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2.
J Neurochem ; 167(2): 168-182, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37680022

RÉSUMÉ

Neurodegenerative diseases are a broad heterogeneous group affecting the nervous system. They are characterized, from a pathophysiological perspective, by the selective involvement of a subpopulation of nerve cells with a consequent clinical picture of a disease. Clinical diagnoses of neurodegenerative diseases are quite challenging and often not completely accurate because of their marked heterogeneity and frequently overlapping clinical pictures. Efforts are being made to define sufficiently specific and sensitive markers for individual neurodegenerative diseases or groups of diseases in order to increase the accuracy and speed of clinical diagnosis. Thus said, this present research aimed to identify biomarkers in the cerebrospinal fluid (CSF) and serum (α-synuclein [α-syn], tau protein [t-tau], phosphorylated tau protein [p-tau], ß-amyloid [Aß], clusterin, chromogranin A [chromogrA], cystatin C [cyst C], neurofilament heavy chains [NFH], phosphorylated form of neurofilament heavy chains [pNF-H], and ratio of tau protein/amyloid beta [Ind tau/Aß]) that could help in the differential diagnosis and differentiation of the defined groups of α-synucleinopathies and four-repeat (4R-) tauopathies characterized by tau protein isoforms with four microtubule-binding domains. In this study, we analyzed a cohort of 229 patients divided into four groups: (1) Parkinson's disease (PD) + dementia with Lewy bodies (DLB) (n = 82), (2) multiple system atrophy (MSA) (n = 25), (3) progressive supranuclear palsy (PSP) + corticobasal syndrome (CBS) (n = 30), and (4) healthy controls (HC) (n = 92). We also focused on analyzing the biomarkers in relation to each other with the intention of determining whether they are useful in distinguishing among individual proteinopathies. Our results indicate that the proposed set of biomarkers, when evaluated in CSF, is likely to be useful for the differential diagnosis of MSA versus 4RT. However, these biomarkers do not seem to provide any useful diagnostic information when assessed in blood serum.

3.
Nat Rev Neurol ; 19(10): 599-616, 2023 10.
Article de Anglais | MEDLINE | ID: mdl-37684518

RÉSUMÉ

The term 'endemic parkinsonism' refers to diseases that manifest with a dominant parkinsonian syndrome, which can be typical or atypical, and are present only in a particular geographically defined location or population. Ten phenotypes of endemic parkinsonism are currently known: three in the Western Pacific region; two in the Asian-Oceanic region; one in the Caribbean islands of Guadeloupe and Martinique; and four in Europe. Some of these disease entities seem to be disappearing over time and therefore are probably triggered by unique environmental factors. By contrast, other types persist because they are exclusively genetically determined. Given the geographical clustering and potential overlap in biological and clinical features of these exceptionally interesting diseases, this Review provides a historical reference text and offers current perspectives on each of the 10 phenotypes of endemic parkinsonism. Knowledge obtained from the study of these disease entities supports the hypothesis that both genetic and environmental factors contribute to the development of neurodegenerative diseases, not only in endemic parkinsonism but also in general. At the same time, this understanding suggests useful directions for further research in this area.


Sujet(s)
Syndromes parkinsoniens , Humains , Syndromes parkinsoniens/épidémiologie , Syndromes parkinsoniens/génétique , Guadeloupe/épidémiologie , Europe , Phénotype , Biologie
4.
J Neurol Sci ; 446: 120588, 2023 03 15.
Article de Anglais | MEDLINE | ID: mdl-36827809

