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51.
Sinara Artico Julia Lambret-Frotté Sarah Muniz Nardeli Osmundo Brilhante Oliveira-Neto Maria Fátima Grossi-de-Sa Marcio Alves-Ferreira 《Plant Molecular Biology Reporter》2014,32(3):630-643
Engineering of plant protection requires well-characterized tissue-specific promoters for the targeted expression of insecticidal resistance genes. Herein, we describe the isolation of five different fragments of promoters of three distinct flower-specific cotton (Gossypium hirsutum) genes. Expression analyses of the three genes GhPME-like1, GhβGal-like1 and GhPL-like1 revealed that they are expressed highly in flowers buds ranging from 4 to 12 mm in size. Several putative regulatory cis-elements were identified in the promoter regions, including elements involved in the control of tissue-specific gene expression in pollen grains and fruits. In vivo analyses of these promoters were performed using the heterologous plant system Arabidopsis thaliana by fusing them with the gene uidA (GUS). GUS staining in Arabidopsis tissues revealed that their expression was restricted to anthers, with the majority of expression in pollen grains and in the upper portion of the carpels and siliques. A comparison between a CaMV35S::GUS constitutive promoter and the promoters isolated in this study revealed that the cotton promoters were more active and were specific to flowers and fruits, which are organs that are preferentially attacked by important pest insects such as the boll weevil (Anthonomus grandis). The activity of the promoters was also confirmed using transient expression assays in flower buds of G. hirsutum. The promoters of GhPME-like1, GhβGal-like1 and GhPL-like1 are specific to reproductive tissues and could represent important biotechnological tools for controlling insect pests, in particular the cotton boll weevil, which attacks floral and fruit tissues. 相似文献
52.
Adeliane Castro da Costa Abadio de Oliveira Costa-Júnior Fábio Muniz de Oliveira Sarah Veloso Nogueira Joseane Damaceno Rosa Danilo Pires Resende André Kipnis Ana Paula Junqueira-Kipnis 《PloS one》2014,9(11)
Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) that is a major public health problem. The vaccine used for TB prevention is Mycobacterium bovis bacillus Calmette-Guérin (BCG), which provides variable efficacy in protecting against pulmonary TB among adults. Consequently, several groups have pursued the development of a new vaccine with a superior protective capacity to that of BCG. Here we constructed a new recombinant BCG (rBCG) vaccine expressing a fusion protein (CMX) composed of immune dominant epitopes from Ag85C, MPT51, and HspX and evaluated its immunogenicity and protection in a murine model of infection. The stability of the vaccine in vivo was maintained for up to 20 days post-vaccination. rBCG-CMX was efficiently phagocytized by peritoneal macrophages and induced nitric oxide (NO) production. Following mouse immunization, this vaccine induced a specific immune response in cells from lungs and spleen to the fusion protein and to each of the component recombinant proteins by themselves. Vaccinated mice presented higher amounts of Th1, Th17, and polyfunctional specific T cells. rBCG-CMX vaccination reduced the extension of lung lesions caused by challenge with Mtb as well as the lung bacterial load. In addition, when this vaccine was used in a prime-boost strategy together with rCMX, the lung bacterial load was lower than the result observed by BCG vaccination. This study describes the creation of a new promising vaccine for TB that we hope will be used in further studies to address its safety before proceeding to clinical trials. 相似文献
53.
M. Dubois E. Sampaio J. F. Gerard P. Y. Quenette J. Muniz 《International journal of primatology》2000,21(1):85-102
We recorded the responses of the members of a captive group of wedge-capped capuchins to novel and familiar objects placed in different parts of their cage in a study of the spatial dependency of activity with objects. We focused on behavioral pattern variability across subjects and across object location. Results show that, according to the location of the object, a great deal of within-subject response variability exists. The dominant male was slow to interact physically with objects and presented social-like behaviors—essentially grooming—towards objects in only one site. Implicit to the ethological approach is the assumption that consistent spatial location is irrelevant or, at best, of little importance to the definition of stimuli. Nevertheless, stimuli would be best considered as perturbations insofar as the significance of an object or event depends on where and when it is encountered. In order to evaluate how monkey cognition operates, it seems essential to investigate the role of the primate's own spatial structure. As a working hypothesis, we introduce the processes of spatial facilitation and inhibition and suggest that they affect how an individual interacts with objects and events. 相似文献
54.
