Search

This study aimed to use an air-liquid interface (ALI) exposure system to simulate the inhalation exposure of motorcycle exhaust particulates (MEPs) and then investigate the benchmark dose (BMD) of MEPs by evaluating cell relative viability (CRV) in lung epithelial BEAS-2B cells.The MEPs dose was characterized by measuring the number concentration (NC), surface area concentration (SAC), and mass concentration (MC). BEAS-2B cells were exposed to MEPs at different concentrationsOur results reveal that BMD of NC and SAC were estimated by the best-fitting Hill model, while MC was estimated by Polynomial model. The BMDL for CRV following ALI exposure to MEPs were as follows: 364.2#/cmThese results indicate that MEPs exposure

In recent years, it has been a hot research topic to study the interaction between atomic ensemble and cavities, and many researches have been done in this regard. In such a system, some atoms are trapped in the cavity, which can be used to study their dynamic characteristics, e.g., the evolution of photon numbers and photon transition. The Jaynes-Cummings model is an important model for studying the dynamic characteristics of the cavity-atom system, which is based on the interaction between a single two-level atom and the cavity field. Recently, coherent photon control in cavity under specific conditions has become an important part of quantum computing and communication. It is worth noting that the tunable photon transmission and all-optical switches based on the cavity have already aroused much interest and have been used in many areas. The quantum information and networks are mostly rooted in complex optical devices, which may show nonreciprocal or asymmetric photon transport. In this paper, we demonstrate that by using an optical closed-loop system the unconventional photon transport can be realized with two mutually perpendicular cavities coupled through external fiber and a two-level atom placed on the intersection. This three-mode system supports two orthogonal propagation directions, that is to say, and the interactions among probe fields are mutually perpendicular. Without ignoring the spontaneous decay of the natural atom, the complex and controllable quantum interference induced by the efficient hybrid interaction of the light, cavity modes, and the atom in such a closed-loop structure can result in a few interesting symmetric and asymmetric photon transport behaviors, i.e. coherent perfect synthesis and coherent perfect reflection. Aside from these compelling properties, the group velocity can also be modulated, i.e., fast and slow light effect. All of these processes can be dynamically controlled by using the probe field phase difference, the tunneling coupling between two cavities and the coupling between the cavity and the atom. Importantly, due to so many advantages, such a tunable scheme can be readily extended to some optical devices, e.g., the switch and the router that is challenging to conventional optical devices.

To detect the cytokines levels in serums of patients with trichloroethylene-induced hypersensitivity dermatitis and explore the effect biomarkers associated with this disease.Twenty-two patients with TCE-induced hypersensitivity dermatitis, twenty-two healthy TCE-exposed workers from the same workshops with patients and twenty-two comparable unexposed controls were recruited in this study. Eight cytokines in serums from all subjects were detected using Liquid Suspended Biochip; the correlation among the eight cytokines including interleukin (IL)-1β (IL-1β), IL-5, IL-8, IL-10, interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), macrophage chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1β (MIP-1β) and the correlation between IL-5 and eosinophil count were analyzed.The medians of levels of IL-1β, IFN-γ, IL-5, IL-10, MCP-1, MIP-1β, IL-8 among patients were 0.15, 80.13, 2.95, 6.45, 83.83, 1057.90, 440.22 pg/ml, respectively, which were higher than those among the TCE-exposed workers (0.09, 16.93, 0.11, 0.07, 28.75, 241.07, 28.26 pg/ml, respectively, all P values0.01) and unexposed controls (0.09, 3.14, 0.11, 0.07, 25.27, 209.64, 207.34 pg/ml, respectively, all P values0.01). The median of level of TNF-α among the patients was 13.26 pg/ml, which was significantly higher than that among TCE-exposed workers (4.87 pg/ml, P0.01) but not among unexposed controls; the median of level of IL-5 among the TCE-exposed workers was 0.11 pg/ml, which was significantly higher than that among the unexposed controls (0.11 pg/ml, P0.01). The median of levels of IL-8 among the unexposed controls was 207.34 pg/ml, which was significantly higher than that among the TCE-exposed workers (28.26 pg/ml, P0.01). In case group, except for correlation of TNF-α and IFN-γ, TNF-α and IL-5, the significant positive correlations were found among any two cytokines (r(IL-1β,IFN-γ) = 0.500, r(IL-1β,TNF-α) = 0.348, r(IL-1β,MCP-1) = 0.537, r(IL-1β,MIP-1β) = 0.477, r(IL-1β,IL-8) = 0.466, r(IL-1β,IL-5) = 0.610, r(IL-1β,IL-10) = 0.626, r(IFN-γ,MCP-1) = 0.460, r(IFN-γ,MIP-1β) = 0.491, r(IFN-γ,IL-8) = 0.322, r(IFN-γ,IL-5) = 0.532, r(IFN-γ,IL-10) = 0.511, r(TNF-α,MCP-1) = 0.325, r(TNF-α,MIP-1β) = 0.283, r(TNF-α,IL-8) = 0.430, r(TNF-α,IL-10) = 0.271, r(MCP-1,MIP-1β) = 0.659, r(MCP-1,IL-8) = 0.526, r(MCP-1,IL-5) = 0.504, r(MCP-1,IL-10) = 0.614, r(MIP-1β,IL-8) = 0.601, r(MIP-1β,IL-5) = 0.451, r(MIP-1β,IL-10) = 0.579, r(IL-8,IL-5) = 0.255, r(IL-8,IL-10) = 0.403, r(IL-5,IL-10) = 0.798, all P values0.05). The median of level of IL-5 among the patients with high eosinophils counts was 8.92 pg/ml, which was significantly higher than that among the patients with low eosinophils counts (1.04 pg/ml, P0.05).The abnormal production of IL-1β, IFN-γ, TNF-α, IL-8, MCP-1, MIP-1β, IL-5 and IL-10 was related with the pathogenesis of hypersensitivity dermatitis induced by TCE. These cytokines could be used as referential indexes in the early health surveillance and clinic disease treatment.

