A risk signature-based on metastasis-associated genes to predict survival of patients with osteosarcoma

Osteosarcoma (OS) is the most common primary solid malignant bone tumor, and its metastasis is a prominent cause of high mortality in patients. In this study, a prognosis risk signature was constructed based on metastasis-associated genes. Four microarrays datasets with clinical information were downloaded from Gene Expression Omnibus, and 256 metastasis-associated genes were identified by limma package. Further, a protein-protein interaction network was constructed, and survival analysis was performed using data from the Therapeutically Applicable Research to Generate Effective Treatments data matrix, identifying 19 genes correlated with prognosis. Six genes were selected by the least absolute shrinkage and selection operator regression for multivariate cox analysis. Finally, a three-gene (MYC, CPE, and LY86) risk signature was constructed, and datasets GSE21257 and GSE16091 were used to validate the prediction efficiency of the signature. The survival times of low- and high-risk groups were significantly different in the training set and validation set. Additionally, gene set enrichment analysis revealed that the genes in the signature may affect the cell cycle, gap junctions, and interleukin-6 production. Therefore, the three-gene survival risk signature could potentially predict the prognosis of patients with OS. Further, proteins encoded by CPE and LY86 may provide novel insights into the prediction of OS prognosis and therapeutic targets.     

Comparative study of the binding mode between cytochrome P450 17A1 and prostate cancer drugs in the absence of haem iron

Abstract

According to the X-ray crystal structures of CYP17A1 (including its complexes with inhibitors), it is shown that a hydrogen bond exists between CYP17A1 and its inhibitors (such as abiraterone and TOK-001). Previous short MD simulations (50?ns) suggested that the binding of abiraterone to CYP17A1 is stronger than that of TOK-001. In this work, by carrying out long atomistic MD simulations (200?ns) of CYP17A1 and its complexes with abiraterone and TOK-001, we observed a binding mode between CYP17A1 and abiraterone, which is different from the binding mode between CYP17A1 and TOK-001. In the case of abiraterone binding, the unfilled volume in the active site cavity increases the freedom of movement of abiraterone within CYP17A1, leading to the collective motions of the helices G and B′ as well as the breaking of hydrogen bond existing between the 3β-OH group of abiraterone and N202 of CYP17A1. However, the unfilled volume in the active site cavity can be occupied by the benzimidazole ring of TOK-001, restraining the motion of TOK-001. By pulling the two inhibitors (abiraterone and TOK-001) out of the binding pocket in CYP17A1, we discovered that abiraterone and TOK-001 were moved from their binding sites to the surface of protein similarly through the channels formed by the helices G and B′. In addition, based on the free energy calculations, one can see that it is energetically favorable for the two inhibitors (abiraterone and TOK-001) to enter into the binding pocket in CYP17A1.     

An improved approach for extraction and high-performance liquid chromatography analysis of paraquat in human plasma

A simple, sensitive, reliable and economical HPLC method for quantifying paraquat concentration in human plasma has been developed, using diethyl paraquat as an internal standard. The drugs were extracted from the sample and separated on Xtimate C18 column with a mobile phase of 15% acetonitrile in 0.1M orthophosphoric acid containing SDS (150 mg/l). The pH of the mobile phase was adjusted to 3 with triethylamine and the detection wavelength was 256 nm for both paraquat and the internal standard. The average extraction recoveries were 91.9%. Good linearity (R(2)=0.9984) was observed throughout the range of 0.02-10 μg/ml in 0.5 ml plasma. The overall accuracy of this method was 97.6-107.3% and the lower limit of detection was 0.01 μg/ml. The intra- and inter-day variations were lower than 3.65% and 2.64%, respectively. We used this method to examine the paraquat concentrations of 53 patients with acute paraquat intoxication of whom 26 (49.1%) survived. In conclusion, this method was suitable for quantification of paraquat plasma concentration in toxicological samples. It was helpful in both assessing the severity of intoxication and predicting the outcome of paraquat poisoning.     

