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1.
Stat Med ; 43(5): 983-1002, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38146838

RESUMEN

With the growing commonality of multi-omics datasets, there is now increasing evidence that integrated omics profiles lead to more efficient discovery of clinically actionable biomarkers that enable better disease outcome prediction and patient stratification. Several methods exist to perform host phenotype prediction from cross-sectional, single-omics data modalities but decentralized frameworks that jointly analyze multiple time-dependent omics data to highlight the integrative and dynamic impact of repeatedly measured biomarkers are currently limited. In this article, we propose a novel Bayesian ensemble method to consolidate prediction by combining information across several longitudinal and cross-sectional omics data layers. Unlike existing frequentist paradigms, our approach enables uncertainty quantification in prediction as well as interval estimation for a variety of quantities of interest based on posterior summaries. We apply our method to four published multi-omics datasets and demonstrate that it recapitulates known biology in addition to providing novel insights while also outperforming existing methods in estimation, prediction, and uncertainty quantification. Our open-source software is publicly available at https://github.com/himelmallick/IntegratedLearner.


Asunto(s)
Multiómica , Programas Informáticos , Humanos , Teorema de Bayes , Estudios Transversales , Biomarcadores
2.
Biometrics ; 78(3): 880-893, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-33864633

RESUMEN

Popular parametric and semiparametric hazards regression models for clustered survival data are inappropriate and inadequate when the unknown effects of different covariates and clustering are complex. This calls for a flexible modeling framework to yield efficient survival prediction. Moreover, for some survival studies involving time to occurrence of some asymptomatic events, survival times are typically interval censored between consecutive clinical inspections. In this article, we propose a robust semiparametric model for clustered interval-censored survival data under a paradigm of Bayesian ensemble learning, called soft Bayesian additive regression trees or SBART (Linero and Yang, 2018), which combines multiple sparse (soft) decision trees to attain excellent predictive accuracy. We develop a novel semiparametric hazards regression model by modeling the hazard function as a product of a parametric baseline hazard function and a nonparametric component that uses SBART to incorporate clustering, unknown functional forms of the main effects, and interaction effects of various covariates. In addition to being applicable for left-censored, right-censored, and interval-censored survival data, our methodology is implemented using a data augmentation scheme which allows for existing Bayesian backfitting algorithms to be used. We illustrate the practical implementation and advantages of our method via simulation studies and an analysis of a prostate cancer surgery study where dependence on the experience and skill level of the physicians leads to clustering of survival times. We conclude by discussing our method's applicability in studies involving high-dimensional data with complex underlying associations.


Asunto(s)
Algoritmos , Modelos Estadísticos , Teorema de Bayes , Análisis por Conglomerados , Simulación por Computador , Humanos , Masculino , Modelos de Riesgos Proporcionales , Análisis de Supervivencia
3.
Environ Res ; 204(Pt A): 111962, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34450158

RESUMEN

Since the last few decades, the green synthesis of metal nanoparticles was one of the most thrust areas due to its widespread application. The study proposed using wasted and unusable Humulus lupulus (Hops) extract to synthesize silver nanoparticles for biomedical application. The environment around us gives us many scopes to use the waste from environmental sources and turn it into something valuable. The spent Hops extract was used to synthesize silver nanoparticles (AgNP@HOPs), and the synthesized product exhibited an excellent therapeutic effect in terms of anti-bacterial and anti-cancer agents. The synthesis was optimized considering different factors like time and the concentration of AgNO3. The silver nanoparticles were characterized in detail using different characterization techniques XRD, DLS, TEM, BET, XPS, Raman Spectroscopy, SEM, EDAX, AFM, which revealed the uniqueness of the silver nanoparticles. The average hydrodynamic size was found to be 92.42 ± 2.41 with a low polydispersity index. The presence of Ag-C and Ag-O bonds in the AgNP@HOPs indicated that it is composed of organo-silver and silver oxides. The nanoparticles were found to be spherical with an average size of 17.40 nm. The AgNPs were lethal to both E. coli and S. aureus with a MIC-50 of 201.881 µg/mL and 213.189 µg/mL, respectively. The AgNP@HOPs also exhibited an anti-cancer effect with an IC-50 of 147.175. The AgNP@HOPs exhibited less cytotoxicity and genotoxicity against normal cells and exhibited superior haemocompatibility (major criteria for drug selection). There are indeed various reports on the synthesis of silver nanoparticles, but this study proposes a green method for producing non-genotoxic, non-hemolytic organometallic silver nanoparticles using waste material with considerable therapeutic index from the environmental source with potential application in the medical industry. This work could be taken forward for in-vivo studies and for pre clinical studies.


