896 resultados para BLOCK-COPOLYMER LITHOGRAPHY


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We report a case of neonatal lupus erythematosus (NLE) with congenital heart block and severe myocardial failure, which was followed from the 25th week of gestation because of fetal bradycardia. The child was delivered at the 37th week of gestation by elective cesarean section because of echocardiographically documented heart enlargement, pericardial effusion and moderate insufficiency of the mitral and tricuspid valves. In spite of immediate pacing, intubation and supportive treatment, the newborn developed progressive heart failure. Echocardiography showed endocarditis of the mitral valve and diffuse myocarditis. The heart failure resolved under steroid treatment. Our experience supports the early use of steroids in treating myocarditis due to NLE. Intrauterine steroid treatment in the presence of fetal hydrops and congenital heart block is discussed.

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Chest pain is a common presenting symptom in emergency departments, and a typical manifestation of acute myocardial infarction (AMI). Recognition of ECG changes in AMI is essential for timely diagnosis and treatment. Right bundle branch block (RBBB) may be an isolated sign of AMI, and was previously considered as a criterion for fibrinolytic therapy. Since the most recent European Society of Cardiology and American Heart Association guidelines in 2013, RBBB alone is no longer considered a diagnostic criterion of AMI, even if it occurs in the context of acute chest pain, as RBBB does not usually interfere with the interpretation of ST-segment alteration. Our case illustrates an acute septal myocardial infarction with an isolated RBBB, and thus the importance of recognising this pattern in order to permit timely diagnosis and treatment.

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INTRODUCTION: Mitral isthmus (MI) ablation is an effective option in patients undergoing ablation for persistent atrial fibrillation (AF). Achieving bidirectional conduction block across the MI is challenging, and predictors of MI ablation success remain incompletely understood. We sought to determine the impact of anatomical location of the ablation line on the efficacy of MI ablation. METHODS AND RESULTS: A total of 40 consecutive patients (87% male; 54 ± 10 years) undergoing stepwise AF ablation were included. MI ablation was performed in sinus rhythm. MI ablation was performed from the left inferior PV to either the posterior (group 1) or the anterolateral (group 2) mitral annulus depending on randomization. The length of the MI line (measured with the 3D mapping system) and the amplitude of the EGMs at 3 positions on the MI were measured in each patient. MI block was achieved in 14/19 (74%) patients in group 1 and 15/21 (71%) patients in group 2 (P = NS). Total MI radiofrequency time (18 ± 7 min vs. 17 ± 8 min; P = NS) was similar between groups. Patients with incomplete MI block had a longer MI length (34 ± 6 mm vs. 24 ± 5 mm; P < 0.001), a higher bipolar voltage along the MI (1.75 ± 0.74 mV vs. 1.05 ± 0.69 mV; P < 0.01), and a longer history of continuous AF (19 ± 17 months vs. 10 ± 10 months; P < 0.05). In multivariate analysis, decreased length of the MI was an independent predictor of successful MI block (OR 1.5; 95% CI 1.1-2.1; P < 0.05). CONCLUSIONS: Increased length but not anatomical location of the MI predicts failure to achieve bidirectional MI block during ablation of persistent AF.

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Objectives: The purpose of this study is to determine the possible differences in deflection between two needles of same length and external gauge but with different internal gauges during truncal block of the inferior alveolar nerve. The initial working hypothesis was that greater deflection may be expected with larger internal gauge needles. Study design: Four clinicians subjected 346 patients to inferior alveolar nerve block and infiltrating anesthesia of the buccal nerve trajectory for the surgical or conventional extraction of the lower third molar. A nonautoaspirating syringe system with 2 types of needle was used: a standard 27-gauge x 35-mm needle with an internal gauge of 0.215 mm or an XL Monoprotect® 27-gauge x 35-mm needle with an internal gauge of 0.265 mm. The following information was systematically recorded for each patient: needle type, gender, anesthetic technique (direct or indirect truncal block) and the number of bone contacts during the procedure, the patient-extraction side, the practitioner performing the technique, and blood aspiration (either positive or negative). Results: 346 needles were used in total. 190 were standard needles (27-gauge x 35-mm needle with an internal gauge of 0.215 mm) and 156 were XL Monoprotect®. Incidence of deflection was observed in 49.1% of cases (170 needles) where 94 were standard needles and 76 XL Monoprotect®. Needle torsion ranged from 0º and 6º. Conclusions: No significant differences were recorded in terms of deflection and internal gauge, operator, patient-extraction side, the anesthetic technique involved and the number of bone contacts during the procedure

