Effects of Chelating Surfactants on Competitive Adsorption of Lead and Zinc on Loess Soil

The study of competitive adsorption of heavy metals on soil is important for heavy metals contaminated soil remediation. However, there have been few studies on the impact of desorption reagents on heavy metal adsorption in soil. Batch adsorption studies were used to investigate the competitive adsorption mechanism of two heavy metals, Pb and Zn, on a loess soil in the presence of a new chelating surfactant, sodium N-lauroyl ethylenediamine triacetate (LED3A). Results showed that competitive adsorption equilibria of Pb and Zn were reached at 3 and 10 h, respectively. The maximum equilibrium adsorption capacities were 19.55 and 18.35 g.kg-1, respectively. LED3A affected the competitive adsorption kinetics of Pb and Zn by increasing the change in external mass transfer and reducing the change in internal mass transfer. LED3A reduced Pb and Zn adsorption capacities onto the soil through competitive chelation of the heavy metals. The heavy metal chelating ability of LED3A was higher for Zn than for Pb. When its concentration was larger than 5 g.L-1, LED3A showed a significant effect on the competitive adsorption of Pb and Zn. In the competitive system, the effect of Pb concentration on the Zn adsorption capacity was greater than the effect of Zn concentration on the Pb adsorption capacity. LED3A weakened the effect of Pb concentration and enhanced the effect of Zn concentration. LED3A showed a significant potential for efficiently leaching remediation of Pb and Zn co-contaminated soil.

Long noncoding RNA SNHG8 promotes the proliferation of osteosarcoma cells by downregulating miR-542-3p

Small nucleolar RNA host genes (SNHGs) as a subset of long noncoding RNAs (lncRNAs) have critical roles in the pathogenesis of multiple malignancies, however, the role and molecular mechanisms of lncRNA SNHG8 in osteosarcoma (OS) remain unclear. In the present study, the correlation of SNHG8 or miR-542-3p with clinicopathological elements and prognosis in OS patents was estimated by TCGA cohort. Cell viability and invasion were assessed by MTT and Transwell assays. The interplay between SNHG8 and miR-542-3p was affirmed by a luciferase report assay. The effects of SNHG8 on miR-542-3p expression were examined in MG-63 and SW-1353 cells by qRT-PCR analysis. The results showed that incremental expression of SNHG8 or reduced expression of miR-542-3p was related to poor survival and tumor recurrence in OS patients. Overexpressing SNHG8 accelerated the growth and invasion of MG-63 cells, but silencing SNHG8 harbored an opposite effect in SW-1353 cells. Additionally, SNHG8 could negatively regulate miR-542-3p expression and bind with miR-542-3p, which attenuated SNHG8 induced cell proliferation. Taken together, these findings indicate that lncRNA SNHG8 promotes the proliferation of OS cells by downregulating miR-542-3p.

[Levels of dichlorodiphenyltrichloroethane internal exposure levels in pregnant women of Xiamen and influencing factors]

