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Objective:To compare the quality of Astragali Radix at different harvest time; To revise the content determination indexes of Astragali Radix in Chinese Pharmacopoeia. Methods:An Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm, 5 μm) was used for the determination of saponins with acetonitrile-water solution as mobile phase in a gradient mode. The drift tube temperature of ELSD was 60 ℃; the pressure was 30 psi; the gain was 800 ℃; the flow rate was 1.0 ml/min; the column temperature was 30 ℃; the injection volume was 20 μl; the acetonitrile-0.2% formic acid solution was used as mobile phase for the determination of flavonoids in a gradient mode; the flow rate was 1.0 ml/min; the detection wavelength was 260 nm; the column temperature was 30 ℃; the 10 μl was injected. The limited range as an indicator for determining Astragali Radix content was determined by investigating the extraction method and extraction time of Astragaloside Ⅰ and detecting the content of Astragaloside Ⅰ in 12 batches of Astragali Radix from different origins. The moisture, total ash, and water-soluble extracts in Astragali Radix were determined according to the drying method, total ash determination method, and cold soaking method in the four parts of Chinese Pharmacopoeia (2020 edition), respectively. Results:The content of total saponins in Astragali Radix harvested in spring and autumn in different origins was not significantly different, but the content of total flavonoids was significantly different. Except for H11, the content of Astragaloside Ⅰ in the other batches of Astragali Radix was ≥ 0.05%, so the content limit of Astragaloside Ⅰ was proposed to be≥0.05%. The results of moisture, total ash and water-soluble extracts in the 12 batches of Astragali Radix all meet the requirements in the Chinese Pharmacopoeia. Conclusions:Astragali Radix harvested in autumn is with higher content of active components and better quality. At the same time, this study can provide a reference that the new version of Chinese Pharmacopoeia can revise the Astragaloside Ⅳ in the content determination index of Astragali Radix to Astragaloside Ⅰ .
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OBJECTIVE：To establish a method for the determination of 8 glycosides（astragaloside Ⅰ，Ⅱ，Ⅲ，Ⅳ and calycosin glucopyranoside ，2′-hydroxy-3′，4′-dimethoxy-isoflavan-glucoside and 9，10-dimethoxy-pterocarpan-glucoside） and 4 aglycones（calycosin，formononetin，7，2′-dihydroxy-3′，4′-dimethoxy-isoflavan and 3-hydroxy-9，10-dimethoxy-pterocarpan） in Astragalus membranaceus ，and to investigate the effects of different processing temperatures on the contents of above 12 components. METHODS ：The contents of 12 components in A. membranaceus and samples processed under different temperatures（120，140，160，180，200 ℃）were determined by UPLC-MS/MS. The determination was performed on ACQUITY UPLC HSS T 3 column with mobile phase consisted of 0.1 mol/L formic acid water solution -0.1 mol/L formic acid acetonitrile solution （gradient elution ）at the flow rate of 0.5 mL/min. The column temperature was 30 ℃. The detection wavel ength was 260 nm，and sample size was 2 μL. Electrospray ion source（ESI）was used under positive ion mode （ESI+）. The mass scanning range was mass ratio （m/z）of 50-1 500，with capillary voltage of 2 000 V and ion source temperature of 100 ℃. The desolvation temperature was 400 ℃；flow rate of atomizing gas （N2） was 40 L/h，and that of desolvation was 800 L/h；collision energy （CE）was 20-30 V；data acquisition rate was 0.5 s/scan. RESULTS：The linear range of astragaloside Ⅰ，astragaloside Ⅱ，astragaloside Ⅲ，astragaloside Ⅳ，calycosin-glucopyranoside， calycosin，ononin，formononetin，2′-hydroxy-3′，4′-dimethoxy-isoflavan-glucoside，7，2′-dihydroxy-3′，4′-dimethoxy-isoflavan，9， 10-dimethoxy-pterocarpan-glucoside and 3-hydroxy-9，10-dimethoxy-pterocarpan