Sorption characteristics of phosphorus on marine sediments in the presence of black carbon derived from fly ash.

The sorption behavior of phosphorus on marine sediments in the presence of black carbon derived from fly ash (FC) was studied. For both the FC and sediment samples, the kinetic curves could be described by a two-compartment first order equation, and the isotherms fit the Freundlich and Langmuir models well. The high specific surface area with abundant acidic functional groups of FC promoted the sorption and make this process more irreversible. The effects were more significant with higher amount of FC added. After sorption, more significant increase in Ex-P, Fe/Al-P and CaP was found in the sediment with FC added, while the organic groups in FC rarely react with phosphorus to form OP. The pH of medium influenced the sorption character, and FC promoted the process significantly at pH < pHPZNPC. The sorption was endothermic with an increase in randomness. The presence of FC had little effects on the thermodynamic parameters.

Effective capping of dissolved sulfide generated in Ulva prolifera-rich marine sediments by iron-rich red soil.

Bloom-induced macroalgal enrichment on the seafloor can substantially facilitate dissolved sulfide (DS) production through sulfate reduction. The reaction of DS with sedimentary reactive iron (Fe) is the main mechanism of DS consumption, which however usually could not effectively prevent DS accumulation caused by pulsed macroalgal enrichment. Here we used incubations to investigate the performance of Fe-rich red soil for buffering of DS produced from macroalgae (Ulva prolifera)-enriched sediment. Based on our results, a combination of red soil additions (6.8 kg/m2) before and immediately after pulsed macroalgal deposition (455 g/m2) can effectively cap DS within the red soil layer. The effective DS buffering is mainly due to ample Fe-oxide surface sites available for reaction with DS. Only a small loss (4 %) of buffering capacity after 18-d incubation suggests that the red soil is capable of prolonged DS buffering in macroalgae-enriched sediments.

Overexpression of SmLAC25 promotes lignin accumulation and decreases salvianolic acid content in Salvia miltiorrhiza.

Laccase (LAC) is a blue multicopper oxidase that contains four copper ions, which is involved in lignin polymerization and flavonoid biosynthesis in plants. Although dozens of LAC genes have been identified in Salvia miltiorrhiza Bunge (a model medicinal plant), most have not been functionally characterized. Here, we explored the expression patterns and the functionality of SmLAC25 in S. miltiorrhiza. SmLAC25 has a higher expression level in roots and responds to methyl jasmonate, auxin, abscisic acid, and gibberellin stimuli. The SmLAC25 protein is localized in the cytoplasm and chloroplasts. Recombinant SmLAC25 protein could oxidize coniferyl alcohol and sinapyl alcohol, two monomers of G-lignin and S-lignin. To investigate its function, we generated SmLAC25-overexpressed S. miltiorrhiza plantlets and hairy roots. The lignin content increased significantly in all SmLAC25-overexpressed plantlets and hairy roots, compared with the controls. However, the concentrations of rosmarinic acid and salvianolic acid B decreased significantly in all the SmLAC25-overexpressed lines. Further studies revealed that the transcription levels of some key enzyme genes in the lignin synthesis pathway (e.g., SmCCR and SmCOMT) were significantly improved in the SmLAC25-overexpressed lines, while the expression levels of multiple enzyme genes in the salvianolic acid biosynthesis pathway were inhibited. We speculated that the overexpression of SmLAC25 promoted the metabolic flux of lignin synthesis, which resulted in a decreased metabolic flux to the salvianolic acid biosynthesis pathway.

Sorption and distribution performance of organophosphorus compound (Adenosine 5'-monophosphate)on marine sediments.

In this paper, the kinetics and thermodynamics of Adenosine 5'-monophosphate (AMP) sorption on the sediments obtained from the Yangtze River Estuary and adjacent areas were studied, in combination with the effects of the sediments' properties and media conditions. The kinetics curves could be described by a two-compartment first-order equation, and the equilibrium isotherms fitted well with the modified Langmuir and Freundlich models. The analysis of organic phosphorus (OP) fractions changes after sorption indicated that the contents of exchangeable or loosely sorbed PO increased most significantly. Higher organic matter (OM) of the sediments were favorable for the sorption ability. It was also found that the content of OP and OM in the sediments showed an obvious positive correlation, indicating that organic matter rather than Fe/Al oxides played an important role in the migration of OP in the Yangtze River estuary and its adjacent area. Temperature, salinity and pH of the media influenced the sorption of AMP significantly. Increase of temperature was of benefit to the sorption of AMP, which was a spontaneous and exothermic process according to the calculations of the thermodynamic parameters. The sorption capacity was higher at a moderate salinity in the range of our study. With the pH changing from 3 to 10, the sorption capacity exhibited as a "U-trend" curve.

