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1.
Artículo en Inglés | MEDLINE | ID: mdl-38837017

RESUMEN

The field of EEG-Neurofeedback (EEG-NF) training has showcased significant promise in treating various mental disorders, while also emerging as a cognitive enhancer across diverse applications. The core principle of EEG-NF involves consciously guiding the brain in desired directions, necessitating active engagement in neurofeedback (NF) tasks over an extended period. Music listening tasks have proven to be effective stimuli for such training, influencing emotions, mood, and brainwave patterns. This has spurred the development of musical NF systems and training protocols. Despite these advancements, there exists a gap in systematic literature that comprehensively explores and discusses the various modalities of feedback mechanisms, its benefits, and the emerging applications. Addressing this gap, our review article presents a thorough literature survey encompassing studies on musical NF conducted over the past decade. This review highlights the several benefits and applications ranging from neurorehabilitation to therapeutic interventions, stress management, diagnostics of neurological disorders, and sports performance enhancement. While acknowledged for advantages and popularity of musical NF, there is an opportunity for growth in the literature in terms of the need for systematic randomized controlled trials to compare its effectiveness with other modalities across different tasks. Addressing this gap will involve developing standardized methodologies for studying protocols and optimizing parameters, presenting an exciting prospect for advancing the field.

2.
PLoS One ; 18(12): e0291949, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38064473

RESUMEN

Pigeonpea (Cajanuscajan L.) is a legume crop that contains high levels of polyphenolic compounds and polysaccharides that become a hindrance in extracting good-quality and enough amount of RNA from its tissues. With the existing methods of RNA isolation, the phenolic compounds may co-precipitate or bind to the RNA giving false results. Therefore, in the present study, we have modified conventional CTAB and Trizol-based methods which resulted in good quality with the absorbance A260/A280 ratios in the range of 1.83 to 1.98 and A260/230 ratios in the range of 2.0-2.23, revealed RNA to be of high purity and free of contaminants. Both of the proposed protocols yielded a good quantity of RNA ranging from 289 to 422µg per gram of tissue. Distinctly visible bands of 28S and 18S rRNA were observed without degradation or smear, which indicated the presence of intact RNA. RT-PCR analysis showed that isolated RNA was quantitatively sufficient and compliant for the subsequent gene expression analysis.


Asunto(s)
Polifenoles , ARN , Cetrimonio , Peso Molecular , Polisacáridos
3.
Org Lett ; 25(43): 7906-7910, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37875402

RESUMEN

Herein, we report the synthesis of π-conjugation-extended vinyl sulfoxonium ylides from vinyl sulfoxonium ylide and electron-deficient alkynes. The new dienoate ylides are used in various transformations, such as X-H (X = S, O) insertion, halogenation, carbene-mediated transformation, and radical-mediated reductions to obtain a variety of conjugated dienoates.

4.
BMC Genomics ; 24(1): 526, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37674140

RESUMEN

To combat drought stress in rice, a major threat to global food security, three major quantitative trait loci for 'yield under drought stress' (qDTYs) were successfully exploited in the last decade. However, their molecular basis still remains unknown. To understand the role of secondary regulation by miRNA in drought stress response and their relation, if any, with the three qDTYs, the miRNA dynamics under drought stress was studied at booting stage in two drought tolerant (Sahbaghi Dhan and Vandana) and one drought sensitive (IR 20) cultivars. In total, 53 known and 40 novel differentially expressed (DE) miRNAs were identified. The primary drought responsive miRNAs were Osa-MIR2919, Osa-MIR3979, Osa-MIR159f, Osa-MIR156k, Osa-MIR528, Osa-MIR530, Osa-MIR2091, Osa-MIR531a, Osa-MIR531b as well as three novel ones. Sixty-one target genes that corresponded to 11 known and 4 novel DE miRNAs were found to be co-localized with the three qDTYs, out of the 1746 target genes identified. We could validate miRNA-mRNA expression under drought for nine known and three novel miRNAs in eight different rice genotypes showing varying degree of tolerance. From our study, Osa-MIR2919, Osa-MIR3979, Osa-MIR528, Osa-MIR2091-5p and Chr01_11911S14Astr and their target genes LOC_Os01g72000, LOC_Os01g66890, LOC_Os01g57990, LOC_Os01g56780, LOC_Os01g72834, LOC_Os01g61880 and LOC_Os01g72780 were identified as the most promising candidates for drought tolerance at booting stage. Of these, Osa-MIR2919 with 19 target genes in the qDTYs is being reported for the first time. It acts as a negative regulator of drought stress tolerance by modulating the cytokinin and brassinosteroid signalling pathway.


