The growth of three plague phages from Qinghai Plateau in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,PTB5,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were detected through a micromethod based on the OmniLogTM microbial identification system and by the drop method,to provide a scientific basis for future ecological studies and classification based on the host range.For plague vaccine strains EV76 and 614F,successful phage infection and subsequent phage growth were observed in the host bacte-rium.Diminished bacterial growth and respiration and a concomitant decrease in color were observed with the OmniLogTM mi-crobial identification system at 33 ℃ for 48 h.Yersinia pseudotuberculosis PTB5 was sensitive to Yersinia pestis phage 476,but Yersinia pseudotuberculosis PST5 was insensitive to phage 087 and 072204.Three strains of non-Yersinia pestis(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were insensitive to Yersinia pestis pha-ges 087,072204,and 476 showed similar growth curves.The growth of phages 476 and 087,as determined with the drop method,in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersin-ia enterocolitica 52302-2)showed the same results at 37 ℃,on the basis of comparisons with the OmniLogTM microbial i-dentification system;in contrast,phages 072204 did not show plaques on solid medium at 37 ℃ with plague vaccine strains EV76 and 614F.Determination based on the OmniLogTM detection system can be used as an alternative to the traditional determination of the host range,thus providing favorable application val-ue for determining the interaction between the phage and host bacteria.

Objective To investigate the effects of astragaloside Ⅳ(AS-Ⅳ)on axon growth inhibitory factor A(Nogo-A)and its downstream pathway protein RHO-associated coiled spiral kinase 2(ROCK2)in experimental autoimmune encephalomyelitis(EAE)mice,and to explore the mechanism by which it promotes axon repair and regeneration.Methods EAE model was induced in C57BL/6 female mice by subcutaneous injection of myelin oligodendrocyte glycoprotein 35-55(MOG35-55).Mice were randomly divided into EAE group and AS-Ⅳ group(n=8 per group).EAE group received intraperitoneal injection of PBS on the 3rd day post-immunization,while AS-Ⅳ group was administered AS-Ⅳ at a dosage of 30mg/(kg.d)once daily,0.2 ml per injection,for 25 consecutive days.On the 28th day post-immunization,the expression levels of growth-associated protein 43(GAP-43),neuronal core antigen(NeuN),microtubule associated protein 2(MAP-2),glial fibroacidic protein(GFAP),and Iba1 in the spinal cord were detected using immunofluorescence assay.Real-time fluorescence quantitative PCR(qRT-PCR)was conducted to detect mRNA expression levels of GAP-43,Nogo-A,and Nogo receptor(NgR)genes.Western blotting was utilized to determine the expression levels of GAP-43,Nogo-A,ROCK2,phosphorylated myosin phosphatase(p-MYPT1),B-lymphoblastoma-2(Bcl-2),and Bcl-2 associated X protein(Bax).Results Compared with EAE group,AS-Ⅳ treatment significantly reduced the positive cell expression rates of Iba1 microglia and GFAP astrocyte in spinal cord(P<0.01 and P<0.001,respectively),while it also increased the positive expression rates of NeuN and MAP-2(P<0.001 and P<0.05,respectively).The treatment also upregulated the expression level of anti-apoptotic factor Bcl-2(P<0.001)and downregulated the expression level of pro-apoptotic factor Bax(P<0.05),leading to an increase in Bcl-2/Bax ratio(P<0.05).Furthermore,AS-Ⅳ enhanced the expression of GAP-43 protein(P<0.05)and decreased the mRNA expression levels of neuroregeneration inhibitor Nogo receptor(NgR)and ROCK2 gene(P<0.001,P<0.05,respectively);as well as decreased the expression levels of Nogo-A,ROCK2 and p-MYPT1 proteins(P<0.05,P<0.001).Conclusion AS-Ⅳ may inhibit the activation of microglia and astrocytes and neuronal apoptosis in EAE mice by inhibiting Nogo-A and downstream pathway ROCK 2,thereby promoting the expression of GAP-43,NeuN and MAP-2,alleviating neuronal damage,and facilitating axon repair and regeneration.

