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Members of the uncultured bacterial genus Candidatus Accumulibacter are capable of intracellular accumulation of inorganic phosphate in activated sludge wastewater treatment plants (WWTPs) performing enhanced biological phosphorus removal, but were also recently shown to inhabit freshwater and estuarine sediments. Additionally, metagenomic sequencing of two bioreactor cultures enriched in Candidatus Accumulibacter, but housed on separate continents, revealed the potential for global dispersal of particular Candidatus Accumulibacter strains, which we hypothesize is facilitated by the ability of Candidatus Accumulibacter to persist in environmental habitats. In the current study, we used sequencing of a phylogenetic marker, the ppk1 gene, to characterize Candidatus Accumulibacter populations in diverse environments, at varying distances from WWTPs. We discovered several new lineages of Candidatus Accumulibacter which had not previously been detected in WWTPs, and also uncovered new diversity and structure within previously detected lineages. Habitat characteristics were found to be a key determinant of Candidatus Accumulibacter lineage distribution while, as predicted, geographic distance played little role in limiting dispersal on a regional scale. However, on a local scale, enrichment of particular Candidatus Accumulibacter lineages in WWTP appeared to impact local environmental populations. These results provide evidence of ecological differences among Candidatus Accumulibacter lineages.  相似文献   
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Four new platinum(II) complexes of 3-aminocyclopentanespiro-5-hydantoin (acpsh) and 3-aminocycloheptanespiro-5-hydantoin (achpsh) were synthesized and characterized by elemental analysis, IR and 1NMR spectra. The spectral analyses indicated a cis-square planar structure of the complexes with ligands coordinated via the NH2 group. The complexes were evaluated for in vitro cytotoxicity in murine erythroleukemia (MEL) cells, clone F4N, using cell-growth and macromolecular synthesis assay. The compounds, with exception of [Pt(NH3)(achpsh)Cl2] (IV), exhibited much lower cytotoxicity than that of cisplatin (DDP). Compound IV was nearly as cytotoxic as DDP. The new complexes exerted low antibacterial activity as assessed by seven bacterial strains.  相似文献   
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Lassa fever (LF) is an acute viral haemorrhagic illness with various non-specific clinical manifestations. Neurological symptoms are rare at the early stage of the disease, but may be seen in late stages, in severely ill patients.The aim of this study was to describe the epidemiological evolution, socio-demographic profiles, clinical characteristics, and outcomes of patients seen during two Lassa fever outbreaks in Ebonyi State, between December 2017 and December 2018.Routinely collected clinical data from all patients admitted to the Virology Centre of the hospital during the period were analysed retrospectively. Out of a total of 83 cases, 70(84.3%) were RT-PCR confirmed while 13 (15.7%) were probable cases. Sixty-nine (83.1%) patients were seen in outbreak 1 of whom 53.6% were urban residents, while 19%, 15%, and 10% were farmers, students and health workers respectively. There were 14 (16.8%) patients, seen in second outbreak with 92.9% rural residents. There were differences in clinical symptoms, signs and laboratory findings between the two outbreaks. The case fatality rates were 29.9% in outbreak 1 and 85.7% for outbreak 2. Neurological features and abnormal laboratory test results were associated with higher mortality rate, seen in outbreak 2. This study revealed significant differences between the two outbreaks. Of particular concern was the higher case fatality during the outbreak 2 which may be from a more virulent strain of the Lassa virus. This has important public health implications and further molecular studies are needed to better define its characteristics.  相似文献   
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Recent advances in tissue engineering technology suggest its application in different medical fields, including periodontology. There are some reports of new non-enzymatic methods of isolating human gingival fibroblast for short-time cultivation in vitro to be used in autologous gingival augmentation. The aim of this study was to obtain a simple and established method of culturing human gingival fibroblasts. The authors developed a recurrent method that can be successfully used in autologous gingival augmentation.  相似文献   
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From a soil sample a new microorganism was isolated, described and identified as Streptomyces lisandri nov. sp. In submerged fermentation in a suitable culture medium this streptomycete produces three new related compounds, axenomycins A, B and D. Data on the anthelmintic, antiprotozoal and antifungal activities in vitro are reported.  相似文献   
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