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Fragmentation of large continental areas by post-orogenic extension requires favourable geodynamic conditions and frequently occurs along pre-existing suture zones or nappe contacts, as exemplified by the Stong and Taku magmatic and metamorphic complexes of northern Peninsular Malaysia. For this case, we have employed a field and microstructural kinematic study combined with low temperature thermo-chronology to analyse the tectonic and exhumation history. The results show that the Late Palaeozoic - Triassic Indosinian orogeny created successive phases of burial related metamorphism, shearing and contractional deformation. This orogenic structure was subsequently dismembered during a Cretaceous thermal event that culminated in the formation of a large scale Late Santonian - Early Maastrichtian extensional detachment, genetically associated with crustal melting, the emplacement of syn-kinematic plutons and widespread migmatisation. The emplacement of these magmatic rocks led to an array of simultaneously formed structures that document deformation conditions over a wide temperature range, represented by amphibolite- and greenschist- facies mylonites and as well as brittle structures, such as cataclastic zones and normal faults that formed during exhumation in the footwall of the detachment. The formation of this detachment and a first phase of Late Cretaceous cooling was followed by renewed Eocene - Oligocene exhumation, as evidenced from our fission track ages. We infer that an initial Cretaceous thermal anomaly was responsible for the formation of an extensional gneiss dome associated with simple shear and rotation of normal faults. These Cretaceous processes played a critical role in the establishment of the presently observed crustal structure of Peninsular Malaysia. [ABSTRACT FROM AUTHOR]

Coronary intervention for myocardial infarction often results in microvascular embolization of thrombus. Sonoreperfusion therapy (SRP) using ultrasound and microbubbles restored perfusion in our in vitro flow model of microvascular obstruction. In this study, we assessed SRP efficacy using whole blood as the perfusate with and without tissue plasminogen activator (tPA). In a phantom vessel bearing a 40-μm-pore mesh to simulate the microvasculature, microthrombi were injected to cause microvascular obstruction and were treated using SRP. Without tPA, the lytic rate increased from 2.6 ± 1.5 mmHg/min with 1000-cycle pulses to 7.3 ± 3.2 mmHg/min with 5000-cycle ultrasound pulses (p < 0.01). The lytic index was similar for tPA-only ([2.0 ± 0.5] × 10-3 mmHg-1 min-1) and 5000 cycles without tPA ([2.3 ± 0.5] × 10-3 mmHg-1 min-1) (p = 0.5) but increased ([3.6 ± 0.8] × 10-3 mmHg-1 min-1) with tPA in conjunction with 5000-cycles ultrasound (p < 0.01). In conclusion, SRP restored microvascular perfusion in whole blood, SRP lytic rate in experiments without tPA increased with ultrasound pulse length and efficacy increased with the addition of tPA. [ABSTRACT FROM AUTHOR]

Abstract: After total hip arthroplasty (THA) some patients have persistent postoperative pain (POP). Some of these POP are anterior and are caused by an anterior iliopsoas impingement (AIPI). We have hypothesized that oversized implanted cups could be responsible for POP and especially AIPI. We screened 237 patients who had a primary THA and compared the size difference (ΔS) between the native femoral head and the implanted cup, in patients with and without POP. Median ΔS was 2mm [−6; 11mm] and patients with POP had a significantly increased ΔS (P <0.0001). The threshold above which pain was significantly more frequent was ΔS≥6mm. Odds ratio was 14.4 for POP and 26 for AIPI pain when ΔS ≥6mm. [Copyright &y& Elsevier]

Abstract: Aim: This study aimed to evaluate patient information provided, the management of post-operative symptoms and post-operative care, and patient satisfaction with ambulatory breast surgery over a 1-year period. Methods: From January to December 2000, all breast cancer patients undergoing conservative breast surgery were offered surgery as an outpatient procedure at the Ambulatory Surgery Unit. Results: Two hundred and thirty six patients underwent outpatient surgery. None were readmitted during the first night or the first week. Two hundred and nineteen patients completed a questionnaire. One hundred and sixty nine patients (group 1) underwent wide local excision (WLE) and 50 (group 2), WLE and axillary lymphadenectomy. Patients in group 2 experienced more pain at discharge from the hospital (p≤0.01) and during the first week after discharge (p≤0.00001) than patients in group 1. The mean overall satisfaction score was 8.97 on a scale of 1–10. Post-operative information provided by the surgeon before discharge from the hospital was rated 8.90 on a scale of 1–10 while information provided by the nurse was rated 9.33 (p<0.0001). Conclusion: Ambulatory surgery for breast cancer patients is safe and popular with patients, however, post-operative pain presents problem. [Copyright &y& Elsevier]

