1
|
Weishaar RE, Burrows SD, Kobylarz DC, Quade MM, Evans DB. Multiple molecular forms of cyclic nucleotide phosphodiesterase in cardiac and smooth muscle and in platelets. Isolation, characterization, and effects of various reference phosphodiesterase inhibitors and cardiotonic agents. Biochem Pharmacol 1986; 35:787-800. [PMID: 3006691 DOI: 10.1016/0006-2952(86)90247-9] [Citation(s) in RCA: 184] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Multiple molecular forms of cyclic nucleotide phosphodiesterase have been identified previously in several tissues and cell types using a variety of different isolation methods. In the present study, the different molecular forms of phosphodiesterase (PDE) were isolated from cardiac muscle (guinea pig left ventricle), vascular smooth muscle (bovine coronary arteries) and human platelets using the same isolation procedure in each instance. These enzymes were then characterized kinetically, and the effects of various reference PDE inhibitors and cardiotonic agents on each form were examined. A low Km, low Vmax form of phosphodiesterase (PDE I) was found in all three tissue/cell types. PDE I activity was stimulated by calmodulin in cardiac and smooth muscle, but not in platelets. In smooth muscle and platelets, PDE I preferentially hydrolyzed cyclic GMP, whereas cardiac muscle PDE I hydrolyzed cyclic AMP and cyclic GMP equally. A high Km, high Vmax form of phosphodiesterase (PDE II) was found in cardiac muscle and platelets, but not in smooth muscle. PDE II activity was not stimulated by calmodulin and there was no substrate specificity. A low Km, low Vmax cyclic AMP-specific form of phosphodiesterase (PDE III) was found in all three tissue/cell types. The activity of PDE III was not stimulated by calmodulin. The reference inhibitors theophylline and papaverine exerted non-specific inhibitory effects on all forms of phosphodiesterase. Other reference inhibitors (M & B 22,948 and dipyridamole) and several cardiotonic agents (AR-L 57, CI-914, CI-930, amrinone, and MDL 17,043) exerted selective inhibitory effects on only one molecular form of phosphodiesterase. The degree of selectivity was often dependent upon the tissue or cell from which the molecular form of phosphodiesterase was isolated. These studies demonstrate that there is heterogeneity regarding the number of phosphodiesterases present in various tissue/cell types, as well as their substrate specificity and their ability to be stimulated by calmodulin, and these different molecular forms of phosphodiesterase can be selectively inhibited by different pharmacological agents. The possibility exists that such selective inhibitors may produce discrete changes in cyclic AMP or cyclic GMP levels, and that these changes may be produced in specific tissues and/or cells.
Collapse
|
|
39 |
184 |
2
|
Girgis A, Boyes A, Sanson-Fisher RW, Burrows S. Perceived needs of women diagnosed with breast cancer: rural versus urban location. Aust N Z J Public Health 2000; 24:166-73. [PMID: 10790936 DOI: 10.1111/j.1467-842x.2000.tb00137.x] [Citation(s) in RCA: 166] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
OBJECTIVE To assess the prevalence and predictors of perceived unmet needs among women diagnosed with breast cancer, with a particular focus on the impact of location (rural/urban). METHOD A random sample of women in NSW diagnosed with breast cancer was surveyed during 1995-96. The Breast Cancer Patients' Needs Questionnaire (BR-CPNQ) explores patients' perceived needs across five domains: psychological, health information, physical/daily living, patient care/support and interpersonal communication. Items assessing breast cancer specific needs and access to services and resources were included. Of 235 eligible rural women, 134 (57%) consented to participate and 129 (55%) returned completed surveys. Of 196 eligible urban women, 102 (52%) consented to participate and 100 (51%) returned completed surveys. RESULTS For 12 of the 52 items, at least one-third of the sample reported ever having a moderate/high need for help. Of the 15 highest moderate or high unmet needs, 10 related to health information and three to psychological needs. There were few differences in the prevalence of needs reported by rural and urban women. Only in the physical/daily living domain were rural women more likely than urban women to report some need for help (OR = 2.59, 95% CI 1.21-5.52). CONCLUSIONS Unmet needs, particularly in the information and psycho-social domains, are reported by both rural and urban women with breast cancer, with sub-groups experiencing different types of needs. IMPLICATIONS There is a need to develop and trial targeted and innovative strategies to meet the health information and psychological needs of women with breast cancer, and the physical/daily living needs of rural women diagnosed with breast cancer.
