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To explore the associations of 5-year trend and fluctuation in body mass index (BMI) with retinal vascular caliber in a middle-aged and elderly Chinese population.Participants age ≥40 years were recruited in a prospective study. Baseline BMI data were collected in 2008, and the participants were re-examined annually until 2012. Retinal vascular caliber was measured from fundus photographs collected in 2012. BMI trend was calculated as the slope of BMI against the time of examinations. BMI fluctuation was defined as the root mean square error around the regression line of BMI over time (BMI RMSE) and the coefficient of variation of BMI (BMI CV).Rising BMI trend was associated with narrower retinal arteriolar and wider venular calibers in the overall subjects, especially among persons with overweight and obesity (BMI ≥ 25 kg/m(2) , P = 0.004 and 0.033, respectively). Rising BMI trend was also significantly associated with narrower retinal arteriole even in nonobese individuals with BMI25 kg/m(2) (P = 0.017) when eliminating the effects of hypertension and diabetes. Neither BMI RMSE nor BMI CV was statistically associated with retinal vascular caliber (all P0.05).Annual rising trending BMI was associated with retinal microvascular alteration. The results suggest that weight gain probably increases the risk of cardiovascular diseases among middle-aged and elderly people.

To systematically evaluate the environmental exposure information of coke oven workers, we investigated the concentration and size distribution characteristics of the particle matter (PM) in the top working area of coke oven.The aerodynamic particle sizer spectrometer was employed to collect the concentration and size distribution information of PM at a top working area. The PM was divided into PM ≤ 1.0 µm, 1.0 µmPM ≤ 2.5 µm, 2.5 µmPM ≤ 5.0 µm, 5.0 µmPM ≤ 10.0 µm and PM10.0 µm based on their aerodynamic diameters. The number concentration, surface area concentration, and mass concentration were analyzed between different groups. We also conducted the correlation analysis on these parameters among groups.We found the number and surface area concentration of top area particulate was negatively correlated with particle size, but mass concentration curve showed bimodal type with higher point at PM = 1.0 µm and PM = 5.0 µm. The average number concentration of total particulate matter in the top working area was 661.27 number/cm³, surface area concentration was 523.92 µm²/cm³, and mass concentration was 0.12 mg/m³. The most number of particulate matter is not more than 1 µm (PM(1.0)), and its number concentration and surface area concentration accounted for 96.85% and 67.01% of the total particles respectively. In the correlation analysis, different particle size correlated with the total particulate matter differently. And the characteristic parameters of PM2.5 cannot fully reflect the total information of particles.The main particulate matter pollutants in the top working area of coke oven is PM1.0, and it with PM(5.0) can account for a large proportion in the mass concentration of PM. It suggest that PM1.0 and PM(5.0) should be considered for occupational health surveillance on the particulate matter in the top area of coke oven.

With the explosive growth of mobile data demand, there has been an increasing interest in deploying small cells of higher frequency bands underlying the conventional homogeneous macrocell network, which is usually referred to as heterogeneous cellular networks, to significantly boost the overall network capacity. With vast amounts of spectrum available in the millimeter wave (mmWave) band, small cells at mmWave frequencies are able to provide multi-gigabit access data rates, while the wireless backhaul in the mmWave band is emerging as a cost-effective solution to provide high backhaul capacity to connect access points (APs) of the small cells. In order to operate the mobile network optimally, it is necessary to jointly design the radio access and backhaul networks. Meanwhile, direct transmissions between devices should also be considered to improve system performance and enhance the user experience. In this paper, we propose a joint transmission scheduling scheme for the radio access and backhaul of small cells in the mmWave band, termed D2DMAC, where a path selection criterion is designed to enable device-to-device transmissions for performance improvement. In D2DMAC, a concurrent transmission scheduling algorithm is proposed to fully exploit spatial reuse in mmWave networks. Through extensive simulations under various traffic patterns and user deployments, we demonstrate D2DMAC achieves near-optimal performance in some cases, and outperforms other protocols significantly in terms of delay and throughput. Furthermore, we also analyze the impact of path selection on the performance improvement of D2DMAC under different selected parameters., 16 pages, 26 figures, a journal paper, Accepted by IEEE JSAC Special Issue on Recent Advances in Heterogeneous Networks

Diesel engine exhaust (DEE) is a ubiquitous environmental pollutant and is carcinogenic to humans. To seek early and sensitive biomarkers for prediction of adverse health effects, we analysed the components of DEE particles, and examined the genetic and oxidative damages in DEE-exposed workers.101 male diesel engine testing workers who were constantly exposed to DEE and 106 matched controls were enrolled in the present study. The components of DEE were analysed, including fine particulate matter (PM2.5), element carbon (EC), nitrogen dioxide (NO2), sulfur dioxide (SO2) and polycyclic aromatic hydrocarbons (PAHs). Postshift urine samples were collected and analysed for 1-hydroxypyrene (1-OHP), an internal exposure marker for DEE. Levels of DNA strand breaks and oxidised purines, defined as formamidopyrimidine-DNA glycosylase (FPG) sites in leucocytes, were measured by medium throughput Comet assay. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was also used to determine the level of oxidative stress.We found higher levels of PM2.5, EC, NO2, SO2 and PAHs in the diesel engine testing workshop and significantly higher urinary 1-OHP concentrations in exposed subjects (p0.001). Compared with controls, the levels of parameters in normal Comet and FPG-Comet assay were all significantly higher in DEE-exposed workers (p0.001), and in a dose-dependent and time-dependent manner. There were no significant differences between DEE-exposed workers and controls in regard to leucocyte FPG sensitive sites and urinary 8-OHdG levels.These findings suggest that DEE exposure mainly induces DNA damage, which might be used as an early biomarker for risk assessment of DEE exposure.

