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Mechanism and plasticity of vectors' host-seeking behavior
No full textThe host-seeking behavior of disease vector insects is central to the transmission of pathogens. In this context, an improved understanding of the mechanisms that allow vectors to detect, identify and locate a potential host will be crucial to refine existing control strategies and invent new ones. Host-seeking is mediated by the integration of cues that are processed by multiple sensory modalities, and provide robust information about host location and quality. Responses to these cues are plastic and vary as a function of the vector’s internal state, age, and previous experience. Vectors also integrate other factors such as time of day, or even the level of defensiveness of the host. Here, we review the most recent advances on the molecular basis of host-seeking behavior, with a particular emphasis on disease vector mosquitoes
Conditional Cash Transfer Program and Leprosy Incidence: Analysis of 12.9 Million Families From the 100 Million Brazilian Cohort (Preprint)
No full textCONFAP/ESRC/MRC/BBSRC/CNPq/FAPDF–Doencas Negligenciadas
(FAP-DF 193.000.008/2016), the UK Medical Research Council (MR/N017250/1), the Wellcome Trust
(202912/B/16/Z), and CAPES.Leprosy is a neglected tropical disease predominately affecting poor and marginalized populations. To test the hypothesis that poverty-alleviating policies may be associated with reduced leprosy incidence, we evaluated the association between the Brazilian Bolsa Familia conditional cash transfer Program (BFP) and new leprosy case detection using linked records from 12,949,730 families in the 100 Million Brazilian Cohort (2007-2014). After propensity score matching BFP beneficiary to non-beneficiary families, we used Mantel-Haenszel tests and Poisson regressions to estimate incidence rate ratios (IRRs) for new leprosy case detection and secondary endpoints related to operational classification and leprosy-associated disabilities at diagnosis. Overall, cumulative leprosy incidence was 17.4/100,000 pyr (95%CI: 17.1, 17.7), and markedly higher in "priority" (high-burden) versus "non-priority" (low-burden) municipalities (22.8/100,000 pyr, 95%CI: 22.2, 23.3 versus 14.3/100,000, 95%CI: 14.0, 14.7). After matching, BFP participation was not associated with leprosy incidence overall (IRRPoisson 0.97, 95%CI: 0.90, 1.04) but was associated with lower leprosy incidence when restricted to families living in high-burden municipalities (IRRPoisson 0.86, 95%CI: 0.77, 0.96). In high-burden municipalities, the association was particularly pronounced for paucibacillary cases (IRRPoisson 0.82, 95%CI: 0.68, 0.98) and cases with leprosy-associated disabilities (IRRPoisson 0.79, 95%CI: 0.65, 0.97). These findings provide policy-relevant evidence that social policies may contribute to on-going leprosy control efforts in high-burden communities
Personal data usage and privacy considerations in the COVID-19 global pandemic
No full textDados ganham cada vez mais importância e valor na busca de respostas para enfrentar a COVID-19 tanto para a ciência quanto para as autoridades sanitárias. Em virtude da dificuldade de realizar diagnóstico da infecção na população em geral, iniciativas apoiadas em tecnologias digitais vêm sendo desenvolvidas por governos ou empresas privadas para possibilitar rastreamentos de sintomas, contatos e deslocamentos de modo a apoiar estratégias de acompanhamento e avaliação na vigilância de contágios. A despeito da importância e necessidade dessas iniciativas, questionamentos acerca da quantidade e tipos de dados pessoais coletados, processados, compartilhados e utilizados em nome da saúde pública, bem como os concomitantes ou posteriores usos desses dados, suscitam questionamentos éticos, legais e técnicos. Desafios que apontam para a necessidade de novos modelos de governança de dados e de tecnologias, responsáveis e transparentes, para controlar o Sars-Cov2 e as futuras emergências de saúde pública.Data has become increasingly important and valuable for both scientists and health authorities searching for answers to the COVID-19 crisis. Due to difficulties in diagnosing this infection in populations around the world, initiatives supported by digital technologies are being developed by governments and private companies to enable the tracking of the public's symptoms, contacts and movements. Considering the current scenario, initiatives designed to support infection surveillance and monitoring are essential and necessary. Nonetheless, ethical, legal and technical questions abound regarding the amount and types of personal data being collected, processed, shared and used in the name of public health, as well as the concomitant or posterior use of this data. These challenges demonstrate the need for new models of responsible and transparent data and technology governance in efforts to control SARS-COV2, as well as in future public health emergencies
Pan-Drug Resistant Acinetobacter baumannii, but Not Other Strains, Are Resistant to the Bee Venom Peptide Melittin
