Reorganization of the motor cortex in a patient with congenital hemiparesis and mirror movements.

Abnormal branching of corticospinal fibers from the unaffected motor cortex is responsible for mirror movements in patients with congenital hemiparesis, but it is unknown which mechanisms enable these patients to lateralize motor activity. Using multiunit electromyographic analysis and transcranial magnetic stimulation, the authors provide evidence for nonbranched crossed and uncrossed corticospinal projections and intracortical inhibition of the mirror hand. They propose that this remarkable reorganization of the unaffected motor cortex helps these patients to reduce mirror movements.

The "Harlequin Sign". Case description and review of the literature.

Asymmetrical facial sweating and flushing has been named the "Harlequin Sign". This is a rare feature, as evident from only 12 cases described up to date. The "Harlequin Sign" represents a local autonomic dysfunction due to a cervical sympathetic deficit located at the pre or postganglionic level on the non-flushing side. We observed slow onset and progression of the "Harlequin Sign" in a 19-year-old man, with preexisting slight miosis on the non-flushing side. The differential diagnosis included other forms of dysautonomia and a secondary origin of this partial Horner's syndrome. Both pupils normally reacted to light, convergence, and pilocarpine eye-drop instillation, but the affected side showed supersensitivity to phenylephrine. Deep tendon reflexes were normal, thus excluding Adie's syndrome. The absence of cholinergic supersensitivity in the iris muscles indicated normal function of the ciliary ganglion and excluded the ocular parasympathetic deficit, also evident for the coexisting Horner's syndrome. The clinical features could be explained by assuming that the lesion was located at the level of postganglionic sympathetic fibers, probably due to trans-synaptic postganglionic neuronal degeneration at the level of the stellate ganglion, thus determining the onset of the hemifacial symptoms.

Blood pressure and heart rate relationship in normotensive and hypertensive subjects.

A twenty-four-hour blood pressure (BP) monitoring was performed in 20 normotensive and 20 hypertensive subjects, matched by sex and age. Blood pressure and heart rate (HR) variability were evaluated both as absolute and percent standard deviation. In agreement with the literature no significant difference in HR and BP variability was observed between the two groups. The linear regression between HR and BP values was evaluated in both groups. The authors observed a significant difference in the relationship between these two cardiovascular variables between the two groups. In the hypertensive group the cardiovascular control of HR and BP showed a different relationship than in normotensive subjects, suggesting a different neurovegetative modulation.

Mitotic activity in colorectal mucosa of healthy subjects in two Italian areas with different dietary habits.

The proliferative activity was evaluated in colorectal biopsies of 39 healthy subjects living in two distinct geographical areas, Trieste in northern and Florence in central Italy. Subjects living in Trieste had a significantly higher mitotic activity compared with subjects living in Florence (mitoses/cells counted x 100 were 0.17 +/- 0.04 in Trieste and 0.089 +/- 0.02 in Florence). The results of a dietary questionnaire also showed that subjects in Trieste consumed significantly fewer starches, fibers, nitrites, and proteins. However, no correlation was evident between the consumption of these nutrients and intestinal proliferation.

Detection of normotension, borderline and hypertension cutoffs in a population evaluated by non invasive blood pressure monitoring.

The 24-hour blood pressure (BP) average value in normotensive and hypertensive subjects is not defined. In 329 subjects three occasional blood pressure data were measured. The same day a non invasive 24-hour blood pressure monitoring was performed. The average of the occasional blood pressure and the average of the 24-hour blood pressure data were compared. In many cases the occasional blood pressure average was not strictly linked with the 24-hour blood pressure average. A statistical procedure (K-Means Cluster Analysis) was performed separately on occasional blood pressure values and on the hourly blood pressure average of the whole day. By this method three clusters of subjects were selected to evaluate the occasional and the 24-hour blood pressure cluster's cutoffs. The cluster's blood pressure cutoffs evaluated on occasional blood pressure values were not dissimilar from the blood pressure values suggested by literature for normotensive, borderline and hypertensive groups. The K-Means Clusters Analysis seems an interesting statistical method to research the subsets in a population evaluated by 24-hour blood pressure monitoring. We suggest that the 24-hour BP cutoffs evaluated in the three cluster groups may be considered as indicative for a clinical diagnosis of normotensive, borderline and hypertensive state.