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1.
Trop Med Int Health ; 22(5): 622-630, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28278352

RESUMO

OBJECTIVES: To investigate and determine the factors that enhanced or constituted barriers to the acceptance of an mHealth system which was piloted in Asante-Akim North District of Ghana to support healthcare of children. METHODS: Four semi-structured focus group discussions were conducted with a total of 37 mothers. Participants were selected from a study population of mothers who subscribed to a pilot mHealth system which used an interactive voice response (IVR) for its operations. Data were evaluated using qualitative content analysis methods. In addition, a short quantitative questionnaire assessed system's usability (SUS). RESULTS: Results revealed 10 categories of factors that facilitated user acceptance of the IVR system including quality-of-care experience, health education and empowerment of women. The eight categories of factors identified as barriers to user acceptance included the lack of human interaction, lack of update and training on the electronic advices provided and lack of social integration of the system into the community. The usability (SUS median: 79.3; range: 65-97.5) of the system was rated acceptable. CONCLUSIONS: The principles of the tested mHealth system could be of interest during infectious disease outbreaks, such as Ebola or Lassa fever, when there might be a special need for disease-specific health information within populations.


Assuntos
Telefone Celular , Acessibilidade aos Serviços de Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Telemedicina/estatística & dados numéricos , Adulto , Criança , Pré-Escolar , Feminino , Gana , Educação em Saúde , Humanos , Lactente , Masculino , Poder Psicológico , Qualidade da Assistência à Saúde , Telemedicina/métodos , Voz , Mulheres
2.
J Appl Microbiol ; 107(3): 1019-30, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19486398

RESUMO

AIMS: Isolation, identification and characterization of an endophytic fungus from Juniperus communis L. Horstmann, as a novel producer of deoxypodophyllotoxin and its in vitro antimicrobial assay. METHODS AND RESULTS: The methodology for the isolation, identification and characterization of a novel endophytic fungus from the twigs of the J. communis L. Horstmann plant, which specifically and consistently produces deoxypodophyllotoxin, was unequivocally established. The fungus was identified as Aspergillus fumigatus Fresenius by molecular, morphological and physiological methods. Deoxypodophyllotoxin was identified and quantified by high-resolution LC-MS, LC-MS(2) and LC-MS(3). The antimicrobial efficacy of the fungal deoxypodophyllotoxin against a panel of pathogenic bacteria was established. CONCLUSIONS: The production of deoxypodophyllotoxin (found in the host) by the cultured endophyte is an enigmatic observation. It demonstrates the transfer of gene(s) for such accumulation by horizontal means from the host plant to its endophytic counterpart. It would be interesting to further study the deoxypodophyllotoxin production and regulation by the cultured endophyte in J. communis and in axenic cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: This endophyte is a potential handle for scientific and commercial exploitation. Although the current accumulation of deoxypodophyllotoxin by the endophyte is not very high, it could be scaled-up to provide adequate production to satisfy new drug development and clinical needs. However, further refined precursor-feeding and mass-balance studies are required to result in the consistent and dependable production.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Aspergillus fumigatus/metabolismo , Juniperus/microbiologia , Podofilotoxina/análogos & derivados , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Aspergillus fumigatus/genética , Aspergillus fumigatus/crescimento & desenvolvimento , Bactérias/efeitos dos fármacos , Cromatografia Líquida , Medicamentos de Ervas Chinesas , Espectrometria de Massas , Micélio/crescimento & desenvolvimento , Podofilotoxina/química , Podofilotoxina/isolamento & purificação , Podofilotoxina/farmacologia , Reação em Cadeia da Polimerase , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
3.
Anal Bioanal Chem ; 391(3): 1029-38, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18414833

RESUMO

An efficient extraction of sulfadiazine residues from soils is difficult, as sulfadiazine is known to form quickly sequestering residues. The objective of this study was to optimize an exhaustive extraction for aged residues of sulfadiazine and its two major metabolites, N-acetylsulfadiazine and 4-hydroxysulfadiazine, from soil. For this purpose two representative used agricultural soils (Luvisol, Cambisol) were blended with manure derived from [(14)C]sulfadiazine-treated pigs and incubated at 10 degrees C in the laboratory. After different extraction tests with various solvent mixtures (two- to four-component mixtures with water, methanol, acetonitrile, acetone, and/or ethyl acetate), different pH values (pH 4 and 9), and extraction temperatures (up to 200 degrees C), soil extracts were measured by liquid scintillation counting and liquid chromatography coupled to tandem mass spectrometry. With respect to sulfadiazine yields, stability of soil extracts, and the amount of coextracted matrix, a microwave extraction of soil (15 min, 150 degrees C) using acetonitrile/water 1:4 (v/v) is the method of choice for the exhaustive extraction of aged sulfadiazine residues from soils.