Collapse
|
Comparative Study |
25 |
166 |
3
|
Hajek P, West R, Foulds J, Nilsson F, Burrows S, Meadow A. Randomized comparative trial of nicotine polacrilex, a transdermal patch, nasal spray, and an inhaler. ARCHIVES OF INTERNAL MEDICINE 1999; 159:2033-8. [PMID: 10510989 DOI: 10.1001/archinte.159.17.2033] [Citation(s) in RCA: 156] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND There are several nicotine replacement products on the market, and physicians are likely to be asked with increasing frequency about which of these products their patients should use. OBJECTIVE To provide a basis for rational advice by comparing nicotine polacrilex (gum), a transdermal patch, nasal spray, and an inhaler. DESIGN Randomized trial with assessments at the quit date and 1, 4, and 12 weeks later. SETTING Hospital smokers' clinic. PATIENTS Male and female community volunteers (N = 504) smoking 10 or more cigarettes per day and seeking help to stop smoking. INTERVENTIONS Patients were given brief advice, and purchased their nicotine replacement treatment at approximately half the regular retail price. MAIN OUTCOME MEASURES Nicotine replacement treatment use, ratings of withdrawal symptoms, ratings of product characteristics and helpfulness, and biochemically validated continuous lapse-free abstinence. RESULTS The products did not differ in their effects on withdrawal discomfort, urges to smoke, or rates of abstinence. The continuous validated 12-week abstinence rates were 20%, 21%, 24%, and 24% in the gum, patch, spray, and inhaler groups, respectively. Compliance with recommended nicotine replacement treatment use was high for the patch, low for gum, and very low for the spray and the inhaler. The spray was underused because of adverse effects more often than the other products. In the subjects using the spray, the level of use among abstainers at week 1 predicted outcome at week 12. The inhaler was rated as more embarrassing to use than the other products, but provided at least as much nicotine as the gum. CONCLUSION When asked about nicotine replacement treatment products available, physicians should note that, despite low compliance with the recommended dose of the spray and inhaler and differences in product ratings, overall, there are no notable differences between the products in their effects on withdrawal discomfort, perceived helpfulness, or general efficacy.
Collapse
|
Clinical Trial |
26 |
156 |
4
|
Burrows SD, Doyle ML, Murphy KP, Franklin SG, White JR, Brooks I, McNulty DE, Scott MO, Knutson JR, Porter D. Determination of the monomer-dimer equilibrium of interleukin-8 reveals it is a monomer at physiological concentrations. Biochemistry 1994; 33:12741-5. [PMID: 7947677 DOI: 10.1021/bi00209a002] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Interleukin-8 has been shown by X-ray crystallography and NMR to be a homodimer, suggesting that this is the form which binds to its receptor. Here we measure, for the first time, the monomer-dimer equilibrium of interleukin-8 using analytical ultracentrifugation and titration microcalorimetry and find that it dissociates readily to monomers with an equilibrium dissociation constant of 18 +/- 6 microM at 37 degrees C. The present findings suggest that the monomer is the form which binds to the receptor. Comparison of experimental and structure-based calculated thermodynamics of interleukin-8 dimerization argues for limited subunit conformational changes upon dissociation to monomer.
