Structural and functional connectivity changes in response to short-term neurofeedback training with motor imagery.

Recent findings have been challenging current understanding of how fast the human brain change its structural and functional connections in response to training. One powerful way to deepen the inner workings of human brain plasticity is using neurofeedback (NFB) by fMRI, a technique that allows self-induced brain plasticity by means of modulating brain activity in real time. In the present randomized, double-blind and sham-controlled study, we use NFB to train healthy individuals to reinforce brain patterns related to motor execution while performing a motor imagery task, with no overt movement. After 1 h of NFB training, participants displayed increased fractional anisotropy (FA) in the sensorimotor segment of corpus callosum and increased functional connectivity of the sensorimotor resting state network. Increased functional connectivity was also observed in the default mode network. These results were not observed in the control group, which was trained with sham feedback. To our knowledge, this is the first demonstration of white matter FA changes following a very short training schedule (<1 h). Our results suggest that NFB by fMRI can be an interesting tool to explore dynamic aspects of brain plasticity and open new venues for investigating brain plasticity in healthy individuals and in neurological conditions.

Beneficial effects of coronary venous retroinfusion of superoxide dismutase and catalase on reperfusion arrhythmias, myocardial function, and infarct size in dogs.

The efficacy of coronary venous retroinfusion of superoxide dismutase and catalase was studied in anesthetized closed chest dogs with 90-min left anterior descending coronary artery (LAD) occlusion followed by 3-h reperfusion. In group A, superoxide dismutase (2.5 mg/kg) and catalase (2.5 mg/kg) were administered by a 30-min continuous right atrial infusion beginning 15 min before reperfusion and supplemented by a bolus injection of superoxide dismutase (2.5 mg/kg) and catalase (2.5 mg/kg) through the great cardiac vein immediately before reperfusion. The treatment in group B was similar to that in group A, except that the bolus injection was into the right atrium. In the control group (group C), saline was administered in the same manner as in group A. Infarct size, expressed as a percentage of the risk area, was significantly smaller in group A (11.3 +/- 8.9%) than in groups B (31.3 +/- 21.1%) and C (43.0 +/- 16.9%; p less than 0.05). Regional function of the ischemic zone measured by two-dimensional echocardiography exhibited significantly (p less than 0.05) greater recovery after 3-h reperfusion in group A (30.3 +/- 8.4%) versus groups B (12.5 +/- 13.7%) and C (12.1 +/- 11.7%). Moreover, there were significantly fewer postreperfusion ventricular arrhythmias in group A as compared with groups B and C. The results of this study indicate that coronary venous retroinfusion is an effective method for delivery of superoxide dismutase and catalase.

Differentiation between psoriatic arthritis and rheumatoid arthritis: a biochemical and statistical analysis of fingernail amino acids.

The differentiation between psoriatic arthritis and rheumatoid arthritis can be clinically difficult if there is no manifest psoriasis of skin or nail. In order to clarify this diagnostic problem, the amino acid patterns in seventy-five psoriatic and non-psoriatic nails have been studied. Using gas--liquid chromatographic techniques and discriminant analysis, a high degree of differentiation (96%) has been established between the normal looking nails of patients with psoriatic arthritis and those with rheumatoid arthritis. This biochemical/statistical approach to the fingernail enhances diagnosis in difficult clinical problems, particularly where there are no overt manifestations of psoriasis.