Burns ; complications ; immunology ; physiopathology ; Humans ; Hypoxia ; etiology ; immunology ; physiopathology ; Ischemia ; etiology ; immunology ; physiopathology

OBJECTIVETo investigate the effect of Ca(2+) influx through L-type Ca(2+) channels on normal and hyperpolarized membrane potential of arteriole smooth muscle cells (ASMCs) in rats.

METHODSThe ASMCs isolated from normal rats and those with severe hemorrhagic shock were labeled with DiBAC4 (3) for membrane potential detection.

RESULTSCa(2+) influx caused hyperpolarization of the membrane potential in the normal ASMCs but depolarization in the cells from rats with hemorrhagic shock, and this effect could be inhibited by TEA.

CONCLUSIONCa(2+)-activated potassium channels activated by Ca(2+) influx through L-type Ca(2+) channels in normal ASMCs to cause hyperpolarization but leads directly to membrane potential depolarization in ASMCs from rats with severe hemorrhagic shock. This finding can be meaningful for treatment of vascular hyporeactivity in advanced stage of severe shock.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester ; pharmacology ; Animals ; Arterioles ; physiopathology ; Calcium Channel Agonists ; pharmacology ; Calcium Channels, L-Type ; metabolism ; Female ; Male ; Membrane Potentials ; drug effects ; Muscle, Smooth, Vascular ; physiopathology ; Potassium Channels, Calcium-Activated ; metabolism ; Rats ; Rats, Wistar ; Shock, Hemorrhagic ; physiopathology

The intestinal epithelial barrier serves a dual role: to keep harmful external agents out of the body and to allow beneficial nutrients to enter the body. Tight junction (TJ) is of crucial importance for the barrier function. Over the past 15 years, some of the molecular events underlying the epithelial barrier regulation have been described. This forum introduces briefly the molecular structure of TJ and its regulation in gut barrier. It was shown that gut barrier function was impaired as early as 5 minutes post burn and became worst by 4 hours. In this forum the mechanism of gut barrier injury in burns is described, and it includes 4 aspects: the phosphorylation of TJ protein and perijunctional actin-myosin ring, the reduction of TJ proteins expression, the endocytosis of TJ proteins, and the apoptosis and necrosis of the epithelial cells. It is well known that the increase in gut permeability promotes bacterial translocation in burns. Moreover, a new auto-digestion theory of gut in shock and MODS was recently raised. Therefore, protection against gut barrier damage has again been recognized as a therapeutic target in shock and MODS treatment.
Actins ; metabolism ; Apoptosis ; Burns ; metabolism ; Endocytosis ; Epithelial Cells ; metabolism ; Humans ; Intestinal Mucosa ; metabolism ; Membrane Proteins ; metabolism ; Multiple Organ Failure ; physiopathology ; Myosins ; metabolism ; Permeability ; Phosphorylation ; Shock ; metabolism ; Tight Junctions ; metabolism

Objective:To study the antisense oligonucleotide mediated inhibition on telomerase activity and cell proliferation of GBC-SD cell.Methods:We design the antisense,sense,and random oligonucleotide with phosphoric acid modification for the hTR(Human Telomerase RNA)template sequence.MTT and PCR methods were used to observe the inhibition on telomerase activity and cell proliferation of GBC-SD cell ,and fibroblast cells were used as control group.Results:PS-ODN can lead to the reduction of cell survival rate of GBC-SD cell,wich dosage dependence.Tne experimental group cell detected by scanning electron appeared apoptotic feature.Conclusion:PS-ODN can inhibit telomerase activity of GBC-SD cell effectively and induce the cell apoptosis.

OBJECTIVETo prepare zirconia toughened nano-composite alumina ceramic powder for dental application. Physical and chemical property of the prepared material were tested, and the effect of development technology on composite powder was also studied in this study.

METHODSNano-composite alumina powder was prepared by surface-induced precipitation method. The effect of pH value and dispersing agent content on volume of alumina suspension sediment was recorded. The effect of ultrasonic time on agglomeration was measured also. X ray diffraction (XRD) was used to analyze powder phase before and after the stabilizer was added. Scanning electronic microscope (SEM) was applied for characterizing the specimen.

