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61.
The defense response to several abiotic stresses has been compared in two tomato inbred lines issued from the same breeding program, one susceptible and the other resistant to Tomato yellow leaf curl virus (TYLCV) infection. The level of oxidative burst and the amounts of key regulatory stress proteins: pathogenesis-related proteins (PRs), heat shock proteins (HSPs) and mitogen-activated protein kinases (MAPKs) were appraised following treatments with NaCl, H(2)O(2), and ethanol. Significant differences in the response of the two tomato genotypes to these stresses have been found for HSPs and MAPKs patterns at the level of down-regulation but not activation. The higher abundance of HSPs and MAPKs in tomatoes resistant to TYLCV could result in enhanced defense capacity against abiotic stresses. 相似文献
62.
Fusion of oil bodies in endosperm of oat grains 总被引:1,自引:0,他引:1
Heneen WK Karlsson G Brismar K Gummeson PO Marttila S Leonova S Carlsson AS Bafor M Banas A Mattsson B Debski H Stymne S 《Planta》2008,228(4):589-599
Few microscopical studies have been made on lipid storage in oat grains, with variable results as to the extent of lipid accumulation in the starchy endosperm. Grains of medium- and high-lipid oat (Avena sativa L.) were studied at two developmental stages and at maturity, by light microscopy using different staining methods, and by scanning and transmission electron microscopy. Discrete oil bodies occurred in the aleurone layer, scutellum and embryo. In contrast, oil bodies in the starchy endosperm often had diffuse boundaries and fused with each other and with protein vacuoles during grain development, forming a continuous oil matrix between the protein and starch components. The different microscopical methods were confirmative to each other regarding the coalescence of oil bodies, a phenomenon probably correlated with the reduced amount of oil-body associated proteins in the endosperm. This was supported experimentally by SDS-PAGE separation of oil-body proteins and immunoblotting and immunolocalization with antibodies against a 16 kD oil-body protein. Much more oil-body proteins per amount of oil occurred in the embryo and scutellum than in the endosperm. Immunolocalization of 14 and 16 kD oil-body associated proteins on sectioned grains resulted in more heavy labeling of the embryo, scutellum and aleurone layer than the rest of the endosperm. Observations on the appearance of oil bodies at an early stage of development pertain to the prevailing hypotheses of oil-body biogenesis. 相似文献
63.
Krzysztof Schmidt Włodzimierz Jędrzejewski Henryk Okarma Rafał Kowalczyk 《Ecological Research》2009,24(1):207-214
Various species of large predators are reported to influence each other through interference or exploitation competition that
may affect demography and survival of the subordinate species. We analyzed spatial relationships between grey wolf (Canis lupus) and Eurasian lynx (Lynx lynx) in Białowieża Primeval Forest (BPF, eastern Poland) to determine how they partitioned the space. The wolves (n = 8) and lynx (n = 14) were radio-tracked in 1991–1999. Three wolves and seven lynx were radio-tracked simultaneously in 1994–1996. Territories
of wolf packs and home ranges of lynx overlapped considerably (76% of wolf territories and 50% of lynx home ranges, on average).
In three cases, their core areas were also overlapping. Wolf-lynx dyads with overlapping home ranges were simultaneously located
at distances from 0 to 28 km from each other. We found neither avoidance nor attraction between wolves and lynx occupying
the same areas. We concluded that in BPF, the two large predators coexist due to specialization on different preferred prey
and heterogeneous habitat. 相似文献
64.
Inhibitory effect of thalidomide on the growth, secretory function and angiogenesis of estrogen-induced prolactinoma in Fischer 344 rats 总被引:2,自引:0,他引:2
Stepień H Lawnicka H Mucha S Wagrowska-Danilewicz M Stepień B Siejka A Komorowski J 《Life sciences》2006,79(18):1741-1748
The process of angiogenesis has been found to be essential for the development of estrogen-induced pituitary prolactinoma in Fischer 344 rats. Thalidomide [(alpha-(N-phthalimido)-glutarimide] is known to be a potent immunomodulatory drug with antiangiogenic properties, but its effect on lactotroph cell secretory function and pituitary prolactinoma formation has not been described yet. The purpose of this study was to examine the effects of thalidomide on secretion of prolactin (PRL) and vascular endothelial growth factor (VEGF), cell proliferation, apoptosis and angiogenesis within the anterior pituitary gland in long-term diethylstilboestrol (DES)-treated male F344 rats in vivo and in vitro. It was found that DES sharply increased serum PRL and VEGF levels. On the other hand, simultaneous treatment of F344 rats with thalidomide for the last 15 days of the experiment attenuated the stimulatory effect of DES on PRL and VEGF secretion. It also diminished prolactin cell proliferation evaluated as the number of proliferating cell nuclear antigen (PCNA)-positive stained cell nuclei and increased the number of apoptotic bodies determined by the terminal deoxynucleotidyl-mediated dUTP nick-end labeling (TUNEL) method in sections of the DES-induced pituitary prolactinoma. The density of pituitary microvessels evaluated by microscopic counting of CD-31-positive blood vessels was also diminished by the tested drug. In addition, thalidomide (10(-4) to 10(-6) M) inhibited cell proliferation, prolactin and VEGF secretion from rat pituitary prolactinoma cells cultured in vitro. In conclusion, our results provide strong evidence for the antiprolactin and antitumor activity of thalidomide in experimentally DES-induced pituitary adenoma. 相似文献
65.
