O6-alkylguanine-DNA alkyltransferase gene polymorphisms and the risk of primary lung cancer

O6-alkylguanine-DNA alkyltransferase (AGT) plays an important role in the repair of O6-alkylguanine adducts, which are major mutagenic lesions produced by environmental carcinogens. Polymorphisms in the AGT gene may affect the capacity to repair DNA damage and thereby have influence on individual's susceptibility to smoking-related cancer. To test this hypothesis, we investigated the potential association of AGT polymorphisms (485C > A, Leu53Leu (C > T) and Leu84Phe] with the risk of lung cancer in a Korean population. The AGT genotypes were determined in 432 lung cancer patients and in 432 healthy controls who were frequency-matched for age and gender. The 485 AA genotype was associated with a significantly increased risk for overall lung cancer as compared with the 485 CC genotype and the combined 485 CC + CA genotype, respectively (adjusted odds ratio (OR) = 1.83, 95% confidence interval (CI) = 1.12-2.99, P = 0.02, and Bonferroni corrected P-value (Pc) = 0.04; and adjusted OR = 1.67, 95% CI = 1.05-2.66, P = 0.03, respectively). When the lung cancer cases were categorized by the tumor histology, the 485 AA genotype was associated with a significantly increased risk of adenocarcinoma (AC) and small cell carcinoma (SmCC), respectively, as compared with the combined 485 CC + CA genotype (adjusted OR = 2.54, 95% CI = 1.39-4.66, P = 0.003; and adjusted OR = 2.19, 95% CI = 1.06-4.55, P = 0.04, respectively). However, the genotype distributions of the Leu53Leu and Leu84Phe polymorphisms were not significantly different between the lung cancer cases and the controls. On a promoter assay, the 485C > A polymorphism did not have an effect on the promoter activity of the AGT gene. These results suggest that the effect of the AGT 485C > A polymorphism on the risk of lung cancer may be secondary to linkage disequilibrium (LD) with either another AGT variant or with a true susceptibility gene, and that the AGT 485C > A polymorphism could be used as a marker for the genetic susceptibility to lung cancer.

Relationship between cyclooxygenase 8473T>C polymorphism and the risk of lung cancer: a case-control study

BACKGROUND

Cyclooxygenase-2 (COX-2) plays an important role in the development of lung cancer. DNA sequence variations in the COX-2 gene may lead to altered COX-2 production and/or activity, and so they cause inter-individual differences in the susceptibility to lung cancer. To test this hypothesis, we investigated the association between the 8473T>C polymorphism in the 3'-untranslated region of the COX-2 gene and the risk of lung cancer in a Korean population.

METHODS

The COX-2 genotypes were determined using PCR-based primer-introduced restriction analysis in 582 lung cancer patients and in 582 healthy controls that were frequency-matched for age and gender.

RESULTS

The distribution of the COX-2 8473T>C genotypes was not significantly different between the overall lung cancer cases and the controls. However, when the cases were categorized by the tumor histology, the combined 8473 TC + CC genotype was associated with a significantly decreased risk of adenocarcinoma as compared with the 8473 TT genotype (adjusted OR = 0.64; 95% CI = 0.46-0.90, P = 0.01). On the stratification analysis, the protective effect of the combined 8473 TC + CC genotype against adenocarcinoma was statistically significant in the males, older individuals and ever-smokers (adjusted OR = 0.59; 95% CI = 0.39-0.91, P = 0.02; adjusted OR = 0.55; 95% CI = 0.33-0.93, P = 0.03; and adjusted OR = 0.57; 95% CI = 0.37-0.87, P = 0.01, respectively).