Collapse
|
Comparative Study |
31 |
124 |
5
|
O'Brien S, Rauert C, Ribeiro F, Okoffo ED, Burrows SD, O'Brien JW, Wang X, Wright SL, Thomas KV. There's something in the air: A review of sources, prevalence and behaviour of microplastics in the atmosphere. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 874:162193. [PMID: 36828069 DOI: 10.1016/j.scitotenv.2023.162193] [Citation(s) in RCA: 69] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
Literature regarding microplastics in the atmosphere has advanced in recent years. However, studies have been undertaken in isolation with minimal collaboration and exploration of the relationships between air, deposition and dust. This review collates concentrations (particle count and mass-based), shape, size and polymetric characteristics for microplastics in ambient air (m3), deposition (m2/day), dust (microplastics/g) and snow (microplastics/L) from 124 peer-reviewed articles to provide a holistic overview and analysis of our current knowledge. In summary, ambient air featured concentrations between <1 to >1000 microplastics/m3 (outdoor) and <1 microplastic/m3 to 1583 ± 1181 (mean) microplastics/m3 (indoor), consisting of polyethylene terephthalate, polyethylene, polypropylene. No difference (p > 0.05) was observed between indoor and outdoor concentrations or the minimum size of microplastics (p > 0.5). Maximum microplastic sizes were larger indoors (p < 0.05). Deposition concentrations ranged between 0.5 and 1357 microplastics/m2/day (outdoor) and 475 to 19,600 microplastics/m2/day (indoor), including polyethylene, polystyrene, polypropylene, polyethylene terephthalate. Concentrations varied between indoor and outdoor deposition (p < 0.05), being more abundant indoors, potentially closer to sources/sinks. No difference was observed between the minimum or maximum reported microplastic sizes within indoor and outdoor deposition (p > 0.05). Road dust concentrations varied between 2 ± 2 and 477 microplastics/g (mean), consisting of polyvinyl chloride, polyethylene, polypropylene. Mean outdoor dust concentrations ranged from <1 microplastic/g (remote desert) to between 18 and 225 microplastics/g, comprised of polyethylene terephthalate, polyamide, polypropylene. Snow concentrations varied between 0.1 and 30,000 microplastics/L, containing polyethylene, polyamide, polypropylene. Concentrations within indoor dust varied between 10 and 67,000 microplastics/g, including polyethylene terephthalate, polyethylene, polypropylene. No difference was observed between indoor and outdoor concentrations (microplastics/g) or maximum size (p > 0.05). The minimum size of microplastics were smaller within outdoor dust (p > 0.05). Although comparability is hindered by differing sampling methods, analytical techniques, polymers investigated, spectral libraries and inconsistent terminology, this review provides a synopsis of knowledge to date regarding atmospheric microplastics.
Collapse
|
Review |
2 |
69 |
6
|
Okoffo ED, Donner E, McGrath SP, Tscharke BJ, O'Brien JW, O'Brien S, Ribeiro F, Burrows SD, Toapanta T, Rauert C, Samanipour S, Mueller JF, Thomas KV. Plastics in biosolids from 1950 to 2016: A function of global plastic production and consumption. WATER RESEARCH 2021; 201:117367. [PMID: 34182349 DOI: 10.1016/j.watres.2021.117367] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/22/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
Plastics are ubiquitous contaminants that leak into the environment from multiple pathways including the use of treated sewage sludge (biosolids). Seven common plastics (polymers) were quantified in the solid fraction of archived biosolids samples from Australia and the United Kingdom from between 1950 and 2016. Six plastics were detected, with increasing concentrations observed over time for each plastic. Biosolids plastic concentrations correlated with plastic production estimates, implying a potential link between plastics production, consumption and leakage into the environment. Prior to the 1990s, the leakage of plastics into biosolids was limited except for polystyrene. Increased leakage was observed from the 1990s onwards; potentially driven by increased consumption of polyethylene, polyethylene terephthalate and polyvinyl chloride. We show that looking back in time along specific plastic pollution pathways may help unravel the potential sources of plastics leakage into the environment and provide quantitative evidence to support the development of source control interventions or regulations.