Asunto(s)
Humulus , Nanopartículas del Metal , Antibacterianos , Escherichia coli , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Plata , Staphylococcus aureus
4.
Environ Res ; 212(Pt E): 113534, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35654154

RESUMEN

Clays and its composites have received considerable attention recently due to their low cost, wide availability and low environmental impact. The development of various preparation processes and applications of innovative polymer-nanoclay composites has been aided by recent breakthroughs in material technologies. Novel polymer-nanoclay composites with better qualities have been effectively adopted in a variety of fields, including aerospace, car, construction, petroleum, biomedical, and wastewater treatment, owing to innovative production processes. Due to their superior qualities, such as increased density, strength, relatively large surface areas, high elastic modulus, flame retardancy, and thermomechanical/optoelectronic/magnetic capabilities, these composites are acknowledged as potential advanced materials. Hence the present paper reviews the advances in synthesis and preparation of clay-polymer nanocomposites. In addition, this study also focuses on the various techniques used for clay-polymer nanocomposites characterization e.g. scanning electron microscope (SEM), transmission electron microscope (TEM), thermo-gravimetric analysis (TGA) and differential colorimetric analysis (DSC), x-ray diffraction (XRD) analysis, Nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopic (FTIR) characterization. These advanced physico-mechanical and chemical characterization techniques would be effective in understanding the most appropriate application of clay polymer nanocomposites. In addition, the application of clay polymer nanocomposites in biomedical sector is also discussed in brief.


Asunto(s)
Nanocompuestos , Polímeros , Arcilla , Nanocompuestos/química , Polímeros/química , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
5.
Lifetime Data Anal ; 28(4): 723-743, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35933463

RESUMEN

Genitourinary surgeons and oncologists are particularly interested in whether a robotic surgery improves times to Prostate Specific Antigen (PSA) recurrence compared to a non-robotic surgery for removing the cancerous prostate. Time to PSA recurrence is an example of a survival time that is typically interval-censored between two consecutive clinical inspections with opposite test results. In addition, success of medical devices and technologies often depends on factors such as experience and skill level of the medical service providers, thus leading to clustering of these survival times. For analyzing the effects of surgery types and other covariates on median of clustered interval-censored time to post-surgery PSA recurrence, we present three competing novel models and associated frequentist and Bayesian analyses. The first model is based on a transform-both-sides of survival time with Gaussian random effects to account for the within-cluster association. Our second model assumes an approximate marginal Laplace distribution for the transformed log-survival times with a Gaussian copula to accommodate clustering. Our third model is a special case of the second model with Laplace distribution for the marginal log-survival times and Gaussian copula for the within-cluster association. Simulation studies establish the second model to be highly robust against extreme observations while estimating median regression coefficients. We provide a comprehensive comparison among these three competing models based on the model properties and the computational ease of their Frequentist and Bayesian analysis. We also illustrate the practical implementations and uses of these methods via analysis of a simulated clustered interval-censored data-set similar in design to a post-surgery PSA recurrence study.


Asunto(s)
Antígeno Prostático Específico , Próstata , Teorema de Bayes , Análisis por Conglomerados , Humanos , Masculino , Distribución Normal
6.
AAPS PharmSciTech ; 15(5): 1197-208, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24889733

RESUMEN

Leaching of the internal apolar phase from the biopolymeric microparticles during storage is a great concern as it undoes the beneficial effects of encapsulation. In this paper, a novel formulation was prepared by encapsulating the sunflower oil-based organogels in alginate microparticles. Salicylic acid and metronidazole were used as the model drugs. The microparticles were prepared by double emulsion methodology. Physico-chemical characterization of the microparticles was done by microscopy, FTIR, XRD, and DSC studies. Oil leaching studies, biocompatibility, mucoadhesivity, in vitro drug release, and the antimicrobial efficiency of the microparticles were also performed. The microparticles were found to be spherical in shape. Gelation of the sunflower oil prevented leaching of the internal phase from the microparticles. Release of drugs from the microparticles followed Fickian kinetics and non-Fickian kinetics in gastric and intestinal environments, respectively. Microparticles showed good antimicrobial activity against both Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria. The results suggested that the developed formulations hold promise to carry oils without leakage of the internal phase. Encapsulation of organogels within the microparticles has improved the drug entrapment efficiency and improved characteristics for controlled delivery applications.


