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.

Aim To investigate the protective effects of Tilianin on lipopolysaccharide(LPS)-induced septice-mia-induced myocardial injury in rats and to explore the related mechanisms.Methods Animals were ran-domly grouped and a rat septicemia-induced myocardial injury model was constructed.Echocardiography was used to assess the cardiac function of rats,left ventricu-lar internal diameter at end-diastole(LVIDd)and left ventricular internal diameter at end-systole(LVIDs)were measured,and left ventricular ejection fraction(LVEF)and left ventricular fractional shortening(LVFS)were calculated;the kits were used to detect the serum activity of the relevant cardiac enzymes and the level of inflammatory factors;HE staining was used to observe the morphological changes of myocardium;immunofluorescence staining of cardiac tissues was used to detect the nuclear translocation of NF-κB p65;Western blot was used to detect the expression of TLR4,MyD88,p-NF-κB p65,and NLRP3 proteins in cardiac tissues.Results Compared with the model group,each administration group differently upregulated LVEF,LVFS,and LVIDs,and improved the coordina-tion of LV wall fluctuations in the model group of rats;cardiac enzymes LDH and CK-MB levels increased,and levels of inflammatory factors TNF-α,IL-6,and IL-1 β were reduced,exerting cardioprotective effects;HE staining showed that myocardial tissue cell gap was re-duced,myocardial fiber breakage was reduced,cardio-myocyte arrangement tended to be normal,and inflam-matory cell infiltration was reduced;NF-κB p65 entry into the nucleus was reduced,and phosphorylated NF-κB p65(p-NF-κB p65)expression was reduced;and Western blot results showed that the expression of TLR4,MyD88,and NLRP3 proteins was reduced.Conclusions Tilianin pretreatment reduces serum my-ocardial enzymes and inflammatory factors and im-proves myocardial injury in rats with septicemia-in-duced myocardial injury,which may be related to the Tilianin anti-TLR4/NF-κB/NLRP3 inflammatory signa-ling pathway.

This study aims to investigate the epidemic variation of porcine circovirus type2(PCV2)and its distribution in swine farms in Henan Province from 2022 to 2023.In this study,1 206 pig blood samples from 18 urban scale swine farms,and 318 pigs and environmental samples from 2 PCV2-positive swine farms in Henan Province were detected by fluorescence quantitative PCR.ORF2 gene sequencing and genetic evolution analysis were performed on the positive samples.The results showed that the positive rate of PCV2 was 7.05％(85/1 206)in Henan Province,11.15％in western Henan Province and 3.03％in southern Henan Province.The positive rate of PCV2 in spring was 11.60％(67/576).A total of 31 ORF2 gene sequences were obtained,of which 23 were PCV2d(74.19％),6 were PCV2a(19.35％),one was PCV2b(3.23％)and one was PCV2c(3.23％).The results of amino acid sequence comparison showed that the mutation sites mainly concentrated on amino acids at positions 40-68 and 180-209.The total positive rate of pig farm sam-ples was 37.42％(119/318),and the positive rate of pig samples from different types of pig houses was 60.71％(34/56),45.83％(11/24),35.09％(20/57),and 33.33(3/9)in order from high to low.The positive rate of environmental samples from high to low was 56.36％(31/55)in feeding system,46.67％(7/15)in feces system,12.50(1/8)in decontamination area,11.11％(2/18)in living area,and no PCV2 was detected in ventilation system.The highest positive rate was 45.00％(9/20)for the tools in the house,7.14％(1/14)for the surface and sole of the clothes after leaving the house,and no PCV2 was detected on the surface and sole of the clothes before entering the house.In this study,the epidemiological investigation of PCV2 in Henan Province and its distribu-tion in swine farms were carried out,and the main circulating strains,seasons,regions and gene mutations of PCV2 in H enan Province were identified.The distribution and transmission routes of PCV2 in positive pig farms were preliminarily analyzed and summarized,which provided data basis and reference for effective prevention and control of PCV and the establishment of accurate bio-safety prevention and control measures.

