Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Front Behav Neurosci ; 18: 1433431, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993266

RESUMO

Investigations in Wistar Albino Glaxo from Rijswijk (WAG/Rij) rats that are susceptible to genetic absence epilepsy have demonstrated that environmental modifications affect absence seizures. Previously, we showed that neonatal tactile stimulations produce disease-modifying effect on genetically determined absence epilepsy and associated depression in Wag/Rij rats. The study presented here examined the effect of TS during late ontogenesis (adolescence and young adulthood) on epilepsy and depression outcomes in this genetically epileptic rat strain. On postnatal day (PND) 38, male WAG/Rij rats randomly were assigned to either the tactile stimulation (TS), handled or control group (unhandled) with 8 animals in each group. Following a 7-day adaptation period to their new surroundings, the animals were submitted to tactile stimulation from PND 45 to PND 90, five days per week, for 5 min daily. The tactile-stimulated rat was removed from its cage, placed on the experimenter's lap, and had its neck and back gently stroked by the researcher. The handled rats were taken to another cage and left alone for 5 min daily from PND 45 to PND 90. The control rats were left undisturbed in their home cage, except for regular cage cleaning. After PND 90, all rats were left undisturbed until behavioral testing and EEG recording. When the animals were 7 months old, they were subjected to the sucrose consumption test (SCT) and the forced swimming test (FST). Electroencephalogram (EEG) recordings were made at 8 months of age in order to measure electroencephalographic seizure activity, thus, the spike-wave discharges (SWDs). Tactile-stimulated rats showed increased sucrose consumption and number of approaches to the sucrose solution in the SCT when compared with the handled and control rats. In the FST, rats in TS group showed lower immobility time and greater immobility latency, active swimming time and diving frequency than the handled and control rats. The duration and the number of seizures were not different amongst the groups. The data obtained suggest that TS in young rats is able to prevent depression in WAG/Rij rats.

2.
Clin Med Insights Case Rep ; 16: 11795476221148866, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36760339

RESUMO

The Rubinstein-Taybi Syndrome (RSTS) literature is limited about sensory integration, which is a foundational neurological function of the central nervous system that may affect the development of cognitive, social, and motor skills. The aim of this case report was to investigate the effects of Ayres Sensory Integration® (ASI) intervention on processing and integrating sensations, motor functions and parental goals of 3-year-old child with RSTS. Analysis of assessment data reviewed before and after treatment. Assessment collected by interview, Sensory Profile (SP), Sensory Processing Measure-Preschool (SPM-P) Home, Peabody Developmental Motor Scales-2 (PDMS-2), Gross Motor Function Measurement-88 (GMFM-88), and Gross Motor Function Classification System (GMFCS). Progress toward goals and objectives was measured with Goal Attainment Scale (GAS). ASI intervention was implemented 3 times per week for 8 weeks. At pre-intervention, SP and SPM-P Home revealed prominent sensory processing and integration difficulties in this case. PDMS-2 scores indicated the child was far behind his peers in fine and gross motor areas. In addition, systematic observations determined that the child's GMFCS level was III. After 8 weeks of ASI intervention significant improvements were found in parent reports of sensory processing in the areas of vestibular, tactile, and oral functioning on the Sensory Profile. Gains in functional motor skills were found on the GMFM-88 and the GMFCS. Consistent with these results, significant gains at or above expected levels of performance were found on GAS goals which reflected the family's main concerns for social participation, feeding, play, and movement. There are limited studies on sensory processing and integration in children with RSTS. This case report identified sensory processing and integration difficulties for the first time in a child with RSTS. Results also provide preliminary support for the positive effects of ASI intervention on sensory processing, functional motor skills, and parental goals of a child with RSTS.

