1.Molecular Epidemiology of Staphylococcus aureus Originated from Respiratory Tract of Patients after Transplantation
Hui HUANG ; Rujun AN ; Jiandang ZHOU ; Xiuping ZHOU
Chinese Journal of Nosocomiology 2006;0(02):-
OBJECTIVE To know the gene type of Staphylococcus aureus which caused the respiratory tract infection of patients after transplantation in our hospital,and to explore the epidemiology,preventing measure and nursing strategy of the lung infection by S.aureus among them.METHODS Using random amplified polymorphic DNA(RAPD) to analyze the gene type fingerprint of the 20 S.aureus strains originated from the respiratory tract of patients after transplantation,and using cefoxitin paper strip method to detect the mecA gene of the S.aureus.RESULTS Twenty S.aureus strains were divided into 8 gene types,and among them,the detectable rate of gene types Ⅰ,Ⅱ,and Ⅲ was 40.0%,15.0%,and 15.0%,respectively.The positive rate of mecA gene reached to 80.0%.CONCLUSIONS The S.aureus originated from respiratory tracts of the patients after transplantation is mainly of gene type Ⅰ.And the positive rate of mecA gene is very high.So the management of hands washing,sterilization and isolation of medical and nursing staffs should be strengthened,and effective method should be took to prevent the propagation of mecA positive S.aureus among the patients after transplantation.
2.Clinical Study of Aerosol Transmission in Two Oxygen Humidifiers
Hui HUANG ; Rujun AN ; Qifeng YI ; Jiandang ZHOU
Chinese Journal of Nosocomiology 2009;0(21):-
OBJECTIVE In order to find the way to reduce nosocomial pneumonia through preventing delivery of microbio-aerosol.we investigate whether oxygen humidification process generate and deliver aerosol to the end of oxygen tube,and the difference between two types of humidifier.METHODS Two types of humidifier were used.One was unique bionic humidifier through surface of humidification material,the other was conventional bubble humidifier.The amount of aerosol was counted by laser particle counter at the end of oxygen cannula.Different solute of ferric chloride and soluble starch in two humidification materials were used to testify the generation and transmission of aerosol during oxygen therapy.RESULTS Bubble humidifier produced large amount of aerosol of 0.3,0.5,1.0,3.0,5.0 ?m at 31089.9、28488.6、2873.9、197、1.1particle/cubic meter respectively.Most of the aerosol were between 0.3 and 3 microns in diameter.While bionic humidifier produced small amount of aerosol of 0.3,0.5,1 ?m at 95.3,39.8,2.0 particle/cubic meter respectively,there were no aerosol particle larger than 3?m.The difference of 0.3,0.5,1.0,3.0,5.0?m aerosol between bubble and bionic humidifier was significant(P
3.Infectious pathogen’s drug-resistance after liver transplantation
Jiandang ZHOU ; Shaihong ZHU ; Jianjun GUO
Chinese Journal of Organ Transplantation 2005;0(08):-
Objective To study the main infectious bacteria and their drug-resistance after liver tra nsplantation. Methods K-B method was used to detect the susceptibility of agents of the main bacteria after liver transplantation. ESBLs and AmpC ?-lactamase among the main negati ve bacillus were detected by three-dimensional tests. ?-lactamase and Van gen e among Enterococcus were dectected by standard agar dilution susceptibility tes ts and Nitrocefin respectively. Results Among the main Gram-negative bacteria in 55 cases of infection following liver transplantation, the ratio of resistance to 4 or more antibiotic were all beyond 40% . The detectable rate of ESBLs and AmpC ?-lactamases in Enterobacter cloacae and Escherichia coli was 32.4% and 36.8% , and 33.8% and 10.5% re spectively. Moreover, the detectable rate of both ESBLs and AmpC ?-lactamases in Enterobacter cloacae and Escherich ia coli was 24.3% and 7.0% repectively. 8.8% and 11.1% produced ?-lactamases in Enterococcus faec alis and Enterococcusfaecium, with the ratio of resistance to Vancomycin being 11.2% and 18.5% respectively. Conclusions The primary pathogens have the high and multiple resistance to antimicrobial aft er liver transplantation. ESBLs and AmpC ?-lactamases were the main two factor s of drug-resistance among Gram-negative bacillus. we should pay much attentio n to the high detectble rate of Enterococcus which are resistant to Vancomycin a fter liver transplantation.
