Avaliação da força de preensão da mão, força dos membros inferiores e capacidade funcional em idosos activos e sedentários

Introdução: A prática de exercício físico regular tem impacto na melhoria da aptidão física global dos idosos. Objectivos: O objectivo deste estudo descritivo foi analisar se a prática de exercício físico regular influencia a força de preensão global da mão, a força dos membros inferiores e a capacidade funcional em indivíduos residentes no concelho de Loures, com idade superior a 60 anos de idade. Metodologia: Através de um questionário de caracterização da população foi seleccionada, uma amostra de 60 indivíduos habitantes do concelho de Loures (de idades entre 60 e 91 anos), dos quais 30 praticam exercício físico regular e 30 não praticam qualquer tipo de exercício físico. A força de preensão da mão foi avaliada através de um dinamómetro portátil, a força dos membros inferiores através do teste de sentar e levantar da cadeira (TSLC), a capacidade funcional através do teste de 6 minutos de marcha (T6MM) e a percepção subjectiva de esforço (RPE), segundo a escala de Borg. Resultados: Para esta amostra concluiu-se que a prática regular de actividade física influencia o Peak Force (PF) da mão direita (p=0,037), o PF da mão esquerda (p=0,022), a Endurance (ED) da mão esquerda (p=0,017), o número de execuções correctas no TSLC (p=0,00), a distância total percorrida no T6MM (p=0,00) e a RPE durante o T6MM (p=0,00). O Time to Peak (TTP) da mão direita e esquerda (p=0,574 e 0,630, respectivamente) não apresentam diferenças significativas entre os grupos, bem como a ED da mão direita (p=0,219). Conclusão: poderá concluir-se que a prática de exercício físico, nesta amostra, contribui para uma melhor aptidão física que permite uma maior performance a nível da capacidade funcional e da força com menores índices de fadigabilidade.

Dimensionless analysis of constrained damping treatments

One of the most effective ways of controlling vibrations in plate or beam structures is by means of constrained viscoelastic damping treatments. Contrary to the unconstrained configuration, the design of constrained and integrated layer damping treatments is multifaceted because the thickness of the viscoelastic layer acts distinctly on the two main counterparts of the strain energy the volume of viscoelastic material and the shear strain field. In this work, a parametric study is performed exploring the effect that the design parameters, namely the thickness/length ratio, constraining layer thickness, material modulus, natural mode and boundary conditions have on these two counterparts and subsequently, on the treatment efficiency. This paper presents five parametric studies, namely, the thickness/length ratio, the constraining layer thickness, material properties, natural mode and boundary conditions. The results obtained evidence an interesting effect when dealing with very thin viscoelastic layers that contradicts the standard treatment efficiency vs. layer thickness relation; hence, the potential optimisation of constrained and integrated viscoelastic treatments through the use of properly designed thin multilayer configurations is justified. This work presents a dimensionless analysis and provides useful general guidelines for the efficient design of constrained and integrated damping treatments based on single or multi-layer configurations. (C) 2012 Elsevier Ltd. All rights reserved.

Size-segregated chemical composition of aerosol emissions in an urban road tunnel in Portugal

An atmospheric aerosol study was performed in 2008 inside an urban road tunnel, in Lisbon, Portugal. Using a high volume impactor, the aerosol was collected into four size fractions (PM0.5, PM0.5-1, PM1-2.5 and PM2.5-10) and analysed for particle mass (PM), organic and elemental carbon (OC and EC), polycyclic aromatic hydrocarbons (PAH), soluble inorganic ions and elemental composition. Three main groups of compounds were discriminated in the tunnel aerosol: carbonaceous, soil component and vehicle mechanical wear. Measurements indicate that Cu can be a good tracer for wear emissions of road traffic. Cu levels correlate strongly with Fe, Mn, Sn and Cr, showing a highly linear constant ratio in all size ranges, suggesting a unique origin through sizes. Ratios of Cu with other elements can be used to source apportion the trace elements present in urban atmospheres, mainly on what concerns coarse aerosol particles. (C) 2013 Elsevier Ltd. All rights reserved.

Complicações músculo-esqueléticas crónicas nas mulheres sobreviventes de cancro da mama

As mulheres com cancro da mama obtiveram, nos últimos anos, um aumento significativo da esperança média de vida; contudo, muitas destas mulheres vivem com as complicações crónicas resultantes do tratamento. O objetivo deste estudo é caracterizar as complicações músculo-esqueléticas (CME) nas sobreviventes de cancro da mama e enfatizar a necessidade de desenvolver terapêuticas preventivas para estas complicações. Métodos – Noventa e quatro mulheres sobreviventes de cancro da mama responderam a um questionário sobre potenciais CME. Resultados – Foi detetada associação significativa entre idade e linfedema (p=0,004), dor no braço (DB) (p=0,000), dor no ombro (DO) (p=0,004), dificuldade em elevar o braço (DEB) (p=0,022) e cervicalgia (p=0,000), verificando-se uma maior incidência nas mulheres com mais de 50 anos. Uma associação significativa foi detetada entre linfadenectomia e linfedema (p=0,000), DB (p=0,000), DO (p=0,008), verificando-se que as mulheres sujeitas a linfadenectomia apresentam maior incidência de linfedema, de DB e de DO. Quanto à sobrevivência constatou-se que as mulheres com mais de 10 anos de sobrevivência têm mais CME. Relativamente à mastectomia foi detetada associação significativa com o linfedema (p=0,012), DB (p=0,020), DO (p=0,003), DEB (p=0,037) e cervicalgia (p=0,020). Verificou-se que as mulheres mastectomizadas têm maior tendência para apresentar linfedema, DB, DO, DEB e cervicalgia. Conclusão – No nosso estudo, as mulheres acima dos 50 anos, as que realizaram a linfadenectomia, as com mais de 10 anos de sobrevivência e as mastectomizadas apresentaram maior incidência de CME.

