Adding MUFA to a dietary portfolio of cholesterol-lowering foods reduces apoAI fractional catabolic rate in subjects with dyslipidaemia

The present randomised parallel study assessed the impact of adding MUFA to a dietary portfolio of cholesterol-lowering foods on the intravascular kinetics of apoAI- and apoB-containing lipoproteins in subjects with dyslipidaemia. A sample of sixteen men and postmenopausal women consumed a run-in stabilisation diet for 4 weeks. Subjects were then randomly assigned to an experimental dietary portfolio either high or low in MUFA for another 4 weeks. MUFA substituted 13·0 % of total energy from carbohydrate (CHO) in the high-MUFA dietary portfolio. Lipoprotein kinetics were assessed after the run-in and portfolio diets using a primed, constant infusion of [2H3]leucine and multicompartmental modelling. The high-MUFA dietary portfolio resulted in higher apoAI pool size (PS) compared with the low-MUFA dietary portfolio (15·9 % between-diet difference, P= 0·03). This difference appeared to be mainly attributable to a reduction in apoAI fractional catabolic rate (FCR) after the high-MUFA diet ( − 5·6 %, P= 0·02 v. pre-diet values), with no significant change in production rate. The high-MUFA dietary portfolio tended to reduce LDL apoB100 PS compared with the low-MUFA dietary portfolio ( − 28·5 % between-diet difference, P= 0·09), predominantly through an increase in LDL apoB100 FCR (23·2 % between-diet difference, P= 0·04). These data suggest that adding MUFA to a dietary portfolio of cholesterol-lowering foods provides the added advantage of raising HDL primarily through a reduction in HDL clearance rate. Replacing CHO with MUFA in a dietary portfolio may also lead to reductions in LDL apoB100 concentrations primarily by increasing LDL clearance rate, thus potentiating further the well-known cholesterol-lowering effect of this diet.

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Catabolism of Human Fibrinogen Fragment D in Normal Subjects and Patients with Liver Cirrhosis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650106 ◽

1980 ◽

Vol 44 (03) ◽

pp. 146-149 ◽

Cited By ~ 3

Author(s):

Nicole Ardaillou ◽

Jeannine Yvart ◽

Philippe Le Bras ◽

Marie-José Larrieu

Keyword(s):

Liver Cirrhosis ◽

Clearance Rate ◽

Plasma Clearance ◽

Normal Subjects ◽

Fractional Catabolic Rate ◽

Human Fibrinogen ◽

Plasma Pool ◽

Catabolic Rate ◽

Chloramine T

SummaryThe catabolism of human fragment D, (FgD), obtained by plasmin digestion of fibrinogen has been investigated in normal subjects and patients with liver cirrhosis and the results compared with those obtained for fibrinogen (Fg). Fg was labelled with I-125 and Fg D with I-131 using the chloramine T method. The plasma disappearance curves of both labelled proteins fitted a two exponential curve. In controls the plasma clearance rate of Fg D was greater than that of Fg as shown by the marked difference between the half-lives of these two tracers: 8,9 and 83,5 hours for Fg D and Fg respectively. The fractional catabolic rate of Fg D was 3.38 times the plasma pool per day. In nine patients with liver cirrhosis, catabolism of Fg was not modified. In contrast, catabolism of Fg D was significantly reduced with a half life of 13.0 hours and a low fractional catabolic rate. These results suggest the role of the liver in the catabolism of Fg D in man.

