AKT2及磷酸化AKT2在非小细胞肺癌中的表达及临床意义

目的 研究AKT2及磷酸化AKT2(p-AKT2)在非小细胞肺癌(NSCLC)组织中的表达及临床意义.方法 应用免疫组织化学法检测137例非小细胞肺癌组织中AKT2和p-AKT2表达,分析AKT2及p-AKT2表达与肺癌预后的关系.结果 非小细胞肺癌组织中AKT2在腺癌及鳞癌组织中的阳性表达率分别为60.5%和54.1%,差异无统计学意义(P>0.05);p-AKT2在腺癌及鳞癌组织中的阳性表达率分别为68.4%和47.5%,差异有统计学意义(P<0.05).同时,本研究发现AKT2和p-AKT2的表达在患者的年龄、性别、肿瘤TNM分期及细胞分化程度等方面差异无统计学意义(P>0.05).生存分析显示,AKT2表达阳性的NSCLC患者5年生存率及中位生存时间与阴性表达者比较差异无统计学意义[36%vs.30%,(33.960±2.485)月vs.(31.338±2.868)月,P>0.05];而p-AKT2表达阳性的患者5年生存率及中位生存时间与阴性表达者比较差异有统计学意义[20%vs.56%,(28.464±2.235)月vs.(39.214±3.075)月,P<0.05].进一步分层分析发现,Ⅰ期NSCLC患者中,AKT2表达阳性者5年中位生存时间与阴性表达者比较差异无统计学意义[(34.778±4.469)月va.(40.133±5.632)月,P>0.05];而p-AKT2表达阳性的NSCLC患者5年中位生存时间与阴性表达者比较差异有统计学意义[(29.808±4.337)月vs.(47.875±4.852)月,P<0.05].结论 p-AKT2在肺腺癌中的表达高于肺鳞癌,且p-AKT2的阳性表达缩短了NsCLC患者的5年中位生存时间.     

First-trimester fetal limb biometry in Chinese population

OBJECTIVES: To establish reference ranges for fetal limb biometry obtained by transabdominal ultrasound examination at 12-14 weeks of gestation in Chinese women. METHODS: A total of 1489 normal singleton fetuses between 12(+0) and 14(+6) weeks of gestation were examined transabdominally by two experienced observers. The gestation was ascertained by measurement of fetal crown-rump length (CRL) or biparietal diameter (BPD) and head circumference (HC). The lengths of the humerus and femur were prospectively worked out. RESULTS: Gestation-specific reference ranges for limb measurements were calculated. The femur length (FL) (mean +/- SD) was 9.15 +/- 1.44 mm at 12-12(+6) weeks, 11.45 +/- 1.35 mm at 13-13(+6) weeks, and 13.64 +/- 1.60 mm at 14-14(+6) weeks; the corresponding humerus length (HL) (mean +/- SD) was 9.63 +/- 1.44 mm, 12.01 +/- 1.41 mm, 14.29 +/- 1.48 mm, respectively. CONCLUSIONS: There was a general increase in fetal limb biometry with gestation. Fetal limb length can be an early marker of early growth restriction as well as fetal skeletal dysplasia among women in the local population.     

卡马西平、丙戊酸钠、托吡酯对3～12岁癫(癎)儿童骨代谢的影响

目的探讨抗癫痫（EP）药物（AEDs）卡马西平（CBZ）、丙戊酸钠（VPA）、托吡酯（TPM）对EP患儿骨代谢影响。方法实验组为90例3～12岁原发性EP患儿,根据治疗药物不同随机分为CBZ、VPA、TPM组各30例。除口服上述药物外未予其他任何药物治疗,疗程6～12个月。于治疗前和治疗后3、6个月分别测定骨密度（BMD）、骨碱性磷酸酶（BAP）、血钙、磷、碱性磷酸酶（ALP）。对照组为30例未治疗原发性EP患儿,同期检测上述指标。对上述骨代谢指标进行评价。结果实验组治疗前后BMD、BAP、钙、磷、ALP与对照组比较无显著性差异（Pa〉0.05）。实验组CBZ、VPA、TPM治疗前后5种骨代谢指标比较亦无显著性差异（Pa〉0.05）。结论短期服用CBZ、VPA、TPM对3～12岁EP患儿骨代谢无影响。     

siRNAs against the Epstein Barr virus latency replication factor, EBNA1, inhibit its function and growth of EBV-dependent tumor cells

