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1.
Neuropathology ; 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38972833

RESUMO

The first postmortem neuropathological findings of a hemiparkinsonism and hemiatrophy (HPHA) patient are presented. A 50-year-old man developed resting tremors affecting the right hand and leg, followed by mild clumsiness of the right hand. On examination, he exhibited muscle atrophy of the right leg extremity, accompanied by right-sided parkinsonism. Brain magnetic resonance imaging was normal. Based on the clinical and radiological findings, HPHA syndrome was diagnosed, showing a good response to L-DOPA. He gradually developed muscular atrophy of the right distal upper extremity. Thirteen years after the onset of the disease, left-sided parkinsonism appeared. The patient died of Trousseau's syndrome associated with a rapidly emerging pancreatic tumor. The total duration of the disease was 14 years. Neuropathologically, the substantia nigra showed markedly left-predominant neuronal loss, along with almost symmetrical Lewy body (LB) pathology. These findings indicated that the patient originally had fewer neurons in the left substantia nigra than in the right, probably caused by congenital or childhood cerebral injury, followed by the development of unilateral parkinsonism due to the progression of LB pathology. Despite our extensive neuropathological analysis, we could not specify the etiology or anatomical substrate responsible for the development of right upper and lower extremity atrophy. Further clinicopathological studies are needed to elucidate the pathoanatomical areas causing hemiparkinsonism and hemiatrophy.

2.
BMC Neurol ; 21(1): 51, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33535984

RESUMO

BACKGROUND: There is no established pathogenesis of hemiparkinsonism-hemiatrophy syndrome (HPHA), and the varied clinical presentations have been reported in several case studies. To the best of our knowledge, the present report describes the first case of HPHA with unusual brain imaging findings. CASE PRESENTATION: A 20-year-old man presented with a 6-month history of weakness and clumsiness in his right limbs. He showed right-sided parkinsonism with dystonic hand posture; however, body asymmetry was not noted. Brain imaging revealed hemiatrophy of the left hemisphere subcortical structures and brainstem, and iron deposition in the left globus pallidus and substantia nigra. In addition, dopamine transporter imaging demonstrated normal presynaptic dopaminergic function. The patient was treated with levodopa, which had little to no effect. CONCLUSIONS: This case demonstrates the unique imaging characteristics of HPHA associated with widespread brain hemiatrophy and iron deposition. Further studies are needed to elucidate the diagnostic criteria for this heterogeneous syndrome.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/patologia , Antiparkinsonianos/uso terapêutico , Atrofia/patologia , Lateralidade Funcional , Humanos , Ferro , Levodopa/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Transtornos Parkinsonianos/tratamento farmacológico , Adulto Jovem
3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(3): 531-533, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34018377

RESUMO

The patient, a 25-year-old woman, was seen at our hospital 6 years ago, complaining of weakness and stiffness in the left side of the body and left limbs for 1 + years. Physical examination revealed atrophy of the upper and lower limbs on the left side. Neurological examination showed increased muscle tone in the left-side body and limbs, bradykinesia, decreased muscle strength in the left-side body and limbs, and positive Hoffman's sign in the left limbs. Laboratory tests, including alpha fetoprotein (AFP), ß-human chorionic gonadotropin (HCG) and cerebrospinal fluid examination, did not reveal any abnormal results. Head MRI showed right cerebral hemiatrophy. Head and neck CT angiography did not show obvious abnormality. According to the medical history and examination results, diagnosis of hemiparkinsonism-hemiatrophy syndrome was made. Through close follow-up for 6 years, we noticed that the parkinsonism remained unilateral and stable, and the contralateral cerebral hemiatrophy did not show obvious progress. However, brain perfusion MRI showed hypoperfusion of the right basal ganglia. The discovery of hypoperfusion in the basal ganglia may help explore the etiology of hemiparkinsonism-hemiatrophy syndrome.