Insulin resistance does not play a major role in lipid and apolipoprotein profile in obese women

Background: Obesity is associated with increased atherogenesis through alterations in lipids, among other potential factors. Some of those abnormalities might be mediated by insulin resistance (IR). Aims: To compare lipid and apolipoprotein profile between lean and obese women; to evaluate the influence of IR on lipid and apolipoprotein profile, in obese women. Methods: We studied 112 obese and 100 normal-weight premenopausal women without known cardiovascular disease. Both groups were characterized for anthropometrics and a fasting blood sample was collected for assessment of glucose, insulin, triglycerides, cholesterol (total, LDL and HDL), and apolipoproteins A-I, A-II, B, C-II, C-III, and E; IR was assessed by the homeostatic model assessment (HOMA-IR). We compared lipids between obese and lean women; we looked for correlation of those levels with anthropometrics and IR (independently from anthropometrics) in obese women. Results: Obese women were characterized by mean age=34.6±8.3 years, BMI=43.6±7.9 kg/m2, waist circumference (Wc)=117.5±15.1 cm, and HOMA-IR=4.28±3.5. Lean women (age=34.2±8.3 years, BMI=21.4±1.7 kg/m2, Wc=71.7±5.8 cm, and HOMA-IR=1.21±0.76) presented with significantly lower levels of total cholesterol (P=0.001), LDL-cholesterol (P<0.001), and triglycerides (P<0.001); they presented higher levels of HDL-cholesterol (P<0.001), Apo A-I (P<0.001) and Apo A-II (P=0.037). HOMA-IR showed no significant association with apolipoproteins. HOMA-IR was inversely associated with HDL-cholesterol (P=0.048; r=−0.187) but that association disappeared when we adjusted for waist circumference. Only triglycerides were directly associated with HOMA-IR (P<0.001; r=0.343) independently from anthropometrics. Conclusion: We confirm that obese women present worst lipid and apolipoprotein profile. However, with the exception for triglycerides, insulin resistance per se does not play a major role in lipid and apolipoprotein abnormalities observed in obese women.

Production, purification and characterisation of polysaccharides from pleurotus ostreatus with antitumor activity

Background: Mushroom polysaccharides play an important role in functional foods because they exhibit biological modulator properties such as antitumour, antiviral and antibacterial activities. The present study involved the production, purification and characterisation of intracellular and extracellular free and protein-bound polysaccharides from Pleurotus ostreatus and the investigation of their growth-inhibitory effect on human carcinoma cell lines. Results: Several fermentation parameters were obtained: batch polysaccharide productivities of 0.013 +/- 8.12 x 10-5 and 0.037 +/- 0.0005 g L-1 day-1 for intracellular and extracellular polysaccharides respectively, a maximum biomass concentration of 9.35 +/- 0.18 g L-1, Pmax = 0.935 +/- 0.018 g L-1 day-1, µmax = 0.218 +/- 0.02 day-1, YEP/X = 0.040 +/- 0.0015 g g-1 and YIP/X = 0.014 +/- 0.0003 g g-1. Some polysaccharides exhibited superoxide dismutase (SOD)-like activity of 50-200 units. Fourier transform infrared analysis of the polysaccharides revealed absorption bands characteristic of such biological macromolecules. Cytotoxicity assays showed that both intracellular and extracellular polysaccharides exhibited antitumour activity towards several tested human carcinoma cell lines in a dose-dependent manner. Conclusion - The polysaccharides of P. ostreatus exhibited high SOD-like activity, which strongly supports their biological effect on tumour cell lines. The extracellular polysaccharides presented the highest antitumour activity towards the RL95 carcinoma cell line and should be further investigated as an antitumour agent.

Non-enzymatic assay for glucose by using immobilized whole-cells of E. coli containing glucose binding protein fused to fluorescent proteins

Glucose monitoring in vivo is a crucial issue for gaining new understanding of diabetes. Glucose binding protein (GBP) fused to two fluorescent indicator proteins (FLIP) was used in the present study such as FLIP-glu- 3.2 mM. Recombinant Escherichia coli whole-cells containing genetically encoded nanosensors as well as cell-free extracts were immobilized either on inner epidermis of onion bulb scale or on 96-well microtiter plates in the presence of glutaraldehyde. Glucose monitoring was carried out by Förster Resonance Energy Transfer (FRET) analysis due the cyano and yellow fluorescent proteins (ECFP and EYFP) immobilized in both these supports. The recovery of these immobilized FLIP nanosensors compared with the free whole-cells and cell-free extract was in the range of 50–90%. Moreover, the data revealed that these FLIP nanosensors can be immobilized in such solid supports with retention of their biological activity. Glucose assay was devised by FRET analysis by using these nanosensors in real samples which detected glucose in the linear range of 0–24 mM with a limit of detection of 0.11 mM glucose. On the other hand, storage and operational stability studies revealed that they are very stable and can be re-used several times (i.e. at least 20 times) without any significant loss of FRET signal. To author's knowledge, this is the first report on the use of such immobilization supports for whole-cells and cell-free extract containing FLIP nanosensor for glucose assay. On the other hand, this is a novel and cheap high throughput method for glucose assay.