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Hepcidin is one of the most important proteins in iron metabolism. In the present study, its role in iron metabolism and the associated signaling pathways involved was investigated in a mouse model with insulin receptor substrate 1-loss of function (IRS-/-), and osteoblasts in the iron overload condition. Protein expression levels of hepcidin, interleukin 6 (IL-6), bone morphogenetic protein receptor 1a and ferritin demonstrated a significant increase in the liver of the IRS-/- mice compared with the IRS+/- and IRS+/+ mice. Hepcidin levels in the jaw bone were also increased in the IRS-/- mice (although not significantly). Furthermore, mRNA expression levels of bone morphogenetic protein 6 (BMP6) and ferroportin (FPN) were significantly increased in the liver of the IRS-/- mice compared with the other two models, but no significant differences were observed in the transferrin receptor mRNA expression levels. Additionally, the mRNA expression of hepcidin, FPN and IL-6 was upregulated in osteoblasts after ferric ammonium citrate exposure, while the mRNA expression of BMP6 was inhibited. Collectively, the results of the present study indicated that hepcidin is involved in iron metabolism in IRS-1-/- mice via the signaling pathways involving BMP6 and IL-6. Furthermore, hepcidin is also involved in iron metabolism in osteoblasts under iron overload conditions. Therefore, hepcidin and its associated signaling pathway proteins may represent potential targets for the treatment of conditions associated with iron overload. [ABSTRACT FROM AUTHOR]

Objective To study whether SiO2 films will influence the color of Ni-Cr metal ceramic restorations. Methods For the film plating experimental group, Sol--gel method was employed to apply SiO2 films to the surface of the Ni-Cr copings, while no coating was applied for the non-film-plating control group. Veneering porcelains were then applied subsequently, and a total of 12 B2-colored maxillary incisor metal ceramic crowns were fabricated with 6 crowns in each group. A ShadeEye Ncc computer-aided colorimeter was employed to measure the shade of the samples, as well as 6 B2(Vitapan classical vita color tabs) shade standards. The color was expressed as CIE-1976-Lab coordinates. Results There was a statistically significant color difference between all metal ceramic crowns and the B2 shade standards (ΔE>1.5). The L*, a*, b* values of all crowns were higher than those of the B2 shade standards, and the crowns were typically yellower or redder. While neither significant color difference nor difference in shade values was observed between the film plating experimental group and non-film-plating control group (ΔE< 1.5). Conclusion SiO2 films applied to the Ni-Cr copings by means of Sol-gel technique do not impact the final color of the metal ceramic restorations. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effects of a bleaching gel and a whitening strip on the microleakage of three different glass-ionomer cements. Methods Forty-five freshly extracted human premolars were used and class V cavity was prepared on the buccal and lingual surfaces. The teeth were randomly assigned to A, B and C groups and restored as follows: Conventional strengthen glass -ionomer cement (Ketac™ Molar Easymix), compomer (F2000) and compomer (Dyract AP). Teeth were kept in distilled water at 37 °C for 7 days. Then the specimens were thermocycled for 500 times. Each group was randomly divided into 3 subgroups which were treated for 21 days with one of the following: Whitening strip (14% hydrogen peroxide), bleaching gel (10% carbamide peroxide), or distilled water (control). After bleaching, the teeth were placed in a solution of basic fuchsin dye for 24 hours, then the teeth were sectioned longitudinally to evaluate the dye penetration. The depth of staining along the tooth restoration interface was recorded with a stereomicroscope. Results There were no signicant differences between the two bleaching agents in microleakage of restorations (I~0.05). The two bleaching agents did not significantly affect the microleakage of compomer (P>0.05), whereas the microleakage of glass-ionomer cement in the experimental groups was higher than that in the control group (P<0.05). Conclusion There are no significant differences in microleakage of restorations between bleaching gel (10% carbamide peroxide) and whitening strip (14% hydrogen peroxide). The two bleaching agents do not significantly affect the microleakage of compomer but adversely affect the microleakage of strengthen glass-ionomer cement. [ABSTRACT FROM AUTHOR]

Objective: To explore the remineralization effect of bioactive glass NovaMin on demineralized dentin specimens, and to study the physical and chemical properties of formed structure at dentin surface.
 Methods: One mm-thickness coronal dentin slices were soaked in ethylene diamine tetraacetic acid (EDTA) for 48 h to prepare the completely demineralized dentin specimens and they were divided into 2 groups: an artificial saliva group (control group) and a NovaMin powder group. The specimens were treated with artificial saliva or NovaMin powder for 2 min (2 times every day), and the interval was 8 hours. Then, the specimens were soaked in the remineralization solution. After 7 days, the scanning electron microscope (SEM), energy dispersive X-ray (EDX), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD) were used to detect dentin morphology, the physical and chemical properties of the formed structure at dentin surface.
 Results: The results of SEM showed that a defined surface layer in the NovaMin powder group could be observed in the SEM imaging at the 7th day, which completely occluded dentinal tubules; the EDX, ATR-FTIR and XRD analysis found that the mineralized layer formed at dentin surface was mainly composed of calcium and phosphate elements, which was similar to the hydroxyapatite-like crystal. However, there were no materials formed at the dentin surface in the control group, and the dentinal tubules were still open.
 Conclusion: NovaMin can remineralize the demineralized dentin specimens and occlude the dentinal tubules in hydroxyapatite-like crystal structure.