Sandra Jesus Elizangela H. Fragal Adley F. Rubira Edvani C. Muniz Artur J. M. Valente Olga Borges 《AAPS PharmSciTech》2018,19(1):101-113
This report extensively explores the benefits of including chitosan into poly-ε-caprolactone (PCL) nanoparticles (NPs) to obtain an improved protein/antigen delivery system. Blend NPs (PCL/chitosan NPs) showed improved protein adsorption efficacy (84%) in low shear stress and aqueous environment, suggesting that a synergistic effect between PCL hydrophobic nature and the positive charges of chitosan present at the particle surface was responsible for protein interaction. Additionally, thermal analysis suggested the blend NPs were more stable than the isolated polymers and cytotoxicity assays in a primary cell culture revealed chitosan inclusion in PCL NPs reduced the toxicity of the delivery system. A quantitative 6-month stability study showed that the inclusion of chitosan in PCL NPs did not induce a change in adsorbed ovalbumin (OVA) secondary structure characterized by the increase in the unordered conformation (random coil), as it was observed for OVA adsorbed to chitosan NPs. Additionally, the slight conformational changes occurred, are not expected to compromise ovalbumin secondary structure and activity, during a 6-month storage even at high temperatures (45°C). In simulated biological fluids, PCL/chitosan NPs showed an advantageous release profile for oral delivery. Overall, the combination of PCL and chitosan characteristics provide PCL/chitosan NPs valuable features particularly important to the development of vaccines for developing countries, where it is difficult to ensure cold chain transportation and non-parenteral formulations would be preferred. 相似文献
55.
Serafina Salvati Massimo Sanchez Lorenzo Malvezzi Campeggi †Gerda Suchanek ‡Helene Breitschop ‡Hans Lassmann 《Journal of neurochemistry》1996,67(4):1744-1750
Abstract: Our previous work showed an early development of behavioral reflexes in rats whose mothers had been fed, during pregnancy and lactation, a lipid fraction extracted from yeast grown on n -alkanes (which contain 50% odd-chain fatty acids) in comparison with controls fed a margarine diet. To clarify whether the observed changes might be linked to an early myelination, we have investigated mRNAs involved in myelin synthesis in the brains of offspring at 5 days of age by northern blot and in situ hybridization. Northern blot analysis showed that proteolipid protein (PLP) and myelin oligodendrocyte glycoprotein (MOG) mRNAs were higher in animals on the lipid diet compared with controls. In situ hybridization with probes specific for PLP, myelin basic protein, and MOG mRNA showed significantly higher numbers of positive cells in test animals compared with controls in all brain regions. This study shows an acceleration of myelinogenesis induced by dietary lipids. These data can give a new insight in the therapeutical approaches involved to promote repair in demyelinating diseases. 相似文献
56.
Development of egg PC/cholesterol/α-tocopherol liposomes with ionic gradients to deliver ropivacaine
Camila Morais Gonçalves da Silva Leonardo Fernandes Fraceto Michelle Franz-Montan Verônica Muniz Couto Bruna Renata Casadei Cíntia Maria Saia Cereda 《Journal of liposome research》2016,26(1):1-10
Context: Ropivacaine (RVC) is an aminoamide local anesthetic widely used in surgical procedures. Studies with RVC encapsulated in liposomes and complexed in cyclodextrins have shown good results, but in order to use RVC for lengthy procedures and during the postoperative period, a still more prolonged anesthetic effect is required.Objective: This study therefore aimed to provide extended RVC release and increased upload using modified liposomes.Materials and methods: Three types of vesicles were studied: (i) large multilamellar vesicle (LMV), (ii) large multivesicular vesicle (LMVV) and (iii) large unilamellar vesicle (LUV), prepared with egg phosphatidylcholine/cholesterol/α-tocopherol (4:3:0.07?mol%) at pH 7.4. Ionic gradient liposomes (inside: pH 5.5, pH 5.5?+?(NH4)2SO4 and pH 7.4?+?(NH4)2SO4) were prepared and showed improved RVC loading, compared to conventional liposomes (inside: pH 7.4).Results and discussion: An high-performance liquid chromatography analytical method was validated for RVC quantification. The liposomes were characterized in terms of their size, zeta potential, polydispersion, morphology, RVC encapsulation efficiency (EE(%)) and in vitro RVC release. LMVV liposomes provided better performance than LMV or LUV. The best formulations were prepared using pH 5.5 (LMVV 5.5in) or pH 7.4 with 250?mM (NH4)2SO4 in the inner aqueous core (LMVV 7.4in?+?ammonium sulfate), enabling encapsulation of as much as 2% RVC, with high uptake (EE(%) ~70%) and sustained release (~25?h).Conclusion: The encapsulation of RVC in ionic gradient liposomes significantly extended the duration of release of the anesthetic, showing that this strategy could be a viable means of promoting longer-term anesthesia during surgical procedures and during the postoperative period. 相似文献
57.
R Docampo R P Mason C Mottley R P Muniz 《The Journal of biological chemistry》1981,256(21):10930-10933
Nifurtimox is reduced by rat liver microsomes to a nitro anion-free radical as indicated by ESR spectroscopy. This subcellular fraction gives a steady state radical concentration which is proportional to the square root of the protein concentration, suggesting that the nifurtimox anion radical is a necessary intermediate in the reduction and that the radical decays through a nonenzymatic second order process. The steady state concentration of the anion radical in the microsomal system is not decreased by superoxide dismutase or catalase, thus indicating that neither the superoxide anion nor hydrogen peroxide is an intermediary in the generation of the anion radical. The steady state concentration of the anion radical in the microsomal system is also not altered in the presence of metyrapone or CO and is decreased in the presence of NADP+ and p-chloromercuribenzoate. This observation suggests that the formation of nifurtimox anion radical is mediated through NADPH-cytochrome P-450 (c) reductase and not by the cytochrome P-450 system. In accordance with this interpretation, a model system consisting of NADPH and FMN-reduced nifurtimox to the nitro anion-free radical. Nifurtimox anion radical generation is significantly stimulated by rat brain and testes homogenates. The enhanced free radical formation may be the basic cause of nifurtimox toxicity in mammals. 相似文献
58.
