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 understand the surveillance situation of poliovirus in Guangzhou from 2011 to 2024, and to further strengthen polio surveillance and ensure the continued maintenance of a polio-free status. Methods An analysis was conducted on the discovery and investigation results of six cases of vaccine-derived poliovirus (VDPV) detected in Guangzhou. Results A total of 6 VDPV incidents were reported in Guangzhou from 2011 to June 2024, among which 5 incidents were from sewage sample testing in the Liede Sewage Treatment Plant in Guangzhou, all of which were confirmed as VDPV, with 1 for type I, 1 for type II, and 3 for type III. In addition, one confirmed HFMD case was identified as a type VDPV II carrier. No presence of any wild poliovirus (WPV), VDPV cases, or circulating VDPV (cVDPV) was reported. Conclusion Guangzhou City has maintained a high level of vigilance and effectiveness in the monitoring and prevention of polio. Continuously strengthening the construction of the polio monitoring network, optimizing vaccination strategies, and comprehensively improving public health awareness are still the focus of the prevention and control work in the future.

Background Diesel engines are widely used in transportation, agriculture, construction, industry, and other fields. Diesel exhaust, classified as a Group 1 carcinogen, emits particles (DEP) that can penetrate deep into the respiratory tract, posing significant health risks. DEP pollution is particularly severe in confined environments, necessitating effective control measures. Objective Under laboratory simulation conditions, to explore the spatiotemporal distribution characteristics of the mass and number concentrations of DEP as it diffuses indoors and to reveal the effects of ventilation and additional airflow on indoor DEP pollution levels. Methods A diesel engine was placed in a laboratory (length 3.39 m × width 2.85 m × height 2.4 m) with its exhaust emitted from east to west. An air purifier was installed 1 m south of the engine. Eight measurement points (1 m horizontal distance from the exhaust outlet, height: 1 m/1.5 m) were setup to monitor DEP concentrations using portable laser particle sizers. The effects of engine power (4.05 kW vs. 5.15 kW), ventilation (maximum airflow: 600 m³·h⁻¹), additional airflow intensity (low and high), and direction (forward/reverse) on DEP pollution were analyzed. DEP levels of 5 diesel vehicle models were also compared. Results The mass and number concentrations of DEP indoors increased immediately after the diesel engine started. The peak mass concentration time at the eastern measurement point (−1, 0) m opposite to the exhaust direction (17.70 min) was significantly longer than that at the western (1, 0) m (16.20 min), southern (0, -1) m (14.45 min), and northern (0, 1) m (12.70 min) points (P<0.05), with no significant differences between the other points (western, southern, and northern) (P>0.05). The northern point (0, 1) m exhibited the highest DEP mass and number concentration peaks (174.62 μg·m⁻³, 1319.85 p·cm⁻³), significantly exceeding those at the southern (0, −1) m (129.89 μg·m⁻³, 1175.24 p·cm⁻³), eastern (−1, 0) m (140.12 μg·m⁻³, 1120.53 p·cm⁻³), and western (1, 0) m (147.60 μg·m⁻³, 818.62 p·cm⁻³) points (P<0.05), and no significant differences were observed among other points (P>0.05). There were no significant differences in peak DEP mass and number concentrations by measurement heights (P>0.05). Diesel engine power, ventilation, airflow intensity, and airflow direction had no significant effect on the time of peak DEP concentration (P>0.05). However, higher engine power (5.15 kW) produced greater DEP peaks [(186.66±19.29) μg·m⁻³, (1382.79±122.56) p·cm⁻³] than the 4.05 kW engine power [(168.41±12.65) μg·m⁻³, (1284.45±71.30) p·cm⁻³] (P<0.05). The peak mass concentration [(342.04±35.03) μg·m⁻³] and number concentration [(1886.87±57.91) p·cm⁻³] of DEP in the non-ventilated group were significantly higher than those in the ventilated group [(186.66±19.29) μg·m⁻³, (1382.79±122.56) p·cm⁻³] (P<0.001). Forward airflow elevated DEP mass concentrations compared to reverse airflow (287.71 μg·m⁻³ vs. 243.74 μg·m⁻³, t=−2.592, P=0.009), but no effects on DEP number concentration (P>0.05). Significant differences in mass concentration were observed among selected 5 vehicle models (Z=38.109, P<0.001). Conclusion The operation of diesel engines will emit a large amount of particulate matter, causing pollution in enclosed spaces. Diesel engines with greater power have higher levels of DEP pollution emissions. Based on the spatiotemporal distribution characteristics, it is recommended to set the operation position in the reverse direction of exhaust emissions and close to air purifiers, while avoiding the use of additional air flow equipment.

