[Simultaneous determination of 46 semi-volatile organic compounds in water by liquid-liquid extraction-gas chromatography-mass spectrometry].

Semi-volatile organic compounds (SVOCs) include polycyclic aromatic hydrocarbons (PAHs), phthalic acid esters (PAEs), organochlorine pesticides (OCPs) and nitrobenzenes (NBs). Most of them have carcinogenic, teratogenic, mutagenic and endocrine disrupting effects. Therefore, rapid and accurate determination of SVOCs in water is very important. As the most traditional pretreatment method, liquid-liquid extraction (LLE) has the advantages of wide extraction range, high extraction efficiency, simple operation and lower cost, which is very suitable for the simultaneous extraction of multiclass SVOCs. Dichloromethane has good solubility for most SVOCs, and is slightly soluble in water with low boiling point. It is a good broad-spectrum extractive solvent of organic compounds. But at present, there is no detection standard of SVOCs in water in China. In this study, three factors including nitrogen blowing temperature, pH of water sample and extraction time were optimized. It was aimed to establish a liquid-liquid extraction-gas chromatography-mass spectrometry (GC-MS) method for the simultaneous determination of the 46 SVOCs in water. At first, the effect of nitrogen blowing temperature (30, 35, 40 ℃) was investigated. The results showed that under different nitrogen blowing temperature, the recoveries of the 46 SVOCs were slightly different, but the differences were not significant. Considering the recovery and concentration efficiency, the nitrogen blowing temperature was finally set at 35 ℃. Dichloromethane was selected as the LLE solvent of the SVOCs and its extraction efficiency was investigated. The recoveries of the 46 SVOCs were satisfactory for the determination. Then sample pH (neutral and alkaline condition) was investigated. Most of the SVOCs in this paper have no obvious acid-base property. The extraction effect of water sample under neutral conditions was the best and the most stable, and under alkaline condition, the recovery of each substance was generally low. Finally, extraction time (7, 10, 15 min) was studied. In a certain range, with the increase of extraction time, the recovery also increased, but when the time increased to 15 min, the recovery of some compounds increased or decreased, and the time-consuming was longer, the recovery of most substances could meet the requirements when the extraction time was set to 10 min. The optimized experimental conditions were determined as follows: under neutral conditions, the water sample was extracted by dichloromethane for three times, each extraction time was 10 min, and concentrated at the nitrogen blowing temperature of 35 ℃. GC-MS was used for detection, and internal standard method was used for quantitative analysis. The results showed that the linearity of the method was good in the range of 20-2000 µg/L, the correlation coefficients (r 2) were no less than 0.9916, the limits of detection (LODs, S/N=3) ranged from 0.28 to 16.55 ng/L, and the limits of quantification (LOQs, S/N=10) ranged from 0.92 to 55.16 ng/L. The average recovery was 63.6%-125% at three spiked levels of 0.02, 0.2, 0.4 µg/L, with the relative standard deviations (n=6) ranging from 1.03% to 17.0%. This method was applied for the determination of 27 surface water samples in Jinan section of the Yellow River. The pollutants were mainly PAEs and PAHs, while NBs were not detected, only two kinds of OCPs were detected at some sites. The method is simple, universal, accurate and precise, and has low detection limit. It is suitable for the simultaneous determination of the 46 SVOCs in surface water and groundwater.

Identification of crucial genes associated with rat traumatic spinal cord injury.