3.
J Plast Surg Hand Surg ; 57(1-6): 445-452, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36476277

RESUMO

BACKGROUND: In patients with nerve tissue defects, the use of autologous nerve grafts is the standard method of treatment. Alternatives to autologous, nerve grafts have attracted the attention of reconstructive surgeons. In this study, the results of nerve repairs using acellular dermal matrix (ADM) in an experimental rat sciatic nerve defect model are presented. METHODS: Thirty-six Sprague-Dawley rats were randomized into 5 groups: Group 1: control group, Group 2: negative control group (n = 6), Group 3: autologous nerve graft group (n = 10), Group 4: donor site entubulated with ADM group (n = 10); and Group 5: nerve graft entubulated with ADM group (n = 10). The animals in each group were evaluated for electrophysiologic functions, gastrocnemius muscle weight and histomorphology on the 3rd and 6th month. RESULTS: The compound muscle action potential was observed to be distinctly lower in Groups 3, 4 and 5 in comparison to the control group. In Group 4, the gastrocnemius ratio (GCR) values on the 6th month were statistically significantly lower than the GCR values in Group 3 and Group 5, The histological scores and myelinated axonal counts in Group 5 were statistically significantly higher than the values in Group 3 and Group 4. CONCLUSION: The results of this study showed that wrapping ADM around nerve grafts resulted in better outcomes with respect to nerve healing.


Assuntos
Derme Acelular , Procedimentos de Cirurgia Plástica , Ratos , Animais , Ratos Sprague-Dawley , Nervo Isquiático/cirurgia , Nervo Isquiático/fisiologia , Cicatrização
4.
Neurol India ; 70(Supplement): S259-S262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36412378

RESUMO

Background: Current methods used to measure the muscle strength required to achieve plantar flexion may yield highly variable results depending on the perception of the physician conducting the examination because these tests involve subjective and qualitative evaluation. Objective: To describe and evaluate the efficacy of a novel examination technique that can quantitatively measure plantar flexion in L5-S1 disc herniation. Materials and Methods: A total of 32 patients (average age: 49.4 years, range: 23-78) with L5-S1 disc herniations were included. The patient to be tested stood next to a table on which they could lean with their hands. The leg closer to the table was fully flexed at the knee, and the other foot was brought to maximum plantar flexion on the toes. At this point, a stopwatch was started to measure the time that passed until the muscles fatigued and the heel fell. The differences between the right and left plantar flexion times were noted. In addition, three different physicians graded muscle strength by using the classical "The Medical Research Council of the United Kingdom" method. Results: The time until fatigue in right and left plantar flexion was measured using the proposed method, and each test underwent a video recording. The Yilmaz-Ilbay plantar flexion test yielded the correct classification for all cases. Conclusion: We suggest that the proposed method "Yilmaz-Ilbay plantar flexion test" can serve as a useful, practical, and effective test to detect quantitative evaluation of plantar flexion in L5-S1 herniation.


Assuntos
Deslocamento do Disco Intervertebral , Vértebras Lombares , Exame Neurológico , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/diagnóstico , Extremidade Inferior , Força Muscular , Exame Neurológico/métodos , Exame Neurológico/normas , Amplitude de Movimento Articular
5.
Neural Plast ; 2022: 7251460, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465396

RESUMO

Objective: The aim of our study is to examine the effects of neonatal tactile stimulations on the brain structures that previously defined as the focus of epilepsy in the Wistar-Albino-Glaxo from Rijswijk (WAG/Rij) rat brain with genetic absence epilepsy. Methods: In the present research, morphology and density of dendritic spines were analyzed in layer V pyramidal neurons of the somatosensory cortex (SoCx) of WAG/Rij rats (nonstimulated control, tactile-stimulated, and maternal separated rats) and healthy Wistar (nonepileptic) rats. To achieve this, a Golgi-Cox method was used. Results: Dendritic spine number in layer V of the SoCx has been detected significantly higher in adult WAG/Rij rats at postnatal day 150 in comparison to nonepileptic adult control Wistar rats (p < 0.001). Moreover, quantitative analyses of dendrite structure in adult WAG/Rij rats showed a decrease in dendrite spine density of pyramidal neurons of SoCx which occurred in early neonatal exposure to maternal separation (MS) and tactile stimulation (TS) (p < 0.001). Conclusions: Our findings provide the first evidence that tactile stimulations during the early postnatal period have a long-term impact on dendrite structure in WAG/Rij rat's brain and demonstrate that neonatal tactile stimulation can regulate dendritic spines in layer V in pyramidal neurons of SoCx in epileptic brains.


