Study of the Lithium Storage Mechanism of N-Doped Carbon-Modified Cu2 S Electrodes for Lithium-Ion Batteries.

Owing to their high specific capacity and abundant reserve, Cux S compounds are promising electrode materials for lithium-ion batteries (LIBs). Carbon compositing could stabilize the Cux S structure and repress capacity fading during the electrochemical cycling, but the corresponding Li+ storage mechanism and stabilization effect should be further clarified. In this study, nanoscale Cu2 S was synthesized by CuS co-precipitation and thermal reduction with polyelectrolytes. High-temperature synchrotron radiation diffraction was used to monitor the thermal reduction process. During the first cycle, the conversion mechanism upon lithium storage in the Cu2 S/carbon was elucidated by operando synchrotron radiation diffraction and in situ X-ray absorption spectroscopy. The N-doped carbon-composited Cu2 S (Cu2 S/C) exhibits an initial discharge capacity of 425 mAh g-1 at 0.1 A g-1 , with a higher, long-term capacity of 523 mAh g-1 at 0.1 A g-1 after 200 cycles; in contrast, the bare CuS electrode exhibits 123 mAh g-1 after 200 cycles. Multiple-scan cyclic voltammetry proves that extra Li+ storage can mainly be ascribed to the contribution of the capacitive storage.

Response a chronic effects of PBDE-47: Up-regulations of HSP60 and HSP70 expression in freshwater bivalve Anodonta woodiana.

Heat shock proteins (HSPs) play an important role in adaption of environmental stress by protein folding, membrane translocation, degradation of misfolded proteins and other regulatory processes. Our previous study showed oxidative stress generated from polybrominated diphenyl ether-47 (PBDE-47) could cause an acute toxicity on freshwater bivalve Anodonta Woodiana, but the effect of chronic toxicity need to be elucidated. In order to further investigate the chronic effect of PBDE-47, clams A. Woodiana were randomly divided into the PBDE-47 treated group administrated with PBDE-47 at a concentration 3.36 µg/L and control group treated with a similar volume dimethyl sulfoxide. Two complete HSP sequences were isolated from A. Woodianaa and respectively named AwHSP60 and AwHSP70. They were widely distributed in foot, gill, hepatopancreas, adductor muscle, heart, hemocytes and mantle. Administration of PBDE-47 could result in a significant up-regulation of AwHSP60 and AwHSP70 expressions in the hepatopancreas, gill and hemocytes. In the hepatopancreas, compared with that of control group, mRNA level of AwHSP60 increased more than 89.9% (P < 0.05) from day 1-15, AwHSP70 increased more 2.79 times (P < 0.01). In the gill, during experiment observed, expression of AwHSP60 increased more 2.09 times (P < 0.01) in contrasted with that of control group. Significant up-regulation of AwHSP70 expression showed a reversed U shape. In the hemocytes, AwHSP60 and AwHSP70 expressions of PBDE-47 treated group respectively increased more 2.09 times (P < 0.05) and 1.81 times (P < 0.05) compared with that of control group. These results indicated that up-regulations of AwHSP60 and AwHSP70 expression are contribute to enhancing adaption of bivalve A. Woodiana exposed to PBDE-47 treatment.

Molecular cloning, characterization, and the response of Cu/Zn superoxide dismutase and catalase to PBDE-47 and -209 from the freshwater bivalve Anodonta woodiana.

Polybrominated diphenyl ethers-47 (PBDE-47) and -209 are significant components of total PBDEs in water and can catalyze the production of reactive oxygen species (ROS) in the organisms. Anti-oxidant enzymes play an important role in scavenging the high level of ROS. In the current study, two full-length cDNAs of Cu/Zn superoxide dismutase (CuZnSODs) and catalase (CAT) were isolated from freshwater bivalve Anodonta woodiana by rapid amplification of cDNA ends approach and respectively named as AwSOD and AwCAT. The nucleotide sequence of AwSOD cDNA had an open reading frame (ORF) of 465 bp encoding a polypeptide of 155 amino acids in which signature 1 GKHGFHVHEFGDNT and signature 2 GNAGARSACGVI of SODs were observed. Deduced amino acid sequence of AwSOD showed a significant similarity with that of CuZnSODs. AwCAT had an ORF 1536 bp encoding a polypeptide of 512 amino acids which contains a conserved catalytic site motif, and a proximal heme-ligand signature motif of CATs. The time-course expressions of AwSOD and AwCAT in hepatopancreas were measured by quantitative real-time PCR. Expressions of AwSOD and AwCAT showed a significant up-regulation in groups at a low concentration treatment of PBDE-47, a biphasic pattern in groups with a high concentration treatment. Administration of PBDE-209 could result in an up-regulation of AwSOD and AwCAT expressions with time- and dose-dependent matter. These results indicate that up-regulations of AwSOD and AwCAT expression of hepatopancreas of freshwater bivalve A. woodiana contribute to eliminate oxidative stress derived from PBDE-47 and -209 treated.

