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2.
HardwareX ; 9: e00163, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35492063

RESUMO

An open-source potentiostat/galvanostat instrument design is introduced that provides the ability to take accurate measurements over a current range of ±200 mA and a potential range of ±12 V. The improved capability of the instrument compared to the previously published design upon which it is based makes it suitable for performing a wider range of electrochemical measurements including the ability to use larger working electrodes, study of high current density processes, study of electrochemistry in nonaqueous solutions and use in high voltage processes such as electrophoretic deposition. The instrument can be controlled from any computer capable of running the Python programming language, including a low-cost Raspberry Pi. Unlike many commercial potentiostat designs, the instrument is completely open-source, giving researchers the ability to modify the hardware and software as needed for custom measurement techniques. The low cost makes the instrument attractive for research and teaching laboratories in which multiple electrochemical measurements need to be carried out in parallel.

3.
Mol Ecol ; 30(13): 3068-3082, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32638451

RESUMO

Organism abundance is a critical parameter in ecology, but its estimation is often challenging. Approaches utilizing eDNA to indirectly estimate abundance have recently generated substantial interest. However, preliminary correlations observed between eDNA concentration and abundance in nature are typically moderate in strength with significant unexplained variation. Here, we apply a novel approach to integrate allometric scaling coefficients into models of eDNA concentration and organism abundance. We hypothesize that eDNA particle production scales nonlinearly with mass, with scaling coefficients < 1. Wild populations often exhibit substantial variation in individual body size distributions; we therefore predict that the distribution of mass across individuals within a population will influence population-level eDNA production rates. To test our hypothesis, we collected standardized body size distribution and mark-recapture abundance data using whole-lake experiments involving nine populations of brook trout. We correlated eDNA concentration with three metrics of abundance: density (individuals/ha), biomass (kg/ha) and allometrically scaled mass (ASM) (∑(individual mass0.73 )/ha). Density and biomass were both significantly positively correlated with eDNA concentration (adj. r2  = 0.59 and 0.63, respectively), but ASM exhibited improved model fit (adj. r2  = 0.78). We also demonstrate how estimates of ASM derived from eDNA samples in "unknown" systems can be converted to biomass or density estimates with additional size-structure data. Future experiments should empirically validate allometric scaling coefficients for eDNA production, particularly where substantial intraspecific size distribution variation exists. Incorporating allometric scaling may improve predictive models to the extent that eDNA concentration may become a reliable indicator of abundance in nature.


Assuntos
Lagos , Truta , Animais , Biomassa , Tamanho Corporal
4.
Br J Dermatol ; 185(1): 80-90, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33368145

RESUMO

BACKGROUND: Registry data suggest that people with immune-mediated inflammatory diseases (IMIDs) receiving targeted systemic therapies have fewer adverse coronavirus disease 2019 (COVID-19) outcomes compared with patients receiving no systemic treatments. OBJECTIVES: We used international patient survey data to explore the hypothesis that greater risk-mitigating behaviour in those receiving targeted therapies may account, at least in part, for this observation. METHODS: Online surveys were completed by individuals with psoriasis (globally) or rheumatic and musculoskeletal diseases (RMDs) (UK only) between 4 May and 7 September 2020. We used multiple logistic regression to assess the association between treatment type and risk-mitigating behaviour, adjusting for clinical and demographic characteristics. We characterized international variation in a mixed-effects model. RESULTS: Of 3720 participants (2869 psoriasis, 851 RMDs) from 74 countries, 2262 (60·8%) reported the most stringent risk-mitigating behaviour (classified here under the umbrella term 'shielding'). A greater proportion of those receiving targeted therapies (biologics and Janus Kinase inhibitors) reported shielding compared with those receiving no systemic therapy [adjusted odds ratio (OR) 1·63, 95% confidence interval (CI) 1·35-1·97]. The association between targeted therapy and shielding was preserved when standard systemic therapy was used as the reference group (OR 1·39, 95% CI 1·23-1·56). Shielding was associated with established risk factors for severe COVID-19 [male sex (OR 1·14, 95% CI 1·05-1·24), obesity (OR 1·37, 95% CI 1·23-1·54), comorbidity burden (OR 1·43, 95% CI 1·15-1·78)], a primary indication of RMDs (OR 1·37, 95% CI 1·27-1·48) and a positive anxiety or depression screen (OR 1·57, 95% CI 1·36-1·80). Modest differences in the proportion shielding were observed across nations. CONCLUSIONS: Greater risk-mitigating behaviour among people with IMIDs receiving targeted therapies may contribute to the reported lower risk of adverse COVID-19 outcomes. The behaviour variation across treatment groups, IMIDs and nations reinforces the need for clear evidence-based patient communication on risk-mitigation strategies and may help inform updated public health guidelines as the pandemic continues.


