Assessment of oltipraz in schistosomiasis mansoni clinical trial

Seventy three children (6-15 years) and 75 adults (18-47 years) with active schistosomiasis mansoni were treated with oltipraz. All cases had at least 100 eggs per gram of feces as determined by the Kato-Katz technique. Children and adults were divided in two groups receiving respectively 25 or 30 mg/kg, as a single oral dose. Clinical examination, laboratories tests (haemogram, urinalysis, hepatic and kidney functions tests, glycemia, cholesterol, triglicerides, lipoprotein — HLD and LDL) and ECG were performed before, 3 or 7 days and 1 month after treatment. Parasitological control with 3 daily coprological examinations, was done on the 1st, 3rd j 6th month after drug administration. Giddiness, somnolence, headache, nausea, vomiting and abdominal distress were the most frequent side effects. Pain in the finger tips that need further investigations also occurred. No significant alteration in complementary tests were observed, whereas eosinophilia 1 month after treatment was detected, probably indicating worm death. The cure rate in children was 81.8% and 74.2% with 25 and 30 mg/kg respectively, and in adults 75.0% and 81.2% of the patients. No statistical significant difference was observed between cure rate and side effects at different dosages employed, neither between adults nor children. In all groups the percentage of egg reduction in feces in the non cured patients was higher than 96.0%. Further investigation with this new compound is necessary to accomplish the real value of oltipraz in the schistosomiasis chemotherapy.

Virtual Communities of Practice: Design and Development of Support Platforms and Participation Fostering

Mestrado em Engenharia Informática - Área de Especialização em Sistemas Gráficos e Multimédia

Segurança Alimentar no Quotidiano das Famílias Amarantinas

Dissertação de Mestrado em Gestão Integrada da Qualidade, Ambiente e Segurança

Desenvolvimento de um método potenciométrico para deteção de salmonella typhimurium

A Salmonella é um microrganismo responsável por grande parte das doenças alimentares, podendo por em causa a saúde pública da área contaminada. Uma deteção rápida, eficiente e altamente sensível e extremamente importante, sendo um campo em franco desenvolvimento e alvo de variados e múltiplos estudos na comunidade cientifica atual. Foi desenvolvido um método potenciométrico para a deteção de Salmonellas, com elétrodos seletivos de iões, construídos em laboratório com pontas de micropipetas, fios de prata e sensores com composição otimizada. O elétrodo indicador escolhido foi um ESI seletivo a cadmio, para redução da probabilidade de interferências no método, devido a pouca abundancia do cadmio em amostras alimentares. Elétrodos seletivos a sódio, elétrodos de Ag/AgCl de simples e de dupla juncão foram também construídos e caracterizados para serem aplicados como elétrodos de referência. Adicionalmente otimizaram-se as condições operacionais para a analise potenciométrica, nomeadamente o elétrodo de referencia utilizado, condicionamento dos elétrodos, efeito do pH e volume da solução amostra. A capacidade de realizar leituras em volumes muito pequenos com limites de deteção na ordem dos micromolares por parte dos ESI de membrana polimérica, foi integrada num ensaio com um formato nao competitivo ELISA tipo sanduiche, utilizando um anticorpo primário ligado a nanopartículas de Fe@Au, permitindo a separação dos complexos anticorpo-antigénio formados dos restantes componentes em cada etapa do ensaio, pela simples aplicação de um campo magnético. O anticorpo secundário foi marcado com nanocristais de CdS, que são bastante estáveis e é fácil a transformação em Cd2+ livre, permitindo a leitura potenciométrica. Foram testadas várias concentrações de peroxido de hidrogénio e o efeito da luz para otimizar a dissolução de CdS. O método desenvolvido permitiu traçar curvas de calibração com soluções de Salmonellas incubadas em PBS (pH 4,4) em que o limite de deteção foi de 1100 CFU/mL e de 20 CFU/mL, utilizando volumes de amostra de 10 ƒÊL e 100 ƒÊL, respetivamente para o intervalo de linearidade de 10 a 108 CFU/mL. O método foi aplicado a uma amostra de leite bovino. A taxa de recuperação media obtida foi de 93,7% } 2,8 (media } desvio padrão), tendo em conta dois ensaios de recuperação efetuados (com duas replicas cada), utilizando um volume de amostra de 100 ƒÊL e concentrações de 100 e 1000 CFU/mL de Salmonella incubada.