Asunto(s)
Alginatos/química , Cápsulas/química , Composición de Medicamentos/métodos , Geles/química , Polisorbatos/química , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Ésteres , Ensayo de Materiales , Metronidazol/administración & dosificación , Metronidazol/química , Tamaño de la Partícula , Ácido Salicílico/administración & dosificación , Ácido Salicílico/química
7.
Int J Biol Macromol ; 256(Pt 1): 128262, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37989431

RESUMEN

This study focused on GSK-3ß, a critical serine/threonine kinase with diverse cellular functions. However, there is limited understanding of the impact of non-synonymous single nucleotide polymorphisms (nsSNPs) on its structure and function. Through an exhaustive in-silico investigation 12 harmful nsSNPs were predicted from a pool of 172 acquired from the NCBI dbSNP database using 12 established tools that detects deleterious SNPs. Consistently, these nsSNPs were discovered in locations with high levels of conservation. Notably, the three harmful nsSNPs F67C, A83T, and T138I were situated in the active/binding site of GSK-3ß, which may affect the protein's capacity to bind to substrates and other proteins. Molecular dynamics simulations revealed that the F67C and T138I mutants had stable structures, indicating rigidness, whereas the A83T mutant was unstable. Analysis of secondary structures revealed different modifications in all mutant forms, which may affect the stability, functioning, and interactions of the protein. These mutations appear to alter the structural dynamics of GSK-3ß, which may have functional ramifications, such as the formation of novel secondary structures and variations in coil-to-helix transitions. In conclusion, this study illuminates the possible structural and functional ramifications of these GSK-3 nsSNPs, revealing how protein compactness, stiffness, and interactions may affect biological activities.


Asunto(s)
Glucógeno Sintasa Quinasa 3 , Polimorfismo de Nucleótido Simple , Glucógeno Sintasa Quinasa 3 beta/genética , Polimorfismo de Nucleótido Simple/genética , Glucógeno Sintasa Quinasa 3/genética , Simulación de Dinámica Molecular , Cicatrización de Heridas , Biología Computacional
8.
Int J Surg ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38869979

RESUMEN

This comprehensive review explores the complex terrain of stem cell therapies as a potential therapeutic frontier in the healing of complicated burn wounds. Serious tissue damage, impaired healing processes, and possible long-term consequences make burn wounds a complex problem. An in-depth review is required since, despite medical progress, existing methods for treating severe burn wounds have significant limitations. Burn wounds are difficult to heal because they cause extensive tissue damage. The challenges of burn injury-induced tissue regeneration and functional recovery are also the subject of this review. Although there is a lot of promise in current stem cell treatments, there are also some limitations with scalability, finding the best way to transport the cells, and finding consistent results across different types of patients. To shed light on how to improve stem cell interventions to heal severe burn wounds, this review covers various stem cell applications in burn wounds and examines these obstacles. To overcome these obstacles, one solution is to enhance methods of stem cell distribution, modify therapies according to the severity of the burn, and conduct more studies on how stem cell therapy affects individual patients. Novel solutions may also be possible through the combination of cutting-edge technologies like nanotechnology and biotechnology. This review seeks to increase stem cell interventions by analyzing present challenges and suggesting strategic improvements. The goal is to provide a more effective and tailored way to repair serious burn wounds.