Asunto(s)
MicroARNs , Oryza , Sequías , Oryza/genética , Sitios de Carácter Cuantitativo , Resistencia a la Sequía , MicroARNs/genética
5.
Front Microbiol ; 14: 1196101, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37465020

RESUMEN

Population explosions, environmental deprivation, and industrial expansion led to an imbalanced agricultural system. Non-judicial uses of agrochemicals have decreased agrodiversity, degraded agroecosystems, and increased the cost of farming. In this scenario, a sustainable agriculture system could play a crucial role; however, it needs rigorous study to understand the biological interfaces within agroecosystems. Among the various biological components with respect to agriculture, mycorrhizae could be a potential candidate. Most agricultural crops are symbiotic with arbuscular mycorrhizal fungi (AMF). In this study, beetroot has been chose to study the effect of different AMFs on various parameters such as morphological traits, biochemical attributes, and gene expression analysis (ALDH7B4 and ALDH3I1). The AMF Gm-Funneliformis mosseae (Glomus mosseae), Acaulospora laevis, and GG-Gigaspora gigantean were taken as treatments to study the effect on the above-mentioned parameters in beetroot. We observed that among all the possible combinations of mycorrhizae, Gm+Al+GG performed best, and the Al-alone treatment was found to be a poor performer with respect to all the studied parameters. This study concluded that the more the combinations of mycorrhizae, the better the results will be. However, the phenomenon depends on the receptivity, infectivity, and past nutrient profile of the soil.

6.
Stud Health Technol Inform ; 305: 81-84, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37386963

RESUMEN

In this study, we analyzed the utility of electromyogram (EMG) signals recorded from the zygomaticus major (zEMG), the trapezius (tEMG), and the corrugator supercilii (cEMG) for emotion detection. We computed eleven-time domain features from the EMG signals to classify the emotions such as amusing, boring, relaxing, and scary. The features were fed to the logistic regression, support vector machine, and multilayer perceptron classifiers, and model performance was evaluated. We achieved an average 10-fold cross-validation classification accuracy of 67.29%. 67.92% and 64.58% by LR using the features extracted from the EMG signals recorded from the zEMG, tEMG, and cEMG, respectively. The classification accuracy improved to 70.6% while combining features from the zEMG and cEMG for the LR model. However, the performance dropped while including the features of EMG from all three locations. Our study shows the importance of utilizing the zEMG and cEMG combination for emotion recognition.


Asunto(s)
Emociones , Cara , Electromiografía , Modelos Logísticos , Miedo
7.
Org Lett ; 24(45): 8359-8363, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36342368

RESUMEN

Herein, we report carbene-mediated benzannulation of vinyl sulfoxonium ylides with electron-deficient alkynes and alkenes to synthesize oxygenated arenes. This protocol features excellent regioselectivity, a broad substrate scope, and mild reaction conditions. Mechanistic studies revealed that the reaction proceeds through furan generation, cycloaddition, ring cleavage, and aromatization cascades. The synthesized arenes have been utilized in diverse product transformations and arene ring homologation.

