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Acta Chromatographica
Authors: Long Wang, Yuan-Yuan Jiang, Li Zhang, Tao Wang, Rui-Wu Yang, Chun-Bang Ding, Xiao-Li Wang, and Yong-Hong Zhou

A high-performance liquid chromatography (HPLC) method has been developed for the simultaneous identification and quantification of active compounds (cryptotanshinone, dihydrotanshinone I, tanshinone IIA, tanshinone I, salvianolic acid A, salvianolic acid B, protocatechuic aldehyde, and rosmarinic acid) contained in traditional Chinese folk medicine Salvia przewalskii Maxim. The herb samples (including wild, cultivated, and yin pian) from fourteen main regions were investigated. Chromatographic separation was performed on an Agilent Eclipse XDB-C18 reserved-phase column (250 mm × 4.6 mm i.d., 5 μm) using gradient elution with water-formic acid (99.9: 0.1, v/v) and acetonitrile at a flow rate of 0.8 mL min−1, an operating temperature of 30 °C, and a wavelength of 275 nm. Similarity analysis (SA), principal component analysis (PCA), and hierarchical cluster analysis (HCA) were used to analyze the data based on fingerprints. For fingerprint analysis, 27 peaks were selected as the common peaks to evaluate the similarities among different samples. The results of SA showed that the method permits to obtain desired linearity, precision, accuracy, and recovery. All samples were divided into three categories by PCA and HCA, and the concentration of the eight bioactive compounds varied significantly from different regions. It was demonstrated that chromatographic fingerprinting by HPLC combined with the simultaneous determination of eight bioactive compounds was a helpful method for the quality control of S. przewalskii.

Open access
Acta Chromatographica
Authors: Shaoshi Wen, Zixin Zhang, Xiaopeng Chen, Jinchang Liu, Haiyang Yu, Lifeng Han, Lijun Jin, Yi Zhang, and Tao Wang

Uric acid (UA) is the final product of purine metabolism in humans. Elevated serum UA levels lead to the development of hyperuricemia, gout, kidney diseases, and metabolic syndrome. Accurate determination of UA plays a critical role in clinical diagnosis and laboratory investigation. An ultra-performance liquid chromatography (UPLC) with ultraviolet detection method has been developed and validated for UA analysis. Separation was achieved by a Waters ethylene bridged hybrid (BEH) Amide column (50 mm × 2.1 mm i.d., 1.7 μm) with acetonitrile and 0.1% acetic acid in deionized water in the proportion of 90 to 10 (v/v) as the mobile phase. The limit of detection and limit of quantification were 0.09 and 0.18 μmol/L, respectively. The method was validated by evaluating recovery (98.37–104.20%), accuracy (0.47–0.90%), and precision (1.24–1.81% for intra-batch and 1.76–3.98% for inter-batch). This method was then applied to UA determination in rat serum of hyperuricemia model. The results from UPLC, high-performance liquid chromatography (HPLC), and uric acid kits (phosphor-tungstic acid-based kit and uricase-based kit) were compared. The UPLC results were in very good agreement with HPLC. The developed method could be employed as a useful tool for the determination of UA in biofluids.

Open access
Journal of Behavioral Addictions
Authors: Lu Li, Dan-Dan Xu, Jing-Xin Chai, Di Wang, Lin Li, Ling Zhang, Li Lu, Chee H. Ng, Gabor S. Ungvari, Song-Li Mei, and Yu-Tao Xiang

Background and aims

Internet addiction disorder (IAD) is common in university students. A number of studies have examined the prevalence of IAD in Chinese university students, but the results have been inconsistent. This is a meta-analysis of the prevalence of IAD and its associated factors in Chinese university students.

Methods

Both English (PubMed, PsycINFO, and Embase) and Chinese (Wan Fang Database and Chinese National Knowledge Infrastructure) databases were systematically and independently searched from their inception until January 16, 2017.

Results

Altogether 70 studies covering 122,454 university students were included in the meta-analysis. Using the random-effects model, the pooled overall prevalence of IAD was 11.3% (95% CI: 10.1%–12.5%). When using the 8-item Young Diagnostic Questionnaire, the 10-item modified Young Diagnostic Questionnaire, the 20-item Internet Addiction Test, and the 26-item Chen Internet Addiction Scale, the pooled prevalence of IAD was 8.4% (95% CI: 6.7%–10.4%), 9.3% (95% CI: 7.6%–11.4%), 11.2% (95% CI: 8.8%–14.3%), and 14.0% (95% CI: 10.6%–18.4%), respectively. Subgroup analyses revealed that the pooled prevalence of IAD was significantly associated with the measurement instrument (Q = 9.41, p = .024). Male gender, higher grade, and urban abode were also significantly associated with IAD. The prevalence of IAD was also higher in eastern and central of China than in its northern and western regions (10.7% vs. 8.1%, Q = 4.90, p = .027).

