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1 / 2077

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[PMID]: 28902532 [Au] Autor: Peters AL; Veldthuis M; van Leeuwen K; Bossuyt PMM; Vlaar APJ; van Bruggen R; de Korte D; Van Noorden CJF; van Zwieten R [Ad] Endereço: Department of Intensive Care, Academic Medical Centre, Amsterdam, The Netherlands. [Ti] Título: Comparison of Spectrophotometry, Chromate Inhibition, and Cytofluorometry Versus Gene Sequencing for Detection of Heterozygously Glucose-6-Phosphate Dehydrogenase-Deficient Females. [So] Source: J Histochem Cytochem;65(11):627-636, 2017 Nov. [Is] ISSN: 1551-5044 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme deficiency worldwide. Detection of heterozygously deficient females can be difficult as residual activity in G6PD-sufficient red blood cells (RBCs) can mask deficiency. In this study, we compared accuracy of 4 methods for detection of G6PD deficiency in females. Blood samples from females more than 3 months of age were used for spectrophotometric measurement of G6PD activity and for determination of the percentage G6PD-negative RBCs by cytofluorometry. An additional sample from females suspected to have G6PD deficiency based on the spectrophotometric G6PD activity was used for measuring chromate inhibition and sequencing of the G6PD gene. Of 165 included females, 114 were suspected to have heterozygous deficiency. From 75 females, an extra sample was obtained. In this group, mutation analysis detected 27 heterozygously deficient females. The sensitivity of spectrophotometry, cytofluorometry, and chromate inhibition was calculated to be 0.52 (confidence interval [CI]: 0.32-0.71), 0.85 (CI: 0.66-0.96), and 0.96 (CI: 0.71-1.00, respectively, and the specificity was 1.00 (CI: 0.93-1.00), 0.88 (CI: 0.75-0.95), and 0.98 (CI: 0.89-1.00), respectively. Heterozygously G6PD-deficient females with a larger percentage of G6PD-sufficient RBCs are missed by routine methods measuring total G6PD activity. However, the majority of these females can be detected with both chromate inhibition and cytofluorometry. [Mh] Termos MeSH primário: Cromatos/antagonistas & inibidores Citometria de Fluxo/métodos Deficiência de Glucosefosfato Desidrogenase/diagnóstico Glucosefosfato Desidrogenase/genética Heterozigoto Espectrofotometria/métodos [Mh] Termos MeSH secundário: Feminino Deficiência de Glucosefosfato Desidrogenase/genética Seres Humanos Lactente [Pt] Tipo de publicação: COMPARATIVE STUDY; JOURNAL ARTICLE [Nm] Nome de substância: 0 (Chromates); EC 1.1.1.49 (Glucosephosphate Dehydrogenase) [Em] Mês de entrada: 1711 [Cu] Atualização por classe: 171110 [Lr] Data última revisão: 171110 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170914 [St] Status: MEDLINE [do] DOI: 10.1369/0022155417730021

