ObjectiveNeuroinflammation plays a crucial role in both the onset and progression of ischemic stroke, exerting a significant impact on the recovery of the central nervous system. Excessive neuroinflammation can lead to secondary neuronal damage, further exacerbating brain injury and impairing functional recovery. As a result, effectively modulating and reducing neuroinflammation in the brain has become a key therapeutic strategy for improving outcomes in ischemic stroke patients. Among various approaches, targeting immune regulation to control inflammation has gained increasing attention. This study aims to investigate the role of in vitro induced regulatory T cells (Treg cells) in suppressing neuroinflammation after ischemic stroke, as well as their potential therapeutic effects. By exploring the mechanisms through which Tregs exert their immunomodulatory functions, this research is expected to provide new insights into stroke treatment strategies. MethodsNaive CD4⁺ T cells were isolated from mouse spleens using a negative selection method to ensure high purity, and then they were induced in vitro to differentiate into Treg cells by adding specific cytokines. The anti-inflammatory effects and therapeutic potential of Treg cells transplantation in a mouse model of ischemic stroke was evaluated. In the middle cerebral artery occlusion (MCAO) model, after Treg cells transplantation, their ability to successfully migrate to the infarcted brain region and their impact on neuroinflammation levels were examined. To further investigate the role of Treg cells in stroke recovery, the changes in cytokine expression and their effects on immune cell interactions was analyzed. Additionally, infarct size and behavioral scores were measured to assess the neuroprotective effects of Treg cells. By integrating multiple indicators, the comprehensive evaluation of potential benefits of Treg cells in the treatment of ischemic stroke was performed. ResultsTreg cells significantly regulated the expression levels of both pro-inflammatory and anti-inflammatory cytokines in vitro and in vivo, effectively balancing the immune response and suppressing excessive inflammation. Additionally, Treg cells inhibited the activation and activity of inflammatory cells, thereby reducing neuroinflammation. In the MCAO mouse model, Treg cells were observed to accumulate in the infarcted brain region, where they significantly reduced the infarct size, demonstrating their neuroprotective effects. Furthermore, Treg cell therapy notably improved behavioral scores, suggesting its role in promoting functional recovery, and increased the survival rate of ischemic stroke mice, highlighting its potential as a promising therapeutic strategy for stroke treatment. ConclusionIn vitro induced Treg cells can effectively suppress neuroinflammation caused by ischemic stroke, demonstrating promising clinical application potential. By regulating the balance between pro-inflammatory and anti-inflammatory cytokines, Treg cells can inhibit immune responses in the nervous system, thereby reducing neuronal damage. Additionally, they can modulate the immune microenvironment, suppress the activation of inflammatory cells, and promote tissue repair. The therapeutic effects of Treg cells also include enhancing post-stroke recovery, improving behavioral outcomes, and increasing the survival rate of ischemic stroke mice. With their ability to suppress neuroinflammation, Treg cell therapy provides a novel and effective strategy for the treatment of ischemic stroke, offering broad application prospects in clinical immunotherapy and regenerative medicine.

Objective To quantitatively evaluate the association of short-term exposure to ambient submicron particulate matter (PM₁) with hospital admissions for angina in older adults. Methods A case-crossover study was conducted among 46 687 older adults hospitalized for angina from 2016 to 2019 in Guangzhou medical institutions. Grid data on ambient PM₁ concentrations in Guangzhou were obtained from the ChinaHighAirPollutants (CHAP) dataset. Exposure to PM₁ was assessed according to each subject's residential addresses. Conditional logistic regression model was used to analyze the the exposure-response association between PM₁ and hospital admissions for angina. Results From 2016 to 2019, the average exposure level of PM₁ on the same day of hospital admissions (lag 0) for angina was 21.0 ± 11.5 μg/m³. The results of main model analysis showed that lag 0 day exposure to ambient PM₁ was significantly associated with a higher odds of hospital admissions for angina in older adults. Each 10 μg/m³ increase of PM₁ exposure level was significantly associated with a 1.31% (95% CI: 0.05%, 2.59%) increased odds of angina admissions. Results from a two-pollutant model adjusting for O₃ showed that the association between short-term exposure to PM₁ and odds of hospitalization for angina remained stable. According to the results of the above model, it was estimated that the excess hospitalization attributable to ambient PM₁ exposure accounted for 2.46% (95% CI: 0.09%, 4.76%) of the total admissions in Guangzhou during 2016-2019, corresponding to 1539 (95% CI: 54, 2976) admissions. No significant effect modification on the associations was observed by sex, age, or season. Conclusion Short-term exposure to ambient PM₁ was significantly associated with an increased odds of hospital admissions for angina in older adults.

