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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Y. Xu
,
W. Yang
,
S. Yuan
,
Y. Xiao
,
X. Zhou
, and
J. He

Abstract  

Osmium isotope, 197Os, produced with 14 MeV neutrons through the reaction of 198Pt(n,2p)197Os, has been identified and its decay properties have been studied with a g(X) spectroscopic method. The ten new g-rays of 41.2, 50.7, 196.8, 199.6, 223.9, 233.1, 250.2, 342.1, 403.6, and 406.4 keV assigned to the decay of 197Os were observed. The half-life of 197Os has been determined as 2.8±0.6 minutes. A partial decay scheme of 197Os was proposed.

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Abstract  

Although Ir anomaly has been discovered in a number of C/T boundaries in the world, no positive results of this anomaly in Permian/Triassic (P/Tr) boundary were given. There are many well-developed P/T sections in South China. One of representative sections is located at the Baoqing quarry, Meishan Town, Changxin County, Zhejiang Province. Ir, Os, Re, Au, Pt, Cu and Mo were determined by the radiochemical procedure developed in our laboratory. (1) Besides those accessible by INAA. The results reveal that the refractory siderophile and other chalcophile elements have certain enrichment near and at the boundary layer. However, the Ir/Au and other element abundance ratios fail to accord with the extraterrestrial values. The nature of the boundary event was discussed in terms of elemental geochemistry.

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Abstract  

The concentrations of 14 elements, including Ir, Au, Co, Cr, Fe, Sr, Rb, K, Ta, Zn, Sb, Ba, Sc and Se, in the Wuxi fallen ice were determined by neutron activation analysis. The experimental results show that the relative concentration ratios of Ir/Co, Ir/Cr and Ir/Sc etc. in the ice water (0.0069, 0.00024 and 0.11, respectively) are quite close to those of Type C1 chondrite (0.0102, 0.00021 and 0.092, respectively), which implies that the fallen ice might be a piece of extraterrestrial substance.

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In mammals, testis development is initiated by the expression of the sex-determining gene, SRY , 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 Lhx9 , c GATA4 , c Vnn1 , c Ppt1 , c Brd3 were sexually dimorphic during chicken gonadal development, whereas c Eki2 , c Fog2 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 GATA4 /c Fog2 and c Vnn1 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.

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The aim of the present study was to investigate whether co-administration of nerve growth factor (NGF) and butyrate regulates vanilloid receptor 1 (VR1) and substance P (SP) levels in cultures of rat dorsal root ganglion (DRG) neurons. DRG was dissected out from embryonic 15-day-old Wistar rat and cultured as dissociated cells for 2 days then exposed to NGF (10 ng/ml), butyrate (1 mmol/L), NGF (10 ng/ml) plus butyrate (1 mmol/L) for another 4 days. The neurons cultured continuously in media served as normal control. After that, the cultures were processed for detecting expression of mRNA for VR1 and SP in DRG neurons by RT-PCR, and expression of VR1 protein by Western blot. SP basal release levels were measured by radioimmunoassay (RIA). Capsaicin-evoked SP release was measured by RIA after stimulation with capsaicin (100 nmol/L) for 10 minutes. The neurons exposed to vehicle solution served as vehicle control. Either NGF (10 ng/ml) or butyrate (1 mmol/L) promoted expression of SP mRNA, VR1 mRNA, and VR1 protein in DRG neurons and capsaicin-evoked SP release from DRG neurons. Co-administration of NGF and butyrate showed a synergistic effect on expression of VR1 mRNA, and VR1 protein in DRG neurons and capsaicin-evoked SP release from DRG neurons and a ceiling effect on SP mRNA expression. The elevation of SP mRNA, VR1 mRNA, and VR1 protein promoted by NGF and/or butyrate may be associated with increases of SP release evoked by capsaicin. The mechanisms of the effects of co-administration of NGF and butyrate should be clarified by further study.

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Summary

The chemical compositions of essential oils extracted by n-hexane extract (HE), petroleum ether extract (PE), dichloromethane extract (DE), and hydrodistillation (HD) from Carthamus tinctorius L. (safflower) were analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 86 compounds from four different extracts were identified, and the contents were 97.65%, 98.05%, 98.93%, and 99.68%, respectively. 6,10,14-Trimethyl-2-pentadecanone, hexadecanoic acid, methyl ester, hexadecanoic acid, 8,11-octadecadienoic acid, methyl ester, and 9,12,15-octadecatrien-1-ol were the major constituents of the extracts. The antidiabete activity was assayed in vitro by against protein tyrosine phosphatase 1B (PTP1B). The results showed that the HE exhibited the best in vitro inhibitory enzyme activity against PTP1B, which holds a good potential for treating diabetes and obesity.

