Biomedical subjects

J W Son

Publications and source records attributed to J W Son.

At least 19 recordsLinked to original sources

PubMed2006

Ex vivo responses for interferon-gamma and proinflammatory cytokine secretion to low-molecular-weight antigen MTB12 of Mycobacterium tuberculosis during human tuberculosis.

MTB12 protein, also called CFP-2, is a major and early secreted component of Mycobacterium tuberculosis. However, its role during mycobacterial infection has been poorly characterized. In this study, we purified the native MTB12 protein and investigated the profile of MTB12-induced cytokines [interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and interleukin (IL)-6], in early tuberculosis (TB) patients (n = 20) and healthy controls (n = 35). The cytokine profiles were compared with those induced by the 30-kDa antigen (Ag). In healthy controls, MTB12-induced IFN-gamma production was markedly decreased in peripheral blood mononuclear cells compared with 30-kDa Ag-induced IFN-gamma. In TB patients, the mean IFN-gamma level induced by MTB12 was lower than that induced by the 30-kDa Ag, albeit the difference was not significant. After 2 months of anti-TB therapy, both the MTB12- and 30-kDa-induced IFN-gamma levels were significantly increased in TB patients. MTB12-induced TNF-alpha and IL-6 levels were prominently upregulated in monocyte-derived macrophages from TB patients, but they were not significantly different from those induced by the 30-kDa Ag. Further, the activation of p38 mitogen-activated protein kinase and extracellular signal-regulated kinase was required for the induction of TNF-alpha and IL-6 by MTB12, as well as by the 30-kDa Ag. Collectively, these data suggest that the MTB12 protein plays an essential role for proinflammatory responses through the MAPK pathway during the early stages of human TB, even though its T-cell immunoreactivity is weaker than that of the 30-kDa Ag.

Antigens, Bacterial↗

PubMed2001

Efficacy of heparin-coated stent in early setting of acute myocardial infarction.

Primary stenting has been reported to be superior to balloon percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) for recurrent ischemia, target lesion revascularization, and restenosis. However, concerns about early reocclusion or thrombosis after stenting in the very thrombotic environment of acute myocardial infarction still remain. Therefore, postprocedural short-term heparin or GpII(b)/III(a) receptor blockades has been used. The aim of our study was to evaluate the safety, feasibility, and long-term efficacy of heparin-coated stent in the early setting of AMI without postprocedural heparin or GpII(b)/III(a) receptor blockade infusion. We studied 102 consecutive patients presenting to cardiac catheterization laboratory < or = 6 hr from the onset of chest pain. No patients who were implanted with heparin-coated stents received heparin or GpII(b)/III(a) receptor blockade infusion after the procedures, not even patients who showed an angiographically large thrombus burden before stenting. Patients were evaluated for clinical endpoints at 30 days and 6 months. Coronary angiography was required for all patients at 2 weeks and 6 months after the procedure. Angiographic and procedural successes were 100% and 98%, respectively. Two patients (2%) died of heart failure without evidence of reocclusion of stented vessel during the hospitalization and 4 (4%) additional patients died of refractory heart failure within the first 6 months. Major bleeding complication occurred in one patient (1%). Recurrent myocardial infarction developed in one patient at 4 months. Early angiographic follow up at 2 weeks was performed in 88% of all patients, none of whom showed thrombotic stent occlusion. Six-month angiographic follow-up was completed in 71%(64/91) of eligible patients and binary restenosis was present in 17.2% of stented vessels. Eight(8%) patients underwent repeat PTCA. Cardiac event-free survival rate at 6 months was 86.3%. This study demonstrates that heparin-coated stents are safe in the early setting of acute myocardial infarction and no additional heparin infusion after stenting is necessary, which may reduce bleeding complications. Angiographic restenosis rate compares favorably to the binary restenosis rate from other studies with uncoated stents.

Adult↗

PubMed2001

STATT: a titrate-to-goal study of simvastatin in Asian patients with coronary heart disease. Simvastatin Treats Asians to Target.

