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1.
Phys Rev Lett ; 126(11): 117205, 2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33798341

RESUMEN

We report experimental coupling of chiral magnetism and superconductivity in [IrFeCoPt]/Nb heterostructures. The stray field of skyrmions with radius ≈50 nm is sufficient to nucleate antivortices in a 25 nm Nb film, with unique signatures in the magnetization, critical current, and flux dynamics, corroborated via simulations. We also detect a thermally tunable Rashba-Edelstein exchange coupling in the isolated skyrmion phase. This realization of a strongly interacting skyrmion-(anti)vortex system opens a path toward controllable topological hybrid materials, unattainable to date.

2.
Eur J Neurol ; 27(2): 392-398, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31536677

RESUMEN

BACKGROUND AND PURPOSE: Rehabilitation plays a central role in stroke recovery. Besides conventional therapy, technological treatments have become available. The effectiveness and appropriateness of technological rehabilitation are not yet well defined; hence, research focused on different variables impacting recovery is needed. Results from the literature identified cognitive reserve (CR) as a variable impacting on the cognitive outcome. In this paper, the aim was to evaluate whether CR influences the motor outcome in patients after stroke treated with conventional or robotic therapy and whether it may influence one treatment rather than another. METHODS: Seventy-five stroke patients were enrolled in five Italian neurological rehabilitation centres. Patients were assigned either to a robotic group, rehabilitation by means of robotic devices, or to a conventional group, where a traditional approach was used. Patients were evaluated at baseline and after rehabilitation treatment of 6 weeks through the Action Research Arm Test (ARAT), the Motricity Index (MI) and the Barthel Index (BI). CR was assessed at baseline using the Cognitive Reserve Index (CRI) questionnaire. RESULTS: Considering all patients, a weak correlation was found between the CRI related to leisure time and MI evolution (r = 0.276; P = 0.02). Amongst the patients who performed a robotic rehabilitation, a moderate correlation emerged between the CRI related to working activities and MI evolution (r = 0.422; P = 0.02). CONCLUSIONS: Our results suggest that CR may influence the motor outcome. For each patient, CR and its subcategories should be considered in the choice between conventional and robotic treatment.


Asunto(s)
Reserva Cognitiva , Procedimientos Quirúrgicos Robotizados , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Recuperación de la Función , Resultado del Tratamiento , Extremidad Superior
3.
J Biol Regul Homeost Agents ; 34(5 Suppl. 3): 1-9. Technology in Medicine, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33386031

RESUMEN

Focal muscular vibration (FMV) is a non-invasive technique that showed positive effects on spasticity of the upper limb in stroke subjects but different protocols have been proposed so the studies are not comparable and, to date, it is not clear which muscles should be treated, agonist, or antagonist muscles to obtain the better result on spasticity. The objective of this study is to evaluate the effects on spasticity of FMV on the upper limb flexor spastic muscles compared to the effects of FMV on the upper limb extensor muscles in subacute stroke patients. We treated 28 subacute stroke patients (mean age 64.28±13.79) randomized into two groups: Group A and Group B. Group A was treated by applying FMV to the flexor muscles of the upper limb, while Group B was treated by applying FMV to the extensor muscles of the upper limb. The effects on spasticity were assessed by Modified Ashworth Scale (primary outcome) and the upper limb motor function by instrumental robotic outcomes; moreover, muscle strength and pain were evaluated using Motricity Index and Numerical Rating Scale, respectively (secondary outcomes). Patients were subjected to FMV for three consecutive days and were evaluated three times: before treatment (T0), after a week (T1) and after a month (T2) from the end of treatment. Within group, analysis showed statistically significant changes over time of the MAS at the three joints (shoulder, elbow and wrist) in both groups, but post-hoc analysis showed that, only in Group A, MAS was significantly lower at T2, when compared with T0 at the shoulder and elbow. NRS, significantly changed over time only in the Group B. Motricity Index, did not change over time neither in the Group A, nor in the Group B. No statistically significant differences were detected in the between group analysis. Regarding the instrumental robotic outcomes, we detected a statistically significant reduction of the time required to complete the task (Duration) in both group a T2. In conclusion, this study highlighted how the same treatment protocol can determine an improvement in muscle tone and in the Duration to perform a task, regardless of the muscles treated, while the pain improves if we treat the agonist muscles.


