BACKGROUND:Neuregulin 1 has been shown to be characterized in cell proliferation,differentiation,and vascular growth.Human amniotic mesenchymal stem cells are important seed cells in the field of tissue engineering,and have been shown to be involved in tissue repair and regeneration. OBJECTIVE:To construct human amniotic mesenchymal stem cells overexpressing neuregulin 1 and investigate their proliferation and migration abilities,as well as their effects on wound healing. METHODS:(1)Human amniotic mesenchymal stem cells were in vitro isolated and cultured and identified.(2)A lentivirus overexpressing neuregulin 1 was constructed.Human amniotic mesenchymal stem cells were divided into empty group,neuregulin 1 group,and control group,and transfected with empty lentivirus and lentivirus overexpressing neuregulin 1,or not transfected,respectively.(3)Edu assay was used to detect the proliferation ability of the cells of each group,and Transwell assay was used to detect the migration ability of the cells.(4)The C57 BL/6 mouse trauma models were constructed and randomly divided into control group,empty group,neuregulin 1 group,with 8 mice in each group.Human amniotic mesenchymal stem cells transfected with empty lentivirus or lentivirus overexpressing neuregulin-1 were uniformly injected with 1 mL at multiple local wound sites.The control group was injected with an equal amount of saline.(5)The healing of the trauma was observed at 1,7,and 14 days after model establishment.Histological changes of the healing of the trauma were observed by hematoxylin-eosin staining.The expression of CD31 on the trauma was observed by immunohistochemistry. RESULTS AND CONCLUSION:(1)Human amniotic mesenchymal stem cells overexpressing neuregulin-1 were successfully constructed.The mRNA and protein expression of intracellular neuregulin 1 was significantly up-regulated compared with the empty group(P<0.05).(2)The overexpression of neuregulin 1 promoted the migratory ability(P<0.01)and proliferative ability of human amniotic mesenchymal stem cells(P<0.05).(3)Human amniotic mesenchymal stem cells overexpressing neuregulin 1 promoted wound healing in mice(P<0.05)and wound angiogenesis(P<0.05).The results showed that overexpression of neuregulin 1 resulted in an increase in the proliferative and migratory capacities of human amniotic mesenchymal stem cells,significantly promoting wound healing and angiogenesis.

BACKGROUND:Human periodontal ligament stem cells are potential functional cells for periodontal tissue engineering.However,long-term in vitro culture may lead to reduced stemness and replicative senescence of periodontal ligament stem cells,which may impair the therapeutic effect of human periodontal ligament stem cells. OBJECTIVE:To investigate the effect of oxymatrine on the stemness maintenance and osteogenic differentiation of periodontal ligament stem cells in vitro,and to explore the potential mechanism. METHODS:Periodontal ligament stem cells were isolated from human periodontal ligament tissues by tissue explant enzyme digestion and cultured.The surface markers of mesenchymal cells were identified by flow cytometry.Periodontal ligament stem cells were incubated with 0,2.5,5,and 10 μg/mL oxymatrine.The effect of oxymatrine on the proliferation activity of periodontal ligament stem cells was detected by CCK8 assay.The appropriate drug concentration for subsequent experiments was screened.Western blot assay was used to detect the expression of stem cell non-specific proteins SOX2 and OCT4 in periodontal ligament stem cells.qRT-PCR and western blot assay were used to detect the expression levels of related osteogenic genes and proteins in periodontal ligament stem cells. RESULTS AND CONCLUSION:(1)The results of CCK8 assay showed that 2.5 μg/mL oxymatrine significantly enhanced the proliferative activity of periodontal stem cells,and the subsequent experiment selected 2.5 μg/mL oxymatrine to intervene.(2)Compared with the blank control group,the protein expression level of SOX2,a stem marker of periodontal ligament stem cells in the oxymatrine group did not change significantly(P>0.05),and the expression of OCT4 was significantly up-regulated(P<0.05).(3)Compared with the osteogenic induction group,the osteogenic genes ALP,RUNX2 mRNA expression and their osteogenic associated protein ALP protein expression of periodontal ligament stem cells were significantly down-regulated in the oxymatrine+osteogenic induction group(P<0.05).(4)The oxymatrine up-regulated the expression of stemness markers of periodontal ligament stem cells and inhibited the bone differentiation of periodontal ligament stem cells,and the results of high-throughput sequencing showed that it may be associated with WNT2,WNT16,COMP,and BMP6.

