Collagen, a vital matrix protein for various tissue and functions in animals, is widely applied in biomaterials. In type Ⅰ collagen, missense mutations of glycine (Gly) in the Gly-Xaa-Yaa triplet of the triple helix are a major cause of osteogenesis imperfecta (OI). Clinical manifestations exhibit marked heterogeneity, spanning a broad disease spectrum from mild skeletal fragility (Type Ⅰ) to severe limb deformities (Type Ⅲ) and perinatal lethal forms (Type Ⅱ). This study utilized recombinant collagen as a model to further elucidate whether Gly→Ala/Val mutations at the N-terminus of the integrin-binding sequence GFPGER affect collagen structure and function, and to explore the underlying mechanisms by which missense mutations impact the biological function of collagen. By introducing Ala and Val substitutions at seven Gly positions N-terminal to the GFPGER sequence, we systematically assessed the effects of these amino acid replacements on the triple-helical structure, thermal stability, integrin-binding ability, and cell adhesion of recombinant collagen. All constructs formed a stable triple-helix structure, with slightly compromised thermal stability. Gly→Val substitutions increased the susceptibility of recombinant collagen to trypsin, which suggested local conformational perturbations in the triple helix. In addition, Gly→Val substitutions significantly reduced the integrin-binding affinity and decreased HT1080 cell adhesion, with the effects stronger than Gly→Ala substitutions. Compared with Gly→Ala substitutions, substitution of Gly with the larger residue Val had enhanced negative effects on the structure and function of recombinant collagen. These findings provide new insights into the molecular mechanisms of osteogenesis imperfecta and offer theoretical references and experimental foundations for the design of collagen sequences and the development of collagen-based biomaterials.
Recombinant Proteins/biosynthesis* ; Glycine/genetics* ; Humans ; Osteogenesis Imperfecta/genetics* ; Integrins/metabolism* ; Collagen/metabolism* ; Collagen Type I/metabolism* ; Amino Acid Substitution ; Mutation ; Mutation, Missense

Objective To explore the correlation between stroke etiology and clinical and imaging features in patients with acute ischemic stroke(AIS)due to large vessel occlusion treated by intravascular thrombectomy.Methods A total of 213 patients with AIS and endovascular embolectomy in our hospital from Oct.2016 to Jun.2018 were enrolled retrospectively.According to the etiological classification criteria of Trial of Org 10172 in Acute Stroke Treatment(TOAST),there were 116 cases of cardioembolism and 97 cases of non-cardioembolism.Multivariate logistic regression analysis was used to screen the clinical and imaging characteristics for identifying cardioembolism and non-cardioembolism.Results Compared with non-cardioembolism AIS,cardioembolism AIS was associated with higher NIHSS scores(adjusted odds ratio[OR]=1.09,95%confidence interval[95%CI]1.01-1.18,P=0.02),atrial fibrillation(adjusted OR=76.46,95%CI 26.75-218.51,P＜0.01),absence of hypertension(adjusted OR=0.32,95%CI 0.12-0.84,P=0.02),antiplatelet drug use(adjusted OR=5.03,95%CI 1.22-20.63,P=0.03),shorter onset-to-puncture time(adjusted OR=0.998,95%CI 0.996-1.000,P=0.04),and presence of hyperdense artery sign(HAS)(adjusted OR=4.45,95%CI 1.47-13.49,P=0.01).Conclusion There are some differences in clinical and imaging characteristics between patients with cardioembolism and non-cardioembolism AIS.The occurrence of HAS suggests a higher probability of cardioembolism in AIS patients.

