The analysis of cantharidin, a potent antitumor yet highly toxic chemical, is reported in this article. In regions including the United States, Europe, and China, cantharidin is either a banned ingredient or being highly regulated in cosmetic products. In this article, a gas chromatographic-tandem mass spectrometric (GC-MS/MS) method has been established for the determination of cantharidin in cosmetic products. Cosmetic samples were divided into two groups according to whether they contained aqueous ethanol or not. Samples containing aqueous ethanol in the formulation were dried under an air flow prior to extraction by methanol. The multiple reaction monitoring (MRM) mode with the parent ion at m/z 128 and the product ions at m/z 55 and 85 was employed. The linear range covered from 0.1 to 30.00 μg mL−1 (R = 0.9996) for cantharidin. The detection limit (LOD) was 0.3 μg kg−1. The intraday and between-day relative standard deviations (RSDs) were <8.7%. The mean recoveries were within the range 101.5–110.5%. The developed GC-MS/MS method was applied on 12 commercial cosmetic product samples, and is shown to be simple and sensitive and can be used for the qualitative and quantitative analysis of cantharidin in cosmetic products.
Triticum dicoccoides, wild emmer wheat, is the direct progenitor of cultivated wheats, has the same genome formula as durum wheat, and has contributed two genomes to bread wheat. It harbors many useful genes, more than can be used for wheat improvement. These genes are associated with many agronomic traits, abiotic stress tolerances, biotic stress resistances, grain protein content and micronutrient mineral concentrations. In this review, we summarized the achievements regarding gene discovery, i.e. gene identification, mapping and cloning in wild emmer wheat. These genes, controlling important agronomic traits, disease resistance, drought tolerance, high protein content and micronutrient mineral content, should be very useful for improvement of wheat production and food nutrition. However, the majority of genetic resources in wild emmer remain untapped, demonstrating the need for further exploration and utilization for wheat breeding programs. The large number of molecular markers, genomics tools and efficient cloning techniques available for wheat will greatly accelerate the application of wild emmer germplasm to wheat improvement and ensure sustainability of global wheat production.
Several interpolation theorems on martingale Hardy spaces over weighted measure spaces are given. Our proofs are based on
the atomic decomposition of martingale Hardy spaces over weighted measure spaces. As applications of interpolation theorems,
some inequalities of martingale transform operator are obtained.
Authors:S. Elfatih, Y. Peng, J. Ma, J. Peng, D. Sun, and W. Ma
A total of 232 accessions of tetraploid species, durum wheat (Triticum turgidum L. ssp. durum Desf., 2n=4x=28, AABB) with a widespread origin of various countries were used in this study. Their high molecular weight glutenin subunit (HMW-GS) composition was identified by Matrix-assisted laser desorption/ionization time-of-flight Mass Spectrometry (MALDI-TOF-MS). Among all accessions analyzed, 194 were homogeneous for HMW-GS, 38 were heterogeneous, and 62 possessed unusual or new subunits. The results revealed a total of 43 alleles, including 5 at Glu-A1 and 38 at Glu-B1, resulting in 60 different allele combinations. The Glu-B1 locus displayed higher variation compared with Glu-A1. Glu-A1c (55.2%) and Glu-B1aj (17.7%) were the most frequent alleles at Glu-A1 and Glu-B1, respectively. Two allele types (“null” and 1) at the Glu-A1 locus and three allele types (7OE + 8, 14+15, 8) at the Glu-B1 locus appeared to be the common types in the 232 accessions. A total of 23 new alleles represented by unusual subunits were detected at the Glu-A1 and the Glu-B1 locus.
Authors:Y. Zhang, Q. Peng, H. Zeng, S. Yao, and H. Song
A new high-performance liquid chromatography (HPLC) method has been developed and validated for determination of enantiomeric purity of thiazolidine-2-carboxylic acid within a short run time of less than 10 min. The method was based on pre-column derivatization of thiazolidine-2-carboxylic acid with aniline, and complete separation of enantiomers has been achieved on a Chiralcel OD-H analytical column (250 × 4.6 mm) using n-hexane-isopropanol (85:15 v/v) as mobile phase at a flow rate of 1.0 mL min−1 under UV and optical rotation (OR) detection. Detection wavelength was set at 254 nm. Then the effects of mobile phase and temperature on enantioselectivity were further evaluated. The method was validated with respect to precision, accuracy, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The recoveries were between 98.5 and 101.3% with percentage relative standard deviation less than 1.16%. The LOD and LOQ for the aniline derivatives of (+)-thiazolidine-2-carboxylic acid were 4.9 and 16.4 μg mL−1 and for the aniline derivatives (−)-thiazolidine-2-carboxylic acid were 5.1 and 17.2 μg mL−1, respectively.
