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51.
In this work, the terbium(III), dysprosium(III), and ytterbium(III) complexes containing 2, 2′-bipyridine (bpy) ligand have been synthesized and characterized using CHN elemental analysis, FT-IR, UV–Vis and 1H-NMR techniques and their binding behavior with human serum albumin (HSA) was studied by UV–Vis, fluorescence and molecular docking examinations. The experimental data indicated that all three lanthanide complexes have high binding affinity to HSA with effective quenching of HSA fluorescence via static mechanism. The binding parameters, the type of interaction, the value of resonance energy transfer, and the binding distance between complexes and HSA were estimated from the analysis of fluorescence measurements and Förster theory. The thermodynamic parameters suggested that van der Waals interactions and hydrogen bonds play an important role in the binding mechanism. While, the energy transfer from HSA molecules to all these complexes occurs with high probability, the order of binding constants (BpyTb > BpyDy > BpyYb) represents the importance of radius of Ln3+ ion in the complex-HSA interaction. The results of molecular docking calculation and competitive experiments assessed site 3 of HSA, located in subdomain IB, as the most probable binding site for these ligands and also indicated the microenvironment residues around the bound mentioned complexes. The computational results kept in good agreement with experimental data.  相似文献   
52.
From a mixture of cis- and trans-Ru(SH)2(dppm)2 (4), formed from reaction of H2S with trans-Ru(H)Cl(dppm)2 (2), a crystal of cis-4 has been isolated and its structure determined by X-ray analysis. The mercapto protons are located within the centrosymmetric structure, although the S-atoms are partially disordered (S–H1.06 Å). The thiolate complexes, trans-Ru(H)SR(dppm)2 (R=Ph, 5a; C6F5, 5b), have been isolated from reaction of trans-2 with 1 equiv. of RSH. trans-Ru(H)SH(dppm)2 (3) has been isolated from reaction of H2S with a mixture of cis- and trans-Ru(H)2(dppm)2 (1). An improved synthetic route for 1 is presented.  相似文献   
53.
Surface-active cellulose films for covalent attachment of bioactive moieties were achieved by codissolution of cellulose with polyamidoamine (PAMAM) dendrimers in an ionic liquid followed by regeneration of the composite as a film. Different generations of PAMAM were used for the formation of cellulose-dendrimer composites, as well as films with the dendrimer covalently bonded to the cellulose by means of the linker 1,3-phenylene diisocyanate. Surface characterization, thermal stability, and utility for immobilization of laccase were determined. The presence of the dendrimer amino groups was confirmed by detailed characterization of the films' surfaces. These modified films exhibit acceptable thermal stability, comparable to that of other regenerated cellulose films, but the number of active functional groups on the surface is much smaller than the theoretical amount expected. Films made with 1,3-phenylene diisocyanate as linker for covalently bound cellulose and dendrimers exhibit a better performance for immobilization of laccase than those prepared by simple mixing of the cellulose and dendrimer. In general, a linear correspondence between the dendrimer generation within the films and the specific activity of immobilized laccase in such films was not observed.  相似文献   
54.
Colorectal cancer (CRC), regardless of standard procedures of treatment and screening, is still considered one of the deadliest cancers in the Western world, and in economically developed Asian countries, especially Iran. The current study was undertaken to investigate whether changes in the level of Cripto-1 (CR-1) expression and KRAS mutations have a cumulative effect on the onset and progression of CRC. Fifty colorectal tissue samples, including 35 colorectal carcinomas with matching adjacent mucosa, and 15 colorectal adenomas, were chosen for analysis. Twenty-five CRC biopsies and 15 adenoma were analyzed for KRAS mutations by DNA sequencing (Sanger sequencing), and all 50 patients (35 CRCs and 15 adenomas) were evaluated by immunohistochemistry for the CR-1 protein expression. The inducible somatic KRAS mutation (G12D) was observed in nine (36%) of CRC patients, and in two (13.3%) of adenoma patients. The CR-1 expression level in both adenomas (P < .05) and carcinomas (P < .001), were significantly different, compared with the matching adjacent mucosa. The intensity of CR-1 staining in adenomas was less than the intensity of staining, detected in the CRCs (P < .001). The G12D KRAS mutation and CR-1 abnormalities are significantly associated as two signature biomarkers with potential clinical characteristics for the detection of CRC development.  相似文献   
55.
AimThe aim of this study was to determine the influence of manual toothbrushes with different bristle stiffness on the abrasivity on eroded and sound human dentin.ResultsWith respect to bristle stiffness there was no statistically significant difference in dentin loss within the EA group. In group A, a statistically significantly higher dentin loss was found for the soft in comparison to the hard bristles. No statistically significant differences were measured between soft/medium and medium/hard toothbrushes. The amount of dentin loss from specimens in the EA group was significantly higher than in the A group.ConclusionsWithin the limitations of this study, the dentin loss in the Abrasion group was higher with soft bristles than with hard ones. This result might have an influence on the toothbrush recommendations for patients with non-carious cervical lesions.  相似文献   
56.
