[Inhibition of GMA-induced ubiquitination process in 16HBE malignantly transformed cells on protein CD44 and MMP14].

OBJECTIVE: To observe the effect of the ubiquitination process on the expression of CD44 antigen(CD44) and matrix metalloproteinase-14(MMP14) in human bronchial epithelial(16HBE) malignantly transformed cells induced by glycidyl methacrylate(GMA). METHODS: Successfully resuscitated 16HBE cells were cultured using a final concentration of 8 µg/mL GMA as the treatment group and 1 µg/mL dimethyl sulfoxide as the solvent control group, each time stained for 72 h, and then stained again after an interval of 24 h. After repeating the staining three times, the cells were cultured in passages respectively. The 40th generation(P40) GMA-treated group and the same-generation solvent control group were subjected to soft agar colony formation assay and concanavalin A(ConA) agglutination test to confirm that the 40th generation of GMA-induced malignant transformed 16HBE cells possessed malignant transformed cell characteristics.5, 10, 20, 40, 60 µmol/L anacardic acid were used to inhibit the ubiquitination process of GMA-induced malignant transformed 16HBE cells. The protein expression of CD44 and MMP14 were detected by western blotting, while the transcript levels of CD44, MMP14, and TFAP2A were assessed by real-time fluorescence quantitative PCR(qPCR). RESULTS: (1) In the soft agar colony formation assay, the number of clones formed by the cells in the solvent control group was 22, and the number of clones created by the malignantly transformed cells in the GMA-treated group was 208. In the ConA agglutination test, the cells in the solvent control group were uniformly dispersed in ConA solution, and no obvious agglutination occurred for 30 min, whereas the cells in the GMA-treated group were agglutinated in the 5th min, and the agglutinated cells were larger and more rapidly agglutinated. The agglomerates were more significant and faster, and the sensitivity of agglutination was increased. (2) After differential inhibition of GMA-induced ubiquitination in malignantly transformed 16HBE cells, the expression levels of CD44 and MMP14 were reduced in GMA-induced malignantly transformed 16HBE cells compared with the control group(P<0.05). The transcript levels of MMP14 and CD44 decreased with increasing inhibitor concentration(P<0.05), and the transcript levels of the upstream transcription factor TFAP2A were also simultaneously reduced(P<0.05). CONCLUSION: Inhibition of the cellular ubiquitination process mediates the down-regulation of protein expression and transcriptional expression of CD44 and MMP14 in GMA-induced malignantly transformed 16HBE cells.

Multi-Omics Analysis Reveals the Pathogenesis of Growth-Disordered Raccoon Dog.

Microorganisms of the genus Eperythrozoon are a zoonotic chronic infectious disease with wide distribution. We found that raccoons infected with Eperythrozoon showed obvious stunting, which seriously affected the economic benefits of raccoon dogs. To investigate the pathogenesis of the raccoon dog, we used transcriptome and proteome sequencing to analyze the changes in mRNA, miRNA, and protein expression in raccoon dogs infected with Eperythrozoon and normal raccoons. The results showed that the expression levels of genes related to immunity, metabolism, and enzyme activity were significantly changed. Among these, ERLIN1, IGF1R, CREB3L1, TNS1, TENC1, and mTOR play key roles. Additionally, the miR-1268, miR-125b, miR-10-5p, and miR-10 as central miRNAs regulate the expression of these genes. Integrated transcriptomic and proteomic analyses revealed consistent trends in mRNA and protein changes in MYH9, FKBP1A, PRKCA, and CYP11B2. These results suggest that Eperythrozoon may contribute to the slow development of raccoons by affecting the expression of mRNAs and miRNAs, reducing their immunity and causing metabolic abnormalities.

Generating Topologically Consistent BIM Models of Utility Tunnels from Point Clouds.

