不同竹龄雷竹中硅及其他营养元素吸收和积累特征

在浙江省临安市的雷竹主产区,分别采集不同竹龄(1～4 a)和不同器官(叶、枝、秆)的雷竹样品,分析了Si和其他营养元素含量、吸收和积累特征,以及Si和其他营养元素之间的相互关系.结果表明： 雷竹各器官中C含量的大小顺序为竹秆>竹枝>竹叶,Si、N、P、K、Ca、Mg、Al、Fe和Mn含量的大小顺序为竹叶>竹枝>竹秆.除Mn主要积累在竹叶中外,其他9种营养元素主要积累在1年生雷竹的秆中.3～4年生雷竹竹叶的Si平均含量为13.66 g · kg^-1. 雷竹属于Si积累植物.随竹龄的增加,雷竹叶中的N、P、K和Mg含量减少,C、Al和Mn含量增加.雷竹对Si的吸收主要集中在第2年(57.1%),对N和K的吸收主要集中在前两年(67.7%～93.7%),此后N和K从植株体内流出,其流失量分别占总积累量的19.1%～39.1%.雷竹中Si与Ca、Al、Mn呈显著正相关,与N、P、K、Mg呈显著负相关.     

Inositol 1,4,5-trisphosphate-triggered Ca2+ release from bovine adrenal medullary secretory vesicles

The effect of inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) and calcium ionophore A23187 on Ca2+ release from bovine adrenal medullary secretory vesicles and microsomes was examined. Ins(1,4,5)P3 released 3.5 nmol of Ca2+/mg protein from secretory vesicles and 1.5 nmol of Ca2+/mg protein from microsomes as measured by a Ca2(+)-selective electrode. However, A23187 promoted Ca2+ uptake into vesicles while releasing Ca2+ from microsomes. Ins(1,4,5)P3-induced Ca2+ release from secretory vesicles was rapid, but the released Ca2+ was absorbed within 3 min during which the Ins(1,4,5)P3-releasable pools were refilled. The in situ calcium content of secretory vesicle measured by atomic absorption spectrometry was 112 +/- 6.3 nmol/mg protein indicating the potential importance of secretory vesicles as an intracellular Ca2+ store. The high Ca2(+)-buffering capacity of secretory vesicles is presumed to be due to the high Ca2(+)-binding capacity of chromogranin A, the major intravesicular protein, which has calsequestrin-like properties.     

Si在燕麦籽粒中的富集及其与其它8种元素的关系

通过环境扫描电镜结合X射线电子探针显微分析技术,对22个基因型的燕麦籽粒皮层、糊粉层、近糊粉层和颖果中部的Si含量进行测定.结果表明,Si元素在燕麦籽粒不同部位的含量有明显差异,皮层和糊粉层Si含量较高,近糊粉层和颖果中部含量较低,在颖果中Si主要富集在糊粉层中;而且不同基因型燕麦籽粒同一部位或不同部位Si的积累量也有较大差异,这可能是由遗传差异引起的.糊粉层中的Si含量影响着近糊粉层和颖果中部的Si含量.另外,籽粒不同部位Si含量与P、Ca、Mg、S、Al、Pb含量之间存在显著或极显著的非线性关系,颖果中部的Si含量与K、Cd含量之间不存在显著的非线性关系.说明Si在燕麦籽粒中富集的同时也影响着P、Ca、Mg、S、Al、Pb等元素的富集.     

猪卵母细胞体外成熟和体外受精卵表面元素的研究

本文应用X-射线能量色散技术对猪卵泡内卵母细胞,培养不同时间卵母细胞和体外受精卵进行了表面元素的定性和定量分析,结果表明,(1)在卵母细胞和受精卵的表面均含有Na、Mg、Al、Si、S、Cl、K、Ca和Fe元素;(2)A级卵母细胞随着体外培养,Ca的含量逐渐升高,而K的含量逐渐降低;(3)B、C级卵母细胞随着其培养Al、Ca~(2+)降低;(4)受精后卵表面的Ca显著升高。     

Ryanodine receptor type I and nicotinic acid adenine dinucleotide phosphate receptors mediate Ca2+ release from insulin-containing vesicles in living pancreatic beta-cells (MIN6)

