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101.
Aerobic biodegradation of propylene glycol by soil bacteria 总被引:1,自引:0,他引:1
Giuseppe Toscano Lucia Cavalca M. Letizia Colarieti Rosalia Scelza Riccardo Scotti Maria A. Rao Vincenza Andreoni Sonia Ciccazzo Guido Greco 《Biodegradation》2013,24(5):603-613
Propylene glycol (PG) is a main component of aircraft deicing fluids and its extensive use in Northern airports is a source of soil and groundwater contamination. Bacterial consortia able to grow on PG as sole carbon and energy source were selected from soil samples taken along the runways of Oslo Airport Gardermoen site (Norway). DGGE analysis of enrichment cultures showed that PG-degrading populations were mainly composed by Pseudomonas species, although Bacteroidetes were found, as well. Nineteen bacterial strains, able to grow on PG as sole carbon and energy source, were isolated and identified as different Pseudomonas species. Maximum specific growth rate of mixed cultures in the absence of nutrient limitation was 0.014 h?1 at 4 °C. Substrate C:N:P molar ratios calculated on the basis of measured growth yields are in good agreement with the suggested values for biostimulation reported in literature. Therefore, the addition of nutrients is suggested as a suitable technique to sustain PG aerobic degradation at the maximum rate by autochthonous microorganisms of unsaturated soil profile. 相似文献
102.
The regional specialization of brain function has been well documented in the mouse and fruitfly. The expression of regulatory factors in specific regions of the brain during development suggests that they function to establish or maintain this specialization. Here, we focus on two such factors—the Drosophila cephalic gap genes empty spiracles (ems) and orthodenticle (otd), and their vertebrate homologues Emx1/2 and Otx1/2—and review novel insight into their multiple crucial roles in the formation of complex sensory systems. While the early requirement of these genes in specification of the neuroectoderm has been discussed previously, here we consider more recent studies that elucidate the later functions of these genes in sensory system formation in vertebrates and invertebrates. These new studies show that the ems and Emx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective olfactory systems. Moreover, they demonstrate that the otd and Otx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective visual systems. Based on these recent experimental findings, we discuss the possibility that the olfactory and visual systems of flies and mice share a common evolutionary origin, in that the conserved visual and olfactory circuit elements derive from conserved domains of otd/Otx and ems/Emx action in the urbilaterian ancestor. 相似文献
103.
éric Claeyssen Sonia Dorion Audrey Clendenning Jiang Zhou He Owen Wally Jingkui Chen Evgenia L. Auslender Marie-Claude Moisan Mario Jolicoeur Jean Rivoal 《PloS one》2013,8(1)
The metabolism of potato (Solanum tuberosum) roots constitutively over- and underexpressing hexokinase (HK, EC 2.7.1.1) was examined. An 11-fold variation in HK activity resulted in altered root growth, with antisense roots growing better than sense roots. Quantification of sugars, organic acids and amino acids in transgenic roots demonstrated that the manipulation of HK activity had very little effect on the intracellular pools of these metabolites. However, adenylate and free Pi levels were negatively affected by an increase in HK activity. The flux control coefficient of HK over the phosphorylation of glucose was measured for the first time in plants. Its value varied with HK level. It reached 1.71 at or below normal HK activity value and was much lower (0.32) at very high HK levels. Measurements of glycolytic flux and O2 uptake rates demonstrated that the differences in glucose phosphorylation did not affect significantly glycolytic and respiratory metabolism. We hypothesized that these results could be explained by the existence of a futile cycle between the pools of hexose-Ps and carbohydrates. This view is supported by several lines of evidence. Firstly, activities of enzymes capable of catalyzing these reactions were detected in roots, including a hexose-P phosphatase. Secondly, metabolic tracer experiments using 14C-glucose as precursor showed the formation of 14C-fructose and 14C-sucrose. We conclude that futile cycling of hexose-P could be partially responsible for the differences in energetic status in roots with high and low HK activity and possibly cause the observed alterations in growth in transgenic roots. The involvement of HK and futile cycles in the control of glucose-6P metabolism is discussed. 相似文献
104.
