Publications by authors named "Malloy C"

Background: Metabolic substrate utilization in HFpEF (heart failure with preserved ejection fraction), the leading cause of heart failure worldwide, is pivotal to syndrome pathogenesis and yet remains ill defined. Under resting conditions, oxidation of free fatty acids (FFA) is the predominant energy source of the heart, supporting its unremitting contractile activity. In the context of disease-related stress, however, a shift toward greater reliance on glucose occurs.

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Most kidney cancers are metabolically dysfunctional, but how this dysfunction affects cancer progression in humans is unknown. We infused C-labelled nutrients in over 80 patients with kidney cancer during surgical tumour resection. Labelling from [U-C]glucose varies across subtypes, indicating that the kidney environment alone cannot account for all tumour metabolic reprogramming.

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Highly bioavailable inorganic phosphate (Pi) is present in large quantities in the typical Western diet and represents a large fraction of total phosphate intake. Dietary Pi excess induces exercise intolerance and skeletal muscle mitochondrial dysfunction in normal mice. However, the relevance of this to humans remains unknown.

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Background: Up to 50% of people scheduled for screening colonoscopy do not complete this test and no studies have focused on minority and low-income populations. Interventions are needed to improve colorectal cancer (CRC) screening knowledge, reduce barriers, and provide alternative screening options. Patient navigation (PN) and tailored interventions increase CRC screening uptake, however there is limited information comparing their effectiveness or the effect of combining them.

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Objective: Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, insulin resistance, and hepatic steatosis (HS). Because dietary essential amino acid (EAA) supplementation has been shown to decrease HS in various populations, this study's objective was to determine whether supplementation would decrease HS in PCOS.

Methods: A randomized, double-blind, crossover, placebo-controlled trial was conducted in 21 adolescents with PCOS (BMI 37.

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Purpose: Pyruvate, produced from either glucose, glycogen, or lactate, is the dominant precursor of cerebral oxidative metabolism. Pyruvate dehydrogenase (PDH) flux is a direct measure of cerebral mitochondrial function and metabolism. Detection of [ C]bicarbonate in the brain from hyperpolarized [1- C]pyruvate using carbon-13 ( C) MRI provides a unique opportunity for assessing PDH flux in vivo.

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Improving understanding of behaviors that increase or reduce cancer risk for different Hispanic groups is a public health priority; such knowledge is sparse in new gateway immigration locations such as Indiana. The aims of this study were to: 1) describe cancer beliefs and cancer preventive/risk reduction behaviors (physical activity, tobacco, and alcohol use) among Hispanic adults; 2) examine differences in cancer beliefs and preventive behaviors by country/territory of birth, socioeconomic status, and area of residence (urban vs. rural); and 3) determine predictors of engagement in cancer prevention and risk reduction behaviors in this population.

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Article Synopsis
  • Stable isotopes help assess metabolism, and the new MS method can identify all isotopomers of aspartate and glutamate using less than 1% of the sample required for NMR.
  • This method improves the specificity in distinguishing between metabolic pathways that yield the same count of carbon labels in these amino acids.
  • The approach reveals metabolic differences in human tumors and the role of fumarate hydratase deficiency in renal cancers, enhancing in vivo isotope-labeling studies.
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Renal metabolism is essential for kidney functions and energy homeostasis in the body. The TCA cycle is the hub of metabolism, but the metabolic activities of the cycle in the kidney have rarely been investigated. This study is to assess metabolic processes at the level of the TCA cycle in the kidney based on isotopomer distributions in multiple metabolites.

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Background: Glycerol is a substrate for gluconeogenesis and fatty acid esterification in the liver, processes which are upregulated in obesity and may contribute to excess fat accumulation. Glycine and glutamate, in addition to cysteine, are components of glutathione, the major antioxidant in the liver. In principle, glycerol could be incorporated into glutathione via the TCA cycle or 3-phosphoglycerate, but it is unknown whether glycerol contributes to hepatic de novo glutathione biosynthesis.

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The affective polarization characteristic of the United States' political climate contributes to pervasive intergroup tension. This tension polarizes basic aspects of person perception, such as face impressions. For instance, face impressions are polarized by partisanship disclosure such that people form positive and negative impressions of, respectively, shared and opposing partisan faces.

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Currently, many prostate cancer patients, detected through the prostate specific antigen test, harbor organ-confined indolent disease that cannot be differentiated from aggressive cancer according to clinically and pathologically known measures. Spermine has been considered as an endogenous inhibitor for prostate-confined cancer growth and its expression has shown correlation with prostate cancer growth rates. If established clinically, measurements of spermine bio-synthesis rates in prostates may predict prostate cancer growth and patient outcomes.