The development and utilization of urban underground space is an important way to solve the "great urban disease". As one of the most important types of urban underground foundations, utility tunnels have become increasingly popular in municipal construction. The investigation of utility tunnels is a general task and three-dimensional laser scanning technology has played a significant role in surveying and data acquisition. However, three-dimensional laser scanning technology suffers from noise and occlusion in narrow congested utility tunnel spaces, and the acquired point clouds are imperfect; hence, errors and redundancies are introduced in the extracted geometric elements. The topology of reconstructed BIM objects cannot be ensured. Therefore, in this study, a hierarchical segmentation method for point clouds and a topology reconstruction method for building information model (BIM) objects in utility tunnels are proposed. The point cloud is segmented into facades, planes, and pipelines hierarchically. An improved mean-shift algorithm is proposed to extract wall line features and a local symmetry-based medial axis extraction algorithm is proposed to extract pipelines from point clouds. A topology reconstruction method that searches for the neighbor information of wall and pipeline centerlines and establishes collinear, perpendicular, and intersecting situations is used to reconstruct a topologically consistent 3D model of a utility tunnel. An experiment on the Guangzhou's Nansha District dataset successfully reconstructed 24 BIM wall objects and 12 pipelines within the utility tunnel, verifying the efficiency of the method.

Safety and tolerability of esketamine in propofol based sedation for endoscopic variceal ligation with or without injection sclerotherapy: Randomized controlled trial.

OBJECTIVES: Esketamine is an S (+) enantiomer of ketamine with greater potency and similar psychomimetic effects compared to racemic ketamine. We aimed to explore the safety of esketamine in different doses as an adjuvant to propofol in patients undergoing endoscopic variceal ligation (EVL) with or without injection sclerotherapy. METHODS: One hundred patients were randomized to receive sedation with propofol 1.5 mg/kg in combination with sufentanil 0.1 µg/kg (group S), esketamine 0.2 mg/kg (group E0.2), esketamine 0.3 mg/kg (group E0.3), or esketamine 0.4 mg/kg (group E0.4) for EVL (n = 25 each). Hemodynamic and respiratory parameters were recorded during the procedure. The primary outcome was the incidence of hypotension; secondary outcomes included the incidence of desaturation, positive and negative syndrome scale (PANSS) after the procedure, pain score after the procedure, and secretion volume. RESULTS: The incidence of hypotension was significantly lower in groups E0.2 (36%), E0.3 (20%), and E0.4 (24%) than in group S (72%). The incidence of SpO2 ≤94% was significantly lower in group E0.4 (4%) than in group S (32%). No significant intergroup difference was found in the PANSS assessment. CONCLUSIONS: Combining 0.4 mg/kg esketamine with propofol sedation was optimal to facilitate EVL with stable hemodynamic status and better respiratory function during the procedure, without significant psychomimetic side-effects. TRIAL REGISTRATION: Chinese Clinical Trial Registry (Trial ID: ChiCTR2100047033, http://www.chictr.org.cn/showproj.aspx?proj=127518).

TMT-based quantitative proteomic analysis reveals the underlying mechanisms of glycidyl methacrylate-induced 16HBE cell malignant transformation.

Glycidyl methacrylate (GMA) has been widely used as tackifying/crosslinking copolymer monomer in the industrial section. Occupational and environmental exposure to GMA is inevitable. GMA is classified as a Group 2 A carcinogen. However, it still lacks a sufficient understanding of its carcinogenicity at the protein level. The major pathways and players during the malignant transformation process remain unknown. In this study, we first established and characterized a malignant transformation model using human bronchial epithelial (16HBE) cells exposed to 8 µg/mL GMA. Then the proteomics approach, western-blot analysis as well as quantitative PCR (qPCR) analysis were employed to investigate its underlying mechanisms of carcinogenicity. Our results showed that the 16HBE cells exposed to GMA and passaged to the 40th generation had undergone a malignant transformation. Proteomic analysis revealed that 123 proteins were significantly up-regulated while 160 proteins were down-regulated during the process of malignant transformation. Importantly, further pathway analysis identified the extracellular matrix-receptor (ECM-receptor) interaction pathway to be one of the major players mediating the process and most of the differentially expressed proteins (DEPs) were up-regulated, including two vital proteins, CD44 and MMP14, as well as members from integrin family. These results provide direct proteomic evidence that DEPs related to the ECM-receptor interaction pathway play an active role in reinforcing the carcinogenicity of GMA. The findings of this study might deepen our understanding of the underlying mechanisms of GMA carcinogenicity and thus facilitate the risk assessment of GMA.