RÉSUMÉ

In post-stroke spasticity (PSS), effective treatment with botulinum neurotoxin (BoNT) is associated with transient decrease in activation of the ipsilesional superior parietal lobule (SPL) and intraparietal sulcus (IPS). We hypothesized that this would be reflected in changes in resting-state functional connectivity (rsFC) of the SPL/IPS. Our aim was therefore to assess rsFC of the ipsilesional SPL/IPS in chronic stroke patients with hemiparesis both with and without PSS and to explore the relationship between SPL/IPS rsFC and PSS severity. To this end, fourteen chronic stroke patients with upper limb weakness and PSS (the PSS group) and 8 patients with comparable weakness but no PSS (the control group) underwent clinical evaluation and 3 fMRI examinations, at baseline (W0) and 4 and 11 weeks after BoNT (W4 and W11, respectively). Seed-based rsFC of the atlas-based SPL and IPS was evaluated using a group×time interaction analysis and a correlation analysis with PSS severity (modified Ashworth scale), integrity of the ipsilesional somatosensory afferent pathway (evoked potential N20 latency), and age. In the PSS group, transient improvement in PSS was associated with increase in rsFC between the ipsilesional IPS and the contralesional SPL at W4. The interhemispheric connectivity was negatively correlated with PSS severity at baseline and with PSS improvement at W4. We propose adaptation of the internal forward model as the putative underlying mechanism and discuss its possible association with increased limb use, diminished spastic dystonia, or improved motor performance, as well as its potential contribution to the clinical effects of BoNT.


Sujet(s)
Toxines botuliniques de type A , Agents neuromusculaires , Accident vasculaire cérébral , Humains , Toxines botuliniques de type A/usage thérapeutique , Spasticité musculaire , Agents neuromusculaires/usage thérapeutique , Accident vasculaire cérébral/complications , Lobe pariétal , Imagerie par résonance magnétique
5.
Brain Sci ; 12(12)2022 Dec 03.
Article de Anglais | MEDLINE | ID: mdl-36552120

RÉSUMÉ

The GAITFAST study (gait recovery in patients after acute ischemic stroke) aims to compare the effects of treadmill-based robot-assisted gait training (RTGT) and therapist-assisted treadmill gait training (TTGT) added to conventional physical therapy in first-ever ischemic stroke patients. GAITFAST (Clinicaltrials.gov identifier: NCT04824482) was designed as a single-blind single-center prospective randomized clinical trial with two parallel groups and a primary endpoint of gait speed recovery up to 6 months after ischemic stroke. A total of 120 eligible and enrolled participants will be randomly allocated (1:1) in TTGT or RTGT. All enrolled patients will undergo a 2-week intensive inpatient rehabilitation including TTGT or RTGT followed by four clinical assessments (at the beginning of inpatient rehabilitation 8-15 days after stroke onset, after 2 weeks, and 3 and 6 months after the first assessment). Every clinical assessment will include the assessment of gait speed and walking dependency, fMRI activation measures, neurological and sensorimotor impairments, and gait biomechanics. In a random selection (1:2) of the 120 enrolled patients, multimodal magnetic resonance imaging (MRI) data will be acquired and analyzed. This study will provide insight into the mechanisms behind poststroke gait behavioral changes resulting from intensive rehabilitation including assisted gait training (RTGT or TTGT) in early subacute IS patients.

6.
J Clin Med ; 11(9)2022 Apr 20.
Article de Anglais | MEDLINE | ID: mdl-35566426

RÉSUMÉ

Degenerative spinal cord compression is a frequent pathological condition with increasing prevalence throughout aging. Initial non-myelopathic cervical spinal cord compression (NMDC) might progress over time into potentially irreversible degenerative cervical myelopathy (DCM). While quantitative MRI (qMRI) techniques demonstrated the ability to depict intrinsic tissue properties, longitudinal in-vivo biomarkers to identify NMDC patients who will eventually develop DCM are still missing. Thus, we aim to review the ability of qMRI techniques (such as diffusion MRI, diffusion tensor imaging (DTI), magnetization transfer (MT) imaging, and magnetic resonance spectroscopy (1H-MRS)) to serve as prognostic markers in NMDC. While DTI in NMDC patients consistently detected lower fractional anisotropy and higher mean diffusivity at compressed levels, caused by demyelination and axonal injury, MT and 1H-MRS, along with advanced and tract-specific diffusion MRI, recently revealed microstructural alterations, also rostrally pointing to Wallerian degeneration. Recent studies also disclosed a significant relationship between microstructural damage and functional deficits, as assessed by qMRI and electrophysiology, respectively. Thus, tract-specific qMRI, in combination with electrophysiology, critically extends our understanding of the underlying pathophysiology of degenerative spinal cord compression and may provide predictive markers of DCM development for accurate patient management. However, the prognostic value must be validated in longitudinal studies.

