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Background: Chagas cardiomyopathy (CCM) is increasingly prevalent in developed countries due to migration from endemic areas. Accurate risk stratification is crucial due to the variable clinical course of CCM., Objective: To analyze the association between Rassi score progression and electrophysiology study (EPS) changes in CCM patients., Methods: This prospective, observational cohort study involved CCM patients from two tertiary hospitals. Patients were classified as low, intermediate, or high risk based on the Rassi score. Data collected included demographics, clinical history, and diagnostic tests. EPS assessed AH, HH, and HV intervals, and inducibility of ventricular arrhythmias. Follow-ups were at 30 days and six-month intervals, with individualized discussions for cardiac implantable electric devices (CIED) based on EPS results., Results: Of 67 screened CCM patients, 59 underwent EPS. The mean Rassi score was 8.7 ± 4.5 points, with 33.8 % low, 38.9 % intermediate, and 27.1 % high risk. EPS abnormalities were found in 57.6 % of patients, mainly VT/VF (52.5 %). Most induced ventricular arrhythmias were monomorphic VT (80.7 %). A significant association was found between Rassi score risk classification and EPS changes (OR = 1.88 95 %CI: 1.15-3.06 p = 0.02). Higher Rassi scores correlated with VT presence on EPS (p = 0.0036). Syncope/pre-syncope had an OR 2.45 95 %CI:1.21-4.94; p = 0.012, independent of Rassi risk. Decreased ejection fraction was linked to EPS changes (p = 0.04)., Conclusion: EPS changes among CCM was associated with progression of the Rassi score, indicating its utility as a stratification tool. Factors such as the presence of syncope/pre-syncope, decreased LVEF and wall motion abnormalities emerged as independent predictors within Rassi scores for changes in EPS., Competing Interests: Declaration of competing interest The authors have declared that no competing interests exist related to this project., (Copyright © 2024. Published by Elsevier B.V.)