Umbilical cord mesenchymal stem cells (UC-MSCs) have been widely used in regenerative medicine, but there is limited research on the stability of UC-MSCs formulation during production. This study aims to assess the stability of the cell stock solution and intermediate product throughout the production process, as well as the final product following reconstitution, in order to offer guidance for the manufacturing process and serve as a reference for formulation reconstitution methods. Three batches of cell formulation were produced and stored under low temperature (2-8 ℃) and room temperature (20-26 ℃) during cell stock solution and intermediate product stages. The storage time intervals for cell stock solution were 0, 2, 4, and 6 h, while for intermediate products, the intervals were 0, 1, 2, and 3 h. The evaluation items included visual inspection, viable cell concentration, cell viability, cell surface markers, lymphocyte proliferation inhibition rate, and sterility. Additionally, dilution and culture stability studies were performed after reconstitution of the cell product. The reconstitution diluents included 0.9% sodium chloride injection, 0.9% sodium chloride injection + 1% human serum albumin, and 0.9% sodium chloride injection + 2% human serum albumin, with dilution ratios of 10-fold and 40-fold. The storage time intervals after dilution were 0, 1, 2, 3, and 4 h. The reconstitution culture media included DMEM medium, DMEM + 2% platelet lysate, 0.9% sodium chloride injection, and 0.9% sodium chloride injection + 1% human serum albumin, and the culture duration was 24 h. The evaluation items were viable cell concentration and cell viability. The results showed that the cell stock solution remained stable for up to 6 h under both low temperature (2-8 ℃) and room temperature (20-26 ℃) conditions, while the intermediate product remained stable for up to 3 h under the same conditions. After formulation reconstitution, using sodium chloride injection diluted with 1% or 2% human serum albumin maintained a viability of over 80% within 4 h. It was observed that different dilution factors had an impact on cell viability. After formulation reconstitution, cultivation in medium with 2% platelet lysate resulted in a cell viability of over 80% after 24 h. In conclusion, the stability of cell stock solution within 6 h and intermediate product within 3 h meets the requirements. The addition of 1% or 2% human serum albumin in the reconstitution diluent can better protect the post-reconstitution cell viability.

Objective To study the application of CE-Chirp in the evaluation of hearing impairment in forensic medicine by testing the auditory brainstem response(ABR)in adults using CE-Chirp to ana-lyze the relationship between the V-wave response threshold of CE-Chirp ABR test and the pure tone hearing threshold.Methods Subjects(aged 20-77 with a total of 100 ears)who underwent CE-Chirp ABR test in Changzhou De'an Hospital from January 2018 to June 2019 were selected to obtain the V-wave response threshold,and pure tone air conduction hearing threshold tests were conducted at 0.5,1.0,2.0 and 4.0 kHz,respectively,to obtain pure tone listening threshold.The differences and statistical differences between the average pure tone hearing threshold and V-wave response threshold were compared in different hearing levels and different age groups.The correlation,differences and statistical differences between the two tests at each frequency were analyzed for all subjects.The lin-ear regression equation for estimating pure tone hearing threshold for all subjects CE-Chirp ABR V-wave response threshold was established,and the feasibility of the equation was tested.Results There was no statistical significance in the CE-Chirp ABR response threshold and pure tone hearing threshold dif-ference between different hearing level groups and different age groups(P>0.05).There was a good correlation between adult CE-Chirp ABR V-wave response threshold and pure tone hearing threshold with statistical significance(P<0.05),and linear regression analysis showed a significant linear correla-tion between the two(P<0.05).Conclusion The use of CE-Chirp ABR V-wave response threshold can be used to evaluate subjects'pure tone hearing threshold under certain conditions,and can be used as an audiological test method for forensic hearing impairment assessment.

