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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.
31

Spinal cord injury: assessment of autonomic state-dependent control of cardiovascular system and body core temperature

Guaraldi, Pietro <1979> 24 May 2012 (has links)
Spinal cord injury (SCI) results not only in paralysis; but it is also associated with a range of autonomic dysregulation that can interfere with cardiovascular, bladder, bowel, temperature, and sexual function. The entity of the autonomic dysfunction is related to the level and severity of injury to descending autonomic (sympathetic) pathways. For many years there was limited awareness of these issues and the attention given to them by the scientific and medical community was scarce. Yet, even if a new system to document the impact of SCI on autonomic function has recently been proposed, the current standard of assessment of SCI (American Spinal Injury Association (ASIA) examination) evaluates motor and sensory pathways, but not severity of injury to autonomic pathways. Beside the severe impact on quality of life, autonomic dysfunction in persons with SCI is associated with increased risk of cardiovascular disease and mortality. Therefore, obtaining information regarding autonomic function in persons with SCI is pivotal and clinical examinations and laboratory evaluations to detect the presence of autonomic dysfunction and quantitate its severity are mandatory. Furthermore, previous studies demonstrated that there is an intimate relationship between the autonomic nervous system and sleep from anatomical, physiological, and neurochemical points of view. Although, even if previous epidemiological studies demonstrated that sleep problems are common in spinal cord injury (SCI), so far only limited polysomnographic (PSG) data are available. Finally, until now, circadian and state dependent autonomic regulation of blood pressure (BP), heart rate (HR) and body core temperature (BcT) were never assessed in SCI patients. Aim of the current study was to establish the association between the autonomic control of the cardiovascular function and thermoregulation, sleep parameters and increased cardiovascular risk in SCI patients.
32

Melanopsin Retinal Ganglion Cells: relevance to circadian rhythms and sleep in neurodegeneration

La Morgia, Chiara <1977> 24 May 2012 (has links)
In this PhD thesis 3 projects were addressed focusing on the melanopsin retinal ganglion cells (mRGCs) system and its relevance for circadian rhythms and sleep in neurodegeneration. The first project was aimed at completing the characterization of mRGCs system in hereditary optic neuropathies (LHON and DOA). We confirmed that mRGCs are relatively spared also in post-mortem retinal specimens of a DOA case and pupillometric evaluation of LHON patients showed preservation of the pupillary light reflex, with attenuated responses compared to controls. Cell studies failed to indicate a protective role exerted by melanopsin itself. The second project was aimed at characterizing the possible occurrence of optic neuropathy and rest-activity circadian rhythm dysfunction in Alzheimer (AD) and Parkinson disease (PD), as well as, at histological level, the possible involvement of mRGCs in AD. OCT studies demonstrated a subclinical optic neuropathy in both AD and PD patients, with a different pattern involving the superior and nasal quadrants in AD and the temporal quadrant in PD. Actigraphic studies demonstrated a tendency towards an increased intradaily variability (IV) and reduced relative amplitude (RA) of rest-activity circadian rhythm in AD and a significant increased IV a reduced RA in PD. Immunohistochemical analysis of post-mortem retinal specimens and optic nerve cross-sections of neuropathologically confirmed AD cases demonstrated a significant loss of mRGCs and a nearly significant loss of axons in AD compared to controls. The mRGCs were affected in AD independently from age and magnitude of axonal loss. Overall these results suggest a role of the mRGCs system in the pathogenesis of circadian dysfunction in AD. The third project was aimed at evaluating the possible association between a single nucleotide polymorphism of the OPN4 gene and chronotype or SAD, failing to find any significant association with chronotype, but showing a non-significant increment of TT genotype in SAD.
33

Studio di popolazione sull'associazione tra sindrome delle gambe senza riposo ed emicrania / Population-based study on the association between Restless Legs Syndrome and migraine

