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Abstract  

The preparation of a cold kit was introduced in the paper, and the effective quantities of the components (Vc, HEDP and SnCl2·2H2O) in the kit were determined. At the sametime, the effects of labelling kit on the reaction time, reaction temperature and animal distribution were studied in detail. The initial animal experiment showed the high uptake in the skeletal tissue, the clearance in the blood was quick.

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Abstract  

Two procedures are described for fast separations of berkelium from complex mixtures of reaction products arising from heavy ion reactions, such as18O+248Cm. The first procedure uses a combination of several extraction steps with a final separation on a cation exchanger, the second procedure starts with an anion exchange column which is followed by multiple extractions in different media. The elements separated in the different steps were analyzed and overall decontamination factors are given.

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Abstract

Bis(1-octylammonium) tetrachlorocuprate (1-C8H17NH3)2CuCl4(s) was synthesized by the method of liquid phase reaction. The crystal structure of the compound has been determined by X-ray crystallography. The lattice potential energy was obtained from the crystallographic data. Molar enthalpies of dissolution of (1-C8H17NH3)2CuCl4(s) at various molalities were measured at 298.15 K in the double-distilled water by means of an isoperibol solution-reaction calorimeter, respectively. In terms of Pitzer's electrolyte solution theory, the molar enthalpy of dissolution of (1-C8H17NH3)2CuCl4(s) at infinite dilution was determined to be and the sums of Pitzer's parameters and were obtained.

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Abstract  

Thermogravimetry (TG) was employed to study the thermal degradation kinetics of poly(etherketone/sulfone)ethylimide (PEK-IE and PES-IE). The corresponding decomposition activation energies and reaction orders were obtained and the comparison was made with their parent polymerspoly(ether-ketone/sulfone) with Cardo group (PEK-C and PES-C). The results show that the degradation activation energies of PEK-IE and PES-IE were lower than that of PEK-C and PES-C; and two stages of the degradation process were found for all the four polymers. For PEK-IE and PES-IE, the activation energies in the first decomposition stage are much lower than that in the second stage and the two stages can be taken as slow induction and fast degradation, whereas for PEK-C and PES-C the activation energies in the first decomposition stage are larger than that in the second stage, and the two stages can both be taken as two fast degradation stages. The decomposition mechanism of the two stages was also speculated.

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Abstract  

Occupational exposure to Cr(VI) causes various effects including deep skin ulcerations. Its action mechanisms are not fully understood. In the present study, the evaluation of human dermal fibroblasts heat production was monitored, using microcalorimetry. as part of Cr(VI) toxicity. In control cells, normal heat production was 15±5 pW/cell. Regardless of the Cr(VI) concentration tested (0 to 500 μM), heat production was inhibited over time periods ranging from 3 to 25 h. These results could be correlated with cell mortality and the IC50 for Cr(VI) was 29±4 μM. In the WST-1 bioassay, the IC50 was 35±5 μM (no statistical difference). Thus, Cr(VI) altered the metabolism of the fibroblasts, and led to cellular death. Microcalorimetry can be a useful tool for determining the toxic effect of suspect compounds implicated in the occurrence of pathologies.

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Summary

Rapid high-performance liquid chromatographic methods with evaporative light scattering detection (HPLC-ELSD) and electrospray ionization multistage mass spectrometry (HPLC-ESI-MSn) have been established and validated for simultaneous qualitative and quantitative analysis of eight steroidal saponins in ten batches of Gongxuening capsule (GXN), a widely commercially available traditional Chinese preparation. The optimum chromatographic conditions entailed use of a Kromasil C18 column with acetonitrile-water (30:70 to 62:38, υ/υ) as mobile phase at a flow rate of 1.0 mL min−1. The drift tube temperature of the ELSD was 102°C and the nebulizing gas flow rate was 2.8 L min−1. Separation was successfully achieved within 25 min. LC-ESI-MSn was used for unequivocal identification of the constituents of the samples by comparison with reference compounds. The assay was fully validated for precision, repeatability, accuracy, and stability, then successfully applied to quantification of the eight compounds in samples. The method could be effective for evaluation of the clinical safety and efficacy of GXN.