2 / 2077

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[PMID]: 28759204 [Au] Autor: Krawic C; Luczak MW; Zhitkovich A [Ad] Endereço: Department of Pathology and Laboratory Medicine, Brown University , 70 Ship Street, Providence, Rhode Island 02912, United States. [Ti] Título: Variation in Extracellular Detoxification Is a Link to Different Carcinogenicity among Chromates in Rodent and Human Lungs. [So] Source: Chem Res Toxicol;30(9):1720-1729, 2017 Sep 18. [Is] ISSN: 1520-5010 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Inhalation of soluble chromium(VI) is firmly linked with higher risks of lung cancer in humans. However, comparative studies in rats have found a high lung tumorigenicity for moderately soluble chromates but no tumors for highly soluble chromates. These major species differences remain unexplained. We investigated the impact of extracellular reducers on responses of human and rat lung epithelial cells to different Cr(VI) forms. Extracellular reduction of Cr(VI) is a detoxification process, and rat and human lung lining fluids contain different concentrations of ascorbate and glutathione. We found that reduction of chromate anions in simulated lung fluids was principally driven by ascorbate with only minimal contribution from glutathione. The addition of 500 µM ascorbate (∼rat lung fluid concentration) to culture media strongly inhibited cellular uptake of chromate anions and completely prevented their cytotoxicity even at otherwise lethal doses. While proportionally less effective, 50 µM extracellular ascorbate (∼human lung fluid concentration) also decreased uptake of chromate anions and their cytotoxicity. In comparison to chromate anions, uptake and cytotoxicity of respirable particles of moderately soluble CaCrO and SrCrO were much less sensitive to suppression by extracellular ascorbate, especially during early exposure times and in primary bronchial cells. In the absence of extracellular ascorbate, chromate anions and CaCrO /SrCrO particles produced overall similar levels of DNA double-stranded breaks, with less soluble particles exhibiting a slower rate of breakage. Our results indicate that a gradual extracellular dissolution and a rapid internalization of calcium chromate and strontium chromate particles makes them resistant to detoxification outside the cells, which is extremely effective for chromate anions in the rat lung fluid. The detoxification potential of the human lung fluid is significant but much lower and insufficient to provide a threshold-type dose dependence for soluble chromates. [Mh] Termos MeSH primário: Cromatos/toxicidade Pulmão/efeitos dos fármacos [Mh] Termos MeSH secundário: Animais Ácido Ascórbico/química Compostos de Cálcio/química Compostos de Cálcio/metabolismo Compostos de Cálcio/toxicidade Linhagem Celular Sobrevivência Celular/efeitos dos fármacos Cromatos/química Cromatos/metabolismo Quebras de DNA de Cadeia Dupla/efeitos dos fármacos Glutationa/química Seres Humanos Pulmão/patologia Oxirredução Ratos Estrôncio/química Estrôncio/metabolismo Estrôncio/toxicidade [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Calcium Compounds); 0 (Chromates); 2W214M3GS2 (strontium chromate); GAN16C9B8O (Glutathione); J1FGH4ZJ4M (calcium chromate(VI)); PQ6CK8PD0R (Ascorbic Acid); YZS2RPE8LE (Strontium) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 171122 [Lr] Data última revisão: 171122 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170801 [St] Status: MEDLINE [do] DOI: 10.1021/acs.chemrestox.7b00172

3 / 2077

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[PMID]: 28554658 [Au] Autor: Browning CL; Wise JP [Ad] Endereço: Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, United States; Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME 04469, United States. Electronic address: cynthia_browning@brown.edu. [Ti] Título: Prolonged exposure to particulate chromate inhibits RAD51 nuclear import mediator proteins. [So] Source: Toxicol Appl Pharmacol;331:101-107, 2017 Sep 15. [Is] ISSN: 1096-0333 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Particulate hexavalent chromium (Cr(VI)) is a human lung carcinogen and a human health concern. The induction of structural chromosome instability is considered to be a driving mechanism of Cr(VI)-induced carcinogenesis. Homologous recombination repair protects against Cr(VI)-induced chromosome damage, due to its highly accurate repair of Cr(VI)-induced DNA double strand breaks. However, recent studies demonstrate Cr(VI) inhibits homologous recombination repair through the misregulation of RAD51. RAD51 is an essential protein in HR repair that facilitates the search for a homologous sequence. Recent studies show prolonged Cr(VI) exposure prevents proper RAD51 subcellular localization, causing it to accumulate in the cytoplasm. Since nuclear import of RAD51 is crucial to its function, this study investigated the effect of Cr(VI) on the RAD51 nuclear import mediators, RAD51C and BRCA2. We show acute (24h) Cr(VI) exposure induces the proper localization of RAD51C and BRCA2. In contrast, prolonged (120h) exposure increased the cytoplasmic localization of both proteins, although RAD51C localization was more severely impaired. These results correlate temporally with the previously reported Cr(VI)-induced RAD51 cytoplasmic accumulation. In addition, we found Cr(VI) does not inhibit interaction between RAD51 and its nuclear import mediators. Altogether, our results suggest prolonged Cr(VI) exposure inhibits the nuclear import of RAD51C, and to a lesser extent, BRCA2, which results in the cytoplasmic accumulation of RAD51. Cr(VI)-induced inhibition of nuclear import may play a key role in its carcinogenic mechanism since the nuclear import of many tumor suppressor proteins and DNA repair proteins is crucial to their function. [Mh] Termos MeSH primário: Transporte Ativo do Núcleo Celular/efeitos dos fármacos Cromatos/toxicidade Material Particulado/toxicidade Rad51 Recombinase/antagonistas & inibidores Rad51 Recombinase/metabolismo Compostos de Zinco/toxicidade [Mh] Termos MeSH secundário: Transporte Ativo do Núcleo Celular/fisiologia Animais Linhagem Celular Transformada Cromatos/administração & dosagem Cricetinae Cricetulus Dano ao DNA/efeitos dos fármacos Dano ao DNA/fisiologia Proteínas de Ligação a DNA/antagonistas & inibidores Proteínas de Ligação a DNA/metabolismo Relação Dose-Resposta a Droga Seres Humanos Material Particulado/administração & dosagem Proteínas Supressoras de Tumor/antagonistas & inibidores Proteínas Supressoras de Tumor/metabolismo Compostos de Zinco/administração & dosagem [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Chromates); 0 (DNA-Binding Proteins); 0 (Particulate Matter); 0 (Tumor Suppressor Proteins); 0 (Zinc Compounds); 05F2837HUF (zinc chromate); EC 2.7.7.- (RAD51 protein, human); EC 2.7.7.- (Rad51 Recombinase) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170904 [Lr] Data última revisão: 170904 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170531 [St] Status: MEDLINE

