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1.
BMC Sports Sci Med Rehabil ; 13(1): 58, 2021 May 28.
Article in English | MEDLINE | ID: mdl-34049581

ABSTRACT

BACKGROUND: Throughout the ecosystem of sport, women have been and continue to be underrepresented at all levels compared to men. The capacity of community-level sport is heavily reliant on the many non-player roles including governance, as well as administration, coaching and officiating. Recently there has been increased attention to improving the gender balance in sport. The aim of this study is to investigate the proportions of women engaged in non-playing roles in sport (2016-2018). METHODS: This study involved secondary analysis of the AusPlay survey, a national population survey, funded by Sport Australia. This study utilised data from people aged 15-years or older about their involvement in non-playing roles in sport, and their demographic data. Survey respondents were asked "During the last 12 months, have you been involved with any sports in a nonplaying role, such as official, coach, referee, administrator, etc?" Analysis of non-player role responses focussed specifically on the top four non-player role categories; coach, official, administrator and manager. Frequency analysis concentrated on the distribution of men and women involvement in a non-player capacity for the three years, with detailed analysis of the most recent year (2018). RESULTS: In this study of 61,578 Australians there was a higher proportion of men in non-player roles in sport compared to women, across each of the three years (2018: men 55 %, women 46 %). Involvement of women in coaching increased significantly from 38 % to 2016 to 44 % in 2018 (p < 0.001). The proportion of women involved in administration roles significantly decreased from a peak of 51 % in 2017 to 46 % in 2018 (p < 0.001). CONCLUSIONS: Aligned with strategic policy and investment strategies, there are gradual increased representation of women in non-playing sport, coaching roles. Women are still underrepresented in terms of coaches, officials and administrators, but are more likely to be managers. It is recommended that there is continued mentoring, identification and emphasising of female role models, and further strategies to increase female presence in non-playing roles. We recommend that future research, in line with appropriate gender and cultural-change theories, investigates and discusses the progress of gender equality throughout playing and non-playing role in sport.

2.
Glycobiology ; 31(5): 649-661, 2021 06 03.
Article in English | MEDLINE | ID: mdl-33295623

ABSTRACT

We have carried out a comparative study of the conformational impact of modifications to threonine residues of either α-O-Man or α-O-GalNAc in the context of a sequence from the mucin-like region of α-dystroglycan. Both such modifications can coexist in this domain of the glycoprotein. Solution NMR experiments and molecular dynamics calculations were employed. Comparing the results for an unmodified peptide Ac- PPTTTTKKP-NH2 sequence from α-dystroglycan, and glycoconjugates with either modification on the Ts, we find that the impact of the α-O-Man modification on the peptide scaffold is quite limited, while that of the α-O-GalNAc is more profound. The results for the α-O-GalNAc glycoconjugate are consistent with what has been seen earlier in other systems. Further examination of the NMR-based structure and the MD results suggest a more extensive network of hydrogen bond interactions within the α-O-GalNAc-threonine residue than has been previously appreciated, which influences the properties of the protein backbone. The conformational effects are relevant to the mechanical properties of α-dystroglycan.


Subject(s)
Dystroglycans/chemistry , Glycoproteins/chemistry , Dystroglycans/metabolism , Glycoproteins/metabolism , Molecular Conformation , Molecular Dynamics Simulation , Nuclear Magnetic Resonance, Biomolecular , Protein Processing, Post-Translational
4.
BMC Public Health ; 20(1): 19, 2020 Jan 07.
Article in English | MEDLINE | ID: mdl-31910846

ABSTRACT

BACKGROUND: Participation in organised sport and physical activity contributes to health-enhancing levels of leisure time physical activity. In Australia, 58% of children aged 0-14 years participated at least once a week in October 2015 - December 2017. To overcome the frequently cited cost barrier, sports voucher incentives have been widely implemented across Australia. METHOD: The financial value of jurisdictional vouchers and the National median financial value were used to calculate the proportion of total annual expenditure on children's participation in sport supported by sports vouchers. Participation rates using AusPlay data were estimated by age, sex and socio-economic index (SEIFA) at state and national level for children aged 0-14 years. RESULTS: Five States and Territories implemented sports vouchers from 2011 to 2018, with a median value of AU$150. Nationally, median annual expenditure for children's sport participation was AU$447 (IQR $194.2-936), with 27% reported expenditure supported by a sports voucher. The proportion of financial support from sports vouchers increased considerably with social disadvantage, rising to over 60% of total expenditure in the most disadvantaged populations. CONCLUSIONS: Socio-economic status was associated with sports-related expenditure and sports participation amongst children. Sport vouchers should target children in the most disadvantaged areas to promote participation in organised sport and physical activity.


