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OBJECTIVE: To describe the surgical technique for removal of hoof wall masses in horses under standing sedation (SS) and local anesthesia (LA), and to report complications and long-term outcome following surgery. STUDY DESIGN: Observational retrospective study. ANIMALS: Client-owned horses (n = 30). METHODS: Horses undergoing keratoma removal under SS and LA in a single equine hospital between August 2016 and July 2023 were included in the study. Signalment, affected foot, history of lameness and/or foot abscesses, degree of lameness on admission, imaging findings (radiography and magnetic resonance imaging [MRI] when available), location of the mass, surgical technique, remedial farriery, postoperative care, complications and outcome were recorded. Long-term follow-up information was obtained by telephone questionnaire. RESULTS: A total of 30 horses met the inclusion criteria. Duration of lameness ranged from 1 to 289 days (mean 90 days). The degree of lameness varied from absent to grade 4/5 (AAEP) (mean grade 3/5). All horses underwent preoperative radiographic examination and 14/30 underwent MRI. All horses underwent partial hoof wall resection. The surgery was performed safely in all cases. Postoperative complications included marked lameness in the early postoperative period in 3/30 horses and exuberant granulation tissue formation in 2/30 horses. Long-term (>6 months) follow-up information was available for 28 horses, and 26/28 horses returned to previous levels of exercise. Recurrence was suspected in 1/30 horses. CONCLUSIONS: The complication rate was lower than previously reported for keratoma removal under general anesthesia (GA). CLINICAL SIGNIFICANCE: Removal of hoof wall masses under SS and LA can be considered as an alternative to removal under GA.
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A hallmark of unconventional superconductors is a complex electronic phase diagram where intertwined orders of charge-spin-lattice degrees of freedom compete and coexist. While the kagome metals such as CsV3Sb5 also exhibit complex behavior, involving coexisting charge density wave order and superconductivity, much is unclear about the microscopic origin of the superconducting pairing. We study the vortex lattice in the superconducting state of Cs(V0.86Ta0.14)3Sb5, where the Ta-doping suppresses charge order and enhances superconductivity. Using small-angle neutron scattering, a strictly bulk probe, we show that the vortex lattice exhibits a strikingly conventional behavior. This includes a triangular symmetry with a period consistent with 2e-pairing, a field dependent scattering intensity that follows a London model, and a temperature dependence consistent with a uniform superconducting gap. Our results suggest that optimal bulk superconductivity in Cs(V1-xTax)3Sb5 arises from a conventional Bardeen-Cooper-Schrieffer electron-lattice coupling, different from spin fluctuation mediated unconventional copper- and iron-based superconductors.
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Background: The use of antifoaming and mucolytic agents prior to upper gastrointestinal (GI) endoscopy and a thorough systematic review are essential to optimize lesion detection. This study evaluated the effect of simethicone and N-acetylcysteine on the adequate mucosal visibility (AMV) of the upper GI tract by an innovative systematic method. Methods: This randomized, double-blind controlled trial included consecutive patients who underwent diagnostic upper GI endoscopy for screening for early neoplasms between August 2019 and December 2019. The upper GI tract was systematically assessed by systematic alphanumeric-coded endoscopy. Patients were divided into 4 groups: 1) water; 2) only simethicone; 3) N-acetylcysteine + simethicone; and 4) only N-acetylcysteine. The following parameters were assessed in each group: age, sex, body mass index, level of adequate mucosal visibility, and side-effects. Results: A total of 4564 images from upper GI areas were obtained for evaluation. The mean AMV in the 4 groups was 93.98±7.36%. The N-acetylcysteine + simethicone group had a higher cleaning percentage compared with the other groups (P=0.001). There was no significant difference among the remaining groups, but several areas had better cleaning when a mucolytic or antifoam alone was used. No side-effects were found in any group. Conclusion: The combination of N-acetylcysteine plus simethicone optimizes the visibility of the mucosa of the upper GI tract, which could potentially increase diagnostic yield.
