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131.
Júlia D. Moreira Luisa Knorr Marcelo Ganzella Ana Paula Thomazi Carolina G. de Souza Débora G. de Souza Carolina F. Pitta Tadeu Mello e Souza Susana Wofchuk Elaine Elisabetsky Lúcia Vinadé Marcos L.S. Perry Diogo O. Souza 《Neurochemistry international》2010,56(6-7):753-759
Essential omega-3 polyunsaturated fatty acids (ω3) are crucial to brain development and function, being relevant for behavioral performance. In the present study we examined the influence of dietary ω3 in the development of the glutamatergic system and on behavior parameters in rats. Female rats received isocaloric diets, either with ω3 (ω3 group) or a ω3 deficient diet (D group). In ontogeny experiments of their litters, hippocampal immunocontent of ionotropic NMDA and AMPA glutamatergic receptors subunits (NR2 A\B and GluR1, respectively) and the alpha isoform of the calcium-calmodulin protein kinase type II (αCaMKII) were evaluated. Additionally, hippocampal [3H]glutamate binding and uptake were assessed. Behavioral performance was evaluated when the litters were adult (60 days old), through the open-field, plus-maze, inhibitory avoidance and flinch-jump tasks. The D group showed decreased immunocontent of all proteins analyzed at 02 days of life (P2) in comparison with the ω3 group, although the difference disappeared at 21 days of life (except for αCaMKII, which content normalized at 60 days old). The same pattern was found for [3H]glutamate binding, whereas [3H]glutamate uptake was not affected. The D group also showed memory deficits in the inhibitory avoidance, increased in the exploratory pattern in open-field, and anxiety-like behavior in plus-maze. Taken together, our results suggest that dietary ω3 content is relevant for glutamatergic system development and for behavioral performance in adulthood. The putative correlation among the neurochemical and behavioral alterations caused by dietary ω3 deficiency is discussed. 相似文献
132.
Tiago Collares Vinicius Farias Campos Fabiana Kömmling Seixas Paulo V. Cavalcanti Odir A. Dellagostin Heden Luiz M. Moreira João Carlos Deschamps 《Journal of biosciences》2010,35(1):39-47
The silver catfish (Rhamdia quelen) is an endemic American fish species. The sperm of each species has its own peculiarities and biological characteristics,
which influence the success of mass DNA transfer methods. Our objective in this study was to evaluate different sperm-mediated
gene transfer (SMGT) methods to obtain transgenic silver catfish. Different treatments for the incorporation of a foreign
pEGFP plasmid group were used: (1) dehydrated/rehydrated (DR), (2) dehydrated/rehydrated/electroporated (DRE), (3) electroporated
(E), (4) incubated with seminal plasma (INC); and (5) incubated in the absence of seminal plasma (INCSP). Sperm motility,
time of activity duration (TAD), fertilization rate (FR), hatching rate (HR) and sperm morphology were also evaluated. The
polymerase chain reaction (PCR) positivity rates for the presence of the transgene were: DRE 60%; DR 40%; E 25%; INC 5% and
INCSP 25%. The rates of embryo EGFP expression were: DRE 63%; DR 44%; E 34%; INC 8% and INCSP 38%. The fertilization rate
in the control and DRE treatments groups were higher than in the DR group, but the E, INC and INCSP treatment groups had the
lowest rate. The hatching rates of the DRE, DR and control groups were higher than in the INCSP, INC and E treatment groups
(P>0.05). There were no differences among the DRE and DR, E and DR, E and INCSP groups in expression and PCR positivity rates
of enhanced green fluorescent protein (EGFP) in embryos. Scanning electron microscopy also did not show any change in sperm
morphology among treatment groups. To the best of our knowledge, this is the first report on transgene transmission of exogenous
DNA into silver catfish larvae through SMGT technology. 相似文献
133.