Subject(s)
Exercise/psychology , Financial Support , Health Promotion/economics , Health Promotion/methods , Motivation , Sports/economics , Sports/psychology , Adolescent , Australia , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Social Class
5.
QJM ; 112(9): 663-667, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31147713

ABSTRACT

BACKGROUND: Infective endocarditis (IE) is a potentially life-threatening infection of the heart's endocardial surface. Despite advances in the diagnosis and management of IE, morbidity and mortality remain high. AIM: To characterize the demographics, bacteriology and outcomes of IE cases presenting to an Irish tertiary referral centre. DESIGN: Retrospective cohort study. METHODS: Patients were identified using Hospital Inpatient Enquiry and Clinical Microbiology inpatient consult data, from January 2005 to January 2014. Patients were diagnosed with IE using Modified Duke Criteria. Standard Bayesian statistics were employed for analysis and cases were compared to contemporary international registries. RESULTS: Two hundred and two patients were diagnosed with IE during this period. Mean age 54 years. Of these, 136 (67%) were native valve endocarditis (NVE), 50 (25%) were prosthetic valve endocarditis (PVE) and 22 (11%) were cardiovascular implantable electronic device-associated endocarditis. Culprit organism was identified in 176 (87.1%) cases and Staphylococcal species were the most common (57.5%). Fifty-nine per cent of NVE required surgery compared to 66% of PVE. Mean mortality rate was 17.3%, with NVE being the lowest (12.5%) and PVE the highest (32%). Increasing age was also associated with increased mortality. Fifty-three (26.2%) patients had embolic complications. CONCLUSIONS: This Irish cohort exhibited first-world demographic patterns comparable to those published in contemporary international literature. PVE required surgery more often and was associated with higher rates of mortality than NVE. Embolic complications were relatively common and represent important sequelae, especially in the intravenous drug user population. It is also pertinent to aggressively treat older cohorts as they were associated with increased mortality.


Subject(s)
Endocarditis/epidemiology , Endocarditis/mortality , Heart Valve Prosthesis/adverse effects , Prosthesis-Related Infections/epidemiology , Prosthesis-Related Infections/mortality , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Bacterial Infections/epidemiology , Bacterial Infections/mortality , Bayes Theorem , Female , Hospital Mortality , Humans , Ireland/epidemiology , Male , Middle Aged , Retrospective Studies , Substance Abuse, Intravenous/complications , Tertiary Care Centers , Young Adult
6.
BMC Public Health ; 17(1): 695, 2017 09 07.
Article in English | MEDLINE | ID: mdl-28882121

