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4.
Parkinsons Dis ; 2021: 8871549, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34094501

RESUMEN

INTRODUCTION: In a degenerative disorder such as Parkinson's disease (PD), it is important to establish clinical stages that allow to know the course of the disease. Our aim was to analyze whether a scale combining Hoehn and Yahr's motor stage (H&Y) and the nonmotor symptoms burden (NMSB) (assessed by the nonmotor symptoms scale (NMSS)) provides information about the disability and the patient's quality of life (QoL) with regard to a defined clinical stage. MATERIALS AND METHODS: Cross-sectional study in which 603 PD patients from the COPPADIS cohort were classified according to H&Y (1, stage I; 2, stage II; 3, stage III; 4, stage IV/V) and NMSB (A: NMSS = 0-20; B: NMSS = 21-40; C: NMSS = 41-70; D: NMSS ≥ 71) in 16 stages (HY.NMSB, from 1A to 4D). QoL was assessed with the PDQ-39SI, PQ-10, and EUROHIS-QOL8 and disability with the Schwab&England ADL (Activities of Daily Living) scale. RESULTS: A worse QoL and greater disability were observed at a higher stage of H&Y and NMSB (p < 0.0001). Combining both (HY.NMSB), patients in stages 1C and 1D and 2C and 2D had significantly worse QoL and/or less autonomy for ADL than those in stages 2A and 2B and 3A and 3B, respectively (p < 0.005; e.g., PDQ-39SI in 1D [n = 15] vs 2A [n = 101]: 28.6 ± 17.1 vs 7.9 ± 5.8; p < 0.0001). CONCLUSION: The HY.NMSB scale is simple and reflects the degree of patient involvement more accurately than the H&Y. Patients with a lower H&Y stage may be more affected if they have a greater NMS burden.

5.
Int J Geriatr Psychiatry ; 36(5): 627-646, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33169885

RESUMEN

BACKGROUND: Although depression is known to be frequent in Parkinson's disease (PD), it is unclear how mood can change and/or impact on patient's quality of life (QoL) over time. Our aim was to analyze the frequency of depression, mood related factors and the contribution of mood to a patient's QoL perception in regard to disease duration. METHODS: PD patients recruited from the COPPADIS cohort from January 2016 to November 2017 were included in this cross-sectional study. Three groups were defined: <5 years (Group A); from 5 to <10 years (Group B); ≥10 years (Group C). Analysis with well-planned linear regression models was conducted to determine how different factors contribute to mood (Beck Depression Inventory-II [BDI-II] as dependent variable), to health-related QoL (39-item Parkinson's Disease Questionnaire [PDQ-39SI] as dependent variable) and to global QoL (European Health Interview Survey - Quality of Life Eight-Item Index [EUROHIS-QOL8] as dependent variable). RESULTS: Six hundred and sixty-three PD patients (62.6 ± 8.9 years old, 59.6% males) were included: Group A, 50.1% (n = 332); Group B, 33.3% (n = 221) and Group C, 16.6% (n = 110). There were no differences between the three groups in terms of the frequency of depressive symptoms nor the frequency of depression type (major vs. minor vs. subthreshold) (p = 0.729). However, the unique percent variance of PDQ-39SI and EUROHIS-QOL8 explained by BDI-II total score was 2 (23.7%) and threefold (26.9%), respectively, in Group C compared to the other two groups. EUROHIS-QOL8 total score provided the highest unique contribution to mood (16.8%). CONCLUSIONS: Although depression-type frequency does not appear to change over time in PD; the contribution of mood on QoL perception is greater in patients with longer disease duration.


Asunto(s)
Enfermedad de Parkinson , Anciano , Estudios Transversales , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Enfermedad de Parkinson/epidemiología , Calidad de Vida , Encuestas y Cuestionarios
6.
J Neurol Sci ; 418: 117109, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32927370