8.
J Equine Vet Sci ; 115: 104020, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35605881

RESUMEN

The pharmacokinetics of ampicillin-cloxacillin, given as single intravenously dose of 10 mg.kg-1 (5 mg.kg-1 of ampicillin plus 5 mg.kg-1 of cloxacillin) was examined in clinically presented Indian thoroughbred horses (n = 6) in order to design appropriate dosing strategies. Drug concentrations in plasma were determined by high performance liquid chromatography (HPLC) and pharmacokinetic parameters were derived by non-compartmental analysis using WinNonlin software. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ampicillin-cloxacillin against quality control strains of Escherichia coli and Staphylococcus aureus, grown in Muller Hinton Broth, were determined by broth microdilution method. For ampicillin, area under plasma drug concentration time curve (AUC) was 15.2 ± 0.54 µg.h.ml-1, mean residence time (MRT) was 1.33 ± 0.06 h and clearance (Cl) was 0.33 ± 0.01 L.h-1.kg-1. For cloxacillin, AUC was 18.0 ± 0.9 µg.h.ml-1, MRT was 1.28 ± 0.02 h and Cl was 0.28 ± 0.01 L.h-1.kg-1. MIC of ampicillin-cloxacillin combination against E. coli and S. aureus was determined to be 0.4 µg.ml-1. PK-PD integration indicated that to maintain %T > MIC value 50% for bacteria with MIC ≤ 0.4 µg.ml-1, an appropriate intravenous dosage regimen of ampicillin-cloxacillin combination in horses would be 15 mg.kg-1 (i.e. 7.5 mg.kg-1 of ampicillin plus 7.5 mg.kg-1 of cloxacillin), to be repeated at 12 h intervals. Safety profile of the recommended regimen did not significantly alter any of the 16 biochemical or haematological parameters studied.


Asunto(s)
Escherichia coli , Staphylococcus aureus , Ampicilina/farmacología , Animales , Antibacterianos/farmacología , Cloxacilina/farmacología , Caballos
9.
Sci Rep ; 11(1): 1320, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33446742

RESUMEN

To obtain deeper insights into the tactile processing pathway from a population-level point of view, we have modeled three stages of the tactile pathway from the periphery to the cortex in response to indentation and scanned edge stimuli at different orientations. Three stages in the tactile pathway are, (1) the first-order neurons which innervate the cutaneous mechanoreceptors, (2) the cuneate nucleus in the midbrain and (3) the cortical neurons of the somatosensory area. In the proposed network, the first layer mimics the spiking patterns generated by the primary afferents. These afferents have complex skin receptive fields. In the second layer, the role of lateral inhibition on projection neurons in the cuneate nucleus is investigated. The third layer acts as a biomimetic decoder consisting of pyramidal and cortical interneurons that correspond to heterogeneous receptive fields with excitatory and inhibitory sub-regions on the skin. In this way, the activity of pyramidal neurons is tuned to the specific edge orientations. By modifying afferent receptive field size, it is observed that the larger receptive fields convey more information about edge orientation in the first spikes of cortical neurons when edge orientation stimuli move across the patch of skin. In addition, the proposed spiking neural model can detect edge orientation at any location on the simulated mechanoreceptor grid with high accuracy. The results of this research advance our knowledge about tactile information processing and can be employed in prosthetic and bio-robotic applications.


Asunto(s)
Mecanorreceptores/fisiología , Bulbo Raquídeo/fisiología , Modelos Neurológicos , Red Nerviosa/patología , Corteza Somatosensorial/fisiología , Tacto/fisiología , Animales , Humanos , Piel/inervación , Fenómenos Fisiológicos de la Piel
10.
Biomed Eng Online ; 18(1): 90, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31455355

RESUMEN

BACKGROUND: Stroke-related sensory and motor deficits often steal away the independent mobility and balance from stroke survivors. Often, this compels the stroke survivors to rely heavily on their non-paretic leg during weight shifting to execute activities of daily living (ADL), with reduced usage of the paretic leg. Increased reliance on non-paretic leg often leads to learned nonuse of the paretic leg. Therefore, it is necessary to measure the contribution of individual legs toward one's overall balance. In turn, techniques can be developed to condition the usage of both the legs during one's balance training, thereby encouraging the hemiplegic patients for increased use of their paretic leg. The aim of this study is to (1) develop a virtual reality (VR)-based balance training platform that can estimate the contribution of each leg during VR-based weight-shifting tasks in an individualized manner and (2) understand the implication of operant conditioning paradigm during balance training on the overall balance of hemiplegic stroke patients. RESULT: Twenty-nine hemiplegic patients participated in a single session of VR-based balance training. The participants maneuvered virtual objects in the virtual environment using two Wii Balance Boards that measured displacement in the center of pressure (CoP) due to each leg when one performed weight-shifting tasks. For operant conditioning, the weight distribution across both the legs was conditioned (during normal trial) to reward participants for increased usage of the paretic leg during the weight-shifting task. The participants were offered multiple levels of normal trials with intermediate catch trial (with equal weight distribution between both legs) in an individualized manner. The effect of operant conditioning during the normal trials was measured in the following catch trials. The participants showed significantly improved performance in the final catch trial compared to their initial catch trial task. Also, the enhancement in CoP displacement of the paretic leg was significant in the final catch trial compared to the initial catch trial. CONCLUSION: The developed system was able to encourage participants for improved usage of their paretic leg during weight-shifting tasks. Such an approach has the potential to address the issue of learned nonuse of the paretic leg in stroke patients.


