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1.
Muscle Nerve ; 62(1): 10-12, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32337730

RESUMEN

Modern neuromuscular electrodiagnosis (EDX) and neuromuscular ultrasound (NMUS) require a universal language for effective communication in clinical practice and research and, in particular, for teaching young colleagues. Therefore, the AANEM and the IFCN have decided to publish a joint glossary as they feel the need for an updated terminology to support educational activities in neuromuscular EDX and NMUS in all parts of the world. In addition NMUS has been rapidly progressing over the last years and is now widely used in the diagnosis of disorders of nerve and muscle in conjunction with EDX. This glossary has been developed by experts in the field of neuromuscular EDX and NMUS on behalf of the AANEM and the IFCN and has been agreed upon by electronic communication between January and November 2019. It is based on the glossaries of the AANEM from 2015 and of the IFCN from 1999. The EDX and NMUS terms and the explanatory illustrations have been updated and supplemented where necessary. The result is a comprehensive glossary of terms covering all fields of neuromuscular EDX and NMUS. It serves as a standard reference for clinical practice, education and research worldwide. HIGHLIGHTS: Optimal terminology in neuromuscular electrodiagnosis and ultrasound has been revisited. A team of international experts have revised and expanded a standardized glossary. This list of terms serves as standard reference for clinical practice, education and research.


Asunto(s)
Diccionarios como Asunto , Electrodiagnóstico/clasificación , Enfermedades Neuromusculares/clasificación , Enfermedades Neuromusculares/diagnóstico por imagen , Sociedades Médicas/clasificación , Ultrasonografía/clasificación , Humanos , Estados Unidos
2.
Muscle Nerve ; 59(5): 567-576, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30734322

RESUMEN

INTRODUCTION: We sought to identify patients with amyotrophic lateral sclerosis (ALS) who displayed suspected peripheral nervous system (PNS) inflammation to compare them to those with suspected PNS degeneration. METHODS: We measured sonographic median and ulnar nerve cross-sectional area (CSA) and cerebrospinal fluid albumin/serum albumin ratio (Qalb ) in patients with ALS to classify them as having suspected PNS degeneration (small CSA/low Qalb ) or inflammation (larger CSA/high Qalb ). RESULTS: Fifty-seven percent of patients had suspected PNS degeneration, 21% had suspected PNS inflammation, and 21% displayed suspected "normal PNS state." Suspected PNS degeneration was related to classic ALS, shorter disease duration, and a smaller hypoechoic nerve area. Suspected PNS inflammation was associated with men, longer disease duration, and a larger hypoechoic nerve area and was the dominant finding in superoxide dismutase 1 mutation carriers. DISCUSSION: Our simple approach might aid in the in vivo differentiation of supposed ALS subtypes, those with suspected PNS degeneration vs. inflammation, for stratification in clinical trials. Muscle Nerve 59:567-567, 2019.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Nervio Mediano/diagnóstico por imagen , Nervio Cubital/diagnóstico por imagen , Anciano , Albúminas/líquido cefalorraquídeo , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/inmunología , Femenino , Humanos , Inflamación/diagnóstico por imagen , Masculino , Nervio Mediano/patología , Persona de Mediana Edad , Mutación , Tamaño de los Órganos , Sistema Nervioso Periférico/diagnóstico por imagen , Sistema Nervioso Periférico/inmunología , Curva ROC , Albúmina Sérica , Superóxido Dismutasa-1/genética , Nervio Cubital/patología , Ultrasonografía
3.
Health Qual Life Outcomes ; 17(1): 95, 2019 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-31159830

RESUMEN

BACKGROUND: Dyspnea is frequent in amyotrophic lateral sclerosis (ALS) and one of the most bothersome symptoms. The recently developed Dyspnea-ALS-Scale (DALS-15) is a disease-specific patient-reported outcome to detect and quantify dyspnea. OBJECTIVES: To analyze in a case-based approach the diagnostic and clinical implications and the benefit of the DALS-15 for individual patients in daily clinical routine. METHODS: Dyspnea was assessed by the 15-item comprising DALS-15 in two patients with ALS. Spirometry was performed and blood gases were analyzed. Results were evaluated in the clinical context of the respective patients. RESULTS: In one patient the presence of dyspnea detected by the DALS-15 indicated noninvasive ventilation (NIV) although forced vital capacity (FVC) and blood gas analysis were well preserved. After NIV implementation, the DALS-15 was helpful to determine the patient's need for medication, the timing of NIV titration and the adaptation of NIV sessions. In another patient, who was anarthric and no longer able to perform spirometry due to severe bulbar impairment, the DALS-15 allowed a standardized assessment of dyspnea-related distress independently of bulbar dysfunction. CONCLUSION: The DALS-15 provides a deeper insight into the respiratory status of individual patients. It helps to diagnose respiratory impairment in patients in whom NIV should be considered although FVC and blood gas results do not reveal indication for NIV. It is also valuable for the guidance of patients in later stages of respiratory impairment when NIV is already implemented, and in patients with severe bulbar dysfunction. The DALS-15 can improve specific symptom management and coordination of care and therefore has the potential to optimize individual treatment in ALS patients with dyspnea.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Disnea/diagnóstico , Medición de Resultados Informados por el Paciente , Calidad de Vida , Insuficiencia Respiratoria/diagnóstico , Anciano , Esclerosis Amiotrófica Lateral/complicaciones , Esclerosis Amiotrófica Lateral/terapia , Progresión de la Enfermedad , Disnea/etiología , Disnea/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia
4.
Radiology ; 289(1): 195-203, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30040038

