Objective To construct a qseC-deleted mutant strain of E.coli by Red recombination and to study the effect of qseC gene on biofilm formation in the mutants.Methods The chloramphenicolresistant gene flanked by homologues of target genes was amplified by PCR and electro-transformed into E.coli MC1000.When induced by L-arabinose,the plasmid pKD46 could express three recombinant proteins of λ-prophage,which led to the replacement of target gene(qseC) with chloramphenicol-resistant gene.Then the chloramphenicol-resistant gene was eliminated by FLP-promoted recombination events.The biofilm formation of wild-type and mutant strain was detected by crystal violet staining.Results The qseC-deleted mutant of E.coli was confirmed by various PCR and DNA sequencing.Gene qseC was completely deleted.There was no significant difference in growth ability between the qseC mutant strain and the wild-type strain MC1000.The biofilm formation of wild-type and mutant strain was quantified by crystal violet staining.The absorbance determined with a plate reader at 570 nm was 1.00±0.15 and 0.47±0.10 respectively.Conclusion The qseC-deleted mutant of E.coli was constructed successfully.And the qseC gene plays an important role in regulation of biofilm formation in E.coli.

Objective To study the effect of epinephrine on biofilm formation of the qseC-deleted mutant of Escherichia coli on biomaterial.Methods The strains used in this study are Escherichia coli MC1000 and MC1000AqseC.LB was used for all the experiments.To determine the effect of epinephrine on motility,halos were measured in LB medium at 37℃ in the presence of epinephrine(50 μmol/L).LB with epinephrine and without epinephrine were used,and then the experiment of bacterial biofilm formation on PVC material was taken.The relative amount of biofilm was estimated.The thickness of bacterial community and bacterial community quantity in the unit area on PVC materials were measured by confocal laser scanning microscope( CLSM),and the surface structure of biofilm formation was observed by scanning electron microscope(SEM).Results The mutant strain formed less biofilm than the wild-type strain in LB.The increment in motility of wild-type strain due to epinephrine addition was shown,but mutant strain is unaffected.Similarly,biofilm formation of the wild-type strain was increased by epinephrine,but epinephrine did not affect the biofilm formation of the qseC mutant.The CLSM and SEM showed that epinephrine stimulated biofilm formation of wild-type strain on PVC materials,but had no effect on qseC-deleted mutant strain.Conclusion Epinephrine increases Escherichia coli biofilms on biomaterials through qseC.

Objective To investigate the role of quorum sensing Escherichia coli regulator C (qseC) in intestinal bacterial translocation in rats subjected to hemorrhagic shock.Methods Thirty Sprague-Dawley rats,weighing 250-300 g,were randomly divided into 5 groups (n =6 each):control group (group C),MC1000-sham shock group (group M-SS),MC1000qseC-sham shock group (group △-SS),MC1000-hemorrhagic shock group (group M-HS),and MC1000△ qseC-hemorrhagic shock group (group △-HS).The rats drank 150 μg/ml of disinfect water containing streptomycin in 3 consecutive days to inhibit the autochthonous flora in the intestinal tract.From 4th day,the rats were fed with Escherichia Coli MC1000 or MC1000△ qseC 1 ml/100 g by gastric perfusion once a day for another 3 consecutive days in the other 4 groups,while the rats were fed with normal saline instead in group C.Hemorrhagic shock was induced by blood-letting.The mesenteric lymph node (MLN),spleen and liver specimens were obtained at 24 h after operation for bacterial culture and the bacteria were identified.Bacterial translocation from gut to MLN,spleen and liver was observed and the number of bacteria in MLN,spleen and liver tissues were counted.Results The rate of bacterial translocation was significantly higher,and the number of bacterial colonies in MLN,spleen and liver tissues and the total number of bacterial colonies were significantly larger in groups M-HS and △-HS than in group C,and in group M-HS than in groups M-SS and △-SS (P ＜ 0.05).The rate of bacterial translocation was significantly lower,and the number of bacterial colonies in MLN,spleen and liver tissues and the total number of bacterial colonies were significantly smaller in group △-HS than in group MHS.Conclusion QseC is involved in the intestinal bacterial translocation following hemorrhagic shock in rats.

