1000 resultados para Photodynamic action


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The fungicidal action of sodium hypochlorite (0.3, 1, 2.5, 5 and 10%); formaldehyde (2, 5, and 10%); and ethyl alcohol (70%) on yeast forms of Paracoccidioides brasiliensis Pb 18 and a newly-isolated Goiana strain was described. Contact between the fungus and the disinfectants was maintained for 1, 2, 24, 48 and 72 hours at room temperature. Viability was evaluated by the fluorescein diacetate-ethidium bromide treatment, culture in solid and liquid media (36ºC and 26ºC); yeast to mycelial germination at room temperature; and radiometric study of metabolic activity. All concentrations of disinfectants were found to be effective in inactivating Pb 18 and Goiana strains, except for the 1-hour contact with 2% formaldehyde, in which fluorescein diacetate-ethidium bromide treatment was found to reveal 40 and 27% of viable cells, respectively. The yeast to mycelial germination method was considered to reveal faster and similar results as compared to culture in solid and liquid media.

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Hydraulic systems are dynamically susceptible in the presence of entrapped air pockets, leading to amplified transient reactions. In order to model the dynamic action of an entrapped air pocket in a confined system, a heuristic mathematical formulation based on a conceptual analogy to a mechanical spring-damper system is proposed. The formulation is based on the polytropic relationship of an ideal gas and includes an additional term, which encompasses the combined damping effects associated with the thermodynamic deviations from the theoretical transformation, as well as those arising from the transient vorticity developed in both fluid domains (air and water). These effects represent the key factors that account for flow energy dissipation and pressure damping. Model validation was completed via numerical simulation of experimental measurements.

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Apresentação realizada no OH&S Forum 2011 - International Forum on Occupational Health and Safety: Policies, profiles and services, na Finlândia de, 20 a 22 Junho de 2011.

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Comunicação apresentada na 18th Conference International of Health Promotion Hospitals & Health Services "Tackling causes and consequences of inequalities in health: contributions of health services and the HPH network", em Manchester de 14-16 de april de 2010

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Summary form only given. Bacterial infections and the fight against them have been one of the major concerns of mankind since the dawn of time. During the `golden years' of antibiotic discovery, during the 1940-90s, it was thought that the war against infectious diseases had been won. However currently, due to the drug resistance increase, associated with the inefficiency of discovering new antibiotic classes, infectious diseases are again a major public health concern. A potential alternative to antibiotic treatments may be the antimicrobial photodynamic inactivation (PDI) therapy. To date no indication of antimicrobial PDI resistance development has been reported. However the PDI protocol depends on the bacteria species [1], and in some cases on the bacteria strains, for instance Staphylococcus aureus [2]. Therefore the development of PDI monitoring techniques for diverse bacteria strains is critical in pursuing further understanding of such promising alternative therapy. The present works aims to evaluate Fourier-Transformed-Infra-Red (FT-IR) spectroscopy to monitor the PDI of two model bacteria, a gram-negative (Escherichia coli) and a gram-positive (S. aureus) bacteria. For that a high-throughput FTIR spectroscopic method was implemented as generally described in Scholz et al. [3], using short incubation periods and microliter quantities of the incubation mixture containing the bacteria and the PDI-drug model the known bactericidal tetracationic porphyrin 5,10,15,20-tetrakis (4-N, N, Ntrimethylammoniumphenyl)-porphyrin p-tosylate (TTAP4+). In both bacteria models it was possible to detect, by FTIR-spectroscopy, the drugs effect on the cellular composition either directly on the spectra or on score plots of principal component analysis. Furthermore the technique enabled to infer the effect of PDI on the major cellular biomolecules and metabolic status, for example the turn-over metabolism. In summary bacteria PDI was monitored in an economic, rapid (in minutes- , high-throughput (using microplates with 96 wells) and highly sensitive mode resourcing to FTIR spectroscopy, which could serve has a technological basis for the evaluation of antimicrobial PDI therapies efficiency.

