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Background: Haemoglobin (Hb) variants are well-known factors interfering with accurate HbA1c testing. This report describes two novel Hb variants leading to inappropriate quantification of HbA1c by ion-exchange chromatography. Methods: Glycated forms of novel Hb variants were recognised in the blood of two patients with diabetes mellitus screened by HbA1c ion-exchange chromatography. Dedicated high-resolution cation-exchange chromatography and subsequent DNA sequencing revealed the exact nature of the variants. Other common techniques for quantifying HbA1c were applied on both samples and haematological parameters were determined to judge possible pathology associated with the novel Hb variants. Results: A fraction of 15% of abnormal Hb was observed in a 37-year-old female. DNA sequencing revealed a heterozygous mutation in the α1-globin gene, resulting in a leucine-to-phenylalanine amino-acid substitution (HBA1: c.301C > T, p.Leu101Phe). We named this variant Hb Weesp. The other novel variant, Hb Haelen, presented as a 40% fraction in a 63-year-old male and resulted from a heterozygous amino acid substitution in the β-globin gene (HBB: c.335T > C, p.Val112Gly). The presence of both Hb variants resulted in aberrant separation of the Hb components, leading to an inadequate quantification of HbA1c. Conclusions: Close examination of HbA1c chromatograms revealed two novel, clinically silent Hb variants that interfere with HbA1c quantification. Healthcare providers need to be aware of the potential of such Hb variants when interpreting HbA1c results. [ABSTRACT FROM AUTHOR]

Abstract: Radiation-induced displacement damage, which has caused the increase of the dark current in the focal plane adopted in the Ozone Monitoring Instrument (OMI), was studied in regards of the primary protons and the secondaries generated by the protons in the orbit. Using the Monte Carlo N-Particle Transport Code System (MCNPX) version 2.4.0 along with the Stopping and Range of Ions in Matter version 2010 (SRIM2010), effects of the primary protons as well as secondary particles, including neutron, electron, and photon were investigated. After their doses and fluxes that reached onto the charge-coupled device (CCD) were examined, displacement damage induced by major sources was presented. [Copyright &y& Elsevier]

Tacrolimus, an immunosuppressant used after organ transplantation, has a narrow therapeutic range and its pharmacokinetic variability complicates its daily dose assessment. P-glycoprotein (P-gp), encoded by the adenosine triphosphate-binding cassette B1 ( ABCB1) and the cytochrome ( CYP) 3A4 and 3A5 enzymes appears to play a role in the tacrolimus metabolism. In the present study, two different renal transplant recipient groups were used to examine the influence of ABCB1 and CYP3A polymorphisms on the daily tacrolimus dose and several pharmacokinetic parameters. In total 63 Caucasian renal transplant recipients divided into 26 early [median (range) of the days since transplantation – 16 (3–74)] and 37 late [median (range) of the days since transplantation – 1465 (453–4128)] post-transplant recipients were genotyped for ABCB1 and CYP3A polymorphisms. The pharmacokinetic parameters of tacrolimus were determined for all renal transplant recipients and correlated with their corresponding genotypes. A significant difference in allele frequencies of the CYP3A4*1B ( P = 0.028) and CYP3A5*1 ( P = 0.022) alleles was observed between the early and late post-transplant recipient groups. Significantly higher dose-normalized trough levels (dn C0), dose-normalized area under the curve (dnAUC0−12), and dose-normalized maximum concentration (dn Cmax) were observed for carriers of the CYP3A5*3 variant allele in both renal transplant patient groups. Except for the daily tacrolimus dose ( P = 0.025) no significant differences were observed for carriers of the CYP3A4*1B variant allele. Neither the individual ABCB1 polymorphisms nor the ABCB1 haplotypes were associated with any pharmacokinetic parameter. We noticed that patients carrying a CYP3A5*1 allele require a twofold higher tacrolimus dose compared with homozygous carriers of the CYP3A5*3 variant allele to maintain the target dnAUC0−12. Therefore, genotyping for the CYP3A5*3 variant allele can contribute to a better and more individualized immunosuppressive therapy in transplant patients. [ABSTRACT FROM AUTHOR]

The Ozone Monitoring Instrument (OMI) was launched on July 15, 2004 on the National Aeronautics and Space Administration's Earth Observing System Aura satellite. OMI is an ultraviolet-visible imaging spectrograph providing daily global coverage with high spatial resolution. This paper discusses the ground data processing software used for Level 0 to Level lb processing of OMI data. In addition, the OMI operations scenario is described together with the data processing concept. This paper is intended to serve as a reference guide for users of OMI (Level 1b) data. [ABSTRACT FROM AUTHOR]

The Ozone Monitoring Instrument (OMI) was launched on July 15, 2004 on the National Aeronautics and Space Administration's Earth Observing System Aura satellite. The OMI instrument is an ultraviolet-visible imaging spectrograph that uses two-dimensional charge-coupled device detectors to register both the spectrum and the swath perpendicular to the flight direction with a 115° wide swath, which enables global daily ground coverage with high spatial resolution. This paper presents the OMI design and discusses the main performance and calibration features and results. [ABSTRACT FROM AUTHOR]

The Ozone Monitoring Instrument (OMI) flies on the National Aeronautics and Space Adminsitration's Earth Observing System Aura satellite launched in July 2004. OMI is a ultraviolet/visible (UV/VIS) nadir solar backscatter spectrometer, which provides nearly global coverage in one day with a spatial resolution of 13 km × 24 km. Trace gases measured include O3, NO2, SO2, HCHO, BrO, and OClO. In addition, OMI will measure aerosol characteristics, cloud top heights, and UV irradiance at the surface. OMI's unique capabilities for measuring important trace gases with a small footprint and daily global coverage will be a major contribution to our understanding of stratospheric and tropospheric chemistry and climate change. OMI's high spatial resolution is unprecedented and will enable detection of air pollution on urban scale resolution. In this paper, the instrument and its performance will be discussed. [ABSTRACT FROM AUTHOR]