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Kinetic Studies of Fibrinogen in Pregnant Rabbits

10.1055/s-0039-1682442 ◽

1977 ◽

Author(s):

R.-M. Moeller ◽

I. Mahn ◽

G. Müller-Berqhaus

Keyword(s):

Kinetic Studies ◽

Distribution Volume ◽

Fractional Catabolic Rate ◽

Third Trimester ◽

The Third ◽

Quantitative Measurements ◽

Catabolic Rate ◽

Average Acceleration ◽

The Mean ◽

Kinetics Of

During gestation increased concentrations of fibrin (ogen)derivatives are observed indicative of intravascular action of thrombin. The aim of this study was to elucidate the kinetics of fibrinogen during gestation. The elimination of homologous 1-125-fibrinogen was studied in 14 pregnant rabbits during the first as well as during the third trimesters of gestation. Control studies were performed with 10 non-pregnant rabbits.The mean distribution volume of labeled fibrinogen did not significantly differ between pregnant and non-pregnant rabbits. During the third trimester pregnant rabbits demonstrated a pronounced shortening of T 1/2 of labeled fibrinogen from a mean of 55.3 hr during the first to a mean of 29.7 hr during the third trimester. The experiments showed a significant increase in the fractional catabolic rate from 45.0 to 69.9% per day in the course of gestation. The shortening of T 1/2 of labeled fibrinogen correlated to the number of fetusses per litter.This study indicates an average acceleration of the fibrinogen turnover during gestation of about 50%. These direct quantitative measurements demonstrate that fibrinogen catabolism is pronouncedly accelerated during pregnancy.

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Comparison of a dietary portfolio diet of cholesterol-lowering foods and a statin on LDL particle size phenotype in hypercholesterolaemic participants

British Journal Of Nutrition ◽

10.1017/s0007114507781461 ◽

2007 ◽

Vol 98 (6) ◽

pp. 1229-1236 ◽

Cited By ~ 21

Author(s):

Iris Gigleux ◽

David J. A. Jenkins ◽

Cyril W. C. Kendall ◽

Augustine Marchie ◽

Dorothea A. Faulkner ◽

...

Keyword(s):

Particle Size ◽

Control Diet ◽

Random Order ◽

Statin Treatment ◽

Cholesterol Lowering ◽

Ldl Particle Size ◽

Cholesterol Levels ◽

Ldl Size ◽

Dietary Portfolio ◽

The Impact

The effect of diet v. statins on LDL particle size as a risk factor for CVD has not been examined. We compared, in the same subjects, the impact of a dietary portfolio of cholesterol-lowering foods and a statin on LDL size electrophoretic characteristics. Thirty-four hyperlipidaemic subjects completed three 1-month treatments as outpatients in random order: a very-low saturated fat diet (control); the same diet with 20 mg lovastatin; a dietary portfolio high in plant sterols (1 g/4200 kJ), soya proteins (21·4 g/4200 kJ), soluble fibres (9·8 g/4200 kJ) and almonds (14 g/4200 kJ). LDL electrophoretic characteristics were measured by non-denaturing polyacrylamide gradient gel electrophoresis of fasting plasma at 0, 2 and 4 weeks of each treatment. The reductions in plasma LDL-cholesterol levels with the dietary portfolio and with statins were comparable and were largely attributable to reductions in the estimated concentration of cholesterol within the smallest subclass of LDL (portfolio − 0·69 (se 0·10) mmol/l, statin − 0·99 (se 0·10) mmol/l). These were significantly greater (P < 0·01) than changes observed after the control diet ( − 0·17 (se 0·08) mmol/l). Finally, baseline C-reactive protein levels were a significant predictor of the LDL size responsiveness to the dietary portfolio but not to the other treatments. The dietary portfolio, like the statin treatment, had only minor effects on several features of the LDL size phenotype, but the pronounced reduction in cholesterol levels within the small LDL fraction may provide additional cardiovascular benefit over the traditional low-fat diet of National Cholesterol Education Program Step II.