Assuntos
COVID-19 , Artropatias , Estudos Transversais , Humanos , Masculino , Pandemias , SARS-CoV-2
5.
Proc Biol Sci ; 286(1916): 20191989, 2019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31771476

RESUMO

Little empirical work in nature has quantified how wild populations with varying effective population sizes and genetic diversity perform when exposed to a gradient of ecologically important environmental conditions. To achieve this, juvenile brook trout from 12 isolated populations or closed metapopulations that differ substantially in population size and genetic diversity were transplanted to previously fishless ponds spanning a wide gradient of ecologically important variables. We evaluated the effect of genome-wide variation, effective population size (Ne), pond habitat, and initial body size on two fitness correlates (survival and growth). Genetic variables had no effect on either fitness correlate, which was determined primarily by habitat (pond temperature, depth, and pH) and initial body size. These results suggest that some vertebrate populations with low genomic diversity, low Ne, and long-term isolation can represent important sources of variation and are capable of maintaining fitness in, and ultimately persisting and adapting to, changing environments. Our results also reinforce the paramount importance of improving available habitat and slowing habitat degradation for species conservation.


Assuntos
Variação Genética , Truta/genética , Animais , Ecossistema , Genética Populacional , Densidade Demográfica
6.
Obes Sci Pract ; 5(2): 159-167, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31019733

RESUMO

OBJECTIVE: Evidence of the association between childhood obesity and neighbourhood crime is inconclusive. Most previous studies have included children of all ages, and few have examined different types of crime. The objective of this study was to investigate the association between obesity and eight different types of crime (i.e. commercial robbery, street robbery, assault, other violence, commercial break and enter, residential break and enter, theft of vehicle and theft from vehicle) among 4- to 7-year-old children in a large western Canadian city. METHODS: Cross-sectional, epidemiological study (N = 10,069) using spatial analysis and hierarchical generalized linear modelling. The outcome variable was normal weight or obesity. The exposure variable was the distance between the child's residential postal code and the closest occurrence of each type of crime. RESULTS: Controlling for distance to the closest park, frequency of each type of crime in the child's neighbourhood and neighbourhood factors (proportion of visible minorities, education and median family income), there was no association between any of the crime types and childhood obesity. CONCLUSIONS: Crime did not contribute to obesity in this sample of 4- to 7-year-old children. Replication of this study in other jurisdictions would increase confidence in these results.

9.
Prog Biophys Mol Biol ; 130(Pt B): 365-375, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28587763

RESUMO

Mechano-electric feedback (MEF) is an established mechanism whereby myocardial deformation causes changes in cardiac electrophysiological parameters. Extensive animal, laboratory and theoretical investigation has demonstrated that abnormal patterns of cardiac strain can induce alteration of electrical excitation and recovery through MEF, which can potentially contribute to the establishment of dangerous arrhythmias. However, the clinical relevance of MEF in patients with heart disease remains to be established. This paper reviews up-to date experimental evidence describing the response to different types of mechanical stimuli in the intact human heart with the support of new data collected during cardiac surgery. It discusses modulatory effects of MEF that may contribute to increase the vulnerability to arrhythmia and describes MEF interaction with clinical conditions where mechanically induced changes in cardiac electrophysiology are likely to be more relevant. Finally, directions for future studies, including the need for in-vivo human data providing simultaneous assessment of the distribution of structural, functional and electrophysiological parameters at the regional level, are identified.


