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141.
Ling Wang Yu Wang Yiguang Tian Jinling Shang Xiaoou Sun Hongzhuan Chen Hao Wang Wen Tan 《Bioorganic & medicinal chemistry》2017,25(1):360-371
A series of novel chalcone-rivastigmine hybrids were designed, synthesized, and tested in vitro for their ability to inhibit human acetylcholinesterase and butyrylcholinesterase. Most of the target compounds showed hBChE selective activity in the micro- and submicromolar ranges. The most potent compound 3 exhibited comparable IC50 to the commercially available drug (rivastigmine). To better understand their structure activity relationships (SAR) and mechanisms of enzyme-inhibitor interactions, kinetic and molecular modeling studies including molecular docking and molecular dynamics (MD) simulations were carried out. Furthermore, compound 3 blocks the formation of reactive oxygen species (ROS) in SH-SY5Y cells and shows the required druggability and low cytotoxicity, suggesting this hybrid is a promising multifunctional drug candidate for Alzheimer’s disease (AD) treatment. 相似文献
142.
R. H. Douglas 《Journal of fish biology》1996,49(3):532-536
Three goldfish were trained to search for food buried 20 cm from a perspex tower. In the absence of food, all fish still searched in the correct location, revealing that fish can use a landmark to locate food. Halving either the width or height of the landmark resulted in searches significantly closer to the tower, suggesting that fish determined their position relative to the landmark using its horizontal and vertical visual angles. 相似文献
143.
Zhongcheng Cao Jie Yang Rui Xu Qin Song Xiaoyu Zhang Hongyan Liu Xiaoming Qiang Yan Li Zhenghuai Tan Yong Deng 《Bioorganic & medicinal chemistry》2018,26(5):1102-1115
A series of 4′-OH-flurbiprofen-chalcone hybrids were designed, synthesized and evaluated as potential multifunctional agents for the treatment of Alzheimer’s disease. The biological screening results indicated that most of these hybrids exhibited good multifunctional activities. Among them, compounds 7k and 7m demonstrated the best inhibitory effects on self-induced Aβ1–42 aggregation (60.0% and 78.2%, respectively) and Cu2+-induced Aβ1–42 aggregation (52.4% and 95.0%, respectively). Moreover, these two representative compounds also exhibited good antioxidant activities, MAO inhibitions, biometal chelating abilities and anti-neuroinflammatory activities in vitro. Furthermore, compound 7m displayed appropriate blood-brain barrier permeability. These multifunctional properties highlight compound 7k and 7m as promising candidates for further development of multi-functional drugs against AD. 相似文献
144.
In experiments with 5x5 diallel cross of tomato cv. Smrické contents of individual chlorophylls (Chl) and carotenoids (Car), Chl fluorescence kinetic parameters (Fv/Fm, qp, qN and II), activities of photosystem 2 and of the whole electron transport chain (Hill reaction) were compared during plant ontogeny with the aim to detect genetically determined differences among genotypes. The differences in Chl fluorescence kinetic parameters and Hill reaction activities were more affected by leaf development than by plant genotype, although the differences between reciprocal crosses were found in the former ones. Some additive genetic effects may participate in the genetic determination of qN. Statistically significant non-additive genetic effects in inheritance of the total Chl content were found. Detailed pigment analysis revealed additivity together with differences between reciprocal crosses in individual Car and Chl. The highest general combining ability was found for the parental line AM. 相似文献
145.
H. Hashimoto H. Toyohara Y. Yokoyama † M. Sakaguchi K. Ozato ‡ Y. Wakamatsu ‡ 《Journal of fish biology》1997,50(1):201-207
The culture medium supplemented with carp serum and fetal bovine serum (FBS) promoted cell growth significantly and induced morphological change of goldfish fin cells in early passage as compared to the medium containing FBS alone. However, these effects were not observed in RBCF-1, a cell line established from the goldfish fin. The sensitivity of the cells in early passage to carp serum suggests the following possibilities: (1) cells in early passage retain the ability to respond to growth-promoting factors specifically included in carp serum; and (2) this ability is lost during the process of long-term culture and/or long-term culture in FBS eliminates cell groups showing high dependency of cell growth on carp serum. 相似文献
146.
