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Biology subjects

Hoque Apu, E.

Publications and source records attributed to Hoque Apu, E..

3 recordsLinked to original sources

Regulating the proinflammatory response to implanted composite biomaterials comprising polylactide and hydroxyapatite by targeting immunometabolism

Composite biomaterials comprising polylactide (PLA) and hydroxyapatite (HA) are applied in bone, cartilage and dental regenerative medicine, where HA confers osteoconductive properties. However, after surgical implantation, adverse immune responses to these composites can occur, which have been attributed to size and morphology of HA particles. Approaches to effectively modulate these adverse immune responses have not been described. PLA degradation products have been shown to alter immune cell metabolism, which drives the inflammatory response. Therefore, we aimed to modulate the inflammatory response to composite biomaterials by regulating glycolytic flux with small molecule inhibitors incorporated into composites comprised of amorphous PLA (aPLA) and HA (aPLA+HA). Inhibition at specific steps in glycolysis reduced proinflammatory (CD86+CD206-) and increased pro-regenerative (CD206+) immune cell populations around implanted aPLA+HA resulting in a pro-regenerative microenvironment. Notably, neutrophil and dendritic cell (DC) numbers along with proinflammatory monocyte and macrophage populations were decreased, and Arginase 1 expression among DCs was increased. Targeting immunometabolism to control the inflammatory response to biomaterial composites, and creating a pro-regenerative microenvironment, is a significant advance in tissue engineering where immunomodulation enhances osseointegration, and angiogenesis, which will lead to improved bone regeneration.

bioengineering↗

Partial characterization and the evaluation of antimicrobial activities of silver nanoparticles biosynthesized from Cymbopogon citratus leaf extract

BackgroundSilver nanoparticles (AgNPs) are toxic to microorganisms and can potentially kill multidrug-resistant bacteria. Nanoparticles can be synthesized in many different ways, such as physical or chemical methods. Recently, it has been found that plant molecules can perform the same reduction reactions necessary for the production of nanoparticles but in a much more efficient way. ResultsHere, green chemistry was employed to synthesize silver nanoparticles using leaf extracts of Cymbopogon citratus. Effects of different parameters such as temperature, pH and volume of plant extract were also tested using their absorbance pattern at different wavelengths. The Surface Plasmon Resonance (SPR) changed with the changes in parameters. Changes in temperature from 20{degrees}C to 60{degrees}C have changed the highest absorbance from 0.972 to 3.893 with an SPR of 470 nm. At higher pH (11.1), the particles become highly unstable and have irregular shapes and sizes. At lower pH (3.97), the peak shifts to the right, indicating a smaller but unstable compound. We have also investigated the effect of the volume of plant extracts on the reaction time. The sample with the highest amount of plant extract showed the most absorbance with a value of 0.963 at {lambda}max, which was calculated to be 470 nm. The total formation of the AgNPs was observed visually with a color change from yellow to brownish-black. UV-visible spectroscopy was used to monitor the quantitative formation of silver nanoparticles, showing a signature peak in absorbance between 400 and 500 nm. We have estimated the size of the nanoparticles as 47nm by comparing the experimental data with the theoretical value using Mieplot. The biosynthesized silver nanoparticles showed enhanced antibacterial activity against several multidrug-resistant bacteria, determined based on the minimal inhibitory concentration and zone of inhibition. ConclusionThe findings of this study indicate that an aqueous extract of C. citratus can synthesize silver nanoparticles when silver nitrate is used as a precursor and silver nanoparticles act as antimicrobial properties enhancers. These findings can influence further studies in this field to better understand the properties and applications of nanoparticles.

molecular biology↗

CDK4 as a phytochemical based anticancer drug target

Success story of plant-based medicine had been overlooked during the advent of modern pharmaceutical industry. Despite the negligence of the multimillion-dollar drug industry, people entirely rely on medicinal plants in some part of the world. In this study, we have emphasized on going back to those traditional medicinal practices to figure out their underlying mechanism to move forward on phytochemical based drug development. We screened Medicinal Plant Database Bangladesh 1.0 (MPDB1.0) and on-going extension, MPDB2.0, of that database to find traditionally used medicinal plants and their active compounds. Here, Mangiferin, extracted from Mangifera indica, have been demonstrated to interact with cell cycle regulator Cyclin-dependent Kinase 4 (CDK4). CDK4 is differentially expressed during Glioblastoma multiforme (GBM), Brain Lower Grade Glioma (LGG), and Sarcoma (SARC). Expression of CDK4 is interlinked to the patients survival rate and its consistent expression throughout different stages have provided the advantage to use it as diagnostic tool and drug target. Altogether, this study demonstrated that simple mango tree extracted active compounds, mangiferin, can work as potential anticancer drug and leveraging the recent advancement of sequencing and gene expression data can accelerate the phytochemical based drug discovery process.

cancer biology↗