955 resultados para Anti-ADN topoisomérase I


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There is a significant lack of sociological research in Spain about anti-Semitism. At the same time there are alarming anti-Semitic tendencies and anti-Jewish stereotypes which are above the European average. This article aims to explain this lack of sociological research about anti-Semitism in Spain. Therefore two types of explications are offered: on the one hand side some structural problems will be shown which sociology in general had since its beginnings and which complicate the understanding of anti-Semitism. Furthermore explications regarding the specific social and historic situation in Spain and of Spanish sociology in particular will be exposed. It will be shown that for its rationalistic character and with the exception of very few authors – who are considered marginalized for practical research – sociology in general has had enormous problems in understanding anti-Semitism. The specific historic situation, Francoism, the dispute about the historic memory and the delayed institutionalisation of sociology could also explain the lack of sociological interest in the topic especially in Spain. The article shows that the study of anti-Semitism is not only relevant for struggling against this burden of society in many of its variants. Furthermore, thinking about anti-Semitism can help sociology to recognise its own epistemological problems. It can serve to criticise and improve instruments of sociological research by showing the limitations of the sociological approach and to uncover the importance of interdisciplinary research for understanding specific social phenomena. In that sense, anti-Semitism, far from being a marginal subject, can be considered a key topic in the process of civilisation and it can help us to decipher the contemporary Spanish society.

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Fasciola hepatica secretes cathepsin L proteases that facilitate the penetration of the parasite through the tissues of its host, and also participate in functions such as feeding and immune evasion. The major proteases, cathepsin L1 (FheCL1) and cathepsin L2 (FheCL2) are members of a lineage that gave rise to the human cathepsin Ls, Ks and Ss, but while they exhibit similarities in their substrate specificities to these enzymes they differ in having a wider pH range for activity and an enhanced stability at neutral pH. There are presently 13 Fasciola cathepsin L cDNAs deposited in the public databases representing a gene family of at least seven distinct members, although the temporal and spatial expression of each of these members in the developmental stage of F. hepatica remains unclear. Immunolocalisation and in situ hybridisation studies, using antibody and DNA probes, respectively, show that the vast majority of cathepsin L gene expression is carried out in the epithelial cells lining the parasite gut. Within these cells the enzyme is packaged into secretory vesicles that release their contents into the gut lumen for the purpose of degrading ingested host tissue and blood. Liver flukes also express a novel multi-domain cystatin that may be involved in the regulation of cathepsin L activity. Vaccine trials in both sheep and cattle with purified native FheCL1 and FheCL2 have shown that these enzymes can induce protection, ranging from 33 to 79%, to experimental challenge with metacercariae of F. hepatica, and very potent anti-embryonation/hatch rate effects that would block parasite transmission. In this article we review the vaccine trials carried out over the past 8 years, the role of antibody and T cell responses in mediating protection and discuss the prospects of the cathepsin Ls in the development of first generation recombinant liver fluke vaccines. Author Keywords: Helminths; Trematodes; Parasites; Cathepsins; Proteases; Vaccines; Immunology; Biochemistry