Objective To study the effect of Liuwei Dihuangwan on autophagy level and its mechanism in SAMP8 mice and Aβ-stimulated BV2 cell model,and to explore the molecular mechanism of tonifying the kidney and filling up the essence to prevent and control Alzheimer's disease(AD)through interfering with autophagy.Methods Ten 7-month-old male anti-aging mice(SAMR1)were taken as the normal group,and 40 7-month-old male rapid aging mice(SAMP8)were randomly control and model groups,equal volumes of saline were administered by gavage twice a day for 4 weeks,and the levels of Aβ expression in the hippocampus of the mice in each group were detected by immunofluorescence;The expression levels of FcγRⅡB,c-Src and SHP-1 in the hippocampus of each group were detected by Western blot;BV2 cells were cultured and Fcγ receptor Ⅱ-b(FcγRⅡB)overexpression vectors were constructed;the AD state cell model was established by treating the BV2 cells with 5 μmol·L-1 Aβ1-42,and the Liuwei Dihuangwan drug-containing serum was prepared.The cells were divided into NC group,Aβ1-42 group,blank serum group,drug-containing serum group,Vector group,FcγRⅡB OE group,and drug-containing serum+FcγRⅡB OE group;immunofluorescence was used to detect the expression level of Aβ protein in the cells of each group;Western blot was used to detect the expression level of p62,LC3 Ⅱ/Ⅰ,FcγRⅡB,SHP-1,and c-Src in cells of each group.Results Compared with the normal group,the hippocampal Aβ,FcγRⅡB,SHP-1,and c-Src expression levels in the model group of mice were significantly higher(P<0.01),and compared with the model group,the expression levels of Aβ,FcγRⅡB,SHP-1,and c-Src in the low-,medium-,and high-dose groups of Liuwei Dihuangwan were significantly lower(P<0.01),it also showed a significant dose dependent relationship.Compared with NC group,the protein expressions of Aβ,p62,FcγRⅡB,SHP-1 and c-Src in Aβ1-42 group were significantly increased(P<0.01),and LC3Ⅱ/Ⅰ was significantly decreased(P<0.01);Compared with Aβ1-42 group and blank serum group,the protein expressions of Aβ,p62,FcγRⅡB,SHP-1 and c-Src in drug-containing serum group were significantly decreased(P<0.01),and LC3Ⅱ/Ⅰ was significantly increased(P<0.01);Compared with NC group and Vector group,the expression of Aβ in FcγRⅡB OE group was increased,the protein expressions of p62,FcγRⅡB,SHP-1 and c-Src were significantly increased(P<0.01),and LC3Ⅱ/Ⅰ was significantly decreased(P<0.01);Compared with the drug-containing serum group,the protein expressions of Aβ,p62,FcγRⅡB,SHP-1 and c-Src in the drug-containing serum+FcγRⅡB OE group were significantly increased(P<0.01),and the protein expression levels of LC3Ⅱ/Ⅰ were significantly decreased(P<0.01).Conclusion Liuwei Dihuangwan improved AD by inhibiting microglia FcγRⅡB/c-Src pathway and increasing autophagy level.

Objective:To explore drug detoxification motivation in methamphetamine-dependent female youth and its relationship with time perspective,perceived social support and emotion regulation strategies.Methods:To-tally 200 methamphetamine-dependent female youths under compulsory isolation were assessed with the Drug De-toxification Motivation Scale,Zimbardo Time Perspective Inventory-Chinese(ZTPI-C),Emotion Regulation Scale(ERS),and Perceived Social Support Scale(PSSS).Results:Multiple linear regression analysis showed that drug detoxification motivation scores were positively correlated with the scores of ERS reevaluation and expression inhi-bition,PSSS family support scores and level of education(β=0.24,0.16,0.20,0.16).Conclusion:Time perspec-tive,perceived social support and emotion regulation strategies are closely related to drug detoxification motivation in methamphetamine-dependent female youth.

