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This paper evaluates linear and nonlinear regression analysis to describe the empirical adsorption kinetics using pseudo-first-order (PFO) and pseudo-second-order (PSO) models. These models have been used to characterize the performance of adsorbents for environmental remediation and environmental modeling. Data were simulated using the PFO and PSO models with 1, 2, and 5% noise levels and fitted by nonlinear and linearized PFO and PSO equations. Nonlinear regression analysis provided rate constants and adsorption capacities with better accuracy than linearization. Besides the correlation coefficient, Chi-square and residual plot analysis helped choose the proper model to describe the adsorbent efficiency and validate the results. Both models and the NLR fitting were employed to reevaluate data obtained in our research group, including the adsorption of Hg(II) on thiol-modified vermiculite, glyphosate on soils rich in aluminum and iron oxides, phosphate on Fe(III) polyhydroxy cations modified montmorillonite, and paraquat on soil and vermiculite. While fitting the simulated data indicates an unequivocal and correct kinetic model, fitting the experimental data is not straightforward, suggesting mixed models rule the adsorption and that a large number of data points, especially at the initial steps of adsorption, provided by high throughput analysis, help to improve the kinetic modeling.
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Compostos Férricos , Poluentes Químicos da Água , Cinética , Adsorção , Solo , Análise de RegressãoRESUMO
This paper proposes the recycling of poly (methyl methacrylate) plates, formerly used in LCD monitors to produce polymer optical fibers without cladding for sensor systems and a discussion about the fabrication process of the fiber cladding is briefly presented. After disassembling LCD monitors the acrylic plate is cleaned and submitted to an extrusion process. Extrusion temperatures of 220°C, 230°C and 240°C were applied, and the produced polymer fibers were characterized by infrared and visible spectrometry, as well as evaluated for thermal analysis through differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Furthermore, a refractive index sensor was developed with the recycled fibers. Results show that the recycled fiber refractive index sensor is linear (R2 = 0.99) and presents a sensitivity of more than 4 times higher when compared to a sensor using a commercial POF.
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Objectives: Chagas disease (CD) is an infectious disease that predominantly affects poor and vulnerable populations. The last estimate conducted by the World Health Organization in Latin America regarding the prevalence of CD occurred more than 10 years ago. However, there is a scarcity of data assessing the magnitude of CD in populations residing in considered high-risk regions. Therefore, this study aimed to assess the seroprevalence of CD in an endemic region in Northern Minas Gerais through serologic screening. Methods: This is a prevalence study conducted in the municipalities of Catuti, Mato Verde, Mirabela, Montes Azul, and São Francisco, Minas Gerais, Brazil. Data collection occurred between December 2021 and December 2022, involving a questionnaire with closed-ended questions. The variables analyzed included serologic test results, stratified age groups, health indicators, and housing conditions. Results: Of the 2978 participants, 272 individuals (9.1%) tested positive for CD serology. In the age group of 4 to 14 years, 15 to 49 years, and 50 years or older, the prevalence of positive serology was 0.8% (95% confidence interval [CI] 0.16-1.43), 5.5% (95% CI 4.20-6.83), and 18.8% (95% CI 16.48-21.11), respectively. Among the participating municipalities, Mato Verde had the highest prevalence of positive serology for CD (17%). For participants aged 4 to 14 years with positive serology for CD, first-degree relatives were invited to undergo serologic testing. It was possible to collect samples from relatives of all participants in this age group. However, none of the relatives tested positive. Conclusion: This study identified a 9.1% prevalence of individuals affected by CD who were unaware of their condition. In addition, having infected children in the 4 to 14 age group with mothers with negative serology would rule out congenital transmission of the disease.
