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1.
J Inorg Biochem ; 237: 112015, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36191435

RESUMEN

The present work reports the synthesis and investigation by semi-empirical Density Functional Theory (DFT), physical chemistry, and spectroscopic methods of two dithiocarbazates, 2-acetylpyridine-S-p-bromobenzyl-dithiocarbazate (HL1) and 2-acetylpyridine-S-p-nitrobenzyl-dithiocarbazate (HL2) and their Cu(II) complexes, [Cu(L1)Cl] (1), [Cu(L1)Br] (2), [Cu(L2)Cl] (3) and [Cu(L2)Br] (4). Single crystal X-ray analyzes showed distorted square planar geometry to the metal centers, which tridentate ligands coordinated by the NNS system and an additional halogen (Cl- or Br-) to complete the coordination sphere. Mass spectrometry data indicated the presence of [Cu(L1)(DMF)]+ and [Cu(L2)(DMF)]+, due to the exchanging of chloride/bromide ions and characteristic fragmentations of the compounds. The DFT composite method B97-3c was employed to optimize the geometries of ligands and complexes and IR spectra were calculated revealing good agreement with experimental data. Hydrogen bonds and π⋅⋅⋅π stacking interactions upon the molecular packing were investigated by Hirshfeld surface and fingerprint plots with the main interactions attributed to the H⋅⋅⋅H contacts. The biological activity of the dithiocarbazates and their Cu(II) complexes were evaluated in vitro against the human glioma U251 cells. Results revealed that the free dithiocarbazates present great in vitro antitumor activity that is increased after the complexation with copper. The measurement of cytotoxicity of the compounds showed biological activity in a low range of concentration, which indicates high efficiency as potential drugs.


Asunto(s)
Complejos de Coordinación , Cobre , Humanos , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Cobre/química , Cristalografía por Rayos X , Halógenos , Enlace de Hidrógeno , Ligandos , Metales/química
2.
Int. j. med. surg. sci. (Print) ; 4(1): 1089-1099, mar. 2017. ilus, graf, tab
Artículo en Español | LILACS | ID: biblio-1284298

RESUMEN

La ultrasonografía es un método de evaluación rápido y eficaz en los departamentos de emergencias, siempre en manos entrenadas. La lesión vascular periférica es un cuadro que en lo que trauma se refiere, debe tener un veloz diagnóstico y tratamiento por los riesgos que significa: En lesiones abiertas, la hemorragia; y en lesiones cerradas se añade el síndrome compartimental. Lograr la evaluación de la indemnidad o no del árbol vascular en los miembros, se torna importante a la hora de prevenir eventos que requieran intervención quirúrgica (reparación y/o fasciotomía). El objetivo de este trabajo consiste en demostrar la utilidad del conocimiento del árbol vascular periférico y su evaluación mediante doppler para el manejo del trauma vascular periférico, mental (n=77) = 11 (14,78 %). Resolución: lesión vascular = 1 (1,3 %) síndrome compartimental= 1 (1,3 %) con resolución quirúrgica. La utilización de la ultrasonografía y del doppler para la evaluación vascular periférica es útil para el reconocimiento precoz del riesgo a desarrollar desde una lesión vascular simple hasta un síndrome compartimental. La utilización de listas de verificación durante la simulación para la generación del criterio, son útiles en la formación de residentes de cirugía


Report the recurrence rate ofnegative pressure subdural drainage (NPSD) versusto other kind of drains (OD). Design and Methods: Astudy was conducted cross-sectional and weretrospectively analyzed on the database of theneurosurgical service and we looked for all surgicalprocedures recorded from January 2006 to December2015. Procedures with preoperative diagnosis ofsubdural hematoma (SDH) were selected, with a to-tal of 364 interventions, were excluded patients withpostoperative diagnosis different from SDH andeliminated those who did not have complete data,recurrence was identified, a statistical analysis wasperformed describing frequency measurementspercentage and standard deviation, RM and chi-square was obtained by software EPIDAT 3.1. 277 surgeries were performed in 230 patients, Thepopulation was divided into two groups: the first thoseinterventions with negative pressure subduraldrainage versus a second group with other differentdrains, and finally we compared the recurrence ratein each group, 44 surgeries had recurrence of SDH.The proportion of recurrence was found 16 % of thesurgeries, 16 % (n=7) of these were performed withnegative pressure subdural drainage and theremaining 84 % (n=37) by other drainage. The reasonfor prevalence found was 0.36 (95 % CI , 0.15 to0.85), with statistically significant differences (p =0.0165). The chi-square was 5.75 for the SDH withNPSD. It was found that patients treated with NPSDhave a lower risk of recurrence compared with OD,which acts as a protective factor for patients treatedwith this type of drain, this is statistically significant.


