1.Third-generation cephalosporin resistance in gram-negative bacteria in the community: a growing public health concern.
The Korean Journal of Internal Medicine 2014;29(1):27-30
No abstract available.
Bacteremia/*microbiology
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*Cephalosporin Resistance
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Escherichia coli/*physiology
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Female
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Humans
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Klebsiella pneumoniae/*physiology
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Male
2.Effects of Scutellaria Baicalensis on Activity and Biofilm Formation of Klebsiella Pneumoniae.
Wei CHEN ; Bei LI ; Shuai LI ; Yi-Wen OU ; Qin OU
Chinese Medical Sciences Journal 2016;31(3):180-184
Objective To explore the effects of Scutellaria baicalensis on activity and biofilm formation of Klebsiella pneumonia (Kp).Methods The broth and agar dilution Methods were carried out to determine minimum inhibitory concentration and minimum bactericidal concentration of Scutellaria baicalensis for TW518. VITEK-32 system was used to assay TW518 susceptibility to antibiotics. Kp biofilms were formed in vitro and stained with BacLight Live/Dead stain. The class integron geneⅠ1 mRNA expression was analyzed with RT-PCR.Results The minimum inhibitory concentration of Scutellaria baicalensis on TW518 identified as a Kp colony was 32 mg/ml, and minimum bactericidal concentration was 64 mg/ml. Scutellaria baicalensis and broad-spectrum penicillin, cephalosporin, quinolones, or beta-lactamase had synergistic bactericidal effects. Biofilm formation activity of Kp treated with Scutellaria baicalensis was significantly lower than that of the control group. And class integron geneⅠ1 mRNA expression of TW518 was significantly inhibited by Scutellaria baicalensis.Conclusions Scutellaria baicalensis has sterilization effect on Kp, and Scutellaria baicalensis could effectively inhibit Kp biofilm formation with prolonged treatment. Scutellaria baicalensis might inhibit Kp biofilm formation through down-regulating integron geneⅠ1 expression.
Biofilms
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drug effects
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Integrons
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drug effects
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Klebsiella pneumoniae
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drug effects
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physiology
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Microbial Sensitivity Tests
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Scutellaria baicalensis
4.Preliminary study on the role of novel LysR family gene kp05372 in Klebsiella pneumoniae of forest musk deer.
Wei YANG ; Wu-You WANG ; Wei ZHAO ; Jian-Guo CHENG ; Yin WANG ; Xue-Ping YAO ; Ze-Xiao YANG ; Dong YU ; Yan LUO
Journal of Zhejiang University. Science. B 2020;21(2):137-154
LysR-type transcriptional regulators are involved in the regulation of numerous cellular metabolic processes in Klebsiella pneumoniae, leading to severe infection. Earlier, we found a novel LysR family gene, named kp05372, in a strain of K. pneumoniae (designated GPKP) isolated from forest musk deer. To study the function of this gene in relation to the biological characteristics of GPKP, we used the suicide plasmid and conjugative transfer methods to construct deletion mutant strain GPKP-Δkp05372; moreover, we also constructed the GPKP-Δkp05372+ complemented strain. The role of this gene was determined by comparing the following characteristics of three strains: growth curves, biofilm formation, drug resistance, stress resistance, median lethal dose (LD50), organ colonization ability, and the histopathology of GPKP. Real-time polymerase chain reaction (RT-PCR) was used to test the expression level of seven genes upstream of kp05372. There was no significant difference in the growth rates when comparing the three bacterial strains, and no significant difference was recorded at different osmotic pressures, temperatures, salt contents, or hydrogen peroxide concentrations. The GPKP-Δkp05372 mutant formed a weak biofilm, and the other two strains formed medium biofilm. The drug resistance of the GPKP-Δkp05372 mutant toward cephalothin, cotrimoxazole, and polymyxin B was changed. The acid tolerance of the deletion strain was stronger than that of the other two strains. The LD50 values of the wild-type and complemented strains were 174-fold and 77-fold higher than that of the GPKP-Δkp05372 mutant, respectively. The colonization ability of the GPKP-Δkp05372 mutant in the heart, liver, spleen, kidney, and intestine was the weakest. The three strains caused different histopathological changes in the liver and lungs. In the GPKP-Δkp05372 mutant, the relative expression levels of kp05374 and kp05379 were increased to 1.32-fold and 1.42-fold, respectively, while the level of kp05378 was decreased by 42%. Overall, the deletion of kp05372 gene leads to changes in the following: drug resistance and acid tolerance; decreases in virulence, biofilm formation, and colonization ability of GPKP; and regulation of the upstream region of adjacent genes.
