Graphene oxide regulates cox2 in human embryonic kidney 293T cells via epigenetic mechanisms: dynamic chromosomal interactions

To extend the applications of engineered nanomaterials, such as graphene oxide (GO), it is necessary to minimize cytotoxicity. However, the mechanisms underlying this cytotoxicity are unclear. Dynamic chromosomal interactions have been used to illustrate the molecular bases of gene expression, which offers a more sensitive and cutting-edge technology to elucidate complex biological processes associated with epigenetic regulations. In this study, the role of GO-triggered chromatin interactions in the activation of cox2, a hallmark of inflammation, was investigated in normal human cells. Using chromosome conformation capture technology, we showed that GO triggers physical interactions between the downstream enhancer and the cox2 promoter in human embryonic kidney 293T (293T) via p65 and p300 complex-mediated dynamic chromatin looping, which was required for high cox2 expression. Moreover, tumor necrosis factor-α (TNF-α), located upstream of the p65 signaling pathway, contributed to the regulation of cox2 activation through dynamic chromatin architecture. Compared with pristine GO and aminated GO (GO-NH₂), poly (acrylic acid)-functionalized GO (GO-PAA) induced a weaker inflammatory response and a weaker effect on chromatin architecture. Our results mechanistically link GO-mediated chromatin interactions with the regulation of cox2 and suggest that GO derivatives may minimize toxicity in practical applications.     

Assessment of the Remediation Effect of Nano-hydroxyapatite in Exogenous Pb-contaminated Soil Using Toxicity Characteristic Leaching Procedure and Soil Enzyme Activities

This study assessed the level of Pb in soil and five wild plant species (Calotropis procera, Datura alba, Parthenium hysterophorus, Cenchrus ciliaris and Ricinus communis) during all the four seasons. Two busy roads varying in age and traffic volume were selected i.e., Faisalabad–Sargodha road (FSR) and Pindi Bhattian to Lillah (M-2) in the Punjab, Pakistan. Results showed raised levels of Pb in both plants and soil samples along both roads. The range of Pb concentration in plants was 0.08–3.98 and 1.95–4.74 mg kg^??1 for soil. Higher Pb contamination was recorded along FSR road as compared to M-2. Among seasons, the higher Pb concentration was found during summer, probably due to very high temperature. Among all the plants studied, Calotropis procera accumulated the highest level (3.98 mg kg^??1 dry wt.) of Pb; Thus, it can be used as good biomonitor/phytoremediator at Pb contaminated areas.     

五味消毒饮治疗CO_2激光术后复发性尖锐湿疣临床研究

目的:观察五味消毒饮治疗CO_2激光术后复发性尖锐湿疣的临床疗效。方法:将126患者随机分为观察组和对照1组、对照2组,每组各42例。对照1组在CO_2激光术除去尖锐湿疣后仅给予肌肉注射卡介菌多糖核酸注射液,对照2组在CO_2激光术除去尖锐湿疣后待伤口愈合后给予咪喹莫特外用,观察组在上述两组综合治疗的基础上口服中药五味消毒饮。观察三组患者的临床疗效及复发情况。结果:观察组有效率为85.71%,对照1组有效率为64.25%,对照2组有效率为59.52%,观察组与对照1组和对照2组比较,差异具有统计学意义(P0.05),观察组复发率显著低于对照1组、对照2组,差异具有统计学意义(P0.05)。结论:五味消毒饮治疗CO_2激光术后复发性尖锐湿疣疗效显著,复发率低,安全性高。     

CDIC柱状种植体周龈下菌群变化的2年观察

目的：了解种植体周龈下菌群构成变化与种植体周围组织炎的关系，方法：观察64枚CDIC种植体植入术后2年内种植体周龈下细菌构成变化以及相关临床指标。结果：种植体植入术后1月、3月、6月的龈下球菌比值降低。螺旋体，梭形菌比值增高，杆菌，弯曲菌比值差异无显著性意义。术后12月，24月这五类菌的比值接近术前水平，临床菌斑指数，龈沟出血指数高者，种植体周龈下细菌中球菌的比值较低，梭形菌，螺旋体的比值较高。结论：早期进行口腔卫生指导和定期细菌学检测，对提高种植义齿成功很有必要。     