Assuntos
Transtornos Parkinsonianos , Adulto , Atrofia , Gânglios da Base/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Transtornos Parkinsonianos/complicações , Transtornos Parkinsonianos/diagnóstico por imagem
4.
Neurochem Res ; 43(5): 1086-1095, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29616443

RESUMO

Epidemiological studies indicate that a higher plasma level of uric acid (UA) associates with the reduced risk of Parkinson's disease (PD). To confirm the role of UA as a biomarker for PD, we evaluated changes in the serum UA level in the 6-hydroxydopamine (6-OHDA)-induced hemiparkinsonism in rat. For this purpose, 6-OHDA was administered in the medial forebrain bundle by stereotaxic surgery. According to the apomorphine-induced rotational test, the increased intensity of behavioral symptoms as a function of time was associated with the further reduction of UA level. On the other hand, the level of UA increased in the midbrain of the injured hemisphere. The level of reduction in the serum UA level of rats with severe and moderate symptoms was significantly higher than that of rats with mild symptoms. The immunohistofluorescence and biochemical analyses showed that the serum UA level was also correlated with the death of tyrosine hydroxylase (TH)-positive neurons in the substantia nigra pars compacta (SNc), reduced level of striatal dopamine, and severity of oxidative stress in the midbrain. The rats with mild symptoms also showed a significant decrease in TH-positive neurons and striatal dopamine level. These findings suggest a positive correlation between the level of reduction in the serum urate level and severity of 6-OHDA-induced Parkinsonism. In addition, our findings indicated that UA had no marked neuroprotective effects, at least at concentrations obtained in this study. On the other hand, UA was introduced as a biomarker for PD, as a significant decline was observed in the serum UA level of rats with mild behavioral symptoms but with significant dopaminergic cell death in the SNc.


Assuntos
Oxidopamina , Doença de Parkinson Secundária/sangue , Doença de Parkinson Secundária/induzido quimicamente , Ácido Úrico/sangue , Animais , Apomorfina/farmacologia , Biomarcadores/sangue , Morte Celular , Dopamina/metabolismo , Agonistas de Dopamina/farmacologia , Masculino , Neurônios , Estresse Oxidativo , Valor Preditivo dos Testes , Ratos , Ratos Wistar , Substância Negra/patologia , Tirosina 3-Mono-Oxigenase
5.
J Stroke Cerebrovasc Dis ; 25(2): e20-1, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26639402

RESUMO

There are different etiologies of hemiparkinsonism. A few patients with hemiparkinsonism secondary to infarction in the contralateral substantia nigra have been reported in the literature, and only one of these patients presented with pure hemiparkinsonism. This paper reports the unusual case of a patient presenting with pure hemiparkinsonism secondary to a lacunar stroke in the substania nigra. A 66-year-old man who presented with a 5-year history of left-sided hemiparkinsonism manifested by tremor, rigidity, and bradykinesia located mainly on the upper extremity. Magnetic resonance imaging of the brain revealed a lacunar infarct located in the right substantia nigra. Patients experiencing sudden hemiparkinsonism should be investigated to rule out any abnormality in the contralateral substantia nigra. This case points to the significance of neuroimaging in the evaluation of unilateral parkinsonism.


Assuntos
Transtornos Parkinsonianos/etiologia , Acidente Vascular Cerebral Lacunar/complicações , Substância Negra/patologia , Idoso , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos Parkinsonianos/patologia , Acidente Vascular Cerebral Lacunar/patologia
6.
J Neurosurg Case Lessons ; 5(6)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36748751

