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1.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33836594

RESUMO

Multiple sclerosis (MS), a putative autoimmune disease of the central nervous system (CNS), commonly presents as relapsing-remitting MS (RRMS), characterized by recurrent episodes of peripheral disabling symptoms resulting from inflammatory CNS damage. Many RRMS patients transition to a chronic disease course with progressive neurological dysfunctions (secondary progressive MS, SPMS), with the progression rate varying between patients and over time. SPMS pathogenesis is now linked to immune-cell-mediated processes, although the mechanisms driving SPMS transition and progression remain elusive, and SPMS lacks biomarkers and effective treatments. We report the crucial involvement of cytotoxic CD4+ T cells expressing Eomes (Eomes+ Th cells) in SPMS pathogenesis-a Th cell subset previously identified in a mouse model of late/chronic autoimmune CNS inflammation. Few Eomes+ Th cells circulate in RRMS patient peripheral blood (n = 44), primary progressive MS (PPMS) patients (n = 25), or healthy controls (n = 42), but Eomes+ Th cells were significantly increased in SPMS (n = 105, P < 0.0001). Strikingly, lymphocytes isolated from SPMS autopsy brain samples revealed CD4+ T cells infiltrating CNS that coexpressed Eomes and the cytotoxic molecule granzyme B. In particular, the Eomes+ Th cell levels were increased in SPMS patients in progressive disease phases versus SPMS patients without current disability increases (P < 0.0001). Moreover, Eomes level acted as a biomarker to predict SPMS patients at risk of disease worsening with over 80% accuracy (ROC-AUC = 0.8276). Overall, our results indicate that granzyme B-expressing Eomes+ T helper cells are involved in the pathogenesis of SPMS, with significant implications for SPMS biomarkers and therapeutic targets.


Assuntos
Esclerose Múltipla Crônica Progressiva/patologia , Proteínas com Domínio T/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto , Idoso , Biomarcadores/sangue , Encéfalo/patologia , Progressão da Doença , Feminino , Granzimas/metabolismo , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/sangue , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/patologia , Adulto Jovem
2.
Artigo em Inglês | MEDLINE | ID: mdl-36913933

RESUMO

INTRODUCTION: Tau protein accumulation in the brain is thought to be one of the causes of progressive supranuclear palsy (PSP). The glymphatic system was discovered a decade ago as a waste drainage system in the brain that promotes the elimination of amyloid-beta and tau protein. We here evaluated the relationships between glymphatic system activity and regional brain volumes in PSP patients. METHOD: Subjects were 24 patients with PSP and 42 healthy participants who underwent diffusion tensor imaging (DTI). We computed the diffusion tensor image analysis along the perivascular space (DTI­ALPS) index as a proxy of glymphatic system activity, and estimated the relationships between the DTI­ALPS index and regional brain volume in PSP patients by whole-brain and region-of-interest analyses, including analyses of the midbrain and third and lateral ventricles. RESULTS: The DTI­ALPS index was significantly lower in patients with PSP, compared with healthy subjects. Further, there were significant correlations between the DTI­ALPS index and the regional brain volumes in the midbrain tegmentum, pons, right frontal lobe, and lateral ventricles in patients with PSP. CONCLUSIONS: Our data suggest that the DTI­ALPS index is a good biomarker for PSP and might be effective to distinguish PSP from other neurocognitive disorders.

3.
Mol Psychiatry ; 26(3): 825-834, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160692

RESUMO

Epilepsy is a diverse brain disorder, and the pathophysiology of its various forms and comorbidities is largely unknown. A recent machine learning method enables us to estimate an individual's "brain-age" from MRI; this brain-age prediction is expected as a novel individual biomarker of neuropsychiatric disorders. The aims of this study were to estimate the brain-age for various categories of epilepsy and to evaluate clinical discrimination by brain-age for (1) the effect of psychosis on temporal lobe epilepsy (TLE), (2) psychogenic nonepileptic seizures (PNESs) from MRI-negative epilepsies, and (3) progressive myoclonic epilepsy (PME) from juvenile myoclonic epilepsy (JME). In total, 1196 T1-weighted MRI scans from healthy controls (HCs) were used to build a brain-age prediction model with support vector regression. Using the model, we calculated the brain-predicted age difference (brain-PAD: predicted age-chronological age) of the HCs and 318 patients with epilepsy. We compared the brain-PAD values based on the research questions. As a result, all categories of patients except for extra-temporal lobe focal epilepsy showed a significant increase in brain-PAD. TLE with hippocampal sclerosis presented a significantly higher brain-PAD than several other categories. The mean brain-PAD in TLE with inter-ictal psychosis was 10.9 years, which was significantly higher than TLE without psychosis (5.3 years). PNES showed a comparable mean brain-PAD (10.6 years) to that of epilepsy patients. PME had a higher brain-PAD than JME (22.0 vs. 9.3 years). In conclusion, neuroimaging-based brain-age prediction can provide novel insight into or clinical usefulness for the diverse symptoms of epilepsy.


