AIM:To observe the effect of folic acid(FA)on C2C12 myoblast proliferation and differentia-tion,and to explore its mechanism.METHODS:During the proliferation stage,C2C12 myoblasts were treated with vari-ous concentrations of FA(0,2.5,5,10 and 20 μmol/L).The cell status was observed under a microscope,cell viability was detected using the MTT method,and cell proliferation was assessed using the EdU method.In the differentiation stage,C2C12 cells were divided into control(Ctrl)group(0 μmol/L FA)and FA group(10 μmol/L FA).On day 2 or 4 of differentiation,immunofluorescence staining and Western blot were employed to detect the expression of myoblast differen-tiation-related proteins,myoblast determination protein 1(MyoD),myogenin(MyoG)and myosin heavy chain(MyHC).The myotubule formation in each group was analyzed.On day 4 of differentiation,C2C12 cells were treated with FA for 0,1,3 and 6 h,and the protein levels of p-JNK,JNK,p-p38 MAPK and p38 MAPK at each time point were detected by Western blot.Additionally,C2C12 cells after 4-day differentiation were divided into Ctrl group,FA group,FA+ SP600125(specific inhibitor of JNK)group,and FA+SB203580(specific inhibitor of p38)group.The cells in FA+ SP600125 and FA+SB203580 groups were treated with 10 μmol/L SP600125 or SB203580 for 1 h,followed by treatment with 10 μmol/L FA for 24 h.The cells in FA group were treated with 10 μmol/L FA for 24 h,while the cells in Ctrl group were left untreated.The protein levels of p-JNK,JNK,p-p38 MAPK,p38 MAPK and MyHC were detected by Western blot.RESULTS:(1)Compared with 0 μmol/L FA group,the number of the cells in other concentration groups in-creased,cell viability was raised(P＜0.05 or P＜0.01),and the rate of EdU positive cells increased(P＜0.05).(2)Com-pared with Ctrl group,the expression levels of MyoD,MyoG and MyHC in FA group were increased(P＜0.05),and the myotube fusion index was raised(P＜0.05 or P＜0.01).(3)Compared with 0 h group,the ratios of p-JNK/JNK and p-p38 MAPK/p38 MAPK were elevated after FA treatment for 1,3 and 6 h(P＜0.05 or P＜0.01),and showed a trend of gradual increase with the extension of treatment time.(4)After FA treatment,the ratios of p-JNK/JNK and p-p38 MAPK/p38 MAPK,and the expression of MyHC were elevated(P＜0.01).Treatment with SP600125 decreased the ratio of p-JNK/JNK and the expression of MyHC(P＜0.05),while SB203580 intervention cut down the ratio of p-p38 MAPK/p38 MAPK and the expression of MyHC(P＜0.05 or P＜0.01).CONCLUSION:Folic acid can promote the differentiation of C2C12 myoblasts by activating the JNK/p38 MAPK signaling pathway.

Objective To discuss the application of the"rotating guidewire and correcting the filter recovery hook direction technique"("rotation-correction loop technique"for short),a technique invented by the authors in clinical practice,in the retrieval of complex inferior vena cava filter(IVCF),and to discuss its technical skills and advantages.Methods The clinical data of 417 patients carrying an IVCF,who were admitted to the Department of Vascular Surgery of Second Hospital of Shanxi Medical University of China to retrieve IVCF between January 2022 and December 2022,were retrospectively analyzed.Taking the time spent on the retrieval of IVCF and the intraoperative radiation dose as the evaluation indicators,the advantages and disadvantages of the standard filter retrieval technique,the"rotation-correction loop technique"and the other loop-assisted techniques were compared.Results Both the intraoperative radiation dose and the time spent on the retrieval of IVCF using"rotation-correction loop technique"were remarkably lower than those of other loop-assisted techniques(P＜0.000 1).Conclusion For the retrieval of complex IVCF,especially for the IVCF which is heavily tilted and/or its recovered hook is attached to the vascular wall,the use of"rotation-correction loop technique"can shorten the time spent on the the retrieval of IVCF and reduce the intraoperative radiation dose.This technique carries high safety and practicability,the device is simple and it can be manipulated by single physician,which is conducive to clinical application and promotion.(J Intervent Radiol,2024,33:289-294)