RESUMO

BACKGROUND: The etiologies of parkinsonism are diverse. A possible and rare cause of hemiparkinsonism is mechanical compression of the basal ganglia and its connecting white matter tracts. The authors present a case of hemiparkinsonism caused by a lateral sphenoid wing meningioma, discuss the underlying pathophysiology based on tractography, and systematically review the existing literature. OBSERVATIONS: A 59-year-old female was referred for a left-sided tremor of the hand, accompanied by a cogwheel rigidity of the left arm. Symptomatology appeared 1 year earlier and worsened in the previous 6 months, finally also showing involvement of the left leg. Magnetic resonance imaging (MRI) showed a space-occupying suspected meningioma originating from the right lateral sphenoid wing and compressing the ipsilateral striatum. Tractography studies contributed to elucidate the underlying pathophysiology. Resection of the meningioma could be performed without complications. At the 4-month follow-up, the patient's hemiparkinsonism had completely recovered. LESSONS: An intracranial space-occupying lesion may be a rare cause of hemiparkinsonism. In new-onset parkinsonism, especially if a secondary form is suspected, brain MRI should be performed promptly to avoid misdiagnosis and treatment. Tractography studies help understand the underlying pathophysiology. After surgical decompression of the affected structures, symptoms can recover completely.

7.
Neurotox Res ; 41(2): 187-200, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36662412

RESUMO

It is now well recognized that a bidirectional relationship between gut microbiota and the brain, referred to as the gut-brain axis, plays a prominent role in maintaining homeostasis and that a disruption in this axis can result in neuroinflammatory response and neurological disorders such as Parkinson's disease (PD). The protective action of probiotics such as Bifidobacterium animalis ssp. lactis Bb12 and Lactobacillus rhamnosus GG in various animal models of PD has been reported. Therefore, in this study, we used an inflammatory model of PD to assess the effects of a combination of these two probiotics (Microbiot®) on motor behavior as well as on the response of microglia, including microglia morphology, to gain a better understanding of their mechanism of action. Microbiot® (300 µL) was administered orally once daily for 15 days in a lipopolysaccharide-induced PD model using male Wistar rats. Although LPS-induced motor asymmetry in cylinder test was not affected by Microbiot®, impairment of motor coordination in the narrow-beam test was significantly reduced by this probiotic. Moreover, Microbiot® treatment reduced microglial activation suggesting an anti-inflammatory effect. While further mechanistic investigation of Microbiot® in neurodegenerative diseases is warranted, our results support the potential utility of probiotics in PD.


Assuntos
Bifidobacterium animalis , Lacticaseibacillus rhamnosus , Doença de Parkinson , Probióticos , Ratos , Masculino , Animais , Doença de Parkinson/tratamento farmacológico , Ratos Wistar , Probióticos/farmacologia , Probióticos/uso terapêutico , Lipopolissacarídeos/toxicidade
8.
Parkinsonism Relat Disord ; 110: 105402, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37084521

RESUMO

Despite various neurologic symptoms of Poland syndrome (PS), parkinsonism was never reported in PS, and the response to the treatment of parkinsonism was not studied before. We report a case of ipsilateral parkinsonism in PS, similar to hemiatrophy-hemiparkinsonism, with a good response to levodopa and subthalamic deep brain stimulation.


Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Síndrome de Poland , Humanos , Síndrome de Poland/complicações , Síndrome de Poland/diagnóstico por imagem , Doença de Parkinson/diagnóstico , Atrofia , Transtornos Parkinsonianos/complicações , Transtornos Parkinsonianos/diagnóstico por imagem , Levodopa
9.
Iran J Basic Med Sci ; 25(11): 1357-1363, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36474564

RESUMO

Objectives: Parkinson's disease (PD) is a neurodegenerative disorder involving the central nervous system associated with motor and non-motor impairments. Betulinic acid (BA) is a natural substance considered an antioxidative agent. This study aimed to investigate the therapeutic potential of BA on motor dysfunctions and globus pallidus (GP) local EEG power in a 6-hydroxydopamine (6-OHDA)-induced rat model of hemiparkinsonism. Materials and Methods: Adult Wistar rats were categorized into different groups, containing; Sham, PD, and treated groups including different doses of BA (0.5, 5, and 10 mg/kg, IP), and L-dopa (20 mg/kg, PO, as positive control). The lesion was induced in the right medial forebrain bundle by injection of 6-OHDA (20 µg/kg). The treatment was begun just after the approved rotational test induced by apomorphine, 14 days after 6-OHDA administration. Motor behaviors such as catalepsy and stride-length and non-motor responses, including GP local EEG, were then assessed. Also, the levels of GSH, catalase, and concentration of dopamine in the brain tissue were measured. Results: Treatment of hemiparkinsonian rats with BA significantly improved catalepsy and stride-length (P<0.001 and P<0.01, respectively) and GP frequency bands' powers (P<0.001). Moreover, the activities of GSH (P<0.001), catalase (P<0.001), and the concentration of dopamine (P<0.001) in the brain were increased. Conclusion: Current results proved the potent ability of BA to scavenge free radicals and to remove oxidative agents in the brain tissue. This natural product could be considered a possible therapeutic compound for motor and non-motor disorders in PD.