RESUMEN

BACKGROUND: The role of subthreshold depression (subD) in Parkinson's Disease (PD) is not clear. The present study aimed to compare the quality of life (QoL) in PD patients with subD vs patients with no depressive disorder (nonD). Factors related to subD were identified. MATERIAL AND METHODS: PD patients and controls recruited from the COPPADIS cohort were included. SubD was defined as Judd criteria. The 39-item Parkinson's disease Questionnaire (PDQ-39) and the EUROHIS-QOL 8-item index (EUROHIS-QOL8) were used to assess QoL. RESULTS: The frequency of depressive symptoms was higher in PD patients (n = 694) than in controls (n = 207) (p < 0.0001): major depression, 16.1% vs 7.8%; minor depression, 16.7% vs 7.3%; subD, 17.4% vs 5.8%. Both health-related QoL (PDQ-39; 18.1 ±â€¯12.8 vs 11.6 ±â€¯10; p < 0.0001) and global QoL (EUROHIS-QOL8; 3.7 ±â€¯0.5 vs 4 ±â€¯0.5; p < 0.0001) were significantly worse in subD (n = 120) than nonD (n = 348) PD patients. Non-motor Symptoms Scale (NMSS) total score was higher in subD patients (45.9 ±â€¯32 vs 29.1 ±â€¯25.8;p < 0.0001). Non-motor symptoms burden (NMSS;OR = 1.019;95%CI 1.011-1.028; p < 0.0001), neuropsychiatric symptoms (NPI; OR = 1.091; 95%CI 1.045-1.139; p < 0.0001), impulse control behaviors (QUIP-RS; OR = 1.035; 95%CI 1.007-1063; p = 0.013), quality of sleep (PDSS; OR = 0.991; 95%CI 0.983-0.999; p = 0.042), and fatigue (VAFS-physical; OR = 1.185; 95%CI 1.086-1.293; p < 0.0001; VAFS-mental; OR = 1.164; 95%CI 1.058-1.280; p = 0.0001) were related to subD after adjustment to age, disease duration, daily equivalent levodopa dose, motor status (UPDRS-III), and living alone. CONCLUSIONS: SubD is a frequent problem in patients with PD and is more prevalent in these patients than in controls. QoL is worse and non-motor symptoms burden is greater in subD PD patients.


Asunto(s)
Enfermedad de Parkinson , Calidad de Vida , Depresión/epidemiología , Depresión/etiología , Fatiga/epidemiología , Fatiga/etiología , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/epidemiología , Encuestas y Cuestionarios
7.
Rep Pract Oncol Radiother ; 25(5): 754-759, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32684865

RESUMEN

PURPOSE: Retrospective, single-institution analysis of clinical outcomes and treatment-related toxicity in patients treated with salvage I-125 low-dose rate (LDR) brachytherapy (BT) for locally-recurrent prostate cancer after radiotherapy. MATERIALS AND METHODS: Between 2008 and 2018, 30 patients with biopsy-confirmed prostate cancer recurrence underwent salvage treatment with I-125 LDR-BT. Of these 30 patients, 14 were previously treated with primary external beam radiotherapy (EBRT; median dose, 73 Gy) and 16 with primary I-125 LDR-BT (145 Gy and 160 Gy in 14 and 2 cases, respectively). At seed implantation, the mean age was 75.8 years, with a median Gleason score of 7 and pre-salvage PSA of <10 ng/mL. Six patients received androgen deprivation therapy for six months after relapse diagnosis. The prescribed salvage I-125 BT dose to the gland was 120-130 Gy, with dose restrictions of Dmax <135% (urethra) and <100% (rectum). Toxicity was evaluated according to the CTCAE scale (v4.0). RESULTS: At a median follow-up of 45 months, the biochemical recurrence-free survival rates at 1, 3 and 5 years were 86.7%, 56.7% and 53.3%, respectively. Overall survival at 5 years was 87%. On the multivariate analysis, two variables were significant predictors of recurrence: PSA at relapse and nadir PSA post-salvage. Grade 3 genitourinary toxicity was observed in 5 patients (radiation-induced cystitis in 3 cases and urethral stenosis in 2) and G3 gastrointestinal toxicity in 3 patients (rectal bleeding). CONCLUSION: Salvage therapy with I-125 brachytherapy is a safe and effective treatment option for locally-recurrent prostate cancer in previously-irradiated patients. High pre-salvage PSA and post-salvage nadir PSA values were significantly associated with a worse disease control after salvage I-125 LDR-BT. In well-selected patients, I-125 LDR-BT is comparable to other salvage therapies in terms of disease control and toxicity. However, more research is needed to determine the optimal management of locally-recurrent prostate cancer.

