Microcystin-LR (MC-LR) is a very common toxic cyanotoxins threating ecosystems and the public health. This study aims to explore the long-term effects and potential toxicity mechanisms of MC-LR exposure at environmental levels on colorectal injury. We performed histopathological, biochemical indicator and multi-omics analyses in mice with low-dose MC-LR exposure for 12 months. Long-term environmental levels of MC-LR exposure caused epithelial barrier disruption, inflammatory cell infiltration and an increase of collagen fibers in mouse colorectum. Integrated proteotranscriptomics revealed differential expression of genes/proteins, including CSF1R, which were mainly involved in oxidative stress-induced premature senescence and inflammatory response. MC-LR induced chronic inflammation and fibrosis through oxidative stress and CSF1R/Rap1b signaling pathway were confirmed in cell models. We found for the first time that long-term environmental levels of MC-LR exposure caused colorectal chronic inflammation, fibrosis and barrier disruption via a novel CSF1R/Rap1b signaling pathway. Moreover, MC-LR changed the gut microbiota and microbial-related metabolites in a vicious cycle aggravating colorectal injury. These findings provide novel insights into the effects and toxic mechanisms of MC-LR and suggest strategies for the prevention and treatment of MC-caused intestinal diseases.
Non-small cell lung cancer (NSCLC) is a major type of lung cancer with high morbidity and mortality. Long noncoding RNAs (lncRNAs) have been reported to be important in development and progression of NSCLC. However, the role of lncRNA SFTA1P remains unclear. This study aims to explore the clinical roles, biological function, and mechanism of SFTA1P in NSCLC. SFTA1P expression was estimated by the quantitative real-time polymerase chain reaction (qRT-PCR) of 90 pairs of tissue samples, the Cancer Genome Atlas (TCGA) database and microarray. After overexpressing SFTA1P, NSCLC cell proliferation, cycle, and apoptosis were detected. We found that the expression of SFTA1P was significantly downregulated in NSCLC tissues with high diagnostic value (AUC = 0.87), which was consistent with the results of TCGA and microarray data. For the analysis of clinical features, the results revealed that SFTA1P expression was closely related to the pathological type (P < 0.01). Furthermore, the cell function results suggested that the overexpression of SFTA1P triggered cell cycle arrest in the S-phase (P < 0.05). From a mechanistic perspective, the results showed that the PI3K-AKT signaling pathway was inhibited after overexpression of SFTA1P in NSCLC. Taken together, this work supported that SFTA1P may play a suppressing role in the tumorigenesis of NSCLC by modulating PI3K-AKT signaling pathway to influence cell cycle, which provides a potential and prospective biomarker for NSCLC.
D-Glyceric acid (D-GA) is a glycerol derivative with various promising biological functions. This paper reports the adsorption of D-GA from aqueous solution using a strong basic resin. The effect of pH on the uptake of D-GA was studied, and several models were used to investigate the interactions of D-GA and the resin. A theoretical model based on ion exchange and adsorption was developed to fit the isotherms under various pH or temperatures. Kinetic experiments under different initial D-GA concentrations were also performed to define the controlling mechanism of the overall adsorption process. The results showed that the uptake process of D-GA was controlled by the rate of D-GA diffusion through the polymeric matrix of the resin. This study provides valuable information and theoretical support for the scale-up and optimization of operating conditions for the recovery of D-GA.
D-Glyceric acid (D-GA) is a promising chemical for minimizing the toxic effect of acetaldehyde.It has been successfully produced by bioprocesses using glycerol as a substrate.However, high concentrations of glycerol are not beneficial for cell growth.A two-step culture strategy was employed to deal with the ambivalent culture conditions between the growth of Acetobacter tropicalis and the biosynthesis of D-GA.The first stage focuses on biomass accumulation with low initial glycerol concentration; the second stage provides D-GA accumulation through whole-cell biocatalysis.Approximately 2-fold of D-GA yield and 4.5-fold of D-GA productivity were gained by the two-step culture strategy compared to the traditional fermentation with 150 g L -1 of glycerol.Our results also showed that A. tropicalis was able to catalyze the conversion of glycerol to D-GA in the presence of up to 10 % methanol.These findings have important implications to enhance D-GA yield by strategy optimization and reduce its cost.