Assuntos
Epilepsia do Lobo Temporal , Transtornos Psicóticos , Encéfalo/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico por imagem , Humanos , Neuroimagem , Transtornos Psicóticos/diagnóstico por imagem , Convulsões
4.
Neuroradiology ; 64(4): 825-836, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34693484

RESUMO

PURPOSE: To clarify brain abnormalities on magnetic resonance imaging (MRI) and its clinical implications in lissencephaly/subcortical band heterotopia (LIS/SBH) spectrum patients. METHODS: The clinical severity and classification according to Di Donato were retrospectively reviewed in 23 LIS/SBH spectrum patients. The morphological and signal abnormalities of the brainstem, corpus callosum, and basal ganglia were also assessed. The brainstem distribution pattern of the corticospinal tract (CST) was analyzed by diffusion tensor imaging (DTI) and categorized into two types: normal pattern, in which the CST and medial lemniscus (ML) are separated by the dorsal portion of the transverse pontine fiber, and the abnormal pattern, in which the CST and ML are juxtaposed on the dorsal portion of a single transverse pontine fiber. Correlations between MR grading score and potential additional malformative findings of the brain and clinical symptoms were investigated. RESULTS: All patients with grade 3 (n = 5) showed brainstem deformities, signal abnormalities of pontine surface and had a tendency of basal ganglia deformity and callosal hypoplasia whereas those abnormalities were rarely seen in patients with grade 1 and 2 (n = 18). For DTI analysis, the patients with grade 3 LIS/SBH had typically abnormal CST, whereas the patients with grade 1 and 2 LIS/SBH had normal CST. The classification was well correlated with CST and brainstem abnormalities and clinical severity. CONCLUSION: MR assessment including DTI analysis may be useful in assessing the clinical severity in LIS/BH spectrum and may provide insight into its developmental pathology.


Assuntos
Lissencefalias Clássicas e Heterotopias Subcorticais em Banda , Imagem de Tensor de Difusão , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/diagnóstico por imagem , Lissencefalias Clássicas e Heterotopias Subcorticais em Banda/patologia , Imagem de Tensor de Difusão/métodos , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/patologia , Estudos Retrospectivos
5.
J Sex Med ; 18(2): 231-239, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33243689

RESUMO

BACKGROUND: We previously reported that the combination of the dopamine (DA) receptor agonist apomorphine and the 5-hydroxytryptamine (5-HT2) receptor agonist m-chlorophenylpiperazine (m-CPP) in rats potently and selectively facilitates the ejaculatory response through activation of D2-like and 5-HT2C receptors, respectively. AIM: The aim of this study was to clarify the target level of the proejaculatory effects induced by combination of these agonists. METHODS: For in vivo behavioral studies, apomorphine and m-CPP were given intracerebroventricularly and intrathecally alone or in combination with either drug administered systemically. Male rats were acclimated to observational cages bedded in paper towels, and the occurrence of ex copula ejaculation was assessed by evaluating the presence and weight of ejaculatory plugs dropped from the tip of the penis to the paper towels or adhered to the tip of the penis at 30 min after drug administration. For in vitro contraction studies, seminal vesicles isolated from rats were suspended in an organ bath to test contractile responses to drug combinations, and the effects of the combined drugs on the contractile response of noradrenaline were also tested. MAIN OUTCOME MEASURES: The presence and weight of ejaculatory plugs produced by drug-induced ejaculation and the contractile responses of the seminal vesicle were evaluated. RESULTS: Intrathecal m-CPP (10 µg), but not intracerebroventricular m-CPP, evoked the synergistic effects on ejaculation when used in combination with systemically administered apomorphine (0.1 mg/kg, subcutaneous). Moreover, the synergy between m-CPP and apomorphine was completely abolished by the intrathecal 5-HT2C receptor antagonist SB242084 (10 µg). Intrathecal or intracerebroventricular apomorphine (1-10 µg) evoked proejaculatory effects in combination with systemically administered m-CPP (0.3 mg/kg, intraperitoneal). The selective peripherally acting D2-like receptor agonist carmoxirole did not evoke ejaculation when used in combination with m-CPP. Furthermore, isolated rat seminal vesicles were completely insensitive to the combination of apomorphine and m-CPP. CONCLUSION: These results indicated that the synergistic effects of the drugs on ejaculation were induced at the central level but not at peripheral sites. Our findings also suggested that the 5-HT2C receptor mediated the stimulation of the spinal ejaculatory pattern generator and was synergistically potentiated by the spinal DA receptor and that activation of the supraspinal DA receptor was also involved in mediating these synergistic effects. Yoshizumi M, Yonezawa A, Kimura Y, et al. Central Mechanisms of Apomorphine and m-Chlorophenylpiperazine on Synergistic Action for Ejaculation in Rats. J Sex Med 2021;18:231-239.


