Objective To investigate the mechanism of resistance of clinical isolates of Pseudomonas aeruginosa to carbapenems.Methods Fifty-eight strains of imipenem-and meropenem-resistant Pseudomonas aeruginosa were isolated.Modified K-B technique was adopted in the susceptibility test by adding ?-lactamases inhibitors and efflux pumps inhibitors to M-H agar plates.The refined three-dimensional extract test was used to detect ?-lactamases.The genes of metallo-enzyme IMP,VIM,as well as outer membrane porin D2(OprD2) were analyzed with polymerase chain reaction.Results Among the 58 strains of carbapenems-resistant Pseudomonas aeruginosa,53 produced over-expressed active efflux and continuously produced large amont of AmpC enzyme,15 of which were accompanied by the loss of OprD2,and 1 of which were accompanied by extended spectrum ?-lactamases(ESBLs).Among the 5 strains which neither produced over-expressed active efflux nor ?-lactamases,only 1 was found with OprD2 gene deletion.Metallo-enzyme was not detected in any of the 58 strains.Conclusion The mechanism of resistance of Pseudomonas aeruginosa to carbapenems was mainly the production of the over-expressed active efflux combined with the continuous production of large amount of AmpC enzyme.Sixteen of the strains were accompanied by the loss of OprD2 gene.

Objective To investigate the technical charactenstics ot SYSMEX XS1000i 5-part differential automated hematological analyzer and its clinical applications.Methods 209 samples were analyzed with the analyzer of XS1000i and compared to the results from Beckman-Coulter LH750 analyzer.The main parameters from XS1000i,such as precision within-run,day to day precision and carryover contamination rates etc,were recorded respectively in 509 samples to compare the difference between the instrumental and optical examination.Results All variation coefficients of precision from XSI000i were within the manufacturer.The carryover contamination rates of WBC,RBC,Hb,HCT and PLT were 0.19%,0.93%,0,-0.88%,-0.76%,respectively.The parameters of XS1000i were correlated with the results of LH750 except basophil granulocyte.The correlation coefficients of WBC,RBC, HGB and PLT were 0.994 5,0.996 8,0.997 0 and 0.974 6 ,respectively.The sensitivity of warning flags in immature leukocytes was 100% and the specificity was 69.7%,the sensitivity of warning flags in atypical lymphocyte was 100% and the specificity was 66.7%.Especially in 3 leukocytopenia that was induced by chemotherapy in patients with leukemia who had only few immature cells existed in the peripheral blood,the parameters of XS1000i were positive,and correlated with the results of detection of minimal residual disease with flow cytometry.Conclusions The warning system of XSIO00i provides more valuable information for manual microscopic examination.If it is combined with flow cytometry,the advantages in detection of residual leukemic cell will be fully displayed.

Objective　To investigate the IL-6 signal transduction pathways and their regulation mechanism in a human myeloma cell line-U266. Methods　Electrophoretic mobility shift assay (EMSA) was used to detect the activation of the transcription factors (TFs)-STAT3 and NF-IL-6 by IL-6. Cells were treated with chemical agents or transfected with the expression plasmids for the two TFs or the anti-sense oligonucleotide for protein kinase involved in one IL-6 signal transduction pathway. The change of the activation state of another IL-6 signal transduction pathway was also exhibited by EMSA. Results　Two IL-6 signal transduction pathways (JAK/STAT and Ras/NF-IL-6) can be activated by IL-6 of different dose in U266 cells. When one of the two signal transduction pathways was up-regulated, the other one was down-regulated. Conclusion　There is an antagonistic effect between the activation of two IL-6 signal transduction pathways in U266 cells.

Objective To study the production of ?-lactamase in multidrug-resistant Pseudomonas aeruginosa and to guide the proper use of antibiotics in clinical practice. Methods The modified three-dimensional extract test was employed to detect ?-lactamase in 30 multidrug-resistant Pseudomonas aeruginosa strains screened from antimicrobial susceptibility test in our hospital,and isoelectric focusing electrophoresis was performed on the enzyme-producing strains. Results No metalloenzyme was detected in all the 30 strains.Twenty-six strains produced ?-lactamase,among which 25 continuously yielded large amount of AmpC enzyme and the other one both AmpC enzyme and extended-spectrum ?-lactamases(ESBLs).86.7% of multidrug-resistant Pseudomonas aeruginosa produced enzyme. ConclusionThe majority of the multidrug-resistant Pseudomonas aeruginosa in our hospital yielded large amount of AmpC enzyme in a continuous way.The modified three-dimensional extract test can eliminate some interference such as the decrease of outer membrane permeability and overexpression of efflux pump,facilitating the effective and accurate detection of ESBLs in Pseudomonas aeruginosa.

Objective To discuss the results and characteristics of surgical treatments through anterior or posterior approach for thoracolumbar burst fractures. Methods The retrospective review included 43 cases with an average age of 30.4 years from September, 1999 to November, 2004. The surgical approach was chosen according to conditions of the injury. 17 cases received an anterior approach operation. The Frankel scale was used for assessment of nerve function. 3 cases were rated as Grade A, 12 as Grade B, 19 as Grade C, and 9 as Grade D before surgery. Results The mean follow-up period was 36.7 months. There were no severe postoperative complications, such as deterioration of nerve function. All the cases showed notable improvement. Except in 3 cases of complete paraplegia, the improvement was 1.6 and 1.3 Frankel grades respectively for the anterior and posterior approach operations. Conclusions The anterior and posterior approaches are different in advantages and characteristics. The surgery through anterior approach provides more decompression and better maintenance of sagittal plane alignment.

