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51.
Fernandes Jackellynne Fernanda Farias Freitas Jailza de Araújo Sandra Alves de Santana Thiago Campos Lobato Rafael Santos Figueiredo Marina Bezerra 《Environmental Biology of Fishes》2022,105(8):1033-1050
Environmental Biology of Fishes - To clarify the reproductive activity of lane snapper, Lutjanus synagris, a total of 359 specimens of lane snapper were collected in partnership with an artisanal... 相似文献
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Barros FW Bandeira PN Lima DJ Meira AS de Farias SS Albuquerque MR dos Santos HS Lemos TL de Morais MO Costa-Lotufo LV Pessoa Cdo Ó 《Bioorganic & medicinal chemistry》2011,19(3):1268-1276
Four derivatives of an α,β-amyrin mixture were synthesized by acylation with appropriate anhydrides. The structures of the compounds were confirmed by means of IR and (1)H and (13)C NMR. The compounds were screened for cytotoxic activity using four human tumor cell lines (HL-60, MDAMB-435, SF-295 and HCT-8) and normal peripheral blood mononuclear cells (PBMC). 3-O-Carboxymaleinate of α,β-amyrin (3a/3b) were found to be the only active compounds of the series (high cytotoxicity), showing IC(50) values ranging from 1.8 to 3μM. In PBMC, 3a/3b were not toxic, suggesting selectivity for tumor cells. To better understand the mechanism of action involved in the cytotoxicity of 3a/3b, HL-60 cells treated with 3a/3b were examined for morphological changes, DNA fragmentation, cell cycle perturbation, externalization of phosphatidylserine and activation of caspases 3/7, with doxorubicin serving as the positive control. The results indicate that the cytotoxicity of 3a/3b involves the induction of cell death by apoptosis. 相似文献
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Plasmepsin (PM) II is one of four enzymes in the food vacuole of Plasmodium falciparum. It has become an attractive target for combating malaria through research regarding its importance in the P. falciparum metabolism and life cycle, making it the target of choice for structure-based drug design. This paper reports the results of hybrid quantum mechanics / molecular mechanics (QM/MM) molecular dynamics (MD) simulations employed to study the details of the interactions established between PM II and N-(3-{(2-benzo[1, 3]dioxol-5-yl-ethyl)[3-(1-methyl-3-oxo-1,3-dihydro-isoindol-2-yl) propionyl]-amino}-1-benzyl-2-(hydroxyl-propyl)-4-benzyloxy-3,5dimethoxy-benzamide (EH58), a well-known potent inhibitor for this enzyme. Electrostatic binding free energy and energy terms decomposition have been computed for PM II complexed with the EH58 inhibitor. The results reveal that there is a strong interaction between Asp34, Val78, Ser79, Tyr192 and Asp214 residues and the EH58 inhibitor. In addition, we have computed the potential of the mean force (PMF) profile in order to assign the protonation state of the two catalytic aspartates in PM II-EH58 complex. The results indicate that the protonation of Asp214 favors a stable active site structure, which is consistent with our electrostatic binding free energy calculation and with previous published works. 相似文献
56.
de Lira FA Farias Mde S de Figueiredo AF Gil Fdos S dos Santos MA Malheiros BV Ferreira JE Pinheiro JC Treu-Filho O Kondo RT 《Journal of molecular modeling》2011,17(7):1621-1624
In a previous article, we used Hartree-Fock (HF) theory to study the piezoelectricity in BaTiO3. In this paper, we applied the Douglas-Kroll-Hess second order scalar relativistic method to investigate the possible piezoelectric
properties in the perovskite YFeO3 structure, which has not yet been studied experimentally. The 30s20p13d and 31s21p17d Gaussian basis sets for the Fe (5D) and Y (2D) atoms, respectively, were built with the Generator Coordinate HF method. After contraction to [13s7p5d] and [13s8p7d],
in combination with the 20s14p/6s4p basis set for the O (3P) atom from literature, they had their quality evaluated using calculations of the total and the orbital energies for the
2FeO+1 and 1YO+1 fragments. The dipole moment, the total energy, and the total atomic charges in YFeO3 in Cs space group were calculated. The results and the analysis lead us to believe that the perovskite YFeO3 does not present piezoelectric properties. 相似文献
57.
Molecular Ecology Resources Primer Development Consortium Agata K Alasaad S Almeida-Val VM Alvarez-Dios JA Barbisan F Beadell JS Beltrán JF Benítez M Bino G Bleay C Bloor P Bohlmann J Booth W Boscari E Caccone A Campos T Carvalho BM Climaco GT Clobert J Congiu L Cowger C Dias G Doadrio I Farias IP Ferrand N Freitas PD Fusco G Galetti PM Gallardo-Escárate C Gaunt MW Ocampo ZG Gonçalves H Gonzalez EG Haye P Honnay O Hyseni C Jacquemyn H Jowers MJ Kakezawa A Kawaguchi E Keeling CI Kwan YS 《Molecular ecology resources》2011,11(3):586-589
This article documents the addition of 238 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Alytes dickhilleni, Arapaima gigas, Austropotamobius italicus, Blumeria graminis f. sp. tritici, Cobitis lutheri, Dendroctonus ponderosae, Glossina morsitans morsitans, Haplophilus subterraneus, Kirengeshoma palmata, Lysimachia japonica, Macrolophus pygmaeus, Microtus cabrerae, Mytilus galloprovincialis, Pallisentis (Neosentis) celatus, Pulmonaria officinalis, Salminus franciscanus, Thais chocolata and Zootoca vivipara. These loci were cross-tested on the following species: Acanthina monodon, Alytes cisternasii, Alytes maurus, Alytes muletensis, Alytes obstetricans almogavarii, Alytes obstetricans boscai, Alytes obstetricans obstetricans, Alytes obstetricans pertinax, Cambarellus montezumae, Cambarellus zempoalensis, Chorus giganteus, Cobitis tetralineata, Glossina fuscipes fuscipes, Glossina pallidipes, Lysimachia japonica var. japonica, Lysimachia japonica var. minutissima, Orconectes virilis, Pacifastacus leniusculus, Procambarus clarkii, Salminus brasiliensis and Salminus hilarii. 相似文献
58.
