Changes in the seroprevalence and risk factors between the first and second waves of COVID-19 in a metropolis in the Brazilian Amazon.

In Brazil, the coronavirus disease 2019 (COVID-19) epidemic spread rapidly in a heterogeneous way, mainly due to the different socioeconomic and behavioral characteristics of different regional populations and different evaluation periods. We performed a cross-sectional study including 1,337 individuals (first wave = 736/second wave = 601) after the first two waves of COVID-19 in the city of Belém, the capital of the state of Pará. The detection of IgG anti-SARS-CoV-2 antibodies was performed using an enzyme-linked immunosorbent assay test followed by statistical analysis using the RStudio program. Our results showed an increase in the seroprevalence (first wave= 39.1%/second wave= 50.1%) of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG antibodies in the population of Belém from the first to the second pandemic wave. Advanced age, primary or secondary education level, lack of social isolation, and a low frequency of protective mask use were considered risk factors for SARS-CoV-2 infection during the first wave compared to the second wave. This study is one of the firsts to provide important information about the dynamics of virus circulation and the groups vulnerable to exposure in the two major periods. Our data emphasize the socioeconomic characteristics of the affected population and that nonpharmacological prevention measures are crucial for combating the pandemic.

Seroprevalence and risk factors for COVID-19 in the metropolis of the Brazilian Amazon.

The devastating effect of health system overload was observed after cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) peaked in April 2020 in Belém, a capital metropolis in the Brazilian Amazon. Our results showed a high seroprevalence (39.24%) of anti-SARS-CoV-2 IgG antibodies among the population of the capital of the state of Pará after the first wave of the pandemic. Old age, mixed race, a high school education level, low income and contact with infected individuals are risk factors and may be driving seropositivity and exposure to SARS-CoV-2 in this population. This study is one of the first to provide important information to understand the socioeconomic inequalities, behavioral characteristics and viral transmission dynamics associated with the risk of SARS-CoV-2 infection in the capital of the state of Pará, northern Brazil.

Biodegradability and nutrients release of thermoplastic starch and poly (ε-caprolactone) blends for agricultural uses.

Driven by the environmental stress caused by plastics, the interest on eco-friendly polymers has attracted the attention of researchers and industry. Thermoplastic starch (TPS) and poly (ε-caprolactone) (PCL) blends are good examples of sustainable material, exhibiting synergism between economic viability and properties. However, its biodegradability aligned to nutrients release has been less explored in agricultural applications. Herein, it is proposed the investigation of biodegradability of urea plasticized TPS and PCL blends, compatibilized with PCL grafted with maleic anhydride (PCL-g-MA), aiming fertilizers and sustainable agricultural products. The blends were prepared in a twin-screw extruder using a flat film die. The mechanical, thermal, morphological, and physical properties of TPS-PCL films were characterized, including biodegradation analysis via Bartha respirometer and nitrogen release in the soil. The films presented biodegradability and nitrogen release as a function of TPS content on blends formulation, presenting flexibility and robust mechanical properties. These findings may open a way of multifunctional agricultural products applied as fertilizer materials through economical and sustainable mulching films.

Cellulose Nanocrystals from Fibers of Macauba (Acrocomia Aculeata) and Gravata (Bromelia Balansae) from Brazilian Pantanal.

Cellulose nanocrystals (CNC) were obtained from macauba and gravata fibers. Macauba (or Bocaiuva) is a palm tree found throughout most of Brazil and Gravata is an abundant kind of bromelia with 1-2m long leaves, found in Brazilian Pantanal and Cerrado. The raw fibers of both fibers were mercerized with NaOH solutions and bleached; they were then submitted to acid hydrolysis using H2SO4 at 45 °C, varying the hydrolysis time from 15 up to 75 min. The fibers were analyzed by X-ray diffraction (XRD), FTIR Spectroscopy, scanning electron microscopy (SEM) and thermal stability by thermogravimetric analysis (TG). XRD patterns did not present changes in the crystal structure of cellulose after mercerization, but it was observed a decrease of hemicellulose and lignin contents, and consequently an increase of cellulose content with the increase of NaOH solution concentration in the mercerization. After acid hydrolysis, the cellulose nanocrystals (CNC) were also analyzed by transmission electron microscopy (TEM) which showed an acicular or rod-like aspect and nanometric dimensions of CNC from both fibers, but the higher values of aspect ratio (L/D) were found on CNC obtained from gravata after 45 min of acid hydrolysis. The mercerization and subsequent bleaching of fibers influenced the crystallinity index and thermal stability of the resulting CNC, but their properties are mainly influenced by the hydrolysis time, i. e., there is an increase in crystallinity and thermal stability up to 45 min of hydrolysis, after this time, both properties decrease, probably due to the cellulose degradation by the sulfuric acid.