9.
Int J Biol Macromol ; 261(Pt 1): 129661, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266850

RESUMEN

In this study, a bilayer electrospun scaffold has been prepared using regenerated cellulose (RC)/quaternized chitosan (CS) as the primary layer and collagen/hyaluronic acid (HA) as the second layer. An approximate 48 mol% substituted (estimated from 1H NMR) quaternized CS was used in this study. Both layers were crosslinked with EDC/NHS, reflecting an increase in UTS (2.29 MPa for the bilayer scaffold compared to 1.82 MPa for the RC scaffold). Initial cell viability, cell adhesion and proliferation, FDA staining for live cells, and hydroxyproline release rate from cells were evaluated with L929 mouse fibroblast cells. Also, detailed in vitro studies were performed using HADF cells, which include MTT Assay, Live/Dead imaging, DAPI staining, gene expression of PDGF, VEGF-A, and COL1 in RT-PCR, and cell cycle analysis. The collagen/HA-based bilayer scaffold depicted a 9.76-fold increase of VEGF-A compared to a 2.1-fold increase for the RC scaffold, indicating angiogenesis and vascularization potential. In vitro scratch assay was performed to observe the migration of cells in simulated wounds. Antimicrobial, antioxidant, and protease inhibitory activity were further performed, and overall, the primary results highlighted the potential usage of bilayer scaffold in wound healing applications.


Asunto(s)
Celulosa , Quitosano , Animales , Ratones , Quitosano/química , Ácido Hialurónico , Factor A de Crecimiento Endotelial Vascular , Colágeno/química , Cicatrización de Heridas , Andamios del Tejido/química
10.
Adv Healthc Mater ; : e2402024, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39226530

RESUMEN

In the pursuit of new wound care products, researchers are exploring methods to improve wound healing through exogenous wound healing products. However, diverging from this conventional approach, this work has developed an endogenous support system for wound healing, drawing inspiration from the body's innate healing mechanisms governed by the sequential release of metal ions by body at wound site to promote different stages of wound healing. This work engineers a multi-ion-releasing sprayable hydrogel system, to mimic this intricate process, representing the next evolutionary step in wound care products. It comprises Alginate (Alg) and Fibrin (Fib) hydrogel infused with Polylactic acid (PLA) polymeric microcarriers encapsulating multi (calcium, copper, and zinc) nanoparticles (Alg-Fib-PLA-nCMB). Developed sprayable Alg-Fib-PLA-nCMB hydrogel show sustained release of beneficial multi metallic ions at wound site, offering a range of advantages including enhanced cellular function, antibacterial properties, and promotion of crucial wound healing processes like cell migration, ROS mitigation, macrophage polarization, collagen deposition, and vascular regeneration. In a comparative study with a commercial product (Midstress spray), developed Alg-Fib-PLA-nCMB hydrogel demonstrates superior wound healing outcomes in a rat model, indicating its potential for next generation wound care product, addressing critical challenges and offering a promising avenue for future advancements in the wound management.

11.
Int J Pharm ; 662: 124490, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39032873

RESUMEN

A sodium alginate (Alg) based REDOX (reduction and oxidation)-responsive and fluorescent active microgel was prepared via water in oil (w/o) mini-emulsion polymerization technique. Here, we initially synthesized sodium alginate-based disulfide cross linked microgels and after that those microgels were tagged with rhodamine amine derivative (RhB-NH2) by ionic interaction to get the pH-responsive fluorescent property. Functionalized microgels were characterized using 1H NMR, FTIR, DLS, HRTEM, FESEM, UV-vis, and fluorescence spectroscopy analyses. Presence of the REDOX-responsive disulfide-containing crosslinkers in the microgels enhances the release of doxorubicin (DOX), an anti-cancer drug in the reducing environment of the cancer-cells (simulated). Existence of the rhodamine-amine derivative in the microgels triggers the pH-dependent fluorescence property by showing fluorescence emission at 560-580 nm at pH 5.5 (cancer cell pH). The cytotoxicity of the biopolymer based microgel was assessed over both cancerous HeLa (IC50 100 µg/mL) and non-cancerous MDCK (IC50 200 µg/mL) cells by MTT assay which showed the synthesized microgel is non-toxic whereas DOX-loaded microgels showed significant toxicity. FACS and cell uptake (in vitro) analyses were conducted to understand the cell apoptosis cycle and behavior of the cancer cells in presence of the DOX-loaded microgels. This pH-responsive fluorescent active alginate-based biomaterial could be a promising material for the anti-cancer drug delivery and other medical fields.