A method for the simultaneous determination of spirotetramat and its four metabolites in citrus was developed by ultra-high performance liquid chromatography-triple quadrupole-ion trap mass spectrometry (UPLC-Q TRAP MS).The samples were extracted with acetonitrile and purified by QuEChERS pretreatment.The extracts were detected using an electrospray ionization (ESI) positive ion source under multiple reaction monitoring (MRM) mode, and quantified by matrix matching external standard method.The results showed that spirotetramat and its four metabolites had good linearities in the range of 2-1000 μg/L with correlation coefficients (R2) greater than 0.99.The limits of detection (LODs) of spirotetramat and its four metabolites were in the range of 0.08 to 0.49 μg/kg, while the limits of quantification (LOQ) were in the range of 0.26 to 1.62 μg/kg.The average spiked recoveries were in the range of 94.0% to 98.70%, and the relative standard deviations were 1.1%-5.3%.The results from field trials showed that the contents of the final residues of spirotetramat and its four metabolites in the flesh, peel and whole fruit samples were 5.93-14.20, 11.30-17.86 and 1.30-16.51 μg/kg with the highest recommended dose of 60 mg/kg (active ingredient).The residues in harvested citrus were lower than the national standard maximum residue limit (1.00 mg/kg).The method is simple, rapid and accurate, with a high sensitivity and good separation effect, and the effect of matrix interference can be effectively reduced.The accuracy and precision of this method can meet the requirements of quantitative analysis.The method is suitable for the qualitative and quantitative detection of spirotetramat and its four metabolites in citrus.
Through separating and identifying the noise sources of diesel engine, each independent noise obtained can be used as reference for the noise reduction, condition monitoring and fault diagnosis. In the noise source identification of diesel engine, the combustion noise and the piston slap noise are found to be overlapped in time domain and frequency domain. So it is intricate to accurately separate them. Therefore, the noise source identification method which is based on variational mode decomposition (VMD), robust independent component analysis (RobustICA) and continuous wavelet transform (CWT) is proposed. In the test, a 6-cylinder diesel engine was tested in a semi-anechoic chamber. The lead wrapped method was adopted to wrap No. 1–5 cylinders so as to isolate the interference noises, only the No. 6 cylinder part was bared. The single channel noise signal of cylinder head was measured. Then the variational mode decomposition algorithm is utilized to decompose the noise signal into several variational mode components. The RobustICA algorithm is adopted to extract the independent components. Finally, the continuous wavelet transform and the prior knowledge of diesel engine are applied to further identify the separated results. The results show that by using the proposed method to separate and identify the radiation noise of the cylinder head of the diesel engine, the independent components obtained are respectively the combustion noise and the piston slap noise. Comparing with the EEMD-RobustICA-CWT method, each independent noises obtained through the proposed method are more accurate and pure with less other interference noises.
Salmonella enterica has been concerned globally due to its serious contamination in the food industry and serious risks to human health. In this study, the diversity of growth, genotypic virulence and clustered regularly interspaced short palindromic repeats (CRISPR) locus of 17 Salmonella enterica isolates from meat-related sources was evaluated. The results showed that the tested isolates exhibited significant differences (p < 0.05) in the growth kinetic behaviors, the growth rate was independent on serotype, and the fast-growing pattern was observed in Sinstorf serotype. The fold-change of nine genes involved in six virulence units showed isolate-to-isolate variation (p < 0.05), virulence genes associated with SPI-2 and SPI-4 displayed high expression. Relative lower expression levels of tested genes were obviously found in serotypes of Sinstorf, Stanley and Aberdeen. A considerable high diversity in repeats length and space numbers of both CRISPR-1 and CRISPR-2 among tested isolates was also observed, even within serotypes, which was also confirmed by the phylogenetic relationships. No significant relationship between the expression levels of each tested gene and the numbers of CRISPR spaces was observed. The information indicated that the variability among isolates of Salmonella with respect to their behavioral aspects is extensive, and assessment of strain variability is quite indispensable.
The present study was aimed to investigate the mechanistic aspect of endosulfan toxicity and its protection by taurine in rat testes. Pre-treatment with taurine (100 mg/kg/day) significantly reversed the decrease in testes weight, and the reduction in sperm count, motility, viability and daily sperm production in endosulfan (5 mg/kg/day)-treated rats. Sperm chromatin integrity and epididymal L-carnitine were markedly decreased by endosulfan treatment. Endosulfan significantly decreased the level of serum testosterone and testicular 3β-HSD, 17β-HSD, G6PDH and LDH-X. Sperm Δψm and mitochondrial cytochrome c content were significantly decreased after endosulfan. Testicular caspases-3, -8 and -9 activities were significantly increased but taurine showed significant protection from endosulfan-induced apoptosis. Oxidative stress was induced by endosulfan treatment as evidenced by increased H2O2 level and LPO and decreased the antioxidant enzymes SOD, CAT and GPx activities and GSH content. These alterations were effectively prevented by taurine pre-treatment.In conclusion, endosulfan decreases rat testes weight, and inhibits spermatogenesis and steroidogenesis. It induces oxidative stress and apoptosis by possible mechanisms of both mitochondria and non-mitochondria pathways. These data provide insight into the mode of action of endosulfan-induced toxicity and the beneficial role provided by taurine to counteract endosulfan-induced oxidative stress and apoptosis in rat testis.
Penile squamous cell carcinoma (PSCC) is a rare tumor associated with high-risk human papillomavirus (HR-HPV) infection in 30% to 60% of cases. Altered expression of miRNAs has been reported in HPV-related cervical and head and neck cancers, but such data have not been available for PSCC. We analyzed a series of 59 PSCCs and 8 condylomata for presence of HPV infection, for p16INK4a, Ki-67, and p53 immunohistochemical expression, and for expression of a panel of cellular miRNAs (let-7c, miR-23b, miR-34a, miR-145, miR-146a, miR-196a, and miR-218) involved in HPV-related cancer. HR-HPV DNA (HPV16 in most cases) was detected in 17/59 (29%) PSCCs; all penile condylomata (8/8) were positive for low-risk HPV6 or HPV11. HR-HPV+ PSCCs overexpressed p16INK4a in 88% cases and p53 in 35% of cases, whereas HR-HPV− PSCCs were positive for p16INK4a and p53 immunostaining in 9% and 44% of cases, respectively. Among the miRNAs investigated, expression of miR-218 was lower in PSCCs with HR-HPV infection and in p53− cancers. Hypermethylation of the promoter of the SLIT2 gene, which contains miR-218-1 in its intronic region, was frequently observed in PSCCs, mainly in those with low miR-218 expression. Epigenetic silencing of miR-218 is a common feature in HR-HPV+ PSCCs and in HR-HPV− PSCCs without immunohistochemical detection of p53.
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental and occupational pollutants. To date, the effect and mechanism by which PAHs exposure impaired hematopoietic system remains unclear.We examined the capability of PAHs to disrupt hematopoiesis in a study of 639 male participants in China by measuring complete blood counts (CBC) in 2013 and 2014. Gas chromatography–mass spectrometry (GC/MS) method was used to measure airborne levels of PAHs and benzene. We measured 1-hydroxypyrene (1-OHP), S-phenylmercapturic acid (SPMA) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in urinary by ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS/MS) method.We found decreased dose−response of white blood cells, eosinophils, monocytes and lymphocytes with increased PAHs exposure in two consecutive years. We did not find association between benzene with CBC in our study. After stratification analysis by smoking status, the findings were highly consistent. White blood cells, monocytes and red blood cell counts were decreased in high urinary 8-OHdG group.Our study showed that PAHs could impair the hematopoietic system independently, and oxidative stress might play an important role in potential hematotoxicity.
In this report, galactosylated poly(ethylene glycol) methacrylate-st-3-guanidinopropyl metha-crylamide copolymers (galactosylated PEGMA-st-GPMA, GGP) are developed as siRNA carriers to inhibit Survivin mRNA expression. GGPs are combined with Survivin siRNAs to form siRNA/GGP polyplexes. The polyplexes particles were examined by a dynamic light scattering. It showed that GGP copolymers could condense siRNA to form particles with diameter from 128 to 423 nm and zeta potential value in the range from +2.4 to +14.9mV at various charge ratios (N/P). The MTT assay data of siRNA/GGP polyplexes on human hepatocellular liver carcinoma cells (HepG2) and human cervix epithelial carcinoma cells (HeLa) indicated that GGP copolymer had better cell viabilities than polyethyleimine (PEI). The transfection of siRNA/GGP polyplexes was detected by real-time quantitative PCR (RT-qPCR) in HepG2 cell line. We found that the siRNA/GGP polyplexes could effectively silence Survivin mRNA expression in the serum-free media (p<0.01). In the presence of 10% serum medium, the Survivin mRNA expressed has significant difference between siRNA/GGP polyplexes and blank (p<0.05). The galactose competition assay showed that galactosylated PEGMA-st-GPMA (GGP) may provide the targeting to HepG2 cells mediating by asialoglycoproteins receptors (ASGP-R). Furthermore, Survivin siRNA/GGP polyplexes could significantly (p<0.01) inhibit both HepG2 tumor growth and Survivin protein expression in vivo studies in a xenograft mouse model.