BACKGROUND: Most published studies on the use of lipid-lowering agents to treat hypercholesterolemia have focused on Western populations, with few data on Asian populations. OBJECTIVE: The Simvastatin Treats Asians to Target (STATT) study used a titrate-to-goal protocol to evaluate the efficacy and tolerability of simvastatin 20 to 80 mg/d in the treatment of Asian patients with coronary heart disease. METHODS: This was a multicenter, open-label, uncontrolled, 14-week study in patients with coronary heart disease and serum low-density lipoprotein cholesterol (LDL-C) levels of 115-180 mg/dL and triglyceride levels of < or = 400 mg/dL. The dose of simvastatin was titrated from 20 to 80 mg/d to achieve the National Cholesterol Education Program (NCEP) LDL-C target of < or = 100 mg/dL. The primary efficacy measure was the percentage of patients achieving the NCEP target. Among secondary measures were the percentage of patients achieving European Society of Cardiology/European Atherosclerosis Society/European Society of Hypertension target LDL-C levels of < or = 115 mg/dL and the percentage change from baseline in lipid parameters. Tolerability was assessed in terms of the overall incidence of adverse experiences and the incidences of the most commonly reported adverse experiences. RESULTS: The intent-to-treat analysis included 133 Asian patients (93 men, 40 women; mean age, 59.5 years), of whom 125 completed 14 weeks of therapy. Their mean blood pressure was 130.2/79.4 mm Hg. Overall, 104 (78.2%) patients treated with simvastatin achieved LDL-C levels < or = 100 mg/dL at week 14, and 125 (94.0%) achieved this target at some point during the study. Similarly, 122 (91.7%) patients achieved an LDL-C level < or = 115 mg/dL at week 14, and 130 (97.7%) achieved this target at some point during the study. Treatment with simvastatin had favorable effects on the lipid profile, producing significant percentage changes from baseline in all parameters (P < 0.001). Simvastatin was well tolerated across the dose range. Overall, 40 patients (30.1%) had > or = 1 clinical adverse experience. Only 14 (10.5%) had adverse experiences that were possibly, probably, or definitely related to study drug; none of these experiences were considered serious. The most common adverse experiences (> or = 3% incidence) were abdominal pain (6%); chest pain (5%); dizziness (4%); and asthenia/fatigue, fibromyalgia, headache, insomnia, and upper respiratory tract infection (3% each). No new or unexpected adverse experiences were seen at the higher doses. CONCLUSIONS: Simvastatin was effective and well tolerated at doses of 20, 40, and 80 mg/d in Asian patients with coronary heart disease. Titration enabled the majority to achieve target LDL-C levels of < or = 100 mg/dL.

Aged↗

PubMed2001

Variant angina with a strong spasmodic trait.

A 55-year-old man came to the hospital because of chest pain, mostly occurring in the early morning at rest. He had to get isosorbide dinitrate intravenously with continuous infusion. Following ergonovine provocation test, total occlusion of mid-left anterior descending artery was identified with marked elevation of ST segment as exercise test showed despite isosorbide dinitrate.

Angina Pectoris, Variant↗

PubMed2001

Effect of hormone replacement therapy on nitric oxide bioactivity and monocyte chemoattractant protein-1 levels.

BACKGROUND: Vascular inflammation plays an important role in the pathogenesis of atherosclerosis. We investigated the effect of hormone replacement therapy (HRT) on vasomotor function and monocyte chemoattractant protein (MCP)-1 levels, an important serological marker of inflammation. METHODS: We administered micronized progesterone (MP) 200 mg for 10 days with conjugated equine estrogen (CEE) 0.625 mg for 25 days and remaining 5 days off cyclically during 2 months to 20 healthy postmenopausal women (PMW). We measured NO bioactivity and plasma levels of MCP-1 before and after HRT in 20 PMW. And we measured plasma levels of MCP-1 in each 20 subjects of premenopausal women, men <50, and men >50 years, respectively. RESULTS: MP combined with CEE significantly improved the percent flow-mediated dilator response to hyperemia relative to baseline measurements (P<0.001). PMW receiving HRT had lower levels of MCP-1 than those not receiving HRT (121+/-38 versus 146+/-44 pg/ml, P<0.001). In all comparisons, subjects with high estrogen status had significantly lower MCP-1 levels than subjects with low estrogen status (P<0.001 by ANOVA). Premenopausal women had lower levels of MCP-1 than men of a similar age (106+/-14 versus 164+/-40 pg/ml, P<0.001). PMW not receiving HRT had similar levels of MCP-1 compared with men of a similar age (146+/-44 versus 143+/-29 pg/ml, P=0.816). Premenopausal women had markedly lower levels of MCP-1 than PMW not receiving HRT (106+/-14 versus 146+/-44 pg/ml, P=0.001). PMW receiving HRT had similar levels of MCP-1 compared with premenopausal women (121+/-38 versus 106+/-14 pg/ml, P=0.323). CONCLUSION: These findings might provide at least a partial explanation for the protection against cardiovascular disease experienced by premenopausal women, and the loss of that protection following menopause.