Long-term exposure to diesel engine exhaust induces primary DNA damage: a population-based study.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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 (p<0.001). Compared with controls, the levels of parameters in normal Comet and FPG-Comet assay were all significantly higher in DEE-exposed workers (p<0.001), 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. CONCLUSIONS: These findings suggest that DEE exposure mainly induces DNA damage, which might be used as an early biomarker for risk assessment of DEE exposure.

Baseline blood levels of manganese, lead, cadmium, copper, and zinc in residents of Beijing suburb.

Baseline blood concentrations of metals are important references for monitoring metal exposure in environmental and occupational settings. The purpose of this study was to determine the blood levels of manganese (Mn), copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd) among the residents (aged 12-60 years old) living in the suburb southwest of Beijing in China and to compare the outcomes with reported values in various developed countries. Blood samples were collected from 648 subjects from March 2009 to February 2010. Metal concentrations in the whole blood were determined by ICP-MS. The geometric means of blood levels of Mn, Cu, Zn, Pb and Cd were 11.4, 802.4, 4665, 42.6, and 0.68 µg/L, respectively. Male subjects had higher blood Pb than the females, while the females had higher blood Mn and Cu than the males. There was no gender difference for blood Cd and Zn. Smokers had higher blood Cu, Zn, and Cd than nonsmokers. There were significant age-related differences in blood levels of all metals studied; subjects in the 17-30 age group had higher blood levels of Mn, Pb, Cu, and Zn, while those in the 46-60 age group had higher Cd than the other age groups. A remarkably lower blood level of Cu and Zn in this population as compared with residents of other developed countries was noticed. Based on the current study, the normal reference ranges for the blood Mn were estimated to be 5.80-25.2 µg/L; for blood Cu, 541-1475 µg/L; for blood Zn, 2349-9492 µg/L; for blood Pb, <100 µg/L; and for blood Cd, <5.30 µg/L in the general population living in Beijing suburbs.

[Polycyclic aromatic hydrocarbons monohydroxy metabolites level in urine of general population in eight provinces of China].

OBJECTIVE: To assess the levels of polycyclic aromatic hydrocarbons monohydroxy metabolites in urine of general population in China among 8 provinces, provide the baseline of the metabolites in the general population. METHODS: From 2009 to 2010, 18 120 subjects of general population aged 6-60 years old were recruited from 24 areas among 8 provinces in east, west and central areas of China mainland by cluster random sampling. The information of the living environment and health condition were collected by questionnaire and spot urine samples were collected, 4 680 urine samples were analysed by high performance liquid chromatography with tandem mass spectrometry, and monohydroxy metabolites distribution in urine among groups of gender and ages were analysed. RESULTS: Geometric means (GM) of 2-naphthol, 1-naphthol, 3-phenanthrol and 1-hydroxypyrene concentration in urine (95%CI) were 1.85 (1.75-1.95), 1.55 (1.50-1.61), 0.57 (0.54-0.59) and 0.82 (0.78-0.85) µg/L, respectively;and median are 2.44, <0.50, 0.72 and 0.90 µg/L, respectively. The concentration between male and female were significantly different (P < 0.01), and the concentration among the groups of population were significantly different (P < 0.01), the GM of 2-naphthol among the groups of population aged 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were 1.60, 1.56, 1.69, 2.23, 1.91 and 1.86 µg/L (χ(2) = 17.90, P < 0.01), the GM of 1-naphthol in the groups were 1.30, 1.16, 1.53, 1.68, 1.80 and 1.52 µg/L (χ(2) = 76.22, P < 0.01), the GM of 3-phenanthrol in the groups were 0.78, 0.76, 0.55, 0.42, 0.50 and 0.99 µg/L (χ(2) = 66.48, P < 0.01), the GM of 1-hydroxypyrene in the groups were 0.77,0.64, 1.00, 0.84, 0.84 and 0.57 µg/L (χ(2) = 51.48, P < 0.01), respectively. CONCLUSION: The distribution of monohydroxy metabolites levels in urine of general population were different, it provided a basic data for the further study of polycyclic aromatic hydrocarbons biomonitoring in the population.