The aim of the present study was to investigate the key genes associated with traumatic spinal cord injuries (TSCI). The dataset GSE52763 was downloaded from the Gene Expression Omnibus, for which lumbar spinal cord samples were obtained from rats at 1 and 3 weeks following contusive spinal cord injury and 1 week subsequent to a sham laminectomy, and used to identify differentially expressed genes (DEGs). Functional enrichment analysis, co­expression analysis and transcription factor (TF) identification were performed for DEGs common to the 1 and 3 week injury samples. In total, 234 upregulated and 51 downregulated DEGs were common to the 1 and 3 week injury samples. The upregulated DEGs were significantly enriched in Gene Ontology terms concerning immunity (e.g. Itgal and Ccl2) and certain pathways, including natural killer cell mediated cytotoxicity [e.g. Ras­related C3 botulinum toxin substrate 2 (Rac2) and TYRO protein tyrosine kinase binding protein (Tyrobp)]. The downregulated DEGs were highly enriched in female gonad development [e.g. progesterone receptor (Pgr)], and the steroid biosynthesis pathway. A total of 139 genes had co­expression associations and the majority of them were upregulated genes. The upregulated co­expressed genes were predominantly enriched in biological regulation, including TGFB induced factor homeobox 1 (Tgif1) and Rac2. The downregulated co­expressed genes were enriched in anatomical structure development (e.g. Dnm3). A total of 92 co­expressed genes composed the protein­protein interaction network. Additionally, 9 TFs (e.g. Pgr and Tgif1) were identified from the DEGs. It was hypothesized that the genes including Tgif1, Rac2, Tyrobp, and Pgr may be closely associated with TSCI.

Efficacy evaluation of methotrexate in the treatment of ankylosing spondylitis using meta-analysis.

The aim of this study was to evaluate the efficacy of methotrexate (MTX) in the treatment of ankylosing spondylitis (AS). The literature on controlled clinical trials was searched from MEDLINE, EMBASE, OVID, and Cochrane Library databases up to November 2012. The quality of the studies included was evaluated publicly by two reviewers. A meta-analysis was conducted to the homogeneous studies using Cochrane systematic review. Three trials involving 116 patients compared treatment with MTX against placebo. No statistically significant differences (p < 0.05) were found in the primary outcome measures of withdrawal rate, bath ankylosing spondilitis active index (BASDAI), C-reactive protein (CRP), patient global assessment, and side effects such as nausea and vomiting. Two trials involving 142 patients compared treatment with MTX plus infliximab (IFX) against IFX alone in the effect of treatment of AS. No statistically significant differences (p < 0.05) were found in the primary outcome measures of ASAS20 and withdrawal rate. Thus, we should choose the right drugs based on the specific situation in clinical applications. Randomized controlled trials designed rationally and implemented strictly with multi-center, large sample size and enough follow-up time are needed in future research.

[General and light microscope observation on histological changes of femoral heads between SANFH rabbit animal models and it were intervened by Osteoking].

OBJECTIVE: To evaluate the histological changes on the femoral heads of the SANFH rabbit animal models and after it were intervened by Osteoking (herbs of the Yi minority in Yunnan province) using general and light microscope observation. METHOD: A total of 150 New Zealand white rabbits were randomly divided into a non-treatment control group (A group, n = 24), normal rabbits with Osteoking treatment group (B group, n = 24), and the experimental group (n = 102). The experimental group was injected with escherichia coli endotoxin (10 microg x kg(-1)) into auricular vein twice by 24-hour intervals, and prednisolone (20 mg x kg(-1)) was injected into buttock three times by 24-hour intervals to make steroid-induced femoral head necrosis model. At the fifth week, 48 out of 53 rabbits were equally divided into model group (C group, n = 24, models with non-treatment Osteoking) and abnormal rabbits with Osteoking treatment group (D group, n = 24). B group and D group were intragastrically administrated with Osteoking, once every two days. A group and C group were intragastrically administrated with the equal volume of saline. At 8th, 12th and 16th week after model preparation, the femoral head specimens were observed under the general and a light microscope. RESULT: Macroscopic and light microscopic analysis showed that, clear bone necrosis of femoral head was observed in the C group, and a large number of fat cell proliferation was found in the bone marrow cavity. As compared with C group, the damage level of cells in D group was milder, however, the density of bone trabecula from Osteoking treatment was high, and the ratio of bone lacuna was very low. It is also demonstrated that the surface area of bone necrosis was decreased, and the number of cells from adiposities was reduced significantly. The phenomenon of bone necrosis repaired apparently. The morphology of femoral head from A group and B group is normal. CONCLUSION: It suggested that Osteoking could effectively help repair steroid-induced femoral head necrosis in the early stage.