Portable laser-heating stand for synchrotron applications

A compact, double-sided laser-heating system for diamond-cell synchrotron applications is described. The optical table, containing laser, spectrometer, and all optics for visual observation and measuring temperatures and pressures has an area of less than 1 2 m2 and weighs less than 20 kg. All components can be remotely controlled at micron levels with simple dc motors and pneumatic drives. The design allows quick alignment of the laser-heated hot spot with the x-ray beam and the spectrometer. The prealigned system can be set up at most synchrotron beamlines within about 1 h. We carried out measurements on a variety of materials above one megabar and up to over 4000 K at both the x-ray diffraction beamline ID 27 and the x-ray absorption beamline ID 24 at the European Synchrotron Facility. A new measurement of the melting temperature of iron by x-ray absorption spectroscopy is presented

Responsivity and Reproducibility of Sputum Inflammatory Biomarkers During COPD Exacerbation and Stable Phases - A Pilot Study

Introduction: There is a great interest to identify airway biomarkers to evaluate the potential and efficacy of anti-inflammatory therapeutic interventions. In this pilot study, we compared cytokine mRNA and protein levels of IL-6, IL-8, CCL2, CCL4, and TNF-α, as well as LTB-4 expression regarding their reproducibility and responsivity in induced sputum in COPD patients. Methods: We recruited a cohort of 17 patients with a moderate COPD exacerbation, necessitating antibiotics and/or oral corticosteroids. Patients were followed for two consecutive stable phase visits. Cytokine mRNA and protein levels were measured in induced sputum samples. Results: IL-6 and CCL4 protein levels decreased from exacerbation to stable phase, whereas their mRNA expression showed the same trend (not statistically significant). Coefficients of variation were overall lower (ie, more favorable for responsiveness) at protein levels compared to mRNA levels. No significant differences were observed in the reproducibility between cytokine mRNA expression and protein measurements. IL-6, IL-8, CCL2, and TNF-α gene expression levels yielded moderate to high intraclass correlation coefficients and/or Spearman correlation coefficients between both stable phase samples in contrast to their protein levels. Conclusion: Our findings suggest that several protein levels yield better responsivity with lower noise-to-signal ratios compared to their respective mRNA levels. In contrast, cytokine mRNA expression was more reproducible as it varied less in a stable state than proteins. Future studies are needed with a larger sample size to further evaluate the differences of responsivity and reproducibility between cytokine mRNA and protein measurements, not only during exacerbations

Nachweis und Bestimmung der Halogensauerstoffverbindungen

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