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 compare the therapeutic effects of manual reduction and machine reduction in patients with benign paroxysmal positional vertigo(BPPV)at different ages.Methods Randomly select 300 patients clinically diagnosed with BPPV who visited the Hearing Center of the First Affiliated Hospital of Wenzhou Medical University from April 2022 to December 2023.They were divided into young and middle-aged group of 170 cases(18-59 years old)and elderly group of 130 cases(≥60 years old)according to age.Each group was further divided equally into experimental group and control group based on the diagnosis and treatment methods adopted by the patients.The experimental group patients were treated with a benign paroxysmal positional vertigo diagnosis and treatment system(model/specification:SRM-Ⅳ)for machine reduction.The control group patients were treated with manual reduction.Compare the effective rate of reduction,reduction frequency,incidence of residual dizziness symptoms,and duration of each group.Results In young and middle-aged patients,the incidence and duration of residual dizziness symptoms after reduction in experimental group were significantly lower than those in control group(P<0.05),and there was no statistically significant difference in the effective rate and number of reductions(P>0.05).In elderly group,the reduction efficiency of experimental group was significantly higher than that of control group,and the reduction frequency was lower than that of the control group(P<0.05).There was no statistically significant difference in the incidence and duration of residual dizziness symptoms after reduction(P>0.05).Conclusion Machine reduction can significantly improve the reduction efficiency of elderly BPPV patients,significantly shorten the duration of residual dizziness after reduction treatment in young and middle-aged patients,and reduce its incidence.

Objective:To identify species type and analyze the homology of Brucella in a family cluster infection. Methods:Two patients with brucellosis from the same family who were treated at the First People's Hospital of Lianyungang City, Jiangsu Province in May 2022 were selected as the research subjects. Brucella strains (H4LYG01 and H2LYG02) were isolated through blood culture. The isolated strains were identified for species type and homology analysis using a fully automated microbial mass spectrometry detection system. Molecular typing of the isolated strains was performed using multiple locus variable-number tandem-repeat analysis (MLVA) and multilocus sequence typing (MLST). Results:H4LYG01 and H2LYG02 were both Brucella Maltese, and the credibility scores were 9.745 and 9.627, respectively, and the homology was 100%. The MLVA results showed that the gene loci of H4LYG01 and H2LYG02 were completely identical, with the same genotype. The MLST results showed that the sequence type (ST) of H4LYG01 and H2LYG02 were both ST8 types. Conclusion:The two isolated strains of Brucella from a family with clustered infections are both Brucella Maltese and from the same source.

Objective:To explore the feasibility of using ultrasonic convex array probe compressing abdominal wall to increase success rate of external cephalic version (ECV) without anesthesia in full-term and near-term pregnancy.Methods:Totally 190 singleton and non‐cephalic presentation pregnant women in 36-39 +4 weeks of gestation performed ECV from April 2019 to August 2023 in the First Affiliated Hospital of Nanjing Medical University were analyzed. According to whether use the ultrasound probe compressing fetal breech or not, the pregnant women were divided into two groups: 81 cases in the probe-compressing group (including primipara 61 cases and multipara 20 cases) and 109 cases in the non-probe-compressing group(including primipara 72 cases and multipara 37 cases). Clinical data, ECV related factors and complications were analyzed and compared between the two groups. Results:(1) The overall success rate of ECV was 64.2% (122/190). There was no significant difference in the success rate of ECV between probe-compressing group and non-probe-compressing group [69.1% (56/81) vs 60.6% (66/109), χ2=1.490, P=0.222]. The total vaginal delivery rate after successful ECV was 81.1% (99/122), while 71.1% (54/76) in primipara and 97.8% (45/46) in multipara, respectively. (2) Compare to the non-probe-compressing group, the success rate of ECV in primipara was significantly higher in the probe-compressing group [45.8% (33/72) vs 70.5% (43/61)], but the gestational age was shorter and the height was higher in the probe-compressing group (all P<0.05). The success rate of ECV of multipara in the probe-compressing group (65.0%, 13/20) was lower than that in the non-probe-compressing group (89.2%, 33/37), but there was no significant difference between the two groups ( P>0.05). (3) Multivariate logistic regression analysis showed that abdominal wall compressed by ultrasound probe ( OR=2.601, 95% CI: 1.113-6.075; P=0.027) and amniotic fluid index (AFI; OR=1.010, 95% CI: 1.001-1.020; P=0.028) were positive factors for the successful rate of ECV in primipara pregnant women. (4) The main complication of ECV was transient fetal heart rate reduction (8.9%,17/190), the incidence in the probe-compressing group was significantly higher than that in the non-probe-compressing group [14.8% (12/81) vs 4.6% (5/109); χ2=5.967, P=0.015]. No statistical differences were found in rates of complications between the ECV successful and unsuccessful pregnant women, and between probe-compressing and non-probe-compressing groups (all P>0.05). No adverse maternal and neonatal outcomes related to ECV were observed. Conclusions:The ultrasonic convex array probe compressing could significantly improve the success rate of ECV in primipara without increasing the incidence of adverse maternal and fetal outcomes. The success rate of ECV in primipara is influenced by AFI and operation mode.

