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991.
Heena Imtiaz Malik Abdul Rouf Mir Minhal Abidi Safia Habib Fahim Halim Khan 《Journal of biomolecular structure & dynamics》2020,38(7):1984-1994
AbstractAutoimmune responses against post-translationally modified antigens are a hallmark of several autoimmune diseases. In this work, we have studied the changes in alpha-2-macroglobulin (α2M) upon modification by peroxynitrite. Furthermore, we have evaluated the immunogenicity of modified α2M in experimental rabbits and rheumatoid arthritis (RA) patients. Peroxynitrite-modified α2M showed disturbed microenvironment and altered aromatic residues under UV and fluorescence studies. Aggregation, reduction in β-sheet content, production of nitrotyrosine and shift in amide I and II bands were observed in the modified α2M by polyacrylamide gel electrophoresis besides CD and FTIR spectroscopic analysis. The exposure of hydrophobic clusters and changes in contact positions were observed in ANS and ThT binding assays. Immunological studies using ELISA showed peroxynitrite-modified α2M as highly immunogenic producing high titre of specific antibodies in immunized rabbits. Cross-reactivity studies revealed the polyspecificity of the elicited antibodies. Direct binding ELISA and competitive inhibition studies confirmed the presence of circulating antibodies in the sera of RA patients having high specificity towards the peroxynitrite-modified α2M as compared to the native α2M. Sera from healthy (normal) human subjects showed lower binding with the native and modified protein. This study confirms that peroxynitrite induces structural modifications in α2M and makes it immunogenic. The presence of neo-antigenic determinants on modified α2M with enhanced binding for circulating autoantibodies in RA patients could offer new possibilities for diagnosis and etiopathology of the disease. Communicated by Ramaswamy H. Sarma 相似文献
992.
Al-Shammari Ahmed Majeed Jalill Raghad Dhyea Abdul Hussein Mohammed F. 《Molecular biology reports》2020,47(3):1691-1702
Molecular Biology Reports - Phytotherapy has been used to treat a different type of diseases including cancer for a long time, and it was a source for different active anti-tumor agents. Oncolytic... 相似文献
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994.
Neurochemical Research - Post-translational modification (PTMs) of proteins by ubiquitin and ubiquitin-like modifiers such as interferon-stimulated gene 15 (ISG15) and small ubiquitin-related... 相似文献
995.
S. Bushra M. Aslam M.A. Aziz M. Ahmed 《Archives Of Phytopathology And Plant Protection》2013,46(2):205-214
This study was carried out to see the impact of Angoumois grain moth (AGM) on different cultivars of barley so that we must grow resistant variety of barley or improve those which are susceptible to it. Eggs of Sitotroga cerealella (Oliv.) were collected and reared in incubators available in Stored Product Entomology Laboratory, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, under temperature 27 ± 2°C and 60 ± 2% relative humidity. For the experiment, five different cultivars of barley; Sanober-96, Jau-83, Soorab-96, ICBA and Sterling were selected for AGM feed. After an interval of 30, 60 and 90 days of infestation, percentage damage and weight loss in grains were determined. After carrying out laboratory and field germination tests, viability of different cultivars were checked. Damage was maximum in variety Soorab (99.38%), which becomes susceptible while it was minimum in Sanober-96 (90.62%), which becomes resistant. Weight loss was maximum in variety Soorab (49.71%), which becomes susceptible and was minimum in Sanober-96 (45.32%), which becomes resistant. Damage was positively correlated with weight loss and negatively correlated with seed germination. In germination tests, on filter paper, maximum germination was found in variety Sterling (3%) which becomes resistant and it was minimum in ICBA which becomes susceptible (0%). In sand germination test, maximum seeds germinated in variety Sanober-96 (2%), and minimum seeds germinated in ICBA (0%). By calculating the percentage of losses of different cultivars, it was found that none of cultivars proved itself completely resistant or susceptible. 相似文献
996.
Aman Shah Abdul Majid Amin Malik Shah Abdul Majid Zheng Qin Yin Dan Ji 《Neurochemical research》2013,38(7):1375-1393
Hydrogen sulphide (H2S) is one of three gaseous signaling molecules after nitric oxide and carbon monoxide. Various H2S donor compounds have been synthesized to study its physiological function. Among these compounds sodium hydrosulphide (NaHS), a donor of releasing H2S rapidly have shown to be protective in certain neuronal cell line but several in vivo studies have generated conflicting data. Furthermore several slow releasing H2S donors have been shown to have positive effects on cells in culture. The intracellular concentration of H2S and hence its rate of production may be a factor in keeping the balance between its neuroprotective and toxic effects. The present study was undertaken to deduce how a rapid releasing H2S donor (NaHS) as opposed to a slow releasing donor (ADTOH), affect oxidative stress related intracellular components and survival of RGC-5 cells. It was concluded that when RGC-5 cells are exposed to the toxic effects of glutamate in combination with buthionine sulfoxime (Glu/BSO), ADTOH was more efficacious in inhibiting apoptosis, scavenging reactive oxygen species (ROS), stimulation of glutathione (GSH) and gluthathione-S-transferase (GST). Western blot and qPCR analysis showed ADTOH increased the levels of Nrf2, HO-1, PKCα, p-Akt, Bcl-2 and XIAP but caused a decrease of Nfκβ and xCT greater than NaHS. This study is first to compare the efficacy of two H2S donor drugs as potential neuroprotectants and demonstrate that slow regulated release of H2S to cell culture can be more beneficial in inhibiting oxidative stress induced cell death. 相似文献
997.
Lindsey Walsh Abdul Gbaj Laura L. Etchells Kenneth T. Douglas Elena V. Bichenkova 《Journal of biomolecular structure & dynamics》2013,31(6):629-640
Abstract We report the first use of exciplex-based split-probes for detection of the wild type and *3 mutant alleles of human cytochrome P450 2C9. A tandem 8-mer split DNA oligonucleotide probe system was designed that allows detection of the complementary target DNA sequence. This exciplex-based fluorescence detector system operates by means of a contiguous hybridization of two oligonucleotide exciplex split-probes to a complementary target nucleic acid target. Each probe oligonucleotide is chemically modified at one of its termini by a potential exciplex-forming partner, each of which is fluorescently silent at the wavelength of detection. Under conditions that ensure correct three-dimensional assembly, the chemical moieties on suitable photoexcitation form an exciplex that fluoresces with a large Stokes shift (in this case 130 nm). Preliminary proof-of-concept studies used two 8-mer probe oligonucleotides, but in order to give better specificity for genomic applications, probe length was extended to give coverage of 24 bases. Eight pairs of tandem 12-mer oligonucleotide probes spanning the 2C9*3 region were designed and tested to find the best set of probes. Target sequences tested were in the form of (i) synthetic oligonucleotides, (ii) embedded in short PCR products (150 bp), or (iii) inserted into plasmid DNA (~ 3 Kbp). The exciplex system was able to differentiate wild type and human cytochrome P450 2C9 *3 SNP (1075 A→C) alleles, based on fluorescence emission spectra and DNA melting curves, indicating promise for future applications in genetic testing and molecular diagnostics. 相似文献
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999.