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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
391

The role of monoamines in post traumatic stress disorder (PTSD) using a time dependent sensitization animal model / Zakkiyya Igbal Jeeva

Jeeva, Zakkiyya Igbal January 2004 (has links)
Posttraumatic stress disorder (PTSD) is an anxiety disorder that may result from an exposure to a severely traumatic life-event. It is characterised by a delayed onset of psychological and physical symptoms including re-experiencing the event, avoidance of reminders associated with the trauma, increased autonomic arousal and distinct memory deficits. This disorder is also characterised by a maladaptive hypothalamic-pituitary-adrenal (HPA)-axis response and altered monoamine concentrations in the hippocampus and pre-frontal cortex. The Time Dependent Sensitization (TDS) model is a putative animal model of PTSD that is based on the concept of repeated trauma, using three acute stressors (TS) of intense severity followed by a mild situational reminder (RS) on day 7 subsequent to the acute stressors. The aims of this study were to determine if the Triple Stressor (TS) induces stress and if the situational reminder (RS) is necessary for the maintenance of the stress response over time and whether these two stress responses are qualitatively and quantitively different. This was done to further validate the TDS model and to characterize the development and progression of the stress-related pathology of PTSD. Methods used were High Performance Liquid Chromatography (HPLC) with electrochemical detection (biochemical correlates) for quantifying the monoamines dopamine (DA), noradrenaline (NA) and serotonin (5-HT) concentrations in the hippocampus and pre-frontal cortex (PFC); radio immuno assay (RIA) for the determination of plasma corticosterone concentrations (neuroendocrine parameter) and the use of the Elevated Plus Maze (EPM) to detect anxiety-like behaviour (behavioural analyses). The study was subdivided into an Acute and Re-Stress study (n = 10). In the Acute Study rats were exposed to TS as the only stressor. Group 1 was sacrificed immediately after TS, Group 2 was sacrificed 3 days post TS and Group 3 on day 7 post TS. In the Re-Stress Study both TS and RS were used as stressors. Group 4 was sacrificed immediately after the situational reminder, Group 5 was sacrificed 3 days post RS and Group 6 on day 7 post RS. A group of unstressed rats were used as Control. The results of this study found corticosterone concentrations elevated immediately after the TS (p<0.05). Exposure to the RS resulted in a profound hypocortisolism (p<0.05). These results indicate a possible disturbance in the regulation of the HPA-axis, which manifests as an enhanced negative feed-back upon re-introduction of the stressful situation. Changes in MA concentrations were evident. Although no definite fixed trend is apparent in this study, it is evident that the TDS model does induce monoamine dysregulation. Hippocampal NA. DA and 5-HT concentrations were noted to be elevated on day 7 post TS (p<0.05). On day 7 post RS only hippocampal 5HT was decreased significantly (p<0.05). Behavioural analyses indicate that stress related anxiety was not sustained after the TS but 7 days after the exposure to the RS rats were most anxious (p<0.05). The results confirm that the TDS model does induce PTSD-like symptoms in rats and that the situational reminder (RS) is necessary for the maintenance of the stress response. This model may be useful in the investigation of future experimental pharmacological interventions in the management of PTSD. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2005.
392

The role of monoamines in post traumatic stress disorder (PTSD) using a time dependent sensitization animal model / Zakkiyya Igbal Jeeva

