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Poly(ε-caprolactone) (PCL) is a promising material for tissue engineering applications; however, it can be difficult to create scaffolds with the morphology, hydrophilicity, and mechanical properties necessary to support tissue growth. Typically, pure PCL scaffolds have good cellular adhesion, but somewhat low mechanical properties (elastic modulus and tensile strength). This study addresses these issues by incorporating Al2O3 whiskers as reinforcements within PCL membranes generated by electrospinning. Membranes were prepared with Al2O3 content ranging from 1 to 20 wt % and characterized using XRD, TEM, and SEM to determine composition and morphology. The Al2O3 whiskers were well dispersed within the PCL fibers, and the membranes had a highly porous morphology. The elastic modulus was significantly improved by the well aligned whisker reinforcements as verified by tensile testing. The cell morphology and proliferation studies demonstrate Al2O3 whisker reinforced PCL scaffolds maintained the good biocompatibility. These improvements demonstrate that Al2O3 whisker reinforced PCL scaffolds can be considered as a biocompatible material for tissue engineering and dental applications. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2012. [ABSTRACT FROM AUTHOR]

Graphene quantum dots (GQDs) play a vital role in improving electrocatalytic activity during constructing various composites. Among them, heteroatoms‐doped GQDs can further improve the conductivity and electrocatalytic properties of the composites. Herein, NH2‐GQDs‐doped NiCo2O4, grown on carbon cloth, is developed through one‐step hydrothermal process. The NH2‐GQDs doping significantly enhances its electrochemical performance due to its high electron transfer rate and synergistic effects. Severing as freestanding electrochemical electrode, the NH2‐GQDs/NiCo2O4 composite on carbon cloth exhibits low detection limit of 0.27 × 10−6m and high sensitivity of 2521.33 µA mm−1 cm−2 for nonenzymatic determination of glucose. Furthermore, the fabricated glucose sensor shows outstanding selectivity and reproducibility. These results indicate that the NH2‐GQDs‐doped NiCo2O4 provides a convenient platform for nonenzymatic determination of glucose in the future. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effects of whitening toothpaste and bleaching with 6% hydrogen peroxide (H2O2) on discoloration of dental resin composite caused by cigarette smoke (CS) and electronic vapor product (EVP) aerosol., Methods: 40 resin composite discs were divided into three groups: 15 each for CS and EVP aerosol exposure and 10 for air exposure (control). Exposures were performed for 15 days, with daily brushing with regular toothpaste. Two whitening sessions, including 21 days of brushing with whitening toothpaste and 3 days of treatments with take-home bleaching (6% H2O2), were performed after the exposure. Color and gloss were assessed before exposure, at every 5 days of exposure, and after each whitening session., Results: After 15 days of exposure, marked discoloration of resin composite was observed in the CS group (ΔE = 23.66 ± 2.31), minimal color change in the EVP group ((ΔE = 2.77 ± 0.75), and no color change in the control group. Resin composites exposed to CS did not recover their original color after treatment with whitening toothpaste ((ΔE = 20.17 ± 2.68) or take-home bleaching ((ΔE = 19.32 ± 2.53), but those exposed to EVP aerosol reverted to baseline after treatment with whitening toothpaste ((ΔE = 0.98 ± 0.37), and no further change in color was observed following take-home bleaching. The gloss of resin composites exposed to CS, EVP aerosol, and air decreased equally with exposure time. Brushing with whitening toothpaste recovered the gloss similarly in all groups, but no further change was observed following take-home bleaching., Clinical Significance: Aerosol from electronic vapor products induced minimal discoloration of resin composites that can be completely reverted by brushing with whitening toothpaste alone. Bleaching with 6% H2O2 did not revert discoloration caused by cigarette smoke. Whitening toothpaste could help revert the decreased gloss of resin composites., Competing Interests: Dr. Zhao, Mr. Wang, Dr. Malmstrom and Dr. Ren declared no conflict of interest. Dr. Zanetti, Mr. Majeed, Dr. Hoeng, and Dr. Peitsch are employees of Philip Morris International. This study was funded in part by Philip Morris International., (Copyright©American Journal of Dentistry.)