Assuntos
Apomorfina , Ejaculação , Animais , Apomorfina/farmacologia , Agonistas de Dopamina/farmacologia , Masculino , Piperazinas/farmacologia , Ratos
6.
J Neuroradiol ; 48(2): 88-93, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32335071

RESUMO

BACKGROUND AND PURPOSE: Beta-propeller protein-associated neurodegeneration (BPAN) is one subtype of neurodegeneration with brain iron accumulation. It is difficult to diagnose BPAN due to the non-specificity of their clinical findings and neuroimaging in early childhood. We experienced four pediatric patients with serial brain MRI and evaluated the alteration of the findings through their course. METHODS: We retrospectively reviewed the clinical findings and 21 MRI findings of the four patients with genetically confirmed pediatric BPAN. We also performed a quantitative MR assessment using the quantitative susceptibility mapping (QSM) values of the globus pallidus (GP), substantia nigra (SN), and deep cerebellar nuclei (DCN) compared to 10 age-matched disease controls. RESULTS: Only one patient was suspected of BPAN based on imaging findings before the genetic diagnosis was made. The other three patients could not be suspected until their Whole-exome sequencings (WES) done. In all four cases, no abnormal signals were noted in the GP and SN at the initial brain MRI, but hypointensities were observed after the ages of 4-7 years on T2-weighted images and after the ages of 2-7 years on susceptibility-weighted images. In three patients, T2 hyperintensity in the bilateral DCN was persistently observed throughout the observational period. Three patients showed transient T2 hyperintensity and swelling in the GP, SN and/or DCN during the episodes of pyrexia and seizures. The other findings included cerebral and cerebellar atrophy, thinning of the corpus callosum, and delayed myelination. The QSM values of the GP and SN were significantly higher in the patients compared to the controls (P=0.005, respectively), but that of the DCN did not differ significantly (P=0.16). CONCLUSION: Brain MRI is a useful method to establish the early diagnosis of BPAN.


Assuntos
Proteínas de Transporte , Doenças Neurodegenerativas , Criança , Pré-Escolar , Humanos , Imageamento por Ressonância Magnética , Doenças Neurodegenerativas/diagnóstico por imagem , Neuroimagem , Estudos Retrospectivos
7.
J Neuroradiol ; 48(6): 419-424, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31889551

RESUMO

BACKGROUND AND PURPOSE: Chorea-acanthocytosis, a rare neurodegenerative disease, affects both the striatum and the medial temporal lobe which may cause involuntary movements and epilepsy, respectively. We examined the imaging changes of the hippocampus/amygdala and the striatum as well as clinical symptoms. MATERIALS AND METHODS: We retrospectively reviewed 29 MRI and 13 SPECT studies and the clinical findings of seven genetically confirmed chorea-acanthocytosis patients. We evaluated the time-dependent imaging changes of the hippocampus/amygdala and striatum and examined the relationships among these images and symptoms. RESULTS: The initial symptom was epilepsy in four patients and involuntary movements in three patients. These symptoms were eventually noted in five and all seven patients, respectively. On MRI, most patients showed striatum atrophy before a hippocampus/amygdala abnormality emerged, but one patient showed a hippocampus/amygdala abnormality before striatum atrophy. Abnormal MRI findings of hippocampus/amygdala were noted in five patients and atrophy of striatum in all seven patients. SPECT demonstrated hypoperfusion of hippocampus/amygdala in three patients and that of striatum in all five available patients. Four patients demonstrated hypoperfusion of striatum earlier than that of hippocampus/amygdala and one patient showed hypoperfusion of both simultaneously. Many imaging abnormal lesions were accompanied by their corresponding symptoms, but not always so. CONCLUSION: Striatum abnormalities were the initial imaging findings in many chorea-acanthocytosis patients, but epilepsy or hippocampus/amygdala imaging abnormalities may be the only findings at the early stage. It is important to understand the detailed clinical and imaging time courses for the diagnosis of chorea-acanthocytosis.


