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771.
Primary skeletal muscle cells cultured on gelatin bead microcarriers develop structural and biochemical features characteristic of adult skeletal muscle
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772.
Kafeel Ahmad Asma Ashfaq Muhammad Ashraf Nudrat Aisha Akram Sumaira Yasmin 《人类与生态风险评估》2016,22(3):597-610
Levels of Mo, As, Se, Fe, Cu, Zn, Ni, and Pb were determined in a vegetable commonly consumed in Pakistan. Samples were collected from three different sites (Ratokala, Phularwan, and Mailowal) supplied with three different water sources. Mo and Pb in water and Mo and As in C. sativum were higher than the suggested standards at the international level. Lower bioconcentration factor and pollution load index were seen at Site-I than at other sites. A positive association was found between the rhizosphere metals and those of the vegetable at all three sites. Enrichment factor at three sites ranged from 0.28 to 10.39. The highest value of daily intake of metals was found for Fe (0.245 mg/kg/day) and of the health risk index for As (70.41) at the wastewater inundated site. It is inferred that uptake of Mo, As, Cu, Ni, and Pb through C. sativum represents a high health danger to the individuals using this vegetable. 相似文献
773.
In this study, the concentrations of heavy metal (Cd, Pb, Fe, and Ni) in contaminated soils adjacent to two steel mill companies and in three crops (i.e., wheat, rice, and onion) grown in these regions were compared with a non-industrial site in Isfahan province, central Iran. The results were manifold. The heavy metal concentrations of both the soil and crops within the two industrial regions turned out to be more significant than the nonindustrial counterpart. In addition, the soils surrounding the companies were demonstrated to be contaminated by Cd, Pb, and Ni according to the limits provided by the international standards (i.e., USEPA and European Union standards). As for the crops from the investigated contaminated sites, the mean concentrations of Cd, Ni, and Pb exceeded the maximum permissible levels for human consumption stipulated by FAO/WHO standards. Furthermore, the values gained from the target hazard quotient were above one, meaning that the crops are contaminated. Given the results gained from a comparison made between estimated daily intake and tolerable daily intake, it can be concluded that the inhabitants of the two investigated contaminated sites are at a potentially serious health risk caused by exposure to the crops contaminated with the heavy metal. 相似文献
774.
Yong Yang Yang Mei Chutian Zhang Ruoxi Zhang Xiangshen Liao Yinyin Liu 《人类与生态风险评估》2016,22(1):126-140
The Qingshan district of Wuhan City is a typical Chinese industrial area. An increase in heavy metal pollution in the region's soil, due to industrialization and urbanization, has become a serious environmental problem. Surface soil samples from 155 sites were collected and analyzed. The median concentrations of cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), and zinc (Zn) in soil were 2.3, 46.2, 24.3, 28.2, and 86.8 mg/kg, respectively. Principal component analysis coupled with hierarchical cluster analysis showed that (1) in residential and industrial areas, Pb, Cu, and Zn concentrations were mainly affected by industrial emissions and traffic emissions, whereas in agricultural areas Cu and Zn were less affected by industrial emission and traffic emission, whereas Pb was affected by agricultural activities; and (2) Cd originated from a combination of sources, including industrial activities, traffic emission, and hypergene geochemical characteristics. The integrated pollution index varied from 1.1 to 16.6 with a mean of 3.9, and 70.6% of the area is extremely contaminated, 28.1% is heavily contaminated, and the remainder is moderately contaminated. 相似文献
775.
Kafeel Ahmad Zafar Iqbal Khan Sumaira Yasmin Nudrat Aisha Akram Muhammad Ashraf Asma Ashfaq 《人类与生态风险评估》2016,22(1):15-27
Accumulation of different metals and metalloids was assessed in two vegetables radish (Raphanus sativus L.) and spinach (Spinacea oleracea L.) irrigated with domestic wastewater in the peri-urban areas of Khushab City, Pakistan. In general, the metal and metalloid concentrations in radish and spinach were higher at site-II treated with sewage water than those found at site-I treated with canal water. In case of radish at both sites the levels of metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, and Pb) were below the permissible level except those of Mn, Ni, Mo, Cd, and Pb. At both sites, the transfer factor ranged from 0.047–228.3 mg kg?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: As > Fe > Ni > Zn > Cd > Mo > Se > Co > Pb > Mn > Cr > Cu, respectively. While in case of spinach at both sites, the concentrations of metals and metalloids in vegetable samples irrigated with canal and sewage water were observed below the permissible level except Mn, Ni, Zn, Mo, and Pb. At both sites, the transfer factor ranged from 0.038–245.4 mg kg?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: Cd > Ni > Co > Se > Mn > Zn > Mo > Pb > Fe > Cr > As > Cu, respectively. 相似文献
776.
Health risk assessment of heavy metals in groundwater of coal mining area: A case study in Dingji coal mine,Huainan coalfield,China 总被引:1,自引:0,他引:1
Heavy metals enrichment in groundwater poses great ecological risks to human beings. In the present research work, a total of 59 groundwater samples from 12 sampling points in Dingji coal mine, Huainan coalfield, were collected and measured for Cu, Pb, Zn, Cd, Ni, Mn, Cr, and Fe by inductively coupled plasma mass spectrometry (ICP-MS). The human health risk caused by heavy metals through the pathway of drinking water was evaluated and analyzed using the US Environment Protection Agency (USEPA) evaluation model. It has been found that the carcinogenic risk values were between 1.05 × 10?5 and 3.5 × 10?4, all exceeding the maximum acceptable level recommended by the USEPA, and the carcinogenic risk of Cr accounted for 99.67% of the total carcinogenic risk. The non-carcinogenic health risk values were all lower than the negligible level given by the USEPA, and the contribution of non-carcinogenic health risk was in the order of Cr > Zn > Cu / Pb >Mn > Fe > Cd > Ni. Among them, Cr had the largest contribution, accounting for 36% of the total non-carcinogenic risk value. In this study, the carcinogenic risk constituted 99.99% of the total health risk, indicating that the total health risk essentially consisted of carcinogenic risk. The research results suggest that much more attention should be paid to the health risk caused by Cr in the groundwater. 相似文献
777.
