Rana johnsi的生物学初探

从保护生物学角度对广西大瑶山Rana johnsi Smith,1921的的栖息地和繁殖地生境、 繁殖生物学及蝌蚪的特点等进行了初步探讨。该蛙在大瑶山主要分布在海拔800m左右的一个狭窄区域,10月至次年1月下山繁殖,有效性比为5：1。蝌蚪唇齿式为Ⅰ：5—5／1—1：Ⅳ和Ⅰ：4—4／1—1：Ⅳ,越冬后在5～6月完成变态。由于人为和自然因素的影响,该蛙种群受到严重威胁,应加强保护管理和宣传教育。     

冬眠对达乌尔黄鼠盲肠菌群的影响

冬眠哺乳动物的肠道微生物会发生季节性变化,同时在冬眠期间动物处于禁食状态,对肠道微生物的多样性和组成也产生影响。本研究通过16S rRNA基因高通量测序分析达乌尔黄鼠育肥阶段 (起始育肥期、快速育肥期、育肥完成期) 和冬眠阶段 (冬眠早期、冬眠晚期、出眠期) 共6个时期盲肠菌群的多样性、组成和功能,并通过冗余分析 (RDA) 探究其生理特征与菌群组成和功能之间的关系,揭示达乌尔黄鼠盲肠菌群的季节性变化。菌群组成的分析显示达乌尔黄鼠盲肠菌群主要由厚壁菌门 (Firmicutes)、拟杆菌门 (Bacteroidetes) 和疣微菌门 (Verrucomicrobia) 组成。与其他时期相比,冬眠早期厚壁菌门的相对丰度减少,拟杆菌门和疣微菌门的相对丰度增加。在Alpha多样性中,起始育肥期、快速育肥期和冬眠早期的Chao1和ACE指数显著低于出眠期,育肥完成期的Simpson指数显著低于快速育肥期 (P < 0.05) 。通过加权和非加权的UniFrac距离矩阵的主坐标分析发现盲肠菌群均显示出了明显的季节性聚类。PICRUSt分析中,丁酸代谢等代谢通路在育肥阶段富集,冬眠阶段集中在氮代谢等相关通路中。RDA分析显示达乌尔黄鼠不同时期的生理特征与其盲肠菌群的组成和功能显著相关。本研究表明,冬眠使达乌尔黄鼠盲肠菌群的多样性和相对丰度发生改变,盲肠菌群组成和功能的变化调节了达乌尔黄鼠的生理代谢,使达乌尔黄鼠适应季节性的环境变化。     

Pseudointegricorpus clarireticulatum (Samoilovitch) Takahashi: morphology and ultrastructure

Dispersed tricolpate pollen of Pseudointegricorpus clarireticulatum (Samoil.) Takah. from the Upper Maastrichtian in Zeya-Bureya Basin, Amur (Heilongjiang) River area, Russian Far East/China has been studied with light and electron microscopy. Pollen size, pole outlines and the shape of equatorial projections show some variation within the species. The exine is striate-reticulate, semitectate and columellate. The species is characterised by highly complex structures that have harmomegathic function and include equatorial projections, endexinous thickenings, difference in the thickness of the infratectum, foot layer and endexine throughout the pollen grain, and equatorial furrows. Exine layers taper towards colpi regions while they break abruptly in furrow regions. The furrows could have helped to shed the exine quickly and enabled pollen germination. A non-extended region with a small cavity in the ectexine was observed in the equatorial region. We think that this region is characteristic of most Triprojectate species.     

森林多目标经营单元的时空尺度扩展

森林多目标经营是我国林业发展的重要趋势,而森林本身的特性以及国内外的众多研究证明,森林多目标经营需要考虑多个时空尺度,以满足其生态、经济和社会效益的综合发挥。在界定多功能林业和森林多目标经营的概念及基础上,系统地分析了传统森林经营时空尺度和现代森林多目标经营时空尺度的联系与区别,提出现代森林多目标经营单元空间尺度上应该满足区域、景观和林分多尺度的需要,而在时间尺度上则要综合考虑短期、中期和长期,并以露水河林业局为例给出具体的研究思路,以期为我国开展森林多目标经营提供借鉴。     

PKD1 is downregulated in non-small cell lung cancer and mediates the feedback inhibition of mTORC1-S6K1 axis in response to phorbol ester

Protein kinase D1 (PKD1) is increasingly implicated in multiple biological and molecular events that regulate the proliferation or invasiveness in several cancers. However, little is known about the expression and functions of PKD1 in non-small cell lung cancer (NSCLC). In the present study, 34 pairs of human NSCLC and matched normal bronchiolar epitheliums were enrolled and evaluated for PKD1 expression by quantitative real-time PCR. We showed that PKD1 was downregulated in 26 of 34 cancer tissues in comparison with matched normal epitheliums. Moreover, patients with venous invasion or lymph node metastasis showed significant lower expression of PKD1. Exposure of NSCLC A549 and H520 cells to the PKD family inhibitor kb NB 142-70(Kb), at concentrations that inhibited PKD1 activation, strikingly potentiated S6K1 phosphorylation at Thr³⁸⁹ and S6 phosphorylation at Ser^235/236 in response to phorbol ester (PMA). Knockdown of PKD1 with siRNAs strikingly enhanced S6K1 phosphorylation whereas constitutively active PKD1 resulted in the S6K1 activity inhibition. Furthermore, the PI3K inhibitors LY294002, BKM120 and MEK inhibitors U0126, PD0325901 blocked the enhanced S6K1 activity induced by Kb. Collectively, our results identify decreased expression of the PKD1 as a marker for NSCLC and the loss of PKD1 expression increases the malignant potential of NSCLC cells. This may be due to the function of PKD1 as a negative regulator of mTORC1-S6K1. Our results suggest that re-expression or activation of PKD1 might serve as a potential therapeutic target for NSCLC treatment.     

