Isolated specific IgA against respiratory viruses, Influenza or SARS-CoV-2, present in the saliva of a fraction of healthy and asymptomatic volunteers

Objectives: Defense against respiratory viruses depends on an immune response present in the mucosa, as saliva IgA secretes antibodies. During the pandemic, such as influenza or SARS-CoV-2, most infected patients are asymptomatic but retain specific antibodies post-infection. The authors evaluated IgG and IgA antibodies against SARS-CoV-2 and influenza in the saliva of asymptomatic volunteers, validated with controls or vaccinated individuals. Methods: The authors detected specific antibodies by validated conventional ELISA using natural SARS-CoV-2 antigens from infected Vero cells or capture-ELISA for influenza using natural antigens of the influenza vaccine. Results: Saliva from influenza-vaccinated individuals had more IgA than paired serum, contrary to the findings for specific IgG. In COVID-19-vaccinated samples, specific IgA in saliva increased after vaccination, but IgG levels were high after the first dose. In saliva from the asymptomatic population (226), anti-Influenza IgG was found in 57.5% (130) of samples, higher than IgA, found in 35% (79) of samples. IgA results were similar for SARS-CoV-2, with IgA present in 30% (68) of samples, while IgG was less present, in 44.2% (100) of samples. The proportion of influenza IgG responders was higher than that for SARS-CoV-2 IgG, but both populations presented similar proportions of IgA responders, possibly due to variable memory B cell survival. For both viruses, the authors found an important proportion (> 10%) of IgA+IgG- samples, suggesting the occurrence of humoral immunity directed to the mucosa. Conclusion: Specific antibodies for respiratory viruses in saliva are found in either infection or vaccination and are a convenient and sensitive diagnostic tool for host immune response

Produção de um bioplástico a partir da Fécula da Mandioca com propriedades antifúngicas

Atualmente as embalagens de plástico convencionais são utilizadas em larga escala. Nos supermercados e padarias, para armazenamento de pães, bolos, dentre outros alimentos, essas embalagens são a escolha padrão. Porém, o plástico tradicional, além de causar um impacto negativo no meio ambiente, devido sua demora para se decompor, também não protege os alimentos da contaminação por microrganismos como os fungos. Logo, com a população se tornando mais consciente e sustentável, faz-se necessário a busca por maneiras alternativas para produção de embalagens biodegradáveis. Em vista disso, o projeto proposto tem como finalidade a produção de um bioplástico a partir da fécula de mandioca, que tenha ação antifúngica, por meio do uso de um ácido orgânico, utilizando a metodologia de Casting para produção de filmes plásticos. Assim nos estudos preliminares foi possível confeccionar o bioplástico com qualidade e propriedades físicas que adequam seu uso para o objetivo proposto. Entretanto, por se tratar de um projeto em andamento, as propriedades antifúngicas ainda estão sendo determinadas. Conclui-se que é possível obter um plástico sustentável e econômico, com características desejáveis para o uso comercial. Estudos posteriores, será verificado se o produto tem eficiência antifúngica, tornando a embalagem uma alternativa viável para substituir as embalagens convencionais

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Epidemiologic study of rabies virus in wild mammals from a release area, North coast of São Paulo State, Brazil.

A crescente importância do ciclo silvestre da raiva envolvendo morcegos e mamíferos terrestres demonstra a importância do estudo da epidemiologia do vírus da raiva nessas espécies. Foram estudadas amostras provenientes de diversas espécies de animais silvestres terrestres procedentes de uma área de Mata Atlântica nativa no litoral Norte do Estado de São Paulo. Este estudo pesquisou a presença de anticorpos contra o vírus da raiva por meio dos Testes de RFFIT, SFIMT e ELISA em amostras de soro de animais capturados em uma área desmatada, transpostos e monitorados em uma área de soltura. E ainda a pesquisa do vírus da raiva por meio das técnicas de IFD, IC e RT-PCR em amostras de sistema nervoso central dos animais encontrados mortos na região. A positividade observada foi de 10,8% na RFFIT, 34,0% no SFIMT e 1,13% no ELISA. Todos as amostras submetidas as técnicas de IFD, IC e RT-PCR apresentaram resultados negativos. Os resultados observados demonstram circulação do vírus entre as espécies silvestres da área.The emergent importance of rabies in terrestrial wild animals demonstrates the importance of epidemiological studies regarding rabies virus in those animal species. Samples from several wild species from a native Rainforest area in the North coast of São Paulo State Brazil were studied. The aim of the present study was the research of anti-rabies antibodies in those animals using the RFFIT, SFIMT and ELISA techniques in animals captured and monitorated in a release área. And also by rabies virus detection using FAT, MIT and RT-PCR techniques in central nervous system samples from animals found dead in the same area. The observed positivity was 10,8% on RFFIT, 34,0% on SFIMT e 1,13% on ELISA. All samples tested by the FAT, MIT and RT-PCR techniques presented negative results. The observed results are an evidence of rabies virus circulation between wild animal species in the studied area

