Publications by authors named "Andrew Chappell"

15 Publications

  • Page 1 of 1

Pholedrine is a marker of direct disposal of methamphetamine.

Sci Total Environ 2021 Aug 30;782:146839. Epub 2021 Mar 30.

Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide 5001, South Australia, Australia. Electronic address:

Consumption of methamphetamine has primarily been estimated in wastewater-based epidemiology by measuring the parent compound. However, this could lead to overestimation when methamphetamine is directly disposed into the sewer system. In this respect, it would be advantageous to measure a specific metabolite of methamphetamine instead. We identified 4-hydroxymethamphetamine (pholedrine) as a potential marker. Stability experiments were performed in both filtered and unfiltered wastewater. Correlations with relative loads in wastewater were used to establish its potential as a marker of direct disposal of methamphetamine, or even as a wastewater-based epidemiology biomarker of methamphetamine consumption. This study then investigated the use of pholedrine in combination with methamphetamine to better detect direct disposal events and its potential as a marker of methamphetamine consumption. Examples from both South Australia and New Zealand exemplify the use of pholedrine to identify potential instances of direct disposal of methamphetamine.
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http://dx.doi.org/10.1016/j.scitotenv.2021.146839DOI Listing
August 2021

International snapshot of new psychoactive substance use: Case study of eight countries over the 2019/2020 new year period.

Water Res 2021 Apr 3;193:116891. Epub 2021 Feb 3.

Health and Biomedical Innovation, UniSA: Clinical and Health Sciences, University of South Australia, Adelaide 5001, South Australia, Australia. Electronic address:

There is considerable concern around the use of new psychoactive substances (NPS), but still little is known about how much they are really consumed. Analysis by forensics laboratories of seized drugs and post-mortem samples as well as hospital emergency rooms are the first line of identifying both 'new' NPS and those that are most dangerous to the community. However, NPS are not necessarily all seized by law enforcement agencies and only substances that contribute to fatalities or serious afflictions are recorded in post-mortem and emergency room samples. To gain a better insight into which NPS are most prevalent within a community, complementary data sources are required. In this work, influent wastewater was analysed from 14 sites in eight countries for a variety of NPS. All samples were collected over the 2019/2020 New Year period, a time which is characterized by celebrations and parties and therefore a time when more NPS may be consumed. Samples were extracted in the country of origin following a validated protocol and shipped to Australia for final analysis using two different mass spectrometric strategies. In total, more than 200 were monitored of which 16 substances were found, with geographical differences seen. This case study is the most comprehensive wastewater analysis study ever carried out for the identification of NPS and provides a starting point for future, ongoing monitoring of these substances.
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http://dx.doi.org/10.1016/j.watres.2021.116891DOI Listing
April 2021

The foot-health of people with diabetes in regional and rural Australia: baseline results from an observational cohort study.

J Foot Ankle Res 2019 5;12:56. Epub 2019 Dec 5.

1La Trobe Rural Health School, La Trobe University, PO Box 199, Bendigo, 3552 Australia.

Background: There is limited Australian epidemiological research that reports on the foot-health characteristics of people with diabetes, especially within rural and regional settings. The objective of this study was to explore the associations between demographic, socio-economic and diabetes-related variables with diabetes-related foot morbidity in people residing in regional and rural Australia.

Methods: Adults with diabetes were recruited from non-metropolitan Australian publicly-funded podiatry services. The primary variable of interest was the University of Texas diabetic foot risk classification designated to each participant at baseline. Independent risk factors for diabetes-related foot morbidity were identified using multivariable analysis.

Results: Eight-hundred and ninety-nine participants enrolled, 443 (49.3%) in Tasmania and 456 (50.7%) in Victoria. Mean age was 67 years (SD 12.7), 9.2% had type 1 diabetes, 506 (56.3%) were male, 498 (55.4%) had diabetes for longer than 10 years and 550 (61.2%) either did not know the ideal HbA1c target or reported that it was ≥7.0. A majority had peripheral neuropathy or worse foot morbidity (61.0%). Foot morbidity was associated with male sex (OR 2.42, 95% CI 1.82-3.22), duration of diabetes > 20 years (OR 3.25, 95% CI 2.22-4.75), and Tasmanian residence (OR 3.38, 95% CI 2.35-4.86).

