Accuracy of computer-aided design/computer-aided manufacturing–generated dental casts based on intraoral scanner data

Background.Little is known about the accuracy of physical dental casts that are based on three-dimensional (3D) data from an intraoral scanner (IOS). Thus, the authors conducted a study to evaluate the accuracy of full-arch stereolithographic (SLA) and milled casts obtained from scans of three IOSs.Methods.The authors digitized a polyurethane model using a laboratory reference scanner and three IOSs. They sent the scans (n = five scans per IOS) to the manufacturers to produce five physical dental casts and scanned the casts with the reference scanner. Using 3D evaluation software, the authors superimposed the data sets and compared them.Results.The mean trueness values of Lava Chairside Oral Scanner C.O.S. (3M ESPE, St. Paul, Minn.), CEREC AC with Bluecam (Sirona, Bensheim, Germany) and iTero (Align Technology, San Jose, Calif.) casts were 67.50 micrometers (95 percent confidence interval [CI], 63.43-71.56), 75.80 μm (95 percent CI, 71.74-79.87) and 98.23 μm (95 percent CI, 94.17-102.30), respectively, with a statistically significant difference among all of the scanners (P < .05). The mean precision values were 13.77 μm (95 percent CI, 2.76-24.79), 21.62 μm (95 percent CI, 10.60-32.63) and 48.83 μm (95 percent CI, 37.82-59.85), respectively, with statistically significant differences between CEREC AC with Bluecam and iTero casts, as well as between Lava Chairside Oral Scanner C.O.S. and iTero casts (P < .05).Conclusion.All of the casts showed an acceptable level of accuracy; however, the SLA-based casts (CEREC AC with Bluecam and Lava Chairside Oral Scanner C.O.S.) seemed to be more accurate than milled casts (iTero).Practical Implications.On the basis of the results of this investigation, the authors suggested that SLA technology was superior for the fabrication of dental casts. Nevertheless, all of the investigated casts showed clinically acceptable accuracy. Clinicians should keep in mind that the highest deviations might occur in the distal areas of the casts.     

Mesenchymal Stem Cell–Derived Extracellular Vesicles Alleviate M1 Microglial Activation in Brain Injury of Mice With Subarachnoid Hemorrhage via microRNA-140-5p Delivery

BackgroundIt is documented that mesenchymal stem cells (MSCs) secrete extracellular vesicles (EVs) to modulate subarachnoid hemorrhage (SAH) development. miR-140-5p expression has been detected in MSC-derived EVs, while the mechanism of MSC-derived EVs containing miR-140-5p in SAH remains unknown. We aim to fill this void by establishing SAH mouse models and extracting MSCs and MSC-EVs.MethodsAfter ALK5 was silenced in SAH mice, neurological function was evaluated, neuron apoptosis was detected by TdT-mediated dUTP-biotin nick end labeling with NeuN staining, and expression of serum inflammatory factors (interleukin-6, interleukin-1β, and tumor necrosis factor-α) was determined by enzyme-linked immunosorbent assay. The effect of ALK5 on NOX2 expression was assessed by western-blot analysis. Targeting the relationship between miR-140-5p and ALK5 was evaluated by dual luciferase assay. Following extraction of MSCs and MSC-EVs, EVs and miR-140-5p were labeled by PKH67 and Cy3, respectively, to identify the transferring of miR-140-5p by MSC-EVs. SAH mice were treated with EVs from miR-140-5p mimic/inhibitor-transfected MSCs to detect effects of MSC-EV-miR-140-5p on brain injury and microglial polarization.ResultsALK5 silencing increased the neurological score and reduced neuron apoptosis and neuroinflammation in SAH mice. ALK5 silencing inhibited M1 microglia activation by inactivating NOX2. ALK5 was a target gene of miR-140-5p. MSC-derived EVs contained miR-140-5p and transferred miR-140-5p into microglia. MSC-EV-delivered miR-140-3p reduced ALK5 expression to contribute to repression of brain injury and M1 microglia activation in SAH mice.ConclusionsMSC-derived EVs transferred miR-140-5p into microglia to downregulate ALK5 and NOX2, thus inhibiting M1 microglia activation in SAH mice.     

体外循环前后血小板功能变化的临床研究

分时段测定20例心脏直视手术患者体外循环(CPB)前后血小板计数、血浆α-颗粒膜蛋白(GMP-140)、血栓烷B2(TXB2)、6-酮-前列腺素F1α(6-K-PGF1α)变化值.结果血小板计数、GMP-140、TXB2测值随着CPB进行均逐渐增加,停机后1h与肝素化10min相比,GMP-140极显著增加(P＜0.01),TXB2显著增加(P＜0.05),血小板计数极明显降低(P＜0.001),而6-K-PGF1α在CPB前后变化不明显.认为体外循环中血小板功能受到明显损害,GMP-140和TXB2是从分子水平反映血小板功能损害的敏感指标.     

miR-140靶向调控SOX2在结肠癌中的作用机制研究

目的 分析miR-140在结肠癌中的作用机制.方法 qRT-PCR检测miR-140在结肠癌细胞和组织中的表达;CCK8法、细胞划痕实验检测miR-140对结肠癌HT29细胞增殖和迁移的影响.TargetScan筛选miR-140的潜在靶基因并通过双荧光素酶报告基因试验进行验证;采用qRT-PCR和Western bl...     

