Quality of life in dilated cardiomyopathy with refractory chronic heart failure undergoing devices implantation

Heart failure is the final stage of most of cardiac diseases. It is a complex syndrome in which the patients should have the following features: symptoms of heart failure, typically shortness of breath at rest or during exertion, and/or fatigue; signs of fluid retention such as pulmonary congestion or ankle swelling; and objective evidence of an abnormality of the structure or function of the heart at rest. This progressive syndrome as a high incidence and prevalence and poor prognosis: four-year mortality is around 50% with 40% of the patients admitted to hospital dying or readmitted within a year. With ageing, many patients will develop chronic heart failure, which, because of its symptoms, patient’s awareness of their risk of dying, and the effects of therapy, together with frequent hospitalizations, has considerable impact on patient’s health-related quality of life.

Placas de OSB: investigação e estudo laboratorial das suas características de desempenho

A utilização de placas de OSB – Oriented Strand Board está em franca expansão no território nacional e parece ser uma alternativa ecológica e económica aos painéis de derivados de madeira normalmente usados. O OSB é obtido num processo de fabrico resultante da interacção de diversas variáveis, que conferem aos painéis uma vasta gama de aplicações estruturais ou não estruturais (paredes exteriores e interiores, pavimentos, coberturas, componentes de vigas, cofragens, embalagens, móveis, elementos de decoração, etc.). Neste trabalho pretendeu-se investigar, através de pesquisa bibliográfica as características das placas OSB assim como seu processo de fabrico e condicionantes existentes no seu decurso. Em seguida estas foram comparadas com os seus principais concorrentes, o contraplacado e o aglomerado de madeira e cimento. O trabalho experimental realizado teve como objectivo analisar as propriedades de OSB, proveniente do mercado nacional, de acordo com a EN 300:2006 e com os dados recolhidos na pesquisa bibliográfica. Foram executados ensaios de flexão (EN 310:2002), inchamento em espessura (EN 317:2002) e ensaios de flexão após envelhecimento (EN 321:2010). Concluiu-se que o OSB é um material com algumas características de destaque, no entanto a substituição de outros derivados de madeira por este deve ser acompanhada por estudos, principalmente em ambientes húmidos. É importante realçar que este possui modelos com características específicas para determinadas utilizações e ambientes que possibilitam uma optimização do seu comportamento, no entanto, nos ensaios realizados apenas foi utilizado um modelo base de OSB.

Estudo de caso

História Clínica: Um paciente com história de diversas lesões nos membros inferiores foi intervencionado em ambos os pés, onde realizou uma tenossinovectomia dos peroneais com reparação de ruptura desses tendões (ao pé direito em 2006 sendo actualmente ao esquerdo). Avaliação Objectiva: Apresentava dor, edema, limitação articular de todos os movimentos da tibio-társica, fraqueza muscular, pés cavos e alterações do padrão de marcha e do equilíbrio. Objectivo: foi verificar se a mobilização com movimento (MWM) do astrágalo e da articulação tibio-peroneal inferior levava a uma diminuição da dor e aumentava a amplitude de dorsiflexão e inversão neste doente com pé cavo. Intervenção: foi realizada MWM do astrágalo e do perónio na articulação tibioperoneal inferior em descarga e em semi-carga, sendo mantida essa nova posição com uma ligadura de tape. Resultados: o paciente aumentou as amplitudes articulares em descarga e em carga, diminuiu o edema da perna e pé, aumentou a funcionalidade, mas em termos de força muscular não foram quantificadas alterações. Conclusão: mesmo o paciente tendo pé cavo e sequelas de uma tenossinovectomia dos peroneais, as manobras de mobilização com movimento do astrágalo e da articulação tíbio-peroneal inferior levaram a uma eliminação da dor e a um aumento da amplitude articular.