Asunto(s)
Humanos , Hematoma Subdural Crónico/diagnóstico , Hematoma Subdural Crónico/terapia , Recurrencia , Drenaje , Estudios Transversales
3.
Cir Cir ; 85 Suppl 1: 49-52, 2017 Dec.
Artículo en Español | MEDLINE | ID: mdl-28043642

RESUMEN

INTRODUCTION: Schwannomas are benign tumours that are relatively common in the head, however the involvement of the sinunasal region is rare and there are only 5 cases reported in the maxilla in current literature, representing less than 1% of bone tumours. CLINICAL CASE: We report the case of a woman with a right maxillary schwannoma who underwent a complete resection of the lesion. Emphasis is placed on the rarity of the lesion in terms of its location and includes a review of clinical behaviour, diagnosis and current treatment options. CONCLUSIONS: Maxillary trigeminal schwannoma must be suspected if vague sinunasal symptoms, paranasal mass or, as in this case, trigeminal neuralgia present. Surgical treatment is indicated, and approaches vary according to location and tumour size.


Asunto(s)
Neoplasias de los Nervios Craneales/cirugía , Nervio Maxilar/cirugía , Neurilemoma/cirugía , Anciano , Neoplasias de los Nervios Craneales/clasificación , Neoplasias de los Nervios Craneales/diagnóstico por imagen , Neoplasias de los Nervios Craneales/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Nervio Maxilar/diagnóstico por imagen , Nervio Maxilar/patología , Seno Maxilar/cirugía , Invasividad Neoplásica , Neurilemoma/clasificación , Neurilemoma/diagnóstico por imagen , Neurilemoma/patología , Fosa Pterigopalatina/cirugía
4.
Int. j. med. surg. sci. (Print) ; 3(3): 963-970, sept. 2016. ilus, tab
Artículo en Español | LILACS | ID: biblio-1094875

RESUMEN

El objetivo del trabajo fue escribir la técnica quirúrgica y reportar la experiencia de nuestro hospital en el uso del abordaje pterional modificado como primera elección para el clipaje de aneurismas del círculo arterial cerebral en cualquier ubicación e incluso múltiples. Realizamos un estudio retrospectivo y reportamos una serie de 37 pacientes (25 mujeres y 12 hombres) con diagnóstico de aneurismas derivados del círculo arterial cerebral de distintas ubicaciones, desde enero del 2012 hasta marzo del 2015. Se presenta la experiencia de 51 aneurismas incluidos 8 casos de aneurismas múltiples y 9 aneurismas gigantes.Todos los aneurismas fueron clipados mediante un abordaje pterional modificado. Se describieron yesquematizaron los pasos del procedimiento quirúrgico secuencialmente. Mediante este análisis se estableceque el abordaje frontotemporoesfenoidal modificado (pterional) permite el acceso quirúrgico para el clipajede estas lesiones vasculares provenientes del círculo arterial cerebral lo cual correlaciona con la evidencia previa. La descripción detallada de la técnica quirúrgica favorece una adecuada comprensión de la anatomía quirúrgica y permite la reproducción de esta técnica.