No full textAcinetobacter baumannii is a prevalent pathogen in hospital settings with increasing importance in infections associated with biofilm production. Due to a rapid increase in its drug resistance and the failure of commonly available antibiotics to treat A. baumannii infections, this bacterium has become a critical public health issue. For these multi-drug resistant A. baumannii, polymyxin antibiotics are considered the only option for the treatment of severe infections. Concerning, several polymyxin-resistant A. baumannii strains have been isolated over the last few years. This study utilized pan drug-resistant (PDR) strains of A. baumannii isolated in Brazil, along with susceptible (S) and extreme drug-resistant (XDR) strains in order to evaluate the in vitro activity of melittin, an antimicrobial peptide, in comparison to polymyxin and another antibiotic, imipenem. From a broth microdilution method, the determined minimum inhibitory concentration showed that S and XDR strains were susceptible to melittin. In contrast, PDR A. baumannii was resistant to all treatments. Treatment with the peptide was also observed to inhibit biofilm formation of a susceptible strain and appeared to cause permanent membrane damage. A subpopulation of PDR showed membrane damage, however, it was not sufficient to stop bacterial growth, suggesting that alterations involved with antibiotic resistance could also influence melittin resistance. Presumably, mutations in the PDR that have arisen to confer resistance to widely used therapeutics also confer resistance to melittin. Our results demonstrate the potential of melittin to be used in the control of bacterial infections and suggest that antimicrobial peptides can serve as the basis for the development of new treatments
Effectiveness of generic direct-acting agents for the treatment of hepatitis C: systematic review and meta-analysis
No full textObjective: To compare the efficacy of generic direct-acting agents and brand-name medicines for treating hepatitis C virus (HCV) infection by conducting a systematic review and meta-analysis. Methods: We searched online databases for studies that reported sustained virological responses 12 weeks after the end of HCV treatment with generic direct-acting agents. We derived pooled proportions of treated patients with a sustained virological response from intentionto-treat and per-protocol analyses. In addition, we calculated the pooled relative risk (RR) of a sustained virological response brand-name versus generic direct-acting agents using a random-effects model (DerSimonian–Laird) from the data available. Between-study heterogeneity was assessed using the I 2 statistic. Findings: We identified 19 studies involving a total of 57 433 individuals from eight territories or regions. The pooled overall proportions of patients with a sustained virological response were 98% (95% confidence interval, CI: 97–99; 18 studies; I 2=94.1%) in per-protocol analyses and 96% (95% CI: 93–98; 8 studies; I 2=68.1%) in intention-to-treat analyses. The likelihood of a sustained virological response with brandname medicines was similar to that with generic direct-acting agents (RR: 1.00; 95% CI: 0.98–1.02; I 2=0.0%). The likelihood of a sustained virological response was significantly higher in patients without than with cirrhosis (RR:1.03; 95% CI: 1.01–1.06; 7 studies) but was not significantly affected by either previous treatment (3 studies) or human immunodeficiency virus coinfection (3 studies). Conclusion: Generic direct-acting agents are highly effective for treating hepatitis C. Generic agents should be considered in resourceconstrained settings for decreasing the burden of liver disease in HCV-infected patients.Comparar la eficacia de los antivirales genéricos de acción directa y los medicamentos de marca para el tratamiento de la infección por el virus de la hepatitis C (VHC) mediante la realización de una revisión sistemática y un metaanálisis.Comparer l’efficacité des antiviraux à action directe génériques et des médicaments de marque pour traiter l'infection par le virus de l’hépatite C (VHC) à l’aide d’une revue systématique et d’une méta-analyse
Aplicação da técnica de amplificação isotérmica em alça (LAMP) para o diagnóstico da Leishmaniose visceral
No full textA Leishmaniose Visceral (LV) é uma infecção causada por protozoários do complexo Leishmania donovani, no Brasil o agente etiológico é a espécie Leishmania infantum, e encontra-se entre as seis endemias consideradas prioritárias no mundo. O diagnóstico precoce desta parasitose é de grande importância, pois quando não tratados ou tratados tardiamente os casos têm maior letalidade. A visualização do parasito em amostras de punção de medula óssea é definida como método de diagnóstico padrão ouro, entretanto, é considerado um procedimento invasivo e necessita de ambiente adequado e profissionais capacitados. A técnica de Amplificação Isotérmica em Alça (LAMP) é um teste molecular de amplificação de DNA que não requer o uso de termocicladores, podendo ser realizado em banho-maria, pois toda a reação acontece a uma temperatura constante. Tendo em vista todas as vantagens do método LAMP, este estudo propôs a otimização e