Effect of black carbon on sorption and desorption of phosphorus onto sediments.

The sorption behavior of phosphorus onto sediment was investigated with the addition of BC derived from incomplete biomass combustion (PC). The sorption kinetic curves of phosphorus onto PC and sediment could be described by a two-compartment first order equation, and the sorption isotherms fit the Freundlich model well. With increasing amounts of PC added, the sorption capacity increased while the HI did not change much. The distribution of phosphorus forms showed that CaP (ACa-P plus DAP) constituted the highest fraction in the sediment samples. Throughout the sorption process, CaP and OP changed very little, but the Ex-P and FeP increased obviously, and the presence of PC made this increase more significantly. The high specific area and the presence of iron and aluminum, as well as the modification of the sediments surface properties, make the addition of PC be favorable for the sorption of phosphorus onto sediments.

GABRP regulates chemokine signalling, macrophage recruitment and tumour progression in pancreatic cancer through tuning KCNN4-mediated Ca2+ signalling in a GABA-independent manner.

BACKGROUND AND AIMS: Pancreatic ductal adenocarcinoma (PDAC) is a leading cause of cancer-related death worldwide. Neurotransmitter-initiated signalling pathway is profoundly implicated in tumour initiation and progression. Here, we investigated whether dysregulated neurotransmitter receptors play a role during pancreatic tumourigenesis. METHODS: The Cancer Genome Atlas and Gene Expression Omnibus datasets were used to identify differentially expressed neurotransmitter receptors. The expression pattern of gamma-aminobutyric acid type A receptor pi subunit (GABRP) in human and mouse PDAC tissues and cells was studied by immunohistochemistry and western blot analysis. The in vivo implications of GABRP in PDAC were tested by subcutaneous xenograft model and lung metastasis model. Bioinformatics analysis, transwell experiment and orthotopic xenograft model were used to identify the in vitro and in vivo effects of GABRP on macrophages in PDAC. ELISA, co-immunoprecipitation, proximity ligation assay, electrophysiology, promoter luciferase activity and quantitative real-time PCR analyses were used to identify molecular mechanism. RESULTS: GABRP expression was remarkably increased in PDAC tissues and associated with poor prognosis, contributed to tumour growth and metastasis. GABRP was correlated with macrophage infiltration in PDAC and pharmacological deletion of macrophages largely abrogated the oncogenic functions of GABRP in PDAC. Mechanistically, GABRP interacted with KCNN4 to induce Ca2+ entry, which leads to activation of nuclear factor κB signalling and ultimately facilitates macrophage infiltration by inducing CXCL5 and CCL20 expression. CONCLUSIONS: Overexpressed GABRP exhibits an immunomodulatory role in PDAC in a neurotransmitter-independent manner. Targeting GABRP or its interaction partner KCNN4 may be an effective therapeutic strategy for PDAC.

Targeting Purinergic Receptor P2Y2 Prevents the Growth of Pancreatic Ductal Adenocarcinoma by Inhibiting Cancer Cell Glycolysis.

PURPOSE: Extensive research has reported that the tumor microenvironment components play crucial roles in tumor progression. Thus, blocking the supports of tumor microenvironment is a promising approach to prevent cancer progression. We aimed to determine whether blocking extracellular ATP-P2RY2 axis could be a potential therapeutic approach for PDAC treatment. EXPERIMENTAL DESIGN: Expression of P2RY2 was determined in 264 human PDAC samples and correlated to patient survival. P2RY2 was inhibited in human PDAC cell lines by antagonist and shRNA, respectively, and cell viability, clonogenicity, and glycolysis were determined. RNA sequencing of PDAC cell line was applied to reveal underlying molecular mechanisms. Multiple PDAC mouse models were used to assess the effects of the P2RY2 inhibition on PDAC progression. RESULTS: P2RY2 was upregulated and associated with poor prognosis in PDAC. Activated P2RY2 by increased extracellular ATP in tumor microenvironment promoted PDAC growth and glycolysis. Further studies showed that the agonist-activated P2RY2 triggered PI3K/AKT-mTOR signaling by crosstalk with PDGFR mediated by Yes1, resulting in elevated expression of c-Myc and HIF1α, which subsequently enhanced cancer cell glycolysis. Genetic and pharmacologic inhibition of P2RY2 impaired tumor cell growth in subcutaneous and orthotopic xenograft model, as well as delayed tumor progression in inflammation-driven PDAC model. In addition, synergy was observed when AR-C118925XX, the selective antagonist of P2RY2 receptor, and gemcitabine were combined, resulting in prolonged survival of xenografted PDAC mice. CONCLUSIONS: These findings reveal the roles of the P2RY2 in PDAC metabolic reprogramming, suggesting that P2RY2 might be a potential metabolic therapeutic target for PDAC.

