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131.
Luiz A. R. Freitas Lilian V. S. Carvalho Jonathan L. M. Fontes Cassiana S. Souza Reginaldo B. Santos Jr. Lara T. Cardoso Claudio P. Figueira Milton S. Fonseca Neto Rafael C. M. F. Dias Manuela S. Solc Marilda S. Gonalves Setondji C. M. A. Yahouedehou Ceuci L. X. Nunes Geraldo G. S. Oliveira Washington L. C. dosSantos 《Journal of cellular and molecular medicine》2021,25(21):10318
132.
Tenreiro S Nunes PA Viegas CA Neves MS Teixeira MC Cabral MG Sá-Correia I 《Biochemical and biophysical research communications》2002,292(3):741-748
We report results on the functional analysis of Saccharomyces cerevisiae ORF YNL065w, predicted to code for a protein belonging to the poorly characterized major facilitator superfamily (MFS) of transporters that are involved in multidrug resistance (MDR). YNL065w is important for a moderate increase of yeast tolerance to ketoconazole and to the cationic dye crystal violet; it protects the cell against short-chain monocarboxylic acids (C(2)-C(6)), but not against highly liposoluble acids such as octanoic acid or the phenoxyacetic-acid herbicides 2,4-D and MCPA; it is also a determinant of resistance to the antiarrhytmic and antimalarial drug quinidine. The encoding ORF was, thus, denominated the AQR1 gene. Results obtained using an AQR1-lacZ fusion indicate that gene expression is very low and it is not stimulated under weak acid stress. The encoded putative transporter was localized in the plasma membrane by fluorescence microscopy observation of the overproduced Aqr1-GFP fusion protein distribution. 相似文献
133.
Gomes MB Cobas RA Nunes E Nery M Castro-Faria-Neto HC Tibiriçá E 《Prostaglandins & other lipid mediators》2008,87(1-4):42-46
Plasma activity of the platelet-activating factor acetylhydrolase (PAF-AH) plays an important role in inflammation and atherosclerotic process in chronic diseases. We aimed to evaluate the levels of PAF-AH activity and their association with the metabolic profile and chronic complications in patients with type 1 diabetes. The study included 118 outpatients (54 males) aged 27.1+/-11.3 years with disease duration of 12.3+/-8.5 years with (n=38) or without (n=80) diabetes complications and 96 control subjects (48 males) matched for age, gender, body mass index and smoking habits. The serum levels of PAF-AH activity were higher in patients either with or without chronic complications (16+/-5.3 and 14+/-5.4 nmol/(min mL), respectively) than in controls (13+/-5.1 nmol/(min mL), P=0.02). In the total population, PAF-AH activity was correlated with age, HDL-cholesterol, total cholesterol and LDL-cholesterol. In patients, PAF-AH activity was correlated with age, HbA1c, uric acid, HDL-cholesterol, cholesterol, LDL-cholesterol, cholesterol/HDL-cholesterol ratio and the LDL-cholesterol/HDL-cholesterol ratio. It is concluded that PAF-AH plasma activity could be a novel candidate for low-grade inflammatory marker in patients with type 1 diabetes. 相似文献
134.
Silva JR van den Hurk R Costa SH Andrade ER Nunes AP Ferreira FV Lôbo RN Figueiredo JR 《Animal reproduction science》2004,81(3-4):273-286
The development of culture systems to support the initiation of growth of primordial follicles is important to the study of the factors that control the earliest stages of folliculogenesis. We investigated the effectiveness of five culture media, two supplements and three culture periods on the survival and growth of goat primordial follicles after culturing ovarian cortex. The media were based on minimal essential minimum (MEM) and coconut water solution (CWS) added in the proportion of 0, 25, 50, 75 or 100%. The two supplements were none versus supplemented with insulin-transferrin-selenium, pyruvate, glutamine, hypoxanthine, and BSA. Pieces of goat ovarian cortex were cultured in the media for 1, 3 or 5 days and representative samples were evaluated at day 0 as non-cultured controls. The replicates were the two ovaries of five mixed breed goats. The number of primordial, intermediate, primary and secondary follicles at each period of culture and the number of degenerated follicles were evaluated. Mitotic activity of granulosa cells was studied by immunolocalization of proliferating cell nuclear antigen (PCNA). The number of follicles in each stage and degenerated follicles were statistically analyzed by ANOVA using a factorial design and the significance of differences assessed using Tukey test. Chi-square test was used to compare the percentage of follicles with PCNA positive granulosa cells. As the culture period progressed, the number of primordial follicles fell and there was a significant increase in the number of primary follicles. The fall in the number of primordial follicles was particularly marked after 1 day culture. No effect of media on the number of primordial and primary follicles was observed after culture, but MEM as well as supplements increased the number of intermediate follicles. Follicular degeneration was kept at the same level after culture in the media tested, except for pure CWS that increased the number of degenerated follicles. In contrast, addition of supplements to culture media reduced follicular degeneration. In non-cultured tissue, PCNA was expressed in granulosa cells of 31.6% of the growing follicles. This percentage had not significantly changed after 5 days culture in the various media, indicating the maintenance of proliferation activity of granulosa cells during culture. In conclusion, it is shown that goat primordial follicles may be successfully activated after in vitro culture in all media tested. However, when pure CWS is used the follicular degeneration is enhanced, but the addition of supplements to culture media decrease follicular degeneration. 相似文献
135.
