不同贮藏温度下兰州百合种球淀粉代谢与萌发关系初探

 不同的贮藏温度和贮藏时间，兰州百合鳞茎碳水化合物含量均有显著差异。顶芽6℃处理的淀粉含量最高，10℃处理最低；鳞茎盘的淀粉含量与之相反；鳞片的淀粉含量随着贮藏温度的降低而下降。鳞茎各部位可溶性糖的含量以及顶芽和鳞片的淀粉酶活性随着贮藏温度的升高而降低，鳞茎盘的淀粉酶活性为6℃处理最高，2℃处理最低。淀粉含量和淀粉酶活性呈极显著负相关。贮藏初期的34 d，顶芽在鳞茎内迅速发育，鳞茎内物质变化最活跃：淀粉含量明显下降，淀粉酶活性迅速增大，可溶性糖含量显著升高。顶芽和鳞茎盘的变化幅度大于鳞片，外部鳞片的变化幅度大于中部和内部鳞片。贮藏温度与贮藏时间之间的显著互作影响碳水化合物的代谢及鳞茎的萌发。在本试验中，2℃贮藏101 d为解除休眠的最佳处理。     

冷藏对郁金香鳞茎碳水化合物含量及淀粉酶活性的影响

以郁金香品种阿波罗、检阅、小黑人、普瑞斯玛、巴塞罗娜鳞茎为试材,对不同时间的冷藏处理郁金香鳞茎不同部位的可溶性总糖含量、淀粉含量、淀粉酶活力的变化进行研究。结果表明:郁金香鳞茎5个品种在冷藏处理期间可溶性总糖含量波动上升;淀粉含量冷藏初期下降明显,而后变化缓慢;淀粉酶活力均上升;相关分析表明淀粉与淀粉酶、可溶性总糖呈负相关,淀粉酶与可溶性总糖呈正相关。     

东方百合鳞茎冷藏解除休眠的养分代谢和酶活性变化

 以自繁的东方百合鳞茎为材料, 研究在2℃、5℃和8℃条件下, 鳞片中淀粉、可溶性总糖、还原糖含量和几种酶活性的变化。在8周的冷藏期内, 淀粉含量持续明显下降, 可溶性糖和还原糖含量增加, CAT、POD、SOD酶的活性在冷藏第1周下降极显著, 而α - 淀粉酶活性在第3周出现峰值, 自冷藏第4周后4种代谢酶活性均处于低水平。本试验中, 不同低温处理间的差异不大, 冷藏第7周后可解除休眠。     

低温解除休眠过程百合鳞片的氨基酸含量变化

对百合鳞片各部位在不同贮藏温度下的游离氨基酸含量和组分进行了定量分析。结果表明:百合鳞片各部位的游离氨基酸含量总体呈先上升后下降的趋势,冷藏的第4周游离氨基酸含量发生显著变化。游离氨基酸含量以内部鳞片>中部鳞片>外部鳞片。各部位鳞片以精氨酸的含量最高、变化最大,其次是谷氨酸、苏氨酸等,精氨酸、谷氨酸等谷氨酸族在百合鳞茎休眠解除过程中起重要作用。     

GA3、IBA以及变温处理对东方百合鳞片扦插繁殖及淀粉降解的影响

以东方百合‘Sorbonne’为试材,研究了GA3、IBA以及温度处理对鳞片扦插繁殖以及碳水化合物代谢的影响。结果表明：GA3处理可在较短时间内促进小鳞茎膨大,IBA处理使小鳞茎形成的时间延后,但可提高繁殖系数和整齐度。GA3、IBA分别结合5 ℃预处理可使小鳞茎质量显著增加,在较短时间内促进小鳞茎膨大;其中IBA 100 mg · L-1,1 h结合5 ℃预处理的鳞片繁殖系数和小鳞茎整齐度依次高于25 ℃与15 ℃变温培养及25 ℃恒温培养;GA3 100 mg · L-1,2 h结合5 ℃预处理获得的小鳞茎品质最佳。鳞片繁殖过程中,GA3、IBA结合各温度处理鳞片淀粉及总可溶性糖含量均呈下降趋势,尤其鳞片下部在25 ℃培养初期（20 d）下降幅度最大;IBA促进淀粉降解,结合低温处理的母鳞片较无低温处理的总可溶性糖含量低,为小鳞茎的诱导和形成提供了营养;5 ℃低温预处理促进GA3处理母鳞片淀粉的降解。     