To explore the carbon black induced effects of lung morphology and pro-inflammation in mice, based on the carbon black aerosol dynamic inhalation exposure model.The carbon black aerosol generated by dynamic inhalation device was imported exposure chamber to mice. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to observe the characters of carbon black. Sixty 9-week-old male BALB/c mice were randomly divided into two control groups, 7 d exposure group and 14 d exposure group. The numbers of four groups of animals were 15, respectively. Mice were exposed to carbon black in the inhalation chamber at (29.33 ± 9.10) mg/m(3) for 6 h/d for continuous exposure 7 d and 14 d, respectively. After 7 d and 14 d exposure, the mice were sacrificed after the last exposure for 24 h. Control mice were killed at 7 d and 14 d. The trachea, lungs, liver, kidneys, and spleen tissues were separated and weighted. Hematoxylin and eosin (HE) staining was used to observe pathological changes of lung by light microscopy. Pulmonary interleukin-8 (IL-8) expression was analyzed by immunohistochemistry. Transmission electron microscopy was used to observe the ultra structure of lung tissue.After 14 d exposure carbon black, the lung coefficient was increased in exposure group compared with control (0.61 ± 0.03 vs 0.79 ± 0.06, t = 6.26, P0.01). The spleen coefficient were higher than control(0.39 ± 0.04 vs 0.51 ± 0.06, t = 4.23, P0.01) . Other organ coefficients were no significant difference between CB group and control group.Histopathology displayed carbon black particles were deposited in the alveoli and lung bronchial wall in 7 d and 14 d groups. The black carbon particles were deposited within the lung tissue of mice in 14 d group. There were cilia damage, serious damage to the alveolar wall, inflammatory cell infiltration and more hyperemia in 14 d group. Immunohistochemistry showed the level of IL-8 in 7 d (0.272 ± 0.011) and 14 d (0.422 ± 0.065) exposure group were higher than control group in 14 d (0.188 ± 0.041) , F = 31.89, P0.01. TEM showed that the lung tissue vision was clear and organelle integrity in the control group. The particles appeared in lung tissue macrophage lysosomes in exposure group, the electron density was consistent with the carbon black particles.The dynamic carbon black particles exposure can affect the lung and spleen coefficient, damage integrity of lung morphology and induce inflammation in mice.

Purpose Structural changes of retinal vasculature, such as altered retinal vascular calibers, are considered as early signs of systemic vascular damage. We examined the associations of 5-year mean level, longitudinal trend, and fluctuation in fasting plasma glucose (FPG) with retinal vascular caliber in people without established diabetes. Methods A prospective study was conducted in a cohort of Chinese people age ≥40 years in Guangzhou, southern China. The FPG was measured at baseline in 2008 and annually until 2012. In 2012, retinal vascular caliber was assessed using standard fundus photographs and validated software. A total of 3645 baseline nondiabetic participants with baseline and follow-up data on FPG for 3 or more visits was included for statistical analysis. The associations of retinal vascular caliber with 5-year mean FPG level, longitudinal FPG trend (slope of linear regression-FPG), and fluctuation (standard deviation and root mean square error of FPG) were analyzed using multivariable linear regression analyses. Results Multivariate regression models adjusted for baseline FPG and other potential confounders showed that a 10% annual increase in FPG was associated independently with a 2.65-μm narrowing in retinal arterioles (P = 0.008) and a 3.47-μm widening in venules (P = 0. 0.004). Associations with mean FPG level and fluctuation were not statistically significant. Conclusions Annual rising trend in FPG, but not its mean level or fluctuation, is associated with altered retinal vasculature in nondiabetic people.

With vast amounts of spectrum available in the millimeter wave (mmWave) band, small cells at mmWave frequencies densely deployed underlying the conventional homogeneous macrocell network have gained considerable interest from academia, industry, and standards bodies. Due to high propagation loss at higher frequencies, mmWave communications are inherently directional, and concurrent transmissions (spatial reuse) under low inter-link interference can be enabled to significantly improve network capacity. On the other hand, mmWave links are easily blocked by obstacles such as human body and furniture. In this paper, we develop a Multi-Hop Relaying Transmission scheme, termed as MHRT, to steer blocked flows around obstacles by establishing multi-hop relay paths. InMHRT, a relay path selection algorithmis proposed to establish relay paths for blocked flows for better use of concurrent transmissions. After relay path selection, we use a multi-hop transmission scheduling algorithm to compute near-optimal schedules by fully exploiting the spatial reuse. Through extensive simulations under various traffic patterns and channel conditions, we demonstrate MHRT achieves superior performance in terms of network throughput and connection robustness compared with other existing protocols, especially under serious blockage conditions. The performance of MHRT with different hop limitations is also simulated and analyzed for a better choice of themaximum hop number in practice., Comment: 11 pages, 12 figures, to appear in Journal of communications and networks

Theoretically, a haplotype has a higher level of heterozygosity than individual single nucleotide polymorphism (SNP) and the association study based on the haplotype may have an increased power for detecting disease associations compared with SNP-based analysis. In this study, we investigated the effects of four haplotype-tagging SNPs (htSNP) and the inferred haplotype pairs of the X-ray cross-complementing group 1 (XRCC1) gene on chromosome damage detected by the cytokinesis-block micronucleus assay. The study included 141 coke-oven workers with exposure to a high level of polycyclic aromatic hydrocarbons and 66 nonexposed controls. The frequencies of total MN and MNed cells were borderline associated with the Arg194Trp polymorphism (P = 0.053 and P = 0.050, respectively) but not associated with the Arg280His, Arg399Gln and Gln632Gln polymorphisms among coke-oven workers. Five haplotypes, including CGGG, TGGG, CAGG, CGAG, and CGGA, were inferred based on the four htSNPs of XRCC1 gene. The haplotype CGGG was associated with the decreased frequencies of total MN and MNed cells, and the haplotypes TGGG and CGAG were associated with the increased frequencies of total MN and MNed cells with adjustment for covariates among coke-oven workers. This study showed that the haplotypes derived from htSNPs in the XRCC1 gene were more likely than single SNPs to correlate with the polycyclic aromatic hydrocarbon–induced chromosome damage among coke-oven workers.