Animals
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Bacterial Proteins/physiology*
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Biofilms
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Deer/microbiology*
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Drug Resistance, Bacterial
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Female
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Klebsiella Infections/pathology*
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Klebsiella pneumoniae/growth & development*
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Male
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Mice
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Transcription Factors/physiology*
5.1, 3-propanediol production under salt stress.
Jiajie XU ; Pengbo LIU ; Chunping TAO ; Cheng CHENG ; Shuilin FU ; Heng GONG
Chinese Journal of Biotechnology 2008;24(6):1098-1102
Through studying the process of glycerol fermentation to 1, 3-propanediol(1, 3-PD) by Klebsiella pneumoniae, it was found that the cell growth and product (or by-product) production were under salt stress. Cell growth and product formation kept high rate at low salt concentration. High salt concentration led to low growth of cells, final concentration of 1, 3-PD and conversion from glycerol to 1, 3-PD, and, 1, 3-propanediol oxidoreductase activity decreased. When the salt concentration in 5 m3 bioreactor was controlled under appropriate manner, the concentration of 1, 3-PD production was markedly enhanced. The final 1, 3-PD concentration ,the conversion of glycerol to 1, 3-PD and productivity were 64 g/L, 61% and 2.1 g/(L x h).
Alcohol Dehydrogenase
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Alcohol Oxidoreductases
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metabolism
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Culture Media
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Culture Techniques
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Fermentation
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Glycerol
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metabolism
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Klebsiella pneumoniae
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growth & development
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metabolism
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physiology
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Propylene Glycols
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metabolism
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Sodium Chloride
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pharmacology
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Stress, Physiological
6.The First Case of Septicemia Caused by Imipenem-Susceptible, Meropenem-Resistant Klebsiella pneumoniae.
Shizuo KAYAMA ; Norifumi SHIGEMOTO ; Ryuichi KUWAHARA ; Takashi ISHINO ; Kentaro IMON ; Makoto ONODERA ; Michiya YOKOZAKI ; Hiroki OHGE ; Motoyuki SUGAI
Annals of Laboratory Medicine 2013;33(5):383-385
No abstract available.
Aged
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Drug Resistance, Bacterial
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Humans
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Imipenem/pharmacology/therapeutic use
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Klebsiella Infections/diagnosis/drug therapy/*microbiology
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Klebsiella pneumoniae/drug effects/isolation & purification/*physiology
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Male
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Microbial Sensitivity Tests
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Phenotype
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Sepsis/diagnosis/drug therapy/*microbiology
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Thienamycins/pharmacology/therapeutic use
7.A Five-year Surveillance of Carbapenemase-producing Klebsiella pneumoniae in a Pediatric Hospital in China Reveals Increased Predominance of NDM-1.
Fang DONG ; Jie LU ; Yan WANG ; Jin SHI ; Jing Hui ZHEN ; Ping CHU ; Yang ZHEN ; Shu Jing HAN ; Yong Li GUO ; Wen Qi SONG ;
Biomedical and Environmental Sciences 2017;30(8):562-569
OBJECTIVETo characterize carbapenem (CPM)-non-susceptible Klebsiella pneumoniae (K. pneumoniae) and carbape-nemase produced by these strains isolated from Beijing Children's Hospital based on a five-year surveillance.
METHODSThe Minimal Inhibition Concentration values for 15 antibiotics were assessed using the Phonix100 compact system. PCR amplification and DNA sequencing were used to detect genes encoding carbapenemases. WHONET 5.6 was finally used for resistance analysis.
RESULTSIn total, 179 strains of CPM-non-susceptible K. pneumoniae were isolated from January, 2010 to December, 2014. The rates of non-susceptible to imipenem and meropenem were 95.0% and 95.6%, respectively. In the 179 strains, 95 (53.1%) strains carried the blaIMP gene, and IMP-4 and IMP-8 were detected in 92 (96.8%) and 3 (3.2%) IMP-producing isolates, respectively. 65 (36.3%) strains carried the blaNDM-1 gene. 6 (3.4%) strains carried the blaKPC gene, and KPC-2 were detected in 6 KPC-producing isolates. In addition, New Delhi-Metallo-1 (NDM-1) producing isolates increased from 7.1% to 63.0% in five years and IMP-4 producing isolates decreased from 75.0% to 28.3%.
