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101.
Muddassir Mehmood Stephanie A. Ambach Michael D. Taylor John L. Jefferies Subha V. Raman Robin J. Taylor Hemant Sawani Jacob Mathew Wojciech Mazur Kan N. Hor Hussein R. Al-Khalidi 《Pediatric cardiology》2016,37(5):878-883
The relationship between pulmonary function and right ventricle (RV) in Duchenne muscular dystrophy (DMD) has not been evaluated. Using cardiac magnetic resonance (CMR), we describe the relationship of RV size and function with spirometry in a DMD cohort. Fifty-seven boys undergoing CMR and pulmonary function testing within 1 month at a single center (2013–2015) were enrolled. Comparisons of RV ejection fraction (RVEF) and end-diastolic volume index (RVEDVI) were made across categories of percent forced vital capacity (FVC%), and relationships were assessed. Mean age was 15.5 ± 3.5 years. Spirometry and CMR were performed within 3.9 ± 4.1 days. Median FVC% was 92.0 % (67.5–116.5 %). Twenty-three (40 %) patients had abnormal FVC% (<80 %) of which 13 (57 %) had mild (FVC% 60–79 %), 6 (26 %) had moderate (FVC% 40–59 %), and 4 (17 %) had severe (FVC <40 %) reductions. Mean RVEF was 58.3 ± 3.7 %. Patients with abnormal FVC% were older and had lower RVEF and RVEDVI. Both RVEF and RVEDVI were significantly associated with FVC% (r = 0.31, p = 0.02 and r = 0.39, p = 0.003, respectively). In a large DMD cohort, RVEF and RVEDVI were related to FVC%. Worsening respiratory status may guide monitoring of cardiac function in these patients. 相似文献
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104.
Investigating the human immunodeficiency virus type 1-infected monocyte-derived macrophage secretome
Ciborowski P Kadiu I Rozek W Smith L Bernhardt K Fladseth M Ricardo-Dukelow M Gendelman HE 《Virology》2007,363(1):198-209
Mononuclear phagocytes (bone marrow monocyte-derived macrophages, alveolar macrophages, perivascular macrophages, and microglia) are reservoirs and vehicles of dissemination for the human immunodeficiency virus type-1 (HIV-1). How virus alters mononuclear phagocyte immunoregulatory activities to complete its life cycle and influence disease is incompletely understood. In attempts to better understanding the influence of virus on macrophage functions, we used one-dimensional electrophoresis, and liquid chromatography tandem mass spectrometry to analyze the secretome of HIV-1-infected human monocyte-derived macrophages. We identified 110 proteins in culture supernatants of control (uninfected) and virus-infected cells. Differentially expressed cytoskeletal, enzymes, redox, and immunoregulatory protein classes were discovered and validated by Western blot tests. These included, but were not limited to, cystatin C, cystatin B, chitinase 3-like 1 protein, cofilin-1, l-plastin, superoxide dismutase, leukotriene A(4) hydrolase, and alpha-enolase. This study, using a unique proteomics platform, provides novel insights into virus-host cell interactions that likely affect the functional role of macrophages in HIV disease. 相似文献
105.
We analyse the performance of statistical reconstruction (SR) methods when applied to non-continuous x-ray detectors. Robustness to projection gaps is required in x-ray CT systems with multiple detector modules or with defective detector pixels. In such situations, the advantage of statistical reconstruction is that it is able to ignore missing or faulty pixels and that it makes optimal use of the remaining line integrals. This potentially obviates the need to fill the sinogram discontinuities by interpolation or any other approximative pre-processing techniques. In this paper, we apply SR to cone beam projections of (i) a hypothetical modular detector micro-CT scanner and of (ii) a system with randomly located defective detector elements. For the modular-detector system, SR produces reconstruction volumes free of noticeable gap-induced artefacts as long as the location of detector gaps and selection of the scanning range provide complete object sampling in the central imaging plane. When applied to randomly located faulty detector elements, SR produces images free of substantial ring artefacts even for cases where defective pixels cover as much as 3% of the detector area. 相似文献
106.