Brnemark种植体支持Nobelpharma杆状覆盖义齿的临床应用

目的 :总结和评价Branemark种植体支持Nobelpharma杆状种植覆盖义齿的应用经验和效果。方法 :将种植体与Nobelpharma杆卡式附着体结合 ,为13例患者制作种植覆盖义齿 ,随访观察1～4年 ,定期拍X线片了解种植体骨结合情况。结果 :种植体稳固 ,X线片未见种植体周有异常骨吸收 ;患者对义齿的固位力十分满意 ,咀嚼效率和舒适性较原有的传统活动义齿有显著的改善 ,提高患者的生活自信心和生命质量。结论 :Branemark种植体支持Nobelphar ma杆状覆盖义齿稳固、美观、易于维护口腔卫生、手术简单和损伤较小 ,对牙槽嵴严重萎缩者尤为适宜 ;采用两个固位卡即可使种植覆盖义齿获得足够的固位力。     

下颌骨应力分布的三维有限元分析

本文用三维有限元方法建立了人类下颌骨的力学模型,采用双侧下颌角加力,模拟了前牙及后牙咬合,对下颌骨的应力分布进行了计算分析。结果表明:应力在下颌骨下缘及牙槽嵴处明显,下颌内侧面应力改变较下颌外侧面明显。     

邻间刷清洁基牙牙面效果研究

目的探讨邻间刷去除基牙牙面软沉积物的效果。方法将备牙后未制作暂时冠的60颗死髓基牙随机分成3组,分别用邻间刷、干棉球、酒精棉球去除基牙牙面附着的软沉积物。结果采用邻间刷法去除牙面软沉积物需要擦拭(4.90±1.25)次,干棉球法需要擦拭(10.80±1.64)次,酒精棉球法需要擦拭(7.60±0.99)次。邻间刷法与干棉球法比较,二者差异有统计学意义(P<0.01);邻间刷法与酒精棉球法比较,二者差异有统计学意义(P<0.01)。结论对于备牙后未制作暂时冠的基牙,在清洁基牙前最好先使用邻间刷去除牙面软沉积物,尤其是牙龈缘处沉积物,再用酒精棉球消毒。     

Surface alteration of human tooth enamel subjected to acidic and neutral 30% hydrogen peroxide

Objectives

To investigate the effects of acidic and neutral 30% hydrogen peroxide (HP) on human tooth enamel in terms of chemical structure, mechanical property, surface morphology and tooth colour.

Methods

Twenty-seven human dental blocks were obtained from premolars and randomly divided into three groups (n = 9): Group acidic HP (30% HP, pH ≈ 3.6), Group neutral HP (30% HP, pH ≈ 7.0) and Group DW (distilled water, pH ≈ 6.8). Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, atomic force microscopy (AFM) investigation, microhardness test and colour measurements were carried out before and after treatments. ATR-FTIR and Raman spectroscopy were analysed and then the carbonate:mineral ratio (C:M), Raman absolute intensity (RAI), Raman relative intensity (RRI), and laser-induced fluorescence intensity (FI) were obtained for evaluation.

Results

The C:M, percentage microhardness and percentage RRI of group acidic HP decreased more significantly than those of group neutral HP (P = 0.02, P = 0.001, P < 0.001, respectively) and group DW (P = 0.01, P = 0.008, P < 0.001, respectively). Whilst group neutral HP and group DW had no statistical difference in above terms (P = 0.818, P = 0.528, P = 0.158, respectively). Significant morphological alterations were observed in group acidic HP. Group acidic HP and neutral HP had no significant difference in percentage FI (P = 0.652) and ΔE (P = 0.906).

Conclusions

This study suggested that neutral 30% HP had the same efficiency in tooth bleaching and it caused less deleterious effects on enamel than acidic 30% HP.