10.
Med Biol Eng Comput ; 60(10): 2995-3007, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36018532

RESUMO

Computerized techniques for image analysis are critical for progress in cell biology. The complexity of the data in current methods eliminates the need for manual image analysis and usually requires the application of multiple algorithms sequentially to the images. Our aim was to develop a software for immunohistochemical analysis of brain dopaminergic neurons combining several computational approaches to automatically analyze and quantify their number in the substantia nigra after a neurotoxic injury. For this purpose, we used a Parkinson's disease animal model to test our application. The dopaminergic neurotoxin, 6-hydroxydopamine, was administered in adult male rats to damage dopaminergic neurons in substantia nigra and to induce hemiparkinsonism. The lesion was corroborated by behavioral evaluation in response to apomorphine and amphetamine. The animals were euthanized and their brains processed for tyrosine hydroxylase immunohistochemistry for dopamine neuron identification. Neurons positive for tyrosine hydroxylase were evaluated in substantia nigra by light microscopy. The images were used to show quantification applicability. To test our software counting accuracy and validity, automatic dopamine neuron number was correlated with the data obtained by three independent observers. Several parameters were used to depict neuronal function in dataset images from control and lesioned brains. In conclusion, we could perform an automated quantification of dopaminergic neurons and corroborate the validity and accuracy of a freely available software.


Assuntos
Neurônios Dopaminérgicos , Tirosina 3-Mono-Oxigenase , Animais , Neurônios Dopaminérgicos/metabolismo , Masculino , Oxidopamina/toxicidade , Ratos , Software , Substância Negra/metabolismo , Substância Negra/patologia , Tirosina 3-Mono-Oxigenase/metabolismo
11.
Intern Med ; 60(2): 309-313, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32963161

RESUMO

A 24-year-old female patient was admitted for a right frontal intracranial hematoma with an uncal herniation due to a ruptured arteriovenous malformation and therefore underwent emergency surgery. Neuroimaging revealed left-sided midbrain notching against the tentorium, indicating Kernohan's notch phenomenon. She denied experiencing any short-term neurological deficits but right-sided delayed hemiparkinsonism developed 18 months later. Dopamine transporter tracer uptake was severely reduced in the left striatum, suggesting nigrostriatal degeneration secondary to Kernohan's notch. Uncal herniations are potentially fatal, but surgery can save the patient's life and improve the functional outcomes. Clinicians should therefore be aware of delayed hemiparkinsonism as a rare complication of Kernohan's notch phenomenon.


Assuntos
Malformações Arteriovenosas , Imageamento por Ressonância Magnética , Adulto , Feminino , Humanos , Mesencéfalo , Adulto Jovem
12.
Behav Brain Res ; 397: 112957, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33038348