Assuntos
Epilepsia do Lobo Temporal , Neuroacantocitose , Doenças Neurodegenerativas , Atrofia , Hipocampo , Humanos , Imageamento por Ressonância Magnética , Neuroacantocitose/diagnóstico por imagem , Estudos Retrospectivos
8.
J Magn Reson Imaging ; 49(3): 818-824, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30430664

RESUMO

BACKGROUND: Diffusional kurtosis imaging (DKI) and neurite orientation dispersion and density imaging (NODDI) metrics provide more specific information regarding pathological changes than diffusion tensor imaging (DTI). PURPOSE: To detect microstructural abnormalities in myalgic encephalomyelitis (ME) / chronic fatigue syndrome (CFS) patients by using DKI and NODDI metrics. STUDY TYPE: Prospective. POPULATION: Twenty ME/CFS patients and 23 healthy controls were recruited. FIELD STRENGTH/SEQUENCE: Three-b value DWI (b-values = 0, 1000, and 2000 sec/mm2 ) and 3D T1 -weighted images were at 3.0T. ASSESSMENT: Mean kurtosis (MK), neurite density index (NDI), orientation dispersion index (ODI), fractional anisotropy (FA), and mean diffusivity (MD) were calculated. STATISTICAL TESTING: The two-sample t-test analysis in SPM12 software was used to compare the differences between ME/CFS and control groups. RESULTS: In the ME/CFS patients, we observed significant FA decreases in the genu of the corpus callosum and the anterior limb of the right internal capsule (P < 0.05), but no significant difference in MD (P = 0.164); there were also significant MK decreases in the right frontal area, anterior cingulate gyrus, superior longitudinal fasciculus (SLF), and left parietal area (P < 0.05). Significant NDI decreases were observed in the right posterior cingulate gyrus, SLF, and left frontal area of the ME/CFS patients (P < 0.05). Significant ODI decreases were seen in the bilateral occipital areas, right superior temporal gyrus, the anterior limb of internal capsule, and the posterior cingulate gyrus (P < 0.05), and significant ODI increases were revealed in the bilateral occipital and right temporal areas (P < 0.05). DATA CONCLUSION: Right SLF abnormalities may be a diagnostic marker for ME/CFS. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:818-824.


Assuntos
Imagem de Difusão por Ressonância Magnética , Encefalomielite/diagnóstico por imagem , Síndrome de Fadiga Crônica/diagnóstico por imagem , Neuritos/patologia , Adulto , Anisotropia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Neuroradiology ; 60(6): 635-641, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29654334

RESUMO

PURPOSE: Although epilepsy in the elderly has attracted attention recently, there are few systematic studies of neuroimaging in such patients. In this study, we used structural MRI and diffusion tensor imaging (DTI) to investigate the morphological and microstructural features of the brain in late-onset temporal lobe epilepsy (TLE). METHODS: We recruited patients with TLE and an age of onset > 50 years (late-TLE group) and age- and sex-matched healthy volunteers (control group). 3-Tesla MRI scans, including 3D T1-weighted images and 15-direction DTI, showed normal findings on visual assessment in both groups. We used Statistical Parametric Mapping 12 (SPM12) for gray and white matter structural normalization and comparison and used Tract-Based Spatial Statistics (TBSS) for fractional anisotropy and mean diffusivity comparisons of DTI. In both methods, p < 0.05 (family-wise error) was considered statistically significant. RESULTS: In total, 30 patients with late-onset TLE (mean ± SD age, 66.8 ± 8.4; mean ± SD age of onset, 63.0 ± 7.6 years) and 40 healthy controls (mean ± SD age, 66.6 ± 8.5 years) were enrolled. The late-onset TLE group showed significant gray matter volume increases in the bilateral amygdala and anterior hippocampus and significantly reduced mean diffusivity in the left temporofrontal lobe, internal capsule, and brainstem. No significant changes were evident in white matter volume or fractional anisotropy. CONCLUSIONS: Our findings may reflect some characteristics or mechanisms of cryptogenic TLE in the elderly, such as inflammatory processes.


Assuntos
Imagem de Tensor de Difusão/métodos , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/patologia , Idade de Início , Idoso , Anisotropia , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade
10.
Eur J Nucl Med Mol Imaging ; 44(3): 366-372, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27544223