Asunto(s)
Alginatos , Doxorrubicina , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Microgeles , Oxidación-Reducción , Alginatos/química , Concentración de Iones de Hidrógeno , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Doxorrubicina/química , Humanos , Células HeLa , Animales , Microgeles/química , Sistemas de Liberación de Medicamentos/métodos , Perros , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Rodaminas/química , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Colorantes Fluorescentes/química
12.
Artículo en Inglés | MEDLINE | ID: mdl-37850546

RESUMEN

BACKGTOUND: The interconnection between different fields of research has gained interest due to its cutting-edge perspectives in solving scientific problems. Terminalia arjuna is indigenously used in India for curing several diseases and its pharmacological activities are being revisited in recent drug-repurposing researches. OBJECTIVE: Efficient ultrasound-assisted extraction of phytochemicals from the bark of Terminalia arjuna is highlighted in this study. Following the optimization of the extraction process, the crude hydroethanolic extract is subjected to phytochemical profiling and an in-silico investigation on its anti-cancer property. METHODOLOGY: A three-level four-factor Box-Behnken design is exploited to optimize four operational parameters namely extraction time, ultrasonic power, ethanol concentration (as the extracting solvent) and solute (in g) : solvent (in mL) ratio. At the optimum parametric condition, the crude extract is obtained and its GC-MS analysis is done. An analysis of network pharmacology (by constructing and visualizing biological networks using Cytoscape) combined with molecular docking reveals the potential antineoplastic targets of the crude extract. RESULTS: The ANOVA table exhibits the significance, adequacy and reliability of the proposed second-order polynomial model with a R² value of 0.917 and adjusted R² of 0.865. Experimental results portray significant antioxidant potential of the prepared extract in its crude form. The GC-MS analysis of the crude extract predicts the extracted phytochemicals while the constructed biological networks highlight its multi-targeted activity in colorectal cancer. CONCLUSION: The study identifies three phytochemicals viz. luteolin, ß-sitosterol and arjunic acid as potent anti-cancer agents and can be extended with in-vitro and in-vivo experiments to validate the in-silico results, thus establishing lead phytochemicals in multi-targeted colorectal cancer therapies with minimal side effects.

13.
J Biomater Sci Polym Ed ; 34(18): 2483-2497, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37768865

RESUMEN

Biocompatible nanoparticles are very popular in health science research. Biomolecule carriers for wound healing and tissue engineering are two main applications among many others. In many instances, these structures come in direct vicinity of cells and govern cell behaviour and responses. In this study, gelatin nano/submicron structures were synthesized by binary nonsolvent aided coacervation (BNAC) method at pH ranging from 3 to 11 with an intention to employ in skin tissue regeneration. Effect of pH over morphology and the surface composition with respect to its ionic composition were studied. Further, the initial toxicity was assessed against peripheral blood mononuclear cells (PBMC). pH 7 was found to be the optimum for synthesis of gelatin nanoparticles (GNPs) with minimum particle size. Positive cell viability of 103.14% for GNPs synthesized at pH 7 was observed. It may be due to the minimum difference between cumulative negative and positive charge (CNCP) ratio of 1.19. Finally, effect of the gelatin nanoparticles over L929 mouse fibroblast cells was assessed through MTT assay. It has resulted in 122.77% cell viability.


Asunto(s)
Gelatina , Nanopartículas , Ratones , Animales , Gelatina/química , Leucocitos Mononucleares , Nanopartículas/química , Piel , Células del Estroma
14.
Burns Trauma ; 11: tkac058, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36761088

