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1.
Hum Mutat ; 41(4): 807-824, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31898848

RESUMEN

Minisatellites, also called variable number of tandem repeats (VNTRs), are a class of repetitive elements that may affect gene expression at multiple levels and have been correlated to disease. Their identification and role as expression quantitative trait loci (eQTL) have been limited by their absence in comparative genomic hybridization and single nucleotide polymorphisms arrays. By taking advantage of cap analysis of gene expression (CAGE), we describe a new example of a minisatellite hosting a transcription start site (TSS) which expression is dependent on the repeat number. It is located in the third intron of the gene nitrogen permease regulator like protein 3 (NPRL3). NPRL3 is a component of the GAP activity toward rags 1 protein complex that inhibits mammalian target of rapamycin complex 1 (mTORC1) activity and it is found mutated in familial focal cortical dysplasia and familial focal epilepsy. CAGE tags represent an alternative TSS identifying TAGNPRL3 messenger RNAs (mRNAs). TAGNPRL3 is expressed in red blood cells both at mRNA and protein levels, it interacts with its protein partner NPRL2 and its overexpression inhibits cell proliferation. This study provides an example of a minisatellite that is both a TSS and an eQTL as well as identifies a new VNTR that may modify mTORC1 activity.


Asunto(s)
Proteínas Activadoras de GTPasa/metabolismo , Regulación de la Expresión Génica , Repeticiones de Minisatélite , Sitio de Iniciación de la Transcripción , Línea Celular , Proteínas Activadoras de GTPasa/genética , Genómica/métodos , Genotipo , Humanos , Intrones , Familia de Multigenes , Polimorfismo Genético , Caperuzas de ARN , Interferencia de ARN , ARN Interferente Pequeño
2.
J Stroke Cerebrovasc Dis ; 25(9): 2196-202, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27425766

RESUMEN

OBJECTIVE: Stroke is one of the leading causes of disability and death in the world. The endocannabinoid (eCB) system is upregulated in several neurological diseases including stroke. A previous animal study demonstrated an increased expression of the endocannabinoid receptor 1 (CB1R) in the penumbra area surrounding the ischemic core, suggesting a crucial role in inflammation/reperfusion after stroke. Regarding the localization of CB1/CB2 receptors, animal studies showed that cortical neurons, activated microglia, and astroglia are involved. Our aim was to evaluate the cerebral expression of CB1R in the ischemic brain areas of 9 patients who died due to acute cerebral infarction in the middle cerebral artery territory. METHODS: The cerebral autoptic tissue was collected within 48 hours since death. Ischemic and contralateral normal-appearing areas were identified. After tissue preprocessing, 4-µm-thick cerebral sections were incubated with the primary CB1R antibodies (Cayman Chemical Company, Ann Arbor, MI). Thereafter, all cerebral sections were hematoxylin treated. In each section, the total cell number and CB1R-positive cells were counted and the CB1R-positive cell count ratio was calculated. For statistical analysis, Student's t-test was used. RESULTS: In normal tissue, CB1R-positive neurons were the majority; a few non-neuronal cells expressed CB1R. In the ischemic areas, a few neurons were detectable. A significant increase in total CB1R staining was found in the ischemic regions compared to contralateral areas. CONCLUSIONS: We found an increase in CB1R expression in the ischemic region (neuronal and non-neuronal cell staining), suggesting the inflammatory reaction to the ischemic insult. Whether such response might mediate neuroprotective actions or excitotoxicity-related detrimental effects is still unclear.


Asunto(s)
Autopsia , Corteza Cerebral/metabolismo , Receptor Cannabinoide CB1/metabolismo , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patología , Regulación hacia Arriba/genética , Anciano , Anciano de 80 o más Años , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Femenino , Humanos , Masculino , Cambios Post Mortem , Estudios Retrospectivos , Estadística como Asunto , Accidente Cerebrovascular/diagnóstico por imagen , Tomografía Computarizada por Rayos X
3.
BMC Genomics ; 16: 876, 2015 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-26510930

