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    Desenvolvimento e validação de técnica imuno-histoquímica utilizando anticorpo monoclonal para o diagnóstico da leishmaniose cutânea

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    A leishmaniose tegumentar (LT) continua sendo problema global de saúde pública, que se manifesta principalmente através de lesões cutâneas (leishmaniose cutânea - LC). Na América Latina, o Brasil é o país com maior registro de casos, com várias espécies de Leishmania associadas aos casos humanos. O diagnóstico laboratorial é essencial e um dos grandes desafios para o controle da doença. Desta forma, desenvolvemos e validamos uma técnica de imuno-histoquímica (IHQ) utilizando anticorpo monoclonal (AcMo), para o diagnóstico da LC. Inicialmente, foi realizada uma revisão sistemática a fim de identificar potenciais alvos avaliados para o diagnóstico imunológico da LT. Antígenos com características distintas foram selecionados e considerados promissores para produção do AcMo e aplicação na técnica de IHQ. Os seis antígenos selecionados foram: triparedoxina mitocondrial peroxidase (mTXNPx); homológo do receptor para proteína quinase C ativada (LACK); fosfatase ácida secretada (sAcP); proteína de membrana dos kinetoplastídeos-11 (KMP-11); proteína hipotética (LbPH) e proteína quinase ativada por mitógeno 4 (MAPK4). As sequências de nucleotídeos dos antígenos selecionados foram sintetizadas e inseridas no plasmídeo pET28a. Vetores de clonagem e de expressão foram transformados com os plasmídeos, para produção dos antígenos recombinantes. Os antígenos produzidos foram utilizados como imunógenos em camundongos BALB/c, para produção dos AcMos por meio da técnica de hibridização somática. A imunorreatividade dos AcMos foi avaliada através da técnica de Western blotting, utilizando os respectivos antígenos recombinantes e antígenos solúveis de L. amazonensis, L. braziliensis e L. guyanensis. Em seguida, a técnica de IHQ foi realizada em biópsias de pele de hamsters experimentalmente infectados com estas espécies de Leishmania. A padronização da técnica de IHQ foi realizada utilizando o AcMo anti-mTXNPx e dois sistemas de detecção constituídos por polímero conjugados com as enzimas peroxidase (IHQ-POD) e fosfatase alcalina (IHQ-FA). A validação destes protocolos de IHQ foi relizada em biópsias de pele de 49 pacientes com LC diagnosticados por meio da reação em cadeia da polimerase quantitativa em tempo real (qPCR), que apresentavam resultados de exame direto e cultura, realizados como diagnóstico de rotina. Foram também incluídos 37 pacientes que apresentando outras doenças dermatológicas infecciosas. O exame histopatológico (HE) e a IHQ foram realizados em todos os pacientes incluídos neste estudo. Na revisão sistemática, foram encontrados potenciais alvos antigênicos para uso em técnicas imunológicas para o diagnóstico de LT, LC e leishmaniose mucosa (LM). No entanto, a maioria dos estudos são provas de conceito, fato que reforça a necessidade de desenvolvimento de estudos de validação mais abrangentes. Através da técnica de Western blotting e IHQ em lesão de animal experimentalmente infectado, foi comprovada a imunorreatividade dos AcMos anti-mTXNPx e anti-LACK. No estudo de validação empregando AcMos anti-mTXNPx, a maior sensibilidade foi observada para IHQ-FA (85,7%), seguida por IHQ-POD (79,6%), exame direto (77,6%), HE (65,3%) e cultura in vitro (49%). IHQ e HE apresentaram especificidade acima de 90%. A positividade do exame direto e da cultura aumentou significativamente quando os resultados foram combinados com da IHQ-FA, atingindo 95,9% e 93,9%, respectivamente. Através da análise de regressão logística verificamos que as técnicas de IHQ e HE são capazes de detectar pacientes com LC independentemente da carga parasitária. Os resultados obtidos neste estudo demonstram o potencial da técnica de IHQ para o diagnóstico da LC no Brasil e possibilita o desenvolvimento de novas alternativas diagnósticas para o controle dessa doença negligenciada.CAPESTegumentary leishmaniasis (TL) is still a worldwide public health problem, presenting mainly through skin lesions (cutaneous leishmaniasis – CL). In Latin America, most cases occur in Brazil, and several Leishmania species have been associated with human cases. The laboratory diagnosis is crucial and considered one of the pillars to disease control. In this manner, the development and validation of an immunohistochemistry assay (IHC) using monoclonal antibody (mAb) for CL-diagnosis were performed. Firstly, a systematic review identifing potential antigenic targets that have been previously evaluated for TL-immunodiagnosis was performed. Antigens were further selected according specific characteristics and considered potential for CL-diagnosis through IHC. The six selected antigens were: mitochondrial tryparedoxin peroxidase (mTXNPx); Leishmania homologue of activated C kinase (LACK); secreted acid phosphatase (sAcP); kinetoplastid membrane protein-11 (KMP-11); hypothetical protein (LbHP) and Mitogen-activated protein kinase 4 (MAPK4). The amino acid sequences were selected, further synthetized, and inserted in pET28a plasmid by GenScript. Those plasmids were inserted into cloning and expression vectors for the production of recombinant antigens (rAg). The rAgs were used as immunogens in BALB/c mice for mAb production through somatic hybridization. The immunoreactivity of each mAb was tested by Western blotting using soluble antigens of L. amazonensis, L. braziliensis and L. guyanensis. Subsequently, the IHC was performed on skin biopsies from hamsters infected with the same Leishmania species. The standardization and validation of IHC was performed with anti- mTXNPx mAb through two detection systems consisting of polymer with peroxidase enzyme (IHC-HRP) and alkaline phosphatase (IHC-AP). The IHC was validated on skin biopsy from 49 CL-patients diagnosed by clinical examination and real-time quantitative polymerase chain reaction (qPCR). For this group, the direct examination and in vitro culture were also performed. Furthermore, 37 patients presenting other dermatological infectious diseases were included. The histopathology (HE) and IHC were performed for all patients included in the study. A total of 81 antigens were found in the systematic review for the diagnosis of TL, CL and mucosal leishmaniasis (ML). However, a large number of proof-of-concept studies reinforce the need for further studies. In the IHC validation study, the higher sensitivity value was observed for IHC-AP (85.7%), followed by IHC-HRP (79.6%), direct examination (77.6%), HE (65,3%) and in vitro culture (49%). Both IHCs and histopathology presented specificity over 90%. The IHC-AP combined with direct examination enhanced the positivity to 95.9%, and the same IHC combined with HE increased the positivity to 93.9%. The multivariate regression analysis showed that IHC and HE were the only tests able to detect CL-patients regardless the parasite burden. The IHC evaluated here is useful to detect the main Leishmania species causing CL in Brazil and could support the diagnostic strategies for disease control