Open access

Summary

Silica-gel column chromatography and preparative reversed-phase high-performance liquid chromatography (RP-HPLC) were sequentially employed for the isolation of two antioxidants including gallic acid and methyl gallate from Folium Toonea Sinensis. An RP-HPLC-UV method was then developed and validated to rapidly determine their content in this herb with ethyl gallate as internal standard. The quantitation was performed on an XBridge Shield RP18 column (150 mm × 4.6 mm, 5 μm) under 40°C. The mobile phase consisting of acetonitrile and 0.1% formic acid aqueous solution was driven at 1.0 mL min−1 under gradient elution, and 270 nm was selected to monitor the separation. To evaluate the fitness for purpose of the method and to investigate the difference in the content of analytes among different samples, the leaves collected from five production sites were analyzed. The newly established method is suitable for routine analysis of gallic acid and methyl gallate in the herb and, hence, can assist in its quality assessment. It was also found that not only the content of two antioxidants but also the ratio varied significantly among different geographical origins. In addition, three samples from Yantai, Zumadian, and Zhenjiang were distinguished as they have a much higher content ratio than the other two.

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Traditional Chinese medicine (TCM) has been widely used in many countries for thousands of years and played an indispensable role in the prevention and treatment of diseases, especially the complicated and chronic ones. However, the application of TCM in diseases is still not fully recognized by people around the world, the main reason is that Chinese herb is a very complex mixture containing hundreds of different components. Thus, it is essential to make quality control and evaluation of TCM. A new quality evaluation method, quantitative analysis of multi-components by single marker (QAMS), was developed to the quality control of alkaloids in TCM, a case study on Radix aconiti lateralis, named Fuzi in Chinese. Six alkaloids, including aconitine, hypaconitine, mesaconitine, benzoylaconine, benzoylmesaconine, and benzoylhypaconine, were selected as main components to evaluate the quality of Radix aconiti lateralis. The feasibility and accuracy of QAMS were checked by the external standard method, and various high-performance liquid chromatographic instruments and chromatographic conditions were investigated to verify its applicability. Using aconitine as the internal reference substance and the content of aconitine was calculated according to relative correction factors by high-performance liquid chromatography. The present results showed that there was no significant difference observed between the QAMS method and the external standard method with the relative average deviations less than 3.0%, and QAMS is an effective way to control the quality of herbal medicines and seems to be a convenient and accurate approach to analyze multi-composition when reference substances are unavailable.

Open access

Summary

10-O-(N,N-dimethylaminoethyl)-ginkgolide B (XQ-1) is an intermediate for synthesizing 10-O-(N,N-dimethylaminoethyl)-ginkgolide B methanesulfonate (XQ-1H), which is a novel ginkgolide B derivative and is being developed as a platelet-activating factor antagonist. A specific and rapid liquid chromatographic method was developed for the quantitative analysis of XQ-1 and its three related impurities, which were 10-O-(N,N-dimethylaminoethyl)-11,12-seco-ginkgolide B (imp-1), 10-O-(N,N-dimethylaminoethyl)-11,12-seco-3,14-dehydroginkgolide B (imp-2) and 10-O-(N,N-dimethylaminoethyl)-3,14-dehydroginkgolide B (imp-3) simultaneously in XQ-1 samples. Chromatographic separation was achieved on a CN band stationary phase, with the mobile phase consisting of methanol and 20 mM dipotassium hydrogen phosphate (pH 7.5) (50:50, υ/υ) in isocratic elution. The flow rate was 1.0 mL min−1 and detector was set at 220 nm. The method was optimized by the analysis of the samples generated during the forced degradation studies. The XQ-1, imp-1, imp-2, and imp-3 were completely separated within 15 min. The resolutions (R s) amongst four target compounds were >2. The developed method was validated with respect to specificity, linearity, accuracy, precision, and robustness. The results indicated that the simultaneous LC determination method was readily utilized as a quality control method for XQ-1 sample.

Open access

Uniformity in the height of main stem and tillers is a key factor affecting ideal plant type, a key component in super high-yielding rice breeding. An understanding of the genetic basis of the panicle layer uniformity may thus contribute to breeding varieties with good plant type and high yield. In the present study, a doubled haploid (DH) population, derived from a cross between indica rice variety Zhai-Ye-Qing 8 (ZYQ8) and japonica rice variety Jing-Xi 17 (JX17) was used to analyze quantitative trait loci (QTL) for panicle layer uniformity related traits. Six, four and three QTL were detected for the highest panicle height (HPH), lowest panicle height (LPH) and panicle layer dis-uniformity (PLD), respectively. qHPH-1-1 and qPLD-1 were located at the same interval on chromosome 1. The JX17 allele(s) of these QTL increased HPH and PLD by 2.57 and 1.26 cm, respectively. Similarly, qPLD-7 and qHPH-7 were located at the same interval on chromosome 7, where the ZYQ8 allele(s) increased HPH and PLD by 3.74 and 1.96 cm, respectively. These four QTL were unfavourable for panicle layer uniformity improvement because a decrease of the PLD was accompanied by decrease of the plant height. qPLD-6 and qLPH-6-1 were located at the same interval on chromosome 6, however here the JX17 allele(s) increased LPH, but decreased PLD, suggesting that this QTL was favourable for improvement of panicle layer uniformity. The markers identified in this study are potential for marker assisted breeding for the improvement of the panicle layer uniformity and ideal plant type.

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