To study the effects of trichloroethylene (TCE) to lymphocyte subsets among exposed workers, and explore the early immunological effect biomarkers for prevention of hypersensitivity dermatitis induced by TCE.Twenty-eight patients with TCE-induced hypersensitivity dermatitis, 56 healthy TCE-exposed workers from the same workshops with patients, and 28 comparable unexposed controls were recruited in this study. The total lymphocyte count and the major lymphocyte subsets including T cell, CD4(+) T cell, CD8(+) T cell, B cell, NK cell in peripheral blood were measured by Flow Cytometer analysis and Standard blood count analysis.The total lymphocyte count and T cell, CD4(+) T cell, CD8(+) T cell among patients (median at 2810.00, 1846.17, 831.87, 904.05 cell counts/µl blood) were significantly increased compared with TCE-exposed workers (median at 2101.00, 1218.59, 643.87, 482.81 cell counts/µl blood, Z = -3.19, -4.96, -3.22, -4.99, P0.001) and unexposed controls (median at 1900.00, 1223.60, 558.60, 325.80 cell counts/µl blood, Z = -3.30, -4.46, -3.45, -5.03, P0.001), the NK cell and CD3(+)CD4(+)/CD3(+)CD8(+) ratio among patients (median at 255.50 cell counts/µl blood and 1.11) were significantly decreased compared with the unexposed controls (median at 642.60 cell counts/µl blood and 1.96, Z = -3.56 and -3.11, P0.01). Meanwhile, for the exposed workers, the CD8(+) T cell (median at 482.81 cell counts/µl blood) was significantly increased and the NK cell and CD3(+)CD4(+)/CD3(+)CD8(+) ratio (median at 318.76 cell counts/µl blood and 1.27) were significantly decreased compared with unexposed controls (median at 325.80 and 642.60 cell counts/µl blood and 1.96, Z = -2.63, -3.52, -2.29, P0.05).Occupational exposure to TCE could affect the lymphocyte subsets, especially T cell and NK cell. The total lymphocyte count, T cell and CD4(+) T cell might be effect biomarkers for subjects with hypersensitivity dermatitis among TCE-exposed workers.

To elucidate the mechanism of carcinogenesis induced by coke oven emissions by investigating the cell genetic damage index and the methylation of O⁶-methylguanine-DNA methyltransferase (MGMT).The human bronchial epithelial cell 16HBE was treated by 1 µmol/L B(a)P for 48 h, and then was exposed continuously to either 1‰ dimethyl sulfoxide (DMSO) or organic extracts of coke oven emission (OE-COE) for five days at the concentrations of 0, 2.5, 5.0, 10.0 and 20.0 µg/ml. The methylation-specific PCR (MSP-PCR), RT-PCR and immunoblotting were applied to detect the methylation status, changes of mRNA and protein of MGMT, respectively. Single cell gel electrophoresis was used to detect DNA damage induced by OE-COE.Compared with the control group (DMSO), there was a significant hypermethylation in all study groups, along with the suppression of mRNA and protein in a dose-dependent manner, and the gradation ratio of them was 1.0, 0.96, 0.96, 0.85, 0.32 and 1.0, 1.0, 1.1, 0.41, 0.52, separately. There was a significant DNA damage with a dose-effect relationship in all study groups (F = 41.22, P0.05), and the comet Olive tail moment was (2.98 ± 1.43), (4.76 ± 1.79), (10.09 ± 1.75), (11.38 ± 1.77), (11.67 ± 1.88). The further study found that the index of DNA damage was negatively correlated to the expression of MGMT mRNA and its protein.The DNA damage induced by COE might be associated with the suppression of MGMT caused by its hypermethylation.

Generalized glucocorticoid resistance syndrome is a rare familial or sporadic condition characterized by generalized, partial, target-tissue insensitivity to glucocorticoids. This syndrome is partially caused by mutations in the human glucocorticoid receptor (hGR) gene. The clinical spectrum of generalized glucocorticoid resistance is broad, ranging from fatigue or no symptoms to severe hypertension with hypokalemic alkalosis. The purpose of this study was to explore the genetic disorder of glucocorticoid resistance syndrome.We identified a 56-year-old male patient diagnosed with generalized glucocorticoid resistance syndrome accompanied with an adrenocortical adenoma. This asymptomatic patient referred to Peking Union Medical College Hospital for treatment of his adrenal incidentaloma. Endocrinological evaluation consistently revealed his elevated serum cortisol level. Total RNA was extracted from the patient's peripheral blood mononuclear leukocytes (PBMLs) and entire coding region of hGR alpha was amplified by reverse transcription (RT)-PCR. To confirm the possible mutation identified by sequencing RT-PCR products, genomic DNA sequence of hGR gene from the patient and 50 healthy controls was analyzed by PCR and directly sequencing.A heterozygotic (C→T) substitution at nucleotide position of 1667 (exon 5) in GR alpha gene was found in this patient by sequencing of RT-PCR products of hGR gene. This substitution was also identified at genomic DNA level and it was absent in 100 chromosomes from 50 unrelated health controls. This substitution resulted in a threonine to isoleucine substitution (ACT→ATT) at amino acid 556 in the ligand-binding domain of GR alpha.Generalized glucocorticoid resistance in this patient might be caused by a novel heterozygotic mutation in the ligand-binding domain of the GR alpha.

