ObjectiveTo prepare a recombinant PETase with a dual-catalytic-triad and to evaluate its efficiency in the biodegradation of polyethylene terephthalate （PET）. MethodsBased on the crystal structure of wild-type PETase， point mutations （T88H/L117D） were introduced via site-directed mutagenesis. The recombinant protein was prepared using prokaryotic expression and chromatography purification techniques. The enzymatic hydrolysis of the mutant PETase was assessed by relatively quantifying the products mono （2-hydroxyethyl） terephthalate （MHET） and terephthalic acid （TPA）. ResultsBoth wild-type and mutant PETases accumulated as inclusion bodies， accounting for approximately 20% of the total bacterial protein. After solubilization in urea， the proteins were eluted at 300 mmol/L imidazole during affinity chromatography purification， with concentrations of 1.824 and 1.833 mg/mL and purities of 83.11% and 84.32%， respectively. Subsequent anion-exchange chromatography yielded highly pure enzymes in the 200 mmol/L NaCl fraction： 2.776 mg/mL （96.86% purity） for the wild type and 1.967 mg/mL （95.13% purity） for the mutant. Following refolding， the final concentrations were 0.484 mg/mL for the wild type and 0.991 mg/mL for the mutant. Hydrolysis assays revealed that the mutant released MHET and TPA at （237.67±17.00）% and （197.33±12.01）% of the wild-type levels， respectively. ConclusionThe T88H/L117D dual-catalytic-triad PETase is successfully prepared and it significantly enhanced PET-degrading activity， thus， it′s a promising biocatalyst for PET bioremediation.

OBJECTIVE To investigate the effects of Tripterygium wilfordii multiglycoside （TWM） on renal injury in diabetic nephropathy （DN） rats through tumor protein p53/microRNA-214 （miR-214）/UNC-51-like kinase 1 （ULK1） axis. METHODS Male SD rats were randomly divided into normal group （n＝6） and modeling group （n＝28）； the modeling group was fed with high fat and high glucose plus intraperitoneal injection of streptozotocin to establish DN model. The modeled rats were randomly divided into model group， valsartan group [8.33 mg/（kg·d）] and TWM group[6.25 mg/（kg·d）]， with 8 rats in each group. Rats in each group were gavaged with the corresponding medication or normal saline， once a day， for 6 consecutive weeks. After the last medication， liver and renal function indexes [24 h urinary total protein （24 h-UTP）， blood urea nitrogen （BUN）， serum creatinine （SCr）， albumin （ALB）， alanine transaminase （ALT）]， blood lipid indexes （triglycerides， total cholesterol） and blood glucose index （fasting blood glucose） in urine/blood sample of rats were detected in each group. Renal pathologic change was observed， protein and mRNA expressions of p53， ULK1， Beclin-1 and microtubule-associated protein 1 light chain 3 （LC3）， and expression of miR-214 in renal tissue were also determined. RESULTS Compared with the normal group， the renal tubular epithelium of rats in the model group showed obvious edema， cell swelling， accompanied by lymphocyte infiltration； the levels of 24h-UTP， BUN， SCr， ALT and glycolipid indexes， the expressions of p53 protein and mRNA， as well as the expression of miR-214 in rats in the model group and administration groups were significantly increased or up-regulated， while ALB level， LC3-Ⅱ/LC3-Ⅰ， the expressions of LC3 mRNA， the expressions of ULK1， Beclin-1 protein and mRNA were significantly decreased or down-regulated （P＜0.01）. Compared with the model group， the histopathological damage of the kidney in rats was improved in administration groups； the levels of 24 h-UTP， BUN， SCr， ALT and glycolipid indexes， the expressions of p53 protein and mRNA， as well as the expression of miR-214 were all significantly decreased or down-regulated， while ALB level， LC3-Ⅱ/LC3-Ⅰ， the expressions of LC3 mRNA， the expressions of ULK1 and Beclin-1 protein and mRNA were significantly increased or up-regulated （P＜0.01）. CONCLUSIONS TG can alleviate renal damage in DN rats， and improve their liver and renal function， as well as glucose and lipid levels. These effects may be related to the regulation of the p53/miR-214/ULK1 axis and the restoration of cellular autophagy.