RESUMEN

BACKGROUND: Parkinson's disease (PD) is a chronic progressive neurodegenerative disorder that is clinically defined in terms of motor symptoms. These are preceded by prodromal non-motor manifestations that prove the systemic nature of the disease. Identifying genes and pathways altered in living patients provide new information on the diagnosis and pathogenesis of sporadic PD. METHODS: Changes in gene expression in the blood of 40 sporadic PD patients and 20 healthy controls ("Discovery set") were analyzed by taking advantage of the Affymetrix platform. Patients were at the onset of motor symptoms and before initiating any pharmacological treatment. Data analysis was performed by applying Ranking-Principal Component Analysis, PUMA and Significance Analysis of Microarrays. Functional annotations were assigned using GO, DAVID, GSEA to unveil significant enriched biological processes in the differentially expressed genes. The expressions of selected genes were validated using RT-qPCR and samples from an independent cohort of 12 patients and controls ("Validation set"). RESULTS: Gene expression profiling of blood samples discriminates PD patients from healthy controls and identifies differentially expressed genes in blood. The majority of these are also present in dopaminergic neurons of the Substantia Nigra, the key site of neurodegeneration. Together with neuronal apoptosis, lymphocyte activation and mitochondrial dysfunction, already found in previous analysis of PD blood and post-mortem brains, we unveiled transcriptome changes enriched in biological terms related to epigenetic modifications including chromatin remodeling and methylation. Candidate transcripts as CBX5, TCF3, MAN1C1 and DOCK10 were validated by RT-qPCR. CONCLUSIONS: Our data support the use of blood transcriptomics to study neurodegenerative diseases. It identifies changes in crucial components of chromatin remodeling and methylation machineries as early events in sporadic PD suggesting epigenetics as target for therapeutic intervention.


Asunto(s)
Enfermedad de Parkinson/genética , Transcriptoma/genética , Anciano , Homólogo de la Proteína Chromobox 5 , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
Br J Psychiatry ; 206(2): 145-52, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25431431

RESUMEN

BACKGROUND: Dementia with Lewy bodies (DLB) is underrecognised in clinical settings. AIMS: To investigate whether performing a (123)I-ioflupane injection ((123)I-FP-CIT also called DaTSCAN™) single photon emission computed tomography (SPECT) scan in patients with possible DLB would lead to a more certain diagnosis (probable DLB or non-DLB dementia). METHOD: We randomised 187 patients with possible DLB 2:1 to have a scan or not (control group). The outcome measure was a change in diagnosis to probable DLB or non-DLB. RESULTS: There were 56 controls and 114 scanned patients, of whom 43% had an abnormal scan. More patients in the imaging group had a change in diagnosis compared with controls at 8 and 24 weeks (61% (n = 70) v. 4% (n = 2) and 71% (n = 77) v. 16% (n = 9); both P<0.0001). Clinicians were more likely to change the diagnosis if the scan was abnormal (82%) than if it was normal (46%). CONCLUSIONS: Imaging significantly contributed to a more certain diagnosis, proving to be a useful adjunct in the work-up of patients with possible DLB.


Asunto(s)
Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Enfermedad por Cuerpos de Lewy/diagnóstico por imagen , Nortropanos , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Encéfalo/metabolismo , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas
5.
Neuroepidemiology ; 41(1): 54-61, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23711404

RESUMEN

BACKGROUND: We conducted a retrospective population-based study to estimate the incidence of amyotrophic lateral sclerosis (ALS) in Friuli Venezia Giulia, Italy, from 2001 to 2009. METHODS: Multiple sources were used for case ascertainment: Health databases, archives of the neurology departments and of the regional chapter of the Italian ALS Association. The diagnosis was validated through clinical documentation review. Crude and standardized incidence rates (IRs) per 100,000 person-years were calculated. RESULTS: We identified 262 incident ALS cases, 50.4% men, 4.2% familial. Half of the patients had spinal onset (56.8% in men) and 25.2% bulbar (29% in women). Bulbar onset had a similar frequency in women (31.7%) and men (31.5%) aged 67 or above at diagnosis. The crude IR was 2.72 (95% confidence interval, 95% CI, 2.39-3.05) and the male:female ratio 1.08. The IR peaked in the 65-74 age group, with a second increase in men 85 years and older. The IR standardized to the 2001 Italian population was 2.38 (95% CI 2.13-2.63) and to the 2000 European population 2.58 (95% CI 2.34-2.81). CONCLUSIONS: This retrospective study found IRs of ALS in the range of Italian and European prospective population-based registries, suggesting an almost complete case ascertainment.