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BACKGROUND: Chagas Disease (CD) can cause Chagas cardiomyopathy. The new coronavirus disease (COVID-19) also affects the cardiovascular system and may worsen Chagas cardiomyopathy. However, the cardiac evolution of patients with CD infected by COVID-19 is not known. Thus, the objective of this study is to assess, within one year, whether there was cardiac progression after COVID-19 in CD. METHODS: Longitudinal study with CD patients. The outcome was cardiac progression, defined as the appearance of new major changes in the current ECG compared to the previous ECG considered from the comparison of electrocardiograms (ECGs) performed with an interval of one year. Positive Anti-SARS-CoV2 Serology was the independent variable of interest. For each analysis, a final multiple model was constructed, adjusted for sociodemographic, clinical, and pandemic-related characteristics. RESULTS: Of the 404 individuals included, 22.8 % had positive serology for COVID-19 and 10.9 % had cardiac progression. In the final model, positive serology for COVID-19 was the only factor associated with cardiac progression in the group as a whole (OR = 2.65; 95 % CI = 1.27-5.53) and for new-onset cardiomyopathy in the group with normal previous ECG (OR = 3.50; 95 % CI = 1.21-10.13). CONCLUSION: Our study shows an association between COVID-19 and progression of Chagas cardiomyopathy, evaluated by repeated ECGs, suggesting that COVID-19 accelerated the natural history of CD.
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Chagas disease (CD) is recognized by the World Health Organization as one of the thirteen most neglected tropical diseases in the world. Self-perceived health is considered a better predictor of mortality than objective measures of health status, and the context in which one lives influences this predictor. This study aimed to evaluate the prevalence and individual and contextual factors associated with poor self-rated health among CD patients from an endemic region in Brazil. It is a multilevel cross-sectional study. The individual data come from a cross-section of a cohort study named SaMi-Trop. Contextual data was collected from publicly accessible institutional information systems and platforms. The dependent variable was self-perceived health. The analysis was performed using multilevel binary logistic regression. The study included 1,513 patients with CD, where 335 (22.1%) had Poor self-rated health. This study revealed the influence of the organization/offer of the Brazilian public health service and of individual characteristics on the self-perceived health of patients with CD.
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Doença de Chagas , Nível de Saúde , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Estudos de Coortes , Estudos Transversais , Humanos , Análise Multinível , Fatores SocioeconômicosRESUMO
BACKGROUND: Chronic Chagas Cardiomyopathy (CCC) usually develops between 10 and 20 years after the first parasitic infection and is one of the leading causes of end-stage heart failure in Latin America. Despite the great inter-individual variability in CCC susceptibility (only 30% of infected individuals ever present CCC), there are no known predictors for disease development in those chronically infected. METHODOLOGY/PRINCIPAL FINDINGS: We describe a new susceptibility locus for CCC through a GWAS analysis in the SaMi-Trop cohort, a population-based study conducted in a Chagas endemic region from Brazil. This locus was also associated with CCC in the REDS II Study. The newly identified locus (rs34238187, OR 0.73, p-value 2.03 x 10-9) spans a haplotype of approximately 30Kb on chromosome 18 (chr18: 5028302-5057621) and is also associated with 80 different traits, most of them blood protein traits significantly enriched for immune-related biological pathways. Hi-C data show that the newly associated locus is able to interact with chromatin sites as far as 10Mb on chromosome 18 in a number of different cell types and tissues. Finally, we were able to confirm, at the tissue transcriptional level, the immune-associated blood protein signature using a multi-tissue differential gene expression and enrichment analysis. CONCLUSIONS/SIGNIFICANCE: We suggest that the newly identified locus impacts CCC risk among T cruzi infected individuals through the modulation of a downstream transcriptional and protein signature associated with host-parasite immune response. Functional characterization of the novel risk locus is warranted.