Objective To establish a HPLC method for determination of naringenin and apigenin in Premna fulva. Methods The SHISEIDO￣SPOLAR C18(250 mm×4.6 mm,5μm) was used as analytical column.The mobile phase consisted of methanol￣0.2% phosphoric acid (42:58) with isocratic elution at a flow rate of 1.0 mL.min-1 .The detection wavelength of naringenin and apigenin was 288 nm and 340 nm, respectively.Column temperature was set at 35 ℃ , the injection Volume was 10 μL. Results Naringenin and apigenin had a good linear relationship in the concentration range of 0.180 ~ 3.60 μg (r =0.999 9) and 0. 0052 ~ 0. 1040 μg ( r = 0. 999 9), respectively. Conclusion The method is accurate and reliable. It is appropriate for the quantitative determination of naringenin and apigenin in Premna fulva and its preparations.

Objective To evaluate the relationship between quartz's deposit and expression of NF-κB in non-small cell lung cancer (NSCLC) lung tissues in Xuanwei, Yunnan Province, and to clarify the role of quartz in Xuanwei NSCLC's carcinogenic mechanism. Methods As research objects, the lung tissues of NSCLC and lung benign lesions after surgical resection were collected from July 2009 to September 2015 at the Third Affiliated Hospital of Kunming Medical University. Firstly, the transmission electron microscopic (TEM) with energy dispersive X-ray analyzer (EDS) was used for observation of crystalline deposit and local pathological changes. Secondly, expression level of NF-κB had been analysed and a correlation analysis with particle size of SiO2 crystal in the same lung sample was made. Results The occurrence rates of quartz in Xuanwei NSCLC lung tissues were above non-Xuanwei NSCLC and benign lung tissues (P<0.01);the average particle size of SiO2 crystal was (226 ± 120) nm × (237 ± 163) nm in Xuanwei NSCLC group and it was smaller than the other two groups; In Xuanwei NSCLC group, the expression level of NF-κB was significantly higher than non-Xuanwei and benign lung tissues (P< 0.01), but there was no significant difference between cancer tissues and normal lung tissues in the group (P>0.05). The expression level of NF-κB was generally increasing when quartz 's size became smaller. Conclusion Quartz 's deposit may play a certain role in carcinogenic mechanism of lung cancer in Xuanwei, the smaller the particle size, the greater the cytotoxicity.

BACKGROUND: It is confirmed that pathogenicity of biomaterials-centered infection is positive correlated to bacterial biofilm formation of Staphylococcus epidermidis on the surface of catheter-related materials. OBJECTIVE: To analyze the relations between expressions of central venous catheter-related Staphylococcus epidermidis icaA, icaD, transforming growth factor β1 (TGF-β1) and formation of bacterial biofilm. METHODS: The type of Staphylococcus epidermidis in lung cancer cases with catheter-related bloodstream infections (CRBSI) was indentified, followed by bacterial genomic DNA extraction. The expression of biofilm formation-related genes icaA, icaD mRNA and phenotype of biofilm were detected by PCR. The serum TGF-β1 levels in cases with or without CRBSI were measured by enzyme-linked immunosorbent assay.RESULTS AND CONCLUSION: The expression of Staphylococcus epidermidis operon icaA and icaD gene was positive correlated to biofilm formation in lung cancer cases with CRBSI (P < 0.01); particularly, the TGF-β1 levels in CRBSI cases were greater than that of non-CRBSI cases (P < 0.05). The results demonstrated that, central venous catheter infection causes positive Staphylococcus epidermidis icaA and icaD gene expressions in lung cancer cases and is prone to form biofilm, high level of peripheral TGF-β1 may play a positive role in bacterial biofilm formation.

Xuanwei district in Yunnan Province of China has pretty high incidence of lung cancer in China, even a- round the world. Studies have shown that there exists a close relationship between lung cancer and local indoor air pollution caused by Bituminous coal. Considering that the indoor air pollution in Xuanwei District is caused by "open fireplace", an indoor air pollution simulation system was designed, and an F344 rats lung damage model was estab- lished for this indoor air pollution fireplace. The model is based on indoor air pollution simulation system with signal multiplexer control and multi-channel acquisition, and mining PID algorithm was used for polynomial fitting to each test point, and a relatively constant PM2. 5 air pollution status was simulated. The results showed that the system could simulate a variety of states of air pollution, provide a new test method for evaluation of human injury caused by indoor air pollution and a new idea for the study of the incidence of lung cancer in Xuanwei district and other places.
Air Pollution, Indoor ; analysis ; Animals ; China ; Coal ; adverse effects ; Humans ; Incidence ; Lung ; drug effects ; pathology ; Lung Neoplasms ; epidemiology ; Models, Biological ; Particulate Matter ; analysis ; Rats ; Rats, Inbred F344