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.

Objective:To investigate the efficacy and safety of modified Bikini approach periacetabular osteotomy in the treatment of developmental hip dysplasia under 50 years of age.Methods:The clinical data of 39 patients with developmental hip dysplasia who underwent periacetabular osteotomy in the Department of Orthopedics, Guizhou Provincial People′s Hospital from June 2016 to June 2021 were retrospectively analyzed.Among them, 20 patients (21 hips) underwent the improved Bikini approach (study group) and 19 patients (20 hips) underwent the improved Smith-Petersen approach (control group).In the study group, there were 3 males and 17 females, aged( M(IQR))27.5 (14.3) years (range:11 to 44 years).In the control group, there were 2 males and 17 females, aged 27.5 (19.3) years (range:17 to 47 years).Both groups were sutured in the same manner by the same physician.Incision length, operation time, intraoperative blood loss and complications were recorded.X-ray images, anterior central marginal angle (ACE), lateral central marginal Angle (LCE) and acetabulum tilt angle (Tonnis AI) were measured before and after the operation.The coverage rate of acetabulum to femoral head (AHI) was measured and calculated, and the healing time was observed.Harris Hip score, International Hip score (IHOT)-12 and visual analogue scale (VAS) were recorded before and after surgery.Vancouver Scar Scale (VSS) score and patient and observer scar assessment scale (POSAS) score were recorded 12 months after surgery.The independent sample t test,Wilcoxon rank sum test, χ2 test or Fisher exact test was used to compare the clinical efficacy between the two groups, respectively. Results:All patients successfully completed the operation.There was no significant difference in operation time and intraoperative blood loss between the two groups (all P>0.05).The incision length of the study group was smaller than that of the control group, and the difference was statistically significant (10.5(5.0)cm vs.15.0(3.0), W=309.000, P=0.007).Patients were followed up for (19.1±11.1) months (range:12 to 60 months).Femoral nerve stretching injury occurred in 2 cases and sciatic branch fracture occurred in 1 case in the study group, all of which recovered to normal at 3 months follow-up, while no corresponding injury occurred in the control group.Lateral femoral cutaneous nerve injury occurred in 3 cases in the study group and 2 cases in the control group.Delayed wound healing occurred in 1 case in each of the two groups, and both healed after re-operation debridement and suture.Pubic branch nonunion occurred in 4 patients in the study group and 5 patients in the control group.There were no serious complications such as sciatic nerve and femoral blood vessel injury between the 2 groups, and there was no statistical significance in the incidence of complications between the 2 groups (52.4%(11/21) vs.40.0%(8/20), χ2=0.631, P=0.427).The clinical healing time of the patient was (4.5±1.3) months after surgery (range:3.0 to 8.0 months).There were no significant differences in ACE, LCE, Tonnis AI and AHI between the 2 groups (all P>0.05).At the last follow-up, there were no significant differences in VAS,Harris hip score and IHOT-12 score between the two groups (all P>0.05).The incision scars in the study group were smaller than those in the control group, and the differences in VSS and POSAS were statistically significant (all P<0.05). Conclusion:Compared with the improved Smith-Petersen approach, the improved Bikini approach has the same early clinical efficacy in the treatment of patients with developmental hip dysplasia under the age of 50, and has the advantages of smaller postoperative incision scars, more hidden and beautiful incision, and no serious complications, which is worthy of further study and promotion.