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Cardiomiopatia Chagásica , Doença de Chagas , Trypanosoma cruzi , Cromatina , Cromossomos Humanos Par 18/genética , Cromossomos Humanos Par 18/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Trypanosoma cruzi/fisiologiaRESUMO
Since phosphate is strongly related to eutrophication of environmental waters, several research groups quest for materials that can efficiently remove phosphate from wastewaters before it contaminates lakes and reservoirs. In the present work, a commercial clay mineral (K10 montmorillonite) modified with Fe3+ polyhydroxy cations was investigated as an adsorbent for phosphate. The incorporation of the polycations did not alter the main conformational characteristics of the montmorillonite, as verified by specific surface area measurements, X-ray diffractometry, FTIR, electron microscopy, and zeta potential titrations. On the other hand, the materials supporting Fe3+ polyhydroxy cations exhibited a significant enhancement of adsorption capacity, as determined by Langmuir-Freundlich isotherms, from 39 ± 2 to 104 ± 15 µmol g-1. The different ratios of OH- to Fe3+ did not affect the adsorption capacities. The adsorption kinetics was best described by the pseudo 2nd order model, approaching the equilibrium after 120 min of contact time. A variation of pH between 4.6 and 8.5 did not affect the adsorption percentages. The adsorption capacities increased with the increase of the ionic strength, thus suggesting that the formation of inner-sphere complexes prevails over electrostatic interactions as the adsorption mechanism. The materials removed phosphate from three polluted water samples having phosphate concentrations between 0.0919 and 1.211 mg L-1. The remaining phosphate concentration was below the limit of quantification of the analytical method (0.063 mg L-1 in P, or 2.0 µmol L-1). The presence of 10 mg L-1 humic of fulvic acid did not affect the performance of the materials. In conclusion, the modification of clay minerals with Fe3+ polyhydroxy cations is useful in producing low-cost adsorbents for phosphate.
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Abstract Chagas disease (CD) is recognized by the World Health Organization as one of the thirteen most neglected tropical diseases in the world. Self-perceived health is considered a better predictor of mortality than objective measures of health status, and the context in which one lives influences this predictor. This study aimed to evaluate the prevalence and individual and contextual factors associated with poor self-rated health among CD patients from an endemic region in Brazil. It is a multilevel cross-sectional study. The individual data come from a cross-section of a cohort study named SaMi-Trop. Contextual data was collected from publicly accessible institutional information systems and platforms. The dependent variable was self-perceived health. The analysis was performed using multilevel binary logistic regression. The study included 1,513 patients with CD, where 335 (22.1%) had Poor self-rated health. This study revealed the influence of the organization/offer of the Brazilian public health service and of individual characteristics on the self-perceived health of patients with CD.
Resumo A Doença de Chagas (DC) é reconhecida pela Organização Mundial da Saúde como uma das treze doenças tropicais mais negligenciadas do mundo. A autopercepção de saúde é considerada um melhor preditor de mortalidade do que medidas objetivas do estado de saúde, e o contexto em que se vive influencia esse preditor. O objetivo deste estudo foi avaliar a prevalência e os fatores individuais e contextuais associados à pior autopercepção em saúde de pacientes com DC de uma região endêmica do Brasil. É um estudo transversal multinível. Os dados individuais vêm de um corte transversal de um estudo de coorte denominado SaMi-Trop. Os dados contextuais foram coletados a partir de plataformas e sistemas de informações institucionais acessíveis ao público. A variável dependente foi a autopercepção de saúde. A análise foi realizada por meio de regressão logística binária multinível. Participaram do estudo 1.513 pacientes com DC, sendo 335 (22,1%) com pior autopercepção de saúde. Este estudo revelou a influência da organização/oferta do serviço público de saúde brasileiro e de características individuais na autopercepção de saúde de pacientes com DC.