9.
Eur J Neurol ; 26(11): 1399-1407, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31179586

RESUMEN

BACKGROUND AND PURPOSE: In Parkinson's disease (PD), the course of the disorder is highly variable between patients. Well-designed, prospective studies for identifying PD progression biomarkers are necessary. Our aim was to show the results of baseline evaluations of an ongoing global PD project, COPPADIS-2015 (Cohort of Patients with PArkinson's DIsease in Spain, 2015). METHODS: This was an observational, descriptive, nationwide study (Spain). The recruitment period ended in October 2017. Baseline evaluation included more than 15 validated scales and complementary studies in a subgroup of participants. RESULTS: In total, 1174 subjects from 35 centres were considered valid for baseline analysis: 694 patients (62.6 ± 8.9 years old, 60.3% males), 273 caregivers (58.5 ± 11.9 years old, 31.8% males) and 207 controls (61 ± 8.3 years old, 49.5% males). The mean disease duration was 5.5 ± 4.4 years. Hoehn and Yahr stage was 1 or 2 in 90.7% of the patients whilst 33.9% and 18.1% of them presented motor fluctuations and dyskinesias, respectively. The mean Non-Motor Symptoms Scale total score was 45.4 ± 38.1, and 30.4% of the patients presented cognitive impairment, 16.1% major depression, 12.7% impulse control disorder, 7.2% compulsive behaviour, 57.2% pain and 13.2% falls. Compared to the control group, PD patients presented a significantly higher burden of non-motor symptoms and a worse quality of life. More than 300 subjects conducted complementary studies (serum biomarkers, genetic and neuroimaging). CONCLUSIONS: Parkinson's disease is a complex disorder and different non-motor symptoms are frequently present and are more prevalent than in controls. In real clinical practice it is important to ask for them.


Asunto(s)
Enfermedad de Parkinson/patología , Anciano , Anciano de 80 o más Años , Cuidadores/estadística & datos numéricos , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/etiología , Estudios de Cohortes , Comorbilidad , Progresión de la Enfermedad , Trastornos Disruptivos, del Control de Impulso y de la Conducta , Femenino , Humanos , Estudios Longitudinales , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/etiología , Persona de Mediana Edad , Trastornos del Movimiento/epidemiología , Trastornos del Movimiento/etiología , Enfermedad de Parkinson/epidemiología , Enfermedad de Parkinson/psicología , Estudios Prospectivos , Calidad de Vida , Factores Socioeconómicos , España/epidemiología
10.
Rev Neurol ; 66(5): 163-172, 2018 Mar 01.
Artículo en Español | MEDLINE | ID: mdl-29480513

RESUMEN

INTRODUCTION: Botulinum toxin type A (BTA) is a bacterial endotoxin, whose therapeutic use has had a dramatic impact on different neurological disorders, such as dystonia and spasticity. AIM: To analyze and summarize different questions about the use of BTA in our clinical practice. DEVELOPMENT: A group of experts in neurology developed a list of topics related with the use of BTA. Two groups were considered: neuropharmacology and dystonia. A literature search at PubMed, mainly for English language articles published up to June 2016 was performed. The manuscript was structured as a questionnaire that includes those questions that, according to the panel opinion, could generate more controversy or doubt. The initial draft was reviewed by the expert panel members to allow modifications, and after subsequent revisions for achieving the highest degree of consensus, the final text was then validated. Different questions about diverse aspects of neuropharmacology, such as mechanism of action, bioequivalence of the different preparations, immunogenicity, etc. were included. Regarding dystonia, the document included questions about methods of evaluation, cervical dystonia, blepharospasm, etc. CONCLUSION: This review does not pretend to be a guide, but rather a tool for continuous training of residents and specialists in neurology, about different specific areas of the management of BTA.


