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1.
Environ Geochem Health ; 46(6): 190, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695943

RESUMO

A magnetic nanocomposite of hydroxyapatite and biomass (HAp-CM) was synthesized through a combined ultrasonic and hydrothermal method, aiming for efficient adsorption of arsenic (As) and fluoride (F-) from drinking water in natural environments. The characterization of HAp-CM was carried out using TG, FTIR, XRD, SEM, SEM-EDS, and TEM techniques, along with the determination of pHpzc charge. FTIR analysis suggested that coordinating links are the main interactions that allow the formation of the nanocomposite. XRD data indicated that the crystalline structure of the constituent materials remained unaffected during the formation of HAp-CM. SEM-EDS analysis revelated a Ca/P molar ratio of 1.78. Adsorption assays conducted in batches demonstrated that As and F- followed a PSO kinetic model. Furthermore, As adsorption fitting well to the Langmuir model, while F- adsorption could be explained by both Langmuir and Freundlich models. The maximum adsorption capacity of HAp-CM was found to be 5.0 mg g-1 for As and 10.2 mg g-1 for F-. The influence of sorbent dosage, pH, and the presence of coexisting species on adsorption capacity was explored. The pH significantly affected the nanocomposite's efficiency in removing both pollutants. The presence of various coexisting species had different effects on F- removal efficiency, while As adsorption efficiency was generally enhanced, except in the case of PO43-. The competitive adsorption between F- and As on HAp-CM was also examined. The achieved results demonstrate that HAp-CM has great potential for use in a natural environment, particularly in groundwater remediation as a preliminary treatment for water consumption.


Assuntos
Arsênio , Durapatita , Fluoretos , Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Fluoretos/química , Adsorção , Nanocompostos/química , Durapatita/química , Poluentes Químicos da Água/química , Arsênio/química , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Biomassa , Cinética , Água Potável/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
2.
J Hazard Mater ; 440: 129737, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988489

RESUMO

In this study, the influence of the plastisphere on metals accumulation and weathering processes of polystyrene (PSMPs) and nylon microplastics (NyMPs) in polluted waters during a 129 day-assay were studied. MPs were characterized through scanning electron microscopy (SEM) with Energy dispersive X-ray (EDX), X-ray diffraction (XRD), attenuated total reflectance Fourier transformed infrared (ATR-FTIR) spectroscopy, contact angle, and thermogravimetric analysis (TGA). Also Cr, Mn, Zn, Cd, Pb, and Cu in the plastisphere on MPs were analyzed during the assay. Potentially pathogenic Vibrio, Escherichia coli, and Pseudomonas spp. were abundant in both MPs. Ascomycota fungi (Phona s.l., Alternaria sp., Penicillium sp., and Cladosporium sp.), and yeast, were also identified. NyMPs and PSMPs exhibited a decrease in the contact angle and increased their weights. SEM/EDX showed weathering signs, like surface cracks and pits, and leaching TiO2 pigments from NyMPs after 42 days. XRD displayed a notorious decrease in NyMPs crystallinity, which could alter its interaction with external contaminants. Heavy metal accumulation on the plastisphere formed on each type of MPs increased over the exposure time. After 129 days of immersion, metals concentrations in the plastisphere on MPs were in the following order Cr ˃ Mn ˃ Zn ˃ Cu ˃ Pb ˃ Cd, demonstrating how the biofilm facilitates metal mobilization. The results of this study lead to a better understanding of the impact of marine plastic debris as vectors of pathogens and heavy metals in coastal environments.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Cádmio/análise , Chumbo , Metais Pesados/análise , Microplásticos , Nylons , Plásticos/química , Poliestirenos/análise , Poluentes Químicos da Água/química
3.
Mar Pollut Bull ; 174: 113276, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35090270

RESUMO

A wide range of contaminants of emerging concern such as micro/nanoplastics (MPs/PNPs) and metal-nanoparticles (Me-NPs) from anthropogenic activities have been identified in aquatic environments. The hazardous effects of these micro/nanomaterials as pollutants in organisms and the lack of knowledge about their behavior in aquatic environments have generated growing concern in the scientific community. The nanomaterials have a colloidal-type behavior due to their size range but with differences in their physicochemical properties. This review comprises the behavior of micro/nanomaterials pollutants and the physicochemical interactions between MPs/PNPs and Me-NPs in aquatic environments, and their potential toxicological effects in organisms. Moreover, this article describes the potential use of Me-NPs to remove MPs/PNPs present in the water column due to their photocatalytic and magnetic properties. It also discusses the challenge to determine harmful effects of micro/nanomaterials pollutants in organisms and provides future research directions to improve integrated management strategies to mitigate their environmental impact.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Nanoestruturas , Poluentes Químicos da Água , Efeitos Antropogênicos , Nanopartículas Metálicas/toxicidade , Nanoestruturas/toxicidade , Poluentes Químicos da Água/toxicidade
4.
AAPS PharmSciTech ; 21(7): 278, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033939

RESUMO

People with weakened immune systems are at risk of developing candidiasis which is a fungal infection caused by several species of Candida genus. In this work, polymeric nanoparticles containing miconazole nitrate and the anesthetic lidocaine clorhydrate were developed. Miconazole was chosen as a typical drug to treat buccopharyngeal candidiasis whereas lidocaine may be useful in the management of the pain burning, and pruritus caused by the infection. Nanoparticles were synthesized using chitosan and gelatin at different ratios ranging from 10:90 to 90:10. The nano-systems presented nanometric size (between 80 and 300 nm in water; with polydispersion index ranging from 0.120 to 0.596), and positive Z potential (between 20.11 and 37.12 mV). The determined encapsulation efficiency ranges from 65 to 99% or 34 to 91% for miconazole nitrate and lidocaine clorhydrate, respectively. X-ray diffraction and DSC analysis suggested that both drugs were in amorphous state in the nanoparticles. Finally, the systems fitted best the Korsmeyer-Peppas model showing that the release from the nanoparticles was through diffusion allowing a sustained release of both drugs and prolonged the activity of miconazole nitrate over time against Candida albicans for at least 24 h.