The objective of the study was to describe our surgical and technical experience by reporting a series of 51 aneurysms treated by a pterional craniotomy as a unique approach foraneurismatic lesions of the cerebral arterial circle (Willis polygon). Retrospective study that reportsa series of 37 patients (25 females and 12 males) with diagnosis of aneurismatic lesions from different localization in the Willis polygon from January 2012 to March 2015. Fifty one (51)aneurismatic lesions were treated by a unique pterional craniotomy, including 8 cases of multiple aneurismatic disease and 9 giant aneurysms. Every lesion was clipped by the same pterional modified approach. Every step of this procedure was described and illustrated sequentally. This analysis establishes that the modified fronto temporoesfenoidal (pterional) craniotomy allows surgical access to the clipping of these vascular lesions, from the circle of Willis which correlates with previous evidence. The detailed description of the surgical technique promotes a proper understanding of surgical anatomy and allows playback of this technique.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Aneurisma Intracraneal/cirugía , Círculo Arterial Cerebral/cirugía , Craneotomía/métodos , Estudios Retrospectivos , Resultado del Tratamiento
5.
Environ Technol ; 36(19): 2468-76, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25827467

RESUMEN

The main problem linked to the stability of upflow anaerobic sludge blanket (UASB) reactors during the treatment of Tequila vinasse is the high acidity and the null alkalinity present in this effluent. This research evaluates the effect of alkalinity and volatile fatty acids (VFAs) concentration on the performance of an UASB reactor with recirculation of the effluent for removing organic matter and biogas production from Tequila vinasses. Recirculation of the effluent reduces the impact of VFAs and organic matter concentration present in the influent, inducing the stability of the reactor. The UASB reactor was operated during 235 days at organic loading rates from 2.5 to 20.0 kg m(-3) d(-1), attaining a removal efficiency of COD greater than 75% with a methane yield of 335 ml CH4 g(-1) COD at SPT, maintaining a ratio of VFAs/Alk ≤ 0.5. Therefore, an optimal ratio of VFAs/Alk was established for the system operating in stable conditions for the treatment of Tequila vinasses. Under these conditions, the alkalinity was recuperated by the system itself, without the addition of external alkalinity.


Asunto(s)
Reactores Biológicos , Residuos Industriales/análisis , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Bebidas Alcohólicas , Anaerobiosis , Análisis de la Demanda Biológica de Oxígeno , Ácidos Grasos Volátiles/análisis , Concentración de Iones de Hidrógeno , Metano/análisis , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/instrumentación
6.
J Mol Model ; 20(7): 2298, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24939466

RESUMEN

In this work, we performed a thorough investigation of potential energy curves, rovibrational spectra, and spectroscopic constants for dimers whose interactions are mediated by hydrogen bonds and other hydrogen interactions. Particularly, we deal with CH4⋯CH4, CH4⋯H2O, CH4⋯CHF3, and H2O⋯CHF 3 dimers by employing accurate electronic energy calculations with two different basis sets at the MP2 level of theory. Following this, the discrete variable representation method was applied to solve the nuclear Schrödinger equation, thus obtaining spectroscopic constants and rovibrational spectra. The harmonic constant, ω e , presents a direct relation to the strength of dimer interactions. As a general rule, it was found that a decrease of interatomic distances is followed by the increase of D e for all dimers. This behavior suggests that the interaction of CH4⋯CH4 is the weakest among all dimers, followed by CH4⋯CHF3, CH4⋯H2O and the strongest interaction given by the H2O⋯CHF 3 dimer.

7.
Edumecentro ; 5(1): 47-54, ene.-abr. 2013. ilus
Artículo en Español | LILACS | ID: lil-679913

RESUMEN

Se realiza un estudio de corte pedagógico, con el objetivo de precisar momentos históricos de la Facultad de Medicina de Timor Leste. Los datos se obtuvieron a través de la observación, entrevista a informantes claves y la revisión documental. Con la participación de los profesionales de la brigada médica cubana en el mencionado país, se ejecutó el nuevo programa de formación de médicos, el cual se había iniciado en la Universidad Barrio Adentro de la República Bolivariana de Venezuela y en las facultades inauguradas para la formación de médicos de Cuba, y el resto del mundo. Con relación al postgrado se logró la formación de 100 residentes cubanos como especialistas en Medicina General Integral y dos versiones del diplomado en Educación Médica.


