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.

ObjectiveTo investigate how Xiaoyao Shukun decoction （XYSKD） regulates the formation and release of neutrophil extracellular traps （NETs） via the phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt）/mammalian target of rapamycin （mTOR） signaling pathway， thereby reducing inflammation， inhibiting the excessive proliferation of fibroblasts in pelvic adhesion tissue， decreasing adhesion and fibrosis， and repairing the tissue damage in sequelae of pelvic inflammatory disease （SPID）. MethodsA total of 84 Wistar rats were randomly allocated into seven groups： blank， model， XYSKD （8 mg·kg^-1）， mTOR agonist （10 mg·kg^-1）， mTOR agonist + XYSKD （10 mg·kg^-1+8 mg·kg^-1）， mTOR inhibitor （2 mg·kg^-1）， and mTOR inhibitor + XYSKD （2 mg·kg^-1+8 mg·kg^-1）. The rat model of SPID was constructed by starvation， fatigue， and ascending Escherichia coli infection. After 14 days of drug intervention， the ultrastructure of fibroblasts in the pelvic adhesion tissue was observed by transmission electron microscopy. The general morphology of the uterus， fallopian tube， and ovary was observed by laparotomy. The levels of interleukin-1β （IL-1β）， interleukin-17 （IL-17）， and tumor necrosis factor-α （TNF-α） in the peritoneal flushing fluid were determined by enzyme-linked immunosorbent assay （ELISA）. The expression of myeloperoxidase （MPO） and citrullinated histone 3 （H3） in the fallopian tube was detected by immunofluorescence. Western blot and Real-time quantitative polymerase chain reaction （Real-time PCR） were employed to determine the relative protein and mRNA levels， respectively， of neutrophil elastase （NE）， intercellular adhesion molecule-1 （CD54）， α-smooth muscle actin （α-SMA）， H3， PI3K， and Akt. ResultsCompared with the blank group， the model group presented a large number of collagen fibers in bundles， numerous cytoplasmic folds of fibroblasts， reduced or absent mitochondrial cristae， and disordered and expanded endoplasmic reticulum. By laparotomy， extensive pelvic congestion， connective tissue hyperplasia， thickening and hardening of the tubal end near the uterus， and tubal and ovarian adhesion or cyst were observed in the model group. In addition， the model group showed raised levels of IL-1β， IL-17， and TNF-α in the peritoneal flushing fluid （P<0.01）， increased average fluorescence intensities of MPO and H3 （P<0.01）， and up-regulated protein and mRNA levels of NE， H3， CD54， PI3K， and Akt （P<0.01）. Compared with the model group， the mTOR agonist group showed increased fibroblasts and cytoplasmic folds， absence of mitochondrial cristae， endoplasmic reticulum dilation， and evident collagen fiber hyperplasia. Pelvic adhesions were observed to cause aggravated damage to the uterine， fallopian tube， and ovarian tissues. The levels of IL-1β， IL-17， and TNF-α in the peritoneal lavage fluid elevated （P<0.01） and the average fluorescence intensities of MPO and H3 enhanced （P<0.01） in the mTOR agonist group. In contrast， the XYSKD group and the mTOR inhibitor group showcased decreased fibroblasts and collagen fibers， alleviated mitochondrial crista loss and endoplasmic reticulum dilation， improved morphology and appearance of the uterine， fallopian tube， and ovarian tissues， lowered levels of IL-1β， IL-17， and TNF-α in the peritoneal lavage fluid （P<0.01）， decreased average fluorescence intensities of MPO and H3 （P<0.01）， and down-regulated protein and mRNA levels of NE， H3， CD54， PI3K， and Akt （P<0.05）. Compared with the mTOR agonist group， the mTOR agonist + XYSKD group showed alleviated pathological changes in the pelvic tissue， declined levels of IL-1β， IL-17， and TNF-α （P<0.01）， decreased average fluorescence intensities of MPO and H3 （P<0.01）， and down-regulated protein levels of NE， H3， CD54， α-SMA， p-PI3K/PI3K， and p-Akt/Akt （P<0.01） and mRNA levels of NE， H3， CD54， α-SMA， PI3K， and Akt （P<0.01）. Compared with the mTOR inhibitor group， the mTOR inhibitor + XYSKD group demonstrated reduced pathological severity of the pelvic tissue， reduced levels of IL-1β， IL-17， and TNF-α （P<0.01）， decreased average fluorescence intensities of MPO and H3 （P<0.01）， and down-regulated protein and mRNA levels of NE and CD54 （P<0.05）. ConclusionXYSKD can inhibit the excessive formation and release of NETs via PI3K/Akt/mTOR to ameliorate the inflammatory environment and reduce fibrosis and adhesion of the pelvic tissue， thereby playing a role in the treatment of SPID. It may exert the effects by lowering the levels of IL-1β， IL-17， and TNF-α and down-regulating the expression of NE， H3， CD54， α-SMA， PI3K， and Akt in the pelvic adhesion tissue.

