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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Gu-Cai Li
,
Duan-Zhi Yin
,
Deng-Feng Cheng
,
Ming-Qiang Zheng
,
Yan-Jiang Han
,
Han-Chen Cai
,
Jiao-Yun Xia
,
Sheng Liang
,
Wan-Bang Xu
, and
Yong-Xian Wang

Abstract  

3-(4-[18F]fluorobenzyl)-8-hydroxy-1,2,3,4-tetrahydrochromeno[3,4-c]pyridin-5-one ([18F]FHTP) was in vitro and in vivo evaluated as a putative dopamine D4 receptor radioligand. Its inhibition constant (K i ) for cloned human dopamine D4.2 receptor was determined to be 2.9 nM and it displayed a 2000-fold D4-selectivity over the D2long subtype. Its partition coefficient (logP) was measured to be 1.11. Biodistribution, blocking distribution and metabolism studies in rats demonstrated that the specific distribution of [18F]FHTP in brain regions, suggesting that [18F]FHTP may be a suitable PET imaging agent for in vivo studies of the dopamine D4 receptor.

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To explore the physiological characteristics of the pepc gene in transgenic wheat (Triticum aestivum) plants, PEPC activities in various organs of T3 plants were analyzed at Feekes 6.0, Feekes 10.3 and Feekes 11.1, and compared to control, untransformed wheat cultivar Zhoumai 19. Net photosynthetic rates (P n) in leaves were also measured at the same stages. At Feekes 11.1, both transgenic and control plants were treated with DCDP. Yield traits were surveyed after harvest. The results indicated that P n and PEPC activity in the flag leaf of transgenic wheat were significantly higher than those of the control at different stages. At Feekes 10.3, P n reached the highest value at 28.2 μmol m−2 s−1 and PEPC activity reached the highest value at 104.6 μmol h−1 mg−1. Both factors significantly increased by 21% compared to the control at Feekes 11.1. PEPC activity in the flag leaf of transgenic plants was significantly higher than that of non-leaf organs. P n of transgenic plants was greatly reduced after DCDP treatment. In the flag leaf of transgenic wheat, P n was significantly correlated to PEPC activities at 0.01 probability level with a correlation coefficient of 0.8957**. The yield traits of transgenic line 1-27-3, such as 1000-grain weight, single spike weight and harvest index were higher than those of the control. Additionally, the spike weight of 1-27-3 showed an increase of approximately 9.5% compared to the control. These results indicated that the expression of maize (Zea mays) pepc gene was different across various organs of transgenic wheat and across every growth stage. Therefore, we conclude that introducing maize pepc gene into wheat plants can increase their P n and improve production.

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Abstract

Atractylodis macrocephalae rhizome (AMR) belongs to medicine food homology. Its' clinical application of invigorating the spleen-stomach of AMR was applied to various diseases. In this research, a UPLC-QTOF-MS method was developed for qualitative and quantitative analysis of AMR, simultaneously. A Waters Acquity BEH C18 column (2.1 mm × 100 mm, 1.7 μm particle size) was used for separation of AMR multi-components. The column was eluted with a mobile phase of 0.1% formic acid-water and 0.1% formic acid-acetonitrile. Electron spray ionization with positive-ion mode and external standard method was utilized for quantifying the nine analytes in AMR. Constituents of AMR were scanned by UPLC-QTOF-MS and then identified by mass fragments and chromatographic information compared with the published literature and reference standards. Under positive mode, a total of 61 chemical compositions including 16 terpenoids, 8 polyacetylenes, 6 aromatics, 5 flavonoids, 5 coumarins, 5 organic acids, 4 amino acids, 3 fatty acids, 3 aliphatics, 2 steroids, and 2 alkenes, a nucleoside and an aldehyde were identified. Simultaneously, the contents of three amino acids (L-tyrosine, L-phenylalanine, and L-tryptophan), three sesquiterpenoids (atractylenolide Ⅲ, atractylenolide Ⅱ, and atractylenolide Ⅰ), a flavonoid (rutin), an organic acid (ferulic acid), and a pentacyclic triterpenoid (oleanolic acid) were determined in seventeen AMR batches. Amino acids and triterpenoid were quantified for the first time in AMR. The UPLC-QTOF-MS method developed in this article was reliable, practical, and useful for qualitative and quantitative evaluation of AMR multi-components.

Open access
Journal of Thermal Analysis and Calorimetry
Authors:
Li-Fang Song
,
Chun-Hong Jiang
,
Jian Zhang
,
Li-Xian Sun
,
Fen Xu
,
Wan-Sheng You
,
Yi Zhao
,
Zhi-Heng Zhang
,
Mei-Han Wang
,
Yutake Sawada
,
Zhong Cao
, and
Ju-Lan Zeng

Abstract  

A novel metal-organic frameworks [Cu2(OH)(2,2′-bpy)2(BTC) · 2H2O]n (CuMOF, BTC = benzene-1,3,5-tricarboxylic acid, 2,2′-bpy = 2,2′-bipyridine) has been synthesized hydrothermally and characterized by single crystal XRD, FT-IR spectra. The low-temperature molar heat capacities were measured by temperature modulated differential scanning calorimetry (TMDSC) for the first time. The thermodynamic parameters such as entropy and enthalpy relative to reference temperature 298.15 K were derived based on the above molar heat capacity data. Moreover, the thermal stability and the decomposition mechanism of CuMOF were investigated by TG-MS (thermogravimetry-mass spectrometer). A four-stage mass loss was observed in the TG curve. MS curve indicated that the gas products for oxidative degradation of CuMOF were H2O, CO2, NO and NO2.

