Circ_0003356 suppresses gastric cancer growth through targeting the miR-668-3p/SOCS3 axis

BACKGROUND

Circular RNAs (circRNAs) have attracted extensive attention as therapeutic targets in gastric cancer (GC). Circ_0003356 is known to be downregulated in GC tissues, but its cellular function and mechanisms remain undefined.

AIM

To investigate the role of circ_0003356 in GC at the molecular and cellular level.

METHODS

Circ_0003356, miR-668-3p, and SOCS3 expression were assessed via quantitative real time-polymerase chain reaction (qRT-PCR). Wound healing, EdU, CCK-8, flow cytometry and transwell assays were used to analyze the migration, proliferation, viability, apoptosis and invasion of GC cells. The subcellular localization of circ_0003356 was monitored using fluorescence in situ hybridization. The interaction of circ_0003356 with miR-668-3p was confirmed using RIP-qRT-PCR, RNA pull-down, and dual luciferase reporter assays. We observed protein levels of genes via western blot. We injected AGS cells into the upper back of mice and performed immunohistochemistry staining for examining E-cadherin, N-cadherin, Ki67, and SOCS3 expressions. TUNEL staining was performed for the assessment of apoptosis in mouse tumor tissues.

RESULTS

Circ_0003356 and SOCS3 expression was downregulated in GC cells, whilst miR-668-3p was upregulated. Exogenous circ_0003356 expression and miR-668-3p silencing suppressed the migration, viability, proliferation, epithelial to mesenchy-mal transition (EMT) and invasion of GC cells and enhanced apoptosis. Circ_0003356 overexpression impaired tumor growth in xenograft mice. Targeting of miR-668-3p by circ_0003356 was confirmed through binding assays and SOCS3 was identified as a downstream target of miR-668-3p. The impacts of circ_0003356 on cell proliferation, apoptosis, migration, invasion and EMT were reversed by miR-668-3p up-regulation or SOCS3 down-regulation in GC cells.

CONCLUSION

Circ_0003356 impaired GC development through its interaction with the miR-668-3p/SOCS3 axis.

[Summary and analysis of total auricle reconstruction in adult microtia patients]

Objective: To observe the clinical effect of auricle reconstruction in adult patients with microtia and summarize the experience. Methods: Clinical data of adult patients with microtia who underwent total auricle reconstruction using the modified Nagata's two stage for microtia reconstruction from June 2016 to June 2021 were analyzed. A total of 41 adult patients (42 ears) with microtia were enrolled, including 30 males and 11 females, with the median age at the time of surgery of 37 years. Autogenous costal cartilage was used as the auricular framework for all patients in this group. The first stage surgery was performed according to the modified Nagata's two stage for microtia reconstruction procedure,cartilage auricular framework carving was performed by different methods according to the ossification state of adult costal cartilage. Six months following the primary operation, ear elevation and cranioauricular angle formation, retroauricular facial flap transfer and medium-thick skin grafting were performed in the second stage. Results: All patients successfully completed two stage operation. During the follow-up of 3 months and 24 months, all the 41 patients were satisfied with the morphology of reconstructed auricle. Conclusion: According to the costal cartilage status of adult patients, different costal cartilage carving techniques can be used for total auricle reconstruction to obtain ideal surgical results.

[Intravenous infusion of methylene blue to visualize the ureter in laparoscopic colorectal surgery]

Objective: Intraoperative localization of the ureter can contribute to accurate dissection and minimize ureteral injury in colorectal surgery. We aim to summarize a single center's experience of fluorescence ureteral visualization using methylene blue (MB) and explore its visualization efficiency. Methods: This is a descriptive case-series-study. Clinical data of patients who had undergone laparoscopic colorectal surgery and fluorescence visualization of the ureter in the Gastrointestinal Surgery Department of Guangdong Provincial People's Hospital from March 2022 to May 2022 were retrospectively collected. Patients with incomplete surgery videos, renal insufficiency, or allergic reactions were excluded. MB was infused with 0.9% NaCl at 1.0 mg/kg in 100 mL of normal saline for 5 to 15 minutes during laparoscopic exploration. Imaging was performed using a device developed in-house by OptoMedic (Guangdong, China) that operates at 660nm to achieve excitation of MB. Clinical information, MB dosage, rate of successful fluorescence, time to fluorescence, operation time, blood loss, intraoperative blood oxygen levels, pathological staging, changes in renal function, and post-operative complications were retrospectively analyzed. Results: The study cohort comprised 27 patients (24 men and 3 women) with an average age of (60.25±16.95) years and an average body mass index of (21.72±3.42) kg/m². The dosage of MB was 0.3-1.0 mg/kg and the infusion time was 5-15 minutes. Fluorescence signals were detected in all patients. The median time to signal detection was 20 (range, 10 to 40) minutes after MB infusion. The range of intraoperative blood oxygen fluctuation averaged 2.5% (range, 0 to 7.0%). The median change in creatine concentration was -1.3 (range, -17.2 to 29.2) µmol/L. No patients had complications associated with use of MB. Fluorescence visualization of the ureter was very valuable clinically in two patients (thick mesentery, stage T4). Conclusion: MB is a safe and effective means of visualizing the ureter by fluorescence during laparoscopic colorectal surgery, especially when the procedure is difficult. MB in a dosage of less than 1 mg/kg can slowly infused for more than 5 minutes during laparoscopic exploration. During the infusion, attention must be paid to blood oxygen fluctuations.

[Investigation and analysis of occupational hazards in construction of power transmission and transformation project]

Objective: To investigate the occupational hazard factors and exposure levels of workers during the construction of power transmission and transformation projects. Methods: Analysis and identification of occupational hazard factors were carried out for typical construction process of 6 power transmission projects and 3 substation projects in September 2018. The on-site occupational health investigation was carried out to detect and analyze the exposure levels of workers to occupational hazard factors. Results: The time weighted average concentration (C(TWA)) of crushing workers exposed to silica dust and welders exposed to welding fume in substation projects were 2.72 and 14.03 mg/m(3), respectively. The 8 h equivalent sound level results of exposure noise of carpenters in power transmission projects and crushing workers, reinforcement workers, carpenters, scaffolders, road builders in substation projects were 87.9, 92.5, 87.1, 92.5, 93.0 and 90.2 dB (A) , respectively. The 4-hour time equal energy frequency weighted vibration acceleration of hand-transmitted vibration of bricklayer in power transmission projects, bricklayer, general worker 3, road builder 1 and road builder 2 of substation projects were 5.36, 5.21, 5.28, 10.71 and 5.22 m/s(2), respectively. The effective irradiance of electric welding arc light of welders' limbs in power transmission projects and substation projects were 401.19, 319.68 μW/cm(2), respectively. All of the above exceeded the requirements of occupational exposure limits. The occupational radiation levels and exposure limits of hazardous chemical factors met the requirements of each post. Conclusion: During the construction of power transmission and transformation projects, the exposure levels of occupational hazard factors in multiple posts exceed the standard. The main responsibility of employers for occupational disease prevention and control should be implemented, and targeted comprehensive measures should be taken to reduce the exposure levels of occupational hazard factors of workers.