Assuntos
Espinhas Dendríticas , Córtex Somatossensorial , Animais , Modelos Animais de Doenças , Eletroencefalografia , Privação Materna , Células Piramidais , Ratos , Ratos Wistar
6.
Brain Sci ; 12(3)2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35326317

RESUMO

The present study aims to investigate effect of early caffeine exposure on epileptogenesis and occurrence of absence seizures and comorbid depression in adulthood. For this purpose, Wistar Albino Glaxo from Rijswijk (WAG/Rij) rats were enrolled in a control and two experimental groups on the 7th day after the delivery. The rats in experimental groups received either 10 or 20 mg/kg caffeine subcutaneously while animals in control group had subcutaneous injections of 0.9% saline. The injections started at postnatal day 7 (PND7) and were continued each day for 5 days. At 6-7 months of age, electroencephalogram (EEG) recordings and behavioral recordings in the forced swimming test, sucrose consumption/preference test and locomotor activity test were carried out. At 6 months of age, 10 mg/kg and 20 mg/kg caffeine-treated WAG/Rij rats showed increased immobility latency and active swimming duration in forced swimming test when compared with the untreated controls. In addition, 20 mg/kg caffeine treatment decreased immobility time. In sucrose preference/consumption tests, WAG/Rij rats in 10 mg/kg caffeine group demonstrated higher sucrose consumption and preference compared to untreated controls. The rats treated with 20 mg/kg caffeine showed higher sucrose preference compared to control rats. The exploratory activity of rats in the 10 mg/kg caffeine-treated group was found to be higher than in the 20 mg/kg caffeine-treated and control groups in the locomotor activity test. At 7 months of age, caffeine-treated animals showed a decreased spike-wave discharge (SWD) number compared to the control animals. These results indicate that postnatal caffeine treatment may decrease the number of seizure and depression-like behaviors in WAG/Rij rats in later life. Caffeine blockade of adenosine receptors during the early developmental period may have beneficial effects in reducing seizure frequency and depression-like behaviors in WAG/Rij rat model.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 254: 119639, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33743307

RESUMO

Diabetic wounds have a slow healing process and easy to be infected. In addition to current drug treatments, supportive approaches are needed for diabetic wound treatment. In this study, we aimed to load Aloe Vera (AV) and Hypericum perforatum oil (HPO) with PCL/Ge (Poly (ɛ-caprolactone)/Gelatine) polymeric biodegradable by electrospinning method into nanofiber dressings on an experimental diabetic wound model to compare the diabetic wound healing effect. Changes in the amount and chemical structure of phospholipids, proteins, and lipids were investigated in the blood and serum samples of the animals using Fourier transform infrared (FTIR) analysis. To evaluate biological events associated with the wound repair process in inflammatory phase we used oxidant and antioxidant status to determine the healing status of wounds such as Total antioxidant status (TAS), Total oxidant level (TOS) and tumor necrosis factor alpha (TNF-α) levels. TOS level increased in DM groups and decreased in the AV and HPO group. Oxidative stress index decreased and TNF-α level increased in the HPO group. FTIR spectra showed changes in the phospholipids, proteins, and carbon chain of lipids in the whole blood as well as serum of DM rats. FTIR spectra combined with Principal component analysis (PCA) showed, that treated DM rats by AV and HPO caused return chemical structure of blood and serum to this observed in control group. Higher similarity with control group for HPO rats was observed. HPO is better than AV in the alternative for healing on diabetic wound. Thus, we have demonstrated that IR spectroscopy and multivariate data analysis and biochemical assays are consistent and correlative with each other.