Overexpression of Rac GTPase Activating Protein 1 Contributes to Proliferation of Cancer Cells by Reducing Hippo Signaling to Promote Cytokinesis.

BACKGROUND & AIMS: Agents designed to block or alter cytokinesis can kill or stop proliferation of cancer cells. We aimed to identify cytokinesis-related proteins that are overexpressed in hepatocellular carcinoma (HCC) cells and might be targeted to slow liver tumor growth. METHODS: Using the Oncomine database, we compared the gene expression patterns in 16 cancer microarray datasets and assessed gene enrichment sets using gene ontology. We performed immunohistochemical analysis of an HCC tissue microarray and identified changes in protein levels that are associated with patient survival times. Candidate genes were overexpressed or knocked down with small hairpin RNAs in SMMC7721, MHCC97H, or HCCLM3 cell lines; we analyzed their proliferation, viability, and clone-formation ability and their growth as subcutaneous or orthotopic xenograft tumors in mice. We performed microarray analyses to identify alterations in signaling pathways and immunoblot and immunofluorescence assays to detect and localize proteins in tissues. Yeast 2-hybrid screens and mass spectrometry combined with co-immunoprecipitation experiments were used to identify binding proteins. Protein interactions were validated with co-immunoprecipitation and proximity ligation assays. Chromatin immunoprecipitation, promoter luciferase activity, and quantitative real-time polymerase chain reaction analyses were used to identify factors that regulate transcription of specific genes. RESULTS: The genes that were most frequently overexpressed in different types of cancer cells were involved in cell division processes. We identified 3 cytokinesis-regulatory proteins among the 10 genes most frequently overexpressed by all cancer cell types. Rac GTPase activating protein 1 (RACGAP1) was the cytokinesis-regulatory protein that was most highly overexpressed in multiple cancers. Increased expression of RACGAP1 in tumor tissues was associated with shorter survival times of patients with cancer. Knockdown of RACGAP1 in HCC cells induced cytokinesis failure and cell apoptosis. In microarray analyses, we found knockdown of RACGAP1 in SMMC7721 cells to reduce expression of genes regulated by yes-associated protein (YAP) and WW domain containing transcription regulator 1 (WWTR1 or TAZ). RACGAP1 reduced activation of the Hippo pathway in HCC cells by increasing activity of RhoA and polymerization of filamentous actin. Knockdown of YAP reduced phosphorylation of RACGAP1 and redistribution at the anaphase central spindle. We found transcription of the translocated promoter region, nuclear basket protein (TPR) to be regulated by YAP and coordinately expressed with RACGAP1 to promote proliferation of HCC cells. TPR redistributed upon nuclear envelope breakdown and formed complexes with RACGAP1 during mitosis. Knockdown of TPR in HCC cells reduced phosphorylation of RACGAP1 by aurora kinase B and impaired their redistribution at the central spindle during cytokinesis. STAT3 activated transcription of RACGAP in HCC cells. CONCLUSIONS: In an analysis of gene expression patterns of multiple tumor types, we found RACGAP1 to be frequently overexpressed, which is associated with shorter survival times of patients. RACGAP1 promotes proliferation of HCC cells by reducing activation of the Hippo and YAP pathways and promoting cytokinesis in coordination with TPR.

Aberrant upregulation of KLK10 promotes metastasis via enhancement of EMT and FAK/SRC/ERK axis in PDAC.

