Objective: To investigate the effect of permeable resin on the surface structure, microhardness and color of tooth enamel after bleaching. Methods: Premolars extracted for orthodontic needs were selected (provided by the Department of Oral and Maxillofacial surgery of the first affiliated Hospital of Zhengzhou University) and randomly divided into A, B and C 3 groups. Each group was randomly divided into control subgroup, resin subgroup, bleaching subgroup and combined subgroup. Samples in the control subgroup did not receive any treatment. Those in the bleaching subgroup and combined subgroup were treated with cold light whitening. Those in the resin group and combined group were treated with permeable resin. Samples in the group A were observed by scanning electron microscope immediately after treatment and 2 weeks after treatment, and the microhardness of samples in the group B was measured before treatment, immediately after treatment and 2 weeks after treatment (the sample size of each time point was 8 in each subgroup). In group C, chromaticity was measured and chromatic aberration (ΔE value) was calculated before treatment, immediately after treatment and 1 and 2 weeks after treatment (10 samples in each subgroup). Results: Scanning electron microscope showed that the enamel surface of the resin subgroup and the combined group was smooth immediately after treatment, which was basically the same as that of the control subgroup, but covered with resin, and microporous defects and mineral deposits could be seen on the surface of the bleaching subgroup. Two weeks after treatment, the enamel surface of each subgroup was smooth, there was no obvious difference. Immediately after treatment, the microhardness of the control subgroup, resin subgroup, bleaching subgroup and combined subgroup were (354±33), (364±21), (411±30) and (350±17) HV, respectively (F=9.39,P<0.05). The microhardness of the bleaching subgroup was significantly higher than that of the other subgroups (P<0.05). There was no significant difference in microhardness among the four subgroups before treatment and 2 weeks after treatment (F=0.34, 2.75, P>0.05). Immediately after treatment, the ΔE values of the control subgroup, resin subgroup, bleaching subgroup and combined subgroup were 0.00±0.00, 2.29±1.86, 7.20±1.94 and 8.00±0.88, respectively (F=74.21,P<0.05); except that there was no significant difference between bleaching subgroup and combined subgroup (P>0.05), there were significant differences among the other subgroups (P<0.05). There was no significant difference in ΔE value among control subgroup, resin subgroup and bleaching subgroup at each time point (F=1.66, 0.30, 0.96, P>0.05). The difference in the combined subgroup immediately after treatment was significantly higher than that at 1 and 2 weeks after treatment (t=4.73, 4.23,P<0.05), but there was no significant difference between 1 and 2 weeks after treatment (t=0.75, P>0.05), and the color tended to be stable. Conclusions: When whitening healthy enamel, simple cold light whitening or cold light whitening combined with permeation resin can achieve whitening effect.
Color ; Dental Enamel ; Hardness ; Humans ; Hydrogen Peroxide/pharmacology* ; Tooth Bleaching/adverse effects* ; Tooth Bleaching Agents/pharmacology*

BACKGROUNDCigarette smoke induced airway inflammation plays a role in pathogenesis of airway inflammation. Resolvin-D1 derived from omega-3 polyunsaturated fatty acids is an endogenous anti-inflammatory and proresolving lipid mediator. Resolvin-D1 ameliorated inflammatory responses in lung injury, asthma, peritonitis and atherosclerosis. We investigated whether resolvin-D1 suppressed the productions of chemokines and oxidative stress induced by cigarette smoke extract (CSE) in vitro and its possible mechanism.

METHODSWe examined the proinflammatory chemokine interleukin-8 and hydrogen peroxide (H2O2) productions induced by CSE in 16 human bronchial epithelial (16HBE) cells after resolvin-D1 treatment and their mechanisms. 16HBE cells were treated with resolvin-D1 at up to 10 nmol/L, for 30 minutes before CSE up to 16% (v/v) exposure. Release of interlukin-8 proteins was assessed by enzyme linked immunosort assay (ELISA) and its mRNA level by RT-PCR. We evaluated extracellular H2O2 expression in the supernatant. Phosphorylation of NF-κB/p65 and degradation of I-κB in 16HBE cells were determined by Western blotting analysis and NF-κB DNA binding activity by electrophoretic mobility shift assay (EMSA).

RESULTS16HBE cells treated with 8% CSE showed significantly higher interlukin-8 production. Resolvin-D1 pretreatment inhibited CSE induced interlukin-8 production (mRNA and protein) in a dose and time dependent manner. Extracellular H2O2 level decreased after resolvin-D1 treatment. Resolvin-D1 attenuated CSE triggered I-κB degradation and NF-κB/p65 activation dose dependently and inhibited NF-κB DNA binding activity.