[Role of LncRNA CASC11 in the malignant transformation of 16HBE cells induced by glycidyl methacrylate].

OBJECTIVE: To investigate the effect of trending up-regulation LncRNA CASC11 which is differentially expressed during the malignant transformation of human bronchial epithelial cells(16 HBE) induced by glycidyl methacrylate(GMA). METHODS: After 16 HBE cells were repeatedly exposed to low concentration GMA(8 µg/mL), the 10 th, 20 th and 30 th passage cells of the GMA group and the DMSO solvent control group were collected. High throughput LncRNA microarray were used to screen the differentially expressed LncRNAs at different stages. Short Time-series Expression Miner and bioinformatics tool RPISeq were used to screen and predict the potential targets of specific LncRNA. Real-time fluorescent quantitative PCR(qPCR) and Western blot were used to detect the relative expression of specific LncRNA and the content of its target protein respectively. RESULTS: The specific differential expression of LncRNA CASC11 in the process of GMA-induced malignant transformation of 16 HBE cells showed a trend of up-regulation. Compared with the control cells in the same period, the P10, P20 and P30 generation cells were down-regulated by 1.64 times, up-regulated by 2.01 times, and up-regulated by 2.66 times, respectively. Western blot showed that the levels of cyclin-dependent kinase 1(CDK1), cyclinB1 and cyclinB2 in P10, P20 and P30 cells after exposure were lower than those in DMSO control group during the same period, which was consistent with the microarray results. CONCLUSION: The differential expression of LncRNA CASC11 in the process of GMA-induced 16 HBE cell malignant transformation was up-regulated trendingly. It is speculated that it may block or delay cell cycle progression by inhibiting CDK1.

[Role of LINC00310 in the glycidyl methacrylate-induced malignant transformation of human bronchial epithelial cell].

OBJECTIVE: To investigate the expression and biological significance of LINC00310 in the malignant transformation of human bronchial epithelial cells(16 HBE) induced by glycidyl methacrylate(GMA). METHODS: The 16 HBE cells recovered successfully used 1 µg/mL dimethyl sulfoxide(DMSO) as the solvent control group, and the final concentration was 8 µg/mL GMA as the treatment group, and were subcultured after repeated exposure 3 times for 72 hours each time. The 10 th, 20 th and 30 th generation cells of the GMA treatment group and corresponding DMSO control group were collected. The LncRNA microarrays was used to analyze the expression changes of LINC00310 in different periods, and the target gene and function prediction was performed by NCBI and cBioPortal bioinformatics database, and real-time quantification PCR(qPCR) was used to detect the relative expression levels of LINC00310 and predicted target genes. RESULTS: The result of the microarray showed that LINC00310 in the GMA-treated group was down-regulated by 2. 02-fold, up-regulated by 6. 17-fold, and up-regulated by 2. 03-fold in the pre-transformation, mid-term, and late, respectively. The result of qPCR confirmed that the expression of LINC00310 relative expression level of 10 th, 20 th and 30 th generation cells was consistent with the microarray result, which were down-regulated by 2. 76-fold, up-regulated by 2. 68-fold, and up-regulated by 3. 09-fold. Consistently, the relative expression of the target gene C-Myc was statistically significant in 20 th and 30 th generation cells. CONCLUSION: LINC00310 induced low expression in the early stage of malignant transformation of 16 HBE cells induced by GMA, and was highly expressed in the middle and late stages. It indicated that LINC00310 may play a cancer-promoting role in the process of cell malignant transformation through C-Myc.

