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1.
Ann R Coll Surg Engl ; 105(3): 247-251, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35175143

RESUMEN

INTRODUCTION: Reconstruction of a surgical defect is an important part of the management of oral cancers. Microvascular free flap construction provides better functional and cosmetic outcomes. METHODS: Between 2014 and 2020, some 524 patients underwent microvascular reconstruction. Comorbidity variables were scored using the Charlson Comorbidity Index (CCI). Complications were recorded using Clavien-Dindo criteria. RESULTS: Eighty-three (15.84%), 339 (64.69%) and 102 (19.47%) patients underwent free radial forearm flap, free anterolateral thigh flap and free fibula osteocutaneous flap (FFOCF), respectively. Clavien-Dindo complications of grade III and above were seen in 39 (7.44%) patients. Total flap loss was seen in 18 patients and of these, 16 were salvaged using alternative free flaps or pedicled flaps. On univariate analysis, overall and major complication rates were higher in FFOCF (p=0.171). Major complications significantly more common in patients with a CCI score >4 (p=0.001). Patients aged >65 years had higher rates of complications (p=0.03). CONCLUSION: Microvascular free tissue transfer is a reliable, safe and gold standard modality in surgical reconstruction and can be replicated in non-institutional settings.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de la Boca , Humanos , Neoplasias de la Boca/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Muslo/cirugía , Extremidad Inferior
2.
Food Chem ; 396: 133737, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-35870241

RESUMEN

The drastic increase in the utilization and conversion of biomass has been an effect of sustainability and circular economy in the food processing sector. Rice bran wax (RBW), an intermediate by-product of rice bran oil refining industries, has been one of the underutilized waste materials. The FT-IR analysis showed that RBW contains many similar compounds to that of beeswax (BW) and carnauba wax (CW). The DSC thermographs showed melting and crystallization temperatures of RBW as 78.55 and 73.43 °C, respectively, lesser than CW and more than BW. The peak profiling of XRD diffractographs has shown full-width at half-maximum of CW and RBW as 0.61 and 0.45, respectively, indicating distortion in crystal formation. The sequential extracts of RBW in hexane, dichloromethane, and ethylacetate have shown antimicrobial activity against E. coli and S. typhi. The research provides a baseline for extraction and separation of specialty compounds from RBW for by-product utilization.


Asunto(s)
Escherichia coli , Oryza , Oryza/química , Fitoquímicos , Aceite de Salvado de Arroz/química , Espectroscopía Infrarroja por Transformada de Fourier
3.
Clin Transl Oncol ; 22(1): 37-49, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31006835

RESUMEN

PURPOSE: Breast cancer is a leading cause of cancer mortality in developed countries. We performed a meta-analysis of randomized clinical trials to investigate the effect of metformin on biomarkers associated with breast cancer outcomes and to explore the dose-response relationship. METHODS: A systematic search was performed from onset of the database to January 2019 in MEDLINE/PubMed, SCOPUS, and Cochrane library to identify randomized clinical trials investigating the impact of metformin on insulin, glucose, CRP, leptin, body mass indices (BMI), cholesterol, Ki-67, and Homeostatic Model Assessment for Insulin-Resistance (HOMA-IR). Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI) using a random-effects models. RESULTS: Nine studies providing 1,363 participants were included in the meta-analysis. Pooled results showed a significant reduction in insulin (WMD: - 0.99 U/ml, 95% CI - 1.66, - 0.33), glucose (WMD: - 1.78 ml/dl, 95% CI - 2.96, - 0.60), CRP (WMD: - 0.60 mg/l, 95% CI - 0.88, - 0.33), HOMA-IR (WMD: - 0.45, 95% CI - 0.77, - 0.11), leptin (WMD: - 2.44 ng/ml, 95% CI - 3.28, - 1.61), BMI (WMD: - 0.55 kg/m2, 95% CI - 1.00, - 0.11), and Ki-67 (WMD: - 4.06, 95% CI - 7.59, - 0.54). Results of the subgroup analyses showed that insulin, glucose, and BMI decreased more significantly when the duration of administering metformin intervention was above 4 weeks. We did not observe non-linear changes in the dose-response relationship between metformin and biomarkers as outcomes. CONCLUSIONS: Breast cancer patients receiving metformin as treatment for diabetes showed significant reduction in levels of insulin, fasting glucose, CRP, HOMA, leptin, BMI, and Ki-67.