were 0.001 16-0.232 0，0.000 276-0.055 2， 0.000 22-0.044 0，0.000 225-0.045 0，0.000 734-0.587 0，0.001 17-0.234 0，0.000 742- 0.148 0，0.001 30-0.260，0.003 98-0.795 0， 0.000 476-0.476 0，0.001 89-0.378 0，0.000 336-0.336 0 μg（all R2≥0.999 2），respectively. The limits of detection were 6.2×10－6， 4.8×10－6，3.8×10－6，3.4×10－6，5.8×10－6，4.8×10－6，4.2×10－6，3.2×10－6，5.8×10－6，2.6×10－6，4.2×10－6，6.4×10－6 μg，respectively. The limits of quantitation were 12.6×10－6，16.2×10－6，14.4×10－6，14.8×10－6，18.8×10－6，16.4×10－6，15.4×10－6，10.8×10－6，20.2×10－6， 12.4×10－6，14.6×10－6，23.4×10－6 μg，respectively. RSDs of precision ，stability（24 h）and repetition tests were all lower than 3.0％（n＝6）. The average recoveries were 99.1％，100.2％，98.7％，101.9％，98.6％，102.1％，99.2％，100.3％，98.7％， 99.2％，99.3％ and 100.8％，with the RSDs of 1.9％，2.2％，2.4％，1.8％，2.1％，1.7％，2.3％，1.9％，2.4％，1.8％，2.2％ and 1.9％（n＝6），respectively. The results showed that the contents of astragaloside Ⅰ，Ⅱ and Ⅲ decreased gradually with the increase of processing temperature ；the content of astragaloside Ⅳ increased gradually with the increase of temperature. The content of flavonoid glycosides ，such as calycosin glucopyranoside ，ononin，2′-hydroxy-3′，4′-dimethoxy-isoflavan-glucoside and 9， 10-dimethoxy-pterocarpan-glucoside decreased with the increase of temperature ；the corresponding aglycone components as flavonoid glycosides ，formononetin，3-hydroxy-9，10-dimethoxy- pterocarpan increased firstly and then decreased with the increase ； the content of 7，2′-dihydroxy-3′，4′- dimethoxy-isoflavan decreased with the increase of temperature. CONCLUSIONS ：Established UPLC-MS/MS method can be used for determination of 12 components in A. membranaceus . After processed under different temperature，the contents of glycosides decreased in general ，while the contents of aglycones increased in general.
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Objective: To detect eight highly related driver genes in non-small cell lung cancer (NSCLC), and to analyze the relationship between gene variations and clinical-pathological features. Methods: We collected 212 NSCLC samples from Tianjin Medical University Cancer Institute and Hospital, and sequenced eight genes which are EGFR, KRAS, BRAF, ALK, MET, ERBB2, ROS1 and RET. Results: EGFR gene variation rate was as high as 52.8%, followed by KRAS (8.5%), ALK (8.0%), ERBB2 (6.1%), MET (3.8%), BRAF (1.4%), RET (0.9%) and ROS1 (0.9%) in eight detecting genes, at least one driver gene variant was detected in 75% samples, and driver gene variant showed strong mutual exclusion. The most common EGFR mutations were 19 exon deletion and L858R mutation, and the mutation of EGFR T790M was accompanied by the above two mutations. The proportion of non-EGFR T790M mutations in patients with exon 19 dele-tion was lower than that of L858R mutations (P=0.04). There were 15.2% patients with EGFR mutation accompanied by EGFR amplifica-tion, and the proportion of patients with EGFR mutation frequency greater than 40% with EGFR amplification was higher than that without EGFR amplification (P<0.01). Women, non-smoking, patients with adenocarcinoma were prone to carry EGFR especially EGFR sensitive mutations (P<0.01). Patients with lung adenocarcinoma (P=0.013), late clinical stage (P=0.048), and lymph node metastasis (P=0.027) had a higher proportion of EGFR amplification. The incidence of KRAS mutation was higher in men, left lung cancer and smoking patients (P=0.009, P=0.048, P=0.037). Patients with non-KRAS mutations, ALK fusions were younger (P=0.005, P=0.031), and with KRAS mutations were older (P=0.055). Conclusions: Next-generation sequencing (NGS) can simultaneously detect eight highly re-lated driver genes in NSCLC patients to provide evidence for clinicians. NGS based on detection of multiple genes provides more possi- bilities for individualized diagnosis and treatment of NSCLC.
