1000 resultados para Indemnity against liability


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Tumour hypoxia is progressively emerging as a common feature of prostate tumours associated with poor prognosis. While the molecular basis of disease progression is increasingly well documented, the potential role of hypoxia in these processes remains poorly evaluated. By dissecting the impact of hypoxia-inducible factor 1 alpha on molecular responses, this review provides evidence for a powerful protecting role of oxygen deprivation against oxidative stress injury, androgen deprivation, chemotherapeutic and radiation cytotoxicity. We propose hypoxia as a potent tumour-induced shield against destruction and suggest its targeting may need to be routinely addressed in the management of prostate cancer.

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Cyber-attacks against Smart Grids have been found in the real world. Malware such as Havex and BlackEnergy have been found targeting industrial control systems (ICS) and researchers have shown that cyber-attacks can exploit vulnerabilities in widely used Smart Grid communication standards. This paper addresses a deep investigation of attacks against the manufacturing message specification of IEC 61850, which is expected to become one of the most widely used communication services in Smart Grids. We investigate how an attacker can build a custom tool to execute man-in-the-middle attacks, manipulate data, and affect the physical system. Attack capabilities are demonstrated based on NESCOR scenarios to make it possible to thoroughly test these scenarios in a real system. The goal is to help understand the potential for such attacks, and to aid the development and testing of cyber security solutions. An attack use-case is presented that focuses on the standard for power utility automation, IEC 61850 in the context of inverter-based distributed energy resource devices; especially photovoltaic (PV) generators.

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Prostate cancer is the second most common cause of cancer-associated deaths in men, and signaling via a transcription factor called androgen receptor (AR) is an important driver of the disease. Consequently, AR target genes are prominent candidates to be specific for prostate cancer and also important for the survival of the cancer cells. Here we assess the levels of all hexosamine biosynthetic pathway (HBP) enzymes in 15 separate clinical gene expression data sets and identify the last enzyme in the pathway, UDP-N-acetylglucosamine pyrophosphorylase 1 (UAP1), to be highly overexpressed in prostate cancer. We analyzed 3261 prostate cancers on a tissue microarray and found that UAP1 staining correlates negatively with Gleason score (P=0.0039) and positively with high AR expression (P<0.0001). Cells with high UAP1 expression have 10-fold increased levels of the HBP end-product, UDP-N-acetylglucosamine (UDP-GlcNAc). UDP-GlcNAc is essential for N-linked glycosylation occurring in the endoplasmic reticulum (ER) and high UAP1 expression associates with resistance against inhibitors of N-linked glycosylation (tunicamycin and 2-deoxyglucose) but not with a general ER stress-inducing agent, the calcium ionophore A23187. Knockdown of UAP1 expression re-sensitized cells towards inhibitors of N-linked glycosylation, as measured by proliferation and activation of ER stress markers. Taken together, we have identified an enzyme, UAP1, which is highly overexpressed in prostate cancer and protects cancer cells from ER stress conferring a growth advantage.

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Chemical activities of hydrophobic substances can determine the windows of environmental conditions over which microbial systems function and the metabolic inhibition of microorganisms by benzene and other hydrophobes can, paradoxically, be reduced by compounds that protect against cellular water stress (Bhaganna et al. in Microb Biotechnol 3:701-716, 2010; Cray et al. in Curr Opin Biotechnol 33:228-259, 2015a). We hypothesized that this protective effect operates at the macromolecule structure-function level and is facilitated, in part at least, by genome-mediated adaptations. Based on proteome profiling of the soil bacterium Pseudomonas putida, we present evidence that (1) benzene induces a chaotrope-stress response, whereas (2) cells cultured in media supplemented with benzene plus glycerol were protected against chaotrope stress. Chaotrope-stress response proteins, such as those involved in lipid and compatible-solute metabolism and removal of reactive oxygen species, were increased by up to 15-fold in benzene-stressed cells relative to those of control cultures (no benzene added). By contrast, cells grown in the presence of benzene + glycerol, even though the latter grew more slowly, exhibited only a weak chaotrope-stress response. These findings provide evidence to support the hypothesis that hydrophobic substances induce a chaotropicity-mediated water stress, that cells respond via genome-mediated adaptations, and that glycerol protects the cell's macromolecular systems. We discuss the possibility of using compatible solutes to mitigate hydrocarbon-induced stresses in lignocellulosic biofuel fermentations and for industrial and environmental applications.