The Epstein Barr virus (EBV) plays a role in maintenance of the tumor phenotype in a number of human cancers. The EBV latency replication factor, EBNA1, is required for persistence of the EBV episome, is anti-apoptotic, and is universally expressed in all EBV-associated tumors. Here, we show that EBNA1-specific siRNAs can inhibit EBNA1 expression and function. siRNAs were generated against three target sites in the EBNA1 messenger RNA, and two of these were found to inhibit EBNA1 expression from an ectopic EBNA1 expression cassette. EBNA1 siRNAs also inhibit endogenously expressed EBNA1 in EBV-positive epithelial and B-cell lines. Using a mini-EBV replication model, siRNA-mediated inhibition of EBNA1 expression suppressed the episomal maintenance function of EBNA1. Lastly, introduction of an EBNA1 siRNA into an EBV-positive tumor cell line inhibited tumor cell growth/survival. These data suggest that siRNAs against EBNA1 may have therapeutic value in EBV-associated diseases.     

Ischemic preconditioning negatively regulates plenty of SH3s-mixed lineage kinase 3-Rac1 complex and c-Jun N-terminal kinase 3 signaling via activation of Akt

Activation of Akt/protein kinase B has been recently reported to play an important role in ischemic tolerance. We here demonstrate that the decreased protein expression and phosphorylation of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) underlie the increased Akt-Ser-473 phosphorylation in the hippocampal CA1 subfield in ischemic preconditioning (IPC). Co-immunoprecipitation analysis reveals that Akt physically interacts with Rac1, a small Rho family GTPase required for mixed lineage kinase 3 (MLK3) autophosphorylation, and both this interaction and Rac1-Ser-71 phosphorylation induced by Akt are promoted in preconditioned rats. In addition, we show that Akt activation results in the disassembly of the plenty of SH3s (POSH)-MLK3-Rac1 signaling complex and down-regulation of the activation of MLK3/c-Jun N-terminal kinase (JNK) pathway. Akt activation results in decreased serine phosphorylation of 14-3-3, a cytoplasmic anchor of Bax, and prevents ischemia-induced mitochondrial translocation of Bax, release of cytochrome c, and activation of caspase-3. The expression of Fas ligand is also decreased in the CA1 region. Akt activation protects against apoptotic neuronal death as shown in TUNEL staining following IPC. Intracerebral infusion of LY294002 before IPC reverses the increase in Akt phosphorylation and the decrease in JNK signaling activation, as well as the neuroprotective action of IPC. Our results suggest that activation of pro-apoptotic MLK3/JNK3 cascade can be suppressed through activating anti-apoptotic phosphoinositide 3-kinase/Akt pathway induced by a sublethal ischemic insult, which provides a functional link between Akt and the JNK family of stress-activated kinases in ischemic tolerance.     

Mitochondrial DNA mutations and mitochondrial DNA depletion in breast cancer

Somatic mutations in mitochondrial DNA (mtDNA) have been demonstrated in various tumors, including breast cancer. However, it still remains unclear whether the alterations in mtDNA are related to the clinicopathological features and/or the prognosis in the breast cancer. We analyzed somatic mutations in the D-loop region, the common 4,977-bp deletion, and the copy number of mtDNA in breast cancer and paired nontumorous breast tissues from 60 Taiwanese patients. We found that 18 of the 60 (30%) breast cancers displayed somatic mutations in mtDNA D-loop region. The incidence of the 4,977-bp deletion in nontumorous breast tissues (47%) was much higher than that in breast cancers (5%). The copy number of mtDNA was significantly decreased in 38 of the 60 (63%) breast cancers as compared to their corresponding nontumorous breast tissues (P = 0.0008). The occurrence of D-loop mutations was associated with an older onset age (>or=50 years old, P = 0.042), and tumors that lacked expressions of estrogen receptor and progesterone receptor (P = 0.024). Patients with mtDNA D-loop mutation and breast cancer had significantly poorer disease-free survival than those without mutation, when assessed by Kaplan-Meier curves and log-rank test (P = 0.005). Multivariate Cox regression analysis indicated that a D-loop mutation is a significant marker that is independent of other clinical variables and that it can be used to assess the prognosis of patients. Our findings suggest that somatic mutations in mtDNA D-loop can be used as a new molecular prognostic indicator in breast cancer.     