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Anaerobic microbial metabolism drives critical functions within global ecosystems, host-microbiota interactions, and industrial applications, yet remains ill-defined. Here we advance a versatile approach to elaborate cellular metabolism in obligate anaerobes using the pathogen Clostridioides difficile, an amino acid and carbohydrate-fermenting Clostridia. High-resolution magic angle spinning nuclear magnetic resonance (NMR) spectroscopy of C.

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Most kidney cancers display evidence of metabolic dysfunction but how this relates to cancer progression in humans is unknown. We used a multidisciplinary approach to infuse C-labeled nutrients during surgical tumour resection in over 70 patients with kidney cancer. Labeling from [U-C]glucose varies across cancer subtypes, indicating that the kidney environment alone cannot account for all metabolic reprogramming in these tumours.

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Background: Cancer is the leading cause of death for Hispanics in the USA. Screening and prevention reduce cancer morbidity and mortality.

Methods: This study administered a cross-sectional web-based survey to self-identified Hispanic residents in the state of Indiana to assess their cancer-related knowledge, beliefs, and behaviors, as well as to identify what factors might be associated with cancer screening and prevention.

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Kidneys play a central role in numerous disorders but current imaging methods have limited utility to probe renal metabolism. Hyperpolarized (HP) C magnetic resonance imaging is uniquely suited to provide metabolite-specific information about key biochemical pathways and it offers the further advantage that renal imaging is practical in humans. This study evaluated the feasibility of hyperpolarization examinations in a widely used model for analysis of renal physiology, the isolated kidney, which enables isolation of renal metabolism from the effects of other organs and validation of HP results by independent measurements.

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The concerted action of voltage-gated ion channels in the brain is fundamental in controlling neuronal physiology and circuit function. Ion channels often associate in multi-protein complexes together with auxiliary subunits, which can strongly influence channel expression and function and, therefore, neuronal computation. One such auxiliary subunit that displays prominent expression in multiple brain regions is the Dipeptidyl aminopeptidase-like protein 6 (DPP6).

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Advanced imaging technologies, large-scale metabolomics, and the measurement of gene transcripts or enzyme expression all enable investigations of intermediary metabolism in human patients. Complementary information about fluxes in individual metabolic pathways may be obtained by ex vivo C NMR of blood or tissue biopsies. Simple molecules such as C-labeled glucose are readily administered to patients prior to surgical biopsies, and C-labeled glycerol is easily administered orally to outpatients.

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The purpose of this qualitative study was to explore the challenges adolescents with inflammatory bowel disease (IBD) experience with disease self-management as expressed in an online Instagram social support community. Public Instagram posts between January and December 2019 were manually collected from an online IBD support community. To focus on adolescent self-management needs, only posts from Instagram users who (1) indicated they had inflammatory bowel disease, (2) were 13-24 years old, or were in middle school, high school, or college were collected.

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The TCA cycle is a central metabolic pathway for energy production and biosynthesis. A major control point of metabolic flux through the cycle is the decarboxylation of 2-ketoglutarate by the TCA cycle enzyme 2-ketoglutarate dehydrogenase (2-KGDH). In this project, we developed C labeled 2-ketoglutarate derivatives to monitor 2-KGDH activity in vivo.

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Background: Hyperpolarized (HP) [1-C]pyruvate cardiovascular magnetic resonance (CMR) imaging can visualize the uptake and intracellular conversion of [1-C]pyruvate to either [1-C]lactate or C-bicarbonate depending on the prevailing metabolic state. The aim of the present study was to combine an adenosine stress test with HP [1-C]pyruvate CMR to detect cardiac metabolism in the healthy human heart at rest and during moderate stress.

Methods: A prospective descriptive study was performed between October 2019 and August 2020.

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Contamination of per- and polyfluoroalkyl substances (PFAS) in water supplies will continue to have serious health and environmental consequences. Despite the importance of monitoring the concentrations of PFAS at potential sites of contamination and at treatment plants, there are few suitable and rapid on-site methods. Many nonconventional techniques do not possess the necessary selectivity and sensitivity to distinguish PFAS from other surface-active components and to quantify the low concentrations in real-world conditions.

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Background: Nurses comprise the largest portion of healthcare workers and are integral to the COVID-19 response. Twitter has become a popular platform for the public, including nurses, to engage in pandemic-related discourse.

Purpose: We sought to analyze the representation of the nursing profession and characterize nurses' experiences during the pandemic from tweets published in April 2020.

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Background: Empagliflozin, a sodium glucose cotransporter 2 inhibitor, is a medication to treat type 2 diabetes. The effect of empagliflozin in persons without diabetes has received less attention. Here we conducted a randomized, double-blind placebo-controlled clinical trial to examine the effect of empagliflozin on plasma triglycerides in obese non-diabetic adults.

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