RESUMEN

Purpose To investigate the whole-brain landscape of iron-related abnormalities in amyotrophic lateral sclerosis (ALS) by using the in vivo MRI technique of quantitative susceptibility mapping (QSM). Materials and Methods For this prospective study, 28 patients with ALS (mean age, 61 years; age range, 43-77 years; 18 men [mean age, 61 years; range, 43-77 years] and 10 women [mean age, 61 years; range, 47-74 years]) recruited between January 17, 2014, and September 4, 2015, and 39 matched control subjects (mean age, 61 years; age range, 39-77 years; 24 men [mean age, 62 years; range, 39-77 years] and 15 women [mean age, 59 years; range, 39-73 years]) were examined by using structural and susceptibility 3.0-T MRI techniques. Group data were cross sectionally compared with family-wise error (FWE) corrections by using voxel-based morphometry (random-field theory), cortical thickness analysis (Monte Carlo simulated), subcortical volumetry (Bonferroni-corrected Wilcoxon rank-sum testing), and QSM analysis (cluster-enhanced whole-brain permutation testing and Bonferroni-corrected rank-sum testing in regions of interest). In patients with ALS, a potential relationship between diffusion and susceptibility measurements in the corticospinal tracts (CSTs) was also examined by using Spearman rank-correlation tests. Results Conventional structural measures failed to identify atrophy in the present cohort (FWE P > .05). However, QSM identified several whole-brain abnormalities (FWE P < .05) in ALS. Regionally, higher susceptibility (expressed as means in parts per million ± standard errors of the mean) was confirmed in the motor cortex (ALS = 0.0188 ± 0.0003, control = 0.0173 ± 0.0003; P < .001), the left substantia nigra (ALS = 0.127 ± 0.004, control = 0.113 ± 0.003; P = .008), the right substantia nigra (ALS = 0.141 ± 0.005, control = 0.120 ± 0.003; P < .001), the globus pallidus (ALS = 0.086 ± 0.003, control = 0.075 ± 0.002; P = .003), and the red nucleus (ALS = 0.115 ± 0.004, control = 0.098 ± 0.003; P < .001). Lower susceptibility was found in CST white matter (ALS = -0.047 ± 0.001, control = -0.043 ± 0.001; P = .01). Nigral and pallidal QSM values were cross correlated in ALS (ρ2 = 0.42, P < .001), a phenomenon visually traceable in many individual patients. QSM in the CST in ALS also correlated with diffusion-tensor metrics in this tract (ρ2 = 0.25, P = .007). Conclusion Whole-brain MRI quantitative susceptibility mapping analysis is sensitive to tissue alterations in amyotrophic lateral sclerosis that may be relevant to pathologic changes. © RSNA, 2018.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Hierro/análisis , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Química Encefálica/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
5.
Muscle Nerve ; 57(2): 273-278, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28472860

RESUMEN

INTRODUCTION: We aimed to investigate whether sonographic peripheral cross-sectional nerve area (CSA) and progranulin (PGRN), a neuritic growth factor, are related to each other and whether they interact to predict clinical and paraclinical measures in amyotrophic lateral sclerosis (ALS). METHODS: We included 55 ALS patients who had forearm median and ulnar nerve CSA, cerebrospinal fluid (CSF) PGRN, and serum PGRN measures available. CSF PGRN was normalized against the CSF / serum albumin ratio (Qalb ). Using age, sex, height, and weight adjusted general linear models, we examined CSA × CSF PGRN interaction effects on various measures. RESULTS: There was a medium-effect size inverse relationship between CSA and CSF PGRN, but not between CSA and serum PGRN. Lower CSA values together with higher CSF PGRN levels were linked to smaller motor amplitudes. DISCUSSION: In ALS, the constellation of peripheral nerve atrophy together with higher CSF PGRN levels indicates pronounced axonal damage. Muscle Nerve 57: 273-278, 2018.