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Therapies that are safe, effective, and not vulnerable to developing resistance are highly desirable to counteract bacterial infections. Host-directed therapeutics is an antimicrobial approach alternative to conventional antibiotics based on perturbing host pathways subverted by pathogens during their life cycle by using host-directed drugs. In this study, we identified and evaluated the efficacy of a panel of host-directed drugs against respiratory infection by nontypeable Haemophilus influenzae (NTHi). NTHi is an opportunistic pathogen that is an important cause of exacerbation of chronic obstructive pulmonary disease (COPD). We screened for host genes differentially expressed upon infection by the clinical isolate NTHi375 by analyzing cell whole-genome expression profiling and identified a repertoire of host target candidates that were pharmacologically modulated. Based on the proposed relationship between NTHi intracellular location and persistence, we hypothesized that drugs perturbing host pathways used by NTHi to enter epithelial cells could have antimicrobial potential against NTHi infection. Interfering drugs were tested for their effects on bacterial and cellular viability, on NTHi-epithelial cell interplay, and on mouse pulmonary infection. Glucocorticoids and statins lacked in vitro and/or in vivo efficacy. Conversely, the sirtuin-1 activator resveratrol showed a bactericidal effect against NTHi, and the PDE4 inhibitor rolipram showed therapeutic efficacy by lowering NTHi375 counts intracellularly and in the lungs of infected mice. PDE4 inhibition is currently prescribed in COPD, and resveratrol is an attractive geroprotector for COPD treatment. Together, these results expand our knowledge of NTHi-triggered host subversion and frame the antimicrobial potential of rolipram and resveratrol against NTHi respiratory infection.

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This chapter examines the nature and extent of violence experienced by women in Ireland during the Irish War of Independence (1919-1921) at the hands of both the Crown forces and the Irish Republican Army. It argues that targetted killings of women by either side was rare. The most common forms of such violence can be categorised as physical, gendered (cutting of hair) and psychological (intimidation and the killing of male relatives). It argues that there was a difference between gendered and sexual crime, the latter of which appears to have been very uncommon. A considerable part of the chapter uses theoretical literature on violence against women in conflict zones to explain why sexual violence was uncommon, arguing that neither side had much to gain from its employment, that the Crown forces were aware of the damage it could do to Britain's international reputation and that the terror tactics adopted by the Crown forces were sufficient to achieve their ends without resorting to rape. In regard to the IRA, the absence of any evidence of rape or sexual assault being perpetrated could be attributable to their Catholicism, reliance on support from the community, the efforts of the first Dáil to achieve foreign recognition of the Republic and the role of Cumann na mBan women in the guerrilla conflict. The historiography of women in the Irish revolution is also analysed.

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This study explored the effect of HPP (400 MPa/1 min) and a Weissella viridescens protective culture, alone or in conjunction, against Listeria monocytogenes in ready-to-eat (RTE) salads with different pH values (4.32 and 5.59) during storage at 4 and 12 °C. HPP was able to reduce the counts of the pathogen after treatment achieving approximately a 4.0 and 1.5 log CFU/g reduction in the low and higher pH RTE salad, respectively. However, L. monocytogenes was able to recover and grow during subsequent storage. W. viridescens grew in both RTE salads at both storage temperatures, with HPP resulting in only a small immediate reduction of W. viridescens ranging from 0.50 to 1.2 log CFU/g depending on the pH of the RTE salad. For the lower pH RTE salad, the protective culture was able to gradually reduce the L. monocytogenes counts during storage whereas for the higher pH RTE salad in some cases it delayed growth significantly or exerted a bacteriostatic effect. exerted a bacteriostatic effect. The results revealed that the increased storage temperature led to an increase in the inactivation/inhibition of L. monocytogenes in the presence of W. viridescens. The combination of HPP and W. viridescens is a promising strategy to control L. monocytogenes and can increase safety even when a break in the chill chain occurs.