Assuntos
Aloe , Diabetes Mellitus , Hypericum , Nanofibras , Animais , Bandagens , Ratos , Cicatrização
8.
Front Behav Neurosci ; 14: 132, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32792925

RESUMO

Recent studies suggest that development of absence epilepsy and comorbid depression might be prevented by increased maternal care of the offspring, in which tactile stimulation induced by licking/grooming and non-nutritive contact seem to be crucial. In this study, we aimed to evaluate the effect of neonatal tactile stimulations (NTS) on absence epilepsy and depression-like behaviors in adulthood. Wistar Albino Glaxo from Rijswijk (WAG/Rij) rat pups with a genetic predisposition to absence epilepsy were divided into tactile stimulation (TS) group, deep touch pressure (DTP) group, maternal separation (MS) group or control group. Between postnatal day 3 and 21, manipulations (TS, DTP, and MS) were carried out for 15 min and three times a day. Animals were submitted to locomotor activity, sucrose consumption test (SCT) and forced swimming test (FST) at five months of age. At the age of six months, the electroencephalogram (EEG) recordings were conducted in order to quantify the spike-wave discharges (SWDs), which is the hallmark of absence epilepsy. The TS and DTP groups showed less and shorter SWDs in later life in comparison to maternally separated and control rats. SWDs' number and total duration were significantly reduced in TS and DTP groups whereas mean duration of SWDs was reduced only in DTP group (p < 0.05). TS and DTP also decreased depression-like behaviors measured by SCT and FST in adult animals. In the SCT, number of approaches was significantly higher in TS and DTP groups than the maternally separated and control rats. In the FST, while the immobility latency of TS and DTP groups was significantly higher, only TS group showed significantly decreased immobility and increased swimming time. The results showed that NTS decreases both the number and length of SWDs and the depression-like behaviors in WAG/Rij rats probably by increasing arousal level and causing alterations in the level of some neurotrophic factors as well as in functions of the neural plasticity in the developing rat's brain.

9.
Appl Spectrosc ; 72(5): 689-705, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28905646

RESUMO

The severe sole effects of seizures on the cortical part of bone were reported in our previous study. However, the side effects of anti-epileptic drug therapy on bones has not been differentiated from the effects of the convulsive seizures, yet. This study provides the first report on differentiation of the effects of seizures and carbamazepine (a widely used antiepileptic drug) therapy on bones; 50 mg/kg/day drug was given to genetically induced absence epileptic rats for five weeks. Distinct bone regions including cortical, trabecular, and growth plate in each of tibia, femur, and spine tissues were studied using Fourier transform infrared (FT-IR) imaging and Vickers microhardness test. Blood levels of vitamin D and bone turnover biomarkers were also measured. According to the FT-IR imaging results, both seizure and carbamazepine-treated groups, more dominantly the drug-treated group, had lower mineral content with altered collagen crosslinks and higher crystallinity, implying reduced bone strength. Lower microhardness values also supported lower mechanical strength in bones. The most affected bone tissue and region from seizures and treatment was found as the spine and cortical, respectively. While there was a reduction in vitamin D and calcium levels in both seizure and carbamazepin-treated groups, significantly elevated PTH and bone turnover biomarkers were only seen in the drug-treated group.


Assuntos
Anticonvulsivantes/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas , Osso e Ossos , Carbamazepina/efeitos adversos , Convulsões , Animais , Anticonvulsivantes/uso terapêutico , Doenças Ósseas Metabólicas/induzido quimicamente , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/fisiopatologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiopatologia , Cálcio/sangue , Carbamazepina/uso terapêutico , Modelos Animais de Doenças , Testes de Dureza , Masculino , Ratos , Ratos Transgênicos , Ratos Wistar , Convulsões/complicações , Convulsões/tratamento farmacológico , Espectroscopia de Infravermelho com Transformada de Fourier , Vitamina D/sangue
10.
Turk Neurosurg ; 26(2): 291-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26956828