Asunto(s)
Biomarcadores/sangre , Neoplasias de la Mama/sangre , Neoplasias de la Mama/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Metformina/uso terapéutico , Neoplasias de la Mama/patología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Resistencia a la Insulina , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
Ann Indian Acad Neurol ; 21(3): 209-213, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30258264

RESUMEN

AIM: Limited data regarding stroke subtypes exist from South Asian countries. The aim of the study was to determine the pattern of ischemic stroke subtypes and their associated risk factors, in a 10-year long hospital-based registry in the South Indian city of Hyderabad. MATERIALS AND METHODS: The Hyderabad stroke registry systematically collected clinical, radiological, and laboratory data of fully investigated consecutive stroke patients and studied pattern of ischemic stroke subtypes and their risk factor association. RESULTS: The cohort comprised of 2642 patients: 2072 (78.4%) were ischemic and 570 (21.6%) were hemorrhagic strokes. In the ischemic stroke cohort, the mean age was 54.1 years and 1622 (78.3%) were men. The most common ischemic stroke subtype was large artery atherosclerosis (LAA) comprising 37.6% (n = 779), followed by small vessel occlusion comprising 19.9% (n = 413) and cardioembolism 11% (n = 228). Stroke of other determined etiologies constituted 4.2% (n = 86) and stroke of undetermined etiology was observed in 27.3%. Among patients with LAA, 610 (78.3%) patients had intracranial and 169 (21.7%) had extracranial disease as the underlying mechanism. Risk factor profile demonstrated that hyperlipidemia was significantly associated with LAA and ischemic heart disease with cardioembolic strokes. CONCLUSIONS: The study reveals a distinct pattern of ischemic stroke subtypes in the Indian context that has overlapping features of registries from West and East Asian countries. Both large artery and small vessel diseases are substantially represented with a predominance of intracranial atherosclerosis. The study results have significant implications for developing preventive and management strategies for stroke care and research in India.

5.
Int J Yoga ; 11(1): 53-58, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29343931

RESUMEN

CONTEXT: Different types of breathing exercises have varied effects on cardiovascular parameters and the stress levels in an individual. AIM: The aim of this study was to assess the effect of a modified form of isolated alternate nostril, slow breathing exercise on perceived stress, and cardiovascular parameters in young, male volunteers. SETTINGS AND DESIGN: This was a randomized control study carried out at Advanced Centre for Yoga Therapy Education and Research, Department of Physiology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry in 2014. SUBJECTS AND METHODS: Hundred healthy male volunteers were randomized into control group, n = 50 and slow breathing group (study), n = 50. Slow breathing exercise training was given to study group for 30 min a day, 5 times/week for 12 weeks, under the supervision of certified yoga trainers. Perceived Stress Scale (PSS) using Cohen's questionnaire, anthropometric parameters such as body mass index (BMI), waist-hip ratio (WHR), and cardiovascular parameters such as heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were recorded at baseline and after 12 weeks. The control group did not receive any intervention. Slow breathing exercise training was provided for the study group. During the study period, one volunteer opted out of the study group due to personal reasons. RESULTS: HR, SBP, DBP, and PSS decreased significantly (P < 0.05) in the study group following 12 weeks slow breathing exercise training, while no significant change (P > 0.05) was observed in BMI and WHR. There was no significant change in the control group. CONCLUSION: Twelve weeks of modified slow breathing exercise reduced perceived stress and improved the cardiovascular parameters. The above results indicate that our modified slow breathing exercise is effective in reducing stress and improving the cardiovascular parameters.