Objective To investigate the correlation between patients clinical characteristics and the number and subtype of circulating tumor cells (CTCs) from peripheral blood of perioperative hepatocellular carcinoma (HCC)patients by SE-iFISH.Methods 20 HCC patients undergoing radical resection were enrolled from June 2015 to June 2016.The SE-iFISH technique was used to separate and identify circulating tumor cells.The pathology and clinical data were used to evaluate patients survival in combination with CTCs characteristics.Results A total of 347 CTCs were detected,of which 114 were triploid,64 were tetraploid,and 165 were pentaploid.The number of preoperative CTCs and the number of preoperative triploids was significantly correlated with the presence of vascular tumor emboli (Z1 =-2.080,P =0.037,Z3 =-2.321,P =0.020) and TNM staging(Z2 =-2.148,P =0.032,Z4 =-2.526,P =0.012).Postoperative patients disease-free survival in high CTCs detection group was significantly shorter than that of CTCs low expression group (x2 1 =7.486,P =0.006,x22 =12.056,P =0.001).Conclusion Detection of the number and the specific subtypes of CTCs with SE-iFISH strategy in patients with HCC help predict treatment efficacy and prognosis.

Background and objective This study was conducted to evaluate the effects of the accumulation-associated protein (Aap) gene and transform growth factor-beta 1 (TGF-β1) on the bioiflm formation of lung cancer-related Staphylococcus epidermidis (SE). Methods Species identification was performed to isolate SE strains from clinically im-planted materials in lung cancer patients. Stable genetic aggregated proteins, which are associated with negative and positive isolates, were obtained. hTe bioiflm-formation ability of the SE Aap gene was determined by PCR. Density gradient method was used to extract peripheral blood mononuclear cells from patients with non-small cell lung cancer. Atfer 30 h, these cells were co-cultured with A549 at different TGF-β1 concentrations. hTe supernatant was then combined with SE Aap+and SE Aap-strains and co-cultured with a medical silicone rubber. A semi-quantitative adhesion test was performed for each bacterial bioiflm formation. Scanning electron microscopy was also conducted to observe the microcosmic condition of this material on the bacterial bioiflm surface. Results hTe Aap gene was closely related to SE bioiflm formation. At 10 ng/mL, 20 ng/mL, and 40 ng/mL, SE Aap+bioiflm on the medical silicone rubber surface was thicker in the TGF-β1 group than in the control group. No signiifcant differences were found between TGF-β1 groups. For the SE Aap-strains, no evident bioiflm was formed in TGF-β1 and control groups. Conclusion In plant material-related infection of lung cancer patients, SE Aap+strain easily forms bioiflm. Furthermore, TGF-β1 was conducive for the bioiflm formation of SE Aap+strains.

Background and objectivehTe high incidence of lung cancer in Xuanwei, China, has become an im-portant restricting factor for livelihood development, thus exerting local social and economic impacts. Coal is the main fuel of the local community and also the main source of indoor pollution. hTis study aims to explore the coal combustion inhalable ifne particulate matter (PM2.5) and its component output differences in different areas of Xuanwei, Yunnan. Moreover, the aim of this study is to investigate the relationship between inhalation of ifne particles and high incidence of local lung cancer.Meth-odsFor combustion test, coal mines designated as C1, K7 and M30 were collected from LaoLin Colliery of Laibing Town, Huchang Colliery of Baoshan Town, and Taiping Colliery of Wenxing Town in Xuanwei, respectively. PM2.5 of indoor air was weighed, analyzed for elemental composition, and morphologically compared. hTe pathological specimen of lung cancer pa-tients in Xuanwei who underwent operation was observed through electron microscope.Results hTe PM2.5 concentrations in indoor air were (8.244 ±1.460) mg/m3 (C1), (5.066±0.984) mg/m3 (K7), and (5.071±1.460) mg/m3 (M30). hTe differences among pairwise comparisons were statistically signiifcant (P=0.029). hTe iflter impurities of C1 coal seam primarily includeSi- and O-enriched compounds. Moreover, three membranes that comprised other elements, including C, S, and Si, were ob-served. hTese membranes were evident from the aggregation of silica and a Ca-Al membrane. Compared with that of other coal seams, C1 coal generated a mass of impurities, in which several particles have irregular shape. We found nanoscale ifne particles in some specimens of Xuanwei lung cancer patients.ConclusionhTe produced combustion of C1 coal was different from that of K7 and M30 coal. PM2.5 composition may be associated with the high local incidence of lung cancer.