Theoretical analysis of naproxen reaction with sulfate and hydroxyl radicals in the aqueous phase: Investigating reactive sites and reaction kinetics.

In this study, we have utilized theoretical calculations to predict the reaction active sites of naproxen when reacting with radicals and to further study the thermodynamics and kinetics of the reactions with ·OH and SO. The evidence, derived from the average local ionization energy and electrostatic potential, points to the naphthalene ring as the preferred site of attack, especially for the C2, C6, C9, and C10 sites. The changes in Gibbs free energy and enthalpy of the reactions initiated by ·OH and SO ranged between -19.

Whole-transcriptome sequencing with ceRNA regulation network construction and verification in glioblastoma.

Objectives: To explore the key genes involved in the occurrence and development of glioblastoma (GBM) by analyzing whole-transcriptome sequencing and biologic data from GBM and normal cerebral cortex tissues and to search for important noncoding RNA (ncRNA) molecular markers based on the competitive endogenous RNA (ceRNA) network.

Methods: Ten GBM and normal cerebral cortex tissues were collected for full transcriptome sequencing, screened for differentially expressed (DE) mRNAs, miRNAs, lncRNAs, and circRNAs, and subjected to bioinformatic analysis. We constructed a Protein-Protein Interaction (PPI) network and a circRNA/lncRNA-miRNA-mRNA regulatory network and identified them using reverse transcription-quantitative polymerase chain reaction (RT-qPCR).

Reaction of antibiotic sulfadiazine with manganese dioxide in aqueous phase: Kinetics, pathways and toxicity assessment.

Sulfonamide antibiotics are often detected in terrestrial and aquatic environment, but little is known about abiotic degradation of these antibiotics. In the present study, the degradation of the sulfonamide antibiotic sulfadiazine by a synthesized δ-MnO was investigated. The initial reaction rate of sulfadiazine oxidized by manganese dioxide increased as the solution pH decreased by weakening electrostatic attraction between sulfadiazine and MnO and enhancing the reduction potential of MnO.

Phthalates in plastic bottled non-alcoholic beverages from China and estimated dietary exposure in adults.

Concentrations of six phthalates were determined in 69 plastic bottled non-alcoholic beverages collected from marketplaces in China. Di-n-butyl phthalate (DBP) and di-(2-ethylhexyl)-phthalate (DEHP) were the most detected compounds with frequencies of 100%. Dimethyl phthalate was found less, with a mean frequency of almost 34%.

Chemical oxidation of sulfadiazine by the Fenton process: kinetics, pathways, toxicity evaluation.

This paper investigated sulfadiazine oxidation by the Fenton process under various reaction conditions. The reaction conditions tested in the experiments included the initial pH value of reaction solutions, and the dosages of ferrous ions and hydrogen peroxide. Under the reaction conditions with pH 3, 0.

[Study on the chemical components of volatile oil from Euphorbia pekinensis radix].

Objective: To analyze the volatile oil from Radix Euphorbia Pekinensis.

Methods: Volatile oil was extracted from Radix Euphorbia Pekinensis by steam distillation and GC-MS was employed for detecting the content of the constituents. The relative content of the chemical constituents were calculated using area normalization method.

Biological degradation and microbial function effect of norfloxacin in a soil under different conditions.

This paper investigated the degradation kinetics of norfloxacin in a soil, and its effects on soil respiration and nitrogen transformation under different conditions. Compared to the sterile control, the degradation rates of norfloxacin in the non-sterile soil were greatly enhanced, suggesting that microorganisms played a major role in the degradation. Accelerated degradation for norfloxacin in the soil was observed with decreasing concentrations (30 mg/kg to 5 mg/kg) with its half-life decreasing from 62 days to 31 days.

[Association of IL-8 gene polymorphisms with inflammatory bowel disease in Chinese patients].

Objective: To investigate the association of interleukin 8 (IL-8) gene polymorphisms with the risks of inflammatory bowel disease (IBD).

