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941.
942.
Vilizzi Lorenzo Copp Gordon H. Adamovich Boris Almeida David Chan Joleen Davison Phil I. Dembski Samuel Ekmekçi F. Güler Ferincz Árpád Forneck Sandra C. Hill Jeffrey E. Kim Jeong-Eun Koutsikos Nicholas Leuven Rob S. E. W. Luna Sergio A. Magalhães Filomena Marr Sean M. Mendoza Roberto Mourão Carlos F. Neal J. Wesley Onikura Norio Perdikaris Costas Piria Marina Poulet Nicolas Puntila Riikka Range Inês L. Simonović Predrag Ribeiro Filipe Tarkan Ali Serhan Troca Débora F. A. Vardakas Leonidas Verreycken Hugo Vintsek Lizaveta Weyl Olaf L. F. Yeo Darren C. J. Zeng Yiwen 《Reviews in Fish Biology and Fisheries》2019,29(3):529-568
Reviews in Fish Biology and Fisheries - The freshwater Fish Invasiveness Screening Kit (FISK) has been applied in 35 risk assessment areas in 45 countries across the six inhabited continents (11... 相似文献
943.
Franzetti E Huang ZJ Shi YX Xie K Deng XJ Li JP Li QR Yang WY Zeng WN Casartelli M Deng HM Cappellozza S Grimaldi A Xia Q Feng Q Cao Y Tettamanti G 《Apoptosis : an international journal on programmed cell death》2012,17(3):305-324
Although several features of apoptosis and autophagy have been reported in the larval organs of Lepidoptera during metamorphosis, solid experimental evidence for autophagy is still lacking. Moreover, the role of the two processes and the nature of their relationship are still cryptic. In this study, we perform a cellular, biochemical and molecular analysis of the degeneration process that occurs in the larval midgut of Bombyx mori during larval-adult transformation, with the aim to analyze autophagy and apoptosis in cells that die under physiological conditions. We demonstrate that larval midgut degradation is due to the concerted action of the two mechanisms, which occur at different times and have different functions. Autophagy is activated from the wandering stage and reaches a high level of activity during the spinning and prepupal stages, as demonstrated by specific autophagic markers. Our data show that the process of autophagy can recycle molecules from the degenerating cells and supply nutrients to the animal during the non-feeding period. Apoptosis intervenes later. In fact, although genes encoding caspases are transcribed at the end of the larval period, the activity of these proteases is not appreciable until the second day of spinning and apoptotic features are observable from prepupal phase. The abundance of apoptotic features during the pupal phase, when the majority of the cells die, indicates that apoptosis is actually responsible for cell death and for the disappearance of larval midgut cells. 相似文献
944.
研究表明化疗药物作用于肿瘤细胞后可有效激发免疫应答,这与肿瘤细胞的性质和化疗药物有关。该研究主要探讨阿霉素(adriamycin,ADM)处理小鼠宫颈癌u14细胞获得的肿瘤抗原致敏树突状细胞(dendriticceils,DCs)的免疫应答及对肿瘤的杀伤效应。分别应用ADM和反复冻融法处理小鼠宫颈癌U14细胞,取其离心上清液,致敏小鼠骨髓来源的DC,观察DC诱导的淋巴细胞增殖反应和细胞毒性T淋巴细胞(cytotoxicTlymphocyte,CTL)对宫颈癌细胞的细胞毒效应。结果显示:ADM处理的U14细胞抗原致敏后的DC组所激发和扩增的T细胞数及对宫颈癌细胞的杀伤效果显著高于对照组(P〈0.05)。因而提示ADM处理的肿瘤抗原能有效地致敏DC并产生抗肿瘤免疫效应。 相似文献
945.
