The effects of protein kinase C (PKC) inhibitors 1- (5-isoquinolinylsulfonyl) - 2-methylpoperazine (H-7) and quercetin on endotheliai-polymorphoneuclear (EC-PMN) adhesion induced by tumor necrosis factor (TNF) and platelet activating factor (PAF) were studied in cultured bovine pulmonary artery endothelial monolayers in vitro. TNF (100 U/ml) and PAF (1.0 ?mol/L) stimulated EC dependent PMN-EC adhesion. Both H-7 and quercetin dose-dependently inhibited TNF and PAF induced PMN-EC adhesion. The IC50 of H-7 was 22.22, 5.25 umol/L, and that of quercetin was 18.30, 4.83 ?mol/L respectively. WEB-2086, a specific PAF receptor antagonist, dose-dependently inhibited PAF induced PMN-EC adhesion, but had no effect on TNF induced adhesion. These results suggest that PKC play an important role in EC activation by TNF or PAF, and TNF induced PMN-EC adhesion by independent on endogenetic PAF.

Abstract: Objective　To investigate the antimicrobial activity of omadacycline (OMC) against clinical Streptococcus agalactiae (GBS) isolates, as well as its relationship with biofilm formation, resistance genes and virulence genes. Methods　A total of 136 strains of Streptococcus agalactiae isolated from Shenzhen Nanshan People's Hospital between 2015 to 2020. The minimum inhibitory concentration (MIC) of OMC against Streptococcus agalactiae was determined by broth microdilution. Crystal violet staining was used to detect the biofilm formation ability of GBS. Resistance genes (tetM, tetO, tetK, ermB, OptrA) and virulence genes (cpsⅢ, bca, fbsA, cpsA, scpB) were investigated by polymerase chain reaction (PCR). Results　Among the 136 clinical isolates of GBS, 20 strains (14.7%) were resistant to OMC, 64 (47.1%) were intermediate, and 52 (38.2%) were sensitive. Fifty-seven strains (41.9%) were biofilm-positive, 20 of which (35.1%) were sensitive to OMC. Seventy-nine strains (58.1%) were biofilm-negative, 32 of which (40.5%) were susceptible to OMC. There was a statistically significant difference in the sensitivity rates between the two groups of strains (χ2=63.062, P<0.001), but there was no significant difference in the sensitivity of OMC among the biofilm-positive strains (Fisher's exact test, P=0.824). The resistance rates of tetM, tetO, ermB and OptrA positive strains were higher than those of negative strains, while tetK was opposite. The presence of tetM (Z=0.815, P=0.415), tetO (Z=0.151, P=0.88), tetK (Z=0.567, P=0.571), ermB (Z=1.198, P=0.231) resistance genes in Streptococcus agalactiae had no significant impact on the sensitivity of OMC. However, the presence of the OptrA resistance gene showed a statistically significant effect on the sensitivity of OMC (Z=2.913, P=0.004). The virulence factors cpsⅢ, bca, fbsA, cpsA and scpB were all detected at a rate higher than 50%. The presence of the virulence genes cpsⅢ (Z=0.222, P=0.824), bca (Z=0.141, P=0.888), fbsA (Z=0.813, P=0.416), and cpsA (Z=1.615, P=0.106) in Streptococcus agalactiae had no significant impact on the sensitivity of OMC. However, there was a significant inter-group difference in the scpB virulence gene (Z=2.844, P=0.004), but the rank mean values and resistance rates of scpB-positive strains were lower than those of the negative strains. Conclusions　The formation of biofilm in Streptococcus agalactiae reduces its sensitivity to OMC, but there was no significant difference in the sensitivity to OMC among the biofilm-positive strains. The presence of resistance genes tetM, tetO, tetK, ermB, and virulence genes cpsⅢ, bca, fbsA, cpsA, scpB in Streptococcus agalactiae is not associated with OMC resistance, but the presence of the resistance gene OptrA is correlated with OMC resistance..