Development of preimplantation genetic testing for monogenic reference materials using next-generation sequencing.

OBJECTIVE: Preimplantation genetic testing for monogenic disorders (PGT-M) has been used for over 20 years to detect many serious genetic conditions. However, there is still a lack of reference materials (RMs) to validate the test performance during the development and quality control of PGT-M. METHOD: Sixteen thalassemia cell lines from four thalassemia families were selected to establish the RMs. Each family consisted of parents with heterozygous mutations for α- and/or ß-thalassemia and two children, at least one of whom carried a homozygous thalassemia mutation (proband). The RM panel consisted of 12 DNA samples (parents and probands in 4 families) and 4 simulated embryos (cell lines constructed from blood samples from the four nonproband children). Four accredited genetics laboratories that offer verification of thalassemia samples were invited to evaluate the performance of the RM panel. Furthermore, the stability of the RMs was determined by testing after freeze‒thaw cycles and long-term storage. RESULTS: PGT-M reference materials containing 12 genome DNA (gDNA) reference materials and 4 simulated embryo reference materials for thalassemia testing were successfully established. Next-generation sequencing was performed on the samples. The genotypes and haplotypes of all 16 PGT-M reference materials were concordant across the four labs, which used various testing workflows. These well-characterized PGT-M reference materials retained their stability even after 3 years of storage. CONCLUSION: The establishment of PGT-M reference materials for thalassemia will help with the standardization and accuracy of PGT-M in clinical use.

Antioxidant and hepatoprotective effect of different extracts of guizhencao (herba bidentis bipinnatae) against liver injury in hyperlipidemia rats.

OBJECTIVE: To investigate the antioxidant and hepatoprotective properties of the different extracts Guizhencao (Herba Bidentis Bipinnatae) against liver injury in hyperlipidemia rats. METHODS: The rats were divided into 7 groups, with 10 rats in each. Rats were treated with high-fat diet for 18 weeks besides the normal control group, then rats in both normal control and model groups were received 5 mL/kg(-1) x day(-1) of saline and those in the positive control group with 2 mg/kg(-1) x day(-1) of lovastatin. Rats in the positive control group and different Guizhencao (Herba Bidentis Bipinnatae) extracts treatment groups (ethyl acetate extract group, n-hexane extract group, ethanol extract group, and aqueous extract group) were treated with corresponding extract at a concentration of 5 mL/kg(-1) x day(-1). After 8 weeks treatment, all rats were sacrificed and total blood samples were collected. Histological analysis of liver was underdone by hematoxylin and eosin. The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), glouse (GLU), cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol were measured according to standard procedure using auto-analyzer. The superoxide dismutase (SOD) and malondialdehyde (MDA) levels in liver were ananlyzed by procedure instruction. RESULTS: The histopathological analysis implied that the administration of Guizhencao (Herba Bidentis Bipinnatae) extracts resulted in hepatoprotective role compared with that of the model group. In addition, the high-fat diet caused a remarkable increase of ALT, AST, GLU, TC, TG, LDL-C and MDA levels. A decline in HDL-C and SOD concentrations and a reversal of effects were observed in different Guizhencao (Herba Bidentis Bipinnatae) extracts groups, especially in the aqueous extract and ethanol extract groups. CONCLUSION: The different extracts of Guizhencao (Herba Bidentis Bipinnatae) can play a protecting role against liver injury in hyperlipidemia rats maybe through decreasing ALT, AST, GLU, TC, TG, LDL-C and MDA levels and enhancing the liver anti-oxidative ability.

Development and characterization of reference materials for EGFR, KRAS, NRAS, BRAF, PIK3CA, ALK, and MET genetic testing.

