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Purpose: The ipsilateral hand (ILH) is impaired after unilateral stroke, but the underlying mechanisms remain unresolved. Based on the degeneracy theory of network connectivity that many connectivity patterns are functionally equivalent, we hypothesized that ILH impairment would result from the summation of microstructural white matter (WM) disruption in the motor network, with a task-related profile. We aimed to determine the WM disruption patterns associated with ILH impairment., Methods: This was a cross-sectional analysis of patients in the ISIS-HERMES Study with ILH and diffusion-MRI data collected 1 month post-stroke. Patients performed three tasks, the Purdue Pegboard Test (PPT), handgrip strength, and movement time. Fractional anisotropy (FA) derived from diffusion MRI was measured in 33 WM regions. We used linear regression models controlling for age, sex, and education to determine WM regions associated with ILH impairment., Results: PPT was impaired in 42%, grip in 59%, and movement time in 24% of 29 included patients (mean age, 51.9 ± 10.5 years; 21 men). PPT was predicted by ipsilesional corticospinal tract (i-CST) (B = 17.95; p = 0.002) and superior longitudinal Fasciculus (i-SLF) (B = 20.52; p = 0.008); handgrip by i-CST (B = 109.58; p = 0.016) and contralesional anterior corona radiata (B = 42.69; p = 0.039); and movement time by the corpus callosum (B =  - 1810.03; p = 0.003) i-SLF (B =  - 917.45; p = 0.015), contralesional pons-CST (B = 1744.31; p = 0.016), and i-corticoreticulospinal pathway (B =  - 380.54; p = 0.037)., Conclusion: ILH impairment was associated with WM disruption to a combination of ipsilateral and contralesional tracts with a pattern influenced by task-related processes, supporting the degeneracy theory. We propose to integrate ILH assessment in rehabilitation programs and treatment interventions such as neuromodulation., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Ipsilateral hand (ILH) impairment is documented following motor stroke, but its impact on long-term outcome remains unknown. We assessed ILH impairment in subacute stroke and tested whether ILH impairment predicted long-term outcome., Methods: We performed a longitudinal study in 209 consecutive patients with unilateral stroke and sensorimotor deficit at admission. ILH impairment was evaluated using the Purdue Pegboard Test (PPT) and handgrip strength and defined as mild (z-score < -1) or moderate (z-score < -1.65). We used logistic regression (LR) to predict outcome assessed 9 (range, 7-12) months post-stroke with the modified Rankin scale (mRS) categorized into good (mRS ≤ 1) and poor outcome (mRS ≥ 2). For internal validation, LR-bootstrapping and cross-validation with LASSO and Random Forest were performed., Results: ILH impairment assessed at 89.04 ± 45.82 days post-stroke was moderate in 10.53% (95% CI 6.7, 14.83) for PPT and 17.22% (95% CI 11.96, 22.49) for grip, and mild in 21.05% (95% CI 15.78, 26.79) for PPT and 35.89 (95% CI 29.67, 42.58) for grip. Good outcome was predicted by ILH-PPT (B = 1.03 [95% CI 0.39, 3.31]), ILH-grip (B = 1.16 [95% CI 0.54, 3.53]), low NIHSS-discharge (B = -1.57 [95% CI -4.0, -1.19]), and no depression (B = -0.62 [95% CI -1.63, -0.43]), accounting for stroke delay (B = -0.011 [95% CI -0.06, 0.01]). Model efficiency was 91.6% (AUC = 0.977; 95% CI 0.959, 0.996). LASSO and Random Forest methods provided similar results, confirming the LR model robustness., Conclusions: ILH impairment is frequent after motor stroke and predicts long-term outcome. We propose to integrate ILH impairment into rehabilitation programs to improve recovery and serve research interventions such as neuromodulation., (© 2022 European Academy of Neurology.)