Conclusions: A high proportion of the regional Australian clinical population with diabetes seen by the publicly-funded podiatric services in this study were at high risk of future limb threatening foot morbidity, and participants residing in Northern Tasmania are more likely to have worse diabetes-related foot morbidity than those from regional Victoria. Service models should be reviewed to ensure that diabetes-related foot services are appropriately developed and resourced to deliver interdisciplinary evidence-based care.
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http://dx.doi.org/10.1186/s13047-019-0366-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6896347PMC
April 2020

The effects of a sleep/recovery supplement: 'Night Time Recharge' on sleep parameters in young adults.

Nutr Health 2019 Dec 12;25(4):265-274. Epub 2019 Sep 12.

School of Pharmacy and Life Science, Robert Gordon University, Aberdeen, UK.

Background: Concentrated cherry juice reportedly contains melatonin which, in turn, has been highlighted as an important regulator in initiating sleep.

Aim: The present investigation aims to clarify whether Night Time Recharge (NTR), a marketed sleep aid containing cherry extract, improves key sleep parameters in young, active adults with mildly poor sleep.

Methods: A double-blind, randomized, placebo-controlled, cross-over study design was employed. Twenty participants (nine female) consumed either NTR or a placebo for seven days. Accelerometers were used to assess sleep quality and physical activity levels. Urinary levels of 6-sulphatoxymelatonin (6-SMT), a marker of melatonin synthesis, was assessed via enzyme-linked immunosorbent assay.

Results: 6-SMT levels increased following NTR treatment (28.95 ng/ml) compared with placebo (4.0 ng/ml) ( < 0.001). There was also a significant difference ( = 0.047) in dietary tryptophan consumption during the NTR treatment (1236 mg) versus placebo (1149 mg). No trace of melatonin was detected from our analysis of the supplement. NTR had no significant effect on any sleep parameters with the exception of sleep latency ( = 0.001).

Conclusions: As chemical analysis of NTR by liquid-chromatography mass-spectrometry identified no detectable melatonin, the tryptophan content of the supplement is a likely reason for improvement in sleep latency. These results are in contrast to previous studies which have found a positive effect on sleep following cherry supplementation. Future work should focus on sleep latency and investigating whether cherry juice is effective in participants with problems in initiating sleep.
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http://dx.doi.org/10.1177/0260106019875911DOI Listing
December 2019

Citrulline Malate Fails to Improve German Volume Training Performance in Healthy Young Men and Women.

J Diet Suppl 2020 21;17(3):249-260. Epub 2018 Nov 21.

Food and Nutrition Group, Sheffield School of Business, Sheffield Hallam University, Sheffield, UK.

Citrulline malate (CM) is purported to buffer lactic acid, enhance oxygen delivery, and attenuate muscle soreness. Anaerobic exercise trials with CM have produced conflicting results. The aim of the current investigation was to test the efficacy of CM on resistance training (RT) with the hypothesis that CM would improve performance. A double-blind, counter-balanced, randomized control trial was utilized to assess the effects of CM on RT. Nineteen participants (8 female) (25.7 ± 7.7 years), regularly engaged in RT, consumed either 8 g of CM (1.1:1 ratio) or a placebo (6 g citric acid). Participants attempted to perform a German Volume Training (GVT) protocol comprising 10 sets of 10 repetitions of barbell curls at 80% of their one repetition maximum. Repeated ANOVA suggested no effect of CM on RT performance (treatment × time × order  = .217). There was no difference ( = .320) in the total number of reps over the 10 sets (CM median = 57, IQR 45-73; placebo median = 61, IQR 51-69). Blood lactate and creatine kinase did not differ between CM and placebo ( > .05). Finally, total muscle soreness was reduced significantly in CM compared to placebo (treatment × time × order  = .004). These results require corroboration; an ergogenic benefit is yet to be established, and weight trainers should exercise caution when assessing the efficacy of CM. Future research should focus on the potential effects of loading doses of CM.
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http://dx.doi.org/10.1080/19390211.2018.1513433DOI Listing
October 2020

Nutritional Peak Week and Competition Day Strategies of Competitive Natural Bodybuilders.

Sports (Basel) 2018 Oct 24;6(4). Epub 2018 Oct 24.

Food and Nutrition Group, Sheffield School of Business, Sheffield Hallam University, Howard St. Sheffield S1 1WB, UK.

