Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.

Humans ; PPAR gamma/metabolism* ; Multiple Sclerosis ; Transcription Factors/metabolism* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha

In this study, fluvoxamine maleate sustained-release pellet system tablets were prepared and were used to evaluate their release behaviors in vitro. Fluvoxamine maleate pellets were prepared using centrifugal-spherization method and coated by fluidized bed as bottom-spray. The multi-unit sustained-release pellets and appropriate excipients for prescription volumes were mixed uniformly and then compressed to tablets. Screening and determining the optimal formulation of drug loaded pellets through L8 (2⁴) Taguchi experiment. Using Minitab software to design a DOE experiment with 2⁴ partial factors, including material temperature, fan speed, atomization pressure, and spray rate to optimize the bottom spray coating process. Taking monostearate glycerol ester with a particle size of 24-40 mesh as the main diluent for tableting to relieve the delamination phenomenon between pellets and excipients during tablet pressing and reduce mechanical damage to the coating film. By examining the powder fluidity indexes such as angle of repose, bulk density, tapped density, and Hausner ratio of mixed particles, it was found that the flowability and compressibility are good and suitable for direct compression. Evaluate the basic properties of the sustained-release tablets, investigate the in vitro release behavior and study the release mechanism. The results of in vitro release test showed that the self-made sustained-release tablets could disintegrate into independent pellet units in phosphate buffer at pH 6.8 and release slowly within 24 h, which conformed to the first-order drug release model. The fluvoxamine maleate sustained-release pellet system tablets meet the requirements of preparation design and has a great commercial prospect.

Objective:To analysis the job preference and heterogeneity of medical students by distinguishing their birthplaces,and to provide reference for optimizing the management of primary health care resources.Methods:Using a cluster sampling method,an online survey of discrete choice experiment was conducted with 925 medical students from six teaching hospitals in Beijing,741 valid questionnaires were obtained,the effective recovery rate was 80.1%.The mixed logit model was used to perform regression analysis on six job attributes and estimate the willingness to pay.Results:There were significant differences in the choice of work location among medical students from different birthplaces.The subgroup results showed that compared to medical students from city,undergraduates from rural and county district preferred a work with sufficient career development opportunities.The results of undergraduate subgroup showed that undergraduates from rural district preferred a work with good environment than those from other birthplaces.Conclusion:There is heterogeneity in job preferences of medical students from different birthplaces.Policy makers should pay attention to the medical students'birthplace,also take the educational level into account to optimize the diversified job attributes,formulating targeted intervention to attract primary health care talents.

Acute kidney injury (AKI) is a devastating complications of end-stage of liver disease (ESLD), seriously affecting the prognosis of patients. With the deepening understanding of the pathogenesis, the definition, staging, diagnosis and treatment of ESLD with AKI have been gradually optimized. This article reviews the evolution of definition, pathogenesis, diagnosis and treatment of ESLD with AKI, to provide reference for early recognition, precise diagnosis and standardized treatment of this condition.

Objective:To investigate the correlation factors of complete clinical response in idiopathic inflammatory myopathies(IIMs)patients receiving conventional treatment.Methods:Patients diagnosed with IIMs hospitalized in Peking University People's Hospital from January 2000 to June 2023 were in-cluded.The correlation factors of complete clinical response to conventional treatment were identified by analyzing the clinical characteristics,laboratory features,peripheral blood lymphocytes,immunological indicators,and therapeutic drugs.Results:Among the 635 patients included,518 patients finished the follow-up,with an average time of 36.8 months.The total complete clinical response rate of IIMs was 50.0％(259/518).The complete clinical response rate of dermatomyositis(DM),anti-synthetase syn-drome(ASS)and immune-mediated necrotizing myopathy(IMNM)were 53.5％,48.9％and 39.0％,respectively.Fever(P=0.002)and rapid progressive interstitial lung disease(RP-ILD)(P=0.014)were observed much more frequently in non-complete clinical response group than in complete clinical re-sponse group.The aspartate transaminase(AST),lactate dehydrogenase(LDH),D-dimer,erythrocyte sedimentation rate(ESR),C-reaction protein(CRP)and serum ferritin were significantly higher in non-complete clinical response group as compared with complete clinical response group.As for the treat-ment,the percentage of glucocorticoid received and intravenous immunoglobin(IVIG)were significantly higher in non-complete clinical response group than in complete clinical response group.Risk factor analysis showed that IMNM subtype(P=0.007),interstitial lung disease(ILD)(P=0.001),eleva-ted AST(P=0.012),elevated serum ferritin(P=0.016)and decreased count of CD4+T cells in peripheral blood(P=0.004)might be the risk factors for IIMs non-complete clinical response.Conclu-sion:The total complete clinical response rate of IIMs is low,especially for IMNM subtype.More effec-tive intervention should be administered to patients with ILD,elevated AST,elevated serum ferritin or decreased count of CD4+T cells at disease onset.

Objective:To assess the current situation, advantages, and difficulties of standardized management in Investigator-Initiated Clinical Trials (IIT).Methods:This article summarized the requirements and policies for clinical research management, the development of clinical research domestically and internationally, the achievements and advantages of clinical research management development in China, and the main problems and difficulties with the standardized IIT management in China, and compiled the experiences and models of several medical institutions in IIT management.Results:While China has a large number of clinical medical publications and is ranked high in the world, the quality of the publications needs to be further improved. Domestic management requirements for IIT were gradually improving, providing a basis for medical institutions to implement standardized management throughout the lifecycle of IIT, and achieve certain progress. However, there were still challenges in the departmental divisions, the unification of management standards, whole-process management and quality control, the scientific review, high-risk project management, and registration.Conclusions:Drawing on the excellent experience of domestic medical institutions, measures including identifying a primary responsible department, establishing unified supervision and inspection standards, and implementing a whole life cycle management may help overcome the challenges in IIT management and improve the quality and efficiency of IIT management.

Objective To investigate the mechanism through which RgpB,a virulence factor of Porphyromonas gingivalis(Pg),induces chemoresistance in esophageal squamous carcinoma.Methods The autophagy-regulating factors that interact with RgpB were screened by immunoprecipitation-mass spectrometry.The interaction between RgpB and the autophagy regulator TBC1D5 was investigated using co-immunoprecipitation.The impact of Pg infection on the expression of esophageal cancer cell membrane receptor molecule Cx43 was assessed using Western blotting.Immunofluorescence assay was used to analyze the relationship among Lamp1,Cx43 and TBC1D5.The effect of Pg infection on autophagosome-lysosome fusion was evaluated using autophagy double fluorescence technique.The effects of Pg infection and a Cx43 inhibitor on proliferation of esophageal cancer cells after chemotherapy were examined with plate cloning assay and CCK-8 method.Results Immunoprecipitation-mass spectrometry identified TBC1D5 as an autophagy regulator interacting with RgpB,and co-immunoprecipitation suggested that RgpB could directly bind to TBC1D5.In Pg-infected esophageal cancer cells,the expression of Cx43 on the cell membrane was significantly higher than that in non-infected cells.Immunofluorescence assay showed that the expression of Cx43 on the membrane of esophageal cancer cells increased significantly after Pg infection,which blocked autophagosome-lysosome fusion as shown by stubRFP-sensGFP-LC3 lentivirus study.Plate cloning assay and CCK-8 assay showed that the Cx43 inhibitor significantly attenuated the effect of Pg infection for promoting proliferation of esophageal cancer cells after chemotherapy.Conclusion Pg infection in esophageal cancer blocked autophagosome-lysosome fusion in the tumor cells,thereby preventing Cx43 from lysosomal degradation and leading to chemoresistance of esophageal cancer.

Objective To investigate the effects of zalcitabine(ddC),a mitochondrial DNA polymerase γ(POLG)inhibitor,on the migration,invasion,and to preliminarily explore mitochondrial biogenesis of human tri-ple-negative breast cancer MDA-MB-231 cells.Methods The effect of ddC on cell viability was detected using the MTT assay.The migration and invasion abilities of the cells were evaluated using the cell scratch and Transwell in-vasion assays.Cell apoptosis was determined using flow cytometry and a V-FITC/PI cell apoptosis detection kit.The protein expression of POLG,NADH dehydrogenase subunit Ⅰ(NADH1),NADH dehydrogenase subunit Ⅱ(NADH2),ATP synthase subunit 6(ATPase6),cytochrome c oxidase subunit Ⅰ(COX-1)and cytochrome c ox-idase subunit Ⅲ(COX-3)were determined using Western blot.The POLG mRNA level and mtDNA copy number were determined using qPCR.The mitochondrial content and ATP levels were determined using MitoTracker Green fluorescent probe staining and an ATP determination kit.MDA-MB-231 cells were transfected with pcDNA3.1-EG-FP-POLG plasmids to overexpress POLG.The inhibitory effects of ddC on cell migration and invasion were detected in POLG-overexpressed MDA-MB-231 cells.Results POLG expression was higher in MDA-MB-231 cells than in normal mammary epithelial cells(MCF-10A)(P＜0.01).ddC inhibited cell viability in a dose-dependent man-ner.ddC inhibited the migration(P＜0.01)and invasion(P＜0.01)of MDA-MB-231 cells;however,it dis-played no significant inhibitory effects on cell viability in normal mammary epithelial cells(MCF-10A)at the same concentration.ddC downregulated the protein(P＜0.01)and mRNA(P＜0.01)levels of POLG,reduced mtD-NA copy number(P＜0.01)and downregulated mtDNA-coded NADH1,NADH2,ATPase6,COX-1 and COX-3 protein expression(P＜0.01)in MDA-MB-231 cells.Furthermore ddC inhibited mitochondrial content(P＜0.01)and ATP(P＜0.01)levels in MDA-MB-231 cells.POLG overexpression increased the migration(P＜0.05)and invasion(P＜0.05)abilities of MDA-MB-231 cells,while ddC did not significantly inhibit the migra-tion and invasion abilities of MDA-MB-231 cells overexpressing POLG.Conclusion ddC downregulates POLG ex-pression in MDA-MB-231 cells and inhibits mitochondrial biogenesis and ATP levels,thereby inhibiting the migra-tion and invasion of MDA-MB-231 cells.

Objective To investigate the efficacy and safety of camrelizumab monoclonal antibody combined with molecular-targeted therapy in elderly patients with unresectable or advanced hepatocellular carcinoma(HCC).Methods A retrospective analysis was performed for the patients with unresectable/advanced HCC who attended six hospitals from January 1,2019 to March 31,2021,and all patients received camrelizumab monoclonal antibody treatment,among whom 84.8%also received targeted therapy.According to the age of the patients,they were divided into elderly group(≥65 years)and non-elderly group(＜65 years).The two groups were assessed in terms of overall survival(OS),progression-free survival(PFS),objective response rate(ORR),disease control rate(DCR),and immune-related adverse events(irAE).The chi-square test or the Fisher's exact test was used for comparison of categorical data between groups;the independent samples t-test was used for comparison of normally distributed continuous data,and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups.The Kaplan-Meier method was used for survival analysis,and the log-rank test was used for comparison of survival curves.Univariate and multivariate Cox proportional hazards regression analyses were used to determine the independent influencing factors for PFS and DCR at 6 months.Results A total of 99 HCC patients were enrolled,with 27 in the elderly group and 72 in the non-elderly group.The elderly group had an OS rate of 67.8%,an ORR of 44.4%,and a DCR of 74.1%at 12 months and a median PFS of 6.4(95%confidence interval[CI]:3.0-12.4)months,with no significant differences compared with the non-elderly group(all P＞0.05).The median OS was unavailable for the elderly group,while the non-elderly group had an OS of 18.9(95%CI:13.0-24.8)months;there was no significant difference between the two groups(P=0.485).The univariate and multivariate Cox regression analyses showed that major vascular invasion(MVI)was an independent risk factor for PFS(hazard ratio[HR]=2.603,95%CI:1.136-5.964,P=0.024)and DCR(HR=3.963,95%CI:1.671-9.397,P=0.002)at 6 months,while age,sex,etiology of HBV infection,presence of extrahepatic metastasis,Child-Pugh class B,and alpha-fetoprotein＞400 ng/mL were not associated with PFS or DCR at 6 months.For the elderly group,the incidence rates of any irAE and grade 3/4 irAE were 51.9%and 25.9%,respectively,with no significant differences compared with the non-elderly group(P＞0.05),and skin disease was the most common irAE in both groups(39.4%).Conclusion Camrelizumab monoclonal antibody combined with molecular-targeted therapy has similar efficacy and safety in patients with unresectable/advanced HCC aged≥65 years and those aged＜65 years.MVI is associated with suboptimal response to immunotherapy and poor prognosis.