Objective To evaluate the rabbit modle of frozen shoulder induced by persistent strain injuries and ice com-pression.Methods Twelve clean,healthy male New Zealand rabbits with a mass of(2 500±500)g were selected and randomly divided into a blank group and a control group with 6 rabbits in each group.In the control group,the rabbits were modeled with persistent strain injuries and ice compression,the general conditions of the rabbits and the active and passive activities of the shoulder joint were observed and their body weights were recorded.MRI was performed on the affected shoulder joints at 6 d and 29 d after modelling to observe the fluid and soft tissue;HE staining was used to observe the morphology of the rabbit bi-ceps longus tendon and the synovial membrane of the joint capsule;Masson staining was used to observe the fibrous deposits of the rabbit biceps longus tendon and the synovial membrane of the joint capsule,and the fibrous deposits were analysed semi-quantitatively by Image J software.Results Six days after the end of modeling,the active movement of the shoulder joints in the control group was limited,the passive movement was not significantly limited,and they walked with a limp;29 days after the end of the modeling,the active and passive movements of the shoulder joints in the model group were severely limited.Com-pared with the blank group(2.50±0.14)kg,the body weight of the model group(2.20±0.17)kg was significantly reduced(P＜0.01).MRI showed that 6 days after modelling,the muscles around the shoulder joint were not smooth in shape,the joint cap-sule structure was narrowed and a large amount of fluid was seen in the joint cavity;29 days after modelling,the muscles around the shoulder joint were rough in shape,structure of the joint capsule was unclear and the fluid in the joint cavity was reduced compared with 6 days after modelling.Pathological staining showed that the long-headed biceps tendon fibres in the control group were disorganised,curled or even broken,and the synovial tissue of the joint capsule was heavily vascularised,with col-lagen fibre deposits and severe inflammatory cell infiltration.The fiber deposition of the long head of biceps brachii in the mod-el group[(23.58±3.41)％,(27.56±3.70)％]and synovial tissue[(41.78±5.59)％,(62.19±7.54)％]were significantly higher than those in the blank group[(1.79±1.03)％,(1.29±0.63)％]at 7 and 30 days after modeling and synovial tissue fiber de-position[(8.15±3.61)％,(11.29±7.10)％],as shown by the semi-quantitative analysis of Masson staining results by Image J software.And the longer the time,the more severe the fibrosis(P＜0.01).Conclusion The behavioral,imaging and pathological findings showed that the rabbit frozen shoulder model with persistent strain injuries and ice compression is consistent with the clinical manifestations and pathogenesis of periarthritis,making it an ideal method for periarthritis research.

Objective:To disclose phylogenetic and antigenic characteristics of hemagglutinin (HA) gene of influenza B virus (Victoria) (BV) in the 2023-2024 influenza surveillance season in Beijing, and understand the matching with influenza vaccine component strain.Methods:Pharyngeal swab specimens from influenza like-illness (ILI) in the 2023-2024 influenza surveillance season were collected from surveillance network labs in Beijing and BV strains were isolated through MDCK or chicken embryo culture. After extracting nucleic acid, HA gene was amplified and sequenced. The nucleotide and amino acid sequence identity were conducted and the maximum likelihood method in Mega 5.0 software was used to construct the phylogenetic tree of HA gene. N-glycosylation sites of HA were performed online. Furthermore, three-dimensional structure of HA was available from SWISS-MODEL homologous modeling. Hemagglutination inhibition (HI) tests were performed to analyze antigenic characteristics of HA of BV strains.Results:Fifty-four BV strains were randomly selected to be analyzed further. Compared with the HA gene of this influenza season vaccine strain (B/Austria/1359417/2021), there are three amino acid mutations among all BV strains, two of which are located in two different antigenic determinants. Furthermore, the phylogenetic tree analysis revealed that only one subgroup of 1A.3a.2 was circulating simultaneously. All BV strains are located in Clade 1A.3a.2 subgroup, and in the same subgroup with that of the vaccine component BV strain in 2023-2024. All BV strains have the same glycosylation sites as that of the vaccine component BV strain in 2023-2024. Antigenic analysis showed that all BV strains were antigenically similar with its vaccine strain.Conclusions:In the 2023-2024 influenza surveillance season, the prevalent BV strains in the population in Beijing city are located in Clade 1A. 3a. 2 subgroup. The antigen matching between BV epidemic strains and vaccine BV components is relatively high during this surveillance season.