CONCLUSIONHigh frequencies of multiple resistances to antibiotics were observed in the CPM-non-susceptible K. pneumoniae strains isolated from Beijing Children's Hospital. The production of IMP-4 and NDM-1 metallo-β-lactamases appears to be an important mechanism for CPM-non- susceptible in K. pneumoniae.
Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Child ; China ; epidemiology ; Drug Resistance ; Gene Expression Regulation, Bacterial ; physiology ; Gene Expression Regulation, Enzymologic ; physiology ; Hospitals, Pediatric ; Humans ; Klebsiella Infections ; epidemiology ; microbiology ; Klebsiella pneumoniae ; drug effects ; enzymology ; genetics ; Microbial Sensitivity Tests ; Population Surveillance ; Time Factors ; beta-Lactamases ; genetics ; metabolism
8.Transconjugation and genotyping of the plasmid-mediated AmpC beta-lactamase and extended-spectrum beta-lactamase genes in Klebsiella pneumoniae.
Wei-feng SHI ; Jun ZHOU ; Jian-ping QIN
Chinese Medical Journal 2009;122(9):1092-1096
BACKGROUNDAmpC beta-lactamases and extended-spectrum beta-lactamases (ESBLs) are becoming predominant causes of resistance to third and forth-generation cephalosporins in Klebsiella pneumoniae (K. pneumoniae). It is very difficult to treat infectious diseases caused by multidrug-resistant K. pneumoniae. The purpose of the present study was to investigate transconjugation and characteristics of beta-lactamase genes in K. pneumoniae producing AmpC beta-lactamases and ESBLs.
METHODSAmpC beta-lactamases were detected by three-dimension test and ESBLs by disc confirmatory test. Minimum inhibitory concentrations (MICs) were determined by agar dilution. Transfer of resistance to EC600 (Rif(r)) was attempted by conjugation in broth and screened on agar containing cefotaxime (2 microg/ml) plus rifampin (1024 microg/ml). The genes encoding AmpC or ESBLs and their transconjugants were detected by PCR and verified by DNA sequencing.
RESULTSThe resistant rates to ampicillin and piperacillin were 100% in 18 isolates of K. pneumoniae. However, imipenem was still of great bactericidal activity on K. pneumoniae, and its MIC(50) was 0.5 microg/mL. Eleven beta-lactamase genes, including TEM-1, TEM-11, SHV-13, SHV-28, CTX-M-9, CTX-M-22, CTX-M-55, OXA-1, LEN, OKP-6 and DHA-1, were found from 18 isolates. And at least one beta-lactamase gene occurred in each isolate. To our surprise, there were six beta-lactamase genes in the CZ04 strain. Among 18 isolates of K. pneumoniae, the partial resistant genes in 8 isolates were conjugated successfully, which had 100% homological sequence with donors by sequence analysis. Compared with donors, 8 transconjugants had attained resistance to most beta-lactams, including ampicillin, piperacillin, cefoxitin, cefotaxime and aztreonam, or even amikacin and gentamicin.
CONCLUSIONSR plasmids can be easily transferred between the resistant and sensitive negative bacilli. It is very difficult to block and prevent the spread of antimicrobial resistance. So more attention should be paid to reducing the frequency, times and dosage of antimicrobials, especially third or fourth cephalosporins.
Ampicillin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; physiology ; Cefotaxime ; pharmacology ; Conjugation, Genetic ; genetics ; physiology ; Drug Resistance, Multiple, Bacterial ; genetics ; Genotype ; Imipenem ; pharmacology ; Klebsiella pneumoniae ; drug effects ; genetics ; Microbial Sensitivity Tests ; Piperacillin ; pharmacology ; Plasmids ; genetics ; physiology ; Rifampin ; pharmacology ; beta-Lactamases ; genetics ; physiology
9.Third-generation cephalosporin resistance of community-onset Escherichia coli and Klebsiella pneumoniae bacteremia in a secondary hospital.
