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1.
Behav Brain Res ; 476: 115191, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39122092

RESUMO

BACKGROUND: Persons with multiple sclerosis (PwMS) suffer from sleep disturbances, fatigue and pain, which can be due, at least in part, to decreased levels of endogenous melatonin. These alterations could exacerbate postural instability, gait disorders and fall risk. Acute effects of exogenous melatonin on physical disorders have been studied in PwMS but its long-term effects on these parameters have not been explored yet in this population. This study aimed to determine the impact of chronic melatonin intake on dynamic postural stability, walking performance and fall risk in PwMS. METHODS: This randomized placebo-controlled study included 27 PwMS who were assigned to either melatonin group (MG, n=15) or placebo group (PG, n=12) (3 mg/night for 12 weeks). Dynamic postural balance (force platform), walking performance (locometer) and fall risk (Four Square Step Test) were evaluated pre (T0)- and post (T1)-intervention. Sleep quality (Pittsburgh Sleep Quality Index (PSQI)), fatigue perception (Fatigue Severity Scale (FSS)), neuropathic pain (Neuropathic Pain Questionnaire 4 (DN4)) and quality of life (International Multiple Sclerosis (MS) Quality of Life Questionnaire) were also assessed at T0 and T1. RESULTS: The center of pressure mean velocity decreased in MG compared with PG in the frontal plane (22.98 %, p=0.028). Stride length and walking speed increased in MG comparatively with PG (18.09 %, p=0.036; 9.65 %, p=0.025, respectively). The PSQI (55.89 %, p<0.001), FSS (32.38 %, p=0.003) and DN4 (32.41 %, p=0.035) scores decreased in MG compared with PG. CONCLUSION: 12-week melatonin supplementation can be recommended for managing MS-related gait disorders and dynamic postural imbalance. This therapy may also be prescribed for PwMS due to its anti-fatigue and analgesic effects as well as its benefits on sleep quality. CLINICAL REGISTRATION: This study was prospectively recorded in the Pan African Clinical Trial Registry database (PACTR202007465309582) (https://pactr.samrc.ac.za/.).


Assuntos
Melatonina , Esclerose Múltipla , Equilíbrio Postural , Caminhada , Humanos , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/complicações , Esclerose Múltipla/fisiopatologia , Equilíbrio Postural/efeitos dos fármacos , Equilíbrio Postural/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Melatonina/administração & dosagem , Melatonina/farmacologia , Caminhada/fisiologia , Adulto , Fadiga/tratamento farmacológico , Fadiga/fisiopatologia , Qualidade de Vida , Acidentes por Quedas/prevenção & controle , Qualidade do Sono , Método Duplo-Cego
2.
Neurodegener Dis Manag ; 14(5): 173-187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39439238

RESUMO

Aim: Studying the effects of self-paced concurrent high-intensity interval training and resistance training (HIIT-RT) on respiratory function, cardiopulmonary fitness and fatigue perception in patients with multiple sclerosis (PwMS).Methods: Twenty-three PwMS were randomized into a 12-week training group (three times per week) (TG, n = 11) or a control group (CG, n = 12). Lung function (spirometry), aerobic capacity (graded cardiopulmonary-exercise-testing) and perceived fatigue (Fatigue Severity Scale (FSS)) were evaluated pre- and post-intervention.Results: The forced vital capacity (p = 0.036, Hedges'g (g) = 0.93), forced expiratory time (p = 0.045, g = 0.88), peak expiratory flow (p = 0.043, g = 0.89) increased in TG compared with CG. The TG showed an increase in peak aerobic power (p = 0.004, g = 1.34) and peak oxygen uptake (p < 0.001, g = 2.58) compared with CG. There was a decrease in ventilatory equivalent for carbon dioxide (p = 0.02, g = 1.02) and FSS scores (p < 0.001, g = 1.72) in TG comparatively with CG.Conclusion: 12-week self-paced HIIT-RT enhanced lung function as well as aerobic fitness, and alleviated fatigue perception in PwMS.


[Box: see text].