Objective To analyze the genomic evolution characteristics of pathogenicity islands (PAIs)in Deng strain of enteropathogenic Escherichia coli (E.coli,EPEC Deng).Methods EPEC Deng was isolated from infant stool specimen,serotypes were identified and antimicrobial susceptibility testing was performed;whole-genome se-quencing was performed by Illumina 2000 system,the locations of prophages(PPs)in the chromosome were detected using PHAST software,collinearity analysis was performed by MUMmer software,phylogenetic trees of homolo-gous gene were constructed in order to understand the evolutional rule of homology gene.PAIs prediction was per-formed using PAI finder software,the homologous evolutionary rule of PAIs core region(LEE)and core genes were clarified,genetic polymorphism was analyzed.Results The serotype of EPEC Deng strain was O119:H6,the strain was resistant to ciprofloxacin,levofloxacin,and ampicillin,but sensitive to other antimicrobial agents.The complete circular chromosome contained 5 025 482 bp with a GC content of 50.52 %,and the plasmid contained 207 564 bp with a GC content of 49.50%.A total of 17 PPs in the chromosomal genome were discovered,phyloge-netic trees analysis suggested that EPEC Deng strain was highly homologous with O26:H11 and O111 :H strains;PAIs and core genes were highly homologous with RDEC-1 and O26:H413/89-1 strains;genetic diversity analysis showed that the intimin (eae)and its receptor tir had high polymorphism,with the pi (π)value>0.10,the genes in type III secretion system was relatively stable.Conclusion The study clarified the genomic evolution characteris-tics of EPEC Deng genome and it’s PAIs,and is helpful for understanding genetic characteristics of native EPEC.

Objective To study the homology characteristics of clinicaly isolated and colonized linezolid(LZD)-resistant Enterococcus faecalis (E.faecalis) strains from a patient.Methods Ten E.faecalis strains (2 were isolated from urine specimens and 8 were from stool specimens) isolated from a patient with pulmonary infection were performed antimicrobial susceptibility testing, homology of E.faecalis was determined by pulsed-field gel electrophoresis (PFGE).Results Before and after patients received LZD therapy, 2 E.faecalis strains isolated form urine specimens were both resistant to LZD (MICs: 8 mg/mL, 16 mg/mL, respectively), among 8 strains from stool specimens (6 were isolated before therapy, and 2 were isolated after therapy), LZD susceptible, intermediate, and resistant strains were 4, 2, and 2 respectively(MICs: 0.25-12 mg/mL).10 strains of E.faecalis were homologous by PFGE typing.Conclusion In this case, the detection of E.faecalis from urinary tract and intestinal tract is homologous, which suggested that LZD-resistant Enterococcus may be colonized in vivo for a long time, and may be shift to cause bacterial infection.

Objective This study was designed to examine the clinical characteristics of bloodstream infections (BSI) caused by Staphylococcus aureus in a teaching hospital and the risk factors for 30-day mortality.Methods A single center retrospective cohort study was conducted for all the patients with BSI caused by S.aureus between 2008 and 2015.The data of clinical features,microbiology,and 30-day mortality were collected from the database of electronic medical records.Results A total of 121 patients with S.aureus BSI were identified.The prevalence of methicillin-resistant S.aureus (MRSA) was 17.4％ (21/121).MRSA BSIs were significantly associated with old age (≥65 years) (P=0.026),hospital acquired infection (P=0.035),respiratory tract infection (P=0.001),polyinfection (P=0.005) and inappropriate initial antibiotic therapy (P=0.001) than methicillin-sensitive S.aureus (MS SA) BSIs.The 30-day mortality was 18.2％ (22/121).Both univariate and multivariate analysis suggested that solid tumor (OR,8.932,P=0.004) and septic shock (OR,56.721,P＜0.001) were independently associated with the 30-day mortality.Conclusions The present study confirms that solid tumor and septic shock are more important risk factors than MRSA in mortality of patients with S.aureus BSI.

Objective To understand genetic mutation sites in linezolid (LZD)-sensitive and inducible resistant strains of methicillin-resistant Staphylococcus aureus (MRSA) using whole-genome sequencing,and realize mutation sites of LZD-resistant gene.Methods MRSA-MS4 with explicit genotype and whole-genome sequences was induced by LZD of different concentration gradients,LZD-resistant strain MRSA-MS4-LZD100 was obtained,minimum inhibitory concentration(MIC) was detected,domain V of 23S rRNA and ribosomal proteins L3/L4 gene in MRSAMS4-LZD100 were amplified by polymerase chain reaction (PCR),the sequenced products obtained the corresponding mutation site in contrast with the wild-type strain;Illumina PE library was constructed through paired-end sequencing by Illumina HiSeq 2000 technique,and whole genome sequencing was completed based on bioinformatics.Results MRAS-MS4-LZD100 strain was induced after 32 passages,MIC of LZD was 96 μg/mL.Sequencing of PCR products indicated the genetic variations were G2447T mutation in multiple copies of domain V of 23S rRNA gene,and Gly113Val mutation in L3 protein respectively;the whole genome of MRSA-MS4-LZD100 contained 2 744 315 bp,annotation of the whole genome found a total of 2 509 genes,11 tRNA-encoding genes and 2 entire rRNA-encoding operons.The data were submitted to the PubMed,and the GeneBank accession number JXMJ00000000 was assigned;a total of 101 SNPs and 6 Small indels were found,16 of 101SNP mutations occurred in exon,of which the variant proteins with anmino acid sequence alterations included IstB ATP binding domain-containing protein,clumping factor A,IS1272 transposase and so on;3 of 6 Small indel mutations occurred in exon,of which the variant proteins with anmino acid sequence alterations included hypothetical protein,30S ribosomal protein S1,and clumping factor A.Conclusion LZD-resistant strain MRSA-MS4-LZD100 was successfully induced by LZD;beside 23S rRNA V domain and ribosomal L3 protein,the other mutant site exist in this resistant strain,which provide some direction for subsequent study of recessive LZD resistance mechanism.

