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111.
Ismail Celik Yasin Tuluce Ismail Isik 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):219-226
In the present study, the influence of subchronic effects of two plant growth regulators (PGRs) [Abcisic acid (ABA) and Gibberellic acid (GA3)] on antioxidant defense systems [reduced glutathione (GSH), glutathione reductase (GR), superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT)] and lipid peroxidation level (malondialdehyde = MDA) in various tissues of the rat were investigated during treatment as a drinking water model. 75 ppm of ABA and GA3 in drinking water were continuously administered orally to rats (Sprague-Dawley albino) ad libitum for 50 days. The PGRs treatments caused different effects on the antioxidant defense systems and MDA content of dosed rats compared to controls. The lipid peroxidation end product MDA significantly increased in the lungs, heart and kidney of rats treated with GA3 without significant change in the spleen. ABA caused also a significant increase in MDA content in the spleen, lungs, heart and kidney. The GSH levels were significantly depleted in the spleen, lungs and stomach of rats treated with ABA without any change in the tissues of rats treated with GA3 except the kidney where it increased. Antioxidant enzyme activities such as SOD significantly increased in the lungs and stomach and decreased in the spleen and heart tissues of rats treated with GA3. Meanwhile, SOD significantly decreased in the spleen, heart and kidney and increased in the lungs of rats treated with ABA. While CAT activity significantly decreased in the lungs of rats treated with GA3, a significant increase occurred in the heart of rats treated with both PGRs. On the other hand, the ancillary enzyme GR activity in the tissues were either significantly depleted or not changed with PGRs treatment. The drug metabolizing enzyme GST activity significantly decreased in the lungs of rats treated with ABA but increased in the stomach of rats treated with both PGRs.As a conclusion, the rats resisted oxidative stress via the antioxidant mechanism. But the antioxidant mechanism could not prevent the increases in lipid peroxidation in rat's tissues. This data, along with changes, suggests that PGRs produced substantial systemic organ toxicity in the spleen, lungs, stomach, heart and kidney during a 50-day period of subchronic exposure. 相似文献
112.
Karakas Fatma Pehlivan Turker Arzu Ucar 《In vitro cellular & developmental biology. Plant》2021,57(6):987-997
In Vitro Cellular & Developmental Biology - Plant - Astragalus brachypterus Fischer (milkvetch) is a perennial medicinal plant in the family Fabaceae. Astragalus species have been utilized as... 相似文献
113.
Budama-Kilinc Yasemin Kecel-Gunduz Serda Cakir-Koc Rabia Aslan Bahar Bicak Bilge Kokcu Yagmur Ozel Aysen E. Akyuz Sevim 《International journal of peptide research and therapeutics》2021,27(3):2015-2028
International Journal of Peptide Research and Therapeutics - The aim of the current study was to design a drug delivery nano-system of natural growth-modulating peptide known as GHK that naturally... 相似文献
114.
The chemical composition of the essential oils of Eryngium campestre, E. thorifolium, and E. creticum (Apiaceae), growing in the Aegean region of Turkey (Mount Sandras, Denizli), was determined by direct thermal desorption (DTD)-GC/MS analyses. A total of 49 components were identified in the oils, α-pinene and hexanal being the major compounds. The three essential oils were also tested for their inhibitory activity of nine different methicillin-resistant Staphylococcus aureus (MRSA) strains by the agar disc diffusion method. The anti-MRSA activity of E. thorifolium oil, the most active of the three oils, was comparable with those of the reference antibiotic vancomycin and oregano oil, although somewhat lower. 相似文献
115.
Suey van Baarle Ilkay Nazli Celik Karan Gautam Kaval Marc Bramkamp Leendert W. Hamoen Sven Halbedel 《Journal of bacteriology》2013,195(5):1012-1021
DivIVA proteins are curvature-sensitive membrane binding proteins that recruit other proteins to the poles and the division septum. They consist of a conserved N-terminal lipid binding domain fused to a less conserved C-terminal domain. DivIVA homologues interact with different proteins involved in cell division, chromosome segregation, genetic competence, or cell wall synthesis. It is unknown how DivIVA interacts with these proteins, and we used the interaction of Bacillus subtilis DivIVA with MinJ and RacA to investigate this. MinJ is a transmembrane protein controlling division site selection, and the DNA-binding protein RacA is crucial for chromosome segregation during sporulation. Initial bacterial two-hybrid experiments revealed that the C terminus of DivIVA appears to be important for recruiting both proteins. However, the interpretation of these results is limited since it appeared that C-terminal truncations also interfere with DivIVA oligomerization. Therefore, a chimera approach was followed, making use of the fact that Listeria monocytogenes DivIVA shows normal polar localization but is not biologically active when expressed in B. subtilis. Complementation experiments with different chimeras of B. subtilis and L. monocytogenes DivIVA suggest that MinJ and RacA bind to separate DivIVA domains. Fluorescence microscopy of green fluorescent protein-tagged RacA and MinJ corroborated this conclusion and suggests that MinJ recruitment operates via the N-terminal lipid binding domain, whereas RacA interacts with the C-terminal domain. We speculate that this difference is related to the cellular compartments in which MinJ and RacA are active: the cell membrane and the cytoplasm, respectively. 相似文献
116.