ABSTRACT

BACKGROUND: Few studies have reported energy balance-related behavior (EBRB) change for peer leaders delivering health promotion programs to younger students in secondary schools. Our study assessed the impact of the Students As LifeStyle Activists (SALSA) program on SALSA peer leaders' EBRBs, and their intentions regarding these behaviors. METHODS: We used a pre-post study design to assess changes in EBRBs and intentions of Year 10 secondary school students (15-16 year olds) who volunteered to be peer leaders to deliver the SALSA program to Year 8 students (13-14 year olds). This research is part of a larger study conducted during 2014 and 2015 in 23 secondary schools in Sydney, Australia. We used an online questionnaire before and after program participation to assess Year 10 peer leaders' fruit and vegetable intake, daily breakfast eating, sugar sweetened beverage (SSB) intake, moderate-to-vigorous physical activity (MVPA) participation and school-day recreational screen time behaviors and intentions regarding these EBRBs. Generalized estimating equations with a robust variance structure and exchangeable correlation structure were used to estimate the individual-level summary statistics and their 95% CIs, adjusted for clustering. We further assessed the effect of covariates on EBRB changes. RESULTS: There were significant increases in the proportion of Year 10 peer leaders (n = 415) who reported eating ≥2 serves fruit/day fruit from 54 to 63% (P < 0.01); eating ≥5 serves vegetables/day from 8 to 12% (P < 0.01); and drinking <1 cup/day of SSBs from 56 to 62% (P < 0.01). Change in ≥60 min MVPA participation/day depended on gender (P < 0.01): Boys increased 14% while girls decreased -2%. Changes in eating breakfast daily also depended on gender (P < 0.004): Boys increased 13% while girls decreased -0.4%. The change in peer leaders recreational screen time differed by socio-economic status (P < 0.05): above average communities decreased by -2.9% while below average communities increased 6.0%. Significant shifts were seen in peer leaders' intentions, except MVPA which remained stable. CONCLUSIONS: The SALSA program had a positive impact on peer leaders' EBRBs, with gender and socio-economic status moderating some outcomes. TRIAL REGISTRATION: ACTRN12617000712303 retrospectively registered.


Subject(s)
Diet/psychology , Energy Intake , Health Promotion/methods , Leadership , Peer Group , Students/psychology , Adolescent , Australia , Diet/statistics & numerical data , Female , Follow-Up Studies , Humans , Intention , Male , Program Evaluation , Schools , Students/statistics & numerical data , Surveys and Questionnaires
7.
Int J Cardiol Heart Vasc ; 16: 1-3, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28785604

ABSTRACT

BACKGROUND: TAVI is a percutaneous approach to aortic valve replacement in high surgical risk patients deemed inoperable. AIM: To evaluate the early and mid-term outcomes for an Irish TAVI cohort over a six-year period at St James's Hospital and Blackrock Clinic, Dublin, Ireland. RESULTS: In total 147 patients, 56% male with an average age of 82 underwent TAVI between December 2008 and December 2014. Thirty day, one year and two year survival was 90.5%, 83% and 71% respectively. Major vascular complications and renal failure were the biggest predictors of mortality at 30 days (p = 0.02). We observed a pacing rate of 13.5%, the majority in patients who had Medtronic Corevalve implants (p < 0.05). With increasing procedural experience there was a reduction in length of stay from 10 days to 7.5 days. CONCLUSION: This review, the first of its kind in Ireland showed favorable rates of 30 day and one year and two year survival post TAVI with procedural success and complication rates similar to international registry data.

8.
J Man Manip Ther ; 24(2): 74-9, 2016 May.
Article in English | MEDLINE | ID: mdl-27559276

ABSTRACT

BACKGROUND: Spinal fractures are typically considered a contraindication to mechanical diagnosis and therapy (MDT). OBJECTIVE AND IMPORTANCE: The purpose of this case study is to illustrate how MDT was used safely and effectively to treat lumbar pain in a patient with multiple lumbar transverse process fractures. CLINICAL PRESENTATION: The subject was a 24-year-old female with left L2-5 transverse process fractures, sustained 10 weeks prior in a pedestrian versus motor vehicle accident. INTERVENTION AND TECHNIQUE: After collaboration with her physiatrist, an MDT examination revealed a presentation consistent with the lumbar derangement syndrome. CONCLUSION: After three visits, utilizing patient generated forces with the extension principle of treatment, her pain, Oswestry disability index (ODI) score, and function all improved.

