194 resultados para Continuum removal technique


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OBJECTIVES: We report a new salvage technique for treating venous aneurysms (VAs) complicating vascular access arteriovenous fistula (AVF) using externally reinforced venous aneurysmorrhaphy. DESIGN: A retrospective study over a 20-month period from a single centre. PATIENTS: Patients presenting to the vascular surgery department, Bordeaux University Hospital for revision of a vascular access AVF were included. METHODS: Reinforced venous aneurysmorrhaphy consisted in removal of redundant vessel wall followed by reinforcement using an external prosthetic graft. Patency, diameter and flow were assessed by duplex ultrasound at 1, 6 and 12 months after salvage. RESULTS: Thirty-eight eligible patients were identified. Five were excluded because VA was associated with central vein stenosis; the remaining 33 underwent salvage. Indications were rapidly expanding or painful VA in seven cases; VA with frequent bleeding or damaged overlying skin in eight; VA in close relation to a stenosis in two; and VA associated with high-flow rate in 16. Cannulation was attempted after 30 days. Mean follow-up time was 12 S.D. 5 months (range: 4-22). Two repaired AVFs failed. Primary 1-year patency was 93%. No aneurysm or infection occurred. Reduction of high flow was successful in 12 of 16 patients. The remaining four required re-operation. CONCLUSIONS: Reinforced venous aneurysmorrhaphy is effective in controlling venous dilation and achieving patency. Reduction of high-flow rates was not always achieved. Further study is needed to evaluate long-term efficacy of this treatment.

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Background and objective: Asthma is one of the most frequent chronic diseases affecting children and adolescents. Good compliance is indispensable for effective treatment since a suboptimal use of inhalation devices can result in decreased therapeutic efficacy and increased morbidity. The objective of this work was to evaluate the inhalation technique of paediatric patients visiting a specialized consultation clinic of a university hospital. Design: Observational prospective study during a 3-month period. Setting Specialized consultation clinic of a university hospital. Main outcome measures: This study involved 40 outpatient infants, children and adolescents visiting alone or with their parent(s). Patients' data (age, sex, weight, diagnostic, reason for consulting, previous consultations) and their medicines were compiled using an ad hoc form. Filmed sequences of the inhalation procedure used by each child were reviewed independently by members of an interdisciplinary team consisting in a physician, a pharmacist, a nurse and a physiotherapist. A score of 1 was assigned to each correct step in the procedure, and a score of 0 to an incorrect step. A perfect procedure implied 12 correct steps. Results: Thirty patients were treated with a metered-dose inhaler and an inhalation chamber (Babyhaler or AeroChamber Plus); ten other patients were treated with a dry powder inhaler (Diskus or Turbuhaler). The agreement between the members of the interdisciplinary team was considered satisfactory. Nine patients (22.5%) reached an average score lower than 7, 18 patients (45%) a score between 7 and 10 and 13 (32.5%) a score equal to or better than 10. No patient reached the maximum score of 12. Users of the metered-dose inhalers (average score = 9.2) showed a better technique than users of the dry powder inhalers (average score = 7.4). Disappointingly, the score was not improved during a second consultation or following regular consultations. Conclusions: Video recording is a simple method to evaluate the degree of mastery of an inhalation procedure in paediatric patients. The method allows a convenient and efficient identification of suboptimal procedure steps by the hospital staff, and opens the way to patient-specific teaching. In two-thirds of juvenile patients, their inhalation technique was suboptimal despite initial training. This study shows conclusively that the inhalation technique in paediatric patients must be monitored during each examination, and teaching measures taken to improve it when necessary.

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Objectifs: Evaluer la technique de reconstruction itérative VEO en tomodensitométrie (TDM) du thorax chez l'enfant. Matériels et méthodes: Etude prospective, basée sur 20 patients (7-18 ans), suivis pour mucoviscidose et adressés pour TDM de suivi. Dix patients (groupe A) ont eu une acquisition basse-dose habituelle (BD). Dix patients (groupe B) ont eu une acquisition très-basse-dose (TBD) et ultra-basse-dose (UBD). Les acquisitions BD étaient reconstruites par rétroprojection filtrée (RPF), les acquisitions TBD et UBD étaient reconstruites par RPF et VEO. L'évaluation de VEO était basée sur la réduction de dose et la qualité des images (mesures de bruit et scores de visualisation des structures pulmonaires). Résultats: Une réduction de dose d'environ 50% était obtenue dans le groupe B. La réduction du bruit en VEO par rapport aux RPF était de 55% en TBD et de 75% en UBD. En VEO, une amélioration des scores de visualisation des structures pulmonaires était obtenue en TBD et UBD. Cependant, en VEO-UBD, la visualisation des structures distales demeuraient parfois insuffisante et celle des structures proximales était altérée par une modification de texture de l'image. Conclusion: Malgré une altération possible de la texture de l'image en UBD, la technique de reconstruction VEO est performante en réduction de dose et amélioration des images.

