三官能团环氧树脂常温固化剂的复配研究及其固化动力学

以间苯二酚二缩水甘油醚(RDGE)和1,1,1-三(对羟基苯基)乙烷为原料,合成了三官能团环氧树脂TEP,并分别与异佛尔酮二胺(IPDA)单一体系和IPDA/2-乙基-4-甲基咪唑(2E4MZ)复合体系进行常温固化。通过DSC、热重分析(TGA)、动态机械热分析仪、耐化学介质以及力学性能测试对比研究了TEP树脂与两种固化体系的固化反应动力学、固化度以及热稳定性。结果表明:复合固化体系较单一固化体系初始表观活化能更低,复合体系固化物的固化程度、玻璃化转变温度、耐腐蚀性均优于单一IPDA固化体系。     

大孔吸附树脂分离纯化淫羊藿EF5黄酮

目的：采用HPLC法和UV法监测AB-8大孔吸附树脂分离纯化以淫羊藿苷、朝藿定A、朝藿定B、朝藿定C和宝藿苷I这五种黄酮为主要成分的淫羊藿EF5黄酮并筛选出最佳分离纯化工艺参数。方法：采用UV法,以淫羊藿总黄酮洗脱率为指标,考察树脂对淫羊藿总黄酮的吸附容量、解吸附率、吸附动力学,以确定树脂分离纯化淫羊藿EF5黄酮的最佳吸附性能;采用HPLC法,以淫羊藿EF5黄酮中五种黄酮单体的洗脱率为指标,考察洗脱液浓度和洗脱液用量等参数,确定淫羊藿EF5黄酮的最佳洗脱参数。结果：AB-8大孔吸附树脂对淫羊藿总黄酮的吸附容量以湿树脂计为（58.37±2.36）mg·g-1,解吸附率为（86.77±2.32）%,最佳吸附时间为180min,最佳洗脱液为60%乙醇,最佳洗脱液用量为5BV,纯化后真空干燥所得棕褐色淫羊藿EF5黄酮粉末中朝藿定A、朝藿定B、朝藿定C、淫羊藿苷和宝藿苷I的含量分别为3.51%、4.87%、1.22%、33.05%、1.36%,淫羊藿EF5黄酮纯度为44%。结论：AB-8大孔吸附树脂分离纯化得到的淫羊藿EF5黄酮的纯度较高,适合工业生产。     

90Y树脂微球治疗患者尿液中90Y放射性活度检测和分析

目的研究患者接受90Y树脂微球选择性内放射治疗(SIRT)后48 h内所排泄尿液中90Y的放射性活度, 为术后患者排泄物的管理提供建议。方法收集3名患者在术后0～24 h和24～48 h两个时间段内排泄的尿液, 并对尿液中的90Y放射性活度进行检测和分析。结果 3名患者术后0～24 h和24～48 h尿液中的90Y放射性活度排泄量分别为(1 266±258)kBq/GBq和(140±106)kBq/GBq, 90Y放射性活度浓度分别为(640±113)kBq/L和(53±12)kBq/L。结论 90Y树脂微球治疗术后肝癌患者0～24 h排泄尿液中的90Y放射性活度比24～48 h高。术后患者可通过增加排泄尿量的方式来加速排出体内游离的90Y;患者住院期间的排泄物应按照HJ 1188-2020《核医学辐射防护与安全要求》的要求处理。     

Novel light-curable materials containing experimental bioactive micro-fillers remineralise mineral-depleted bonded-dentine interfaces

This study aimed at evaluating the therapeutic remineralising effects of innovative light-curable materials (LCMs) containing two experimental calcium silicate-based micro-fillers (TCS) modified with β-TCP only or β-TCP, zinc oxide (ZnO)/polyacrylic acid (PAA) on mineral-depleted bonded-dentine interfaces in simulated body fluids (SBFS). Three experimental LCMs were formulated: (1) resin A, containing a β-TCP-modified TCS (βTCS) micro-filler; (2) resin B, containing a polycarboxylated β-TCP/ZnO-modified TCS (βZn-TCS) micro-filler; and 3) resin C, containing no filler (control). Acid-etched (35% H₃PO₄) dentine specimens were bonded using the three LCMs and submitted to atomic force microscope (AFM)/nano-indentation analysis to evaluate the modulus of elasticity (Ei) and hardness (Hi) across the interface after SBFS storage (24?h/1?m/3?m). The ultramorphology and micropermeability of the resin–dentine interface were evaluated using confocal laser microscopy. Resin–dentine sticks were created and submitted to microtensile bond strength (μTBS) test (SBFS: 24?h/3?m). Scanning electron microscopy (SEM) was performed after de-bonding. The LCMs containing the experimental bioactive micro-fillers reduced the micropermeability and induced a significant increase of the Ei and Hi along the bonding interface. The specimens created using the resin B (βZn-TCS) attained the highest μTBS values both after 24?h and 3?m of SBFS storage. In conclusion, the innovative bioactive light-curable materials tested in this study are able to induce a therapeutic remineralising effect on the nano-mechanical properties and on the sealing ability of mineral-depleted resin–dentine interfaces. The contemporary idea of minimally invasive operative treatment, where therapeutic restorations are performed to combat the carious process and remineralise the dental hard tissues, may be satisfied by using such resin-base systems, containing βTCS or βZn-TCS bioactive micro-fillers.     

