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41.
Combining different assays and chemical analysis to characterize the genotoxicity of waters impacted by textile discharges
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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
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Leonardo Martinez Gisela Collazo Lilia Cabrera Antonio Bernabe-Ortiz Yasnina Ramos-Pe?a Richard Oberhelman 《The American journal of tropical medicine and hygiene》2013,89(2):229-231
Free-ranging chickens are often found in periurban communities in developing countries, and their feces can pose a significant public health sanitation problem. Corralling chickens raised in these periurban areas in chicken coops has been proposed previously as an intervention to address this problem. Aims of this study were to revisit households in a corralling intervention study conducted in 2000–2001 to compare poultry-raising practices and investigate current attitudes regarding the impact of raising chickens in a periurban environment. Sociobehavioral questionnaires were given sequentially to all study participants; 30 families (58%) ceased raising poultry of any kind, whereas 42 (81%) do not raise chickens in their home. This finding indicates a significant reduction in poultry-raising in our study population since 2000–2001, possibly because of acculturation and/or change in socioeconomic status. However, attitudes about corral use for raising poultry were overwhelmingly positive, and the most common reason cited was cleanliness of the home. 相似文献
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OBJECTIVE: Two simulation models were developed to analyze the cost-effectiveness of new treatments that affect the progression of rheumatoid arthritis (RA). METHODS: We used data from 2 cohorts of patients with early RA who had been followed up since disease onset (up to 15 years). In the Swedish study, 183 patients were followed up for a mean of 11.3 years. In the UK study, 916 patients were followed up for a mean of 7.8 years. Disease progression over 10 years was modeled as annual transitions between disease states, defined by Health Assessment Questionnaire (HAQ) scores. A regression model was used to estimate transition probabilities conditional on age, sex, and time since onset of disease, in order to allow simulation of different patient cohorts. Costs and utilities associated with different HAQ levels were based on data from the cohort studies and cross-sectional surveys. RESULTS: Costs increase and quality of life decreases as RA progresses. In Sweden, total annual costs range from 4,900 dollars to 33,000 dollars per patient, compared with 4,900 dollars to 14,600 dollars in the UK. Cumulative costs over 10 years for patients starting in disease state 1 (HAQ < 0.6) are 54,600 dollars in Sweden and 26,600 dollars in the UK. The cumulative numbers of quality-adjusted life-years (QALYs) are 5.5 and 5.6, respectively. Both costs and QALYs were discounted at 3%. CONCLUSION: The 2 models, which were based on different patient cohorts, reach a similar conclusion in terms of the effect of RA over 10 years. They appear to accurately capture disease progression and its effects and can therefore be useful in estimating the cost-effectiveness of new treatments in RA. 相似文献
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Marianne?de?BritoView authors OrcID profile Gisela?Huebner DedeeF?Murrell Peter?Bullpitt Karin?HartmannEmail author 《Clinical and translational allergy》2018,8(1):37
We report two patients with normocomplementaemic urticarial vasculitis with impressive response to omalizumab. This contrasts recent reports on hypocomplementaemic urticarial vasculitis syndrome, highlighting the need for clinical trials of omalizumab in normocomplementaemic urticarial vasculitis. 相似文献
46.
Indiara Soares Oliveira Leonardo Oliveira Pena Costa Alessandra Narciso Garcia Gisela Cristiane Miyamoto Cristina Maria Nunes Cabral Lucíola da Cunha Menezes Costa 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(4):328-335
Objective
To identify potential prognostic factors that may predict clinical improvement of patients treated with different physical therapy interventions in the short-term.Methods
This is a prospective cohort study. A total of 616 patients with chronic non-specific low back pain treated with interventions commonly used by physical therapists were included. These patients were selected from five randomized controlled trials. Multivariate linear regression models were used to verify if sociodemographic characteristics (age, gender, and marital status), anthropometric variables (height, body mass, and body mass index), or duration of low back pain, pain intensity at baseline, and disability at baseline could be associated with clinical outcomes of pain intensity and disability four weeks after baseline.Results
The predictive variables for pain intensity were age (β = 0.01 points, 95% CI = 0.00 to 0.03, p = 0.03) and pain intensity at baseline (β = 0.23 points, 95% CI = 0.13 to 0.33, p = 0.00), with an explained variability of 4.6%. Similarly, the predictive variables for disability after four weeks were age (β = 0.03 points, 95% CI = 0.00 to 0.06, p = 0.01) and disability at baseline (β = 0.71 points, 95% CI = 0.65 to 0.78, p = 0.00), with an explained variability of 42.1%.Conclusion
Only age, pain at baseline and disability at baseline influenced the pain intensity and disability after four weeks of treatment. The beta coefficient for age was statistically significant, but the magnitude of this association was very small and not clinically important. 相似文献47.
