秦岭地区15kaBP以来的植被与环境

通过对秦岭海拔2200m-山间盆地沼泽沉积剖面的花粉分析和^14C年代测定,结合对该区植被与表土花粉的研究,认为秦岭的暗针叶林带15ka BP以来植被和环境经历了4个发展阶段：(1)约15450～6760a BP,植被为冷杉(Abies)-云杉(Picea)林,气候寒冷潮湿;(2)约6760～2940a BP,沉积物中花粉稀少,以冷杉、云杉、桦(Betula)、栎(Quercus)为主,出现了喜暖型植物桤木(alnus),气候暖湿;(3)2940～40a BP,植被为冷杉林,气候冷湿;(4)0～40a BP,植被为桦、栎、榛(Corylus)、桤木、铁杉(Tsuga)和小片状分布的冷杉,松(Pinus)的数量极少,气候向暖干方向发展,这是近期人为活动干扰的结果。     

最近12000年来青藏高原植被的时空分布

青藏高原 30个点湖泊的孢粉记录综合研究显示 :在进入全新世之前 (12kaBP以前 ) ,除最东南部外 ,高原从东到西均发育为荒漠草原植被。全新世早期 (12 .0 - 9.0kaBP)高原东南部 (10 4° - 98°E)为落叶阔叶林 /针阔叶混交林 ;中部 (98° - 92°E)为草甸或灌丛草甸 ,再向西至 80°E左右为草原植被 ;全新世中期 (9.0 - 3 .2kaBP)高原由东向西古植被依次发育为针阔混交林和硬叶阔叶林 (10 4° - 98°E)→针阔混交林 (98° - 94°E)→灌丛草甸 (94° -92°E)→草原 (92°- 80°E) ;全新世晚期 (3.2kaBP以后 )由东向西古植被依次为硬叶阔叶林→针阔混交林→草甸→草原→荒漠。     

最近12 000年来青藏高原植被的时空分布

青藏高原30个点湖泊的孢粉记录综合研究显示: 在进入全新世之前(12 ka BP以前),除最东南部外,高原从东到西均发育为荒漠草原植被.全新世早期(12.0-9.0 ka BP)高原东南部(104°-98° E)为落叶阔叶林/针阔叶混交林; 中部(98°-92° E)为草甸或灌丛草甸,再向西至80° E左右为草原植被; 全新世中期(9.0-3.2 ka BP)高原由东向西古植被依次发育为针阔混交林和硬叶阔叶林(104°-98° E)→针阔混交林(98°-94° E)→灌丛草甸(94°-92° E)→草原(92°-80° E);全新世晚期(3.2 ka BP以后)由东向西古植被依次为硬叶阔叶林→针阔混交林→草甸→草原→荒漠.     

法氏囊活性五肽BP5的抗肿瘤作用

【目的】法氏囊活性五肽Bursopentin(BP5)是一种多功能生物学活性因子,不仅具有免疫调节和抗氧化功能,还具有抗肿瘤活性。目前,BP5发挥抗肿瘤生物功能的作用机制尚不清晰。【方法】本研究利用T7噬菌体展示技术构建鸡DT40细胞T7噬菌体c DNA文库,以BP5-BSA为靶分子对文库进行亲和淘选,通过序列测定和生物信息学分析,获得BP5的结合蛋白。通过分析BP5诱导的鸡DT40细胞mRNA基因表达谱和检测BP5对HCT116细胞中p53 Luciferase活性和p53信号通路中相关蛋白表达的影响来探讨BP5抗肿瘤的作用机制。【结果】构建的鸡DT40细胞T7噬菌体c DNA文库原始滴度为1.2×104pfu/m L,重组率为91.7%,扩增后滴度为1.9×109pfu/m L;通过生物淘选获得3条与BP5结合的鸡源蛋白血管内皮生长因子A(vascular endothelial growth factor A)、细胞周期蛋白E1(cyclin E1)和运输蛋白颗粒复合体2(trafficking protein particle complex 2)。基因表达谱分析结果显示,BP5参与调节多条与抗肿瘤功能有关的通路,其中包括p53信号通路,且p53信号通路涉及的5个差异表达基因均与细胞周期调控或抗肿瘤相关,其中SIAH1、TP53(p53)、CIP1(p21)基因被上调,CHEK2、CCNE1基因被下调。RT-PCR方法检测10个表达水平有明显变化的差异基因,其结果与基因芯片分析结果相符;BP5对p53 Luciferase活性的影响实验结果显示,BP5在0.2-20μg/m L浓度下能够明显提高HCT116细胞中p53相对Luciferase活性,Western blotting结果证实,BP5能显著促进p53、p21蛋白的表达水平,而CCNE1和CHEK2蛋白的表达水平则明显降低。【结论】本研究结果表明BP5通过p53信号通路途径发挥其抗肿瘤生物学功能,为进一步研究BP5抗肿瘤具体的分子机制提供了参考依据。     