Biopolymers such as carboxymethyl cellulose and hyaluronic acid are alternative substrates for conformable organic light-emitting diodes (OLEDs). However, drawbacks such as mechanical stress susceptibility can hinder the device's performance under stretched conditions. To overcome these limitations, herein, we developed a nanocomposite based on CMC/HA (carboxymethyl cellulose/hyaluronic acid) and synthetic Laponite, intending to improve the mechanical strength without compromising the film flexibility and transparency (transmittance >80%; 380-700 nm) as substrates for conformable OLEDs. From XRD, FTIR, CP-MAS NMR, and TGA/DTG characterization techniques, it was possible to conclude the presence of Laponite randomly dispersed between the polymer chains. CMC/HA with 5% (w/w) Laponite, CMC/HA 5, presented a higher tensile strength (370.6 MPa) and comparable Young's modulus (51.0 ± 1.2 MPa) in comparison to the nanocomposites and pristine films, indicating a better candidate for the device's substrates. To produce the OLED, the multilayer structure ITO/MoO 3 /NPB/TCTA:Ir(ppy) 3 /TPBi:Ir(ppy) 3 /BPhen/LiF was deposited onto the CMC/HA 5 substrate. The OLEDs fabricated using CMC/HA 5 substrates showed higher luminance (12 kcd/m 2 ) and irradiance (0.9 mW/cm 2 ) values when compared with those based on commercial bacterial cellulose. However, the same device presented a lower efficiency (3.2 cd/A) due to a higher current density. Moreover, the OLED fabricated onto the Laponite-modified biopolymer presented reproducible behavior when submitted to continuous bending stress. Thus, CMC/HA 5 demonstrates potential as a transparent conductor substrate for biopolymer-based OLEDs with comparable performance to commercial bacterial cellulose features., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The reaction between the ( R , S )-fixolide 4-methyl-thio-semicarbazone and Pd II chloride yielded the title compound, [Pd(C 20 H 30 N 3 S) 2 ]·C 2 H 6 O {common name: trans -bis-[( R , S )-fixolide 4-methyl-thio-semicarbazonato-κ 2 N 2 S ]palladium(II) ethanol monosolvate}. The asymmetric unit of the title compound consists of one bis-thio-semicarbazonato Pd II complex and one ethanol solvent mol-ecule. The thio-semicarbazononato ligands act as metal chelators with a trans configuration in a distorted square-planar geometry. A C-H⋯S intra-molecular inter-action, with graph-set motif S (6), is observed and the coordination sphere resembles a hydrogen-bonded macrocyclic environment. Additionally, one C-H⋯Pd anagostic inter-action can be suggested. Each ligand is disordered over the aliphatic ring, which adopts a half-chair conformation, and two methyl groups [s.o.f. = 0.624 (2):0.376 (2)]. The disorder includes the chiral carbon atoms and, remarkably, one ligand has the ( R )-isomer with the highest s.o.f. value atoms, while the other one shows the opposite, the atoms with the highest s.o.f. value are associated with the ( S )-isomer. The N-N-C(=S)-N fragments of the ligands are approximately planar, with the maximum deviations from the mean plane through the selected atoms being 0.0567 (1) and -0.0307 (8) Å (r.m.s.d. = 0.0403 and 0.0269 Å) and the dihedral angle with the respective aromatic rings amount to 46.68 (5) and 50.66 (4)°. In the crystal, the complexes are linked via pairs of N-H⋯S inter-actions, with graph-set motif R 2 2 (8), into centrosymmetric dimers. The dimers are further connected by centrosymmetric pairs of ethanol mol-ecules, building mono-periodic hydrogen-bonded ribbons along [011]. The Hirshfeld surface analysis indicates that the major contributions for the crystal cohesion are [atoms with highest/lowest s.o.f.s considered separately]: H⋯H (81.6/82.0%), H⋯C/C⋯H (6.5/6.4%), H⋯N/N⋯H (5.2/5.0%) and H⋯S/S⋯H (5.0/4.9%)., (© Melo et al. 2023.)

As the development of nanotechnology progresses, organic electronics have gained momentum in recent years, and the production and rapid development of electronic devices based on organic semiconductors, such as organic light-emitting diodes (OLEDs), organic photovoltaic cells (OPVs), and organic field effect transistors (OFETs), among others, have excelled. Their uses extend to the fabrication of intelligent screens for televisions and portable devices, due to their flexibility and versatility. Lately, great efforts have been reported in the literature to use them in the biomedical field, such as in photodynamic therapy. In tandem, there has been considerable interest in the design of advanced materials originating from natural sources. Bacterial nanocellulose (BNC) is a natural polymer synthesized by many microorganisms, notably by non-pathogenic strains of Komagataeibacter ( K. xylinus , K. hansenii , and K. rhaeticus ). BNC shows distinct physical and mechanical properties, including its insolubility, rapid biodegradability, tensile strength, elasticity, durability, and nontoxic and nonallergenic features, which make BNC ideal for many areas, including active and intelligent food packaging, sensors, water remediation, drug delivery, wound healing, and as conformable/flexible substrates for application in organic electronics. Here, we review BNC production methods, properties, and applications, focusing on electronic devices, especially OLEDs and flexible OLEDs (FOLEDs). Furthermore, we discuss the future progress of BNC-based flexible substrate nanocomposites.

