Immunocytochemical identification of leishmania and Trypanosoma cruzi amastigotes in situ with homologous and heterologous polyclonal antibodies

The unlabelled antibody peroxidase-antiperoxidase method was used to study the immunocytochemical properties of Leishmania and Trypanosoma cruzi amastigotes in situ after tissues had been submitted to different fixation procedures. Antisera were obtained from rabbits chronically infected with different strains of T. cruzi or immunized with L. mexicana amazonensis and L. braziliensis guyanensis, and were applied on 5 µm thick sections. T. cruzi antigens were well stained by the three anti-T. cruzi sera and the two anti-heis.hmama.sera at optimum dilution between 1:1,000 and 1:2,000, regardless the parasite strain. Differently, the leishmanial antigens were revealed by Leishmania sera only at low dilutions (between 1:60 -1:160), whereas the anti-T. cruzi sera, at these low dilutions, gave rather weak stainings. Although there is no clear explanation for this immunocytochemical "reverse-monodirectional" cross-reactivity between Leishmania and T. cruzi, the present results show that polyclonal antibodies agains Leishmania species, when used for immunocytochemical detection of these parasites in situ, react more strongly with T. cruzi amastigotes than with the homologous amastigotes.

Controlo de qualidade interno: elaboração de um programa de Controlo de Qualidade Interno segundo as boas práticas da Qualidade

RESUMO: Esta dissertação pretende apresentar uma proposta para um programa de Controlo de Qualidade interno das hormonas tiroideias, segundo as boas práticas da qualidade. Para que se comprove o rigor e fiabilidade dos seus resultados analíticos, condição indispensável para que estes possam servir de base às mais diversas tomadas de decisão, toda a filosofia que envolve a qualidade assume um papel preponderante. Neste contexto a elaboração de um programa de controlo de qualidade adequado é muito importante e imprescindível. A realização do controlo de qualidade permite monitorizar o desempenho de todos os materiais, equipamentos, instrumentos e métodos analíticos bem como criar sinais de alerta para prevenir a emissão de resultados não-conformes e indicar a necessidade de ações corretivas. Permite também indicar a necessidade de melhorias em processos e em atividades ligadas aos operadores e consciencializar o pessoal de que o controlo da qualidade é um dever para com o cliente e tem a função de gerar confiança nos resultados obtidos. O controlo de qualidade interno abrange todos os procedimentos assumidos por um laboratório para avaliação contínua do seu trabalho. A sua finalidade é assegurar a consistência dos resultados diários e a sua conformidade com critérios definidos, avaliando a precisão dos ensaios e dando indicação do momento para se promoverem ações corretivas quando surge uma não conformidade. Segundo as melhores práticas da qualidade, serão calculados os valores do controlo de qualidade interno para as hormonas tiroideias, os seus limites e critérios (regras) de aceitabilidade, com base na relação entre o desempenho analítico e o Erro Máximo Admissível. Pretende-se assim, otimizar o desempenho do Controlo de Qualidade Interno, aperfeiçoando a capacidade de identificação do erro.-------- ABSTRACT: This paper intends to submit a proposal for a thyroid hormones internal quality Control program, according to the best quality practices. The whole philosophy involving quality plays a central role in order to prove the accuracy and reliability of the analytical results, a basic prerequisite for decision making. In this context the elaboration of an appropriate quality control program is essential and very important. Quality control allows the motorization of the performance of all materials, equipment, instruments and analytical methods, as well as the creation of warning signals indicating the need for corrective actions, to prevent the release of non-compliant results. It also indicates the need for improvements in the processes and operating activities as well as making the staff aware that quality control is a duty to the client and promotes confidence in the results. The internal quality control covers all procedures undertaken by a laboratory for a continuous evaluation of its performance. Its purpose is to ensure the consistency of the daily results and compliance with defined criteria, assessing the accuracy of the tests and indicating the moment to promote corrective actions when nonconformity appears. According to the best quality practices, the values of the internal quality control for the thyroid hormones, their limits and criteria (rules) of acceptability will be calculated, based on the relationship between analytical performance and the maximum allowable error. Thus, the aim is to optimize the performance of the Internal Quality Control, improving the ability for error detection and identification.