BACKGROUND: Along with the dramatic development of molecular diagnostic testing for the detection of oncogene variations, reference materials (RMs) have become increasingly important in performance evaluation of genetic testing. OBJECTIVE: In this study, we built a set of RMs for genetic testing based on next-generation sequencing (NGS). METHOD: Solid tumor tissues were selected as the samples of RMs for preparation. NGS was used to determine and validate the variants and the mutation frequency in DNA samples. Digital PCR was used to determine the copy numbers of RNA samples. The performance of the RMs was validated by six laboratories. RESULTS: Thirty common genetic alterations were designed based on these RMs. RMs consisted of a positive reference, a limit of detection reference, and a negative reference. The validation results confirmed the performance of the RMs. CONCLUSION: These RMs may be an attractive tool for the development, validation, and quality monitoring of molecular genetic testing.

An Adaptive Information Security System for 5G-Enabled Smart Grid Based on Artificial Neural Network and Case-Based Learning Algorithms.

With the deployment of 5G Internet of Things (IoT) in the power system, the efficiency of smart grid is improved by increasing two-way interactions in different layers in smart grid. However, it introduces more attack interfaces that the traditional information security system in smart grid cannot response in time. The neuroscience-inspired models have shown their effectiveness in solving security and optimization problems in smart grid. How to improve the security mechanism in smart grid while taking into account the optimization of data transmission efficiency using neuroscience-inspired algorithms is the problem to be solved in this study. Therefore, an information security system based on artificial neural network (ANN) and improved multiple protection model is proposed. Based on the ANN algorithm, the link state sample space is used to train the model to obtain the optimal transmission path in 5G power communication network. Integrating the intelligent link state module, the zero-trust security protection platform using case-based learning algorithm is designed and taken as the first protection, the network security logical isolation facility is taken as the second protection, and the forward and backward isolation facilities are set as the third protection to achieve the strengthened security of 5G IoT in smart grid. The experimental results show the efficiency and effectiveness of the proposed algorithms. In addition, the experimental results also show that the proposed system can resist malicious terminal access, terminal hijacking, data tampering and eavesdropping, protocol fuzzy, and denial-of-service attacks, so as to reduce the security risks of 5G IoT in smart grid. Since the proposed system can be easily integrated into the existing smart grid structure in China, the proposed system can provide a reference for the design and implementation of 5G IoT in smart grid.

[Determination of 19 illegally added chemical ingredients in hair loss prevention cosmetics by ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry].

Cosmetic products for hair loss prevention are often mixed with prohibited substances such as hormones, antibiotics, and forbidden pharmacologically active substances. Although drugs increase the efficacy of cosmetic products, they cause skin irritation and allergic reactions, upon long-term exposure. Given the increasing number of hair loss prevention cosmetics on the market, the need to guarantee product safety calls for efficient and reliable methods to identify illegal ingredients in these products. Chromatography combined with high-resolution mass spectrometry offers the advantages of high resolution and high throughout, thus being a powerful technique for simultaneously detecting illegal ingredients in cosmetics. In this study, an ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS) method for detecting 19 illegal chemical components was established. Combined with the scientific database, a screening platform for hair loss prevention cosmetics was constructed. The effect of extraction solvent was investigated. The chromatographic and mass spectrometry conditions were optimized. Under the optimal conditions, separation was achieved within 20 min on an ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm). Acetonitrile and 2 mmol/L ammonium formate solution containing 0.05% formic acid were used as mobile phases for gradient elution. The 19 compounds were detected by positive ion electrospray ionization (ESI) in the MSE mode. The chromatographic retention time, precursor ions, product ions of the target analytes, and abundance ratio were collected to construct a screening database with UNIFI software. The 19 compounds were well separated, with good linearity. The limits of detection (LODs) and limits of quantification (LOQs) were 0.025-0.05 µg/g and 0.075-0.15 µg/g, respectively. Hair lotion and shampoo, which are commonly marketed as hair loss prevention cosmetics, were selected as the respective matrices for the recovery experiment. The average recoveries of the 19 compounds ranged from 68.6% to 118.6%, and the relative standard deviations (RSDs) were 0.3%-10.3%. Then, 77 batches of cosmetic samples were detected and screened under the same conditions. The TOF-MS information, including the retention time, ion addition mode, mass-to-charge ratio of the parent ions and fragment ions, as well as the abundance ratio, were compared between the cosmetic samples and the standard MS information with UNIFI software. Finally, two batches of samples that were illegally adulterated with minoxidil and finasteride were identified. The ESI fragmentation pathway of the product ions from minoxidil was also proposed. The matrix matching external standard method was used to determine the amounts of minoxidil and finasteride in the two batches of hair lotion, and they were as high as 60 mg/g and 0.31 mg/g, respectively. This result revealed that multiple chemical components were simultaneously added to hair loss prevention cosmetics. Furthermore, the amount of the illegally added drug was very high, indicating high safety risk for consumers using such cosmetics. The present method has the advantages of simple operation, high sensitivity, and good reproducibility. It can be used for rapid screening and simultaneous quantitative analysis of various illegal chemicals in hair loss prevention cosmetics.

