Publications by authors named "Megan R Ruth"

Obesity and its metabolic complications have emerged as the epidemic of the new millennia. The use of obese rodent models continues to be a productive component of efforts to understand the concomitant metabolic complications of this disease. In 1978, the rat model was developed with an autosomal recessive corpulent () trait resulting from a premature stop codon in the extracellular domain of the leptin receptor.

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Choline demands during lactation are high; however, detailed knowledge is lacking regarding the optimal dietary intake during this critical period. The present study was designed to determine the effects of varying intakes of choline on maternal immune function during lactation. Primiparous Sprague-Dawley rats (n 42) were randomised 24-48 h before birth and fed the following diets for 21 d: choline-devoid (0 g choline/kg diet; D, n 10); 1·0 g choline/kg diet (C1, n 11); 2·5 g choline/kg diet (C2·5, n 10); 6·2 g choline/kg diet (C6, n 11).

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Background: Although increased volume of pericardial fat has been associated with decreased cardiac function, it is unclear whether this association is mediated by systemic overall obesity or direct regional fat interactions. We hypothesized that if local effects dominate, left ventricular (LV) function would be most strongly associated with pericardial fat that surrounds the left rather than the right ventricle (RV).

Methods: Female obese subjects (n = 60) had cardiovascular magnetic resonance (CMR) scans to obtain measures of LV function and pericardial fat volumes.

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Objective: High fat, low carbohydrate (HFLC) diets have become popular tools for weight management. We sought to determine the effects of a HFLC diet compared to a low fat high carbohydrate (LFHC) diet on the change in weight loss, cardiovascular risk factors and inflammation in subjects with obesity.

Methods: Obese subjects (29.

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The intestine and the gut-associated lymphoid tissue (GALT) are essential components of whole body immune defense, protecting the body from foreign antigens and pathogens, while allowing tolerance to commensal bacteria and dietary antigens. The requirement for protein to support the immune system is well established. Less is known regarding the immune modifying properties of individual amino acids, particularly on the GALT.

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Objective: To develop an algorithm to identify and quantify BAT from PET/CT scans without radiologist interpretation.

Design And Methods: Cases (n = 17) were randomly selected from PET/CT scans with documented "brown fat" by the reviewing radiologist. Controls (n = 18) had no documented "brown fat" and were matched with cases for age (49.

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Purpose Of Review: Cancer cell metabolism is characterized by high rates of glucose uptake and anaerobic glycolysis. Sugar consumption has increased dramatically in the industrialized world, with refined fructose intake skyrocketing upwards in the USA over the past 30 years. Fructose provides an alternative carbon source for glycolysis, entering downstream of glucose and bypassing two key rate-limiting steps.

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Scope: Evidence suggests a neutral to beneficial role of certain trans fatty acids (TFA) from natural ruminant sources. Trans11-18:1 (vaccenic acid, VA), the most predominant ruminant TFA and a precursor to conjugated linoleic acid, has been shown to improve atherogenic dyslipidemia and symptoms of hepatic steatosis in animal models. The objective of this study was to assess the intestinal bioavailability of various VA sources including synthetic free fatty acid (FFA) and natural ruminant triglyceride forms, as well as the mechanistic pathways that mediate VA's bioactivity.

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Board certification and credentialing in nutrition for physicians are problematic issues. Many board examinations are offered, but have few candidates and poor recognition. This discussion focuses on the feasibility of establishing a single board examination body.

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Background: Conjugated linoleic acid (cis-9, trans-11 CLA) and trans-11 vaccenic acid (VA) are found naturally in ruminant-derived foods. CLA has been shown to have numerous potential health related effects and has been extensively investigated. More recently, we have shown that VA has lipid-lowering properties associated with reduced hepatic lipidogenesis and chylomicron secretion in the JCR:LA-cp rat.

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This study assessed the long-term effects of dietary vaccenic acid (VA) and elaidic acid (EA) on plasma and splenocyte phospholipid (PL) composition and related changes in inflammation and splenocyte phenotypes and cytokine responses in obese/insulin resistant JCR:LA-cp rats. Relative to lean control (Ctl), obese Ctl rats had higher serum haptoglobin and impaired T-cell-stimulated cytokine responses. VA and EA diets improved T-cell-stimulated cytokine production; but, only VA normalized serum haptoglobin.

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Trans-11 vaccenic acid (VA) is the predominant trans isomer in ruminant fat and a major precursor to the endogenous synthesis of cis9,trans11-conjugated linoleic acid in humans and animals. We have previously shown that 3-wk VA supplementation has a triglyceride (TG)-lowering effect in a rat model of dyslipidemia, obesity, and metabolic syndrome (JCR:LA-cp rats). The objective of this study was to assess the chronic effect (16 wk) of VA on lipid homeostasis in both the liver and intestine in obese JCR:LA-cp rats.

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Vaccenic acid (VA) is a ruminant-derived trans-fat and precursor of conjugated linoleic acid (CLA). The objective of the present study was to explore the effects of VA on immune function in a model of the metabolic syndrome, JCR:LA-cp rats. Lean (2:1 mix of +/cp and +/+) and obese (cp/cp) rats, aged 8 weeks, were fed a control (0% VA) or a VA diet (1.

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Dietary EPA and DHA modulate immunity and thereby may improve the aberrant immune function in obese states. To determine the effects of feeding fish oil (FO) containing EPA and DHA on splenocyte phospholipid (PL) and lipid-raft fatty acid composition, phenotypes and cytokine production, 14-week-old obese, leptin receptor-deficient JCR:LA-cp rats (cp/cp; n 10) were randomised to one of three nutritionally adequate diets for 3 weeks: control (Ctl, 0 % EPA+DHA); low FO (LFO, 0.8 % (w/w) EPA+DHA); high FO (HFO, 1.

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Trans-11 vaccenic acid [VA; 18:1(n-9)] is a positional and geometric isomer of oleic acid and is the precursor to conjugated linoleic acid (CLA) in humans. Despite VA being the predominant trans monoene in ruminant-derived lipids, very little is known about its nutritional bioactivity, particularly in conditions of chronic metabolic disorders, including obesity, insulin resistance, and/or dyslipidemia. The aim of this study was to assess the potential of VA to improve dyslipidemia, insulin sensitivity, or inflammatory status in obese and insulin-resistant JCR:LA-cp rats.

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CVT-E002 (sold commercially as COLD-fX) is a patented, polysaccharide-rich extract of North American ginseng (Panax quinquefolium) with purported beneficial effects on influenza and the common cold, although its mechanism of action is largely unknown. This study was conducted to determine the effects of feeding CVT-E002 versus a ginsenoside-containing extract on systemic and gut-associated immune function. For 7 days, male weanling Sprague-Dawley rats (n=10/group) were fed one of four diets: control, low CVT-E002 (450 mg/kg), high CVT-E002 (900 mg/kg), or ginsenoside (450 mg/kg).

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Objective: The objective of this study was to characterize immune function in the fa/fa Zucker rat, and to determine the effects of feeding conjugated linoleic acid (CLA) isomers on immune function.

Methods And Procedures: Lean and fa/fa Zucker rats were fed for 8 weeks nutritionally complete diets with different CLA isomers (%wt/wt): control (0%), c9t11 (0.4%), t10c12 (0.

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