Use of trochanteric nail for proximal femoral extracapsular fractures

Résumé Les fractures extra capsulaires du fémur proximal sont connues pour le risque élevé de morbidité et de mortalité en cas de traitement non chirurgical. Ainsi, le clou Gamma standard a été produit pour garantir une fixation stable de ces fractures permettant par conséquent une mobilisation rapide et en charge des personnes en âge avancé et présentant ce genre de fracture. Mais il a été reproché à ce type de clou un nombre relativement élevé de fracture per ou post opératoire (environ 17%). Cette complication est liée au design de cet implant. Et, de ce fait, le clou Trochantéric a été créé pour remédier à cette complication en changeant la forme du clou et notamment sa courbure. Entre juillet 2000 et janvier 2001, 88 patients ont été traités par clou Trochantéric pour une fracture pertrochantérienne et suivis consécutivement dans notre Service. 75 patients, soit 76 fractures, ont pu être évalués cliniquement et radiologiquement durant une évolution de deux ans.

Noms que formen part d'un determinant complex

Aquest article examina un aspecte de la informació gramatical que inclouen els diccionaris. En concret, analitza el tractament lexicogràfic que els noms que poden formar part d'un determinant complex han rebut en diversos diccionaris. Són noms que, segons els contextos funcionen com a nucli d'un sintagma nominal o com a nucli d'un sintagma determinant. Els resultats d'aquest estudi demostren que la informació gramatical en aquest tipus de noms en la majoria de diccionaris és molt pobre i fins i tot nul·la. Com a alternativa, el treball proposa un primer disseny d'entrada lexicogràfica prototípica per aquest tipus de noms que al costat de la informació semàntica té en compte la informació gramatical i la informació pragmàtica.

Closed and open grade I and II tibial shaft fractures treated by reamed intramedullary nailing

RESUME Objectif : Le but de cette étude est d'évaluer les résultats du traitement par enclouage centre-médullaire alésé des fractures diaphysaires du tibia aussi bien fermées que pour les fractures ouvertes de stade I et II selon Gustillo. Méthodes: Entre 1997 et 2000, 119 patients présentant une fracture diaphysaire du tibia ont été traités dans notre service par un enclouage centre-médullaire alésé. En postopératoire, 96 patients, soit 70 fractures fermées et 26 fractures ouvertes I et II selon Gustillo, ont été suivis cliniquement et radiologiquement pour une période de plus d'une année et demi. L'introduction du clou centro-médullaire a été faite selon la technique habituelle, soit transtendineuse ou paratendineusé rotulienne. Tous les clous ont été alésés jusqu'à 1,5 mm au-dessus du diamètre du clou. Les patients ayant une fracture isolée du tibia ont été immédiatement mobilisés en charge partielle pour une période de 6 semaines. Ceux qui avaient des lésions associées, notamment au niveau de la cheville épsilatérale, ont nécessité la mise en place d'un plâtre de Type Sarmiento. Résultats : Six patients (6,3%) ont développé un syndrome des loges après chirurgie. Quarante-huit cas (50%) ont nécessité une dynamisation du clou après une période moyenne de 12 semaines en raison d'un retard de consolidation. En général, 90,6% des fractures ont consolidé après 24 semaines postopératoires en moyenne, sans aucune différence significative entre les fractures fermées et les fractures ouvertes. Deux patients (2,1 %) présentant une fracture ouverte degré II ont développé une infection profonde ayant nécessité un traitement. Nous avons également observé 9,4% de cals vicieux minimes et sans conséquence clinique. Huit patients (8,3%) ont eu une brisure des vis de .verrouillage mais également sans conséquence clinique. Au dernier contrôle, 52% des patients, dont ('introduction du clou s'est faite en transtendineux ont des douleurs antérieures du genou contre 14% parmi ceux où l'introduction était paratendineuse. Conclusion : L'enclouage centre-médullaire reste le traitement de choix pour les fractures diaphysaires du tibia, qu'elles soient fermées ou ouvertes degré I ou II selon Gustillo.

The SM protein Sly1 accelerates assembly of the ER-Golgi SNARE complex.

Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) and Sec1/Munc18 (SM) proteins constitute the core of an ancient vesicle fusion machine that diversified into distinct sets that now function in different trafficking steps in eukaryotic cells. Deciphering their precise mode of action has proved challenging. SM proteins are thought to act primarily through one type of SNARE protein, the syntaxins. Despite high structural similarity, however, contrasting binding modes have been found for different SM proteins and syntaxins. Whereas the secretory SM protein Munc18 binds to the ‟closed conformation" of syntaxin 1, the ER-Golgi SM protein Sly1 interacts only with the N-peptide of Sed5. Recent findings, however, indicate that SM proteins might interact simultaneously with both syntaxin regions. In search for a common mechanism, we now reinvestigated the Sly1/Sed5 interaction. We found that individual Sed5 adopts a tight closed conformation. Sly1 binds to both the closed conformation and the N-peptide of Sed5, suggesting that this is the original binding mode of SM proteins and syntaxins. In contrast to Munc18, however, Sly1 facilitates SNARE complex formation by loosening the closed conformation of Sed5.

Alpine tectonic evolution of a Jurassic subduction-accretionary complex: Deformation, kinematics and 40Ar/39Ar age constraints on the Mesozoic low-grade schists of the Circum-Rhodope Belt in the eastern Rhodope-Thrace region, Bulgaria-Greece

Deformation of the Circum-Rhodope Belt Mesozoic (Middle Triassic to earliest Lower Cretaceous) low-grade schists underneath an arc-related ophiolitic magmatic suite and associated sedimentary successions in the eastern Rhodope-Thrace region occurred as a two-episode tectonic process: (i) Late Jurassic deformation of arc to margin units resulting from the eastern Rhodope-Evros arc-Rhodope terrane continental margin collision and accretion to that margin, and (ii) Middle Eocene deformation related to the Tertiary crustal extension and final collision resulting in the closure of the Vardar ocean south of the Rhodope terrane. The first deformational event D-1 is expressed by Late Jurassic NW-N vergent fold generations and the main and subsidiary planar-linear structures. Although overprinting, these structural elements depict uniform bulk north-directed thrust kinematics and are geometrically compatible with the increments of progressive deformation that develops in same greenschist-facies metamorphic grade. It followed the Early-Middle Jurassic magmatic evolution of the eastern Rhodope-Evros arc established on the upper plate of the southward subducting Maliac-Meliata oceanic lithosphere that established the Vardar Ocean in a supra-subduction back-arc setting. This first event resulted in the thrust-related tectonic emplacement of the Mesozoic schists in a supra-crustal level onto the Rhodope continental margin. This Late Jurassic-Early Cretaceous tectonic event related to N-vergent Balkan orogeny is well-constrained by geochronological data and traced at a regional-scale within distinct units of the Carpatho-Balkan Belt. Following subduction reversal towards the north whereby the Vardar Ocean was subducted beneath the Rhodope margin by latest Cretaceous times, the low-grade schists aquired a new position in the upper plate, and hence, the Mesozoic schists are lacking the Cretaceous S-directed tectono-metamorphic episode whose effects are widespread in the underlying high-grade basement. The subduction of the remnant Vardar Ocean located behind the colliding arc since the middle Cretaceous was responsible for its ultimate closure, Early Tertiary collision with the Pelagonian block and extension in the region caused the extensional collapse related to the second deformational event D-2. This extensional episode was experienced passively by the Mesozoic schists located in the hanging wall of the extensional detachments in Eocene times. It resulted in NE-SW oriented open folds representing corrugation antiforms of the extensional detachment surfaces, brittle faulting and burial history beneath thick Eocene sediments as indicated by 42.1-39.7 Ma Ar-40/Ar-39 mica plateau ages obtained in the study. The results provide structural constraints for the involvement components of Jurassic paleo-subduction zone in a Late Jurassic arc-continental margin collisional history that contributed to accretion-related crustal growth of the Rhodope terrane. (C) 2011 Elsevier Ltd. All rights reserved.

The A-kinase anchoring protein (AKAP)-Lbc-signaling complex mediates alpha1 adrenergic receptor-induced cardiomyocyte hypertrophy.

In response to various pathological stresses, the heart undergoes a pathological remodeling process that is associated with cardiomyocyte hypertrophy. Because cardiac hypertrophy can progress to heart failure, a major cause of lethality worldwide, the intracellular signaling pathways that control cardiomyocyte growth have been the subject of intensive investigation. It has been known for more than a decade that the small molecular weight GTPase RhoA is involved in the signaling pathways leading to cardiomyocyte hypertrophy. Although some of the hypertrophic pathways activated by RhoA have now been identified, the identity of the exchange factors that modulate its activity in cardiomyocytes is currently unknown. In this study, we show that AKAP-Lbc, an A-kinase anchoring protein (AKAP) with an intrinsic Rho-specific guanine nucleotide exchange factor activity, is critical for activating RhoA and transducing hypertrophic signals downstream of alpha1-adrenergic receptors (ARs). In particular, our results indicate that suppression of AKAP-Lbc expression by infecting rat neonatal ventricular cardiomyocytes with lentiviruses encoding AKAP-Lbc-specific short hairpin RNAs strongly reduces both alpha1-AR-mediated RhoA activation and hypertrophic responses. Interestingly, alpha1-ARs promote AKAP-Lbc activation via a pathway that requires the alpha subunit of the heterotrimeric G protein G12. These findings identify AKAP-Lbc as the first Rho-guanine nucleotide exchange factor (GEF) involved in the signaling pathways leading to cardiomyocytes hypertrophy.