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Current 2D black blood coronary vessel wall imaging suffers from a relatively limited coverage of the coronary artery tree. Hence, a 3D approach facilitating more extensive coverage would be desirable. The straightforward combination of a 3D-acquisition technique together with a dual inversion prepulse can decrease the effectiveness of the black blood preparation. To minimize artifacts from insufficiently suppressed blood signal of the nearby blood pools, and to reduce residual respiratory motion artifacts from the chest wall, a novel local inversion technique was implemented. The combination of a nonselective inversion prepulse with a 2D selective local inversion prepulse allowed for suppression of unwanted signal outside a user-defined region of interest. Among 10 subjects evaluated using a 3D-spiral readout, the local inversion pulse effectively suppressed signal from ventricular blood, myocardium, and chest wall tissue in all cases. The coronary vessel wall could be visualized within the entire imaging volume.

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Introduction: Roux-en-Y gastric bypass (RYGBP) is one of the commonest procedure for morbid obesity. It is associated with effective long-term weight loss, but can lead to significant complications, especially at the gastrojejunostomy (GJS) Patients and Methods: All the patients undergoing laparoscopic RYGBP at one of our two institutions were included in this study, in which we compared two different techniques for the construction of the GJS and their effects on the incidence of complications. In group A, anatomosis was performed on the posterior aspect of the gastric pouch. In group B it was performed across the staple line used to form the gastric pouch. A 21-mm circular stapler was used in all patients. Results: A total of 1128 patients were included between June 1999 and September 2009, 639 in group A and 488 in group B. Sixty patients developed a total of 65 complications at the GJS, with 14 (1,2 %) leaks, 42 (3,7 %) stricture, and 9 (0,8 %) marginal ulcers. Leaks (0,2 versus 2 %, p=0,005) and strictures (0,8 versus 5,9%, p<0,0001) were significantly fewer in group B than in group A. Conclusions: Improved surgical technique, with the GJS across the staple line used to form the gastric pouch, significantly reduces the rate of anastomotic complications at the GJS. A circular 21-mm stapler can be used with a low complication rate, and especially a low stricture rate. Additional methods to limit complications at the GJS are probably not routinely warranted.

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Chronic low back pain attributed to lumbar disc degeneration poses a serious challenge to physicians. Surgery may be indicated in selected cases following failure of appropriate conservative treatment. For decades, the only surgical option has been spinal fusion, but its results have been inconsistent. Some prospective trials show superiority over usual conservative measures while others fail to demonstrate its advantages. In an effort to improve results of fusion and to decrease the incidence of adjacent segment degeneration, total disc replacement techniques have been introduced and studied extensively. Short-term results have shown superiority over some fusion techniques. Mid-term results however tend to show that this approach yields results equivalent to those of spinal fusion. Nucleus replacement has gained some popularity initially, but evidence on its efficacy is scarce. Dynamic stabilisation, a technique involving less rigid implants than in spinal fusion and performed without the need for bone grafting, represents another surgical option. Evidence again is lacking on its superiority over other surgical strategies and conservative measures. Insertion of interspinous devices posteriorly, aiming at redistributing loads and relieving pain, has been used as an adjunct to disc removal surgery for disc herniation. To date however, there is no clear evidence on their efficacy. Minimally invasive intradiscal thermocoagulation techniques have also been tried, but evidence of their effectiveness is questioned. Surgery using novel biological solutions may be the future of discogenic pain treatment. Collaboration between clinicians and basic scientists in this multidisciplinary field will undoubtedly shape the future of treating symptomatic disc degeneration.