Objective To explore the pathogenesis of Alzheimer's disease by examining the effects of dihydroartemisinin(DHA)on cognitive behavior,hippocampal,cerebral cortex and retinal cell morphology,β-amyloid(Aβ)and autophagy-related proteins in 5×FAD mice.Methods Twenty 5×FAD mice and 5 wild type(WT)mice were selected,all of which were female.The 5×FAD mice were randomly divided into model(M)group,donepezil(D)group,low-dose DHA(DHA-L)group,and high-dose DHA(DHA-H)group.The WT and M groups were not treated,and the D group was given donepezil 0.1 mg/kg per day.DHA-L group and DHA-H group were given 10 mg/kg and 20 mg/kg DHA per day,respectively.Group D,group DHA-L and group DHA-H were given intragastric administration once a day for 3 months.The changes of in cognitive behavior were measured by Morris experiment.HE staining was used to observe the arrangement and morphology of nerve cells in cerebral cortex,hippocampus and retina.The expressions of Aβ protein in cerebral cortex,hippocampus and retina were detected by immunohistochemistry.Western blotting detected the expression of autophagy related proteins(LC3-Ⅰ,LC3-Ⅱ,Beclin-1,P62,β-actin).Results The DHA-H group and the D group exhibited more frequent adoption of both linear and trending exploration routes.Compared to the model group,significant differences in the contents of Aβ in the hippocampal CA1,cerebral cortex S1,and retinal were observed(P＜0.0001)in the other four groups.The analysis also showed significant differences in autophagy-associated proteins between the DHA-L,DHA-H,and model groups(P＜0.01).Conclusion DHA improves cognitive function and increases the number of nerve cells in mice.It also reduces Aβ content in the cerebral cortex,hippocampus,and retina,along with improving autophagy-associated protein deposition in mice.

Objective To investigate the effect of up-regulating tumor necrosis factor alpha induced protein 3(TNFAIP3)expression on hippocampal neurons in mice with cerebral ischemia-reperfusion.Methods The mice were randomly divided into 6 groups:sham group,sham empty vector group(sham-),sham TNFAIP3 high expression group(sham+),model group,model empty vector group(model-),model TNFAIP3 high expression group(model+).A mouse model of middle cerebral artery occlusion and cerebral ischemia-reperfusion was established using the suture method.After the successful establishment of the model,lentivirus was injected into the hippocampus 24 hours later.Two weeks later,samples were collected and Western blotting was used to detect the expressions of TNFAIP3 and ERK signaling pathway proteins.The changes in ischemic area were observed by 2,3,5-triphenyltetrazolium chloride(TTC)staining;HE staining was used to observe the morphological changes of hippocampal neurons,and ELISA was used to detect the expressions of lipoprotein-associated phospholipase A2(Lp-PLA2)and interleukin(IL)-8.Results The results of Western blotting indicated that the TNFAIP3 expression in the model group decreased significantly compared with the sham group(P＜0.05);Compared with the model group,there was no significant change in TNFAIP3 expression in the model-group(P＞0.05);The TNFAIP3 expression in the model+group increased significantly compared with the model group and model-group(P＜0.05).Compared with the sham group,the results of the sham+group showed that the ischemic area had no significant changes in TTC staining,and there were no significant changes in hippocampal neuronal morphology,and the expressions ERK signaling pathway proteins,Lp-PLA2 and IL-8(P＞0.05);Compared with the sham-and sham+groups,the model group showed an increase in ischemic area,significant damage to hippocampal neurons,a decrease in the number of Nissl bodies,and a significant increase in the expressions of ERK signaling pathway proteins,Lp-PLA2,and IL-8(P＜0.05);Compared to the model-group,the model+group showed a decrease in ischemic area,an increase in the number of neurons in the hippocampus and the number of Nissl bodies,and a significant decrease in the expressions of ERK signaling pathway proteins,Lp-PLA2,and IL-8(P＜0.05).Conclusion Up-regulation of TNFAIP3 may be one of the methods for repairing hippocampal neuronal damage caused by cerebral ischemia reperfusion.