Outcome after surgical treatment of symptomatic delayed unions and nonunions of midshaft clavicle fractures

Introduction: Nonoperative treatment of displaced midshaft clavicle fractures is associated with higher nonunion rate than previously reported. Moreover, its occurrence can compromise shoulder function. The aim of this study was to evaluate the outcome of surgical treatment of symptomatic clavicle midshaft delayed and nonunion. Methods: Between 1999 and 2008, 19 clavicle delayed unions and nonunions were treated by open reduction and reconstructive plate fixation with augmentation by autologous bone graft. Iliac bone graft was used in 15 atrophic cases, and graft from the callus was used in 4 hypertrophic nonunions. There were 14 men and 5 women, with an average age of 41 years (range, 19 to 59 years) at time of surgery. No patient had undergone a previous surgery and all complained of shoulder pain. Delayed unions and nonunions were defined as non-healing after 3 and 6 months respectively. The mean time to surgery was 8 months (range, 4 to 23 months). All patients were pre and postoperatively clinically evaluated and imaged with standard radiographs until complete healing. Results: After a mean time of 3 months (range, 2 to 7 months) all fractures were completely healed. All patients reported full range of motion at time of last follow-up. Nine patients (47%) reported slight shoulder pain but all returned to their previous professional activities after a mean time of 3 months (range, 1 to 8 months). We reported 12 (63%) minor complications. There were 6 (32%) plate-related discomforts which resolved after hardware removal, two (11%) scar numbness, two (11%) adhesive capsulitis with spontaneous complete recovery, and two (11%) AC-joint pain treated successfully with local corticosteroids injection. Conclusion: Surgical treatment of delayed unions and nonunions of midshaft clavicle fractures yields satisfactory results and a high union rate. However, 50% of the patients may still complain of slight residual shoulder pain.

Towards robust network based complex systems : from evolutionary cellular automata to biological models

Abstract Sitting between your past and your future doesn't mean you are in the present. Dakota Skye Complex systems science is an interdisciplinary field grouping under the same umbrella dynamical phenomena from social, natural or mathematical sciences. The emergence of a higher order organization or behavior, transcending that expected of the linear addition of the parts, is a key factor shared by all these systems. Most complex systems can be modeled as networks that represent the interactions amongst the system's components. In addition to the actual nature of the part's interactions, the intrinsic topological structure of underlying network is believed to play a crucial role in the remarkable emergent behaviors exhibited by the systems. Moreover, the topology is also a key a factor to explain the extraordinary flexibility and resilience to perturbations when applied to transmission and diffusion phenomena. In this work, we study the effect of different network structures on the performance and on the fault tolerance of systems in two different contexts. In the first part, we study cellular automata, which are a simple paradigm for distributed computation. Cellular automata are made of basic Boolean computational units, the cells; relying on simple rules and information from- the surrounding cells to perform a global task. The limited visibility of the cells can be modeled as a network, where interactions amongst cells are governed by an underlying structure, usually a regular one. In order to increase the performance of cellular automata, we chose to change its topology. We applied computational principles inspired by Darwinian evolution, called evolutionary algorithms, to alter the system's topological structure starting from either a regular or a random one. The outcome is remarkable, as the resulting topologies find themselves sharing properties of both regular and random network, and display similitudes Watts-Strogtz's small-world network found in social systems. Moreover, the performance and tolerance to probabilistic faults of our small-world like cellular automata surpasses that of regular ones. In the second part, we use the context of biological genetic regulatory networks and, in particular, Kauffman's random Boolean networks model. In some ways, this model is close to cellular automata, although is not expected to perform any task. Instead, it simulates the time-evolution of genetic regulation within living organisms under strict conditions. The original model, though very attractive by it's simplicity, suffered from important shortcomings unveiled by the recent advances in genetics and biology. We propose to use these new discoveries to improve the original model. Firstly, we have used artificial topologies believed to be closer to that of gene regulatory networks. We have also studied actual biological organisms, and used parts of their genetic regulatory networks in our models. Secondly, we have addressed the improbable full synchronicity of the event taking place on. Boolean networks and proposed a more biologically plausible cascading scheme. Finally, we tackled the actual Boolean functions of the model, i.e. the specifics of how genes activate according to the activity of upstream genes, and presented a new update function that takes into account the actual promoting and repressing effects of one gene on another. Our improved models demonstrate the expected, biologically sound, behavior of previous GRN model, yet with superior resistance to perturbations. We believe they are one step closer to the biological reality.