48.
OBJECTIVE AND METHODS: We have previously demonstrated that mechanical loading of cardiac fibroblasts leads to increased synthesis and gene expression of the extracellular matrix protein collagen. We hypothesised that the upregulation of procollagen gene expression in cardiac fibroblasts, in response to cyclic mechanical load, is mediated by one or more members of the MAP kinase family. To test this hypothesis, the effect of mechanical load on the activation of extracellular signal-regulated kinase (ERK) 1/2, p46/54JNK, and p38MAPK was examined in rat cardiac fibroblasts. RESULTS: Peak phosphorylation of ERK 1/2, p38MAPK kinases, and p46/54JNK was observed following 10-20 min of continuous cyclic mechanical load. Mechanical load significantly increased procollagen alpha1(I) mRNA levels up to twofold above static controls after 24 h. This increase was completely abolished by the MEK 1/2 inhibitor U0126, with no effect on basal levels. In contrast, SB203580, a specific inhibitor of p38MAPK, enhanced both basal and stretch-stimulated levels of procollagen mRNA. Consistent with this finding, selective activation of the p38MAPK signalling pathway by expression of MKK6(Glu), a constitutive activator of p38MAPK, significantly reduced procollagen alpha1(I) promoter activity. SB203580-dependent increase in procollagen alpha1(I) was accompanied by ERK 1/2 activation, and inhibition of this pathway completely prevented SB203580-induced procollagen alpha1(I) expression. CONCLUSIONS: These results suggest that mechanical load-induced procollagen alpha1(I) gene expression requires ERK 1/2 activation and that the p38MAPK pathway negatively regulates gene expression in cardiac fibroblasts. These pathways are likely to be key in events leading to matrix deposition during heart growth and remodelling induced by mechanical load. 相似文献
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Bich-Hoai Thi Ton Qingmin Chen Gisela Gaina Catalin Tucureanu Adriana Georgescu Carmen Strungaru Maria-Luiza Flonta Dinah Sah Violeta Ristoiu 《Acta histochemica》2013
The interactions between neurons, immune and immune-like glial cells can initiate the abnormal processes that underlie neuropathic pain. In the peripheral nervous system the resident macrophages may play an important role. In this study we investigated in experimental adult Sprague-Dawley rats how Iba-1 (ionized calcium binding adaptor molecule 1) (+) resident macrophages in the dorsal root ganglion (DRG) are activated after a spinal nerve ligation (SNL) or streptozotocin (STZ)-induced diabetes. The activation profile was defined by comparing the responses of resident macrophages against microglia in the spinal cord as they share a common origin. After SNL, the Iba-1 (+) macrophages in L5 DRG reached their activation peak 5 days later, clustered as satellite cells around large A-neurons, expressed the MHC-II marker, but did not show p-p38 and p-ERK1/2 activation and did not secrete IL-18. After STZ-induced diabetes, the Iba-1 (+) macrophages reached their activation peak 1 week later in L4 and L5 DRG, remained scattered between neurons, expressed the MHC-II marker only in L5 DRG, did not show p-p38 and p-ERK1/2 activation and did not secrete any of the investigated cytokines/chemokines. These responses suggest that depending on the type of lesion DRG Iba-1 (+) resident macrophages have different activation mechanisms, which are dissimilar to those in microglia. 相似文献