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1.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33495345

RESUMO

Global and regional atmospheric measurements and modeling can play key roles in discovering and quantifying unexpected nascent emissions of environmentally important substances. We focus here on three hydrochlorofluorocarbons (HCFCs) that are restricted by the Montreal Protocol because of their roles in stratospheric ozone depletion. Based on measurements of archived air samples and on in situ measurements at stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, we report global abundances, trends, and regional enhancements for HCFC-132b ([Formula: see text]), which is newly discovered in the atmosphere, and updated results for HCFC-133a ([Formula: see text]) and HCFC-31 ([Formula: see text]ClF). No purposeful end-use is known for any of these compounds. We find that HCFC-132b appeared in the atmosphere 20 y ago and that its global emissions increased to 1.1 Gg⋅y-1 by 2019. Regional top-down emission estimates for East Asia, based on high-frequency measurements for 2016-2019, account for ∼95% of the global HCFC-132b emissions and for ∼80% of the global HCFC-133a emissions of 2.3 Gg⋅y-1 during this period. Global emissions of HCFC-31 for the same period are 0.71 Gg⋅y-1 Small European emissions of HCFC-132b and HCFC-133a, found in southeastern France, ceased in early 2017 when a fluorocarbon production facility in that area closed. Although unreported emissive end-uses cannot be ruled out, all three compounds are most likely emitted as intermediate by-products in chemical production pathways. Identification of harmful emissions to the atmosphere at an early stage can guide the effective development of global and regional environmental policy.

2.
Environ Health ; 22(1): 68, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794452

RESUMO

BACKGROUND: During deployment, veterans of the 1991 Gulf War (GW) were exposed to multiple war-related toxicants. Roughly a third of these veterans continue to exhibit neurotoxicant induced symptoms of Gulf War Illness (GWI), a multi-faceted condition that includes fatigue, pain and cognitive decrements. When studied empirically, both deployed veterans with exposures and those who meet the criteria for GWI are more likely to show deficits in the area of neuropsychological functioning. Although studies have shown cognitive impairments in small sample sizes, it is necessary to revisit these findings with larger samples and newer cohorts to see if other areas of deficit emerge with more power to detect such differences. A group of researchers and clinicians with expertise in the area of GWI have identified common data elements (CDE) for use in research samples to compare data sets. At the same time, a subgroup of researchers created a new repository to share these cognitive data and biospecimens within the GWI research community. METHODS: The present study aimed to compare cognitive measures of attention, executive functioning, and verbal memory in a large sample of GWI cases and healthy GW veteran controls using neuropsychological tests recommended in the CDEs. We additionally subdivided samples based on the specific neurotoxicant exposures related to cognitive deficits and compared exposed versus non-exposed veterans regardless of case criteria status. The total sample utilized cognitive testing outcomes from the newly collated Boston, Biorepository, Recruitment, and Integrative Network (BBRAIN) for GWI. RESULTS: Participants included 411 GW veterans, 312 GWI (cases) and 99 healthy veterans (controls). Veterans with GWI showed significantly poorer attention, executive functioning, learning, and short-and-long term verbal memory than those without GWI. Further, GW veterans with exposures to acetylcholinesterase inhibiting pesticides and nerve gas agents, had worse performance on executive function tasks. Veterans with exposure to oil well fires had worse performance on verbal memory and those with pyridostigmine bromide anti-nerve gas pill exposures had better verbal memory and worse performance on an attention task compared to unexposed veterans. CONCLUSIONS: This study replicates prior results regarding the utility of the currently recommended CDEs in determining impairments in cognitive functioning in veterans with GWI in a new widely-available repository cohort and provides further evidence of cognitive decrements in GW veterans related to war-related neurotoxicant exposures.


Assuntos
Síndrome do Golfo Pérsico , Veteranos , Humanos , Síndrome do Golfo Pérsico/induzido quimicamente , Síndrome do Golfo Pérsico/epidemiologia , Síndrome do Golfo Pérsico/psicologia , Guerra do Golfo , Boston/epidemiologia , Acetilcolinesterase , Cognição
3.
Clin Exp Dermatol ; 46(3): 438-443, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33180972

RESUMO

The role of neuroimaging in neurocutaneous disorders is an evolving field. Research can be inconsistent and inconclusive, leading to divergent practice for some disorders. This study provides an overview of the current role of magnetic resonance imaging (MRI) of the brain in select neurocutaneous disorders, namely Sturge-Weber syndrome, congenital melanocytic naevus syndrome, neurofibromatosis type 1, tuberous sclerosis complex, incontinentia pigmenti and basal cell naevus syndrome. Future research assessing new targeted treatments and novel MRI techniques may change current practice.