Background::Due to the wide variety of morphology, size, and dynamics, selecting an optimal valve size and location poses great difficulty in percutaneous pulmonary valve implantation (PPVI). This study aimed to report our experience with in vitro bench testing using patient-specific three-dimensional (3D)-printed models for planning PPVI with the Venus P-valve. Methods::Patient-specific 3D soft models were generated using PolyJet printing with a compliant synthetic material in 15 patients scheduled to undergo PPVI between July 2018 and July 2020 in Central China Fuwai Hospital of Zhengzhou University.Results::3D model bench testing altered treatment strategy in all patients (100%). One patient was referred for surgery because testing revealed that even the largest Venus P-valve would not anchor properly. In the remaining 14 patients, valve size and/or implantation location was altered to avoid valve migration and/or compression coronary artery. In four patients, it was decided to change the point anchoring because of inverted cone-shaped right ventricular outflow tract (RVOT) ( n = 2) or risk of compression coronary artery ( n = 2). Concerning sizing, we found that an oversize of 2-5 mm suffices. Anchoring of the valve was dictated by the flaring of the in- and outflow portion in the pulmonary artery. PPVI was successful in all 14 patients (absence of valve migration, no coronary compression, and none-to-mild residual pulmonary regurgitation [PR]). The diameter of the Venus P-valve in the 3D simulation group was significantly smaller than that of the conventional planning group (36 [2] vs. 32 [4], Z = -3.77, P <0.001). Conclusions::In vitro testing indicated no need to oversize the Venus P-valve to the degree recommended by the balloon-sizing technique, as 2-5 mm sufficed.

Objective: To determine the value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) on predicting the long-term outcome of patients with hypertrophic cardiomyopathy (HCM) . Methods: NT-proBNP was measured in 831 consecutive patients with HCM at Fuwai Hospital from October 2009 to December 2013 and patients were followed up clinically for (53.3±15.4) months. Patients were divided into 3 groups according to NT-proBNP values: NT-proBNP<860 pmol/L (n=276) , 860 pmol/L≤NT-proBNP≤1 905 pmol/L (n=278) , NT-proBNP>1 905 pmol/L (n=277) . The related baseline data, laboratory examination and echocardiographic results were compared among groups. The primary endpoints of this study were all-cause mortality and cardiac transplantation. Cox proportional hazards model was used to estimate hazard ratio (HR) . Kaplan-Meier analysis was used to evaluate the survival status of patients among the 3 groups. Results: During a median follow-up of (53.3±15.4) months, all-cause mortality or cardiac transplantation occurred in 37 patients (4.5%) , event rate was 1.4% (4/276) , 4.0% (11/278) and 7.9% (22/277) in patients with NT-proBNP<860 pmol/L, 860 pmol/L≤NT-proBNP≤1 905 pmol/L and NT-proBNP>1 905 pmol/L, respectively. Multivariable Cox regression analysis identified that age (HR 1.066, 95%CI 1.027-1.107) and NT-proBNP (HR 1.026, 95% CI 1.010-1.042) were independent predictors of all-cause mortality or cardiac transplantation. Among the 3 groups, the survival rate of the NT-proBNP<860 pmol/L group was the highest,and that of the NT-proBNP>1 905 pmol/L group was the lowest (P<0.01) . Conclusions The level of NT-proBNP provides clinically relevant information for long-term adverse events risk stratification in patients with HCM.

