Publications by authors named "Purcell H"

Objective: Obesity continues to be a major problem, despite known treatment strategies such as lifestyle modifications, pharmaceuticals, and surgical options, necessitating the development of novel weight loss approaches. The naturally occurring fatty acid, 10,12 conjugated linoleic acid (10,12 CLA), promotes weight loss by increasing fat oxidation and browning of white adipose tissue, leading to increased energy expenditure in obese mice. Coincident with weight loss, 10,12 CLA also alters the murine gut microbiota by enriching for microbes that produce short chain fatty acids (SCFAs), with concurrent elevations in fecal butyrate and plasma acetate.

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Metabolomics has been used extensively to capture the exposome. We investigated whether prospectively measured metabolites provided predictive power beyond well-established risk factors among 758 women with adjudicated cancers [ = 577 breast (BC) and = 181 colorectal (CRC)] and = 758 controls with available specimens (collected mean 7.2 years prior to diagnosis) in the Women's Health Initiative Bone Mineral Density subcohort.

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In a context where pessimistic survival perceptions have been widespread as a result of the HIV/AIDS epidemic (Fig. 1 ), we study vaccine uptake and other health behaviors during the recent COVID-19 pandemic. Leveraging a longitudinal cohort study in rural Malawi that has been followed for up to 25 y, we document that a 2017 mortality risk information intervention designed to reduce pessimistic mortality perceptions (Fig.

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The pathogenesis of exercise intolerance and persistent fatigue which can follow an infection with the SARS-CoV-2 virus ("long COVID") is not fully understood. Cases were recruited from a long COVID clinic (N = 32; 44 ± 12 years; 10 (31%) men), and age-/sex-matched healthy controls (HC) (N = 19; 40 ± 13 years; 6 (32%) men) from University College London staff and students. We assessed exercise performance, lung and cardiac function, vascular health, skeletal muscle oxidative capacity, and autonomic nervous system (ANS) function.

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Microcystin-producing cyanobacterial blooms are a global issue threatening drinking water supplies and recreation on lakes and beaches. Direct measurement of microcystins is the only way to ensure waters have concentrations below guideline concentrations; however, analyzing water for microcystins takes several hours to days to obtain data. We tested LightDeck Diagnostics' bead beater cell lysis and two versions of the quantification system designed to give microcystin concentrations within 20 min and compared it to the standard freeze-thaw cycle lysis method and ELISA quantification.

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Background: Strategies to increase cellular NAD (oxidized nicotinamide adenine dinucleotide) level have prevented cardiac dysfunction in multiple models of heart failure, but molecular mechanisms remain unclear. Little is known about the benefits of NAD-based therapies in failing hearts after the symptoms of heart failure have appeared. Most pretreatment regimens suggested mechanisms involving activation of sirtuin, especially Sirt3 (sirtuin 3), and mitochondrial protein acetylation.

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Background We showed that Beclin-1-dependent autophagy protects the heart in young and adult mice that underwent endotoxemia. Herein, we compared the potential therapeutic effects of Beclin-1 activating peptide, TB-peptide, on endotoxemia-induced cardiac outcomes in young adult and aged mice. We further evaluated lipopolysaccharide (lipopolysaccharide)-induced and TB-peptide treatment-mediated alterations in myocardial metabolism.

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Introduction: Post-COVID-19 complications require simultaneous characterisation and management to plan policy and health system responses. We describe the 12-month experience of the first UK dedicated post-COVID-19 clinical service to include hospitalised and non-hospitalised patients.

Methods: In a single-centre, observational analysis, we report the demographics, symptoms, comorbidities, investigations, treatments, functional recovery, specialist referral and rehabilitation of 1325 individuals assessed at the University College London Hospitals post-COVID-19 service between April 2020 and April 2021, comparing by referral route: posthospitalised (PH), non-hospitalised (NH) and post emergency department (PED).

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The quality of East African coffee beans has been significantly reduced by a flavor defect known as potato taste defect (PTD) due to the presence of 2-isopropyl-3-methoxypyrazine (IPMP) and 2-isobutyl-3-methoxypyrazine (IBMP). Therefore, the aims of this study were to determine the correlation between these methoxypyrazines and the severity of odor attributed to PTD and discover additional analytes that may be correlated with PTD using Fisher ratio analysis, a supervised discovery-based data analysis method. Specialty ground roasted coffees from East Africa were classified as clean (i.

