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An ethnopharmacological survey was used to compare the medicinal plants most frequently recommended by herbalists, naturopaths, and other traditional practitioners in Moroccan and Canadian socio-economical settings. Striking differences in traditional pharmacopoeias were noted between Morocco and the Canadian province of Quebec, with only one plant, garlic, on both lists of the top 20 most frequently recommended plants. Therapeutic indications, however, showed more similarities with rosemary, lavender, oregano, and white mugwort being recommended against gastrointestinal upset/liver ailments in Morocco, as compared with chamomile, milk thistle, linden and dandelion for similar indications in Quebec. Central nervous system disorders were the second most important indications for medicinal plants (including St. John's wort, chamomile, ginkgo, valerian, and linden) in Quebec as compared with cold/flu/cough for plants indicated in the Moroccan survey (including oregano, lavender, black cumin, Syrian ...

Restless legs syndrome (RLS) is a common sleep-related disorder principally characterised by leg paresthesia associated with an irresistible urge to move. A majority of RLS patients experience periodic leg movements during sleep (PLMS) and wakefulness. Pharmacological evidence suggests that RLS-PLMS may be caused by a central nervous system dopaminergic (DA) dysfunction. The aim of the present study was to evaluate the striatal pre- and postsynaptic DA status in patients suffering from both RLS and PLMS, by means of [123I] beta-CIT and [123I]IBZM SPECT respectively. Ten drug-naïve patients and ten age-matched controls participated in this study. All participants were recorded for at least one night of polysomnography before the SPECT studies. No difference was seen in DA transporter ([123I] beta-CIT) binding between RLS-PLMS patients (MD=4.89) and controls (MD=4.81; p=0.81). The study of the striatal D2-receptor binding ([123I]IBZM) revealed a significantly lower binding in patients (MD= 1.72) compared with controls (MD=1.85; p=0.006). These results support the hypothesis that a central DA dysfunction is involved in the physiopathology of RLS-PLMS. Several mechanisms may be responsible for the decrease of the D2-receptor binding. However, since [123I] beta-CIT binding is normal, a decreased number of D2-receptors or a decreased affinity of D2-receptors for [123I]IBZM is more likely than an increased level of synaptic DA with attendant downregulation of D2-receptors.

The present study examined, in the superior colliculus (SC) of anaesthetised cats, the functional connectivity between superficial-layer neurones (SLNs) and tectoreticular neurones (TRNs: collicular output cells). TRNs were antidromically identified by electrical stimulation of the predorsal bundle. The auto- and cross-correlation histograms of visual responses of both types of neurones were recorded and analysed. A delayed, sharp peak in cross-correlograms allowed us to verify whether SLN and TRN cells were coupled; in addition, oscillatory activities were compared to verify if rhythmic responses of SLN sites were transmitted to TRN sites. We found that oscillatory activity was rarely observed in spontaneous activity of superficial (1/74) and TRN sites (1/48). Moving light bars induced oscillation in 31% (23/74) of the superficial-layer and in 23% (11/48) of the TRN sites. The strength of the rhythmic responses was determined by specific ranges of stimulus velocity in 83% (19/23) and 64% (7/11) of oscillating SLN and TRN sites, respectively. Frequencies of oscillations ranged between 5 and 125 Hz and were confined, for 53% of the cells, to the 5-20 Hz band. Thus, the band-width of frequencies of the stimulus-related oscillations in the superior colliculus was broader than the gamma range. Analysis of cross-correlation histograms revealed a significant predominant peak with a mean delay of 2.7+/-0.9 ms in 46% (17/37) of SLN-TRN pairs. Most correlated SLN-TRN pairs (88%: 15/17) had superimposed receptive fields, suggesting they were functionally interconnected. However, individual oscillatory frequencies of correlated and oscillatory SLN and TRN cells were never the same (0/8). Together, these results suggest that the neurones in collicular superficial layer contact TRNs and, consequently, support the idea that the superficial layers contribute to collicular outputs producing eye- and head-orienting movements.

Restless legs syndrome (RLS) is a neurologic disorder characterized principally by leg paresthesia and motor restlessness. Several clinical reports indicated that many patients with RLS also have arm paresthesia and restlessness. In the present study, the incidence of arm restlessness was assessed by questionnaire in 230 patients diagnosed with idiopathic RLS. Arm restlessness was reported by 48.7% of the patients. Patients with and without arm restlessness were compared with regard to clinical and polysomnographic parameters. No between-group differences were found for age at onset of RLS, duration of illness, gender, presence of a family history of RLS, sleep latency, total sleep time, sleep efficiency, and periodic leg movements index during sleep. However, arm restlessness was more frequent in patients with severe RLS. Interestingly, the polysomnographic data failed to differentiate the patients with arm restlessness from those without arm restlessness, except for sleep efficiency, which tended to be lower in patients with arm restlessness. In conclusion, the results of the present study are in agreement with clinical observations that a large proportion of patients with RLS have arm restlessness.

A high proportion of patients with restless legs syndrome (RLS) also complain of arm paresthesia but the presence of periodic arm movements (PAM) has never been documented in a sleep laboratory in these patients. We investigated the prevalence of PAM during nocturnal sleep and awakenings in 22 RLS patients. Fifteen patients had a PAM index >5 movements per hour during wakefulness and among them only 3 had a PAM index >5 during sleep. Twenty patients had a periodic leg movement (PLM) index >5 during wakefulness and 17 had a PLM index >5 during sleep. In 42.8% of cases, PAM showed temporal relationship with PLM during wakefulness. These results show that PAM is frequent in RLS and suggest that the basic neurological dysfunction responsible for RLS is probably not located exclusively at the level of the lumbar spinal cord but involves neuronal systems located at upper levels.

Simple and complex cells of visual areas of cats may be reliably classified according to the modulatory index (MI) of their responses. This investigation is aimed at analysing the MI in area 18 when a small region (about 200-400 µm in diameter) of area 17 was inactivated with a microinjection of GABA, in anesthetized cats. Cells were stimulated with sine-wave gratings whose orientation, spatial, and temporal frequencies were optimal for the studied unit. The AC and DC response components, and the MI were computed along with fast Fourier transforms of evoked discharges recorded as peristimulus time histograms. Results showed that these response components were relatively unaffected in simple cells, whereas complex cells exhibited large changes when area 17 was silenced. In particular, a large proportion of complex cells showed a MI greater than 1, thereby adopting a response pattern resembling simple cells. It is suggested that this subpopulation of complex cells receives a direct input from geniculate X cells.Key words: simple cells, complex cells, visual cortex, corticocortical influences, cats.