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 ; Vascular Stiffness ; Coal Mining ; Occupational Diseases/epidemiology* ; Risk Factors ; Coal ; Miners

Fluorescence anisotropy(FA)analysis has many advantages such as no requirement of separation,high throughput and real-time detection,and thus has been widely used in many fields,including biochemical analysis,food safety detection,environmental monitoring,etc.However,due to the small volume or mass of the target,its combination with the fluorescence probe cannot produce significant signal change.To solve this issue,researchers often use nanomaterials to enhance the mass or volume of fluorophore to improve the sensitivity.Nevertheless,this FA amplification strategy also has some disadvantages.Firstly,nanomaterials are easy to quench fluorescence.As a result,the FA value is easily influenced by light scattering,which reduces the detection accuracy.Secondly,fluorescent probes in most methods require complex modification steps.Therefore,it is necessary to develop new FA probes that do not require the amplification of volume and mass or modification.As a new kind of nanomaterials,luminescent metal-organic framework(MOF)has a large volume(or mass)and strong fluorescence emission.It does not require additional signal amplification materials.As a consequence,it can be used as a potential FA probe.This study successfully synthesized a lanthanide metal organic framework(Ce-TCPP MOF)using cerium ion(Ce3+)as the central ion and 5,10,15,20-tetra(4-carboxylphenyl)porphyrin(H2TCPP)as the ligand through microwave assisted method,and used it as a novel unmodified FA probe to detect phosphate ions(Pi).In the absence of Pi,Ce-TCPP MOF had a significant FA value(r).After addition of Pi,Pi reacted with Ce3+in MOF and destroyed the structure of MOF into the small pieces,resulting in a decrease in r.The experimental results indicated that with the increase of Pi concentration,the change of the r of Ce-TCPP MOF(Δr)gradually increased.The Δr and Pi concentration showed a good linear relationship within the range of 0.5-3.5 μmol/L(0.016-0.108 mg/L).The limit of detection(LOD,3σ/k)was 0.41 μmol/L.The concentration of Pi in the Jialing River water detected by this method was about 0.078 mg/L,and the Pi value detected by ammonium molybdate spectrophotometry was about 0.080 mg/L.The two detection results were consistent with each other,and the detection results also meet the ClassⅡwater quality standard,proving that this method could be used for the detection of Pi in complex water bodies.

Immunoassays are widely used in medicine, food, environment and other fields due to having the advantages of simpleness, rapidness and accuracy. Combining immunoassays with nanomaterials can improve the performance of immunoassays. Compared with traditional nanomaterials, upconversion nanoparticles (UCNPs) have excellent optical properties such as good photostability, long luminescence lifetime and narrow and tunable emission bands, which can significantly reduce background noise and improve analytical sensitivity when combined with immunoassay. This paper briefly introduces the luminescence mechanism of UCNPs, summarizes the synthesis and surface modification methods of UCNPs. And then 5 UCNPs-based immunoassay techniques, namely, fluorescence resonance energy transfer, inner filter effect, magnetic separation technique, upconversion-linked immunosorbent assay and upconversion immunochromatography, are discussed in detail. These sensing protocols of UCNPs-based immunoassays have been successfully utilized to detect various targets, including small molecules, macromolecules, and pathogens, all of which closely related to food safety, human health, and environmental pollution. Finally, the challenges and prospects of this technique are summarized and prospected. Although the UCNPs immunoassays based on antibodies and antigens have made great progress, most of the research is still in the stage of laboratory, and there is a long way to go to realize its social applications. There is a series of challenges need to be overcome. (1) Designing excellent water soluble and dispersive upconversion nanomaterials is needed. Hydrophilic ligands are bound to smaller upconversion nanoparticles and removing hydrophobic surface ligands are the most widely used methods to improve solubility and dispersity. (2) Multi-detection technology platforms and multi-mode simultaneous detection platforms have great potential, which will improve the efficiency of point of care detection. (3) The researchers also need to focus on some important problems. For examples, the upconversion luminescence efficiency of UCNPs is difficult to maintain, the synthesis method is complex, and the surface modification degree and functionalization are difficult to control.

Objective To explore the prognostic value of long non-coding RNAs(lncRNAs)as novel biomarkers for stomach adenocarcinoma(STAD).Methods RNA-seq transcriptome data and clinical details for STAD were downloaded from the The Cancer Genome Atlas(TCGA)database.Differentially expressed lncRNAs were identified by bioinformatics analysis.Survival analysis,independent prognostic analysis and receiver operating characteristic(ROC)curve were used to identify lncRNAs with independent prognostic value.Then,Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)were used to evaluate the biological profiles of the co-expressed genes.Finally,oncoPredict R package was used to predict the drug sensitivity.Results A total of 1 583 differentially expressed lncRNAs were identified from STAD tumor tissues.A lncRNAs AP000695.1 with survival and independent prognostic value was screened.The area under 5-year survival ROCs was 0.836.AP000695.1 was co-expressed with 16 genes involved in tumor cell invasion,metastasis and diffusion.Finally,anti-tumor drug sensitivity prediction revealed that patients in the low expression group were more sensitive to anti-tumor drugs.Conclusion This study discovered a risk factor lncRNAs AP000695.1 with independent prognostic value,may provide insight for individualized antitumor therapy and prognosis prediction for STAD patients.

Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible relationships with VA,VD,and other factors in postpartum women. Methods A total of 1,311 mothers(896 lactating and 415 non-lactating)from Hebei,Zhejiang,and Guangxi provinces were included in this study.The urinary iodine concentration(UIC),TSH,VA,and VD were measured. Results The median UIC of total and lactating participants were 142.00 μg/L and 139.95 μg/L,respectively.The median TSH,VA,and VD levels in all the participants were 1.89 mIU/L,0.44 μg/mL,and 24.04 ng/mL,respectively.No differences in the UIC were found between lactating and non-lactating mothers.UIC and TSH levels were significantly different among the three provinces.The rural UIC was higher than the urban UIC.Obese mothers had a higher UIC and a higher prevalence of excessive TSH.Higher UICs and TSHs levels were observed in both the VD deficiency and insufficiency groups than in the VD-sufficient group.After adjustment,no linear correlation was observed between UIC and VA/VD.No interaction was found between vitamins A/D and UIC on TSH levels. Conclusion The mothers in the present study had no iodine deficiency.Region,area type,BMI,and VD may be related to the iodine status or TSH levels.

Objective The purpose of this study was to investigate the bacterial communities of biting midges and ticks collected from three sites in the Poyang Lake area,namely,Qunlu Practice Base,Peach Blossom Garden,and Huangtong Animal Husbandry,and whether vectors carry any bacterial pathogens that may cause diseases to humans,to provide scientific basis for prospective pathogen discovery and disease prevention and control. Methods Using a metataxonomics approach in concert with full-length 16S rRNA gene sequencing and operational phylogenetic unit(OPU)analysis,we characterized the species-level microbial community structure of two important vector species,biting midges and ticks,including 33 arthropod samples comprising 3,885 individuals,collected around Poyang Lake. Results A total of 662 OPUs were classified in biting midges,including 195 known species and 373 potentially new species,and 618 OPUs were classified in ticks,including 217 known species and 326 potentially new species.Surprisingly,OPUs with potentially pathogenicity were detected in both arthropod vectors,with 66 known species of biting midges reported to carry potential pathogens,including Asaia lannensis and Rickettsia bellii,compared to 50 in ticks,such as Acinetobacter lwoffii and Staphylococcus sciuri.We found that Proteobacteria was the most dominant group in both midges and ticks.Furthermore,the outcomes demonstrated that the microbiota of midges and ticks tend to be governed by a few highly abundant bacteria.Pantoea sp7 was predominant in biting midges,while Coxiella sp1 was enriched in ticks.Meanwhile,Coxiella spp.,which may be essential for the survival of Haemaphysalis longicornis Neumann,were detected in all tick samples.The identification of dominant species and pathogens of biting midges and ticks in this study serves to broaden our knowledge associated to microbes of arthropod vectors. Conclusion Biting midges and ticks carry large numbers of known and potentially novel bacteria,and carry a wide range of potentially pathogenic bacteria,which may pose a risk of infection to humans and animals.The microbial communities of midges and ticks tend to be dominated by a few highly abundant bacteria.