Objective:To investigate the efficacy and safety of modified Bikini approach periacetabular osteotomy in the treatment of developmental hip dysplasia under 50 years of age.Methods:The clinical data of 39 patients with developmental hip dysplasia who underwent periacetabular osteotomy in the Department of Orthopedics, Guizhou Provincial People′s Hospital from June 2016 to June 2021 were retrospectively analyzed.Among them, 20 patients (21 hips) underwent the improved Bikini approach (study group) and 19 patients (20 hips) underwent the improved Smith-Petersen approach (control group).In the study group, there were 3 males and 17 females, aged( M(IQR))27.5 (14.3) years (range:11 to 44 years).In the control group, there were 2 males and 17 females, aged 27.5 (19.3) years (range:17 to 47 years).Both groups were sutured in the same manner by the same physician.Incision length, operation time, intraoperative blood loss and complications were recorded.X-ray images, anterior central marginal angle (ACE), lateral central marginal Angle (LCE) and acetabulum tilt angle (Tonnis AI) were measured before and after the operation.The coverage rate of acetabulum to femoral head (AHI) was measured and calculated, and the healing time was observed.Harris Hip score, International Hip score (IHOT)-12 and visual analogue scale (VAS) were recorded before and after surgery.Vancouver Scar Scale (VSS) score and patient and observer scar assessment scale (POSAS) score were recorded 12 months after surgery.The independent sample t test,Wilcoxon rank sum test, χ2 test or Fisher exact test was used to compare the clinical efficacy between the two groups, respectively. Results:All patients successfully completed the operation.There was no significant difference in operation time and intraoperative blood loss between the two groups (all P>0.05).The incision length of the study group was smaller than that of the control group, and the difference was statistically significant (10.5(5.0)cm vs.15.0(3.0), W=309.000, P=0.007).Patients were followed up for (19.1±11.1) months (range:12 to 60 months).Femoral nerve stretching injury occurred in 2 cases and sciatic branch fracture occurred in 1 case in the study group, all of which recovered to normal at 3 months follow-up, while no corresponding injury occurred in the control group.Lateral femoral cutaneous nerve injury occurred in 3 cases in the study group and 2 cases in the control group.Delayed wound healing occurred in 1 case in each of the two groups, and both healed after re-operation debridement and suture.Pubic branch nonunion occurred in 4 patients in the study group and 5 patients in the control group.There were no serious complications such as sciatic nerve and femoral blood vessel injury between the 2 groups, and there was no statistical significance in the incidence of complications between the 2 groups (52.4%(11/21) vs.40.0%(8/20), χ2=0.631, P=0.427).The clinical healing time of the patient was (4.5±1.3) months after surgery (range:3.0 to 8.0 months).There were no significant differences in ACE, LCE, Tonnis AI and AHI between the 2 groups (all P>0.05).At the last follow-up, there were no significant differences in VAS,Harris hip score and IHOT-12 score between the two groups (all P>0.05).The incision scars in the study group were smaller than those in the control group, and the differences in VSS and POSAS were statistically significant (all P<0.05). Conclusion:Compared with the improved Smith-Petersen approach, the improved Bikini approach has the same early clinical efficacy in the treatment of patients with developmental hip dysplasia under the age of 50, and has the advantages of smaller postoperative incision scars, more hidden and beautiful incision, and no serious complications, which is worthy of further study and promotion.

Objective:To evaluate the efficacy and safety of non-submucosal injection in endoscopic submucosal excavation (ESE) for small submucosal tumors originating in the muscularis propria of the stomach.Methods:A total of 138 patients diagnosed as having small gastric muscularis propria tumors (≤2 cm) at Digestive Endoscopy Center of Zhejiang Provincial Hospital of Chinese Medical from November 2018 to October 2020 were randomly divided into the observation group with non-submucosal injection of ESE and the control group with submucosal injection of ESE for a randomized controlled trial. The exposure time, tumor removal time, operation cost, hospitalization period, numbers of metal clips and complications of the two groups were analyzed and compared.Results:A total of 138 patients were enrolled, including 76 patients in the observation group and 62 patients in the control group. All lesions were successfully and completely removed. Compared with the control group, the observation group had shorter median tumor exposure time [2.00 min VS 3.30 min, Z=-2.426, P =0.045], shorter median tumor removal time [16.8 min VS 34.4 min, Z=-4.324, P<0.001], less median surgical cost [2 903 yuan VS 3 178 yuan, Z=-5.112, P<0.001], and fewer metal clips used (4.0±0.6 VS 5.1±1.3, t=1.452, P=0.003). The incidence of postoperative abdominal distension of the observation group was lower [9.2% (7/76) VS 22.6% (14/62), χ2=2.512, P=0.049], the incidence of postoperative abdominal pain of this group was lower too [11.8% (9/76) VS 32.3% (20/62), χ2=4.242, P=0.014], but there was no significant difference in the period of hospitalization, incidence of postoperative fever or perforation ( P>0.05). Conclusion:Non-submucosal injection of ESE is safe and effective for submucosal tumors smaller than 2.0 cm originating from the muscularis propria of the stomach , which might be more advantageous than traditional ESE.