The associations of IL-18 serum levels and promoter polymorphism with tacrolimus pharmacokinetics and hepatic allograft dysfunction in Chinese liver transplantation recipients

Interleukin 18 (IL-18) is a potent proinflammatory cytokine, which promotes the secretions of TNF-α, IL-1β, IL-2 and IFN-γ. All those inflammatory cytokines can influence the CYP450 and MDR dependent drug disposition. On the other side, those cytokines can induce hepatic allograft dysfunction. We investigated the effects of serum IL-18 and IL-18 gene promoter polymorphisms on tacrolimus pharmacokinetics and hepatic allograft dysfunction in liver transplant recipients. A total of 155 liver transplant recipients were enrolled into this study (34 females and 121 males). The mean follow-up was 52 months (range 16-96 months).The total liver transplant recipients were divided into hepatic allograft dysfunction (N = 14) and no hepatic allograft dysfunction (N = 141). We studied two single-nucleotide polymorphisms in the promoter region of IL-18 gene at the position G-137C (rs187238) and A-607C (rs1946518) by HRM analysis (high-resolution melting curve analysis). Tacrolimus dosage, tacrolimus blood concentration, serum levels of IL-18 and IFN-γ were also investigated. We found the recipients with higher IL-18 and IFN-γ serum levels had lower tacrolimus concentration/dose (C/D) ratios (P < 0.05). In the mean time, after transplantation hepatic allograft dysfunction was more likely to happen to those recipients. However, there was no significant difference in the frequencies of A-607C and G-137C allelic distribution in recipients' tacrolimus concentration/dose (C/D) ratios. This study identifies IL-18 reduced tacrolimus concentration/dose (C/D) ratio through up regulation of P-glycoprotein (P-gp).     

抚仙湖窑泥沟人工湿地的除磷效果研究

为了减缓和控制抚仙湖局部湖湾水体富营养化趋势,在抚仙湖北岸建设了净化面积1 hm²的人工湿地.综合利用生物氧化塘、水平潜流人工湿地和表面流人工湿地治理技术,对入湖河道窑泥沟污水中磷的去除效果进行了试验研究.结果表明,该人工湿地系统对磷具有较强的去除能力.总磷去除率在57.7%～81.10%之间,平均去除率为54.9%.单位面积磷滞留量平均为26 mg·m^-2·d^-1,其中,湿地植物同化作用磷滞留量为26.1 mg·m^-2·d^-1,约占磷滞留总量的10%,大部分磷去除是通过基质吸附和沉降作用,但主要湿地植物水芹的季节变化对相应功能区的除磷效果会产生一定影响.试验期间,各功能区单位面积磷滞留量依次为水平潜流人工湿地＞生物氧化塘＞沉淀池＞表面流人工湿地.     

Toxicity evaluation of Meiliang Bay, Lake Taihu, China—a drinking water source

In this study, potential toxicity in organic pollutants in Meiliang Bay, Lake Taihu, a drinking water source, was investigated using the comet assay and zebrafish embryo test, and two control sites in Lake Changdang and the Changjiang (Yangtze) River were established. For the genotoxicity assay, results showed that organic extracts from water samples induce DNA damage on human lymphocytes and mouse testicular cells. A statistically significant difference (p < 0.01) was observed versus the solvent control, as shown by multiple comparisons at a dose of 100 ml tube⁻¹. The degree of DNA damage caused by Meiliang Bay water was most serious (human lymphocytes cells—184 arbitrary units (AU); 234 AU on mouse testicular cells). Organic extracts also affected zebrafish embryo development. Embryo coagulation, axis abnormality, slow absorbability of vitellicle, and multi-edema related to teratogenesis at 96 hpf were observed. In the high dose group, there was obvious edema in the hearts and vitellicles for most dysplastic embryos. Toxic potential in organic pollutants in drinking water sources from the Yangtze River and Lake Changdang were less serious than Meiliang Bay. Therefore, the drinking water source in Meiliang Bay was unsafe compared to the Changjiang River and Lake Changdang, and it is exigent that Meiliang Bay water quality should be ameliorated further.     

Warfarin Dosage Response Related Pharmacogenetics in Chinese Population

Objectives

As the most frequently prescribed anticoagulant, warfarin has large inter-individual variability in dosage. Genetic polymorphisms could largely explain the differences in dosage requirement. rs9923231 (VKORC1), rs7294 (VKORC1), rs1057910 (CYP2C9), rs2108622 (CYP4F2), and rs699664 (GGCX) involved in the warfarin action mechanism and the circulatory vitamin K were selected to investigate their polymorphism characteristics and their effects on the pharmacodynamics and pharmacokinetics of warfarin in Chinese population.