Assuntos
Aptidão Cardiorrespiratória , Fadiga , Esclerose Múltipla , Humanos , Masculino , Feminino , Fadiga/etiologia , Fadiga/fisiopatologia , Adulto , Esclerose Múltipla/complicações , Esclerose Múltipla/fisiopatologia , Aptidão Cardiorrespiratória/fisiologia , Pessoa de Meia-Idade , Treinamento Intervalado de Alta Intensidade , Treinamento Resistido/métodos , Testes de Função Respiratória , Pulmão/fisiopatologia , Percepção/fisiologia
3.
eNeurologicalSci ; 37: 100525, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39309450

RESUMO

Purpose: To analyze changes in peripapillary retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness in migraine patients with and without aura compared to healthy controls and to identify factors influencing the occurrence of these anomalies. Methods: This is a cross-sectional case-control study including migraine patients and control subjects. All patients and controls underwent a complete ophthalmological examination, RNFL and GCC thickness measurements using a spectral domain-OCT device.The duration of migraine, the frequency and duration of migraine attacks, the migraine disability assessment (MIDAS) and migraine severity scale (MIGSEV) questionnaire scores were recorded. Results: One hundred and twenty eyes from 60 patients (60 eyes in the migraine without aura (MWoA) group and 60 eyes in the migraine with aura (MWA) group) were included. Control group included 30 age and gender matched healthy participants (60 eyes). OCT revealed that RNFL and GCC thickness were significantly reduced in the migraine without aura (MWoA) and in the migraine with aura (MWA) groups compared to the control group and in the migraine with aura (MWA) group compared to the migraine without aura (MWoA) group. Prolonged disease duration was associated to decreased GCC thickness. RNFL and GCC thickness were correlated to disease severity, attack frequency and duration. In the multivariate study, duration of migraine and attack frequency were the main determinant factors of nasal GCC thickness. Disease severity was the main determinant of RNFL and GCC thickness, with the exception of the nasal sector. Conclusion: Our study emphasize the significant impact of both types of migraine on retinal structures. OCT would serve as a valuable biomarker in migraine.

4.
J Clin Neurosci ; 126: 348-352, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39032387

RESUMO

Migraine, classified as a neurovascular disease, has been identified as a potential risk factor for ocular vascular complications. Our study aimed to compare retinal vessel density and perfusion density between subjects with migraine and healthy subjects using optical coherence tomography angiography (OCTA). In this cross-sectional case-control study, we enrolled 30 migraine subjects with aura (MWA), 30 migraine subjects without aura (MWOA) and 30 age and gender-matched healthy controls (HC). The foveal avascular zone (FAZ) in superficial capillary plexus (SCP), Vessel density (VD) and perfusion density (PD) in SCP and deep capillary plexus (DCP) were assessed in a 3 × 3 mm scan of the macula with the swept source OCT. Results indicated that the FAZ of MWA and MWOA subjects was significantly larger from HC. Also, FAZ of MWA was larger from MWOA. VD and PD in both SCP and DCP were significantly reduced in both MWA and MWOA groups compared to HC. However, VD and PD did not show significant differences among MWA and MWOA. Additionally, the duration of disease was the main determinant of the FAZ. In conclusion, the FAZ in the SCP, VD and PD in the SCP and DCP of the macula were affected in both MWA and MWOA. FAZ, specifically, was increased with the evolution of the disease. These findings might contribute to an increased risk of ocular vascular complications among subjects with migraine and could potentially use OCTA as a biomarker for this population.


Assuntos
Fóvea Central , Enxaqueca com Aura , Enxaqueca sem Aura , Vasos Retinianos , Tomografia de Coerência Óptica , Humanos , Feminino , Masculino , Adulto , Estudos Transversais , Tomografia de Coerência Óptica/métodos , Fóvea Central/irrigação sanguínea , Fóvea Central/diagnóstico por imagem , Fóvea Central/patologia , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Estudos de Casos e Controles , Enxaqueca com Aura/diagnóstico por imagem , Enxaqueca com Aura/fisiopatologia , Enxaqueca sem Aura/diagnóstico por imagem , Enxaqueca sem Aura/fisiopatologia , Pessoa de Meia-Idade , Adulto Jovem
5.
Tunis Med ; 102(4): 217-222, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38746961

RESUMO

INTRODUCTION: Ischemic Stroke in young adults is a real public health problem; it's a major cause of disability, alters quality of life and has a great socio-economic impact. AIM: determine risk factors and specify the etiology of arterial ischemic stroke in young Tunisian adults. METHODS: In this 5 years retrospective study (2015-2020), we included all young adults (18-50 years) admitted for arterial ischemic stroke (AIS). Risk factors were registered and analyzed. All patients were investigated using a standard protocol: biological tests, brain imaging, carotid ultrasound and cardiac assessment. Additional investigations were carried out at the discretion of the treating physician. The cause of ischemic stroke was classified according to the TOAST criteria. RESULTS: We collected 200 patients with AIS. The mean age was 41.37 years ± 6.99. Traditional vascular risk factors were observed in more than 1/4 patients. A definite cause of stroke was identified in 120 patients. Cardio-embolic causes were the most common among our patients (19%) followed by atherosclerosis of the large arteries (11.5%). Other determined etiologies were found in 27.5% of patients. The etiology remained unclear in 40% of cases: undetermined despite complete investigation in 17.5%, undetermined and incompletely investigated 14.5 % and more than one potential pathomechanisms in 8%. CONCLUSION: Through this study, we demonstrated the diversity of etiology of stroke in young Tunisian adults. Changes of lifestyle are responsible for the occurrence of the traditional risk factors at an early age. Rheumatic heart diseases remain a frequent cause of AIS in our area.


