Piezoelectric actuators for bone mechanical stimulation: exploring the concept.

Arthroplasty is liable to cause intense changes on strain levels and distribution in the boné surrounding the implant, namely stress shielding. Several solutions have been proposed for this, namely design variations and development of controlled-stiffness implants. A new approach to this problem, with potential application to other orthopaedic problems and other medical fields, would be the development of smart implants integrating systems for bone mechanical stimulation. Ideally, the implant should presente sensing capability and the ability to maintain physiological levels of strain at the implant interface. Piezoelectric materials’ huge potential as a mean to produce direct mechanical stimulation lies on the possibility of producing stimuli at a high range of frequencies and in multiple combinations. The present in vitro and preliminary in vivo studies were a first step towards the validation of the concept

Reprodutibilidade e Validade da Versão Portuguesa da Escala de Fragilidade de Edmonton em Doentes de Cirurgia Cardíaca

Introduction: Frailty is a multidimensional syndrome characterized by the loss of functional reserve, associated with higher mortality and less functional survival in cardiac surgery patients. The Edmonton Frail Scale (EFS) is a comprehensive tool devised for brief frailty detection. To the best of our knowledge, there are no culturally adapted and validated frailty screening tools that enable the identification of vulnerability domains suited for use in the preoperative setting in Portugal. This was the motivation for this study. Objectives: To assess the validity and reproducibility of the Portuguese version of the EFS. Methods: Prospective observational study, in a sample of elective cardiac surgery patients. The Edmonton Frail Scale (EFS) translation and backtranslation were performed. Demographic and clinical data were collected, and the translated EFS translated, Geriatric Depression Scale, and Mini Mental State Examination Portuguese versions, Katz and Clinical Frailty Scales were administered. To assess validity Mann-Whitney test, Spearman's correlation coefficient, marginal homogeneity test and Kappa coefficient were employed. Reproducibility was assessed estimating kappa coefficient for the frailty diagnosis and the 11 EFS items. Intra-class correlation coefficients and the corresponding 95% confidence interval were estimated using linear mixed effects model. Results: The EFS Portuguese version revealed construct validity for frailty identification, as well as criterion validity for cognition and mood domains. Reproducibility was demonstrated, with k=0.62 (95% confidence interval (CI) 0.42-0.82) and intraclass correlation (ICC)=0.94 (95% CI 0.89-0.97) in inter-observer test and k=0.48 (95% CI 0.26-0.70) and ICC=0.85 (95% CI 0.72-0.92) in intra-observer test. Conclusions: The EFS Portuguese version is valid and reproducible for use, suiting pre-operative frailty screening in a cardiac surgery setting.Introdução: A fragilidade é uma síndrome multidimensional caracterizada pela perda de reserva funcional, associada a maior mortalidade e menor sobrevivência funcional após cirurgia cardíaca. A Escala de Fragilidade de Edmonton (EFS) é uma ferramenta abrangente de deteção de fragilidade. Não existe ainda em Portugal uma ferramenta de rastreio culturalmente adaptada e validada que permita a identificação de domínios específicos de vulnerabilidade para utilização no pré-operatório. Objetivos: Avaliar a validade e reprodutibilidade da versão portuguesa da EFS. Métodos: Estudo prospetivo observacional, realizado numa amostra de doentes propostos para cirurgia cardíaca. A EFS foi traduzida e retrotraduzida. Colheram-se dados demográficos e clínicos, aplicaram-se as versões traduzidas da EFS, Escala de Depressão Geriátrica e MMSE, as escalas de Katz e Clinical Frailty Scale. Validade avaliada utilizando o teste de Mann-Whitney, o coeficiente de correlação de Spearman, o teste de homogeneidade marginal e o coeficiente Kappa. Reprodutibilidade avaliada pelo cálculo do coeficiente kappa para o diagnóstico de fragilidade e para os 11 itens da escala. Coeficientes de correlação intraclasse e correspondentes intervalos de confiança a 95% estimados usando um modelo linear de efeitos mistos. Resultados: A versão portuguesa da EFS demonstrou validade de constructo, assim como validade de critério nos domínios de cognição e humor. É reprodutível, com k=0,62 (95% IC 0,42-0,82) e CCI=0,94 (95% IC 0,89-0,97) no teste interobservador e k=0,48 (95% IC 0,26-0,70) e CCI=0,85 (95% IC 0,72-0,92) no teste intraobservador. Conclusões: A versão portuguesa da EFS é adequada para rastreio pré-operatório de fragilidade em cirurgia cardíaca.info:eu-repo/semantics/publishedVersio