Asunto(s)
Condicionamiento Operante , Equilibrio Postural/fisiología , Realidad Virtual , Actividades Cotidianas , Adolescente , Adulto , Anciano , Femenino , Hemiplejía/fisiopatología , Hemiplejía/psicología , Hemiplejía/terapia , Humanos , Masculino , Persona de Mediana Edad
11.
IEEE Trans Neural Syst Rehabil Eng ; 25(7): 935-944, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28207400

RESUMEN

Stroke patients usually suffer from asymmetric posture due to hemi-paresis that can result in reduced postural controllability leading to a balance deficit. This deficit increases the risk of falls, which often makes them dependent on caregivers for community ambulation, thus deteriorating their quality of life. Conventional balance training involves rehabilitation exercises performed under physiotherapist's supervision, where the scarcity of trained professionals as well as the cost of clinic-based rehabilitation programs can deter stroke survivors from undergoing regular balance training. Thus, researchers have been exploring technology-assisted solutions, e.g., home-based virtual reality (VR) setup. In this paper, we developed a VR-based balance training (VBaT) platform, where VR-augmented user-interface using Nintendo Wii balance boardwas tested in a laboratory setting for its feasibility. The VBaT offered tasks of varying difficulties to the participants that adapted to individual performance capability during balance training. We performed a preliminaryusability study with 7 stroke survivors (post-stroke period > 6 months). Preliminary results indicate the potential of theVBaT system to cause improvement in overall average task performance over the course of training while using the VBaT. Thus the VBaT system is proposed to be a step toward an effective balance training platform for people with balance disorder.


Asunto(s)
Terapia por Ejercicio/instrumentación , Equilibrio Postural , Rehabilitación de Accidente Cerebrovascular/instrumentación , Accidente Cerebrovascular/fisiopatología , Terapia Asistida por Computador/instrumentación , Adulto , Anciano , Análisis Costo-Beneficio , Diseño de Equipo , Análisis de Falla de Equipo , Terapia por Ejercicio/economía , Terapia por Ejercicio/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Accidente Cerebrovascular/economía , Accidente Cerebrovascular/terapia , Rehabilitación de Accidente Cerebrovascular/economía , Rehabilitación de Accidente Cerebrovascular/métodos , Terapia Asistida por Computador/economía , Terapia Asistida por Computador/métodos , Resultado del Tratamiento , Interfaz Usuario-Computador , Adulto Joven
12.
Artículo en Inglés | MEDLINE | ID: mdl-29359128

RESUMEN

Poststroke hemiplegic patients often show altered weight distribution with balance disorders, increasing their risk of fall. Conventional balance training, though powerful, suffers from scarcity of trained therapists, frequent visits to clinics to get therapy, one-on-one therapy sessions, and monotony of repetitive exercise tasks. Thus, technology-assisted balance rehabilitation can be an alternative solution. Here, we chose virtual reality as a technology-based platform to develop motivating balance tasks. This platform was augmented with off-the-shelf available sensors such as Nintendo Wii balance board and Kinect to estimate one's center of mass (CoM). The virtual reality-based CoM-assisted balance tasks (Virtual CoMBaT) was designed to be adaptive to one's individualized weight-shifting capability quantified through CoM displacement. Participants were asked to interact with Virtual CoMBaT that offered tasks of varying challenge levels while adhering to ankle strategy for weight shifting. To facilitate the patients to use ankle strategy during weight-shifting, we designed a heel lift detection module. A usability study was carried out with 12 hemiplegic patients. Results indicate the potential of our system to contribute to improving one's overall performance in balance-related tasks belonging to different difficulty levels.