Diabetes mellitus (DM) disease can affect process of apoptosis by increasing oxidative stress, nevertheless exercise and crocin can improve apoptosis; therefore present study aimed to investigate the effect of continued training with crocin on apoptosis markers in liver tissue of diabetic rats. In this experimental study 32 diabetic rats based on fasting glucose divided into four groups of eight rats including: 1) sham, 2) training, 3) crocin, and 4) training with crocin also for investigate the effect of DM induction on apoptosis markers, eight healthy rats assigned in healthy control group. During eight weeks groups 2 and 4 ran 60 minutes on treadmill with intensity of 50–55% maximum speed for three sessions per week and groups 3 and 4 received 25 mg/kg/day crocin peritoneally. Shapiro–Wilk, one-way ANOVA with Tukey’s post-hot tests were used for statistical analysis of data (P ≤ 0.05). DM induction significantly increased Bcl-2 as well as decreased Bax and P52 (P ≤ 0.05) nevertheless training and training with crocin significantly decreased Bcl-2 and increased Bax and P53 (P ≤ 0.05); crocin significantly decreased Bcl-2 and increased P53 (P ≤ 0.05) and training with crocin had higher effect on increase of Bax and P53 compare to training (P ≤ 0.05) also increase of Bax compare to crocin. Although training and crocin alone can improve apoptotic markers in diabetic rats, nevertheless training simultaneously with crocin have better effects than training alone.  相似文献   
57.
Colorado potato beetle (CPB) is the important pest of potato throughout the world. The study showed the effects of vermicompost on nutritional indices, digestive enzyme activities and intermediary metabolism of the larvae and the adults of CPB. Vermicompost affected significantly the efficiency of conversion of ingested food (ECI) and efficiency of conversion of digested food (ECD) in addition to activities of carbohydrases and proteases in both larvae and adults. Amount of total phenol compounds increased in the leaves of the potatoes grown on the soil containing 30% of vermicompost compared to control and it were amended by 15% of vermicompost. In case of intermediary metabolism, activities of aspartate aminotransferase and γ-glutamyl transferase showed no significant differences in the control and the treated larvae, but those were fluctuated upper and lower when 15% of vermicompost was added into growth plots. The amount of low-density lipoproteins (LDL) and high-density lipoproteins (HDL) in the larvae of CPB showed no significant differences among treatments. However, the amounts of LDL, HDL, glycogen and protein of the adults significantly increased using 30% of vermicompost. Results of the current study clearly revealed significant effects on some physiological processes in CPB fed on the plants grown in the different vermicompost treatments.  相似文献   
58.
Resveratrol is a plant polyphenolic compound. Evidence indicates that resveratrol has beneficial effects against aging and neurodegenerative diseases. The goal of our study was in vivo examination of the effects of resveratrol on the abundance of mRNA encoding Brain Derived Neurotrophic Factor (BDNF) in the hippocampus of rat brain. Rats were administrated orally by different doses (2.5–20 mg/kg bwt) of resveratrol for 3, 10 and 30 days. Saline was used as control and 10% ethanol in saline was used as vehicle for resveratrol. Measurement of BDNF mRNA by Real-time RT–PCR showed that levels of the mRNA for BDNF were significantly and dose dependently elevated in the hippocampal tissues of rats. The findings suggest that the neuroprotective effects of resveratrol may be at least partly due to its inducing effects on the expression levels of the BDNF mRNA.  相似文献   
59.
Background: Nowadays, there is an increasing interest in noninvasive methods to diagnose Helicobacter pylori infection. Indeed, they can profitably replace endoscopy in predicting the diagnosis. The stool antigen test for H. pylori is a noninvasive immunoassay to diagnose active infection with this bacterium in human fecal samples. The aim of this study was detection of alkyl hydroperoxide reductase protein (AhpC) antigen by immunoblotting in stool samples for diagnosis of H. pylori. Materials and Methods: Chromosomal DNA from H. pylori was isolated. AhpC gene was amplified by PCR, These amplicons were cloned into pTZ57R/T cloning vector then subcloned into pQE30 expression vector and overexpressed using isopropyl‐beta‐D‐thiogalactopyranoside in E. coli M15. AhpC protein was purified by affinity chromatography. Rabbits were immunized with the purified AhpC protein for the production of antibodies. To determine the accuracy of the test for diagnosing H. pylori infection from stool, we evaluated 84 patients (6–81 years old) using Western blot analysis by rabbit anti‐AhpC antibody. Positive rapid urease test on biopsy samples was considered as the gold standard. Results: AhpC gene was overexpressed, and AhpC protein was purified. Rabbit anti‐AhpC antibody produced after immunization with the purified AhpC protein. By immunoblotting, we detected AhpC protein in the positive stool samples. The test showed a 83.3% sensitivity (95% CI: 69.8–92.5%) and a 91.7% specificity (95% CI: 77.5–98.2). Among the children, the sensitivity was 88.2% (95% CI: 63.6–98.5) and the specificity was 100% (95% CI: 69.2–100); in adults, the sensitivity and specificity were 80.6% (95% CI: 62.5–92.5) and 88.5% (95% CI: 69.8–97.6), respectively. Conclusions: Using of AhpC antigen for diagnosis of H. pylori infection is a useful noninvasive method, accurate in adolescents and children, and can be used for the development of a stool antigen detection kit for H. pylori.  相似文献   
60.
In the past few years, organic–inorganic metal halide ABX3 perovskites (A = Rb, Cs, methylammonium, formamidinium (FA); B = Pb, Sn; X = Cl, Br, I) have rapidly emerged as promising materials for photovoltaic applications. Tuning the film morphology by various deposition techniques and additives is crucial to achieve solar cells with high performance and long‐term stability. In this work, carbon nanoparticles (CNPs) containing functional groups are added to the perovskite precursor solution for fabrication of fluorine‐doped tin oxide/TiO2/perovskite/spiro‐OMeTAD/gold devices. With the addition of CNPs, the perovskite films are thermally more stable, contain larger grains, and become more hydrophobic. NMR experiments provide strong evidence that the functional groups of the CNPs interact with FA cations already in the precursor solution. The fabricated solar cells show a power‐conversion efficiency of 18% and negligible hysteresis.  相似文献   
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