Objective To measure the distance between the lateral compression Ⅱ(LC-Ⅱ)screw guide needle and the surrounding important structures around the anterior inferior iliac spine in pelvic fractures and to locate the needle point,so as to provide anatomical reference for clinical nail placement.Methods Totally 40 adult gross specimens of embalming were implanted with LC-Ⅱ screw guide needle under the surveillance of C-arm machine,and the specimens were dissected.The shortest distance between the insertion point and the lateral femoral cutaneous nerve,femoral nerve,femoral artery,femoral vein,anterior superior iliac spine and inguinal ligament was measured.The triangle was constructed between the insertion point,anterior superior iliac spine and inguinal ligament,and the exact location of the entry point was calculated.Results The average distance between the insertion point of the male needle and the femoral vein was(50.67±7.29)mm＞the anterior superior iliac spine(43.83±7.58)mm＞the femoral artery(38.35±6.63)mm＞the femoral nerve(31.17±1.67)mm=the inguinal ligament(28.69±6.59)mm＞the lateral femoral cutaneous nerve(7.98±3.81)mm.The mean distance between the insertion point of the female needle and the anterior superior iliac spine was(45.28±7.07)mm=femoral vein(43.72±6.89)mm＞femoral artery(33.76±6.33)mm＞femoral nerve(25.66±6.46)mm=inguinal ligament(23.22±5.00)mm＞lateral femoral cutaneous nerve(8.97±4.76)mm.The projection distance of the entry point was 31.77 mm for men and 38.41 mm for women.The Angle b was 42.81°for men and 31.71° for women.Conclusion The lateral femoral cutaneous nerve is most vulnerable to injury when LC-Ⅱ screw is inserted,and the risk of injury has nothing to do with sex.The insertion point positioning method a and b made LC-Ⅱ screw placement quickly,safely and accurately,and reduced fluoroscopy time and frequency.

Objective: To explore the balance of peripheral blood T helper 17 cells/regulatory T cell (Th17/Treg) ratio and the polarization ratio of M1 and M2 macrophages in lower extremity arteriosclerosis obliterans (ASO). Methods: A rat model of lower extremity ASO was established, and blood samples from patients with lower extremity ASO before and after surgery were obtained. ELISA was used to detect interleukin 6 (IL-6), IL-10, and IL-17. Real-time RCR and Western blot analyses were used to detect Foxp3, IL-6, IL-10, and IL-17 expression. Moreover, flow cytometry was applied to detect the Th17/Treg ratio and M1/M2 ratio. Results: Compared with the control group, the iliac artery wall of ASO rats showed significant hyperplasia, and the concentrations of cholesterol and triglyceride were significantly increased (P<0.01), indicating the successful establishment of ASO. Moreover, the levels of IL-6 and IL-17 in ASO rats were pronouncedly increased (P<0.05), while the IL-10 level was significantly decreased (P<0.05). In addition to increased IL-6 and IL-17 levels, the mRNA and protein levels of Foxp3 and IL-10 in ASO rats were significantly decreased compared with the control group. The Th17/Treg and M1/M2 ratios in the ASO group were markedly increased (P<0.05). These alternations were also observed in ASO patients. After endovascular surgery (such as percutaneous transluminal angioplasty and arterial stenting), all these changes were significantly improved (P<0.05). Conclusions: The Th17/Treg and M1/M2 ratios were significantly increased in ASO, and surgery can effectively improve the balance of Th17/Treg, and reduce the ratio of M1/M2, and the expression of inflammatory factors.

Objective To investigate the prevalence of zika virus(ZIKV),dengue virus(DENV)and chikungunya virus(CHIKV)infections in blood donors in Kunming,China.Methods A total of 10 662 samples from blood donors in Kunming from August 2022 to October 2023 were randomly collected,and ZIKV RNA,DENV RNA and CHIKV RNA were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction(RT-qPCR).Results Effec-tive test results were obtained from 10 554 samples,and no positive case of ZIKV RNA,DENV RNA and CHIKV RNA was found in this investigation.Conclusion The risk of ZIKV,DENV and CHIKV infections among blood donors in Kunming is low,and there is no immediate need for routine screening for these viruses among blood donors in this region.