Asunto(s)
Esclerosis Amiotrófica Lateral/epidemiología , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Sistema de Registros , Estudios Retrospectivos , Distribución por Sexo
6.
Brain Topogr ; 22(4): 307-17, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19499197

RESUMEN

Parietal cortex subserves various cognitive tasks, ranging from attention to visuo-motor skills. It is part of a parieto-frontal network involved in attention, and part of the visual dorsal stream, opposed to the visual ventral stream, although increasing evidence suggests interchange of information between them. In this study, co-registration of Transcranial Magnetic Stimulation (TMS) and Electroencephalographic activity (EEG) has been used to investigate the spreading of cortical connections from the parietal cortex in healthy volunteers. TMS on the left parietal cortex activated a network of prefrontal regions in the contra-lateral hemisphere in a time range of 102-167 ms after the stimulus. Moreover, activation in the ipsi-lateral middle temporal and fusiform gyri was observed at 171-177 ms after delivery of TMS. Findings suggest the existence of late driven connections between parietal and prefrontal regions that could partially represent the neural pathway related to attention, even if, in this experiment, no attentional processing was requested. Late connections between dorsal and ventral streams were also evident, confirming previous evidence about interchange of information between them. Conclusively, the present investigation confirms that a great amount of information spreads from parietal cortex to different regions in the brain, supporting the idea that connections are more complex and articulated than those proposed. Present findings also suggest that the simultaneous recording of EEG during the application of TMS is a promising tool for the study of connections in the brain.


Asunto(s)
Encéfalo/fisiología , Vías Visuales/fisiología , Adulto , Mapeo Encefálico/métodos , Electroencefalografía/métodos , Potenciales Evocados , Femenino , Humanos , Masculino , Procesamiento de Señales Asistido por Computador , Factores de Tiempo , Estimulación Magnética Transcraneal/métodos , Adulto Joven
7.
Lipids Health Dis ; 9: 47, 2010 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-20470384

RESUMEN

BACKGROUND: Endocannabinoids (eCBs) are ubiquitous lipid mediators that act on specific (CB1, CB2) and non-specific (TRPV1, PPAR) receptors. Despite many experimental animal studies proved eCB involvement in the pathogenesis of stroke, such evidence is still lacking in human patients. Our aim was to determine eCB peripheral levels in acute stroke patients and evaluate their relationship with clinical disability and stroke volume. METHODS: A cohort of ten patients with a first acute (within six hours since symptoms onset) ischemic stroke and a group of eight age- and sex-matched normal subjects were included. Groups were also matched for metabolic profile. All subjects underwent a blood sample collection for anandamide (AEA), 2-arachidonoylglycerol (2-AG) and palmitoylethanolamide (PEA) measurement; blood sampling was repeated in patients on admission (T0), at 6 (T1) and 18 hours (T2) thereafter. Patients neurological impairment was assessed using NIHSS and Fugl-Meyer Scale arm subitem (FMSa); stroke volume was determined on 48 h follow-up brain CT scans. Blood samples were analyzed by liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry. RESULTS: 1)T0 AEA levels were significantly higher in stroke patients compared to controls. 2)A significant inverse correlation between T0 AEA levels and FMSa score was found. Moreover a positive correlation between T0 AEA levels and stroke volume were found in stroke patients. T0 PEA levels in stroke patients were not significantly different from the control group, but showed a significant correlation with the NIHSS scores. T0 2-AG levels were lower in stroke patients compared to controls, but such difference did not reach the significance threshold. CONCLUSIONS: This is the first demonstration of elevated peripheral AEA levels in acute stroke patients. In agreement with previous murine studies, we found a significant relationship between AEA or PEA levels and neurological involvement, such that the greater the neurological impairment, the higher were these levels.