Zanigni, Stefano <1979> 11 June 2013 (has links)
Introduzione: La sindrome delle gambe senza riposo (RLS) è un disturbo caratterizzato da sensazione spiacevole disestesica generalmente agli arti inferiori, che si presenta o peggiora nelle ore serali-notturne e che migliora con il movimento. Studi clinici hanno mostrato una maggiore prevalenza di RLS negli emicranici, mentre mancano studi condotti su popolazione generale non selezionata. Lo scopo di questo studio era quello di valutare la associazione tra emicrania e RLS in una popolazione italiana adulta. Inoltre è stata valutata l’associazione tra RLS e cefalea fenotipizzata attraverso metodica di principal components analysis (PCA). Materiali e metodi: la presenza di RLS e di emicrania è stata determinata attraverso questionari basati sui criteri diagnostici correnti in un campione di 1567 partecipanti di un fase preliminare di uno studio in corso sulla popolazione adulta della Val Venosta (BZ). Risultati: gli emicranici hanno presentato un significativo maggior rischio di soffrire di RLS rispetto ai non emicranici, anche dopo aggiustamento per fattori confondenti come età, sesso, depressione, ansia e qualità del sonno (p = 0.049). Questa associazione non era modificata dalla presenza di aura emicranica, di cause possibili di RLS secondaria e dalla frequenza di attacchi emicranici. Inoltre la RLS non era risultata significativamente associata alla cefalea di tipo tensivo (TTH). Dall’analisi di associazione tra RLS e cefalea fenotipizzata attraverso PCA era emerso che la componente 1, caratterizzata da sintomi di sensitivizzazione del sistema nervoso centrale (SNC), correlava significativamente con la presenza di RLS (p = 0.021). Conclusioni: RLS ed emicrania sono risultate associate nel nostro campione di popolazione adulta; inoltre la RLS ha mostrato una correlazione significativa con i sintomi di sensitivizzazione del SNC legati agli attacchi di cefalea. Questa associazione potrebbe risiedere in una possibile base patogenetica comune. / Backgrounds: Restless legs syndrome (RLS) is a disorder characterized by an uncomfortable sensation usually in the legs, which appears or worsens at evening-night and improves with movement. Clinical studies showed a higher prevalence of RLS in migraineurs compared to non-migraineurs but studies conducted on an unselected general population are lacking. The aim of this study was to evaluate the association between migraine and RLS in an Italian adult population. Moreover, we assessed the relationship between RLS and headache characterized through principal components analysis (PCA). Materials and methods: the presence of migraine and RLS was assessed via questionnaires according to current diagnostic criteria in 1567 participants of a preliminary phase of an ongoing adult population-based study conducted in Val Venosta. Results: migraineurs showed a significant increased risk of suffering from RLS compared to non-migraineurs also after adjustment for confounding factors such as age, sex, depression, anxiety and sleep quality (p = 0.049). This association was not altered by aura status, potential causes of secondary RLS and migraine frequency. RLS was not significantly related with tension type headache (TTH). The analysis of the association between RLS and headache assessed through PCA showed that component 1, characterized by central nervous system (CNS) sensitization symptoms, correlated significantly with RLS (p = 0.021). Conclusions: RLS and migraine were associated in our adult population sample; moreover RLS showed a significant association with headache-related CNS sensitization symptoms. This association could be explained by a possible shared pathogenic pathway.
34

Longitudinal evolution of cognitive functions in patients with multiple system atrophy: a prospective study