RESUMO

AIM: Epineural adhesion after peripheral nerve surgery is common. The purpose of this study was to evaluate the macroscopic and histopathologic effects of topical mitomycin C and daunorubicin on epineural scar formation. MATERIAL AND METHODS: In this study, we used 15 rats (30 nerves). Two test groups and one control group were created. Sciatic nerve exposure was created bilaterally in each group (30 nerve examinations in total). In experimental group 1, cotton pads that had absorbed mitomycin C (0.5 mg/ml) were placed onto the nerves for 5 minutes while in experimental group 2, cotton pads that had absorbed daunorubicin (0.2 mg/ml) were placed onto the nerves for 5 minutes and cotton pads that had absorbed saline were applied to the control group. Eight weeks after the first surgery, surgical dissection was performed for the evaluation of neurolysis sites. Epineural adhesions were classified utilizing a numerical grading layout. RESULTS: We did not find any adverse effect with topically applied mitomycin C and daunorubicin. Within the 3 groups, no significant difference was seen in skin and fascia-muscle cavity closure (p > 0.05). Macroscopically, mitomycin C and daunorubicin decreased the adhesion of sciatic nerve to adjacent structures. There was intensive epineural scar formation in the control group. Scar tissue thickness and fibroblast/fibrocyte cell number were less in the two test groups compared with the control group (p < 0.001). There was no statistical difference between the two test groups. CONCLUSION: Epineural scar formation after peripheral nerve surgery may be reduced by using topical application of mitomycin C and daunorubicin.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Daunorrubicina/farmacologia , Mitomicina/farmacologia , Procedimentos Neurocirúrgicos/efeitos adversos , Nervos Periféricos/patologia , Aderências Teciduais/prevenção & controle , Animais , Cicatriz/patologia , Modelos Animais de Doenças , Feminino , Fibrose/prevenção & controle , Ratos , Nervo Isquiático/patologia , Nervo Isquiático/cirurgia , Aderências Teciduais/patologia
11.
Biochim Biophys Acta ; 1838(12): 3088-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25194682

RESUMO

Epilepsy is characterized by disruption of balance between cerebral excitation and inhibition, leading to recurrent and unprovoked convulsions. Studies are still underway to understand mechanisms lying epileptic seizures with the aim of improving treatment strategies. In this context, the research on brain tissue membranes gains importance for generation of epileptic activities. In order to provide additional information for this field, we have investigated the effects of pentylenetetrazol-induced and audiogenetically susceptible epileptic seizures on structure, content and function of rat brain membrane components using Fourier transform infrared (FT-IR) spectroscopy. The findings have shown that both two types of epileptic seizures stimulate the variations in the molecular organization of membrane lipids, which have potential to influence the structures in connection with functions of membrane proteins. Moreover, less fluid lipid structure and a decline in content of lipids obtained from the ratio of CH3 asym/lipid, CH2 asym/lipid, CO/lipid, and olefinicCH/lipid and the areas of the PO2 symmetric and asymmetric modes were observed. Moreover, based on IR data the changes in the conformation of proteins were predicted by neural network (NN) analysis, and displayed as an increase in random coil despite a decrease in beta sheet. Depending on spectral parameters, we have successfully differentiated treated samples from the control by principal component analysis (PCA) and cluster analysis. In summary, FT-IR spectroscopy may offer promising attempt to identify compositional, structural and functional alterations in brain tissue membranes resulting from epileptic activities.

12.
Anal Chem ; 86(3): 1395-403, 2014 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-24377319

RESUMO

To accomplish the appropriate treatment strategies of epilepsy action mechanisms underlying epileptic seizures should be lightened. The identification of epileptic seizure-induced alterations on the brain related to their pathologies may provide information for its action mechanism. Therefore, the current study determined molecular consequences of seizures induced by pentylenetetrazol (PTZ), which is a widely used convulsant agent, on rat brain. The rats were administered subconvulsant (25 mg/kg) and convulsant (60 mg/kg) doses of PTZ during a week, and brain tissues were studied by Fourier transform infrared (FT-IR) spectroscopy. Results revealed a decrease in lipid fluidity and lipid and protein content and also the differences in membrane packing by changing the nature of hydrogen bonding as indicated by the C═O, the PO(-)2 symmetric, and asymmetric bands. Monitoring of the olefinic band elicited seizure-induced lipid peroxidation further confirmed by the thiobarbituric acid (TBAR) assay. Additionally, PTZ-induced convulsions led to alterations in protein structures obtained by neural network (NN) predictions like an increase in random coils. On the basis of the spectral changes, treated samples could be successfully differentiated from the controls by cluster analysis. Consequently, the convulsive dose of PTZ caused more significant molecular variations compared to the subconvulsive one. All findings might have an important role in understanding the molecular mechanisms underlying epileptic activities.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Pentilenotetrazol/efeitos adversos , Convulsões/induzido quimicamente , Convulsões/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Animais , Encéfalo/fisiopatologia , Análise por Conglomerados , Relação Dose-Resposta a Droga , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Convulsões/fisiopatologia
13.
Brain Res Bull ; 83(6): 356-9, 2010 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-20858533