Regulation of the rice gene OsRMC under salt stress: identification and functional characterization of novel transcription factors

Dissertation presented to obtain the Ph.D degree in Biology

Recursive neuro fuzzy techniques for online identification and control

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores

Osmo- and thermo-adaptation in hyperthermophilic Archaea: identification of compatible solutes accumulation profiles, and biosynthetic routes in Archaeoglobus spp.

Dissertation presented to obtain the Ph.D degree in Biochemistry

Influence of canine brain decomposition on laboratory diagnosis of rabies

Canine brains infected with rabies virus were submitted to decomposition by being left at room temperature of 25 to 29oC for up to 168h. At 24h intervals, brain fragments were analyzed by immunofluorescence (IF) and by the mouse intracerebral inoculation (MI) test to confirm the diagnosis of rabies and to measure the putrefaction effect on the accuracy of the diagnosis. Forty eight h after the beginning of the experiment, the MI test showed signs of impairment with four negative results, while after 72h, 100% of the results were negative to the MI test and only one result was negative to the IF test, indicating that the threshold period for accurate diagnosis is 24 to 48h before putrefaction. The authors recommend the shipment of suspected cases of rabies to the laboratory for confirmation, but the use of putrid materials for diagnosis is meaningless because of false-negative results.

Identification of atmospheric pollutants control mechanisms during co-combustion of coal and non-toxic wastes