Aim To investigate the intervention effect of Rehmannia radix water extract on bleomycin(BLM)-induced pulmonary fibrosis in mice combined with metabolomics and to reveal the potential mechanism,in order to provide new ideas for clinical treatment of pul-monary fibrosis.Methods Male C57BL/6N mice were randomly divided into the control group,model group,pirfenidone group(positive control,PFD,270 mg·kg-1),and low dose(DH-L,4.55 g·kg-1)group,medium dose(DH-M,9.1 g·kg-1)group and high dose(DH-H,18.2 g·kg-1)group of Rehman-nia.Except for the control group,BLM(5 mg·kg-1)was instilled into the trachea to establish the model of pulmonary fibrosis in the other groups.The survival rate,lung index and blood oxygen saturation of mice in each group were evaluated.HE and Masson staining were used to observe the pathological changes of lung tissue.WBP was used to detect lung function.Flow cytometry was used to detect the apoptosis of primary lung cells,ROS and immune cells.ELISA was used to detect the levels of fibrosis markers and inflammatory factors(α-SMA,collagen Ⅰ,collagen Ⅲ,TGF-β1,TNF-α,IL-1 β,and IL-6).Biochemical method was employed to detect the contents of GSH-Px,T-SOD and MDA.Liquid chromatograph mass spectrometer(LC-MS)metabolomics was used to analyze the changes of serum metabolic profile.Results Water extract of Re-hmannia significantly increased the survival rate,oxy-gen saturation and lung function of mice with pulmona-ry fibrosis,reduced the lung coefficient,ameliorated pathological damage and collagen deposition in lung tissue,reduced the levels of apoptosis and oxidative stress,and down-regulated the levels of inflammatory factors in lung tissue.It regulated the levels of metabo-lites such as bile acid metabolism,sphingolipid metabo-lism,and unsaturated fatty acid metabolism.Conclu-sions Water extract of Rehmannia inhibits lung injury and collagen deposition in mice with pulmonary fibrosis by inhibiting inflammatory response,which may be a-chieved by regulating the levels of inflammatory factors through the metabolic pathways of bile acid and sphin-golipid.

Aim To investigate the intervention effect of Rehmannia radix water extract on bleomycin(BLM)-induced pulmonary fibrosis in mice combined with metabolomics and to reveal the potential mechanism,in order to provide new ideas for clinical treatment of pul-monary fibrosis.Methods Male C57BL/6N mice were randomly divided into the control group,model group,pirfenidone group(positive control,PFD,270 mg·kg-1),and low dose(DH-L,4.55 g·kg-1)group,medium dose(DH-M,9.1 g·kg-1)group and high dose(DH-H,18.2 g·kg-1)group of Rehman-nia.Except for the control group,BLM(5 mg·kg-1)was instilled into the trachea to establish the model of pulmonary fibrosis in the other groups.The survival rate,lung index and blood oxygen saturation of mice in each group were evaluated.HE and Masson staining were used to observe the pathological changes of lung tissue.WBP was used to detect lung function.Flow cytometry was used to detect the apoptosis of primary lung cells,ROS and immune cells.ELISA was used to detect the levels of fibrosis markers and inflammatory factors(α-SMA,collagen Ⅰ,collagen Ⅲ,TGF-β1,TNF-α,IL-1 β,and IL-6).Biochemical method was employed to detect the contents of GSH-Px,T-SOD and MDA.Liquid chromatograph mass spectrometer(LC-MS)metabolomics was used to analyze the changes of serum metabolic profile.Results Water extract of Re-hmannia significantly increased the survival rate,oxy-gen saturation and lung function of mice with pulmona-ry fibrosis,reduced the lung coefficient,ameliorated pathological damage and collagen deposition in lung tissue,reduced the levels of apoptosis and oxidative stress,and down-regulated the levels of inflammatory factors in lung tissue.It regulated the levels of metabo-lites such as bile acid metabolism,sphingolipid metabo-lism,and unsaturated fatty acid metabolism.Conclu-sions Water extract of Rehmannia inhibits lung injury and collagen deposition in mice with pulmonary fibrosis by inhibiting inflammatory response,which may be a-chieved by regulating the levels of inflammatory factors through the metabolic pathways of bile acid and sphin-golipid.

Objective: Self-determination theory (SDT) deems that people have three causality orientations: autonomy orientation, control orientation, and impersonal orientation. Previous studies suggested that lower autonomy orientation or higher control and impersonal orientations may be associated with more addictive behaviors. Our study aimed to investigate if these associations exist in Internet gaming disorder (IGD), and if sensation seeking, anxiety, and depression could influence the associations between causality orientations and IGD symptoms. Methods: A total of 1,400 college students completed the Internet Gaming Disorder Scale, General Causality Orientation Scale, Brief Sensation Seeking Scale, Generalized Anxiety Disorder Scale, and Patient Health Questionnaire. Correlation, multiple linear regressions, structural equation model (SEM) analyses, and moderation analyses were conducted to explore the associations. Results: The control and impersonal orientations were positively associated with IGD symptoms, while the autonomy orientation was negatively associated with them. Moreover, SEM analyses showed that the autonomy-IGD relationship was totally mediated by anxiety and depression, the impersonal-IGD relationship was partially mediated by anxiety, and the control-IGD relationship was partially mediated by depression. Finally, the effects of causality orientations on IGD were moderated by sensation seeking. Conclusion Overall, autonomy orientation is linked to fewer gaming problems, whereas control and impersonal orientations are associated with more gaming problems. Moreover, the relationships between causality orientations and IGD symptoms are mediated by anxiety and depression and moderated by sensation seeking. Our findings inform theory on the motivations of gaming behaviors and may shed light on the prevention and intervention of IGD from the perspective of SDT.

