百百鳞茎解除休眠与花期调控的研究

探讨了亚洲百合杂种系（Asiatic hybrids）‘新中心（Nove Cento）’在12℃冷藏过程中冷处理时间长短与花芽分化、花期调控之间的关系.结果表明：从冷藏开始至60 d,冷藏时间越长,鳞茎解除休眠所需时间越短,冷藏45 d以上,可完全解除鳞茎休眠;百合的花芽分化从冷藏45 d开始,栽植后30d基本完成;冷处理时间越长,百合植株开花越早,花茎越矮,而且还会出现二次抽薹开花的现象.     

低温和赤霉素对山丹鳞茎解除休眠与花期调控的影响

将山丹鳞茎在4℃分别冷藏处理15、30、45、60 d和冷藏处理45 d+赤霉素200mg/L,研究低温处理时间和赤霉素对鳞茎解除休眠与花期调控的影响.结果表明:冷藏时间越长,鳞茎解除休眠需要的时间越短.赤霉素处理相比于未施用赤霉素处理,鳞茎解除休眠需要的时间缩短3d,发芽到现蕾的时间缩短5d.赤霉素处理有助于山丹鳞茎快速解除休眠,提前开花.     

低温对解除百合鳞茎休眠和促进开花的作用

对目前国内外利用低温处理打破百合鳞茎休眠和促进开花等方面的研究进行了综述。近年来在百合鲜切花周年生产中, 通过低温解除鳞茎休眠, 提高百合鲜切花品质, 调节百合花期等方面的研究均有较大进展, 但有关百合鳞茎的休眠机理和开花机理的研究仍然比较薄弱。在休眠机理方面, 各激素间的互作关系以及分子水平上的研究是今后的重点。     

激素处理对百合鳞茎打破休眠及促进开花的效应

用GA350mg/L CEPA100mg/L KT100mg/L组合处理冷藏的百合鳞茎，能缩短冷藏时间，打破休眠，促进开花；加入丙酮溶剂可以提高激素处理的效果。     

百合二茬种球冷藏时间对成花的影响

以西伯利亚百合二茬种球为试材,在4℃的冷库内储藏,从冷藏36d开始,每10d取样种植在田间,研究植株田间生长的开花情况。结果表明:低温处理对于打破百合二茬种球的休眠,增加单枝的花苞数有着明显的促进作用;西伯利亚二茬种球比较合适的冷藏时间为67～97d,少于67d或多于97d都会不同程度的影响二茬花的成花率和切花品质。     

不同低温处理对百合鳞茎萌芽及花期的影响

探讨了不同低温处理:4、8、12℃对新铁炮百合‘雷山’(Lilium formolongi‘Raizan’)鳞茎萌芽及花期的影响。结果表明:低温冷藏期间,处理温度越高,顶芽在鳞茎内萌动越早,顶芽和新根的生长速度越快。经不同低温处理后栽植,百合鳞茎发芽所需时间和植株生育期长短分别与低温处理时间呈显著负相关关系,随着处理温度的升高和处理时间的延长,鳞茎发芽快且整齐,株高、茎粗、花期的一致性好。低温处理时间不足,会导致百合鳞茎发芽和植株生长不整齐,甚至栽植当年不能出苗,从而延长生育周期。在4~12℃条件下,解除‘雷山’鳞茎休眠的合适低温处理时间是5周。     

种球冷藏处理对欧洲水仙花期调控的影响

在苏南气候条件下,以欧洲水仙"小矮人"与"塔希提"2个品种的自繁种球为试材,探讨了不同时间低温(5~9℃)处理对欧洲水仙生长发育的影响与低温处理间鳞片与花芽的可溶性蛋白质与糖类的变化规律。结果表明:欧洲水仙种球在完成花芽分化后,早花品种"小矮人"在9月1日之前进行鳞茎冷藏处理,晚花品种"塔希提"在8月18日之前进行鳞茎冷藏处理,10月20日冷藏结束,可以实现元旦之前开花观赏;低温处理时间越长,开花越早,花葶越高。低温处理阶段,鳞片和花芽中的可溶性蛋白质含量随着低温处理时间的增加逐渐增加,且花芽中的可溶性蛋白质含量明显高于鳞片;鳞片和花芽中的可溶性糖含量均明显高于对照,且随着低温处理时间的增加,鳞片和花芽中的可溶性糖含量不断变化。该研究对欧洲水仙种球花期调控提供了理论和技术参考。     

长日照处理下‘雪球’海棠休眠特性和喷施6-BA对其萌芽及开花的影响

以‘雪球’海棠为试材,采用水培法研究了其在长日照处理下的休眠特性,并采用不同浓度细胞分裂素6-苄基腺嘌呤(6-BA)处理处于条件休眠的新梢,调查其花芽分化进程,以达到秋季开花的目的。结果表明:长日照处理下新梢的顶芽进入自发休眠时间在8月7日之后,而自然日照下树体自发休眠应发生在7月18日之前;长日照处理下喷施6-BA后共观察到116处萌芽,50处开花,开花数198朵。其中6-BA最适浓度为300 mg·L-1;花芽分化进程调查喷施6-BA对花芽分化有促进作用,喷施6-BA后长日照处理下‘雪球’海棠花芽分化进程快于自然光照。     

盆栽风信子年宵花花期调控影响因素

以风信子为试材,采用盆栽方法,研究了种球冷藏时间、品种对盆栽风信子年宵花花期调控的影响,以期为风信子年宵花生产提供参考。结果表明:冷处理对5个风信子品种的开花有促成作用,冷藏时间越长,开花时间越早。种球冷藏8～10周风信子能达到目标花期,对开花质量有促进作用,但冷藏11～12周开花质量反而下降。从品种来看,品种影响风信子盆栽年宵花上市时间。可以根据自然花期来调节风信子上市时间,从开花质量考虑,早花的品种适宜选"芬达",中花选"西贡小姐",晚花选"蓝色代夫特"比较适合做盆栽风信子年宵花生产。     

细叶百合休眠与解除SSH文库构建及其调控基因的初步筛选

 为了验证百合鳞茎休眠解除过程中基因表达的差异性，以细叶百合休眠鳞茎和休眠解除鳞 茎为材料，利用抑制消减杂交技术构建了百合鳞茎休眠及解除正、反向抑制消减文库。文库富集了差异 基因，消减效率符合要求，插入片段集中于250 ~ 1 000 bp 之间。对正、反向文库随机挑选阳性克隆测序， 各获得100 个表达序列标签（EST），在NCBI 上进行BLASTx 分析，并用KOBAS 系统将获得的unigene 定位到Pathways 中。分析结果表明，休眠文库ESTs 功能主要涉及胁迫响应方面，如苯丙氨酸代谢途径、 促分裂素原活化蛋白激酶途径等与休眠有关。休眠解除文库在糖代谢、激素响应及信号转导方面表达量 较高，如亚油酸代谢途径、淀粉及蔗糖代谢途径等参与了休眠解除过程。     

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.     

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.     

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.     

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.     

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.     

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.     

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.