CONCLUSIONResolvin-D1 inhibits CSE induced interlukin-8 and H2O2 production in 16HBE cells by modulating NF-κB activation and has therapeutic potential for pulmonary inflammation.

Blotting, Western ; Cell Line ; Cell Survival ; drug effects ; Docosahexaenoic Acids ; pharmacology ; Electrophoretic Mobility Shift Assay ; Enzyme-Linked Immunosorbent Assay ; Humans ; Hydrogen Peroxide ; metabolism ; Interleukin-8 ; metabolism ; NF-kappa B ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Smoking ; adverse effects

OBJECTIVETo investigate the role of Fas pathway in H(2)O(2)-induced apoptosis of L02 human hepatocytes and the effect of schisandrin B on Fas pathway.

METHODSReal-time quantitative PCR was used to detect the expressions of FAS, fas associated death domain protein (FADD) and caspase-8 mRNA in L02 cells exposed to H(2)O(2). Flow cytometry was employed to assess the cell apoptosis. ELISA, Western blotting and spectrophotometric assay were performed to determine the expressions of FAS protein, FADD protein and caspase-8 activity.

RESULTSWithin the dose range of 5-15 mol/L, schisandrin B dose-dependently inhibited FAS and FADD expressions and caspase-8 activation.

CONCLUSIONSchisandrin B can partially inhibit H(2)O(2)-induced L02 cell apoptosis possibly by affecting the FAS-FADD-caspase-8 pathway.

Apoptosis ; drug effects ; Caspase 8 ; metabolism ; Cell Line ; Cyclooctanes ; pharmacology ; Fas-Associated Death Domain Protein ; metabolism ; Flow Cytometry ; Hepatocytes ; drug effects ; metabolism ; Humans ; Hydrogen Peroxide ; adverse effects ; Lignans ; pharmacology ; Polycyclic Compounds ; pharmacology ; Signal Transduction ; fas Receptor ; metabolism

OBJECTIVETo study the effects of ecdysterone (ECR) on the expression of nuclear factor (NF)-kappaB in H2O2 induced oxidative damage of human lens epithelial cells (HLECs).

METHODSThe cultured HLECs were divided into 5 groups, i.e., the control group, the H2O2 group, the beta-estradiol (E2) group, the ECR group, and the pyrrolidine dithiocarbamate group (PDTC) group. The expression rate of NF-kappaB p65 in the HLECs were detected by flow cytometer (FCM).

RESULTSThe expression of NF-kappaB p65 occurred in normal HLECs (9. 53%). The expression rate of NF-kappaB p65 in the H2O2 group obviously increased (39.87%, P < 0.01). The expression rate of NF-kappaB p65 in the PDTC group obviously decreased (5.90%, P < 0.01). The expression rates of NF-kappaB p65 in the ECR group (13.99%) and the E2 group (25.18%) ranged between the control group and the H2O2 group, but still lower than that of the H2O2 group (P < 0.01).

CONCLUSIONSThe activation of NF-kappaB in the HLECs could be induced by H2O2 ECR with the estrogenic activity could effectively inhibit the activation of NF-kappaB.

Cells, Cultured ; Ecdysterone ; pharmacology ; Epithelial Cells ; drug effects ; metabolism ; Humans ; Hydrogen Peroxide ; adverse effects ; Lens, Crystalline ; cytology ; Oxidative Stress ; drug effects ; Transcription Factor RelA ; metabolism

OBJECTIVETo study the effects of Guanxinping Tablet (GT) containing serum on H2O2-induced apoptosis and the nuclear factor kappa B (NF-kappaB) expression in vascular endothelial cells (VECs).

METHODSRabbits were randomly divided into the normal control group (treated with normal saline, 10 mL/kg), the verapamil group (0. 02 g/kg, 10 mL/kg), the small dose GT group (2; 8 g/kg, 10 mL/kg), the middle dose GT group (5.6 g/kg, 10 mL/kg), and the large dose GT group (11.2 g/kg, 10 mL/kg), 3 in each group. The medication was given to rabbits by gastrogavage for 3 successive days. The gastrogavage was performed twice on the last day with an interval of 2 h. One h after the last medication the peripheral blood was sampled from the vein of the ear edge. The blood was put for 1 h and centrifuged at 2 500 r/min for 30 min. The serum was extracted and deactivated at 56 degrees C for 30 min to prepare the drug containing serum. The apoptosis injury model was established using 100 micromol/L H2O2 induced VECs in the log phase growth. After modeling they were divided into 6 groups, 5 samples in each group, i. e., the normal group (10% vehicle serum culture solution), the model group (10% vehicle serum culture solution +100 micromol/L H2O2), the verapamil group (10% verapamil serum culture solution +100 micromol/L H2O2), the low dose GT group (10% low dose GT culture solution +100 micromol/L H2O2), the middle dose GT group (10% middle dose GT culture solution + 100 micromol/L H2O2), and the high dose GT group (10% high dose GT culture solution + 100 micromol/L H2O2). THE VEC apoptotic rate was detected using flow cytometry. The protein expression of NF-kappaB was detected using Western blot.

