Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros

Métodos Terapêuticos e Terapias MTCI
Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Sensors (Basel) ; 22(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36365824

RESUMO

Classification of motor imagery (MI) tasks provides a robust solution for specially-abled people to connect with the milieu for brain-computer interface. Precise selection of uniform tuning parameters of tunable Q wavelet transform (TQWT) for electroencephalography (EEG) signals is arduous. Therefore, this paper proposes robust TQWT for automatically selecting optimum tuning parameters to decompose non-stationary EEG signals accurately. Three evolutionary optimization algorithms are explored for automating the tuning parameters of robust TQWT. The fitness function of the mean square error of decomposition is used. This paper also exploits channel selection using a Laplacian score for dominant channel selection. Important features elicited from sub-bands of robust TQWT are classified using different kernels of the least square support vector machine classifier. The radial basis function kernel has provided the highest accuracy of 99.78%, proving that the proposed method is superior to other state-of-the-art using the same database.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Análise de Ondaletas , Imagens, Psicoterapia , Algoritmos , Máquina de Vetores de Suporte , Processamento de Sinais Assistido por Computador
2.
Pharmacogn Mag ; 13(Suppl 2): S224-S229, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28808384

RESUMO

BACKGROUND: Smithia conferta Sm. is an annual herb widely used in Indian traditional medical practice and commonly known as "Lakshman booti" in Sanskrit. Morphological resemblance among the species of genus Smithia Aiton. leads to inaccurate identification and adulteration. This causes inconsistent therapeutic effects and also affects the quality of herbal medicine. AIM: This study aimed to generate potential barcode for authentication of S. conferta and its adulterants through DNA barcoding technique. MATERIALS AND METHODS: Genomic DNA extracted from S. conferta and its adulterants was used as templates for polymerase chain reaction amplification of the barcoding regions. The amplicons were directed for sequencing, and species identification was conducted using BLASTn and unweighted pair-group method with arithmetic mean trees. In addition, the secondary structures of internal transcribed spacer (ITS) 2 region were predicted. RESULTS: The nucleotide sequence of ITS provides species-specific single nucleotide polymorphisms and sequence divergence (22%) than psbA-trnH (10.9%) and rbcL (3.1%) sequences. The ITS barcode indicates that S. conferta and Smithia sensitiva are closely related compared to other species. CONCLUSION: ITS is the most applicable barcode for molecular authentication of S. conferta, and further chloroplast barcodes should be tested for phylogenetic analysis of genus Smithia. SUMMARY: The present investigation is the first effort of utilization of DNA barcode for molecular authentication of S. conferta and its adulterants. Also, this study expanded the application of the ITS2 sequence data in the authentication. The ITS has been proved as a potential and reliable candidate barcode for the authentication of S. conferta. Abbreviations used: BLASTn: Basic Local Alignment Search Tool for Nucleotide; MEGA: Molecular Evolutionary Genetic Analysis; EMBL: European Molecular Biology Laboratory; psbA-trnH: Photosystem II protein D1- stuctural RNA: His tRNA gene; rbcL: Ribulose 1,5 bi-phosphate carboxylase/oxygenase large subunit gene.

3.
Pharmacogn Mag ; 12(Suppl 1): S32-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27041855

RESUMO

BACKGROUND: Genus Swertia is valued for its great medicinal potential, mainly Swertia chirayita (Roxb. ex Fleming) H. Karst. is used in traditional medicine for a wide range of diseases. Mangiferin one of xanthoids is referred with enormous pharmacological potentials. OBJECTIVE: The aim of the study was to quantify and compare the anticancerous and antidiabetic drug mangiferin from 11 Swertia species from India. The study also evaluates hierarchical relationships between the species based on mangiferin content using multivariate analysis. MATERIALS AND METHODS: The reverse phase-ultra flow liquid chromatography-diode array detector analyses was performed and chromatographic separation was achieved on a Lichrospher 100, C18e (5 µm) column (250-4.6 mm). Mobile phase consisting of 0.2% triethylamine (pH-4 with O-phosphoric acid) and acetonitrile (85:15) was used for separation with injection volume 20 µL and detection wave length at 257 nm. RESULTS: Results indicated that concentration of mangiferin has been found to vary largely between Swertia species collected from different regions. Content of mangiferin was found to be highest in Swertia minor compared to other Swertia species studied herein from the Western Ghats and Himalayan region also. The same was also evident in the multivariate analysis, wherein S. chirayita, S. minor and Swertia paniculata made a separate clade. CONCLUSION: Conclusively, the work herein provides insights of mangiferin content from 11 Swertia species of India and also presents their hierarchical relationships. To best of the knowledge this is the first report of higher content of mangiferin from any Swertia species. SUMMARY: The present study quantifies and compares mangiferin in 11 species of Swertia from India. The study also evaluates hierarchical relationships between the species based on mangiferin content using multivariate analysis. The mangiferin content was highest in S. minor compared to the studied Swertia species. To the best of our knowledge this is the first report of higher content of mangiferin from Swertia species. Abbreviations used: LOD: Limit of detection, LOQ: Limit of quantification, RP-UFLC-DAD: Reverse phase-ultra flow liquid chromatography-diode array detector, RSD: Relative standard deviation, SAN: Swertia angustifolia, SAP: Swertia angustifolia var. pulchella, SBI: S. bimaculata, SCH: S. chirayita, SCO: S. corymbosa, SDE: S. densifolia, SDI: S. dialatata, SLA: S. lawii, SMI: S. minor; SNE: S. nervosa, and SPA: S. paniculata.