Phylodynamic analysis of two amino acid substitutions in the hemagglutinin protein of canine distemper virus strains detected in fur-bearing animals in China.

Canine distemper virus (CDV) causes a highly contagious disease in a wide range of carnivores. The hemagglutinin (H) protein of viruses shows the highest variability and plays an important role in modulation of viral antigenicity, virulence, and receptor recognition. Since 2012, canine distemper (CD) outbreaks in fur-bearing animals (minks, foxes, raccoon dogs) caused by CDV variants with I542N and Y549H substitutions in the H protein have been frequently reported in China. To characterize the molecular evolutionary dynamics and epidemiological dynamics of CDV, 235 H gene sequences of CDV wild-type strains collected from 22 countries between 1975 and 2015, including 44 strains predominant in fur-bearing animals in China, were analyzed. The phylogenetic relationships and evolutionary rates of the CDV strains were determined by Bayesian phylogenetics. The CDV strains clustered into distinct geographic genotypes, irrespective of the species of isolation. All the variant strains formed a distinct monophyletic cluster and belonged to the F sub-genotype within the Asia-1 genotype-currently the predominant sub-genotype in fur-bearing animals in China. Evolutionary analysis suggested that the variant strains originated in 2006. Furthermore, the selection pressure analysis revealed that the Y549H substitution was under positive selection pressure for adaptation toward the fur-bearing animals. The residue at position 549 also showed structural interaction with the V domain of the mink signaling lymphocyte-activation molecule (SLAM) receptor based on the homology modeling of the H-SLAM complex. Our results suggested that the Y549H substitution contributed to the molecular adaptation of CDV variants in the fur-bearing animals during the viral evolutionary phase in China.

PE17 protein from Mycobacterium tuberculosis enhances Mycobacterium smegmatis survival in macrophages and pathogenicity in mice.

The capacity of Mycobacterium tuberculosis to survive and cause disease is strongly correlated with its ability to escape multiple defense strategies in hosts. In particular, M. tuberculosis has the remarkable capacity to survive within the hostile environment of macrophages. Here, we found that the PE17 (Rv1646) protein promoted intracellular survival of M. smegmatis in peritoneal macrophages from mice. Further experiments confirmed that the recombinant PE17 protein was localized in the cell wall of M. smegmatis. Results from the macrophage infection model showed that PE17 significantly downregulated pro-inflammatory cytokines (interleukin-6, interleukin-12, and tumer necrosis factor-α) secretion from macrophages induced by M. smegmatis and promoted macrophage necrosis. Furthermore, a C57BL/6 mouse infection model confirmed that PE17 significantly prolonged the survival of M. smegmatis in vivo and aggravated lesions in organs of infected mice. Moreover, persistent high levels of interferon-γ and interleukin-1ß in infected mice indicated that the bacteria were not easily removed in vivo. Overall, our present results suggested that the PE17 may act as an important pathogenic factor in M. tuberculosis.

Dracorhodin Perochlorate attenuates Staphylococcus aureus USA300 virulence by decreasing α-toxin expression.

α-Toxin, a pore-forming toxin secreted by most Staphylococcus aureus, plays critical role in the pathogenesis associated with various infectious diseases. The USA300 which is a major international epidemic methicilin-resisrant S. aureus has spread rapidly to multiple countries and become an emerging public health concern. In this study, the in vitro efficacy of Dracorhodin Perochlorate (DP) against USA300 virulence was evaluated. Using susceptibility testing, immunoblots, rabbit blood haemolytic assay and real-time RT-PCR, we observed that the α-toxin production was decreased when USA300 was co-cultured with different sub-inhibitory concentration of DP. Further, the protective effect of DP against USA300-mediated injury of human alveolar epithelial cells (A549) and MH-S cells was evaluated by cytotoxicity assays, and the result revealed that DP, at final concentration of 16 µg/ml, is a potent antagonist for USA300-mediated cell damage. Importantly, those beneficial effects might partially correlate with hla and RNAIII suppression by DP, leading to the inhibition of α-toxin production in culture supernatant. Overall, these results suggest that DP could attenuate the virulence of USA300 by decreasing α-toxin production without inhibiting bacterial growth, and this compound may represent an ideal candidate for the development of anti-virulence agent combating S. aureus infection.