The Palaeovegetation Record of Monsoon Evolution in the Desert-loess Transition Zone for the Last 13 ka BP

The study was to clarify the events of monsoon climate recorded by the palaeovegetation, using the results of pollen analysis, organic carbon δ13C, together with high-resolution 14C dating in the desert-loess transition zone for the last 13 ka BP. The palaeovegetation went though in the order of 9 periods viz.:desert-grassland,steppe,semi-desert,humid-grassland,desert,sparse-wood-grassland, desert-grassland, grassland, and desert grassland. The semi-desert, humid-grassland, and desert corresponded with the Younger Dryas events of cold-dry, cool-humid, and cold-dry climate after the end of the last glaciation. The optimum of the Holocene and other humid period between 4.5-3.5 ka BP were of high significance in research area.     

沙漠／黄土过渡带13 Ka BP以来季风演化的古植被记录

利用花粉分析结果并结合有机碳δ＾１３Ｃ及高精度＾１４Ｃ测年等资料,阐明沙漠／黄土过渡区１３ｋａ ＢＰ以来古植被记录的季风气候事件。古植被经历了荒漠草原－干草原－半荒漠－湿润草原－荒漠－疏林草原－荒漠草原－草原－荒漠草原９个阶段。冰后期的半荒漠－湿润草原－荒漠对应于其中冷干－凉湿－冷干的Ｙｏｕｎｇｅｒ Ｄｒｙａｓ事件,全新世气候适宜期以及４．５－３．５ｋａ ＢＰ的另一气候料适宜期等在研究区均有明显表     

Changes in the vegetation and human management of forest resources in mountain ecosystems at the beginning of MIS 1 (14.7–8 ka cal BP) in Balma Guilanyà (Southeastern Pre-Pyrenees,Spain)

The site of Balma Guilanyà (southeastern Spain) records an extensive human occupation during the beginning of MIS 1, based on a variety of archaeobotanical indicators, although its sequence contains gaps in the record of human occupation. The study of different archaeological proxies recovered from its sequence, especially charcoal, seeds and fruits, allows analysis of the ecological changes that occurred at the southern flanks of the Pyrenees from the Bølling/Allerød amelioration to the Boreal. The analyses also illuminate the strategies developed by hunter-gatherers of the northeastern Iberian Peninsula, and especially of the changes in firewood used at this site over a long time (over 5000 years), which indirectly provide information about the transformation of the plant communities of mountain ecosystems. In parallel, a growing interest in re-collecting wild fruits can be perceived. The results suggest that this activity was widely in use during the early Holocene, although it may go back to the Allerød. These results suggest that despite the limitations of the archaeobotanical record of Balma Guilanyà, we can recognize different patterns in the management of plant resources by the hunter-gatherers that intermittently visited this site.     

Autoreactive T and B cells from bullous pemphigoid (BP) patients recognize epitopes clustered in distinct regions of BP180 and BP230

Bullous pemphigoid (BP) is a well-characterized model of autoantibody-mediated autoimmunity, which presumably depends on autoreactive Th cells that promote the activation of autoreactive B cells. The two major autoantigens of BP are BP180 and BP230, two components of dermoepidermal adhesion complexes. Both, autoreactive Th cell responses and autoantibody profiles were characterized in 35 patients with acute onset BP using BP180 and BP230 proteins. Our findings indicate the following: 1) autoreactive Th cells recognized epitopes within the NH2-terminal (77.1%), COOH-terminal (65.7%), and central portion (57.1%) of the BP180 ectodomain; 2) IgG autoantibodies were found to exhibit similar or identical reactivity against the NH2-terminal (82.8%), COOH-terminal (77.1%), and central portion (37.1%) of the BP180 ectodomain; 3) T and B cell reactivity with the NH2-terminal portion of the BP180 ectodomain was associated with extensive BP, whereas the central portion was more frequently recognized in limited BP; 4) only 7 of 16 (43.7%) and 6 of 16 (37.5%) BP patients showed a Th cellular response against the COOH- and NH2-terminal regions of BP230, respectively, whereas 5) IgG reactivity against the COOH- and NH2-termini of BP230 was detected in 5 of 16 (31.3%) and 6 of 16 (37.5%) patients, respectively. These results demonstrate that Th and B cell reactivities against BP180, are, in contrast to BP230 reactivity, almost constantly detectable in BP patients, and differential epitope recognition of BP180 seems to be associated with distinct clinical severity. These observations support the concept that BP180, but not BP230, is the primary autoantigen of BP critical for disease development.     

