1,716 research outputs found

    On Contending with Unruly Neighbors in the Global Village: Viewing Information Systems as Both Weapon and Target

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    While information technologies we employ in business, government, and society have dramatically enhanced our ability to conduct commerce, the vulnerabilities of these systems create potential dangers not often fully apprehended. As an example, criminal and terrorist groups have demonstrated a sophisticated understanding of how to adapt organizational forms and information technologies to advance their agendas, regardless of how contemptible these may be. In this article, we consider how these groups may view information technology and systems both as means by which they may more effectively organize themselves and as potential targets as they subvert the underlying societal assumptions regarding the technology itself. Topics such as these have implications for both IS research and practice because the changing nature of warfare means entities that may have until recently been seen as “non-combatant” are no longer viewed as such; any organization’s online resources may be regarded and serviced as legitimate targets. This fact, coupled with the interconnectedness of the global economy, makes it imperative to understand the potential threat—whether this is acted on by criminals, terrorists, or even by hostile nation states—and place greater emphasis on defending vital systems against such attacks

    An unusual adrenal cause of hypoglycaemia

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    Cyclic-di-AMP synthesis by the diadenylate cyclase CdaA is modulated by the peptidoglycan biosynthesis enzyme GlmM in lactococcus lactis

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    © 2016 John Wiley & Sons Ltd. The second messenger cyclic-di-adenosine monophosphate (c-di-AMP) plays important roles in growth, virulence, cell wall homeostasis, potassium transport and affects resistance to antibiotics, heat and osmotic stress. Most Firmicutes contain only one c-di-AMP synthesizing diadenylate cyclase (CdaA); however, little is known about signals and effectors controlling CdaA activity and c-di-AMP levels. In this study, a genetic screen was employed to identify components which affect the c-di-AMP level in Lactococcus. We characterized suppressor mutations that restored osmoresistance to spontaneous c-di-AMP phosphodiesterase gdpP mutants, which contain high c-di-AMP levels. Loss-of-function and gain-of-function mutations were identified in the cdaA and gdpP genes, respectively, which led to lower c-di-AMP levels. A mutation was also identified in the phosphoglucosamine mutase gene glmM, which is commonly located within the cdaA operon in bacteria. The glmM I154F mutation resulted in a lowering of the c-di-AMP level and a reduction in the key peptidoglycan precursor UDP-N-acetylglucosamine in L. lactis. C-di-AMP synthesis by CdaA was shown to be inhibited by GlmMI154F more than GlmM and GlmMI154F was found to bind more strongly to CdaA than GlmM. These findings identify GlmM as a c-di-AMP level modulating protein and provide a direct connection between c-di-AMP synthesis and peptidoglycan biosynthesis. c-di-AMP is an essential signalling molecule which affects peptidoglycan homeostasis and resistance against various stressors, however little is known regarding how the c-di-AMP level is regulated in the cell. Here we identify the peptidoglycan biosynthesis enzyme GlmM as a modulator of c-di-AMP synthesis through its regulation of diadenylate cyclase enzyme CdaA activity in Lactococcus lactis

    Human Female Genital Tract Infection by the Obligate Intracellular Bacterium Chlamydia trachomatis Elicits Robust Type 2 Immunity

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    While Chlamydia trachomatis infections are frequently asymptomatic, mechanisms that regulate host response to this intracellular Gram-negative bacterium remain undefined. This investigation thus used peripheral blood mononuclear cells and endometrial tissue from women with or without Chlamydia genital tract infection to better define this response. Initial genome-wide microarray analysis revealed highly elevated expression of matrix metalloproteinase 10 and other molecules characteristic of Type 2 immunity (e.g., fibrosis and wound repair) in Chlamydia-infected tissue. This result was corroborated in flow cytometry and immunohistochemistry studies that showed extant upper genital tract Chlamydia infection was associated with increased co-expression of CD200 receptor and CD206 (markers of alternative macrophage activation) by endometrial macrophages as well as increased expression of GATA-3 (the transcription factor regulating TH2 differentiation) by endometrial CD4+ T cells. Also among women with genital tract Chlamydia infection, peripheral CD3+ CD4+ and CD3+ CD4- cells that proliferated in response to ex vivo stimulation with inactivated chlamydial antigen secreted significantly more interleukin (IL)-4 than tumor necrosis factor, interferon-γ, or IL-17; findings that repeated in T cells isolated from these same women 1 and 4 months after infection had been eradicated. Our results thus newly reveal that genital infection by an obligate intracellular bacterium induces polarization towards Type 2 immunity, including Chlamydia-specific TH2 development. Based on these findings, we now speculate that Type 2 immunity was selected by evolution as the host response to C. trachomatis in the human female genital tract to control infection and minimize immunopathological damage to vital reproductive structures. © 2013 Vicetti Miguel et al

    Helping students to self-care and enhance their health-promotion skills.

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    Nurses have a public health role, requiring them to promote the health of individuals and communities, and to engage at a political and policy level to improve population health. There is also a professional expectation that nurses will model healthy behaviours and take responsibility for their personal health and wellbeing. However, studies have indicated that undergraduate nurses find the academic and practice elements of their nursing programmes stressful. To manage their stress many use coping behaviours that negatively impact on their health and wellbeing and may influence their ability and willingness to effectively support health promotion in practice. It is widely recognised that environments influence health outcomes and personal health behaviours. This article addresses some of the structural causes of student nurse stress and highlights a recent educational initiative at a UK university that aims to equip student nurses with the practical skills required to engage in health promotion and thereby provide benefits for service users and student nurses alike
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