To clarify the possible gene mutations in luteinizing hormone(LH) receptor gene in a boy with LH independent precocious puberty and probe the mechanism the of diseases caused by LH receptor activating mutations.(1) Describe the clinical manifestations and laboratory data in a 5-year-old boy with LH independent precocious puberty. (2) Peripheral leukocytes were collected from the proband, his parents and other 20 normal puberty developed males. PCR and direct DNA sequence of 11 exons in LH receptors gene were conducted.(1) The proband was diagnosed to have LH independent precocious puberty according to the clinical symptoms and the laboratory tests. (2) A germ-line heterozygous point mutation in the 11 exon of LH receptor gene was found in the proband and his mother: c1193 T--C leading to amino acid change with M398T, which causes consecutively an activation of the LH receptor. (3) Other nucleotide changes in the proband and other normal males include c935 A--G (N312S) and c1065 --C (same sense mutation).(1) A germ-line heterozygous point mutation in the LH receptor gene with M398T leads to consecutively activation of the LH receptor and LH independent precocious puberty. (2) The same point mutation does not have any influence on the puberty development, menstruation and productive functions of the proband's mother. (3) The LH receptor gene has possible polymorphism in the Han ethnic population.

To explore the association between polycyclic aromatic hydrocarbons (PAHs) exposure and telomere length (TL), so as to investigate the effective biomarkers to evaluate the genetic damage in peripheral blood of workers exposed to PAHs.The exposure group consisted of 145 coke-oven workers (including 30 top-oven workers, 76 side-oven workers and 39 bottom-oven workers), and the non-exposure control group comprised 68 medical staffs. At 6 hours after the weekend duty shift, the samples of urine and 1 ml venous blood were collected from each subject. Airborne benzene-soluble matter (BSM) and particulate-phase B(a)P in the working environment of coke-oven and controls were sampled and analyzed. The concentration of urinary 1-hydroxypyrene (1-OHPyr) was determined. A real-time PCR method was used to determine the relative telomere length (RTL) of genomic DNA in peripheral blood. The relationship between the RTL and external exposure of PAHs, the potential factors which might have influence on TL were analyzed.The medians of air BSM and particulate-phase B(a)P were higher in coke-oven (BSM: 328.6 µg/m(3); B(a)P: 926.9 ng/m(3)) than those in control working environment (BSM:97.8 µg/m(3); B(a)P: 49.1 ng/m(3)). The level of 1-OHPyr among coke-oven workers was significantly higher than that of non-exposed group (12.2 µmol/mol Cr vs 0.7 µmol/mol Cr; t = 26.971, P0.01). RTL in coke-oven workers were significantly shorter than those of controls (1.10 ± 0.75 vs 1.43 ± 1.06; t = 2.263, P = 0.026), and after adjusting for cigarettes per day and urinary 1-OHPyr, the significant difference was still observed (F(adju) = 5.496, P(adju) = 0.020). Stratification analysis found that RTL among the male and non-drinking groups in coke-oven workers were shorter than those the same sex and alcohol using status in controls (1.08 ± 0.73 vs 1.51 ± 1.10, F = 9.212, P = 0.003; 0.96 ± 0.38 vs 1.26 ± 0.46, F = 6.484, P = 0.012). Significant correlation between RTL and age was found (r = -0.284, P = 0.019) in non-exposure group.PAH-exposure has effect on TL of genomic DNA in peripheral blood, which is mainly observed in the male and non-drinking groups between PAH-exposed workers and controls. It indicates that TL of genomic DNA in peripheral blood might be an effective biomarker as PAH-induced genetic damage.

To investigate cytotoxicity and genotoxicity of benzo(a)pyrene (B(a)P) by 16HBE-CYP1A1 cells which are human bronchial epithelial cell with CYP1A1 transformed.Expression of CYP1A1 and mEH of cell models were tested by real-time quantitative polymerase chain reaction. Cells were treated with 0, 1, 5, 10 and 20 micromol/L B(a)P for 24 h. Adverse effects of B(a)P were tested by cytokinesis-block micronucleus (CBMN) cytome assays. Cytotoxicity was assessed by the nuclear division index (NDI), frequency of necrotic and apoptotic cells. Genetic damages were assessed by frequencies of CBMN, nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs).High levels of CYP1A1 and mEH were found in 16HBE-CYP1A1 cells (relative mRNA content was 7.8 x 10(-4) and 0.030 respectively). In 16HBE-CYP1A1 cells, NDI were decreased in 1, 5, 10 and 20 micromol/L B(a)P treated groups, 1.92 +/- 0.04, 1.71 +/- 0.01, 1.61 +/- 0.04, and 1.41 +/- 0.01, respectively; and lower than control group (2.08 +/- 0.03). Compared with control group ((82.67 +/- 6.66)%), the binucleated cells ratios were decreased, (76.33 +/- 3.51)%, (66.33 +/- 0.58)%, (51.67 +/- 1.53)% and (39.0 +/- 1.0)% respectively.Necrotic cells ratios were (1.93 +/- 0.42)%, (2.20 +/- 0.53)%, (8.07 +/- 0.90)% and (15.27 +/- 2.80)%, respectively, higher than control group ((0.47 +/- 0.11)%). The differences were significant (F values were 899.94, 303.33, 240.87, P0.01). Apoptotic cells were increased at lower groups and decreased to normal at higher groups treated by B(a)P. They were (1.20 +/- 0.53)%, (2.00 +/- 0.20)%, (1.47 +/- 0.12)%, (1.20 +/- 0.00)% and (1.20 +/- 0.00)%, respectively. Analysis on biomarkers of genetic damage, the significant dose-effect relationship were observed in NPBs and NBUDs (F values were 50.23, 121.09, P0.01, respectively). Frequencies of NPBs were (4.67 +/- 2.89) per thousand, (7.33 +/- 1.53) per thousand, (10.67 +/- 2.08) per thousand and (11.00 +/- 1.00) per thousand respectively. Frequencies of NBUDs were (2.33 +/- 0.58) per thousand, (4.00 +/- 1.00) per thousand, (5.00 +/- 1.00) per thousand, and (7.67 +/- 1.16) per thousand respectively. However, the dose-relationship of CBMN last only to 10 micromol/L B(a)P treated groups in 16HBE-CYP1A1 cells, and frequencies of CBMN were (8.33 +/- 3.21) per thousand, (14.67 +/- 1.15) per thousand, respectively. Frequency of CBMN was (16.67 +/- 2.88) per thousand in 20 micromol/L B(a)P treated group, lower than 10 micromol/L B(a)P treated group ((17.67 +/- 2.08) per thousand). In 16HBEV control cells, the cytotoxicity was found only in higher B(a)P treated groups and frequencies of CBMN, NPBs and NBUDs were increased also. While no significant differences were observed between 5, 10, 20 micromol/L B(a)P treated groups (they were (6.37 +/- 2.08) per thousand, (9.33 +/- 1.52) per thousand, (9.33 +/- 3.21) per thousand; (4.33 +/- 1.53) per thousand, (6.00 +/- 2.65) per thousand, (5.33 +/- 1.53) per thousand and (2.33 +/- 0.58) per thousand, (3.33 +/- 1.16) per thousand, (3.67 +/- 1.16) per thousand, respectively).The genetic damages were more severe after treated with activated B(a)P, which may be induced by decreased NDI, increased necrotic cells and inhibition of apoptosis.