Asunto(s)
Ácidos Araquidónicos/sangre , Ácidos Palmíticos/sangre , Alcamidas Poliinsaturadas/sangre , Accidente Cerebrovascular/etiología , Anciano , Anciano de 80 o más Años , Amidas , Moduladores de Receptores de Cannabinoides/sangre , Cromatografía Liquida , Endocannabinoides , Etanolaminas , Glicéridos/sangre , Humanos , Masculino , Espectrometría de Masas , Metabolómica , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/diagnóstico
8.
Sci Rep ; 9(1): 6151, 2019 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-30992490

RESUMEN

Early diagnosis of Parkinson's disease (PD) remains a challenge to date. New evidence highlights the potential clinical value of circulating trace amines (TAs) in early-stage PD and their involvement in disease progression. A new ultra performance chromatography mass spectrometry (UPLC-MS/MS) method was developed to quantify plasmatic TAs, and the catecholamines and indolamines pertaining to the same biochemical pathways. Three groups of subjects were recruited: 21 de novo, drug untreated, PD patients, 27 in treatment PD patients and 10 healthy subjects as controls. Multivariate and univariate data analyses were applied to reveal metabolic changes among the groups in attempt to discover new putative markers for early PD detection and disease progression. Different circulating levels of tyrosine (p = 0.002), tyramine (p < 0.001), synephrine (p = 0.015), norepinephrine (p = 0.012), metanephrine (p = 0.001), ß-phenylethylamine (p = 0.001) and serotonin (p = 0.006) were found among the three groups. While tyramine behaves as a putative biomarker for early-stage PD (AUC = 0.90) tyramine, norepinephrine, and tyrosine appear to act as biomarkers of disease progression (AUC > 0.75). The findings of this pilot cross-sectional study suggest that biochemical anomalies of the aminergic and indolic neurotransmitters occur in PD patients. Compounds within the TAs family may constitute putative markers for early stage detection and progression of PD.


Asunto(s)
Aminas Biogénicas/sangre , Enfermedad de Parkinson/sangre , Adulto , Anciano , Biomarcadores/sangre , Estudios Transversales , Progresión de la Enfermedad , Diagnóstico Precoz , Femenino , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Enfermedad de Parkinson/diagnóstico , Serotonina/sangre , Sinefrina/sangre , Tiramina/sangre , Tirosina/sangre
9.
Am J Alzheimers Dis Other Demen ; 23(2): 167-76, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18184948

RESUMEN

Vascular dementia (VaD) is associated with a large amount of heterogeneity, as it groups together a broad category of patients in whom various manifestations of cognitive decline are attributed to cerebrovascular or cardiovascular disease. Thus, a study was designed to determine the effects of rivastigmine on cognitive function, global daily living performance, and behavioral disorders in VaD patients versus an active control (nimodipine), stratifying patients according to the type of VaD, subcortical vascular dementia (sVAD), and multi-infarct dementia (MID). The trial was a prospective study. This study shows that long-term treatment with rivastigmine, at dosages approved for therapeutic use in Alzheimer's disease, produces significant improvement in all behavioral symptoms in 2 forms of VaD, MID and sVaD, except delusions. It also suggests that rivastigmine may enable a reduction in concomitant neuroleptics and benzodiazepines in VaD, especially in MID. The results are discussed with an overview of the literature.


Asunto(s)
Demencia por Múltiples Infartos/tratamiento farmacológico , Demencia Vascular/tratamiento farmacológico , Fenilcarbamatos/uso terapéutico , Actividades Cotidianas/psicología , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Benzodiazepinas/efectos adversos , Benzodiazepinas/uso terapéutico , Cognición/efectos de los fármacos , Trastornos del Conocimiento/tratamiento farmacológico , Trastornos del Conocimiento/psicología , Deluciones/tratamiento farmacológico , Deluciones/psicología , Demencia por Múltiples Infartos/psicología , Demencia Vascular/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Contracción Muscular/efectos de los fármacos , Náusea/inducido químicamente , Fármacos Neuroprotectores/efectos adversos , Fármacos Neuroprotectores/uso terapéutico , Pruebas Neuropsicológicas , Nimodipina/efectos adversos , Nimodipina/uso terapéutico , Fenilcarbamatos/efectos adversos , Estudios Prospectivos , Rivastigmina , Resultado del Tratamiento , Vasodilatadores/efectos adversos , Vasodilatadores/uso terapéutico
10.
Vasc Health Risk Manag ; 4(2): 395-402, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18561514