TITLE: Mitos y evidencias en el empleo de la toxina botulinica: neurofarmacologia y distonias.Introduccion. La toxina botulinica de tipo A (TBA) ha supuesto una verdadera revolucion terapeutica en neurologia, y en la actualidad es el tratamiento rutinario en las distonias focales y la espasticidad. Objetivo. Plantear, revisar y responder cuestiones controvertidas en relacion con la neurofarmacologia de la TBA y su uso en las distonias en la practica clinica habitual. Desarrollo. Un grupo de expertos en trastornos del movimiento reviso una lista de temas controvertidos relacionados con la farmacologia de la TBA y su uso en las distonias. Revisamos la bibliografia e incluimos articulos relevantes especialmente en ingles, pero tambien, si su importancia lo merece, en castellano y en frances, hasta junio de 2016. El documento se estructuro como un cuestionario que incluyo las preguntas que podrian generar mayor controversia o duda. El borrador inicial del documento fue revisado por los miembros del panel y se realizaron las modificaciones necesarias hasta alcanzar el mayor grado de consenso. Incluimos preguntas sobre diferentes aspectos de la neurofarmacologia, especialmente el mecanismo de accion, la bioequivalencia de los diferentes preparados y la inmunogenicidad. En relacion con el subapartado de las distonias, se incluyeron aspectos sobre la evaluacion y el tratamiento de las distonias focales. Conclusiones. Esta revision no pretende ser una guia, sino una herramienta practica destinada a neurologos y medicos internos residentes interesados en esta area, dentro de diferentes ambitos especificos del manejo de la TBA.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Trastornos Distónicos/tratamiento farmacológico , Antitoxina Botulínica/biosíntesis , Toxinas Botulínicas Tipo A/efectos adversos , Toxinas Botulínicas Tipo A/inmunología , Toxinas Botulínicas Tipo A/farmacología , Manejo de la Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Resistencia a Medicamentos , Estabilidad de Medicamentos , Trastornos Distónicos/diagnóstico por imagen , Humanos , Espasticidad Muscular/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Equivalencia Terapéutica
11.
ACS Catal ; 7(8): 5268-5281, 2017 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-28824823

RESUMEN

The selectivity toward lower olefins during the methanol-to-olefins conversion over H-SAPO-34 at reaction temperatures between 573 and 773 K has been studied with a combination of operando UV-vis diffuse reflectance spectroscopy and online gas chromatography. It was found that the selectivity toward propylene increases in the temperature range of 573-623 K, while it decreases in the temperature range of 623-773 K. The high degree of incorporation of olefins, mainly propylene, into the hydrocarbon pool affects the product selectivity at lower reaction temperatures. The nature and dynamics of the active and deactivating hydrocarbon species with increasing reaction temperature were revealed by a non-negative matrix factorization of the time-resolved operando UV-vis diffuse reflectance spectra. The active hydrocarbon pool species consist of mainly highly methylated benzene carbocations at temperatures between 573 and 598 K, of both highly methylated benzene carbocations and methylated naphthalene carbocations at 623 K, and of only methylated naphthalene carbocations at temperatures between 673 and 773 K. The operando spectroscopy results suggest that the nature of the active species also influences the olefin selectivity. In fact, monoenylic and highly methylated benzene carbocations are more selective to the formation of propylene, whereas the formation of the group of low methylated benzene carbocations and methylated naphthalene carbocations at higher reaction temperatures (i.e., 673 and 773 K) favors the formation of ethylene. At reaction temperatures between 573 and 623 K, catalyst deactivation is caused by the gradual filling of the micropores with methylated naphthalene carbocations, while between 623 and 773 K the formation of neutral poly aromatics and phenanthrene/anthracene carbocations are mainly responsible for catalyst deactivation, their respective contribution increasing with increasing reaction temperature. Methanol pulse experiments at different temperatures demonstrate the dynamics between methylated benzene and methylated naphthalene carbocations. It was found that methylated naphthalene carbocations species are deactivating and block the micropores at low reaction temperatures, while acting as the active species at higher reaction temperatures, although they give rise to the formation of extended hydrocarbon deposits.

13.
Eur J Neurol ; 24(2): 427-e6, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28102045

RESUMEN

BACKGROUND AND PURPOSE: The presentation of Parkinson's disease patients with mutations in the LRRK2 gene (PDLRRK2 ) is highly variable, suggesting a strong influence of modifying factors. In this context, inflammation is a potential candidate inducing clinical subtypes. METHODS: An extensive battery of peripheral inflammatory markers was measured in human serum in a multicentre cohort of 142 PDLRRK2 patients from the MJFF LRRK2 Consortium, stratified by three different subtypes as recently proposed for idiopathic Parkinson's disease: diffuse/malignant, intermediate and mainly pure motor. RESULTS: Patients classified as diffuse/malignant presented with the highest levels of the pro-inflammatory proteins interleukin 8 (IL-8), monocyte chemotactic protein 1 (MCP-1) and macrophage inflammatory protein 1-ß (MIP-1-ß) paralleled by high levels of the neurotrophic protein brain-derived neurotrophic factor (BDNF). It was also possible to distinguish the clinical subtypes based on their inflammatory profile by using discriminant and area under the receiver operating characteristic curve analysis. CONCLUSIONS: Inflammation seems to be associated with the presence of a specific clinical subtype in PDLRRK2 that is characterized by a broad and more severely affected spectrum of motor and non-motor symptoms. The pro-inflammatory metabolites IL-8, MCP-1 and MIP-1-ß as well as BDNF are interesting candidates to be included in biomarker panels that aim to differentiate subtypes in PDLRRK2 and predict progression.


