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991.
David M. Bates 《Brittonia》1967,19(3):227-236
Reevaluation of the generic limits ofMalvastrum A. Gray requires the transfer of several species. Among these,M. lacteum (Ait.) Garcke andM. subtriflorum (Lag.) Hemsley of Central America and Colombia form a natural alliance differing fromMalvastrum in morphological, cytological, and ecological characteristics and are recognized as a new genus,Kearnemalvastrum. The affinities ofKearnemalvastrum within the tribe Malveae are uncertain. Despite the fact thatK. lacteum andK. subtriflorum occupy similar ecological situations, are fully interfertile, and apparently hybridize to some degree in nature, they do maintain their identity and, therefore, are recognized as species. 相似文献
992.
993.
We do not yet have a good quantitative understanding of how the force-velocity properties of airway smooth muscle interact with the opposing loads of parenchymal tethering and airway wall stiffness to produce the dynamics of bronchoconstriction. We therefore developed a two-dimensional computational model of a dynamically narrowing airway embedded in uniformly elastic lung parenchyma and compared the predictions of the model to published measurements of airway resistance made in rats and rabbits during the development of bronchoconstriction following a bolus injection of methacholine. The model accurately reproduced the experimental time-courses of airway resistance as a function of both lung inflation pressure and tidal volume. The model also showed that the stiffness of the airway wall is similar in rats and rabbits, and significantly greater than that of the lung parenchyma. Our results indicate that the main features of the dynamical nature of bronchoconstriction in vivo can be understood in terms of the classic Hill force-velocity relationship operating against elastic loads provided by the surrounding lung parenchyma and an airway wall that is stiffer than the parenchyma. 相似文献
994.
David Sperandio Vangelis Aktoudianakis Kerim Babaoglu Xiaowu Chen Kristyna Elbel Gregory Chin Britton Corkey Jinfa Du Bob Jiang Tetsuya Kobayashi Richard Mackman Ruben Martinez Hai Yang Jeff Zablocki Saritha Kusam Kim Jordan Heather Webb Jamie G. Bates David G. Breckenridge 《Bioorganic & medicinal chemistry》2019,27(3):457-469
995.
Athanasiou A Smith PA Vakilpour S Kumaran NM Turner AE Bagiokou D Layfield R Ray DE Westwell AD Alexander SP Kendall DA Lobo DN Watson SA Lophatanon A Muir KA Guo DA Bates TE 《Biochemical and biophysical research communications》2007,354(1):50-55
Time-lapse photomicroscopy of human H460 lung cancer cells demonstrated of the transient receptor potential V1 (TRPV1) channel agonists, (E)-capsaicin and resiniferatoxin, and the TRPV1 antagonists, capsazepine, and SB366791, were able to bring about morphological changes characteristic of apoptosis and/or necrosis. Immunoblot analysis identified immunoreactivity for the transient receptor potential V1 (TRPV1) channel in rat brain samples, but not in rat heart mitochondria or in H460 cells. In isolated rat heart mitochondria, all four ligands caused concentration-dependent decreases in oxygen consumption and mitochondrial membrane potential. (E)-Capsaicin and capsazepine evoked concentration-dependent increases and decreases, respectively, in mitochondrial hydrogen peroxide production, whilst resiniferatoxin and SB366791 were without significant effect. These data support the hypothesis that (E)-capsaicin, resiniferatoxin, capsazepine, and SB366791 are all mitochondrial inhibitors, able to activate apoptosis and/or necrosis via non-receptor mediated mechanisms, and also support the use of TRPV1 ligands as anti-cancer agents. 相似文献
996.
Bates LA Sayialel KN Njiraini NW Moss CJ Poole JH Byrne RW 《Current biology : CB》2007,17(22):1938-1942
Animals can benefit from classifying predators or other dangers into categories, tailoring their escape strategies to the type and nature of the risk. Studies of alarm vocalizations have revealed various levels of sophistication in classification. In many taxa, reactions to danger are inflexible, but some species can learn the level of threat presented by the local population of a predator or by specific, recognizable individuals. Some species distinguish several species of predator, giving differentiated warning calls and escape reactions; here, we explore an animal's classification of subgroups within a species. We show that elephants distinguish at least two Kenyan ethnic groups and can identify them by olfactory and color cues independently. In the Amboseli ecosystem, Kenya, young Maasai men demonstrate virility by spearing elephants (Loxodonta africana), but Kamba agriculturalists pose little threat. Elephants showed greater fear when they detected the scent of garments previously worn by Maasai than by Kamba men, and they reacted aggressively to the color associated with Maasai. Elephants are therefore able to classify members of a single species into subgroups that pose different degrees of danger. 相似文献
997.
