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.

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

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

This article devotes itself to evaluating the biocompatibility of synthetic macromolecular resin class of Comfort denture adhesive, which was developed by the present authors. Acute toxicity, haemolysis, cytotoxicity, sensitization and oral mucous stimulation were tested with standard method (ISO7406-1997 and YY0268-1995). The results showed that no toxic effect was observed with in vivo tests and no cytotoxic effect was observed with in vitro MTT assay. Haemolysis rate of the material (2.95%) indicated good hemaocompatibility. No local mucous membrane irritation reaction was noted after the relevant tests. The developed Comfort denture adhesive exhibited good biocompatiblility.
Adhesives ; pharmacology ; Animals ; Cells, Cultured ; Denture Retention ; Denture, Complete ; Humans ; Materials Testing ; Mouth Mucosa ; drug effects ; physiology ; Rabbits ; Rats ; Resins, Synthetic ; pharmacology

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 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

OBJECTIVETo investigate the changes in endothelial cytoskeletal reorganization and the role of Rho in the signal transduction pathway.

METHODSECV304 cells were cultured and randomly divided into following groups: i.e. sham (with normal rat serum treatment), burn (with burn rat serum treatment), Y (with 30 micromol/L Rho kinase inhibitor Y-27632 treatment), burn plus Y (pretreatment of cells with burn serum before treated with 30 micromol/L Y-27632), Y plus burn (pretreatment of cells with Y-27632 for 1 hour before treated with burn serum), LPA (with normal rat serum and 13 micromol/L LPA), and LPA plus Y (pretreatment of cells with LPA before treated with Y-27632) groups. The indices were examined at 6, 7 and 8 posttreatment hours (PTH) in all groups except in Y group. The endothelial morphology was observed with HE staining. Endothelial cytoskeleton was observed by dual-fluorescence labeling of filamenta (F) with Rhodamine-phalloidin and monomer (G) with oregon green labeled DNAase. The actin content in the cells in all groups was measured with flow cytometry.

RESULTSIn sham and control group, the cells were in fusiform or polygonal shape, with satisfactory growth; filamentous actin (F-actin) was mainly distributed in the peripheral site of the cytoplasm and formed peripheral filamental band. The cells became confluent to form a single layer with reticular structure. Globular actin (G-actin) was concentrated in the nucleus and per nucleus. In burn group, after 6 hours of burn serum treatment, the ability of cells to adhere to vessel wall was weakened, and a striking reorganization of the actin cytoskeleton and the formation of the stress fibers were found. Furthermore, the fluorescent intensity of the peripheral filament bands was weakened, and dispersed actin monomers were seen in the cytoplasm. This reaction was enhanced along with elapse of stimulation time. In burn plus Y or Y plus burn group, the cells grew and adhered well to the wall of culture vessel. The distribution of the filamentous actin was the same as the sham group, while the stress fiber decreased in amount obviously. The structure of globular actin was condensed with little G-actin in the cytoplasm. The changes in actin cytoskeleton in LPA group was similar to that in burn group. The effects of LPA on actin reorganization could also be reversed by Y-27632. The content of F-actin in burn group at 6 PTH (0.63 +/- 0.07) was lower than that in sham group (0.75 +/- 0.08), while the content of G-actin in burn group (1.28 +/- 0.27) was higher than that in sham group (1.16 +/- 0.16, P > 0.05).

CONCLUSIONBurn serum induces vascular endothelial actin cytoskeleton reorganization in endothelial cells via the Rho-dependent signal pathway. Similar to the effect of LPA, this effect could be reversed by Y-27632.

Actins ; metabolism ; Amides ; pharmacology ; Animals ; Burns ; blood ; metabolism ; Cells, Cultured ; Cytoskeleton ; metabolism ; Endothelial Cells ; metabolism ; Endothelium, Vascular ; Humans ; Male ; Pyridines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Serum ; metabolism ; Signal Transduction ; rho-Associated Kinases ; antagonists & inhibitors ; metabolism