Influence of environmental temperature and humidity on the acute ventilatory response to exercise in asthmatic adolescents

Asthma is a chronic inflammatory disorder of the respiratory airways affecting people of all ages, and constitutes a serious public health problem worldwide (6). Such a chronic inflammation is invariably associated with injury and repair of the bronchial epithelium known as remodelling (11). Inflammation, remodelling, and altered neural control of the airways are responsible for both recurrent exacerbations of asthma and increasingly permanent airflow obstruction (11, 29, 34). Excessive airway narrowing is caused by altered smooth muscle behaviour, in close interaction with swelling of the airway walls, parenchyma retractile forces, and enhanced intraluminal secretions (29, 38). All these functional and structural changes are associated with the characteristic symptoms of asthma – cough, chest tightness, and wheezing –and have a significant impact on patients’ daily lives, on their families and also on society (1, 24, 29). Recent epidemiological studies show an increase in the prevalence of asthma, mainly in industrial countries (12, 25, 37). The reasons for this increase may depend on host factors (e.g., genetic disposition) or on environmental factors like air pollution or contact with allergens (6, 22, 29). Physical exercise is probably the most common trigger for brief episodes of symptoms, and is assumed to induce airflow limitations in most asthmatic children and young adults (16, 24, 29, 33). Exercise-induced asthma (EIA) is defined as an intermittent narrowing of the airways, generally associated with respiratory symptoms (chest tightness, cough, wheezing and dyspnoea), occurring after 3 to 10 minutes of vigorous exercise with a maximal severity during 5 to 15 minutes after the end of the exercise (9, 14, 16, 24, 33). The definitive diagnosis of EIA is confirmed by the measurement of pre- and post-exercise expiratory flows documenting either a 15% fall in the forced expiratory volume in 1 second (FEV1), or a ≥15 to 20% fall in peak expiratory flow (PEF) (9, 24, 29). Some types of physical exercise have been associated with the occurrence of bronchial symptoms and asthma (5, 15, 17). For instance, demanding activities such as basketball or soccer could cause more severe attacks than less vigorous ones such as baseball or jogging (33). The mechanisms of exercise-induced airflow limitations seem to be related to changes in the respiratory mucosa induced by hyperventilation (9, 29). The heat loss from the airways during exercise, and possibly its post-exercise rewarming may contribute to the exercise-induced bronchoconstriction (EIB) (27). Additionally, the concomitant dehydration from the respiratory mucosa during exercise leads to an increased interstitial osmolarity, which may also contribute to bronchoconstriction (4, 36). So, the risk of EIB in asthmatically predisposed subjects seems to be higher with greater ventilation rates and the cooler and drier the inspired air is (23). The incidence of EIA in physically demanding coldweather sports like competitive figure skating and ice hockey has been found to occur in up to 30 to 35% of the participants (32). In contrast, swimming is often recommended to asthmatic individuals, because it improves the functionality of respiratory muscles and, moreover, it seems to have a concomitant beneficial effect on the prevalence of asthma exacerbations (14, 26), supporting the idea that the risk of EIB would be smaller in warm and humid environments. This topic, however, remains controversial since the chlorified water of swimming pools has been suspected as a potential trigger factor for some asthmatic patients (7, 8, 20, 21). In fact, the higher asthma incidence observed in industrialised countries has recently been linked to the exposition to chloride (7, 8, 30). Although clinical and epidemiological data suggest an influence of humidity and temperature of the inspired air on the bronchial response of asthmatic subjects during exercise, some of those studies did not accurately control the intensity of the exercise (2, 13), raising speculation of whether the experienced exercise overload was comparable for all subjects. Additionally, most of the studies did not include a control group (2, 10, 19, 39), which may lead to doubts about whether asthma per se has conditioned the observed results. Moreover, since the main targeted age group of these studies has been adults (10, 19, 39), any extrapolation to childhood/adolescence might be questionable regarding the different lung maturation. Considering the higher incidence of asthma in youngsters (30) and the fact that only the works of Amirav and coworkers (2, 3) have focused on this age group, a scarcity of scientific data can be identified. Additionally, since the main environmental trigger factors, i.e., temperature and humidity, were tested separately (10, 28, 39) it would be useful to analyse these two variables simultaneously because of their synergic effect on water and heat loss by the airways (31, 33). It also appears important to estimate the airway responsiveness to exercise within moderate environmental ranges of temperature and humidity, trying to avoid extreme temperatures and humidity conditions used by others (2, 3). So, the aim of this study was to analyse the influence of moderate changes in air temperature and humidity simultaneously on the acute ventilatory response to exercise in asthmatic children. To overcome the above referred to methodological limitations, we used a 15 minute progressive exercise trial on a cycle ergometer at 3 different workload intensities, and we collected data related to heart rate, respiratory quotient, minute ventilation and oxygen uptake in order to ensure that physiological exercise repercussions were the same in both environments. The tests were done in a “normal” climatic environment (in a gymnasium) and in a hot and humid environment (swimming pool); for the latter, direct chloride exposition was avoided.

