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OBJECTIVE: To update the recommendations to support decisions regarding the pharmacological treatment of patients hospitalized with COVID-19 in Brazil. METHODS: Experts, including representatives of the Ministry of Health and methodologists, created this guideline. The method used for the rapid development of guidelines was based on the adoption and/or adaptation of existing international guidelines (GRADE ADOLOPMENT) and supported by the e-COVID-19 RecMap platform. The quality of the evidence and the preparation of the recommendations followed the GRADE method. RESULTS: Twenty-one recommendations were generated, including strong recommendations for the use of corticosteroids in patients using supplemental oxygen and conditional recommendations for the use of tocilizumab and baricitinib for patients on supplemental oxygen or on noninvasive ventilation and anticoagulants to prevent thromboembolism. Due to suspension of use authorization, it was not possible to make recommendations regarding the use of casirivimab + imdevimab. Strong recommendations against the use of azithromycin in patients without suspected bacterial infection, hydroxychloroquine, convalescent plasma, colchicine, and lopinavir + ritonavir and conditional recommendations against the use of ivermectin and remdesivir were made. CONCLUSION: New recommendations for the treatment of hospitalized patients with COVID-19 were generated, such as those for tocilizumab and baricitinib. Corticosteroids and prophylaxis for thromboembolism are still recommended, the latter with conditional recommendation. Several drugs were considered ineffective and should not be used to provide the best treatment according to the principles of evidence-based medicine and to promote resource economy.

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ABSTRACT Objective: To update the recommendations to support decisions regarding the pharmacological treatment of patients hospitalized with COVID-19 in Brazil. Methods: Experts, including representatives of the Ministry of Health and methodologists, created this guideline. The method used for the rapid development of guidelines was based on the adoption and/or adaptation of existing international guidelines (GRADE ADOLOPMENT) and supported by the e-COVID-19 RecMap platform. The quality of the evidence and the preparation of the recommendations followed the GRADE method. Results: Twenty-one recommendations were generated, including strong recommendations for the use of corticosteroids in patients using supplemental oxygen and conditional recommendations for the use of tocilizumab and baricitinib for patients on supplemental oxygen or on noninvasive ventilation and anticoagulants to prevent thromboembolism. Due to suspension of use authorization, it was not possible to make recommendations regarding the use of casirivimab + imdevimab. Strong recommendations against the use of azithromycin in patients without suspected bacterial infection, hydroxychloroquine, convalescent plasma, colchicine, and lopinavir + ritonavir and conditional recommendations against the use of ivermectin and remdesivir were made. Conclusion: New recommendations for the treatment of hospitalized patients with COVID-19 were generated, such as those for tocilizumab and baricitinib. Corticosteroids and prophylaxis for thromboembolism are still recommended, the latter with conditional recommendation. Several drugs were considered ineffective and should not be used to provide the best treatment according to the principles of evidence-based medicine and to promote resource economy.

RESUMO Objetivo: Atualizar as recomendações para embasar as decisões para o tratamento farmacológico de pacientes hospitalizados com COVID-19 no Brasil. Métodos: A elaboração desta diretriz foi feita por especialistas, incluindo representantes do Ministério da Saúde e metodologistas. O método utilizado para o desenvolvimento rápido de diretrizes baseou-se na adoção e/ou adaptação de diretrizes internacionais existentes (GRADE ADOLOPMENT) e contou com o apoio da plataforma e-COVID-19 RecMap. A qualidade das evidências e a elaboração das recomendações seguiram o método GRADE. Resultados: Chegaram-se a 21 recomendações, incluindo recomendações fortes quanto ao uso de corticosteroides em pacientes em uso de oxigênio suplementar e recomendações condicionais para o uso de tocilizumabe e baricitinibe, em pacientes com oxigênio suplementar ou ventilação não invasiva, e de anticoagulantes, para prevenção de tromboembolismo. Devido à suspensão da autorização de uso, não foi possível fazer recomendações para o tratamento com casirivimabe + imdevimabe. Foram feitas recomendações fortes contra o uso de azitromicina em pacientes sem suspeita de infecção bacteriana, hidroxicloroquina, plasma convalescente, colchicina e lopinavir + ritonavir, além de recomendações condicionais contra o uso de ivermectina e rendesivir. Conclusão: Foram criadas novas recomendações para o tratamento de pacientes hospitalizados com COVID-19, como as recomendações de tocilizumabe e baricitinibe. Ainda são recomendados corticosteroides e profilaxia contra tromboembolismo, esta em caráter condicional. Vários medicamentos foram considerados ineficazes e não devem ser usados, no intuito de proporcionar o melhor tratamento segundo os princípios da medicina baseada em evidências e promover a economia de recursos.