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The integrated numerical tool SWAMS (Simulation of Wave Action on Moored Ships) is used to simulate the behavior of a moored container carrier inside Sines’ Harbour. Wave, wind, currents, floating ship and moorings interaction is discussed. Several case scenarios are compared differing in the layout of the harbour and wind and wave conditions. The several harbour layouts correspond to proposed alternatives for the future expansion of Sines’ terminal XXI that include the extension of the East breakwater and of the quay. Additionally, the influence of wind on the behavior of the ship moored and the introduction of pre tensioning the mooring lines was analyzed. Hydrodynamic forces acting on the ship are determined using a modified version of the WAMIT model. This modified model utilizes the Haskind relations and the non-linear wave field inside the harbour obtained with finite element numerical model, BOUSS-WMH (Boussinesq Wave Model for Harbors) to get the wave forces on the ship. The time series of the moored ship motions and forces on moorings are obtained using BAS solver. © 2015 Taylor & Francis Group, London.

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Dissertation presented to obtain the Ph.D. degree in Biochemistry at the Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa

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ABSTRACT – Background: Primary Health Care (PHC) is usually the first contact with the health system, and health professionals are key mediators for enabling citizens to take care of their health. In Portugal, great improvements have been achieved in the biometric indicators of maternal and child health during the last decades. Nevertheless, scant attention has been paid to the mental health dimension, in spite of the recognition of its importance, being pregnancy and early childhood crucial opportunities in the lifecycle for mental health promotion, especially in the early years of life, with a strong impact in the health of the child. The impact of early attachment between mother and baby on maternal and child health has long been recognized. This attachment can be influenced by some factors, as the mother’s emotional adjustment. Attention to these factors may facilitate implementation of both positive conditions and preventative measures. Family support during the transition to parenthood has been highlighted as an effective measure and PHC professionals are in a privileged position as information sources as well as mediators. Aims: The project we present describes an action-research process developed together among academic researchers and health professionals to embrace these issues. We intend to enable health professionals to support families in the transition to parenthood thereby promoting children’s mental health. Approach: The project is driven by a participatory approach intended to lead to reorganization of health care during pregnancy and early childhood. Effective change happens when those involved are interested and motivated, what makes their participation so important. Reflection about current practices and needs, and knowledge about evidence-based interventions have been guiding the selection of changes to introduce in clinical practice for family support and development of parenthood skills and self-confidence. Development: We summarize the main steps in development: the initial assessment and the picture taken from the community under study; the decision making process; the training programme of PHC professionals in action; the review of the protocols of maternal consultation, home visits and antenatal education; the implementation planning; the plan for evaluation the effectiveness of the changes introduced in the delivery of maternal and child health care units. The already developed work has shown that motivation, leadership and organizational issues are decisive for process development.-------------------------- RESUMO - Os Cuidados de Saúde Primários são habitualmente o primeiro contacto com o sistema de saúde e os profissionais de saúde são mediadores chave na capacitação dos cidadãos para cuidarem da sua saúde. Em Portugal, nas últimas décadas, têm-se alcançado grandes melhorias nos indicadores biométricos de saúde materno-infantil. Contudo, tem-se dedicado pouca atenção à dimensão de saúde mental, apesar do reconhecimento da sua importância. A gravidez e primeira infância têm sido apontadas como uma oportunidade crucial no ciclo de vida para a promoção da saúde mental. É dado especial enfoque aos primeiros tempos de vida, dado o forte impacto na saúde da criança. O impacte da vinculação precoce entre a mãe e o bebé na saúde da mãe e da criança há muito que é reconhecido. Esta vinculação pode ser influenciada por vários factores, nomeadamente pelo ajustamento emocional da mãe. A focalização nestes aspectos pode facilitar a criação de condições favoráveis e a implementação de medidas preventivas. O suporte familiar durante o período de transição para a parentalidade tem sido enfatizado como uma medida eficaz e os Cuidados de Saúde Primários estão numa posição privilegiada como fontes de informação e como mediadores. O projecto que apresentamos descreve um processo de investigação- acção desenvolvido em parceria entre investigadores académicos e profissionais de saúde para abordar os aspectos referidos. Pretende-se capacitar os profissionais de saúde para apoiarem as famílias na transição para a parentalidade, promovendo assim a saúde mental das crianças. O projecto baseia-se numa abordagem participativa, direccionada para a reorganização dos cuidados durante a gravidez e primeiros tempos de vida. A mudança efectiva acontece quando os envolvidos estão interessados e motivados, o que torna a sua participação tão importante. A reflexão acerca das práticas e necessidades actuais e o conhecimento acerca de intervenções baseadas na evidência têm guiado a selecção das alterações a introduzir na prática clínica, no sentido de promover o suporte familiar e o desenvolvimento de competências parentais e auto-confiança. Neste artigo, apresentamos as etapas principais do desenvolvimento do projecto: avaliação inicial da comunidade em estudo; processo de tomada de decisão; programa de formação dos profissionais dos Cuidados de Saúde Primários; revisão dos protocolos da consulta de saúde materna, visita domiciliária e educação pré-natal; planeamento da implementação; plano de avaliação da efectividade das alterações introduzidas na prestação de cuidados. O trabalho já desenvolvido tem mostrado que a motivação, liderança e aspectos