Assuntos
Imageamento por Ressonância Magnética , Síndromes Neurocutâneas/diagnóstico por imagem , Neuroimagem , Síndrome do Nevo Basocelular/diagnóstico por imagem , Criança , Humanos , Incontinência Pigmentar/diagnóstico por imagem , Lactente , Imageamento por Ressonância Magnética/efeitos adversos , Neurofibromatose 1/diagnóstico por imagem , Neuroimagem/efeitos adversos , Nevo Pigmentado/diagnóstico por imagem , Fatores de Risco , Neoplasias Cutâneas/diagnóstico por imagem , Síndrome de Sturge-Weber/diagnóstico por imagem , Esclerose Tuberosa/diagnóstico por imagem
4.
Clin Exp Dermatol ; 46(4): 715-719, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33548070

RESUMO

Since the last assessment of conflicts of interest (COIs) in dermatology randomized controlled trials (RCTs) in 2004, several countries have introduced transparency databases. We assessed the prevalence of financial COIs in dermatology RCTs and quantified payments from study sponsors to academic/clinical authors using transparency databases, which are available in the USA, France, Australia, Belgium and the Netherlands, while the UK has a noncompulsory transparency database. We included RCTs from the top 10 dermatology journals and the top 7 general medical journals published in 2019. The study assessed 83 RCTs, and COIs were identified in 69%. The highest prevalence was in exclusively industry-funded trials (46/47, 98%), which consisted of personal payments to an academic/clinical author (96% of trials) and having authors who were employees/stockholders (96%). Payments were identified for 31/56 (55%) academic/clinical first/final authors (median payment US$28 746, maximum US$597 299, interquartile range US$17 061-146 253), and 24/31 payments (77%) payments were each > US$10 000.


Assuntos
Conflito de Interesses/economia , Dermatologia/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Apoio à Pesquisa como Assunto/ética , Pesquisa Biomédica/ética , Estudos Transversais , Humanos
5.
Clin Exp Dermatol ; 46(6): 1086-1088, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33914938

RESUMO

Medical writers may make major contributions to the preparation of a manuscript, but are not listed as authors. We assessed the prevalence, affiliation and role of medical writers in dermatology randomized controlled trials (RCTs) published in 2019 in the top 7 medical and top 10 dermatology journals. Medical writers were identified in 39/83 trials (47%), all of which were exclusively industry-funded trials (39/47, prevalence 83%). Most studies stated their role as 'medical writing support' and/or 'editorial assistance' (35/39, 90%), but when more information was provided, four studies specified first draft preparation (50% of RCTs in general medical and 1.3% of RCTs in dermatology journals). Medical writers are common in dermatology trials but their role is often vaguely stated. In April 2020 the British Journal or Dermatology and Clinical and Experimental Dermatology adopted CRediT (Contributor Roles Taxonomy), which describes contributions of authors and may help clarify who writes trial manuscripts.


Assuntos
Autoria , Dermatologia , Escrita Médica , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Jornalismo Médico , Publicações Periódicas como Assunto
6.
Clin Exp Dermatol ; 46(7): 1290-1292, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33608909

RESUMO

Recent meta-analyses of Janus kinase (JAK) inhibitors in alopecia areata (AA) have excluded trial registries and may thus be subject to publication bias. This study assessed the potential for evidence selection bias and provides an overview of JAK inhibitor trials in AA. A broad search strategy of ClinicalTrials.gov was performed for AA. We also recorded whether results were published on PubMed. There were 26 trials identified, of which 9 were ongoing (mostly oral JAK inhibitors: 8 studies; 89%). Of completed/terminated trials, 4/17 (24%) had terminated prematurely, citing 'inefficacy/futility' or 'sponsor decision'. These were all topical JAK inhibitor trials (4/8, 50% termination rate), with a 0% termination rate (0/9) for oral JAK inhibitor trials. We conclude that topical JAK inhibitors may be less efficacious than has been apparent in the literature to date, with 50% of trials having terminated due to inefficacy/futility or sponsor decision and only one topical JAK inhibitor trial ongoing.


Assuntos
Alopecia em Áreas/tratamento farmacológico , Ensaios Clínicos como Assunto , Inibidores de Janus Quinases/uso terapêutico , Viés de Publicação , Sistema de Registros , Bases de Dados Factuais , Término Precoce de Ensaios Clínicos , Humanos , Metanálise como Assunto , Falha de Tratamento
7.
Nature ; 513(7517): 219-23, 2014 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-25209800

