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1.
Acta Trop ; 258: 107356, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39128617

RESUMEN

Tropical and subtropical regions face millions of deaths from mosquito-borne illnesses yearly. Insecticides prevent transmission but pose health risks like dermatitis and allergies. The primary objective was to mitigate the recurring dependence on synthetic insecticides, thereby curbing the development of mosquito resistance. Leaves of Cymbopogon flexuosus (lemongrass) was collected from Mayurbhanj, India, processed, then extracted by steam distillation for essential oils & analyzed spectroscopically. Larvicidal assays were performed across varying concentrations, revealing the significant mortality induced by the Cymbopogon flexuosus extract against Anopheles stephensi larvae. 3D structure was modelled by using G protein-coupled receptors (GPCR) sequence and structural stability was also validated. After docking the binding free energy was determined from GPCR protein with ß-citral complex. Molecular dynamics (MD) study was conducted on the docked pose that displayed an optimal interactome profile. The larvicidal assay at the 12th and 24th hour revealed the highest LC50 (lethal concentration) of 23.493 ppm and 19.664 ppm . ß-Citral has a high binding affinity and an identifiable binding site, which suggests that it may play a larvicidal role in regulating the receptor's function by creating stable complexes with it. ß-Citral from lemongrass oils has potential larvicidal activity and effective against GPCR family 1 of mosquito and highly effective repellents against mosquito-borne diseases.


Asunto(s)
Anopheles , Cymbopogon , Insecticidas , Larva , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Animales , Larva/efectos de los fármacos , Insecticidas/farmacología , Insecticidas/química , Anopheles/efectos de los fármacos , Cymbopogon/química , India , Hojas de la Planta/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Monoterpenos Acíclicos/farmacología , Monoterpenos Acíclicos/química , Aceites Volátiles/farmacología , Aceites Volátiles/química , Receptores Acoplados a Proteínas G/metabolismo
2.
Mol Biotechnol ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619800

RESUMEN

Booster doses are crucial against severe COVID-19, as rapid virus mutations and variant emergence prolong the pandemic crisis. The virus's quick evolution, short generation-time, and adaptive changes impact virulence and evolvability, helping predictions about variant of concerns' (VOCs') landscapes. Here, in this study, we used a new computational algorithm, to predict the mutational pattern in SARS-CoV-2 ssRNA, proteomics, structural identification, mutation stability, and functional correlation, as well as immune escape mechanisms. Interestingly, the sequence diversity of SARS Coronavirus-2 has demonstrated a predominance of G- > A and C- > U substitutions. The best validation statistics are explored here in seven homologous models of the expected mutant SARS-CoV-2 spike ssRNA and employed for hACE2 and IgG interactions. The interactome profile of SARS-CoV-2 spike with hACE2 and IgG revealed a strong correlation between phylogeny and divergence time. The systematic adaptation of SARS-CoV-2 spike ssRNA influences infectivity and immune escape. Data suggest higher propensity of Adenine rich sequence promotes MHC system avoidance, preferred by A-rich codons. Phylogenetic data revealed the evolution of SARS-CoV-2 lineages' epidemiology. Our findings may unveil processes governing the genesis of immune-resistant variants, prompting a critical reassessment of the coronavirus mutation rate and exploration of hypotheses beyond mechanical aspects.

3.
Mol Biotechnol ; 66(1): 26-33, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36988875

RESUMEN

The occurrence of allergy, a type I hypersensitivity reaction, is rising exponentially all over the world. Sometimes, allergy proves to be fatal for atopic patients, due to the occurrence of anaphylaxis. This study is aimed to find an anti-allergic agent that can inhibit the binding of IgE to Human High Affinity IgE Receptor (FCεRI), thereby preventing the degranulation of mast cells. A considerable number of potential anti-allergic compounds were assessed for their inhibitory strength through ADMET studies. AUTODOCK was used for estimating the binding energy between anti-allergic compounds and FCεRI, along with the interacting amino acids. The docked pose showing favorable binding energy was subjected to molecular dynamics simulation study. Marrubiin, a diterpenoid lactone from Lamiaceae, and epicatechin-3-gallate appears to be effective in blocking the Human High Affinity IgE Receptor (FCεRI). This in-silico study proposes the use of marrubiin and epicatechin-3-gallate, in the downregulation of allergic responses. Due to the better inhibition constant, future direction of this study is to analyze the safety and efficacy of marrubiin in anti-allergic activities through in-vivo clinical human trials.