Avaliação da reação em cadeia pela polimerase (PCR) para a detecção do vírus rábico em amostras animais armazenadas por diferentes períodos e submetidas à decomposição

A utilização de métodos sensíveis e específicos para o diagnóstico da raiva constitui uma importante ferramenta para o controle e profilaxia dessa enfermidade. A Reação em Cadeia pela Polimerase através de Transcriptase-Reversa (RT-PCR) tem sido utilizada com bons resultados no diagnóstico do vírus rábico, mesmo quando as amostras estão em estágio de decomposição. Adicionalmente as técnicas moleculares têm sido utilizadas para estudos epidemiológicos possibilitando um melhor conhecimento da epidemiologia viral. O presente trabalho teve como objetivo avaliar as técnicas de RT-PCR e hnRT-PCR para a detecção do vírus rábico em estudos retrospectivos, para isso foram avaliadas 101 amostras cerebrais de diferentes espécies animais armazenadas por diferentes períodos, recém-descongeladas e mantidas em temperatura ambiente por 72 horas para decomposição. Os resultados das técnicas de RT-PCR e hnRT-PCR foram comparados com resultados prévios da Imunofluorescência Direta (IFD) e Inoculação Intracerebral em Camundongos (IC). Das 50 amostras positivas testadas, 26 (52%) apresentaram resultados positivos para a RT-PCR e 45 (90%) com a associação da hnRT-PCR quando realizadas em amostras recentemente descongeladas. Das amostras em decomposição foram analisadas 48 previamente positivas; onde 17 (34,3%) apresentaram resultado positivo para a RT-PCR e 36 (75%) com a associação da hnRT-PCR. Não foram encontrados resultados falso-positivos nas amostras negativas submetidas às técnicas de biologia molecular. A hnRT-PCR apresentou maior sensibilidade em relação à RT-PCR nas amostras recém-descongeladas e em decomposição. Os resultados sugerem a viabilidade de sua aplicação em estudos retrospectivos em materiais descongelados e decompostos.The use of methods, both sensitive and specific, for rabies diagnosis are important tools for the control and prophylaxis of the disease. Reverse-Transcriptase Polymerse Chain Reaction (RT-PCR) has been used in rabies diagnosis with good results, even in decomposed materials. Additionally, molecular techniques have been used for epidemiological studies and better knowledge of viral epidemiology. The aim of this work was to evaluate the RT-PCR and hnRT-PCR in rabies virus detection in retrospectives studies. RT-PCR and hnRT-PCR were evaluated in 151 brain samples from different animal species, thawed and left at room temperature for 72 hours for decomposition. The RT-PCR and hnRT-PCR results were compared with preview results from Fluorescent Antibody Test and Mouse Inoculation Test. From the 50 positive fresh samples, 26 (52%) were positive for RT-PCR and 45 (90%) for hnRT-PCR. From the 48 positive decomposed samples, 17 (34, 3%) were positive for RT-PCR and 36 (75%) for hnRT-PCR. No false-positives results were found in the negatives samples submitted to the molecular techniques. These results show that the hnRT-PCR was more sensitive than RT-PCR, and both techniques presented lower sensibility in decomposed samples. The hnRT-PCR presented greater sensibility than the standards techniques (IFD e IC) in decomposed materials for rabies diagnosis. These results suggest the viability of the application of molecular techniques in thawed and decomposed materials for retrospective studies

Knowledge, Attitudes and Practices Regarding Sylvatic Rabies among High-Risk Households in Ceará State, Brazil

Rabies transmitted by sylvatic populations has become an increasing concern in Brazil. A total of 113 participants with a history of contact with sylvatic populations were interviewed in 27 municipalities of Ceará State in northeast Brazil. Questionnaires included questions on knowledge, attitudes and practices (KAP) regarding sylvatic rabies. Most of the respondents (92%) knew about rabies and confirmed at least one species that transmitted the disease (79.6%). Of these respondents, 69% mentioned monkeys, and 67.2% mentioned dogs. However, 16% of the respondents listed an incorrect species. In general, knowledge on the symptoms and signs and on prevention measures was weak. The majority raised pets (93.8%), most commonly dogs and cats, and, of all the pets, 85.7% were claimed to be vaccinated against rabies. A total of 67.3% reported the appearance of free-living wild animals around their houses, mostly marmosets and wild canids; 18.3% reported that sylvatic populations had attacked animals or humans. Seventy-three percent had raised or still were raising wild animals as pets, mostly capuchin monkeys (79.5%) and marmosets (24.1%). This is the first KAP study on sylvatic rabies in Brazil. The data indicate important knowledge gaps and risk behavior within a high-risk population. There is a need for strengthening and improving sylvatic rabies surveillance and control, combined with the intensification of education and information campaigns