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  1 / 102728 MEDLINE  
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PMID:28333048
Autor:Monapathi ME; Bezuidenhout CC; Rhode OH
Endereço:Unit for Environmental Science and Management - Microbiology, North-West University, Environmental Sciences, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520, South Africa E-mail: carlos.bezuidenhout@nwu.ac.za.
Título:Water quality and antifungal susceptibility of opportunistic yeast pathogens from rivers.
Fonte:Water Sci Technol; 75(5-6):1319-1331, 2017 03.
ISSN:0273-1223
País de publicação:England
Idioma:eng
Resumo:Yeasts from water sources have been associated with diseases ranging from superficial mucosal infections to life threatening diseases. The aim of this study was to determine the water quality as well as diversity and antifungal susceptibility of yeasts from two rivers. Yeast levels and physico-chemical parameter data were analyzed by principal component analysis to determine correlations between physico-chemical data and yeast levels. Yeast morphotypes were identified by biochemical tests and 26S rRNA gene sequencing. Disk diffusion antifungal susceptibility tests were conducted. Physico-chemical parameters of the water were within target water quality range (TWQR) for livestock farming. For irrigational use, total dissolved solids and nitrates were not within the TWQR. Yeast levels ranged between 27 ± 10 and 2,573 ± 306 cfu/L. Only non-pigmented, ascomycetous yeasts were isolated. Saccharomyces cerevisiae and Candida glabrata were most frequently isolated. Several other opportunistic pathogens were also isolated. A large number of isolates were resistant to azoles, especially fluconazole, but also to other antifungal classes. Candida species were resistant to almost all the antifungal classes. These water sources are used for recreation and religious as well as for watering livestock and irrigation. Of particular concern is the direct contact of individuals with opportunistic yeast, especially the immune-compromised. Resistance of these yeast species to antifungal agents is a further health concern.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Antifungal Agents); 8VZV102JFY (Fluconazole)


  2 / 102728 MEDLINE  
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PMID:28272044
Autor:Wasim AA; Khan MN
Endereço:Department of Chemistry, University of Karachi, Karachi 75270, Pakistan E-mail: nasiruk@uok.edu.pk.
Título:Physicochemical effect of activation temperature on the sorption properties of pine shell activated carbon.
Fonte:Water Sci Technol; 75(5-6):1158-1168, 2017 03.
ISSN:0273-1223
País de publicação:England
Idioma:eng
Resumo:Activated carbons produced from a variety of raw materials are normally selective towards a narrow range of pollutants present in wastewater. This study focuses on shifting the selectivity of activated carbon from inorganic to organic pollutants using activation temperature as a variable. The material produced from carbonization of pine shells substrate was activated at 250°C and 850°C. Both adsorbents were compared with commercial activated carbon for the sorption of lead, cadmium, methylene blue, methyl blue, xylenol orange, and crystal violet. It was observed that carbon activated at 250°C was selective for lead and cadmium whereas the one activated at 850°C was selective for the organic dyes. The Fourier transform infrared spectroscopy study revealed that AC850 had less surface functional groups as compared to AC250. Point of zero charge and point of zero salt effect showed that AC250 had acidic groups at its surface. Scanning electron microscopy depicted that increase in activation temperature resulted in an increase in pore size of activated carbon. Both AC250 and AC850 followed pseudo-second-order kinetics. Temkin isotherm model was a best fit for empirical data obtained at equilibrium. The model also showed that sorption process for both AC250 and AC850 was physisorption.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Coloring Agents); 0 (Organic Chemicals); 0 (Phenols); 0 (Salts); 0 (Sulfoxides); 00BH33GNGH (Cadmium); 16291-96-6 (Charcoal); 2P299V784P (Lead); J4Z741D6O5 (Gentian Violet); S2VDY878QD (xylenol orange); T42P99266K (Methylene Blue)