    RADIS: Comunicação e Saúde, número 223, abril

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    RADIS é uma publicação da Fundação Oswaldo Cruz, editada pelo Programa Radis (Reunião, Análise e Difusão de Informação sobre Saúde), da Escola Nacional de Saúde Pública (Ensp).O texto destaca a grave situação enfrentada pelo Brasil diante da pandemia de covid-19, com um número alarmante de mortes e uma resposta inadequada por parte do governo. O negacionismo e a disseminação de informações falsas têm contribuído para a negligência no combate à doença, bem como para o atraso na disponibilização de vacinas e na adoção de medidas eficazes. Além disso, o texto aponta para outras questões sociais e ambientais que também são negligenciadas, como a desigualdade, o desmatamento e a violência contra minorias. A falta de políticas públicas adequadas agrava ainda mais a situação, deixando milhões de brasileiros em situação de vulnerabilidade. No entanto, apesar dos desafios, o texto ressalta a importância da empatia e do compromisso com a verdade e a ciência. Destaca-se a necessidade de um pacto pela verdade e pela coerência, que oriente uma política de Estado focada na igualdade, no desenvolvimento sustentável e no respeito à vida. Por fim, o texto destaca histórias de esperança e solidariedade, mostrando como as comunidades estão se unindo para enfrentar a crise e apoiar aqueles que mais precisam. Enfatiza-se o papel fundamental do Sistema Único de Saúde (SUS) na distribuição de vacinas e na promoção da saúde em todo o país

    Recovery of Synthetic Zika Virus Based on Rio-U1 Isolate Using a Genetically Stable Two Plasmid System and cDNA Amplification

