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Notes: Summary Rhizotomy of the dorsal roots of the upper limb in lesioned monkeys with lesioned-induced and harmaline-induced tremor caused complete anaesthesia and akinesia of the corresponding limb, which only showed purposeless movements. The rate and rhythm of postural tremor and the reciprocality of the bursts in opposite muscles were not affected by the rhizotomy; the incidence of tremor episodes was greater in some animals. Rhizotomy apparently interfered with the amplitude of the bursts which, at times, was less regular in the deafferented limb. In four out of six animals the rhizotomy involved the blood supply of the dorsal part of the lateral column. This caused a degeneration of the corresponding lateral corticospinal and dorsal spinocerebellar tracts, producing a weakness of the ipsilateral lower limb which gradually improved. Faster bursts (12–13/sec) were also noted on the EMG in response to harmaline in monkeys with cerebellar lesions. These findings suggest that the influence transmitted through the spinal dorsal roots does not play an important role in initiating postural tremor. The rate and rhythm of tremor episodes are uninfluenced by impulses transmitted through the dorsal roots which, however, apparently exert a stabilizing effect on the amplitude of the bursts.

Notes: Using an antibody that recognizes the products of all known members of the fos family of immediate early genes, it was demonstrated that destruction of the nigrostriatal pathway by 6-hydroxydopamine (6-OHDA) lesions of the medial forebrain bundle produces a prolonged (〉3 months) elevation of Fos-like immunoreactivity in the striatum. Using retrograde tract tracing techniques, we have previously shown that this increase in Foslike immunoreactivity is located predominantly in striatal neurons that project to the globus pallidus. In the present study, Western blots were performed on nuclear extracts from the intact and denervated striatum of 6-OHDA-lesioned rats to determine the nature of Fos-immunoreactive protein(s) responsible for this increase. Approximately 6 weeks after the 6-OHDA lesion, expression of two Fos-related antigens with apparent molecular masses of 43 and 45 kDa was enhanced in the denervated striatum. Chronic haloperidol administration also selectively elevated expression of these Fos-related antigens, suggesting that their induction after dopaminergic denervation is mediated by reduced activation of D2-like dopamine receptors. Western blot immunostaining using an antibody which recognizes the N-terminus of FosB indicated that the 43 and 45 kDa Fos-related antigens induced by dopaminergic denervation and chronic haloperidol administration may be related to a truncated from of FosB known as ΔFosB. Consistent with this proposal, retrograde tracing experiments confirmed that ΔFosB-like immunoreactivity in the deafferented striatum was located predominantly in striatopallidal neurons. Gel shift experiments demonstrated that elevated AP-1 binding activity in denervated striata contained FosB-like protein(s), suggesting that enhanced ΔFosB levels may mediate some of the effects of prolonged dopamine depletion on AP-1-regulated genes in striatopallidal neurons. In contrast, chronic administration of the D1-like receptor agonist CY 208–243 to 6-OHDA-lesioned rats dramatically enhanced ΔFosB-like immunoreactivity in striatal neurons projecting to the substantia nigra. Western blot immunostaining revealed that ΔFosB and, to a lesser extent, FosB are elevated by chronic D1-like agonist administration. Both the quantitative reverse transcriptase-polymerase chain reaction and the ribonuclease protection assay demonstrated that Δfos B mRNA levels were substantially enhanced in the denervated striatum by chronic D1-like agonist administration. Lastly, we examined the effects of chronic administration of D1-like and D2-like dopamine receptor agonists on striatal ΔFosB expression in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) primate model of Parkinson's disease. In monkeys rendered Parkinsonian by MPTP, there was a modest increase in ΔFosB-like protein(s), while the development of dyskinesia produced by chronic D1-like agonist administration was accompanied by large increases in ΔFosB-like protein(s). In contrast, administration of the long-acting D2-like agonist cabergoline, which alleviated Parkinsonian symptoms without producing dyskinesia reduced ΔFosB levels to near normal. Taken together, these results demonstrate that chronic alterations in dopaminergic neurotransmission produce a persistent elevation of ΔFosB-like protein(s) in both the rodent and primate striatum.

Notes: Background and objectives The determinants of variability in the clinical expression of atopy are still to be documented. The goals of this study were to determine, in subjects with a clinical diagnosis of symptomatic asthma or rhinitis, what is the possible contribution of different types of indoor and outdoor allergens to the development of their disease, by looking at the prevalence and degree of sensitization to these allergens according to age and gender.Subjects and methods We analysed allergy skin prick tests to common airborne indoor and outdoor allergens in 3371 consecutive patients, grouped according to diagnosis of allergic asthma, rhinitis, or both. For each of these three groups, we calculated the prevalence of sensitization to indoor/outdoor allergens, the atopic index (Al), the number of positive responses to allergy skin prick test and the mean wheal diameter (MWD) of these responses.Results The prevalence of atopy and the values of Al and MWD peaked in subjects aged 16 to 25 years, declining afterwards; in subjects ± 18 years old, atopic indices were slightly higher in men than in women. In atopic subjects, the prevalence of sensitization was, in decreasing order: housedust (84.2%), cat hair-epithelium (76.5%), dog hair-dander (63.0%), house dust mite (54.2%), grasses (51.9%), trees (47.2%) and ragweed pollens (44.9%) and finally, moulds (25.4%). Among subjects sensitized only to outdoor allergens (n= 195), 73.8% had a rhinitis, 11.8% had asthma and 14.4% had both diagnoses; for those sensitized only to indoor allergens (n= 710), these values were respeetively 48.6, 24.5 and 26.9%, and for those sensitized to both indoor and outdoor allergens (n= 1793), the comparable values were 55.5, 14.6 and 29.9%.Conclusion These data show that in our population of subjects with respiratory allergic symptoms, indoor allergen sensitization is strongly associated with asthma, while exclusive sensitization to pollens is associated primarily with rhinitis. Sensitization was more prevalent for indoor allergens than for outdoor allergens in all groups determined according to diagnosis or age. Indices of atopy were higher in men in the group ± 18 years old. Prevalence and degree of sensitization were shown to peak in young adults, regardless of the allergen, and to diminish with age. This study stresses the role of indoor allergens in the development of asthma and shows the variability of allergic manifestations according to the type of sensitization.