Assuntos
AVC Isquêmico , Humanos , Tunísia/epidemiologia , Adulto , Masculino , AVC Isquêmico/epidemiologia , AVC Isquêmico/etiologia , AVC Isquêmico/diagnóstico , Feminino , Pessoa de Meia-Idade , Adulto Jovem , Estudos Retrospectivos , Fatores de Risco , Adolescente , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/diagnóstico
6.
Pan Afr Med J ; 47: 46, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681104

RESUMO

COVID-19 vaccination side effects have been increasingly reported, including new-onset autoimmune diseases such as chronic arthritis, thrombocytopenia, Guillain-Barré syndrome (GBS), and more recently chronic inflammatory demyelinating polyneuropathies (CIDP). Molecular mimicry and vaccine adjuvants appear to be important contributors to immune-mediated neuropathies. However, whether the link between the COVID-19 vaccine and these autoimmune disorders is coincidental or causal remains uncertain. We describe the ever-reported case of acute-onset CIDP following the Oxford/AstraZeneca vaccine in Tunisia. The patient is a 41-year-old man who presented with acute, worsening weakness of the four limbs. The symptoms appeared 15 days after his first dose of the AstraZeneca vaccine. The diagnosis of GBS was initially confirmed according to the clinical features, the albumino-cytological dissociation in the cerebrospinal fluid (CSF), and the electroneuromyography (ENMG) findings. Serum workup for all known infections associated with immune-mediated neuropathy was negative. The patient was treated with plasma exchange without initial improvement followed by aggravation of the symptomatology after an interval of four and a half months. Control ENMG showed signs of CIDP meeting the European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) criteria of 2021. The patient was treated with maintenance intravenous immunoglobulin and oral corticosteroids. Neurological examination 3 months after discharge showed partial improvement. Worldwide, cases of demyelinating polyneuropathies post-COVID-19 vaccination are increasingly reported. The acute onset of CIDP might lead to a misdiagnosis of GBS. Awareness of this complication and distinction from GBS enables early relay with maintenance treatment to prevent relapses and severe complications. Post-COVID neuropathies are found to be more frequently linked to the AstraZeneca vaccine, however, temporal association does not confirm causal association.


Assuntos
Vacinas contra COVID-19 , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Adulto , Humanos , Masculino , ChAdOx1 nCoV-19 , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/induzido quimicamente , Tunísia
7.
Clin Neurol Neurosurg ; 238: 108165, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38428060

RESUMO

BACKGROUND: Decreased endogenous melatonin concentrations in people with multiple sclerosis (PwMS) are associated with fatigue and pain that impair postural balance and muscle strength. Melatonin ingestion had analgesic and anti-fatigue effects. However, the acute effect of exogenous melatonin on dynamic postural stability and muscle strength has not been studied yet in PwMS. This study aimed to investigate the safety and the efficacy of a nighttime melatonin intake on dynamic postural balance and lower-extremity muscle strength the following morning in PwMS. METHODS: Fourteen PwMS (28.36 ± 6.81 years) were assessed (8 a.m.) pre- and post-acute intake of melatonin or placebo (6mg, 30 minutes before nocturnal bedtime). Evaluated parameters included dynamic postural balance (force platform), lower-extremity muscle strength [Five-Repetition Sit-To-Stand Test (5-STST)], hand dexterity (Nine-Hole Peg Test), nociceptive pain [Visual Analogue Scale (VAS)], neuropathic pain [Neuropathic Pain 4 Questions (DN4)], sleep quality and fatigue perception [Hooper Index (HI)]. RESULTS: In the frontal plane, melatonin reduced the center of pressure (CoP) path length (CoPL), CoPL in the anteroposterior axis (CoPLY) and CoP sway area (CoPAr) compared with placebo by 7.56% (p=0.02, Cohens'd (d)=1.24), 19.27% (p<0.001, d=2.60) and 13.82% (p<0.001, d=2.02), respectively. Melatonin induced a higher decrease in these posturographic parameters compared with placebo in the sagittal plane [CoPL: 9.10% (p=0.005, d=1.02), CoPLY: 4.29% (p=0.025, d=1.07) and CoPAr: 7.45% (p=0.038, d=0.74)]. Melatonin decreased 5-STST duration as well as VAS, DN4, HI-fatigue and HI-sleep scores compared with placebo by 8.19% (p=0.008, d=1.19), 5.74% (p=0.04, d=0.82), 27.30% (p=0.023, d=0.98), 40.15% (p=0.044, d=0.85) and 30.16% (p=0.012, d=1.10), respectively. CONCLUSION: This preliminary study, among PwMS, showed that acute melatonin ingestion was safe and efficient for improving dynamic postural stability and lower-extremity muscle strength probably through its analgesic and anti-fatigue effects.


