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A review on nanostructured silver as a basic ingredient in medicine: physicochemical parameters and characterization
No full textEstudos recentes com nanopartículas de prata (AgNPs) e a história do metal prata como agente bactericida e virucida de amplo espectro, colocam a prata como um dos futuros candidatos biocidas no campo da nanomedicina para eliminar bactérias e vírus, principalmente os multirresistentes. Nesta revisão, descrevemos as várias morfologias de AgNPs e correlacionamos a atividade bactericida aprimorada com suas facetas {111} proeminentes. Além de priorizar a caracterização também discutimos a importância de quantificar AgNPs e conteúdo de íons de prata (Ag+) e seus diferentes mecanismos nos níveis químico, biológico, farmacológico e toxicológico. O mecanismo de ação das AgNPs contra várias bactérias e vírus, incluindo o SARSCoV-2, foi analisado a fim de entender sua eficácia como agente antimicrobiano com eficácia terapêutica e baixa toxicidade. Além disso, há a necessidade de caracterizar AgNPs e quantificar o conteúdo de Ag+ livre para a implementação de novos estudos sistemáticos desse promissor agente na nanomedicina e na prática clínica.Recent studies with silver nanoparticles (AgNPs) and the history of silver metal as a broad-spectrum bactericidal and virucidal agent, places silver as one of the future biocidal candidates in the field of nanomedicine to eliminate bacteria and viruses, especially multidrug resistant ones. In this review, we have described the various morphologies of AgNPs and correlated the enhanced bactericidal activity with their prominent {111} facets. In addition to prioritizing the characterization we have also discussed the importance of quantifying AgNPs and silver ion content (Ag+) and their different mechanisms at the chemical, biological, pharmacological, and toxicological levels. The mechanism of action of AgNPs against various bacteria and viruses including the SARSCoV-2 was analyzed in order to understand its effectiveness as an antimicrobial agent with therapeutic efficacy and low toxicity. Further, there is the need to characterize AgNPs and quantify the content of free Ag+ for the implementation of new systematic studies of this promising agent in nanomedicine and in clinical practice
Association between water and sanitation and soil-transmitted helminthiases: Analysis of the Brazilian National Survey of Prevalence (2011–2015)
No full textBackground: Most of the studies conducted in Brazil assessing the relationship between water, sanitation and hygiene (WASH) and Soil-transmitted helminth (STH) infections, have focused on cases, reflecting the reality of small areas and not of a countrywide situation. In order to fill this gap, the current paper presents an epidemiological study exploring the association between water and sanitation and STHs prevalence in students from 7 to 17 years old, in all 27 Brazilian Federation Units. Methods: Three ecological studies were carried out considering the prevalence of ascariasis, trichuriasis, and hookworm as outcome variables. The sample consisted of 197,567 students aged 7–17 years old living in 521 Brazilian municipalities. Data were retrieved from the National Survey on the Prevalence of Schistosomiasis mansoni and Soil-transmitted helminth infections (2011–2015). The Generalized Linear Model with the negative binomial distribution was used to evaluate the statistical association between outcomes and explanatory variables. Univariate and Multivariate analyses were conducted with 25 and 5 % significance levels, respectively. Data were aggregated considering municipalities as the geographical unit for analysis. Results: Protective association was found between access to filtered water and adequate sanitation in schools with ascariasis (RR 0.989, CI 95 % 0.983–0.996; RR 0.988, CI 95 % 0.977–0.998), access to filtered water in schools with trichuriasis (RR 0.986, CI 95 % 0.979–0.993) and adequate sanitation at home with hookworm ((RR 0.989, CI 95 % 0.982–0.996). The percentage of population served with Bolsa Família Program, used as a proxy for poverty, was the only significant variable common to all models. Conclusions: Our findings support that WASH, both in schools and homes, are essential to schoolchildren health with regard to STHs. However, sanitary interventions will not be fully effective in preventing STH infections without promoting access to quality public services, particularly for people living in poverty, the most vulnerable group
Avaliação do efeito do Roundup® original em Biomphalaria glabrata
No full textO presente estudo teve como
objetivo avaliar a ação do Roundup® original sobre o molusco Biomphalaria glabrata, infectado e não infectado
por Schistosoma mansoni, observando a mortalidade e a biologia reprodutiva. Os caramujos foram submetidos
