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.

Objective: To compare the effects of 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP)- and silane-based primers with those of MDP-based primers on zirconia-resin bonding via multiple levels of aging. Methods: Zirconia blocks were divided into 4 groups (n = 21) according to the primer used: MDP-based Z-Prime Plus (ZP), silane-based Monobond-S (MS), MDP- and silane-based Clearfil Ceramic Primer (CCP) and no primer (Blank). After pretreatment with or without the primers followed by bonding with cement Duo-Link, each group was subdivided into 3 subgroups (n = 7) according to aging level: 24 hours of water storage at 37 ℃ (24 h), 30 days of water storage at 37 ℃(30 d), and 30 d plus 3 000 thermal cycles (30 d/TC). After aging, shear bond strength (SBS) tests and failure mode analyses were conducted Results: ZP, MS and CCP groups had greater SBSs than did the BLANK group (P<0.01). From 24 h to 30 d, the shear bond strength significantly increased (P<0.05); however, the shear bond strength decreased significantly from 30 d to 30 d/TC (P<0.01) and fell below baseline (30 d/TC vs. 24 h, P<0.01). Within the primer groups, CCP exhibited a higher SBS than ZP and MS at each aging level (P<0.001). The bonding strength of ZP was greater than that of MS at 30 d (P = 0.029) but lower than that of MS at 30 d/TC (P = 0.037). From 30 d to 30 d/TC, the percent decrease in the bonding strength of ZP was significantly greater than that of MS (82.43% vs. 64.90%). Conclusion MDP-based primers function better for zirconia-resin bonding when they contain silane coupling agents.

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

Provisional restorations are beneficial to final restorations. However, the importance of provisional restorations is often overlooked because they are designed to function for a limited period. This article summarizes the clinical values and two common materials of provisional restorations.

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

Objective: To clinically evaluate the bleaching effect, tooth sensitivity and rebound effect (3-month follow-up) of combined bleaching technique and deep bleaching technique. Methods: 30 Patients were recruited according to inclusion and exclusion criteria. Both two dental bleaching techniques, included in-office bleaching followed by at-home bleaching, and at-home bleaching followed by in-office bleaching and at-home bleaching, which were called combined bleaching technique and deep bleaching technique, respectively, were performed in the same mouth in each subject. All subjects received at-home bleaching with 6% hydrogen peroxide (HP) for 1 h/d within 7 days on one side of the dental arch (15 on the left side and the other on the right side), and followed by three 8-minute in-office bleaching treatments in succession with 35% HP on the maxillary anterior teeth, and finally with identical at-home bleaching on the maxillary anterior teeth. Tooth color was objectively evaluated using Olympus Crystaleye Spectrophotometer at the baseline appointment, and 1st, 7th, 30th and 90th day after treatment. The soft tissues and sensitivity of gingival and hard tooth tissues were evaluated using Loe and Silness Gingival Index and Visual Analog Scale (VAS) at baseline, 1st and 7th day after treatment. Results : Significantly less prominent color change and tooth sensitivity were observed in teeth received combined bleaching technique, compared with those received deep bleaching technique (P < 0.05). There was no significant difference in color rebound effect between the two bleaching techniques (P > 0.05). Conclusions Both combined bleaching technique and deep bleaching technique show satisfactory effects and the same rebound effect during the same periods of follow-up. Deep bleaching technique is a more effective method of bleaching, however, with high frequency of tooth sensitivity.