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1.
Clin Infect Dis ; 78(6): 1669-1676, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38324908

ABSTRACT

BACKGROUND: An active search for tuberculosis cases through mass screening is widely described as a tool to improve case detection in hyperendemic settings. However, its effectiveness in high-risk populations, such as incarcerated people, is debated. METHODS: Between 2017 and 2021, 3 rounds of mass screening were carried out in 3 Brazilian prisons. Social and health questionnaires, chest X-rays, and Xpert MTB/RIF were performed. RESULTS: More than 80% of the prison population was screened. Overall, 684 cases of pulmonary tuberculosis were diagnosed. Prevalence across screening rounds was not statistically different. Among incarcerated persons with symptoms, the overall prevalence of tuberculosis per 100 000 persons was 8497 (95% confidence interval [CI], 7346-9811), 11 115 (95% CI, 9471-13 082), and 7957 (95% CI, 6380-9882) in screening rounds 1, 2, and 3, respectively. Similar to our overall results, there were no statistical differences between screening rounds and within individual prisons. We found no statistical differences in Computer-Aided Detection for TB version 5 scores across screening rounds among people with tuberculosis-the median scores in rounds 1, 2, and 3 were 82 (interquartile range [IQR], 63-97), 77 (IQR, 60-94), and 81 (IQR, 67-92), respectively. CONCLUSIONS: In this environment with hyperendemic rates of tuberculosis, 3 rounds of mass screening did not reduce the overall tuberculosis burden. In prisons, where a substantial number of tuberculosis cases is undiagnosed annually, a range of complementary interventions and more frequent tuberculosis cases screening may be required.


Subject(s)
Mass Screening , Prisoners , Prisons , Tuberculosis, Pulmonary , Humans , Brazil/epidemiology , Prisoners/statistics & numerical data , Mass Screening/methods , Male , Adult , Female , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/epidemiology , Prevalence , Middle Aged , Prisons/statistics & numerical data , Young Adult , Mycobacterium tuberculosis/isolation & purification , Tuberculosis/diagnosis , Tuberculosis/epidemiology
2.
Int J Mol Sci ; 24(13)2023 Jun 27.
Article in English | MEDLINE | ID: mdl-37445883

ABSTRACT

To effectively use (Li) lithium metal anodes, it is becoming increasingly necessary to create membranes with high lithium conductivity, electrochemical and thermal stabilities, as well as adequate mechanical properties. Composite gel polymer electrolytes (CGPE) have emerged as a promising strategy, offering improved ionic conductivity and structural performance compared to polymer electrolytes. In this study, a simple and scalable approach was developed to fabricate a crosslinked polyethylene oxide (PEO)-based membrane, comprising two different glass fiber reinforcements, in terms of morphology and thickness. The incorporation of a solvated ionic liquid into the developed membrane enhances the ionic conductivity and reduces flammability in the resulting CGPE. Galvanostatic cycling experiments demonstrate favorable performance of the composite membrane in symmetric Li cells. Furthermore, the CGPE demonstrated electrochemical stability, enabling the cell to cycle continuously for more than 700 h at a temperature of 40 °C without short circuits. When applied in a half-cell configuration with lithium iron phosphate (LFP) cathodes, the composite membrane enabled cycling at different current densities, achieving a discharge capacity of 144 mAh·g-1. Overall, the findings obtained in this work highlight the potential of crosslinked PEO-based composite membranes for high-performance Li metal anodes, with enhanced near room temperature conductivity, electrochemical stability, and cycling capability.


Subject(s)
Electrolytes , Lithium , Amines , Epoxy Resins , Polymers
3.
Article in English | MEDLINE | ID: mdl-35647574

ABSTRACT

Background: Globally, prisons are high-incidence settings for tuberculosis. Yet the role of prisons as reservoirs of M. tuberculosis, propagating epidemics through spillover to surrounding communities, has been difficult to measure directly. Methods: To quantify the role of prisons in driving wider community M. tuberculosis transmission, we conducted prospective genomic surveillance in Central West Brazil from 2014 to 2019. We whole genome sequenced 1152 M. tuberculosis isolates collected during active and passive surveillance inside and outside prisons and linked genomes to detailed incarceration histories. We applied multiple phylogenetic and genomic clustering approaches and inferred timed transmission trees. Findings: M. tuberculosis sequences from incarcerated and non-incarcerated people were closely related in a maximum likelihood phylogeny. The majority (70.8%; 46/65) of genomic clusters including people with no incarceration history also included individuals with a recent history of incarceration. Among cases in individuals with no incarceration history, 50.6% (162/320) were in clusters that included individuals with recent incarceration history, suggesting that transmission chains often span prisons and communities. We identified a minimum of 18 highly probable spillover events, M. tuberculosis transmission from people with a recent incarceration history to people with no prior history of incarceration, occurring in the state's four largest cities and across sampling years. We additionally found that frequent transfers of people between the state's prisons creates a highly connected prison network that likely disseminates M. tuberculosis across the state. Interpretation: We developed a framework for measuring spillover from high-incidence environments to surrounding communities by integrating genomic and spatial information. Our findings indicate that, in this setting, prisons serve not only as disease reservoirs, but also disseminate M. tuberculosis across highly connected prison networks, both amplifying and propagating M. tuberculosis risk in surrounding communities. Funding: Brazil's National Council for Scientific and Technological Development and US National Institutes of Health.

4.
Mycoses ; 65(7): 715-723, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35524507

ABSTRACT

BACKGROUND: Data on the prevalence of chronic pulmonary aspergillosis (CPA) in patients with active or cured tuberculosis (TB) are scarce, mainly due to diagnostic difficulties. The diagnosis of CPA is based on pulmonary symptoms and chest computed tomography (CT) scans and is considered confirmed when there is microbiological or serological evidence of Aspergillus spp. OBJECTIVES: To estimate the prevalence of CPA in patients treated or undergoing treatment for PTB, seen in two referral hospitals in Mato Grosso do Sul, Brazil. PATIENTS AND METHODS: A total of 193 consecutive patients who were treated or previously treated for pulmonary tuberculosis underwent prospective evaluation: (a) clinical evaluation; (b) chest CT scan; (c) sputum examination-culture for fungi and smears for direct mycology; (d) detection of anti-Aspergillus fumigatus antibodies using an enzyme-linked immunosorbent assay Platelia® test; and (e) anti-Aspergillus spp. antibodies were assessed via a DID test. RESULTS: The global prevalence of CPA was 10.9% (95% confidence interval, 7.2%-16.1%), but it increased with the time of TB diagnosis. The variables independently associated with CPA were previous pulmonary tuberculosis over 4 years ago and haemoptysis. Cavities, pleural thickening and the presence of a fungal ball were the most frequent tomographic findings in patients with CPA. CONCLUSIONS: The high prevalence observed and its increase over time suggest the need for continuous surveillance of CPA in patients with active or previous pulmonary tuberculosis and throughout life, with clinical, tomographic and serological evaluations (ELISA) for a timely diagnosis and a better prognosis.


Subject(s)
Pulmonary Aspergillosis , Tuberculosis, Pulmonary , Tuberculosis , Aspergillus , Brazil/epidemiology , Chronic Disease , Humans , Persistent Infection , Prevalence , Prospective Studies , Pulmonary Aspergillosis/complications , Pulmonary Aspergillosis/diagnosis , Pulmonary Aspergillosis/epidemiology , Tuberculosis/complications , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/epidemiology
5.
Polymers (Basel) ; 14(3)2022 Jan 20.
Article in English | MEDLINE | ID: mdl-35160393

ABSTRACT

Solid-state electrolytes are a promising family of materials for the next generation of high-energy rechargeable lithium batteries. Polymer electrolytes (PEs) have been widely investigated due to their main advantages, which include easy processability, high safety, good mechanical flexibility, and low weight. This review presents recent scientific advances in the design of versatile polymer-based electrolytes and composite electrolytes, underlining the current limitations and remaining challenges while highlighting their technical accomplishments. The recent advances in PEs as a promising application in structural batteries are also emphasized.

6.
Emerg Infect Dis ; 27(3): 905-914, 2021 03.
Article in English | MEDLINE | ID: mdl-33622493

ABSTRACT

International migrants are at heightened risk for tuberculosis (TB) disease. Intensified incarceration at international borders may compound population-wide TB risk. However, few studies have investigated the contributions of migration, local transmission, or prisons in driving incident TB at international borders. We conducted prospective population-based genomic surveillance in 3 cities along Brazil's central western border from 2014-2017. Although most isolates (89/132; 67%) fell within genomic transmission clusters, genetically unique isolates disproportionately occurred among participants with recent international travel (17/42; 40.5%), suggesting that both local transmission and migration contribute to incident TB. Isolates from 40 participants with and 76 without an incarceration history clustered together throughout a maximum-likelihood phylogeny, indicating the close interrelatedness of prison and community epidemics. Our findings highlight the need for ongoing surveillance to control continued introductions of TB and reduce the disproportionate burden of TB in prisons at Brazil's international borders.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Brazil , Humans , Prisons , Prospective Studies , Travel
7.
J Biomed Mater Res B Appl Biomater ; 109(7): 961-972, 2021 07.
Article in English | MEDLINE | ID: mdl-33241654