7.
Quant Imaging Med Surg ; 12(4): 2261-2279, 2022 Apr.
Article de Anglais | MEDLINE | ID: mdl-35371944

RÉSUMÉ

Background: Degenerative cervical spinal cord compression is becoming increasingly prevalent, yet the MRI criteria that define compression are vague, and vary between studies. This contribution addresses the detection of compression by means of the Spinal Cord Toolbox (SCT) and assesses the variability of the morphometric parameters extracted with it. Methods: Prospective cross-sectional study. Two types of MRI examination, 3 and 1.5 T, were performed on 66 healthy controls and 118 participants with cervical spinal cord compression. Morphometric parameters from 3T MRI obtained by Spinal Cord Toolbox (cross-sectional area, solidity, compressive ratio, torsion) were combined in multivariate logistic regression models with the outcome (binary dependent variable) being the presence of compression determined by two radiologists. Inter-trial (between 3 and 1.5 T) and inter-rater (three expert raters and SCT) variability of morphometric parameters were assessed in a subset of 35 controls and 30 participants with compression. Results: The logistic model combining compressive ratio, cross-sectional area, solidity, torsion and one binary indicator, whether or not the compression was set at level C6/7, demonstrated outstanding compression detection (area under curve =0.947). The single best cut-off for predicted probability calculated using a multiple regression equation was 0.451, with a sensitivity of 87.3% and a specificity of 90.2%. The inter-trial variability was better in Spinal Cord Toolbox (intraclass correlation coefficient was 0.858 for compressive ratio and 0.735 for cross-sectional area) compared to expert raters (mean coefficient for three expert raters was 0.722 for compressive ratio and 0.486 for cross-sectional area). The analysis of inter-rater variability demonstrated general agreement between SCT and three expert raters, as the correlations between SCT and raters were generally similar to those of the raters between one another. Conclusions: This study demonstrates successful semi-automated compression detection based on four parameters. The inter-trial variability of parameters established through two MRI examinations was conclusively better for Spinal Cord Toolbox compared with that of three experts' manual ratings.

8.
Article de Anglais | MEDLINE | ID: mdl-33883752

RÉSUMÉ

BACKGROUND: In this study we evaluated the impact of location of deep brain stimulation electrode active contact in different parts of the subthalamic nucleus on improvement of non-motor symptoms in patients with Parkinson's disease. METHODS: The subthalamic nucleus was divided into two (dorsolateral/ventromedial) and three (dorsolateral, medial, ventromedial) parts. 37 deep brain stimulation electrodes were divided according to their active contact location. Correlation between change in non-motor symptoms before and one and four months after deep brain stimulation electrode implantation and the location of active contact was made. RESULTS: In dividing the subthalamic nucleus into three parts, no electrode active contact was placed ventromedially, 28 active contacts were located in the medial part and 9 contacts were placed dorsolaterally. After one and four months, no significant difference was found between medial and dorsolateral positions. In the division of the subthalamic nucleus into two parts, 13 contacts were located in the ventromedial part and 24 contacts were placed in the dorsolateral part. After one month, significantly greater improvement in the Non-motor Symptoms Scale for Parkinson's disease (P=0.045) was found on dorsolateral left-sided stimulation, but no significant differences between the ventromedial and dorsolateral positions were found on the right side. CONCLUSION: This study demonstrated the relationship between improvement of non-motor symptoms and the side (hemisphere, left/right) of the deep brain stimulation electrode active contact, rather than its precise location within specific parts of the subthalamic nucleus in patients treated for advanced Parkinson's disease.


Sujet(s)
Stimulation cérébrale profonde , Maladie de Parkinson , Noyau subthalamique , Électrodes , Humains , Maladie de Parkinson/thérapie , Noyau subthalamique/physiologie , Résultat thérapeutique
9.
Front Neurosci ; 15: 742042, 2021.
Article de Anglais | MEDLINE | ID: mdl-34803587

