103 research outputs found

    RT-level fast fault simulator

    Get PDF
    In this paper a new fast fault simulation technique is presented for calculation of fault propagation through HLPs (High Level Primitives). ROTDDs (Reduced Ordered Ternary Decision Diagrams) are used to describe HLP modules. The technique is implemented in the HTDD RT-level fault simulator. The simulator is evaluated with some ITC99 benchmarks. A hypothesis is proved that a test set coverage of physical failures can be anticipated with high accuracy when RTL fault model takes into account optimization strategies that are used in CAE system applied

    Validation of reactive embedded systems against specification requirements

    Get PDF
    In this paper a method of automatic generation of test scenarios for verification of specification requirements (temporal and functional) for reactive embedded systems is presented

    Content Based Image Retrieval using Query by Approximate Shape

    Full text link

    Immunoproteomics and surfaceomics of the adult tapeworm Hymenolepis diminuta

    Get PDF
    In cestodiasis, mechanical and molecular contact between the parasite and the host activates the immune response of the host and may result in inflammatory processes, leading to ulceration and intestinal dysfunctions. The aim of the present study was to identify antigenic proteins of the adult cestode Hymenolepis diminuta by subjecting the total protein extracts from adult tapeworms to 2DE immunoblotting (two-dimensional electrophoresis combined with immunoblotting) using sera collected from experimentally infected rats. A total of 36 protein spots cross-reacting with the rat sera were identified using LC-MS/MS. As a result, 68 proteins, including certain structural muscle proteins (actin, myosin, and paramyosin) and moonlighters (heat shock proteins, kinases, phosphatases, and glycolytic enzymes) were identified; most of these were predicted to possess binding and/or catalytic activity required in various metabolic and cellular processes, and reported here as potential antigens of the adult cestode for the first time. As several of these antigens can also be found at the cell surface, the surface-associated proteins were extracted and subjected to in-solution digestion for LC-MS/MS identification (surfaceomics). As a result, a total of 76 proteins were identified, from which 31 proteins, based on 2DE immunoblotting, were predicted to be immunogenic. These included structural proteins actin, myosin and tubulin as well as certain moonlighting proteins (heat-shock chaperones) while enzymes with diverse catalytic activities were found as the most dominating group of proteins. In conclusion, the present study shed new light into the complexity of the enteric cestodiasis by showing that the H. diminuta somatic proteins exposed to the host possess immunomodulatory functions, and that the immune response of the host could be stimulated by diverse mechanisms, involving also those triggering protein export via yet unknown pathways.Peer reviewe

    Is Endothelial Nitric Oxide Synthase a Moonlighting Protein Whose Day Job is Cholesterol Sulfate Synthesis? Implications for Cholesterol Transport, Diabetes and Cardiovascular Disease

    Get PDF
    Theoretical inferences, based on biophysical, biochemical, and biosemiotic considerations, are related here to the pathogenesis of cardiovascular disease, diabetes, and other degenerative conditions. We suggest that the “daytime” job of endothelial nitric oxide synthase (eNOS), when sunlight is available, is to catalyze sulfate production. There is a striking alignment between cell types that produce either cholesterol sulfate or sulfated polysaccharides and those that contain eNOS. The signaling gas, nitric oxide, a well-known product of eNOS, produces pathological effects not shared by hydrogen sulfide, a sulfur-based signaling gas. We propose that sulfate plays an essential role in HDL-A1 cholesterol trafficking and in sulfation of heparan sulfate proteoglycans (HSPGs), both critical to lysosomal recycling (or disposal) of cellular debris. HSPGs are also crucial in glucose metabolism, protecting against diabetes, and in maintaining blood colloidal suspension and capillary flow, through systems dependent on water-structuring properties of sulfate, an anionic kosmotrope. When sunlight exposure is insufficient, lipids accumulate in the atheroma in order to supply cholesterol and sulfate to the heart, using a process that depends upon inflammation. The inevitable conclusion is that dietary sulfur and adequate sunlight can help prevent heart disease, diabetes, and other disease conditions

    AVALIAÇÃO DA IMUNIZAÇÃO COM CATEPSINA L3 FRENTE À FASCIOLOSE EXPERIMENTAL

    Get PDF
    Fasciolose acomete principalmente bovinos e ovinos e é responsável por importantes perdas econômicas. Objetivou-se testar em ratos e bovinos a proteção do antígeno recombinante Catepsina L3 frente à infecção experimental por Fasciola hepatica. Os ratos foram divididos nos grupos: 1) imunizados; 2) adjuvante e 3) controle. Os bovinos foram divididos nos grupos: 4) imunizados e 5) adjuvante. Avaliaram-se ovos por grama nas fezes e contagem parasitária nos ratos, ganho de peso diário e contagem parasitária nos bovinos. Observou-se baixo índice de proteção, não alcançando nível suficiente para utilização comercial do antígeno

    Two distinct regions in Staphylococcus aureus GatCAB guarantee accurate tRNA recognition

    Get PDF
    In many prokaryotes the biosynthesis of the amide aminoacyl-tRNAs, Gln-tRNAGln and Asn-tRNAAsn, proceeds by an indirect route in which mischarged Glu-tRNAGln or Asp-tRNAAsn is amidated to the correct aminoacyl-tRNA catalyzed by a tRNA-dependent amidotransferase (AdT). Two types of AdTs exist: bacteria, archaea and organelles possess heterotrimeric GatCAB, while heterodimeric GatDE occurs exclusively in archaea. Bacterial GatCAB and GatDE recognize the first base pair of the acceptor stem and the D-loop of their tRNA substrates, while archaeal GatCAB recognizes the tertiary core of the tRNA, but not the first base pair. Here, we present the crystal structure of the full-length Staphylococcus aureus GatCAB. Its GatB tail domain possesses a conserved Lys rich motif that is situated close to the variable loop in a GatCAB:tRNAGln docking model. This motif is also conserved in the tail domain of archaeal GatCAB, suggesting this basic region may recognize the tRNA variable loop to discriminate Asp-tRNAAsn from Asp-tRNAAsp in archaea. Furthermore, we identified a 310 turn in GatB that permits the bacterial GatCAB to distinguish a U1–A72 base pair from a G1–C72 pair; the absence of this element in archaeal GatCAB enables the latter enzyme to recognize aminoacyl-tRNAs with G1–C72 base pairs