ABSTRACT

In this study, composite scaffolds based on poly(caprolactone) (PCL) and non-covalently functionalized few-layer graphene (FLG) were manufactured by an extrusion-based system for the first time. For that, functionalized FLG powder was obtained through the evaporation of a functionalized FLG aqueous suspension prepared from a graphite precursor. Cryomilling was shown to be an efficient mixing method, producing a homogeneous dispersion of FLG particles onto the PCL polymeric matrix. Thereafter, fused deposition modeling (FDM) was used to print 3D scaffolds and their morphology, thermal, biodegradability, mechanical, and cytotoxicity properties were analysed. The presence of functionalized FLG demonstrated to induce slight changes in the microstructure of the scaffold, did not affect the thermal stability and enhanced significantly the compressive modulus. The composite scaffolds presented a porosity of around 40% and a mean pore size in the range of 300 µm. The cell viability and proliferation of SaOs-2 cells were assessed and the results showed good cell viability and long-term proliferation onto produced composite scaffolds. Therefore, these new FLG/PCL scaffolds comprised adequate morphological, thermal, mechanical, and biological properties to be used in bone tissue regeneration.


Subject(s)
Bone Regeneration/drug effects , Bone Substitutes , Graphite , Materials Testing , Polyesters , Printing, Three-Dimensional , Bone Substitutes/chemistry , Bone Substitutes/pharmacology , Cell Line, Tumor , Graphite/chemistry , Graphite/pharmacology , Humans , Polyesters/chemistry , Polyesters/pharmacology
8.
Nanomaterials (Basel) ; 9(10)2019 Oct 04.
Article in English | MEDLINE | ID: mdl-31590276

ABSTRACT

Single walled carbon nanotubes (SWCNT) were functionalized using the 1,3-dipolar cycloaddition reaction of an azomethine ylide under solvent-free conditions, a one-pot procedure that yields pyrrolidine type of groups at the nanotubes surface. The functionalized SWCNT were further decorated with Ag and Cu nanoparticles by reduction of the corresponding metal salts in dimethylformamide. The extensive reduction of silver from its nitrate was observed, as well as the partial reduction of copper from its acetate. X-ray photoelectron spectroscopy (XPS) confirmed the functionalization of SWCNT with pyrrolidine that provided anchoring sites for the metal nanoparticles. Metal nanoparticles (NP) were formed at the surface of the organically functionalized SWCNT in higher yields as compared to the same procedure carried out with pristine SWCNT. This was observed using scanning electron microscopy (SEM) and quantified by XPS. Raman spectroscopy demonstrated that functionalization and metal decoration of the SWCNT did not induce structural damage to the SWCNT.

9.
Am J Trop Med Hyg ; 101(4): 774-779, 2019 10.
Article in English | MEDLINE | ID: mdl-31392954

ABSTRACT

National border areas are special places for the spread of Mycobacterium tuberculosis (MTB). These regions concentrate vulnerable populations and constant population movements. Understanding the dynamics of the transmission of MTB is fundamental to propose control measures and to monitor drug resistance. We conducted a population-based prospective study of tuberculosis (TB) to evaluate molecular characteristics of MTB isolates circulating in Roraima, a state on the border of Venezuela and Guyana. Eighty isolates were genotyped by IS6110-RFLP (restriction fragment length polymorphism), spoligotyping, and 24-locus mycobacterial interspersed repetitive unit-variable number of repeats tandem (MIRU-VNTR). Drug susceptibility tests were performed by using the proportion method and GeneXpert® MTB/RIF (Cepheid, Sunnyvale, CA). Isolates showing a phenotypic resistance profile were submitted to polymerase chain reaction (PCR) and sequencing. Spoligotyping showed 40 distinct patterns with a high prevalence of Latin-American and Mediterranean (LAM), Haarlem (H), and the "ill-defined" T clades. Mycobacterial interspersed repetitive unit -VNTR and IS6110-RFLP showed clustering rates of 21.3% and 30%, respectively. Drug resistance was detected in 11 (15.1%) isolates, and all were found to have primary resistance; among these, six (8.2%) isolates were streptomycin mono-resistant, four (5.4%) isoniazid mono-resistant, and one (1.3%) multidrug resistant. This is the first study on the molecular epidemiology and drug resistance profile of MTB from Roraima. Herein, we describe high diversity of genetic profiles circulating in this region that may be driven by the introduction of new strain types because of large population flow in this region. In summary, our results showed that analyses of these circulating strains can contribute to a better understanding of TB epidemiology in the northern Brazilian border and be useful to establish public health policies on TB prevention.


