Objective To investigate the physiological state of L. pneumophila in biofilm. Methods Genes previously identified as good markers for the transmissive and replicative phases of the L. pneumophila life cycle during growth in Acanthamoeba castellanii were examined for their expression fold change in the sessile cells as compared to planktonic cells using real-time RT PCR. Results Mature L. pneumophila biofilms were formed at 37t in 75 cm2 cell culture treated flasks for 18 days. The ratio of gene (mip, flaA and fliA) expression in post-exponential cells compared to exponential cells is 0. 53, 4. 45 and 3. 67. The exponential phase cultures display replicative traits and post-exponential bacteria express transmissive factors. The ratio of gene (mip, flaA and fliA) expression in sessile cells compared to exponential cells is 4.42, 5.24 and 16.21, while the sessile cells compared to exponential cells is 8.39, 1. 18 and 4. 43, respectively. Conclusion The violence gene expression of L pneumophila in biofilm is unique.

OBJECTIVE To compare the difference of Pseudomonas aeruginosa(PAE) biofilms formation in different conditions including incubated time,temperature,attaching materials,and flowing speed.METHODS PAE biofilms were established in a chemostat-coupled MRD and detected with the method of viable bacteria counting.The number of CFU/disc was measured in different culture time(8h,24h or 72h),different temperature(23℃ or 37℃),different adherent materials(glass or silicone),different flow velocities(30ml/h or 90ml/h) and different culture media(M63 medium,M-H croth or LB broth).RESULTS Keeping the other conditions invariable,the log10CFU/disc of viable bacteria in 8h,24h or 72h biofilms were 4.01?0.26,4.59?0.49 or 5.20?0.47,respectively(P

Objectives: In this study,we evaluated the influence of different nutritional support routes and nutrients on the intestinal barrier function and bacterial translocation in rats with gut I/R injury. Methods: Sixty male Sprague Dawley rats were made ischemic by clamping the superior mesenteric artery for 30 minutes and were divided randomly into four groups of fifteen animals each,i.e.standard parenteral nutrition (PN),gln enriched TPN (G PN),common enteral nutrition (EN),and enteral immunonutrient (IEN) groups. All the rats received isocaloric nutrition support for seven days.Rats were killed after 7 days'nutrition support.Spleen,liver,mesenteric lymph nodes (MLN),and blood samples were collected for bacterial culture. Endotoxin levels in plasma were also measured.The permeability of intestine mucosa was assayed by D lactate level in plasma.The small intestine was removed for studies.Mucosal thickness,villous height,crypt depth and villous surface area were determined.The gut immune barrier function was evaluated by the immunohistochemical staining method. Results: Atrophy occurred in small intestinal mucosa in PN group.The mucosal thickness,villous height,crypt depth and villous surface area were decreased significantly in PN group compared with other groups ( P

Objective To evaluate the value of glycogen phosphorylase isoenzyme BB (GPBB) in the diagnosis of early acute myocardial infarction (AMI). Methods The plasma levels of GPBB were mea-sured by sandwich ELISA in 115 patients with suspected AMI at admission within 6 hours after onset of chest pain and 55 normal healthy subjects. The plasma concent of cardiac troponin-Ⅰ (cTnI), creatine kinase-MB (CK-MB) and myoglobin (MYO) was assayed at the same time by using corpuscle chemiluminescence. The patients were classified retrospectively into AMI group (n = 45) , unstable angina pectoris (UAP) group (n =40) , stable angina pectoris (SAP) group (n = 13) and non-cardiac chest pain (NCCP) group (n =17).The diagnostic validity was evaluated in terms of sensitivity and specificity. Results The diagnostic sensitivity of GPBB for AMI was 64.29 % within 3 hours and 88.89 % within 6 hours after onset of chest pain,which is significantly higher than that of cTnI (28.57 %, 60.00 %) and CK-MB (21.43 %, 64.44 % ). There was no significant difference in specificity among the four markers. The diagnostic accuracy of GPBB within 3hours and 6 hours (80.77 %, 89.57% ) was significantly higher than that of cTnI (61.54%, 81.74% ),CK-MB (50.00%, 75.65%) and MYO (73.08% ,73.91%). Conclusions GPBB seems to be a sensitive and specific biochemical cardiac marker for AMI in the early stage. Its diagnostic accuracy is higher than that of cTnI, CK-MB, MYO.

Objective To observe the effect of Ceftazidime on the early and mature Pseudomonas aeruginosa biofilm bacteria. Method The early and mature PA biofilm were formed through the chemostat combined Robbins device. Then 64 ?g/ml Ceftazidime was applied to the early and mature PA biofilm bacteria for 24 hours respectively. Scanning electronic microscope(SEM) was used to observe the effect of Ceftazidime on early and mature biofilm. The difference between the viable bacteria in early and mature biofilm was analyzed by statistical method. Result 24 hours after Ceftazidime was added, Pseudomonas aeruginosa in early biofilm was killed on the whole while there were still numbers of bacteria in mature biofilm. Statistical analysis demonstrates a great variance in viable counts. Conclusion Pseudomonas aeruginosa in mature biofilm is more tolerant to antibiotics than that in early biofilm.