às concentrações aquosas: 0,1; 0,09; 0,08; 0,07; 0,06; 0,05; 0,04; 0,03; 0,02, 0,018; 0,016; 0,014; 0,012 e 0,01
(%) do Roundup Original® para a determinação da CL50, sendo essa concentração testada durante 30 dias
sobre os moluscos. Para a observação da atividade reprodutiva frente à exposição ao agrotóxico, quatro grupos
de B.glabrata foram formados: infectados e expostos ao agrotóxicos, infectados e não expostos (controle),
não infectados e expostos e não infectados e não expostos (controle). A CL50 (0,012% da solução aquosa do
Roundup original) apresentou mortalidade que não ultrapassou 95%, 24, 48 e 72 h de exposição durante os 30
dias e perdendo totalmente o efeito após o 27º dia de teste. A atividade reprodutiva de caramujos não infectados
e expostos foi de 30,3 ± 20,5 ovos em 2,7 ± 1,2 massas ovígeras, sendo observada redução de 51% na média de
moluscos eclodidos (11,5 ± 7,5) em comparação ao grupo controle (23,9 ± 18,0) ao longo de quatro semanas
(p = 0,003). Os resultados indicam que a concentração letal (CL50) da solução aquosa 0,012% do Roundup
Original tem ação significativa sobre B. glabrata durante 27 dias. O Roundup diminui significativamente a
fertilidade dos moluscos infectados e expostos em comparação com o grupo controle.The objective of this work is to evaluate the action of original Roundup® on the snail Biomphalaria
glabrata infected and not infected by Schistosoma mansoni by observing its mortality and reproductive biology.
Snails were submitted for 30 days to aqueous solutions of original Roundup at concentrations of 0.1, 0.09,
0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, 0.018, 0.016, 0.014, 0.012 and 0.01 (%) to determine LC50. To analyze the reproductive activity of B. glabrata, against the pesticide, four B. glabrata groups were formed: infected
and exposed to the pesticide; infected and not exposed (control); not infected and exposed; and not infected
and not exposed(control). LC50 (0.012% aqueous solution of original Roundup) caused mortality of at most up
to 95% for 24, 48 and 72 h during the experimental period (30 days), and lost effect totally after 27 days. The
reproductive activity of the non-infected and exposed snails was 30.3 ± 20.5 eggs in 2.7 ± 1.2 egg masses, and
there was a reduction of 51% in the average number of hatched snails (11.5 ± 7.5) in comparison to the control
group (23.9 ± 18.0) for four weeks (p = 0.003). The results indicate that the lethal concentration (LC50) of
the 0.012% aqueous solution of original Roundup has a significant action on Biomphalaria glabrata for up to
27 days. Roundup significantly diminished the fertility of infected and exposed snails in comparison with the
control group
Love or risk? Reflecting on meanings, regulations and prescriptions around breast milk, through “crossnursing” episodes
No full textNeste artigo refletimos sobre os sentidos atribuídos ao leite materno, e os diferentes atores e mecanismos morais que orientam e regulam a prática da amamentação. Nosso foco é a “amamentação cruzada”, ato em que um bebê é amamentado por alguém que não sua própria mãe – contraindicado pelo Ministério da Saúde pelo risco de transmissão de doenças. A partir da análise de materiais diversos, como reportagens e postagens em redes sociais, observamos como casos de amamentação cruzada repercutem a partir de um “script”, em que profissionais de saúde alertam para tais riscos, ao mesmo tempo que atestam a segurança dos bancos de leite, onde o leite doado é pasteurizado. Assim, analisamos ambiguidades em torno do leite e da amamentação, chamando atenção para os processos históricos de estabelecimento dos bancos de leite no Brasil. Por fim, à luz das discussões sobre cuidado, debatemos diferentes modos de vivenciar família, maternidade e amamentação.In this article we explore the meanings attributed to breastmilk, and the different actors and moral mechanisms that guide and regulate the practice of breastfeeding in Brazil. Our focus is “cross-nursing”, an act in which a baby is breastfed by someone other than his own mother – contraindicated by the Ministry of Health, due to the risk of disease transmission. From the analysis of various materials, such as reports and posts on social networks, we observe how cases of cross-nursing resonate from a “script”, in which healthcare professionals warn of such risks, while attesting to the safety of human milk banks, where donated milk is pasteurized. Thus, we analyzed ambiguities around breast milk and breastfeeding, drawing attention to the historical processes of establishing human milk banks in Brazil. Finally, in the light of discussions about care, we discussed different ways of experiencing family, motherhood and breastfeeding
Atuação De Estados E Capitais No Enfrentamento À Violência Contra As Mulheres No Contexto Da COVID-19 No Brasil