Objective:To discuss the role of changes of serum total bile acid(TBA)levels induced by long-term high-fat diet in the occurrence of supraventricular arrhythmia(SVA)in the apolipoprotein E knockout(ApoE-/-)mice,and to clarify its mechanism.Methods:Twenty ApoE-/-mice were randomly divided into normal diet group and high-fat diet(HFD)group(n=10);after 20 weeks of feeding,surface electrocardiogram was used to detect cardiac electrophysiology of the mice in various groups;echocardiography was used to detect cardiac systolic function and structure in the mice in various groups;enzyme-linked immunosorbent assay(ELISA)was used to detect serum levels of blood lipids,total bile acid(TBA)and inflammatory factors in the mice in various groups;hematoxylin-eosin(HE)staining was used to detect cardiac inflammatory response in the mice in various groups;Masson staining was used to observe myocardial fibrosis degree in the mice in various groups.Results:Compared with normal diet group,4 cases of junctional premature beat(JPB)/junctional tachycardia(JT),1 case of premature atrial contraction(PAC)and 1 case of premature ventricular contraction(PVC)were found in HFD group,while only 1 case of JPB/JT and 1 case of PAC were found in normal diet group.Compared with normal diet group,the heart rate of the mice in HFD group was significantly decreased(P<0.05);the QRS and QT intervals were significantly prolonged(P<0.05);the ejection fraction(EF)and fractional shortening(FS)were significantly decreased(P<0.05);the end-diastolic volume(EDV)was increased(P<0.05),but there was no significant difference in end-systolic volume(ESV)between groups(P>0.05);the left ventricular internal diameter at end-diastole(LVIDd)and left ventricular internal diameter at end-systole(LVIDs)were significantly increased(P<0.05).There were no significant differences in plasma total cholesterol(TC),triglyceride(TG),high-density lipoprotein(HDL-c)and low-density lipoprotein(LDL-c)levels and body weight between normal diet group and HFD group(P>0.05).Compared with normal diet group,the TBA level of the mice in HFD group was significantly increased(P<0.05).There were no significant differences in interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),monocyte chemoattractant protein-1(MCP-1),and C-X-C motif chemokine ligand 1(CXCL-1)levels between HFD group and normal diet group.Compared with normal diet group,the interleukin-1β(IL-1β)level in HFD group showed an increasing trend,but there was no significant difference between groups(P>0.05).The HE staining results showed that the inflammatory cell infiltration was similar between HFD group and normal diet group.The Masson staining results showed that compared with normal diet group,the fibrosis of the mice in HFD group showed an increasing trend,but there was no significant difference in myocardial fibrosis area between groups(P>0.05).Conclusion:Long-term high-fat diet may increase serum TBA level in ApoE-/-mice,which may induce SVA.

Objective To improve and refine the relevant regulations and guiding principles of warnings on drug instructions and labels in China.Methods This paper sorted out the drug instructions of small molecule anti-tumor drugs listed by the U.S.Food and Drug Administration(FDA)from 2005 to 2022,included the drugs mentioned in the QT interval prolongation risk,analyzed the clinical research and QT research results,and sorted out the identification and warning rules of the instructions.Results A total of 35 drugs were included,4 drugs wrote the risk of QT interval prolongation in the black box warning,21 drugs were wrote in the warning and precautions position,6 drugs were wrote in the adverse reaction section,and 2 drugs were only described under clinical pharmacology section.According to the severity of the QT interval prolongation caused by the drug and whether there were serious clinical consequences,they were displayed in the warnings(black box warnings),precautions(warnings and precautions)and adverse reactions in the instructions.Conclusion The aim of this article is to provide a reference for the writing of QT risk warning information of the instructions of domestic drug production enterprises and regulatory departments.It is recommended to clarify the severity of drug safety and the location of the instructions in clinical research,and continue to carry out safety monitoring and update the instructions in time after listing.

Objective:To understand the current situation and the relevant factors of the intrinsic capacity of the elderly in nursing institutions.Methods:It was a cross-sectional study. From December 2023 to February 2024, a total of 10 elderly people living in 5 institutions in Huaihua City, Hunan Province, 3 institutions in Changsha City, and 2 institutions in Yinchuan City, Ningxia Hui Autonomous Region, were conveniently selected. Relevant clinical data of the participants were collected through questionnaires. The 5 dimensions of motor, psychological, cognitive, vitality, and perceptual were selected to evaluate the intrinsic capacity of the participants, and their total intrinsic capacity scores were calculated by using the Short Physical Performance Battery, Geriatric Depression Scale, Mini-mental State Examination, Short-Form Mini-Nutritionalas Assessment and the Complaints Sensory Functioning, respectively. Multiple linear stepwise regression models were used to analyze the correlates of intrinsic competence in older adults in nursing facilities.Results:Two hundred and seventy institutionalized older adults were included in the analysis, aged (80.9±8.5) years, 117(43.33%) were male, and the length of residence in an institution was 1.50(0.83, 3.00) years.The intrinsic capacity score of the 270 institutionalized older adults was 2.24±0.97, of which 265(98.15%) had declining intrinsic capacity and 5(1.85%) had good intrinsic capacity. The results of multiple linear stepwise regression analysis showed that literacy level, economic source, occupation, frequency of exercise, use of smartphones, use of elderly mobility aids, and whether or not the elderly living in the nursing home received financial support from the state were independently associated with the intrinsic ability of the elderly living in the nursing home (all P<0.05). Conclusions:The overall level of intrinsic capacity of the investigated elderly in nursing homes is low, and literacy level, economic source, occupation, use of smartphones, use of elderly mobility aids, and whether the nursing home receives state financial support are independent correlates of the intrinsic ability of the elderly in nursing homes.

