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61.
Mycobacterium avium subsp. paratuberculosis (MAP) causes major problem in a wide range of animal species. In ruminant livestock including cattle, it causes a chronic disease called Johne’s disease, or paratuberculosis (pTB) which is currently considered as potential zoonosis, causing Crohn’s disease in humans. MAP infection susceptibility is suspected to be controlled by host genetics. Thus, selecting individuals according to their genetic structure could help to obtain bovine populations that are increasingly resistant to MAP infection. The aim of the present work was to investigate the association between toll-like receptor (TLR) \({ 1}\) (+1380 G/A), TLR1 (+1446 C/A), TLR4 (+10 C/T), TLR9 (+1310 G/A) and solute carrier family 11 member 1 (SLC11A1) (+1066 C/G) mutations and MAP infection status in 813 cattle comprising East Anatolian Red crossbred, Anatolian Black crossbred and Holstein breed. TLR1 (+1380 G/A) mutation showed an association with bovine MAP (\(P\!<\!0.05\)). For the TLR1 (+1380 G/A) locus, the odds ratio for AG and AA genotypes versus GG genotypes were 2.31 (1.24–4.30; 95% confidence interval (CI)) and 0<0.001 (<0.001 to >999.999; 95% CI) which indicated that a proportion of AG homozygote was significantly higher in pTB-affected animals as compared with the control. General linear model analysis demonstrated higher MAP antibody response in TLR1 (+1380 AG) genotype as compared with TLR1 (+1380 GG) (\(P\!<\! 0.0001\)). Present findings suggest that selection against TLR1 (+1380 G/A) may reduce the risk of pTB in bovine herds.  相似文献   
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63.
Tumor suppressor protein p53 induces cell cycle arrest and apoptotic cell death in response to various cellular stresses thereby preventing cancer development. Activation and stabilization of p53 through small organic molecules is, therefore, an attractive approach for the treatment of cancers retaining wild-type p53. In this context, a series of nineteen chalcones with various substitution patterns of functional groups including chloro, fluoro, methoxy, nitro, benzyloxy, 4-methyl benzyloxy was prepared using Claisen-Schmidt condensation. The compounds were characterized using NMR, HRMS, IR and melting points. Evaluation of synthesized compounds against human colorectal (HCT116) and breast (CAL-51) cancer cell lines revealed potent antiproliferative activities. Nine compounds displayed GI50 values in the low micromolar to submicromolar range; for example (E)-1-phenyl-3-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (SSE14108) showed GI50 of 0.473 ± 0.043 µM against HCT116 cells. Further analysis of these compounds revealed that (E)-3-(4-chlorophenyl)-1-phenylprop-2-en-1-one (SSE14105) and (E)-3-(4-methoxyphenyl)-1-phenylprop-2-en-1-one (SSE14106) caused rapid (4 and 8-h post-treatment) accumulation of p53 in HCT116 cells similar to its induction by positive control, Nutlin-3. Such activities were absent in 3-(4-methoxyphenyl)propiophenone (SSE14106H2) demonstrating the importance of conjugated ketone for antiproliferative and p53 stabilizing activity of the chalcones. We further evaluated p53 levels in the presence of cycloheximide (CHX) and the results showed that the p53 stabilization was regulated at post-translational level through blockage of its degradation. These chalcones can, therefore, act as fragment leads for further structure optimization to obtain more potent p53 stabilizing agents with enhanced anti-proliferative activities.  相似文献   
64.
The present study describes efficient and facile syntheses of varyingly substituted 3-thioaurones from the corresponding 3-oxoaurones using Lawesson’s reagent and phosphorous pentasulfide. In comparison, the latter methodology was proved more convenient, giving higher yields and required short and simple methodology. The structures of synthetic compounds were unambiguously elucidated by IR, MS and NMR spectroscopy. All synthetic compounds were screened for their inhibitory potential against in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Molecular docking studies were also performed in order to examine their binding interactions with AChE and BChE human proteins. Both studies revealed that some of these compounds were found to be good inhibitors against AChE and BChE.  相似文献   
65.
Current study aimed at exploring the diversity of bacterial endophytes with Boswellia sacra and their role in copper (Cu) stress to tomato plants. Bacterial endophytes were belonged to Bacillus, Rhizobium and Paenibacillus, which were screened against Cu (0–10?mM) stress to dwarf and normal rice seeds. Among strains, Bacillus amyloliquefaciens BSL16 showed significantly higher bioremediation potential by accumulating high Cu and promoting growth of rice seeds. B. amyloliquefaciens BSL16 significantly increased growth of tomato plants during 2.5?mM Cu stress. Active colonization of BSL16 reduced the accumulation of Cu in leaf, shoot, and root, and in parallel up-regulated total protein contents in leaf and stem. Glutathione peroxidase and reduced glutathione contents were significantly higher and lipid peroxidation was lower in endophyte-treated tomato plants as compared to Cu treatment. The current results conclude that application of metal bio-accumulating bacteria can help in improving the plant growth of tomato plants during Cu stress.  相似文献   
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67.