Objective To investigate the Gram-positive coccus resistance in nationwide's tertiary hospitals and understand the trend of antimicrobial resistance.Methods All the clinical isolates were collected from 19 hospitals and the minimal inhibitory concentrations(MICs)were tested using agar/broth dilution method recommended.Results A total of 1 974 pathogenic Gram-positive coccus from 19 tertiary hospitals in 19 cities nationwide over the period from July 2021 to June 2022 were studied.Based on the MIC results,the prevalence of methicillin resistant Stapylococcus aureus(MRSA)and methicillin resistant Stapylococcus epidermidis(MRSE)were 36.4％and 79.9％respectively.No vancomycin insensitivity Staphylococcus was detected.Staphylococcus aureus were 100％susceptibility to linezolid and teicoplanin.Antibiotic resistance rate of Enterococcus faecalis and Enterococcus faecium to ampicillin were 3.1％and 92.9％.The detectation rate of vancomycin resistant Enterococcus(VRE)was 1.6％.Nonsusceptibility rate of Enterococcus faecalis to linezolid was 32.2％,two consecutive monitoring rises and nonsusceptibility rate of Enterococcus faecium(12.5％)was also significantly increased.The prevalence of penicillin non-susceptible Streptococcus pneumoniae(PNSSP)was 0.8％based on non-meningitis and parenteral administration criterion,decrease of nearly 30 percentage points from the previous surveillance.While for cases of oral penicillin,the rate was 71.8％,showing similar to last time.The results indicated that the number of strains with higher MIC value of penicillin(MIC ≥4 mg·L-1)decreased significantly.There were no significant differences of resistance rates of Stapylococcus aureus,Stapylococcus epidermidis,Enterococcus faecalis,Enterococcus faecium and Streptococcus pneumoniae among various groups such as different department,age,or specimen source.Conclusion VRE detection ratio stablized at a relatively low level.The number of Streptococcus pneumoniae with higher MIC value of penicillin decreased significantly compared with the previous monitoring.The increase of linezolidin-insensitive Enterococcus was noteworthy.

Objective To investigate the Gram-negative bacteria resistance in nationwide's tertiary hospitals and understand the trend of antimicrobial resistance.Method All the clinical isolates were collected from 19 hospitals and the minimal inhibitory concentrations(MICs)were tested using agar/broth dilution method recommended.Results A total of 4 066 pathogenic isolates from 19 tertiary hospitals in 19 cities nationwide over the period from July 2021 to June 2022 were studied.Based on the MIC results,Escherichia coli and Klebsiella pneumoniae showed extended spectrum β-lactamase(ESBLs)phenotype rates of 55.0％and 21.0％,respectively,ESBLs phenotype rate of Klebsiella pneumoniae keep going down.The ratios of carbapenems resistance Klebsiella pneumoniae increased by 5 percentage points compared with the previous monitoring.Carbapenems,moxalactam,sitafloxacin,β-lactam combination agents,fosfomycin trometamol,and amikacin displayed desirable antibacterial activity against Enterbacterales,susceptibal rates were above 75％.In addition,tigacycline,omacycline,colistin and fluoxefin maintained good antibacterial activity against their respective effective bacteria/species,and the bacterial sensitivity rates by more than 80％.Resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannnii to imipenem were 26.3％and 72.1％and multidrug-resistant(MDR)detection rates were 41.1％and 77.3％,extensively drug-resistant(XDR)were 12.0％and 71.8％,respectively.Comparison of drug resistance rates from different wards,ages and specimen sources indicated that the proportion of resistance in Klebsiella pneumoniae and Acinetobacter baumannii isolated from intensive care unit(ICU)were significantly higher than non-ICU.Carbapenem resistance rates of Klebsiella pneumoniae isolated from ICU were more than 35％.Resistance rates of Haemophilus influenzae isolated in children to β-lactam,macrolide,clindamycin and ESBLs detection rate in Klebsiella pneumoniae isolated from children were more than those from adults and the old people,so bacterial resistance in children is an important problem in China.Conclusion ESBLs detection rate of Escherichia coli increased slightly after years of continuous decline.The proportion of carbapenem resistant Pseudomonas aeruginosa was stable,but the resistance rate of Klebsiella pneumoniae and Acinetobacter baumannii to carbapenems was still increased,which should be paid more attention.