Novel Prostate Specific Antigen plastic antibody designed withcharged binding sites for an improved protein binding and itsapplication in a biosensor of potentiometric transduction

This work shows that the synthesis of protein plastic antibodies tailored with selected charged monomersaround the binding site enhances protein binding. These charged receptor sites are placed over a neutralpolymeric matrix, thus inducing a suitable orientation the protein reception to its site. This is confirmed bypreparing control materials with neutral monomers and also with non-imprinted template. This concepthas been applied here to Prostate Specific Antigen (PSA), the protein of choice for screening prostate can-cer throughout the population, with serum levels >10 ng/mL pointing out a high probability of associatedcancer.Protein Imprinted Materials with charged binding sites (C/PIM) have been produced by surfaceimprinting over graphene layers to which the protein was first covalently attached. Vinylben-zyl(trimethylammonium chloride) and vinyl benzoate were introduced as charged monomers labellingthe binding site and were allowed to self-organize around the protein. The subsequent polymerizationwas made by radical polymerization of vinylbenzene. Neutral PIM (N/PIM) prepared without orientedcharges and non imprinted materials (NIM) obtained without template were used as controls.These materials were used to develop simple and inexpensive potentiometric sensor for PSA. Theywere included as ionophores in plasticized PVC membranes, and tested over electrodes of solid or liq-uid conductive contacts, made of conductive carbon over a syringe or of inner reference solution overmicropipette tips. The electrodes with charged monomers showed a more stable and sensitive response,with an average slope of -44.2 mV/decade and a detection limit of 5.8 × 10−11mol/L (2 ng/mL). The cor-responding non-imprinted sensors showed lower sensitivity, with average slopes of -24.8 mV/decade.The best sensors were successfully applied to the analysis of serum, with recoveries ranging from 96.9to 106.1% and relative errors of 6.8%.

New and low cost plastic membrane electrode with low detection limits for sulfadimethoxine determination in aquaculture waters

Sulfadimethoxine (SDM) is one of the drugs, often used in the aquaculture sector to prevent the spread of disease in freshwater fish aquaculture. Its spread through the soil and surface water can contribute to an increase in bacterial resistance. It is therefore important to control this product in the environment. This work proposes a simple and low-cost potentiometric device to monitor the levels of SDM in aquaculture waters, thus avoiding its unnecessary release throughout the environment. The device combines a micropipette tip with a PVC membrane selective to SDM, prepared from an appropriate cocktail, and an inner reference solution. The membrane includes 1% of a porphyrin derivative acting as ionophore and a small amount of a lipophilic cationic additive (corresponding to 0.2% in molar ratio). The composition of the inner solution was optimized with regard to the kind and/or concentration of primary ion, chelating agent and/or a specific interfering charged species, in different concentration ranges. Electrodes constructed with inner reference solutions of 1 × 10−8 mol/L SDM and 1 × 10−4 mol/L chromate ion showed the best analytical features. Near-Nernstian response was obtained with slopes of −54.1 mV/decade, an extraordinary detection limit of 7.5 ng/mL (2.4 × 10−8 mol/L) when compared with other electrodes of the same type. The reproducibility, stability and response time are good and even better than those obtained by liquid contact ISEs. Recovery values of 98.9% were obtained from the analysis of aquaculture water samples.

A potentiometric magnetic immunoassay for rapid detection of Salmonella typhimurium

Potentiometric detection with homemade polymeric membrane microelectrodes was coupled to a magnetic sandwich immunoassay for Salmonella typhimurium determination. Cadmium and sodium ion selective electrodes were used respectively as indicator and pseudo-reference electrodes and were prepared in pipette tips to allow potentiometric measurements in microliter sample volumes. In the proposed method, the concentration of S. typhimurium was proportional to the amount of cadmium released upon dissolution of a CdS nanoparticle labeled to the secondary detection antibody. The limit of detection was 2 cells per 100 μL. The immunomagnetic assay with potentiometric detection is suitable for sensitive and rapid (average total time per assay of 75 minutes) detection of S. typhimurium in milk samples. The proposed method is easy to perform, safe, sensitive, and low cost and has potential for in situ analysis.