We have demonstrated recently (Mitchell, K. J., Pinton, P., Varadi, A., Tacchetti, C., Ainscow, E. K., Pozzan, T., Rizzuto, R., and Rutter, G. A. (2001) J. Cell Biol. 155, 41-51) that ryanodine receptors (RyR) are present on insulin-containing secretory vesicles. Here we show that pancreatic islets and derived beta-cell lines express type I and II, but not type III, RyRs. Purified by subcellular fractionation and membrane immuno-isolation, dense core secretory vesicles were found to possess a similar level of type I RyR immunoreactivity as Golgi/endoplasmic reticulum (ER) membranes but substantially less RyR II than the latter. Monitored in cells expressing appropriately targeted aequorins, dantrolene, an inhibitor of RyR I channels, elevated free Ca(2+) concentrations in the secretory vesicle compartment from 40.1 +/- 6.7 to 90.4 +/- 14.8 microm (n = 4, p < 0.01), while having no effect on ER Ca(2+) concentrations. Furthermore, nicotinic acid adenine dinucleotide phosphate (NAADP), a novel Ca(2+)-mobilizing agent, decreased dense core secretory vesicle but not ER free Ca(2+) concentrations in permeabilized MIN6 beta-cells, and flash photolysis of caged NAADP released Ca(2+) from a thapsigargin-insensitive Ca(2+) store in single MIN6 cells. Because dantrolene strongly inhibited glucose-stimulated insulin secretion (from 3.07 +/- 0.51-fold stimulation to no significant glucose effect; n = 3, p < 0.01), we conclude that RyR I-mediated Ca(2+)-induced Ca(2+) release from secretory vesicles, possibly potentiated by NAADP, is essential for the activation of insulin secretion.     

Phosphorus availability influences elemental uptake in the mycorrhizal fungus Glomus intraradices, as revealed by particle-induced X-ray emission analysis

We investigated element accumulation in the arbuscular mycorrhizal fungus Glomus intraradices. Fungal spores and mycelia growing in monoxenic cultures were analyzed. The elemental composition was quantified using particle-induced X-ray emission (PIXE) in combination with scanning transmission ion microscopy. In the spores, Ca and Fe were associated mainly with the spore wall, while P and K showed patchy distributions and their concentrations were correlated. Excess of P in the hyphal growth medium increased the P and Si concentrations in spores and increased the K/Ca ratio in spores. Increased P availability decreased the concentration of Zn and Mn in spores. We concluded that the availability of P influences the uptake and accumulation of several elements in spores. It is demonstrated that PIXE analysis is a powerful tool for quantitative analysis of elemental accumulation in fungal mycelia.     

Studies on the Characteristic of Element Contents in the Dominant Plant Species of the Three gorges Region in China

The characteristics of the contents of 20 elements (Al, Fe, Mn, Ca, Mg, K, S, Si, P, Cd, Cu, Zn, Ti, Ni, Sr, Mo, Na, B, Cr, V) in 16 plant species collected from the Three Gorges Region in China were investigated. The average contents of Ca, K and Mg were higher than 1 000 μg·g-1, that of Al, P, Si, Fe, S and Mn ranged between 100—1 000 μg·g-1 and Ti, Cu, Ni, Cr, Mo, Cd and V were less than 10 μg·g- 1. The level of Na content was less than that of the reported. The main character of the element contents was of the Ca> K type. The contents of P, S, Ca and K in different plant samples showed a normal distribution pattern, while Al and Mn showed a elements lognormal distribution pattern. Plant species differed greatly in the element contents. On analyzing the coefficient of variation (C. V., % ), Al, Mn, Mg, Ni, Sr and Fe had higher C.V., while the C.V. of K, S, P, Cr, Cd and Cu was less than 60%, and Cu had the lowest C.V. The correlations between Al and Fe, Al and Ti, Al and Cr, A1 and V, Cd and Sr, Cd and Mo, Fe and V, Zn and Cr, Ni and Sr, Mg and Ni, Mo and Sr, Ca and Sr, Cr and Mo, Na and Mg, Na and P, P and S were statistically significant in different plant species. The classification of the 16 plant species and 20 dements by two-way indicator species analysis (TWINSPAN) method may suggest the difference in dement contents of the different plant species.     