6.
Neurol India ; 65(5): 1001-1005, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28879885

RESUMEN

BACKGROUND: Guillain-Barré syndrome (GBS) and its subtypes are associated with distinct anti-ganglioside antibodies. Hence, we aimed to determine the frequency of anti-ganglioside antibodies and its correlation with clinical features, electrophysiological patterns, and outcome in patients with GBS. MATERIAL AND METHODS: The data regarding clinical features, electrophysiological patterns, and outcome at 6 months were collected and analyzed from the case records of patients diagnosed with GBS during 2008-2013 at a tertiary care hospital in south India. RESULTS: A total of 204 patients with GBS were studied, and 73 patients (mean age: 37.6 ± 17.5 years) who underwent anti-ganglioside antibody testing were analyzed. Male-to-female ratio was 2.5:1. IgG anti-ganglioside antibodies were positive in 41/73 patients. The most common IgG anti-ganglioside antibody observed in the acute demyelinating variant was anti-GT1b (n = 13; 17.8%), and, those in the acute axonal variant were anti-GM1, anti-GM2, anti-GD1b, and anti-GT1b antibodies (n = 9;12.3% each). Three patients died and 5 patients were unable to walk independently at the end of 6 months. CONCLUSIONS: The frequency of anti-ganglioside antibodies in our cohort with GBS was 56%, with IgG anti-GT1b antibody being the most common. The anti-ganglioside antibodies were significantly positive in acute motor axonal neuropathy (AMAN) subtype of GBS. The presence of anti-ganglioside antibodies was not found to be of significant use in predicting the outcome. Although it was observed that the absence, and not the presence, of anti-ganglioside antibodies was associated with antecedent infection, dysautonomia, and requirement of ventilator support, the overall disease severity was not antibody dependant.


Asunto(s)
Autoanticuerpos/inmunología , Autoantígenos/inmunología , Gangliósidos/inmunología , Síndrome de Guillain-Barré/inmunología , Síndrome de Guillain-Barré/fisiopatología , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
7.
Biomed Pharmacother ; 91: 436-445, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28475922

RESUMEN

Breast cancer is one of the most frequently diagnosed cancer in woman. Triple-negative breast cancer (TNBC) is most aggressive form of breast cancer. There is a growing interest in the use of natural products in combinational chemotherapy to improve the effectiveness in combating proliferation of cancer cells. Here, we hypothesized that coralyne in combination with paclitaxel may exhibit synergistic effect on inhibition of proliferation, migration and induction of apoptosis in MCF-7 and MDA-MB-231 breast cancer cell lines. MTT and BrdU incorporation assays were performed to study the effect of drugs alone and in combination on cell cytotoxicity and proliferation of the breast cancer cell lines, respectively. Adhesion and wound healing assays were performed to study the cell and extracellular matrix interactions. In addition, expression of proliferation marker ki-67 and apoptotic markers Bax and Bcl-2 was determined to study the effect of coralyne in combination with paclitaxel by reverse transcriptase PCR and confirmed by Western blot. The results indicated the synergism between coralyne and paclitaxel on proliferation and migration of breast cancer cell lines. This study also showed that combinational drug treatment decreased the expression of ki-67 and there was an increase in pro apoptotic factor Bax with decreased in expression of anti-apoptotic factor Bcl-2 in breast cancer cell lines with negligible effect on normal breast cell line. Overall, our data described the promising therapeutic potential of coralyne in combination with paclitaxel in treating breast cancer at lower effective dose.


Asunto(s)
Alcaloides de Berberina/farmacología , Neoplasias de la Mama/patología , Movimiento Celular/efectos de los fármacos , Paclitaxel/farmacología , Alcaloides de Berberina/química , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Interacciones Farmacológicas , Sinergismo Farmacológico , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Células MCF-7 , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Paclitaxel/química , ARN Mensajero/genética , ARN Mensajero/metabolismo
8.
Indian J Med Res ; 143(6): 793-797, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27748304