Fatores de risco para mortalidade em idosos admitidos em unidade de terapia intensiva de hospital público / Risk factors for mortality in geriatric patients admitted to the intensive care unit at a public hospital

OBJETIVO: Avaliar fatores de risco para mortalidade em pacientes idosos com internação em uma unidade de terapia intensiva (UTI). MÉTODOS: Foram estudados pacientes idosos admitidos em UTI, em um estudo de coorte histórica. Foi realizada amostragem de conveniência de todos os pacientes com 60 anos ou mais, internados nos 20 leitos de uma UTI de um hospital de alta complexidade. Foi realizada análise de regressão de Cox para estimar os fatores de risco associados à mortalidade. O nível de significância utilizado foi de 5%. RESULTADOS: A proporção de pacientes idosos representou 45% das admissões em UTI no período. A mortalidade hospitalar foi de 38,4%. A variável pós-operatório de cirurgia de urgência e os escores Acute Physiology and Chronic Health Evaluation (APACHE II) e Sequential Organ Failure Assessment (SOFA) da admissão foram identificados como fatores de risco independentes para mortalidade hospitalar. CONCLUSÃO: Os fatores de risco associados à mortalidade foram os escores APACHE II e SOFA da admissão e pós-operatório de cirurgia de urgência.

OBJECTIVE: To evaluate risk factors for mortality in geriatric patients admitted to an intensive care unit (ICU). METHODS: We studied older patients admitted to the ICU in a historical cohort study. Convenience sampling was performed for all patients aged 60 years or older, admitted to the 20 beds of an ICU of a highly complex hospital. Cox regression analysis was performed to estimate risk factors associated with mortality. The significance level used was 5%. RESULTS: The proportion of geriatric patients represented 45% of ICU admissions in the period. In-hospital mortality was 38.4%. The postoperative emergency surgery variable and the Acute Physiology and Chronic Health Evaluation (APACHE II) and Sequential Organ Failure Assessment (SOFA) admission scores were identified as independent risk factors for in-hospital mortality. CONCLUSION: Risk factors associated with mortality were APACHE II and SOFA scores for admission and postoperative emergency surgery.

Curaua and eucalyptus nanofibers films by continuous casting: Mechanical and thermal properties.

A wide variety of new green materials such as curaua leaf fibers (CLFs) has potential applications in nanotechnology. This study aims to investigate the thermomechanical properties and morphological structure of cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) films obtained by continuous casting. The CNCs were obtained by acid hydrolysis and CNFs by mechanical shearing from bleached CLFs and eucalyptus pulp. The morphology after continuous casting resulted in oriented nanofibers, and as a consequence there was mechanical anisotropy. CNCs films showed the greatest values of tensile strength (36±4MPa) and the more effective fibrillation provided better mechanical strength of eucalyptus CNFs films than curaua CNFs films. Sulfur groups and mechanical shear degradation affected the stability of CNCs and CNFs films, respectively. Thus, the type of nanostructure, the way they interact to each other, the cellulose source and the process interfere significantly on the properties of the films.

Bionanocomposites produced from cassava starch and oil palm mesocarp cellulose nanowhiskers.

Cassava starch films reinforced with cellulose nanowhiskers from oil palm mesocarp fibers were produced by casting. Nanowhiskers were obtained by sulphuric acid hydrolysis followed by microfluidization and incorporated in starch films at various loadings (1-10wt%). Morphological and mechanical characterizations showed that the reinforcing effect of oil palm cellulose nanowhiskers was significant at loadings of up to 6wt%, which was determined to be the nanowhiskers percolation threshold. Above this content, formation of agglomerates became more significant, causing a decrease in mechanical properties of starch bionanocomposites. Below percolation threshold, such as 2wt%, elongation at break increased by 70%, showing an effective reinforcing effect. Dynamic mechanical analyses revealed filler/matrix interactions through hydrogen bonding in bionanocomposites.