Prevalence, risk factors and molecular characterization of Enterocytozoon bieneusi in raccoon dogs (Nyctereutes procyonoides) in five provinces of Northern China.

The disease microsporidiosis is found worldwide and is mainly caused by Enterocytozoon bieneusi. E. bieneusi can infect a wide range of hosts; however, information regarding the prevalence and genotyping of E. bieneusi infection in raccoon dogs (Nyctereutes procyonoides) is limited. Therefore, in 2015, we examined 305 faecel samples from 80 farmed raccoon dogs in Jilin Province, from 54 in Hebei Province, from 72 in Liaoning Province, from 29 in Shandong Province, and from 40 in Heilongjiang Province. The overall prevalence of E. bieneusi infection in farmed raccoon dogs was 22.30%. Logistic regression analysis suggests that age, gender and region of raccoon dogs were highly related to the prevalence of E. bieneusi infection. Moreover, six E. bieneusi internal transcribed spacer (ITS) region sequences, including four known genotypes, namely D, CHN-DC1, NCF2, and CHN-F1, and two novel genotypes (NCR1 and NCR2), were identified in the present study. The present study firstly indicated the existence of E. bieneusi genotypes NCF2, NCR1, NCR2and CHN-F1 in infected raccoon dogs in Northern China. Integrated control strategies should be implemented to limit E. bieneusi infection in farmed raccoon dogs, and to prevent transmission of this disease to other animals and humans.

Evaluation of MIRU-VNTR for typing of Mycobacterium bovis isolated from Sika deer in Northeast China.

BACKGROUND: Bovine tuberculosis has led to serious economic losses for Sika Deer producers in China. Strategies for controlling the spread of Mycobacterium bovis are often hampered by a lack of epidemiological data. Specifically, tracing infections requires the ability to trace back infections, which, in turn, requires the ability to determine isolates with a common source. This study was planned to assess the discriminatory power of each mycobacterial interspersed repetitive unit (MIRU)-variable number tandem repeats (VNTR) locus and evaluate the most appropriate combination of MIRU-VNTR loci for molecular epidemiological studies on Sika Deer in China. RESULTS: The discriminatory power of MIRU-VNTR typing based on 22 known loci (12 MIRUs, 2 ETRs, 4 QUBs, and 4 Mtubs) were assessed in 96 Mycobacterium bovis strains collected sequentially from Sika Deer at a slaughterhouse in northeastern China. We defined four loci (MIRU4, ETRA, QUB11b, and Mtub4) as highly discriminative, eight loci (MIRU2, MIRU23, MIRU27, MIRU31, MIRU39, MIRU40, QUB26, and Mtub21) as moderately discriminative, and three loci (MIRU16, Mtub30, and Mtub34) as poorly discriminative. The final locus showed no polymorphism between strains. MIRU-VNTR typing as a whole was highly discriminative, with an overall allelic diversity of 0.897. Of the loci tested, the four highly discriminative loci and eight moderately discriminative loci proved to be most appropriate for first line typing of M. bovis from Sika Deer, with the same resolving ability as all 22 loci (H = 0.897). CONCLUSIONS: MIRU-VNTR typing is quick and effective for typing bovine tuberculosis isolates from Sika Deer in China.

[Anti-oncogene of opioid binding protein/cell adhesion molecule-like methylation status in malignant transformation of human bronchial epithelial cells induced by glycidyl methacrylate].