13C discrimination by fossil leaves during the late-glacial climate oscillation 12-10 ka BP: measurements and physiological controls

The late-glacial climatic oscillation, 12-10 ka BP, is characterised in ice core oxygen isotope profiles by a rapid and abrupt return to glacial climate. Recent work has shown that associated with this cooling was a drop in atmospheric CO₂ concentration of ca. 50 ppm. In this paper, the impact of these environmental changes on ¹³C discrimination is reported, based on measurements made on a continuous sequence of fossil Salix herbacea leaves from a single site. The plant responses were interpreted using an integrated model of stomatal conductance, CO₂ assimilation and intercellular CO₂ concentration, influenced by external environmental factors. According to the model, temperature exerts a marked influence on ¹³C discrimination by leaves and the pattern of ¹³C changes recorded by the fossil leaves is consistent with other palaeotemperature curves for 12-10 ka BP, particularly the deuterium isotope record from Alaskan Salix woods, which generally reflects ocean temperatures. The gas exchange model correctly accounts for these changes and so permits the reconstruction of ancient rates of leaf CO₂ uptake and loss of water vapour in response to the abrupt late-glacial changes in global climate and CO₂. The approach provides the required physiological underpinning for extracting quantitative estimates of past temperatures and for contributing an ecophysiological explanation for changes in ¹³C discrimination in the fossil record.     

Beitrag zur Kenntnis desStellario-Alnetum glutinosae (Mikyška 1944)Lohmeyer 1957 in der Tschechischen Sozialistischen Republik (ČSR)

DasStellario-Alnetum glutinosae aus Böhmen und Mähren wird in phytozönologischer Hinsicht behandelt. Diese Gesellschaft ist ein periodisch oder episodisch überschwemmter Erlen-Eschen-Auenwald der kollinen Stufe und der niedrigsten Lagen der submontanen Stufe. Nach der Bodenfeuchtigkeit und dem Bodenluftregime wurden die folgenden Subassoziationen unterschieden: 1. dasStellario-Alnetum crepidetosum mit langfristig versumpftem Oberboden und ungünstigem Luftregime des Bodens, 2. dasS.-A. chrysosplenietosum mit nassem bis feuchtem, jedoch nicht versumpftem Oberboden und relativ günstigem Bodenluftregime, 3. dasS.-A. allietosum ursini mit feuchtem bis frischem Oberboden und günstigem Bodenluftregime und 4. dasS.-A. typicum mit feuchtem bis etwas austrocknendem Oberboden und sehr günstigem Bodenluftregime.     

四万年来南海北部周边地区植被演替序列—孢粉生物群区化方法恢复古植被的尝试

就南海北部海域17940孔的孢粉资料,利用孢粉生物群区化方法和因子分析方法,对南海北部周边地区4万年以来的植被演替序列进行研究。结果表明：对于深海沉积物,在排除远距离搬运的花粉尤其是松属（Pinus L.)花粉的噪音后,可以利用孢粉生物群区化方法恢复周边大陆古植被演替序列。因子分析表明,湿度和温度的变化是影响南海北部周边大陆植被演化的主要因子。在40500－11100aBP南海北部沿海大陆地区的古植被,主要为常绿阔叶林（WAMF）,山地针叶林（MRGF）分布于低山、丘陵、而广泛出露的大陆架上则发育了以蒿属(Artemisia L.)为主的草原（STEP）景观：末次冰期时环境变化的突出特征山地针叶林（MRGF）、常绿阔叶林（WAMF）与草原（STEP）之间的频繁交替,反映了气候冷湿和温干的千年级尺度的迅速变化,可以与Heinrich事件以及Dansggard-Oscherge事件进行对比。其中在7.0m处（12700aBP)所恢复的山地针叶林（MRGF）景观反映了一次气候变冷变湿的事件,可能与新仙女木事件相对应。全新世早期和末期较多出现热带雨林（TRFO0以及热带季雨林（TSFO）景观,而全新世中期以常绿阔叶林（WAMF）为主,缺乏热带雨林（TRFO）以及热带季雨林（TSFO）景观,可能表明在全新世中期尽管温度升高,但湿度有可能降低。     