Objective To investigate the expression of Midkine(MDK)in cholangiocarcinoma(CCA)and its value in predicting the prognosis of CCA,as well as the potential mechanism of the effect of MDK on the progression of CCA.Methods The data of CCA samples were obtained from TCGA database to analyze the difference in the expression of MDK between cancer tissue and paracancerous tissue and its association with clinical features,and the data collected from GEO database and 11 CCA patients who underwent surgical resection in The Fifth Medical Center of Chinese PLA General Hospital from June 2018 to September 2021 were used for validation.STRING and Cytoscape were used to construct a protein-protein interaction network,and gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were used to investigate the biological functions and tumor-related pathways involving MDK-related genes.In addition,TIMER and TISIDB databases were used to analyze the correlation between MDK expression and immune cell infiltration in CCA tissue.The independent-samples t test or the Mann-Whitney U test was used for comparison of continuous data between two groups,and the Fisher's exact test was used for comparison of categorical data between two groups.The Kaplan-Meier method was used to plot survival curves,and the Log-rank test was used for comparison between groups.The Spearman correlation analysis was used to investigate the correlation between two variables.Results The expression level of MDK in cancer tissue and paracancerous tissue of CCA patients was compared based on TCGA database,and the results of the non-paired and paired analyses showed that the expression level of MDK in CCA tumor tissue was significantly higher than that in paracancerous tissue(P<0.001).Transcriptome sequencing was performed for the tumor tissue and its corresponding paracancerous tissue from 11 CCA patients,and the results showed that the expression level of MDK in CCA tumor tissue was significantly higher than that in corresponding paracancerous tissue(P<0.01).High expression of MDK was associated with lymph node metastasis(P=0.045)and vascular invasion(P=0.044).Survival analysis showed that compared with the CCA patients with low MDK expression,the CCA patients with high MDK expression had significantly shorter overall survival time(χ2=5.30,P=0.028)and disease-specific survival time(χ2=6.25,P=0.019).The GO and KEGG enrichment analyses showed that the 30 MDK-related genes were closely associated with ubiquitin-mediated proteolysis and affected the prognosis of CCA patients.The TIMER analysis showed that the expression level of MDK was positively correlated with the infiltration of B cells(r=0.356,P=0.035 6)and dendritic cells(r=0.409,P=0.014 7)in tumor microenvironment of CCA;the TISIDB analysis showed that the expression level of MDK was positively correlated with CXCL16(r=0.465,P=0.004 67)and was negatively correlated with CXCL12(r=-0.389,P=0.019 7)and CXCR5(r=-0.393,P=0.018 5),and it was also negatively correlated with the immune checkpoint regulators VTCN1(r=-0.393,P=0.018 3),LTA(r=-0.380,P=0.022 7),and PVR(r=-0.350,P=0.037 3).Conclusion High expression of MDK is associated with poor prognosis in CCA patients,and MDK has the potential of being used as a molecular marker for predicting the prognosis of CCA.MDK may promote the development and progression of CCA by regulating ubiquitin-mediated proteolysis and the infiltration of B cells and dendritic cells.

Objective To investigate the reliability and validity of the assessment tools of Brief ICF Core Sets for Arthroplasty of Knee Osteoarthritis in Perioperative Period(ICSAKOPP). Methods From May,2022 to April,2023,320 patients undergoing knee arthroplasty were selected in Peking University Third Hospital,China-Japan Friendship Hospital,Peking University First Hospital and Chinese PLA General Hospital.Trained assessors used Brief ICSAKOPP to evaluate all enrolled patients before arthroplasty,three days(±one day)after arthroplasty,three weeks(±one week)after arthroplasty,and three months(±one month)after ar-throplasty.Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC)scores were recorded at the same time.Five professionals were asked to score all the items of Brief ICSAKOPP,and the content validity index(CVI)was caculated. Results A total of 64 cases were dropped down.CVI of all the items of the Brief ICSAKOPP were above 0.8,with a av-erage CVI of the scale of 0.938.The Cronbach's α coefficient of the Brief ICSAKOPP was 0.813.There was a moderate correlation(r=0.681,P<0.001)between the overall Brief ICSAKOPP and WOMAC scores,as well as body functional dimension score(r=0.668,P<0.001)and activities and participation dimension score(r=0.657,P<0.001). Conclusion Brief ICSAKOPP is good in content validity,internal consistency reliability and criterion validity.

The incidence of intrahepatic cholangiocarcinoma (ICC) continues to rise, and there are no effective drugs to treat it. The immune microenvironment plays an important role in the development of ICC and is currently a research hotspot. Icaritin (ICA) is an innovative traditional Chinese medicine for the treatment of advanced hepatocellular carcinoma. It is considered to have potential immunoregulatory and anti-tumor effects, which is potentially consistent with the understanding of "Fuzheng" in the treatment of tumor in traditional Chinese medicine. However, whether ICA can be used to treat ICC has not been reported. Therefore, in this study, sgp19/kRas, an in situ ICC mouse model with intact immune system, was selected to evaluate the efficacy of ICA in the treatment of ICC in vivo for the first time, and the effects of ICA on the tumor immune microenvironment of ICC mice were analyzed by flow cytometry. This experiment was approved by the Experimental Animal Ethics Committee of Capital Medical University (approval number: AEEI-2023-138). In this study, sgp19/kRas ICC mouse model was treated with oral gavage of 100 mg·kg^-1 ICA. We found that ICA significantly inhibited tumor growth and tumor cell proliferation in the sgp19/kRas ICC mouse model after 3 weeks of treatment. Flow cytometry analysis indicated that ICA treatment markedly reduced the proportion of M2 macrophages and increased the number of CD3⁺CD4⁺ T cells. In vitro experiments demonstrated that ICA promoted macrophage polarization towards the M1 phenotype while inhibiting polarization towards the M2 phenotype. Furthermore, transcriptomic analysis suggested that ICA enhanced Toll-like receptor 9 (TLR9) expression, influencing macrophage nitric oxide metabolism synthesis pathways and receptor-related activities, thereby regulating macrophage polarization. In summary, this study demonstrates that ICA treatment significantly delays tumor progression in sgp19/kRas ICC mouse models. Mechanistically, ICA may achieve its anti-ICC effects by upregulating TLR9 receptor expression levels, promoting macrophage polarization towards the M1 phenotype, and altering the tumor immune microenvironment.