Asunto(s)
Espasticidad Muscular , Accidente Cerebrovascular , Anciano , Humanos , Persona de Mediana Edad , Espasticidad Muscular/etiología , Espasticidad Muscular/terapia , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/terapia , Resultado del Tratamiento , Extremidad Superior , Vibración/uso terapéutico
4.
J Biol Regul Homeost Agents ; 34(5 Suppl. 3): 201-208. Technology in Medicine, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33386050

RESUMEN

Upper limb recovery is a complex process and a strong challenge in the rehabilitation of patients after stroke. Several studies have been conducted to compare the efficacy of conventional and robotic rehabilitation to restore the upper limb motor impairment following a stroke. However, the evolution of the upper limb motor ability during an intervention, as well as the time point when the patient stops improving (the so call plateau), are rarely measured, and never compared between the two approaches. These latter aspects are very important considering the need for an optimization of the economic resources. In this study, the time course of the upper limb motor recovery of 24 subacute stroke patients undergoing a 30-session robotic or conventional treatment was analyzed through the upper extremity portion of the Fugl-Meyer Assessment scale (FMA-UE). The FMA-UE was administered before the treatment, and after 10, 20, and 30 rehabilitation sessions. Statistical analysis showed that, according to the FMA-UE, the time course in the two groups was similar: patients did not change between the baseline and the 10-session assessment, while they improved between 10 and 20 sessions, and between 20 and 30 sessions, with most of the gain observed between 10 and 20 sessions. This result suggests that 30-session robotic or conventional rehabilitation programs induce a similar curve trend in the upper limb motor recovery of patients with subacute stroke, with an important increase in the middle of the program and without reaching a clear plateau in the analyzed time interval.


Asunto(s)
Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Recuperación de la Función , Robótica , Resultado del Tratamiento , Extremidad Superior
5.
Ann Ig ; 29(4): 256-263, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28569335

RESUMEN

BACKGROUND: In Italy, the general practitioner (GP) is the operations manager of the campaigns regarding influenza immunization. He/she identifies people eligible for vaccination among the clients, invites them actively and administers the vaccine. The GPs are directly in contact with the target population that should be vaccinated and their opinion about the flu vaccine may ultimately influence the decision of the patient to accept or not the vaccination. This study aims to assess levels of immunization for influenza vaccination among GPs and factors influencing their adherence to the vaccinations recommended for GPs in the province of Taranto (Apulia region, Southern Italy). METHODS: We conducted a cross-sectional study among 471 general practitioners working in the province of Taranto during the February-March period of 2016. We emailed all GPs a self-administered web-based standardized questionnaire. The questionnaire analyzed the self-reported flu vaccination coverage, knowledge, perception and positions of the GPs with regard to the forecasted vaccinations of the in-risk categories among their patients. RESULTS: A total of 229 (48.6%) GPs participated in the survey. In the 2015/2016 influenza season, the vaccination coverage among the interviewed GPs was 76.4% (n = 175). A patient number ≥ 900 increased the likelihood to have been vaccinated in the 2015/2016 season (OR = 3.3; P < 0.01). Overall only 79.9% prefers to use the adjuvated vaccines on patients > 64 and the 58% of GPs who chose not to get vaccinated considers influenza as a non-risk pathology for a healthy subject. CONCLUSIONS: The coverage achieved among the Taranto's ASL GPs during the 2015/16 season reaches the minimum threshold set by the Minister, but they could implement their knowledge and their participation in relation to the anti-influenza vaccine in order to discard all the wrong or clearly unfounded common beliefs. The best strategy in order to optimize the governance system seems to be the empowerment of primary care physicians, to be fulfilled through actions shared with the Public Healthcare Services based on training, communication and projects supporting vaccine coverage.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/prevención & control , Vacunación/estadística & datos numéricos , Adulto , Anciano , Actitud del Personal de Salud , Estudios Transversales , Femenino , Médicos Generales/estadística & datos numéricos , Adhesión a Directriz , Encuestas de Atención de la Salud , Humanos , Italia , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina/estadística & datos numéricos , Estaciones del Año
6.
Acta Neurol Scand ; 133(5): 346-54, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26234280