S. W. Hussain W. M. Williams 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):678-690
Trifolium ambiguum M. Bieb and T. repens L. are taxonomically related but very difficult to cross. The rare hybrids so far reported between these two species were
obtained only by embryo culture. This difficulty has been overcome in the present research by the creation of a “fertile bridge”
between T. ambiguum and T. repens. Characters of interest can now be transferred from T. ambiguum to T. repens by using this “fertile bridge” without the use of sophisticated techniques. An array of backcross progenies was generated
from crosses between a T. ambiguum×T. repens F1 hybrid (8x H-435) and its parental species. The 8x hybrid was cross-fertile only with T. repens and resulted in 145 seeds from 1578 reciprocal crosses. Eleven of nineteen initially grown BC1F1 plants were all hexaploid with an average pollen stainability of 41.6%. A high frequency of multivalents at metaphase-I indicated
that both autosyndetic and allosyndetic pairing occurred. Backcrosses of 6x BC1F1 plants to T. repens resulted in 5x BC2F1 plants with an average pollen stainability of 59.3%. On the other hand, 6x BC1F1×6x T. ambiguum crosses did not produce any seed and only two pentaploid plants were obtained from 6x BC1F1×4x T. ambiguum crosses. The difficulty encountered in generating 6x backcross progeny with 6x T. ambiguum was overcome by intercrossing the 6x BC1F1 plants and producing 6x BC1F2 plants with an average pollen stainability of 65.8%. One of these 6x BC1F2 plants was cross-compatible as a female with 6x T. ambiguum and resulted in CBC2 plants that were all cross-compatible with 6x T. ambiguum. The 6x BC1F2 plants are likely to be superior to 6x BC1F1 progeny, as they have exhibited better expression of the combined rhizomatous and stoloniferous growth habit, improved fertility,
more frequent nodal rooting and heavier nodulation. Consequently, the 6x BC1F2 plants can either be used directly in the selection programme or as a “fertile bridge” between the two parental species.
The present work has resulted in the development of a series of fertile hybrids by the manipulation of chromosome numbers,
combining the agronomic characteristics of the parent species in varying genome balances and at a range of ploidy levels.
It is concluded that the initial sterility of the primary interspecific hybrids need not be a barrier to successful inter-breeding.
Received: 2 August 1996 / Accepted: 4 April 1997 相似文献
147.
C. Conicella G. Genualdo R. Lucia K. S. Ramulu T. Cardi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):609-617
Somatic hybridization between Solanum commersonii and S. tuberosum resulted in the production of male-sterile hybrid plants, except for one fully male-fertile hybrid. The male-sterile hybrids
exhibited a“pollen-less” phenotype, with rare pollen grains which were abnormal in shape and exine sculpture. Microsporogenesis
and tapetal development were investigated both in male-sterile and male-fertile somatic hybrids to assess the cytological
events that were involved in male sterility. The pattern of male sterility was complex, arising through mechanisms expressed
at both sporophytic and gametophytic levels. Various abnormalities occurred first in the tapetum, and later during meiosis-II
and cytokinesis. These caused the degeneration of the sporads and of the microspores when they were released. In the male-fertile
hybrid, normal development of the tapetum and pollen mother cells was restored. The hypothesis that tapetal breakdown, meiosis-II
and cytokinesis defects are related to each other, and depend on nuclear-mitochondrial interactions, is discussed. Because
of the formation of multivalent chromosome configurations, it is likely that gene exchange between S. commersonii and S. tuberosum can occur in somatic hybrids, offering potential perspectives for the introgression of useful traits from S. commersonii into S. tuberosum.
Received: 10 December 1996/Accepted: 21 March 1997 相似文献
148.
M. J. Alves ‡ M. J. Collares-Pereira T. E. Dowling † M. M. Coelho 《Journal of fish biology》2002,60(3):649-662
Squalius alburnoides is a complex of minnows common to the Iberian Peninsula, consisting of two distinct forms. The most common form is comprised of diploid and polyploid asexual hybrids heterozygous for several diagnostic allozyme loci contributed by Squalius pyrenaicus or Squalius carolitertii and a missing ancestor. The other form is diploid and homozygous for the allele contributed by the missing ancestor at these same loci. Present results from analyses of sex ratio and cytochrome b sequences are not consistent with the evolutionary distinctiveness of this non-hybrid form and suggest that it represents an all-male lineage imbedded within an almost all-female complex. This all-male lineage allowed preservation of the ancestral paternal nuclear genome after the paternal ancestor became extinct in all or most drainages, withimportant evolutionary implications. 相似文献
149.
David Berrigan Ary A. Hoffmann 《Biological journal of the Linnean Society. Linnean Society of London》1998,64(4):449-462
Associations between traits may differ at the interspecific and intraspecific levels, making it difficult to predict long term evolutionary constraints. In this study we used replicate hybrid lines generated from crosses between Drosophila serrata and D. birchii to investigate correlations between measures of heat resistance and acclimation responses. Within each species, knockdown heat resistance was uncorrelated with heat resistance as measured by mortality. In contrast, D. serrata was more resistant than D. birchii for both measures of heat resistance. Thus, inter- and intraspecific correlations between measures of heat resistance differ. In the hybrids, there was no evidence for a correlation between knockdown time and heat induced mortality. Hybrid data did suggest a trade-off between acclimation for knockdown heat resistance and heat resistance as measured by mortality. We argue that hybrids between species are a potentially useful tool for studying traits such as acclimation responses that show litde genetic variation within species. 相似文献
150.
Roegneria grandis was hybridized withR. ciliaris var.japonensis (2n = 28, SSYY),Elymus caninus (2n = 28, SSHH), andPseudoroegneria spicata (2n = 28, SSSS). Chromosome pairing was studied in parents and hybrids. It is concluded from this study that: (i)R. grandis is an allotetraploid species and contains the basic genomes S and Y: (ii) a certain degree of homoeology exists between the S and Y genomes of the species studied. 相似文献