RESUMEN

BACKGROUND & OBJECTIVES: Ingestion of Cleistanthus collinus causes hypokalemia and cardiac arrhythmias leading to mortality in most cases. We undertook this retrospective study to evaluate the clinical presentation and predictors of outcome in critically ill patients admitted with C. collinus poisoning. METHODS: The case records of 56 patients admitted to the medical intensive care unit (MICU) of a tertiary care teaching hospital in south India (2000-2014) with C. collinus poisoning were retrospectively analysed. RESULTS: The mean age of patients was 36.7±13.3 yr; there were 30 males. Salient clinical manifestations included hypokalemia (58%), neutrophilic leucocytosis (48.2%), acute kidney injury (AKI) (42.9%), acute respiratory failure requiring mechanical ventilation (AcRFMv) (32.1%), shock (21.4%); cardiac arrhythmias and neuromuscular weakness (19.6% each); 21 patients (37.5%) had adverse outcome. Longer time-lapsed from consumption to reaching emergency room [median (interquartile range)] (hours) [49 (22-97) vs. 28 (7-56), p =0.0380 ]; higher acute physiology and chronic health evaluation II (APACHE II) score at presentation [14 (8.25-14.75) vs. 2 (0-6) P<0.001]; and presence of the following [odds ratio (95% confidence intervals)] at initial presentation: shock [37.40 (4.29-325.98), P=0.001]; AcRFMv [26.67 (5.86-121.39), P<0.001]; elevated alanine aminotransferase [5.71 (1.30-25.03), p0 =0.021]; metabolic acidosis [5.48 (1.68-17.89), P=0.005]; acute kidney injury (AKI) [5 (1.55-16.06), P=0.007]; hyponatremia [4.67 (1.25-17.44), P=0.022]; and neutrophilic leucocytosis [3.80 (1.02-14.21), P=0.047] predicted death. A significant (P<0.001) increasing trend in mortality was observed with increasing International Program on Chemical Safety Poisoning Severity Score (IPCS-CSS) grade. INTERPRETATION & CONCLUSIONS: C. collinus is a lethal poison associated with high mortality for which there is no specific antidote. Careful search and meticulous monitoring of the predictors of death and initiating appropriate corrective measures can be life saving.


Asunto(s)
Lesión Renal Aguda/fisiopatología , Arritmias Cardíacas/fisiopatología , Euphorbiaceae/toxicidad , Hipopotasemia/fisiopatología , Intoxicación por Plantas/fisiopatología , Adolescente , Adulto , Anciano , Femenino , Humanos , India , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Centros de Atención Terciaria
9.
Int Sch Res Notices ; 2016: 9458627, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28116350

RESUMEN

Embedded systems are extensively used in home automation systems, small office systems, vehicle communication systems, and health service systems. The services provided by these systems are available on the Internet and these services need to be protected. Security features like IP filtering, UDP protection, or TCP protection need to be implemented depending on the specific application used by the device. Every device on the Internet must have network interface. This paper proposes the design of the embedded Secured Ethernet Interface System to protect the service available on the Internet against the SYN flood attack. In this experimental study, Secured Ethernet Interface System is customized to protect the web service against the SYN flood attack. Secured Ethernet Interface System is implemented on ALTERA Stratix IV FPGA as a system on chip and uses the modified SYN flood attack protection method. The experimental results using Secured Ethernet Interface System indicate increase in number of genuine clients getting service from the server, considerable improvement in the data transfer rate, and better response time during the SYN flood attack.

10.
Opt Express ; 22(10): 12238-47, 2014 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-24921342

RESUMEN

An insulator-metal-insulator plasmonic interconnect using TiN, a CMOS-compatible material, is proposed and investigated experimentally at the telecommunication wavelength of 1.55 µm. The TiN waveguide was shown to obtain propagation losses less than 0.8 dB/mm with a mode size of 9.8 µm on sapphire, which agree well with theoretical predictions. A theoretical analysis of a solid-state structure using Si(3)N(4) superstrates and ultra-thin metal strips shows that propagation losses less than 0.3 dB/mm with a mode size of 9 µm are attainable. This work illustrates the potential of TiN as a realistic plasmonic material for practical solid-state, integrated nano-optic and hybrid photonic devices.