Asunto(s)
Esclerosis Amiotrófica Lateral/líquido cefalorraquídeo , Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Axones/ultraestructura , Enfermedades del Sistema Nervioso Periférico/diagnóstico por imagen , Progranulinas/líquido cefalorraquídeo , Adulto , Anciano , Anatomía Transversal , Atrofia , Biomarcadores , Estudios Transversales , Fenómenos Electrofisiológicos , Femenino , Antebrazo/diagnóstico por imagen , Antebrazo/inervación , Humanos , Masculino , Nervio Mediano/diagnóstico por imagen , Persona de Mediana Edad , Estudios Prospectivos , Nervio Cubital/diagnóstico por imagen , Ultrasonografía
6.
Neuroimage ; 152: 390-399, 2017 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-28288908

RESUMEN

Experimental research has shown that the centromedian-parafascicular complex (CM-Pf) of the intralaminar thalamus is activated in attentional orienting and processing of behaviorally relevant stimuli. These observations resulted in the hypothesis that the CM-Pf plays a pivotal role in goal-oriented behavior selection. We here set out to test this hypothesis with electrophysiological recordings from patients with electrodes implanted in CM-Pf for deep brain stimulation (DBS) treatment of chronic neuropathic pain. Six patients participated in (1) an auditory three-class oddball experiment, which required a button press to target tones, but not to standard and deviant tones and in (2) a multi-speaker experiment with a target word that required attention selection and a target image that required response selection. Subjects showed transient neural responses (8-15Hz) to the target tone and the target word. Two subjects additionally showed transient neural responses (15-25Hz) to the target image. All sensory target stimuli were related to an internal goal and required a behavior selection (attention selection, response selection). In group analyses, neural responses were greater to target tones than deviant and standard tones and to target words than other task-relevant words that did not require attention selection. The transient neural responses occurred after the target stimuli but prior to the overt behavioral response. Our results demonstrate that in human subjects the CM-Pf is involved in signaling sensory inputs related to goal-oriented selection of behavior.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Señales (Psicología) , Núcleos Talámicos Intralaminares/fisiología , Desempeño Psicomotor , Estimulación Acústica , Adulto , Femenino , Objetivos , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción
7.
Hum Brain Mapp ; 38(4): 2206-2225, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28130910

RESUMEN

There is substantial variability in speech recognition ability across patients with cochlear implants (CIs), auditory brainstem implants (ABIs), and auditory midbrain implants (AMIs). To better understand how this variability is related to central processing differences, the current electroencephalography (EEG) study compared hearing abilities and auditory-cortex activation in patients with electrical stimulation at different sites of the auditory pathway. Three different groups of patients with auditory implants (Hannover Medical School; ABI: n = 6, CI: n = 6; AMI: n = 2) performed a speeded response task and a speech recognition test with auditory, visual, and audio-visual stimuli. Behavioral performance and cortical processing of auditory and audio-visual stimuli were compared between groups. ABI and AMI patients showed prolonged response times on auditory and audio-visual stimuli compared with NH listeners and CI patients. This was confirmed by prolonged N1 latencies and reduced N1 amplitudes in ABI and AMI patients. However, patients with central auditory implants showed a remarkable gain in performance when visual and auditory input was combined, in both speech and non-speech conditions, which was reflected by a strong visual modulation of auditory-cortex activation in these individuals. In sum, the results suggest that the behavioral improvement for audio-visual conditions in central auditory implant patients is based on enhanced audio-visual interactions in the auditory cortex. Their findings may provide important implications for the optimization of electrical stimulation and rehabilitation strategies in patients with central auditory prostheses. Hum Brain Mapp 38:2206-2225, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Corteza Auditiva/fisiopatología , Tronco Encefálico/fisiopatología , Enfermedades Cocleares/patología , Enfermedades Cocleares/fisiopatología , Electroencefalografía , Estimulación Acústica , Adulto , Anciano , Corteza Auditiva/diagnóstico por imagen , Vías Auditivas/diagnóstico por imagen , Vías Auditivas/fisiopatología , Tronco Encefálico/diagnóstico por imagen , Tronco Encefálico/cirugía , Enfermedades Cocleares/diagnóstico por imagen , Enfermedades Cocleares/cirugía , Implantación Coclear/métodos , Implantes Cocleares , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Patrones de Reconocimiento Fisiológico , Estimulación Luminosa , Tiempo de Reacción/fisiología
8.
Stem Cells ; 34(6): 1563-75, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26946488

RESUMEN

Despite decades of research on amyotrophic lateral sclerosis (ALS), there is only one approved drug, which minimally extends patient survival. Here, we investigated pathophysiological mechanisms underlying ALS using motor neurons (MNs) differentiated from induced pluripotent stem cells (iPSCs) derived from ALS patients carrying mutations in FUS or SOD1. Patient-derived MNs were less active and excitable compared to healthy controls, due to reduced Na(+) /K(+) ratios in both ALS groups accompanied by elevated potassium channel (FUS) and attenuated sodium channel expression levels (FUS, SOD1). ALS iPSC-derived MNs showed elevated endoplasmic reticulum stress (ER) levels and increased caspase activation. Treatment with the FDA approved drug 4-Aminopyridine (4AP) restored ion-channel imbalances, increased neuronal activity levels and decreased ER stress and caspase activation. This study provides novel pathophysiological data, including a mechanistic explanation for the observed hypoexcitability in patient-derived MNs and a new therapeutic strategy to provide neuroprotection in MNs affected by ALS. Stem Cells 2016;34:1563-1575.


