To understand the pathogenicity,virulence genes,drug resistance genes,and drug resistance of Staphylococcus aureus isolated from yaks in some areas of Lhasa and Nagqu City,55 yak nasal swab samples were analyzed for S.aureus in this study.The cocci were isolated and identified,and the carriage of virulence genes and drug resistance genes,as well as the pathogenicity and drug sensitivity of the isolated S.aureus strains,were detected with PCR,artificially infected mice,and the K-B drug susceptibility disk method.Seven strains of S.aureus were isolated from the 55 yak nasal swab samples,with an iso-lation rate of 12.73％.The isolated strains were all pathogenic to mice,with a fatality rate exceeding 60％.These seven strains of S.aureus carried three drug resistance genes(tetM,tet,and mecA)and six virulence genes(seb,sec,clfA,hla,hlb,and nuc).The detection rate of the three drug resistance genes was 100％,whereas the detection rate of the six virulence genes in the isolates ranged from 83.33％to 100％.The resistance rates of the isolated strains to penicillin,ampicillin,and cotrimox-azole reached 85.71％-100％,whereas the resistance rates to tetracycline and ceftazidime were both 28.57％.Thus,yaks in Lhasa and Nagqu cities were found to be infected by S.aureus strains carrying various drug-resistance genes and virulence genes.These strains were highly pathogenic and showed sensi-tivity to most antibacterial drugs.These findings may serve as a reference for treating S.aureus infection in yaks in the cities of Lhasa and Nagqu.

Objective:To optimize the technical parameters related to the preparation of novel frozen human platelets and formulate corresponding protocol for its preparation.Methods:Novel frozen human platelets were prepared with O-type bagged platelet-rich plasma(PRP),the key technical parameters(DMSO addition,incubation time,centrifugation conditions,etc.)of the preparation process were optimized,and the quality of the frozen platelets was evaluated by routine blood tests,apoptosis rate,platelet activation rate and surface protein expression level.Results:In the preparation protocol of novel frozen human platelets,the operation of centrifugation to remove supernatant was adjusted to before the procedure of platelets freezing,and the effect of centrifugation on platelets was minimal when the centrifugation condition was 800 xg for 8 min.In addition,platelets incubated with DMSO for 30 min before centrifugation exhibited better quality after freezing and thawing.The indexes of novel frozen human platelets prepared with this protocol remained stable after long-term cryopreservation.Conclusion:The preparation technique of novel frozen human platelets was established and the protocol was formulated.It was also confirmed that the quality of frozen platelets could be improved by incubating platelets with DMSO for 30 min and then centrifuging them at 800 ×g for 8 min in the preparation of novel frozen human platelets.

Tissue regeneration is an important engineering method for the treatment of oral soft and hard tissue defects.Growth factors,as one of the three elements of tissue regeneration,are a necessary condition for tissue regeneration.Concentrated growth factor(CGF)is a new generation of blood extract prepared by changing the centrifugal speed on the basis of the preparation of platelet-rich plasma(PRP)and platelet-rich fibrin(PRF).It contains abundant growth factors and a fibrin matrix with a three-dimensional network structure,being capable of activating angiogenesis and promoting tissue regeneration and healing.CGF has been widely used in the repair and regeneration of oral soft and hard tissues.This paper introduces the preparation and composition of CGF and reviews the application of CGF in oral implantation and the regeneration of oral bone tissue,periodontal tissue,and dental pulp tissue.
Platelet-Rich Plasma/metabolism* ; Platelet-Rich Fibrin ; Cell Proliferation ; Bone and Bones ; Intercellular Signaling Peptides and Proteins/metabolism* ; Bone Regeneration