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Significance: A new device attached to a smartphone was created for objective vision screening of young children including infants and newborns. The device is compact, lightweight, portable, cost-effective, and easy to operate. Therefore, it is suitable for screening large numbers of children in clinical settings, schools, and communities.

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Screening for sexually transmitted infections (STIs) outside of traditional health-care facilities is limited by the privacy needed for sample collection. We explored the acceptability of privacy shelters for the self-collection of genital swabs and tested the use of privacy shelters during mobile STI screening. Attendees ≥14 years old at two outdoor community events completed a questionnaire that assessed participant characteristics, health-care access, and rating of acceptability of self-collecting penile or vaginal swabs in a privacy shelter and four other private spaces: portable restroom, health van, home, and doctor's office.

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This protocol was withdrawn in April 2016 as the author team was unable to progress to the final review stage. An editorial decision was taken not to pursue this title. The editorial group responsible for this previously published document have withdrawn it from publication.

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Religious factors are known to contribute to treatment adherence in different patient populations, and religious coping has been found to be particularly important to adolescents dealing with chronic diseases. Adherence to prescribed treatments slows disease progression and contributes to desirable outcomes in most patients, and, therefore, adherence-promoting interventions provided by chaplains could be beneficial to various patient populations. The current article describes a pilot study to test the feasibility of a theoretically and empirically based chaplain intervention to promote treatment adherence for adolescents with CF.

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Objective: Mitochondrial DNA (mtDNA) encodes the proteins of the electron transfer chain to produce adenosine triphosphate through oxidative phosphorylation, and is essential to sustain life. mtDNA is unique from the nuclear genome in so much as it is solely maternally inherited (non-mendelian patterning), and shows a relatively high rate of mutation due to the absence of error checking capacity. While it is generally assumed that most new mutations accumulate through the process of heteroplasmy, it is unknown whether mutations initiated in the mother are inherited, occur in utero, or occur and accumulate early in life.

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A child's chronic illness can lead parents to utilize different types of coping, including religious beliefs and practices. Previous studies have generally focused on life-shortening diagnoses. The present study explored parental use of faith when the diagnosis was not life-shortening, using grounded-theory qualitative methodology.

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Patent foramen ovale (PFO) is a common finding in adults. A PFO is associated with right to left shunting but its importance in the aetiology of hypoxia in early COPD remains uncertain, although it has not proved possible to demonstrate a role for PFOs in the aetiology of hypoxia in patients with Global Initiative for chronic Obstructive Lung Disease (GOLD) stage III/IV disease. We compared the characteristics of GOLD stage II patients with or without a PFO and assessed its impact on exercise performance.

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Background: Chronic heart failure is a major cause of morbidity and mortality worldwide. Diuretics are regarded as the first-line treatment for patients with congestive heart failure since they provide symptomatic relief. The effects of diuretics on disease progression and survival remain unclear.

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Coronary heart disease is the major cause of morbidity and mortality in industrialized countries, and its prevalence is predicted to grow as the population ages. Current drugs for chronic stable angina (such as beta-blockers, calcium-channel blockers, long- and short-acting nitrates, and potassium-channel activators) are often effective, either as monotherapy or in combination, but side effects and contraindications may limit their use. The "I(f)" (for "funny") channel, discovered in 1979, is expressed mainly in the membrane of pacemaker cells present in the sinus node, the atrioventricular node, the ventricular conduction pathways, and ventricular myocytes.

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Elevated resting heart rate is an independent cardiovascular risk factor and rate reduction is beneficial. It is not known whether reduction of heart rate per se can improve outcome. Studies of beta-blockers in post-myocardial infarction patients suggest that this may be the case, but beta-blockers, may be poorly tolerated or contraindicated.

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Background: Chronic heart failure is a major cause of morbidity and mortality world-wide. Diuretics are regarded as the first-line treatment for patients with congestive heart failure since they provide symptomatic relief. The effects of diuretics on disease progression and survival remain unclear.

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