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1.
Brain ; 146(1): 266-277, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35136957

RESUMO

Two clinical phenotypes characterize the onset of amyotrophic lateral sclerosis (ALS): the spinal variant, with symptoms beginning in the limbs, and the bulbar variant, affecting firstly speech and swallowing. The two variants show some distinct features in the histopathology, localization and prognosis, but to which extent they really differ clinically and pathologically remains to be clarified. Recent neuropathological and neuroimaging studies have suggested a broader spreading of the neurodegenerative process in ALS, extending beyond the motor areas, toward other cortical and deep grey matter regions, many of which are involved in visual processing and saccadic control. Indeed, a wide range of eye movement deficits have been reported in ALS, but they have never been used to distinguish the two ALS variants. Since quantifying eye movements is a very sensitive and specific method for the study of brain networks, we compared different saccadic and visual search behaviours across spinal ALS patients (n = 12), bulbar ALS patients (n = 6) and healthy control subjects (n = 13), along with cognitive and MRI measures, with the aim to define more accurately the two patients subgroups and possibly clarify a different underlying neural impairment. We found separate profiles of visually-guided saccades between spinal (short saccades) and bulbar (slow saccades) ALS, which could result from the pathologic involvement of different pathways. We suggest an early involvement of the parieto-collicular-cerebellar network in spinal ALS and the fronto-brainstem circuit in bulbar ALS. Overall, our data confirm the diagnostic value of the eye movements analysis in ALS and add new insight on the involved neural networks.


Assuntos
Esclerose Lateral Amiotrófica , Córtex Motor , Humanos , Esclerose Lateral Amiotrófica/patologia , Movimentos Sacádicos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Tronco Encefálico
2.
J Dairy Res ; 90(2): 191-199, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37326234

RESUMO

We evaluated the possibility of increasing the storage temperature of raw milk for Provolone Valpadana cheesemaking, to identify the most suitable conditions of time and temperature for a pre-maturation process. We used Principal Component Analysis (PCA) to analyze the overall effects of different storage conditions on chemical, nutritional and technological characteristics of the raw milk. Four different thermal storage cycles, two at fixed temperature/time (6 and 12°C for 60 h) and two with two-phase thermal cycle (10 and 12°C for 15 h, followed by refrigeration at 4°C for 45 h) were studied. Although a moderate heterogeneity among raw milks from the 11 producers of Provolone Valpadana cheese was observed, PCA revealed the critical aspects of the extreme storage conditions (60 h of refrigeration). Some samples resulted in anomalous behaviors, probably related to unexpected fermentation phenomena occurring with increasing storage temperature. The acidification and the increase in the contents of lactic acid, soluble calcium, and degree of retinol isomerization observed in the anomalous samples can compromise the technological functionality of milk. Conversely, the storage with a two-phase thermal cycle did not lead to variations in any measured characteristic, suggesting that mild refrigeration conditions (10 or 12°C for 15 h followed by 4°C for 45 h) could be a good compromise in favoring milk pre-maturation without altering its quality characteristics.


Assuntos
Leite , Refrigeração , Animais , Temperatura , Leite/química , Refrigeração/veterinária
3.
Neural Plast ; 2022: 6197505, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35880231

RESUMO

Over the past few years, the possibility of modulating fast brain oscillatory activity in the gamma (γ) band through transcranial alternating current stimulation (tACS) has been discussed in the context of both cognitive enhancement and therapeutic scenarios. However, the effects of tACS targeting regions outside the motor cortex, as well as its spatial specificity, are still unclear. Here, we present a concurrent tACS-fMRI block design study to characterize the impact of 40 Hz tACS applied over the left and right dorsolateral prefrontal cortex (DLPFC) in healthy subjects. Results suggest an increase in blood oxygenation level-dependent (BOLD) activity in the targeted bilateral DLPFCs, as well as in surrounding brain areas affected by stimulation according to biophysical modeling, i.e., the premotor cortex and anterior cingulate cortex (ACC). However, off-target effects were also observed, primarily involving the visual cortices, with further effects on the supplementary motor areas (SMA), left subgenual cingulate, and right superior temporal gyrus. The specificity of 40 Hz tACS over bilateral DLPFC and the possibility for network-level effects should be considered in future studies, especially in the context of recently promoted gamma-induction therapeutic protocols for neurodegenerative disorders.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Mapeamento Encefálico/métodos , Córtex Pré-Frontal Dorsolateral , Humanos , Imageamento por Ressonância Magnética/métodos , Projetos Piloto , Córtex Pré-Frontal/diagnóstico por imagem , Estimulação Transcraniana por Corrente Contínua/métodos
4.
Molecules ; 26(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443426