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Sulindac is a non-steroidal antiinflammatory drug (NSAID) known to inhibit cyclooxygenases (COX) 1 and 2, and at present of interest for cancer prevention. However, its therapeutic use has been limited by its toxicity to the gastrointestinal tract and liver. We address the effects of sulindac, of the pharmacologically inactive metabolite, sulindac sulfone, and of the pharmacologically active metabolite, sudindac sulfide, on isolated rat liver mitochondria and HepG2 cells. Sulindac sulfide, but not sulindac sulfone or sulindac itself, caused mitochondrial uncoupling, released preaccumulated Ca2+ from the organelle, and decreased Hep-G2 cell viability in apparent association with cell ATP depletion resulting from mitochondrial uncoupling-associated membrane potential dissipation.
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Mitocôndrias/efeitos dos fármacos , Sulindaco/análogos & derivados , Sulindaco/farmacologia , Animais , Mitocôndrias/metabolismo , Sulindaco/química , Sulindaco/metabolismo , Células Tumorais Cultivadas , Desacopladores/farmacologiaRESUMO
Cadmium is a very important environmental toxicant, the cytotoxicity mechanism of which is likely to involve mitochondria as a target. In the present study we addressed the cause/effect relationship between the multiple cadmium-induced responses involving the mitochondrial energetic and oxidative status. Assays were performed with succinate-energized rat liver mitochondria incubated with 5 microM CdCl(2) for 0-25 min, in the absence or presence, respectively, of N-ethylmaleimide (NEM), butylhydroxytoluene (BHT), ruthenium red (RR), and cyclosporine A+ADP. A sequence of events accounting for cadmium-induced mitochondrial impairment is proposed, beginning with an apparent interaction of Cd(2+) with specific protein thiols in the mitochondrial membrane, which stimulates the cation's uptake via the Ca(2+) uniporter, and is followed by the onset of mitochondrial permeability transition (MPT); both effects dissipate the transmembrane electrical potential (Deltapsi), causing uncoupling, followed by an early depression of mitochondrial ATP levels. The respiratory chain subsequently undergoes inhibition, generating reactive oxygen species which together with iron mobilized by the cation, cause late, gradual mitochondrial membrane lipid peroxidation.
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Cádmio/farmacologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Citocromos c/análise , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Dilatação Mitocondrial/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar , Fatores de TempoRESUMO
Objetivos: descrever a evolução clínica de úlcera por pressão em dois idosos, após manejo da ferida pelo enfermeiro e evidenciar a importância da habilidade técnica no processo cicatricial de feridas. Método: estudo descritivo, do tipo caso clínico, desenvolvido no domicilio de dois pacientes idosos do município de João Pessoa/PB, Nordeste do Brasil. Este estudo teve aprovado o projeto de pesquisa pelo Comitê de Ética em Pesquisa, protocolo n.º 124/11. Resultados: paciente 1 - V.P.L, 67 anos sexo masculino, com lesão totalmente coberta por tecido necrótico infectado e paciente 2 - M.S.B, 97 anos, sexo feminino, totalmente dependente, apresentando úlcera por pressão na região sacra, infectada, odor pútrido, alto exsudato, área perilesional com sinais de inflamação. Conclusão: demonstrou-se a importância da assistência de enfermagem sistematizada para o cuidado de feridas no ambiente domiciliar.(AU)
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Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Enfermagem Domiciliar , Úlcera por Pressão/enfermagem , EpidemiologiaRESUMO