CONCLUSION

These findings suggest that the COX-2 8473T>C polymorphism could be used as a marker for the genetic susceptibility to adenocarcinoma of the lung.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

One-month parenteral toxicity study of recombinant human basic fibroblast growth factor in dogs

A 1-mo toxicity study followed by a 1-mo recovery period of recombinant human basic fibroblast growth factor (bFGF) was performed using Beagle dogs at doses of 30, 120 or 480 mg/kg/d to estimate the no observed adverse effect level (NOAEL). Subcutaneous thickening was seen and its incidence, as well as that of stiffness of the injection sites, increased with dose. There were neither dead animals nor significant changes of body weight during the experimental period. In addition, no significant bFGF-related changes were found in ophthalmologic and histopathological examination, urinalysis and hematological, biochemical and organ weight parameters. At necropsy, red-brownish spots and/or nodule formations were recognized in a dose-dependent manner. Splenomegaly was noted in the 480 mg/kg group, but these findings had a low incidence in all dose groups. The findings in the dosing period disappeared or were ameliorated during the recovery period. The above data suggests the NOAEL of bFGF in Beagle dogs is >480 mg/kg/d.

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.

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.

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.

Spider mite allergy in apple-cultivating farmers: European red mite (Panonychus ulmi) and two-spotted spider mite (Tetranychus urticae) may be important allergens in the development of work-related asthma and rhinitis symptoms

BACKGROUND

Recent investigations have suggested that the citrus red mite (Panonychus citri) is the most important allergen affecting citrus-cultivating farmers with asthma, allergic rhinitis, or both.

OBJECTIVE

We sought to evaluate type I hypersensitivity to spider mites, particularly the European red mite (Panonychus ulmi) and the two-spotted spider mite (Tetranychus urticae), and to determine the relationship between hypersensitivity to spider mites and respiratory dysfunction.

METHODS

We performed a cross-sectional survey. Questionnaires were given, and skin prick tests for 11 inhalant allergens common in Korea and 2 species of spider mites (European red mite and two-spotted spider mite) were performed in 725 apple-cultivating farmers in Korea.

RESULTS

Results of skin prick tests in the apple farmers indicated that European red mite (23.2%) was the most common sensitizing allergen, followed by Tyrophagus putrescentiae (21.2%), two-spotted spider mite (16.6%), Dermatophagoides farinae (16.3%), D pteronyssinus (14.4%), cockroach (13.1%), and Hop Japanese (Humulus Japonicus) pollen (12.0%). Positive skin responses (mean wheal size >/=3 mm) to one or more of 13 inhalant allergens were found in 48.2% of farmers tested, whereas 40 subjects (8.6%) had an isolated skin response to the spider mites. Among 119 farmers with work-related asthmatic symptoms, the positive skin response rates to European red mite and two-spotted spider mite were 40.4% and 27.0%, respectively. These figures were significantly higher than those found among farmers without work-related symptoms (19.1% and 14.1%, respectively; P <.01). The prevalence of work-related asthma symptoms was higher in farmers with positive skin responses to spider mites than in those with negative skin responses to spider mites and those with positive skin responses to any allergen tested (31.4% vs 15.0% vs 21.0%, respectively; P <.05).

CONCLUSION

Spider mites, particularly European red mite and 2-spotted spider mite, are common sensitizing allergens in apple-cultivating farmers. These spider mites may be important causative allergens in the development of work-related respiratory symptoms in these workers.

Specific IgG, but not specific IgE, antibodies to toluene diisocyanate-human serum albumin conjugate are associated with toluene diisocyanate bronchoprovocation test results

BACKGROUND

The role of specific IgG to toluene diisocyanate (TDI) in the pathogenesis of TDI-induced asthma still remains unclear.

OBJECTIVE

We sought to evaluate the clinical significance of serum-specific IgG to TDI-human serum albumin (HSA) conjugate in subjects with TDI-induced asthma compared with specific IgE antibody.

