Base de dados : MEDLINE
Pesquisa : D02.262 [Categoria DeCS]
Referências encontradas : 2497 [refinar]
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  1 / 2497 MEDLINE  
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[PMID]:28482284
[Au] Autor:Ranjan B; Pillai S; Permaul K; Singh S
[Ad] Endereço:Department of Biotechnology and Food Technology, Faculty of Applied Sciences, Durban University of Technology, Durban 4000, South Africa.
[Ti] Título:Expression of a novel recombinant cyanate hydratase (rTl-Cyn) in Pichia pastoris, characteristics and applicability in the detoxification of cyanate.
[So] Source:Bioresour Technol;238:582-588, 2017 Aug.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A recombinant Pichia pastoris harbouring the cyanate hydratase gene (rTl-Cyn) from the thermophilic fungus Thermomyces lanuginosus SSBP yielded a high titre of extracellular cyanate hydratase (100±13UmL ) which was ∼10-fold higher than the native fungal strain. The purified rTl-Cyn had a molecular mass of ∼20kDa on SDS-PAGE, with K , V , k and k /K values of 0.34mM, 2857.14µmolesmg min , 2.14×10 s and 6.3 ×10 M s , respectively. Its properties of thermostability, pH stability, and heavy metals insensitivity, make it a suitable candidate for bioremediation in extreme environments. The rTl-Cyn was able to degrade toxic cyanate completely with the liberation of ammonia, which was confirmed by FTIR analysis. This is the first report of any known cyanate hydratase that has been expressed in P. pastoris, characterized and effectively evaluated for cyanate detoxification.
[Mh] Termos MeSH primário: Reatores Biológicos
Cianatos
[Mh] Termos MeSH secundário: Ascomicetos
Clonagem Molecular
Eletroforese em Gel de Poliacrilamida
Concentração de Íons de Hidrogênio
Hidrolases
Pichia
Proteínas Recombinantes
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyanates); 0 (Recombinant Proteins); EC 3.- (Hydrolases)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170509
[St] Status:MEDLINE


  2 / 2497 MEDLINE  
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[PMID]:28438268
[Au] Autor:Bindschedler S; Vu Bouquet TQT; Job D; Joseph E; Junier P
[Ad] Endereço:University of Neuchâtel, Neuchâtel, Switzerland.
[Ti] Título:Fungal Biorecovery of Gold From E-waste.
[So] Source:Adv Appl Microbiol;99:53-81, 2017.
[Is] ISSN:0065-2164
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Waste electric and electronic devices (e-waste) represent a source of valuable raw materials of great interest, and in the case of metals, e-waste might become a prized alternative source. Regarding gold, natural ores are difficult to mine due to their refractory nature and the richest ores have almost all been exploited. Additionally, some gold mining areas are present in geopolitically unstable regions. Finally, the gold mining industry produces toxic compounds, such as cyanides. As a result, the gold present in e-waste represents a nonnegligible resource (urban mining). Extraction methods of gold from natural ores (pyro- and hydrometallurgy) have been adapted to this particular type of matrix. However, to propose novel approaches with a lower environmental footprint, biotechnological methods using microorganisms are being developed (biometallurgy). These processes use the extensive metabolic potential of microbes (algae, bacteria, and fungi) to mobilize and immobilize gold from urban and industrial sources. In this review, we focus on the use of fungi for gold biomining. Fungi interact with gold by mobilizing it through mechanical attack as well as through biochemical leaching by the production of cyanides. Moreover, fungi are also able to release Au through the degradation of cyanide from aurocyanide complexes. Finally, fungi immobilize gold through biosorption, bioaccumulation, and biomineralization, in particular, as gold nanoparticles. Overall, the diversity of mechanisms of gold recycling using fungi combined with their filamentous lifestyle, which allows them to thrive in heterogeneous and solid environments such as e-waste, makes fungi an important bioresource to be harnessed for the biorecovery of gold.