Assuntos
Candida albicans/isolamento & purificação , Candidíase/tratamento farmacológico , Lidocaína/administração & dosagem , Miconazol/administração & dosagem , Nanopartículas/química , Polímeros/química , Antifúngicos/administração & dosagem , Antifúngicos/química , Varredura Diferencial de Calorimetria , Quitosana , Humanos , Lidocaína/química , Miconazol/química , Nanopartículas/administração & dosagem , Difração de Raios X
6.
Ann Fr Anesth Reanim ; 31(7-8): 638-40, 2012.
Artigo em Francês | MEDLINE | ID: mdl-22749553

RESUMO

We report the case of a 63-year-old patient admitted to the ICU for an acute respiratory failure one week after an outpatient cataract surgery that revealed a nemaline rod myopathy. We present this rare myopathy whose particularities are its aetiology, which can be inherited, mostly with a congenital onset, or sporadic, and the variability of the age at presentation. We discuss the exceptional onset of severe unknown underlying diseases in the context of outpatient surgery.


Assuntos
Diagnóstico Tardio , Miopatias da Nemalina/diagnóstico , Facoemulsificação , Complicações Pós-Operatórias/etiologia , Insuficiência Respiratória/etiologia , Doença Aguda , Neuropatia Alcoólica/complicações , Neuropatia Alcoólica/diagnóstico , Procedimentos Cirúrgicos Ambulatórios , Anestesia Local , Astenia/etiologia , Biópsia , Cardiomiopatia Hipertrófica/complicações , Diagnóstico Diferencial , Eletromiografia , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Miopatias da Nemalina/complicações , Oxigenoterapia , Pneumonia/complicações , Insuficiência Respiratória/terapia
7.
Ann Fr Anesth Reanim ; 28(7-8): 628-33, 2009.
Artigo em Francês | MEDLINE | ID: mdl-19576724

RESUMO

OBJECTIVE: To present the effective applications of paediatric medical simulation in terms of education, evaluation, density, development, goals and constraints. STUDY DESIGN: Survey realized within 38 paediatric simulation centres (PSC) in Europe, identified by Web search and through the Society in Europe for Simulation Applied to Medicine (SESAM. RESULTS: Twenty centers answered the questionnaire (52%). Ninety-four percent of the PSC had beforehand acquired an experience of adult medical simulation, 94.6% of the PSC were created before 2006. Ninety percent of the PSC owned at least one high-fidelity pediatric simulator. The 80% of the PSC indicated multiple funding sources. Eighty percent of the PSC had at least one specific instructor for the paediatric simulation (average=2.7 paediatric instructors per centre). The PCS reported to get onto various topics: neonatology (25% of the PCS), prehospital medicine (36.8%), paediatric anaesthesiology (74%) and paediatric intensive care (89%). Simulation allowed 70% of the centers to lead some research project. Ninety-five percent of the centers agreed about an European collaboration on research projects or about the mutualization of the created scenarios. CONCLUSION: The material, financial and human means of the interviewed centres are consequential but heterogeneous in Europe. MSP offers numerous and various application fields and generates some research activity.


Assuntos
Simulação de Paciente , Pediatria/educação , Pediatria/tendências , Anestesiologia/educação , Anestesiologia/tendências , Criança , Simulação por Computador , Cuidados Críticos/tendências , Serviços Médicos de Emergência , Europa (Continente) , Pesquisas sobre Atenção à Saúde , Humanos , Neonatologia/educação , Neonatologia/tendências , Pediatria/normas , Inquéritos e Questionários
8.
Ann Fr Anesth Reanim ; 25(11-12): 1105-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17045448

RESUMO

OBJECTIVE(S): To assess the content of the intensive care unit (ICU) information booklet delivered to patient families, and that of the general information booklet of the hospital in a sample of intensive care, in France. STUDY DESIGN: Survey. METHODS: A sample of 105 ICU was obtained at random from a national database. A survey form was sent to each ICU medical director. The ICU information booklet, that one from the hospital and the corresponding questionnaire of each participating ICU have been studied to assess the percentage of information items present which matched the recommendations of at least one of three different professional guidelines. RESULTS: Fifty-nine ICU answered. We observed a significant (P<0.01) heterogeneity by the kind ICU considered (general, medical, or surgical). The percentage of information items matching guidelines remained low (median: 41%) even if higher (P<10(-3)) than the percentage of items not matching guidelines (median: 6%). Among a panel of items we considered as important, we observed a significant discrepancy (P<10(-3)) between a low citation rate in ICU booklets (median: 14%) and the opinion of doctors who judged it should included in booklets (median: 68%). CONCLUSION: Guidelines in terms of patient and family information in ICU seem to have a mild impact on the information booklets which are also very different among the types of ICU. There is a gap between what doctors judge to be included in booklets and what they effectively write in these documents.


Assuntos
Unidades de Terapia Intensiva/normas , Folhetos , Relações Profissional-Família , Coleta de Dados , França , Humanos , Recursos Humanos de Enfermagem Hospitalar , Inquéritos e Questionários
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