Influence of the pre-treatments on the properties of biodegradable films from bovine hair

The replacement of conventional synthetic films and coatings by biodegradable alternatives reduces the use of non-renewable resources and waste disposal problems. Considering that Portugal is a major producer of leather, and consequently a large producer of related wastes, in this research, bovine hair was tested for the production of biodegradable films directly by thermo-compression, allowing waste valorisation and reduction of environmental pollution. The aim of this study was to determine the influence of the different pre-treatments performed by two processes (removal by mechanical action and removal by chemical process), applied to bovine hair, in order to obtain a biodegradable film with appropriate properties. Mechanical properties for these films were evaluated, namely strain at break, stress at break and Young modulus. Additionally colour, solubility and swelling in water were also studied. The mechanical removal hair only produced films with Na2S treatment. Chemical removed hair (immunization) depends of the pre-treatment and the degreasing with petroleum ether or sodium sulphide pre-treatment leads better mechanical properties. The results obtained indicated that the pre-treatments have an important role in the final properties of biodegradable films.

First Curl, Then Wrinkle

The excellent properties of elastomers are exploited to trigger wrinkling instabilities in curved shells. Micro- and nano-fibres are produced by electrospinning and UV irradiated: each fibre consists of a soft core and a stiff outer half-shell. Upon solvent de-swelling, the fibres curl because the shell and the core have different natural lengths. Wrinkling only starts after the fibre has attained a well-defined helical shape. A simple analytical model is proposed to find the curling curvature and wrinkle wavelength, as well as the transition between the “curling” and “wrinkling” regimes. This new instability resembles that found in the tendrils of climbing plants as they dry and lignify.

Observação e controlo da segurança estrutural de barragens de betão: utilização integrada de modelos numéricos e de modelos de separação de efeitos

Dissertação de Natureza Científica elabora da no âmbito do protocolo de cooperação entre o ISEL e o LNEC para obtenção do grau de Mestre em Engenharia Civil

Development of Chitosan and Poly (Vinyl Alcohol) Blended scaffolds for cell culture using supercritical fluids technology

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Mestrado Integrado em Engenharia Química e Bioquímica

Hierarchical wrinkling on elastometric Janus spheres

Hierarchical wrinkling on elastomeric Janus spheres is permanently imprinted by swelling, for different lengths of time, followed by drying the particles in an appropriate solvent. First-order buckling with a spatial periodicity (lambda(11)) of the order of a few microns and hierarchical structures comprising of 2nd order buckling with a spatial periodicity (lambda(12)) of the order of hundreds of nanometers have been obtained. The 2nd order buckling features result from a Grinfeld surface instability due to the diffusion of the solvent and the presence of sol molecules.

Couro pergaminho e couro transparente: desenvolvimento de processo

Mestrado em Engenharia Química - Ramo Optimização Energética na Indústria Química

Cyclophosphamide effect on coccidioidomycosis in the rat

Coccidioidomycosis is a systemic mycosis, endemic in arid areas of the American continent. The rat was employed as an experimental host, since it had been shown to reproduce human lesions and present a chronic course of disease with granulomas mainly restricted to lungs. Given the influence of immunosuppressive therapy on the clinical course of human coccidioidomycosis, we studied the effect of cyclophosphamide (CY) in the experimental rat model. Accordingly, animals were inoculated with 400 Coccidioides immitis arthroconidia of the Acosta strain, by intracardiacal route. As single CY doses failed to alter the course of disease, three schedules were used: A) 4 daily doses of 20 mg/kg each, prior to C. immitis inoculation; B) 4 similar daily doses after infection; and C); 6 doses of 20 mg/kg each, given from day +1 to +4, then on days +8 and +9, post infection (pi), taking day 0 as the time of fungal inoculation. The first two schedules inhibited antibody formation up to day 28 pi, without modifying cellular response to coccidioidin as measured by foodpad swelling. Initially, there was greater fungal spread than in controls receiving C. immitis alone, which proved self-limiting in the latter. In contrast, schedule C led to 559r mortality, with both humoral and cellular response abrogation, accompanied by extensive C. immitis dissemination. Histology disclosed significant alterations, such as the persistence of primary infection sporangia, corresponding to the acute stage of coccidioidomycosis in the absence of granuloma development. Therefore, the observed depression in cellular immunity seems responsible for the lack of inflammatory reaction capable of restricting sporangia proliferation in tissues which, in turn, enhances pathogen spread and mortality rate.