RÉSUMÉ

Corticobasal syndrome (CBS) is clinically characterized by progressive asymmetric rigidity and apraxia together with symptoms suggestive of cortical involvement and basal ganglia dysfunction. The spectrum of neurodegenerative diseases that can manifest with CBS is wide. The associations of CBS with corticobasal degeneration, progressive supranuclear palsy, Alzheimer's disease, frontotemporal lobar degenerations, Creutzfeldt-Jakob disease, or diffuse Lewy body pathology have been reported. We describe the case of a 71-year-old woman with CBS. The histopathological examination of brain tissue revealed concomitant pathology corresponding to the limbic stage of Lewy-related pathology and the intermediate stage of Alzheimer's-type pathology. To date, there have been only a few cases with a similar combination of pathology manifesting with the CBS phenotype that have been described in the literature. The extent and distribution of pathological changes in these cases were somewhat different from ours, and significance for clinical manifestation was attributed to only one of these pathologies. In our case, we assume that both types of pathology contributed to the development of the disease, considering the presumed specific spread of both types of pathological processes according to Braak's staging. Our case expands the spectrum of neurodegenerative pathological processes that may manifest with the typical CBS phenotype. Also, it points out the importance of identifying specific biomarkers that would enable more accurate in vivo differential diagnosis and more accurate determination of the underlying pathological processes of these diseases.

10.
Front Neurosci ; 15: 703620, 2021.
Article de Anglais | MEDLINE | ID: mdl-34658759

RÉSUMÉ

The "Different Hearing" program (DHP) is an educational activity aimed at stimulating musical creativity of children and adults by group composing in the classroom, alternative to the mainstream model of music education in Czechia. Composing in the classroom in the DHP context does not use traditional musical instruments or notation, instead, the participants use their bodies, sounds originating from common objects as well as environmental sounds as the "elements" for music composition by the participants' team, with the teacher initiating and then participating and coordinating the creative process, which ends with writing down a graphical score and then performing the composition in front of an audience. The DHP methodology works with a wide definition of musical composition. We hypothesized that the DHP short-term (2 days) intense workshop would induce changes in subjective appreciation of different classes of music and sound (including typical samples of music composed in the DHP course), as well as plastic changes of the brain systems engaged in creative thinking and music perception, in their response to diverse auditory stimuli. In our study, 22 healthy university students participated in the workshop over 2 days and underwent fMRI examinations before and after the workshop, meanwhile 24 students were also scanned twice as a control group. During fMRI, each subject was listening to musical and non-musical sound samples, indicating their esthetic impression with a button press after each sample. As a result, participants' favorable feelings toward non-musical sound samples were significantly increased only in the active group. fMRI data analyzed using ANOVA with post hoc ROI analysis showed significant group-by-time interaction (opposing trends in the two groups) in the bilateral posterior cingulate cortex/precuneus, which are functional hubs of the default mode network (DMN) and in parts of the executive, motor, and auditory networks. The findings suggest that DHP training modified the behavioral and brain response to diverse sound samples, differentially changing the engagement of functional networks known to be related to creative thinking, namely, increasing DMN activation and decreasing activation of the executive network.

11.
Eur J Neurol ; 28(11): 3784-3797, 2021 11.
Article de Anglais | MEDLINE | ID: mdl-34288268

RÉSUMÉ

BACKGROUND AND PURPOSE: Non-myelopathic degenerative cervical spinal cord compression (NMDC) frequently occurs throughout aging and may progress to potentially irreversible degenerative cervical myelopathy (DCM). Whereas standard clinical magnetic resonance imaging (MRI) and electrophysiological measures assess compression severity and neurological dysfunction, respectively, underlying microstructural deficits still have to be established in NMDC and DCM patients. The study aims to establish tract-specific diffusion MRI markers of electrophysiological deficits to predict the progression of asymptomatic NMDC to symptomatic DCM. METHODS: High-resolution 3 T diffusion MRI was acquired for 103 NMDC and 21 DCM patients compared to 60 healthy controls to reveal diffusion alterations and relationships between tract-specific diffusion metrics and corresponding electrophysiological measures and compression severity. Relationship between the degree of DCM disability, assessed by the modified Japanese Orthopaedic Association scale, and tract-specific microstructural changes in DCM patients was also explored. RESULTS: The study identified diffusion-derived abnormalities in the gray matter, dorsal and lateral tracts congruent with trans-synaptic degeneration and demyelination in chronic degenerative spinal cord compression with more profound alterations in DCM than NMDC. Diffusion metrics were affected in the C3-6 area as well as above the compression level at C3 with more profound rostral deficits in DCM than NMDC. Alterations in lateral motor and dorsal sensory tracts correlated with motor and sensory evoked potentials, respectively, whereas electromyography outcomes corresponded with gray matter microstructure. DCM disability corresponded with microstructure alteration in lateral columns. CONCLUSIONS: Outcomes imply the necessity of high-resolution tract-specific diffusion MRI for monitoring degenerative spinal pathology in longitudinal studies.