[Objective]To investigate the diagnosis and treatment of lumbosacral nerve roots anomalies. [Method]Etiological factors,typing,diagnosis and treatment of lumbosacral nerve roots anomalies confirmed by operation were analyzed.Operative treatment included wide laminectomy(n=8),hemilaminectomy(n=8) and enlargement fenestration(n=9).[Result]The presenting symptoms of lumbosacral nerve roots anomalies often resulted from lumbar disc herniation or spinal canal stenosis.The typs of lumbosacral nerve roots anomalies included conjoined nerve roots(n=10),closely adjacent roots(n=8),thickening of nerve roots(n=2),caudal origin roots(n=2),division of nerve roots(n=1),double nerve roots(n=1),and anastomosis of nerve roots(n=1).The levels of nerve roots anomalies were L4 in 1,L5 in 14,and S1 in 10.Only 5 cases were diagnosed preoperatively by myelography,CT or MRI.The others were found at operation.All patients were followed up for more than 2 years.Postoperatively,the results were rated as excellent in 12,good in 8,and fair in 4.One patient had residual radiating pain in the lower lims and weakness in dorsiflexion of the foot. [Conclusion] Radicular symptoms of lumbosacral nerve roots anomalies are changeable.The preoperative diagnosis is difficult to establish by myelography,CT or MRI(axial and sagittal plane).It is necessary to heighten the sensitivity of diagnostic modalities.It may improve the surgical outcomes to expose sufficiently,to explore the nerve roots carefully and to decompress thoroughly.

Objective: To investigate which step of IL-6 signal transduction pathways in myeloma cells can be taken as the acting target of the antagonists for IL-6. Methods: EMSA and immunoprecipitation were used to detect the activation of transcription factors(TFs)-STAT3, NF-IL-6 and protein kinase ERK in a myeloma cell line-Sko-007 by IL-6. then anti-sense expression plasmids and anti-sense ODN for these signal moleculars were constructed and designed,the effects of these anti-sense nucleic acids on IL-6 signal transduction in Sko-007 cells were analyzed by the same methods. Results: IL-6 signal transduction could be antagonized by these anti-sense nucleic acids at different extent.Conclusion: TFs or protein kinases in IL-6 signal trareduction pathways can be taken as the target for antagonists design.

Objective: To explore the effects of peritoneal dialysis on acute renal insufifciency and on relevant blood indicators in children with congenital heart disease (CHD) after the operation.
Methods: A total of 48 CHD patients received direct open heart surgery by cardiopulmonary bypass and suffered from post-operative acute renal insufifciency in our hospital from 2011-12 to 2014-12 were retrospectively analyzed. The patients were divided into 2 groups: Peritoneal dialysis group and Routine medication group,n=24 in each group. The differences of renal function indexes, the blood levels of electrolyte and inlfammatory factors were compared between 2 groups.
Results: Compared with Routine medication group, the patients in Peritoneal dialysis group presented decreased serum critinine, BUN and urine β2-micro globulin, 24-hour protein level,P<0.05; decreased blood K+ level and increased blood levels of Ca2+, HCO-3P<0.05; decreased plasma levels of hs-CRP, TNF-α, IL-6,P<0.05. The cure rate and mortality in Peritoneal dialysis group were better than those in Control group,P<0.05. No long term complication related to peritoneal dialysis was found.
Conclusion: Peritoneal dialysis may improve the renal function in CHD patients with post-operative acute renal insufifciency and optimize the blood levels of electrolyte and inlfammatory factors.

Three compounds were isolated from solid culture of endophyte Myrothecium roridum IFB-E091 in Artemisia annua. Their structures were determined as (S)-(-)-N-[2-(3-hydroxy-2-oxo-2,3-dihydro-1H-indol-3-yl)-ethyl]-acetamide (1), N-(4-hydroxyphenethyl)acetamide (2) and asperfumoid (3), in which compound 1 was a new indole derivative. In cytotoxicity assay, the compound 1 had no obvious inhibition activity in human hepatoma cell line SMMC-7721 and human cervical carcinoma cell line HeLa.

Objective To investigate the correlation between deep vein thrombosis(DVT) and clinical laboratory tests in the regulation of hemostasis. Methods Endothelin-1 (ET-1), thrombomodulin (TM), P-selectin, prothrombin fragment _ 1+2 (F_ 1+2 ), thrombin-antithrombin complex (TAT), thrombus precursor protein (TpP) and D-Dimer (D-D) were measured in DVT patients (n=72) and normal individuals (n=20) with ELISA method. The sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and accuracy were evaluated for each of the items, and the area of the underlying receiver operating characteristic curve (AUC ROC ) was used to appraise diagnostic efficiency. Results Except ET-1, there were significant differences between the DVT group and normal control group in the other items. The AUC ROC of P-selectin, F_ 1+2 , TpP and D-D was bigger than that of ET-1, TM and TAT (P0.05). The TpP had the highest sensitivity, NPV and accuracy, and the D-D had the highest specificity and PPV. Conclusion The increase of D-D and TpP could reflect the occurrence of continuous coagulation and fibrolysis respectively. Thus the combination of measuring TpP and D-D could provide better laboratory evidence for the diagnosis of patients with DVT.