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Objective:To study the effects of IL-8 on the polarization of monocytes and the effects of IL-8-induced tumor-associated macrophages(TAMs)on the invasion and metastasis of hepatocellular carcinoma(HCC).Methods:After exogenous IL-8 stimulation of THP-1 cells for 72h,the percentages of M1 and M2 TAMs were examined.RT-PCR and Western blot assays were used to study epitheli-al-mesenchymal transition(EMT),and wound-healing and transwell assays were preformed to study the invasion potential of HCC cells after co-culturing with TAMs and HCC cell lines in vitro.Lastly,100 cases of HCC tissue samples were used to validate the correlation among TAM numbers,IL-8,and EMT features of HCC cells via immunohistochemistry(IHC)staining methods.Results:Exogenous IL-8 induced significant M2 polarization of TAMs in THP-1 cells.TAMs further promoted EMT in HCC and enhanced the invasion potential of HCC in vitro.Finally,significant positive correlations among the numbers of TAMs,IL-8 expression,and N-cadherin expression were identified in primary HCC tissue samples(r=0.22,r=0.20,P<0.05).Conclusions:IL-8 locally attracted and activated TAMs,and promot-ed M2 polarization of TAMs,which further promoted the EMT and invasion potential of HCC cells both in vitro and in vivo.
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Objective The aim of this study was to investigate and analyze the etiology, seizure type and anti-epileptic drugs (AEDs) utilization of in-patients with epilepsy Methods The study included 5563 cases in-patients with epilepsy. The etiology and seizure type and the date of type, quantity of AEDs in-patient department were collected and their usage frequency were analyzed statistically. Results The most common etiology of epilepsy was traumatic brain injury(13.64%), followed by hippocampal sclerosis (11.52%), stroke (5.24%), nervous system infection (4.98%), perinatal injury ( 5 . 28 % ) and undefined etiology ( 40 . 80 % ) . The most common seizure type was partial seizures (45.43% ). The AEDs of carbamazepine and valproate were the most common used drugs in the clinical and their average usage frequency were 36.88% and 30.80%, respectively. The newer AEDs of Lamotrigine and Levetiracetam were used more frequently. The use of Lamotrigine increased from 16.16% to 28.44% and the Levetiracetam from 0.61% to 20.87% whereas the use of Oxcarbazepine and Topiramate remained a stable level of 15.07% and 9.42%. Conclusion The etiology of epilepsy is complicated and the seizure type of epilepsy was diverse. Among a great variety of anti-epileptic drugs, the newanti-epileptic drugs are being increasingly used.
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Objective:To highlight the developmental process of 3D cell culture technology system, which is more suitable for isolating and identifying lung cancer stem-like cells than 2D cell culture technology system, and to explore the application of 3D cell cultures in the evaluation of proliferation, apoptosis, invasion, and drug resistance of lung cancer. Methods:Cells (104/well) from the human lung adenocarcinoma cell lines A549 and RPMI 1640 were cultured in complete medium containing 10%fetal bovine serum. Cell suspension was cultured in a BME basal medium. A growth curve was drawn after 7 d of culture. The stem-like cell was identified through a mammosphere culture, drug resistance and invasion assay, and flow cytometry. Data of A549 cells cultured in 3D and 2D tra-ditional cell culture technologies were compared. Results: Cells from the 3D cell culture had higher tumor formation rates [(20.75 ± 0.85) d vs. (60.25 ± 1.49) d, P<0.01)] and tumor sphere formation (28.50%± 1.17%vs. 8.67%± 0.80%, P<0.01) than those from the 2D cell culture. Moreover, cells from 3D cell culture were more invasive and resistant to therapy (58.17%± 2.19%vs. 41.70%±5.81%in 48 h, P<0.01;33.27%±5.76%vs. 27.30%±4.25%in 72 h, P<0.01). Phenotype experimental results demonstrated that the CD44 and CD326 cells were double-positive, whereas the CD24 cell was negative. Conclusion:The proportion of stem-like cells in A549 cell line after 3D cell culture significantly increased compared with 2D cell culture. The 3D cell culture can promote the proliferation of lung cancer stem cells.
