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OBJECTIVES@#Currently, it is difficult to assess the expression status of hormone receptor (HR) in breast malignant tumors with human epidermal growth factor receptor 2 (HER-2)-positive in the early preoperative stage, and it is difficult to predict whether it is non-invasively. This study aims to explore the value of MRI on the different HR expression status (HR+/HR-) in HER-2 positive breast cancer.@*METHODS@#Thirty patients with HR+ HER-2-positive breast cancer (HR+ group) and 23 patients with HR-HER-2-positive breast cancer (HR- group) from the First Hospital of Hunan University of Traditional Chinese Medicine between January 7, 2015 and November 26, 2021 were selected as subjects, and all the patients were examined by MRI and all were confirmed by surgery or pathological biopsy puncture. The immunohistochemical staining results were used as the gold standard to analyze the basic clinical conditions, peri-lesion conditions and MRI sign characteristics in the 2 groups.@*RESULTS@#There were all significant differences in terms of mass margins, internal reinforcement features, and apparent diffusion coefficient (ADC) values between the HR+ group and the HR- group (all P<0.05). The logistic multivariate regression model showed that: when the lesion presented as a mass-type breast cancer on MRI, the internal enhancement features of the lesion were an independent predictor for differentiation in the 2 types of breast cancer [odds ratio (OR)=5.95, 95% CI: 1.223 to 28.951, P<0.05], and the mass margin (OR=0.386, 95% CI: 0.137 to 1.082, P>0.05) and ADC value (OR=0.234, 95% CI: 0.001 to 105.293, P>0.05) were not the independent predictors in distinguishing the 2 types of breast cancer.@*CONCLUSIONS@#Multiparametric MRI has good diagnostic value for HR expression status in HER-2-positive breast cancer. Combined logistic regression analysis to construct a predictive model may be helpful to the identical diagnosis.
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Humans , Female , Breast Neoplasms/surgery , Magnetic Resonance Imaging/methods , Diffusion Magnetic Resonance Imaging/methods , Breast , Magnetic Resonance Spectroscopy , Retrospective StudiesABSTRACT
@#To optimize the process of hydrogenation reduction in the synthesis of apremilast (APST), 3-nitrophthalic anhydride (4) and (S)-1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl) ethanamine-(S)-2-acetamido-4-methylpentanoate (7) were used as starting materials to synthesize (S)-2-(1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl)-4-nitroisoindoline-1,3-dione (8) by amination.Then compound 8 was reduced to (S)-4-amino-2-(1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl) ethyl) isoindoline-1,3-dione (9) with ammonium formate as hydrogen source and palladium hydroxide as catalyst.Finally, apremilast was obtained by the acetylation reaction with acetic anhydride.The structure of the products were verified by optical rotation, 1H NMR, 13C NMR, MS and elemental analysis.And the total yield of three steps was increased to 67.0%.The improved reduction process can avoid the special reaction of hydrogenation and pressurization, and reduce the safety risk and production costs with high commercial value.