RESUMO

OBJECTIVES: the aim of our study was to evaluate the activity of superoxide dismutase (SOD) and the levels of glutathione (GSH), malondialdehyde (MDA), and nitric oxide (NO) in liver and kidney tissues in a rat model of convulsive seizure induced by single and repeated doses of pentylenetetrazole (PTZ) and sound stimulation with key ringing. MATERIALS AND METHODS: male Wistar adult rats (n=48), were used in the experiment. The animals were divided into six groups: (1) Single Seizure Control Group (SS-Control; n=8), (2) Repeated Seizures Control Group (RS-Control; n=8), (3) PTZ induced Single Seizure Group (SS-PTZ Group; n=8), (4) PTZ induced Repeated Seizures Group (RS- PTZ Group; n=8), (5) Key-Ringing Induced Single Seizure Group (SS-KEY Group; n=8), (6) Key-Ringing Induced Repeated Seizures Group (RS-KEY Group; n=8). Following injections rats were observed for seizure activity for 30 min. Animals were sacrificed 24h after induced seizure (single or last seizure) or saline administration. MDA, NO, GSH levels and SOD activities were determined in liver and kidney tissues. RESULTS: there was no significant difference between SS-Control and RS-Control groups, SS-PTZ and SS-KEY groups, and RS-PTZ and RS-KEY groups (p>0.05) in none of the examined 4 parameters in liver and kidney tissues. The liver and kidney levels of MDA and NO in SS-PTZ group were found to be significantly higher than the SS-Control group (p<0.05). In SS-KEY group, the liver and kidney levels of MDA and NO were found to be significantly higher and GSH levels were significantly lower than the SS-Control group (p<0.05). While liver and kidney levels of MDA in RS-PTZ group and RS-KEY group were found to be significantly higher than the RS-Control group (p<0.05), liver and kidney GSH levels were significantly lower (p<0.05). The liver levels of NO in RS-PTZ group and RS-KEY group were found to be significantly higher than the RS-Control group (p<0.05). Kidney SOD activities in RS-PTZ group and RS-KEY group were found to be significantly lower than the RS-Control group (p<0.05). When RS-PTZ group is compared with the SS-PTZ group, the liver SOD activity and kidney NO level were found to be significantly lower in the RS-PTZ group (p<0.05). While the liver NO level and GSH level in RS-KEY group were significantly higher than the SS-KEY group, SOD activity was significantly lower in the RS-KEY group (p<0.05). When RS-KEY group was compared with SS-KEY group, the kidney NO level and SOD activity were found to be significantly lower in the RS-KEY group (p<0.05). CONCLUSION: in conclusion, key-ringing or PTZ induced single and repeated seizures result in increased oxidative damage and lipid peroxidation, and decreased antioxidant defense mechanisms.