寒地百合小鳞茎膨大发育过程中碳水化合物的变化研究

对2个百合品种的小鳞茎膨大发育过程中碳水化合物变化进行了研究。结果表明:百合鳞茎和新鳞茎中淀粉含量始终高于茎叶和根;小鳞茎中淀粉含量苗期前降低,苗期至半枯期持续增加,半枯期至采收期淀粉含量稍下降;鳞茎中可溶性糖含量于栽植期最高,栽植期至苗期迅速下降,此后其含量基本稳定;鳞茎中还原糖从栽植期至现蕾后24 d始终呈下降趋势,而后稳中有升;茎叶中淀粉和可溶性糖含量从栽植期至半枯期始终呈上升趋势;苗期后,根系中还原糖含量几乎始终呈上升趋势。     

摘顶处理对新铁炮百合鳞茎生理生化的影响

以自繁的新铁炮百合‘雷山'鳞茎为材料,研究不同摘顶处理对采收鳞茎生理生化指标的影响.结果表明:以现蕾期摘顶处理对鳞茎的影响最大,不仅使鳞茎周径增大,鲜重增加明显,而且鳞茎的干物质含量、淀粉含量、蛋白质含量以及还原糖含量都极显著增加,蛋白质含量的增加有助于提高其抗热性;过氧化物酶活性则极显著降低,在贮藏过程中其代谢活性低,比较有利于鳞茎贮藏.     

百合组培中鳞片处理及其颜色变化与鳞茎形成的关系

 研究了百合鳞片发育程度、切割段数、形态及生理变化、培养基的P 和K含量与鳞茎形成的关系。结果表明: 取中层鳞片、每片横切6 段的繁殖系数最高, 基部鳞片结鳞茎数最多, 且鳞茎发生最早。鳞片由基部向顶部繁殖系数递减。培养过程中鳞片颜色和形态变化依次为乳白色、浅黄、浅紫色、绿紫、鳞片干枯、鳞茎增大, 鳞片由浅黄变为绿紫色过程中叶绿素含量增加, 淀粉和可溶性糖含量下降。适当增加培养基中P、K的含量可提高鳞茎形成的数量和质量。     

不同低温冷藏条件下唐菖蒲球茎芽体及养分变化的研究

以当年收获唐菖蒲种球为试材,研究了不同低温冷藏处理对唐菖蒲球茎的芽体及体内所含还原性糖含量、可溶性糖含量、淀粉含量等养分的影响。结果表明:低温处理对唐菖蒲种球芽体长度及养分含量变化有显著影响,5℃下贮存唐菖蒲种球内新芽芽体伸长最快,可溶性糖含量和还原性糖含量最低,0℃下贮存唐菖蒲种球内淀粉含量降至最低。     

低温冷藏对番红花花芽中碳水化合物和氨基酸含量的影响

以番红花鳞茎为试材,进行不同变温处理,采用蒽酮比色法、3,5-二硝基水杨酸比色法和高速氨基酸自动分析仪,测定不同时间段花芽内可溶性糖、淀粉、淀粉酶和游离氨基酸含量,探讨低温冷藏与番红花发芽休眠解除之间的关系。结果表明:处理30 d后,可溶性糖含量急剧上升,淀粉含量急剧下降,α-淀粉酶和β-淀粉酶活性均表现出与可溶性糖含量相似的变化趋势;5℃/10℃处理30 d后花芽中可溶性蛋白质含量显著上升,精氨酸和脯氨酸含量显著下降;3个处理的谷氨酸含量均呈现整体上升趋势;多项测定指标之间呈显著或极显著相关。由此可知,番红花花芽经30 d低温处理后开始解除休眠,且以5℃/10℃处理效果最佳。     

Effects of radiation from 188Re on smooth muscle cell proliferation

AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β^-particles emission from ¹⁸⁸Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by ¹⁸⁸Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [³H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of ¹⁸⁸Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from ¹⁸⁸ Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G₀/G₁ arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation.     

Effect of L-Arg on plasma content of endothelin and expression of c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy

AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。     

Proteomic analysis between pathological scars and normal skin

AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars.     

Compositional and Functional Properties of Saskatoon Berry and Blueberry

Abstract

Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared.     

Cryopreservation of shoot apices of hawthorn in vitro cultures originating from East Asia

The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis.     

Metallothionein inhibits homocysteine-induced proliferation of rat vascular smooth muscle cells

AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [³-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10^-6-10^-4 mmol/L) stimulated [³-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [³-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10^-6-10^-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl₂ for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation.     

The effect of exposure on landscape scale soil surface temperatures and species distribution models

Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations, dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme temperatures (summer maximums, winter minimums). The correlation (r ²) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for 37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain the patchy distribution of many species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.