66.
Barton HJ 《Biological trace element research》2011,143(2):637-658
The population of about 300 6-year-old preschool children was studied for lead (Pb) and cadmium (Cd) in deciduous teeth, scalp
hair, and capillary blood. Zinc (Zn) content in hair was also measured due to its possible interferences with the elements
studied. The Pb and Cd contents were measured by graphite furnace atomic absorption spectrometry with Zeeman background correction,
and Zn, by flame method. Metal levels found were comparable to those in European countries. Positive correlations between
Pb and Cd in the same and different tissues were widespread (r = 0.23–0.68). A positive correlation was found between Pb in teeth and blood (r = 0.65, p < 0.001). Pb blood threshold 100 μg L−1 referred to 2.6 μg g−1 Pb in teeth. Predictability of this Pb teeth limit was 14% vs. 5% for Pb blood. Strong negative correlation was found between
hair Pb and Zn (r = −0.68, p < 0.001). Enhanced Cd and Zn levels in hair were associated with the household drinking water hardness. The associations
with some other environmental and behavioral factors were also presented and discussed. The results proved the advantage of
analysis of primary teeth for Pb exposure screening of preschool children. 相似文献
67.
Environmental stresses at particularly vulnerable stages during crop development may severely diminish productivity. At temperature
of 10 °C or below cultivated tomato germinate slowly if at all. In this study, seven tomato genotypes bred at the Research
Institute of Vegetable Crops were evaluated for germination time at 10 °C. Analysis identified that one genotype which has
L. chilense in its pedigree, germinated most rapidly while four other genotypes germinated slower. After 21 days, four out of five of
the genotypes resulted in seed germination from 81 to 98 %. 相似文献
68.
Janina Gajc-Wolska Henryk Skąpski Jolanta A. Szymczak 《Acta Physiologiae Plantarum》2000,22(3):369-373
The physical and sensory characteristics of tomato fruits (cf. Gajc-Wolska et al.: Physical and sensory characteristics of the fruits …, this issue) were supplemented by total sugars and titratable acid
analysis and flavor. The instrumental and sensory methods were highly statistically correlated. Comparison of cultivars always
requires that physical and chemical analysis of tomato fruit quality should always include results of sensory evaluation. 相似文献
69.
Michel Bataille Leslie D. Pettit Ian Steel Henryk Kozlowski Tomasz Tatarowski 《Journal of inorganic biochemistry》1985,24(3):211-221
Syntheses and the results of a potentiometric and spectrophotometric study at 25°C and an ionic strength of 0.10 mol dm?3 (KNO3) of the H + and Cu2+ complexes of two pairs of tetra- and octapeptides are reported. The peptides, Gly-Gly-Pro-Gly and (Gly-Gly-Pro-Gly)2, and Gly-Gly-Pro-Lys and (Gly-Gly-Pro-Lys)2, are models for the biologically active octapeptide with antitumor activity, dog tuftsinyltuftsin. The results clearly demonstrate participation of the ?-NH2 group of -Lys- in metal ion coordination from below pH 6 and, with the octapeptides at high pH, suggest the presence of a bent conformation with a large chelate ring spanning the two ends of the peptide chain. 相似文献
70.
Cezary Watala Jacek Golański Henryk Witas Ryszard Gurbiel Krzysztof Gwo?dziński Zygmunt Trojanowski 《The international journal of biochemistry & cell biology》1996,28(12):1393-1403
The erythrocyte deformability, which is related to erythrocyte internal viscosity, was suggested to depend upon the physico-chemical properties of haemoglobin. In the present study we employed ESR spectroscopy in order to explore further the extent to which the in vivo or in vitro glycation and/or glycoxidation might affect haemoglobin structure and conformation. We revealed that under both in vivo and in vitro conditions the attachment of glucose induced a mobilization of thiol groups in the selected domains of haemoglobin molecules (the increased h+1/h0 parameter of maleimide spin label, MSL; 0.377 ± 0.021 in diabetics vs 0.338 ± 0.017 in controls, n = 12, P < 0.0001). The relative rotational correlation time (τc) of two spin labels, TEMPONE and TEMPAMINE, respectively, in erythrocyte insides (5.22 ± 0.42 in diabetics, n = 21 vs 4.79 ± 0.38, n = 16 in controls, P < 0.005) and in the solutions of in vitro glycated haemoglobin, were increased. Neither oxidation nor crosslinking of thiol groups was evidenced in glycated and/or oxidized haemoglobin. In addition, erythrocyte deformability was found to be reduced in type 2 diabetic patients (6.71 ± 1.08, n = 28 vs 7.31 ± 0.96, n = 21, P < 0.015). In conclusion, these observations suggest that: the attachment of glucose to haemoglobin might have decreased the mobility of the Lys-adjacent Cys residues, thus leading to the increased h+1/h0 parameter of MSL. Such structural changes in haemoglobin owing to non-enzymatic glycosylation may contribute to the increased viscosity of haemoglobin solutions (r = 0.497, P < 0.0035) and the enhanced internal viscosity of diabetic erythrocytes (r = 0.503, P < 0.003). We argue that such changes in haemoglobin, and consequently in red blood cells, might contribute to the handicapped oxygen release under tissue hypoxia in the diabetic state. 相似文献