RESUMEN

Physiologically, the cerebral autoregulation system allows maintenance of constant cerebral blood flow over a wide range of blood pressure. In old people, there is a progressive reshape of cerebral autoregulation from a sigmoid curve to a straight line. This implies that any abrupt change in blood pressure will result in a rapid and significant change in cerebral blood flow. Hypertension has often been observed to be a risk factor for vascular dementia (VaD) and sometimes for Alzheimer disease although not always. Indeed, high blood pressure may accelerate cerebral white matter lesions, but white matter lesions have been found to be facilitated by excessive fall in blood pressure, including orthostatic dysregulation and postprandial hypotension. Many recent studies observed among other data, that there was a correlation between systolic pressure reduction and cognitive decline in women, which was not accounted for by other factors. Baseline blood pressure level was not significantly related to cognitive decline with initial good cognition. Some researchers speculate that blood pressure reduction might be an early change of the dementing process. The most confounding factor is that low pressure by itself might be a predictor of death; nevertheless, the effect of low blood pressure on cognition is underestimated because of a survival bias. Another explanation is that clinically unrecognized vascular lesions in the brain or atherosclerosis are responsible for both cognitive decline and blood pressure reduction. We discuss the entire process, and try to define a possible mechanism that is able to explain the dynamic by which hypotension might be related to dementia.


Asunto(s)
Enfermedad de Alzheimer/etiología , Circulación Cerebrovascular , Cognición , Demencia Vascular/etiología , Hipotensión/complicaciones , Factores de Edad , Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/psicología , Animales , Presión Sanguínea , Demencia Vascular/fisiopatología , Demencia Vascular/psicología , Femenino , Homeostasis , Humanos , Hipotensión/fisiopatología , Hipotensión/psicología , Masculino , Factores de Riesgo , Vasodilatación
11.
Pharmacol Ther ; 109(1-2): 274-83, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16202453

RESUMEN

Arterial hypertension is one of the main risk factors for cerebrovascular diseases, and antihypertensive treatment has significantly reduced their associated mortality. However, morbidity has not been reduced to a similar extent and a still increasing number of patients suffers from recurring strokes and from the disabling consequences of cerebrovascular diseases and develops progressive cognitive impairment. It is still debated to what extent antihypertensive treatment may prevent the development of cognitive dysfunction, due to the lack of a focused approach to vascular cognitive impairment, to the lack of a systematic study of the early phases of dementia, and to the use of diagnostic tests that are not sensitive and specific for a slow onset clinical condition, such as dementia. The aim of the present expert consensus report is to enlist the diagnostic tools that are currently available to assess mild cognitive impairment (MCI) and early dementia and that are sensitive and specific enough to be used in observational, longitudinal, and interventional clinical research studies, aiming to investigate the impact of antihypertensive drugs on vascular dementia (VD).


Asunto(s)
Antihipertensivos/uso terapéutico , Trastornos del Conocimiento/diagnóstico , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Animales , Biomarcadores , Trastornos del Conocimiento/diagnóstico por imagen , Humanos , Hipertensión/diagnóstico por imagen , Imagen por Resonancia Magnética , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Ultrasonografía
12.
Funct Neurol ; 21(3): 137-40, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17049131

RESUMEN

Peripheral neuropathy is the most common symptom in patients with hepatitis C virus (HCV) associated mixed cryoglobulinaemia, in whom it may be the first clinical manifestation. Very frequently, the medical therapy proposed to treat HCV and cryoglobulinaemia causes an exacerbation of the disabling neuropathy. Therefore, other neuropathy treatments have been proposed, such as alternative immunosuppressive agents (steroids or cyclosporine) and plasma exchange, which, according to case reports, have yielded inconsistent results and presumably exert only temporary effects as they do not promote clearance of HCV. We present five cases of cryoglobulinaemia-related neuropathy resistant to steroids and gabapentin. Oxcarbazepine was introduced and produced moderate and persistent relief of symptoms without side effects.


Asunto(s)
Analgésicos no Narcóticos/uso terapéutico , Carbamazepina/análogos & derivados , Crioglobulinemia/complicaciones , Hepatitis C/complicaciones , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Anticonvulsivantes/uso terapéutico , Carbamazepina/uso terapéutico , Enfermedad Crónica , Crioglobulinemia/tratamiento farmacológico , Crioglobulinemia/virología , Resistencia a Medicamentos , Femenino , Hepatitis C/tratamiento farmacológico , Humanos , Masculino , Oxcarbazepina , Enfermedades del Sistema Nervioso Periférico/etiología , Resultado del Tratamiento
15.
J Neurol Sci ; 229-230: 215-8, 2005 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15760642

