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71.
Hatice Yildirim Fatma Bahar Sunay Selma Sinan Feray Köçkar 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1583-1590
Increases in the risk of infections and malignancy due to immune suppressive therapies of inflammatory bowel diseases (IBDs) have led the researchers to focus on more nontoxic and acceptable natural products like curcumin. Here we investigate whether prophylactic and therapeutic application of the curcumin alters the enzyme activities of paraoxonase (PON), carbonic anhydrase (CA), glucose-6-phosphate dehydrogenase (G6PD) and cytosolic β-glucosidase in dextran sulphate sodium (DSS)-induced ulcerative colitis mice. Prophylactic application of curcumin resulted in higher MPO activity, less body weight loss and longer colon lengths compared to therapeutic group indicating preventive role of curcumin in IBDs. DSS-induced decrease in liver and serum PON activities were completely recovered by prophylactic administration of curcumin. DSS-induced reduction in liver cytosolic β-glucosidase activity was not affected by curcumin neither in the prophylactic group nor in the therapeutic group. Erythrocyte CA activity was significantly increased in curcumin groups, however no remarkable change in G6PD activity was observed. 相似文献
72.
Dilek Nartop Birtane Demirel Murat Güle Elvan Hasanolu
zkan Nurdan Kurnaz Yetim Nuren Sar Seluk eker Hatice
ütcü Güleray Aar 《Journal of biochemical and molecular toxicology》2020,34(2)
New polymeric microspheres containing azomethine ( 1a ‐ 1c and 2a ‐ 2c ) were synthesized by condensation to compare the enzymatic properties of the enzyme glucose oxidase (GOx) and to investigate antimutagenic and antimicrobial activities. The polymeric microspheres were characterized by elemental analysis, infrared spectra (FT‐IR), proton nuclear magnetic resonance spectra, thermal gravimetric analysis, and scanning electron microscopy analysis. The catalytic activity of the glucose oxidase enzyme follows Michaelis‐Menten kinetics. Influence of temperature, reusability, and storage capacity of the free and immobilized glucose oxidase enzyme were investigated. It is determined that immobilized enzymes exhibit good storage stability and reusability. After immobilization of GOx in polymeric supports, the thermal stability of the enzyme increased and the maximum reaction rate (Vmax) decreased. The activity of the immobilized enzymes was preserved even after 5 months. The antibacterial and antifungal activity of the polymeric microspheres were evaluated by well‐diffusion method against some selected pathogenic microorganisms. The antimutagenic properties of all compounds were also examined against sodium azide in human lymphocyte cells by micronuclei and sister chromatid exchange tests. 相似文献
73.
Leonid Teytelman Bilge ?zayd?n Oliver Zill Philippe Lefran?ois Michael Snyder Jasper Rine Michael B. Eisen 《PloS one》2009,4(8)
Chromatin has an impact on recombination, repair, replication, and evolution of DNA. Here we report that chromatin structure also affects laboratory DNA manipulation in ways that distort the results of chromatin immunoprecipitation (ChIP) experiments. We initially discovered this effect at the Saccharomyces cerevisiae HMR locus, where we found that silenced chromatin was refractory to shearing, relative to euchromatin. Using input samples from ChIP-Seq studies, we detected a similar bias throughout the heterochromatic portions of the yeast genome. We also observed significant chromatin-related effects at telomeres, protein binding sites, and genes, reflected in the variation of input-Seq coverage. Experimental tests of candidate regions showed that chromatin influenced shearing at some loci, and that chromatin could also lead to enriched or depleted DNA levels in prepared samples, independently of shearing effects. Our results suggested that assays relying on immunoprecipitation of chromatin will be biased by intrinsic differences between regions packaged into different chromatin structures - biases which have been largely ignored to date. These results established the pervasiveness of this bias genome-wide, and suggested that this bias can be used to detect differences in chromatin structures across the genome. 相似文献
74.
