100 research outputs found

    Pentachlorophenol Induction of the Pseudomonas aeruginosa mexAB-oprM Efflux Operon: Involvement of Repressors NalC and MexR and the Antirepressor ArmR

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    Pentachlorophenol (PCP) induced expression of the NalC repressor-regulated PA3720-armR operon and the MexR repressor-controlled mexAB-oprM multidrug efflux operon of Pseudomonas aeruginosa. PCP's induction of PA3720-armR resulted from its direct modulation of NalC, the repressor's binding to PA3720-armR promoter-containing DNA as seen in electromobility shift assays (EMSAs) being obviated in the presence of this agent. The NalC binding site was localized to an inverted repeat (IR) sequence upstream of PA3720-armR and overlapping a promoter region whose transcription start site was mapped. While modulation of MexR by the ArmR anti-repressor explains the upregulation of mexAB-oprM in nalC mutants hyperexpressing PA3720-armR, the induction of mexAB-oprM expression by PCP is not wholly explainable by PCP induction of PA3720-armR and subsequent ArmR modulation of MexR, inasmuch as armR deletion mutants still showed PCP-inducible mexAB-oprM expression. PCP failed, however, to induce mexAB-oprM in a mexR deletion strain, indicating that MexR was required for this, although PCP did not modulate MexR binding to mexAB-oprM promoter-containing DNA in vitro. One possibility is that MexR responds to PCP-generated in vivo effector molecules in controlling mexAB-oprM expression in response to PCP. PCP is an unlikely effector and substrate for NalC and MexAB-OprM - its impact on NalC binding to the PA3720-armR promoter DNA occurred only at high µM levels - suggesting that it mimics an intended phenolic effector/substrate(s). In this regard, plants are an abundant source of phenolic antimicrobial compounds and, so, MexAB-OprM may function to protect P. aeruginosa from plant antimicrobials that it encounters in nature

    From ‘shallow’ to ‘deep’ policing:‘crash-for-cash’ insurance fraud investigation in England and Wales and the need for greater regulation

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    The policing of insurance fraud has traditionally been dealt with beyond the criminal justice system as a private matter between the claimant and the insurer with only a few iconic cases referred to the criminal justice system each year. The growth of insurance fraud, particularly ‘crash-for-cash’ fraud, and the disinterest of the police, has led to a change in the response of the insurance industry. This paper will argue that this response can be characterised as a shift from the traditional ‘shallow’ to a ‘deeper’ form of policing which sees greater focus upon criminal and quasi-criminal outcomes. This paper explores some of the private and innovative methods the industry has developed and illustrates what greater private criminal investigation might look like at a time when police privatisation has become a higher profile issue. The paper argues the shift to ‘deeper’ policing necessitates greater regulation of the private investigation of crime and outlines a number of proposals to address this gap which require further consideration and debate

    Comparative antibacterial potential of selected aldehyde-based biocides and surfactants against planktonic Pseudomonas fluorescens

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    The antimicrobial efficacy of two aldehydebased biocides (glutaraldehyde, GTA, and orthophthalaldehyde, OPA) and two surfactants (cetyltrimethyl ammonium bromide, CTAB, and sodium dodecyl sulphate, SDS) was tested against planktonic Pseudomonas fluorescens. The antimicrobial effects were evaluated by respiratory activity as a measure of the oxygen uptake rate, adenosine triphosphate (ATP) release, outer membrane proteins (OMP) expression and cellular colour changes. The results were compared with the bacterial characteristics without chemical treatment. Tests in the presence of bovine serum albumin (BSA), in order to mimic a disinfection process in the real situation under dirty conditions, were performed according to the European Standard EN-1276. P. fluorescens was completely inactivated with OPA (minimum bactericidal concentration, MBC = 0.5 mM) and CTAB (MBC = 5 mM) and was resistant to GTA and SDS. Only CTAB promoted cellular disruption and consequent ATP release. The antimicrobial action of the chemicals tested was significantly reduced when BSA was introduced into the bacterial cultures, increasing markedly the MBC values. Additionally, the presence of BSA acted as a disruption protective agent when CTAB was applied and stimulated the bacterial respiratory activity when lower concentrations of SDS were tested. The OMP of the bacterial cells was affected by the application of both surfactants. OMP expression remained unaltered after biocide treatment. Bacterial colour change was noticed after treatment with biocides and surfactants. In summary, P. fluorescens was extremely resistant to GTA and SDS, with antimicrobial action being quenched markedly by the reaction with BSA.Instituto de Biotecnologia e Química Fina (IBQF).Fundação para a Ciência e a Tecnologia (FCT) - (Project CHEMBIO - POCI/BIO/61872/2004

    The culture variable vis-à-vis anti-bribery law: a grey area in transnational corporate criminal liability

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    Cross-border transactions are generating corresponding globalisation of law enforcement efforts. Culture has significantly influenced the legal analysis of anti-bribery law. With the increase of transnational bribery, benefits from globalisation will be undermined unless an effective legal regime can mitigate the harm of bribery. It is perceived that corruption in China is more prevalent than in the West given its embedded place in Chinese culture. It is further alleged that Chinese multinational companies (MNCs) are taking advantage of an unlevel playing field, as they are not subject to stringently-enforced anti-bribery laws. This hypothesis creates a myriad of anti-bribery problems in terms of legislation and enforcement, which particularly manifest in China’s perceived cultural toleration of bribery. Cultural assumptions undermine the global anti-bribery regime and compromise potential collaborative anti-bribery efforts across jurisdictions in a rapidly globalizing world. The Chinese culture does not necessarily impede China’s criminalisation of paying bribes to foreign officials. It is argued that the cultural role should not be overestimated, otherwise the hazard of the ethnocentric engagement with the Chinese culture would affect the ability of foreign MNCs to integrate their global compliance programmes. Multinationals can only mitigate their exposure to criminal liability globally, provided that they comply robustly with anti-bribery laws of both home and host jurisdictions

    From ‘shallow’ to ‘deep’ policing: ‘crash-for-cash’ insurance fraud investigation in England and Wales and the need for greater regulation

    Get PDF
    The policing of insurance fraud has traditionally been dealt with beyond the criminal justice system as a private matter between the claimant and the insurer with only a few iconic cases referred to the criminal justice system each year. The growth of insurance fraud, particularly ‘crash-for-cash’ fraud, and the disinterest of the police, has led to a change in the response of the insurance industry. This paper will argue that this response can be characterised as a shift from the traditional ‘shallow’ to a ‘deeper’ form of policing which sees greater focus upon criminal and quasi-criminal outcomes. This paper explores some of the private and innovative methods the industry has developed and illustrates what greater private criminal investigation might look like at a time when police privatisation has become a higher profile issue. The paper argues the shift to ‘deeper’ policing necessitates greater regulation of the private investigation of crime and outlines a number of proposals to address this gap which require further consideration and debate

    Aromatic alcohols and their effect on Gram-negative bacteria, cocci and mycobacteria

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