In order to investigate the ratcheting behavior of T225NG alloy, a series of ratcheting tests under uniaxial long-cyclic stressing were performed. The results show that the ratcheting strain of this alloy can get into shakedown after tens (or hundreds) of thousand cycles. After the ratcheting strain is saturated under the condition that stress amplitude is half of peak stress, it will bring about subsequent fatigue failure, and relationship between fatigue life and one of peak stress and saturated ratcheting (SR) strain meets power law. As the alloy is under stress jiggling with stress amplitude that is 1%–2.5% of peak stress, the ratcheting strain still become remarkable and goes into shakedown after several hundreds of thousand cycles but there exists little accessional strain caused by creep effect. It is notable that, when the peak stress is 85%–100% of yield stress, the long cyclic stressing will lead SR strain to be from 1.4% to 2.5% even if the initial ratio of ratcheting strain is zero. Based on ratcheting threshold property of peak stress and monotonicity of relationship between the peak stress and SR strain, a saturated ratcheting model (SRM) is developed to predict SR strain and to estimate saturated creep strain also. In addition, the classes of ratcheting evolutions of metals are discussed.

Exploring the associations between genetic polymorphisms of metabolic enzymes and susceptibility to polycyclic aromatic hydrocarbon (PAH)-induced chromosomal damage is of great significance for understanding PAH carcinogenesis. Cytochrome P450, glutathione S-transferase, microsomal epoxide hydrolase, NAD(P)H:quinone oxidoreductase, and N-acetyltransferase are PAH-metabolizing enzymes. In this study, we genotyped for the polymorphisms of these genes and assessed their effects on cytokinesis-block micronucleus (CBMN) frequencies in peripheral blood lymphocytes among 141 coke-oven workers and 66 non-coke-oven worker controls. The geometric means of urinary 1-hydroxypyrene levels in coke-oven workers and the controls were 12.0 and 0.7 micromol/mol creatinine, respectively (P0.01). The CBMN frequency (number of micronuclei per 1,000 binucleated lymphocytes) was significantly higher in coke-oven workers (9.5 +/- 6.6 per thousand) than in the controls (4.0 +/- 3.6 per thousand; P0.01). Among the coke-oven workers, age was positively associated with CBMN frequency; the mEH His113 variant genotype exhibited significantly lower CBMN frequency (8.5 +/- 6.5 per thousand) than did the Tyr113/Tyr113 genotype (11.3 +/- 6.4 per thousand; P0.01); the low mEH activity phenotype exhibited a lower CBMN frequency (8.6 +/- 6.8 per thousand) than did the high mEH activity phenotype (13.2 +/- 6.7 per thousand; P = 0.01); the GSTP1 Val105/Val105 genotype exhibited a higher CBMN frequency (15.0 +/- 5.8 per thousand) than did the GSTP1 Ile105/Ile105 or Ile105/Val105 genotypes (9.3 +/- 6.5 per thousand; P0.01); the joint effect of high mEH activity phenotype and GSTM1 null genotype on CBMN frequencies was also found. Gene-environment interactions between occupational PAH exposure and polymorphisms of mEH and/or GSTM1 were also evident. These results indicate that the mEH, GSTP1, and GSTM1 polymorphisms may play a role in sensitivity or genetic susceptibility to the genotoxic effects of PAH exposure in the coke-oven workers.

A wide variety of base damages and single-strand breaks formed by reactive oxygen species during metabolic activation of polycyclic aromatic hydrocarbons (PAHs) have been recognized to be involved in PAH carcinogenesis. In this study, alkaline comet assay was used to detect the DNA damage in peripheral blood lymphocytes among 143 coke-oven workers and 50 non-coke-oven workers, and the effects of genetic polymorphisms of XRCC1 and ERCC2 genes on DNA damage were evaluated. The olive tail moment was significantly higher in coke-oven workers than in non-coke-oven workers (2.6, 95% CI=2.1-3.3 versus 1.0, 95% CI=0.8-1.2, p0.01), and significant correlation between ln-transformed urinary 1-OHP and ln-transformed olive tail moment was found in total population (n=193, Pearson's r=0.393, p0.001) and in coke-oven workers (n=143, Pearson's r=0.224, p=0.007). The olive tail moment was significantly higher in coke-oven workers with GA genotype of G27466A polymorphism of XRCC1 than those with GG genotype (4.6, 95% CI=2.5-8.7 versus 2.4, 95% CI=1.9-2.9, p0.01 with adjustment for covariates). No significant associations between C26304T, G28152A and G36189A polymorphisms of XRCC1 and G23591A and A35931C polymorphisms of ERCC2 and olive tail moment were found in both groups. The study showed that the alkaline comet assay is a suitable biomarker in the detection of DNA damage among coke-oven workers and it suggested that the A allele of G27466A polymorphism of XRCC1 may be associated with decreased DNA repair capacity toward PAH-induced base damage and strand breaks.

Trichloroethylene (TCE)-induced severe generalized dermatitis (SGD) is considered to be a contact allergic disease and is dependent on a cell-mediated immune response. Little is known about its pathogenesis. Several lines of evidence suggest that tumour necrosis factor (TNF) and interleukin 4 (IL-4) are involved in the immunological and inflammatory reactions. To investigate the relation between polymorphisms of TNF and the IL-4 gene and the risk of TCE-induced SGD, a case-control study was conducted consisting of 111 patients diagnosed with SGD and 152 TCE-exposed workers without SGD. Polymerase chain reaction-restriction fragment length polymorphism was used to detect the polymorphisms of TNF-alpha (G-238A, G-308A), TNF-beta (intron 1) and IL-4 (C-590T). Logistic regression was applied to calculate the odds ratios (OR) and 95% confidence intervals. The results reveal that the frequency of TNF alpha-308 wild allele in cases was significantly higher than that in control subjects (p=0.049). Individuals with a heterozygous genotype of TNF alpha-308 were associated with the decreased risk of TCE-induced SGD relative to the homozygous genotype (OR=0.398, 95% CI=0.164-0.967). No significant differences in the allele and genotype frequencies could be demonstrated at any other polymorphic loci among both groups. The finding of a possible contribution of a TNF-alpha genetic polymorphism is a primary result because the pathogenesis of TCE-induced SGD is complex and likely to involve the interaction of a number of genes. A further study should be conducted to illustrate the influence of a link between certain relevant alleles in the assessment of genetic susceptibility