Collapse
|
|
4 |
66 |
7
|
Okoffo ED, Tscharke BJ, O'Brien JW, O'Brien S, Ribeiro F, Burrows SD, Choi PM, Wang X, Mueller JF, Thomas KV. Release of Plastics to Australian Land from Biosolids End-Use. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:15132-15141. [PMID: 33200922 DOI: 10.1021/acs.est.0c05867] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Plastics are contaminants of emerging concern that can enter the environment from multiple sources, including via land application of treated sewage sludge (biosolids). Biosolids samples collected from 82 wastewater treatment plants (WWTPs) across Australia and covering 34% of the population during census week in 2016 were quantitatively analyzed to estimate the release of seven common plastics. Quantitative analysis was performed by pressurized liquid extraction followed by double-shot microfurnace pyrolysis coupled to gas chromatography mass spectrometry. Ninety nine percent of the samples contained plastics (Σ6plastics) at concentrations of between 0.4 and 23.5 mg/g dry weight (median; 10.4 mg/g dry weight), while polycarbonate was not detected in any sample. Per-capita mass loads of plastics (Σ6plastics) released were between 8 and 877 g/person/year across all investigated WWTPs. Polyethylene was the predominant plastic detected, contributing to 69% of Σ6plastics. Based on the concentrations measured, it was projected that around 4700 metric tons (Mt) of plastics are released into the Australian environment through biosolids end-use each year, equating to approximately 200 g/person/year, which represents 0.13% of total plastics use in Australia. Of this, 3700 Mt of plastics are released to agricultural lands and 140 Mt to landscape topsoil. Our results provide a first quantitative per-capita mass loads and emission estimate of plastic types through biosolids end-use.
Collapse
|
|
5 |
55 |
8
|
Moss DJ, Schmidt C, Elliott S, Suhrbier A, Burrows S, Khanna R. Strategies involved in developing an effective vaccine for EBV-associated diseases. Adv Cancer Res 1996; 69:213-45. [PMID: 8791683 DOI: 10.1016/s0065-230x(08)60864-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
|
Review |
29 |
46 |
9
|
O'Brien S, Okoffo ED, Rauert C, O'Brien JW, Ribeiro F, Burrows SD, Toapanta T, Wang X, Thomas KV. Quantification of selected microplastics in Australian urban road dust. JOURNAL OF HAZARDOUS MATERIALS 2021; 416:125811. [PMID: 33892382 DOI: 10.1016/j.jhazmat.2021.125811] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 03/29/2021] [Accepted: 04/01/2021] [Indexed: 06/12/2023]
Abstract
Microplastics (1 - 5000 µm) are pervasive in every compartment of our environment. However, little is understood regarding the concentration and size distribution of microplastics in road dust, and how they change in relation to human activity. Within road dust, microplastics move through the environment via atmospheric transportation and stormwater run-off into waterways. Human exposure pathways to road dust include dermal contact, inhalation and ingestion. In this study, road dust along an urban to rural transect within South-East Queensland, Australia was analysed using Accelerated Solvent Extraction followed by pyrolysis Gas Chromatography-Mass Spectrometry (Pyr-GC/MS). Polypropylene, polystyrene, polyethylene terephthalate, polyvinyl chloride, poly (methyl methacrylate) and polyethylene were quantified. Microplastic concentrations ranged from ~0.5 mg/g (rural site) to 6 mg/g (Brisbane city), consisting primarily of polyvinyl chloride (29%) and polyethylene terephthalate (29%). Size fractionation (< 250 µm, 250-500 µm, 500-1000 µm, 1000-2000 µm and 2000-5000 µm) established that the < 250 µm size fraction contained the majority of microplastics by mass (mg/g). Microplastic concentrations in road dust demonstrated a significant relationship with the volume of vehicles (r2 = 0.63), suggesting traffic, as a proxy for human movement, is associated with increased microplastic concentrations in the built environment.
Collapse
|
|
4 |
36 |
10
|
Apolloni A, Moss D, Stumm R, Burrows S, Suhrbier A, Misko I, Schmidt C, Sculley T. Sequence variation of cytotoxic T cell epitopes in different isolates of Epstein-Barr virus. Eur J Immunol 1992; 22:183-9. [PMID: 1370413 DOI: 10.1002/eji.1830220127] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Previous results have identified two distinct cytotoxic T lymphocyte (CTL) epitopes encoded by Epstein-Barr virus (EBV), TETA (ORF BLRF3/BERF1 residues 329-353) and EENL (ORF BERF3/BERF4 residues 290-309). Measurement of the specificities of CTL clones (TETA-specific clone 13 and EENL-specific clone 7) directed against these epitopes indicated that the EENL epitope is conserved in all strains of EBV tested while the TETA epitope varied between individual virus strains. Sequencing of the DNA regions encoding these two CTL epitopes in different EBV isolates confirmed these interpretations and demonstrated that different TETA epitope sequences were encoded by B-type EBV strains and by the B95-8 isolate of EBV compared to the other A-type EBV strains. Titration of synthetic variants of the TETA epitope revealed that the epitope encoded by B95-8 was 15-fold less efficient as a T cell epitope than the sequence encoded by other A-type viral strains while the TETA variant encoded by the B-type strains displayed essentially no activity as a T cell epitope.