Fibroblast growth factor-21 alleviates phenotypic characteristics of dry age-related macular degeneration in mice

Age-related macular degeneration (AMD) is the main cause of blindness in elderly individuals. As a metabolic regulator, fibroblast growth factor 21 (FGF-21) has been proven indicated to have an effect on wet AMD, but whether this cytokine has a therapeutic effect on dry AMD is unclear. The current study aimed to evaluate the preventive effects of FGF-21 against retinal degeneration in mice and provide mechanistic insights. FGF-21-/- mice were raised to 10 months of age. Then, the morphological changes in the retinal pigment epithelium (RPE)/choroid of the mice were observed by transmission electron microscopy (TEM), and iTRAQ was used to detect the variations in the protein profile. Next, FGF-21-/- and wild-type mice of the same age were fed hydroquinone to generate a dry AMD mouse model to examine whether exogenous FGF-21 can interfere with the occurrence and development of dry AMD. In vivo studies revealed that following FGF-21 knockout, there was an increase in the expression of complement in the RPE/choroid concomitant with the occurrence of dry AMD-like pathological changes. Furthermore, exogenous FGF-21 administration effectively reversed this phenomenon. FGF-21 also demonstrated strong anti-inflammatory effects in the RPE/choroid by inhibiting the NF-κB pathway. In conclusion, the present study demonstrates that FGF-21 treatment presents a novel therapeutic approach for the prevention and development of dry AMD by reducing complement.

[Interventional effect of asiaticosdide on rats exposed to silica dust]

Objective: To investigate the effect of asiaticoside for fibrosis in lung tissues of rats exposed to silica and to explore its possible mechanism. Methods: 144 SD male rats were randomly divided into control group, model group, positive drug control group, asiaticoside high-dose group, medium-dose group and low-dose group, each group included 24 rats. Rats in the control group were perfused with 1.0 ml of normal saline, and the other groups were given 1.0 ml 50 mg/ml SiO(2) suspension. Gavage of herbal was given from the next day after model establishment, once a day. Rats in the positive drug control group were administration with 30 mg/kg tetrandrine and rats in the low-dose group, medium-dose group and high-dose group were given 20 mg/kg, 40 mg/kg and 60 mg/kg asiaticoside for fibrosis respectively. Rats in the control group and the model group were given 0.9% normal saline. The rats were sacrificed in on the 14th, 28th and 56th day after intragastric administration and collect the lung tissues to detect the content of hydroxyproline, TGF-β(1) and IL-18, observe the pathological changes of the lung tissues by HE and Masson staining and determine the expressions of Col-I, a-SMA, TGF-β in lung tissues by Western Blot. Results: On the 14th day, 28th day and 56th day after model establishment, the lung tissues of rats in the model group showed obvious inflammatory response and accumulation of collagen fibers, and the degree of inflammation and fibrosis increased with time. The intervention of asiaticoside could effectively inhibit the pathological changes of lung tissues. The contents of hydroxyproline, IL-18 and TGF-β1 in lung tissues of model group were higher than those in the control group (P<0.05) , while the level of hydroxyproline, IL-18 and TGF-β1 in asiaticoside groups were significantly decreased, and the difference was statistically signicant (P<0.05) . Compared with the control group, the expression levels of Col-I, TGF-β1and α-SMA in lung tissue of model group were increased (P<0.05) , while the expression level of Col-I, TGF-β1 and α-SMA were decreased after the intervention of asiaticoside, and the difference was statistically signicant (P<0.05) . Conclusion: Asiaticoside can inhibit the increase of Col-I, TGF-β1 and α-SMA content in the SiO(2)-induced lung tissues of rats, reduce the release of TGF-β1 and IL-18 inflammatory factors in lung tissue, and then inhibit the synthesis and deposition of extracellular matrix in rat lung tissue, and improve silicosis fibrosis.

Quantitative Expression of RNA from Frozen Organs and Formaldehyde-fixed and Paraffin-embedded Tissues

Abstract

Objective Quantitative analysis and comparison of the expression of ribonucleic acid （RNA） from frozen organs and formaldehyde-fixed and paraffin-embedded （FFPE） tissues. Methods Frozen specimens of human brain, myocardium and liver tissues as well as FFPE samples at different postmortem intervals were collected and mass concentration of RNA was extracted and detected. Reverse transcription-quantitative polymerase chain reaction （RT-qPCR） technology was used to analyze the amplification efficiency and relative expression of each RNA marker. Results The mass concentration and integrity of RNA extracted from FFPE samples were relatively low compared with frozen specimens. The amplification efficiency of RNA markers was related with RNA species and the length of amplification products. Among them, glyceraldehyde-3-phosphate dehydrogenase （GAPDH） and β-actin （ACTB） with relatively long amplification products failed to achieve optimal amplification efficiency, whereas 5S ribosomal RNA （5S rRNA） achieved ideal amplification efficiency and showed quite stable expression across various tissues, therefore it was chosen as internal reference marker. The expression quantity of GAPDH and ACTB in frozen specimens with longer postmortem intervals and in FFPE samples with relatively long amplification products was decreased. The expressions of tissue-specific microRNAs （miRNAs）, GAPDH and ACTB with relatively short amplification products had consistency in the same tissues and FFPE samples. Conclusion Through standardizing the RT-qPCR experiment, selecting the appropriate RNA marker and designing primers of appropriate product length, RNA expression levels of FFPE samples can be accurately quantified.

[Effect of microRNA-27a-3p on proliferation, apoptosis and cell cycle of hepatoma cells]

Objective: To investigate the effect of miR-27a-3p on proliferation, apoptosis and cell cycle of hepatoma cells. Methods: A quantitative real-time polymerase chain reaction (qPCR) was used to detect differential expression of miR-27a-3p in normal hepatic epithelial cells (L02) and hepatoma cells (HepG2 and PLC). Cell experiment was divided into four groups: HepG2 overexpression cells, Mi-27a-3p overexpression group (Mi-27a) and negative control group (Mi-Con); PLC knockdown cells, Mi-27a-3p knockdown group (Mi-inhibitor-27a) and negative control group (Mi-inhibitor-Con). The expression of microRNA-27a-3p in each group after transfection was detected by qPCR analysis. MTT assay was used to detect the cell proliferation. Flow cytometry was used to detect the apoptosis and cell cycle. One-way ANOVA was used for multiple comparisons, and t-test was used to compare two groups. Results: qPCR results showed that the expression levels of miR-27a-3p in L02, HepG2 and PLC increased sequentially, and the relative expression levels were 1.07 ± 0.04, 4.81 ± 0.64 and 11.31 ± 0.92, respectively (P < 0.05). MTT assay showed that the cell viability of HepG2 cells transfected with miR-27a-3p overexpression plasmid was significantly decreased compared with the negative control group (P < 0.05). The apoptosis assay showed that the apoptosis rate of miR-27a-3p overexpression group was higher than the negative control group (P < 0.05). The cell cycle results showed that the proportion of S phase cells in the miR-27a-3p overexpression cell group was significantly lower than the negative control group (P < 0.05). Furthermore, microRNA-27a-3p knockdown validation in PLC cells showed that MTT, apoptosis and cell cycle tests results were opposite to the results of HepG2 overexpression cells, and the differences were statistically significant (P < 0.05). Conclusion: miR-27a-3p can significantly inhibit the proliferation of hepatoma cells, promote cell apoptosis, alter the cell cycle distribution, and may become a potential target in hepatocellular carcinoma therapy.