Objective: To investigate the level of and factors influencing internal exposure to dichlorodiphenyltrichloroethane (DDT) in pregnant women. Methods: In all, 1 064 pregnant women were recruited in a hospital of Xiamen. Participants were asked to complete a questionnaire to obtain data on sociodemographic characteristics and lifestyle. Peripheral venous blood and cord blood samples were collected. Of the 1 064 pregnant women, 600 were enrolled in this study after completing the questionnaire and providing peripheral venous blood and cord blood. Among those women, 150 were selected randomly using a systematic sampling method. A gas chromatography coupled electron capture detector was used to determine the concentration of six DDT homologues: p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), o,p'-dichlorodiphenyltrichloroethane (o,p'-DDT), p,p'-dichlorodiphenyldichloroethane (p,p'-DDD), o,p'-dichlorodiphenyldichloroethane (o,p'-DDD), p,p'-dichlorodiphenylethylene (p,p'-DDE), and o,p'-dichlorodiphenylethylene (o,p'-DDE) . Pregnant women were divided into two groups according to DDT concentration: a low concentration group (detection value≤P₅₀) and a high concentration group (detection value>P₅₀). multivariate logistic regression was used to analyze the association between the DDT levels and potential influencing factors which investigated in the questionnaire. Results: The detection rates of p,p'-DDT, o,p'-DDT, p,p'-DDD, o,p'-DDD, p,p'-DDE and o,p'-DDE in the peripheral venous blood samples from the 150 pregnant women were 83.3% (125), 29.3% (44), 58.0% (87), 24.0% (36), 82.0% (123), and 34.7% (52), respectively. The median concentrations were 1.56, 0.03, 0.07, 0.03, 0.93 and 0.03 μg/ml, respectively. The detection rates of p,p'-DDT, o,p'-DDT, p,p'-DDD, o,p'-DDD, p,p'-DDE and o,p'-DDE in the cord blood samples were 69.3% (104), 10.7% (16), 29.3% (44), 20.7% (31), 81.3% (122) and 45.3% (68), and the median concentrations were 0.41, 0.03, 0.03, 0.03, 0.42 and 0.03 μg/ml, respectively. The concentration ranges in the low and high DDT concentration groups which contained 75 respondents respectively were 0-3.69 and 3.74-82.09 μg/ml, respectively. In the single-factor analysis, the number (percentage) of those who consumed seafood " rarely" , "less than twice a week" , and " twice a week or more" was 15 (20.3%), 22 (29.7%), and 37 (50.0%), respectively, in the low concentration group, and 4(5.3%), 20(26.7% ), and 51(68.0% ) in the high concentration group (χ²=8.69, P=0.013). The results of the multivariate logistic regression analysis indicate that pregnant women who consume seafood less than twice a week, twice a week or more have higher peripheral blood DDT concentrations compared with those who rarely consume seafood. The OR (95% CI) values were 1.14 (1.08-1.21), 2.11 (1.55-2.85), respectively. Conclusion: The exposure level of pregnant women to DDTs in the Xiamen area is higher than that of women in other regions. High seafood intake is a risk factor for internal exposure to DDTs.

Characteristics of fertile somatic hybrids of G. hirsutum L. and G. trilobum generated via protoplast fusion

Fertile somatic hybrids between tetraploid upland cotton G. hirsutum L. cv. Coker 312 and wild cotton G. trilobum were generated by symmetric electrofusion. Comparisons of morphology, combined with flow cytometric, RAPD, SRAP and AFLP analyses confirmed the hybrid nature of the regenerated plants. The hybrids differed morphologically from the parent plants. Flow cytometric analysis showed that the hybrids had DNA similar in amount to the total combined DNA content of the two parents, and the use of molecular markers revealed that the hybrids contained genomic fragments from both fusion parents, further indicating the hybrid nature of the regenerated plants. The stability of the morphological features of the hybrids was examined in following generations. The hexaploid fusion plants showed strong photosynthesis and a high expression level of some photosystem-related genes. Our results suggest that novel traits may be incorporated in cotton breeding programs through the production of somatic hybrids and the backcrossing of these plants with elite cultivars.

[Localization of oncoprotein P21ras in the human liver cancer]

Using the human liver cancer DNA transfected NIH/3T3 cell line, the human N-ras oncogene and the over expression of the oncoprotein P21ras was demonstrated, BALB/C mice were immunized. The spleen cells from the immunized mice were fused with SP2/0 myeloma cells. After the HAT medium selection and screening, two hybridoma cell lines, SCI-Oncogema 1 and 2, were established. In the immunoprecipitation test, the molecular weight of the protein reacting to Oncogema 1 was 21,000. This M.W 21,000 protein possessed the capability to bind with GTP, i.e. the character of P21ras. These data indicate that the Oncogema 1 is the monoclonal antibody against P21ras. Using Oncogema 1, specimens from 6 liver cancer patients were studied by immunopathology. With ABC stain, it was observed that the malignant cells in all the samples showed dark staining; the P21ras revealed over expression. Although the staining was heterogeneous, it implied that the ras oncogene was involved in the carcinogenesis of these six samples. No over expression was seen in the normal liver cells even in those around the cancerous lesion. However, dysplastic cells were moderately stained which means that the ras oncogene was activated and P21ras over expressed in these cells. The results suggest that the ras oncogene and P21ras play an important role in the early stage of liver cancer carcinogenesis.