13.
Eur J Transl Myol ; 26(2): 6032, 2016 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-27478569

RESUMEN

Stroke is one of leading cause of death and disability worldwide. Early detection during golden hour and treatment of individual neurological dysfunction in stroke using easy-to-access biomarkers based on a simple-to-use, cost-effective, clinically-valid screening tool can bring a paradigm shift in healthcare, both urban and rural. In our research we have designed a quantitative automatic home-based oculomotor assessment tool that can play an important complementary role in prognosis of neurological disorders like stroke for the neurologist. Once the patient has been screened for stroke, the next step is to design proper rehabilitation platform to alleviate the disability. In addition to the screening platform, in our research, we work in designing virtual reality based rehabilitation exercise platform that has the potential to deliver visual stimulation and in turn contribute to improving one's performance.

14.
Eur J Transl Myol ; 26(2): 6030, 2016 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-27478568

RESUMEN

Neurological disorders often manifest themselves in the form of movement deficit on the part of the patient. Conventional rehabilitation often used to address these deficits, though powerful are often monotonous in nature. Adequate audio-visual stimulation can prove to be motivational. In the research presented here we indicate the applicability of audio-visual stimulation to rehabilitation exercises to address at least some of the movement deficits for upper and lower limbs. Added to the audio-visual stimulation, we also use Functional Electrical Stimulation (FES). In our presented research we also show the applicability of FES in conjunction with audio-visual stimulation delivered through VR-based platform for grasping skills of patients with movement disorder.

15.
J Vis Exp ; (110)2016 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-27166666

RESUMEN

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to reorganize its structure, function and connections as a response to intrinsic or extrinsic stimuli is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. Beneficial neuroplastic changes may be facilitated with non-invasive electrotherapy, such as neuromuscular electrical stimulation (NMES) and sensory electrical stimulation (SES). NMES involves coordinated electrical stimulation of motor nerves and muscles to activate them with continuous short pulses of electrical current while SES involves stimulation of sensory nerves with electrical current resulting in sensations that vary from barely perceivable to highly unpleasant. Here, active cortical participation in rehabilitation procedures may be facilitated by driving the non-invasive electrotherapy with biosignals (electromyogram (EMG), electroencephalogram (EEG), electrooculogram (EOG)) that represent simultaneous active perception and volitional effort. To achieve this in a resource-poor setting, e.g., in low- and middle-income countries, we present a low-cost human-machine-interface (HMI) by leveraging recent advances in off-the-shelf video game sensor technology. In this paper, we discuss the open-source software interface that integrates low-cost off-the-shelf sensors for visual-auditory biofeedback with non-invasive electrotherapy to assist postural control during balance rehabilitation. We demonstrate the proof-of-concept on healthy volunteers.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Rehabilitación de Accidente Cerebrovascular/métodos , Estimulación Eléctrica , Electromiografía , Humanos , Accidente Cerebrovascular
16.
IEEE Trans Neural Syst Rehabil Eng ; 24(10): 1051-1059, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26780816

RESUMEN

Eye movements are a continuous and ubiquitous part of sensory perception. To properly generate highly accurate and co-ordinate ocular movements, a vast network of brain areas are engaged, from low-level visual processing to motor control of gaze orientation. This renders oculomotor system vulnerable to various neurological disorders with unique clinical patterns. Therefore, oculomotor examination can serve as an early and sensitive indicator for various neurological conditions. A simple-to-use, clinically valid system for objectively assessing the oculomotor function can thus bring a paradigm shift in diagnosis and treatment of brain disorders. In principal accordance, this paper presents a gaze assessment tool, called SmartEye, which is based on eye fixation, smooth pursuit, and blinking in response to both static and dynamic visual stimuli. The gaze related indices were evaluated in real-time by SmartEye and these were mapped to the reported pathological state in chronic ( > 3 months) patients with stroke. Our preliminary feasibility study with eight pairs of chronic ( > 3 months) stroke survivors and healthy individuals revealed that gaze related indices in response to both static and dynamic visual stimuli may serve as potential quantitative biomarkers for stroke assessment.