RESUMEN

Increasing evidence supports a pathogenic role of heparan sulphate (HS) in the development of dementia. Since HS proteoglycans are present in the endothelial cells and perivascular basement membrane, we wanted to assess blood titres of HS antibodies (Abs) in patients with vascular dementia (VD) and in patients with Alzheimer's disease (AD) with cerebrovascular disease (CVD) [mixed dementia (MixD)]. Moreover, plasma levels of homocysteine, an independent risk factor for the development of dementia as well as for CVD, were also determined. High HS Abs titres were present in one patient with VD and in two patients with mixed dementia, as well as in two neurological control patients (stroke and epilepsy). Increased homocysteine levels were found in 62.5% of patients with mixed dementia, in 22.2% of the VD subjects, in 54.2% of patients with CVD, and in 41.2% of patients with other neurological diseases. The present findings suggest that neither elevated HS Abs titres nor increased homocysteinemia may represent a useful biochemical marker for the diagnosis of VD.


Asunto(s)
Anticuerpos , Demencia Vascular/diagnóstico , Heparitina Sulfato/inmunología , Homocisteína/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Demencia Vascular/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Ácido Fólico/sangre , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Vitamina B 12/sangre
16.
Recenti Prog Med ; 96(12): 599-603, 2005 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-16496744

RESUMEN

Using f-MRI, we have studied the changes induced by the performance of a complex sequential motor task in the cortical areas of nine akinetic PD patients and compared to that of healthy volunteers. Compared with normal subjects, PD patients showed a reduction of activation of motor and SMA areas, an increase of activation of parietal areas and a bilateral activation of cerebellar hemispheres, which are likely to participate in the attempt to recruit parallel motor circuits in order to overcome the striatocortical defective loop.


Asunto(s)
Cerebelo/fisiopatología , Imagen por Resonancia Magnética , Enfermedad de Parkinson/fisiopatología , Desempeño Psicomotor , Adulto , Anciano , Antiparkinsonianos/uso terapéutico , Estudios de Casos y Controles , Corteza Cerebral/fisiopatología , Cuerpo Estriado/fisiopatología , Femenino , Humanos , Levodopa/uso terapéutico , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/tratamiento farmacológico
17.
Brain Res ; 951(2): 330-5, 2002 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-12270513

RESUMEN

The time-course and relation to dose of regional metabolic rates for glucose (rCMRglc) were measured in awake adult Fischer-344 rats after administration of acetyl-L-carnitine (ALCAR), an agent that modulates neuronal energy processes and neurotransmitter synthesis. rCMRglc were determined with the quantitative [(14)C]2-deoxy-D-glucose technique in 50 brain regions at 10, 30 and 60 min after i.v. administration of ALCAR 500 mg/kg and at 30 min after ALCAR 250 and 700 mg/kg or coadministration of acetate (500 mg/kg) and carnitine (500 mg/kg). ALCAR resulted in significant rCMRglc increases that were maximal by 30 min; by that time, ALCAR 250 produced small, non-significant increase in rCMRglc (no region affected, mean increase 13%) and ALCAR 500 and 750 similar, larger increases in rCMRglc (eight and 11 brain regions affected, mean increases 21 and 22%, respectively). In contrast with ALCAR, carnitine plus acetate did not alter significantly rCMRglc in any brain regions, suggesting that acetate metabolism and carrier are not involved in ALCAR pharmacological activities. ALCAR increased rCMRglc more markedly in subcortical cholinergic (i.e. diagonal band, preoptic magnocellular area) and non-cholinergic (i.e. locus coeruleus, median raphe) nuclei and, to a lesser degree, in limbic and sensorimotor cortical areas. The topographic distribution of rCMRglc increases induced by ALCAR differs from those produced by cholinergic muscarinic agonists and suggest a preferential activation of nicotinic receptors.