4 / 2077

MEDLINE

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[PMID]: 28494363 [Au] Autor: Zhou X; Zhou M; Wu X; Han Y; Geng J; Wang T; Wan S; Hou H [Ad] Endereço: School of Resource and Environmental Science, Wuhan University, Wuhan, Hubei, 430072, PR China. [Ti] Título: Reductive solidification/stabilization of chromate in municipal solid waste incineration fly ash by ascorbic acid and blast furnace slag. [So] Source: Chemosphere;182:76-84, 2017 Sep. [Is] ISSN: 1879-1298 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Fly ash is a hazardous byproduct of municipal solid waste incineration (MSWI). Cementitious material that is based on ground-granulated blast furnace slag (GGBFS) has been tested and proposed as a binder to stabilize Pb, Cd, and Zn in MSWI fly ash (FA). Cr, however, still easily leaches from MSWI FA. Different reagents, such as ascorbic acid (VC), NaAlO , and trisodium salt nonahydrate, were investigated as potential Cr stabilizers. The results of the toxicity characteristic leaching procedure (TCLP) showed that VC significantly improved the stabilization of Cr via the reduction of Cr(VI) to Cr(III). VC, however, could interfere with the hydration process. Most available Cr was transformed into stable Cr forms at the optimum VC content of 2 wt%. Cr leaching was strongly pH dependent and could be represented by a quintic polynomial model. The results of X-ray diffraction and scanning electron microscopy-energy dispersive analysis revealed that hollow spheres in raw FA were partially filled with hydration products, resulting in the dense and homogeneous microstructure of the solidified samples. The crystal structures of C-S-H and ettringite retained Zn and Cr ions. In summary, GGBFS-based cementitious material with the low addition of 2 wt% VC effectively immobilizes Cr-bearing MSWI FA. [Mh] Termos MeSH primário: Ácido Ascórbico Cromatos/isolamento & purificação Cinza de Carvão/química Incineração/métodos Resíduos Sólidos [Mh] Termos MeSH secundário: Carbono/química Cromatos/química Metais Pesados Microscopia Eletrônica de Varredura Material Particulado Eliminação de Resíduos/métodos Difração de Raios X [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Chromates); 0 (Coal Ash); 0 (Metals, Heavy); 0 (Particulate Matter); 0 (Solid Waste); 7440-44-0 (Carbon); PQ6CK8PD0R (Ascorbic Acid) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170921 [Lr] Data última revisão: 170921 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170512 [St] Status: MEDLINE

