment.

The purpose of this work is to set up a model that can estimate the mental fatigue of users based on the fusion of relevant features extracted from Positive 300 (P300) and steady state visual evoked potentials (SSVEP) measured by electroencephalogram. To this end, an experimental protocol describes the induction of P300, SSVEP and mental workload (which leads to mental fatigue by varying time-on-task) in different scenarios where environmental artifacts are controlled (obstacles number, obstacles velocities, ambient luminosity). Ten subjects took part in the experiment (with two suffering from cerebral palsy). Their mission is to navigate along a corridor from a starting point A to a goal point B where specific flickering stimuli are introduced to perform the P300 task. On the other hand, SSVEP task is elicited thanks to 10 Hz flickering lights. Correlated features are considered as inputs to fusion block which estimates mental workload. In order to deal with uncertainties and heterogeneity of P300 and SSVEP features, Dempster-Shafer (D-S) evidential reasoning is introduced. As the goal is to assess the reliability for the estimation of mental fatigue levels, D-S is compared to multi layer perception and linear discriminant analysis. The results show that D-S globally outperforms the other classifiers (although its performance significantly decreases between healthy and palsied groups). Finally we discuss the feasibility of such a fusion proposal in real life situation.

Sleep disordered breathing and nocturnal hypoxemia are very prevalent in a lung cancer screening population and may condition lung cancer screening findings: results of the prospective Sleep Apnea In Lung Cancer Screening (SAILS) study.

OBJECTIVE: Obstructive sleep apnea (OSA) can influence the appearance and proliferation of some tumors. The Sleep Apnea In Lung Cancer Screening (SAILS) study (NCT02764866) evaluated the prevalence of OSA and nocturnal hypoxemia in a high-risk population enrolled in a lung cancer screening program. METHODS: This was a prospective study of the prevalence of OSA in a lung cancer screening program. Subjects met the National Lung Screening Trial (NLST) age and smoking criteria (age 55-75 years; pack-years >30). Participants in the study were offered annual screening with low-dose computed tomography (LDCT) and pulmonary function testing, as well as home sleep apnea testing (HSAT) and a sleep-specific questionnaire. Sleep study-related variables, symptoms, and epidemiologic data were recorded. RESULTS: HSAT was offered to 279 subjects enrolled in our lung cancer screening program. HSAT results were available for 236 participants (mean age 63.6 years; mean tobacco exposure: 45 pack-years), of whom 59% were male and 53% were active smokers. Emphysema (74%) and chronic obstructive pulmonary disease (COPD) (62%) were common and in most cases mild in severity. OSA, including moderate to severe disease, was very common in this patient population. AHI distributions were as follows: AHI <5 (22.5%); 5-15 (36.4%); 15-30 (23.3%); and >30 (17.8%). Nocturnal hypoxemia (T90) (p = 0.003), diffusing capacity for carbon monoxide (DLCO) (p = 0.01), tobacco exposure (p = 0.024), and COPD (p = 0.023) were associated with OSA severity. Positive screening findings (nodules ≥6 mm) were associated with nocturnal hypoxemia on multivariate analysis adjusted for confounders (OR = 2.6, 95% CI = 1.12-6.09, p = 0.027). CONCLUSION: Moderate to severe OSA is very prevalent in patients enrolled in a lung cancer screening program. Nocturnal hypoxemia more than doubles the risk of positive screening findings.

Accuracy of patient-specific guided implantation of the glenoid component in reversed shoulder arthroplasty.