Highlights • Laryngeal haematoma has not previously been described in an obstetric patient. • This rare condition can be life-threatening. • It presents quickly as dyspnoea, dysphagia, neck pain and dysphonia. • Differential diagnoses include anaphylaxis or other oropharyngeal pathology. • Treatment consists of conservative management of acute dyspnoea. [ABSTRACT FROM AUTHOR]

Summary: Introduction: Ambulatory breast surgery is not well developed in France. This is especially true for oncologic procedures, Materials and methods: Between January 2005 and June 2006, we performed a retrospective evaluation of the factors thought to limit the development of this type of hospitalization. Results: The principal limiting factors were distance restrictions (respect of the 100km perimeter), the complexity of patient management for small breast tumors (several practitioners involved) and last, the non-motivating reimbursement policy. Conclusion: By changing to the Anglo-American (“one day surgery”, i.e. hospital stay less than 24hours) or hybrid system (less than 12hours+1 day surgery), ambulatory surgery could easily be offered to patients excluded by the current system (ambulatory department open less than 12hours). [Copyright &y& Elsevier]

Le cycle de l’urée permet l’excrétion d’azote issu du métabolisme des acides aminés par la conversion d’ammoniaque en urée dans le foie. Les déficits enzymatiques du cycle de l’urée (incidence cumulée : 1/8.000) se manifestent le plus souvent par une encéphalopathie liée à la toxicité cérébrale de la glutamine au niveau des astrocytes. Le diagnostic précoce d’une hyperammoniémie néonatale avec mise en place de traitements épurateurs de l’azote (hémofiltration, chélateurs) peut permettre la survie de ces enfants. Une difficulté est alors l’évaluation des séquelles de cette décompensation. En dehors des critères de gravité du coma et de l’EEG, l’IRM est mise à contribution. Il n’existe cependant que très peu de documentations neuroradiologiques notamment en période néonatale. Cas clinique: Nous rapportons ici le cas clinique d’E.-G., née à terme, qui a été admise pour un tableau digestif en réanimation à J2, évoluant rapidement vers un coma. L’ammoniémie retrouvée élevée (max. 600 μmol/l) a pu être corrigée en 48 h par hémofiltration et traitement médicamenteux. L’analyse des acides aminés plasmatiques a permis le diagnostic de déficit en argininosuccinate synthétase (citrullinémie type I), confirmée par l’étude moléculaire. L’IRM à J13 montrait des anomalies en T1 et T2 des noyaux gris centraux avec hypersignal des noyaux lenticulaires prédominant sur les régions pallidales associé à des anomalies de signal bilatérales symmétriques corticosouscorticales prédominant en régions insulaires ayant fait évoquer la possibilité d’une nécrose hémorragique. L’imagerie de contrôle réalisée à 6 mois montrait cependant une quasi disparition de ces anomalies de signal. Le développement psychomoteur de l’enfant à l’âge de 1 an est excellent. Conclusion: Alors que l’aspect des lésions en phase précoce est assez spécifique de l’atteinte neurologique par hyperammoniémie, il n’est pas forcément associé à un mauvais pronostic neurologique et peut régresser de façon quasi complète. [Copyright &y& Elsevier]

