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1.
Int J Mol Sci ; 24(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37047273

RESUMO

Several reports have pointed out that Chitinases are expressed and secreted by various cell types of central nervous system (CNS), including activated microglia and astrocytes. These cells play a key role in neuroinflammation and in the pathogenesis of many neurodegenerative disorders. Increased levels of Chitinases, in particular Chitotriosidase (CHIT-1) and chitinase-3-like protein 1 (CHI3L1), have been found increased in several neurodegenerative disorders. Although having important biological roles in inflammation, to date, the molecular mechanisms of Chitinase involvement in the pathogenesis of neurodegenerative disorders is not well-elucidated. Several studies showed that some Chitinases could be assumed as markers for diagnosis, prognosis, activity, and severity of a disease and therefore can be helpful in the choice of treatment. However, some studies showed controversial results. This review will discuss the potential of Chitinases in the pathogenesis of some neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and multiple sclerosis, to understand their role as distinctive biomarkers of neuronal cell activity during neuroinflammatory processes. Knowledge of the role of Chitinases in neuronal cell activation could allow for the development of new methodologies for downregulating neuroinflammation and consequently for diminishing negative neurological disease outcomes.


Assuntos
Quitinases , Esclerose Múltipla , Doenças Neurodegenerativas , Humanos , Quitinases/genética , Doenças Neuroinflamatórias , Biomarcadores
2.
Sensors (Basel) ; 22(13)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35808494

RESUMO

Studies on gait symmetry in healthy population have mainly been focused on small range of age categories, neglecting Teenagers (13-18 years old) and Middle-Aged persons (51-60 years old). Moreover, age-related effects on gait symmetry were found only when the symmetry evaluation was based on whole-body acceleration than on spatiotemporal parameters of the gait cycle. Here, we provide a more comprehensive analysis of this issue, using a Symmetry Index (SI) based on whole-body acceleration recorded on individuals aged 6 to 84 years old. Participants wore a single inertial sensor placed on the lower back and walked for 10 m at comfortable, slow and fast speeds. The SI was computed using the coefficient of correlation of whole-body acceleration measured at right and left gait cycles. Young Adults (19-35 years old) and Adults (36-50 years old) showed stable SI over the three speed conditions, while Children (6-12 years old), Teenagers (13-18 years old), Middle-Aged persons and Elderly (61-70 and 71-84 years old) exhibited lower SI values when walking at fast speed. Overall, this study confirms that whole-body gait symmetry is lower in Children and in Elderly persons over 60 years of age, showing, for the first time, that asymmetries appear also during teenage period and in Middle-Aged persons (51-60 years old).


Assuntos
Marcha , Velocidade de Caminhada , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Marcha/fisiologia , Humanos , Pessoa de Meia-Idade , Velocidade de Caminhada/fisiologia , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
3.
Eur J Appl Physiol ; 121(2): 465-478, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33106932

RESUMO

PURPOSE: An age-related decline in anticipatory postural mechanisms has been reported during gait initiation; however, it is unclear whether such decline may jeopardize whole-body stability following unexpected balance perturbations. This study aimed to compare young and older individuals' ability to generate postural responses and preserve stability in response to external waist perturbations delivered within gait initiation. METHODS: Ten young and ten older participants performed 10 gait initiation trials followed by 48 unperturbed and 12 perturbed trials in a random order. A stereophotogrammetric system and three force platforms were used to quantify mechanical parameters from the preparatory phase (e.g., timing and amplitude of postural adjustments) and from the stepping phase (e.g., step characteristics and dynamic stability). Activation patterns of lower leg muscles were determined by surface electromyography. RESULTS: Older participants responded to perturbation with lower increase in both magnitude (p < 0.001; η2p = 0.62) and duration (p = 0.001; η2p = 0.39) of preparatory parameters and soleus muscle activity (p < 0.001; η2p = 0.55), causing shorter (p < 0.001; η2p = 0.59) and lower (p < 0.001; η2p = 0.43) stepping, compared to young participants. Interestingly, young participants showed greater correlations between preparatory phase parameters and dynamic stability of the first step than older participants (average r of - 0.40 and - 0.06, respectively). CONCLUSION: The results suggest that young participants took more time than older to adjust the anticipatory biomechanical response to perturbation attempting to preserve balance during stepping. In contrast, older adults were unable to modify their anticipatory adjustments in response to perturbation and mainly relied on compensatory mechanisms attempting to preserve stability via a more cautious stepping strategy.