RESULTSThe VEC apoptosis rate (9.00% +/- 1.18%) and the protein expression of NF-kappaB (0.39% +/- 0.06%) increased more in the model group than in the normal control group (P<0.01). Compared with the model group, the VEC apoptosis rate of the verapamil group (6.00% +/- 0.18%), the large dose GT group (5.30% +/- 0.08%), and the middle dose GT group (6.83% +/- 0.51%) were obviously lower. The expression of NF-kappaB of each treatment group significantly decreased (the verapamil group: 0.28% +/- 0.03%; the small dose GT group: 0.33% +/- 0.03%; the middle dose GT group: 0.30% +/- 0.03%; the large dose GT group: 0.28% +/- 0.04%, P<0.01, P<0.05).

CONCLUSIONSGT could fight against H2O2-induced VEC cell apoptosis. Its mechanism might be correlated with regulating the expression of NF-kappaB protein.

Animals ; Apoptosis ; drug effects ; Cells, Cultured ; Drugs, Chinese Herbal ; pharmacology ; Endothelial Cells ; cytology ; metabolism ; Humans ; Hydrogen Peroxide ; adverse effects ; Male ; NF-kappa B ; metabolism ; Rabbits ; Serum

OBJECTIVEOn basis of preliminary studies, to prepare the effective components group of Xiaoxuming decoction for anti-ischemic by combining chemical analysis with pharmacological activity screening.

METHODFree radical scavenging was assayed by DPPH method; the cell viability injured by hydrogen peroxide, L-glutamate, and hypoxia was determined by MTT assay; TBA method was used to determine mitochondrial lipid peroxidation.

RESULTComprehensive analysis of multi-target results, the comprehensive activities of 40% ethanol elution and the middle layer were the highest.

CONCLUSION40% ethanol elution and the middle layer were proportionally mixed as the effective components group of Xiaoxuming decoction.

Animals ; Brain ; blood supply ; drug effects ; metabolism ; Cell Survival ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Free Radical Scavengers ; pharmacology ; therapeutic use ; Glutamic Acid ; adverse effects ; Hydrogen Peroxide ; adverse effects ; Ischemia ; drug therapy ; metabolism ; Male ; Mitochondria ; drug effects ; metabolism ; PC12 Cells ; Rats ; Rats, Wistar

Hydrogen peroxide is commonly used as a disinfectant that has been reported to cause chemical colitis. We report a case of 49 year-old man who presented with chemical colitis caused by self-inflicted hydrogen peroxide enema. In the sigmoidoscopic examination, diffuse erythematous and edematous mucosal change with multiple ulcerations and easy touch bleeding was noted from the rectum to the proximal sigmoid colon. Abdominal computed tomography showed diffuse wall thickening of the rectum and the sigmoid colon with inflammatory and reactive change at surrounding. The patient was treated with NPO, intravenous fluid, and antibiotic therapy. On 5th hospital day, abdominal pain and bloody stool disappeared, and the patient started oral feeding. He discharged on 6th hospital day with fully recovered state.
Abdominal Pain/etiology ; Colitis/*chemically induced/therapy ; Enema/*adverse effects ; Gastrointestinal Hemorrhage/etiology ; Humans ; Hydrogen Peroxide/*adverse effects ; Male ; Middle Aged ; Sigmoidoscopy ; Tomography, X-Ray Computed

The aim of this study was to explore the protective effect of compound tianpupian (TPP) against (2)O(2)-induced the apoptosis of murine splenic lymphocytes and its mechanism. The cell apoptosis rate was detected by MTT method; the cell apoptosis and mitochondrial membrance potential were detected by flow cytometry (FCM) with Annexi-V/PI double staining and JC-1 staining method, respectively; and caspase 3 relative activity was determined by colorimetry. The results indicated that after treating with (2)O(2), the absorbance value of cultured lymphocytes and the red/green ratio of JC-1 were reduced, and the apoptotic rate and caspase 3 activity were increased, coculture of (2)O(2)-treated cells with compound TPP increased the cell absorbance ratio and red/green rate of JC-1, while reduced the apoptosis rate and caspase 3 activity. It is concluded that compound TPP alleviates intracellular oxidative damages and dose-dependently inhibited apoptosis of murine splenic lymphocytes through reducing mitochondrial membrane potential and inhibiting caspase 3 activity. This suggests that compound TPP is a potential anti-apoptotic agent.
Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Grape Seed Extract ; pharmacology ; Hydrogen Peroxide ; adverse effects ; Lymphocyte Count ; Lymphocytes ; cytology ; drug effects ; Mice ; Mice, Inbred ICR ; Proanthocyanidins ; pharmacology ; Rhodiola