[Predictive study on recurrence of chronic sinusitis with nasal polyps by tissue eosinophils and sinus CT]

Objective: To investigate the correlation between postoperative recurrence and clinical parameters in patients with chronic rhinosinusitis with nasal polyps (CRSwNP), and to study predicitve value of total scores of eosinophils (EOS) and sinus CT for postoperative recurrence. Methods: A retrospective analysis of 264 patients with CRSwNP who were admitted to the First Affiliated Hospital of Wenzhou Medical University from June 2013 to December 2015 was performed. The patient was subjected to a visual analogue scale (VAS) score, a skin prick test, a peripheral blood cell count, a sinus CT score, and a nasal polyp EOS count. All patients underwent endoscopic surgery and were followed up for at least 2 years. The demographic characteristics of the nasal polyps recurrence group and the non-recurrence group were compared with other clinical indicators. Quantitative data were compared by t test or Mann-Whitney U test, qualitative data were compared by chi-square test, and Logistic regression analysis was used for Logistic regression analysis. The risk factors for recurrence were assessed. The best cut-off value was determined by using the receiver operating characteristic (ROC) curve. The predictive value of the parameters was determined by area under curve (AUC). The difference was statistically significant at P<0.05. Results: The recurrence rate of the study patients was 43.56% (115/264). Sex, olfactory VAS score, total sinus CT score, peripheral blood neutrophil ratio, peripheral blood EOS absolute value and proportion, and tissue EOS absolute value and proportion were associated with postoperative recurrence of nasal polyps (χ(2)=5.241, t=-3.146, t=-7.441, χ(2)=180.617, t=-5.313, χ(2)=100.067, t=-7.471, χ(2)=258.916, all P<0.05), and the tissue EOS ratio and total sinus CT scores have higher predictive value for recurrence of nasal polyps (AUC values were 0.793, 0.767, respectively, all P<0.001). With the EOS ratio of nasal polyps >0.032, the sensitivity of predicting recurrence was 83.48%, the specificity was 56.38%. With the total score of sinus CT>15, the sensitivity of predicting recurrence was 51.30% and the specificity was 87.25%. The combined sensitivity of predictive recurrence was 92.00% and the specificity was 49.20%. Conclusion: The percentage of EOS in nasal polyps and the total score of sinus CT in patients with CRSwNP have better predictive diagnostic value for recurrence of nasal polyps.

[Protective effect and mechanism of tHBQ on acute silica dust exposure in rats]

Objective: To study the protective effects and possible mechanisms of tBHQ in rats exposed to acute silicadust. Methods: Male Wistar rats without specific pathogen SPF were randomly divided into control group、model group and intervention group, 32 rats for each group. Rats in the model group and the intervention group were treated with a single non exposed tracheal dust method to establish the rats exposed to silica model. The intervention group was intervened with 1% tBHQ solution, once a day. Each group 8 rats were sacrificed at 3,14,28,60d, respectively.The contents of IL-1,TNF-α, HYP,TGF-β in the lung tissue of rats were determined by enzyme linked immunosorbent assay(ELISA), the contents of MDA and the GSH-PX activity in lung tissue and serum of rats were determined by colorimetry. Results: Compared with the control group, the contents of IL-1 in the lung tissue of the model group and the intervention group at each time point increased with time, the contents of IL-1 of model group reached the maximum at 60d, the contents of IL-1 in intervention group reached the maximum at 28d(P<0.05), except 3 d. Compared with the control group, the contents of TGF-β and HYP in the lung tissue of the model group and the intervention group at 28 and 60 d increased with time and reached the maximum at 60d(P<0.05). Compared with the model group at each time point, the contents of IL-1, TGF-β, HYP in the intervention group were lower than those in the model group(P<0.05). Compared with the control group, the contents of MDA in lung tissue and serum of rats in model group and intervention group at different time points increased with time(P<0.05). Compared with the control group,the activity of GSH-PX in serum and lung tissue of rats in model group and intervention group decreased with time,there was no significant difference in 3d(P<0.05), compared with the control group, the activity of GSH-PX in the lung and serum tissue of in-tervenetion group was higher than model group except the 3d(P<0.05). Conclusion: The intervention of tBHQ can alleviate oxidative stress in rats exposed to silica dust to some extent, improve the antioxidant capacity of the body, and reduce the contents of IL-1, TNF-α, TGF-β,HYP in lung tissue,it has acertain impediment and inhibition effect on the inflammation and fibrosis caused by acute silica dust exposure.

Surgical management of 142 cases of split cord malformations associated with osseous divide

OBJECTIVES

To investigate the key surgical points in treating split cord malformations associated with osseous divide and scoliosis (SCM-OD-S).

MATERIALS AND METHODS

The surgical options and methods of a total of 142 SCM-OD-S cases were retrospectively analyzed, and the surgical precautions and imaging diagnosis were also discussed.

RESULTS

The 142 patients were performed osseous divide resection plus dural sac molding, which achieved good results and no serious complication such as spinal cord and nerve injury occurred; certain symptoms such as urination-defecation disorders, muscle strength subsidence, Pes Cavus, and toe movement disorder in partial patients achieved various degrees of relief, and it also created good conditions for next-step treatment against scoliosis.

CONCLUSIONS

The diagnosis of SCM-OD mainly depended on imaging inspection, routine magnetic resonance imaging (MRI) combined with computed tomography (CT) 3D reconstruction, which can comprehensively evaluate the types and features of diastematomyelia as well as other concomitant diseases. SCM alone needed no treatment, but surgery will be the only means of treating SCM-OD. Intraoperatively removing osseous divide step-by-step, as well as carefully freeing the spinal cord and remodeling the dural sac, can lay good foundations for relieving tethered cord, improving neurological symptoms, and further scoliosis orthomorphia, thus particularly exhibiting importance for the growth and development of adolescents.

[Correlation between RNA Expression Level and Early PMI in Human Brain Tissue]

OBJECTIVES

To explore the correlation between the expression levels of several RNA markers in human brain tissue and early postmortem interval （PMI）.

METHODS

Twelve individuals with known PMI （range from 4.3 to 22.5 h） were selected and total RNA was extracted from brain tissue. Eight commonly used RNA markers were chosen including β-actin, GAPDH, RPS29, 18S rRNA, 5S rRNA, U6 snRNA, miRNA-9 and miRNA-125b, and the expression levels were detected in brain tissue by real-time fluorescent quantitative PCR. The internal reference markers with stable expression in early PMI were screened using geNorm software and the relationship between its expression level and some relevant factors such as age, gender and cause of death were analyzed. RNA markers normalized by internal reference were inserted into the mathematic model established by previous research for PMI estimation using R software. Model quality was judged by the error rate calculated with estimated PMI.

RESULTS

5S rRNA, miRNA-9 and miRNA-125b showed quite stable expression and their expression levels had no relation with age, gender and cause of death. The error rate of estimated PMI using β-actin was 24.6%, while GAPDH was 41.0%.

CONCLUSIONS

5S rRNA, miRNA-9 and miRNA-125b are suitable as internal reference markers of human brain tissue owing to their stable expression in early PMI. The expression level of β-actin correlates well with PMI, which can be used as an additional index for early PMI estimation.

[Effect of radiation dose and dose rate on pulmonary fibrosis in mice]

OBJECTIVE

To study the effect of radiation dose and dose rate on radiation-induced pulmonary fibrosis in mice.

METHODS

Twenty-four C57BL/6 mice were randomly divided into a control group (n=6) and an irradiation group(n=18). The irradiation group was further assigned to 3 subgroups according to the whole lung radiation with 15 Gy at 400 cGy/min, 20 Gy at 400 cGy/min and 20 Gy at 100 cGy/min, while the control group received sham-irradiation. All mice were scanned with computed tomograph (CT) 20 weeks post-irradiation, and then they were sacrificed and lung tissues were collected. H&E staining, sirius red staining, lung fibrosis scored and hydroxyproline content analysis were used to assess lung fibrosis and collagen deposition. Real time PCR was used to measure the mRNA expression of type Ⅰ collagen. Immunohistochemical staining was used to detect the activatin and distribution of a-SMA(+) -myofibroblasts.

RESULTS

Compared to the control group, mice from irradiation groups exhibited significant pulmonary consolidation and collagen deposition.At the same dose rate, the higher irradiated dose used, the more severe pulmonary fibrosis was.On the other hand, with the same dose, the dose rate had less effect on pulmonary fibrosis.

