Caffeic Acid–coated Nanolayer on Mineral Trioxide Aggregate Potentiates the Host Immune Responses,Angiogenesis, and Odontogenesis

IntroductionThe aim of this study was to investigate whether mineral trioxide aggregate (MTA) can be modified with caffeic acid (CA) to form caffeic acid/mineral trioxide aggregate (CAMTA) cement and to evaluate its physicochemical and biological properties as well as its capability in immune suppression and angiogenesis.MethodsMTA was immersed in trishydroxymethyl aminomethane buffer with CA to allow coating onto MTA powders. X-ray diffractometry and tensile stress-strain tests were conducted to assess for physical characteristics of CAMTA and to evaluate for successful modification of MTA. Then, the CAMTA cement was immersed in simulated body fluid to evaluate its hydroxyapatite formation capabilities and Si release profiles. In addition, RAW 264.7 cells and human dental pulp stem cells were used to evaluate CAMTA’s immunosuppressive capabilities and cell responses, respectively. hDPSCs were also used to assess CAMTA’s angiogenic capabilities.ResultsThe X-ray diffractometry results showed that CA can be successfully coated onto MTA without disrupting or losing MTA’s original structural properties, thus allowing us to retain the initial advantages of MTA. CAMTA was shown to have higher mechanical properties compared with MTA and had rougher pitted surfaces, which were hypothesized to lead to enhanced adhesion, proliferation, and secretion of angiogenic- and odontogenic-related proteins. In addition, it was found that CAMTA was able to enhance hydroxyapatite formation and immunosuppressive capabilities compared with MTA.ConclusionsCAMTA cements were found to have improved physicochemical and biological characteristics compared with their counterpart. In addition, CAMTA cements had enhanced odontogenic, angiogenic, and immunosuppressive properties compared with MTA. All of the results of this study proved that CAMTA cements could be a biomaterial for future clinical applications and tissue engineering use.     

Flavonoids and stilbenoids as a promising arsenal for the management of chronic arsenic toxicity

Rapid industrial and technological development has impacted ecosystem homeostasis strongly. Arsenic is one of the most detrimental environmental toxins and its management with chelating agents remains a matter of concern due to associated adverse effects. Thus, safer and more effective alternative therapy is required to manage arsenic toxicity. Based on existing evidence, native and indigenous plant-based active biomolecules appear as a promising strategy to mitigate arsenic-induced toxicity with an acceptable safety profile. In this regard, various phytochemicals (flavonoids and stilbenoids) are considered important classes of polyphenolic compounds with antioxidant and chelation effects, which may facilitate the removal of arsenic from the body more effectively and safely with regard to conventional approaches. This review presents an overview of conventional chelating agents and the potential role of flavonoids and stilbenoids in ameliorating arsenic toxicity. This report may provide a roadmap for identifying novel prophylactic/therapeutic strategies for managing arsenic toxicity.     

Assessment of heavy metals by ICP-OES and their impact on insulin stimulating hormone and carbohydrate metabolizing enzymes

Arsenic (As) and cadmium (Cd) have recently emerged as major health concerns owing to their strong association with diabetes mellitus (DM). We aimed to investigate the heavy metals exposure towards incidence of DM at various enzymatic and hormonal levels. Additionally, association of As and Cd with Zinc (Zn, essential metal) was also evaluated. Spot urine samples were collected to assess As, Cd and Zn through ICP-OES. Serum was analyzed by assay method for fasting blood glucose, liver and renal function biomarkers. ELISA was performed to investigate the impact of heavy metals on HbA1c, α-amylase, DPP-IV, IGF-1, leptin, GSH, MDA, SOD, HDL, FFA, TG and interleukin (IL)-6. Association of heavy metals with DM was measured by odds ratio (OR) and level of significance was assessed by Chi-squared test. Unpaired student's t-test was used to compare DM-associated risk factors in heavy metals-exposed and unexposed participants. As and Cd were detectable in 75.4% and 83% participants with mean concentration of 75.5 ppb and 54.5 ppb, respectively. For As exposure, OR in the third quartile was maximum ie 1.34 (95% CI, 0.80 to 2.23), however the result was not statistically significant (P > .05). For Cd exposure, OR in the fourth quartile was considerably high, 1.62 (95% CI, 1.00 to 2.61), with a significant probability value (P < .05). Urinary Cd was negatively associated with Zn. As and Cd exposure increases the incidence of DM in the general population. Impaired hormonal and enzymatic levels in diabetic and non-diabetic exposed participants reflect the multiple organ damage by heavy metal exposure.     

氧化砷对小鼠腹水型肝癌细胞的作用

目的 :研究氧化砷对移植性腹水型肝癌细胞的抗癌作用。方法 :肝癌细胞 (1 8× 10 7)接种入小鼠腹腔。对照组注射NS(0 8mL) ,余组用氧化砷 (1,2 ,3μmol/L)腹腔注射 ,每日 1次 ,共 10日。结果 :第 10天腹水细胞计数 ,1,2和 3μmol/L组瘤细胞锐减 (P <0 0 5 ) ,但第 16天腹水肿瘤细胞急骤增加。结论 :氧化砷对腹水肿瘤细胞有暂时抑制作用。     

As2O3处理前后K562细胞基因表达变化的基因芯片检测

目的应用基因芯片研究三氧化二砷(As2O3)处理前后K562细胞基因表达的变化.方法提取As2O3处理前后K562细胞的总RNA,纯化为mRNA后再反转录为cDNA.cDNA经限制性内切酶Sau3AI切割后,cDNA片段分别用Cy3和Cy5标记,与自制的包含348个基因片段的胎盘库芯片杂交.结果杂交结果经扫描和软件分析,发现了11个差异表达的基因片段,其中有3个基因片段与细胞凋亡密切相关.结论我们构建的胎盘库基因芯片可以成功地用于研究药物作用前后基因表达的变化.     