Synthetic dyes are extensively used in textile dyeing, paper printing, color photography, and the pharmaceutical, food, cosmetic, and leather industries. Most synthetic dyes are toxic and highly resistant to removal due to their complex chemical structures. There is a need for investigation of the biological treatment of synthetic dyes at a low cost and in the shortest possible time; synthetic dyes are used especially in the dye and textile industries and are an important polluting agent in the wastewater dumped into the environment by these industries. White rot fungus contains a variety of extracellular enzymes, and these enzymes are used for biological degradation of organic matter. The aim of the present work is to evaluate removal of the textile dye Turquoise Blue HFG by Coprinus plicatilis. Coprinus plicatilis was able to enzymatically decolorize 100% of the dye (dye concentration 10.0 and 25.0 mg L?1). Ultraviolet–visible (UV-vis) spectrophotometric analyses, before and after decolorization, suggest that decolorization was due to biodegradation. There was an attempt to identify metabolites with Fourier transform infrared (FT-IR) spectroscopy and gas chromatography–mass spectrometry (GC-MS) at the end of the decolorization process. These results indicate that the samples did not include any detectable metabolite. Therefore, this fungus can be used as an economical and eco-friendly tool to minimize the pollution by industries to a significant extent. 相似文献
75.
In order to detect and identify the most toxic Bacillus thuringiensis strains against pests, we isolated a B. thuringiensis strain (Bn1) from Balaninus nucum (Coleoptera: Curculionidae), the most damaging hazelnut pest. Bn1 was characterized via morphological, biochemical, and molecular techniques. The isolate was serotyped, and the results showed that Bn1 was the B. thuringiensis serovar, kurstaki (H3abc). The scanning electron microscopy indicated that Bn1 has crystals with cubic and bipyramidal shapes. The Polymerase Chain Reactions (PCRs) revealed the presence of the cry1 and cry2 genes. The presence of Cry1 and Cry2 proteins in the Bn1 isolate was confirmed via SDS-PAGE, at approximately 130 kDa and 65 kDa, respectively. The bioassays conducted to determine the insecticidal activity of the Bn1 isolate were conducted with four distinct insects, using spore-crystal mixtures. We noted that Bn1 has higher toxicity as compared with the standard B. thuringiensis subsp. kurstaki (HD-1). The highest observed mortality was 90% against Malacosoma neustria and Lymantria dispar larvae. Our results show that the B. thuringiensis isolate (Bn1) may prove valuable as a significant microbial control agent against lepidopteran pests. 相似文献
76.
M Jung A Weigert M Tausendschön J Mora B Oren A Sola G Hotter T Muta B Brüne 《Molecular and cellular biology》2012,32(19):3938-3948
Tumor cell-derived factors, such as interleukin 10 (IL-10), polarize macrophages toward a regulatory M2 phenotype, characterized by the expression of anti-inflammatory cytokines and protumorigenic mediators. Here we explored molecular mechanisms allowing IL-10 to upregulate the protumorigenic protein NGAL in primary human macrophages. Reporter assays of full-length or deletion constructs of the NGAL promoter provided evidence that NGAL production is STAT3 dependent, activated downstream of the IL-10-Janus kinase (Jak) axis, as well as being C/EBPβ dependent. The involvement of STAT3 and C/EBPβ was shown by chromatin immunoprecipitation (ChIP) and ChIP-Western analysis, as well as decoy oligonucleotides scavenging both STAT3 and C/EBPβ in human macrophages. Furthermore, the production of NGAL in macrophages in response to IL-10 induces cellular growth and proliferation of MCF-7 breast cancer cells. We conclude that both STAT3 and C/EBPβ are needed to elicit IL-10-mediated NGAL expression in primary human macrophages. Macrophage-secreted NGAL shapes the protumorigenic macrophage phenotype to promote growth of MCF-7 breast cancer cells. Our data point to a macrophage-dependent IL-10-STAT3-NGAL axis that might contribute to tumor progression. 相似文献
77.
