234 research outputs found
Pathophysiology and Treatment of Functional Paralysis: Insight from Transcranial Magnetic Stimulation
Functional paralysis (FP) or limb weakness is a common presentation of functional movement disorders (FMD), accounting for 18.1% of the clinical manifestations of FMD. The pathophysiology of FP is not known, but imaging studies have identified changes in structural and functional connectivity in multiple brain networks. It has been proposed that noninvasive brain stimulation techniques may be used to understand the pathophysiology of FP and may represent a possible therapeutic option. In this paper, we reviewed transcranial magnetic stimulation studies on functional paralysis, focusing on their pathophysiological and therapeutical implications. Overall, there is general agreement on the integrity of corticospinal pathways in FP, while conflicting results have been found about the net excitability of the primary motor cortex and its excitatory/inhibitory circuitry in resting conditions. The possible involvement of spinal cord circuits remains an under-investigated area. Repetitive transcranial magnetic stimulation appears to have a potential role as a safe and viable option for the treatment of functional paralysis, but more studies are needed to investigate optimal stimulation parameters and clarify its role in the context of other therapeutical options
Uno studio sullâinnovazione nellâindustria chimica
In our analysis, we have remembered the general result reached by studies on innovation of late, according to which innovation in manufacturing industry is a complex phenomenon and does not lend itself to be described and explained through simplistic analytical models. We have then taken clue from a variegated description of the firmsâ innovative behaviour, based on several indicators of their innovativeness. Our results confirm the idea that remarkable differences exist between the two sub-sectors into which chemical industry is broken down: pharmaceutical and basic chemicals. As for policy implications, the close correlation between patents and basic-research expenditure suggests that the Italian Fund for basic research (FIRB) might be useful in order to promote innovation in chemical industry.Industria chimica; Innovazione; Ricerca
Tools for the evaluation of low back pain impairment: a critical review.
Low back pain is a common musculoskeletal disorder which affects the lumbar segment of the spine. It can be either acute, subacute or chronic in its clinical presentation. Typically, the symptoms of low back pain do show significant improvement within two to three months from its onset. In a significant number of individuals, low back pain tends to be recurrent in nature with a waxing and waning quality to it. In a small proportion of sufferers this condition can become chronic. Population studies show that back pain affects most adults at some stage in their life and accounts for more sick leave and disability than any other single medical condition. This book presents new leading-edge research on this topic. The Chapt VI âTools for the Evaluation of Low Back Pain Impairment: A Critical Reviewâ put on light different LBP questionnaires and the different aspects of LBP they can report. In particular here is examined the role of Visual Analogic Scale (VAS) compared with the Owestry Questionnaire and the Roland-Morris Disability Questionnaire. Many works and researchers in scientific literature considered these test and their different data are here analysed to better point our attention in the tools to be considered to evaluate LBP
Rethinking the neurophysiological concept of cortical myoclonus
Cortical myoclonus is thought to result from abnormal electrical discharges arising in the sensorimotor cortex. Given the ease of recording of cortical discharges, electrophysiological features of cortical myoclonus have been better characterized than those of subcortical forms, and electrophysiological criteria for cortical myoclonus have been proposed. These include the presence of giant somatosensory evoked potentials, enhanced long-latency reflexes, electroencephalographic discharges time-locked to individual myoclonic jerks and significant cortico-muscular connectivity. Other features that are assumed to support the cortical origin of myoclonus are short-duration electromyographic bursts, the presence of both positive and negative myoclonus and cranial-caudal progression of the jerks. While these criteria are widely used in clinical practice and research settings, their application can be difficult in practice and, as a result, they are fulfilled only by a minority of patients. In this review we reappraise the evidence that led to the definition of the electrophysiological criteria of cortical myoclonus, highlighting possible methodological incongruencies and misconceptions. We believe that, at present, the diagnostic accuracy of cortical myoclonus can be increased only by combining observations from multiple tests, according to their pathophysiological rationale; nevertheless, larger studies are needed to standardise the methods, to resolve methodological issues, to establish the diagnostic criteria sensitivity and specificity and to develop further methods that might be useful to clarify the pathophysiology of myoclonus
Development of a new Front End electronics in Silicon and Silicon-Germanium technology for the Resistive Plate Chamber detector for high rate experiments
The upgrade of the Resistive Plate Chamber (RPC) detector, in order to
increase the detector rate capability and to be able to work efficiently in
high rate environment, consists in the reduction of the operating voltage along
with the detection of signals which are few hundred {\mu}V small. The approach
chosen by this project to achieve this objective is to develop a new kind of
Front End electronics which, thanks to a mixed technology in Silicon and
Silicon-Germanium, enhance the detector performances increasing its rate
