中青年人群非酒精性脂肪肝发生风险预测模型的建立

目的建立非酒精性脂肪肝(NAFLD)的发生风险预测模型,为NAFLD的预防及发生提供管理策略。方法选取2015年1月至2018年7月大连医科大学附属第二医院健康管理中心年度体检数据库中18~59岁、至少有2次连续体检记录、基线未发生NAFLD且无重要指标缺失者的数据,观察结局为NAFLD。收集基本信息、体格检查、实验室检查和腹部超声检查资料,将所有研究对象随机分为建模组和验证组。采用SPSS 23.0进行χ²检验、t检验、秩和检验、单因素Cox回归分析。利用建模组资料进行多因素Cox回归分析选取预测指标,用RStudio软件绘制线图,构建NAFLD发生风险预测模型。通过一致性指数(C指数)和校正曲线对建模组和验证组模型的预测效果进行验证。结果本研究共纳入2377名研究对象,其中建模组1585人,验证组792人。本研究共有467人发生NAFLD(累积发病率为19.6%),平均随访时间为(27.06±8.02)个月。其中,建模组NAFLD发病人数为310人(发病率为19.6%),验证组NAFLD发病人数为157人(累积发病率为19.8%)。多因素Cox回归分析结果显示,高密度脂蛋白胆固醇水平(HR=0.334,95%CI:0.209~0.534)为NAFLD发病的独立保护因素,而体质指数(HR=1.220,95%CI:1.172~1.271)、甘油三酯(HR=1.114,95%CI:1.052~1.180)、低密度脂蛋白胆固醇(HR=1.252,95%CI:1.054~1.487)、丙氨酸氨基转移酶(HR=1.013,95%CI:1.005~1.021)、血尿酸(HR=1.003,95%CI:1.001~1.004)为NAFLD发病的独立危险因素(P<0.05,P<0.01)。利用上述影响因素成功构建NAFLD发生风险预测模型。建模组和验证组的C指数分别为0.789(95%CI:0.766~0.812)、0.777(95%CI:0.742~0.812),校正曲线显示模型预测结果与实际观察结果吻合良好。结论本研究构建的NAFLD发生风险预测模型可以准确地预测NAFLD的发生概率,为早期识别NAFLD高危人群提供新思路。     

再治疗根管粪肠球菌毒力因子gelE表达与临床表现的关系研究

目的:比较再治疗根管内粪肠球菌(enterococcus faecalis)毒力因子gelE表达情况,分析gelE表达与临床表现的关系。方法:采集临床需要根管再治疗病例的根管内细菌样本53例,利用Real Time Quantitative PCR技术来检测gelE的表达情况。统计学分析gelE表达与患者临床表现之间的关系。结果:再治疗根管内粪肠球菌毒力因子gelE在有临床症状或体征和有根尖暗影的病例中表达增强(P<0.05)。结论:再治疗根管内粪肠球菌毒力因子gelE的表达增强与临床症状或体征的出现有关系。     

Identification of two SNPs in myostatin (MSTN) gene of Takifugu rubripes and their association with growth traits

The myostatin (MSTN) is a member of transforming growth factor-β superfamily which inhibits muscle growth. In this study, the genomic DNA sequence of MSTN gene was cloned from Takifugu rubripes (T. rubripes). Two polymorphisms of the MSTN gene were detected by polymerase chain reaction-single strand conformation polymorphism (PCR–SSCP) and DNA sequencing methods in 296 T. rubripes. One A748G locates in exon 2 and the other, C1197T, in intron 2. Analysis showed that the A748G mutation caused an amino acid change from Thr to Ala (Ala166Glu). These two SNPs showed a low degree of linkage disequilibrium and four haplotypes were identified. The most frequent haplotype was AC, which occurred at a frequency of 44.3%. Association analyses between these two SNPs and growth traits showed that the individuals with genotype CT and TT of the mutation C1197T had significantly higher body mass, body length and body height than those with genotype CC (P < 0.05). These results show that MSTN gene can be utilized as a candidate gene for molecular marker-assisted breeding of T. rubripes.     