A coiled coil trigger site is essential for rapid binding of synaptobrevin to the SNARE acceptor complex.

Exocytosis from synaptic vesicles is driven by stepwise formation of a tight alpha-helical complex between the fusing membranes. The complex is composed of the three SNAREs: synaptobrevin 2, SNAP-25, and syntaxin 1a. An important step in complex formation is fast binding of vesicular synaptobrevin to the preformed syntaxin 1.SNAP-25 dimer. Exactly how this step relates to neurotransmitter release is not well understood. Here, we combined different approaches to gain insights into this reaction. Using computational methods, we identified a stretch in synaptobrevin 2 that may function as a coiled coil "trigger site." This site is also present in many synaptobrevin homologs functioning in other trafficking steps. Point mutations in this stretch inhibited binding to the syntaxin 1.SNAP-25 dimer and slowed fusion of liposomes. Moreover, the point mutations severely inhibited secretion from chromaffin cells. Altogether, this demonstrates that the trigger site in synaptobrevin is crucial for productive SNARE zippering.

Assessment of volumetric bone mineral density of the femoral neck in postmenopausal women with and without vertebral fractures using quantitative multi-slice CT.

OBJECTIVE: To demonstrate the validity and reliability of volumetric quantitative computed tomography (vQCT) with multi-slice computed tomography (MSCT) and dual energy X-ray absorptiometry (DXA) for hip bone mineral density (BMD) measurements, and to compare the differences between the two techniques in discriminating postmenopausal women with osteoporosis-related vertebral fractures from those without. METHODS: Ninety subjects were enrolled and divided into three groups based on the BMD values of the lumbar spine and/or the femoral neck by DXA. Groups 1 and 2 consisted of postmenopausal women with BMD changes <-2SD, with and without radiographically confirmed vertebral fracture (n=11 and 33, respectively). Group 3 comprised normal controls with BMD changes > or =-1SD (n=46). Post-MSCT (GE, LightSpeed16) scan reconstructed images of the abdominal-pelvic region, 1.25 mm thick per slice, were processed by OsteoCAD software to calculate the following parameters: volumetric BMD values of trabecular bone (TRAB), cortical bone (CORT), and integral bone (INTGL) of the left femoral neck, femoral neck axis length (NAL), and minimum cross-section area (mCSA). DXA BMD measurements of the lumbar spine (AP-SPINE) and the left femoral neck (NECK) also were performed for each subject. RESULTS: The values of all seven parameters were significantly lower in subjects of Groups 1 and 2 than in normal postmenopausal women (P<0.05, respectively). Comparing Groups 1 and 2, 3D-TRAB and 3D-INTGL were significantly lower in postmenopausal women with vertebral fracture(s) [(109.8+/-9.61) and (243.3+/-33.0) mg/cm3, respectively] than in those without [(148.9+/-7.47) and (285.4+/-17.8) mg/cm(3), respectively] (P<0.05, respectively), but no significant differences were evident in AP-SPINE or NECK BMD. CONCLUSION: the femoral neck-derived volumetric BMD parameters using vQCT appeared better than the DXA-derived ones in discriminating osteoporotic postmenopausal women with vertebral fractures from those without. vQCT might be useful to evaluate the effect of osteoporotic vertebral fracture status on changes in bone mass in the femoral neck.

Pivotal role for a tail subunit of the RNA polymerase II mediator complex CgMed2 in azole tolerance and adherence in Candida glabrata.

Antifungal therapy failure can be associated with increased resistance to the employed antifungal agents. Candida glabrata, the second most common cause of invasive candidiasis, is intrinsically less susceptible to the azole class of antifungals and accounts for 15% of all Candida bloodstream infections. Here, we show that C. glabrata MED2 (CgMED2), which codes for a tail subunit of the RNA polymerase II Mediator complex, is required for resistance to azole antifungal drugs in C. glabrata. An inability to transcriptionally activate genes encoding a zinc finger transcriptional factor, CgPdr1, and multidrug efflux pump, CgCdr1, primarily contributes to the elevated susceptibility of the Cgmed2Δ mutant toward azole antifungals. We also report for the first time that the Cgmed2Δ mutant exhibits sensitivity to caspofungin, a constitutively activated protein kinase C-mediated cell wall integrity pathway, and elevated adherence to epithelial cells. The increased adherence of the Cgmed2Δ mutant was attributed to the elevated expression of the EPA1 and EPA7 genes. Further, our data demonstrate that CgMED2 is required for intracellular proliferation in human macrophages and modulates survival in a murine model of disseminated candidiasis. Lastly, we show an essential requirement for CgMed2, along with the Mediator middle subunit CgNut1 and the Mediator cyclin-dependent kinase/cyclin subunit CgSrb8, for the high-level fluconazole resistance conferred by the hyperactive allele of CgPdr1. Together, our findings underscore a pivotal role for CgMed2 in basal tolerance and acquired resistance to azole antifungals.