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Summary

Radix Isatidis has widely useful activities including anti-virus, anti-bacterial. Tryptanthrin, indigo, and indirubin are active ingredients in R. Isatidis. Response surface methodology (RSM)-optimized infrared-assisted extraction (IRAE) was developed and combined with HPLC for simultaneous determination of tryptanthrin, indigo, and indirubin from R. Isatidis. IRAE were investigated through extraction yields of the three components and optimized by RSM. The optimum conditions were as follows: infrared power of 129 W, solid/liquid ratio of 1:40 g/mL, and irradiation time of 22.5 min. IRAE conditions obtained by RSM were not only accurate, but also had practical value reflecting the expected optimization. Subsequently, this novel IRAE method was evaluated by extraction yield of the components of R. Isatidis samples from different regions. Compared with common extraction methods including maceration extraction (ME), reflux extraction (RE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE), IRAE showed higher yield with advantages of no limitation of solvent selection, low cost, convenience under optimum extraction conditions. These results suggested the potential of RSM-optimized IRAE for extraction and analysis of the water-/fat-soluble compositions of Chinese herbal medicine. A simple chromatographic separation for simultaneous determination of tryptanthrin, indigo, and indirubin from Chinese herbal medicine R. Isatidis was performed on a C18 column (Diamonsil 150 mm × 4.6 mm i.d., 5 μm) with a mobile phase isocratic consisting of methanol and water at a flow-rate of 0.8 mL min−1. The retention times of tryptanthrin, indigo, and indirubin were 15.4, 31.9, and 58.6 min, respectively. The linear equations were obtained as follows: y = −3094.5744 + 21208.792x for tryptanthrin (R = 0.9998, 0.9–18.0 μg mL−1), y = 4730.0448 + 30180.567x for indigo (R = 0.9997, 0.5–10.0 μg mL−1) and y = −6582.9045 + 67069.312x for indirubin (R = 0.9997, 0.4–8.0 μg mL−1). The result showed that RSM-optimized IRAE was a simple, efficient pretreatment method for the analysis of complex matrix.

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Aegilops tauschii is the generally accepted D genome diploid donor of hexaploid wheat. The significance of Ae. tauschii HMW-GS genes on bread-making properties of bread wheat has been well documented. Among them, Ae. tauschii HMW-GS Dx5 t +Dy12 t was thought as the pair with potentially value in endowing synthetic hexaploid wheat with good end-use qualities. In this paper, we isolated and sequenced genes Dx5 t and Dy12 t from Ae. tauschii accession As63. Amino acid sequence comparison indicated that Dy12 t from Ae. tauschii is more similar to Dy10 rather than Dy12 of bread wheat. The sequence of Dx5 t in Ae. tauschii accession As63 showed higher similarity to that of Dx5 in bread wheat than others. However, it is notable that Dx5 t lacked the additional cysteine residue in Dx5, which is responsible for good bread-making quality in common wheat. Moreover, compared to Dx5, Dx5 t has an extra hexpeptide repetitive motif unit (SGQGQQ) as well as five amino acid substitutions.

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Cereal Research Communications
Authors: L. Zhang, Z. Yan, S. Dai, Q. Chen, Z. Yuan, Y. Zheng, and D. Liu

Two experiments to investigate the crossability of Triticum turgidum with Aegilops tauschii are described. In the first experiment, 372 wide hybridization combinations were done by crossing 196 T. turgidum lines belonging to seven subspecies with 13 Ae. tauschii accessions. Without embryo rescue and hormone treatment, from the 66220 florets pollinated, 3713 seeds were obtained, with a mean crossability percentages of 5.61% which ranged from 0 to 75%. A lot of hybrid seeds could germinate and produce plants. Out of 372 combinations, 73.12% showed a very low crossability less than 5%, 23.39% showed the crossability of 5–30%, 2.69% showed the crossability of 30–50%, 0.81% showed high crossability more than 50%, respectively. Among the seven T. turgidum subspecies, there were significant differences in crossability. The ssp. dicoccoides and dicoccon showed the highest crossability, while polonicum the lowest. All the crossability percentages more than 30% were obtained from the crossing of ssp. dicoccoides or dicoccon with Ae. tauschii .In the second experiment, the genetics of crossability was investigated using T. turgidum ssp. durum cultivar Langdon and the D-genome disomic substitution lines of Langdon. Compared with the control Langdon, lines 7D(7A) and 4D(4B) showed higher crossability, which suggested that chromosomes 7A and 4B of tetraploid wheat cv. Langdon carried dominant alleles inhibiting crossability with Ae. tauschii . The relationships of present results with previously reported crossability genes of wheat are discussed.

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Cereal Research Communications
Authors: Z. L. Li, D. D. Wu, H. Y. Li, G. Chen, W. G. Cao, S. Z. Ning, D. C. Liu, and L. Q. Zhang

Gliadin is a main component of gluten proteins that affect functional properties of bread making and contributes to the viscous nature of doughs. In this study, thirteen novel ω-gliadin genes were identified in several Triticum species, which encode the ARH-, ATDand ATN-type proteins. Two novel types of ω-gliadins: ATD- and ATN- have not yet been reported. The lengths of 13 sequences were ranged from 927 to 1269 bp and the deduced mature proteins were varied from 309 to 414 residues. All 13 genes were pseudogenes because of the presence of internal stop codons. The primary structure of these ω-gliadin genes included a signal peptide, a conserved N-terminal domain, a repetitive domain and a conserved C-terminus. In this paper, we first characterize ω-gliadin genes from T. timopheevi ssp. timopheevi and T. timopheevi ssp. araraticum. The ω-gliadin gene variation and the evolutionary relationship of ω-gliadin family genes were also discussed.

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