Sujet(s)
Syndrome de compression médullaire , Maladies de la moelle épinière , Vertèbres cervicales/imagerie diagnostique , Imagerie par résonance magnétique de diffusion , Humains , Imagerie par résonance magnétique , Moelle spinale/imagerie diagnostique , Syndrome de compression médullaire/imagerie diagnostique
12.
Medicine (Baltimore) ; 100(25): e26356, 2021 Jun 25.
Article de Anglais | MEDLINE | ID: mdl-34160405

RÉSUMÉ

ABSTRACT: In dystonic and spastic movement disorders, abnormalities of motor control and somatosensory processing as well as cortical modulations associated with clinical improvement after botulinum toxin A (BoNT-A) treatment have been reported, but electrophysiological evidence remains controversial. In the present observational study, we aimed to uncover central correlates of post-stroke spasticity (PSS) and BoNT-A-related changes in the sensorimotor cortex by investigating the cortical components of somatosensory evoked potentials (SEPs). Thirty-one chronic stroke patients with PSS of the upper limb were treated with BoNT-A application into the affected muscles and physiotherapy. Clinical and electrophysiological evaluations were performed just before BoNT-A application (W0), then 4 weeks (W4) and 11 weeks (W11) later. PSS was evaluated with the modified Ashworth scale (MAS). Median nerve SEPs were examined in both upper limbs with subsequent statistical analysis of the peak-to-peak amplitudes of precentral P22/N30 and postcentral N20/P23 components. At baseline (W0), postcentral SEPs were significantly lower over the affected cortex. At follow up, cortical SEPs did not show any significant changes attributable to BoNT-A and/or physiotherapy, despite clear clinical improvement. Our results imply that conventional SEPs are of limited value in evaluating cortical changes after BoNT-A treatment and further studies are needed to elucidate its central actions.


Sujet(s)
Toxines botuliniques de type A/administration et posologie , Spasticité musculaire/traitement médicamenteux , Agents neuromusculaires/administration et posologie , Réadaptation après un accident vasculaire cérébral/méthodes , Accident vasculaire cérébral/complications , Adulte , Sujet âgé , Potentiels évoqués somatosensoriels/effets des médicaments et des substances chimiques , Traitement par les exercices physiques/méthodes , Femelle , Études de suivi , Humains , Mâle , Nerf médian/effets des médicaments et des substances chimiques , Nerf médian/physiopathologie , Adulte d'âge moyen , Spasticité musculaire/diagnostic , Spasticité musculaire/étiologie , Spasticité musculaire/physiopathologie , Cortex somatosensoriel/effets des médicaments et des substances chimiques , Cortex somatosensoriel/physiopathologie , Accident vasculaire cérébral/physiopathologie , Résultat thérapeutique , Membre supérieur/innervation , Jeune adulte
13.
Sci Rep ; 11(1): 8322, 2021 04 15.
Article de Anglais | MEDLINE | ID: mdl-33859210

RÉSUMÉ

In cervical dystonia, functional MRI (fMRI) evidence indicates changes in several resting state networks, which revert in part following the botulinum neurotoxin A (BoNT) therapy. Recently, the involvement of the cerebellum in dystonia has gained attention. The aim of our study was to compare connectivity between cerebellar subdivisions and the rest of the brain before and after BoNT treatment. Seventeen patients with cervical dystonia indicated for treatment with BoNT were enrolled (14 female, aged 50.2 ± 8.5 years, range 38-63 years). Clinical and fMRI examinations were carried out before and 4 weeks after BoNT injection. Clinical severity was evaluated using TWSTRS. Functional MRI data were acquired on a 1.5 T scanner during 8 min rest. Seed-based functional connectivity analysis was performed using data extracted from atlas-defined cerebellar areas in both datasets. Clinical scores demonstrated satisfactory BoNT effect. After treatment, connectivity decreased between the vermis lobule VIIIa and the left dorsal mesial frontal cortex. Positive correlations between the connectivity differences and the clinical improvement were detected for the right lobule VI, right crus II, vermis VIIIb and the right lobule IX. Our data provide evidence for modulation of cerebello-cortical connectivity resulting from successful treatment by botulinum neurotoxin.