Bodybuilders utilize peaking strategies in a bid to fine-tune their aesthetics for competition day. The most prevalent peaking strategies utilized by natural bodybuilders are unreported in the current literature. Eighty-one (M-59, F-22) natural bodybuilders were recruited from competitions during the 2016 and 2017 British Natural Bodybuilder Federation seasons. Competitors completed a 34-item questionnaire designed to investigate peaking and contest day strategies. The questionnaire listed commonly utilized peaking strategies and provided additional space for qualitative information. Analysis of the data indicated that carbohydrate (CHO), water, and sodium manipulation were the most commonly utilized peaking strategies. The consumption of high glycemic index CHO was the most common competition day strategy. Only 6.2% of competitors reported following their regular diet the week prior to competition. The CHO manipulation strategies followed were similar to classical CHO loading, whereby bodybuilders attempt to maximize muscle glycogen concentrations. Furthermore, bodybuilders attempted to remove superfluous water by exploiting the diuretic/polyuria effect associated with water loading/restriction. The potentially deleterious effects of peaking on bodybuilders' health is considered and the efficacy of these strategies to enhance appearance is discussed. The findings of the present investigation are likely to be of interest to bodybuilders and their coaches.
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http://dx.doi.org/10.3390/sports6040126DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6315482PMC
October 2018

Citrulline malate supplementation does not improve German Volume Training performance or reduce muscle soreness in moderately trained males and females.

J Int Soc Sports Nutr 2018 Aug 10;15(1):42. Epub 2018 Aug 10.

Food and Nutrition group, Sheffield Business School, Sheffield Hallam University, Stoddard Building, City Campus, Sheffield, UK.

Background: Use of supplements to aid performance is common practice amongst recreationally active individuals, including those without a sufficient evidence base. This investigation sought to assess whether acute supplementation with 8 g of citrulline malate (CM) (1.11: 1 ratio) would improve anaerobic performance.

Methods: A randomised double blind placebo control trial was employed, using a counterbalanced design. We recruited recreationally active men and women to take part in an isokinetic chair protocol, based on German Volume Training (GVT) whereby participants attempted to perform 10 sets of 10 repetitions against a force representing 70% of their peak concentric force.

Results: The number of repetitions achieved over the course of the GVT was 94.0 ± 7.9 and 90.9 ± 13.9 for placebo and CM respectively. There was no significant difference between the placebo and CM treatment for number of repetitions (P = 0.33), isometric (P = 0.60), concentric (P = 0.38), or eccentric (P = 0.65) peak force following the GVT. Total muscle soreness was significantly higher in the CM compared to the placebo treatment following the GVT protocol over 72 h (P = 0.01); although this was not accompanied by a greater workload/number of repetitions in the CM group.

Conclusions: We conclude that an acute dose of CM does not significantly affect anaerobic performance using an isokinetic chair in recreational active participants. Practical implications include precaution in recommending CM supplementation. Coaches and athletes should be aware of the disparity between the chemical analyses of the products reviewed in the present investigation versus the manufacturers' claims.
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http://dx.doi.org/10.1186/s12970-018-0245-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6086018PMC
August 2018

Analysis and Assessment of Exposure to Selected Phthalates Found in Children's Toys in Christchurch, New Zealand.

Int J Environ Res Public Health 2018 01 25;15(2). Epub 2018 Jan 25.

Tox-Logic Consulting, LLC, Petaluma, CA 94954, USA.

Internationally several phthalates are subject to regulatory control regarding maximum allowable concentrations in children's toys. Such regulation is not in place in New Zealand. Phthalates have been associated with developmental toxicity and endocrine disruption. We determined the concentration of seven phthalates in children's toys purchased in Christchurch, New Zealand. These results provided data for an exposure assessment deriving Hazard Indices (HI) for oral and dermal exposure routes in children, based on the concentration of mixtures of phthalates shown by the EU to produce either reproductive/developmental or hepatotoxic effects. Of the 49 toys analyzed, 65% contained at least one phthalate at a concentration of >0.1% by mass; and 35% contained multiple-phthalates at individual concentrations of >0.1%. A HI of 3.4 was derived for the combined exposures to the four phthalates associated with reproductive and developmental effects. A HI of 0.3 was derived for the group of phthalates associated with hepatotoxic effects. Five phthalates were detected at levels exceeding the EU regulatory limit of 0.1% by mass. Risk assessment calculations indicate that, using realistic exposure scenarios, the worst-case combined exposure to phthalates associated with developmental toxicity exceeded a HI of 1 so may cause adverse developmental effects.
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http://dx.doi.org/10.3390/ijerph15020200DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5858269PMC
January 2018

Identifying avian sources of faecal contamination using sterol analysis.