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BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) typically presents with gait disturbances, cognitive decline, and urinary incontinence. Symptomatic improvement generally occurs following shunt placement, but limited evidence exists on the quality of life (QOL) metrics in iNPH. Therefore, we conducted a prospective study of the effect of shunt placement on QOL in iNPH patients, using Quality of Life in Neurologic Disorders (Neuro-QOL) metrics. METHODS: Eligible patients underwent shunt placement after evidence of symptomatic improvement following temporary cerebrospinal fluid diversion via inpatient lumbar drain trial. Patients were administered short- and long-form Neuro-QOL assessments prior to shunt placement and at 6-month and 1-year postoperative timepoints to evaluate lower extremity mobility, cognitive function, and social roles and activities participation. Changes in QOL measures were analyzed using a repeated-measures linear mixed effects model. RESULTS: There were 48 patients with a mean age of 75.4 ± 6.3 years. Average short-form mobility scores improved by 3.9 points (14.6%) at 6-month follow-up and by 6.2 points (23.2%) at 1-year follow-up compared with preoperative baseline (P = 0.027 and P = 0.0002, respectively). Short-form cognition scores increased by 5.2 points (22.4%) at 6 months and 10.9 points (47.0%) at 1 year postoperatively (P = 0.007 and P < 0.0001, respectively). On long-form assessment, social roles and activity participation scores improved by 29.3 points (23.4%) at 6 months and 31.6 points (25.2%) at 1 year after surgery compared to baseline (P = 0.028 and P = 0.02, respectively). CONCLUSIONS: Our findings demonstrate that shunt placement leads to improved QOL in iNPH patients across multiple domains. Significant improvements in mobility, cognition, and social roles and activity participation are realized within the first 6 months and are sustained on 1-year follow-up.
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In helimagnetic metals, ac current-driven spin motions can generate emergent electric fields acting on conduction electrons, leading to emergent electromagnetic induction (EEMI). Recent experiments reveal the EEMI signal generally shows a strongly current-nonlinear response. In this study, we investigate the EEMI of Tb5Sb3, a short-period helimagnet. Using small angle neutron scattering we show that Tb5Sb3 hosts highly disordered helimagnetism with a distribution of spin-helix periodicity. The current-nonlinear dynamics of the disordered spin helix in Tb5Sb3 indeed shows up as the nonlinear electrical resistivity (real part of ac resistivity), and even more clearly as a nonlinear and huge EEMI (imaginary part of ac resistivity) response. The magnitude of the EEMI reaches as large as several tens of µH for Tb5Sb3 devices on the scale of several tens of µm, originating to noncollinear spin textures possibly even without long-range helimagnetic order.
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Van-der-Waals magnetic materials can be exfoliated to realize ultrathin sheets or interfaces with highly controllable optical or spintronics responses. In majority, these are collinear ferro-, ferri-, or antiferromagnets, with a particular scarcity of lattice-incommensurate helimagnets of defined left- or right-handed rotation sense, or helicity. Here, we report polarized neutron scattering experiments on DyTe3, whose layered structure has highly metallic tellurium layers separated by double-slabs of dysprosium square nets. We reveal cycloidal (conical) magnetic textures, with coupled commensurate and incommensurate order parameters, and probe the evolution of this ground state in a magnetic field. The observations are well explained by a one-dimensional spin model, with an off-diagonal on-site term that is spatially modulated by DyTe3's unconventional charge density wave (CDW) order. The CDW-driven term couples to antiferromagnetism, or to the net magnetization in an applied magnetic field, and creates a complex magnetic phase diagram indicative of competing interactions in this easily cleavable van-der-Waals helimagnet.