Motor hand deficits impact autonomy in everyday life, and neuroplasticity processes of motor recovery can be explored using functional MRI (fMRI). However, few studies have used fMRI to explore the mechanisms underlying hand recovery following stroke. Based on the dual visuomotor model positing that two segregated dorsomedial and dorsolateral cerebral networks control reach and grasp movements, we explored the relationship between motor task-related activity in the sensorimotor network and hand recovery following stroke. Behavioral recovery was explored with a handgrip force task assessing simple grasp, and a visuomotor reaching and precise grasping task, the Purdue Pegboard Test (PPT). We used a passive wrist flexion-extension task to measure fMRI activity in 36 sensorimotor brain areas. Behavioral and fMRI measurements were performed in 27 patients (53.2 ± 9.5 years) 1-month following stroke, and then 6-month and 24-month later. The effects of sensorimotor activity on hand recovery were analyzed using correlations and linear mixed models (LMMs). PPT and handgrip force correlated with fMRI activity measures in the sensorimotor and parietal areas. PPT recovery was modeled by fMRI measures in the ipsilesional primary motor cortex (MI-4p), superior parietal lobule (SPL-7M) and parietal operculum OP1, and lesion side. Handgrip force was modeled by ipsilesional MI-4a, OP1, and contralesional inferior parietal lobule (IPL-PFt). Moreover, the relationship between fMRI activity and hand recovery was time-dependent, occurring in the early recovery period in SPL-BA-7M, and later in MI. These results suggest that areas of both dorsolateral and dorsomedial networks participate to visuomotor reach and grasp tasks (PPT), while dorsolateral network areas may control recovery of simple grasp (handgrip force), suggesting that the type of movement modulates network recruitment. We also found functional dissociations between MI-4p related to PPT that required independent finger movements and MI-4a related to simple grasp without independent finger movements. These findings need to be replicated in further studies., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Stroke is the leading cause of disability in adults. Many current clinical trials use intravenous (IV) administration of human bone marrow-derived mesenchymal stem cells (BM-MSCs). This autologous graft requires a delay for ex vivo expansion of cells. We followed microvascular effects and mechanisms of action involved after an IV injection of human BM-MSCs (hBM-MSCs) at a subacute phase of stroke. Rats underwent a transient middle cerebral artery occlusion (MCAo) or a surgery without occlusion (sham) at day 0 (D0). At D8, rats received an IV injection of 3 million hBM-MSCs or PBS-glutamine. In a longitudinal behavioral follow-up, we showed delayed somatosensory and cognitive benefits 4 to 7 weeks after hBM-MSC injection. In a separate longitudinal in vivo magnetic resonance imaging (MRI) study, we observed an enhanced vascular density in the ischemic area 2 and 3 weeks after hBM-MSC injection. Histology and quantitative polymerase chain reaction (qPCR) revealed an overexpression of angiogenic factors such as Ang1 and transforming growth factor-1 (TGF-1) at D16 in hBM-MSC-treated MCAo rats compared to PBS-treated MCAo rats. Altogether, delayed IV injection of hBM-MSCs provides functional benefits and increases cerebral angiogenesis in the stroke lesion via a release of endogenous angiogenic factors enhancing the stabilization of newborn vessels. Enhanced angiogenesis could therefore be a means of improving functional recovery after stroke.

Objective: The treatment of proximal located scaphoid nonunion is a well-known and common problem. For these patients, we used a vascular pedicled bone graft of the distal radius., Methods: In the last 7 years, 75 patients were treated with the vascular pedicled bone graft. Retrospectively, patients' data, healing rates, and factors influencing scaphoid healing were analyzed., Results: The overall healing rate in cases with proximal located nonunions (n = 54) was approximately 70%. Out of these 54 patients, 47 patients showed avascular proximal fragments. Multivariate analysis showed no significant impact for the factors age, smoking, duration of disease, or previous operation., Conclusions: In our negative selected patient group, we were able to achieve good results with the usage of a pedicled vascularized bone graft of the distal radius. Our results indicate a favorable outcome for the use of a pedicled vascularized distal radius bone graft in both scaphoid nonunion fractures of the proximal third, with or without an avascular proximal pole.