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BACKGROUND:Although several prosthetic methods, such as artificial denture and dental implants, are clinical therapies to tooth loss, they are thought to have safety and usage time issues. With the development of biological and biomaterial sciences, recently, tooth tissue engineering has attracted more and more attention. OBJECTIVE:To reflect advances and problems of tissue engineering technologies for promotion of tooth regeneration. METHODS:Using the keywords of“tissue engineering, tooth regeneration”in English and Chinese, PubMed and CNKI databases from 2007 to 2013 were retrieved. A total of 65 literatures addressing tooth regeneration and tissue engineering were col ected, including 25 Chinese articles and 40 English articles. Published early, repetitive, and similar researches were excluded. Final y, 48 articles were included. RESULTS AND CONCLUSION:The combination of stem cells and suitable scaffolds is widely used in tooth regeneration today, and growth factors or bone marrow which can produce promote tooth regeneration are added as wel , which has achieved partial or whole tooth regeneration. But there are apparent deficiencies in studies which focus on mechanisms behind tooth regeneration.
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Objective:This work aims determine the expression of the neurotensin (NTS) gene in hepatocellular carcinoma (HCC) subgrouping using immunohistochemical staining (IHC) as well as to evaluate the correlation between the activation of NTS/IL-8 pathway in HCC and inflammatory response in microenvironment and epithelial mesenchymal transition (EMT) in cancer and in the prognosis of patients. Methods:Tumor tissues and corresponding adjacent normal tissue were collected from 64 cases of HCC patients. The expression levels of NTS protein and multiple inflammation and EMT-related proteins, including IL-8, VEGF, MMP9, CD68, E-Cadherin,β-Catenin, and Vimentin, were examined in 64 cases of paraffin-embedded HCC tissues using the immunohistochemistry (IHC) staining method. The clinical outcome and overall survival (OS) among 64 cases of HCC patients were compared. Results:We found that the frequency of NTS-expressing tissues among all HCC samples was 17.19%(11/64). Significantly increased IL-8 protein was confirmed in 90.91%of NTS+HCC samples and was positively correlated with the levels of NTS protein in cancer tissues (P=0.036), which implied the dysfunctional activation of NTS/IL-8 pathway in HCC. The levels of VEGF and MMP9 were significantly correlated with the co-expression of NTS and IL-8 in HCC. Evident features of EMT, including decreased membrane expression of E-Cadherin and increased accumulation of cytoplasmicβ-Catemin and Vimentin, were found in NTS+IL-8+samples. The co-expression of NTS and IL-8 in cancer was significantly correlated with the clinical outcomes of patients, as the mortality rate of NTS+IL-8+HCC patients is 2.5-fold higher than that of others after surgery (P=0.022).Accordingly, the OS of NTS+IL-8+HCC patients significantly decreased (24.65±4.45 m vs. 75.79±16.32 m, P=0.013), and these patients are at a higher risk of death at an expected hazard ratio (HR) of 3.457. Conclusion:The NTS/IL-8 pathway is dysfunctionally activated in a subgroup of HCC samples. Highly expressed NTS is associated with increased inflammatory response in microenvironment, enhanced EMT in cancer, and worse prognosis in HCC patients.