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OBJECTIVE：To explore t he mechanism of Xinmaikang improving atherosclerosis （AS）in rabbits. METHODS ：A total of 50 male Zealand rabbits were randomly divided into sham operation group ，model group ，simvastatin group [positive control ， 2.60 mg/（kg·d）] and Xinmaikang low-dose and high-dose groups [ 0.21，0.84 g/（kg·d）]，with 10 rabbits in each group. Rabbits in sham operation group were fed with ordinary diet ，and only femoral artery was separated and ligated ，and abdominal aortic endothelium was not strained ；the other groups were given high-fat diet and received abdominal aortic intimal balloon injury to induce AS model. Ten weeks after operation ，sham operation group and model group were given intragastric administration of normal saline ，and administration groups were given corresponding drug solution intragastrically （normal saline as solvent ）with the volume of 100 mL，once a day ，for consecutive 12 weeks. After last administration ，the pathological changes of abdominal aorta and inner wall in rabbits were observed in each group. The serum contents of triglyceride （TG），total cholesterol （TC），low density lipoprotein cholesterol （LDL-C），high density lipoprotein cholesterol （HDL-C），interleukin-6（IL-6）and IL- 1β were detected，and the contents and protein expression of Toll-like receptor 4（TLR4）and nuclear factor-κB p65（NF-κB p65）in abdominal aortic tissue were determined. RESULTS ：Compared with sham operation group ，the intima of abdominal aorta in model group was rich in lipids ，the thickness of vessel wall and plaque area were increased obviously ，and there was obvious vascular endothelial injury. The contents of TG ，TC，LDL-C，IL-6 and IL- 1β in serum，the contents and protein expression of TLR 4 and NF-κB p65 in abdominal aorta tissue were significantly increased ，while the content of HDL-C was decreased significantly （P＜0.05 or P＜ 0.01）. Compared with model group ，the lesion of rabbit abdominal aorta were alleviated ，and no obvious damage was found on the inner wall. The contents of TG ，TC，LDL-C，IL-6，IL-1β of Xinmaikang high-dose group and simvastatin group as well as the content of NF-κB p65 and protein expression of TLR4 and cnd- NF-κB p65 were improved significantly （P＜0.05 or P＜0.01）. CONCLUSIONS：Xinmaikang can improve AS in rabbits ， and its mechanism may be assicated with inhibiting the expression of TLR 4，NF-κB p65 and inhibiting inflammatory response.
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Cryptococcal meningitis is a common and refractory central nervous system infection,with high rates of mortality and disability.The experts of the Society of Infectious Diseases of Chinese Medical Association have reached this consensus after a thorough discussion.Based on the current situation of cryptococcal meningitis in China,the management of cryptococcal meningitis includes 6 aspects:introduction,microorganism identification,clinical manifestations and diagnosis,principles of antifungal therapy,treatment of refractory and recurrent meningitis,treatment of intracranial hypertension.There is not a separate consensus on human immunodeficiency virus (HIV) infection in patients with cryptococcal meningitis.This article focuses on different antifungal regimens and reducing intracranial pressure by reference to Infectious Disease Society of America (IDSA) guidelines.The importance of early diagnosis,combined long-term antifungal therapy,control of intracranial hypertension are emphasized.
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Angelica dahurica is diaphoretic, commonly used in the treatment of cold, wet, and itchy rubella nasosinusitis. Studies have shown that the effective components of Angelica dahurica can be used in the treatment of malignant tumors. This paper summarizes the related literature home and abroad recently, and regards the effective components of Angelica dahurica as a major role in treatment of tumor by inhibiting tumor cell proliferation, promoting apoptosis, inhibiting tumor metastasis, inhibiting platelet aggregation, enhancing immunity, and anti-tumor drug resistance. Meanwhile, the paper finds the shortcomings of the present researches, and hopes to provide reference for the future experiment and clinical research.