Somsak Intamat Uraiwan Phoonaploy Manop Sriuttha Bundit Tengjaroenkul 《人类与生态风险评估》2016,22(6):1418-1432
This research was conducted to assess the water quality and the contamination of heavy metals in water, sediment, fish, and frogs, as well as bioaccumulation factors (BAFs) in fish and frogs around the gold mine area. The water samples were analyzed for water quality (temperature, pH, and dissolved oxygen). The samples were analyzed for heavy metals by inductively coupled plasma optical emission spectrometry. The water quality was within the standard. The concentrations of heavy metals, including As, Cr, Cd, Pb, Ni, Zn, Fe, Mn, and Cu, in water and sediment samples were measured. Three species of fish were collected: Rasbora tornieri, Brachydanio albolineata, and Systomus rubripinnis. The mean heavy metal concentrations of fish were as follows: Fe>Zn>Mn>Cr>Ni>Cu>As>Pb>Cd. The As, Cr, and Pb concentrations in all the fish species exceeded the standard levels. Five species of frogs were collected: Kaloula pulchra, Microhyla heymonsi, Fejervarya limnocharis, Hoplobatrachus rugulosus, and Microhyla pulchra. The mean heavy metal concentrations of frog were as follows: Fe>Cu>Mn>Zn>Cr>Ni>Pb>Cd>As. The Cr, Cd, and Cu concentrations exceeded the standard levels. The BAFs in fish were in order of Cr>Zn>Ni>Cu>Pb>Fe>Cd>As. The BAFs in frogs were Cr>Zn>Ni>Cu>Fe>Pb>Cd>As. The accumulation of heavy metals was higher in the sediment than in the water. Many aquatic organisms take up heavy metals directly from the environment around the gold mine. 相似文献
778.
Gloria Lozano Reyes Jimenez-Aparicio Santiago Herrero Encarnacion Martinez-Salas 《RNA (New York, N.Y.)》2016,22(3):330-338
RNA function is determined by its structural organization. The RNA structure consists of the combination of distinct secondary structure motifs connected by junctions that play an essential role in RNA folding. Selective 2′-hydroxyl acylation analyzed by primer extension (SHAPE) probing is an established methodology to analyze the secondary structure of long RNA molecules in solution, which provides accurate data about unpaired nucleotides. However, the residues located at the junctions of RNA structures usually remain undetected. Here we report an RNA probing method based on the use of a novel open-paddlewheel diruthenium (OPW-Ru) compound [Ru2Cl2(µ-DPhF)3(DMSO)] (DPhF = N,N′-diphenylformamidinate). This compound has four potential coordination sites in a singular disposition to establish covalent bonds with substrates. As a proof of concept, we have analyzed the reactivity of OPW-Ru toward RNA using two viral internal ribosome entry site (IRES) elements whose function depends on the structural organization of the molecule. Our study suggests that the compound OPW-Ru preferentially attacks at positions located one or two nucleotides away from junctions or bulges of the RNA structure. The OPW-Ru fingerprinting data differ from that obtained by other chemical reagents and provides new information about RNA structure features. 相似文献
779.
Antimicrobial susceptibility monitoring of dermatological bacterial pathogens isolated from diseased dogs and cats across Europe (ComPath results)
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C. Ludwig A. de Jong H. Moyaert F. El Garch R. Janes U. Klein I. Morrissey J. Thiry M. Youala 《Journal of applied microbiology》2016,121(5):1254-1267
780.
Puig S Mira H Dorcey E Sancenón V Andrés-Colás N Garcia-Molina A Burkhead JL Gogolin KA Abdel-Ghany SE Thiele DJ Ecker JR Pilon M Peñarrubia L 《Biochemical and biophysical research communications》2007,354(2):385-390
Copper (Cu) chaperones constitute a family of small Cu+-binding proteins required for Cu homeostasis in eukaryotes. The ATX1 family of Cu chaperones specifically delivers Cu to heavy metal P-type ATPases. The plant Arabidopsis thaliana expresses the ATX1-like Cu chaperone CCH, which exhibits a plant-specific carboxy-terminal domain (CTD) with unique structural properties. We show that CCH homologues from other higher plants contain CTDs with structural properties similar to Arabidopsis CCH. Furthermore, we identify a new ATX1-like Cu chaperone in Arabidopsis, AtATX1, which functionally complements yeast atx1Delta and sod1Delta associated phenotypes, and localizes to the cytosol of Arabidopsis cells. Interestingly, AtATX1, but not full-length CCH, interacts in vivo with the Arabidopsis RAN1 Cu-transporting P-type ATPase by yeast two-hybrid. We propose that higher plants express two types of ATX1-like Cu chaperones: the ATX1-type with a predominant function in Cu delivery to P-type ATPases, and the CCH-type with additional CTD-mediated plant-specific functions. 相似文献