9.
J Am Chem Soc ; 138(24): 7636-48, 2016 06 22.
Article in English | MEDLINE | ID: mdl-27249581

ABSTRACT

Interactions between proteins and carbohydrates are ubiquitous in biology. Therefore, understanding the factors that determine their affinity and selectivity are correspondingly important. Herein, we have determined the relative strengths of intramolecular interactions between a series of monosaccharides and an aromatic ring close to the glycosylation site in an N-glycoprotein host. We employed the enhanced aromatic sequon, a structural motif found in the reverse turns of some N-glycoproteins, to facilitate face-to-face monosaccharide-aromatic interactions. A protein host was used because the dependence of the folding energetics on the identity of the monosaccharide can be accurately measured to assess the strength of the carbohydrate-aromatic interaction. Our data demonstrate that the carbohydrate-aromatic interaction strengths are moderately affected by changes in the stereochemistry and identity of the substituents on the pyranose rings of the sugars. Galactose seems to make the weakest and allose the strongest sugar-aromatic interactions, with glucose, N-acetylglucosamine (GlcNAc) and mannose in between. The NMR solution structures of several of the monosaccharide-containing N-glycoproteins were solved to further understand the origins of the similarities and differences between the monosaccharide-aromatic interaction energies. Peracetylation of the monosaccharides substantially increases the strength of the sugar-aromatic interaction in the context of our N-glycoprotein host. Finally, we discuss our results in light of recent literature regarding the contribution of electrostatics to CH-π interactions and speculate on what our observations imply about the absolute conservation of GlcNAc as the monosaccharide through which N-linked glycans are attached to glycoproteins in eukaryotes.


Subject(s)
Glycoproteins/chemistry , Hydrocarbons, Aromatic/chemistry , Monosaccharides/chemistry , Glycosylation , Magnetic Resonance Spectroscopy , Models, Molecular , Stereoisomerism , Thermodynamics
10.
J Magn Reson ; 265: 1-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26826977

ABSTRACT

A software package, MD2NOE, is presented which calculates Nuclear Overhauser Effect (NOE) build-up curves directly from molecular dynamics (MD) trajectories. It differs from traditional approaches in that it calculates correlation functions directly from the trajectory instead of extracting inverse sixth power distance terms as an intermediate step in calculating NOEs. This is particularly important for molecules that sample conformational states on a timescale similar to molecular reorientation. The package is tested on sucrose and results are shown to differ in small but significant ways from those calculated using an inverse sixth power assumption. Results are also compared to experiment and found to be in reasonable agreement despite an expected underestimation of water viscosity by the water model selected.


Subject(s)
Carbohydrate Conformation , Magnetic Resonance Spectroscopy/methods , Magnetic Resonance Spectroscopy/statistics & numerical data , Molecular Dynamics Simulation , Sucrose/chemistry , Algorithms , Computer Simulation , Models, Molecular , Software , Viscosity , Water/chemistry
11.
Toxicon ; 107(Pt A): 2-8, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26368006

ABSTRACT

The recent availability of multiple Clostridium botulinum genomic sequences has initiated a new genomics era that strengthens our understanding of the bacterial species that produce botulinum neurotoxins (BoNTs). Analysis of the genomes has reinforced the historical Group I-VI designations and provided evidence that the bont genes can be located within the chromosome, phage or plasmids. The sequences provide the opportunity to examine closely the variation among the toxin genes, the composition and organization of the toxin complex, the regions flanking the toxin complex and the location of the toxin within different bacterial strains. These comparisons provide evidence of horizontal gene transfer and site-specific insertion and recombination events that have contributed to the variation observed among the neurotoxins. Here, examples that have contributed to the variation observed in serotypes A-H strains are presented to illustrate the mechanisms that have contributed to their variation.


Subject(s)
Botulinum Toxins/genetics , Clostridium botulinum/genetics , Botulinum Toxins/metabolism , Botulinum Toxins, Type A/genetics , Clostridium botulinum/metabolism , Genes, Bacterial/genetics , Genetic Variation , Genome, Bacterial/genetics
12.
J Evol Biol ; 28(1): 155-68, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25403928