aplicação desta técnica para diagnóstico da LV em indivíduos residentes no município de Tamandaré, no estado de Pernambuco. Nesta pesquisa, foram coletadas amostras de sangue periférico de 83 indivíduos residentes do município em questão. Nos ensaios de otimização do LAMP foi avaliada a sensibilidade, sendo possível detectar o DNA de Leishmania infantum até a concentração de 100ag e, nos ensaios de especificidade, apenas amostras contendo DNA de Leishmania infantum foram positivas. Quando o sistema LAMP foi aplicado para o diagnóstico da LV nas amostras coletadas, não houve resultados positivos. Na aplicação da Reação em Cadeira da Polimerase (PCR) utilizando o sistema ITS1 para diagnóstico da LV, todos os pacientes também foram negativos. A partir desta pesquisa, o sistema de LAMP pode ser considerado sensível e específico para detecção molecular de DNA de Leishmania infantum no Brasil. Estudos posteriores aplicando amostras clínicas positivas são necessários afim de definir a sensibilidade e especificidade analítica deste sistema .The Visceral Leishmaniasis (VL) is an infection caused by protozoa from the Leishmania donovani complex and is among the six endemic diseases considered to be priority in the world. The early diagnosis of this parasitosis is of great importance, because when untreated or treated late, the cases are more lethal. The visualization of the parasite in bone marrow puncture samples is defined as a gold standard diagnostic method, however, it is considered an invasive procedure and requires an adequate environment and trained professionals. The Loop Isothermal Amplification (LAMP) technique is a molecular DNA amplification test that does not require the use of thermocyclers, and can be performed in a water bath, as the entire reaction takes place at a constant temperature. In view of all the advantages of the LAMP method, this study proposed the optimization and application of this technique for the diagnosis of VL in individuals living in the municipality of Tamandaré, in the state of Pernambuco. In this research, peripheral blood samples were collected from 83 individuals living in the municipality in question. In the LAMP optimization assays the sensitivity was evaluated, being possible to detect the Leishmania infantum DNA up to the concentration of 100 ag and, in the specificity tests, only samples containing Leishmania infantum DNA were positive. When the LAMP system was applied for the diagnosis of VL in the collected samples, there were no positive results. In the application of the Polymerase Chair Reaction (PCR) using the ITS1 system for the diagnosis of VL, all patients were also negative. From this research, the LAMP system can be considered sensitive and specific for molecular detection of Leishmania infantum DNA in Brazil. Further studies using positive clinical samples are necessary in order to define the sensitivity and analytical specificity of this system
Avaliação da eutanásia de cães soro reagentes para leishmaniose visceral canina como único método de controle da doença em área enzoótica no Centro Oeste de Minas Gerais
No full textA Leishmaniose visceral humana (LV) está em franca expansão e distribuída nas cinco regiões geográficas do Brasil, o Nordeste sendo a região em que há o maior número de casos registrados. O principal reservatório urbano do agente etiológico da LV é o cão doméstico e sabe-se que casos caninos antecedem o aparecimento de casos humanos. Uma das ações de controle da LV, preconizada pelo Ministério da Saúde, é a eutanásia dos cães soro reagentes. Em 2013, no município de Iguatama/MG, foi realizado o primeiro inquérito sorológico canino na cidade, sendo constatada uma prevalência de 8,3% de cães soro reagentes para Leishmania infantum. Dos animais com sorologia positiva para Leishmaniose visceral canina (LVC), neste inquérito, 84% foram eutanasiados e 16% foram a óbito em, no máximo, dois anos após o diagnóstico. Nenhuma outra medida de controle para LVC foi realizada no município. Os objetivos deste estudo foram determinar a prevalência atual de cães soro reagentes para LVC no município de Iguatama e observar o impacto das eutanásias de cães soro reagentes para LV como única medida de controle realizada neste município, considerado área enzoótica para a doença. Para isso, foi realizado um novo inquérito epidemiológico canino no município de Iguatama, seguindo as normas do Manual de Vigilância e Controle da Leishmaniose Visceral. Foram colhidas amostras sanguíneas de 270 cães que foram examinadas pelo teste imunocromatográfico DPP® e pelo ensaio imunoenzimático (ELISA). Os animais que apresentaram resultados inconclusivos tiveram novas amostras de sangue coletadas e analisadas. O único animal que apresentou resultado positivo no DPP® e indeterminado no ELISA, na primeira avaliação, soro converteu quatro meses depois, o que reforça a recomendação do Ministério da Saúde de reavaliar os cães que apresentam resultado inconclusivo para LVC. Do total das 270 amostras, 21 foram reagentes nos dois testes. Portanto, a prevalência de cães soro reagentes para LVC, em 2017, na área urbana do município de Iguatama foi igual a 7,8%. A infecção