Shinwon LEE ; Seung Woo HAN ; Kun Woo KIM ; Do Young SONG ; Ki Tae KWON
The Korean Journal of Internal Medicine 2014;29(1):49-56
BACKGROUND/AIMS: To enable appropriate antimicrobial treatment for community-onset infections in emergency departments (EDs), data are needed on the resistance profiles of Escherichia coli and Klebsiella pneumoniae, which are the main pathogens of community-onset bacteremia. METHODS: Records were reviewed of 734 patients with E. coli and K. pneumoniae bacteremia who visited the Daegu Fatima Hospital ED, Daegu, Korea between 2003 and 2009. We investigated the demographic data, clinical findings, and antimicrobial susceptibility patterns of the organisms. RESULTS: Of 1,208 cases of community-onset bacteremia, 62.8% were caused by E. coli or K. pneumoniae in an ED of a secondary care hospital. Five hundred and forty-eight cases of E. coli (75%) and 183 cases of K. pneumoniae (25%) were analyzed. Urinary tract infection (43.1%) was most common, followed by intra-abdominal infection (39%) and pneumonia (7.2%). Trimethoprim/sulfamethoxazole, fluoroquinolone, third-generation cephalosporin (3GC) and amikacin resistance rates among E. coli and K. pneumoniae were 22.8%, 19.6%, 6.2%, and 1.3%, respectively. In 2009, the rate of 3GC resistance (10.6%) was significantly higher, compared to the annual averages of 2003 to 2008 (6.1%; p = 0.03). Previous exposure to antibiotics was an independent risk factor for 3GC resistance in multivariate logistic regression analysis. CONCLUSIONS: The rate of 3GC resistance increased in community-onset infections, and previous exposure to antibiotics was an independent risk factor. Despite the increased 3GC resistance in community-onset infections, an amikacin combination therapy could provide an option for treatment of bacteremic patients with previous antibiotic exposure in an ED.
Aged
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Aged, 80 and over
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Bacteremia/epidemiology/*microbiology
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*Cephalosporin Resistance
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Community-Acquired Infections/microbiology
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Emergency Service, Hospital/statistics & numerical data
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Escherichia coli/*physiology
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Female
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Humans
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Klebsiella pneumoniae/*physiology
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Male
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Middle Aged
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Republic of Korea/epidemiology
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Retrospective Studies
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Secondary Care Centers/statistics & numerical data
10.Effect of jinqiaomai on expression of TLR2/4, MyD88 mRNA and IkappaB-alpha in lung tissue of rats with Klebsiella pneumonia.
Liuyi DONG ; Chunyan WANG ; Changqing WU ; Qin JIANG ; Zhifen ZHANG
China Journal of Chinese Materia Medica 2011;36(2):200-204
OBJECTIVETo study the mechanism of protective effect of Jinqiaomai (JQM) on lung injury induced by Klebsiella pneumonia in rats.
METHODThe model of rats with Klebsiella pneumonia was established. The male SD rats were randomly divided into control group, model group, JQM (6, 3, 1.5 g x kg(-1)) three groups, levofloxacin (25 mg x kg(-1)) group, JQM (3 g x kg(-1)) + levofloxacin (25 mg x kg(-1)) group. The contents of IL-1beta, ICAM-1 and INF-gamma in the lung tissue homogenate were measured by radio-immunoassay and Elisa. TLR2/4 mRNA and MyD88 mRNA expression were detected by RT-PCR. IkappaB-alpha expression was detected by Western Blot.
RESULTThe rats of model group had obvious lung injury, but those of JQM, JQM + levofloxacin and levofloxacin groups had less injury. The contents of IL-1beta, ICAM-1 and INF-gamma in lung tissue homogenate and the expressions of TLR2/4 mRNA, MyD88 mRNA and IkappaB-alpha in lung of model group were significantly higher than those in the control group (P < 0.05 or P < 0.01), while IL-1beta, ICAM-1 and INF-gamma of JQM groups were significantly lower than those of model group (P < 0.05 or P < 0.01). The expressions of TLR2/4 mRNA, MyD88 mRNA and IkappaB-alpha of JQM (6.3 g x kg(-1)) groups were significantly lower than those of model group(P <0. 05 or P <0. 01).
CONCLUSIONThe lung injury induced by Klebsiella pneumonia is related to TLR2/4, MyD88 mRNA and IkappaB-alpha. To decrease the excessive expression of TLR2/4, MyD88 mRNA and IkappaB-alpha might be the main mechanism of protective effect of Jinqiaomai on lung injury.
Animals ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; Gene Expression ; drug effects ; Humans ; I-kappa B Proteins ; genetics ; metabolism ; Klebsiella Infections ; drug therapy ; genetics ; metabolism ; microbiology ; Klebsiella pneumoniae ; drug effects ; physiology ; Lung ; drug effects ; metabolism ; microbiology ; Male ; Myeloid Differentiation Factor 88 ; genetics ; metabolism ; NF-KappaB Inhibitor alpha ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Toll-Like Receptor 2 ; genetics ; metabolism ; Toll-Like Receptor 4 ; genetics ; metabolism