Motor rehabilitation therapy is commonly employed after strokes, but outcomes are variable and there is little specific information about the changes in brain activity that are associated with improved function. We performed serial functional MRI (fMRI) on a group of seven patients receiving a form of rehabilitation therapy after stroke in order to characterize functional changes in the brain that correlate with behavioural improvements. Patients were scanned while performing a hand flexion-extension movement twice before and twice after a two-week home-based therapy programme combining restraint of the unaffected limb with progressive exercises for the affected limb. As expected, the extent of improvement in hand function after therapy varied between patients. Therapy-related improvements in hand function correlated with increases in fMRI activity in the premotor cortex and secondary somatosensory cortex contralateral to the affected hand, and in superior posterior regions of the cerebellar hemispheres bilaterally (Crus I and lobule VI). fMRI offers a promising, objective approach for specifically identifying changes in brain activity potentially responsible for rehabilitation-mediated recovery of function after stroke. Our results suggest that activity changes in sensorimotor regions are associated with successful motor rehabilitation.
Background and Purpose-The mechanisms underlying motor recovery after stroke are not fully understood. Several studies used functional MRI longitudinally to relate brain activity changes with performance gains of the upper limb after therapy, but research into training-induced recovery of lower limb function has been relatively neglected thus far. Methods-We investigated functional reorganization after 4 weeks of treadmill training with partial body weight support in 18 chronic patients (mean age, 59.9Ϯ13.5 years) with mild to moderate paresis (Motricity Index affected leg: 77.7Ϯ10.5; range, 9 to 99) and gait impairment (Functional Ambulation Category: 4.4Ϯ0.6; range, 3 to 5) due to a single subcortical ischemic stroke using repeated 3.0-T functional MRI and an ankle-dorsiflexion paradigm. Results-Walking endurance improved after training (2-minute timed walking distance: 121.5Ϯ39.0 versus pre:105.1Ϯ38.1 m; Pϭ0.0001). For active movement of the paretic foot versus rest, greater walking endurance correlated with increased brain activity in the bilateral primary sensorimotor cortices, the cingulate motor areas, and the caudate nuclei bilaterally and in the thalamus of the affected hemisphere. Conclusions-Despite the strong subcortical contributions to gait control, rehabilitation-associated walking improvements are associated with cortical activation changes. This is similar to findings in upper limb rehabilitation with some differences in the involved cortical areas. We observed bihemispheric activation increases with greater recovery both in cortical and subcortical regions with movement of the paretic foot. However, although the dorsal premotor cortex appears to play an important role in recovery of hand movements, evidence for the involvement of this region in lower extremity recovery was not found.
Background and Purpose-Although knowledge concerning cortical reorganization related to upper limb function after ischemic stroke is growing, similar data for lower limb movements are limited. Previous studies with hand movement suggested increasing recruitment of motor areas in the unlesioned hemisphere with increasing disability. We used ankle movement as a lower limb analog to test for similarities and differences in recovery patterns. Methods-Eighteen subjects were selected with chronic residual gait impairment due to a single subcortical ischemic stroke. Functional MRI scans were obtained at 3.0 T during active and passive ankle dorsiflexion in the patients (8 females, 10 males; mean age, 59.9Ϯ13.5 years; range, 32 to 74 years) and 18 age-matched healthy control subjects. Results-We observed substantial neocortical activity associated with foot movement both in the patients with stroke and in the healthy control subjects. Our primary finding was increased cortical activation with increasing functional impairment. The extent of activation (particularly in the primary sensorimotor cortex and the supplementary motor area of the unlesioned hemisphere) increased with disability. The changes were most prominent with the active movement task. Conclusions-Using
We investigated the association between the degree of lesion overlap with the corticospinal tract and walking performance before and after 4-weeks of partial body weight support (PBWS) treadmill training in 18 individuals (ten male, eight female) with a mean age 59 +/- 13 years (mean +/- SD), range 32-74 years, who were ambulant and 6 months from a subcortical ischaemic stroke. Lesion volumes were manually defined on high resolution T1-weighted 3T-MRI scans and a probabilistic map of the corticospinal tract created using diffusion tensor imaging data collected previously in healthy subjects. The percentage overlap between the lesion and the corticospinal tract was calculated for each patient. Walking performance was determined by measures of 10 m speed, spatiotemporal parameters, percentage recovery of centre of mass (CoM), walking symmetry and 2-min endurance walk prior to and following 4 weeks of treadmill training with PBWS that emphasised normal fast walking. Lesion overlap measures weakly correlated with walking performance measures. Spatiotemporal and performance measures changed in response to training, but spatial symmetry and mechanical energy recovery did not. Walking speed at entry to the study predicted change in response to training of 10 m walk time and swing time asymmetry. Age and lesion overlap did not add to prediction of outcome models. The extent of lesion overlap with the corticospinal tract was not strongly associated with either walking performance or response to gait retraining, despite the correlation of these parameters with upper limb recovery.
This study shows a decrease in PIM consumption. Despite an increase of drug use in the elderly, an improving of the quality of this consumption remains possible.
Trained athletes frequently experience low levels of blood haemoglobin (13 to 14 g/100ml in men and 12 g/100ml in women) plus low haematocrit and low ferritin levels. These parameters define the concept of 'sports anaemia'. Low iron levels may be due to mechanical haemolysis, intestinal bleeding, haematuria, sweating, low iron intake or poor intestinal absorption. The resulting decrease in blood gas transport and muscle enzyme activity impairs performance. The concept of sports anaemia can be criticised. Simply measuring the blood levels does not take into account the haemodilution that occurs in athletes because of training. The lack of these measurements makes it difficult to diagnose anaemia or evaluate any treatment. Anaemia is treated by preventing decreased iron stores through a balanced food intake or iron supplements. Self-medications must be discouraged because of intolerance, risk of overdose and many other drug interactions.
RecommendationsA new objective for the European Society of Gastrointestinal Endoscopy (ESGE) is to develop long-term partnerships with African countries. For this, an International Affairs Working Group (IAWG) was formed.In conjunction with the World Endoscopy Organization (WEO), ESGE conducted a survey of gastrointestinal (GI) endoscopy in Africa.Survey results showed that many African countries have few GI endoscopy centers with adequate resources. Barriers to the development of endoscopy services include a shortage of endoscopists who have undergone advanced endoscopy training, and a lack of equipment and basic infrastructure.Diseases related to infectious etiology are more prevalent than neoplastic diseases in Africa. Any development of endoscopy services needs to consider the local prevalence of diseases for which GI endoscopy is required, as well as the availability of resources.The IAWG will initiate a cascade approach to identify and adapt ESGE guidelines for local use. The guidelines will consider the level of resources available for each intervention, as well as cost, infrastructure, and training, and will be approved by consensus of local experts who are representative of different African areas.Suitable centers in African countries will be identified, and in future will be developed into WEO/ESGE training centers, to provide local training in both basic and advanced endoscopy according to the needs of the area.
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