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ABSTRACT: Motor vehicle emissions have become a major source of air pollution. Contributions of motor vehicle emissions to exposure to toxic metals such as manganese remain inconclusive. This study investigates the relationship between the concentration of manganese in cord blood and exposure to criteria air pollutants during pregnancy. A total of 1526 mother-newborn pairs were recruited by stratified sampling between April, 2004 and July, 2005. The newborns' mothers completed questionnaires that collected information on their demographic characteristics, medical histories, and living environments. Cord blood samples were collected at birth and analyzed by inductively coupled plasma mass spectrometry for manganese. Information about criteria air pollutants which included CO, NO(2), ozone, SO(2), and PM(10) was obtained from monitoring stations run by the Taiwan Environmental Agency. Using the Arc9 Geographic Information System's kriging method, the concentration of each criteria pollutant was estimated at each newborn's residence. The geometric mean for cord blood manganese concentrations was 47.0 μg/L (GSD=1.4). After adjusting for confounding factors such as family income, maternal education, maternal smoking, alcohol drinking during pregnancy, maternal age, child gender, parity, gestational age, and birth season, the results of a multiple linear regression model indicated that cord blood manganese concentration was significantly associated with NO(2) concentration in each trimester, as well as the whole duration of gestation. Between the pregnant women exposed to the highest and those to the lowest quartile of NO(2), a 6 μg/L difference in cord blood manganese concentration was found. This finding suggests that despite other sources of manganese exposure, maternal exposure to ambient NO(2), a surrogate for traffic emission, significantly contributed to fetal cord blood manganese level. Further study is warranted to determine whether the contribution of manganese due to traffic emission causes adverse health effects in fetuses.
Environmental Research 12/2011; 112:1-7. · 3.40 Impact Factor
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ABSTRACT: Atopic dermatitis (AD) is the most common skin disease in childhood and the first step of atopic march. This study aimed to investigate whether AD in children could be better predicted by biologic markers (cord blood IgE [cbIgE], LT-αNcoI alleles, and FcεRI-β E237G genotypes) and maternal mentality during pregnancy, taking into account gender, socio-demographic factors, and parental atopy. From 2001 to 2005, 1264 mother-infant pairs were recruited to participate in a birth cohort study. Prenatal questionnaire was used to collect family history, maternal gestational conditions and mentality, and environmental exposures. Cord blood was collected and assayed for genotypes and IgE levels. Phone interviews at 6 months and 2 yrs of age were conducted to inquire children's health status, including AD occurrence. In addition to the known risk factors such as gender, maternal education, and parental atopy, biomarkers and maternal mentality during pregnancy were screened by logistic regression as candidate predictors of AD. Area-under-curve (AUC) statistic from receiver-operating characteristic (ROC) curve analysis was used to compare two predicting models with and without biomarkers and maternal mentality. A total of 730 pairs completed the prenatal questionnaire and phone interview and were included in final analysis. The prevalence of ever having physician-diagnosed AD by 2-yr-olds was 5.9%. Elevated cbIgE levels (≥0.5 kU/l), LT-αNcoI alleles, FcεRI-β E237G genotype, and maternal psychologic stress during pregnancy were significantly associated with AD. Comparison with AUCs of the classic model (including gender, maternal education, and parental atopy), the model adding cbIgE levels, genotypes in cytokine genes, and maternal stress (model 2) showed higher ability to discriminate between children with and without AD (AUC statistics: 0.63 [95% CI = 0.60-0.67] vs. 0.73 [95% CI = 0.70-0.76], respectively; model comparison, p = 0.027). We conclude that elevated cbIgE, LT-α and FcεRI-β genotypes, and maternal stress during pregnancy were associated with ever having physician-diagnosed AD in 2-yr-old children and increased the predictive ability for AD after taking into account gender, maternal education, and parental atopic history.
Pediatric Allergy and Immunology 05/2011; 22(7):695-703. · 2.46 Impact Factor
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ABSTRACT: High cord blood immunoglobulin E (cbIgE) is known to be associated with increased risks of atopic diseases in childhood. The relationship between genetic polymorphisms and high cbIgE has not been well documented. A cross-sectional study was conducted to assess the association between cbIgE and genetic polymorphisms of interleukin (IL)-4 -590C/T, the beta-subunit of the high-affinity receptor for IgE (FcepsilonRI-beta) E237G, lymphotoxin (LT)-alphaNcoI alleles, and tumor necrosis factor (TNF)-alpha -308G/A. A total of 320 mother-neonate pairs were recruited from four maternity hospitals from different locations of Taiwan. Cord blood was obtained and assayed for cbIgE. Polymerase chain reaction followed by restriction fragment length polymorphism was used to assess the genotypes. Three hundred pairs of mothers and neonates were included in the final analysis. Infants with IL-4 -590 C allele were found to have higher risk of elevated cbIgE (> or =0.35 IU/ml, 24.3%) (p = 0.004). After adjusting for gender, birth order, maternal age, and history of allergic disease in maternal and paternal families, odds ratios for CC and CT genotypes were 4.41 and 3.16 (95% confidence interval 0.78-22.67, and 1.66-6.13), respectively, using TT genotype as reference. The genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha were not associated with cbIgE before or after the adjustment. Our finding suggested a significant association of cbIgE with genetic polymorphism of IL-4 -590C/T, but not with the genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha.