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Measuring VLDL1-Triglyceride and VLDL2-Triglyceride Kinetics in Men: Effects of Dietary Control on Day-to-Day Variability

Hormone and Metabolic Research ◽

10.1055/s-0043-109561 ◽

2017 ◽

Vol 49 (08) ◽

pp. 604-611

Author(s):

Rakel Johansen ◽

Esben Søndergaard ◽

Lars Sørensen ◽

Anne Jurik ◽

Søren Nielsen

Keyword(s):

Clearance Rate ◽

Ex Vivo ◽

Diet Group ◽

Constant Infusion ◽

Dietary Control ◽

Isocaloric Diet ◽

Diet Intervention ◽

The Difference ◽

The Impact ◽

Total Triglyceride

AbstractThe aim of this study was to assess the impact of dietary control on VLDL1- and VLDL2-TG kinetics and associated metabolic parameters. Twelve overweight/obese men were randomized to a provided 3 day isocaloric diet with fixed macronutrient composition (diet group, n=6) or to their regular unrestricted diet (non-diet group, n=6). VLDL1- and VLDL2-TG turnovers were measured twice 2–4 weeks apart, using primed-constant infusion of ex vivo labeled [1-14C]VLDL1-TG and [9,10-3H]VLDL2-TG. Isocaloric diet intervention lowered the difference in the mean of both VLDL2-TG secretion and clearance rate (p<0.01), and the coefficient of variation (CV) of VLDL2-TG clearance rate (p<0.05). The difference in mean and CV of the other kinetic estimates (VLDL1-TG secretion, clearance and oxidation rate) were lowered, but not significantly. The CV’s of total triglyceride, VLDL1-TG, and VLDL2-TG concentrations were significantly lowered by diet intervention compared to regular diet; total triglyceride (31%–5%, p<0.01), VLDL1-TG (42%–9%, p<0.01), and VLDL2-TG (36%–10%, p<0.01). In conclusion, VLDL1- and VLDL2-TG kinetics show great day-to-day variability, which may be diminished by diet intervention. Therefore, standardized macronutrient intake prior to study days improves the probability of demonstrating significant outcomes of cross-sectional and intervention studies of VLDL1-TG and VLDL2-TG kinetics and metabolism.

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Fibrinogen Catabolism: Kinetics of Catabolism following Sudden Elevation of the Pool with Exogenous Fibrinogen

Clinical Science ◽

10.1042/cs0380111 ◽

1970 ◽

Vol 38 (1) ◽

pp. 111-121 ◽

Cited By ~ 34

Author(s):

E. Regoeczi

Keyword(s):

Synthesis Rate ◽

Order Kinetic ◽

Fractional Catabolic Rate ◽

Kinetic Reaction ◽

First Order ◽

Catabolic Rate ◽

Before And After ◽

Total Body ◽

Kinetics Of ◽

Metabolic Tracers

1. Fibrinogen catabolism was studied in ten rabbits before and after suddenly elevating the intravascular pool by injecting a single dose of homologous fibrinogen equivalent to 18–83% of the corresponding protein already present in this pool. Of the two metabolic tracers used, [131I]fibrinogen was injected 3–4 days before and [125I]fibrinogen at the time of introducing the change. 2. Analysis of total body as well as of the circulating radioactivities indicated that the excess protein did not affect the fractional catabolic rate constant, thus permitting the conclusion that fibrinogen catabolism closely follows a first order kinetic reaction. In some animals a fraction of the injected fibrinogen shifted to extravascular sites and altered the pool ratio. Elimination of the excess protein took about 5 days and was accompanied by changes in the synthesis rate of fibrinogen.

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Some Factors Influencing Metabolism and Distribution of Fibrinogen in Man and Rabbits

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649225 ◽

1977 ◽

Vol 37 (02) ◽

pp. 243-252

Author(s):

Yi-Hsiang Chen ◽

E. B Reeve

Keyword(s):