Objective::Many studies have shown that blood glucose fluctuations (GFs) are more harmful to patients with diabetes mellitus (DM) than sustained hyperglycemia. However, the effect of GF on electrocardiogram (ECG) parameters and vulnerability to ventricular tachycardia/fibrillation (VT/VF) remains poorly characterized. This study aimed to assess the effect of GF on ECG parameters and induction of VT/VF in streptozotocin (STZ)-induced diabetic Sprague-Dawley rats.Methods::Male Sprague-Dawley rats were injected with STZ and randomly divided into 3 treatment groups: controlled STZ-induced diabetic rats (C-STZ) ( n = 10); uncontrolled STZ-induced diabetic rats (U-STZ) ( n = 10); and STZ-induced diabetic rats with glucose fluctuations (GF-STZ) ( n = 10). After 12 weeks, baseline ECG recordings were taken and a VT/VF test was performed with the administration of caffeine and dobutamine. Hematoxylin & eosin and masson staining were used to evaluate pathological cardiac changes after intervention. Results::No significant difference in heart rate, RR interval, P wave (duration and height), PR segment, PR interval, QRS wave duration, and T wave height was observed among the 3 groups ( P > 0.05). Compared with the C-STZ group, the U-STZ and GF-STZ groups both had a longer T wave duration ((62.41 ± 2.38) ms vs. (78.37 ± 4.64) ms and (96.06 ± 4.60) ms, P < 0.05), QT interval ((83.66 ± 2.31) ms vs. (101.75 ± 4.56) ms and (119.14 ± 4.88) ms, P < 0.05), and QTc interval ((77.45 ± 1.36) ms vs. (91.36 ± 3.49) ms and (104.55 ± 3.01) ms, P < 0.05), all of which were longest in the GF-STZ group ( P < 0.05). Additionally, the GF-STZ group had the highest VT/VF occurrence and duration and the highest arrhythmia score. Conclusion::This study revealed GF can significantly prolong the QT interval, QTc interval, and T wave duration, as well as increase vulnerability to VT/VF in rats, which may be an important electrophysiological mechanism of GF-related ventricular arrhythmia.

Objective::Many studies have shown that blood glucose fluctuations (GFs) are more harmful to patients with diabetes mellitus (DM) than sustained hyperglycemia. However, the effect of GF on electrocardiogram (ECG) parameters and vulnerability to ventricular tachycardia/fibrillation (VT/VF) remains poorly characterized. This study aimed to assess the effect of GF on ECG parameters and induction of VT/VF in streptozotocin (STZ)-induced diabetic Sprague-Dawley rats.Methods::Male Sprague-Dawley rats were injected with STZ and randomly divided into 3 treatment groups: controlled STZ-induced diabetic rats (C-STZ) ( n = 10); uncontrolled STZ-induced diabetic rats (U-STZ) ( n = 10); and STZ-induced diabetic rats with glucose fluctuations (GF-STZ) ( n = 10). After 12 weeks, baseline ECG recordings were taken and a VT/VF test was performed with the administration of caffeine and dobutamine. Hematoxylin & eosin and masson staining were used to evaluate pathological cardiac changes after intervention. Results::No significant difference in heart rate, RR interval, P wave (duration and height), PR segment, PR interval, QRS wave duration, and T wave height was observed among the 3 groups ( P > 0.05). Compared with the C-STZ group, the U-STZ and GF-STZ groups both had a longer T wave duration ((62.41 ± 2.38) ms vs. (78.37 ± 4.64) ms and (96.06 ± 4.60) ms, P < 0.05), QT interval ((83.66 ± 2.31) ms vs. (101.75 ± 4.56) ms and (119.14 ± 4.88) ms, P < 0.05), and QTc interval ((77.45 ± 1.36) ms vs. (91.36 ± 3.49) ms and (104.55 ± 3.01) ms, P < 0.05), all of which were longest in the GF-STZ group ( P < 0.05). Additionally, the GF-STZ group had the highest VT/VF occurrence and duration and the highest arrhythmia score. Conclusion::This study revealed GF can significantly prolong the QT interval, QTc interval, and T wave duration, as well as increase vulnerability to VT/VF in rats, which may be an important electrophysiological mechanism of GF-related ventricular arrhythmia.