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Objective@#To examine the proliferating cell nuclear antigen (PCNA) expression in submandibular gland of diabetic mice and to investigate the influence of fibroblast growth factor 1 (FGF-1) on PCNA expression and its possible mechanism.@*Methods@#Sixteen db/db diabetic male mice were randomly divided into diabetic group and diabetic-FGF-1 group (n=8). Eight age-matched db/m mice served as a control group. After FGF-1 was administered intraperitoneally to diabetic-FGF-1 group continuously for 16 weeks, blood glucose and body weight of each mouse in the three groups were detected at 0, 4, 8, 12, 16 weeks. Then the flow rate of saliva in three groups was compared at 0, 8, 16 weeks. At 16 week, bilateral submandibular glands were resected. Then HE staining was performed to observe the histological morphology of submandibular gland and PCNA expression was examined by immunohistochemical staining.@*Results@#Four weeks after administration, the blood glucose in diabetic-FGF-1 group decreased markedly, close to the control group (P>0.05). Weight loss in diabetic-FGF-1 group was noticeable at 8 weeks after administration, but still higher than that in the control group (P<0.05). The flow rate of saliva in diabetic-FGF-1 group increased gradually after administration, which was higher at 8, 16 weeks ([260.1±43.3], [308.5±34.0] mg·min-1·kg-1) respectively than that in the diabetic group at the same time point ([181.8±37.5], [194.9±49.8] mg·min-1·kg-1) (P<0.05). Compared with the control group, submandibular glands in diabetic group significantly atrophied and the glandular atrophy in diabetic-FGF-1 group was alleviated. The submandibular gland index in the control group, diabetic group and diabetic-FGF-1 group were (7.45±0.63), (2.23±0.26), (3.97±0.15) mg/g, respectively (P<0.05). HE staining showed that the histological morphology of submandibular gland in diabetic-FGF-1 group was clearer, and acinar and ductal atrophy were less significant than diabetic group. Immunohistochemistry showed that the rate of PCNA-positive cells in the control group, diabetic group and diabetic-FGF-1 group were (45.23±7.78)%, (11.50±1.69)%, (36.98±6.53)% respectively (P<0.05).@*Conclusions@#FGF-1 can up-regulate the expression of PCNA in submandibular gland of diabetic mice. This effect may be one of the important mechanisms of FGF-1 reversing the structural atrophy and dysfunction of submandibular gland caused by diabetes mellitus.
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Objective To investigate the clinical effect of pedicle screw internal fixation with different surgical approach in the treatment of thoracolumbar vertebral fractures. Methods Fifty?three cases with thoracolumbar vertebral fracture without nerve injury were selected as our subjects,who were hospitalized in the Central Hospital of Chaoyang from January 2008 to December 2013. They were randomly divided into observation group(27 cases) and control group(26 cases). The patients in the observation group were treated with pedicle screw internal fixation with Wiltse paraspinal approach and the patients in the control group were treated with pedicle screw internal fixation with traditional posterior open approach. The duration of operation,intraoperative blood loss,volume of drainage and length of hospital stay of all patients were recorded and the ratio of anterior vertebral body height to normal height before and after operation was compared between the two groups. Visual analog scores( VAS) for pain severity and Cobb’ s angle of the vertebrae was compared between the two groups 1 year after operation. Results The duration of operation and length of hospital stay of patients in both groups had no statistically significant differences ( P>0. 05 ) . The intraoperative blood loss and volume of drainage in observation group were less than that in control group respectively((146. 3±25. 1) ml vs. (240. 2±28. 7) ml, (73.1±15.3) ml vs. (150.5±20.1) ml;P=0.034,0.023).The ratio of anterior vertebral body height to normal height 1 week after operation was higher than that before operation in the observation group ( ( 93. 1 ±5.1)% vs. (70.3±8.6)%,P=0.048) and in the control group((93.0±6.0)% vs. (71.8±9.8)%,P=0. 049),the difference between two group had no statistically significant(P>0. 05). The Cobb′s angle of the vertebrae 1 year after operation was less than that before operation in the observation group((10. 10±4. 00)° vs. (19. 10±7. 81)°,P=0. 045) and in the control group ((9. 97±3. 78)° vs. (18. 87±6. 90)°,P=0. 045),the difference between two group had no statistically significant(P>0. 05). The VAS for pain severity 1 year after operation was less than that before operation in the observation group(1. 1±0. 5 vs. 6. 0±0. 9,P=0. 023) and in the control group ( 1. 7 ± 0. 6 vs. 5. 9 ± 0. 7, P= 0. 038 ) , the difference between two group had statistically significant( P=0. 046) . Conclusion Pedicle screw internal fixation with Wiltse paraspinal approach in the treatment of thoracolumbar vertebral fractures without nerve injury has advantages with traditional posterior open approach in less trauma, less bleeding, rapid recovery and reduces the incidence of postoperative lumbar pain. The treatment has a good clinical effect and is worthy of clinical application.