No full textO artigo buscou identificar as ações de enfrentamento à violência contra mulheres desenvolvidas por governos estaduais e das capitais no Brasil, no contexto do distanciamento social devido à COVI-19. Para isso, utilizamos o Portal da Transparência para envio do questionamento às secretarias responsáveis pela pasta de políticas para as mulheres, Polícia Civil e Polícia Militar. Utilizamos a análise temática para identificação dos núcleos de sentido das respostas, organizadas de acordo com as categorias: ‘combate’; ‘assistência’; ‘prevenção’; ‘acesso e garantia de direitos’; e ‘gestão e monitoramento da política’. Identificamos uma variedade de ações reportadas na categoria ‘assistência’, mas que corresponderam à adaptação do funcionamento dos serviços já existentes. Na categoria ‘combate’, foram relatadas inovações, cuja eficácia e desafios na implementação devem ser avaliados para o planejamento do seu uso a longo prazo.The paper aims to identify actions to combat violence against women developed by state and capital governments in Brazil, in the context of social distancing due to COVID-19. We used the Transparency Portal to send the question to the secretariats responsible for the policies for women ́s rights, Civil Police and Military Police. We used thematic analysis to identify the core meanings of the responses, organized according to the categories: ‘combat’; ‘assistance’; ‘prevention’; ‘access and guarantee of rights’; and ‘policy management and monitoring’. We identified a variety of actions reported in the ‘assistance’ category, but which corresponded to adapting the functioning of existing services. In the ‘combat’ category, innovations have been reported, whose effectiveness and implementation challenges must be assessed for planning their long-term use
Meios de Cultura: apresentação geral
No full textdubladoVídeo sobre Meio de Cultura: Apresentação geralFiocruzMP4Tópicos em Cultura de Células de MamíferosPrograma de Pós-Graduação em Biociências e Biotecnologi
Saúde Amanhã: Textos para Discussão 72: Fatores ambientais e epidemiologia das doenças crônicas
No full textPublicação 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
Escenas del discurso de la pandemia de Covid-19: el discurso del aislamiento social en la prensa
No full textWedencley Alves Santana da Universidade Federal de Juiz de Fora, da Faculdade de Comunicação Social teve seu artigo submetido e aprovado na edição da RECIIS - Dossiê Comunicação, Saúde e Crises Globais: parte 2 v. 15 n.1 (2021)Michele Nacif Antunes da Universidade Federal do Espírito Santo, da Pró-Reitoria de Pesquisa e Pós-Graduação, do Programa de Pós-Graduação em Saúde Coletiva teve seu artigo submetido e aprovado na edição da RECIIS - Dossiê Comunicação, Saúde e Crises Globais: parte 2 v. 15 n.1 (2021)O presente artigo tem como objetivo analisar discursos do/no jornal O Globo, um veículo de referência no jornalismo brasileiro, sobre a estratégia de isolamento social como forma de contenção da pandemia de Covid-19. Para isso, tomou como base de observação e análise notícias e reportagens publicadas pelo jornal durante as duas primeiras semanas de medidas (do dia 16 ao dia 26 do mês de março de 2020). O estudo partiu da Análise de Discurso (Pêcheux/Orlandi) para compreender se houve deslocamentos de sentido em relação às medidas e aos embates discursivos que tiveram lugar entre autoridades políticas, de saúde e a própria população. O artigo conclui que mais do que produzir sentido sobre a cena discursiva que se instaurou durante esse período, o próprio jornal se fez ator nessa cena, participando de intrigas discursivas que nela tiveram lugar.This article aims to analyze discourses by/in the newspaper O Globo, a reference vehicle in Brazilian journalism, about the strategy of social isolation as a way of containing the Covid-19 pandemic. For this purpose, it took as a base of observation and analysis news and reports published by the newspaper during the first two weeks of measures (from March 16to 26). The study started from Discourse Analysis (Pêcheux/Orlandi) to understand if there have been displacements of meanings in relation to measures and the discursive clashes that took place between political, health authorities and the population itself. The article concludes that more than producing meaning about the discursive scene that was established during that period, the newspaper itself became an actor in that scene, participating in the discursive intrigues that took place on it.Este artículo tiene como objetivo analizar los discursos del diario O Globo, vehículo de referencia en el periodismo brasileño, sobre la estrategia de aislamiento social como forma de contener la pandemia Covid-19. Para ello, tomó como base de observación y análisis las noticias e informes publicados por el diario durante las primeras dos semanas de medidas (del 16 al 26 de marzo). El estudio partió del Análisis del Discurso (Pêcheux/Orlandi) para entender si hubo algún desplazamiento de sentidos con relación a las medidas y los enfrentamientos discursivos que se produjeron entre las autoridades políticas, sanitarias y la propia población. El artículo concluye que más que producir significado sobre la escena discursiva que se instauró durante ese período, el propio diario se convirtió en actor de esa escena, participando de las intrigas discursivas que se desarrollaban en ella