  3 / 102728 MEDLINE  
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PMID:28272039
Autor:Daou I; Zegaoui O; Amachrouq A
Endereço:Equipe de recherche 'Matériaux et Catalyse Appliqués', Laboratoire 'Chimie-Biologie Appliquées à l'Environnement', Faculté des Sciences, Université Moulay Ismaïl, BP. 11201 Zitoune, Meknès, Maroc E-mail: Ikram.chimie@gmail.com.
Título:Study of the effect of an acid treatment of a natural Moroccan bentonite on its physicochemical and adsorption properties.
Fonte:Water Sci Technol; 75(5-6):1098-1117, 2017 03.
ISSN:0273-1223
País de publicação:England
Idioma:eng
Resumo:In this study, a natural bentonite taken from a deposit in the Northeast of Morocco has been purified (PB) and treated with various HCl molarities (xHPB) in order to obtain an HCl/Bentonite weight ratio equal to 0.2, 0.4 and 0.6. The obtained physicochemical characterization results indicated that the PB sample is composed mainly of the montmorillonite phase. The impact of acid treatment was investigated by identifying changes in the chemical composition, cation exchange capacity, infrared absorption bands, crystalline structure, morphology of the particles and specific surface area. The adsorption behavior of methylene blue (MB) and methyl orange (MO) in aqueous solution onto PB and xHPB samples was investigated by varying the initial concentration of dyes, the contact time and the temperature. The obtained results showed that the experimental data best fit the Langmuir model and the pseudo-second-order kinetic model. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) studies carried out after MB and MO adsorption onto PB samples indicated that MB cations were intercalated, in the form of monomers and dimers, with a large amount of monomers, slightly tilted against the plane of the clay surface. While MO molecules adsorb, with a near perpendicular alignment, with their SO group and O atoms facing the mineral surface plane.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Azo Compounds); 0 (Cations); 1302-78-9 (Bentonite); 6B4TC34456 (methyl orange); QTT17582CB (Hydrochloric Acid); T42P99266K (Methylene Blue)


  4 / 102728 MEDLINE  
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PMID:28161849
Autor:Orruño M; Kaberdin VR; Arana I
Endereço:Department of Immunology, Microbiology and Parasitology, University of the Basque Country (UPV/EHU), Barrio Sarriena S/n, 48940, Leioa, Spain.
Título:Survival strategies of Escherichia coli and Vibrio spp.: contribution of the viable but nonculturable phenotype to their stress-resistance and persistence in adverse environments.
Fonte:World J Microbiol Biotechnol; 33(3):45, 2017 Mar.
ISSN:1573-0972
País de publicação:Germany
Idioma:eng
Resumo:In their natural ecosystems, bacteria are continuously exposed to changing environmental factors including physicochemical parameters (e.g. temperature, pH, etc.), availability of nutrients as well as interaction(s) with other organisms. To increase their tolerance and survival under adverse conditions, bacteria trigger a number of adaptation mechanisms. One of the well-known adaptation responses of the non-spore-forming bacteria is the acquisition of the viable but non-culturable (VBNC) state. This phenotype is induced by different stress factors (e.g. low temperature) and is characterized by the temporal loss of culturability, which can potentially be restored. Moreover, this response can be combined with the bust and boom strategy, which implies the death of the main population of the stressed cells (or their entry into the VBNC state) upon stress, thus enabling the remaining cells (i.e. residual culturable population) to subsist at the expense of the dead or/and VBNC cells. In this review, we discuss the characteristics of the VBNC state, its biological significance and contribution to bacterial survival.
Tipo de publicação: JOURNAL ARTICLE; REVIEW