BACKGROUND: The aim of this study was to assess the accuracy of patient-specific guided glenoid component implantation in reverse shoulder arthroplasty. MATERIALS AND METHODS: 32 reverse shoulder arthroplasties were done using preoperative 3D planning and 4 patient-specific guides to prepare the glenoid and position the glenoid component. Baseplate version, inclination and entry point as well as angulation of the screws were compared to the preoperative plan measured on CT by independent observers. RESULTS: The mean deviation in baseplate version from the preoperative plan was 4.4°+3.1° (range, 0.3°-13.7°), in baseplate inclination 5.0°+4.2° (range, 0.1° to 14.5°) and in baseplate entry point 2.4mm+1.4mm (range, 0.4° to 6.3°). The average screw superior-inferior angulation deviation for the superior screw was 2.8°+2.6° (range, 0.0°-10.1°) and 2.8+2.6° in the antero-posterior plane (range, 0.1°-11.6°). For the inferior screw the superior-inferior angle deviation was 5.3°+3.8° (range, 0.1°-15.2°); the antero-posterior angle deviation was 4.1°+3.1° (range, 0.0°-9.8°). CONCLUSIONS: Patient-specific instrumentation (PSI) for the glenoid component in reverse shoulder arthroplasty allows the shoulder surgeon to accurately execute the preoperative 3D plan. LEVEL OF EVIDENCE: Level 3.

When mental fatigue maybe characterized by Event Related Potential (P300) during virtual wheelchair navigation.

The goal of this study is to investigate the influence of mental fatigue on the event related potential P300 features (maximum pick, minimum amplitude, latency and period) during virtual wheelchair navigation. For this purpose, an experimental environment was set up based on customizable environmental parameters (luminosity, number of obstacles and obstacles velocities). A correlation study between P300 and fatigue ratings was conducted. Finally, the best correlated features supplied three classification algorithms which are MLP (Multi Layer Perceptron), Linear Discriminate Analysis and Support Vector Machine. The results showed that the maximum feature over visual and temporal regions as well as period feature over frontal, fronto-central and visual regions were correlated with mental fatigue levels. In the other hand, minimum amplitude and latency features didn't show any correlation. Among classification techniques, MLP showed the best performance although the differences between classification techniques are minimal. Those findings can help us in order to design suitable mental fatigue based wheelchair control.

The effect of time pressure on stress levels during virtual wheelchair navigation.

In this work stress is assessed based on EEG features. We focus our efforts on the correlation between subjective ratings and cerebral indices during virtual navigation scenarios. Ten male paraplegic subjects took part in the experiment and navigated in a virtual indoor environment. They had to fulfill two missions where time pressure parameter is introduced. Subjects were equipped with Electroencephalography sensors. Temporal and frequency data were filtered and extracted. A correlation study was conducted based on principal component analysis, Fisher's tests and ANOVA. The results showed that the introduction of time pressure has a significant impact on stress levels.

Antiphospholipid antibody-mediated effects in an arterial model of thrombosis are dependent on Toll-like receptor 4.

Patients with antiphospholipid syndrome (APS) produce antiphospholipid antibodies (aPL) and develop vascular thrombosis that may occur in large or small vessels in the arterial or venous beds. On the other hand, many individuals produce aPL and yet never develop thrombotic events. Toll-like receptor 4 (TLR4) appears to be necessary for aPL-mediated prothrombotic effects in venous and microvascular models of thrombosis, but its role in arterial thrombosis has not been studied. Here, we propose that aPL alone are insufficient to cause thrombotic events in an arterial model of APS, and that a concomitant trigger of innate immunity (e.g. TLR4 activation) is required. We show specifically that anti-ß2-glycoprotein I (anti-ß2GPI) antibodies, a subset of aPL, accelerated thrombus formation in C57BL/6 wild-type, but not TLR4-deficient, mice in a ferric chloride-induced carotid artery injury model. These aPL bound to arterial and venous endothelial cells, particularly in the presence of ß2GPI, and to human TLR4 by enzyme-linked immunoassay. Arterial endothelium from aPL-treated mice had enhanced leukocyte adhesion, compared to control IgG-treated mice. In addition, aPL treatment of mice enhanced expression of tissue factor (TF) in leukocytes induced by the TLR4 ligand lipopolysaccharide (LPS). aPL also enhanced LPS-induced TF expression in human leukocytes in vitro. Our findings support a mechanism in which aPL enhance TF expression by leukocytes, as well as augment adhesion of leukocytes to the arterial endothelium. The activation of TLR4 in aPL-positive individuals may be required to trigger thrombotic events.

