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1.
《Dental materials》2022,38(2):397-408
ObjectivesComposite restorations with calcium fluoride nanoparticles (nCaF2) can remineralize tooth structure through F and Ca ion release. However, the persistence of ion release is limited. The objectives for this study were to achieve long-term remineralization by developing a rechargeable nCaF2 nanocomposite and investigating the F and Ca recharge and re-release capabilities.MethodsThree nCaF2 nanocomposites were formulated: (1) BT-nCaF2:Bisphenol A glycidyl dimethacrylate (BisGMA) and triethylene glycol dimethacrylate (TEGDMA); (2) PE-nCaF2:Pyromellitic glycerol dimethacrylate (PMGDM) and ethoxylated bisphenol A dimethacrylate (EBPADMA); (3) BTM-nCaF2:BisGMA, TEGDMA, and Bis[2-(methacryloyloxy)ethyl] phosphate (Bis-MEP). All formulations contained 15% nCaF2 and 55% glass particles. Initial flexural strength and elastic modulus, F and Ca ion release, recharge and re-release were tested and compared to three commercial fluoride-containing materials.ResultsBT and BTM nCaF2 composites were 3–4 times stronger and had elastic modulus 2 times that of resin-modified glass ionomer controls. PE-nCaF2 had comparable strength to RMGIs. All nCaF2 composites had significant F and Ca ion release and ion rechargeability. In F and Ca recharging cycles, PE-nCaF2 had the highest ion recharging capability among nCaF2 groups, followed by BT-nCaF2 and BTM-nCaF2 (p < 0.05). For all recharge cycles, ion release maintained similar levels, demonstrating long-term ion release was possible. Furthermore, after the final recharge cycle, nCaF2 nanocomposites provided continuous ion release for 42 days without further recharge.SignificanceNovel nCaF2 rechargeable nanocomposites exhibited significant F and Ca ion release over multiple recharge cycles, demonstrating continuous long-term ion release. These nanocomposites are promising restorations with lasting remineralization potential. 相似文献
2.
《Dental materials》2022,38(2):421-430
ObjectivesTo determine the long-term effect on the stability of dentin-resin interfaces after the addition of polylactide (PLA) capsules containing proanthocyanidin (PAC) to adhesive resin.MethodsSub-micron (SM) and micron (M) size capsules containing PACs were produced using a combination of emulsification and solvent evaporation techniques and characterized. Human dentin surfaces (n = 8) were etched (35% glycolic acid) and primed (15% enriched Vitis vinifera extract solution - VVe), followed by the application of an experimental adhesive containing 0 (control), 1.5 wt% of SM or M PAC-filled PLA capsules light cured for 40 s. A crown was built using commercial composite. After 24 h-immersion (37 °C) in simulated body fluid, specimens were serially sectioned into resin-dentin beams. Microtensile bond strength (TBS), micro-permeability and fracture pattern were assessed immediately and after 1 and 2 years. Data were statistically analyzed using two-way ANOVA and post-hoc test (α = 0.05).ResultsPolydisperse capsules were manufactured with average diameter of 0.36 µm and 1.08 µm for SM and M, respectively. The addition of capsules did not affect TBS (p = 0.889). After 2 years, TBS significantly decreased in SM (p = 0.006), whereas M showed similar initial values (p = 0.291). Overall, less micro-permeability was found in M than the control and SM group (p < 0.001). After 2 years, fractured surfaces from capsule-containing groups failed within the adhesive layer while control fractured at the bottom of the hybrid layer.SignificanceThe addition of PAC-filled PLA microcapsules in a dental adhesive did not affect the bond strength while increased and sustained the protection against micro-permeability in the interface, likely due to release of PACs. 相似文献
3.