pela espécie Leishmania infantum foi confirmada através da técnica molecular de PCR-RFLP em 10 cães amostrados com sorologia positiva para LVC. A comparação entre a prevalência atual (depois das eutanásias) com a encontrada em 2013 (8,3%), não mostrou diferença significativa (p=0,764). Uma vez que a soro prevalência de LVC na área urbana do município de Iguatama ainda é alta, pode-se supor que a eutanásia dos cães soro reagentes para LVC, somada à ausência de monitoramento e de outras medidas de intervenção, não contribuiu para a diminuição da transmissão do parasito, e não foi suficiente para o controle de LVC no município de Iguatama, uma área considerada, até 2013, indene para LVC.of Brazil, with the Northeast being the region that presents the most significant number of registered cases. The main urban reservoir of the etiological agent of VL is the domestic dog, and it is known that canine cases precede human cases. One of the control actions of VL, recommended by the Ministry of Health, is performing the euthanasia of seropositive dogs. In 2013, in the municipality of Iguatama/MG, the first canine serological survey was carried out in the city, with a prevalence of 8.3% of seropositive dogs for Leishmania infantum. Of the seropositive animals for Canine Visceral Leishmaniasis (CVL) in this survey, 84% were euthanized, and 16% died within two years after diagnosis. No other control measures for CVL were taken in the municipality. The objectives of the present study were to determine the current prevalence of seropositive dogs for CVL in the municipality of Iguatama and to observe the impact of euthanasia of seropositive dogs to VL as the only control measure performed in this municipality, which is considered an enzootic area of the disease. For this, a new canine epidemiological survey was carried out in the municipality of Iguatama, following the guidelines of the Manual of Surveillance and Control of Visceral Leishmaniasis. Blood samples were collected from 270 dogs and tested by DPP® immunochromatographic test and by Enzyme-Linked Immunosorbent Assay (ELISA). The animals that presented inconclusive results had new blood samples collected and analyzed. The only animal that showed a positive result in DPP® and undetermined in the ELISA, in the first evaluation, became seropositive four months later, so this study reinforces the recommendation of the Ministry of Health to reassess dogs that present inconclusive results for CVL. From a total of 270 samples, 21 (7.8%) were reagents in both tests. Thus, the prevalence of seropositive dogs for CVL, in 2017, in the urban area of the municipality of Iguatama was 7.8%. The Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) molecular technique confirmed infection by L. infantum in the ten dogs sampled with CVL-positive serology. The comparison between the current prevalence (after euthanasia) with that found in 2013 (8.3%), there was no significant difference (p=0.764). The prevalence of CVL in the urban area of the municipality of Iguatama is still high, making it possible to presume that the euthanasia of seropositive dogs for CVL, and the absence of monitoring or other interventions measures, did not contribute to decrease the transmission of the parasite and was not sufficient for the control of CVL in the municipality of Iguatama, an area considered as non-endemic to CVL until 2013
Introdução à Citometria de Fluxo: Um manual básico para iniciantes
No full textA citometria de fluxo é uma tecnologia que cada vez mais tem se destacado no laboratório clínico e de pesquisa sendo responsável por diversos avanços na ciência. Sua aplicação não se limita a uma única área do conhecimento, podendo ser empregada nas áreas de imunologia, hematologia, genética, biologia celular, microbiologia, parasitologia, oceanografia, em estudos de novos medicamentos e de terapias com células tronco, entre muitos outros. Baseia-se na mensuração dos parâmetros morfológicos e funcionais de
células, por meio da detecção da dispersão da luz e da emissão da fluorescência de corantes ligados à superfície ou ao interior dessas células, quando são interceptadas por uma fonte luminosa, como um laser. Sua capacidade para analisar diversos parâmetros simultaneamente em uma única célula, torna a citometria de fluxo no método de escolha para análises multiparamétricas de populações celulares. Além de ser uma técnica também aplicada na separação ou purificação de uma determinada população celular a partir de uma suspenção heterogênea, processo denominado de sorting. Por ser uma metodologia com todas estas importantes características e abrangência de aplicações e, ao mesmo tempo, carecer de manuais mais básicos e introdutórios escritos em língua portuguesa; este pequeno livro veio para suprir esta lacuna e tentar ajudar estudantes de graduação e pós-graduação, bem como cientistas que não terão que operar diretamente um citômetro de fluxo, mas precisarão de um conhecimento básico na leitura de artigos que apresentem
resultados desta técnica, além de uma orientação inicial para identificarem se precisarão utilizá-la ou não no andamento de suas pesquisas
