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Acta Chromatographica
Authors: Weijian Ye, Wei Sun, Ruijie Chen, Zhe Wang, Xiao Cui, Hui Zhang, Shuyi Qian, Qi Zheng, Yangfeng Zhou, Jiafeng Wan, Jiali Xu, Xianqin Wang, and Yunfang Zhou

Galangin (GAL), the major bioactive flavonol extracted from Alpinia officinarum Hance (Zingiberaceae), has attracted much attention due to its multiple biological activities. To develop a fast, reliable, and sensitive ultrahigh-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method for the quantification of GAL in rat plasma and mouse tissues. UHPLC–MS/MS using electrospray ionization operating in negative-ion mode was used to determinate GAL in 18 rats receiving three doses of GAL (2 and 9 mg/kg by intravenous injection, 5 mg/kg by oral administration), with six rats for each dose. Blood samples were collected at 0.0333, 0.25, 0.5, 1, 2, 4, 6 and 8 h. A total of 25 mice received 18 mg/kg GAL by intraperitoneal injection. Liver, heart, lung, spleen, brain, and kidney tissue samples were collected at 0.25, 0.5, 2, 4, and 6 h. The precision of the method was better than 12.1%, while the accuracy ranged from −4.8% to 8.1%. The results of pharmacokinetics demonstrated rapid GAL absorption (t max of 0.25 h), fast elimination (t 1/2 <1.1 h) after three different dosages, and an absolute bioavailability of ~7.6%. Tissue distribution analysis revealed abundant GAL in liver, kidney, spleen, and lung and smaller amounts in brain. The developed method proved fast (3 min), efficient, and reliable, with high selectivity for the quantitative analysis of GAL in biological samples. This is the first study to identify the target tissues of GAL, and the results may help to elucidate the mechanisms underlying its therapeutic effects in vivo.

Open access
Scientometrics
Authors: Jia Zheng, Zhi-Yun Zhao, Xu Zhang, Dar-Zen Chen, Mu-Hsuan Huang, Xiao-Ping Lei, Ze-Yu Zhang, and Yun-Hua Zhao

Abstract

Since China adopted Open-Up and Reformed Policy for global collaboration, China's science and technology have experienced an astounding growth. Papers and patents encompass valuable scientific and technological (S&T) information and collaborative efforts. This article studies China's international S&T collaboration from the perspective of paper and patent analysis. The results show that China's total papers and patents have continuously increased from 2004 to 2008, the papers and patents resulting from China's international collaboration also present a steady growth. However, there is a decline in the share of international collaboration papers and patents with a certain range due to the rapid independent R&D. China's international scientific collaboration (ISC) is broadly distributed over many countries, the USA being the most important ISC partners. China's international technological collaboration (ITC) is mainly carried out with USA and Taiwan, and Taiwan has been the most significant ITC partner of when taking countries’ patent output into account. Besides, ISC shows a continuous raise of Chinese papers’ citation. Even the countries with a small amount of papers and ISC with China, exert a positive influence on the impact of citation of Chinese papers as well. However, ITC does not always play an active role in the improvement of citation impact of Chinese patents.

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Abstract

Background and aims

Due to the rapid spread of the novel coronavirus disease 2019 (COVID-19), policies based on the nature of “spatial distancing” have been implemented and have resulted in school suspensions and online learning among schoolchildren. In order to examine the impact of such policies on schoolchildren, the aims of the present study were to (i) assess changes in the level of engagement in three internet-related activities (smartphone use, social media use, and gaming) before and during the COVID-19 outbreak, including prolonged and problematic engagement in these activities; (ii) investigate the differences of psychological distress before and after COVID-19 outbreak; and (iii) to use structural equation modeling to investigate the mediating roles of problematic internet-related behaviors in the causal relationships of psychological distress and time spent on internet-related activities.

Methods

Self-report measures were used to assess internet-related activities and psychological distress. Time spent on internet-related activities, problematic use of internet-related activities, and psychological distress were collected from primary school students (N = 535; 265 boys; M age = 10.32 years [SD = 0.84]). The data were first collected before the COVID-19 outbreak (i.e., early November 2019) and then collected again during the school suspension due to COVID-19 outbreak (i.e., end of March 2020) for comparisons of changes.

Results

Schoolchildren spent significantly more time on the smartphone (increased 1.02 h daily; P < 0.001) and social media (increased 0.73 h daily; P < 0.001) but not gaming (increased 0.14 h daily; P = 0.07) during the school suspension compared to the baseline. Schoolchildren who increased by 15 or 30 min daily on internet-related activities showed an increased level of psychological distress. The association between problematic use of social media and psychological distress was stronger during the school suspension (β = 0.584) than at the baseline (β = 0.451; P < 0.001).

Conclusion

Increased problematic use of internet-related activities among schoolchildren was associated with greater psychological distress. Parents should therefore monitor internet-related activities and psychological distress of their children to support their mental health.

Open access
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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Journal of Radioanalytical and Nuclear Chemistry
Authors: Chuan-Min Qi, Yong He, Xiao Wang, Man Feng, Jing-Li Xu, Rui Ding, Hang Liu, Yu-Rong Chen, Fang Li, Zhao-Hui Zhu, Yong-Hong Dang, Shu-Ting Zhang, and Ying Xie

Abstract  

d-glucosamine at concentration of certain range could kill tumor cells without influencing normal cells. There are also some reports on the antitumor activity of d-glucosamine and its derivatives in murine models. It was therefore postulated that d-glucosamine might have the potential to invade tumor cells. We designed and radiosynthesized a glucosamine derivative, N-(2-[18F]fluoro-4-nitrobenzoyl)glucosamine ([18F]FNBG([18F]7)). Evaluations in vitro and in vivo were performed on tumor bearing mice. Excitingly, the radiochemical purity of [18F]FNBG([18F]7) was 99%, and besides the best radiochemical yield was up to 35%. The best T/Bl (Tumor/Blood) and T/M (Tumor/Muscle) ratios of [18F]FNBG([18F]7) were 4.40 and 4.84. Although [18F]FNBG([18F]7) deserved further studies, the results revealed it might become a potential PET imaging agent for detecting tumors.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Yong He, Rui Ding, Hang Liu, Xiao Wang, Jing-Li Xu, Man Feng, Yu-Rong Chen, Chuan-Min Qi, Cheng Peng, Zhao-Hui Zhu, Yong-Hong Dang, Ming Wang, and Yun-Chuan Ma

Abstract  

As degradation product of Antineoplaston A10 in vivo, phenylacetyl glutamine showed antitumor activities. According to literatures, we designed and radiosynthesized a phenylacetyl glutamine derivative, which was achieved under a mild reaction condition. Evaluations in vitro and in vivo were performed on tumor bearing mice. Excitingly, the radiochemical purity of (S)-2-((S)-2-(4-(3-fluoropropyl)benzamido)-3-phenylpropanamido)pentanedioic acid ([18F]FBPPA) was 98%, and besides the best radiochemical yield was up to 46%. T/Bl (Tumor/Blood) and T/M (Tumor/Muscle) ratios of [18F]FBPPA at 60 min post injection were 2.33 and 3.51. Meanwhile, it showed satisfied stability in vitro and in vivo, compared with 2-[18F]fluorodeoxyglucose ([18F]FDG). Although [18F]FBPPA deserved further studies to make optimizations on its structure, the results revealed it might become a potential PET imaging agent for detecting tumors.

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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