METHODS

One hundred three subjects were enrolled and divided into 4 groups according to specific bronchoprovocation test (BPT) results: 50 subjects with TDI-induced asthma with positive results on TDI BPT were defined as group 1, 13 symptomatic workers exposed to TDI with negative results on TDI BPT were defined as group 2, 20 unexposed patients with allergic asthma were defined as group 3, and 20 unexposed healthy control subjects were defined as group 4. Serum-specific IgG and IgE antibodies to TDI-HSA conjugate were detected by means of ELISA.

RESULTS

The prevalence of specific IgG antibody to TDI-HSA conjugate was significantly higher in group 1 than in group 2 (46% vs 7.7%, P =.01) or group 3 (0%, P <.01). No significant difference was noted between group 2 and group 3 (P >. 05). However, the prevalence of specific IgE antibody to TDI-HSA conjugate was not significantly different between group 1 and group 2 (14% vs 7.7%, P >.05) or group 2 and group 3 (7.7% vs 0%, P >.05). There was no significant difference in prevalence of specific IgE or specific IgG according to the type of asthmatic response during the TDI BPT (P >.05). Overall, statistically significant association was noted between the prevalence of specific IgE and IgG antibodies in 103 subjects (P <.05), but no difference was noted within group 1 subjects only (P >.05).

CONCLUSION

These findings demonstrate that the presence of serum-specific IgG is closely related to TDI BPT results, and it may contribute to the development of TDI-induced asthma.

Linkage between IgE receptor-mediated histamine releasability from basophils and gene marker of chromosome 11q13

BACKGROUND

The genetics of the regulation of the release of mediators involving the interaction of IgE with cells and their ability to release mediators have not been extensively investigated. With use of the candidate gene approach, it was reported that the gene regulating the beta chain of the high-affinity receptor for IgE is on chromosome 11q13.

OBJECTIVE

To determine whether gene(s) in chromosome 11q13 may control the expression of maximal histamine release from basophil to anti-IgE stimuli, linkage analysis between this phenotype and the gene marker of chromosome 11q13 was performed.

METHODS

Maximal histamine release to anti-IgE and calcium ionophore A23187 and genotyping chromosome 11q13 with use of microsatellite marker (D11S97) were performed in 56 probands with asthma and 59 of their siblings. The linkage was analyzed by affected sib-pair analysis and the quantitative trait locus approach.

RESULTS

Maximal histamine release (mean +/- SE) to anti-IgE and A23187 was 43.3% +/- 3.5% and 30.9 +/- 3.4% in probands and 29.5% +/- 2.6% and 22.2% +/- 2.7 in siblings, respectively. Of 20 sib-pairs with the maximal histamine release to anti-IgE more than 33% (mean plus 1 SD of nonasthmatic controls), 11 (55%) shared 2 D11S97 alleles, 9 (45%) shared 1 allele, and neither sib-pair shared identical alleles, which indicates a significant linkage of maximal histamine to anti-IgE and gene marker of chromosome 11q13 (P =.02). The difference (mean +/- SE) of the maximal histamine release to anti-IgE between each proband and sibling was smaller in sib-pairs with 2 identical alleles than in those with 1 identical allele and with no identical allele (14.1% +/- 2.6% vs 25.8% +/- 3.1% vs 41.0% +/- 4.9%). However, the difference (mean +/- SE) to A23187 between each proband and sibling was not different among the 3 groups (9.7% +/- 1.8% vs 17.9% +/- 3.6% vs 10.4% +/- 4.8%).

CONCLUSION

Maximal histamine release from basophils to anti-IgE stimuli was linked to the gene marker of chromosome 11q13.

Citrus red mite (Panonychus citri) is the most common sensitizing allergen of asthma and rhinitis in citrus farmers

OBJECTIVE

To evaluate type I hypersensitivity to citrus red mite (Panonychus citri), its prevalence, and relationship to respiratory dysfunction, a cross-sectional survey was performed among citrus farmers on Cheju Island, Korea.

