Levodopa effect on electromyographic activation patterns of tibialis anterior muscle during walking in Parkinson's disease.

Previous studies have reported that patients with Parkinson's disease (PD) show, in the "off medication" state, a reduced activation of tibialis anterior (TA) in the late swing-early stance phase of the gait cycle. In PD patients the pathophysiological picture may cause differences among the stride cycles. Our aims were to evaluate how frequently TA activity is reduced in the late swing-early stance phase and if there is a relationship between the TA pattern and the clinical picture. Thirty PD patients were studied 2 h after Levodopa administration ("on-med") and 12 h after Levodopa wash-out ("off-med"). They were evaluated by the Unified Parkinson's Disease Rating Scale (UPDRS III) and surface electromyography of TA and gastrocnemius medialis (GM). The root mean square (RMS) of the TA activity in late swing-early stance phase (RMS-A) was normalized as a percent of the RMS of the TA activity in late stance-early swing (RMS-B). RMS-A was reduced in 30% of patients in the "off-med" condition. Within these patients, the percentage of stride cycles with reduced RMS-A, ranged between 28% and 83%. After Levodopa intake, no stride cycle showed reduced RMS-A. Patients with reduced RMS-A had a lower UPDRS III total score in the "on-med" rather than in the "off-med" condition (p=0.02). Our data confirm and extend previous observations indicating that, in "off-med" the function of TA is impaired in those patients clinically more responsive to Levodopa. TA activation is reduced in a relatively high percent of gait cycles in the "off-med" state. Since the variability of TA activation disappears after Levodopa administration, this phenomenon could be the expression of an abnormal dopaminergic drive.

Occurrence and characterization of Pain in immune-mediated neuropathies: a multicentre prospective study.

BACKGROUND: pain is a common symptom of peripheral neuropathies that may severely affect patients' Quality of Life. Pain questionnaires, based on verbal descriptors, are a useful way to investigate it. METHODS: we performed a multicentre study through validated measures to characterize pain in a sample of consecutive patients affected by immune-mediated neuropathies. RESULTS: ninety-three patients were enrolled in 16 Italian centres. Based on the numeric rating scale, almost half of the patients complained of moderate pain and one-third of the patients severe pain. Overall, up to 50% of our patients with immune-mediated neuropathies complained of neuropathic pain. The most common neuropathic symptoms were paraesthesia/dysesthesia and superficial spontaneous pain. Surprisingly, also patients with neuropathies commonly thought to be painless (such as multifocal motor neuropathy) reported discomfort and painful symptoms. CONCLUSIONS: pain questionnaires should be considered in the clinical evaluation of immune-mediated neuropathies, also when evaluating therapy efficacy, because they may provide clinicians with useful information on painful symptoms and patients' quality of life.

A novel HSPB1 mutation in an Italian patient with CMT2/dHMN phenotype.

Mutations in the gene encoding 27-kDa small heat-shock protein B1 (HSPB1) have been reported in association with Charcot-Marie-Tooth disease type 2F or dHMN type II. We describe an Italian patient with wasting and weakness of distal muscles, involving primarily and mostly the lower limbs and later the upper limbs, in which a novel mutation of HSPB1, T180I, was detected. Electrophysiological evaluation disclosed a pure motor axonal neuropathy. Sural nerve biopsy showed a mild reduction of myelinated fibre density. All these findings suggested a CMT2/dHMN phenotype.

Seipin S90L mutation in an Italian family with CMT2/dHMN and pyramidal signs.

Heterozygous mutations in the Berardinelli-Seip congenital lipodystrophy (BSCL2) gene have been associated with different clinical phenotypes including Silver syndrome/spastic paraplegia 17, distal hereditary motor neuropathy type V, and Charcot-Marie-Tooth disease type 2 (CMT2) with predominant hand involvement. We studied an Italian family with a CMT2 phenotype with pyramidal signs that had subclinical sensory involvement on sural nerve biopsy. Direct sequencing analysis of the BSCL2 gene in the three affected siblings revealed an S90L mutation. This report confirms the variability of clinical phenotypes associated with a BSCL2 Ser90Leu mutation and describes the first Italian family with this mutation.

Epstein-Barr virus antibodies in serum and cerebrospinal fluid from multiple sclerosis, chronic inflammatory demyelinating polyradiculoneuropathy and amyotrophic lateral sclerosis.

