浓硫酸酸蚀聚醚酮酮的时间对其与牙本质剪切粘接强度的影响

目的研究浓硫酸酸蚀聚醚酮酮(polyether?ketone?ketone,PEKK)不同时间对其与牙本质剪切粘接强度的影响,为临床使用PEKK修复体的粘接操作提供科学依据。方法制备PEKK试件44个,随机平均分为A、B、C、D 4组:A组为对照组,仅用水磨砂纸打磨;B组、C组、D组为实验组,分别用98%浓硫酸酸蚀经打磨试件表面5 s、30 s、60 s。另外,每组随机抽取1个试件用慢速切割机制备出剖面,在扫描电镜下观察其剖面的表面形貌。4组试件与牙本质通过树脂粘接后在37℃蒸馏水浸泡24 h,测量剪切粘接强度后统计分析,通过扫描电子显微镜与体视显微镜检查试件断裂界面,统计粘接失败类型。结果B组PEKK试件酸蚀处理后剖面呈海绵状且孔隙大小均匀,C组、D组可见试件剖面有破坏状孔蚀样结构;剪切粘接强度B组(16.84±1.84)MPa、C组(12.33±1.22)MPa和D组(6.44±1.18)MPa均大于A组(3.99±1.06)MPa(P<0.05),其中B组与牙本质的剪切粘接强度最高(16.84±1.84)MPa。结论采用98%浓硫酸酸蚀PEKK表面5 s处理方法可以使PEKK与牙本质获得较好的剪切粘接强度。     

A novel π-conjugated poly(biphenyl diimide) with full utilization of carbonyls as a highly stable organic electrode for Li-ion batteries

Organic carbonyl redox polymers, especially conjugated polyimides with multiple reversible redox centers have attracted considerable attention as electrode materials for organic Li-ion batteries. However, the low utilization of carbonyls hindered their potential applications in energy storage. Herein, a novel π-conjugated polyimide (PBPI) based on biphenyl diimide (BPI) containing two seven-membered imide rings is developed. PBPI is used as an anode material for organic Li-ion batteries, which show high conductivity and insolubility in the electrolyte and enable intercalation of four Li-ions per BPI unit, thus contributing to a reversible capacity of 136 mA h g⁻¹ at 100 mA g⁻¹ with coulombic efficiency close to 100%. Moreover, the battery based on PBPI manifested superior high-rate performance (65 mA h g⁻¹ at 2000 mA g⁻¹) as well as significant cycling stability (over 1600 cycles at 100 mA g⁻¹). Remarkably, the full redox-active site (C O) utilization of an aromatic diimide core to achieve its full potential applications is reported for the first time. This work provides a new strategy for developing redox π-conjugated polyimides and accommodation of more alkaline ions for high performance battery systems.

A novel π-conjugated polyimide based on the two seven-membered imide rings-containing BPI was reported, which be used as a highly stable anode electrode material with full utilization of carbonyls for the application organic Li-ion batteries.     

慢性肾病患者血清Klotho，HE4，UMOD表达水平与疾病预后的相关性研究

目的　研究慢性肾病(chronic kidney disease, CKD)患者血清Klotho,人附睾蛋白4(HE4)和尿调节素 (UMOD)表达水平在评估疾病预后中的参考价值。方法　对120例CKD患者及100例健康体检对照者血清同时应用ELISA检测Klotho和HE4,电化学发光法检测UMOD表达水平,分析各因子与肾小球滤过率(GFR)之间的关系。患者随访12个月后,根据GFR下降幅度分为恶化组和稳定组,比较两组之间血清因子变化差异,采用Kaplan-Meier生存曲线分析血清因子与预后的关系。结果　CKD患者血清Klotho,UMOD,GFR和HE4表达水平与健康对照组相比,差异均有统计学意义（t=22.492,58.235,23.668和33.341,均P<0.05）。Klotho,UMOD与GFR呈现正相关性（r=0.682,0.582,P<0.001）,HE4与GFR呈负相关性（r=-0.627,P<0.001）。随访结束时血清Klotho,UMOD水平明显低于随访前,HE4水平明显高于随访前,恶性组患者的变化幅度与稳定组相比差异有统计学意义（t=13.263,18.600和16.645,均P<0.001 5）。随访12个月后患者死亡45例（37.50%）,高Klotho,UMOD水平组不良预后风险低于低Klotho,UMOD水平组,高HE4水平组不良预后风险高于低HE4水平组,差异均有统计学意义（χ2=4.511,3.960,7.484;P=0.034,0.047,0.006）。结论　慢性肾病患者血清中Klotho,HE4,UMOD均存在异常表达,其中血清Klotho,UMOD水平降低以及HE4水平升高可增加肾功能恶化风险,三种血清因子联合可提高对预后评估的参考价值。     

