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81.
The side-chain double bonds of bacterial poly[3-hydroxyalkanoate-co-3-hydroxyalkenoate] (PHAE, 1) were transformed into thioether bonds (derivative 2) via the radical addition reaction of 11-mercapto-1-undecanol. The terminal hydroxy functionalities of derivative 2 were subsequently esterified with cinnamic acid (derivative 3), sulfatized with ClSO(3)H (derivative 4), or coupled with tert-butyldimethylsilyl-protected coumaric acid, to give, after deprotection with tetrabutylammonium fluoride (derivative 5) followed by sulfatization, p-(sulfooxy) cinnamic acid- (zosteric acid) labeled PHAE (derivative 6). The reactions proceeded with good yields and little side reactions, which was confirmed with (1)H NMR and GPC experiments. These functionalized polyesters are currently investigated as environmentally friendly coatings to protect surfaces from biofouling. 相似文献
82.
Reem A. Alajmi Dina M. Metwally Manal F. El-Khadragy Hany M. Yehia Saeed El-Ashram Zainab Almusawi Muhammad Amjad Bashir Noura J. Alotaibi Rewaida Abdel-Gaber 《Saudi Journal of Biological Sciences》2021,28(4):2613-2617
The taxonomy of the order Phthiraptera is unstable and still problematic to researchers. Most of the current taxon classifications are mainly based on morphological features. Campanulotes bidentatus belongs to the chewing lice of the Philopteridae family that mostly parasitic on birds. There is a lack of sequence data and phylogenetic analyses on the family Philopteridae. In the current study, C. bidentatus was collected from the domestic pigeon Columba livia and identified morphologically and molecularly based on the mitochondrial cytochrome c oxidase subunit 1 gene (COI). The infection rate of the Campanulotes genus was approximately 58.82% in this study. Phylogenetic analysis based on the mt COI gene was informative for members of Philopteridae and the group taxon genera formed distinct clades. Future studies were recommended using the 16s rRNA to enhance the tree topology and obtain clear differentiation between genera. 相似文献
83.
Mariem Ben-Abdallah Vincent Bondet Fabien Fauchereau Pierre Béguin Hany Goubran-Botros Cécile Pagan Thomas Bourgeron Jacques Bellalou 《Protein expression and purification》2011,75(1):114-118
N-acetyl serotonin methyl transferase (ASMT) is the last enzyme in the melatonin synthesis pathway. Evidence linking autism-related disorders with disorders of melatonin metabolism, and, more specifically, with mutations of the gene encoding ASMT, prompted us to investigate the properties and localization of this enzyme. As a first step, we undertook to overproduce the protein in a recombinant host. Early attempts to produce ASMT in recombinant Escherichia coli yielded only insoluble and heavily degraded material. However, recombinant ASMT (rASMT) could be produced in soluble, active form and purified in milligram amounts when the gene was cloned and expressed in Leishmania tarentolae. 相似文献
84.
Comparative studies of the effects of two compounds, tebufenozide (an ecdysone agonist) and lufenuron (an insect growth regulator
inhibiting chitin synthesis), were conducted on Spodoptera littoralis (Boisduval, 1833). The compounds, orally administered, caused larval mortality proportional to the concentrations in the
food source. Tebufenozide initiated precocious molting, and lufenuron, and inhibited chitin synthesis. In both cases, larvae
were unable to complete the molting process and died in the old larval cuticle. Larvae contaminated by sublethal doses completed
their development to adulthood. Lufenuron is more active than is tebufenozide. LD-50 for lufenuron is 0.0001ppm and for tebufenozide
0.001ppm. Topical application of the test compounds to eggs caused dose- and agedependent inhibition of embryonic development.
Application of tebufenozide in the second half of embryogenesis caused precocious molting of eclosed larvae of the 1st instar. Some morphological changes in the process of larval-pupal transformation were also observed. Tested compounds also
reduced reproduction in adult individuals that had been treated by the tested compounds in the larval stage. 相似文献
85.
Priya Date Hany K. M. Dweck Marcus C. Stensmyr Jodi Shann Bill S. Hansson Stephanie M. Rollmann 《PloS one》2013,8(7)
Divergence in host adaptive traits has been well studied from an ecological and evolutionary perspective, but identification of the proximate mechanisms underlying such divergence is less well understood. Behavioral preferences for host plants are often mediated by olfaction and shifts in preference may be accompanied by changes in the olfactory system. In this study, we examine the evolution of host plant preferences in cactophilic Drosophila mojavensis that feeds and breeds on different cacti throughout its range. We show divergence in electrophysiological responses and olfactory behavior among populations with host plant shifts. Specifically, significant divergence was observed in the Mojave Desert population that specializes on barrel cactus. Differences were observed in electrophysiological responses of the olfactory organs and in behavioral responses to barrel cactus volatiles. Together our results suggest that the peripheral nervous system has changed in response to different ecological environments and that these changes likely contribute to divergence among D. mojavensis populations. 相似文献
86.
Mohamed Elagawany Mohamed A. Ibrahim Hany Emary Ali Ahmed A.Sh. El-Etrawy Adel Ghiaty Zakaria K. Abdel-Samii Said A. El-Feky Jürgen Bajorath 《Bioorganic & medicinal chemistry letters》2013,23(7):2007-2013
The design and synthesis of pyridazinone and phthalazinone derivatives are described. Newly synthesized compounds were tested on a panel of four kinases in order to evaluate their activity and potential selectivity. In addition, the promising compounds were tested on four cancer cell lines to examine cytotoxic effects. The compounds inhibited DYRK1A and GSK3 with different activity. SAR analysis and docking calculations were carried out to aid in the interpretation of the results. Taken together, our findings suggest that pyridazinone and phthalazinone scaffolds are interesting starting points for design of potent GSK3 and DYRK1A inhibitors. 相似文献
87.
88.
Dias MP Granadeiro JP Phillips RA Alonso H Catry P 《Proceedings. Biological sciences / The Royal Society》2011,278(1713):1786-1793
There is growing evidence that migratory species are particularly vulnerable to rapid environmental changes arising from human activity. Species are expected to vary in their capacity to respond to these changes: long-distance migrants and those lacking variability in migratory traits are probably at considerable disadvantage. The few studies that have assessed the degree of plasticity in behaviour of marine animals suggest that fidelity to non-breeding destinations is usually high. In the present study, we evaluated individual flexibility in migration strategy of a highly pelagic seabird, the Cory's shearwater Calonectris diomedea. Geolocation data from 72 different migrations, including 14 birds that were tracked for more than one non-breeding season, showed a remarkable capacity to change winter destinations between years. Although some birds exhibited high site fidelity, others shifted from the South to North Atlantic, from the western to eastern South Atlantic, and from the Atlantic to Indian Ocean. Individuals also showed flexibility in stopover behaviour and migratory schedule. Although their K-selected life-history strategy has the disadvantage that the chances of microevolution are slight if circumstances alter rapidly, these results suggest that Cory's shearwaters may be in a better position than many other long-distance migrants to face the consequences of a changing environment. 相似文献
89.
Nanotubes impregnated human olfactory bulb neural stem cells promote neuronal differentiation in Trimethyltin‐induced neurodegeneration rat model 下载免费PDF全文
90.
Human olfactory bulb neural stem cells mitigate movement disorders in a rat model of Parkinson's disease 下载免费PDF全文