  5 / 102728 MEDLINE  
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PMID:28867759
Autor:Kadhum WR; Hada T; Hijikuro I; Todo H; Sugibayashi K
Endereço:Faculty of Pharmacy and Pharmaceutical Sciences, Josai University.
Título:Development and Optimization of Orally and Topically Applied Liquid Crystal Drug Formulations.
Fonte:J Oleo Sci; 66(9):939-950, 2017.
ISSN:1347-3352
País de publicação:Japan
Idioma:eng
Resumo:Liquid crystal (LC)-forming lipids represent an important class of biocompatible amphiphiles and their application extends to cosmeceutical, dietary, and pharmaceutical technologies. In the present study, we aimed to develop strategies for designing and optimizing oral and topical LC formulations by evaluating their in vitro and in vivo drug absorption performances. C -Monoglycerol ester (MGE) was used as a LC-forming lipid. p-Amino benzoic acid, methyl PABA, ethyl PABA, and sodium fluorescein were selected as drug models with different physiochemical properties. Various oral and topical LC formulations were designed based on changes in the LC forming lipid contents in the formulations and entrapped with different physiochemical properties of the drugs. The LC phase structures were evaluated using small-angle X-ray scattering (SAXS). The drug-release profiles from LC formulations were determined using a dialysis membrane method. In vivo oral absorption of LC formulations was conducted in Wistar rats. Furthermore, the skin penetration of drugs from LC formulations was investigated by in vitro skin permeation studies. As a result, although the release profile was influenced by changes in MGE concentration, it was more dramatically influenced by changes in the physiochemical properties of the entrapped drugs. Drug absorption after oral and topical administration of LC formulations was dramatically affected by the concentration of MGE. The concentration of LC-forming lipid and the physiochemical properties of entrapped drugs are key issues for good performance of the LC formulations in various pharmaceutical applications. The present results could enable researchers to manipulate LC formulation approaches intended to improve the oral absorption and skin permeation of drugs.
Tipo de publicação: JOURNAL ARTICLE


  6 / 102728 MEDLINE  
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PMID:28764089
Autor:Zhu D; Wei H; Guo B; Dai Q; Wei C; Gao H; Hu Y; Cui P; Li M; Huo Z; Xu K; Zhang H
Endereço:Jiangsu Key Laboratory of Crop Genetics and Physiology & Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou, Jiangsu, China.
Título:The effects of chilling stress after anthesis on the physicochemical properties of rice (Oryza sativa L) starch.
Fonte:Food Chem; 237:936-941, 2017 Dec 15.
ISSN:0308-8146
País de publicação:England
Idioma:eng
Resumo:This study investigates the effect of chilling stress, over a period of three days after anthesis, on the physicochemical properties of starches derived from six rice cultivars. Chilling stress significantly affected the grain characteristics and physicochemical properties of rice starches, except for those of two varieties, NJ 9108 and ZD 18. In the other four rice cultivars subjected to chilling stress, the content of medium, and large sized granules showed a decrease, and an increase, respectively. Amylose content increased as a result of chilling stress, thereby resulting in starch with a lower swelling power, water solubility, and higher retrogradation enthalpy and gelatinization temperature. Chilling stress led to deterioration of cooked rice quality as determined by the pasting properties of starch. This study indicated that among the cultivars studied, the two rice varieties most resistant to chilling stress after rice anthesis were NJ 9108 and ZD 18.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:9005-25-8 (Starch); 9005-82-7 (Amylose)