The Clinical Features and Management of Empyema Caused by Streptococcus constellatus.

Background: Streptococcus constellatus, a commensal, plays an important role in purulent infections. It has been reported as aggressive pathogen causing pleural empyema. But the role of S. constellatus in empyema has not been taken seriously. There are no studies about clinical characteristics of empyema caused by S. constellatus domestically and abroad. This study aimed to explore the clinical features and management of empyema caused by S. constellatus. Methods: A retrospective review of 9 patients diagnosed with empyema caused by S. constellatus in a hospital between January 2010 and August 2021 was performed. Results: S. constellatus empyema were mostly seen in old males (66.7%) with comorbid diseases. The high-risk factors include diabetes mellitus, oral infection, and oral surgery. All were unilateral encapsulated empyema (right-side, 55.6%), diagnosed with pneumonia (bilateral pneumonia, 88.9%; ipsilateral lung abscess, 44.4%). 33.3% of patients had S. constellatus and anaerobes co-isolated. S. constellatus were sensitive to penicillin G, linezolid, levofloxacin, vancomycin, ceftriaxone, and chloramphenicol, resistant to erythromycin, tetracycline, and clindamycin. 33.3% of the patients needed ventilator support. The primary treatment to S. constellatus empyema was timely pus drainage, intravenous antibiotics, and enough nutrition support, intrapleural fibrinolytics and surgery (VAST recommended first) in necessity. Conclusion: S. constellatus may cause pneumonia and lung abscess first and then spread to cause empyema mainly in old males with comorbid diseases. S. constellatus often co-isolated with anaerobes in empyema. Antibiotics should cover simultaneously both S. constellatus and anaerobes.

[Hypermethylation of O(6)-methylguanine-DNA methyltransferase in human bronchial epithelial cell induced by organic extracts of coke oven emissions].

OBJECTIVE: 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). METHODS: 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. RESULTS: 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, P < 0.05), 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. CONCLUSION: The DNA damage induced by COE might be associated with the suppression of MGMT caused by its hypermethylation.

Research on knowledge dissemination in smart cities environment based on intelligent analysis algorithms: a case study on online platform.

In developing smart cities, the implementation of social connections, collaboration, innovation, exchange of views by observing, exploiting and integrating various types of knowledge is required. The smart cities concept that employs knowledge sharing mechanism can be defined as the concept of a city that utilizes information technology to increase citizens' awareness, intelligence as well as community's participation. The knowledge dissemination via online sharing platforms has been becoming more popular in recent years, especially during the epidemic of infectious diseases. Thus, the social network and emotional analysis method based on intelligent data analysis algorithms is proposed to study the speaker relationship and comment sentiment tendency of a Chinese popular speech (knowledge dissemination) platform: YiXi. In our research, 690 speakers' information and 23,685 comments' information are collected from YiXi website as the data source. The speaker relationship network construction algorithm and emotional analysis algorithm are designed in details respectively. Experiments show that speakers who have the same profession can deliver different types of speeches, indicating that selection of YiXi platform in the invitation of speakers is diversified. In addition, overall sentiment tendency of comments on speeches seem to be slightly positive and most of them are the personal feelings according to their experience after watching speech videos instead of the direct evaluations of speech quality. The research aims to gain an insight into the popular knowledge sharing phenomenon and is expected to provide reference for knowledge dissemination platforms in order to improve the knowledge sharing environment in smart cities.

[Using HPLC-MS/MS method to analyze monohydroxy metabolites of PAHs in urine].

