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991.
Vanessa Kappel da Silva Betânia Souza de Freitas Arethuza da Silva Dornelles Laura Roesler Nery Lucio Falavigna Rafael Dal Ponte Ferreira Maurício Reis Bogo Jaime Eduardo Cecílio Hallak Antônio Waldo Zuardi José Alexandre S. Crippa Nadja Schröder 《Molecular neurobiology》2014,49(1):222-233
We have recently shown that chronic treatment with cannabidiol (CBD) was able to recover memory deficits induced by brain iron loading in a dose-dependent manner in rats. Brain iron accumulation is implicated in the pathogenesis of neurodegenerative diseases, including Parkinson’s and Alzheimer’s, and has been related to cognitive deficits in animals and human subjects. Deficits in synaptic energy supply have been linked to neurodegenerative diseases, evidencing the key role played by mitochondria in maintaining viable neural cells and functional circuits. It has also been shown that brains of patients suffering from neurodegenerative diseases have increased expression of apoptosisrelated proteins and specific DNA fragmentation. Here, we have analyzed the expression level of brain proteins involved with mitochondrial fusion and fission mechanisms (DNM1L and OPA1), the main integral transmembrane protein of synaptic vesicles (synaptophysin), and caspase 3, an apoptosis-related protein, to gain a better understanding of the potential of CBD in restoring the damage caused by iron loading in rats. We found that CBD rescued iron-induced effects, bringing hippocampal DNM1L, caspase 3, and synaptophysin levels back to values comparable to the control group. Our results suggest that iron affects mitochondrial dynamics, possibly trigging synaptic loss and apoptotic cell death and indicate that CBD should be considered as a potential molecule with memory-rescuing and neuroprotective properties to be used in the treatment of cognitive deficits observed in neurodegenerative disorders. 相似文献
992.
Ana Luiza Freire Cintia Lacerda Ramos Euziclei Gonzaga de Almeida Whasley Ferreira Duarte Rosane Freitas Schwan 《World journal of microbiology & biotechnology》2014,30(2):567-577
Yakupa is a traditional non-alcoholic cassava beverage produced by Brazilian Amerindians. In this work the microbial dynamics and metabolites involved in yakupa fermentation were investigated by PCR-denaturing gradient gel electrophoresis and chromatography analysis, respectively. The lactic acid bacteria (LAB) population was higher than yeast in the beginning of fermentation (5 log CFU mL?1 and 3 log CFU mL?1, respectively) and after 36 h both population increased reaching 7 log CFU mL?1, remaining constant until 60 h. Culture dependent and independent methods in combination identified the bacteria Lactobacillus fermentum, L. plantarum, Weissela cibaria and W. confusa, and yeasts Saccharomyces cerevisiae and Pichia kudriavzevii. Maltose (41.2 g L?1), ethanol (6.5 g L?1) and lactic acid (7.8 g L?1) were the most abundant compounds identified by high performance liquid chromatography. Aldehydes, acids, alcohols and esters were identified by gas chromatography flame ionization detection. By the metabolites and PCA analysis we may assign the beverage’s flavor to the microbial metabolism. Heterolactic LAB and S. cerevisiae dominated the yakupa fermentation, being responsible for the organoleptic characteristics of the final product. This is the first time that the microbial dynamics and physicochemical parameters were investigated in the yakupa beverage and it may contribute to the future selection of starter cultures to perform yakupa fermentations. 相似文献
993.
Marla S. Carvalho Jansen Zuanon Efrem J. G. Ferreira 《Environmental Biology of Fishes》2014,97(1):59-68
The natural history of Pygidianops amphioxus de Pinna and Kirovskyi (Neotropical Ichthyology 9:493–504, 2011), a highly specialized sand-dwelling catfish species, was studied based on underwater observations in a small forest stream in the central Amazon. Information on the feeding and reproductive biology was obtained by means of analyses of preserved specimens. These miniature catfishes remained buried in the sand at the bottom of the stream and were never observed swimming in open water. The catfish consumed small benthic invertebrates, particularly Chironomidae larvae and Harpacticoida copepods, which were most likely captured by suction feeding inside the sand banks. Pygidianops amphioxus displays sexual dimorphism in the shape of the urogenital papilla and in the body length, with adult females being relatively longer than males. Sexually mature females were found throughout the year and carried a small number of proportionally very large oocytes. A short duration (24 h) experiment conducted in aquaria revealed that these small catfishes exhibit the predominantly nocturnal habits typical of most Siluriformes. 相似文献
994.
