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 observe the expression and localization of group Ⅰ metabotropic glutamate receptors (mGluR1/ 5) in rat superior cervical ganglion (SCG) and the effect of chronic intermittent hypoxia (CIH) on mGluR1/ 5 protein level. Methods Twelve male SD rats were randomly divided into control group(Ctrl)and CIH group(CIH), 6 rats in each group. After 6 weeks of modeling, the effect of CIH on mGluR1/ 5 protein level was detected by Western blotting, the expression and distribution of mGluR1/ 5 in SCG were detected by immunohistochemistry and double-immunofluorescent staining. Results mGluR1/ 5 was expressed in rat SCG. mGluR1 was distributed in neurons and small intensely fluorescent (SIF) cells, but not in satellite glial cells (SGCs), nerve fibers and blood vessels, whereas mGluR5 was mainly distributed in nerve fibers and a little in neurons, but not in SGCs, SIF cells and blood vessels. CIH increased the protein levels of mGluR1/ 5 (P<0. 01) in rat SCG. Conclusion Both mGluR1 and mGluR5 are expressed in the rat SCG, but their distribution are different, and the increased protein levels of both may be involved in CIH-induced hypertension.

A new Schiff base modified MCM-41 molecular sieve(N-MCM-41)was synthesized via post-grafting method with 2-pyridine formaldehyde for efficient removal of lead ions(Pb2+)from aqueous solution.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Fourier transform-infrared(FT-IR)spectroscopy,thermogravimetric analysis(TGA),and X-ray photoelectron spectroscopy(XPS)were employed to characterize the structure,morphology,surface functional groups and chemical states of N-MCM-41.Moreover,the adsorption behavior of Pb2+by N-MCM-41 was systematically studied.Batch adsorption studies revealed that N-MCM-41 showed the maximal adsorption capacity of 101.3 mg/g at 45℃and pH=5.5 under the initial Pb2+ concentration of 80 mg/L after 180 min adsorption.The adsorption process conformed to the Langmuir isotherm model and the pseudo-second-order kinetics model.The adsorption of Pb2+by N-MCM-41 was a spontaneous and endothermic process.Adsorption mechanism analyses suggested that functional groups on N-MCM-41 had strong coordination ability with Pb2+to improve the adsorption capacity.The synthesized N-MCM-41 adsorbent exhibited excellent reusability in five regeneration cycles.Overall,this study showed that the N-MCM-41 had good application prospect to remove Pb2+ from aqueous solution.

Objective To observe the regulatory mechanism of drug-containing serum of Jinghou Zengzhi Prescription based on qi and blood replenishing method on the expression of growth and differentiation factor 9(GDF9)and apoptosis of ovarian granulosa cells in rats with controlled ovarian hyperstimulation(COH).Methods Serum of COH rats(blank serum)and serum of COH rats gavaged by the Jinghou Zengzhi Prescription were prepared.A COH rat model was established and ovarian granulosa cells were collected.The experiment was divided into 5 groups:blank serum group,drug-containing serum group,drug-containing serum+SB203580[p38 mitogen-activated protein kinase(p38MAPK)inhibitor]group,drug-containing serum + PDTC[nuclear transcription factor κB(NF-κB)inhibitor]group,drug-containing serum + SB203580 + PDTC group.The mRNA expression levels of p38MAPK,casein kinase 2(CK2),nuclear transcription factor κB inhibitor α(IκBα),NF-κB and GDF9 were detected by real-time quantitative polymerase chain reaction(qRT-PCR),and GDF9 protein expression level was detected by Western Blot,and ovarian granulosa cell apoptosis was detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL).Results The drug-containing serum of Jinghou Zengzhi Prescription decreased the mRNA expressions of p38MAPK and NF-κB,elevated the mRNA expressions of CK2 and IκBα,increased the mRNA and protein expression levels of GDF9,and decreased the apoptosis rate of ovarian granulosa cells in COH rats.The addition of p38MAPK inhibitor SB203580 alone and the addition of NF-κB inhibitor PDTC alone both promoted the mRNA and protein expressions of GDF9 and reduced the apoptosis rate of granulosa cells.Conclusion The drug-containing serum of Jinghou Zengzhi Prescription based on qi and blood replenishing method can promote the expression of GDF9 and inhibit the apoptosis of ovarian granulosa cells in rats with COH,and its mechanism may be related to the regulation of the expression of genes of the dual signaling pathways of p38MAPK and NF-κB.