Asunto(s)
Anafilaxia , Antialérgicos , Diterpenos , Hipersensibilidad , Humanos , Antialérgicos/farmacología , Antialérgicos/uso terapéutico , Receptores de IgE/química , Receptores de IgE/metabolismo , Receptores de IgE/uso terapéutico , Inmunoglobulina E/química , Inmunoglobulina E/metabolismo , Inmunoglobulina E/uso terapéutico , Inmunoinformática , Estudios Prospectivos , Hipersensibilidad/tratamiento farmacológico , Hipersensibilidad/metabolismo , Anafilaxia/tratamiento farmacológico , Anafilaxia/prevención & control
4.
Int Immunopharmacol ; 123: 110636, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37499394

RESUMEN

BACKGROUND: Recently, in Nov 2021, in South Africa, the SARS CoV-2 variant Omicron was found to be highly infectious and transmissible but with the least fatality. It occupies the nasopharynx-oropharynx and easily spreads. The epidemiological data/reports suggest that several vaccines failed to neutralize Omicron. It has a large number of spike mutations and the RNA/protein vaccines were developed from its predecessors that may justify its escape in most neutralization reactions. Its lower immuno-suppression/cytokine-storming/inflammatory-response effects need exploration. OBJECTIVES: In the current study, we attempted to delineate the comparative interaction of different variants' spikes with multiple recognition sites on IgG and HLA-typing of MHC class and I and II. METHODS: All SARS-CoV-2 spike-proteins/human-IgG/MHC-I & II were obtained from the NCBI/ PDB/GISAID database. Initial 3D-structures of the unavailable proteins were constructed by Homology-Modeling (Swissmodel-Expasy) and optimized (PROCHECK). Molecular-docking of spike-IgG/spike- I & MHC-II was performed (HADDOCK2.4/HawkDock) with active-residue screening (CPORT). Antigenicity of epitopes was determined (Vaxigen v2.0-server) and the epitope-model prepared (PEP-FOLD3-server). The binding-affinity/biological-interfaces/visualize were performed (PRODIGY-PyMOL2). We also examined the genesis of feasible transition pathways of functional docked complexes (iMODs) of MHC with different epitopes and antibodies of IgG with different variants. Further, Molecular-Dynamic-Simulation was performed by GROMACS 2023.1 software package. The MD-simulation was run with 100 ns (300 k-heating/1-atm pressure). RESULTS: Surface-area with interactomes, H-bonding and polar/non-polar bonding were the highest in Omicron spike-IgG interaction. Unlike other variants, both the L and H chains of at least three different recognition sites of IgG interact with the N-terminal and C-terminal RBD of the S1-portion and partially bind to S2. In other cases, binding was observed in either NTD or CTD with a lesser number of bonding-interactomes, especially in Delta spike-Ab interaction. In the case of MHC class-I & II, the highest binding affinity/surface was noticed by Omicron and least by the Delta variant. The MD simulation data of lower RMSD values of the Delta and Omicron variants indicate improved structural stability and less departure from the initial conformation. Better binding to the IgG and MHC molecules explains Omicron's little ability in immune invasion.


Asunto(s)
COVID-19 , Humanos , Epítopos , SARS-CoV-2 , Simulación de Dinámica Molecular
5.
J Dent (Shiraz) ; 24(1): 71-75, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36864994

RESUMEN

Open reduction and internal fixation (ORIF) of mandibular condylar fracture with a three dimensional stabilization has been a controversial topic in oral and maxillofacial surgery. Miniplates and many 3D plates have been used till now for fixation of condylar fracture and delta plate is one of them. Present literature has less evidence about which one is superior over another. We have tried to evaluate the clinical performance of the delta miniplate in this study. A total of 10 patients presenting mandibular condylar fracture were treated by ORIF using delta miniplate. Dimensional details were measured of 10 dry human mandibles. At the end of 1-year follow-up period, all patients had satisfactory results, both clinically and radiologically. Delta plate showed better stability in the condylar region and less complication associated with plating system.

