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101.
Anthocyanins, present in fruits and vegetables as natural colorants, have been well characterized to possess bioactive properties. Anthocyanin components extracted from black rice (Oryza sativa L. indica) separated by gel filtration and identified using LC-MS were cyanidin 3-glucoside and peonidin 3-glucoside. A standardized extract of black rice pigmented fraction (BRE) containing known proportions of cyanidin 3-glucoside and peonidin 3-glucoside exhibited marked antioxidant activities and free radical scavenging capacities in a battery of in vitro model systems. Significant (p < 0.05) prevention of supercoiled DNA strand scission induced by reactive oxygen species (specifically, peroxyl radical and hydroxyl radicals) and suppression of the oxidative modification of human low-density lipoprotein was obtained with BRE. In addition, BRE reduced (p < 0.05) the formation of nitric oxide by suppressing inducible nitric oxide synthase expression in murine macrophage RAW264.7 cells, without introducing cell toxicity. The results of this study show that black rice contains anthocyanin pigments with notable antioxidant and anti-inflammatory properties for potential use in nutraceutical or functional food formulations.  相似文献   
102.
The effects of Potato leafroll virus (PLRV) isolates and inoculation method on the resistance to PLRV in potato clones and cultivars were investigated. In the season of inoculation, aphid inoculation resulted in higher proportions of infected plants and higher virus concentration in infected plants, as compared to graft inoculation. In these respects, grafting showed superiority over aphid inoculation in the tuber progeny of inoculated plants, though distinct dominance of aphid inoculation was observed for some tested clones. This leads to the conclusion that both methods should be applied as complementary tests for the efficient selection of highly resistant potato clones. For inoculations, two isolates of PLRV were applied, and one of them, isolate L7, was routinely used in screening breeding materials for resistance to the virus. The second isolate originated from plants of the highly resistant clone DW84-1457, which were incidentally infected with PLRV. The virus isolated from these plants was able to infect only specific clones, which were resistant to isolate L7. At the same time, potato clones with resistance derived from a source different from that present in DW84-1457, and standard susceptible and resistant cultivars, showed generally lower infection ratings after inoculation with the new isolate. This result suggests that the isolates may be different strains of PLRV. It is possible that under the strong selection pressure of resistance genes present in clone DW84-1457, a new isolate I-1457 could evolve the ability to overcome resistance to infection controlled by these genes.  相似文献   
103.
Summary Potato leaf roll virus (PLRV) was usually better transmitted byMyzus persicae from source plants kept during the pre-acquisition period at 12°C than from those kept at 26°C. Significantly more plants became infected when PLRV was acquired or inoculated at 26°C than at 12°C. The effect of temperature during the acquisition feeding period was found to be greater than that of temperature during the inoculation feeding period. PLRV was most frequently transmitted when it was both acquired and inoculated at 26°C.
Zusammenfassung Der Einfluss der Temperatur auf die übertragung des Kartoffel-Blattrollvirus (PLRV) durchMyzus persicae wurde in drei Perioden vor der Infektion der Pflanzen mit diesem Virus ermittelt: Vegetationsperiode vor Aufnahme durch die Virusquellen, Periode w?hrend der Virusaufnahme und der Inokulationsperiode. Die Untersuchungen wurden in temperaturkonstanten Kammern und im Gew?chshaus mit Pflanzen der Kartoffelsorte Osa als Quelle mit ausgew?hlten PLRV-Isolaten durchgeführt. Das Virus wurde aufPhysalis floridana und Kartoffelsorten unterschiedlicher Anf?lligkeit übertragen. Die H?ufigkeit der PLRV-übertragung durchM. persicae sank mit ansteigender Temperatur, zu welcher die Quellenpflanzen in der Periode vor der Virusaufnahme aufwuchsen (Abb. 2 und 3), obwohl dieser Effekt ausgeschaltet werden konnte, wenn das Virus durch die Blattl?use bei h?herer Temperatur aufgenommen wurde (Abb. 2). Die H?ufigkeit der PLRV-übertragung durch Blattl?use war nach einer Aufnahmeperiode bei 26°C signifikant gr?sser als bei 12°C (Abb. 2 bis 4). Der Einfluss h?herer Temperatur k?nnte stark genug sein, die Unterschiede in der PLRV-übertragung durch den Einfluss auf die Quellenpflanzen in der Vor-Aufnahmezeit zu eliminieren oder zu vermindern (Abb. 2). ?hnliches zeigte sich bei zunehmendem Alter der Quellenpflanzen (Abb. 1). Eindeutig mehr Pflanzen wurden infiziert, wenn PLRV bei 26°C anstatt 12°C inokuliert wurde (Abb. 3 und 4). Der Einfluss der Temperatur war in der Aufnahmeperiode gr?sser als in der Inokulationsperiode. Eine signifikant gr?ssere Population vonP. floridana und/oder Kartoffelpflanzen wurden infiziert, wenn PLRV durchM. persicae bei 26°C aufgenommen und inokuliert wurde (Abb. 3 und 4). Darüberhinaus war der Einfluss h?herer Temperatur, w?hrend beider Aufnahmeperioden angewendet, günstiger für visuelle und serologische (ELISA) Differenzierung der resistenten und anf?lligen Kartoffeln, gemessen an der H?ufigkeit infizierter Pflanzen (Abb. 4).