Subject(s)
Genetic Variation , Mycobacterium tuberculosis/genetics , Tuberculosis/epidemiology , Adolescent , Adult , Brazil/epidemiology , Cluster Analysis , Drug Resistance, Bacterial , Female , Genotype , Humans , Male , Middle Aged , Minisatellite Repeats/genetics , Molecular Epidemiology , Mycobacterium tuberculosis/isolation & purification , Polymorphism, Restriction Fragment Length , Prospective Studies , Tuberculosis/microbiology , Young Adult
10.
J Bras Pneumol ; 45(2): e20180185, 2019 Apr 18.
Article in English, Portuguese | MEDLINE | ID: mdl-31017227

ABSTRACT

OBJECTIVE: To evaluate the accuracy of rapid molecular testing as a diagnostic tool and estimate the incidence of smear-positive pulmonary tuberculosis among the indigenous population. METHODS: This is an epidemiological study based on secondary data. We calculated the incidence of smear-positive pulmonary tuberculosis between January 1st, 2011 and December 31, 2016, and the performance of bacilloscopy and rapid molecular testing in diagnosing pulmonary tuberculosis compared to sputum culture (standard test). RESULTS: We included 4,048 cases of indigenous people with respiratory symptoms who provided sputum samples for analysis. Among them, 3.7%, 6.7%, and 3.7% had positive results for bacilloscopy, sputum culture, and rapid molecular testing, respectively. The mean incidence of pulmonary tuberculosis was 269.3/100 thousand inhabitants. Rapid molecular testing had 93.1% sensitivity and 98.2% specificity, compared to sputum culture. Bacilloscopy showed 55.1% sensitivity and 99.6% specificity. CONCLUSIONS: Rapid molecular testing can be useful in remote areas with limited resources and a high incidence of tuberculosis, such as indigenous villages in rural regions of Brazil. In addition, the main advantages of rapid molecular testing are its easy handling, fast results, and the possibility of detecting rifampicin resistance. Together, these attributes enable the early start of treatment, contributing to reduce the transmission in communities recognized as vulnerable to infection and disease.


Subject(s)
Indians, South American/statistics & numerical data , Molecular Diagnostic Techniques/methods , Mycobacterium leprae/isolation & purification , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/ethnology , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Brazil/epidemiology , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Incidence , Infant , Male , Middle Aged , Reference Values , Reproducibility of Results , Sensitivity and Specificity , Sex Distribution , Sputum/microbiology , Time Factors , Tuberculosis, Pulmonary/microbiology , Young Adult
11.
Nanoscale Adv ; 1(4): 1432-1441, 2019 Apr 09.
Article in English | MEDLINE | ID: mdl-36132604

ABSTRACT

In this work, the functionalization of graphene nanoplatelets (GNPs) performed by a solvent-free cycloaddition reaction on GNPs with iminodiacetic acid (IDA) and paraformaldehyde (PFA), and the functionality analysis of the resulting functionalized GNPs (f-GNPs) by Boehm titration are introduced. The f-GNPs synthesized at different temperatures were characterized by X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM) for structural and morphological properties. Back titration of the f-GNPs selectively identified 3 types of functional groups on the f-GNP surface, carboxylic, lactonic and phenolic, and suggested that 200 °C gives the highest carboxylic group functionality. With the reaction temperature increasing from 180 to 220 °C, a decrease in the phenolic functionality and an increase in that of lactonic are observed. In the case of 250 °C reactions, it was found that the carboxylic functionality is greatly reduced, while the phenolic functionality showed a significant increase. The f-GNP samples were further characterized by thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS), the results of which showed a good agreement with the titration analysis.

12.
J. bras. pneumol ; 45(2): e20180185, 2019. tab
Article in English | LILACS | ID: biblio-1002431

ABSTRACT

ABSTRACT Objective: To evaluate the accuracy of rapid molecular testing as a diagnostic tool and estimate the incidence of smear-positive pulmonary tuberculosis among the indigenous population. Methods: This is an epidemiological study based on secondary data. We calculated the incidence of smear-positive pulmonary tuberculosis between January 1st, 2011 and December 31, 2016, and the performance of bacilloscopy and rapid molecular testing in diagnosing pulmonary tuberculosis compared to sputum culture (standard test). Results: We included 4,048 cases of indigenous people with respiratory symptoms who provided sputum samples for analysis. Among them, 3.7%, 6.7%, and 3.7% had positive results for bacilloscopy, sputum culture, and rapid molecular testing, respectively. The mean incidence of pulmonary tuberculosis was 269.3/100 thousand inhabitants. Rapid molecular testing had 93.1% sensitivity and 98.2% specificity, compared to sputum culture. Bacilloscopy showed 55.1% sensitivity and 99.6% specificity. Conclusions: Rapid molecular testing can be useful in remote areas with limited resources and a high incidence of tuberculosis, such as indigenous villages in rural regions of Brazil. In addition, the main advantages of rapid molecular testing are its easy handling, fast results, and the possibility of detecting rifampicin resistance. Together, these attributes enable the early start of treatment, contributing to reduce the transmission in communities recognized as vulnerable to infection and disease.