Assuntos
Melatonina , Esclerose Múltipla , Neuralgia , Humanos , Esclerose Múltipla/tratamento farmacológico , Melatonina/farmacologia , Melatonina/uso terapêutico , Equilíbrio Postural/fisiologia , Força Muscular/fisiologia , Fadiga/tratamento farmacológico , Analgésicos , Ingestão de Alimentos
9.
Mult Scler Relat Disord ; 84: 105509, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422634

RESUMO

Cerebrospinal fluid (CSF) isoelectrofocusing (IEF) is considered as the gold standard for detecting an intrathecal synthesis of IgG, which is a hallmark of multiple sclerosis (MS). This corresponds to the presence of CSF-restricted IgG oligoclonal bands (OCB) (typically type 2 pattern). Moreover, this technique can also detect a systemic immune reaction with passive transfer of IgG (type 3 and 4 patterns) for which the clinical relevance is less understood. The aim of our study was to determine the frequency and disease associations of IEF type 3 and 4 patterns and to investigate the potential usefulness of including quantitative data (IgG index and Reiber Diagram) in interpreting such IEF profiles. Among 544 patients who underwent CSF IEF (Hydragel CSF isofocusing kit, Sebia®, France) in our Laboratory during a six-year-period, those who presented type 3 or 4 patterns were selected. Clinical data and results of other immunological tests were analyzed for 27 patients followed in the Neurological Department. Frequencies of type 3 and type 4 patterns were relatively low (2.3 % and 3.4 % respectively). Among patients with type 3 pattern included in our study (n = 10), 5 were diagnosed with MS. For the 5 other patients, the diagnosis was a clinically isolated syndrome (CIS) (2 cases), a probable auto-immune encephalitis (2 cases) and a possible genetic neurodegenerative disease (1 case). MS patients had an IgG index >0.7 and fell into area 4 of Reiber diagram while non-MS patients had an IgG index <0.7 and fell into area 1, except the last case. Regarding type 4 pattern (n = 17), the diagnoses were as follows: MS (3), CIS (4), Neuromyelitis optica spectrum disorders with positive anti-AQP4 antibodies (3) and anti-NMDAR autoimmune encephalitis (1). The remaining cases had central nervous system impairment related to vascular, metabolic or tumoral etiologies (3) or peripheral nervous system impairment (3). In this group (type 4 pattern), IgG index was <0.7 in 15/17 cases. Interpretation using Reiber diagram showed an abnormal blood-brain barrier for 8/17 patients. Type 3 and 4 IEF patterns are infrequently observed in routine neurology practice. It is important for the diagnostic laboratory professional as well as for the neurologist to understand their clinical relevance. Our findings highlight the contribution of quantitative evaluation of CSF (IgG index, Reiber diagram) for the interpretation of such situations. Despite the small size of our study population, our results emphasize the importance of reporting the exact type of IEF pattern and not only the positivity or not of OCB.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Esclerose Múltipla , Doenças Neurodegenerativas , Humanos , Relevância Clínica , Imunoglobulina G/líquido cefalorraquidiano , Bandas Oligoclonais/líquido cefalorraquidiano , Testes Imunológicos
10.
J Med Biochem ; 42(3): 364-375, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37814621

RESUMO

Background: During the last decade, vitamin D (VitD) has become a topic of interest in immune regulation, especially in multiple sclerosis (MS) disease. Amongst the wide range of effects reported for this vitamin on the immune system, a regulatory role on cytokines production has been described. Our aim is to analyze the status of VitD and its correlation with the circulating inflammation and the intrathecal humoral response during MS. Methods: We analyzed samples of 318 individuals: 108 MS patients and 210 controls. Determination of 25-(OH) VitD3 level in serum was made using electrochemiluminescence method. Circulating inflammatory cytokines (IL-6, IL-8, IL-10, TNF-a, IL12p70 and IL-1b) were investigated using Cytometer Bead Array Technology. The central humoral response was characterized using CSF isofocusing test and IgG Index calculation. Results: As expected, mean value of VitD was significantly lower in MS group (26 nmol/L) than in control group (34.75 nmol/L) (p=0.002), with a severe deficiency in 67% of MS patients. Mean value of VitD was significantly lower in MS female patients. Regarding cytokines, mean value of TNFa was significantly higher in MS patients with oligoclonal bands of IgG in the CSF. IL6 was positively correlated with IgG level in serum of MS patients. Conclusions: Our results support the association of VitD deficiency with MS, especially in female patients of our region. However, the vitamin level seems to not correlate with inflammatory cytokines nor with disability. Interestingly, TNFa and IL6 levels were correlated with the intrathecal synthesis of IgG and the circulating IgG level, respectively.

