CACO3 OPTICAL DETECTION WITH FLUORESCENT IN SITU HYBRIDIZATION: A NEW METHOD TO IDENTIFY AND QUANTIFY CALCIFYING MICROORGANISMS FROM THE OCEANS1

Open oceanic calcification is mainly driven by unicellular organisms and in particular by eukaryotes such as coccolithophores and foraminifers. Open ocean microcalcifiers, like most planktonic protists, are characterized by extremely fast generation times and occasional sexual reproduction. Populations can alternate between diploid and haploid stages, which often build different kinds of cell covers. In the most important pelagic calcifiers, the coccolithophores, the diploid and haploid stages, which can self‐replicate and grow independently, display radically different morphologies with different modes of calcification or even with the absence of calcification in at least one life cycle stage. Although life cycle strategies seem likely to fundamentally influence the where and when of open ocean calcification, this issue has yet to be seriously addressed in the natural environment. Here, we introduce a new morphogenetic method, “combined CaCO₃ optical detection with fluorescent in situ hybridization,” or COD‐FISH, which is based on a combination of TSA‐FISH and polarized optical microscopy. This technique allows simultaneous assessment of the taxonomic and life cycle status of single coccolithophore cells collected from the ocean. We demonstrate the application of COD‐FISH using both laboratory culture and field samples and discuss its potential value for assessing the ecology, biodiversity, population structure, and life cycles of coccolithophores and other open ocean unicellular calcifiers.     

PHYLOGENETIC UTILITY OF rbc S SEQUENCES: AN EXAMPLE FROM ANTITHAMNION AND RELATED GENERA (CERAMIACEAE, RHODOPHYTA)

We report the potential phylogenetic utility of the small RUBISCO subunit ( rbc  S) sequences from a sampling of Antithamnion and related genera in ceramiacean algae. The size of rbc  S was 417 bp for all taxa examined. Analyses of the DNA sequence data indicated that pairwise divergences of rbc  S sequences were 3.3%–9.8% among species of Antithamnion , and ranged from 13.6% to 18.0% between Antithamnion and related genera. Phylogenetic analyses fully resolved relationships at the intrageneric level with statistical significance supported by high bootstrap values. Two subgenera of Antithamnion , Pteroton and Antithamnion , were clearly distinguished in the molecular tree. In the clade of subgenus Pteroton , A. aglandum was allied with A. callocladum and separated from A. nipponicum. In the pairwise distance comparison of sequence variation, Ceramium showed the greatest genetic distances among genera examined in the study. All phylogenetic trees generated by the maximum parsimony, neighbor joining, and maximum likelihood were completely congruent in topology with high confidence.     

慢性肺心病肺动脉平滑肌细胞的胶原合成：体内及体外观察

肺动脉构形重建（ｓｔｒｕｃｔｒｕｒａｌｒｅｍｏｄｅｌｉｎｇ）是慢性肺心病的重要血管病变,但其发生机制至今未完全明了。病变以血管中膜平滑肌细胞肥大、增生和细胞外基质（包括纤维性与非纤维性成分）增多导致的血管壁增厚、血管腔狭窄为特征。本文用天狼星红－偏振光显微镜观察,真彩色全自动图像分析法,测量１０例慢性肺心病尸检肺小动脉中膜厚度及中膜内Ⅰ、Ⅲ两型胶原的含量和所占的百分比。用３Ｈ－胸腺嘧院核苷和３Ｈ－脯氨酸掺入法,观察缺氧内皮细胞条件培养液（ＨＥＣＣＭ）对培养的肺动脉平滑肌细胞（ＰＡＳＭＣＳ）ＤＮＡ及胶原合成的影响。结果：（１）肺心病组４３７支肌型肺动脉平均中膜厚占血管直径的百分值高于对照组５±１．０８％;（２）肺心病组的Ⅰ型和Ⅲ型胶原面积分别占中膜面积的５４．６２％和５１９％,而对照组两型胶原占中膜面积小于２％。（３）ＨＥＣＣＭ组平滑肌细胞的３Ｈ－ＴｄＲ和３Ｈ－脯氨酸掺入量（ｃｐｍ值）,均明显高于常氧对照组（ＮＥＣＣＭ）,两组相比,有显著性差异（Ｐ＜０．０１）。（４）细胞周期分析,ＨＥＣＣＭ组平滑肌细胞的Ｇ０／Ｇ１期细胞数百分值比ＮＥＣＣＭ组少２８％,Ｇ２＋Ｍ期细胞百分值则比ＮＥＣＣＭ组高３０％。可以认为,缺     

内蒙古眼蕈蚊五新种及—中国新记录属(双翅目:眼蕈蚊科)