RESULTSThe dispersion was better at pH=9 and wt (dispersing agent) = 0.2% approximately 0.3%. Selecting proper ultrasonic time can decrease the agglomeration of powders and lower the average particle size. XRD analysis indicated that the phase composition of the prepared nano-composite ceramic powder was shown as alpha-Al2O3, t-ZrO2 and a small amount of m-ZrO2 after the addition of stabilizer. Through SEM observation, nanometer-sized ZrO2 particles (80 approximately 100 nm) were uniformly located on the surface of submicrometer alumina grains.

CONCLUSIONSBy choosing appropriate preparation method, weakly agglomerated powders with fine particle size can be obtained. The zirconia part of nano-composite powder was transmitted to partially stabled zirconia after the use of stabilizer.

Aluminum Oxide ; chemistry ; Dental Porcelain ; chemistry ; Hydrogen-Ion Concentration ; Powders ; Zirconium ; chemistry

Exposure of gingival margin is frequently observed in anterior teeth aesthetic restoration. How to obtain an expected result is a significant challenge during prosthodontic treatment. The present article discussed gingival biotype, conditions of periodontal tissue, location of margin of restoration, gingival retraction, and provisional restoration, etc, which would affect the final aesthetic outcome of anterior teeth restorations. The aim of this article is to figure out how to effectively avoid the exposure of gingival margin in anterior teeth aesthetic restoration, and to improve the finally aesthetic outcome of anterior teeth restoration.
Esthetics ; Esthetics, Dental ; Gingiva ; Humans ; Prosthodontics

To investigate and compare the expression of intercellular adhesion molecule-1 (ICAM-1) in different organs of the mice with endotoxic shock induced by lipopolysaccharide (LPS), protein and mRNA of ICAM-1 were measured by Western blotting and RT-PCR respectively in different organs of BALB/c mice administered intraperitoneally with 5 mg/kg LPS. The results showed that the constitutive expression of ICAM-1 protein and mRNA was the greatest in the lungs, followed by the spleen, kidney and intestine. After LPS stimulation, the upregulation of ICAM-1 was still greatest in the lungs, followed by the liver, spleen, heart, kidney and intestine. Compared with the normal mice, the expression of ICAM-1 protein in endotoxic shocked mice increased by 4.5-fold in the lungs, 3.0-fold in the kidney, 1.5-fold in the spleen; the expression in the liver and heart was negative under normal condition and changed into positive during endotoxic shock; but ICAM-1 expression in the intestine did not change significantly. The expression of ICAM-1 mRNA also increased consistently. These data highlight that LPS can up-regulate ICAM-1 protein and mRNA expression in different tissues of the mice with endotoxic shock. The difference in ICAM-1 expression among the organs may lead to different sensitivity of organ damage in endotoxic shock. This suggests that inhibition of ICAM-1 expression may be a useful principle for prevention and treatment of endotoxic shock.
Animals ; Intercellular Adhesion Molecule-1 ; biosynthesis ; Kidney ; metabolism ; Lipopolysaccharides ; Lung ; metabolism ; Male ; Mice ; Mice, Inbred BALB C ; RNA, Messenger ; biosynthesis ; Shock, Septic ; chemically induced ; metabolism

OBJECTIVETo evaluate the safety and efficacy of self-expending metallic stents (SEMS) as bridge to surgery versus emergency surgery for left-sided malignant colorectal obstruction.

METHODSA comprehensive literature search of CENTRAL, PubMed, EMBASE, Medline, Ovid LWW, CMB, CNKI and Wanfang Databases were performed for all randomized controlled trials or retrospective studies comparing self-expending metallic stents as bridge to surgery(SABS group) with emergency surgery (ES group). A meta-analysis was carried out by RevMan5.1 software on the outcomes concerning safety and efficacy of the two groups.