OBJECTIVE: 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). METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Development of a genomic DNA reference material panel for thalassemia genetic testing.

INTRODUCTION: Thalassemia is one of the most common autosomal recessive inherited diseases worldwide, and it is also highly prevalent and variable in southern China. Various types of genetic testing technologies have been developed for diagnosis and screening of thalassemia. Characterized genomic DNA reference materials (RMs) are necessary for assay development, validation, proficiency testing, and quality assurance. However, there are no publicly available RMs for thalassemia genetic testing as yet. METHODS: To address the need for the publicly available DNA RMs for thalassemia genetic testing, the National Institutes for Food and Drug Control and the China National GeneBank established 32 new cell lines with three wild-type genotypes and 29 distinct genotypes of thalassemia which account for approximately 90% thalassemia carriers in China. The genomic DNA of 32 cell lines was characterized by four clinical genetic testing laboratories using different genetic testing methods and technology platforms. RESULTS: The genotyping results are concordant among four laboratories. In addition, the results of stability test demonstrated that the genotypes of these DNA samples are not influenced by preanalytical conditions such as long-term exposure to high-temperature (37°C) environment and repeated freeze-thawing. CONCLUSION: We developed the first national panel of 32 genomic DNA RMs which are renewable and publicly available for the quality assurance of various genetic testing methods and will facilitate research and development in thalassemia genetic testing.

An integrated Asian human SNV and indel benchmark established using multiple sequencing methods.

Sequencing technologies have been rapidly developed recently, leading to the breakthrough of sequencing-based clinical diagnosis, but accurate and complete genome variation benchmark would be required for further assessment of precision medicine applications. Despite the human cell line of NA12878 has been successfully developed to be a variation benchmark, population-specific variation benchmark is still lacking. Here, we established an Asian human variation benchmark by constructing and sequencing a stabilized cell line of a Chinese Han volunteer. By using seven different sequencing strategies, we obtained ~3.88 Tb clean data from different laboratories, hoping to reach the point of high sequencing depth and accurate variation detection. Through the combination of variations identified from different sequencing strategies and different analysis pipelines, we identified 3.35 million SNVs and 348.65 thousand indels, which were well supported by our sequencing data and passed our strict quality control, thus should be high confidence variation benchmark. Besides, we also detected 5,913 high-quality SNVs which had 969 sites were novel and  located in the high homologous regions supported by long-range information in both the co-barcoding single tube Long Fragment Read (stLFR) data and PacBio HiFi CCS data. Furthermore, by using the long reads data (stLFR and HiFi CCS), we were able to phase more than 99% heterozygous SNVs, which helps to improve the benchmark to be haplotype level. Our study provided comprehensive sequencing data as well as the integrated variation benchmark of an Asian derived cell line, which would be valuable for future sequencing-based clinical development.

Suboptimal DNA repair capacity predisposes coke-oven workers to accumulate more chromosomal damages in peripheral lymphocytes.

DNA repair is an essential mechanism for cells to maintain their genomic integrity under endogenous or exogenous assault. Reduced DNA repair capacity (DRC) is associated with increased risk for several environmentally related cancers. The micronucleus in peripheral lymphocytes has been validated as a biomarker of chromosomal damage, increasing cancer risk in human populations. We hypothesized that suboptimal DRC is associated with the increase in chromosomal damage among 94 coke-oven workers and 64 noncoke-oven controls. DRC was evaluated in isolated lymphocytes by comet assay. Chromosomal damage in peripheral lymphocytes was detected by cytokinesis-block micronucleus assay. Four common coding single nucleotide polymorphisms in the XRCC1 gene were genotyped. Coke-oven workers have significantly increased urinary 1-hydroxypyrene (9.0; 6.8-11.7 microg/L versus 1.5, 1.3-1.7 microg/L; P<0.01) and micronucleus frequency (7.4 per thousand+/-4.3 per thousand versus 3.0 per thousand+/-3.0 per thousand; P<0.01), and decreased DRC (55.9%+/-16.4% versus 63.6%+/-18.5%; P<0.01) compared with controls. Significant correlations between DRC and micronucleus frequency were found in coke-oven workers (r=-0.32; P<0.01; n = 94) and all study subjects (r=-0.32; P<0.001; n=158) but not in controls (r=-0.21; P=0.11; n=64). Variants of the Arg399Gln polymorphism were associated with a decreased DRC in both coke-oven workers (51.6%+/-16.1% versus 60.6%+/-15.7%; P<0.01) and controls (59.1%+/-18.5% versus 68.4%+/-17.5%; P=0.04). The complicated interrelationship of these multiple biomarkers was also identified by path analysis. These findings should facilitate developing a biomarker-based risk assessment model for lung cancer in this occupational population.