  7 / 102728 MEDLINE  
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PMID:28855095
Autor:Hvidsten I; Mjøs SA; Holmelid B; Bødtker G; Barth T
Endereço:Department of Chemistry, University of Bergen, Allégaten 41, 5007 Bergen, Norway. Electronic address: ina.hvidsten@kj.uib.no.
Título:Lipids of Dietzia sp. A14101. Part I: A study of the production dynamics of surface-active compounds.
Fonte:Chem Phys Lipids; 208:19-30, 2017 Nov.
ISSN:1873-2941
País de publicação:Ireland
Idioma:eng
Resumo:Dietzia sp. A14101 belonging to the genus Dietzia (Gram-positive bacteria, Actinomycetes, high G+C content of DNA) was isolated from an oil reservoir model column inoculated with oil-field bacteria (Bødtker et al., 2009). Low interfacial tension (IFT) values were obtained by studying intact strain cells grown on water-immiscible hydrocarbons (HC) (Kowalewski et al. (2004), Kowalewski et al. (2005). Further investigations showed that the adaptation mechanism of Dietzia sp. A14101 to toxic water-immiscible HC involved changes both on the level of fatty acids content and in the physical properties of the cellular surface (development of the negative cellular surface charge and an increased in hydrophobicity) (Hvidsten et al., 2015b). However, these changes could not explain the low IFT values observed in earlier studies of this strain. Generally, low IFT imply a production of surface active compounds of low MW that are lipids by structure (Rosenberg and Ron, 1999). In this paper, it is shown that Dietzia sp. A14101 produces a range of glycolipids on all substrates. The amount of trehalose-containing lipids increases when the strain is grown on hydrocarbons. The production peak seems to coincide with the exponential growth phase, and such increased glycolipid synthesis continues throughout the stationary phase. The results indicate that only low amounts of the hydrocarbon substrate is incorporated directly into the glycolipids produced. Most of the hydrocarbon substrate seems to be employed for the biosynthesis of the neutral lipids and higher amounts of biomass were generated on HC substrates compared to incubations on non-HC substrates. The lipid content of the cell was determined as the total lipid extract (TLE), and was further fractionated (SPE). The hydrophobic and hydrophilic moieties of the isolated surface active compounds were determined (GC-MS, TLC, DART, LC-MS). The changes in the lipid content during the culture development were monitored by 1D and 2D TLC, emulsification and oil-spreading tests.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Fatty Acids); 0 (Glycolipids); 0 (Surface-Active Agents)


  8 / 102728 MEDLINE  
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PMID:28768950
Autor:Ito I; Ito A; Unezaki S
Endereço:Department of Practical Pharmacy, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences.
Título:Investigation of Oral Preparation That Is Expected to Improve Medication Administration: Preparation and Evaluation of Oral Gelling Tablet Using Sodium Alginate.
Fonte:Yakugaku Zasshi; 137(8):969-977, 2017.
ISSN:1347-5231
País de publicação:Japan
Idioma:jpn
Resumo:We investigated the preparation of a gelling tablet that swells and forms a gel upon absorbing water, and hence would be easy for patients to swallow. We prepared naked tablets and compressed coated tablets by the direct tableting or wet granule-compression methods, using the commonly prescribed drug acetaminophen (AA) and sodium alginate (AG) as a thickening agent. The tablets quickly absorbed water, had favorable gelling properties, low adhesiveness, appropriate drug dissolution profile, and at the same time, were easy to swallow. In the case of naked tablets, water absorption increased upon granulation, but gelling of AG interfere when AA and AG were present together. There was no change in the adhesiveness, and more than 30 min were required to achieve a 25% dissolution ratio. Compressed coated tablets that were made with AA in the inner layer and granulated AG in the outer layer showed improved dissolution behavior, it was about 90% dissolution ratio in 30 min, owing to the water absorption property of AG, and decreased adhesiveness. In this case, there was a difference in the outer layer thickness. As the outer layer amount increased, dissolution slowed, but it did not depend on the compression pressure. Our gelling tablet can be prepared by using AA (main drug) in the inner layer and an appropriate thickness of granulated AG in the outer layer of compressed coated tablets.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Alginates); 0 (Excipients); 0 (Gels); 0 (Hexuronic Acids); 0 (Tablets); 362O9ITL9D (Acetaminophen); 8A5D83Q4RW (Glucuronic Acid); 8C3Z4148WZ (alginic acid)