A primary role for kinin B1 receptor in inflammation, organ damage, and lethal thrombosis in a rat model of septic shock in diabetes.

Diabetes mellitus and septic shock increase the incidence of mortality by thrombosis. Although kinin B1 receptor (B1R) is involved in both pathologies, its role in platelet function and thrombosis remains unknown. This study investigates the expression, the inflammatory, and pro-thrombotic effects of B1R in a model of septic shock in diabetic rats. Sprague-Dawley rats were made diabetic with streptozotocin (STZ) (65 mg/kg, i.p.). Four days later, control and STZ-diabetic rats were injected with lipopolysaccharide (LPS) (2 mg/kg, i.p.) or the vehicle. B1R antagonist (SSR240612, 10 mg/kg by gavage) was given either acutely (12 and 24 h prior to endpoint analysis) or daily for up to 7 days. Moreover, a 7-day treatment was given either with cyclooxygenase (COX)-2 inhibitor (niflumic acid, 5 mg/kg, i.p.), non-selective COX-1 and COX-2 inhibitor (indomethacin, 10 mg/kg, i.p.), non-selective nitric oxide synthase (NOS) inhibitor (L-NAME, 50 mg/kg by gavage), iNOS inhibitor (1400W, 5 mg/kg, i.p.), or heparin (100 IU/kg, s.c.). The following endpoints were measured: edema and vascular permeability (Evans blue dye), B1R expression (qRT-PCR, western blot, flow cytometry), aggregation in platelet-rich plasma (optical aggregometry), and organ damage (histology). Rats treated with STZ, LPS, and STZ plus LPS showed significant increases in edema and vascular permeability (heart, kidney, lung, and liver) and increased expression of B1R in heart and kidney (mRNA) and platelets (protein). Lethal septic shock induced by LPS was enhanced in STZ-diabetic rats and was associated with lung and kidney damage, including platelet micro-aggregate formation. SSR240612 prevented all these abnormalities as well as STZ-induced hyperglycemia and LPS-induced hyperthermia. Similarly to SSR240612, blockade of iNOS and COX-2 improved survival. Data provide the first evidence that kinin B1R plays a primary role in lethal thrombosis in a rat model of septic shock in diabetes. Pharmacological rescue was made possible with B1R antagonism or by inhibition of iNOS and COX-2, which may act as downstream mechanisms.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and Alzheimer's disease.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a ubiquitous enzyme that catalyzes the sixth step of glycolysis and thus, serves to break down glucose for energy production. Beyond the traditional aerobic metabolism of glucose, recent studies have highlighted additional roles played by GAPDH in non-metabolic processes, such as control of gene expression and redox post-translational modifications. Neuroproteomics have revealed high affinity interactions between GAPDH and Alzheimer's disease-associated proteins, including the ß-amyloid, ß-amyloid precursor protein and tau. This neuronal protein interaction may lead to impairment of the GAPDH glycolytic function in Alzheimer's disease and may be a forerunner of its participation in apoptosis. The present review examines the crucial implication of GAPDH in neurodegenerative processes and clarifies its role in apoptotic cell death.

Novel presenilin mutations within Moroccan patients with Early-Onset Alzheimer's Disease.