Objective: To investigate the predictive value of glycosylated hemoglobin A1c/apolipoprotein A-1 (HbA1c/ApoA-1) ratio for major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS). Methods: The present study is a retrospective cohort study. ACS patients who were hospitalized and underwent coronary angiography at Beijing Hospital from March 2017 to March 2019 were enrolled. Baseline information such as sex, age, previous history, Gensini score, HbA1c and ApoA-1 were analyzed. Patients were divided into two groups according to presence or absence of MACEs and the difference on HbA1c/ApoA-1 ratio was compared between the two groups. According to the tertiles of HbA1c/ApoA-1 levels, patients were divided into high (5.87-16.12), medium (4.50-5.83) and low (2.11-4.48) HbA1c/ApoA-1 groups. Cox proportional risk model was used to evaluate the differences in MACEs and all-cause mortality among the three groups. Kaplan-Meier survival analysis was used to compare the differences of MACEs between the various HbA1c/ApoA-1 groups. Results: A total of 366 ACS patients were included in this study. The mean age of the patients was (65.9±10.3) years. There were 59 MACEs and 10 all-cause deaths during the mean of (22.3±4.4) months follow-up. After adjusting for age, systolic blood pressure, history of diabetes and Gensini score, the incidence of MACEs was 2.45 times higher in the high HbA1c/ApoA-1 group than in the low HbA1c/ApoA-1 group (95%CI 1.16-5.18, P=0.019). There was no significant difference in all-cause mortality between the high and low HbA1c/ApoA-1 groups (P=1.000). Kaplan-Meier survival analysis showed that patients in the high HbA1c/ApoA-1 group had the highest risk of MACEs, while patients in the low HbA1c/ApoA-1 group had the lowest risk of MACEs (P<0.01). Spearman rank correlation analysis showed that HbA1/ApoA-1 ratio was positively correlated with Gensini score in ACS patients (r=0.274, P<0.01). Conclusion: High HbA1c/ApoA-1 ratio was an independent risk factor for MACEs in ACS patients. Patients with high HbA1c/ApoA-1 ratio had more severe coronary artery disease lesions. HbA1c/ApoA-1 ratio may be used as a potential risk stratification biomarker for ACS patients, it might be useful for the early identification of high-risk population and for predicting the incidence of MACEs among ACS patients.
Aged ; Humans ; Middle Aged ; Acute Coronary Syndrome/diagnosis* ; Apolipoprotein A-I/analysis* ; Biomarkers/analysis* ; Glycated Hemoglobin/analysis* ; Percutaneous Coronary Intervention ; Retrospective Studies ; Risk Factors ; Predictive Value of Tests

