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81.
82.
Tiziana Vigliarolo Lucrezia Guida Enrico Millo Chiara Fresia Emilia Turco Antonio De Flora Elena Zocchi 《The Journal of biological chemistry》2015,290(21):13042-13052
Abscisic acid (ABA) is a plant hormone involved in the response to environmental stress. Recently, ABA has been shown to be present and active also in mammals, where it stimulates the functional activity of innate immune cells, of mesenchymal and hemopoietic stem cells, and insulin-releasing pancreatic β-cells. LANCL2, the ABA receptor in mammalian cells, is a peripheral membrane protein that localizes at the intracellular side of the plasma membrane. Here we investigated the mechanism enabling ABA transport across the plasmamembrane of human red blood cells (RBC). Both influx and efflux of [3H]ABA occur across intact RBC, as detected by radiometric and chromatographic methods. ABA binds specifically to Band 3 (the RBC anion transporter), as determined by labeling of RBC membranes with biotinylated ABA. Proteoliposomes reconstituted with human purified Band 3 transport [3H]ABA and [35S]sulfate, and ABA transport is sensitive to the specific Band 3 inhibitor 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid. Once inside RBC, ABA stimulates ATP release through the LANCL2-mediated activation of adenylate cyclase. As ATP released from RBC is known to exert a vasodilator response, these results suggest a role for plasma ABA in the regulation of vascular tone. 相似文献
83.
A susceptible strain of Aedes albopictus derived from the Gainesville strain (Florida, USA) was established in our laboratory. The larvicidal efficacies of the neurotoxic insecticides temephos, permethrin and the pure cis and trans-permethrin isomers and the microbial insecticide Bacillus thuringiensis israelensis (Bti) against Ae. albopictus were estimated and compared to a susceptible strain of Aedes aegypti. The larvicidal effect of insect growth regulator pyriproxyfen was also evaluated in both mosquito strains. The median lethal concentration/median emergency inhibition values for Ae. aegypti and Ae. albopictus, respectively, were: temephos, 3.058 and 6.632 ppb, permethrin, 3.143 and 4.933 ppb, cis-permethrin, 4.457 and 10.068 ppb, trans-permethrin, 1.510 and 3.883 ppb, Bti, 0.655 and 0.880 ppb and pyriproxyfen, 0.00774 and 0.01642 ppb. Ae. albopictus was more tolerant than Ae. aegypti to all six larvicides evaluated. The order of susceptibility for Ae. aegypti was pyriproxyfen > Bti > trans-permethrin > temephos > permethrin > cis-permethrin and for Ae. albopictus was pyriproxyfen > Bti > trans-permethrin > permethrin > temephos > cis-permethrin. Because both species can be found together in common urban, suburban and rural breeding sites, the results of this work provide baseline data on the susceptibility of Ae. albopictus to insecticides commonly used for controlling Ae. aegypti in the field. 相似文献
84.
Two bioluminescent enchytraeids, Henlea petushkovi sp. n. and Henlea rodionovae sp. n., are described from the Krasnoyarsk and Irkutsk regions in Eastern Siberia. These large potworms exhibit the typical light-production pattern reported repeatedly in the genus and recently elucidated by Russian researchers in its main biophysical and biochemical aspects. Morphology and DNA indicate that the two species are very closely related, but clearly divergent in the strength of the body wall (thick and opaque in H. petushkovi), structure of the prostomium (in H. rodionovae unprecedentedly wrinkled and mobile), brain shape (almost equilateral in H. petushkovi), size of coelomocytes (60–85 μm in H. petushkovi) and structure of intestinal diverticula (tulip-shaped in H. petushkovi, apple-shaped in H. rodionovae). Limited hybridization seems to occur between them, supported by a single case of conflict between COI and morphology, and a few intermediate morphotypes were noted in greenhouse populations. The new species are phylogenetically distant from all known congeners so far DNA-barcoded, even those that, like them, respond to the diagnosis of the putative subgenus Hepatogaster ?ejka, 1910 (multitubular gut diverticula in VIII, indented brain, dorsal blood vessel from IX, prominent spermathecal glands, and nephridia from 5/6). In fact, our phylogenetic analyses dismiss Hepatogaster as an artificial (polyphyletic) taxon. Issues related to the definition of H. nasuta (Eisen, 1878), H. ochracea (Eisen, 1878) and H. irkutensis Burov, 1929, three species originally described from Siberia, indicate that Henlea taxonomy is still in a state of flux, as regards not only species interrelationships but also species definitions. 相似文献
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86.