RESUMEN

OBJECTIVE: Multiple sclerosis (MS), Parkinson's disease (PD) and stroke (ST) subjects show balance impairments due to damage of the balance control system. The objective of the study was to assess the impact of MS, PD and ST on upright posture in eyes open condition and when visual and/or proprioceptive inputs are altered. MATERIALS AND METHODS: A total of 188 subjects with MS (n = 80), PD (n = 58) and ST (n = 50), mean age (SD), 57.9 (14.6) years, and 32 healthy subjects (HS) aged 53.7 (15.7) years were assessed by a stabilometric platform in a cross-sectional study. RESULTS: Compared to HS, MS showed large deviations from normal performances with respect to magnitude (P < 0.001) and regularity (P < 0.05) of body sway irrespective of the altered sensory information. Similarly to MS, PD showed large and abnormal levels of body sway (P < 0.001) and postural tremor (P < 0.05), while ST was the least impaired except for an asymmetrical distribution of body weight between legs (P < 0.001). Finally, the MS group compared to PD and ST showed the largest body instability after eye closure (P < 0.05) and when visual and proprioceptive inputs were removed (P < 0.05). PD showed instability mainly after the alteration of proprioceptive inputs (P < 0.05), while ST showed the smallest increase of body instability when sensory inputs were reduced. DISCUSSION: Objective assessment revealed pathology-specific balance disorders and showed the differential impact of MS, PD and ST on the ability to use sensory information for balance control.


Asunto(s)
Esclerosis Múltiple/fisiopatología , Enfermedad de Parkinson/fisiopatología , Equilibrio Postural , Accidente Cerebrovascular/fisiopatología , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Enfermedad de Parkinson/diagnóstico , Postura , Accidente Cerebrovascular/diagnóstico
7.
Artículo en Inglés | MEDLINE | ID: mdl-39269794

RESUMEN

Bilateral robotic rehabilitation has proven helpful in the recovery of upper limb motor function in patients with stroke, but its effects on the cortical reorganization mechanisms underlying recovery are still unclear. This pilot Randomized Controlled Trial (RCT) aimed to evaluate the effects on the interhemispheric balance of unilateral or bilateral robotic treatments in patients with subacute stroke, using Quantitative Electroencephalography (qEEG). 19 patients with ischemic stroke underwent a 30-session upper limb neurorehabilitation intervention using a bilateral upper limb exoskeleton. Each patient was randomly assigned to the bilateral (BG, n=10) or unilateral treatment group (UG, n=9). EEG evaluations were performed before (T0) and right after (T [Formula: see text] the first treatment session, after 30 treatment sessions (T1), and at 1-week follow-up (T2), in both eyes open and eyes closed conditions. From the acquired EEG data, the pairwise-derived Brain Symmetry Index (pdBSI) was computed. In addition, clinical evaluation was performed at T0 and T1 with validated clinical scales. After the treatment, a significant improvement in clinical and EEG evaluations was observed for both groups, but only the BG showed reduced pdBSI in delta and theta bands. In the cluster of sensorimotor channels, there was no significant difference between groups. The observed changes were not maintained at follow-up. No significant changes were observed in the pdBSI after a single rehabilitation session. Results suggest that balancing of interhemispheric symmetry comes along with a clinical improvement in the upper extremity and that the pdBSI can be used to investigate the mechanisms of neuronal plasticity involved in robotic rehabilitation after stroke.