阴离子交换树脂除210Bi技术在90Sr分析中的应用

目的 为了克服现有分析标准推荐的硫化铋沉淀法除铋存在的弊端,提升分析结果质量。方法 基于201×7阴离子交换树脂设计了除铋实验流程,并通过加标样品和国际原子能机构（IAEA）国际比对样品分析予以验证。结果 采用阴离子交换树脂进行除铋。在锶、钇、铋去除实验中,锶和钇的化学回收率可分别达到（98.6±0.8）%和（98.5±0.7）%,且未发现有Bi₂S₃沉淀生成;在加标土壤分析中,所得到的分析结果与理论值的相对标准偏差为-2.97%~5.94%,优于标准除铋方法的3.96%~17.80%;采用IAEA国际比对样品进行验证,⁹⁰Sr的报出值与目标值的相对标准偏差介于3.40%~7.09%,结果均可接受。结论 阴离子交换树脂对铋能够实现很好的定量去除,同时不吸附锶和钇。另外,阴离子交换树脂的除铋溶液体系与⁹⁰Sr分析时的解吸体系相同,无需转换体系即可实现快速除铋的目的。与现行标准分析方法相比,基于阴离子交换树脂定量除铋是可行的且更优,能够满足⁹⁰Sr常规分析工作需求。     

Drug-Silica Coassembled Particles Improve Antimicrobial Properties of Endodontic Sealers

IntroductionThe purpose of this study was to assess the antimicrobial activity and flow of root canal sealers after incorporating novel highly loaded antimicrobial drug-silica coassembled particles (DSPs).MethodsDSPs were synthesized through coassembly of silica and octenidine dihydrochloride (OCT) antimicrobial surfactant. DSPs were loaded (1% and 2% wt) into epoxy resin sealer (AH Plus [AH]; Dentsply DeTrey GmbH, Konstanz, Germany) or calcium silicate–based sealer (EndoSequence Bioceramic Sealer (BC); Brasseler, Savannah, GA). OCT release from DSP-modified sealers was determined using liquid chromatography. Antimicrobial activity of sealers against planktonic or biofilm form Enterococcus faecalis was assessed using direct contact and membrane restricted tests. Sealer flow was tested according to ISO6876:2012.ResultsOCT release from BC + 1% or 2% DSPs was above the minimum inhibitory concentration following 2 days throughout the 30-day experiment, whereas OCT release from AH + 1% or 2% DSP was significantly below the minimum inhibitory concentration against E. faecalis (4 μg/mL) over the whole 30-day experimental period. All materials (with or without DSPs) killed planktonic bacteria initially. AH ± 1% or 2% DSPs had no antimicrobial activity after 7 days. BC + 1% or 2% DSPs maintained antibacterial activity over the 30-day period. Both modified and unmodified sealers completely inhibited the growth of E. faecalis biofilms after 24 hours of contact. DSPs decreased the flow of AH and BC sealers; for AH, the reduction was proportional to the amount of DSPs added. All modified and unmodified sealers, except for AH + 2% DSPs, were within the acceptable limits of ISO 6876 flow tests.ConclusionsDSPs enhanced the antimicrobial performance of BC but not AH, whereas the material’s flow remained compliant with ISO 6876 standards. Depending on the sealer, DSPs may enhance antimicrobial efficacy in root canal treatment and potentially improve treatment outcome.     

