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Cardiac syndrome X (CSX) is characterized by effort angina, ST-segment depression during stress tests and normal coronary arteries. Abnormal nociception was suggested in these patients by studies showing a reduced cardiac pain threshold; furthermore, we recently found a lack of habituation to pain stimuli using recording of laser evoked potentials (LEPs). In CSX patients with severe angina, spinal cord stimulation (SCS) was shown to improve symptoms. In this study we investigated whether, in these patients, SCS has any effects on the excitability of the nociceptive system, assessed by LEPs recording. We studied 16 CSX patients (61.6+/-7 years; 4 men) who underwent SCS for refractory angina. Cortical LEPs were recorded during stimulation of the chest and right-hand during active SCS (SCS-ON) and in the absence of SCS (SCS-OFF), using a randomized cross-over design. Three sequences of painful stimuli were applied at each site during each test. During the first sequence of chest stimuli, the N2/P2 LEP amplitude was higher during the SCS-ON, compared to the SCS-OFF phase (18.2+/-7.8 vs. 11.5+/-4.4 microV, P=0.006). The N2/P2 amplitude did not change significantly across the three stimulation sequences during the SCS-OFF phase (P=0.22), whereas it decreased progressively during the second and third sequence (to 87.1+/-29.5% and 76.4+/-24.1%, respectively) compared with the first sequence, during the SCS-ON phase (P=0.014). Similar results were observed during right-hand stimulation. Our study shows that in CSX patients SCS is able to restore habituation to peripheral pain stimuli. This effect might contribute to restore the ability of CSX patients to better tolerate cardiac pain.

Objective: To determine the diagnostic value of motor evoked potentials (MEPs) in the diagnosis of lumbosacral cord disorders., Methods: MEPs in 37 patients with sensory and motor deficits in the lower limbs were studied. MRI demonstrated spinal cord involvement in 10 patients and cauda equina lesions in 27 patients. A double determination of central motor conduction time (CMCT), calculated as the difference between the latencies of responses evoked by cortical and paravertebral magnetic stimulation and as the difference between the latency of cortical MEP and the total peripheral conduction time calculated from the F-wave latency, enabled discrimination between a delay along the proximal root and a delay along the corticospinal tract. An abnormality of the CMCT calculated with both techniques is indicative of central motor pathway damage, whereas an abnormality of the CMCT calculated from the latency of responses evoked by paravertebral magnetic stimulation associated with a normal CMCT calculated from the F-wave latency suggests a cauda equina lesion., Results: Neurophysiologic findings strongly correlated with the lesion site documented by MRI (cauda equina or lumbosacral cord). All patients with MR evidence of cord involvement had an abnormality of CMCT calculated with both methods, suggesting a lesion of central motor pathways. Clinical examination often failed to document a spinal cord lesion, suggesting pure peripheral involvement in 5 of the 10 patients with MR evidence of cord lesion., Conclusion: Motor evoked potential recording is an accurate and easily applicable test for the diagnosis of lumbosacral spinal cord lesions.

Low- and high-frequency repetitive transcranial magnetic stimulation (rTMS) of the motor cortex results in lasting changes of excitatory neurotransmission. We investigated the effects of suprathreshold 1 Hz rTMS on brain derived neurotrophic factor (BDNF) plasma levels in 10 healthy subjects and effects of either 1 Hz or 20 Hz rTMS in four amyotrophic lateral sclerosis (ALS) patients. BDNF levels were progressively decreased by 1 Hz rTMS in healthy subjects; there was no effect of 1 Hz rTMS on BDNF plasma levels in ALS patients, an effect probably due to the loss of motor cortex pyramidal cells. High frequency rTMS determined a transitory decrease in BDNF plasma levels. Cumulatively these findings suggest that rTMS might influence the BDNF production by interfering with neuronal activity.

Objective: To examine the characteristics of thymoma when associated with MG and to evaluate those conditions that can complicate management and affect survival., Methods: The study includes 207 myasthenic patients who were operated on for thymoma, with at least 1-year follow-up from surgery. MG severity and response to treatment, the occurrence of paraneoplastic diseases and extrathymic malignancies, thymoma histologic types and stages, adjuvant therapy, tumor recurrences, and causes of death were recorded., Results: MG-associated thymoma was predominantly of B type and was invasive in the majority of patients. MG was generally severe, and most patients remained dependent on immunosuppressive therapy. Other paraneoplastic disorders and extrathymic malignancies were found in 9.66 and 11.11% of patients. Thymoma recurrences occurred in 18 of 115 patients with invasive tumors (15.65%) and were often associated with the onset/aggravation of autoimmune diseases. On completion of the study, MG and thymoma accounted for a similar mortality rate., Conclusions: Thymoma should be considered as a potentially malignant tumor requiring prolonged follow-up. The presence of myasthenic weakness can still complicate its management. Thymoma-related deaths are bound to outnumber those due to MG in the future.

Background: A recently devised test of motor cortex excitability (short latency afferent inhibition) was shown to be sensitive to the blockade of muscarinic acetylcholine receptors in healthy subjects. The authors used this test to assess cholinergic transmission in the motor cortex of patients with AD., Methods: The authors evaluated short latency afferent inhibition in 15 patients with AD and compared the data with those of 12 age-matched healthy controls., Results: Afferent inhibition was reduced in the patients (mean responses +/- SD reduced to 85.7% +/- 15.8% of the test size) compared with controls (mean responses +/- SD reduced to 45.3% +/- 16.2% of the test size; p < 0.001, unpaired t-test). Administration of a single oral dose of rivastigmine improved afferent inhibition in a subgroup of six patients., Conclusions: The findings suggest that this method can be used as a noninvasive test of cholinergic pathways in AD. Future studies are required to evaluate whether short latency afferent inhibition measurements have any consistent clinical correlates.

At a young age, ischemic stroke is an uncommon event in which prothrombotic factors are likely to play an important role. In 202 referred cases, 105 men and 97 women, median age 39 years (range, 3 to 50), with a history of ischemic stroke and in 1036 age frequency-matched apparently healthy individuals from the same ethnic background, we have investigated whether inherited prothrombotic conditions increase the risk of ischemic stroke. Neither abnormal plasma levels of natural anticoagulants and fibrinogen nor significant increase of the prothrombin A20210 allele was found in stroke cases compared with controls. Hypertension (odds ratio [OR], 22.61), male sex (OR, 2.30), smoking (OR, 2.78) and alcohol habits (OR, 0.14), a personal history of venous thromboembolism (OR, 4.53), a family history of stroke (OR, 1.93), high circulating levels of fibrinogen (P=0.0190), and total cholesterol (P=0.101) were all independently associated with ischemic stroke. Compared with noncarriers, carriers of the factor V (FV) Leiden mutation (OR, 2.56), and to a lesser extent, of the methylenetetrahydrofolate reductase (MTHFR) TT genotype (OR, 1.60), had an independent higher estimated risk of having a history of ischemic stroke. The relationship with the FV Leiden mutation was greater in women (OR, 3.95). Thus, in addition to established determinants, FV Leiden mutation is independently associated with the occurrence of ischemic stroke in this setting. The greater association in women suggests the possibility of an interaction of this genotype with female hormones.