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Background: Chronic inhibition of nitric oxide (NO) synthesis is associated with hypertension, myocardial oxidative stress and hypertrophic remodeling. Up-regulation of the cardiomyocyte adrenomedullin (AM) / intermedin (IMD) receptor signaling cascade is also apparent in NO-deficient cardiomyocytes: augmented expression of AM and receptor activity modifying proteins RAMP2 and RAMP3 is prevented by blood pressure normalization while that of RAMP1 and intermedin (IMD) is not, indicating that the latter is regulated by a pressure-independent mechanism. Aims: to verify the ability of an anti-oxidant intervention to normalize cardiomyocyte oxidant status and to investigate the influence of such an intervention on expression of AM, IMD and their receptor components in NO-deficient cardiomyocytes. Methods: NO synthesis inhibitor, NG-nitro-L-arginine methyl ester (L-NAME, 35mg/kg/day) was given to rats for 8 weeks, with/without con-current administration of antioxidants (Vitamin C (25mg/kg/day) and Tempol (25mg/kg/day)). Results: In left ventricular cardiomyocytes isolated from L-NAME treated rats, increased oxidative stress was indicated by augmented (3.6 fold) membrane protein oxidation, enhanced expression of catalytic and regulatory subunits of pro-oxidant NADPH oxidases (NOX1, NOX2) and compensatory increases in expression of anti-oxidant glutathione peroxidase and Cu/Zn superoxide dismutases (SOD1, SOD3). Vitamin C plus Tempol did not reduce systolic blood pressure but normalized augmented plasma levels of IMD, but not of AM, and in cardiomyocytes: (i) abolished increased membrane protein oxidation; (ii) normalized augmented expression of prepro-IMD and RAMP1, but not prepro-AM, RAMP2 and RAMP3; (iii) attenuated (by 42%) increased width and normalized expression of hypertrophic markers, skeletal-�-actin and prepro-endothelin-1 similarly to blood pressure normalization but in contrast to blood pressure normalization did not attenuate augmented brain natriuretic peptide (BNP) expression. Conclusion: normalization specifically of augmented IMD/RAMP1 expression in NO-deficient cardiomyocytes by antioxidant intervention in the absence of blood pressure reduction indicates that these genes are likely to be induced directly by myocardial oxidative stress. Although oxidative stress contributed to cardiomyocyte hypertrophy, induction of IMD and RAMP1 is unlikely to be secondary to cardiomyocyte hypertrophy.

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Studies on the immunoglobulin (Ig)E immune responses to the gastric nematode, Teladorsagia circumcincta, have demonstrated a major high molecular weight allergen (HMWTc). Cross reactive allergens of similar MW were demonstrated for Trichostrongylus colubriformis and Cooperia curticei, but not for Haemonchus contortus. Purification of HMWTc was achieved by gel-filtration chromatography, and nonreducing SDS-PAGE and Western blot analysis revealed two closely associated bands with a molecular weight of approximately 140-150?kDa. Reduction showed four IgE reactive bands of 120, 50, 45 and 30?kDa, and deglycosylation abrogated the immunoreactivity of the 120 and 30?kDa bands. Ultrastructural immunolocalization by electron microscopy revealed that the IgE reactivity was confined to the cuticular surface of the infective (L3) larvae. ELISA studies to determine the IgE anti-HMWTc responses in lambs during their first grazing season, demonstrated significantly higher IgE antibody in lambs with low accumulative faecal egg count (FEC) compared to animals with high accumulative FEC. These studies provide evidence for a protective function of IgE antibody in Teladorsagia infections in lambs.

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α1-antitrypsin (α1-AT) deficiency is a genetic disease which manifests as early-onset emphysema or liver disease. Although the majority of α1-AT is produced by the liver, it is also produced by bronchial epithelial cells, amongst others, in the lung. Herein, we investigate the effects of mutant Z α1-AT (ZAAT) expression on apoptosis in a human bronchial epithelial cell line (16HBE14o-) and delineate the mechanisms involved.

Control, M variant α1-AT (MAAT)- or ZAAT-expressing cells were assessed for apoptosis, caspase-3 activity, cell viability, phosphorylation of Bad, nuclear factor (NF)-κB activation and induced expression of a selection of pro- and anti-apoptotic genes.

Expression of ZAAT in 16HBE14o- cells, like MAAT, inhibited basal and agonist-induced apoptosis. ZAAT expression also inhibited caspase-3 activity by 57% compared with control cells (p = 0.05) and was a more potent inhibitor than MAAT. Whilst ZAAT had no effect on the activity of Bad, its expression activated NF-κB-dependent gene expression above control or MAAT-expressing cells. In 16HBE14o- cells but not HEK293 cells, ZAAT upregulated expression of cIAP-1, an upstream regulator of NF-κB. cIAP1 expression was increased in ZAAT versus MAAT bronchial biopsies.

The data suggest a novel mechanism by which ZAAT may promote human bronchial epithelial cell survival.