Objective To investigate the effect of microglia activation regulated by C-X3-C motif chemokine ligand 1(CX3CL1)-C-X3-C motif chemokine receptor 1(CX3CR1)pathway on memory function in hemorrhagic shock/resuscitation rats.Methods The experiment was divided into two parts.In the first part,the rats were randomly divided into sham group,model-0.5 hour group,model-1.5 hour group,model-3 hour group,10 rats in each group.There were differences in the time of hemorrhagic shock among each group.In the second part,rats were randomly divided into control group and CX3CL1 group,10 rats in each group.The rats in CX3CL1 group were treated with CX3CL1 protein factor(intraventricular injection),and the rats in control group were treated with saline.All rats were trained in Morris water maze experiments before model construction,and tests of Morris water maze experiments were carried out after 4 days of model construction.After completion,the whole brains were taken for HE staining and immunohistochemical staining.Cerebrospinal fluid was taken for detection of inflammatory cytokines,and hippocampus tissues were taken for Real-time PCR detection and Western blotting detection.Results Compared with the sham group,the escape latency of rats in model group increased,the number of platform crossings and the resident time in the third quadrant decreased.The neuronal state was impaired in HE staining in model group.In addition,compared with the sham group,the expression of ionized calcium binding adaptor molecule-1(Iba1)in the brain of the rats in model group increased,the contents of tumor necrosis factor-α(TNF-α)and interleukin(IL)-6 in the cerebrospinal fluid increased,and the M1-type microglia markers CD16,TNF-α,IL-1β and inducible nitric oxide synthase(iNOS)mRNA content increased.At the same time,compared with the sham group,the expressions of CX3CL1 and CX3CR1 in the brain of model group decreased,and the expressions of phosphorylated nuclear factor-κB(p-NF-κB)and nucleotide binding oligomerization domain(NOD)-like receptor protein 3(NLRP3)increased.However,compared with the control group,rats in CX3CL1 group had reduced escape latency,increased platform crossing times and quadrantⅢresident time,and recovered neuronal states.In addition,the expression of Iba1 in the brain of CX3CL1 group decreased,the contents of TNF-α and IL-6 in the cerebrospinal fluid decreased,the mRNA contents of M1-type microglia markers like CD16,TNF-α,IL-1β and iNOS decreased,and the mRNA contents of markers of M2-type microglia glial like CD206,transforming growth factor-β(TGF-β),arginase-1(Arg1),Chitinase 3-like protein 1(Ym 1)increased.Conclusion CX3CL1 can help inhibit the excessive activation of microglia,induce the polarization of microglia to M2 type,inhibit the polarization of M1 type,reduce the release of inflammatory cytokines,and alleviate the memory function damage induced by hemorrhagic shock/resuscitation.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective:To investigate the correlation between the levels of CC chemokine ligand 2 (CCL2) and periostin (POSTN) in serum and alveolar lavage fluid of patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) complicated with respiratory virus infection and lung function.Methods:From March 2020 to March 2023, 96 patients with acute exacerbation of COPD admitted to our hospital were collected. Among them, 34 patients with concurrent respiratory virus infection were included in the infected group, and 62 patients without respiratory virus infection were included in the uninfected group. Enzyme linked immunosorbent assay (ELISA) was applied to detect the expression levels of CCL2 and POSTN in serum and alveolar lavage fluid. Pearson method was applied to analyze the correlation between CCL2 and POSTN levels in serum and alveolar lavage fluid of infected patients and lung function indicators.Results:The levels of CCL 2 ( t=12.633, 9.253 2, 2) and POSTN ( t=12.370, 7.383) were significantly increased in the infected group compared with the uninfected group ( P<0.05). Compared with the uninfected group, the 6-minute walking test (6 MWT), peak expiratory flow rate (peak expiratory flow, PEF), forced expiratory volume at the first second (forced expiratory volume in one second, FEV 1), and the forced lung capacity (forced vital capacity, FVC), FEV 1/FVC, and maximum middle breath mean flow rate (maximal mid-expiratory flow curve, MMEF) were significantly lower ( t=14.141, 24.165, 22.421, 21.223, 5.278, 29.456, P<0.05). Correlation analysis showed that the levels of CCL2 and POSTN in the serum and alveolar lavage fluid of the infected group were negatively correlated with the levels of 6MWT, PEF, FEV1, FVC, FEV1/FVC, and MMEF ( P<0.05). Conclusions:CCL2 and POSTN levels were highly expressed in serum and alveolar lavage fluid of patients with respiratory virus infection during acute exacerbation of COPD, which were closely related to lung function.