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Purpose:To evaluate the histological features of cellular retinal fragments on the internal limiting membrane (ILM) removed during epiretinal membrane peeling surgery with and without the aid of ICG diluted in 5% glucose Methods:ILM specimens removed from 88 eyes undergoing vitrectomy and membrane peeling surgery for idiopathic epiretinal membrane between 1995 and 2003 were reviewed retrospectively. Surgery was performed in all cases by the same surgeon using the same technique. ICG was diluted with 5% glucose. Histological analysis focused on the presence and characteristics of retinal structures on the retinal surface of the ILM. Statistical analysis compared the results between group I (conventional surgery without ICG) and group II (ICG-assisted peeling) Results:Seventy-one eyes underwent EMM surgery without the aid of ICG (group I) and seventeen underwent EMM ICG-assisted surgery assisted using ICG (group II). The amount of Muller cell debris on the retinal surface of the ILM was more significant in the group I (no ICG) than in the group II (ICG) (40.8 versus 11.8; p = 0.024). Large fragments of Muller cells were more frequently observed in the group I (no ICG) than in the group II (ICG) (63.4% versus 23.5%; p= 0.003).The presence of larger retinal elements such as neural axons and vessels were observed attached to retinal face of the ILM in 5 (7%) cases of the no-ICG group. No such retinal elements were detected in any of the histological ILM specimens of the ICG-assisted group Conclusions:The use of ICG diluted with 5% glucose in the aid of ILM removal during epiretinal membrane surgery was associated with less retinal debris attached to retinal face of the ILM compared to surgery in which ICG was not used. Our findings contradict previous reports in the literature, in which use of ICG diluted with balanced salt solution (BSS) was associated with more retinal fragments attached to the retinal face of the ILM. According to our results, we hypothesize that diluting ICG with 5% glucose may decrease the adhesion of the ILM to the underlying retinal layers such that less retinal debris is removed with peeling of the ILM.

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Abstract: The fission yeast Schizosaccharomyces pombe has proven to be an excellent model system for the study of eukaryotic cell cycle control. S. pombe cells are rod-shaped and grow mainly by elongation at their tips. They divide by the means of a centrallyplaced division septum which provides two daughter cells of equal size. S. pombe cytokinesis begins at mitotic entry, when the division site is defined by formation of the contractile acto-myosin ring (CAR). Formation of the division septum is triggered at the end of mitosis by the spindle pole body (SPB) associated septation initiation network (SIN) proteins. SIN signalling requires activation of the GTPase spg1p, whose nucleotide status is regulated by the bipartite GAP byr4pcdc16p. Removal of cdc16p from the SPB during early mitosis is thought to allow priming of the SIN by association of cdc7p with both SPBs. During anaphase cdc7p is retained on the new SPB, which also recruits the kinase sid1 p and cdc14p, while the old SP8 reassembles the byr4-cdc16p GAP and is presumed not to signal; SPB asymmetry persists throughout anaphase. The trigger for inactivation of SIN signalling at the new SPB is unknown. This study has concentrated upon cdc16p. We have undertaken the analysis of the localisation of cdc16p using time-lapse microscopy. We have observed that the localisation of cdc16p is regulated at different transitions. We have shown that cdc16p is removed from the SPB prior to the onset of spindle formation and that it reappears asymmetrically at the beginning of anaphase B. We have also demonstrated that the resetting of the SIN at the new SPB is linked to completion of CAR contraction and septum formation. We propose the existence of a mechanism that monitors cytokinesis and that couples the activity of the SI N with the presence of the CAR. During the biochemical characterization of cdc16p, We have found that it is an unstable protein and that it is subjected to polyubiquitination by the SCF and proteasomal degradation. Together, these observations help to shed new light upon the mechanisms by which cytokinesis is regulated in S. pombe. Résumé: La levure Schizosaccharomyces pombe est un excellent organisme modèle pour l'étude du cycle cellulaire eucaryote. Les cellules S. pombe ont la forme de bâtonnets et croissent par l'allongement de leurs extrémités. Elles se divisent en formant, en leur milieu une paroi cellulaire, appelé septum, permettant ainsi l'obtention de deux cellules filles de même taille. Chez S. pombe, la cytokinèse commence en début de mitose lorsque le site de division est déterminé par la formation d'un anneau d'acto-myosine. Le septum, lui, est formé uniquement en fin de mitose par la contraction de l'anneau d'actomyosine. Cette contraction est sous le contrôle d'un réseau de signalisation cellulaire appelé le «réseau d'initiation de synthèse du septum » ou « septation initiation network » (SIN), qui se situe sur les pôles du fuseau mitotique. L'activation du SIN dépend d'une GTPase appelé spg1p dont le statut nucléotidique dépend des protéines cdclóp et byr4p qui forment un complexe qui favorise l'hydrolyse du GTP en GDP. En début de mitose, cdc16p ne se situe plus sur les poles du fuseau mitotique. La GTPase spg1p se retrouve donc principalement sous sa forme couplée au GTP, ce quí va permettre son interaction avec la kinase cdc7p. Cette protéine ainsi que deux autres kinases sid2p (avec mob1p) et sid1p (avec cdc14p) permettent la transmission du signal d'initiation de la contraction de l'anneau d'acto-myosine en fin d'anaphase. Pendant l'anaphase, cdc7p, sid1 p et cdc14p localisent sur un des deux pôles du fuseau mitotique. Il en est de même pour cdc1p et by14p et le pôle contenant cdc16p et byr4p est toujours différent de celui ou les régulateurs positifs du SIN se situent. En fin de cytokinèse, cdc16 et byr4p se retrouvent à nouveau sur chaque pôle des deux cellules filles. Dans cette étude, nous nous sommes concentrés sur l'analyse de la localisation de cdc16p pendant la mitose en utilisant une technique de microscopie en temps réel. Nous avons été en mesure de déterminer que le départ de cdc16p du pole s'effectue juste avant la formation du fuseau mitotique. Nous avons aussi découvert que la localisation asymétrique des composants du SIN dépend fortement de l'entrée en anaphase B. Finalement, Nous avons montré que distribution asymétrique des composants du SIN sur les pôles du fuseau mitotique dépendait aussi fortement de !a présence de l'anneau d'acto-myosine. Ceci nous permet donc de proposer l'existence d'un mécanisme cellulaire qui permet de s'assurer que la cytokinèse est achevée avant de diminuer la signalisation du SIN. Par ailleurs, des études biochimiques nous ont permis de montrer que cdc16p est dégradé par le proteosome. Ces travaux ont permis la découverte de nouveaux modes de régulation du SIN.

