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61.
Perchloric acid extracts of radiation-induced fibrosarcoma (RIF-1) tumors grown in mice have been analyzed by multinuclear NMR spectroscopy and by various chromatographic methods. This analysis has permitted the unambiguous assignment of the 31P resonances observed in vivo to specific phosphorus-containing metabolites. The region of the in vivo spectra generally assigned to sugar phosphates has been found in RIF-1 tumors to contain primarily phosphorylethanolamine and phosphorylcholine rather than glycolytic intermediates. Phosphocreatine was observed in extracts of these tumor cells grown in culture as well as in the in vivo spectra, indicating that at least some of the phosphocreatine observed in vivo arises from the tumor itself and not from normal tissues. In the 31P-NMR spectra of the perchloric acid extract, resonances originating from purine and pyrimidine nucleoside di- and triphosphate were resolved. HPLC analyses of the nucleotide pool indicate that adenine derivatives were the most abundant components, but other nucleotides were present in significant amounts. The 1H and 13C resonance assignments of the majority of metabolites present in RIF-1 extracts have also been made. Of particular importance is the ability to observe lactate, the levels of which may provide a noninvasive measure of glycolysis in these cells in both the in vivo and in vitro states. In addition, the aminosulfonic acid, taurine, was found in high levels in the tumor extracts.  相似文献   
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Anaerobic bioreactors supplemented with membrane technology have become quite popular, owing to their favorable energy recovery characteristics. In this study, a lab-scale anaerobic Membrane Bioreactor (AnMBR) was assessed in experimental treatments of pre-settled dilute municipal wastewater obtained from a full-scaled wastewater treatment plant. The MBR system was operated in continuous flow mode for 440 days. To evaluate the performance of the AnMBR under various loading rates, the hydraulic retention time (HRT) was reduced in a stepwise manner (from 2 to 0.5 days). Afterward, the mixed liquor suspended solids (MLSS) were reduced from 7,000 to 3,000 mg/L in increments of 1,000 mg/L, resulting in a decrease in solids retention time (SRT) at a constant HRT of 1.0 day. The soluble chemical oxygen demand (SCOD) concentration in the feed varied between 38 and 131 mg/L, whereas the average permeate SCOD ranged between 18 and 37 mg/L, reflecting excellent effluent quality. The AnMBR performance in terms of COD removal proved stable, despite variations in influent characteristics and HRT and SRT changes. The concentration of extracellular polymeric substance (EPS) was reduced with decreases in HRT from 42 to 22 mg VS/mg of MLSS, thereby indicating that the increased biomass concentration biodegraded the EPS at lower HRTs. AnMBR is, therefore, demonstrably a feasible option for the treatment of dilute wastewater with separate stage nitrogen and phosphorus removal processes.  相似文献   
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Aspergillus japonicus andA. foetidus were found to solubilize, five types of Indian rock phosphates at pH 8 and 9. Solubilization was higher in the presence of pyrite than in controls lacking either pyrite or fungal, inoculum. Both the aspergilli were found to be good pyrite solubilizers and could grow over a wide pH range. Solubilization of rock phosphates was the result of organic acid release and pyrite oxidation.  相似文献   
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Type 2 diabetes mellitus (T2DM) is linked with Glycogen synthase kinase-3 β.Therefore, it is ofinterest to document molecular docking analysis data of compounds from Justica adhatoda L with glycogen synthase kinase-3 β. We report the binding features of ethambutol, pyrazinamide, stigmasterol and vasicoline with GSK-3 β.  相似文献   
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Cryopreservation is a valuable tool that could potentially create an alternate plant preservation strategy for species at risk such as Hill’s thistle. The present study is focused on a successful paradigm involving conservation, propagation and redistribution (CPR), emaphasizing the usefulness of cryopreservation techniques for plant conservation using Hill’s thistle (Cirsium hillii. (Canby) Fernald). A cryopreservation protocol was established using the droplet-vitrification method for 5-week-old shoot tips of in vitro grown cultures. More than 90% of shoot tips showed regrowth and nearly all regenerated plants were able to survive in the greenhouse. The survival, growth, and development of plants from cryopreserved shoot buds and their performance in field conditions were all comparable or better than the plants from non-cryopreserved buds. Reintroduced plants flowered following overwintering and the magnitude of flowering was site dependent with ca. 80% flowering observed in one site. The site dependent flowering patterns were assessed using phytohormone profiling and compared to herbivory, a common biotic stressor of these plants. Lower tryptophan concentrations led to higher flowering except in alvars, where the limestone resisted root penetration resulting in poor flowering. The presence of tryptamine in the greenhouse acclimatized or alvar field leaves suggested the preparedness of the plants for herbivory/grazing. Serotonin and melatonin concentrations were lower in flowering plants and in sites where the biotic/abiotic stress was minimal. This study provides evidence of the effectiveness of the CPR model in species recovery programs for endangered species. Physiological characterization of plants developed from cryopreserved tissues can be useful for fundamental and applied research in stress adaptation and reproductive biology of plants.

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68.
Baculoviruses have enormous potential for use as biopesticides to control insect pest populations without the adverse environmental effects posed by the widespread use of chemical pesticides. However, continuous baculovirus production is susceptible to DNA mutation and the subsequent production of defective interfering particles (DIPs). The amount of DIPs produced and their genome length distribution are of great interest not only for baculoviruses but for many other DNA and RNA viruses. In this study, we elucidate this aspect of virus replication using baculovirus as an example system and both experimental and modeling studies. The existing mathematical models for the virus replication process consider DIPs as a lumped quantity and do not consider the genome length distribution of the DIPs. In this study, a detailed population balance model for the cell‐virus culture is presented, which predicts the genome length distribution of the DIP population along with their relative proportion. The model is simulated using the kinetic Monte Carlo algorithm, and the results agree well with the experimental results. Using this model, a practical strategy to maintain the DIP fraction to near to its maximum and minimum limits has been demonstrated.  相似文献   
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Probiotics and Antimicrobial Proteins - The outbreak of diseases leading to substantial loss is a major bottleneck in aquaculture. Over the last decades, the concept of using feed probiotics was...  相似文献   
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