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Background@#Tigecycline, eravacycline, and omadacycline are recently developed tetracyclines. Susceptibility of microbes to these tetracyclines and their molecular mechanisms have not been well elucidated. We investigated the susceptibility of Moraxella catarrhalis to tigecycline, eravacycline, and omadacycline and its resistance mechanisms against these tetracyclines. @*Methods@#A total of 207 non-duplicate M. catarrhalis isolates were collected from different inpatients. The minimum inhibitory concentrations (MICs) of the tetracyclines were determined by broth microdilution. Tigecycline-, eravacycline-, or omadacycline-resistant isolates were induced under In Vitro pressure. The tet genes and mutations in the 16S rRNA was detected by PCR and sequencing. @*Results@#Eravacycline had a lower MIC50 (0.06 mg/L) than tigecycline (0.125 mg/L) or omadacycline (0.125 mg/L) against M. catarrhalis isolates. We found that 136 isolates (65.7%) had the tetB gene, and 15 (7.2%) isolates were positive for tetL; however, their presence was not correlated with high tigecycline, eravacycline, or omadacycline ( ≥ 1 mg/L) MICs.Compared with the initial MIC after 160 days of induction, the MICs of tigecycline or eravacycline against three M. catarrhalis isolates increased ≥ eight-fold, while those of omadacycline against two M. catarrhalis isolates increased 64-fold. Mutations in the 16S rRNA genes (C1036T and/or G460A) were observed in omadacycline-induced resistant isolates, and increased RR (the genes encoding 16SrRNA (four copies, RR1-RR4) copy number of 16S rRNA genes with mutations was associated with increased resistance to omadacycline. @*Conclusions@#Tigecycline, eravacycline, and omadacycline exhibited robust antimicrobial effects against M. catarrhalis. Mutations in the 16S rRNA genes contributed to omadacycline resistance in M. catarrhalis.
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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.
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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.
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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.
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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.
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<p><b>OBJECTIVE</b>To evaluate the expression and possible modulation of heme oxygenase-1 (HO-1) in nasal polyps of patients with chronic rhinosinusitis with nasal polyps (CRSwNP).</p><p><b>METHODS</b>Nasal polyps and uncinate process tissues were collected from 25 CRSwNP patients and 19 healthy controls with nasal septal deviation. HO-1 expression was examined using qRT-PCR, immunohistochemistric staining and Western blot analysis. Moreover, additional uncinate process mucosal samples of 15 healthy controls with nasal septal deviation were harvested for nasal explant culture experiments. HO-1 expression was measured in cultured nasal explant in response to specific inflammatory and glucocorticoid stimulation. SPSS 20.0 software was used to analyze the data.</p><p><b>RESULTS</b>The mRNA and protein expression of HO-1 was significantly increased in polyp tissues, 1.220±0.397 in mRNA and 1.409±0.701 in protein, compared with healthy controls 0.464±0.318 in mRNA and 0.017±0.1147 in protein (U=22.00 in mRNA and U=1.00 in protein, both P< 0.05). The immunohistochemical results showed that HO-1 was mainly distributed in the epithelial layer, submucosal glands and inflammatory cells in nasal tissues. Nasal explant culture experiments demonstrated that HO-1 mRNA was upregulated by IL-17A. The HO-1 mRNA level before the stimulation was 1.000, and 17.264±4.275 after the stimulation of 1 ng/ml IL-17A (U=0, P<0.05), 19.128±4.605 after the stimulation of 10 ng/ml IL-17A (U=0, P<0.05), but was significantly suppressed after stimulation with glucocorticoids (dexamethasone, DEX). The mRNA level after the glucocorticoids stimulation was 0.370±0.101 (U=0, P<0.05) and 0.316±0.167 (U=0, P<0.05) respectively. Furthermore, the HO-1 mRNA was inhibited by TGF-β1, the mRNA level was 0.217±0.322 (U=0, P<0.05), 0.070±0.070 (U=0, P<0.05), respectively.</p><p><b>CONCLUSION</b>Increased HO-1 expression may play a role in the pathogenesis of CRSwNP, which may be considered as the therapeutic target.</p>