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This paper reports a case of melanotic neuroectodermal tumor of infancy (MNTI)arising in the maxilla of a 3-month-old male infant.The treatment included surgical excision of the lesion with safe margin,curettage of the maxilla and removal of associated developing tooth bud.Microscopically,it proved to be a dual tumor with small,neuroblastic-like cells and larger epithelial cells.Immunohistochemical staining demonstrated epitheloid cells HMB45(+),EMA(+),CK(+);neuroblast-like cells NSE(+),GFAP(+),S-100(+),but both cells Vim(+),CD45(-),Myogenin(-).The 18-mouth follow-up showed no recurrence or metastasis.The related literature was re-viewed.
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<p><b>OBJECTIVE</b>To investigate the preventive effect of low-intensity ultrasound on osteoradionecrosis of jaws (ORNJ).</p><p><b>METHODS</b>Twenty-five canines were randomly divided into experimental group (n=20) and control group (n=5). The canines in experimental group received radiation exposure, and then were randomly subdivided into group A (n=10) and group B (n=10). Control group did not undergo radiotherapy. One month after radiotherapy, the fourth mandibular premolars of all animals were extracted. Group B was immediately treated by low-intensity ultrasound for twenty days, group A and control group did not receive any treatment. Two months after tooth extraction, the formation of ORNJ was determined and the occurrence rate of ORNJ was compared between group A and B. The microstructure of the mandible and changes in microvascular density in group A and B were evaluated and compared with those of control group.</p><p><b>RESULTS</b>All animals in group B and group A developed ORNJ after prophylactic ultrasound was applied for twenty days. Although the imaging examination of bony density of group A and B were lower than normal animals in control group, bone density in group B was significantly better than group A. Micro-CT showed that the trabecular bone volume fraction, trabecular thickness, bone surface/bone volume and trabecular number in group B were respectively (0.187±0.029)%, (0.160±0.039) µm, (12.536±2.558)/mm, (1.227±0.192)/mm, which were all greater than group A [(0.103±0.014)%, (0.069±0.013) µm, (5.598±0.731)/mm, (0.522±0.064)/mm)] (P<0.05).</p><p><b>CONCLUSIONS</b>Although the preventive application of low intensity ultrasound can not prevent the formation of ORNJ, but can significantly improve the symptoms of ORNJ.</p>
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Animals , Dogs , Bone Density , Radiation Effects , Jaw Diseases , Mandible , Osteoradionecrosis , Radiation Injuries, Experimental , Random Allocation , Tooth Extraction , Ultrasonic Therapy , Methods , X-Ray MicrotomographyABSTRACT
<p><b>OBJECTIVE</b>To investigate the influence of zoledronic acid on vascular endothelial cells.</p><p><b>METHODS</b>The influence of zoledronic acid on proliferation, migration and adhesion of vascular endothelial cells were tested with 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), cell migration assay and cell adhesion assay. The results of each experimental group were compared with the control group and the data statistically analyzed.</p><p><b>RESULTS</b>In a concentration of 0-0.5 mmol/L, the absorbance value decreased from 0.09 to 0.34 as the drug concentration increased. Scratch test showed that the change of width of scratch before and after 24 hours in control, low, medium and high concentration groups were (38.7 ± 0.42), (35.8 ± 4.17), (19.9 ± 0.57) mm (P < 0.001), (12.5 ± 3.89) mm (P < 0.05). Adhesion test showed that the absorbance value in control, low, medium and high concentration groups were 1.14 ± 0.18, 0.95 ± 0.13, 0.81 ± 0.11 (P < 0.01), 0.67 ± 0.19 (P < 0.001). Comparisons between control and experimental groups were analyzed by t-test and P values < 0.05 were considered statistically significant.</p><p><b>CONCLUSIONS</b>Zoledronic acid inhibits the proliferation, migration and adhesion of vascular endothelial cells.</p>
Subject(s)
Cell Adhesion , Physiology , Cell Movement , Physiology , Cell Proliferation , Diphosphonates , Pharmacokinetics , Pharmacology , Endothelial Cells , Cell Biology , Imidazoles , Pharmacokinetics , PharmacologyABSTRACT