OBJECTIVE: To analyze the opioid binding protein/cell adhesion molecule-like (OPCML) methylation status at different stages of malignant transformation of human bronchial epithelial (16HBE) cells induced by Glycidyl Methacrylate (GMA) and to explore the effect of OPCML methylation in the process of malignant transformation. METHODS: Cells were harvested at different stages (the 10th generation, the 20th generation and the 30th generation). To verify the Methylation chip result of OPCML methylation status in the process of malignant transformation, we detected it by methylation-specific-PCR (MSP); Real-time fluorescence Quantitative PCR (qPCR) were applied to measure the gene expression levels of OPCML at different transformed stage, and compared with the control groups (treated with DMSO). RESULTS: Based on the result of methylation chip, the gene of OPCML methylation occurred in all stages, which was consistent to the result of MSP; qPCR showed that the levels of gene expression decreased in the 20th generation and 30th generation. CONCLUSION: Methylation status of OPCML gene promoter could be considered as a stable and specific biomarker in the transformation process.

[Determination of 2, 4-dichlorophenoxyacetic acid in air of workplace by high-performance liquid chromatography].

OBJECTIVE: To develop a method for determination of 2, 4-dichlorophenoxyacetic acid (2, 4-D) in the air of workplace by high-performance liquid chromatography. METHODS: 2, 4-D was collected by ultrafine glass filters, desorbed by methanol, separated by a C18 column, and detected by a UV detector. Identification and quantification of 2, 4-D were performed by retention time and peak areas, respectively. RESULTS: The linear range of the test was 2∼200 µg/ml; the elution efficiency was 94.6%- 95.9%; the limit of detection (S/N = 3) was 0.034 µg/ml (injection volume of 20 µl eluant); the lower limit of quantification (S/N = 10) was 0.11 µg/ml; the minimum detectable concentration was 0.011 mg/m(3); the minimum quantifiable concentration was 0.037 mg/m(3) (with sampled air volume of 45 L). CONCLUSION: This method is convenient and simple in sample collection and preparation, and satisfies all methodological requirements. Therefore, this method is useful for the determination of 2, 4-D in the air of workplace.

[Method for determining brodifacoum in workplace air by high-performance liquid chromatography].

OBJECTIVE: To establish a method for determining brodifacoum in workplace air by high-performance liquid chromatography (HPLC). METHODS: Brodifacoum in workplace air was collected with a polytetrafluoroethylene filter and desorbed by mixed solution of methanol and dichloromethane (20:80, V:V), and was then separated using an ODS column and determined by an ultraviolet detector; retention time was used for identification, and peak area was used for quantification. RESULTS: The concentration of brodifacoum showed a linear relationship with peak area within 0.2∼10.0 µg/ml; the elution efficiency was 91.6%∼95.1%; the detection limit was 0.08 µg/ml (injection volume: 20 µl eluate); the minimum detectable concentration was 0.000 67 mg/m(3) (calculated by 240 L air sample). CONCLUSION: This HPLC method is convenient and simple for air collection and sample preparation and meets the methodological requirements. Therefore, this method can be used for the determination of brodifacoum in workplace air.

Novel antimicrobial metabolites produced by Sika deer-associated Actinomyces sp. JN411010.

Three novel metabolites (1, 5 and 10) were isolated from a 25-L fermentation broth of Actinomyces sp. JN411010 together with 11 related compounds. Their structures were determined on the basis of 1D and 2D NMR, as well as HR-ESI-MS spectroscopic data analyses. Compounds 1-2, 5-8 and 10 displayed moderate antimicrobial activities against Gram-positive and Gram-negative bacteria. Biosynthetic pathway of 5 and 10 was proposed to be catalysed by polyketide and non-ribosomal peptide gene clusters, respectively.

[Effects of CdTe QDs on chromosome aberration of CHL cells in vitro].

OBJECTIVE: To observed the chromosome oberration of CHL cells induced by CdTe QDs. METHODS: The chromosome oberration test of Chinese hamster lung (CHL) cell was conducted in CdTe QDs at the concentrations of 1.6, 3.2, 6.3, 12.6 and 25.2 microl/ml, under the metabolic (+S9) and non-metabolic (-S9) activation systems. RESULTS: The chromosome oberration rate of 12.6 and 25.2 microl/ml CdTe QDs groups were significantly higher than the control groups (P<0.01) Under the condition of metabolic activation. Main types of chromosomal aberrations was broken, fragmented and exchange. CONCLUSION: It was suggested that CdTe QDs could induce the effects of chromosome oberration under the metabolic activation systems (+S9).