Pancreatic Ductal Adenocarcinoma (PADC) metastasis is the leading cause of morality of this severe malignant tumor. Proteases are key players in the degradation of extracellular matrix which promotes the cascade of tumor metastasis. As a kind of serine proteases, the kallikrein family performs vital function on the cancer proteolysis scene, which have been proved in diverse malignant tumors. However, the specific member of kallikrein family and its function in PDAC remain unexplored. In this study, by data mining of GEO datasets, we have identified KLK10 is upregulated gene in PDAC. We found that KLK10 was significantly overexpressed in tissues of pancreatic intraepithelial neoplasia (PanIN) and PDAC from Pdx1-Cre; LSL-KrasG12D/+ mice (KC) and Pdx1-Cre; LSL-KrasG12D/+; LSL-Trp53R172H/+ mice (KPC) by immunohistochemical analysis. Moreover, KLK10 is extremely elevated in the PDAC tissues, especially that from the PDAC patients with lymphatic and distant metastasis. Aberrant KLK10 expression is significantly correlated with poor prognosis and shorter survival by univariable and multivariable analysis. Functionally, knockdown of KLK10 observably inhibits invasion and metastatic phenotype of PDAC cells in vitro and metastasis in vivo. In addition, blockade of KLK10 attenuates epithelial-mesenchymal transition and activation of FAK-SRC-ERK signaling, which explains the mechanism of KLK10 in promoting metastasis. Collectively, KLK10 should be considered as a promising biomarker for diagnosis and potential target for therapy in PDAC.

CCBE1 promotes GIST development through enhancing angiogenesis and mediating resistance to imatinib.

Gastrointestinal stromal tumor (GIST) is the most major mesenchymal neoplasm of the digestive tract. Up to now, imatinib mesylate has been used as a standard first-line treatment for irresectable and metastasized GIST patients or adjuvant treatment for advanced GIST patients who received surgical resection. However, secondary resistance to imatinib usually happens, resulting in a major obstacle in GIST successful therapy. In this study, we first found that collagen and calcium binding EGF domains 1 (CCBE1) expression gradually elevated along with the risk degree of NIH classification, and poor prognosis emerged in the CCBE1-positive patients. In vitro experiments showed that recombinant CCBE1 protein can enhance angiogenesis and neutralize partial effect of imatinib on the GIST-T1 cells. In conclusion, these data indicated that CCBE1 may be served as a new predictor of prognosis in post-operative GIST patients and may play an important role in stimulating GIST progression.

[Diagnostic values of urinary netrin-1 and kidney injury molecule-1 for acute kidney injury induced by neonatal asphyxia].

OBJECTIVE: To investigate the values of urinary netrin-1 and kidney injury molecule-1 (KIM-1) in the early diagnosis of acute kidney injury (AKI) induced by neonatal asphyxia. METHODS: A total of 80 full-term neonates with asphyxia were enrolled (mild asphyxia: 34 neonates; severe asphyxia: 46 neonates). Forty normal full-term neonates were selected as the control group. Urinary samples were collected from the neonates in the three groups within 12 hours and 13-48 hours after birth. ELISA was applied to measure urinary levels of netrin-1 and KIM-1. Peripheral venous blood samples were also collected to measure serum creatinine (Scr) level. RESULTS: Compared with the control group, the asphyxia group had significantly higher urinary levels of netrin-1 and KIM-1 within 48 hours after birth and a significantly higher Scr level within 13-48 hours after birth (P<0.05). The neonates in the AKI group had significantly higher urinary levels of netrin-1 and KIM-1 and Scr level within 48 hours after birth than those in the non-AKI group (P<0.05). The areas under the receiver operating characteristic curve for urinary netrin-1 and KIM-1 levels within 12 hours after birth to predict AKI after asphyxia were 0.878 (95% CI: 0.775-0.981; P<0.01) and 0.899 (95% CI: 0.829-0.969; P<0.01), respectively. Any two indicators of urinary netrin-1 level, urinary KIM-1 level, and Scr level within 12 hours after neonatal asphyxia had a positive correlation (P<0.05). CONCLUSIONS: Urinary netrin-1 and KIM-1 levels increase significantly when neonates with asphyxia develop AKI. Urinary netrin-1 and KIM-1 can be used as indicators for the early diagnosis of AKI after asphyxia.

Overexpressed EDIL3 predicts poor prognosis and promotes anchorage-independent tumor growth in human pancreatic cancer.