Asunto(s)
4-Aminopiridina/farmacología , Esclerosis Amiotrófica Lateral/patología , Células Madre Pluripotentes Inducidas/patología , Neuronas Motoras/patología , Esclerosis Amiotrófica Lateral/genética , Caspasas/metabolismo , Diferenciación Celular/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Canales Iónicos/metabolismo , Masculino , Persona de Mediana Edad , Mutación/genética , Neuroprotección/efectos de los fármacos , Fenotipo , Proteína FUS de Unión a ARN/genética , Superóxido Dismutasa/genética , Sinapsis/efectos de los fármacos , Sinapsis/metabolismo
9.
Brain ; 139(Pt 4): 1106-22, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26984187

RESUMEN

Amyotrophic lateral sclerosis, the most common adult-onset motor neuron disease, leads to death within 3 to 5 years after onset. Beyond progressive motor impairment, patients with amyotrophic lateral sclerosis suffer from major defects in energy metabolism, such as weight loss, which are well correlated with survival. Indeed, nutritional intervention targeting weight loss might improve survival of patients. However, the neural mechanisms underlying metabolic impairment in patients with amyotrophic lateral sclerosis remain elusive, in particular due to the lack of longitudinal studies. Here we took advantage of samples collected during the clinical trial of pioglitazone (GERP-ALS), and characterized longitudinally energy metabolism of patients with amyotrophic lateral sclerosis in response to pioglitazone, a drug with well-characterized metabolic effects. As expected, pioglitazone decreased glycaemia, decreased liver enzymes and increased circulating adiponectin in patients with amyotrophic lateral sclerosis, showing its efficacy in the periphery. However, pioglitazone did not increase body weight of patients with amyotrophic lateral sclerosis independently of bulbar involvement. As pioglitazone increases body weight through a direct inhibition of the hypothalamic melanocortin system, we studied hypothalamic neurons producing proopiomelanocortin (POMC) and the endogenous melanocortin inhibitor agouti-related peptide (AGRP), in mice expressing amyotrophic lateral sclerosis-linked mutant SOD1(G86R). We observed lower Pomc but higher Agrp mRNA levels in the hypothalamus of presymptomatic SOD1(G86R) mice. Consistently, numbers of POMC-positive neurons were decreased, whereas AGRP fibre density was elevated in the hypothalamic arcuate nucleus of SOD1(G86R) mice. Consistent with a defect in the hypothalamic melanocortin system, food intake after short term fasting was increased in SOD1(G86R) mice. Importantly, these findings were replicated in two other amyotrophic lateral sclerosis mouse models based on TDP-43 (Tardbp) and FUS mutations. Finally, we demonstrate that the melanocortin defect is primarily caused by serotonin loss in mutant SOD1(G86R) mice. Altogether, the current study combined clinical evidence and experimental studies in rodents to provide a mechanistic explanation for abnormalities in food intake and weight control observed in patients with amyotrophic lateral sclerosis. Importantly, these results also show that amyotrophic lateral sclerosis progression impairs responsiveness to classical drugs leading to weight gain. This has important implications for pharmacological management of weight loss in amyotrophic lateral sclerosis.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Hipotálamo/metabolismo , Proopiomelanocortina/metabolismo , Transducción de Señal/fisiología , Superóxido Dismutasa/metabolismo , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Esclerosis Amiotrófica Lateral/genética , Animales , Femenino , Humanos , Hipotálamo/efectos de los fármacos , Hipotálamo/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Pioglitazona , Proopiomelanocortina/genética , Riluzol/farmacología , Riluzol/uso terapéutico , Transducción de Señal/efectos de los fármacos , Superóxido Dismutasa/genética , Superóxido Dismutasa-1 , Tiazolidinedionas/farmacología , Tiazolidinedionas/uso terapéutico
10.
Muscle Nerve ; 54(3): 391-7, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26840391

RESUMEN

INTRODUCTION: In this study we investigated whether peripheral nerve sonography could be used as a biomarker to monitor disease progression in amyotrophic lateral sclerosis (ALS). METHODS: In 37 patients, ulnar and median nerve cross-sectional area (CSA) was determined in at least 2 ultrasound sessions; mean follow-up was 14.5 months. Linear mixed-effects models were conducted to analyze time effects on CSA. RESULTS: Ulnar nerve CSA declined significantly at a monthly rate of -0.04 mm(2) (forearm) and -0.05 mm(2) (wrist); the decrease was more pronounced when baseline CSA was greater. To detect a 50% treatment effect on ulnar nerve CSA, 332 patients would need to be entered in a hypothetical randomized, controlled clinical trial. Time had no significant impact on median nerve CSA. CONCLUSIONS: Distal ulnar nerve ultrasound may be a useful biomarker to monitor disease progression in ALS, especially as hypothetical treatment effects on CSA seem to be detectable in manageable cohort sizes. Muscle Nerve 54: 391-397, 2016.