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BACKGROUND: On the basis of preclinical studies of NC-6004, a cisplatin-incorporated micellar formulation, we hypothesised that NC-6004 could show lower toxicity than cisplatin and show greater anti-tumour activity in phase I study. METHODS: A total of 17 patients were recruited in a range of advanced solid tumour types. NC-6004 was administered intravenously (i.v.) every 3 weeks. The dose escalation started at 10?mg?m(-2) and was increased up to 120?mg?m(-2) according to the accelerated titration method and modified Fibonacci method. RESULTS: One dose-limiting toxicity (DLT) occurred in a patient who was given 90?mg?m(-2) of NC-6004, otherwise any significant cisplatin-related toxicity was not observed or generally mild toxicity was observed. Despite the implementation of post-hydration and pre-medication regimen, renal impairment and hypersensitivity reactions still developed at 120?mg?m(-2), which led to the conclusion that the maximum tolerated dose was 120?mg?m(-2), and the recommended dose was 90?mg?m(-2), although DLT was not defined as per protocol. Stable disease was observed in seven patients. The maximum concentration and area under the concentration-time curve of ultrafilterable platinum at 120?mg?m(-2) NC-6004 were 34-fold smaller and 8.5-fold larger, respectively, than those for cisplatin. CONCLUSION: The delayed and sustained release of cisplatin after i.v. administration contributes to the low toxicity of NC-6004.

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The guanine nucleotide exchange factor C3G, along with the CrkII adaptor protein, mediates GTP activation of the small GTPase proteins Rap1 and R-Ras, facilitating their activation of downstream signaling pathways, which had been found to be important in the pathogenesis of glomerulonephritis. We found that expression of C3G protein was upregulated in glomerular epithelial cells in an experimental model of accelerated anti-GBM antibody-induced glomerulonephritis expression. To determine the consequence of its increased expression, we transfected C3G (using adenoviral constructs) into cultured glomerular epithelial cells and measured the activated forms (i.e., GTP-bound) forms of Rap1 and R-Ras. Activation of Rap1 was not affected by C3G; however, the basal level of GTP-bound R-Ras was decreased. Further, C3G over-expression enhanced the activation of R-Ras in response to endothelin. Overexpression of C3G also led to a significant reduction in glomerular epithelial cell spreading and decreased the cells' E-cadherin expression and augmented their migration. We found that C3G was overexpressed in accelerated anti-GBM antibody-induced glomerulonephritis and suggest that this modulates glomerular epithelial cell morphology and behavior.

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Behavioral effects of a novel anti-inflammatory SEN1176 were investigated. This pyrrolo[3,2-e][1,2,4]triazolo[1,5-a]pyrimidine suppresses amyloid-ß (Aß)1-42-induced macrophage production of nitric oxide, TNF-a, IL-1ß, and IL-6 in a dose-dependent fashion, an activity profile consistent with SEN1176 being a neuroinflammation inhibitor. Using male Sprague-Dawley rats, SEN1176 was examined relative to detrimental behavioral effects induced following bilateral intrahippocampal (IH) injections of aggregated Aß1-42. The rats were trained to respond under an alternating-lever cyclic-ratio (ALCR) schedule of food reinforcement, enabling measurement of parameters of operant performance that reflect aspects of learning and memory. Under the ALCR schedule, orally administered SEN1176 at 5, 20, or 30 mg/kg was effective in reducing the behavioral deficit caused by bilateral IH aggregated Aß1-42 injections in a dose-related manner over a 90-day treatment period. SEN1176 at 20 and 30 mg/kg significantly reduced lever switching errors and, at doses of 5, 10, and 30 mg/kg, significantly reduced incorrect lever perseverations, indicating a reduction of the behavioral deficit induced as a result of inflammation following IH Aß1-42 injections. When treatment with SEN1176 was instigated 30 days after IH Aß1-42 injections, it resulted in progressive protection, and withdrawal of SEN1176 treatment 60 days after IH Aß1-42 injections revealed partial retention of the protective effect. SEN1176 also significantly reduced numbers of activated astrocytes adjacent to the aggregated Aß1-42 injection sites. These results indicate the potential of SEN1176 for alleviating chronic neuroinflammatory processes related to brain Aß deposition that affect learning and memory in Alzheimer's disease.