Epidermal Growth Factor-like repeats and Discoidin I-Like Domains 3 (EDIL3), an extracellular matrix (ECM) protein associated with vascular morphogenesis and remodeling, is commonly upregulated in multiple types of human cancers and correlates with tumor progression. However, its expression pattern and underlying cellular functions in pancreatic ductal adenocarcinoma (PDAC) remain largely unexplored. In current study, we observed that expression of EDIL3 was significantly up-regulated in PDAC compared with normal controls in both cell lines and clinical specimens. In addition, elevated EDIL3 expression was positively correlated with patients' TNM stage and T classification. Kaplan-Meier analysis indicated that high EDIL3 expression was significantly associated with shorter overall survival times in PDAC patients. Multivariate Cox regression analysis confirmed EDIL3 expression, age, lymph node metastasis and histological differentiation as independent prognostic factors in PDAC. Knockdown of EDIL3 showed no significant influence on cell viability, migration, invasion and starvation-induced apoptosis, but compromised anoikis resistance and anchorage independent tumor growth of PDAC cells. Meanwhile, treatment with recombinant EDIL3 protein markedly promoted anoikis resistance and anchorage independent tumor growth. Mechanistically, we demonstrated that altered protein expression of Bcl-2 family might contribute to the oncogenic activities of EDIL3. In conclusion, this study provides evidences that EDIL3 is a potential predictor and plays an important role in anchorage independent tumor growth of PDAC and EDIL3-related pathways might represent a novel therapeutic strategy for treatment of pancreatic cancer.

Synthesis and antioxidant activity of hydroxylated phenanthrenes as cis-restricted resveratrol analogues.

Five hydroxylated phenanthrenes as "cis-configuration-fixed" resveratrol analogues differing in the number and position of the hydroxyl groups were designed and synthesized. Their antioxidant activity was studied by ferric reducing antioxidant power, 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging, and DNA strand breakage-inhibiting assays, corresponding to their electron-donating, hydrogen-transfer and DNA-protecting abilities, respectively. In the above assays, their activity depends significantly on the number and position of the hydroxyl groups, and most of them are more effective than resveratrol. Noticeably, compound 9b (2,4,6-trihydroxyl phenanthrene) with the same hydroxyl group substitutions as resveratrol, is superior to the reference compound, highlighting the importance of extension of the conjugation over multiple aromatic-rings. Similar activity sequences were obtained in different experimental models, but the appreciable differences could contribute detailed insights into antioxidant mechanisms. Based on these results, the hydroxylated phenanthrenes may be considered as a novel type of resveratrol-directed antioxidants.

CuII ions and the stilbene-chroman hybrid with a catechol moiety synergistically induced DNA damage, and cell cycle arrest and apoptosis of HepG2 cells: an interesting acid/base-promoted prooxidant reaction.

Development of potential cancer treatment strategies by using an exogenous reactive oxygen species (ROS)-generating agent (prooxidant) or redox intervention, has attracted much interest. One effective ROS generation method is to construct a prooxidant system by polyphenolic compounds and Cu(II) ions. This work demonstrates that Cu(II) and the stilbene-chroman hybrid with a catechol moiety could synergistically induce pBR322 plasmid DNA damage, as well as cell cycle arrest and apoptosis of HepG2 cells. Additionally, an interesting acid/base-promoted prooxidant reaction was found. The detailed chemical mechanisms for the reaction of the hybrid with Cu(II) in acid, neutral and base solutions are proposed based on UV/Vis spectral changes and identification of the related oxidative intermediates and products.

Extraordinary radical scavengers: 4-mercaptostilbenes.

In the past decade, there was a great deal of interest and excitement in developing more active antioxidants and cancer chemoprevention agents than resveratrol, a naturally occurring stilbene. In this work, eight resveratrol-directed 4-mercaptostilbenes were constructed based on the inspiration that thiophenol should be a stronger radical scavenger than phenol, and their reaction rates with galvinoxyl (GO(.)) and 2,2-diphenyl-1-picrylhydrazyl (DPPH(.)) radicals in methanol and ethyl acetate were measured by using stopped-flow UV/Vis spectroscopy at 25 °C. Kinetic analysis demonstrates that 4-mercaptostilbenes are extraordinary radical scavengers, and the substitution of the 4-SH group for the 4-OH group in the stilbene scaffold is an important strategy to improve the radical-scavenging activity of resveratrol. Surprisingly, in methanol, some of the 4-mercaptostilbenes are 10(4)-times more active than resveratrol, dozens of times to hundreds of times more effective than known antioxidants (α-tocopherol, ascorbic acid, quercetin, and trolox). The detailed radical-scavenging mechanisms were discussed based on acidified-kinetic analysis. Addition of acetic acid remarkably reduced the GO(.) and DPPH(.) radical-scavenging rates of the 4-mercaptostilbenes in methanol, a solvent that supports ionization, suggesting that the reactions proceed mainly through a sequential proton loss electron transfer mechanism. In contrast, an interesting acid-promoted kinetics was observed for the reactions of the 4-mercaptostilbenes with DPPH(.) in ethyl acetate, a solvent that weakly supports ionization. The increased ratio in rates is closely correlated with the electron-rich environment in the molecules, suggesting that the acceleration could benefit from the contribution of the electron transfer from the 4-mercaptostilbenes and DPPH(.). However, the addition of acetic acid had no influence on the GO(.)-scavenging rates of the 4-mercaptostilbenes in ethyl acetate, due to the occurrence of the direct hydrogen atom transfer. Our results show that the radical-scavenging activity and mechanisms of 4-mercaptostilbenes depends significantly on the molecular structure and acidity, the nature of the attacking radical, and the ionizing capacity of the solvent.

