Pollen Morphology of Plants from the Hengduan Mountains and Their Ecological Significance

Pollen morphology of selected taxa from the Hengduan Mountains, Southwest China are investigated in the present study. Forty eight taxa (flowering in the summer, 46 species and 2 varieties) of 43 genera belonging to 27 families were observed by light and scanning electron microscopy. Pollen morphology is described in detail. Two pollen shapes are mainly found in these species: subprolate to prolate (271%) and prolate (25%). Spheroidal, subspheroidal to subprolate, suboblate and tetrad shapes can also be found in some species. Aperture type is mostly tricolporate, with a percentage of 438, and also contains tricolpate, pantoporate, stephanocolpate, 3 colporoid, 6 colpate, monocolpate. The most common ornamentation is finely reticulate, with a percentage of 50. Other exine ornamentations, such as coarsely reticulate, finely granulate, smooth, spinulose are also observed. The palynological documentation of these species will provide the modern palynological basis for paleopalynological studies of the Quaternary Strata. On the basis of pollen morphology characters, identification features of some species in the same families were discussed according to the results of cluster analysis used by SPSS. The ecological significance was also discussed based on the ecological properties of these taxa.     

On the statistical significance of protein complex

Background: Statistical validation of predicted complexes is a fundamental issue in proteomics and bioinformatics. The target is to measure the statistical significance of each predicted complex in terms of p-values. Surprisingly, this issue has not received much attention in the literature. To our knowledge, only a few research efforts have been made towards this direction. Methods: In this article, we propose a novel method for calculating the p-value of a predicted complex. The null hypothesis is that there is no difference between the number of edges in target protein complex and that in the random null model. In addition, we assume that a true protein complex must be a connected subgraph. Based on this null hypothesis, we present an algorithm to compute the p-value of a given predicted complex. Results: We test our method on five benchmark data sets to evaluate its effectiveness. Conclusions: The experimental results show that our method is superior to the state-of-the-art algorithms on assessing the statistical significance of candidate protein complexes.     

Challenges in assessing pathogenicity based on frequency of variants in mismatch repair genes: an extreme case of a MSH2 variant and a meta-analysis

The clinical interpretation of variants in mismatch repair (MMR) genes associated with Lynch syndrome can be confusing when the functional nature of the variant is not clearly defined. We report an extreme case where a polymorphism in the MSH2 gene which had a low minor allele frequency, was misclassified as a mutation based on low evidential methods in the database and previous publications. We expanded this experience to perform a systematic meta-analysis in order to investigate other variants that have potentially been misclassified. Our results suggested that the interpretation of pathogenicity should be more cautious and emphasized the need for solid validation through multiple analyses including functional analysis for variants in MMR genes.     

卵巢上皮癌中ING4 基因启动子的甲基化状态及其临床意义

目的：探讨卵巢上皮癌中ING4 基因启动子的甲基化状态及其临床意义。方法：收集2005 年7 月至2012 年6 月哈尔滨医科 大学附属第一医院行全面分期手术并经病理检查确诊的150 例卵巢上皮癌组织标本,并以同期因子宫肌瘤或子宫腺肌症行子宫 全切除术或次全切除术并经病理检查确诊为正常卵巢组织的150 例标本作为对照组。采用甲基化特异性PCR（MSP）技术检测卵 巢上皮癌组织与正常卵巢组织中ING4 基因启动子的甲基化状态,蛋白印迹法检测ING4 蛋白的表达,并分析ING4 基因启动子 的甲基化状态与卵巢上皮癌临床病例特征的关系。结果：卵巢上皮癌组织中ING4 基因启动子的甲基化阳性率为42.7%（64/150）, 明显高于正常卵巢组织（4%,6/150）,差异有统计学意义（P<0.05）。ING4 基因启动子甲基化阳性的卵巢上皮癌组织中ING4蛋白 表达阴性或弱阳性;ING4 基因启动子甲基化阴性的卵巢上皮癌和正常卵巢组织中ING4 蛋白表达阳性;在64 例ING4 基因启动 子甲基化的卵巢上皮癌组织中,ING4 蛋白表达强度与ING4 基因启动子的甲基化程度呈负相关（r=-0.435,P<0.05）。卵巢上皮癌 组织中,ING4 基因甲基化的阳性率随着手术病理分期和组织学分级的增加而增加（P<0.05）;卵巢透明细胞癌（55.6%,10/18）和卵 巢子宫内膜样癌（59.3%,16/27）中ING4 基因甲基化的阳性率显著高于浆液性囊腺癌（33.9%,20/59）和粘液性囊腺癌（39.1%, 18/46）（P<0.05）;ING4基因启动子的甲基化状态与患者的年龄、有无腹水及淋巴结转移均无显著相关性（P>0.05）。结论：ING4 基 因启动子的甲基化可能促进了其在卵巢上皮癌组织中的表达失活,进而促进了卵巢上皮癌的生长和分化。     