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OBJECTIVE: Several therapies are being used or proposed for COVID-19, and many lack appropriate evaluations of their effectiveness and safety. The purpose of this document is to develop recommendations to support decisions regarding the pharmacological treatment of patients hospitalized with COVID-19 in Brazil. METHODS: A group of 27 experts, including representatives of the Ministry of Health and methodologists, created this guideline. The method used for the rapid development of guidelines was based on the adoption and/or adaptation of existing international guidelines (GRADE ADOLOPMENT) and supported by the e-COVID-19 RecMap platform. The quality of the evidence and the preparation of the recommendations followed the GRADE method. RESULTS: Sixteen recommendations were generated. They include strong recommendations for the use of corticosteroids in patients using supplemental oxygen, the use of anticoagulants at prophylactic doses to prevent thromboembolism and the nonuse of antibiotics in patients without suspected bacterial infection. It was not possible to make a recommendation regarding the use of tocilizumab in patients hospitalized with COVID-19 using oxygen due to uncertainties regarding the availability of and access to the drug. Strong recommendations against the use of hydroxychloroquine, convalescent plasma, colchicine, lopinavir + ritonavir and antibiotics in patients without suspected bacterial infection and also conditional recommendations against the use of casirivimab + imdevimab, ivermectin and rendesivir were made. CONCLUSION: To date, few therapies have proven effective in the treatment of hospitalized patients with COVID-19, and only corticosteroids and prophylaxis for thromboembolism are recommended. Several drugs were considered ineffective and should not be used to provide the best treatment according to the principles of evidence-based medicine and promote economical resource use.

OBJETIVOS: Há diversas terapias sendo utilizadas ou propostas para a COVID-19, muitas carecendo de apropriada avaliação de efetividade e segurança. O propósito deste documento é elaborar recomendações para subsidiar decisões sobre o tratamento farmacológico de pacientes hospitalizados com COVID-19 no Brasil. MÉTODOS: Um grupo de 27 membros, formado por especialistas, representantes do Ministério da Saúde e metodologistas, integra essa diretriz. Foi utilizado o método de elaboração de diretrizes rápidas, tomando por base a adoção e/ou a adaptação de recomendações a partir de diretrizes internacionais existentes (GRADE ADOLOPMENT), apoiadas pela plataforma e-COVID-19 RecMap. A qualidade das evidências e a elaboração das recomendações seguiram o método GRADE. RESULTADOS: Foram geradas 16 recomendações. Entre elas, estão recomendações fortes para o uso de corticosteroides em pacientes em uso de oxigênio suplementar, para o uso de anticoagulantes em doses de profilaxia para tromboembolismo e para não uso de antibacterianos nos pacientes sem suspeita de infecção bacteriana. Não foi possível fazer uma recomendação quanto à utilização do tocilizumabe em pacientes hospitalizados com COVID-19 em uso de oxigênio, pelas incertezas na disponibilidade e de acesso ao medicamento. Foi feita recomendação para não usar azitromicina, casirivimabe + imdevimabe, cloroquina, colchicina, hidroxicloroquina, ivermectina, lopinavir/ ritonavir, plasma convalescente e rendesivir. CONCLUSÃO: Até o momento, poucas terapias se provaram efetivas no tratamento do paciente hospitalizado com COVID-19, sendo recomendados apenas corticosteroides e profilaxia para tromboembolismo. Diversos medicamentos foram considerados ineficazes, devendo ser descartados, de forma a oferecer o melhor tratamento pelos princípios da medicina baseada em evidências e promover economia de recursos não eficazes.