11.
Int J Plant Genomics ; 2014: 651912, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24895494

RESUMEN

Pigeonpea (Cajanus cajan (L) Millsp.) is an important food legume crop of rain fed agriculture in the arid and semiarid tropics of the world. It has deep and extensive root system which serves a number of important physiological and metabolic functions in plant development and growth. In order to identify genes associated with pigeonpea root, ESTs were generated from the root tissues of pigeonpea (GRG-295 genotype) by normalized cDNA library. A total of 105 high quality ESTs were generated by sequencing of 250 random clones which resulted in 72 unigenes comprising 25 contigs and 47 singlets. The ESTs were assigned to 9 functional categories on the basis of their putative function. In order to validate the possible expression of transcripts, four genes, namely, S-adenosylmethionine synthetase, phosphoglycerate kinase, serine carboxypeptidase, and methionine aminopeptidase, were further analyzed by reverse transcriptase PCR. The possible role of the identified transcripts and their functions associated with root will also be a valuable resource for the functional genomics study in legume crop.

12.
Artículo en Inglés | MEDLINE | ID: mdl-25570345

RESUMEN

Autism Spectrum Disorder (ASD) is a neural development disorder affecting the information processing capability of the brain by altering how nerve cells and their synapses interconnect and organize. Electroencephalograph or EEG signals records the electrical activity of the brain from the scalp which can be utilized to identify and investigate the brain wave pattern which are specific to individuals with ASD. Therefore, the analysis of ASD can be done by scrutinizing the specific bands (Theta, Mu and Beta) of the EEG signal. However, EEG signals are mainly contaminated by Ocular (Eye-blink) and Myogenic artefacts which pose problems in EEG interpretation. In this paper an automated real-time method for detection and removal of Ocular and Myogenic artefacts for multichannel EEG signal is proposed which would enhance the diagnostic accuracy. The proposed methodology has been validated against 20 subjects from Caltech, Physionet, Swartz Center for Computational Neuroscience and the computed average correlation and regression are 0.7574 and 0.6992 respectively.


Asunto(s)
Artefactos , Trastorno del Espectro Autista/fisiopatología , Parpadeo/fisiología , Electroencefalografía/métodos , Músculos/fisiopatología , Procesamiento de Señales Asistido por Computador , Automatización , Humanos , Masculino , Factores de Tiempo
13.
Biotechnol Rep (Amst) ; 4: 56-59, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28435801

RESUMEN

Due to lack of morphological methods to identify sex at early stage in the plants with long juvenile period the application of molecular markers is expected to facilitate breeding program. The objective of this study is to identify molecular markers linked to sex determination of the plant Simarouba glauca which assists in crop improvement program. Random amplified polymorphic DNA primers were tested on dioeceious and hermaphrodite plant Simarouba glauca. A set of eighty five RAPD primers were screened out of which only five primers were found to be associated with sex. The primer OPU-10 is male specific and OPD-19 primer is female specific. Another primer OPU-19 produced a unique amplification in only hermaphrodite individuals. Female and hermaphrodite specific primer OPS-05 amplified an amplicon in female and hermaphrodite and was absent in male plant. Primer OPW-03 produced amplicon specific to male and hermaphrodite plants and was absent in female plants.

15.
Opt Express ; 20(7): 8100-16, 2012 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-22453481

RESUMEN

We directly demonstrate an improvement in the radiative decay rate of dye molecules near multilayer hyperbolic metamaterials (HMMs). Our comprehensive study shows a radiative decay rate for rhodamine 800 (Rh800) that is several times higher due to the use of HMM samples as compared to dielectric substrates. This is also the first experimental demonstration that multilayer hyperbolic metamaterials provide an increase in the radiative decay rate relative to those from either thin or thick gold films.


