基于CiteSpace的金花茶研究知识图谱分析

对金花茶研究领域的文献信息进行知识图谱可视化分析,可以为研究者准确把握该领域的研究进展提供理论参考。该文利用引文分析软件CiteSpace对1979年—2018年金花茶的相关研究成果进行了计量学和可视化分析,绘制知识图谱,揭示金花茶研究的发展和知识结构。结果表明:(1)金花茶的研究逐渐被重视,年均研究文献逐渐增多;载文期刊的所在地主要为广西。(2)虽已形成核心作者群,但核心作者团队之间合作并不紧密;研究机构集中在广西,已形成"研究机构-高校-企业"的合作方式。(3)研究主要经历了三个阶段,即起步探索期(1979年—1985年)、平稳发展期(1986年—2006年)和快速增长期(2007年—2018年)。(4)金花茶化学成分、繁殖技术以及产品研发的研究正在发展为新前沿。金花茶研究中存在一些问题亟需解决,建议加强对金花茶研究的重视,围绕现实需求深入开展金花茶研究,以实现生态与经济协调发展。     

Salivary MicroRNAs as Promising Biomarkers for Detection of Esophageal Cancer

Background and Purpose

Tissue microRNAs (miRNAs) can detect cancers and predict prognosis. Several recent studies reported that tissue, plasma, and saliva miRNAs share similar expression profiles. In this study, we investigated the discriminatory power of salivary miRNAs (including whole saliva and saliva supernatant) for detection of esophageal cancer.

Materials and Methods

By Agilent microarray, six deregulated miRNAs from whole saliva samples from seven patients with esophageal cancer and three healthy controls were selected. The six selected miRNAs were subjected to validation of their expression levels by RT-qPCR using both whole saliva and saliva supernatant samples from an independent set of 39 patients with esophageal cancer and 19 healthy controls.

Results

Six miRNAs (miR-10b*, miR-144, miR-21, miR-451, miR-486-5p, and miR-634) were identified as targets by Agilent microarray. After validation by RT-qPCR, miR-10b*, miR-144, and miR-451 in whole saliva and miR-10b*, miR-144, miR-21, and miR-451 in saliva supernatant were significantly upregulated in patients, with sensitivities of 89.7, 92.3, 84.6, 79.5, 43.6, 89.7, and 51.3% and specificities of 57.9, 47.4, 57.9%, 57.9, 89.5, 47.4, and 84.2%, respectively.

Conclusions

We found distinctive miRNAs for esophageal cancer in both whole saliva and saliva supernatant. These miRNAs possess discriminatory power for detection of esophageal cancer. Because saliva collection is noninvasive and convenient, salivary miRNAs show great promise as biomarkers for detection of esophageal cancer in areas at high risk.     

基于优化的最大熵模型预测中国高山栎组植物的历史、现状与未来分布变化

气候变化影响着植物物种的地理分布,预测物种潜在适生区对认识其地理分布特征及发挥其生态价值与经济价值具有重要意义。以高山栎组植物为研究对象,运用R语言ENMeval数据包调整调控倍频（RM）和特征组合（FC）优化的最大熵（MaxEnt）模型和ArcGIS软件,基于160条高山栎组植物分布点记录和22个环境因子进行潜在适生区预测,探讨影响其地理分布的主要环境因子,同时预测其在末次间冰期（Last interglacial,LIG）、末次盛冰期（Last glacial maximum,LGM）、全新世中期（Mid Holocene,MH）、当代（Current）、2041-2060年（2050年）和2061-2080年（2070年）3种不同CO₂浓度排放路径下潜在适生区的空间分布格局及其质心变化趋势。结果表明：最优模型参数RM=2.5,FC=LQHPT时,MaxEnt模型复杂度和过拟合程度最低,模型预测准确性极高,AUC=0.960±0.15。综合刀切法贡献率、置换贡献率和单因子响应曲线可知影响其地理分布的主要环境因子是气温季节性变动系数（bio4）、高程（dem）、年降水量（bio12）和等温性（bio3）,其适宜范围分别为435-625、1792-3978m、670-1050mm和41.5-50.3,累计贡献率高达81.6%,其中温度是影响高山栎组植物最重要的环境因子。当前气候条件下,高山栎组植物总适生区面积62.37×10⁴km²,高适生区面积10.47×10⁴km²,占总适生区面积的16.79%,集中分布于川滇横断山地区、滇中高原北部、藏东南以及黔西部分地区。各个时期间高山栎组植物的适生区面积差异较大,当代潜在适生区面积最小且破碎化最严重,可能由于气候变化及人类影响所致。未来各个时期潜在分布区面积均有增大的趋势,但RCP8.5情景下面积相较于其他情景有所降低,表明全球气候变暖背景下不利于高山栎组植物的长期生长。同时,质心分析表明未来气候条件下其分布有向低海拔和低纬度迁移的趋势。     

Superresolution characterization of core centriole architecture

The centrosome is the main microtubule-organizing center in animal cells. It comprises of two centrioles and the surrounding pericentriolar material. Protein organization at the outer layer of the centriole and outward has been studied extensively; however, an overall picture of the protein architecture at the centriole core has been missing. Here we report a direct view of Drosophila centriolar proteins at ∼50-nm resolution. This reveals a Sas6 ring at the C-terminus, where it overlaps with the C-terminus of Cep135. The ninefold symmetrical pattern of Cep135 is further conveyed through Ana1–Asterless axes that extend past the microtubule wall from between the blades. Ana3 and Rcd4, whose termini are close to Cep135, are arranged in ninefold symmetry that does not match the above axes. During centriole biogenesis, Ana3 and Rcd4 are sequentially loaded on the newly formed centriole and are required for centriole-to-centrosome conversion through recruiting the Cep135–Ana1–Asterless complex. Together, our results provide a spatiotemporal map of the centriole core and implications of how the structure might be built.     