Experimental coccidioidomycosis in the immunosuppressed rat

C. immitis inoculated rats are known to develop infection restricted to lung whereas cyclophosphamide (CY) treatment leads to widespread dissemination with considerable mortality. In this study, an attempt was made to elucidate the mechanisms involved in such behaviour. With this aim, spleen cells were transferred from infected CY-treated to infected untreated rats, achieving significant specific inhibition in footpad swelling to coccidioidin in recipients, attributable to a suppressor T cell subpopulation induced by greater fungal antigen concentration arising from widespread C. immitis dissemination in immunosuppressed animals. NK activity proved similar regardless of CY treatment. Lastly, chronically infected rats presented increased colony forming units count after several weekly doses of CY, as happens in immunosuppressed patients harbouring a previous infection.

Non-venomous snake bite and snake bite without envenoming in a brazilian teaching hospital: analysis of 91 cases

A retrospective survey of 473 cases of snake bite admitted to a Brazilian teaching hospital from 1984 to 1990 revealed 91 cases of bite without envenoming and/or caused by non-venomous snakes. In 17 of these cases the snake was identified, and one patient was bitten by a snake-like reptile (Amphisbaena mertensii). In 43 cases diagnosis was made on clinical grounds (fang marks in the absence of signs of envenoming). The other 30 cases were of patients who complained of being bitten but who did not show any sign of envenoming or fang mark. Most cases occurred in men (66;73%), in the 10-19 years age group (26;29%), in the lower limbs (51/74;69%), between 6 A. M. and 2 P.M. (49;61%) and in the month of April (16; 18%). One patient bitten by Philodryas olfersii developed severe local pain, swelling and redness at the site of the bite, with normal clotting time. The patient bitten by Drymarcon corais was misdiagnosed as being bitten by a snake of the genus Bothrops, was given the specific antivenom, and developed anaphylaxis. One patient bitten by Sibynomorphus mikanii presented prolonged clotting time, and was also given antivenom as a case of Bothrops bite. Correct identification of venomous snakes by physicians is necessary to provide correct treatment to victims of snake bite, avoiding unnecessary distress to the patient, and overprescription of antivenom, which may eventually cause severe untoward effects.

Lance-headed viper (Bothrops moojeni) bite wounding the eye

A 5-year-old girl was bitten in her left eye by a lance-headed viper identified as Bothrops moojeni, measuring 115 cm of length. There was severe facial swelling and left exophthalmus, and enucleation of the eye was necessary. The patient apparently had mild systemic envenoming, but local inflammatory signs and histological evidence of necrosis suggest that both the mechanical trauma and the local action of the venom had a role in the genesis of the eye lesion. It is arguable if the loss of the eye could be prevented even if the antivenom was administered earlier.

Philodryas patagoniensis bite and local envenoming

A 5-year-old boy bitten by a specimen of Philodryas patagoniensis, a colubrid snake currently classified as nonvenomous, developed signs of local envenoming characterized by swelling and warmth on the bitten limb. This is the first time that local envenoming following Philodryas patagoniensis bite is recognized. Based on the clinical findings and misidentification of the snake, the patient was treated as a victim of Bothrops bite, having received unnecessarily the specific antivenom. Educational efforts to make doctors and health workers capable to identify correctly venomous snakes are necessary, to avoid inappropriate indication of antivenom and decrease the risk of its potentially harmful untoward effects. Examination of the bite site can be useful to the differential diagnosis between pit viper and colubrid bites.