Neural substrates of cough control during coughing.

Cough is known as a protective reflex to keep the airway free from harmful substances. Although brain activity during cough was previously examined mainly by functional magnetic resonance imaging (fMRI) with model analysis, this method does not capture real brain activity during cough. To obtain accurate measurements of brain activity during cough, we conducted whole-brain scans during different coughing tasks while correcting for head motion using a restraint-free positron emission tomography (PET) system. Twenty-four healthy right-handed males underwent multiple PET scans with [15O]H2O. Four tasks were performed during scans: "resting"; "voluntary cough (VC)", which simply repeated spontaneous coughing; "induced cough (IC)", where participants coughed in response to an acid stimulus in the cough-inducing method with tartaric acid (CiTA); and "suppressed cough (SC)", where coughing was suppressed against CiTA. The whole brain analyses of motion-corrected data revealed that VC chiefly activated the cerebellum extending to pons. In contrast, CiTA-related tasks (IC and SC) activated the higher sensory regions of the cerebral cortex and associated brain regions. The present results suggest that brain activity during simple cough is controlled chiefly by infratentorial areas, whereas manipulating cough predominantly requires the higher sensory brain regions to allow top-down control of information from the periphery.

[A study of allergological examination in infants and young children at first expiratory wheezing episode].

We investigated whether, in 117 infants and young children who experienced their first episode of wheezing, abnormal findings of allergological examination is present and can predict the development of asthma. The patients showed the significantly large number of peripheral eosinophils and the significantly high serum ECP and total IgE levels, as compared to those in controls. Specific IgE antibody was also positive at a high frequency in these patients. During the follow-up period of one year and 9 months on average, the incidence of wheezing episodes were significantly higher in the patients with high levels of ECP, total IgE and specific IgE in serum than in those with normal levels of these parameters. These results suggest that it is significant to conduct allergological examination even in infants and young children, who have had wheezing episode for the first time, for the purpose of providing against the subsequent occurrence of asthma.