Plasma Fibrinogen ◽

Synthesis Rate ◽

Fibrinogen Concentration ◽

Fractional Catabolic Rate ◽

System Parameters ◽

Catabolic Rate ◽

Simultaneous Decrease ◽

Normal Males ◽

Healthy Females ◽

Made In

SummaryTo shed some light on the homeostatic regulation of plasma fibrinogen, metabolic studies were made in healthy females, and in normal, thyroidectomized, and thyroxine-treated rabbits. In females, compared with normal males, plasma fibrinogen concentration, plasma and interstitial fibrinogen decreased consequent to an increased fractional catabolic rate and a normal fibrinogen synthesis rate. The interstitial/plasma fibrinogen ratio remained unchanged. In normal rabbits, with increasing body weight fractional catabolic rate and catabolic rate decreased, while fibrinogen concentration and plasma fibrinogen remained constant owing to a simultaneous decrease in fibrinogen synthesis. In addition, fractional transcapillary transfer rate and transcapillary flux also decreased resulting in a shrinkage of interstitial fibrinogen. Thyroidectomy and thyroxine-injection markedly altered fibrinogen metabolism: thyroid hormone accelerated fibrinogen catabolism but also stimulated synthesis. The net result was an increase in plasma fibrinogen and fibrinogen concentration. The interstitial/plasma fibrinogen ratio decreased in thyroxine-treated, and increased in thyroidectomized animals. This study defines the variations of the fibrinogen system parameters in these physiologic and pathologic conditions, and illustrates some patterns of alterations in fibrinogen metabolism.

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Ice Coverage Induced by Depositing a Water Drop onto the Supercooled Substrate at Extreme Low Vapor Pressure

Crystals ◽

10.3390/cryst11060691 ◽

2021 ◽

Vol 11 (6) ◽

pp. 691

Author(s):

Yugang Zhao ◽

Zichao Zuo ◽

Haibo Tang ◽

Xin Zhang

Keyword(s):

Vapor Pressure ◽

Substrate Temperature ◽

Water Drop ◽

Industrial Processes ◽

Aircraft Icing ◽

Ice Coverage ◽

Fundamental Understanding ◽

Order Of Magnitude ◽

The Impact ◽

Kinetics Of

Icing/snowing/frosting is ubiquitous in nature and industrial processes, and the accretion of ice mostly leads to catastrophic consequences. The existing understanding of icing is still limited, particularly for aircraft icing, where direct observation of the freezing dynamics is inaccessible. In this work, we investigate experimentally the impact and freezing of a water drop onto the supercooled substrate at extremely low vapor pressure, to mimic an aircraft passing through clouds at a relatively high altitude, engendering icing upon collisions with pendant drops. Special attention is focused on the ice coverage induced by an impinging drop, from the perimeter pointing outward along the radial direction. We observed two freezing regimes: (I) spread-recoil-freeze at the substrate temperature of Ts = −15.4 ± 0.2 °C and (II) spread (incomplete)-freeze at the substrate temperature of Ts = −22.1 ± 0.2 °C. The ice coverage is approximately one order of magnitude larger than the frozen drop itself, and counterintuitively, larger supercooling yields smaller ice coverage in the range of interest. We attribute the variation of ice coverage to the kinetics of vapor diffusion in the two regimes. This fundamental understanding benefits the design of new anti-icing technologies for aircraft.

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Morphology and crystallization kinetics of Rubber-modified Nylon 6 Prepared by Anionic In-situ Polymerization

Science and Engineering of Composite Materials ◽

10.1515/secm-2020-0020 ◽

2020 ◽

Vol 27 (1) ◽

pp. 204-215

Author(s):

Hongkai Zhao ◽

Dengchao Zhang ◽

Yingshuang Li

Keyword(s):

Crystallization Kinetics ◽

In Situ Polymerization ◽

Good Description ◽

Nylon 6 ◽

Avrami Equation ◽

Infrared Analysis ◽

Chain Segment ◽

The Impact ◽

Kinetics Of

AbstractIn this work, we modified nylon 6 with liquid rubber by in-situ polymerization. The infrared analysis suggested that HDI urea diketone is successfully blocked by caprolactam after grafting on hydroxyl of HTPB, and the rubber-modified nylon copolymer is generated by the anionic polymerization. The impact section analysis indicated the rubber-modified nylon 6 resin exhibited an alpha crystal form.With an increase in the rubber content, nylon 6 was more likely to generate stable α crystal. Avrami equation was a good description of the non-isothermal crystallization kinetics of nylon-6 and rubber-modified nylon-6 resin. Moreover, it is found that the initial crystallization temperature of nylon-6 chain segment decreased due to the flexible rubber chain segment. n value of rubber-modified nylon-6 indicated that its growth was the coexistence of two-dimensional discoid and three-dimensional spherulite growth. Finally, the addition of the rubber accelerated the crystallization rate of nylon 6.