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.

Objective:To investigate the effect of genetic polymorphism of MTHFR C677T (rs1801133) on methotrexate (MTX) related toxicity in pediatric mature B-cell lymphoma patients. Methods:Fifty-eight intermediate and high risk patients under 18 years of age with mature B-cell lymphoma who received 5 g/m2 MTX (24 h intravenous infusion) in Sun Yat-sen University Cancer Center from August 2014 to December 2021 were included,and their toxicity of high-dose MTX (HD-MTX) were monitored and analyzed. Results:Among the 58 pediatric patients,the number of CC,CT,and TT genotypes for MTHFR C677T was 33,19 and 6,respectively. A total of 101 courses of HD-MTX therapy were counted,of which plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion were observed in 35 courses,≤0.2 μmol/L in 66 courses. Inter-group comparison showed that plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion increased the risk of developing oral mucositis (P<0.05). Compared with wild-type (CC genotype),patients in the mutant group (CT+TT genotype) were more likely to develop myelosuppression,manifested as anemia,leucopenia,neutropenia and thrombocytopenia. However,plasma MTX level at 48 h was not associated with MTHFR C677T gene polymorphism. Conclusion:The risk of developing oral mucositis in children with mature B-cell lymphoma is associated with plasma MTX concentration. Polymorphism of MTHFR C677T gene is not related to plasma MTX concentration in children with mature B-cell lymphoma,but is related to grade Ⅲ to Ⅳ hematological toxicity.

Objective To develop a portable collection device of human exhaled breath condensate(EBC)based on natural breathing to meet the needs for rapid screening of human respiratory tract(especially lower respiratory tract)infections.Methods The device consisted of a refrigeration unit,a heat dissipation unit and a condensation unit.The refrigeration unit adopted a TES1-7102 thermoelectric Peltier cooler semiconductor as the refrigeration element;the heat dissipation unit was composed of a high thermal conductivity aluminum heat sink and a high-speed brushless cooling fan;the condensation unit was made up of a cold guide plate and a condenser,in which the cold guide plate was made of thin sheet of aluminum alloy,and the condenser was prepared by 3D printing technology and made of hydrophobic polylactic acid,with primary and secondary 2-stage guide grooves and an ultra-thin condensing surface.The performance of the device was verified in terms of cooling,thermal conductivity,condensation and human EBC collection and content analysis.Results Performance analysis showed that after refrigeration began the temperature difference between the condenser surface and the exhaled gas met the requirements of the condenser,and no obvious thermal resistance was found on the condensing surface so that large droplets could be formed rapidly and then be collected after the gas-liquid phase change of the exhaled gas on the condensing surface.Human EBC collection and content analysis indicated the device realized home self-collection of EBCs from people of all ages,and the concentrations of interleukins,C-reactive protein and other inflammation-related indexes and the pH value of the collected EBC samples were all correlated with respiratory infections in the subjects.Conclusion The device developed with easy operation avoids the discomfort of blowing collection and the risk of saliva contamination,and is worthy promoting for rapid diagnosis and dynamic monitoring of respiratory tract infection and other related diseases.[Chinese Medical Equipment Journal,2024,45(8):32-37]

Objective To explore the effects of M1 polarization of microglia on secondary damage in the thalamus after cerebral cortical infarction.Methods A focal cortical infarct model of adult male SD rats was pre-pared using eletrocoagulation and randomized into Sham and model groups at different time points 1～4 weeks after surgery.Based on the assessment of neurofunctional changes in each group of rats,immunohistochemistry was used to observe the number and morphology of NeuN,GFAP and Iba-1 positive cells in(Ventral posterior nucleus of thalamus,VPN)of the ipsilateral thalamus after distal middle cerebral artery occlusion(dMCAO).Immunofures-cence was used to detect the number and morphology of M1 microglia marker(Iba-1+/CD68+cells)and M2 microg-lia marker(Iba-1+/CD206+cells)in VPN of the ipsilateral thalamus after dMCAO.Western blot was used to detect the expression levels of IL-1β,TNF-α,IL-10 and Arg-1 in VPN of the ipsilateral thalamus after dMCAO.Results The results of immunohistochemistry showed a significant decrease in NeuN positive cells and an increase in the density of GFAP and Iba-1 in the ipsilateral VPN of rats after dMCAO when compared with Sham group(P<0.001).Compared with sham group,the protein levels of TNF α and IL-1β were elevated in the ipsilateral VPN elevated(P<0.05).In addition,the model group rats exhibited higher Bederson scores,beam-walking test and adhesive removal test scores after dMCAO compared with Sham group(P<0.05).The numbers of M1 microglia marker(Iba-1+/CD68+cells)were significantly increased when compared with M2 microglia marker(Iba-1+/CD206+cells)in ipsilateral VPN of rats after dMCAO.Conclusion M1 polarization of microglia may play an essential role in secondary damage of thalamus after cerebral cortical infarction.