Asunto(s)
Colorantes/química , Materiales Manufacturados , Semivida , Cinética
16.
J Ind Microbiol Biotechnol ; 39(1): 93-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21691794

RESUMEN

The thermoalkalophilic Bacillus halodurans JB 99 cells known for production of novel thermostable alkaline keratinolytic protease were immobilized in calcium alginate matrix. Batch and repeated batch cultivation using calcium alginate immobilized cells were studied for alkaline protease production in submerged fermentation. Immobilized cells with 2.5% alginate and 350 beads/flask of initial cell loading showed enhanced production of alkaline protease by 23.2% (5,275 ± 39.4 U/ml) as compared to free cells (4,280 ± 35.4 U/ml) after 24 h. In the semicontinuous mode of cultivation, immobilized cells under optimized conditions produced an appreciable level of alkaline protease in up to nine cycles and reached a maximal value of 5,975 U/ml after the seventh cycle. The enzyme produced from immobilized cells efficiently degraded chicken feathers in the presence of a reducing agent which can help the poultry industry in the management of keratin-rich waste and obtaining value-added products.


Asunto(s)
Alginatos , Bacillus/enzimología , Proteínas Bacterianas/biosíntesis , Endopeptidasas/biosíntesis , Animales , Proteínas Bacterianas/metabolismo , Células Inmovilizadas/enzimología , Endopeptidasas/metabolismo , Estabilidad de Enzimas , Plumas/metabolismo , Fermentación , Ácido Glucurónico , Ácidos Hexurónicos , Temperatura
17.
Rev Sci Instrum ; 81(11): 116103, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21133505

RESUMEN

Multivariate system spectroscopic model plays important role in understanding chemometrics of ensemble under study. Here in this manuscript we discuss various approaches of modeling of spectroscopic system and demonstrate how Lorentz oscillator can be used to model any general spectroscopic system. Chemometric studies require customized templates design for the corresponding variants participating in ensemble, which generates the characteristic matrix of the ensemble under study. The typical biological system that resembles human blood tissue consisting of five major constituents i.e., alanine, urea, lactate, glucose, ascorbate; has been tested on the model. The model was validated using three approaches, namely, root mean square error (RMSE) analysis in the range of ±5% confidence interval, clerk gird error plot, and RMSE versus percent noise level study. Also the model was tested across various template sizes (consisting of samples ranging from 10 up to 1000) to ascertain the validity of partial least squares regression. The model has potential in understanding the chemometrics of proteomics pathways.


Asunto(s)
Modelos Estadísticos , Análisis Espectral/métodos , Humanos , Análisis de los Mínimos Cuadrados , Análisis Multivariante
18.
Artículo en Inglés | MEDLINE | ID: mdl-21097298

RESUMEN

Classification of surface electromyogram (sEMG) signal is important for various applications such as prosthetic control and human computer interface. Surface EMG provides a better insight into the strength of muscle contraction which can be used as control signal for different applications. Due to the various interference between different muscle activities, it is difficult to identify movements using sEMG during low-level flexions. A new set of fractal features - fractal dimension and Maximum fractal length of sEMG has been previously reported by the authors. These features measure the complexity and strength of the muscle contraction during the low-level finger flexions. In order to classify and identify the low-level finger flexions using these features based on the fractal properties, a recently developed machine learning based classifier, Twin Support vector machines (TSVM) has been proposed. TSVM works on basic learning methodology and solves the classification tasks as two SVMs for each classes. This paper reports the novel method on the machine learning based classification of fractal features of sEMG using the Twin Support vector machines. The training and testing was performed using two different kernel functions - Linear and Radial Basis Function (RBF).


Asunto(s)
Inteligencia Artificial , Diagnóstico por Computador/métodos , Electromiografía/métodos , Fractales , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Reconocimiento de Normas Patrones Automatizadas/métodos , Algoritmos , Femenino , Antebrazo/fisiología , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Electromyogr Clin Neurophysiol ; 48(3-4): 169-80, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18551837