4.Manifestation, distribution of pathogen, and resistance of bloodstream infections after renal transplantation:clinical anylasis of 71 patients
Qiquan WAN ; Jingle LI ; Qifa YE ; Jiandang ZHOU
Journal of Central South University(Medical Sciences) 2013;38(9):938-943
Objective:To investigate the clinical manifestation and determine the distribution of pathogens and their characteristics of drug susceptibility to bloodstream infections (BSIs), and provide evidence for clinical anti-infection treatments after renal transplantation.
Methods:Totally 81 episodes of BSIs occurred in 71 patients between July 2003 and June 2013. We retrospectively analyzed the pathogens and their drug susceptibility characteristics with BD microbiological assay system. We also collected the clinical and laboratory data of the patients . Results:The main pathogens were gram negative bacteria (67.90%), followed by gram positive bacteria (28.40%) and fungi (3.70%). The most common gram negative bacillus was Escherichia coli.While for gram positive bacteria, the main bacillus was coagulase-negative staphylococci. The gram negative bacteria were relatively sensitive to aminoglycosides and carbapenem. The gram positive bacteria were sensitive to glycopeptides and oxazolidone.
Conclusion:The clinical manifestations included high body temperature, onset in the early period after kidney transplantation and high mortality. Though gram positive coccus plays an important role, most infections are caused by gram negative bacteria in BSIs after the renal transplantation. The antibiotic resistant rate for gram negative bacteria is very high as well as gram positive bacteria.
5.Detection of Different Genotyping of ?-Lactamases and Drug Resistance in Enterobater cloacae
Huayu GONG ; Zhenguo LIU ; Jiandang ZHOU ; Limin CHEN ; Haoye ZHANG
Chinese Journal of Nosocomiology 2009;0(15):-
OBJECTIVE To investigate the prevalence of ?-lactamases in nosocomial infections of Enterobacter cloacae,study the different genotyping of ?-lactamases,and analyze its independence in drug resistance. METHODS AmpC ?-lactamases and ESBLs were detected by three-dimensional extract tests.PCR was used to determine the genotype of ?-lactamases and their resistance to 13 kinds of antibiotics was detected by Kirby-Bauer method. RESULTS The sensitivity test showed that they were resistant to the most antibiotics.Among the 80 ESBLs strains,29 strains carried ESBLs gene,3 strains carried two different gene.Such as:TEM existed in 6,SHV-Ⅰ existed in 2,CTX-M-2 existed in 5,CTX-M-3 existed in 8 and CTX-M-9 existed in 11 strains.Twenty-six strains carried ampC.The resistant rate of SSBLs-producing E.cloacae to 12 antibiotics except merapenem was 66.7-100.0%.SSBLs strains of E.cloacae were higher than AmpC ?-lactamases in resistance to levofloxacin,cefepime,aztronem and trimethoprim sulpfamethoxazole with significant difference(P
6.Risk factors of bloodstream infection-related death after liver transplantation
Qiquan WAN ; Jianfei XIE ; Shaojun YE ; Zhongzhong LIU ; Fushun ZHONG ; Jiandang ZHOU ; Qifa YE
Chinese Journal of Digestive Surgery 2016;15(5):471-476
Objective To investigate the risk factors of bloodstream infection-related death after liver transplantation.Methods The retrospective case-control study was adopted.The clinical data of the 107 patients with bloodstream infection from 365 liver transplantation patients who were admitted to the Third Xiangya Hospital of Central South University (220 patients) and South Central Hospital Affiliated to Wuhan University (145 patients) from January 1,2002 to December 31,2015 were collected.The patients received modified piggyback liver transplantation.The second or third generation celphalosporin or carbapenems antibiotics were preventively used against infection according to the bacterial culture results before surgery,and the immune inhibitor basic program after surgery was FK506 + prednisone.The observation indicators included:(1) the bloodstream infection status after liver transplantation:incidence of bloodstream infection,frequency of bloodstream infection,inadequate antiinfection treatment,primary infection position,microorganism infection type,bacterial culture results and bloodstream infection-related mortality.