capability. The Front End developed is composed by a preamplifier in Silicon
BJT technology with a very low inner noise (1000 rms) and an
amplification factor of 0.3-0.4 mV/fC and a new kind of discriminator in SiGe
HJT technology which allows a minimum threshold of the order of 0.5 mV. The
performances of this kind of Front End will be shown. The results are obtained
by using the CERN H8 beamline with a full-size RPC chamber of 1 mm gas gap and
1.2 mm thickness of electrodes equipped with this kind of Front End
electronics.Comment: 14th Workshop on Resistive Plate Chambers and Related Detectors 19-23
February, 2018 Puerto Vallarta, Jalisco state, Mexic
Rethinking the neurophysiological concept of cortical myoclonus
Cortical myoclonus is thought to result from abnormal electrical discharges arising in the sensorimotor cortex. Given the ease of recording of cortical discharges, electrophysiological features of cortical myoclonus have been better characterized than those of subcortical forms, and electrophysiological criteria for cortical myoclonus have been proposed. These include the presence of giant somatosensory evoked potentials, enhanced long-latency reflexes, electroencephalographic discharges time-locked to individual myoclonic jerks and significant cortico-muscular connectivity. Other features that are assumed to support the cortical origin of myoclonus are short-duration electromyographic bursts, the presence of both positive and negative myoclonus and cranial-caudal progression of the jerks. While these criteria are widely used in clinical practice and research settings, their application can be difficult in practice and, as a result, they are fulfilled only by a minority of patients. In this review we reappraise the evidence that led to the definition of the electrophysiological criteria of cortical myoclonus, highlighting possible methodological incongruencies and misconceptions. We believe that, at present, the diagnostic accuracy of cortical myoclonus can be increased only by combining observations from multiple tests, according to their pathophysiological rationale; nevertheless, larger studies are needed to standardise the methods, to resolve methodological issues, to establish the diagnostic criteria sensitivity and specificity and to develop further methods that might be useful to clarify the pathophysiology of myoclonus
Changes in cerebellar output abnormally modulates cortical myoclonus sensorimotor hyperexcitability
Cortical myoclonus is produced by abnormal neuronal discharges within the sensorimotor cortex, as demonstrated by electrophysiology. Our hypothesis is that the loss of cerebellar inhibitory control over the motor cortex, via cerebello-thalamo-cortical connections, could induce the increased sensorimotor cortical excitability that eventually causes cortical myoclonus. To explore this hypothesis, in the present study we applied anodal transcranial direct current stimulation over the cerebellum of patients affected by cortical myoclonus and healthy controls and assessed its effect on sensorimotor cortex excitability. We expected that anodal cerebellar transcranial direct current stimulation would increase the inhibitory cerebellar drive to the motor cortex and therefore reduce the sensorimotor cortex hyperexcitability observed in cortical myoclonus. Ten patients affected by cortical myoclonus of various aetiology and 10 aged-matched healthy controls were included in the study. All participants underwent somatosensory evoked potentials, long-latency reflexes, and short-interval intracortical inhibition recording at baseline and immediately after 20 min session of cerebellar anodal transcranial direct current stimulation. In patients, myoclonus was recorded by the means of surface electromyography before and after the cerebellar stimulation. Anodal cerebellar transcranial direct current stimulation did not change the above variables in healthy controls, while it significantly increased the amplitude of somatosensory evoked potential cortical components, long-latency reflexes and decreased short-interval intracortical inhibition in patients; alongside, a trend towards worsening of the myoclonus after the cerebellar stimulation was observed. Interestingly, when dividing patients in those with and without giant somatosensory evoked potentials, the increment of the somatosensory evoked potential cortical components was observed mainly in those with giant potentials. Our data showed that anodal cerebellar transcranial direct current stimulation facilitates, and does not inhibit, sensorimotor cortex excitability in cortical myoclonus syndromes. This paradoxical response might be due to an abnormal homeostatic plasticity within the sensorimotor cortex, driven by dysfunctional cerebello-thalamo-cortical input to the motor cortex. We suggest that the cerebellum is implicated in the pathophysiology of cortical myoclonus and that these results could open the way to new forms of treatment or treatment targets
Uno studio sullâinnovazione nellâindustria chimica (Italian chemical firms' innovative behaviour)
WP 03/2004; In our analysis, we have remembered the general result reached by studies on innovation of late, according to which innovation in manufacturing industry is a complex phenomenon and does not lend itself to be described and explained through simplistic analytical models. We have then taken clue from a variegated description of the firmsâ innovative behaviour, based on several indicators of their innovativeness. Our results confirm the idea that remarkable differences exist between the two sub-sectors into which chemical industry is broken down: pharmaceutical and basic chemicals. As for policy implications, the close correlation between patents and basic-research expenditure suggests that the Italian Fund for basic research (FIRB) might be useful in order to promote innovation in chemical industry
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