Objective To study the effect of Liuwei Dihuangwan on autophagy level and its mechanism in SAMP8 mice and Aβ-stimulated BV2 cell model,and to explore the molecular mechanism of tonifying the kidney and filling up the essence to prevent and control Alzheimer's disease(AD)through interfering with autophagy.Methods Ten 7-month-old male anti-aging mice(SAMR1)were taken as the normal group,and 40 7-month-old male rapid aging mice(SAMP8)were randomly control and model groups,equal volumes of saline were administered by gavage twice a day for 4 weeks,and the levels of Aβ expression in the hippocampus of the mice in each group were detected by immunofluorescence;The expression levels of FcγRⅡB,c-Src and SHP-1 in the hippocampus of each group were detected by Western blot;BV2 cells were cultured and Fcγ receptor Ⅱ-b(FcγRⅡB)overexpression vectors were constructed;the AD state cell model was established by treating the BV2 cells with 5 μmol·L-1 Aβ1-42,and the Liuwei Dihuangwan drug-containing serum was prepared.The cells were divided into NC group,Aβ1-42 group,blank serum group,drug-containing serum group,Vector group,FcγRⅡB OE group,and drug-containing serum+FcγRⅡB OE group;immunofluorescence was used to detect the expression level of Aβ protein in the cells of each group;Western blot was used to detect the expression level of p62,LC3 Ⅱ/Ⅰ,FcγRⅡB,SHP-1,and c-Src in cells of each group.Results Compared with the normal group,the hippocampal Aβ,FcγRⅡB,SHP-1,and c-Src expression levels in the model group of mice were significantly higher(P<0.01),and compared with the model group,the expression levels of Aβ,FcγRⅡB,SHP-1,and c-Src in the low-,medium-,and high-dose groups of Liuwei Dihuangwan were significantly lower(P<0.01),it also showed a significant dose dependent relationship.Compared with NC group,the protein expressions of Aβ,p62,FcγRⅡB,SHP-1 and c-Src in Aβ1-42 group were significantly increased(P<0.01),and LC3Ⅱ/Ⅰ was significantly decreased(P<0.01);Compared with Aβ1-42 group and blank serum group,the protein expressions of Aβ,p62,FcγRⅡB,SHP-1 and c-Src in drug-containing serum group were significantly decreased(P<0.01),and LC3Ⅱ/Ⅰ was significantly increased(P<0.01);Compared with NC group and Vector group,the expression of Aβ in FcγRⅡB OE group was increased,the protein expressions of p62,FcγRⅡB,SHP-1 and c-Src were significantly increased(P<0.01),and LC3Ⅱ/Ⅰ was significantly decreased(P<0.01);Compared with the drug-containing serum group,the protein expressions of Aβ,p62,FcγRⅡB,SHP-1 and c-Src in the drug-containing serum+FcγRⅡB OE group were significantly increased(P<0.01),and the protein expression levels of LC3Ⅱ/Ⅰ were significantly decreased(P<0.01).Conclusion Liuwei Dihuangwan improved AD by inhibiting microglia FcγRⅡB/c-Src pathway and increasing autophagy level.

Objective:To explore drug detoxification motivation in methamphetamine-dependent female youth and its relationship with time perspective,perceived social support and emotion regulation strategies.Methods:To-tally 200 methamphetamine-dependent female youths under compulsory isolation were assessed with the Drug De-toxification Motivation Scale,Zimbardo Time Perspective Inventory-Chinese(ZTPI-C),Emotion Regulation Scale(ERS),and Perceived Social Support Scale(PSSS).Results:Multiple linear regression analysis showed that drug detoxification motivation scores were positively correlated with the scores of ERS reevaluation and expression inhi-bition,PSSS family support scores and level of education(β=0.24,0.16,0.20,0.16).Conclusion:Time perspec-tive,perceived social support and emotion regulation strategies are closely related to drug detoxification motivation in methamphetamine-dependent female youth.

Objective:To explore the relationship between relapse tendency and childhood maltreatment in methamphetamine-dependent youths,and the role of impulsivity and quality of life in the relationship.Methods:To-tally 287 methamphetamine-dependent youths(160 females,127 males)were selected in compulsory drug rehabili-tation centers.The Relapse Tendency Questionnaire(RTQ),Childhood Trauma Questionnaire-Short Form(CTQ-SF),Barrett Impulsivity Scale(BIS-11)and Quality of Life for Drug Addicts(QOL-DA)for Drug Addicts were used to conduct the survey.SPSS macro program PROCESS was used to test the mediating role.Results:The BIS-11 total scores acted as a partial mediator between the total scores of CTQ-SF and RTQ,with an effect value of 0.03(95％CI:0.01-0.05),the QOL-DA total scores acted as a full mediator between the total scores of CTQ-SF and RTQ,with an effect value of 0.05(95％CI:0.02-0.08),and the scores of BIS-11 and QOL-DA acted as chain mediators between total scores of CTQ-SF and RTQ,with an effect value of 0.01(95％CI:0.00-0.03).Conclusion:Childhood maltreatment,impulsivity,and quality of life may be associated with relapse tendencies in methamphetamine-dependent youths.