Jeeva, Zakkiyya Igbal January 2004 (has links)
Posttraumatic stress disorder (PTSD) is an anxiety disorder that may result from an exposure to a severely traumatic life-event. It is characterised by a delayed onset of psychological and physical symptoms including re-experiencing the event, avoidance of reminders associated with the trauma, increased autonomic arousal and distinct memory deficits. This disorder is also characterised by a maladaptive hypothalamic-pituitary-adrenal (HPA)-axis response and altered monoamine concentrations in the hippocampus and pre-frontal cortex. The Time Dependent Sensitization (TDS) model is a putative animal model of PTSD that is based on the concept of repeated trauma, using three acute stressors (TS) of intense severity followed by a mild situational reminder (RS) on day 7 subsequent to the acute stressors. The aims of this study were to determine if the Triple Stressor (TS) induces stress and if the situational reminder (RS) is necessary for the maintenance of the stress response over time and whether these two stress responses are qualitatively and quantitively different. This was done to further validate the TDS model and to characterize the development and progression of the stress-related pathology of PTSD. Methods used were High Performance Liquid Chromatography (HPLC) with electrochemical detection (biochemical correlates) for quantifying the monoamines dopamine (DA), noradrenaline (NA) and serotonin (5-HT) concentrations in the hippocampus and pre-frontal cortex (PFC); radio immuno assay (RIA) for the determination of plasma corticosterone concentrations (neuroendocrine parameter) and the use of the Elevated Plus Maze (EPM) to detect anxiety-like behaviour (behavioural analyses). The study was subdivided into an Acute and Re-Stress study (n = 10). In the Acute Study rats were exposed to TS as the only stressor. Group 1 was sacrificed immediately after TS, Group 2 was sacrificed 3 days post TS and Group 3 on day 7 post TS. In the Re-Stress Study both TS and RS were used as stressors. Group 4 was sacrificed immediately after the situational reminder, Group 5 was sacrificed 3 days post RS and Group 6 on day 7 post RS. A group of unstressed rats were used as Control. The results of this study found corticosterone concentrations elevated immediately after the TS (p<0.05). Exposure to the RS resulted in a profound hypocortisolism (p<0.05). These results indicate a possible disturbance in the regulation of the HPA-axis, which manifests as an enhanced negative feed-back upon re-introduction of the stressful situation. Changes in MA concentrations were evident. Although no definite fixed trend is apparent in this study, it is evident that the TDS model does induce monoamine dysregulation. Hippocampal NA. DA and 5-HT concentrations were noted to be elevated on day 7 post TS (p<0.05). On day 7 post RS only hippocampal 5HT was decreased significantly (p<0.05). Behavioural analyses indicate that stress related anxiety was not sustained after the TS but 7 days after the exposure to the RS rats were most anxious (p<0.05). The results confirm that the TDS model does induce PTSD-like symptoms in rats and that the situational reminder (RS) is necessary for the maintenance of the stress response. This model may be useful in the investigation of future experimental pharmacological interventions in the management of PTSD. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2005.
393

A pharmacokinetic-pharmacodynamic relationship study between GABA-ergic drugs and anxiety levels in an animal model of PTSD / Jacolene Myburgh

Myburgh, Jacolene January 2005 (has links)
Posttraumatic stress disorder (PTSD) is classified as an anxiety disorder and the characteristic symptoms (re-experiencing, avoidance as well as numbing of general responsiveness and hyperarousal) of this disorder develop in response to a traumatic event. The disorder is characterised by hypothalamic-pituitary-adrenal (HPA) axis abnormalities linked with changes in cortisol moreover, the hippocampus and cortex also play a role in the neurobiology. With regard to the neurochemistry of this disorder it is known that gamma amino butyric acid (GABA) is involved however, the precise role of GABA in PTSD and how stress changes GABA concentrations in the brain are still not fully understood. Another aspect regarding PTSD that has not been clearly defined is the treatment of PTSD. Classic anxiolytics such as diazepam is expected to relieve the anxiety linked with PTSD. Studies with this group of drugs have however not produced the concrete evidence needed to establish it as a treatment of choice for PTSD and subsequently other classes of drugs have been investigated as possible treatment options for PTSD. Among these is lamotrigine, which in a clinical study was found to be effective in alleviating symptoms of PTSD. Moreover, a possible pharmacokinetic-pharmacodynamic relationship for each of these drugs has also not been elucidated. In order to elude on some of these uncertainties, an animal model of PTSD, time dependent sensitisation (TDS), was used. GABA levels in the rat hippocampus and frontal cortex were determined at two different time intervals following the TDS procedure (1 day and 7 days post re-stress). High performance liquid chromatography (HPLC) with electrochemical (EC) detection was used to determine gamma amino butyric acid (GABA) concentrations. To investigate the possible anxiolytic effects of diazepam and lamotrigine in this model, as well as a possible pharmacokinetic-pharmacodynamic relationship for each drug, pharmacokinetic profiles for both drugs were established in order to find the times of peak and trough levels of each drug. Blood samples were collected at different time intervals after drug administration either from the tail vein of rats (lamotrigine) or directly from the heart (diazepam). Subsequently, drug concentrations at each time interval were determined by means of HPLC with ultraviolet (UV) detection. The behaviour of rats was analysed using the elevated plus-maze (EPM) at peak or trough concentrations of the drugs and this was performed after either acute administration of the drug, or after a 14 day chronic treatment regime. GABA levels in the hippocampus were not found to change statistically significantly in response to stress at either 1 day or 7 days post re-stress. In the frontal cortex, however, GABA levels increased in response to stress at 1 day post re-stress, with a statistically insignificant, but strong trend towards an increase, at 7 days post re-stress. With regard to the pharmacokinetic profiles, the peak concentration of diazepam was found to occur at 60 minutes, with lamotrigine's peak at 120 minutes. The behavioural studies indicated that acute treatment with diazepam 3 mg/kg resulted in a statistically significant increase in both ratio open arm entries and ratio time spent in the open arms at peak level of the drug. After acute treatment with diazepam 3 mg/kg a statistically significant decrease in ratio time spent in open arms was also found when the ratio time spent in open arms at peak level of the drug and the ratio time spent in open arms at trough level of the drug was compared. In response to chronic treatment with diazepam 3 mg/kg for 14 days, test animals exhibited an increase in the ratio open arm entries at trough level of the drug, with a statistically insignificant yet definite trend towards an increase at peak level. Acute treatment with lamotrigine 10 mg/kg resulted in no statistically significant change in EPM parameters. In response to chronic treatment, however, a statistically significant increase was found in ratio time spent in open arms at peak level of the drug, with a statistically insignificant trend towards an increase at trough level. From the results of this study, we may therefore conclude that GABA-levels in the brain are definitely affected, but in different ways, following TDS-stress. A pharmacokinetic-pharmacodynamic relationship between the drugs' levels and aversive behaviour could also be established. Furthermore it appears that more sustained anxiolytic effects are evident following chronic treatment with both drugs than with acute administration of these drugs. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2006
394

