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1.
Heliyon ; 10(9): e29566, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38707390

RESUMEN

The newly synthesized imidazole derivative namely, 4,5-bis[(E)-2-phenylethenyl]-1H,1'H-2,2'-biimidazole (KA1), was studied for its molecular geometry, docking studies, spectral analysis and density functional theory (DFT) studies. Experimental vibrational frequencies were compared with scaled ones. The reactivity sites were determined using average localized ionization analysis (ALIE), electron localized function (ELF), localized orbital locator (LOL), reduced density gradient (RDG), Fukui functions and frontier molecular orbital (FMO). Due to the solvent effect, a lower gas phase energy gap was observed. Through utilization of the noncovalent interaction (NCI) method, the hydrogen bond interaction, steric effect and Vander Walls interaction were investigated. Molecular docking simulations were employed to determine the specific atom inside the molecules that exhibits a preference for binding with protein. The parameters for the molecular electrostatic potential (MESP) and global reactivity descriptors were also determined. The thermodynamic characteristics were determined through calculations employing the B3LYP/cc-pVDZ basis set. Antimicrobial activity was carried out using the five different microorganisms like Escherichia coli, Streptococcus pneumoniae, Staphylococcus aureus, Klebsiella pneumoniae and Candida albicans.

2.
J Biomol Struct Dyn ; : 1-16, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656235

RESUMEN

The novel Schiff's base (CS6) was synthesized and confirmed by various studies. The B3LYP/cc-pVDZ basis set was used for theoretical study and the results indicated that both the theoretical and experimental studies correlated well. The interaction energy of CS6-water complex calculated by using the local energy decomposition analysis was found to be -7.28 kcal/mol. The TD-TFT method was used for the calculation of electronic absorption spectrum. This study confirmed that the observed wavelength and the simulated wavelength in the electronic spectra were almost similar. The electrophilic and nucleophilic attacking sites of the titled compound were identified by using FMO and MEP studies. The highest stabilization energy (30.19 kcal/mol) formed by LP (2) O24 to anti-bonding σ*(C18-C19) was confirmed by the NBO study. The localized and delocalized electrons were confirmed by ELF and LOL studies. The hydrogen bond interaction as well as the physical and chemical properties of CS6 indicated that it showed a moderate similarity to the drugs. The docking study confirmed that the dehydro-L-gulonate decarboxylase inhibitor (1Q6O) could interact with CS6 compound with the binding energy of -5.26 kcal/mol.Communicated by Ramaswamy H. Sarma.

3.
Heliyon ; 10(7): e28623, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38590870

RESUMEN

The (E)-4-((4-hydroxy-3-methoxy-5-nitrobenzylidene) amino) pyrimidin-2(1H)-one (C5NV) was synthesized from cytosine and 5-nitrovanilline by simple straightforward condensation reaction. The structural characteristics of the compound was determined and optimized by WB97XD/cc-pVDZ basis set. The vibrational frequencies were computed and subsequently compared to the experimental frequencies. We investiated the electronic properties of the synthesized compound in gas and solvent phases using the time-dependent density functional theory (TD-DFT) approach, and compared them to experimental values. The fluorescence study showed three different wavelengths indicating the nature of the optical material properties. Frontier molecular orbital (FMO) and molecular electrostatic potential (MEP) analyses were conducted for the title compound, and electron localized functions (ELF) and localized orbital locators (LOL) were used to identify the orbital positions of localized and delocalized atoms. Non-covalent interactions (H-bond interactions) were investigated using reduced density gradients (RDGs). The objective of the study was to determine the physical, chemical, and biological properties of the C5NV. The molecular docking study was conducted between C5NV and 2XNF protein, its lowest binding energy score is -7.92 kcal/mol.

4.
J Biomol Struct Dyn ; : 1-20, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38577881

RESUMEN

The N, N'-(1,2-phenylene) bis (1- (4- chlorophenyl) methanimine) (CS4) was synthesized and characterized by infrared (IR), absorption (UV-vis) and NMR (1H and 13C) spectral analyses. The structural parameters, vibrational frequencies, potential energy and the distribution analysis (PED) were calculated by using DFT with the basis set of B3LYP/cc-pVDZ and these spectral values were compared to the experimental values. HOMO and LUMO studied were performed in order to understand the stability and biological activity of the compound. The most reactive sites on the compound were investigated by utilizing MEP energy surface and Fukui function descriptor with the natural population analysis (NPA) of the charges. The study of the natural bond orbitals (NBO) reveals the delocalization of the intramolecular interaction of the charges in the compound. Additionally, topological investigations (ELF, LOL), determination of thermodynamic parameters and noncovalent interaction (NCI) study by using topology (RDG) analysis were also carried out. Finally, the molecular docking and molecular dynamics simulations was carried out by examining against glycosylphosphatidylinositol phospholipase D inhibitor receptor for distinct protein targets (3MZG).Communicated by Ramaswamy H. Sarma.

