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231.
Rotllant J Ruane NM Dinis MT Canario AV Power DM 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2006,143(3):375-381
The effect of the catecholamines, adrenaline and noradrenaline, on sea bass (Dicentrarchus labrax) and sea bream (Sparus auratus) interrenal cortisol production was studied in vitro using a dynamic superfusion system technique. Increasing concentrations of catecholamines (10(-6), 10(-8) and 10(-10) M) stimulated cortisol production in a dose-dependent manner, in sea bass only. The increase in cortisol production stimulated by adrenaline (10(-6) M) and noradrenaline (10(-6) M) was inhibited by sotalol (2 x 10(-5) M), but not by prazosin suggesting that catecholamines stimulate cortisol release through the beta-receptor subtype. To evaluate catecholamine-induced signal transduction in head kidney cells, measurements of cAMP production and [H3]myo-inositol incorporation were determined in head kidney cell suspensions. Adrenaline and noradrenaline (10(-6) M) increased cAMP production, but had no effect on total inositol phosphate accumulation. These results indicate that catecholamines released from the chromaffin cells within the interrenal tissue may act as a paracrine factor to stimulate interrenal steroidogenesis in the sea bass. 相似文献
232.
Joana Paixão Teresa C.P. Dinis Leonor M. Almeida 《Chemico-biological interactions》2012,199(3):192-200
Anthocyanins are the most abundant flavonoid constituents of fruits and vegetables and several epidemiological studies suggest that the consumption of these compounds protect against several diseases, including vascular disorders. Previously, we have reported that anthocyanins are able to counteract peroxynitrite-induced apoptotic effects in endothelial cells through inhibition of several crucial signaling cascades, upstream and downstream of mitochondria. Following these studies, here we investigated possible effects of malvidin-3-glucoside, one of the main dietary anthocyanins, on NO bioavailability and on peroxynitrite-induced NF-kB activation in the same cell model.Our results show that treatment of bovine arterial endothelial cells with malvidin-3-glucoside up-regulated eNOS mRNA, leading to the enhancement of eNOS activity and NO production, an effect even greater when cells were further stimulated with peroxynitrite. On the other hand, in these activated endothelial cells, malvidin-3-glucoside suppressed pro-inflammatory mediators, namely iNOS expression/NO biosynthesis, COX-2 expression and IL-6 production, through inhibition of NF-kB activation.These findings suggest a potential role of malvidin-3-glucoside in NO balance and in inhibition of pro-inflammatory signaling pathways, supporting its benefits in cardiovascular health and pointing to anthocyanins as a promising tool for development of functional foods and nutraceuticals to improve endothelial function. 相似文献
233.
Ravi K. R. Marreddy Eric R. Geertsma Hjalmar P. Permentier Joao P. C. Pinto Jan Kok Bert Poolman 《PloS one》2010,5(4)
Background
Understanding the biogenesis pathways for the functional expression of recombinant proteins, in particular membrane proteins and complex multidomain assemblies, is a fundamental issue in cell biology and of high importance for future progress in structural genomics. In this study, we employed a proteomic approach to understand the difference in expression levels for various multidomain membrane proteins in L. lactis cells grown in complex and synthetic media.Methodology/Principal Findings
The proteomic profiles of cells growing in media in which the proteins were expressed to high or low levels suggested a limitation in the availability of branched-chain amino acids, more specifically a too limited capacity to accumulate these nutrients. By supplying the cells with an alternative path for accumulation of Ile, Leu and/or Val, i.e., a medium supplement of the appropriate dipeptides, or by engineering the transport capacity for branched-chain amino acids, the expression levels could be increased several fold.Conclusions
We show that the availability of branched chain amino acids is a critical factor for the (over)expression of proteins in L. lactis. The forward engineering of cells for functional protein production required fine-tuning of co-expression of the branched chain amino acid transporter. 相似文献234.
