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101.
102.
Bilal Ahmad Maria Batool Moon-Suk Kim Sangdun Choi 《International journal of molecular sciences》2021,22(11)
Toll-like receptor (TLR) signaling plays a critical role in the induction and progression of autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematous, experimental autoimmune encephalitis, type 1 diabetes mellitus and neurodegenerative diseases. Deciphering antigen recognition by antibodies provides insights and defines the mechanism of action into the progression of immune responses. Multiple strategies, including phage display and hybridoma technologies, have been used to enhance the affinity of antibodies for their respective epitopes. Here, we investigate the TLR4 antibody-binding epitope by computational-driven approach. We demonstrate that three important residues, i.e., Y328, N329, and K349 of TLR4 antibody binding epitope identified upon in silico mutagenesis, affect not only the interaction and binding affinity of antibody but also influence the structural integrity of TLR4. Furthermore, we predict a novel epitope at the TLR4-MD2 interface which can be targeted and explored for therapeutic antibodies and small molecules. This technique provides an in-depth insight into antibody–antigen interactions at the resolution and will be beneficial for the development of new monoclonal antibodies. Computational techniques, if coupled with experimental methods, will shorten the duration of rational design and development of antibody therapeutics. 相似文献
103.
Farrukh Aqil Jeyaprakash Jeyabalan Radha Munagala Iqbal Ahmad David J. Schultz Ramesh C. Gupta 《International journal of molecular sciences》2021,22(12)
Breast cancer (BC) is a leading cause of cancer deaths in women in less developed countries and the second leading cause of cancer death in women in the U.S. In this study, we report the inhibition of E2-mediated mammary tumorigenesis by Cuminum cyminum (cumin) administered via the diet as cumin powder, as well as dried ethanolic extract. Groups of female ACI rats were given either an AIN-93M diet or a diet supplemented with cumin powder (5% and 7.5%, w/w) or dried ethanolic cumin extract (1%, w/w), and then challenged with subcutaneous E2 silastic implants (1.2 cm; 9 mg). The first appearance of a palpable mammary tumor was significantly delayed by both the cumin powder and extract. At the end of the study, the tumor incidence was 96% in the control group, whereas only 55% and 45% animals had palpable tumors in the cumin powder and extract groups, respectively. Significant reductions in tumor volume (660 ± 122 vs. 138 ± 49 and 75 ± 46 mm3) and tumor multiplicity (4.21 ± 0.43 vs. 1.16 ± 0.26 and 0.9 ± 0.29 tumors/animal) were also observed by the cumin powder and cumin extract groups, respectively. The cumin powder diet intervention dose- and time-dependently offset E2-related pituitary growth, and reduced the levels of circulating prolactin and the levels of PCNA in the mammary tissues. Mechanistically, the cumin powder diet resulted in a significant reversal of E2-associated modulation in ERα, CYP1A1 and CYP1B1. Further, the cumin powder diet reversed the expression levels of miRNAs (miR-182, miR-375, miR-127 and miR-206) that were highly modulated by E2 treatment. We analyzed the composition of the extract by GC/MS and established cymene and cuminaldehyde as major components, and further detected no signs of gross or systemic toxicity. Thus, cumin bioactives can significantly delay and prevent E2-mediated mammary tumorigenesis in a safe and effective manner, and warrant continued efforts to develop these clinically translatable spice bioactives as chemopreventives and therapeutics against BC. 相似文献
104.
Ahmad Jalloh Antwoine Flowers Charles Hudson Dale Chaput Jennifer Guergues Stanley M. Stevens Jr. Paula C. Bickford 《International journal of molecular sciences》2021,22(12)
Microglial activity in the aging neuroimmune system is a central player in aging-related dysfunction. Aging alters microglial function via shifts in protein signaling cascades. These shifts can propagate neurodegenerative pathology. Therapeutics require a multifaceted approach to understand and address the stochastic nature of this process. Polyphenols offer one such means of rectifying age-related decline. Our group used mass spectrometry (MS) analysis to explicate the complex nature of these aging microglial pathways. In our first experiment, we compared primary microglia isolated from young and aged rats and identified 197 significantly differentially expressed proteins between these groups. Then, we performed bioinformatic analysis to explore differences in canonical signaling cascades related to microglial homeostasis and function with age. In a second experiment, we investigated changes to these pathways in aged animals after 30-day dietary supplementation with NT-020, which is a blend of polyphenols. We identified 144 differentially expressed proteins between the NT-020 group and the control diet group via MS analysis. Bioinformatic analysis predicted an NT-020 driven reversal in the upregulation of age-related canonical pathways that control inflammation, cellular metabolism, and proteostasis. Our results highlight salient aspects of microglial aging at the level of protein interactions and demonstrate a potential role of polyphenols as therapeutics for age-associated dysfunction. 相似文献
105.
