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Combining different assays and chemical analysis to characterize the genotoxicity of waters impacted by textile discharges 下载免费PDF全文
Francine I. Vacchi Josiane A. S. Vendemiatti Vanessa Brosselin Bianca Ferreira da Silva Maria Valnice B. Zanoni Michel DeMeo Sylvie Bony Alain Devaux Gisela A. Umbuzeiro 《Environmental and molecular mutagenesis》2016,57(7):559-571
Waters receiving textile discharges can exhibit genotoxic and mutagenic activity, which has been related to the presence of dyes and aromatic amines as synthesis precursors or byproducts. The aim of this study was to identify dyes and aromatic amines in water samples impacted by textile discharges, and to evaluate the genotoxic responses of these samples using the Salmonella/microsome assay in strains TA98 and YG1041, and the Fpg‐modified comet assay in the RTL‐W1 fish cell line. The genotoxicity of river samples downstream of the discharge was greater than the upstream samples in both of the Ames tests. The Fpg‐modified comet assay detected similar levels of DNA damage in the upstream and downstream samples. Mutagenicity was not detected with TA98, except for the Quilombo River samples, but when YG1041 was used as the tester strain mutagenicity was detected for all sites with a very different profile in upstream sites relative to the other sites. The mutagenic response strongly indicated that aromatic amines or dyes were contributing to the mutagenic activity downstream. The impact of textile discharges was also confirmed by chemical analysis, because the highest concentrations of azo dyes and aromatic amines were detected in the river downstream. This study shows the value of combining assays measuring complementary endpoints to better characterize the mutagenicity of environmental samples, with the advantage that this approach provides an indication of what classes of compounds are responsible for the effect. Environ. Mol. Mutagen. 57:559–571, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
234.
Sandrine Lemoine René Rouet Alain Manrique Jean‐Luc Hanouz 《Fundamental & clinical pharmacology》2014,28(5):481-488
Lipid emulsions are used in the reversal of local anesthetic toxicity. The aim of this study was to investigate the cellular electrophysiological effects of long‐chain triglyceride lipid emulsion (LCTE) on cardiac action potential characteristics and conduction disturbances induced by bupivacaine. Purkinje fibers were dissected from the left ventricle of New Zealand white rabbit hearts and superfused with either Tyrode's solution during 30 min (control group), with bupivacaine 10?6 m , 10?5 m , and 5.10?5 m alone, or in the presence of LCTE 0.5%, in addition, LCTE at 0.1%, 0.5%, and 1% was perfused alone. Electrophysiological parameters were recorded using the conventional microelectrode technique (37 °C, 1 Hz frequency). Bupivacaine 5.10?5 m ‐induced conduction blocks (8/8 preparations): LCTE 0.5% suppressed the bupivacaine 5.10?5 m ‐induced conduction blocks (1/8 preparations). Exposure to bupivacaine 10?6 m , 10?5 m , and 5.10?5 m resulted in a significant decrease in the maximal rate of depolarization (Vmax) (respectively, 25%, 55%, 75%; P < 0.002 vs. control group). In the presence of LCTE 0.5%, bupivacaine 10?6 m did not significantly decreased Vmax (13%; P = 0.10 vs. control group). The decrease in Vmax resulting from bupivacaine 10?5 m alone was significantly less in the presence of LCTE 0.5% (P < 0.01 vs. bupivacaine 10?5 m alone). Exposure to bupivacaine 10?6 m , 10?5 m , and 5.10?5 m alone or in the presence of LCTE 0.5% resulted in a significant decrease in action potential duration measured at 50% and 90% repolarization (APD50 and APD90; P < 0.01 vs. control group). LCTE inhibited the Purkinje fibers conduction blocks induced by bupivacaine. Moreover, LCTE 0.5% attenuates the decrease in Vmax induced by bupivacaine 10?6 m and 10?5 m . 相似文献
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Olga Sakwinska Viktoria Bastic Schmid Bernard Berger Anne Bruttin Kristina Keitel Mélissa Lepage Deborah Moine Catherine Ngom Bru Harald Brüssow Alain Gervaix 《Journal of clinical microbiology》2014,52(5):1590-1594
Our study is the first to compare the nasopharyngeal microbiota of pediatric pneumonia patients and control children by 454 pyrosequencing. A distinct microbiota was associated with different pneumonia etiologies. Viral pneumonia was associated with a high abundance of the operational taxonomic unit (OTU) corresponding to Moraxella lacunata. Patients with nonviral pneumonia showed high abundances of OTUs of three typical bacterial pathogens, Streptococcus pneumoniae complex, Haemophilus influenzae complex, and Moraxella catarrhalis. Patients classified as having no definitive etiology harbored microbiota particularly enriched in the H. influenzae complex. We did not observe a commensal taxon specifically associated with health. The microbiota of the healthy nasopharynx was more diverse and contained a wider range of less abundant taxa. 相似文献
236.
Federico F. Trigo Takeshi Sakaba David Ogden Alain Marty 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(44):18138-18143
To distinguish between different models of vesicular release in brain synapses, it is necessary to know the number of vesicles of transmitter that can be released immediately at individual synapses by a high-calcium stimulus, the readily releasable pool (RRP). We used direct stimulation by calcium uncaging at identified, single-site inhibitory synapses to investigate the statistics of vesicular release and the size of the RRP. Vesicular release, detected as quantal responses in the postsynaptic neuron, showed an unexpected stochastic variation in the number of quanta from stimulus to stimulus at high intracellular calcium, with a mean of 1.9 per stimulus and a maximum of three or four. The results provide direct measurement of the RRP at single synaptic sites. They are consistent with models in which release proceeds from a small number of vesicle docking sites with an average occupancy around 0.7. 相似文献
237.