RESUMO

Proteomics and metabolomics are analytic tools used in combination with bioinformatics to study proteins and metabolites which contribute to describing complex biological systems. The growing interest in research concerning the resolution of these systems has stimulated the development of sophisticated procedures and new applications. This paper introduces the evolution of statistical techniques for the treatment of data, suggesting the possibility to successfully characterize the milk-whey syneresis process by applying two-dimensional correlation analysis (2DCOR) to a series of CE electropherograms referring to milk-whey samples collected during cheese manufacturing. Two cheese-making processes to produce hard cheese (Grana type) and fresh cheese (Crescenza) were taken as models. The applied chemometric tools were shown to be useful for the treatment of data acquired in a systematically perturbed chemical system as a function of time.


Assuntos
Ácidos/análise , Queijo/análise , Leite/química , Nitrogênio/análise , Soro do Leite/química , Animais , Eletroforese Capilar , Projetos Piloto
5.
J Neurosci Res ; 98(10): 1843-1856, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32686203

RESUMO

Dynamics within and between functional resting-state networks have a crucial role in determining both healthy and pathological brain functioning in humans. The possibility to noninvasively interact and selectively modulate the activity of networks would open to relevant applications in neuroscience. Here we tested a novel approach for multichannel, network-targeted transcranial direct current stimulation (net-tDCS), optimized to increase excitability of the sensorimotor network (SMN) while inducing cathodal inhibitory modulation over prefrontal and parietal brain regions negatively correlated with the SMN. Using an MRI-compatible multichannel transcranial electrical stimulation (tES) device, 20 healthy participants underwent real and sham tDCS while at rest in the MRI scanner. Changes in functional connectivity (FC) during and after stimulation were evaluated, looking at the intrinsic FC of the SMN and the strength of the negative connectivity between SMN and the rest of the brain. Standard, bifocal tDCS targeting left motor cortex (electrode ~C3) and right frontopolar (~Fp2) regions was tested as a control condition in a separate sample of healthy subjects to investigate network specificity of multichannel stimulation effects. Net-tDCS induced greater FC increase over the SMN compared to bifocal tDCS, during and after stimulation. Moreover, exploratory analysis of the impact of net-tDCS on negatively correlated networks showed an increase in the negative connectivity between SMN and prefrontal/parietal areas targeted by cathodal stimulation both during and after real net-tDCS. Results suggest preliminary evidence of the possibility of manipulating distributed network connectivity patterns through net-tDCS, with potential relevance for the development of cognitive enhancement and therapeutic tES solutions.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
6.
Food Microbiol ; 69: 116-122, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28941892

RESUMO

The ability of folate-producer strains of Streptococcus thermophilus to accumulate folates and the expression of two target genes (folK and folP), involved in the folate biosynthesis, were studied during milk fermentation. An over-expression of folK took place only in the early phase of growth, whereas folP was mainly expressed in the mid log-phase of growth and declined thereafter. The accumulation of total folates, which was quantified by a microbiological assay, was strain-dependent. Two major forms of folates, i.e. tetrahydrofolate (THF) and 5-methyl-tetrahydrofolate (5-Met-THF), were identified and quantified by HPLC. With respect to the level accumulated by a weak folate producer (St 383), used as calibrator in the expression experiments and as control in folate quantification in milk, the strains St 563 and St 399 produced 5-Met-THF in amounts significantly higher than THF. The possibility of using selected folate-producer S. thermophilus strains as functional cultures for a bio-fortification of dairy products is discussed.


Assuntos
Meios de Cultura/metabolismo , Ácido Fólico/biossíntese , Streptococcus thermophilus/crescimento & desenvolvimento , Streptococcus thermophilus/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bovinos , Cromatografia Líquida de Alta Pressão , Fermentação , Streptococcus thermophilus/isolamento & purificação
7.
J Stroke Cerebrovasc Dis ; 27(12): 3575-3577, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30228010

RESUMO

Diagnosis and treatment of acute ischemic stroke is challenging during pregnancy. We present a diagnostic strategy in a pregnant woman with suspect of acute stroke. We perform magnetic resonance with arterial spin labeling sequence, an X-ray and contrast medium safe perfusion technique. Arterial spin labeling can detects collateral vessels in patient with acute ischemic stroke. Demonstrating collateral vessels is relevant for better understanding prognosis and for improving the diagnostic assessment in pregnancy.


Assuntos
Encéfalo/diagnóstico por imagem , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Aborto Induzido , Adulto , Encéfalo/cirurgia , Procedimentos Endovasculares , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Gravidez , Acidente Vascular Cerebral/cirurgia
8.
J Physiol ; 595(11): 3607-3620, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28168705

RESUMO

KEY POINTS: A cerebellar dentate nuclei (DN) contribution to volitional oculomotor control has recently been hypothesized but not fully understood. Cerebrotendinous xanthomatosis (CTX) is a rare neurometabolic disease typically characterized by DN damage. In this study, we compared the ocular movement characteristics of two sets of CTX patients, with and without brain MRI evidence of DN involvement, with a set of healthy subjects. Our results suggest that DN participate in voluntary behaviour, such as the execution of antisaccades, and moreover are involved in controlling the precision of the ocular movement. The saccadic abnormalities related to DN involvement were independent of global and regional brain atrophy. Our study confirms the relevant role of DN in voluntary aspects of oculomotion and delineates specific saccadic abnormalities that could be used to detect the involvement of DN in other cerebellar disorders. ABSTRACT: It is well known that the medial cerebellum controls saccadic speed and accuracy. In contrast, the role of the lateral cerebellum (cerebellar hemispheres and dentate nuclei, DN) is less well understood. Cerebrotendinous xanthomatosis (CTX) is a lipid storage disorder due to mutations in CYP27A1, typically characterized by DN damage. CTX thus provides a unique opportunity to study DN in human oculomotor control. We analysed horizontal and vertical visually guided saccades and horizontal antisaccades of 19 CTX patients. Results were related to the presence/absence of DN involvement and compared with those of healthy subjects. To evaluate the contribution of other areas, abnormal saccadic parameters were compared with global and regional brain volumes. CTX patients executed normally accurate saccades with normal main sequence relationships, indicating that the brainstem and medial cerebellar structures were functionally spared. Patients with CTX executed more frequent multistep saccades and directional errors during the antisaccade task than controls. CTX patients with DN damage showed less precise saccades with longer latencies, and more frequent directional errors, usually not followed by corrections, than either controls or patients without DN involvement. These saccadic abnormalities related to DN involvement but were independent of global and regional brain atrophy. We hypothesize that two different cerebellar networks contribute to the metrics of a movement: the medial cerebellar structures determine accuracy, whereas the lateral cerebellar structures control precision. The lateral cerebellum (hemispheres and DN) also participates in modulating goal directed gaze behaviour, by prioritizing volitional over reflexive movements.


Assuntos
Núcleos Cerebelares/fisiologia , Movimentos Sacádicos , Xantomatose Cerebrotendinosa/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Núcleos Cerebelares/diagnóstico por imagem , Núcleos Cerebelares/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
J Stroke Cerebrovasc Dis ; 26(7): e129-e132, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28479185