Novel water-soluble polymeric photosensitizers based on the natural polymer dextran were synthesized and studied. The modified dextran contained photoactive anthracene (An) chromophores. They were soluble in water with the solubility decreasing with an increase in the number of An moieties bound to the polymeric chain. In aqueous solutions, the macromolecules adopted a compact conformation which resulted in the formation of hydrophobic microdomains. The properties of these domains were characterized with molecular probes such as perylene and pyrazolo-quinoline derivative. The polymer absorbed in the UV/vis region and photosensitized reactions mediated by energy and/or electron transfer from electronically excited An to the molecules of organic compounds solubilized in polymeric microdomains or resided in water. 相似文献
87.
Deepa Alex Emilia Conceição Leong Zai‐Jun Zhang Gloria Tse Ho Yan Shuk‐Han Cheng Chi‐Weng Leong Zhen‐Hua Li Kai‐Heng Lam Shun‐Wan Chan Simon Ming‐Yuen Lee 《Journal of cellular biochemistry》2010,109(2):339-346
Angiogenesis plays an important role in the development of neoplastic diseases such as cancer. Resveratrol and its derivatives exert antiangiogenic effects, but the mechanisms of their actions remain unclear. The aim of this study was to evaluate the antiangiogenic activity of resveratrol and its derivative trans‐3,5,4′‐trimethoxystilbene in vitro using human umbilical vein endothelial cells (HUVECs) and in vivo using transgenic zebrafish, and to clarify their mechanisms of action in zebrafish by gene expression analysis of the vascular endothelial growth factor (VEGF) receptor (VEGFR2/KDR) and cell‐cycle analysis. trans‐3,5,4′‐Trimethoxystilbene showed significantly more potent antiangiogenic activity than that of resveratrol in both assays. In zebrafish, trans‐3,5,4′‐trimethoxystilbene caused intersegmental vessel regression and downregulated VEGFR2 mRNA expression. Trans‐3,5,4′‐trimethoxystilbene also induced G2/M cell‐cycle arrest, most specifically in endothelial cells of zebrafish embryos. We propose that the antiangiogenic and vascular‐targeting activities of trans‐3,5,4′‐trimethoxystilbene result from the downregulation of VEGFR2 expression and cell‐cycle arrest at G2/M phase. J. Cell. Biochem. 109: 339–346, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
88.
Distinct effects of climate warming on populations of silver fir (Abies alba) across Europe 下载免费PDF全文
89.
Dr. Concepción Calvo Ana García de la Paz Victoria Bejar Emilia Quesada Alberto Ramos-Cormenzana 《Current microbiology》1988,17(1):49-53
Thirty-eight strains ofDeleya halophila species were examined for production of phage after mitomycin C induction. Thirty-two of them were able to inhibit growth of some other strains. Phage F9-11, isolated fromD. halophila strain F9-11, showed an isometric head and a noncontractile tail. The effects of salt concentrations variation on the stability and replication of this phage were established. Its replication was possible at a wide range of marine salt concentrations, from 2.5% to 15% (wt/vol). Stability seems to be influenced by osmolarity of medium rather than by NaCl level. The euryhaline character showed by F9-11 phage is evoked as an important factor for the survival of this phage in its environment. 相似文献
90.
Gabriel Minarik Gabriela Repiska Michaela Hyblova Emilia Nagyova Katarina Soltys Jaroslav Budis Frantisek Duris Rastislav Sysak Maria Gerykova Bujalkova Barbora Vlkova-Izrael Orsolya Biro Balint Nagy Tomas Szemes 《PloS one》2015,10(12)