Neural correlates of donepezil-induced cognitive improvement in patients with right hemisphere stroke: a pilot study.

Donepezil has been proven effective in the treatment of Alzheimer's disease and vascular dementia. However, its effects on the cognitive neural network have not been fully investigated. The purpose of this study was to evaluate the effect of donepezil on reorganisation of the cognitive neural network in patients with post-stroke cognitive impairment using functional MRI (fMRI). Fourteen patients with stroke in the right hemisphere were enrolled. Participants were randomly assigned to the experimental or the control group. Donepezil (5 mg) or placebo was administered daily for four weeks. Cognitive function assessment was performed before and immediately after treatment, and repeated one month after cessation of treatment. fMRI was performed before and after treatment. Ten out of 14 patients (six in the experimental group, four in the control group) successfully completed all experimental processes. The experimental group showed significant improvements in the Mini-Mental Status Examination during the post-treatment evaluation and one-month follow-up compared to the pre-treatment evaluation (p < .05). No improvement was observed in the control group. In the experimental group fMRI showed increased activation in both prefrontal areas, both inferior frontal lobes, and in the left inferior parietal lobe. Increased recruitment of the parieto-frontal networks in the selected patients was considered to be a neural correlate of cognitive improvement induced by donepezil.

Long-term effects of rTMS on motor recovery in patients after subacute stroke.

OBJECTIVE: Repetitive transcranial magnetic stimulation (rTMS) has been recognized as a promising intervention for treatment of stroke patients. However, most previous reports have described the short-term effects of rTMS on motor performance. We conducted a sham-controlled trial to evaluate long-term effects of high-frequency rTMS on motor recovery in subacute stroke patients. METHODS: Twenty-eight patients were randomly divided into two groups, and received either real or control rTMS. Both treatments were accompanied by motor practice. A daily dose of 1000 pulses of subthreshold 10 Hz rTMS was applied over the primary motor cortex of the affected hemisphere for 10 days within one month after onset of stroke. Motor function was assessed before and after treatment, and 3 months after the stroke. RESULTS: Motor function improved in both groups after treatment; however, patients who received real rTMS experienced additional improvement in motor function of the affected upper limb. Over 3 months after the stroke, the time and type of intervention for the Motoricity Index of the affected upper extremity showed significant interaction. CONCLUSION: Positive long-term effects on motor recovery could be achieved after 10 daily sessions of high-frequency rTMS in conjunction with motor practice during the sub-acute period of stroke.

Increase in the ozone decay time in acidic ozone water and its effects on sterilization of biological warfare agents.

The sterilization properties of ozone in acidic water are investigated in this study. Acidification of water increases the ozone decay time by several times compared to the decay time in neutral water, thereby enhancing the sterilization strength of ozone in acidic water. A simple analytical model involving the viable microbial counts after contact with acidic ozone water was derived, and a sterilization experiment was conducted on bacterial cells using the acidic ozone water. The acidic ozone water was found to kill very effectively endospores of Bacillus atrophaeus ATCC 9372, thereby demonstrating the potential for disinfection of a large surface area in a very short time and for reinstating the contaminated environment as free from toxic biological agents.