RESUMO

We investigated the prodromal alterations of local sleep, particularly the motor cortical and hippocampal sleep, along with spontaneous locomotor activity in the rat models of Parkinson's disease (PD). We performed our experiments in adult, male Wistar rats, chronically implanted for sleep recording and divided into four experimental groups: the control (implanted controls), the bilateral pedunculopontine tegmental nucleus (PPT) lesions (PD cholinopathy), the unilateral substantia nigra pars compacta (SNpc) lesions (hemiparkinsonism) and the unilateral SNpc/bilateral PPT lesions (hemiparkinsonism with PD cholinopathy). We followed their sleep, basal locomotor activity and spatial habituation for 14 days following the surgical procedures. Severe prodromal local sleep disturbances in the hemiparkinsonian rats were expressed as sleep fragmentation and distinct local NREM/REM EEG microstructure alterations in both the motor cortex and the hippocampus. Alongside the state-unrelated role of the dopaminergic control of theta oscillations and NREM/REM related sigma and beta oscillations, we demonstrated that the REM neurochemical regulatory substrate is particularly important in the dopaminergic control of beta oscillations. In addition, hippocampal prodromal sleep disorders in the hemiparkinsonian rats were expressed as NREM/REM fragmentation and the opposite impact of dopaminergic versus cholinergic control of the NREM delta and beta oscillation amplitudes in the hippocampus, likewise in the motor cortex versus the hippocampus. All these distinct prodromal local sleep disorders and the dopaminergic vs. cholinergic impact on NREM/REM EEG microstructure alterations are of fundamental importance for the further development and follow-up of PD-modifying therapies, and for the identification of patients who are at risk of developing PD.


Assuntos
Ondas Encefálicas/fisiologia , Hipocampo/fisiopatologia , Locomoção/fisiologia , Córtex Motor/fisiopatologia , Transtornos Parkinsonianos/fisiopatologia , Sintomas Prodrômicos , Fases do Sono/fisiologia , Transtornos do Sono-Vigília/fisiopatologia , Animais , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Eletrocorticografia , Eletromiografia , Masculino , Doença de Parkinson/complicações , Doença de Parkinson/fisiopatologia , Transtornos Parkinsonianos/complicações , Ratos , Ratos Wistar , Transtornos do Sono-Vigília/etiologia
13.
J Neurol ; 267(4): 1127-1136, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31902006

RESUMO

INTRODUCTION: Impulsive compulsive behaviors (ICBs) in Parkinson's disease (PD) are debilitating disorders of repetitive, excessive, and compulsive nature affecting up to one third of PD patients. Objectives are to address clinical, psychiatric, and cognitive characteristics of ICBs and to define risk factors in PD patients in the initial motor stage, followed up for 5 years. METHODS: We analyzed 106 consecutive PD outpatients at Hoehn and Yahr disease stage 1 and 125 healthy controls. The participants were assessed for the presence of any ICB using the current clinical criteria and underwent comprehensive clinical, psychiatric, and neuropsychological evaluations. The patients completed the same protocol at Years 1, 2, 3, and 5. RESULTS: ICBs were present in 21 (19.8%) PD patients and 13 (10.4%) healthy controls at baseline. Prevalence of ICBs increased to 29.2% at Year 5, significantly after Year 2. Multiple ICBs were present in 4,7% and 61.9% of PD-ICBs at the baseline and Year 5, respectively. ICBs resolved in 30% of cases (most often compulsive eating). Dopamine agonist treatment at the baseline carried five times higher risk of having or developing ICB(s) anytime during follow-up. We identified risk factors for compulsive eating (dopamine agonist treatment at baseline), hypersexuality (males), compulsive buying (depression and younger age), and punding (younger age and higher levodopa dose at baseline). Significant interaction of rate of motor progression and ICB diagnosis was shown. CONCLUSIONS: PD patients showed increasing frequency of most ICBs during the 5-year follow-up. Specific risk factors were identified for different types of ICBs.


Assuntos
Comportamento Compulsivo/etiologia , Comportamento Compulsivo/fisiopatologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/etiologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/fisiopatologia , Dopaminérgicos/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Fatores Etários , Idoso , Comportamento Compulsivo/induzido quimicamente , Transtornos Disruptivos, de Controle do Impulso e da Conduta/induzido quimicamente , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais
14.
Front Neurosci ; 14: 64, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32116511

