Per-alkoxy-pillar[5]arenes as electron donors: Electrochemical properties of dimethoxy-pillar[5]arene and its corresponding rotaxane

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). 1,4-dimethoxypillar[5]arene undergoes reversible multielectron oxidations forming stable radical cations, a property retained when incorporated in [2]rotaxanes, suggesting that pillar[5]arenes can be employed as viable, yet unreported, electron donors

Genetic risk of obesity as a modifier of associations between neighbourhood environment and body mass index: an observational study of 335 046 UK Biobank participants.

BackgroundThere is growing recognition that recent global increases in obesity are the product of a complex interplay between genetic and environmental factors. However, in gene-environment studies of obesity, 'environment' usually refers to individual behavioural factors that influence energy balance, whereas more upstream environmental factors are overlooked. We examined gene-environment interactions between genetic risk of obesity and two neighbourhood characteristics likely to be associated with obesity (proximity to takeaway/fast-food outlets and availability of physical activity facilities).MethodsWe used data from 335 046 adults aged 40-70 in the UK Biobank cohort to conduct a population-based cross-sectional study of interactions between neighbourhood characteristics and genetic risk of obesity, in relation to body mass index (BMI). Proximity to a fast-food outlet was defined as distance from home address to nearest takeaway/fast-food outlet, and availability of physical activity facilities as the number of formal physical activity facilities within 1 km of home address. Genetic risk of obesity was operationalised by weighted Genetic Risk Scores of 91 or 69 single nucleotide polymorphisms (SNP), and by six individual SNPs considered separately. Multivariable, mixed-effects models with product terms for the gene-environment interactions were estimated.ResultsAfter accounting for likely confounding, the association between proximity to takeaway/fast-food outlets and BMI was stronger among those at increased genetic risk of obesity, with evidence of an interaction with polygenic risk scores (p=0.018 and p=0.028 for 69-SNP and 91-SNP scores, respectively) and in particular with a SNP linked to MC4R (p=0.009), a gene known to regulate food intake. We found very little evidence of gene-environment interaction for the availability of physical activity facilities.ConclusionsIndividuals at an increased genetic risk of obesity may be more sensitive to exposure to the local fast-food environment. Ensuring that neighbourhood residential environments are designed to promote a healthy weight may be particularly important for those with greater genetic susceptibility to obesity

Do neighbourhood characteristics act together to influence BMI? A cross-sectional study of urban parks and takeaway/fast-food stores as modifiers of the effect of physical activity facilities

Studies exploring associations between neighbourhood environment and obesity often overlook the fact that neighbourhoods are multi-dimensional and that the effects of one environmental exposure may be modified by another. We examine whether associations between neighbourhood density of formal physical activity (PA) facilities and body mass index (BMI) are modified by the density of neighbourhood green spaces and takeaway stores. We used cross-sectional data from the UK Biobank cohort and linked UK Biobank Urban Morphometric Platform (UKBUMP) for 345,269 urban-dwelling adults aged 40-69. We examined associations between objectively measured BMI and the number of formal PA facilities (gyms, pools, etc.) within 1 km of each individual's home, testing separately for interactions with the number of local public green spaces, and number of takeaway stores, within the same 1 km buffers. We estimated modifier-stratified associations using multivariable, multilevel models to account for a clustered sampling design and potential confounding. Likelihood ratio tests were used to assess statistical interaction. We found that the association between a greater number of local PA facilities and lower BMI was stronger among people with fewer urban green spaces in their neighbourhood than among those with more green spaces (Pinteraction = 0.021). The same relationship between PA facilities and BMI was also noticeably attenuated among those with more takeaway stores near home, compared with people with none (Pinteraction = 0.014). We conclude that formal PA facilities may buffer against a lack of informal, green resources for PA in areas where the latter are scarce. However, the potential benefits of formal PA facilities in terms of obesity risk may be undermined by an unhealthy food environment close to home. Locating formal PA facilities in places with fewer public green resources and reducing the prevalence of takeaway stores in areas with formal PA resources may maximise the health benefits to be derived from these neighbourhood resources

Donor-acceptor dyads and triads employing core-substituted naphthalene diimides:a synthetic and spectro (electrochemical) study

Donor-acceptor dyads and triads comprising core-substituted naphthalene diimide (NDI) chromophores and either phenothiazine or phenoxazine donors are described. Synthesis combined with electrochemical and spectroelectrochemical investigations facilitates characterisation of the various redox states of these molecules, confirming the ability to combine arrays of electron donating and accepting moieties into single species that retain the redox properties of these individual moieties

Thionated perylene diimide–phenothiazine dyad: synthesis, structure, and electrochemical studies