Doctoral dissertation for Ph.D. degree in Sustainable Chemistry

O erro na fase pré-analítica : amostras não conformes versus procedimentos

RESUMO: As Análises Clínicas são um precioso elemento entre os meios complementares de diagnóstico e terapêutica permitindo uma enorme panóplia de informações sobre o estado de saúde de determinado utente. O objetivo do laboratório é fornecer informação analítica sobre as amostras biológicas, sendo esta caracterizada pela sua fiabilidade, relevância e facultada em tempo útil. Assim, tratando-se de saúde, e mediante o propósito do laboratório, é notória a sua importância, bem como, a dos fatores associados para o cumprimento do mesmo. O bom desenrolar do ciclo laboratorial, compreendido pelas fases pré-analítica, analítica e pós-analítica é crucial para que o objetivo do laboratório seja cumprido com rigor e rapidez. O presente trabalho “O Erro na Fase Pré-Analítica: Amostras Não Conformes versus Procedimentos”, enquadrado no mestrado de Qualidade e Organização no Laboratório de Análises Clínicas, pretendeu enfatizar a importância da fase pré- analítica, sendo ela apontada como a primordial em erros que acabam por atrasar a saída de resultados ou por permitir que os mesmos não sejam fidedignos como se deseja, podendo acarretar falsos diagnósticos e decisões clínicas erradas. Esta fase, iniciada no pedido médico e finalizada com a chegada das amostras biológicas ao laboratório está entregue a uma diversidade de procedimentos que acarretam, por si só, uma grande diversidade de intervenientes, para além de uma variabilidade de factores que influenciam a amostra e seus resultados. Estes fatores, que podem alterar de algum modo a “veracidade” dos resultados analíticos, devem ser identificados e tidos em consideração para que estejamos convitos que os resultados auxiliam diagnósticos precisos e uma avaliação correta do estado do utente. As colheitas que por quaisquer divergências não originam amostras que cumpram o objectivo da sua recolha, não estando por isso em conformidade com o pretendido, constituem uma importante fonte de erro para esta fase pré-analítica. Neste estudo foram consultados os dados relativos a amostras de sangue e urina não conformes detetadas no laboratório, em estudo, durante o 1º trimestre de 2012, para permitir conhecer o tipo de falhas que acontecem e a sua frequência. Aos Técnicos de Análises Clínicas, colaboradores do laboratório, foi-lhes pedido que respondessem a um questionário sobre os seus procedimentos quotidianos e constituíssem, assim, a população desta 2ª parte do projeto. Preenchido e devolvido de forma anónima, este questionário pretendeu conhecer os procedimentos na tarefa de executar colheitas e, hipoteticamente, confrontá-los com as amostras não conformes verificadas. No 1ºsemestre de 2012 e num total de 25319 utentes registaram-se 146 colheitas que necessitaram de repetição por se verificarem não conformes. A “amostra não colhida” foi a não conformidade mais frequente (50%) versus a “má identificação” que registou somente 1 acontecimento. Houve ainda não conformidades que não se registaram como “preparação inadequada” e “amostra mal acondicionada”. Os técnicos revelaram-se profissionais competentes, conhecedores das tarefas a desempenhar e preocupados em executá-las com qualidade. Eliminar o erro não estará, seguramente, ao nosso alcance porém admitir a sua presença, detetá-lo e avaliar a sua frequência fará com que possamos diminuir a sua existência e melhorar a qualidade na fase pré-analítica, atribuindo-lhe a relevância que desempenha no processo laboratorial.-----------ABSTRACT:Clinical analyses are a precious element among diagnostic and therapeutic tests as they allow an enormous variety of information on the state of health of a user. The aim of the laboratory is to supply reliable, relevant and timely analytical information on biological samples. In health-related matters, in accordance with the objective of the laboratory, their importance is vital, as is the assurance that all the tools are in place for the fulfillment of its purpose. A good laboratory cycle, which includes the pre-analytical, analytical and post-analytical phases, is crucial in fulfilling the laboratory’s mission rapidly and efficiently. The present work - "Error in the pre-analytical phase: non-compliant samples versus procedures”, as part of the Master’s in Quality and Organization in the Clinical Analyses Laboratory, wishes to emphasize the importance of the pre-analytical phase, as the phase containing most errors which eventually lead to delays in the issue of results, or the one which enables those results not to be as reliable as desired, which can lead to false diagnosis and wrong clinical decisions. This phase, which starts with the medical request and ends with the arrival of the biological samples to the laboratory, entails a variety of procedures, which require the intervention of different players, not to mention a great number of factors, which influence the sample and the results. These factors, capable of somehow altering the “truth” of the analytical results, must be identified and taken into consideration so that we may ensure that the results help to make precise diagnoses and a correct evaluation of the user’s condition. Those collections which, due to any type of differences, do not originate samples capable of fulfilling their purpose, and are therefore not compliant with the objective, constitute an important source of error in this pre-analytical phase. In the present study, we consulted data from non-compliant blood and urine samples, detected at the laboratory during the 1st quarter of 2012, to find out the type of faults that happen and their frequency. The clinical analysis technicians working at the laboratory were asked to fill out a questionnaire regarding their daily procedures, forming in this way the population for this second part of the project. Completed and returned anonymously, this questionnaire intended to investigate the procedures for collections and, hypothetically, confront them with the verified non-compliant samples. In the first semester of 2012, and out of a total of 25319 users, 146 collections had to be repeated due to non-compliance. The “uncollected sample” was the most frequent non-compliance (>50%) versus “incorrect identification” which had only one occurrence. There were also unregistered non-compliance issues such as “inadequate preparation” and “inappropriately packaged sample”. The technicians proved to be competent professionals, with knowledge of the tasks they have to perform and eager to carry them out efficiently. We will certainly not be able to eliminate error, but recognizing its presence, detecting it and evaluating its frequency will help to decrease its occurrence and improve quality in the pre-analytical phase, giving it the relevance it has within the laboratory process.

Excito-repellency effect of deltamethrin on triatomines under laboratory conditions

This work demonstrates that deltamethrin in low doses produces an excito-repellency effect on triatomines, as already observed for mosquitoes. A wooden box covered with a cloth impregnated with deltamethrin at doses of 2.5 and 5mg ai/m² was utilized for the experiment. The triatomine species studied were Triatoma infestans, Panstrongylus megistus, Rhodnius neglectus and Triatoma sordida. Adults were released in one of the sides of the box and their position was noted in subsequent periods. The observations were realized on the day the cloth was impregnated and subsequently repeated at 30 and 60 days for T. sordida; on day 120, the remaining species were included. Insect mortality and attempts at flight from the box were also observed. Excito-repellency was evident for all species and doses up to day 120. The only species that attempted to fly was P. megistus. The excito-repellency effect may be considered as an additional advantage to the insecticide power, as it should be able to prevent the installation of new colonies by females that fly into the homes, and at the moment of the spraying, it should promote the flushing out of triatomines from the wall crevices and from other shelters.

Credit cycle identification: A Markov-switching application

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics