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.

Objective To establish a stable,reliable,and clinically relevant porcine model of endotoxin-induced acute respiratory distress syndrome(ARDS).Methods Ten 8-month-old male Bama minipigs were deeply sedated,followed by invasive mechanical ventilation and electrocardiographic monitoring.Lipopolysaccharide(LPS)was intravenously pumped at 600 μg/(kg·h)for 3 hours,then maintained at 15 μg/(kg·h)thereafter.Dynamic monitoring was performed at five time points after LPS injection(LPS 0,1,3,5,and 8 h),including arterial blood gas analysis and chest computed tomography(CT)scans.Pathological examination of lung tissues obtained via bronchoscopic biopsy(HE staining and transmission electron microscopy)was conducted.These indicators were comprehensively used to evaluate the success of the animal model.Results At 5 hours after LPS administration,8 minipigs developed symptoms such as skin cyanosis,elevated body temperature,and respiratory distress.The oxygenation index decreased to<300 mmHg.Chest CT scans showed diffuse pulmonary infiltrates.Histopathology revealed alveolar edema and hyaline membrane formation.Transmission electron microscopy demonstrated disruption of pulmonary blood-air barrier,depletion of lamellar bodies in type Ⅱ pneumocytes,inflammatory cell infiltration,and exudation of plasma proteins and fibrin.Compared with LPS 0 h,at LPS 8 h,the oxygenation index and arterial blood pH were significantly decreased(P<0.001),while blood lactic acid and serum potassium were significantly increased(P<0.05);serum calcium and base excess were significantly decreased(P<0.05),and the lung injury score based on HE-stained lung sections was significantly increased(P<0.01).Conclusion The porcine ARDS model established by continuous LPS injection can dynamically simulate the pathophysiological characteristics and typical pathological manifestations of clinical septic ARDS,making it an effective tool to study the pathogenesis,prevention,and treatment strategies of septic ARDS.

OBJECTIVE: Photodynamic therapy has become an important method in clinical tumor treatment. This study aimed to investigate the effects of hematoporphyrin on multiple myeloma (MM) and its potential applications. METHODS: The MM cell line RPMI 8226 was treated with hematoporphyrin derivative (HPD), and CCK-8 assay was used to determine cell viability, apoptosis was detected by flow cytometry, intracellular reactive oxygen species (ROS) levels were measured using a detection kit combined with flow cytometry, and Western blot assay was used to detect apoptosis-related proteins and key signaling pathway protein levels. RESULTS: The optimal incubation time for the maximum absorption of HPD in RPMI 8226 cells was 4 hours. HPD significantly inhibited the proliferation of RPMI 8226 cells in a dose- and illumination time-dependent manner ( r =0.981; r =0.961). Additionally, HPD induced apoptosis in RPMI 8226 cells, but had no significant inhibitory effect on peripheral blood mononuclear cells derived from healthy individuals. HPD combined with illumination treatment significantly increased the intracellular ROS level, upregulated the expression of apoptosis-related proteins such as cleaved PARP, cleaved caspase-3 and Bax, and down-regulated the expression of proteins that maintain cell survival, such as NF-κB and Akt. CONCLUSION The HPD can inhibit the proliferation and induce apoptosis of multiple myeloma cells.
Humans ; Multiple Myeloma/pathology* ; Hematoporphyrins/pharmacology* ; Apoptosis/drug effects* ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Cell Proliferation/drug effects* ; Photochemotherapy ; Cell Survival/drug effects* ; Signal Transduction

An implantable cardiac monitor(ICM)is a subcutaneous electronic device for recording and remotely transmitting electrocardiographic events.New-generation ICM,like the Reveal LINQ,have extended arrhythmia monitoring duration and improved diagnostic yield through miniaturization,large storage capacity,and easy implantation.They provide comprehensive monitoring data for cardiovascular disease diagnosis and treatment,optimize individualized treatment plans,and enhance patient prognosis.In recent years,research on ICM in cardiovascular fields has deepened,and their clinical application scope has expanded.They show significant advantages and unique value and are widely used in early cardiovascular disease diagnosis and prognostic management.In the future,ICM are expected to play a bigger role in boosting diagnostic and prognostic capabilities for cardiovascular disease patients,offering stronger support for early disease detection,accurate diagnosis,and effective management.

An implantable cardiac monitor(ICM)is a subcutaneous electronic device for recording and remotely transmitting electrocardiographic events.New-generation ICM,like the Reveal LINQ,have extended arrhythmia monitoring duration and improved diagnostic yield through miniaturization,large storage capacity,and easy implantation.They provide comprehensive monitoring data for cardiovascular disease diagnosis and treatment,optimize individualized treatment plans,and enhance patient prognosis.In recent years,research on ICM in cardiovascular fields has deepened,and their clinical application scope has expanded.They show significant advantages and unique value and are widely used in early cardiovascular disease diagnosis and prognostic management.In the future,ICM are expected to play a bigger role in boosting diagnostic and prognostic capabilities for cardiovascular disease patients,offering stronger support for early disease detection,accurate diagnosis,and effective management.

Background and aims Cancer cachexia is prevalent in various cancers and is associated with chemotherapy toxicity. However, limited data exist on the relationship between cachexia and immune-related adverse events (irAEs). The aim of this study is to explore the correlation between cancer cachexia and irAEs and its possible mechanism. Methods A murine model of orthotopic hepatocellular carcinoma (HCC) with cachexia was developed to evaluate the impact of T-cell infiltration into multiple tumor-free organs on the occurrence of irAEs. Single-cell RNA sequencing of thymic stromal cells was performed. Additionally, patients with advanced cancers receiving anti-programmed cell death protein 1/ligand 1 (PD-1/L1) antibody treatment were followed to investigate the relationship between cachexia and irAEs. Results Inflammatory cell infiltration was observed in multiple tumor-free organs of cachexic HCC mice but not in non-cachexic controls. Immunofluorescence confirmed that the infiltrating cells included CD4+ and CD8+ T cells. Morphological assessment and hematoxylin–eosin staining revealed thymic atrophy in cachexic HCC mice. Single-cell RNA sequencing of thymic stromal cells showed a reduction in medullary thymic epithelial cells (mTECs) II and III in cachexic mice. Autoimmune regulator (Aire) downregulation was accompanied by decreased expression of tissue-restricted antigens in mTECs. T cells from cachexic HCC mice induced organ-specific inflammation and T-cell infiltration in multiple organs of tumor-free mice. Following anti-mouse PD-1 antibody treatment, the incidence of inflammation in multiple organs markedly increased in cachexic HCC mice and in tumor-free mice that had received T cells from the cachexic HCC mice. Flow cytometry and immunofluorescence analyses revealed enrichment of thymic monocytic myeloid-derived suppressor cells (M-MDSCs) in cachexic HCC mice. M-MDSCs infiltrated the thymus in cachexic mice with cancer, and they induced apoptosis of mTECs from tumor-free mice in vitro via nitric oxide production. Transfer of M-MDSCs led to inflammatory cell infiltration in multiple organs and thymic involution in tumor-free mice without affecting body weight. Sixty-four patients with advanced cancer receiving anti-PD-1/L1 therapy were enrolled. Patients who developed irAEs had higher levels of circulating M-MDSCs than those who did not. Moreover, patients with cachexia (body mass index (BMI) < 20 kg/m2 or ≥5% weight loss over the past 6 months) had elevated M-MDSC levels. Patients with both high M-MDSC levels and low BMI or weight loss ≥5% experienced more irAEs (hazard ratio: 2.333; 95% confidence interval: 1.231–4.423). Conclusions M-MDSCs in cachexic mice induced mTEC apoptosis through nitric oxide production, impairing T-cell negative selection and promoting autoimmune T-cell infiltration into tumor-free organs. Cancer cachexia-related M-MDSCs may serve as predictive biomarkers for irAEs in patients with advanced cancer. Graphical abstract

Objective To summarize the epidemiological and clinical features of infectious diseases of the central nervous system(CNS)by a single-center analysis.Methods A retrospective analysis was conducted on the data of 1247 cases of CNS infectious diseases diagnosed and treated in the First Medical Center of PLA General Hospital from 2001 to 2020.Results The data for this group of CNS infectious diseases by disease type in descending order of number of cases were viruses 743(59.6％),Mycobacterium tuberculosis 249(20.0％),other bacteria 150(12.0％),fungi 68(5.5％),parasites 18(1.4％),Treponema pallidum 18(1.4％)and rickettsia 1(0.1％).The number of cases increased by 177 cases(33.1％)in the latter 10 years compared to the previous 10 years(P<0.05).No significant difference in seasonal distribution pattern of data between disease types(P>0.05).Male to female ratio is 1.87︰1,mostly under 60 years of age.Viruses are more likely to infect students,most often at university/college level and above,farmers are overrepresented among bacteria and Mycobacterium tuberculosis,and more infections of Treponema pallidum in workers.CNS infectious diseases are characterized by fever,headache and signs of meningeal irritation,with the adductor nerve being the more commonly involved cranial nerve.Matagenomic next-generation sequencing improves clinical diagnostic capabilities.The median hospital days for CNS infectious diseases are 18.00(11.00,27.00)and median hospital costs are ￥29,500(￥16,000,￥59,200).The mortality rate from CNS infectious diseases is 1.6％.Conclusions The incidence of CNS infectious diseases is increasing last ten years,with complex clinical presentation,severe symptoms and poor prognosis.Early and accurate diagnosis and standardized clinical treatment can significantly reduce the morbidity and mortality rate and ease the burden of disease.

