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.

Aim To design and synthesize a series of phenylacetamide derivatives with different substituted phenylacetic acid as raw materials,and to investigate the protective effects of the compound on the damage of pancreatic β cells induced by palmitate acid(PA).Methods Min6 cells were cultured and divided into B blank control group,PA treatment group and PA+compounds group.The viability of Min6 cells was de-tected by CCK-8.The protein expressions of TXNIP and NLRP3 were observed by Western blot.MDA con-tent and SOD activity were detected by MDA and SOD kit.The insulin secretion of Min6 islet cells was meas-ured with insulin ELISA kit.Results A total of 10 phenylacetamide derivatives were designed and synthe-sized.Their structures were confirmed by 1H NMR and ESI-MS.Pharmacological activity study showed that most of the compounds had protective effects on islet βcells,among which LY-6 and LY-8 had stronger pro-tective effects than PA model group,with the cell via-bility of 61.4％,and LY-6 had the highest cell activi-ty,reaching to 104.9％.Compared with PA group,the protein expression of TXNIP and NLRP3 decreased in LY-6 and LY-8 groups,MDA content decreased and SOD activity increased,and insulin secretion of Min6 cell increased.Conclusions LY-6 and LY-8 inhibit TXNIP expression and decrease the activation of NL-RP3 inflammasome,and decrease the production of MDA and increase SOD activity,and thus reducing is-let β cells apoptosis and increasing insulin secretion.Therefore,the compound LY-6 could serve as a poten-tial anti-diabetic new chemical entity.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

AIM To study the phenylpropanoids from Brandisia hancei Hook.f.and their antioxidant activities.METHODS The extract from B.hancei was isolated and purified by Rp-C18,MCI,semi-preparative HPLC,silica gel and Sephadex LH-20,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The cytotoxicities was determined by MTT method,and the antioxidant activities were determined by DPPH and ABTS+free radical scavenging methods.RESULTS Fifteen phenylpropanoids were isolated and identified as(+)-pinonesinol(1),(-)-medioresinol(2),(-)-syringaresinol(3),buddlenol D(4),(7R,7'R,7″S,8S,8'S,8″S)-4',5″-dihydroxy-3,5,3',4″-tetramethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'-sesquineo-lignan-7″,9″-diol(5),(-)-(7R,7'R,7″R,8S,8'S,8″S)-4',4″-dihydroxy-3,3',3″,5-tetramethoxy-7,9':7',9-diepoxy-4,8″-oxy-8,8'-sesquineolignan-7″,9″-diol(6),hedyotol A(7),dracunculifoside R(8),acteoside(9),isoacteoside(10),arenarioside(11),isomartynoside(12),curcasinlignan B(13),erythro-2,3-bis(4-hydroxy-3-methoxyphenyl)-3-ethoxypropan-l-ol(14),citrusin C(15).Compounds 1-4 and 9-10 had no obvious cytotoxicity to HepG2 hepatoma cells.Compounds 1,3,9,10 and 12 had strong scavenging activities against DPPH radicals.Compounds 1-3,9-10,12 and 14 showed strong scavenging activities against ABTS+radical.CONCLUSION Compounds 1-8 and 12-15 are isolated from genus Brandisia for the first time.The phenylpropanoids from B.hancei show strong antioxidant activities.

Objective:To explore the treatment methods and clinical efficacy of penetrating high-voltage electric burns to thoracoabdominal wall.Methods:This study was a retrospective observational study. From March 2020 to March 2023, six male patients with penetrating high-voltage electric burns to thoracoabdominal wall who met the inclusion criteria were hospitalized at West China Hospital of Sichuan University, aged 42 to 57 years. Among them, one patient had thoracoabdominal wall defects with perforation and necrosis of the gastric wall and diaphragm, two patients had thoracoabdominal wall defects with perforation and necrosis of the gastric wall alone, and three patients had abdominal wall defects with perforation and necrosis of the small intestine. In the emergency department, aesthetic plastic and burn surgery, general surgery, and/or thoracic surgery doctors jointly formulated an emergency surgery plan for the patients. Three patients with perforation and necrosis of the gastric wall underwent subtotal gastrectomy and anastomosis. One of them, who also had diaphragmatic perforation and necrosis, underwent resection of the necrotic diaphragm and repair. The other three patients with perforation and necrosis of the small intestine underwent resection and anastomosis of the necrotic intestinal segment. After debriding the thoracoabdominal wall wounds conservatively in stage Ⅰ and repairing the abdominal wall defects with greater omentum coverage, the thoracoabdominal wall wounds were treated with vacuum sealing drainage (VSD). Seven days later, a stage Ⅱ thorough debridement of the thoracoabdominal wall wounds was performed, and bovine acellular dermal matrix was transplanted onto the surface of the greater omentum and the surrounding skin wounds without skin coverage, and the VSD treatment of the thoracoabdominal wall wounds was continued. After 7 days, the VSD treatment was stopped, and after the fresh granulation tissue well developed in the wounds, a stage Ⅲ transplantation of meshed split-thickness skin graft from the lateral femur was performed to close the thoracoabdominal wall wounds, followed by continuing VSD treatment for another 7 days. Data were recorded including the status of patients' enteral nutrition recovery and occurrence of complications such as abdominal infection after stage Ⅰ surgery, the time from starting moist dressing change to the wound being ready for skin grafting after stage Ⅱ surgery, the microbiological culture of wound exudate samples and conditions of wound surrounding areas from starting moist dressing change to wound healing after stage Ⅱ surgery, skin graft survival, and wound healing time. Follow-up was carried out to observe the occurrence of gastrointestinal symptoms, abdominal wall hernia, scars, and functional disorders, etc.Results:All six patients resumed enteral nutrition on day 2 to 4 after stage Ⅰ surgery, with no occurrence of intestinal obstruction, anastomotic leakage, or abdominal infection. The time from starting moist dressing change to the wound being ready for skin grafting after stage Ⅱ surgery was 8 (6, 12) days. During the period from starting moist dressing change to wound healing after stage Ⅱ surgery, microbiological culture of wound exudate sample showed Enterobacter cloacae in one patient and Pseudomonas aeruginosa in another patient, while the remaining four patients had negative cultures; no patient developed wound edge inflammation. All grafted skin survived, and the wound healing time was 38 (30, 46) days. During follow-up from 12 to 36 months after stage Ⅲ surgery, patients had no intractable constipation or intestinal obstruction symptoms, no obvious local tissue herniation requiring surgical treatment, no scar ulceration, and no functional disorders. Conclusions:For penetrating high-voltage electric burns to thoracoabdominal wall, a sequential three-stage surgical treatment plan under a multidisciplinary team collaboration model can effectively protect organ function and control wound infection. Long-term follow-up shows good gastrointestinal function and thoracoabdominal wall appearance. This method is highly reproducible and effective, which is suitable for clinical promotion and use.