Perioperative tumor cell dissemination in patients with primary or metastatic colorectal cancer

INTRODUCTION: Although there is general correlation between the TNM stage of colorectal cancer (CRC) and its prognosis, there is often significant variability of tumor behaviour and individual patient outcome, which is unaccounted for by pathologic factors alone. Our aim was to estimate perioperative tumor cell dissemination in patients with primary or CRC liver metastases as a possible factor influencing the outcome. METHODS: Forty patients were prospectively enrolled in the study from the year 2007 to 2008. Eighteen patients had histologically proven CRC (50% rectal, 44% colonic, 6% colonic and rectal). Sixteen patients (47%) had CRC liver metastases only. The remaining six patients who underwent colon or liver resection for benign conditions, acted as the control group. All patients with malignant pathologies had R0 resections. Blood samples were taken before the surgical incision (T0), immediately after tumor resection (T1) and at the end of the surgical intervention (T2). Data acquisition was performed using a dual-laser FACSCalibur flow cytometer. Circulating malignant cells were identified as being CD45-/cytokeratin+. RESULTS: The analysis of patients overall (CRC resection subgroup and hepatectomy subgroup) revealed that there was no statistically significant difference of the tumoral cell count in the blood per million of hematopoietic cells at T0, T1 and T2. CONCLUSIONS: This study demonstrates no differences in the detected circulating numbers of tumor cells at different stages of surgical intervention

Hookworm Infection and Environmental Factors in Mbeya Region, Tanzania: A Cross-sectional, Population-based study.

Hookworm disease is one of the most common infections and cause of a high disease burden in the tropics and subtropics. Remotely sensed ecological data and model-based geostatistics have been used recently to identify areas in need for hookworm control. Cross-sectional interview data and stool samples from 6,375 participants from nine different sites in Mbeya region, south-western Tanzania, were collected as part of a cohort study. Hookworm infection was assessed by microscopy of duplicate Kato-Katz thick smears from one stool sample from each participant. A geographic information system was used to obtain remotely sensed environmental data such as land surface temperature (LST), vegetation cover, rainfall, and elevation, and combine them with hookworm infection data and with socio-demographic and behavioral data. Uni- and multivariable logistic regression was performed on sites separately and on the pooled dataset. Univariable analyses yielded significant associations for all ecological variables. Five ecological variables stayed significant in the final multivariable model: population density (odds ratio (OR) = 0.68; 95% confidence interval (CI) = 0.63-0.73), mean annual vegetation density (OR = 0.11; 95% CI = 0.06-0.18), mean annual LST during the day (OR = 0.81; 95% CI = 0.75-0.88), mean annual LST during the night (OR = 1.54; 95% CI = 1.44-1.64), and latrine coverage in household surroundings (OR = 1.02; 95% CI = 1.01-1.04). Interaction terms revealed substantial differences in associations of hookworm infection with population density, mean annual enhanced vegetation index, and latrine coverage between the two sites with the highest prevalence of infection. This study supports previous findings that remotely sensed data such as vegetation indices, LST, and elevation are strongly associated with hookworm prevalence. However, the results indicate that the influence of environmental conditions can differ substantially within a relatively small geographic area. The use of large-scale associations as a predictive tool on smaller scales is therefore problematic and should be handled with care

IL-1α/IL-1R1 expression in chronic obstructive pulmonary disease and mechanistic relevance to smoke-induced neutrophilia in mice.

Cigarette smoking is the main risk factor for the development of chronic obstructive pulmonary disease (COPD), a major cause of morbidity and mortality worldwide. Despite this, the cellular and molecular mechanisms that contribute to COPD pathogenesis are still poorly understood