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.

To explore the inhibitory effect of ginkgolide B (GB) on MH7A human fibroblast-like synoviocytes (FLS) and its potential mechanism. Firstly, 20 μg/L tumor necrosis factor-α (TNF-α) was pretreated with MH7A to establish a cell model of arthritis. After incubation of MH7A cells with various concentrations of GB, CCK-8 assay, Transwell assay, and flow cytometry (FCM) were separately used to detect cell viability, cell invasion, and cell apoptosis rate and cell cycle; Real-time quantitative PCR and Western blot assay were performed to detect the apoptosis- and cycle-related gene transcriptions and protein expressions, respectively. The results showed that compared with the control group, GB dose- and time-dependently suppressed cell viability to a greater extent; GB significantly reduced cell invasive ability and increased cell apoptosis rate and proportion of G0/G1 phase in MH7A cells, along with increased transcription levels of Bcl-2-associated X protein (Bax) and p21 mRNA and decreased transcription levels of Bcl-2, myeloid cell leukemia 1(Mcl-1), protein kinase B (PKB; AKT), IP3K, Cyclin D1 and cyclin-dependent kinase 4 (CDK4) mRNA; GB remarkably increased expression levels of Bax, p21, and cleaved-Caspase 3 protein and decreased expression levels of Bcl-2, Mcl-1, p-AKT, p-PI3K, Cyclin D1, and CDK4 protein, with decreased ratios of p-PI3K/PI3K, p-AKT/AKT, and Bcl-2/Bax. In conclusion, GB blocks the G1-to-S cell cycle transition, suppresses cell viability and cell invasion and induces cell apoptosis of MH7A human RA-FLS via suppressing the PI3K/AKT signaling pathway.

Aim To investigate the therapeutic effect of the MW-9 on ulcerative colitis(UC)and reveal the underlying mechanism, so as to provide a scientific guidance for the MW-9 treatment of UC. Methods The model of lipopolysaccharide(LPS)-stimulated RAW264.7 macrophage cells was established. The effect of MW-9 on RAW264.7 cells viability was detected by MTT assay. The levels of nitric oxide(NO)in RAW264.7 macrophages were measured by Griess assay. Cell supernatants and serum levels of inflammatory cytokines containing IL-6, TNF-α and IL-1β were determined by ELISA kits. Dextran sulfate sodium(DSS)-induced UC model in mice was established and body weight of mice in each group was measured. The histopathological damage degree of colonic tissue was assessed by HE staining. The protein expression of p-p38, p-ERK1/2 and p-JNK was detected by Western blot. Results MW-9 intervention significantly inhibited NO release in RAW264.7 macrophages with IC50 of 20.47 mg·L-1 and decreased the overproduction of inflammatory factors IL-6, IL-1β and TNF-α(P<0.05). MW-9 had no cytotoxicity at the concentrations below 6 mg·L-1. After MW-9 treatment, mouse body weight was gradually reduced, and the serum IL-6, IL-1β and TNF-α levels were significantly down-regulated. Compared with the model group, MW-9 significantly decreased the expression of p-p38 and p-ERK1/2 protein. Conclusions MW-9 has significant anti-inflammatory activities both in vitro and in vivo, and its underlying mechanism for the treatment of UC may be associated with the inhibition of MAPK signaling pathway.

Objective To establish a low density, high purity and high stability in vitro culture method of primary hippocampal neurons of fetal rats by co-culturing hippocampal and cortical cells, so as to obtain higher purity and better vitality of primary hippocampal neurons disease. Methods The fetal rat hippocampal tissue was isolated from 16-18 days pregnant SD rats, then cut and digested by 0.125% trypsin. The obtained cell suspension was filtered by 200 mesh cell sieve, and then the obtained cell suspensions were then inoculated into the inner layer and outer ring of the culture plate in a surrounding form. They were co-cultured in DMEM/F12 medium containing 10% horse serum. After 4-6 hours of cell adhesion, the culture medium was changed to maintenance medium (Neurobasal+2% B27+0.5 mmol/L glutamine). Then the cell viability was detected with CCK-8 kit and the purity of hippocampal neurons was detected by immunofluorescent staining. Results Hippocampal neurons grew well and formed crisscross neural networks after 5 days. And it could survive for 3 weeks. The purity of hippocampal neurons was up to 98%. Conclusion The method of co-culturing hippocampal and cortical cells can obtain high-purity, high activity, high survival rate, and high stability primary hippocampal neurons from fetal rats, which can provide certain experimental conditions for the study of hippocampal neuron related diseases in the nervous system and is worthy of promotion and application.

In the past few decades, microbubbles were widely used as ultrasound contrast agents in the field of tumor imaging. With the development of research, ultrasound targeted microbubble destruction technology combined with drug-loaded microbubbles can achieve precise drug release and play a therapeutic role. As a micron-scale carrier, microbubbles are difficult to penetrate the endothelial cell space of tumors, and nano-scale drug delivery system—nanobubbles came into being. The structure of the two is similar, but the difference in size highlights the unique advantages of nanobubbles in drug delivery. Based on the classification principle of shell materials, this review summarized micro/nanobubbles used for ultrasound diagnosis or treatment and discussed the possible development directions, providing references for the subsequent development.