Objective To design a pressure reading system for splinting distal radius fractures to enable real-time monitoring of splint fixation pressure.Methods A pressure reading system for splinting distal radius fractures was developed with the components of a main contrl unit,a pressure and temperature acquisition unit and a power management unit.The main control unit had a STC15 series SCM as the main control chip,and the pressure and temperature acquisition unit was realized with a FSR400 thin film pressure sensor and a DS18B20 digital temperature measurement chip.The software of the system was developed with C language.The system developed was used to test the magnitude and distribution of the pressure on the splints by applying loads on the fixation straps at 90°,60° and 30° directions to the willow splint and 3D printing splint,respectively,with the total mass of the loads increased from 600 g to 1 200 g and each test repeated by 6 times.Results The system developed was capable of collecting the pressure values at real time and showed them on the display screen.The maximum pressure always occurred at the the connection between the fixation straps and the edge of the splints and the middle parts of the splints were subject to relatively low pressure in case of different loads,when the fixation straps were 90°,60° and 30° to the willow splint and 3D printing splint respectively.The maximum pressure on the willow splint was(239.17±4.49)g when the fixation strap was 90° to the splint and loaded with 1 200 g;the minimum pressure on the willow splint was(89.83±17.38)g when the fixation strap was 60° to the splint and loaded with 600 g.The maximum pressure on the 3D printing splint was(177.67±21.77)g when the fixation strap was 90° to the splint and loaded with 1 100 g;the minimum pressure was(66.50±3.02)g for the 3D printing splint when the fixation strap was 30° to the splint and loaded with 600 g.Conclusion The ssystem developed can read pressure values of the splint under different loads and angles,and the 3D printing splint behaves better than the willow splint in the evenness of pressure distribution.Theoretical references are provided for quantitative clinical treatment with splint fixation.[Chinese Medical Equipment Journal,2024,45(8):44-50]

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Aim To express and purify recombinant hCGH-CTP fusion protein in high-density suspension culture of Chinese hamster ovary cells (CHO-S), and to verify the lipid accumulation effect of rhCGH-CTP on 3T3-L1 mature adipocytes. Methods The recombinant protein expression vector (pcDNA3. 1-rhCGH-CTP) was constructed, achieved by fusing the human glycoprotein hormone beta 5/alpha 2 cDNA with CTP Linker. The expression plasmid was transiently transfected into the suspended CHO-S to express rhCGH-CTP protein and then purified, and the protein biological activity was verified. Intervention with 3T3-L1 mature adipocyte cells for 24 h was performed to detect the changes of intracellular triglyceride (TG) level. Results Western blot results showed that rhCGH-CTP protein was successfully expressed in CHO-S cells, and the yield was up to 715. 4 mg • L~ . The secreted protein was purified by AKTA pure system with higher purity that was up to 90% as identified by SDS-PAGE. In addition, the intracellular cAMP content of mature adipocytes with high expression of TSHR gene significantly increased after intervention with different concentrations of rhCGH-CTP protein by ELISA kit, indicating that rhCGH-CTP protein had biological activity. Oil red 0 staining showed that compared with the control group, the lipid content of mature adipocytes in the intervention groups with different concentrations of rhCGH-CTP protein significantly decreased (P < 0. 05) . Conclusions The rhCGH-CTP protein has been successfully expressed and purified with biological activity, and effectively reduce TG. This research provides an important theoretical basis for further revealing the physiological role of CGH protein and its potential application in clinical practice.