To explore the effect of 2,5-hexanedione (2,5-HD) on the levels of nerve growth factor (NGF) in sciatic nerve of rats and motor-neurons.A total of 50 Wistar rats were randomly designed into five groups and intoxicated with 400 mgxkg(-1)xd(-1) 2,5-HD for 0, 7, 14, 21, 28 d. Immunohistochemistry and real-time PCR were used to detect the levels of NGF and NGF mRNA. Motor neuron VSC4.1 cells were administrated with 0, 2.5, 5.0, 10.0, 20.0 mmol/L 2,5-HD for 24 h and 10.0 mmol/L 2,5-HD was chosen to intoxicated VSC4.1 cells for 0, 1, 3, 6, 12, 24, 48 h respectively. Immunofluorescence technique was selected to detect the levels of NGF.The NGF level in sciatic nerve of rats administrated with 400 mgxkg(-1)xd(-1) 2,5-HD showed increase tendency at begin and then decrease after exposure. The NGF mRNA level in 14 d (2(-DeltaDeltaCt)= 3.46), 21 d (2(-DeltaDeltaCt)= 5.28) and 28 d (2(-DeltaDeltaCt)= 3.10) were higher than those in 0 d (2(-DeltaDeltaCt)= 1) and 7 d (2(-DeltaDeltaCt)= 0.78). In vitro tests of VSC4.1 cells showed that NGF levels in 5.0 mmol/L (43.24 +/- 7.52), 10.0 mmol/L (43.48 +/- 10.86) and 20.0 mmol/L (63.13 +/- 10.68) were higher than those in 0 mmol/L (16.32 +/- 4.20)(q values were 19.92, 19.72, 32.78, respectively, P0.01) and 2.5 mmol/L (19.78 +/- 2.66) (q values were 17.50, 17.42, 30.63, respectively, P0.01) in 24 h and the NGF level in 20.0 mmol/L was higher than those in 5.0 mmol/L (q = 13.04, P0.01) and 10.0 mmol/L (q = 11.71, P0.01). The NGF levels of VSC4.1 cells with 10.0 mmol/L 2,5-HD in 6 h (18.66 +/- 2.89), 12 h (23.14 +/- 6.08), 24 h (27.66 +/- 6.11) and 48 h (17.25 +/- 3.05) were increased compared with that in 0 h (10.18 +/- 1.81) (q values were 9.64, 15.74, 21.76, 8.50, respectively, P0.01), 1 h (9.31 +/- 1.28) (q values were 10.28, 16.17, 21.95, 9.20, respectively, P0.01) and 3 h (10.44 +/- 2.13) (q values were 9.25, 15.24, 21.17, 8.10, respectively, P0.01), and NGF levels in 12 h and 24 h increased compared with those in 6 h (q values were 5.24, 10.77, respectively, P0.01) and 48 h (q values were 7.31, 13.26, respectively, P0.01).2,5-HD could increase NGF levels in sciatic nerve of rats and motor-neurons, and the dose or time dependent effects were observed in this study.

To seek new effect biomarkers as to evaluating the chromosomal damage in peripheral blood lymphocytes in coke-oven workers who were exposed to polycyclic aromatic hydrocarbons (PAHs).One hundred and fifty-eight coke-oven workers and 69 controls were recruited in this study. Nucleoplasmic bridges and nuclear buds were counted as indicators of chromosomal damage in terms of cytokinesis-block micronucleus (CBMN) test. Occupational history, age, sex, smoking and alcohol using status of all subjects were collected by questionnaire.Frequencies of nucleoplasmic bridge in coke-oven workers were (9.41 +/- 3.73)% per hundred, and the frequencies of nuclear buds were (7.13 +/- 4.01)% per hundred, which were significantly higher (P0.01) than those of controls (1.88 +/- 1.49)% per hundred and (2.20 +/- 1.73)% per hundred respectively. The dose-effect relationships between nucleoplasmic bridges or nuclear buds and PAHs exposure levels were identified. Compared with male coke-oven workers, female workers had less nucleoplasmic bridges or nuclear buds. No effects of age, smoking and alcohol using were found on nucleoplasmic bridges or nuclear buds among coke-oven workers.Nucleoplasmic bridges and nuclear buds might be effect biomarkers in coke-oven workers.