Amphetamine-Induced Dopamine Release and Neurocognitive Function in Treatment-Naive Adults with ADHD
Mariya V Cherkasova Nazlie Faridi Kevin F Casey Gillian A O'Driscoll Lily Hechtman Ridha Joober Glen B Baker Jennifer Palmer Alain Dagher Marco Leyton Chawki Benkelfat 《Neuropsychopharmacology》2014,39(6):1498-1507
Converging evidence from clinical, preclinical, neuroimaging, and genetic research implicates dopamine neurotransmission in the pathophysiology of attention deficit hyperactivity disorder (ADHD). The in vivo neuroreceptor imaging evidence also suggests alterations in the dopamine system in ADHD; however, the nature and behavioral significance of those have not yet been established. Here, we investigated striatal dopaminergic function in ADHD using [11C]raclopride PET with a d-amphetamine challenge. We also examined the relationship of striatal dopamine responses to ADHD symptoms and neurocognitive function. A total of 15 treatment-free, noncomorbid adult males with ADHD (age: 29.87±8.65) and 18 healthy male controls (age: 25.44±6.77) underwent two PET scans: one following a lactose placebo and the other following d-amphetamine (0.3 mg/kg, p.o.), administered double blind and in random order counterbalanced across groups. In a separate session without a drug, participants performed a battery of neurocognitive tests. Relative to the healthy controls, the ADHD patients, as a group, showed greater d-amphetamine-induced decreases in striatal [11C]raclopride binding and performed more poorly on measures of response inhibition. Across groups, a greater magnitude of d-amphetamine-induced change in [11C]raclopride binding potential was associated with poorer performance on measures of response inhibition and ADHD symptoms. Our findings suggest an augmented striatal dopaminergic response in treatment-naive ADHD. Though in contrast to results of a previous study, this finding appears consistent with a model proposing exaggerated phasic dopamine release in ADHD. A susceptibility to increased phasic dopamine responsivity may contribute to such characteristics of ADHD as poor inhibition and impulsivity. 相似文献
238.
Jorge Csar Correia Hafsa Meraj Soo Huat Teoh Ahmed Waqas Maaz Ahmad Luis Velez Lapo Zoltan Pataky Alain Golay 《Bulletin of the World Health Organization》2021,99(3):209
ObjectiveTo determine the effectiveness of telemedicine in the delivery of diabetes care in low- and middle-income countries.MethodsWe searched seven databases up to July 2020 for randomized controlled trials investigating the effectiveness of telemedicine in the delivery of diabetes care in low- and middle-income countries. We extracted data on the study characteristics, primary end-points and effect sizes of outcomes. Using random effects analyses, we ran a series of meta-analyses for both biochemical outcomes and related patient properties.FindingsWe included 31 interventions in our meta-analysis. We observed significant standardized mean differences of −0.38 for glycated haemoglobin (95% confidence interval, CI: −0.52 to −0.23; I2 = 86.70%), −0.20 for fasting blood sugar (95% CI: −0.32 to −0.08; I2 = 64.28%), 0.81 for adherence to treatment (95% CI: 0.19 to 1.42; I2 = 93.75%), 0.55 for diabetes knowledge (95% CI: −0.10 to 1.20; I2 = 92.65%) and 1.68 for self-efficacy (95% CI: 1.06 to 2.30; I2 = 97.15%). We observed no significant treatment effects for other outcomes, with standardized mean differences of −0.04 for body mass index (95% CI: −0.13 to 0.05; I2 = 35.94%), −0.06 for total cholesterol (95% CI: −0.16 to 0.04; I2 = 59.93%) and −0.02 for triglycerides (95% CI: −0.12 to 0.09; I2 = 0%). Interventions via telephone and short message service yielded the highest treatment effects compared with services based on telemetry and smartphone applications.ConclusionAlthough we determined that telemedicine is effective in improving several diabetes-related outcomes, the certainty of evidence was very low due to substantial heterogeneity and risk of bias. 相似文献
239.
Brandon S. Allport Sara Johnson Anushka Aqil Alain B. Labrique Timothy Nelson Angela KC Yorghos Carabas Arik V. Marcell 《Academic pediatrics》2018,18(7):746-753
Paternal involvement in children's lives is associated with a variety of child outcomes, including improved cognition, improved mental health, reduced obesity rates, and asthma exacerbation. Given this evidence, the American Academy of Pediatrics has promoted actions by pediatricians to engage fathers in pediatric care. Despite these recommendations, the mother–child dyad, rather than the mother–father–child triad, remains a frequent focus of care. Furthermore, pediatric care is often leveraged to improve maternal health, such as screening for maternal depression, but paternal health is infrequently addressed even as men tend to exhibit riskier behaviors, poorer primary care utilization, and lower life expectancy. Therefore, increasing efforts by pediatric clinicians to engage fathers may affect the health of both father and child. These efforts to engage fathers are informed by currently used definitions and measures of father involvement, which are discussed here. Factors described in the literature that affect father involvement are also summarized, including culture and context; interpersonal factors; logistics; knowledge and self-efficacy; and attitudes, beliefs, and incentives. Innovative ways to reach fathers both in the clinic and in other settings are currently under investigation, including use of behavior change models, motivational interviewing, mobile technologies, peer support groups, and policy advocacy efforts. These modalities show promise in effectively engaging fathers and improving family health. 相似文献
240.