Biomedical subjects

K-U Min

Publications and source records attributed to K-U Min.

6 recordsLinked to original sources

PubMed2006

Association of genetic variations in neurokinin-2 receptor with enhanced cough sensitivity to capsaicin in chronic cough.

BACKGROUND: Chronic cough is associated with increased sensitivity to inhaled capsaicin, and both tachykinins and their receptors play important roles in the cough reflex. However, associations between polymorphisms of the tachykinin receptor genes and cough sensitivity in patients with non-productive chronic cough have not been reported. METHODS: Direct sequencing was used to identify single nucleotide polymorphisms (SNPs) in the genes for the neurokinin-1 and neurokinin-2 receptors (NK-1R and NK-2R, respectively). Informative non-synonymous SNPs were scored using the single base extension method for 312 patients with chronic cough and for 100 age matched healthy controls. The cough response to capsaicin was recorded for 312 patients with chronic cough, and the potential genetic association between cough sensitivity to capsaicin and the NK-1R and NK-2R genotypes was evaluated. RESULTS: Two informative SNPs were identified in NK-2R (Gly231Glu and Arg375His), whereas no informative SNP was found in NK-1R. After adjusting for atopy, sex, age, and smoking, the prevalence of enhanced cough sensitivity to capsaicin was higher in the chronic cough patients with the 231Glu allele (p = 0.004; OR 1.69 (95% CI 1.18 to 2.42)) and the 231Glu_375Arg haplotype (p = 0.003; OR 1.71 (95% CI 1.20 to 2.24)). Moreover, the lowest capsaicin concentration to cause five consecutive coughs (C5) was significantly lower in patients with 231Glu (mean (SD) 44.1 (53.2) v 60.9 (55.8) microM/l, p = 0.04) and those with 231Glu_375Arg (43.2 (52.7) v 69.6 (52.0) microM/l, p = 0.03). CONCLUSIONS: The results of this study suggest that NK-2R gene polymorphisms are involved in the enhanced cough sensitivity to capsaicin of patients with chronic cough.

Adult↗

PubMed2005

Association between bronchodilating response to short-acting beta-agonist and non-synonymous single-nucleotide polymorphisms of beta-adrenoceptor gene.

BACKGROUND: With beta-agonists being the most widely used agents in the treatment of asthma, in vitro studies reported that beta(2)-adrenergic receptor (ADRB2) polymorphisms are associated with agonist-promoted down-regulation. OBJECTIVE: The present population-based study aimed to evaluate the association between bronchodilating response to inhaled short-acting beta-agonist and two non-synonymous single-nucleotide polymorphisms (SNPs) of ADRB2 (ADRB2-16 and ADRB2-27). METHODS: Two hundred and nine children with reduction in forced expiratory volume in 1 s of more than 20% on methacholine bronchial challenge underwent bronchodilating response testing 5 min after the inhalation of 200 mug of albuterol. Of these 209, 195 gave peripheral blood for genotyping of ADRB2 polymorphisms. RESULTS: The bronchodilating response was significantly higher in subjects with the homozygous Arg16 than in those with the homozygous Gly16. It was further demonstrated that haplotype pairs of the homozygous Arg16Gln27 and of the heterozygous Arg16Gln27/Gly16Glu27 showed the highest bronchodilating responses, and the haplotype pairs of the homozygous Gly16Gln27 the lowest response. As a whole, the bronchodilating response was more positively associated with the combined quantity of Arg16 and Glu27 polymorphisms than with that of Arg16 alone. CONCLUSION: Non-synonymous SNPs of ADRB2 at codons 16 and 27 is significantly associated with bronchodilating response to inhaled short acting beta-agonists.

Adolescent↗

PubMed2003

Allergen-specific conventional immunotherapy decreases immunoglobulin E-mediated basophil histamine releasability.

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.

Adolescent↗

PubMed2002

Coding single nucleotide polymorphism in the high-affinity immunoglobulin E receptor b chain (FcepsilonRI-beta) gene is associated with immunoglobulin E receptor-mediated histamine release from basophils.

