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91.
Effect of Iron Hydroxide on Phosphate Removal during Anaerobic Digestion of Activated Sludge 总被引:3,自引:0,他引:3
V. P. Stabnikov S. T.-L. Tay D.-Kh. Tay V. N. Ivanov 《Applied Biochemistry and Microbiology》2004,40(4):376-380
The addition of iron (III) hydroxide during methanogenic digestion of activated sludge by anaerobic sludge displaying an iron-reducing activity resulted in a microbial reduction of iron (III) with the formation of iron (II), capable of precipitating phosphates. The feasibility of eliminating 66.6 to 99.6% of the dissolved phosphate at initial concentrations of 1000 to 3500 mg PO3-
4/l by adding 6420 mg/l iron (III) hydroxide into a reactor for anaerobic fermentation of activated sludge was analyzed. The optimal ratio of iron (III) added to dissolved phosphate removed (mg) providing a 95% removal amounted to 2 : 1. These results may be used in new technology for anaerobic wastewater treatment with phosphate removal. 相似文献
92.
W.-Q. Zhuang J.-H. Tay A. Maszenan S. Tay 《Applied microbiology and biotechnology》2002,58(4):547-554
93.
The isolated kidney perfused with modified Krebs-Henseleit buffer with amino acids yields heavy proteinuria associated with reduced ATP levels characteristic of partial ischemia. These conditions are associated with a similar perfusion time dependent release of degraded vascular [35S]heparan sulfate proteoglycan into the perfusate solution which included a 60% loss of [35S]macromolecular material from the glomerulus after 2h of perfusion. Small amounts of [35S]macromolecular material were found in the urine and lymph. These results demonstrate that partial ischemia promotes a specific response in the overall renal vasculature, probably involving oxygen reactive metabolites, that results in the preferential release of heparan sulphate from the basement membrane and endothelial cells on the luminal side of the capillary wall. 相似文献
94.
L-Rhamnose (6-deoxy-L-mannose) is a constituent carbohydrate unit of microbial, immunogenic heteroglycans and lipopolysaccharides, and often functions as the immunodeterminant group of such immunogens. Two types of anti-rhamnose antibody have now been isolated by affinity chromatography of immune sera obtained from rabbits immunized with vaccines of Streptococcus mutans, strain KI-R, and Streptococcus pneumoniae, type 32. The antibodies of one type were directed at a glycan of L-rhamnose, D-glucose, and D-galactose in the cell wall of S. mutans, and those of the other type, against a capsular glycan of L-rhamnose and D-glucose from S. pneumoniae. The two types of anti-rhamnose antibody were immunologically distinct, and showed no reciprocal cross-reactivity. Additional properties of the two types of antibody were determined; thus, both types of antibody were of the IgG class of immunoglobulins, both possessed molecular weights of 1.45 X 10(5), and both consisted of multiple or isomeric forms. 相似文献
95.
A hybrid anaerobic solid-liquid (HASL) bioreactor is an enhanced two-phase anaerobic system, that consists of a solid waste reactor as the acidification reactor and a wastewater reactor, i.e. an upflow anaerobic sludge blanket (UASB) reactor as the methanogenic reactor. Food waste digestion in HASL bioreactors with pre-acidification and HASL operation stages was investigated in two separate runs. After 8 days of pre-acidification in Run A and 4 days in Run B, total volatile fatty acid (TVFA) and chemical oxygen demand (COD) concentrations in the leachates of both acidification reactors were similar. During HASL operation stage, TVFA and COD removal in the methanogenic phase were 77–100% and 75–95%, respectively. Some 99% of the total methane generated was from the methanogenic phase with a content of 68–70% methane. At the end of operation, about 59–60% of the added volatile solids (VS) were removed with a methane yield of 0.25 l g–1 VS. 相似文献
96.
97.
98.
