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Article in Chinese | WPRIM | ID: wpr-823513


Objective To analyze the influence of a dental caries phototherapy device using neodymium-yttrium-aluminum-garnet (Nd:YAG) laser on the temperature of tooth pulp chamber of different sites and morphologies under different irradiation duration and power. Methods Fifty intact isolated teeth were collected and randomly divided into middle incisor group, upper right first premolar group, upper right second molar group, upper left first premolar group, and upper left second molar group. Each experimental group was irradiated according to the laser power 1.5, 1.6, 1.7, 1.8, 1.9 and 2.0 W, and the irradiation duration 30, 60, 90 s. The temperature rise of the pulp chamber was recorded with a thermocouple thermometer. Results After the laser irradiation, the temperature of the tooth pulp chamber increased, and the temperature rise was less than 5.5℃, i.e. the threshold leading to the dental pulp necrosis. Conclusions The use of laser to prevent dental caries will increase the temperature of the tooth pulp chamber, but the temperature rise in the range of 5.5 ° C is relatively safe and will not cause irreversible damage to the pulp tissue.

Article in Chinese | WPRIM | ID: wpr-693103


Objective To compare the pulp chamber temperature changes of Nd:YAP laser, Nd:YAG laser and semiconductor laser with the same power during dentin hypersensitivity treatment, and to evaluate the safety of these three laser treatments for dentin hypersensitivity. Methods 50 intact third molars were collected to prepare the dentin hypersensitivity model. The samples were randomly divided into Nd:YAP laser group (n=15), Nd:YAG laser group (n=15), semiconductor laser group (n=15), and blank control group (n=5). Each experimental group was divided into three subgroups (n=5) of 0.9 W, 1.4 W, and 1.8 W according to the laser power. The experiments were conducted with the corresponding laser parameters and thermocouple thermometer was used to record the temperature changes in the pulp chamber. The control group does not do any processing. After laser irradiation, one sample was randomly taken from each group and the morphology of dentin tubules was observed by scanning electron microscopy. Results When different power lasers were used to irradiate the samples, the temperatures of the pulp chamber in each group were increased. Among them, the temperature rise of the pulp chamber was smallest in the Nd:YAP laser group, followed by the semiconductor laser group, and the temperature rise was highest in the Nd:YAG laser group, but it was still lower than 5.5 ° C that could cause pulp necrosis. Scanning electron microscopy results showed that after irradiation with different power lasers, the diameters of most dentinal tubules in the Nd:YAG laser group and the semiconductor laser group were narrowed or even melted, and the effect was better than that of the Nd:YAP laser group. Conclusion The treatment using Nd:YAP laser, Nd:YAG laser and semiconductor laser for dentin hypersensitivity will increase the temperature of the pulp chamber. However, the temperature rise is less than 5.5℃and that will not cause irreversible damage to the pulp tissue. Nd:YAG laser and semiconductor laser have better dentinal tubule blocking effect, which is more suitable for laser dentin desensitization treatment than Nd:YAP laser.

Chinese Journal of Hepatology ; (12): 354-357, 2014.
Article in Chinese | WPRIM | ID: wpr-314044


<p><b>OBJECTIVE</b>To explore the effect of silencing the Notch2 gene by small interfering (si)RNA on the proliferation of the HepG2 human hepatocellular carcinoma (HCC) cells.</p><p><b>METHODS</b>Notch2-siRNA was transfected as a liposomal formulation into HepG2 cells. The non-HCC cell lines SG07901 (gastric cancer) and SW620 (colon cancer) were used as controls. The mRNA expression of Notch2 and Hesl were detected by RTPCR, and the protein expression of Notch2 was detected by western blotting. The proliferation of transfected HepG2 cells was assessed by the cell counting kit-8 (CCK8) colorimetric assay.</p><p><b>RESULTS</b>The untransfected HepG2 cells showed significantly upregulated transcript expression of Notch2, and not of Notch1, Notch3 or Notch4, compared to the other non-HCC cell lines. Following transfection of Noteh2-siRNA into HepG2 cells, the mRNA expression of Notch2 and Hes1 and the protein expression of Notch2 were significantly decreased. The rales of proliferation inhibition in HepG2 following transfection of Notch2-siRNA showed an increasing time-related trend, with 2.64% ± 1620% at 12 h, 38.34% ± 8.80% at 24 h, 70.05% ± 7.80% at 48 h, 70.78% ± 10.00% at 72 h, and 74.22% ± 4.80% at 96 h.The inhibition rate at 24 h of transfection was significantly different from that of the groups of control cells.</p><p><b>CONCLUSION</b>Notch2 is upregulated in the common HCC cultured cell line HepG2. siRNA-mediated silencing of Notch2 exerts inhibition effects on HepG2 proliferation, suggesting the potential for this approach as targeted therapy for treating HCC.</p>