Methods

220 patients with cardiac valve replacement were recruited. International normalized ratio and plasma warfarin concentrations were determined. The five genetic polymorphisms were genotyping by pyro-sequencing. The relationships of maintenance dose, plasma warfarin concentration and INR were assessed among groups categorized by genotypes.

Results

rs9923231 and rs7294 in VKORC1 had the analogous genotype frequencies (D’: 0.969). 158 of 220 recruited individuals had the target INR (1.5–2.5). Patients with AA of rs9923231 and CC of rs7294 required a significantly lower maintenance dose and plasma concentration than those with AG and TC, respectively. The mean weekly maintenance dose was also significantly lower in CYP2C9 rs1057910 mutated heterozygote than in patients with the wild homozygote. Eliminating the influence from environment factors (age, body weight and gender), rs9923231 and rs1057910 could explain about 32.0% of the variability in warfarin maintenance dose; rs7294 could explain 26.7% of the variability in plasma concentration. For patients with allele G of rs9923231 and allele T of rs7294, higher plasma concentration was needed to achieve the similar goal INR.

Conclusions

A better understanding of the genetic variants in individuals can be the foundation of warfarin dosing algorithm and facilitate the reasonable and effective use of warfarin in Chinese.     

转hTNF-α基因在鱼腥藻中表达产物的提取及其初步纯化

研究了转hTNF-α基因鱼腥藻7120(Anabaenasp.PCC 7120)中表达产物的最佳提取条件,并研究目标蛋白hTNF-α对温度耐受度和硫酸铵盐析的条件,对总蛋白和目标蛋白进行了检测。结果表明,hTNF-α的最佳溶出条件为:0.05 mol/L、pH7.5Tris-HCl缓冲液,NaCl的浓度为0.2 mol/L;当温度为55℃时,处理30min,其hTNF-α提取量下降不明显,回收率达到92.08%,可除去约40%的杂蛋白;先用饱和度为30%的硫酸铵沉淀杂蛋白,再用60%的硫酸铵沉淀目标蛋白,又可除去部分杂蛋白。     

The value of plasma paraquat concentration in predicting therapeutic effects of haemoperfusion in patients with acute paraquat poisoning

Objective

This study was aimed to analyze the scavenging effect of haemoperfusion on plasma paraquat (PQ) and to evaluate the clinical significance of PQ examination in the treatment of patients with acute paraquat poisoning.

Methods

85 patients with acute paraquat intoxication by oral ingestion were admitted in West China Hospital from Jun, 2010 to Mar, 2011. A standardized therapeutic regimen including emergency haemoperfusion was given on all subjects. A total of 91 whole blood samples were taken before (0h), underway (1h after haemoperfusion beginning) and at the end (2h) of the haemoperfusion therapy. The clearance rate was calculated and related factors were analyzed.

Results

As heamoperfusion was going on, the plasma paraquat concentration of the patients kept falling down. After 1 hour of haemoperfusion, the average clearance rate (R₁) was 37.06±21.81%. After 2 hours of haemoperfusion, the average clearance rate (R₂) was 45.99±23.13%. The average of R₁/R₂ ratio was 76.61±22.80%. In the high paraquat concentration group (plasma paraquat concentration (C₀) >300 ng/mL), both the averages of R₁ and R₂ were significantly higher than those of the low paraquat concentration group (C₀≤200 ng/mL) (p<0.05), and there was no significant difference of R₁/R₂ between these two groups (p>0.05).

Conclusions

The dynamic monitoring of plasma PQ concentration was not only critical in the clinical evaluation but also helpful in guiding the treatment of patients with acute PQ intoxication. Haemoperfusion can effectively eliminate paraquat from the plasma in patients with high initial plasma PQ concentration, while in patients with low initial plasma PQ concentration (<200 ng/ml), the clearance effect of harmoperfusion was very limited. Increasing HP time might improve the overall clearance rate of HP on plasma PQ yet decrease the elimination efficiency of HP, while repeated HP treatment was helpful against the rebound phenomena.