Rationale: Recent epidemiological studies show that Diesel Engine Exhaust (DEE) exposure is associated with lung cancer, however the mechanism by which this occurs is not well understood. The goal of this study was to assess the transcriptomic alterations in the nasal epithelium of DEE exposed workers from factories where diesel engines are utilized. Methods: Nasal epithelium brushings were obtained from 41 subjects who work in a factory with DEE exposure, and 38 comparable control subjects who work in factories without any DEE exposure. The median Elemental Carbon (EC) levels of exposed individuals was 60.7μg/m3, with a range of 17.2-105.4 μg/m3, respectively. RNA was isolated from nasal epithelial cells, and profiled for gene expression using Affymetrix microarrays. Linear modeling was used to detect differential expression between DEE exposure and controls. Pathway enrichment in differentially expressed genes was assessed using GO Biological Process and KEGG terms via EnrichR. Results: We found 234 genes that were differentially expressed between samples derived from DEE exposed participants versus controls at FDR q < 0.25. Within this set of genes, we observed a higher expression of genes involved in oxidative stress response, as well as cell proliferation, cellular transcription, and regulation of apoptosis. In addition, we found that genes involved in ion transport, such as CFTR, were expressed at lower levels in DEE exposed samples. Conclusions: Chronic DEE exposure associates with changes in the airway transcriptome, with increased stress response as a major effect of DEE exposure. The transcriptomic alterations we identified may help provide insight into the underlying mechanisms of DEE carcinogenicity. Citation Format: Eduard I. Drizik, Sean Corbett, Roel Vermeulen, Yufei Dai, Wei Hu, Marc Lenburg, Dianzhi Ren, Huawei Duan, Yong Niu, Jun Xu, Wei Fu, Kees Meliefste, Baosen Zhou, JuFang Yang, Meng Ye, Xiaowei Jia, Tao Meng, Ping Bin, Yuxin Zheng, Debra Silverman, Nathaniel Rothman, Avrum Spira, Qing Lan. Impact of diesel engine exhaust exposure on the airway transcriptome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4256. doi:10.1158/1538-7445.AM2017-4256

Fast and nondestructive detection of early decay caused by fungal infection in citrus fruit was a challenging task for the citrus industry during the postharvest fruit processing. In general, workers relied on the ultraviolet induction fluorescence technique to detect and remove the decayed citrus fruits in fruit packing houses. However, this operation was harmful for human health, and was also very inefficient. In this study, navel oranges were used as research object. A novel method combining with hyperspectral imaging technology in the wavelength region between 400 and 1100 nm wavelength was proposed to solve this problem. First, normalization approaches were applied to decrease the variation of spectral reflectance intensity due to natural curvature of navel orange surface. Then, the spectral data of regions of interest (ROIs) from normal and decayed tissues was analyzed by principal component analysis (PCA) for investigating the performance of visible and near infrared (Vis-NIR) hyperspectral data to discriminate these two kinds of tissues. Next, six characteristic wavelength images were obtained by analyzing the loadings of the first principal component (PC1). And, a multispectral image was established by using the corrected six characteristic wavelength images. On basis of the multispectral image, pseudo-color image processing with intensity slicing was utilized to produce a two-dimensional color image with clear contrast between decayed and normal tissues. Finally, an image segmentation algorithm by combining the pseudo-color processing method and a global threshold method was proposed for fast identification of decayed navel oranges. For 240 independent samples, the success rates were 100 and 97.5% for decayed navel oranges infected by Penicillium digitatum and normal navel oranges, respectively. In particular, the proposed algorithm was also applied to detect the decayed navel oranges infected by Penicillium italicum (samples not used for the development of algorithm) and obtained a 91.7% identification accuracy, indicating a well generalization ability and actual application value of the proposed algorithm.

Background Although major concerns exist regarding the potential consequences of human exposures to nanoscale carbon black (CB) particles, limited human toxicological data is currently available. The purpose of this study was to evaluate if nanoscale CB particles could be responsible, at least partially, for the altered lung function and inflammation observed in CB workers exposed to nanoscale CB particles. Methods Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Brunauer-Emmett-Teller were used to characterize CB. Eighty-one CB-exposed male workers and 104 non-exposed male workers were recruited. The pulmonary function test was performed and pro-inflammatory cytokines were evaluated. To further assess the deposition and pulmonary damage induced by CB nanoparticles, male BALB/c mice were exposed to CB for 6 hours per day for 7 or 14 days. The deposition of CB and the pathological changes of the lung tissue in mice were evaluated by paraffin sections and TEM. The cytokines levels in serum and lung tissue of mice were evaluated by ELISA and immunohistochemical staining (IHC). Results SEM and TEM images showed that the CB particles were 30 to 50 nm in size. In the CB workplace, the concentration of CB was 14.90 mg/m3. Among these CB particles, 50.77% were less than 0.523 micrometer, and 99.55% were less than 2.5 micrometer in aerodynamic diameter. The reduction of lung function parameters including FEV1%, FEV/FVC, MMF%, and PEF% in CB workers was observed, and the IL-1β, IL-6, IL-8, MIP-1beta, and TNF- alpha had 2.86-, 6.85-, 1.49-, 3.35-, and 4.87-folds increase in serum of CB workers, respectively. In mice exposed to the aerosol CB, particles were deposited in the lung. The alveolar wall thickened and a large amount of inflammatory cells were observed in lung tissues after CB exposure. IL-6 and IL-8 levels were increased in both serum and lung homogenate. Conclusions The data strongly suggests that nanoscale CB particles could be responsible for the lung function reduction and pro-inflammatory cytokines secretion in CB workers. These results, therefore, provide the first evidence of a link between human exposure to CB and long-term pulmonary effects. Electronic supplementary material The online version of this article (doi:10.1186/s12989-014-0073-1) contains supplementary material, which is available to authorized users.