Renata Tiscoski Nesi Marina Valente Barroso Valdirene de Souza Muniz Ana Carolina de Arantes Marco Aurélio Martins Lycia de Brito Gitirana 《Free radical research》2017,51(7-8):708-722
Asthma is an allergic inflammation driven by the Th2 immune response with release of cytokines such as IL-4 and IL-13, which contribute to the airflow limitations and airway hyperresponsiveness (AHR). The involvement of oxidative stress in this process is well-established, but the specific role of the superoxide anion and nitric oxide in asthma are poorly understood. Thus, the aim of this study was to investigate the mechanisms underlying the superoxide anion/nitric oxide production and detoxification in a murine asthma model. BALB/c male mice were sensitised and challenged with ovalbumin (OVA). Pretreatments with either apocynin (14?mg/kg) or allopurinol (25?mg/kg) (superoxide anion synthesis inhibitors), aminoguanidine (50?mg/kg) (nitric oxide synthesis inhibitor) or diethyldithiocarbamate (100?mg/kg) (superoxide dismutase inhibitor) were performed 1?h before the challenge. Our data showed that apocynin and allopurinol ameliorated AHR and reduced eosinophil peroxidase, as well as IL-4 and IL-13 levels. Apocynin also abrogated leukocyte peribronchiolar infiltrate and increased IL-1β secretion. Aminoguanidine preserved lung function and shifted the Th2 to the Th1 response with a reduction of IL-4 and IL-13 and increase in IL-1β production. Diethyldithiocarbamate prevented neither allergen-induced AHR nor eosinophil peroxidase (EPO) generation. All treatments protected against oxidative damage observed by a reduction in TBARS levels. Taken together, these results suggest that AHR in an asthma model can be avoided by the down-regulation of superoxide anion and nitric oxide synthesis in a mechanism that is independent of a redox response. This down-regulation is also associated with a transition in the typical immunological Th2 response toward the Th1 profile. 相似文献
59.
Dr. A. Pintor S. Fortuna P. Lorenzini A. Pascale F. Battaini C. Avellino L. Malvezzi Campeggi S. Salvati 《Neurochemical research》1996,21(5):541-545
The influence of hypothyroidism (HO) induced by treatment with propylthiouracil on lipid composition, receptor responsiveness
of MI-muscarinic receptors (M1AChRs) and metabotropic glutamate receptors (mGluRs) as well as on protein kinase C (PKC) activity was investigated in the
cerebral cortex of Lewis rats. HO did not influence the lipid composition. There was a significant 2-fold increase of efficacy
and 6-fold decrease of potency of carbachol-induced inositol phosphate (IP) accumulation in HO, with respect to control rats.
The efficacy of trans-(1S,3R)-1-amino-1,3-cyclopentanedicarboxylic acid (ACPD)-induced IP accumulation was also higher in
HO (by 50%), without differences in EC50 values. The activities of soluble calcium-dependent and calcium-independent PKC were
higher in HO than in control rats (both roughly 30%); membrane-associated PKCs were not modified. The data indicate that HO
induces an increased responsiveness of M1AChRs and mGluRs and a rise in the soluble PKC activity that could be available and ready for translocation.
Department of Metabolism and Pathological Biochemistry. 相似文献
60.
In group living animals, especially among primates, there is consistent evidence that high-ranking males gain a higher reproductive output than low-ranking males. Primate studies have shown that male coalitions and sociality can impact male fitness; however, it remains unclear whether males could potentially increase their fitness by preferentially supporting and socializing with females. Here we investigate patterns of male interventions and the effect of coalitions and sociality on male fitness in rhesus macaques (Macaca mulatta) with particular focus on male-female interactions. We combined behavioural observations collected on Cayo Santiago with genetic data analysed for male reproductive output and relatedness. Our results revealed that the ten top-ranking males provided the majority of all male support observed. In contrast to other primates, male rhesus macaques mainly formed all-down coalitions suggesting that coalitions are less likely used to enhance male dominance. Males supporting females during and before their likely conception were not more likely to fertilize those females. We also found no evidence that males preferably support their offspring or other close kin. Interestingly, the most important predictor of male support was sociality, since opponents sharing a higher sociality index with a given male were more likely to be supported. Furthermore, a high sociality index of a given male-female dyad resulted in a higher probability of paternity. Overall, our results strengthen the evidence that sociality affects fitness in male primates, but also suggest that in species in which males queue for dominance, it is less likely that males derive fitness benefits from coalitions. 相似文献