RESUMO Objetivo: Avaliar a acurácia do teste rápido molecular como ferramenta diagnóstica e estimar a incidência de casos pulmonares positivos entre a população indígena. Métodos: Estudo epidemiológico baseado em dados secundários. Foi calculada a incidência de casos de tuberculose pulmonar positiva entre 1° de janeiro de 2011 e 31 de dezembro de 2016, e o desempenho da baciloscopia e do teste rápido molecular no diagnóstico de tuberculose pulmonar, em comparação à cultura de escarro (teste padrão). Resultados: Foram incluídos 4.048 casos de indígenas considerados sintomáticos respiratórios, que forneceram amostras de escarro para análise. Destes, 3,7%, 6,7% e 3,7% apresentaram resultados positivos para baciloscopia, cultura e teste rápido molecular, respectivamente. A incidência média de tuberculose pulmonar foi de 269,3/100 mil habitantes. A sensibilidade do teste rápido molecular, em relação à cultura, foi 93,1% e a especificidade foi 98,2%. A baciloscopia apresentou sensibilidade 55,1% e especificidade 99,6%. Conclusões: O teste rápido molecular pode ser útil em áreas remotas, com recursos limitados e incidência de tuberculose elevada, como as aldeias indígenas nas áreas rurais do país. Ademais, o teste rápido molecular apresenta como principais vantagens o fácil manuseio, os resultados rápidos e a possibilidade de identificar a resistência à rifampicina. Em conjunto, esses atributos facilitam o início do tratamento precoce, contribuindo para reduzir a transmissão em comunidades reconhecidamente vulneráveis à infecção e à doença.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/ethnology , Indians, South American/statistics & numerical data , Molecular Diagnostic Techniques/methods , Mycobacterium leprae/isolation & purification , Reference Values , Sputum/microbiology , Time Factors , Tuberculosis, Pulmonary/microbiology , Brazil/epidemiology , Incidence , Cross-Sectional Studies , Reproducibility of Results , Sensitivity and Specificity , Sex Distribution , Age Distribution
13.
Article in Portuguese | SES-MS, Coleciona SUS, CONASS | ID: biblio-1141390

ABSTRACT

A tuberculose continua sendo grave problema mundial de saúde pública. Seu diagnóstico precoce e tratamento ainda constituem desafios. Entre os recursos diagnósticos, a cultura de Mycobacterium tuberculosis é padrão-ouro. Objetivo: Relatar como a semeadura com a técnica Ogawa-Kudoh foi descentralizada em Mato Grosso do Sul e descrever os benefícios de diagnosticar precocemente a doença e a resistência, bem como o uso dos resultados como fonte de pesquisa. Materiais e Métodos: A técnica foi escolhida por sua simplicidade, sensibilidade e baixo custo, por não requerer centrífuga, estufa ou cabine de segurança biológica e pela facilidade de transporte dos semeados em temperatura ambiente, favorecendo o atendimento de populações distantes dos grandes centros. A descentralização da semeadura ocorreu após identificação ou adaptação de estruturas locais, capacitação de pessoal e fornecimento de insumos. Subsequente apoio técnico, supervisões e monitoramento foram proporcionados. Resultados: O uso da técnica iniciou-se em 1999 no laboratório do Hospital Porta da Esperança, em Dourados, então único serviço para tratamento de tuberculose em povos indígenas. Gradativamente, expandiu-se a outros municípios e populações. Atualmente, cerca de 60% da população sul-mato-grossense é coberta por este recurso laboratorial, destacando-se populações privadas de liberdade, fronteiriças e de áreas prioritárias para o controle da doença. Conclusão: A nova rotina contribuiu para o controle da tuberculose no estado, tanto pelo diagnóstico precoce da doença como da resistência a drogas, favorecendo também estudos e avaliações de relevância epidemiológica.