Résumé L'influence de la température sur la transmission du virus de l'Enroulement de la pomme de terre (VEPT) parMyzus persicae a été déterminée à trois périodes précédant l'infection des plantes par ce virus: période de végétation des plantes sources de virus avant acquisition (pré-acquisition), période d'acquisition, période d'inoculation. Les recherches ont été réalisées dans des salles à température contr?lée et en serre: des pommes de terre du cultivar Osa, infectées par des isolats sélectionnés de VEPT ont été utilisées comme plantes sources. Le virus a été transmis àPhysalis floridana et à des cultivars de pomme de terre de différentes sensibilités à l'infection par le VEPT. La fréquence de transmission du VEPT parM. persicae décro?t avec l'augmentation de la température à laquelle les plantes sources de virus ont été cultivées lors de la période de pré-acquisition (Figs 2 et 3), bien que cet effet ait pu être éliminé quand le virus a été prélevé par les pucerons à température plus élevée (Fig. 2). La fréquence de transmission du VEPT par les pucerons a été significativement plus grande après une période d'acquisition à 26° qu'à 12°C (Figs 2–4). L'effet de la température la plus élevée a pu être suffisamment fort pour supprimer ou réduire les différences de transmission du VEPT causées par l'effet de la température sur les plantes sources lors de la période de pré-acquisition (Fig. 2) ou par l'augmentation de l'age des plantes sources (Fig. 1). Un nombre significativement plus grand de plantes a été infecté quand le VEPT était inoculé à 26°C qu'à 12°C (Figs 3 et 4). L'effet de la température s'est avéré avoir une importance plus grande pendant la période d'acquisition que pendant la période d'inoculation. Une proportion significativement plus élevée deP. floridana et/ou de plants de pomme de terre a été infectée quand le VEPT était à la fois acquis et inoculé parM. persicae à 26°C (Figs 3 et 4). De plus, une température plus élevée appliquée pendant les deux périodes d'alimentation des pucerons s'est montrée plus favorable pour différencier visuellement et sérologiquement (ELISA) les pommes de terre résistantes, modérément résistantes et sensibles, lorsqu'on se base sur la fréquence des plantes infectées (Fig. 4).
  相似文献   
104.
Sea anemones are seemingly primitive animals that, along with corals, jellyfish, and hydras, constitute the oldest eumetazoan phylum, the Cnidaria. Here, we report a comparative analysis of the draft genome of an emerging cnidarian model, the starlet sea anemone Nematostella vectensis. The sea anemone genome is complex, with a gene repertoire, exon-intron structure, and large-scale gene linkage more similar to vertebrates than to flies or nematodes, implying that the genome of the eumetazoan ancestor was similarly complex. Nearly one-fifth of the inferred genes of the ancestor are eumetazoan novelties, which are enriched for animal functions like cell signaling, adhesion, and synaptic transmission. Analysis of diverse pathways suggests that these gene "inventions" along the lineage leading to animals were likely already well integrated with preexisting eukaryotic genes in the eumetazoan progenitor.  相似文献   
105.