Age Factors↗

PubMed2001

Differences in sensitization rates to outdoor aeroallergens, especially citrus red mite (Panonychus citri), between urban and rural children.

BACKGROUND: A recent investigation has suggested that citrus red mite (Panonychus citri, CRM) is the most important allergen in citrus-cultivating farmers with asthma and allergic rhinitis. OBJECTIVE: A cross-sectional survey was performed to evaluate the prevalence of asthma and chronic rhinitis symptoms and sensitization to common indoor and outdoor aeroallergens, including CRM and Japanese cedar pollen, in rural and urban Korean children. METHODS: A total of 2,055 children (1,055 subjects living in rural areas with citrus farms and 1,000 controls in urban areas without citrus farms) were enrolled. They were evaluated by a questionnaire, and by skin prick tests with 13 common indoor and outdoor aeroallergens, including CRM and Japanese cedar pollen. RESULTS: The prevalence of wheezing and chronic rhinitis symptoms during the last 12 months was 8.3% and 35.7% in the rural children and 10.5% and 22.4% in the control group. The most common sensitizing allergens in order of decreasing frequency were Dermatophagoides pteronyssinus (26.6%), Dermatoplagoides farinae (22.7%), CRM (14.2%), cockroach (11.3%), and Japanese cedar pollen (9.7%) among the rural children, but the sensitization rates to CRM and Japanese cedar pollen were 1.3% and 0.2% among the control children, respectively. The prevalence of wheeze during the last 12 months was not different between rural children with sensitization to CRM or Japanese cedar pollen and those without sensitization (5.4% vs 6.1%; 6.9% vs 5.9%). However, the prevalence of chronic rhinitis during the last 12 months was higher among those with sensitization to CRM or to Japanese cedar pollen than among those without sensitization (40.8% vs 34.4%; 51.5% vs 33.5%). CONCLUSIONS: CRM is a common sensitizing allergen in rural children, and the sensitization rates to outdoor aeroallergens, especially CRM and Japanese cedar pollen, are very different between children from rural and urban areas in Korea.

Adolescent↗

PubMed2001

Citrus red mite (Panonychus citri) may be an important allergen in the development of asthma among exposed children.

BACKGROUND: Recent investigations have demonstrated that spider mites are important allergens in the development of asthma in fruit-cultivating farmers. OBJECTIVE: The aim of this study was to evaluate the sensitization rate to the citrus red mite (Panonychus citri) in children living in rural areas, and to determine the allergenic cross-reactivity with other mites. METHODS: A total of 7254 children (ages 7-15 years) living in rural areas were enrolled, and each subject was evaluated by a questionnaire and a skin prick test. Allergenic cross-reactivity was evaluated by ELISA inhibition tests. RESULTS: The most common sensitizing allergens were house dust mites, followed by citrus red mite and cockroach. High serum-specific IgE bindings to the citrus red mite were detected in 21 of 100 randomly selected subjects. The prevalence of asthma was higher among those with positive skin responses to the citrus red mite than with negative skin responses to this mite. ELISA inhibition tests showed that IgE bindings to this mite were minimally inhibited with additions of domestic mites. CONCLUSION: Spider mites such as the citrus red mite may be important outdoor allergens among children living in rural areas, and spider mite-derived allergens have unique allergenic determinants compared with domestic mites.

Adolescent↗

PubMed2001

Identification of IgE-binding components of citrus red mite in sera of patients with citrus red mite-induced asthma.