105.
Eliane Volchan Isabel A. David Gisella Tavares Billy M. Nascimento Jose M. Oliveira Sonia Gleiser Andre Szklo Cristina Perez Tania Cavalcante Mirtes G. Pereira Leticia Oliveira 《PloS one》2013,8(8)
Objective
The use of pictorial warning labels on cigarette packages is one of the provisions included in the first ever global health treaty by the World Health Organization against the tobacco epidemic. There is substantial evidence demonstrating the effectiveness of graphic health warning labels on intention to quit, thoughts about health risks and engaging in cessation behaviors. However, studies that address the implicit emotional drives evoked by such warnings are still underexplored. Here, we provide experimental data for the use of pictorial health warnings as a reliable strategy for tobacco control.Methods
Experiment 1 pre-tested nineteen prototypes of pictorial warnings to screen for their emotional impact. Participants (n = 338) were young adults balanced in gender, smoking status and education. Experiment 2 (n = 63) tested pictorial warnings (ten) that were stamped on packs. We employed an innovative set-up to investigate the impact of the warnings on the ordinary attitude of packs’ manipulation, and quantified judgments of warnings’ emotional strength and efficacy against smoking.Findings
Experiment 1 revealed that women judged the warning prototypes as more aversive than men, and smokers judged them more aversive than non-smokers. Participants with lower education judged the prototypes more aversive than participants with higher education. Experiment 2 showed that stamped warnings antagonized the appeal of the brands by imposing a cost to manipulate the cigarette packs, especially for smokers. Additionally, participants’ judgments revealed that the more aversive a warning, the more it is perceived as effective against smoking.Conclusions
Health warning labels are one of the key components of the integrated approach to control the global tobacco epidemic. The evidence presented in this study adds to the understanding of how implicit responses to pictorial warnings may contribute to behavioral change. 相似文献106.
Madhura S. Mehta Sonia C. Dolfi Roman Bronfenbrener Erhan Bilal Chunxia Chen Dirk Moore Yong Lin Hussein Rahim Seena Aisner Romona D. Kersellius Jessica Teh Suzie Chen Deborah L. Toppmeyer Dan J. Medina Shridar Ganesan Alexei Vazquez Kim M. Hirshfield 《PloS one》2013,8(7)
Several epidemiological studies have suggested a link between melanoma and breast cancer. Metabotropic glutamate receptor 1 (GRM1), which is involved in many cellular processes including proliferation and differentiation, has been implicated in melanomagenesis, with ectopic expression of GRM1 causing malignant transformation of melanocytes. This study was undertaken to evaluate GRM1 expression and polymorphic variants in GRM1 for associations with breast cancer phenotypes. Three single nucleotide polymorphisms (SNPs) in GRM1 were evaluated for associations with breast cancer clinicopathologic variables. GRM1 expression was evaluated in human normal and cancerous breast tissue and for in vitro response to hormonal manipulation. Genotyping was performed on genomic DNA from over 1,000 breast cancer patients. Rs6923492 and rs362962 genotypes associated with age at diagnosis that was highly dependent upon the breast cancer molecular phenotype. The rs362962 TT genotype also associated with risk of estrogen receptor or progesterone receptor positive breast cancer. In vitro analysis showed increased GRM1 expression in breast cancer cells treated with estrogen or the combination of estrogen and progesterone, but reduced GRM1 expression with tamoxifen treatment. Evaluation of GRM1 expression in human breast tumor specimens demonstrated significant correlations between GRM1 staining with tissue type and molecular features. Furthermore, analysis of gene expression data from primary breast tumors showed that high GRM1 expression correlated with a shorter distant metastasis-free survival as compared to low GRM1 expression in tamoxifen-treated patients. Additionally, induced knockdown of GRM1 in an estrogen receptor positive breast cancer cell line correlated with reduced cell proliferation. Taken together, these findings suggest a functional role for GRM1 in breast cancer. 相似文献
107.
