102 research outputs found

    Human urinary mutagenicity after wood smoke exposure during traditional temazcal use.

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    In Central America, the traditional temazcales or wood-fired steam baths, commonly used by many Native American populations, are often heated by wood fires with little ventilation, and this use results in high wood smoke exposure. Urinary mutagenicity has been previously employed as a non-invasive biomarker of human exposure to combustion emissions. This study examined the urinary mutagenicity in 19 indigenous Mayan families from the highlands of Guatemala who regularly use temazcales (N = 32), as well as control (unexposed) individuals from the same population (N = 9). Urine samples collected before and after temazcal exposure were enzymatically deconjugated and extracted using solid-phase extraction. The creatinine-adjusted mutagenic potency of urine extracts was assessed using the plate-incorporation version of the Salmonella mutagenicity assay with strain YG1041 in the presence of exogenous metabolic activation. The post-exposure mutagenic potency of urine extracts were, on average, 1.7-fold higher than pre-exposure samples (P < 0.005) and also significantly more mutagenic than the control samples (P < 0.05). Exhaled carbon monoxide (CO) was ~10 times higher following temazcal use (P < 0.0001), and both CO level and time spent in temazcal were positively associated with urinary mutagenic potency (i.e. P < 0.0001 and P = 0.01, respectively). Thus, the wood smoke exposure associated with temazcal use contributes to increased excretion of conjugated mutagenic metabolites. Moreover, urinary mutagenic potency is correlated with other metrics of exposure (i.e. exhaled CO, duration of exposure). Since urinary mutagenicity is a biomarker associated with genetic damage, temazcal use may therefore be expected to contribute to an increased risk of DNA damage and mutation, effects associated with the initiation of cancer

    Extreme Dysbiosis of the Microbiome in Critical Illness.

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    Critical illness is hypothesized to associate with loss of "health-promoting" commensal microbes and overgrowth of pathogenic bacteria (dysbiosis). This dysbiosis is believed to increase susceptibility to nosocomial infections, sepsis, and organ failure. A trial with prospective monitoring of the intensive care unit (ICU) patient microbiome using culture-independent techniques to confirm and characterize this dysbiosis is thus urgently needed. Characterizing ICU patient microbiome changes may provide first steps toward the development of diagnostic and therapeutic interventions using microbiome signatures. To characterize the ICU patient microbiome, we collected fecal, oral, and skin samples from 115 mixed ICU patients across four centers in the United States and Canada. Samples were collected at two time points: within 48 h of ICU admission, and at ICU discharge or on ICU day 10. Sample collection and processing were performed according to Earth Microbiome Project protocols. We applied SourceTracker to assess the source composition of ICU patient samples by using Qiita, including samples from the American Gut Project (AGP), mammalian corpse decomposition samples, childhood (Global Gut study), and house surfaces. Our results demonstrate that critical illness leads to significant and rapid dysbiosis. Many taxons significantly depleted from ICU patients versus AGP healthy controls are key "health-promoting" organisms, and overgrowth of known pathogens was frequent. Source compositions of ICU patient samples are largely uncharacteristic of the expected community type. Between time points and within a patient, the source composition changed dramatically. Our initial results show great promise for microbiome signatures as diagnostic markers and guides to therapeutic interventions in the ICU to repopulate the normal, "health-promoting" microbiome and thereby improve patient outcomes. IMPORTANCE Critical illness may be associated with the loss of normal, "health promoting" bacteria, allowing overgrowth of disease-promoting pathogenic bacteria (dysbiosis), which, in turn, makes patients susceptible to hospital-acquired infections, sepsis, and organ failure. This has significant world health implications, because sepsis is becoming a leading cause of death worldwide, and hospital-acquired infections contribute to significant illness and increased costs. Thus, a trial that monitors the ICU patient microbiome to confirm and characterize this hypothesis is urgently needed. Our study analyzed the microbiomes of 115 critically ill subjects and demonstrated rapid dysbiosis from unexpected environmental sources after ICU admission. These data may provide the first steps toward defining targeted therapies that correct potentially "illness-promoting" dysbiosis with probiotics or with targeted, multimicrobe synthetic "stool pills" that restore a healthy microbiome in the ICU setting to improve patient outcomes

    Tissue-specific in vivo genetic toxicity of nine polycyclic aromatic hydrocarbons assessed using the Muta™Mouse transgenic rodent assay