Background In the present study, a well-defined glucose and guanidine based copolymer, galactosylated 2-hydroxypropyl methacrylamide-s-3-guanidinopropyl methacrylamide (HPMA-s-GPMA) abbreviated as GGH was prepared and self-assembled with small hairpin RNA (shRNA) to inhibit human telomerase reverse transcriptase (hTERT) gene expression in vitro to develop a shRNA carrier.Methods First, HPMA-s-APMA copolymers were synthesized by aqueous reversible addition-fragmentation chain transfer polymerization, followed by galactosylation and guanidinylation. Then, three target shRNAs containing green fluorescent protein gene as a reporter were combined with GGH to form shRNA/GGH polyplexes.Results GGH copolymers could condense shRNA to form shRNA/GGH polyplex particles with a diameter in the range 122.8-331.6 nm in phosphate-buffered saline, and zeta potential values ranging from +3.7 to +16.5 mV at various charge ratios (N/P). That the cytotoxicity of GGH copolymers was significantly lower than that of PEI in human hepatocellular liver carcinoma cells (HepG2) and human cervix epithelial carcinoma cells. The transfection efficiency of shRNA/GGH polyplexes was higher than that of PEI at a charge ratio of 12 in the HepG2 cell line. Furthermore, shRNA/GGH polyplexes could effectively silence hTERT mRNA expression in serum-free medium (p<0.01) and decrease the aggregation of protein in the medium with the presence of 10% serum. In addition, hTERT mRNA expression in HepG2 cells demosntrate a significant difference between siRNA/GGH polyplexes and blank samples (p<0.05).Conclusions GGH copolymers could integrate advantages relating to galactose content for hepatocyte targeting, guanidino groups for cell penetration and HPMA component for shielding, showing great potential for effective hepatocyte targeting gene delivery. Copyright (C) 2014 John Wiley & Sons, Ltd.
Abstract In this report, a series of well-defined glucose- and guanidine-based cationic copolymers as gene carriers were developed to inhibit human telomerase reverse transcriptase (hTERT) gene expression. First of all, guandinylated 3-gluconamidopropyl methacrylamide-s-3-aminopropyl methacrylamide copolymers (guanidinylated GAPMA-s-APMA, abbreviated as GGA) were prepared via aqueous reversible addition – fragmentation chain transfer polymerization (RAFT). Then, three target hTERT siRNA TERT-1, TERT-2 and TERT-3 were designed and combined with GGA copolymers to form siRNA/GGA polyplexes. The polyplexes were examined by dynamic light scattering and agarose gel electrophoresis. The results indicated that GGA copolymers can condense siRNA effectively to form particles with the diameter from 157 nm to 411 nm and zeta potential values in the range from +3.7 to +15.8 mV at various charge ratios (N/P). The MTT assay data of siRNA/GGA polyplexes on human hepatocellular liver carcinoma cells (HepG2) indicated that GGA copolymer had better cell viabilities than polyethylenimine (PEI). Furthermore, the transfection of siRNA/GGA polyplexes was detected by real-time quantitative PCR (RT-qPCR) in HepG2. It was found that siRNA/GGA polyplexes could effectively silence hTERT mRNA expression in serum-free media (p < 0.01). In the presence of serum, the hTERT mRNA expression in HepG2 cells have significant difference (p < 0.01) between siRNA/GGA3 polyplexes and blank. The results showed that the GAPMA component can reduce the aggregation of protein in serum media. Therefore, the enhancement of transfection may be attributed to the combination of guadino groups and glucose component. And, the guandinylated 3-gluconamidopropyl methacrylamide-s-3-aminopropyl methacrylamide copolymers might be promise in gene delivery.