RESUMO

PURPOSE: For the quantitative assessment of dopamine transporter (DAT) using [123I]FP-CIT single-photon emission computed tomography (SPECT) (DaTscan), anatomic standardization is preferable for achieving objective and user-independent quantification of striatal binding using a volume-of-interest (VOI) template. However, low accumulation of DAT in Parkinson's disease (PD) would lead to a deformation error when using a DaTscan-specific template without any structural information. To avoid this deformation error, we applied computed tomography (CT) data obtained using SPECT/CT equipment to anatomic standardization. METHODS: We retrospectively analyzed DaTscan images of 130 patients with parkinsonian syndromes (PS), including 80 PD and 50 non-PD patients. First we segmented gray matter from CT images using statistical parametric mapping 12 (SPM12). These gray-matter images were then anatomically standardized using the diffeomorphic anatomical registration using exponentiated Lie algebra (DARTEL) algorithm. Next, DaTscan images were warped with the same parameters used in the CT anatomic standardization. The target striatal VOIs for decreased DAT in PD were generated from the SPM12 group comparison of 20 DaTscan images from each group. We applied these VOIs to DaTscan images of the remaining patients in both groups and calculated the specific binding ratios (SBRs) using nonspecific counts in a reference area. In terms of the differential diagnosis of PD and non-PD groups using SBR, we compared the present method with two other methods, DaTQUANT and DaTView, which have already been released as software programs for the quantitative assessment of DaTscan images. RESULTS: The SPM12 group comparison showed a significant DAT decrease in PD patients in the bilateral whole striatum. Of the three methods assessed, the present CT-guided method showed the greatest power for discriminating PD and non-PD groups, as it completely separated the two groups. CONCLUSION: CT-guided anatomic standardization using the DARTEL algorithm is promising for the quantitative assessment of DaTscan images.


Assuntos
Doença de Parkinson/diagnóstico por imagem , Compostos Radiofarmacêuticos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/normas , Tropanos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Estudos de Casos e Controles , Corpo Estriado/diagnóstico por imagem , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Padrões de Referência , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos
11.
NMR Biomed ; 29(7): 890-5, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27129076

RESUMO

We examined and compared the temperatures of the intraventricular cerebrospinal fluid (Tv ) and the brain parenchyma (Tp ) using MRI, with reference to the tympanic membrane temperature (Tt ) in healthy subjects. We estimated Tv and Tp values from data gathered simultaneously by MR diffusion-weighted imaging (DWI) and MRS, respectively, in 35 healthy volunteers (17 males, 18 females; age 25-78 years). We also obtained Tt values just before each MR examination to evaluate the relationships among the three temperatures. There were significant positive correlations between Tv and Tp (R = 0.611, p < 0.001). The correlation was also significant after correction for Tt (R = 0.642, p < 0.001). There was no significant correlation between Tv and Tt or between Tp and Tt in the men or the women. Negative correlations were found between Tv and age and between Tp and age in the males but not females. DWI thermometry seems to reflect the intracranial environment as accurately as MRS thermometry. An age-dependent decline in temperature was evident in our male subjects by both DWI and MRS thermometry, probably due to the decrease in cerebral metabolism with age. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Temperatura Corporal/fisiologia , Ventrículos Cerebrais/fisiologia , Líquido Cefalorraquidiano/fisiologia , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Espectroscopia de Ressonância Magnética/métodos , Termografia/métodos , Adulto , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores Sexuais , Temperatura
12.
Epilepsy Behav ; 62: 239-45, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27497065

RESUMO

Graph theory is an emerging method to investigate brain networks. Altered cerebral blood flow (CBF) has frequently been reported in temporal lobe epilepsy (TLE), but graph theoretical findings of CBF are poorly understood. Here, we explored graph theoretical networks of CBF in TLE using arterial spin labeling imaging. We recruited patients with TLE and unilateral hippocampal sclerosis (HS) (19 patients with left TLE, and 21 with right TLE) and 20 gender- and age-matched healthy control subjects. We obtained all participants' CBF maps using pseudo-continuous arterial spin labeling and analyzed them using the Graph Analysis Toolbox (GAT) software program. As a result, compared to the controls, the patients with left TLE showed a significantly low clustering coefficient (p=0.024), local efficiency (p=0.001), global efficiency (p=0.010), and high transitivity (p=0.015), whereas the patients with right TLE showed significantly high assortativity (p=0.046) and transitivity (p=0.011). The group with right TLE also had high characteristic path length values (p=0.085), low global efficiency (p=0.078), and low resilience to targeted attack (p=0.101) at a trend level. Lower normalized clustering coefficient (p=0.081) in the left TLE and higher normalized characteristic path length (p=0.089) in the right TLE were found also at a trend level. Both the patients with left and right TLE showed significantly decreased clustering in similar areas, i.e., the cingulate gyri, precuneus, and occipital lobe. Our findings revealed differing left-right network metrics in which an inefficient CBF network in left TLE and vulnerability to irritation in right TLE are suggested. The left-right common finding of regional decreased clustering might reflect impaired default-mode networks in TLE.