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The interaction between specific immune response to Schistosoma mansoni and praziquantel (PZQ) was studied in mice. In mice harboring concomitant immunity, 6-day-old parasites treated with PZQ were more effectively removed than 24h treated parasites despite both had a significant worm burden reduction when compared with respective treated controls. These results show that PZQ can be effective at the skin and lung stages of parasite's development mainly acting with a established specific immune response, and particularly at the lung phase.

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The external forces applied in swimming starts have been often studied, but using direct analysis and simple interpretation data processes. This study aimed to develop a tool for vertical and horizontal force assessment based on the swimmers' propulsive and structural forces (passive forces due to dead weight) applied during the block phase. Four methodological pathways were followed: the experimented fall of a rigid body, the swimmers' inertia effect, the development of a mathematical model to describe the outcome of the rigid body fall and its generalization to include the effects of the inertia, and the experimental swimmers' starting protocol analysed with the inclusion of the developed mathematical tool. The first three methodological steps resulted in the description and computation of the passive force components. At the fourth step, six well-trained swimmers performed three 15 m maximal grab start trials and three-dimensional (3D) kinetic data were obtained using a six degrees of freedom force plate. The passive force contribution to the start performance obtained from the model was subtracted from the experimental force due to the swimmers resulting in the swimmers' active forces. As expected, the swimmers' vertical and horizontal active forces accounted for the maximum variability contribution of the experimental forces. It was found that the active force profile for the vertical and horizontal components resembled one another. These findings should be considered in clarifying the active swimmers' force variability and the respective geometrical profile as indicators to redefine steering strategies.

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SUMMARY The molluscicidal activity of the leaf powder of Moringa oleifera and lyophilized fruit powder of Momordica charantia against the snail Lymnaea acuminata was time and concentration dependent. M. oleifera leaf powder (96 h LC50: 197.59 ppm) was more toxic than M. charantia lyophilized fruit powder (96 h LC50: 318.29 ppm). The ethanolic extracts of M. oleifera leaf powder and Momordica charantia lyophilized fruit powder were more toxic than other organic solvent extracts. The 96 h LC50 of the column purified fraction of M. oleifera leaf powder was 22.52 ppm, while that of M. charantia lyophilized fruit powder was 6.21 ppm. Column, thin layer and high performance liquid chromatography analysis show that the active molluscicidal components in M. oleifera leaf powder and lyophilized fruit of M. charantia are benzylamine (96 h LC50: 2.3 ppm) and momordicine (96 h LC50: 1.2 ppm), respectively. Benzylamine and momordicine significantly inhibited, in vivo and in vitro, the acetylcholinesterase (AChE), acid and alkaline phosphatase (ACP/ALP) activities in the nervous tissues of L. acuminata. Inhibition of AChE, ACP and ALP activity in the nervous tissues of L. acuminata by benzylamine and momordicine may be responsible for the molluscicidal activity of M. oleifera and M. charantia fruits, respectively.

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SUMMARY In a previous study our group found that the probiotic Saccharomyces boulardii was capable of reducing the intensity of infection in mice with toxocariasis. In order to assess whether the mechanism involved would be a direct action of the probiotic on Toxocara canis larvae, this study was designed. Both probiotics were singly cultivated in plates containing RPMI 1640 medium and T. canis larvae. S. boulardii and B. cereus var. toyoi cultures presented 97.6% and 95.7% of larvae with positive motility, respectively, and absence of color by the dye trypan blue, not representing significant difference to the control group (p > 0.05). We conclude that none of the probiotics showed in vitro effects on T. canis larvae and that the interaction with the intestinal mucosa is necessary for the development of the protective effect of S. boulardii.