CONCLUSION

The effect of radiation dose on the degree of pulmonary fibrosis in mice is more than effect of the dose rate.

Efficacy of video-assisted thoracoscopic surgery for 29 patients with tuberculosis-destroyed lung

BACKGROUND

Incompleteness of interlobar fissures and pleural adhesions, common in tuberculous destroyed lung (TDL), are among "technical contraindications" for video-assisted thoracoscopic surgery (VATS). The efficacy and safety of VATS in the treatment of TDL, has not yet been detailed in.

OBJECTIVE

The objective of the present study is to observe the efficacy and safety of VATS in the management of TDL.

METHODS

A retrospective review of anatomic lobectomy by VATS on 29 cases of TDL was performed in the Department of Thoracic Surgery of Wuhan Medical Treatment Center between October 2010 and October 2013.

RESULTS

All the 29 surgeries by VATS were successfully completed. No death case was reported. Operative duration of VATS was 75~400 min, with an average of 185.4 min; intraoperative amount of bleeding ranged 50 to 2300 ml, with an average of 575.6 ml; the incidence of postoperative complication was 21.4% (6/28). Postoperative complications occurred in 6 cases, among which there were 2 cases of persistent postoperative pulmonary air leak, 2 cases of pleural effusion, one case of thoracic hemorrhage and one case of arrhythmia complicated with left heart failure. There was one patient who was converted from VATS to open thoracic surgery half-way.

CONCLUSION

Our results have shown the efficacy, safety and a breakthrough in the "technical contraindications" of VATS in the management of TDL.

Abstract 5346: Identification of essential genes for the development of hepatitis B virus-associated hepatocellular carcinoma

Background and Aim: Hepatocellular carcinoma (HCC) is a highly lethal and prevalent cancer, posing a grave threat to human health globally. Hepatitis B virus (HBV) infection is considered as a major risk factor for this cancer, especially in the Asia-Pacific region. Unfortunately, the molecular mechanisms of hepatocarcinogenesis remain obscure, which hinders the development of effective therapies for the disease. In the present study, we attempted to elucidate the molecular details of HBV-induced hepatocarcinogenesis by investigating differentially regulated genes at multiple developmental stages of HCC in a HBV transgenic mouse model. Materials and Methods: The transgenic mice which overproduced HBV large envelope polypeptide in hepatocytes and developed liver tumors spontaneously were used in this study. To unravel transcriptomics dynamics underlying hepatocarcinogenesis, RNA prepared from livers of both transgenic and wild type mice of different ages (at months 2, 12, 18 and 19) were subjected to RNA sequencing. Selected target genes were first validated by quantitative PCR (qPCR) using a larger set of mouse liver tissues (n=96) collected from 8 time points. Clinical implications of the selected genes were then explored in a set of human liver samples comprising 18 normal, 29 cirrhosis and 96 pairs of HCC. RNA and protein expression levels were determined by qPCR, immunohistochemical staining and Western blotting, respectively. Results: Upon analysis of 20,209 gene transcripts, 2574 and 1035 transcripts were found to be up-regulated (≥2 folds) and down-regulated (≤2 folds) in tumors, respectively, when compared with the wild type controls. Among these, 133 most prominent genes that exhibited concordant differential expression throughout the stages of tumor progression were chosen for validation in mouse liver tissues. Correlation analysis showed a high correlation between RNA sequencing and qPCR data (r=0.7495; P&lt;0.0001), indicating a high validity of the data. Forty-six biologically informative genes were further validated in human liver samples. By Gene Ontology analysis, the target genes were revealed to play roles in a variety of biological processes including stress and inflammation responses, metabolic and apoptotic processes. Immunohistochemical staining and Western blotting demonstrated significant differential expression of these genes between HCC and non-tumorous livers. Statistical analyses revealed their significant correlation with clinicopathological parameters including venous infiltration, tumor size and overall survival, implicating their roles in hepatocarcinogenesis. Conclusion: This study has demonstrated a systematic strategy for identifying crucial genes for HBV-associated HCC, which may have profound implications in combating this deadly cancer.

Citation Format: CT Lam, ZF Yang, JC Lau, MN Ng, WC Yu, DW Ho, ST Fan. Identification of essential genes for the development of hepatitis B virus-associated hepatocellular carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5346. doi:10.1158/1538-7445.AM2014-5346

[Ecological risk assessment of hydropower dam construction on aquatic species in middle reaches of Lancang River, Southwest China based on ESHIPPO model]

An investigation was conducted on the phytoplankton, zooplankton, and fish at 8 sampling sections in the Manwan Reservoir before and after the construction of Xiaowan Hydropower Dam. The modified ESHIPPO model was applied to study the changes of the featured aquatic species, including endangered species, endemic specie, peis resource species, and native fish, aimed to make an ecological risk assessment of the dam construction on the aquatic species. The dam construction had definite ecological risk on the aquatic species, especially the endemic fish, in Langcang River, due to the changes of hydrological conditions. The endemic species including Bangia atropurpurea, Lemanea sinica, Prasiola sp., Attheyella yunnanensis, and Neutrodiaptomus mariadvigae were at high ecological risk, and thus, besides monitoring, protection measures were needed to be taken to lower the possibility of the species extinction. The widely distributed species of phytoplankton and zooplankton were at medium ecological risk, and protection measures besides monitoring should be prepared. Twelve kinds of native fish, including Barbodes huangchuchieni, Sinilabeo laticeps, Racoma lantsangensis, Racoma lissolabiatus, Paracobitis anguillioides, Schistura latifasciata, Botia nigrolineata, Vanmanenia striata, Homaloptera yunnanensis, Platytropius longianlis, Glyptothorax zanaensis, and Pseudecheneis immaculate, were at high ecological risk, and protection measures needed to be developed to prevent the possibility of the species loss and extinction.

[Lake eutrophication modeling in considering climatic factors change: a review]

Climatic factors are considered as the key factors affecting the trophic status and its process in most lakes. Under the background of global climate change, to incorporate the variations of climatic factors into lake eutrophication models could provide solid technical support for the analysis of the trophic evolution trend of lake and the decision-making of lake environment management. This paper analyzed the effects of climatic factors such as air temperature, precipitation, sunlight, and atmosphere on lake eutrophication, and summarized the research results about the lake eutrophication modeling in considering in considering climatic factors change, including the modeling based on statistical analysis, ecological dynamic analysis, system analysis, and intelligent algorithm. The prospective approaches to improve the accuracy of lake eutrophication modeling with the consideration of climatic factors change were put forward, including 1) to strengthen the analysis of the mechanisms related to the effects of climatic factors change on lake trophic status, 2) to identify the appropriate simulation models to generate several scenarios under proper temporal and spatial scales and resolutions, and 3) to integrate the climatic factors change simulation, hydrodynamic model, ecological simulation, and intelligent algorithm into a general modeling system to achieve an accurate prediction of lake eutrophication under climatic change.