Objective: To evaluate the effect of Li's catheter in cardiac resynchronization therapy (CRT) implantation. Methods: This study was a retrospective cohort study. Patients with indications for CRT implantation who visited the Department of Cardiology, Peking University People's Hospital from January 1, 2016 to January 1, 2022 were enrolled. Patients were divided into Li's catheter group (CRT implantation with Li's catheter) and control group (CRT implantation with the traditional method). The general clinical data of the patients were obtained through the electronic medical record system. Li's catheter is a new type of coronary sinus angiography balloon catheter independently developed by Dr. Li Xuebin (patent number: 201320413174.1). The primary outcome was the success rate of CRT device implantation, and the secondary outcomes included efficacy and safety parameters. Efficacy indicators included operation time, coronary sinus angiography time, left ventricular lead implantation time, X-ray exposure time, left ventricular lead threshold, and diaphragm stimulation. Safety outcomes included incidence of coronary sinus dissection, cardiac tamponade, and pericardial effusion. Results: A total of 170 patients were enrolled in this study, including 90 in Li's catheter group and 80 in control group. Age, male proportion of patients, proportion of patients with ischemic cardiomyopathy, hypertension, diabetes mellitus, chronic renal insufficiency, New York Heart Association (NYHA) functional classification, left ventricular ejection fraction, left ventricular end-diastolic diameter, proportion of left bundle branch block, and preoperative QRS wave width were similar between the two groups (all P>0.05). In Li's catheter group, 34 cases (37.8%) implanted with CRT defibrillators, and 28 cases (35.0%) implanted with CRT defibrillators in control group, the difference was not statistically significant (P=0.710). The success rate of CRT device implantation in Li's catheter group was 100% (90/90), which was significantly higher than that in control group (93.8%, 75/80, P=0.023).The operation time was 57.0 (52.0, 62.3) minutes, the time to complete coronary sinus angiography was 8.0 (6.0, 9.0) minutes, and the time of left ventricular electrode implantation was 8.0 (7.0, 9.0) minutes in Li's catheter group, and was 91.3 (86.3, 97.0), 18.0 (16.0, 20.0), 25.0 (22.0, 27.7) minutes respectively in control group, all significantly shorter in Li's catheter group (all P<0.05). The exposure time of X-ray was 15.0 (14.0, 17.0) minutes in Li's catheter group, which was also significantly shorter than that in control group (32.5 (29.0, 36.0) minutes, P<0.001). There was no coronary sinus dissection and cardiac tamponade in Li's catheter group, and 1 patient (1.1%) had diaphragmatic stimulation in Li's catheter group. In control group, 6 patients (6.7%) had coronary sinus dissection, and 1 patient (1.1%) developed pericardial effusion, and 3 patients (3.3%) had diaphragmatic stimulation. The incidence of coronary sinus dissection in Li's catheter group was significantly lower than that in control group (P=0.011). The postoperative left ventricular thresholds in Li's catheter group and control group were similar (1.80 (1.60, 2.38) V/0.5 ms vs. 1.80 (1.60, 2.40) V/0.5 ms, P=0.120). Conclusions: Use of Li's catheter is associated with higher success rate of CRT implantation, short time of coronary sinus angiography and left ventricular electrode implantation, reduction of intraoperative X-ray exposure, and lower incidence of coronary vein dissection in this patient cohort.
Cardiac Resynchronization Therapy/methods* ; Cardiac Tamponade/therapy* ; Catheters ; Heart Failure/therapy* ; Humans ; Male ; Pericardial Effusion ; Retrospective Studies ; Stroke Volume ; Treatment Outcome ; Ventricular Function, Left