11.
Neuromuscul Disord ; 33(10): 718-727, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37716854

RESUMO

Dysferlinopathy is a rare group of hereditary muscular dystrophy with an autosomal recessive mode of inheritance caused by a mutation in the DYSF gene. It encodes for the dysferlin protein, which has a crucial role in multiple cellular processes, including muscle fiber membrane repair. This deficit has heterogeneous clinical presentations. In this study, we collected 20 Tunisian patients with a sex ratio of 1 and a median age of 50.5 years old (Interquartile range (IQR) = [36,5-54,75]). They were followed for periods ranging from 5 to 48 years. The median age at onset was 17 years old (IQR = [16,8-28,4]). Five major phenotypes were identified: Limb-girdle muscular dystrophy (LGMDR2) (35%), a proximodistal phenotype (35%), Miyoshi myopathy (10%),  Distal myopathy with anterior tibial onset (DMAT) (10%), and asymptomatic HyperCKemia (10%). At the last evaluation, more than half of patients (55%) were on wheelchair. Loss of ambulation occurred generally during the fourth decade. After 20 years of disease progression, two patients with a proximodistal phenotype (10%) developed dilated cardiomyopathy and mitral valve regurgitation. Restrictive respiratory syndrome was observed in three patients (DMAT: 1 patient, proximodistal phenotype: 1 patient, LGMDR2: 1 patient). Genetic study disclosed five mutations. We observed clinical heterogeneity between families and even within the same family. Disease progression was mainly slow to intermediate regardless of the phenotype.


Assuntos
Miopatias Distais , Distrofia Muscular do Cíngulo dos Membros , Humanos , Pessoa de Meia-Idade , Prognóstico , Tunísia/epidemiologia , Proteínas de Membrana/genética , Proteínas Musculares/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Distrofia Muscular do Cíngulo dos Membros/metabolismo , Disferlina/genética , Miopatias Distais/genética , Progressão da Doença , Mutação , Patrimônio Genético
12.
PLoS One ; 18(7): e0288030, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37471350

RESUMO

OBJECTIVES: Stroke represents a health care challenge to most parts of the world including the Middle East and North Africa (MENA) region. The MENA represents 6% of the world population with an age-standardized stroke rate of 87.7 (78.2-97.6) per 100,000 population. This number is subject to increase given that the cause of morbidity has recently shifted from infectious diseases to non-communicable diseases. Thus, in the coming years, treatment of stroke will pose a major burden on MENA countries which mostly lie in the low to middle income economies. Accordingly, we need to study the state of MENA stroke services in order to recognize and further inform policy makers about any gaps that need to be bridged in this domain. METHODS AND RESULTS: Stroke specialists representing 16 countries filled an online survey that included: screening for risk factors, acute management, diagnostics, medications, post-discharge services, and stroke registries. Results showed that 11 countries screen for risk factors, 16 have neuroimaging studies, 15 provide intravenous thrombolysis (IVT), 13 mechanical thrombectomy (MT) while medications for secondary prevention are available in all countries. However, stroke units are not equally available and even absent in 4 countries, and despite the availability of IVT yet, the rate of administration is still low in 6 countries (<5%), and ranges from 5-20% in 7 countries. Stroke registries and training still need to be implemented in most countries. CONCLUSION: Although imaging, revascularization therapies and medications for secondary prevention are available in most MENA countries, yet the rate of revascularization is low, so is the number of stroke units insufficient in some countries. Additionally, registries and structured training are still defective. Further field studies are required for more accurate determination of the status of stroke services in the MENA region.


Assuntos
Serviços de Saúde , Avaliação das Necessidades , Acidente Vascular Cerebral , Humanos , África do Norte/epidemiologia , Estudos Transversais , Pesquisas sobre Atenção à Saúde , Serviços de Saúde/estatística & dados numéricos , Oriente Médio/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia
13.
Clin EEG Neurosci ; : 15500594221148285, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604821