  9 / 102728 MEDLINE  
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PMID:28255348
Autor:Chen B; Dai W; He B; Zhang H; Wang X; Wang Y; Zhang Q
Endereço:Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China; State Key Laboratory of Natural and Biomimetic Drugs, Beijing 100191, China.
Título:Current Multistage Drug Delivery Systems Based on the Tumor Microenvironment.
Fonte:Theranostics; 7(3):538-558, 2017.
ISSN:1838-7640
País de publicação:Australia
Idioma:eng
Resumo:The development of traditional tumor-targeted drug delivery systems based on EPR effect and receptor-mediated endocytosis is very challenging probably because of the biological complexity of tumors as well as the limitations in the design of the functional nano-sized delivery systems. Recently, multistage drug delivery systems (Ms-DDS) triggered by various specific tumor microenvironment stimuli have emerged for tumor therapy and imaging. In response to the differences in the physiological blood circulation, tumor microenvironment, and intracellular environment, Ms-DDS can change their physicochemical properties (such as size, hydrophobicity, or zeta potential) to achieve deeper tumor penetration, enhanced cellular uptake, timely drug release, as well as effective endosomal escape. Based on these mechanisms, Ms-DDS could deliver maximum quantity of drugs to the therapeutic targets including tumor tissues, cells, and subcellular organelles and eventually exhibit the highest therapeutic efficacy. In this review, we expatiate on various responsive modes triggered by the tumor microenvironment stimuli, introduce recent advances in multistage nanoparticle systems, especially the multi-stimuli responsive delivery systems, and discuss their functions, effects, and prospects.
Tipo de publicação: JOURNAL ARTICLE; REVIEW
Nome de substância:0 (Antineoplastic Agents)


  10 / 102728 MEDLINE  
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PMID:28985945
Autor:Rahman L; Jacobsen NR; Aziz SA; Wu D; Williams A; Yauk CL; White P; Wallin H; Vogel U; Halappanavar S
Endereço:Environmental Health Science and Research Bureau, Health Canada, Ottawa, Canada.
Título:Multi-walled carbon nanotube-induced genotoxic, inflammatory and pro-fibrotic responses in mice: Investigating the mechanisms of pulmonary carcinogenesis.
Fonte:Mutat Res; 823:28-44, 2017 Nov.
ISSN:1873-135X
País de publicação:Netherlands
Idioma:eng
Resumo:The International Agency for Research on Cancer has classified one type of multi-walled carbon nanotubes (MWCNTs) as possibly carcinogenic to humans. However, the underlying mechanisms of MWCNT- induced carcinogenicity are not known. In this study, the genotoxic, mutagenic, inflammatory, and fibrotic potential of MWCNTs were investigated. Muta™Mouse adult females were exposed to 36±6 or 109±18µg/mouse of Mitsui-7, or 26±2 or 78±5µg/mouse of NM-401, once a week for four consecutive weeks via intratracheal instillations, alongside vehicle-treated controls. Samples were collected 90days following the first exposure for measurement of DNA strand breaks, lacZ mutant frequency, p53 expression, cell proliferation, lung inflammation, histopathology, and changes in global gene expression. Both MWCNT types persisted in lung tissues 90days post-exposure, and induced lung inflammation and fibrosis to similar extents. However, there was no evidence of DNA damage as measured by the comet assay following Mitsui-7 exposure, or increases in lacZ mutant frequency, for either MWCNTs. Increased p53 expression was observed in the fibrotic foci induced by both MWCNTs. Gene expression analysis revealed perturbations of a number of biological processes associated with cancer including cell death, cell proliferation, free radical scavenging, and others in both groups, with the largest response in NM-401-treated mice. The results suggest that if the two MWCNT types were capable of inducing DNA damage, strong adaptive responses mounted against the damage, resulting in efficient and timely elimination of damaged cells through cell death, may have prevented accumulation of DNA damage and mutations at the post-exposure time point investigated in the study. Thus, MWCNT-induced carcinogenesis may involve ongoing low levels of DNA damage in an environment of persisting fibres, chronic inflammation and tissue irritation, and parallel increases or decreases in the expression of genes involved in several pro-carcinogenic pathways.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Nanotubes, Carbon); 0 (Tumor Suppressor Protein p53)



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