Assuntos
Micro-Ondas , Solo/análise , Extração em Fase Sólida/métodos , Sulfadiazina/análise , Sulfadiazina/efeitos da radiação , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes
4.
Talanta ; 85(5): 2562-75, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21962684

RESUMO

The identification and quantitative determination of sulfonamidesin solid-state as n-component mixtures is performed. The limits of detection (LODs), accuracy, precision and repeatability are obtained and discussed, using the Raman spectra within 200-30 cm(-1) region (6.00-0.9 THz). The excitations, corresponding to H-bonding deformations, lattice vibrations, as well as coupling modes are used for determination. The validation of the statistical and mathematical tools for procedure of the spectroscopic patterns is performed. The possibilities of baseline correction methods, smoothing procedures, and non-linear curve fitting method for quantitative analysis within THz-region for complex spectroscopic patterns of n-component mixtures (n=1-5) are discussed. The hybrid HPLC tandem mass spectrometry (MS/MS) and powder XRD are applied as independent physical methods for analysis of the studied systems.


Assuntos
Análise Espectral Raman/métodos , Sulfonamidas/análise , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Reprodutibilidade dos Testes
5.
Artigo em Inglês | MEDLINE | ID: mdl-19833548

RESUMO

The novel chloride salt of 1-butyl-4-[2-(4-hydroxyphenyl)ethenyl)]pyridine (1), has been synthesized as the tetrahydrate and its structure and properties elucidated in detail spectroscopically, thermally and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and mass spectrometry. Quantum chemical calculations were performed with a view to supporting and explaining the experimental structural and spectroscopic data. The compound (1) crystallizes in triclinic P1 space group and its unit cell contains two independent 1-butyl-4-[2-(3,5-dimethoxy4-hydroxyphenyl)ethenyl)]pyridinium] cations, differing with respect to the butyl chain torsion angle for which values of 80.0(9) degrees and 173.6(3) degrees are observed. The cations and anions are joined into infinite layers, formed by two different dimers and including solvent molecules. Hydrogen bonds OH...OH(2) (2.814 A), HOH...O(CH(3)) (2.960 A), OH...Cl (2.967 A), HOH...Cl(-) (3.034, 3.188, 3.161 and 3.062 A) and HOH...OH(2) (2.772 A) are observed. For first time in the literature, we are reporting the crystal structure of the dye with the syring-fragment in the molecule. The spectroscopic properties of the novel compound are compared and with those of the corresponding quinoide form (2). Both the forms (1) and (2) are characterized by 21 and 140 nm solvatochromic effects depending of the type of the solvent. The UV-spectroscopic data in solution confirm the formation of classical H-aggregates in polar protic solvent mixture.


Assuntos
Compostos de Piridínio/química , Compostos de Piridínio/síntese química , Cristalografia por Raios X , Modelos Moleculares , Conformação Molecular , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
6.
Environ Sci Technol ; 43(6): 1824-30, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19368178

RESUMO

It is not the total but the (bio)accessible concentration of veterinary medicines that determines their toxicity in the environment. We elucidate the changes in (bio)accessibility of manure-applied sulfadiazine (SDZ) with increasing contact time in soil. Fattening pigs were medicated with 14C-labeled SDZ, and the contaminated manure (fresh and aged) was amended to 2 soil types (Cambisol, Luvisol) and incubated for 218 days at 10 degrees C in the dark. Antibiotic residues of different bioaccessibility were approached by sequential extractions with 0.01 M CaCl2 (CaCl2 fraction), methanol (MeOH fraction), and finally acetonitrile/water (residual fraction, microwave extraction at 150 degrees C). In each fraction, total radioactivity, SDZ, and its major metabolites were quantified. The results showed that both SDZ and,to a lesser extent 4-hydroxysulfadiazine (4-OH-SDZ) were rapidly reformed from N-acetylsulfadiazine (N-ac-SDZ) during the first 2-4 weeks after fresh manure application, i.e., the N-acetylated metabolite does not sequester in soil to a significant extent Yet, the water and methanol extractable SDZ and 4-OH-SDZ also dissipated rapidly (DT50 = 6.0-32 days) for the fresh manure treatment with similar rate constants for both soil types. In the residual fractions, however, the concentrations of both compounds increased with time. We conclude that the residual fraction comprises the sequestered pool of SDZ and its hydroxylated metabolite. There they are entrapped and may persist in soil for several years. Including the residual fraction into fate studies thus yields dissipation half-lives of SDZ which exceed those previously reported for sulfonamides by a factor of about 100.


Assuntos
Resíduos de Drogas/química , Esterco , Poluentes do Solo/química , Sulfadiazina/química , Animais , Solo/análise , Suínos
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