ABSTRACT

Thermal performance curves (TPCs) are continuous reaction norms that describe the relationship between organismal performance and temperature and are useful for understanding trade-offs involved in thermal adaptation. Although thermal trade-offs such as those between generalists and specialists or between hot- and cold-adapted phenotypes are known to be genetically variable and evolve during thermal adaptation, little is known of the genetic basis to TPCs - specifically, the loci involved and the directionality of their effects across different temperatures. To address this, we took a multivariate approach, mapping quantitative trait loci (QTL) for locomotor activity TPCs in the fly, Drosophila serrata, using a panel of 76 recombinant inbred lines. The distribution of additive genetic (co)variance in the mapping population was remarkably similar to the distribution of mutational (co)variance for these traits. We detected 11 TPC QTL in females and 4 in males. Multivariate QTL effects were closely aligned with the major axes genetic (co)variation between temperatures; most QTL effects corresponded to variation for either overall increases or decreases in activity with a smaller number indicating possible trade-offs between activity at high and low temperatures. QTL representing changes in curve shape such as the 'generalist-specialist' trade-off, thought key to thermal adaptation, were poorly represented in the data. We discuss these results in the light of genetic constraints on thermal adaptation.


Subject(s)
Adaptation, Physiological/genetics , Drosophila/genetics , Genetic Variation , Quantitative Trait Loci , Animals , Drosophila/physiology , Expressed Sequence Tags , Female , Male , Motor Activity , Multivariate Analysis , Mutation , Temperature
13.
J Chem Inf Model ; 54(10): 2744-50, 2014 Oct 27.
Article in English | MEDLINE | ID: mdl-25289680

ABSTRACT

We report a new classification method for pyranose ring conformations called Best-fit, Four-Membered Plane (BFMP), which describes pyranose ring conformations based on reference planes defined by four atoms. The method is able to characterize all asymmetrical and symmetrical shapes of a pyran ring, is readily automated, easy to interpret, and maps trivially to IUPAC definitions. It also provides a qualitative measurement of the distortion of the ring. Example applications include the analysis of data from crystal structures and molecular dynamics simulations.


Subject(s)
Algorithms , Heparitin Sulfate/chemistry , Mannose/chemistry , Pyrans/chemistry , Alkaloids/chemistry , Antineoplastic Agents/chemistry , Carbohydrate Conformation , Crystallography, X-Ray , Enzyme Inhibitors/chemistry , Humans , Mannosidases/antagonists & inhibitors , Mannosidases/chemistry , Molecular Dynamics Simulation
14.
Environ Pollut ; 184: 449-56, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24121420

ABSTRACT

Homologue and congener profiles of PCDD/Fs in eels, passive sampler and sediment extracts from the Burrishoole, a rural upland catchment on the western Irish seaboard were compared with potential PCDD sources. ΣPCDD/F levels in eels ranged from 2.9 to 25.9 pg g(-1) wet weight, which are elevated compared to other Irish locations. The OCDD congener dominated the pattern of ΣPCDD/Fs in all matrices from Burrishoole. Passive samplers were successfully deployed to identify for the first time the presence in the water column of PCDD/Fs and dimethoxylated octachlorodiphenyl ether (diMeOoctaCDE), impurities found in pentachlorophenol (PCP) production. Principal component analysis (PCA) identified similarities between PCDD/F profiles in technical PCP mixtures and environmental samples from the Burrishoole region. Results strongly suggest residual PCDD contamination associated with historic local use of a dioxin contaminated product in the catchment area, with pentachlorophenol a strong candidate.


Subject(s)
Benzofurans/analysis , Environmental Monitoring/methods , Polychlorinated Dibenzodioxins/analogs & derivatives , Polymers/analysis , Water Pollutants, Chemical/analysis , Animals , Benzofurans/metabolism , Eels/metabolism , Ireland , Pentachlorophenol , Polychlorinated Dibenzodioxins/analysis , Polychlorinated Dibenzodioxins/metabolism , Polymers/metabolism , Water Pollutants, Chemical/metabolism
15.
Heredity (Edinb) ; 111(5): 391-401, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23860232