Elevated anti-Epstein-Barr virus (EBV) antibody levels are present in serum of Multiple sclerosis (MS) patients but literature lacks of studies comparing anti-EBV antibody levels between MS and other neurological diseases. We evaluate anti-VCA IgG and IgM, anti-EBNA1 IgG, anti-Cytomegalovirus IgG and IgM titres in serum and cerebrospinal fluid (CSF) of 267 MS, 50 Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP) and 88 Amyotrophic Lateral Sclerosis (ALS) patients. We found increased titres of anti-EBV-IgG in serum and CSF of MS subjects as compared to CIDP and ALS patients thus providing additional evidence for a possible involvement of EBV in MS.

Light chain deposition in peripheral nerve as a cause of mononeuritis multiplex in Waldenström's macroglobulinaemia.

Waldenström's macroglobulinaemia is a form of monoclonal IgM gammopathy associated with a rare B-cell lympho-plasmacytic lymphoma, characterized by the involvement of bone marrow, lymph nodes and spleen. Neurological complications involving peripheral nerves are common and different pathogenic mechanisms have been reported. We describe a patient with severe multineuropathy associated with Waldenström's macroglobulinaemia. Nerve biopsy revealed copious light chain deposition which subverted the normal architecture of the endoneurium and epineurium resulting in massive fascicular hyalinosis and epineural arteries disruption, respectively. This report confirms that massive immunoglobulin deposition is one of the several mechanisms of nerve damage in IgM-related neuropathy. Since their recognition has important therapeutical consequences, nerve biopsy is an essential diagnostic tool in patients with an unusual clinical presentation of IgM-related neuropathies.

Triple A syndrome: a novel compound heterozygous mutation in the AAAS gene in an Italian patient without adrenal insufficiency.

Allgrove syndrome (or triple A syndrome) is a rare autosomal recessive disorder characterized by alacrima, achalasia, ACTH-resistant adrenal insufficiency and autonomic/neurological abnormalities. It is caused by mutations in the AAAS gene, located on chromosome 12q13. We describe a 42-year-old patient who presented with neuropathy and was found to have alacrima, achalasia, mild autonomic dysfunction with significant central and peripheral nervous system involvement. She was later diagnosed with oligosymptomatic triple A syndrome. Sequencing of the AAAS gene identified two heterozygous mutations within exon 14 and its donor splice site (p.L430F-c.1288C>T and c.1331+1G>T), one of which is novel. Allgrove syndrome should be suspected in patients with neurological impairment associated with two or more of the main symptoms (alacrima, achalasia or adrenal insufficiency).

Correlations between peripheral blood mononuclear cell production of BDNF, TNF-alpha, IL-6, IL-10 and cognitive performances in multiple sclerosis patients.

The aim of this study was to investigate the role of Brain Derived Neurotrophic Factor (BDNF) and inflammatory factors in the development of cognitive dysfunctions in Multiple Sclerosis (MS). We correlated peripheral blood mononuclear cell (PBMC) production of BDNF, Tumor Necrosis Factor-alpha (TNF-alpha), Interleukin (IL)-6 and IL-10 with performances on specific neuropsychological tasks in a selected series of MS patients. We studied a sample of 30 patients with relapsing-remitting (RR)MS, segregated by gender and matched for age, education, disease duration, type of immunomodulating therapy, degree of disability and overall cognitive status. We found that low BDNF levels were correlated with increased time of execution on a divided attention and visual scanning task whereas high levels of IL-6 were correlated with low Mini Mental State Examination scores. We did not observe any significant correlations between IL-10, TNF-alpha levels and cognitive performances in our patients. In conclusion our study shows a correlation between low BDNF and high IL-6 production by PBMCs and poorer performances in cognitive tasks in RRMS patients suggesting a possible role of these factors in cognitive impairment in MS.

Multiple sclerosis attacks triggered by hyperprolactinemia.

Multiple sclerosis (MS) is a T-cell autoimmune disease of the central nervous system (CNS). Predominance of women in autoimmune diseases suggests that sex hormones may play a role in disease susceptibility. A possible role for prolactin, a neuroendocrine peptide with powerful immunomodulatory properties, is suggested in MS. We describe the case of a 32-year-old man affected by relapsing-remitting MS who experienced the first MS clinical event during the development of a prolactin-secreting adenoma and the only two MS relapses during adenoma recurrence. Prolactin may have facilitated the inflammatory process and triggered MS clinical attacks, suggesting a role of prolactin in immunomodulation and therefore in autoimmune disease course.

T-bet and pSTAT-1 expression in PBMC from coeliac disease patients: new markers of disease activity.