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INTRODUCTION: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease, characterized by painful and recurrent lesions in apocrine gland-bearing skin areas. It is a heterogeneous disease, which makes assessment and data collection difficult. Questionnaires with detailed items, such as the Belgian European Registry for Hidradenitis Suppurativa (ERHS-Be), are useful to study HS and its associated comorbidities. The aim of this registry was to uncover new factors associated with HS and understand HS patients' clinical profiles and efficacy of treatments. MATERIAL AND METHODS: The ERHS-Be registry is based on questionnaires, with sections for sociodemographic data, medical and HS history, clinical examination, and treatment plan. It allows identification of different clinical phenotypes and automatic calculation of severity scores. RESULTS: At present, 606 patients are included in the ERHS-Be (67% women, 33% men). The mean age at the first visit is 38.5 years. Tobacco use is present in 72.6% of patients. A family history of HS is noted in 42% of patients. Comorbidities are documented in this cohort: depression is present in 43.8% of patients, arthritis in 27.8%, obesity in 31.5%, hypertension in 10.6%, diabetes mellitus in 6.4%, and dyslipidemia in 12.4%. Moreover, 7.7% of patients suffer from IBD and 27.4% have a pilonidal sinus. History of severe acne is found in 32.1% of patients and psoriasis in 9.3%. Thirteen percent of women in our cohort suffer from polycystic ovarian syndrome. Severity of disease is quantified in 533 patients: for instance, Hurley I, II, and III scores proportions are, respectively, 32.3%, 52.7%, and 15%, while the mean IHS4 score is 5.2. This registry also enables determination of relative phenotype proportions in our cohort, according to different classifications. CONCLUSION: The ERHS-Be questionnaires allow systematic and larger data collection, including detailed comorbidities, phenotypes, and severity of disease. Analysis of this large database will contribute to a better understanding and management of HS, at a time where new therapeutic options are becoming available.
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Hidradenitis Supurativa , Fenotipo , Sistema de Registros , Índice de Severidad de la Enfermedad , Humanos , Hidradenitis Supurativa/epidemiología , Femenino , Masculino , Adulto , Bélgica/epidemiología , Persona de Mediana Edad , Comorbilidad , Encuestas y Cuestionarios , Adulto Joven , Obesidad/epidemiologíaRESUMEN
The migration of an electron-loss center (hole) in calf thymus DNA to bisbenzimidazole ligands bound in the minor groove is followed by pulse radiolysis combined with time-resolved spectrophotometry. The initially observed absorption spectrum upon oxidation of DNA by the selenite radical is consistent with spin on cytosine (C), as the GC⢠pair neutral radical, followed by the spectra of oxidized ligands. The rate of oxidation of bound ligands increased with an increase in the ratio (r) ligands per base pair from 0.005 to 0.04. Both the rate of ligand oxidation and the estimated range of hole transfer (up to 30 DNA base pairs) decrease with the decrease in one-electron reduction potential between the GC⢠pair neutral radical of ca. 1.54 V and that of the ligand radicals (E0', 0.90-0.99 V). Linear plots of log of the rate of hole transfer versus r give a common intercept at r = 0 and a free energy change of 12.2 ± 0.3 kcal mol-1, ascribed to the GC⢠pair neutral radical undergoing a structural change, which is in competition to the observed hole transfer along DNA. The rate of hole transfer to the ligands at distance, R, from the GC⢠pair radical, k2, is described by the relationship k2 = k0 exp(constant/R), where k0 includes the rate constant for surmounting a small barrier.
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Emparejamiento Base , ADN , ADN/química , Radicales Libres/química , Oxidación-Reducción , Bencimidazoles/química , Animales , Bovinos , Ligandos , Bisbenzimidazol/química , Reparación del ADN , Daño del ADN , Citosina/químicaRESUMEN
77Se-NMR is used to characterise several chalcogen bonded complexes of derivatives of the organoselenium drug ebselen, exploring a range of electron demand. NMR titration experiments support the intuitive understanding that chalcogen bond donors bearing more electron withdrawing substituents give rise stronger chalcogen bonds. The chemical shift of the selenium nucleus is also shown to move upfield as it participates in a chalcogen bond. Solid-state NMR is used to explore chalcogen bonding in co-crystals. Due to the lack of molecular reorientation on the NMR timescale in the solid state, the shape of the chemical shift tensor can be determined using this technique. A range of co-crystals are shown to have extremely large chemical shift anisotropy, which suggests a strongly anisotropic electron density distribution around the selenium atom. A single crystal NMR experiment was conducted using one of the co-crystals, affording the absolute orientation of the chemical shift tensor within the crystal. This showed that the selenium nucleus is strongly shielded in the direction of the chalcogen bond (due to the approach of the lone pair of the Lewis base), and strongly deshielded in the perpendicular direction. The orientation of the deshielded axis is consistent with the presence of a second σ-hole which is not participating in a chalcogen bond, showing the profound effect of electron density anisotropy on the chemical shift.