Worldwide, tuberculosis remains a serious public health problem. Its early diagnosis and treatment still constitute challenges. Mycobacterium tuberculosis culture is the gold standard among diagnostic resources. Objective: To report how culture seeding employing the Ogawa-Kudoh technique was decentralized in Mato Grosso do Sul and describe the benefits obtained from early diagnosis and detection of drug resistance. The use of the resulting data as sources for further research is also reported. Materials and Methods: The technique was selected for its simplicity, sensitivity, and low cost, for not requiring centrifuges, incubators, or biosafety cabins, and for the convenience of seeded plate transportation at room temperature, facilitating the provision of diagnostic services to populations living far from major centers. Decentralization of culture seeding was preceded by identification or adaptation of local structures and by staff training and supply of materials and equipment. Subsequent technical support, supervision, and monitoring were provided. Results: The technique was implemented in 1999 in the laboratory of the Hospital Porta da Esperança, in Dourados county, then the only service providing tuberculosis treatment to indigenous patients, and gradually expanded to other counties and populations. Today, roughly 60% of Mato Grosso do Sul residents are covered by the resource, and more crucially populations deprived of freedom and those living in border regions or areas prioritized for tuberculosis control. Conclusion: The new routine contributed to tuberculosis control in the state, improving early diagnosis and detection of drug resistance and fostering epidemiologically relevant studies and evaluations


Subject(s)
Humans , Tuberculosis , Early Diagnosis , Public Health , Low Cost Technology , Indigenous Peoples
14.
Nanomaterials (Basel) ; 8(9)2018 Aug 30.
Article in English | MEDLINE | ID: mdl-30200191

ABSTRACT

The search for graphene or few-layer graphene production methods that are simple, allow mass production, and yield good quality material continues to provoke intense investigation. The present work contributes to this investigation through the study of the aqueous exfoliation of four types of graphene sources, which are namely graphite and graphite nanoflakes with different morphologies and geographical origins. The exfoliation was achieved in an aqueous solution of a soluble pyrene derivative that was synthesized to achieve maximum interaction with the graphene surface at low concentration (5 × 10-5 M). The yield of bilayer and few-layer graphene obtained was quantified by Raman spectroscopic analysis, and the adsorption of the pyrene derivative on the graphene surface was studied by thermogravimetric analysis and X-ray diffraction. The whole procedure was rationalized with the help of molecular modeling.

15.
Rev Soc Bras Med Trop ; 51(3): 324-330, 2018.
Article in English | MEDLINE | ID: mdl-29972563

ABSTRACT

INTRODUCTION: High endemic levels of pulmonary tuberculosis in prisons result from overcrowding, limited access to healthcare, delayed diagnosis, sustained transmission owing to poor control measures, and multidrug resistance. This study evaluated locally implemented measures for early pulmonary tuberculosis diagnosis and evaluated resistance to anti-tuberculosis drugs. METHODS: This transversal study employed data from the Mato Grosso do Sul State Tuberculosis Control Program obtained from 35 correctional facilities in 16 counties for 2 periods (2007-2010 and 2011-2014). RESULTS: Statewide prevalence (per 100,000) was 480.0 in 2007 and 972.9 in 2014. The following indicators showed improvement: alcohol-acid-fast bacillus testing (from 82.7% to 92.9%); cultures performed (55.0% to 81.8%); drug susceptibility testing of positive cultures (71.6% to 62.4%); and overall drug susceptibility testing coverage (36.6% to 47.4%). Primary and acquired resistance rates for 2007-2014 were 21.1% and 30.0%, respectively. Primary and acquired multidrug resistance rates were 0.3% and 1.3%, respectively. CONCLUSIONS: Prevalence rates increased, and laboratory indicators improved as a result of capacity building and coordination of technical teams and other individuals providing healthcare to inmates. Resistance rates were high, thereby negatively affecting disease control.


Subject(s)
Antitubercular Agents/administration & dosage , Prisons/statistics & numerical data , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/drug therapy , Brazil/epidemiology , Cross-Sectional Studies , Early Diagnosis , Humans , Prevalence , Risk Factors , Tuberculosis, Multidrug-Resistant/epidemiology , Tuberculosis, Pulmonary/epidemiology
16.
Rev. Soc. Bras. Med. Trop ; 51(3): 324-330, Apr.-June 2018. tab
Article in English | LILACS | ID: biblio-957432