RESUMO

BACKGROUND: Takayasu arteritis (TA), also known as aortoarteritis and pulseless disease, is an autoimmune, idiopathic, large-vessel vasculitis that primarily affects the aorta and its major branches, the coronary arteries, and the pulmonary arteries. METHODS: This is a peculiar clinical and radiological pattern of TA in a young female Caucasian. Her medical history included diagnosis of ulcerative rectocolitis at the age of 14. Because of the occurrence of anemia and exacerbation of rectocolitis, she had started infliximab associated with low doses of cortisone and mesalazine. Three months before admission, therapy with infliximab was discontinued because of the onset of fever, sore throat, and the increase in the neck pain. Imaging is crucial to achieve a proper diagnosis and the main differential diagnosis of this setting is arterial dissection. Magnetic resonance angiography (MRA) and color Doppler sonography (CDS) have been able to demonstrate rare but possible arteriovenous fistula in TA patients. This is the first report on arteriovenous fistula of cervical venous plexus in TA patients. CONCLUSION: (1) TA has to be suspected in young woman with neck pain, even without neurological symptoms. (2) Magnetic resonance imaging and CDS can depict wall thickening and abnormal caliber in the involved vessels. (3) MRA and CDS are able to demonstrate rare but possible arteriovenous fistula in TA patients. (4) Rectocolitis therapy could be a trigger factor of wall vessel involvement.


Assuntos
Fístula Arteriovenosa/diagnóstico por imagem , Colite Ulcerativa/complicações , Angiografia por Ressonância Magnética , Pescoço/irrigação sanguínea , Arterite de Takayasu/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Adulto , Anti-Inflamatórios/uso terapêutico , Fístula Arteriovenosa/etiologia , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Angiografia por Tomografia Computadorizada , Diagnóstico Diferencial , Feminino , Fármacos Gastrointestinais/uso terapêutico , Humanos , Imagem Multimodal , Cervicalgia/diagnóstico por imagem , Cervicalgia/etiologia , Valor Preditivo dos Testes , Arterite de Takayasu/complicações
10.
Neuroradiology ; 58(7): 705-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27130616

RESUMO

INTRODUCTION: Differentiation between normal solid (non-cystic) pineal glands and pineal pathologies on brain MRI is difficult. The aim of this study was to assess the size of the solid pineal gland in children (0-5 years) and compare the findings with published pineoblastoma cases. METHODS: We retrospectively analyzed the size (width, height, planimetric area) of solid pineal glands in 184 non-retinoblastoma patients (73 female, 111 male) aged 0-5 years on MRI. The effect of age and gender on gland size was evaluated. Linear regression analysis was performed to analyze the relation between size and age. Ninety-nine percent prediction intervals around the mean were added to construct a normal size range per age, with the upper bound of the predictive interval as the parameter of interest as a cutoff for normalcy. RESULTS: There was no significant interaction of gender and age for all the three pineal gland parameters (width, height, and area). Linear regression analysis gave 99 % upper prediction bounds of 7.9, 4.8, and 25.4 mm(2), respectively, for width, height, and area. The slopes (size increase per month) of each parameter were 0.046, 0.023, and 0.202, respectively. Ninety-three percent (95 % CI 66-100 %) of asymptomatic solid pineoblastomas were larger in size than the 99 % upper bound. CONCLUSION: This study establishes norms for solid pineal gland size in non-retinoblastoma children aged 0-5 years. Knowledge of the size of the normal pineal gland is helpful for detection of pineal gland abnormalities, particularly pineoblastoma.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Glândula Pineal/diagnóstico por imagem , Pinealoma/diagnóstico por imagem , Pré-Escolar , Diagnóstico Diferencial , Europa (Continente) , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Glândula Pineal/patologia , Pinealoma/patologia , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
11.
Am J Hum Genet ; 90(3): 467-77, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22341971