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Há diversas terapias sendo utilizadas ou propostas para a COVID-19, muitas carecendo de apropriada avaliação de efetividade e segurança. O propósito deste documento é elaborar recomendações para subsidiar decisões sobre o tratamento farmacológico de pacientes hospitalizados com COVID-19 no Brasil. Métodos: Um grupo de 27 membros, formado por especialistas, representantes do Ministério da Saúde e metodologistas, integra essa diretriz. Foi utilizado o método de elaboração de diretrizes rápidas, tomando por base a adoção e/ou a adaptação de recomendações a partir de diretrizes internacionais existentes (GRADE ADOLOPMENT), apoiadas pela plataforma e-COVID-19 RecMap. A qualidade das evidências e a elaboração das recomendações seguiram o método GRADE. Resultados: Foram geradas 16 recomendações. Entre elas, estão recomendações fortes para o uso de corticosteroides em pacientes em uso de oxigênio suplementar, para o uso de anticoagulantes em doses de profilaxia para tromboembolismo e para não uso de antibacterianos nos pacientes sem suspeita de infecção bacteriana. Não foi possível fazer uma recomendação quanto à utilização do tocilizumabe em pacientes hospitalizados com COVID-19 em uso de oxigênio, pelas incertezas na disponibilidade e de acesso ao medicamento. Foi feita recomendação para não usar azitromicina, casirivimabe + imdevimabe, cloroquina, colchicina, hidroxicloroquina, ivermectina, lopinavir/ ritonavir, plasma convalescente e rendesivir. Conclusão: Até o momento, poucas terapias se provaram efetivas no tratamento do paciente hospitalizado com COVID-19, sendo recomendados apenas corticosteroides e profilaxia para tromboembolismo. Diversos medicamentos foram considerados ineficazes, devendo ser descartados, de forma a oferecer o melhor tratamento pelos princípios da medicina baseada em evidências e promover economia de recursos não eficazes.

Several therapies are being used or proposed for COVID-19, and many lack appropriate evaluations of their effectiveness and safety. The purpose of this document is to develop recommendations to support decisions regarding the pharmacological treatment of patients hospitalized with COVID-19 in Brazil. Methods: A group of 27 experts, including representatives of the Ministry of Health and methodologists, created this guideline. The method used for the rapid development of guidelines was based on the adoption and/or adaptation of existing international guidelines (GRADE ADOLOPMENT) and supported by the e-COVID-19 RecMap platform. The quality of the evidence and the preparation of the recommendations followed the GRADE method. Results: Sixteen recommendations were generated. They include strong recommendations for the use of corticosteroids in patients using supplemental oxygen, the use of anticoagulants at prophylactic doses to prevent thromboembolism and the nonuse of antibiotics in patients without suspected bacterial infection. It was not possible to make a recommendation regarding the use of tocilizumab in patients hospitalized with COVID-19 using oxygen due to uncertainties regarding the availability of and access to the drug. Strong recommendations against the use of hydroxychloroquine, convalescent plasma, colchicine, lopinavir + ritonavir and antibiotics in patients without suspected bacterial infection and also conditional recommendations against the use of casirivimab + imdevimab, ivermectin and rendesivir were made. Conclusion: To date, few therapies have proven effective in the treatment of hospitalized patients with COVID-19, and only corticosteroids and prophylaxis for thromboembolism are recommended. Several drugs were considered ineffective and should not be used to provide the best treatment according to the principles of evidence-based medicine and promote economical resource use.

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Several countries maintain universal health coverage, which implies responsibility to organize delivery formats of healthcare services and products for citizens. In Brazil, the health system has a principle of universal access for more than 30 years, but many deficiencies remain and the country observes a day practice for those seeking judicial decisions to determine provision of healthcare.