Objective To develop a highly sensitive and rapid nucleic acid detection method for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Methods We designed,developed,and manufactured an integrated disposable device for SARS-CoV-2 nucleic acid extraction and detection.The precision of the liquid transfer and temperature control was tested.A comparison between our device and a commercial kit for SARS-Cov-2 nucleic acid extraction was performed using real-time fluorescence reverse transcription polymerase chain reaction(RT-PCR).The entire process,from SARS-CoV-2 nucleic acid extraction to amplification,was evaluated. Results The precision of the syringe transfer volume was 19.2±1.9 μL(set value was 20),32.2±1.6(set value was 30),and 57.2±3.5(set value was 60).Temperature control in the amplification tube was measured at 60.0±0.0 ℃(set value was 60)and 95.1±0.2 ℃(set value was 95)respectively.SARS-Cov-2 nucleic acid extraction yield through the device was 7.10×106 copies/mL,while a commercial kit yielded 2.98×106 copies/mL.The mean time to complete the entire assay,from SARS-CoV-2 nucleic acid extraction to amplification detection,was 36 min and 45 s.The detection limit for SARS-CoV-2 nucleic acid was 250 copies/mL. Conclusion The integrated disposable devices may be used for SARS-CoV-2 Point-of-Care test(POCT).

Objective:This study aimed to develop a rapid and accurate integrated nucleic acid detection method tailored for the influenza virus.Methods:We designed primers and probes targeting the predominant influenza virus strains circulating in China in recent years. These were integrated with extraction and amplification reagents and a point of care testing (POCT) system to facilitate a seamless and expedited process involving nucleic acid extraction, reaction system preparation, amplification, and result interpretation for the influenza virus. The specificity of the POCT system was evaluated using cultured influenza viruses, while its cross-reactivity was assessed against common respiratory pathogens, including adenovirus and respiratory syncytial virus.Results:Our study successfully developed duplex amplification primers and probes for both influenza A and B viruses, achieving a detection threshold as low as 500 copies/ml. Specificity tests confirmed that the detection reagents did not show cross-reactivity with other respiratory pathogens such as adenovirus and respiratory syncytial virus. The POCT-based rapid nucleic acid detection method for influenza virus was established, it is capable of completing the entire process from nucleic acid extraction to amplification and result interpretation within 50 minutes, while enabling real-time data upload.Conclusions:The POCT-based rapid influenza virus detection kit developed in this study offers a " sample in, results out" convenience, making it suitable for rapid influenza virus detection in primary care settings. This innovation has significant potential for clinical application.

Objective:To investigate the effect of tripartite motif-containing protein 59 (TRIM59) on glucose metabolism in macrophages and its role in regulating hypoxia-inducible factor-1α (HIF-1α)/IL-10 axis in macrophages under inflammatory conditions.Methods:The differentially expressed genes between macrophages with high expression of TRIM59 and control cells transfected with empty TRIM59 plasmid were analyzed by GO and KEGG. The expression of HIF-1α by RAW264.7 macrophages with high expression of TRIM59 was detected at different time points after lipopolysaccharide (LPS) stimulation by RT-qPCR and Western blot. Bone marrow was isolated from TRIM59-cKO and TRIM59 flox/flox mice and induced to differentiate into bone marrow-derived macrophages (BMDMs). These BMDMs were stimulated with LPS and the supernatants of cell culture were collected at 3, 6, 12 and 24 h after stimulation to detect IL-10 level by ELISA. In addition, mouse models of cecal ligation and puncture (CLP) were established, and bronchoalveolar lavage fluid (BALF) samples were collected at the same time points to detect IL-10 level by ELISA. Histopathological changes in lung tissues were observed after HE staining. Results:There was a significant change in glucose metabolism-related genes in macrophages with high expression of TRIM59, and the content of lactic acid increased significantly. Compared with the control group, the expression of HIF-1α at mRNA level in BMDMs from TRIM59-cKO mice decreased after LPS stimulation ( P<0.05); the level of IL-10 increased at 3 h and 24 h in the TRIM59-cKO group, but there was no significant difference in IL-10 level at 6 h or 12 h between the two groups. In the TRIM59-cKO mouse model of CLP, the levels of IL-10 in the BALF samples increased with time, but decreased at 24 h. The level of IL-10 was higher in the TRIM59-cKO mouse model group than that in the control group at each time point ( P<0.05 or P<0.01). Conclusions:TRIM59 can inhibit inflammation and lung injury by decreasing HIF-1α-mediated lactate secretion and IL-10 expression in macrophages. This study provides a new idea for developing novel anti-sepsis drugs based on TRIM59.