Objective To explore the short-term outcome and safety of 577 nm subthreshold micropulse laser(SML)in the treatment of central serous chorioretinopathy(CSC).Methods The clinical data of 22 patients(24 eyes)with CSC who were admitted to First Affiliated Hospital of Army Medical University from April 2023 to April 2024 were retrospectively analyzed.The 12 eyes had acute CSC,the 12 eyes had chronic CSC,and all of them were treated with SML.The changes of best-corrected visual acuity(BCVA),central macular thickness(CMT),subfoveal choroidal thickness(SFCT),subretinal fluid height(SRFH),and central macular sensitivity(CMS)before treatment and 1 month after treatment were analyzed.The absorption of subretinal fluid 1 month after treatment and related complications were observed.Results Compared with those before treatment,the CMT,SFCT,and SRFH 1 month after treatment significantly declined(P<0.05).The LogMAR BCVA and CMS 1 month after treatment were significantly improved compared with those before treatment(P<0.05).The CMS(r=-0.555,P=0.006)and LogMAR BCVA(r=0.439,P=0.032)before treatment were significantly correlated with SRFH before treatment.The change of SRFH was significantly correlated with CMT before treatment(r=0.616,P=0.001),but without correlation with SFCT before treatment(r=0.168,P=0.431).One month after treatment,11 eyes had complete absorption of subretinal fluid,12 eyes had varying degrees of absorption,and 1 eye had an increase in SRFH.No related adverse reactions were observed.Conclusion The 577 nm SML has a good therapeutic effect on CSC,which can significantly improve the macular structure and central visual function,with good safety.

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 observe the effect of resveratrol(Res)on T-acute lymphoblastic leukemia(T-ALL)mice,and further explore its mechanism on Notch1 signaling pathway.Methods:Twenty-five 6-8 weeks old female C57BL/6 mice were randomly divided into control group,T-ALL group and Res group.Res group was further divided into low-Res.middle-Res and high-Res group.The percentage of leukemia cells in peripheral blood and spleen cell suspension were detected by flow cytometry and Wright-Giemsa staining,pathological morphology of spleen and bone marrow tissues were observed by HE staining,the expression levels of Notch1,Hes-1,c-Myc,miR-19b and PTEN mRNA in spleen tissue were detected by RT-qPCR,and the protein levels of Notch1,Hes-1,c-Myc,p-PTEN and PTEN were detected by Western blot.Results:Compared with control group,the leukemia cells in peripheral blood of mice in T-ALL group were markedly increased,accompanied by diffuse infiltration of leukemia cells in spleen and bone marrow tissues,the mRNA levels of Notch1,Hes-1,c-Myc,miR-19b and the protein levels of Notch1.Hes-1,c-Myc were increased(P＜0.01),while the expression of PTEN mRNA and protein were significantly decreased in the spleen tissue of T-ALL mice(P＜0.01).The above indicators in the H-Res group were reversed compared with T-ALL group after administration of resveratrol.Conclusion:Resveratrol may play a role in anti T-ALL by inhibiting Notch1 signaling pathway in mice.

