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P Tonali

Publications and source records attributed to P Tonali.

At least 37 records · Page 2Linked to original sources
PubMed2005

Neurophysiological predictors of long term response to AChE inhibitors in AD patients.

BACKGROUND: In vivo evaluation of cholinergic circuits of the human brain has recently been introduced using a transcranial magnetic stimulation (TMS) protocol based on coupling peripheral nerve stimulation with motor cortex TMS (short latency afferent inhibition, SAI). SAI is reduced in Alzheimer's disease (AD) and drugs enhancing cholinergic transmission increase SAI. METHODS: We evaluated whether SAI testing, together with SAI test-retest, after a single dose of the acetylcholinesterase (AChE) inhibitor rivastigmine, might be useful in predicting the response after 1 year treatment with rivastigmine in 16 AD patients. RESULTS: Fourteen AD patients had pathologically reduced SAI. SAI was increased after administration of a single oral dose of rivastigmine in AD patients with abnormal baseline SAI, but individual responses to rivastigmine varied widely, with SAI change ranging from an increase in inhibition of approximately 50% of test size to no change. Baseline SAI and the increase in SAI after a single dose of rivastigmine were correlated with response to long term treatment. A normal SAI in baseline conditions, or an abnormal SAI in baseline conditions that was not greatly increased by a single oral dose of rivastigmine, were invariably associated with poor response to long term treatment, while an abnormal SAI in baseline conditions in conjunction with a large increase in SAI after a single dose of rivastigmine was associated with good response to long term treatment in most of the patients. CONCLUSIONS: Evaluation of SAI may be useful for identifying AD patients likely to respond to treatment with AChE inhibitors.

Aged↗
PubMed2004

Back pain in pregnancy: 1-year follow-up of untreated cases.

Back Pain (BP) is one of the most frequent symptoms during the last period of pregnancy, and high incidence has been described in several studies. Until now no wide, multicenter and prospective clinical studies on the natural course of BP after pregnancy have been available. We performed a multicenter follow-up study in a sample of pregnant women using the Italian validated version of the Roland questionnaire to assess the evolution of BP after pregnancy and identify prognostic factors. Each center had to re-evaluate at least 75% of the initially enrolled women, with latency of 1 year after delivery. At the follow-up, we acquired substantial clinical data concerning the post-delivery period. The evaluation of symptom evolution was based on the Roland questionnaire. At follow-up, 53% of re-evaluated women had no BP symptoms. Moreover, there was a significant improvement of patient-oriented assessment in women who suffered BP after delivery. With regard to the predictive factors, the presence of BP before pregnancy implied a 3.1-fold higher probability of improvement after delivery. In conclusion, women without history of BP before pregnancy and who complain of these symptoms during pregnancy require greater attention, because they have a lower possibility for improvement. Conversely, in women with a history of BP, pregnancy represents a transient period of worsening symptoms, probably due to the temporary para-physiological mechanical condition.

Back Pain↗
PubMed2004

Tumor necrosis factor alpha serum levels and inflammatory response in acute ischemic stroke patients.

Experimental evidence indicates that tumor necrosis factor alpha (TNF-alpha) is involved in brain damage following ischemic injury. The present study was designed to monitor serum TNF-alpha levels in acute stroke patients and to correlate TNF-alpha levels with lesion size, neurological impairment and vascular risk factors. In 41 patients with ischemic stroke, serum TNF-alpha levels were serially measured by a solid enzyme amplified sensitivity immunoassay (EASIA) in the first 10 days after stroke onset. Serum fibrinogen and C-reactive protein (CRP), white blood cell (WBC) and neutrophil counts were determined on the same days to monitor acute phase response changes. Lesion size was calculated on computed tomograms by a computer-assisted procedure. Neurological impairment was evaluated on the Canadian Neurological Scale. Forty age-matched subjects were used as controls. Compared to baseline, TNF-alpha levels significantly increased during the study ( p=0.0001), peaking on day 7. Peak TNF-alpha levels did not correlate with neurological impairment or lesion size. Multivariate analysis showed that sex, age, vascular risk factors and infectious complications did not influence TNF-alpha levels. Fibrinogen, CRP, WBC and neutrophil concentrations increased, indicating an acute phase response occurred after stroke. In conclusion, serum TNF-alpha levels showed an early and prolonged increase after stroke onset, unrelated to lesion size, neurological impairment, age, sex, vascular risk factors or infectious complications. Serum increase of TNF-alpha may be explained as part of the acute phase response occurring in stroke patients.

Aged↗
PubMed2004

Topiramate in migraine prophylaxis: a randomised double-blind versus placebo study.

