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31.
Idiopathic nephrotic syndrome (INS) is a genetically heterogeneous group of disorders characterized by proteinuria, hypoalbuminemia, and edema. Because it typically results in end-stage kidney disease, the steroid-resistant subtype (SRNS) of INS is especially important when it occurs in children. The present study included 29 affected and 22 normal individuals from 17 SRNS families; genome-wide analysis was performed with Affymetrix 250K SNP arrays followed by homozygosity mapping. A large homozygous stretch on chromosomal region 12p12 was identified in one consanguineous family with two affected siblings. Direct sequencing of protein tyrosine phosphatase receptor type O (PTPRO; also known as glomerular epithelial protein-1 [GLEPP1]) showed homozygous c.2627+1G>T donor splice-site mutation. This mutation causes skipping of the evolutionarily conserved exon 16 (p.Glu854_Trp876del) at the RNA level. Immunohistochemistry with GLEPP1 antibody showed a similar staining pattern in the podocytes of the diseased and control kidney tissues. We used a highly polymorphic intragenic DNA marker-D12S1303-to search for homozygosity in 120 Turkish and 13 non-Turkish individuals in the PodoNet registry. This analysis yielded 17 candidate families, and a distinct homozygous c.2745+1G>A donor splice-site mutation in PTPRO was further identified via DNA sequencing in a second Turkish family. This mutation causes skipping of exon 19, and this introduces a premature stop codon at the very beginning of exon 20 (p.Asn888Lysfs*3) and causes degradation of mRNA via nonsense-mediated decay. Immunohistochemical analysis showed complete absence of immunoreactive PTPRO. Ultrastructural alterations, such as diffuse foot process fusion and extensive microvillus transformation of podocytes, were observed via electron microscopy in both families. The present study introduces mutations in PTPRO as another cause of autosomal-recessive nephrotic syndrome.  相似文献   
32.
This work describes a unique and environmentally friendly approach for creating three-dimensional (3D) organic-inorganic flower shaped hybrid nanostructures called “nanoflower (NF)” by using Umbilicaria decussate (U. decussate) extract and copper ions (Cu2+). U. decussate species were collected from certain place in Antarctic and Turkey and extraction of each species were completed in methanol and water. The U. decussate extracts were used as organic components and Cu2+ acted as inorganic components for formation of U. decussate extracts based hybrid NFs. We rationally used these NFs as novel nanobiocatalyst and antimicrobial agents. These NFs exhibited peroxidase mimic, dye degradation and antimicrobial properties. The NFs were characterized with various techniques. For instance, the morphologies of the NFs were monitored by scanning electron microscope (SEM), presence of elements in the NFs were presented using Energy Dispersive X-Ray Analysis (EDX). Fourier-transform infrared spectroscopy (FT-IR) was used to elucidate corresponding bending and stretching of bonds in the NFs. The NFs acted as effective Fenton agents in the presence of hydrogen peroxide, and we demonstrated their peroxidase-like activity against guaiacol, dye degradation property towards malachite green and antimicrobial activity for Aeromonas hydrophila, Aeromonas sobria, Escherichia coli, Salmonella enterica and Staphylococcus aureus.  相似文献   
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In this study, CoCrMo alloy was oxidized in plasma environment at the temperatures of 600 ℃ to 800 ℃ for 1 h to 5 h with 100% 02 gas and its tribological behavior was investigated. After the plasma oxidizing process, the compound and diffusion layers were formed on the surface. XRD results show that Cr203, a-Co and ε-Co phases diffracted from the modified layers after plasma oxidizing. The untreated and treated CoCrMo samples were subjected to wear tests both in dry and simulated body fluid conditions, and normal loads of 2 N and 10 N were used. For the sliding wear test, alumina balls were used as counter materials. It was observed that the wear resistance of CoCrMo alloy was increased after the plasma oxidizing process. The lowest wear rate was obtained from the samples that were oxidized at 800 ℃ for 5 h. It was detected that both wear environment and load have significant effects on the wear behavior of this alloy, and the wear resistance of oxidized CoCrMo alloy is higher when oxide-based counterface is used. The wear rates of both untreated and plasma oxidized samples increase under high loads.  相似文献   
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The conformational states of two peptide sequences that bind to staphylococcal enterotoxin B are sampled by replica exchange molecular dynamic (REMD) simulations in explicit water. REMD simulations were treated with 52 replicas in the range of 280–501 K for both peptides. The conformational ensembles of both peptides are dominated by random coil, bend and turn structures with a small amount of helical structures for each temperature. In addition, while an insignificant presence of β-bridge structures were observed for both peptides, the β-sheet structure was observed only for peptide 3. The results obtained from simulations at 300 K are consistent with the experimental results obtained from circular dichroism spectroscopy. From the analysis of REMD results, we also calculated hydrophobic and hydrophilic solvent accessible surface areas for both peptides, and it was observed that the hydrophobic segments of the peptides tend to form bend or turn structures. Moreover, the free-energy landscapes of both peptides were obtained by principal component analysis to understand how the secondary structural properties change according to their complex space. From the free-energy analysis, we have found several minima for both peptides at decreased temperature. For these obvious minima of both peptides, it was observed that the random coil, bend and turn structures are still dominant and the helix, β-bridge or β-sheet structures can appear or disappear with respect to minima. On the other hand, when we compare the results of REMD with conventional MD simulations for these peptides, the configurations of peptide 3 might be trapped in energy minima during the conventional MD simulations. Hence, it can be said that the REMD simulations have provided a sufficiently high sampling efficiency.  相似文献   
36.