ObjectiveTo investigate the infection characteristics of respiratory syncytial virus (RSV) in children with acute respiratory tract infection (ARI) in Pudong New Area, Shanghai, from 2013 to 2023, so as to provide an evidence for the prevention and control of RSV in Shanghai. MethodsChildren who sought medical care at sentinel healthcare facilities in Pudong New Area, Shanghai, between January 2013 and December 2023 and met the case definition of ARI were included in the study. Nasopharyngeal swab samples were collected and tested for viral pathogens using real-time fluorescene PCR, and the clinical information of whom was collected simultaneously. ResultsA total of 4 980 children were included in the ARI surveillance, among whom 231 tested positive for RSV, with an overall detection rate of 4.64%. Of these, 106 cases were type A and 125 were type B. From 2013 to 2023, the detection rate of RSV in children showed an overall trend of initial increase followed by a decline, with higher detection rates in autumn and winter and lower rates in spring and summer. The RSV detection rate gradually decreased with age, with the highest rate observed in children <1 year old, accounting for 16.33% (80/490) of RSV-detection cases. Cough was the most common clinical symptom. Among the RSV-positive cases, 36 involved co-infection with another virus, 6 co-infected with three viruses, and 1 with mixed infection of four viruses. The most frequent co-infection was RSV and human coronavirus. ConclusionChildren under 1 year of age are more susceptible to RSV infection, with cough being the predominant symptom. RSV infection in Pudong New Area, Shanghai, mainly occurs in winter. Targeted prevention and control measures should be taken for children under 1 year old during the winter season to reduce the risk of both RSV infection and co-infection with human coronavirus and influenza virus.

Humans ; PPAR gamma/metabolism* ; Multiple Sclerosis ; Transcription Factors/metabolism* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha

Child ; Humans ; Mpox (monkeypox)/prevention & control* ; Disease Outbreaks

BACKGROUND:The risk factors for patellofemoral pain syndrome are still unclear and research on risk factors is gradually becoming a hot topic in order to improve the therapeutic outcome of this disease. OBJECTIVE:To investigate the relationship between lower limb alignment and patellofemoral pain syndrome in young male runners. METHODS:In the same running population,21 patients with bilateral knee pain,29 patients with single knee pain and 20 normal runners were collected from January 2021 to July 2022.Full-length X-ray examination of both lower limbs in standing position was performed in all subjects.The lateral distal femoral angle,medial tibial proximal angle,joint line congruence angle,hip-knee-ankle angle,and knee physical valgus angle were measured and statistically analyzed. RESULTS AND CONCLUSION:There was no significant difference in the parameters between the left and right knees in each group(P>0.05).Compared with the normal group,no significant changes in lateral distal femoral angle,medial tibial proximal angle,joint line congruence angle,and hip-knee-ankle angle were observed in the single knee pain group and double knee pain group,while the knee physical valgus angle was significantly increased in these two groups(P<0.05).To conclude,increased knee physical valgus angle may be a risk factor for patellofemoral pain syndrome.

Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60％participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10％participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.

Objective:To analyze the clinicopathological features of gastric oxyntic gland neo-plasms.Methods:Forty-nine cases of stomach oxyntic gland neoplasms including oxyntic gland adenoma(OGA)and gastric adenocarcinoma of the fundic gland type(GA-FG)diagnosed in the Sec-ond Hospital of Shandong University from January 2016 to December 2020 were selected.The clini cal information,endoscopic appearance,histological features and immunophenotype were analyzed retrospectively,and followed up.Results:Age of the gastric oxyntic gland neoplasm patients ranged from 19 to 83 years old,with an average age of(57.3±2.4)years old.The male-to-female ratio was 24:25.Most of the lesions were located in the gastric body(27/49)and fundus(15/49).There were four endoscopic phenotypes:flat bulging,polypoid,flat and depression.In some lesions,there were dilated dendritic vessels.48 cases were single onset.The mean maximum diameter of lesions was(3.9±0.5)mm(1.0～7.0 mm).Seven cases showed submucosal invasion,and the inva-sion depth was less than 500 μm.The tumor consists of the dense glandular and the glandular con-nects to form a strip shape,which is irregularly branched and labyrinthlike under the microscope.These tumor cells were well differentiated and the morphology was similar to oxyntic gland cells.The chief cells were the predominant cells.The nucleus was mildly enlarged with slight pleomorphism and the mitosis was uncommon.The oxyntic gland neoplasms of the stomach were diffusely posi-tive for Mucin-6(MUC6)(100％)and Pepsinogen Ⅰ(83％),focally positive for H+/K+-ATPase(58％).Conclusions:The stomach oxyntic gland neoplasm is a new histology type with unique clinico-pathological features.The incidence of this neoplasm is low and the prognosis is good but it still needs long-term follow-up.