Assuntos
Marcha/fisiologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Acidentes por Quedas/prevenção & controle , Adaptação Fisiológica/fisiologia , Adulto , Idoso , Envelhecimento/fisiologia , Fenômenos Biomecânicos/fisiologia , Cognição/fisiologia , Eletromiografia/métodos , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Músculo Esquelético/fisiologia
4.
Sensors (Basel) ; 22(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35009638

RESUMO

The Timed Up and Go (TUG) test quantifies physical mobility by measuring the total performance time. In this study, we quantified the single TUG subcomponents and, for the first time, explored the effects of gait cycle and pelvis asymmetries on them. Transfemoral (TF) and transtibial (TT) amputees were compared with a control group. A single wearable inertial sensor, applied to the back, captured kinematic data from the body and pelvis during the 10-m walk test and the TUG test. From these data, two categories of symmetry indexes (SI) were computed: One SI captured the differences between the antero-posterior accelerations of the two sides during the gait cycle, while another set of SI quantified the symmetry over the three-dimensional pelvis motions. Moreover, the total time of the TUG test, the time of each subcomponent, and the velocity of the turning subcomponents were measured. Only the TF amputees showed significant reductions in each SI category when compared to the controls. During the TUG test, the TF group showed a longer duration and velocity reduction mainly over the turning subtasks. However, for all the amputees there were significant correlations between the level of asymmetries and the velocity during the turning tasks. Overall, gait cycle and pelvis asymmetries had a specific detrimental effect on the turning performance instead of on linear walking.


Assuntos
Amputados , Membros Artificiais , Dispositivos Eletrônicos Vestíveis , Amputação Cirúrgica , Fenômenos Biomecânicos , Marcha , Humanos , Extremidade Inferior , Pelve , Equilíbrio Postural , Estudos de Tempo e Movimento , Caminhada
5.
Sensors (Basel) ; 20(3)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012930

RESUMO

Mobility across people with a large range of age was evaluated, for the first time, by using an instrumented timed up and go test (iTUG) based on signals acquired by a single wearable inertial sensor. Eighty healthy participants, from childhood to old age, performed the test, covering walking distances of 3 m and 7 m. Total time, temporal, and velocity parameters of linear and turning subcomponents of the test were quantified. While children, adults, and senior adults exhibited similar values for all the parameters, older adults showed increases in duration and reductions in velocity during the turning phases when compared with the other groups. an increase in velocity was observed during mid turning when the test was performed along the longer distance. Similarity across children, adults, and senior adults indicates that healthy individuals develop the abilities performed in the iTUG early, while the slowing down shown during the turning phases by the older adults may reflect the need to implement adaptive adjustments to face changes of direction. These results emphasize the idea that reducing equipment to a single sensor provides an appropriate quantification when the iTUG is used to investigate a broader age range or different levels of complexity.