Objective To investigate the antibiotic resistance of extended-spectrum-β-1actamases (ESBLs)-producing Escherichia coli (E.coli) and Klebsiella pneumoniae (K.pneumoniae) isolates and the risk factors of bloodstream infections caused by these strains.Methods Clinical data of 131 patients with E.coli or K.pneumoniae-induced bloodstream infections admitted in the Second Affiliated Hospital of Zhejiang Chinese Medical University during September 2009 and June 2014 were retrospectively analyzed.Species identification and antimicrobial susceptibility test were performed by Vitek 2 system,and ESBLs production was tested by standard disk diffusion method.Logistic regression analysis was performed to identify the risk factors of bloodstream infections induced by ESBLs-producing strains.Results Among 131 patients,65 were infected with ESBLs-producing strains,and 66 were infected with non-ESBLs-producing strains.The resistance rates of ESBLs-producing strains were above 50％ for penicillin,aztreonam and third/fourth generation cephalosporins,which were significantly higher than those of non-ESBLs producing strains.The resistance rates of ESBLs-producing E.coli and K.pneumoniae to carbapenems and piperacillin/tazobactam were 0-2.0％,2.3％ and 0-14.3％,26.7％,respectively.The univariate analysis revealed that patients with exposure to cephalosporins in recent 3 months (x2 =18.322,P ＜ 0.01),prior infection with ESBLs-producing strains (x2=14.610,P＜0.01),indwelling catheter in recent 3 months (x2 =13.016,P ＜ 0.01),history of hospitalization in recent 3 months (x2 =11.269,P ＜ 0.01),exposure to quinolones in recent 3 months (x2 =10.638,P ＜ 0.01),nosocomial infection (x2 =8.205,P ＜ 0.01),history of indwelling deep venous catheter or percutaneous central catheter in recent 3 months (x2 =4.817,P ＜ 0.05) and exposure to glucocorticoid hormone in recent 3 months (x2 =4.265,P ＜ 0.05) were associated with infection of ESBLs-producing strains.Multivariate Logistic regression analysis revealed that exposure to quinolones in recent 3 months (OR =6.851,P ＜ 0.01),prior infection with ESBLs-producing strains (OR =6.344,P ＜ 0.01),exposure to cephalosporins in recent 3 months (OR =3.719,P ＜ 0.01),and indwelling catheter in recent 3 months (OR =3.180,P ＜ 0.05) were independent risk factors for ESBLs-producing E.coli or K.pneumoniae infection.Conclusions ESBLs-producing E.coli or K.pneumoniae isolates are highly resistant to most antibiotics,and multidrug-resistance is common.Carbapenems were still the most effective antibiotics against ESBLs-producing E.coli or K.pneumoniae infection.Rational use of cephalosporins and quinolones,strictly following aseptic technique in operation,strict use of indications for indwelling catheterization,and completely eradicating ESBLs-producing strains in previous infections may be helpful in reducing bloodstream infections by ESBLs-producing E.coli or K.pneumoniae.
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Objective To explore the influence of treatment duration on the prognosis of Cryptococcus neoformans meningitis (CNM). Methods The clinical data of 30 patients with CNM were retrospectively analyzed. The time of Cryptococcus neoformans culture in cerebrospinal fluid turned to be negative were compared between patients with and without amphotericin B (AmB)endoneurilemma injection to determine whether endoneurilemma injection would make any difference on prognosis of CNM. Statistic analysis was performed by t test. Results The time of Cryptococcus neoformans culture in cerebrospinal fluid turned to be negative was (22. 73 ± 10. 00) days in 11patients with AmB endoneurilemma injection compared to (18. 92±7. 26) days in 13 patients without endoneurilemma injection. The difference was not statistically significant (t = 0. 172,P>0. 05). The effective rate was 45. 8% after 2-week anti Cryptococcus neoformans treatment, which increased to 100.0% after 6-week treatment. However, the curative rate at week 6 of treatment was 0. All ten patients who finished the treatment (three to four months' treatment) were acquired effective.Conclusion Treatment with standard dosage and adequate duration is crucial in improving the prognosis of Cryptococcus neoformans meningitis.
