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991.
Mirosław Szyłak-Szydłowski Teresa Korniłłowicz-Kowalska 《Central European Journal of Biology》2012,7(2):250-258
The paper discusses the dynamics of the accumulation of microscopic fungi, depending on the sludge load (Bx), in activated sludge used for landfill leachate pretreatment. The propagule washout from the sludge into pretreated leachates is determined, including genera and species that may threaten environmental health. An increased accumulation of microscopic fungi in sludge flocs occurred at Bx=0.23−0.45 mg chemical oxygen demand (COD) mg−1 d−1. Microscopic fungi were eluted at the maximal Bx value tested of 1.64 mg COD mg−1 d−1. Both the activated sludge and the leachate runoff from the sequencing batch reactor (SBR) pose health risks to the environment due to the occurrence of fungi such as Aspergillus fumigatus, Purpureocillium lilacinum, Cyberlindnera jadinii (C. utilis), Geotrichum candidum and G. fragrans. Their count is sufficient to cause multi-organ infections in homeothermal animals and in humans. 相似文献
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993.
Sean V. Murphy Rebecca Lim Philip Heraud Marian Cholewa Mark Le Gros Martin D. de Jonge Daryl L. Howard David Paterson Courtney McDonald Anthony Atala Graham Jenkin Euan M. Wallace 《PloS one》2012,7(9)
Cystic fibrosis, an autosomal recessive disorder caused by a mutation in a gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR), remains a leading cause of childhood respiratory morbidity and mortality. The respiratory consequences of cystic fibrosis include the generation of thick, tenacious mucus that impairs lung clearance, predisposing the individual to repeated and persistent infections, progressive lung damage and shortened lifespan. Currently there is no cure for cystic fibrosis. With this in mind, we investigated the ability of human amnion epithelial cells (hAECs) to express functional CFTR. We found that hAECs formed 3-dimensional structures and expressed the CFTR gene and protein after culture in Small Airway Growth Medium (SAGM). We also observed a polarized CFTR distribution on the membrane of hAECs cultured in SAGM, similar to that observed in polarized airway cells in vivo. Further, hAECs induced to express CFTR possessed functional iodide/chloride (I−/Cl−) ion channels that were inhibited by the CFTR-inhibitor CFTR-172, indicating the presence of functional CFTR ion channels. These data suggest that hAECs may be a promising source for the development of a cellular therapy for cystic fibrosis. 相似文献
994.
Radice F Orlandi V Massa V Battini V Bertoni G Reineke W Barbieri P 《Applied microbiology and biotechnology》2007,75(5):1111-1118
An Arthrobacter strain, able to utilize 4-chlorobenzoic acid as the sole carbon and energy source, was isolated and characterized. The first step of the catabolic pathway was found to proceed via a hydrolytic dehalogenation that leads to the formation of 4-hydroxybenzoic acid. The dehalogenase encoding genes (fcb) were sequenced and found highly homologous to and organized as those of other 4-chlorobenzoic acid degrading Arthrobacter strains. The fcb genes were cloned and successfully expressed in the heterologous host Pseudomonas putida PaW340 and P. putida KT2442 upper TOL, which acquired the ability to grow on 4-chlorobenzoic acid and 4-chlorotoluene, respectively. The cloned dehalogenase displayed a high specificity for para-substituted haloaromatics with affinity Cl > Br > I > F, in the order. 相似文献
995.
Liselotte W. Wijsman Anton J. M. de Craen Stella Trompet Jacobijn Gussekloo David J. Stott Nicolas Rodondi Paul Welsh J. Wouter Jukema Rudi G. J. Westendorp Simon P. Mooijaart 《PloS one》2013,8(3)
Background
Subclinical thyroid dysfunction has been implicated as a risk factor for cognitive decline in old age, but results are inconsistent. We investigated the association between subclinical thyroid dysfunction and cognitive decline in the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER).Methods
Prospective longitudinal study of men and women aged 70–82 years with pre-existing vascular disease or more than one risk factor to develop this condition (N = 5,154). Participants taking antithyroid medications, thyroid hormone supplementation and/or amiodarone were excluded. Thyroid function was measured at baseline: subclinical hyper- and hypothyroidism were defined as thyroid stimulating hormones (TSH) <0.45 mU/L or >4.50 mU/L respectively, with normal levels of free thyroxine (FT4). Cognitive performance was tested at baseline and at four subsequent time points during a mean follow-up of 3 years, using five neuropsychological performance tests.Results
Subclinical hyperthyroidism and hypothyroidism were found in 65 and 161 participants, respectively. We found no consistent association of subclinical hyper- or hypothyroidism with altered cognitive performance compared to euthyroid participants on the individual cognitive tests. Similarly, there was no association with rate of cognitive decline during follow-up.Conclusion
We found no consistent evidence that subclinical hyper- or hypothyroidism contribute to cognitive impairment or decline in old age. Although our data are not in support of treatment of subclinical thyroid dysfunction to prevent cognitive dysfunction in later life, only large randomized controlled trials can provide definitive evidence. 相似文献996.
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Increased resource availability and feedbacks with soil biota have both been invoked as potential mechanisms of plant invasion. Nitrogen (N) deposition can enhance invasion in some ecosystems, and this could be the result of increased soil N availability as well as shifts in soil biota. In a two-phase, full-factorial greenhouse experiment, we tested effects of N availability and N-impacted soil communities on growth responses of three Mediterranean plant species invasive in California: Bromus diandrus, Centaurea melitensis, and Hirschfeldia incana. In the first phase, plants were grown individually in pots and inoculated with sterile soil, soil from control field plots or soil from high N addition plots, and with or without supplemental N. In the second phase, we grew the same species in soils conditioned in the first phase. We hypothesized growth responses would differ across species due to species-specific relationships with soil biota, but overall increased N availability and N-impacted soil communities would enhance plant growth. In the first phase, Centaurea had the greatest growth response when inoculated with N-impacted soil, while Bromus and Hirschfeldia performed best in low N soil communities. However, in phase two all species exhibited positive growth responses in N-impacted soil communities under high N availability. While species may differ in responses to soil biota and N, growth responses to soils conditioned by conspecifics appear to be most positive in all species under high N availability and/or in soil communities previously impacted by simulated N deposition. Our results suggest N deposition could facilitate invasion due to direct impacts of soil N enrichment on plant growth, as well as through feedbacks with the soil microbial community. 相似文献