Assuntos
Técnicas Biossensoriais , Transtornos Neurológicos da Marcha/fisiopatologia , Equilíbrio Postural/fisiologia , Amplitude de Movimento Articular/fisiologia , Acelerometria , Adolescente , Adulto , Idoso , Criança , Feminino , Transtornos Neurológicos da Marcha/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Fatores de Tempo , Estudos de Tempo e Movimento , Adulto Jovem
6.
Ann Neurol ; 84(5): 674-682, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30225985

RESUMO

OBJECTIVE: Muscle cramps occur in >50% of diabetic patients and reduce the quality of life. No effective treatment is available. We evaluated the clinical effectiveness of botulinum toxin A (BTX-A) injections for treating cramps in diabetic patients with neuropathy. METHODS: This single-center, double-blind, placebo-controlled perspective study investigated the efficacy and safety of BTX-A intramuscular injection for treating calf or foot cramps refractory to common pharmacological drugs. Fifty diabetic patients with peripheral neuropathy and cramps were randomly assigned to 2 matched groups. BTX-A (100 or 30 units) or saline was injected on each side into the gastrocnemius or the small flexor foot muscles. Changes in pain intensity (primary outcome) and cramp frequency were evaluated over the course of 20 weeks after BTX-A administration. Cramp interference in daily life and the electrophysiological cramp threshold frequency were also measured. The treatment was repeated 5 months after first injection in 19 responders. RESULTS: All outcome measures improved significantly after BTX-A compared with placebo. The changes with respect to baseline were already significant after 1 week and persisted up to week 14. Only 5 of 25 (20%) patients were nonresponders (<50% decrease of the primary outcome). The responses to a second BTX-A injection provided results similar to the first administration. Mild pain at the injection site (4/25 cases) was the only adverse event, and it disappeared within 2 to 3 days. INTERPRETATION: Local BTX-A infiltration is an efficacious and safe procedure for obtaining a sustained amelioration of muscle cramps associated with diabetic neuropathy. Ann Neurol 2018;84:682-690.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Neuropatias Diabéticas/complicações , Cãibra Muscular/tratamento farmacológico , Fármacos Neuromusculares/uso terapêutico , Idoso , Diabetes Mellitus Tipo 2/complicações , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cãibra Muscular/etiologia , Resultado do Tratamento
7.
Eur J Appl Physiol ; 115(7): 1441-51, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25682323

RESUMO

PURPOSE: Early identification of postoperative neuromuscular deficits has been advocated to prevent muscle weakness and maximize functional outcomes following anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to investigate neuromechanical changes in compensatory and anticipatory postural adjustments, which play a major role in minimizing unpredictable and predictable disturbances, respectively, as early as 2 months after ACLR. METHODS: Nine young male individuals who underwent ACLR with patellar tendon and nine age-matched healthy controls were exposed to two blocks of ten either unexpected or expected loading perturbations of the knee joint, while semi-reclined on a raised plinth. Amplitude and latency of postural responses in the vastus lateralis (VL), rectus femoris (RF) and biceps femoris (BF) muscles were determined by surface electromyography. RESULTS: Latency of compensatory responses was higher in patients with ACLR than in healthy participants for VL (82 ± 15 vs 68 ± 10 ms, P < 0.05) and RF (81 ± 21 vs 63 ± 10 ms, P < 0.05). Amplitude of compensatory responses was 54 % lower in patients with ACLR than in healthy participants for VL (P < 0.05). Onset of anticipatory responses occurred earlier in patients with ACLR than in healthy participants for VL (-83 ± 45 vs -26 ± 21 ms, P < 0.05), RF (-59 ± 48 vs -10 ± 13 ms, P < 0.05) and BF (-72 ± 42 vs -12 ± 14 ms, P < 0.01). CONCLUSION: Patients with ACLR showed early abnormalities in compensatory and anticipatory postural adjustments, which may reflect the inability to quickly detect sudden changes in muscle length or to completely activate muscles surrounding the knee, and may be addressed by specific training interventions.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/fisiologia , Fenômenos Biomecânicos/fisiologia , Articulação do Joelho/fisiologia , Músculo Esquelético/fisiologia , Músculo Quadríceps/fisiologia , Adulto , Eletromiografia/métodos , Humanos , Masculino , Adulto Jovem
8.
Clin Biomech (Bristol, Avon) ; 111: 106147, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37988778