Asunto(s)
Esclerosis Amiotrófica Lateral , Nervios Periféricos/diagnóstico por imagen , Nervios Periféricos/fisiopatología , Ultrasonografía/métodos , Anciano , Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Esclerosis Amiotrófica Lateral/patología , Esclerosis Amiotrófica Lateral/fisiopatología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Antebrazo/inervación , Humanos , Masculino , Persona de Mediana Edad , Conducción Nerviosa/fisiología , Muñeca/inervación
11.
J Int Neuropsychol Soc ; 22(6): 662-70, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27333537

RESUMEN

Objectives Although primary dystonia is typically characterized as a movement disorder, it is also associated with cognitive alterations in the domain of executive functioning which may arise from changes in cortico-basal ganglia circuits. Specifically, in comparison to healthy controls, patients with dystonia show deficits in neuropsychological tests of cognitive flexibility. However, it is unclear whether cognitive inflexibility is caused by the pathomechanisms underlying primary dystonia or by confounding factors such as depression or symptom-related distraction.Methods The present study aimed to eliminate these confounds by examining cognitive flexibility in dystonia patients and in patients with similar motor symptoms but without a comparable central pathophysiology. Eighteen patients with primary blepharospasm, a common form of dystonia affecting the muscles around the eyes, and 19 patients with hemifacial spasm, a facial nerve disorder causing similar eyelid spasms, completed a computerized version of the Wisconsin Card Sorting Test (cWCST). The two groups were further compared on tests of global cognitive functioning, psychiatric symptoms, health status, and impulsiveness. Results Blepharospasm patients committed significantly more errors on the cWCST than patients with hemifacial spasm. Group differences were most pronounced with regard to integration errors, a measure of rule-inference processes on the cWCST. Integration errors were also associated with impulsiveness in patients with blepharospasm. Conclusions Primary blepharospasm is related to deficits in cognitive flexibility, even when blepharospasm patients are compared with patients who suffer from motor symptoms of non-dystonic origin. Our results support the possibility that cognitive inflexibility results from the specific pathophysiological processes underlying primary dystonia. (JINS, 2016, 22, 662-670).


Asunto(s)
Blefaroespasmo/fisiopatología , Disfunción Cognitiva/fisiopatología , Trastornos Distónicos/fisiopatología , Función Ejecutiva/fisiología , Espasmo Hemifacial/fisiopatología , Anciano , Blefaroespasmo/complicaciones , Disfunción Cognitiva/etiología , Trastornos Distónicos/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad
12.
Brain Cogn ; 106: 78-89, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27266394

RESUMEN

The human brain predicts events in its environment based on expectations, and unexpected events are surprising. When probabilistic contingencies in the environment are precisely instructed, the individual can form expectations based on quantitative probabilistic information ('inference-based learning'). In contrast, when probabilistic contingencies are imprecisely instructed, expectations are formed based on the individual's cumulative experience ('experience-based learning'). Here, we used the urn-ball paradigm to investigate how variations in prior probabilities and in the precision of information about these priors modulate choice behavior and event-related potential (ERP) correlates of surprise. In the urn-ball paradigm, participants are repeatedly forced to infer hidden states responsible for generating observable events, given small samples of factual observations. We manipulated prior probabilities of the states, and we rendered the priors calculable or incalculable, respectively. The analysis of choice behavior revealed that the tendency to consider prior probabilities when making decisions about hidden states was stronger when prior probabilities were calculable, at least in some of our participants. Surprise-related P3b amplitudes were observed in both the calculable and the incalculable prior probability condition. In contrast, calculability of prior probabilities modulated anteriorly distributed ERP amplitudes: when prior probabilities were calculable, surprising events elicited enhanced P3a amplitudes. However, when prior probabilities were incalculable, surprise was associated with enhanced N2 amplitudes. Furthermore, interindividual variability in reliance on prior probabilities was associated with attenuated P3b surprise responses under calculable in comparison to incalculable prior probabilities. Our results suggest two distinct neural systems for probabilistic learning that are recruited depending on contextual cues such as the precision of probabilistic information. Individuals with stronger tendencies to rely on calculable prior probabilities seem to have better adapted expectations at their disposal, as indicated by an attenuation of their P3b surprise responses when prior probabilities are calculable.


