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Signal decomposition in surface electromyography
Vodhánilová, Edita ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
This thesis describe decomposition of electromyographic signal into its constituent motor unit action potential trains. A size and a shape of the action potencials can provide an important information about neuromuscular function. There are described the basics of neurophysiology and physiology of muscle in the theoretic section. Mainstay part of the thesis is description of electromyography and chapter about decomposition of electromyogprahy signal, where is introduced a method of decomposition and algorithms used for decomposition. In practical part is tested a robustness of algorithms, which are contained in program called EMGLAB. The trial is performed with three different signal and results are assessed and compared by the statistical methods ANOVA and paired t-test. Key words: action potencial, EMG signal, electromyography, decomposition, EMGLAB
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Discrimination of EMG signals from individual forearm muscles from surface EMG.
Krásná, Jana ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Title: Discrimination of EMG signals from individual forearm muscles from surface EMG Abstract: Location of electrodes for sensing the forearm muscles using surface electromyography is not accurately described. It is based only on recommendations by various authors in making researches. The aim of this study was to determine the optimal placement of electrodes on the forearm and describe it to another repeatable measurements. By analyzing the amplitude of EMG recording is confirmed not only the optimal location of electrodes, but either suggested muscle synergies that are possible to analyze more deeply in other studies because a detailed examination of muscle synergies are considerable application in upper limb prosthetics Keywords: Surface electromyography, forearm muscles, amplitude analysis
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Impairment of cellular metabolism as common pathophzsiological mechanism of CNS diseases
Hasala, Ondřej ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Name of thesis: Impairment of cellular metabolism as common pathophysiological mechanism of CNS diseases Problem definition: Every human cell needs energy for living. If the prodcution of ATP (as an universal energy carrier) is broken, cell restricts its activity first and during longterm depletion of ATP, dies. It was found, that cellular metabolism is broken in most pathologies in CNS. Disorder of respiratory chain by free radicals is the best known at Parkinson's disease, epilepsy, brain ischemia etc. Mitochondria, where respiratory chain is situated, is not only the aim of free radicals, but it is their major producer. The activity of respiratory chain decreases during the life and this phenomenan is called aging. Aim of thesis: To determine whether there is increased production of free radicals in mitochondria of rat (LE Wistar) hippocampus during the epileptic seizure. Method: Thesis involves experiment which was done with acute rat hippocampal slices. To induce epileptic seizure it was used 4-aminopyridine model. It was used fluorescence imaging as imaging method. Changes of superoxide production was detected with MitoSOX. Electrophysiological record was taken by programme Spike 2 with stimulation and recording electrode inside the slice. Results: There was no significant difference between...
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Angle in the joint and H-reflex
Stiborová, Pavla ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Title: H-reflex, depending on the position of the joint Aim: The aim of this study is to determine whether the position of the ankle joint influences the parameters of the soleus muscle H-reflex. We are interested in a change of amplitude, latency and threshold of the H-reflex. Method: To measure H-reflex, we have used surface elektromygraphy. We examined two different positions of the foot in probands lying on the bed on their stomach. The first position was with the feet out of bed, around 90 degrees at the ankle joint (rest position). At the second position, the foot moved the bed and was in position in plantar flexion. Stimulation were performed over the tibial nerve in the popliteal fossa. The response, we recorded the surface electrode over the soleus muscle. Results: By changing the position of the ankle from rest to plantar flexion there was no statistically significant changes in amplitude, latency or threshold of the H-reflex. In plantar flection, we found a reduction of Hmax/Mmax ratio, which is probably due to reduced excitability alpha motoneurons through reciprocal ihibition from stretched muscle of the leg. Keywords: H-reflex, soleus muscle, joint position, surface EMG
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Optical Signals of Brain
Konopková, Renata ; Otáhal, Jakub (advisor) ; Kittnar, Otomar (referee) ; Valeš, Karel (referee)
Intrinsic optical signals are the signals reflecting changes in transmittance or reflectance of the light illumitating the tissue. Registration of such changes can be applied for the detection of physiological condition in the slices of biological tissues (in vitro) or in the whole animal (in vivo). The aim of this project is to introduce this topic and show different possibilities for the detection of changing optical properties of nervous tissue both in vitro and in vivo. The detection system of both light source and attachment of the optical fibre to the skull of the animal for in vivo experimets have been designed. The proper experimental part of the study have been done in hippocampal tissue slices and shows the correlation of the tissue activity and the optical signal at level of ion channels, glutamatergic synaptic activity, glial component of the signal and mitochondrial signal. We are dealing with the source of the noice that we record while detecting rather subtle changes of optical properties. We are indroducing the software VisionBrain for synchronous detection of both electrical and optical changes. Keywords: Intrinsic optical signals, hippocampus, imaging, biomechanics