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Humans , Blotting, Western , Case-Control Studies , Chronic Disease , Dexamethasone , Pharmacology , Glucocorticoids , Pharmacology , Heme Oxygenase-1 , Metabolism , Interleukin-17 , Pharmacology , Nasal Polyps , Metabolism , RNA, Messenger , Metabolism , Rhinitis , Metabolism , Sinusitis , Metabolism , Tissue Culture Techniques , Transforming Growth Factor beta1 , MetabolismABSTRACT
Objective To evaluate antimicrobial resistance and antimicrobial resistance mechanisms of Enterococcus faecalis (E.faecalis)to linezolid (LNZ),and provide basis for clinical rational drug use.Methods Twelve E.faecalis strains isolated from sputum of patients who received LNZ therapy in a hospital between January 2012 and January 2013 were collected.The minimum inhibitory concentrations (MICs)of antimicrobial agents were de-termined by agar dilution method,23S rRNA V region gene of E.faecalis was amplified by polymerase chain reac-tion,the amplified products were sequenced.Results Of 1 2 isolates,2 were intermediate strains and 1 0 sensitive strains.The G2576U mutation was detected in 2 intermediate strains,1 of which was also detected G2424U muta-tion;the variations were not detected in 10 sensitive strains.C2424U and G2576U mutation existed in R1 and R4 region respectively.Conclusion 23S rRNA V region gene mutations are found in the intermediate strains of E.faecalis.Change in MIC values of linezolid should be paid close attention in clinical use.
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<p><b>OBJECTIVE</b>To evaluate the effect of targeted percutaneous injection of medical ozone through the posterior approach via the spinal canal and dural sac under CT guidance for treatment of lumbar disc herniation.</p><p><b>METHODS</b>In 262 patients with lumbar disc herniation, medical ozone was injected percutaneously under CT guidance into the lumbar intervertebral disc by the posterior approach at paramedian 1-2 cm from the spinous process, targeting the affected lumbar discs, protruded nucleus pulposus and ipsilateral lateral recess. The concentration of ozone was 40-50 µg/ml in the disc/protruded nucleus pulposus and 30 µg/ml in the lateral recess (around the nerve root).</p><p><b>RESULTS</b>The treatment procedures were successfully completed in all the 262 patients. The average scores of JOA and VAS before treatment were 8.30∓1.4 and 8.73∓0.8, and changed significantly to 24.16∓3.2 (P=0.0158) and 2.41∓0.2 (P=0.0242) after treatment, respectively. According to the modified MacNab criteria, the therapeutic effect was excellent in 165 cases, fair in 64 cases, acceptable in 20 cases, and poor in 13 cases, with a total success rate of 87.4%. No patient showed serious complications after the treatment.</p><p><b>CONCLUSION</b>Compared with routine ozone therapy by the posterior-lateral approach, targeted percutaneous ozone injection into the intervertebral disc by the modified posterior approach is safe and yields better therapeutic effect for lumbar disc herniation.</p>
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Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Injections, Intralesional , Methods , Intervertebral Disc Displacement , Drug Therapy , Lumbar Vertebrae , Ozone , Spinal CanalABSTRACT
We first cloned the dsz operon of Pseudomonas delafieldii R-8 into the expressing plasmid (pPR9TT) to construct the recombinant plasmid pPR-dsz, and then reintroduced it into strain R-8 to obtain a muti-copy dsz operon engineering strain R-8-1. Compared with the wild-type, strain R-8-1 showed a higher desulfurization activity for dibenzothiophene (DBT). Initial rates of DBT removal by strain R-8-1 were 6.25 micromol/g dry cell/h, about 2-fold higher than that for wild-type strain. The recombinant cells were also applied in the desulfurization of diesel. It resulted in a 68% reduction of total sulfur from 310.8 mg/L to 100.1 mg/L, whereas only 53% of sulfur was removed by strain R-8. The stability of pPR-dsz in strain R-8-1 was studied. The results revealed the first obtain a muti-copy dsz operon engineering strain are helpful for further development in biodesulfurization.
