Objective To study the adverse effects of PM2.5 from Beijing urban areas on human lung adenocarcinoma cells(A549) and the expression of NF-?B in the cells. Methods A549 cells were treated with PM2.5 at 25,50,100 and 200 ?g/ml for 24 h. Cytotoxicity of PM2.5 was measured by MTT assay. The activity of NF-?B was measured by ELISA assay. Western blot method was used to detect the expression of NF-?B and NO levels was determined by using the nitrate reductase method. Results PM2.5 could induce A549 cell proliferation at low doses,but inhibit cell proliferation at high doses. The activity of NF-?B increased in the cell nucleus,but decreased in the cytoplasm after exposure to PM2.5 with a significant dose-dependent manner(P

AIM: To explore the skills and characteristics of corneal neovascular model in rat induced by micropocket assay. ·METHODS: Nine eyes of nine Sprague-Dawley rats were studied. Pellets made of vascular endothelial growth factor (VEGF), poly-2-hydroxylethylmethacrylate and sucralfate were implanted into the corneal stroma nocloser than 1mm from the limbus. Biomicroscopic features of corneal neovascular were observed on 1,3, 5, 7th day after the implantation. ·RESULTS: On day 1 after operation, the limbal vessels were dilated, with no angiogenesis appeared. On day 3, angiogenesis began to invade peri-cornea with a brush shape, the area of CNV was (2.23±0.59) mm2. On day 5, new vessels reached the lower margin of pellet densely, the area of CNVwas (6.81±1.35)mm2. On day 7, new vessels continued to elongate, parts of them extended as loops toward the pellet, the area of CNV was (8.92± 1.79)mm2. Neither hyphema or other complications occurred.·CONCLUSION: Corneal neovascular induced by micropocket assay in rat grows steadily, with no complication, and is suitable for quantitative researches.

Background Microvessels are composed of two interacting cell types: endothelial cells and pericytes. Over the past decades, studies of corneal angiogenesis have concentrated mainly on endothelial cells, while interest in pericytes has lagged behind. Objective The present study aimed to investigate the recruitment of vascular endothelial cells and pericytes in rat corneas after alkali burn. Methods Corneal alkali burn models were established in the right eyes of 36 adult SPF SD rats by putting 4 mm medicators containing a 1% 1 mol/L NaOH solution at the central corneas for 30 seconds, and 3 matched normal rats were used as controls. Corneas were excised 1,2,3,5,7 and 10 days after surgery. Frozen sections that parallel with the corneoscleral limbus were constructed. Double immunofluorescence staining was used to observe the dynamic expression of CD31 and α-smooth muscle actin (α-SMA) in corneal tissue for the evaluation of the number of endothelial cells and pericytes. The pericyte coverage index (PCI) was calculated to quantify the recruitment of pericytes to neovascular sites. The use of experimental animals followed the Statement of Association for Research in Vision and Ophthalmology. Results CD31 was expressed in the superficial stromal layer of the cornea on the 1 st day, showing the presence of red fluoresence. The positive cell number for CD31 was gradually increased with the passage of time and proceeded into the deep stromal layer from days 2 through 5 but decreased after that. However,α-SMA was positively expressed on the 2nd day in the cornea after alkali burn with the presence of green fluorescence. The positive cell number for α-SMA was less than those of CD31 throughout the experimental period. The PCI was 0, 16.07%, 11.95%, 43.84%, 73.97% and 86. 21% , respectively, 1,2,3,5,7 and 10 days after surgery. Conclusion Pericytes recruitment to corneal new vessels may play a key role in the stabilization and maturation of angiogeneis.

Objective To explore the clinical efficacy of 1251 stent implantation in treatment of malignant tracheal stenosis with the help of ventilation catheter under local anesthesia.Methods Totally 180 consecutive patients with malignant tracheal stenosis underwent 125I airway stent implantation were analyzed retrospectively.The anhelation grade,oxygen saturation and respiratory rate before and after operation were recorded and analyzed,125I stent situation,clinical symptoms and survival situation were followed up after operation.Results The success rate of 125I stent placement was 100％ (180/180),and the stent type was tubular stent in 132 cases,Y-shaped stent in 34 cases,and L-shaped stent in 14 cases.Dyspnea was significantly relived in all patients.Oxygen saturation and respiratory rate improved from (80.60±3.87)％ and (29.36± 3.20)times/min before operation to (94.31±3.40)％ and (19.29±2.19)times/min after operation (t=-30.52,35.09,both P＜0.01).Patients were followed up 3-13 mouth after operation,and stent restenosis were occurred in 6 patients.The lifetime was 49-401 days and the average lifetime was (182±94) days.The 60-day survival rate was 0.99 and the 180-day survival rate was 0.65.Conclusion 125I stent implantation in treatment of malignant tracheal stenosis with the help of ventilation catheter under local anesthesia is a safe and effective method.