Purpose: To study the mechanism of vascular endothelial growth factor (VEGF) regulated by miR-375 and Sonic hedgehog (SHH) signaling pathways on the characteristics of trophoblast cells (TCs) in preeclampsia (PE) rats., Methods: Female (100) Wistar rats in rut were mated with males (50) at a ratio of 2:1, and 60 pregnant rats were assigned to a normal group (Nor, n=10) and a model group (Mod, n=50) in a random manner. Rat TCs of placental villus were isolated and were divided into 8 groups. The related indicators in each group were detected, respectively., Results: In contrast to the NC group, miR-375 expression greatly elevated in the miR-375 mimic group (mimic group); in the mimic and cyclopamine groups, VEGF, proliferating cell nuclear antigen（PCNA, N- cadherin and Bcl-2 expression, cell proliferation, S phase cells, and migration and invasion ability were significantly decreased and E-cadherin and Bax expression, G1 phase cells and apoptosis rate were increased significantly, but in Over expressing-VEGF（ov-VEGF） group, the above indicators presented contrary results (all P< 0.05). In contrast to the mimic group, the expression of SHH, VEGF, PCNA, N- cadherin and Bcl-2, cell proliferation, S phase cells and the invasion and migration activity in the miR-375 mimic + oe-VEGF group were evidently increased., Conclusions: Over-expressing miR-375 can inhibit the expression of VEGF, thus slow down the invasion and proliferation of TCS in PE rats, which is realized by regulating SHH signal pathway., (Copyright 2020 The Author(s).)

Objectives: To test if cigarette smoke (CS) causes discoloration of enamel, dentin, and composite resin restorations and induces color mismatch between dental hard tissues and the restorations, and to compare the findings with the effects of aerosol generated by the tobacco heating system (THS) 2.2., Method and Materials: Twenty-two human premolars were prepared with Class V cavities restored with Filtek Supreme Ultra (3M Espe) composite resin. Teeth were divided into two groups and exposed to either CS from 20 reference cigarettes (3R4F) or aerosol from 20 THS 2.2 tobacco heat sticks 4 days a week for 3 weeks. CIE L*a*b* color was assessed before and after exposure and brushing at 1, 2, and 3 weeks. Color match, marginal discoloration, marginal integrity, and surface texture of the Class V restoration were assessed according to a modified US Public Health Service (USPHS) criterion., Results: Marked discoloration of enamel and dentin was observed following 3 weeks of CS exposure (ΔE = 8.8 ± 2.6 and 21.3 ± 4.4, respectively), and color mismatch occurred between the composite resin restorations (ΔE = 25.6 ± 3.8) and dental hard tissues. Discoloration was minimal in the enamel, dentin, and composite resin restorations in the THS 2.2 group, and no color mismatch was observed after 3 weeks of THS 2.2 aerosol exposure., Conclusion: CS causes significant tooth discoloration and induces color mismatch between dental hard tissues and composite resin restorations. Reducing or eliminating the deposits derived from tobacco combustion could minimize the impact of tobacco products on tooth discoloration.

Purpose: To study the effects of cigarette smoke (CS) on the discoloration of dental resin composite compared with the aerosol from a heat-not-burn tobacco product, the Tobacco Heating System 2.2 (THS2.2)., Methods: A total of 60 discs were prepared from three commercial resin composites: Durafill VS (DVS), Filtek Supreme Ultra (FSU) and Tetric EvoCeram BulkFill (TEC). Twenty discs of each composite were divided into two groups and exposed to CS from 20 reference cigarettes (3R4F) or aerosol from 20 THS2.2 tobacco sticks per day for 3 weeks. Color, gloss and surface roughness of the composite discs were measured at baseline and after exposure and brushing with toothpaste at 1, 2 and 3 weeks., Results: Color differences from the baseline (ΔE) were on average 27.1 (±3.6) in 3R4F and 3.9 (±1.5) in the THS2.2 group after 3 weeks of exposure (P< 0.0001). TEC (30.4±1.4 and FSU (28.0 ±2.5) exhibited more discoloration than DVS (23.0±1.2) in the 3R4F group (P< 0.0001). FSU (2.6 ±0.5) showed significantly less discoloration than TEC (5.3±1.5) in the THS2.2 group (P< 0.0001). Surface roughness of resin composites was not affected by either CS or THS2.2 aerosol, while surface gloss increased in the composite discs with more severe discoloration., Clinical Significance: Cigarette smoke caused significant discoloration of dental composite resins. Reducing or eliminating the deposits derived from combustion of tobacco has the potential to minimize the impact of smoking on the color of composite resin restorations., Competing Interests: Dr. Zanetti, Shoaib Majeed, Dr Peitsch and Dr. Hoeng are employed by Philip Morris International. Dr. Zhao, Dr. Pan, Dr. Malmstrom and Dr. Ren declared no conflict of interest. Dr. Zhao and Dr. Zanetti contributed equally to the study. The study was partially funded by Philip Morris International.