AIMTo investigate the antioxidant effects of Morinda officinalis (Morindae radix, MR) on H(2)O(2)-induced oxidative stress in cultured mouse TM3 Leydig cells.

METHODSWe carried out 2,2-diphenyl-1-picrylhydrazyl free radical scavenging, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, lipid peroxidation, testosterone enzyme immunoassay, superoxide dismutase (SOD), and catalase (CAT) assays in Leydig TM3 cells.

RESULTSMR showed a 47.8% 2,2-diphenyl-1-picrylhydrazyl radical scavenging effect in TM3 cells with no significant cytotoxicity. Oxidative stress was induced in TM3 cells with 100 micromol H(2)O(2), and treatment of the cells with 250 microg/mL MR showed the most significant protective effect (64%, P < 0.001) in the cell viability assay with a decreased lipid peroxidation level (1.75 nmol/mg protein, P < 0.05), increased testosterone production (43.5 pg/mL), and improvements in SOD activity (7.49 units of SOD/mg protein, P < 0.001) and CAT activity (74.6 units of CAT/mg protein, P < 0.001).

CONCLUSIONThese findings indicate that MR, as an antioxidant, protects functions of cultured mouse TM3 Leydig cells from H(2)O(2)-induced oxidative stress.

Animals ; Catalase ; metabolism ; Cell Survival ; drug effects ; Cells, Cultured ; Hydrogen Peroxide ; adverse effects ; Leydig Cells ; cytology ; drug effects ; metabolism ; Lipid Peroxidation ; drug effects ; Male ; Mice ; Morinda ; Oxidative Stress ; drug effects ; Plant Extracts ; pharmacology ; RNA, Messenger ; metabolism ; Superoxide Dismutase ; metabolism ; Testosterone ; metabolism

OBJECTIVETo analyze the mechanisms of NAC on endoplasmic reticulum (ER) stress mediated cells apoptosis of HepG2 cells and to evaluate the potential role of NAC in the treatment of liver injury.

METHODSHepG2 cells were treated with H2O2 to make a model of oxidative ER stress mediated apoptosis. To evaluate the apoptosis, various methods such as MTT, DNA ladder, Western blot and flow cytometry were used. Then the optimal dosage and incubation time of NAC intervention in apoptosis were ascertained, and the differences between induction and intervention of apoptosis, including the percentage of apoptosis, the expression of apoptotic protein (GRP78, Caspase-12, PARP) and the production of reactive oxygen species (ROS) were compared.

RESULTSThe activity of the cells decreased by H2O2 (0, 1, 3, 5 mmol/L) treatments in a dose-dependent manner. The ratio of apoptotic cells increased (0.7%+/-0.5%, 26.4%+/-1.8%, 29.7%+/-1.2% and 51.2%+/-9.4%, respectively) as did the production of ROS (14.0%+/-0.5%, 95.2%+/-0.1%, 97.5%+/-0.2% and 98.3%+/-0.2%, respectively). The HepG2 cells showed typical morphologic change of ER stress 6 hr after they were treated with 3 mmol/L H2O2. ER stress mediated-apoptosis was confirmed by Western blot. NAC (10 mmol/L and 20 mmol/L) protected cells from apoptosis. Typical features of ER stress apoptosis were seen accompanied by diminishing the ratio of apoptotic cells from 29.7%+/-1.2% to 23.3%+/-4.7% and 14.3%+/-1.2%. The production of ROS also decreased from 97.5%+/-0.2% to 52.2%+/-0.8% and 51.2%+/-2.9%. The effect was related to the concentration: 20 mmol/L NAC was more effective than 10 mmol/L.

CONCLUSIONSAs an oxidizing agent, H2O2 may induce ROS in cells and induce oxidative stress, causing ER stress and apoptosis. NAC can inhibit the procession of ROS directly and prevent injuries to the hepatocytes.

Acetylcysteine ; pharmacology ; Apoptosis ; drug effects ; Endoplasmic Reticulum ; metabolism ; Hep G2 Cells ; Humans ; Hydrogen Peroxide ; Oxidative Stress ; Reactive Oxygen Species ; adverse effects