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    Test batteries to screen chemicals for mutagenic hazard include several endpoints regarded as effective for detecting genotoxic carcinogens. Traditional in vivo methods primarily examine clastogenic endpoints in haematopoietic tissues. Although this approach is effective for identifying systemically distributed clastogens, some mutagens may not induce clastogenic effects; moreover, genotoxic effects may be restricted to the site of contact and/or related tissues. An OECD test guideline for transgenic rodent (TGR) gene mutation assays was released in 2011, and the TGR assays permit assessment of mutagenicity in any tissue. This study assessed the responses of two genotoxicity endpoints following sub-chronic oral exposures of male Muta™Mouse to 9 carcinogenic polycyclic aromatic hydrocarbons (PAHs). Clastogenicity was assessed via induction of micronuclei in peripheral blood, and mutagenicity via induction of lacZ transgene mutations in bone marrow, glandular stomach, small intestine, liver, and lung. Additionally, the presence of bulky PAH-DNA adducts was examined. Five of the 9 PAHs elicited positive results across all endpoints in at least one tissue, and no PAHs were negative or equivocal across all endpoints. All PAHs were positive for lacZ mutations in at least one tissue (sensitivity = 100%), and for 8 PAHs, one or more initial sites of chemical contact (i.e., glandular stomach, liver, small intestine) yielded a greater response than bone marrow. Five PAHs were positive in the micronucleus assay (sensitivity = 56%). Furthermore, all PAHs produced DNA adducts in at least one tissue. The results demonstrate the utility of the TGR assay for mutagenicity assessment, especially for compounds that may not be systemically distributed.</p

    Influence of Physical Activity Participation on the Associations between Eating Behaviour Traits and Body Mass Index in Healthy Postmenopausal Women

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    Available data reveals inconsistent relationships between eating behaviour traits and markers of adiposity level. It is thus relevant to investigate whether other factors also need to be considered when interpreting the relationship between eating behaviour traits and adiposity. The objective of this cross-sectional study was thus to examine whether the associations between variables of the Three-Factor Eating Questionnaire (TFEQ) and adiposity are influenced by the level of physical activity participation. Information from the TFEQ and physical activity was obtained from 113 postmenopausal women (56.7 ± 4.2 years; 28.5 ± 5.9 kg/m2). BMI was compared between four groups formed on the basis of the physical activity participation and eating behaviour traits medians. In groups of women with higher physical activity participation, BMI was significantly lower in women who presented higher dietary restraint when compared to women who had lower dietary restraint (25.5 ± 0.5 versus 30.3 ± 1.7 kg/m2, P < .05). In addition, among women with lower physical activity participation, BMI was significantly lower in women presenting a lower external hunger than in those with a higher external hunger (27.5 ± 0.8 versus 32.4 ± 1.1 kg/m2, P < .001). Our results suggest that physical activity participation should also be taken into account when interpreting the relationship between adiposity and eating behaviour traits

    Simultaneous Measurement of Benzo[a]pyrene-induced Pig-a and lacZ Mutations, Micronuclei and DNA Adducts in Muta™ Mouse

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    In this study we compared the response of the Pig-a gene mutation assay to that of the lacZ transgenic rodent mutation assay, and demonstrated that multiple endpoints can be measured in a 28-day repeat dose study. Muta™Mouse were dosed daily for 28 days with benzo[a]pyrene (BaP; 0, 25, 50 and 75 mg/kg body weight/day) by oral gavage. Micronucleus (MN) frequency was determined in reticulocytes (RETs) 48 hr following the last dose. 72 h following the last dose, mice were euthanized, and tissues (glandular stomach, small intestine, bone marrow and liver) were collected for lacZ mutation and DNA adduct analysis, and blood was evaluated for Pig-a mutants. BaP-derived DNA adducts were detected in all tissues examined and significant dose-dependent increases in mutant Pig-a phenotypes (i.e., RETCD24- and RBC CD24-) and lacZ mutants were observed. We estimate that mutagenic efficiency (i.e., rate of conversion of adducts into mutations) was much lower for Pig-a compared to lacZ, and speculate that this difference is likely explained by differences in repair capacity between the gene targets, and differences in the cell populations sampled for Pig-a versus lacZ. The BaP doubling doses for both gene targets, however, were comparable, suggesting that similar mechanisms are involved in the accumulation of gene mutations. Significant dose-related increases in % MN were also observed; however, the doubling dose was considerably higher for this endpoint. The similarity in dose response kinetics of Pig-a and lacZ provides further evidence for the mutational origin of glycosylphosphatidylinositol (GPI)-anchor deficiencies detected in the Pig-a assay. Environ. Mol. Mutagen. 2011. © 2011 Wiley-Liss, Inc