In view of the lack of data on the effect of meloxicam (non-steroidal anti-inflammatory drug) on bovine γδ T cells (WC1+ cells) and very poorly recognized effects of dexamethasone (steroidal anti-inflammatory drug) on these cells, the purpose of the present study has been to determine the in vitro influence of these drugs on CD25highWC1+, CD25lowWC1+ and CD25?WC1+ lymphocytes of the peripheral blood of cattle. Peripheral blood mononuclear cells were treated with the drugs in concentrations reflecting their plasma levels achieved in vivo at therapeutic doses (dexamethasone 10?7 M; meloxicam 5 × 10?6 M) and at ten-fold lower concentrations. It was found out that percentages and absolute counts of CD25highWC1+ and CD25lowWC1+ cells increased in the presence of dexamethasone, and this effect was at least partly attributable to lower mortality of these cells, whose apoptosis was depressed by exposure to dexamethasone. It seems certain that this effect was not a result of increased multiplication of CD25highWC1+ and CD25lowWC1+ cells because their proliferation was reduced in the presence of dexamethasone. Exposure to this drug caused a rapidly occurring and lasting depletion of CD25?WC1+, which was at least partly due to their higher apoptosis. The results seem to suggest that impaired proliferation of these cells was responsible for a more profound expression of this disorder. Paradoxically, the percentage of cells producing IFN-γ, a proinflammatory cytokine, increased in the presence of dexamethasone, whereas the count of cells secreting the key anti-inflammatory and immunosuppressive cytokine, i.e. IL-10, declined. This effect was observed in all analyzed subpopulations of cells. Meloxicam did not interfere so drastically as dexamethasone with the functioning of WC1+ lymphocytes because it did not affect their apoptosis, proliferation, percentage or absolute count. With respect to the effect of meloxicam on counts of particular WC1+ lymphocyte subpopulations, it was only demonstrated that exposure to the drug was correlated with a transient and very weakly expressed decrease in the relative and absolute counts of CD25highWC1+ and CD25lowWC1+ cells, which was most probably a result of a temporary down-regulation of the expression of the CD25 molecule. In the presence of meloxicam, percentages of IFN-γ+CD25?WC1+ cells as well as cells producing IL-10 declined, an effect observed in all analyzed cell populations. These results suggest that care should be taken when administering this medication to animals with bacterial or viral infections, and we should avoid giving it to patients suffering from allergic or autoimmune disorders.  相似文献   
106.
The effects of the controlled reproduction of African catfish Heterobranchus longifilis after ovulation stimulation with carp pituitary homogenate (CPH; 4 mg kg?1; group I) or Ovopel (1/5+1 pellet kg?1; group II) were investigated. After the application of Ovopel, eggs were obtained from a higher percentage of females than after a CPH treatment (87.5% and 75.0% respectively). The statistically significant (P≤0.05) effect of ovulation stimulator was specified only in the case of the weight of eggs (expressed in grams and in percentage of female body weight), being higher in fish treated with Ovopel compared with CPH‐treated fish (176.02 g, 8.43% and 109.51 g, 5.48%). The quality of eggs expressed in percentage of live embryos after 24 h incubation was higher by 7.5% in fish treated with Ovopel. Latency period did not significantly affect the weight of eggs, fertilization percentage or percentage of living embryos after 24 h of egg incubation. However, the weight of eggs and percentage of living embryos after 24 h incubation were higher in fish spawning after 12 h latency (159.38 g and 85.30%) compared with the weight and quality of eggs obtained from females spawning after 14 h latency (126.15 g and 76.04%).  相似文献   
107.
Journal of Soils and Sediments - Organic matter improves soil fertility and water and thermal properties, but its content often decreases. This decrease may be mitigated by the addition of...  相似文献   
108.