Asunto(s)
Anticipación Psicológica/fisiología , Corteza Cerebral/fisiología , Conducta de Elección/fisiología , Potenciales Evocados/fisiología , Aprendizaje por Probabilidad , Adulto , Femenino , Humanos , Masculino , Adulto Joven
13.
BMC Med Inform Decis Mak ; 16: 31, 2016 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-26957320

RESUMEN

BACKGROUND: Diagnosis of neuromuscular diseases in primary care is often challenging. Rare diseases such as Pompe disease are easily overlooked by the general practitioner. We therefore aimed to develop a diagnostic support tool using patient-oriented questions and combined data mining algorithms recognizing answer patterns in individuals with selected neuromuscular diseases. A multicenter prospective study for the proof of concept was conducted thereafter. METHODS: First, 16 interviews with patients were conducted focusing on their pre-diagnostic observations and experiences. From these interviews, we developed a questionnaire with 46 items. Then, patients with diagnosed neuromuscular diseases as well as patients without such a disease answered the questionnaire to establish a database for data mining. For proof of concept, initially only six diagnoses were chosen (myotonic dystrophy and myotonia (MdMy), Pompe disease (MP), amyotrophic lateral sclerosis (ALS), polyneuropathy (PNP), spinal muscular atrophy (SMA), other neuromuscular diseases, and no neuromuscular disease (NND). A prospective study was performed to validate the automated malleable system, which included six different classification methods combined in a fusion algorithm proposing a final diagnosis. Finally, new diagnoses were incorporated into the system. RESULTS: In total, questionnaires from 210 individuals were used to train the system. 89.5 % correct diagnoses were achieved during cross-validation. The sensitivity of the system was 93-97 % for individuals with MP, with MdMy and without neuromuscular diseases, but only 69 % in SMA and 81 % in ALS patients. In the prospective trial, 57/64 (89 %) diagnoses were predicted correctly by the computerized system. All questions, or rather all answers, increased the diagnostic accuracy of the system, with the best results reached by the fusion of different classifier methods. Receiver operating curve (ROC) and p-value analyses confirmed the results. CONCLUSION: A questionnaire-based diagnostic support tool using data mining methods exhibited good results in predicting selected neuromuscular diseases. Due to the variety of neuromuscular diseases, additional studies are required to measure beneficial effects in the clinical setting.


Asunto(s)
Minería de Datos/métodos , Sistemas de Apoyo a Decisiones Clínicas , Enfermedades Neuromusculares/diagnóstico , Reconocimiento de Normas Patrones Automatizadas/métodos , Humanos , Proyectos Piloto , Estudios Prospectivos , Encuestas y Cuestionarios
14.
J Dtsch Dermatol Ges ; 14(3): 321-38, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26972210

RESUMEN

The present guidelines on dermatomyositis (DM) represent an excerpt from the interdisciplinary S2k guidelines on myositis syndromes of the German Society of Neurology (available at www.awmf.org). The cardinal symptom of myositis in DM is symmetrical proximal muscle weakness. Elevated creatine kinase, CRP or ESR as well as electromyography and muscle biopsy also provide important diagnostic clues. Pharyngeal, respiratory, cardiac, and neck muscles may also be affected. Given that approximately 30% of patients also develop interstitial lung disease, pulmonary function tests should be part of the diagnostic workup. Although the cutaneous manifestations in DM are variable, taken together, they represent a characteristic and crucial diagnostic criterion for DM. Approximately 5-20% of individuals exhibit typical skin lesions without any clinically manifest muscle involvement (amyopathic DM). About 30% of adult DM cases are associated with a malignancy. This fact, however, should not delay the treatment of severe myositis. Corticosteroids are the therapy of choice in myositis (1-2 mg/kg). Additional immunosuppressive therapy is frequently required (azathioprine, for children methotrexate). In case of insufficient therapeutic response, the use of intravenous immunoglobulins is justified. The benefit of rituximab has not been conclusively ascertained yet. Acute therapeutic management is usually followed by low-dose maintenance therapy for one to three years. Skin lesions do not always respond sufficiently to myositis therapy. Effective treatment for such cases consists of topical corticosteroids and sometimes also calcineurin inhibitors. Systemic therapies shown to be effective include antimalarial agents (also in combination), methotrexate, and corticosteroids. Intravenous immunoglobulins or rituximab may also be helpful. UV protection is an important prophylactic measure.