RESUMO

The hydroxyl radical (OH) is a key oxidant involved in the removal of air pollutants and greenhouse gases from the atmosphere. The ratio of Northern Hemispheric to Southern Hemispheric (NH/SH) OH concentration is important for our understanding of emission estimates of atmospheric species such as nitrogen oxides and methane. It remains poorly constrained, however, with a range of estimates from 0.85 to 1.4 (refs 4, 7-10). Here we determine the NH/SH ratio of OH with the help of methyl chloroform data (a proxy for OH concentrations) and an atmospheric transport model that accurately describes interhemispheric transport and modelled emissions. We find that for the years 2004-2011 the model predicts an annual mean NH-SH gradient of methyl chloroform that is a tight linear function of the modelled NH/SH ratio in annual mean OH. We estimate a NH/SH OH ratio of 0.97 ± 0.12 during this time period by optimizing global total emissions and mean OH abundance to fit methyl chloroform data from two surface-measurement networks and aircraft campaigns. Our findings suggest that top-down emission estimates of reactive species such as nitrogen oxides in key emitting countries in the NH that are based on a NH/SH OH ratio larger than 1 may be overestimated.


Assuntos
Atmosfera/química , Radical Hidroxila/química , Modelos Teóricos , Poluentes Atmosféricos/química , Clorofórmio/química , Simulação por Computador , Óxidos de Nitrogênio/química
8.
Proc Natl Acad Sci U S A ; 114(21): 5373-5377, 2017 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-28416657

RESUMO

The growth in global methane (CH4) concentration, which had been ongoing since the industrial revolution, stalled around the year 2000 before resuming globally in 2007. We evaluate the role of the hydroxyl radical (OH), the major CH4 sink, in the recent CH4 growth. We also examine the influence of systematic uncertainties in OH concentrations on CH4 emissions inferred from atmospheric observations. We use observations of 1,1,1-trichloroethane (CH3CCl3), which is lost primarily through reaction with OH, to estimate OH levels as well as CH3CC3 emissions, which have uncertainty that previously limited the accuracy of OH estimates. We find a 64-70% probability that a decline in OH has contributed to the post-2007 methane rise. Our median solution suggests that CH4 emissions increased relatively steadily during the late 1990s and early 2000s, after which growth was more modest. This solution obviates the need for a sudden statistically significant change in total CH4 emissions around the year 2007 to explain the atmospheric observations and can explain some of the decline in the atmospheric 13CH4/12CH4 ratio and the recent growth in C2H6 Our approach indicates that significant OH-related uncertainties in the CH4 budget remain, and we find that it is not possible to implicate, with a high degree of confidence, rapid global CH4 emissions changes as the primary driver of recent trends when our inferred OH trends and these uncertainties are considered.

9.
Proc Natl Acad Sci U S A ; 112(19): 5927-31, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25918401

RESUMO

We infer global and regional emissions of five of the most abundant hydrofluorocarbons (HFCs) using atmospheric measurements from the Advanced Global Atmospheric Gases Experiment and the National Institute for Environmental Studies, Japan, networks. We find that the total CO2-equivalent emissions of the five HFCs from countries that are required to provide detailed, annual reports to the United Nations Framework Convention on Climate Change (UNFCCC) increased from 198 (175-221) Tg-CO2-eq ⋅ y(-1) in 2007 to 275 (246-304) Tg-CO2-eq ⋅ y(-1) in 2012. These global warming potential-weighted aggregated emissions agree well with those reported to the UNFCCC throughout this period and indicate that the gap between reported emissions and global HFC emissions derived from atmospheric trends is almost entirely due to emissions from nonreporting countries. However, our measurement-based estimates of individual HFC species suggest that emissions, from reporting countries, of the most abundant HFC, HFC-134a, were only 79% (63-95%) of the UNFCCC inventory total, while other HFC emissions were significantly greater than the reported values. These results suggest that there are inaccuracies in the reporting methods for individual HFCs, which appear to cancel when aggregated together.

11.
Epidemiol Infect ; 144(11): 2440-6, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26996433

RESUMO

Although community-onset bloodstream infection (BSI) is recognized as a major cause of morbidity and mortality, its epidemiology has not been well defined in non-selected populations. We conducted population-based surveillance in the Interior Health West region of British Columbia, Canada in order to determine the burden associated with community-onset BSI. A total of 1088 episodes were identified for an overall annual incidence of 117·8/100 000 of which 639 (58·7%) were healthcare-associated (HA) and 449 (41·3%) were community-associated (CA) BSIs for incidences of 69·2 and 48·6/100 000, respectively. The incidence of community-onset BSI varied by age and gender and elderly males were at the highest risk. Overall 964 (88·6%) episodes resulted in hospital admission for a median length of stay of 8 days; the total days of acute hospitalization associated with community-onset BSI was 13 530 days or 1465 days/100 000 population per year. The in-hospital mortality rate was 10·6% (102/964) and this was higher for HA-BSI (72/569, 12·7%) compared to CA-BSI (30/395, 7·6%, P = 0·014) episodes. Community-onset BSI, especially HA-BSI, is associated with a major burden of illness.