Coeliac disease (CD) is considered a T cell-mediated autoimmune disease, and up-regulation of T-bet and phosphorylated signal transducers and activators of transcription (pSTAT)1, key transcription factors for the development of T helper type 1 (Th1) cells, has been described in the mucosa of patients with untreated CD. Using transcription factor analysis, we investigated whether T-bet and pSTAT1 expressions are up-regulated in the peripheral blood of CD patients and correlate with disease activity. Using flow cytometry, we analysed T-bet, pSTAT1 and pSTAT3 expression in CD4(+), CD8(+) T cells, CD19(+) B cells and monocytes from peripheral blood of 15 untreated and 15 treated CD patients and 30 controls, and longitudinally in five coeliac patients before and after dietary treatment. We evaluated using enzyme-linked immunosorbent assay (ELISA), interferon (FN)-gamma, interleukin (IL)-17 and IL-10 production by peripheral blood mononuclear cell (PBMC) cultures. T-bet expression in CD4(+), CD8(+) T cells, CD19(+) B cells and monocytes and IFN-gamma production by PBMC was higher in untreated than in treated CD patients and controls. pSTAT1 expression was higher in CD4(+)T cells, B cells and monocytes from untreated than from treated CD patients and controls. pSTAT3 was increased only in monocytes from untreated patients compared with CD-treated patients and controls. The data obtained from the longitudinal evaluation of transcription factors confirmed these results. Flow cytometric analysis of pSTAT1 and T-bet protein expression in peripheral blood mononuclear cells could be useful and sensible markers in the follow-up of CD patients to evaluate disease activity and response to dietary treatment.

Tourettism in multiple sclerosis: a case report.

The term Tourettism refers to Tourette Syndrome (TS)-like symptoms which appear secondary to a variety of both acquired and congenital neurological and neuropsychiatric disorders or following an exposure to several drugs. The association between Tourettism and Multiple Sclerosis (MS) is very rare. Only two cases of patients affected by MS who also showed a simple phonic tic and complex vocal tics respectively have been reported. The case here described reports of a 30 year-old woman affected by secondary-progressive MS who developed, 7 years after the onset of the disease, TS-like symptoms which were responsive to quetiapine. At that time her brain MRI, when compared with the previous scan, showed an increased lesion burden and an increased atrophy in the regions around Sylvian fissures. Considering recent findings on TS, the increased atrophy in these strategic brain regions could be responsible for the tics onset in our patient. At the same time, the diffuse involvement of the white matter and the progressive brain atrophy which we observed could have impaired the cortico-striato-thalamo-cortical circuits consistently implicated in the pathogenesis of TS. In conclusion, we can hypothesize that in our case Tourettism and MS could be considered causal related more than coincidentally associated.

LTD-like plasticity induced by paired associative stimulation: direct evidence in humans.

Paired associative stimulation (PAS), in which peripheral nerve stimuli are followed by transcranial magnetic stimulation (TMS) of the motor cortex, may produce a long lasting change in cortical excitability. At an interstimulus interval slightly shorter than the time needed for the afferent inputs to reach cerebral cortex (10 ms), motor cortex excitability decreases. Indirect data support the hypothesis that PAS at this interval (PAS10) involves LTD like-changes in cortical synapses. The aim of present paper was to investigate more directly PAS10 effects. We recorded corticospinal descending volleys evoked by single pulse TMS before and after PAS10 in two conscious subjects who had a high cervical epidural electrode implanted for pain control. These synchronous volleys provide a measure of cortical synaptic activity. PAS10 significantly reduced the amplitude of later descending waves while the earliest descending wave was not modified. Present results confirm the cortical origin of the effect of PAS10.

Reduced cerebral cortex inhibition in dystonia: direct evidence in humans.

OBJECTIVE: A loss of inhibition in central motor circuits resulting in abnormal motor control is the hypothesised cause of dystonia. So far, changes in inhibitory function of cerebral cortex in dystonia, have been revealed only indirectly by recording muscle responses evoked by transcranial magnetic stimulation (TMS) of the brain. The aim of present study was to evaluate more directly cerebral cortex changes in dystonia. We had the almost unique opportunity to record directly motor cortex output after brain stimulation, in a dystonic patient who had epidural electrodes implanted in the upper cervical cord. METHODS: We evaluated descending activity evoked by single and paired pulse TMS together with the inhibitory effects produced by afferent stimuli on TMS evoked activity, and compared the results with those obtained in thirteen subjects with no central nervous system abnormality who also had cervical spinal electrodes. RESULTS: The intrinsic inhibitory activity produced by paired TMS of the motor cortex, and the inhibitory effects produced by afferent inputs, were suppressed in the patient with dystonia. CONCLUSIONS: These findings provide a direct evidence of the abnormality in motor cortex inhibitory systems in dystonia. SIGNIFICANCE: The abnormality in cortical inhibitory system might have a role in the pathophysiology of dystonia.

Does exposure to extremely low frequency magnetic fields produce functional changes in human brain?