Collapse
|
|
33 |
34 |
11
|
Burrows S, Auger N, Roy M, Alix C. Socio-economic inequalities in suicide attempts and suicide mortality in Québec, Canada, 1990-2005. Public Health 2010; 124:78-85. [PMID: 20181370 DOI: 10.1016/j.puhe.2010.01.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Revised: 11/30/2009] [Accepted: 01/13/2010] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Little research has evaluated changes in the association between area deprivation and suicidal behaviour over time. This study investigated patterns in suicide attempts and suicide mortality according to material deprivation in the province of Québec, Canada between 1990 and 2005. STUDY DESIGN Ecological analysis. METHODS Data on suicide attempts were extracted from the hospital discharge summary database (n=47,516) and data on suicides were extracted from the Québec death file (n=20,851). Gender- and age-specific (10-24, 25-44, 45-64 and > or = 65 years) suicide attempt and mortality rates were calculated for four time periods (1990-1993, 1994-1997, 1998-2001 and 2002-2005) for the entire Québec population aged 10 years and older residing in 162 communities ranked by decile of material deprivation. Absolute and relative measures of inequality were calculated to summarize differences between the most and least materially deprived areas. Commonly used methods of suicidal behaviour were examined. RESULTS Differentials in suicide attempt hospitalization between the most and least deprived areas were present for all age groups, and these decreased slightly among males and increased among females over time. Inequalities in suicide attempts were greatest among young adults (age 25-44 years) for both genders, and were smallest among the elderly (> or = 65 years). For suicide mortality, differentials increased among females but not males; these differentials were greatest among males and 25-44 year olds, and smallest among the elderly. Differentials in commonly used methods were evident for poisoning hospitalizations in both genders and for hanging deaths among males. CONCLUSIONS In Québec, differences in suicide attempts and mortality between the most and least materially deprived areas persisted or even increased over time. Inequalities were more pronounced for suicide attempts than for suicide mortality, and were greatest among adults of working age. Strategies to reduce socio-economic differences in suicidal behaviour may be important.
Collapse
|
Research Support, Non-U.S. Gov't |
15 |
29 |
12
|
Burrows S, Vaez M, Butchart A, Laflamme L. The share of suicide in injury deaths in the South African context: sociodemographic distribution. Public Health 2003; 117:3-10. [PMID: 12802898 DOI: 10.1016/s0033-3506(02)00019-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This study describes the sociodemographic distribution of suicide deaths compared with other injury deaths in South Africa. Cross-sectional data for 26,354 cases were extracted from an injury surveillance database. These included all manners of injury death from 10 mortuaries for 1999-2000 (approximately 18-20% coverage of all injury deaths per year). They were used to examine the distribution of suicide across different sex, race and age groupings, and the relative involvement of alcohol across manners of death. The share of suicide as a cause of death was comparable for males and females, but varied considerably across races and age groups. It was twice as high for Whites as for Asians, and four times as high as for Coloureds and Blacks. For all races except Whites, suicides were concentrated in the younger age groups. Only among Whites was the proportion of alcohol-positive suicides higher or comparable with that for other manners of death. While homicides and unitentional injury deaths outnumbered suicides overall, the relative importance of suicide in some social groups is reason for concern. South Africa is a country undergoing profound transformations, and differences in the distribution of suicide across sociodemographic groups deserve attention.
Collapse
|
Comparative Study |
22 |
25 |
13
|
|
|
16 |
25 |
14
|
Abstract
Clients attending a smokers clinic were randomly allocated to two groups to assess the effects of glucose tablets in reducing craving for cigarettes. Smokers who had already been abstinent for 1 week were eligible to take part in the study. All subjects completed rating relating to urge to smoke and craving. Then subjects in one group were given packets of dextrose tablets and those in the other group were given packets of tablets containing sorbitol (a low calorie sweetener). Ratings of urges to smoke and craving were taken after 1 week, during which time the subjects had been asked to chew their tablets ad lib. Eight out of ten smokers in each group maintained abstinence. The remaining two smokers either did not abstain or did not turn up for the second measurement session. There was a significant reduction in ratings of urges to smoke and craving in the glucose group compared with the sorbitol group. These results support a theory postulating a link between glucoregulation and cigarette craving. If the results are replicated and it is shown that the reduction in craving translates into improved abstinence rates, oral glucose could be of assistance to smokers wishing to give up.