Assuntos
Bacteriemia/epidemiologia , Infecção Hospitalar/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Colúmbia Britânica/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Vigilância da População , Fatores Sexuais
16.
Proc Natl Acad Sci U S A ; 110(6): 2029-34, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23341630

RESUMO

Nitrogen trifluoride (NF(3)) has potential to make a growing contribution to the Earth's radiative budget; however, our understanding of its atmospheric burden and emission rates has been limited. Based on a revision of our previous calibration and using an expanded set of atmospheric measurements together with an atmospheric model and inverse method, we estimate that the global emissions of NF(3) in 2011 were 1.18 ± 0.21 Gg⋅y(-1), or ∼20 Tg CO(2)-eq⋅y(-1) (carbon dioxide equivalent emissions based on a 100-y global warming potential of 16,600 for NF(3)). The 2011 global mean tropospheric dry air mole fraction was 0.86 ± 0.04 parts per trillion, resulting from an average emissions growth rate of 0.09 Gg⋅y(-2) over the prior decade. In terms of CO(2) equivalents, current NF(3) emissions represent between 17% and 36% of the emissions of other long-lived fluorinated compounds from electronics manufacture. We also estimate that the emissions benefit of using NF(3) over hexafluoroethane (C(2)F(6)) in electronics manufacture is significant-emissions of between 53 and 220 Tg CO(2)-eq⋅y(-1) were avoided during 2011. Despite these savings, total NF(3) emissions, currently ∼10% of production, are still significantly larger than expected assuming global implementation of ideal industrial practices. As such, there is a continuing need for improvements in NF(3) emissions reduction strategies to keep pace with its increasing use and to slow its rising contribution to anthropogenic climate forcing.

17.
Hum Reprod ; 30(6): 1365-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25908658

RESUMO

STUDY QUESTION: What are the experiences of trans persons (i.e. those whose gender identity does not match the gender assigned to them at birth) who sought or accessed assisted reproduction (AR) services in Ontario, Canada, between 2007 and 2010? SUMMARY ANSWER: The majority of trans persons report negative experiences with AR service providers. WHAT IS KNOWN ALREADY: Apart from research examining desire to have children among trans people, most of the literature on this topic has debated the ethics of assisting trans persons to become parents. To-date, all of the published research concerning trans persons' experiences with AR services is solely from the perspective of service providers; no studies have examined the experiences of trans people themselves. STUDY DESIGN, SIZE, DURATION: Secondary qualitative research study of data from nine trans-identified people and their partners (total n = 11) collected as part of a community-based study of access to AR services for sexual and gender minority people between 2010 and 2012. PARTICIPANTS/MATERIALS, SETTING, METHODS: Trans-identified volunteers (and their partners, when applicable) who had used or attempted to access AR services since 2007 from across Ontario, Canada, participated in a 60-90 minute, semi-structured qualitative interview. Qualitative analysis was performed using a descriptive phenomenological approach. Emerging themes were continually checked against the data as part of an iterative process. MAIN RESULTS AND THE ROLE OF CHANCE: The data highlight barriers to accessing AR services for trans people. Participant recommendations for improving AR service provision to better meet the needs of this population are presented. These recommendations address the following areas: (i) AR service provider education and training; (ii) service provider and clinic practices and (iii) clinic environment. LIMITATIONS, REASONS FOR CAUTION: The majority of study participants were trans people who identified as men and who resided in major urban areas; those living in smaller communities may have different experiences that were not adequately captured in this analysis. WIDER IMPLICATIONS OF THE FINDINGS: While existing literature debates the ethics of assisting trans people to become parents through the use of AR, our study demonstrates that they are already accessing or attempting to access these services. This reality necessitates a shift toward exploring the ways in which AR services can be improved to better meet the needs of this population, from the perspectives of both service users and service providers. STUDY FUNDING/COMPETING INTERESTS: This project was supported by the Canadian Institutes of Health Research-Institute of Gender and Health, in partnership with the Assisted Human Reproduction Canada: Catalyst Grant: Psychosocial Issues Associated with Assisted Human Reproduction (FRN-103595). S.M. was supported by a Canada Graduate Scholarship from the Social Science and Humanities Research Council, as well as research funding from Osgoode Hall Law School, York University. S.J.-A. was supported by an Ontario Graduate Scholarship funded by the Province of Ontario and the University of Toronto. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Acessibilidade aos Serviços de Saúde , Técnicas de Reprodução Assistida/ética , Pessoas Transgênero/psicologia , Adulto , Canadá , Feminino , Identidade de Gênero , Humanos , Masculino , Pessoa de Meia-Idade
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