The Frequency and Clinical Implication of ROS1 and RET Rearrangements in Resected Stage IIIA-N2 Non-Small Cell Lung Cancer Patients

To evaluate the frequency and clinicopathological features of ROS1 and RET rearrangements in N2 node positive stage IIIA (IIIA-N2) non-small cell lung cancer (NSCLC) patients, we retrospectively screened 204 cases with a tissue microarray (TMA) panel by fluorescent in situ hybridization (FISH), and confirmed by direct sequencing and immunohistochemistry (IHC). The relationship between ROS1 or RET rearrangements, clinicopathological features, and prognostic factors were analyzed in resected stage IIIA-N2 NSCLC. Of the 204 cases, 4 cases were confirmed with ROS1 rearrangement, but no RET rearrangement was detected. All 4 ROS1-rearranged cases were adenocarcinomas. The predominant pathological type was acinar pattern in ROS1-rearranged tumors, except for 1 case harboring a mixture acinar and mucous tumor cells. Variants of ROS1 rearrangement were SDC4-ROS1 (E2:E32), SDC4-ROS1 (E4:E32) and SDC4-ROS1 (E4:E34). There was no significant association between ROS1 rearrangement and clinicopathological characteristics. In this cohort, multivariate analysis for overall survival (OS) indicated that squamous cell carcinoma and lobectomy were independent predictors of poor prognosis; R0 surgical resection and non-pleural invasion were independent predictors of good prognosis. In resected stage IIIA-N2 NSCLC patients, ROS1-rearranged cases tended to occur in younger patients with adenocarcinomas. The prognosis of resected stage IIIA-N2 is generally considered poor, but patients with ROS1 rearrangement will benefit from the targeted therapy.     

拟南芥AtR8 lncRNA对盐胁迫响应及其对种子萌发的调节作用

长链非编码RNA (lncRNA)是一类长度大于200个核苷酸且不编码蛋白质的非编码RNA, 主要由RNA聚合酶II转录生成, 大量存在于生物体内并具有多种生物学功能。AtR8 lncRNA是拟南芥(Arabidopsis thaliana)中RNA聚合酶III转录的长链非编码RNA。前期研究发现, 水杨酸(SA)处理诱导萌发种子中AtR8 lncRNA的表达, AtR8 lncRNA缺失抑制SA胁迫下的种子萌发。进一步研究发现, AtR8 lncRNA转录区域内存在保守的盐胁迫响应元件(TCTTCTTCTTTA); NaCl处理抑制萌发种子中AtR8 lncRNA的表达; 与野生型相比, 高浓度NaCl处理明显抑制了atr8 (AtR8 lncRNA部分缺失型拟南芥)种子萌发。研究结果表明, AtR8 lncRNA在拟南芥种子萌发期的盐胁迫中起重要作用。     

Comparison of the pyrolysis behavior of lignins from different tree species

Despite the increasing importance of biomass pyrolysis, little is known about the pyrolysis behavior of lignin—one of the main components of biomass—due to its structural complexity and the difficulty in its isolation. In the present study, we extracted lignins from Manchurian ash (Fraxinus mandschurica) and Mongolian Scots pine (Pinus sylvestris var. mongolica) using the Bjorkman procedure, which has little effect on the structure of lignin. Fourier transform infrared (FTIR) spectrometry was used to characterize the microstructure of the Bjorkman lignins, i.e., milled wood lignins (MWLs), from the different tree species. The pyrolysis characteristics of MWLs were investigated using a thermogravimetric analyzer, and the release of the main volatile and gaseous products of pyrolysis were detected by FTIR spectroscopy. During the pyrolysis process, MWLs underwent thermo-degradation over a wide temperature range. Manchurian ash MWL showed a much higher thermal degradation rate than Mongolian Scots pine MWL in the temperature range from 290–430 °C. High residue yields were achieved at 37 wt.% for Mongolian Scots pine MWL and 26 wt.% for Manchurian ash MWL. In order to further investigate the mechanisms of lignin pyrolysis, we also analyzed the FTIR profiles for the main pyrolysis products (CO₂, CO, methane, methanol, phenols and formaldehyde) and investigated the variation in pyrolysis products between the different MWLs.     

间充质干细胞体外调控骨髓造血前体细胞向单核系分化

研究间充质干细胞(MSC)能否在体外调控造血。体外分离培养人骨髓来源的MSC,RT-PCR检测其造血生长因子的表达,并以其为饲养层细胞,接种骨髓单个核细胞(MNC),观察生长情况,并通过形态学观察和流式细胞术分析,鉴定细胞来源和分化方向。结果显示,MSC构成性表达SCF、Flt3L和M-CSF,不表达C-CSF和GM-CSF,在骨髓MNC和MSC共培养体系中,大约2周左右可以看到大量的圆形细胞粘附在梭型MSC上生长,细胞胞体为圆形,胞浆较丰富,胞核为圆形、半月型或肾型,部分细胞呈典型的单核细胞形态,流式细胞术分析该类细胞表达CDl4,不表达CDl5、CD41、glycophorin A、CD5和CDl9。表明不需要添加外源性造血生长因子,间充质干细胞能在体外调控骨髓造血前体细胞向单核系分化,其定向分化可能与MSC分泌造血生长因子及MSC与造血细胞间相互作用有关。     