青杨雌雄幼苗对主要矿质元素的吸收与分配差异

研究了一年生青杨雌雄幼苗及其不同部位对主要矿质元素（N、P、K、Ca、Mg）的吸收与分配特性及其性别间差异。结果显示：青杨雌株总P、总Ca的含量均显著高于雄株,总K含量则显著低于雄株。青杨雌雄幼苗叶片N含量均显著高于根、茎N含量,P、K、Mg含量分别表现出根＞茎＞叶、叶＞根＞茎、根＞叶＞茎的趋势。青杨雄株Ca含量呈现出根＞茎＞叶的趋势,但雌株却表现出根＞叶＞茎的趋势。同时,青杨雌株根P、叶Ca的含量均显著高于雄株,根Mg含量则显著低于雄株。此外,矿质元素含量比例在雌、雄幼苗根、茎、叶中均分别表现为Ca＞K＞N＞Mg＞P,Ca＞N＞K＞P＞Mg,N＞K＞Ca＞Mg＞P。结果表明,尽管矿质元素的比例模式在青杨雌雄幼苗的根、茎和叶中均相似,但其含量和分配在雌雄幼苗间具有显著的性别差异。     

Calcium-induced potassium pathway in sided erythrocyte membrane vesicles.

We have characterized the asymmetric effect of Ca2+ on passive K+ permeability in erythrocyte membranes, using inside out and right-side out vesicles. Ca2+, but not Mg2+, can induce an increase in K+ uptake in inside out vesicles. The half-maximal concentration of Ca2+ required to induce the K+ uptake is 0.2 mM, and the permeability increase is not specific for K+. Thus, the Ca2+- induced permeation process in inside out vesicles is changed from that in the energy-depleted intact cell which requires only micromolar concentrations of Ca2+ and is specific for K+. Removal of spectrin had no effect on the vesicle permeability increase due to Ca2+. Studies with N-ethylmaleimide show that the vesicle channel openings is mediated by a protein and passage is controlled by sulfhydryl groups; furthermore, the Ca2+-induced vesicle pathway is distinct from the normal channel for passive K+ leak in the absence of Ca2+. The protein is sensitive to its phospholipid environment since removal of easily accessible phospholipid head groups on the cytoplasmic face of the vesicles inhibits the Ca2+ -stimulated channel opening.     

Ca在水稻籽粒中的富集及其与其它7种元素的关系

通过环境扫描电镜结合X射线电子探针显微分析技术,对21种不同基因型的水稻籽粒颖壳内、外表面以及颖果表面、糊粉层、近糊粉层和米中部的Ca含量进行测定。结果表明,Ca元素在水稻籽粒不同部位的含量有明显差异,颖壳内外表面和颖果表面Ca含量较高,近糊粉层和颖果中部含量较低,在颖果中Ca主要富集在糊粉层中;而且不同基因型水稻籽粒同一部位或不同部位Ca的积累量也有较大差异,这可能是由遗传差异引起的。糊粉层中的Ca含量影响着颖壳外表面、颖果表面、近糊粉层和米中部的Ca含量。另外,籽粒不同部位Ca含量与P、Mg、K、Si、Al、Cd含量之间存在显著或极显著的非线性关系,与Pb含量之间不存在显著的非线性关系。说明Ca在水稻籽粒中富集的同时也影响着P、Mg、K、Si、M、Cd等元素的富集。     

The Content Levels of Chemical Elements of Plants in the Castanozems Typical Steppe Zone of Nei Monggol

The contents of N, P, K, Ca, S, Fe, Al, Si, Na, of 122 plant species in the XiLin River valley in Nei Monggol were studied. These results have shown as follows: 1. The contents of N, P. K, Ca, S, Fe, Al, Si, Na of 122 plants belong to three levels: N, K, Ca are 101-100(%) P, S, Si, Na are 100-10-1(%); Fe, A1 are 10-1-10-2(%). 2. The contents of chemical elements of 122 plants were divided into three levels (high, middle and low content). The range of the content and the number of plants in each level were obtained.     