Paracetamol (PC) is a widely used analgesic and antipyretic drug, but it leads to acute hepatotoxicity at high doses intakes. This study was aimed to investigate the effects of Chrysin (CR) on hepatotoxicity constituted at high doses of PC in rats. Rats were subjected to oral pretreatment of CR (25 and 50 mg/kg b.w.) via feeding needle for 6 days against hepatotoxicity induced by a single dose of PC (500 mg/kg b.w.) administered orally via feeding needles. Although PC increases lipid peroxidation and liver enzyme activities, it has led to reduction of antioxidant enzyme activities. PC induced inflammatory responses by increasing the levels of TNF‐α and IL‐1β. Furthermore, PC caused apoptosis and autophagy by increasing activity of Caspase‐3 and LC3B level. On the other hand, CR therapy significantly regulated these values in rats. This study demonstrated that CR possesses restorative effect against PC‐induced hepatotoxicity by suppressing oxidative stress, inflammation, and apoptotic and autophagic tissue damage.  相似文献   
37.
Pazopanib is a tyrosine kinase inhibitor that is generally used for the treatment of metastatic renal cell cancer and advanced soft tissue sarcoma. It can cause various degrees of hepatotoxicity. Our study aimed to investigate the effect of taxifolin on pazopanib-induced liver toxicity. A total of 18 rats were divided into three groups: the pazopanib (PP), pazopanib plus taxifolin (TPP), and control (C) group. Taxifolin was administered to the TPP (n=6) group with a dose of 50 mg/kg. Distilled water was orally admnistered to the C (n=6) and PP (n=6) groups as a solvent. Subsequently, pazopanib 200 mg/kg was administered to the TPP and PP groups via the stomach. This procedure was repeated once a day for four weeks. Then, all rats were sacrificed, and their livers were removed. Malondialdehyde (MDA), total glutathione (tGSH), total oxidant status (TOS), and total antioxidant status (TAS) levels were evaluated. MDA and TOS levels were higher in the PP group compared with the levels of the other parameters (P<0.001). tGSH and TAS levels were lower in the PP group than in the TPP and C groups (P<0.001), and the aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were higher. Furthermore, liver tissue damage, including hemorrhage, hydropic degeneration, and necrosis was observed in the PP group. Administration of taxifolin before pazopanib significantly improved degenerative changes. Our study demonstrated that the administration of taxifolin is significantly effective in preventing pazopanib-induced hepatotoxicity in rats.  相似文献   
38.
Schiff bases (imines or azomethines) are versatile ligands synthesized from the condensation of amino compounds with active carbonyl groups and used for many pharmaceutical and medicinal applications. In our study, we aimed to determine the cytotoxic, antifungal and larvicidal activities of biologically potent bis-sulfonamide Schiff base derivatives that were re-synthesized by us. For this aim, 16 compounds were re-synthesized and tested for their cytotoxic, antifungal and larvicidal properties. Among this series, compounds A1B2 , A1B4 , A4B2 , A4B3 , and A4B4 were shown to have cytotoxic activity against tested cancer lung cell line (A549). The most potent antifungal activity was observed in compounds A2B1 and A2B2 against all fungi. A1B1 showed the strongest larvicidal effect at all concentrations at the 72nd h (100% mortality). These obtained results demonstrate that these type of bis-substituted compounds might be used as biologically potent pharmacophores against different types of diseases.  相似文献   
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The aims of this study were to clarify the effects of high dietary supplementation with boric acid and borax, called boron (B) compounds, on lipid peroxidation (LPO), antioxidant activity, some vitamin levels, and DNA damage in rats. Thirty Sprague Dawley male rats were divided into three equal groups: the animals in the first group (control) were fed with a standard rodent diet containing 6.4 mg B/kg, and the animals in the experimental group were fed with a standard rodent diet added with a supra-nutritional amount of boric acid and borax (100 mg B/kg) throughout the experimental period of 28 days. The B compounds decreased malondialdehyde (MDA), DNA damage, the protein carbonyl content (PCO) level in blood, and glutathione (GSH) concentration in the liver, Cu–Zn superoxide dismutase (SOD), and catalase (CAT) activity in the kidney. The B compounds increased GSH concentration in blood and the vitamin C level in plasma. Consequently, our results demonstrate that B supplementation (100 mg/kg) in diet decreases LPO, and enhances the antioxidant defense mechanism and vitamin status. There are no differences in oxidant/antioxidant balance and biochemical parameters except for serum vitamin A and liver GSH concentration, between the boron compounds used in this study.  相似文献   
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