Assuntos
Glutationa/metabolismo , Rim/metabolismo , Fígado/metabolismo , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Convulsões/patologia , Superóxido Dismutase/metabolismo , Estimulação Acústica/efeitos adversos , Análise de Variância , Animais , Convulsivantes/toxicidade , Modelos Animais de Doenças , Masculino , Pentilenotetrazol/toxicidade , Ratos , Ratos Wistar , Convulsões/etiologia
14.
J Med Syst ; 34(5): 967-73, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20703611

RESUMO

This paper presents the use of multiclass support vector machines (SVMs) for diagnosis of spirometric patterns (normal, restrictive, obstructive). The SVM decisions were fused using the error correcting output codes (ECOC). The multiclass SVM with the ECOC was trained on three spirometric parameters (forced expiratory volume in 1s--FEV1, forced vital capacity--FVC and FEV1/FVC ratio). The total classification accuracy of the SVM is 97.32%. The obtained results confirmed the validity of the SVMs to help in clinical decision-making.


Assuntos
Redes Neurais de Computação , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Insuficiência Respiratória/diagnóstico , Espirometria/instrumentação , Adulto , Volume Expiratório Forçado , Humanos , Masculino , Sensibilidade e Especificidade , Capacidade Vital
15.
J Med Syst ; 34(4): 643-50, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20703918

RESUMO

This paper presents the use of recurrent neural networks (RNNs) for diagnosis of carpal tunnel syndrome (CTS) (normal, right CTS, left CTS, bilateral CTS). The RNN is trained with the Levenberg-Marquardt algorithm. The RNN is trained on the features of CTS (right median motor latency, left median motor latency, right median sensory latency, left median sensory latency). The multilayer perceptron neural network (MLPNN) is also implemented for comparison the performance of the classifiers on the same diagnosis problem. The total classification accuracy of the RNN is significantly high (94.80%). The obtained results confirmed the validity of the RNNs to help in clinical decision-making.


Assuntos
Síndrome do Túnel Carpal/diagnóstico , Síndrome do Túnel Carpal/fisiopatologia , Diagnóstico por Computador , Condução Nervosa/fisiologia , Redes Neurais de Computação , Estudos de Casos e Controles , Eletromiografia , Feminino , Humanos , Masculino , Sensibilidade e Especificidade
16.
J Med Syst ; 34(3): 281-90, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20503612

RESUMO

This paper illustrates the use of mixture of experts (ME) network structure to guide model selection for diagnosis of two subtypes of adult hydrocephalus (normal-pressure hydrocephalus-NPH and aqueductal stenosis-AS). The ME is a modular neural network architecture for supervised learning. Expectation-Maximization (EM) algorithm was used for training the ME so that the learning process is decoupled in a manner that fits well with the modular structure. To improve classification accuracy, the outputs of expert networks were combined by a gating network simultaneously trained in order to stochastically select the expert that is performing the best at solving the problem. The classifiers were trained on the defining features of NPH and AS (velocity and flux). Three types of records (normal, NPH and AS) were classified with the accuracy of 95.83% by the ME network structure. The ME network structure achieved accuracy rates which were higher than that of the stand-alone neural network models.


Assuntos
Sistemas Inteligentes , Hidrocefalia/classificação , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Adolescente , Adulto , Idoso , Feminino , Humanos , Hidrocefalia/diagnóstico , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Adulto Jovem
17.
Comput Biol Med ; 39(3): 294-300, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19230874

RESUMO

A feature is a distinctive or characteristic measurement, transform, structural component extracted from a segment of a pattern. Features are used to represent patterns with the goal of minimizing the loss of important information. The discrete wavelet transform (DWT) as a feature extraction method was used in representing the spike-wave discharges (SWDs) records of Wistar Albino Glaxo/Rijswijk (WAG/Rij) rats. The SWD records of WAG/Rij rats were decomposed into time-frequency representations using the DWT and the statistical features were calculated to depict their distribution. The obtained wavelet coefficients were used to identify characteristics of the signal that were not apparent from the original time domain signal. The present study demonstrates that the wavelet coefficients are useful in determining the dynamics in the time-frequency domain of SWD records.