Stanzani Maserati, Michelangelo <1975> 11 June 2013 (has links)
Introduction and Background: Multiple system atrophy (MSA) is a sporadic, adult-onset, progressive neurodegenerative disease characterized clinically by parkinsonism, cerebellar ataxia, and autonomic failure. We investigated cognitive functions longitudinally in a group of probable MSA patients, matching data with sleep parameters. Patients and Methods: 10 patients (7m/3f) underwent a detailed interview, a general and neurological examination, laboratory exams, MRI scans, a cardiovascular reflexes study, a battery of neuropsychological tests, and video-polysomnographic recording (VPSG). Patients were revaluated (T1) a mean of 16±5 (range: 12-28) months after the initial evaluation (T0). At T1, the neuropsychological assessment and VPSG were repeated. Results: The mean patient age was 57.8±6.4 years (range: 47-64) with a mean age at disease onset of 53.2±7.1 years (range: 43-61) and symptoms duration at T0 of 60±48 months (range: 12-144). At T0, 7 patients showed no cognitive deficits while 3 patients showed isolated cognitive deficits. At T1, 1 patient worsened developing multiple cognitive deficits from a normal condition. At T0 and T1, sleep efficiency was reduced, REM latency increased, NREM sleep stages 1-2 slightly increased. Comparisons between T1 and T0 showed a significant worsening in two tests of attention and no significant differences of VPSG parameters. No correlation was found between neuropsychological results and VPSG findings or RBD duration. Discussion and Conclusions: The majority of our patients do not show any cognitive deficits at T0 and T1, while isolated cognitive deficits are present in the remaining patients. Attention is the cognitive function which significantly worsened. Our data confirm the previous findings concerning the prevalence, type and the evolution of cognitive deficits in MSA. Regarding the developing of a condition of dementia, our data did not show a clear-cut diagnosis of dementia. We confirm a mild alteration of sleep structure. RBD duration does not correlate with neuropsychological findings.
35

Psychiatric comorbidity, Restless Legs Syndrome and Nocturnal Eating Disorder: a case-control study

Marconi, Sara <1979> 11 June 2013 (has links)
Objective: to evaluate the psychopathological profile in primary Restless Legs Syndrome (p-RLS) patients with and without nocturnal eating disorder (NED), analysing obsessive-compulsive traits, mood and anxiety disorder, and the two domains of personality proposed by Cloninger, temperament and character. Methods: we tested ten p-RLS patients without NED, ten p-RLS patients with NED and ten healthy control subjects, age and sex-matched, using Hamilton Depression and Anxiety Rating Scales, State-Trait Anxiety Inventory, Maudsley Obsessive Compulsive Inventory (MOCI) and Temperament and Character Inventory - revised (TCI). Results: p-RLS patients, particularly those with NED, had increased anxiety factor scores. MOCI-total, doubting and checking compulsion, and TCI-harm avoidance scores were significantly higher in p-RLS patients with NED. p-RLS patients without NED had significantly higher MOCI-doubting scores and a trend toward higher checking compulsion and harm avoidance scores with an apparent grading from controls to p-RLS patients without NED to p-RLS with NED. Conclusions: higher harm avoidance might predispose to display obsessive-compulsive symptoms, RLS and then, with increasing severity, compulsive nocturnal eating. RLS and NED could represent a pathological continuum in which a dysfunction in the limbic system, possibly driven by a dopaminergic dysfunction, could be the underlying pathophysiological mechanism.
36

Resa diagnostica di anamnesi, EEG intercritico ed home-made video negli episodi parossistici notturni: confronto con la VEPSG / Clinical history , interictal EEG and home-made video diagnostic accuracy: comparison with the VEPSG