RESUMO

Motor imagery (MI) signals recorded by electroencephalography provide the most practical basis for conceiving brain-computer interfaces (BCI). These interfaces offer a high degree of freedom. This helps people with motor disabilities communicate with the device by tackling a sequence of motor imagery tasks. However, the extracting user-specific features and increasing the accuracy of the classifier remain as difficult tasks in MI-based BCI. In this work, we propose a new method using artificial neural network (ANN) enhancing the performance of the motor imagery classification. Feature extraction techniques, like time domain parameters, band power features, signal power features, and wavelet packet decomposition (WPD), are studied and compared. Four classification algorithms are implemented which are Quadratic Discriminant Analysis, k-Nearest Neighbors, Linear Discriminant Analysis, and proposed ANN architecture. We added Batch Normalization layers to the proposed ANN architecture to improve the learning time and accuracy of the neural network. These layers also alleviate the effect of weight initialization and the addition of a regularization effect on the network. Our proposed method using ANN architecture achieves 0.5545 of kappa and 58.42% of accuracy on the BCI Competition IV-2a dataset. Our results show that the modified ANN method, with frequency and spatial features extracted by WPD and Common Spatial Pattern, respectively, offers a better classification compared to other current methods.

14.
J Digit Imaging ; 36(2): 468-485, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36478312

RESUMO

Multiple sclerosis (MS) is one of the most serious neurological diseases. It is the most frequent reason of non-traumatic disability among young adults. MS is an autoimmune disease wherein the central nervous system wrongly destructs the myelin sheath surrounding and protecting axons of nerve cells of the brain and the spinal cord which results in presence of lesions called plaques. The damage of myelin sheath alters the normal transmission of nerve flow at the plaques level, consequently, a loss of communication between the brain and other organs. The consequence of this poor transmission of nerve impulses is the occurrence of various neurological symptoms. MS lesions cause mobility, vision, cognitive, and memory disorders. Indeed, early detection of lesions provides an accurate MS diagnosis. Consequently, and with the adequate treatment, clinicians will be able to deal effectively with the disease and reduce the number of relapses. Therefore, the use of magnetic resonance imaging (MRI) is primordial which is proven as the relevant imaging tool for early diagnosis of MS patients. But, low contrast MRI images can hide important objects in the image such lesions. In this paper, we propose a new automated contrast enhancement (CE) method to ameliorate the low contrast of MRI images for a better enhancement of MS lesions. This step is very important as it helps radiologists in confirming their diagnosis. The developed algorithm called BDS is based on Brightness Preserving Dynamic Fuzzy Histogram Equalization (BPDFHE) and Singular Value Decomposition with Discrete Wavelet Transform (SVD-DWT) techniques. BDS is dedicated to improve the low quality of MRI images with preservation of the brightness level and the edge details from degradation and without added artifacts or noise. These features are essential in CE approaches for a better lesion recognition. A modified version of BDS called MBDS is also implemented in the second part of this paper wherein we have proposed a new method for computing the correction factor. Indeed, with the use of the new correction factor, the entropy has been increased and the contrast is greatly enhanced. MBDS is specially dedicated for very low contrast MRI images. The experimental results proved the effectiveness of developed methods in improving low contrast of MRI images with preservation of brightness level and edge information. Moreover, performances of both proposed BDS and MBDS algorithms exceeded conventional CE methods.


Assuntos
Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Imageamento por Ressonância Magnética/métodos , Encéfalo , Algoritmos , Cabeça , Aumento da Imagem
15.
Brain ; 146(4): 1496-1510, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-36073231

RESUMO

The protein phosphatase 2A complex (PP2A), the major Ser/Thr phosphatase in the brain, is involved in a number of signalling pathways and functions, including the regulation of crucial proteins for neurodegeneration, such as alpha-synuclein, tau and LRRK2. Here, we report the identification of variants in the PTPA/PPP2R4 gene, encoding a major PP2A activator, in two families with early-onset parkinsonism and intellectual disability. We carried out clinical studies and genetic analyses, including genome-wide linkage analysis, whole-exome sequencing, and Sanger sequencing of candidate variants. We next performed functional studies on the disease-associated variants in cultured cells and knock-down of ptpa in Drosophila melanogaster. We first identified a homozygous PTPA variant, c.893T>G (p.Met298Arg), in patients from a South African family with early-onset parkinsonism and intellectual disability. Screening of a large series of additional families yielded a second homozygous variant, c.512C>A (p.Ala171Asp), in a Libyan family with a similar phenotype. Both variants co-segregate with disease in the respective families. The affected subjects display juvenile-onset parkinsonism and intellectual disability. The motor symptoms were responsive to treatment with levodopa and deep brain stimulation of the subthalamic nucleus. In overexpression studies, both the PTPA p.Ala171Asp and p.Met298Arg variants were associated with decreased PTPA RNA stability and decreased PTPA protein levels; the p.Ala171Asp variant additionally displayed decreased PTPA protein stability. Crucially, expression of both variants was associated with decreased PP2A complex levels and impaired PP2A phosphatase activation. PTPA orthologue knock-down in Drosophila neurons induced a significant impairment of locomotion in the climbing test. This defect was age-dependent and fully reversed by L-DOPA treatment. We conclude that bi-allelic missense PTPA variants associated with impaired activation of the PP2A phosphatase cause autosomal recessive early-onset parkinsonism with intellectual disability. Our findings might also provide new insights for understanding the role of the PP2A complex in the pathogenesis of more common forms of neurodegeneration.