(2) The risk factors of blood stream infection-related death after liver transplantation in univariate and multivariate analyses in cluded:the gender,age,resource of donor,usage of immune inhibitor,time between infection and liver transplantation,infection temperature,primary infection position(intraperitoneal or biliary infection),pathogenic microorganism type,nosocomial infection,inadequate antibiotic usage,serum creatinine level,serum albumin (Alb) level,white blood cell (WBC) in peripheral blood,lymphocyte in peripheral blood,platelet (PLT) in peripheral blood and septic shock indexes.The patients were followed up by outpatient examination and telephone interview up to January 31,2016,the follow-up contents included the survival status of the patients,vital signs,using status of immune inhibitor,immune inhibitor concentration,blood routine,biochemical indexes,surgery,other infection-related complications and acute rejection.Continuous variables with normal distribution were represented as ~ ± s.The univariate analysis was done by the Chi-square test.The multivariate analysis was done by the Logistic regression model.Results (1) The bloodstream infection status after liver transplantation:186 bloodstream infections were happened in 107 patients undergoing liver transplantation,with a total incidence of bloodstream infection of 29.32% (107/365).The incidence of bloodstream infection was 28.18% (62/220) in the Third Xiangya Hospital of Central South University and 31.03% (45/145) in the South Central Hospital Affiliated to Wuhan University,with no statistical difference (x2=0.186,P >0.05).Of 107 patients,56 patients had once bloodstream infection,31 had twice bloodstream infection and 20 had three times or more bloodstream infection (frequency of the most bloodstream infection was 6).The inadequate anti-infection treatment was applied to the 41.12% (44/107)of patients with liver transplantation and bloodstream infection.The number of patients with primary infection positions in abdomen,lung,urethra,intravascular catheter and unknown sites were 40,39,3,1 and 24,respectively.The Gram positive bacteria,Gram negative bacteria,fungus and mixed infection of microorganism infection type were detected in 28,24,4 and 51 patients,respectively.There were 102 patients with nosocomial infection.Bacteria culture results in 186 strains of blood sample illustrated:84 strains were Gram positive bacteria as major pathogenic bacteria,among which enterococcus (31 strains) and staphylococcus aureus (23 strains) were dominant strains.The bloodstream infection-related mortality was 37.38% (40/107),including 35 patients dying of septic shock.(2) The univariate analysis showed that the gender,resource of the donor,infection temperature,type of microorganism,serum creatinine level,serum Alb level,WBC in peripheral blood,PLT in peripheral blood and septic shock were the risk factors affecting bloodstream infection-related death after liver transplantation (x2=5.801,5.920,13.047,12.776,11.366,7.976,25.173,9.289,51.905,P <0.05).The multivariate analysis showed that serum Alb level < 30 mg/L and septic shock were the independent risk factors affecting bloodstream infection-related death after liver transplantation (OR =5.839,44.983,95 % confidence interval:1.145-29.767,12.606-160.514,P < 0.05).Conclusion It is prone to happen bloodstream infection after liver transplantation,and serum Alb level < 30mg/L and septic shock are the independent risk factors affecting bloodstream infection-related death after liver transplantation.
7. The effect of downregulation of MCT1 on the proliferation of glioma cells
Hanguang ZHOU ; Jiandang ZHANG ; Yuanfeng ZHANG
Chinese Journal of Oncology 2019;41(3):208-213
Objective:
To investigate the molecular mechanism of down-regulation of monocarboxylic acid transporter 1 (MCT1) on the proliferation inhibition of glioma cell.
Methods:
siMCT1, siMCT4 and negative control siRNA were transfected into glioma cell lines including U-251 and U-87. The proliferation activities of U-251 and U-87 cells were detected by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay and clonogenic assay. Glucose consumption and lactic acid efflux of U-251 and U-87 cells were determined by spectrophotometry.Western blot was used to detect the expressions of MCT1, MCT4, human glucose transporter 1 (GLUT1), GLUT4, tuberous sclerosis associated protein (TSC2), p-TSC2, 4E binding protein 1 (4EBP1), p-4EBP1, ribosomal S6 protein kinase (S6) and p-S6 protein in U-251 and U-87 cells.
Results:
Compared with negative control group, siMCT1 and siMCT4 significantly inhibited the expressions of MCT1 and MCT4 protein in U-251 and U-87 cells (both
8.Analysis of the relationship between the MecA gene and resistance of β-lactam antibiotics.
Hui HUANG ; Jiandang ZHOU ; Xinmin NIE ; Qifeng YI
Journal of Central South University(Medical Sciences) 2012;37(6):567-571
OBJECTIVE:
To investigate the mechanisms by which MecA gene expression leads to β-lactam resistance in methicillin-resistant Staphylococcus aureus (MRSA), and to study the resistance mechanism of MRSA at the molecular level.
METHODS:
A variety of molecular biological techniques were employed, including screening MRSA using cefoxitin paper disk method, extraction of MRSA mRNA, reverse transcription into cDNA, real-time fluorescence PCR for quantitation of MecA gene expression, and agar dilution method for assessment of minimum inhibitory concentrations in MRSA treated with cefoxitin, oxacillin, vancomycin, or linezolid.