Important forensic diagnostic indicators of sudden death in coronary atherosclerotic heart dis-ease,such as acute or chronic myocardial ischemic changes,sometimes make it difficult to locate the ischemic site due to the short death process,the lack of tissue reaction time.In some cases,the de-ceased died of sudden death on the first-episode,resulting in difficulty for medical examiners to make an accurate diagnosis.However,clinical studies on coronary instability plaque revealed the key role of coronary spasm and thrombosis caused by their lesions in sudden coronary death process.This paper mainly summarizes the pathological characteristics of unstable coronary plaque based on clinical medi-cal research,including plaque rupture,plaque erosion and calcified nodules,as well as the influencing factors leading to plaque instability,and briefly describes the research progress and technique of the atherosclerotic plaques,in order to improve the study on the mechanism of sudden coronary death and improve the accuracy of the forensic diagnosis of sudden coronary death by diagnosing different patho-logic states of coronary atherosclerotic plaques.

Objective To explore the effect of omeprazole combined with different probiotics on regulating intestinal flora in reducing functional dyspepsia(FD)in children.Methods Two hundreds children with FD admitted to the Pediatric Department of Foshan Maternal and Child Health Hospital from January 2022 to February 2023 were se-lected as the study subjects.They were randomly divided into omeprazde(omep)group,groups of omeprazole+yeast(yeast group),+clostridium butyricum(clos group),and+bifidobacterium(bifi group)respectively.Results After treatment,serum level of IL-6,TNF-α,IL-1β,hs-CRP,VIP,SS,Enterobacter and Enterococcus in all groups significantly decreased as compared with the finding before treatment(P<0.05).Those targets in the three combined treatment groups were significantly lower compared to the ome group;After treatment,the serum MOT level,bifidobacteria,and lactobacilli in each group were significantly increased(P<0.05),and the results from three combined treatment groups demonstrated notably higher levels compared to the omep group(P<0.05);The scores of symptoms in all groups showed a significant alleviation after the treatment(P<0.05).Additionally,the three combined treatment groups exhibited significantly lower symptom scores than the group treated with omeprazole alone(P<0.05).There was no difference in the incidence of adverse reactions during treatment among the groups.Conclusions Omeprazole combined with different probiotics have achieved good results in the treatment of FD in children.

Objective:To explore the mechanism of miR-30e-5p inhibiting the invasion and migration of hepatoma cells by targeting phosphoinositide-3-kinase catalytic delta polypeptide(PIK3CD)-mediated phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of the rapamycin(mTOR)signaling pathway.Methods:HepG2 cells were divided into control group,miR-30e-5p mimics group,PIK3CD knockdown group,negative control group,and miR-30e-5p mimics+PIK3CD overexpression group by transfecting the corresponding plasmids,the expression of miR-30e-5p,PIK3CD and PI3K/AKT/mTOR signaling pathway was detected by qRT-PCR and Western blot;the proliferation rate of Hep G2 cells in each group was detected by CCK-8 method;cell migration and invasion were measured by cell scratch test and Transwell test;the expression of matrix metalloproteinase(MMP)2,MMP9,E-cadherin,N-cadherin,Vimentin in Hep G2 cells of each group were detected by Western blot.The targeting regulation of miR-30e-5p on PIK3CD in Hep G2 cells was detected by double luciferase report assay.Results:Compared with the control group,the proliferation rate,migration rate,invasion number,the expression of N-cadherin,MMP2 and MMP9 proteins,the expression of PIK3CD protein and mRNA,p-P13K/PI3K,p-AKT/AKT,and p-mTOR/mTOR in the miR-30e-5p mimics group and PIK3CD knockdown group were lower(P＜0.05),the expression of E-cadherin protein was higher(P＜0.05).Overexpression of PIK3CD attenuates the inhibitory effects of miR-30e-5p mimics on proliferation,migration and invasion of hepatocellular carcinoma cells and elevates the expression of PI3K/AKT/mTOR pathway-related proteins;miR-30e-5p targets down-regulation of PIK3CD expression.Conclusion:Up-regulation of miR-30e-5p can prevent PI3K/AKT/mTOR signal activation by decreasing the expression of PIK3CD,thereby inhibiting the proliferation,migration and invasion of hepatocellular carcinoma cells.