Asunto(s)
Inflamación/etiología , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/patología , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Factor Neurotrófico Derivado del Encéfalo/sangre , Quimiocina CCL2/sangre , Quimiocina CCL4/sangre , Estudios de Cohortes , Citocinas/sangre , Progresión de la Enfermedad , Femenino , Humanos , Inflamación/genética , Inflamación/patología , Masculino , Persona de Mediana Edad , Mutación
17.
Parkinsonism Relat Disord ; 20(10): 1097-100, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25127457

RESUMEN

OBJECTIVE: The neuropsychological characteristics of patients with Parkinson's Disease (PD) associated with R1441G mutation in the LRRK2 gene (R1441G-PD) are not well known. The aim of this study was to examine the cognitive status and mood of R1441G-PD patients. METHODS: Thirty patients with R1441G-PD were compared with thirty idiopathic PD (i-PD) patients who were matched by age, sex, education, disease onset age and duration, using a comprehensive battery of neuropsychological test, and considering the Movement Disorder Society (MDS) criteria for the diagnosis of Mild Cognitive Impairment (PD-MCI) and dementia (PD-Dementia). RESULTS: The mean scores in the depression and anxiety scales were similar in the two groups. Depressive symptoms were detected in 31.8% of R1441G-PD and 25% of i-PD patients and anxiety symptoms were evident in 4.5% and 15%, respectively, but the differences were not significant. The only neuropsychological test on which there was a significantly worse performance in the R1441G-PD group was the Boston naming test but the difference became not significant when Bonferroni's correction was applied. The prevalence of PD-MCI was 30% in both R1441G-PD and i-PD, with no differences in the number and type of domains altered given that executive function, memory and attention were mainly affected. PD-Dementia was diagnosed in 13.3% (n = 4) of R1441G-PD and 26.7% (n = 8) of i-PD patients (difference was not significant). CONCLUSION: In conclusion, significant differences were not detected between R1441G-PD and i-PD in cognitive, depression and anxiety scales, or PD-MCI and PD-Dementia prevalence, and the cognitive profile was identical in the two groups.


Asunto(s)
Trastornos del Conocimiento/etiología , Mutación/genética , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/genética , Proteínas Serina-Treonina Quinasas/genética , Adulto , Anciano , Anciano de 80 o más Años , Arginina/genética , Estudios de Casos y Controles , Trastornos del Conocimiento/genética , Femenino , Glicina/genética , Humanos , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Índice de Severidad de la Enfermedad
18.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 33(4): 215-226, jul.-ago. 2014. tab, ilus
Artículo en Español | IBECS | ID: ibc-125257

RESUMEN

Las técnicas de neuroimagen funcional se han utilizado tradicionalmente en la investigación de los pacientes que presentan un síndrome parkinsoniano. Sin embargo, la aparición de radiofármacos comerciales junto a la disponibilidad de equipos de tomografía por emisión de fotón único (SPECT) y más recientemente de la tomografía por emisión de positrones (PET), han permitido su empleo rutinario en la práctica clínica. Precisamente el desarrollo y grado de evidencia clínica alcanzado por los biomarcadores de neuroimagen durante las 2 últimas décadas ha conllevado que progresivamente se estén incluyendo en los criterios clínicos de diagnóstico de enfermedades neurodegenerativas que cursan con un síndrome parkinsoniano. No obstante, la diversidad de radiofármacos que permiten evaluar la funcionalidad de las vías anatómicas involucradas en la neurodegeneración presente en los diferentes síndromes parkinsonianos (vía nigroestriatal dopaminérgica, actividad neuronal de los ganglios basales y la corteza, inervación simpática miocárdica), junto a las técnicas de neuroimagen (gammagrafía, SPECT y PET) han originado cierta controversia con respecto a la indicación de las pruebas de neuroimagen como exploración complementaria. En esta revisión realizada por un panel de expertos en medicina nuclear y neurología se analizan las técnicas de neuroimagen funcional disponibles haciendo especial énfasis en las consideraciones prácticas del diagnóstico de pacientes con un síndrome parkinsoniano de origen incierto y la valoración de la progresión de la enfermedad de Parkinson (AU)