5.
J Biomol Struct Dyn ; : 1-14, 2023 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-37978905

RESUMEN

The utilization of the density functional theory (DFT) methodology has developed as a highly efficient method for investigating molecular structure and vibrational spectra, and it is increasingly being employed in various applications relating to biological systems. This study focuses on conducting investigations, both experimental and computed, to analyze the molecular structure, electronic properties and features of (E)-4-(((9H-purin-6-yl)imino)methyl)-2-methoxyphenol (ANVA). The expression ANVA should be rewritten as follows: the compound is a derivative of adenine (primary amine), specifically a vanillin (aldehyde). The present study reports the synthesis, characterization, DFT, docking and antimicrobial activity of ANVA. The optimization of the molecular structure was conducted, and the determination of its structural features was performed using DFT with the B3LYP/cc-pVDZ method. The vibrational assignments were determined in detail by analyzing the potential energy distribution. A strong correlation was observed between the spectra that were observed and the spectra that were calculated. The calculation of intramolecular charge transfer was performed using natural bond orbital analysis. In addition, several computational methods were employed, including highest occupied molecular orbital-least unoccupied molecular orbital analysis, molecular electrostatic potential calculations, non-linear optical, reduced density gradient, localization orbital locator and electron localization function analysis. This paper examines the present use of adenine derivatives in combatting bacterial and fungal infections, as well as the inclusion of spectral and quantum chemical calculations in the discussion.Communicated by Ramaswamy H. Sarma.

6.
Heliyon ; 7(8): e07724, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34458601

RESUMEN

The Schiff base (E)-4-((2-hydroxy-3,5-diiodobenzylidene)amino)-N-(pyrimidine)-2-yl) benzene sulfonamide (DIDA) compound was synthesis with condensation of 3,5-diiodosalicylaldehyde and sulfadiazine. The compound characterized with FTIR, X-ray crystallography and electronic spectra. The titled compound associated with experimental and theoretical method, DFT used for the theoretical method. The IR was calculated from DFT mode with B3LYP/GENSEP basic set. The electronic spectra computed from TD-DFT method with CAM-B3LYP functional, with IEFPCM solvation model and DMSO used as the solvent. Wave function based properties like localized orbital locator, electron localization function and non-covalent interactions have been studied extensively. The ADMET properties of the compound DIDA indicated that the compound has excellent drug likeness properties and PASS studies showed that it has anti-infective properties, which is confirmed by a docking score of -7.4 kcal/mol.

7.
MethodsX ; 8: 101326, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34434840

RESUMEN

Validation of a survey instrument is an important activity in the research process. Face validity and content validity, though being qualitative methods, are essential steps in validating how far the survey instrument can measure what it is intended for. These techniques are used in both scale development processes and a questionnaire that may contain multiple scales. In the face and content validation, a survey instrument is usually validated by experts from academics and practitioners from field or industry. Researchers face challenges in conducting a proper validation because of the lack of an appropriate method for communicating the requirement and receiving the feedback. In this Paper, the authors develop a template that could be used for the validation of survey instrument. In instrument development process, after the item pool is generated, the template is completed and sent to the reviewer. The reviewer will be able to give the necessary feedback through the template that will be helpful to the researcher in improving the instrument.