Sujet(s)
Toxines botuliniques de type A/administration et posologie , Cervelet/physiopathologie , Cognition/physiologie , Repos/physiologie , Torticolis/traitement médicamenteux , Torticolis/physiopathologie , Adulte , Cortex cérébral/physiopathologie , Femelle , Humains , Injections intralésionnelles , Imagerie par résonance magnétique , Mâle , Adulte d'âge moyen , Indice de gravité de la maladie , Torticolis/imagerie diagnostique , Torticolis/psychologie , Résultat thérapeutique
14.
Toxins (Basel) ; 13(2)2021 02 17.
Article de Anglais | MEDLINE | ID: mdl-33671128

RÉSUMÉ

In dystonic and spastic movement disorders, however different in their pathophysiological mechanisms, a similar impairment of sensorimotor control with special emphasis on afferentation is assumed. Peripheral intervention on afferent inputs evokes plastic changes within the central sensorimotor system. Intramuscular application of botulinum toxin type A (BoNT-A) is a standard evidence-based treatment for both conditions. Apart from its peripheral action on muscle spindles, a growing body of evidence suggests that BoNT-A effects could also be mediated by changes at the central level including cerebral cortex. We review recent studies employing electrophysiology and neuroimaging to investigate how intramuscular application of BoNT-A influences cortical reorganization. Based on such data, BoNT-A becomes gradually accepted as a promising tool to correct the maladaptive plastic changes within the sensorimotor cortex. In summary, electrophysiology and especially neuroimaging studies with BoNT-A further our understanding of pathophysiology underlying dystonic and spastic movement disorders and may consequently help develop novel treatment strategies based on neural plasticity.


Sujet(s)
Toxines botuliniques de type A/usage thérapeutique , Cortex cérébral/effets des médicaments et des substances chimiques , Dystonie/traitement médicamenteux , Activité motrice/effets des médicaments et des substances chimiques , Muscles squelettiques/innervation , Agents neuromusculaires/usage thérapeutique , Animaux , Toxines botuliniques de type A/effets indésirables , Cartographie cérébrale , Cortex cérébral/imagerie diagnostique , Cortex cérébral/physiopathologie , Dystonie/diagnostic , Dystonie/physiopathologie , Humains , Imagerie par résonance magnétique , Agents neuromusculaires/effets indésirables , Plasticité neuronale/effets des médicaments et des substances chimiques , Récupération fonctionnelle , Résultat thérapeutique
15.
J Neural Transm (Vienna) ; 128(4): 509-519, 2021 04.
Article de Anglais | MEDLINE | ID: mdl-33591454

RÉSUMÉ

The complex phenomenological understanding of dystonia has transcended from the clinics to genetics, imaging and neurophysiology. One way in which electrophysiology will impact into the clinics are cases wherein a dystonic clinical presentation may not be typical or a "forme fruste" of the disorder. Indeed, the physiological imprints of dystonia are present regardless of its clinical manifestation. Underpinnings in the understanding of dystonia span from the peripheral, segmental and suprasegmental levels to the cortex, and various electrophysiological tests have been applied in the course of time to elucidate the origin of dystonia pathophysiology. While loss of inhibition remains to be the key finding in this regard, intricacies and variabilities exist, thus leading to a notion that perhaps dystonia should best be gleaned as network disorder. Interestingly, the complex process has now spanned towards the understanding in terms of networks related to the cerebellar circuitry and the neuroplasticity. What is evolving towards a better and cohesive view will be neurophysiology attributes combined with structural dynamic imaging. Such a sound approach will significantly lead to better therapeutic modalities in the future.