Assuntos
Circulação Cerebrovascular/fisiologia , Epilepsia do Lobo Temporal/fisiopatologia , Hipocampo/patologia , Lobo Temporal/patologia , Adulto , Mapeamento Encefálico/métodos , Epilepsia do Lobo Temporal/patologia , Feminino , Hipocampo/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose/patologia , Esclerose/fisiopatologia , Software , Lobo Temporal/fisiopatologia
13.
Cureus ; 16(1): e53072, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38410305

RESUMO

BACKGROUND: To clarify the neural correlates underlying psychogenic non-epileptic seizures (PNES), we compared glymphatic system activity between patients with PNES and healthy participants using diffusion tensor imaging (DTI)-analysis along the perivascular space (ALPS) method. METHODS: The DTI scans were acquired from 16 patients with PNES and 25 healthy participants. We computed the DTI-ALPS index as an index of glymphatic system function and estimated the disease-related changes in the DTI-ALPS index and brain structures in PNES patients. RESULTS: There were no significant differences in the DTI-ALPS index between patients with PNES and healthy participants. On the other hand, patients with PNES had decreased fractional anisotropy values in the bilateral posterior cingula, a higher mean diffusivity value around the left insula, and a lower gray matter volume in the bilateral amygdalae compared with healthy participants. CONCLUSIONS: Patients with PNES exhibited an impairment of white matter integrity and a reduction of gray matter volume, but no glymphatic-system changes. These findings will play a significant role in our comprehension of this complex illness.

14.
Magn Reson Med Sci ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38382996

RESUMO

PURPOSE: Neuromelanin is visualized by optimizing the conditions of longitudinal relaxation (T1)-weighted imaging (T1WI). Although it was originally developed in 2D imaging, 3D imaging has been also reported, and T1WI sequences with magnetization transfer (MT) pulses are now widely used in 3D gradient echo (GRE) sequences. In this study, we assert that the use of spectral presaturation with inversion recovery (SPIR) may also be useful as an alternative to MT pulses, and we optimize SPIR and compare it with MT. METHODS: Neuromelanin images with MT pulse and SPIR (flip angles [FAs] = 19º, 22º, and 25º) were acquired from 30 healthy volunteers. To achieve the same acquisition time of 5 min, the slab thickness of the MT images was less than 1/3 of those of the SPIR images; the acquisition areas for MT and SPIR were the brainstem and the whole brain, respectively. Visual and quantitative evaluation was performed and compared on the four sequences acquired for the substantia nigra pars compacta (SNc) and the locus coeruleus (LC). For visual assessment, we used the mean score from a 3-point scale by two evaluators. For quantitative evaluation, the contrast ratios of SNc and LC were calculated in comparison with the background tissue signal. RESULTS: In visual assessments, the mean scores of the SPIR FA19º and FA22º images were better than others in the SNc. Regarding LC, the SPIR FA22º image yielded the best mean score. In quantitative evaluations, the MT image was significantly lower than the other three images in SNc. Regarding LC, there were no significant differences among the four acquired images (MT and SPIR FA19º, FA22º, and FA25º). CONCLUSIONS: Detection of neuromelanin in SNc and LC was improved by the use of SPIR compared to MT pulse in 3D neuromelanin imaging.

15.
Neurol Neuroimmunol Neuroinflamm ; 11(2): e200206, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38350043

RESUMO

BACKGROUND AND OBJECTIVES: Neuromyelitis optica (NMO) is an autoimmune astrocytopathy mediated by anti-AQP4 antibody-producing B cells. Recently, a B-cell subset highly expressing CD11c and T-bet, originally identified as age-associated B cells, has been shown to be involved in the pathogenesis of various autoimmune diseases. The objective of this study was to determine the relationship between the frequency of CD11chigh B cells per CD19+ B cells in the peripheral blood of patients with NMO and the clinical profiles including the brain volume. METHODS: In this observational study, 45 patients with anti-AQP4 antibody-positive NMO in remission and 30 healthy control subjects (HCs) were enrolled. Freshly isolated peripheral blood mononuclear cells were analyzed for immune cell phenotypes. The frequency of CD11chigh B cells per CD19+ B cells was assessed by flow cytometry and was evaluated in association with the clinical profiles of patients. Brain MRI data from 26 patients were included in the study for the analysis on the correlation between CD11chigh B-cell frequency and brain atrophy. RESULTS: We found that the frequency of CD11chigh B cells in CD19+ B cells was significantly increased in patients with NMO compared with HCs. The expansion of CD11chigh B cells significantly correlated with EDSS, past relapse numbers, and disease duration. In addition, a higher frequency of CD11chigh B cells negatively correlated with total brain, white matter, and gray matter volumes and positively correlated with T2/FLAIR high lesion volumes. When the past clinical relapse episodes of patients with or without the expansion of CD11chigh B cells were compared, relapses in the brain occurred more frequently in patients with CD11chigh B-cell expansion. CD11chigh B cells had distinct features including expression of chemokine receptors associated with migration into peripheral inflammatory tissues and antigen presentation. CD11chigh B-cell frequency was positively correlated with T peripheral helper-1 (Tph-1) cell frequency. DISCUSSION: Even during the relapse-free period, CD11chigh B cells could expand in the long disease context, possibly through the interaction with Tph-1 cells. The increased frequency of CD11chigh B cells associated with brain atrophy and disease severity, indicating that this cell population could be involved in chronic neuroinflammation in NMO.