To investigate the sensitivity to bleomycin (BLM) in peripheral blood lymphocytes (PBL) among coke-oven workers.Ninty-four coke-oven workers with exposure to a high level of polycyclic aromatic hydrocarbons and 64 non-coke-oven workers (control) were recruited into this study. PBL was challenged by 8 microg/ml BLM, a known carcinogen, to induce certain amount of DNA damage, the difference of olive tail moment (TM) measured by comet assay before and after BLM treatment reflected the sensitivity towards mutagens.The distribution of age, sex, and prevalence of smoking and drinking were not significantly different between these two groups. The geometric mean of urinary 1-hydroxypyrene (1-OHP) was significantly higher in coke-oven workers than in controls (9.0 versus 1.5 microg/L, t = -9.317, P0.01). The coke-oven workers showed significantly higher sensitivity to BLM than controls (17.7 versus 14.9, t = -2.583, P = 0.01). A large inter-group difference in sensitivity to BLM was observed in both controls and coke-oven workers. Stratification analysis revealed the significant association between high 1-OHP level (9.0 microg/L) and increased sensitivity to BLM (F = 4.001, P = 0.05) among coke-oven workers. Smoking subjects showed a significant higher value of sensitivity than nonsmokers in controls but not in coke-oven workers. No significant difference was observed between age, drinking status, coking history or external exposure class and BLM sensitivity.Exposure to coke oven emission could increase the sensitivity to mutagens, which might be a reason of high incidence of lung cancer among coke-oven workers.

To investigate the association of polymorphisms of nucleotide excision repair genes and chromosomal damage in peripheral blood lymphocytes among coke-oven workers.The genotypes of ERCC1 C19007T, ERCC2 C22541A, ERCC2 G23591A, ERCC2 A35931C, ERCC4 T30028C, ERCC5 G3507C and ERCC6 A3368G among 140 coke-oven workers and 66 non-coke-oven controls were determined by PCR-PFLP methods. Chromosomal damage was detected by cytokinesis-block micronucleus (CBMN) assay.Multivariate analysis of covariance revealed that in coke-oven workers, the ERCC1 19007 CC genotype exhibited significantly higher CBMN frequency [(1.05 +/- 0.68)%] than did the CT [(0.81 +/- 0.66)%] (P = 0.01) or TT [(0.66 +/- 0.37)%] (P = 0.05) or CT + TT genotypes [(0.75 +/- 0.63)%] (P = 0.004). For the ERCC6 A3368G polymorphism, AA genotype exhibited significantly higher CBMN frequency [(1.00 +/- 0.69)%] than did the AG [(0.67 +/- 0.42)%] (P = 0.05) or AG + GG genotypes [(0.66 +/- 0.41)%] (P = 0.02). Stratification analysis found the significant association between the two polymorphisms, ERCC1 C19007T and ERCC6 A3368G, and the CBMN frequencies were most pronounced in older workers. In addition, for the polymorphism of ERCC2 G23591A, GA carriers had significantly higher CBMN frequencies [(1.40 +/- 0.63)%] than those GG carriers [(0.98 +/- 0.59)%] (P = 0.01) in older workers.Our results suggested that polymorphisms of ERCC1 C19007T, ERCC6 A3368G and ERCC2 G23591A were associated with the CBMN frequencies in coke-oven workers.

To investigate the association between polymorphisms of DNA repair gene XRCC1 and DNA damage in peripheral blood lymphocytes among workers exposed to formaldehyde.One hundred and fifty-one workers exposed to formaldehyde from plywood factories and one hundred and twelve workers without occupational exposure to formaldehyde were recruited into this study. DNA damage levels were measured by comet assay. The polymorphisms of XRCC1 gene were analyzed by polymerase chain reaction(PCR) with restriction fragment length polymorphism(RFLP) method. The multiple covariance analysis was used to compare olive trail moment and comet trail length adjusted confounding factors.In formaldehyde exposed workers, after ages, smoking and drinking status and occupational exposure level were adjusted, means of Olive trail moment and comet trail length in the subjects with variant genotype at Arg280 His site (geometric means 4.30 and 13.42 respectively) were higher than subjects with wild type homozygote (geometric means 3.38 and 11.71 respectively), the differences were significant (Olive trail moment: P0.05, comet trail length: P0.01) . No associations between the polymorphisms at other three sites in XRCC1 gene and means of olive trail moment and comet trail length in exposure workers were found.The polymorphisms of XRCC1 gene may modulate the effects of DNA damages induced by formaldehyde in workers.

To investigate the association between MTHFR gene variances and chromosomal damage levels in peripheral blood lymphocyte in coke-oven workers exposed to polycyclic aromatic hydrocarbons (PAHs).One-hundred and forty coke-oven workers who exposed to a high level of PAHs and sixty-six non-exposed controls were selected as the study subjects. Chromosomal damage in peripheral lymphocyte was measured by the cytokinesis-block micronucleus (CBMN) assay. Urinary 1-hydroxypyrene (1-OHP) levels were measured as the internal dose of PAHs exposure. Two single nucleotide polymorphisms(SNPs) in MTHFR gene, including C677T, A1298C were detected by PCR-RFLP. The MTHFR haplotypes were estimated by Bayesian statistical method with the software of PHASE Version 2.1. The associations between haplotype pairs and CBMN were assessed by analysis of covariance in the coke-oven workers and controls.The variant allele frequencies for MTHFRC677T and A1298C were 0.56 and 0.16 respectively, which consistent with Hardy-Weinberg equilibrium. There was linkage disequilibrium between the two SNPs (D' = 0.99) in this study. Four haplotypes were calculated by PHASE, in terms of 677T - 1298A, 677C-1298A, 677C-1298C and 677T-1298C, the frequencies were 0.555,0.279,0.163 and 0.003 respectively. In coke-oven workers, the frequencies of total micronucleus of non-677C-1298A/677C-1298A haplotype pair was significantly higher than 677C-1298A/677C-1298A (1.00 +/- 0.67 vs 0.60 +/- 0.41, P = 0.04). The frequencies of total micronucleus of 677T-1298A/677T-1298A haplotype pair was significantly higher than 677C-1298A/677C-1298A (1.08 +/- 0.71 vs 0.60 +/- 0.41, P = 0.04). In coke-oven workers, the frequencies of total micronucleus among the different SNPs were not significant differences, either in the controls.The haplotypes of MTHFR gene might be one genetic susceptibility factors of PAH induced chromosomal damage in coke-oven workers.