Background: Microvasculature plays a key role in stroke pathophysiology both during initial damage and extended neural repair. Moreover, angiogenesis processes seem to be a promising target for future neurorestorative therapies. However, dynamic changes of microvessels after stroke still remain unclear, and MRI follow-up could be interesting as an in vivo biomarker of these., Methods: The aim of this study is to characterize the microvascular plasticity 25 days after ischemic stroke using both in vivo microvascular 7T-MRI (vascular permeability, cerebral blood volume (CBV), vessel size index (VSI), vascular density) and quantification of angiogenic factor expressions by RT-qPCR in a transient middle cerebral artery occlusion rat model. CBV and VSI (perfused vessel caliber) imaging was performed using a steady-state approach with a multi gradient-echo spin-echo sequence before and 2 min after intravenous (IV) injection of ultrasmall superparamagnetic iron particles. Vascular density (per mm2) was derived from the ratio [ΔR₂/(ΔR₂*)²/³]. Blood brain barrier leakage was assessed using T₁W images before and after IV injection of Gd-DOTA. Additionally, microvessel immunohistology was done., Results: 3 successive stages were observed: 1) 'Acute stage' from day 1 to day 3 post-stroke (D1-D3) characterized by high levels of angiopoietin-2 (Ang2), vascular endothelial growth factor receptor-2 (VEGFR-2) and endothelial NO synthase (eNOS) that may be associated with deleterious vascular permeability and vasodilation; 2) 'Transition stage' (D3-D7) that involves transforming the growth factors β1 (TGFβ1), Ang1, and tyrosine kinase with immunoglobulin-like and endothelial growth factor-like domains 1 (Tie1), stromal-derived factor-1 (SDF-1), chemokine receptor type 4 (CXCR-4); and 3) 'Subacute stage' (D7-D25) with high levels of Ang1, Ang2, VEGF, VEGFR-1 and TGFβ1 leading to favorable stabilization and maturation of microvessels. In vivo MRI appeared in line with the angiogenic factors changes with a delay of at least 1 day. All MRI parameters varied over time, revealing the different aspects of the post-stroke microvascular plasticity. At D25, despite a normal CBV, MRI revealed a limited microvessel density, which is insufficient to support a good neural repair., Conclusions: Microvasculature MRI can provide imaging of different states of functional (perfused) microvessels after stroke. These results highlight that multiparametric MRI is useful to assess post-stroke angiogenesis, and could be used as a biomarker notably for neurorestorative therapy studies. Additionally, we identified that endogenous vessel maturation and stabilization occur during the 'subacute stage'. Thus, pro-angiogenic treatments, such as cell-based therapy, would be relevant during this subacute phase of stroke.

The OSLER test represents a simple alternative to the maintenance of wakefulness test. Standard analysis of OSLER test results yields a mean sleep latency (MSL). The aim of this study was to use both MSL and errors (nonresponses to stimulations) to characterize daytime sleepiness in apneic patients. OSLER test results at 9:00 A.M., 11:00 A.M. and 1:30 P.M. were compared in 27 obstructive sleep apnea syndrome patients (50.4 +/- 10.4 years; apnea-hypopnea index: 43.05 +/- 25.08) and 20 control subjects (C). Not only did obstructive sleep apnea syndrome patients demonstrate earlier sleep onset than control subjects (MSL: 1,788 seconds +/- 511 versus 2,335 seconds +/- 139, p < 0.001), but they also spent a greater percentage of time making errors than control subjects (5.4% +/- 4.7 of total test time versus 0.4% +/- 0.4, p < 0.001) with specific error profiles (high prevalence of three to six consecutive errors). When error profile analysis was added to standard sleep latency assessment, up to 40% of patients with normal sleep latency were exhibiting abnormal fluctuation in vigilance. A single 9:00 A.M. OSLER session appeared as sensitive as three consecutive sessions in its use as a means of identifying patients with significant daytime sleepiness. On the other hand, the 1:30 P.M. OSLER test session was least specific to distinguish apneic subjects from normal subjects, suggesting that the OSLER test can identify the afternoon peak in physiologic somnolence.

Several lines of evidence seem to indicate that some neurocognitive measures could be phenotypic markers of predisposition to schizophrenia. The aim of this study was to investigate 21 patients with schizophrenia, 51 of their first-degree relatives and 46 nonpsychiatric controls, with a series of tests known to be sensitive to prefrontal cortical damage--the Trail Making Test, part B (TMT B), the Wisconsin Card Sorting Test (WCST) and a verbal fluency test (VFT)- and/or sensitive to temporo-hippocampic dysfunctions: verbal and visual memory and verbal learning tests from the Wechsler Memory Scale-Revised (Wechsler, 1987). Since parents and siblings share on average 50% of their genes with the schizophrenic proband, firstly we predicted that the first-degree relatives' performance would be at an intermediate level between patients and control subjects and secondly, we expected that a higher proportion of relatives than of control subjects would be impaired. The patients demonstrated deviant patterns of neuropsychological performance on the three tests sensitive to frontal dysfunctions and on most of the memory and learning tests. In the relative group, performance on the TMT B, VFT, immediate verbal recall and verbal learning was at an intermediate level between both other groups and significantly impaired compared to control subjects. However, the relative group did not differ from the control group on the WCST, immediate visual recall, and delayed verbal and visual recalls. Furthermore, compared to the control group, the percentages of patients and relatives who scored one standard deviation below the mean control group were significantly higher for the VFT and immediate verbal recall scores. Among all the tests studied, the verbal fluency and the immediate verbal recall appeared to be valuable phenotypic markers of schizophrenia since: (i) their mean scores were poorer in the patient and in the relative groups, (ii) the percentages of patients and relatives with poor performance were higher than the percentage of controls, (iii) these deficits were not due to poorer general intellectual abilities in the relative group, (iv) these deficits did not correlate with anxiety or depression scores.