BACKGROUND: Our previous investigations demonstrated that citrus red mite (CRM) antigen could cause IgE-mediated bronchoconstriction in exposed farmers working on citrus farms. OBJECTIVE: This study was performed to confirm IgE-binding components and major allergens within the CRM antigens. METHODS: Ten subjects who had been diagnosed as having CRM-induced asthma were enrolled. Serum-specific IgE antibodies to CRM antigens were measured by using an ELISA. To identify IgE-binding components and major allergens, SDS-PAGE, 2-dimensional PAGE, IgE-immunoblot analysis, and amino acid sequencing of major allergens were performed. RESULTS: All the asthmatic subjects had high specific IgE antibodies to CRMs. Twelve percent SDS-PAGE analysis showed more than 10 protein bands ranging from 6 to 64 kd. SDS-PAGE and IgE-immunoblot analysis with each individual serum showed 5 IgE-binding components (11, 24, 35, 40, and 64 kd), with 2 (24 and 35 kd) of them bound in more than 50% of the study subjects. Two-dimensional PAGE and IgE-immunoblot analysis demonstrated that the major allergen at 24 kd had 2 bands with different isoelectric points of 4.75 and 5.1. Thirty-five kilodaltons had one band with an isoelectric point of 4.75. All amino acid sequencing of the 2 major allergens was performed, which was not homologous with any previously characterized allergens. CONCLUSION: Five IgE-binding components and 2 major allergens (24 and 35 kd) were identified within the CRM antigen. The N-terminal amino acid sequence of the 2 major allergens (24 and 35 kd) was determined.

Adult↗

PubMed2001

Non-lipid effects of statin on hypercholesterolemic patients established to have coronary artery disease who remained hypercholesterolemic while eating a step-II diet.

BACKGROUND: Results of clinical trials of statin therapy demonstrate that an improvement in incidence of cardiovascular end points and coronary stenosis can be achieved. The beneficial effects of statins on clinical events may involve nonlipid mechanisms that affect endothelial function, such as inflammatory responses, formation of thrombi, and stabilization of plaque. OBJECTIVE: To investigate levels of serologic markers, which may be useful surrogates for activity of vascular disease after administration of statin. METHODS: We administered 20-40 mg simvastatin daily for 14 weeks to 13 patients established to have coronary artery disease who remained hypercholesterolemic during step-II diet therapy. RESULTS: Administration of simvastatin significantly lowered lipoprotein levels and the low: high-density lipoprotein cholesterol level ratio and apolipoprotein B:A-I level ratio compared with pretreatment values (P < 0.01). Administration of simvastatin significantly lowered plasma levels of matrix metalloproteinase-9 (MMP-9) and monocyte chemoattractant protein-I [33+/-46 and 13+/-19%, respectively (P = 0.027 and 0.020, respectively)]. Furthermore, administration of simvastatin tended to lower plasma levels of plasminogen activator inhibitor type-1 and tumor necrosis factor-alpha [by 20+/-44 and 13+/-29%, respectively (P= 0.066 and 0.110, respectively)]. There were significant inverse correlations between pretreatment levels of MMP-9 and the degree of change in those levels after administration of simvastatin (r = -0.714, P= 0.005). However, there was no significant correlation between levels of lipoprotein and levels of MMP-9, monocyte chemoattractant protein-I, and plasminogen activator inhibitor type-1 during administration of simvastatin. CONCLUSIONS: Our current data support the hypothesis that nonlipid mechanisms elicited by administration of simvastatin contribute to the decrease in incidence of cardiovascular events and explain the early clinical benefit observed in clinical trials, independent of changes in levels of lipoprotein.

Aged↗

PubMed2001

Linkage between bronchial responsiveness to methacholine and gene markers of IL-4 cytokine gene cluster and T-cell receptor alpha/delta gene complex in Korean nuclear families.

