不同预冷方式对甜樱桃贮藏过程中抗氧化酶活性的影响

为了研究预冷方式对甜樱桃贮藏过程中抗氧化酶活性的影响,本文以"红玛瑙"樱桃为材料,采用风冷、冰水预冷和臭氧化冰水预冷的方法,对采后"红玛瑙"樱桃在贮藏过程中的抗氧化酶活性进行了对比研究。结果表明,臭氧化冰水预冷处理能够明显提高贮藏过程中"红玛瑙"樱桃的抗性,在保藏15 d内能很好地抑制POD活性的上升,冷藏前期显著抑制了CAT活性的提升,并且有利于提升冷藏前20 d内SOD的活力。     

冷藏及货架期晚香蕉李品质和生理变化研究

以晚香蕉李为试材,研究了冷藏及同期冷藏后室温货架7天对果实的保鲜效果。结果表明,晚香蕉李为呼吸跃变型果实,分别于冷藏42天及冷藏28天室温货架7天时出现呼吸高峰,多酚氧化酶、过氧化物酶活性在呼吸高峰过后达到最大,呼吸高峰过后,果实品质快速劣变,果实失重、褐变、腐烂情况加剧;综合室温货架7天后果实保鲜效果,晚香蕉李在(0±0.5)℃条件下最长贮藏期应不超过42天,最长货架期不超过7天。     

板栗贮藏期坚果腐烂机理的研究

研究了板栗室温和低温贮藏下 ,坚果呼吸强度、呼吸代谢途径及其关键性酶活性、代谢产物、膜脂过氧化与腐烂的关系。结果表明 :板栗室温贮藏呼吸强度呈下降趋势 ,无呼吸跃变峰。冷藏初期 (入贮 10d) ,低温显著抑制坚果呼吸强度 ,但冷藏中后期 (入贮 10d后 ) ,其低温抑制作用逐渐解除。低温显著抑制了糖酵解 ,并维持较高水平的三羧酸循环 ,阻止丙酮酸进入发酵 ,减少乙醇等有害物质产生和累积。低温抑制了Cat、POD活性 ,保持较高的SOD活性 ,延缓膜脂过氧化 ,降低坚果腐烂率。提出了板栗贮藏期坚果腐烂首先是生理伤害 ,其次才是病菌侵染的观点。     

桃果贮藏技术简介

桃果贮藏技术简介一、冷藏：在通气冷藏库内进行，一般库温为０－３℃湿度８５一９０％，不同品种要求库温略有不同。但桃果经一段时间冷藏后，常使风味变淡，可在上市前，经２０℃条件下后熟２－３天加以解决。有些品种在冷藏期间会发生冷害，在低温环境中无症状表现，而...     

1–甲基环丙烯对番茄冷害的影响

 为探讨1–甲基环丙烯（1-MCP）处理对番茄果实低温贮藏期间冷害和抗病性的影响,以绿熟期的‘浙杂205’番茄为试材,用1 μL · L-1的1-MCP在20 ℃下处理番茄果实6 h,然后将其置于3 ℃冷藏14 d后转入20 ℃后熟16 d。结果发现,1-MCP处理加重了冷藏番茄后熟期间的冷害,但是延缓了硬度和可滴定酸度的下降,推迟了番茄红素的增加和乙烯峰的出现,诱导了多酚氧化酶和过氧化物酶活性,同时降低了几丁质酶和β–1,3–葡聚糖酶的活性。虽然1 μL · L-1的1-MCP处理延缓了冷藏番茄果实的后熟,却加重了番茄后熟期间冷害和病害的发生,不适合在番茄冷藏中应用。     

1-MCP对“藤牧1号”苹果贮藏品质的影响

为研究1-甲基环丙烯(1-MCP)对早熟苹果品种“藤牧1号”冷藏品质和冷藏后货架品质的影响,分别以0(对照)、500、1 000和1 500 nL/L的1-MCP处理“藤牧1号”苹果,对各处理苹果在0℃贮藏期间,以及在冷藏40和60 d后货架期间的品质进行了测定.结果表明:1-MCP抑制了“藤牧1号”苹果冷藏期间呼吸和乙烯释放速率;延缓了硬度和可滴定酸含量下降;延缓了苹果总酚含量、多酚氧化酶活性高峰的出现,抑制了丙二醛含量的升高;对可溶性固形物和维生素C含量影响不明显.此外,1-MCP还延迟了冷藏40和60 d后7d货架期间果实的硬度、可滴定酸含量的下降,明显提高了果实好果率.从整体看,1 500 nL/L的1-MCP维持“藤牧1号”苹果冷藏和货架期间品质的效果优于其它3个处理.     