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Mitochondria produce cellular energy but also free-radicals, which damage cells despite an array of endogenous anti-oxidants. In Northern Europe, the mitochondrial haplogroup J has been related to longevity in nonagenarians and centenarians but also with age-related disease. Hypertension is an important contributor to atherosclerotic-related diseases and its pathogenesis is associated with increased oxidative stress. In this study, we questioned whether J haplogroup octo/nonagenarians from the Belfast Elderly Longitudinal Free-living Elderly STudy (BELFAST) study showed evidence of protective blood pressure or anti-oxidant profile which might explain their longevity advantage. Briefly, in a cross-sectional study, community-living, mentally alert (Folstein >25/30), octo/nonagenarian subjects, recruited for good health, were enlisted and consented as part of the BELFAST study, for blood pressure, anthropometric measurements and blood sampling. DNA typing for mitochondrial haplotypes was carried out with measurements for enzymatic and non-enzymatic antioxidants. J haplogroup carriers showed lower systolic blood pressure and glutathione peroxidase activity (Gpx) with higher folate measurements. There was no change in urate, bilirubin, albumin or nutrition-related antioxidants-selenium or vitamins A, C and a and ß carotene. BELFAST study mtDNA J haplogroup octo/nonagenarians showed lower blood pressure and reduced glutathione peroxidase activity and higher folate, but no change for other antioxidants. These findings are of interest in view of mtDNA J haplogroup's association with increased age in some previous studies.

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Nitric oxide (NO) is important for the regulation of a number of diverse biological processes, including vascular tone, neurotransmission, inflammatory cell responsiveness, defence against invading pathogens and wound healing. Transition metal exchanged zeolites are nanoporous materials with high-capacity storage properties for gases such as NO. The NO stores are liberated upon contact with aqueous environments, thereby making them ideal candidates for use in biological and clinical settings. Here, we demonstrate the NO release capacity and powerful bactericidal properties of a novel NO-storing Zn2+-exchanged zeolite material at a 50 wt.% composition in a polytetrafluoroethylene polymer. Further to our published data showing the anti-thrombotic effects of a similar NO-loaded zeolite, this study demonstrates the antibacterial properties of NO-releasing zeolites against clinically relevant strains of bacteria, namely Gram-negative Pseudomonas aeruginosa and Gram-positive methicillin-sensitive and methicillin-resistant Staphylococcus aureus and Clostridium difficile. Thus our study highlights the potential of NO-loaded zeolites as biocompatible medical device coatings with anti-infective properties. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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Type II DNA topoisomerases catalyse DNA double-strand cleavage, passage and re-ligation to effect topological changes. There is considerable interest in elucidating topoisomerase II roles, particularly as these proteins are targets for anti-cancer drugs. Here we uncover a role for topoisomerase IIa in RNA polymerase I-directed ribosomal RNA gene transcription, which drives cell growth and proliferation and is upregulated in cancer cells. Our data suggest that topoisomerase IIa is a component of the initiation-competent RNA polymerase Iß complex and interacts directly with RNA polymerase I-associated transcription factor RRN3, which targets the polymerase to promoter-bound SL1 in pre-initiation complex formation. In cells, activation of rDNA transcription is reduced by inhibition or depletion of topoisomerase II, and this is accompanied by reduced transient double-strand DNA cleavage in the rDNA-promoter region and reduced pre-initiation complex formation. We propose that topoisomerase IIa functions in RNA polymerase I transcription to produce topological changes at the rDNA promoter that facilitate efficient de novo pre-initiation complex formation.

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In an epidemiological survey from South India, 936 serum samples were tested for IgG against recombinant baculovirus-expressed VP6 proteins from human group A and group C rotaviruses. The overall seroprevalence for group A was 100% and for group C was 25.32% (95% CI 22.64-28.21). The lowest seroprevalence for group C was in children aged