Asunto(s)
Electroencefalografía , Dispositivo Exoesqueleto , Robótica , Rehabilitación de Accidente Cerebrovascular , Extremidad Superior , Humanos , Masculino , Rehabilitación de Accidente Cerebrovascular/métodos , Femenino , Proyectos Piloto , Persona de Mediana Edad , Extremidad Superior/fisiopatología , Anciano , Accidente Cerebrovascular/fisiopatología , Lateralidad Funcional , Adulto , Recuperación de la Función
8.
Neurol Sci ; 34(3): 373-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22434411

RESUMEN

Pain is a subjective condition that cannot be objectively measured; for this reason, self patient-perspective is crucial. Recently, several screening tools to discriminate between nociceptive and neuropathic pain have been developed. We aimed at assessing the consistence and discrepancy of two widely used screening tools, The Douleur Neuropathique 4 (DN4) and the 6-item questionnaire (ID-Pain), by comparing their ability in discriminating neuropathic from nociceptive pain. DN4 and ID-Pain were administered to 392 Italian patients attending 16 outpatient services for peripheral nerve diseases. Based on medical history, clinical findings and diagnostic tools, patients were divided into two groups (neuropathic and nociceptive). Globally, ID-Pain identified neuropathic pain in 60 % of patients (38 % probable, 22 % likely). Interestingly also DN4 diagnosed neuropathic pain in 60 % of cases. A discrepancy was observed in 16 % of cases. DN4 and ID-Pain resulted to be highly interrelated in the identification of neuropathic pain. Sensitivity of DN4 was 82 % and specificity was 81 %, while ID-Pain (considering both probable and likely groups) showed sensitivity 78 % and specificity 74 %. Reliable screening tools for neuropathic pain are well related between them; hence, they are available for researchers and clinicians who may choose the most appropriate for their activity. Since the gold standard for the diagnosis and treatment of neuropathic pain cannot do without a neurological evaluation, perhaps DN4, that includes physician objective measures, may help reducing the percentage of dubious cases. Conversely, when needing a more agile tool (not needing a physician) ID-Pain may be adopted.


Asunto(s)
Neuralgia/clasificación , Neuralgia/diagnóstico , Dimensión del Dolor/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto Joven
9.
IEEE Int Conf Rehabil Robot ; 2023: 1-6, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37941244

RESUMEN

Clinicians often deal with complex robotic platform and serious games in stroke patients rehabilitation contexts, and they face two main problems: 1) the interpretation of either the performance in game or measures of a robotic system from the motor recovery point of view, and 2) the duration and complexity of clinical scales administration that makes repetitive assessments during the therapy unpractical. In this paper, a Random Tree Forest based system was trained and tested to provide a prediction of different clinical outcomes (i.e. FMA, ARAT, and MI) along the whole therapy duration, having non-clinical measures only as inputs, acting as a simulated decision support system. The dataset includes 30 post-stroke patients, that underwent a 30-session robot-assisted rehabilitation treatment. Results have shown that the system is able to produce very accurate and reliable predictions about the motor recovery of the patient at the end of the therapy, already in the first phases of the rehabilitation (i40% of therapy execution), just using robotic platform measures. Such a tool would provide a great benefit in terms of rehabilitation objectives planning, as a decision support tool for highly personalized rehabilitation treatments.


Asunto(s)
Robótica , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Robótica/métodos , Recuperación de la Función , Rehabilitación de Accidente Cerebrovascular/métodos , Resultado del Tratamiento , Sobrevivientes , Extremidad Superior
10.
IEEE Int Conf Rehabil Robot ; 2022: 1-6, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-36176136

RESUMEN

Robotic-based rehabilitation administered by means of serious games certainly represents the frontier of rehabilitation treatments, offering a high degree of customization of therapy, to meet individual patients' needs and to tailor a proper rehabilitation therapy. Despite the rush on developing complex rehabilitation systems, they often do not provide clinicians with long-term information about the outcome of rehabilitation, thus, not supporting them in the initial set-up phase of the therapy. In this paper, a Random-Forest based system was trained and tested to provide a prediction at discharge of several clinical scales outcomes (i.e. FMA, ARAT, and MI), having clinical scale scores and measures from the robotic system at the enrollment as inputs. The dataset includes 25 post-stroke patients from different clinics, that underwent a variable number of days of rehabilitation with a robotic treatment. Results have shown that the system is able to predict the final outcome with an accuracy ranging from 60% to 73% on the selected scales. Also results provide information on which variables are more relevant for the prediction of outcome of therapy, in particular clinical scales scores such as FMA, ARAT, MI, NRS, PCS, and MCS and robotic automatically extracted measurements related to patient's work expenditure and time. This supports the idea of using such a system in a clinical environment in a decision support tool for clinicians.


