Publications by authors named "DG Burke"

Laboratory testing methods to confirm the identity of meat products and eliminate food fraud regularly rely on PCR amplification of extracted DNA, with most published assays detecting mitochondrial sequences, providing sensitive presence/absence results. By targeting single-copy nuclear targets instead, relative quantification measurements are achievable, providing additional information on the proportions of meat species detected. In this Methods paper, new assays for horse, donkey, duck, kangaroo, camel, water buffalo and crocodile have been developed to expand the range of species that can be quantified, and a previously published reference assay targeting the myostatin gene has been modified to include marsupials and reptiles.

View Article and Find Full Text PDF

Fabry disease (FD) is caused by mutations in the gene that encodes lysosomal α-galactosidase-A (α-gal-A). A number of pathogenic mechanisms have been proposed and these include loss of mitochondrial respiratory chain activity. For FD, gene therapy is beginning to be applied as a treatment.

View Article and Find Full Text PDF

Digital polymerase chain reaction (dPCR) is increasingly being adopted by reference material producers and metrology institutes for value assignment, and for homogeneity and stability studies of nucleic acid reference materials. A reference method procedure should fulfill several requirements, and the uncertainty and biases should be completely understood. A bias in target concentration when inaccurate droplet volume is used in the droplet dPCR measurement equation has previously been documented.

View Article and Find Full Text PDF

Background: Cystic Fibrosis (CF) is an autosomal recessive disease that affects the function of a number of organs, principally the lungs, but also the gastrointestinal tract. The manifestations of cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction in the gastrointestinal tract, as well as frequent antibiotic exposure, undoubtedly disrupts the gut microbiota. To analyse the effects of CF and its management on the microbiome, we compared the gut microbiota of 43 individuals with CF during a period of stability, to that of 69 non-CF controls using 454-pyrosequencing of the 16S rRNA gene.

View Article and Find Full Text PDF

Parkinson's disease (PD) is a neurodegenerative disorder caused by loss of dopaminergic and serotoninergic signalling. A number of pathogenic mechanisms have been implicated including loss of mitochondrial function at the level of complex I, and lysosomal metabolism at the level of lysosomal glucocerebrosidase (GBA1). In order to investigate further the potential involvement of complex I and GBA1 in PD, we assessed the impact of loss of respective enzyme activities upon dopamine and serotonin turnover.

View Article and Find Full Text PDF

Clostridium difficile is an anaerobic Gram-positive, spore-forming, toxin-producing bacillus transmitted among humans through the faecal-oral route. Despite increasing carriage rates and the presence of C. difficile toxin in stool, patients with CF rarely appear to develop typical manifestations of C.

View Article and Find Full Text PDF

Digital polymerase chain reaction (dPCR) is potentially a primary method for quantifying target DNA regions in a background of nontarget material and is independent of external calibrators. Accurate dPCR measurements require single-molecule detection by conventional PCR assays that may be subject to bias due to inhibition, interference, or sequence-derived PCR inefficiency. Elimination or control of such biases is essential for validation of PCR assays, but this may require a substantial investment in resources.

View Article and Find Full Text PDF

Lysosomal glucocerebrosidase (GBA1) deficiency is causative for Gaucher disease. Not all individuals with GBA1 mutations develop neurological involvement raising the possibility that other factors may provide compensatory protection. One factor may be the activity of the non-lysosomal β-glucosidase (GBA2) which exhibits catalytic activity towards glucosylceramide and is reported to be highly expressed in brain tissue.

View Article and Find Full Text PDF

The purpose was to determine if creatine supplementation, consumed immediately before and immediately after exercise, with different dosing frequency (i.e., 2 or 3 d wk) could enhance the gains in muscle size and strength from resistance training (RT) in young adults.

View Article and Find Full Text PDF

The increased presence of 5-methycytosine at gene promoter regions may be diagnostic of cancer. However, there are many stages in the measurement of gene promoter 5-methylcytosine content where inaccuracies may occur, and this may prevent the use of these measurements for diagnostic or prognostic purposes. A high accuracy LC-MS system was developed for measuring the degree of methylation in two 100 base pair amplicons generated by the polymerase chain reaction (PCR) and in which 5-methylcytidine had been synthetically incorporated.

View Article and Find Full Text PDF

In response to the sovereign requirement for national standards the National Measurement Institute, Australia (NMIA) has developed a measuring system using isotope dilution mass spectrometry (IDMS) to certify forensic aqueous ethanol solutions. NMIA participated in an international study, CCQM-K27, organized under the auspices of the International Committee for Weights and Measures to compare our measuring system with the techniques being used for certifying aqueous ethanol solutions in other metrology institutes. This comparison provided objective evidence that the measuring system developed was fit for the purpose of certifying aqueous ethanol solutions that ranged in concentration from 0.

View Article and Find Full Text PDF

Muscle and strength loss will occur during periods of physical inactivity and immobilization. Creatine supplementation may have a favorable effect on muscle mass and strength independently of exercise. The purpose of this study was to determine the effects of creatine supplementation on upper limb muscle mass and muscle performance after immobilization.