Animals ; Electroencephalography ; Heart ; physiopathology ; Immersion ; physiopathology ; Rats ; Rats, Wistar ; Seawater

An enhance matrix removal ( EMR) QuEChERS method for simultaneous determination of 22 triazine herbicide residuals such as atrazine, propazine, terbumeton, and desmetryn in corn was established and validated. The corn samples were initially extracted with acetonitrile ( MeCN ) in high-speed homogenization, and the targeted pesticides were prepared using EMR-Lipid (Enhanced matrix removal-lipid) method to clean-up and EMR-Polish to salt out, separated on a Kinetex XB-C18 with acetonitrile and 0. 1%formic acid aqueous as eluant, and then detected by UFLC-MS / MS under positive ( ESI+ ) electrospray ionization and MRM models. The average recoveries of 22 herbicides were in the range of 72% -105% at the spiked level of 5, 10 and 20 μg / kg. The relative standard deviations were less than 15% . In the method validation, correlation coefficients were higher than 0. 993 with the linear range from 1. 0 μg / L to 50 μg / L. The qualitative analysis and quantitative analysis were investigated by UFLC-MS / MS and matrix-matched calibration curves. The results showed that EMR QuEChERS combined with UFLC-MS / MS purification method was rapid, accurate and sensitive for the determination of 22 triazine herbicides residues in corn.

Helicobacter pylori (Hp) infection is an important cause of chronic gastritis and peptic ulcer, but their pathogenesis is unclear. The role of gastric mucosal barrier dysfunction induced by impaired structure and function of tight junction in the pathogenesis of Hp-associated gastric diseases has received considerable attention in recent years. Tight junction is composed of a variety of proteins and molecules, including 3 integral membrane proteins (occludin, claudins, and junctional adhesion molecules) and a cytoplasmic protein (zonula occludens). This paper mainly describes the composition and function of various tight junction proteins, changes in tight junction protein function induced by Hp infection and their relationship with the incidence of gastric diseases, and the significance of enhancing the tight junction protein function in the prevention and treatment of Hp-associated gastric diseases.
Helicobacter Infections ; complications ; Helicobacter pylori ; pathogenicity ; Humans ; Oxidative Stress ; Stomach Diseases ; etiology ; Stomach Neoplasms ; etiology ; Tight Junction Proteins ; analysis ; chemistry ; physiology

Hyponatremia is relatively common in patients with neurologic disorders, while its diagnosis and treatment remain controversial. Osmotic demyelination syndrome (ODS) has shown to be closely associated with hyponatremia. ODS patients often present as central pontine myelinolysis, extrapontine myelinolysis, or both. This article reviews the clinical manifestations, pathogenesis, and risk factors of ODS in patients with hyponatremia caused by neurologic disorders.
Demyelinating Diseases ; etiology ; therapy ; Humans ; Hyponatremia ; complications ; etiology ; Nervous System Diseases ; complications