Preservation of audiovisual files: evaluation of the aplicability of Archivematica
No full textO entendimento teórico sobre o que os repositórios digitais se propõem a preservar vem do aprendizado prático de uso e interpretação das ações geradas por esses softwares cada vez mais indispensáveis. A preservação de documentos audiovisuais e suas especificidades, sobretudo a variedade de formatos físicos, formatos digitais de contêineres e codecs, assim como seu alto volume de dados faz com que esse gênero documental mereça uma atenção diferenciada no seu tratamento arquivístico de preservação. O trabalho aqui proposto utilizou como ferramenta de preservação a ser testada o repositório Archivematica na versão 1.9.1, no contexto do seu uso prático para tratamento de documentos audiovisuais que compõem o acervo da VideoSaúde – Distribuidora (VSD) da Fiocruz. Os resultados obtidos foram descritos e avaliados quanto a sua capacidade de criação de pacotes de informação de submissão (SIP), geração de pacotes de informação de arquivamento (AIP) e interpretação de metadados METS dos AIP. Nesse sentido, concluiu-se que a estrutura dos SIP elaborados para teste no software atendeu aos parâmetros de processamento para geração de AIP completos e robustos. Entretanto, destaca-se que testes com outros formatos e abordando outras especificidades de vídeo devem ser pesquisados para complementação da análise sobre o uso da ferramenta frente à preservação digital de documentos audiovisuais.The use of repositories to preserve digital documents is based on the recommendations of the Open Archival Information System (OAIS) reference model and is consolidated as a fundamental part of technological solutions for maintaining the authenticity of digital archival documents. The theoretical understanding of what these preservation repositories propose to accomplish comes from the practical learning of using and interpreting the actions generated by these increasingly indispensable software. The preservation of audiovisual documents and their specificities, especially the variety of physical formats, digital formats of containers and codecs, as well as its high volume of data makes this documentary genre merit a differentiated attention in its archival preservation treatment. The work proposed here used the Archivematica repository in version 1.9.1 as a preservation tool to be tested, in the context of its practical use for processing audiovisual documents that make up the collection of VideoSaúde – Distribuidora (VSD) of Fiocruz. Digital preservation literature and software documentation were consulted to support the development of the tests. The results obtained were described and evaluated for their ability to create submission information packages (SIP), generation of archival information packages (AIP) and interpretation of AIP METS metadata. In this sense, it was concluded that the structure of the SIP designed for testing in the software met the processing parameters for generating complete and robust AIP. However, it is highlighted that tests with other formats and addressing other specificities of video should be researched and / or carried out to complement the analysis on the use of the tool in view of the digital preservation of audiovisual documents
Modulation of antibiotic resistance by the essential oil of Ocimum gratissimum L. in association with light-emitting diodes (LED) lights
No full textCentro Universitário Dr. Leão Sampaio (Unileão)Universidade Regional do Cariri (URCA)This study aimed to evaluate the antibacterial and antibiotic-enhancing effects of the essential oil obtained from Ocimum gratissimum L. (OEOg) alone or in association with light-emitting diodes (LED) lights. The essential oil was obtained by hydrodistillation and its chemical composition analysed by gas chromatography coupled to mass spectrometry. The antibacterial and antibiotic-enhancing activities against multiresistant strains of Staphylococcus aureus and Escherichia coli were evaluated by the gaseous contact method. The analysis of the photoinductive effect on the antibacterial activity of the OEOg and antibiotics was assessed through exposure to different LED lights (red, blue and yellow). The phytochemical analysis identified five compounds, including eugenol, as the major constituent. The OEOg caused a significant inhibition of the halo, indicating a direct antibacterial effect. Exposure to the LED lights significantly enhanced the activity of the OEOg against E. coli. On the other hand, the action of the essential oil against S. aureus was enhanced by exposure to both blue and yellow lights. The effects of LED light exposure on the activity of conventional antibiotics varied significantly according to the drug and the bacterial strain. However, most combinations of LED lights and the OEOg presented synergistic effects against resistant bacterial strains, indicating enhanced antibacterial activity. Thus, these in vitro findings suggest that both OEOg and LED lights have promising antibacterial effects. Nevertheless, further research is required to evaluate in vivo the potential of these therapies for the treatment of infectious skin diseases