Broli, Marcella <1977> 11 June 2013 (has links)
Poiché la diagnosi differenziale degli episodi parossistici notturni è affidata alla VEPSG, tenendo conto dei limiti di tale metodica, il progetto attuale ha lo scopo di definire la resa diagnostica di strumenti alternativi alla VEPSG: anamnesi, home-made video ed EEG intercritico. Sono stati reclutati consecutivamente 13 pazienti, afferiti al nostro Dipartimento per episodi parossistici notturni. Ciascun paziente è stato sottoposto ad un protocollo diagnostico standardizzato. A 5 Medici Esperti in Epilessia e Medicina del Sonno è stato chiesto di formulare un orientamento diagnostico sulla base di anamnesi, EEG intercritico, home-made video e VEPSG. Attraverso l’elaborazione degli orientamenti diagnostici è stata calcolata la resa diagnostica delle procedure esaminate, a confronto con la VEPSG, attraverso il concetto di “accuratezza diagnostica”. Per 6 pazienti è stato possibile porre una diagnosi di Epilessia Frontale Notturna, per 2 di parasonnia, in 5 la diagnosi è rimasta dubbia. L’accuratezza diagnostica di ciascuna procedura è risultata moderata, con lievi differenze tra le diverse procedure (61.5% anamnesi; 66% home-made video; 69,2 % EEG intercritico). E’ essenziale migliorare ulteriormente l’accuratezza diagnostica di anamnesi, EEG intercritico ed home-made video, che possono risultare cruciali nei casi in cui la diagnosi non è certa o quando la VEPSG non è disponibile. / Nocturnal frontal lobe epilepsy (NFLE) seizures appear almost exclusively during sleep. The differential diagnosis between this condition and sleep-related non-epileptic paroxysmal motor phenomena, in particular parasomnias, is arduous. Moreover, accepted criteria for the diagnosis of NFLE are lacking. At present video-polysomnographic recording of the seizures during sleep is the gold standard for the diagnosis but this technique is expensive and not available everywhere. The aim of this study is to measure the diagnostic accuracy of clinical history, interictal EEG and home-made video in distinguishing NFLE from non-epileptic paroxysmal sleep disorders. 13 patients who presented paroxysmal motor phenomena during sleep were consecutively enrolled in our Department and a specific diagnostic examination battery was performed. After the completion of the examinations the results were analyzed by five experts in clinical sleep medicine and epilepsy and a diagnostic decision was made: 6 subjects were classified as NFLE, 2 as parasomnias and 5 as “uncertain” diagnosis. From experts diagnostic decision, the clinical history, interictal EEG and home-made video diagnostic accuracy were calculated. The diagnostic accuracy was overall moderate and showed only slight differences between the procedures. However, it is essential to improve the diagnostic accuracy of clinical history, interictal EEG and home-made video recording that could be helpful in cases difficult to diagnose or when VEPSG monitoring is not available. In addition, future research should define reliable clinical and VEPSG criteria for the diagnosis of nocturnal frontal lobe seizures.
37

Studio neuroradiologico (morfologico e funzionale) nei pazienti con Epilessia Frontale Notturna / Neuroradiological study (morphological and functional) in patients with Nocturnal Frontal Lobe Epilepsy