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    In 2016, the world experienced the unprecedented Zika epidemic. The ZIKV emerged as a major human pathogen due to its association with the impairment of perinatal development and Guillain–Barré syndrome. The occurrence of these severe cases of Zika points to the significance of studies for understanding the molecular determinants of flavivirus pathogenesis. Reverse genetics is a powerful method for studying the replication and determinants of pathogenesis, virulence, and viral attenuation of flaviviruses, facilitating the design of vaccines and therapeutics. However, the main hurdle in the development of infectious clones is the instability of full-length cDNA in Escherichia coli. Here, we described the development of a genetically stable and efficient infectious clone based on the ZIKV Rio-U1 isolated in the 2016 epidemic in Brazil. The employed strategy consisted of cloning the viral cDNA genome into two stable plasmid subclones and obtaining a high-quality cDNA template with increment in DNA mass for in vitro transcription by PCR amplification. The strategy for developing a ZIKV infectious cDNA clone designed in this study was successful, yielding a replicative and efficient clone-derived virus with high similarities with its parental virus, Rio-U1, by comparison of the proliferation capacity in mammal and insect cells. The infection of AG129 immunocompromised mice caused identical mortality rates, with similar disease progression and morbidity in the animals infected with the parental and the cDNA derived virus. Histopathological analyses of mouse brains infected with the parental and the cDNA-derived viruses revealed a similar pathogenesis degree. We observed meningoencephalitis, cellular pyknosis, and neutrophilic invasion adjacent to the choroid plexus and perivascular cuffs with the presence of neutrophils. The developed infectious clone will be a tool for genetic and functional studies in vitro and in vivo to understand viral infection and pathogenesis better

    Fiocruz's interactions with the Legislative to consolidate the CEIS' agenda for COVID-19

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    A pesquisa trata da relação da Fiocruz com o Congresso Nacional tendo como agenda política o Complexo Econômico Industrial da Saúde (CEIS). O objetivo geral é analisar a interface da agenda de desenvolvimento do CEIS com o Poder Legislativo, para tanto, buscou-se explorar as estruturas e processos de relacionamento da Fiocruz com o Congresso Nacional, sistematizar e analisar o papel da Fiocruz e do Poder Legislativo no desenvolvimento do CEIS a partir da resposta à pandemia de covid-19, e propor subsídios para a melhoria da atuação da Fiocruz com o Poder Legislativo no âmbito do CEIS. Foram realizadas entrevistas semiestruturadas com atores-chave do Congresso e da Fiocruz de forma a verificar como se dá o diálogo institucional, bem como análise documental para avaliar a influência do Poder Legislativo Federal no CEIS ao longo do período de estudo e os marcos legais estruturantes de sua conformação. O trabalho parte da visão Schumpteriana sobre inovação, passa pelo Sistema Nacional de Inovação em Saúde para se ater ao CEIS como objeto de estudo e o papel do Legislativo na formulação das políticas públicas que o sustentam. A partir dos resultados identificados foi possível ter uma primeira aproximação de como se dá o relacionamento Fiocruz-Congresso Nacional, discutir o papel tanto da Fiocruz quanto do Congresso no fortalecimento do CEIS e estabelecer propostas concretas de melhoria desta relação de forma a potencializar a capacidade da Fiocruz de contribuir com as políticas públicas do setor.The research addresses Fiocruz's relation with the National Congress having as a political agenda the Health Economic-Industrial Complex (CEIS). The general objective is to analyze the agenda\2019s interface of CEIS´s development with the Legislative Power, to this end, it was sought to explore the structures and process of relationship between Fiocruz and the National Congress, systematize and analyze the role of Fiocruz and the Legislative Power to the progress of CEIS as of the response to the covid-19 pandemic, and propose subsidies to improve Fiocruz's performance with the Legislative Power regarding to the scope of CEIS. Interviews were made with main actors of the Congress and Fiocruz to verify how the institutional dialogue takes place, as well as documental analysis to measure the influence of the federal Legislative Power on CEIS throughout the pandemic and the structuring legal frameworks of its conformation. The research is based on the Schumpterian vision about innovation, passing through the National System of Innovation in Health to stick to the CEIS as an object of study and the role of the Legislative in the creation of public policies that support it. From the results identified, it was possible to have a first approach of how Fiocruz-National Congress relationship takes place, to discuss the role Fiocruz and the Congress have in strengthening the CEIS and establish concrete proposals to improve this connection aiming to enhance Fiocruz\2019s capacity to contribute to public policies in the sector