Abstract 3862: The potential role of CD44 in liver regeneration

Background and Aim: Liver regeneration occurs after liver damage by ischaemia, hepatitis, or in hepatocellular carcinoma (HCC) patients receiving hepatic resection or liver transplantation. Understanding the molecular bases of this process will provide novel therapeutic approaches for patients with various liver diseases. Previous studies suggested the linkage between CD44, a multifunctional cell surface receptor, and liver regeneration. The detailed role of this receptor in liver regeneration, however, remained unclear. The present study aimed at elucidating the role of CD44 in liver regeneration. Materials and Methods: A mouse model of liver regeneration induced by partial hepatectomy (PH) was employed. Serum and liver tissues were collected at different time points after PH. ELISA was performed to measure hyaluronic acid (ligand for CD44) level in serum. Flow cytometry was done to characterize liver cell populations after PH. Liver regeneration was quantified by measurement of liver mass and by immunohistochemical staining for PCNA (a proliferation marker). Quantitative PCR was performed to compare gene expression pattern of 46 genes between CD45− CD44+ cells and their CD44− counterparts. Results: Firstly, serum hyaluronic acid level was elevated at the early stage of liver regeneration. Secondly, by flow cytometry, an increase in CD45− CD44+ cell population was found. Thirdly, immunohistochemical analysis revealed active hepatocyte proliferation during this period. Interestingly, the hepatectomy-induced cell proliferation was suppressed after treating mice with anti-CD44 antibody, suggesting a functional role of CD44 in liver regeneration. Lastly, dysregulation of genes involving in cell proliferation, angiogenesis, and metabolism of hyaluronic acid was disclosed in CD45− CD44+ cells. Conclusion: The present study indicated that CD44-mediated pathways are required for liver regeneration, which may have therapeutic implications in treating liver diseases, including HCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3862. doi:1538-7445.AM2012-3862

Emergy evaluation and economic analysis of three wetland fish farming systems in Nansi Lake area, China

Emergy and economic methods were used to evaluate and compare three fish production models, i.e., cage fish farming system, pond intensive fish rearing system and semi-natural extensive pond fish rearing system, in Nansi Lake area in China in the year 2007. The goal of this study was to understand the benefits and driving forces of selected fish production models from ecological and economic points of view. The study considered input structure, production efficiency, environmental impacts, economic viability and sustainability. Results show that the main difference among the three production systems was the emergy cost for fish feed associated with their feeding system, i.e., feeding on natural biomass such as plankton and grass or on commercial feedstock. As indicated by EYR, ELR and ESI, it can be clearly shown that the intensive production model with commercial feed is not a sustainable pattern. However, the point is that more environmentally sound patterns do not seem able to provide a competitive net profit in the short run. The intensive pond fish farming system had a net profit of 2.57E+03 $/ha, much higher than 1.27E+03 $/ha for cage fish farming system and slightly higher than 2.37E+03 $/ha for semi-natural fish farming system. With regard to the drivers of local farmer's decisions, the accessibility of land for the required use and investment ability determine the farmer's choice of the production model and the scale of operation, while other factors seem to have little effect. Theoretically, the development of environmentally sustainable production patterns, namely water and land conservation measures, greener feed as well as low waste systems is urgently needed, to keep production activities within the carrying capacity of ecosystems. Coupled emergy and economic analyses can provide better insight into the environmental and economic benefits of fish production systems and help solve the problems encountered during policy making.

A two-stage inexact joint-probabilistic programming method for air quality management under uncertainty

A two-stage inexact joint-probabilistic programming (TIJP) method is developed for planning a regional air quality management system with multiple pollutants and multiple sources. The TIJP method incorporates the techniques of two-stage stochastic programming, joint-probabilistic constraint programming and interval mathematical programming, where uncertainties expressed as probability distributions and interval values can be addressed. Moreover, it can not only examine the risk of violating joint-probability constraints, but also account for economic penalties as corrective measures against any infeasibility. The developed TIJP method is applied to a case study of a regional air pollution control problem, where the air quality index (AQI) is introduced for evaluation of the integrated air quality management system associated with multiple pollutants. The joint-probability exists in the environmental constraints for AQI, such that individual probabilistic constraints for each pollutant can be efficiently incorporated within the TIJP model. The results indicate that useful solutions for air quality management practices have been generated; they can help decision makers to identify desired pollution abatement strategies with minimized system cost and maximized environmental efficiency.

Integrated process control for recirculating cooling water treatment in the coal chemical industry

This work focused on the integrated process of the recirculating cooling water (RCW) treatment to achieve approximate zero emission in the coal chemical industry. The benefits of fractional and comprehensive RCW treatment were quantified and qualified by using a water and mass balance approach. Limits of cycle of concentrations and some encountered bottlenecks were used to ascertain set target limits for different water sources. Makeup water was mixed with water produced from reverse osmosis (RO) in the proportion of 6:4, which notably reduced salts discharge. Side infiltration, which settled down suspended solids, can reduce energy consumption by over 40%. An automated on-line monitoring organic phosphorus inhibitor feed maintains the RCW system stability in comparison to the manual feed. Two-step electrosorb technology (EST) instead of an acid feed can lead cycle of concentration of water to reach 7.0. The wastewater from RO, EST and filter was transferred into a concentration treatment system where metallic ions were adsorbed by permanent magnetic materials. Separation of water and salts was completed by using a magnetic disc separator. Applying the integrated process in a coal chemical industry, a benefit of 1.60 million Yuan annually in 2 years was gained and approximate zero emission was achieved. Moreover, both technical and economic feasibility were demonstrated in detail.

Investigating the spatial-temporal variation of nitrogen cycling in an urban river in the North China Plain

Urban rivers are essential in retaining nutrients, but little is known about nitrogen cycling in these rivers in semiarid areas. We measured chemical and isotopic compositions of ammonium (NH4(+)-N) and nitrate (NO3(-)-N) to investigate spatial-temporal variation of nitrogen cycling in the Fuhe River in the North China Plain. Nitrogen pollution in the river was mainly induced by extra NH4(+)-N inputs which come from the discharges of urban sewage and effluents of wastewater treatment plants in upstream. NH4(+)-N obtained from decomposing organic matter of sediments can diffuse into the overlying water. Intense nitrification then occurs at the terrestrial-aquatic interface. Due to less vegetation in spring and autumn, loss of NH4(+)-N is mainly caused by nitrification. In contrast, significant NH4(+)-N is absorbed by plants in summer. NO3(-)-N generated from nitrification can be denitrified during the study period. The highest NO3(-)-N loss (about 86.3%) was observed in summer. The contribution of NO3(-)-N loss due to denitrification is 44.6%. The remaining 55.4% is due to plant uptake. The results suggested that nitrogen cycling in the river is related to temperature and dry-wet cycles. And vegetation restoration along the river could benefit the incremental improvements to the aquatic ecosystem.

[Sources and transformations of nitrogen in the Fuhe River of the Baiyangdian Lake]

The sources and transformations of nitrogen in the Fuhe River were investigated by application of nitrogen isotope methods. The results showed that the values of delta15N in ammonium and nitrate were 1.35 per thousand-8.01 per thousand and -6.69 per thousand-8.36 per thousand, respectively. The industrial and municipal wastewater from the Baoding City contributed high ammonium to the river. In drying season, the processes of nitrification and denitrification were affected by both of water and sediment. In wetting season, ammonium was mainly absorbed by plants, and loss rate of nitrate was about 86.3%. The nitrate removal by denitrification reached 44.6%, whereas that by plant uptake was 55.4%, indicating the importance of vegetation in nitrogen removal. Thus, restoration of local vegetation in the river would be the key to relieve eutrophication in the lake.

Genetic polymorphisms of cytochrome P450 enzymes 2C9 and 2C19 in a healthy Mongolian population in China

We examined the distribution of major allelic variants of CYP2C9 and CYP2C19 in the Mongolian population of China and compared it with that of other populations. The polymorphisms of CYP2C9 (including the CYP2C9*1, CYP2C9*2 and CYP2C9*3 alleles) and CYP2C19 (including the CYP2C19*1, CYP2C19*2 and CYP2C19*3 alleles) were analyzed in 280 healthy unrelated Chinese Mongolian subjects, using a PCR-RFLP assay. The frequencies of CYP2C9*1, *2 and *3 alleles were 0.97, 0.00 and 0.03, respectively. The frequencies of CYP2C19*1, *2 and *3 alleles were 0.72, 0.24 and 0.04, respectively. We did not find any differences in the allelic distribution of these two genes between age groups. However, the genotype frequency of CYP2C9 *1/*3 was significantly higher in males than in females. Compared with other populations, we found that the allele frequencies of the CYP2C9*2 and CYP2C9*3 allelic variants in this Mongolian population of China were similar to those reported for other Asian populations, with significant differences compared to Caucasians and African-Americans.