Rysz J Błaszczak R Banach M Kedziora-Kornatowska K Kornatowski T Tański W Kedziora J 《Archivum immunologiae et therapiae experimentalis》2007,55(5):335-340
Introduction: The aim of the study was to evaluate some selected parameters of the antioxidative system in patients with type 2 diabetes.
Materials and Methods: Eighty-one type 2 diabetes patients took part in the study (39 patients with metabolically balanced and 42 with metabolically
unbalanced diabetes). The control group consisted of 30 healthy people. The total antioxidant capacity of plasma was measured
fluorometrically using phycoerythrin. To calculate the low-molecular-weight antioxidant concentration in the plasma samples,
the duration of Trolox activity as a function of its concentration in the sample was measured. The activity of antioxidative
enzymes in red blood cells was determined using the Misra and Fridovich method and Beers and Sizer method.
Results: The total plasma antioxidant capacity and the low-molecular-weight antioxidant concentration in the group of patients with
metabolically compensated type 2 diabetes were statistically significantly higher than in the group of patients with metabolically
uncontrolled diabetes. The activity of antioxidative enzymes was found to be higher in the group of type 2 diabetes patients
at the stage of metabolic balance.
Conclusions: The obtained results confirm the thesis of glucose toxicity and intensification of oxidative stress in patients with diabetes. 相似文献
107.
Michał Seweryn Karbownik Paweł Gunerka Paweł Turowski Maciej Wieczorek Edward Kowalczyk Wojciech Łężak Tadeusz Pietras 《Pharmacological reports : PR》2018,70(2):346-349
Background
Catalytic subunit delta of phosphoinositide 3-kinase, p110δ, encoded by the PIK3CD gene, was recently proposed as a target for pharmacological treatment of schizophrenia. Current antipsychotic drugs were found to decrease the mRNA expression of PIK3CD, but the mechanism of this process is not known. The aim of the study was to elucidate the mechanism by which antipsychotic drugs affect the mRNA expression of PIK3CD.Methods
The direct effect of haloperidol, clozapine, olanzapine, quetiapine and amisulpride on p110δ enzymatic activity was tested with a kinase assay, and the results were referenced against data on the mRNA expression of PIK3CD.Results
Haloperidol, clozapine, olanzapine and quetiapine, but not amisulpride, at the concentration of 20–80?μM, were found to significantly increase enzymatic activity of p110δ by up to two times in a dose-dependent manner. Linear regression analysis revealed that more than 40% of the variance in antipsychotic drugs-induced changes in the expression of PIK3CD mRNA was explained only by changes in antipsychotic drug-regulated p110δ enzymatic activity (p?=?0.011).Conclusions
Antipsychotic drugs differentially increase the enzymatic activity of p110δ. This effect is associated with that of mRNA expression of the PIK3CD gene. Drug-enzyme interaction may explain the effect of antipsychotic drugs on the expression of PIK3CD mRNA, however, further studies are needed to investigate this hypothesis. 相似文献108.
Gernand W Solnica B Naskalski JW 《Clinica chimica acta; international journal of clinical chemistry》2007,384(1-2):160-162
BACKGROUND: Flexible fitting of quality control procedures to method performance is an inseparable element of a cost-effective quality management strategy. However, opinions on method performance, based on a restricted number of quality control results used to calculate bias and imprecision, can vary due to the random nature of the data-gathering process. METHODS: We present an example of the bootstrap technique application in evaluating method performance estimates. RESULTS: Our analysis reveals substantial variability in method performance assessment results that should not be omitted. We suggest that the best way of using information concerning method performance is to consider the information in a probabilistic manner. Method performance is a feature presented with an element of probability. The effectiveness of a quality control procedure should be assessed with regard to this probability. CONCLUSIONS: Presented example of a bootstrap technique application increases our awareness of the uncertainty that accompanies method performance judgment and quality control planning. 相似文献
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110.