Objective To describe and analyze the current situation of the four same type of departments in an hospital in order to provide a reference for the construction of"the most cost-effective medical care".Methods The CN-DRG were used to automatically group and compare the medical capacity and inpatient service efficiency of the hospital department groups,and in the refined analysis,one DRG disease group of in situ cancer and non-malignant disease loss uterine surgery and single species uterine fibroid was included,and the Kruskal-Wallis H test was used to further compare the differences in length of stay and various costs.Results It included a total of 22630 patients,whose weights varied from a maximum of 3948.62 in diagnostic group 1 to a minimum of 133.55 in diagnostic group 11.The cost consumption indexes ranged from a minimum of 0.89 in diagnostic group 5 to a maximum of 1.04 in diagnostic group 2,while the time consumption indexes ranged from a minimum of 0.48 in diagnostic group 11 to a maximum of 0.81 in diagnostic group 5.When comparing the diagnostic groups,there were statistically significant differences(P＜0.05)in hospitalization days,total cost,diagnostic cost,therapeutic cost,and cost of supplies.Specifically,when comparing the diagnostic and treatment groups within departments,the differences in hospitalization days and all costs were statistically significant(P＜0.05)in departments 1 and 2,the differences in diagnostic cost,therapeutic cost,and cost of supplies were statistically significant(P＜0.05)in department 3.Conclusion There exists a notable disparity in the extent to which each diagnostic and treatment group contributes to the hospital's service capacity and cost variability.Consequently,it is necessary to reasonably evaluate the length of hospital stay and medical cost of patients to achieve the highest cost-effective medical treatment.

Objective:To investigate the current situation of the use of transjugular intrahepatic portosystemic shunt (TIPS) for portal hypertension, which should aid the development of TIPS in China.Methods:The China Portal Hypertension Alliance (CHESS) initiated this study that comprehensively investigated the basic situation of TIPS for portal hypertension in China through network research. The survey included the following: the number of surgical cases, main indications, the development of Early-TIPS, TIPS for portal vein cavernous transformation, collateral circulation embolization, intraoperative portal pressure gradient measurement, commonly used stent types, conventional anticoagulation and time, postoperative follow-up, obstacles, and the application of domestic instruments.Results:According to the survey, a total of 13 527 TIPS operations were carried out in 545 hospitals participating in the survey in 2021, and 94.1% of the hospital had the habit of routine follow-up after TIPS. Most hospitals believed that the main indications of TIPS were the control of acute bleeding (42.6%) and the prevention of rebleeding (40.7%). 48.1% of the teams carried out early or priority TIPS, 53.0% of the teams carried out TIPS for the cavernous transformation of the portal vein, and 81.0% chose routine embolization of collateral circulation during operation. Most of them used coils and biological glue as embolic materials, and 78.5% of the team routinely performed intraoperative portal pressure gradient measurements. In selecting TIPS stents, 57.1% of the hospitals woulel choose Viator-specific stents, 57.2% woulel choose conventional anticoagulation after TIPS, and the duration of anticoagulation was between 3-6 months (55.4%). The limitation of TIPS surgery was mainly due to cost (72.3%) and insufficient understanding of doctors in related departments (77.4%). Most teams accepted the domestic instruments used in TIPS (92.7%).Conclusions:This survey shows that TIPS treatment is an essential part of treating portal hypertension in China. The total number of TIPS cases is far from that of patients with portal hypertension. In the future, it is still necessary to popularize TIPS technology and further standardize surgical indications, routine operations, and instrument application.