Biomarkers measured by cytokinesis-block micronucleus cytome assay for evaluating genetic damages induced by polycyclic aromatic hydrocarbons.

Coke oven workers are regularly exposed to polycyclic aromatic hydrocarbons (PAHs) and have a high risk for lung cancer. Limited evidence has demonstrated a direct link between exposure to PAHs and early genetic damage in exposed workers. The cytokinesis-block micronucleus (CBMN) cytome assay is a comprehensive system for measuring DNA damage and cytotoxicity. In the current study, we investigated different chromosomal damage endpoints including micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs), in 141 PAH-exposed subjects and 66 unexposed controls. The frequencies of MN, NPBs and NBUDs were all significantly higher in PAH-exposed workers than in controls (2.4-, 5-, and 3-fold, respectively). We further classified the PAH-exposed workers into different PAHs exposure groups based on their work positions on the oven and their urinary 1-hydroxypyrene and found that the frequencies of NPBs and NBUDs increased with the increasing level of both external and internal PAHs exposure levels. Similar trend was not found for MN due to the reduced MN frequency in the highest PAHs exposure group compared with the second highest PAHs exposure group. Using principal component analysis, we confirmed that the frequencies of NPBs and NBUDs are more sensitive to reflect the external or internal levels of PAHs exposure. In PAH-exposed subjects, NPB and NBUD frequencies were influenced by gender and females have lower frequencies of NPB and NBUD. Taken together, our observations indicate that NPBs and NBUDs are more sensitive and reliable biomarkers for genetic damages induced by PAHs and could potentially be used for the biomonitoring of genotoxin-exposed populations.

Antaxia-telangiectasia mutated gene polymorphisms and susceptibility to chromosomal damage among polycyclic aromatic hydrocarbons exposed workers.

The aim was to explore the relationship between the ataxia-telangiectasia mutated (ATM) gene polymorphisms and susceptibility to cytokinesis-block micronucleus among workers exposed to polycyclic aromatic hydrocarbons (PAH). Blood and urine samples of 140 PAH-exposed workers and 66 non-PAH-exposed workers were collected. Seven tagging single nucleotide polymorphisms in ATM gene were selected by pariwise r(2) method and minor allele frequency cutoff of 0.05 from Chinese genotype data in HapMap project. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to analyze the polymorphisms of ATM rs600931, rs652311, rs227060, rs227292, rs624366, rs189037 and rs228589. The results showed that ATM rs600931 AG and AG+AA genotypes exhibited significantly higher cytokinesis-block micronucleus (CBMN) frequency (11.14+/-6.91 per thousand and 10.57+/-6.82 per thousand) than did the GG genotype (7.66+/-5.69 per thousand, P=0.015 and 0.038, respectively). The subjects with rs189037 GA and GA+AA genotypes exhibited significantly higher CBMN frequency (10.99+/-6.90 per thousand and 10.51+/-6.76 per thousand) than that of the GG genotype (7.72+/-5.82 per thousand, P=0.018 and 0.035, respectively). The PAH-exposed workers with rs624366 GC and GC+CC genotypes exhibited significantly higher CBMN frequency (11.34+/-6.74 per thousand and 10.73+/-6.62 per thousand) than did the GG genotype (7.61+/-6.07 per thousand, P=0.001 and 0.003, respectively). rs227092 GT genotype exhibited significantly higher CBMN frequency (10.78+/-6.60 per thousand) than did the GG genotype (7.91+/-6.30 per thousand, P=0.025) among the PAH-exposed workers. The haplotype pairs GGGGTGC/AAACATT exhibited significantly higher CBMN frequency (12.05+/-7.40 per thousand) than did the GGGGTGC/GGGGTGC (7.51+/-6.19 per thousand, P=0.007) among the PAH-exposed group. In conclusion, it is suggested that the polymorphisms of ATM were associated with the CBMN frequencies among PAH-exposed workers.