Authors:B. Peng, P. Li, S. Lai, Y. Wang, and L. Yang
High ozone (O3) can cause great damage to plants. However, the effect of high O3 on nitrogen (N) absorption, distribution, and utilization in rice at different growth stages under different planting densities is poorly understood. In the present study, a conventional cultivar (Yangdao 6) and a hybrid cultivar (II You 084) with different planting densities were exposed to an elevated amount of O3 (E-O3; 50% higher than that of the control, C-O3) under a freeair gas concentration enrichment (FACE) system. N absorption, distribution, and utilization of the green leaves, stems, and shoots at tillering, jointing heading, and maturity were investigated. Results showed that E-O3 significantly increased the N content in the shoots of Yangdao 6 by 7.5%, 12.7%, and 19.6%, respectively, at jointing, heading, and maturity. Also, the N content in the shoots of II You 084 increased by 5.4%, 6.5%, and 8.4% at the corresponding growth stage upon E-O3 application. E-O3 significantly decreased N accumulation of II You 084 by 8.3%, 4.9%, 4.7%, and 19.2%, respectively, at tillering, jointing, heading, and maturity. Further, E-O3 had a decreasing effect on the N distribution in green leaves (p ≤ 0.05) of both cultivars, but exerted an increasing effect on that in the stems of both cultivars (p ≤ 0.05). In addition, E-O3 significantly decreased the N use efficiency (NUE) for biomass of the two cultivars in all growth stages. These results revealed that E-O3 could increase the N content in rice plants but decrease the N accumulation and utilization in both cultivars. The effects of E-O3 on N absorption, distribution, and utilization were not affected by planting density.
Authors:Ping Gong, Y. Yang, Y. Yang, Yan Feng, S. Li, Xiu Peng, and Y. Gong
New technologies in gene transfer combined with experimental embryology make the chicken embryo an excellent model system for gene function studies. The techniques of in ovo electroporation, in vitro culture for ex ovo electroporation and retrovirus-mediated gene transfer have already been fully developed in chicken. Yet to our knowledge, there are no definite descriptions on the features and application scopes of these techniques. The survival rates of different in vitro culture methods were compared and the EGFP expression areas of different gene transfer techniques were explored. It was that the optimal timings of removing embryo for EC culture and Petri dish system was at E1.5 and E2.5, respectively; and optimal timing of injecting retrovirus is at E0. Results indicated that the EC culture, in ovo electroporation, the Petri dish system and retrovirus-mediated method are, respectively, suitable for the very early, early, late and whole embryonic stages in chicken. Comparison of different gene transfer methods and establishment of optimal timings are expected to provide a better choice of the efficient method for a particular experiment.
Authors:Y. Yang, Ping Gong, Yan Feng, S. Li, Xiu Peng, Z. Ran, Y. Qian, and Y. Gong
Doublesex and mab-3-related transcription factor 1 (Dmrt1) is a Z-linked gene that putatively determines the phenotype of gonads in birds. The sex differential expression of Dmrt1 was examined using wholemount in situ hybridization (WISH) in the urogenital systems during embryogenesis. The results revealed that Dmrt1 showed dimorphic expression in chicken gonads, which increased from day 6.5 to day 10.5. The expression of Dmrt1 in male (ZZ) gonads was not twice as much as in female (ZW) gonads, suggesting the existence of other regulatory mechanisms in addition to Z chromosome dosage effect.
Authors:Y. Feng, S. Zhang, X. Peng, J. Yuan, Y. Yang, H. Zhan, and Y. Gong
In mammals, testis development is initiated by the expression of the sex-determining gene,
, where-as the genetic trigger for sex determination in birds remains unknown. In the present study, the expression of seven genes implicated in vertebrate sex determination and differentiation were studied in chicken embryonic gonads from day 4 to day 12 of incubation using reverse transcription and the polymerase chain reaction (RT-PCR). Results showed transcription of c
were sexually dimorphic during chicken gonadal development, whereas c
were expressed at similar levels in both sexes. Results of comparative studies between mammals and chickens show that vertebrate sex-determining pathways comprise both conserved and divergent elements: expression profiles of c
are similar to those in mammals, while others appear some differences. Possible functions of these genes on chicken gonadal development were analyzed based on their expression profiles.
Authors:Y. Wang, L. Yin, G. Lv, Y. Xu, L. Xu, Y. Qi, L. Zheng, and J. Peng
In the present paper, a simple and reliable high-performance liquid chromatography-diode array detection (HPLC-DAD) method was developed both for quantitative determination and fingerprint analysis of Agrimonia pilosa Ledeb for quality control. Under the optimized HPLC conditions, seven bioactive compounds including rutin, quercetin-3-rhamnoside, luteoloside, tiliroside, apigenin, kaempferol, and agrimonolide were determined simultaneously. For fingerprint analysis, 11 common peaks were selected as the characteristic peaks to evaluate the similarities of 16 different samples collected from different origins in China. Besides, hierarchical cluster analysis (HCA) was also performed to evaluate the variation of the raw materials. This is the first report of using a simple method for quality control of A. pilosa Ledeb through multi-component determination and chromatographic fingerprint analysis to the best of our knowledge.