Environ Monit Assess 2015 Oct 14;187(10):625. Epub 2015 Sep 14.

Institute of Environmental Science and Research Limited, Christchurch Science Centre, PO Box 29-181, Christchurch, New Zealand.

Discrimination of the source of faecal pollution in water bodies is an important step in the assessment and mitigation of public health risk. One tool for faecal source tracking is the analysis of faecal sterols which are present in faeces of animals in a range of distinctive ratios. Published ratios are able to discriminate between human and herbivore mammal faecal inputs but are of less value for identifying pollution from wildfowl, which can be a common cause of elevated bacterial indicators in rivers and streams. In this study, the sterol profiles of 50 avian-derived faecal specimens (seagulls, ducks and chickens) were examined alongside those of 57 ruminant faeces and previously published sterol profiles of human wastewater, chicken effluent and animal meatwork effluent. Two novel sterol ratios were identified as specific to avian faecal scats, which, when incorporated into a decision tree with human and herbivore mammal indicative ratios, were able to identify sterols from avian-polluted waterways. For samples where the sterol profile was not consistent with herbivore mammal or human pollution, avian pollution is indicated when the ratio of 24-ethylcholestanol/(24-ethylcholestanol + 24-ethylcoprostanol + 24-ethylepicoprostanol) is ≥0.4 (avian ratio 1) and the ratio of cholestanol/(cholestanol + coprostanol + epicoprostanol) is ≥0.5 (avian ratio 2). When avian pollution is indicated, further confirmation by targeted PCR specific markers can be employed if greater confidence in the pollution source is required. A 66% concordance between sterol ratios and current avian PCR markers was achieved when 56 water samples from polluted waterways were analysed.
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http://dx.doi.org/10.1007/s10661-015-4800-3DOI Listing
October 2015

Examining Impulse-Variability in Kicking.

Motor Control 2016 Jul 26;20(3):222-32. Epub 2015 May 26.

Los Angeles Angels Baseball Club, Jonestown, TX.

This study examined variability in kicking speed and spatial accuracy to test the impulse-variability theory prediction of an inverted-U function and the speed-accuracy trade-off. Twenty-eight 18- to 25-year-old adults kicked a playground ball at various percentages (50-100%) of their maximum speed at a wall target. Speed variability and spatial error were analyzed using repeated-measures ANOVA with built-in polynomial contrasts. Results indicated a significant inverse linear trajectory for speed variability (p < .001, η2= .345) where 50% and 60% maximum speed had significantly higher variability than the 100% condition. A significant quadratic fit was found for spatial error scores of mean radial error (p < .0001, η2 = .474) and subject-centroid radial error (p < .0001, η2 = .453). Findings suggest variability and accuracy of multijoint, ballistic skill performance may not follow the general principles of impulse-variability theory or the speed-accuracy trade-off.
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http://dx.doi.org/10.1123/mc.2014-0062DOI Listing
July 2016

Fish oil supplementation reduces markers of oxidative stress but not muscle soreness after eccentric exercise.

Int J Sport Nutr Exerc Metab 2014 Apr 13;24(2):206-14. Epub 2013 Nov 13.

Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom.

Due to the potential anti-inflammatory properties of fish-derived long chain n-3 fatty acids, it has been suggested that athletes should regularly consume fish oils-although evidence in support of this recommendation is not clear. While fish oils can positively modulate immune function, it remains possible that, due to their high number of double bonds, there may be concurrent increases in lipid peroxidation. The current study aims to investigate the effect of fish oil supplementation on exercise-induced markers of oxidative stress and muscle damage. Twenty males underwent a 6-week double-blind randomized placebo-controlled supplementation trial involving two groups (fish oil or placebo). After supplementation, participants undertook 200 repetitions of eccentric knee contractions. Blood samples were taken presupplementation, postsupplementation, immediately, 24, 48, and 72 hr postexercise and muscle soreness/maximal voluntary contraction (MVC) assessed. There were no differences in creatine kinase, protein carbonyls, endogenous DNA damage, muscle soreness or MVC between groups. Plasma thiobarbituric acid reactive substances (TBARS) were lower (p < .05) at 48 and 72 hr post exercise and H2O2 stimulated DNA damage was lower (p < .05) immediately postexercise in the fish oil, compared with the control group. The current study demonstrates that fish oil supplementation reduces selected markers of oxidative stress after a single bout of eccentric exercise.
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http://dx.doi.org/10.1123/ijsnem.2013-0081DOI Listing
April 2014

Electromyographic amplitude vs. concentric and eccentric squat force relationships for monoarticular and biarticular thigh muscles.