A bio-behavioural investigation into the role of the cholinergic system in stress / Ilse Groenewald

Groenewald, Ilse January 2006 (has links)
Posttraumatic stress disorder (PTSD) is an anxiety disorder that may follow exposure to severe emotional trauma and presents with various symptoms of anxiety, hyperarousal and cognitive anomalies. Interestingly, only 10-30% of an exposed population will go on to develop full-blown PTSD. Cholinergic neurotransmission is implicated in anxiety as well as other typical manifestations of PTSD, particularly cognitive changes. The frontal cortex and hippocampus regulate and in turn are affected by stress, and have also been implicated in the underlying neuropathology of PTSD. These areas are densely innervated by cholinergic neurons originating from the basal forebrain. In this study, the time dependent sensitization (TDS) model was used to induce symptoms of PTSD in animals. The study was designed to determine the long-term effects of an intense, prolonged aversive procedure on central muscarinic acetylcholine receptor (mAChR) characteristics and the correlation if any of those findings to cognitive aspects and general arousal as characteristics associated with PTSD. In order to achieve this goal, male Sprague-Dawley rats were exposed to the TDS stress paradigm with behavioral/neuro-receptor assessments performed on day 7 post re-stress (duration of each experiment in whole is 14 days). Acoustic startle reflex (ASR) was used to determine emotional state (hyperarousal), while the conditioned taste aversion (CTA) paradigm was implemented in order to assess aversive memory. Muscarinic receptor binding studies were performed in the frontal cortex and hippocampus. Moreover, both the stress-exposed and control animals were pre-tested in the acoustic startle chamber in order to attempt to separate stress sensitive from stress-resilient animals based on predetermined ASR criteria. The ASR niodel was previously validated in our laboratory, while the CTA model was validated in this project before application. In the CTA model, an i.p. injection with lithium chloride (LiCl) (associated with digestive malaise), was used as unconditioned stimulus (US) and was paired with a saccharinlcyclamate drinking solution as conditioned stimulus (CS) to induce aversion to the novel taste (CS) when presented in the absence of the US. Population data of animals tested in the ASR experiment indicated no statistical significant difference between stressed and control animals. However, when each animal was assessed individually, 22.5 % of the exposed population displayed all increase above the predetermined criteria of 35 % in startle response, indicating a state of heightened arousal. In contrast, only 4.2 O h of control animals (no stress) displayed an increase in arousal based on the above mentioned criteria. Muscarinic receptor densities (Bm,) in the total population of animals exposed to stress showed a statistical significant increase in both the hippocampus and frontal cortex when compared to controls, with no changes in & values observed in either one of the areas. In the CTA experiment, TDS stress was implemented as US paired with a saccharinlcyclamate drinking solution as CS. An acute session of prolonged stress (as used in the TDS model) effectively induced aversion to a novel taste and a subsequent reminder of the stress (restress) paired with the CS sustained the acquire adversive memory. Furthermore, LiCl was reintroduced as US in order to assess the effect of prior exposure to two types of stress (acute and TDS) on subsequently acquired CTA memory. Prior exposure to acute stress had no significant effect on subsequently acquired aversive memory when measured either 3- or 7 days post-conditioning (CS-US). Stress-restress (TDS) exposure, however, indicated a significant decrease in aversive memory from 3- to 7 days post-conditioning (CS-US) as well as a significant decrease in aversive memory between the control- and the TDS group 7 days post-conditioning. The mAChR density (B,,) in the frontal cortex; but not in the hippocampus, was elevated at the same point in time (7 days post CS-US pairing) that CTA memory was impaired following TDS stress (stress-restress). Ultimately, these data support an association between altered cholinergic receptors and hyperarousallanxiety in an animal model of PTSD. The data also support the phenomenon of individual susceptibility to stress in animals that parallels that observed in humans exposed to severe trauma. Impaired aversive memory (CTA) is a consequence of prior exposure to TDS stress, but not acute stress, and is likewise mediated by an altered central cholinergic transmission displayed as an increase in mAChRs in the frontal cortex. The lack of studies regarding the influence of the cholinergic system in PTSD related behavior earns ,this project value as inimitable PTSD research. / Thesis (M.Sc. (Pharmacology))--North-West University, Potchefstroom Campus, 2007.
395