Asunto(s)
Acetilcarnitina/farmacología , Química Encefálica/efectos de los fármacos , Glucosa/metabolismo , Nootrópicos/farmacología , Animales , Carnitina/farmacología , Circulación Cerebrovascular/fisiología , Hemodinámica/fisiología , Cinética , Masculino , Ratas , Ratas Endogámicas F344
18.
J Neuroimaging ; 24(3): 273-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23279290

RESUMEN

BACKGROUND: Recent studies suggest that alterations in the cerebrospinal venous system may play a role in multiple sclerosis (MS) and that chronic cerebrospinal venous insufficiency correlates with clinical features of MS patients. OBJECTIVES: To evaluate the vascularization of optic nerve (ONr) and measure ONe thickness by color Doppler ultrasonography in MS patients with and without previous optic neuritis (ONe). SUBJECTS AND METHODS: We assessed flow variables in the ophthalmic artery, central retinal artery, and central retinal vein and measured the diameter of ONe in 46 relapsing-remitting MS patients and 37 healthy controls (HC). Twenty-two MS patients had previous ONe and 24 MS patients had not. Patients with acute ONe were not included. We examined and compared 63 unaffected and 29 affected eyes of MS patients with 74 control eyes. RESULTS: Regarding flow variables, we did not find any significant difference between HC, MS affected, and unaffected eyes. Comparing ONr diameters, we found a progressive significant thinning of the ONr from HC to MS patients without and with past ONe. CONCLUSIONS: We found no significant alteration in the arterial-venous vascularization of both affected and unaffected ONr compared with HC. We demonstrated the possibility to detect ONr atrophy in MS patients.


Asunto(s)
Esclerosis Múltiple/diagnóstico por imagen , Arteria Oftálmica/diagnóstico por imagen , Nervio Óptico/irrigación sanguínea , Nervio Óptico/diagnóstico por imagen , Neuritis Óptica/diagnóstico por imagen , Arteria Retiniana/diagnóstico por imagen , Vena Retiniana/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Esclerosis Múltiple/complicaciones , Neuritis Óptica/etiología , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Ultrasonografía
19.
Cortex ; 49(3): 781-92, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22225881

RESUMEN

INTRODUCTION: Developmental stuttering (DS) is viewed as a motor speech-specific disorder, although several lines of research suggest that DS is a symptom of a broader motor disorder. We investigated corticospinal excitability in adult DS and normal speakers. METHODS: Transcranial magnetic stimulation (TMS) was administered over left/right hand representation of the motor cortex while recording motor evoked potentials (MEPs) from the contralateral first dorsal interosseous (FDI) muscle. Resting, active motor thresholds, silent period threshold and duration were measured. A stimulus-response curve at resting was also obtained to evaluate MEP amplitudes. RESULTS: Lower corticospinal responses in the left hemisphere of DS were found, as indicated by a reduction of peak-to-peak MEP amplitudes compared to normal speakers. CONCLUSIONS: This provides further evidence that DS may be a general motor deficit that also involves motor non-speech-related structures. Moreover, our results confirm that DS may be related to left hemisphere hypoactivation and/or lower left hemisphere dominance. The present data and protocol may be useful for diagnosis of subtypes of DS that may benefit from pharmacological treatment by targeting the general level of cortical excitability.


Asunto(s)
Potenciales Evocados Motores/fisiología , Lateralidad Funcional/fisiología , Corteza Motora/fisiopatología , Tractos Piramidales/fisiopatología , Tartamudeo/fisiopatología , Adulto , Estimulación Eléctrica , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiología , Estimulación Magnética Transcraneal
20.
Front Hum Neurosci ; 7: 803, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24324426

RESUMEN

The premotor cortex is one of the fundamental structures composing the neural networks of the human brain. It is implicated in many behaviors and cognitive tasks, ranging from movement to attention and eye-related activity. Therefore, neural circuits that are related to premotor cortex have been studied to clarify their connectivity and/or role in different tasks. In the present work, we aimed to investigate the propagation of the neural activity evoked in the dorsal premotor cortex using transcranial magnetic stimulation/electroencephalography (TMS/EEG). Toward this end, interest was focused on the neural dynamics elicited in long-ranging temporal and spatial networks. Twelve healthy volunteers underwent a single-pulse TMS protocol in a resting condition with eyes closed, and the evoked activity, measured by EEG, was compared to a sham condition in a time window ranging from 45 ms to about 200 ms after TMS. Spatial and temporal investigations were carried out with sLORETA. TMS was found to induce propagation of neural activity mainly in the contralateral sensorimotor and frontal cortices, at about 130 ms after delivery of the stimulus. Different types of analyses showed propagated activity also in posterior, mainly visual, regions, in a time window between 70 and 130 ms. Finally, a likely "rebounding" activation of the sensorimotor and frontal regions, was observed in various time ranges. Taken together, the present findings further characterize the neural circuits that are driven by dorsal premotor cortex activation in healthy humans.

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