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61.
Giedrė Kacienė Romualdas Juknys Irena Januškaitienė 《Archives of Agronomy and Soil Science》2017,63(8):1037-1048
The aim of this study is to investigate the possibilities and the mechanisms of spring barley (Hordeum vulgare L.) cross-adaptation to different heavy metals after hardening with ozone (O3), drought and UV-B radiation. Dry shoot biomass, accumulation of superoxide (O2˙?) and malondialdehyde (MDA), and activities of enzymes superoxide dismutase (SOD), glutathione reductase (GR) and catalase (CAT) were measured after hardening and heavy metal treatments. Seedlings, exposed to ozone and drought prior to copper (Cu) treatment, showed significantly increased tolerance to this heavy metal. The most possible causes of cross-adaptation to this redox-active heavy metal, which triggered very strong oxidative stress in nonhardened barley seedlings, were increased CAT activity, mitigation of O2˙? accumulation and lipid peroxidation. Cross-adaptation to cadmium (Cd) was induced only by drought hardening. In this case, however, adaptation had lower effect on antioxidative enzymes, did not altered O2˙? accumulation and even slightly increased the intensity of lipid peroxidation. The study reveals that stimulation of CAT activity and mitigation of oxidative stress are the main reasons for plant adaptation to Cu; whereas cross-adaptation to Cd, heavy metal with much lower oxidative capacity, is determined by the mechanisms that are not related to oxidative stress directly. 相似文献
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Salvatori D Vincenzetti S Maury G Gosselin G Gaubert G Vita A 《Comparative immunology, microbiology and infectious diseases》2001,24(2):113-122
A series of beta-D- and beta-L-cytidine analogues were evaluated for their inhibitory effect on the replication of maedi-visna virus (MVV) strains KV1772 and MV1514 cultured on sheep choroid plexus cells and the sheep chondrocyte cell line G81092, respectively. Eleven cytidine analogues were selected for the anti-viral test. Five of them belong to the family of the 2',3'-dideoxycytidine analogues, well known for their activity against human immunodeficiency virus (HIV). The others, all newly synthesized, were potential anti-viral and/or anti-leukemic agents. None of the compounds under study had a toxic effect in both anti-viral assay systems up to a 300 microM concentration. Based on the cytopathic effects (CPE), the virus replication was completely inhibited by the five 2',3'-dideoxycytidine analogues at a concentration of 50 microM, whereas the others six newly synthesized compounds induced titre reductions of 4-5 log units. The effective concentration causing 50% reduction of CPE (EC50) was of 5 microM for the five 2',3'-dideooxycytidine analogues and for beta-L-XyloFc, whereas the value of 50 microM was found for the b-L-XyloC and the four 5-azacytidine compounds tested. All these data reveal a good correlation between inhibition of MVV replication by several nucleoside cytidine analogues and their reported anti-HIV activity. 相似文献
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F. Abbate R. Laura U. Muglia G. Vita P. Bronzetti 《Anatomia, histologia, embryologia》1993,22(4):348-354
The ultrastructural modifications that occur on the ependymal surface of the lateral ventricles of prenatal rabbit brains at 25, 27, 29 days of pregnancy, of term fetuses (30–31 days) and of 5, 10, 15 day old newborn rabbits, were studied by a SEM. On the ependymal surface the cilia, usually associated in tufts and the microvilli, variable in size and number, that surround them, show a rate of development correlated to the age. The results show the early differentiation of the surface features commensurated with early cerebrospinal fluid (CSF) functioning. 相似文献
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Freeze tolerance and physiological changes during cold acclimation of giant reed [Arundo donax (L.)] 下载免费PDF全文
Arundo donax L. (Poaceae), giant reed, is a rhizomatous shrubby grass that is cultivated in subtropical and warm temperate regions for a multitude of uses. Recently, it has been identified as a leading sustainable, non‐food crop for lignocellulosic biofuels due to its low ecological and agronomic demands. Lack of cold hardiness may limit its diffusion into colder areas of the transition zone. The objectives of this study were to (i) quantify freeze tolerance (LT50) of cold‐acclimated and non‐acclimated Arundo donax L. plants using reproducible, controlled environment conditions, (ii) determine the effect of prolonged exposure to freeze stress on tolerance by keeping plants at a constant, sublethal temperature and (iii) study the relationship of non‐structural carbohydrates (total soluble sugars, glucose, fructose and sucrose) and proline accumulation with cold hardiness. In vitro‐propagated plants of the Honduran and Hungarian ecotypes of Arundo donax