水晶兰苷对破骨细胞生成的抑制作用

目的探讨巴戟天提取物水晶兰苷对破骨细胞生成的抑制作用。方法将RAW264.7细胞系接种于含有10%胎牛血清的杜贝克改良伊格尔培养基(DMEM)中,分为A组、B组、C组、D组,均加入核因子κB受体活化因子配体(RANKL)和巨噬细胞集落刺激因子(M-CSF),B组、C组、D组分别加入水晶兰苷药液(浓度分别为10,20,50μmol/L),连续培养3 d。采用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)比色法测定不同浓度水晶兰苷药液对破骨细胞生成的毒性影响,采用抗酒石酸酸性磷酸酶(TRAP)染色法测定不同浓度水晶兰苷药液对破骨细胞生成的影响,采用实时荧光定量(RT-qPCR)法、蛋白质印迹(WB)法测定破骨细胞关键转录因子活化T细胞核因子1(NFATc1)的mRNA和蛋白表达水平。结果MTT结果显示,各组光密度值(OD值)均在1.25~1.28之间,组间无明显差异(P>0.05);B组、C组、D组TRAP染色细胞数分别为(87.88±8.52)个、(50.38±11.78)个、(25.88±7.81)个,均明显低于A组的(132.10±11.28)个(P<0.05),且在限定浓度范围内与剂量呈正相关;B组、C组、D组NFATc1的mRNA表达水平随水晶兰苷浓度的升高而降低,与A组比较,C组和D组有显著差异(P<0.05);WB试验结果与mRNA表达水平相符。结论水晶兰苷在体外试验中可能是通过降低NFATc1的表达水平来抑制破骨细胞的生成。     

丹酚酸B对MPP+所致线粒体损伤PC12细胞的保护作用

目的 研究丹酚酸B(salvianolic acid B, SalB)对1-甲基-4-苯基吡啶离子(1-methyl-4-phenylpyridinium, MPP₊)所致PC12细胞线粒体损伤的保护作用及相关机制。方法 使用MPP 处理PC12细胞建立损伤模型,线粒体膜电位和线粒体ATP合成被用于检测线粒体功能,使用PCR检测线粒体DNA、PGC-1、NRF-1和TFAM基因表达,蛋白免疫印迹用于检测线粒体融合相关蛋白表达变化。结果 ①SalB显著减轻MPP 所致线粒体膜电位下降和线粒体ATP合成减少。②SalB明显增加MPP 处理后线粒体DNA、PGC-1、NRF-1和TFAM基因表达。③SalB增加MPP 处理后Opa-1和Mfn-1表达,而抑制Drp-1和Fis-1的表达。结论 SalB可能通过调控线粒体生物发生和线粒体融合相关蛋白对MPP 所致PC12细胞线粒体损伤发挥保护作用。     

MicroRNA-370 directly targets FOXM1 to inhibit cell growth and metastasis in osteosarcoma cells

MicroRNAs (miRNAs) are endogenous, non-coding, small RNAs, which play a critical role in regulating varieties of the biological and pathologic processes. Several reports have indicated that miR-370 acts as a tumor suppressor in varieties of tumors. However, the roles of miR-370 in osteosarcoma have not been reported. In this study, our objective was to explore the biological functions and its molecular mechanism of miR-370 in osteosarcoma cell lines, finding a therapeutic target of osteosarcoma. Our data demonstrated that miR-370 was evidently reduced in osteosarcoma cell lines, whereas FOXM1 expression was markedly increased. Up-regulation of miR-370 suppressed proliferation, arrested cell cycle and induced apoptosis in osteosarcoma cells. Besides, invasion and EMT of osteosarcoma cells was also inhibited by introduction of miR-370. Next, we found that FOXM1 expression was significantly reduced by up-regulation of miR-370. Bioinformatics analysis predicted that the FOXM1 was a potential target gene of miR-370. Luciferase reporter assay further confirmed that miR-370 could directly target the 3’ UTR of FOXM1. Overexpression of FOXM1 in osteosarcoma cells transfected with miR-370 mimic partially reversed the effects of miR-370. In conclusion, miR-370 inhibited cell growth and metastasis in osteosarcoma cells by down-regulation of FOXM1.     