眼蕈蚊科(Sciaridae)为双翅目中小型暗色的蚊类,触角16节,复眼向背面尖突形成眼桥。眼蕈蚊的种类多、数量大,幼虫多生活在富有腐植质的土壤中,常危害植物的地下部分及野生和栽培的菌蕈。我国的眼蕈蚊种类相当多,但内蒙古缺乏调查,本文就现有的标本记述了5新种,代表5个属,内有一中国新记录属。新种的模式标本保存在北京农业大学昆虫标本室。     

准噶尔盆地北缘谢家阶底界一推荐界线层型及其生物一年代地层和环境演变意义

新疆准噶尔盆地北缘铁尔斯哈巴合地层剖面构造简单并含有丰富的晚渐新世及早中新世哺乳动物化石.其中铁尔斯哈巴合组及索索泉组沉积基本连续,两组界线位于剖面米距33 m处.依据该剖面中8个层位和相邻的XJ99005剖面中18个层位上采集的化石以及它们的上下关系和生物组合性质,划分出5个哺乳动物组合带,其中两个位于铁尔斯哈巴合组中(铁-Ⅰ,Ⅱ带),3个在索索泉组下部(索-Ⅰ,Ⅱ,Ⅲ带).从剖面的铁尔斯哈巴合组、索索泉组和哈拉玛盖组中以0.5 m的间距采集了348组古地磁样品,获得的磁性剖面包含了16个正向带和16个反向带(事件),其中包含了相当于地磁极时间表中C7n～C5E段的完整磁极带.铁-Ⅰ～Ⅱ带与塔本布鲁克哺乳动物群相近,为中国已知位置最西、构成门类和数量最多的一个晚渐新世哺乳动物组合.索-Ⅰ带应为中国目前所知的最晚渐新世的哺乳动物带.早中新世索-Ⅱ带与谢家动物群和蒙古中部渐新世-中新世过渡带D带可以对比.早中新世索-Ⅲ带相当于过去使用的"索索泉动物群",时代大致与乌尔图动物群相当.根据地磁极时间校正,铁尔斯哈巴合剖面中铁尔斯哈巴合组和索索泉组跨越了从24.5 Ma(地磁极时带C7n.2n)到18 Ma(地磁极时带C5Dr.2r)大约6.5 Ma的时间,岩体平均沉积速率大约为2.5 cm/千年.剖面中5个生物组合带的时间跨度大致分别为:铁-Ⅰ带:24.4～24.15 Ma;铁-Ⅱ带:23.2～23.1 Ma;索-Ⅰ带接近但还未到达渐新世/中新世界线的23.03 Ma;索-Ⅱ带:21.9～21.7Ma;索-Ⅲ带:21.68～21.15 Ma.我们推荐将铁尔斯哈巴合剖面作为中国区域年代地层单位谢家阶(期)底界界线层型的一个候选剖面.与谢家阶底界相对应的界线暂定在剖面由底向上40.25 m处,对应于地磁极时带C6Cn.2n底界.该界线位于索索泉组内部,索-Ⅰ和索-Ⅱ带之间.根据定义,该界线也分别对应于阿基坦阶、中新统以及新近系的底界,年龄为23.03 Ma.文章还讨论了下列问题:1)索索泉组的绝大部分应当和谢家阶以及山旺阶地层对比,仅其底部含有索-Ⅰ带化石组合的部分可与塔本布鲁克阶地层对比.2)在进行生物地层对比时尽量使用不同的索索泉组哺乳动物组合带,传统的"索索泉动物群"仅大体相当于索-Ⅲ带.3)许多过去认为的渐新世哺乳动物分子的生存时代实际上延伸到了早中新世,仅以这些分子的存在,不能说明一个动物群及其地层的确切年代.4)塔本布鲁克动物群及相关的期、阶名为有效名称,具有合法性;该阶底界有待确立.5)如果山旺阶底界(谢家阶顶界)位于地磁极时带C6An.1r底,年代为20.43 Ma,相应的界线应位于铁尔斯哈巴合剖面89.25 m处,因此,铁尔斯哈巴合剖面中有可能产生谢家阶的单位层型,该阶的地质时间跨度为2.6 Ma.6)5个生物带都是以兔形类、啮齿类以及食虫类等小哺乳动物为主要分子,而且同门类的属种间具有相当近的演化关系,说明这个地区从晚渐新世到早中新世的一段时期中,动物群性质没有明显变化,总体上反映了一个从早渐新世以来就比较干旱的环境;渐新世和中新世动物群成分在种一级上仍有明显差异;而相当于谢家动物群的索-Ⅱ带则带有明显的过渡性质.7)从索索泉组的岩性、分布的地理部位以及与甘肃秦安剖面相近的时代和动物群等来看,不排除含有风成沉积物的可能.