Abstract: Previous in vivo and in vitro studies have demonstrated that blood echogenicity varies under pulsatile flow, but such changes could not always be measured at physiological stroke rates. The apparent contradiction between these studies could be a result of the use of different ultrasound frequencies. Backscattered signals from porcine blood were measured in a pulsatile Couette flow apparatus. Cyclic changes in shear rate for stroke rates of 20 to 70 beats per minute (BPM) were applied to the Couette system, and different blood samples were analyzed (normal blood and blood with hyperaggregating erythrocytes promoted with dextran). To confirm that cyclic echogenicity variations were observable, spectral analysis was performed to verify if changes in echo-amplitude corresponded to the stroke rate applied to the flow. Echogenicity was measured with two single-element transducers at 10 and 35 MHz. At 35 MHz, cyclic variations in backscatter were observed from 20 to 70 BPM. However at 10 MHz, they were detected only at 20 BPM. For all cases except for hyperaggregating red blood cells (RBCs) at 20 BPM, the magnitude of the cyclic variations were higher at 35 MHz. We conclude that cyclic variations in RBC aggregation exist at physiological stroke rates, unlike what has been demonstrated in previous in-vitro studies at frequencies of 10 MHz. The increased sensitivity at 35 MHz to small changes in aggregate size might be the explanation for the better characterization of RBC aggregation at high stroke rates. Our results corroborate in-vivo observations of cyclic blood echogenicity variations in patients using a 30-MHz intravascular ultrasound catheter. (E-mail: guy.cloutier@umontreal.ca) [Copyright &y& Elsevier]

Reconstitution of the geometry of sedimentary basins is fundamental to understand the nature of present sedimentary rocks and the economic potential in hydrocarbon and mineral resources. Present-day topography of southern France shows elevations growing between the Meso-Cenozoic Aquitaine Basin to the South-East Basin across the Variscan domain and the Jurassic Causses small basin with maximum relief in the Cévennes area. Present-day elevation offset is of approximately 1000 m. This geometry questions the paleogeography and dynamics of these various domains and the relative elevation of the Variscan domain during the subsidence of adjacent Aquitaine and South-East Basins. In this study, we investigate the geological history of the Variscan basement high and the Causses small basin using paleotemperatures deduced from organic matter analysis, low temperature thermochronology and regional geological constraints. Lower Jurassic (upper Pliensbachian and Toarcian) marls sampled across the area from the Aquitaine Basin to the South-East Basin have similar depositional environments containing mainly type III oganic matter, and close Tmax values ranging between 430 and 440 ± 2 °C. These data show that the entire south Massif Central has undergone a similar burial history. considering that these values are explained by burial. Low temperature thermochronology data have been acquired on basement rocks outcropping on the borders of sedimentary basins (Rouergue, Cévennes and Margeride). Fission-track ages are ranging between 74 ± 5 and 187 ± 6 Ma and track lengths between 11.5 ± 0.3 and 13.6 ± 0.1 μm; apatite (U–Th)/He corrected ages are ranging between 65 ± 5 and 184 ± 15 Ma. Data inversion with the software QTQt indicates a cooling episode starting at the end of Early Cretaceous or beginning of Late Cretaceous from maximum temperature of 100 ± 10 °C in the Rouergue and Cévennes area and from 80 ± 10 °C in most of the Margeride area. Thermal indicators are compatible with the erosion of a Middle/Upper Jurassic and Cretaceous sedimentary cover of 1400 ± 400 m assuming a thermal paleogradient of 35 °C/km. The preserved sedimentary cover attests of a Middle and Upper Jurassic – Lower Cretaceous sedimentary cover of 1000–2000m in the Aquitaine and South-East basins. This erosion phase occurred during mid-Cretaceous and is associated to a major geodynamical event characterized by large amplitude (from the Aquitaine Basin to Durancian doming in the South-East Basin) and by kilometric offset. We interpret also these data to show that marine connections have existed between the Aquitaine Basin and the South-East Basin during the Jurassic and likely Early Cretaceous. The present-day morphology of the area has then been acquired after Cretaceous times and may result from the Pyrenean orogenic event during Eocene times. • Organic matter evolution and low temperature thermochronology show high paleotemperatures for samples from southern France. • Present-day borders of the Aquitaine and South-East basins correspond to erosion limit. • A former Jurassic and Lower Cretaceous sedimentary cover has to be considered for a large area of southern France. • Erosion occurred at the end of Early Cretaceous during a major intracontinental reorganization. [ABSTRACT FROM AUTHOR]