8.
Equine Vet J ; 50(5): 636-643, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29356055

RESUMEN

BACKGROUND: Cerebellar Purkinje cell axonal degeneration has been identified in horses with shivering but its relationship with abnormal hindlimb movement has not been elucidated. OBJECTIVES: To characterise surface electromyographic (sEMG) hindlimb muscle activity in horses with shivering, correlate with clinical scores and examine horses for Purkinje axonal degeneration. STUDY DESIGN: Descriptive controlled clinical study. METHODS: The hindlimb of seven shivering and six control draught horses were clinically scored. Biceps femoris (BF), vastus lateralis (VL), tensor fasciae latae and extensor digitorum longus were recorded via sEMG during forward/backward walking and trotting. Integrated (iEMG) and peak EMG activity were compared between groups and correlated with clinical locomotor exam scores. Sections of the deep cerebellar nuclei (DCN) of six of the seven shivering horses were examined with calbindin immunohistochemistry. RESULTS: In control horses, backward walking resembled forward walking (right hindlimb peak EMG: backward: 47.5 ± 21.9%, forward: 36.9 ± 15.7%) but displayed significantly higher amplitudes during trotting (76.1 ± 3.4%). However, in shivering horses, backward walking was significantly different from forward (backward: 88.5 ± 21.5%, forward: 49.2 ± 8.9%), and resembled activity during trotting (81.4 ± 4.8%). Specific to backward walking, mean sEMG amplitude fell outside two standard deviations of mean control sEMG for ≥25% of the stride in the BF for all seven and the VL for six of the seven shivering horses. Locomotor exam scores were correlated with peak EMG (r = 0.87) and iEMG (r = 0.87). Calbindin-positive spheroids were present in Purkinje axons in DCN of all shivering horses examined. MAIN LIMITATIONS: The neuropathological examination focused specifically on the DCN and, therefore, we cannot fully exclude additional lesions that may have influenced abnormal sEMG findings in shivering horses. CONCLUSION: Shivering is characterised by abnormally elevated muscle recruitment particularly in BF and VL muscles during backward walking and associated with selective Purkinje cell distal axonal degeneration.


Asunto(s)
Axones/patología , Enfermedades Cerebelosas/veterinaria , Enfermedades de los Caballos/patología , Enfermedades Musculares/veterinaria , Degeneración Nerviosa/veterinaria , Enfermedades del Sistema Nervioso Periférico/veterinaria , Animales , Enfermedades Cerebelosas/patología , Caballos , Trastornos del Movimiento/patología , Trastornos del Movimiento/veterinaria , Enfermedades Musculares/patología , Mioclonía/patología , Mioclonía/veterinaria , Degeneración Nerviosa/patología , Enfermedades del Sistema Nervioso Periférico/patología , Células de Purkinje/patología
10.
Psychiatry Res ; 65(2): 65-71, 1996 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-9122287

RESUMEN

We investigated prolactin (PRL) and growth hormone (GH) secretion during acute and late abstinence following methylphenidate (MP) administration. Ten male patients who were undergoing acute cocaine abstinence and nine control subjects were randomly assigned into one of two possible sequences of MP and placebo, with each experimental condition occurring on two successive days. This procedure was repeated after 7 days for the patients. Baseline measures were analyzed by analysis of variance (ANOVA) with post hoc tests. Measures of MP challenge were analyzed by analysis of covariance (ANCOVA) with baseline as the covariate. Acute abstinence was compared with control values and then to late abstinence. Plasma levels of PRL, GH, and MP were measured along with a measure of clinical symptoms. Patients had higher basal PRL concentrations during acute abstinence compared with controls, and patients showed no difference when compared to themselves after 7 days (late abstinence). Provocation with MP yielded exaggerated PRL and GH responses in patients during acute abstinence compared with control values, and ANCOVA also revealed a significant increase in PRL response during late abstinence compared with acute abstinence. GH was a less sensitive indicator than PRL. Craving was exacerbated by MP during both acute and late abstinence and was possibly increased at late abstinence. This indicates that the perturbation in dopamine regulation persists and may be increased as clinical recovery occurs for most subjective symptoms. Blood pressure changes were variable and interpretation was uncertain.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Cocaína , Hormona de Crecimiento Humana/sangre , Metilfenidato , Trastornos Relacionados con Opioides/rehabilitación , Prolactina/sangre , Síndrome de Abstinencia a Sustancias/fisiopatología , Adulto , Nivel de Alerta/efectos de los fármacos , Nivel de Alerta/fisiología , Estimulantes del Sistema Nervioso Central/farmacocinética , Dopamina/fisiología , Esquema de Medicación , Humanos , Masculino , Metilfenidato/farmacocinética , Examen Neurológico/efectos de los fármacos , Trastornos Relacionados con Opioides/fisiopatología , Síndrome de Abstinencia a Sustancias/diagnóstico
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