3D Pd/Co core–shell nanoneedle arrays as a high-performance cathode catalyst layer for AAEMFCs

A novel cathode architecture using vertically aligned Co nanoneedle arrays as an ordered support for application in alkaline anion-exchange membrane fuel cells (AAEMFCs) has been developed. The Co nanoneedle arrays were directly grown on a stainless steel sheet via a hydrothermal reaction and then a Pd layer was deposited on the surface of the Co nanoneedle arrays using a vacuum sputter-deposition method to form Pd/Co nanoneedle arrays. After transferring the Pd/Co nanoneedle arrays to an AAEM, a cathode catalyst layer was formed. Without the use of an alkaline ionomer, the AAEMFC with the prepared cathode catalyst layer showed an enhanced performance with ultra-low Pd loading of down to 33.5 μg cm⁻², which is much higher than the conventionally used cathode electrode with a Pt loading of 100 μg cm⁻². This is the first report where three-dimensional Co nanoneedle arrays have been used as the cathode support in an AAEMFC, which is able to deliver a higher power density without an alkaline ionomer than that of conventional membrane electrode assembly (MEA).

A novel ordered Pd/Co nanoneedle array was used as a cathode in an AAEMFC and delivered a higher power density than that of conventional MEA.     

超声靶向破坏微泡技术介导小鼠肝癌细胞株JNK1基因表达、细胞迁移和侵袭抑制

目的: 探讨应用超声靶向破坏微泡 (UTMD) 技术介导小鼠肝癌细胞株JNK1基因的表达、细胞迁移和侵袭抑制的作用,阐明其作用机制。方法: 构建并筛选RNA干扰效果最好的短发夹RNA(shRNA)。将小鼠肝癌细胞株Hca-F分为正常Hca-F细胞组、shRNA质粒组、脂质体组、超声微泡结合超声辐照组及脂质体结合超声微泡加超声辐照组。采用倒置荧光显微镜观察各组细胞转染率,荧光定量PCR和Western blotting 法检测JNK1基因mRNA和蛋白表达水平,CCK-8法检测各组细胞的细胞活性,应用Transwell 实验检测各组细胞的体外迁移能力。结果: 脂质体结合超声微泡加超声辐照组细胞转染率高于shRNA质粒组、脂质体组和超声微泡结合超声辐照组(均P<0.05),脂质体组和超声微泡结合超声辐照组比较差异无统计学意义(P>0.05)。脂质体结合超声微泡加超声辐照组JNK1 mRNA和蛋白表达水平低于其他各组(P<0.05);脂质体结合超声微泡加超声辐照组细胞活性和平均穿膜细胞数均低于其他各组(P<0.05)。结论: UTMD技术结合脂质体转染法可以提高小鼠肝癌细胞株JNK1 shRNA的转染效率,增强其对基因表达、细胞活力、迁移和侵袭能力的抑制。     

Enhanced efficiency of Cu2ZnSn(S,Se)4 solar cells via anti-reflectance properties and surface passivation by atomic layer deposited aluminum oxide

Reducing interface recombination losses is one of the major challenges in developing Cu₂ZnSn(S,Se)₄ (CZTSSe) solar cells. Here, we propose a CZTSSe solar cell with an atomic layer deposited Al₂O₃ thin film for surface passivation. The influence of passivation layer thickness on the power conversion efficiency (PCE), short-circuit current density (J_sc), open-circuit voltage (V_oc) and fill factor (FF) of the solar cell is systematically investigated. It is found that the Al₂O₃ film presents notable antireflection (AR) properties over a broad range of wavelengths (350–1000 nm) for CZTSSe solar cells. With increasing Al₂O₃ thickness (1–10 nm), the average reflectance of the CZTSSe film decreases from 12.9% to 9.6%, compared with the average reflectance of 13.6% for the CZTSSe film without Al₂O₃. The Al₂O₃ passivation layer also contributes to suppressed surface recombination and enhanced carrier separation. Passivation performance is related to chemical and field effect passivation, which is due to released H atoms from the Al–OH bonds and the formation of Al vacancies and O interstitials within Al₂O₃ films. Therefore, the J_sc and V_oc of the CZTSSe solar cell with 2 nm-Al₂O₃ were increased by 37.8% and 57.8%, respectively, in comparison with those of the unpassivated sample. An optimal CZTSSe solar cell was obtained with a V_oc, J_sc and η of 0.361 V, 33.78 mA and 5.66%. Our results indicate that Al₂O₃ films show the dual functions of AR and surface passivation for photovoltaic applications.