Purpose: To investigate the effects of desensitizing agents on dentin tubule occlusion, acid and tooth brushing challenge, and microhardness change of human dentin., Methods: Partially demineralized dentin slabs were divided into four groups (n = 30): (1) Control, (2) Non-desensitizing toothpaste, (3) Pro-Argin toothpaste, (4) CPP-ACP paste. The specimens were treated with these dentifrices for 2 minutes/day and soaked in artificial saliva (AS) for 24-hour remineralization. Then the dentin discs were divided into three subgroups for removal resistance tests: acid challenge, mechanical brushing challenge and blank control. Changes in dentin morphology were observed using scanning electron microscopy (SEM). Vickers microhardness measurements were performed at baseline and after 24-hour remineralization for all groups., Results: A surface layer and intra-tubular crystals were observed in SEM imaging of Pro-Argin toothpaste and CPP-ACP paste groups, which occluded most of the dentin tubules for those specimens. But the dentin tubules were opened after the acid challenge again. Moreover, the dentin microhardness showed a slight increase after 24-hour AS immersion. The percentage microhardness gain (PMG) values of these two groups were 5.4% and 5.1% respectively, which were significantly higher than the other groups (P < 0.05).

Objective: To evaluate the effects of a bleaching gel and a whitening strip on the microleakage of three different glass-ionomer cements., Methods: Forty-five freshly extracted human premolars were used and class V cavity was prepared on the buccal and lingual surfaces. The teeth were randomly assigned to A, B and C groups and restored as follows: Conventional strengthen glass-ionomer cement (Ketac Molar Easymix), compomer (F2000) and compomer (Dyract AP). Teeth were kept in distilled water at 37 degrees C for 7 days. Then the specimens were thermocycled for 500 times. Each group was randomly divided into 3 subgroups which were treated for 21 days with one of the following: Whitening strip (14% hydrogen peroxide), bleaching gel (10% carbamide peroxide), or distilled water (control). After bleaching, the teeth were placed in a solution of basic fuchsin dye for 24 hours, then the teeth were sectioned longitudinally to evaluate the dye penetration. The depth of staining along the tooth restoration interface was recorded with a stereomicroscope., Results: There were no signicant differences between the two bleaching agents in microleakage of restorations (P>0.05). The two bleaching agents did not significantly affect the microleakage of compomer (P>0.05), whereas the microleakage of glass-ionomer cement in the experimental groups was higher than that in the control group (P<0.05)., Conclusion: There are no significant differences in microleakage of restorations between bleaching gel (10% carbamide peroxide) and whitening strip (14% hydrogen peroxide). The two bleaching agents do not significantly affect the microleakage of compomer but adversely affect the microleakage of strengthen glass-ionomer cement.

Objective: To determine the expression levels of EphA7 and MTDH and detect their clinicopathological significance in the peritumoral normal tissues and the squamous cell cancer of the tongue., Methods: Envision immunohistochemistry was used to assay the expression levels of EphA7 and MTDH in the conventional paraffin-embedded sections from specimens of squamous cell cancer (n=45) and peritumoral normal tissues (n=10)., Results: The positIVe rates of EphA7 and MTDH were significantly higher in the squamous cell cancer than those in the peritumoral normal tissues ( χ(2)(EphA7)=4.14; χ(2)(MTDH)= 5.25; P < 0.05). The positIVe rates of EphA7 and MTDH expression were significantly lower in the cases of histological grade I-II,clinical stage I-II, and no-metastasis of neck lymph node than those in the histological grade III-IV, clinical stage III-IV, and metastasis of neck lymph node (P <0.05 or P <0.01)., Conclusion: The expression levels of EphA7 and/or MTDH might have important effect on the carcinogenesis and progression of tongue cancer. Overexpression of EphA7 and/or MTDH might have poor prognosis.

Objective: To study whether SiO2 films will influence the color of Ni-Cr metal ceramic restorations., Methods: For the film plating experimental group, Sol-gel method was employed to apply SiO2 films to the surface of the Ni-Cr copings, while no coating was applied for the non-film-plating control group. Veneering porcelains were then applied subsequently, and a total of 12 B2-colored maxillary incisor metal ceramic crowns were fabricated with 6 crowns in each group. A ShadeEye Ncc computer-aided colorimeter was employed to measure the shade of the samples, as well as 6 B2(Vitapan classical vita color tabs) shade standards. The color was expressed as C1E-1976-Lab coordinates., Results: There was a statistically significant color difference between all metal ceramic crowns and the B2 shade standards (delta E>1.5). The L*, a*, b* values of all crowns were higher than those of the B2 shade standards, and the crowns were typically yellower or redder. While neither significant color difference nor difference in shade values was observed between the film plating experimental group and non-film-plating control group (delta E<1.5)., Conclusion: SiO2 films applied to the Ni-Cr copings by means of Sol-gel technique do not impact the final color of the metal ceramic restorations.

Objective: To investigate the effects of cyclosporin A (CSA) on the level of intercellular adhesion molecule-1 (ICAM-1) expressed by oral fibroblasts (FB)., Methods: The fibroblasts were obtained from normal buccal mucosa (NM-FB) and cultured in vitro. Then the levels of ICAM-1 expressed by fibroblasts incubated with or without CSA in the presence of 10% fetal calf serum for 48 hours at 37 degrees C in 5% CO(2) and air were monitored by using cell-based ELISA for ICAM-1., Results: We demonstrated that NM-FB had ICAM-1 expression (A = 0.324 +/- 0.030), and after 48 hours incubated with CSA the ICAM-1 levels expressed by oral buccal mucosa fibroblasts were dose-dependently decreased., Conclusions: CSA reduces the levels of ICAM-1 expressed by oral mucosal FB, and may be useful in the treatment of some oral mucosal disorders.