Naldi, Ilaria <1977> 11 June 2013 (has links)
L'epilessia frontale notturna (EFN) è caratterizzata da crisi motorie che insorgono durante il sonno. Scopo del progetto è studiare le cause fisiopatologiche e morfo-funzionali che sottendono ai fenomeni motori nei pazienti con EFN e identificare alterazioni strutturali e/o metaboliche mediante tecniche avanzate di Risonanza Magnetica (RM). Abbiamo raccolto una casistica di pazienti con EFN afferenti al Centro Epilessia e dei Disturbi del Sonno del Dipartimento di Scienze Neurologiche, Università di Bologna. Ad ogni paziente è stato associato un controllo sano di età (± 5 anni) e sesso corrispondente. Tutti sono stati studiati mediante tecniche avanzate di RM comprendenti Spettroscopia del protone (1H-MRS), Tensore di diffusione ed imaging 3D ad alta risoluzione per analisi morfometriche. In particolare, la 1H-MRS è stata effettuata su due volumi di interesse localizzati nei talami e nel giro del cingolo anteriore. Sono stati inclusi nell’analisi finale 19 pazienti (7 M), età media 34 anni (range 19-50) e 14 controlli (6 M) età media 30 anni (range 19-40). A livello del cingolo anteriore il rapporto della concentrazione di N-Acetil-Aspartato rispetto alla Creatina (NAA/Cr) è risultato significativamente ridotto nei pazienti rispetto ai controlli (p=0,021). Relativamente all’analisi di correlazione, l'analisi tramite modelli di regressione multipla ha evidenziato che il rapporto NAA/Cr nel cingolo anteriore nei pazienti correlava con la frequenza delle crisi (p=0,048), essendo minore nei pazienti con crisi plurisettimanali/plurigiornaliere. Per interpretare il dato ottenuto è possibile solo fare delle ipotesi. L’NAA è un marker di integrità, densità e funzionalità neuronale. E’ possibile che alla base della EFN ci siano alterazioni metaboliche tessutali in precise strutture come il giro del cingolo anteriore. Questo apre nuove possibilità sull’utilizzo di strumenti di indagine basati sull’analisi di biosegnali, per caratterizzare aree coinvolte nella genesi della EFN ancora largamente sconosciute e chiarire ulteriormente l’eziologia di questo tipo di epilessia. / Nocturnal frontal lobe epilepsy (NFLE) is characterized by motor seizuresoccurring during sleep. Aims of the study were to identify the pathophysiological and anatomo-functional factors implicated in the genesis of the motor episodes and possible structural alterations and/or metabolic disorders ,in NFLE patients using advanced techniques of Magnetic Resonance (MR). We have collected a series of patients with NFLE attending the Epilepsy and Sleep Centres of the Department of Neurological Sciences, Bologna University. For each NFLE patient, one control subject of the same sex and age (±5 years) was recruited. All subjects were studied using proton spectroscopy (1H-MRS), diffusion tensor imaging and high resolution 3D-imaging for morphometric analyses. In particular, 1H-MRS was performed in two regions of interest: the thalami and the anterior cingulate gyrus. Nineteen patients (7M), mean age 34 years (range 19-50) and 14 controls (6 M), mean age 30 years (range 19-40), were included in the final analysis. At the level of the anterior cingulate the ratio of the concentration of N-Acetyl-Aspartate compared to Creatine (NAA/Cr) was significantly reduced in patients compared with controls (p=0,021). A multiple regression analysis was performed, showing that the NAA/Cr ratio in the anterior cingulate in patients correlated with the seizures frequency (p=0,048), being lower in patients with very frequent seizures. As NAA is a marker of integrity, density and neuronal function, we speculate that metabolic changes in specific structures, such as the anterior cingulate, may underlie the pathogenesis of NFLE. Our results open up new possibilities for the use of methodologies of biomedical signal/image processing to characterize the areas involved in the genesis of NFLE, which are currently largely unknown and to further clarify the etiology of this type of epilepsy.
38

Sleep motor activity in parkinsonian syndromes at onset: a prospective study to determine potential diagnostic and prognostic markers

Alessandria, Maria <1979> 12 May 2014 (has links)
Aim of this study is to describe the possible diagnostic value of sleep disturbances in the differential diagnosis of neurodegenerative diseases characterized by parkinsonism at onset. 42 consecutive patients with parkinsonian features and disease duration up to 3 years were included in the BO-ProPark study. Each patient was evaluated twice, at baseline (T0) and 16 months later (T1). Patients were diagnosed as Parkinson disease (PD, 27 patients), PD plus (PD with cognitive impairment/dementia or dysautonomia, 4 patients) and parkinsonian syndrome (PS, 11 patients). All patients underwent a full night video-polysomnography scored by a neurologist blinded to the clinical diagnosis. Sleep efficiency and total sleep time were reduced in all patients; wake after sleep onset was higher in patients with atypical parkinsonisms than in PD patients. No significant differences between groups of patients were detected in other sleep parameters. The mean percentage of epochs with enhanced tonic muscle EMG activity during REM sleep was higher in PD plus and PS than in PD. No difference in phasic muscle EMG activity during REM sleep was seen between the two groups. REM behaviour disorder was more frequent in PD plus and PS than in PD patients. Our data suggest that REM sleep motor control is more frequently impaired at disease onset in patients with PS and PD plus compared to PD patients. The presence of RBD or an enhanced tonic muscle EMG activity in a patient with recent onset parkinsonian features should suggest a diagnosis of atypical parkinsonism, rather than PD. More data are needed to establish the diagnostic value of these features in the differential diagnosis of parkinsonisms. The evaluation of sleep disorders may be a useful tool in the differential diagnosis of parkinsonism at onset.
39