Lopes PA Viegas-Cresp AM Nunes AC Pinheiro T Marques C Santos MC Mathias Mde L 《Biological trace element research》2002,85(3):227-239
The influence of age, gender and sexual activity on both hepatic levels of some trace elements (Fe, Cu, Zn, Mn, Se) and the
activities of glutathione-S-transferase (GST) and superoxide dismutase (SOD) was investigated in Wood mice (Apodemus sylvaticus) and Algerian mice (Mus spretus). Animals were taken from a riverside community of an unpolluted area of central Portugal. Adult A. sylvaticus presented the highest hepatic mean concentrations of Cu and Mn, whereas adult M. spretus had the highest Fe concentration in the liver. Moreover, an influence of age on the contents of Fe, Zn, and Mn has been observed
in A. sylvaticus, whereas in M. spretus an influence of gender and sexual activity was only detected on Zn levels. In contrast, enzyme activities were not influenced
by the studied variables, despite a tendency for an increase in SOD activity in sexually active M. spretus. GST activity was species dependent, whereas SOD activity was similar between species. These findings were analyzed regarding
the relationship of both essential trace elements and the two antioxidant enzymes with physiological and metabolic pathways
related to life cycles in the two species of mice. Results enhanced the understanding of A. sylvaticus and M. spretus as biological models, allowing their future use as bioindicators of environmental toxicity. 相似文献
136.
137.
Igor C. S. Cruz Miguel Loiola Tiago Albuquerque Rodrigo Reis José de Anchieta C. C. Nunes James D. Reimer Masaru Mizuyama Ruy K. P. Kikuchi Joel C. Creed 《PloS one》2015,10(1)
Consequences of reef phase shifts on fish communities remain poorly understood. Studies on the causes, effects and consequences of phase shifts on reef fish communities have only been considered for coral-to-macroalgae shifts. Therefore, there is a large information gap regarding the consequences of novel phase shifts and how these kinds of phase shifts impact on fish assemblages. This study aimed to compare the fish assemblages on reefs under normal conditions (relatively high cover of corals) to those which have shifted to a dominance of the zoantharian Palythoa cf. variabilis on coral reefs in Todos os Santos Bay (TSB), Brazilian eastern coast. We examined eight reefs, where we estimated cover of corals and P. cf. variabilis and coral reef fish richness, abundance and body size. Fish richness differed significantly between normal reefs (48 species) and phase-shift reefs (38 species), a 20% reduction in species. However there was no difference in fish abundance between normal and phase shift reefs. One fish species, Chaetodon striatus, was significantly less abundant on normal reefs. The differences in fish assemblages between different reef phases was due to differences in trophic groups of fish; on normal reefs carnivorous fishes were more abundant, while on phase shift reefs mobile invertivores dominated. 相似文献
138.