Occurrence of aliphatic hydrocarbons in water, suspended particulate matter and sediments of Daliao River system, China

In August of 2005 a study was carried out to evaluate contamination of aliphatic hydrocarbons(AHc) in water, suspended particulate matter (SPM) and sediments from Daliao River system composed of the Hun River, Taizi River, and Daliao River in a heavy industrial area of northeast of China. The content of AHc ranged from 13.39 to 283.62 microg L(-1) in surface water, from 22.68 to 5,725.36 microg g(-1) in dry SPM, and from 61.37 to 229.42 microg g(-1) in dry sediments. High hydrocarbon levels were generally found in the areas associated with high anthropogenic impact and port activities. The calculated hydrocarbon indexes suggest that the stations with petrogenic sources and biogenic origin predominance would constitute aliphatic hydrocarbons for the river system. Hierarchical cluster analysis (HCA) of aliphatic hydrocarbons is correspondence with hydrocarbons indexes results.

Abstract 1305: The proangiogenic role of brain-derived neurotrophic factor in tumor development

Background and Aim: Hepatocellular carcinoma is a hypervascularized solid tumor which requires angiogenesis for its growth. Previous studies suggested that neurotrophins, such as brain-derived neurotrophic factor (BDNF), may serve as angiogenic factors. The involvement of BDNF in tumor angiogenesis, however, remains unclear. The present study aimed at elucidating the role of BDNF in regulating angiogenesis and tumor development. Materials and Methods: BDNF was overexpressed in a normal mouse endothelial cell line by transfection. The angiogenic properties, including proliferation, cell motility, invasiveness and cell survival, of the transfectants were subsequently assessed by MTT, cell migration, invasion and Annexin V labeling assays, respectively. Microarray analysis was performed to explore the BDNF-mediated angiogenic pathway. An in vivo cell co-injection model, using a mouse transformed hepatocyte cell line and BDNF transfectants, was used to study the role of BDNF in tumor development. Results: Firstly, overexpression of BDNF could promote endothelial cell proliferation, migration, invasion and survival. Secondly, the gene expression profiling data suggested that the BDNF-induced angiogenic effects could be attributed to a dozen of genes including transcription factors, cell adhesion molecules, chemokines and growth factors. Thirdly, the in vivo cell co-injection experiment showed that high BDNF-expressing endothelial cells are able to promote growth of tumors with significantly higher number of microvessels. On the other hand, knock-down of BDNF in a tumor-derived endothelial cell line by shRNAs impairs such tumor promoting effect. Conclusion: The present study showed that BDNF is crucial for tumor angiogenesis and may serve as a potential target for anti-angiogenic treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1305.

[Effects of land cover change on soil organic carbon and light fraction organic carbon at river banks of Fuzhou urban area]

By using Vario EL III element analyzer, the vertical distribution characteristics of soil organic carbon (SOC) and light-fraction organic carbon (LFOC) in the lawn, patch plantation, and reed wetland at river banks of Fuzhou urban area were studied in July 2007. For all the three land cover types, the SOC and LFOC contents were the highest in surface soil layer, and declined gradually with soil depth. Compared with reed wetland, the lawn and patch plantation had higher SOC and LFOC contents in each layer of the soil profile (0-60 cm), and the lawn had significantly higher contents of SOC and LFOC in 0-20 cm soil layer, compared with the patch plantation. After the reed wetland was converted into lawn and patch plantation, the SOC stock in the soil profile was increased by 94.8% and 72.0%, and the LFOC stock was increased by 225% and 93%, respectively. Due to the changes of plant species, plant density, and management measure, the conversion from natural wetland into human-manipulated green spaces increased the SOC and LFOC stocks in the soil profile, and improved the soil quality. Compared with the SOC, soil LFOC was more sensitive to land use/cover change, especially for those in 0-20 cm soil layer.

Brominated flame retardants, polychlorinated biphenyls, and organochlorine pesticides in bird eggs from the Yellow River Delta, North China

Concentrations of several persistent organohalogen compounds such as dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), decabromodiphenylethane (DBDPE), and polybrominated biphenyl 153 (PBB 153) were measured in eggs of six species of wild aquatic birds, one species of wild terrestrial bird, and two species of captive birds from North China. Among the contaminants measured, DDTs were the dominant compounds, HCHs and PCBs were in nearly the same concentration range, and PBDEs exhibited lower concentrations than other compound groups. The median concentrations of DDTs, HCHs, PCBs, and PBDEs in all avian species ranged from 21 to 11034, 5.5 to 623, 1.0 to 613, and 4.6 to 146 ng/g lipid wt, respectively. Median concentrations of DBDPE and PBB 153 in all avian species were in the range of not detectable (ND)-1.7 and ND-0.7 ng/g lipid wt, respectively. Significant differences among species in contaminant profiles and contaminant levels were found depending on their feeding habits, habitat, and migration. The captive birds had the lowest contaminant levels and entirely different congener profiles in PCBs and PBDEs from those of wild birds, which can be attributed to differences in dietary compositions and reproduction rates. Octa- to deca-BDEs contributed more to the total PBDEs in wild terrestrial and captive birds than in wild aquatic birds, except for one insectivorous species, possibly due to greater exposure to terrestrial food sources. Preliminary risk assessment suggests that there is no risk of a reduction in offspring survival in avian species from North China due to organohalogen compounds, except for dichlorodiphenyldichloroethylene (DDE), which would be expected to affect some proportion of the populations of several species of birds studied.

Therapeutic efficacy of Traditional Chinese Medicine 319 recipe on hepatic fibrosis induced by carbon tetrachloride in rats

BACKGROUND/AIMS

Hepatic fibrosis is a consequence of severe liver damage that occurs in many patients with chronic liver diseases. TCM 319 recipe is a Chinese Medicine formula which consists of six Chinese herbs. In this study, we investigated the anti-fibrotic efficacy and mechanisms of TCM 319 recipe.

METHODS

Hepatic fibrosis in rats was induced by carbon tetrachloride (CCl4). 34 male adult SD rats were allocated into five groups (group 1-concomitant CCl4 and TCM 319 recipe for 8 weeks; group 2-CCl4 for 4 weeks and then CCl4 and TCM 319 recipe for 4 weeks; group 3-CCl4 alone for 8 weeks; group 4-TCM 319 recipe only for 8 weeks; group 5-untreated controls). After 8 weeks of treatment, serum ALT assay, liver tissue histological examination and immunostaining were carried out to examine the liver function and fibrosis degree. The expression levels of platelet derived growth factor (PDGF-B), PDGF-Rbeta, and transforming growth factor-beta 1 (TGF-beta1) were measured by quantitative RT-PCR and western blot.

RESULTS

TCM 319 recipe reduced liver injury and attenuated hepatic fibrosis in group 1 compared with that in group 3. TCM 319 recipe suppressed the mRNA expression of tissue inhibitor of metalloproteinase 1 (TIMP-1). In addition, treatment with TCM 319 recipe significantly down-regulated mRNA expression of PDGF-B and PDGF-Rbeta, and it also suppressed protein expression of PDGF-Rbeta and TGF-beta1.