Immobilizing bifenthrin on wood for termite control

Termites are world-wide pests causing significant losses to annual and perennial crops, as well as damages to wooden components in buildings. Although various chemical, physical, and biological methods have been explored to prevent termite attack on wooden structures, new guiding principles are still needed for environmental protection. In this study, by combining the effective chemical control of bifenthrin and photo-immobilization technique of biomolecules, we developed chitosan as a carrier to embed bifenthrin, which was then immobilized by ultraviolet treatment on the surface of wood (Cunninghamia lanceolata). The immobilized bifenthrin embedded in the photoactive chitosan was characterized by Fourier transform infrared spectroscopy (FTIR), C.H.N analysis, ultraviolet, and fluorescence measurements. The surface structures and biological activity were examined by scanning electron microscopy (SEM), atomic force microscope (AFM), electron spectroscopy for chemical analysis (ESCA), and bioassays. The results indicated that the immobilized bifenthrin can be well protected from free and non-controlled releasing, and has a long-term stability allowing high efficiency against the termite at a dose of 2.5 ??g/cm². This study provides a novel and environmentally-benign technique for the termite control by photo-immobilizing the bifenthrin-embedded chitosan on the surface of C. lanceolata. This technique may be used in combination with the traditional methods for effective termite control.     

中国小头蛇属(蛇亚目,游蛇科)的分类修订

基于40号标本的形态研究,对中国小头蛇属Oligodon进行分类修订。四线小头蛇Oligodon taeniatus(Güther,1861)在中国没有分布,当初发表该纪录所依据的3号标本为紫棕小头蛇指名亚种Oligodon cinereus cinereus(Güther,1864);中国记录的管状小头蛇Oligodon cyclurus(Cantor,1839)应订正为束纹小头蛇Oligodon fascioatus(Güther,1864)。根据色斑、鳞被和半阴茎等综合特征,提出中国记录的喜山小头蛇Oligodon albocinctus包括2个物种,其中云南省陇川县标本为喜山小头蛇Oligodon albcinctus(Cantor,1839),而西藏墨脱县标本是尚未明确的小头蛇属未定种Oligodonsp.,其分类地位有待进一步研究。最后,提供中国分布的小头蛇属物种检索表。     

瘦蛋白对摄食和能量平衡的调节及其在哺乳动物冬眠中的作用

白色脂肪合成和分泌的瘦蛋白(leptin)作用于下丘脑和外周的代谢产热器官,对摄食和能量平衡起调节作用。摄食和能量平衡的失调,如瘦蛋白抵抗,可以导致肥胖等一系列生理疾病。以体内贮存的脂肪为主要能源物质越冬的冬眠哺乳动物,体重的年周期波动幅度巨大,其摄食和能量平衡调节机制可能不同于一般的非冬眠物种,育肥阶段可能存在瘦蛋白抵抗机制。本文总结了瘦蛋白调节摄食和能量平衡的作用机制以及瘦蛋白对冬眠哺乳动物育肥和冬眠的影响,为进一步研究冬眠哺乳动物的能量平衡提供参考。     

基于ISSR标记的辽宁4个东北林蛙种群遗传多样性分析

辽宁是东北林蛙Rana dybowskii主要分布地之一,种群数量巨大,其群体遗传多样性有待评估.本研究应用ISSR标记技术对东北林蛙4个种群105个样本进行研究,5个引物共获得44条清晰谱带,4个种群的多态位点率均大于75%,Nei's基因多样性为0.2851,Shannon信息指数为0.4476,显示了较高的遗传多样性.对遗传分化系数、Nei's遗传距离、AMOVA分子变异巢式方差分析和F-统计量等遗传参数的统计结果表明,辽宁东北林蛙种群间已经出现一定程度的遗传分化,分析认为,自然屏障(高山和平原等)以及栖息地片段化是其遗传分化形成的主要因素.     

基于遥感分析的锦州湾海域填海造地变化

利用Landsat TM和高精度ALOS影像数据,在比较不同水体指数提取海域面积精度的基础上,利用改进的归一化差异水体指数(MNDWI),研究了1988、1995和2006年锦州湾海域填海造地情况.结果表明:1988-2006年间,锦州湾海域填海造地面积达23.63 km2,其中,12.38 km2被用作开发区建设,5.48 km2用于工业用地,3.47 km2用于码头建设,1.37 km2被用作养殖用地,0.93 km2被用为滨海浴场.大面积填海造地反映了锦州湾沿海城市建设和经济发展对土地的强烈需求,同时也必然会对该区域的生态环境造成较大影响,需要进一步加强监测和评价.