RESUMO

Manganese is essential for several metabolic pathways but becomes toxic in excessive amounts. Manganese levels in the body are therefore tightly regulated, but the responsible protein(s) remain incompletely known. We studied two consanguineous families with neurologic disorders including juvenile-onset dystonia, adult-onset parkinsonism, severe hypermanganesemia, polycythemia, and chronic hepatic disease, including steatosis and cirrhosis. We localized the genetic defect by homozygosity mapping and then identified two different homozygous frameshift SLC30A10 mutations, segregating with disease. SLC30A10 is highly expressed in the liver and brain, including in the basal ganglia. Its encoded protein belongs to a large family of membrane transporters, mediating the efflux of divalent cations from the cytosol. We show the localization of SLC30A10 in normal human liver and nervous system, and its depletion in liver from one affected individual. Our in silico analyses suggest that SLC30A10 possesses substrate specificity different from its closest (zinc-transporting) homologs. We also show that the expression of SLC30A10 and the levels of the encoded protein are markedly induced by manganese in vitro. The phenotype associated with SLC30A10 mutations is broad, including neurologic, hepatic, and hematologic disturbances. Intrafamilial phenotypic variability is also present. Chelation therapy can normalize the manganesemia, leading to marked clinical improvements. In conclusion, we show that SLC30A10 mutations cause a treatable recessive disease with pleomorphic phenotype, and provide compelling evidence that SLC30A10 plays a pivotal role in manganese transport. This work has broad implications for understanding of the manganese biology and pathophysiology in multiple human organs.


Assuntos
Proteínas de Transporte de Cátions/genética , Intoxicação por Manganês/genética , Proteínas de Membrana Transportadoras/genética , Doenças Metabólicas/genética , Transtornos Parkinsonianos/genética , Idoso , Sequência de Aminoácidos , Encéfalo/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Mapeamento Cromossômico/métodos , Feminino , Mutação da Fase de Leitura/genética , Genes Recessivos , Predisposição Genética para Doença , Células Hep G2 , Homozigoto , Humanos , Imuno-Histoquímica/métodos , Fígado/metabolismo , Masculino , Manganês/metabolismo , Intoxicação por Manganês/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Doenças Metabólicas/metabolismo , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fenótipo , Alinhamento de Sequência/métodos , Células Tumorais Cultivadas , Transportador 8 de Zinco
13.
Neurol Genet ; 9(6): e200104, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38239817

RESUMO

Objectives: The objective of this case report was to describe the first report of FOLR1 variants associated with adult-onset paucisymptomatic leukoencephalopathy associated with cerebral folate deficiency (CFD). Methods: Considering the patient's symptoms, a nonprogressive leukoencephalopathy was suspected. CSF 5-methyltetrahydrofolate levels were low (10 nmol/L, normal range 41-117). With no other identifiable causes, a genetic analysis was conducted, revealing a compound heterozygous FOLR1 variation (c.45G>T and c. 493+2T>C). Results: A 47-year-old man with a history of drug and alcohol abuse was admitted to the hospital for double vision and postural instability. MRI of the brain was performed, which showed bilateral leukoencephalopathy. Diffusion tensor imaging revealed a diffuse reduction in fractional anisotropy, suggesting microstructural changes. MRI of the brain and overall clinical picture were stable on subsequent serial examinations. Discussion: Scientific evidence supports the deleterious effect of c.45G>T and c.493+2T>C variations on the folate receptor-α (FRα) protein structure and function. The weakness of the expression and function of FRα without elimination of its function caused by specific compound heterozygous variations may explain the atypical features observed in our patient. Although rare, CFD should be considered in paucisymptomatic adult patients with stable diffuse MRI white matter changes.

15.
Front Neuroimaging ; 1: 1034241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37555181

RESUMO

Diffusion tensor imaging (DTI) is considered feasible for the nerve plexuses' imaging and quantitative evaluation but its value in the clinical practice is still virtually unexplored. We present the DTI profile of a case of acute varicella-zoster virus (VZV)-related brachial plexopathy. A 72-year-old woman presented with left upper-limb segmental paresis involving the spinal metamers C6-C7, preceded by a painful dermatomal vesicular eruption in C5-T1 dermatomes. Clinical and electrophysiological findings and magnetic resonance imaging indicated a plexus involvement. DTI analysis showed decreased fractional anisotropy (FA) and an increase of all the other diffusivity indexes, i.e., mean, axial, and radial diffusivity. The mechanisms underlying DTI parameter differences between healthy and pathologic brachial plexus sides could be related to microstructural fiber damage. Water diffusion is affected within the nerve roots by increasing the diffusion distance, leading to increased diffusion perpendicular to the largest eigenvalue and therefore to decreased FA values The role of DTI in clinical practice has not been defined yet. Additional quantitative and qualitative DTI information could improve the assessment and follow-up of brachial plexopathy.