AIM:To investigate the effects of sodium hydrosulfide(NaHS)on hexokinase 2(HK2)-nucleo-tide-binding oligomerization domain-like receptor protein 3(NLRP3)-gasdermin D(GSDMD)pathway and pyroptosis in-duced by lung ischemia/reperfusion(I/R)in rats.METHODS:Male Sprague-Dawley rats were divided into 6 groups:control group,control+NaHS group,I/R group,low-dose NaHS+I/R(L+I/R)group,medium-dose NaHS+I/R(M+I/R)group,and high-dose NaHS+I/R(H+I/R)group,with 6 rats in each group.The NaHS was administered via intraperi-toneal injection at 1.5 mL,30 min before modeling.The left lung tissues were collected 30 min after ischemia and 1 h af-ter reperfusion,and the wet/dry weight ratio and total lung water content were recorded.Hematoxylin-eosin(HE)staining was used to examine lung tissue morphological changes.The levels of malondialdehyde(MDA),myeloperoxidase(MPO)and lactate in lung tissues were measured with test kits.ELISA was employed to determine the levels of interleukin-1β(IL-1β)and IL-18.The expression of glycolysis-and pyroptosis-related indicators was analyzed by Western blot,qRT-PCR and immunofluorescence staining.RESULTS:Compared with control group,the rats in NaHS group showed no signifi-cant differences in all laboratory tests(P>0.05).The rats in I/R group exhibited significant lung injury,oxidative stress,increased lactate level,and up-regulated glycolysis and pyroptosis(P<0.05 or P<0.01).Compared with I/R group,the indicators in L+I/R group showed a downward trend(P<0.01)or no difference(P>0.05),while those in M+I/R group dis-played a significant reduction(P<0.05 or P<0.01).However,the indexes in H+I/R group exhibited no significant dif-ferences in these tests(all P>0.05).CONCLUSION:A moderate dose(56 μmol·L-1·kg-1)of NaHS mitigated the oc-currence of pyroptosis by inhibiting the HK2-NLRP3-GSDMD pathway,thus contributing to the attenuation of lung I/R in-jury in rats.