RESULTS:
According to the level of resistance of MRSA to cefoxitin, 40 MRSA strains were divided into a low resistance group (n=12), a middle resistance group (n=15), and a high resistance group (n=13). The expression level of the MecA gene in the low resistance group, the middle resistance group, and the high resistance group was 58.87±30.30, 363.37±200.05, and 1257.72±446.63, respectively. MRSA resistance to cefoxitin and oxacillin was 100%; MRSA resistance to vancomycin or linezolid could not be detected. For all 40 MRSA strains the MIC90 for vancomycin was 2.0 μg/mL.
CONCLUSION
MecA gene expression levels may correlate with the MRSA level of resistance to cefoxitin within a certain range of concentration.
Anti-Bacterial Agents
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pharmacology
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Bacterial Proteins
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genetics
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metabolism
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Cefoxitin
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pharmacology
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Drug Resistance, Multiple, Bacterial
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Methicillin-Resistant Staphylococcus aureus
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drug effects
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genetics
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metabolism
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Microbial Sensitivity Tests
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methods
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Oxacillin
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pharmacology
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Penicillin-Binding Proteins
9.Risk factors for septic shock in patients with solid organ transplantation and complication of bacteremias.
Xuefei XIAO ; Qiquan WAN ; Qifa YE ; Ying MA ; Jiandang ZHOU
Journal of Central South University(Medical Sciences) 2012;37(10):1050-1053
OBJECTIVE:
To explore the risk factors for septic shock in patients with solid organ transplantation and complication of bacteremias.
METHODS:
Clinical data of 98 solid organ transplant cases with complication of bacteremias were retrospectively studied. All episodes of bacteremias met the CDC criteria. Six possible risk factors contributing to septic shock were evaluated by univariate analysis and multivariate logistic regression analysis.
RESULTS:
Among the 98 patients, 133 times of bacteremias have been reported and 39 patients developed septic shock. Among the 39 patients with septic shock, 43.5%, 38.5%, 15.4% and 2.6% of bacteremias were induced by multiple bacteria, gram-negative bacteria, gram-positive bacteria and fungi, respectively. The lung was the main source of bacteremias (41.8%), followed by intraabdominal/ biliary focus (24.5%). Risk factors for developing septic shock included the bacteremias happened in the 2nd to 8th week post transplant (P=0.014), polymicrobial etiology (P=0.001), intra-abdominal/ biliary focus (P=0.011), and liver transplant (P=0.002). Only bacteremias occurred in the 2nd to 8th week post transplant and polymicrobial etiology were significant risk factors by multivariate analysis.
CONCLUSION
Risk factors for developing septic shock in bacteremias after SOT are early-onset (the 2nd-8th week post transplant) and polymicrobial etiology.
Bacteremia
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complications
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Humans
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Multivariate Analysis
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Organ Transplantation
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adverse effects
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Retrospective Studies
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Risk Factors
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Shock, Septic
;
complications
10.Risk factors for bloodstream infections in liver or kidney transplantation recipients.
Qiquan WAN ; Xuefei XIAO ; Qifa YE ; Jiandang ZHOU
Journal of Central South University(Medical Sciences) 2012;37(9):924-927
OBJECTIVE:
To investigate the possible risk factors for death among liver or kidney recipients with bloodstream infections (BSIs).
METHODS:
A retrospective study of 138 episodes of bloodstream infections documented in 103 patients was conducted to assess potential risk factors for mortality. The risk factors were identified by logistic regression analysis.
RESULTS:
The mean age of the patients was 12-66 (42.3±12.7) years. The majority of infections were nosocomial (78.6%). The BSIs-related mortality rate was 39.8% (41/103). The following variables were identified as risk factors for BSIs-related mortality by univariate analysis: intraabdominal/ biliary focus (P=0.003), polymicrobial infection (P<0.001), liver transplant (P<0.001), platelet count <50000/mm3 (P<0.001), and septic shock (P<0.001). Platelet count < 50000/mm3 (P=0.002) and septic shock (P<0.001) showed significantly difference between the mortality group and the survival groups in the multivariate logistic regression analysis.
CONCLUSION
Decreased platelet count and septic shock are risk factors for increased
Adolescent
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Adult
;
Aged
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Bacteremia
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epidemiology
;
etiology
;
mortality
;
Cause of Death
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Child
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China
;
epidemiology
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Female
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Gram-Negative Bacterial Infections
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epidemiology
;
etiology
;
mortality
;
Humans
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Kidney Transplantation
;
adverse effects
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Liver Transplantation
;
adverse effects
;
Male
;
Middle Aged
;
Retrospective Studies
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Risk Factors
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Shock, Septic
;
epidemiology
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Thrombocytopenia
;
epidemiology
;
Young Adult