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51.
Calprotectin is member of the S-100 protein family with a wide plethora of intra-and extracellular functions. Anticancer activities, antimicrobial effects and being a qualified disease marker are among the compelling features of this protein to be used as a pharmaceutical agent. However, there are several impediments to applications of protein pharmaceuticals including: proteolytic degradation, short circulating half-life, low solubility and immunogenicity. Pegylation is a common bioconjugation polymer capable of overcoming these drawbacks. Recombinant expression and purification of calprotectin along with its pegylation would result in enhanced pharmaco-dynamic and pharmacokinetic properties. Our florescence spectroscopy and far Ultraviolet-optical density results indicate that pegylation altered the physical and structural properties of the calprotectin to become in a more stable and functionally active state. Due to enhanced pharmacodynamic and pharmacokinetic properties of the calprotectin via pegylation, this study would pave the way for better in vitro and in vivo validations of calprotectin applications in medical practice.  相似文献   
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Solution of the nonlinear differential equations for renal network flows are investigated, and conditions are given under which a unique solution to these equations exists.  相似文献   
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Six cultivars and breeding lines of potato (Solanum tuberosum) differing in susceptibility to verticillium wilt caused by Verticillium dahliae were studied with respect to quantitative and qualitative differences in the bacterial flora of their soil and rhizosphere-rhizoplane. Although, no association was observed between the types of bacteria that inhabited the soil or roots of wilt resistant and susceptible cultivars, quantitative differences were evident. These differences provide the first direct evidence that potato genotypes can influence bacterial populations. Bacterial populations were 9–25-fold higher on roots than in the adjacent soil. As the plants aged, the total number of rootcolonizing bacteria increased between 15 and 245%. Pseudomonas spp. were the most abundant microbes in the soil and rhizosphere-rhizoplane. The bacteria antagonistic to V. dahliae in vitro were identified as members of the genera Bacillus, Pseudomonas, Flavobacterium, and Gluconobacter. A statistically significant trend was evident toward the association of antagonistic bacteria with the more resistant potato cultivars.  相似文献   
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Prostate cancer (PCa) is the second most common malignancy and is the fifth leading cause of cancer mortality among men globally. Docetaxel-based therapy remains the first-line treatment for metastatic castration-resistant prostate cancer. However, dose-limiting toxicity including neutropenia, myelosuppression and neurotoxicity is the major reason for docetaxel dose reductions and fewer cycles administered, despite a recent study showing a clear survival benefit with increased total number of docetaxel cycles in PCa patients. Although previous studies have attempted to improve the efficacy and reduce docetaxel toxicity through drug combination, no drug has yet demonstrated improved overall survival in clinical trial, highlighting the challenges of improving the activity of docetaxel monotherapy in PCa. Herein, we identified 15 lethality hits for which inhibition could enhance docetaxel sensitivity in PCa cells via a high-throughput kinome-wide loss-of-function screen. Further drug-gene interactions analyses identified Janus kinase 1 (JAK1) as a viable druggable target with existing experimental inhibitors and FDA-approved drugs. We demonstrated that depletion of endogenous JAK1 enhanced docetaxel-induced apoptosis in PCa cells. Furthermore, inhibition of JAK1/2 by baricitinib and ruxolitinib synergizes docetaxel sensitivity in both androgen receptor (AR)–negative DU145 and PC3 cells, but not in the AR-positive LNCaP cells. In contrast, no synergistic effects were observed in cells treated with JAK2-specific inhibitor, fedratinib, suggesting that the synergistic effects are mainly mediated through JAK1 inhibition. In conclusion, the combination therapy with JAK1 inhibitors and docetaxel could be a useful therapeutic strategy in the treatment of prostate cancers.  相似文献   
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Kumar A  Tyagi NK  Goyal P  Pandey D  Siess W  Kinne RK 《Biochemistry》2007,46(10):2758-2766
Although there is no evidence of significant Na-independent glucose flux in tissues naturally expressing SGLT1, previous kinetic and biophysical studies suggest that sodium/d-glucose cotransporter 1 (hSGLT1) can facilitate sodium-independent d-glucose transport and may contain more than one sugar binding site. In this work, we analyze the kinetic properties and conformational states of isolated hSGLT1 reconstituted in liposomes by transport and fluorescence studies in the absence of sodium. In the transport studies with hSGLT1, significant sodium-independent phlorizin inhibitable alpha-methyl d-glucopyranoside (alpha-MDG) uptake was observed which amounted to approximately 20% of the uptake observed in the presence of a sodium gradient. The apparent affinity constant for alpha-MDG was thereby 3.4 +/- 0.5 mM, a value approximately 10-fold higher than that in the presence of sodium. In the absence of sodium, various sugars significantly decreased the intrinsic Trp fluorescence of hSGLT1 in proteoliposomes exhibiting the following sequence of affinities: alpha-MDG > d-glucose approximately d-galactose > 6-deoxy-d-glucose > 2-deoxy-d-glucose > d-allose. Furthermore, significant protection effects of d-glucose or phlorizin against potassium iodide, acrylamide, or trichloroethanol quenching were observed. To locate the Trps involved in this reaction, we generated mutants in which all Trps were sequentially substituted with Phe. None of the replacements significantly affected sodium-dependent uptake. Uptake in the absence of sodium and typical fluorescence changes depended, however, on the presence of Trp at position 561. This Trp residue is conserved in all known SGLT1 forms (except Vibrio parahaemolyticus SGLT) and all SGLT isoforms in humans (except hSGLT3). If all these data are taken into consideration, it seems that Trp-561 in hSGLT1 forms part of a low-affinity sodium-independent binding and/or translocation site for d-glucose. The rate of sodium-independent translocation via hSGLT1 seems, however, to be tightly regulated in the intact cell by yet unknown factors.  相似文献   
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The aim of this study is to isolate and identify Lactobacillus plantarum isolates from traditional cheese, Kouzeh, and evaluate their antimicrobial activity against some food pathogens. In total, 56 lactic acid bacteria were isolated by morphological and biochemical methods, 12 of which were identified as Lactobacillus plantarum by biochemical method and 11 were confirmed by molecular method. For analyzing the antimicrobial activity of these isolates properly, diffusion method was performed. The isolates were identified by 318 bp band dedicated for L. plantarum. The isolated L. plantarum represented an inhibitory activity against four of the pathogenic bacteria and showed different inhibition halos against each other. The larger halos were observed against Staphylococcus aureus and Staphylococcus epidermidis (15 ± 0.3 and 14.8 ± 0.7 mm, respectively). The inhibition halo of Escherichia coli was smaller than that of other pathogen and some L. plantarum did not show any inhibitory activity against E. coli, which were resistant to antimicrobial compounds produced by L. plantarum. The isolated L. plantarum isolates with the antimicrobial activity in this study had strong probiotic properties. These results indicated the nutritional value of Kouzeh cheese and usage of the isolated isolates as probiotic strains.  相似文献   
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