RESUMO

Hemiparkinsonism-hemiatrophy syndrome (HPHA) and hemidystonia-hemiatrophy syndrome (HDHA) are rare movement disorders composed of hemidystonia or hemiparkinsonism that present with unilateral limb, face, trunk, or cerebral hemiatrophy and mostly occur following head trauma or postanoxic events. However, relatively little is known about the pathogenesis of these conditions. In our case series, we present three HPHA patients and one HDHA patient who underwent detailed neuropsychological, radiological, motor, and non-motor functional assessments with a mean follow-up of 2 years. We followed two patients who showed differences in their progression for more than 2 years: one barely progressed with no treatment, and the other exhibited levodopa-induce dyskinesia (LID) and definitive progression while receiving multiple adjunctive therapies. In addition, we performed positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) and 18F-dihydroxyphenylalanine (DOPA) in one HPHA patient who showed bilaterally symmetrical uptake of FDG with no significant increase or decrease in the cerebral hemispheres, including the striatum, but exhibited a significant reduction in the uptake of 18F-DOPA in the contralateral posterior striatum. In this study, we followed HPHA patients who showed different disease courses to explore the clinical characteristics and pathogenesis of HPHA and HDHA and illustrate the clinical heterogeneity of these diseases.

15.
Neurosci Res ; 154: 56-59, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31103423

RESUMO

Unilateral injection of 6-hydroxydopamine (6-OHDA) is commonly used to generate a rodent model of Parkinson's disease (PD). Although motor deficits of the lower extremities represent one of the major clinical symptoms in PD patients, validated tests for assessing motor impairments of the hind limb in 6-OHDA mice are currently unavailable. We here report the video-based assessments of the asymmetric use of hind limbs in 6-OHDA mice. A significantly decreased number of spontaneous hind limb stepping was observed in the contralateral-to-lesioned side, and was dose dependently reversed by levodopa, suggesting that it could be utilized for screening PD therapeutics.


Assuntos
Modelos Animais de Doenças , Marcha/efeitos dos fármacos , Transtornos Parkinsonianos/induzido quimicamente , Animais , Corpo Estriado/metabolismo , Membro Posterior , Levodopa/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxidopamina , Tirosina 3-Mono-Oxigenase/metabolismo
16.
Neurosci Lett ; 739: 135443, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33141067

RESUMO

Parkinson's Disease (PD) patients undergoing subthalamic nucleus deep brain stimulation (STN-DBS) therapy can reduce levodopa equivalent daily dose (LEDD) by approximately 50 %, leading to less symptoms of dyskinesia. The underlying mechanisms contributing to this reduction remain unclear, but studies posit that STN-DBS may increase striatal dopamine levels by exciting remaining dopaminergic cells in the substantia nigra pars compacta (SNc). Yet, no direct evidence has shown how SNc neuronal activity responds during STN-DBS in PD. Here, we use a hemiparkinsonian rat model of PD and employ in vivo electrophysiology to examine the effects of STN-DBS on SNc neuronal spiking activity. We found that 43 % of SNc neurons in naïve rats reduced their spiking frequency to 29.8 ± 18.5 % of baseline (p = 0.010). In hemiparkinsonian rats, a higher number of SNc neurons (88 % of recorded cells) decreased spiking frequency to 61.6 ± 4.4 % of baseline (p = 0.030). We also noted that 43 % of SNc neurons in naïve rats increased spiking frequency from 0.2 ± 0.0 Hz at baseline to 1.8 ± 0.3 Hz during stimulation, but only 1 SNc neuron from 1 hemiparkinsonian rat increased its spiking frequency by 12 % during STN-DBS. Overall, STN-DBS decreased spike frequency in the majority of recorded SNc neurons in a rat model of PD. Less homogenous responsiveness in directionality in SNc neurons during STN-DBS was seen in naive rats. Plausibly, poly-synaptic network signaling from STN-DBS may underlie these changes in SNc spike frequencies.