Asunto(s)
Diagnóstico por Computador/instrumentación , Técnicas de Diagnóstico Oftalmológico/instrumentación , Fijación Ocular , Trastornos de la Motilidad Ocular/diagnóstico , Trastornos de la Motilidad Ocular/fisiopatología , Músculos Oculomotores/fisiopatología , Algoritmos , Parpadeo , Sistemas de Apoyo a Decisiones Clínicas/organización & administración , Diagnóstico por Computador/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistemas de Atención de Punto , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Programas Informáticos , Interfaz Usuario-Computador
17.
Vet World ; 8(12): 1410-5, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27047053

RESUMEN

AIM: To evaluate the feasibility of C-arm guided closed intramedullary pinning (simple Steinmann and end threaded) techniques for the stabilization of various canine long bone fractures. MATERIALS AND METHODS: The present study was conducted on 19 dogs with long bone fractures which were stabilized using simple Steinmann (Group I; n=6) and end threaded (Group II; n=13) pinning under C-arm guidance. Signalment, history of trauma, clinical examination, and hematobiochemical findings were recorded at the time of presentation. Radiography of the affected limb was carried out in two views to determine type and site of the fracture. Treatment of all the fractures was attempted using simple Steinman and end threaded pinning under the C-arm guidance. The success and failure of the closed technique were correlated with age, site, and type of fractures. RESULTS: The mean body weight and age of the dogs were 18.53±2.18 kg and 21.58±5.85 months, respectively. Early presented cases at a mean day of 2.84±0.54 were included. Out of 19 cases, it was possible to place implant successfully in 10 cases (success rate 52.63%) only. The remaining 9 cases had serious intraoperative complications like a misdirection of the pin after engaging the proximal fragment (n=3), missing the proximal fragment completely, and formation of the false tract (n=6). The majority of these complications were associated with younger age and proximal or distal third oblique fractures. High success rate of C-arm guided closed pinning was observed in midshaft fractures (75%) and transverse fractures (77.78%) in dogs of more than 1 year of age (77.78%). Simple Steinmann pinning was better feasible in a closed manner with a high success rate (66.70%) but also had implant related complications. Although, C-arm guided end threaded pinning was less (46.15%) successful, slightly tedious and time-consuming but had better implant stability than that of simple intramedullary pinning. CONCLUSIONS: From the present study, it was concluded that C-arm guided closed pinning is recommended in transverse and midshaft fractures of the long bones in dogs older than 1 year of age. Furthermore, there is need to improve traction devices for enhancing the success of C-arm guided intramedullary pinning in dogs.

18.
Int J Pharm ; 427(2): 153-62, 2012 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-22306039

RESUMEN

The work was aimed at developing calcium-pectinate matrix tablet for colon-targeted delivery of meloxicam (MLX) microsponges. Modified quassi-emulsion solvent diffusion method was used to formulate microsponges (MS), based on 3(2) full factorial design. The effects of volume of dichloromethane and EudragitRS100 content (independent variables) were determined on the particle size, entrapment efficiency and %cumulative drug release of MS1-MS9. The optimized formulation, MS5 (d(mean)=44.47 µm, %EE=98.73, %CDR=97.32 and followed zero order release) was developed into colon-targeted matrix tablet using calcium pectinate as the matrix. The optimized colon-targeted tablet (MS5T2) shielded MLX loaded microsponges in gastrointestinal region and selectively delivered them to colon, as vizualized by vivo fluoroscopy in rabbits. The pharmacokinetic evaluation of MS5T2 in rabbits, revealed appearance of drug appeared in plasma after a lag time of 7h; a t(max) of 30 h with Fr=61.047%, thus presenting a formulation suitable for targeted colonic delivery. CLSM studies provided an evidence for colonic luminal retentive ability of microsponges at the end of 8h upon oral administration of MS5T2. Thus calcium pectinate matrix tablet loaded with MLX microsponges was developed as a promising system for the colon-specific delivery that has potential for use as an adjuvant therapy for colorectal cancer.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Colon/metabolismo , Tiazinas/administración & dosificación , Tiazoles/administración & dosificación , Algoritmos , Animales , Antiinflamatorios no Esteroideos/farmacocinética , Tampones (Química) , Química Farmacéutica , Difusión , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Emulsiones , Excipientes , Fluoroscopía , Meloxicam , Tamaño de la Partícula , Pectinas , Conejos , Reproducibilidad de los Resultados , Reología , Solubilidad , Solventes , Propiedades de Superficie , Comprimidos , Tiazinas/farmacocinética , Tiazoles/farmacocinética
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