Lipreading across multiple views

Lucey, Patrick Joseph January 2007 (has links)
Visual information from a speaker's mouth region is known to improve automatic speech recognition (ASR) robustness, especially in the presence of acoustic noise. Currently, the vast majority of audio-visual ASR (AVASR) studies assume frontal images of the speaker's face, which is a rather restrictive human-computer interaction (HCI) scenario. The lack of research into AVASR across multiple views has been dictated by the lack of large corpora that contains varying pose/viewpoint speech data. Recently, research has concentrated on recognising human be- haviours within &quotmeeting " or &quotlecture " type scenarios via &quotsmart-rooms ". This has resulted in the collection of audio-visual speech data which allows for the recognition of visual speech from both frontal and non-frontal views to occur. Using this data, the main focus of this thesis was to investigate and develop various methods within the confines of a lipreading system which can recognise visual speech across multiple views. This reseach constitutes the first published work within the field which looks at this particular aspect of AVASR. The task of recognising visual speech from non-frontal views (i.e. profile) is in principle very similar to that of frontal views, requiring the lipreading system to initially locate and track the mouth region and subsequently extract visual features. However, this task is far more complicated than the frontal case, because the facial features required to locate and track the mouth lie in a much more limited spatial plane. Nevertheless, accurate mouth region tracking can be achieved by employing techniques similar to frontal facial feature localisation. Once the mouth region has been extracted, the same visual feature extraction process can take place to the frontal view. A novel contribution of this thesis, is to quantify the degradation in lipreading performance between the frontal and profile views. In addition to this, novel patch-based analysis of the various views is conducted, and as a result a novel multi-stream patch-based representation is formulated. Having a lipreading system which can recognise visual speech from both frontal and profile views is a novel contribution to the field of AVASR. How- ever, given both the frontal and profile viewpoints, this begs the question, is there any benefit of having the additional viewpoint? Another major contribution of this thesis, is an exploration of a novel multi-view lipreading system. This system shows that there does exist complimentary information in the additional viewpoint (possibly that of lip protrusion), with superior performance achieved in the multi-view system compared to the frontal-only system. Even though having a multi-view lipreading system which can recognise visual speech from both front and profile views is very beneficial, it can hardly considered to be realistic, as each particular viewpoint is dedicated to a single pose (i.e. front or profile). In an effort to make the lipreading system more realistic, a unified system based on a single camera was developed which enables a lipreading system to recognise visual speech from both frontal and profile poses. This is called pose-invariant lipreading. Pose-invariant lipreading can be performed on either stationary or continuous tasks. Methods which effectively normalise the various poses into a single pose were investigated for the stationary scenario and in another contribution of this thesis, an algorithm based on regularised linear regression was employed to project all the visual speech features into a uniform pose. This particular method is shown to be beneficial when the lipreading system was biased towards the dominant pose (i.e. frontal). The final contribution of this thesis is the formulation of a continuous pose-invariant lipreading system which contains a pose-estimator at the start of the visual front-end. This system highlights the complexity of developing such a system, as introducing more flexibility within the lipreading system invariability means the introduction of more error. All the works contained in this thesis present novel and innovative contributions to the field of AVASR, and hopefully this will aid in the future deployment of an AVASR system in realistic scenarios.
396