Objective:To explore the risk factors related to delayed pleural effusion in multiple trauma patients.Methods:A retrospective cohort study was conducted to analyze the clinical data of 145 multiple trauma patients admitted to the First Affiliated Hospital of Soochow University from January 2022 to October 2023, including 99 males and 46 females, aged 18-81 years [56.0(46.5, 64.5)years]. Based on whether delayed pleural effusion developed after injury, the patients were divided into delayed pleural effusion group ( n=66) and non-delayed pleural effusion group ( n=79). The clinical data of the patients in both groups were collected, including gender, age, underlying disease (diabetes mellitus and hypertension), cause of injury (traffic injury, blow injury, fall from height, and others), comorbid injuries (traumatic brain injury, maxillofacial fracture, clavicular fracture, scapular fracture, sternal fracture, spinal fracture, multiple rib fracture, pneumothorax, lung contusion, and pelvic fracture), severity of injury [injury severity score (ISS) and abbreviated injury scale (AIS) score for the chest], location and number of rib fractures, vital signs at admission (body temperature, heart rate, respiration, systolic blood pressure, diastolic blood pressure), and clinical test indices [white blood cells (WBC), hemoglobin (Hb), platelets (PLT), total protein (TP), albumin (ALB), C-reactive protein (CRP), procalcitonin (PCT), fibrinogen (FIB), fibrin degradation product (FDP), D-dimer (D-D), aspartate transaminase (AST), alanine transferase (ALT), and creatinine (Cr)]. Univariate analysis was conducted to assess the correlation between the forementioned factors and the development of delayed pleural effusion after multiple traumas. Multivariate Logistic regression analysis was used to determine the independent risk factors for the development of delayed pleural effusion after multiple traumas. Results:The results of univariate analysis showed that multiple rib fracture, pneumothorax, pulmonary contusion, chest AIS score, posterior rib fracture, number of rib fractures, TP, ALB, CRP, PCT and FDP were correlated with delayed pleural effusion in multiple trauma patients ( P<0.05 or 0.01); whereas gender, age, underlying disease, cause of injury, sternal fracture, spinal fracture, clavicular fracture, scapular fracture, pelvic fracture, maxillofacial fracture, traumatic brain injury, anterior rib fracture, ISS, vital signs at admission, WBC, Hb, PLT, FIB, D-D, AST, ALT, and Cr were not correlated with delayed pleural effusion in multiple trauma patients ( P>0.05). The results of multivariate Logistic regression analysis revealed that lung contusion ( OR=3.96, 95% CI 1.59, 9.85, P<0.01), ALB ( OR=0.79, 95% CI 0.66, 0.94, P<0.01), and CRP ( OR=1.02, 95% CI 1.01, 1.03, P<0.01) were significantly correlated with delayed pleural effusion in multiple trauma patients. Conclusion:Lung contusion, ALB, and CRP are the independent risk factors for delayed pleural effusion in multiple trauma patients.

The incidence of osteoporotic thoracolumbar vertebral fracture (OTLVF) in the elderly is gradually increasing. The kyphotic deformity caused by various factors has become an important characteristic of OTLVF and has received increasing attention. Its clinical manifestations include pain, delayed nerve damage, sagittal imbalance, etc. Currently, the definition and diagnosis of OTLVF with kyphotic deformity in the elderly are still unclear. Although there are many treatment options, they are controversial. Existing guidelines or consensuses pay little attention to this type of fracture with kyphotic deformity. To this end, the Lumbar Education Working Group of the Spine Branch of the Chinese Medicine Education Association and Editorial Committee of Chinese Journal of Trauma organized the experts in the relevant fields to jointly develop Clinical guidelines for the diagnosis and treatment of osteoporotic thoracolumbar vertebral fractures with kyphotic deformity in the elderly ( version 2024), based on evidence-based medical advancements and the principles of scientificity, practicality, and advanced nature, which provided 18 recommendations to standardize the clinical diagnosis and treatment.

Objective To analyze the prevalence and genetic characteristics of influenza A(H3N2) viruses in the city of Xiangyang in 2022-2023, and to provide a scientific basis for predicting the epidemic and mutation of influenza virus. Methods Throat swab specimens of the influenza like cases were collected from national influenza monitoring sentinel hospitals in Xiangyang every week. RNA was extracted from the specimens for influenza diagnosing using real-time RT-PCR．Viruses were isolated from H3N2 positive specimens, and HA and NA genes were amplified and sequenced．3D modeling analyses were conducted. Results The gene phylogenetic tree showed that the H3N2 isolates in 2022-2023 belonged to 3C.2a1b.2a1 and 3C.2a1b.2a2 branches, respectively. The A(H3N2) influenza virus strains all had amino acid point mutation sites on important antigenic determinants of HA protein. The epitope mutations of the 2022 A(H3N2) strain mainly occurred in regions B, C, and D. The epitope mutations of the A(H3N2) strain in 2023 mainly occurred in regions C and D. Different glycosylation sites of HA gene were found in 2022-2023 strains. No variation was found in key amino acid sites associated with neuraminidase inhibitor resistance. The difference of overall structure was not obvious in the three-dimensional simulation structure diagram. Conclusion The A(H3N2) influenza strains isolated in this study have shown antigenic drift, especially the mutation of HA, which may affect the protective effect of the vaccine on the local population and lead to influenza epidemic. The variations of HA and NA suggest that close attention should be paid to the epidemic and genetic variation of H3N2 subtype influenza virus, to provide a scientific basis for the selection of influenza virus vaccine strains and the prevention and control of influenza.