RESUMO

BACKGROUND: The timing of the effects of botulinum toxin A on spastic muscles is not yet fully clarified. The goal of this study was to follow the temporal changes of surface electromyographic activity of lower limb muscles during walking, after a therapeutic dose of botulinum toxin A injected into the calf muscles of children with spastic cerebral palsy. METHODS: A group of children with spastic equinus foot was administered botulinum toxin A into the gastrocnemius medialis and lateralis muscles. Surface electromyographic activity of the tibialis anterior, gastrocnemius medialis, rectus femoris and medial hamstrings, was recorded before botulinum toxin A injections and after 4, 8, and 16 weeks. Children walked on ground and on a treadmill at an incline of 0% and 12%. The area of electromyographic activity and the index of muscle co-contraction were calculated for specific segments of gait cycle. FINDINGS: Botulinum toxin A did not modify the speed of gait on ground. ANOVA showed significant differences in electromyography during the stance phase segments with a maximum decrease between 4 and 8 weeks' post botulinum toxin A and a full recovery at 16 weeks. A significant co-contraction of rectus femoris/gastrocnemius medialis, between 0 and 20% and 35-50% of the gait cycle, was observed from the 4th to the 8th week post- botulinum toxin A for both treadmill settings. INTERPRETATION: The temporal identification of deterioration/recovery of electromyographic activity as well as of muscle co-contractions, could be key elements in a rehabilitation program planning combined with botulinum toxin A.


Assuntos
Toxinas Botulínicas Tipo A , Paralisia Cerebral , Criança , Humanos , Toxinas Botulínicas Tipo A/uso terapêutico , Paralisia Cerebral/tratamento farmacológico , Eletromiografia , Marcha/fisiologia , Espasticidade Muscular/tratamento farmacológico , Músculo Esquelético , Caminhada
9.
Orphanet J Rare Dis ; 19(1): 39, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308356

RESUMO

BACKGROUND: Congenital disorders of glycosylation (CDG) are genetic diseases caused by impaired synthesis of glycan moieties linked to glycoconjugates. Phosphomannomutase 2 deficiency (PMM2-CDG), the most frequent CDG, is characterized by prominent neurological involvement. Gait disturbance is a major cause of functional disability in patients with PMM2-CDG. However, no specific gait assessment for PMM2-CDG is available. This study analyses gait-related parameters in PMM2-CDG patients using a standardized clinical assessment and instrumented gait analysis (IGA). RESULTS: Seven adult patients with a molecular diagnosis of PMM2-CDG were followed-up from February 2021 to December 2022 and compared to a group of healthy control (HC) subjects, matched for age and sex. Standardized assessment of disease severity including ataxia and peripheral neuropathy along with isometric muscle strength and echo-biometry measurements at lower limbs were performed. IGA spatiotemporal parameters were obtained by means of a wearable sensor in basal conditions. PMM2-CDG patients displayed lower gait speed, stride length, cadence and symmetry index, compared to HC. Significant correlations were found among the used clinical scales and between disease severity (NCRS) scores and the gait speed measured by IGA. Variable reduction of knee extension strength and a significant decrease of lower limb muscle thickness with conserved echo intensity were found in PMM2-CDG compared to HC. CONCLUSIONS: The study elucidates different components of gait disturbance in PMM2-CDG patients and shows advantages of using wearable sensor-based IGA in this frame. IGA parameters may potentially serve as quantitative measures for follow-up or outcome quantification in PMM2-CDG.