Alzheimer's disease (AD) is a progressive brain disorder that causes gradual and irreversible loss of higher brain functions and is the most common cause of dementia in the elderly, as assessed by autopsy and clinical series. Furthermore, it has an annual incidence of approximately 3% in the 65-74-year-old age group. This incidence rate doubles with every increment of 5 years above the age of 65. In Morocco, AD affects almost 30,000 individuals and this number will possibly increase to 75,000 by 2020 (projections of the World Health Organization (WHO)). Genetically, AD is caused by a mutation in one of at least 3 genes: presenilin 1 (PS1), presenilin 2 (PS2) and the amyloid precursor protein (APP). Most cases are late onset and apparently sporadic, most likely as a result of a combination of environmental and non-dominant genetic factors. In Morocco, the genes predisposing individuals to AD and predicting disease incidence remain elusive. The purpose of the present study was to evaluate the genetic contribution of mutations in PS1 and PS2 genes to familial early-onset AD cases and sporadic late-onset AD cases. Seventeen sporadic late-onset AD cases and eight familial early-onset AD cases were seen at the memory clinic of the University of Casablanca Neurology Department. These patients underwent standard somatic neurological examination, cognitive function assessment, brain imaging and laboratory tests. Direct sequencing of each exon in PS1 and PS2 genes was performed on genomic DNA of AD patients. Further, we identified 1 novel frameshift mutation in the PS1 gene and 2 novel frameshift mutations in the PS2 gene. Our mutational analysis reports a correlation between clinical symptoms and genetic factors in our cases of Early-Onset Alzheimer's Disease (EOAD). These putative mutations cosegregate with affected family members suggesting a direct mutagenic effect.

Influence of mental fatigue on P300 and SSVEP during virtual wheelchair navigation.

The aim of this paper is to investigate the influence of mental fatigue on Positive 300 (P300) and Steady State Visual Evoked Potentials (SSVEP) during virtual wheelchair navigation. For this purpose, experimental protocols were setup in order to induce mental fatigue, P300 and SSVEP. Next, the correlation between mental fatigue and P300/SSVEP parameters were investigated. At the end, the best correlated features from both modalities were used as inputs for three classification techniques. Depending on the subject samples (healthy vs palsy), The best overall classification rate reached 80% for P300 modality. The results of this investigation constitute the first steps towards an anticipatory system that can assist the wheelchair driver during navigation, depending on his mental fatigue level.

Soluble CD40 ligand impairs the anti-platelet function of peripheral blood angiogenic outgrowth cells via increased production of reactive oxygen species.

Adult peripheral blood angiogenic early outgrowth cells (EOCs), also known as early endothelial progenitor cells, interact with other blood and vascular cells and may regulate atherothrombosis. We have previously shown that endothelial progenitor cells inhibit platelet function and thrombus formation. The CD40L/CD40 axis is a thrombo- inflammatory mediator that affects platelet and endothelial functions. It has been shown that EOCs express CD40, whereas platelets represent the major source of its soluble ligand (sCD40L), which impairs EOC function.We aimed to test the hypothesis that the sCD40L/CD40 axis affects the anti-platelet function of EOCs. Human peripheral blood mononuclear cell-derived EOCs in culture inhibited platelet aggregation. Pre-treatment of EOCs with sCD40L reduced their inhibitory effect on platelet aggregation in a CD40-dependent manner. EOCs viability and release of the anti-aggregating agents, prostacyclin and nitric oxide, were not affected by sCD40L. However, production of reactive oxygen species (ROS) was increased in sCD40L-treated EOCs. Blockade of ROS reversed the effects of sCD40L-treated EOCs on platelet aggregation. This study reveals that the sCD40L/CD40 axis impairs the anti-platelet properties of EOCs through increased production of ROS. These data may explain the link between elevated levels of sCD40L, impaired activity of EOCs and enhanced platelet reactivity, and consequently the occurrence of atherothrombotic disease.

Phosphorylation of MCT-1 by p44/42 MAPK is required for its stabilization in response to DNA damage.