Collapse
|
Clinical Trial |
35 |
24 |
15
|
|
|
54 |
24 |
16
|
Burrows SD, Frustaci S, Thomas KV, Galloway T. Expanding exploration of dynamic microplastic surface characteristics and interactions. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2020.115993] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
|
5 |
23 |
17
|
Toapanta T, Okoffo ED, Ede S, O'Brien S, Burrows SD, Ribeiro F, Gallen M, Colwell J, Whittaker AK, Kaserzon S, Thomas KV. Influence of surface oxidation on the quantification of polypropylene microplastics by pyrolysis gas chromatography mass spectrometry. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 796:148835. [PMID: 34280630 DOI: 10.1016/j.scitotenv.2021.148835] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/29/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
The influence of photo-oxidation on the quantification of isotactic polypropylene by Pyrolysis Gas Chromatography/Mass Spectrometry (Pyr-GC/MS) was assessed. Beads (oval shape, ~5 mm) and fragments (irregular shaped, 250-50 μm and 500-1000 μm) were subjected to relatively harsh simulated accelerated weathering conditions (using a filtered xenon-arc reproducing sunlight's full spectrum) for up to 37 and 80 days, respectively. Samples collected (n = 10 replicates for each treatment) at increasing number of weathering days were analysed by Fourier-transform infrared spectroscopy with Attenuated Total Reflection (FTIR-ATR), scanning electron microscopy, and differential scanning calorimetry in order to assess the extent and the rate of degradation. The rate of surface oxidation occurred faster for fragments compared to beads, probably due to their higher surface area. Quantification of the polypropylene trimer (2,4-dimethyl-1-heptene) via double shot Pyr-GC/MS, showed that the signal of the trimer relative to the mass of polypropylene was reduced through weathering with a degradation rate of 1:3 faster for fragments over beads. Signal reduction and carbonyl index were correlated to show that polypropylene with a carbonyl index of ≥13 has a significantly reduced 2,4-dimethyl-1-heptene signal when compared to virgin material. Consequently, the quantification of polypropylene subjected to weathering under harsh conditions may be underestimated by 42% (fragments, carbonyl index: 18) to 49% (beads, carbonyl index: 30) when quantified by Pyr-GC/MS and using virgin polypropylene calibration standards. Pyrolysis at a lower temperature (350 °C) identified six degradation specific markers (oxidation products) that increased in concentration with weathering. Further comparisons between virgin and weathered microplastics may need to be considered to avoid underestimation of microplastic concentrations in future studies.
Collapse
|
|
4 |
20 |
18
|
Okoffo ED, O'Brien S, Ribeiro F, Burrows SD, Toapanta T, Rauert C, O'Brien JW, Tscharke BJ, Wang X, Thomas KV. Plastic particles in soil: state of the knowledge on sources, occurrence and distribution, analytical methods and ecological impacts. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2021; 23:240-274. [PMID: 33514987 DOI: 10.1039/d0em00312c] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Increased production and use of plastics has resulted in growth in the amount of plastic debris accumulating in the environment, potentially fragmenting into smaller pieces. Fragments <5 mm are typically defined as microplastics, while fragments <0.1 μm are defined as nanoplastics. Over the past decade, an increasing number of studies have reported the occurrence and potential hazards of plastic particles in the aquatic environment. However, less is understood about plastic particles in the terrestrial environment and specifically how much plastic accumulates in soils, the possible sources, potential ecological impacts, interaction of plastic particles with the soil environment, and appropriate extraction and analytical techniques for assessing the above. In this review, a comprehensive overview and a critical perspective on the current state of knowledge on plastic pollution in the soil environment is provided: detailing known sources, occurrence and distribution, analytical techniques used for identification and quantification and the ecological impacts of particles on soil. In addition, knowledge gaps are identified along with suggestions for future research.
