MyMedR

Displaying all 7 publications

Abstract:

Sort:

Agricultural drought risk assessment of Northern New South Wales, Australia using geospatial techniques

Hoque MA, Pradhan B, Ahmed N, Sohel MSI

Sci Total Environ, 2020 Nov 17.
PMID: 33248778 DOI: 10.1016/j.scitotenv.2020.143600

Droughts are recurring events in Australia and cause a severe effect on agricultural and water resources. However, the studies about agricultural drought risk mapping are very limited in Australia. Therefore, a comprehensive agricultural drought risk assessment approach that incorporates all the risk components with their influencing criteria is essential to generate detailed drought risk information for operational drought management. A comprehensive agricultural drought risk assessment approach was prepared in this work incorporating all components of risk (hazard, vulnerability, exposure, and mitigation capacity) with their relevant criteria using geospatial techniques. The prepared approach is then applied to identify the spatial pattern of agricultural drought risk for Northern New South Wales region of Australia. A total of 16 relevant criteria under each risk component were considered, and fuzzy logic aided geospatial techniques were used to prepare vulnerability, exposure, hazard, and mitigation capacity indices. These indices were then incorporated to quantify agricultural drought risk comprehensively in the study area. The outputs depicted that about 19.2% and 41.7% areas are under very-high and moderate to high risk to agricultural droughts, respectively. The efficiency of the results is successfully evaluated using a drought inventory map. The generated spatial drought risk information produced by this study can assist relevant authorities in formulating proactive agricultural drought mitigation strategies.
Design and synthesis of mono and bicyclic tetrapeptides thioester as potent inhibitor of histone deacetylases

Hoque MA, Islam MS, Islam MN, Kato T, Nishino N, Ito A, et al.

Amino Acids, 2014 Oct;46(10):2435-44.
PMID: 25048030 DOI: 10.1007/s00726-014-1800-5

Inhibitors of histone deacetylases (HDACs) are a promising class of anticancer agents that have an effect on gene regulation. The naturally occurring cyclic depsipeptide FK228 containing disulfide and Largazole possessing thioester functionalities act as pro-drugs and share the same HDAC inhibition mechanism in cell. Inspired from these facts, we have reported bicyclic tetrapeptide disulfide HDAC inhibitors resembling FK228 with potent activity and enhanced selectivity. In the present study, we report the design and synthesis of several mono and bicyclic tetrapeptide thioester HDAC inhibitors that share the inhibition mechanism similar to Largazole. Most of the compounds showed HDAC1 and HDAC4 inhibition and p21 promoting activity in nanomolar ranges. Among these the monocyclic peptides 1, 2 and bicyclic peptide, 4 are notable demanding more advanced research to be promising anticancer drug candidates.
Fulltext Aggregation behavior of cetyldimethylethylammonium bromide under the influence of bovine serum albumin in aqueous/electrolyte solutions at various temperatures and compositions: conductivity and molecular dynamics study

Ahmed MF, Molla MR, Saha M, Shahriar I, Rahman MS, Halim MA, et al.