We discovered a novel oncogene in a T-cell lymphoma cell line, multiple copies in T-cell lymphoma-1 (MCT-1), that has been shown to decrease cell-doubling time, shorten the duration of G(1) transit time and/or G(1)-S transition, and transform NIH3T3 fibroblasts. We subsequently demonstrated that there were significantly increased levels of MCT-1 protein in a subset of primary diffuse large B-cell lymphomas. Levels of MCT-1 protein were shown to be increased after exposure to DNA damaging agents. This increase did not require new protein synthesis, suggesting that post-translational mechanisms were involved. Phosphorylation is one potential mechanism by which the activity of molecules involved in cell cycle/survival is rapidly modulated. The RAS/mitogen-activated/extracellular-regulated kinase (MEK)/extracellular signal-regulated kinases (ERK) pathway plays a prominent role in the regulation of cell growth and proliferation through phosphorylation-dependent regulation of several substrates. The MCT-1 protein is predicted to have numerous putative phosphorylation sites. Using a combination of genetic and pharmacological approaches, we established that phosphorylation of MCT-1 protein by p44/p42 mitogen-activated protein kinases is critical for stabilization of MCT-1 protein and for its ability to promote cell proliferation. Our data suggests that targeting the RAS/MEK/ERK signal transduction cascade may provide a potential therapeutic approach in lymphomas and related malignancies that exhibit high levels of MCT-1 protein.

[Screw fixation without bone graft of calcaneal joint fractures: 35 cases]. / Résultats de l'ostéosynthèse par vissage sans greffe osseuse des fractures articulaires du calcaneus: à propos de 35 cas.

PURPOSE OF THE STUDY: The prognosis of calcaneal joint fractures is less favorable than fractures without joint involvement. Surgical treatment is frequently recommended. The type of fixation and the usefulness of a bone graft remain subjects of debate. The purpose of this work was to present the functional and anatomic results obtained with simple screw fixation without bone grafting in a retrospective series of 35 displaced joint fractures of the calcaneus. MATERIAL AND METHODS: The series included 31 patients (four bilateral fractures), 86% men. Mean age was 36 years (17-60 years). Using the Duparc classification, there were 12% type III fractures and 88% type IV fractures. Horizontal joint impaction was observed in 36% of patients, vertical impaction in 8%, and mixted impaction in 56%. The mean Bohler angle was 2 degrees (range -25 degrees to 15 degrees ). According to the Utheza classification, 70% of the fractures had two sagittal fracture lines, 16.5% one sagittal fracture line, and 13.5% comminutive fractures. Incongruency of the subtalar joint was noted in 70%, with a conflict with the lateral malleolus in 50%. Mean time to surgery was 12 days (7-30 days). The sub- and retromalleolar approach was used to achieve simple screw fixation. Bone grafts were not used. Mean follow-up was two years (range 12-38 months). RESULTS: There were no serious complications. Functional outcome was analyzed with the Kitaoka scale, mean score 74.3 +/- 1.1 (range 46-98), with 16% excellent outcome, 56% good outcome, 25.2% fair outcome, and 2.5% poor outcome. There was a correlation between functional outcome and age, etiology, and type of fracture. Anatomic results were assessed with the Babin scale and were very good in 24%, good in 8%, fair in 28%, and poor in 40%. Secondary loss of the initial heightening of the joint surface was noted in 48% of the cases, 3 degrees on average. DISCUSSION: This series confirms the value of surgical treatment compared with conservative treatment. Compared with plate fixation, screw fixation exposes the patient to less risk of skin and infectious problems. Simple screwing generally provides satisfactory results with acceptable stability. In light of the present results, adjunction of a bone graft would not be necessary since the loss of correction of the joint surface height was often minimal. CONCLUSION: Screw fixation of calcaneal joint fractures is a reliable technique. Adjunction of a bone graft does not appear to be necessary.

Monte Carlo simulation of a medical linear accelerator for radiotherapy use.

A Monte Carlo code MCNPX (Monte Carlo N-particle) was used to model a 25 MV photon beam from a PRIMUS (KD2-Siemens) medical linear electron accelerator at the Centre Antoine Lacassagne in Nice. The entire geometry including the accelerator head and the water phantom was simulated to calculate the dose profile and the relative depth-dose distribution. The measurements were done using an ionisation chamber in water for different square field ranges. The first results show that the mean electron beam energy is not 19 MeV as mentioned by Siemens. The adjustment between the Monte Carlo calculated and measured data is obtained when the mean electron beam energy is approximately 15 MeV. These encouraging results will permit to check calculation data given by the treatment planning system, especially for small fields in high gradient heterogeneous zones, typical for intensity modulated radiation therapy technique.