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BACKGROUND AND OBJECTIVE: Managed entry agreements (MEAs) consist of a set of instruments to reduce the uncertainty and the budget impact of new high-priced medicines; however, there are concerns. There is a need to critically appraise MEAs with their planned introduction in Brazil. Accordingly, the objective of this article is to identify and appraise key attributes and concerns with MEAs among payers and their advisers, with the findings providing critical considerations for Brazil and other high- and middle-income countries. METHODS: An integrative review approach was adopted. This involved a review of MEAs across countries. The review question was 'What are the health technology MEAs that have been applied around the world?' This review was supplemented with studies not retrieved in the search known to the senior-level co-authors including key South American markets. It also involved senior-level decision makers and advisers providing guidance on the potential advantages and disadvantages of MEAs and ways forward. RESULTS: Twenty-five studies were included in the review. Most MEAs included medicines (96.8%), focused on financial arrangements (43%) and included mostly antineoplastic medicines. Most countries kept key information confidential including discounts or had not published such data. Few details were found in the literature regarding South America. Our findings and inputs resulted in both advantages including reimbursement and disadvantages including concerns with data collection for outcome-based schemes. CONCLUSIONS: We are likely to see a growth in MEAs with the continual launch of new high-priced and often complex treatments, coupled with increasing demands on resources. Whilst outcome-based MEAs could be an important tool to improve access to new innovative medicines, there are critical issues to address. Comparing knowledge, experiences, and practices across countries is crucial to guide high- and middle-income countries when designing their future MEAs.

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Aedes aegypti is one of the most important disease vectors in the world. Because their gut is the first site of interaction with pathogens, it is important to understand A. aegypti gut physiology. In this study, we investigated the mechanisms of pH control in the midgut of A. aegypti females under different nutritional conditions. We found that unfed females have an acidic midgut (pH âˆ¼6). The midgut of unfed insects is actively maintained at pH 6 regardless of the ingestion of either alkaline or acidic buffered solutions. V-ATPases are responsible for acidification after ingestion of alkaline solutions. In blood-fed females, the abdominal midgut becomes alkaline (pH 7.54), and the luminal pH decreases slightly throughout blood digestion. Only ingested proteins were able to trigger this abrupt increase in abdominal pH. The ingestion of amino acids, even at high concentrations, did not induce alkalinisation. During blood digestion, the thoracic midgut remains acidic, becoming a suitable compartment for carbohydrate digestion, which is in accordance with the higher alpha-glucolytic activity detected in this compartment. Ingestion of blood releases alkalising hormones in the haemolymph, which induce alkalinisation in ex vivo preparations. This study shows that adult A. aegypti females have a very similar gut physiology to that previously described for Lutzomyia longipalpis It is likely that all haematophagous Nematocera exhibit the same type of physiological behaviour.

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OBJECTIVES: Health technology financing is often based on randomized controlled trials (RCTs), which are often the same ones used for licensing. Because they are designed to show the best possible results, typically Phase III studies are conducted under ideal and highly controlled conditions. Consequently, it is not surprising that technologies do not always perform in real life in the same way as controlled conditions. Because financing (and price paid) decisions can be made with overestimated results, health authorities need to ask whether health systems achieve the results they expect when they choose to pay for a technology. The optimal way to answer this question is to assess the performance of financed technologies in real-world settings. Health technology performance assessment (HTpA) refers to the systematic evaluation of the properties, effects, and/or impact of a health intervention or health technology in the real world to provide information for investment/disinvestment decisions and clinical guideline updates. The objective is to describe the development and principal aspects of the Guideline for HTpA commissioned by the Brazilian Ministry of Health. METHODS: Our methods used include extensive literature review, refinement with experts across countries, and public consultation. RESULTS: A comprehensive guideline was developed, which has been adopted by the Brazilian government. CONCLUSION: We believe the guideline, with its particular focus on disinvestment, along with the creation of a specific program for HTpA, will allow the institutionalization and continuous improvement of the scientific methods to use real-world evidence to optimize available resources not only in Brazil but across countries.

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Objetivos: Resumir os principais pontos da Diretriz de Avaliação Econômica em Saúde (AES) do Ministério da Saúde. Métodos: As diretrizes para AES no Brasil foram desenvolvidas por intermédio de múltiplas rodadas de trabalho iterativas por grupo multidisciplinar de especialistas em economia da saúde e foram submetidas à consulta pública. Resultados: O problema deve ser definido por meio de uma questão de pesquisa estruturada. O estudo pode ser baseado em dados primários ou em modelagem, em que o primeiro aumenta a validade interna dos resultados e o segundo, a capacidade de generalização do estudo. Quando o trabalho for baseado em modelagem e focado em doença crônica, o modelo de Markov pode ser usualmente empregado, quando não houver necessidades que apontem para simulação de eventos discretos (como competição dos indivíduos por recursos escassos) ou modelos de transmissão dinâmica (em vacinação e/ou doenças infecciosas com alta transmissão entre indivíduos). O horizonte temporal preferencial é o de tempo de vida, e a taxa de desconto padrão é de 5% para custo e efetividade. Os custos devem representar a perspectiva do Sistema Único de Saúde (SUS), podendo ser estimados por macrocusteio ou microcusteio. Sempre que possível, os resultados devem ser apresentados no formato de custo por ano de vida salvo ajustado para qualidade, para facilitar comparações com outros estudos. Análises de sensibilidade devem ser extensamente empregadas, de forma a avaliar o impacto da incerteza nos resultados produzidos. Conclusões: Espera-se que, com a padronização da metodologia proposta na Diretriz, a produção de AES no país tenha incremento na sua qualidade e reprodutibilidade.