Assuntos
Potenciais de Ação , Neurônios/fisiologia , Transtornos Parkinsonianos/fisiopatologia , Parte Compacta da Substância Negra/fisiopatologia , Núcleo Subtalâmico/fisiopatologia , Animais , Modelos Animais de Doenças , Estimulação Elétrica , Masculino , Doença de Parkinson/fisiopatologia , Ratos Sprague-Dawley
17.
Brain Res ; 1742: 146888, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32439342

RESUMO

OBJECTIVE: The motor dysfunctions always affect hemi-body first in Parkinson's disease (PD). However, the interhemispheric relationships in patients with only unilateral motor impairment were barely known to date. We aimed to investigate the interhemispheric functions using resting-state functional Magnetic resonance imaging (RS-fMRI) for further understanding the pathogenesis of PD. METHODS: Forty-three unilateral-symptomatic PD patients (UPD, Hoehn-Yahr staging scale, H-Y: 1-1.5), and 54 age-, gender-, education-matched normal controls (NC) were recruited. All subjects underwent MRI scanning and clinical evaluations. The interhemispheric coordination (Voxel-Mirrored Homotopic Connectivity, VMHC) and hemispheric dominance pattern (laterality index of eigenvector centrality mapping, LI-ECM) were calculated. Afterwards, correlation analyses and receiver operating characteristic (ROC) curve analysis were employed. RESULTS: Compared with NC, UPD group showed significantly decreased VMHC in bilateral sensorimotor regions which was negatively correlated with the motor score. Furthermore, at the cut-off homotopic connectivity of 0.604, statistically significant ability of VMHC to discriminate UPD from NC with area under ROC curve (AUC) = 0.759, p < 0.001; specificity = 74.4%; sensitivity = 68.5% was observed. No difference was detected in UPD patients as for ECM and LI-ECM. CONCLUSIONS: The disrupted interhemispheric coordination in bilateral sensorimotor regions may have significant implications for elucidating the mechanisms underlying the hemiparkinsonism and enabling the uncovering of complex mechanisms of PD.


Assuntos
Lateralidade Funcional/fisiologia , Atividade Motora/fisiologia , Transtornos Parkinsonianos/fisiopatologia , Adulto , Idoso , Encéfalo/patologia , Mapeamento Encefálico/métodos , China , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/metabolismo , Descanso
18.
Comput Biol Med ; 115: 103482, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31614228

RESUMO

To reveal the best choice of algorithm for parvalbumin-immunostained images of the hippocampal gyrus dentatus in two distinct rat models of Parkinson's disease (PD), particularly in terms of extracting the crucial information from the image, we tested whether the impact of experimentally induced dopaminergic (hemiparkinsonism) vs. cholinergic (PD cholinopathy) innervation impairment on the parvalbumin stained GABA interneurons could be detected using two separate algorithms, the fractal box-count and the gray-level co-occurrence matrix analysis (GLCM) algorithms. For the texture and fractal analysis of the hippocampal gyrus dentatus images, we used.tif images from three experimental groups of adult male Wistar rats: control rats, rats with Parkinson disease (PD) cholinergic neuropathology (with a PPT lesion), and hemiparkinsonian rats (with a SNpc lesion). For the suprapyramidal layer of the gyrus dentatus ASM and Entropy differentiated the images of the SNpc lesion versus the images of the control and the PPT lesion subjects, with significantly higher ASM and lower Entropy, indicating the homogenization of the images and their lower gray-level complexity. The infrapyramidal images of the SNpc group were differentiated versus the images from the control and PPT groups in terms of all the GLCM parameters: they showed lower mean Entropy and Contrast and higher ASM, Correlation and IDM. These results strongly suggest a rise in the uniformity, homogeneity and orderliness in the gray-levels of images from the SNpc group. Our results indicate that GLCM analysis is a more sensitive tool than fractal analysis for the detection of increased dendritic arborization in histological images.