Adipokines and ghrelin play role in insulin resistance, the key pathophysiological abnormality in patients with nonalcoholic fatty liver diseases. In the present study, relationship between nonalcoholic steatohepatitis (NASH) and serum adipokine and ghrelin levels was investigated. Thirty seven patients with biopsy-proven NASH and 25 age- and sex-matched controls were enrolled. Ten of NASH patients (27%) had diabetes mellitus (n = 5) or impaired glucose tolerance (n = 5). Body mass index (BMI) was less than 30 kg/m(2) in 67.6% of patients, while in the remaining 32.4% it was more than 30 kg/m(2). Serum adiponectin, leptin, TNF-alpha, and ghrelin were determined. Serum leptin (15.49 +/- 4.84 vs 10.31 +/- 2.53) and TNF-alpha (12.1 +/- 2.7 vs 10.31 +/- 2.56) levels were significantly higher in the NASH group compared to in the control group (P < .001 for each). Nevertheless, adiponectin (11.1 +/- 2.1 vs 17.3 +/- 2.8) and ghrelin (6.46 +/- 1.1 vs 7.8 +/- 1.1) levels were lower in the NASH group than in the control group (P < .001 for each). Serum levels of the adipokines and ghrelin, however, were comparable in the subgroups of patients regardless of whether BMI was < 30 or > 30 or glucose tolerance was impaired or not (P > .05). Additionally, neither adipokines nor ghrelin was correlated with histopathological grade and stage (P > .05). In conclusion; there is a significant relationship between NASH and adipokines and ghrelin independent from BMI and status of the glucose metabolism. These cytokines that appear to have role in the pathogenesis of NASH, however, do not have any effect upon the severity of the histopathology.  相似文献   
68.
Itch is a ubiquitin ligase that has been implicated in the regulation of a number of cellular processes. We previously have identified Itch as a binding partner for the endocytic protein Endophilin and found it to be localized to endosomes. Using affinity purification coupled to mass spectrometry, we have now identified the ubiquitin-protease FAM/USP9X as a binding partner of Itch. The association between Itch and FAM/USP9X was confirmed in vitro by glutathione S-transferase pulldown and in vivo through coimmunoprecipation. Itch and FAM partially colocalize in COS-7 cells at the trans-Golgi network and in peripheral vesicles. We mapped the FAM-binding domain on Itch to the WW domains, a region known to be involved in substrate recognition. However, transient overexpression of FAM/USP9X resulted in the deubiquitylation of Itch. Moreover, we show that Itch auto-ubiquitylation leads to its degradation in the proteasome. By examining the amounts of Itch and FAM in various cell lines and rat tissues, a positive correlation was found in the expression of both proteins. This observation suggests that the levels of FAM expression could have an influence on Itch in cells. Experimental decrease in FAM levels by RNA interference leads to a significant reduction in intracellular levels of endogenous Itch, which can be prevented by treatment with the proteasome inhibitor lactacystin. Accordingly, overexpression of FAM/USP9X resulted in a marked increase in endogenous Itch levels. These results demonstrate an intriguing interplay between a ubiquitin ligase and a ubiquitin protease, based on direct interaction between the two proteins.  相似文献   
69.
The p53 tumor suppressor plays a key role in maintaining genomic stability and protection against malignant transformation. MDM2 and MDMX are both p53-binding proteins that regulate p53 stability and activity. Recent development of the MDM2 inhibitor Nutlin 3 has greatly facilitated functional analysis of MDM2-p53 binding. We found that although MDMX is homologous to MDM2 and binds to the same region on p53 N terminus, Nutlin does not disrupt p53-MDMX interaction. The ability of Nutlin to activate p53 is compromised in tumor cells overexpressing MDMX. Combination of Nutlin with MDMX siRNA resulted in synergistic activation of p53 and growth arrest. These results suggest that MDMX is also a valid target for p53 activation in tumor cells. Development of novel compounds that are MDMX-specific or optimized for dual-inhibition of MDM2 and MDMX are necessary to achieve full activation of p53 in tumor cells.  相似文献   
70.
The ability of Fe3O4 Fenton-like reaction to produce glucose from lignocellulosic biomass was investigated. Fe3O4 magnetite nanoparticles were chemically synthesized from iron salts (a mixture of 1 M FeCl2 and 2M FeCl3) using an ammonia solution (30% NH4OH). The synthesized Fe3O4 nanoparticles were further characterized by X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, scanning electron microscopy, and transmission electron microscopy. Reed stems and rice straw biomasses pretreated with optimized Fenton-like reagents (Fe3O4 and H2O2) increased glucose production by 177 and 87%, respectively, compared to the control without the catalysts.  相似文献   
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