Extra-large letter spacing improves reading in dyslexia

Although the causes of dyslexia are still debated, all researchers agree that the main challenge is to find ways that allow a child with dyslexia to read more words in less time, because reading more is undisputedly the most efficient intervention for dyslexia. Sophisticated training programs exist, but they typically target the component skills of reading, such as phonological awareness. After the component skills have improved, the main challenge remains (that is, reading deficits must be treated by reading more--a vicious circle for a dyslexic child). Here, we show that a simple manipulation of letter spacing substantially improved text reading performance on the fly (without any training) in a large, unselected sample of Italian and French dyslexic children. Extra-large letter spacing helps reading, because dyslexics are abnormally affected by crowding, a perceptual phenomenon with detrimental effects on letter recognition that is modulated by the spacing between letters. Extra-large letter spacing may help to break the vicious circle by rendering the reading material more easily accessible.     

Leukocyte- and endothelial-derived microparticles: a circulating source for fibrinolysis

Background

We recently assigned a new fibrinolytic function to cell-derived microparticles in vitro. In this study we explored the relevance of this novel property of microparticles to the in vivo situation.

Design and Methods

Circulating microparticles were isolated from the plasma of patients with thrombotic thrombocytopenic purpura or cardiovascular disease and from healthy subjects. Microparticles were also obtained from purified human blood cell subpopulations. The plasminogen activators on microparticles were identified by flow cytometry and enzyme-linked immunosorbent assays; their capacity to generate plasmin was quantified with a chromogenic assay and their fibrinolytic activity was determined by zymography.

Results

Circulating microparticles isolated from patients generate a range of plasmin activity at their surface. This property was related to a variable content of urokinase-type plasminogen activator and/or tissue plasminogen activator. Using distinct microparticle subpopulations, we demonstrated that plasmin is generated on endothelial and leukocyte microparticles, but not on microparticles of platelet or erythrocyte origin. Leukocyte-derived microparticles bear urokinase-type plasminogen activator and its receptor whereas endothelial microparticles carry tissue plasminogen activator and tissue plasminogen activator/inhibitor complexes.

Conclusions

Endothelial and leukocyte microparticles, bearing respectively tissue plasminogen activator or urokinase-type plasminogen activator, support a part of the fibrinolytic activity in the circulation which is modulated in pathological settings. Awareness of this blood-borne fibrinolytic activity conveyed by microparticles provides a more comprehensive view of the role of microparticles in the hemostatic equilibrium.Key words: fibrinolytic microparticles, plasmin, plasminogen, uPA, tPA     

Early detection of left ventricular systolic dysfunction using two-dimensional speckle tracking strain evaluation in healthy subjects after acute alcohol intoxication

Objectives: We evaluated the ability of two-dimensional speckle tracking strain echocardiography to detect left ventricular (LV) systolic dysfunction as compared with LV ejection fraction (EF) in healthy subjects following acute alcohol intoxication. Methods and Results: In total, 25 healthy subjects were investigated using echocardiography 4-6 hours after the onset of alcohol intoxication at a regional festive gathering, and then compared to 23 healthy control subjects without alcohol consumption. Heart rate, blood pressure, blood alcohol level, LV volumes, EF, shortening fraction, E/A ratio, as well as global longitudinal strain (LS) were recorded. Mean blood alcohol level was 1.3 ± 0.3 g.L(-1) . Mean systolic blood pressure and heart rate were slightly increased in the alcohol group compared to controls (147.5 ± 21.8 mmHg vs 127.0 ± 9.9 mmHg, P = 0.003, and 79.7 ± 10.7 bpm vs 70.6 ± 7.6 bpm, P < 0.001, respectively). While there was no significant difference in terms of LVEF (62.9 ± 4.4% vs 64.8 ± 5.9%, P = 0.18) or shortening fraction (34.7 ± 5.9% vs 36.0 ± 4.3%, P = 0.54), global LS was significantly impaired (-17.8 ± 2.0% vs -21.2 ± 1.8%, P < 0.001). In addition, subjects who consumed alcohol had increased LV end-diastolic (108.3 ± 20.1 mL vs 95.5 ± 14.6 mL, P = 0.037) and end-systolic volumes (41.6 ± 11.4 mL vs 33.7 ± 6.9 mL, P = 0.024), along with depressed aortic time-velocity integral (19.9 ± 3.2 mL vs 21.9 ± 2.5 mL, P = 0.034). According to multivariate linear regression analyses, blood alcohol level was the only factor significantly associated with global LS (β=-3.6 ± 1.0, P = 0.005). Conclusion: Alcohol intoxication around festive days induces acute LV contraction abnormalities, which may be detected using global LS by speckle tracking at an earlier stage and more accurately than LVEF decreases.     

Manual skill,hand skill asymmetry,and cognitive performances in young children

A total of 1022 children aged 3 to 6 years were examined in their preschools and 27% of them were followed up for 2 years. A computerised version of the peg‐moving task was used repeatedly to assess hand skill of the dominant and the nondominant hand. Cognitive performance was repeatedly evaluated by tasks involving speech, vocabulary, phonological memory, and visual‐spatial skills. Results showed that: (i) age, sex, and handedness effects on hand skill asymmetry generally confirmed previous reports, especially by Annett (2002); (ii) visual‐spatial and vocabulary tasks were significantly related to hand skill but speech and phonological memory tasks were not, and the role of the dominant and nondominant hand were similar; (iii) overall, manual laterality indexes were only weakly associated to some cognitive abilities; (iv) early manual skill was more strongly associated to cognitive tasks than later manual skill. These results fit the assumption of a significant role of early manual behaviour in aspects of cognitive development not relying exclusively on phonology, and raise questions about cognitive development and rehabilitation of children with early occurring manual deficiencies.