部队青年军人原发性高血压临床特点及相关因素

正高血压是脑卒中、冠心病的主要相关因素,严重危害人类健康,作为心血管科的常见病和多发病,多见于老年群体中。中国高血压调查最新数据显示,2012～2015年我国18岁以上居民高血压患病率为27.9%(标准化率23.2%)~([1])。近年来多项研究数据表明,我国高血压发病的年龄呈现年轻化,青年高血压患病率10年间增长了5.1%,而且发病率还在不断上升,其增高趋势比老年人更为明显~([2])。部队青年作     

轻度二氧化碳潴留慢性阻塞性肺疾病肺功能和CT的特征

目的探讨轻度CO₂潴留慢性阻塞性肺疾病人群的肺功及影像特征,为监测和治疗提供依据。 方法选择147例慢性阻塞性肺疾病急性加重期患者,分为非CO₂潴留组61例PaCO₂＝40～44.9 mmHg;轻度CO₂潴留组48例PaCO₂＝45～50 mmHg;呼吸衰竭组38例PaCO₂>50 mmHg,比较3组在肺功能和容积CT参数的异同。 结果轻度潴留组在肺功能参数如一秒率(FEV₁%pred)等和肺气肿参数如肺气肿平均密度(MED)、肺密度分布直方图中第15百分位点所对应的CT值(PD15)等,与呼吸衰竭组存在明显差异(P<0.05),与非潴留组无统计学差异(P>0.05)。spearman相关分析显示PaCO₂与FEV₁%Pred、FVC%pred呈中度负相关(r分别是-0.536,-0.576,P<0.001),与PD15和MED存在弱负相关(r＝-0.325,P＝0.002)。 结论轻度CO₂潴留COPD肺结构和功能特征与非潴留COPD相似;呼吸衰竭组COPD具有更严重的病理和肺功能损害;CO₂轻度潴留向Ⅱ型呼吸衰竭进展中,FEV₁%pred等肺功能指标联合PD15和MED影像参数从功能和结构上能更好地反应病情。     

Thermal Ablation Damage Analysis of CFRP Suffering from Lightning Based on Principles of Tomography

Coupled electrical–thermal finite element analysis (FEA) models are widely adopted to analyze the thermal ablation damage of carbon fiber reinforced polymer (CFRP) caused by lightning, but it is still difficult to analyze the ablation due to its complex space geometry. According to the principle of computerized tomography (CT), tomographic images of FEA models’ temperature fields with different thicknesses were obtained to calculate the mass loss and compare the damage morphology. The four areas including Area 0, Area I, Area II, and Area III; were separated from the temperature fields in terms of different vaporization and pyrolysis temperature ranges of carbon fiber (CF) and resin matrix. Ablation mass losses were calculated by pixel statistics and tomographic intervals, which were consistent with the experimental results. The maximum ablation area of unprotected CFRP was found on the tomography images of 50 μm rather than the surface by comparing tomographic images with different thickness due to the influence of the thermal radiation, but this effect was not found in CFRP protected by copper mesh. Some other phenomena, including continuous evolutions of ablation areas and the influence of the intersection angle on the direction of the ablation extension, were also discovered.     

A Novel Micro-Displacement Sensor Based on Double Optical Fiber Probes Made through Photopolymer Materials

In this paper, a novel micro-displacement sensor with double optical fiber probes is proposed and designed, which can realize the highly sensitive sensing of longitudinal or lateral micro-displacements. The optical fiber probes are made through photopolymer formulation, and the effects of reaction time and optical power on the growth length of the probe are illustrated. The relationship between light intensity and longitudinal micro-displacement is a power function in the range of 0–100 μm at room temperature with a correlation coefficient of 98.92%. For lateral micro-displacement, the sensitivity is −2.9697 dBm/μm in the range of 0–6 μm with a linear fit of 99.61%. In addition, the linear correlation coefficient decreases as the initial longitudinal distance increases, and the function of these correlation coefficients is also linear with a linearity of 96.14%. This sensor has a simple manufacturing process, low cost, high sensitivity, and fast response speed. It is suitable for harsh environments such as strong electromagnetic interference and corrosivity, and has a broad application prospect in the field of micro-displacement sensing.