GalactosylatedN-3-guanidinopropylmethacrylamide-co-poly (ethylene glycol) methacrylate copolymers (galactosylated GPMA-co-PEGMA, GGP) were developed in order to promote transfection efficiency in the presence of serum in this report. First of all, the galactosylated PEGMA-co-GPMA copolymers were prepared via aqueous reversible addition fragmentation chain transfer polymerization (RAFT) of poly (ethylene glycol) methacrylate (PEGMA) with long circulating chain segment and N-3-aminopropyl methacrylamide (APMA) followed by galactosylation and guanidinylation. After that, GGP/plasmid DNA complexes were examined by a dynamic light scattering and gel electrophoresis. It is showed that GGP copolymers have effective condensing ability. The cytotoxicity of GGP was measured by MTT assay. It was found that all the GGP/plasmid DNA complexes had less cytotoxic effects on HepG2 cells than HeLa cells, and the galactose groups reduced the cytotoxicity of complexes with high charge ratios to HepG2 cells. Finally, the transfection efficiency of the galactosylated PEGMA-co-GPMA copolymers was investigated by luciferase expression assay. The results revealed that the copolymers with galactose groups more than 5.83% could induce the asialoglycoprotein (ASGP) receptor mediated transfection, which improved the transfection efficiency in target cells. The GPMA-co-PEGMA copolymers with 54.57% hydrophilic chain segment PEG should prevent the aggregation of protein on the GGP/pDNA complexes, and GGP with 7.94% galactose graft exhibited the highest transfection in the presence of serum. (C) 2013 Elsevier Ltd. All rights reserved.
Abstract Background LncRNAs, range from 200 nt to >100 kilobases (kb), demonstrate a wide range of structural and functional roles through the regulation of a metastable epigenome and transcriptional network. Recently, accumulating evidence indicates aberrant expression of LncRNAs may play an important role in cancer biology. Objective To study the profile of differentially expressed LncRNAs in esophageal cancer tissues and the adjacent normal tissues, and to find out the possible function of LncRNAs involved in the process of tumor development preliminarily. Methods The total RNA were extracted from esophageal cancer tissues and the adjacent normal tissues and were quantified by the NanoDrop ND-1000 and standard denaturing agarose gel electrophoresis. Each sample was amplified and transcribed into fluorescent cRNA along the entire length of the transcripts without 3’ bias utilizing a random priming method. The labeled cRNAs were hybridized onto the Human LncRNA Array v2.0 (8 x 60K, Arraystar) including the global profiling of 33,045 human LncRNAs and 30,215 coding transcripts and then were scanned by the Agilent Scanner G2505B. Quantile normalization and subsequent data processing were performed using the GeneSpring GX v11.5.1 software package (Agilent Technologies). Differentially expressed LncRNAs and mRNAs with statistical significance were identified through Volcano Plot filtering or Fold Change filtering. Pathway analysis and GO analysis were applied to determine the roles of those differentially expressed mRNAs played in biological pathways or GO terms. Finally, Hierarchical Clustering was performed to show the distinguishable LncRNAs and mRNAs expression pattern among samples. Results With a criterion of Fold Change >= 2.0 and P-value <= 0.05, 1019 of differentially expressed LncRNAs were identified in esophageal cancer tissues, including 399 of overexpressed LncRNAs and 620 of downexpressed LncRNAs. The top 10 of aberrant LncRNAs were AK022914, chr10:127700955-127703336, LOC284233, RP11-38M15.6, RNU12, FAM25E, C21orf81, AK095500, AC009336.24, and RP11-397A15.4. Using GENCODE annotation of human genes, 11 of differentially expressed enhancer-like LncRNAs and their nearby coding genes were identified. In addition, there were 25 of differentially expressed lincRNAs and nearby coding gene pairs associated with esophageal cancer according to John Rinn reported lincRNAs profiling. The differentially expressed transcripts were further identified and the matched coding genes adjacent to differentially expressed LncRNAs (distance < 300kb) showed participating in the processes of cell cycle, cell differentiation, protease activities, and et al according to GO analysis and Pathway analysis. Conclusions The results suggests a specific profile of differentially expressed LncRNAs in esophageal cancer, which function prediction implies the broad participation in the processes of oncogenesis. Citation Format: Ran Liu, Miao Yang, Juan Liao, Yi Wang, Enchun Pan, Wei Guo, Lihong Yin, Yuepu Pu. A pilot study of long non-coding RNA expression profile in esophageal cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1835. doi:10.1158/1538-7445.AM2013-1835 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.