Objectives: To summarize the main points from the Brazilian's Ministry of Health Economic Evaluations (HEE) guideline. Methods: The guideline was developed through multiple rounds of iterative work, conducted by a multidisciplinary team of specialists in health economics, and where submitted to public consultation. Results: The decision problem should be defined through a structured research question. The study can be either primary data or model-based; in the first case, there is greater internal validity, while the second generates a superior generalizability. When the study is model-based and focused on a chronic disease, a Markov model can be usually employed, except for situations that points towards the need of a discrete event simulation (such as competition of individuals for scarce resources) or a dynamic transition model (for example, vaccination models and infectious diseases with high transmission rates between individuals). The preferred time horizon is the lifetime one, and the default discount rate is 5% for both costs and effectiveness. Costs should represent the Unified Health System (SUS) perspective and can be estimated through either gross-costing or micro-costing. Results should be presented as costs per quality adjusted life years (QALYs) whenever possible, to facilitate comparison with other studies. Sensitivity analyses should be widely employed, in order to evaluate the impact of uncertainty in the results produced by the model. Conclusions: It is expected that, with the standardization proposed in this guideline, the HEE production in Brazil has gains in quality and reproducibility.

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Some reports have described the interference of Leishmania on sand flies physiology, and such behavior most likely evolved to favor the development and transmission of the parasite. Most of these studies showed that Leishmania could modulate the level of proteases in the midgut after an infective blood meal, and decreased proteolytic activity is indeed beneficial for the development of promastigotes in the gut of sand flies. In the present study, we performed a detailed investigation of the intestinal pH in Lutzomyia longipalpis females naturally infected with Leishmania infantum and investigated the production of trypsin by these insects using different approaches. Our results allowed us to propose a mechanism by which these parasites interfere with the physiology of L. longipalpis to decrease the production of proteolytic enzymes. According to our hypothesis L. infantum promastigotes indirectly interfere with the production of trypsin by modulating the mechanism that controls the intestinal pH via the action of a yet non-identified substance released by promastigote forms inside the midgut. This substance is not an acid, whose action would be restrict on to release H+ to the medium, but is a substance that is able to interfere with midgut physiology through a mechanism involving pH control. According to our hypothesis, as the pH decreases, the proteolytic enzymes efficiency is also reduced, leading to a decline in the supply of amino acids to the enterocytes: this decline reduces the stimulus for protease production because it is regulated by the supply of amino acids, thus leading to a delay in digestion.

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Budget impact analysis (BIA) provides operational financial forecasts to implement new technologies in healthcare systems. There were no previous specific recommendations to conduct such analyses in Brazil. This paper reviews BIA methods for health technologies and proposes BIA guidelines for the public and private Brazilian healthcare system. The following recommendations were made: adopt the budget administrator's perspective; use a timeframe of 1 to 5 years; compare reference and alternative scenarios; consider the technology's rate of incorporation; estimate the target population by either an epidemiological approach or measured demand; consider restrictions on technologies' indication or factors that increase the demand for them; consider direct and averted costs; do not adjust for inflation or discounts; preferably, integrate information on a spreadsheet; calculate the incremental budget impact between scenarios; and summarize information in a budget impact report.