Objective To investigate the distribution and drug resistance of pathogenic bacteria for infection after liver transplantation, and to provide a scientific basis for the rational clinical application of antibiotics. Methods The pathogenic bacteria isolated from the specimens of 904 patients with infection after liver transplantation in The Affiliated Hospital of Qingdao University from March 2014 to December 2021 were analyzed in terms of distribution and drug resistance. WHONET 5.6 software was used to perform a statistical analysis of strains and bacterial resistance rate, and Excel was used to analyze the sources of specimens, composition ratios, and distribution of pathogenic bacteria. Results A total of 2 208 non-repetitive pathogenic bacteria were isolated, mainly from the specimens of respiratory tract (31.25%), bile (22.28%), ascites (13.18%), blood (8.38%), and drainage fluid (4.62%). The top 10 pathogenic bacteria were Klebsiella pneumoniae subspecies (10.69%), Enterococcus faecium (10.42%), Escherichia coli (8.24%), Pseudomonas aeruginosa (8.24%), Staphylococcus epidermidis (8.06%), Acinetobacter baumannii (7.93%), Stenotrophomonas maltophilia (6.61%), Enterobacter cloacae (3.22%), Staphylococcus haemolyticus (3.08%), and Staphylococcus aureus (2.94%), accounting for 69.43% of the total pathogenic bacteria. Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Klebsiella pneumoniae subspecies, and Acinetobacter baumannii were the main pathogenic bacteria isolated from respiratory tract specimens; Enterococcus faecium was the main pathogenic bacterium isolated from bile, ascites, and drainage fluid specimens; Escherichia coli , Staphylococcus epidermidis , and Klebsiella pneumoniae subspecies were the main pathogenic bacteria isolated from blood specimens. Drug sensitivity data showed that Enterobacterales bacteria had a relatively high resistance rate to cephalosporins and fluoroquinolones and a resistance rate of < 10% to amikacin among aminoglycosides, with no strains resistant to tigecycline; compared with Escherichia coli , Klebsiella pneumoniae subspecies had a higher resistance rate to meropenem (14.71% vs 5.66%) and imipenem (11.35% vs 6.29%); non-fermentative bacteria had a relatively high resistance rate to carbapenems, with a resistance rate of < 10% to tigecycline and colistin. Among Gram-positive cocci, Enterococcus faecium had a resistance rate of 6.17% to vancomycin and 2.44% to quinupristin/dalfopristin, with no strains resistant to tigecycline and linezolid; Staphylococcus epidermidis had a resistance rate of > 50% to macrolides, fluoroquinolones, sulfonamides, and lincomycin, and a small part of these strains were resistant to linezolid and quinupristin/dalfopristin (< 3%), with no Staphylococcus epidermidis strains resistant to tigecycline and vancomycin. A total of 287 drug-resistant strains were monitored, accounting for 13%, among which there were 128 carbapenem-resistant Acinetobacter baumannii strains, 88 carbapenem-resistant Pseudomonas aeruginosa strains, 26 carbapenem-resistant Klebsiella pneumoniae subspecies strains, 11 carbapenem-resistant Escherichia coli strains, 23 methicillin-resistant Staphylococcus aureus strains, and 11 vancomycin-resistant Enterococcus strains. The carbapenem-resistant Klebsiella pneumoniae subspecies strains mainly produced serine carbapenemase, and the carbapenem-resistant Escherichia coli strains mainly produced metal β-lactamase. Conclusion Gram-negative bacteria are the main pathogenic bacteria for infection after liver transplantation, and there are differences in the distribution of pathogenic bacteria between different types of specimens. The resistance rate of some strains tend to increase, and therefore, it is necessary to strengthen the management of nosocomial infection and antibiotics.

Acute lung injury (ALI), as a common clinical emergency, is pulmonary edema and diffuse lung infiltration caused by inflammation. The lack of non-invasive alert strategy, resulting in failure to carry out preventive treatment, means high mortality and poor prognosis. Stimulator of interferon genes (STING) is a key molecular biomarker of innate immunity in response to inflammation, but there is still a lack of STING-targeted strategy. In this study, a novel STING-targeted PET tracer, [¹⁸F]FBTA, was labeled with high radiochemical yield (79.7 ± 4.3%) and molar activity (32.5 ± 2.9 GBq/μmol). We confirmed that [¹⁸F]FBTA has a strong STING binding affinity (K_d = 26.86 ± 6.79 nmol/L) and can be used for PET imaging in ALI mice to alert early lung inflammation and to assess the efficacy of drug therapy. Our STING-targeted strategy also reveals that [¹⁸F]FBTA can trace ALI before reaching the computed tomography (CT) diagnostic criteria, and demonstrates its better specificity and distribution than [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG).

OBJECTIVE: To analyze the preservation effect and related influencing factors of human peripheral blood mononuclear cells under serum-free condition at 4 ℃. METHODS: Human peripheral blood mononuclear cells were isolated by density gradient centrifugation, and stored at 4 ℃ under different cell concentrations, supplemented with human serum albumin, and glucose. The cell viability, total cell number, viable cell number and cell phenotype were detected during preservation of 72 h. RESULTS: With the prolongation of storage time, the number of human peripheral blood mononuclear cells gradually decreased(r=0.982). Compared with the cell concentration of (5-6)×10⁶ cells/ml, the cell number decreased more slowly when the cell storage concentration was (1-2)×10⁶ cells/ml; Adding human serum albumin and glucose can effectively improve the survival rate of human peripheral blood mononuclear cells, among which 2% human serum albumin has a better preservation effect; Compared with the blank control group, the analysis results of cell subsets showed that the downward trends of NK cells and T cells were significantly slowed after adding albumin and glucose. CONCLUSION The cell density of (1-2)×10⁶/ml and 2% human serum albumin are more suitable for the preservation of PBMC, and 5% glucose can improve the preservation effect of human peripheral blood mononuclear cells at 4 ℃.
Humans ; Leukocytes, Mononuclear