目的:探讨微创Chevron合并外侧软组织松解治疗轻中度拇外翻畸形的短期疗效。方法:自2019年1月至2021年12月,采用微创Chevron截骨加外侧软组织松解术式治疗67例(80足)轻中度拇外翻患者,男5例(6足),女62例(74足);年龄20~60(47.2±9.7)岁;轻度(拇外翻角 ≤ 20°)54例(64足),中度(20°<拇外翻角 ≤ 40°)13例(16足)。比较术前与末次随访时拇外翻角(hallux valugs angle,HVA),Ⅰ-Ⅱ跖骨间角(Ⅰ-Ⅱ intermetatarsal anlge,Ⅰ-Ⅱ IMA),远端跖骨关节角(distal metatarsal articular angle,DMAA),籽骨Hardy评分变化,并采用北美足踝外科协会拇趾-跖趾关节(American Orthopaedic Foot and Ankle Society''s Hallux Metatarsophalanged-Interphalangeal,AOFAS Hallux MTP-IP)评分进行疗效评价。结果:67例患者获得随访,时间6~23(13.7±6.5)个月。术前HVA、Ⅰ-Ⅱ IMA、DMAA、籽骨Hardy评分、AOFAS Hallux MTP-IP评分分别为(27.5±7.0)°,(17.4±4.1)°,(11.4±3.8)°,(4.9±2.6)分,(58.2±9.1)分;末次随访时时分别为(8.3±4.8)°,(6.9±3.0)°,(3.9±2.4)°,(2.7±1.1)分,(91.3±2.2)分;术前与末次随访比较差异有统计学意义(P<0.05)。轻度患足(64足)和中度患足(16足)术前各项影像学指标和AOFAS Hallux MTP-IP评分比较差异有统计学意义(P<0.05);末次随访时,上述指标比较差异无统计学意义(P>0.05);从各指标改善程度来看,中度拇外翻患足HVA、Ⅰ-ⅡIMA、籽骨Hardy评分、AOFAS Hallux MTP-IP评分优于轻度拇外翻患足(P<0.05)。术后4例出现截骨部位切口周围红肿,经局部换药及口服抗生素均治愈。结论:微创Chevron截骨联合外侧软组织松解术对于轻中度拇外翻有良好的矫形效果及功能改善。 相似文献
4.
《Journal of microbiology, immunology, and infection》2021,54(4):680-686
BackgroundVitamin D is essential in the host defense against tuberculosis (TB). Suboptimal vitamin D status is common in the hemodialysis population. Hemodialysis patients have an increased risk compared to the general population latent tuberculosis infection (LTBI). However, the association between vitamin D deficiency and LTBI in this population remains unclear.Materials and methodsWe conducted a cross-sectional study between March and May 2017. Interferon-gamma release assay (IGRA) through QuantiFERON-TB Gold In-Tube was used to assess LTBI. Plasma 25-hydroxycholecalciferol (25-OHD) levels were measured by Elecsys Vitamin D Total assay. Suboptimal vitamin D levels included vitamin D insufficiency 20–29 ng/mg and vitamin D deficiency <20 ng/mL. Predictors for LTBI were analyzed.ResultsA total of 287 participants were enrolled. The suboptimal vitamin D level was 31.4% (90/287), which including the vitamin D deficiency was 13.9% (40/287). A total of 49.1% (141/287) people received nutritional vitamin D supplementation. The prevalence of IGRA positivity in this study was 25.1% (72/287). There was no significant difference in vitamin D concentrations or the proportion of vitamin D supplementation among the IGRA-positive and IGRA-negative groups (p = 0.789 and 0.496, respectively). In multivariate analysis, age >65 years old (odds ratio (OR), 1.89; 95% CI, 1.08–3.31; p = 0.026) and TB history (OR, 3.51; 95% CI, 1.38–8.91; p = 0.008) were independent predictors of IGRA positivity.ConclusionThis is the first study to report that vitamin D deficiency was not associated with IGRA positivity in a hemodialysis population. Aging and TB history were both independent predictors for LTBI. 相似文献
5.
6.
目的:探析慢性肾脏病患者采取非洛地平缓释片联合百令胶囊治疗对改善肾功能指标的效果。方法:选取2016年11月至2020年7月芜湖市第一人民医院收治的慢性肾脏病患者60例作为研究对象,按照随机数字表法随机分为对照组和观察组,每组30例。对照组采用非洛地平缓释片治疗,观察组采用非洛地平缓释片联合百令胶囊治疗,比较2组患者尿素氨(BUN)水平、血肌酐(SCr)、24 h尿蛋白定量、胱抑素C(Cys-C)、血清降钙素原(PCT)、超敏C反应蛋白(hs-CRP)以及治疗有效率等指标。结果:观察组患者的BUN、SCr、24 h尿蛋白定量、Cys-C等肾功能水平降低幅度明显大于对照组,差异有统计学意义(P<0.05);观察组患者PCT、hs-CRP等炎症介质水平降低幅度明显大于对照组,差异有统计学意义(P<0.05);观察组、对照组治疗有效率分别为96.67%、76.67%,观察组治疗有效率明显高于对照组,差异有统计学意义(P<0.05)。结论:慢性肾脏病患者采取百令胶囊联合非洛地平缓释片进行治疗在改善肾功能、炎症介质方面有着非常明显的优势,还可提升治疗有效率,对改善患者治疗预后有着明显的优势,应推广应用。 相似文献
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8.