The objectives of this paper are to evaluate the efficacy and tolerability of topiramate, given at the dose of 100 mg/day, in the prophylactic treatment of migraine. The hypothesis that migraine is the result of a condition of neuronal hyperexcitability and the quest for drugs that are able to limit the number of crises justifies the attempt to utilise the new antiepileptic drugs in the prophylaxis of this pathology, which is so important due to its high prevalence and due to the high disability it causes. The study was randomised double-blind versus placebo, lasting 16 weeks, and was preceded by a run-in period of 4 weeks. One hundred and fifteen patients were randomly allocated to treatment with topiramate (TPM) or placebo: 35 patients completed the study in the TPM group and 37 patients in the placebo group. At the end of the double-blind phase of study, in the TPM group, we recorded a significant reduction in the frequency of migraine crises (from 5.26 at baseline to 2.60 in the last 4 weeks), a significant reduction in the quantity of symptomatic drugs taken as compared to the placebo control group (from 6.17+/-1.80 SD to 2.57+/-0.80) and a significant downward trend in the number of days of disability over the 16-week period of therapy. In the TPM group, side effects were transient and well tolerated. TPM has thus proven its efficacy and tolerability in the prophylaxis of migraine.

Adult↗
PubMed2004

Parietal generators of low- and high-frequency MN (median nerve) SEPs: data from intracortical human recordings.

OBJECTIVE: To identify low and high-frequency median nerve (MN) somatosensory evoked potential (SEP) generators by means of chronically implanted electrodes in the parietal lobe (SI and neighbouring areas) of two epileptic patients. METHODS: Wide-pass short-latency and long-latency SEPs to electrical MN stimulation were recorded in two epileptic patients by stereotactically chronically implanted electrodes in the parietal lobe (SI and neighbouring areas). To study high-frequency responses (HFOs) an off-line digital filtering of depth short-latency SEPs was performed (500-800 Hz, 24 dB roll-off). Spectral analysis was performed by fast Fourier transform. RESULTS: In both patients we recorded a N20/P30 potential followed by a biphasic N50/P70 response. A little negative response in the 100 ms latency range was the last detectable wide-pass SEP in both patients. Two HFOs components (called iP1 and iP2) were detected by mere visual analysis and spectral analysis, and were supposed to be originated within the parietal cortex. CONCLUSIONS: This was the very first study that recorded wide bandpass and high frequency SEPs by electrodes, exploring both the lateral and the mesial part of the parietal lobe and particularly that of the post-central gyrus.

Adult↗
PubMed2004

Occurrence of nerve entrapment lesion in chronic inflammatory demyelinating polyneuropathy.

OBJECTIVE: To evaluate the occurrence of nerve entrapment syndrome in chronic inflammatory demyelinating polyneuropathy (CIDP). METHODS: We retrospectively evaluated neurophysiologic results of 41 (25 male and 16 female, mean age 49.8, range 11-87) patients with CIDP. We evaluated the frequency of focal neurophysiologic lesion at entrapment site distinguishing two kinds of lesion: (a) true entrapment; and (b) false entrapment on the basis of nerve conduction results. RESULTS: Occurrence of focal aggression within the entrapment site is similar to that out of the entrapment site in all examined nerves. CONCLUSIONS: The entrapment sites are not an elective zone of focal autoimmune aggression in CIDP. Therefore, in CIDP patients a true entrapment, neurophysiologically demonstrated, could be a concomitant pathology and if a severe and persistent entrapment worsens functional deficit and symptoms, a surgical decompression could be useful.

Adolescent↗
PubMed2004

Adverse effects of GH self administration on peripheral nerve. A case report.

To our knowledge there is no evidence of multientrapment neuropathy related to growth hormone (GH) administration. We observed the case of a 45-year-old bodybuilder complaining of paresthesias and dysesthesias of the hands and feet after self-administration of high-dose of recombinant GH therapy. The patient complained of transitory symptoms after each cycle of GH therapy. The electrodiagnosis showed: 1) moderate right carpal tunnel syndrome (CTS) and minimal left CTS; 2) mild right ulnar entrapment at elbow; 3) a reduction of motor nerve conduction velocity of the left ulnar nerve across elbow; 4) a reduction of the amplitude of the sensory nerve action potential of the left ulnar nerve in digit-wrist segment; 5) the absence of the ulnar F wave bilaterally registering from abductor digiti minimus. Our data suggest a multiple entrapment condition of the upper limbs; furthermore, based on the history (paresthesia at feet), we can hypothesize a mild involvement of distal sensory fibres in the legs (neurophysiologically negative). The anecdotal history and neurophysiological findings of this case suggest an increased awareness to the adverse effects of GH on peripheral nerve.

