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51.
Polyphosphate kinase genes from full-scale activated sludge plants   总被引:1,自引:0,他引:1  
The performance of enhanced biological phosphorus removal (EBPR) wastewater treatment processes depends on the presence of bacteria that accumulate large quantities of polyphosphate. One such group of bacteria has been identified and named Candidatus Accumulibacter phosphatis. Accumulibacter-like bacteria are abundant in many EBPR plants, but not much is known about their community or population ecology. In this study, we used the polyphosphate kinase gene (ppk1) as a high-resolution genetic marker to study population structure in activated sludge. Ppk1 genes were amplified from samples collected from full-scale wastewater treatment plants of different configurations. Clone libraries were constructed using primers targeting highly conserved regions of ppk1, to retrieve these genes from activated sludge plants that did, and did not, perform EBPR. Comparative sequence analysis revealed that ppk1 fragments were retrieved from organisms affiliated with the Accumulibacter cluster from EBPR plants but not from a plant that did not perform EBPR. A new set of more specific primers was designed and validated to amplify a 1,100 bp ppk1 fragment from Accumulibacter-like bacteria. Our results suggest that the Accumulibacter cluster has finer-scale architecture than previously revealed by 16S ribosomal RNA-based analyses. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
52.
We identified nine individuals from three unrelated Turkish families with a unique autosomal recessive syndrome characterized by type I microtia, microdontia, and profound congenital deafness associated with a complete absence of inner ear structures (Michel aplasia). We later demonstrated three different homozygous mutations (p.S156P, p.R104X, and p.V206SfsX117) in the fibroblast growth factor 3 (FGF3) gene in affected members of these families, cosegregating with the autosomal recessive transmission as a completely penetrant phenotype. These findings demonstrate the involvement of FGF3 mutations in a human malformation syndrome for the first time and contribute to our understanding of the role this gene plays in embryonic development. Of particular interest is that the development of the inner ear is completely disturbed at a very early stage--or the otic vesicle is not induced at all--in all of the affected individuals who carried two mutant FGF3 alleles.  相似文献   
53.
Polychlorinated biphenyls (PCBs) are persistent environmental pollutants. This study compared effects of two PCB mixtures, Aroclors 1221 (A1221) and 1254 (A1254) on serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea, creatinine and uric acid in female rats. Histopathological changes in the liver and kidney were also examined. A group of adult Wistar rats served as controls. Groups II and III were subcutaneously injected with A1221 and A1254 at 10 mg/kg every other day for 6 weeks. At the end of this period, all animals were decapitated and blood samples were collected. Serum urea, creatinine, uric acid, ALT, AST and ALP levels were determined. Liver and kidney were collected for histopathological examination. They were fixed in formaldehyde and processed for light microscopy. Both A1221 and 1254 significantly elevated serum ALT (p < 0.05) and AST (p < 0.01) levels compared to the control group. Serum ALP values were significantly increased by A1221 (p < 0.05), but they were unaffected in the A1254 group. Treatment with both A1221 and A1254 significantly increased serum levels of urea (p < 0.05), creatinine (p < 0.01) and uric acid (except in the A1221 group; p < 0.005). Distinct histopathological changes including renal corpuscular atrophy, peritubular vascular congestion and dilated cortical tubules, sinusoidal dilatation, congestion and mononuclear cell infiltration were observed. These findings suggest that PCBs may cause nephrotoxicity and hepatotoxicity in female rats.  相似文献   
54.
We investigated the protective role of aminoguanidine (AG) in rat liver injury induced by chronic biliary obstruction. Secondary biliary cirrhosis was induced by bile duct ligation for 14 days. Swiss albino rats were divided into three groups: Common bile duct ligated (CBDL) rats; Group A, CBDL rats treated with AG as Group B and simple laparotomy group known as the Sham group; Group C. Group B received 200 mg/kg of AG intraperitoneally daily throughout 14 days. The present data showed decreased gama glutamyl transferase (GGT), aspartate aminotransferase (AST), bilirubin and alanine aminotransferase (ALT) levels in the AG treated rats, when compared with CBDL rats (p < 0.05). In the AG treated rats, tissue levels of malondialdehyde (MDA) were significantly lower than that in CBDL rats (p < 0.001). Although the levels of glutathione (GSH) in AG treated rats were higher and myeloperoxidase (MPO) were lower than that in CBDL rats, the difference was not statistically significant (p > 0.05). The levels of interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha) were significantly lower and although the levels of interleukin-6 (IL-6) were lower in AG treated rats than that in CBDL rats, the difference was not statistically significant. Administration of AG in the rats with biliary obstruction resulted in inhibition of ductular proliferation and portal inflammation. The present study demonstrates that intraperitoneal administration of AG in CBDL rats maintains antioxidant defenses, reduces liver oxidative and cytokine damage and ductular proliferation and portal inflammation. This effect of AG may be useful in the preservation of liver injury in cholestasis.  相似文献   
55.