Tryptophan as a circulating precursor of serotonin (5-HT) may suppress food intake and body weight. Tryptophan administration can enhance the generation of reactive oxygen species (ROS) by inducing oxidative pathway in vivo and in vitro. We have examined the effect of repeated tryptophan administration on food consumption, body weight, brain lipid peroxidation and 5-HT immunoreactivity. Tryptophan was given at the dose of 100 mg/kg/24 hr in 0.2 ml saline solution i.p. for 7 days to mice. Control mice received 0.9% NaCL solution at the same manner and volume. Body weights were recorded at the beginning and end of the experiments. Thiobarbituric acid reactive substance (TBARS), the last product of lipid peroxidation, was measured spectrophotometrically. Brain 5-HT levels were determined by the immunohistochemical method. Our findings indicate that the tryptophan suppresses food intake significantly in mice. Body weight decreased and brain TBARS levels increased significantly by repeated tryptophan treatment. Immunohistochemical detection showed that 5-HT levels increased by tryptophan administration. There is a link between increased 5-HT level and oxidative stress by tryptophan administration on brain tissue. Tryptophan at repeated doses should be exercised carefully in clinical practice. 相似文献
78.
The European spruce bark beetle, Dendroctonus micans Kugelann (Coleoptera, Scolytidae), is one of the most serious pests of oriental spruce (Picea orientalis L.) in Turkey. In this study, we investigated bacterial flora of D. micans collected from different populations of the forests of Eastern Black Sea Region of Turkey from 2002 to 2004. Seven different
bacteria were isolated from healthy, diseased and dead specimens based on the color of colony and morphology. According to
morphological, physiological and biochemical properties, metobolic enyzme profile by BIOLOG microtiter plate system, and total
cellular fatty acid profile by Microbial Identification System (MIS), isolates were identified as Micrococcus luteus, Bacillus thuringiensis subsp. morrisoni, Serratia grimesii, Enterobacter cloaceae, Enterobacter intermedius, Streptococcus sp. and Pseudomonas putida. This is the first study on the bacterial flora of D. micans. 相似文献
79.
Heads of sunflower (Helianthus annuus L.) were first biodegraded at 55 degrees C by their microflora. Biodegradation products of sunflower heads (BPSH) were analyzed. They were found to contain 9.77% dry matter, 3.98% total ash, 3.18% crude protein and 5.75% total organic matter. BOD load was determined as 4.80 g/100 g. Subsequently, the effects of BPSH at various concentrations (1.0%, 2.5%, 10% and 100%) on the seed germination and some growth parameters of Phaseolus vulgaris L., Cicer arietinum L. and Triticum vulgare L. were investigated. The percentages of seed germination and germination index of seeds were similar between the control and 1.0% and 2.5% BPSH groups, but these values decreased at higher concentrations. On the other hand, growth of the seedlings gradually increased up to a concentration of 10% BPSH and decreased at 100% concentration. As a result, at concentrations up to 10% the product was found to be beneficial for growth of plants. 相似文献
80.
Recent evidence suggests that non-muscle myosin IIB (NMIIB) contributes to smooth muscle contraction. This study was designed to determine the effects of NMIIB on the cross-bridge cycling rate. The cross-bridge cycling rate was investigated using sinusoidal analysis. Frequency analysis revealed two asymptotes in the Bode plot of the data; and the intersection of the asymptotes (corner frequency) was higher for the B+/− strain (8.73 ± 1.10 Hz vs 16.56 ± 1.26 Hz, P < 0.05), consistent with a higher overall cross-bridge cycling rate in heterozygous NMIIB KO (B+/−) vs WT mice. These results demonstrate that because of their long duty cycle, NMIIB cross-bridges act as an internal load on smooth muscle myosin to decrease the overall cross-bridge cycling rate and muscle Vmax during force maintenance. 相似文献