ALD-Al₂O₃ is used as a passivation layer in a CZTSSe device and optimal device parameters are obtained by precisely controlling Al₂O₃ thickness.     

Taurine improves neuron injuries and cognitive impairment in a mouse Parkinson’s disease model through inhibition of microglial activation

Clinical and experimental findings support the view that activation of hippocampus microglia through NADPH oxidase contributes to cognitive impairment in Parkinson's disease (PD). Taurine, an antioxidant, displays an exclusive physical property on brain function, such as learning and memory. To date, the role of taurine in improving cognitive impairment in PD is not fully uncovered. Hence, we evaluated the protective effect of taurine on cognitive ability and explored the related mechanism in the model built by paraquat and maneb (P + M)-induced PD mice. Then the ability of learning and memory was observed by Morris water maze, neuron loss was evaluated by immunohistochemistry in hippocampus, the level of postsynaptic density 95 (PSD95) and microglia activation was assessed by immunostaining, the molecules (gp91^phox, p47^phox, mac1, p-Src/Src and p-Erk/Erk) were examined by western blot. The results showed that taurine could alleviate the impairments in learning and memory induced by P + M injection in mice (decreased escape latency on day 4, P < 0.01; decreased swimming distance on day 4, P < 0.05; increased percent time in target quadrant, P < 0.05), corresponding with activation of microglia (decreased IBa-1 density, P < 0.001; decreased the protein expression of p47^phox, P < 0.05; decreased protein expression of gp91^phox, P < 0.01; decreased p-Src/Src, P < 0.01; decreased p-Erk/Erk, P < 0.01; decreased mac 1, P < 0.01), decreased neuron loss (increased number of NeurN⁺ neuron, P < 0.001; increased protein expression of NeruN, P < 0.01; decreased protein expression of caspase 3, P < 0.01) and increased PSD95 level in hippocampus (P < 0.01). The results indicated that mac1 and Src-Erk signaling was involved in increased NADPH oxidase expression in hippocampus microglia of P + M mice, and taurine could improve injuries in learning and memory through mac1 reduction. The new findings in mac1 triggering hippocampal microglia NADPH oxidase through Src/Erk pathway of the present study might provide a therapy target for PD.     

Carbazole‐Substituted Triphenylamine and Diketopyrrolopyrrole Alternating Copolymer for Photovoltaic Cells

A new alternating conjugated polymer (PTCDPP) of carbazole‐substituted triarylamine and diketopyrrolopyrrole is prepared and characterized in detail. The polymer exhibits two strong absorption bands at 345 and 600 nm. With highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of ?5.13 eV and ?3.67 eV, PTCDPP displays an energy gap of 1.66 eV. PTCDPP‐based bulk heterojunction solar cells with a structure of fluorinated tin oxide (FTO)/TiO₂/PTCDPP:[6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM)/MoO₃/Ag are fabricated. The devices are optimized by adjusting the composition of the PTCDPP:PCBM active layer, thermal treatment, and addition of processing additives. The device based on PTCDPP:PCBM (1:4, w/w) shows a power conversion efficiency (PCE) of 2.31%, with a short‐circuit current of 4.17 mA cm^?2, an open‐circuit voltage of 0.79 V, and a fill factor of 0.35. The best cell performance (2.65% PCE) is achieved by using 1,8‐diiodooctane (3%, v/v) as a processing additive and annealing the active layer at 80 °C.