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Introduction: Many neuropeptides are similar in size, amino acid composition and charge to antimicrobial peptides. It is therefore possible that the nervous system employs neuropeptides as antimicrobial agents by delivering them rapidly and precisely to innervated sites such as the dental pulp. Objectives: The aim of this study was to determine whether the neuropeptides substance P (SP), neurokinin A (NKA), calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP), which we have previously shown to be present in dental pulp, displayed antimicrobial activity against the cariogenic bacterium Streptococcus mutans and the endodontic bacterium Enterococcus faecalis. Methods: Neuropeptides were purchased from Bachem and utilised in antibacterial assays using a previously described ultra sensitive radial diffusion method. Results: Antimicrobial activity was identified as clear zones around neuropeptide-containing wells. NPY was found to exhibit antimicrobial against both Streptococcus mutans and Enterococcus faecalis. SP and VIP were shown to exhibit antimicrobial activity against Streptococcus mutans only. The neuropeptides NKA and CGRP did not show antimicrobial activity against either micro-organism. Conclusion: This study is the first to describe an antimicrobial role for neuropeptides in pulp biology. The antimicrobial actions of neuropeptides contribute a novel aspect to pulpal defence against cariogenic and endodontic bacteria worthy of further investigation.

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Introduction: Human alpha defensins are a family of neutrophil-derived antimicrobial peptides also known as human neutrophil peptides (HNPs). The defensin family of peptides are characterised by six invariant cysteine residues forming three disulphide bridges. The formation of the correct disulphide pairs complicates the synthesis of full length human alpha defensin and limits its therapeutic potential as an antimicrobial peptide. Objectives: The aim of this study was to determine whether truncated alpha defensins displayed antimicrobial activity against a range of micro-organisms including oral pathogens. Methods: Engineered peptides were synthesised by solid-phase methods using standard Fmoc chemistry. Antibacterial assays were performed using a previously described ultra sensitive radial diffusion method. A total of five engineered defensin peptides and full length alpha defensin were tested for their sensitivity against eight micro-organisms, including Gram negative bacteria, Gram positive bacteria and fungal pathogens Results: Antimicrobial activity was identified as clear zones around peptide-containing wells. Zone diameters were used to calculate minimum inhibitory concentrations (MICs) for each peptide. There was considerable variability in the susceptibility of the micro-organisms to the truncated analogues. Bacillus subtilis and Enterococcus faecalis were sensitive to the majority of the engineered peptides whereas Staphylococcus aureus, Escherichia coli and Candida albicans displayed resistance (defined as an MIC of greater than 250 ug/ml) to the truncated defensins. Of the five engineered peptides synthesised, the 2-aminobenzoic acid (Abz)-containing analogues based on the C-terminal sequence of alpha defensin displayed MIC values closest to that of the full length defensin in 5 out of 8 micro-organisms studied. Conclusion: This study demonstrates that truncated alpha defensins display variable antimicrobial activity against a range of micro-organisms, including oral pathogens. The generation of truncated defensins without disulphide bridges simplifies their synthesis and increases their therapeutic potential.

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Background: Epididymal protease inhibitor (eppin) is a dual motif protein belonging to the whey acidic protein (WAP) family. Although expressed in numerous different tissues, to date, its functional characterisation is limited. It has been shown to exhibit antibacterial activity against Gram-negative bacteria (Escherichia coli) and antiprotease activity against some proteases of the serine protease family. We are interested in determining the role of eppin in innate immune defence. Objectives: This study aims to determine eppin's potential function in the innate immune response in the oral cavity by investigating the antimicrobial activity of eppin against relevant oral pathogens. Methods: Eppin was recombinantly expressed in E. coli cells and purified by immobilised metal affinity chromatography (IMAC). The antimicrobial effects of the protein were then assessed against two oral pathogens, Fusobacterium nucleatum and Candida albicans, using a double layer radial diffusion assay. Results: Eppin displayed antimicrobial activities against both oral pathogens tested and these activities were shown to be comparable to the well characterised antimicrobial peptide, LL-37. The antifungal effects of eppin were shown to be more potent than those of the human cathelicidin, LL-37. Conclusions: Eppin has been shown to possess both antibacterial and antifungal properties against oral pathogens, suggesting an important role for this protein in the innate immune response in the oral cavity. This study furthers our knowledge of the physiological role exerted by eppin and its possible role in the modulation of chronic diseases such as periodontitis and oral candidiasis.

