RESUMEN

This study focuses on the use of Density Functional Theory calculations with two main approaches: computational chemistry and computational physics. The following three cases were considered for the derivation: (I) computational chemistry using the M06 hybrid functional, (II) computational chemistry using the standard PBE functional including vdW interactions, and (III) computational physics using the standard PBE functional including vdW interactions and periodic boundary conditions. Since the approximation using hybrid functionals M06 has been extensively validated, this method was used as a reference. The second and third methods are less expensive, it is ideal for use to extend large systems. From the sensitized molecules are found in the gas phase and include solvent effects through the integral equation formalism polarizable continuum model. In a systematic analysis of 15 Cu complex molecules, a complete characterization for DSSCs has been carried out and molecular geometry, electronic and optical measurements have been reported.

Asunto(s)

Cobre , Teoría Cuántica , Cobre/química , Interacciones Hidrofóbicas e Hidrofílicas

RESUMEN

INTRODUCTION AND AIM: Helicobacter pylori (H. pylori) is known to be capable of causing chronic inflammation of the gastric mucosa that slowly progresses through the premalignant stages, reaching localized gastric adenocarcinoma (GAC). Its outcome is closely related to the stage at which diagnosis is made. The aim of the present study was to determine cost-benefit by comparing esophagogastroduodenoscopy, serum pepsinogen detection, and no screening at all. MATERIAL AND METHODS: Utilizing Markov chains and Monte Carlo simulation, the costs and effects of various detection modalities were simulated to analyze the cost-benefit of each strategy. For our population, we used the published data of patients with gastric cancer, applicable to the Mexican population. RESULTS: The results were reported as incremental cost-effectiveness ratios. The best strategy was serum pepsinogen determination, followed by the strategy of endoscopic examination with continued monitoring every 3 years. CONCLUSIONS: The performance of serum pepsinogen serology and directed endoscopic examination (and continued monitoring, if necessary) for GAC screening could be a cost-effective intervention in Mexico, despite the low-to-moderate general prevalence of the disease.

Asunto(s)

Adenocarcinoma , Infecciones por Helicobacter , Neoplasias Gástricas , Adenocarcinoma/diagnóstico , Adenocarcinoma/epidemiología , Análisis Costo-Beneficio , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Humanos , México , Pepsinógeno A , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/epidemiología

RESUMEN

INTRODUCTION AND AIM: Helicobacter pylori (H. pylori) is known to be capable of causing chronic inflammation of the gastric mucosa that slowly progresses through the premalignant stages, reaching localized gastric adenocarcinoma (GAC). Its outcome is closely related to the stage at which diagnosis is made. The aim of the present study was to determine cost-benefit by comparing esophagogastroduodenoscopy, serum pepsinogen detection, and no screening at all. MATERIAL AND METHODS: Utilizing Markov chains and Monte Carlo simulation, the costs and effects of various detection modalities were simulated to analyze the cost-benefit of each strategy. For our population, we used the published data of patients with gastric cancer, applicable to the Mexican population. RESULTS: The results were reported as incremental cost-effectiveness ratios. The best strategy was serum pepsinogen determination, followed by the strategy of endoscopic examination with continued monitoring every 3 years. CONCLUSIONS: The performance of serum pepsinogen serology and directed endoscopic examination (and continued monitoring, if necessary) for GAC screening could be a cost-effective intervention in Mexico, despite the low-to-moderate general prevalence of the disease.