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Background Allergens from rats, mice, guinea pigs or rabbits cause up to 30% of exposed persons to develop specific immunoglobulin E (IgE) responses. Laboratory animal allergy (LAA) is among the highest occupational risks for asthma in the UK. Elevated levels of nitric oxide (NO) are found in exhaled breath in asthma. In LAA symptoms may progress from conjunctivitis, rhinitis to asthma. Health surveillance aims to detect early sensitization. Objective To assess whether an association exists between LAA and exhaled NO. Methods A cross‐sectional study was performed in 39 laboratory workers undergoing LAA health surveillance. Volunteers completed two health questionnaires, had skin‐prick tests, spirometry, total IgE and RAST tests. Exhaled and nasal NO was measured by chemiluminescence analyser (LR2000, Logan Research, Rochester, UK). Results There were 23 asymptomatic subjects (mean age 29.53 yearss) and 16 symptomatic subjects (29.63 yearss, P = 0.95); 9 early LAA, seven LAA asthma. Exhaled NO was raised in those with LAA symptoms 17.97 ppb ± 1.24 (mean ± SEM ) compared with asymptomatics 6.08 ppb ± 1.15, P < 0.05. A trend of increased NO by allergic status was observed; asymptomatic, to early LAA, to asthma. One‐way analysis of variance compared differences between groups (F ratio 13.93, P < 0.001). Symptomatic subjects also had raised nasal NO, vs asymptomatic subjects (mean difference 378 ppb, P < 0.05). A trend was again observed by allergic status (F ratio 5.28, P = 0.01). Conclusion Raised NO levels in LAA increasing with symptom severity suggest NO may prove a useful additional tool in monitoring for LAA, and possibly the response to exposure reduction or allergy due to other respiratory sensitizers.

No abstract is provided for this article.

Introduction: Among super-resolved microscopy (SRM) methods, single molecule localisation microscopy techniques, such as photo-activated localisation microscopy (PALM) [l] and stochastic optical reconstruction microscopy (STORM) [2], enable imaging beyond the classical diffraction limit to gain new insights in subcellular biological processes with relatively simple instrumentation. This has led to a number of low-cost instruments, e.g. for STORM microscopy [3-6], which can benefit from an array of software tools for the single molecule localisation microscopy (SMLM) data analysis [7]. Our low-cost “easySTORM approach [4] implements dSTORM [8] with multimode diode lasers and optical fibres to provide STORM images with fields of view up to ~125 μm diameter using μManager [9] to control the image data acquisition and ThunderSTORM [10] to analyse the SMLM data. We and others [11,12] are motivated to develop automated SMLM for high content analysis (HCA) that enable rapid imaging of sample arrays, allows statistical analysis of samples that may vary in terms of labelling and biological heterogeneity and enable moderate throughput screening applications.

No abstract is provided for this article.

Epicardial marker motion was measured in 14 patients before flecainide administration, immediately after an intravenous dose of 2 mg/kg over 15 minutes (maximum 150 mg) and 15 minutes thereafter. Platinum epicardial markers had been implanted more than 4 years earlier at the time of coronary artery bypass grafting. Maximal and minimal marker separation (Lmax and Lmin) during the cardiac cycle were measured and regional shortening fraction (Lmax — Lmin)/Lmax) was determined as a percentage. After intravenous flecainide, a significant increase in end-diastolic (immediately after 2.8%; after 15 minutes 2.1%) and end-systolic (3.6% and 3.2%) regional dimensions was observed, together with a decrease in regional myocardial shortening (9.3% and 9.0%). One week later, after a single oral dose of 200 mg of flecainide, Lmax and Lmin had increased 2.4% and 2.7%, while regional myocardial shortening did not differ significantly from baseline values. In 10 patients measurements were repeated after 6 weeks of chronic oral treatment with 300 mg/day. Despite plasma flecainide levels similar to those after intravenous administration, no significant changes in end-diastolic and end-systolic dimensions or regional shortening fraction were observed. Thus, acute intravenous or oral flecainide administration increases regional end-diastolic and end-systolic dimensions, but only intravenous administration decreases regional shortening fraction. Values during chronic administration indicate that regional myocardial function is more affected at the time of rising or acutely changing flecainide plasma levels than when stable plasma levels are achieved.

An unstable lesion may rupture and cause an acute thrombotic reaction. These lesions contain a large lipid pool covered by a thin fibrous cap. The stress in the cap increased with decreasing thickness and increasing macrophage infiltration. Intravascular ultrasound (IVUS) elastography might be an ideal technique to assess the presence of lipid pools and identify high stress regions. Elastography assesses the local mechanical properties of tissue using its deformation caused by the intraluminal pressure. The technique was validated in vitro using diseased human coronary and femoral arteries. These experiments demonstrated that the strain in the three plaque types is different (P < 0.001) . Especially between fibrous and fatty tissue, a highly significant difference (P = 0.0012) was found. Additionally, the predictive value for identifying the vulnerable plaque was investigated. A high strain region at the lumen vessel wall boundary has 88% sensitivity and 89% specificity for identifying these plaques. In vivo, the technique is validated in an atherosclerotic Yucatan mini‐pig animal model. This study also revealed higher strain values in fatty than fibrous plaques (P < 0.001) . The presence of a high strain region at the lumen plaque interface has a high predictive value for identifying macrophages. Patient studies revealed high strain values (1–2%) in soft plaques. Calcified material shows low strain values (0–0.2%). With the development of three‐dimensional elastography, identification of weak spots over the full length of a coronary artery becomes possible. In conclusion, intravascular elastography is a unique tool to assess lesion composition and vulnerability. The development of three‐dimensional elastography provides a technique that may develop into a clinical available tool for identifying the rupture‐prone plaque. (J Interven Cardiol 2003;16:253–259)

<h3>Background</h3> Metabolomics could provide new insights into the pathophysiology of cystic fibrosis (CF) by identifying profiles of endogenous metabolites. <h3>Objectives</h3> To investigate whether metabolomics of exhaled breath condensate could discriminate between patients with unstable CF, stable CF and healthy subjects, and whether selected metabolites were responsible for between-group differences. <h3>Methods</h3> Twenty-nine patients with stable CF, 24 with unstable CF and 31 healthy subjects (age 9–24 years) participated in a cross-sectional study. Metabolomics was performed with high-resolution nuclear magnetic resonance spectroscopy. Partial least squares-discriminant analysis was used as classifier. The results were validated in a second independent study. <h3>Results</h3> Intraclass correlation coefficients for between-day and technical repeatability were 0.93 and 0.96, respectively. Bland–Altman analysis showed good within-day repeatability. Correct classification rate of CF (n=53) vs healthy subjects (n=31) was 96% (R²=0.84; Q²=0.79). Model validation with a testing sample set obtained from subjects not included in the primary analysis (23 CF and 25 healthy subjects) showed a sensitivity of 91% and a specificity of 96%. The classification rate of stable CF (n=29) vs unstable CF patients (n=24) was 95% (R²=0.82; Q²=0.78). Model external validation in 14 patients with stable CF and 16 with unstable CF showed a sensitivity of 86% and a specificity of 94%. Ethanol, acetate, 2-propanol and acetone were most discriminant between patients with CF and healthy subjects, whereas acetate, ethanol, 2-propanol and methanol were the most important metabolites for discriminating between patients with stable and unstable CF. <h3>Conclusions</h3> Nuclear magnetic resonance spectroscopy of exhaled breath condensate is reproducible, discriminates patients with CF from healthy subjects and patients with unstable CF from those with stable CF, and identifies the metabolites responsible for between-group differences.