Assuntos
Defeitos Congênitos da Glicosilação , Fosfotransferases (Fosfomutases) , Adulto , Humanos , Defeitos Congênitos da Glicosilação/diagnóstico , Defeitos Congênitos da Glicosilação/genética , Estudos de Viabilidade , Fosfotransferases (Fosfomutases)/genética , Marcha , Imunoglobulina A
10.
Children (Basel) ; 10(2)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36832540

RESUMO

Biological bases of autism spectrum disorder (ASD) include both genetic and epigenetic causes. Patients with ASD show anomalies in the profile of certain plasma amino acids, including neuroactive amino acids. Monitoring plasma amino acids may be relevant for patient care and interventions. We evaluated the plasma amino acid profile in samples extracted from dry blood spots by electrospray ionization-tandem mass spectrometry. Fourteen amino acids and eleven amino acid ratios were examined in patients with ASD and intellectual disability (ID), and neurotypical control subjects (TD). The amino acid profile in the ASD group showed reduced levels of ornithine (p = 0.008), phenylalanine (p = 0.042) and tyrosine (p = 0.013). The statistically significant amino acid ratios were Leu+Val/Phe+Tyr (p = 0.002), Tyr/Leu (p = 0.007) and Val/Phe (p = 0.028), such differences remaining significant only in the comparison between ASD and TD. Finally, a positive correlation emerged between the score of the restricted and repetitive behavior on ADOS-2 and the citrulline levels in the ASD group (p = 0.0047). To conclude, patients with ASD may show a distinguishable metabolic profile useful for studying their metabolic pathways in order to develop screening tests and targeted therapies.

11.
Clin Biomech (Bristol, Avon) ; 102: 105896, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36706624

RESUMO

BACKGROUND: Cerebrotendinous xanthomatosis is a rare autosomal-recessive lipid storage disorder causing an elevation in cholestanol and cholesterol levels and their deposition in the central nervous system and tendons with consequent posture and gait disturbances. METHODS: This report shows the case of a 36-year-old male affected by Cerebrotendinous xanthomatosis with static and dynamic instability. We aimed to provide an instrumented quantification of quiet upright standing using a piezoelectric force platform measuring the variations of center of pressure with the foot position 10 cm and 20 cm apart or extra-rotated with an opening angle of 30°, with eyes open or closed. The area of center of pressure and the length of its trajectory in the anterior-posterior and medial-lateral directions were computed. The temporal variability of center of pressure was evaluated by means of the Root Mean Square. FINDINGS: In comparison with a control group, the area, the trajectory length of center of pressure in anterior-posterior and medial-lateral directions and the temporal variability increased in all static conditions. Intra-patient comparison showed that foot position 10 cm apart was the position that most influenced stability causing a marked worsening of area and trajectory length of center of pressure in both anterior-posterior and medial-lateral directions, particularly for the eyes closed condition. INTERPRETATION: We found a large static instability due to internal neural and biomechanical constraints causing an insufficiency of ankle strategy. A physical therapy program based on instrumented proprioceptive exercises is to be implemented to teach the use of a hip strategy.


Assuntos
Xantomatose Cerebrotendinosa , Masculino , Humanos , Adulto , Tornozelo , Tendões , Pé/fisiologia , Articulação do Tornozelo
12.
Minerva Med ; 114(3): 357-371, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35332756

RESUMO

Vitamin D deficiency is involved in the etiology of a broad range of diseases. Recently, some studies have shown a link between vitamin D and susceptibility to the onset of chronic obstructive pulmonary disease (COPD). COPD is characterized by chronic inflammation and irreversible airway obstruction. Systemic inflammation in COPD patients is associated with a decline in lung function. In addition, inflammation causes various extra-pulmonary symptoms, including muscle deterioration that leads to reduced strength and fatigue endurance, especially in muscles of the lower limb. In COPD the pathophysiological changes related to the inflammatory state affect oxidant-antioxidant balance, which is one of the main mechanisms promoting the progression of this disease and exacerbations. Vitamin D exerts beneficial effects and exhibits anti-inflammatory actions. Vitamin D deficiency in COPD patients affects inflammation, oxidative stress and mitochondrial impairment and can generate the development of skeletal atrophy. This systematic review offers a better understanding of the molecular mechanisms linking vitamin D deficiency to COPD and muscle weakness, and aims to establish whether vitamin D supplementation could be useful to mitigate inflammation in COPD patients.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Deficiência de Vitamina D , Humanos , Vitamina D , Doença Pulmonar Obstrutiva Crônica/complicações , Vitaminas , Músculos , Inflamação/complicações , Anti-Inflamatórios
13.
J Autism Dev Disord ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38109035