Carotenoids over-producing yeast has become a focus of interest of the biorefineries, in which the integration of the bioproduction with the following downstream processing units for the recovery and purification of carotenoids and other value-added byproducts is crucial to improve the sustainability and profitability of the overall bioprocess. Aiming the future implementation of Phaffia rhodozyma-based biorefineries, in this work, an integrative process for fractionation of intracellular compounds from P. rhodozyma biomass using non-hazardous bio-based solvents was developed. After one-extraction step, the total amount of astaxanthin, β-carotene, lipids and proteins recovered was 63.11 µg/g DCW , 42.81 µg/g DCW , 53.75 mg/g DCW and 10.93 mg/g, respectively. The implementation of sequential back-extraction processes and integration with saponification and precipitation operations allowed the efficient fractionation and recovery (% w/w) of astaxanthin (∼72.5 %), β-carotene ∼90.17 %), proteins (21.04 %) and lipids (23.72 %). After fractionation, the manufacture of carotenoids-based products was demonstrated, through the mixture of carotenoids-rich extracts with bacterial cellulose to obtain biologically active bioplastics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Scaffolds of metal-based compounds can act as pharmacophore groups in several ligands to treat various diseases, including tropical infectious diseases (TID). In this review article, we investigate the contribution of these moieties to medicinal inorganic chemistry in the last seven years against TID, including American trypanosomiasis (Chagas disease), human African trypanosomiasis (HAT, sleeping sickness), leishmania, and malaria. The most potent metal-based complexes are displayed and highlighted in figures, tables and graphics; according to their pharmacological activities (IC 50 > 10μM) against Trypanosomatids and Plasmodium spp parasites. We highlight the current progresses and viewpoints of these metal-based complexes, with a specific focus on drug discovery., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

This work deals with two new molecule-based materials, namely Ni II -complexes of general formulae [Ni(L1) 2 ] (Ni1) and [Ni(L2) 2 ] (Ni2), where L1 = trans-cinnamaldehyde-N(4)-methyl thiosemicarbazone and L2 = trans-cinnamaldehyde-N(4)-ethyl thiosemicarbazone, as potential antitumor agents. Both compounds were characterized by elemental analysis, molar conductivity and spectroscopic techniques (FTIR and NMR). Their molecular structures were obtained by single-crystal X-ray diffraction analysis. Each one crystallizes in a monoclinic space group P 2 1 /c, also the asymmetric unit comprises of one Ni II ion located on an inversion centre and one anionic ligand, which acts as a κ 2 N,S-donor affording a five-membered metallaring. The compounds were screened against two selected tumour cell lines (MCF-7 and A549) and non-tumour fibroblasts cell line (MRC-5) via MTT assays. In both tumour cells, all compounds exhibited higher cytotoxicity than the control drug (cisplatin). The IC 50 values ranges of 3.70 - 41.37 μM and 1.06 - 14.91 μM were found for MCF-7 and A549, respectively. Importantly, all of them were less toxicity than cisplatin in MRC-5 with SI values ranged at 11.80 - 86.60. The red blood cell (RBC) assay revealed Ni2 as non-toxic due to its reduced haemolytic effect (0--9% at 1--10 μM). The DNA binding was investigated through a combination of spectrophotometric absorption and emission titrations, electrophoresis, and circular dichroism experiments. As a result, these metal complexes were not able to strongly binding to DNA (K b values ~10 4  mol L - -1 ) but suggesting groove-binding interactions. The scavenging ability of them towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical was also evaluated in this work, but no important antioxidant behaviour was detected. Further, the interaction of Ni1 and Ni2 to human serum albumin (HSA) was explored by quenching of tryptophan emission, warfarin competitive assay, and molecular docking protocols. The HSA binding analyses indicated good affinity of both complexes to Sudlow site I (K b values ⁓10 3  mol L -1 )., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Bridge splitting reactions between [Pd(C 2 ,N-dmba)(μ-X)] 2 (dmba = N,N-dimethylbenzylamine; X = Cl, I, N 3 , NCO) and 2,6-lutidine (lut) in the 1:2 molar ratio at room temperature afforded cyclopalladated compounds of general formulae [Pd(C 2 ,N-dmba)(X)(lut)] {X = Cl - (1), I - (2), NNN - (3), NCO - (4)}, which were characterized by elemental analyses and infrared (IR), 1 H NMR spectroscopy. The molecular structures of all synthesized palladacycles have been solved by single-crystal X-ray crystallography. The cytotoxicity of the cyclopalladated compounds has been evaluated against a panel of murine {mammary carcinoma (4T1) and melanoma (B16F10-Nex2)} and human {melanoma (A2058, SK-MEL-110 and SK-MEL-5) tumor cell lines. All complexes were about 10 to 100-fold more active than cisplatin, depending on the tested tumor cell line. For comparison purposes, the cytotoxic effects of 1-4 towards human lung fibroblasts (MRC-5) have also been tested. The late apoptosis-inducing properties of 1-4 compounds in SK-MEL-5 cells were verified 24 h incubation using annexin V-Fluorescein isothiocyanate (FITC)/propidium iodide (PI). The binding properties of the model compound 1 on human serum albumin (HSA) and calf thymus DNA (ct-DNA) have been studied using circular dichroism and fluorescence spectroscopy. Docking simulations have been carried out to gain more information about the interaction of the palladacycle and HSA. The ability of compounds 1-4 to inhibit the activity of cathepsin B and L has also been investigated in this work., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Herein, a robust docking protocol was developed by using a low-cost workflow to highlight the modulation at ATPase domain from Human Topoisomerase-IIα (TOP2A) towards four novel Pd(II)-complexes bearing N,S-donor ligands. In vitro TOP2A inhibition assay confirmed the ability of them to prevent the enzyme functions into concentration ranging at 6.25-25μM. These results exhibited more effectivity than anticancer agent etoposide (35μM) and merbarone (40-50μM). The compounds were screened via Resazurin assay against MCF-7, MDA-MB-231 (Human breast), DU-145 (Human prostate), A549 (Human lung) and Cal27 (Human tongue) tumor cell lines revealing great cytotoxic effects, primarily to MCF-7 (IC 50 =1.81-4.46μM). As well, 1-4 exhibited their selectivity index (SI) higher than cisplatin against HEK-293 (human kidney) normal cells, at least 11.6-fold (SI 1-4 =1.4-5.0; SI cis =0.12). Further, Red Blood Cell hemolytic test suggested in vitro non-toxic character for compound 4, previously evaluated as the most effective TOP2A inhibitor., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: Evidence is lacking concerning the myriad surgical techniques for type 1 Chiari malformation. This study evaluated the impact of arachnoid violation with tonsil thermocoagulation during surgical craniovertebral junction decompression., Methods: The evaluation included aspects of the neurologic examination and parameters of cerebrospinal fluid flow on magnetic resonance imaging during preoperative and postoperative periods. All patients underwent craniovertebral junction decompression and opening of the dura mater. Patients were divided into 2 study groups. Patients in group 1 did not undergo arachnoid violation. Patients in group 2 underwent tonsil manipulation and systematic opening of the fourth ventricle outlet., Results: There were 16 patients enrolled in each group (total of 32 patients). Regarding clinical improvement, there were no significant differences between groups in the postoperative period. Group 2 had more adverse events (relative risk 2.45, 95% confidence interval 1.55-3.86). In terms of cerebrospinal fluid flow parameter analyses, patients in group 1 achieved better results (P < 0.05)., Conclusions: For treatment of symptomatic type 1 Chiari malformation, craniovertebral junction decompression with arachnoid preservation (i.e., without tonsillar manipulation) seems more suitable than the addition of arachnoid opening and thermocoagulation of the tonsils., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The reaction between 5-fluoro-isatin and hydroxyl-amine hydro-chloride in acidic ethanol yields the title compound, C 8 H 5 FN 2 O 2 , whose mol-ecular structure matches the asymmetric unit and is nearly planar with an r.m.s. deviation for the mean plane through all non-H atoms of 0.0363 Å. In the crystal, the mol-ecules are linked by N-H⋯N, N-H⋯O and O-H⋯O hydrogen-bonding inter-actions into a two-dimensional network along the (100) plane, forming rings with R 2 2 (8) and R 1 2 (5) graph-set motifs. The crystal packing also features weak π-π inter-actions along the [100] direction [centroid-to-centroid distance 3.9860 (5) Å]. Additionally, the Hirshfeld surface analysis indicates that the major contributions for the crystal structure are the O⋯H (28.50%) and H⋯F (16.40%) inter-actions. An in silico evaluation of the title compound with the vascular endothelial growth factor receptor-2 (VEGFR-2) was carried out. The title compound and the selected biological target VEGFR-2 show the N-H⋯O( GLU94 ), ( CYS96 )N-H⋯O(isatine) and ( PHE95 )N-H⋯O(isatine) inter-molecular inter-actions, which suggests a solid theoretical structure-activity relationship.

The acetic acid-catalyzed reaction between 5-chloro-isatin and 4-methyl-thio-semicarbazide yields the title compound, C 10 H 9 ClN 4 OS (I) (common name: 5-chloro-isatin-4-methyl-thio-semicarbazone). The mol-ecule is nearly planar (r.m.s. deviation = 0.047 Å for all non-H atoms), with a maximum deviation of 0.089 (1) Å for the O atom. An S (6) ring motif formed by an intra-molecular N-H⋯O hydrogen bond is observed. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains propagating along the a -axis direction. The chains are linked by N-H⋯S hydrogen bonds, forming a three-dimensional supra-molecular structure. The three-dimensional framework is reinforced by C-H⋯π inter-actions. The absolute structure of the mol-ecule in the crystal was determined by resonant scattering [Flack parameter = 0.006 (9)]. The crystal structure of the same compound, measured at 100 K, has been reported on previously [Qasem Ali et al. (2012 ▸). Acta Cryst. E 68 , o964-o965]. The Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are the H⋯H (23.1%), H⋯C (18.4%), H⋯Cl (13.7%), H⋯S (12.0%) and H⋯O (11.3%) inter-actions. A mol-ecular docking evaluation of the title compound with the ribonucleoside diphosphate reductase (RDR) enzyme was carried out. The title compound (I) and the active site of the selected enzyme show Cl⋯H-C (LYS140) , Cg (aromatic ring)⋯H-C (SER71) , H⋯O-C (GLU200) and Fe III ⋯O⋯Fe III inter-molecular inter-actions, which suggests a solid theoretical structure-activity relationship.

The equimolar reaction between 4-(di-methyl-amino)-benzaldehyde and 2-acetyl-thio-phene in basic ethano-lic solution yields the title compound, C 15 H 15 NOS, whose mol-ecular structure matches the asymmetric unit. The mol-ecule is not planar, the dihedral angle between the aromatic and the thio-phene rings being 11.4 (2)°. In the crystal, mol-ecules are linked by C-H⋯O and weak C-H⋯S inter-actions along [100], forming R 2 2 (8) rings, and by weak C-H⋯O inter-actions along [010], forming chains with a C (6) graph-set motif. In addition, mol-ecules are connected into centrosymmetric dimers by weak C-H⋯π inter-actions, as indicated by the Hirshfeld surface analysis. The most important contributions for the crystal structure are the H⋯H (46.50%) and H⋯C (23.40%) inter-actions. The crystal packing resembles a herringbone arrangement when viewed along [100]. A mol-ecular docking calculation of the title compound with the neuraminidase enzyme was carried out. The enzyme shows ( ASN263 )N-H⋯O, ( PRO245 )C-H⋯ Cg (thio-phene ring) and ( AGR287 )C-H⋯N inter-molecular inter-actions with the title compound. The crystal structure was refined as a two-component twin with a fractional contribution to the minor domain of 0.0181 (8).