Assuntos
Doenças do Sistema Nervoso Central , Neuromielite Óptica , Substância Branca , Humanos , Aquaporina 4 , Leucócitos Mononucleares/metabolismo , Substância Branca/patologia , Doenças do Sistema Nervoso Central/complicações , Recidiva
16.
J Neurol Sci ; 462: 123090, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38865876

RESUMO

BACKGROUND AND PURPOSE: Neuromyelitis optica spectrum disorder is a demyelinating and inflammatory affliction that often leads to visual disturbance. Various imaging techniques, including free-water imaging, have been used to determine neuroinflammation and degeneration. Therefore, this study aimed at determining multimodal imaging differences between patients with neuromyelitis optica spectrum disorder, especially those with visual disturbance, and healthy controls. MATERIALS AND METHODS: Eighty-five neuromyelitis optica spectrum disorder patients and 89 age- and sex-matched healthy controls underwent 3-T magnetic resonance imaging (MRI). We analyzed adjusted brain-predicted age difference, voxel-based morphometry, and free-water-corrected diffusion tensor imaging (DTI) by tract-based spatial statistics in each patient group (MRI-positive/negative neuromyelitis optica spectrum disorder patients with or without a history of visual disturbance) compared with the healthy control group. RESULTS: MRI-positive neuromyelitis optica spectrum disorder patients exhibited reduced volumes of the bilateral thalamus. Tract-based spatial statistics showed diffuse white matter abnormalities in all DTI metrics in MRI-positive neuromyelitis optica spectrum disorder patients with a history of visual disturbance. In MRI-negative neuromyelitis optica spectrum disorder patients with a history of visual disturbance, voxel-based morphometry showed volume reduction of bilateral thalami and optic radiations, and tract-based spatial statistics revealed significantly lower free-water-corrected fractional anisotropy and higher mean diffusivity in the posterior dominant distributions, including the optic nerve radiation. CONCLUSION: Free-water-corrected DTI and voxel-based morphometry analyses may reflect symptoms of visual disturbance in neuromyelitis optica spectrum disorder.


Assuntos
Imagem de Tensor de Difusão , Imageamento por Ressonância Magnética , Imagem Multimodal , Neuromielite Óptica , Transtornos da Visão , Humanos , Neuromielite Óptica/diagnóstico por imagem , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Imagem de Tensor de Difusão/métodos , Transtornos da Visão/diagnóstico por imagem , Transtornos da Visão/etiologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Adulto Jovem , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
17.
Epilepsy Behav Rep ; 26: 100674, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38764719

RESUMO

Mild malformation of cortical development with oligodendroglial hyperplasia (MOGHE) is a recently proposed epileptogenic entity that is difficult to detect on MRI. We present a case of MOGHE that was successfully detected on T1WI-chemical shift-selective saturation (CHESS) MRI. The clinical presentation, MRI including T1WI-CHESS, functional images, and pathology findings of a 14-year-old Japanese girl diagnosed with MOGHE are described. T1WI-CHESS revealed an abnormal high signal along the affected lesion, whereas the findings shown by the other MR sequences were less obvious; interictal fluorodeoxyglucose-positron emission tomography indicated slightly decreased accumulation in the lesion, and subtraction ictal single photon emission computed tomography co-registered to MRI showed an increased blood flow. Together these observations suggest that T1WI-CHESS may be a useful MR sequence for detecting the lesions in patients with MOGHE.

18.
J Alzheimers Dis ; 99(4): 1441-1453, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38759008

RESUMO

Background: Cortical neurodegenerative processes may precede the emergence of disease symptoms in patients with Alzheimer's disease (AD) by many years. No study has evaluated the free water of patients with AD using gray matter-based spatial statistics. Objective: The aim of this study was to explore cortical microstructural changes within the gray matter in AD by using free water imaging with gray matter-based spatial statistics. Methods: Seventy-one participants underwent multi-shell diffusion magnetic resonance imaging, 11C-Pittsburgh compound B positron emission tomography, and neuropsychological evaluations. The patients were divided into two groups: healthy controls (n = 40) and the AD spectrum group (n = 31). Differences between the groups were analyzed using voxel-based morphometry, diffusion tensor imaging, and free water imaging with gray matter-based spatial statistics. Results: Voxel-based morphometry analysis revealed gray matter volume loss in the hippocampus of patients with AD spectrum compared to that in controls. Furthermore, patients with AD spectrum exhibited significantly greater free water, mean diffusivity, and radial diffusivity in the limbic areas, precuneus, frontal lobe, temporal lobe, right putamen, and cerebellum than did the healthy controls. Overall, the effect sizes of free water were greater than those of mean diffusivity and radial diffusivity, and the larger effect sizes of free water were thought to be strongly correlated with AD pathology. Conclusions: This study demonstrates the utility of applying voxel-based morphometry, gray matter-based spatial statistics, free water imaging and diffusion tensor imaging to assess AD pathology and detect changes in gray matter.