RESUMO

This study was undertaken to set a novel developmental screening test for autism spectrum disorder (ASD) using the Griffiths Scales of Child Development (Griffith III) (Green et al., 2016; Stroud et al., 2016), in order to intercept the early atypical developmental patterns indicating ASD risk in the first 3 years of age. An observational and interactive ASD screener, the Developmental Autism Early Screening (DAES), was developed by detecting Griffiths III items differentiating toddlers with ASD risk from those with global developmental delay (DD) or neurotypical development. The DAES was validated with ASD-specific diagnostic instruments (ADOS-2) and the cut-off score based on sensitivity, specificity and positive predictive value that best differentiates between ASD and non-ASD children was identified. We enrolled a total sample of 297 subjects, including children at risk for ASD or DD and neurotypical children. At a cut-off score of 12.5, the DAES had a sensitivity of 93%, specificity of 98.4%, positive predictive value of 96.3% and negative predictive value of 96.9% for identifying children at risk for ASD from non-ASD participants (DD/neurotypical children). The DAES total score correlated significantly with the ADOS-2 calibrated severity scores (CSS) (R = 0.53, p < 0.001). Three ASD risk ranges were identified according to DAES total and ADOS-2 CSS: Little-to-no risk (CSS: 1-3, DAES: 1-7); Mild-to-moderate risk (CSS: 4-5, DAES: 8-14); Moderate-to-severe risk (CSS: 6-10, DAES ≥ 15). The DAES provides a direct approach based on developmental profiles to stratify risk for ASD in early childhood ensuring at risk children the most appropriate diagnostic procedures and targeted intervention.

14.
Biomedicines ; 10(4)2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35453648

RESUMO

Skeletal muscle dysfunction is frequently associated with chronic obstructive pulmonary disease (COPD), which is characterized by a permanent airflow limitation, with a worsening respiratory disorder during disease evolution. In COPD, the pathophysiological changes related to the chronic inflammatory state affect oxidant-antioxidant balance, which is one of the main mechanisms accompanying extra-pulmonary comorbidity such as muscle wasting. Muscle impairment is characterized by alterations on muscle fiber architecture, contractile protein integrity, and mitochondrial dysfunction. Exogenous and endogenous sources of reactive oxygen species (ROS) are present in COPD pathology. One of the endogenous sources of ROS is represented by mitochondria. Evidence demonstrated that vitamin D plays a crucial role for the maintenance of skeletal muscle health. Vitamin D deficiency affects oxidative stress and mitochondrial function influencing disease course through an effect on muscle function in COPD patients. This review will focus on vitamin-D-linked mechanisms that could modulate and ameliorate the damage response to free radicals in muscle fibers, evaluating vitamin D supplementation with enough potent effect to contrast mitochondrial impairment, but which avoids potential severe side effects.

15.
J Clin Med ; 10(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34501263

RESUMO

A greater proportion of glycolytic muscle fibers is a manifestation of skeletal muscle dysfunction in Chronic Obstructive Pulmonary Disease (COPD). Here, we propose to use the spectral analysis of the electromyographic signal as a non-invasive approach to investigate the fiber muscle composition in COPD. We recorded the electromyographic activity of Rectus Femoris (RF), Vastus Lateralis (VL), Vastus Medialis (VM) and Biceps Femoris (BF) muscles, in ten patients and ten healthy individuals, during non-fatiguing, flexion-extension leg movements. The mean (MNF) and median frequencies (MDF) were calculated, and the most common profiles of electromyographic power spectrum were characterized by using the principal component analysis. Frequency parameters showed higher values in patients with COPD than in the control group for the RF (+25% for MNF; +21% for MNF), VL (+16% for MNF; 16% for MNF) and VM (+22% for MNF; 22% for MNF) muscles during the extension movements and for the BF (+26% for MNF; 34% for MNF) muscle during flexion movements. Spectrum profiles of the COPD patients shifted towards the higher frequencies, and the changes in frequency parameters were correlated with the level of disease severity. This shift of frequencies may indicate an increase in glycolytic muscle fibers in patients with COPD. These results, along with the non-fatigable nature of the motor task and the adoption of a non-invasive method, encourage to use electromyographic spectral analysis for estimating muscle fiber composition in patients with COPD.