BACKGROUND:The asymmetrical biomechanical environment of adolescent idiopathic scoliosis can lead to further wedge deformation of the vertebral body,which may affect cardiopulmonary function and compress nerves in severe cases.Adolescent idiopathic scoliosis with different degrees of scoliosis should be treated with exercise,bracing,and surgery.However,the mechanical mechanism of selecting an orthopedic approach remains unclear due to the individual variability of patients.OBJECTIVE:To investigate the biomechanical mechanism of different orthopedic modalities for the treatment of adolescent idiopathic scoliosis to provide a basis for clinical selection of treatment modalities based on the spine model of adolescent idiopathic scoliosis patients.METHODS:Based on the CT images of an adolescent idiopathic scoliosis patient,a scoliosis model(C7-L5)was reconstructed in Mimics software in three dimensions,and lateral thrust force was applied at the T8/T9 thorax and vertical distraction force was applied over the C7 vertebra with the magnitude of 20,40,60,80,100,and 120 N.The intervertebral disc stress and vertebral displacement in concave and convex sides,and Cobb angle of the spine were analyzed under two orthopedic modalities.RESULTS AND CONCLUSION:(1)With lateral thrust,there was no significant change in the C7T1-T7T8 intervertebral disc.The concave and convex stress of T7T8-L4L5 segment decreased first and then increased with the increase of lateral thrust force.The correction effect of lateral thrust on the segment near T8T9 was obvious and weakened with the extension of the segment to the cephalic and caudal ends.At 120 N of lateral thrust,the thoracic Cobb angle changed from 53.2° to 32.5° and the lumbar Cobb angle changed from 50.2° to 43.9°.(2)With the vertical distraction,the thoracic intervertebral disc stresses first decreased and then increased,and all the lumbar disc stresses decreased.The C7 displacement was the most obvious,and the correction effect gradually diminished with the segment extended to the caudal end.At a vertical distraction force of 120 N,the thoracic Cobb angle changed from 53.2° to 39.4° and the lumbar Cobb angle changed from 50.2° to 47.6°.(3)It is concluded that both orthopedic modalities provide improvement in the degree of scoliosis,with the thoracic correction being greater than the lumbar correction.Also,the asymmetric stress distribution on the concave and convex sides is improved,which contributes to normal bone growth.A vertical distraction approach is appropriate for larger Cobb angles,and a lateral thrust approach is appropriate for smaller Cobb angles.The results of this study help to understand the mechanism of spinal orthosis and provide a theoretical basis for the choice of orthopedic approach.

OBJECTIVE: To evaluate the efficacy and safety of Shexiang Tongxin Dropping Pill (STDP) in treating stable angina patients with phlegm-heat and blood-stasis syndrome by exercise duration and metabolic equivalents. METHODS: This multicenter, randomized, double-blind, placebo-controlled clinical trial enrolled stable angina patients with phlegm-heat and blood-stasis syndrome from 22 hospitals. They were randomized 1:1 to STDP (35 mg/pill, 6 pills per day) or placebo for 56 days. The primary outcome was the exercise duration and metabolic equivalents (METs) assessed by the standard Bruce exercise treadmill test after 56 days of treatment. The secondary outcomes included the total angina symptom score, Chinese medicine (CM) symptom scores, Seattle Angina Questionnaire (SAQ) scores, changes in ST-T on electrocardiogram and adverse events (AEs). RESULTS: This trial enrolled 309 patients, including 155 and 154 in the STDP and placebo groups, respectively. STDP significantly prolonged exercise duration with an increase of 51.0 s, compared to a decrease of 12.0 s with placebo (change rate: -11.1% vs. 3.2%, P<0.01). The increase in METs was significantly greater in the STDP group than in the placebo group (change: -0.4 vs. 0.0, change rate: -5.0% vs. 0.0%, P<0.01). The improvement of total angina symptom scores (25.0% vs. 0.0%), CM symptom scores (38.7% vs. 11.8%), reduction of nitroglycerin consumption (100.0% vs. 11.3%), and all domains of SAQ, were significantly greater with STDP than placebo (all P<0.01). The changes in Q-T intervals at 28 and 56 days from baseline were similar between the two groups (both P>0.05). Twenty-five participants (16.3%) with STDP and 16 (10.5%) with placebo experienced AEs (P=0.131), with no serious AEs observed. CONCLUSION STDP could improve exercise tolerance in patients with stable angina and phlegm-heat and blood stasis syndrome, with a favorable safety profile. (Registration No. ChiCTR-IPR-15006020).
Humans ; Double-Blind Method ; Drugs, Chinese Herbal/adverse effects* ; Male ; Female ; Middle Aged ; Angina, Stable/physiopathology* ; Aged ; Syndrome ; Treatment Outcome ; Placebos ; Tablets

