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61.
In the present study possibility of coupling stripper to remove ammonia to the UASB reactor treating poultry litter leachate was studied to enhance the overall performance of the reactor. UASB reactor with stripper as ammonia inhibition control mechanism exhibited better performance in terms of COD reduction (96%), methane yield (0.26m(3)CH(4)/kg COD reduced), organic loading rate (OLR) (18.5kg COD m(-3)day(-1)) and Hydraulic residence time (HRT) (12h) compared to the UASB reactor without stripper (COD reduction: 92%; methane yield: 0.21m(3)CH(4)/kg COD reduced; OLR: 13.6kg CODm(-3)day(-1); HRT: 16h). The improved performance was due to the reduction of total ammonia nitrogen (TAN) and free ammonia nitrogen (FAN) in the range of 75-95% and 80-95%, respectively by the use of stripper. G/L (air flow rate/poultry leachate flow rate) in the range of 60-70 and HRT in the range of 7-9min are found to be optimum parameters for the operation of the stripper.  相似文献   
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High-quality solution NMR structures of three homeodomains from human proteins ALX4, ZHX1 and CASP8AP2 were solved. These domains were chosen as targets of a biomedical theme project pursued by the Northeast Structural Genomics Consortium. This project focuses on increasing the structural coverage of human proteins associated with cancer.  相似文献   
64.
Anomalous action of human acetylcholinesterase (hAChE) in Alzheimer’s disease (AD) was restrained by various AChE inhibitors, of which the specific and potent lead candidate Donepezil is used for treating the disease AD. Besides the specificity, the observed undesirable side effects caused by Donepezil invoked the quest for new lead molecules with the increased potency and specificity for AChE. The present study elucidates the potency of six 1N-methyl-1S-methyl-2-nitroethylene (NMSM) derivatives to form a specific interaction with the peripheral anionic site and catalytic anionic subsite residues of hAChE. The NMSMs were prepared in good yield from 1,1-di(methylsulfanyl)-2-nitroethylene and primary amine (or) amino acid esters. In silico interaction analysis reveals specific and potent interactions between hAChE and selected ligand molecules. The site-specific interactions formed between these molecules also results in a conformational change in the orientation of active site residues of hAChE, which prevents them from being accessed by beta-amyloid protein (Aβ), which is a causative agent for amyloid plaque formation and acetylcholine (ACh). In silico interaction analysis between the ligand-bounded hAChE with Aß and ACh confirms this observation. The variation in the conformation of hAChE associated with the decreased ability of Aβ and ACh to access the respective functional residues of hAChE induced by the novel NMSMs favors their selection for in vivo analysis to present themselves as new members of hAChE inhibitors.  相似文献   
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The luminal surface of mammalian urothelium is covered with numerous plaques (also known as the asymmetric unit membrane or AUM) composed of semi-crystalline, hexagonal arrays of 12-nm protein particles. Despite the presumed importance of these plaques in stabilizing the urothelial surface during bladder distention, relatively little is known about their protein composition. Using a mouse mAb, AE31, we have identified a 27-kD protein that is urothelium-specific and is differentially expressed in superficial umbrella cells. This protein (pI approximately 5.8) partitions into the detergent phase during Triton X-114 phase separation. Pulse-chase experiments using cultured bovine urothelial cells showed that this protein is synthesized as a 32-kD precursor that is processed through a 30-kD intermediate, to the mature 27-kD form. In cytoplasmic vesicles containing immature AUM, the AE31 epitope is detected in patches on the cytoplasmic side, but in mature, apical AUM it is detected exclusively on the luminal side. This suggests an unusual translocation of the AE31 epitope during AUM maturation; more data are required, however, to substantiate this interpretation. Immunoaffinity purification of the 27-kD protein results in the copurification in approximately molar ratio of a 15-kD protein, as well as a small and variable amount of a 47-kD protein. Immunoblotting data indicate that these three proteins are immunologically distinguishable. This copurified 15-kD protein is relative basic (pI approximately 8.0). Like the 27-kD protein, it is urothelium-specific and is present mainly in the umbrella cells. Together, our data indicate that a 27-kD protein is urothelial plaque-associated (uroplakin I). Based on complex formation data, we provisionally name the 15-kD protein uroplakin II; additional data will be required to determine whether this and the 47-kD protein are integral parts of AUM. The identification of these AUM-associated and -related proteins, plus the availability of a culture system capable of synthesizing and processing some of these molecules, offer new opportunities for studying the detailed structure, assembly, and function of asymmetrical unit membrane.  相似文献   
67.
Barley plants (Hordeum vulgare L.) received foliar applications of 10?4 M gibberellic acid (GA3) and Kinetin (KN) individually and in combination at one or more of three growth stages: flag leaf appearance (I), ear emergence (II), and the first stage of senescence initiation in the flag leaf (III). Both plant growth regulators (PGR) hastened onset of senescence when sprayed at Stage I and/or Stage II. Treatment at Stage III, either alone or in combination with treatments at the other stages, tended to postpone senescence. Yield components also showed stage-dependent response: Stage I treatment increased the formation of total and bearing tillers, and Stage III treatment improved grain number and weight. However, while GA3 proved more effective than KN, the two together acted antagonistically.  相似文献   
68.

Background

Chronic obstructive pulmonary disease (COPD) is associated with a two-to-five fold increase in the risk of coronary artery disease independent of shared risk factors. This association is hypothesized to be mediated by systemic inflammation but this link has not been established.

Methods

We included 300 participants enrolled in the SPIROMICS cohort, 75 each of lifetime non-smokers, smokers without airflow obstruction, mild-moderate COPD, and severe-very severe COPD. We quantified emphysema and airway disease on computed tomography, characterized visual emphysema subtypes (centrilobular and paraseptal) and airway disease, and used the Weston visual score to quantify coronary artery calcification (CAC). We used the Sobel test to determine whether markers of systemic inflammation mediated a link between spirometric and radiographic features of COPD and CAC.

Results

FEV1/FVC but not quantitative emphysema or airway wall thickening was associated with CAC (p?=?0.036), after adjustment for demographics, diabetes mellitus, hypertension, statin use, and CT scanner type. To explain this discordance, we examined visual subtypes of emphysema and airway disease, and found that centrilobular emphysema but not paraseptal emphysema or bronchial thickening was independently associated with CAC (p?=?0.019). MMP3, VCAM1, CXCL5 and CXCL9 mediated 8, 8, 7 and 16% of the association between FEV1/FVC and CAC, respectively. Similar biomarkers partially mediated the association between centrilobular emphysema and CAC.

Conclusions

The association between airflow obstruction and coronary calcification is driven primarily by the centrilobular subtype of emphysema, and is linked through bioactive molecules implicated in the pathogenesis of atherosclerosis.

Trial Registration

ClinicalTrials.gov: Identifier: NCT01969344.
  相似文献   
69.
Summary A dephthalylation step utilizing a novel enzyme, o-phthalyl amidase, was developed. This step was part of a potentially new large scale synthetic route for a novel beta-lactam antibiotic Loracarbef. The enzyme was isolated from the organism Xanthobacter agilis. Purification of the enzyme to near homogeneity was accomplished by a 3-step procedure. Studies indicated that the phthalimido group can be opened chemically to generate the o-phthalyl derivative. This enzyme then can remove the phthalyl group from o-phthalylated amides. Optimization of the process was achieved by combining these two hydrolysis steps. Conversion yields of 85–97.8% (mol/mol) were obtained from reactions at substrate concentrations of 5–10% (w/v).  相似文献   
70.
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