AIM To explore the effects of Buyang Huanwu Decoction on mitochondrial oxidative damage and PKCε-Nampt pathway in rats following cerebral ischemia reperfusion(I/R).METHODS The rats were randomly divided into the sham operation group,the model group,Buyang Huanwu Decoction group(14.3 g/kg)and edaravone group(3 mg/kg).Except those of the sham operation group,SD rats of other groups were induced into models of brain I/R injury by MCAO method,followed by corresponding drug administration 24 hours after operation.After 7 days of administration,the rats had their neurological deficit evaluated by neurological function scoring;thier expression of neuron marker MAP-2 detected by immunofluorescence staining;their neuron damage observed and the oxidative damage evaluated through assessment of their ROS levels and MDA and SOD activities;their changes of mitochondrial membrane potential detected by fluorescent probe JC-1;their ratio of NAD+/NADH detected using modified enzyme circulation method;their expressions of PKCε,p-PKCε and Nampt proteins detected with Western blot;and their positive expressions of p-PKCε and Nampt proteins detected with immunohistochemistry method.RESULTS Compared with the model group,Buyang Huanwu Decoction group shared decreased cerebral infarction volume and neurological function score(P<0.05);increased cerebral fluorescence intensity of MAP-2(P<0.05);reduced neuronal damage,decreased cerebral levels of ROS and MDA(P<0.05);increased SOD activity,mitochondrial membrane potential and NAD+/NADH ratio(P<0.05);and increased protein expressions of p-PKCε and Nampt(P<0.05).CONCLUSION Buyang Huanwu Decoction can improve mitochondrial function and reduce brain I/R injury in rats by activating their PKCε-Nampt signaling pathway.

ObjectiveThe detection of RNA single nucleotide polymorphism (SNP) is of great importance due to their association with protein expression related to various diseases and drug responses. At present, splintR ligase-assisted methods are important approaches for RNA direct detection, but its specificity will be limited when the fidelity of ligases is not ideal. The aim of this study was to create a method to improve the specificity of splintR ligase for RNA detection. MethodsIn this study, a dual-competitive-padlock-probe (DCPLP) assay without the need for additional enzymes or reactions is proposed to improve specificity of splintR ligase ligation. To verify the method, we employed dual competitive padlock probe-mediated rolling circle amplification (DCPLP-RCA) to genotype the CYP2C9 gene. ResultsThe specificity was well improved through the competition and strand displacement of dual padlock probe, with an 83.26% reduction in nonspecific signal. By detecting synthetic RNA samples, the method demonstrated a dynamic detection range of 10 pmol/L-1 nmol/L. Furthermore, clinical samples were applied to the method to evaluate its performance, and the genotyping results were consistent with those obtained using the qPCR method. ConclusionThis study has successfully established a highly specific direct RNA SNP detection method, and provided a novel avenue for accurate identification of various types of RNAs.

To explore the absorption mechanism of APS-Ⅱ in vivo by establishing M cell model. First, Astragalus polysaccharides (APS) was divided into two different molecular weight polysaccharides APS-I ( > 2 000 kDa) and APS-II (10 kDa) by ultrafiltration, and APS-II (10 kDa) was prepared and fluorescently labeled. Meanwhile, M cell model was constructed by Caco-2 cells and Raji cells. The M cell model was treated with transport inhibitors to explore the transport of APS-Ⅱ on M cells. The results show that FITC has been successfully labeled to the end of APS-Ⅱ, and the M cell model was successfully constructed, which found that APS-Ⅱ could be transported by M cells, and four transport inhibitors of 5-(N-ethyl-N-isopropyl) amiloride (EIPA), genistein, dynasore and nocodazole indicated that APS-II may enter cells through clathrin and caveolin-mediated endocytosis.

This paper applied gas chromatography-mass spectrometry (GC-MS), network pharmacology and nuclear magnetic resonance hydrogen spectroscopy (¹H NMR) metabolomics techniques to study the material basis and mechanism of action of Ning Shen Essential Oil in anti-insomnia. The main volatile components of Ning Shen Essential Oil were analyzed by gas chromatography-mass spectrometry (GC-MS), and the insomnia-related targets were predicted using the Traditional Chinese Medicine Systematic Pharmacology Database and Analytical Platform (TCMSP) and the databases of GeneCards, OMIM and Drugbank. The insomnia model of rats was replicated by intraperitoneal injection of 4-chloro-DL-phenylalanine (PCPA). Animal experiments were approved by the Animal Ethics Committee of Shandong University of Traditional Chinese Medicine (Ethics No.: SDUTCM20221025010). The modulating effect of Compound Ning Shen Essential Oil on anxiety behavior of rats was evaluated by behavioral related indexes. The serum levels of corticotropin-releasing hormone (CRH), adrenotropic corticotropic hormone (ACTH) and melatonin (MT) were measured by enzyme-linked immunoassay (ELISA). Rat serum and hippocampus were taken for nuclear magnetic resonance (¹H NMR) metabolomics to detect the changes of endogenous metabolites in rat serum hippocampus, to designate the differential metabolites and to construct metabolic pathways. The results showed that the exercise distance in the open field experiment and the number of times and time to enter the open arm in the elevated cross maze experiment of the rats in the model group were significantly reduced (P < 0.05, P < 0.01). The behavioral indexes of rats improved to different degrees after the administration of Ning Shen Essential Oil. The serum CRH and ACTH levels of rats in the model group increased significantly (P < 0.05, P < 0.01), and the MT level decreased significantly (P < 0.01); After the intervention, serum CRH and ACTH levels were reduced to different degrees, and MT levels could be regressed. ¹H NMR metabolomics screened 10 potential biomarkers related to insomnia, which involved in 6 potential metabolic pathways. A total of 35 components of Ning Shen Essential Oil were detected by GC-MS, the main component targets of Ning Shen Essential Oil and insomnia disease targets were intersected, a total of 172 intersecting genes were screened, and 26 core targets were identified. The study demonstrated that Ning Shen Essential Oil had protective effects against PCPA-induced insomnia in rats, which was probably correlated with regulation of the hypothalamic-pituitary-adrenal axis (HPA) related hormones and metabolism of amino acids, lipids and choline.