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OBJECTIVES: To assess inter-observer variability of renal blood oxygenation level-dependent MRI (BOLD-MRI) using a new method of analysis, called the concentric objects (CO) technique, in comparison with the classical ROI (region of interest)-based technique. METHODS: MR imaging (3T) was performed before and after furosemide in 10 chronic kidney disease (CKD) patients (mean eGFR 43±24ml/min/1.73m(2)) and 10 healthy volunteers (eGFR 101±28ml/min1.73m(2)), and R2* maps were determined on four coronal slices. In the CO-technique, R2* values were based on a semi-automatic procedure that divided each kidney in six equal layers, whereas in the ROI-technique, all circles (ROIs) were placed manually in the cortex and medulla. The mean R2*values as assessed by two independent investigators were compared. RESULTS: With the CO-technique, inter-observer variability was 0.7%-1.9% across all layers in non-CKD, versus 1.6%-3.8% in CKD. With the ROI-technique, median variability for cortical and medullary R2* values was 3.6 and 6.8% in non-CKD, versus 4.7 and 12.5% in CKD; similar results were observed after furosemide. CONCLUSION: The CO-technique offers a new, investigator-independent, highly reproducible alternative to the ROI-based technique to estimate renal tissue oxygenation in CKD.

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A single coronary artery can complicate the surgical technique of arterial switch operations, impairing early and late outcomes. We propose a new surgical approach, successfully applied in a 2.1 kg neonate, aimed at reducing the risk of early and late compression and/or distortion of the newly constructed coronary artery system.

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Comparative analyses of survival senescence by using life tables have identified generalizations including the observation that mammals senesce faster than similar-sized birds. These generalizations have been challenged because of limitations of life-table approaches and the growing appreciation that senescence is more than an increasing probability of death. Without using life tables, we examine senescence rates in annual individual fitness using 20 individual-based data sets of terrestrial vertebrates with contrasting life histories and body size. We find that senescence is widespread in the wild and equally likely to occur in survival and reproduction. Additionally, mammals senesce faster than birds because they have a faster life history for a given body size. By allowing us to disentangle the effects of two major fitness components our methods allow an assessment of the robustness of the prevalent life-table approach. Focusing on one aspect of life history - survival or recruitment - can provide reliable information on overall senescence.

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OBJECTIVE: The aim of the current study was to investigate the biomechanical stability and fixation strength provided by a posterior approach reconstruction technique to realign the craniovertebral junction.¦METHODS: We tested seven human cadaver occipito-cervical spines (occiput-C4) by applying pure moments of ±1.5 Nm on a spine tester. Each specimen was tested in the following modes: 1) intact; 2) injured; 3) spacers alone at C1-C2 articulation (S); 4) spacers plus C1-C2 Posterior Instrumentation (S+PI); and 5) spacers plus C1-C2 posterior instrumentation plus midline wiring (S+PI+MLW). C1-C2 range of motion for each construct was obtained in flexion-extension, lateral bending, and axial rotation.¦RESULTS: In all the loading modes, S, S+PI, and S+PI+MLW constructs significantly reduced range of motion compared with the intact and injured condition (P < 0.05). There was no statistical difference between any of the three instrumentation constructs (P > 0.05).¦CONCLUSIONS: This study investigated the biomechanics of the posterior approach technique for realignment of the craniovertebral junction and also made comparisons with additional posterior fixations. The stand-alone spacers were stable in all three loading modes. Posterior instrumentation increased the stability as compared to stand-alone spacers. The third point of fixation, carried out by using midline wiring, increased the stability further. However, there was not much difference in the stability imparted with the midline wiring versus without. The present study highlights the biomechanics of this novel concept and reaffirms the view that distraction of the C1-C2 articular facets and direct articular joint atlantoaxial fixation would be an ideal method of management of basilar invagination.

