The elevation of p53 protein level and SOD activity in the resident blood of the Misasa radon hot spring district

To clarify the mechanism by which radon hot springs prevent cancer or not, in this study, blood was collected from residents in the Misasa hot spring district and in a control district. The level of a representative cancer-suppressive gene, p53, and the activity of a representative antioxidant enzyme, superoxide dismutase (SOD), were analyzed as indices. The level of serum p53 protein in the males in the Misasa hot spring district was found to be 2-fold higher than that in the control district, which is a significant difference. In the females in the Misasa hot spring district, SOD activity was approximately 15% higher than that in the control district, which is also statistically significant, and exceeded the reference range of SOD activity despite advanced age. These results suggested that routine exposure of the residents in the Misasa hot spring district to radon at a concentration about 3 times higher than the national mean induces trace active oxygen in vivo, potentiating products of cancer-suppressive gene and antioxidant function. As the p53 protein level was high in the residents in the Misasa hot spring district, apoptosis of cancer cells may readily occur.     

Purification of a proteinase inhibitor from the plasma of Bothrops jararaca (jararaca)

A proteinase inhibitor was isolated from the plasma of Bothrops jararaca by three chromatographic steps: DEAE Sephacel, Phenyl Sepharose and Bio Gel P200. It inhibited caseinolytic and hemorrhagic activity of the whole venom of B. jararaca. Proteolytic activity of bothropasin and J protease, both metalloproteinases of the venom, were neutralized by the inhibitor. The J protease-inhibitor complex was isolated by gel filtration chromatography in HPLC and the electrophoresis pattern of this complex showed that the interaction between enzyme and inhibitor is not covalent.     

Pathophysiological changes in the airways of asthma patients with aging.

Pathophysiological changes in the airways with aging were examined in 78 patients with bronchial asthma. The FEV1.0% values in patients over the age of 71, and the %MMF, %V50 and %V25 values in those over 51 were significantly lower than those of patients between the ages of 10 and 30. The frequency of lymphocytes in bronchoalveolar lavage (BAL) fluid was significantly higher in patients aged between 61 and 70 than in those aged between 41 and 50 (p < 0.05). The frequency of each clinical asthma type changed with aging; the number of patients with simple bronchoconstriction type (type Ia) decreased with increasing age in patients under the age of 60, and the number of those with bronchiolar obstruction type (type II) increased with aging. The frequency of patients with bronchoconstriction+hypersecretion type (type Ib) showed a peak between the ages of 51 and 60. Bronchial reactivity to methacholine showed a tendency to decrease with aging. The release of histamine from leucocytes induced by Ca ionophore A23187 was significantly higher in patients between the ages of 10 and 30 than in those between the ages of 51 and 60 (p < 0.05) and between 61 and 70 (p < 0.01).     

Mutational activation of the epidermal growth factor receptor down‐regulates major histocompatibility complex class I expression via the extracellular signal‐regulated kinase in non–small cell lung cancer

The efficacy of programmed cell death–1 (PD‐1) blockade in patients with non–small cell lung cancer (NSCLC) positive for epidermal growth factor receptor (EGFR) gene mutations has been found to be limited, but the underlying mechanisms for this poor response have remained obscure. Given that the recognition by T cells of tumor antigens presented by major histocompatibility complex class I (MHC‐I) molecules is essential for an antitumor immune response, we examined the effects of EGFR tyrosine kinase inhibitors (TKIs) on MHC‐I expression in NSCLC cell lines. Appropriate EGFR‐TKIs increased MHC‐I expression at the mRNA and cell surface protein levels in NSCLC cells positive for EGFR mutations including those with the T790M secondary mutation. Trametinib, an inhibitor of the extracellular signal–regulated kinase (ERK) kinase MEK, also increased MHC‐I expression, whereas the phosphatidylinositol 3‐kinase (PI3K) inhibitor buparlisib did not, suggesting that the MEK‐ERK pathway mediates the down‐regulation of MHC‐I expression in response to EGFR activation. Immunohistochemical analysis of EGFR‐mutated NSCLC specimens obtained before and after EGFR‐TKI treatment also revealed down‐regulation of phosphorylated forms of EGFR and ERK in association with up‐regulation of MHC‐I, an increased number of infiltrating CD8⁺ T cells, and increased PD‐1 ligand 1 expression after such treatment. Our results thus suggest that mutational activation of EGFR inhibits MHC‐I expression through the MEK‐ERK pathway in NSCLC and thereby contributes to the poor response of such tumors to immunotherapy. Further studies are warranted to evaluate the relation between EGFR‐MEK‐ERK signaling in and the immune response to EGFR‐mutated NSCLC.     

Clinical studies on steroid-dependent intractable asthma. Comparison between early and late onset of asthma

The various components making for severe intractable asthma were clinically and allergo-immunologically studied in 90 patients with bronchial asthma, by comparison between early onset and late onset groups. 1. In the early onset asthma group, cases with low serum IgE levels showed a stronger tendency toward severe intractable asthma. 2. Late onset asthma cases with negative skin tests and negative specific IgE antibodies to house dust tended more often to be severe intractable cases. 3. There was no correlation between sensitization by specific antigens (house dust and Candida), especially Candida, and a tendency toward severe intractable asthma. 4. Severe intractable asthma might be caused by bronchospasm in cases under 30 years of age, by bronchospasm plus hypersecretion in cases between 31 and 40 years of age, and by bronchospasm plus bronchiolar obstruction in cases over 40 years of age.