BACKGROUND: Several candidate genes have been reported to be linked to intermediate phenotypes of asthma in Caucasian populations. OBJECTIVE: To evaluate linkage between phenotypes of asthma and gene markers of high affinity IgE receptor-beta gene (D11S97), IL-4 cytokine gene cluster (IL-4R1), and T-cell receptor alpha/delta gene complex (D14S50) in Korean nuclear families. METHODS: Nuclear families (127 probands and their 130 siblings) for the linkage analysis were ascertained through asthmatic children. Linkages between total serum IgE response, skin responses to common aeroallergens, and bronchial responsiveness to methacholine were performed using a sib-pair approach. RESULTS: The square difference of the slope of the dose-response curve (DRS) between sib-pairs with two IL-4R1 identical alleles was smaller than with one or with neither IL-4R1 identical allele (P = 0.004). As for D14S50, the differences of DRS between sib-pairs with two identical alleles and with one identical allele were smaller than with neither identical alleles (P = 0.01). As for D11S97, no significant differences were observed among the groups with identical alleles of two, one or zero. With regard to total serum IgE levels, no significant linkage was found between this phenotype and the above three gene markers. As for skin responses to common aeroallergens, significant evidence was obtained to establish a linkage between this phenotype and the marker IL-4R1 (P = 0.01). However, no significant linkage was found between this phenotype and the markers D11S97 and D14S50. CONCLUSION: The expression of bronchial responsiveness to methacholine may be influenced by genetic factors in the IL-4 cytokine gene cluster and/or T-cell receptor alpha/delta gene complex, but the genetic influence of the FcepsilonRI-beta gene may be minimal in the expression of bronchial responsiveness in Korean nuclear families.

Adolescent↗

PubMed2001

Oviductural carcinoma in B6C3F1 female mice exosed to 0.5 ppm ozone.

The toxicity and carcinogenecity of ozone was evaluated in B6C3F1 mice exposed to 0.5 ppm ozone via inhalation for 12 w, during which no ozone-related deaths occurred. Decreases in mean body weights of both genders exposed to ozone were sporadically seen, and mean absolute and relative weights of several organs from male and female groups receiving ozone were lower than those of respective air-control groups. No ozone-related increased neoplasm incidences were observed in most organs, including the lung; however, oviductural carcinomas were seen in the ozone-exposed females. Although ozone does not induce lung cancer under our experimental condition, it induces oviductural carcinomas in B6C3F1 mice.

Animals↗

PubMed2000

Microsatellite alteration in histologically normal lung tissue of patients with non-small cell lung cancer.

Microsatellite alteration (MSA) has been observed in a fraction of non-small cell lung cancer (NSCLC). Most prior studies regarding MSA in lung cancer have usually used adjacent non-malignant lung tissues as a source of constitutional DNA. However, these normal tissues might have genetic alterations because the entire field of bronchial tree is exposed to the same carcinogenic insult. The aim of this study was to search if MSA is present in the histologically normal lung tissue of patients with NSCLC. Tumor and corresponding normal lung tissue specimens were obtained from 20 patients with NSCLC. Normal lung tissue specimens were obtained from either the opposite end of resected surgical samples or as distant from the tumor as possible. They were examined histopathologically and confirmed as normal by H-E stain. Patients' peripheral lymphocytes were used as the source for the normal DNA. Sixteen markers on 3p and 9p (nine and seven markers, respectively) were used. MSA was detected in seven of 20 (35%) histologically normal lung tissue specimens at a frequency similar to that observed in tumor tissue (eight of 20, 40%). Five cases showed MSA in both normal lung tissue and the corresponding tumor. In these five cases, MSA in normal lung tissue was detected at the same microsatellite markers which MSA was detected in the corresponding tumor. The number and size of novel bands in normal lung tissue was identical to that in tumor tissue except in one case. In which case, the same pattern of MSA was found in both normal lung tissue and corresponding tumor tissue at two markers. However, at one marker, while one identical novel band was detected in normal lung tissue and corresponding tumor tissue, another novel band was found only in tumor tissue. In two of 12 patients whose tumor was negative for the presence of MSA, MSA was detected in normal lung tissue. These results indicate that genetic alterations are widely distributed in the lung tissue of patients with lung cancer and provide considerable support for the field cancerization theory. Screening for MSA in resected normal lung tissue might be a new method to identify patients at high risk for developing second primary lung cancers.

Adult↗

PubMed2000

Impact of abnormal uptakes in bone scan on the prognosis of patients with lung cancer.