Camila B. Piantino Juliana M. Sousa-Canavez Victor Srougi Fernanda Salvadori Raphael Kato Pedro Paulo R. Ayres Miguel Srougi Luiz Heraldo Camara-Lopes Gilka Jorge Figaro Gattás Cintia Fridman Fernanda de Toledo Isaque Santana Kátia Ramos Moreira Leite 《In vitro cellular & developmental biology. Animal》2010,46(2):131-139
Bladder cancer (BC) is the fourth most common cancer in the USA. In Brazil, BC represents 3% of the total existing carcinomas in the population and represents the second highest incidence among urological tumors. The majority of bladder cancer cell lines available were derived from Caucasians and established in the seventies or eighties. Thus, neoplasia development in these cells likely occurred in environment conditions vastly different than today. In the present study, we report the establishment and characterization of three Brazilian bladder cancer cell lines (BexBra1, BexBra2, and BexBra4). These cell lines may be helpful for dissecting the genetic and epigenetic aspects that trigger the progression of BC. Moreover, the development of a Brazilian representative of the disease will allow us to investigate the potential inter-racial differences of malignancy-associated phenotypes in bladder cancer. 相似文献
134.
Alejandro Gallego Luis Rodríguez Almudena Hospido María Teresa Moreira Gumersindo Feijoo 《The International Journal of Life Cycle Assessment》2010,15(1):32-43
Background, aim, and scope
Life cycle assessment (LCA) has traditionally been considered a site-independent tool, but nowadays, there is a trend towards making LCA more site-dependent. Site-dependent characterization factors have been calculated for regional impact categories such as acidification, terrestrial and aquatic eutrophication, and smog. Specifically, for aquatic eutrophication, characterization factors have been proposed for large geographical areas (mainly European and North American countries). Those factors are not detailed enough for countries which present large geographical, climatic, and economical variability such as Spain. Therefore, this work aims to calculate the characterization factors and the normalization reference for aquatic eutrophication at a regional level, using Galicia (NW Spain), a region with increasing problems of eutrophication, as a case study. Finally, the comparison of the factors obtained here with literature values will be used to analyze the influence of spatial differentiation with increasing coverage of the causality chain. 相似文献135.
Felipe F.D. Oliveira Diego C.B.D. Santos Alexandre A.M. Lapis José R. Corrêa Alexandre F. Gomes Fabio C. Gozzo Paulo F. Moreira Virgínia C. de Oliveira Frank H. Quina Brenno A.D. Neto 《Bioorganic & medicinal chemistry letters》2010,20(20):6001-6007
Newly designed 2,1,3-benzothiadiazole-containing fluorescent probes with four excited state intramolecular proton transfer (ESIPT) sites were successfully tested in live cell-imaging assays using a confluent monolayer of human stem-cells (tissue). All tested dyes were compared with the commercially available DAPI and gave far better results. 相似文献
136.
André Almeida Maria Jo?o Moreira Sónia Soares Maria de Lurdes Delgado Jo?o Figueiredo Elisabete Silva António Castro José Manuel Correida Da Cosa 《The Korean journal of parasitology》2010,48(1):43-48
Cryptosporidium and Giardia are 2 protozoan parasites responsible for waterborne diseases outbreaks worldwide. In order to assess the prevalence of these protozoans in drinking water samples in the northern part of Portugal and the risk of human infection, we have established a long term program aiming at pinpointing the sources of surface water, drinking water, and environmental contamination, working with the water-supply industry. Total 43 sources of drinking water samples were selected, and a total of 167 samples were analyzed using the Method 1623. Sensitivity assays regarding the genetic characterization by PCR and sequencing of the genes, 18S SSU rRNA, for Cryptosporidium spp. and β,-giardin for G. duodenalis were set in the laboratory. According to the defined criteria, molecular analysis was performed over 4 samples. Environmental stages of the protozoa were detected in 25.7% (43 out of 167) of the water samples, 8.4% (14 out of 167) with cysts of Giardia, 10.2% (17 out of 167) with oocysts of Cryptosporidium and 7.2% (12 out of 167) for both species. The mean concentrations were 0.1-12.7 oocysts of Cryptosporidium spp. per 10 L and 0.1-108.3 cysts of Giardia duodenalis per 10 L. Our results suggest that the efficiency in drinking water plants must be ameliorated in their efficiency in reducing the levels of contamination. We suggest the implementation of systematic monitoring programs for both protozoa. To authors'' knowledge, this is the first report evaluating the concentration of environmental stages of Cryptosporidium and Giardia in drinking water samples in the northern part of Portugal. 相似文献
137.