[Methylation status of P16 gene during malignant transformation of human bronchial epithelial cells induced by glycidyl methacrylate].

OBJECTIVE: To analyze the methylation status of P16 gene at the different stages of malignant transformation of human bronchial epithelial cells (16HBE) induced by glycidyl methacrylate (GMA) and to explore the DNA methylation mechanisms. METHODS: The cells exposed to GMA were harvested at the end of exposure (early stage), the 10th generation (protophase) and the 30th generation (anaphase), respectively. The methylation status of P16 promotor was detected by Methylation-specific PCR (MSP). The transformed 16HBE cells were compared with the normal 16HBE cells and the cells exposed to DMSO for methylation status. RESULTS: At the early stage and protophase stage, the non-methylation status in P16 gene promotor of the normal 16HBE cells and the cells exposed to DMSO appeared, the methylation status in P16 gene promotor of the 16HBE cells exposed to GMA was detected to some extension. At the anaphase stage, the methylation status in P16 gene promotor of the 16HBE cells exposed to GMA or DMSO was detected to some extension. CONCLUSION: Methylation status of P16 gene promoter was specific at the early stage and protophase stage of malignant transforming in 16HBE cells induced by GMA, which can serve as an early sensitive biological indicator for malignant transforming in 16HBE cells induced by GMA.

[Determination of brodifacoum in rat plasma by HPLC].

OBJECTIVE: A determination method of brodifacoum in rat plasma with bromadiolone as an internal standard was developed. METHODS: A volume of 10 microl internal standard (bromadiolone) was added into rat plasma, and then extracted by 0.5 ml of acetonitrile by shaking for 2 min. The residue was dissolved with 200 microl of mobile phase after centrifugation for 10 min, and evaporation to dryness by Nitrogen blowing. A C18 column and PDA detector were used for separating and detecting. The wavelength was 254 nm, the flow rate was 1.0 ml/min, and the injection volume was 20 microl. RESULTS: The liner range was 1.0-20 microg/ml, and the correlation coefficient was 0.9992. The detection limit was 0.3 microg/ml in plasma (S/N=3). The intra-assay and inter-assay coefficients of variation were 1.89%-2.45% and 2.51%-3.61% respectively. The recoveries in plasma at levels of low, middle and high concentrations were (80.8 +/- 3.1)%, (81.8 +/- 2.7)% and (87.9 +/- 3.6)% (n=6), respectively. The accuracies were 84.1%-91.5% and 86.7%-93.2%, respectively. CONCLUSION: This method is simple, fast and accurate for the determination of brodifacoum in rat plasma.

[Chromosome damage of human bronchial epithelial cells induced by glycidyl methacrylate].

OBJECTIVE: To observed the chromosome damage of human bronchial epithelial cells induced by glycidyl methacrylate (GMA). METHODS: Chromosome aberration analysis of human bronchial epithelial cells treated with GMA at different dosages (4, 8, 12, 16 and 20 microg/ml), times (1, 2 and 3 times), and phases (10th, 30th genetation) was detected. RESULTS: In the dosages range from 4 to 20 microg/ml, the aberration rates (3%, 6%, 7%, 11% and 14%) were demonstrated increasingly with the increase of exposure doses, and dose-effect relationship was found. Significant differences were observed when treated with GMA three times (6%, 7% and 10%). Structure aberrations were found in the transformed 10th-generation cells, while number aberrations were mainly manifested in the transformed 30th-generation cells. CONCLUSION: The chromosome aberration can be induced by GMA in the human bronchial epithelial cells, from the structure aberration at the beginning to the lack of normal nuclear style.