Assuntos
Doença de Alzheimer , Substância Cinzenta , Tomografia por Emissão de Pósitrons , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Masculino , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Idoso , Imagem de Tensor de Difusão , Compostos de Anilina , Tiazóis , Testes Neuropsicológicos , Água , Imagem de Difusão por Ressonância Magnética , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Idoso de 80 Anos ou mais , Processamento de Imagem Assistida por Computador
19.
J Neuroradiol ; 40(2): 121-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23428241

RESUMO

OBJECTIVES: The uncinate fasciculus (UF), a major white-matter tract connecting the frontal and temporal lobes, is related to cognitive/behavioral function. Recently, the UF has been suggested to constitute an indirect pathway of the "semantic ventral pathway" in association with the inferior longitudinal fasciculus (ILF). This retrospective study aimed to evaluate damage to the UF and ILF in patients with progressive supranuclear palsy (PSP) using diffusion tensor tract-specific analysis. MATERIAL AND METHODS: Diffusion tensor imaging (DTI) of 16 PSP patients with Richardson's syndrome (PSP-RS) and 21 age-matched volunteers were obtained. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values for the bilateral UF and ILF were calculated by tract-specific analysis. Student's t test was used to evaluate the differences between the patients and controls. Also, voxel-based morphometry (VBM) was performed using 3D T1-weighted images to explore the regional atrophy of gray matter in the patients. RESULTS: In patients with PSP-RS, FA of the left UF was significantly decreased compared with the controls, while significant increases in ADC were found in the UF and ILF bilaterally. VBM analysis showed significant clusters of reduced gray matter in the frontal cortex (predominantly in the lateral orbitofrontal cortex, pars opercularis and mesial frontal cortex) and subcortical nuclei (midbrain, caudate and thalamic). CONCLUSION: This study has shown that patients with PSP-RS had impairment of the UF and ILF. Damage to the UF is thought to be related to atrophy of the orbitofrontal cortex and may possibly be correlated with the cognitive/behavioral impairment seen in PSP.


Assuntos
Algoritmos , Imagem de Tensor de Difusão/métodos , Lobo Frontal/patologia , Interpretação de Imagem Assistida por Computador/métodos , Fibras Nervosas Mielinizadas/patologia , Paralisia Supranuclear Progressiva/patologia , Lobo Temporal/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Vias Neurais/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Int J Dev Neurosci ; 83(7): 665-673, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37604479

RESUMO

BACKGROUND AND PURPOSE: Alternating hemiplegia of childhood (AHC) is a rare neurodevelopmental disease caused by ATP1A3 mutations. Using voxel-based morphometry (VBM) analysis, we compared an AHC patient cohort with controls. Additionally, with single-case VBM analysis, we assessed the associations between clinical severity and brain volume in patients with AHC. MATERIALS AND METHODS: To investigate structural brain changes in gray matter (GM) and white matter (WM) volumes between 9 patients with AHC and 20 age-matched controls, VBM analysis was performed using three-dimensional T1-weighted magnetic resonance imaging. Single-case VBM analysis was also performed on nine patients with AHC to investigate the associations between the respective volumes of GM/WM differences and the motor level, cognitive level, and status epilepticus severity in patients with AHC. RESULTS: Compared with controls, patients with AHC showed significant GM volume reductions in both hippocampi and diffuse cerebellum, and there were WM reductions in both cerebral hemispheres. In patients with AHC, cases with more motor dysfunction, the less GM/WM volume of cerebellum was shown. Three of the six cases with cognitive dysfunction showed a clear GM volume reduction in the insulae. Five of the six cases with status epilepticus showed the GM volume reduction in hippocampi. One case had severe status epilepticus without motor dysfunction and showed no cerebellar atrophy. CONCLUSION: With single-case VBM analysis, we could show the association between region-specific changes in brain volume and the severity of various clinical symptoms even in a small sample of subjects.


Assuntos
Imageamento por Ressonância Magnética , Estado Epiléptico , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/patologia , Substância Cinzenta/patologia , Estado Epiléptico/patologia , ATPase Trocadora de Sódio-Potássio
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