ABSTRACT

Detailed studies of the genetics of speciation have focused on a few model systems, particularly Drosophila. The copepod Tigriopus californicus offers an alternative that differs from standard animal models in that it lacks heteromorphic chromosomes (instead, sex determination is polygenic) and has reduced opportunities for sexual conflict, because females mate only once. Quantitative trait loci (QTL) mapping was conducted on reciprocal F2 hybrids between two strongly differentiated populations, using a saturated linkage map spanning all 12 autosomes and the mitochondrion. By comparing sexes, a possible sex ratio distorter was found but no sex chromosomes. Although studies of standard models often find an excess of hybrid male sterility factors, we found no QTL for sterility and multiple QTL for hybrid viability (indicated by non-Mendelian adult ratios) and other characters. Viability problems were found to be stronger in males, but the usual explanations for weaker hybrid males (sex chromosomes, sensitivity of spermatogenesis, sexual selection) cannot fully account for these male viability problems. Instead, higher metabolic rates may amplify deleterious effects in males. Although many studies of standard speciation models find the strongest genetic incompatibilities to be nuclear-nuclear (specifically X chromosome-autosome), we found the strongest deleterious interaction in this system was mito-nuclear. Consistent with the snowball theory of incompatibility accumulation, we found that trigenic interactions in this highly divergent cross were substantially more frequent (>6×) than digenic interactions. This alternative system thus allows important comparisons to studies of the genetics of reproductive isolation in more standard model systems.


Subject(s)
Copepoda/genetics , Genes, Insect , Mitochondria/genetics , Animals , Chromosome Mapping , Epistasis, Genetic , Female , Genetic Loci , Larva/genetics , Male , Phenotype , Quantitative Trait Loci , Sex Characteristics , Sex Chromosomes , Sex Determination Processes , Sex Ratio , Zygote/physiology
16.
Ir Med J ; 106(2): 55-6, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23472389

ABSTRACT

Therapeutic hypothermia (TH) is a process of cooling a patient post ventricular tachycardia/ventricular fibrillation (VT/VF) cardiac arrest to 32-34 degrees C for 24 hours. This improves neurological outcome and is part of current guidelines. Hypothermia prolongs QT interval, which can precipitate torsades de pointes (TdP). We performed a retrospective review of all patients who received TH in our hospital over a period of 2 years to assess the effect of TH on the corrected OT interval (QTc) and any possible pro-arrhythmia. A total of 13 patients received TH. QTc prolonged in all patients with an average of 80.3 + 57.2 ms., and up to 109.8 + 80.4 ms in patients who received Amiodarone concurrently. No TdP was seen in any patient. We conclude that TH is safe, though careful monitoring of the OTc interval is advisable especially with concurrent use of QT prolonging drugs.


Subject(s)
Heart Arrest/physiopathology , Heart Arrest/therapy , Hypothermia, Induced/adverse effects , Amiodarone/therapeutic use , Anti-Arrhythmia Agents/therapeutic use , Electrocardiography , Female , Heart Arrest/complications , Humans , Male , Middle Aged , Retrospective Studies , Tachycardia, Ventricular/complications , Time Factors , Ventricular Fibrillation/complications
17.
Haemophilia ; 18(2): 291-9, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21787373

ABSTRACT

To assess whether a genetic relationship exists between the viruses infecting HIV-positive patients with haemophilia and those infecting plasma donors, we determined the vif sequences in 169 individuals, including 20 haemophilia patients, 3 plasma donors, and 146 local controls. Twenty haemophilia patients were diagnosed with HIV-1 at 1-2 years after exposure to factor IX (FIX) manufactured in Korea, beginning in 1989-1990. Plasma samples from donors O and P were used to manufacture clotting factors including FIX used to treat the 20 haemophiliacs. The vif gene from frozen stored serum samples obtained 1-3 years after diagnosis was amplified by RT-PCR, and subjected to direct sequencing. Phylogenetic analysis revealed that vif sequences from 128 of the samples (including haemophilia patients and donors) belonged to the Korean subclade of HIV-1 subtype B (KSB). Sequences from 41 other participants were identified as subtype B, but outside the Korean subclade. Sequences of the vif gene from donors O and P plus the 20 individuals with haemophilia comprised two subclusters within KSB. In addition, signature pattern analysis disclosed the presence of conserved nucleotides at two positions in donors and haemophiliacs only. Together with information on KSB, dates of plasma donations and seroconversion of haemophilia patients, our results suggest that the haemophiliacs examined here became infected by viruses in the domestic clotting factor used for treatment.