5 / 2077

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[PMID]: 28411036 [Au] Autor: Browning CL; Wise CF; Wise JP [Ad] Endereço: Wise Laboratory of Environmental and Genetic Toxicology, Department of Pharmacology and Toxicology, University of Louisville School of Medicine, 505 S Hancock St, CTRB, Louisville, KY 40292, USA; Graduate School of Biomedical Science and Engineering, University of Maine, 42 Stodder Hall, Orono, ME 04469, USA. [Ti] Título: Prolonged particulate chromate exposure does not inhibit homologous recombination repair in North Atlantic right whale (Eubalaena glacialis) lung cells. [So] Source: Toxicol Appl Pharmacol;331:18-23, 2017 Sep 15. [Is] ISSN: 1096-0333 [Cp] País de publicação: United States [La] Idioma: eng [Ab] Resumo: Chromosome instability is a common feature of cancers that forms due to the misrepair of DNA double strand breaks. Homologous recombination (HR) repair is a high fidelity DNA repair pathway that utilizes a homologous DNA sequence to accurately repair such damage and protect the genome. Prolonged exposure (>72h) to the human lung carcinogen, particulate hexavalent chromium (Cr(VI)), inhibits HR repair, resulting in increased chromosome instability in human cells. Comparative studies have shown acute Cr(VI) exposure induces less chromosome damage in whale cells than human cells, suggesting investigating the effect of this carcinogen in other species may inform efforts to prevent Cr(VI)-induced chromosome instability. Thus, the goal of this study was to determine the effect of prolonged Cr(VI) exposure on HR repair and clastogenesis in North Atlantic right whale (Eubalaena glacialis) lung cells. We show particulate Cr(VI) induces HR repair activity after both acute (24h) and prolonged (120h) exposure in North Atlantic right whale cells. Although the RAD51 response was lower following prolonged Cr(VI) exposure compared to acute exposure, the response was sufficient for HR repair to occur. In accordance with active HR repair, no increase in Cr(VI)-induced clastogenesis was observed with increased exposure time. These results suggest prolonged Cr(VI) exposure affects HR repair and genomic stability differently in whale and human lung cells. Future investigation of the differences in how human and whale cells respond to chemical carcinogens may provide valuable insight into mechanisms of preventing chemical carcinogenesis. [Mh] Termos MeSH primário: Cromatos/toxicidade Pulmão/citologia Pulmão/efeitos dos fármacos Material Particulado/toxicidade Reparo de DNA por Recombinação/efeitos dos fármacos Compostos de Zinco/toxicidade [Mh] Termos MeSH secundário: Animais Sobrevivência Celular/efeitos dos fármacos Sobrevivência Celular/fisiologia Células Cultivadas Cromatos/administração & dosagem Relação Dose-Resposta a Droga Pulmão/fisiologia Material Particulado/administração & dosagem Reparo de DNA por Recombinação/fisiologia Mucosa Respiratória/efeitos dos fármacos Mucosa Respiratória/fisiologia Fatores de Tempo Baleias Compostos de Zinco/administração & dosagem [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Chromates); 0 (Particulate Matter); 0 (Zinc Compounds); 05F2837HUF (zinc chromate) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 171003 [Lr] Data última revisão: 171003 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170416 [St] Status: MEDLINE

6 / 2077

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[PMID]: 28402295 [Au] Autor: Chen J; Zhang X; Han J; Li Y; Su M; Lu A [Ad] Endereço: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, China E-mail: chjx2000@126.com. [Ti] Título: Kinetics and mechanism of desilication reaction in sodium chromate solution using sodium aluminate. [So] Source: Water Sci Technol;75(7-8):1548-1554, 2017 Apr. [Is] ISSN: 0273-1223 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: It is essential to control silica levels in sodium chromate solution during the process of electrolytic synthesis of sodium dichromate. On the basis of previous work, the desilication conditions were systematically studied and pH was found to have the most serious impact on the desilication process. The desilication rate under optimal conditions obtained from the orthogonal experiment results was up to 99.3%. Kinetic experiments showed that the desilication reaction was first-order in SiO concentration and the apparent activation energy was calculated to be 22 kJ mol , which is far less than the reported values. The morphology and structure of the desilication reaction product (DSP) were studied by scanning electron microscope (SEM) and X-ray diffraction (XRD). SEM showed that DSP had a loose etched structure. The pattern of XRD illustrated the crystallinity of DSP increased along the duration of the experiment. The phase of DSP was mainly Na (AlSiO ) . Based on the experimental data, the desilication mechanism has been discussed. The hexameric aluminosilicate ions were produced by the reaction of monomeric aluminosilicate ion, through hydrogen bond interaction, which was formed by SiO (OH) and Al(OH) . [Mh] Termos MeSH primário: Compostos de Alumínio/química Cromatos/química Dióxido de Silício/química Compostos de Sódio/química [Mh] Termos MeSH secundário: Concentração de Íons de Hidrogênio Cinética Soluções Difração de Raios X [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Aluminum Compounds); 0 (Chromates); 0 (Sodium Compounds); 0 (Solutions); 0 (sodium aluminate); 6A49BO6K4M (sodium chromate(VI)); 7631-86-9 (Silicon Dioxide) [Em] Mês de entrada: 1709 [Cu] Atualização por classe: 170919 [Lr] Data última revisão: 170919 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170413 [St] Status: MEDLINE [do] DOI: 10.2166/wst.2017.024