The detection of bone metastases is important in the management of patients with lung cancer because bone metastasis has a major impact on the prognosis and choice of treatment modality. Bone scan has been widely used for early detection of bone metastases but its low specificity complicates confirmation of bone scan findings. To evaluate the effects of abnormal bone scan findings on the prognosis of patients with lung cancer, we retrospectively analyzed the effect of abnormal uptakes on the prognosis of patients with primary lung cancer. The overall survival of patients with abnormal bone uptake was not significantly different from those without abnormal uptake. However, the patients with more than two abnormal bone uptakes had significantly shorter survival than those with no abnormal uptake (P<0.05). To confirm the effect of abnormal bone uptakes on survival, we compared the survival curves of three patient groups without knowledge of bone scan findings: group A, stage I-IIIB with more than two abnormal bone uptakes (potential stage IV); group B, stage IIIB with no abnormal bone uptake (true stage IIIB); and group C, stage IV with no abnormal bone uptake. Group A revealed shorter survival than group B (P<0.05). But, there was no significant difference in survival times between group A and group C. In the Cox regression analysis, the presence of more than two abnormal bone uptakes was a significant prognostic factor (P=0.0277), together with performance status, stage, and albumin. These results suggest that one or two abnormal bone uptake at diagnosis did not affect overall survival of the patients, and that the patients with more than two abnormal bone uptakes are considered as clinical stage IV because of high probability of bone metastases.

Bone Neoplasms↗

PubMed2000

Citrus red mite (Panonychus citri) is a common sensitizing allergen among children living around citrus orchards.

BACKGROUND: A recent investigation has suggested that Panonychus citri (citrus red mite) is the most common causative allergen in citrus-cultivating farmers with asthma or allergic rhinitis. OBJECTIVE: A cross-sectional survey was performed to evaluate the prevalence of asthma and sensitization to P. citri among children living around citrus orchards. METHODS: A total of 1,055 children living around citrus orchards were enrolled. There were 544 boys and 511 girls with a mean age of 12.3 (range 7 to 16) years. They were evaluated by the ISAAC questionnaire, and a skin prick test with 13 common aeroallergens including P. citri and Japanese cedar pollen. Children who recorded ever having experienced wheezing on the questionnaire were evaluated by methacholine bronchial provocation test and determined to have asthma if they showed bronchial hyperresponsiveness to methacholine simultaneously. RESULTS: The positive skin test response to one or more inhalant allergens except P. citri was 35.5%, but when including P. citri, the positive response increased to 37.7%. The most common sensitizing allergens in the order of decreasing frequency were Dermatophagoides pteronyssinus (26.6%), D. farinae (22.7%), P. citri (14.2%), cockroach (11.3%), and Japanese cedar pollen (9.7%). Among the children without sensitization to house dust mites, the sensitization rate to P. citri was significantly higher in those 13 and over than in those under 12 (5.8% versus 2.5%, P < .05). The prevalence of asthma was not different between the children with sensitization to P. citri and those without it (5.4% versus 4.0%, P > .05), although the prevalence was higher in those with sensitization to D. pteronyssinus or D. farinae than in those without sensitization to these allergens (7.9% versus 2.9%, P < .05; 9.7% versus 2.6%, P < .05). CONCLUSION: Citrus red mite is a common sensitizing allergen among children living around citrus orchards. The features of sensitization and development of asthma are different between citrus red mite and house dust mites.

Administration, Inhalation↗

PubMed2000

Endobronchial tuberculosis with expectoration of tracheal cartilages.

A case of endotracheal tuberculosis with expectorations of the lateral one-third of the multiple tracheal cartilages is reported. Fibreoptic bronchoscopy revealed caseous materials and loosening of the tracheal cartilages. The patient expectorated cartilaginous material several times before and after fibreoptic bronchoscopy. In spite of the loss of tracheal cartilages, tracheal lumen was maintained with a mild airflow limitation. The remaining two-thirds of the tracheal cartilage rings seemed to be strong enough to support the tracheal lumen opening during the respiratory cycle. Although rare, expectoration of bronchial cartilage can be one of the clinical features of endobronchial tuberculosis.

Adult↗

PubMed2000

Bronchial responsiveness to methacholine is increased in citrus red mite (Panonychus citri)-sensitive children without asthmatic symptoms.