Objective To design a storage device for lymph node specimens of gynecological malignant tumors and to evaluate its application effect.Methods The specimen depository is composed of 3 parts,including storage frame,partition plate and marking plate.391 patients with gynecological malignant tumor surgeries requiring collection of retroperitoneal lymph nodes were selected in the operating room of a tertiary A hospital in Zhejiang Province from January to December 2022 in accordance with the operation schedule.They were randomly divided into an experimental group(n=196)and a control group(n=195).Patients in the experimental group used a newly developed storage device,while the control group was with traditional device.The incidence of additional verification specimens by doctors,the average time for disposing of lymph node specimens,and the job satisfaction survey of doctors and nurses were compared.Results Within a period of 12 months after utilizing this easily recognizable specimen storage device,the additional verification rate in the experimental group was 10.62％compared with the rate of 72.48％in the control group.The average time of disposing lymph node specimens was reduced from(8.3±0.9)to(5.2±0.3)minutes.Doctors and nurses in the experimental group reported a higher level of satisfaction for the specimen storage device(P＜0.05).Conclusion Utilizing the newly designed specimen storage device can help medical staff to alleviate their workload,enhance their work efficiency,raise their job satisfaction,and ensure the accuracy of pathological results.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

The breakage pattern of unit particles during the production of oral solid dosage forms (OSD) is closely related to the quality of intermediate or final products. To accurately characterize the particles and study the evolution law of particle breakage, the Bonding model of the discrete element method (DEM) was used to investigate the breakage patterns of model parameters, particle shape and process conditions (loading mode and loading rate) on the dynamic breakage, force-time curve, breakage rate, maximum breakage size ratio and fracture strength of particles. The results showed that the particle breakage force was positively correlated with normal strength and bonded disk scale, negatively correlated with normal stiffness per unit area and tangential stiffness per unit area, and weakly correlated with tangential strength. The particle breakage rate was negatively correlated with the aspect ratio of the particles, and the maximum breakage size ratio was positively correlated with the aspect ratio of the particles; among the three loading modes, the breakage rate of compression breakage model was the largest, the breakage rate of shear breakage model was the second largest, and the breakage rate of wear breakage model was the smallest; the maximum breakage size ratio was positively correlated with the loading rate, the loading mode and the loading rate had no mutual influence on particle breakage rate, but had mutual influence on the maximum breakage size ratio. The research results will provide a theoretical basis for the shift of OSD from batch manufacturing to advanced manufacturing.

The adulteration and counterfeiting of herbal ingredients in medicinal and food homology (MFH) have a serious impact on the quality of herbal materials, thereby endangering human health. Compared to pharmaceutical drugs, health products derived from traditional Chinese medicine (TCM) are more easily accessible and closely integrated into consumers' daily life. However, the authentication of the authenticity of TCM ingredients in MFH has not received sufficient attention. The lack of clear standards emphasizes the necessity of conducting systematic research in this area. This study utilized DNA barcoding technology, combining ITS2, psbA-trnH, matK as universal barcode sequences, and DX, HH, JYH as specific barcode sequences, to identify the authenticity of commercial medicinal and food homology scented herbal teas. The aim was to investigate the authenticity of scented herbal tea products circulating in the market. The research results revealed that among 180 scented herbal tea samples, DNA barcodes were successfully obtained from 164 samples, while the remaining samples either lacked the target components or suffered severe DNA degradation, resulting in failed amplification. Combined with morphological identification studies, it was found that out of the 180 samples, 141 were authentic, accounting for 78.33% of the total samples, while 31 samples showed adulteration and 8 samples lacked the target components, accounting for 21.67% of the total samples. Additionally, water testing revealed that 5 samples of Carthamus tinctorius herbal tea exhibited the phenomenon of weight adulteration. This study exposed the presence of adulteration and weight adulteration in scented herbal tea products, highlighting the need for regulatory authorities to expedite the establishment of quality standards in scented herbal tea industry. These findings provide valuable insights for the rapid development of the scented herbal tea industry.

Objective To apply a COMSOL-based finite element analysis method to investigating the electric field effects produced by the human lower limb musculoskeletal system under the synergistic effects of stress field and electromagnetic field.Methods Firstly,a 3D human body model was constructed by Maxon Cinema 4D R21 software,and then imported into COMSOL 6.1 software in STL format.Secondly,an electromagnetic field intervention and stress loading model for the left lower limb of the human body was designed and constructed,in which 15 Hz quasi-pulse group current signals were used for electromagnetic field excitation and the stress field was realized by applying a vibration load with an average compressive force of about 90 N/cm2 to the left foot of the human body.Finally,the electromagnetic properties of human tissue were simulated by numerical simulation,and then the effects of stress field or elecromagnetic field or combined stress field and electromagnetic field on human bioelectric field were compared.Results Simulation results showed that the electric field intensity peaked at the leg joints under both electromagnetic and stress fields acting alone or synergistically,the bioelectric field intensity generated by the human body was related to the distance from the exogenous excitation loading location,and the electric field generated under synergistic action was equivalent to the linear superposition of the bioelectric field in the tissue induced by the electromagnetic field and the stress field acting alone.Conclusion Data supplement is provided for predicting bioelectric field changes within the musculoskeletal tissue,and theoretical foundation is laid for the development and application of multi-physics field synergistic intervention therapy for treating the disorders of the lower limb musculos-keletal system.[Chinese Medical Equipment Journal,2024,45(9):21-26]