Combined Modality Therapy ; High-Frequency Ventilation ; Humans ; Liquid Ventilation ; Nitric Oxide ; therapeutic use ; Pulmonary Surfactants ; therapeutic use ; Respiration, Artificial ; Respiratory Insufficiency ; therapy

Objective To study the antibiotic resistance mediated by the mar mechanism in clinical isolated Escherichia coli. Methods To analyse the antibiotic resistance pattern and the out membrane protein spectrum of clinical isolated E. coli . The plasmid pNJR3 2 carrying the wild type gyr A gene was transferred into clinical multiple resistant strain LC 1. The resistant pattern and plasmid pattern of LC 1 before and after plasmid transferring were compared. The mar OR of clinical strain LC 1 was cloned and sequenced through PCR. The nucleotides of mar gene were compared with the wild type issued by GenBank. Results Of all the 49 clinical strains , six strains express Mrp5, a mar specific out membrane protein. No changes were detected on susceptibility to fluoroquinolone of clinical strain LC 1 after pNJR3 2 transferred suggesting that gyr A was not the main reason contributing to fluoroquinolone resistance. Sequence analysis showed three mutant spots in mar OR of clinical strain LC 1. Conclusion There does exist mar mechanism in clinical isolated Escherichia coli resistant to fluoroquinolone. The mutation in mar OR may contribute to the mar phenotype of LC 1.

Objective To study the Genotype of local clinical isolates of Enterobacteriaceae producing extended spectrum ? lactamases. Methods K B test, conjugative transfer test, plasmid profile analysis, PCR, PCR RFLP, and DNA sequencing were used to detect the phenotype and genotype of 33 isolates of Enterobacteriaceae producing ESBLs. Results Eighty five percent of 33 isolates was resistant to cefotaxime which was obviously higher than that to ceftazidime. blaCTX M ESBLs was detected in 28 isolates by PCR, blaTEM DNA in 24 isolates, and blaSHV DNA in 9 isolates. Mutation of E104K was only identified in one TEM ? lactamase produced by EC98A7 by PCR RFLP. No substitution of G238S occurred in 9 SHV ? lactamases. DNA sequencing and DNA alignment showed the blaCTX M DNA fragments from 4 clinical isolates of EC98A7,EB56,CFR78 and, KP9941 belonged to CTX M type 1, with highest identity to blaCTX M 3 or blaCTX M 12 respectively. Conclusions CTX M ESBLs is carried in 85% isolates of Enterobacteriaceae producing ESBLs in this city. Most of the isolates carry 2 or more ? lactamases. E. coli EC98A7 produces two ESBLs, a TEM ESBL and a CTX M ESBL.

Objective To investigate the correlation between BRAF V600E mutation and anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (MoAbs) therapeutic effects in metastatic colorectal cancer.
Methods Studies were included into meta-analysis to investigate the association between BRAF V600E mutation and clinical outcome in metastatic colorectal cancer patients treated with anti-EGFR MoAbs.
Results A total of 7 studies were included in this meta-analysis. The 7 studies included 1352 patients in total, sample sizes ranged from 67 to 493. Objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) were collected from included studies and were used to assess the strength of the relation. In patients with wild-type KRAS, the pooled odds ratio for ORR of mutant BRAF over wild-type BRAF was 0.27 (95%CI=0.10-0.70). BRAF mutation predicted a deterioration in PFS and OS in wild-type KRAS patients treated with anti-EGFR MoAbs (hazard ratio=2.78, 95% CI=1.62-4.76;hazard ratio=2.54, 95%CI=1.93-3.32).
Conclusion BRAF V600E mutation is related to lack of response and worse survival in wild-type KRAS metastatic colorectal cancer patients treated with anti-EGFR MoAbs.

Objective To investigate the amounts of endothelial progenitor cells(EPCs)in peripheral blood of patients with proliferative diabetic retinopathy(PDR).Methods Forty patients with PDR(PDR group),thirty patmnts with type 2 diabetes mellitus(DM)without DR(DM group),and twenty agematched normal subjects(control group)were enrolled in this study.Blood samples were treated bv repeated centrifugation and stained with monoclonal antibodies.At least 2 × 105 cells were analyzed bv flow cytometry.EPCs were identified by CD34 and CD133 antibody.The correlation between EPCs numbers and DR duration,glycosylated hemoglobin,serum lipids was analyzed.Results The number of EPCs in PDR,DM and control group were(49±12)、(35±11)、(90±25)cells/ml respectively,the difference was statistically significant(F=56.260,P=0.000).There was a positive correlation between EPCs numbers and DR duration(r=0.564,P＜0.05).However there was no correlation between EPCs numbers and glycosylated hemoglobin(r=-0.170,P>0.05)or triglyceride levels(r=0.261,P>0.05).Conclusions The number of EPCs in peripheral blood of PDR patients was decreased. EPCs might play an important role in the pathogenesis of PDR.