Collapse
|
Review |
4 |
19 |
19
|
Campbell E, Walsh RA, Sanson-Fisher R, Burrows S, Stojanovski E. A group randomised trial of two methods for disseminating a smoking cessation programme to public antenatal clinics: effects on patient outcomes. Tob Control 2006; 15:97-102. [PMID: 16565456 PMCID: PMC2563553 DOI: 10.1136/tc.2004.011049] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2004] [Accepted: 10/31/2005] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To assess the differential effectiveness of two methods of disseminating a smoking cessation programme to public hospital antenatal clinics. DESIGN Group randomised trial. SETTING 22 antenatal clinics in New South Wales, Australia. INTERVENTION Clinics were allocated to a simple dissemination (SD) condition (11 clinics) which received a mail-out of programme resources or to an intensive dissemination (ID) condition (11 clinics) which included the mail-out plus feedback, training, and ongoing support with midwife facilitator. MAIN OUTCOME MEASURES Independent cross sectional surveys of women on a second or subsequent visit undertaken pre-dissemination and 18 months after dissemination. Outcomes were: (1) levels of smoking status assessment by clinic staff; (2) proportion of women identifying as having been smokers at their first visit who reported receiving cessation advice; (3) proportion of these women who had quit (self report and expired air carbon monoxide (CO)); and (4) smoking prevalence among all women (self report and CO). SUBJECTS 5849 women pre-dissemination (2374 SD, 3475 ID) and weighted sample of 5145 women post-dissemination (2302 SD, 2843 ID). RESULTS There were no significant differences between the groups on change on any outcome. Change in either group was minimal. In the post-dissemination survey, the cessation proportions were 6.4% (SD) and 10.5% (ID). CONCLUSIONS Relatively modest strategies for encouraging incorporation of smoking cessation activities into antenatal care were not effective in the long term. Alternative strategies should be implemented and evaluated. The findings reinforce the importance of a whole population approach to tobacco control.
Collapse
|
Multicenter Study |
19 |
18 |
20
|
See VHL, Mas E, Burrows S, O'Callaghan NJ, Fenech M, Prescott SL, Beilin LJ, Huang RC, Mori TA. Prenatal omega-3 fatty acid supplementation does not affect offspring telomere length and F2-isoprostanes at 12 years: A double blind, randomized controlled trial. Prostaglandins Leukot Essent Fatty Acids 2016; 112:50-5. [PMID: 27637341 DOI: 10.1016/j.plefa.2016.08.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 08/16/2016] [Indexed: 01/02/2023]
Abstract
BACKGROUND Oxidative stress and nutritional deficiency may influence the excessive shortening of the telomeric ends of chromosomes. It is known that stress exposure in intrauterine life can produce variations in telomere length (TL), thereby potentially setting up a long-term trajectory for disease susceptibility. OBJECTIVE To assess the effect of omega-3 long chain polyunsaturated fatty acid (n-3 LCPUFA) supplementation during pregnancy on telomere length and oxidative stress in offspring at birth and 12 years of age (12y). DESIGN In a double-blind, placebo-controlled, parallel-group study, 98 pregnant atopic women were randomised to 4g/day of n-3 LCPUFA or control (olive oil [OO]), from 20 weeks gestation until delivery. Telomere length as a marker of cell senescence and plasma and urinary F2-isoprostanes as a marker of oxidative stress were measured in the offspring at birth and 12y. RESULTS Maternal n-3 LCPUFA supplementation did not influence offspring telomere length at birth or at 12y with no changes over time. Telomere length was not associated with F2-isoprostanes or erythrocyte total n-3 fatty acids. Supplementation significantly reduced cord plasma F2-isoprostanes (P<0.001), with a difference in the change over time between groups (P=0.05). However, the differences were no longer apparent at 12y. Between-group differences for urinary F2-isoprostanes at birth and at 12y were non-significant with no changes over time. CONCLUSIONS This study does not support the hypothesis that n-3 LCPUFA during pregnancy provides sustained effects on postnatal oxidative stress and telomere length as observed in the offspring.
