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Explosive growth characteristics of 5.6–560 nm particles and deposition in human respiratory during spring in Yangtze River Delta region,China
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作者 Yingru Gong Jinping Ou +10 位作者 Qihou Hu Chengzhi Xing Yizhi Zhu Yuhui Wan Danni Wang Chao Zhang lixin guan Jiaxuan Feng Xiangguang Ji Xinqi Wang Cheng Liu 《Journal of Environmental Sciences》 2025年第9期372-381,共10页
Studying the contribution of regional transport to ultrafine particles(UFPs)and the deposition effect of nanoscale particles in human respiratory system is conducive to exploring the impact of atmospheric particles on... Studying the contribution of regional transport to ultrafine particles(UFPs)and the deposition effect of nanoscale particles in human respiratory system is conducive to exploring the impact of atmospheric particles on the environment and human health.Based on the data set of number concentration spectrum in the particle size range of 5.6–560 nm in the spring of Hefei,the Yangtze River Delta region obtained by a fast mobility particle sizer,the explosive growth characteristics,potential source identification and deposition flux analysis of UFPs were systematically studied.The results showed that the frequency of new particle formation(NPF)events during spring was 31.5%.SO_(2) and O_(3) contribute to NPF events.Daytime,higher temperature,stronger solar radiation and lower humidity were more conducive to the explosive growth of UFPs.In addition,regional transport of pollutants from the cities around Hefei played an important role in the accumulation mode particles,which were mainly affected by the land-source air mass from northwest Jiangsu(23.64%)and the sea-source air mass from the Yellow Sea(23.99%).It was worth noting that approximately 10,406 ng of UFPs enters the human respiratory system every day.Themain deposition area of 5.6–560 nm nanoscale particles was alveolar,5.6–400 nm is more likely to be deposited on alveolar,while nanoscale particles with particle size between 400 and 560 nm is more likely to be deposited on head airways.This study identified the deposition risk of nanoscale particles in the respiratory system under different particle sizes. 展开更多
关键词 Ultrafine particles New particle formation Driving factor Deposition dose Potential source
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Expression profiles of microRNAs after focal cerebral ischemia/reperfusion injury in rats 被引量:13
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作者 Fengguo Zhai Xiuping Zhang +4 位作者 Yue guan Xudong Yang Yang Li Gaochen Song lixin guan 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第12期917-923,共7页
Rat models of focal cerebral ischemia/reperfusion injury were established by occlusion of the middle cerebral artery. Microarray analysis showed that 24 hours after cerebral ischemia, there were nine up-regulated and ... Rat models of focal cerebral ischemia/reperfusion injury were established by occlusion of the middle cerebral artery. Microarray analysis showed that 24 hours after cerebral ischemia, there were nine up-regulated and 27 down-regulated microRNA genes in cortical tissue. Bioinformatic analysis showed that bcl-2 was the target gene of microRNA-384-5p and microRNA-494, and caspase-3 was the target gene of microRNA-129, microRNA-320 and microRNA-326. Real-time PCR and western blot analyses showed that 24 hours after cerebral ischemia, bcl-2 mRNA and protein levels in brain tissue were significantly decreased, while caspase-3 mRNA and protein levels were significantly increased. This suggests that following cerebral ischemia, differentially expressed microRNA-384-5p, microRNA-494, microRNA-320, microRNA-129 and microRNA-326 can regulate bcl-2 and caspase-3 expression in brain tissue. 展开更多
关键词 focal cerebral ischemia MICRORNA APOPTOSIS BCL-2 CASPASE-3 neural regeneration
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Water Quality Evaluation Using Back Propagation Artificial Neural Network Based on Self-Adaptive Particle Swarm Optimization Algorithm and Chaos Theory 被引量:4
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作者 Mengshan Li Wei Wu +2 位作者 Bingsheng Chen lixin guan Yan Wu 《Computational Water, Energy, and Environmental Engineering》 2017年第3期229-242,共14页
To overcome the shortcomings of the traditional methods of water quality evaluation, in this paper, a novel model combines particle swarm optimization (PSO), chaos theory, self-adaptive strategy and back propagation a... To overcome the shortcomings of the traditional methods of water quality evaluation, in this paper, a novel model combines particle swarm optimization (PSO), chaos theory, self-adaptive strategy and back propagation artificial neural network (BP ANN) that was proposed to evaluate the water quality of Weihe River in China. An improved PSO algorithm with a self-adaptive inertia weight and a chaotic learning factor tuned by logistic function was developed and used to optimize the network parameters of BP ANN. The values of average absolute deviation (AAD), root mean square error of prediction (RMSEP) and squared correlation coefficient are 0.0061, 0.0163 and 0.9903, respectively. Compared with other methods, such as BP ANN, and PSO BP ANN, the proposed model displays optimal prediction performance with high precision and good correlation. The results show that the proposed method has the good prediction ability for evaluating water quality. It is convenient, reliable and high precision, which provides good analysis and evaluation method for water quality. 展开更多