To investigate the association between genetic polymorphisms of human leukocyte antigen-DQ (HLA-DQ) and susceptibility to trichloroethylene (TCE)-induced severe generalized dermatitis.A case-control study was conducted which included 112 patients with TCE-induced severe generalized dermatitis and 142 healthy controls exposed to TCE in the same workshop. The DNA sequences in exon2 of HLA-DQA1 and HLA-DQB1 were performed by direct sequencing of polymerase chain reaction (PCR) products. The frequencies distribution of allelic genotypes and codon polymorphisms were compared.The frequencies of DQA1*0201 and 060101/0602 in cases [7.6% (17/224) and 16.1% (36/224)] were significantly higher than those of the exposed controls [3.5% (10/284) and 7.0% (20/284)], while frequencies of DQA1*0103 and 050101/0503/0505 in cases [5.8% (13/224) and 8.9% (20/224)] were significantly lower than those of exposed controls [10.9% (31/284) and 17.3% (49/284)]. In terms of codon polymorphisms, there were 5 codons of DQA1 (25, 41, 52, 54 and 69) showing significant differences between cases and controls. There were no significant differences in the frequencies of allelic genotypes of HLA-DQB1 between cases and exposed controls.The genetic polymorphisms of HLA-DQA1 might be one of the factors influencing the individual susceptibility to TCE-induced severe generalized dermatitis.

Investigate the genetic polymorphisms of aldehyde dehydrogenase (ALDH) and alcohol dehydrogenase (ADH), major enzymes involving the trichloroethylene (TCE) metabolism, associated with susceptibility to TCE-induced medicamentosa-like dermatitis.The study included 108 patients with TCE-induced medicamentosa-like dermatitis and 145 healthy controls exposed to TCE who were engaged in the same workplace, and frequency matched by sex and age. The genotypes of ADH2, ADH3 and ALDH2 were analyzed by polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP), and distribution of genotype and odds ratio were calculated.There were no differences in the frequencies of genotypes of ADH2 and ADH3 between cases and exposed controls. The frequency of heterozygous ALDH2 * 1/ * 2 plus homozygous ALDH2 * 2/ * 2 in cases was significantly lower than that in exposed controls (27.8% vs 43.4%, P = 0.011), and it decreased the risk of TCE-induced medicamentosa-like dermatitis (OR = 0.50, 95% CI = 0.29-0.85).The active ALDH2 might be one of the factors influencing the individual susceptibility to TCE-induced medicamentosa-like dermatitis.

To investigate the association of XRCC1 polymorphisms and chromosomal damage levels in peripheral blood lymphocyte in coke-oven workers.The study included 141 coke-oven workers who exposed to a high level of polycyclic aromahaplotpetic hydrocarbon and 66 non-exposed controls. Urinary 1-hydroxypyrene and chromosome damage in peripheral lymphocyte were measured. Four -tagging single nucleotide polymorphisms in XRCC1 gene, including C26304T, G27466A, G28152A and G36189A, were detected and the XRCC1 haplotypes were estimated by using an extension of Clark algorithm. The associations between haplotype pairs and micronuclei data were assessed by analysis of covariance in the exposed and non-exposed groups.The geometric means of urinary 1-hydroxypyrene levels in coke-oven workers and the controls were 12.0 and 0.7 micromol/mol Cr respectively (P0.01). The cytokinesis-block micronucleus cytokinesis-block micronucleus frequencies (number of micronucleus per 1 000 binucleated lymphocytes) was significantly higher in coke-oven workers (0.95 +/- 0.66)% than in the controls (0.40 +/- 0.36)%, P0.01. The haplotype CGGG was associated with the decreased frequencies of total micronucleus, and the haplotypes TGGG (P = 0.01) and CGAG (P0.05) were associated with the increased frequencies of total micronucleus in the multivariate analysis with adjustment for covariates among coke-oven workers.The genetic polymorphisms of XRCC1 gene could influence the chromosome damage levels in coke-oven workers.

To investigate the association of polymorphisms of metabolic and DNA repair enzyme genes and DNA damage in peripheral blood lymphocytes in coke-oven workers.One hundred and forty-four coke-oven workers and 50 controls were recruited in this study. Urinary 1-hydroxypyrene (1-OHP) levels were measured as the internal dose of polycyclic aromatic hydrocarbons exposure. DNA damage was detected by alkaline comet assay, and the value of 1.74 was used as the cut-off value to determine whether the individual's DNA damage was positive. The genotypes of CYP1A1, CYP2E1, GSTP1, NQO1, mEH and XRCC1 were determined by PCR-based methods. With adjustment for urinary 1-OHP, age, sex, multiple analysis of covariance was used to study the association between genotypes and the ln-transformed olive TM and multiple logistic regression was used to calculate the adjusted OR and the 95% CI for the risk of DNA damage.In 144 coke-oven workers, with adjustment for urinary 1-OHP, coking history and sex, the olive TM was significantly higher with XRCC1 280His allele than those with Arg allele (5.6 vs. 2.8, P0.01). The subjects with XRCC1 280His allele also have significantly higher risk for DNA damage than subjects with Arg allele (adjusted OR = 2.66, 95% CI = 1.00-7.14, P = 0.05) and the subjects with GSTP1 104Val allele have higher risk for DNA damage than subjects with Ile allele (adjusted OR = 1.90, 95% CI = 0.94-3.85, P = 0.07).XRCC1 and GSTP1 polymorphisms might influence the susceptibility of DNA damage in occupational PAH-exposed coke-oven workers.

To investigate the changes of certain immunological indexes in development of Guinea Pig allergic dermatitis induced by trichloroethylene (TCE).The Guinea Pig model of TCE-induced allergic dermatitis was established by Guinea Pig Maximisation Test. IgG levels in serum were measured by sandwich enzyme immunoassay. The splenic T lymphocytes ConA-stimulated proliferation function and natural killer (NK) cell activity were detected by MTT assay and micro-LDH release assay, respectively.The sensitization rate of TCE was 66.7%. The IgG level in serum of TCE-sensitized animals was significantly higher than that in normal animals (P0.05). No obvious differences in Splenic T lymphocytes proliferation index and NK cell activity between TCE-sensitized and normal animals were found (P0.05).Humoral immunity may play an important role in development of allergic dermatitis induced by TCE.