J Strength Cond Res 2014 Feb;28(2):328-38

Human Performance Laboratory, Department of Health, Exercise, and Sport Sciences, Texas Tech University, Lubbock, Texas.

This study examined the linearity of the electromyographic (EMG) amplitude vs. concentric and eccentric squat force relationships for monoarticular and biarticular thigh muscles. Fourteen resistance-trained men (mean age ± SD: 22 ± 2 years; estimated thigh muscle cross-sectional area: 221.9 ± 22.7 cm) performed concentric and eccentric squats using a novel testing device from 10 to 90% of their maximum average force. Surface EMG signals were detected from the right vastus lateralis, rectus femoris, and biceps femoris. Linear regression was used to examine the relationships between EMG amplitude and force, and repeated measures analyses of variance were used to assess differences among the muscles. Moderate-to-high coefficients of determination were found for the vastus lateralis for both concentric and eccentric testings (r = 0.587-0.992). For the biceps femoris, the mean linear slope coefficient was significantly greater for concentric vs. eccentric testing (0.044 vs. 0.013 μV RMS·N; p = 0.002; effect size = 1.44). Although EMG amplitude for the vastus lateralis and rectus femoris increased with changes in eccentric force output, the electrical activity of the biceps femoris remained stable. These results demonstrated that the EMG amplitude vs. force relationships for the vastus lateralis were linear, despite the fact that force production during the squat is related to the activation of muscles that must simultaneously function as agonists and antagonists. Our findings for eccentric force testing are in agreement with investigations showing reduced hip extensor activity during concurrent extension at the hip and knee joints.
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http://dx.doi.org/10.1519/JSC.0b013e3182a1f434DOI Listing
February 2014

Osteonecrosis of the femoral head following medullary nailing of the femur in an adult.

Acta Orthop Belg 2007 Apr;73(2):258-62

Western Infirmary, Glasgow, United Kingdom.

The femoral head receives the majority of its blood supply via branches of the medial femoral circumflex artery, whose course runs across the piriformis fossa and along the superior aspect of the femoral neck. Cadaveric studies have demonstrated damage to the medial femoral circumflex artery in cases where the piriformis fossa was the entry point for intramedullary nailing. Although well recognised in children, osteonecrosis of the femoral head after intramedullary nailing has exceptionally been reported in adults. We present a case of osteonecrosis of the femoral head post-epiphyseal closure following IM nailing for a femoral fracture in a 22-year-old Caucasian adult.
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April 2007

Traumatic cervical hematomyelia: report of a rare spinal cord injury without radiographic abnormality.

J Trauma 2008 Oct;65(4):938-41

Department of Orthopaedics and Trauma, Inverclyde Royal Hospital, Greenock, Scotland, United Kingdom.

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http://dx.doi.org/10.1097/01.ta.0000197909.10358.0fDOI Listing
October 2008

Structural elements required for association of the Saccharomyces cerevisiae telomerase RNA with the Est2 reverse transcriptase.

Mol Cell Biol 2004 Sep;24(17):7720-36

Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.

Telomere synthesis in most organisms depends on the action of the telomerase enzyme, which contains an RNA subunit that is stably associated with the reverse transcriptase subunit as well as additional telomerase proteins. In the budding yeast Saccharomyces cerevisiae, several structural domains that are responsible for mediating protein interactions with the telomerase RNA TLC1 have been identified. We report here the identification and characterization of a TLC1 stem-loop that is required for its interaction with the Est2 reverse transcriptase protein. This hairpin, which does not contain any bulges in the duplex stem that commonly mediate protein-RNA interaction, appears to be a part of a larger structure, as nucleotides immediately to either side of this stem-loop contribute to the interaction of TLC1 with the Est2 protein. Surprisingly, replacement of a 95-nucleotide region of the yeast telomerase RNA that is required for Est2 interaction with a 39-nucleotide pseudoknot from a distantly related telomerase RNA results in a functional telomerase enzyme. These findings suggest that the ability of the budding yeast reverse transcriptase to associate with the telomerase RNA depends on a highly structured region rather than specific sequence elements.
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http://dx.doi.org/10.1128/MCB.24.17.7720-7736.2004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC507002PMC
September 2004