7 / 2077

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[PMID]: 28347903 [Au] Autor: Xu X; Xia L; Chen W; Huang Q [Ad] Endereço: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China; Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China. [Ti] Título: Detoxification of hexavalent chromate by growing Paecilomyces lilacinus XLA. [So] Source: Environ Pollut;225:47-54, 2017 Jun. [Is] ISSN: 1873-6424 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: In the study, the capability of Paecilomyces lilacinus XLA (CCTCC: M2012135) to reduce Cr and its main antagonistic mechanisms to Cr were experimentally evaluated. Activated growing fungus XLA efficiently reduced over 90% Cr in the media with Cr concentration below 100 mg L at pH 6 after 14 days. After 1-day exposure to 100 mg L Cr , nearly 50% of Cr was reduced. Moreover, SO stimulated Cr reduction, whereas other interferential ions inhibited Cr reduction. The interaction mechanisms between XLA and Cr mainly involve biotransformation, biosorption, and bioaccumulation, as detected by electron microscopy and chemical methods. The lower concentrations of Cr (5 and 50 mg L ) stimulated the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) level in XLA, respectively, but the higher concentration of Cr (150 mg L ) decreased the enzymatic activities and GSH concentration. The results implied that SOD, CAT and GSH were defensive guards to the oxidant stress produced by Cr . All these extracellular/intracellular defense systems endowed XLA with the ability to resist and detoxify Cr by transforming its valent species. The fungus XLA could efficiently reduce Cr under different environmental conditions (pH, interferential ions, and concentration). Moreover, XLA could endure the high concentration of Cr probably due to its high biotransformation capability of Cr and intracellular antioxidant systems for the detoxification of ROS generated by external Cr . All these results suggested that the fungus XLA can be applied to remediation of Cr -contaminated environments. [Mh] Termos MeSH primário: Biotransformação Cromatos/metabolismo Substâncias Perigosas/metabolismo Paecilomyces/metabolismo [Mh] Termos MeSH secundário: Antioxidantes/metabolismo Catalase/metabolismo Cromatos/toxicidade Glutationa/metabolismo Substâncias Perigosas/toxicidade Inativação Metabólica Superóxido Dismutase/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Antioxidants); 0 (Chromates); 0 (Hazardous Substances); EC 1.11.1.6 (Catalase); EC 1.15.1.1 (Superoxide Dismutase); GAN16C9B8O (Glutathione) [Em] Mês de entrada: 1707 [Cu] Atualização por classe: 170727 [Lr] Data última revisão: 170727 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170329 [St] Status: MEDLINE

8 / 2077

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[PMID]: 28296548 [Au] Autor: Hempelmann E; Krafts K [Ad] Endereço: a Peter Gorer Department of Immunobiology , King's College London , London , UK. [Ti] Título: The mechanism of silver staining of proteins separated by SDS polyacrylamide gel electrophoresis. [So] Source: Biotech Histochem;92(2):79-85, 2017. [Is] ISSN: 1473-7760 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: Gel based silver staining of proteins is thought to occur by selective reduction of silver ions to insoluble metallic silver at specific initiation sites in the vicinity of the protein molecules. Silver stained protein bands generally are dark brown or black with considerable variation in color intensity. The color variation has been attributed to diffractive scattering by silver grains of different sizes. Our experiments, however, demonstrate that color variation is due to the formation of silver chromate deposits that are incorporated into formalin fixed proteins. Understanding the mechanism of silver staining is essential for developing a method for protein quantification. [Mh] Termos MeSH primário: Proteínas/análise Coloração pela Prata Coloração e Rotulagem [Mh] Termos MeSH secundário: Cromatos/metabolismo Eletroforese em Gel de Poliacrilamida/métodos Formaldeído Seres Humanos Reprodutibilidade dos Testes Compostos de Prata/metabolismo [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Chromates); 0 (Proteins); 0 (Silver Compounds); 1HG84L3525 (Formaldehyde); 7784-01-2 (silver chromate) [Em] Mês de entrada: 1703 [Cu] Atualização por classe: 170330 [Lr] Data última revisão: 170330 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170316 [St] Status: MEDLINE [do] DOI: 10.1080/10520295.2016.1265149