[Mh] Termos MeSH primário: Biotecnologia/métodos
Resíduo Eletrônico/análise
Fungos/metabolismo
Ouro/metabolismo
Reciclagem/métodos
[Mh] Termos MeSH secundário: Biodegradação Ambiental
Cianatos/metabolismo
Fungos/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Cyanates); 03I25JDS1H (gold cyanide); 7440-57-5 (Gold)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170825
[Lr] Data última revisão:
170825
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170426
[St] Status:MEDLINE


  3 / 2497 MEDLINE  
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[PMID]:28415514
[Au] Autor:Kucinska-Lipka J; Gubanska I; Strankowski M; Cieslinski H; Filipowicz N; Janik H
[Ad] Endereço:Gdank University of Technology, Faculty of Chemistry, Department of Polymer Technology, Narutowicza St. 11/12, 80-233 Gdansk, Poland. Electronic address: juskucin@pg.gda.pl.
[Ti] Título:Synthesis and characterization of cycloaliphatic hydrophilic polyurethanes, modified with l-ascorbic acid, as materials for soft tissue regeneration.
[So] Source:Mater Sci Eng C Mater Biol Appl;75:671-681, 2017 Jun 01.
[Is] ISSN:1873-0191
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:In this paper we described synthesis and characteristic of obtained hydrophilic polyurethanes (PURs) modified with ascorbic acid (commonly known as vitamin C). Such materials may find an application in the biomedical field, for example in the regenerative medicine of soft tissues, according to ascorbic acid wide influence on tissue regeneration Flora (2009), Szymanska-Pasternak et al. (2011), Taikarimi and Ibrahim (2011), Myrvik and Volk (1954), Li et al. (2001), Cursino et al. (2005) . Hydrophilic PURs were obtained with the use of amorphous α,ω-dihydroxy(ethylene-butylene adipate) (dHEBA) polyol, 1,4-butanediol (BDO) chain extender and aliphatic 4,4'-methylenebis(cyclohexyl isocyanate) (HMDI). HMDI was chosen as a nontoxic diisocyanate, suitable for biomedical PUR synthesis. Modification with l-ascorbic acid (AA) was performed to improve obtained PUR materials biocompatibility. Chemical structure of obtained PURs was provided and confirmed by Fourier transform infrared spectroscopy (FTIR) and Proton nuclear magnetic resonance spectroscopy ( HNMR). Differential scanning calorimetry (DSC) was used to indicate the influence of ascorbic acid modification on such parameters as glass transition temperature, melting temperature and melting enthalpies of obtained materials. To determine how these materials may potentially behave, after implementation in tissue, degradation behavior of obtained PURs in various chemical environments, which were represented by canola oil, saline solution, distilled water and phosphate buffered saline (PBS) was estimated. The influence of AA on hydrophilic-hydrophobic character of obtained PURs was established by contact angle study. This experiment revealed that ascorbic acid significantly improves hydrophilicity of obtained PUR materials and the same cause that they are more suitable candidates for biomedical applications. Good hemocompatibility characteristic of studied PUR materials was confirmed by the hemocompatibility test with human blood. Microbiological tests were carried out to indicate the microbiological sensitivity of obtained PURs. Results of performed studies showed that obtained AA-modified PUR materials may find an application in soft tissue regeneration.
[Mh] Termos MeSH primário: Ácido Ascórbico
Teste de Materiais
Poliuretanos
Regeneração
[Mh] Termos MeSH secundário: Acrilamidas/química
Ácido Ascórbico/química
Ácido Ascórbico/farmacologia
Butileno Glicóis/química
Cianatos/química
Seres Humanos
Poliuretanos/síntese química
Poliuretanos/química
Poliuretanos/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acrylamides); 0 (Butylene Glycols); 0 (Cyanates); 0 (Polyurethanes); 4CT385M7K2 (methylene bis(4-cyclohexylisocyanate)); 7XOO2LE6G3 (1,4-butanediol); 868-63-3 (N,N'-(1,2-dihydroxyethylene)bisacrylamide); PQ6CK8PD0R (Ascorbic Acid)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170731
[Lr] Data última revisão:
170731
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170419
[St] Status:MEDLINE


  4 / 2497 MEDLINE  
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[PMID]:28400100
[Au] Autor:Pieniazek A; Gwozdzinski K
[Ad] Endereço:Department of Molecular Biophysics, Faculty of Biology and Envirommental Protection, University of Lodz, 90-236 Lodz, Poland. Electronic address: annap@biol.uni.lodz.pl.
[Ti] Título:Carbamylation and oxidation of proteins lead to apoptotic death of lymphocytes.
[So] Source:Chem Biol Interact;270:24-32, 2017 May 25.
