299 research outputs found

    Generation of cardio-protective antibodies after pneumococcal polysaccharide vaccine: Early results from a randomised controlled trial.

    Full text link
    BACKGROUND AND AIMS: Observational studies have demonstrated that the pneumococcal polysaccharide vaccine (PPV) is associated with reduced risk of cardiovascular events. This may be mediated through IgM antibodies to OxLDL, which have previously been associated with cardioprotective effects. The Australian Study for the Prevention through Immunisation of Cardiovascular Events (AUSPICE) is a double-blind, randomised controlled trial (RCT) of PPV in preventing ischaemic events. Participants received PPV or placebo once at baseline and are being followed-up for incident fatal and non-fatal myocardial infarction or stroke over 6 years. METHODS: A subgroup of participants at one centre (Canberra; n = 1,001) were evaluated at 1 month and 2 years post immunisation for changes in surrogate markers of atherosclerosis, as pre-specified secondary outcomes: high-sensitive C-reactive protein (CRP), pulse wave velocity (PWV), and carotid intima-media thickness (CIMT). In addition, 100 participants were randomly selected in each of the intervention and control groups for measurement of anti-pneumococcal antibodies (IgG, IgG2, IgM) as well as anti-OxLDL antibodies (IgG and IgM to CuOxLDL, MDA-LDL, and PC-KLH). RESULTS: Concentrations of anti-pneumococcal IgG and IgG2 increased and remained high at 2 years in the PPV group compared to the placebo group, while IgM increased and then declined, but remained detectable, at 2 years. There were statistically significant increases in all anti-OxLDL IgM antibodies at 1 month, which were no longer detectable at 2 years; there was no increase in anti-OxLDL IgG antibodies. There were no significant changes in CRP, PWV or CIMT between the treatment groups at the 2-year follow-up. CONCLUSIONS: PPV engenders a long-lasting increase in anti-pneumococcal IgG, and to a lesser extent, IgM titres, as well as a transient increase in anti-OxLDL IgM antibodies. However, there were no detectable changes in surrogate markers of atherosclerosis at the 2-year follow-up. Long-term, prospective follow-up of clinical outcomes is continuing to assess if PPV reduces CVD events

    Long-term vitamin E supplementation fails to reduce lipid peroxidation in people at cardiovascular risk: analysis of underlying factors

    Get PDF
    BACKGROUND: Antioxidant supplementation with vitamin E had no effect in the prevention of cardiovascular diseases (CVD) in three recent large, randomized clinical trials. In order to reassess critically the role of vitamin E in CVD prevention, it is important to establish whether these results are related to a lack of antioxidant action. METHODS: We examined the in vivo antioxidant effect of vitamin E (300 mg/day for about three years) in 144 participants in the Primary Prevention Project (females and males, aged ≥ 50 y, with at least one major CV risk factor, but no history of CVD). Urinary 8-epi-PGF(2α) (isoprostane F(2α)-III or 15-F(2t)-isoP), a validated biomarker of lipid peroxidation, was measured by mass spectrometry. RESULTS: Urinary excretion of 8-epi-PGF(2α) [pg/mg creatinine, median (range)] was 141 (67–498) in treated and 148 (76–561) in untreated subjects (p = 0.10). Taking into account possible confounding variables, multiple regression analysis confirmed that vitamin E had no significant effect on this biomarker. Levels of 8-epi-PGF(2α) were in the normal range for most subjects, except smokers and those with uncontrolled blood pressure or hyperglycemia. CONCLUSIONS: Prolonged vitamin E supplementation did not reduce lipid peroxidation in subjects with major cardiovascular risk factors. The observation that the rate of lipid peroxidation was near normal in a large proportion of subjects may help explain why vitamin E was not effective as an antioxidant in the PPP study and was ineffective for CVD prevention in large scale trials

    Inhibition of Intestinal Bile Acid Transporter Slc10a2 Improves Triglyceride Metabolism and Normalizes Elevated Plasma Glucose Levels in Mice