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We report investigations of the magnetic textures in periodic multilayers [Pt(1 nm)/(CoFeB(0.8 nm)/Ru(1.4 nm)]10 using polarised neutron reflectometry (PNR) and small-angle neutron scattering (SANS). The multilayers are known to host skyrmions stabilized by Dzyaloshinskii-Moriya interactions induced by broken inversion symmetry and spin-orbit coupling at the asymmetric interfaces. From depth-dependent PNR measurements, we observed well-defined structural features and obtained the layer-resolved magnetization profiles. The in-plane magnetization of the CoFeB layers calculated from fitting of the PNR profiles is found to be in excellent agreement with magnetometry data. Using SANS as a bulk probe of the entire multilayer, we observe long-period magnetic stripe domains and skyrmion ensembles with full orientational disorder at room temperature. No sign of skyrmions is found below 250 K, which we suggest is due to an increase of an effective magnetic anisotropy in the CoFeB layer on cooling that suppresses skyrmion stability. Using polarised SANS at room temperature, we prove the existence of pure Néel-type windings in both stripe domain and skyrmion regimes. No Bloch-type winding admixture, i.e. an indication for hybrid windings, is detected within the measurement sensitivity, in good agreement with expectations according to our micromagnetic modelling of the multilayers. Our findings using neutron techniques provide valuable microscopic insights into the rich magnetic behavior of skyrmion-hosting multilayers, which are essential for the advancement of future skyrmion-based spintronic devices.
The study presents a unique investigation of [Pt/CoFeB/Ru]10 multilayers, revealing suppressed skyrmion phases, intricate magnetic domain structures, and Néel-type domain walls, providing crucial insights for spintronic applications.
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Objective: Screening is an effective tool for detecting colorectal lesions in asymptomatic subjects. There is a positive correlation between fecal immunochemical test (FIT) values and the size of tumors. Despite the efficacy of screening, the detection of colorectal cancer (CRC) remains low. The primary objective was to evaluate the best FIT cutoff value for detecting advanced adenomas and CRC among individuals at average risk in a country with a high incidence and morbidity from CRC. Methods: This observational and prospective study analyzed consecutive cases in 1461 asymptomatic subjects with a positive FIT (≥ 100 ng hemoglobin [Hb]/mL) referred for colonoscopy (2012-2015) at a tertiary center in Uruguay. Results: Colorectal lesions were detected in 35.3% (516/1461) of cases, with a mean age of 62.8 ± 8.3 years. About 53.2% were men and 65.1% of the tumors were located in the left side of the colon. The size of the lesion and FIT values (p = 0.001) were positively correlated. Laterally spreading tumors predominated in the right colon (586 ng Hb/mL; 95% Confidence interval [CI] 443.4-760). One hundred and thirty-five (26%) lesions were advanced adenomas (15 ± 6.7 mm); 694.6 ng/mL; 95% CI 632.4-756.9). The highest diagnostic yield (0.5112) for advanced adenomas was at a FIT level of 400 ng Hb/mL (accuracy 88.6%). There were significant differences in FIT values early and advanced CRC (927 ng/mL; [95% CI: 637-1082] vs. 1453 [95% CI: 1352-1594; p = 0.001]). Conclusion: A FIT value of 400 ng Hb/mL was the best diagnostic yield to detect advanced adenomas and CRC. This value is useful during the COVID-19 pandemic as it allows prioritization of colonoscopy to those most at risk of significant disease, thus reducing risks to both patients and healthcare workers.