Sevim Çiftçi Yegin Fatmagül Yur Ebubekir Ceylan 《The Journal of membrane biology》2013,246(8):621-626
This study was conducted with the purpose of researching the effect of lycopene application on lipoprotein, paraoxonase (PON) and cytokines that are projected to be used in the diagnosis and treatment of diabetes by making experimental diabetes. At the end of a 1-month trial period, under ether anesthesia with jelly tubes, blood samples were taken from rat hearts. Blood samples were centrifuged and serum was obtained. From the serum samples, HbA1c, paraoxonase activity, lipoprotein levels and cytokines were determined. HbA1c levels and PON activity were found to be p < 0.001. At the triglyceride level, with regard to the control group, in all the groups a significant rise occurred (p ≤ 0.001). At the cholesterol level, with regard to the control group, a decline was observed in the other groups (p < 0.05). At the VLDL level, with regard to the control group, a significant rise was observed in the other groups (p < 0.05). At the HDL (p < 0.001) and LDL (p < 0.05) levels, with regard to the control group, a significant decline was observed in the other groups. At the TNF-α, IL-2, IL-6 and IL-10 levels no difference was found (p > 0.05). Experimental diabetes models have an important place in analyzing diabetes complications and determining treatment approaches. 相似文献
117.
Oguz Ozturk Emel Canbay Ozlem T. Kahraman M. Fatih Seyhan Fatih Aydogan Varol Celik Cihan Uras 《Molecular biology reports》2013,40(2):1813-1818
Although HER2/PTEN pathway is commonly disrupted in cancer, association of HER2 and PTEN polymorphisms with breast cancer (BC) remains controversial. We investigated the HER2 Ile655 Val and PTEN IVS4 polymorphisms in patients with BC in Turkish population. HER2 Ile655Val (rs 1136201) and PTEN IVS4 (rs 3830675) polymorphisms were determined using polymerase chain reaction-based restriction fragment length polymorphism (PCR–RFLP) in blood samples of 118 BC patients and 118 age-matched healthy controls. We found that the frequency of the Ile/Val genotype of HER2 Ile655Val gene was significantly higher in BC patients (p < 0.009; OR: 1,983 95 % CI: 1.181—3.328). The presence of ATCTT insertion (+/+) genotype at downstream of exon 4 in intron 4 of PTEN IVS4 gene was also associated with 1.83 fold decreased risk of BC development (p < 0.033; OR: 1.83, 95 % CI: 1.11—3.03). Analysis on clinico-pathological parameters showed neither HER2 Ile655Val nor PTEN IVS4 genotypes were not associated with any of the variables (p > 0.05).In conclusion, our findings suggest that the Ile/Val genotype of HER2 and ATCTT insertion (+/+) genotype of PTEN IVS4 gene may play an important role as genetic markers for breast cancer risk, but both genes genotypes may not be useful for predicting tumor prognosis in Turkish population. 相似文献
118.
Julia Koehler Leman Ralf Mueller Mert Karakas Nils Woetzel Jens Meiler 《Proteins》2013,81(7):1127-1140
Prediction of transmembrane spans and secondary structure from the protein sequence is generally the first step in the structural characterization of (membrane) proteins. Preference of a stretch of amino acids in a protein to form secondary structure and being placed in the membrane are correlated. Nevertheless, current methods predict either secondary structure or individual transmembrane states. We introduce a method that simultaneously predicts the secondary structure and transmembrane spans from the protein sequence. This approach not only eliminates the necessity to create a consensus prediction from possibly contradicting outputs of several predictors but bears the potential to predict conformational switches, i.e., sequence regions that have a high probability to change for example from a coil conformation in solution to an α‐helical transmembrane state. An artificial neural network was trained on databases of 177 membrane proteins and 6048 soluble proteins. The output is a 3 × 3 dimensional probability matrix for each residue in the sequence that combines three secondary structure types (helix, strand, coil) and three environment types (membrane core, interface, solution). The prediction accuracies are 70.3% for nine possible states, 73.2% for three‐state secondary structure prediction, and 94.8% for three‐state transmembrane span prediction. These accuracies are comparable to state‐of‐the‐art predictors of secondary structure (e.g., Psipred) or transmembrane placement (e.g., OCTOPUS). The method is available as web server and for download at www.meilerlab.org . Proteins 2013; 81:1127–1140. © 2013 Wiley Periodicals, Inc. 相似文献
119.
Simone Carradori Celeste De Monte Melissa D’Ascenzio Daniela Secci Gulsah Celik Mariangela Ceruso Daniela Vullo Andrea Scozzafava Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2013,23(24):6759-6763
Salen and tetrahydrosalen derivatives possess metal-chelating properties and have been used as ligands in organic synthesis and as scaffolds for developing therapeutic agents. Fourteen such compounds were synthesized in order to explore their ability to inhibit the zinc enzyme carbonic anhydrase (CA, EC 4.2.1.1). Human (h) isoforms hCA I, hCA II, hCA IX and hCA XII were included in the investigation. Several aliphatic and aromatic spacers were introduced between the two chelating groups from salen/tetrahydrosalen in order to explore a diverse chemical space for designing CA inhibitors, which incorporate both phenol and polyamine fragments in their molecule. Some of these compounds showed CA inhibitory activity in the low micromolar–nanomolar range and a pronounced selectivity for inhibiting an isoform over-expressed in hypoxic tumors, hCA XII, over hCA I, II and IX. 相似文献
120.
The occurrence of Sciadicleithrum variabilum on the gills of discus Symphysodon aequifasciatus larvae 7 days after hatching is reported for the first time. This suggests that altricial larvae are susceptible to Monogenea following gill differentiation and before complete yolk resorption. 相似文献