Methods: Single nucleotide polymorphisms (SNPs) of IL-8 gene at -845 T/C, -738 T/A, -353 A/T, -251 T/A and +678 T/C were analyzed in 183 IBD patients. They included Crohn's disease (CD, n = 41), ulcerative colitis (UC, n = 142) and healthy controls (n = 160).

Transcriptome analysis of adaptive heat shock response of Streptococcus thermophilus.

Streptococcus thermophilus, a gram-positive facultative anaerobe, is one of the most important lactic acid bacteria widely used in the dairy fermentation industry. In this study, we have analyzed the global transcriptional profiling of S. thermophilus upon temperature change.

Notch signaling dependent differentiation of cholangiocyte-like cells from rhesus monkey embryonic stem cells.

Rhesus monkey embryonic stem (rES) cells have similar characteristics to human ES cells, and might be useful as a substitute model for preclinical research. Notch signaling is involved in the formation of bile ducts, which are composed of cholangiocytes. However, little is known about the role of Notch signaling in cholangiocytic commitment of ES cells.

[Association of combined polymorphisms in MIP-1α and ApoE genes with the susceptibility of inflammatory bowel disease].

Objective: To investigate whether the macrophage inflammatory protein 1 alpha (MIP-1α) and apolipoprotein E (ApoE) gene polymorphisms, either alone or in combination, affect the susceptibility to inflammatory bowel disease (IBD).

Methods: Genomic DNA of IBD patients with Crohn's disease (CD, n = 41) and with ulcerative colitis (UC, n = 142) and healthy controls (n = 160) was extracted and genotyped for the MIP-1α and ApoE gene polymorphisms by restriction fragment length polymorphism assay.

Results: MIP-1α -906(TA)(6)/(TA)(6) homozygotes had a significantly elevated risk of UC (OR = 1.

Trends in the occurrence of human and veterinary antibiotics in the sediments of the Yellow River, Hai River and Liao River in northern China.

The occurrence of four classes of 17 commonly used antibiotics (including fluoroquinolones, tetracycline, sulfonamides, and macrolides) was investigated in the sediments of the Yellow River, Hai River and Liao River in northern China by using rapid resolution liquid chromatography-tandem mass spectrometry. Higher concentrations were detected for most antibiotics in the sediments of the Hai River than in the sediments of the other rivers. Norfloxacin, ofloxacin, ciprofloxacin and oxytetracycline in the three rivers were most frequently detected with concentrations up to 5770, 1290, 653 and 652 ng/g, respectively.

Spatial and seasonal distribution of selected antibiotics in surface waters of the Pearl Rivers, China.

The distribution and occurrence of 15 antibiotics in surface water of the Pearl River System (Liuxi River, Shijing River and Zhujiang River) and effluents of four wastewater treatment plants (WWTPs) were investigated in two sampling events representing wet season and dry season by using rapid resolution liquid chromatography-electrospray tandem mass spectrometry (RRLC-MS/MS) in positive ionization mode. Only eight antibiotics (sulfadiazine, sulfapyridine, sulfamethazine, sulfamethoxazole, trimethoprim, roxithromycin, erythromycin-H₂O and norfloxacin) were detected in the water samples of the three rivers and the effluents. The detection frequencies and levels of antibiotics in the dry season were higher than those in the wet season.

Occurrence and a screening-level risk assessment of human pharmaceuticals in the Pearl River system, South China.

Ten nonsteroidal antiinflammatory drugs (NSAIDs), two blood lipid regulators (BLRs), and two antiepileptic drugs (AEDs) were analyzed in the Pearl River system in China (i.e., Liuxi, Zhujiang, and Shijing Rivers) and four sewage effluents during the dry and wet seasons, and the environmental risks they posed were assessed.

Rapid resolution liquid chromatography-tandem mass spectrometry method for the determination of endocrine disrupting chemicals (EDCs), pharmaceuticals and personal care products (PPCPs) in wastewater irrigated soils.