Towards a global barcode library for Lymantria (Lepidoptera: Lymantriinae) tussock moths of biosecurity concern 总被引:1,自引:0,他引:1
deWaard JR Mitchell A Keena MA Gopurenko D Boykin LM Armstrong KF Pogue MG Lima J Floyd R Hanner RH Humble LM 《PloS one》2010,5(12):e14280
Background
Detecting and controlling the movements of invasive species, such as insect pests, relies upon rapid and accurate species identification in order to initiate containment procedures by the appropriate authorities. Many species in the tussock moth genus Lymantria are significant forestry pests, including the gypsy moth Lymantria dispar L., and consequently have been a focus for the development of molecular diagnostic tools to assist in identifying species and source populations. In this study we expand the taxonomic and geographic coverage of the DNA barcode reference library, and further test the utility of this diagnostic method, both for species/subspecies assignment and for determination of geographic provenance of populations.Methodology/Principal Findings
Cytochrome oxidase I (COI) barcodes were obtained from 518 individuals and 36 species of Lymantria, including sequences assembled and generated from previous studies, vouchered material in public collections, and intercepted specimens obtained from surveillance programs in Canada. A maximum likelihood tree was constructed, revealing high bootstrap support for 90% of species clusters. Bayesian species assignment was also tested, and resulted in correct assignment to species and subspecies in all instances. The performance of barcoding was also compared against the commonly employed NB restriction digest system (also based on COI); while the latter is informative for discriminating gypsy moth subspecies, COI barcode sequences provide greater resolution and generality by encompassing a greater number of haplotypes across all Lymantria species, none shared between species.Conclusions/Significance
This study demonstrates the efficacy of DNA barcodes for diagnosing species of Lymantria and reinforces the view that the approach is an under-utilized resource with substantial potential for biosecurity and surveillance. Biomonitoring agencies currently employing the NB restriction digest system would gather more information by transitioning to the use of DNA barcoding, a change which could be made relatively seamlessly as the same gene region underlies both protocols. 相似文献235.
Sophie Quérouil Luís Freitas Ana Dinis Filipe Alves Irma Cascão Rui Prieto Mónica A. Silva Sara Magalhães José A. Matos Ricardo S. Santos 《European Journal of Wildlife Research》2010,56(2):151-158
Biological samples of free-ranging dolphins are increasingly used to gain information on population structure and ecology.
In small cetaceans, the gender of individuals usually cannot be determined at sea, and population sex ratio has to be inferred
indirectly. We used molecular sexing to determine the gender of 340 biopsy samples of bottlenose dolphins, Tursiops truncatus, spotted dolphins, Stenella frontalis, and common dolphins, Delphinus delphis, collected around the Azores and Madeira. Sex ratio was globally skewed in favor of males, and differed between species and
archipelagos. Skew was probably influenced by the selectivity of biopsy collectors and seasonal or year-round predominance
of males in natural populations. Skew was also influenced by sampling duration and intensity. In the Azores, when several
samples were successively collected within the same group, the proportion of female samples decreased as a function of sample
order. This trend indicated a tendency for females to increasingly avoid the boat while samples were being collected. It showed
that males and females reacted differently to the perturbation caused by the biopsy sampling process (i.e., sample collection
and driving style). 相似文献
236.
237.
Raquel dos Santos Inês Iria Ana M. Manuel Ana P. Leandro Catarina A. C. Madeira Joao Goncalves Ana Luísa Carvalho Ana Cecília A. Roque 《Biotechnology journal》2020,15(9)
One of the trends in downstream processing comprises the use of “anything‐but‐chromatography” methods to overcome the current downfalls of standard packed‐bed chromatography. Precipitation and magnetic separation are two techniques already proven to accomplish protein purification from complex media, yet never used in synergy. With the aim to capture antibodies directly from crude extracts, a new approach combining precipitation and magnetic separation is developed and named as affinity magnetic precipitation. A precipitation screening, based on the Hofmeister series, and a commercial precipitation kit are tested with affinity magnetic particles to assess the best condition for antibody capture from human serum plasma and clarified cell supernatant. The best conditions are obtained when using PEG3350 as precipitant at 4 °C for 1 h, reaching 80% purity and 50% recovery of polyclonal antibodies from plasma, and 99% purity with 97% recovery yield of anti‐TNFα mAb from cell supernatants. These results show that the synergetic use of precipitation and magnetic separation can represent an alternative for the efficient capture of antibodies. 相似文献
238.