Perylene diimides (PDIs) are promising candidates for n-type semiconductor materials and, thus, for use in organic electronics. Thionation of the imide moiety provides an efficient strategy to control the donor−acceptor gap of these types of compounds, although the degree and selectivity of thionation can be hard to achieve. Through the design of a sterically encumbered PDI−phenothiazine dyad, a previously unattained geminal thionation pattern has been realized, providing the first example of a perylene-monoimide-monothioimide. The electrochemical and solid-state structural properties of this uniquely thionated dyad are reported and compared to those of the nonthionated parent molecule. It is found that thionation enhances the electron affinity of the PDI core, affecting electrochemical and spectroelectochemcial behavior of the dyad without significantly affecting the solid-state packing of the molecules

Psychosocial work factors and social inequalities in psychological distress: a population-based study.

BACKGROUND: Mental health problems (MHP) are the leading cause of disability worldwide. The inverse association between socioeconomic position (SEP) and MHP has been well documented. There is prospective evidence that factors from the work environment, including adverse psychosocial work factors, could contribute to the development of MHP including psychological distress. However, the contribution of psychosocial work factors to social inequalities in MHP remains unclear. This study evaluates the contribution of psychosocial work factors from two highly supported models, the Demand-Control-Support (DCS) and the Effort-Reward Imbalance (ERI) models to SEP inequalities of psychological distress in men and women from a population-based sample of Quebec workers. METHODS: Data were collected during a survey on working conditions, health and safety at work. SEP was evaluated using education, occupation and household income. Psychosocial work factors and psychological distress were assessed using validated instruments. Mean differences (MD) in the score of psychological distress were estimated separately for men and women. RESULTS: Low education level and low household income were associated with psychological distress among men (MD, 0.56 (95% CI 0.06; 1.05) and 1.26 (95% CI 0.79; 1.73) respectively). In men, the contribution of psychosocial work factors from the DCS and the ERI models to the association between household income and psychological distress ranged from 9% to 24%. No clear inequalities were observed among women. CONCLUSIONS: These results suggest that psychosocial work factors from the DCS and the ERI models contribute to explain a part of social inequalities in psychological distress among men. Psychosocial factors at work are frequent and modifiable. The present study supports the relevance of targeting these factors for the primary prevention of MHP and for health policies aiming to reduce social inequalities in mental health

Prevalence and risk factors for chronic kidney disease of unknown cause in Malawi: a cross-sectional analysis in a rural and urban population.

BACKGROUND: An epidemic of chronic kidney disease of unknown cause (CKDu) is occurring in rural communities in tropical regions of low-and middle-income countries in South America and India. Little information is available from Southern African countries which have similar climatic and occupational characteristics to CKDu-endemic countries. We investigated whether CKDu is prevalent in Malawi and identified its potential risk factors in this setting. METHODS: We conducted a cross-sectional study from January-August 2018 collecting bio samples and anthropometric data in two Malawian populations. The sample comprised adults > 18 years (n = 821) without diabetes, hypertension, and proteinuria. Estimates of glomerular filtration rate (eGFR) were calculated using the CKD-EPI equation. Linear and logistic regression models were applied with potential risk factors, to estimate risk of reduced eGFR. RESULTS: The mean eGFR was 117.1 ± 16.0 ml/min per 1.73m2 and the mean participant age was 33.5 ± 12.7 years. The prevalence of eGFR< 60 was 0.2% (95% confidence interval (95% CI) 0.1, 0.9); the prevalence of eGFR< 90 was 5% (95% CI =3.2, 6.3). We observed a higher prevalence in the rural population (5% (3.6, 7.8)), versus urban (3% (1.4, 6.7)). Age and BMI were associated with reduced eGFR< 90 [Odds ratio (OR) (95%CI) =3.59 (2.58, 5.21) per ten-year increment]; [OR (95%CI) =2.01 (1.27, 3.43) per 5 kg/m2 increment] respectively. No increased risk of eGFR < 90 was observed for rural participants [OR (95%CI) =1.75 (0.50, 6.30)]. CONCLUSIONS: Reduced kidney function consistent with the definition of CKDu is not common in the areas of Malawi sampled, compared to that observed in other tropical or sub-tropical countries in Central America and South Asia. Reduced eGFR< 90 was related to age, BMI, and was more common in rural areas. These findings are important as they contradict some current hypothesis that CKDu is endemic across tropical and sub-tropical countries. This study has enabled standardized comparisons of impaired kidney function between and within tropical/subtropical regions of the world and will help form the basis for further etiological research, surveillance strategies, and the implementation and evaluation of interventions

Are environmental risk factors for current wheeze in the International Study of Asthma and Allergies in Childhood (ISAAC) phase three due to reverse causation?