There are two crystallographically independent mol-ecules in the asymmetric unit of the title compound, C 13 H 17 N 3 S, one of them being disordered over the methyl group [site-occupancy ratio = 0.705 (5):0.295 (5)]. The maximum r.m.s. deviations from the mean plane of the non-H atoms for the tetra-lone fragments amount to 0.4572 (17) and 0.4558 (15) Å. The N-N-C-N fragments are not planar and torsion angles are -9.4 (2) and 8.3 (2)°. In the crystal, the mol-ecules are linked by weak N-H⋯S inter-actions into chains along [100] with graph-set motif C (4) and connected by weak N-H⋯S and C-H⋯S inter-actions, forming R 2 1 (10) rings. The Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are the H⋯H (64.20%), H⋯S (12.60%) and H⋯C (12.00%) inter-actions. The crystal packing resembles a herringbone arrangement when viewed along [001].

The reaction between 5-nitro-isatin and phenyl-hydrazine in acidic ethanol yields the title compound, C 14 H 10 N 4 O 3 , whose mol-ecular structure deviates slightly from a planar geometry (r.m.s. deviation = 0.065 Å for the mean plane through all non-H atoms). An intra-molecular N-H⋯O hydrogen bond is present, forming a ring of graph-set motif S (6). In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen-bonding inter-actions into a two-dimensional network along (120), and rings of graph-set motif R 2 2 (8), R 2 2 (26) and R 4 4 (32) are observed. Additionally, a Hirshfeld surface analysis suggests that the mol-ecules are stacked along [100] through C=O⋯ Cg inter-actions and indicates that the most important contributions for the crystal structure are O⋯H (28.5%) and H⋯H (26.7%) inter-actions. An in silico evaluation of the title compound with the DHFR enzyme (di-hydro-folate reductase) was performed. The isatin-hydrazone derivative and the active site of the selected enzyme show N-H⋯O( ASP29 ), N-H⋯O( ILE96 ) and Cg ⋯ Cg ( PHE33 ) inter-actions.

In the title compound, C11H13N3O2S, there is a short intra-molecular N-H⋯N contact. The benzo[d][1,3]dioxole ring system is approximately planar (r.m.s. deviation = 0.025 Å) and makes a dihedral angle of 56.83 (6)° with the mean plane of the methyl-thio-semicarbazone fragment [-N-N-C(=S)-N-C; maximum deviation = 0.1111 (14) Å for the imino N atom]. In the crystal, mol-ecules are linked via pairs of N-H⋯S hydrogen bonds, forming inversion dimers. The dimers are connected by N-H⋯S hydrogen bonds into layers parallel to (100). The H atoms of both methyl groups are disordered over two sets of sites and were refined with occupancy ratios of 0.5:0.5 and 0.75:0.25.

In the title compound, C10H11N3O2S, the 1,3-benzodioxole and hydrazinecarbothio-amide fragments are nearly planar [(mean deviations from planarity for non-H atoms of 0.0325 (12) Å and 0.0707 (10) Å, respectively] and subtend a dihedral angle of 29.06 (5)°. In the crystal, mol-ecules are linked by pairs of almost linear N-H⋯S hydrogen bonds, forming inversion dimers. These dimers are additionally connected by weaker and strongly bent N-H⋯S inter-actions into chains along [101]. There is one additional weak N-H⋯O contact which, if considered as an inter-action, leads to the formation of a three-dimensional network.

The effects of the intermittency of water flow on habitat structure and substrate composition have been reported to create a patch dynamics for the aquatic fauna, mostly for that associated with the substrate. This study aims to describe the spatial distribution of Chironomidae in an intermittent river of semiarid Brazil and to associate assemblage composition with environmental variables. Benthic invertebrates were sampled during the wet and dry seasons using a D-shaped net (40 cm wide and 250 μm mesh), and the Chironomidae were identified to genus level. The most abundant genera were Tanytarsus, Polypedilum, and Saetheria with important contributions of the genera Procladius, Aedokritus, and Dicrotendipes. Richness and density were not significantly different between the study sites, and multiple regression showed that the variation in richness and density explained by the environmental variables was significant only for substrate composition. The composition of genera showed significant spatial segregation across the study sites. Canonical Correspondence Analysis showed significant correspondence between Chironomidae composition and the environmental variables, with submerged vegetation, elevation, and leaf litter being important predictors of the Chironomidae fauna. This study showed that Chironomidae presented important spatial variation along the river and that this variation was substantially explained by environmental variables associated with the habitat structure and river hierarchy. We suggest that the observed spatial segregation in the fauna results in the high diversity of this group of organisms in intermittent streams.