Assuntos
Encéfalo/patologia , Eletroencefalografia/métodos , Processamento de Sinais Assistido por Computador , Algoritmos , Animais , Eletrodos Implantados , Epilepsia/terapia , Masculino , Modelos Estatísticos , Ratos , Ratos Wistar , Fatores de Tempo
18.
Int J Neurosci ; 118(7): 981-93, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18569155

RESUMO

The aim of this study was to investigate neuron-specific enolase (NSE) immunoreactivity of the different brain regions after pentylenetetrazol (PTZ)- induced epileptic seizures in rats. Light microscopic examinations provided evidences for changes of neuronal activity after single and repeated seizures. The number of NSE (+) cells was well correlated with Nissl staining. The results suggest that NSE immunoreactivity may be a valuable marker for determination of the number of metabolically active neurons in different brain regions after single and repeated experimental seizures.


Assuntos
Encéfalo/enzimologia , Epilepsia/enzimologia , Fosfopiruvato Hidratase/metabolismo , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Encéfalo/anatomia & histologia , Encéfalo/fisiopatologia , Mapeamento Encefálico , Convulsivantes/farmacologia , Relação Dose-Resposta a Droga , Metabolismo Energético/fisiologia , Epilepsia/induzido quimicamente , Epilepsia/fisiopatologia , Imuno-Histoquímica , Masculino , Neurônios/enzimologia , Pentilenotetrazol/farmacologia , Valor Preditivo dos Testes , Ratos , Ratos Wistar
19.
Artigo em Inglês | MEDLINE | ID: mdl-19163760

RESUMO

In this paper, the discrete wavelet transform (DWT) as a feature extraction method was used in representing the spike-wave discharges (SWD) records of WAG/Rij rats. The SWD records of WAG/Rij rats were decomposed into time-frequency representations using the DWT and the statistical features were calculated to depict their distribution. The obtained wavelet coefficients were used to identify characteristics of the signal that were not apparent from the original time domain signal. The present study demonstrates that the wavelet coefficients are useful in determining the dynamics in the time-frequency domain of SWD records.


Assuntos
Eletroencefalografia/estatística & dados numéricos , Algoritmos , Animais , Clorpromazina/uso terapêutico , Interpretação Estatística de Dados , Eletrodos , Eletrodos Implantados , Eletroencefalografia/efeitos dos fármacos , Eletroencefalografia/métodos , Ketamina/uso terapêutico , Masculino , Modelos Estatísticos , Modelos Teóricos , Ratos , Ratos Wistar , Reprodutibilidade dos Testes
20.
Exp Biol Med (Maywood) ; 230(7): 501-5, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15985626

RESUMO

In the present study, we investigated the effects of micro-injecting 2-chloroadenosine (2-CADO; an adenosine receptor agonist) into the thalamus alone and with theophylline (a nonspecific adenosine receptor antagonist) pretreatment on pentylenetetrazol (PTZ)-induced tonic-clonic seizures in male Wistar albino rats. Following intrathalamic 2-CADO injection alone or theophylline pretreatment, 50 mg kg(-1) PTZ was given ip after 1 and 24 hrs. The duration of epileptic seizure activity was recorded by cortical electroencephalogram (EEG), and seizure severity was behaviorally scored. Intrathalamic 2-CADO administration induced significant decreases in both seizure duration and seizure severity scores at 1 and 24 hrs, but the effects were more abundant on the seizures induced after 24 hrs. On the other hand, pretreatment with theophylline prevented the inhibitor effect of 2-CADO on seizure activity and increased both seizure duration and seizure scores. Present results suggest that the activation of adenosine receptors in the thalamus may represent another anticonvulsant/modulatory site of adenosine action during the course of the PTZ-induced generalized tonic-clonic seizures and provide additional data for the involvement of the adenosinergic system in the generalized seizures model.


Assuntos
2-Cloroadenosina/uso terapêutico , Anticonvulsivantes/uso terapêutico , Agonistas do Receptor Purinérgico P1 , Convulsões/prevenção & controle , Tálamo/efeitos dos fármacos , 2-Cloroadenosina/administração & dosagem , 2-Cloroadenosina/farmacologia , Animais , Anticonvulsivantes/administração & dosagem , Eletroencefalografia , Masculino , Pentilenotetrazol/farmacologia , Antagonistas de Receptores Purinérgicos P1 , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Tálamo/fisiologia , Teofilina/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...