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In sentinel node (SN) biopsy, an interval SN is defined as a lymph node or group of lymph nodes located between the primary melanoma and an anatomically well-defined lymph node group directly draining the skin. As shown in previous reports, these interval SNs seem to be at the same metastatic risk as are SNs in the usual, classic areas. This study aimed to review the incidence, lymphatic anatomy, and metastatic risk of interval SNs. METHODS: SN biopsy was performed at a tertiary center by a single surgical team on a cohort of 402 consecutive patients with primary melanoma. The triple technique of localization was used-that is, lymphoscintigraphy, blue dye, and gamma-probe. Otolaryngologic melanoma and mucosal melanoma were excluded from this analysis. SNs were examined by serial sectioning and immunohistochemistry. All patients with metastatic SNs were recommended to undergo a radical selective lymph node dissection. RESULTS: The primary locations of the melanomas included the trunk (188), an upper limb (67), or a lower limb (147). Overall, 97 (24.1%) of the 402 SNs were metastatic. Interval SNs were observed in 18 patients, in all but 2 of whom classic SNs were also found. The location of the primary was truncal in 11 (61%) of the 18, upper limb in 5, and lower limb in 2. One patient with a dorsal melanoma had drainage exclusively in a cervicoscapular area that was shown on removal to contain not lymph node tissue but only a blue lymph channel without tumor cells. Apart from the interval SN, 13 patients had 1 classic SN area and 3 patients 2 classic SN areas. Of the 18 patients, 2 had at least 1 metastatic interval SN and 2 had a classic SN that was metastatic; overall, 4 (22.2%) of 18 patients were node-positive. CONCLUSION: We found that 2 of 18 interval SNs were metastatic: This study showed that preoperative lymphoscintigraphy must review all known lymphatic areas in order to exclude an interval SN.

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Direct MR arthrography has a better diagnostic accuracy than MR imaging alone. However, contrast material is not always homogeneously distributed in the articular space. Lesions of cartilage surfaces or intra-articular soft tissues can thus be misdiagnosed. Concomitant application of axial traction during MR arthrography leads to articular distraction. This enables better distribution of contrast material in the joint and better delineation of intra-articular structures. Therefore, this technique improves detection of cartilage lesions. Moreover, the axial stress applied on articular structures may reveal lesions invisible on MR images without traction. Based on our clinical experience, we believe that this relatively unknown technique is promising and should be further developed.

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BACKGROUND: The present study was designed to evaluate surgeons' strategies and adherence to preventive measures against surgical site infections (SSIs). MATERIALS AND METHODS: All surgeons participating in a prospective Swiss multicentric surveillance program for SSIs received a questionnaire developed from the 2008 National (United Kingdom) Institute for Health and Clinical Excellence (NICE) clinical guidelines on prevention and treatment of SSIs. We focused on perioperative management and surgical technique in hernia surgery, cholecystectomy, appendectomy, and colon surgery (COL). RESULTS: Forty-five of 50 surgeons contacted (90%) responded. Smoking cessation and nutritional screening are regularly propagated by 1/3 and 1/2 of surgeons, respectively. Thirty-eight percent practice bowel preparation before COL. Preoperative hair removal is routinely (90%) performed in the operating room with electric clippers. About 50% administer antibiotic prophylaxis within 30 min before incision. Intra-abdominal drains are common after COL (43%). Two thirds of respondents apply nonocclusive wound dressings that are manipulated after hand disinfection (87%). Dressings are usually changed on postoperative day (POD) 2 (75%), and wounds remain undressed on POD 2-3 or 4-5 (36% each). CONCLUSIONS: Surgeons' strategies to prevent SSIs still differ widely. The adherence to the current NICE guidelines is low for many procedures regardless of the available level of evidence. Further research should provide convincing data in order to justify standardization of perioperative management.