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Objective To investigate antimicrobial resistance among Streptococcus pneumoniae clinically isolated from 14 teaching hospitals located at different areas in China in 2005-2008 and to give logical guidance for clinical empirical therapy.Methods A total of 1 317 non-repetitive S.pneumoniae isolates in 14 teaching hospitals from 2005-2008 were collected and sent to the central lab for reidentification and susceptibility testing, including 271 isolates collected in 2005, 391 isolates collected in 2006, 363 isolates collected in 2007 and 292 isolates collected in 2008. Most of the isolates were from community-acquired respiratory tract infections, which were isolated from outpatient or emergency department patients with respiratory tract infections or those patients with respiratory tract infections within ≤48 hours hospitalization.The districts where the organisms were isolated include North China, Northeast China, South China, Central and Northwest China and East China.The patients included adults, teenagers and children.The minimum inhibitory concentrations (MICs) or inhibitory zone diameter of 17 antimicrobial agents were determined by Etest method, agar dilution method or disk diffusion method.WHONET5.5 software was used to analyze susceptibility rate, intermediate rate, resistance rate, MIC50 and MIC90.Results Linezolid (100%) and fluoroquinolones (95.2%-99.7%) showed excellent activities against S.pneumoniae.Among β-lactams, amoxicillin-clavulanic acid remained high activities (73.8%-92.1%),followed by penicillin, ceftriaxone and cefepime with year-over-year decrease in activities.The activities of three second-generation cephalosporins were low (36.3%-38.4% in 2008).The activities of erythromycin, azithromycin, clindamycin, trimethoprim/sulfamethoxazole and tetracycline against S.pneumoniae were poor and decreased year over year.The incidence of penicillin non-susceptible S.pneumoniae (PNSP) was increasing especially for PISP (from 4.4% in 2005 to 20.2% in 2008).The incidence of PNSP in North China was low (6.0%), while this value were high in central China and East China (30.1% and 38.7%, separately).The incidence of PNSP in adults (15.7%) was obviously lower than that in children(≤5 years:33.0%) and teenagers (6-17 years:38.2%).Conclusions linezolid and fluoroquinolones showed excellent in vitro activity against S.pneumoniae, followed by penicillin and cephalosporins with year-over-year decrease of activity. Clinicians should pay more attention when using those antimicrobial agents with poor activity against S.pneumoniae, which include macrolides, clindamycin, trimethoprim/sulfamethoxazole and tetracycline.
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Objective To evaluate the influences of susceptibility interpretation of Escherichia coli,Klebsiella pneumonia and Proteus mirabilis in China mainland according to the old and new ceftazidime,cefotaxime and ceftriaxone breakpoints in CLSI M100-S20 and CLSI M100-S19. Methods First, We analyzed the antibacterial susceptibility results of the three bacteria by agar dilution method in the SEANIR surveillance item, which were collected from 15 national hospitals between the year of 2005 and 2007 and excluded the AmpC enzyme positive isolates according to the PGR-DNA sequencing method and/or the antibacterial susceptibility phenotype. ESBL phenotype was confirmed by the CLSI phenotypic confirmatory test. Antibacterial susceptibility of the total 2733 Escherichia coli, Klebsiella pneumonia, Proteus mirabilis isolates was retrospectively analyzed by WHONET 5. 4 software according to the breakpoints of the CLSI M100-S19 (S19) and CLSI M100-S20 (S20). Second, 207 isolates of Peking Union Medical College Hospital with the results of both agar dilution method and disk diffusion method were performed by recurrent analysis. Then we observed the inter-method agreement through the scatter diagram according to the breakpoints of S19 and S20. Results First, as to the ESBL positive Escherichia coli, Klebsiella pneumonia and Proteus mirabili.s, the resistant rate of cefotaxime increased from 65.2% , 55.5%, 14. 6% under S19 (64 μg/ml) to 99. 7%, 96. 2% , 93. 8% under S20 (4 μg/ml). The susceptibility rates decreased from 6. 0%, 11.5%, 33.3% under S19 (8 μg/ml) to 0%, 0. 2%, 0% under S20 ( 1 μg/ml). Ceftriaxone had the same trend as cefotaxime. Though ceftazidime was more active than cefotaxime and ceftriaxone, as to the ESBL positive Escherichia coli and Klebsiella pneumonia, the resistant rates slightly increased from 30. 3%,43. 2% under S19 (32 μg/ml) to42.0%, 56. 0% under S20 (16 μg/ml). The susceptibility rates slightly decreased from 58. 1%, 44. 1% under S19 (8 μg/ml) to 44. 7%, 28.0% under S20 (4 μg/ml). Second,as to the ESBL negative Escherichia coli, Klebsiella pneumonia and Proteus mirabilis, all the susceptibility rates of ceftazidime, cefotaxime and ceftriaxone were between 99. 2%-100. 0%, the resistant rate were between 0%-0. 4%. Third, the S20 MIC breakpoints had a good correspondence with the ESBL phenotype.Fourth, according to the recurrent analysis of MIC testing and disk dilution method, r value was 0. 67,0. 79, 0. 77 for ceftazidime, cefotaxime and ceftriaxone, respectively, and all P value were under 0. 01. The intermethod rates of S19 and S20 were both acceptable. Conclusions If the cefotaxime and ceftriaxone S20 new breakpoints were used, the concordance of antibacterial susceptibility results and ESBL phenotype would increase greatly. The clinician could select proper antibiotics according to the antibacterial susceptibility results and clinical symptoms. It is no longer necessary to edit results for cephalosporins, aztreonam, or penicillins from susceptible to resistant. However, until laboratories implement the new interpretive criteria,ESBL testing should be performed as described in Supplemental Table 2A-S1. The relationship between the new breakpoints of ceftazidime and clinical outcomes need to be further evaluated.