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Newly generated olfactory receptor axons grow from the peripheral to the central nervous system aided by olfactory ensheathing cells (OECs). Thus, OEC transplantation has emerged as a promising therapy for spinal cord injuries and for other neural diseases. However, these cells do not present a uniform population, but, instead, a functionally heterogeneous population that exhibits a variety of responses including adhesion, repulsion and crossover during cell-cell and cell-matrix interactions. Some studies report that the migratory properties of OECs are compromised by inhibitory molecules and potentiated by chemical gradients. Here, we demonstrated that rodent OECs express all the components of the Nogo Receptor complex and that their migration is blocked by Myelin. Next, we used cell tracking and traction force microscopy to analyze OEC migration and its mechanical properties over Myelin. Our data relate the absence of traction force of OEC with lower migratory capacity, which correlates with changes in the F-Actin cytoskeleton and focal adhesion distribution. Lastly, OEC traction force and migratory capacity is enhanced after cell incubation with the Nogo Receptor inhibitor NEP1-40.

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Differences in parasite transmission intensity influence the process of acquisition of host immunity to Plasmodium falciparum malaria and ultimately, the rate of malaria related morbidity and mortality. Potential vaccines being designed to complement current intervention efforts therefore need to be evaluated against different malaria endemicity backgrounds. The associations between antibody responses to the chimeric merozoite surface protein 1 block 2 hybrid (MSP1 hybrid), glutamate-rich protein region 2 (GLURP R2) and the peptide AS202.11, and the risk of malaria were assessed in children living in malaria hyperendemic (Burkina Faso, n = 354) and hypo-endemic (Ghana, n = 209) areas. Using the same reagent lots and standardized protocols for both study sites, immunoglobulin (Ig) M, IgG and IgG sub-class levels to each antigen were measured by ELISA in plasma from the children (aged 6-72 months). Associations between antibody levels and risk of malaria were assessed using Cox regression models adjusting for covariates. There was a significant association between GLURP R2 IgG3 and reduced risk of malaria after adjusting age of children in both the Burkinabe (hazard ratio 0.82; 95 % CI 0.74-0.91, p < 0.0001) and the Ghanaian (HR 0.48; 95 % CI 0.25-0.91, p = 0.02) cohorts. MSP1 hybrid IgM was associated (HR 0.85; 95 % CI 0.73-0.98, p = 0.02) with reduced risk of malaria in Burkina Faso cohort while IgG against AS202.11 in the Ghanaian children was associated with increased risk of malaria (HR 1.29; 95 % CI 1.01-1.65, p = 0.04). These findings support further development of GLURP R2 and MSP1 block 2 hybrid, perhaps as a fusion vaccine antigen targeting malaria blood stage that can be deployed in areas of varying transmission intensity.