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Statin use is associated with reduced motor recovery after spinal cord injury

Spinal Cord Series and Cases ◽

10.1038/s41394-020-00378-y ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Erin M. Triplet ◽

Isobel A. Scarisbrick

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Motor Recovery ◽

Motor Deficit ◽

Historical Cohort ◽

Cholesterol Lowering ◽

Severity Of Injury ◽

Cord Injury ◽

The Impact ◽

Statin Use

Abstract Study design We completed retrospective analysis of statin use in individuals with neurologically significant spinal cord injury in a historical cohort study. Objective Our objective was to establish the prevalence of cholesterol-lowering agent use following spinal cord injury (SCI) and to determine the impact on recovery of motor function. Setting Patients enrolled in the Rochester Epidemiology Project in Olmsted County, Minnesota, USA from 2005 to 2018 were included in analysis. Methods Exclusion criteria: age <18, comorbid neurological disease, prior neurological deficit, nontraumatic injury, survival <1 year, or lack of motor deficit. Demographics and cholesterol-lowering agent use in 83 individuals meeting all criteria were recorded. A total of 68/83 individuals were then assessed for change in function over the first 2 months after injury using the ISNCSCI motor subscore. Statistical comparison between control and statin groups was done by two-sided Chi-squared test or two-tailed Student’s t test. Generalized regression was performed to assess associations between independent variables and functional outcome. Results 30% of individuals with SCI had a prescription for a cholesterol-lowering agent. No significant differences were observed in severity of injury or demographic composition between groups. The change in motor subscore was reduced in the statin group compared to controls (p = 0.03, Mann–Whitney). Both severity of injury and statin were significant predictors of reduced motor recovery (p = 0.001, and p = 0.04, respectively). Conclusions Both severity of SCI and statins were significant predictors of reduced motor recovery. Additional investigation is needed to address potential impact of statin-therapy in the context of CNS injury and repair.

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Single entity electrochemistry and the electron transfer kinetics of hydrazine oxidation

Nano Research ◽

10.1007/s12274-021-3353-8 ◽

2021 ◽

Cited By ~ 1

Author(s):

Ruiyang Miao ◽

Lidong Shao ◽

Richard G. Compton

Keyword(s):

Electron Transfer ◽

Bulk Solution ◽

Relative Contribution ◽

Rate Determining Step ◽

Multistep Process ◽

Ph Range ◽

Electro Catalytic Oxidation ◽

Single Particle Impact ◽

The Impact ◽

Kinetics Of

AbstractThe mechanism and kinetics of the electro-catalytic oxidation of hydrazine by graphene oxide platelets randomly decorated with palladium nanoparticles are deduced using single particle impact electrochemical measurements in buffered aqueous solutions across the pH range 2–11. Both hydrazine, N2H4, and protonated hydrazine N2H5+ are shown to be electroactive following Butler-Volmer kinetics, of which the relative contribution is strongly pH-dependent. The negligible interconversion between N2H4 and N2H5+ due to the sufficiently short timescale of the impact voltammetry, allows the analysis of the two electron transfer rates from impact signals thus reflecting the composition of the bulk solution at the pH in question. In this way the rate determining step in the oxidation of each specie is deduced to be a one electron step in which no protons are released and so likely corresponds to the initial formation of a very short-lived radical cation either in solution or adsorbed on the platelet. Overall the work establishes a generic method for the elucidation of the rate determining electron transfer in a multistep process free from any complexity imposed by preceding or following chemical reactions which occur on the timescale of conventional voltammetry.

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