16.
Am J Med Genet A ; 155A(10): 2446-52, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21910234

RESUMO

Creatine deficiency syndrome due to mutations in X-linked SLC6A8 gene results in nonspecific intellectual disability (ID). Diagnosis cannot be established on clinical grounds and is often based on the assessment of brain creatine levels by magnetic resonance spectroscopy (MRS). Considering high costs of MRS and necessity of sedation, this technique cannot be used as a first level-screening test. Likewise, gene test analysis is time consuming and not easily accessible to all laboratories. In this article feasibility of urine analysis (creatine/creatinine (Cr/Crn) ratio) performed by nuclear magnetic resonance (NMR) as a first level-screening test is explored. Before running a systematic selection of cases a preliminary study for further molecular analysis is shown. NMR urine spectra (n = 1,347) of male patients with an ID without a clinically recognizable syndrome were measured. On the basis of abnormal Cr/Crn ratio, three patients with the highest values were selected for molecular analysis. A confirmatory second urine test was positive in two patients and diagnosis was further confirmed by a decreased brain creatine level and by SLC6A8 gene analysis. A de novo mutation was identified in one. Another patient inherited a novel mutation from the mother who also has a mild ID. A repeat urine test was negative in the third patient and accordingly creatine level in the brain and SLC6A8 gene analysis both gave a normal result. We conclude that Cr/Crn ratio measured by NMR for male patients represents a rapid and useful first level screening test preceding molecular analysis.


Assuntos
Encefalopatias Metabólicas Congênitas/diagnóstico , Creatina/urina , Espectroscopia de Ressonância Magnética , Deficiência Intelectual Ligada ao Cromossomo X/diagnóstico , Proteínas do Tecido Nervoso/genética , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/genética , Encéfalo/metabolismo , Encefalopatias Metabólicas Congênitas/urina , Creatina/deficiência , Creatina/metabolismo , Humanos , Masculino , Deficiência Intelectual Ligada ao Cromossomo X/urina , Mutação/genética , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/deficiência , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/urina , Reação em Cadeia da Polimerase
17.
Neurol Sci ; 31(5): 653-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20544248

RESUMO

The supranuclear paresis of the abducens system, also known as posterior internuclear ophthalmoplegia of abduction, is a very rare disorder clinically characterized by unilateral or bilateral abduction paresis sometimes associated with nystagmus of the contralateral adducting eye, slowing of abduction saccades, and intact horizontal vestibulo-ocular reflex. Here, we report a 35-year-old woman who presented transient left side abduction deficit in conjunction, as the only symptom of self-limited viral encephalitis of the brainstem. Brain MRI including DWI and ADC maps showed an area of abnormal signal intensity in the mid-right ponto-mesencephalic junction. PCR analysis of cerebrospinal fluid showed an enterovirus infection. Spontaneous clinical recovery rapidly occurred 2 days after onset. The brainstem lesion was undetectable at 5-week brain MRI follow-up.


Assuntos
Tronco Encefálico/virologia , Encefalite Viral/complicações , Encefalite Viral/patologia , Paralisia Supranuclear Progressiva/etiologia , Adulto , Tronco Encefálico/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos
18.
Biomol Concepts ; 11(1): 137-141, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32589590

RESUMO

Endothelins are powerful vasoconstrictor peptides that play numerous other roles. Endothelin-1 (ET1) is the principal isoform produced by the endothelium in the human cardiovascular system. Endothelin-3 (ET3) and its rPptor affinity have been demonstrated to support neuronal repair mechanisms throughout life. In multiple sclerosis (MS), the role of vasoactive peptides are not well defined. Here we focus on ET3, specifically the plasma levels between MS patients and healthy subjects. Furthermore, we evaluated the changes in ET1 and ET3 plasma levels during different disease phases, the correlation between ET3 and cerebral circulation time, and the relationship between ET1 and ET3. In MS patients, the ET3 plasma levels were altered in a time-dependent manner. These results could support a putative role of ET3 in neuroprotection and/or neuroimmune modulation over time.