Emanuel syndrome results from +der(22)t(11q23;22q11). Cleft palate, ear anomalies, heart defects, genital anomalies, hypotonia, and mental retardation are the main features of the syndrome. We report a nine-year-old boy with the t(11;22)(q23;q11) chromosome, transmitted in an unbalanced fashion from his mother, and originated in the maternal grandmother's meiosis. In addition to mental retardation, hypotonia, craniofacial anomalies, and cryptorchidism, he has novel findings such as, joint hyperextensibility, left liver lobe agenesis, left sided malposition of the gallbladder and pancreas hypoplasia. This is the first report associating these features with Emanuel syndrome.  相似文献   
56.
CDP-choline is an endogenous metabolite in phosphatidylcholine biosynthesis. Exogenous administration of CDP-choline has been shown to affect brain metabolism and to exhibit neuroprotective actions. On the other hand, little is known regarding its peripheral actions. Intraperitoneal administration of CDP-choline (200-600 micromol/kg) induced a dose- and time-dependent hyperglycemia in rats. Hyperglycemic response to CDP-choline was associated with several-fold elevations in serum concentrations of CDP-choline and its metabolites. Intraperitoneal administration of phosphocholine, choline, cytidine, cytidine monophosphate, cytidine diphosphate, cytidine triphosphate, uridine, uridine monophosphate, uridine diphosphate and uridine triphosphate also produced significant hyperglycemia. Pretreatment with atropine methyl nitrate failed to alter the hyperglycemic responses to CDP-choline and its metabolites whereas hexamethonium, the ganglionic nicotinic receptor antagonist which blocks nicotinic cholinergic neurotransmission at the autonomic ganglionic level, blocked completely the hyperglycemia induced by CDP-choline, phosphocholine and choline, and attenuated the hyperglycemic response to cytidine monophosphate and cytidine. Increased blood glucose following CDP-choline, phosphocholine and choline was accompanied by elevated plasma catecholamine concentrations. Hyperglycemia elicited by CDP-choline and its metabolites was entirely blocked either by pretreatment with a nonselective -adrenoceptor antagonist phentolamine or by the 2-adrenoceptor antagonist, yohimbine. Hyperglycemic responses to CDP-choline, choline, cytidine monophosphate and cytidine were not affected by chemical sympathectomy, but were prevented by bilateral adrenalectomy. Phosphocholine-induced hyperglycemia was attenuated by bilateral adrenalectomy or by chemical sympathectomy. These data show that CDP-choline and its metabolites induce hyperglycemia which is mediated by activation of ganglionic nicotinic receptors and stimulation of catecholamine release that subsequently activates 2-adrenoceptors.  相似文献   
57.
Amino Acids - Behçet disease (BD) is an inflammatory, multisystemic vasculitis of unknown etiopathogenesis. However, innate and adaptive immune system involvement and immune-mediated networks...  相似文献   
58.
Here we study the intact stoichiometry and top-down fragmentation behavior of three integral membrane proteins which were natively reconstituted into detergent micelles: the mechano-sensitive ion channel of large conductance (MscL), the Kirbac potassium channel and the p7 viroporin from the hepatitis C virus. By releasing the proteins under nondenaturing conditions inside the mass spectrometer, we obtained their oligomeric sizes. Increasing the ion activation (collision energy) causes unfolding and subsequent ejection of a highly charged monomer from the membrane protein complexes. Further increase of the ion activation then causes collision-induced dissociation (CID) of the ejected monomers, with fragments observed which were predominantly found to stem from membrane-embedded regions. These experiments show how in a single experiment, we can probe the relation between higher-order structure and protein sequence, by combining the native MS data with fragmentation obtained from top-down MS.  相似文献   
59.
Sleep and Biological Rhythms - The aim of this study was to assess the presence of Restless Leg Syndrome (RLS) in patients with poliomyelitis, and associated factors. Forty-six patients with...  相似文献   
60.
Fibrous poly(styrene-d-glycidylmethacrylate) (P(S-GMA)) brushes were grafted on poly(styrene-divinylbenzene) (P(S-DVB)) beads using surface initiated-atom transfer radical polymerization (SI-ATRP). Tetraethyldiethylenetriamine (TEDETA) ligand was incorporated on P(GMA) block. The multi-modal ligand attached beads were used for reversible immobilization of catalase. The influences of pH, ionic strength and initial catalase concentration on the immobilization capacities of the P(S-DVB)-g-P(S-GMA)-TEDETA beads have been investigated. Catalase adsorption capacity of P(S-DVB-g-P(S-GMA)-TEDETA beads was found to be 40.8 ± 1.7 mg/g beads at pH 6.5 (with an initial catalase concentration 1.0 mg/mL). The Km value for immobilized catalase on the P(S-DVB-g-P(S-GMA)-TEDETA beads (0.43 ± 0.02 mM) was found about 1.7-fold higher than that of free enzyme (0.25 ± 0.03 mM). Optimum operational temperature and pH was increased upon immobilization. The same support was repeatedly used five times for immobilization of catalase after regeneration without significant loss in adsorption capacity or enzyme activity.  相似文献   
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