Study on polymerization effect of polyembryony genes by SSCP marker and family trees in Chinese goats

The aim of experiment was to analyze the polymerization effect of genotypes and genotype combinations of PRLR and LH?? gene loci in Xinong Saanen goat by SSCP marker and family trees. The relationships of genotype combinations and litter size were compared in Xinong Saanen goat. The results indicate that there are genetic polymorphisms at the PRLR and LH?? gene loci, and there are 4 positive genotypes (GG, CC, PP and LL) and 4 negative genotypes (HH, DD, QQ and MM) effects on litter size, respectively in Xinong Saanen goat. Compared with the other genotype combinations, the polymerization effect of GGCCPPLL markedly improved (P?<?0.05). The polymerization effect value of CC genotype was higher than that of CD genotype by 14.12%, and MM genotype was higher than that of LM genotype by 3.80%, and PP genotype was higher than that of QQ genotype by 15.67%, and LL genotype was higher than that of LM genotype by 11.48%, and PQ genotype was higher than that of QQ genotype by 11.02%, and CD genotype was higher than that of DD genotype by 10.69%, and PQ genotype was higher than that of PP genotype by 6.09%. There was significantly polymerization effect in the course of reproduction from parental generation (F0) to F1 generation. However, there was significantly gene isolation effect in the course of reproduction from F1 generation to F2 generation. This result can be used to guide the goat breeding in polyembryony trait.     

Regulation of protein kinase C inactivation by Fas-associated protein with death domain

Protein kinase C (PKC) plays important roles in diverse cellular processes. PKC has been implicated in regulating Fas-associated protein with death domain (FADD), an important adaptor protein involved in regulating death receptor-mediated apoptosis. FADD also plays an important role in non-apoptosis processes. The functional interaction of PKC and FADD in non-apoptotic processes has not been examined. In this study, we show that FADD is involved in maintaining the phosphorylation of the turn motif and hydrophobic motif in the activated conventional PKC (cPKC). A phosphoryl-mimicking mutation (S191D) in FADD (FADD-D) abolished the function of FADD in the facilitation of the turn motif and hydrophobic motif dephosphorylation of cPKC, suggesting that phosphorylation of Ser-191 negatively regulates FADD. We show that FADD interacts with PP2A, which is a major phosphatase involved in dephosphorylation of activated cPKC and FADD deficiency abolished PP2A mediated dephosphorylation of cPKC. We show that FADD deficiency leads to increased stability and activity of cPKC, which, in turn, promotes cytoskeleton reorganization, cell motility, and chemotaxis. Collectively, these results reveal a novel function of FADD in a non-apoptotic process by modulating cPKC dephosphorylation, stability, and signaling termination.     

自然越冬期姜花属植物生理指标变化及抗寒性评价

为了解姜花属(Hedychium)植物的抗寒性并筛选抗寒种质,测定了3种姜花属植物和11个品种在自然越冬过程中的相对电导率、可溶性蛋白质和MDA含量及SOD、POD活性的变化,采用主成分分析结合隶属函数法对姜花属植物抗寒性进行综合评价及聚类分析.结果表明,姜花属植物的5个生理指标随越冬时间的延长均呈先上升后下降的变化趋...     

产石杉碱甲内生真菌的复壮及产量提高研究

【目的】千层塔中分离得到的内生真菌胶孢炭疽Cg01可合成石杉碱甲(huperzine A, HupA),但产量较低,且随着继代的增加,产量下降,菌株退化严重。研究表明,表观遗传修饰与次生代谢产物的合成密切相关。本研究旨在提高HupA的产量,改善退化菌株的品质,并从表观遗传修饰的角度探讨次生代谢产物合成的机理。【方法】通过改变培养基碳源、添加生物诱导子,根据胶孢炭疽Cg01的菌落形态、菌丝生长速度、生物量及HupA产量等筛选复壮培养基;添加不同浓度的组蛋白甲基化转移酶抑制剂,检测HupA的产量,筛选提高HupA产量的小分子抑制剂;检测相关表观遗传修饰基因的表达。【结果】添加同源刺激物千层塔茎叶汁,对胶孢炭疽Cg01的菌落形态、生长速度、形态特征及生物量无显著影响,但可提高HupA的产量,传代至第5代时为对照组的1.67倍(125.7 μg/L)。添加千层塔茎叶汁能显著降低组蛋白甲基化转移酶Cg12377、组蛋白去乙酰化酶Cg15620、DNA甲基化转移酶Cg02440基因的表达,提高组蛋白去乙酰化酶Cg02312基因的表达。UNC0224对内生真菌胶孢炭疽菌的HupA产量无显著影响;2‒15 μmol/L BRD4770能显著提高HupA的产量(169.57‒152.10 μg/L)。BRD4770组处理后,相关表观遗传基因Cg12377、Cg02440、Cg02312和Cg15620的表达量都显著下降。【结论】添加千层塔茎叶汁培养胶孢炭疽Cg01可维持其合成次生代谢产物的能力;添加组蛋白甲基化转移酶抑制剂BRD4770可提高HupA的产量。本研究为解决内生真菌大规模生产过程中的菌株退化问题提供了参考,并为组蛋白甲基化影响次生代谢产物的合成提供了依据。