Carpal Tunnel Syndrome↗
PubMed2003

The human supplementary motor area-proper does not receive direct somatosensory inputs from the periphery: data from stereotactic depth somatosensory evoked potential recordings.

Somatosensory evoked potentials to median nerve (MN) stimulation were recorded by stereotactically implanted electrodes in the frontal lobe of two epileptic patients in order to evaluate whether short-latency cortical responses could be generated in the supplementary motor area (SMA)-proper. In both patients two potentials, called P20 and N30 responses, showed a decreasing amplitude from the most superficial to the deepest contacts and were recorded in the white as well in the grey matter of the frontal lobe. Furthermore, no phase reversal of both P20 and N30 potentials was identifiable along electrode trajectories. Our results suggest that short-latency somatosensory evoked responses recorded in the SMA-proper contralateral to MN stimulation are volume conducted from remote cortical generators.

Adult↗
PubMed2003

Cervical cord dysfunction during neck flexion in Hirayama's disease.

Neck flexion may play a role in the pathogenesis of Hirayama disease. Upper limb somatosensory evoked potentials were recorded in five patients with Hirayama disease, six patients with ALS, and 14 healthy subjects. Neck flexion caused a significant amplitude decrease of the N13 cervical response only in patients with Hirayama disease. Direct cord compression or microvascular changes can in theory account for this position-related dysfunction.

Adolescent↗
PubMed2003

Reduced habituation to experimental pain in migraine patients: a CO(2) laser evoked potential study.

The habituation to sensory stimuli of different modalities is reduced in migraine patients. However, the habituation to pain has never been evaluated. Our aim was to assess the nociceptive pathway function and the habituation to experimental pain in patients with migraine. Scalp potentials were evoked by CO(2) laser stimulation (laser evoked potentials, LEPs) of the hand and facial skin in 24 patients with migraine without aura (MO), 19 patients with chronic tension-type headache (CTTH), and 28 control subjects (CS). The habituation was studied by measuring the changes of LEP amplitudes across three consecutive repetitions of 30 trials each (the repetitions lasted 5 min and were separated by 5-min intervals). The slope of the regression line between LEP amplitude and number of repetitions was taken as an index of habituation. The LEPs consisted of middle-latency, low-amplitude responses (N1, contralateral temporal region, and P1, frontal region) followed by a late, high-amplitude, negative-positive complex (N2/P2, vertex). The latency and amplitude of these responses were similar in both patients and controls. While CS and CTTH patients showed a significant habituation of the N2/P2 response, in MO patients this LEP component did not develop any habituation at all after face stimulation and showed a significantly lower habituation than in CS after hand stimulation. The habituation index of the vertex N2/P2 complex exceeded the normal limits in 13 out of the 24 MO patients and in none of the 19 CTTH patients (P<0.0001; Fisher's exact test). Moreover, while the N1-P1 amplitude showed a significant habituation in CS after hand stimulation, it did not change across repetitions in MO patients. In conclusion, no functional impairment of the nociceptive pathways, including the trigeminal pathways, was found in either MO or CTTH patients. But patients with migraine had a reduced habituation, which probably reflects an abnormal excitability of the cortical areas involved in pain processing.

Adult↗
PubMed2003

Influence of cholinergic circuitries in generation of high-frequency somatosensory evoked potentials.

OBJECTIVE: High-frequency oscillations (HFOs) evoked by upper limb stimulation reflect highly synchronised spikes generated in the somatosensory human system. Since acetylcholine produces differential modulation in subgroups of neurons, we would determine whether cholinergic drive influences HFOs. METHODS: We recorded somatosensory evoked potentials (SEPs) from 31 scalp electrodes in 7 healthy volunteers, before and after single administration of rivastigmine, an inhibitor of central acetylcholinesterase. Right median nerve SEPs have been analysed after digital narrow bandpass filtering (500-700 Hz). Raw data were further submitted to Brain Electrical Source analysis (BESA) to evaluate the respective contribution of lemniscal, thalamic and cortical sources. Lastly, we analysed by Fast Fourier transform spectral changes after drug administration in the 10-30 ms latency range. RESULTS: Rivastigmine administration caused a significant increase of HFOs in the 18-28 ms latency range. Wavelets occurring before the onset latency of the conventional N20 SEP did not show any significant change. A similar increase concerned the strength of cortical dipolar sources in our BESA model. Lastly, we found a significant power increase of the frequency peak at about 600 Hz in P3-F3 traces after drug intake. CONCLUSIONS: Our findings demonstrate that the cortical component of HFOs is significantly enhanced by cholinergic activation. Pyramidal chattering cells, which are capable to discharge high-frequency bursts, are mainly modulated by cholinergic inputs; by contrast, acetylcholine does not modify the firing rate of fast-spiking GABAergic interneurons. We thus discuss the hypothesis that cortical HFOs are mainly generated by specialised pyramidal cells.