Intraoral open reduction and internal fixation of displaced mandibular angle fractures using a specific ad hoc reduction-compression forceps: a preliminary study

OBJECTIVES: To preliminarily evaluate prospectively the accuracy and reliability of a specific ad hoc reduction-compression forceps in intraoral open reduction of transverse and displaced mandibular angle fractures. STUDY DESIGN: We analyzed the clinical and radiologic data of 7 patients with 7 single transverse and displaced angle fractures. An intraoral approach was performed in all of the patients without using perioperative intermaxillary fixation. A single Arbeitsgemeinschaft Osteosynthese (AO) unilock reconstruction plate was fixed to each stable fragment with 3 locking screws (2.0 mm in 5 patients and 2.4 mm in 2 patients) at the basilar border of the mandible, according to AO/American Society of Internal Fixation (ASIF) principles. Follow-up was at 1, 3, 6, and 12 months, and we noted the status of healing and complications, if any. RESULTS: All of the patients had satisfactory fracture reduction as well as a successful treatment outcome without complications. CONCLUSION: This preliminary study demonstrated that the intraoral reduction of transverse and displaced angle fractures using a specific ad hoc reduction-forceps results in a high rate of success.

The AO comprehensive classification of pediatric long-bone fractures: a web-based multicenter agreement study.

The first AO comprehensive pediatric long-bone fracture classification system has been proposed following a structured path of development and validation with experienced pediatric surgeons. A Web-based multicenter agreement study involving 70 surgeons in 15 clinics and 5 countries was conducted to assess the reliability and accuracy of this classification when used by a wide range of surgeons with various levels of experience. Training was provided at each clinic before the session. Using the Internet, participants could log in at any time and classify 275 supracondylar, radius, and tibia fractures at their own pace. The fracture diagnosis was made following the hierarchy of the classification system using both clinical terminology and codes. kappa coefficients for the single-surgeon diagnosis of epiphyseal, metaphyseal, or diaphyseal fracture type were 0.66, 0.80, and 0.91, respectively. Median accuracy estimates for each bone and type were all greater than 80%. Depending on their experience and specialization, surgeons greatly varied in their ability to classify fractures. Pediatric training and at least 2 years of experience were associated with significant improvement in reliability and accuracy. Kappa coefficients for diagnosis of specific child patterns were 0.51, 0.63, and 0.48 for epiphyseal, metaphyseal, and diaphyseal fractures, respectively. Identified reasons for coding discrepancies were related to different understandings of terminology and definitions, as well as poor quality radiographic images. Results supported some minor adjustments in the coding of fracture type and child patterns. This classification system received wide acceptance and support among the surgeons involved. As long as appropriate training could be performed, the system classification was reliable, especially among surgeons with a minimum of 2 years of clinical experience. We encourage broad-based consultation between surgeons' international societies and the use of this classification system in the context of clinical practice as well as prospectively for clinical studies.

Comparison between standard radiography and spiral CT with 3D reconstruction in the evaluation, classification and management of tibial plateau fractures.

The aim of this study was to compare the diagnostic efficiency of plain film and spiral CT examinations with 3D reconstructions of 42 tibial plateau fractures and to assess the accuracy of these two techniques in the pre-operative surgical plan in 22 cases. Forty-two tibial plateau fractures were examined with plain film (anteroposterior, lateral, two obliques) and spiral CT with surface-shaded-display 3D reconstructions. The Swiss AO-ASIF classification system of bone fracture from Muller was used. In 22 cases the surgical plans and the sequence of reconstruction of the fragments were prospectively determined with both techniques, successively, and then correlated with the surgical reports and post-operative plain film. The fractures were underestimated with plain film in 18 of 42 cases (43%). Due to the spiral CT 3D reconstructions, and precise pre-operative information, the surgical plans based on plain film were modified and adjusted in 13 cases among 22 (59%). Spiral CT 3D reconstructions give a better and more accurate demonstration of the tibial plateau fracture and allows a more precise pre-operative surgical plan.