Sujet(s)
Dystonie , Troubles dystoniques , Cervelet , Cortex cérébral , Humains , Neurophysiologie
16.
Article de Anglais | MEDLINE | ID: mdl-33205755

RÉSUMÉ

Peripheral afferent input is critical for human motor control and motor learning. Both skin and deep muscle mechanoreceptors can affect motor behaviour when stimulated. Whereas some modalities such as vibration have been employed for decades to alter cutaneous and proprioceptive input, both experimentally and therapeutically, the central effects of mechanical pressure stimulation have been studied less frequently. This discrepancy is especially striking when considering the limited knowledge of the neurobiological principles of frequently used physiotherapeutic techniques that utilise peripheral stimulation, such as reflex locomotion therapy. Our review of the available literature pertaining to pressure stimulation focused on transcranial magnetic stimulation (TMS) and neuroimaging studies, including both experimental studies in healthy subjects and clinical trials. Our search revealed a limited number of neuroimaging papers related to peripheral pressure stimulation and no evidence of effects on cortical excitability. In general, the majority of imaging studies agreed on the significant involvement of cortical motor areas during the processing of pressure stimulation. Recent data also point to the specific role of subcortical structures, such as putamen or brainstem reticular formation. A thorough comparison of the published results often demonstrated, however, major inconsistencies which are thought to be due to variable stimulation protocols and statistical power. In conclusion, localised peripheral sustained pressure is a potent stimulus inducing changes in cortical activation within sensory and motor areas. Despite historical evidence for modulation of motor behaviour, no direct link can be established based on available fMRI and electrophysiological data. We highlight the limited amount of research devoted to this stimulus modality, emphasise current knowledge gaps, present recent developments in the field and accentuate evidence awaiting replication or confirmation in future neuroimaging and electrophysiological studies.


Sujet(s)
Troubles neurologiques de la marche/thérapie , Activité motrice/physiologie , Troubles moteurs/thérapie , Techniques de physiothérapie , Pression , Cortex somatosensoriel/physiologie , Stimulation magnétique transcrânienne/méthodes , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Mâle , Adulte d'âge moyen
17.
Sci Rep ; 10(1): 17529, 2020 10 16.
Article de Anglais | MEDLINE | ID: mdl-33067520

RÉSUMÉ

Diffusion magnetic resonance imaging (dMRI) proved promising in patients with non-myelopathic degenerative cervical cord compression (NMDCCC), i.e., without clinically manifested myelopathy. Aim of the study is to present a fast multi-shell HARDI-ZOOMit dMRI protocol and validate its usability to detect microstructural myelopathy in NMDCCC patients. In 7 young healthy volunteers, 13 age-comparable healthy controls, 18 patients with mild NMDCCC and 15 patients with severe NMDCCC, the protocol provided higher signal-to-noise ratio, enhanced visualization of white/gray matter structures in microstructural maps, improved dMRI metric reproducibility, preserved sensitivity (SE = 87.88%) and increased specificity (SP = 92.31%) of control-patient group differences when compared to DTI-RESOLVE protocol (SE = 87.88%, SP = 76.92%). Of the 56 tested microstructural parameters, HARDI-ZOOMit yielded significant patient-control differences in 19 parameters, whereas in DTI-RESOLVE data, differences were observed in 10 parameters, with mostly lower robustness. Novel marker the white-gray matter diffusivity gradient demonstrated the highest separation. HARDI-ZOOMit protocol detected larger number of crossing fibers (5-15% of voxels) with physiologically plausible orientations than DTI-RESOLVE protocol (0-8% of voxels). Crossings were detected in areas of dorsal horns and anterior white commissure. HARDI-ZOOMit protocol proved to be a sensitive and practical tool for clinical quantitative spinal cord imaging.


Sujet(s)
Imagerie par résonance magnétique de diffusion , Syndrome de compression médullaire/anatomopathologie , Maladies de la moelle épinière/anatomopathologie , Adulte , Génie biomédical , Études cas-témoins , Vertèbres cervicales/anatomopathologie , Analyse de regroupements , Imagerie par tenseur de diffusion , Femelle , Humains , Mâle , Adulte d'âge moyen , Reproductibilité des résultats , Sensibilité et spécificité , Rapport signal-bruit , Syndrome de compression médullaire/imagerie diagnostique , Maladies de la moelle épinière/imagerie diagnostique
18.
Sci Rep ; 10(1): 1436, 2020 01 29.
Article de Anglais | MEDLINE | ID: mdl-31996749