Lin Xiao Can Chen Zhendong Li Sumin Zhu Johan Ck Tay Xi Zhang Shijun Zha Jieming Zeng Wee Kiat Tan Xin Liu Wee Joo Chng Shu Wang 《Cytotherapy》2018,20(3):420-435
Vγ9Vδ2 T cells are a minor subset of lymphocytes in the peripheral blood that has been extensively investigated for their tolerability, safety and anticancer efficacy. A hindrance to the broad application of these cells for adoptive cellular immunotherapy has been attaining clinically appropriate numbers of Vγ9Vδ2 T cells. Furthermore, Vγ9Vδ2 T cells exist at low frequencies among cancer patients. We, therefore, sought to conceive an economical method that allows for a quick and robust large-scale expansion of Vγ9Vδ2 T cells. A two-step protocol was developed, in which peripheral blood mononuclear cells (PBMCs) from healthy donors or cancer patients were activated with Zometa and interleukin (IL)-2, followed by co-culturing with gamma-irradiated, CD64-, CD86- and CD137L-expressing K562 artificial antigen-presenting cells (aAPCs) in the presence of the anti-CD3 antibody OKT3. We optimized the co-culture ratio of K562 aAPCs to immune cells, and migrated this method to a G-Rex cell growth platform to derive clinically relevant cell numbers in a Good Manufacturing Practice (GMP)-compliant manner. We further include a depletion step to selectively remove αβ T lymphocytes. The method exhibited high expansion folds and a specific enrichment of Vγ9Vδ2 T cells. Expanded Vγ9Vδ2 T cells displayed an effector memory phenotype with a concomitant down-regulated expression of inhibitory immune checkpoint receptors. Finally, we ascertained the cytotoxic activity of these expanded cells by using nonmodified and chimeric antigen receptor (CAR)–engrafted Vγ9Vδ2 T cells against a panel of solid tumor cells. Overall, we report an efficient approach to generate highly functional Vγ9Vδ2 T cells in massive numbers suitable for clinical application in an allogeneic setting. 相似文献
99.
CPEB is a sequence-specific RNA binding protein that regulates translation during vertebrate oocyte maturation. Adult female CPEB knockout mice contained vestigial ovaries that were devoid of oocytes; ovaries from mid-gestation embryos contained oocytes that were arrested at the pachytene stage. Male CPEB null mice also contained germ cells arrested at pachytene. The germ cells from the knockout mice harbored fragmented chromatin, suggesting a possible defect in homologous chromosome adhesion or synapsis. Two CPE-containing synaptonemal complex protein mRNAs, which interact with CPEB in vitro and in vivo, contained shortened poly(A) tails and mostly failed to sediment with polysomes in the null mice. Synaptonemal complexes were not detected in these animals. CPEB therefore controls germ cell differentiation by regulating the formation of the synaptonemal complex. 相似文献
100.
Characterization of Two Subsurface H2-Utilizing Bacteria, Desulfomicrobium hypogeium sp. nov. and Acetobacterium psammolithicum sp. nov., and Their Ecological Roles 下载免费PDF全文
Lee R. Krumholz Steve H. Harris Stephen T. Tay Joseph M. Suflita 《Applied microbiology》1999,65(6):2300-2306
We examined the relative roles of acetogenic and sulfate-reducing bacteria in H2 consumption in a previously characterized subsurface sandstone ecosystem. Enrichment cultures originally inoculated with ground sandstone material obtained from a Cretaceous formation in central New Mexico were grown with hydrogen in a mineral medium supplemented with 0.02% yeast extract. Sulfate reduction and acetogenesis occurred in these cultures, and the two most abundant organisms carrying out the reactions were isolated. Based on 16S rRNA analysis data and on substrate utilization patterns, these organisms were named Desulfomicrobium hypogeium sp. nov. and Acetobacterium psammolithicum sp. nov. The steady-state H2 concentrations measured in sandstone-sediment slurries (threshold concentration, 5 nM), in pure cultures of sulfate reducers (threshold concentration, 2 nM), and in pure cultures of acetogens (threshold concentrations 195 to 414 nM) suggest that sulfate reduction is the dominant terminal electron-accepting process in the ecosystem examined. In an experiment in which direct competition for H2 between D. hypogeium and A. psammolithicum was examined, sulfate reduction was the dominant process. 相似文献