Fabiana Carvalho de Souza José Eduardo Meireles Cláudia Barbieri Ferreira Mendonça Vania Gonçalves-Esteves 《Plant Systematics and Evolution》2014,300(8):1759-1770
The small South-American genus Poecilanthe has a striking morphological diversity in leaf type, inflorescence, seed morphology and chemical composition. Recent phylogenetic work also shows that Poecilanthe is paraphyletic. Despite the importance of palynology to better understand morphological diversity and potentially inform evolutionary analyses, the pollen morphology of Poecilanthe and most of its close relatives is unknown. This study uses light and electronic microscopy to describe the pollen morphology of eight species of Poecilanthe and the four related genera Ormosia, Harpalyce, Clathrotropis and Cyclolobium. We found pollen grains colpate only in four species of Poecilanthe and Harpalyce brasiliana and colporate pollen grains in the other four Poecilanthe species and the other related genera (Ormosia, Clathrotropis and Cyclolobium). An identification key for pollen of all species is provided. Using principal component analyses (PCA) we found that pollen grains of the Poecilanthe have considerable diversity. However, only limited correspondence between the PCA clusters and the Poecilanthe clades was found, suggesting that pollinic characters do not reflect evolutionary history in this group. 相似文献
995.
Gregório Miguel Ferreira de Camargo Raphael Bermal Costa Lucia Galvão de Albuquerque Luciana Correia de Almeida Regitano Fernando Baldi Humberto Tonhati 《Gene》2014
Reproductive traits have a high economic value and it is interesting to include them in the selection objectives of an animal breeding program. These traits generally show low heritability and molecular markers may therefore be used in genetic evaluations to improve the accuracy of predictions. The JY-1 gene is expressed in the oocyte and it is associated with folliculogenesis and early embryo development. It has been suggested to affect reproductive traits. In this study, exons 1 and 2 of the JY-1 gene were studied in 385 Nellore females by PCR-sequencing. Seventeen polymorphisms were identified. After analysis of linkage disequilibrium, association tests were performed between eight SNPs and the occurrence of early pregnancy, age at first calving, days to calving, and reconception of primiparous heifers. Seven SNPs were significant for three traits. The most significant was chr29:12,999 T/A (p = 0.003) which was associated with the occurrence of early pregnancy. This SNP might be involved in protein translation inhibition since it affects the initial methionine codon. The JY-1, an oocyte specific gene, influences reproductive traits; further studies investigating other regions of the gene or other genes expressed in tissues of the female reproductive system would be interesting to be performed. 相似文献
996.
Kleber Juvenal Silva Farias Paula Renata Lima Machado Renato Ferreira de Almeida Junior Ana Alice de Aquino Benedito Antônio Lopes da Fonseca 《Microbiology and immunology》2014,58(6):318-326
The objective of this study was to investigate the use of chloroquine (CLQ) as an antiviral agent against dengue. Chloroquine, an amine acidotropic drug known to affect intracellular exocytic pathways by increasing endosomal pH, was used in the in vitro treatment of U937 cells infected with dengue virus type 2 (DENV‐2). Viral replication was assessed by quantification of virus produced through detection of copy numbers of DENV‐2 RNA, plaque assay and indirect immunofluorescence. qRT‐PCR and plaque assays were used to quantify the DENV‐2 load in infected U937 cells after CLQ treatment. It was found that a dose of 50 μg/mL of CLQ was not toxic to the cells and resulted in significantly less virus production in infected U937 cells than occurred in untreated cells. In the present work, CLQ was effective against DENV‐2 replication in U937 cells, and also caused a statistically significant reduction in expression of proinflammatory cytokines. The present study indicates that CLQ may be used to reduce viral yield in U937 cells. 相似文献
997.