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BACKGROUND: Glucagon-like peptide-1 (GLP-1) therapies are routinely used for glycaemic control in diabetes and their emerging cardiovascular actions have been a major recent research focus. In addition to GLP-1 receptor activation, the metabolically-inactive breakdown product, GLP-1(9-36)amide, also appears to exert notable cardiovascular effects, including protection against acute cardiac ischaemia. Here, we specifically studied the influence of GLP-1(9-36)amide on chronic post-myocardial infarction (MI) remodelling, which is a major driver of heart failure progression.

METHODS: Adult female C57BL/6 J mice were subjected to permanent coronary artery ligation or sham surgery prior to continuous infusion with GLP-1(9-36)amide or vehicle control for 4 weeks.

RESULTS: Infarct size was similar between groups with no effect of GLP-1(9-36)amide on MI-induced cardiac hypertrophy, although modest reduction of in vitro phenylephrine-induced H9c2 cardiomyoblast hypertrophy was observed. Whilst echocardiographic systolic dysfunction post-MI remained unchanged, diastolic dysfunction (decreased mitral valve E/A ratio, increased E wave deceleration rate) was improved by GLP-1(9-36)amide treatment. This was associated with modulation of genes related to extracellular matrix turnover (MMP-2, MMP-9, TIMP-2), although interstitial fibrosis and pro-fibrotic gene expression were unaltered by GLP-1(9-36)amide. Cardiac macrophage infiltration was also reduced by GLP-1(9-36)amide together with pro-inflammatory cytokine expression (IL-1β, IL-6, MCP-1), whilst in vitro studies using RAW264.7 macrophages revealed global potentiation of basal pro-inflammatory and tissue protective cytokines (e.g. IL-1β, TNF-α, IL-10, Fizz1) in the presence of GLP-1(9-36)amide versus exendin-4.

CONCLUSIONS: These data suggest that GLP-1(9-36)amide confers selective protection against post-MI remodelling via preferential preservation of diastolic function, most likely due to modulation of infiltrating macrophages, indicating that this often overlooked GLP-1 breakdown product may exert significant actions in this setting which should be considered in the context of GLP-1 therapy in patients with cardiovascular disease.

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The chapter argues that language and cultural communication matter in a transnational world and that the transmission of prejudices against minorities has to be closely analysed while contextualising national histories with minorities. Looking at two spatial sites (Leeds and Warsaw) and analysing interview material that was drawn from a larger study, the authors discuss the way local people address difference particularly through the axes of gendered ethnicity (Muslim men) and gendered class (male underclass). It explores how the same categories of difference are discursively produced in Poland and the UK/ England; to what degree they differ or overlap.

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Acetone was investigated and found to be an appropriate alternative to Triton X-100 as a solvent of essential oils in bioassays aimed to investigate their effects on pinewood nematode (Bursaphelenchus xylophilus) mortality. Therefore it was used as dilution agent to screen the effectiveness of fifty two essential oils against this pest. Thirteen essential oils were highly effective, resulting in more than 90% pinewood nematode mortality at 2 mg/mL, with six of them resulting in 100% mortality. LC100 values ranged between 0.50 mg/mL and 0.83 mg/mL for the essential oils of Origanum vulgare and Satureja montana, respectively. Essential oils were submitted to gas chromatography and gas chromatography-mass spectrometry analysis and their chemical composition established. Data from essential oils with 100% mortality at 2 mg/mL and other essential oils previously found to have LC100 ≤ 2 mg/mL was combined, their chemical profiles investigated by correspondences analysis plus automatic classification.