海藻酸钙微胶珠的载药性能优化

利用高压静电法制备了海藻酸钙微胶珠,以牛血红蛋白作为模型药物,考察了牛血红蛋白（Hb）的稳定性、制备条件对微胶珠载药的影响。结果表明：Hb在10℃下能稳定存在,1．8％（w／v）Na-Alg与4．5％（w／v）CaCl2制备的微胶珠载药量较大,真空干燥的微胶殊彼此粘连破坏严重,冷冻干燥则表面出现明显的内陷,乙醇梯度洗脱-真空干燥球形度较好。水凝胶态的微胶珠载药后球形度完好,是理想的载药方式,24h时载药量达28．4％,为干燥后的2～3倍。     

利用hBMSCs在生物反应器中构建小口径血管的实验研究

目的采用改进的生物反应器系统,应用人骨髓间充质干细胞(hBMSCs)构建小口径的组织工程血管。方法设计一套血管生物反应器系统,采用有限元方法对组织工程小血管托架材料进行分析,从而设计一套用于构建直径为2mm的小血管托架;收集人的原代骨髓基质干细胞进行体外扩增和培养,选用第3代细胞与聚羟基乙酸酯(PGA)复合后置于血管生物反应器中动态培养;培养4周后,对材料复合物取材,进行大体观察、HE染色、扫描电镜和平滑肌免疫组化等指标检测。结果血管色泽明亮,有一定的弹性,用镊子反复压下血管能够反弹恢复原样;细胞分泌的胶原基质排列较规则,免疫组化结果表明血管含有平滑肌弹性肌动蛋白的成分。结论改进的血管生物反应器能模拟血管的力学环境,并能利用hBMSCs成功构建组织工程化小血管组织。     

间充质干细胞移植修复梗死心肌的策略及效果

背景：很多研究表明间充质干细胞治疗心肌梗死具有极大的潜力。 目的：综述目前增强间充质干细胞治疗心肌梗死的移植策略及其移植后疗效评估方法。 方法：应用计算机检索PubMed、知网、维普及康健数据库中1995年1月至2012年3月关于增强间充质干细胞移植疗效的文章,在标题和摘要中以“间充质干细胞;心功、血管新生或存活”或“Mesenchymal stem cell;Fuction、Angiogenesis or Survival”为检索词进行检索。选择文章内容与运用不同的移植策略来提高间充质干细胞移植后心功恢复、心肌血管新生及移植细胞存活率这几方面有关,同一领域文献则选择近期发表在权威杂志文章。初检得到220篇文献,根据纳入标准选择20篇文章进行综述。 结果与结论：通过间充质干细胞体外扩增后诱导分化并移植是心肌梗死后重建做功心肌的具有潜力的新途径,但因其移植后心肌归巢、分化率及存活率低而应用受限。此外,采取合理方法精确评估移植疗效对后期移植策略选择也至关重要,且心脏结构功能重建、心肌纤维化减轻和毛细血管新生程度3个方面成为主要的评价标准。从心脏整体功能考虑到局部功能评估和由选择合适单成像方式成像到采取“非侵入性融合显像”是目前间充质干细胞移植疗效评价的新进步。通过采用合适的移植策略及疗效评价方法以增强间充质干细胞治疗心肌梗死疗效,值得并需要更进一步研究探讨。