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61.
Rosuvastatin Enhances the Catabolism of LDL apoB‐100 in Subjects with Combined Hyperlipidemia in a Dose Dependent Manner
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Ngoc‐Anh Le Margaret R. Diffenderfer Nuntakorn Thongtang Esther M. M. Ooi P. Hugh R. Barrett Katalin V. Horvath Gregory G. Dolnikowski Bela F. Asztalos Ernst J. Schaefer W. Virgil Brown 《Lipids》2015,50(5):447-458
Dose‐associated effects of rosuvastatin on the metabolism of apolipoprotein (apo) B‐100 in triacylglycerol rich lipoprotein (TRL, d < 1.019 g/ml) and low density lipoprotein (LDL) and of apoA‐I in high density lipoprotein (HDL) were assessed in subjects with combined hyperlipidemia. Our primary hypothesis was that maximal dose rosuvastatin would decrease the apoB‐100 production rate (PR), as well as increase apoB‐100 fractional catabolic rate (FCR). Eight subjects received placebo, rosuvastatin 5 mg/day, and rosuvastatin 40 mg/day for 8 weeks each in sequential order. The kinetics of apoB‐100 in TRL and LDL and apoA‐I in HDL were determined at the end of each phase using stable isotope methodology, gas chromatography‐mass spectrometry, and multicompartmental modeling. Rosuvastatin at 5 and 40 mg/day decreased LDL cholesterol by 44 and 54 % (both P < 0.0001), triacylglycerol by 14 % (ns) and 35 % (P < 0.01), apoB by 30 and 36 % (both P < 0.0001), respectively, and had no significant effects on HDL cholesterol or apoA‐I levels. Significant decreases in plasma markers of cholesterol synthesis and increases in cholesterol absorption markers were observed. Rosuvastatin 5 and 40 mg/day increased TRL apoB‐100 FCR by 36 and 46 % (both ns) and LDL apoB‐100 by 63 and 102 % (both P < 0.05), respectively. HDL apoA‐I PR increased with low dose rosuvastatin (12 %, P < 0.05) but not with maximal dose rosuvastatin. Neither rosuvastatin dose altered apoB‐100 PR or HDL apoA‐I FCR. Our data indicate that maximal dose rosuvastatin treatment in subjects with combined hyperlipidemia resulted in significant increases in the catabolism of LDL apoB‐100, with no significant effects on apoB‐100 production or HDL apoA‐I kinetics. 相似文献
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Brady Sonya S.; Dolcini M. Margaret; Harper Gary W.; Pollack Lance M. 《Canadian Metallurgical Quarterly》2009,28(2):238
Objective: This study examined whether uncontrollable stressful life events were associated with sexual risk taking among adolescents across a 1-year period, and whether supportive friendships modified associations. Design: Participants were 159 sexually active African American adolescents (57% male; mean age [SD] = 17.0 [1.5] years at baseline). Participants were recruited for in-person interviews through random digit dialing in one inner-city neighborhood characterized by high rates of poverty and crime relative to the surrounding city. Main Outcome Measures: Dependent variables included substance use before sexual activity and inconsistent condom use. Results: Among adolescents who reported low levels of supportive friendships, uncontrollable stressors were associated with greater levels of sexual risk taking over time. In contrast, uncontrollable stressors were not associated with sexual risk taking among adolescents who reported high social support from friends; risk taking was typically moderate to high among these adolescents. Conclusion: Different processes may explain sexual risk taking among adolescents with varying levels of social support from friends. Adolescents with low support may be prone to engagement in health risk behavior as a stress response, while adolescents with high support may engage in risk behavior primarily due to peer socialization of risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Black soybean is a potential functional food ingredient with high anthocyanin content, but the ability to maintain anthocyanin content under dry heat processing has not been reported. This study investigated the effects of soybean seed coat colour and baking time–temperature combinations on the extractable antioxidant properties of a soy cracker food model. Crackers prepared with black soybeans had significantly higher TPC, total isoflavones, and peroxyl, hydroxyl, and ABTS+ radical scavenging abilities than their yellow counterparts, at all time–temperature combinations. Cyanidin-3-glucoside (C3G) was detected only in black soybean crackers, and all baking treatments significantly decreased C3G. The greatest losses occurred at the low temperature × long time and high temperature × short time, the smallest loss with moderate temperature × short/medium time. The high temperature treatment altered phenolic acid and isoflavone profiles; however, total isoflavones were unaffected. Overall results suggest that moderate baking temperature at minimal time may best preserve anthocyanin and other phenolics in baked black soybean crackers. 相似文献
66.