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Bacterial Proteins , Genetics , Metabolism , Biodegradation, Environmental , Genetic Engineering , Genetic Enhancement , Methods , Operon , Oxygenases , Genetics , Protein Engineering , Methods , Pseudomonas , Genetics , Metabolism , Sulfur , Metabolism , Thiophenes , MetabolismABSTRACT
OBJECTIVE:To investigate the effect of arsenic trioxide(As2O3)on human hepatoma cells SMMC-7721 viability and the expression of urokinase plasminogen activator receptor(uPAR).METHODS:SMMC-7721 cells were cultured and treated with As2O3 at different concentrations for different time with untreated SMMC-7721 cells(without As2O3 treatment)served as control.The proliferation rate of the SMMC-7721 cells was measured by MTT assay;the change of cell cycle was detected by flow cytometry analysis;the effect of As2O3 on uPAR mRNA levels was analyzed by real-time fluorescent quantitative polymerase chain reaction.RESULTS:As2O3 had significant inhibitory effect on SMMC-7721 proliferation in time-dependent and concentration-dependent manner.As compared with control group,As2O3 significantly decreased the proportion of cells in G0/G1 phase but increased the cell proportion in G2/M phase,and it markedly down-regulated the level of uPAR mRNA expression(P
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@#目的调查警察院校实战训练损伤相关背景和损伤康复状况,了解致伤的危险因素。方法对公安大学和江西公专在警察实战训练过程中发生中度伤以上损伤的学员310人,采用自制运动损伤调查表对其损伤情况进行调查。结果重度伤发生的频率排序为运动比赛、擒敌课、课外体育锻炼、普体课和射击课;中度伤的排序为擒敌课、运动比赛、普体课、课外体育锻炼和射击课;伤后救护措施掌握的情况、紧张状况、性别和注意集中状况是影响运动损伤治疗效果的因素;是否预感发生损伤、损伤发生时的运动强度、中断警体训练的时间、重度伤发生的时间段和损伤前准备活动情况等变量显著影响损伤康复后的实战训练。在损伤康复手段上内服药物和中医疗法相对较好。结论实战训练损伤的重点损伤发生的状况与训练科目的运动学特征有联系,损伤的康复效果与致伤原因与个体训练特征和训练的组织、安排有关联。
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Objective To study the damage of liver function after transcatheter arterial chemoembolization (TACE) with low-dose versus conventional-dose anticancer drugs in patients with hepatocellular carcinoma (HCC). Methods One hundred and twelve patients with unresectable HCC were randomly divided into two groups (A and B) to receive superselective TACE. Low-dose anticancer drugs including mitomycin C (MMC) 2 ～ 8 mg, epirubicin (EPI) 5 ～ 10 mg and carboplatin (CBP) 100 mg were used in group A (n= 52), and conventional-dose of anticancer drugs (MMC 10 mg, EPI 40 mg and CBP 300 mg)for patients in group B(n= 60). Lipiodol-anticancer drugs emulsion was injected into the feeding arteries of tumor and then followed by embolization of gelatin sponge (GS) or polyvinyl alcohol (PVA) particles.Laboratory examination of the liver function including Child-Pugh scores, total bilirubin (TBIL), albumin (ALB) and alanine aminotransferase (ALT) were evaluated respectively before TACE and at third day, one week and four weeks after this procedure. Results In both groups, TBIL, ALT, and Child-Pugh scores increased (P ＜ 0.001 or P ＜ 0.05) and ALB decreased (P ＜ 0.001 or P ＜ 0.01) at three days and one week after TACE. Four weeks after-procedure, all the parameters described above showed no significant difference than those before the procedure in group A (P ＞ 0.05 ). On the contrary in group B, a significant difference (P ＜ 0.05) was found in the comparison of these parameters (except ALT). Conclusion Superselective TACE with low-dose anticancer drugs may induce transient impairment of liver function in the patients with HCC, but those patients used conventional-dose of anticancer drugs frequently cause lasting and more serious worsening of liver function.