Asunto(s)
Robótica , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Proyectos Piloto , Recuperación de la Función , Robótica/métodos , Rehabilitación de Accidente Cerebrovascular/métodos , Resultado del Tratamiento , Extremidad Superior
11.
Radiol Med ; 116(1): 1-14, 2011 Feb.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-20981503

RESUMEN

UNLABELLED: This paper analyses off-label prescribing of the iodinated organic and magnetic resonance (MR) contrast media used in diagnostic imaging and evaluates the liability profiles and medicolegal issues associated with such use. The term off-label generally indicates the use of known drugs for which new scientific evidence suggests use in a manner and in clinical scenarios not explicitly addressed by the drug data sheet and is outside the indications for which the medication was approved. In addition, the term also indicates the use of drugs with a different route of administration and dosage from those indicated in the information leaflet. Intravascular contrast media used in diagnostic imaging are drugs in the complete sense of the term, even though they have unique characteristics which in many ways distinguish them from other pharmacological agents. The off-label use of contrast media in diagnostic imaging is a little-investigated field and most commonly, but not exclusively, applies to gadolinium-based contrast media used in MR angiography as well as cardiac and paediatric applications. In particular, the off-label use of contrast media mostly concerns deviations from the recommended dose. As contrast media are to all effects pharmaceutical agents, their off-label use can be considered admissible within the limitations laid down by the Italian law in force (Article 3 of Law 94/98) and its interpretation, i.e. the following criteria must be present: the lack of a valid diagnostic alternative; written informed consent by the patient; the presence of scientific publications validated at the international level; assumption of responsibility by the radiologist. CONCLUSIONS: The use of contrast media in modern image-guided medicine is essential. In cases in which the information contained in the information leaflet is modified and updated in any way whatsoever (indications, dosage, at others), specifically if restrictions are introduced in accordance with the law in force, the pharmaceutical industry must provide formal and timely notification to radiologists. On their part as prescribers and users of contrast media, radiologists must remain up to date regarding any changes in indications, dosage and route of administration. Lastly, we propose that the radiology report includes not only the type but also the dose of contrast medium used.


Asunto(s)
Medios de Contraste/farmacología , Imagen por Resonancia Magnética , Uso Fuera de lo Indicado , Medios de Contraste/administración & dosificación , Medios de Contraste/efectos adversos , Humanos , Yodo , Italia , Uso Fuera de lo Indicado/economía , Uso Fuera de lo Indicado/ética , Uso Fuera de lo Indicado/legislación & jurisprudencia
12.
Int J Stroke ; 16(4): 396-405, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32640881

RESUMEN

BACKGROUND AND AIMS: Poststroke shoulder pain is a common complication. We aimed to investigate the prevalence of poststroke shoulder pain, with attention to the neuropathic component, and the relationship between poststroke shoulder pain and upper limb improvement in motor function, strength, disability, and quality of life after upper limb rehabilitation. METHODS: This is a secondary analysis of a multicenter randomized controlled trial to compare upper limb conventional or robotic rehabilitation on 224 patients enrolled in eight rehabilitation centers. We assessed poststroke shoulder pain (using the Numerical Rating Scale and the Douleur Neuropathique 4), and upper limb motor function, strength, disability, and quality of life at baseline (T0), after 30 rehabilitation sessions (T1), and three months after the end of rehabilitation (T2). RESULTS: A moderate/severe poststroke shoulder pain was reported by 28.9% of patients, while 19.6% of them showed a neuropathic component. At T0, the intensity of pain was higher in women and in patients with neglect syndrome, positively correlated with the time since stroke and disability and negatively correlated with motor function, strength, and the physical aspects of the quality of life.Moderate/severe pain and neuropathic component significantly reduced after both treatments and this reduction was maintained at T2. Finally, the intensity of pain at baseline was negatively correlated with the improvement of upper limb motor function. CONCLUSIONS: Poststroke shoulder pain negatively impact on motor performance, strength, disability, and physical aspects of the quality of life as well as on upper limb motor recovery; however, it can be reduced after a robotic or a conventional rehabilitation. Therefore, we suggest considering poststroke shoulder pain when planning the rehabilitation intervention.