Papel do cortex pré-frontal medial no comportamento defensivo de camundongos : avaliação farmacológica da lateralização funcional

Costa, Nathália Santos 13 April 2017 (has links)
Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-08-23T19:35:48Z No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-23T19:35:55Z (GMT) No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-23T19:36:03Z (GMT) No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) / Made available in DSpace on 2017-08-23T19:36:10Z (GMT). No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) Previous issue date: 2017-04-13 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Stressful situations are risk factors to the development of neuropsychiatric diseases, as anxiety disorders. However, not everyone who experiences stressful events develops stress-related illness. That is due to the existence of differences in the ability to adapt to stress, that is, the manifestation of susceptibility or resilience phenotypes. The search for understanding neural systems involved to these differences has evidenced an important role of the medial Prefrontal Cortex (mPFC), and, recently, its functional lateralization has been highlighted. In this sense, the right mPFC (RmPFC) seems to modulate anxiogenic-like responses, while the left mPFC (LmPFC) would attenuate such responses, thereby facilitating animals to cope with threatening situations. If so, LmPFC inhibition would intensify ansiogenic-like behavior front to aversive stimuli. Under this hypothesis, one of the goals of the present study was to investigate whether the inhibition of the LmPFC could modulate the effect of two types of stress (the restraint and the social defeat) on anxiety. Yet, we also aimed to investigate whether NMDA-glutamate receptor would be involved to the anxiogenic-like effect induced by nitrergic activation of the RmPFC, given the anxiogenic potential of glutamate and the interaction already known between these neurotransmissions. To reach that, experiments were carried out (1) to characterize the effects of social defeat and restraint stress on animals exposed to elevated plus maze (EPM) 5 minutes or 24 hours later; (2) to evaluate the effects of restraint or social defeat combined to the synaptic inactivation (through nonspecific inhibitor, CoCl2) of the LmPFC on the defensive behavior of mice exposed to EPM 24 h after stress; (3) to investigate the effects of NMDA receptor antagonism and (4) the effect of that antagonism on anxiogenic-like effects induced by NO donor. The results showed that both restraint and defeat stress are anxiogenic at 5 minutes, but defeated mice do not display anxiety 24 h after stress. Furthermore, the synaptic inhibition produced a clear anxiogenic-like effect in defeated (but not restrained) mice. In addition, the blockade of NMDA receptors produced anxiolytic-like effects and reversed the anxiogenic effect induced by NO injection into the RmPFC. Taken together, these results corroborate previous studies demonstrating the functional lateralization of the mPFC, in which the right and left hemispheres seem to have distinct roles in the modulation of aversive events. / O estresse, que pode ser definido como uma condição que perturba o equilíbrio fisiológico e psicológico de um indivíduo, é fator de risco para o desenvolvimento de doenças neuropsiquiáticas, como transtornos de ansiedade. No entanto, nem todos os indivíduos que vivenciam um evento estressor desenvolvem doenças relacionadas a ele. Isto se deve à existência de diferenças na habilidade de se adaptar ao estresse, ou seja, a manifestação dos fenótipos de susceptibilidade ou resiliência. A busca pelo entendimento dos sistemas neurais envolvidos nessas diferenças tem evidenciado um papel importante do Córtex Pré-Frontal medial (CPFm) e, mais recentemente, a sua lateralização funcional vem ganhando especial destaque. Neste sentido, o CPFm Direito (D) parece modular respostas ansiogênicas, enquanto o CPFm Esquerdo (E) atenuaria essas respostas, ajudando o animal a lidar com eventos aversivos. Neste caso, a inibição do CPFmE intensificaria as respostas geradas por situações ameaçadoras. Sob essa hipótese, um dos objetivos do presente trabalho foi investigar se a inibição do CPFmE poderia modular o efeito de dois tipos de estresse (a contenção e a derrota social) sobre a ansiedade. Ainda, esse estudo também investigou se os receptores glutamatérgicos do tipo NMDA (N-metil-D-aspartato) estariam envolvidos no efeito ansiogênico provocado pela ativação nitrérgica [com injeção local do doador de óxido nítrico (NO), o NOC-9] no CPFmD, haja vista o potencial ansiogênico do glutamato e as interações já conhecidas entre essas neurotransmissões. Para tanto, foram feitos experimentos para (1) caracterizar os efeitos imediatos (após 5 minutos) ou tardios (após 24 horas) do estresse de derrota social e de contenção sobre o comportamento de animais expostos ao labirinto em cruz elevado (LCE); (2) avaliar os efeitos da combinação do estresse de contenção ou de derrota social com a inativação sináptica (através do inibidor inespecífico, CoCl2) do CPFm E no comportamento defensivo de camundongos expostos ao LCE 24h após o evento estressor; (3) investigar os efeitos do antagonismo per se de receptores NMDA e (4) o efeito desse antagonismo sobre a ansiogênese provocada pelo doador de NO sobre o comportamento de animais expostos ao LCE. Os resultados obtidos demonstram que ambos os estressores são ansiogênicos aos 5 minutos, mas a derrota social não provoca aumento de ansiedade 24 h após o estresse. Ainda, a inbição sináptica do CPFmE produz efeito ansiogênico 24 h depois quando associada ao estresse de derrota social (mas não à contenção). Além disso, o bloqueio de receptores NMDA por si provoca efeito ansiolítico e reverte o efeito ansiogênico provocado pelo NO em animais expostos ao LCE. Tomados em conjunto, esses resultados substanciam as evidências sobre a lateralização funcional do CPFm, em que os hemisférios direito e esquerdo parecem possuir diferentes participações na modulação de eventos aversivos.
397