RESUMEN

Surface electromyogram (sEMG) has numerous applications. It has been widely used in various biosignal and neuro rehabilitation applications. There is an urgent need for establishing a simple yet robust system that can be used to identify subtle complex hand actions and gestures for control of prosthesis and other computer assisted devices. Earlier work to identify the hand actions and gestures based on sEMG suffers from limitation that these are suitable for gross actions where there is only one prime-mover muscle involved and not suitable for small subtle and complex muscle contraction. This paper presents the hand gesture identification using sEMG decomposed using semi-blind independent component analysis combined with neural network based classifier. The aim was to provide reliable and natural control for rehabilitation and human computer interaction applications. We have proposed a model based approach where the hand muscle anatomy is known. The system was tested on 5 subjects and with experiments repeated on different days. The system was compared with raw sEMG as used by other researchers. The system is able to classify the different hand actions 100%. In comparison, the classification of the traditional ICA and raw sEMG for the same experiments and similar features was a poor 65% and 60% respectively. This research demonstrates that sEMG can be decomposed to the individual muscle activities using semi-blind ICA. The muscle activity after decomposition can be used to accurately identify small and subtle hand actions and gestures. Finally the ICA source separation was validated with mixing matrix analysis.


Asunto(s)
Inteligencia Artificial , Miembros Artificiales , Electromiografía/estadística & datos numéricos , Gestos , Mano/inervación , Redes Neurales de la Computación , Reconocimiento de Normas Patrones Automatizadas , Procesamiento de Señales Asistido por Computador , Interfaz Usuario-Computador , Potenciales de Acción/fisiología , Adulto , Femenino , Mano/fisiología , Humanos , Contracción Isométrica/fisiología , Masculino , Neuronas Motoras/fisiología , Músculo Esquelético/inervación , Análisis de Componente Principal
20.
Curr Med Res Opin ; 24(6): 1771-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18479589

RESUMEN

OBJECTIVE: To compare the efficacy and safety of low-dose chlorthalidone + atenolol combination with atenolol and atenolol + amlodipine combination in stage I hypertensive patients uncontrolled on active run-in monotherapy. METHODS: Newly diagnosed stage I hypertensive patients were randomized to active run-in monotherapy either with atenolol 25 mg (98/300) or chlorthalidone 6.25 mg (100/300) or amlodipine 2.5 mg (102/300). A total of 282/300 patients (atenolol 92, chlorthalidone 91, amlodipine 99) completed the active run-in phase successfully. Patients uncontrolled on active run-in monotherapy (atenolol 33, chlorthalidone 45, amlodipine 47) received the study treatment, namely atenolol 50 mg alone, chlorthalidone 6.25 mg+atenolol 25 mg and atenolol 25 mg+amlodipine 2.5 mg, respectively. Efficacy of the therapy was evaluated by BP measurement at weeks 12 and 20 post-therapy. RESULTS: Post-active run-in monotherapies, the study treatment groups showed a significant fall in mean SBP and DBP from baseline (p<0.05). The mean fall in SBP and DBP was comparable for study treatments (atenolol 50 mg, atenolol 25 mg+chlorthalidone 6.25 mg and atenolol 25 mg+amlodipine 2.5 mg) (p=0.337 for SBP and p=0.054 for DBP) at week 12 and (p=0.744 for SBP and p=0.855 for DBP) at week 20; also, the percentage of responders was comparable for the three study treatment groups (p=0.799) indicating that the low-dose chlorthalidone+atenolol combination is noninferior to the high-dose atenolol alone and atenolol+amlodipine combination. No serious laboratory/clinical adverse events were reported in this study. CONCLUSION: Chlorthalidone 6.25 mg in combination with atenolol 25 mg is effective and safe in stage I (JNC 7) essential hypertensive patients. This low dose of chlorthalidone could reduce dose-related concerns over metabolic adverse effects and may lead to wider usage of this proven antihypertensive agent in combination therapy.


Asunto(s)
Antihipertensivos/administración & dosificación , Antihipertensivos/farmacología , Atenolol/administración & dosificación , Atenolol/farmacología , Clortalidona/administración & dosificación , Clortalidona/farmacología , Hipertensión/tratamiento farmacológico , Adulto , Antihipertensivos/uso terapéutico , Atenolol/uso terapéutico , Clortalidona/uso terapéutico , Quimioterapia Combinada , Femenino , Humanos , Hipertensión/clasificación , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
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