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An analytical method based on liquid chromatography with positive ion electrospray ionization (ESI) coupled to tandem mass spectrometry detection was developed for the determination of lansoprazole in human plasma using omeprazole as the internal standard. The analyte and internal standard were extracted from the plasma samples by liquid-liquid extraction using diethyl-ether-dichloromethane (70:30; v / v) and chromatographed on a C analytical column. The mobile phase 18 consisted of acetonitrile-water (90:10; v / v)110 mM formic acid. The method has a chromatographic total run time of 5 min and was linear within the range 2.5-2000 ng / ml. Detection was carried out on a Micromass triple quadrupole tandem mass spectrometer by Multiple Reaction Monitoring (MRM). The intra-and inter-run precision, calculated from quality control (QC) samples, was less than 3.4%. The accuracy as determined from QC samples was less than 9%. The method herein described was employed in a bioequivalence study of two capsule formulations of lansoprazole. 

Objective: The present study investigated the effect of 2 different lumbar spine postures, neutral and flexed lumbar postures, on transversus abdominis (TrA) muscle function during a voluntary contraction (hollowing and draw-in maneuver) in people with and without low back pain (LBP). Methods: Thirty participants with LBP and 30 healthy participants were recruited for this cross-sectional study. Transversus abdominis muscle function was measured as a change in thickness with ultrasound imaging. Participants performed voluntary TrA contraction in a supine lying position with the lumbar spine in neutral and flexed postures. Data were analyzed using a 2-way (groups, postures) analysis of variance. Results: Lumbar posture influenced TrA function during a voluntary contraction in people with and without LBP. There was a significant main effect of posture (F 1,58 = 16.140, P b .001). Neutral lumbar posture improved participants' ability to recruit TrA in both group (mean difference, 7.5%; 95% confidence interval, 3.8%-11.3%). No significant differences were found between healthy subjects and those with LBP.

Rehabilitative ultrasound imaging has a great potential to be used as a tool in the assessment of trunk muscle function in patients with low back pain (LBP). However, a further investigation of the discriminative ability of this tool as well as the effect of operators' levels of training on reliability is warranted.

Objective: This study evaluated the reliability and discriminatory capacity of a novel clinical scale for assessing abdominal muscle coordination. We investigated the interrater reliability of this tool in patients with chronic low back pain (LBP) (reliability section); the ability of this tool to discriminate healthy and LBP subjects (discriminatory section); and the association between the score and measures of pain, disability, and kinesiophobia (correlation section). Methods: For the reliability section of this study, 14 patients with chronic LBP were included. For the discriminatory section, 10 patients with chronic LBP and 10 pain-free controls were recruited. In the correlation study, data from the 10 chronic LBP patients in the discriminatory section were used. The clinical test was conducted by a blinded examiner while the subjects attempted to independently activate transversus abdominis separate from the rest of the abdominal muscles (hollowing or draw-in maneuver). The intraclass correlation coefficients, receiver operating characteristic curve, and Pearson r correlation coefficients were calculated to assess reliability and validity. Results: An intraclass correlation coefficient (2,1) of 0.72 (95% confidence interval, 0.33-0.90) was recorded for interrater reliability. The tool correctly identified the subject condition in 97% of the cases. The score did not correlate substantially with any clinical measures, with Pearson r ranging from 0.122 (P = .737) to 0.493 (P = .148).

This study investigated the effect of lumbar posture on function of transversus abdominis (TrA) and obliquus internus (OI) in people with and without non-specific low back pain (LBP) during a lower limb task. Rehabilitative ultrasound was used to measure thickness change of TrA and OI during a lower limb task that challenged the stability of the spine. Measures were taken in supine in neutral and flexed lumbar postures in 30 patients and 30 healthy subjects. Data were analysed using a two-way (groups, postures) ANOVA. Our results showed that lumbar posture influenced percent thickness change of the TRA muscle but not for OI. An interaction between group and posture was found for TrA thickness change (F 1,56 ¼ 6.818, p ¼ 0.012). For this muscle, only healthy participants showed greater thickness change with neutral posture compared to flexed (mean difference ¼ 6.2%; 95% CI: 3.1e9.3%; p < 0.001). Comparisons between groups for both muscles were not significant. Neutral lumbar posture can facilitate an increase in thickness of the TrA muscle while performing a leg task, however this effect was not observed for this muscle in patients with LBP. No significant difference in TrA and OI thickness change between people with and without non-specific LBP was found.

Technical reports on operations and features of the Pierre Auger Observatory, including ongoing and planned enhancements and the status of the future northern hemisphere portion of the Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009.

The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies $E>E_{th}=5.5\times 10^{19}$ eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at $E>E_{th}$ are heavy nuclei with charge $Z$, the proton component of the sources should lead to excesses in the same regions at energies $E/Z$. We here report the lack of anisotropies in these directions at energies above $E_{th}/Z$ (for illustrative values of $Z=6,\ 13,\ 26$). If the anisotropies above $E_{th}$ are due to nuclei with charge $Z$, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

The dolastane diterpenes 4-acetoxy-9,14-dihydroxydolast-1(15),7-diene (1) and 4,7-diacetoxy-14-hydroxydolast-1(15),8-diene (2) were isolated from specimens of the alga Dictyota cervicornis collected from the Rio de Janeiro coast, Brazil. Chemical structures of the diterpenes were assigned by 1D and 2D NMR spectral data for the first time. Both substances inhibited Na+K+-ATPase preparations from guinea-pig brain or kidney, with the same inhibitory potency towards enzyme isoforms. The maximal inhibition obtained for 1 was 40% at a concentration of 0.5 mm in the incubation mixture, while it reached 80% for compound 2 at this concentration. Ouabain insensitive ATPases were inhibited by 1, but not by 2. Data comparing the inhibitory potency of these compounds with that of ouabain and oleic acid suggest a higher degree of selectivity of 2 towards the Na+K+-pump. Cardiac glycosides such as ouabain are used classically in the treatment of heart failure, but alterations of Na+K+-pump activity are also involved in several other diseases. Therefore, the study of compounds interfering with this pump activity is gaining further importance. Copyright © 2009 John Wiley & Sons, Ltd.