Assuntos
Giro Denteado , Processamento de Imagem Assistida por Computador , Interneurônios , Doença de Parkinson Secundária , Parvalbuminas/metabolismo , Animais , Giro Denteado/metabolismo , Giro Denteado/patologia , Interneurônios/metabolismo , Interneurônios/patologia , Masculino , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson Secundária/patologia , Ratos , Ratos Wistar , Coloração e Rotulagem
19.
Mov Disord Clin Pract ; 5(1): 103-104, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30868100

RESUMO

A 33 year-old male presented with right upper limb rest tremor that disappeared on action, posture associated with bradykinesia, and rigidity of right upper and lower limbs (Video S1). Patient also presented right-sided pyramidal weakness (grade 4), hyperreflexia, extensor plantar response, and hemihypesthesia. Skull X-ray and computed tomography (CT) of the brain showed several metal pellets producing multiple artifacts (Fig. 1A,B). Only one pellet settled in brain parenchyma (left midbrain), while other pellets settled in the skull bone (Fig. 1A). Transcranial sonography (TCS) was performed, confirming that the midbrain pellet was placed within the left substantia nigra (Fig. 1C). Levodopa challenge test was conducted, showing no improvement (pre- and post-l-dopa motor UPDRS were 21 and 20, respectively). A further chronic trial of l-dopa (for 3 months) also proved negative. Biperiden and propranolol were also tried with negative results. Figure 1Computed tomography (CT) of the brain and X-ray skull showed several pellets that produced multiple streak artifacts (Fig. 1A,B). Only one pellet rested in the brain parenchyma, the left (contralateral) midbrain as detected by CT (Fig. 1A), and transcranial sonography (Esaote MyLab Five, Providian, Italy) via temporal window (Fig. 1C). Abbreviations: SN, substantia nigra.Hemiparkinsonism has been previously reported secondary to midbrain lesions.1, 2 To the best of our knowledge, movement disorders (secondary to brain injuries) related to bullet fragments have been scantly reported. In one reported case, hemiparkinsonism and dystonia were the result of a bullet in midbrain,2 and in another, dystonia was caused by a bullet in internal capsule.3.

20.
Front Hum Neurosci ; 12: 117, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29636671

RESUMO

Hemiparkinsonism duration in patients with Parkinson's disease (PD) is a key time window to study early pathology of PD. We aimed to comprehensively explore the alterations of deformation and structural network in PD patients with hemiparkinsonism, which could potentially disclose the early biomarker for PD. Thirty-one PD patients with hemiparkinsonism and 37 age- and gender- matched normal controls were included in the present study. First of all, we normalized the left hemisphere of structural images as the contralateral side to the affected limbs. Deformation-based morphometry (DBM) was conducted to evaluate the brain atrophy and/or enlargement. structural networks were constructed by thresholding gray matter volume correlation matrices of 116 regions and analyzed using graph theoretical approaches (e.g., small-worldness, global, and nodal measures). Significantly decreased deformation values were observed in the temporoparietal regions like bilateral middle temporal gyri, ipsilateral precuneus and contralateral Rolandic operculum extending to supramarginal and postcentral gyri. Lower deformation values in contralateral middle temporal gyrus were negatively correlated with higher motor impairment which was dominated by akinesia/rigidity. Moreover, nodal reorganization of structural network mainly located in frontal, temporal, subcortex and cerebellum was bilaterally explored in PD patients with hemiparkinsonism. Increased nodal properties could be commonly observed in frontal lobes. Disruption of subcortex including basal ganglia and amygdala was detected by nodal local efficiency and nodal clustering coefficient. Twelve hubs, mainly from paralimbic-limbic and heteromodal networks, were disrupted and, alternatively, 14 hubs, most of which were located in frontal lobes, were additionally detected in PD patients with hemiparkinsonism. In conclusion, during hemiparkinsonism period, mild brain atrophy in the temporoparietal regions and widespread reorganization of structural network, e.g., enhanced frontal function and disruption of basal ganglia nodes, occurred in both hemispheres. With our data, we can also argue that MTG contralateral to the affected limbs (expressing clinically verified brain atrophy) might be a potential living biomarker to monitor disease progression. Therefore, the combination of DBM and structural network analyses can provide a comprehensive and sensitive evaluation for potential pathogenesis of early PD patients with hemiparkinsonism.

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