4.
Nat Prod Res ; 30(7): 865-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26299409

RESUMO

Genus Swertia is valued for its great medicinal potential; mainly Swertia chirayita (Roxb. ex Fleming) H. Karst. is used in traditional medicine for a wide range of diseases. Seco-iridoid glycosides like swertiamarin is referred with enormous pharmacological potentials. The aim of the study was to identify a suitable substitute to S. chirayita by quantifying seco-iridoid swertiamarin from five different Swertia species endemic to the Western Ghats. The reverse-phase high-performance liquid chromatography diode array detector analyses were performed and chromatographic separation was achieved on a Lichrospher 100, C18e (5 µm) column (250-4.6 mm). A mobile phase consisting of acetonitrile and water (25:75) was used for separation. Results indicated that the concentration of the marker compound has been found to vary largely between and within the species from different localities. The content of swertiamarin was the highest in S. chirayita compared to the other species studied herein, advocating the use of Swertia minor as an alternate source to S. chirayita.


Assuntos
Glucosídeos Iridoides/química , Pironas/química , Swertia/química , Cromatografia Líquida de Alta Pressão , Índia , Glucosídeos Iridoides/isolamento & purificação , Pironas/isolamento & purificação , Swertia/classificação
5.
Nat Prod Res ; 29(19): 1783-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25613495

RESUMO

Aim of this study was to identify pentacyclic triterpenoids betulinic acid (BA), oleanolic acid (OA) and ursolic acid (UA) from five Swertia species endemic to Western Ghats, which are used as substitutes as well as adulterants to Swertia chirayita. Our results indicate that the concentration of active compound vary largely among and within the species from different localities. OA was found in a higher amount in all species compared to BA and UA. From the results, it was clear that BA, OA and UA are present in the endemic species collected from Western Ghats, thus advocating the use of these species as alternate sources to S. chirayita. This in due course may release pressure of exploitation from natural resources of S. chirayita and help to bring it out from an endangered category from conservation point of view.


Assuntos
Ácido Oleanólico/química , Swertia/química , Triterpenos/química , Cromatografia Líquida de Alta Pressão , Índia , Estrutura Molecular , Ácido Oleanólico/isolamento & purificação , Triterpenos Pentacíclicos , Plantas Medicinais/química , Especificidade da Espécie , Swertia/classificação , Triterpenos/isolamento & purificação , Ácido Betulínico , Ácido Ursólico
6.
Biotechnol Rep (Amst) ; 6: 79-84, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28626699

RESUMO

Highly efficient in vitro regeneration system has been developed for Swertia lawii Burkill, an important herb used as substitute for Swertia chirayita. Shoot tips explants were cultured on MS medium with various phytohormones for multiple shoot production. The best shoot production frequency (100%) and maximum shoots (10.4 ± 0.8) were obtained on MS media containing TDZ (3.0 mg l-1) in combination with IBA (0.3 mg l-1). Maximum callus induction (95 ± 4.8%) and callus growth (1.7 ± 0.4 gm) was achieved on MS medium with 2, 4-D (3.0 mg l-1). Cell suspension cultures were established and studied for their growth kinetics. Shoots were rooted best (22.1 ± 2.5) in 1/2 MS medium with IAA (3.0 mg l-1). The genetic uniformity of the micropropagated clones was assessed using RAPD markers. Out of 405 bands, 400 (98.76%) were monomorphic and rest 5 (1.24%) were polymorphic. High multiplication frequency and low risk of genetic instability ensures the efficacy of this protocol.

7.
Nat Prod Res ; 29(8): 780-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25482162

RESUMO

Swertia chirayita is one of the potential medicinal plants of the family Gentianaceae in traditional medicine. Due to its high demand and scarcity, trade of chirayita is affected by adulterants. Swertia species from Western Ghats were compared with S. chirayita for phytochemical characterisation and antioxidant activities by using different extracts. This study revealed that acetone is the best extraction solvent of phenolic and flavonoid compounds with antioxidant properties as compared with other extracts. S. chirayita showed better antioxidant activity than other species with highest content of phenolics and flavonoids. Among the species from Western Ghats, Swertia minor has better antioxidant properties with higher content of phenolics and flavonoids when compared with S. chirayita. Gallic acid was detected in all species under study by using HPLC analysis. The Swertia species under study showed similar phytochemical properties and antioxidant potential and hence their use as substitute to S. chirayita needs to be further investigated.


Assuntos
Antioxidantes/química , Compostos Fitoquímicos/análise , Swertia/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Fenóis/química , Extratos Vegetais/química , Plantas Medicinais/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA