Influence of aerobic exercise training on the neural correlates of motor learning in Parkinson's disease individuals.

BACKGROUND: Aerobic exercise training (AET) has been shown to provide general health benefits, and to improve motor behaviours in particular, in individuals with Parkinson's disease (PD). However, the influence of AET on their motor learning capacities, as well as the change in neural substrates mediating this effect remains to be explored. OBJECTIVE: In the current study, we employed functional Magnetic Resonance Imaging (fMRI) to assess the effect of a 3-month AET program on the neural correlates of implicit motor sequence learning (MSL). METHODS: 20 healthy controls (HC) and 19 early PD individuals participated in a supervised, high-intensity, stationary recumbent bike training program (3 times/week for 12 weeks). Exercise prescription started at 20 min (+ 5 min/week up to 40 min) based on participant's maximal aerobic power. Before and after the AET program, participants' brain was scanned while performing an implicit version of the serial reaction time task. RESULTS: Brain data revealed pre-post MSL-related increases in functional activity in the hippocampus, striatum and cerebellum in PD patients, as well as in the striatum in HC individuals. Importantly, the functional brain changes in PD individuals correlated with changes in aerobic fitness: a positive relationship was found with increased activity in the hippocampus and striatum, while a negative relationship was observed with the cerebellar activity. CONCLUSION: Our results reveal, for the first time, that exercise training produces functional changes in known motor learning related brain structures that are consistent with improved behavioural performance observed in PD patients. As such, AET can be a valuable non-pharmacological intervention to promote, not only physical fitness in early PD, but also better motor learning capacity useful in day-to-day activities through increased plasticity in motor related structures.

Perceived environmental correlates of cycling for transport among adults in five regions of Europe.

Regular cycling for transport is an important potential contributor to daily physical activity among adults. Characteristics of the physical environment are likely to influence cycling for transport. The current study investigated associations between perceived physical environmental neighbourhood factors and adults' cycling for transport across five urban regions across Europe, and whether such associations were moderated by age, gender, education and urban region. A total of 4,612 adults from five European regions provided information about their transport-related cycling and their neighbourhood physical environmental perceptions in an online survey. Hurdle models adjusted for the clustering within neighbourhoods were performed to estimate associations between perceived physical environmental neighbourhood factors and odds of engaging in cycling for transport and minutes of cycling for transport per week. Inhabitants of neighbourhoods that were perceived to be polluted, having better street connectivity, having lower traffic speed levels and being less pleasant to walk or cycle in had higher levels of cycling for transport. Moderation analyses revealed only one interaction effect by gender. This study indicates that cycling for transport is associated with a number of perceived physical environmental neighbourhood factors across five urban regions across Europe. Our results indicated that the majority of the outcomes identified were valid for all subgroups of age, gender, education and across regions in the countries included in the study.

Enhancing both motor and cognitive functioning in Parkinson's disease: Aerobic exercise as a rehabilitative intervention.

BACKGROUND: Aerobic exercise training (AET) has been shown to provide health benefits in individuals with Parkinson's disease (PD). However, it is yet unknown to what extent AET also improves cognitive and procedural learning capacities, which ensure an optimal daily functioning. OBJECTIVE: In the current study, we assessed the effects of a 3-month AET program on executive functions (EF), implicit motor sequence learning (MSL) capacity, as well as on different health-related outcome indicators. METHODS: Twenty healthy controls (HC) and 19 early PD individuals participated in a supervised, high-intensity, stationary recumbent bike-training program (3 times/week for 12 weeks). Exercise prescription started at 20 min (+5 min/week up to 40 min) based on participant's maximal aerobic power. Before and after AET, EF tests assessed participants' inhibition and flexibility functions, whereas implicit MSL capacity was evaluated using a version of the Serial Reaction Time Task. RESULTS: The AET program was effective as indicated by significant improvement in aerobic capacity in all participants. Most importantly, AET improved inhibition but not flexibility, and motor learning skill, in both groups. CONCLUSION: Our results suggest that AET can be a valuable non-pharmacological intervention to promote physical fitness in early PD, but also better cognitive and procedural functioning.

No association between dopamine D1, D2, and D3 receptor genes and manic-depressive illness.

BACKGROUND: The dopaminergic receptor genes are candidate genes for manic-depressive illness (MDI). To test this putative involvement we used a case-control study on samples from the native population of the northwest part of France. METHODS: Fifty patients for D1 and D2, 61 patients for D3, and 86-223 controls were tested. RESULTS: No significant association was found between allelic frequencies or genotype counts and MDI, even when the data were pooled with those from published studies. CONCLUSIONS: Single mutations of either of the studied receptor genes are not major determinants of MDI.

Manic depressive illness and tyrosine hydroxylase gene: linkage heterogeneity and association.

Several studies have implicated the tyrosine hydroxylase (TH) locus within the 11p15 region in susceptibility to manic depressive illness (MDI). This possibility was further investigated by both parametric (lod score) and nonparametric (affected-pedigree-member and a case-control study) methods of analysis in 11 French MDI families and in a sample of 200 unrelated subjects. Both types of analyses corroborate the implication of this locus, and positive lod scores were obtained in two families, which most likely reflects genetic heterogeneity. Statistical analyses were also performed including available data from published reports. These analyses, which allowed for genetic heterogeneity, substantiated our findings. The combined maximum lod score for all the families studied was 3.68 at theta = 0.00 (number of families: 36) assuming heterogeneity (alpha = 15%, P = 0.01). Taken together these results converge to suggest that the risk factors for MDI lie in the 11p15 region with TH being the most likely candidate gene.

Efficiency of discography followed by chemonucleolysis in the treatment of sciatica.

One hundred and twenty-eight patients underwent discography in our department over a period of 3 years. Eighty-four of them were treated by chemonucleolysis. All the patients were punctured by a postero-lateral approach of the intervertebral disc under fluoroscopy. Although several contraindications to chemonucleolysis are known, in our study, only one case of spondylodiscitis was noted. Overall success rate was 72.6%. Twenty-three patients (27.4%) experienced similar or increased pain after treatment.

[Genetic factors of depressive risk]. / Facteurs génétiques du risque dépressif.

Since 1987, several sensational publications resulting from work performed with the new strategies of modern genetics--epidemiological genetics and molecular biology--have shed new light on the importance of genetic vulnerability factors in determining certain forms of mood disorders. The technical progress of genetics allied with the advances made in diagnosis now enable the testing of new theories on the etiopathology of thymic disorders. A considerable effort is now being made internationally and in Europe to develop the applications of molecular biology in order to clarify--at least partially--the role of genetic vulnerability factors in the etiopathology of mood disorders. In the relatively near future, standardising the methodology of linkage and association studies, and even the application of other more complex methods of analysis should lead to the nullification or confirmation of the presence of such factors on the short arm of chromosome 11 and on the long arm of the X chromosome, and should lead to the systematic detection of their presence on the entire genome. It should then be feasible to outline the genetic breakdown of mood disorders, particularly bipolar disorders, since some families seem to be linked to chromosome 11, others to X, and others, doubtless still more numerous, linked to other chromosomes. The different studies on genetic linkage performed these last four years will be presented and discussed with special emphasis on the factors which may explain the non-replication of certain studies.(ABSTRACT TRUNCATED AT 250 WORDS)