Antioxidant activity of flavonoids evaluated with myoglobin method.

Antioxidant activities of four flavonoids (rutin, quercetin, luteolin, and kaempferol) and two non-flavonoids (chlorogenic acid and pyrocatechol) against four reactive oxygen species (ROS) have been measured with a myoglobin method developed by our group. The myoglobin method uses the absorbance changes of myoglobin (a probe molecule) due to the reaction with the ROS as an indicator for the antioxidant activity measurement. Myoglobin protective ratio (MPR) was defined to express the antioxidant activities of the specimens. Antioxidant activities against hypochlorite ion, hydroxyl radical, peroxyl radical, and peroxynitrite were measured with the myoglobin method. The antioxidant activities were comprehensively evaluated by plotting MPR against four ROS and vitamin C equivalent concentration evaluated by DPPH quenching method in 5-axe cobweb charts. The four flavonoids show a very similar pattern in the 5-axe cobweb charts, while the patterns of two non-flavonoids are quite different from that of the flavonoids. This procedure combining the myoglobin method with the cobweb charts is useful in the evaluation of antioxidant activities of plant-derived food, and also can be extended to monitor antioxidant condition of media for plant cell cultures.

[Dysphagia and dysarthria surgery for advanced-age myasthenia gravis].

Myasthenia gravis is often difficult to diagnose and treat in older subjects due to complications, previous history and reciprocal interaction with drugs used to treat complications. An 84-year-old woman with slowly progressive 2-year dysphagia and dysarthria had reached critical condition with aspiration pneumonia. She was diagnosed with thymoma-free myasthenia gravis and her respirator removed after being administrated an anticholinesterase drug. Her dysphagia and dysarthria did not improve. Because of severe osteoporosis with two previous lumbar compression fractures and excessive thinness, she could not be given prednisolone or immunosuppressive drugs. Following cricopharyngeal myotomy and bilateral lateral palatopharyngeal wall narrowing, she could eat without misdeglutition and speak clearly.

[Progressive dysphagia with peculiar laryngeal movement induced by tardive dystonia].

Recently, patients receiving the long-term administration of typical antipsychotics have been recognized to be at risk of developing intractable tardive dystonia. A 44-year-old man was referred to our hospital because of progressive dysphagia for about 5 years. He had received several typical antipsychotic medications since at age of 24 years for the treatment of chronic schizophrenia. The patient had been suffering from an abnormal sensation in his throat and progressive dysphagia for five years, and nasal escape on deglutition for one year. A videotape recorder esophago pharyngography revealed that his larynx was positioned low, at the level of the 6th cervical vertebra, before swallowing, and was not elevated but rather descended to the level of the 7th vertebra upon swallowing. When the larynx was in this lower position, a small amount of swallowed material was transported to the esophagus. The remaining material in the pyriform sinus overflowed into the laryngeal cavity and lower airway after swallowing. However, the patient was able to eat with ease when he was with a girl friend, eating in a restaurant, and was hungry. The peculiar downward movement of the larynx was not observed during speech production, only during deglutition. Based on these findings, we suspected that his peculiar swallowing disorder might have been induced by tardive dystonia arising from the long-term administration of typical antipsychotics.

Physiological studies of retrusive movements of the human tongue.

SUMMARY: This study identified that physiologically the superior pharyngeal constrictor muscle at the level of the base of the tongue contributes to retrusive movement of the tongue with constriction of the mid-pharyngeal cavity and possesses unique properties in terms of motor speech control along with the genioglossus muscle. From a kinematic study involving trans-nasal fiberscopy and lateral X-ray fluorography, retrusive movement of the tongue was highly correlated with constrictive movement of the mid-pharyngeal cavity. An electromyographic study revealed that the superior pharyngeal constrictor muscle at the level of the base of the tongue contributes to retrusive movement of the tongue and that the genioglossus muscle contributes to protrusive movement. We also noted that this relationship between the activities of these two muscles were in response to postural changes during vowel productions without changes in the acoustic features. These findings suggest that these two muscles act not only antagonistically to produce retrusive and protrusive movement of the tongue, but also they complement each other to conserve the shape of the vocal tract for speech production. The functional relationship between these two muscles could contribute the consecutive movement of human speech production under various conditions and might be useful when applying rehabilitation approaches for the patients with neurological speech and swallowing disorders.