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Introduction & Objectives: Several factors may influence the decision to pursue nonsurgical modalities for the treatment of non-melanoma skin cancer. Topical photodynamic therapy (PDT) is a non-invasive alternative treatment reported to have a high efficacy when using standardized protocols in Bowen’s disease (BD), superficial basal cell carcinoma (BCC) and in thin nodular BCC. However, long-term recurrence studies are lacking. The aim of this study was to evaluate the long-term efficacy of PDT with topical methylaminolevulinate (MAL) for the treatment of BD and BCC in a dermato-oncology department. Materials & Methods: All patients with the diagnosis of BD or BCC, treated with MAL-PDT from the years 2004 to 2008, were enrolled. Treatment protocol included two MAL-PDT sessions one week apart repeated at three months when incomplete response, using a red light dose of 37-40 J/cm2 and an exposure time of 8’20’’. Clinical records were retrospectively reviewed, and data regarding age, sex, tumour location, size, treatment outcomes and recurrence were registered. Descriptive analysis was performed using chi square tests, followed by survival analysis with the Kaplan-Meier and Cox regression models. Results: Sixty-eight patients (median age 71.0 years, P25;P75=30;92) with a total of 78 tumours (31 BD, 45 superficial BCC, 2 nodular BCC) and a median tumour size of 5 cm2 were treated. Overall, the median follow-up period was 43.5 months (P25;P75=0;100), and a total recurrence rate of 33.8% was observed (24.4 % for BCC vs. 45.2% for BD). Estimated recurrence rates for BCC and BD were 5.0% vs. 7.4% at 6 months, 23.4% vs. 27.9% at 12 months, and 30.0% vs. 72.4% at 60 months. Both age and diagnosis were independent prognostic factors for recurrence, with significantly higher estimated recurrence rates in patients with BD (p=0.0036) or younger than 58 years old (p=0.039). The risk of recurrence (hazard ratio) was 2.4 times higher in patients with BD compared to superficial BCC (95% CI:1.1-5.3; p=0.033), and 2.8 times higher in patients younger than 58 years old (95% CI:1.2-6.5; p=0.02). Conclusions: In the studied population, estimated recurrence rates are higher than those expected from available literature, possibly due to a longer follow-up period. To the authors’ knowledge there is only one other study with a similar follow-up period, regarding BCC solely. BD, as an in situ squamous cell carcinoma, has a higher tendency to recur than superficial BCC. Despite greater cosmesis, PDT might no be the best treatment option for young patients considering their higher risk of recurrence.

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Anogenital lichen sclerosus is a chronic, inflammatory, mucocutaneous disorder of significant morbidity. Common symptoms include pruritus, pain, dysuria, and dyspareunia, frequently of difficult control. Photodynamic therapy (PDT) may be an effective therapeutic option in selected cases refractory to first--‐line treatment options. However, procedure--‐related pain is a limiting factor in patient adherence to treatment. Conscious sedation and analgesia with a ready--‐to--‐use gas mixture of nitrous oxide and oxygen is useful in short--‐term procedures. It provides a rapid, effective, and short--‐lived effect, without the need for anesthesiology support. A 75--‐year--‐old woman presented with a highly symptomatic, histologically confirmed vulvar lichen sclerosus, with at least 15 years of evolution. Pain, pruritus, and dysuria were intense and disabling. Treatment with ultrapotent topical corticosteroids proved to be ineffective despite patient compliance. She was then referred for PDT. A total of 3 sessions were performed, held at a mean interval of 9 weeks, and under the analgesic and sedative effect of nitrous oxide/oxygen gas. Response to treatment was evaluated through a daily, self--‐reported pain rating scale. Dysuria remitted completely after the first PDT session. An 80% reduction in pruritus and pain was observed after the third session, and has been sustained for the past six months without further need for topical corticotherapy. Treatment sessions were well tolerated and pain-- free, with no side effects to report. PDT appears to be effective in the symptomatic treatment of vulvar lichen sclerosus. To the authors’ knowledge this is the first case reporting the use of inhaled nitrous oxide/oxygen gas mixture during PDT performed in the genital area. Its analgesic and sedative effects may increase patients’ adherence to this painful procedure. Furthermore, given its safety, it can be easily managed in outpatient clinics by trained dermatologists.