Subject(s)
HIV Infections/virology , HIV-1/genetics , Hemophilia A/virology , Phylogeny , vif Gene Products, Human Immunodeficiency Virus/genetics , Blood Donors , HIV Infections/transmission , HIV-1/classification , Humans , Korea , Male , Reverse Transcriptase Polymerase Chain Reaction , Sequence Alignment
18.
Article in English | MEDLINE | ID: mdl-22029685

ABSTRACT

A rapid and sensitive LC-MS/MS method for the identification, quantification and confirmation of six primary aromatic amines (PAAs) was developed and validated to ISO 17025:2005. From a literature survey, 57 frequently used PAA compounds were identified and subsequently reduced to six - aniline, 4,4'-MDA, 3,3'-DMB, 2,4-TDA, 2,6-TDA and o-T - based on results from migration studies on a range of utensils. Low LOQs of between 0.075 and 0.496 µg l(-1) were determined for the six analytes, thereby quantifying well below the legal limit of 10 µg kg(-1) total PAAs. Furthermore, low measurement uncertainties were calculated for the analytical method, in the range of 3.15-3.20%. Mean recoveries were between 98% and 102% and spanned over ±12% at 95% CI. Following the analysis of 84 black polyamide kitchen utensils, the migration of PAAs detected was significant and is therefore of concern. The six analytes identified, quantified and confirmed in this survey could be utilised as possible markers for the identification of PAA migration, thereby improving the time and cost-efficiency of food control laboratories.


Subject(s)
Amines/chemistry , Cooking/instrumentation , Nylons/chemistry , Chromatography, Liquid , Limit of Detection , Reference Standards , Tandem Mass Spectrometry
19.
Wiley Interdiscip Rev Comput Mol Sci ; 2(4): 652-697, 2012 Jul.
Article in English | MEDLINE | ID: mdl-25530813

ABSTRACT

Carbohydrates present a special set of challenges to the generation of force fields. First, the tertiary structures of monosaccharides are complex merely by virtue of their exceptionally high number of chiral centers. In addition, their electronic characteristics lead to molecular geometries and electrostatic landscapes that can be challenging to predict and model. The monosaccharide units can also interconnect in many ways, resulting in a large number of possible oligosaccharides and polysaccharides, both linear and branched. These larger structures contain a number of rotatable bonds, meaning they potentially sample an enormous conformational space. This article briefly reviews the history of carbohydrate force fields, examining and comparing their challenges, forms, philosophies, and development strategies. Then it presents a survey of recent uses of these force fields, noting trends, strengths, deficiencies, and possible directions for future expansion.

20.
Anal Chim Acta ; 700(1-2): 26-33, 2011 Aug 26.
Article in English | MEDLINE | ID: mdl-21742113

ABSTRACT

A confirmatory multi-residue method has been developed to allow for the detection, confirmation and quantification of eleven coccidiostats in animal feed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The method can be used to determine halofuginone, robenidine, nicarbazin, diclazuril, decoquinate, semduramicin, lasalocid, monensin, salinomycin, narasin, maduramicin at levels relating to unavoidable carry over as stated in Regulation 2009/8/EC. Feed samples are extracted with water and acetonitrile with the addition of anhydrous magnesium sulphate and sodium chloride. The extract then undergoes a freezing out step before being diluted and injected onto the LC-MS/MS system. The LC-MS/MS system is run in MRM mode with both positive and negative electrospray ionisation and can confirm all eleven analytes in a run time of 19 min. The sensitivity of the method allows quantification and confirmation for all coccidiostats at a 0.5% carry over level. The method was validated over three days in accordance with of European legislation; Commission Decision 2002/657/EC. Validation criteria of accuracy, precision, decision limit (CCα), and detection capability (CCß) along with measurement uncertainty are calculated for all analytes. The method was then successfully used to analyse a number of feed samples that contained various coccidiostat substances.


Subject(s)
Animal Feed/analysis , Chromatography, High Pressure Liquid/methods , Coccidiostats/analysis , Tandem Mass Spectrometry/methods , Acetonitriles/chemistry , Animals , Magnesium Sulfate/chemistry , Sodium Chloride/chemistry , Water/chemistry
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