Anion dependence of Ca2+ transport and (Ca2+ + K+)-stimulated Mg2+-dependent transport ATPase in rat pancreatic endoplasmic reticulum

Anion dependence of (Ca2+ + K+)-stimulated Mg2+-dependent transport ATPase and its phosphorylated intermediate have been characterized in both "intact" and "broken" vesicles from endoplasmic reticulum of rat pancreatic acinar cells using adenosine 5'-[gamma-32P] triphosphate ([gamma-32P]ATP). In intact vesicles (Ca2+ + K+)-Mg2+-ATPase activity was higher in the presence of Cl- or Br- as compared to NO3-, SCN-, cyclamate-, SO4(2-) or SO3(2-). Incorporation of 32P from [gamma-32P]ATP into the 100-kDa intermediate of this Ca2+ATPase was also higher in the presence of Cl-, Br-, NO3- or SCN- as compared to cyclamate-, SO4(2-) or SO3(2-). When the membrane permeability barrier to anions was abolished by breaking vesicle membrane with the detergent Triton X-100 (0.015%) (Ca2+ + K+)-Mg2+ATPase activity in the presence of weakly permeant anions, such as SO4(2-) and cyclamate-, increased to the level obtained with Cl-. However, 32P incorporation into 100-kDa protein was still higher in the presence of Cl- as compared to cyclamate-, indicating a direct effect of Cl- on the Ca2+ATPase molecule. The anion transport blocker 4,4-diisothiocyanostilbene-2,2-disulfonate (DIDS) inhibited (Ca2+ + K+)-Mg2+ATPase activity to about 10% of the Cl- stimulation level, irrespective of the sort of anions present in both intact and broken vesicles. This indicates a direct effect of DIDS on (Ca2+ + K+)-Mg2+ATPase. K+ ionophore valinomycin influenced (Ca2+ + K+)-Mg2+ATPase activity according to the actual K+ gradient: Ko+ greater than Ki+ caused inhibition, Ko+ less than Ki+ caused stimulation. From these results we conclude that Ca2+ transport into endoplasmic reticulum is coupled to ion movements which must occur to maintain electroneutrality.     

Properties of light and heavy vesicles simultaneously prepared from hog gastric mucosae

We obtained two kinds of vesicle preparations which were of different density from the same gastric mucosae of hogs stimulated with food before slaughter. Both kinds contained H+,K+-ATPase. The light vesicle preparation differed from the heavy vesicle preparation as follows: the KCl permeability across the membrane of heavy vesicles was larger than that of light vesicles, the actin (46-kDa peptide on SDS-polyacrylamide gel) content of heavy vesicles was much higher than that of light vesicles, and the H+,K+-ATPase activity of heavy vesicles was less sensitive to a monoclonal antibody raised against light vesicles (HK2032) than that of light vesicles. Furthermore, there was a drastic difference in reactivity to SCH 28080, which is an H+,K+-ATPase-specific inhibitor and reacts competitively with the K+-high affinity site. SCH 28080 is more potent in light vesicles than in heavy vesicles. These results suggest that the conformation of H+,K+-ATPase changed during the translocation from tubulovesicles to the apical plasma membrane. On the other hand, H+,K+-ATPase activities in both vesicles had similar pH and [K+] dependences.     

锥栗人工林结果初期养分动态特征及其模拟

应用系统分析和动态模拟的方法 ,对结果初期锥栗人工林的养分动态变化进行了分析和模拟 ,构建了林分树体地上部分、地下部分、土壤和凋落物 4个分室 ,测定了各分室的N、P、K、Ca、Mg各养分元素的现存库量 .土壤分室中N、P、K、Ca的现存量最高 ,分别达 311.4 7、11.4 36、2 18.9kg·hm-2 和 87 5 6kg·hm-2 ,Mg含量水平以凋落物分室最高 ,达 7.2 6 9kg·hm-2 .根据分室模型 ,计算了 5种元素各分室的流通量和流通率 ,并在不同营养元素补偿水平下 ,对系统各分室在未来 5年内的养分变化进行了模拟 ,结果表明 ,各元素每年最适宜的补充量为N 2 0kg·hm-2 、P 8kg·hm-2 、K 5kg·hm-2 、Ca 10kg·hm-2 、Mg 5kg·hm-2 .在这种补偿条件下 ,系统各分室间养分流动通畅 ,树体生长代谢正常 .研究结果可为锥栗人工林该期栽培营养管理提供依据     