Zahid Hanif Zeeshan Ahmad Khan Dongho Shin Dongwhi Choi Sung Jea Park 《大分子材料与工程》2021,306(10):2100289
Cellulose nanocrystals (CNCs) incorporated with silver nanoparticles (AgNPs) photonic films have drawn considerable attention due to their plasmonic chiroptical activity. However, the exploitation of some fundamental properties for practical use such as the affinity analysis of metal nanoparticles attached to the surface of photonic films according to the solvent compatibility and antibacterial activity under physical conditions has yet not been studied. Hence, a facile process of in situ deposition of AgNPs into the chiral structure of CNC films is proposed. CNC photonic films, cross-linked by glutaraldehyde are prepared. This interaction generated the solvents-stable photonic film with a considerable amount of unreacted aldehyde functional groups that facilitates the reduction of Ag salt to AgNPs. The formed AgNPs in the photonic films show excellent stability over immersion in various polar and non-polar solvents. The post-solvent treated photonic films display excellent contact-based antibacterial behavior against gram-negative Escherichia coli. 相似文献
106.
Hydrotreatment of spent oil distillate was carried out on a commercial Ni-Mo-alumina catalyst in the temperature range 260–340 °C, with a liquid hourly space velocity (LHSV) of 0.7–2.0 h?1, pressure of 4.5 MPa and ratio of 300 NL L?1 (normal litre of H2 per litre of feedstock). U.v. spectra of hydrogenated and original spent oil distillates (measured in normal hexane) gave a band with a maximum at 230 nm. The change in absorbance at three selected wavelengths for original oil distillate and hydrotreated oil at different operating conditions was taken as a guide for the determination of hydrogenation reaction rates (including partial saturation of aromatics and sulphur compound hydrogenolysis). The rate constants of hydrogenation reactions (k) using a second-order equation and a model of two parallel first-order reactions (k1 and k2) were calculated. Finally, the apparent activation energy (Ea), enthalpy of activation () and entropy () were calculated based on the values of k, k1, and k2. The calculated values of Ea based on k, k1 and k2 were 81.479, 71.188 and 62.882 kJ mol?1, respectively. The values of based on the same rate constants were 76.670, 66.564 and 58.433 kJ mol?1, while the values of were ?117.150, ?133.779 and ?150.823 J mol?1 K?1, respectively. 相似文献
107.
M. S. Ahmad M. U. Ahmad A. A. Ansari S. M. Osman 《European Journal of Lipid Science and Technology》1978,80(9):353-354
Seeds from seven species of plants belonging to less familiar botanical families were analysed for oil and protein, and the fatty acid composition of the oils was determined by gas liquid chromatography. Oils from five species are interesting in containing high percentage (71.9–83.7%) of C18 unsaturated acids. Seeds from Tropaeolum majus contain oil which, on the basis of chromatographic analysis, appears to be a suitable industrial source of cis-11-eicosenoic and cis-13-docosenoic (erucic) acids. 相似文献
108.
Radiation-induced wood plastic composites (WPC) were prepared from five varieties of Bangladeshi timbers, using seven different types of monomers. The mixtures of double and triple monomers were investigated along with the single-monomer system for the preparation of composites. Among the three systems, single-monomer process showed the highest polymer loading with butylmethacrylate (BMA). Tensile strength (TS) property, represented as Tf = TSwpc/TSwood was determined. Highest Tf values were achieved with the soft wood. The effects of dose and dose rate, monomer concentration, and swelling agent were also studied. Suitable total dose was found to be 3 Mrad at 0.8 Mrad/h, and methanol exhibited the best swelling ability for the woods at a ratio of 1 : 9 v/v in all the monomer investigated. 相似文献
109.
M. U. Ahmad S. K. Husain S. M. Osman 《Journal of the American Oil Chemists' Society》1981,58(6):673-674
Seed oil ofPhyllanthus niruri (Euphorbiaceae) contains 1.2% ricinoleic (12-hydroxy-cis-9-octadecenoic) acid, previously unknown in the genusPhyllanthus. Identification is based on thin layer and gas liquid chromatography, infrared, nuclear magnetic resonance, and mass spectrometry
analysis as well as chemical methods. Other major components of the oil are linoleic acid (21%) and linolenic acid (51.4%).
Presented at the ISF/AOCS World Congress, April 1980, New York City. 相似文献
110.
M. U. Ahmad A. A. Ansari S. M. Osman 《European Journal of Lipid Science and Technology》1980,82(3):106-109
The reactions of 1,2-hexadecanediol and 1,2-octadecanediol with hydrogen bromide in the presence of acetic anhydride have been investigated. The treatment of hydrogen bromide (48%) in acetic anhydride with 1,2-hexadecanediol gives mainly 1-bromo-2-acetoxy hexadecane (66%), 2-acetoxy hexadecanol (26%), and 1,3-hexadecanediol (8%). Similar products result from 1,2-octadecanediol. The structures of the products are based on combustion data, spectroscopic, and chemical evidences. The mechanism of the reaction has been discussed. 相似文献