不同贮藏方式对长蕊石头花主要营养成分含量的影响

以长蕊石头花为试材,研究了其营养成分含量在室温贮藏和冷藏条件下随时间变化的规律。结果表明:随着贮藏时间的延长,室温和冷藏2种贮藏方式中,长蕊石头花的VC、类胡萝卜素、叶绿素、可溶性蛋白含量均明显下降,可溶性糖含量先降低后升高。贮藏时间相同,室温处理下各营养成分含量低于冷藏处理。氨基酸含量呈上升趋势,且室温处理下氨基酸含量高于冷藏处理。     

贮藏温度对藤牧1号苹果果实保鲜效果影响研究

以藤牧1号苹果果实为试材,研究了贮藏温度对果实酶活性及理化性状的影响。结果表明:20℃和5℃温度条件下果实纤维素酶、PG、LOX、淀粉酶活性变化均表现前期逐渐增加,出现峰值后逐渐下降的变化趋势。20℃条件贮藏的果实不但纤维素酶、PG、LOX、淀粉酶活性始终高于5℃条件的果实,酶活性峰值出现时间也较早。果实贮藏期间,果肉原果胶含量逐渐降低,可溶性果胶含量逐渐增加,纤维素含量逐渐下降。20℃条件贮藏的果实的纤维素和果胶物质的含量变化率均高于5℃条件贮藏的果实。随着果实中纤维素和果胶物质的变化,果实逐渐软化,果肉硬度降低,失重率增加,品质下降。     

温度对“冰脆李”贮藏品质的影响

以"冰脆李"为试材,研究了1、5℃以及室温贮藏对"冰脆李"品质的影响。结果表明:冷藏过程中果实硬度、有机酸及维生素C含量均逐渐下降,而可溶性糖含量也上升缓慢,贮藏期延长,且1℃冷藏保鲜优于5℃。     

豇豆冷藏温度的研究初报

本试验研究了不同温度对豇豆冷藏效果及呼吸强度的影响。结果表明：豇豆冷藏的冷害临界温度是８℃，在低于８℃及８℃的条件下贮藏会发生冷害；９℃是豇豆冷藏的最适宜温度。     

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.     

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.     

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.     

Expression and significance of c-IAP2 and GAS1 in Hodgkin's lymphoma and anaplastic large cell lymphoma

AIM: To detect the expression of cytoplasmic inhibitor of apoptosis protein 2 (c-IAP2) and growth arrest-specific gene 1 (GAS1) in Hodgkin's lymphoma (HL) and anaplastic large cell lymphoma (ALCL) and to investigate the role of two genes in the pathogenesis of HL and ALCL.METHODS: HE staining, the antibodies CD30, CD15, CD45RO and CD20 were used to screen the cases of HL and ALCL from 288 cases of lymphoma. The clarified HL and ALCL were subjected for immunohistochemical staining by SP and ABC methods to analyze the expression of c-IAP2 and GAS1. RESULTS: ①The positive rate of c-IAP2 in HL was 25/26(96.1%) while that in ALCL was 6/19(31.6%), there presented statistic significance between HL and ALCL groups(P<0.05), meanwhile the positive rate of GAS1 showed statistic significance between HL and ALCL groups(P<0.05). ②Two cases were showed to be a mixed type combined with large tumor cells of HL and relatively smaller tumor cells of ALCL.CONCLUSION: ①The different expression of c-IAP2 and GAS1 in HL and ALCL implied a different mechanism of oncogenesis and the different defects in the pathway of signal transduction of apoptosis in HL and ALCL;②Few cases showed an overlap and a likely transitional state between HL and ALCL; ③The different expressing manner of GAS1 and c-IAP2 in HL and ALCL implied the potential marks for the differential dignosis of two kinds of lymphoma.     

Effects of patch attributes, barriers, and distance between patches on the distribution of a rock-dwelling rodent (Lagidium viscacia)

We tested whether size of habitat patches and distance between patches are sufficient to predict the distribution of the mountain vizcacha Lagidium viscacia a large, rock-dwelling rodent of the Patagonian steppe Argentina, or whether information on other patch and landscape characteristics also is required. A logistic regression model including the distance between rock crevices and depth of crevices, distance between a patch and the nearest occupied patch, and whether or not there was a river separating it from the nearest occupied patch was a better predictor of patch occupancy by mountain vizcachas than was a model based only on patch size and distance between patches. Our results indicate that a simple metapopulation analysis based on size of habitat patches and distance between patches may not provide an accurate representation of regional population dynamics if patches vary in habitat quality independently of patch size and features in the matrix alter connectivity. This revised version was published online in August 2006 with corrections to the Cover Date.     

Inhibitory β-adrenergic receptor in heart

β₃-adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β₃-adrenergic receptor are markedly distinguished from β₁-and β₂-adrenergic receptor subtypes. Recently studies show that myocardial β₃-adrenergic receptor mediates negative inotropic effect through Gi-protein/NO/cGMP pathway, the expression of β₃-adrenergic receptor and negative inotropic effect mediated by β₃-adrenergic receptor are increased in heart failure. However, because of the low expression of β₃-adrenergic receptor in the heart, the actual pathophysiological significance of β₃-adrenergic receptor remains unknown.