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Nigel Turner

Publications and source records attributed to Nigel Turner.

24 records · Page 2Linked to original sources
PubMed2003

Greater effect of diet than exercise training on the fatty acid profile of rat skeletal muscle.

We determined the interaction of diet and exercise-training intensity on membrane phospholipid fatty acid (FA) composition in skeletal muscle from 36 female Sprague-Dawley rats. Animals were randomly divided into one of two dietary conditions: high-carbohydrate (64.0% carbohydrate by energy, n = 18) or high fat (78.1% fat by energy, n = 18). Rats in each diet condition were then allocated to one of three subgroups: control, which performed no exercise training; low-intensity (8 m/min) treadmill run training; or high-intensity (28 m/min) run training. All exercise-trained rats ran 1,000 m/session, 4 days/wk for 8 wk and were killed 48 h after the last training bout. Membrane phospholipids were extracted, and FA composition was determined in the red and white vastus lateralis muscles. Diet exerted a major influence on phospholipid FA composition, with the high-fat diet being associated with a significantly (P < 0.01) elevated ratio of n-6/n-3 FA for both red (2.7-3.2 vs. 1.0-1.1) and white vastus lateralis muscle (2.5-2.9 vs. 1.2). In contrast, alterations in FA composition as a result of either exercise-training protocol were only minor in comparison. We conclude that, under the present experimental conditions, a change in the macronutrient content of the diet was a more potent modulator of skeletal muscle membrane phospholipid FA composition compared with either low- or high-intensity treadmill exercise training.

Animals↗
PubMed2003

Docosahexaenoic acid (DHA) content of membranes determines molecular activity of the sodium pump: implications for disease states and metabolism.

The omega-3 polyunsaturate, docosahexaenoic acid (DHA), plays a number of biologically important roles, particularly in the nervous system, where it is found in very high concentrations in cell membranes. In infants DHA is required for the growth and functional development of the brain, with a deficiency resulting in a variety of learning and cognitive disorders. During adulthood DHA maintains normal brain function and recent evidence suggests that reduced DHA intake in adults is linked with a number of neurological disorders including schizophrenia and depression. Here we report a high positive correlation between the molecular activity (ATP min(-1)) of individual Na(+)K(+)ATPase units and the content of DHA in the surrounding membrane bilayer. This represents a fundamental relationship underlying metabolic activity, but may also represent a link between reduced levels of DHA and neurological dysfunction, as up to 60% of energy consumption in the brain is linked to the Na(+)K(+)ATPase enzyme.

Adult↗
PubMed2003

Modulation of Na,K-ATPase by phospholipids and cholesterol. II. Steady-state and presteady-state kinetics.

The effects of phospholipid acyl chain length (n(c)) and cholesterol on several partial reactions of Na,K-ATPase reconstituted into liposomes of defined lipid composition are described. This regards the E(1)/E(2) equilibrium, the phosphoenzyme level, and the K(+)-deocclusion reaction. In addition, the lipid effects on some steady-state properties were investigated. Finally, the effects of cholesterol on the temperature sensitivity of the phosphorylation and spontaneous dephosphorylation reactions were investigated. The fatty acid and cholesterol composition of the native Na,K-ATPase membrane preparation showed a remarkable similarity to the lipid composition known to support maximum hydrolytic capacity as determined from in vitro experiments. The main rate-determining step of the Na,K-ATPase reaction, the E(2) --> E(1) reaction, as well as several other partial reactions were accelerated by cholesterol. This regards the phosphorylation by ATP as well as the E(1) - P --> E(2)-P reaction. Moreover, cholesterol shifted the E(1)/E(2) equilibrium toward the E(1) conformation and increased the K(+)-deocclusion rate. Finally, cholesterol significantly affected the temperature sensitivity of the spontaneous dephosphorylation reaction and the phosphorylation by ATP. The effects of cholesterol were not completely equivalent to those induced by increasing the phospholipid acyl chain length, indicating that the cholesterol effects are not entirely caused by increasing the hydrophobic bilayer thickness, which indicates an additional mechanism of action on the Na,K-ATPase.

Animals↗
PubMed1999

Checkered Expectations: Predictors of Approval of Opening a Casino in the Niagara Community.

This paper reports on the findings of a survey prior to the opening of a casino in Niagara Falls, Ontario (N= 1002 adults) on approval of the casino, expectations regarding the impact of the casino, attitudes toward gambling, gambling behaviour, and demographic information. The respondents generally had a positive attitude towards gambling. The expectations of community impact clustered into 3 factors: negative social consequences (crimes, addiction), negative environmental consequences (litter, noise, traffic), and positive economic consequences (jobs, stores, income). The majority of respondents expected economic benefits from the casino as well as a decrease in the environmental quality of the city. Expectations regarding social problems were mixed with a majority expecting an increase in serious crimes, but only a minority expecting an increase in people on welfare. Covariance structure modelling revealed that a positive attitude towards gambling and expecting economic benefits were positively related to approval of the casino, and expecting social problems was negatively related to approval. Given that more than seven in ten respondents supported the opening of the casino, the expected economic benefits coupled with a generally positive attitude towards gambling, apparently outweighed concerns about problems associated with gambling.

Journal Article↗
PubMedDate not supplied

Achieving compliance with the European Working Time Directive in a large teaching hospital: a strategic approach.

This paper describes the strategy which achieved European Working Time Directive (EWTD) compliance at the Royal Free Hampstead NHS Trust in medicine and surgery. Compliance with EWTD regulations was assessed by diary card exercise, clinical care assessed through critical incident reports, electronic handover documents and nursing reports, training opportunities assessed by unit training directors, cost controls assessed by finance department analysis, and workload assessed by staff attendance on wards, in casualty and in theatres. There was a change in focus of care to a consultant-led, specialist registrar- (SpR-)driven service extending into evenings and on weekends, coupled with a move to a multi-skilled team for night cover, and to a move from traditional on-call shifts to a full shift system across both medicine and surgery. Compliance with the EWTD was achieved whilst maintaining good standards of clinical care, ensuring training opportunities for doctors in training, controlling payroll costs, removing the need for locums, and reducing workload for both junior doctors and consultants.

England↗