View Article and Find Full Text PDF

Various methods have been developed for quantitative analysis of DNA methylation. However, there is currently no reference analysis system regarding DNA methylation with which other analytical approaches can be compared and evaluated. A standard measurement system that includes reference methods and reference materials may improve comparability and credibility of data obtained from different analytical environments.

View Article and Find Full Text PDF

The purpose of this study was to compare changes in muscle insulin-like growth factor-I (IGF-I) content resulting from resistance-exercise training (RET) and creatine supplementation (CR). Male (n=24) and female (n=18) participants with minimal resistance-exercise-training experience (=1 year) who were participating in at least 30 min of structured physical activity (i.e.

View Article and Find Full Text PDF

Highly accurate measurements of the amount of substance of organic molecules in a test material can be obtained using exactly matched calibration solutions and internal standards that are labeled with stable isotope atoms by measuring the amount ratio of analyte to internal standard using mass spectrometry. Estimating the uncertainty of quantitative measurements of organic molecules is a means of evaluating accuracy and of establishing traceability to the International System of Units (SI) and requires a measurement function that fully describes the measuring system. This paper presents the derivation of the equation (measurement function) that describes this complete measurement after the internal standard has equilibrated with the test material matrix.

View Article and Find Full Text PDF

Changes in muscle mass and strength will vary, depending on the volume and frequency of training. The purpose of this study was to determine the effect of short-term equal-volume resistance training with different workout frequency on lean tissue mass and muscle strength. Twenty-nine untrained volunteers (27-58 years; 23 women, 6 men) were assigned randomly to 1 of 2 groups: group 1 (n = 15; 12 women, 3 men) trained 2 times per week and performed 3 sets of 10 repetitions to fatigue for 9 exercises, group 2 (n = 14; 11 women, 3 men) trained 3 times per week and performed 2 sets of 10 repetitions to fatigue for 9 exercises.

View Article and Find Full Text PDF

The purpose was to compare changes in lean tissue mass, strength, and myofibrillar protein catabolism resulting from combining whey protein or soy protein with resistance training. Twenty-seven untrained healthy subjects (18 female, 9 male) age 18 to 35 y were randomly assigned (double blind) to supplement with whey protein (W; 1.2 g/kg body mass whey protein + 0.

View Article and Find Full Text PDF

Aim: Creatine monohydrate supplementation is beneficial for enhancing high-intensity exercise performance, especially activities that involve repeated sprints. Creatine monohydrate supplementation is common in ice-hockey players. The purpose of this study was to determine the effect of creatine monohydrate supplementation on sprint skating performance in Junior B and collegiate ice-hockey players.

View Article and Find Full Text PDF

Objective: To present several modifications of the standard sit-and-reach protocol.

Background: Many exercises designed to increase strength and aerobic capacity tend to decrease the flexibility of the erector spinae and hamstrings musculature. Less-than-ideal flexibility in these soft tissues may increase the risk of injury during training, competition, or activities of daily living.

View Article and Find Full Text PDF

Our purpose was to determine the effects of creatine supplementation combined with resistance training on bone mineral content and density in older men. Twenty-nine older men (age 71 y) were randomized (double blind) to receive creatine (0.3 g/kg creatine for 5 d and 0.

View Article and Find Full Text PDF

Creatine, which is increasingly being used as an oral supplement, is naturally present in the body. Studies on the fate of a particular dose of creatine require that the creatine be labeled, and for studies in humans the use of a stable isotopic label is desirable. The concentrations of total creatine and total creatinine were determined using HPLC.

View Article and Find Full Text PDF

The purpose of this study was to examine the effect of a 5-day creatine (CR) supplementation period on red blood cell (RBC) CR uptake in vegetarian and nonvegetarian young women. Blood samples were collected from lacto-ovo vegetarians (VG, n = 6, age 21.8 +/- 1.

View Article and Find Full Text PDF

Unlabelled: Muscles exercised before creatine (Cr) supplementation have a greater elevation of intramuscular Cr than nonexercised muscles.

Purpose: To determine whether preferential increase of muscle thickness could be achieved by ingesting Cr immediately after exercise of specific muscles over 6 wk. Another purpose was to determine if the increase in lean tissue mass (LTM) with Cr supplementation is greater in males than females.

View Article and Find Full Text PDF

The authors previously found that creatine (Cr) combined with 12 weeks of resistance training enhanced muscle strength and endurance and lean tissue mass (LTM) in older men. Their purpose in this study was to assess these variables with cessation of Cr combined with 12 weeks of reduced training (33% lower volume) in a subgroup of these men (n = 8, 73 years old) compared with 5 men (69 years old) who did not receive Cr. Strength (1-repetition maximum [1-RM]), endurance (maximum number of repetitions over 3 sets at 70-80% 1-RM), and LTM (dual-energy X-ray absorptiometry) were assessed before and after 12 weeks of Cr cessation combined with reduced-volume training.

View Article and Find Full Text PDF