Carcinoma, Hepatocellular , Pathology , Cell Proliferation , Down-Regulation , Hep G2 Cells , Humans , Liver Neoplasms , Pathology , RNA Interference , RNA, Small Interfering , Receptor, Notch2 , Metabolism
Article in Chinese | WPRIM | ID: wpr-438891


Objective To comparatively analyze the immunological characteristics of patients with mild and severe influenza A (H1N1), and to provide the evidence for condition monitoring and treatment . Methods 52 cases with mild influenza A ( H1N1), 152 cases with severe influenza A ( H1N1) and 26 healthy subjects from July 1, 2009 to December 31, 2009 were enrolled in the study.Lymphocyte subsets in peripheral blood were analyzed by flow cytometry and the serum concentrations of interferon -γ( IFN-γ) and interleukin-4 (IL-4) were detected by enzyme-linked immune-sorbent assay (ELISA).Results The total lymphocyte counts were decreased obviously in patients with severe influenza A ( H1N1) than in mild pa-tients and in healthy subjects (P0.05).Con-clusion Immune dysfunction in patients with influenza A (H1N1) infection is associated with the severity of disease, especially cellular immunity .Therefore, monitoring of the immune system is valuable for the diag-nosis of influenza A(H1N1) infection.

Article in Chinese | WPRIM | ID: wpr-529402


AIM:The aim of this study was to examine the microstatellite instability(MSI)and loss of heterozygosity(LOH)of locus D17S396 on chromosome 17 and their influence on the expression of nm23H1 in hepatocellular carcinoma(HCC),which may provide experimental evidence for the mechanism of nm23H1 gene and tumor metastasis.METHODS:Techniques such as DNA extraction from formalin-fixed paraffin-embedded tissues,PCR-SSCP,ordinary silver stain were used to study MSI and LOH of locus D17S396.Envision immunohistochemistry and Leica-Qwin computer imaging techniques were used to assess the expression of nm23H1.RESULTS:① The frequency of heredity instability of HCCs was 35.42%.The frequency of LOH in the cases with lymph node or distant organs metastasis or not and with intrahepatic metastasis or embolus of portal vein or not was significantly different(P

Article in Chinese | WPRIM | ID: wpr-526886


AIM: To evaluate the specific cellular immune response in mice inoculated with the recombinant hepatitis B virus (HBV) surface vaccine (rHBs). METHODS: Spleen T lymphocyte reactivity to rHBs was assessed by a proliferation assay and cytokine secretion. BALB/c mouse were intraperitoneally inoculated with rHBs at doses of 0.65, 1.25, 2.5 or 5 ?g for once or twice. 4 weeks later, spleen lymphocytes were harvested and restimulated with rHBs in experimental group or with PBS as control. The spleen lymphocytes were labeled with [~3H]-thymidine for 3 days. The [~3H]-thymidine incorporation was measured, which expressed as the incorporation of [~3H] (counts?min~ -1 ) and stimulation index (SI) was calculated by the method of dividing the cpm obtained in the experimental group by that in control group. The content of IL-2 and IFN-? secreted from the spleen lymphocyte were measured by the method of ELISA. RESULTS: 2 weeks after primary vaccination, the SI in 0.65, 1.25, 2.5 and 5 groups was 1.55, 1.93, 2.41, 2.81 ng/L, respectively. IL-2 was 5.48?8.88, 9.28?6.98, 28.53?14.32, 64.69?20.88 ng/L, respectively. IFN-? was 8.22?8.61, 9.89?9.34, 20.27?15.50, 30.77?22.12 ng/L, respectively. 2 weeks after boost vaccination, the SI in 0.65, 1.25, 2.5 and 5 groups was 1.61, 2.05, 3.74, 3.62 ng/L, respectively. The IL-2 was 5.75?5.04, 102.53?67.52, 177.13?91.12, 332.10?124.31 ng/L, respectively. IFN-? was 3.63?4.42, 28.33?13.04, 59.66?25.75, 80.73?19.30 ng/L, respectively. CONCLUSION: Specific proliferation activity and IL-2, IFN-? secretion from the spleen lymphocytes of the mouse inoculated with rHBs are produced,that the strength is dependent on the dose of vaccination.