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Notes: Background Interleukin-4 receptor α (IL-4Rα), which binds IL-4 and IL-13, is involved in signal transduction of those cytokines that lead to IgE production, and is also a key functional component of the Th2 lymphocyte phenotype.Objective To determine whether IL-4 and IL-4Rα polymorphisms are associated with susceptibility to asthma and whether there are gene–gene interactions between IL-4 and IL-4Rα polymorphisms.Methods We genotyped three groups of Korean children, consisting of 196 atopic asthmatics, 60 non-atopic asthmatics, and 100 healthy children, for an IL-4 promoter polymorphism (C-590T) and three IL-4Rα polymorphisms (Ile50Val, Pro478Ser, and Arg551Gln) using PCR-RFLP (restriction fragment length polymorphism) assays.Results The allele frequencies of the IL-4 (C/T) polymorphism and the Ile50Val and Pro478Ser polymorphisms of IL-4Rα did not differ statistically among the three groups of children. For the Arg551Gln polymorphism, the combined genotype frequency of the Arg/Gln heterozygote and the Arg/Arg homozygote was significantly higher in atopic asthmatics (27.6%) than in healthy children (16.0%) (odds ratio (OR)=1.97, 95% CI (confidence interval)=1.07–3.71). The eosinophil fraction (%) and bronchial responsiveness were higher in children with the Arg/Gln and Arg/Arg genotype than in those with the Gln/Gln genotype (P=0.036 and 0.024, respectively). In asthmatic children, combinations of the IL-4 CT/TT genotype and the IL-4Rα Arg/Gln and Arg/Arg genotypes were associated with significantly increased risk for development of asthma (OR=3.70, 95% CI=1.07–12.78, P=0.038).Conclusions In Korean children, the IL-4Rα Arg551 allele may play a role in susceptibility to atopic asthma and correlate with markers of asthma pathogenesis, including increased eosinophil fraction and enhanced bronchial hyper-responsiveness. In addition, a significant gene–gene interaction between the IL-4-590C and the IL-4Rα Arg551 allele significantly increases an individual's susceptibility to asthma.

Notes: Objectives The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires have shown that the prevalence of childhood asthma is increasing worldwide. Although Asian countries used to have lower prevalence rates of allergic disease than Western countries, this prevalence is increasing in several Asian countries. To determine whether the prevalence of childhood asthma is changing in Korean adolescents, we compared findings from nationwide cross-sectional surveys in 1995 and 2000 on populations of middle-school children using the Korean version of the ISAAC questionnaire.Methods We developed Korean versions of the ISAAC written (WQ) and video (AVQ) questionnaires for allergic diseases. In 1995, the enrolled population consisted of 15 481 children, ages 12–15, and encompassing all three grades in middle school, selected from 34 schools across the nation; the response rate was 97.3%. In 2000, 15 894 children were selected from 31 of the same schools, and the response rate was 96.4%. The SAS system version 8.0 was utilized for all statistical analyses.Results The WQ showed that the lifetime and 12-month prevalence of wheeze did not change from 1995 to 2000. While the 12-month prevalence rates of sleep disturbed by wheezing and night cough increased, the rates of severe attack of wheezing and exercise-induced wheeze did not change, over this period of time. The lifetime prevalence of asthma diagnosis, however, increased significantly, from 2.7% in 1995 to 5.3% in 2000, as did the 12-month prevalence of asthma treatment, from 1.0% in 1995 to 1.9% in 2000. The AVQ also showed increases in the lifetime and 12-month prevalence rates of wheeze at rest, exercise-induced wheeze, nocturnal wheeze, nocturnal cough, and severe wheeze over this period of time. These were especially because of significant increases in the Provincial cities of Korea. Interestingly, the 12-month prevalence of wheeze was consistently high in Cheju with low air pollution indices, whereas this rate was low in Ulsan and Ansan with very high air pollution indices. Risk factor analysis showed that body mass index (BMI), passive smoking, and living with a dog or cat, but not air pollution, were associated with higher risk of wheeze.Conclusions In the 5-year period from 1995 to 2000, the prevalence of asthma symptoms has increased in Korean adolescents, much of it because of increases in Provincial Centers. BMI, passive smoking, and living with a dog or cat are important risk factors. Environmental factors other than air pollution may be associated with increases in asthma, especially in Provincial Centers.