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The present work has the merit of exploring an insight into the activation of defence genes of Quercus suber during response to infection by Phytophthora cinnamomi. Thus, cDNA-AFLP methodology was used to identify gene fragments differentially present in the mRNA profiles of host cells of micropropagated Q. suber plantlets roots infected with zoospores of P. cinnamomi at different post challenge time points. Six candidate genes were selected based on their interesting cDNA-AFLP expression patterns and homology to genes known to play a role in defence. These six genes encode a cinnamyl alcohol dehydrogenase 2 (QsCAD2), a protein disulphide isomerase (QsPDI), a CC-NBS-LRR resistance protein (QsRPc), thaumatin-like protein (QsTLP), chitinase (QsCHI) and a 1,3-beta glucanase (QsGLU). The current work has been successful in evaluation of the expression of these genes by qRT-PCR. Data analysis revealed that transcript levels of QsRPc, QsCHI, QsCAD2 and QsPDI increased during the early hours of inoculation, while transcript profiles of thaumatin-like protein showed decreasing. No expression was detected for 1,3-beta-glucanase (QsGLU). Furthermore, the choice of suitable reference genes in any new experimental system is absolutely crucial in qRT-PCR; for this reason in this study and for the first time a set of potential reference genes were analyzed and validated for qRT-PCR normalization in the patho-system Phytophthora-Q. suber. Four candidate reference genes polimerase II (QsRPII), eukaryotic translation initiation factor 5A(QsEIF-5A), b-tubulin (QsTUB) and a medium subunit family protein of Clathrin adaptor complexes (QsCACs) were evaluated to determine the most stable internal references in Q. suber. Analysis of stability of genes was carried out using Genex software. Results indicated all these four potential reference genes assumed stable expression. Data analysis revealed that QsRPII and QsCACs were the two most stable genes, while genes QsTUB and QsEIF-5A were the third and the fourth most stable gene, respectively. In this study, a plasmid-based quantitative PCR method was developed to measure P. cinnamomi colonization during infection process of Q. suber. Plasmid-based detection of P. cinnamomi showed a gradual accumulation of the pathogen DNA in cork oak root tips up to 24 h post infection. The higher increase in P. cinnamomi/plasmid DNA ratio occurred between 18 and 24 h. One of the primary objectives of this research was to study the effect of cinnamomins (elicitins secreted by P. cinnamomin) on inducing defence mechanism against the pathogen, as recent histological and ultra-structural studies showed that P. cinnamomi was restricted to the outer cortex root fragments pre-treated with capsicien and cryptogein, suggesting that elicitins can stimulate plant defence reactions against P. cinnamomi. To complement these studies and to have a clear view of the nature of the interaction, the role of cinnamomins in the production of the oxidative burst [ROS and ROS scavenging enzymes such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD)] and in the defence responses was evaluated. Cork oak seedlings were pretreated with alpha-cinnamomin and then inoculated with P. cinnamomi mycelia. Results showed a significant higher production of reactive oxygen species (ROS) (H2O2 and O2•-) in elicitin and non-elicitin treated roots in interaction with P. cinnamomi in comparison to the corresponding control. The plant group inoculated with the pathogen after cinnamomin treatment showed an earlier increase in H2O2 production but this was lower as compared with that group inoculated with P. cinnamomi alone. Also, in elicitin pre-treated group generally, a lower level of O2•− production during infection was observed as compared with inoculated roots with P. cinnamomi alone without elicitin treatment. Furthermore, in this study, we evaluated activities of antioxidant enzymes upon challenge with P. cinnamomi, with and without pretreatment with alpha cinnamomin. Results indicated that the activities of defense enzymes POD, SOD and CAT increased after P. cinnamomi inoculation when compared with those in the control group. Also, in the group treated with alpha-cinnamomin followed by P. cinnamomi inoculation, a higher level of enzymatic activities was detected as compared with elicitin non-treated group, which suggest the protective effect of alpha-cinnamomin against the pathogen due to higher elevated levels of defense enzymes POD, SOD and CAT during the infection period. Furthermore, a sensitive qPCR method was applied to measure the pathogen biomass in elicited and non-elicited Q. suber roots challenged with P. cinnamomi to elucidate the effect of cinnamomins on the colonization of P. cinnamomi. Plasmid-based quantification of P. cinnamomi showed a significant decrease in accumulation of the pathogen DNA in cork oak roots after treatment with alpha and beta-cinnamomins which attest the role of cinnamomins in promoting defense responses in cork oak against P. cinnamomi invasion.

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Tese de doutoramento, Ciências Agrárias (Proteção de Plantas), Faculdade de Ciência e Tecnologia, Universidade do Algarve, 2014