Plasma diamine oxidase activity in asthmatic children

Histamine plays an important role in the development of asthmatic symptoms. Diamine oxidase (DAO histaminase), which inactivates histamine, is located in the intestine and kidney and is released into plasma. Plasma DAO activity in asthmatic children was measured by a recently developed high performance liquid chromatographic method using histamine as the DAO substrate. Diamine oxidase activity was higher in severely asthmatic children than in those with mild asthma. A time course study during the acute exacerbation phase revealed that DAO activity rose during acute asthmatic attacks and then decreased gradually over several days. Although the mechanisms of plasma DAO activity increase during acute asthmatic attacks could not be explained, data showed that plasma DAO activity is an important index of histamine metabolism in asthmatics and may relate to some mechanisms of acute exacerbation of airway inflammation. Consequently, fluctuations in plasma DAO can be used as one of various indices of instability in management of asthma

Summary of the

The possible existence of deeply-bound $\bar K$-nuclear bound states, kaonic nuclei, has been widely discussed as products of the strongly attractive $\bar K$N interaction in I = 0 channels. Investigations of those exotic states will provide us unique information of the $\bar K$N interaction below the threshold, which is still not fully understood so far. Recently, we observed the simplest kaonic nuclei, $\bar K$NN, having a much deeper binding energy than normal nuclei via inflight (K−, N) reactions at the J-PARC E15 experiment. For further studies, we have proposed a series of experimental programs for the systematic investigation of light kaonic nuclei, from $\bar K$N (Λ(1405)) to $\bar K$NNNN. We will measure the $\bar K$NNN (A = 3) system at the new experiment approved as J-PARC E80, as a first step toward a comprehensive study