Notes: Background Allergen-specific immunotherapy has proven to be clinically effective in the treatment of patients with atopic asthma; however, the mechanisms are still unclear. Several noted immunological changes include an increase of the allergen-specific IgG antibody, a reduction in the allergen-specific IgE antibody subsequent to transient increase, an allergen-specific T cell shift in cytokine production from Th2 to Th1, and a decrease in quantity and activity of basophils and mast cells.Objective To analyse the changes of basophil histamine release in response to IgE-mediated and non-IgE-mediated stimuli before and after conventional house-dust mite immunotherapy in children who suffer from atopic asthma.Methods Fourteen Dermatophagoides farinae (Df) sensitive asthmatic children with conventional immunotherapy were examined. Basophil histamine releasability was measured 0 months (just before immunotherapy), 4 months and 9 months after immunotherapy. Basophils were stimulated with Df and goat anti-human IgE antibody as IgE-mediated stimuli; and formyl-Met-Leu-Phe (fMLP) and calcium ionophore A23187 as non-IgE-mediated stimuli. Accordingly, the asthma symptom score was used to assess clinical outcome and the skin test reactivity to Df was measured.Results In contrast to pre-immunotherapy activity, 4 and 9 months after immunotherapy there were significant decreases in histamine release by Df and by anti-IgE antibody. The histamine release by fMLP and by calcium ionophore showed no significant changes after immunotherapy. Histamine release by Df demonstrated significant correlation to that by anti-IgE antibody and by fMLP, yet there was no observable correlation between histamine release by Df and by calcium ionophore. The asthma symptom score decreased significantly 4 and 9 months after immunotherapy and showed significant correlation with histamine release by Df. The skin test reactivity (allergen/histamine ratio) remained constant 4 months after immunotherapy, but decreased significantly 9 months after immunotherapy.Conclusion Basophils have the potential to play an important role in the early clinical improvement of conventional immunotherapy in children with atopic asthma, which may be a result of the decreased IgE-mediated histamine releasability during immunotherapy.

Notes: Aims:  PTEN is a recently identified tumour suppressor inactivated in a wide variety of human cancers, including endometrial cancers. Mutation of the PTEN tumour suppressor gene has been reported in approximately 50–83% of endometrial adenocarcinoma. Despite this fact, study of the expression of PTEN protein in human tumours is limited. PTEN protein functions as a tumour suppressor by regulating the cell cycle and survival through signal transduction pathway. PTEN protein was considered to have a dual-specificity phosphatase activity, but it is now known that its principal physiological activity is mainly derived from its lipid phosphatase activity. The cyclin-dependent kinase inhibitor, p27, has been suggested as a downstream target of cell cycle arrest of PTEN in various in vitro studies. In this study, we evaluated the alteration of PTEN protein expression in endometrial carcinoma and assessed its relationship to the expression of p27, the presumed downstream target of PTEN.Methods and results:  Immunohistochemical staining was performed on 66 cases of endometrial carcinoma including 61 endometrioid type and five serous type, using antibodies to PTEN and p27. Loss or decrease of PTEN expression was observed in 66% (40/61 cases) of uterine endometrioid carcinoma, whereas most uterine serous carcinoma (4/5 cases) showed intense PTEN expression. Four (30%) of 13 endometrial hyperplasia synchronous with endometrioid carcinoma demonstrated complete loss of PTEN expression. All endometrioid carcinoma synchronous with PTEN-negative endometrial hyperplasia showed loss of PTEN expression. Alteration of PTEN expression was not correlated with histological grade or stage. Decreased immunoreactivity of p27 was found in 48 cases (79%) of 61 endometrioid carcinoma, and 76% (36 cases) of them also showed loss or decrease of PTEN expression. Four of five uterine serous carcinoma revealed strong p27 immunoreactivity, all of which showed intense PTEN expression. A positive correlation between PTEN and p27 expression was statistically significant (Mantel–Haenszel χ2 test, P=0.001). Immunoreactivity of p27 was not related to histological grade and clinical stage.Conclusion:  These results show that PTEN and p27 are differentially expressed in endometrioid type carcinoma compared with those of the serous type, and suggest that the cyclin-dependent kinase inhibitor, p27, is a downstream target of PTEN-dependent cell cycle arrest in endometrial carcinoma.

Notes: The nucleation and growth of the Si0.5Ge0.5 alloy layer on Si (100) substrate during ion-beam-assisted deposition (IBAD) have been investigated by atomic force microscopy, reflection high-energy electron diffraction, transmission electron microscopy, and double-crystal rocking diffraction. We confirmed that Si0.5Ge0.5 nucleates on Si (100) via the Stranski–Krastanov (SK) mechanism by IBAD, and Ar-ion bombardment suppressed SK growth mode as well as improved crystalline perfection. The epitaxial temperature was observed at 200 °C, and it was much lower than the growth temperature (550–600 °C) in molecular-beam epitaxy (MBE). The χmin value (the ratio of channeling to random backscattering yields) was 10.5% lower than the obtained MBE value. The effect of ion bombardment on nucleation was explained as the result of ion-bombardment-induced dissociation of three-dimensional islands and enhanced surface diffusion, and appeared only at low deposition temperatures where the dissociation of three-dimensional islands is more favorable than the formation of those islands. © 1995 American Institute of Physics.