Staub Adrian; Grant Margaret; Clifton Charles Jr.; Rayner Keith 《Canadian Metallurgical Quarterly》2011,37(5):1326
In this brief rejoinder, we respond to Farmer, Monaghan, Misyak, and Christiansen (2011). We argue that the data still do not support the claim that reading time is affected by the phonological typicality of a word for its part of speech. We also question Farmer et al.'s claim that interleaving syntactic structures in an experiment modifies grammatically based syntactic expectations. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
67.
This study examined the effectiveness of the opposing expert safeguard against unreliable expert testimony and whether beliefs about experts as hired guns and general acceptance mediate the effect of opposing expert testimony on juror decisions. We found strong evidence that the presence, but not the content, of opposing expert testimony affected jurors’ trial judgments and that these effects were mediated by mock jurors’ beliefs about general acceptance. The presence of an opposing expert affected jurors’ ratings of the general acceptance of research investigating sexual harassment in the workplace. Jurors’ beliefs about general acceptance then affected jurors’ ratings of plaintiff expert competence and research, which affected juror ratings of the probability that the plaintiff experienced a hostile work environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Nathan A. Tregger Margaret E. Pakula Surendra P. Shah 《Cement and Concrete Research》2010,40(3):384-391
The fresh state of concrete is becoming increasingly important in furthering the types of applications of today's construction world. Processing techniques have resulted in technologies such as self-consolidating concrete and depend on the microstructural changes that take place during and immediately after mixing and placing. These changes to the microstructure reflect the flocculation behavior between the particles in suspension. The ability to modify this behavior allows control over the balance among flowability and shape-stability of concrete. This study investigates how clay admixtures affect the microstructure of cement pastes from a rheological stand point. Shear and compressive rheology techniques are used to measure how the solids volume fraction of suspensions with different admixtures evolves with stress. Based on these relationships, the effectiveness of clays on the balance between flowability and shape-stability is measured. Results are consistent with green strength tests performed on concrete mixes derived from the cement paste mixes. 相似文献
69.
The objective of this study was to compare objective and subjective methods of collecting exposure time data for hand arm vibration (HAV) and whole-body vibration (WBV), and to evaluate the impact of inaccurate exposure times’ on the calculation of the average vibration exposure over an 8 h working day A(8).The study was carried out in the engineering services and maintenance departments of a construction and property management company. Worker exposure time data was collected using three methods, questionnaire surveys, daily worker interviews and 8 h direct workplace observations. Vibration magnitudes (m/s2) were measured for a range of hand tools and vehicles, and daily vibration exposure estimates A(8) were calculated using exposure times observed, reported in interview and self reported in the questionnaire.Results from the study showed that self-reported exposure time estimates from the questionnaire survey were a factor of 9.0 (median value) times greater for HAV and a factor of 6.0 (median value) times greater for WBV when compared with direct observation estimates. Exposure times reported in interview were higher, than those observed, but more reliable than those self reported in the questionnaire; a factor of 2.1 (median value) times greater for HAV and a factor of 1.4 (median value) times greater for WBV. A(8) values calculated using questionnaire exposure times were up to 66% and 75% greater for sources of HAV and WBV respectively when compared to A(8) values calculated using observed exposure times.For the purposes of carrying out a reliable risk assessment, results from this study indicate that direct measurements of worker exposure time are not recommended over questionnaires especially where work is highly variable for example in construction and property management. Worker interviews or direct workplace observation methods were found to be reliable alternative methods for collecting exposure time. 相似文献
70.
Anthony J. Prenni Ronald L. Siefert Timothy B. Onasch Margaret A. Tolbert Paul J. Demott 《Aerosol science and technology》2013,47(5):465-481
A fluidized bed aerosol generator has been designed and built for the purpose of generating a constant output of dry, submicrometer particles with a large number density. The output of the fluidized bed for generating aerosol particles from dry soot powder has been characterized using a differential mobility analyzer and a condensation particle counter. The particle size distribution is bimodal, with a mode in the submicrometer diameter size range and a mode in the supermicrometer diameter size range. The larger diameter mode is fully separated from the smaller mode and can thus be easily removed from the aerosol flow using impaction techniques. The distribution in the submicrometer size range is nearly log-normal, with a count median diameter falling between 0.1 and 0.3 micrometers. A number density of greater than 105 particles cm-3 of soot particles in the submicrometer range can be produced, constant to within 25% (1 standard deviation) over a 4 h time period. The number density of particles produced in the submicrometer range was found to vary with the ratio of soot to bronze beads in the bed mixture, whether or not a feed system was used, and nitrogen flow rate through the fluidized bed and feed system. 相似文献