兰竹荔枝叶片营养元素适宜含量的研究

本研究旨在探讨福建荔枝最重要品种兰竹的叶片营养元素适宜含量。统计分析表明,不同地点、年份对同一品种叶片元素含量存在明显的差异;荔枝叶片含氮量变异系数最小,并按磷、镁、钙、钾依次增大。本研究初步提出的丰产兰竹荔枝秋梢叶片营养元素适宜含量为:氮1.5—2.2％,磷0.12—0.18％,钾0.7—1.4％,钙0.3—0.8％,及镁0.18一0.88％;其叶片氮、磷、钾、钙、镁的适宜比例是1:0.08:0.57:0.30:0.12。上列指标可供荔枝营养诊断指导施肥之参考。     

Distribution of Six Synaptic Membrane Antigens in Subcellular Fractions of Rat Brain Cortex

Abstract: The subcellular distribution in rat brain cortex of six synaptic membrane antigens (56K, 58K, 62K, 63K, 64K, 66K) was studied by rocket immunoelectrophoresis, using antiserum to a highly purified synaptic plasma membrane fraction. Initial analysis of the insoluble portion of subcellular fractions showed that these antigens were also present in smooth microsomes, rough microsomes, and synaptic vesicles; that only traces were present in synaptic junctions; and that none was present in nuclei, mitochondria, and myelin. A trace amount of activity was also present in synaptic vesicle cytosol, but none in whole brain cytosol. Quantitative measurements of synaptic plasma membranes, smooth microsomes, and synaptic vesicles showed that all six antigens were present in synaptic plasma membranes and smooth microsomes, but that the 66K antigen was absent from synaptic vesicles. The 56K, 58K, 62K, 63K, and 64K antigens were present in highest concentration in synaptic plasma membranes, whereas the 66K antigen content was highest in smooth microsomes. Only the 58K, 62K, and 63K antigens were detectable in the membrane fraction of whole brain. Their enrichments in synaptic plasma membranes were 10.9, 5.4, and 5.9, respectively. We conclude that the 56K, 58K, 62K, 63K and 64K antigens are primary components of synaptic plasma membranes. The presence of synaptic plasma membrane antigens in smooth microsomes and synaptic vesicles probably represents material being actively transported, consistent with the hypothesis that proteins of synaptic plasma membranes and synaptic vesicles are transported via smooth endoplasmic reticulum.     

Complexin arrests a pool of docked vesicles for fast Ca(2+)-dependent release

Regulated exocytosis requires that the assembly of the basic membrane fusion machinery is temporarily arrested. Synchronized membrane fusion is then caused by a specific trigger-a local rise of the Ca(2+) concentration. Using reconstituted giant unilamellar vesicles (GUVs), we have analysed the role of complexin and membrane-anchored synaptotagmin 1 in arresting and synchronizing fusion by lipid-mixing and cryo-electron microscopy. We find that they mediate the formation and consumption of docked small unilamellar vesicles (SUVs) via the following sequence of events: Synaptotagmin 1 mediates v-SNARE-SUV docking to t-SNARE-GUVs in a Ca(2+)-independent manner. Complexin blocks vesicle consumption, causing accumulation of docked vesicles. Together with synaptotagmin 1, complexin synchronizes and stimulates rapid fusion of accumulated docked vesicles in response to physiological Ca(2+) concentrations. Thus, the reconstituted assay resolves both the stimulatory and inhibitory function of complexin and mimics key aspects of synaptic vesicle fusion.     