Asunto(s)
Dermatología/normas , Dermatomiositis/diagnóstico , Dermatomiositis/terapia , Técnicas de Diagnóstico Neurológico , Neurología/normas , Guías de Práctica Clínica como Asunto , Corticoesteroides/uso terapéutico , Alemania , Inmunosupresores/uso terapéutico
15.
Hum Brain Mapp ; 36(8): 2878-89, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25913637

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder characterized by muscular atrophy, spasticity, and bulbar signs caused by loss of upper and lower motor neurons. Evidence suggests that ALS additionally affects other brain areas including premotor cortex and supplementary motor area. Here, we studied movement execution and inhibition in ALS patients using a stop-signal paradigm and functional magnetic resonance imaging. Seventeen ALS patients and 17 age-matched healthy controls performed a stop-signal task that required responding with a button press to a right- or left-pointing black arrow (go-stimuli). In stop-trials, a red arrow (stop-stimulus) was presented shortly after the black arrow indicating to withhold the prepared movement. Patients had by trend higher reaction times in go-trials but did not differ significantly in their inhibition performance. Patients showed stronger inhibition-related activity in inferior, superior, and middle frontal gyri as well as in putamen and pallidum. Error-related activity, conversely, was found to be stronger in healthy controls, particularly in the insula bilaterally. Patients also showed increased activity in the motor cortex during button presses. The results provide evidence for altered prefrontal and subcortical networks underlying motor execution, motor inhibition, and error monitoring in ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Encéfalo/fisiopatología , Inhibición Psicológica , Desempeño Psicomotor/fisiología , Adulto , Anciano , Mapeo Encefálico , Función Ejecutiva/fisiología , Femenino , Fuerza de la Mano , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiopatología , Pruebas Neuropsicológicas
16.
Muscle Nerve ; 51(5): 669-75, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25155020

RESUMEN

INTRODUCTION: In this study we sought to determine the cross-sectional area (CSA) of peripheral nerves in patients with distinct subtypes of amyotrophic lateral sclerosis (ALS). METHODS: Ulnar and median nerve ultrasound was performed in 78 ALS patients [classic, n = 21; upper motor neuron dominant (UMND), n = 14; lower motor neuron dominant (LMND), n = 20; bulbar, n = 15; primary lateral sclerosis (PLS), n = 8] and 18 matched healthy controls. RESULTS: Compared with controls, ALS patients had significant, distally pronounced reductions of ulnar CSA (forearm/wrist level) across all disease groups, except for PLS. Median nerve CSA (forearm/wrist level) did not differ between controls and ALS. CONCLUSION: Ulnar nerve ultrasound in ALS subgroups revealed significant differences in distal CSA values, which suggests it has value as a marker of LMN involvement. Its potential was particularly evident in the UMND and PLS groups, which can be hard to separate clinically, yet their accurate separation has major prognostic implications.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Nervios Periféricos/diagnóstico por imagen , Fenotipo , Anciano , Esclerosis Amiotrófica Lateral/clasificación , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Nervio Mediano/diagnóstico por imagen , Persona de Mediana Edad , Músculo Esquelético/inervación , Nervio Cubital/diagnóstico por imagen , Ultrasonografía
17.
J Neural Transm (Vienna) ; 122(9): 1279-82, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25645865

RESUMEN

Injection site pain (ISP) reduces compliance of botulinum toxin (BT) therapy considerably. We wanted to study whether nitrous oxide/oxygen (NOO, Livopan(®), Linde Gas Therapeutics, Unterschleißheim, Germany) can reduce ISP in patients receiving intracutaneous BT injections for axillary or palmar hyperhidrosis (HH). The study followed an open-label design comparing intraindividually ISP in both axillae and/or both palms when NOO was applied or not during BT injections. BT efficacy was measured by the Hyperhidrosis Disease Severity Scale (HDSS) and by a 4-point Self-Assessment Scale. ISP was documented by a Visual Analogue Scale (VAS) and the Verbal Scale of Pain Intensity (VSPI), adverse effects by a Structuralised Interview (SI). Altogether 13 patients (age 34.1 ± 12.4 years, 9 females, 4 males) were studied. 11 BT treatments were for biaxillary and 3 for bipalmar HH. BT reduced biaxillary HH from HDSS 3.7 ± 0.5 to 1.0 ± 0 and bipalmar HH from 3.6 ± 0.6 to 1.0 ± 0. All patients reported ISP reduction by NOO. In axillary HH, NOO reduced ISP from 55.7 ± 12.7 to 12.8 ± 7.5 on the VAS (p < 0.05) and from 4.1 ± 0.3 to 0.7 ± 0.5 on the VSPI (p < 0.05), in bipalmar HH from 60.0 ± 10.0 to 13.3 ± 5.8 on the VAS (p < 0.05) and from 5.0 ± 0 to 1.3 ± 0.5 on the VSPI (p < 0.05). Adverse effects were not identified. NOO is a potent, non-sedative, quickly reversible and safe inhalative analgesic which reduces ISP considerably in patients receiving BT therapy for axillary and palmar HH thus substantially improving compliance of BT therapy.