BACKGROUND: Our previous work on linkage analysis showed that histamine release from basophils to anti-IgE stimuli was linked to the gene marker of chromosome 11q13, where the beta chain of the high-affinity receptor for IgE (FcepsilonRI-beta) is located. OBJECTIVE: To evaluate the association between FcepsilonRI-mediated histamine release from basophils and four bi-allelic single nucleotide polymorphisms of the FcepsilonRI-beta gene. METHODS: Phenotypes of asthma, such as maximal histamine release from basophils and atopy, were measured from 80 randomly recruited asthmatic children. Polymorphisms of the FcepsilonRI-beta gene were determined by PCR-based methods. RESULTS: The polymorphism in exon 7, resulting in Glu to Gly substitution, was significantly associated with histamine release from basophils to anti-IgE stimuli, but not with total IgE levels and skin test responses to aeroallergens. CONCLUSION: This study supports a role for the FcepsilonRI-beta gene in the expression of high affinity IgE receptor-mediated histamine release from basophils.

Adolescent↗

PubMed2002

Relationship between sensitization to citrus red mite (Panonychus citri) and the prevalence of atopic diseases in adolescents living near citrus orchards.

BACKGROUND: Recent investigations have demonstrated that the citrus red mite (Panonychus citri, CRM) is the most important allergen in citrus fruit farmers with asthma and rhinitis and a common sensitizing allergen in children living near citrus orchards. OBJECTIVE: To evaluate the sensitization rate to CRM and the association between sensitization to CRM and atopic diseases, such as athma, allergic rhinitis and atopic dermatitis, in adolescents living in rural areas with citrus orchards. METHODS: A total of 2005 adolescents (aged from 16 to 18 years) living in rural areas with citrus orchards were enrolled. Subjects were evaluated by a questionnaire and a skin prick test with 11 common aeroallergens including CRM. RESULTS: The prevalences of current wheeze, rhinoconjuntivitis, and eczema on the questionnaire were 13.0%, 13.6%, and 8.8%, respectively. On skin prick tests, the most common sensitizing allergen was CRM [20.6%], followed by Dermatophagoides pteronyssinus (18.5%), D. farinae (14.6%) and cockroach (9.8%). The prevalence of current eczema was significantly associated with the sensitization to CRM (OR = 1.9, 95% CI 1.3-2.9), although the prevalence of current wheeze and rhinoconjunctivitis was not associated with it. Among adolescents living near citrus orchards, however, the prevalences of current wheeze and rhinoconjuncitivitis were significantly higher in those with sensitization to only CRM than in those without sensitization to any allergens (20.3% vs. 14.1% and 20.3% vs. 15.0%, P < 0.05, respectively). CONCLUSION: CRM is the most common sensitizing allergen in adolescents living in rural areas with citrus orchards, and sensitization to CRM was significantly associated with the prevalence of atopic dermatitis.

Adolescent↗

PubMed2002

Role of environmental exposure to spider mites in the sensitization and the clinical manifestation of asthma and rhinitis in children and adolescents living in rural and urban areas.

BACKGROUND: Spider mites such as the citrus red mite and the two-spotted spider mite have been demonstrated to be important allergens for fruit cultivating farmers. OBJECTIVE: To evaluate the role of environmental exposure to spider mites in the sensitization and the clinical manifestations of asthma and rhinitis in children and adolescents living in urban and rural areas. METHODS: A total of 16,624 subjects (aged 7 to 18 years) living in urban (metropolitan and non-metropolitan) and rural areas (apple orchards and citrus orchards) in Korea were evaluated by questionnaire and skin prick test for 11 common aeroallergens, including citrus red mite (CRM) and two-spotted spider mite (TSM). RESULTS: The positive skin response rates to TSM were 4.2% of 1,563 metropolitan subjects, 3.8% of 5,568 non-metropolitan subjects and 6.5% of 1,464 subjects living nearby apple farms, and that to CRM 15.6% of 8,029 living nearby citrus farms. The prevalence of current wheeze and rhinitis as reported on a questionnaire was higher among those with a history of visiting fruit farms once or more per year than among those without it (10% vs. 7.1%, 32.8% vs. 26.7%, for wheezing and rhinitis, respectively). Among those with wheezing or rhinitis, the positive skin responses to TSM or CRM were also higher among those with a history of visiting fruit farms than among those without one (11.2% vs. 6.6%, 13.0% vs. 6.6%, respectively), although the positive skin responses to house dust mites were similar in the both groups. CONCLUSION: Spider mites are common sensitizing allergens in children and adolescents exposed to them, and environmental exposure to these mites may represent an important risk factor in the sensitization and the clinical manifestations of asthma and rhinitis in children and adolescents living in rural and urban areas.

Adolescent↗