[Is] ISSN:1872-7786
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:The apoptotic/necrotic changes in isolated human peripheral blood mononuclear cells (MNCs) subjected to hydrogen peroxide (H O ), cyanate (NaOCN) and their combination were examined. The mitochondrial potential (ΔΨm), the activities of caspases (-2, -3, -6, -8 and -9) and the level of carbonyls and amino groups in proteins were determined and DNA fragmentation. Apoptotic or necrotic cells were identified by fluorescence microscopy using double staining with Hoechst 33258/propidium iodide. Treatment of MNCs with NaOCN (1 mmol/L and 2 mmol/L), alone and in combination with H O (100 µmol/L), led to a significant decrease in the content of amine groups and a significant increase in the carbonyl level of MNCs in comparison with the control. Measurements taken at three time points (30, 60 and 150 min) showed a significant decrease in ΔΨm in MNCs incubated with H O , cyanate and their combination. The highest decrease in ΔΨm was observed after 150 min, when a combination of NaOCN and H O was applied. We observed significant increases in the activities of caspases-2 and -3 in cells exposed to H O and the combination of NaOCN and H O . An increase in caspase-2 but not in caspase-3 activity was noted in cells incubated with cyanate. A significant increase in caspase-9 activity in MNCs was observed in all arrangements of tested compounds in comparison with the control. In H O -treated cells, a higher level of necrotic cells was noted in comparison to apoptotic cells, whereas carbamylation led mainly to apoptotic cell death. The combination of cyanate and H O increased the population of necrotic cells.
[Mh] Termos MeSH primário: Carbamatos/farmacologia
Linfócitos/efeitos dos fármacos
Proteínas/metabolismo
[Mh] Termos MeSH secundário: Apoptose/efeitos dos fármacos
Caspases/metabolismo
Cianatos/toxicidade
Ativação Enzimática/efeitos dos fármacos
Seres Humanos
Peróxido de Hidrogênio/toxicidade
Leucócitos Mononucleares/efeitos dos fármacos
Microscopia de Fluorescência
Oxirredução
Proteínas/efeitos dos fármacos
Padrões de Referência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Carbamates); 0 (Cyanates); 0 (Proteins); BBX060AN9V (Hydrogen Peroxide); EC 3.4.22.- (Caspases)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170524
[Lr] Data última revisão:
170524
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170413
[St] Status:MEDLINE


  5 / 2497 MEDLINE  
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[PMID]:28343358
[Au] Autor:Kebeish R; Al-Zoubi O
[Ad] Endereço:Biology Department, Faculty of Science Yanbu, Taibah University, KSA, King Khalid Rd, Al amoedi, Yanbu El-Bahr, 46423, Saudi Arabia. rkebeish@gmail.com.
[Ti] Título:Expression of the cyanobacterial enzyme cyanase increases cyanate metabolism and cyanate tolerance in Arabidopsis.
[So] Source:Environ Sci Pollut Res Int;24(12):11825-11835, 2017 Apr.
[Is] ISSN:1614-7499
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Cyanate and its derivatives are considered as environmental hazardous materials. Cyanate is released to the environment through many chemical industries and mining wastewater. Cyanase enzyme converts cyanate into CO and NH in a bicarbonate-dependent reaction. At low cyanate concentrations, the endogenous plant cyanases play a vital role in cyanate detoxification. However, such cyanate biodegradation system is probably insufficient due to the excess cyanate concentrations at contaminated sites. In this study, we have transferred the activity of the cyanobacterial cyanase into Arabidopsis thaliana plants in order to enhance plant resistance against cyanate toxicity. The enzyme was shown to be active in planta. Transgenic plants exposed to cyanate, either applied by foliar spray or supplemented in growth medium, showed less reduction in pigment contents, antioxidant enzymes, carbohydrate contents, and reduced levels of plant growth retardation. Plant growth assays under cyanate stress showed enhanced growth and biomass accumulation in cyanase overexpressors compared to control plants. Results of this study provide evidence for developing novel eco-friendly phytoremediation systems for cyanate detoxification.