Análise neuroquímica e morfométrica de culturas de neurônios corticais do modelo murino do TDAH

Marques, Daniela Melo January 2018 (has links)
O Transtorno de Déficit de Atenção e Hiperatividade (TDAH) é um dos transtornos neuropsiquiátricos mais prevalentes da infância caracterizado pelos sintomas de desatenção, hiperatividade e impulsividade. O TDAH é uma desordem neurocomportamental heterogênea e fenotipicamente complexa e sua etiologia ainda não foi completamente esclarecida, mas sabe-se que a interação de fatores ambientais e genéticos e o acúmulo de seus efeitos possivelmente aumenta a vulnerabilidade ao transtorno. Nesse estudo, foram investigados o imunoconteúdo de proteínas sinápticas e do desenvolvimento a partir de neurônios da região do córtex pré-frontal de animais SHR, um dos modelos animais mais validados para o estudo do TDAH. Também foi realizada uma análise morfomética do padrão de desenvolvimento dessas células ao longo de diferentes dias in vitro e o papel do BDNF, fator neurotrófico crucial para a sobrevivência e maturação das sinapses, no desenvolvimento dos neurônios SHR. A análise do imunoconteúdo da SNAP-25 mostrou aumento nos níveis dessa proteína no 2º DIV e diminuição no 5º DIV nos neurônios SHR em relação ao controle WKY, sem alterações entre as cepas nos outros dias analisados. Em relação aos níveis de sinaptofisina nos neurônios SHR, foi observado aumento somente no 5º DIV. A análise do proBDNF mostrou diminuição nos neurônios SHR no 5º DIV e aumento no 8º DIV. A imunodetecção do CREB mostrou que os neurônios SHR apresentam níveis diminuídos dessa proteína somente no 1º DIV. O receptor TrkB também apresentou alterações no seu imunoconteúdo, com aumento no 2º DIV e diminuição no 5º DIV nos neurônios SHR. O imunoconteúdo do BDNF e do TrkB fosforilado não apresentaram alterações entre as linhagens nos dias analisados. Além disso, foi realizada uma análise morfométrica de diferentes parâmetros de desenvolvimento dos neurônios ao longo de diferentes dias in vitro por meio da marcação da proteína da região somatodendrítica MAP-2. Foi observada diminuição no comprimento total dos neuritos dos neurônios SHR no 5º DIV em relação aos neurônios WKY. Também foi verificado redução no número de raízes no 2º DIV e redução no número de pontos de ramificação no 5º DIV nos neurônios SHR. As alterações observadas em proteínas que são relacionadas aos processos de sinapses e de desenvolvimento neuronal podem auxiliar na compreenssão das diferenças encontradas no padrão de desenvolvimento dos neurônios SHR. Essas modificações a nível proteico podem estar alterando o crescimento e o padrão de arborização dendrítica e implicar em modificações na funcionalidade dessas células importantes para a melhor compreensão das bases neurobiológicas do TDAH. / Attention deficit hyperactivity disorder (ADHD) is one of the most common neuropsychiatric disorders of childhood characterized by symptoms of inattention, hyperactivity and impulsivity. ADHD is a heterogeneous and phenotypically complex neurobehavioral disorder with unknown etiology, but the interaction between environmental and genetic factors have been described to increase the vulnerability to the disorder. In this study, we investigated the immunocontent of synaptic and development proteins of prefrontal cortex neurons from one of the most validated animal models for the study of ADHD (SHR). We also performed a morphometric analysis along development of these cells at different days in vitro and the role of a neurotrofic factor (BDNF) in neuronal outgrowth. SNAP-25 immunocontent was increased at 2 DIV and decreased at 5 DIV in SHR neurons. Synaptophysin levels show increases only at 5 DIV in SHR neurons. The levels of proBDNF were decreased at 5 DIV and increased at 8 DIV in SHR neurons. CREB immunodetection showed that SHR neurons present decreased levels only at 1 DIV. The TrkB receptor also presented changes in immunocontent, with increase at 2 DIV and decrease at 5 DIV in the SHR neurons. Morphometric analysis during neuronal development by immunostaining with MAP-2 somatodendritic protein show decrease in total length at 5 DIV in SHR neurons in relation to WKY neurons. Besides that, SHR neurons exhibit reduction in number of roots at 2 DIV and number of branch points at 5 DIV. Changes in proteins related to synaptic processes and neuronal during development can help to understand differences found in the pattern of development of the neurons SHR. These changes at protein level may be altering neuronal outgrowth and dendritic arborization and possible involve modifications in functionality of these cells important for better understanding the neurobiological bases of ADHD.
398