A pedagogical study was carried out with the objective to determine the historical moments of the Medicine Faculty in East Timor. The data were collected through the observation, interviews and documents review, with the participation of the professionals of the Cuban medical brigade in this country. A new program for the formation of doctors was carried out; it had started in the Inside the Neighborhood University in the Venezuelan Republic and in the faculties for the formation of doctors in Cuba, and in the rest of the world. In relation to the postgraduate, a hundred Cuban specialists were formed as residents in Integral General Medicine and two versions of the specialized course in medical education.


Asunto(s)
Administración de Personal , Educación Médica , Capacitación Profesional
8.
J Phys Chem A ; 113(52): 14818-23, 2009 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-19670828

RESUMEN

We have studied systems with typical hydrogen bonding and others with interaction involving hydrogen. CH(4)-CH(4), CH(4)-H(2)O, CHF(3)-CH(4), and CHF(3)-H(2)O dimers were studied using MPWB1K, PBE1PBE, MP2, and QCISD levels of theory with a large number of basis functions. The Pople 6-31+G(2d), 6-311++G(2d,2p), and 6-311++G(3df,3pd) as well as Dunning augmented aug-cc-pVDZ and aug-cc-pVTZ basis sets were used. The dimer geometries were fully optimized. An optimal basis set was determined for these systems to achieve a suitable compromise between accuracy and computational feasibility. A proper strategy was found for the electronic property calculations of dimers studied: the use of aug-cc-pVDZ as the optimal basis set at MP2 level. Dipole moments, polarizabilities, BSSE effects, and DeltaZPE were also analyzed for these dimers.


Asunto(s)
Clorofluorocarburos de Metano/química , Dimerización , Metano/química , Teoría Cuántica , Agua/química , Modelos Moleculares , Conformación Molecular , Termodinámica
9.
J Chem Inf Comput Sci ; 42(6): 1370-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12444734

RESUMEN

A fast iterative algorithm to obtain topological atomic and molecular descriptors, called Qcodes, is presented in this work. Its linear time dependence with the size of the structures and low memory requirement allows practical use for small molecules as well as macromolecular systems. The descriptors are unique and are able to sense small topological changes in atom's neighborhood. These properties make them suitable as atom and molecular identifiers to be used in database searching, force field atom typing, isomorphism, and automorphism algorithms. Examples of descriptors, their convergence behavior, sensitivity, ambiguity, and algorithm's performance are shown in this paper.

10.
Endoscopia (México) ; 9(2): 69-72, abr.-jun. 1998. tab, graf
Artículo en Español | LILACS | ID: lil-248141

RESUMEN

El sangrado variceal representa hasta al 30 por ciento de los sangrados de tubo digestivo alto, ocasiona la muerte hasta en una tercera parte de los pacientes que son internados para su tratamiento y se relaciona con complicaciones más severas que las ocasionadas por cualquier otra hemorragia de localización proximal. El manejo endoscópico de estos pacientes básicamente se concretaba a la escleroterapia, sin embargo, actualmente se considera que la ligadura es el método de elección tanto para el control de las várices esofágicas por las ventajas que ofrece sobre sobre la escleroterapia. El objetivo de este estudio fue demostrar si los resultados reportados eran reproductibles en nuestro medio por lo que se tomó una muestra al azar de 20 pacientes con antecedentes de sangrado reciente de origen variceal, a los que se les sometió a ligadura para control de la hemorragia aguda y posteriormente tratamiento para alcanzar la erradicación de las várices esofágicas, obteniéndose control de la hemorragia aguda en 100 por ciento de los casos, erradicación de los paquetes varicosos en el 90 por ciento con un número de sesiones menor que lo esperado con la escleroterapia y con un menor número de complicaciones. No se presentaron eventos de resangrado en ninguno de los pacientes y no hubo decesos relacionados con el procedimiento


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Endoscopía , Hemorragia/etiología , Hemorragia/terapia , Ligadura , Escleroterapia , Várices Esofágicas y Gástricas/terapia
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