Functional Neuroimaging has been traditionally used in research for patients with different Parkinsonian syndromes. However, the emergence of commercial radiotracers together with the availability of single photon emission computed tomography (SPECT) and, more recently, positron emission tomography (PET) have made them available for clinical practice. Particularly, the development of clinical evidence achieved by functional neuroimaging techniques over the past two decades have motivated a progressive inclusion of several biomarkers in the clinical diagnostic criteria for neurodegenerative diseases that occur with Parkinsonism. However, the wide range of radiotracers designed to assess the involvement of different pathways in the neurodegenerative process underlying Parkinsonian syndromes (dopaminergic nigrostriatal pathway integrity, basal ganglia and cortical neuronal activity, myocardial sympathetic innervation), and the different neuroimaging techniques currently available (scintigraphy, SPECT and PET), have generated some controversy concerning the best neuroimaging test that should be indicated for the differential diagnosis of Parkinsonism. In this article, a panel of nuclear medicine and neurology experts has evaluated the functional neuroimaging techniques emphazising practical considerations related to the diagnosis of patients with uncertain origin parkinsonism and the assessment Parkinson’s disease progression (AU)


Asunto(s)
Humanos , Trastornos Parkinsonianos , Neuroimagen Funcional/métodos , Enfermedad de Parkinson , Cintigrafía/métodos , Diagnóstico Diferencial , Tomografía de Emisión de Positrones , Receptores Dopaminérgicos/fisiología , Tomografía Computarizada de Emisión de Fotón Único/métodos
19.
Rev Esp Med Nucl Imagen Mol ; 33(4): 215-26, 2014.
Artículo en Español | MEDLINE | ID: mdl-24731551

RESUMEN

Functional Neuroimaging has been traditionally used in research for patients with different Parkinsonian syndromes. However, the emergence of commercial radiotracers together with the availability of single photon emission computed tomography (SPECT) and, more recently, positron emission tomography (PET) have made them available for clinical practice. Particularly, the development of clinical evidence achieved by functional neuroimaging techniques over the past two decades have motivated a progressive inclusion of several biomarkers in the clinical diagnostic criteria for neurodegenerative diseases that occur with Parkinsonism. However, the wide range of radiotracers designed to assess the involvement of different pathways in the neurodegenerative process underlying Parkinsonian syndromes (dopaminergic nigrostriatal pathway integrity, basal ganglia and cortical neuronal activity, myocardial sympathetic innervation), and the different neuroimaging techniques currently available (scintigraphy, SPECT and PET), have generated some controversy concerning the best neuroimaging test that should be indicated for the differential diagnosis of Parkinsonism. In this article, a panel of nuclear medicine and neurology experts has evaluated the functional neuroimaging techniques emphazising practical considerations related to the diagnosis of patients with uncertain origin parkinsonism and the assessment Parkinson's disease progression.


Asunto(s)
Neuroimagen Funcional , Trastornos Parkinsonianos/diagnóstico por imagen , Tomografía de Emisión de Positrones , Tomografía Computarizada de Emisión de Fotón Único , Algoritmos , Diagnóstico Diferencial , Humanos , Guías de Práctica Clínica como Asunto
20.
J Colloid Interface Sci ; 383(1): 148-54, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-22796067

RESUMEN

Ni-based catalysts supported on Zn-modified alumina were investigated in the ethanol steam reforming reaction. A commercial γ-alumina was impregnated with different amounts of zinc nitrate (0, 2, 5, 10, 15, 20 wt.% on Zn basis), calcined, and then impregnated with nickel nitrate aqueous solutions. The samples were characterized by a number of techniques: N(2) adsorption at 77 K, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray fluorescence (XRF), and temperature-programmed reduction (TPR). Their catalytic behavior in the ethanol steam reforming reaction was studied at 873 K, with a H(2)O/ethanol ratio of 5:1. Two effects of the presence of Zn were detected. On the one hand, zinc modifies the surface structure and the surface chemistry of the catalysts by formation of zinc aluminates, and on the other hand, zinc oxide can be reduced to metallic zinc under reaction conditions, thus modifying the catalytic properties of the active phase. The presence of Zn increases the ethanol conversion to gaseous compounds as compared with the catalyst supported on the Zn-free commercial alumina. The addition of a small amount of Pt (1 wt.%) causes a beneficial effect in the reaction. When Ni catalysts were used without a previous reduction treatment, ethylene was formed in high amounts; however, the Pt-Ni catalysts need no reduction pre-treatment to achieve high H(2) yields (close to 70%) and showed a high stability versus time on stream because of the control of the production of ethylene, a coke precursor.

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