Assuntos
Deficiência Intelectual , Transtornos Parkinsonianos , Animais , Encéfalo/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Deficiência Intelectual/genética , Transtornos Parkinsonianos/genética , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Fosfoproteínas Fosfatases/metabolismo
16.
Acta Myol ; 42(4): 106-112, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38406381

RESUMO

Fukutin-related protein (FKRP) mutations cause a broad spectrum of muscular dystrophies, from a relatively mild limb-girdle muscular dystrophy type 9 (LGMDR9) to severe congenital muscular dystrophy (CMD). This study aims to report two siblings belonging to a non-consanguineous Tunisian family harboring a novel compound heterozygous FKRP variant and presenting a mild LGDMR9 phenotype. For mutation screening, massive parallel sequencing was performed, followed by Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA) to validate the existence of the discovered variants. The absence of alpha-dystroglycan was determined by immunohistochemistry. Brain and thigh magnetic resonance imaging (MRI) were performed to detect thigh and brain abnormalities. The two siblings had a late age at onset and clinical examination showed that the pelvic girdles had a predominantly proximal and symmetrical distribution of weakness without cardiac or respiratory involvement. They both had a modified Gardner-Medwin Walton Scale mGMWS grade of 4 and a modified Rankin Scale (mRS) score of 1. The DNA sequencing revealed a novel deletion of exons 2 and 3 in one allele and a missense mutation c.1364C > A, which has been reported to be responsible for congenital muscular dystrophy and mental retardation on the second allele. The simultaneous presence of the two variations in the two cases suggests that the variants segregate with the pathophysiology.


Assuntos
Distrofia Muscular do Cíngulo dos Membros , Distrofias Musculares , Humanos , Músculo Esquelético/patologia , Distrofias Musculares/diagnóstico , Distrofias Musculares/genética , Distrofias Musculares/congênito , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação , Pentosiltransferases/genética , Pentosiltransferases/metabolismo , Fenótipo , Proteínas/genética , Proteínas/metabolismo
17.
Neurol Res ; 44(12): 1074-1085, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36074940

RESUMO

AIM: To investigate the gender difference effect on postural balance, functional mobility, and fall risk after performing a fatiguing task in adults with multiple sclerosis (MS). METHODS: Eleven women (30.91 ± 8.19 years) and seven men (30.29 ± 7.99 years) with relapsing-remitting MS performed a fatiguing task: three sets of the Five-repetition Sit-To-Stand Test (5-STST) were performed before and after the six-minute WalkTest (6MWT). Bipedal postural balance in eyes open and eyes closed conditions were assessed prefatigue (T0) and postfatigue (T3) using a force platform. Unipedal balance, functional mobility (Timed Up and Go Test), fall risk (Four Square Step Test) and fatigue [Visual Analogue Scale of Fatigue (VASF)] were assessed at T0 and T3. Heart rate (HR) and Rating of Perceived Exertion (RPE) were recorded before (only for HR), during and after the fatiguing task. RESULTS: Compared to women, men showed an impairment of posturographic parameters [mean center of pressure (CoP) velocity (CoPVm) in both conditions (p < 0.05); CoP sway area (CoPAr) in both conditions (p < 0.01)], unipedal balance on the dominant leg (p <0.001), mobility (p<0.001) and an increased fall risk (p < 0.05). No gender differences were observed in 6MWT, 5-STST, HR, RPE, and VASF. CONCLUSION: This preliminary study showed that fatiguing task negatively affected postural control, mobility and fall risk only in men. These gender differences were inconclusive but could be taken into account in postural balance rehabilitation programs for MS persons.