Assuntos
Fenômenos Eletrofisiológicos , Retroalimentação Fisiológica , Fenômenos Mecânicos , Animais , Arritmias Cardíacas/fisiopatologia , Humanos
11.
Ann Rheum Dis ; 75(9): 1583-94, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27338776

RESUMO

In this article, the 2009 European League Against Rheumatism (EULAR) recommendations for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) have been updated. The 2009 recommendations were on the management of primary small and medium vessel vasculitis. The 2015 update has been developed by an international task force representing EULAR, the European Renal Association and the European Vasculitis Society (EUVAS). The recommendations are based upon evidence from systematic literature reviews, as well as expert opinion where appropriate. The evidence presented was discussed and summarised by the experts in the course of a consensus-finding and voting process. Levels of evidence and grades of recommendations were derived and levels of agreement (strengths of recommendations) determined. In addition to the voting by the task force members, the relevance of the recommendations was assessed by an online voting survey among members of EUVAS. Fifteen recommendations were developed, covering general aspects, such as attaining remission and the need for shared decision making between clinicians and patients. More specific items relate to starting immunosuppressive therapy in combination with glucocorticoids to induce remission, followed by a period of remission maintenance; for remission induction in life-threatening or organ-threatening AAV, cyclophosphamide and rituximab are considered to have similar efficacy; plasma exchange which is recommended, where licensed, in the setting of rapidly progressive renal failure or severe diffuse pulmonary haemorrhage. These recommendations are intended for use by healthcare professionals, doctors in specialist training, medical students, pharmaceutical industries and drug regulatory organisations.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Gerenciamento Clínico , Imunossupressores/uso terapêutico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Biópsia/normas , Humanos , Troca Plasmática , Recidiva , Indução de Remissão/métodos , Retratamento/métodos
12.
J Food Sci ; 81(6): S1495-505, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27163714

RESUMO

Tomatoes (Solanum lycoperiscum) are a popular produce choice and provide many bioactive compounds. Consumer choice of tomatoes is influenced by flavor and visual appearance and external texture cues including hand firmness and sliceability. The objective of this study was to determine drivers of liking for fresh tomatoes across 3 stages of consumption. Seven tomato cultivars were ripened to a 6 on the USDA color chart. Trained panelists documented appearance, flavor, and texture attributes of tomatoes in triplicate. Tomato consumers (n = 177) were provided with knives and cutting boards and evaluated tomatoes across 3 stages: appearance (stage 1), slicing (stage 2), and consumption (stage 3). Consumers evaluated overall liking at each stage. Analysis of variance and external preference mapping were conducted. Overall liking was highest during the appearance portion of the test and lowest during the consumption portion (P < 0.05). Drivers of liking at stage 1 were color intensity, even outside color, and overall aroma. Drivers of liking at stage 2 were wetness/juiciness and overall aroma. Wetness/juiciness, seed presence, ripe flavor, and sweet and umami tastes were drivers of liking for tomatoes at consumption (stage 3). Four separate clusters of tomato consumers were identified. Cluster 1 preferred tomatoes with even color, higher color intensity, and flavor intensity. Cluster 2 preferred firm tomatoes. Cluster 3 preferred tomatoes that were soft and at peak ripeness; this cluster also had the highest liking scores for all tomatoes. Cluster 4 consumers generally consumed tomatoes in sandwiches rather than as-is and preferred tomatoes with even and intense color. Tomato growers can utilize these results to target cultivars that are well liked by consumers.


Assuntos
Cor , Solanum lycopersicum/química , Paladar , Adolescente , Adulto , Idoso , Comportamento de Escolha , Análise por Conglomerados , Comportamento do Consumidor , Feminino , Preferências Alimentares , Humanos , Solanum lycopersicum/classificação , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
15.
J R Coll Physicians Edinb ; 44(1): 4-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995438

RESUMO

When Bridget Driscoll, a 44-year-old mother of two died after being struck by a motor vehicle, considered to be the first motor vehicle fatality in UK and possibly the world, the coroner stated 'I trust this sort of nonsense will never happen again'.1 Sadly, the coroner, medical practitioners and general public would be deeply and repeatedly disappointed. It was 1896. Motor vehicles were a curiosity. Drivers did not undergo any form of testing, be it medical fitness, driving ability or otherwise, and there were no licensing regulatory agencies. By 2010, road injury was the ninth most common cause of death globally (1.3 million deaths per annum) and dementia the fourth most common in high income countries.2 By 2030 the number of all licensed UK drivers who are 65 years or older will increase by almost 50% to almost one in every four drivers.3 If the juxtaposition of driving with dementia in an ageing population is not already a contentious social, political and medical issue, it certainly will become so.