9 / 2077

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[PMID]: 28273443 [Au] Autor: Zhong L; Lai CY; Shi LD; Wang KD; Dai YJ; Liu YW; Ma F; Rittmann BE; Zheng P; Zhao HP [Ad] Endereço: Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China. [Ti] Título: Nitrate effects on chromate reduction in a methane-based biofilm. [So] Source: Water Res;115:130-137, 2017 May 15. [Is] ISSN: 1879-2448 [Cp] País de publicação: England [La] Idioma: eng [Ab] Resumo: The effects of nitrate (NO ) on chromate (Cr(VI)) reduction in a membrane biofilm reactor (MBfR) were studied when CH was the sole electron donor supplied with a non-limiting delivery capacity. A high surface loading of NO gave significant and irreversible inhibition of Cr(VI) reduction. At a surface loading of 500 mg Cr/m -d, the Cr(VI)-removal percentage was 100% when NO was absent (Stage 1), but was dramatically lowered to < 25% with introduction of 280 mg N m -d NO (Stage 2). After ∼50 days operation in Stage 2, the Cr(VI) reduction recovered to only ∼70% in Stage 3, when NO was removed from the influent; thus, NO had a significant long-term inhibition effect on Cr(VI) reduction. Weighted PCoA and UniFrac analyses proved that the introduction of NO had a strong impact on the microbial community in the biofilms, and the changes possibly were linked to the irreversible inhibition of Cr(VI) reduction. For example, Meiothermus, the main genus involved in Cr(VI) reduction at first, declined with introduction of NO . The denitrifier Chitinophagaceae was enriched after the addition of NO , while Pelomonas became important when nitrate was removed, suggesting its potential role as a Cr(VI) reducer. Moreover, introducing NO led to a decrease in the number of genes predicted (by PICRUSt) to be related to chromate reduction, but genes predicted to be related to denitrification, methane oxidation, and fermentation increased. [Mh] Termos MeSH primário: Biofilmes Cromatos [Mh] Termos MeSH secundário: Reatores Biológicos Metano Nitratos Oxirredução [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Chromates); 0 (Nitrates); OP0UW79H66 (Methane) [Em] Mês de entrada: 1705 [Cu] Atualização por classe: 170505 [Lr] Data última revisão: 170505 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170309 [St] Status: MEDLINE

10 / 2077

MEDLINE

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[PMID]: 28254055 [Au] Autor: Singh KK; Senapati KK; Borgohain C; Sarma KC [Ad] Endereço: Department of Instrumentation and USIC, Gauhati University, Guwahati 781014, Assam, India. Electronic address: kesho.singh81@gmail.com. [Ti] Título: Newly developed Fe O -Cr O magnetic nanocomposite for photocatalytic decomposition of 4-chlorophenol in water. [So] Source: J Environ Sci (China);52:333-340, 2017 Feb. [Is] ISSN: 1001-0742 [Cp] País de publicação: Netherlands [La] Idioma: eng [Ab] Resumo: Chlorophenols, typically 4-chlorophenols are highly toxic and non-biodegradable organic contaminants which pose serious threat to the environment, particularly when released into aqueous medium. The removal of these pollutants by efficient method has received worldwide concern in recent past. A new Fe O -Cr O magnetic nanocomposite was synthesized by wet chemical method under ultrasonic irradiation. Microstructure and morphology of the nanocomposite were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and a transmission electron microscope (TEM). Magnetic and optical properties were studied by a vibrating sample magnetometer (VSM) and an ultraviolet-visible (UV-Vis) spectrophotometer respectively. The magnetic nanocomposite (MNC) was used as photocatalyst for effective decomposition of 4-chlorophenol in water under ultraviolet (UV) irradiation. [Mh] Termos MeSH primário: Clorofenóis/química Cromatos/química Compostos Férricos/química Nanocompostos/química Processos Fotoquímicos Poluentes Químicos da Água/química Purificação da Água/métodos [Mh] Termos MeSH secundário: Modelos Químicos [Pt] Tipo de publicação: JOURNAL ARTICLE [Nm] Nome de substância: 0 (Chlorophenols); 0 (Chromates); 0 (Ferric Compounds); 0 (Water Pollutants, Chemical) [Em] Mês de entrada: 1703 [Cu] Atualização por classe: 170324 [Lr] Data última revisão: 170324 [Sb] Subgrupo de revista: IM [Da] Data de entrada para processamento: 170304 [St] Status: MEDLINE

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1			PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2
2	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2
3	and or and not		PalavrasDescritor de assuntoDescritor de assunto primárioLimitesAutorPalavras do títuloPalavras do resumoIdiomaPaís de publicaçãoNome de substânciaNome de pessoa como assuntoRevistaAssunto de RevistaISSNTipo de publicaçãoIdentificador únicoMês de entradaAno de publicaçãoTexto completoAtualização por classeCategoria DeCSCategoria DeCS explodidaCategoria CID-10SubSetsPais de AfiliaçãoAfiliaçãoAfiliação 2

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