138.
Tailane Sant’Anna Moreira Valéria Pereira de Sousa Maria Bernadete Riemma Pierre 《AAPS PharmSciTech》2010,11(2):621-629
Transdermal delivery of non-steroidal anti-inflammatory drugs may be an interesting strategy for delivering these drugs to
the diseased site, but it would be ineffective due to low skin permeability. We investigated whether oleic acid (OA), a lipid
penetration enhancer in poloxamer gels named poloxamer-based delivery systems (PBDS), can improve lumiracoxib (LM) delivery
to/through the skin. The LM partition coefficient (K) studies were carried out in order to evaluate the drug lipophilicity grade (K
octanol/buffer), showing values >1 which demonstrated its high lipophilicity. Both in vitro percutaneous absorption and skin retention studies of LM were measured in the presence or absence of OA (in different concentrations)
in PBDS using porcine ear skin. The flux of in vitro percutaneous absorption and in vitro retention of LM in viable epidermis increased in the presence of 10.0% (w/w) OA in 25.0% (w/w) poloxamer gel. In vivo cutaneous irritation potential was carried out in rabbits showing that this formulation did not provide primary or cumulative
cutaneous irritability in animal model. The results showed that 25.0% poloxamer gel containing 10.0% OA is potential transdermal
delivery system for LM. 相似文献
139.
Rogério S. Rosada Ana P. Moreira Fabiani G. Frantz Raj K. Puri Aquilur Rahman Theodore J. Standiford Carlos R. Zárate-Bladés Célio L. Silva Cory M. Hogaboam 《PloS one》2010,5(1)
Background
We have previously explored a therapeutic strategy for specifically targeting the profibrotic activity of IL-13 during experimental pulmonary fibrosis using a fusion protein comprised of human IL-13 and a mutated form of Pseudomonas aeruginosa exotoxin A (IL13-PE) and observed that the intranasal delivery of IL13-PE reduced bleomycin-induced pulmonary fibrosis through its elimination of IL-13-responsive cells in the lung. The aim of the present study was to determine whether the presence of an immune response to P. aeruginosa and/or its exotoxin A (PE) would diminish the anti-fibrotic properties of IL13-PE.Methodology/Principal Findings
Fourteen days after P. aeruginosa infection, C57BL/6 mice were injected with bleomycin via the intratracheal route. Other groups of mice received 4 doses of saline or IL13-PE by either intranasal or intraperitoneal application, and were challenged i.t. with bleomycin 28 days later. At day 21 after bleomycin, all mice received either saline vehicle or IL13-PE by the intranasal route and histopatological analyses of whole lung samples were performed at day 28 after bleomycin. Intrapulmonary P. aeruginosa infection promoted a neutralizing IgG2A and IgA antibody response in BALF and serum. Surprisingly, histological analysis showed that a prior P. aeruginosa infection attenuated the development of bleomycin-induced pulmonary fibrosis, which was modestly further attenuated by the intranasal administration of IL13-PE. Although prior intranasal administration of IL13-PE failed to elicit an antibody response, the systemic administration of IL13-PE induced a strong neutralizing antibody response. However, the prior systemic sensitization of mice with IL13-PE did not inhibit the anti-fibrotic effect of IL13-PE in fibrotic mice.Conclusions
Thus, IL13-PE therapy in pulmonary fibrosis works regardless of the presence of a humoral immune response to Pseudomonas exotoxin A. Interestingly, a prior infection with P. aeruginosa markedly attenuated the pulmonary fibrotic response suggesting that the immune elicitation by this pathogen exerts anti-fibrotic effects. 相似文献140.