RESUMEN

Background: Biomaterials are vital products used in clinical sectors as alternatives to several biological macromolecules for tissue engineering techniques owing to their numerous beneficial properties, including wound healing. The healing pattern generally depends upon the type of wounds, and restoration of the skin on damaged areas is greatly dependent on the depth and severity of the injury. The rate of wound healing relies on the type of biomaterials being incorporated for the fabrication of skin substitutes and their stability in in vivo conditions. In this review, a systematic literature search was performed on several databases to identify the most frequently used biomaterials for the development of successful wound healing agents against skin damage, along with their mechanisms of action. Method: The relevant research articles of the last 5 years were identified, analysed and reviewed in this paper. The meta-analysis was carried out using PRISMA and the search was conducted in major scientific databases. The research of the most recent 5 years, from 2017-2021 was taken into consideration. The collected research papers were inspected thoroughly for further analysis. Recent advances in the utilization of natural and synthetic biomaterials (alone/in combination) to speed up the regeneration rate of injured cells in skin wounds were summarised. Finally, 23 papers were critically reviewed and discussed. Results: In total, 2022 scholarly articles were retrieved from databases utilizing the aforementioned input methods. After eliminating duplicates and articles published before 2017, ~520 articles remained that were relevant to the topic at hand (biomaterials for wound healing) and could be evaluated for quality. Following different procedures, 23 publications were selected as best fitting for data extraction. Preferred Reporting Items for Systematic Reviews and Meta-Analyses for this review illustrates the selection criteria, such as exclusion and inclusion parameters. The 23 recent publications pointed to the use of both natural and synthetic polymers in wound healing applications. Information related to wound type and the mechanism of action has also been reviewed carefully. The selected publication showed that composites of natural and synthetic polymers were used extensively for both surgical and burn wounds. Extensive research revealed the effects of polymer-based biomaterials in wound healing and their recent advancement. Conclusions: The effects of biomaterials in wound healing are critically examined in this review. Different biomaterials have been tried to speed up the healing process, however, their success varies with the severity of the wound. However, some of the biomaterials raise questions when applied on a wide scale because of their scarcity, high transportation costs and processing challenges. Therefore, even if a biomaterial has good wound healing qualities, it may be technically unsuitable for use in actual medical scenarios. All of these restrictions have been examined closely in this review.

15.
ACS Biomater Sci Eng ; 9(8): 4673-4685, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37399249

RESUMEN

In this work, a titanium-doped hydroxyapatite (HAp) scaffold was produced from two different sources (natural eggshell and laboratory-grade reagents) to compare the efficacy of natural and synthetic resources of HAp materials on new bone regeneration. This comparative study also reports the effect of Ti doping on the physical, mechanical, and in vitro as well as in vivo biological properties of the HAp scaffold. Pellets were prepared in the conventional powder metallurgy route, compacted, and sintered at 900 °C, showing sufficient porosity for bony ingrowth. The physical-mechanical characterizations were performed by density, porosity evaluation, XRD, FTIR, SEM analysis, and hardness measurement. In vitro interactions were evaluated by bactericidal assay, hemolysis, MTT assay, and interaction with simulated body fluid. All categories of pellets showed absolute nonhemolytic and nontoxic character. Furthermore, significant apatite formation was observed on the Ti-doped HAp samples in the simulated body fluid immersion study. The developed porous pellets were implanted to assess the bone defect healing in the femoral condyle of healthy rabbits. A 2 month study after implantation showed no marked inflammatory reaction for any samples. Radiological analysis, histological analysis, SEM analysis, and oxytetracycline labeling studies depicted better invasion of mature osseous tissue in the pores of doped eggshell-derived HAp scaffolds as compared to the undoped HAp, and laboratory-made samples. Quantification using oxytetracycline labeling depicted 59.31 ± 1.89% new bone formation for Ti-doped eggshell HAp as compared to Ti-doped pure HAp (54.41 ± 1.93) and other undoped samples. Histological studies showed the presence of abundant osteoblastic and osteoclastic cells in Ti-doped eggshell HAp in contrast to other samples. Radiological and SEM data also showed similar results. The results indicated that Ti-doped biosourced HAp samples have good biocompatibility, new bone-forming ability, and could be used as a bone grafting material in orthopedic surgery.


Asunto(s)
Durapatita , Oxitetraciclina , Animales , Conejos , Durapatita/farmacología , Titanio/farmacología , Cáscara de Huevo , Regeneración Ósea , Modelos Animales
16.
Phys Eng Sci Med ; 45(2): 601-612, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35575961