To study albumin adduct with naphthalene metabolites, namely 1,2-naphthoquinone (1,2-NPQ) and 1,4-naphthoquinone (1,4-NPQ), as a potential biomarker for intermediate/long-term exposure to polycyclic aromatic hydrocarbons (PAH) in coke oven workers.Twenty-eight coke oven workers and 22 control workers were recruited from a cokery. Spot urine and venous blood samples were collected from the workers after four continuously working days and personal information was obtained by questionnaire. Plasma albumin adduct was detected with gas chromatography-mass spectrometry.Albumin adduct with 1,2-1,4-NPQ (1,2-NPQ and 1,4-NPQ), respectively, were detected in all coke oven workers and controls. Median plasma level of 1,2-NPQ-Alb in coke oven workers was significantly higher than that in controls (76.6 pmol/g vs. 44.9 pmol/g, P0.01). However, there was no significant difference in plasma median level of 1,4-NPQ-Alb between the two groups (48.6 pmol/g vs. 44.2 pmol/g, P0.05). Plasma level of 1,2-NPQ-Alb was significantly higher than that of 1,4-NPQ-Alb in coke oven workers. Urine levels of naphthalene, 1-naphthol, 2-naphthol and 1-pyrenol in coke oven workers correlated significantly with their plasma level of 1,2-NPQ-Alb (Pearson coefficient of correlation greater than 0.371, P0.01), but did not do significantly with 1,4-NPQ-Alb.Plasma level of 1,2-NPQ-Alb could effectively reflect their magnitude of personal internal dose of exposure to air PAH, so it could be used as a potential biomarker to evaluate their intermediate/long-term exposure to PAH in coke oven workers.

To investigate the associations of polymorphisms of metabolic enzyme genes with urinary 1-hydroxypyrene levels in coke oven workers.One hundred and forty-eight workers from a coke oven plant and 69 controls without occupational PAHs exposure were selected in this study. Urinary 1-hydroxypyrene was detected by high performance liquid chromatography with florescence detector. The genotypes at I462V site in exon 7 of CYP1A1 gene, GSTM1, GSTT1, I105V site in GSTP1gene, Pst1 and Dra1 sites in CYP2E1 gene, P187S site in NQO1 gene, Kpn1, BamH1 and Taq1 sites in NAT2 gene, and H113Y, R139H sites in mEH gene were determined by PCR-based methods. Personal information including occupational exposure history, age, sex, smoking and drinking status was collected by the questionnaire.The level of urinary 1-hydroxypyrene in coke oven workers [(5.61 +/- 1.04) mol/mol Cr] was higher than that in control [(0.74 +/- 0.32) micro mol/mol Cr]. After adjusting external occupational exposure category and smoking, coke oven workers with variant homozygotes at H113Y site of mEH gene had significantly higher urinary 1-hydroxypyrene concentrations than those with heterozygotes, and wild homozygotes (6.41 +/- 1.09 vs. 6.24 +/- 1.08, and 4.62 +/- 0.95 micro mol/mol Cr, P0.05), and gene-gene interaction was found between CYP1A1 and mEH.Genetic polymorphism of mEH gene could be a susceptible biomarker in coke oven workers which was involved in the individual susceptibility on metabolism of PAHs.

To investigate the relationship between lymphocyte DNA damage and polycyclic aromatic hydrocarbons (PAHs) exposure in coke oven workers.Two hundred and thirty-five coke oven workers and 30 controls were selected in this study. Alkaline single-cell gel electrophoresis was used to evaluate the lymphocyte DNA damage, HPLC was employed to measure 1-hydroxypyrene levels in spot urine samples which were obtained at the end of a workweek (4 days of 8 hours/day) and personal information including occupational exposure, age, sex, smoking and drinking status was collected by the questionnaire.The lymphocyte DNA damage level expressed as olive moment in coke oven workers was significantly higher than that of controls [2.47 (0.22 approximately 46.68) vs 0.94 (0.42 approximately 4.21), P0.01], and correlation between urinary 1-hydroxypyrene concentrations and olive moment was found (Spearman Partial correlation coefficient = 0.22, P0.01) in coke oven workers. The 1.9 of olive moment value was used as the limit to determine whether the subject DNA damage was positive. The coke oven workers had significantly higher risk in DNA damage (adjusted OR = 5.38, 95% CI = 2.07 approximately 14.08) than did controls, and dose-response relationships were also found between external exposure (exposure category) or internal doses (urinary 1-hydroxypyrene) and DNA damage.There are dose-effect and dose-response relationships between PAHs exposure and lymphocyte DNA damage in coke oven workers.

To investigate the association between polymorphisms of metabolic enzyme genes and chromosomal damage risk in peripheral blood lymphocytes among coke oven workers.One hundred and fourty-nine coke oven workers and 24 referents without occupational polycyclic aromatic hydrocarbons (PAH) exposure were recruited in this study. Urinary 1-hydroxypyrene levels were measured as the internal dose of PAH exposure. The 6 per 1 000 of micronucleus value was used as the cut-off value to determine whether the individual's chromosomal damage was positive. The genotypes of CYP1A1, GSTM1, GSTT1, GSTP1, CYP2E1, NQO1, NAT2 and mEH genes were determined by PCR-based methods. Multiple logistic regression was used to calculate the adjusted ORs and the 95% CI for the risk of chromosomal damage and to analyze the gene-gene interaction.In 173 subjects, after adjusting the occupational exposure, age, sex, smoking and drinking status, the subjects with GSTM1 null genotype have significantly higher risk for chromosomal damage than subjects with GSTM1 positive genotype (adjusted OR = 2.01, 95% CI = 1.03 -3.91). Compared with the wild homozygotes at P187S site of NQO1 gene, the variant homozygotes have significantly higher risk for chromosomal damage (adjusted OR = 3.18, 95% CI = 1.18 - 8.62). The subjects with variant allele at H113Y site of mEH gene have significantly lower risk for chromosomal damage (adjusted OR = 0.40, 95% CI = 0.19 - 0.88). No significant associations were found for other gene polymorphisms and chromosomal damage risk. In addition, the gene-gene interactions were also found among GSTM1, NQO1 gene P187S and mEH gene H113Y polymorphisms for the risk of chromosomal damage risk.Significant associations between genetic polymorphisms in GSTM1, NQO1 and mEH gene and risk for chromosomal damage were found among occupational PAH-exposed workers, which related to the mechanism of PAH carcinogenesis.