    Ex vivo correction of selenoprotein N deficiency in rigid spine muscular dystrophy caused by a mutation in the selenocysteine codon

    Get PDF
    Premature termination of translation due to nonsense mutations is a frequent cause of inherited diseases. Therefore, many efforts were invested in the development of strategies or compounds to selectively suppress this default. Selenoproteins are interesting candidates considering the idiosyncrasy of the amino acid selenocysteine (Sec) insertion mechanism. Here, we focused our studies on SEPN1, a selenoprotein gene whose mutations entail genetic disorders resulting in different forms of muscular diseases. Selective correction of a nonsense mutation at the Sec codon (UGA to UAA) was undertaken with a corrector tRNASec that was engineered to harbor a compensatory mutation in the anticodon. We demonstrated that its expression restored synthesis of a full-length selenoprotein N both in HeLa cells and in skin fibroblasts from a patient carrying the mutated Sec codon. Readthrough of the UAA codon was effectively dependent on the Sec insertion machinery, therefore being highly selective for this gene and unlikely to generate off-target effects. In addition, we observed that expression of the corrector tRNASec stabilized the mutated SEPN1 transcript that was otherwise more subject to degradation. In conclusion, our data provide interesting evidence that premature termination of translation due to nonsense mutations is amenable to correction, in the context of the specialized selenoprotein synthesis mechanism

    Direct AMPK activation corrects NASH in rodents through metabolic effects and direct action on inflammation and fibrogenesis

    Get PDF
    No approved therapies are available for nonalcoholic steatohepatitis (NASH). Adenosine monophosphate–activated protein kinase (AMPK) is a central regulator of cell metabolism; its activation has been suggested as a therapeutic approach to NASH. Here we aimed to fully characterize the potential for direct AMPK activation in preclinical models and to determine mechanisms that could contribute to efficacy for this disease. A novel small-molecule direct AMPK activator, PXL770, was used. Enzyme activity was measured with recombinant complexes. De novo lipogenesis (DNL) was quantitated in vivo and in mouse and human primary hepatocytes. Metabolic efficacy was assessed in ob/ob and high-fat diet–fed mice. Liver histology, biochemical measures, and immune cell profiling were assessed in diet-induced NASH mice. Direct effects on inflammation and fibrogenesis were assessed using primary mouse and human hepatic stellate cells, mouse adipose tissue explants, and human immune cells. PXL770 directly activated AMPK in vitro and reduced DNL in primary hepatocytes. In rodent models with metabolic syndrome, PXL770 improved glycemia, dyslipidemia, and insulin resistance. In mice with NASH, PXL770 reduced hepatic steatosis, ballooning, inflammation, and fibrogenesis. PXL770 exhibited direct inhibitory effects on pro-inflammatory cytokine production and activation of primary hepatic stellate cells. Conclusion: In rodent models, direct activation of AMPK is sufficient to produce improvements in all core components of NASH and to ameliorate related hyperglycemia, dyslipidemia, and systemic inflammation. Novel properties of direct AMPK activation were also unveiled: improved insulin resistance and direct suppression of inflammation and fibrogenesis. Given effects also documented in human cells (reduced DNL, suppression of inflammation and stellate cell activation), these studies support the potential for direct AMPK activation to effectively treat patients with NASH

    Myeloid ATP citrate lyase regulates macrophage inflammatory responses in vitro without altering inflammatory disease outcomes

    Get PDF
    Macrophages are highly plastic, key regulators of inflammation. Deregulation of macrophage activation can lead to excessive inflammation as seen in inflammatory disorders like atherosclerosis, obesity, multiple sclerosis and sepsis. Targeting intracellular metabolism is considered as an approach to reshape deranged macrophage activation and to dampen the progression of inflammatory disorders. ATP citrate lyase (Acly) is a key metabolic enzyme and an important regulator of macrophage activation. Using a macrophage-specific Acly-deficient mouse model, we investigated the role of Acly in macrophages during acute and chronic inflammatory disorders. First, we performed RNA sequencing to demonstrate that Acly-deficient macrophages showed hyperinflammatory gene signatures in response to acute LPS stimulation in vitro. Next, we assessed endotoxin-induced peritonitis in myeloid-specific Acly-deficient mice and show that, apart from increased splenic Il6 expression, systemic and local inflammation were not affected by Acly deficiency. Also during obesity, both chronic low-grade inflammation and whole-body metabolic homeostasis remained largely unaltered in mice with Acly-deficient myeloid cells. Lastly, we show that macrophage-specific Acly deletion did not affect the severity of experimental autoimmune encephalomyelitis (EAE), an experimental model of multiple sclerosis. These results indicate that, despite increasing inflammatory responses in vitro, macrophage Acly deficiency does not worsen acute and chronic inflammatory responses in vivo. Collectively, our results indicate that caution is warranted in prospective long-term treatments of inflammatory disorders with macrophage-specific Acly inhibitors. Together with our earlier observation that myeloid Acly deletion stabilizes atherosclerotic lesions, our findings highlight that therapeutic targeting of macrophage Acly can be beneficial in some, but not all, inflammatory disorders.Host-parasite interactio
    corecore