Objective The volume and cortical thickness of gray matter in patients with multiple sclerosis (MS) and neuromyelitis optica (NMO) were compared and analyzed by voxel⁃based morphometry (VBM) and surface⁃based morphometry (SBM), and the differences in the structural changes of gray matter in the two diseases were discussed. Methods A total of 21 MS patients, 16 NMO patients and 19 healthy controls were scanned by routine MRI sequence. The data were processed and analyzed by VBM and SBM method based on the statistical parameter tool SPM12 of Matlab2014a platform and the small tool CAT12 under SPM12. Results Compared with the normal control group (NC), after Gaussian random field (GRF) correction, the gray matter volume in MS group was significantly reduced in left superior occipital, left cuneus, left calcarine, left precuneus, left postcentral, left central paracentral lobule, right cuneus, left middle frontal, left superior frontal and left superior medial frontal (P<0. 05). After family wise error (FWE) correction, the thickness of left paracentral, left superiorfrontal and left precuneus cortex in MS group was significantly reduced (P<0. 05). Compared with the NC group, after GRF correction, the gray matter volume in the left postcentral, left precentral, left inferior parietal, right precentral and right middle frontal in NMO group was significantly increased (P<0. 05). In NMO group, the volume of gray matter in left middle occipital, left superior occipital, left inferior temporal, right middle occipital, left superior frontal orbital, right middle cingulum, left anterior cingulum, right angular and left precuneus were significantly decreased (P<0. 05). Brain regions showed no significant differences in cortical thickness between NMO groups after FWE correction. Compared with the NMO group, after GRF correction, the gray matter volume in the right fusiform and right middle frontal in MS group was increased significantly(P<0. 05). In MS group, the gray matter volume of left thalamus, left pallidum, left precentral, left middle frontal, left middle temporal, right pallidum, left inferior parietal and right superior parietal were significantly decreased (P<0. 05). After FWE correction, the thickness of left inferiorparietal, left superiorparietal, left supramarginal, left paracentral, left superiorfrontal and left precuneus cortex in MS group decreased significantly (P<0. 05). Conclusion The atrophy of brain gray matter structure in MS patients mainly involves the left parietal region, while NMO patients are not sensitive to the change of brain gray matter structure. The significant difference in brain gray matter volume between MS patients and NMO patients is mainly located in the deep cerebral nucleus mass.

Objective To investigate the clinical efficacy and safety of Yiqi Huatan Tongluo Prescription(mainly composed of Fici Simplicissimae Radix,Notoginseng Radix et Rhizoma,Pinelliae Rhizoma Praeparatum,Poria,Nelumbinis Folium,and Glycyrrhizae Radix et Rhizoma,etc.)combined with drug-coated balloon(DCB)in the treatment of coronary heart disease(CHD)and to observe its effect on low-shear related serological indicators.Methods A total of 106 patients with CHD of qi deficiency and phlegm stasis obstructing collateral type who were scheduled to undergo percutaneous coronary intervention were randomly divided into a treatment group and a control group,with 53 cases in each group.The control group was treated with drug-eluting stent implantation,and the treatment group was treated with DCB.After the operation,the control group was given conventional antiplatelet aggregation drugs,and the treatment group was given oral administration of Yiqi Huatan Tongluo Prescription.The medication for the two groups lasted for 12 weeks.The changes in the serum levels of monocyte chemoattractant protein 1(MCP-1),interleukin 1 β(IL-1β)and vascular endothelial growth factor(VEGF)in the two groups were observed before and after treatment.Moreover,the traditional Chinese medicine(TCM)syndrome efficacy after treatment and the incidence of adverse events one year after operation were compared between the two groups.Results(1)After 12 weeks of treatment,the total effective rate for TCM syndrome efficacy of the treatment group was 88.68％(47/53),and that of the control group was 75.47％(40/53).The intergroup comparison(tested by chi-square test)showed that the TCM syndrome efficacy in the treatment group was significantly superior to that in the control group(P＜0.05).(2)The analysis of indicators related to endothelial dysfunction in the blood flow with low shear stress showed that after treatment,the levels of serum MCP-1,IL-1βand VEGF in the control group presented no obvious changes(P＞0.05),but the serum levels of MCP-1 and IL-1β in the treatment group were significantly lowered compared with those before treatment(P＜0.05).The intergroup comparison showed that the decrease of serum MCP-1,IL-1β and VEGF levels in the treatment group was significantly superior to that in the control group(P＜0.05).(3)The one-year follow-up after the operation showed that the total incidence of adverse events in the treatment group was 18.87％(10/53),and that in the control group was 20.75％(11/53).There was no significant difference between the two groups(P＞0.05).Conclusion Yiqi Huatan Tongluo Prescription combined with DCB has definite action on the targets related to endothelial dysfunction in coronary blood flow with low shear stress,which is conducive to reducing inflammatory response,improving the symptoms of angina pectoris and enhancing clinical efficacy.The incidence of adverse events did not increase one year after operation,indicating good safety and effectiveness.