A multiresidue analytical method was developed for the determination of 9 endocrine disrupting chemicals (EDCs) and 19 pharmaceuticals and personal care products (PPCPs) including acidic and neutral pharmaceuticals in water and soil samples using rapid resolution liquid chromatography-tandem mass spectrometry (RRLC-MS/MS). Solid phase extraction (SPE), and ultrasonic extraction combined with silica gel purification were applied as pretreatment methods for water and soil samples, respectively. The extracts of the EDCs and PPCPs in water and soil samples were then analyzed by RRLC-MS/MS in electrospray ionization (ESI) mode in three independent runs.

Simultaneous determination of four classes of antibiotics in sediments of the Pearl Rivers using RRLC-MS/MS.

A simultaneous extraction and analysis method was developed for four classes of antibiotics: sulfonamides (SAs), macrolides (MLs), fluoroquinolones (FQs) and tetracyclines (TCs) in sediment. The antibiotics in the sediment were extracted by using an optimized mixed solution (citric buffer: acetonitrile, 50:50 v/v), and analyzed by rapid resolution liquid chromatography-tandem mass spectrometry (RRLC-MS/MS) equipped with electrospray ionization source in the positive mode. The recoveries for the antibiotics in the spiked sediment were: 66.

Occurrence and risks of triclosan and triclocarban in the Pearl River system, South China: from source to the receiving environment.

We investigated two commonly used antimicrobial agents triclosan (TCS) and triclocarban (TCC) in the Pearl River system in China (i.e., Liuxi, Zhujiang and Shijing Rivers) and four sewage effluents during dry and wet seasons.

Dissipation of oxytetracycline in soils under different redox conditions.

This study investigated the dissipation kinetics of oxytetracycline in soils under aerobic and anoxic conditions. Laboratory experiments showed that the dissipation of oxytetracycline in soil followed first-order reaction kinetics and its dissipation rates decreased with increasing concentration. Oxytetracycline dissipated faster in soil under aerobic conditions than under anoxic conditions.

Degradation behavior of sulfadiazine in soils under different conditions.

This study investigated the degradation of sulfadiazine in three soils and also determined its sorption and hydrolysis behaviors as well. At the spike concentration of 10 mg/kg, the half-lives for sulfadiazine in the aerobic nonsterile soils ranged from 12 days to 18 days. Sulfadiazine was more persistent in the anoxic soils with the half-lives ranging between 57 days and 237 days and soil microorganisms played little role in the dissipation process under anoxic conditions.

Effects of six selected antibiotics on plant growth and soil microbial and enzymatic activities.

The potential impact of six antibiotics (chlortetracycline, tetracycline and tylosin; sulfamethoxazole, sulfamethazine and trimethoprim) on plant growth and soil quality was studied by using seed germination test on filter paper and plant growth test in soil, soil respiration and phosphatase activity tests. The phytotoxic effects varied between the antibiotics and between plant species (sweet oat, rice and cucumber). Rice was most sensitive to sulfamethoxazole with the EC10 value of 0.

Determination of phenolic endocrine disrupting chemicals and acidic pharmaceuticals in surface water of the Pearl Rivers in South China by gas chromatography-negative chemical ionization-mass spectrometry.

An analytical method for phenolic endocrine disrupting chemicals and acidic pharmaceuticals in river water was developed using gas chromatography mass spectrometry (GC-MS) coupled with negative chemical ionization (NCI) technique, and used for the determination of these compounds in the Pearl Rivers (Liuxi, Zhujiang and Shijing Rivers). Derivatization using pentafluorobenzoyl chloride (PFBOCl) and pentafluorobenzyl bromide (PFBBr) before GC-MS analysis were applied and optimized for phenolic compounds and acidic compounds, respectively. The target compounds were analyzed for river waters from the upstream to downstream of the Pearl Rivers.

Fungal degradation of metsulfuron-methyl in pure cultures and soil.

A fungal strain capable of utilizing metsulfuron-methyl as sole carbon and energy sources was isolated from a metsulfuron-methyl treated soil. The degradation characteristics of metsulfuron-methyl by this fungal strain were investigated in liquid culture and soil. More than 79% of metsulfuron-methyl at concentrations of 0.