Davina Tondeleir Benjamin Drogat Karolina Slowicka Karima Bakkali Sonia Bartunkova Steven Goossens Jody J. Haigh Christophe Ampe 《PloS one》2013,8(6)
The functions of actin family members during development are poorly understood. To investigate the role of beta-actin in mammalian development, a beta-actin knockout mouse model was used. Homozygous beta-actin knockout mice are lethal at embryonic day (E)10.5. At E10.25 beta-actin knockout embryos are growth retarded and display a pale yolk sac and embryo proper that is suggestive of altered erythropoiesis. Here we report that lack of beta-actin resulted in a block of primitive and definitive hematopoietic development. Reduced levels of Gata2, were associated to this phenotype. Consistently, ChIP analysis revealed multiple binding sites for beta-actin in the Gata2 promoter. Gata2 mRNA levels were almost completely rescued by expression of an erythroid lineage restricted ROSA26-promotor based GATA2 transgene. As a result, erythroid differentiation was restored and the knockout embryos showed significant improvement in yolk sac and embryo vascularization. These results provide new molecular insights for a novel function of beta-actin in erythropoiesis by modulating the expression levels of Gata2 in vivo. 相似文献
108.
Wan C. Tan Jean Bourbeau Paul Hernandez Kenneth R. Chapman Robert Cowie J. Mark FitzGerald Shawn Aaron Darcy D. Marciniuk Francois Maltais A. Sonia Buist Denis E. O’Donnell Don D. Sin 《PloS one》2013,8(3)
Background
The relationship between patient-reported symptoms and objective measures of lung function is poorly understood.Aim
To determine the association between responsiveness to bronchodilator and respiratory symptoms in random population samples.Methods
4669 people aged 40 years and older from 8 sites in Canada completed interviewer-administered respiratory questionnaires and performed spirometry before and after administration of 200 ug of inhaled salbutamol. The effect of anthropometric variables, smoking exposure and doctor-diagnosed asthma (DDA) on bronchodilator responsiveness in forced expiratory volume in 1 second (FEV1) and in forced vital capacity (FVC) were evaluated. Multiple logistic regression was used to test for association between quintiles of increasing changes in FEV1 and in FVC after bronchodilator and several respiratory symptoms.Results
Determinants of bronchodilator change in FEV1 and FVC included age, DDA, smoking, respiratory drug use and female gender [p<0.005 to p<0.0001 ]. In subjects without doctor-diagnosed asthma or COPD, bronchodilator response in FEV1 was associated with wheezing [p for trend<0.0001], while bronchodilator response for FVC was associated with breathlessness. [p for trend <0.0001].Conclusions
Bronchodilator responsiveness in FEV1 or FVC are associated with different respiratory symptoms in the community. Both flow and volume bronchodilator responses are useful parameters which together can be predictive of both wheezing and breathlessness in the general population. 相似文献109.
John J. Openshaw Sonia Hegde Hossain M. S. Sazzad Salah Uddin Khan M. Jahangir Hossain Jonathan H. Epstein Peter Daszak Emily S. Gurley Stephen P. Luby 《EcoHealth》2016,13(1):39-48
We used data on feeding practices and domestic animal health gathered from 207 Bangladeshi villages to identify any association between grazing dropped fruit found on the ground or owners directly feeding bat- or bird-bitten fruit and animal health. We compared mortality and morbidity in domestic animals using a mixed effects model controlling for village clustering, herd size, and proxy measures of household wealth. Thirty percent of household heads reported that their animals grazed on dropped fruit and 20% reported that they actively fed bitten fruit to their domestic herds. Household heads allowing their cattle to graze on dropped fruit were more likely to report an illness within their herd (adjusted prevalence ratio 1.17, 95% CI 1.02–1.31). Household heads directly feeding goats bitten fruit were more likely to report illness (adjusted prevalence ratio 1.35, 95% CI 1.16–1.57) and deaths (adjusted prevalence ratio 1.64, 95% CI 1.13–2.4). Reporting of illnesses and deaths among goats rose as the frequency of feeding bitten fruit increased. One possible explanation for this finding is the transmission of bat pathogens to domestic animals via bitten fruit consumption. 相似文献