Increasing the resolution of the Broad Spectrum Revolution in the Southern Levantine Epipaleolithic (19-12 ka)

We analyze terminal Pleistocene archaeofaunal diversity trends in the Southern Levant by examining eight Epipaleolithic (ca. 19-12 ka) assemblages from the Western Galilee/Mt. Carmel, Israel subregion. We test predictions from a Broad Spectrum Revolution model of the population dynamics of human foragers and their prey. The study emphasizes control over geographic variability and archaeological recovery and recording methods, as we analyze a time series that samples the Epipaleolithic more fully than have previous studies. This provides a new opportunity to examine human population and economic change in the long-term transition to sedentism and agriculture.We use the Mantel test to evaluate the significance of temporal trends in body-size-based big game diversity, as well as in diversity of small game prey types. Results demonstrate a highly significant decline through time in the relative abundance of medium and large big game, measured relative to small big game. This suggests that the apparent “gazelle specialization” by Late Epipaleolithic (Natufian) hunters reflects longer-term anthropogenic overexploitation of the largest prey types in the spectrum. While large and medium big game abundance declined, our results show small game increased in economic importance over time.Considered with associated climate change data, the results provide substantial support for the hypothesis that local human populations expanded rapidly in size after the Last Glacial Maximum (LGM). We suggest that following the post-LGM population pulse, human foragers adopted a shifting series of intensification strategies mediated by changes in residential mobility.     

An extinct species of Basella: pollen evidence from sediments (~80 ka) in Kerala,India

Abstract

The genus Basella belongs to family Basellaceae and is comprised of five species. Out of these, Basella alba is pantropical in distribution, B. paniculata is endemic to south-eastern Africa and the other three species viz. B. excavata, B. leandriana and B. madagascariensis are endemic to Madagascar. The palynological study of an organic layer buried ~80 ka in Chaganacherry, Kerala revealed a rich diversity of rainforest pollen and estuarine/marine palynomorphs indicating warm and humid climate coupled with sea level high stand. The Basella pollen recorded from this sediment shows intermediate characters of two extant Basella species. While it resembles B. paniculata in being pantocolpate (20), it shows affinity with B. alba in sexine characters. The recovered pollen was therefore, ascertained to be a new species, named here as B. keralensis sp. nov. The age correlation of the studied sediment was carried out by fingerprinting (Rare Earth Elements) of Youngest Toba Tuff (YTT) (glass shards) which spread in the atmosphere through a volcanic eruption in Sumatra ~74 ka and also with marine palynomorph markers correlating the interglacial Marine Isotopic Stage 5a (~80 ka). It is inferred that earlier, the genus Basella comprised of six species out of which Basella keralensis sp. nov. became extinct and until now neither the fossil record nor the extant form of this is known in records from any part of the World.     

Antiserum to prolactin lowers blood pressure (BP) in spontaneously hypertensive rats

The role of PRL in the development of hypertension in the SHR was examined by administering PRL antiserum to neonatal SHR. On days 2-7 post partum, male SHR were injected with 50 microliters/day of either antiserum to PRL (which chronically lowers plasma PRL), normal rabbit serum (NRS), or 0.9% NaCl. Heart rate, BP, and body weight were measured biweekly on weeks 6-14 of age. Anti-PRL lowered BP vs. NaCl on weeks 6, 8, 12, and 14 (range 7-17 mm Hg lower). NRS animals showed BP differences from the NaCl group only on weeks 6 and 14, with no consistent effect. Heart rates fell during the study in the NaCl and anti-PRL groups but not in the NRS group. Anti-PRL and NRS groups had higher heart rates than did the NaCl group. Body weights did not differ between groups except on week 14, when the NRS group weighed less than the NaCl group. These results suggest that while PRL is involved in BP regulation in the SHR, it is not involved in the pathogenesis of the genetic hypertension seen in the strain. In addition, the results suggest that the serum treatment may have caused heart damage which led to an elevation in the heart rates of the serum-treated groups.