RESUMEN

Finding components from multi-channel EEG signal for localizing and detection of onset of seizure, is a new approach in biomedical signal analysis. Tensor-based approaches are utilized to fit the components into multi-dimensional arrays in recent works. We initially decompose EEG signals into Beta band using discrete wavelet transform (DWT). We compare patient templates with normal template for cross-wavelet analysis to obtain Wavelet cross spectrum (WCS) and Wavelet cross coherence coefficients. Next we apply parallel factorization (PARAFAC) modeling, a three-way tensor-based representation in channel, frequency and time-points dimensions on features. Finally, we utilize the ensemble classifier for detecting seizure-free, onset and seizure classes. The clinical dataset for this work comprises of 5 normal subjects and 6 epileptiform patients. The classification performances of WCS features on PARAFAC model for Seizure detection using Ensemble Bagged-Trees classifier obtains 82.21% accuracy, while for Wavelet Coherence features, it provides higher 84.76% accuracy. The results have been compared with well-known Fine Gaussian SVM, Weighted KNN and Ensemble Subspace KNN classifiers. The aim is to analyze data over three dimensions namely, time, frequency and space (channels). This EEG based analysis is significant and effective as an automatic method for detection of seizure before its actual manifestation.


Asunto(s)
Electroencefalografía , Epilepsia , Algoritmos , Electroencefalografía/métodos , Epilepsia/diagnóstico por imagen , Humanos , Convulsiones/diagnóstico por imagen , Análisis de Ondículas
17.
Comput Biol Med ; 141: 105052, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34836625

RESUMEN

BACKGROUND: Aloe vera extract and its bioactive compounds possess anti-proliferative properties against cancer cells. However, no detailed molecular mechanism of action studies has been reported. We have now employed a computational approach to scrutinize the molecular mechanism of lead bioactive compounds from Aloe vera that potentially inhibit DNA synthesis. METHODS: Initially, the anti-proliferative activity of Aloe vera extract was examined in human breast cancer cells (in vitro/in vivo). Later on, computational screening of bioactive compounds from Aloe vera targeting DNA was performed by molecular docking and molecular dynamics simulation. RESULTS: In-vitro and in-vivo studies confirm that Aloe vera extract effectively suppresses the growth of breast cancer cells without significant cytotoxicity towards non-cancerous normal immortal cells. Computational screening predicts that growth suppression may be due to the presence of DNA intercalating bioactive compounds (riboflavin, daidzin, aloin, etc.) contained in Aloe vera. MM/PBSA calculation showed that riboflavin has a higher binding affinity at the DNA binding sites compared to standard drug daunorubicin. CONCLUSIONS: These observations support the hypothesis that riboflavin may be exploited as an anti-proliferative DNA intercalating agent to prevent cancer and is worthy of testing for the management of cancer by performing more extensive pre-clinical and if validated clinical trials.


Asunto(s)
Aloe , Neoplasias , Aloe/química , ADN , Humanos , Simulación del Acoplamiento Molecular , Extractos Vegetales/farmacología
18.
J Biomol Struct Dyn ; 39(16): 6265-6280, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32705952

RESUMEN

The recent outbreak of the coronavirus disease COVID-19 is putting the world towards a great threat. A recent study revealed COVID-19 main protease (Mpro) is responsible for the proteolytic mutation of this virus and is essential for its life cycle. Thus inhibition of this protease will eventually lead to the destruction of this virus. In-Silico Molecular docking was performed with the Native ligand and the 15 flavonoid based phytochemicals of Calendula officinals to check their binding affinity towards the COVID-19 main protease. Finally, the top 3 compounds with the highest affinity have been chosen for molecular dynamics simulation to analyses their dynamic properties and conformational flexibility or stability. In-Silico Docking showed that major phytochemicals of Calendula officinals i.e. rutin, isorhamnetin-3-O-ß-D, calendoflaside, narcissin, calendulaglycoside B, calenduloside, calendoflavoside have better binding energy than the native ligand (inhibitor N3). MD simulation of 100 ns revealed that all the protease-ligand docked complexes are overall stable as compare to Mpro-native ligand (inhibitor N3) complex. Overall, rutin and caledoflaside showed better stability, compactness, and flexibility. Our in silico (Virtual molecular docking and Molecular dynamics simulation) studies pointed out that flavonoid based phytochemicals of calendula (rutin, isorhamnetin-3-O-ß-D, calendoflaside) may be highly effective for inhibiting Mpro which is the main protease for SARS-CoV-2 causing the deadly disease COVID-19. Rutin is already used as a drug and the other two compounds can be made available for future use. Thus the study points a way to combat COVID-19 by the use of major flavonoid based phytochemicals of Calendula officinals. Communicated by Ramaswamy H. Sarma.