Análises de impacto orçamentário (AIO) fornecem previsões financeiras operacionais para a implementação de uma nova tecnologia em um sistema de saúde. Até o momento, não havia recomendações específicas para o desenvolvimento de AIO no Brasil. O presente trabalho apresenta uma revisão dos métodos usados nas AIO de tecnologias da saúde e propõe recomendações para seu uso nos âmbitos do SUS e do sistema de saúde suplementar. As recomendações principais são: analisar pela perspectiva do gestor; empregar horizonte temporal de um a cinco anos; comparar cenários de referência e alternativos; considerar taxa de incorporação da tecnologia; delimitar a população de interesse pela abordagem epidemiológica ou por demanda aferida; considerar restrições para acesso ou fatores indutores de demanda; considerar custos diretos incorridos e evitados; não ajustar para inflação ou descontos; integrar as informações em planilha eletrônica; calcular o impacto orçamentário diferencial entre cenários; sintetizar as informações em um relatório de impacto orçamentário.

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Budget impact analysis (BIA) provides operational financial forecasts to implement new technologies in healthcare systems. There were no previous specific recommendations to conduct such analyses in Brazil. This paper reviews BIA methods for health technologies and proposes BIA guidelines for the public and private Brazilian healthcare system. The following recommendations were made: adopt the budget administrator's perspective; use a timeframe of 1 to 5 years; compare reference and alternative scenarios; consider the technology's rate of incorporation; estimate the target population by either an epidemiological approach or measured demand; consider restrictions on technologies' indication or factors that increase the demand for them; consider direct and averted costs; do not adjust for inflation or discounts; preferably, integrate information on a spreadsheet; calculate the incremental budget impact between scenarios; and summarize information in a budget impact report.

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OBJECTIVES: This study reports on the Brazilian experience of developing a specialized bulletin, the Brazilian Health Technology Assessment Bulletin (BRATS), on health technology assessments (HTA). METHODS: The editorial process, format, and dissemination strategy of the publication are presented. A critical appraisal of the available issues was made using the checklist for HTA reports of the International Network of Agencies for Health Technology Assessment. The initial impact was estimated based on a retrospective observational measurement of the types of publications that cite the bulletin as a source of information. The publications citing BRATS were identified using Google Scholar. RESULTS: Since June 2008, fourteen issues of the bulletin have been produced. BRATS has not presented any significant limitation that would compromise generalizations of its results within the Brazilian context. The initial impact of the bulletin, however, has been small, which may be due to its exclusively electronic dissemination format and technical language. We found nine publications citing BRATS in Google Scholar. CONCLUSIONS: It is hoped that the bulletin will promote the continuity of HTA actions among health-sector managers and professionals in Brazil.

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O avanço tecnológico das últimas décadas proporcionou melhorias na qualidade da saúde da população e redução nas taxas de mortalidade de um número considerável de doenças. Entretanto, grande oferta destas novas tecnologias torna necessário que, além dos benefícios, seus riscos e custos sejam avaliados no processo de tomada de decisão para disponibilizá-las ao sistema de saúde, promovendo o uso racional de tecnologias. Com a necessidade de institucionalizar um modelo de processo de incorporação de tecnologias em saúde que fosse amparado legalmente, foi publicada a Lei 12.401/2011 que cria a Comissão Nacional de Incorporação de Tecnologias no SUS ­ CONITEC, com o papel de assessorar o Ministério da Saúde quanto à incorporação, exclusão ou alteração de novas tecnologias no SUS. A nova legislação fixa um prazo para a tomada de decisão, bem como inclui a análise baseada em evidências, levando em consideração aspectos como eficácia, acurácia, efetividade e a segurança da tecnologia, além da avaliação econômica comparativa dos benefícios e dos custos em relação às tecnologias já existentes. Espera-se, com isso, que o processo de incorporação de tecnologias no SUS seja mais ágil, transparente e eficiente, garantindo à população brasileira o seu direito constitucional de acesso universal e integral à saúde.