Fang-Li Luo Kerstin A. Nagel Bo Zeng Ulrich Schurr Shizue Matsubara 《Annals of botany》2009,104(7):1435-1444
Background and Aims
Concomitant increases in O2 and irradiance upon de-submergence can cause photoinhibition and photo-oxidative damage to the photosynthetic apparatus of plants. As energy and carbohydrate supply from photosynthesis is needed for growth, it was hypothesized that post-submergence growth recovery may require efficient photosynthetic acclimation to increased O2 and irradiance to minimize photo-oxidative damage. The hypothesis was tested in two flood-tolerant species: a C3 herb, Alternanthera philoxeroides; and a C4 grass, Hemarthria altissima. The impact of low O2 and low light, typical conditions in turbid floodwater, on post-submergence recovery was assessed by different flooding treatments combined with shading.Methods
Experiments were conducted during 30 d of flooding (waterlogging or submergence) with or without shading and subsequent recovery of 20 d under growth conditions. Changes in dry mass, number of branches/tillers, and length of the longest internodes and main stems were recorded to characterize growth responses. Photosynthetic parameters (photosystem II efficiency and non-photochemical quenching) were determined in mature leaves based on chlorophyll a fluorescence measurements.Key Results
In both species growth and photosynthesis recovered after the end of the submergence treatment, with recovery of photosynthesis (starting shortly after de-submergence) preceding recovery of growth (pronounced on days 40–50). The effective quantum yield of photosystem II and non-photochemical quenching were diminished during submergence but rapidly increased upon de-submergence. Similar changes were found in all shaded plants, with or without flooding. Submerged plants did not suffer from photoinhibition throughout the recovery period although their growth recovery was retarded.Conclusions
After sudden de-submergence the C3 plant A. philoxeroides and the C4 plant H. altissima were both able to maintain the functionality of the photosynthetic apparatus through rapid acclimation to changing O2 and light conditions. The ability for photosynthetic acclimation may be essential for adaptation to wetland habitats in which water levels fluctuate.Key words: Aerenchyma, Alternanthera philoxeroides, flooding, growth, Hemarthria altissima, low light, photosynthesis, shade, submergence, waterlogging, wetland plant 相似文献946.
Astrocytes participate in brain functions through Ca2+ signals, including Ca2+ waves and Ca2+ oscillations. Currently the mechanisms of Ca2+ signals in astrocytes are not fully clear. Here, we present a computational model to specify the relative contributions of different Ca2+ flows between the extracellular space, the cytoplasm and the endoplasmic reticulum of astrocytes to the generation of spontaneous Ca2+ oscillations (CASs) and cortical spreading depression (CSD)-triggered Ca2+ waves (CSDCWs) in a one-dimensional astrocyte network. This model shows that CASs depend primarily on Ca2+ released from internal stores of astrocytes, and CSDCWs depend mainly on voltage-gated Ca2+ influx. It predicts that voltage-gated Ca2+ influx is able to generate Ca2+ waves during the process of CSD even after depleting internal Ca2+ stores. Furthermore, the model investigates the interactions between CASs and CSDCWs and shows that the pass of CSDCWs suppresses CASs, whereas CASs do not prevent the generation of CSDCWs. This work quantitatively analyzes the generation of astrocytic Ca2+ signals and indicates different mechanisms underlying CSDCWs and non-CSDCWs. Research on the different types of Ca2+ signals might help to understand the ways by which astrocytes participate in information processing in brain functions. 相似文献
947.
N. Aryamanesh Y. Zeng O. Byrne D. C. Hardie A. M. Al-Subhi T. Khan K. H. M. Siddique G. Yan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(2):489-497
Pea weevil, Bruchus pisorum, is one of the limiting factors for field pea (Pisum sativum) cultivation in the world with pesticide application the only available method for its control. Resistance to pea weevil has been found in an accession of Pisum fulvum but transfer of this resistance to cultivated pea (P. sativum) is limited due to a lack of easy-to-use techniques for screening interspecific breeding populations. To address this problem, an interspecific population was created from a cross between cultivated field pea and P. fulvum (resistance source). Quantitative trait locus (QTL) mapping was performed to discover the regions associated with resistance to cotyledon, pod wall/seed coat and pod wall resistance. Three major QTLs, located on linkage groups LG2, LG4 and LG5 were found for cotyledon resistance explaining approximately 80 % of the phenotypic variation. Two major QTLs were found for pod wall/seed coat resistance on LG2 and LG5 explaining approximately 70 % of the phenotypic variation. Co-linearity of QTLs for cotyledon and pod wall/seed coat resistance suggested that the mechanism of resistance for these two traits might act through the same pathways. Only one QTL was found for pod wall resistance on LG7 explaining approximately 9 % of the phenotypic variation. This is the first report on the development of QTL markers to probe Pisum germplasm for pea weevil resistance genes. These flanking markers will be useful in accelerating the process of screening when breeding for pea weevil resistance. 相似文献
948.
