Internal Consistency of Yesavage Geriatric Depression Scale (GDS 15-Item Version) in Ecuadorian Older Adults.

The present study aimed to assess the validity of a Spanish version of the Geriatric Depression-15 Scale (GDS-15) in Ecuadorian adults. Cross-sectional study to validate GDS-15 in its short version (GDS-15). Internal consistency and factor structure were assessed through Kuder Richardson 20 and Confirmatory Factor Analysis. A total of 211 subjects 65 years of age and older participated in the validation process. Internal consistency was adequate, the Kuder Richardson 20 coefficient for the total scale was 0.73. Three factor structure was found for the scale. This study highlights the importance of having a validated scale for screening depression in the elderly. This study provides an evidence for the use of GDS-15 in Ecuadorian elderly population to screen for depression.

Calidad del sellado apical del conducto radicular comparando dos cementos endodónticos mediante microscopio electrónico de barrido / Apical sealing quality of the root canal by comparing two endodontic sealers evaluated by scanning electron microscope / Qualidade do selamento apical do canal radicular comparando dois cimentos endodônticos avaliados por microscopia eletrônica de varredura

El desarrollo de nuevos cementos de obturación radicular tiene como finalidad conseguir un sellado hermético y obturación tridimensional, siendo fundamental para evitar la microfiltración bacteriana y posibles fracasos del tratamiento endodónti-co. Objetivo: Comparar la calidad de sellado de obturación entre dos tipos de cementos: resinoso y biocerámico a 1mm y 4mm del ápice radicular. Materiales y métodos: Se utilizó una muestra de 40 primeros premolares uniradiculares, donados por una clínica particular de la ciudad de Quito- Ecuador. Se dividieron en dos grupos de 20 dientes cada uno, se estanda-rizó la porción radicular a 16 mm y se conformó endodónticamente con el sistema rotatorio MTwo (VDW), la obturación fue por la técnica de cono único con diferentes cementos siendo: G1: Cemento biocerámico Total Fill BC Sealer (FKG) y G2: Cemento resinoso Top seal (Dentsply). Se seccionó transversalmente las raíces con un micrótomo a 1 y 4 mm del ápice, la calidad del sellado de los cortes se evaluó con Microscopio Electrónico de Barrido (MEB). Los datos se analizaron mediante la prueba estadística ANOVA, con un nivel de significancia de 5%. Resultados: La calidad del sellado del tercio apical radicular a 1 mm del ápice fue de 4,70 ± 1,54 µm y 6,95 ± 2,69 µm para G1 y G2 respectivamente (p=0.003), en la distancia de 4 mm del ápice radicular fue de 8,50 ± 4,54 µm y 9,70 ± 3,24 µm para G1 y G2 respectivamente (p=0.383). Conclusión: La calidad del sellado fue mejor a 1 mm de apical en el cemento biocerámico; sin embargo, a 4 mm no se observó diferencia estadísticamente significativa entre los cementos.

The purpose of the development of new root filling sealers is to achieve a hermetic sealing and three-dimensional obtu-ration, which is essential to avoid bacterial microfiltration and possible failures of endodontic treatment. Objective: To compare the sealing quality of obturation root canal between two sealers: resinous and bioceramic at 1mm and 4mm at the root apex. Materials and methods: Forty first mandibular premolars, donated by a clinic in the city of Quito, Ecuador, was used. The samples were divided into two groups of 20 teeth each, the root canal was standardized to 16 mm and shaped using MTwo rotary system (VDW), the obturation was by the single cone technique with different endodontic sealers: G1: Bioceramic Total Fill BC Sealer (FKG) and G2: resinous Top seal sealer (Dentsply). The roots were cut transversally at 1 and 4 mm from the apex using a microtome, and the sealing quality of the sections was evaluated with a Scanning Elec-tronic Microscope (SEM). The data were analyzed using the ANOVA statistical test at significance level of 5%. Results:The apical sealing quality at 1 mm from the apex was 4.70 ± 1.54 µm and 6.95 ± 2.69 µm for G1 and G2 respectively (p = 0.003), and 8.50 ± 4.54 µm and 9.70 ± 3.24 µm at 4 mm for G1 and G2 respectively (p = 0.383). Conclusion: The apical sealing quality of the bioceramic sealer was better than resinous sealer at 1 mm from apex; however, both bioceramic and resinous sealers was similar at 4 mm from apex.

O desenvolvimento de novos cimentos para obturação do radicular tem como finalidade obter selamento hermético e ob-turação tridimensional, o que é essencial para evitar a microfiltração bacteriana e possíveis falhas do tratamento endodôn-tico. Objetivo: Comparar a qualidade do selamento entre dois tipos de cimentos: resinoso e biocerâmico a 1mm e 4mm no ápice radicular. Materiais e métodos: Quarenta primeiros pré-molares unirradiculares, doados por uma clínica particular na cidade de Quito, Equador, foram utilizados. As amostras Foram divididas em dois grupos de 20 dentes , o canal radicular foi padronizado em 16 milímetros e preparados utilizando sistema rotatório Mtwo (VDW), a obturação foi realizada pela técnica de cone único com diferentes cimentos endodônticos: G1: Cimento biocerâmico Total Fill BC Sealer (FKG) e G2: cimento resinoso Top Seal (Dentsply). As raízes foram seccionadas transversalmente com um micrótomo a 1 e 4 mm do ápice, e a qualidade de selamento das seções foi avaliada com um Microscópio Eletrônico de Varredura (MEV). Os dados foram analisados pelo teste estatístico ANOVA, com nível de significância de 5%. Resultados: A qualidade do selamento apical a 1 mm do vértice radiográfico foi de 4,70 ± 1,54 µm e de 6,95 ± 2,69 µm para G1 e G2, respectivamente (p = 0.003), e de 8,50 ± 4,54 µm e 9,70 ± 3,24 µm a 4 mm para G1 e G2, respectivamente (p = 0.383). Conclusão: A qualidade de apical selamento do cimento biocerâmico foi melhor que o resinoso a 1 mm de ápice; porém, eles foram semelhantes a 4 mm do ápice.

Dynamics of dissolution and diffusion-controlled drug release systems.

Analytical expressions were derived to explain the influence of the dissolution/diffusion number (Di) on the time constant and steady-state flux when dispersed drugs are released from a finite matrix. A key novelty of this work is the introduction of a single time-constant that combined the analysis of both dissolution- and diffusion-based systems. Focus is placed on systems with a constant dissolution rate and diffusion coefficient. Solutions, based on the residue theorem, were in agreement with published results describing the transport of estradiol in a polymeric matrix. The experimental cumulative amount of drug released was 0.1 mg/cm² in 100 hours compared to 0.084 mg/cm² predicted by the theoretical model. The process time constant, estimated from the first eigenvalue (t0) and a more accurate statistical approach (t(eff)), showed a consistent decrease with increasing Di values. For a dissolution/diffusion number of 0.21, t0 and t(eff) were estimated at 58.44 and 73.02 hrs, respectively. With the presence of a skin layer, t(eff) increased to 575.7 hrs. These results can be used to assess the relative impact of dissolution and diffusion on the time it takes drugs to attain a therapeutic level in the bloodstream.

Guía de bioseguridad para laboratorios clínicos / Biosecurity Guidelines for Clinical Labortatories

Vías de infección.- Clasificación de laboratorios.- Procedimientos de seguridad.- Manejo de muestras biológicas.- Limpieza y desinfección.- Accidentes de trabajo.- Manejo de desechos.- Recursos humanos y físicos.- Bioética y control de calidad