全数字化X线摄影联合MR 动态增强检查诊断早期乳腺癌的 临床价值研究

摘要目的：分析早期乳腺癌的全数字X 线摄影与MRI影像学表现,评价全数字X 线摄影联合MRI 检查在早期乳腺癌诊断中的 临床价值。方法：回顾性分析2009 年10 月至2012 年5月在我院经穿刺或手术病理证实为早期乳腺癌的42例患者的临床资料, 术前均行数字X线及动态增强MR 检查,比较两种方法单独使用和联合使用的诊断乳腺癌的准确率。结果：全数字化X 线摄片 诊断早期乳腺癌的准确率为69.0%(29/42),动态增强MR 检查为95.2%(40/42),两者比较差异有统计学意义(P<0.05);两者联合使 用诊断早期乳腺癌的准确率为97.6%(41/42)。结论：动态增强MR 检查对早期乳腺癌的诊断价值明显优于全数字X线摄影,但后 者对微小钙化显示较好,两者联合可提高诊断正确率,尤其对多腺体型和致密型乳腺的早期乳腺癌的检出具有重要的价值。     

两株淡水微囊藻的藻蓝蛋白基因间隔序列(PC-IGS)分析

对2株编号为003和004的淡水水华微囊藻(Microcystis.sp)的藻蓝蛋白基因间隔序列进行测定,获得长度均为608bp的2条序列。同时从GenBank中获取铜绿微囊藻(Microcystis aeruginosa Kütz,NCBI序列号AJ003179)及惠氏微囊藻(Microcystis wesenbergii,NCBI序列号AF385391)的序列。分别运用MEGA3及ClustalX(Version1.83)软件对这4株藻的PC-IGS序列进行碱基组成分析和序列比对。碱基组成的比对结果表明4株藻的G+C含量分别为003(50.5%),004(51.7%),铜绿微囊藻(50.7%),惠氏微囊藻(52.3%),相差范围在0.2%~1.8%之间,其结果不足以区分这四株微囊藻;序列比对则表明003号藻株与铜绿微囊藻和惠氏微囊藻的序列相似性分别为100%和88.35%,而004号藻株与铜绿微囊藻和惠氏微囊藻的序列相似性比较结果为95.13%和89.04%。此外,文章还探讨了PC-IGS序列作为微囊藻种间鉴定分子标记的可行性。     

Leaf epidermal features of Rhododendron (Ericaceae)from China and their systematic significance