BACKGROUND: Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC) measured the global prevalence of symptoms of asthma in children. We undertook comprehensive analyses addressing risk factors for asthma symptoms in combination, at both the individual and the school level, to explore the potential role of reverse causation due to selective avoidance or confounding by indication. OBJECTIVE: To explore the role of reverse causation in risk factors of asthma symptoms. METHODS: We compared two sets of multilevel logistic regression analyses, using (a) individual level exposure data and (b) school level average exposure (ie prevalence), in two different age groups. In individual level analyses, reverse causation is a possible concern if individual level exposure statuses were changed as a result of asthma symptoms or diagnosis. School level analyses may suffer from ecologic confounding, but reverse causation is less of a concern because individual changes in exposure status as a result of asthma symptoms would only have a small effect on overall school exposure levels. RESULTS: There were 131 924 children aged 6-7 years (2428 schools, 25 countries) with complete exposure, outcome and confounder data. The strongest associations in individual level analyses (fully adjusted) were for current paracetamol use (odds ratio = 2.06; 95% confidence interval 1.97-2.16), early life antibiotic use (1.65; 1.58-1.73) and open fire cooking (1.44; 1.26-1.65). In school level analyses, these risk factors again showed increased risks. There were 238 586 adolescents aged 13-14 years (2072 schools, 42 countries) with complete exposure, outcome and confounder data. The strongest associations in individual level analyses (fully adjusted) were for current paracetamol use (1.80; 1.75-1.86), cooking on an open fire (1.32; 1.22-1.43) and maternal tobacco use (1.23; 1.18-1.27). In school level analyses, these risk factors again showed increased risks. CONCLUSIONS & CLINICAL RELEVANCE: These analyses strengthen the potentially causal interpretation of previously reported individual level findings, by providing evidence against reverse causation

Harnessing the extracellular bacterial production of nanoscale cobalt ferrite with exploitable magnetic properties

Nanoscale ferrimagnetic particles have a diverse range of uses from directed cancer therapy and drug delivery systems to magnetic recording media and transducers. Such applications require the production of monodisperse nanoparticles with well-controlled size, composition, and magnetic properties. To fabricate these materials purely using synthetic methods is costly in both environmental and economical terms. However, metal-reducing microorganisms offer an untapped resource to produce these materials. Here, the Fe(III)-reducing bacterium Geobacter sulfurreducens is used to synthesize magnetic iron oxide nanoparticles. A combination of electron microscopy, soft X-ray spectroscopy, and magnetometry techniques was employed to show that this method of biosynthesis results in high yields of crystalline nanoparticles with a narrow size distribution and magnetic properties equal to the best chemically synthesized materials. In particular, it is demonstrated here that cobalt ferrite (CoFe2O4) nanoparticles with low temperature coercivity approaching 8 kOe and an effective anisotropy constant of ∼106 erg cm−3 can be manufactured through this biotechnological route. The dramatic enhancement in the magnetic properties of the nanoparticles by the introduction of high quantities of Co into the spinel structure represents a significant advance over previous biomineralization studies in this area using magnetotactic bacteria. The successful production of nanoparticulate ferrites achieved in this study at high yields could open up the way for the scaled-up industrial manufacture of nanoparticles using environmentally benign methodologies

Are environmental factors for atopic eczema in ISAAC Phase Three due to reverse causation?

Some previously described environmental associations for atopic eczema (AE) may be due to reverse causation. We explored the role of reverse causation by comparing individual- and school-level results for multiple AE risk factors. ISAAC Phase Three surveyed children within schools (the sampling unit) on AE symptoms and potential risk factors. We assessed the effect of these risk factors on AE symptoms using mixed-effect logistic regression models, first with individual-level exposure data and second with school-level exposure prevalence. 546,348 children from 53 countries were included. At age 6-7 the strongest individual-level associations were with current paracetamol use (odds ratio=1.45, 95% confidence interval 1.37-1.54), which persisted at school-level (1.55, 1.10-2.21), antibiotics (1.41, 1.34-1.48) and early life paracetamol use (1.28, 1.21-1.36) with the former persisting at school-level while the latter was no longer observed (1.35, 1.00-1.82 and 0.94, 0.69-1.28 respectively). At age 13-14 the strongest associations at individual-level were with current paracetamol use (1.57, 1.51-1.63) and open-fire cooking (1.46, 1.33-1.62); both were stronger at school-level (2.57, 1.84-3.59 and 2.38, 1.52-3.73 respectively). Association with exposure to heavy traffic (1.31, 1.27-1.36) also persisted at school-level (1.40, 1.07-1.82). Most individual- and school level effects were consistent tending to exclude reverse causation