[Mh] Termos MeSH primário: Arabidopsis/metabolismo
Carbono-Nitrogênio Liases/metabolismo
Cianatos/metabolismo
Cianobactérias/enzimologia
[Mh] Termos MeSH secundário: Arabidopsis/genética
Carbono-Nitrogênio Liases/genética
Plantas Geneticamente Modificadas/genética
Plantas Geneticamente Modificadas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyanates); EC 4.2.1.104 (cyanate hydrolase); EC 4.3.- (Carbon-Nitrogen Lyases)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171103
[Lr] Data última revisão:
171103
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170327
[St] Status:MEDLINE
[do] DOI:10.1007/s11356-017-8866-z


  6 / 2497 MEDLINE  
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[PMID]:27604957
[Au] Autor:Iman M; Kaboutaraki HB; Jafari R; Hosseini SA; Moghimi A; Khamesipour A; Harchegani AB; Davood A
[Ti] Título:Molecular Dynamics Simulation and Docking Studies of Selenocyanate Derivatives as Anti-Leishmanial Agents.
[So] Source:Comb Chem High Throughput Screen;19(10):847-854, 2016.
[Is] ISSN:1875-5402
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Selenocyanate derivatives have been recently presented as potent anti-leishmanial agents. OBJECTIVE: In this research, thirty five selenocyanate and diselenide compounds were subjected to docking studies and compared to Edelfosine and Miltefosine as reference drugs and then molecular dynamics (MD) simulation analysis. METHODS: Desired Selenocyanates were built using the HyperChem program and docking calculations were performed on the crystal structure of trypanothione reductase from Leishmania infantum. Then, MD simulation analysis was performed to explore the interaction stability of selected compound during structural motions of the interacting molecules. RESULTS: Based on the binding energy, all of the aryl rings were more potent than Edelfosine and Miltefosine as reference drug. The best compound base on hydrogen bonding, π-π interactions and orientation within the active site with high binding energy was selected for MD simulation analysis. The selected compound is known as high-affinity selective inhibitor for trypanothione reductase. CONCLUSION: These results can be used for future synthesis of new antileishmanial agents with better potency.
[Mh] Termos MeSH primário: Antiprotozoários/química
Antiprotozoários/farmacologia
Cianatos/química
Cianatos/farmacologia
Leishmania/efeitos dos fármacos
Compostos de Selênio/química
Compostos de Selênio/farmacologia
[Mh] Termos MeSH secundário: Simulação de Acoplamento Molecular
Simulação de Dinâmica Molecular
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antiprotozoal Agents); 0 (Cyanates); 0 (Selenium Compounds); 5749-48-4 (selenocyanic acid)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170622
[Lr] Data última revisão:
170622
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160909
[St] Status:MEDLINE
[do] DOI:10.2174/1386207319666160907102235


  7 / 2497 MEDLINE  
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[PMID]:27591883
[Au] Autor:Gebka K; Beldowski J; Beldowska M
[Ad] Endereço:The Institute of Oceanography, University of Gdansk, Marszalka Pilsudskiego Alley 46, 81-378, Gdynia, Poland. karolinagebka@o2.pl.
[Ti] Título:The impact of military activities on the concentration of mercury in soils of military training grounds and marine sediments.
[So] Source:Environ Sci Pollut Res Int;23(22):23103-23113, 2016 Nov.
[Is] ISSN:1614-7499
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Military activities have been conducted on land and at sea. Both during conflicts and in peace time, some regions served as a military training ground which included firing positions and bunkers. Mercury fulminate has been used in ammunition primers and detonators. Certain amount of ammunition was dumped into the Baltic Sea after the Second World War. Because of corroded containers, mercury can be released into the marine environment. The soil and sediment samples were taken from military training grounds, southern Baltic in 2014 and 2015. The concentration of mercury was determined by AMA-254 analyzer. Hg concentration was higher in the places of military activities, as compared to other areas. Ten times increased concentration of Hg was determined in soil sample collected in area of active gun range compared to the reference station. The significant higher concentration of mercury was detected in stations where chemical warfare agents were found.
[Mh] Termos MeSH primário: Mercúrio/análise
Poluentes do Solo/análise
[Mh] Termos MeSH secundário: Cianatos
Monitoramento Ambiental
Substâncias Explosivas
Sedimentos Geológicos/análise
Militares
Polônia
Solo/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyanates); 0 (Explosive Agents); 0 (Soil); 0 (Soil Pollutants); 628-86-4 (mercury fulminate); FXS1BY2PGL (Mercury)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160905
[St] Status:MEDLINE


  8 / 2497 MEDLINE  
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[PMID]:27525435
[Au] Autor:Koppe L; Nyam E; Vivot K; Manning Fox JE; Dai XQ; Nguyen BN; Trudel D; Attané C; Moullé VS; MacDonald PE; Ghislain J; Poitout V
[Ti] Título:Urea impairs ß cell glycolysis and insulin secretion in chronic kidney disease.