    Estimating direct costs of the treatment for mucosal leishmaniasis in Brazil

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    INTRODUCTION: The objective of this study was to estimate the direct medical costs of the treatment for mucosal leishmaniasis (ML) using three therapeutic approaches in the Brazilian context. METHODS: We performed this economic assessment from the perspective of the Brazilian public healthcare system. The following therapeutic approaches were evaluated: meglumine antimoniate, liposomal amphotericin B, and miltefosine. Direct medical costs were estimated considering four treatment components: a) drug, b) combined medical products, c) procedures, and d) complementary tests. RESULTS: Treatment with meglumine antimoniate had the lowest average cost per patient (US167.66),followedbymiltefosine(US 167.66), followed by miltefosine (US 259.92) in the outpatient treatment regimen. The average cost of treatment with liposomal amphotericin B was US$ 715.35 both in inpatient regimen. In all estimates, the drugs accounted for more than 60% of the total cost for each treatment approach. CONCLUSIONS: These results demonstrate the marked differences in costs between the therapeutic alternatives for ML. In addition to efficacy rates and costs related to adverse events, our data have the potential to support a complete cost-effectiveness study in the future. Complete analyses comparing costs and benefits for interventions will assist health managers in choosing drugs for ML treatment in Brazil as well as in establishing effective public health policies

    Saúde Amanhã: Textos para Discussão 51: Empresas de Planos de Saúde no Brasil: crise sanitária e estratégias de expansão

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    Publicação cujo objetivo é divulgar resultados de estudos desenvolvidos no âmbito do Projeto Saúde Amanhã, disseminando informações sobre a prospecção estratégica em saúde, em um horizonte móvel de 20 anos. Busca, ainda, estabelecer um espaço para discussões e debates entre os profissionais especializados e instituições do setor. As opiniões emitidas nesta publicação são de exclusiva e de inteira responsabilidade do autor, não exprimindo, necessariamente, o ponto de vista da Fiocruz/MS. O projeto Saúde Amanhã é conduzido pela Fundação Oswaldo Cruz (Fiocruz) no contexto da “Estratégia Fiocruz para a Agenda 2030”/Fiocruz. É permitida a reprodução deste texto e dos dados nele contidos, desde que citada a fonte. Reproduções para fins comerciais são proibidas.Lucas Salvador Andrietta, Universidade de São Paulo, foi convidado pela Fiocruz, para autoria e desenvolvimento do conteúdo do trabalho. Artur Monte-Cardoso, Universidade Federal do Rio de Janeiro, foi convidado pela Fiocruz, para autoria e desenvolvimento do conteúdo do trabalho. Jose Antônio de Freitas Sestelo, Universidade Federal do Rio de Janeiro, foi convidada pela Fiocruz, para autoria e desenvolvimento do conteúdo do trabalho. Mario César Scheffer, Universidade de São Paulo, foi convidado pela Fiocruz, para autoria e desenvolvimento do conteúdo do trabalho. Ligia Bahia, Universidade Federal do Rio de Janeiro, foi convidada pela Fiocruz, para autoria e desenvolvimento do conteúdo do trabalho

    Genetic evidence and host immune response in persons reinfected with SARS-CoV-2, Brazil

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    We thank Carmen Beatriz Wagner and Giacoia Gripp for assessments related to the Biosafety Level 3 facility and Marco Alberto Medeiros for assessments related to the sequencing platform. We thank Gonzalo Bello, Dumith Chequer Bou-Habib, Willian Provance, and Fabiano Thompson for insightful discussions. We greatly appreciated the MGI, a partner in the implementation of next-generation sequencing through collaborations with Oswaldo Cruz Foundation, especially for challenging samples of COVID-19. Author contributions: F.A.B. and P.T.B. conducted clinical surveillance. N.F.R. and F.A.B. enrolled patients in the study. N.F.R., C.Q.S., D.R., I.G.A., V.C.S. performed immunologic assessments. N.F.R., A.P.D.S., M.C.S., F.B.S., M.A.F., J.G., H.J., and H.T. performed sequencing. A.P.D.S., M.C.S., and D.A.T were responsible for bioinformatics. F.A.B., P.T.B., C.M.M., T.M.L.S. handled study coordination. N.F.R., P.T.B., A.MV., and T.M.L.S. prepared and revised the manuscript. All authors revised and approved the manuscript.Mostra que uma primeira exposição à Covid-19 em casos brandos ou assintomáticos pode não produzir resposta imunológica e que a pessoa pode se reinfectar, inclusive, com a mesma variante. A segunda infecção pode provocar sintomas mais fortes do que a primeira. Os dados mostram que para a parcela da população que tem a doença na forma branda (em que não é necessária a hospitalização) isso não significa que fique imune ou que uma reinfecção evolua de forma benigna. O estudo indica ainda que a reinfecção pode ser mais frequente do que se supõe.The dynamics underlying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection remain poorly understood. We identified a small cluster of patients in Brazil who experienced 2 episodes of coronavirus disease (COVID-19) in March and late May 2020. In the first episode, patients manifested an enhanced innate response compared with healthy persons, but neutralizing humoral immunity was not fully achieved. The second episode was associated with different SARS-CoV-2 strains, higher viral loads, and clinical symptoms. Our finding that persons with mild COVID-19 may have controlled SARS-CoV-2 replication without developing detectable humoral immunity suggests that reinfection is more frequent than supposed, but this hypothesis is not well documented