Assuntos
Acidentes de Trânsito/prevenção & controle , Condução de Veículo , Demência , Papel do Médico , Idoso , Feminino , Humanos , Masculino , Segurança , Reino Unido
16.
Intern Med J ; 44(2): 190-4, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24528815

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality in Australia. While there is well-established evidence for the use of VTE prophylaxis in hospital inpatients, adherence to such guidelines is poor. AIM: The aim of the present study is to assess the impact of education and system change on improving rates of VTE prophylaxis in hospital inpatients. METHODS: We performed four consecutive audits of inpatient medical records of a regional hospital service over 2 years. The audits aimed to test the impact of serial interventions at increasing the appropriate use of VTE prophylaxis (based on risk assessment). The interventions were (i) staff education and (ii) a process change that mandated a prophylaxis decision by modifying the National Inpatient Medication Chart with 'VTE avoidance' preprinted in the first medication box. RESULTS: Our results from the baseline study showed that of the 236 medical inpatients reviewed, 80% were at high risk of VTE. Of this high-risk cohort, 34.9% (confidence interval (CI) 28-42%) had appropriate prophylaxis decisions. Post the education intervention, 43.2% (CI 37-49%) of the high-risk cohort received appropriate VTE prophylaxis, an improvement of 8.3% (CI -1% to 18%) from baseline. With the subsequent introduction of a process change, 82.1% (CI 66-92%) of the high-risk cohort received appropriate prophylaxis, an improvement of 47.2% and 38.8% (CI 24-54%) when compared with baseline and education respectively. Retention rates at 11 months postsystem change were 73% (CI 55-86%). CONCLUSIONS: This study therefore concluded that while education has an impact on rates of appropriate VTE prophylaxis, it is system change that has the most marked and sustained effect.


Assuntos
Anticoagulantes/uso terapêutico , Quimioprevenção , Prontuários Médicos , Desenvolvimento de Pessoal/organização & administração , Tromboembolia Venosa/prevenção & controle , Idoso , Austrália , Quimioprevenção/enfermagem , Quimioprevenção/normas , Auditoria Clínica , Feminino , Controle de Formulários e Registros , Fidelidade a Diretrizes , Humanos , Pacientes Internados/estatística & dados numéricos , Masculino , Prontuários Médicos/normas , Prontuários Médicos/estatística & dados numéricos , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Melhoria de Qualidade , Medição de Risco , Fatores de Risco
17.
Clin Rheumatol ; 33(2): 227-36, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24026674

RESUMO

To conduct a meta-analysis of published data of the effectiveness of drug treatment in giant cell arteritis (GCA) to provide evidence to support the optimal use of glucocorticoids (GCs) and adjunct therapy. MEDLINE, CENTRAL and EMBASE searches were used to identify randomised control trials on the treatment of GCA. Studies included were trials in which: (1) the participants were classified as having GCA by the 1990 ACR criteria or biopsy proven disease; (2) parallel-group randomised control of at least 16 weeks duration had been conducted with at least 20 participants; (3) the design included either alternative adjunct immunosuppressant regimens, alternative GCs dosing or routes of administration; and (4) outcome data was included on either relapse rates or rates of infection. One thousand eight hundred thirty-six articles were retrieved, of which only 37 met the primary inclusion criteria. Sixteen of these studies reported some information about the GCs or adjuvant regimen used. Only ten studies were of sufficient quality to be included in the meta-analysis. Together these comprised 638 participants of which 72 % were female. Three studies compared various GCs regimens, with two comparing IV GCs, the latter showing a marginal benefit with respect to relapse (risk ratio (RR) = 0.78, 95 % CI = 0.54 to 1.12) but a greater risk of infection (RR = 1.58, 95 % CI = 0.90 to 2.78). Another three used methotrexate as an adjunctive agent and showed marginal benefit with respect to relapse (RR = 0.85, 95 % CI = 0.66 to 1.11). The remaining four trials compared prednisolone to dapsone, infliximab, adalimumab and hydroxychloroquine, respectively. There are various clinical trials of varying quality. The results from this meta-analysis show that the use of adjunct agents is not associated with improved outcome.