ABSTRACT

Abstract INTRODUCTION: High endemic levels of pulmonary tuberculosis in prisons result from overcrowding, limited access to healthcare, delayed diagnosis, sustained transmission owing to poor control measures, and multidrug resistance. This study evaluated locally implemented measures for early pulmonary tuberculosis diagnosis and evaluated resistance to anti-tuberculosis drugs. METHODS: This transversal study employed data from the Mato Grosso do Sul State Tuberculosis Control Program obtained from 35 correctional facilities in 16 counties for 2 periods (2007-2010 and 2011-2014). RESULTS: Statewide prevalence (per 100,000) was 480.0 in 2007 and 972.9 in 2014. The following indicators showed improvement: alcohol-acid-fast bacillus testing (from 82.7% to 92.9%); cultures performed (55.0% to 81.8%); drug susceptibility testing of positive cultures (71.6% to 62.4%); and overall drug susceptibility testing coverage (36.6% to 47.4%). Primary and acquired resistance rates for 2007-2014 were 21.1% and 30.0%, respectively. Primary and acquired multidrug resistance rates were 0.3% and 1.3%, respectively. CONCLUSIONS: Prevalence rates increased, and laboratory indicators improved as a result of capacity building and coordination of technical teams and other individuals providing healthcare to inmates. Resistance rates were high, thereby negatively affecting disease control.


Subject(s)
Humans , Prisons/statistics & numerical data , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/drug therapy , Tuberculosis, Multidrug-Resistant/diagnosis , Tuberculosis, Multidrug-Resistant/drug therapy , Antitubercular Agents/administration & dosage , Tuberculosis, Pulmonary/epidemiology , Brazil/epidemiology , Prevalence , Cross-Sectional Studies , Risk Factors , Tuberculosis, Multidrug-Resistant/epidemiology , Early Diagnosis
17.
Am J Trop Med Hyg ; 98(2): 372-375, 2018 02.
Article in English | MEDLINE | ID: mdl-29210353

ABSTRACT

We conducted a population-based study of tuberculosis (TB) from 2009 to 2015 in an indigenous community of Brazil, the largest in the country, to investigate risk factors associated with recent TB transmission. The clinical isolates of Mycobacterium tuberculosis were genotyped by IS6110-RFLP (restriction fragment length polymorphism) and spoligotyping analysis. Among 67 isolates typed by RFLP, 69% fell into fifteen clusters, and 91% of TB cases with shared IS6110-RFLP pattern were diagnosed within 2 years of another case in the cluster. Individual risk factors associated with genetic clustering were domestic overcrowding (odds ratio [OR]: 6.10; 95% confidence interval [CI]: 1.50-24.88) and low social class (OR: 3.72; 95% CI: 1.00-13.98). Most reported contacts (76%) were identified within the household of the index TB case, but most of the genetic clustering of M. tuberculosis occurred outside of household (79%). Expanded contacts investigation and prophylaxis outside of household should be considered as a priority for TB control programs in this population.


Subject(s)
Cluster Analysis , Population Groups/statistics & numerical data , Tuberculosis/genetics , Adult , Brazil/epidemiology , Brazil/ethnology , Contact Tracing , Family Characteristics/ethnology , Female , Humans , Male , Middle Aged , Molecular Epidemiology , Multivariate Analysis , Population Groups/ethnology , Risk Factors , Surveys and Questionnaires , Tuberculosis/epidemiology , Tuberculosis/ethnology
18.
RSC Adv ; 8(58): 33564-33573, 2018 Sep 24.
Article in English | MEDLINE | ID: mdl-35548120

ABSTRACT

Graphene nanoplatelets (GNPs) were functionalized through 1,3-dipolar cycloaddition of azomethine ylide using a solvent-free approach and under different reaction conditions. The yield and the functionality of the carboxyl-terminated pyrrolidine ring attached on the surface of GNPs could be affected by varying the reaction temperature as well as the reactant to GNP weight ratio. The functionalized GNPs were characterized extensively using a range of spectroscopic and microscopy techniques.

19.
Rev Panam Salud Publica ; 41: e9, 2017 Apr 20.
Article in Portuguese | MEDLINE | ID: mdl-28444009

ABSTRACT

OBJECTIVE: To estimate the rate of drug resistance among pulmonary tuberculosis (PTB) cases in the state of Mato Grosso do Sul, Brazil, and specifically in the border areas with Paraguay and Bolivia, as well as to identify associated risk factors. METHOD: The present cross-sectional, epidemiological study focused on PTB cases recorded between January 2007 and December 2010 in the State Reportable Disease Information System with results of susceptibility tests to rifampicin, isoniazid, ethambutol, and streptomycin. Dependent variables were development of resistance to a single drug or any combination of drugs. Independent variables were being a new or treated case, living in border areas, presence/absence of diabetes, and history of alcoholism. RESULTS: There were 789 TBP cases with susceptibility testing. The following characteristics were associated with resistance: treated case (P = 0.0001), border region (P = 0.0142), alcoholism (P = 0.0451), and diabetes (P = 0.0708). The rates of combined, primary, and acquired resistance for the state were 16.3%, 10.6%, and 39.0%, vs. 22.3%, 19.2%, and 37.5% for the border region. The rates of combined, primary, and acquired multidrug resistance for the state were 1.8%, 0.6%, and 6.3%, vs. 3.1%, 1.2%, and 12.5% for the border region. CONCLUSIONS: In the border region, the state should investigate drug resistance in all patients with respiratory symptoms, determine the pattern of resistance in confirmed cases, adopt directly observed treatment for cases of PTB, and develop health actions together with neighboring countries. Across the state, the levels of acquired resistance should be monitored, with investigation of resistance in all treated cases and implementation of directly observed treatment especially among patients with diabetes or alcoholism.