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OBJECTIVE To study the distribution of pathogens and their antibiotic resistance in systemic lupus erythematosus(SLE)patients with gram-negative bacterial infections,for guiding the rational use of antibiotics therapy.METHODS The identification was analyzed by ATB Expression automatic microbiology analytical instrument system.The bacterial susceptibility test was done by Kirby-Bauer agar diffusion method.RESULTS Among 346 patients included,112(32.4%)had bacterial infections.A total of 181 pathogens strains had been isolated.Among 181 isolates,Escherichia coli,Pseudomonas aeruginosa,Klebsiella pneumoniae,Acinetobacter baumannii,Proteus mirabilis,and Enterobacter cloacae were the main pathogens.The ESBLs producing rates in E.coli and K.pneumoniae were 27.5% and 28.1%.Piperacillin/tazobactam and cefepime had less activity against A.baumannii and low resistant to other Gram-negative bacilli(0-46.2% and 13.0-33.3%).Meropenem,imipenem and cefoperazone/sulbactam showed greater activity against Gram-negative bacilli,their resistant rates were 0-17.1%,0-22.9% and 0-38.5%,respectively.CONCLUSIONS The clinical features of SLE patients with bacterial infections are lack of specificity.The data will be useful for reasonably choosing antimicrobial agents in the treatment of SLE patients with bacterial infections.
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Objective To identify the most common fungal pathogens and their antifungal drug resistance in autoimmune disease (AD) patients with fungal infection , for guiding the rational use of antifungal therapy. Methods The identification were analyzed by ATB Expression automatic microbiology analytical instrument system. The antifungal susceptibility test was done by ATB FUNGUS strip. Results Of 428 patients studied,36(8.4%) had fungal infections. The most commonly infective sites were lower respiratory tract(53.5%),urinary tract(20.9%), intestinal tract(11.6%). A total of 43 fungi strains were isolated, the most common fungi were Candida albicans (65.1%), Candida glabrata (11.6%), Candida tropicalis (7.0%),and Candida parapsilosis (4.7%).Resistance rates of Candida albicans against ketoconazole, miconazole and econazole were 35. 7% , 46.4% and 32.1% , while resistance rates to fluconazole, amphotericin B, nystain and flucytosine were much lower, being 0, 14.3% , 14.3% and 7.1% . The resistance rates of other fungi were similar to Candida albicans. Conclusion The main pathogens causing fungal infection in patients with AD is Candida albicans. It should as early as possible process the clinical antifungal therapy under the result of antifungal susceptibility test and supportive measure.
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OBJECTIVE To investigate in vitro activities of 12 antimicrobial agents including cefmetazole against extended-spectrum beta-lactamases-producing Escherichia coli(528 strains),Klebsiella pneumoniae(311 strains) and Proteus mirabilis(15 strains).METHODS They all collected from 15 teaching hospitals in China during 2005 and 2006 and included in the study.The levels of minimal inhibitory concentration(MIC) of 12 antimicrobial agents were determined by agar dilution method.WHONET 5.4 Software was used to analyze the data.RESULTS Against ESBLs-producing E.coli and ESBLs-producing K.pneumoniae,carbapenems were the most active antimicrobial agents(all 100.0% susceptible),followed by cephamycins(80.1-97.3%).Piperacillin/tazobactam(78.5-95.1%)showed a higher activity than cefoperazone/sulbactam(44.1-56.2%).The susceptible rate to ceftazidime against ESBLs-producing E.coli was remarkably higher than the other three cephalosporins,however the differences did not happen to ESBL-producing K.pneumoniae obviously.The susceptible rate to cefuroxime was below 1.6%.ESBLs-producing K.pneumoniae showed high sensitivity to carbapenems,cephamycins and ?-lactam/lactamase inhibitor combinations(all 100% susceptible),however the susceptible rates to cephalosporins were relatively lower.CONCLUSIONS Carbapenems and cephamycins remain the relatively high activity against ESBLs-producing Enterobacteriaceae.