BACKGROUND: The effects of acupuncture have varied in different randomized controlled trials (RCTs), and there are many factors that influence treatment effect of acupuncture in different outcomes, with conflicting results. OBJECTIVE: To identify factors and their impact on the treatment effect of acupuncture in different outcomes. METHODS: Acupuncture RCTs were searched from 7 databases including Medline (PubMed), Embase, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, Wanfang Database, VIP Database, and China Biology Medicine disc between January 1st, 2015 and December 31st, 2019. Eligible studies must compare acupuncture to no acupuncture, sham acupuncture, or waiting lists, and report at least 1 patient-important outcome. A multi-level meta-regression was conducted using a 3-level robust mixed model and univariate analyses were performed for all independent variables, even those excluded from the multivariable model due to collinearities. We used thresholds of 0.2 and 0.4 for the difference of standardized mean differences (SMDs), categorising them as small (<0.2), moderate (0.2-0.4), or large (>0.4) effects. RESULTS: The pain construct analysis involved 211 effect estimates from 153 studies and 14 independent variables. High-frequency acupuncture treatment sessions produced larger effects compared to low-frequency sessions [large magnitude, the difference of adjusted SMDs 0.46, 95% confidence interval (CI) 0.07 to 0.84; P=0.02]. The non-pain symptoms construct analysis comprised 323 effect estimates from 231 studies and 15 independent variables. Penetrating acupuncture showed moderately larger effects when compared to non-penetrating acupuncture (0.30, 95% CI 0.06 to 0.53; P=0.01). The function construct analysis included 495 effect estimates from 274 studies and 14 independent variables. Penetrating acupuncture and the flexible acupuncture regimen showed moderately larger effects, compared to non-penetrating acupuncture and fixed regimen, respectively (0.40, 95% CI 0 to 0.80; P=0.05; 0.29, 95% CI 0.06 to 0.53; P=0.01). CONCLUSIONS High-frequency acupuncture sessions appear to be a more effective approach to managing painful symptoms. Penetrating acupuncture demonstrated greater effect in relieving non-painful symptoms. Both penetrating acupuncture type and flexible acupuncture regimen were linked to significant treatment effects in function outcomes. Future studies should consider the factors that are significantly associated with the effects of acupuncture in patient-important outcomes.
Humans ; Randomized Controlled Trials as Topic ; Acupuncture Therapy/methods* ; Pain ; Pain Management ; China

Objective To explore the cut-off value of three dimensional(3D)vena contracta area(VCA)in diagnosing severe tricuspid regrugitation(TR)under different etiologies and its accuracy and practicality in clinical application.Methods From Mar 2019 to May 2021,ninety-two patients with confirmed TR underwent two dimensional(2D)and 3D transthoracic echocardiography.The correlation and consistency between 3D VCA 3D calculated based on the proximal isokinetic surface area(PISA)effective regurgitant orifice area(EROA)was calculated.Comprehensive 2D multi-parameter method was used as a reference method to calculate the cut-off value of the diagnosis of severe TR.Results A total of 85 patients were ultimately included.3D VCA and 3D PISA EROA had similar and acceptable correlations in both primary TR and secondary TR(primary TR:r=0.831,P<0.01;secondary TR:r=0.806,P<0.01).Bland-Altman analysis showed that 3D VCA overestimated TR compared with 3D PISA EROA(62%overestimated in the total patient population,51%overestimated in primary TR,and 74%overestimated in secondary TR).In secondary TR,the cut-off value of 3D VCA for diagnosing severe TR was 0.45 cm2(sensitivity 89%,specificity 82%);combining clinical symptoms,positive 2D PISA EROA results and 3D VCA results for severe TR,the chi-square value was higher than those only included clinical symptoms or incorporated clinical symptoms and positive 2D PISA EROA results(42.168 vs.26.059 and 16.759,P<0.01).Conclusion 3D VCA would overestimate TR,and had high and incremental diagnostic value for evaluating severe TR in secondary TR.