Aportación técnica al estudio electromiográfico de la unidad motora

Valls Solé, Josep 01 January 1985 (has links)
Se efectúa una revisión del estado actual de los conocimientos electrofisiológicos sobre la unidad motora.Se propone una técnica electromiográfica de detección y registro de potenciales de acción con metodología propia creada a partir de bases extraídas de la electromiografía clásica y de la electromiografía de fibra única.Se aplica dicha técnica al estudio de la unidad motora en sujetos sanos y pacientes afectos de enfermedades neuromusculares de larga evolución previamente diagnosticadas.Se analizan los resultados estadísticamente y se extraen los valores de referencia.Se discuten los resultados y se concluye refiriendo principalmente el rendimiento diagnostico de la técnica.
40

Evidências clinicas para o modelo de neuroprogressão no transtorno bipolar

Goi, Pedro Domingues January 2014 (has links)
O Transtorno Bipolar (TB) é uma patologia prevalente, grave, crônica, e que apresenta um curso longitudinal muito pior que se imaginava décadas atrás. Além da alternância entre períodos de depressão, mania e eutimia, a recorrência e a progressão do TB conferem gravidade e frequência crescentes aos episódios. A neuroprogressão foi um termo cunhado para definir a aceleração do processo de doença e seus fatores subjacentes, como alterações de biomarcadores periféricos, funções cognitivas, neuroimagem e funcionalidade, que emergem em graus variáveis dependendo da fase de evolução. Todas estas evidências justificaram a classificação do TB em estágios clínicos teóricos distintos, que ainda carecem de validação empírica. Um dos mais recentes deles propõe 1 estágio latente e 4 estágios clínicos distintos (Kapczinski et al, 2009) (1). O presente trabalho avaliou, portanto, as diferentes estratégias farmacológicas para a manutenção da eutimia em uma amostra de pacientes com TB em diferentes estágios (artigo 1), e a associação do atraso no tratamento do primeiro episódio com fatores de pior prognóstico e com os estágios do TB (artigo 2). Em conjunto, os resultados mostraram que a abordagem farmacológica instituída pelo psiquiatra clínico, necessária para manter o paciente em eutimia, é diferente conforme a classificação em estágios. O número de fármacos prescrito também está relacionado ao declínio da funcionalidade. Além disso, o atraso no início do tratamento do TB é diretamente proporcional ao estágio de evolução da doença, e está relacionado a fatores de pior prognóstico, como o número de episódios. Os achados fornecem evidência para modificar certas intervenções no TB: a primeira, que diretrizes de tratamento poderiam considerar os estágios, visando um tratamento mais personalizado para guiar a eficácia do tratamento; e por último, que o esforço em diagnosticar e tratar o TB com precisão e rapidez pode ser uma das medidas para frear a neuroprogressão. / Bipolar Disorder (TB) is a severe, prevalent, and chronic disease, that exhibits worse longitudinal course than previously thought. Beyond the switching phases of depression, mania and euthymia, recurrence and progression of TB increases severity and frequency of episodes. The neuroprogression was a term created to define the acceleration of the disease and its underlying factors, such as changes in peripheral biomarkers, in cognitive performance, in neuroimaging and functioning, that emerge in different degrees depending on the stage of evolution. All those evidences justify the classification of TB in different clinical stages, which still lack empirical validation. One of most recently proposed staging model describes 1 latent stage and 4 clinical stages (Kapczinski et al, 2009) (1). The present study therefore evaluated the different pharmacological strategies for the maintenance of euthymia in a sample of TB patients at different stages (Article 1), and the association of first-episode tretament delay with poor prognosis and BD stages (Article 2). Together, the results showed that maintenance pharmacological treatment in a naturallistic setting is different according to the staging classification. The number of drugs prescribed is also associated to functioning. Moreover, the treatment delay is positively correlated to the stage of the disease, and is related to poor outcomes (i.e. number of episodes). The findings provide evidence to modify certain interventions in TB: first, that treatment guidelines might consider staging to provide tailored approaches and to guide treatment efficacy; and secondly, that the effort to accurately diagnose and treat TB can be one of the measures to restrain neuroprogression.

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