Objective The purpose of this study was to compare and develop the method for identification of Non-tuberculous Mycobacteria (NTM) using matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS),and evaluate the feasibility,accuracy and repeatability of MALDI-TOF MS to discriminate NTM.Methods Fifteen clinical strains were collected from January to March in 2012 and 68 environmental strains were retrospectively collected from 2011 to 2012.A protocol for sample pre-treatment and protein extraction was developed and utilized it to identify clinical and environmental isolates.The results from 16 s rRNA sequencing were served as control.Results Method A was more effective in protein extraction.Although all the three methods got the same species result,a total of 83 strains belonging to 10 distinct species grown in Middle brook 7H10 media were analyzed.All members of the NTM were identified accurately at the genus level and 80.7％ (67/83) of strains could be identified at the species level.Six strains were identified at the complex level.81.9％ (68/83) of NTM got high spectral scores.The identification of cultured colony could be completed in 1.5 hours.And it had good reproducibility.Conclusion MALDI-TOF MS can be used as a rapid and accurate method for identification of Mycobacteria in clinical microbiology laboratories,implying its good application prospects.

Objective To compare the changes of plasma lipid indexes and coronary artery atherosclerotic plaque in TaqI B genotypes in CHD patients with impaired glucose tolerance (IGT) before and after statin therapy. Methods A total of 196 CHD with IGT and 160 controls were included. The changes of plasma lipid indexes and coronary artery atherosclerotic plaque in TaqI B genotypes were analyzed before and after Rosovastatin therapy. Sequenom Mass ARRAY platform was used to detect the CETP TaqI B SNPs. Results The genotype frequency of the B1B1, B1B2 and B2B2 in CHD with IGT group was 35.7%, 48.0% and 16.3% respectively, while in control group was 31.3%, 53.1% and 15.6% respectively. HDL-C, PA and MLA levels increased after Rosuvastatin therapy, while LDL-C, TG, TCH, Lpa, PA, EEMA and PB levels decreased. Conclusions CETP gene polymorphisms TaqI B would have association with the effects of Rosuvastatin therapy in the CHD with IGT.

Objective To explore the difference of gene expression profiling between normal basilar arteries and basilar arteries of cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH) in rabbits. Methods cDNA chip of normal basilar arteries and basilar arteries of CVS after SAH in rabbits were downloaded from GEO database. The chip was analyzed and screened by Bioconductor software, and function enrichment and pathway analysis of the differentially expressed genes were analyzed by Cytoscape software. Then 6 adult male Japanese rabbits were used, and randomly divided into normal control group (n=3) and SAH model group (n=3). Rabbit SAH models were established by cisterna secondary-blood-injection method. RNA data of normal basilar artery specimens on the 0 day and basilar artery specimens after SAH on the 5-day were used to validate the parts of differentially expressed genes by qRT-PCR. Results A total of 4356 differentially expressed genes were found in normal basilar arteries and basilar arteries of CVS after SAH in rabbits. Among them, 920 genes were considered to be significant with P-value<0.05, such as GRIK1, MYH13, ZNF45, SAA3, RLN1, MSR1 and others. Function enrichment analysis indicated that the differentially expressed genes were involved in regulation of Ca2+transmembrane transporter activity, negative regulation of ion transmembrane transport, regulation of potassium ion transport, positive regulation of JAK-STAT signaling cascades and other biological processes. Pathway analysis showed that calcium signaling pathway, cGMP-PKG signaling pathway, HIF-1 signaling pathway, PI3K-Akt signaling pathway and other signaling pathways maybe related with the differentially expressed genes. qRT-PCR verification showed that the expression of MSR1 in SAH model group was consistent with that of the chip result. Conclusion The gene expressions of basilar arteries of CVS after SAH in rabbits are significantly different, and MSR1 gene can be used as a potential target for studying the pathological mechanism of CVS.

An impeller plays a significant role in the non-invasive ventilator. This paper shows a model of impeller for noninvasive ventilator established with the software Solidworks. The model was studied for feasibility based on ANSYS. Then stress and strain of the impeller were discussed under the external loads. The results of the analysis provided verification for the reliable design of impellers.
Equipment Design ; Humans ; Respiration, Artificial ; instrumentation ; Software ; Stress, Mechanical ; Ventilators, Mechanical

OBJECTIVE:To study the chemical constituents in ethanol extract from the stem of Miao medicine Rubus multibracteatus. METHODS:The ethanol extract from the stem of Miao medicine R. multibracteatus was isolated and purified by silica gel column,preparative liquid chromatography and Sephadex LH-20 gel column,etc. The structure of compounds were analyzed and identified according to physicochemical properties and spectrum data(MS,hydrogen spectrum and carbon spectrum). RESULTS:Ten compounds were isolated from the ethanol extract of R. multibracteatus stem,i.e. 5,4′-dihydroxy-8-(3,3-dimethylally)-2″, 2″-dimethylpyrano [5,6∶6,7] isoflavone(1),3-hydroxy-1-(4′-hydroxy-3′-methoxyphenyl)propan-1-one(2),3β-hydroxysitost-5-en-7-one (3),Lupeol(4),Coniferaldehyde(5),E-p-hydroxy-coumaric acid(6),Genistein(7),1-O-p-coumaroylglycerol(8),Scopoletin(9), and Kaempferol(10). CONCLUSIONS:Compound 1-9 are isolated from the plants of R. multibracteatus for the first time,and Compound 2,5,8 are isolated from the plants of Rubus L. for the first time. The study lays the foundation for further development and utilization of R. multibracteatus.