Assuntos
Endotelina-1/sangue , Endotelina-3/sangue , Esclerose Múltipla Recidivante-Remitente/metabolismo , Barreira Hematoencefálica/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Fatores de Tempo
19.
J Alzheimers Dis ; 74(4): 1057-1068, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32144979

RESUMO

Recent studies have revealed the possible role of choroid plexus (ChP) in Alzheimer's disease (AD). T1-weighted MRI is the modality of choice for the segmentation of ChP in humans. Manual segmentation is considered the gold-standard technique, but given its time-consuming nature, large-scale neuroimaging studies of ChP would be impossible. In this study, we introduce a lightweight segmentation algorithm based on the Gaussian Mixture Model (GMM). We compared its performance against manual segmentation as well as automated segmentation by Freesurfer in three separate datasets: 1) patients with structural MRIs enhanced with contrast (n = 19), 2) young healthy subjects (n = 20), and 3) patients with AD (n = 20). GMM outperformed Freesurfer and showed high similarity with manual segmentation. To further assess the algorithm's performance in large scale studies, we performed GMM segmentations in young healthy subjects from the Human Connectome Project (n = 1,067), as well as healthy controls, mild cognitive impairment (MCI), and AD patients from the Alzheimer's Disease Neuroimaging Initiative (n = 509). In both datasets, GMM segmented ChP more accurately than Freesurfer. To show the clinical importance of accurate ChP segmentation, total AV1451 (tau) PET binding to ChP was measured in 108 MCI and 32 AD patients. GMM was able to reveal the higher AV1451 binding to ChP in AD compared with MCI. Our results provide evidence for the utility of the GMM in accurately segmenting ChP and show its clinical relevance in AD. Future structural and functional studies of ChP will benefit from GMM's accurate segmentation.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Plexo Corióideo/diagnóstico por imagem , Proteínas tau/metabolismo , Adulto , Idoso , Doença de Alzheimer/patologia , Encéfalo/patologia , Estudos de Casos e Controles , Plexo Corióideo/anatomia & histologia , Plexo Corióideo/patologia , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Tomografia por Emissão de Pósitrons
20.
Cardiovasc Intervent Radiol ; 43(1): 94-102, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31410533

RESUMO

PURPOSE: To retrospectively assess safety and potential effectiveness of percutaneous intervertebral disc coagulation therapy (PDCT) using plasma thermal reaction for the treatment of lumbar and cervical disc hernias resistant to medical therapy. MATERIALS AND METHODS: Forty-four patients (age range 18-87 years, mean 52.7) with contained and extruded symptomatic lumbar (N = 48) and cervical (N = 6) disc hernias in the absence of free fragments causing radiculopathy without improvement after 6-week conservative therapy were enrolled. Pretreatment discography has been performed in every patient. Spine MRI was performed before the procedure and 4 months later, in order to check post-PDCT changes. Technical success was defined as correct placement of PDCT fiber; clinical outcomes were evaluated using visual analog scale (VAS) and the Oswestry Disability Index (ODI) before the procedure and after 4 months. RESULTS: A total of 54 levels have been treated with 98% technical success; in 12 patients (27%), the treatment was performed in two levels at the same time. All patients well tolerated the procedure; most patients (N = 39; 89%) had significant improvement in symptoms, with ODI score reduction from 47.61 ± 8.7 to 13.38 ± 9.4 (p < 0.001). The mean pre-PDCT VAS score was 7.47 ± 0.8. VAS score was decreased down to 1.36 ± 1.6 at final follow-up (p < 0.001). There were no cases of infection, nerve damage, or bleeding. CONCLUSIONS: PDCT can be an effective and safe for minimally invasive indirect decompression for cervical and lumbar hernia resistant to conservative treatment, particularly when patients are correctly selected.


Assuntos
Discotomia Percutânea/métodos , Deslocamento do Disco Intervertebral/cirurgia , Fotocoagulação a Laser/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Europa (Continente) , Feminino , Humanos , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dados Preliminares , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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