关键词 Water Quality PARTICLE SWARM Optimization BP ANN Improved PSO
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Influence of Panax quinquefolium saponins on increased intracellular Ca^(2+) in PC12 cells
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作者 lixin guan Xiudong Jin +5 位作者 Yanhui Chu Yufei Zhang Yan Wu Xin Yi Fengguo Zhai Men clquan Li 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第3期225-229,共5页
BACKGROUND: Previous studies have demonstrated that intracellular Ca^2+ ([Ca^2+]) overload, excitotoxicity, free radical injury, and nitric oxide toxicity are involved in mechanisms of neuronal death in the ische... BACKGROUND: Previous studies have demonstrated that intracellular Ca^2+ ([Ca^2+]) overload, excitotoxicity, free radical injury, and nitric oxide toxicity are involved in mechanisms of neuronal death in the ischemic brain. OBJECTIVE: To investigate the influence of Panax quinquefo/ium saponins (PQS) on multiple factors-induced Ca^2+ overload in the rat pheochromocytoma (PC12) cell line. DESIGN, TIME AND SETTING: Intergroup comparison, in vitro study. The experiment was performed at the Heilongjiang Key Laboratory of Anti-fibrosis Biotherapy, Mudanjiang Medical University between November 2007 and April 2008. MATERIALS- In vitro cultured PC12 cells in the logarithmic phase were assigned into blank control, model, and drug treatment groups (10 μmol/L nimodipine; 40 μg/L, 100 μg/L, and 250 μg/L PQS). Nimodipine was purchased from Jiangsu Yangtze River Pharmacy Group Co., China; PQS (purity 〉 95%, HLPC grade) was provided by School of Basic Medical Sciences, Jilin University. Caffeine, Na2S2O4, L-glutamic acid (Glu), Fura-2/AM, and calcium ionophore A23187 were purchased from Sigma, USA. METHODS: PC12 cells in the model and drug treatment groups were separately incubated in glucose-free Hank's buffered saline solution + Na2S2O4 (2 mmol/L) for 6 hours, Glu (200 μmot/L) plus A23187 (0.05 μmol/L) for 6 hours, KCI (50 mmol/L) for 1 hour, and caffeine (5 mmol/L) for 3 hours to establish models of intracellular Ca^2+ overload induced by oxygen and glucose deprivation, Glu, A23187, high K+, or caffeine. In addition, control cells were incubated in high-glucose DMEM culture medium. MAIN OUTCOME MEASURES: [Ca^2+]i changes in PC12 cells exposed to oxygen-glucose deprivation, Glu, A23187, high K^+, or caffeine were detected using spectrofluorometer. RESULTS: PQS blocked the [Ca^2+]i increase induced by oxygen-glucose deprivation, Glu, A23187, high K+, or caffeine. In particular, high-dose PQS was most effective (P 〈 0.01). PQS significantly inhibited Glu- or caffeine-induced [Ca^2+]i increases in the absence of extracellular Ca^2+, but nimodipine did not. CONCLUSION: PQS blocked intracellular Ca^2+ overload induced by oxygen-glucose deprivation, Glu, A23187, high K^+, or caffeine. This mechanism might be involved in the attenuation of neuronal apoptosis following ischemic brain injury. 展开更多
关键词 Panax quinquefolium saponins intracellular Ca^2+ PC12 cells oxygen-glucose deprivation FURA-2/AM
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Computational approaches for predicting drug-disease associations:a comprehensive review
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作者 Zhaoyang HUANG Zhichao XIAO +2 位作者 Chunyan AO lixin guan Liang YU 《Frontiers of Computer Science》 2025年第5期113-127,共15页
In recent decades,traditional drug research and development have been facing challenges such as high cost,long timelines,and high risks.To address these issues,many computational approaches have been proposed for pred... In recent decades,traditional drug research and development have been facing challenges such as high cost,long timelines,and high risks.To address these issues,many computational approaches have been proposed for predicting the relationship between drugs and diseases through drug repositioning,aiming to reduce the cost,development cycle and risks associated with developing new drugs.Researchers have explored different computational methods to predict drugdisease associations,including drug side effects-disease associations,drug-target associations,and miRNA-disease associations.In this comprehensive review,we focus on recent advances in predicting drug-disease association methods for drug repositioning.We first categorize these methods into several groups,including neural network-based algorithms,matrix-based algorithms,recommendation algorithms,linkbased reasoning algorithms,and text mining and semantic reasoning.Then,we compare the prediction performance of existing drug-disease association prediction algorithms.Lastly,we discuss the current challenges and future perspectives in the field of drug-disease associations. 展开更多
关键词 drug-disease association association prediction drug repositioning machine learning
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