Objective: Self-determination theory (SDT) deems that people have three causality orientations: autonomy orientation, control orientation, and impersonal orientation. Previous studies suggested that lower autonomy orientation or higher control and impersonal orientations may be associated with more addictive behaviors. Our study aimed to investigate if these associations exist in Internet gaming disorder (IGD), and if sensation seeking, anxiety, and depression could influence the associations between causality orientations and IGD symptoms. Methods: A total of 1,400 college students completed the Internet Gaming Disorder Scale, General Causality Orientation Scale, Brief Sensation Seeking Scale, Generalized Anxiety Disorder Scale, and Patient Health Questionnaire. Correlation, multiple linear regressions, structural equation model (SEM) analyses, and moderation analyses were conducted to explore the associations. Results: The control and impersonal orientations were positively associated with IGD symptoms, while the autonomy orientation was negatively associated with them. Moreover, SEM analyses showed that the autonomy-IGD relationship was totally mediated by anxiety and depression, the impersonal-IGD relationship was partially mediated by anxiety, and the control-IGD relationship was partially mediated by depression. Finally, the effects of causality orientations on IGD were moderated by sensation seeking. Conclusion Overall, autonomy orientation is linked to fewer gaming problems, whereas control and impersonal orientations are associated with more gaming problems. Moreover, the relationships between causality orientations and IGD symptoms are mediated by anxiety and depression and moderated by sensation seeking. Our findings inform theory on the motivations of gaming behaviors and may shed light on the prevention and intervention of IGD from the perspective of SDT.

Objective: Self-determination theory (SDT) deems that people have three causality orientations: autonomy orientation, control orientation, and impersonal orientation. Previous studies suggested that lower autonomy orientation or higher control and impersonal orientations may be associated with more addictive behaviors. Our study aimed to investigate if these associations exist in Internet gaming disorder (IGD), and if sensation seeking, anxiety, and depression could influence the associations between causality orientations and IGD symptoms. Methods: A total of 1,400 college students completed the Internet Gaming Disorder Scale, General Causality Orientation Scale, Brief Sensation Seeking Scale, Generalized Anxiety Disorder Scale, and Patient Health Questionnaire. Correlation, multiple linear regressions, structural equation model (SEM) analyses, and moderation analyses were conducted to explore the associations. Results: The control and impersonal orientations were positively associated with IGD symptoms, while the autonomy orientation was negatively associated with them. Moreover, SEM analyses showed that the autonomy-IGD relationship was totally mediated by anxiety and depression, the impersonal-IGD relationship was partially mediated by anxiety, and the control-IGD relationship was partially mediated by depression. Finally, the effects of causality orientations on IGD were moderated by sensation seeking. Conclusion Overall, autonomy orientation is linked to fewer gaming problems, whereas control and impersonal orientations are associated with more gaming problems. Moreover, the relationships between causality orientations and IGD symptoms are mediated by anxiety and depression and moderated by sensation seeking. Our findings inform theory on the motivations of gaming behaviors and may shed light on the prevention and intervention of IGD from the perspective of SDT.

Objective: Self-determination theory (SDT) deems that people have three causality orientations: autonomy orientation, control orientation, and impersonal orientation. Previous studies suggested that lower autonomy orientation or higher control and impersonal orientations may be associated with more addictive behaviors. Our study aimed to investigate if these associations exist in Internet gaming disorder (IGD), and if sensation seeking, anxiety, and depression could influence the associations between causality orientations and IGD symptoms. Methods: A total of 1,400 college students completed the Internet Gaming Disorder Scale, General Causality Orientation Scale, Brief Sensation Seeking Scale, Generalized Anxiety Disorder Scale, and Patient Health Questionnaire. Correlation, multiple linear regressions, structural equation model (SEM) analyses, and moderation analyses were conducted to explore the associations. Results: The control and impersonal orientations were positively associated with IGD symptoms, while the autonomy orientation was negatively associated with them. Moreover, SEM analyses showed that the autonomy-IGD relationship was totally mediated by anxiety and depression, the impersonal-IGD relationship was partially mediated by anxiety, and the control-IGD relationship was partially mediated by depression. Finally, the effects of causality orientations on IGD were moderated by sensation seeking. Conclusion Overall, autonomy orientation is linked to fewer gaming problems, whereas control and impersonal orientations are associated with more gaming problems. Moreover, the relationships between causality orientations and IGD symptoms are mediated by anxiety and depression and moderated by sensation seeking. Our findings inform theory on the motivations of gaming behaviors and may shed light on the prevention and intervention of IGD from the perspective of SDT.