Comparative Study of 6 Rotary Nickel-Titanium Systems and Hand Instrumentation for Root Canal Preparation in Severely Curved Root Canals of Extracted Teeth

IntroductionSome improvements have been developed with new generations of nickel-titanium (NiTi) rotary instruments that led to their successful and extensive application in clinical practice. The purpose of this in vitro study was to compare the root canal preparations performed by using GT Series X and Twisted File systems produced by innovative manufacturing process with Revo-S, RaCe, Mtwo, and ProTaper Universal systems manufactured directly from conventional nitinol and with stainless steel K-Flexofile instruments.MethodsThe mesiobuccal root canals of 140 maxillary first permanent molars that had between 30°–40° curvature angle and 4- to 9-mm curvature radius of the root canal were used. After root canal preparations made by using GT Series X, Twisted File, Revo-S, RaCe, Mtwo, and ProTaper Universal NiTi rotary systems and stainless steel K-Flexofile instruments, transportation occurred in the root canal, and alteration of working length (WL) was assessed by using a modified double-digital radiographic technique. The data were compared by the post hoc Tukey honestly significant difference test.ResultsNiTi rotary systems caused less canal transportation and alteration of WL than K-Flexofile instruments (P < .05). There was no significant difference between NiTi rotary system groups at any levels (P > .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P < .05).ConclusionsGT Series X and Twisted File rotary systems produced with innovative process were concluded to shape the curved canals to result in minimal canal transportation, similar to Revo-S, RaCe, Mtwo, and ProTaper Universal rotary systems manufactured by traditional methods.     

In Vitro Fracture Resistance of Endodontically Treated Roots Filled with a Bonded Filling Material or Different Types of Posts

AimThis study aimed to compare the fracture resistance of roots filled with a bonded material, fiber posts, or titanium post systems.MethodsCanals in the first group were filled with AH Plus and gutta-percha cones, and roots in the second group were filled with Epiphany sealer and Resilon cones. The root fillings (60 roots) were removed up to 4 mm from the canal apex to obtain 10-mm-deep post spaces, and posts were cemented. The groups were as follows: AH Plus control group, Epiphany control group, AH Plus fiber post group, AH Plus titanium post group, Epiphany fiber post group, and Epiphany titanium post group. Fracture tests were performed by using an Instron testing machine. The force was applied at a 45° axial angle with a constant speed of 1 mm/min. For each sample, the force at which fracture occurred was recorded in units of newtons. Statistical analysis was carried out by using analysis of variance test.ResultsThere was no statistically significant difference between all groups (P > .05).ConclusionsTitanium posts, fiber posts, and Epiphany root canal filling systems were found to have no reinforcing effect on endodontically treated roots.     

Visual rehabilitation by using corneal wavefront-guided transepithelial photorefractive keratectomy for corneal opacities after epidemic keratoconjunctivitis

International Ophthalmology - To evaluate long-term visual and refractive outcomes of corneal wavefront-guided transepithelial photorefractive keratectomy (t-PRK) with mitomycin C for the treatment...     

Gossypol stimulates opening of a Ca2+‐ and Na+‐permeable but Ni2+‐ and Co2+‐impermeable pore in bEND.3 endothelial cells