[So] Source:J Clin Invest;126(9):3598-612, 2016 Sep 01.
[Is] ISSN:1558-8238
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Disorders of glucose homeostasis are common in chronic kidney disease (CKD) and are associated with increased mortality, but the mechanisms of impaired insulin secretion in this disease remain unclear. Here, we tested the hypothesis that defective insulin secretion in CKD is caused by a direct effect of urea on pancreatic ß cells. In a murine model in which CKD is induced by 5/6 nephrectomy (CKD mice), we observed defects in glucose-stimulated insulin secretion in vivo and in isolated islets. Similarly, insulin secretion was impaired in normal mouse and human islets that were cultured with disease-relevant concentrations of urea and in islets from normal mice treated orally with urea for 3 weeks. In CKD mouse islets as well as urea-exposed normal islets, we observed an increase in oxidative stress and protein O-GlcNAcylation. Protein O-GlcNAcylation was also observed in pancreatic sections from CKD patients. Impairment of insulin secretion in both CKD mouse and urea-exposed islets was associated with reduced glucose utilization and activity of phosphofructokinase 1 (PFK-1), which could be reversed by inhibiting O-GlcNAcylation. Inhibition of O-GlcNAcylation also restored insulin secretion in both mouse models. These results suggest that insulin secretory defects associated with CKD arise from elevated circulating levels of urea that increase islet protein O-GlcNAcylation and impair glycolysis.
[Mh] Termos MeSH primário: Glicólise
Células Secretoras de Insulina/metabolismo
Insulina/secreção
Falência Renal Crônica/metabolismo
Ureia/química
[Mh] Termos MeSH secundário: Animais
Antioxidantes/metabolismo
Cianatos/química
Modelos Animais de Doenças
Exocitose
Glucoquinase/metabolismo
Glucose/metabolismo
Teste de Tolerância a Glucose
Ilhotas Pancreáticas/metabolismo
Masculino
Camundongos
Camundongos Endogâmicos C57BL
Estresse Oxidativo
Fosfofrutoquinase-1/metabolismo
Espécies Reativas de Oxigênio/metabolismo
Uremia/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antioxidants); 0 (Cyanates); 0 (Insulin); 0 (Reactive Oxygen Species); 8W8T17847W (Urea); EC 2.7.1.11 (Phosphofructokinase-1); EC 2.7.1.2 (Glucokinase); IY9XDZ35W2 (Glucose)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:160816
[St] Status:MEDLINE


  9 / 2497 MEDLINE  
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[PMID]:27357471
[Au] Autor:Jankowski MJ; Olsen R; Thomassen Y; Molander P
[Ad] Endereço:National Institute of Occupational Health, P.O. Box 8149, N-0033, Oslo, Norway. mikolaj.jankowski@stami.no.
[Ti] Título:The stability and generation pattern of thermally formed isocyanic acid (ICA) in air - potential and limitations of proton transfer reaction-mass spectrometry (PTR-MS) for real-time workroom atmosphere measurements.
[So] Source:Environ Sci Process Impacts;18(7):810-8, 2016 Jul 13.
