Preparation and magnetisation of a silica-magnetite inverse ferrofluid

We introduce an ‘inverse ferrofluid’ comprising sterically stabilized, colloidal silica spheres and oleic acid stabilized magnetite particles. The preparation is described as well as magnetisation measurements which turns out to be a linear function of the silica volume fraction

Peroxiredoxin 4, a novel circulating biomarker for oxidative stress and the risk of incident cardiovascular disease and all-cause mortality

BACKGROUND: Oxidative stress has been suggested to play a key role in the development of cardiovascular disease (CVD). The aim of our study was to investigate the associations of serum peroxiredoxin 4 (Prx4), a hydrogen peroxide-degrading peroxidase, with incident CVD and all-cause mortality. We subsequently examined the incremental value of Prx4 for the risk prediction of CVD compared with the Framingham risk score (FRS). METHODS AND RESULTS: We performed Cox regression analyses in 8141 participants without history of CVD (aged 28 to 75 years; women 52.6%) from the Prevention of Renal and Vascular End-stage Disease (PREVEND) study in Groningen, The Netherlands. Serum Prx4 was measured by an immunoluminometric assay in baseline samples. Main outcomes were: (1) incident CVD events or CVD mortality and (2) all-cause mortality during a median follow-up of 10.5 years. In total, 708 participants (7.8%) developed CVD events or CVD mortality, and 517 participants (6.3%) died. Baseline serum Prx4 levels were significantly higher in participants with incident CVD events or CVD mortality and in those who died than in participants who remained free of outcomes (both P<0.001). In multivariable models with adjustment for Framingham risk factors, hazard ratios were 1.16 (95% CI 1.06 to 1.27, P<0.001) for incident CVD events or CVD mortality and 1.17 (95% CI 1.06 to 1.29, P=0.003) for all-cause mortality per doubling of Prx4 levels. After the addition of Prx4 to the FRS, the net reclassification improvement was 2.7% (P=0.01) using 10-year risk categories of CVD. CONCLUSIONS: Elevated serum Prx4 levels are associated with a significantly higher risk of incident CVD events or CVD mortality and all-cause mortality after adjustment for clinical risk factors. The addition of Prx4 to the FRS marginally improved risk prediction of future CVD

Place attachment in deprived neighbourhoods: The impacts of population turnover and social mix

This paper examines the determinants of individual place attachment, focussing in particular on differences between deprived and others neighbourhoods, and on the impacts of population turnover and social mix. It uses a multi-level modelling approach to take account of both individual- and neighbourhood-level determinants. Data are drawn from a large sample government survey, the Citizenship Survey 2005, to which a variety of neighbourhood-level data have been attached. The paper argues that attachment is significantly lower in more deprived neighbourhoods primarily because these areas have weaker social cohesion but that, in other respects, the drivers of attachment are the same. Turnover has modest direct impacts on attachment through its effect on social cohesion. Social mix has very limited impacts on attachment and the effects vary between social groups. In general, higher status or more dominant groups appear less tolerant of social mix

Attenuated cerebrospinal fluid leukocyte count and sepsis in adults with pneumococcal meningitis: a prospective cohort study

BACKGROUND: A low cerebrospinal fluid (CSF) white-blood cell count (WBC) has been identified as an independent risk factor for adverse outcome in adults with bacterial meningitis. Whereas a low CSF WBC indicates the presence of sepsis with early meningitis in patients with meningococcal infections, the relation between CSF WBC and outcome in patients with pneumococcal meningitis is not understood. METHODS: We examined the relation between CSF WBC, bacteraemia and sepsis in a prospective cohort study that included 352 episodes of pneumococcal meningitis, confirmed by CSF culture, occurring in patients aged >16 years. RESULTS: CSF WBC was recorded in 320 of 352 episodes (91%). Median CSF WBC was 2530 per mm(3 )(interquartile range 531–6983 per mm(3)) and 104 patients (33%) had a CSF WBC <1000/mm(3). Patients with a CSF WBC <1000/mm(3 )were more likely to have an unfavourable outcome (defined as a Glasgow Outcome Scale score of 1–4) than those with a higher WBC (74 of 104 [71%] vs. 87 of 216 [43%]; P < 0.001). CSF WBC was significantly associated with blood WBC (Spearman's test 0.29), CSF protein level (0.20), thrombocyte count (0.21), erythrocyte sedimentation rate (-0.15), and C-reactive protein levels (-0.18). Patients with a CSF WBC <1000/mm(3 )more often had a positive blood culture (72 of 84 [86%] vs. 138 of 196 [70%]; P = 0.01) and more often developed systemic complications (cardiorespiratory failure, sepsis) than those with a higher WBC (53 of 104 [51%] vs. 69 of 216 [32%]; P = 0.001). In a multivariate analysis, advanced age (Odds ratio per 10-year increments 1.22, 95%CI 1.02–1.45), a positive blood culture (Odds ratio 2.46, 95%CI 1.17–5.14), and a low thrombocyte count on admission (Odds ratio per 100,000/mm(3 )increments 0.67, 95% CI 0.47–0.97) were associated with a CSF WBC <1000/mm(3). CONCLUSION: A low CSF WBC in adults with pneumococcal meningitis is related to the presence of signs of sepsis and systemic complications. Invasive pneumococcal infections should possibly be regarded as a continuum from meningitis to sepsis

Effects of urinary cortisol levels and resting heart rate on the risk for fatal and nonfatal cardiovascular events

AbstractBackground and aimsHigher cortisol levels are associated with cardiovascular mortality in the elderly. It is unclear whether this association also exists in a general population of younger adults and for non-fatal cardiovascular events. Likewise, resting heart rate is associated with cardiovascular mortality, but fewer studies have also considered non-fatal events. The goal of this study was to investigate whether twenty-four-hour urinary cortisol (24-h UFC) levels and resting heart rate (RHR) predict major adverse fatal and non-fatal cardiovascular events (MACE) in the general population.MethodsWe used data from a subcohort of the PREVEND study, a prospective general population based cohort study with a follow-up of 6.4 years for 24-h UFC and 10.6 years for RHR. Participants were 3432 adults (mean age 49 years, range 28–75). 24-h UFC was collected and measured by liquid chromatography—tandem mass spectrometry. RHR was measured at baseline in a supine position for 10 min with the Dinamap XL Model 9300. Information about cardiovascular events and mortality was obtained from the Dutch national registry of hospital discharge diagnoses and the municipal register respectively.Results24-h UFC did not significantly increase the hazard of MACE (hazard ratio = 0.999, 95% confidence interval = 0.993–1.006, p = 0.814). RHR increased the risk for MACE with 17% per 10 extra heart beats per minute (hazard ratio = 1.016, 95% confidence interval = 1.001–1.031, p = 0.036) after adjustment for conventional risk factors.ConclusionsIn contrast to 24-h UFC, RHR is a risk marker for MACE in the general population