Gossypol, a polyphenolic dialdehyde toxin isolated from cotton seed, has anti‐cancer properties and has recently shown some success in the treatment of glioma. Its effects on brain neurons and blood vessels are poorly understood. In this work we examined the effects of gossypol on cytosolic Ca²⁺ concentration ([Ca²⁺]_i) of mouse brain bEND.3 endothelial cells. Cell viability tests revealed that after 3 hour and 18 hour exposures, 10 µmol/L gossypol caused 23% and 65% cell death, respectively; 3 µmol/L gossypol caused no and 21% cell death, respectively. [Ca²⁺]_i was raised concentration‐dependently by 1‐10 µmol/L gossypol. We then explored the Ca²⁺ signalling triggered by 3 µmol/L gossypol, which inflicted minimal toxicity: the Ca²⁺ signal was composed largely of Ca²⁺ influx and to a small extent, intracellular Ca²⁺ release. Such Ca²⁺ influx was much larger than store‐operated Ca²⁺ influx triggered by maximal Ca²⁺ pool depletion. The Ca²⁺ influx triggered by 3 and 10 µmol/L gossypol caused NO release and cell death, respectively. Gossypol also triggered influx of Mn²⁺ and Na⁺, but not Ni²⁺ and Co²⁺. Gossypol‐triggered Ca²⁺ signal was inhibited only by 14% and 37% by 100 µmol/L La³⁺ and 10 µmol/L nimodipine, respectively; and not suppressed at all by 5 mmol/L Ni²⁺. Gossypol‐triggered Ca²⁺ signal was suppressed by 78% by 30 µmol/L ruthenium red, suggesting gossypol may act on TRPV channels. Our results suggest gossypol triggered opening of a non‐selective cation pore, possibly a member of the TRPV family.     

Salbutamol‐induced Decrease in Augmentation Index is Related to the Parallel Increase in Heart Rate

The change in augmentation index following salbutamol inhalation has been applied to evaluate endothelial function. We examined the contribution of salbutamol‐induced increase in heart rate to the observed decrease in augmentation index. Haemodynamics were recorded using whole‐body impedance cardiography and continuous pulse wave analysis from tonometric radial blood pressure. All subjects (n = 335, mean age 46, body mass index 26, 48% men) were without medications with cardiovascular influences. The effects of salbutamol inhalation (0.4 mg) versus the endothelium‐independent agent nitroglycerin resoriblet (0.25 mg) were examined during passive head‐up tilt, as the haemodynamic influences of these compounds depend on body position. Salbutamol decreased augmentation index by ~3‐4% units in supine and upright positions. Although salbutamol moderately increased cardiac index (+4.5%) and decreased systemic vascular resistance (?8.5%), the significant haemodynamic explanatory factors for decreased augmentation index in multivariate analysis were increased supine heart rate, and increased upright heart rate and decreased ejection duration (p < 0.001 for all, r² = 0.36–0.37). Sublingual nitroglycerin decreased supine and upright augmentation index by ~15% units and ~23% units, respectively. The haemodynamic explanatory factors for these changes in multivariate analysis were increased heart rate, reduced ejection duration and reduced systemic vascular resistance (p ≤ 0.021 for all, r² = 0.22–0.34). In conclusion, the lowering influence of salbutamol on augmentation index may be largely explained by increased heart rate, suggesting that this effect may not predominantly reflect endothelial function.     

止咳平喘十二味合剂治疗痰热郁肺型咳嗽变异型哮喘临床研究

目的：观察止咳平喘十二味合剂治疗痰热郁肺型咳嗽变异型哮喘的临床疗效及其对肺功能和外周血免疫球蛋白E（IgE）、肿瘤坏死因子-α（TNF-α）、白细胞介素-8（IL-8） 的影响。方法：将2018 年9 月—2020 年8 月间由呼吸科收治且符合研究条件的咳嗽变异型哮喘患者92 例,按随机化原则分为2 组各46 例。对照组采用孟鲁司特钠联合多索茶碱治疗,观察组在对照组治疗方案的基础上联合止咳平喘十二味合剂治疗,2 组均治疗2 周,比较2 组治疗前后咳嗽症状积分、咳嗽相关生活质量评分、肺功能指标及外周血IgE、TNF-α、IL-8。结果：治疗2 周后,观察组咳嗽症状积分低于对照组（P＜0.05）;咳嗽相关生活质量评分高于对照组（P＜0.05）,观察组肺功能指标第1 秒用力呼气容积（FEV1）、呼气峰值流速（PEF） 及用力呼气中期流速（MMEF75/25） 值均高于对照组（P＜0.05）,观察组外周血IgE、TNF-α、IL-8 均低于对照组（P＜0.05）。结论：止咳平喘十二味合剂可显著降低痰热郁肺型咳嗽变异型哮喘患者外周血IgE、TNF-α 和IL-8 等炎症因子水平,改善肺功能,减轻咳嗽症状,提高咳嗽相关生活质量。