Asunto(s)
Procedimientos Quirúrgicos Robotizados , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Femenino , Humanos , Calidad de Vida , Recuperación de la Función , Dolor de Hombro/epidemiología , Dolor de Hombro/etiología , Accidente Cerebrovascular/complicaciones , Resultado del Tratamiento , Extremidad Superior
13.
Phys Rev Lett ; 105(16): 167005, 2010 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21231000

RESUMEN

We probe the local quasiparticles density of states in micron-sized SmFeAsO(1-x)F(x) single crystals by means of scanning tunnelling spectroscopy. Spectral features resemble those of cuprates, particularly a dip-hump-like structure developed at energies larger than the gap that can be ascribed to the coupling of quasiparticles to a collective mode, quite likely a resonant spin mode. The energy of the collective mode revealed in our study decreases when the pairing strength increases. Our findings support spin-fluctuation-mediated pairing in pnictides.

14.
Neurol Sci ; 31(2): 175-8, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20016922

RESUMEN

Charcot-Marie-Tooth (CMT) disease is the most frequent inherited neuropathy, no therapies are available at the moment but clinical trials are ongoing. For that reason it is very important to know the natural history of the disease. We report the results of the natural history of clinical features and quality of life (QoL) in patients with CMT2. Twenty patients were enrolled. At recruitment and at follow-up (2 years), all patients underwent neurological evaluation, QoL and disability assessments. The study-end evaluation took place 20-28 months after the baseline evaluation. During the 2-year follow-up period, CMT2 patients showed a mild reduction of strength of distal muscles of upper limbs and proximal muscles of lower limbs, a worsening sensory function and a mild increase in walking disability. However, there was no relevant worsening of QoL, except for a mild deterioration of one mental health domain.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/fisiopatología , Enfermedad de Charcot-Marie-Tooth/psicología , Fuerza Muscular , Calidad de Vida , Caminata , Adolescente , Adulto , Evaluación de la Discapacidad , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Examen Neurológico , Adulto Joven
15.
Phys Rev Lett ; 103(22): 227001, 2009 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-20366120

RESUMEN

We have used scanning tunneling spectroscopy to investigate short-length electronic correlations in three-layer Bi2Sr2Ca2Cu3O(10+delta) (Bi-2223). We show that the superconducting gap and the energy Omega(dip), defined as the difference between the dip minimum and the gap, are both modulated in space following the lattice superstructure and are locally anticorrelated. Based on fits of our data to a microscopic strong-coupling model, we show that Omega(dip) is an accurate measure of the collective-mode energy in Bi-2223. We conclude that the collective mode responsible for the dip is a local excitation with a doping dependent energy and is most likely the (pi, pi) spin resonance.

16.
Cell Biol Toxicol ; 25(4): 321-30, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18523852

RESUMEN

Oxidative stress seems to play a major role in the pathogenesis of neurodegeneration. In Parkinson's disease (PD) patients, the dopaminergic neurons are subjected to oxidative stress resulting from reduced levels of antioxidant defenses such as glutathione and high amount of intracellular iron. Levodopa (LD) is widely used for the symptomatic treatment of PD, but its role in oxidative damage control is still unclear. The aim of this study was to analyze the presence of DNA damage in peripheral blood lymphocytes (PBL) of PD patients, during a washout and a controlled LD dosage and to evaluate the oxidative damage fluctuation after LD intake. The standard and the Fpg-modified version of Comet assay were applied in analyzing DNA damage in PBL from blood samples of nine PD patients and nine matched controls. Due to the limited number of patients we cannot reach definite conclusions even if our data confirm the accumulation of DNA lesions in PD patients; these lesions decrease after LD intake.