The healthy development of potato tubers requires, among other agricultural practices, proper fertilization. Potato crops require large amounts of nutrients, and therefore consume a large amount of fertilizer. In Brazilian soils, phosphorus is the nutrient that produces the highest response in tuber yields. The objective of this work was to study the effect of different levels of phosphorus fertilizer on the potato cultivar Ágata, by evaluating foliar levels of phosphorus and tuber yield under field conditions. The experiment was conducted at the Experimental Station of the Agriculture Cooperative Alto Paranaíba (COOPADAP) in Rio Paranaiba, Minas Gerais, during the 2008/2009 growing season. Treatments consisted of five doses of phosphorus (P2O5) (0, 200, 400, 600, and 800 kg ha-1), with superphosphate as the source. The phosphorus content in the leaves of potato plants decreased with increasing doses of phosphorus in the soil. The crop showed an increase in tuber productivity with increasing doses of phosphorus, reaching a maximum estimated productivity of 49.11 t ha-1 with the application of approximately 700 kg ha-1 P2O5.(AU)
O bom desenvolvimento dos tubérculos de batata requer, entre outras práticas culturais, uma adubação adequada. A cultura da batata é altamente exigente em nutrientes, sendo responsável por um elevado consumo de fertilizantes. O fósforo é o nutriente que oferece maior resposta em produtividade de tubérculos nos solos brasileiros. O objetivo deste trabalho foi estudar o efeito de doses de adubação fosfatada na cultura da batata, cultivar Ágata, avaliando-se o teor foliar e a produtividade de tubérculos, em condições de campo. O experimento foi conduzido na Estação Experimental da Cooperativa Agropecuária do Alto Paranaíba COOPADAP, localizada no município de Rio Paranaíba MG, durante o ano agrícola de 2008/2009. Os tratamentos consistiram de cinco doses de fósforo (P2O5) 0, 200, 400, 600 e 800 kg ha-1, tendo o superfosfato simples como fonte. O teor de fósforo foliar nas plantas de batata diminui com o aumento das doses de adubação fosfatada. A cultura apresenta incremento de produtividade com a adição de doses crescentes de fósforo, atingido a produtividade máxima total estimada de 49,11 t ha-1 com a aplicação de aproximadamente 700 kg ha-1 de P2O5.(AU)
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Solo/análise , Fósforo na Dieta , Esterco/análise , Tubérculos/classificação , Solanum tuberosum/classificaçãoRESUMO
The healthy development of potato tubers requires, among other agricultural practices, proper fertilization. Potato crops require large amounts of nutrients, and therefore consume a large amount of fertilizer. In Brazilian soils, phosphorus is the nutrient that produces the highest response in tuber yields. The objective of this work was to study the effect of different levels of phosphorus fertilizer on the potato cultivar Ágata, by evaluating foliar levels of phosphorus and tuber yield under field conditions. The experiment was conducted at the Experimental Station of the Agriculture Cooperative Alto Paranaíba (COOPADAP) in Rio Paranaiba, Minas Gerais, during the 2008/2009 growing season. Treatments consisted of five doses of phosphorus (P2O5) (0, 200, 400, 600, and 800 kg ha-1), with superphosphate as the source. The phosphorus content in the leaves of potato plants decreased with increasing doses of phosphorus in the soil. The crop showed an increase in tuber productivity with increasing doses of phosphorus, reaching a maximum estimated productivity of 49.11 t ha-1 with the application of approximately 700 kg ha-1 P2O5.
O bom desenvolvimento dos tubérculos de batata requer, entre outras práticas culturais, uma adubação adequada. A cultura da batata é altamente exigente em nutrientes, sendo responsável por um elevado consumo de fertilizantes. O fósforo é o nutriente que oferece maior resposta em produtividade de tubérculos nos solos brasileiros. O objetivo deste trabalho foi estudar o efeito de doses de adubação fosfatada na cultura da batata, cultivar Ágata, avaliando-se o teor foliar e a produtividade de tubérculos, em condições de campo. O experimento foi conduzido na Estação Experimental da Cooperativa Agropecuária do Alto Paranaíba COOPADAP, localizada no município de Rio Paranaíba MG, durante o ano agrícola de 2008/2009. Os tratamentos consistiram de cinco doses de fósforo (P2O5) 0, 200, 400, 600 e 800 kg ha-1, tendo o superfosfato simples como fonte. O teor de fósforo foliar nas plantas de batata diminui com o aumento das doses de adubação fosfatada. A cultura apresenta incremento de produtividade com a adição de doses crescentes de fósforo, atingido a produtividade máxima total estimada de 49,11 t ha-1 com a aplicação de aproximadamente 700 kg ha-1 de P2O5.