22种木莲属植物亲缘关系的SRAP分析(英文)

利用SRAP标记分析技术探讨了22种木莲属植物的遗传亲缘关系。选用13对SRAP引物组合对木莲属22个种的基因组进行分析。结果表明:22个种共扩增出981条DNA带,其中多态性条带占94.8%;在Nei’s遗传相似性系数0.70处,UPGMA聚类将22个种分为5个类群,在0.715分为9个亚类;22种木莲属植物的Nei’s遗传相似性系数变化范围为0.625(乳源木莲与球果木莲之间)～0.914(中缅木莲与滇南木莲之间),平均遗传相似性系数为0.696。其中中缅木莲、滇南木莲之间遗传相似性系数为0.914,两者亲缘关系最近。该结果支持将巴东木莲、乳源木莲、滇桂木莲分别作为独立的种。     

海南木莲叶挥发油化学成分研究

目的：分析海南木莲叶的挥发油成分。方法：采用水蒸气法提取挥发油,气相色谱-质谱-计算机联用技术分析。结果：共鉴定出49种化合物,占挥发油总量的99．99％,其中主要成分是橙花叔醇（16．44％）;3,7-二甲基-2,6-辛二烯-1-醇（5.27％）;3,7-二甲基1,6-辛二烯-3-醇（5．12％）;α-丁香烯（4．97％）和丁香烯（4．48％）。     

濒危植物大果木莲种群格局及濒危原因分析

采用径级结构代替年龄结构以及方差均值比率法对木兰科(Magnoliaceae)木莲属(Manglietia Bl.)濒危植物大果木莲(Manglietia grandis Hu et Cheng)种群的年龄结构和种群格局进行了研究,并编制了大果木莲种群的特定时间生命表和存活曲线;结合生殖生物学特征以及遗传多样性研究结果,分析了导致大果木莲濒危的主要原因.根据株高和胸径可分别将大果木莲种群的年龄结构分为5级、高度结构分为6级;在大果木莲的5个年龄结构分级中,成年个体较多,幼年个体较少;其高度结构完整,个体高度主要在20 m以下.种群的方差均值比率为0.838 3,其空间分布格局属于随机分布.根据特定时间生命表可将大果木莲种群的发育分为3个阶段:幼树阶段(年龄级为Ⅱ～Ⅲ级)、成树阶段(年龄级为Ⅲ～Ⅳ级)、老树阶段(年龄级为Ⅳ～Ⅴ级),其中成树阶段个体死亡率最低.大果木莲种群存活曲线接近Deevey Ⅰ型,属于衰退型种群.种群自我更新能力差、种子生产力低下、有性生殖困难、生境片断化导致的基因流受限以及人为干扰是大果木莲濒危的主要原因.针对大果木莲濒危现状和致危原因,提出了相应的保护对策和建议.     

Glycodelin protein and mRNA is downregulated in human first trimester abortion and partially upregulated in mole pregnancy.

Glycodelin (Gd) is a major reproductive glycoprotein and a mediator for immunomodulatory effects directed to cellular, humoral, and innate immunity. Human pregnancy depends on a diversity of physiological processes including modulation of the maternal immunosystem. We evaluated the expression of Gd protein and mRNA in first trimester decidual tissue of normal pregnancies and spontaneous abortion and hydatidiform moles. Furthermore, in vitro experiments on endometrial cancer cells to analyze the effect of human chorionic gonadotropin (hCG) on Gd regulation were performed. In decidual tissue of abortion patients, Gd expression was significantly decreased compared with normal gestation, which was confirmed by in situ hybridization. In mole pregnancy, an upregulation of Gd in the first 8 weeks of pregnancy was present. Gd is a main product of decidual tissue in the first trimester of human pregnancy. Reduced Gd expression in abortive pregnancy could lead to an increased activation of the maternal immunosystem, thus causing rejection of the developing fetus. Moreover, Gd expression in endometrial cancer cells in vitro could be stimulated by addition of hCG. Therefore, we speculate that hCG could be one of the factors regulating Gd expression because hCG is downregulated in women with abortion and upregulated in mole pregnancy. In addition, we found a positive feedback loop in Gd and hCG expression in human pregnancy.     

濒危植物巴东木莲的分布及保护策略

为了研究中国特有物种国家二级保护植物巴东木莲(Manglietiapatungensis)的濒危机制,对巴东木莲的分布现状、生境进行了野外调查。原生巴东木莲的空间分布范围是北纬28°47′10″～30°51′53″,东经107°9′～110°38′9″;垂直分布为海拔374～1029m。湖北咸丰县尖山乡和湖南桑植五道水乡杨家坪村为巴东木莲的新分布点。从整体来看,巴东木莲的分布是不连续的、零星的,而且范围很狭窄;分布区的环境条件差异大。人类对巴东木莲的不合理利用及生境片断化是造成其野生资源迅速减少和许多现有种群不能自然更新的主要原因。还对巴东木莲的分布现状提出了相关的保护措施。只有采取保护优先、合理开发的措施,才可获得资源的可持续性利用。     