The effect of new anti-adhesive and antibacterial dental resin filling materials on gingival fibroblasts

ObjectiveAim of this study was to evaluate the biocompatibility of four experimental antiadhesive and antibacterial dental filling composites on human gingival fibroblasts (HGFs).MethodsFor these experimental resin composites a delivery system based on novel polymeric hollow beads, loaded with Tego Protect (Aa1), Dimethicone (Aa2), Irgasan (Ab1) and methacrylated polymerizable Irgasan (Ab2) as active agents was used. The cultured HGFs’ cell integrity, proliferation, viability, collagen synthesis and cytokine release were measured. For this purpose, human gingival fibroblasts were treated with eluates from all four composites and compared with an experimental standard composite (ST). Eluate extraction times 24 h and 168 h were chosen.ResultsStatistical analysis was conducted via a mixed model. Both antibacterial composites reduced proliferation, collagen and cytokine synthesis significantly (p < 0.05), increasing with time of elution. Ab1 did also have a damaging effect on the membrane and on cell viability.SignificanceOverall, it can be concluded that the antiadhesive composites showed clear advantages over the antibacterial composites in terms of biocompatibility. This study also continues to show the potential of the new poly-pore system, as it can be used for a variety of other applications in future composite mixtures.     

用HB-H-6树脂血浆灌流清除细胞因子治疗银屑病的临床研究

目的观察血液灌流治疗严重银屑病患者细胞因子的变化及与临床疗效的关系。方法选择5例银屑病患者,其中男性4例,女性1例,平均年龄32.1岁。均伴有重型肝炎或药物性肝损伤。在常规药物治疗基础上进行血浆灌流治疗,灌流前后分别取患者血浆,测定肿瘤坏死因子α（TNF-α）、白细胞介素1（IL-1）、白细胞介素6（IL-6）和白细胞介素8（IL-8）,检测其他相关生物化学、临床指标并观察记录临床表现情况。结果血液灌流前后比较,TNF-α、IL-1、IL-6和IL-8均显著下降（P〈0.05）,血浆胆红素显著下降（P〈0.05）,其他生物化学及临床指标变化不明显,患者临床治疗效果明显。结论血液灌流能吸附严重银屑病患者血浆中的TNF-α、IL-1、IL-6和IL-8,能明显改善临床症状,可以成为严重银屑病的新的治疗手段。     

新型氟掺杂纳米氧化锆复合树脂填料的制备及其抗菌性能评价

目的 制备一种新型氟掺杂纳米氧化锆复合树脂填料,评价其对口腔变形链球菌的抗菌性能.方法 采用化学沉淀和高温煅烧的方法制备得到含氟量为10 mol％和20 mol％的氟掺杂纳米氧化锆粉体(F-ZrO2),并以不含氟纳米氧化锆粉体作为对照组,通过X射线衍射仪(XRD)和扫描电镜(SEM)对以上3组材料的晶相结构及表面形貌进行表征.通过琼脂扩散实验、最小抑菌/杀菌浓度测试和菌落计数实验对其抗菌性能进行定性定量研究.结果 不同氟掺杂量的纳米氧化锆粉体表面形貌基本不变,均为球状纳米粉体,粒径分布在15 nm～70 nm之间.氟的掺杂使四方相氧化锆峰值被抑制,单斜相氧化锆峰值逐渐变强.在琼脂扩散实验中,10％F-ZrO2和20％F-ZrO2样品片周围均出现明显抑菌环,测量抑菌环平均直径分别为13.46 mm和16.24 mm.菌落计数结果显示:20％F-ZrO2组、10％F-ZrO2组和0％F-ZrO2组的抑菌率依次为96.79％、82.99％和76.91％,各组间差异具有统计学意义(P<0.05).结论 该氟掺杂纳米氧化锆粉体具备优异的抗菌性能,可作为一种新型复合树脂填料以减少继发龋发生的可能性.     

渗透树脂对树脂充填体釉质边缘漂白后微渗漏的影响研究#br#

目的    研究渗透树脂对树脂充填体釉质边缘漂白后微渗漏的影响。方法    选择由郑州大学第一附属医院口腔颌面外科门诊提供的因阻生而拔除的第三磨牙45颗,并在其颊面颈部制备V类洞。将所有离体牙随机分为3组,每组15颗,根据操作方法分别记为树脂充填组、树脂充填+冷光美白组和树脂充填+冷光美白+渗透树脂组。3组离体牙充填后进行500次冷热温度循环,然后在2%的碱性品红溶液中浸泡24 h,把离体牙沿颊舌向纵向剖开,用体式显微镜观察,并用S-EYE软件测量染料渗透深度。结果    3组染料渗透深度总的比较,差异有统计学意义（H = 10.182,P < 0.05）。其中,树脂充填+冷光美白组染料渗透深度大于树脂充填组和树脂充填+冷光美白+渗透树脂组,差异均有统计学意义（P < 0.05）;树脂充填+冷光美白+渗透树脂组染料渗透深度与树脂充填组相比,差异无统计学意义（P > 0.05）。结论    漂白剂加重了树脂充填体边缘的微渗漏,同时渗透树脂的应用能有效减少漂白剂对树脂充填体边缘微渗漏的影响。