三氧化二砷纳米微粒对抑制兔血管平滑肌细胞增殖作用的实验研究

目的 了解纳米微粒与普通剂型的三氧化二砷（As2O3）对抑制体外培养的兔血管平滑肌细胞（VSMC）增殖作用的差别。方法 对照组为不加药物的细胞，实验组为3μmol／L纳米微粒和普通剂型的As2O3，干预体外培养的兔VSMC细胞72h，进行四唑氮盐（MTT）染色测定细胞吸光度（A）值。用流式细胞仪检测细胞凋亡情况，提取细胞DNA，进行凝胶电泳分析，将3组的结果进行比较。结果 3μmol／L纳米剂型的As2O3，干预细胞，细胞数量随作用时间的延长逐渐减少，细胞生长明显受抑制，而普通剂型干预细胞，生长受抑制程度较纳米剂型弱。24h时，对照组、3μmol／L普通剂型组与纳米组，A值分别为0．68±0．10、0．58±0．12、0．33±0．12，48h时分别为0．79±0．11、0．48±0．14、0．28±0．11，72h时分别为0．96±0．13、0．34±0．15、0．20士0．06，差异均有统计学意义（Ⅳ值分别为10．934、15．039、15．539，P值均〈0．01）。流式细胞仪检测，纳米剂型As2O3、普通剂型As2O3干预及对照组的细胞干预48h，细胞增殖率分别为44．97％、58．54％、74．02％，早期凋亡率分别为16．89％、11．27％、11．20％，晚期凋亡率分别为26．56％、23．60％、12．46％，坏死细胞分别为11．58％、6．59％、2．32％。DNA电泳，As2O3干预细胞，可见凋亡梯形条带，部分细胞坏死，呈模糊的无间隔片状条带。纳米剂型药物作用的细胞DNA条带，梯形条带更多、更模糊。结论 As2O3，可以抑制体外培养的VSMC增殖，且纳米剂型As2O3较普通剂型的As2O3，对细胞抑制作用更强。     

谷胱甘肽、自由基在砷剂诱导卵巢癌细胞凋亡中的作用

目的　观察谷胱甘肽、自由基在砷剂诱导卵巢癌细胞凋亡中的作用。方法　砷剂孵育卵巢癌细胞 4 8h后 ,琼脂糖凝胶电泳及流式细胞仪检测细胞凋亡 ,分光光度法检测细胞内谷胱甘肽、活性氧及丙二醛含量。结果　砷剂具有诱导卵巢癌细胞凋亡作用 ,砷剂诱导后细胞内谷胱甘肽含量减少 (P <0 .0 1)、活性氧及丙二醛含量增加(P <0 .0 5 )。结论　氧化还原系统的改变是砷剂诱导卵巢癌细胞凋亡的重要途径之一。     

三氧化二砷对CO2气腹下小鼠肿瘤腹壁戳口种植影响的实验研究

目的 研究腹腔内注射三氧化二砷(arsenic trioxide,As2O3)对小鼠CO2气腹下肝癌H22转移的影响. 方法 昆明鼠40只(清洁级),中腹部穿刺置入1 mm套管针,自套管针注入1×106肿瘤细胞后,建立CO2气腹,压力8 mm Hg,时间30 min.术后随机分4组,每组10只,分别腹腔内注入生理盐水,1 ml;As2O3(2 mg/kg),1 ml;As2O3(4 mg/kg),1 ml;As2O3(4mg/kg)+肝素(10 U/ml),共1 ml.气腹后第3、7天测量肿瘤黏附因子(CD44)、血管内皮生长因子(vascular endothelial growth factor,VEGF)的变化;比较各组生存状态、腹围、体重变化及转移瘤直径.结果 气腹后第3、7天,与对照组相比,各As2O3组CD44、VEGF表达均明显降低(P＜0.05).2个高剂量组的气腹后第3天VEGF、第7天CD44比低剂量组降低明显(P＜0.05).4组戳口种植率分别为9/10、8/10、7/10、6/10,差异无显著性(x2=2.667,P=0.446). 结论 As2O3对CO2气腹腹腔镜肿瘤生长转移有抑制作用.     

不同浓度三氧化二砷对哮喘小鼠气道树突状细胞的作用

目的 :研究 3种不同浓度三氧化二砷 (arsenictrioxide,As2 O3)对哮喘小鼠气道树突状细胞 (dendriticcells ,DCs)分布和募集的作用。方法 :BALB c小鼠 5 0只随机分为5组 ,即对照组、哮喘组、低剂量 (1mg kg)As2 O3组、中剂量 (5mg kg)As2 O3组和高剂量 (10mg kg)As2 O3组。采用免疫组织化学染色、计算机图像分析和扫描电镜技术分别检测气道DCs。结果 :对照组小鼠整个肺组织构成了一个NLDC 14 5 +DCs网络 ,NLDC 14 5 + DCs密度从大气道到小气道分别为(5 0 0± 5 0 )个 mm2 到 (6 0± 10 )个 mm2 上皮面积 (P <0 0 5 ) ;哮喘组小鼠肺内NLDC 14 5 + DCs密度较对照组显著增加 (P <0 .0 1) ,但不影响其肺内分布 ;哮喘小鼠经As2 O3处理后 ,肺内NLDC 14 5 + DCs密度显著下降 (P <0 0 1) ,但不影响其肺内分布 ,且三种不同浓度砷剂处理组间无显著性差异 (P >0 0 5 )。结论 :下调肺内DCs密度而不影响其肺内分布 ,可能是As2 O3治疗哮喘的一个重要机制 ;低剂量As2 O3治疗哮喘具有潜在的应用前景。