Browsing by Author "Douwes J"

Now showing 1 - 8 of 8
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    A perspective on green, blue, and grey spaces, biodiversity, microbiota, and human health.
    (Elsevier B.V., 2023-09-20) Potter JD; Brooks C; Donovan G; Cunningham C; Douwes J
    Humans have lived from equator to poles for millennia but are now increasingly intruding into the wild spaces of other species and steadily extruding ourselves from our own wild spaces, with a profound impact on: our relationship with the natural world; survival of other species; pollution; climate change; etc. We have yet to grasp how these changes directly impact our own health. The primary focus of this paper is on the beneficial influence of proximity to the natural environment. We summarize the evidence for associations between exposure to green space and blue space and improvements in health. In contrast, grey space - the urban landscape - largely presents hazards as well as reducing exposure to green and blue space and isolating us from the natural environment. We discuss various hypotheses that might explain why green, blue, and grey space affect health and focus particularly on the importance of the biodiversity hypothesis and the role of microbiota. We discuss possible mechanisms and exposure routes - air, soil, and water. We highlight the problem of exposure assessment, noting that many of our current tools are not fit for the purpose of understanding exposure to green and blue space, aerosols, soils, and water. We briefly discuss possible differences between indigenous perspectives on the nature of our relationship with the environment and the more dominant international-science view. Finally, we present research gaps and discuss future directions, particularly focusing on the ways in which we might - even in the absence of a full understanding of the mechanisms by which blue, green, and grey space affect our health - begin to implement policies to restore some balance to our environment of with the aim of reducing the large global burden of ill health.
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    Green space and stroke: A scoping review of the evidence.
    (Elsevier B.V, 2024-02-15) Whyte M; Douwes J; Ranta A
    BACKGROUND: Global industrialisation and urbanisation has led to an increased interest in the link between the environment and health. Stroke is a major cause of morbidity and mortality, and there is increased evidence that environmental factors may affect both the incidence and severity of stroke. This review summarises the evidence for relationship between green space exposure and stroke incidence and outcomes. METHODS: We conducted a literature search in Medline and Scopus until 1 August 2023, and screened references of relevant articles. Selected articles were appraised for their relevance, and critically reviewed. The findings were thematically categorised. RESULTS: Of the 1342 papers identified, 27 were included. These involved a mix of study designs (cohort, cross-sectional, quasi-experimental, time stratified case crossover and ecological). There was consistent evidence indicating a protective association between green space exposure and disability and stroke-related death with mortality hazard ratios between 0.66 and 0.95. Most studies also showed that green space was inversely associated with stroke risk, with risk estimates from studies showing a protective effect ranging between 0.4 and 0.98; however, results were more mixed and some did not reach statistical significance. The moderating effects of green spaces on ambient temperatures, noise and air pollution, and psychosocial health plus greater enjoyment and opportunity for exercise and enrichment of the human microbiome may underly these associations. CONCLUSION: There is likely some protective effect of green space on stroke, with the benefits most convincingly shown for post-stroke outcomes. More research is recommended to confirm the protective association between green space exposure and reduced stroke risk.
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    Gut microbiome signature and nasal lavage inflammatory markers in young people with asthma
    (Elsevier Inc on behalf of the American Academy of Allergy, Asthma & Immunology (AAAAI), 2024-05) Sampaio Dotto Fiuza B; Machado de Andrade C; Meirelles PM; Santos da Silva J; de Jesus Silva M; Vila Nova Santana C; Pimentel Pinheiro G; Mpairwe H; Cooper P; Brooks C; Pembrey L; Taylor S; Douwes J; Cruz ÁA; Barreto ML; Pearce N; Figueiredo CAV
    BACKGROUND: Asthma is a complex disease and a severe global public health problem resulting from interactions between genetic background and environmental exposures. It has been suggested that gut microbiota may be related to asthma development; however, such relationships needs further investigation. OBJECTIVE: This study aimed to characterize the gut microbiota as well as the nasal lavage cytokine profile of asthmatic and nonasthmatic individuals. METHODS: Stool and nasal lavage samples were collected from 29 children and adolescents with type 2 asthma and 28 children without asthma in Brazil. Amplicon sequencing of the stool bacterial V4 region of the 16S rRNA gene was performed using Illumina MiSeq. Microbiota analysis was performed by QIIME 2 and PICRUSt2. Type 2 asthma phenotype was characterized by high sputum eosinophil counts and positive skin prick tests for house dust mite, cockroach, and/or cat or dog dander. The nasal immune marker profile was assessed using a customized multiplex panel. RESULTS: Stool microbiota differed significantly between asthmatic and nonasthmatic participants (P = .001). Bacteroides was more abundant in participants with asthma (P < .05), while Prevotella was more abundant in nonasthmatic individuals (P < .05). In people with asthma, the relative abundance of Bacteroides correlated with IL-4 concentration in nasal lavage samples. Inference of microbiota functional capacity identified differential fatty acid biosynthesis in asthmatic compared to nonasthmatic subjects. CONCLUSION: The stool microbiota differed between asthmatic and nonasthmatic young people in Brazil. Asthma was associated with higher Bacteroides levels, which correlated with nasal IL-4 concentration.