香木莲有性生殖特性与其濒危机制的研究

针对香木莲（Manglietia aromatica Dandy)结籽率低以及野外实生苗稀少的现象。本文研究了香木莲雌配子体发育过程,花粉萌发力,开花生物学特性与种子结构的观察。结果表明,在雌配子体发育阶段存在以下退化现象：1）从大孢子母细胞开始减数分裂到功能大孢子形成阶段,在此过程中珠心内的功能结构发生退化,功能大孢子未能正常形成,仅残留有退化痕迹,退化率为27．9％;2）胚囊成熟时,受精前卵器细胞发生退化,退化率为80％,花粉萌发实验结果表明,在人工培养条件下具有正常萌发能力的花粉不足0．01％,这些都是香木莲结籽率低的重要原因,同时,香木莲的开花生物学特性限制了传粉的顺利进行。调查和研究的结果显示,人为的砍伐是造成香木莲种群急剧减少的直接原因;有性生殖障碍和生境破坏是制约香木莲种群更近的最主要因素,由此提出了对香木莲的拯救和保护对策,就地保护;研究并推广繁育技术,进行种群重建;进行迁地保护,保存尽可能多的种质资源。     

Spatial analysis of structural and tree‐ring related parameters in a timberline forest in the Italian Alps

Abstract. We investigated the variability in spatial pattern of some structural, dendrochronological and dendroclimatological features of a mixed Larix decidua‐Pinus cembra forest at the timberline in the eastern Italian Alps at fine geographical and temporal scales. Forest structure variables such as stem diameter, tree height, age and tree‐ring related parameters (yearly growth index, mean sensitivity, first order autocorrelation and some dendroclimatic variables) have been compared at various scale levels. We observed that most of the variables show positive autocorrelated structures due to both forest dynamics and fine‐scale driving forces, probably related to microrelief. Spatial structure of yearly indexed radial growth appears sensitive to extreme climatic events. Secondary succession after past disturbances drives the forest towards a structure governed by a gap regeneration dynamics that seems to ensure the different requirements of the two main tree species present. Small spatial scale studies of forest structures, especially if integrated to dendro‐ecological data, seem an efficient tool to assess the disturbance regime and species sensitivity to environmental change.     

Conquering the cytokine storm in COVID-19-induced ARDS using placenta-derived decidua stromal cells

Acute respiratory distress syndrome (ARDS) is the most common cause of death in COVID-19 patients. The cytokine storm is the main driver of the severity and magnitude of ARDS. Placenta-derived decidua stromal cells (DSCs) have a stronger immunosuppressive effect than other sources of mesenchymal stromal cells. Safety and efficacy study included 10 patients with a median age of 50 (range 14–68) years with COVID-19-induced ARDS. DSCs were administered 1–2 times at a dose of 1 × 10⁶/kg. End points were safety and efficacy by survival, oxygenation and effects on levels of cytokines. Oxygenation levels increased from a median of 80.5% (range 69–88) to 95% (range 78–99) (p = 0.012), and pulmonary infiltrates disappeared in all patients. Levels of IL-6 decreased from a median of 69.3 (range 35.0–253.4) to 11 (range 4.0–38.3) pg/ml (p = 0.018), and CRP decreased from 69 (range 5–169) to 6 (range 2–31) mg/ml (p = 0.028). Two patients died, one of a myocardial infarction and the other of multiple organ failure, diagnosed before the DSC therapy. The other patients recovered and left the intensive care unit (ICU) within a median of 6 (range 3–12) days. DSC therapy is safe and capable of improving oxygenation, decreasing inflammatory cytokine level and clearing pulmonary infiltrates in patients with COVID-19.     

红花木莲有性繁殖和生态生物学特性的研究

红花木莲是木莲属中较原始的种类,是我国珍贵的用材及观赏树种,被列为国家保护植物。由于它自然更新能力差,加上人为的破坏,成年植株逐渐减少,已陷人濒危的境地。本文探索了其种子生理及萌发特性,掌握了有性繁殖中的关键技术措施,并通过引种栽培观测其生态生物学特性,认为在昆明引种栽培区内具有较强的适应性。提出了在扩大迁地保护的同时,将其一部分苗木返回自然生境中,进行种群重建,以扩大其种群,对保护和持续利用这一珍贵树种具有深远意义．     

Expression of mRNA encoding insulin‐like growth factors I and II by uterine tissues and placenta during pregnancy in the rat

The uterus and the placenta synthesize insulin‐like growth factors (IGFs) and insulin‐like binding proteins (IGFBPs). These growth factors are implicated in processes of proliferation and differentiation that occur in the uterus. To determine the patterns of expression of IGFs during rat pregnancy we used in situ hybridization with digoxigenin labeled probes on uterus from day 7 to day 16 of pregnancy. In early gestation days (7–8) both IGF mRNAs showed similar tissue distribution with relative abundance in the stroma and circular muscle layer. On days 11 and 12 expression for IGF‐I mRNA was found in the mesometrial decidua and metrial gland and in the ectoplacental cone while clear expression of IGF‐II mRNA could only be found in the latter. On days 13 and 14, expression for IGF‐I mRNA could be detected in the mesometrial decidua and metrial gland but no expression was observed for IGF‐II mRNA. A gradient of IGF‐I mRNA expression could be observed in the placenta on day 16, with the trophoblastic cells of the basal zone expressing the signal with stronger intensity than in the labyrinthine zone. For IGF‐II mRNA the highest expression was associated with the labyrinthine zone. Endovascular trophoblast was positive for both mRNAs. The spatial and temporal patterns of expression suggests a role for IGFs in the process of decidualization as well as in the establishment, growth and differentiation of the various trophoblast cells of the placenta. Mol. Reprod. Dev. 53:294–305, 1999. © 1999 Wiley‐Liss, Inc.