Objective:To evaluate inflammation early in the infarct zone and its dynamic changes after acute myocardial infarction (AMI) using 18F-FDG PET imaging, and analyze its relationship with left ventricular remodeling progression (LVRP). Methods:Sixteen Bama miniature pigs (4-6 months old, 8 females) were selected. AMI models were established by balloon occlusion of the left anterior descending artery. 18F-FDG PET imaging was performed before AMI and at days 1, 5, 8, and 14 post-AMI to evaluate the regional inflammation response. 18F-FDG SUV ratio (SUVR) and the percentage of uptake area of left ventricle (F-extent) in the infarct zone, and the SUVRs of the spleen and bone marrow, were measured. Echocardiography and 99Tc m-methoxyisobutylisonitrile(MIBI) SPECT myocardial perfusion imaging (MPI) were performed at the above time points and on day 28 post-AMI to assess left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and myocardial perfusion defect extent. The degree of LVRP at day 28 post-AMI was defined as ΔLVESV(%)=(LVESV AMI 28 d-LVESV AMI 1 d)/LVESV AMI 1 d×100%. Data were analyzed using repeated measures analysis of variance, Kruskal-Wallis rank sum test and Pearson correlation analysis. Results:Twelve pigs were successfully modeled and completed the study. Inflammation in the infarct zone persisted until day 14 post-AMI. The SUVR of the infarct zone pre-AMI and at days 1, 5, 8, and 14 post-AMI were 1.03±0.08, 3.49±1.06, 2.93±0.90, 2.38±0.76, and 1.63±0.62, respectively ( F=49.31, P<0.001). The F-extent values in the infarct zone pre-AMI and at days 1, 5, 8, and 14 post-AMI were 0, (40.08±12.46)%, (40.00±12.76)%, (31.08±12.82)%, and 16.50%(7.25%, 22.00%), respectively ( H=37.61, P=0.001). There were no significant differences in the SUVRs of bone marrow and spleen before and after AMI ( F values: 0.69 and 0.77, both P>0.05). At day 1 post-AMI, both SUVR and F-extent in the infarct zone were significantly correlated with LVRP ( r values: 0.82 and 0.70, P values: 0.001 and 0.035). Conclusions:18F-FDG PET imaging can be used to evaluate inflammation in the infarct area and its dynamic changes after AMI. Inflammation in the infarct area is severe at day 1, and then gradually decreases. The extent and severity of inflammation visible on 18F-FDG PET imaging 1 d after AMI are closely related to LVRP.

Objective:To analyze the correlation between body fat distribution measured by quantitative CT (QCT) and body mass index in adults receiving physical examination.Methods:It was a cross-sectional study. From January to December 2021, 3 205 adults undergoing physical examination who met the inclusion criteria and underwent chest CT and QCT examination in the health management discipline of Henan Provincial People′s Hospital were selected as the research objects. The general data were collected; and the subcutaneous fat area, visceral fat area, total abdominal fat area, liver fat content, abdominal obesity and fatty liver detection rate were measured by QCT. According to body mass index, the subjects were divided into normal group (18.5-<24.0 kg/m 2, 1 343 cases), overweight group (24.0-<28.0 kg/m 2, 1 427 cases) and obesity group (≥28.0 kg/m 2, 435 cases). One-way analysis of variance and χ2 test were used to compare the differences of QCT indexes among the three groups. Pearson and Spearman correlation analysis were used to evaluate the correlation between QCT indexes and body mass index. Receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic effect of QCT on obesity and fatty liver. Results:Subcutaneous fat area, visceral fat area, total abdominal fat area, liver fat content, abdominal obesity and fatty liver detection rate in obese group were all significantly higher than those in overweight group and normal group [males, (147.60±46.44) vs (104.33±27.68), (73.46±22.65) cm 2; (297.46±54.70) vs (229.40±53.12), (159.57±49.68) cm 2; (445.06±70.24) vs (333.73±62.91), (233.02±61.87) cm 2; 11.30% (7.90%, 15.55%) vs 8.75% (6.50%, 11.70%), 6.60% (4.80%, 8.70%); 100.0% vs 96.0%, 64.0%; 92.9% vs 86.7%, 73.3%; females, (213.96±48.61) vs (155.85±35.31), (107.24±31.01) cm 2; (185.41±43.88) vs (142.48±41.75), (96.56±36.50) cm 2; (399.37±68.07) vs (298.33±56.86), (203.80±57.53) cm 2; 9.80% (6.90%, 13.30%) vs 7.30% (5.05%, 9.80%), 5.40%(3.50%, 7.20%); 