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Objective To investigate the resistant mechanism of carbapenem-resistant Escherichia coli and its relationship with endogenous infection. Methods Two carbapenem-resistant Escherichia coli strains were isolated from blood and stool of a same patient, respectively. The minimal inhibition concentrations (MIC) of the two isolates against imipenem and meropenem were determined by E-test. The susceptibility against other antimicrobial agents were done by disc diffusion method. Isoelectric focusing electrophoresis (IEF), polymerase chain reaction (PCR) amplification,cloning and sequencing, conjugation, Southern blotting were carried out to analyze the encoding gene of β-lactamases. Homology analysis of the two strains was done by pulsed field gel electrophoresis (PFGE). Results MIC against imipenem and meropenem of the two strains were both≥32 mg/L.Both strains produced KPC-2 (pI 6.7) and SHV-12 (pI 8.2) β-lactamases. blaKPC2gene was located on a 54 kb transferable plasmid. PFGE showed that the two Escherichia coli strains were derived from the same clone. Conclusions The resistance and enzyme digestion map of chromosome DNA of the two Escherichia coli strains are coincident. The Escherichia coli septicemia of this patient is probably an endogenous infection caused by the immigration of Escherichia coli from the gut.
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Objective To investigate the resistance of Pseudomonas aeruginosa and genotyping of the main β-lactamases in China. Methods A total of 645 Pseudomonas aeruginosa isolates were collected from 28 hospitals in 16 cities in China from July 2006 to July 2007. The susceptibilities to 11 kinds of antimicrobial agents were detected by agar dilution or Kirby-Bauer disk diffusion method. The genotypes of β-lactamases including TEM, SHV, CTX-M and OXA of all the strains were detected by polymerase chain reaction (PCR) and sequence analysis. Results The resistance rates of 645 Pseudomonas aeruginosa isolates to antimicrobial agents were high, except those to amikacin and meropenem were lower than 30 %. Two hundred and seventy-five (42. 64 % ) strains were carbapenem and (or) meropenem-nonsusceptible Pseudomonas aeruginosa. Three hundred and sixty-eight (57.05 %) strains were multidrug-resistant Pseudomonas aeruginosa and 20 (3. 10%) strains were pandrug-resistant. The genotyping results of β-lactamases were as follows: 51 stains produced OXA-10 group β-lactamases, 37 were CARB type, 36 were TEM, 35 were PER, 11 were CTX-M, 9 were VEB, 5 were SHV, 24 were metallo-β-lactamases positive and 1 was GES. None of genotypes of plasmidmediated AmpC enzyme and other carbapenemases were detected. CTX-M-13, CTX-M-14,CTX-M-15, CTX-M-3 of extended spetrum β-lactamese were detected in Pseudomonas aeruginosa.Conclusions The situation of Pseudomonas aeruginosa resistances is severe in China. OXA-10 and PSE-1 are the most common genotypes of β-lactamases. The β-lactamases genotyping is different between carbapenem-nonsusceptible and carbapenem-susceptible strains.