The International Agency for Research on Cancer has recently reclassified diesel engine exhaust (DEE) as a Group 1 carcinogen. Micronucleus (MN), nucleoplasmic bridge (NPB), and nuclear bud (NBUD) frequencies in peripheral blood lymphocytes (PBLs) are associated with cancer risk. However, the impact of DEE exposure on MN frequency has not been thoroughly elucidated due to mixed exposure and its impact on NPB and NBUD frequencies has never been explored in humans. We recruited 117 diesel engine testing workers with exclusive exposure to DEE and 112 non-DEE-exposed workers, and then we measured urinary levels of 4 mono-hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) using highperformance liquid chromatography-mass spectrometry as well as MN, NPB, and NBUD frequencies in PBLs using cytokinesis-block MN assay. The DEE-exposed workers exhibited significantly higher MN, NPB, and NBUD frequencies than the non-DEE-exposed workers (P < 0.05). Among all study subjects, increasing levels of all 4 urinary OH-PAHs, on both quartile and continuous scales, were associated with increased MN, NPB, and NBUD frequencies (all P < 0.05). When the associations were analyzed separately in DEE-exposed and non-DEE-exposed workers, we found that the association between increasing quartiles of urinary 9-hydroxyphenanthrene (9-OHPh) and MN frequencies persisted in DEE-exposed workers (P ¼ 0.001). The percent of MN frequencies increased, on average, by 23.99% (95% confidential interval, 9.64–39.93) per 1-unit increase in ln-transformed 9-OHPh. Our results clearly show that exposure to DEE can induce increases in MN, NPB, and NBUD frequencies in PBLs and suggest that DEE exposure level is associated with MN frequencies.

Different from the current studies on the impulsive rendezvous which are mainly normal propellant-optimal or time-optimal designs, the safety-optimal impulsive rendezvous with consideration of practical trajectory uncertainties is investigated in this paper. An optimization model for safety-optimal rendezvous is established based on the Clohessy-Wiltshire (C-W) equations, which employs one new, recently proposed quantitative performance index of the rendezvous trajectory safety as the objective function. A real-coded genetic algorithm is adopted to locate the optimal solution. The safety index and the optimization approach are tested by several rendezvous problems with different numbers of impulses and different approach directions. The practical application value of the safety-optimal rendezvous trajectory is demonstrated by comparing with the traditional propellant-optimal and time-optimal rendezvous trajectories.

China SONG telescope would achieve the goal for long time continuous, uninterrupted, full automatic observation and works in the diffraction limit condition with high tracking precision and reliability, which puts forward a serious challenge to the tracking control system. This paper explores one sliding mode control algorithm to improve the performance of China SONG telescope tracking system. The results show that the algorithm can get higher precision, which has high exploration significance for the telescope tracking system.

This paper deals with the problem of nonfragile H ∞ filtering for a class of discrete-time nonlinear systems that are represented by a Takagi-Sugeno (T-S) fuzzy model. The main result given here concerns its nonfragile H ∞ filter design based on a relaxed approach in which both Finsler's Lemma and delayed nonquadratic Lyapunov function are used. New filter design conditions are proposed in term of linear matrix inequalities (LMIs) which allow outperforming previous results found in the literature. Finally, an example is given to demonstrate the efficiency of the proposed approach.

The aim of this study was to investigate the use of the lesion-specific endonucleases-modified comet assay for analysis of DNA oxidation in cell lines.DNA breaks and oxidative damage were evaluated by normal alkaline and formamidopyrimidine-DNA-glycosylase (FPG) modified comet assays. Cytotoxicity were assessed by MTT method. The human bronchial epithelial cell (16HBE) were treated with benzo (a) pyrene (B(a)P), methyl methanesulfonate (MMS), colchicine (COL) and vincristine (VCR) respectively, and the dose is 20 µmol/L, 25 mg/ml, 5 mg/L and 0.5 mg/L for 24 h, respectively. Oxidative damage was also detected by levels of reactive oxygen species in treated cells.Four genotoxicants give higher cytotoxicity and no significant changes on parameters of comet assay treated by enzyme buffer. Cell survival rate were (59.69 ± 2.60) %, (54.33 ± 2.81) %, (53.11 ± 4.00) %, (51.43 ± 3.92) % in four groups, respectively. There was the direct DNA damage induced by test genotoxicants presented by tail length, Olive tail moment (TM) and tail DNA (%) in the comet assay. The presence of FPG in the assays increased DNA migration in treated groups when compared to those without it, and the difference was statistically significant which indicated that the clastogen and aneugen could induce oxidative damage in DNA strand. In the three parameters, the Olive TM was changed most obviously after genotoxicants treatment. In the contrast group, the Olive TM of B(a) P,MMS, COL,VCR in the contrast groups were 22.99 ± 17.33, 31.65 ± 18.86, 19.86 ± 9.56 and 17.02 ± 9.39, respectively, after dealing with the FPG, the Olive TM were 34.50 ± 17.29, 43.80 ± 10.06, 33.10 ± 12.38, 28.60 ± 10.53, increased by 58.94%, 38.48%, 66.86% and 68.21%, respectively (t value was 3.91, 3.89, 6.66 and 3.87, respectively, and all P0.05), and the correlation between Olive TM and reactive oxygen species was better than other parameters (r = 0.77, P0.05).This study indicates that FPG-comet assay appears more specific for detecting oxidative DNA damage induced by genotoxicants exposure, and the application of comet assay will be expanded. The endonuclease modified comet assay will be used widely in the toxicology and molecular epidemiology study.

Formaldehyde (FA) is a well-known irritant, and it is suggested to increase the risk of immune diseases and cancer. The present study aimed to evaluate the distribution of major lymphocyte subsets and cytokine expression profiles in the peripheral blood of FA-exposed workers. A total of 118 FA-exposed workers and 79 controls were enrolled in the study. High performance liquid chromatography, flow cytometry, and cytometric bead array were used to analyze FA in air sample and formic acid in urine, blood lymphocyte subpopulations, and serum cytokines, respectively. The FA-exposed workers were divided into low and high exposure groups according to their exposure levels. The results showed that both the low and high FA-exposed groups had a significant increase of formic acid in urine when compared to the controls. Both the low and high exposure groups had a significant increase in the percentage of B cells (CD19+) compared to the control group (p

Puralpha, a single-stranded DNA binding protein, recognizes a PUR element (GGN repeat). We have reported that Puralpha binds to a single-stranded oligonucleotide probe containing the cAMP response element (CRE) of rat somatostatin gene using a gel mobility shift assay. Here, we showed that Puralpha binds to the probe only in the presence of a PUR element by a more detailed characterization. We also examined the effects of Puralpha on the enhancer activity of the somatostatin CRE in PC12 cells using the reporter gene assay. Transfected Puralpha suppressed the CRE enhancer activity stimulated by forskolin (which increases intracellular cAMP), but suppression was not observed when the PUR element was deleted. The neurite extension induced by forskolin was inhibited by the transfection of Puralpha, but that by NGF was not suppressed. The c-fos mRNA induced by forskolin, but not by NGF, was also suppressed by Puralpha transfection. These results indicate that Puralpha suppresses the biological activities induced by forskolin, but not by NGF, in PC12 cells and that Puralpha could interfere with a cAMP-CRE signal pathway.