Biodegradable blends of urea plasticized thermoplastic starch (UTPS) and poly(ε-caprolactone) (PCL): Morphological, rheological, thermal and mechanical properties.

Biodegradable blends of urea plasticized thermoplastic starch (UTPS) and poly(ε-caprolactone) (PCL) were prepared in a co-rotating twin screw extruder. The UTPS and PCL content varied in a range of 25wt%. The materials were characterized by capillary rheometry, scanning electron microscopy (SEM), termogravimetry (TGA), differential scanning calorimetry (DSC) and tensile tests. Capillary rheometry showed better interaction between UTPS and PCL at 110°C than at 130°C. SEM showed immiscibility of all blends and good dispersion of UTPS in PCL matrix up to 50wt%. However, a co-continuous morphology was found for UTPS/PCL 75/25. Thermal analysis showed that introducing PCL in UTPS, increased Tonset due to higher thermal stability of PCL, and blends presented an intermediate behavior of neat polymers. The presence of PCL in blends improved significantly the mechanical properties of neat UTPS. Because they are totally biodegradable, these blends can be vehicles for controlled or slow release of nutrients to the soil while degraded.

Sodium Thiosulfate for Recovery of Bond Strength to Dentin Treated with Sodium Hypochlorite.

INTRODUCTION: The aim of this study was to evaluate the efficacy of sodium thiosulfate (Na2S2O3) for restoring adhesion to pulp chamber dentin treated with sodium hypochlorite (NaOCl) and EDTA. METHODS: Sixty-three crowns of bovine incisors were cut to expose the dentin pulp chamber. The specimens were polished and randomly distributed into 9 groups (n = 7) according to the following protocols used: 0.9% sodium chloride for 30 minutes (negative control), 5.25% NaOCl for 30 minutes, 17% EDTA for 3 minutes, and 5.25% NaOCl for 1 minute (positive control). The other groups, after treatments with NaOCl and EDTA, were immersed in 0.5% or 5% Na2S2O3 for 1, 5, and 10 minutes or just immersed in an inert solution for 10 minutes (0.9% sodium chloride). After drying the specimens, Scotchbond Multi-Purpose (3M ESPE, St Paul, MN) was applied to the pulp chamber dentin followed by Filtek Z250 composite (3M ESPE). Six rectangular slabs were obtained from each specimen, and the dentin/resin interface was tested by using a universal testing machine. The resulting data were submitted to 1-way analysis of variance and the Duncan test (P = .05). RESULTS: There was a significant decrease in bond strength regarding NaOCl and EDTA (P < .05). When 5% Na2S2O3 was used for 10 minutes, the bond strength was found to be statistically equal to the negative control and higher than the positive control (P < .05). CONCLUSIONS: The use of Na2S2O3 can significantly increase the bond strength of composite resin to NaOCl/EDTA-treated dentin, allowing adhesive restorations to be immediately applied after endodontic treatment.

Evaluation of the genotoxicity of cellulose nanofibers.

BACKGROUND: Agricultural products and by products provide the primary materials for a variety of technological applications in diverse industrial sectors. Agro-industrial wastes, such as cotton and curaua fibers, are used to prepare nanofibers for use in thermoplastic films, where they are combined with polymeric matrices, and in biomedical applications such as tissue engineering, amongst other applications. The development of products containing nanofibers offers a promising alternative for the use of agricultural products, adding value to the chains of production. However, the emergence of new nanotechnological products demands that their risks to human health and the environment be evaluated. This has resulted in the creation of the new area of nanotoxicology, which addresses the toxicological aspects of these materials. PURPOSE AND METHODS: Contributing to these developments, the present work involved a genotoxicological study of different nanofibers, employing chromosomal aberration and comet assays, as well as cytogenetic and molecular analyses, to obtain preliminary information concerning nanofiber safety. The methodology consisted of exposure of Allium cepa roots, and animal cell cultures (lymphocytes and fibroblasts), to different types of nanofibers. Negative controls, without nanofibers present in the medium, were used for comparison. RESULTS: The nanofibers induced different responses according to the cell type used. In plant cells, the most genotoxic nanofibers were those derived from green, white, and brown cotton, and curaua, while genotoxicity in animal cells was observed using nanofibers from brown cotton and curaua. An important finding was that ruby cotton nanofibers did not cause any significant DNA breaks in the cell types employed. CONCLUSION: This work demonstrates the feasibility of determining the genotoxic potential of nanofibers derived from plant cellulose to obtain information vital both for the future usage of these materials in agribusiness and for an understanding of their environmental impacts.