Antonio Paulo Nassar Junior Alberto Queiroz Farias Luiz Augusto Carneiro d’ Albuquerque Flair José Carrilho Luiz Marcelo Sá Malbouisson 《PloS one》2014,9(9)
Background
Hepatorenal syndrome (HRS) is a severe and progressive functional renal failure occurring in patients with cirrhosis and ascites. Terlipressin is recognized as an effective treatment of HRS, but it is expensive and not widely available. Norepinephrine could be an effective alternative. This systematic review and meta-analysis aimed to evaluate the efficacy and safety of norepinephrine compared to terlipressin in the management of HRS.Methods
We searched the Medline, Embase, Scopus, CENTRAL, Lilacs and Scielo databases for randomized trials of norepinephrine and terlipressin in the treatment of HRS up to January 2014. Two reviewers collected data and assessed the outcomes and risk of bias. The primary outcome was the reversal of HRS. Secondary outcomes were mortality, recurrence of HRS and adverse events.Results
Four studies comprising 154 patients were included. All trials were considered to be at overall high risk of bias. There was no difference in the reversal of HRS (RR = 0.97, 95% CI = 0.76 to 1.23), mortality at 30 days (RR = 0.89, 95% CI = 0.68 to 1.17) and recurrence of HRS (RR = 0.72; 95% CI = 0.36 to 1.45) between norepinephrine and terlipressin. Adverse events were less common with norepinephrine (RR = 0.36, 95% CI = 0.15 to 0.83).Conclusions
Norepinephrine seems to be an attractive alternative to terlipressin in the treatment of HRS and is associated with less adverse events. However, these findings are based on data extracted from only four small studies. 相似文献59.
Gorman MW Farias M Richmond KN Tune JD Feigl EO 《American journal of physiology. Heart and circulatory physiology》2005,288(4):H1937-H1942
It has been proposed that alpha-adrenoceptor vasoconstriction in coronary resistance vessels results not from alpha-adrenoceptors on coronary smooth muscle but from alpha-adrenoceptors on cardiac myocytes that stimulate endothelin (ET) release. The present experiments tested the hypothesis that the alpha-adrenoceptor-mediated coronary vasoconstriction that normally occurs during exercise is due to endothelin. In conscious dogs (n = 10), the endothelin ET(A)/ET(B) receptor antagonist tezosentan (1 mg/kg iv) increased coronary venous oxygen tension at rest but not during treadmill exercise. This result indicates that basal endothelin levels produce a coronary vasoconstriction at rest that is not observed during the coronary vasodilation during exercise. In contrast, the alpha-adrenoceptor antagonist phentolamine increased coronary venous oxygen tension during exercise but not at rest. The difference between the endothelin blockade and alpha-adrenoceptor blockade results indicates that alpha-adrenoceptor coronary vasoconstriction during exercise is not due to endothelin. However, in anesthetized dogs, bolus intracoronary injections of the alpha-adrenoceptor agonist phenylephrine produced reductions in coronary blood flow that were partially antagonized by endothelin receptor blockade with tezosentan. These results are best explained if alpha-adrenoceptor-induced endothelin release requires high pharmacological concentrations of catecholamines that are not reached during exercise. 相似文献
60.
Cantanhede AM Da Silva VM Farias IP Hrbek T Lazzarini SM Alves-Gomes J 《Molecular ecology》2005,14(2):401-413
We used mitochondrial DNA control region sequences to examine phylogeography and population differentiation of the endangered Amazonian manatee Trichechus inunguis. We observe lack of molecular differentiation among localities and we find weak association between geographical and genetic distances. However, nested clade analysis supports restricted gene flow and/or dispersal with some long-distance dispersal. Although this species has a history of extensive hunting, genetic diversity and effective population sizes are relatively high when compared to the West Indian manatee Trichechus manatus. Patterns of mtDNA haplotype diversity in T. inunguis suggest a genetic disequilibrium most likely explained by demographic expansion resulting from secession of hunting and enforcement of conservation and protective measures. Phylogenetic analysis of T. manatus and T. inunguis haplotypes suggests that T. inunguis is nested within T. manatus, effectively making T. manatus a paraphyletic entity. Paraphyly of T. manatus and recent divergence times of T. inunguis and the three main T. manatus lineages suggest a possible need for a taxonomic re-evaluation of the western Atlantic Trichechus. 相似文献