BACKGROUND: Norepinephrine infusion decreases hypotension after spinal anesthesia during cesarean section. This study aimed to compare the efficacy of norepinephrine infusion and ephedrine bolus against post-spinal hypotension in parturients. METHODS: In this double-blinded, randomized controlled clinical trial, parturients scheduled for elective cesarean section were randomly allocated to receive norepinephrine infusion (0.05 μg·kg-1·min-1) just before spinal anesthesia continuing for 30 min or ephedrine bolus (0.15 mg/kg) just before spinal anesthesia. A rescue bolus (5 μg norepinephrine for the norepinephrine group, and 5 mg ephedrine for the ephedrine group) was administered whenever hypotension occurred. Our primary outcome was the incidence of hypotension within 30 min of spinal anesthesia administration. Secondary outcomes included maternal and neonatal outcomes 30 min after spinal block, and neonatal cerebral oxygenation 10 min after birth. RESULTS: In total, 190 patients were enrolled; of these patients, 177 were included in the final analysis. Fewer patients suffered hypotension in the norepinephrine group than in the ephedrine group (29.5% vs. 44.9%, odds ratio [OR]: 0.51, 95% confidence interval [CI]: 0.28-0.95, P = 0.034). Moreover, the tachycardia frequency was lower in the norepinephrine group than in the ephedrine group (OR: 0.22, 95% CI: 0.11-0.44, P < 0.001), and patients suffered less nausea and vomiting (OR: 0.28, 95% CI: 0.11-0.70, P = 0.004). There was no difference in Apgar scores and umbilical arterial blood gas analysis between the two groups. However, neonatal cerebral regional saturations were significantly higher after birth in the norepinephrine group than in the ephedrine group (mean difference: 2.0%, 95% CI: 0.55%-3.45%, P = 0.008). CONCLUSION: In patients undergoing elective cesarean section with spinal anesthesia, norepinephrine infusion compared to ephedrine bolus resulted in less hypotension and tachycardia, and exhibited potential neonatal benefits. TRIAL REGISTRATION ClinicalTrials.gov, NCT02542748; https://clinicaltrials.gov/ct2/show/record/NCT02542748.
Anesthesia, Spinal/adverse effects* ; Cesarean Section/adverse effects* ; Double-Blind Method ; Female ; Humans ; Hypotension/prevention & control* ; Infant, Newborn ; Phenylephrine ; Pregnancy ; Randomized Controlled Trials as Topic ; Vasoconstrictor Agents/therapeutic use*

OBJECTIVE: To investigate the effect of high mobility group protein 1(HMGB1) on the proliferation and cytokine expression of human bone marrow mesenchymal stem cells (MSC). METHODS: Different concentrations of recombinant human HMGB1 protein (100, 200, 400, 800 and 1000 ng/ml) were incubated with MSC for 24, 48, 72 h and the proliferation of MSC were detected respectively by using the CCK-8 method and flow cytometry. The best concentrations of HMGB1 incubated with MSC was determined (200 ng/ml, 1000 ng/ml), and the flow cytomerty was used to determine the effect of HMGB1 on the proliferation of MSC. The mRNA expression levels of IL-10, TGF- β1, TSG-6 and IFN-γ in MSC incubated with HMGB1 protein were detected by real-time quantitative PCR and ELISA. RESULTS: The result of MSC identification and flow cytometry showed that the CD105, CD73 and CD90 were expressed, but did not expression CD45, CD34, CD11b, CD19 and HLA-DR; CCK-8 showed that HMGB1 at the concentrations of 100 ng/ml, 200 ng/ml and 400 ng/ml could promote the proliferation of MSC incubated for 24, 48 and 72 h as compared with the control group (P<0.05), and the most effective concentration was 200 ng/ml; flow cytometry showed that the compared with the control group, HMGB1 200 ng/ml could induce MSC from G1 phase to S phase to promote the proliferation of MSC; QPCR showed that the mRNA expression of MSC cytokines IL-10, TGF-β1, TSG-6 increased while IFN-γ decreased at the concentration of 200 ng/ml HMGB1 as compared with the control group. ELISA experiments showed that the HMGB1 200 ng/ml acting on MSC for 48 h could significantly promoted the secretion of IL-10, TGF-β 1 and TSG-6(P<0．05), while IFN-γ showed no significant difference as compared with control group. CONCLUSION Recombinant human HMGB1 can promote the proliferation and secretion of MSC in healthy people.
Bone Marrow Cells ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; HMGB1 Protein ; Humans ; Mesenchymal Stem Cells