目的 成功制备雷公藤甲素(3-丙羧基)三苯基溴化膦(TPP)-聚乙二醇-b-聚己内脂(PEG-PCL)脂质体(Tr@TPP/Lip),评价其靶向性及促肝肿瘤细胞凋亡效果。方法 采用正交试验优选Tr@TPP/Lip的制备工艺,再研究该载药系统的粒径、Zeta电位、载药量、包封率和多分散系数及透射电镜微观形态,评价Tr@TPP/Lip的稳定性、溶血性、释放情况;采用荧光试验,研究脂质体与肝肿瘤细胞的融合情况、线粒体靶向性和肝脏靶向性;在等剂量给药条件下,评价Tr@TPP/Lip促肝癌细胞凋亡效果。结果 正交试验优选的Tr@TPP/Lip粒径为(113.5±17.6)nm,Zeta电位(12.6±0.7)mV,包封率为(71.3±3.2)%,载药量为(3.9±1.1)%,多分散系数为0.12±0.04;透射电子显微镜图片显示Tr@TPP/Lip呈规则圆球形,该脂质体稳定性良好,具有较小的溶血率和良好的缓释药物性能;荧光试验结果显示,TPP阳离子能促进脂质体与肿瘤细胞的融合,并靶向线粒体,还能提高药物在肝肿瘤部位的靶向和滞留效果;细胞药效结果显示,Tr@TPP/Lip具有良好的促肝肿瘤细胞凋亡效果,能明显降低线粒体膜Zeta电位、增加细胞内活性氧水平和Caspase-3的释放,显著增加促凋亡蛋白Bcl-2、减少抗凋亡Bax蛋白的表达,这些细胞凋亡试验结果均明显优于雷公藤甲素普通脂质体和雷公藤甲素。结论 Tr@TPP/Lip具有较好的线粒体靶向功能,能增强药物促肝肿瘤细胞凋亡效果。 相似文献
9.
=O4 探讨结核感染T细胞斑点试验(T-cell spot of Tuberculosis,T-SPOT.TB)在手、腕部腱鞘结核诊断中的临床应用价值。方法通过对2012年1月至2018年1月我院收集 64例怀疑手、腕部腱鞘结核临床资料进行回顾性分析,根据病理诊断及临床表现判断有无结核分枝杆菌感染;全部病例均经过T-SPOT.TB和胶体金标法分别进行体外γ-干扰素释放试验和血清结核抗体检测,采用Kappa、χ2检验进行统计学分析。-结果- 共收集分析相关病例64例,其中诊断为手、腕部腱鞘结核(结核病例)21例,非手、腕部腱鞘结核(非结核病例)43例。经T-SPOT.TB检测,结核病例阳性者20例,非结核病例阴性者40例,灵敏度为95.2%,特异度为93.0%,阳性预测值为87.6%,阴性预测值为97.6%。经胶体金标法检测血清结核抗体,结核病例阳性者5例,非结核病例阴性者37例,灵敏度为23.8%,特异度为86.0%,阳性预测值为45.4%,阴性预测值为69.8%。与临床诊断比较,T-SPOT.TB和胶体金标法的Kappa值分别为0.862和0.112,T-SPOT.TB比胶体金标法具有更好的一致性,且灵敏度、阳性预测值和阴性预测值均明显更高,差异有统计学意义(P<0.05)。-结论- T-SPOT.TB在手、腕部腱鞘结核诊断中具有良好的辅助诊断价值。 相似文献
10.
嵌合抗原受体T细胞(CAR-T)治疗进展迅速,其安全性问题一直受到广泛关注。第62届美国血液学会年会上针对其主要不良反应的发生机制、预测指标及治疗策略进行了一系列报道,对全面提高CAR-T治疗的安全性具有一定的指导意义。 相似文献