L. were chosen for this study. Cold acclimation treatment was imposed for 1 week using a controlled environment chamber set at 10°C and with a 12‐h photoperiod of 200 μmol m?2 s?1 photosynthetically active radiation. Freeze tolerance ranged from ?12·8°C (Honduran) to ?16·4°C (Hungarian ecotype). In all the organs analysed, total soluble sugars significantly increased during cold acclimation, with concentrations between 1·8‐ and 4·7‐fold higher than in non‐acclimated plants. The higher concentrations of sugars and proline in cold‐acclimated plants were positively associated with enhanced giant reed freeze tolerance (2·9°C lower). Our results confirm that during cold acclimation, metabolic changes related to increased freezing tolerance occur in giant reed. 相似文献
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Anna Carbone Barbara Parrino Gloria Di Vita Alessandro Attanzio Virginia Spanò Alessandra Montalbano Paola Barraja Luisa Tesoriere Maria Antonia Livrea Patrizia Diana Girolamo Cirrincione 《Marine drugs》2015,13(1):460-492
Two new series of nortopsentin analogues, in which the imidazole ring of the natural product was replaced by thiazole and indole units were both substituted by 7-azaindole moieties or one indole unit was replaced by a 6-azaindole portion, were efficiently synthesized. Compounds belonging to both series inhibited the growth of HCT-116 colorectal cancer cells at low micromolar concentrations, whereas they did not affect the viability of normal-like intestinal cells. A compound of the former series induced apoptosis, evident as externalization of plasma membrane phosphatidylserine (PS), and changes of mitochondrial trans-membrane potential, while blocking the cell cycle in G2/M phase. In contrast, a derivative of the latter series elicited distinct responses in accordance with the dose. Thus, low concentrations (GI30) induced morphological changes characteristic of autophagic death with massive formation of cytoplasmic acid vacuoles without apparent loss of nuclear material, and with arrest of cell cycle at the G1 phase, whereas higher concentrations (GI70) induced apoptosis with arrest of cell cycle at the G1 phase. 相似文献
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Cludio C. Maretti Adriana R. Leo Ana Paula Prates Eliane Simes Ricardo B.A. Silva Ktia T. Ribeiro Leonardo Geluda Manoel S. Sampaio Fernanda F.C. Marques Anna C. Lobo Luís H. de Lima Leonardo M. Pacheco Warwick A. Manfrinato Antnio Q. Lezama Matheus T.P. Couto Paula M. Pereira Moara M. Giasson Paulo H.M. Carneiro Aldízio L. de Oliveira Filho Bernardo F.A. Brito Maurício S. Pompeu Guilherme F. Dutra Mara C. Nottingham Giovanna Palazzi Fabiana O. Hessel Andr L. Lima Bruna De Vita S. Santos Rodrigo Medeiros Marcelo M. Oliveira Mauro O. Pires Mnica Assad Mariana G. Pereira Marcelo R. Kinouchi Rosana J. Subir 《水产资源保护:海洋与淡水生态系统》2019,29(Z2):44-70
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P. De Vita M. S. Serrano N. Luchi P. Capretti A. Trapero M. E. Sánchez 《Forest Pathology》2010,40(2):129-132
Abies pinsapo, a rare fir found in the southernmost mountain region of Spain, is severely affected by Heterobasidion abietinum. It was hypothesized that spread of the disease might be favoured by woody species growing in the same habitat. In order to evaluate this hypothesis, artificial inoculation tests were performed on other potential hosts forming the tree cohort species with A. pinsapo. Inoculation test on seedlings demonstrated that H. abietinum was able to colonize stems of Pinus halepensis, P. pinaster and Quercus ilex subsp. rotundifolia, but failed on Q. faginea. Both Pinus species were colonized to a similar extent as the natural host, but Q. ilex subsp. rotundifolia showed a significantly lower susceptibility than conifers. These results suggest that Pinus spp. growing in mixed stands with A. pinsapo might favour spread of H. abietinum. As a consequence, natural replacement of pure A. pinsapo stands by mixed forest Abies‐Quercus should be facilitated. 相似文献
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María Socorro Serrano Pilar Fernández-Rebollo Paolo De Vita María Dolores Carbonero Antonio Trapero María Esperanza Sánchez 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(2):149-152
Phytophthora cinnamomi is an aggressive pathogen on Lupinus luteus (yellow lupin), causing root rot, wilting and death of this crop, common in oak-rangeland ecosystems ('dehesas') in south-western
Spain. The oomycete, the main cause of Quercus decline in the region, was isolated from roots of wilted lupins in the field. Artificial inoculations on four cultivars of
L. luteus reproduced the symptoms of the disease, both in pre- and post-emergence stages, recovering the pathogen from necrotic roots.
These results suggest the potential of yellow lupin as inoculum reservoir for the infection of Quercus roots. This is the first report of P. cinnamomi as root pathogen of L. luteus. 相似文献