Pur alpha is a single stranded DNA-binding protein and binds to a consensus sequence (GGN)n. We have reported that the DNA-binding activity of a single stranded cyclic AMP response element-binding protein (ssCRE-BP) is suppressed in cerebellum treated chronically with morphine, ssCRE-BP is identical to Pur alpha and the DNA binding activity of Pur alpha is markedly enhanced by a heat stable activator in the nuclear extract. In this report, we purified this activator. The amino acid composition and partial amino acid sequence were determined to be identical to those of calmodulin (CaM), which enhanced the binding of GST-Pur alpha to various PUR elements in the 5' non-coding regions of the neuropeptide Y, myelin basic protein and nicotinic Ach receptor beta 4 subunit genes. The data suggest a novel gene expression pathway mediated by Ca/CaM-Pur alpha which may regulate a variety of genes in addition to those regulated through the CREB pathway.

ssCRE-BP/Pur alpha is a single stranded DNA-binding protein and may be involved in gene replication and transcription and in the development of morphine dependence. We found a ssCRE-BP/Pur alpha (45 kDa) in rat lung that was larger than those (40 kDa) identified in rat and mouse brains and mouse lung. Immunohistochemistry showed that ssCRE-BP/Pur alpha is primarily distributed in the lung epithelium. As allergic inflammation induces various gene expressions, we investigated the changes of Pur alpha during airway inflammation. Ovalbumin-sensitized rats were used for inducing allergic airway inflammation. The expression and DNA-binding activity of 45-kDa ssCRE-BP/Pur alpha were significantly increased in the sensitized rat lungs 24 hr after antigen challenge, but not in those of rats nonsensitized or sensitized with ovalbumin and challenged with saline. Immunohistochemistry and in situ hybridization demonstrated that the vascular endothelial cells and numerous infiltrated eosinophils around the airways were stained with anti-Pur alpha antibody. These data suggest that rat lung and the eosinophils contain a 45-kDa ssCRE-BP/Pur alpha that is increased when airway inflammation occurs.

Delamination was a critical failure to the microelectronics products, and it was introduced mainly by two factors: strong interface stress or poor interface adhesion. In this paper a tracking experiment confirmed the delamination between die attach and leadframe flag in a SOIC device, which occurred during wire bonding. Results of actual experiments and FEA found during the process flow, there were changes of structure profile as well as von Mises stress at the edge of die attach layer. This alternating stress was introduced by temperature cycling during D/A curing, wire bonding and following cooling; and resulted into the delamination at the interface, whose occurrence could be reduced when a higher peak temperature of D/A curing, a lower temperature of wire bonding, a thicker BLT or a CTE-lower die attach was applied. With a balance between delamination and other items, a final solution was proposed and got perfect results.

To compare the determination ability of four in vitro cytotoxicity assays for acute toxicity of diesel exhaust particulate (DEP) extracts.The cell viability of cultured 16HBE cells was measured by the MTT assay, the neutral red assay, the lactate dehydrogenase (LDH) leakage assay and the determination of total protein content after 12, 24 and 48h of being exposed to DEP extracts at different concentrations of 5, 10, 20, 40, 80 and 160 microg/ml.For measuring the acute cytotoxicity, the MTT assay was more delicate than the other three methods after 12h exposure. The sensitivity of both the MTT assay and the neutral red assay increased as the exposure time extended. The cell viability at each dosage decreased significantly after being exposed to DEP extracts for 24h compared to the control group (P0.05). When using the LDH assay, the cell viability reduced after 24h exposure to DEP extracts, but changed no more as time prolonged. Only the cell viabilities of the groups exposed to the high dosages of DEP extracts were observed with significant reduction by the protein assay after 12h and 24h exposure respectively. The cell viabilities measured by the same method at all dosages decreased after 48h exposure.The results of the four cytotoxicity assays showed differences in the present study. The MTT assay and the neutral red assay are more sensitive in detecting the adverse effect to 16HBE cells done by DEP extracts compared to the LDH assay and the protein assay. Taken the indicants of each toxicity assay into account, the DEP extracts may have major adverse effects on the functions of the organelles in 16HBE cells, such as mitochondria and lysosomes, however little influence to the cell anchorage dependence and the cell membrane damage.

Global hypomethylation, gene-specific methylation, and genome instability are common events in tumorigenesis. To date, few studies have examined the aberrant DNA methylation patterns in coke oven workers, who are highly at risk of lung cancer by occupational exposure to polycyclic aromatic hydrocarbons (PAHs). We recruited 82 PAH-exposed workers and 62 unexposed controls, assessed exposure levels by urinary 1-hydroxypyrene, and measured genetic damages by comet assay, bleomycin sensitivity, and micronucleus assay. The PAHs in coke oven emissions (COE) were estimated based on toxic equivalency factors. We used bisulfite-PCR pyrosequencing to quantitate DNA methylation in long interspersed nuclear element-1 (LINE-1) and O6-methylguanine-DNA methyltransferase (MGMT). Further, the methylation alteration was also investigated in COE-treated human bronchial epithelial (16HBE) cells. We found there are higher levels of PAHs in COE. Among PAH-exposed workers, LINE-1 and MGMT methylation levels (with CpG site specificity) were significantly lowered. LINE-1, MGMT, and its hot CpG site-specific methylation were negatively correlated with urinary 1-hydroxypyrene levels (r = −0.329, p < 0.001; r = −0.164, p = 0.049 and r = −0.176, p = 0.034, respectively). In addition, LINE-1 methylation was inversely associated with comet tail moment and micronucleus frequency, and a significant increase of micronucleus in low MGMT methylation group. In vitro study revealed that treatment of COE in 16HBE cells resulted in higher production of BPDE-DNA adducts, LINE-1 hypomethylation, hypomethylation, and suppression of MGMT expression. These findings suggest hypomethylation of LINE-1 and MGMT promoter could be used as markers for PAHs exposure and merit further investigation.