西北太平洋柔鱼耳石微量元素

耳石是头足类重要的硬组织之一,其微化学被用于头足类生活史的重建、群体划分等渔业生态学领域.本文根据我国鱿钓船2007年在西北太平洋海域生产期间采集的柔鱼样本,利用激光剥蚀电感等离子质谱法(laser ablation inductively coupled plasma mass spectrometry, LA-ICP-MS)分析了18枚柔鱼耳石的微量元素组成及其分布特性.结果表明： 柔鱼耳石主要由55种元素组成,含量最多的前10位元素分别为钙(Ca)、锶(Sr)、钠(Na)、磷(P)、钾(K)、硅(Si)、镁(Mg)、硼(B)、铁(Fe)和钡(Ba).方差分析表明,不同性别间柔鱼的Ca、Sr、Na、K、Mg、Fe、Ba的含量不存在显著性差异,但P、Si和B含量差异性明显;不同孵化期的群体间Sr和Na含量存在显著性差异,Ca、P、K、Si、Mg、B、Fe和Ba不存在显著性差异;不同耳石部位的Ca、Sr、Na、P、Mg和Ba含量存在显著性差异,而K、Fe、B和Si则不存在显著性差异.研究表明微量元素Sr和Na比较适合用于研究柔鱼的群体划分、洄游史推测等渔业生态学.
     

追施氮肥对桉树各器官养分浓度及贮量的影响

采用田间定位试验的方法,研究了追施氮肥对2年生桉树各器官生物量积累及养分浓度与贮量的影响.结果表明:与对照相比,追施氮肥使桉树生物量增加24.2%,其中树枝增幅最高,为38.2%,树叶最少.追施氮肥显著促进了桉树对养分的吸收,其增幅顺序为PKNMgCaSi;叶片中N、P、Mg、Si含量最高,K在树干中的贮量最大,树枝部位的养分浓度与贮量增加最为显著.桉树N、P、K养分以内循环为主,叶片凋落前分别有73.8%、79.1%和72.9%的N、P、K养分被转移到植株体内,其外循环量仅为全树贮量的14.8%、7.7%和8.6%;Ca、Mg、Si养分则以外循环方式为主,其中Ca最明显,树叶中89.2%的Ca随叶片凋落,其外循环通量占全树Ca总贮量的25.9%.     

中国南方生长于不同基质的天然林植物叶片元素含量特征比较

对比中国南方两个热带喀斯特森林、一个热带红树林和来自文献的一个亚热带常绿阔叶林植物叶片元素含量和计量特点。结果表明,受碳酸盐岩的影响,西双版纳和弄岗喀斯特森林植物叶片普遍富含Ca、Mg元素,因岩性差异,含有一定白云岩的弄岗地区的植物富集更多的Mg。西双版纳喀斯特森林存在K、Fe、Na、Zn元素的缺乏状况;由于白云岩矿物成分的特殊性和缓慢的风化速度,弄岗喀斯特植物有更高的叶片K、Zn、S含量。红树林植物富集P、Ca、Mg、Na、S元素,海水环境中大量的离子进入土壤被植物吸收利用,提高了红树的养分含量,并且在高盐环境下Na在叶片中大量富集。但是,红树植物表现缺乏Fe、Si、Zn。亚热带常绿阔叶林植物受酸性土影响大,Mn元素大量富集,P与Na的含量缺乏,并且相比其他生境,常绿阔叶林的N、P、Ca、Mg含量较低。西双版纳和弄岗的喀斯特森林植物叶片N/P比分别为14.27和18.26,说明前者受到N、P的共同限制,后者主要为P限制;红树植物N/P比为13.12,受N限制;常绿阔叶林植物本身严重缺P,N/P比为26.27,表现出明显的P限制。所研究的不同基质上的植物,叶片N与P元素之间均呈显著正相关,这种稳定的协同关系是植物适应环境的普遍规律。Ca与Mg两个二价阳离子元素在喀斯特森林和常绿阔叶林中为协同关系,而在红树林中则不存在相关性,分析表明Na盐胁迫下增加了Mg的吸收,改变了Ca、Mg的平衡关系。N与K元素在红树林和常绿阔叶林中为协同关系,而由于喀斯特环境中Ca、Mg协同影响了K的吸收,改变了N、K的协同关系。P与Zn在喀斯特森林和红树林中都表现出协同关系,这与两种元素在植物代谢过程中都参与了酶的合成有关。红树植物表现K和Mn的拮抗关系,而在喀斯特森林和常绿阔叶林中均未有相关性。S与P元素在弄岗喀斯特森林中表现出正相关,这种协同性可以帮助喀斯特植物缓解缺P的症状,而在高P的红树植物中没有相关性。研究结果对于森林生态系统的生物地球化学循环模拟和生态系统管理有重要参考意义。