RÉSUMÉ

The link between dystonia and tremor has been known for decades, but the question of whether they are two separate illnesses or just different manifestations of one disease with the same pathophysiological background remains unanswered. We distinguish two types of tremor in dystonia: dystonic tremor (DT), which appears on the body part affected by dystonia, and tremor associated with dystonia (TAWD), which appears in locations where the dystonia does not occur. In this study, the frequency of occurrence of different forms of tremor was determined by clinical examination in a group of adult-onset isolated cervical dystonia (CD) patients treated with regular local injections of botulinum toxin A in our department. In total, 120 patients were included in the study, of which 70 (58.3%) had DT of the head. TAWD was, in all 14 cases (11.7%), observed on the upper limbs, in the form of static or intentional tremor. The aim of this study was to point out the presence of TAWD as one of the clinical signs of CD. DT occurred in more than half of the patients and appears to be a relatively common part of the clinical picture in patients with CD.


Sujet(s)
Dystonie/épidémiologie , Torticolis/épidémiologie , Tremblement/épidémiologie , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , République tchèque/épidémiologie , Femelle , Humains , Mâle , Adulte d'âge moyen , Prévalence
19.
Front Neurosci ; 13: 722, 2019.
Article de Anglais | MEDLINE | ID: mdl-31379481

RÉSUMÉ

Sustained pressure stimulation of the body surface has been used in several physiotherapeutic techniques, such as reflex locomotion therapy. Clinical observations of global motor responses and subsequent motor behavioral changes after stimulation in certain sites suggest modulation of central sensorimotor control, however, the neuroanatomical correlates remain undescribed. We hypothesized that different body sites would specifically influence the sensorimotor system during the stimulation. We tested the hypothesis using functional magnetic resonance imaging (fMRI) in thirty healthy volunteers (mean age 24.2) scanned twice during intermittent manual pressure stimulation, once at the right lateral heel according to reflex locomotion therapy, and once at the right lateral ankle (control site). A flexible modeling approach with finite impulse response basis functions was employed since non-canonical hemodynamic response was expected. Subsequently, a clustering algorithm was used to separate areas with differential timecourses. Stimulation at both sites induced responses throughout the sensorimotor system that could be mostly separated into two anti-correlated subsystems with transient positive or negative signal change and rapid adaptation, although in heel stimulation, insulo-opercular cortices and pons showed sustained activation. In direct voxel-wise comparison, heel stimulation was associated with significantly higher activation levels in the contralateral primary motor cortex and decreased activation in the posterior parietal cortex. Thus, we demonstrate that the manual pressure stimulation affects multiple brain structures involved in motor control and the choice of stimulation site impacts the shape and amplitude of the blood oxygenation level-dependent response. We further discuss the relationship between the affected structures and behavioral changes after reflex locomotion therapy.

20.
Water Sci Technol ; 79(12): 2407-2416, 2019 Jun.
Article de Anglais | MEDLINE | ID: mdl-31411595

RÉSUMÉ

Urban hydrology was created in order to improve methods of managing the runoff of precipitation in towns and protect them from flooding while also protecting public health and environment. The essence of a future solution consists in finding an acceptable compromise of an alternative solution for draining rainwater from a territory. The content of this work is a study focused on resolving the percolation of water from surface runoff and the confrontation between a field test, laboratory analysis, and numerical analysis. By confronting and subsequently proposing conditions for percolation, documents will be created for making urban drainage better and more efficient. The reason for the origin of the subject work follows from the insufficient information on infiltration systems in Slovak technical standards and, likewise, the lack of support for the percolation of water from surface runoff. This work points out the approaches, principles, and fundamentals of a proposal for percolation. The aim of the work is distribution of scientific knowledge in the field of research and solutions for the percolation of water from surface runoff, with emphasis placed on the retention capacity of the selected territory and the intensity of precipitation. A geological study (orientational, detailed or supplementary) must always be conducted with any decision on rainwater percolation in a certain locality. Its range is dependent on the difficulty and type of construction. The preliminary study of areal condition should be focused on detailed engineering-geological and hydrological information. After this work, it is concluded that the percolation of rainwater in urban areas with suitable hydrogeological condition is an effective rainwater management technology as well as protection to congestion of sewer systems.


Sujet(s)
Pluie , Villes , Hydrologie , Élimination des déchets liquides , Mouvements de l'eau
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