Objetivo: El cribado es una herramienta eficaz para detectar lesiones colorrectales en sujetos asintomáticos. Existe una correlación positiva entre los valores de la prueba inmunoquímica fecal (FIT) y el tamaño de los tumores. A pesar de la eficacia del cribado, la detección del cáncer colorrectal (CCR) sigue siendo baja. El objetivo principal fue evaluar el mejor valor de corte FIT para detectar adenomas avanzados y CCR entre personas con riesgo promedio en un país con alta incidencia y morbilidad por CCR. Métodos: Este estudio observacional y prospectivo analizó 1461 sujetos asintomáticos con FIT positivo (≥ 100 ng de hemoglobina [Hb]/mL) remitidos para colonoscopia (2012-2015) en un centro terciario en Uruguay. Resultados: Se detectaron lesiones colorrectales en el 35,3% (516/1461) de los casos, con una edad media de 62,8 ± 8,3 años. Alrededor del 53,2% eran hombres y el 65,1% de los tumores estaban ubicados en el lado izquierdo del colon. El tamaño de la lesión y los valores FIT (p = 0,001) se correlacionaron positivamente. Los tumores con extensión lateral predominaron en el colon derecho (586 ng Hb/mL; intervalo de confianza [IC] del 95%: 443,4-760). Ciento treinta y cinco (26%) lesiones fueron adenomas avanzados (15 ± 6,7 mm); 694,6 ng/ml; IC 95% 632,4-756,9). El rendimiento diagnóstico más alto (0,5112) para los adenomas avanzados se obtuvo con un nivel FIT de 400 ng Hb/ml (precisión del 88,6%). Hubo diferencias significativas en los valores de FIT de CCR temprano y avanzado (927 ng/mL; [IC 95%: 637-1082] vs. 1453 [IC 95%: 1352-1594; p = 0,001]). Conclusión: Un valor FIT de 400 ng Hb/mL fue el mejor rendimiento diagnóstico para detectar adenomas avanzados y CCR. Este valor es útil durante la pandemia de COVID-19, ya que permite priorizar la colonoscopia a aquellos con mayor riesgo de padecer una enfermedad importante, reduciendo así los riesgos tanto para los pacientes como para los trabajadores de la salud.
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Microthecaline A (1), the known antiplasmodial quinoline serrulatane alkaloid from the roots of Eremophila microtheca F. Muell. ex Benth. (Scrophulariaceae), was targeted for isolation and subsequent use in the generation of a semisynthetic ether library. A large-scale extraction and isolation yielded the previously undescribed quinoline serrulatane microthecaline B (2), along with crystalline 1 that enabled the first X-ray crystallographic analysis to be undertaken on this rare alkaloid structure class. The X-ray diffraction analysis of 1 supported the absolute configuration assignment of microthecaline A, which was originally assigned by ECD data analysis. Microthecaline A (1) was converted into 10 new semisynthetic ether derivatives (3-12) using a diverse series of commercially available alkyl halides. Chemical structures of the new serrulatane alkaloid and semisynthetic ether analogues were assigned by spectroscopic and spectrometric analyses. Antiplasmodial evaluations of 1-12 showed that the semisynthetic derivative 5 elicited the most potent activity with an IC50 value of 7.2 µM against Plasmodium falciparum 3D7 (drug-sensitive) strain.
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Alcaloides , Antimaláricos , Plasmodium falciparum , Antimaláricos/farmacología , Antimaláricos/química , Antimaláricos/aislamiento & purificación , Alcaloides/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Plasmodium falciparum/efectos de los fármacos , Estructura Molecular , Eremophila (Planta)/química , Cristalografía por Rayos X , Quinolinas/farmacología , Quinolinas/química , Raíces de Plantas/química , Éteres/farmacología , Éteres/químicaRESUMEN
The first total synthesis of myxobacteria metabolite icumazole A (1) is reported. Key steps in the route include an organocatalyzed asymmetric self-aldol reaction followed by an acetate aldol reaction to form the stereotriad present in the oxazole moiety, an intramolecular Diels-Alder reaction to form the isochromanone, and an acetylide addition and selective methylation. The final steps involved a high-yielding modified Cadiot-Chodkiewicz coupling and stereoselective reduction to secure the Z,Z-diene and afford 1.
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The known oxygenated polyhalogenated diphenyl ether, 2-(2',4'-dibromophenoxy)-3,5-dibromophenol (1), with previously reported activity in multiple cytotoxicity assays was isolated from the sponge Lamellodysidea sp. and proved to be an amenable scaffold for semisynthetic library generation. The phenol group of 1 was targeted to generate 12 ether analogues in low-to-excellent yields, and the new library was fully characterized by NMR, UV, and MS analyses. The chemical structures for 2, 8, and 9 were additionally determined via single-crystal X-ray diffraction analysis. All natural and semisynthetic compounds were evaluated for their ability to inhibit the growth of DU145, LNCaP, MCF-7, and MDA-MB-231 cancer cell lines. Compound 3 was shown to have near-equivalent activity compared to scaffold 1 in two in vitro assays, and the activity of the compounds with an additional benzyl ring appeared to be reliant on the presence and position of additional halogens.