Efeitos da temperatura e do tempo de armazenamento na estabilidade química de soluções de hipoclorito de sódio / Effects of temperature and storage time on the stability of sodium hypochlorite solutions

Introdução: Nas últimas décadas, a Endodontia teve um grande avanço tecnológico e, dentre as mudanças nessa evolução, reduziu-se significativamente o tempo necessário para o preparo do canal radicular. Nesse contexto, soluções cada vez mais concentradas de hipoclorito de sódio (NaOCl) começaram a ser utilizadas. Objetivo: O  objetivo do presente trabalho foi avaliar os efeitos da temperatura e do tempo de armazenamento na estabilidade química de soluções de hipoclorito de sódio a 8% em diferentes pHs, comparando esses possíveis efeitos com aqueles relativos às concentrações comumente encontradas no mercado. Material e método: Soluções de NaOCl nas concentrações de 1%; 2,5%; 5,25% e 8% foram manipuladas com valores de pH 7 e 10,4. As amostras foram armazenadas à temperatura ambiente e em geladeira, tendo sido avaliadas após 1, 2 e 3 meses de armazenamento. Após os diferentes tempos experimentais, as amostras tiveram sua concentração determinada. A concentração de cloro ativo das soluções foi determinada por titulação, método da iodometria. Os dados foram avaliados estatisticamente. Resultado: Os resultados mostraram que o armazenamento da solução em geladeira, comparado àquele em temperatura ambiente, reduziu a perda de cloro ativo em todas as concentrações avaliadas e que, nestas diferentes concentrações, houve a perda do teor de cloro com o passar do tempo. Conclusão: As soluções de NaOCl a 8% mostraram-se mais instáveis à temperatura ambiente, quando comparadas àquelas armazenadas em geladeira, do que as demais concentrações avaliadas. A temperatura e o tempo de armazenamento afetaram a estabilidade química de todas as concentrações avaliadas.

Introduction: In recent decades, endodontics had great technological advances that have significantly reduced the time required for root canal preparation. In this context, increasingly concentrated sodium hypochlorite (NaOCl) solutions have been used. Objective: The aim of this study was to evaluate the effects of temperature and storage time on chemical stability of 8% sodium hypochlorite solutions, at different pHs, comparing with usual concentrations. Material and method: 1%, 2.5%, 5.25% and 8% NaOCl solutions, at pH 7 and 10.4 were manipulated. Paired samples were stored at room temperature and in a refrigerator and were evaluated after 1, 2 and 3 months of storage. After the different experimental times, the NaOCl concentration was determined. The active chlorine concentration of the NaOCl solutions was determined by iodometric titration. The data were statistically analyzed. Result: When the solution was stored in refrigerator, compared to room temperature, there was reduced loss of active chlorine in all tested concentrations. Over time there was loss of chlorine content in all solutions. Conclusion: 8% NaOCl solutions were more unstable than other concentrations tested at ambient temperature, as compared to those stored in the refrigerator. The temperature and storage time affected the chemical stability of all concentrations tested.