16.
Sci Rep ; 11(1): 18077, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508166

RESUMO

Chronic obstructive pulmonary disease (COPD) produces skeletal muscle atrophy and weakness, leading to impairments of exercise performance. The mechanical work needed for movement execution is also provided by the passive tension developed by musculoarticular connective tissue. To verify whether COPD affects this component, the passive viscoelastic properties of the knee joint were evaluated in 11 patients with COPD and in 11 healthy individuals. The levels of stiffness and viscosity were assessed by means of the pendulum test, consisting in a series of passive leg oscillations. In addition, to explore the contribution of passive tension in the mechanical output of a simple motor task, voluntary leg flexion-extension movements were performed. Patients with COPD showed a statistically significant reduction in stiffness and viscosity compared to controls. Voluntary execution of flexion-extension movements revealed that the electromyographic activity of the Rectus Femoris and Biceps Femoris was lower in patients than in controls, and the low viscoelastic tension in the patients conditioned the performance of active movements. These results provide novel insights on the mechanism responsible for the movement impairments associated with COPD.


Assuntos
Articulações/fisiopatologia , Músculo Esquelético/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Estudos de Casos e Controles , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Contração Muscular , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/etiologia , Amplitude de Movimento Articular , Reflexo
17.
J Pers Med ; 11(6)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199819

RESUMO

Patients with autism spectrum disorder (ASD) may have an increase in blood acyl-carnitine (AC) concentrations indicating a mitochondrial fatty acid ß-oxidation (mtFAO) impairment. However, there are no data on systematic mtFAO analyses in ASD. We analyzed tritiated palmitate oxidation rates in fibroblasts from patients with ASD before and after resveratrol (RSV) treatment, according to methods used for the diagnosis of congenital defects in mtFAO. ASD participants (N = 10, 60%; male; mean age (SD) 7.4 (3.2) years) were divided in two age-equivalent groups based on the presence (N = 5) or absence (N = 5) of elevated blood AC levels. In addition, electron transport chain (ETC) activity in fibroblasts and muscle biopsies and clinical characteristics were compared between the ASD groups. Baseline fibroblast mtFAO was not significantly different in patients in comparison with control values. However, ASD patients with elevated AC exhibited significantly decreased mtFAO rates, muscle ETC complex II activity, and fibroblast ETC Complex II/III activity (p < 0.05), compared with patients without an AC signature. RSV significantly increased the mtFAO activity in all study groups (p = 0.001). The highest mtFAO changes in response to RSV were observed in fibroblasts from patients with more severe symptoms on the Social Responsiveness Scale total (p = 0.001) and Awareness, Cognition, Communication and Motivation subscales (all p < 0.01). These findings suggested recognition of an ASD patient subset characterized by an impaired mtFAO flux associated with abnormal blood AC. The study elucidated that RSV significantly increased fibroblast mtFAO irrespective of plasma AC status, and the highest changes to RSV effects on mtFAO were observed in the more severely affected patients.