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<p><b>OBJECTIVE</b>To study the effect of transcatheter arterial chemoembolization (TACE) combined with beta-ultrasound guided portal vein embolization (PVE) through fine-needle liver puncture for hepatocellular carcinoma.</p><p><b>METHODS</b>209 patients with primary hepatocellular carcinoma were divided into TACE group (104 patients) and TACE + PVE group (105 patients).</p><p><b>RESULTS</b>The response rates (CR + PR) were 37.5% in TACE group and 57.2% in TACE + PVE group (P < 0.01). Tumor thrombi became lessened or resolved in the portal vein with incidences of 22.2% in TACE group and 68.8% in TACE + PVE group (P < 0.01). The 1-, 2- and 3-year survival rates were 65.1%, 36.3% and 20.5% in TACE group and 95.6%, 59.6% and 39.1% in TACE + PVE group (P < 0.05).</p><p><b>CONCLUSION</b>The effect of TACE combined with PVE is much more effective than TACE alone for hepatocellular carcinoma. Beta-ultrasound guided portal vein embolization through fine-needle liver puncture is effective, easy, safe and should be widely practiced.</p>
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Adult , Aged , Female , Humans , Male , Middle Aged , Arteries , Carcinoma, Hepatocellular , Drug Therapy , Metabolism , Pathology , Therapeutics , Catheterization , Chemoembolization, Therapeutic , Methods , Follow-Up Studies , Liver Neoplasms , Drug Therapy , Metabolism , Pathology , Therapeutics , Portal Vein , Treatment Outcome , alpha-Fetoproteins , MetabolismABSTRACT
Purpose:To evaluate the efficacy of treating malignant pleural effusion with S 311 anticancer vaccine by intrapleural injection.Methods:62 cases with malignant pleural effusion,after drainage, S 311 anticancer vaccine 0.16 mg was injected into the pleural cavity in therapy group (T),and cisplatine 40 mg/m 2 in control group (C).The treatment was repeated after a week , then the efficacy, quality of life, survival rate and toxicities was evaluated.Results:The response rate was 90.6% in T group and 60.0% in C group. There was statistical difference between the two groups ( P
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Objective To evaluate the curative effect and optimal indications of reformed percutaneous lumbar diskectomy (RPLD) for the treatment of lumbar disc herniation.Methods One handred and thirty-three patients with lumbar disc herniation were treated by RPLD, of them, 20 cases were lumbar disc extrusion and 113 cases were lumbar disc protrusion. After the procedure, 85 patients underwent flush of intervertebral space with antibiotic saline and 48 patients underwent 10 ml(40?g/ml) medical ozone-injection inside the disc to prevent infection. All patients were followed up over the course of 3 months. The therapeutic effect was evaluated according to the MacNab criteria. Results All 133 cases underwent RPLD were successful. The total efficacy was 81.9%, There were no serious complications after operations. Conclusion RPLD is an effective method in the treatment of lumbar disc herniation. Both intradiscal ozone-injection or intradiscal antibiotic saline flush after RPLD can reduce the opportunity of infection.
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Objective To explore the relationship between chronic severe hepatitis and cryptosporidium infection to provide evidences for scientific prevention and treatment of chronic severe hepatitis. Methods Fecal samples of 218 patients with chronic severe hepatitis B (CSHB) and 140 children with diarrhea were collected, and were examined for cryptosporidium oocytes by using auramine-phenol staining method (AA-p) and modified acid-fast staining method (MAF), and for cryptosporidium DNA by PCR and restriction digestion analysis. The factors affecting cryptosporidium infection of patients with CSHB were preliminarily analyzed. Results The positive rates of cryptosporidium infection detected by AA-p, MAF and PCR in the patients with CSHB and children with diarrhea were 4.1%, 3.2%, 6.0% and 0.7%, 0.7%, 1.4%, respectively. The positive rate of cryptosporidium infection detected by PCR in patients with CSHB was higher than that in children with diarrhea (P
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The earliest and the most common metastasis of hepatocellular carcinoma (HCC) occur in the intrahepatic portal venous system, which indicates its worst prognosis. In 28 HCC patients with intraportal tumor thrombus, we employed 2 procedures, ie. the transcatheter hepatic arterial embolization(THAE), transcatheter superior mesenteric or splenic arterial infusion (TSAI) and portal vein embolization (PVE) in 12 cases, and THAE alone in 16 cases. In the former group, tumor size reduced more than 50% in 8 cases (partial remission PR), in particular tumor thrombus disappeared in 3 and decreased in size in 8; whereas in the latter group, PR was achieved in 3 only, without change size of the intraportal tumor thrombus in all 16 cases (P