96.4% vs 74.8%, 28.9%; 87.3% vs 75.6%, 56.5%], and were all positively correlated with body mass index (males, r/ rs=0.709, 0.738, 0.831, 0.402, 0.464, 0.225; females, r/ rs=0.798, 0.695, 0.841, 0.416, 0.605, 0.276) (all P<0.001). In both male and female subjects, the detection rates of obesity based on QCT were significantly higher than those based on body mass index (male, 86.9% vs 16.6%; female, 49.3% vs 8.9%), and the detection rates of fatty liver based on QCT were significantly higher than those based on ultrasound (male, 83.6% vs 57.1%; female, 65.2% vs 27.6%) (all P<0.001). ROC curve showed that when the visceral fat area of 142 cm 2 was used as the cut-off value for the diagnosis of obesity in male subjects, the sensitivity and specificity was 100% and 15.8%, respectively; and when the cut-off value of liver fat content 5.0% was used to diagnose fatty liver, the sensitivity and specificity was 88.9% and 25.1%, respectively. When the visceral fat area of 115 cm 2 was set as the cut-off value for the diagnosis of obesity in female subjects, the sensitivity and specificity was 96.4% and 55.3%, respectively; when the liver fat content of 5.0% was set as the cut-off value for the diagnosis of fatty liver, the sensitivity and specificity was 83.7% and 43.2%, respectively. Conclusions:The indexes of abdominal fat and liver fat measured by QCT in adults receiving physical examination are all positively correlated with body mass index. The effect of QCT in the diagnosis of obesity and fatty liver are both better than body mass index and ultrasound.

Objective:To analyze the distribution of body fat with quantitative computed tomography (QCT) in people with normal body mass index (BMI).Methods:A cross-sectional study was conducted in the physical examination population who underwent chest CT and QCT examination in the Department of Health Management, Henan Provincial People′s Hospital from January to December in 2021, and 1 395 physical examination subjects who met the inclusion criteria were selected as the research subjects. The subjects were divided into five groups according to their age. The general data of the subjects were collected. The total abdominal fat area (TFA), visceral fat area (VFA), subcutaneous fat area (SFA), total abdominal muscle area (TMA) and muscle fat content (MFC) in the subjects were measured by QCT. One-way analysis of variance, Welch test and Kruskal-Wallis test were used to compare the above QCT measurement indexes between the two genders among different age groups with normal BMI. Pearson correlation analysis was used to analyze the correlation between VFA and sarcopenia indexes. Multivariate linear regression was used to analyze the relationship between VFA and linear correlation variables in the related indicators of sarcopenia.Results:There were significant differences in TFA, VFA, TMA and SMI among different age groups in subjects with normal BMI (all P<0.05). Pearson correlation analysis showed that VFA was negatively correlated with TMA in some age groups (male: 18-39 years group: r=-0.351; 40-49 years group: r=-0.278; 60-69 years group: r=-0.245; female:40-49 years group: r=-0.251; 50-59 years group: r=-0.270;≥70 years group: r=-0.391; all P<0.01); it was negatively correlated with SMI (male: 18-39 years group: r=-0.352; 40-49 years group: r=-0.340; 50-59 years group: r=-0.266; 60-69 years group: r=-0.316; female: 40-49 years group: r=-0.240; 50-59 years group: r=-0.284; all P<0.001); it was positively correlated with MFC (male: 18-39 years group: r=0.342; 40-49 years group: r=0.291; female: 50-59 years group: r=0.133; 60-69 years group: r=0.284; all P<0.05). Multivariate linear regression analysis showed that VFA was independently and negatively correlated with SMI in both men and women after adjusting for age interference factors (male B=-1.881, t=-6.025, P<0.001; female B=-0.603, t=-2.887, P=0.004), and it was independently positively correlated with MFC (male B=1.230, t=4.271, P<0.001;female B=0.893, t=3.836, P<0.001). There was an independent negative correlation between VFA and TMA in male subjects ( B=0.263, t=2.478, P=0.013). Conclusions:VFA is correlated with TMA, SMI and MFC in people with normal BMI. Regardless of gender, SMI has a negative effect on VFA, and MFC has a positive effect on VFA.