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BACKGROUND: Hemidiaphragmatic paresis after ultrasound-guided interscalene brachial plexus block is reported to occur in up to 100% of patients. We tested the hypothesis that an injection lateral to the brachial plexus sheath reduces the incidence of hemidiaphragmatic paresis compared with a conventional intrafascial injection, while providing similar analgesia. METHODS: Forty ASA I-III patients undergoing elective shoulder and clavicle surgery under general anaesthesia were randomized to receive an ultrasound-guided interscalene brachial plexus block for analgesia, using 20 ml bupivacaine 0.5% with epinephrine 1:200 000 injected either between C5 and C6 within the interscalene groove (conventional intrafascial injection), or 4 mm lateral to the brachial plexus sheath (extrafascial injection). The primary outcome was incidence of hemidiaphragmatic paresis (diaphragmatic excursion reduction >75%), measured by M-mode ultrasonography, before and 30 min after the procedure. Secondary outcomes were forced vital capacity, forced expiratory volume in 1 s, and peak expiratory flow. Additional outcomes included time to first opioid request and pain scores at 24 h postoperatively (numeric rating scale, 0-10). RESULTS: The incidences of hemidiaphragmatic paresis were 90% (95% CI: 68-99%) and 21% (95% CI: 6-46%) in the conventional and extrafascial injection groups, respectively (P<0.0001). Other respiratory outcomes were significantly better preserved in the extrafascial injection group. The mean time to first opioid request was similar between groups (conventional: 802 min [95% CI: 620-984 min]; extrafascial: 973 min [95% CI: 791-1155 min]; P=0.19) as were pain scores at 24 h postoperatively (conventional: 1.6 [95% CI: 0.9-2.2]; extrafascial: 1.6 [95% CI: 0.8-2.4]; P=0.97). CONCLUSIONS: Ultrasound-guided interscalene brachial plexus block with an extrafascial injection reduces the incidence of hemidiaphragmatic paresis and impact on respiratory function while providing similar analgesia, when compared with a conventional injection. CLINICAL TRIAL REGISTRATION: NCT02074397.

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Objective: To analyze anatomical variations associated with celiac plexus complex by means of computed tomography simulation, assessing the risk for organ injury as the transcrural technique is utilized. Materials and Methods: One hundred eight transaxial computed tomography images of abdomen were analyzed. The aortic-vertebral, celiac trunk (CeT)-vertebral, CeT-aortic and celiac-aortic-vertebral topographical relationships were recorded. Two needle insertion pathways were drawn on each of the images, at right and left, 9 cm and 4.5 cm away from the midline. Transfixed vital organs and gender-related associations were recorded. Results: Aortic-vertebral - 45.37% at left and 54.62% in the middle; CeT-vertebral - T12, 36.11%; T12-L1, 32.4%; L1, 27.77%; T11-T12, 2.77%; CeT-aortic - 53.7% at left and 46.3% in the middle; celiac-aortic-vertebral - L-l, 22.22%; M-m, 23.15%; L-m, 31.48%; M-l, 23.15%. Neither correspondence on the right side nor significant gender-related associations were observed. Conclusion: Considering the wide range of abdominal anatomical variations and the characteristics of needle insertion pathways, celiac plexus block should not be standardized. Imaging should be performed prior to the procedure in order to reduce the risks for injuries or for negative outcomes to patients. Gender-related anatomical variations involved in celiac plexus block should be more deeply investigated, since few studies have addressed the subject.