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    Nitrate in drinking water and pregnancy outcomes: A narrative review of epidemiological evidence and proposed biological mechanisms
    (PLOS, 2024-01-17) Royal H; Mannetje A; Hales S; Douwes J; Berry M; Chambers T; Schullehner J
    There is emerging evidence of an association between nitrate contamination in drinking water and adverse pregnancy outcomes. Few studies have discussed the evidence in the context of plausible biological mechanisms. We performed a narrative review of the current evidence investigating associations between nitrate in drinking water and the risk of adverse pregnancy outcomes with a focus on congenital anomalies (CA) and preterm birth (PTB). We also reviewed evidence and discuss several biological mechanisms that may explain the observed associations. We reviewed cohort and case-control epidemiological studies assessing associations between maternal nitrate exposure and adverse pregnancy outcomes published until January 2023. Three plausible mechanisms may explain how maternal exposure to nitrate may impact pregnancy outcomes, which include the formation of Nnitroso compounds (NOC), thyroid dysfunction and oxidative stress. For CA, seven studies were included (two cohort and five case-control studies). The strongest associations observed in epidemiological studies were for neural tube defects. Inconsistent positive and negative associations were observed for anomalies of the limb, eye, ear, face and neck. Of the four PTB studies (all cohort studies), three of the largest cohort studies observed associations between PTB with nitrate levels >5 mg/L while one small cohort study did not. Emerging epidemiological evidence has observed a potential increased risk of adverse pregnancy outcomes with elevated maternal nitrate exposure in drinking water. There are also plausible biological mechanisms to support this association. However, the current evidence lacks homogeneity and additional longitudinal evidence with robust exposure asssessments is required. Given the increasing concentrations of nitrate contamination in drinking water in many countries, and the adverse effects observed at concentrations below the current regulatory standard, a further precautionary approach should be adopted until futher evidence emerges.
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    The fecal microbiotas of women of Pacific and New Zealand European ethnicities are characterized by distinctive enterotypes that reflect dietary intakes and fecal water content.
    (Taylor and Francis Groups, 2023-02-17) Renall N; Lawley B; Vatanen T; Merz B; Douwes J; Corbin M; Te Morenga L; Kruger R; Breier BH; Tannock GW
    Obesity is a complex, multifactorial condition that is an important risk factor for noncommunicable diseases including cardiovascular disease and type 2 diabetes. While prevention and management require a healthy and energy balanced diet and adequate physical activity, the taxonomic composition and functional attributes of the colonic microbiota may have a supplementary role in the development of obesity. The taxonomic composition and metabolic capacity of the fecal microbiota of 286 women, resident in Auckland New Zealand, was determined by metagenomic analysis. Associations with BMI (obese, nonobese), body fat composition, and ethnicity (Pacific, n = 125; NZ European women [NZE], n = 161) were assessed using regression analyses. The fecal microbiotas were characterized by the presence of three distinctive enterotypes, with enterotype 1 represented in both Pacific and NZE women (39 and 61%, respectively), enterotype 2 mainly in Pacific women (84 and 16%) and enterotype 3 mainly in NZE women (13 and 87%). Enterotype 1 was characterized mainly by the relative abundances of butyrate producing species, Eubacterium rectale and Faecalibacterium prausnitzii, enterotype 2 by the relative abundances of lactic acid producing species, Bifidobacterium adolescentis, Bifidobacterium bifidum, and Lactobacillus ruminis, and enterotype 3 by the relative abundances of Subdoligranulum sp., Akkermansia muciniphila, Ruminococcus bromii, and Methanobrevibacter smithii. Enterotypes were also associated with BMI, visceral fat %, and blood cholesterol. Habitual food group intake was estimated using a 5 day nonconsecutive estimated food record and a 30 day, 220 item semi-quantitative Food Frequency Questionnaire. Higher intake of 'egg' and 'dairy' products was associated with enterotype 3, whereas 'non-starchy vegetables', 'nuts and seeds' and 'plant-based fats' were positively associated with enterotype 1. In contrast, these same food groups were inversely associated with enterotype 2. Fecal water content, as a proxy for stool consistency/colonic transit time, was associated with microbiota taxonomic composition and gene pools reflective of particular bacterial biochemical pathways. The fecal microbiotas of women of Pacific and New Zealand European ethnicities are characterized by distinctive enterotypes, most likely due to differential dietary intake and fecal consistency/colonic transit time. These parameters need to be considered in future analyses of human fecal microbiotas.