18.
Cerebellum ; 9(1): 103-10, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20013085

RESUMO

Neural representations of limb movement kinematic parameters are common among central nervous system structures involved in motor control, such as the interpositus nucleus of the cerebellum. Much experimental evidence indicates that neurons in the interpositus may encode limb kinematic parameters both during active, voluntary actions and during limb motion imposed passively, which entrains only sensory afferents. With respect to the sensory processing of information related to movement kinematics, we show that interpositus neuronal activity can parse out the directional from the scalar component (i.e., the movement speed) of the velocity vector. Moreover, a differential role for the anterior and posterior portion of interpositus in encoding these parameters emerged from these data, since the activity of the posterior interpositus was specifically associated to changes of movement speed. Limb movement representations in the interpositus nucleus may be instrumental for the control of goal-directed movements such as shaping hand during grasping or precise foot placement during gait. Finally, we discuss the idea that sensory information about the movement kinematics contribute to both feedback and anticipatory processes for limb movement control.


Assuntos
Fenômenos Biomecânicos/fisiologia , Núcleos Cerebelares/fisiologia , Extremidades/fisiologia , Movimento/fisiologia , Potenciais de Ação/fisiologia , Animais , Extremidades/inervação , Retroalimentação Sensorial/fisiologia , Humanos , Vias Neurais/fisiologia , Neurônios/fisiologia , Desempenho Psicomotor/fisiologia
19.
Cerebellum ; 9(2): 249-58, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20169431

RESUMO

The interpositus nucleus (IN) receives a large amount of sensory information from the limbs and, in turn, elaborates signals for movement control. In this paper, we tried to gather evidence on the possibility that neurons in the IN may elaborate sensory representations of the forelimb kinematics and, particularly, of the movement velocity vector. For this purpose, the forepaw of anesthetized rats was attached to a computer-controlled robot arm displaced passively along two types of trajectories (circular and figure eight), with the limb joints unconstrained. The firing activity of single cells was recorded and related to limb position and the two components of the movement velocity vector, namely, movement speed and direction. By using multiple regression analysis, we found that 12 out of 85 (14%) neurons were modulated by position, 18 out of 85 (21%) neurons were modulated by direction, 24 out of 85 (28%) neurons were modulated by movement speed, and 31 out of 85 (37%) neurons were sensitive to the full movement velocity vector. Most of the neurons modulated only by the speed component of the velocity vector (19 out of 24) were located in the posterior portion of the IN, whereas neurons in the anterior portion were mostly related to both components of the velocity vector. These results suggest that sensory information related to whole-limb movement velocity may be encoded by the IN, indicating also that the posterior interpositus may preferentially represent movement speed.


Assuntos
Córtex Cerebelar/fisiologia , Movimento/fisiologia , Extremidade Superior/fisiologia , Potenciais de Ação/fisiologia , Animais , Comportamento Animal , Córtex Cerebelar/citologia , Masculino , Modelos Neurológicos , Análise Multivariada , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Estatística como Assunto
20.
Brain Sci ; 11(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374653

RESUMO

The benefits of functional electrical stimulation during cycling (FES-cycling) have been ascertained following spinal cord injury. The instrumented pendulum test was applied to chronic paraplegic patients to investigate the effects of FES-cycling of different duration (20-min vs. 40-min) on biomechanical and electromyographic characterization of knee mobility. Seven adults with post-traumatic paraplegia attended two FES-cycling sessions, a 20-min and a 40-min one, in a random order. Knee angular excursion, stiffness and viscosity were measured using the pendulum test before and after each session. Surface electromyographic activity was recorded from the rectus femoris (RF) and biceps femoris (BF) muscles. FES-cycling led to reduced excursion (p < 0.001) and increased stiffness (p = 0.005) of the knee, which was more evident after the 20-min than 40-min session. Noteworthy, biomechanical changes were associated with an increase of muscle activity and changes in latency of muscle activity only for 20-min, with anticipated response times for RF (p < 0.001) and delayed responses for BF (p = 0.033). These results indicate that significant functional changes in knee mobility can be achieved by FES-cycling for 20 min, as evaluated by the pendulum test in patients with chronic paraplegia. The observed muscle behaviour suggests modulatory effects of exercise on spinal network aimed to partially restore automatic neuronal processes.

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