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OBJECTIVE To investigate the tendency of bacterial distribution and resistance of hospitial infections,and to provide the reference for the clinical treatment and infection control in hospital.METHODS Bacteria isolated from patients in our hospital from Jan 2004 to Dec 2005 were identified by ATB expression,and bacterial susceptibility tests were performed on strains using Kirby-Bauer method.RESULTS A total of 3066 pathogens strains were isolated,among them 927 strains were Gram-positive cocci(30.2%).The most common pathogens of them were Staphylococcus.Meticillin resistant strains of Staphylococcus aureus and coagulase negative Staphylococcus(CNS) accounted for 69.0% and 77.6%,respectively.In our data,no vancomycin resistant S.aureus were isolated.There were 2134 strains of Gram-negative bacilli(69.6%),the most common pathogens of them were Pseudomonas aeruginosa,Escherichia coli,Klebsiella pneumoniae,Acinetobacter baumannii and Enterobacter cloacae.The ESBLs producing strains of E.coli and K.pneumoniae accounted for 30.1% and 40.1%,respectively.The highest susceptible to Gram-negative bacilli was carbapenem,then were cefoperazone/sulbactam,piperacillin /tazobactam and cefepime.Mainly pathogenic bacteria were multi-resistant to some antibiotics.CONCLUSIONS Drug resistance of the nosocomial infection bacteria is a serious problem.It's important and urgent to carry out surveillance of bacterial resistance for appropriate using of antibiotics and effective controlling nosocomial infections.
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OBJECTIVE To evaluate the antibacterial activities of cefoperazone combined with sulbactam against Gram negative bacteria,and compare with other antimicrobial agents.METHODS The antibacterial activities of 10 frequently used antibiotics against 1 670 strains of clinical isolated Gram negative bacteria were studied by using agar dilution methods according to the NCCLS 2002.RESULTS The results showed imipenem was the most active tested against Enterobacteriaceae such as Escherichia coli and Klebsiella pneumoniae,followed by cefoperazone-(sulbactam),which had similar activities as imipenem against the non-fermentative strains such as Pseudononas aeruginosa,and Acinetobacter spp,but cefoperazone-(sulbactam) had higher susceptibility to imipenem-(resistant) Stenotrophomonas maltophilia.CONCLUSIONS Cefoperazone-sulbactam has good and broad spectrum(antibacterial) activities especially against Gram negative(bacteria,) and is expected to have a bright prospect in the treatment of severe hospital infections induced by Gram negative bacteria.
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OBJECTIVE To study the existence of the ?-lactamase gene produced by multidrug-resistant Pseudomonas aeruginosa isolated from respiratory tract. METHODS Antimicrobial susceptibility was tested by K-B method. A modified three-dimensional test was used to detect the ?-lactamase phenotypes. The genotypes were analyzed by PCR amplification and product sequencing. RESULTS ?-Lactamases were detected in 29 out of the 46 isolates. Twenty-one isolates produced AmpC ?-lactamase,two of them harboring CARB-3 gene. Two isolates produced ESBLs harbored TEM gene. Six isolates produced other type of ?-lactamases. Four out of 6 harbored CARB-3 gene and three IMP gene. The oprD2 gene was deleted in 34 isolates. CONCLUSIONS Chromosomal-mediated AmpC ?-lactamase is the major ?-lactamases produced by multidrug-resistant P. aeruginosa and CARB-3 is second. Lack oprD2 gene is popular.