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Damage to oligodendrocytes and axons following endothelin 1 - induced focal cerebral ischemia
Brožíčková, Carole ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Aims: The purpose of this study was to characterize the regional patterns of neuronal and axonal injury in immature rats following FCI. Methods: Experiments were performed in Wistar rats on postnatal day 12 and 25. FCI was induced by the intracerebral injection of Endothelin 1 (ET-1). Neuronal and axonal injury was assessed by the means of qualitative morphologic methods. Results: Our findings demonstrate that ET-1 induced FCI in the developing rat brain generates neuronal injury in the ipsilateral cortex and a distinct pattern of subcortical neuronal injury. The spatial spread of the damage to myelinated fibers seemed to be bigger than the extent of the area, where degenerating neurons were observed. Keywords: Oligodendrocyte, Focal cerebral ischemia, Endothelin-1, Myelin
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Anterograde tracing - a method for detection of plasticity of neuronal tracts
Krausová, Zuzana ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Title of work: Anterograde tracing - method for detecting conversion neuronal pathways in CNS focal lesion Objective: Create a suitable methodology for dyeing commissural fibers and its future use it to evaluate the plasticity of nerve tissue and confirmed using the anterograde tracer detecting fibers from the application site of the tracer in the contralateral projection area. Method: The experiment was carried out on adult individuals of the rat, which It was applied anterograde tracer BDA. Then we watched the ability of the tracer color commissural nerve fibers and fibers on the behavior of the application site in sensorimotor cortex. Results show that Biotinylated dextran amine is capable as anterograde tracer color neurons and fibers in the puncture cannula. However, our experiment It proves that BDA is suitable for marking commissural connections from the application site contralateral. Key words: focal cerebral ischemia, anterograde tracing, BDA, white matter, plasticity nervous tissue Powered by TCPDF (www.tcpdf.org)
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Detection of neuronal pathways after CNS lesions by using dextran amine.
Muchová, Zuzana ; Konopková, Renata (referee) ; Otáhal, Jakub (advisor)
Title of work: Detection of neuronal pathways after CNS lesions by using dextran amine. Aim: Develop a metodology for pathway tracing with the substance transmitted by axonal anterograde transport and compare iontophoretic and pressure injection of BDA. Methods: The experiment was performed on adult rats which where injected iontophoretic and pressure anterograde tracer BDA. One week after injection were decapitated in deep anesthesia, their brains removed, frozen in dry ice and stored at -70řC. The brains were then cut into thin coronal slice (50 µm), immunolabeled and loaded on microscopic slides. Individual sections were examined labeling nerve fibers at the injection site, its surroundings and contralateral side of the hemisphere. Results: After injections of anterograde tracer BDA into the nervous tissue have been shown labeling of nerve fibers at the injection site, surroundings and contralateral side of the hemisphere. As an efficient method for its injection was determined according to results of the pressure method. Key words: anterograde tracer, BDA, iontophoretic injection, cerebral ischemia, neuroplasticity
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Electrophysiological Models of Seizure like Activity for NO Detection in Vitro
Novák, Karel ; Konopková, Renata (referee) ; Otáhal, Jakub (advisor)
Definition of work: Electrophysiological models of seizure like activity for NO detection in vitro Supervisor: MUDr. Jakub Otáhal, PhD. Department of Anatomy and Biomechanics FTVS CUNI Department of Developmental Epileptology CAS, Institute of Physiology Consultant: Mgr. Renata Konopková Department of Developmental Epileptology CAS, Institute of Physiology Aim: The aim of the thesis is to introduce nitric oxide (NO) and its role in physiology and pathophysiolgy of central nervous system (CNS), with the intention of epileptiform activity in the nervous tissue. Our research was realized on rat hippocampal slices in vitro and it compares the experimental biochemical models (low-Mg2+ , high-K+ , Carbachol, Bicuculline and 4-Aminopyridine model). These changes in the environment of slice should evoke the epileptiform activity in the nervous tissue of the rat. The final aim of the thesis is to create an experimental model of epileptiform activity in vitro in our setup for imaging techniques and NO detection. Methods: Experiments were performed in rat hippocampal slices in vitro. Rats were deeply anaesthetized with ether and decapitated. Brain was rapidly removed from the scull, cut in oxygenated (95%) and cooled (0, 5 řC) artificial cerebrospinal fluid (ACSF) using vibratome in coronal slices of 400µm of...
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Method for assesment of the effect of selected anesthetics on H-reflex in laboratory rat.
Komárková, Mariana ; Otáhal, Jakub (advisor) ; Konopková, Renata (referee)
Title of work: Method for Assesment of the Effect of Selected Anesthetics on H-reflex in Laboratory Rat Objective: To create an applicable method for recording of the H-reflex of freely moveable unanesthetized rats. Methods: Three adult rats were each implanted in the right leg with stimulating electrodes in a flexible cuff on the tibial nerve and a pair of recording electrodes in the triceps surae muscle. After recovering it was evaluated if the electrodes are appropriate for stimulation of peripheral nerve and for recording of ongoing EMG and evoked EMG (H-reflex, M- response). Results: It is possible to use stimulating electrodes in a flexible cuff and a pair of recording electrodes for recording ongoing EMG and evoked EMG (H-reflex, M-response) in freely moveable rats. The experiment did not determine which kind of metal is the most appropriate for conductor for recording high quality EMG. Keywords: H-reflex, Electromyography, Implanted electrodes, Rat, Electrophysiology
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