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 investigate the association between the exposure of trichloroethylene (TCE) and chromosomal damage of peripheral lymphocyte of workers.Ninety-one workers exposed to TCE and 59 controls were recruited. Occupational history, age, sex, smoking and alcohol using status of all subjects were collected by questionnaire. Trichloroacetic acid (TCA) in urine was detected as biomarkers of exposure. Micronucleus, nucleoplasmic bridges and nuclear buds in the smear of peripheral blood lymphocytes were counted as indicators of chromosomal damage in terms of cytokinesis-block micronucleus (CBMN) test.The distributions of age, gender, smoking and alcohol consumption were not significantly different between TCE exposed workers and controls. TCA levels in TCE exposed workers were significantly higher than those in controls (57.5 versus 0.9 mg/L, P0.01). No statistically significant difference was observed between the frequencies of micronucleus or nucleoplasmic bridges in TCE exposed workers and controls. Frequencies of nuclear buds in TCE exposed workers were [(1.6 +/- 1.0)%], which were significantly higher (P = 0. 05) than those of controls [(1.2 +/- 0.8) per hundred]. The increase of nuclear buds was most pronounced in the workers with higher TCA (or = 50.0 mg/ L) or longer occupational history (or = 1.8 years). There was a significantly higher frequency of micronucleus [(1.8 +/- 0.9) per hundred] in the workers with a higher TCA level (or = 50.0 mg/L) than the controls [(1.4 +/- 0.7) per hundred, P = 0.05]. No effect of age, gender, smoking and alcohol using on frequencies of micronucleus, nucleoplasmic bridges or nuclear buds was found.TCE exposure could induce some chromosomal damage on occupational exposed workers and nuclear buds might be an effective biomarker for TCE exposure.

The modern large telescope is endowed with advanced imaging systems and active optics, resulting in very high peak angular resolution. The drive systems for the telescope must consequently be able to guarantee a tracking accuracy better than the telescope angular resolution, in spite of unbalanced and sudden loads such as wind gusts and in spite of a structure that, because of its size, can not be infinitely stiff, which puts forward a great challenge to the telescope’ drive system. Modern telescope’s drive system is complicated, which performance and reliability directly affect the telescope tracking performance and reliability. Redundant technology is one of the effective ways to improve the security of the system. This paper will introduce one redundant synchronous control method for direct drive torque motor of large diameter telescope drive system, which can effectively improve the telescope drive system tracking precision and improve the reliability, stability and anti-jamming ability.

Direct drive technology is the key to solute future 30-m and larger telescope motion system to guarantee a very high tracking accuracy, in spite of unbalanced and sudden loads such as wind gusts and in spite of a structure that, because of its size, can not be infinitely stiff. However, this requires the design and realization of unusually large torque motor that the torque slew rate must be extremely steep too. A conventional torque motor design appears inadequate. This paper explores one redundant unit permanent magnet synchronous motor and its simulation bed for 30-m class telescope. Because its drive system is one high integrated electromechanical system, one complexly electromechanical design method is adopted to improve the efficiency, reliability and quality of the system during the design and manufacture circle. This paper discusses the design and control of the precise tracking simulation bed in detail.

The aim of the present study was to investigate the effect of glucagon-like peptide-1 (GLP-1) on palmitate-induced apoptosis of human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. HUVECs were cultured in vitro, and then treated by palmitate to induce apoptosis. Meanwhile, GLP-1 was added to explore its effect. After 24 h of the treatments, Caspase-3 activity and DNA fragmentation were measured using ELISA kits. Phospho-p38 mitogen-activated protein kinase (p-p38 MAPK) expression was detected by Western blot. The results showed that incubating HUVECs with 0.125 mmol/L GLP-1 increased Caspase-3 activity and DNA fragmentation. GLP-1 significantly inhibited palmitate-induced increases of Caspase-3 activity and DNA fragmentation in a concentration-dependent manner. Moreover, GLP-1 inhibited the up-regulation of p-p38 MAPK expression induced by palmitate in HUVECs. These results suggest GLP-1 protects HUVECs against lipo-apoptosis, and this effect may be mediated through inhibiting p38 MAPK pathway.

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.

This paper presents a high-throughput and routing complexity reduced decoder for Quasi-Cyclic Low-Density Parity-Check (QC-LDPC) codes in the high rate wireless personal area network applications (WPAN). Our selected code is the rate-1/2 QC-LDPC code in IEEE P802.11ad/D1.0. A new decoder architecture is proposed. The message paths between variable nodes and check nodes are constructed by a fixed wire network. Compared to the fully parallel architecture, routing complexity of the new architecture is reduced greatly. The decoder is implemented using FPGA, and a data rate of 1.21Gbps can be achieved in the air.

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.

Occupational trichloroethylene (TCE) exposure could induce generalized skin hypersensitivity reactions complicated with severe liver dysfunctions. Active extracellular matrix degradation and remodeling are involved in the skin hypersensitivity reaction induced by chemical exposure. In the present study, we have compared the effects of in vitro exposure to trichloroethanol (TCOH) and trichloroacetic acid (TCA) of a keratinocyte cell line (HaCaT). The modulation of matrix metalloproteinases (MMPs) was selected as marker of sensitization. HaCaT cells were treated with different concentrations of TCOH or TCA up to 6days. The gelatinolyic activities of MMP-2 and MMP-9 were detected by gelatin-zymography. MMP-2, tissue inhibitor of metalloproteinase (TIMP)-2, MMP-9 and TIMP-1 mRNAs were analyzed by real-time PCR and MMP-9 and TIMP-1 proteins were tested by Western blotting. A dose-effect relationship between TCOH treatment and MMP-9 activity, mRNA and protein expression levels was found in HaCaT cells. TCOH also induced up-regulation of TIMP-1 mRNA and protein. We found no such effects in HaCaT cells treated with TCA. Moreover, previously published literatures on patch tests suggested that TCOH could induce moderately positive reactions at low concentrations in hypersensitivity patients caused by occupational TCE exposure. In summary, these observations indicated that TCOH might play an important role in TCE-induced skin hypersensitivity.