Collapse
|
Randomized Controlled Trial |
9 |
15 |
21
|
|
|
51 |
14 |
22
|
Burrows S, Feldman W, McBride F. Serum gamma-glutamyl transpeptidase. Evaluation in screening of hospitalized patients. Am J Clin Pathol 1975; 64:311-4. [PMID: 240269 DOI: 10.1093/ajcp/64.3.311] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Evaluation in screening of hospitalized patients. Am J Clin Pathol 64: 311-314, 1975. The specificity of the serum gamma-glutamyl transpepidase (GGT) was evaluated by its determination in 1,040 unselected adult inpatients. GGT was elevated in 139 (13.4%) patients, but was only rarely elevated in the absence of elevation of other enzymes in the routine chemistry profile. Of the elevations, 32.4% occurred in patients with primary hepatobiliary disease. An elevated serum GGT is a strong indicator of hepatobiliary dysfunction. However, proper interpretation of a serum GGT elevation requires correlation with clinical data and other tests.
Collapse
|
|
50 |
14 |
23
|
Katz ME, Mcloon M, Burrows S, Cheetham BF. Extreme DNA sequence variation in isolates of Aspergillus fumigatus. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1998; 20:283-8. [PMID: 9626933 DOI: 10.1111/j.1574-695x.1998.tb01138.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
DNA sequence analysis of the alkaline protease gene was used to investigate two Aspergillus fumigatus strains isolated from ostriches (QLD1 and NSW3) and one environmental isolate (FRR 1266) that have shown genetic variation in previous analyses. The results showed that the QLD1 sequence was virtually identical to the published sequences for three human isolates but NSW3 differed in > 6% and FRR 1266 in > 10% of the nucleotides that were analysed. An RFLP assay was designed to determine the distribution of these (and other) genetic variants among environmental and clinical isolates of A. fumigatus.
Collapse
|
|
27 |
12 |
24
|
|
|
52 |
12 |
25
|
See VHL, Mas E, Prescott SL, Beilin LJ, Burrows S, Barden AE, Huang RC, Mori TA. Effects of postnatal omega-3 fatty acid supplementation on offspring pro-resolving mediators of inflammation at 6 months and 5 years of age: A double blind, randomized controlled clinical trial. Prostaglandins Leukot Essent Fatty Acids 2017; 126:126-132. [PMID: 29031390 DOI: 10.1016/j.plefa.2017.08.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 07/13/2017] [Accepted: 08/21/2017] [Indexed: 01/12/2023]
Abstract
BACKGROUND Resolution of inflammation is an active process involving specialised pro-resolving mediators (SPMs) generated from the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Omega-3 fatty acid supplementation during infancy may provide an intervention strategy to modify SPMs and reduce oxidative stress. This study evaluates the effect of omega-3 fatty acid supplementation in infancy on SPMs and F2-isoprostanes from 6 months to 5 years of age. METHODS In a double-blind, placebo-controlled, parallel-group study design, 420 infants were randomized to a daily supplement of omega-3 fatty acids (280mg DHA and 110mg EPA) or olive oil (control), from birth to age 6 months. Blood was collected at birth (cord blood), 6 months, 12 months and 5 years. Plasma SPMs included 18-HEPE, E-series resolvins, 17-HDHA, D-series resolvins, 14-HDHA, 10S,17S-DiHDoHE, MaR1 and PD1. F2-isoprostanes were measured in plasma and urine, as markers of oxidative stress in vivo. RESULTS The change in the concentration of 18-HEPE from birth to 6 months was greater in the omega-3 fatty acid group (Ptimepoint*group=0.04) with levels at 6 months significantly higher than controls (P=0.02). Other SPMs were not different between the groups at any time point. Plasma 18-HEPE concentration were associated with erythrocyte EPA concentrations after age and group adjustments (P<0.001), but not with allergic outcomes at 12 months. There were no between-group differences in plasma and urinary F2-isoprostanes at any time point. CONCLUSION Omega-3 fatty acid supplementation from birth to 6 months of age increased SPM at 6 months but the effects were not sustained after supplementation ceased. Given that 18-HEPE is a biologically active metabolite, future studies should examine how the increase in 18-HEPE relates to potential health benefits of omega-3 fatty acid supplementation in infancy.
Collapse
|
Randomized Controlled Trial |
8 |
11 |