Asunto(s)
COVID-19 , Calendula , Flavonoides , Humanos , Simulación del Acoplamiento Molecular , Péptido Hidrolasas , Fitoquímicos , Inhibidores de Proteasas , SARS-CoV-2
19.
Biomed Eng Lett ; 11(1): 25-37, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33747601

RESUMEN

ABSTRACT: Hypopharyngeal tissue engineering is increasing rapidly in this developing world. Tissue damage or loss needs the replacement by another biological or synthesized membrane using tissue engineering. Tissue engineering research is emerging to provide an effective solution for damaged tissue replacement. Polyurethane in tissue engineering has successfully been used to repair and restore the function of damaged tissues. In this context, Can polyurethane be a useful material to deal with hypopharyngeal tissue defects? To explore this, here ester diol based polyurethane (PU) was synthesized in two steps: firstly, polyethylene glycol 400 (PEG 400) was reacted with lactic acid to prepare ester diol, and then it was polymerized with hexamethylene diisocyanate. The physical, mechanical, and biological testing was done to testify the characterization of the membrane. The morphology of the synthesized membrane was investigated by using field emission scanning electron microscopy. Functional groups of the obtained membrane were characterized by fourier transform infrared spectroscopy spectroscopy. Several tests were performed to check the in vitro and in vivo biocompatibility of the membrane. A highly connected homogeneous network was obtained due to the appropriate orientation of a hard segment and soft segment in the synthesized membrane. Mechanical property analysis indicates the membrane has a strength of 5.15 MPa and strain 124%. The membrane showed high hemocompatibility, no cytotoxicity on peripheral blood mononuclear cell, and susceptible to degradation in simulated body fluid solution. Antimicrobial activity assessment has shown promising results against clinically significant bacteria. Primary hypopharyngeal cell growth on the PU membrane revealed the cytocompatibility and subcutaneous implantation on the back of Wistar rats were given in vivo biocompatibility of the membrane. Therefore, the synthesized material can be considered as a potential candidate for a hypopharyngeal tissue engineering application.

20.
J Mater Chem B ; 9(24): 4873-4894, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34095925

RESUMEN

The use of decellularized native allogenic or xenogenic cartilaginous extracellular matrix (ECM) biomaterials is widely expanding in the fields of tissue engineering and regenerative medicine. In this study, we aimed to develop an acellular, affordable, biodegradable, easily available goat conchal cartilaginous ECM derived scaffolding biomaterial for repair and regeneration of osteochondral defects in rabbits. Cartilages harvested from freshly collected goat ears were decellularized using chemical agents, namely, hypotonic-hypertonic (HH) buffer and Triton X-100 solution, separately. The morphologies and ultrastructure orientations of the decellularized cartilages remained unaltered in spite of complete cellular loss. Furthermore, when the acellular cartilaginous ECMs were cultured with murine mesenchymal stem cells (MSCs) (C3H10T1/2 cells), cellular infiltration and proliferation were thoroughly monitored using SEM, DAPI and FDA stained images, whereas the MTT assay proved the biocompatibility of the matrices. The increasing amounts of secreted ECM proteins (collagen and sGAG) indicated successful chondrogenic differentiation of the MSCs in the presence of the treated cartilage samples. In vivo biocompatibility studies showed no significant immune response or tissue rejection in the treated samples but tissue necrosis in control samples after 3 months. Upon implantation of the constructs in rabbits' osteochondral defects for 3 months, the histological and micro-CT evaluation revealed significant enhancement and regeneration of neocartilage and subchondral bony tissues. The IGF-1 loaded cartilaginous constructs showed comparatively better healing response after 3 months. Our results showed that decellularized xenogenic cartilaginous biomaterials preserved the bioactivity and integrity of the matrices that also favored in vitro stem cell proliferation and chondrogenic differentiation and enabled osteochondral regeneration, thus paving a new way for articular cartilage reconstruction.


Asunto(s)
Cartílago Articular/citología , Cartílago Articular/fisiología , Condrogénesis , Matriz Extracelular/metabolismo , Ingeniería de Tejidos , Andamios del Tejido/química , Animales , Diferenciación Celular , Células Madre Mesenquimatosas/citología , Ratones , Conejos
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