Background: The complexity of reentrant circuits related to ventricular tachycardias decreases the success rate of radiofrequency ablation procedures., Objective: To evaluate whether the epicardial mapping with multiple electrodes carried out simultaneously with the endocardial mapping helps in ablation procedures of sustained ventricular tachycardia (VT) in patients with nonischemic heart disease., Methods: Twenty-six patients with recurrent sustained VT, of which 22 (84.6%) presenting chronic chagasic cardiomyopathy, 2 (7.7%) with idiopathic dilated cardiomyopathy and 2 with right ventricular arrhythmogenic dysplasia (RVAD), were submitted to epicardial mapping with two or three microcatheters, with 8 electrodes each, simultaneously to the conventional endocardial mapping. A catheter with a 4-mm tip was used for the ablation by radiofrequency (RF) carried out during the induced VT., Results: Of the 33 induced VT, 25 were mapped and 20 had their origin defined. Eleven had epicardial and 9 had endocardial origin. The programmed ventricular stimulation did not induce sustained VT in 11 (42.0%) of the 26 patients after the ablation. Events such as VT recurrence and death occurred in 10.0% of the patients submitted to successful ablation and in 59.0% of the unsuccessful cases, during a mean ambulatory follow-up of 357 ± 208 days., Conclusion: Subepicardial circuits are frequent in patients with nonischemic heart disease. The epicardial mapping with multiple catheters carried out simultaneously with the endocardial mapping contributes to the identification of these circuits in a same procedure.

Non-Markovian stochastic Langevin-like equations of motion are compared to their corresponding Markovian (local) approximations. The validity of the local approximation for these equations, when contrasted with the fully nonlocal ones, is analyzed in detail. The conditions for when the equation in a local form can be considered a good approximation are then explicitly specified. We study both the cases of additive and multiplicative noises, including system-dependent dissipation terms, according to the fluctuation-dissipation theorem.

Objective: To demonstrate the feasibility and safety of simultaneous catheterization and mapping of the 4 pulmonary veins for ablation of atrial fibrillation., Methods: Ten patients, 8 with paroxysmal atrial fibrillation and 2 with persistent atrial fibrillation, refractory to at least 2 antiarrhythmic drugs and without structural cardiopathy, were consecutively studied. Through the transseptal insertion of 2 long sheaths, 4 pulmonary veins were simultaneously catheterized with octapolar microcatheters. After identification of arrhythmogenic foci radiofrequency was applied under angiographic or ultrasonographic control., Results: During 17 procedures, 40 pulmonary veins were mapped, 16 of which had local ectopic activity, related or not with the triggering of atrial fibrillation paroxysms. At the end of each procedure, suppression of arrhythmias was obtained in 8 patients, and elimination of pulmonary vein potentials was accomplished in 4. During the clinical follow-up of 9.6+/-3 months, 7 patients remained in sinus rhythm, 5 of whom were using antiarrhythmic drugs that had previously been ineffective. None of the patients had pulmonary hypertension or evidence of stenosis in the pulmonary veins., Conclusion: Selective and simultaneous catheterization of the 4 pulmonary veins with microcatheters for simultaneous recording of their electrical activity is a feasible and safe procedure that may help ablation of atrial fibrillation.

We present an unusual case of thoracic constrictive arachnoiditis after pantopaque myelography, used 10 years before in the diagnosis of intradural arachnoid cyst.