Robert J. Wickham Jinwoo Park Eric J. Nunes Nii A. Addy 《Journal of visualized experiments : JoVE》2015,(102)
Rapid, phasic dopamine (DA) release in the mammalian brain plays a critical role in reward processing, reinforcement learning, and motivational control. Fast scan cyclic voltammetry (FSCV) is an electrochemical technique with high spatial and temporal (sub-second) resolution that has been utilized to examine phasic DA release in several types of preparations. In vitro experiments in single-cells and brain slices and in vivo experiments in anesthetized rodents have been used to identify mechanisms that mediate dopamine release and uptake under normal conditions and in disease models. Over the last 20 years, in vivo FSCV experiments in awake, freely moving rodents have also provided insight of dopaminergic mechanisms in reward processing and reward learning. One major advantage of the awake, freely moving preparation is the ability to examine rapid DA fluctuations that are time-locked to specific behavioral events or to reward or cue presentation. However, one limitation of combined behavior and voltammetry experiments is the difficulty of dissociating DA effects that are specific to primary rewarding or aversive stimuli from co-occurring DA fluctuations that mediate reward-directed or other motor behaviors. Here, we describe a combined method using in vivo FSCV and intra-oral infusion in an awake rat to directly investigate DA responses to oral tastants. In these experiments, oral tastants are infused directly to the palate of the rat – bypassing reward-directed behavior and voluntary drinking behavior – allowing for direct examination of DA responses to tastant stimuli. 相似文献
139.
Rodrigo Nunes Rodrigues-da-Silva Jo?o Hermínio Martins da Silva Balwan Singh Jianlin Jiang Esmeralda V. S. Meyer Fátima Santos Dalma Maria Banic Alberto Moreno Mary R. Galinski Joseli Oliveira-Ferreira Josué da Costa Lima-Junior 《PloS one》2016,11(1)
Synthetic peptide vaccines provide the advantages of safety, stability and low cost. The success of this approach is highly dependent on efficient epitope identification and synthetic strategies for efficacious delivery. In malaria, the Merozoite Surface Protein-9 of Plasmodium vivax (PvMSP9) has been considered a vaccine candidate based on the evidence that specific antibodies were able to inhibit merozoite invasion and recombinant proteins were highly immunogenic in mice and humans. However the identities of linear B-cell epitopes within PvMSP9 as targets of functional antibodies remain undefined. We used several publicly-available algorithms for in silico analyses and prediction of relevant B cell epitopes within PMSP9. We show that the tandem repeat sequence EAAPENAEPVHENA (PvMSP9E795-A808) present at the C-terminal region is a promising target for antibodies, given its high combined score to be a linear epitope and located in a putative intrinsically unstructured region of the native protein. To confirm the predictive value of the computational approach, plasma samples from 545 naturally exposed individuals were screened for IgG reactivity against the recombinant PvMSP9-RIRII729-972 and a synthetic peptide representing the predicted B cell epitope PvMSP9E795-A808. 316 individuals (58%) were responders to the full repetitive region PvMSP9-RIRII, of which 177 (56%) also presented total IgG reactivity against the synthetic peptide, confirming it validity as a B cell epitope. The reactivity indexes of anti-PvMSP9-RIRII and anti-PvMSP9E795-A808 antibodies were correlated. Interestingly, a potential role in the acquisition of protective immunity was associated with the linear epitope, since the IgG1 subclass against PvMSP9E795-A808 was the prevalent subclass and this directly correlated with time elapsed since the last malaria episode; however this was not observed in the antibody responses against the full PvMSP9-RIRII. In conclusion, our findings identified and experimentally confirmed the potential of PvMSP9E795-A808 as an immunogenic linear B cell epitope within the P. vivax malaria vaccine candidate PvMSP9 and support its inclusion in future subunit vaccines. 相似文献
140.
Aristóteles Philippe Nunes Queiroz Maria Lúcia Góes Araújo Nigel E. Hussey Rosângela P. T. Lessa 《Journal of fish biology》2023,102(1):27-43
Understanding the ecological role of species with overlapping distributions is central to inform ecosystem management. Here we describe the diet, trophic level and habitat use of three sympatric stingrays, Hypanus guttatus, H. marianae and H. berthalutzae, through combined stomach content and stable isotope (δ13C and δ15N) analyses. Our integrated approach revealed that H. guttatus is a mesopredator that feeds on a diverse diet of benthic and epibenthic marine and estuarine organisms, principally bivalve molluscs, Alpheus shrimp and teleost fishes. Isotopic data supported movement of this species between marine and estuarine environments. H. berthalutzae is also a marine generalist feeder, but feeds primarily on teleost fishes and cephalopods, and consequently occupies a higher trophic level. In contrast, H. marianae is a mesopredator specialized on shrimps and polychaetas occurring only in the marine environment and occupying a low niche breadth. While niche overlap occurred, the three stingrays utilized the same prey resources at different rates and occupied distinct trophic niches, potentially limiting competition for resources and promoting coexistence. These combined data demonstrate that these three mesopredators perform different ecological roles in the ecosystems they occupy, limiting functional redundancy. 相似文献