RSC Adv, 2019 Feb 22;9(12):6556-6567.
PMID: 35518479 DOI: 10.1039/c9ra00070d

Herein, we have investigated the interaction of bovine serum albumin (BSA), the most abundant globular protein, with a conventional cationic surfactant, cetyldimethylethylammonium bromide (CDMEAB), through a conductivity technique in the absence/presence of electrolyte solutions at various temperatures (298.15-323.15 K). The interaction of the protein with drugs/surfactants and other additives plays a crucial role in the body. Hence, the main concern of the study is to extract the impact of BSA on surfactant molecules and vice versa. From the specific conductivity versus concentration of surfactant plots, three different noticeable critical micelle concentration (c*) values were obtained for pure CDMEAB and its mixture with protein/protein + salts. The presence of BSA and electrolytes altered the c* values of CDMEAB revealing interactions among the studied constituents where the salt solutions reduced the c* values and created a convenient environment for favorable micellization. The negative magnitudes achieved for standard free energy changes (ΔG 0 m) suggest spontaneity of micellization while the values of ΔH 0 m and ΔS 0 m signified the existence of some electrostatic and hydrophobic interactions. The values of molar heat capacity (ΔC 0 m) were positive as well as small which was an indication of less structural deformation. Molecular Dynamics (MD) simulation for all atoms revealed that the salt ions promoted non-covalent interaction between BSA and CDMEAB, and such interactions were not observed in the absence of the salt. Protein structure remained nearly same in spite of strong interaction with CDMEAB as evident from the overall RMSD (root-mean-square deviation) values of the alpha carbons and backbone of the protein and RMSF (root-mean-square fluctuation) values of the amino acid residues present in BSA. In this work thermodynamic parameters of transfer (such as ΔG 0 m.tr., ΔH 0 m.tr., and ΔC 0 p.m.tr.) were also evaluated and the results are discussed in detail. Besides, contributions of enthalpy and entropy to free energy changes were also analyzed.
Fulltext Antioxidative role of palm grass rhizome ameliorates anxiety and depression in experimental rodents and computer-aided model

Hoque MA, Ahmad S, Chakrabarty N, Khan MF, Hafez Kabir MS, Brishti A, et al.

Heliyon, 2021 Oct;7(10):e08199.
PMID: 34729435 DOI: 10.1016/j.heliyon.2021.e08199

Palm grass (Curculigo recurvata) is an ethnomedicinally important herb reported to have significant medicinal values. The present study aimed to evaluate the antidepressant and anxiolytic activities of a methanol extract of C. recurvata rhizome (Me-RCR) through different approaches. The antidepressant and anxiolytic properties of Me-RCR were assessed by using elevated plus maze (EPM), hole-board (HBT), tail suspension (TST), and forced swimming (FST) tests in Swiss Albino mice. The in-depth antioxidative potential of Me-RCR was also evaluated through DPPH radical scavenging activity, ferric-reducing power capacity, total phenolic, flavonoid, flavonol, and antioxidant content analysis. Computational investigations were performed using computer-aided methods for screening the anxiolytic, antidepressant, and antioxidative activities of the selected lead molecules. Treatment with Me-RCR (200 and 400 mg/kg, b.w.) notably increased the number of open arm entries and the time spent in the EPM test. In the HBT, Me-RCR exhibited significant anxiolytic activity at a dose of 200 mg/kg, whereas similar activity was observed at 400 mg/kg in the EPM test. Me-RCR significantly decreased the immobility time in a dose-dependent manner in both TST and FST. The IC50 for DPPH and reducing power capacity assay were found to be 18.56 and 193 μg/mL, respectively. Promising outcomes were noted for the determination of total phenolics, flavonoids, flavonols, and antioxidant capacity. In the case of computer-aided studies, nyasicoside showed promising binding energy for antidepressant and anxiolytic activities, whereas isocurculigine demonstrated promising effects as an antioxidant. Overall, these findings suggest that Me-RCR could be a favourable therapeutic candidate for the treatment of mental and psychiatric disorders, as well as a good source of antioxidants.
Physicochemical approaches reveal the impact of electrolytes and hydrotropic salt on micellization and phase separation behavior of polymer polyvinyl alcohol and surfactant mixture

Rather SU, Rahman MH, Bamufleh HS, Alhumade H, Taimoor AA, Saeed U, et al.

Int J Biol Macromol, 2023 Apr 30;235:123761.
PMID: 36812977 DOI: 10.1016/j.ijbiomac.2023.123761