Acetylcholine↗
PubMed2003

Incidence of first-ever ischemic and hemorrhagic stroke in a well-defined community of southern Italy, 1993-1995.

Most epidemiological surveys in the Italian population, have concentrated on areas of northern and central Italy. The incidence of the first-ever ischemic and hemorrhagic strokes in a well-defined population of the province of Foggia, a rural area of southern Italy, over a 3-year period has been investigated, to compare the occurrence of stroke by type in this and other areas. A retrospective study in a local health district (USL FG3) in the province of Foggia was conducted and all cases of first-ever cerebral infarction (CI) and intracerebral hemorrhage (ICH) in the local population (41 269) from January 1, 1993 to December 31, 1995 have been investigated. Case ascertainment was performed by a chart review in the two local hospitals and examination of death certificates. General practitioners were also asked to report on non-hospitalized cases suffering a stroke during the study period. Patients with recurrent stroke, unclassifiable stroke, transient ischemic attacks and subarachnoid hemorrhage were excluded. Risk factors for stroke and 30-day mortality were investigated. The rates were standardized to the Italian population (57 138 489, 1991 census). During the 3-year study period, 202 patients had a first-ever ischemic or hemorrhagic stroke (66 in 1993, 69 in 1994 and 67 in 1995). Of these, 174 (86.1%) had cerebral ischemia, accounting for 57, 60 and 57 cases in the three index years. The overall crude annual incidence of CI and ICH was 1.60, 1.67 and 1.62 of 1000 for 1993, 1994 and 1995, respectively. The corresponding standardized incidences rates were 2.0, 2.10 and 2.06 of 1000. The rate was 0.11 in patients <55 years of age, and 1.97, 7.01, 13.52, and 25.34 at ages 55-64, 65-74, 75-84, and 85+ years for the entire period; the 30-day mortality was 27.2, 21.7, and 15% for 1993, 1994, and 1995, respectively. Hypertension (45.9%), diabetes (26.4%) and atrial fibrillation (16.6%) were the most common risk factors. The incidence of CI and ICH was similar to that of most other Italian studies. It was constant during the 3-year period, and mostly involved older people.

Aged↗
PubMed2002

Long-term follow up of subthalamic nucleus stimulation in Parkinson's disease.

Twenty-two patients with PD received bilateral implants for high frequency stimulation of the subthalamic nucleus. The patients were treated for more than 1 year (up to 36 months). At the last visit, the Unified Parkinson Disease Rating Scale (UPDRS) motor score without medication improved by 50.2% (p < 0.001) and the UPDRS activities of daily living score improved by 68.4% (p < 0.001). The most common long-lasting adverse events were hypophonia and dysarthria; transient events were increased sexuality and mania. The surgical procedure induced transient intraoperative psychosis in seven patients.

Activities of Daily Living↗
PubMed2002

Patient-oriented assessment of back pain in pregnancy.

Back pain is a common symptom in women during the last period of pregnancy. Only a few studies using validated patient-oriented tools have been undertaken on this topic. We report on a multicenter study on back pain in women during the last period of pregnancy, which involved seven Italian institutions. Seventy-six women in their 8th and 9th months were studied using the Italian validated version of the Roland questionnaire -- a disease-specific patient-oriented tool for low back pain. Sixty-two percent of the women had gone through at least one previous pregnancy, and clinical data concerning both the period before all pregnancies and the period before the current pregnancy were acquired. The study found that 31% of the women had no back pain symptoms (Roland score 0), 40% scored from 1 to 4, 21% scored from 5 to 10, and 8% scored more than 10. With regard to the predictive factor, history of back pain and sciatica before the pregnancy were found to be associated with occurrence of back pain symptoms during pregnancy. Unexpectedly, our results showed that male sex of the fetus seems to be related to occurrence of back pain symptoms during pregnancy. However, back pain was not associated with having gone through previous pregnancies, nor was the Roland score related to the weight before pregnancy or to increment of weight during pregnancy. Evaluation of the patient's perspective made it possible to identify predictive factors for occurrence of back pain, thereby furnishing important information for the clinical approach to pregnancy.

Adult↗