Objective:To develop and validate a postoperative infection nomogram of hepatitis B-associated hepatocellular carcinoma (HCC) after hepatectomy.Methods:Clinical data of 229 patients with HCC undergoing hepatectomy at the Department of Hepatobiliary Surgery of Tianjin Third Central Hospital from January 2014 to December 2022 were retrospectively analyzed, including 174 males and 55 females, aged (58.2±11.4) years. LASSO regression analysis screened the factors associated with hepatitis B-associated HCC infection after hepatectomy, which were further incorporated into multivariate logistic regression analysis. A nomographic prediction model was established based on the results of multivariate logistic regression analysis. Concordance index (C-index), calibration curve and receiver operating characteristic (ROC) curve were used to evaluate the model, and decision curve analysis (DCA) was used to analyze the clinical applicability of the model. Internal validation of the model was performed using bootstrap method.Results:A total of nine variables were screened as factors associated with the postoperative infections using LASSO regression, including gender, smoking history, body mass index (BMI), serum level of alpha fetoprotein, resection fashion (anatomical or non-anatomical), intraoperative blood loss, surgical method (laparoscopy or open), serum level of creatinine, and postoperative biliary fistula. Multivariate logistic regression analysis showed that BMI, resection fashion, intraoperative blood loss >500 ml, and postoperative biliary fistula were risk factors for postoperative infection (all P<0.05). Based on the above risk factors, a postoperative infection nomogram of hepatitis B-associated HCC after hepatectomy was established. The C-index was 0.839 (95% CI: 0.768-0.910), and the area under ROC curve was 0.853 (95% CI: 0.795-0.912), indicating that the model had a good predictive ability. The calibration curve was basically consistent with the ideal curve. The DCA showed that the model had a good clinical applicability. Internal validation C-index was 0.829 (95% CI: 0.766-0.892). Conclusion:The nomogram based on BMI, surgical resection fashion, intraoperative blood loss >500 ml, and postoperative biliary fistula has a high predictive accuracy and can be used to predict postoperative infections after hepatectomy for HCC.

ObjectiveBased on the quality evaluation experience of "it is better to have a fragrant and strong aroma" summarized by materia medica of past dynasties， the chemical components of Sojae Semen Nigrum（SSN） and Sojae Semen Praeparatum（SSP） were systematically compared and analyzed， and the main fermentation products in different fermentation time were quantitatively analyzed， so as to clarify the transformation law of internal components in the processing process and provide scientific basis for the modern quality control of SSP. MethodUltra performance liquid chromatography-quadrupole tandem time-of-flight mass spectrometry（UPLC-Q-TOF-MS） was used for the structural identification of the chemical constituents of SSN and SSP， and with the aid of Progenesis QI v2.3 software， the negative ion mode was employed for principal component analysis（PCA） pattern recognition， and the data were analyzed with the aid of orthogonal partial least squares-discriminant analysis（OPLS-DA） for two-dimensional data to obtain S-plot， and components with |P|>0.1 were selected as the differential constituents. The contents of isoflavonoids in SSP during fermentation was determined by UPLC， and the samples were taken every 8 h in the pre-fermentation period and every 2 d in the post-fermentation period， and the dynamic changes of isoflavonoid contents in different fermentation stages were analyzed. The contents of amino acids and nucleosides in SSP and SSN from different fermentation stages were quantitatively analyzed by phenyl isothiocyanate（PITC） pre-column derivatization and high performance liquid chromatography（HPLC） gradient elution， and the contribution of flavor substances to the "delicious" taste of SSP was discussed by taste intensity value（TAV）. ResultA total of 19 kinds of differential components were screened out， mainly soybean saponins and isoflavones， and their contents decreased significantly or even disappeared after fermentation. In the pre-fermentation process of SSP， glycoside bond hydrolysis mainly occurred， and isoflavone glycosides in SSN were degraded and converted into the corresponding aglycones， the content of flavor substances such as amino acids increased gradually. In the post-fermentation process， protein degradation mainly occurred， after 8 d of post-fermentation， the content of isoflavones was basically stable， while the total content of amino acids increased by 8-40 times on average. Different amino acids form the special flavor of SSP， such as the TAV of glutamate is always ahead of other flavor substances， and sweet substances such as alanine and valine have made relatively great contributions to SSP. ConclusionBased on the law of constituent transformation， combined with the traditional evaluation index of "fragrant and strong"， it is difficult to control the fermentation degree of SSP by the existing standards in the 2020 edition of Chinese Pharmacopoeia. It is suggested that description of the characteristics of SSP be refined and changed to "fragrant， delicious and slightly sweet"， and at the same time， the post-fermentation index compounds such as glutamic acid， alanine and valine should be added as the quality control indicators of SSP， so as to standardize the production process and improve the quality of SSP.