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Antineoplásicos , Éter , Éteres/farmacología , Éteres de Etila , Éteres Fenílicos/farmacología , Antineoplásicos/farmacologíaRESUMEN
BACKGROUND: Left ventricular free wall rupture (LVFWR) and interventricular septal rupture (VSR) are potentially catastrophic mechanical complications after acute myocardial infarction (AMI). When they occur together, "double myocardial rupture" (DMR), survival is unlikely. DMR is seen in only 0.3% of all AMIs. With or without surgical intervention, the odds are against the patient. CASE PRESENTATION: A 57-year-old male self-referred to the emergency department of a remote hospital 5 days after first experiencing chest pain. Investigations in ED confirmed an inferior ST-segment elevation myocardial infarction (STEMI) complicated by DMR. Coronary angiography revealed a mid-course total occlusion of the right coronary artery (RCA). He was rapidly transferred to our regional cardiac surgical unit, arriving straight into the operating theatre, in cardiogenic shock. He was briefly conscious, before arresting prior to intubation and being massaged onto bypass. Not only did he survive the all-night operation, requiring a mitral valve replacement in the process, but he survived multiple postoperative complications to be eventually transferred on postoperative day 66, neurologically intact, to a peripheral unit to complete his rehabilitation. He was subsequently discharged home 88 days after the operation and was able to ambulate with a walking frame into his first postoperative follow-up clinic appointment. CONCLUSIONS: Our patient, against all odds, has survived DMR and multiple postoperative complications. We present the details of his case and the literature surrounding the condition. The patient's mental fortitude and his supportive family played a significant role, along with excellent multidisciplinary team work, in assuring his survival.
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Rotura Cardíaca Posinfarto , Rotura Cardíaca , Infarto del Miocardio , Masculino , Humanos , Persona de Mediana Edad , Rotura Cardíaca Posinfarto/cirugía , Infarto del Miocardio/cirugía , Rotura Cardíaca/cirugía , Rotura Cardíaca/complicaciones , Choque Cardiogénico/etiología , Choque Cardiogénico/cirugía , Complicaciones PosoperatoriasRESUMEN
BACKGROUND AND AIMS: Circumferential endoscopic submucosal dissection (cESD) in the esophagus has been reported to be feasible in small Eastern case series. We assessed the outcomes of cESD in the treatment of early esophageal squamous cell carcinoma (ESCC) in Western countries. METHODS: We conducted an international study at 25 referral centers in Europe and Australia using prospective databases. We included all patients with ESCC treated with cESD before November 2022. Our main outcomes were curative resection according to European guidelines and adverse events. RESULTS: A total of 171 cESDs were performed on 165 patients. En bloc and R0 resections rates were 98.2% (95% confidence interval [CI], 95.0-99.4) and 69.6% (95% CI, 62.3-76.0), respectively. Curative resection was achieved in 49.1% (95% CI, 41.7-56.6) of the lesions. The most common reason for noncurative resection was deep submucosal invasion (21.6%). The risk of stricture requiring 6 or more dilations or additional techniques (incisional therapy/stent) was high (71%), despite the use of prophylactic measures in 93% of the procedures. The rates of intraprocedural perforation, delayed bleeding, and adverse cardiorespiratory events were 4.1%, 0.6%, and 4.7%, respectively. Two patients died (1.2%) of a cESD-related adverse event. Overall and disease-free survival rates at 2 years were 91% and 79%. CONCLUSIONS: In Western referral centers, cESD for ESCC is curative in approximately half of the lesions. It can be considered a feasible treatment in selected patients. Our results suggest the need to improve patient selection and to develop more effective therapies to prevent esophageal strictures.