Assuntos
Arterite de Células Gigantes/tratamento farmacológico , Terapia de Imunossupressão/métodos , Imunossupressores/administração & dosagem , Prednisolona/administração & dosagem , Adalimumab , Anti-Inflamatórios/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Dapsona/administração & dosagem , Feminino , Humanos , Hidroxicloroquina/administração & dosagem , Infliximab , Masculino , Metotrexato/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Indução de Remissão , Resultado do Tratamento , Vasculite/tratamento farmacológico
18.
Genet Mol Res ; 12(4): 4549-58, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24222230

RESUMO

Sugarcane is an economically important culture in Brazil. Endophytic bacteria live inside plants, and can provide many benefits to the plant host. We analyzed the bacterial diversity of sugarcane cultivar RB-72454 by cultivation-independent techniques. Total DNA from sugarcane stems from a commercial plantation located in Paraná State was extracted. Partial 16S rRNA genes were amplified and sequenced for library construction. Of 152 sequences obtained, 52% were similar to 16S rRNA from Pseudomonas sp, and 35.5% to Enterobacter sp. The genera Pantoea, Serratia, Citrobacter, and Klebsiella were also represented. The endophytic communities in these sugarcane samples were dominated by the families Enterobacteriaceae and Pseudomonadaceae (class Gammaproteobacteria).


Assuntos
Endófitos/genética , Enterobacteriaceae/genética , Pseudomonadaceae/genética , Saccharum/microbiologia , Técnicas de Cultura , Tipagem Molecular , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
19.
Microbiology (Reading) ; 159(Pt 1): 167-175, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23125118

RESUMO

Several bacteria are able to degrade flavonoids either to use them as carbon sources or as a detoxification mechanism. Degradation pathways have been proposed for several bacteria, but the genes responsible are not known. We identified in the genome of the endophyte Herbaspirillum seropedicae SmR1 an operon potentially associated with the degradation of aromatic compounds. We show that this operon is involved in naringenin degradation and that its expression is induced by naringenin and chrysin, two closely related flavonoids. Mutation of fdeA, the first gene of the operon, and fdeR, its transcriptional activator, abolished the ability of H. seropedicae to degrade naringenin.


Assuntos
Flavanonas/metabolismo , Herbaspirillum/metabolismo , Proteínas de Bactérias/genética , Biotransformação , Flavonoides/metabolismo , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Herbaspirillum/genética , Óperon
20.
Braz. j. med. biol. res ; 45(12): 1127-1134, Dec. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-659650

RESUMO

DNA repair is crucial to the survival of all organisms. The bacterial RecA protein is a central component in the SOS response and in recombinational and SOS DNA repairs. The RecX protein has been characterized as a negative modulator of RecA activity in many bacteria. The recA and recX genes of Herbaspirillum seropedicae constitute a single operon, and evidence suggests that RecX participates in SOS repair. In the present study, we show that the H. seropedicae RecX protein (RecX Hs) can interact with the H. seropedicaeRecA protein (RecA Hs) and that RecA Hs possesses ATP binding, ATP hydrolyzing and DNA strand exchange activities. RecX Hs inhibited 90% of the RecA Hs DNA strand exchange activity even when present in a 50-fold lower molar concentration than RecA Hs. RecA Hs ATP binding was not affected by the addition of RecX, but the ATPase activity was reduced. When RecX Hs was present before the formation of RecA filaments (RecA-ssDNA), inhibition of ATPase activity was substantially reduced and excess ssDNA also partially suppressed this inhibition. The results suggest that the RecX Hs protein negatively modulates the RecA Hs activities by protein-protein interactions and also by DNA-protein interactions.


Assuntos
Proteínas de Bactérias/metabolismo , Herbaspirillum/química , Recombinases Rec A/metabolismo , DNA Bacteriano , Escherichia coli/metabolismo , Ligação Proteica
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