[Is] ISSN:2050-7895
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Isocyanic acid (ICA) in vapour phase has been reported to be of unstable nature, making the occupational hygienic relevance of ICA questionable. The stability of pure ICA in clean air at different humidity conditions was investigated by Fourier transform-infrared spectrometric (FT-IR) measurements. Furthermore, the stability of ICA in a complex atmosphere representative thermal degradation hot-work procedures were examined by performing parallel measurements by proton transfer reaction-mass spectrometric (PTR-MS) instrumentation and off-line denuder air sampling using di-n-butylamine (as a derivatization agent prior to liquid chromatography mass spectrometric (LC-MS) determination). The apparent half-life of ICA in pure ICA atmospheres was 16 to 4 hours at absolute humidity (AH) in the range 4.2 to 14.6 g m(-3), respectively. In a complex atmosphere at an initial AH of 9.6 g m(-3) the apparent half-life of ICA was 8 hours, as measured with the denuder method. Thus, thermally formed ICA is to be considered as a potential occupational hazard with regard to inhalation. The generation pattern of ICA formed during controlled gradient (100-540 °C) thermal decomposition of different polymers in the presence of air was examined by parallel PTR-MS and denuder air sampling. According to measurement by denuder sampling ICA was the dominant aliphatic isocyanate formed during the thermal decomposition of all polymers. The real-time measurements of the decomposed polymers revealed different ICA generation patterns, with initial appearance of thermally released ICA in the temperature range 200-260 °C. The PTR-MS ICA measurements was however affected by mass overlap from other decomposition products at m/z 44, illustrated by a [ICA]Denuder/[ICA]PTR-MS ratio ranging from 0.04 to 0.90. These findings limits the potential use of PTR-MS for real time measurements of thermally released ICA in field, suggesting parallel sampling with short-term sequential off-line methodology.
[Mh] Termos MeSH primário: Poluentes Ocupacionais do Ar/análise
Poluentes Ocupacionais do Ar/química
Poluição do Ar em Ambientes Fechados/análise
Cianatos/química
Prótons
[Mh] Termos MeSH secundário: Cromatografia Líquida
Monitoramento Ambiental
Meia-Vida
Espectrometria de Massas/métodos
Exposição Ocupacional
Espectroscopia de Infravermelho com Transformada de Fourier
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Air Pollutants, Occupational); 0 (Cyanates); 0 (Protons); QKG6U31925 (isocyanic acid)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160701
[St] Status:MEDLINE
[do] DOI:10.1039/c6em00312e


  10 / 2497 MEDLINE  
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[PMID]:27209555
[Au] Autor:Razanamahandry LC; Andrianisa HA; Karoui H; Kouakou KM; Yacouba H
[Ad] Endereço:International Institute for Water and Environmental Engineering (2iE), Department of Water and Sanitary Engineering, Laboratory of Water, Decontamination, Ecosystem and Health (LEDES), 01 PO Box 594, 01, Ouagadougou, Burkina Faso. Electronic address: c.razanamahandry@2ie-edu.org.
[Ti] Título:Biodegradation of free cyanide by bacterial species isolated from cyanide-contaminated artisanal gold mining catchment area in Burkina Faso.
[So] Source:Chemosphere;157:71-8, 2016 Aug.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Soil and water samples were collected from a watershed in Burkina Faso where illegal artisanal gold extraction using cyanidation occurs. The samples were used to evaluate cyanide contamination and the presence of cyanide degrading bacteria (CDB). Free cyanide (F-CN) was detected in all samples, with concentrations varying from 0.023 to 0.9 mg kg(-1), and 0.7-23 µg L(-1) in the soil and water samples, respectively. Potential CDB also were present in the samples. To test the effective F-CN degradation capacity of the isolated CDB species, the species were cultivated in growth media containing 40, 60 or 80 mg F-CN L(-1), with or without nutrients, at pH 9.5 and at room temperature. More than 95% of F-CN was degraded within 25 h, and F-CN degradation was associated with bacterial growth and ammonium production. However, initial concentrations of F-CN higher than 100 mg L(-1) inhibited bacterial growth and cyanide degradation. Abiotic tests showed that less than 3% of F-CN was removed by volatilization. Thus, the degradation of F-CN occurred predominately by biological mechanisms, and such mechanisms are recommended for remediation of contaminated soil and water. The bacteria consortium used in the experiment described above exist in a Sahelian climate, which is characterized by a long hot and dry season. Because the bacteria are already adapted to the local climate conditions and show the potential for cyanide biodegradation, further applicability to other contaminated areas in West Africa, where illegal gold cyanidation is widespread, should be explored.
[Mh] Termos MeSH primário: Bactérias/metabolismo
Biodegradação Ambiental
Cianetos/metabolismo
Ouro
Mineração
[Mh] Termos MeSH secundário: Burkina Faso
Cianatos
Poluição Ambiental/análise
Microbiologia do Solo
Poluentes Químicos da Água/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cyanates); 0 (Cyanides); 0 (Water Pollutants, Chemical); 03I25JDS1H (gold cyanide); 7440-57-5 (Gold)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170817
[Lr] Data última revisão:
170817
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160523
[St] Status:MEDLINE



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