Subject(s)
Antitubercular Agents/therapeutic use , Tuberculosis, Multidrug-Resistant/drug therapy , Adolescent , Adult , Aged , Bolivia , Brazil , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Paraguay , Tuberculosis, Multidrug-Resistant/epidemiology , Young Adult
20.
Article in Portuguese | PAHO-IRIS | ID: phr-33839

ABSTRACT

Objetivo. Estimar as taxas de resistência às drogas entre casos de tuberculose pulmonar (TBP) para o estado de Mato Grosso do Sul, Brasil, e especificamente para a região da fronteira com Paraguai e Bolívia, além de identificar fatores de risco associados. Métodos. O presente estudo epidemiológico, transversal, enfocou os casos de TBP registrados de janeiro de 2007 a dezembro de 2010 no Sistema de Informação de Agravos de Notificação da Secretaria de Estado de Saúde com resultados do teste de suscetibilidade a rifampicina, isoniazida, etambutol e estreptomicina. Definiram-se como variáveis dependentes o desenvolvimento de resistência a uma única droga e a qualquer combinação de drogas. As variáveis independentes foram ser caso novo ou tratado, residência em região de fronteira ou outra região, presença ou ausência de diabetes e história de alcoolismo. Resultados. Foram identificados 789 casos de TBP com teste de suscetibilidade. As características associadas à resistência foram: caso tratado (P=0,0001), região de fronteira (P=0,0142), alcoolismo (P=0,0451) e diabetes (P=0,0708). As taxas de resistência combinada, primária e adquirida no estado foram de 16,3%, 10,6% e 39,0%, e na fronteira, de 22,3%, 19,2% e 37,5%. As taxas de resistência a múltiplas drogas combinada, primária e adquirida no estado foram de 1,8%, 0,6% e 6,3%, e na fronteira, de 3,1%, 1,2% e 12,5%. Conclusões. O estado deve, na região de fronteira, realizar cultura em todos os sintomáticos respiratórios, investigar o padrão de resistência nos casos confirmados, adotar o tratamento diretamente observado nos casos de TBP e desencadear ações de saúde conjuntas com os países fronteiriços. Em todo o estado, é necessário monitorar os níveis de resistência adquirida, ampliar a investigação de resistência para todos os casos tratados e adotar o tratamento diretamente observado prioritariamente entre pacientes com alcoolismo e diabetes.


Objective. To estimate the rate of drug resistance among pulmonary tuberculosis (PTB) cases in the state of Mato Grosso do Sul, Brazil, and specifically in the border areas with Paraguay and Bolivia, as well as to identify associated risk factors. Method. The present cross-sectional, epidemiological study focused on PTB cases recorded between January 2007 and December 2010 in the State Reportable Disease Information System with results of susceptibility tests to rifampicin, isoniazid, ethambutol, and streptomycin. Dependent variables were development of resistance to a single drug or any combination of drugs. Independent variables were being a new or treated case, living in border areas, presence/absence of diabetes, and history of alcoholism. Results. There were 789 TBP cases with susceptibility testing. The following characteristics were associated with resistance: treated case (P=0.0001), border region (P=0.0142), alcoholism (P=0.0451), and diabetes (P=0.0708). The rates of combined, primary, and acquired resistance for the state were 16.3%, 10.6%, and 39.0%, vs. 22.3%, 19.2%, and 37.5% for the border region. The rates of combined, primary, and acquired multidrug resistance for the state were 1.8%, 0.6%, and 6.3%, vs. 3.1%, 1.2%, and 12.5% for the border region. Conclusions. In the border region, the state should investigate drug resistance in all patients with respiratory symptoms, determine the pattern of resistance in confirmed cases, adopt directly observed treatment for cases of PTB, and develop health actions together with neighboring countries. Across the state, the levels of acquired resistance should be monitored, with investigation of resistance in all treated cases and implementation of directly observed treatment especially among patients with diabetes or alcoholism.


Subject(s)
Tuberculosis, Pulmonary , Drug Resistance , Border Areas , Diabetes Mellitus , Alcoholism , Paraguay , Bolivia , Drug Resistance , Border Areas , Brazil
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