    Association entre la fréquence de consultation des médias d’information et la détresse psychologique chez les femmes enceintes durant la pandémie de COVID-19

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    OBJECTIVE: Examine the association between news media use frequency during the COVID-19 pandemic and the scale of psychological distress in pregnant women, considering this distress known harmful effects on the fetus development. METHOD: Pregnant women living in Quebec province (N = 1014) have been recruited in April 2020 through social media, while a state of health emergency was declared. Participants were divided in 4 groups, according to self-reported frequency of news media consulting (little or none; one time a day; several times a day; constant). They filled measures of depressive symptoms, negative affects, post-traumatic stress symptoms and anxiety specific to COVID-19. Instrument scores were grouped under a unique factor of psychological distress. RESULTS: An ANCOVA controlling for age, gestational age, education level, household annual revenue and a diagnosed mental disorder present at the time of participation in study shows that news media exposure frequency is significantly associated with psychological distress severity in pregnant women, during COVID-19 pandemic, F(3,998) = 27.02, p < 0.001, η2 partial = 0.08. Given the mean comparisons a posteriori, higher psychological distress rates are found as soon as news media exposure exceeds once a day (effect sizes between 0.38 and 0.81). CONCLUSIONS: The more pregnant women report consulting the news media during the COVID-19 pandemic, the more likely they are to exhibit psychological distress. Results provide one of the first empirical supports to recommendations of World Health Organization, Canada government and psychiatric associations that encourage population to limit their news media consulting during the COVID-19 pandemic

    Uptrend in distress and psychiatric symptomatology in pregnant women during the coronavirus disease 2019 pandemic

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    Introduction: Prenatal maternal distress has a negative impact on the course of pregnancy, fetal development, offspring development, and later psychopathologies. The study aimed to determine the extent to which the coronavirus disease 2019 (COVID-19) pandemic may aggravate the prenatal distress and psychiatric symptomatology of pregnant women. Material and methods: Two cohorts of pregnant volunteer women were evaluated, one that was recruited before the COVID-19 pandemic (n = 496) through advertisements in prenatal clinics in Quebec, Canada, from April 2018 to March 2020; the other (n = 1258) was recruited online during the pandemic from 2 April to 13 April 2020. Prenatal distress and psychiatric symptomatology were measured with the Kessler Distress Scale (K10), Post-traumatic Checklist for DSM-5 (PCL-5), Dissociative Experiences Scale (DES-II), and Positive and Negative Affect Schedule (PANAS). Results: The 1754 pregnant women (Mage = 29.27, SD = 4.23) were between 4 and 41 gestational weeks (M = 24.80, SD = 9.42), were generally educated (91.3% had post-high-school training), and financially well-resourced (85.3% were above the low-income cut-off). A multivariate analysis of covariance controlling for age, gestational age, household income, education, and lifetime psychiatric disorders showed a large effect size (ES) in the difference between the two cohorts on psychiatric symptoms (Wilks’ λ = 0.68, F6,1400 = 108.50, P &lt;.001, partial η2 = 0.32). According to post-hoc analyses of covariance, the COVID-19 women reported higher levels of depressive and anxiety symptoms (ES = 0.57), dissociative symptoms (ES = 0.22 and ES = 0.25), symptoms of post-traumatic stress disorder (ES = 0.19), and negative affectivity (ES = 0.96), and less positive affectivity (ES = 0.95) than the pre-COVID-19 cohort. Women from the COVID-19 cohort were more likely than pre-COVID-19 women to present clinically significant levels of depressive and anxiety symptoms (OR = 1.94, χ2[1] = 10.05, P =.002). Multiple regression analyses indicated that pregnant women in the COVID-19 cohort having a previous psychiatric diagnosis or low income would be more prone to elevated distress and psychiatric symptoms. Conclusions: Pregnant women assessed during the COVID-19 pandemic reported more distress and psychiatric symptoms than pregnant women assessed before the pandemic, mainly in the form of depression and anxiety symptoms. Given the harmful consequences of prenatal distress on mothers and offspring, the presently observed upsurge of symptoms in pregnant women calls for special means of clinical surveillance. © 2020 Nordic Federation of Societies of Obstetrics and Gynecolog
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