Synthesis and biological evaluation of hydroxylated 3-phenylcoumarins as antioxidants and antiproliferative agents.

Based on the observed biological activities of coumarins and resveratrol, we synthesized fourteen hydroxylated 3-phenylcoumarins (stilbene-coumarin hybrids) including six novel ortho-hydroxy-methoxy substituted derivatives, 1-14, by Perkin reaction. We characterized these compounds concerning their antioxidant activity against 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH)-induced pBR322 DNA strand breakage, and their antiproliferative effects on human promyelocytic leukemia HL-60 and human lung adenocarcinoma epithelial A549 cells. Structure-activity relationship information suggests that the introduction of ortho-hydroxy-methoxy groups and ortho-dihydroxy groups on the aromatic A ring could efficiently improve antiproliferative activity. Interestingly, a new derivative, 6-methoxy-7-hydroxy-3-(4'-hydroxyphenyl)coumarin, 9, behaved as a poor antioxidant but appeared to be the most potent antiproliferative agent among the compounds examined, and this activity was mediated by deregulation in cell cycle and induction of apoptosis.

[Multi-factor analysis of radiation-induced esophagitis in three-dimensional conformal radiotherapy for non-small cell lung cancer].

OBJECTIVE: To explore the clinical and physical factors that might give rise to radiation-induced esophagitis in three-dimensional conformal radiotherapy for non-small cell lung cancer. METHODS: To collect the clinical and physical records and follow-up information of 106 NSCLC patients without undergoing surgery in our hospital. χ(2) test, linear tendency test and analysis of variance were employed to analyze the relationship between occurrence of radiation-induced esophagitis and clinical and physical treatment. Logistic analysis was also used for multivariate analysis. RESULTS: Among the 47 cases of radiation-induced esophagitis, 31 cases were of grade I, 11 of grade II, 5 of grade III, and with a total occurrence rate of 44.3% (47/106). Radiation-induced esophagitis was correlated with Karnofsky scores, radiation sensitization and tumor location (χ(2) = 11.30, 8.45, 7.67, P < 0.05). Radiation-induced esophagitis was correlated with the length of irradiated esophagus and average dose of irradiated esophagus (F = 20.82, 83.08, P < 0.001). With the increase of the irradiated volume percentage from V20, V30, V40 up to V50, the occurrence rate of radiation-induced esophagitis was also increased, almost with a linear trend (P < 0.05). Application of all the above factors to logistic model indicated that radiation sensitization,length of irradiated esophagus, average dose and V50 were all statistically significant foactors in the occurrence of radiation-induced esophagitis (OR = 0.321, 2.850, 7.307 and 8.558, P < 0.05). CONCLUSIONS: Radiation sensitization,length of irradiated esophagus, average dose of irradiated esophagus and V50 are independent factors in the occurrence of radiation-induced esophagitis. V50 is of greater importance in the judgement of occurrence of radiation-induced esophagitis.

[Influence of SDBS on sorption behaviors of heavy oil on Jiaozhou Bay sediment].

Sorption behavior of heavy oil onto Jiaozhou Bay sediment in the presence of anionic surfactant sodium dodecylbenzene sulfonate (SDBS) in artificial seawater was studied. Batch method was used to investigate the kinetic and thermodynamic behaviors. The results showed that the sorption rate and sorption capacity increased with the increasing initial concentration of SDBS. The sorption rate equations could be described by the pseudo-second-order model. The sorption isotherms were in good agreement with the Freundlich model. Higher salinity and lower temperature of the medium were favorable to the process. In the temperature range of 283-308K, the values of thermodynamic parameters were estimated, such as the deltaG(theta), deltaH(theta), deltaS(theta) which had significantly negative values in the presence of SDBS than those without SDBS. The sorption process was a spontaneous and exothermic reaction, and the randomness was decreased during the process.