    Get PDF
    Interruption of the enterohepatic circulation of bile acids increases cholesterol catabolism, thereby stimulating hepatic cholesterol synthesis from acetate. We hypothesized that such treatment should lower the hepatic acetate pool which may alter triglyceride and glucose metabolism. We explored this using mice deficient of the ileal sodium-dependent BA transporter (Slc10a2) and ob/ob mice treated with a specific inhibitor of Slc10a2. Plasma TG levels were reduced in Slc10a2-deficient mice, and when challenged with a sucrose-rich diet, they displayed a reduced response in hepatic TG production as observed from the mRNA levels of several key enzymes in fatty acid synthesis. This effect was paralleled by a diminished induction of mature sterol regulatory element-binding protein 1c (Srebp1c). Unexpectedly, the SR-diet induced intestinal fibroblast growth factor (FGF) 15 mRNA and normalized bile acid synthesis in Slc10a2−/− mice. Pharmacologic inhibition of Slc10a2 in diabetic ob/ob mice reduced serum glucose, insulin and TGs, as well as hepatic mRNA levels of Srebp1c and its target genes. These responses are contrary to those reported following treatment of mice with a bile acid binding resin. Moreover, when key metabolic signal transduction pathways in the liver were investigated, those of Mek1/2 - Erk1/2 and Akt were blunted after treatment of ob/ob mice with the Slc10a2 inhibitor. It is concluded that abrogation of Slc10a2 reduces hepatic Srebp1c activity and serum TGs, and in the diabetic ob/ob model it also reduces glucose and insulin levels. Hence, targeting of Slc10a2 may be a promising strategy to treat hypertriglyceridemia and diabetes

    Defects in Regulation of Local Immune Responses Resulting in Atherosclerosis

    Get PDF
    Atherosclerosis is nowadays generally accepted as an inflammatory disease but the mechanism of its origin and development have not yet been fully clarified. The present review focuses on the role of the local immune system as one of the key players in the pathogenesis of the complex process. Its part represented by vascular-associated lymphoid tissue (VALT) within the arterial wall participates directly in the vascular wall's homeostatis. Its inordinate activation during ontogenic development of an individual, this formerly defensive and physiologic mechanism transform into a pathological process resulting in an impairing inflammation. Hsp60, CRP and oxidized or otherwise modified LDL are serious candidates for triggering these pathological changes. The principal role is played by anti-Hsp60 antibodies and by shear stress originating on the surface of endothelium due to blood flow. The experimental and clinical data supporting this immunological hypothesis of atherosclerosis are discussed

    The Achene Mucilage Hydrated in Desert Dew Assists Seed Cells in Maintaining DNA Integrity: Adaptive Strategy of Desert Plant Artemisia sphaerocephala

    Get PDF
    Despite proposed ecological importance of mucilage in seed dispersal, germination and seedling establishment, little is known about the role of mucilage in seed pre-germination processes. Here we investigated the role of mucilage in assisting achene cells to repair DNA damage during dew deposition in the desert. Artemisia sphaerocephala achenes were first treated γ-irradiation to induce DNA damage, and then they were repaired in situ in the desert dew. Dew deposition duration can be as long as 421 min in early mornings. Intact achenes absorbed more water than demucilaged achenes during dew deposition and also carried water for longer time following sunrise. After 4-d dew treatment, DNA damage of irradiated intact and demucilaged achenes was reduced to 24.38% and 46.84%, respectively. The irradiated intact achenes exhibited much higher DNA repair ratio than irradiated demucilaged achenes. Irradiated intact achenes showed an improved germination and decreased nonviable achenes after dew treatment, and significant differences in viability between the two types of achenes were detected after 1020 min of dew treatment. Achene mucilage presumably plays an ecologically important role in the life cycle of A. sphaerocephala by aiding DNA repair of achene cells in genomic-stressful habitats

    Proposal, project, practice, pause: developing a framework for evaluating smart domestic product engagement

    Get PDF
    Smart homes are fast becoming a reality, with smart TVs, smart meters and other such “smart” devices/systems already representing a substantial household presence. These, which we collectively term “smart domestic products” (SDPs), will need to be promoted, adopted, and normalized into daily routines. Despite this, the marketing canon lacks a substantive discourse on pertinent research. We look to help correct this by melding ideas from organizational sociology, innovation diffusion and appropriation studies, and service dominant logic. Consequently, we suggest a framework for research that responds directly to the specific characteristics of SDPs. Using the SDP eco-system as a context, our framework emphasizes the interplay of embeddedness, practice, value and engagement. It comprises a four-stage horizontal/ longitudinal axis we describe as proposal, project, practice and pause. Cross-sectionally we focus on value, and combine aspects of existing thought to suggest how this impacts each stage of our engagement continuum. We subsequently identify perceived personal advantage as the resultant of these two axes and propose this as the key for understanding consumer and SDP sociomaterial engagement. This article also advances a definition of SDPs and ends with an agenda for further research

    Postprandial lipemic and inflammatory responses to high-fat meals: a review of the roles of acute and chronic exercise

    Full text link
    corecore