接种植物乳杆菌(Lactobacillus plantarum)对小规模饲料稻青贮品质的影响

【目的】研究接种植物乳杆菌对小规模饲料稻品质的影响。【方法】以自然发酵的样品为对照,接种不同来源植物乳酸菌发酵饲料稻,发酵30 d后对饲料稻的感官进行评价;通过选择性平板对饲料稻青贮中的不同微生物进行计数;并采用V-Score评价法对发酵品质进行评定。【结果】相对自然发酵的样品而言,接种植物乳杆菌的青贮样品感官评分等级达到优良;乳酸菌为优势菌株,引起腐败变质的好氧菌、霉菌、大肠杆菌等受到抑制;接种发酵的样品中乳酸含量明显增加,氨态氮的产生量为对照的1/2左右,V-Score评分为满分。【结论】供试的植物乳杆菌,尤其是从青饲料和青贮材料中分离的菌株能有效改善饲料稻青贮的品质,可考虑用作青贮饲料稻发酵剂。     

异叶三宝木的二萜成分及抗菌活性研究

为研究异叶三宝木(Trigonostemon heterophyllus)的二萜成分及其抗菌活性,采用硅胶柱层析、凝胶柱层析、高效液相色谱对萃取物进行分离纯化,结合现代波谱技术对所得化合物进行结构鉴定,并通过牛津杯法和2倍稀释法检测化合物对革兰氏阴性菌大肠杆菌(Escherichia coli)以及革兰氏阳性菌肺炎双球菌(Pneumococcus)的生长抑制活性和MIC值。从异叶三宝木中分离得到了6个化合物,包括5个二萜类, 1个木脂素类,分别鉴定为trigonochinene E (1)、neoboutomannin (2)、6,9-O- dedimethyltrigonostemone (3)、stelltian B (4)、3,4-secosonderianol (5)、biondinin A (6)。化合物1、2、3、5对大肠杆菌有抑制作用,MIC值分别为9.375、18.75、18.75、18.75 μg/mL。化合物2、3、4、6为首次从该种植物中分离得到,化合物4为首次从该属植物中分离得到。除化合物4外,其他化合物都有一定的抗菌活性,且化合物1、2、3对大肠杆菌抑制作用强于阳性对照硫酸卡那霉素。     

伯克霍尔德氏菌(Burkholderia sp.)2-萘酸单加氧酶基因(nmo)的克隆及表达

通过酶切连接将Burkholderia sp．JTl500的一段DNA片段(4．8kb)亚克隆到表达载体pUC18上,得到重组子pEKl23。测序后的pEKl23重组子4．8kb插入片段的序列已经登陆欧洲EMBL基因库,序列接受号为AJ566333。对这一DNA片段的序列分析显示,此DNA片段含有3个阅读框,且在这3个阅读框5’端发现一启动子特异序列。再用酶切连接方法得到仅含一个阅读框的重组子pXK3,其阅读框长度为1158bp,编码386个氨基酸,与已报道的Ralstonia eutropha HF39羟化酶(单加氧酶,bec)氨基酸序列有64％的同源性。pEKl23对2-萘酸代谢途径中4个关键底物的转化实验结果显示,其基因产物仅对2-萘酸发生加氧转化反应,而且2-萘酸浓度有明显的降低,证实此基因是2-萘酸单加氧酶基因(nmo)。同时发现其基因产物也可以转化苯甲酸钠。该酶对苯甲酸的加氧转化途径正在研究中。SDS-PAGE结果表明,pXK3、pEKl23两重组子中2-萘酸单加氧酶表达量并没明显区别,但加氧酶酶活却存在显著的差别。推测在启动子后,单加氧酶阅读框前的两个阅读框的基因产物,对单加氧酶活有促进作用。     

野油菜黄单胞菌分泌组双向电泳样品制备方法的建立

野油菜黄单胞菌野油菜致病变种(Xanthomonas campestris pv.campestris,Xcc)是十字花科植物黑腐病的病原细菌。我们建立了Xcc的蛋白质组学研究平台,用于分离、鉴定该菌的致病相关蛋白。为了减少胞外多糖(exopolysaccharide,EPS)对蛋白材料质量的影响,我们构建了EPS缺陷的Xcc8004ΔgumB突变体。本研究以Xcc8004ΔgumB出发菌株,用诱导培养液培养,取细胞上清通过超滤浓缩得到蛋白质粗提物,分别采用丙酮沉淀法、试剂盒纯化法和丙酮沉淀-试剂盒联用法来纯化蛋白质粗提物,通过比较双向电泳的结果优选最佳的样品制备方法。结果证明丙酮沉淀-试剂盒联用法较为理想,所得双向电泳图片清晰,分辨率高。因此,此方法可以用于制备野油菜黄单胞菌分泌组双向电泳样品,并可以满足进一步研究的需要。     

Cyclo-hexa-peptides at the water/cyclohexane interface: a molecular dynamics simulation

Molecular dynamic (MD) simulations have been performed to study the behaviors of ten kinds of cyclo-hexa-peptides (CHPs) composed of amino acids with the diverse hydrophilic/hydrophobic side chains at the water/cyclohexane interface. All the CHPs take the “horse-saddle” conformations at the interface and the hydrophilicity/hydrophobicity of the side chains influences the backbones’ structural deformations. The orientations and distributions of the CHPs at the interface and the differences of interaction energies (ΔΔE) between the CHPs and the two liquid phases have been determined. RDF analysis shows that the H-bonds were formed between the O_C atoms of the CHPs’ backbones and H_w atoms of water molecules. N atoms of the CHPs’ backbones formed the H-bonds or van der Waals interactions with the water solvent. It was found that there is a parallel relationship between ΔΔE and the lateral diffusion coefficients (D _xy ) of the CHPs at the interface. The movements of water molecules close to the interface are confined to some extent, indicating that the dynamics of the CHPs and interfacial water molecules are strongly coupled.