Pediatric Allergy and Immunology 11/2006; 17(7):489-94. · 2.46 Impact Factor
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ABSTRACT: The aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor that can be activated by a diverse synthetic and naturally-occurring chemicals, such as the halogenated aromatic hydrocarbons (HAHs) and the non-halogenated polycyclic aromatic hydrocarbons (PAHs). The liganded AHR modulates the genetic activity of a variety of xenobiotic-responsive genes, including cytochrome P4501A1 (CYP1A1). The tyrosinase inhibitor 1-phenyl-2-thiourea (PTU) is widely used in zebrafish research to suppress pigmentation in developing embryos/fry. Here we showed that 0.2 mM PTU induced a basal level of CYP1A1 transcription in zebrafish embryonic integument as early as 24 h postfertilization (hpf) stage. Subsequently, PTU induced CYP1A1 transcription in blood vessels at 36 hpf. During larval stage, the liver and all pharyngeal arch vessels of PTU-treated embryos exhibited CYP1A1 transcription as well. Comparing to TCDD, PTU induces CYP1A1 transcription with much lower efficacy in zebrafish embryos. Coincubating the embryos with PTU and TCDD led to repressing TCDD-induced CYP1A1 transcription. Mechanistic studies indicated that both of PTU- and TCDD-mediated CYP1A1 transcriptions are modulated by the same AHR-ARNT signaling pathway.
Biochemical Pharmacology 08/2004; 68(1):63-71. · 4.70 Impact Factor
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ABSTRACT: We examined the activity of the bone morphogenetic protein 4 (BMP4) promoter in zebrafish embryos via transient and stable transgenic expression analyses in order to obtain a better understanding of the regulation of BMP4 tissue-specific expression. Transient expression studies showed that the 9.0-kb BMP4 promoter/upstream region drove green fluorescent protein (GFP) expression mainly in the heart. Deletion analyses indicated the existence of multiple regulatory elements in the 7.5-kb BMP4 promoter/proximal upstream region. In addition, a coinjection experiment further demonstrated the 2.4-kb Bgl II-Hind III DNA region contains major positive regulatory elements. In addition, stable transgenic lines were established to further confirm the heart-specificity of this segment in BMP4 promoter. The results showed that GFP was mainly localized in the myocardium of developing ventricles of 48-hpf (hours postfertilization), 72-hpf, and 100-hpf transgenic F(1) embryos. Together, these results indicate that the 7.5-kb BMP4 promoter/proximal upstream region specifically contains regulatory elements for BMP4 expression in the heart, while regulatory elements for other endogenous BMP4-expressing tissues may reside in more distal regions and/or in introns.
genesis 12/2003; 37(3):103-12. · 2.53 Impact Factor
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ABSTRACT: To investigate whether different myosin heavy chain (MHC) isoforms may constitute myofibrils in the trunk and tail musculature and if their respective expression may be regulated by spadetail (spt) and no tail (brachyury), we identified and characterized mRNA expression patterns of an embryonic- and tail muscle-specific MHC gene (named myhz2) during zebrafish development in wild type, spt, and ntl mutant embryos. The identified myhz2 MHC gene encodes a polypeptide containing 1,935 amino acids. Deduced amino acid comparisons showed that myhz2 MHC shared 92.6% sequence identity with that of carp fast skeletal MHC. Temporal and spatial myhz2 MHC mRNA expression patterns were analyzed by quantitative RT-PCR and whole-mount in situ hybridization using primer pairs and probes designed from the 3'-untranslated region (UTR). Temporally myhz2 MHC mRNA appears in pharyngula embryos and peaks in protruding-mouth larvae. The expression level decreased in 7-day-old hatching larvae, and mRNA expression was not detectable in adult fish. Spatially in pharyngula embryos, mRNA was localized only in the tail somite region, while in long-pec embryos, transcripts were also expressed in the two cranial muscle elements of the adductor mandibulae and medial rectus, as well as in pectoral fin muscles and the tail muscle region. Myhz2 MHC mRNA was expressed in most cranial muscle elements, pectoral fin muscles, and the tail muscle region of 3-day-old hatching larvae. In contrast, no expression of myhz2 MHC mRNA could be observed in spt prim-15 mutant embryos. In spt long-pec mutant embryos, transcripts were expressed in two cranial muscle elements and the tail muscle region, but not in pectoral fin muscles, while only trace amounts of myhz2 MHC mRNA were expressed in the remaining tail muscle region of 38 hpf and long-pec ntl mutant embryos.
Molecular Reproduction and Development 01/2003; 63(4):422-9. · 2.53 Impact Factor
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ABSTRACT: Recently we isolated a homolog of the Drosophila single-minded (sim) gene from a zebrafish cDNA library. The 4380-bp of zebrafish sim cDNA encodes a polypeptide of 585 amino acids with strikingly conserved bHLH and PAS A/B domains in the amino-terminal region. During embryogenesis, sim mRNA appears in the animal hemisphere as early as 3 h post-fertilization and is expressed in a widespread pattern throughout the epiblast at the 75% epiboly stage. During the segmentation stage, sim mRNA is prominently expressed in the primordium of the hindbrain and appears as a transverse stripe in the epithelial layers of the mid-diencephalic boundary (MDB). During the pharyngula stage, sim is no longer expressed in the hindbrain, but continues to be expressed in the MDB and extends to the caudal diencephalon along the ventral midline. In addition, sim mRNA is prominent in the two pharyngeal arches. During the larval stage, sim mRNA is transcribed in the esophagus, liver, pancreas, and intestine. In contrast, sim mRNA is no longer detectable in the forebrain after hatching. In adult fish, sim is widely expressed in brain, eyes, gill, heart, liver, and intestine.
Mechanisms of Development 02/2002; 110(1-2):231-5. · 2.83 Impact Factor