Objective: This cross-sectional study aimed to address the relationship between the volume of epicardial adipose tissue (EAT) with cardiovascular risk factors and coronary artery calcification(CAC) in the community residents. Methods: Individuals were recruited from the Jidong Community (Tangshan City, Northern China) which mainly comprised employees of the Jidong Co. Ltd. and their family members. From July 2013 to August 2014, 2 647 participants aged ≥40 years were included in this study. The volume of EAT and coronary artery calcification score (CAC score) were determined by a 64-slice CT. Carotid intima-media thickness (CIMT) was measured by a trained sonographer using a high-resolution B-mode topographic ultrasound system. Venous blood samples were analyzed by automated analyzers in the central laboratory. A validated questionnaire specifically designed for this study was used to collect demographic data from all participants by trained doctors. Characteristics of study cohort were compared according to quartiles of EAT volume (n=660, 663, 662, 662, repectively). Results: (1) The mean age of participants was (55.31±7.76) years and 49.94% (n=1 322) were men. The median EAT volume (interquartile) was 129.42 (95.66, 176.51)cm³. (2) Age, BMI, waist circumference and hip circumference, systolic blood pressure, LDL-C, triglycerides, and fasting blood glucose were significantly higher, while HDL-C level was significantly lower in participants with higher EAT volume than participants with lower EAT volume (all P<0.05). Carotid intima-media thicken (CIMT) and higher CAC score were also significantly higher in participants with higher volume of EAT. Furthermore, percentage of diabetes mellitus, hypertension, hyperlipidemia increased in proportion with increasing EAT volume (P<0.05). (3) In the linear regression, significant positive relations were found for age (β=0.019 3, 95%CI 0.017-0.021, P<0.001), waist circumference (β=0.012 7, 95%CI 0.009-0.016, P<0.001), BMI (β=0.022 4, 95%CI 0.013-0.032, P<0.001), LDL-C (β=0.048 4, 95%CI 0.021-0.076, P<0.001), and HDL-C (β=-0.098 1, 95%CI-0.164--0.032, P<0.001) was inversely related to the EAT volume. (4) Logistic regression analysis indicated that EAT volume was an independent risk factor for CAC score>0 (OR=1.233, 95%CI 1.205-1.262, P<0.001) . Conclusions Our findings indicate that EAT volume is strongly correlated to cardiovascular risk factors and coronary calcification and is an independent risk factor of increased coronary calcification in community residents.

Objective:To evaluate the medium-term clinical and hemodynamic outcomes of percutaneous pulmonary valve implantation (PPVI) using a domestic Venus-P self-expanding valve in the treatment of severe pulmonary regurgitation after Tetralogy of Fallot (TOF).Methods:Retrospective study.From December 2017 to December 2020, 13 TOF patients with (17.8±4.7) years old and (50.2±12.3) kg underwent PPVI using the Venus-P self-expanding valve in the Department of Children′s Heart Center, Zhengzhou University People′s Hospital were recruited.The mean valve size was (31.9±3.1) mm.All patients received the transannular patch surgery and developed severe pulmonary regurgitation.After PPVI, 13 patients were followed up for at least 12 months.The operation-related complications, improvement of valve and heart function and the durability and reintervention of the Venus-P self-expanding valve were analyzed.The right ventricular end-diastolic volume index (RVEDVi) before and after operation was compared by the paired t-test, and the New York Heart Association (NYHA) class was compared by the paired Wilcoxon signed rank sum test. Results:PPVI was successfully performed in all 13 patients without death.At 6 months post-PPVI, cardiac magnetic resonance imaging findings showed that RVEDVi was significantly reduced[(145.7±9.6) mL/m 2vs.(100.2±12.2) mL/m 2, P<0.05], and the NYHA class was significantly improved ( P<0.05). One patient presented moderate pulmonary valve regurgitation at 12 months postoperatively.No vegetation was found on echocardiography, and blood culture was negative in this case.Six patients did not have postoperative pulmonary valve regurgitation, and the remaining presented mild or less pulmonary regurgitation.One patient had sudden ventricular tachycardia on the 6 th day postoperatively, which was converted to sinus rhythm after synchronous electrocardiography.Only one case underwent appendectomy 7 months after operation due to acute appendicitis, and the remaining did not require valve-related reintervention after implantation.During the follow-up for (22.8±8.0) months, no patients had perivalve leakage, stent migration and rupture.Complications like embolization and coronary artery compression were not reported. Conclusions:PPVI using the Venus-P self-expanding valve is safe and effective in patients with severe pulmonary valve regurgitation after TOF surgery, showing an acceptable medium-term follow-up outcome.Studies with a large sample size and long follow-up period are still needed to validate our findings.