Conhecimentos, atitudes e práticas sobre o câncer de próstata em Juiz de Fora (MG) / Knowledge, attitudes and practices related to prostate cancer in the city of Juiz de Fora, State of Minas Gerais

Apesar dos esforços do Instituto Nacional de Câncer (Inca) para definir a incidência do câncer de próstata no Brasil, os números produzidos provavelmente situam-se abaixo da realidade. Os homens historicamente buscam menos os cuidados de saúde do que as mulheres. A adesão às praticas de rastreamento do câncer de próstata pode se constituir em um importante marcador do autocuidado masculino em saúde. O estudo objetivou analisar a associação entre conhecimentos, atitudes e práticas acerca da detecção do câncer de próstata. Foi realizado inquérito domiciliar em amostra de 160 homens com idade entre 50 e 80 anos residentes em uma área adscrita da Estratégia Saúde da Família (ESF) do município de Juiz de Fora (MG). Entre os homens classificados com conhecimento adequado, encontrou-se prevalência 7,6 vezes (IC95%=2,4-23,6) mais elevada de serem classificados com prática adequada do que entre aqueles classificados com conhecimento inadequado. Além disso, aqueles classificados com atitudes adequadas tiveram prevalência quase duas vezes mais elevada (RP=1,8; IC=1,1-3,0) de serem classificados com práticas adequadas quando comparados com aqueles com atitudes inadequadas. Evidenciou-se a relevância de se abordar e compreender o conhecimento dos entrevistados sobre câncer de próstata. Desse modo, sensibilizados pela temática, os profissionais da saúde poderão contribuir para a melhoria da assistência de enfermagem aos homens em geral.

Role-playing: estratégia inovadora na capacitação docente para o processo tutorial / Role-playing: an innovative strategy for training teachers for the tutorial process / Role-playing: estrategia innovadora en la capacitación docente para el proceso de tutoría

A análise dos formatos de avaliação do Programa de Desenvolvimento Docente (PDD) da faculdade de Medicina de Marilia, SP, mostra as seguintes fragilidades: baixa motivação, atitude passiva dos participantes e pouco interesse em capacitação para o processo tutorial. Considerando a necessidade de inovação das estratégias de capacitação docente, optou-se, nas oficinas, pelo uso da técnica de role-playing, a qual possibilita a troca de papéis e o aprender na ação. Analisou-se qualitativamente o discurso docente frente ao uso do role-playing nas oficinas desenvolvidas, segundo as narrativas dos formatos de avaliação aplicados. Os núcleos de sentido das respostas foram classificados em unidades temáticas. Os resultados demonstraram a relevância das atividades e que o role-playing foi um importante instrumento facilitador do processo de aprendizagem, à medida que colocou o tutor como protagonista, no papel de estudante, favorecendo novos olhares e percepções e sensibilizando-o para o processo tutorial.

Analysis on assessment formats of the Teaching Development Program (TDP) of Marília Medical School with regard to continuing education shows the following weaknesses: poor motivation, passive attitudes among participants and little interest in training for the tutorial process. Given the need for innovative strategies for teacher training, it was decided to use role-playing techniques in workshops. This enabled exchanges of roles and learning in action. The teacher's discourse relating to the use of role-playing in the workshops developed was qualitatively analyzed according to the narratives of the assessment formats applied. The core meanings of the responses were classified into thematic units. The results demonstrated that these activities were relevant and that role-playing was an important facilitator of the learning process insofar as the tutor was placed as a protagonist for the students' roles, thereby encouraging new perspectives and perceptions and sensitizing students towards the tutorial process.

El análisis de los formatos de evaluación del Programa de Desarrollo Docente (PDD) da facultad de medicina de la ciudad de Marília, referente a la educación continuada muestra las fragilidades siguientes: baja motivación, actitud pasiva de los participantes y poco interés en la capacitación para el proceso de tutoría. Considerando la necesidad de innovación de las estrategias de capacitación docente, en las oficinas se opta por el uso de la técnica de "role playing" que hace posible el cambio de papeles y el aprendizaje en la acción. Se ha analiza cualitativamente el discurso docente ante el uso del "role playing" en las oficinas desarrolladas según las narrativas de los formatos de avaliación aplicados. Los núcleos de sentido las respuestas se han clasificado en unidades temáticas. Los resultados demuestran la importancia de estas actividades y que el "role playing" ha sido un importante instrumento facilitador del proceso de aprendizaje a medida en que colocan al tutor como protagonista, en el papel de estudiante, favoreciendo nuevas miradas y percepciones, sensibilizándole para el proceso de tutoría.