BACKGROUND: A recent investigation has suggested that citrus red mite (Panonychus citri, CRM) is a common sensitizing allergen among children living around citrus farms. OBJECTIVE: A cross-sectional survey was performed to evaluate the bronchial responsiveness to methacholine in CRM-sensitive children without asthmatic symptoms. SUBJECTS AND METHODS: A total of 375 children living around citrus farms were enrolled in this study. There were 201 boys and 174 girls with a mean age of 12.5 (range 7-16) years. Each subject was evaluated by a questionnaire, a skin prick test with 13 common inhalant allergens including CRM, and a methacholine bronchial provocation test (MBPT). RESULTS: Positive rate of MBPT (PC20-methacholine < 25 mg/mL) was higher in atopic rhinitic and atopic control children than in nonatopic rhinitic and nonatopic control subjects (41.3% and 33.3% vs 17.2% and 15.4%, respectively, both P < 0.05). Slope of dose-response curve (DRS, %/mg/mL) was higher in atopic rhinitic children than in nonatopic rhinitic, atopic control and nonatopic control subjects (14.3 +/- 0.87 vs 9.4 +/- 0.72, 10.0 +/- 1.37 and 9.2 +/- 1.51, P < 0.05, respectively). Both the positive rate of MBPT and the DRS were increased in children with positive skin response to CRM than in those without sensitization (48.2% vs 22.9%, P = 0.0001; 15.6 +/- 1.26 vs 10.2 +/- 0.65, P = 0.0001). CONCLUSION: Bronchial responsiveness is increased in citrus red mite-sensitive children even if they have no asthmatic symptoms.

Adolescent↗

PubMed2000

Association of HLA-DRB1()07 and DRB1()04 to citrus red mite (Panonychus citri) and house dust mite sensitive asthma.

BACKGROUND: Specific IgE responses to allergens provide useful models for evaluating the genetic factors that control human immune responses. A recent survey demonstrated that the citrus red mite (Panonychus citri, CRM) is the most important allergen in the development of asthma in citrus farmers. OBJECTIVE: The aim of this study was to evaluate whether susceptibility or resistance to CRM-induced asthma was associated with HLA-DRB1 gene. METHODS: DNAs were extracted from two groups of unrelated Korean adults living around citrus farms: (1) Ninety-one adults with CRM-sensitive asthma; and (2) 98 exposed, healthy nonatopic controls. Genotypes of HLA-DRB1 alleles were carried out using PCR-based methods. RESULTS: Allelic frequency of HLA-DRB1(*)07 was higher in the CRM-sensitive asthmatics compared to the controls (17.6% vs 4.1%, Pc = 0.01). Conversely, the frequency of DRB1*04 was lower in the CRM-sensitive asthmatics compared to the controls (19.8% vs 40.8%, Pc = 0.01). No significant difference was found in the distributions of the other HLA-DRB1 gene-encoded antigens between the two groups. CONCLUSION: HLA-DRB1 genes may be involved in the development of CRM-induced asthma. In addition, HLA-DR7 may increase, and DR4 decrease, the risk of developing the asthma in CRM-exposed adults.

Adult↗

PubMed2000

Specific IgG1 and IgG4 antibodies to citrus red mite in citrus farmers: a study of their relationship to respiratory symptoms.

Citrus red mite (CRM) is known as the most common sensitizing allergen in subjects with asthma and rhinitis working on citrus farms. The aim of this study is to evaluate the role of specific IgG1 (slgG1) and specific IgG4 (slgG4) to CRM in citrus farmers. Questionnaire survey and skin prick test including CRM antigen was done by 136 workers. Specific IgE (slgE), slgG1 and slgG4 to CRM were detected by enzyme-linked immunosorbent assay (ELISA). CRM-sensitive-asthma was diagnosed upon presence of asthmatic symptoms by questionnaire, airway hyperresponsiveness to methacholine and slgE to CRM. CRM-sensitive rhinitis was diagnosed upon presence of rhinitis symptoms and slgE to CRM. Eleven (8.1%) had CRM-sensitive asthma and 25 (18.4%) had CRM-sensitive rhinitis. Significant association was noted between presence of asthmatic symptoms and slgE or slgG4 (p<0.05, respectively), while no significant association was noted in slgG1 (p>0.05). Significant association was noted in the prevalence between slgG4 and slgE (p<0.05), while no significant association was noted between slgG1 and slgG4 or slgE (p<0.05, respectively). There was a significant correlation between slgE and slgG4 level (r=0.39, p<0.05). These findings suggest that the presence of slgG1 to CRM is response to CRM exposure, and further studies will be needed to evaluate the role of slgG4.

Adolescent↗