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.

Alzheimer's disease(AD)is a multi-cause neurodegenerative disease characterized by memory impairment.There have been serious obstacles to the effective treatment of AD.Acupuncture,as a component of traditional Chinese medicine,plays an important role in the treatment of AD.Acupuncture has been shown to protect neurons from degeneration and promotes axonal regeneration in neurodegenerative diseases such as AD.According to existing studies,the mechanisms of acupuncture on AD include the following aspects:modulation of Aβ metabolism,tau phosphorylation,cholinergic neurotransmitters,neuroinflammation,synaptic and neuronal function,autophagy,brain glucose metabolism,intestinal flora,and inhibition of nerve cell apoptosis,which in turn improves cognition.

Objective To investigate the therapeutic effect of Huatan Jieyu Anshen Decoction(mainly with the actions of resolving phlegm,relieving depression and calming mind)combined with abdominal vibration tuina manipulations on chronic insomnia in the elderly.Methods Ninety-four cases of elderly patients with chronic insomnia of phlegm-heat harassing the interior type were randomly divided into the observation group and the control group,with 47 cases in each group.The control group was given Huatan Jieyu Anshen Decoction orally,while the observation group was given oral use of Huatan Jieyu Anshen Decoction combined with abdominal vibration tuina manipulations.The course of treatment for the two groups lasted for 4 weeks.Before and after the treatment,the two groups were observed in the changes of traditional Chinese medicine(TCM)syndrome scores,Pittsburgh Sleep Quality Index(PSQI)score,Athens Insomnia Scale(AIS)score,Fatigue Scale-14(FS-14)score,World Health Organization Quality-of-Life Brief Scale(WHOQOL-BREF)score,and the serum levels of melatonin(MT),dopamine(DA),and cortisol(CORT).After treatment,the clinical efficacy of the two groups was evaluated.Results(1)After 4 weeks of treatment,the total effective rate of the observation group was 97.88%(46/47),while that of the control group was 87.23%(41/47),and the intergroup comparison(tested by chi-square test)showed that the therapeutic efficacy of the observation group was superior to that of the control group(P＜0.01).(2)After treatment,the scores of primary and secondary TCM symptoms in the two groups were significantly decreased compared with those before treatment(P＜0.05),and the decrease of the scores of primary and secondary TCM symptoms in the observation group was significantly superior to that in the control group(P＜0.01).(3)After treatment,the PSQI scores,AIS scores,and FS-14 scores in the two groups were significantly decreased compared with those before treatment(P＜0.05),and the WHOQOL-BREF scores were significantly increased compared with those before treatment(P＜0.05).The decrease of the PSQI scores,AIS scores and FS-14 scores as well as the increase of the WHOQOL-BREF scores in the observation group was significantly superior to that in the control group(P＜0.01).(4)After treatment,the serum MT level of both groups was significantly higher than that before treatment(P＜0.05),and the serum DA and CORT levels were significantly lower than those before treatment(P＜0.05).The increase in serum MT level and the decrease in serum DA and CORT levels of the observation group were significantly superior to those of the control group(P＜0.01).Conclusion The combined therapy of Huatan Jieyu Anshen Decoction combined with vibration tuina manipulations can achieve satisfactory efficacy in the elderly patients with chronic insomnia of phlegm-heat harassing the interior syndrome.The therapy is effective on regulating the central nervous system of the patients,improving the quality of the sleep,and promoting the relief of fatigue and the enhancement of the quality of life,which has great significance to the enhancement of the overall therapeutic efficacy of insomnia.

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 distribution of abnormal karyotypes and their associations with clinical manifestations of the infertile patients in southern Sichuan Province.Methods A total of 4 157 infertile patients who attended the Reproductive Medicine Center of our hospital from July 2018 to June 2021 were included.The chromosome karyotype in peripheral blood was detected by G-banding,and their semen analysis results,uterine development and other clinical data were collected.Results Among the 4 157 patients,chromosomal polymorphisms were found in 239 cases(5.75％),and abnormal karyotypes wee found 137 cases(3.30％).The abnormal karyotypes included 57 cases(41.61％)of sex chromosome aneuploidy,6 cases(4.38％)of Robertsonian transloca-tions,32 cases(23.36％)of balanced translocations,21 cases(15.33％)of chromosomal inversions,9 cases(6.57％)of mosai-cism,8 cases(5.84％)of marker chromosomes,3 cases(2.19％)of sex reversal and 1 case(0.73％)of sex chromosome deletion.In male patients with abnormal karyotypes,91.58％showed abnormal semen parameters,while in those with polymorphic karyotypes,55％had abnormal semen parameters.The patients with Turner syndrome had significantly smaller uterine dimensions(longitudinal,transverse,and anteroposterior)compared to the normal control group(P＜0.01).Conclusion Chromosomal abnormalities should be the important cause of infertility.Conducting karyotype analysis combining with clinical manifestations is crucial examination for the di-agnosis and reproductive guidance of infertile patients.