AMPE家兔血浆ET-1、vWF、GPⅡb/Ⅲa及GMP-140水平变化及与心肌受损关系的研究

目的探讨大面积急性肺血栓栓塞（AMPE）家兔心肌受损情况及可能机理。方法模型组10只家兔静注血栓栓子制作AMPE模型;假手术组10只家兔造模过程中只注射生理盐水;对照组10只家兔不做任何处理。于造模成功后2、24 h采集三组静脉血,分别采用微粒子化学发光法、流式细胞仪法、放射免疫法、酶联免疫双抗体夹心法测定血浆心肌肌钙蛋白（CTnI）、血小板膜表面糖蛋白（GPⅡb/Ⅲa）、内皮素-1（ET-1）及血管性假血友病因子（vWF）、α-颗粒蛋白（GMP-140）水平。结果模型组2、24 h血浆CTnI、vWF、GPⅡb/Ⅲa、ET-1、GMP-140水平均明显高于假手术组（P均〈0.05）。结论 AMPE可致心肌受损,机制可能与血浆vWF、GPⅡb/Ⅲa、ET-1、GMP-140水平升高有关。     

miR-140在软骨分化与骨关节炎的研究进展

骨关节炎(OA)是以关节软骨退行性变,关节内滑膜炎症以及周围关节和软骨下骨改变为特征的一种疾病。在OA组织中可观察到软骨细胞凋亡的分子特征,这表明软骨细胞的死亡在OA的发病机制中发挥关键作用。因此,对软骨分化的调控在延缓OA的发展中起到了至关重要的作用。miR-140在关节软骨中特异表达。越来越多的证据表明,miR-140通过抑制转录后水平的基因表达,在软骨细胞分化与OA中发挥重要分子作用。研究miR-140可为发现OA机制及治疗新靶点提供新的借鉴。     

11－去氢－血栓烷B_2测定及其临床应用

为了评估１１－去氢－血栓烷Ｂ２（ＤＨ－ＴＸＢ２）作为体内血小板活化标志物的价值，测定了１００例患者（脑梗塞３２例，脑出血３４例，糖尿病１６例，妊娠高血压综合征１８例）血浆ＤＨ－ＴＸＢ２和血栓烷Ｂ２（ＴＸＢ２）的浓度，并与对照组相比。结果显示患者组ＤＨ－ＴＸＢ２较ＴＸＢ２升高更多；急性期脑血管病患者血浆ＤＨ－ＴＸＢ２均高于对照组最高值，无重叠；而其ＴＸＢ２及α颗粒膜蛋白－１４０（ＧＭＰ－１４０）浓度均与对照组有较多的重叠。结果表明，血浆ＤＨ－ＴＸＢ２浓度测定不受体外血小板活化的影响，是更准确地反映体内血小板活化程度的指标     

类风湿性关节炎患者血浆血小板膜颗粒蛋白(GMP-140)的观察

目的 :探讨类风湿性关节炎 (RA)患者血浆血小板膜颗粒蛋白 (GMP -14 0 )的变化及意义。方法 :用ELISA法检测 42例RA患者和 15例正常人血浆血小板GMP -14 0的含量 ,同时检测血小板计数 (BPC)及血沉 (ESR)。结果 :活动期RA(n=2 4)患者血浆血小板膜GMP -14 0含量 (5 8 32± 8 18μg/L)明显高于缓解期RA患者 (17 18± 2 5 8μg/L ,n=18)和正常对照组 (15 74± 2 33μg/L ,n =15 ) (P均 <0 0 0 1) ,而缓解期RA组与正常对照组之间无统计学差异 (P >0 0 5 )。活动期RA患者中有 15例进行了治疗前后的观察 ,经治疗RA病情得到控制后 ,GMP -14 0明显下降 ,接近正常。活动期RA患者血小板GMP -14 0含量与BPC呈正相关 (r=0 797,P<0 0 1) ;GMP -14 0及BPC与ESR也呈直线正相关 (r =0 45 9及 0 48;P均 <0 0 5 )。结论 :RA患者在病程中不仅有血小板数量的变化 ,同时有血小板的活化 ;其GMP -14 0含量及BPC的变化与疾病活动性有关 ,可能是一种继发性改变。临床上积极治疗原发病是阻止血小板活化 ,防止血栓形成的关键     

急性肺损伤兔血浆颗粒膜蛋白140的改变

目的：观察实验兔急性肺损伤（ＡＬＩ）时血浆颗粒膜蛋白 １４０（ＧＭＰ １４０）的变化并探讨其诊断价值。方法：同种骨髓提取液（ＢＭＥ）经兔颈静脉缓慢恒流注入复制骨髓型ＡＬＩ模型,多时间点检测血中循环内皮细胞（ＣＥＣ）、ＧＭＰ １４０、内皮素 １（ＥＴ １）、血管紧张素转换酶（ＡＣＥ）以及肺组织ＧＭＰ １４０含量。结果：致伤后０．５小时,血中ＣＥＣ、ＧＭＰ １４０、ＥＴ １、ＡＣＥ均显著升高并持续６ 小时,而肺组织ＧＭＰ １４０ 含量降低。血浆ＧＭＰ １４０ 早期升高,幅度较大〔伤后０．５ 小时为（５２．５７±１０．２５）μｇ／Ｌ,较伤前（１６．１８±４．３３）μｇ／Ｌ 高（＞ ３ 倍）,伤后１ 小时达峰值（５６．３２±１２．４３）μｇ／Ｌ〕,与其他指标有较好的相关性。结论：血浆ＧＭＰ １４０可作为临床ＡＬＩ的早期诊断、病情监测和评估的有用指标。