Triggering the proboscis extension reflex (PER) in Rhodnius prolixus
No full textThe heat emitted by the host body constitutes a short distance orientation cue for most blood-sucking insects, as is the case of the kissing-bug Rhodnius prolixus. We evaluated here how kissing bugs assess the distance to a warm target, in order to reach it by displaying the Proboscis Extension Reflex (PER). We confronted blind-folded insects to a thermal source either at 35° or at 40 °C under both, open- and closed-loop conditions. The results showed that nymphs were able to estimate the distance to a thermal source just using thermal information. Free walking insects displayed PER with a maximum frequency at 5 mm from the object, even without touching it. Yet, our experiments showed that the insects need to walk freely to estimate the distance to the source accurately, i.e. performing the PER at a distance allowing them to reach the target with the tip of the proboscis. The distance at which PER was triggered was independent of the temperature of the thermal source (35° or 40 °C). Moreover, our results also unravelled that mechanical stimuli can be integrated with thermal cues, being capable of affecting the triggering of PER in kissing bugs. This is the first study providing evidence that blood-sucking vector insects use mechanoreception for eliciting their bites. We discuss our findings in the light of present models explaining the ability of kissing bugs to estimate the distance and the temperature of a potential food sources
Origin and evolution of nonulosonic acid synthases and their relationship with bacterial pathogenicity revealed by a large-scale phylogenetic analysis
No full textNonulosonic acids (NulOs) are a group of nine-carbon monosaccharides with different functions in nature. N-acetylneuraminic acid (Neu5Ac) is the most common NulO. It covers the membrane surface of all human cells and is a central molecule in the process of self-recognition via SIGLECS receptors. Some pathogenic bacteria escape the immune system by copying the sialylation of the host cell membrane. Neu5Ac production in these bacteria is catalysed by the enzyme NeuB. Some bacteria can also produce other NulOs named pseudaminic and legionaminic acids, through the NeuB homologues PseI and LegI, respectively. In Opisthokonta eukaryotes, the biosynthesis of Neu5Ac is catalysed by the enzyme NanS. In this study, we used publicly available data of sequences of NulOs synthases to investigate its distribution within the three domains of life and its relationship with pathogenic bacteria. We mined the KEGG database and found 425 NeuB sequences. Most NeuB sequences (58.74%) from the KEGG orthology database were classified as from environmental bacteria; however, sequences from pathogenic bacteria showed higher conservation and prevalence of a specific domain named SAF. Using the HMM profile we identified 13941 NulO synthase sequences in UniProt. Phylogenetic analysis of these sequences showed that the synthases were divided into three main groups that can be related to the lifestyle of these bacteria: (I) predominantly environmental, (II) intermediate and (III) predominantly pathogenic. NeuB was widely distributed in the groups. However, LegI and PseI were more concentrated in groups II and III, respectively. We also found that PseI appeared later in the evolutionary process, derived from NeuB. We use this same methodology to retrieve sialic acid synthase sequences from Archaea and Eukarya. A large-scale phylogenetic analysis showed that while the Archaea sequences are spread across the tree, the eukaryotic NanS sequences were grouped in a specific branch in group II. None of the bacterial NanS sequences grouped with the eukaryotic branch. The analysis of conserved residues showed that the synthases of Archaea and Eukarya present a mutation in one of the three catalytic residues, an E134D change, related to a Neisseria meningitidis reference sequence. We also found that the conservation profile is higher between NeuB of pathogenic bacteria and NanS of eukaryotes than between NeuB of environmental bacteria and NanS of eukaryotes. Our large-scale analysis brings new perspectives on the evolution of NulOs synthases, suggesting their presence in the last common universal ancestor