Objective:To investigate the effect of parallel double locking plate fixation on the postoperative trauma and bone metabolism in patients with distal humerus type C fracture.Methods:Retrospective analysis of clinical data of 75 patients with type C fracture of distal humerus admitted to the department of orthopedics, Baogang Hospital, Inner Mongolia from January 2017 to January 2019 was conducted. There were 46 males and 29 females, aged (45.14 ± 10.36) years and ranging from 22 to 69 years. According to the internal fixation method, they were divided into the control group ( n=36) and the observation group ( n=39). The control group was treated with Y-plate internal fixation, and the observation group was treated with parallel double locking plate fixation, which was compared with the operation time, intraoperative bleeding, fracture healing time and the excellent and good rate of elbow joint function of the two groups. The levels of LDH, ckeatine kinase, GPT, GOT, C3 and C4 were compared between the two groups. The bone metabolism indexes of the two groups were Osteocalcin, BALP, PINP, CTX and TRAP. The level of PYD and complications of the two groups were compared. The measurement data were expressed as mean±standard deviation ( Mean± SD), the t test was used for comparison between groups, and the count data were expressed as percentage (%), the chi-square test was used for comparison between groups. Results:There was no significant difference in operative time and intraoperative hemorrhage between the two groups ( P>0.05). The fracture healing time of the observation group was (10.22±2.16) weeks, shorter than that of the control group (13.63 ± 2.39) weeks, with a statistically significant difference ( P<0.05), the excellent and good rate of elbow joint function of the observation group was 82.05%(32/39), higher than that of the control group (61.11%, 22/36), with a statistically significant difference ( P<0.05). The levels of LDH, creatine kinase, GPT, GOT in the observation group were (205.36±20.51) U/L, (25.19±3.97) U/L, (11.37±2.04) U/L, (9.35±1.02) U/L, respectively, which were lower than those in the control group [(248.95±22.73) U/L, (41.85±4.64) U/L, (18.76±2.12) U/L, (16.68±1.34) U/L], complement C3 and C4 were (1.48 ± 0.16) g/L, (0.45 ± 0.07) g/L, which were higher than those of the control group [(1.15±0.14) g/L, (0.23±0.06) g/L], the difference was statistically significant ( P<0.05). Osteocalcin, BALP and PINP in the observation group were (6.27 ± 0.92) μg/L, (71.05 ± 7.46) IU/L, (92.39 ± 7.12) ng/mL, respectively, which were higher than those in the control group [(5.63 ± 0.76) μg/L, (64.82 ± 6.88) IU/L, (79.47 ± 8.64) ng/mL]. The levels of CTX, TRAP and PYD in the observation group were (5.52 ± 0.96) ng/mL, (3.47 ± 0.61) U/L, (25.07 ± 4.02) U/L, respectively, which were lower than those in the control group [(6.38 ± 0.99) ng/mL, (4.40 ± 0.73) U/L, (29.14 ± 3.85) U/L], with a statistically significant difference ( P<0.05), the incidence of postoperative complications in the observation group was 10.26% (4/39), lower than 30.56% (11/36) in the control group, with a statistically significant difference ( P<0.05). Conclusions:The treatment of C-type fracture of distal humerus with parallel double locking plate can improve the elbow joint function. The postoperative trauma is lighter, the bone metabolism is better, and it has more advantages than Y-type plate internal fixation, which is worth popularizing.