Assuntos
Esclerose Múltipla , Feminino , Humanos , Esclerose Múltipla/complicações , Equilíbrio Postural , Estudos de Tempo e Movimento
18.
Sci Rep ; 12(1): 16425, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180495

RESUMO

In multiple sclerosis (MS) disease, the importance of the intrathecal B cell response classically revealed as IgG oligoclonal bands (OCB) in cerebrospinal fluid (CSF) was reaffirmed again in the recently revised diagnostic criteria. We aimed to optimize Laboratory investigation by testing the performance of new B cell-related molecules in CSF (Ig free light chains (FLCκ and λ) and CXCL13 (B-Cell Attracting chemokine1)) for MS diagnosis. 320 paired (CSF-serum) samples were collected from 160 patients with MS (n = 82) and non-MS diseases (n = 78). All patients benefited from IgG index determination, OCB detection, CSF CXCL13 and FLC (κ and λ) measurement in CSF and serum for metrics calculation (κ/λ ratio, FLC-related indexes, and κFLC-intrathecal fraction (IF)). CXCL13 and FLC metrics in CSF were higher in patients with MS and positive OCB. As expected, κFLC metrics-in particular, κFLC index and κFLC IF-had the highest accuracy for MS diagnosis. κ index showed the best performance (sensitivity 83% and specificity 91.7%) at a cut-off of 14.9. Most of the FLC-related parameters were positively correlated with IgG index and the level of CXCL13. In conclusion, the quantitative, standardizable, and technically simple CSF FLCκ metrics seem to be reliable for MS diagnosis, but could not replace OCB detection. CXCL13 appears to be an effective parameter reflecting the intrathecal B cell response. An optimized way for CSF testing combining the conventional and the new B cell-related parameters is proposed in this study.


Assuntos
Esclerose Múltipla , Bandas Oligoclonais , Biomarcadores , Humanos , Imunoglobulina G/líquido cefalorraquidiano , Cadeias Leves de Imunoglobulina , Cadeias kappa de Imunoglobulina , Bandas Oligoclonais/líquido cefalorraquidiano
19.
Int J Neurosci ; : 1-11, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35708140

RESUMO

AIM: To assess the safety and the effect of a nocturnal melatonin (MEL) ingestion on postural balance, functional mobility and fall risk the following morning in adults with multiple sclerosis (MS). METHODS: Fourteen adults with relapsing-remitting MS (RR-MS) (28.36 ± 6.81 years) were evaluated before and after nocturnal ingestion of MEL (6 mg) or placebo (PLA). Evaluations included a posturographic test of static bipedal postural balance with dual-task in eyes open (EO) and eyes closed conditions, and a clinical test of unipedal balance. The physical performance tests were: Timed Up and Go test (TUGT) (mobility), Four Square Step Test (FSST) (fall risk), and Timed 25-foot walk test (T25FWT) (walking speed). Cognitive performance [Montreal Cognitive Assessment (MoCA) and Simple Reaction Time (SRT) tests] and sleep quality [Spiegel's sleep questionnaire (SSQ)] were also assessed. RESULTS: In EO condition, MEL decreased the posturographic parameters [center of pressure (CoP) sway area (CoPAr), CoP path length (CoPL) and CoPL in the mediolateral axis (CoPLX)] more than PLA by 15.82% (p = 0.0006), 12.48% (p = 0.0004) and 14.25% (p = 0.0002), respectively. Durations of TUGT and FSST decreased following MEL session more than the PLA one by 14.52% (p = 0.017) and 19.85% (p = 0.0006), respectively. MEL increased the unipedal stance time, SSQ and MoCA scores more than PLA by 49.81% (p = 0.04), 32.21% (p = 0.004) and 11.87% (p = 0.008), respectively. CONCLUSION: This pilot study showed that acute nocturnal MEL ingestion seems to be safe for enhancing postural balance, fun mobility and fall risk in RR-MS adults probably through improving sleep quality and cognitive function.

20.
Ann Med Surg (Lond) ; 76: 103556, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35495383

RESUMO

Introduction: and importance: Papillary Thyroid carcinoma (PTC) is the most common endocrine malignancy and accounts for 1-2% of all cancer cases. Second malignancies in women diagnosed with thyroid cancer are of concern given the young average age at diagnosis. The concurrent occurrence of thyroid cancer and malignant brain tumor such as glioblastoma (GBM) was rarely seen and reported. However, the simultaneous association of these 2 conditions, namely PTC and GBM, in a neurofibromatosis type 1 (NF1) patient, has never been reported before in the literature. Case presentation: The authors report the first case of an extremely rare association combining papillary thyroid carcinoma, glioblastoma, and a neurofibromatosis 1 in a 34-year-old female patient with primary generalized tonic-clonic seizures. Clinical discussion: NF1 can be associated with PTC and GBM independently. In this current case, NF1 was accompanied by both PTC and GBM. With the exception of the present case, to our knowledge, there has been no previous case report in the literature in which these 3 entities were associated. The reason for the rarity of this combination of these neoplasms in patients with NF1 remains not clear, but it may be explained by the low incidence of combined occurrence of PTC and GBM. Conclusion: This is the first reported extremely rare coexistence of GBM and PTC in a female NF1 patient. Further genetic investigations could improve our understanding of this combination and change our therapeutic approaches.

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