Objective To investigate the implementation of surveillance,prevention and control measures for healthcare-associated infection(HAI)in maternal and child healthcare(MCH)institutions,and provide policy evi-dence for optimizing HAI prevention and control in MCH institutions.Methods Stratified sampling was conducted among the MCH institutions at provincial,municipal and county levels in 8 provinces/autonomous regions.A uni-fied questionnaire was designed and the online survey was conducted through"Questionnaire Star".Results The data from 123 MCH institutions were included in the analysis.90.24％of the MCH institutions carried out compre-hensive surveillance on HAI.The ratios of MCH institutions which implemented targeted surveillance on HAI in neonatal intensive care unit(NICU),surgical site infection,multidrug-resistant organisms(MDROs)and HAI in intensive care units(non-NICU excluded)were 89.66％,85.96％,80.77％,and 74.19％,respectively.51.22％MCH institutions adopted information surveillance system on HAI cases.94.31％MCH institutions carried out surveillance on hand hygiene compliance.Over 90％MCH institutions carried out surveillance on environment hy-giene in high-risk departments.71.54％MCH institutions conducted centralized cleaning,disinfection,sterilization and supply for reusable medical instruments in the central sterile supply department(CSSD).Over 90％MCH insti-tutions established three-level pre-examination triage systems.86.18％set up transitional wards.MCH institutions generally adopted a management model with established effective communication,full appointment visits,and sepa-rate visits for special medical groups,such as registered pregnant women,high-risk newborns,healthcare groups,and long-term rehabilitation patients.However,the ratio of institutions conducting on-line follow-up visits was less than 50％.Conclusion MCH institutions have generally carried out comprehensive and targeted surveillance on HAI.Information surveillance need to be facilitated.Hand hygiene and environmental hygiene surveillance has been popularized to a certain extent at all levels of MCH institutions.The cleaning,disinfection,sterilization,and supply processes of reusable medical devices in a few MCH institutions are not standardized.Special medical populations get effective management.On-line healthcare is to be further promoted.

Diabetes mellitus is a metabolic disease with high incidence and many complications,among which type 2 diabetes mellitus(T2DM)accounts for a large proportion.Current studies have shown that T2DM is accompanied by damage of liver,kidney,and other organs and its complications seriously en-danger human health.Ferroptosis generates many Reactive Oxygen Species(ROS)through the Fenton reaction,and the accumulation of ROS activates Hypoxia Inducible Factor-1(HIF-1α).As a result,the level of vascular endothelial growth factor(VEGF)is increased.Ferrostatin-1(Fer-1),a ferroptosis in-hibitor,has strong antioxidant capacity.Therefore,based on the hypoxia-inducible factor-1α/vascular endothelial growth factor(HIF-1α/VEGF)signaling pathway,we explored the therapeutic effect of Fer-1 on the liver and kidney tissues of diabetic mice.db/db mice(21～22 weeks old)were used as the model of diabetes mellitus.Ferroptosis inhibitor Fer-1 was used as the intervention drug.db/m mice served as the blank control group,and body weight and blood glucose were measured for 4 weeks.Food intake and water intake were recorded in each group.The levels of Alanine aminotransferase(ALT)and Aspartate aminotransferase(AST)in the serum were measured.ROS and Glutathione(GSH)activity in liver and kidney tissues and urinary protein content were measured.Liver and kidney tissue sections were stained with Hematoxylin-Eosin(HE),and the pathological morphology was observed under a light microscope.The protein levels of HIF-1α,VEGF,and glutathione peroxidase 4(GPX4)in liver and kidney tissues were detected by Western blot.In db/db mice,Fer-1(1 mg·kg-1,ig)could significantly reduce the a-mount of food and water intake,the levels of ALT and AST in serum,the ROS production in liver and kidney tissues,and the level of urine protein,but significantly increase the activity of GSH,thus improve the pathological conditions of liver and kidney.Fer-1 also significantly inhibited HIF-1α and VEGF pro-tein indexes and increased GPX4 protein levels in liver and kidney tissues.Although Fer-1 can not change the body weight and reduce blood glucose in diabetic mice,it can play a therapeutic role in the liver and kidney tissues of diabetic mice in the middle and late stages,and its mechanism may be related to HIF-1α/VEGF and GPX4.

Objective:To investigate two cases of rare pathogenic genes,initiation codon mutations in HBA2 gene,combined with Southeast Asian deletion and their family members to understand the relationship of HBA2:c.2T＞C and HBA2:c.2delT mutations with clinical phenotype.Methods:The peripheral blood of family members was obtained for blood cell analysis and capillary electrophoresis hemoglobin analysis.Gap-PCR and reverse dot blotting(RDB)were used to detect common types of mutations in α-thalassaemia gene.Sanger sequencing was used to analyze HBA1 and HBA2 gene sequence.Results:Two proband genotypes were identified as--SEA/αα with HBA2:c.2T＞C and--SEA/αα with HBA2:c.2delT.HBA2:c.2T＞C/WT and HBA2:c.2delT/WT was detected in family members.They all presented with microcytic hypochromic anemia.Conclusion:When HBA2:c.2T＞C and HBA2:c.2delT are heterozygous that can lead to static α-thalassemia phenotype,and when combined with mild α-thalassemia,they can lead to the clinical manifestations of hemoglobin H disease.This study provides a basis for genetic counseling.