CONCLUSIONS

TCM 319 recipe extracts could attenuate hepatic fibrosis induced by CCl4 in rats. The anti-fibrotic effect of TCM 319 recipe is associated with the down-regulation of mRNA expression of TIMP-1, PDGF-B and PDGF-Rbeta, and with the suppression of protein expression of PDGF-Rbeta and TGF-beta1.

Inexact fuzzy-stochastic constraint-softened programming - A case study for waste management

In this study, an inexact fuzzy-stochastic constraint-softened programming method is developed for municipal solid waste (MSW) management under uncertainty. The developed method can deal with multiple uncertainties presented in terms of fuzzy sets, interval values and random variables. Moreover, a number of violation levels for the system constraints are allowed. This is realized through introduction of violation variables to soften system constraints, such that the model's decision space can be expanded under demanding conditions. This can help generate a range of decision alternatives under various conditions, allowing in-depth analyses of tradeoffs among economic objective, satisfaction degree, and constraint-violation risk. The developed method is applied to a case study of planning a MSW management system. The uncertain and dynamic information can be incorporated within a multi-layer scenario tree; revised decisions are permitted in each time period based on the realized values of uncertain events. Solutions associated with different satisfaction degree levels have been generated, corresponding to different constraint-violation risks. They are useful for supporting decisions of waste flow allocation and system-capacity expansion within a multistage context.

Bioleaching of chalcopyrite concentrate by a moderately thermophilic culture in a stirred tank reactor

A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainage samples collected from several chalcopyrite mines in China. Such mixed culture can be used to effectively extract copper from chalcopyrite. Furthermore, after being adapted to gradually increased concentration of chalcopyrite concentrate, the tolerance of the mixed culture to chalcopyrite concentrate was brought up to 80 g/L. The effects of several leaching parameters on copper recovery in stirred tank reactor also had been investigated. The results of the investigation show that it was possible to achieve a copper extraction rate of 75% in 44 days at a pulp density of 8%. The leaching rate of chalcopyrite concentrate tended to increase with dissolved total iron concentration. At low pH ranges, more microscopic counts of microorganisms were found in the solution. Furthermore, the analysis of leached residues indicates that the passivation of chalcopyrite concentrate was mainly due to a mass of jarosite and PbSO(4) on the mineral surface, other than the elemental sulphur layer. The bacterial community composition was analyzed by using Amplified Ribosomal DNA Restriction Analysis. Two moderately thermophilic bacteria species were identified as Leptospirillum ferriphilum and Acidithiobacillus caldus with abundance of 67% and 33% in the bio-pulp, respectively.

Modelling the depuration rates of polychlorinated biphenyls in Oncorhynchus mykiss with quantum chemical descriptors

Using quantum chemical descriptors and partial least squares regression, a quantitative structure-activity relationship (QSAR) model is developed for the depuration rate constants (log k(d)) of 62 polychlorinated biphenyls (PCBs) in juvenile rainbow trout (Oncorhynchus mykiss). The values of the cross-validated regression coefficient (Qcum(2)) and standard deviation (SD) are 0.655 and 0.05, respectively. The high cross-validated coefficient and low standard deviation indicate that the QSAR model is well predictive. In the QSAR model, the following six descriptors are highly significant: QH(+) (the most positive charge of a hydrogen atom), HOF (standard heat of formation), CCR (core-core repulsion), EE (electronic energy), alpha(2) (squared average molecular polarisability), and S (molecular surface area). The significant descriptors show that the depuration of PCBs in rainbow trout may be mainly attributed to the biota-water partitioning process, and the reactive activity of PCB molecules may play a subordinate role.

An integrated two-stage optimization model for the development of long-term waste-management strategies

In this study, an integrated two-stage optimization model (ITOM) is developed for the planning of municipal solid waste (MSW) management in the City of Regina, Canada. The ITOM improves upon the existing optimization approaches with advantages in uncertainty reflection, dynamic analysis, policy investigation, and risk assessment. It can help analyze various policy scenarios that are associated with different levels of economic penalties when the promised policy targets are violated, and address issues concerning planning for a cost-effective diversion program that targets on the prolongation of the existing landfill. Moreover, violations for capacity and diversion constraints are allowed under a range of significance levels, which reflect the tradeoffs between system-cost and constraint-violation risk. The modeling results are useful for generating a range of decision alternatives under various environmental, socio-economic, and system-reliability conditions. They are valuable for supporting the adjustment (or justification) of the existing waste-management practices, the long-term capacity planning for the city's waste-management system, and the identification of desired policies regarding waste generation and management.

[Study on the spectrum response of Brassica Campestris L leaf to the zinc pollution]

In the present paper, the spectrum response of Brassica Campestris L leaf to the stress of heavy metal zinc pollution was studied in three spectral rangess of the red edge position (680-740 nm), the visible spectrum (460-680 nm) and the near infrared spectrum (750-1000 nm). The results indicate that the Zn content in cabbage leaves increases and the chlorophyll level reduces with the increase in Zn concentration in soil. With the Zn content of Brassica Campestris L leaves increasing, the leaf spectral reflectivity in visible light (A1) and the range of red edge shift (S) ascends, the the leaf spectral reflectivity in the near infrared light (A2) decreases. The three indices of A1, A2 and S are fitted much linearly with the logarithm of zinc content in Brassica Campestris L leaves with the high squared regression coefficients of 0.942, 0.981 and 0.969 respectively. The regression models are reliable to estimate the zinc content in Brassica Campestris L leaves.

[Contamination characters of polycyclic aromatic hydrocarbons in Daliao River system of China]

With GC/MS, a quantitative study was made on the polycyclic aromatic hydrocarbons (PAHs) in the surface water and suspended particulates in Daliao River system, with their spatial distribution and sources investigated. The results showed that the total PAHs concentration ranged from 946.1 to 13 448.5 ng x L(-1) in surface water, and from 317.5 to 238 518.7 ng x g in suspended particulates. The PAHs concentration was decreased in the order of Taizi River > Daliao River > Hunhe River. The PAHs in surface water were dominated by 3-5 rings, while those in suspended particulates were dominated by 2 rings. The calculated ratios of selected PAHs suggested that the discharges from municipal, petrochemical and steel industrial wastewater, and the atmospheric fallout might be the important PAHs sources, and the contamination sources of PAHs were the mixture of petrogenic and pyrolytic inputs. In comparing with other river and marine systems in the world, Daliao River system had higher concentrations of PAHs in its surface water and suspended particulates, and thus, presented certain ecological risk.

[Study on the treatment of aromatic hydrocarbon containing wastewater by an anaerobic filter reactor under denitrifying condition]

With benzene, naphthalene and biphenyl as the model aromatic hydrocarbon, the treatment of aromatic hydrocarbon containing wastewater by an anaerobic filter (AF) reactor operated in continuous mode and under denitrifying condition were conducted. With glucose as the supplemented carbon, the influence of C/N ratio on the degradation of organic compounds was also investigated. Results showed that the AF reactor could degrade these aromatic hydrocarbons effectively under above mentioned conditions. When the influent COD concentration was 1 000 mg/L, and benzene, naphthalene and biphenyl concentration was 60 mg/L, the removal efficiency for COD and aromatic hydrocarbons was 90% and 84%, respectively. Benzene was more easily degraded than naphthalene and biphenyl under denitrifying condition. When C/N was in the range 5 - 30, benzene removal percentage was always at about 90% , and C/N ratio did not have obvious effect on the degradation of benzene. The degradation of naphthalene and biphenyl and total COD was greatly influenced by C/N. When C/N was 15, the highest removal percentage was achieved and it was 90%, 78% and 82% for COD, naphthalene and biphenyl, respectively.

