19 research outputs found
Soil mobility of surface applied polyaromatic hydrocarbons in response to simulated rainfall
Polyaromatic hydrocarbons (PAHs) are emitted from a variety of sources and can accumulate on and within surface soil layers. To investigate the level of potential risk posed by surface contaminated soils, vertical soil column experiments were conducted to assess the mobility, when leached with simulated rainwater, of six selected PAHs (naphthalene, phenanthrene, fluoranthene, pyrene, benzo(e)pyrene and benzo(ghi)perylene) with contrasting hydrophobic characteristics and molecular weights/sizes. The only PAH found in the leachate within the experimental period of 26 days was naphthalene. The lack of migration of the other applied PAHs were consistent with their low mobilities within the soil columns which generally parallelled their log Koc values. Thus only 2.3% of fluoranthene, 1.8% of pyrene, 0.2% of benzo(e)pyrene and 0.4% of benzo(ghi)perylene were translocated below the surface layer. The PAH distributions in the soil columns followed decreasing power relationships with 90% reductions in the starting levels being shown to occur within a maximum average depth of 0.94 cm compared to an average starting depth of 0.5 cm. A simple predictive model identifies the extensive time periods, in excess of 10 years, required to mobilise 50% of the benzo(e)pyrene and benzo(ghi)perylene from the surface soil layer. Although this reduces to between 2 and 7 years for fluoranthene and pyrene, it is concluded that the possibility of surface applied PAHs reaching and contaminating a groundwater aquifer is unlikely
Matrix Metalloproteinase-9 Expression and Status of Cervical Lymph Nodes in Patients with Nasopharyngeal Carcinoma
Tumor growth and metastasis in nasopharyngeal carcinoma (NPC) patients was suspected as a role of several molecular biomarkers that have been identified in tumor specimens of patients with NPC. Invasion and metastasis process was a complex mechanism which involved some proteolytic enzymes, such as matrix metalloproteinase-9 (MMP-9). To analyze the association of MMP-9 expression of NPC patients with cervical lymph node metastasis. The study was conducted in oncology unit of ORL-HNS at Dr. Soetomo General Hospital Surabaya from May to July 2015. Formalin-fixed paraffin-embedded biopsy specimens from NPC patients with WHO type II and III of histopathology and clinically were divided into four state of cervical enlargement (N0. N1. N2 and N3). The expression of MMP-9 was obtained with immunohistochemistry using rabbit polyclonal antibody Anti-MMP9 ab7299 from abcam®. Cambridge-UK. Thirty-two NPC patients were enrolled in this study. The study found a negative expression of MMP-9 in 3.12% of samples. Spearman rho test result was p = 0.001 with correlation coefficient of 0.754. Spearman test resulted p value of 0.001 with a correlation coefficient of 0.754. Correlation of matrix metalloproteinase-9 expression with cervical lymph node metastasis (N0, N1, N2, and N3) in patients with NPC showed a significant result (p < 0.05). There was a strong positive correlation between MMP-9 expressions with cervical lymph node status in NPC patients
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