A. R. Ferreira J. M. L. Dias M. von Stosch J. Clemente A. E. Cunha Rui Oliveira 《Bioprocess and biosystems engineering》2014,37(4):629-639
In this paper, we implemented a model-based optimization platform for fast development of Pichia pastoris cultures employing batch-to-batch control and hybrid semi-parametric modeling. We illustrate the methodology with a P. pastoris GS115 strain expressing a single-chain antibody fragment (scFv) by determining the optimal time profiles of temperature, pH, glycerol feeding and methanol feeding that maximize the endpoint scFv titer. The first hybrid model was identified from data of six exploratory experiments carried out in a pilot 50-L reactor. This model was subsequently used to maximize the final scFv titer of the proceeding batch employing a dynamic optimization program. Thereupon, the optimized time profiles of control variables were implemented in the pilot reactor and the resulting new data set was used to re-identify the hybrid model and to re-optimize the next batch. The iterative batch-to-batch optimization was stopped after 4 complete optimized batches with the final scFv titer stabilizing at 49.5 mg/L. In relation to the baseline batch (executed according to the Pichia fermentation guidelines by Invitrogen) a more than fourfold increase in scFv titer was achieved. The biomass concentration at induction and the methanol feeding rate profile were found to be the most critical control degrees of freedom to maximize scFv titer. 相似文献
998.
Wagner Gonzaga Gonçalves Kenner Morais Fernandes Marcelo Silva Barcellos Fernanda Pereira Silva Marcos Jorge Magalhães-Junior José Cola Zanuncio Gustavo Ferreira Martins José Eduardo Serrão 《Comptes rendus biologies》2014,337(6):365-372
Bumblebees are widely distributed across the world and have great economic and ecological importance as pollinators in the forest as well as in agriculture. The insect midgut consists of three cell types, which play various important roles in digestion, absorption, and hormone production. The present study characterized the anterior and posterior midgut regions of the bumblebee, Bombus morio. The digestive, regenerative and endocrine cells in the midgut showed regional differences in their number, nuclear size, as well as the size of the striated border. Ultrastructurally, the digestive cells contained many mitochondria and long microvilli; however, in the anterior midgut region, these cells showed dilated basal labyrinths with a few openings for the hemocoel, whereas the labyrinths of the basal posterior region remained inverse characteristics. Thus, the characterization of the midgut of B. morio supported an ecto-endoperitrophic circulation, contributing to a better understanding of the digestive process in this bee. 相似文献
999.
Pedro M. Anastácio Miriam P. Ferreira Filipe Banha César Capinha João E. Rabaça 《Aquatic Ecology》2014,48(1):1-10
Human transport and active dispersal of the red swamp crayfish (Procambarus clarkii) contribute to its rapid spread. However, some small aquatic organisms can be transported by birds. We made two hypotheses related to waterbird-mediated passive dispersal of juvenile crayfish. The first is that, depending on water depth, recently hatched crayfish can attach to ducks, initiating passive external transport (i.e., ectozoochory). The second is that recently hatched crayfish can survive bird flight, being affected by crayfish features, flight distance, and environmental conditions. A first experiment tested the attachment of juvenile crayfish to ducks at different water depths by using a freshly dead duck and tanks with crayfish. Another set of three experiments tested crayfish survival during air transportation. To simulate bird flight, we first used a vehicle moving at bird flight speed, and we then used trained pigeons. Several flight distances, environmental conditions, and crayfish sizes were tested. Our results showed that juvenile crayfish were capable of clinging to duck feathers and were transported when ducks were removed from the water. Furthermore, some juveniles of P. clarkii were able to survive long-distance transport when suspended outside a moving vehicle or when transported by birds. The probability of success was affected by water depth, crayfish size, distance travelled, and relative humidity. Our results support the occurrence of passive transportation of this invader by means of attachment to birds. These findings indicate that waterbird-mediated passive dispersal should be taken into account to explain P. clarkii’s rapid spread and should be considered when managing its invasions. 相似文献