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Introduction : Le bloc transverse de l'abdomen (bloc TAP, Transversus Abdominis Plane) échoguidé consiste en l'injection d'anesthésique local dans la paroi abdominale entre les muscles oblique interne et transverse de l'abdomen sous contrôle échographique. Ceci permet de bloquer l'innervation sensitive de la paroi antérolatérale de l'abdomen afin de soulager la douleur après des interventions chirurgicales. Auparavant, cette procédure reposait sur une technique dite « à l'aveugle » qui utilisait des repères anatomiques de surface. Depuis quelques années, cette technique est effectuée sous guidage échographique ; ainsi, il est possible de visualiser les structures anatomiques, l'aiguille et l'anesthésique local permettant ainsi une injection précise de l'anesthésique local à l'endroit désiré. Les précédentes méta- analyses sur le bloc TAP n'ont inclus qu'un nombre limité d'articles et n'ont pas examiné l'effet analgésique spécifique de la technique échoguidée. L'objectif de cette méta-analyse est donc de définir l'efficacité analgésique propre du bloc TAP échoguidé après des interventions abdominales chez une population adulte. Méthode : Cette méta-analyse a été effectuée selon les recommandations PRISMA. Une recherche a été effectuée dans les bases de donnée MEDLINE, Cochrane Central Register of Controlled Clinical Trials, Excerpta Medica database (EMBASE) et Cumulative Index to Nursing and Allied Health Literature (CINAHL). Le critère de jugement principal est la consommation intraveineuse de morphine cumulée à 6 h postopératoires, analysée selon le type de chirurgie (laparotomie, laparoscopie, césarienne), la technique anesthésique (anesthésie générale, anesthésie spinale avec/ou sans morphine intrathécale), le moment de l'injection (début ou fin de l'intervention), et la présence ou non d'une analgésie multimodale. Les critères de jugement secondaires sont, entre autres, les scores de douleur au repos et à l'effort à 6 h postopératoires (échelle analogique de 0 à 100), la présence ou non de nausées et vomissements postopératoires, la présence ou non de prurit, et le taux de complications de la technique. Résultats : Trente et une études randomisées contrôlées, incluant un total de 1611 adultes ont été incluses. Indépendamment du type de chirurgie, le bloc TAP échoguidé réduit la consommation de morphine à 6 h postopératoires (différence moyenne : 6 mg ; 95%IC : -7, -4 mg ; I =94% ; p<0.00001), sauf si les patients sont au bénéfice d'une anesthésie spinale avec morphine intrathécale. Le degré de réduction de consommation de morphine n'est pas influencé par le moment de l'injection (I2=0% ; p=0.72) ou la présence d'une analgésie multimodale (I2=73% ; p=0.05). Les scores de douleurs au repos et à l'effort à 6h postopératoire sont également réduits (différence moyenne au repos : -10 ; 95%IC : -15, -5 ; I =92% ; p=0.0002; différence moyenne en mouvement : -9 ; 95%IC : -14, -5 ; I2=58% ; p<0. 00001). Aucune différence n'a été retrouvée au niveau des nausées et vomissements postopératoires et du prurit. Deux complications mineures ont été identifiées (1 hématome, 1 réaction anaphylactoïde sur 1028 patients). Conclusions : Le bloc TAP échoguidé procure une analgésie postopératoire mineure et ne présente aucun bénéfice chez les patients ayant reçu de la morphine intrathécale. L'effet analgésique mineure est indépendant du moment de l'injection ou de la présence ou non d'une analgésie multimodale.

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In this work, it was studied the behavior of the nonionic surfactant aqueous solutions, containing or not a hydrotropic agent, by resonance magnetic nuclear (NMR). We have studied monofunctional diblock copolymers of poly(propylene oxide-ethylene oxide) (R-PPO-PEO-OH, where R length is linear C4) as nonionic surfactant and sodium p-toluenesulfonate (NaPTS) as hydrotropic agent. The critical micelle concentration (CMC) of the aqueous copolymer solution was obtained from ¹H-NMR. The preliminary study of the interaction between the copolymer, under the unimer and micelle forms, and the hydrotrope, in aqueous solutions, was evaluated by ¹H-NMR and 13C-NMR.

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A simple and effective route has been developed for the synthesis of bimodal (3.6 and 9.4 nm) mesoporous silica materials that have two ordered interconnected pore networks. Mesostructures have been prepared through the self assembly mechanism by using a mixture of polyoxyethylene fluoroalkyl ether and triblock copolymer as building block. The investigation of the RF8(EO)9/P123/water phase diagram evidences that in the considered surfactant range of concentrations, the system is micellar (L1). DLS measurements indicate that this micellar phase is composed of two types of micelles, the size of the first one at around 7.6 nm corresponds unambiguously to the pure fluorinated micelles. The second type of micelles at higher diameter consists of fluorinated micelles which have accommodated a weak fraction of P123 molecules. Thus, in this study the bimodal mesoporous silica are really templated by two kinds of micelles.

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In wireless communications the transmitted signals may be affected by noise. The receiver must decode the received message, which can be mathematically modelled as a search for the closest lattice point to a given vector. This problem is known to be NP-hard in general, but for communications applications there exist algorithms that, for a certain range of system parameters, offer polynomial expected complexity. The purpose of the thesis is to study the sphere decoding algorithm introduced in the article On Maximum-Likelihood Detection and the Search for the Closest Lattice Point, which was published by M.O. Damen, H. El Gamal and G. Caire in 2003. We concentrate especially on its computational complexity when used in space–time coding. Computer simulations are used to study how different system parameters affect the computational complexity of the algorithm. The aim is to find ways to improve the algorithm from the complexity point of view. The main contribution of the thesis is the construction of two new modifications to the sphere decoding algorithm, which are shown to perform faster than the original algorithm within a range of system parameters.