Nazrul Islam Philip D. Bates K. M. Maria John Hari B. Krishnan Zhanyuan J. Zhang Devanand L. Luthria Savithiry S. Natarajan 《Proteomics》2019,19(7)
To understand the effect of fatty acid desaturase gene (GmFAD3) silencing on perturbation of fatty acid (FA) metabolic pathways, the changes are compared in protein profiling in control and low linolenic acid transgenic soybeans using tandem mass tag based mass spectrometry. Protein profiling of the transgenic line unveiled changes in several key enzymes of FA metabolism. This includes enzymes of lower abundance; fabH, fabF, and thioestrase associated with FA initiation, elongation, and desaturation processes and LOX1_5, ACOX, ACAA1, MFP2 associated with β‐oxidation of α‐linolenic acids pathways. In addition, the GmFAD3 silencing results in a significant reduction in one of the major allergens, Gly m 4 (C6T3L5). These results are important for exploring how plants adjust in their biological processes when certain changes are induced in the genetic makeup. A complete understanding of these processes will aid researchers to alter genes for developing value‐added soybeans. 相似文献
998.
Christian Landles Kirupa Sathasivam Andreas Weiss Ben Woodman Hilary Moffitt Steve Finkbeiner Banghua Sun Juliette Gafni Lisa M. Ellerby Yvon Trottier William G. Richards Alex Osmand Paolo Paganetti Gillian P. Bates 《The Journal of biological chemistry》2010,285(12):8808-8823
Huntingtin proteolysis has been implicated in the molecular pathogenesis of Huntington disease (HD). Despite an intense effort, the identity of the pathogenic smallest N-terminal fragment has not been determined. Using a panel of anti-huntingtin antibodies, we employed an unbiased approach to generate proteolytic cleavage maps of mutant and wild-type huntingtin in the HdhQ150 knock-in mouse model of HD. We identified 14 prominent N-terminal fragments, which, in addition to the full-length protein, can be readily detected in cytoplasmic but not nuclear fractions. These fragments were detected at all ages and are not a consequence of the pathogenic process. We demonstrated that the smallest fragment is an exon 1 huntingtin protein, known to contain a potent nuclear export signal. Prior to the onset of behavioral phenotypes, the exon 1 protein, and possibly other small fragments, accumulate in neuronal nuclei in the form of a detergent insoluble complex, visualized as diffuse granular nuclear staining in tissue sections. This methodology can be used to validate the inhibition of specific proteases as therapeutic targets for HD by pharmacological or genetic approaches. 相似文献
999.
Oligodeoxynucleotide libraries containing randomly incorporated bases are used to generate DNA aptamers by systematic evolution of ligands by exponential enrichment (SELEX). We predicted that combinatorial libraries with alternative base compositions might have innate properties different from the standard library containing equimolar A + C + G + T bases. In particular, we hypothesized that G-rich libraries would contain a higher proportion of quadruplex-forming sequences, which may impart desirable qualities, such as increased nuclease resistance and enhanced cellular uptake. Here, we report on 11 synthetic oligodeoxynucleotide libraries of various base combinations and lengths, with regard to their circular dichroism, stability in serum-containing medium, cellular uptake, protein binding and antiproliferative activity. Unexpectedly, we found that some G-rich libraries (composed of G + T or G + C nucleotides) strongly inhibited cancer cell growth while sparing non-malignant cells. These libraries had spectral features consistent with G-quadruplex formation, were significantly more stable in serum than inactive libraries and showed enhanced cellular uptake. Active libraries generally had strong protein binding, while the pattern of protein binding suggested that G/T and G/C libraries have distinct mechanisms of action. In conclusion, cancer-selective antiproliferative activity may be a general feature of certain G-rich oligodeoxynucleotides and is associated with quadruplex formation, nuclease resistance, efficient cellular uptake and protein binding. 相似文献
1000.
Micha?l Boele van Hensbroek Job C. J. Calis Kamija S. Phiri Raymond Vet Francis Munthali Rob Kraaijenhagen Henk van den Berg Brian Faragher Imelda Bates Malcolm E. Molyneux 《PloS one》2010,5(9)