Cognitive impairments in Parkinson's disease (PD) could be explained by a central executive (CE) deficit in A. D. Baddeley's (1986) working memory model. To test this hypothesis, verbal, spatial, and double span tasks were given to 12 medicated PD patients and control participants, with varying recall delays. The double span task was assigned to explore the coordinating and integrating function of the CE, and lengthening the recall delay was expected to implicate more attentional resources. PD patients had lower spans relative to controls in all tasks. However, the more specific implication of the CE was difficult to prove. One reason could be that PD patients were on dopaminergic treatment when tested. To control this effect, 12 PD patients on and off medication were studied in a second experiment using the same tasks. PD patients off medication had lower spans only in the double task; this result underlines the role of dopamine on working memory processes.

The impairment in tasks requiring intact frontal lobe functions has been repeatedly shown in schizophrenics. However, the relative roles of confounding factors, like duration of the disease, social withdrawal, or antidopaminergic medication, are not clearly demonstrated. We studied the performance of 12 young active patients, with chronic residual schizophrenia that had recent onset, and 12 control subjects, with frontal lobe tests and with a battery designed to explore working memory. The results show normal performance in schizophrenia. The small number of patients does not allow definitive conclusions, but this study suggests that a frontal dysfunction may not be present early in the evolution of schizophrenia in active patients.

A dysfunction of dorsolateral prefrontal cortex (DLPF) in major depression is suggested by functional imagery and comparative neuropsychology. However, assessment of frontal lobe syndrome with DLPF-dependent tests led to controversial results. To clarify these findings, we administered 5 of these tests (Wisconsin Card Sorting Test, Stroop Test, Trail Making Test, Tower of Toronto, verbal fluency) to 16 major depressive subjects and their 16 controls, before and after 21 days of treatment. Furthermore, we tried to assess the prognostic value of frontal lobe dysfunction, and its relation with the endogenous or exogenous nature of the depression on the one hand, the severity of the depression on the other hand. Our results suggest that the presence of a frontal lobe syndrome (defined by impaired performances at 3 tests or more) is only noted in endogenous depression; after treatment, no impairment is detected. No correlation is found with the severity of the depression. Frontal lobe syndrome does not seem to indicate poorer prognosis for current depressive episode.

At the first International Conference for Health Promotion, Canada presented "Achieving Health for All: A Framework for Health Promotion". This document reflects current thinking and proposes a conceptual base for the analysis of contemporary and emerging health issues. The approach is founded on the principles of health promotion developed by the World Health Organization and assimilates the themes which subsequently emerged in the Ottawa Charter. As such, Canada's framework presents a context for discussing chronic illnesses and for identifying opportunities that will lead to an intersectoral course of action. The salient features of this framework (Fig. 1) are briefly discussed.

Twenty-two patients who underwent surgery for ruptured aneurysm of the anterior communicating artery were investigated by a battery of neuropsychological tests, including memory evaluation tests. According to the results obtained at these tests the patients were divided into three groups: 1) 7 patients had no memory disorders; 2) 10 patients presented with memory disorders affecting memory; their complaints concerned behavior, and the memory deficit was discovered at neuropsychological examination; 3) 5 patients presented with an obvious amnesic syndrome, and the tests confirmed a severe learning deficit and a severe forgetting while recognition remained normal in 4 patients. Age, residual lesions at CT and electrophysiological signs of focalization correlated well with the residual neuropsychological disorders. Leaving aside quantitative aspects, the memory deficits observed in the second and third groups seemed to be qualitatively different and might correspond to different anatomical and functional sequelae.