Asunto(s)
Antiparkinsonianos/farmacología , Células Sanguíneas/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Levodopa/farmacología , Enfermedad de Parkinson/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Antiparkinsonianos/uso terapéutico , Células Sanguíneas/metabolismo , Ensayo Cometa , Femenino , Humanos , Técnicas In Vitro , Levodopa/uso terapéutico , Masculino , Persona de Mediana Edad , Estrés Oxidativo
18.
Neuromuscul Disord ; 18(3): 199-203, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18242090

RESUMEN

The Italian CMT study group performed a multicentre, multidimensional, longitudinal 2-year follow-up study using validated measurements of neurological impairment, disability and quality of life. The aim of the study was to evaluate the natural history of clinical features, disability and QoL in patients with CMT1A. On clinical examination, CMT1A patients showed a significant reduction in muscle strength and sensory function during the 2-year follow-up period. However, there was no worsening of QoL or disability, nor was depression observed. The discrepancy between the evolution of clinical features and the evolution of QoL and disability may be due to the development of compensatory strategies that help patients cope with the slow progression of the disease. Our observations provide information which may be useful when designing clinical trials in CMT.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/fisiopatología , Enfermedad de Charcot-Marie-Tooth/psicología , Evaluación de la Discapacidad , Calidad de Vida , Encuestas y Cuestionarios/normas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados
19.
Clin Neurophysiol ; 119(7): 1600-6, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18450508

RESUMEN

OBJECTIVE: Motor conduction velocity may yield false-negative results in mild ulnar nerve entrapment at elbow (UNE). There is evidence that the clinical heterogeneity of UNE may be due to the different involvement of fascicles. We hypothesized that, if fibres to FDI are more damaged than fibres to ADM, a relative slowing of motor conduction velocity (CV) at the segment across the elbow recording from FDI (FDI-CV) versus CV at the same segment recording from ADM (ADM-CV) would occur. METHODS: We calculated the ratio between FDI-CV and ADM-CV (IN-RATIO) in 60 consecutive UNE patients, 40 norms, and 16 patients with lower cervical radiculopathy. The UNE sample consisted of (1) patients with neurophysiological evidence (UNE NF+), (2) patients without neurophysiological evidence (UNE NF-). We evaluated the possible usefulness of the IN-RATIO to increase sensitivity in diagnosing UNE. RESULTS: The IN-RATIO was lower in the UNE NF- than in norms (p<0.001) and cervicobrachialgia sample (p=0.02). We found that if the IN-RATIO is

Asunto(s)
Codo/inervación , Síndromes de Compresión Nerviosa/diagnóstico , Neuropatías Cubitales/diagnóstico , Adulto , Estudios de Casos y Controles , Codo/patología , Electrodiagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuronas Motoras/fisiología , Fibras Nerviosas/fisiología , Conducción Nerviosa , Probabilidad
20.
Clin Neurophysiol ; 118(6): 1410-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17466584

RESUMEN

OBJECTIVE: To evaluate the usefulness of a combination of electromyography (EMG) and ultrasound (US) assessments in diagnosing nerve trunk involvement. We hypothesised that in some cases, when the clinical or neurophysiological picture is unclear, the simultaneous study of the peripheral nervous system through both US and EMG may provide pathologic information not obtainable through EMG alone, and this may influence therapeutic decisions. METHODS: In 2005, we performed a prospective study in 77 consecutive patients with involvement of a single nerve trunk, using a combination of EMG and US in the same session. We divided the diagnostic contribution of US into four categories: diagnostic, confirming, inconclusive and misdiagnostic. RESULTS: In about a quarter of the patients, US provided results confirming the clinical neurophysiological diagnosis. In another quarter of the cases, US was very helpful in modifying diagnosis and therapy. In most of these cases, the contribution of US was important for the detection of tumors or cysts, thus showing the cause of nerve involvement. In half of the cases the US results were inconclusive, and in one case US was misdiagnostic. CONCLUSIONS: The combination of EMG and US performed in the same session (or in collaboration with an ultrasound examiner) may be useful for diagnosis and determination of appropriate therapy. SIGNIFICANCE: Diagnosis of mononeuropathies is improved through a combined functional and morphological evaluation of the nerve by using EMG and US.


Asunto(s)
Electromiografía/métodos , Síndromes de Compresión Nerviosa , Ultrasonografía/métodos , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Síndromes de Compresión Nerviosa/diagnóstico , Síndromes de Compresión Nerviosa/diagnóstico por imagen , Síndromes de Compresión Nerviosa/fisiopatología , Estudios Retrospectivos
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