985,951 research outputs found
Expression of thyroglobulin on follicular dendritic cells of thyroid mucosa-associated lymphoid tissue (MALT) lymphoma
Reportedly, thyroid mucosa-associated lymphoid tissue (MALT) lymphoma is closely associated with Hashimoto's thyroiditis. However, it remains unknown which antigen is closely associated with thyroid MALT lymphoma. We examined whether B cell response to thyroglobulin (Tg), which is a common thyroid-specific autoantigen, is related etiologically to the pathogenesis of thyroid MALT lymphoma. Expression of human Tg antigens and Cluster of differentiation (CD) 35 was examined immunohistochemically in 15 cases of thyroid MALT lymphoma using paraffin-embedded, formalin-fixed tissue specimens. In all cases of thyroid MALT lymphoma, human Tg was detected immunohistochemically in the follicular epithelial cells and follicular dendritic cells (FDCs). These FDCs were positive by double immunostaining for anti-human Tg rabbit polyclonal antibody (Ab) and for CD35. Results showed that the Tg, a thyroid autoantigen, had immunostained the germinal center of the thyroid MALT lymphoma. The Tg was present in the FDCs, as revealed by the staining pattern of the germinal center;this fact was confirmed by double immunostaining of anti-human Tg mouse monoclonal Ab and anti-CD35 mouse monoclonal Ab. The results of our study suggest that Tg is an autoantigen that is recognized by thyroid MALT lymphoma cells.</p
Evaluation of the first automated thyroglobulin assay
The aim of this study was to investigate technical and analytical performance of the first automated thyroglobulin (Tg) assay (DPC-Immulite(R); Diagnostic Products Corporation, Los Angeles, USA). In imprecision studies using several human serum pools ranging from 21 to 58 replicates, a coefficient of variation of 9.0 % was obtained at a mean Tg concentration of 0.84 ng/ml and of 6.1 % at a Tg concentration of 62.1 ng/ml. In a method comparison with a non-automated assay (BRAHMS LUMItest Tg(R), BRAHMS, Berlin, Germany) using 383 sera of 303 patients with thyroid carcinoma, regression analysis according to Passing and Bablock yielded in the following equation: Immulite Tg=1.6 x BRAHMS Tg - 0.1 ng/ml (Pearson's r=0.979). Sera obtained from 59 patients with thyroid carcinoma enabled comparative follow-up studies; in all cases qualitative agreement was found with regard to increase or decrease of serum Tg; in eight cases, however, Tg was detected with the Immulite assay but not with the BRAHMS assay. Further follow-up proved the presence of thyroid tissue in these patients. From these and further methodological data (dilution linearity, interference studies, carry-over study, high-dose hook properties, and short report time) it is concluded that the DPC-Immulite Tg assay meets the requirements of routine diagnostic use
Observable dynamic compilation
Managed language platforms such as the Java Virtual Machine rely on a dynamic compiler to achieve high performance. Despite the benefits that dynamic compilation provides, it also introduces some challenges to program profiling. Firstly, profilers based on bytecode instrumentation may yield wrong results in the presence of an optimizing dynamic compiler, either due to not being aware of optimizations, or because the inserted instrumentation code disrupts such optimizations. To avoid such perturbations, we present a technique to make profilers based on bytecode instrumentation aware of the optimizations performed by the dynamic compiler, and make the dynamic compiler aware of the inserted code. We implement our technique for separating inserted instrumentation code from base-program code in Oracle's Graal compiler, integrating our extension into the OpenJDK Graal project. We demonstrate its significance with concrete profilers. On the one hand, we improve accuracy of existing profiling techniques, for example, to quantify the impact of escape analysis on bytecode-level allocation profiling, to analyze object life-times, and to evaluate the impact of method inlining when profiling method invocations. On the other hand, we also illustrate how our technique enables new kinds of profilers, such as a profiler for non-inlined callsites, and a testing framework for locating performance bugs in dynamic compiler implementations. Secondly, the lack of profiling support at the intermediate representation (IR) level complicates the understanding of program behavior in the compiled code. This issue cannot be addressed by bytecode instrumentation because it cannot precisely capture the occurrence of IR-level operations. Binary instrumentation is not suited either, as it lacks a mapping from the collected low-level metrics to higher-level operations of the observed program. To fill this gap, we present an easy-to-use event-based framework for profiling operations at the IR level. We integrate the IR profiling framework in the Graal compiler, together with our instrumentation-separation technique. We illustrate our approach with a profiler that tracks the execution of memory barriers within compiled code. In addition, using a deoptimization profiler based on our IR profiling framework, we conduct an empirical study on deoptimization in the Graal compiler. We focus on situations which cause program execution to switch from machine code to the interpreter, and compare application performance using three different deoptimization strategies which influence the amount of extra compilation work done by Graal. Using an adaptive deoptimization strategy, we manage to improve the average start-up performance of benchmarks from the DaCapo, ScalaBench, and Octane suites by avoiding wasted compilation work. We also find that different deoptimization strategies have little impact on steady- state performance
Moderate exercise increases affinity of large very low density lipoproteins for hydrolysis by lipoprotein lipase
Context:
Postprandial triglyceride (TG) concentration is independently associated with cardiovascular disease risk. Exercise reduces postprandial TG concentrations but the mechanisms responsible are unclear.
Objective:
To determine the effects of exercise on affinity of chylomicrons, large very low density lipoproteins (VLDL1) and smaller VLDL (VLDL2) for lipoprotein lipase (LPL) mediated TG hydrolysis.
Design:
Within-participant cross-over study.
Setting:
A University metabolic investigation unit.
Participants:
Ten overweight/obese men.
Interventions:
Participants undertook two oral fat tolerance tests, separated by 7–14 days, in which they had blood taken fasting and for 4 hours after a high-fat mixed meal. On the afternoon before one test, they performed a 90-minute treadmill walk at 50% maximal oxygen uptake (EX); no exercise was performed before the control test (CON).
Main outcome measures:
Circulating TG-rich lipoprotein concentrations; affinity of chylomicrons, VLDL1, VLDL2 for LPL-mediated TG hydrolysis.
Results:
Exercise significantly reduced fasting VLDL1-TG concentration (CON: 0.49(0.33–0.72) mmol.l−1, EX: 0.36(0.22–0.59) mmol.l−1, [geometric means (95% confidence interval)]; p=0.04). Time-averaged postprandial chylomicron-TG (CON: 0.55±0.10 mmol.l−1, EX: 0.39±0.08 mmol.l−1, [mean±SEM], p=0.03) and VLDL1-TG (CON: 0.85±0.13 mmol.l−1, EX: 0.66±0.10 mmol.l−1, p=0.01) concentrations were both lower in EX than CON. Affinity of VLDL1 for LPL-mediated TG hydrolysis increased by 2.2(1.3–3.7) fold (geometric mean (95% confidence interval)) (p=0.02) in the fasted state and 2.6(1.8–2.6) fold (p=0.001) postprandially. Affinity of chylomicrons and VLDL2 was not significantly different between trials.
Conclusions:
Exercise increases affinity of VLDL1 for LPL-mediated TG hydrolysis both fasting and postprandially. This mechanism is likely to contribute to exercise's TG-lowering effect
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