OBJECTIVES: Recent evidence suggests that the gut may be a primary site of metformin action. However, studies on the effects of metformin on gut microbiota remain limited, and its impact on gut microbial metabolites such as short-/medium-chain fatty acids is unclear. This study aims to investigate the effects of metformin on gut microbiota, short-/medium-chain fatty acids, and associated metabolic benefits in high-fat diet rats. METHODS: Twenty-four Sprague-Dawley rats were randomly divided into 3 groups: 1) Normal diet group (ND group), fed standard chow; 2) high-fat diet group (HFD group), fed a high-fat diet; 3) high-fat diet + metformin treatment group (HFD+Met group), fed a high-fat diet for 8 weeks, followed by daily intragastric administration of metformin solution (150 mg/kg body weight) starting in week 9. At the end of the experiment, all rats were sacrificed, and serum, liver, and colonic contents were collected for assessment of glucose and lipid metabolism, liver pathology, gut microbiota composition, and the concentrations of short-/medium-chain fatty acids. RESULTS: Metformin significantly improved HFD-induced glucose and lipid metabolic disorders and liver injury. Compared with the HFD group, the HFD+Met group showed reduced abundance of Blautia, Romboutsia, Bilophila, and Bacteroides, while Lactobacillus abundance significantly increased (all P<0.05). Colonic contents of butyric acid, 2-methyl butyric acid, valeric acid, octanoic acid, and lauric acid were significantly elevated (all P<0.05), whereas acetic acid, isoheptanoic acid, and nonanoic acid levels were significantly decreased (all P<0.05). Spearman correlation analysis revealed that Lactobacillus abundance was negatively correlated with body weight gain and insulin resistance, while butyrate and valerate levels were negatively correlated with insulin resistance and liver injury (all P<0.05). CONCLUSIONS Metformin significantly increases the abundance of beneficial bacteria such as Lactobacillus and promotes the production of short-/medium-chain fatty acids including butyric, valeric, and lauric acid in the colonic contents of HFD rats, suggesting that metformin may regulate host metabolism through modulation of the gut microbiota.
Animals ; Metformin/pharmacology* ; Rats, Sprague-Dawley ; Diet, High-Fat/adverse effects* ; Rats ; Gastrointestinal Microbiome/drug effects* ; Male ; Fatty Acids, Volatile/metabolism* ; Fatty Acids/metabolism*

OBJECTIVE: To explore the relationship between serum chloride levels and prognosis in patients with hepatic coma in the intensive care unit (ICU). METHODS: We analyzed 545 patients with hepatic coma in the ICU from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Associations between serum chloride levels and 28-day and 1-year mortality rates were assessed using restricted cubic splines (RCSs), Kaplan-Meier (KM) curves, and Cox regression. Subgroup analyses, external validation, and mechanistic studies were also performed. RESULTS: A total of 545 patients were included in the study. RCS analysis revealed a U-shaped association between serum chloride levels and mortality in patients with hepatic coma. The KM curves indicated lower survival rates among patients with low chloride levels (< 103 mmol/L). Low chloride levels were independently linked to increased 28-day and 1-year all-cause mortality rates. In the multivariate models, the hazard ratio ( HR) for 28-day mortality in the low-chloride group was 1.424 (95% confidence interval [ CI]: 1.041-1.949), while the adjusted hazard ratio for 1-year mortality was 1.313 (95% CI: 1.026-1.679). Subgroup analyses and external validation supported these findings. Cytological experiments suggested that low chloride levels may activate the phosphorylation of the NF-κB signaling pathway, promote the expression of pro-inflammatory cytokines, and reduce neuronal cell viability. CONCLUSION Low serum chloride levels are independently associated with increased mortality in patients with hepatic coma.
Humans ; Male ; Female ; Middle Aged ; Intensive Care Units ; Prognosis ; Chlorides/blood* ; Aged ; Coma/blood* ; Adult