The time course of changes in motor evoked potentials (MEPs) from the right first dorsal interosseous muscles (FDI) elicited by transcranial magnetic stimulation (TMS) influenced by cutaneous digital nerve electrical stimulation in the right index finger was investigated. Eight subjects from a total of eighteen normal subjects enrolled in the study volunteered for the experiments. The electrical stimulation was delivered at twice the sensory threshold. TMS was delivered at 1/7Hz and adjusted to a stimulator output of between 5% and 20% above the resting motor threshold of the right FDI so that the amplitudes of unconditioned MEPs without digital nerve stimulation were less than 1mV. Significant facilitation of the conditioned MEP size was observed at the mean values of 20ms and 50-80ms. Subsequently, using repetitive dual stimulation consisting of digital nerve stimulation and TMS with 70ms delay, the long lasting excitability of corticospinal tracts was also investigated. Twelve subjects from the total eighteen normal subjects enrolled in the study volunteered for the experiments. Following 30min of 0.1Hz dual stimulation, MEPs were significantly increased in amplitude, silent periods were significantly prolonged, but F-waves were not increased in amplitude. In conclusion, the immediate effects observed around 50-80ms after peripheral sensory input and the long lasting effects after prolonged dual stimulation appeared to be transcortical.

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Latex, a natural material derived from the rubber tree, is reported to cause a wide spectrum of allergic symptoms ranging from mild rhinitis to severe anaphylaxis. Individuals who frequently come into contact with latex are at risk of latex hypersensitivity. Furthermore, patients with latex hypersensitivity have cross-reactions to various foods, especially fruits, a condition which is called latex fruit syndrome. With the use of latex products becoming widespread, latex allergies are an increasingly common occurance. Although patients with spinal cord injury (SCI) are frequently exposed to latex products in daily living, i. e., bladder catheterization and manual defecation, reports concerning the significance of latex fruit syndrome are scarce. We reported a case with latex fruit syndrome in a 56-year-old tetraplegic patient who developed an allergic reaction to bananas and corn during hospitalization. In this case, the patient had cross-reactivity to latex and many different kinds of foods. The specific IgE RAST was positive to latex, avocado, banana, apple and buckwheat, and false positive to corn, kiwi, tomato, spinach and carrot. After avoiding those foods that have cross-reactions to latex proteins, his allergic reactions ceased. The significance of latex fruit syndrome in the SCI population is not recognized among medical staff, the patients themselves or their families. Patients who are exposed to latex products should be advised to take extra precautions against latex fruit syndrome and to use non-latex products as soon as this syndrome manifest itself so as to prevent further sensitization to latex proteins.

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Many individuals in Japan have suffered from so-called post-polio syndrome (PPS) since the early 1980s, because poliomyelitis epidemics occurred in Japan up to the late 1950s. PPS is defined as the development of new weakness and fatigue in the skeletal or bulbar muscles arising from an unknown cause at 25-30 years after an acute attack of paralytic poliomyelitis. PPS is hypothesized to arise when the remaining motor neurons in the post-polio state can no longer maintain all of their distal axonal sprouts. Electrophysiological studies have confirmed the presence of ongoing denervation and chronic reinnervation. The symptoms and signs of PPS include new muscle weakness and atrophy (post-poliomyelitis progressive muscular atrophy; PPMA), as well as other musculoskeletal symptoms such as fatigue, skeletal deformity, and pain. Psychological problems may also modify the other symptoms. Weight control, avoiding overwork, proper posture and alignment, lifestyle modification and the use of orthoses or other devices are helpful for the management of PPS. In addition, muscle strengthening and aerobic exercises have been reported to be useful even in PPS patients with a current exercise regimen. Exercise should be based on the status of each limb and the regimen should be modified if any new weakness, pain, or fatigue appears.

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