    An updated map of Trypanosoma cruzi histone post-translational modifications

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    In humans and other eukaryotes, histone post-translational modifcations (hPTMs) play an essential role in the epigenetic control of gene expression. In trypanosomatid parasites, conversely, gene regulation occurs mainly atthe post-transcriptional level. However, our group has recently shown that hPTMs are abundant and varied in Trypanosoma cruzi,the etiological agent of Chagas Disease, signaling for possible conserved epigenetic functions. Here, we applied an optimized mass spectrometry-based proteomic workfow to provide a high-confdence comprehensive map of hPTMs, distributed in all canonical, variant and linker histones of T. cruzi. Our work expands the number of known T. cruzi hPTMs by almost 2-fold, representing the largest dataset of hPTMs available to any trypanosomatid to date, and can be used as a basis for functional studies on the dynamic regulation of chromatin by epigenetic mechanisms and the selection of candidates forthe development of epigenetic drugs against trypanosomatids

    Early detection and persistent positivity of anti‑Leishmania antibodies using a recombinant protein‑based ELISA in naturally infected dogs in Brazil

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    Foundation for Research Support of the State of Bahia (Grants JCB0010/2013, SUS0036/2013 and PET0024/2013) and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES)—Finance Code 001.Visceral leishmaniasis (VL) is a zoonotic disease caused by Leishmania infantum, for which dogs constitute the main urban parasite reservoir. Control measures and the treatment of canine visceral leishmaniasis (CVL) are essential to reduce VL cases. Early and accurate detection of L. infantum-infected dogs is crucial to the success of VL control. To improve the serological detection of L. infantum-exposed dogs, we evaluated the early diagnosis capacity of a recombinant protein (rLci5) in an immunosorbent assay (ELISA) to detect naturally infected dogs. Additionally, we evaluated the persistence of the positive results obtained by rLci5 ELISA in comparison to other conventional diagnostic test methods. Methods: Serum samples obtained from 48 L. infantum-infected dogs involved in a cohort study were evaluated using different diagnostic methods (qPCR, EIE-LVC, DPP-LVC and splenic culture). The results were compared to rLci5 ELISA to determine its capacity to diagnose L. infantum infection at earlier infection time points. The persistence of positive diagnostic test results was also compared for each dog evaluated. Results: rLci5 ELISA presented higher rates of positive results at early time points compared to the other diagnostic tests employed in the cohort study, as early as 24 months prior to detection by other tests. rLci5 ELISA positivity was 52.1% (25/48) at baseline, while qPCR was 35.4% (17/48), DPP-LVC 27.1% (13/48), EIE-LVC 22.9% (11/48) and culture only 4.2% (2/48). In at least one of the time points of the 24-month cohort study, rLci5 ELISA was positive in 100% (48/48) of the dogs, versus 83% (40/48) for qPCR, 75% (36/48) for DPP-LVC, 65% (31/48) for EIE-LVC and 31% (15/48) for culture. Investigating clinical signs in association with diagnostic test positivity, rLci5 ELISA successfully detected CVL in 62.9% (95/151) of the clinical evaluations with a score of 0–3, 64.3% (45/70) with scores between 4 and 7, and 73.7% (14/19) with scores > 7, providing higher rates of positivity than all other methods evaluated. Moreover, rLci5 ELISA presented the greatest persistence with respect to test positivity: 45.8% of the dogs evaluated. Conclusion: Four diagnostic tests were compared to rLci5 ELISA, which presented earlier infection diagnosis and a greater persistence of positive test results performance by detecting infected dogs sooner than other testing methods, with enhanced persistence of positive results over the course of the infection

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