Rhododendron is the largest genus within the subfamily Rhododendroideae, which has about 1000 known species in the world and more than 500 species in China. Since the genus was established by Linnaeus, its infrageneric relationships have been well studied by many taxonomists on the basis of morphological characters and molecular data. In 1996, Chamberlain et al. proposed a new system of Rhododendron with eight subgenera, i.e., Azaleastrum, Candidastrum, Hymenanthes, Mumeazalea, Pentanthera, Rhododendron, Therorhodion, and Tsutsusi. In this paper, micromorphological characters of leaf epidermis in 4 varieties, 48 species, 6 subgenera of Rhododendron from China were examined using light microscopy (LM) and scanning electron microscopy (SEM). Leaf epidermal features are described and micromorphological types are distinguished here according to morphological characters such as scale, gland, foliar trichome and stomatal apparatus of leaf epidermis. It is shown that the leaf epidermal cells are usually irregular or polygonal in shape. The patterns of anticlinal walls are straight, arched or undulate. The stomatal apparatuses are anomocytic and are usually found on abaxial, not adaxial, epidermis. The results also show that: (1) the lepidote rhododendron (i.e., subgen. Rhododendron), which has both scales and papillae on leaf epidermis, differs distinctly from the elepidote rhododendron; (2) three types of leaf epidermis are identified in subgen. Hymenanthes (i.e., R. fortunei-type, R. chihsinianum-type and R. simiarum-type), whereas four in subgen. Tsutsusi (i.e., R. mariesii-type, R. simsii-type, R. mariae-type and R. flosculum-type); (3) except for R. westlandii and R. henryi, the species of subgen. Azaleastrum show similar morphological characters, i.e., dense stomatal apparatuses surrounded by ringed or discontinuous striates; (4) R. molle of subgen. Pentanthera differs from the species of other subgenera on morphological characters such as foliar trichomes, dense stomatal apparatuses with asymmetrical outer stomatal rims surrounded by undulate-striates, and no gland; (5) only R. redowskianum is found with distinct T-pieces at the polar region of guard cells in Rhododendron. The results support the conclusion inferred from molecular systematic studies that subgen. Therorhodion is the basal clade of Rhododendron. Finally, the relationships between the closely related species are also discussed on the basis of leaf epidermal features.     

茄科天仙子族的叶表皮特征及其系统学意义

在光学显微镜和扫描电镜下,观察了茄科天仙子族７属２１种及其邻近类群２属３种共２４种植物的叶表皮特征。结果表明：气孔器在各种植物的上、下表皮均有分布,多为无规则型,也有不等细胞型;叶表皮细胞形状有不同规则形、十字形、近长圆形和不规则多边形,垂周壁较平直、浅波状、波状或深波状。在扫描电镜下可见：叶表皮气孔器外拱盖内缘近平滑、浅波状或波状;角质膜多为具条纹,也有同时具条纹和颗粒或鳞片,偶尔仅具颗粒和鳞片     

侏罗纪中蜉属和珠蜉属蜉蝣昆虫化石研究的新进展

长期以来,我国昆虫化石研究者所确认,并为众多地层古生物工作者所引用,作为地层对比和确定地质时代的两种侏罗系蜉蝣幼虫化石:西伯利亚中蜉(MesobaetissibiricaBrauer,RedtenbacheretGanglbauer,1889)和古珠蜉(MesonetaantiquaBrauer,RedtenbacheretGanglbauer,1889)在我国境内并不存在。迄今为止,这两个种仅局限于俄罗斯西伯利亚下侏罗统。此前,被我国昆虫化石研究者分别归入中蜉属(MesobaetisBrauer,RedtenbacheretGanglbauer,1889)和珠蜉属(MesonetaBrauer,RedtenbacheretGanglbauer,1889)的所有种类,其科级和属级分类位置有误。它们包括:西伯利亚中蜉,三间房中蜉(MesobaetissanjianfangensisHong,LiangetHu,1995),黑斑中蜉(MesobaetismaculataHong,LiangetHu,1995),古珠蜉和北票珠蜉(MesonetabeipiaoensisWang,1980)。道虎沟组、海房沟组、九龙山组和三间房组的水生蜉蝣组合完全不同,彼此不能对比。我国侏罗系—下白垩统蜉蝣幼虫全部是湖相,为原地埋藏,而非河流相,异地埋藏类型。     

谈《伤寒论》中的欲愈候

欲愈候是预示疾病将愈的一类证候。文章列举《伤寒论》中6种典型欲愈候，并结合后世医家评述，分别探讨其临床指征、作解机理、现代临床意义，这对于临床把握疾病的发展规律以及指导临床用药等，均具有一定的积极意义。