The thermal properties, solubility characteristics, and crystallization kinetics of four commercial phytosterol preparations (soy and wood sterols and stanols) and their blends with corn oil were examined. Differential scanning calorimetry (DSC) revealed narrow melting peaks between 138 and 145 degrees C for all phytosterol samples, reversible on rescan. Broader and less symmetrical melting transitions at lower temperatures with increasing oil content were observed for two samples of phytosterol-oil admixtures. The estimated, from the solubility law, deltaH values (34.7 and 70.7 mJ/mg for wood sterols and stanols, respectively), were similar to the DSC experimental data. Fatty acid esters of soy stanols differing in the chain length of the acyl groups (C2-C12) exhibited suppression of the melting point and increase of the fusion enthalpy with increasing chain length of the acyl group; the propionate ester exhibited the highest melting point (Tm: 151 degrees C) among all stanol-fatty acid esters. Solubility of phytosterols in corn oil was low (2-3% w/w at 25 degrees C) and increased slightly with a temperature rise. Plant sterols appeared more soluble than stanols with higher critical concentrations at saturation. The induction time for recrystallization of sterol-oil liquid blends, as determined by spectrophotometry, depended on the supersaturation ratio. The calculated interfacial free energies between crystalline sediments and oil were smaller for sterol samples (3.80 and 3.85 mJ/m2) than stanol mixtures (5.95 and 6.07 mJ/m2), in accord with the higher solubility of the sterol crystals in corn oil. The XRD patterns and light microscopy revealed some differences in the characteristics among the native and recrystallized in oil phytosterol preparations.  相似文献   
109.
The method of in vitro selection for increased salt tolerance at the seed germination and early growth phase of strawberry seedlings is proposed. Clone Pau/27 was selected on medium containing 200 mM of NaCl from population obtained by free pollination of cv. ‘Paula2019;. Subsequently, on the same medium 18 salt tolerant clones were attained from the population of seeds collected from self pollinated Pau/27 plants. In the next step we examined the influence of a mild salt stress (75 mM of NaCl) on vegetative growth parameters of selected clones and two cvs.; ‘Paula2019; and ‘Senga Sengana’. All materials in the study on the basis of calculated indexes were divided into four groups differing in reaction to salt. First group (clustered together cv. ‘Paula’, Pau/27 and three second generation clones: Pau/27/11, Pau/27/24, Pau/27/30) represents sensitive genotypes. Second group, including ‘Senga Sengana’, Pau/27/06, Pau/27/10, Pau/27/12, Pau/27/13, Pau/27/15, Pau/27/18, Pau/27/20, Pau/27/21, Pau/27/26, Pau/27/27, Pau/27/31 and Pau/27/32 was designated tolerant. Third group contains only one highly tolerant clone Pau/27/08. The last group comprises two highly sensitive clones (Pau/27/01 and Pau/27/03). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
110.
The structure of natural subalpine spruce forest in the Zadná Pol’ana massif of the Western Carpathians was analysed. We focused on the variability of different aspects of stand structure, tree decay and regeneration processes in altitudinal gradient. We used systematic sampling, covering an area of 2 km2, to detect even subtle changes in stand structure within one forest type over a range of less than 200 m in elevation. Mean stand density was 290 trees (>7 cm DBH) per hectare, average basal area was 41 m2 ha−1, and the volume accumulation in living trees amounted to 500 m3/ha−1. Stand volume decreased by more than 50% between 1,260 and 1,434 m a.s.l. This means for an increase of altitude of 100 m that stand volume decreased by nearly 200 m3. Neither stand density nor basal area was related to elevation. Maximum tree height was strongly correlated to elevation, and it decreased on average by 6 m for each 100 m increment of altitude. No significant changes in the maximum spruce diameter were recorded in relation to the elevation gradient. Spatial distribution of trees was biased toward regularity at lower altitudes. Tree clustering increased with increasing altitude. The stock of coarse woody debris (CWD) decreased slightly along the altitudinal gradient, but changes were not significant. Density of spruce saplings and their number growing on CWD significantly increased across the elevation gradient. Despite the fact that the analysed forest tract was relatively large, highly variable in respect to environmental factors, and that stand volume, spatial structure, and tree height displayed strong variability along the elevation gradient, the diameter structure of stands and regeneration measures were uniform. Our results suggest that the recruitment of new trees in the Zadná Pol’ana subalpine spruce forest is not temporally continuous even at a scale of several square kilometres.  相似文献   
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