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    Time trends in positive gonorrhoea diagnoses at the Christchurch Sexual Health Service (2012-2022): a data audit study.
    (CSIRO Publishing, 2024-06-27) Denison HJ; Creighton J; Douwes J; Coshall M; Young H; Tang W
    Background Gonorrhoea infections and antimicrobial resistance are rising in many countries, particularly among men who have sex with men, and an increasing proportion of infection is detected at extragenital sites. This study assessed trends in gonorrhoea diagnoses and antibiotic resistance at a sexual health service in New Zealand that followed national guidelines for specimen collection. Methods Routinely-collected data from Canterbury Health Laboratories of specimens taken at the Christchurch Sexual Health Service 2012–2022 were audited. Descriptive results included the number of patient testing events positive for gonorrhoea per year and site of infection (extragenital/urogenital). Annual test-positivity was calculated (number of positive patient testing events divided by total number of testing events) and the Cochran-Armitage Test for Trend was used to assess whether there was an association between test-positivity and year. Results Of 52,789 patient testing events, 1467 (2.8%) were positive for gonorrhoea (81% male). Half (49.3%) of people (57.9% of males, 12.2% of females) with a gonorrhoea infection had an extragenital infection in the absence of a urogenital infection. The number of extragenital infections increased at a faster rate than urogenital among males. Test-positivity increased from 1.3% in 2012 to 5.8% in 2022 (P < 0.001). Antimicrobial resistance was identified in many isolates. Ciprofloxacin resistance was high, but there were no cases of ceftriaxone resistance. Conclusions This study highlights the importance of extragenital sampling and maintaining bacterial culture methods for accurate diagnosis and treatment. The observation that gonorrhoea positivity rate and antimicrobial resistance rates are rising in New Zealand calls for urgent action.
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    "We don't really do doctors." messages from people diagnosed with occupational leptospirosis for medical professionals on infection, hospitalisation, and long-term effects.
    (Elsevier B.V., 2023-09) Prinsen G; Baker M; Benschop J; Collins-Emerson J; Douwes J; Fayaz A; Littlejohn S; Nisa S; Quin T; Yeung P
    Leptospirosis is largely an occupational disease for people working with livestock in Aotearoa New Zealand. Introduction of livestock vaccination and use of personal protective equipment has been associated with a reduction in the incidence. However, the incidence of occupational leptospirosis remains high, with significant burdens for affected families and healthcare system. For this article, a subset of thirteen participants from a nationwide leptospirosis case-control study (2019-2021) who were diagnosed with leptospirosis and worked with livestock at the time of illness were invited and agreed to a semi-structured interview. Interviewees reflected on their experiences as messages for medical professionals. The analysis of transcripts reveals widely shared experiences with infection, hospitalisation, and treatment, as well as long-term effects and recovery. Conclusions for medical professionals include that ill workers continue to have their diagnosis of leptospirosis delayed. This delay may contribute to more than half the people ill with leptospirosis hospitalised. Further, medical professionals' communication and relationship with ill people strongly colours the latter's experience, for good or for bad. Moreover, most interviewees experienced a recovery process that took several months of feeling tired, which undermined professional performance and emotional wellbeing.
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    Why has epidemiology not (yet) succeeded in identifying the origin of the asthma epidemic?
    (Oxford University Press, 2023-04-02) Antó JM; Pearce N; Douwes J; Garcia-Aymerich J; Pembrey L; Richiardi L; Sunyer J