Objective:To investigate the effect of GRIM-19 on the resistance of carcinoma cells to the chemotherapeutic agent docetaxel in the treatment of PCa.Methods:Using siRNA technology to interfere with the gene expression in PCa cells,we estab-lished a model of GRIM-19 overexpression/knockdown in PCa cells.We investigated the effect of different expression levels of GRIM-19 on docetaxel-induced death of the PCa cells by qPCR,Western blot and flow cytometry,and assessed the value of GRIM-19 in re-ducing the chemotherapy-resistance of PCa cells.Results:GRIM-19 was down-regulated in PCa tissues and cells.Knockout of GRIM-19 significantly decreased the expression of siGRIM19 in the PC-3 and LNCaP cells,and reduced their death rate when treated with docetaxel compared with the control group.The expressions of GRIM-19 mRNA and protein were remarkably upregulated after transfection with GRIM-19,and the overexpressed GRIM-19 promoted the death of the PC-3 and LNCaP cells treated with docetaxel in a dose-dependent manner.Flow cytometry analysis showed a lower apoptosis rate of PC-3-R cells than that of PC-3 cells at different time points of docetaxel-induction at different doses.Conclusion:GRIM-19 is a PCa suppressor gene with a significant facilitating effect on the apoptosis of PCa cells,and the overexpression of GRIM-19 promotes docetaxel-induced PCa cell death and improves the sensitivity of chemotherapy.

Objective To study the effects of dual-hemispheric transcranial direct current stimulation(Dual-tDCS)on upper limb motor function in chronic-phase stroke patients to provide theoretical references for neural mechanisms-based treatment of upper limb dysfunction.Methods Totally 24 chronic-phase stroke patients with upper limb motor dysfunction were selected from some hospital and divided into an experimental group(n=13)and a control group(n=11)the random number table.The control group was treated with tDCS pseudo-stimulation combined with conventional rehabilitation,while the experimental group was given with Dual-tDCS combined with conventional rehabilitation.The patient activities were assessed before and after treatment with Fugl-Meyer assessment upper limb scale(FMA-UL)and activities of daily living(ADL)scale.The changes of primary motor cortex(M1 area)and whole brain functional connectivity(FC)were compared before and after treatment.SPSS 24.0 statistical software was used for data analysis.Results After treatment,the two groups both had the FAM-UL and ADL scores increased significantly,and the experimental group had the scores statistically higher than those of the control group,and the differences were all statistically significant(P＜0.05).In the control group,the analysis on M1 area and whole brain FC after treatment indicated the FC decreased from M1 area at the unaffected side to midoccipital gyrus at the affected side and lingual gyrus and healthy angular gyrus at the unaffected side;there were no brain areas with changed FC found(P＜0.01).In the experimental group,the FC was lowered from M1 area at the unaffected side to cerebellum and cerebellar vermis at the unaffected side,while raised to precentral gyrus at the affected side(P＜0.01);the FC ascended from M1 area at the affected side to cerebellum and middle temporal gyrus at the affected side,while declined to precentral gyrus at the unaffected side(P＜0.01).Conclusion The neuromodulatory effect of Dual-tDCS on the brain improves FC in motor and non-motor-related brain areas in chronic-phase stroke patients,and may contribute to rehabilitation of upper limb motor dysfunction in chronic-phase stroke.[Chinese Medical Equipment Journal,2024,45(2):67-73]