Crowdsourcing innovation: a strategy to leverage enterprise innovation

Innovation is recognized by academics and practitioners as an essential competitive enabler for any company to survive, to remain competitive and to grow. Investments in tasks of R&D have not always brought the expected results. But that doesn't mean that the outcomes would not be useful to other companies of the same business area or even from another area. Thus, there is much knowledge already available in the market that can be helpful to some and profitable to others. So, the ideas and expertise can be found outside a company's boundaries and also exported from within. Information, knowledge, experience, wisdom is already available in the millions of the human beings of this planet, the challenge is to use them through a network to produce new ideas and tips that can be useful to a company with less costs. This was the reason for the emergence of the area of crowdsourcing innovation. Crowdsourcing innovation is a way of using the Web 2.0 tools to generate new ideas through the heterogeneous knowledge available in the global network of individuals highly qualified and with easy access to information and technology. So, a crowdsourcing innovation broker is an organization that mediates the communication and relationship between the seekers - companies that aspire to solve some problem or to take advantage of any business opportunity - with a crowd that is prone to give ideas based on their knowledge, experience and wisdom. This paper makes a literature review on models of open innovation, crowdsourcing innovation, and technology and knowledge intermediaries, and discusses this new phenomenon as a way to leverage the innovation capacity of enterprises. Finally, the paper outlines a research design agendafor explaining crowdsourcing innovation brokering phenomenon, exploiting its players, main functions, value creation process, and knowledge creation in order to define a knowledge metamodel of such intermediaries.

Compact ion-source based on superionic rubidium silver iodide (RbAg4I5) solid electrolyte

Dissertação para obtenção do Grau de Mestre em Engenharia Física

Tratamento cirúrgico da hipertensão porta na esquistossomose mansoni

Define-se a hipertensão porta pela presença de um gradiente de pressão venosa hepática superior a 5mmHg. Ela é causada geralmente pelo aumento da resistência do leito vascular porta-hepático em decorrência de obstrução ao fluxo sanguíneo. Nas formas graves da esquistossomose há aumento progressivo da pressão porta e o desenvolvimento de varizes nos órgãos intra-abdominais, no retroperitônio e na parede do abdômen. A principal complicação desse processo é o sangramento digestivo, proveniente, na maioria dos casos, das varizes esofágicas e gástricas. Para o tratamento, diversos procedimentos clínicos (propranolol, somatostatina e octeotrida), endoscópicos (escleroterapia, clipes e ligaduras de varizes), vasculares (TIPS - shunt intra-hepático transjugular portasistêmico) e cirúrgicos (derivações portassistêmicas e desconexões portavarizes) têm sido propostos. Neste artigo, o autor apresenta revisão crítica sobre os vários tratamentos propostos, enfatizando os procedimentos cirúrgicos.

The occurrence and dissemination of methicillin and vancomycin-resistant Staphylococcus in samples from patients and health professionals of a university hospital in Recife, State of Pernambuco, Brazil

Introduction Methicillin-resistant Staphylococcus aureus (MRSA) strains have been responsible for many nosocomial outbreaks. Within hospitals, colonized employees often act as reservoirs for the spread of this organism. This study collected clinical samples of 91 patients admitted to the intensive care unit (ICU), hemodialysis/nephrology service and surgical clinic, and biological samples from the nasal cavities of 120 professionals working in those environments, of a University Hospital in Recife, in the State of Pernambuco, Brazil. The main objective of this study was to determine the occurrence and dissemination of methicillin- and vancomycin-resistant Staphylococcus spp. Methods The isolates obtained were tested for susceptibility to oxacillin and vancomycin and detection of the mecA gene. In addition, the isolates were evaluated for the presence of clones by ribotyping-polymerase chain reaction (PCR). Results MRSA occurrence, as detected by the presence of the mecA gene, was more prevalent among nursing technicians; 48.1% (13/27) and 40.7% (11/27) of the isolates were from health professionals of the surgical clinic. In patients, the most frequent occurrence of mecA-positive isolates was among the samples from catheter tips (33.3%; 3/9), obtained mostly from the hemodialysis/nephrology service. Eight vancomycin-resistant strains were found among the MRSA isolates through vancomycin screening. Based on the amplification patterns, 17 ribotypes were identified, with some distributed between patients and professionals. Conclusions Despite the great diversity of clones, which makes it difficult to trace the source of the infection, knowledge of the molecular and phenotypic profiles of Staphylococcus samples can contribute towards guiding therapeutic approaches in the treatment and control of nosocomial infections.