RESULTSFourteen studies matched the criteria including 1083 patients. Five were randomized controlled trials and nine were retrospective analysis. Compared with the ES group, the SABS group had a lower short-term mortality(RR=0.52, 95% CI:0.30-0.93, P<0.05), lower overall complications(RR=0.46, 95% CI:0.31-0.70, P<0.05), higher resection rate(RR=1.90, 95%CI:1.33-2.70, P<0.01), shorter operative time(MD=-59.77, 95%CI:-87.51--32.04, P<0.01), and shorter interval to first flatus(MD=-10.78, 95%CI:-16.67--4.90, P<0.01). There were no statistically significant differences between the two groups in permanent stomy and hospital stay.

CONCLUSIONThe safety and efficacy of self-expending metallic stents as bridge to surgery for left-sided malignant colorectal obstruction is superior to emergency surgery.

Colectomy ; Colorectal Neoplasms ; complications ; surgery ; Emergencies ; Humans ; Intestinal Obstruction ; etiology ; surgery ; Stents ; Treatment Outcome

OBJECTIVEThe purpose of this study was to evaluate the in vitro cytotoxicity of novel Comfort denture adhesive (Comfort-DA), which was developed by the authors, to human oral fibroblasts (HOFs).

METHODSA sample of Comfort-DA was prepared and extracted in culturing medium to prepare the eluate. Then the eluate was diluted by culturing medium to 50% and 75% concentration for the assessment of cytotoxicity by tetrazolium bromide (MTT) colorimetric assay. Wells containing fresh medium alone were served as control. Cell viability was recorded by optical density after culturing in an atmosphere of 5% CO2 and 95% air at 37 degrees C for 2, 3 and 4 days, respectively. The viability of HOF cells was evaluated by MTT assay to investigate cell proliferation. Optical density (OD) was measured by a spectrophotometer at 490 nm. Then evaluating the cytotoxicity grade in test groups according to the means of cell proliferation. ANOVA was used to test the statistical significance.

RESULTSThe statistical analysis of the results of MTT cytological assay indicated significant difference (P < 0.05) in OD (indicate cell viability) between all concentrations of Comfort-DA and the control at all incubation times. The results of cell proliferation percentage also showed that the cytotoxicity grade of tested material only displayed "0-2".

CONCLUSIONThe generally favorable in vitro cytotoxicity of the Comfort-DA formulations indicates that this product may be an efficacious denture adhesive.

Adhesives ; toxicity ; Adolescent ; Biocompatible Materials ; chemistry ; toxicity ; Cell Division ; drug effects ; Cell Survival ; drug effects ; Cells, Cultured ; Denture Retention ; Fibroblasts ; cytology ; drug effects ; Humans ; Male ; Periodontium ; cytology ; drug effects ; Tetrazolium Salts ; Thiazoles ; Toxicity Tests ; methods

OBJECTIVETo evaluate mechanical properties of zirconia toughened composite alumina (ZTCA) ceramic used for dental application, characterize the effect of different zirconia contents on mechanical properties of ZTCA.

METHODSDental alumina ceramic powder was prepared by sol-gel method, and four groups of ZTCA powders with different zirconia contents were prepared via surface-induced precipitation method. All five groups of powders were dry-pressed and then sintered to make standard specimens for mechanical tests. The flexural strength and fracture toughness of these specimens were evaluated, and the fractography was characterized by scanning electronic microscope (SEM). Phases of ZTCA were also determined using X-ray diffraction (XRD).

RESULTSIt was found that the flexural strength of ZTCA ceramics increases with ZrO2 content up to 30%, and decreases thereafter. ZTCA specimens containing 30% ZrO2 show the highest flexural strength, and the corresponding fracture toughness was 1.85 MPa x m(1/2). The XRD results of ZTCA ceramics showed the phase constituents of alpha-Al2O3, t-ZrO2 and a small amount of m-ZrO2.

CONCLUSIONThe strengthening and toughening mechanisms of ZTCA depend on ZrO2 content. In the range of 15%-30% ZrO2, the stress-induced phase transformation toughening mechanism is dominant, while microcrack and deflection exist as the additional toughening mechanism when ZrO2 addition amount is above 30%.

Aluminum Oxide ; Ceramics ; Dental Porcelain ; Materials Testing ; Zirconium