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Nas últimas décadas, os gastos crescentes no setor saúde vêm preocupando diversos países, em especial aqueles cuja atenção à saúde é garantida pelo setor público. A grande pressão pela incorporação de tecnologias cada vez mais caras, além deimpactar no orçamento dos países, produz restrição ao acesso dos serviços de saúde, visto que não é possível garantir todas as intervenções a todos. Diante desta situação, técnicas para a racionalização dos gastos, tais como as análises econômicas em saúde, são utilizadas na tentativa de maximizar a saúde, mas resguardando a viabilidadefinanceira dos sistemas públicos de saúde. Países desenvolvidos com forte financiamento público, assim como Austrália, Canadá e Reino Unido têm empregado cada vez mais estas ferramentas para a tomada de decisão acerca da incorporação de novas tecnologias. O Brasil, na última década,também tem empreendido esforços para a adoção de critérios de custo-efetividade, tanto na entrada de medicamentos no mercado privado, com a alteração da lei de registro ecom a criação da Câmara de Regulação do Mercado de Medicamentos (CMED), quanto com o estabelecimento de uma Comissão de Incorporação de Tecnologias do Ministério da Saúde (CITEC). As decisões da CITEC são subsidiadas por estudos desenvolvidospela área de Avaliação de Tecnologias em Saúde (ATS) do Departamento de Ciência e Tecnologia (DECIT) do Ministério da Saúde. Neste aspecto, as Agências Nacionais de Vigilância Sanitária e de Saúde Suplementar também instituíram áreas de ATS pararesponder as suas demandas. E, apesar do avanço na institucionalização de áreas que utilizam análiseseconômicas na incorporação de tecnologias, ainda há uma fragilidade institucional nas etapas seguintes do ciclo de vida destas. O País também carece de profissionais capacitados e padece de uma desorganização neste campo causada principalmente pelasobreposição de atividades e atribuições das áreas que realizam a ATS no governofederal...

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Saliva of haematophagous arthropods contain biomolecules involved directly or indirectly with the haematophagy process, and among them are encountered some complement system inhibitors. The most obvious function for these inhibitors would be the protection of the midgut against injury by the complement. To investigate this hypothesis, Triatoma brasiliensis nymphs were forced to ingest human serum in conditions in which the protection of midgut by the inhibitors is bypassed. In these conditions, the anterior midgut epithelium was injured by the complement, causing cell death. Once some insects such as Aedes aegypti have no salivary inhibitors, we hypothesized the existence of intestinal inhibitors. The inhibitory activity was investigated in the intestine of A. aegypti as well as in the saliva and intestine of other three triatomine species (T. brasiliensis, T. infestans and Rhodnius prolixus) using an immunological method able to determine the level of deposition of some complement factors (C1q, C3b, or C4b) on the surface of complement activator molecules linked to microplates. This methodology permitted to identify which points along the activation phase of the complement cascade were inhibited. As expected, soluble contents of A. aegypti's intestine was capable to inhibit C3b deposition by the classical and alternative pathways. Saliva or soluble intestinal contents, obtained from triatomines were unable to inhibit C1q deposition by the classical pathway. C4b deposition by the classical pathway was inhibited by the intestinal contents from the three triatomines. On the other hand, only T. brasiliensis saliva inhibited C4b deposition. Both, saliva and intestinal contents from all triatomines were able to inhibit C3b deposition in the classical and alternative pathways. None of the material extracted from the intestinal cell membranes from the triatomines inhibited C3b deposition in the classical pathway. The existence of complement inhibitors may have important biological consequences which are discussed in detail.

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The objective of this work was to study the pattern of salivation of triatomines during feeding in mouse skin. Rhodnius prolixus was fed with a solution of the dye acridine orange or fluorescein. The saliva was efficiently labelled with acridine orange, probably due to the difference in pH between the salivary gland (6.0) and the hemolymph (6.5-7.0). This procedure was not effective at labelling the saliva of Triatoma infestans, however, fluorescent labelling of R. prolixus saliva allowed us to demonstrate that salivation occurs during entire feeding process. The saliva is released soon after the bite. In the probing phase, saliva is pumped continuously in the host skin, including around the blood vessels. During the engorgement phase, saliva is observed in a bolus within the blood vessel and some of it is sucked up by the insect, together with blood. The frequency of saliva emission inside the vessels was low (0.51+/-0.18 Hz). The saliva deposition in the microcirculation is continuous and modulated by the frequency of the cibarial pump because, when functioning at high frequency, cibarial pump sucks almost all saliva to the insect gut. This mechanism would determine the quantity of saliva deposited in the microcirculation as necessary, and consequently minimizing the host's immune response to salivary antigens.

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