Huanhuan Liao Hui He Yuan Chen Fangfa Zeng Jie Huang Li Wu Yong Chen 《Cytotechnology》2014,66(2):229-238
The effects of serial cell passaging on cell spreading, migration, and cell-surface ultrastructures have been less investigated directly. This study evaluated the effects of long-term serial cell passaging (totally 35 passages) on cultured human umbilical vein endothelial cells which were pre-stored at −80 °C as usual. Percentage- and spread area-based spreading assays, measurements of fluorescently labeled actin filaments, migration assay, and measurements of cell-surface roughness were performed and quantitatively analyzed by confocal microscopy or atomic force microscopy. We found that the abilities of cell spreading and migration first increased at early passages and then decreased after passage 15, in agreement with the changes in average length of actin filaments. Recovery from cold storage and effects of cell passaging were potentially responsible for the increases and decreases of the values, respectively. In contrast, the average roughness of cell surfaces (particularly the nucleus-surrounding region) first dropped at early passages and then rose after passage 15, which might be caused by cold storage- and cell passaging-induced endothelial microparticles. Our data will provide important information for understanding serial cell passaging and implies that for pre-stored adherent cells at −80 °C cell passages 5–10 are optimal for in vitro studies. 相似文献
949.
Statistical tests for detecting positive selection by utilizing high-frequency variants 总被引:6,自引:2,他引:6
By comparing the low-, intermediate-, and high-frequency parts of the frequency spectrum, we gain information on the evolutionary forces that influence the pattern of polymorphism in population samples. We emphasize the high-frequency variants on which positive selection and negative (background) selection exhibit different effects. We propose a new estimator of θ (the product of effective population size and neutral mutation rate), θL, which is sensitive to the changes in high-frequency variants. The new θL allows us to revise Fay and Wu's H-test by normalization. To complement the existing statistics (the H-test and Tajima's D-test), we propose a new test, E, which relies on the difference between θL and Watterson's θW. We show that this test is most powerful in detecting the recovery phase after the loss of genetic diversity, which includes the postselective sweep phase. The sensitivities of these tests to (or robustness against) background selection and demographic changes are also considered. Overall, D and H in combination can be most effective in detecting positive selection while being insensitive to other perturbations. We thus propose a joint test, referred to as the DH test. Simulations indicate that DH is indeed sensitive primarily to directional selection and no other driving forces. 相似文献
950.
Characterizing rice lesion mimic mutants and identifying a mutant with broad-spectrum resistance to rice blast and bacterial blight 总被引:34,自引:0,他引:34
Yin Z Chen J Zeng L Goh M Leung H Khush GS Wang GL 《Molecular plant-microbe interactions : MPMI》2000,13(8):869-876
Many plant mutants develop spontaneous lesions that resemble disease symptoms in the absence of pathogen attack. In several pathosystems, lesion mimic mutations have been shown to be involved in programmed cell death, which in some instances leads to enhanced disease resistance to multiple pathogens. We investigated the relationship between spontaneous cell death and disease resistance in rice with nine mutants with a range of lesion mimic phenotypes. All nine mutations are controlled by recessive genes and some of these mutants have stunted growth and other abnormal characteristics. The lesion mimics that appeared on the leaves of these mutants were caused by cell death as measured by trypan blue staining. Activation of six defense-related genes was observed in most of the mutants when the mimic lesions developed. Four mutants exhibited significant enhanced resistance to rice blast. One of the mutants, spl11, confers non-race-specific resistance not only to blast but also to bacterial blight. The level of resistance in the spl11 mutant to the two pathogens correlates with the defense-related gene expression and lesion development on the leaves. The results suggest that some lesion mimic mutations in rice may be involved in disease resistance, and cloning of these genes may provide a clue to developing broad-spectrum resistance to diverse pathogens. 相似文献