MATERIALS AND METHODS

Questionnaires, and skin prick test responses to 11 common inhalant allergens and citrus red mite were performed in 181 citrus farmers, and serum-specific IgE antibodies to citrus red mite were measured by ELISA in sera of 123 subjects. To determine airway hyperresponsiveness, methacholine bronchial provocation tests were performed in 55 subjects who complained of recurrent lower respiratory symptoms.

RESULTS

The prevalence of asthma-based on presence of asthmatic symptoms on the questionnaire and airway hyperresponsiveness to methacholine, and allergic rhinitis based on presence of nasal symptoms on the questionnaire and positive skin-test response were 12.1% and 19.3%, respectively. The positive rate of skin responses to one or more of 11 common inhalant allergens excluding citrus red mite was 17.1%, and if citrus red mite was included, 25.9% of farmers had positive responses. On skin prick tests, citrus red mite (16.5%) was the most common sensitizing allergen, followed by cockroach (11.0%), Dermatophagoides pteronyssinus (9.9%), and D. farinae (9.3%). Among farmers with asthma and allergic rhinitis, the positive skin responses to citrus red mite were noted in 54.5 and 68.5%, respectively. Serum-specific IgE antibodies to citrus red mite were detected in 45 farmers (36. 5%) of the 123 tested, and there was significant correlation between specific IgE level and weal (A/H ratio) to citrus red mite (r = 0.57, P < 0.001). The prevalence of asthma was higher in subjects with positive skin responses or high serum-specific IgE antibodies to citrus red mite than in those without skin response or serum specific IgE (P < 0.05, respectively).

CONCLUSION

Citrus red mite is the most important allergen in citrus farmers with asthma and rhinitis in which causative allergen has not been identified. It should be included in the skin test battery for screening the causative allergen in farmers exposed to citrus red mite.

Skin reactivity to inhalant allergens, total serum IgE levels, and bronchial responsiveness to methacholine are increased in parents of nonatopic asthmatic children

BACKGROUND

Family studies suggest that asthma has an increased familial occurrence, but the hypothesis of a genetic predisposition to IgE response and bronchial hyperresponsiveness (BHR) on the expression of nonatopic asthma is controversial.

OBJECTIVE

The aim of this study was to evaluate familial predisposition to IgE response and BHR on expression of nonatopic asthma.

METHODS

One hundred four parents of nonatopic asthmatic children, 154 parents of atopic asthmatic children, 78 parents of atopic nonasthmatic control children, and 80 parents of nonatopic control children provided questionnaire data and underwent allergy skin prick tests with 10 inhalant allergens and methacholine bronchial provocation tests. Total serum IgE levels were determined in 352 parents (134 with atopic asthmatic children, 87 with nonatopic asthmatic children, 65 with atopic control children, and 66 with nonatopic control children).

RESULTS

Prevalence of asthma, based on questionnaire data and on BHR to methacholine, was higher among parents of nonatopic asthmatic children (10.6%) and atopic asthmatic children (9.1%) than among those of nonatopic control children (1.3%). BHR to methacholine was higher among parents of nonatopic asthmatic children (19.2%) and atopic asthmatic children (16.2%) than among those of atopic and nonatopic control children (5.1% and 1.3%, respectively). The percentage of positive skin test responses to 10 inhalant allergens was higher among parents of atopic asthmatic children (43.9%), nonatopic asthmatic children (39.4%), and atopic control children (38.5%) than among those of nonatopic control children (23.7%). Geometric means (IU/mL +/- SEM) of total serum IgE were higher among parents of atopic and nonatopic control children than among those of nonatopic control children (2.11 +/- 0.05 vs 2. 20 +/- 0.06 vs 2.09 +/- 0.07 vs 1.92 +/- 0.06).

CONCLUSION

Nonatopic asthma runs in families. The prevalence of positive skin test responses to inhalant allergens, BHR to methacholine, and total serum IgE levels is higher among the parents of nonatopic and atopic asthmatic children than among those of nonatopic control children.