Objective To investigate the com and pepper fluorine in Zhenxiong county of Yunnan province, as well as the change of com and pepper fluorine after baked by coal, clay-mixed with cual for a relatively long-term, in order to provide a scientific basis for reducing fluorine intake. Methods The endemic areas of Yile, Wufeng's Songlinwan, Tangfang and Wufeng's Wugu in Zhenxiong county, and a non-endemic area Xiaguan in Dali city were selected as study sites. Ten samples of fresh corn and pepper were collected in each region, and fluorine was determined using acid leaching/potentiometry freshly and after baking or drying for 10 days or 4 months, respectively. Results The fluorine content of local fresh corn in Xiaguan of Dali city and Yile,Wufeng's Songlinwan, Tangfang, Wufeng's Wugu in Zhenxiong county were (1.31 ± 0.13),(1.65 ± 0.64),(1.92 ±0.37), (2.32 ± 0.49), (1.98 ± 0.66)mg/kg, respectively, and there were statistically significant differences across the regions(H = 27.871, P ＜ 0.05). The fluorine content of corn samples after baking or drying for 4 months were ( 1.82 ± 0.17), (26.43 ± 12.03), (39.27 ± 8.09), ( 14.27 ± 4.37), ( 14.33 ± 1.73)mg/kg, respectively, which were significantly higher than that of the fresh com in the corresponding region(all P ＜ 0.05 ), and there were statistically significant differences across the regions(H = 42.512, P＜ 0.05). The fluorine content of the local fresh chili were (3.34 ± 1.08), (3.44 ± 0.55), (3.47 ± 0.74), (3.46 ± 0.93)mg/kg, respectively, in the 4 observed places in Xiaguan of Dali city and Yile, Wufeng's Songlinwan, Tangfang in Zhenxiong county, and there were no statistically significant differences across the regions (F = 0.052, P ＞ 0.05 ). The fluorine content of pepper samples after baking or drying for 4 months were (7.01 ± 1.64), (226.07 ± 83.69), (179.36 ± 148.37), (54.51 ± 34.67)mg/kg,respectively, which were significantly higher than that of the fresh pepper in the corresponding region(all P ＜ 0.05 ),and there were statistically significant differences across the regions(H = 28.822, P ＜ 0.05). Conclusion Corn and chili fluorine is significantly increased after baked with coal and clay-mixed with coal by farmers in Zhenxiong county, a coal- burning borne endemic fluorosis area of Yunnan province.

BACKGROUNDAcinetobacter baumannii is one of the main gram-negative bacilli in clinical practice. Nosocomial infections caused by multi-drug resistance Acinetobacter baumannii is very difficult to treat. This study was designed to investigate the antimicrobial resistance characteristics and four resistant gene expressions of aminoglycoside-modifying enzymes including N-acetyltransferases and O-phosphotransferases in Acinetobacter baumannii.

METHODSBacterial identification and antimicrobial susceptibility test were performed by Phoenix system in 247 strains of Acinetobacter baumannii. Minimal inhibitory concentrations (MICs) of seven aminoglycosides including gentamicin, amikacin, kanamycin, tobramycin, netilmicin, neomycin and streptomycin in 15 strains of multi-drug resistant Acinetobacter baumannii were detected by agar dilution. Four aminoglycoside-modifying enzyme genes were amplified by polymerase chain reaction (PCR) and verified by DNA sequencer.

RESULTSThe resistance rates of 247 strains of Acinetobacter baumannii against cefotaxime, levofloxacin, piperacillin, aztreonam, tetracycline, ciprofloxacin and chloramphenicol were more than 50%. Imipenem and meropenem showed high antibacterial activities with resistance rates of 3.2% and 4.1%. MIC50 and MIC90 of gentamicin, amikacin, streptomycin and kanamycin in 15 strains of multi-drug resistant Acinetobacter baumanii were all more than 1024 mg/L, and the resistance rates were 100%, 100%, 100% and 93.3%, respectively. But their resistance rates to tobramycin, netilmicin and neomycin were 86.7%, 93.3% and 46.7%, respectively. Three modifying enzyme genes, including aacC1, aacC2 and aacA4 genes, were found in 15 strains, but aphA6 had not been detected. Their positive rates were 93.3%, 20.0% and 20.0%, respectively. These three genes existed simultaneously in No.19 strain. Nucleotide sequences of aacC1, aacC2 and aacA4 genes shared 100%, 97.9% and 99.7% identities with GenBank genes (AY307113, S68058 and AY307114).

CONCLUSIONMulti-drug resistant Acinetobacter baumannii strains are rapidly spreading in our hospital, and their resistance to aminoglycosides may be associated with aminoglycoside-modifying enzyme gene expressions.

Acinetobacter baumannii ; drug effects ; enzymology ; genetics ; Aminoglycosides ; metabolism ; pharmacology ; Base Sequence ; Drug Resistance, Multiple, Bacterial ; Gene Expression Regulation, Bacterial ; Genotype ; Microbial Sensitivity Tests ; Molecular Sequence Data