Behavioral and neurophysiological changes have been reported after exposure to extremely low frequency magnetic fields (ELF-MF) both in animals and in humans. The physiological bases of these effects are still poorly understood. In vitro studies analyzed the effect of ELF-MF applied in pulsed mode (PEMFs) on neuronal cultures showing an increase in excitatory neurotransmission. Using transcranial brain stimulation, we studied noninvasively the effect of PEMFs on several measures of cortical excitability in 22 healthy volunteers, in 14 of the subjects we also evaluated the effects of sham field exposure. After 45 min of PEMF exposure, intracortical facilitation produced by paired pulse brain stimulation was significantly enhanced with an increase of about 20%, while other parameters of cortical excitability remained unchanged. Sham field exposure produced no effects. The increase in paired-pulse facilitation, a physiological parameter related to cortical glutamatergic activity, suggests that PEMFs exposure may produce an enhancement in cortical excitatory neurotransmission. This study suggests that PEMFs may produce functional changes in human brain.

Associative motor cortex plasticity: direct evidence in humans.

Previous studies have shown that paired associative stimulation (PAS) protocol, in which peripheral nerve stimuli are followed by transcranial magnetic stimulation (TMS) of the motor cortex at intervals that produce an approximately synchronous activation of cortical networks, enhances the amplitude of motor evoked potentials (MEPs) evoked by cortical stimulation. Indirect data support the hypothesis that the enhancement of MEPs produced by PAS involves long-term potentiation like changes in cortical synapses. The aim of present paper was to investigate the central nervous system level at which PAS produces its effects. We recorded corticospinal descending volleys evoked by single pulse TMS of the motor cortex before and after PAS in 4 conscious subjects who had an electrode implanted in the cervical epidural space for the control of pain. The descending volleys evoked by TMS represent postsynaptic activity of corticospinal neurones that can provide indirect information about the effectiveness of synaptic inputs to these neurones. PAS significantly enhanced the amplitude of later descending waves, whereas the earliest descending wave was not significantly modified by PAS. The present results show that PAS may increase the amplitude of later corticospinal volleys, consistent with a cortical origin of the effect of PAS.

T-bet, pSTAT1 and pSTAT3 expression in peripheral blood mononuclear cells during pregnancy correlates with post-partum activation of multiple sclerosis.

In pregnant women affected by multiple sclerosis (MS) we observed increased percentages of CD4(+)CD25(+)Foxp3(+) T regulatory cells at the 1st and the 2nd trimester of gestation that was associated with a decreased T-bet expression in CD4(+) T cells. In women showing clinical relapse and/or new lesions at MRI after delivery we found, a higher expression of T-bet, pSTAT1 and pSTAT3 in CD4(+), CD8(+) T cells and CD14(+) cells, associated with an increase of IFNgamma and IL17 production by PBMC at the 3rd trimester of gestation and after delivery. Our data suggest that the expansion of circulating CD4(+)CD25(+)Foxp3(+) regulatory T cells and the lower expression of T-bet in CD4(+) T cells may account for the decreased MS activity during pregnancy. The expression of T-bet, pSTAT1 and pSTAT3 in peripheral blood CD4(+) and CD8(+) T cells and monocytes could be useful to identify MS patients who will develop a relapse after delivery.

Stroke in critically ill patients.

Advances in critical care medicine have led to improved survival rates among patients admitted to the Intensive Care unit (ICU), but complications experienced during admittance in an ICU may influence long-term outcome and the neurocognitive state of these patients. Coagulation disorders, glucose intolerance, diabetes, pro-inflammatory state and underlying severe pathologies are common risk factors for stroke development in ICU patients. Stroke may result in very serious consequences like motor function impairment, neglect and aphasia, but in some cases, stroke may not result in any clinical sign in acute phase. Recently, more attention has been given to this condition called ''silent stroke.'' ''Silent stroke'' could be the foundation of the development of neurocognitive impairment and vascular dementia. In ICU survivors, approximately 1/3 of patients or more will develop chronic neurocognitive impairment. With the advent of sensitive techniques for brain imaging, silent brain lesions, including brain infarct and white matter changes, have been frequently recognized. Until now, epidemiological studies in this field evaluating incidence and consequences of stroke in ICU setting are lacking, and prospective studies are required to evaluate the impact of this condition on the quality of life, neurocognitive outcome and mortality of ICU patients. We believe that when stroke occurs in critically ill patients, more attention is typically given to the underlying pathologies than stroke, and this may influence the long-term outcome. Guidelines for the early management of stroke, commonly used in Stroke Units, should be followed, even in critically ill patients in an ICU setting.