6.
Natl J Maxillofac Surg ; 14(3): 471-476, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38273923

RESUMEN

Purpose: Postoperative pulmonary complications (PPCs) are one of the most significant complications following head and neck cancer surgery (HNCS). Patients requiring tracheostomy, free tissue transfer reconstruction, and postoperative ventilation in an intensive care unit (ICU) may have a high incidence of PPCs. This study aimed to identify the most likely situations for developing PPCs in HNCS. Materials and Methods: A retrospective analysis of 40 patients who had undergone HNCS has been conducted. We individually traced each patient for 7 days postoperatively and collected data on various parameters. Result: The incidence of PPCs after HNCS is more with free flap reconstruction. Patient-related risk factors with PPCs were advanced age, smoking, body mass index (BMI) >25, and bilateral or unilateral neck dissection. Postoperative ICU stay was significantly related to an increased incidence of PPCs. In terms of specific surgical sites, both the maxilla and mandible also showed significant relationship with PPCs. Tracheostomy was also considered a related factor in developing PPCs. Conclusion: To reduce PPCs in HNCS, patients with one or more of these risk factors should be subjected to exaggerated postoperative pulmonary care.

7.
Mol Biol Res Commun ; 11(4): 155-166, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36777001

RESUMEN

Pandemic coronavirus causes respiratory, enteric and sometimes neurological diseases. Proteome data of individual coronavirus strains were already reported. Here we investigated of SARS-CoV-2 ssRNA and protein of spike, envelope and membrane to determine stress adaptation profile. Thermodynamic properties, Physicochemical behaviour and, amino acid composition along with their RMSD value was analysed. Thermodynamic index of SARS-CoV2 spike, envelope and membrane ssRNA is unstable in higher temperature. Presence of higher proportion of polar with positive and negative charged amino acid residues into spike (S), envelope (E) and membrane (M) protein indicate the lower stress adaptability pattern. Our study represented several unstable pockets into S, E and M proteins of SARS-CoV-2 against different abiotic stresses, specifically higher in spike protein. Contact with heat through solvent may denature the architectural network of SARS-CoV-2 spike, envelope and membrane ssRNA and structural protein. The stress instability index of SARS-CoV-2 and the interactome profile of its transmembrane proteins may help to reveal novel factors for inhibiting SARS-CoV-2 growth.

8.
J Antibiot (Tokyo) ; 72(5): 282-290, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30799437

RESUMEN

Mycobacterium tuberculosis (MTB) is commonly resistant to various drugs. Multidrug-resistant tuberculosis (MDR-MTB) is mostly caused by mutation in drug-binding proteins and protein folding. The aim of the study was to identify the pattern of mutations in embC, inhA and rpoB proteins and investigate its interactions with available drug such as rifampicin, ethambutol and isoniazid, using a computer docking method. The evolution of drugs resistant mechanisms of MTB was analyzed using an in silico approach. The model proteins were considered to be in a protein-protein interaction network among the twenty transmembrane proteins. The changes in structural conformation may describe the significance of the proton pumps system. The docking analysis revealed that unlike isoniazid, both rifampicin and ethambutol, bound to the same residues in mutant and wild forms. Moreover, multiple-sequence alignment (MSA) showed mutational hotspot regions where the substitution of amino acids in these three target proteins was position specific under stress. The molecular basis of drug resistance in M. tuberculosis can be represented by a protein network which is a well-regulated system for efflux pump activation by popularly used drugs. Ethambutol and rifampicin form stable complexes with EmbC and RpoB, respectively. Isoniazid shows no binding affinity to mutant InhA (2015). Analysis of the cellular network associated with drug regulatory proteins suggest that mmpl3, Rv1634 and Rv1258c play a major role by altering the protein pump to remove the active drug compounds from the bacterial cell.


Asunto(s)
Antituberculosos/metabolismo , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana Múltiple , Proteínas de Transporte de Membrana/metabolismo , Proteínas Mutantes/metabolismo , Mycobacterium tuberculosis/metabolismo , Proteínas Bacterianas/genética , Transporte Biológico Activo , Evolución Molecular , Proteínas de Transporte de Membrana/genética , Simulación del Acoplamiento Molecular , Proteínas Mutantes/genética , Mycobacterium tuberculosis/genética , Unión Proteica , Mapas de Interacción de Proteínas , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
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