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Resección Endoscópica de la Mucosa , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/cirugía , Neoplasias Esofágicas/patología , Resección Endoscópica de la Mucosa/métodos , Esofagoscopía/métodos , Resultado del Tratamiento , Estudios RetrospectivosRESUMEN
In this report, a microporous metal-organic framework of [Ca(TDC)(DMA)]n (1) and a two-dimensional coordination polymer of [Ca(TDC)(DMF)2 ]n (2), (TDC2- =Thiophene-2,5-dicarboxylate, DMA=N, N'-dimethylacetamide and DMF=N, N'-dimethylformamide) based on Ca(II) were designed by the effect of solvent, and X-ray analysis was performed for the single crystals of 1 and 2. Then, compound 1 was synthesized in three different methods and identified with a set of analyses. Compared to other adsorbents, MOFs are widely used in the field of adsorption and separation of various gases due to a series of distinctive features such as diverse and adjustable structures pores with different dimensions, high porosity and surface area with regular distribution of active sites. Therefore, the ability of 1 to uptake single gases (CH4 , CO2 , C2 H2 , H2, and N2 ) and separation of several binary mixtures of gases (CO2 /CH4 , CO2 /N2 , CO2 /H2 and CO2 /C2 H2 ), were investigated using Grand Canonical Monte Carlo simulations. Volumetric and gravimetric adsorption isotherms in various operating conditions, the isosteric heat of adsorption (qst ), the chemical potential for each thermodynamic state, and snapshots during the simulation process were reported in all cases. The results obtained from the adsorption simulation indicate that compound 1 has a high capacity for uptake of H2 (16â mmol g-1 ) and N2 (12.5â mmol g-1 ), CO2 (6.6â mmol g-1 ), C2 H2 (5â mmol g-1 ) and CH4 (1.5â mmol g-1 ) gases at 1â bar. It also performs well in separating CO2 in binary mixtures, which can be attributed to the presence of open metal sites in nodes of 1 and their electrostatic tendency to interact with CO2 containing the higher quadrupole dipole moment compared to other components of the mixture.
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Atopic dermatitis (AD) is one of the most common, bothersome and difficult to treat skin disorders. Recent introduction of new systemic treatments has revolutionized the management of AD. The goal of this guideline is to provide evidence-based recommendations for the management of patients suffering from atopic dermatitis that easily can be implemented in clinical practice. These recommendations were developed by 11 Belgian AD experts. Comments of all experts on the proposed statements were gathered, followed by an online voting session. The most relevant strategies for the management and treatment of AD in the context of the Belgian health care landscape are discussed. General measures, patient education and adequate topical treatment remain the cornerstones of AD management. For moderate to severe AD, the introduction of biologics and JAK inhibitors show unprecedented efficacy, although currently access is limited to a subgroup of patients meeting the reimbursement criteria.
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Dermatitis Atópica , Humanos , Dermatitis Atópica/tratamiento farmacológico , Bélgica , Administración CutáneaRESUMEN
Magnetic skyrmions, topological vortex-like spin textures, garner significant interest due to their unique properties and potential applications in nanotechnology. While they typically form a hexagonal crystal with distinct internal magnetisation textures known as Bloch- or Néel-type, recent theories suggest the possibility for direct transitions between skyrmion crystals of different lattice structures and internal textures. To date however, experimental evidence for these potentially useful phenomena have remained scarce. Here, we discover the polar tetragonal magnet EuNiGe3 to host two hybrid skyrmion phases, each with distinct internal textures characterised by anisotropic combinations of Bloch- and Néel-type windings. Variation of the magnetic field drives a direct transition between the two phases, with the modification of the hybrid texture concomitant with a hexagonal-to-square skyrmion crystal transformation. We explain these observations with a theory that includes the key ingredients of momentum-resolved Ruderman-Kittel-Kasuya-Yosida and Dzyaloshinskii-Moriya interactions that compete at the observed low symmetry magnetic skyrmion crystal wavevectors. Our findings underscore the potential of polar magnets with rich interaction schemes as promising for discovering new topological magnetic phases.
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An approach to more highly oxidized alkyl citrates by direct regio- and stereoselective oxidations is reported. The total synthesis and structural assignment of alkyl citrate L-731-128 are described, and the synthesis of its C4 oxidized congener L-731,127 utilized a regio- and stereoselective enolate oxidation with oxygen gas. A highly stereoselective Rubottom oxidation of a cyclic silylketene acetal then enabled oxidation at C2 to afford the cinatrins C1 and C3.