Laurie Laugier Ludmila Rodrigues Pinto Ferreira Frederico Moraes Ferreira Sandrine Cabantous Amanda Farage Frade Joao Paulo Nunes Rafael Almeida Ribeiro Pauline Brochet Priscila Camillo Teixeira Ronaldo Honorato Barros Santos Edimar A. Bocchi Fernando Bacal Darlan da Silva Cndido Vanessa Escolano Maso Helder I. Nakaya Jorge Kalil Edecio Cunha-Neto Christophe Chevillard 《PLoS neglected tropical diseases》2020,14(12)
Chronic Chagas disease cardiomyopathy (CCC), an especially aggressive inflammatory dilated cardiomyopathy caused by lifelong infection with the protozoan Trypanosoma cruzi, is a major cause of cardiomyopathy in Latin America. Although chronic myocarditis may play a major pathogenetic role, little is known about the molecular mechanisms responsible for its severity. The aim of this study is to study the genes and microRNAs expression in tissues and their connections in regards to the pathobiological processes. To do so, we integrated for the first time global microRNA and mRNA expression profiling from myocardial tissue of CCC patients employing pathways and network analyses. We observed an enrichment in biological processes and pathways associated with the immune response and metabolism. IFNγ, TNF and NFkB were the top upstream regulators. The intersections between differentially expressed microRNAs and differentially expressed target mRNAs showed an enrichment in biological processes such as Inflammation, inflammation, Th1/IFN-γ-inducible genes, fibrosis, hypertrophy, and mitochondrial/oxidative stress/antioxidant response. MicroRNAs also played a role in the regulation of gene expression involved in the key cardiomyopathy-related processes fibrosis, hypertrophy, myocarditis and arrhythmia. Significantly, a discrete number of differentially expressed microRNAs targeted a high number of differentially expressed mRNAs (>20) in multiple processes. Our results suggest that miRNAs orchestrate expression of multiple genes in the major pathophysiological processes in CCC heart tissue. This may have a bearing on pathogenesis, biomarkers and therapy. 相似文献
239.
240.
Gustavo Martelli-Palomino Joao A. Pancotto Yara C. Muniz Celso T. Mendes-Junior Erick C. Castelli Juliana D. Massaro Irene Krawice-Radanne Isabelle Poras Vera Rebmann Edgardo D. Carosella Nathalie Rouas-Freiss Philippe Moreau Eduardo A. Donadi 《PloS one》2013,8(10)
HLA-G molecule has well-recognized tolerogenic properties, and the encoding gene shows lower frequency of polymorphism at the coding region but higher variability at regulatory 5’ and 3’ untranslated (3’UTR) regions. At least three 3’UTR polymorphic sites have been associated with HLA-G mRNA regulation, including the 14 base pair (14bp) Insertion/Deletion, +3142C-G and +3187A-G. We studied the association of polymorphic sites at 3’UTR (sequencing analysis, encompassing the 14bp Ins-Del/+3003T-C/+3010C-G/+3027C-A/+3035C-T/+3142C-G/+3187A-G/+3196C-G polymorphic sites) with plasma soluble HLA-G levels (sHLA-G, detected by ELISA) in 187 French and 153 Brazilian healthy individuals. Allele and genotype frequencies were closely similar in both populations; however, Brazilians showed a higher HLA-G 3’UTR haplotype diversity. Considering sHLA-G levels in both populations altogether, individuals presenting 14bp Del/Del showed higher levels compared to 14bpIns/Ins genotype (P <0.05); those presenting +3010C/G showed higher levels compared to the +3010C-C genotype (P< 0.05); those presenting +3027C-C showed higher levels than the +3027A-A genotype (P< 0.05); and those bearing +3035C-C showed higher levels compared to the +3035C-T (P < 0.01) and +3035T-T (P < 0.05) genotypes. The analyses of 3’UTR haplotypes showed that UTR-1 (DelTGCCCGC) was associated with higher expression of sHLA-G, whereas UTR-5 (InsTCCTGAC) and UTR-7 (InsTCATGAC) with lower expression and other UTRs (UTR-2/3/4/6) exhibited intermediate levels. Since the differential expression of HLA-G may be beneficial or harmful depending on the underlying condition, the identification of individuals genetically programmed to differentially express HLA-G may help on defining novel strategies to control the immune response against the underlying disorder. 相似文献