The polymer-surfactant mixture has usages in numerous industries mainly in the production of daily used materials. Herein, the micellization and phase separation nature of the sodium dodecyl sulfate (SDS) and TX-100 along with a synthetic water-soluble polymer-polyvinyl alcohol (PVA) have been conducted using conductivity and cloud point (CP) measurement tools. In the case of micellization study of SDS + PVA mixture by conductivity method, the CMC values were obtained to be dependent on the categories and extent of additives as well as temperature variation. Both categories of studies were performed in aq. solutions of sodium chloride (NaCl), sodium acetate (NaOAc), and sodium benzoate (NaBenz) media. The CP values of TX 100 + PVA were decreased and enhanced in simple electrolytes and sodium benzoate media respectively. In all cases, the free energy changes of micellization (∆Gm0) and clouding (∆Gc0) were obtained as negative and positive respectively. The enthalpy (∆Hm0) and entropy (∆Sm0) changes for SDS + PVA system micellization was negative and positive respectively in aq. NaCl and NaBenz media, and in aq. NaOAc medium the ∆Hm0 values were found negative while ∆Sm0 were found negative except at the highest studied temperature (323.15 K). The enthalpy-entropy compensation of both processes was also assessed and described clearly.
Fulltext Curculigo recurvata W.T.Aiton exhibits anti-nociceptive and anti-diarrheal effects in Albino mice and an in silico model

Ahmad S, Nasrin MS, Reza ASMA, Chakrabarty N, Hoque MA, Islam S, et al.

Animal Model Exp Med, 2020 Jun;3(2):169-181.
PMID: 32613176 DOI: 10.1002/ame2.12119

BACKGROUND: Curculigo recurvata (C. recurvata) is an enthnomedicinally important herb reported to have significant medicinal values. The present study aimed to explore the in vivo and in silico anti-nociceptive and anti-diarrheal effects of a C. recurvate rhizome methanol extract (Me-RCR).
METHODS: The analgesic effects of Me-RCR were assessed using acetic acid-induced writhing and the formalin-induced flicking test. The drugs were administered intraperitoneally (IP) at doses of 200 and 400 mg/kg body weight (bw). Anti-diarrheal activity was evaluated by assessing intestinal motility, hypersecretion, and fecal score in mice at oral doses of 200 and 400 mg/kg·bw. Computer facilitated analyses for anti-nociceptive and anti-diarrheal activities of three isolated compounds from C. recurvata were undertaken to identify the best-fit phytoconstituents.
RESULTS: The Me-RCR showed significant (P
Fulltext Identifying hotspots for antibiotic resistance emergence and selection, and elucidating pathways to human exposure: Application of a systems-thinking approach to aquaculture systems

Brunton LA, Desbois AP, Garza M, Wieland B, Mohan CV, Häsler B, et al.

Sci Total Environ, 2019 Oct 15;687:1344-1356.
PMID: 31412468 DOI: 10.1016/j.scitotenv.2019.06.134

Aquaculture systems are highly complex, dynamic and interconnected systems influenced by environmental, biological, cultural, socio-economic and human behavioural factors. Intensification of aquaculture production is likely to drive indiscriminate use of antibiotics to treat or prevent disease and increase productivity, often to compensate for management and husbandry deficiencies. Surveillance or monitoring of antibiotic usage (ABU) and antibiotic resistance (ABR) is often lacking or absent. Consequently, there are knowledge gaps for the risk of ABR emergence and human exposure to ABR in these systems and the wider environment. The aim of this study was to use a systems-thinking approach to map two aquaculture systems in Vietnam - striped catfish and white-leg shrimp - to identify hotspots for emergence and selection of resistance, and human exposure to antibiotics and antibiotic-resistant bacteria. System mapping was conducted by stakeholders at an interdisciplinary workshop in Hanoi, Vietnam during January 2018, and the maps generated were refined until consensus. Thereafter, literature was reviewed to complement and cross-reference information and to validate the final maps. The maps and component interactions with the environment revealed the grow-out phase, where juveniles are cultured to harvest size, to be a key hotspot for emergence of ABR in both systems due to direct and indirect ABU, exposure to water contaminated with antibiotics and antibiotic-resistant bacteria, and duration of this stage. The pathways for human exposure to antibiotics and ABR were characterised as: occupational (on-farm and at different handling points along the value chain), through consumption (bacterial contamination and residues) and by environmental routes. By using systems thinking and mapping by stakeholders to identify hotspots we demonstrate the applicability of an integrated, interdisciplinary approach to characterising ABU in aquaculture. This work provides a foundation to quantify risks at different points, understand interactions between components, and identify stakeholders who can lead and implement change.