Contraexemplos e raciocínio dedutivo

Tese de Doutoramento apresentada ao ISPA - Instituto Universitário

Ion-beam sources based on superionic solid electrolytes

An ion emitter consisting of a sharp silver tip covered in RbAg4I5 solid electrolyte film has been developed and studied. An accelerating potential is applied and Ag+ ions are emitted from the tip’s apex by field evaporation. The emitted ions are collected by a Faraday cup, producing a current on the pico/nanoampere level which is read by an electrometer. The tips were produced mechanically by sandpaper polishing. The sharpest tip produced had a 2:4 m apex radius. Two deposition methods were studied: thermal vacuum and pulsed laser deposition. The best tip produced a peak current value of 96nA at 180oC, and a quasi-stable 4nA emission current at 160oC, both using an extraction potential of 10kV . The emission dependence on time, temperature and accelerating potential has been studied. Deposited films were characterized by X-ray diffraction (XRD), profilometry, optical and Scanning Electron Microscope (SEM) and Secondary Ion Mass Spectroscopy (SIMS) measurements. Several ion emitters were developed, the latter ones were all able to maintain stable high ion emissions for long periods of time. This investigation was a continuation of an ongoing project backed by the European Space Agency, with the objective of making a proof of concept of this kind of ion emitter with potential application on ion thrusters for orbiting satellites. Going forward, it would be interesting to make a finer analysis of the electrolyte’s conductivity at high temperatures, explore Wien Effect-based emission and to further develop a multi-tip ion emitter prototype.

Fatigue life assessment of endodontic instruments subjected to multi planar curvature

This present study aimed to investigate the fatigue life of unused (new) endodontic instruments made of NiTi with control memory by Coltene™ and subjected to the multi curvature of a mandibular first molar root canal. Additionally, the instrument‟s structural behaviour was analysed through non-linear finite element analysis (FEA). The fatigue life of twelve Hyflex™ CM files was assessed while were forced to adopt a stance with multiple radius of curvature, similar to the ones usually found in a mandibular first molar root canal; nine of them were subjected to Pecking motion, a relative movement of axial type. To achieve this, it was designed an experimental setup with the aim of timing the instruments until fracture while worked inside a stainless steel mandibular first molar model with relative axial motion to simulate the pecking motion. Additionally, the model‟s root canal multi-curvature was confirmed by radiography. The non-linear finite element analysis was conducted using the computer aided design software package SolidWorks™ Simulation, in order to define the imposed displacement required by the FEA, it was necessary to model an endodontic instrument with simplified geometry using SolidWorks™ and subsequently analyse the geometry of the root canal CAD model. The experimental results shown that the instruments subjected to pecking motion displayed higher fatigue life values and higher lengths of fractured tips than those with only rotational relative movement. The finite element non-linear analyses shown, for identical conditions, maximum values for the first principal stress lower than the yield strength of the material and those were located in similar positions to the instrument‟s fracture location determined by the experimental testing results.

Anphira branchialis GEN. ET SP. NOV. (CRUSTACEA, ISOPODA, CYMOTHOIDAE) A GILL CAVITY PARASITE OF PIRANHAS (Serrasalmus SPP.) IN THE BRAZILIAN AMAZON

Anphira branchialisgen. et sp. nov. (Crustacea, Isopoda, Cymothoidae) is described from the dorsal areas of the gill chambers of three species of piranhas (Serrasalmusspp.). The fishes were caught in rivers near Manaus, Amazonas State and on Maracá island, Federal Territory of Roraima, Brasil. The new genus and species is characterized by having large, flat coxal plates on ail 7 pereonites. These plates usually extend beyond the margins of the following segments and the 7th ones extend nearly to the pleotelson and cover the lateral margins of the pleonites. The mandible of this species is rounded, "foot shaped" and without incisor. The mandibular palp is short and stout. The maxillules have 3 terminal and 2 subterminal spines. The pleopods are simple lamellar structures with rounded tips. Evidence is presented that these parasites feed on gill filaments.