Conclusions

IAD is common among Chinese university students. Appropriate strategies for the prevention and treatment of IAD in this population need greater attention.

Open access

Abstract  

Vinylated polyhedral oligomeric silsesquioxane (POSS-M) was prepared by the reaction of POSS containing amine groups with acrylic acid. Azobenzene liquid crystalline copolymer (LCP-POSS) was then synthesized with 6.0 mol% POSS-M and 94.0 mol% acrylate monomer containing azobenzene liquid crystalline moiety (Azo-M) by free-radical copolymerization. Homopolymer of Azo-M (LCP) was also synthesized under the same conditions. Their thermal properties and liquid crystallinity were characterized by Thermal gravimetric analysis (TG), differential scanning calorimetry (DSC), Wide-angle X-ray diffraction experiments (XRD) and polarized optical micrographs (POM). The results showed that LCP-POSS has higher thermal stability and glass transition temperature than pure LCP due to the incorporation of the rigid cage-like POSS. Especially, LCP-POSS exhibits enantiotropic smectic and nematic liquid crystalline behaviors, its smectic-nematic transition temperature (T SN) and nematic-isotropic transition temperature (T NI) are higher than those of pure LCP, which may promote and extend its applications on stimuli-responsive materials and devices.

Restricted access
Journal of Behavioral Addictions
Authors: Shan-Shan Ma, Patrick D. Worhunsky, Jian-song Xu, Sarah W. Yip, Nan Zhou, Jin-Tao Zhang, Lu Liu, Ling-Jiao Wang, Ben Liu, Yuan-Wei Yao, Sheng Zhang, and Xiao-Yi Fang

Background

Cue-induced brain reactivity has been suggested to be a fundamental and important mechanism explaining the development, maintenance, and relapse of addiction, including Internet gaming disorder (IGD). Altered activity in addiction-related brain regions has been found during cue-reactivity in IGD using functional magnetic resonance imaging (fMRI), but less is known regarding the alterations of coordinated whole brain activity patterns in IGD.

Methods

To investigate the activity of temporally coherent, large-scale functional brain networks (FNs) during cue-reactivity in IGD, independent component analysis was applied to fMRI data from 29 male subjects with IGD and 23 matched healthy controls (HC) performing a cue-reactivity task involving Internet gaming stimuli (i.e., game cues) and general Internet surfing-related stimuli (i.e., control cues).

Results

Four FNs were identified that were related to the response to game cues relative to control cues and that showed altered engagement/disengagement in IGD compared with HC. These FNs included temporo-occipital and temporo-insula networks associated with sensory processing, a frontoparietal network involved in memory and executive functioning, and a dorsal-limbic network implicated in reward and motivation processing. Within IGD, game versus control engagement of the temporo-occipital and frontoparietal networks were positively correlated with IGD severity. Similarly, disengagement of temporo-insula network was negatively correlated with higher game-craving.

Discussion

These findings are consistent with altered cue-reactivity brain regions reported in substance-related addictions, providing evidence that IGD may represent a type of addiction. The identification of the networks might shed light on the mechanisms of the cue-induced craving and addictive Internet gaming behaviors.

Open access
Journal of Behavioral Addictions
Authors: Tao Luo, Lixia Qin, Limei Cheng, Sheng Wang, Zijun Zhu, Jiabing Xu, Haibo Chen, Qiaosheng Liu, Maorong Hu, Jianqin Tong, Wei Hao, Bo Wei, and Yanhui Liao

Abstract

Objective

Social media disorder (SMD) is an increasing problem, especially in adolescents. The lack of a consensual classification for SMD hinders the further development of the research field. The six components of Griffiths’ biopsychosocial model of addiction have been the most widely used criteria to assess and diagnosis SMD. The Bergen social media addiction scale (BSMAS) based on Griffiths’ six criteria is a widely used instrument to assess the symptoms and prevalence of SMD in populations. This study aims to: (1) determine the optimal cut-off point for the BSMAS to identify SMD among Chinese adolescents, and (2) evaluate the contribution of specific criteria to the diagnosis of SMD.

Method

Structured diagnostic interviews in a clinical sample (n = 252) were performed to determine the optimal clinical cut-off point for the BSMAS. The BSMAS was further used to investigate SMD in a community sample of 21,375 adolescents.

Results

The BSMAS score of 24 was determined as the best cut-off score based on the gold standards of clinical diagnosis. The estimated 12-month prevalence of SMD among Chinese adolescents was 3.5%. According to conditional inference trees analysis, the criteria “mood modification”, “conflict”, “withdrawal”, and “relapse” showed the higher predictive power for SMD diagnosis.

Conclusions

Results suggest that a BSMAS score of 24 is the optimal clinical cut-off score for future research that measure SMD and its impact on health among adolescents. Furthermore, criteria of “mood modification”, “conflict”, “withdrawal”, and “relapse” are the most relevant to the diagnosis of SMA in Chinese adolescents.

Open access