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Objective To investigate the resistance of carbapenems,the production of metallobeta-lactamases(MBLs)and homology analysis of Psendomonas aeruginosa in China.Methods A total of 654 Pseudomonas aeruginosa isolates were collected from 28 hospitals in 16 difierent regions during the period from July 2006 to July 2007 as part of the Nosocomial Pathogen Resistance Surveillance(NPRS).MICs of imipenem and meropenem were determined by agar dilutiom PFGE was used to analyze the molecular epidemiology of carbapenem-resistant strains.MBLs were detected by Etest and PCR among carbapenem-non-sensitive strains.The transcription levels of MBLs were determined by real-time reverse transcriptase(RT)-PCR.Results Of the 645 Pseudomonas aeruginosa strains,245(37.5%)were resistant to imipenem and 183(28.0%)were resistant to meropenem.A total of 275 carbapenemnonsusceptible strains and 259 carbapenem-resistant strains were chosen for further study. Among the carbapenem-nonsusecptible strains,8.73%(24/275)of the strains carrried MBLs genes hy PCR,but only 6.55%(18/275)of the strains were detected as MBls-producers bv MBL Etest. The MBLs relative expression levels of the 6 MBL genotype-positive but phenotype-negative strains were significantly lower than those of the other 18 MBL genotype-and phenotype-positive strains(P＜0.05).The 259 carbapenemresistant Pseudomonas aeruginosa strains were divided into 89 clones by PFGE.The 24 MBL genotypepositive strains collected from 6 cities were divided into 9 clones by PFGE.Conclusions The carbapenems resistance of Pseudomonas aeruginosa is severe in China.Clonal dissemination of Pseudomonas aeruginosa has not been detected throughout China.MBLs are not the major carbapenems resistance mechanism in Pseudomonas aeruginosa.
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Objective To characterize the prevalence of plasmid-mediated quinolone resistance determinants qnrA in extended-spectrum β-lactamase(ESBL)-producing Escherichia coli and Klebsiella pneumonia.Methods PCR was used to amplify qnrA gene in ESBL-rpoducing isolates(including 263isolates of Escherichia coli and 99 isolates of Klebsiella pneumonia).Conjugation experiments and southern blot hybridization were employed to definitude the location of the genes in ZJ96 isolate of Klebsiella pneumonia which had positive qnrA and CTX-M genes.Shot gun sequencing was performed for analyzing the complete nucleotide sequence of pKP96,a plasmid containing qnrA and CTX-M-24 genes in ZJ96 isolate.Results qnrA was detected in 5 out of 263(1.9%)Escherichia coli isolates and 8 out of 99(8.1%)Klebsiella pneumonia isolates.pKP96,a conjugative plasmid including qnrA gene and CTX-M-24 gene presented in ZJ96 isolate.The sequence of the plasmid pKP96 displayed the qnrA,CTX-M-24,aac(6')-Ib-cr,tetA and int Ⅰ 1 genes.Conclusion The plasmid-mediated genes,such as qnrA and CTX-M,may facilitate the prevalence of multi-drug resistant strains.
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<p><b>OBJECTIVE</b>To investigate the status of the drug resistance and the ampC gene expression of Enterobacter cloacae.</p><p><b>METHODS</b>Disk diffusion tests were made for detecting the susceptibility of antimicrobial agents against Enterobacter cloacae. AmpC gene was amplified by polymerase chain reaction (PCR) and verified by DNA sequencing. AmpC gene expression was analyzed according to antimicrobial agent sensitive phenotype.</p><p><b>RESULTS</b>The sensitivity rates of 144 strains to imipenam, cefepime and cefoperazone/sulbactam were 98.61%, 65.97% and 63.89%, respectively. The sensitivity rates of 144 strains to other antimicrobial agents were lower. Among the 144 strains 120 were found to be positive by PCR for ampC. The PCR product showed high homology to the GenBank ampC sequence. Stably derepressed strains, hyperinducible strains and unexpressing or lower level expressing strains accounted for 30.0% (36/120), 37.5% (45/120), and 32.5% (39/120), respectively. Fifty-six out of 120 strains (46.67%) also produced extended spectrum beta-lactamases (ESBLs). The hyperinducible strains were highly sensitive to all the antimicrobial agents except amoxicillin/clavulanic acid and cefuroxime, while the stably derepressed strains were only sensitive to imipenam and cefepime. However, sensitivity to cefepime decreased if the strains also produced ESBLs.</p><p><b>CONCLUSIONS</b>The drug resistant status of Enterobacter cloacae is severe. Clearing out the expressive status of ampC gene will be helpful in selection of antimicrobial agents in the treatment of clinical infection.</p>