Objectives: To analyze writing patterns in patients with writer's cramp using a simple pen-type writing pressure gauge. Design: Paired comparisons of writing parameters between patients with writer's cramp and the controls. Setting: Outpatient clinic in the department of rehabilitation medicine of a university hospital in Japan. Subjects: 10 healthy subjects (average age, 32.7 years; 6 males) and 10 patients with writer's cramp (average age, 47.6 years; 9 males). Main outcome measures: Maximum and average writing pressure; the degree of variation in writing pressure, which reflects the writer's skill in writing; and writing time, which is the amount of time required to complete the task. Results: The intra-class correlations were over 0.7 for all parameters in the healthy subjects, indicating satisfactory reproducibility. Writing time and degrees of variation in patients with writer's cramp were significantly longer and larger, respectively, than those in the controls. Conclusions: The electronic pen is an easily used instrument and is useful for reliable analysis of writing patterns. Writing time and degree of variation are recommended as reliable parameters for characterizing patients with writer's cramp.

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We established the long lasting effects of motor point stimulation paired with repetitive transcranial magnetic stimulation (rTMS) over the motor cortex in persons with hemiparetic stroke. In six subjects, 0.1Hz rTMS over the contralateral hand area of the primary motor cortex (MIHAND) paired with motor point stimulation of the affected abductor pollicis brevis (APB) muscle was applied for 30min. The motor evoked potentials (MEPs) in the affected first dorsal interosseous (FDI) muscle increased in amplitude immediately after conditioning and recovered to baseline after 30 minutes, whilst F wave by ulnar nerve stimulation at the wrist showed little change in amplitude. In hemiparetic stroke patients, as well as in healthy subjects, paired stimulation increases the excitability of the motor cortex for short periods after stimulation. This finding might have potential therapeutic implications for stroke rehabilitation.

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The purpose of this report is to classify healthy subjects' upper esophageal imaging patterns using videofluoroscopic examination in the anterior-posterior planes. There were 109 subjects who swallowed 5ml of 40% barium solution 3 times each, for a total of 327 swallows evaluated. By laterality of the right under pyriform sinus flow, the large classification of the imaging patterns was performed as follows: only left (right) side pyriform sinus flow, dominant left (right) side pyriform sinus flow, and both sides pyriform sinus flow. The pattern was segmented from the existence of the confluence in the upper esophagus, and 13 kinds of imaging patterns were defined. Sixty-percent of the subjects were classified with bilateral pyriform sinus passages, while 40% of the subjects were classified into a group showing laterality. When there was laterality, the left side was often the side of dominant flow. Some reasons for why laterality may occur are considered. Differences of the inflow to the hypopharynx can cause laterality of the sensory input, which may produce laterality of the hypopharynx contraction pressure and pharyngoesophageal segment opening. Another reason may be that the anatomical position of the upper esophagus runs a little to the left of the median line. However, it is necessary to carry out further research into the anatomical and functional reasons.

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Muscle hyperplasia, an increase in the number of muscle fibers, occurs as a result of two mechanisms related to satellite cells. One mechanism is a splitting or branching of muscle fibers, and the other is a new formation of muscle fibers. Skeletal muscle hypertrophy generally occurs due to hypertrophy of muscle fibers themselves, but it remains controversial as to whether or not it is actually associated with hyperplasia. To prove hyperplasia, measurement of the number of muscle fibers is necessary. Two methods are available for making such a measurement: a direct method which counts all muscle fibers in a sample of muscle, and an indirect method which estimates all muscle fibers from several biopsy specimens and the relative cross sectional area of the muscle biopsy site. Both methods have their own limitations. In general, the number of muscle fibers is measured with a direct method in animals and with an indirect method in humans. Several reports have shown an increase in the number muscle fibers in animals under isotonic, high load and short duration exercises. Muscle regeneration after muscle injuries incurred during exercises are considered as a factor in hyperplasia induced by exercise. Such regeneration has mainly been evaluated as satellite cell activity, and several reports have demonstrated that this type of regeneration can be promoted by growth factors, ultrasound, and muscle stretching. There remains a need to investigate the effect of various promoters and exercises on hyperplasia, and we expect to clinically apply the results obtained with these basic studies.

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