To investigate DNA and chromosome damage in peripheral blood lymphocyte of coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs).One hundred and thirty-seven coke oven workers and 50 controls without occupational PAHs exposure were investigated. Comet assay and cytokinesis-block micronucleus (CBMN) detection were used to evaluate DNA and chromosomal damage levels in peripheral blood lymphocyte. Urinary 1-hydroxypyrene level was used to assess the personal internal PAHs exposure dose. Personal information including occupational history, age, sex, smoking and drinking status was collected by questionnaire.Urinary 1-hydroxypyrene level in coke oven workers [(5.76 +/- 1.04) micro mol/mol Cr] was significantly higher than that in controls [(0.70 +/- 0.32) micro mol/mol Cr]. The rate of CBMN and comet tail moment of lymphocyte in coke oven workers [8.0 per thousand (0.0 per thousand - 30.0 per thousand ) and 2.09 (0.31 - 75.41), respectively] were higher than those in controls [3.5 per thousand (0.0 per thousand - 13.0 per thousand ) and 1.05 (0.11 - 6.63), P0.05]. In controls, the comet moment in smokers was significantly higher than that in non-smokers [1.44 (0.23 - 6.63) vs 0.81 (0.11 - 3.47), P0.05]. According to the length of work, 137 coke oven workers were classified into 3 groups i.e. 0.5 yrs , 16.0 yrs and 22.0 yrs group, and the comet moments were 1.34 (0.31 - 37.84), 2.32 (0.49 - 52.97) and 3.20 (0.45 - 75.41) respectively after adjusting the age, sex, smoking, drinking and level of urinary 1-hydroxy-pyrene. There was a rising tendency along with the increase in length of work.Under present PAHs exposure levels, both comet assay and Cytokinesis-block micronucleus test could detect PAHs-induced genotoxicity in coke oven workers, and comet assay is more suitable to assess the cumulative damage effect on DNA.

To detect the structure and chemical characteristics of the adduct from the reaction of p-benzoquinone (BQ) with deoxyguanoside (dGMP).dGMP and calf thymus DNA were reacted with BQ in buffered solutions with neutral pH, the reaction products were separated and purified by high performance liquid chromatograph (HPLC), and then characterized by UV spectroscopy and mass spectrometry.The reaction of BQ with dGMP yielded two adduct products (Ad(1) and Ad(2) respectively). The characterized results of Ad(1) suggested that BQ reacted at the N-1 and N(2) position of dGMP by losing one H(2)O molecule, the molecular weight of Ad(1) was 437, and the molecular formula was C(16)H(16)O(8)N(5)P. Ad(1) could also be detected from calf thymus DNA reacted with BQ in vitro, which possessed the same elution profile by HPLC analysis. Meanwhile, Ad(2) was detected in the experimental condition. It was proposed that Ad(2) was formed by BQ reacted at the N-9 position of dGMP by losing one molecule of deoxyribose, the molecular weight was 241, and the molecular formula was C(11)H(7)O(2)N(5).The structure of one major adduct from reaction of BQ with DNA is (3'-OH)-1, N(2)-C(6)H(5)CH-2'-deoxyguanosine-5'-monophosphate.

To investigate the relationship between the urinary 1-hydroxypyrene level and cytokinesis-block micronucleus and the olive moment of comet assay in peripheral blood lymphocyte in coke oven workers.One hundred and thirty-three workers from a coke plant and 28 referents without occupational PAH exposure were recruited in this study. Urinary level of 1-hydroxypyrene was measured by alkaline hydrolysis combined with high performance liquid chromatography as an internal exposure dose, and the DNA and chromosomal damage of peripheral blood lymphocyte were evaluated with comet assay and cytokinesis-block micronucleus method. Personal information including occupational history, age, sex, smoking and alcohol drinking, was collected by questionnaire.There existed a good correlationship between the urinary level of 1-hydroxypyrene and frequency of micronuclei per 1 000 binucleated cells or the olive moment of comet assay in the study subjects, after adjusting for sex, age, smoking and alcohol drinking (r0.25, P0.01). One hundred and sixty-one subjects were divided into three groups by their urine 1-hydroxypyrene level (expressed as 0.30 - 2.44, 2.45 - 7.09 and 7.10 - 33.10 micro mol/mol Cr), and the geometric means of their urinary levels of 1-hydroxypyrene were 1.14, 4.32 and 12.49 micro mol/mol Cr, respectively. After adjusting for age, sex, smoking and alcohol drinking by multiple nonparametric analysis of covariance, the median of olive moment of comet assay in the group of 7.10 - 33.10 micro mol/mol Cr was 3.67, significantly higher than that in the groups of 0.30 - 2.44 and 2.45 - 7.09; and the micronuclei frequencies in the groups of 2.45 - 7.09 and 7.10 - 33.10 micro mol/mol Cr were 8.00 per thousand and 7.50 per thousand, respectively, significantly higher than that in the group of 0.30 - 2.44 micro mol/mol Cr (6.00 per thousand ).The comet assay of peripheral blood lymphocyte was more suitable to detect the PAHs-induced early genotoxicity, than the cytokinesis-block micronucleus.