Objective: To investigate the expression of metastasis-associated in colon cancer-1 (MACC-1) mediated by siRNA, and to study the effects of its downregulation on cell proliferation, cell cycle and invasion ability of cervical cancer SiHa cells., Methods: MACC-1 siRNA and control siRNA were transfected into cervical cancer SiHa cells, and the expression of MACC-1 protein after transfection with MACC-1 siRNA was detected by Western blotting. The changes of cell proliferation, cell cycle and invasion ability of the SiHa cells were determined by CCK-8 kit, flow cytometry and Boyden chamber assay. The expressions of cell cycle- and invasion-related proteins were analyzed by Western blotting., Results: Compared with the untreated group (0.317 ± 0.023) and control siRNA group (0.309 ± 0.021), the expression of MACC-1 protein was downregulated in the MACC1 siRNA group (0.041 ± 0.006) (P < 0.05), and its downregulation significantly suppressed the cell proliferation, altered the cell cycle distribution and reduced the cell invasion ability of the SiHa cells (P < 0.05). Compared with the untreated group (0.217 ± 0.025 and 0.215 ± 0.024) and the control siRNA group (0.222 ± 0.023 and 0.207 ± 0.027), the expression of cyclin D1 and Cdk2 proteins were significantly decreased in the MACC1 siRNA group (0.076 ± 0.010 and 0.039 ± 0.007) (P < 0.05). Compared with the untreated group (0.099 ± 0.007) and control siRNA group (0.105 ± 0.012), the expression of p21 protein was significantly increased in the MACC1 siRNA group (0.676 ± 0.044) (P < 0.05). The downregulation of MACC-1 expression also evoked a decrease of expressions of MMP-2 and MMP-9 proteins and an increase of E-cadherin protein expression (P < 0.05)., Conclusions: MACC-1 downregulation-mediated inhibition of proliferation and decreased invasion ability of tumor cells may be closely associated with the alterations of expressions of cell cycle- and invasion-related proteins.

Objective: This study was conducted was to detect vascular endothelial growth factor (VEGF) levels in peripheral blood of patients with pregnancy-induced hypertension (PIH) syndrome and to investigate VEGF correlation with PIH occurrence., Methods: Double-antibody enzyme-linked immunosorbent assay and fluorescent quantitative polymerase chain reaction were used to detect VEGF levels in the peripheral blood of non-pregnant women (normal group, 30 cases), normal pregnant women (pregnancy group, 30 cases) and PIH patients (PIH group, 30 cases)., Results: VEGF level in the pregnancy group was significantly higher than in the normal group, and the difference between these two groups was significant (P < 0.001). In the pregnancy group, VEGF reached the maximum level at the metaphase stage of pregnancy and started to decrease at advanced pregnancy. VEGF level in the PIH group was significantly lower than in the pregnancy group at advanced pregnancy (P < 0.01), and VEGF level significantly and gradually decreased with PIH aggravation (P < 0.05)., Conclusions: The significant decrease of VEGF level after pregnancy was possibly an important factor of PIH pathogenesis.

The clinical performance of packable and conventional hybrid resin composites in Class I restorations for a period of three years was compared using a randomized controlled double-blind clinical trial with self-matching design. A total of 50 pairs of Class I restorations were placed in 32 adult patients by one dentist in a self-matching prospective clinical trial. The paired teeth were divided into the TPH Spectrum/XenoIII (TS) restoration group and the Synergy Compact/One Coat (SC) restoration group according to a random number table. Application of the materials followed the manufacturer's instructions. The restorations were evaluated by two independent evaluators using US Public Health Service (USPHS)-Ryge modified criteria. Statistical analysis was performed using the McNemar's test with Yates' continuity correction. After three years, 40 pairs of restorations were available for evaluation. Four TS and two SC restorations failed due to fracture. Only one TS-restored tooth showed postoperative sensitivity at baseline and the symptom disappeared one week later. Alpha ratings of TS vs SC restorations were as follows: 95% vs 98% for color match, 85% vs 88% for marginal integrity, 88% vs 90% for anatomical form, 85% vs 83% for marginal discoloration, 88% vs 93% for occlusal contact. For both materials, Alpha ratings were 88% for surface texture. The three-year clinical performances of the two restorative materials were satisfactory and not significantly different for each of the parameters evaluated.