Vodní režim rostlin jako výukové téma v badatelsky orientovaném vyučování na gymnáziu / Water regime of plants as a learning topic in inquiry-based education at grammar school

BEZPALCOVÁ, Eva January 2015 (has links)
The aim of the diploma thesis was to create educational presentation for grammar school students according to the inquiry-based education principles and used in the classroom for teaching the thematic unit Water regime of plants, its application in teaching process and inclusion of inquiry-based education into plant physiology lessons at grammar school. A comparative survey which included 90 students was carried out in three first grade parallel classes. The level of students´knowledge was compared on a basis of the achievement test some students attended lessons including educational presentation completed with a worksheet, other students attended lessons providing the same topic in a way of frontal teaching and without the presentation. The goal of this research was to find out if inquiry-based education affects the level of acquired knowledge and if it leads to its permanent preservation. The results were statistically evaluated and clearly classified into tables and graphs.
399

Porovnání efektivity vybraných metod výuky geologie na ZŠ / Comparison of the effectiveness of selected teaching methods in geology at the primary schools

JOPKOVÁ, Petra January 2016 (has links)
The presented master thesis compares the effectiveness of geology teaching at primary school using a frontal and "alternative" teaching methods. For the research pupils were firstly tested in the form a didactic pre-test, which was focused on the basic knowledge of geology. Then two geological topics were selected and worked out following a frontal and interactive teaching methods (i.e., using Inquiry Based Science Education and multimedia). The topics were alternately taught in two groups (classes) of respondents at the primary schools. The difference in the effectiveness of the selected teaching methods was evaluated on the basis of the results of the post-test. According to the obtained results the teaching of geology at the primary school is definitely more efficient using "alternative" teaching methods in the comparison with frontal methods of teaching.
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Pojmové mapy a jejich využití při výuce fyziky na ZŠ / The Concept Maps and their use in physics teaching in basic schools

NEPOMUCKÁ, Jana January 2017 (has links)
This thesis deals with the possible benefits of using conceptual diagrams in teaching physics at elementary school level. It describes specific methodologies for incorporating conceptual diagrams into the individual phases of the teaching process. The author formulates the benefits and disadvantages of this activating method from the perspective of students as well as teachers. The thesis draws on theoretical knowledge acquired from literature and also from the author´s own pedagogical experience.

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