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Acta Biologica Hungarica
Authors:
Xiang-Rong Xu
,
Fu-Qing Tan
,
Jun-Quan Zhu
,
Ting Ye
,
Chun-Lin Wang
,
Yi-Feng Zhu
,
Hans-Uwe Dahms
,
Fan Jin
, and
Wan-Xi Yang

We used single-cell gel electrophoresis (SCGE) to detect the integrity of sperm DNA of the teleost large yellow croaker, Pseudosciaena crocea, cryopreserved with Cortland solution and a range of 5% to 30% DMSO concentrations in order to test how sperm cryopreservation affected the DNA stability of nuclei. Electrophoresis was conducted for 60 min at 130 mA and 15 V. The comet images were analyzed with software CometScore 1.5, and parameters such as comet length, tail length and percentage DNA in the tail were obtained. Then the comet rate and damage coefficient were calculated. Results demonstrated that there were no significant differences in motility, comet rate and damage coefficient between fresh sperm and cryopreserved sperm stored in 5%, 10%, 15% and 20% DMSO, while the sperm cryopreserved with 25% and 30% DMSO had a lower motility, higher comet length and damage coefficients than those of fresh sperm. There was a positive correlation between comet rate of cryopreserved sperm and the concentration of DMSO. Our results demonstrate that toxicity of the cryoprotectant is the main cause of DNA damage in cryopreserved sperm nuclei.

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Acta Chromatographica
Authors:
Xiuhui Tian
,
Dianfeng Han
,
Yanmei Cui
,
Lihua Ren
,
Fang Jiang
,
Hui Huang
,
Xianghong Gong
,
Jinglin Xue
,
Jiawei Li
,
Huihui Liu
,
Yingjiang Xu
,
Xiaojun Luo
,
Xiaojing Liu
, and
Xiuzhen Zhang

Abstract

A sensitive and validated method for determining quinocetone and its main metabolites (3-methylquinoxaline-2-carboxylic acid and dedioxoquinenone) was established in aquatic products using ultra-high-performance liquid chromatography-tandem spectrometry (UHPLC-MS/MS). Samples were extracted with 2.0 mol L−1 hydrochloric acid, then purified on MAX columns. After extraction and purification, the supernatant was evaporated to dry nearly under a gentle stream of nitrogen at 40 °C. Formic acid-acetonitrile-water (0.1/30/70, v/v/v) was adjusted to 1.00 mL final volume. An aliquot (10 μL) was injected into the C18 column for separation with the mobile phase of acetonitrile and 0.5% formic acid in water at 0.25 mL min−1. Calibration curves were linear ranged from 10.00 ng mL−1 to 200.0 ng mL−1 for quinocetone and 3-methylquinoxaline-2-carboxylic acid, and 20.00 ng mL−1 to 400.0 ng mL−1 for dedioxoquinenone. Mean recoveries were 70%–89%, 73%–83% and 72%–84%, respectively. The limit of detection (LOD) was 1.00 μg kg−1, 1.00 μg kg−1 and 2.00 μg kg−1, and quantification (LOQ) were 2.00 μg kg−1, 2.00 μg kg−1 and 4.00 μg kg−1 for quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone. Based on the method above, the analytes were determined in Apostichopus japonicus, three fishes (including Ctenopharyngodon idellus, Crucian carp and Oreochromis mossambicus), Penaeus vannamei, Penaeus chinensis, and Chlamys farreri. The method shows good sensitivity, linearity, precision, and accuracy. In short, the proposed method was reliable for the determination of quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone in aquatic products.

Open access

Abstract

Background and aims

Problematic use of the internet (PUI) among adolescents has become one of the public problems around the world. Understanding the developmental trajectory of PUI may be beneficial to develop prevention and intervention. The current study aimed to identify the developmental trajectories of PUI among adolescents, considering individual differences over time. And also explored how familial factors contributed to the identified trajectories, and the relationship between PUI changes over time and social, mental health, and academic functioning.

Methods

A total of 1,149 adolescents (Mage  = 15.82, SD = 0.61; 55.27% girls at Wave 1) participated in assessments at four time points, using 6-month assessment intervals.

Results

Based on a latent class growth model, three trajectories of PUI were identified: Low Decreasing, Moderate Increasing, and High Increasing groups. Multivariate logistic regression analyses suggested that inter-parental conflicts and childhood maltreatment served as negative familial predictors for the risk trajectories of PUI (i.e., Moderate Increasing and High Increasing groups). Additionally, adolescents in these two groups displayed more estranged interpersonal relationships, more mental health difficulties, and poorer academic functioning.

Discussion and conclusions

It is important to consider individual differences in understanding the developmental patterns of PUI among adolescents. Identifying family predictors and the behavioral outcome associated with groups with different developmental trajectories of PUI, which may help to understand better risk factors related to specific developmental patterns of PUI and its adverse correlates. The findings highlight a need to develop more specific effective intervention programs for individuals displaying different problematic developmental trajectories with PUI.

Open access