Asunto(s)
Analgésicos/uso terapéutico , Toxinas Botulínicas/administración & dosificación , Fármacos Dermatológicos/administración & dosificación , Hiperhidrosis/tratamiento farmacológico , Óxido Nitroso/uso terapéutico , Oxígeno/uso terapéutico , Adulto , Axila , Toxinas Botulínicas/efectos adversos , Fármacos Dermatológicos/efectos adversos , Femenino , Mano , Humanos , Hiperhidrosis/fisiopatología , Inyecciones Intradérmicas/efectos adversos , Masculino , Dolor/tratamiento farmacológico , Dolor/fisiopatología , Dimensión del Dolor , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
18.
J Neural Transm (Vienna) ; 122(3): 427-31, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25059456

RESUMEN

Botulinum toxin (BT) therapy is the treatment of choice for blepharospasm (BPS). Currently available BT type A drugs include Botox(®), Dysport(®) and Xeomin(®). Until now, there are few long-term studies on BT therapy for BPS. This is the first long-term study comparing all three major BT drugs. We collected treatment, efficacy and adverse effect data on BPS patients treated with either Botox(®), Dysport(®) or Xeomin(®) for at least eight consecutive treatments. Two hundred and eighty-eight patients (208 females, 80 males, age 62 ± 12 years) were included in this study. The treatment time was 11.2 ± 4.1 years covering 10,701 injection series. Doses were 47 ± 10 MU for Botox(®), 120 ± 35 MU for Dysport(®) and 62 ± 11 MU for Xeomin(®) (Botox(®) dose vs Xeomin(®) dose: p < 0.001, unpaired t test). 85 % of all patients had stable doses. The onset of the therapeutic effect was after 6.1 ± 3.3 days and its duration lasted 10.2 ± 3.5 weeks. The Global Clinical Improvement (GCI, 0 = no, 1 = slight, 2 = moderate, 3 = marked improvement in severity and function) as estimated by the patient was 2.5 ± 0.6. It was stable in 90% of the patients. Adverse effect frequency was 3.0% (ptosis 2.3%, dry eye 0.5%, diplopia 0.2%). None of these findings was significantly different between Botox(®), Dysport(®) and Xeomin(®). Our study, one of the largest studies on BT therapy of BPS and the study with the longest follow-up, confirms that BT therapy produces robust clinical improvement which is stable throughout the treatment time. Therapeutic effects start after 6.1 days and last for about 10 weeks before they start to vanish. With this, they are approximately 2 weeks shorter than the recommended inter-injection interval. Adverse effects were rare, mild and always transient. BT therapy is a safe and effective treatment for BSP. Shorter inter-injection intervals may improve therapeutic results.


Asunto(s)
Inhibidores de la Liberación de Acetilcolina/uso terapéutico , Blefaroespasmo/tratamiento farmacológico , Toxinas Botulínicas Tipo A/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
19.
BMC Neurol ; 15: 84, 2015 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-25982050

RESUMEN

BACKGROUND: Due to lack of any curative therapy for ALS, symptomatic treatment and maintenance of quality of life (QoL) is very important. We aimed to characterize the affected domains of QoL in ALS patients and to identify factors which are associated with reduced QoL and increased depression. METHODS: 159 ALS patients answered standardized questionnaires (Beck Depression Inventory-II, SF-36 Health Survey questionnaire, revised ALS functional rating scale). Multiple regression analysis was used to identify correlations between clinical features of ALS patients and depression/QoL scores. In addition, QoL data from ALS patients were compared to age-matched reference values representing the German normal population. RESULTS: QoL of ALS patients was reduced in nearly all SF-36-categories. Progression of physical impairment was positively correlated with depression but reduced QoL scores only in items directly related to physical function. However, QoL was considerably influenced by depression, independently from physical impairment. Regarding distinct patient characteristics one of the most interesting findings was that increasing age was correlated with significantly worse QoL results regarding social functioning. CONCLUSIONS: Depressive symptoms had a strong influence on QoL, hence their detection and treatment is of particular importance. Different domains of QoL are differently affected in subgroups of ALS patients. Being aware of these differences can be valuable for both ALS professional and family caregivers and physicians.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Esclerosis Amiotrófica Lateral/psicología , Depresión/psicología , Calidad de Vida/psicología , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
J Neuroinflammation ; 11: 19, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24479415

RESUMEN

We report the first case of combined retinal and CNS varicella zoster-associated vasculitis in a 49-year-old patient with multiple sclerosis who had been treated with natalizumab. He presented with a progressive bilateral visual loss. The diagnosis of a vasculitis was based on the fundoscopic examination and MRI findings. We confirmed the varicella zoster virus (VZV) infection of the CNS by PCR and increased intrathecal antibody indices in the cerebrospinal fluid. The patient was stabilized with antiviral treatment, methylprednisolone, plasmapheresis and cycophosphamide. Natalizumab was discontinued. This case illustrates the neuroimmunological and neuroinfectiological consequences of treatments with biologicals that influence the immune system.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Herpes Zóster/complicaciones , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/tratamiento farmacológico , Vasculitis del Sistema Nervioso Central/complicaciones , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Natalizumab
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