To observe the capability of enamel surface resisting juice drinks erosion and the remineralization process of etched enamel after topical fluoride application on young permanent teeth enamel.The change of surface microhardness(SMH) of young permanent teeth enamel fluoride which was immersed in orange juice in advance and then applied on its etched part was evaluated.The change of SMH of young permanent teeth enamel treated by 0.1%NaF solution and fluoride toothpaste in advance and then immersed by juice drinks was observed. The change of enamel SMH was measured by a Leitzs microhardness tester. The morphological change of enamel surface was observed under scanning electron microscope (SEM). The change of calcium and phosphate contents in juice drinks before and after enamel immersion was analyzed by Roche biochemical analyzer. One-way ANOVA was performed using SPSS 15.0 software package.Juice drinks led to the dissolution of calcium and phosphate in young permanent teeth enamel while the SMH of enamel decreased. The SMH of young permanent teeth enamels immersed in orange juice and then topical application of fluoride increased significantly (Plt;0.05). But for those young permanent teeth enamels treated with fluoride or fluorin enhanced toothpaste, the dissolution of calcium and phosphate and the SMH decreased significantly after juice drinks immersion(P0.05). The variable degree of etching and remineralization of the enamel either treated by juice drinks or by fluoride in each experimental group was found by SEM.Enamel demineralization can be caused by juices drinks. Topical fluoride treatment on enamel can not only enhance enamel's resistance to the acid etch caused by soft drinks but also promote the remineralization of enamel immersed by beverages. Supported by Excellent Middle-Aged Science Foundation of Shanghai Jiao Tong University School of Medicine(Grant No.040407).

To investigate the role of myelin protein zero (P(0)) in 2,5-hexanedione (2,5-HD)-induced peripheral nerve injury, and the protective effect of Ginkgo biloba extract (Egb761) on 2,5-HD-induced toxic peripheral neuropathy.After 4 weeks of treatment with 2,5-HD at different doses (50, 100, 200, 400 mg/kg) in rats, changes in the levels of P(0) in rat sciatic nerves was investigated, and the effect of Egb761 on 2,5-HD-induced toxic peripheral neuropathy was studied.The blood-nerve barrier (BNB) permeability of the sciatic nerve increased, and the expression of P(0) mRNA and P(0) protein decreased in a dose-dependent manner after treatment with 2,5-HD for 4 weeks. Pretreatment with Egb761 protected against BNB interruption, and inhibited P(0) mRNA and protein reduction during 2,5-HD treatment. Pretreatment with Egb761 significantly reduced loss of body weight (P0.01) and mitigated gait abnormalities (2.85±0.22) induced by 400 mg/kg 2,5-HD (P0.01). It also reduced the signs of neurotoxicity induced by 2,5-HD.2,5-HD inhibited the expression of P(0) in a dose-dependent manner, and this may be an important mechanism by which toxic peripheral neuropathy is induced by 2,5-HD. Egb761 has a protective effect against 2,5-HD-induced peripheral neurotoxicity in rats.

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 establish a HPLC-MS/MS method for the simultaneous determination of 4 monohydroxy metabolites of polycyclic aromatic hydrocarbons (PAHs) in urine, including 1-naphthol, 2-naphthol, 3-phenanthrol and 1-pyrenol).After being treated by enzymatic hydrolysis, urine samples were purified by liquid-liquid extraction, evaporated under nitrogen to constant volume and examined by HPLC-MS/MS. Target compounds were quantified by internal standard calibration curve.The reproducibility and precision were improved by internal standard calibration. The recovery of four target compounds were in the range of 89.7%-103.0%. The precision of intra- and inter-batch was 1.0%-4.2% and 1.8%-5.8% respectively. The limits of quantification was 0.2 microg/L for 1-naphthol, 2-naphthol and 1-pyrenol and the limits of quantification was 0.1 microg/L for 3-phenanthrol.The sensitivity, reproducibility and recovery of HPLC-MS/MS method were good for the analysis of 1-naphthol, 2-naphthol, 3-phenanthrol and 1-pyrenol in the urine of people on occupational and nonoccupational exposure to PAHs.

To explore the effects of 2,5-hexandione, the metabolite of n-hexane, on the expression of myelin protein zero (P0) in sciatic nerve and on the positive rate of P0 antibody in serum of rats at different time points.Seventy five Wistar rats were divided into five groups and were administrated with 400 mg/kg 2,5-hexanedione per day for 0, 1, 2, 3 and 4 weeks respectively. The P0 expression at different time points was determined with immunohischemistry and the P0 antibody in serum were detected with enzyme-linked immunosorbent assay.With the administration of 2,5-hexandione, the rats gradually showed the signs of peripheral neuropathy. P0 distribution in transverse section of sciatic nerve was different, and the intensity in myelin sheath was higher than that in axon. The expression of P0 in sciatic nerve of rats with 2,5-hexanedione administration for 0 week seemed higher than those of the other time points, and the expression of the P0 showed a decreasing tendency with the time of 2,5-hexanedione administration. The positive rate of P0 antibody in serum of rats administrated with 400 mg/kg 2,5-hexanedione for 0, 1, 2, 3 and 4 weeks were 33.3%, 26.7%, 46.7%, 46.7% and 84.6% respectively. The positive rate of Po antibodies in serum of rats showed an increasing tendency with the time of 2,5-hexanedione administration (chi2 = 11.007, P0.05).The P0 in sciatic nerve of rats could be destroyed by 2,5-hexanedione and P0 expression level decreased with the time of 2,5-hexanedione administration. The positive rate of P0 antibody in serum increased with the time of 2,5-hexanedione administration in rats.

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.