Eficácia de localizadores apicais na identificação de perfurações de diferentes diâmetros / Efficacy of apex locators in the identification of different diameters perforations

Introdução: O objetivo deste estudo in vitro foi avaliar a precisão dos localizadores apicais eletrônicos (LAEs) Novapex® e Root ZX II® na detecção de perfurações radiculares simuladas. Metodologia: Após a remoção da porção coronária de 35 dentes, perfurações artificiais foram realizadas no terço médio com brocas de diferentes diâmetros (01, 04, 08). Os dentes foram então divididos em quatro grupos: três grupos experimentais, com dez dentes, e o grupo de controle, com cinco dentes. Todos foram embebidos em solução salina 0,9% e as determinações eletrônicas da localização das perfurações foram realizadas com os LAEs. Uma lima 10 tipo K foi inserida nos canais até que os LAEs indicassem que tivesse atingido a marca de 0. Logo após, os cursores foram ajustados em uma referência externa. Três medidas foram tomadas para cada dente e obtida uma média. Resultados: Os resultados mostram que o maior diâmetro da perfuração aumentou a sensibilidade LAEs na localização das perfurações. Para comparação de medidas reais com as medidas fornecidas pelo LAE, nos casos em que os LAEs foram capazes de localizar a perfuração, o teste t de student foi utilizado (p < 0,05), não apresentando diferença estatisticamente significante en-tre as diferentes perfurações e os diferentes LAEs. Con-clusão: Os LAEs testados foram precisos e confiáveis na determinação de perfurações de raiz, sendo capazes de auxiliar no diagnóstico clínico desta patologia.

Prevalência de depressão na doença de Parkinson: [revisão] / Prevalence of depression in Parkinson's disease: [review]

CONTEXTO: O reconhecimento da prevalência da depressão em pacientes com doença de Parkinson (DP) é necessário para o desenvolvimento de práticas direcionadas ao tratamento da depressão e a melhora na qualidade de vida deles. OBJETIVO: Identificar na literatura indexada estudos relacionados à prevalência de depressão na DP, visto que normalmente há sub-reconhecimento e subdiagnóstico da comorbidade. MÉTODOS: Levantamento de artigos no PubMed, LILACS e SciELO que cumpriram com as palavras-chave: prevalence, depression e Parkinson. Critérios para inclusão: artigos nos idiomas inglês, português e espanhol, sem limite de tempo. Excluíram-se artigos relacionados ao tratamento da DP e validação de escalas. RESULTADOS: Selecionaram-se 20 artigos com taxas de prevalência de depressão de 1,8 por cento a 68,1 por cento. Seis estudos foram casos-controle, dois foram coortes, um, longitudinal prospectivo e 13, transversais. Quanto à técnica de avaliação, oito empregaram entrevista clínica, nove utilizaram apenas instrumentos de auto-avaliação, um empregou entrevista clínica e instrumentos de auto-avaliação e quatro consultaram bancos de dados. CONCLUSÕES: A prevalência de depressão variou de acordo com a metodologia, porém, em geral, as taxas foram bastante elevadas. Evidenciou-se a necessidade de definições mais precisas sobre depressão na DP para se estabelecer uma taxa de prevalência mais acurada.

BACKGROUND: The recognition of depression prevalence in Parkinson's disease (PD) is necessary for the development of treatment techniques as well as the improvement in the patient's quality of life. OBJECTIVE: To identify in the literature studies related to the prevalence of depression in PD. METHODS: The search for articles was based on PubMed, LILACS and SciELO matching the key-words prevalence, depression and Parkinson. Inclusion criteria of articles were: papers in English, Portuguese and Spanish; without time limitation. Articles related to the treatment of PD and to the validation of scales were excluded. RESULTS: A total of 20 studies were selected, including six case-control studies, 3 longitudinal (2 cohort) studies, and 43 non-sectional studies. Prevalence rates ranged from 1.8 percent to 68.1 percent. Concerning the evaluation of techniques employed, eight studies used clinical interviews, nine used just self-report instruments, one utilized clinical interviews and self-report instruments and four consulted data bases. DISCUSSION: The prevalence of depression varied according to the methodology, however, in general, rates proved to be considerably elevated. The analysis reveals the necessity of more precise and consensual definitions regarding depression in PD so that more accurate prevalence rates can be obtained.