251 research outputs found

    Quantitative estimation of renal blood flow by power Doppler ultrasonography in renovascular hypertensive dogs

    Get PDF
    Quantitative estimation of renal blood flow by power Doppler ultrasonography in renovascular hypertensive dogs.BackgroundWe estimated the value of power Doppler (PD) imaging analysis for the quantitative assessment of renal cortical blood flow (RCBF) in chronic two-kidney, one-clip (2K-1C) hypertensive dogs.MethodsTo evaluate the correlation between RCBF and PD signals, RCBF and the mean pixel intensity (MPI) of PD signals were simultaneously obtained at same region in renal cortex under progressive constriction of left main renal artery in five mongrel dogs. RCBF was measured by electrolytic hydrogen gas clearance method, and PD images were transferred to computer and analyzed by the image-analysis software Openlab®. To assess the value of quantitative PD imaging analysis on RCBF in renovascular hypertension, in six mongrel dogs with chronic 2K-1C hypertension, PD images in both of clipped kidneys (CK) and non-clipped kidneys (NK) were obtained and analyzed before and 60 minutes after the intravenous infusion of captopril or sodium nitroprusside at 10-minute intervals.ResultsThere was a linear correlation between RCBF and MPI (r = 0.878, P < 0.0001). MPI in both CK and NK significantly increased after the infusion of captopril, while no significant change was observed in both CK and NK after the infusion of sodium nitroprusside, despite similar reduction of mean arterial blood pressure.ConclusionOur data suggest that the acute inhibition of angiotensin-converting enzyme increased RCBF in both CK and NK of chronic 2K-1C dogs. The quantitative analysis of PD flow signals in kidney is noninvasive and a useful method to evaluate regional changes of renal tissue blood flow in various renal diseases

    Study of hadron interactions in a lead-emulsion target

    Full text link
    Topological and kinematical characteristics of hadron interactions have been studied using a lead-emulsion target exposed to 2, 4 and 10 GeV/c hadron beams. A total length of 60 m π\pi^- tracks was followed using a high speed automated emulsion scanning system. A total of 318 hadron interaction vertices and their secondary charged particle tracks were reconstructed. Measurement results of interaction lengths, charged particle multiplicity, emission angles and momenta of secondary charged particles are compared with a Monte Carlo simulation and appear to be consistent. Nuclear fragments emitted from interaction vertices were also detected by a newly developed emulsion scanning system with wide-angle acceptance. Their emission angle distributions are in good agreement with the simulated distributions. Probabilities of an event being associated with at least one fragment track are found to be greater than 50% for beam momentum P>4P > 4 GeV/c and are well reproduced by the simulation. These experimental results validate estimation of the background due to hadron interactions in the sample of τ\tau decay candidates in the OPERA νμντ\nu_{\mu} \to \nu_{\tau} oscillation experiment.Comment: 14 pages, 11 figure

    Kheper, a Novel ZFH/δEF1 Family Member, Regulates the Development of the Neuroectoderm of Zebrafish (Danio rerio)

    Get PDF
    AbstractKheper is a novel member of the ZFH (zinc-finger and homeodomain protein)/δEF1 family in zebrafish. kheper transcripts are first detected in the epiblast of the dorsal blastoderm margin at the early gastrula stage and kheper is expressed in nearly all the neuroectoderm at later stages. kheper expression was expanded in noggin RNA-injected embryos and also in swirl mutant embryos and was reduced in bmp4 RNA-injected embryos and chordino mutant embryos, suggesting that kheper acts downstream of the neural inducers Noggin and Chordino. Overexpression of Kheper elicited ectopic expansion of the neuroectoderm-specific genes fkd3, hoxa-1, and eng3, and the ectopic expression of hoxa-1 was not inhibited by BMP4 overexpression. Kheper interacted with the transcriptional corepressors CtBP1 and CtBP2. Overexpression of a Kheper mutant lacking the homeodomain or of a VP16–Kheper fusion protein disturbed the development of the neuroectoderm and head structures. These data underscore the role of Kheper in the development of the neuroectoderm and indicate that Kheper acts as a transcriptional repressor

    The Shigella OspC3 Effector Inhibits Caspase-4, Antagonizes Inflammatory Cell Death, and Promotes Epithelial Infection

    Get PDF
    SummaryCaspase-mediated inflammatory cell death acts as an intrinsic defense mechanism against infection. Bacterial pathogens deploy countermeasures against inflammatory cell death, but the mechanisms by which they do this remain largely unclear. In a screen for Shigella flexneri effectors that regulate cell death during infection, we discovered that Shigella infection induced acute inflammatory, caspase-4-dependent epithelial cell death, which is counteracted by the bacterial OspC3 effector. OspC3 interacts with the caspase-4-p19 subunit and inhibits its activation by preventing caspase-4-p19 and caspase-4-p10 heterodimerization by depositing the conserved OspC3 X1-Y-X2-D-X3 motif at the putative catalytic pocket of caspase-4. Infection of guinea pigs with a Shigella ospC3-deficient mutant resulted in enhanced inflammatory cell death and associated symptoms, correlating with decreased bacterial burdens. Salmonella Typhimurium and enteropathogenic Escherichia coli infection also induced caspase-4-dependent epithelial death. These findings highlight the importance of caspase-4-dependent innate immune responses and demonstrate that Shigella delivers a caspase-4-specific inhibitor to delay epithelial cell death and promote infection

    An Analysis of Essay Examination Data

    Get PDF
    The purpose of this study is to investigate the structure of the data obtained from essay examinations. One set of data was obtained by assigning a small essay test on the title of "Travel" to the 185 10th grade high school students. The essays were evaluated holistically and analytically by the 11 raters, and the 3 raters among them evaluated the same essays repeatedly after more than one week. The orders of the essays were always randomized. Another set of data was obtained by assigning also a small essay test on the title of "Poverty and Richness" to the 144 12th grade girl high school students. The essays were also holistically and analytically evaluated by the other 7 raters (all were teachers), and the 5 raters among them evaluated the same essays after more than two weeks. The main findings were as follows. 1. The consistency of the holistic scores is very low among the raters. 2. The stability of the holistic scores was very different among the raters, and was judged to be low. 3. The 15 viewpoints for the analytic evaluation were classified into the two categories, "content" and "language skills". 4. The first principal component of the scores obtained by the analytic evaluation shows almost the same level of reliability with that of the holistic scores. 5. The high consistency among the raters was observed for the evaluation of the easiness of reading. 6. The close relationship was observed between the holistic evaluation and the general impression of the essays
    corecore