ObjectiveTo determine the allele frequency and genotypic distribution of plateletactivating factor acetylhydrolase (PAF-AH) gene polymorphism in the patients with sepsis. Methods Ala379Val,Val279Phe site genotypes were determined in patients (n=66) and healthy controls(n=68) by means of restriction fragment length polymorphism analysis of polymerase chain reaction products,DNA sequencing was used to detect the PCR product containing allele gene polymorphism.SPSS13.0 statistical software was use to analyze.Results All the samples by PCR-RFLP analysis of the PAF-AH gene in the Ala379Val site have three kinds of genotypes: in 66 cases of sepsis group there were 1 homozygous Val/Val type,19 heterozygous Val/Ala type,46 homozygous Ala/Ala type.In 68 cases of control group there were 2 Val/Val type,22 Val/Ala type,44 Ala/Ala type.The Ala379Val allele frequency and genotypic distribution in the patients with sepsis was not significantly different from those in the healthy controls.No statistically significant difference was observed between the survival group and the death group ( P＞0.05 ).PAFAH gene of Va1279Phe polymorphism could have three kinds of genotypes.All 66 patients in the sepsis group were the homozygous Val/Val type.Control group 68 cases,only one case was homozygous Phe/Phe type,and the others were homozygous Val/Val type,not found heterozygous Val/Phe type.The Val279Phe genotypic distribution and allele gene frequency in the patients with sepsis was not significantly different from those in the healthy controls; no statistically significant difference was observed no statistically significant difference was observed between the survival group and the death group ( P＞0.05 ).ConclusionNo associations were found between PAF-AH gene Ala379Val and Val279Phe polymorphisms and sepsis susceptibility,prognosis and severity.

OBJECTIVE To investigate the repressor SmeT and other sequences of efflux pump SmeDEF in the clinic isolates of Stenotrophomonas maltophilia to involve in antibiotic resistance. METHODS The mRNA level of smeD examined the resistance profile of the clinical strains to antimicrobials was by agar dilution and their reaction to pump inhibitor was investigated by RT-PCR,and the smeD-smeT fragment was amplified by PCR,and then sequenced.Adding poly(A) to 3′ end of RNA,applying 3′RACE,nested PCR,then sequence-analysis. RESULTS The amino acid sequences of the forepart of SmeT were conservative in all the 7 strains.In antibiotic-resistant strains with positive reaction to pump inhibitor,the intergenic sequences of smeD-smeT were different from those in sensitive ones.The variations in(-165 to-82)nt of smeT and several nucleic acids before the start codon of smeT,possibly involved in antimicrobial resistance.All isolates didn′t have Leu166Gln mutation within the SmeT protein of D457R,which was reported possibly associated with antibiotic resistance.The resistant strains with efflux positively inhibited had Asp218Glu substitution,different from the negatively-inhibited ones. CONCLUSIONS The expression level of SmeDEF is related with the antibiotic resistance of S.maltophilia.The possible resistance mechanism includes the variations in the intergenic smeD-smeT and/or smeT codon sequence.

Objective To evaluate the MRA by measuring the diameter of the stenosis artery and the contralateral normal vertebral artery with unilateral stenosis. Methods Seventeen-six patients were divided into normal group and vertebral arterial type of cervical spondylosis group.Among 26 vertebral arterial type of cervical spondylosis cases,13 cases appeared as vertebral arterial type with unilateral stenosis of ≤1.6 mm in diameter .Statistics assessment of MRA in stenosis and contralateral artery was engaged. Results The unilateral artery stenosis diameter measured

BackgroundHypoxia-inducible factor-1 α (HIF-1α) specific double-stranded RNA ( dsRNA ) mediated by liposome inhibit reinal neovascularization in mice at dose-dependent manner. ObjectiveThe present study was to investigate the inhibitory effect of dsRNA targeting HIF-1α on retinal neovascularization in mice.MethodsModels of oxygen-induced retinal neovascularization were set up in C57BL/6J mouse through exposure of postnatal day 7 ( P7 ) to (75±3) ％ oxygen for 5 days.Fluorescein conjugated Dextran angiography of retinal vascular was performed to identify the retinal neovascularization.The 8 mice of the normal group were raised in the room air.Fifty-one P7 mice exposed to(75±3)％ oxygen for 5 days and then returned to the room air and assigned to control group ( 3 mice),empty vector group( 3 mice) and gene therapy group (45 mice),and the latter were medially divided to 9 groups randomly according to dose-ratio ( liposomes ∶ plasmid).The pSilencer 2.1-U6 hygro was injected in the model mice of empty vector group,and different dose-ratios of pSilencer2.1-U6 hygro-HIF-1α dsRNA were injected respectively in the model mice of various gene therapy groups.Fluorescein conjugated Dextran angiography of retinal vascular was performed to observe the morphology of new blood vessels,and retinal slides were prepared to score the numbers of nuclei extending beyond the inner limiting membrane( ILM ),and expression of vascular endothelial growth factor(VEGF) was detected in the retina by immunohistochemistry.Results The retinal blood vessels of the normal group formed a fined radial branching pattern.The retinal vascular patterns in the control group and the empty vector group were characterized by decreased central perfusion in both the superficial and the deep layers.The abundant vessels were distorted and irregular in the control group and empty vector group,and the obstructed capillary and lots of neovascular tufts were seen.The retinal neovascularization and non-perfusion distraction in the every gene therapy group were reduced markedly with the most severe appearance in 1 ∶ 1 ( liposomes ∶ plasmid) dose-ratio group.Few vascular endothelial cell nucleus extending beyond the ILM were found in the normal group;while a large number of vascular endothelial cell nucleus were showed in the control group and empty vector group with the occurring rate 100％.Statistically,no significant difference was seen in the number of nuclei extending beyond the ILM between the control group and the empty vector group(11.57±5.85 vs 11.53±6.15),however,that in 1∶1 (liposomes∶plasmid) group was reduced markedly ( 2.17 ± 4.23 ) ( P ＜ 0.01 ).Immunohistochemistry revealed that VEGF was faintly expressed in the normal group but strongly expressed in the control group and the gene therapy group.VEGF expressions of various gene therapy groups were weaker than ones of the control group and the empty vector group.ConclusionsRetinal neovascularization can be efficiently inhibited by intravitreal injection of the pSilencer2.1-U6 hygro-HIF-1α dsRNA mediated by liposome.Proportion of 1 ∶ 1 (liposomes ∶ plasmid)has a maximized efficiency.