Biodegradation of polycyclic aromatic hydrocarbons in the natural waters of the Yellow River: effects of high sediment content on biodegradation

The contamination of polycyclic aromatic hydrocarbons (PAHs) has become one of the major problems in the Yellow River of China. As the Yellow River is the most turbid large river in the world, it remains unknown to which extent the high suspended sediment content in the river may affect the fate and effect of PAHs. Here we report the effect of sediment on biodegradation of chrysene, benzo(a)pyrene and benzo(g,h,i)perylene with phenanthrene as a co-metabolism substrate in natural waters from the Yellow River. Biodegradation kinetics of the PAHs in the river water with various levels of sediment contents were studied in the laboratory by fitting with a biodegradation kinetics model for organic compounds not supporting growth. The results indicated that the biodegradation rates of PAHs increased with the sediment content in the water. When the sediment contents were 0, 4 and 10 g/l, the biodegradation rate constants of chrysene with the initial concentration of 3.80 microg/l were 0.053, 0.084 and 0.111 d(-1), respectively. Further studies suggested the enhanced biodegradation rate in the presence of sediment was caused by the following mechanisms: (1) the population of PAH-degrading bacteria in the water system was found to increase with the sediment content; the bacteria population on sediment phase was far greater than that on water phase during the cultivation process; (2) the sorption of PAHs on the sediment phase was well described by the dual adsorption-partition model. Although the sorption capacity of PAH per unit weight of sediment decreased with the increase of the sediment content, the amount of sorbed PAH increased with the sediment content; and, (3) the desorption of PAHs from the solid phase led to a higher concentration near the water-sediment interface. Since the bacteria were also attached to the interface, this resulted in an increased contact chance between the bacteria and PAHs.

[Studies of relationships between Cu pollution and spectral characteristics of TritiZnm aestivum L]

The effect of Cu pollution on the Cu uptake by wheat, the characteristics of chlorophyll concentration, and the visible-near infrared spectra were studied under the condition of solution culture, and the relationships among the three indices were discussed. The results indicate that the content of Cu in TritiZnm aestivum L. increases and the concentration of chlorophyll reduces with the increase of Cu in solution. The spectral characteristics also take on the disciplinary diversification (the spectral reflectivity ascended in the visible light band and decreased in the near infrared band; the range of red edge shift decreased) with the increase of Cu in solution.

QSPRs for the prediction of photodegradation half-life of PCBs in n-hexane

By partial least squares (PLS) regression analysis, a quantitative structure-property relationship (QSPR) model was developed for photodegradation half-life (t1/2) of polychlorinated biphenyls (PCBs) in n-hexane solution under UV irradiation. Quantum chemical descriptors computed by PM3 Hamiltonian were used as predictor variables. The cross-validated value for the optimal QSPR model was 0.589, indicating good predictive capability for log t1/2 values of PCBs in n-hexane. The QSPR results show that standard heat of formation (DeltaHf), total energy (TE), and molecular weight (Mw) have dominant effect on t1/2 values of PCBs in n-hexane. Increasing DeltaHf and TE values or decreasing Mw values of the PCBs leads to decrease of log t1/2 values. In addition, increasing the largest negative atomic charge on a carbon atom and dipole moment of the PCBs leads to decrease of log t1/2 values.

[Effect of particles on the photodegradation of PAHs in natural waters of the Yellow River]

Photodegradation of chrysene, benzo(a)pyrene and benzo(ghi)perylene in natural water of the Yellow River was studied using simulation sunlight. The effects of particulates on the photodegradation were explored. Several results arose from this study: (1) The photodegradation of PAHs can be fitted with first-order kinetics when no particulates exist in water system, and the first-order constant increase with the decrease of initial concentration of PAHs. The photodegradation rates of the three PAHs are related to their molecule absorption spectrum. (2) The presence of loess exerts two kinds of effects on the photodegradation of PAHs, which include the inner filter effects and the photosensitizing effects of humic substance in Loess. These two opposite effects lead to the difference of net effects among different contents of loess. When the loess contents are 0.1 g/L and 5.0 g/L, the presence of loess stimulates the photodegradation of chrysene, benzo(a)pyrene. When the loess content is 5.0 g/L, the presence of loess stimulates the photodegradation of benzo(ghi)perylene. In addition, the photodegradation of PAHs can be fitted with the second-order kinetics when there is loess in the water system. (3) The dissolvable humic substances in loess can accelerate the photodegradation of PAHs while the indissoluble part cannot. (4) Since the dissolvable humic substances in the suspended solids of the river have been dissolved in water, the addition of suspended solids to the water system can only cause the decrease of photodegradation rate of PAHs due to its inner filter effects, and the photodegradation rate decreases with the suspended solid content as a power exponent function.

[Calculation of environmental flows in river reaches based on ecological objectives]

Based on the identifying the ecological objectives, environmental flows in river reaches is calculated after the relation between parameters of objectives, and river discharges is determined. The ecological objectives are determined in a two step process: theobjective will be determined for the critical period of the year, then the temporal variation will be defined. Considering the compatibility between the different kinds of environmental flow requirements, the strictest objective is settled to be the ecological objectives for the critical period of the year. The temporal variation of the natural river discharge monthly is settled to be the temporal variation of ecological objectives. In the studies of the environmental flows in the river reaches downstream for Guanting reservoir in the Yongding River of Haihe River Basin, the requirements of velocities for spawning of the fish in April are regarded as the ecological objectives in the most critical period because this also is the period of highest water demand for irrigation. The relation between objectives and river discharge is identified using historical data at the river station. The results indicate that the minimum, medium and ideal lever of annual environmental flow requirements are 1.56 x 10(8) m3, 5.97 x 10(8) m3 and 11.02 x 10(8) m3, about 7.19%, 27.51% and 50.78 % of the natural river discharge respectively. The ratio of water requirements monthly should be 20 % in the flood period (Aug.) and be 20% in biological propagation period in spring (Apr. - Jun.).

Upstream-downstream cooperation approach in Guanting Reservoir watershed

A case study is introduced and discussed concerning water dispute of misuse and pollution between up- and down-stream parts. The relations between water usage and local industrial structures are analyzed. Results show it is important to change industrial structures of the target region along with controlling water pollution by technical and engineering methods. Three manners of upstream-downstream cooperation are presented and discussed based on the actual conditions of Guangting Reservoir watershed. Two typical scenarios are supposed and studied along with the local plan on water resources development. The best solution for this cooperation presents a good way to help the upstream developing in a new pattern of eco-economy.

Nitrification in natural waters with high suspended-solid content--a study for the Yellow River

In this research, the mechanism regarding the effects of suspended solids on nitrification in freshwater systems with high solid contents was examined. Experimental studies were conducted for natural water of the Yellow River under laboratory conditions. Nitrification kinetics was investigated in water systems with various levels of suspended-solid contents. The associated mechanisms were analyzed through investigation of the adsorption-desorption of ammonium nitrogen, the process of bacteria growth, and the feature of nitrification kinetics. The results indicated that the presence of suspended solids could accelerate the nitrification process. The nitrification rate would increase non-linearly with the increase of suspended-solid content. When the initial concentration of ammonia nitrogen was 12.70 mg/l in the water system, the ratios of half-time duration for nitrification would be 1.88:1.23:1 under suspended-solid contents of 0, 1.84 and 5.00 g/l, respectively. When the initial concentration of ammonia nitrogen was around 1.0 mg/l in the water system, the nitrification rates in systems with suspended-solid contents of 1.81 and 3.42 g/l would then be approximately 9 and 12 times that without suspended solids, respectively. The populations of nitrifying bacteria would rise with increasing suspended-solid content. The existence of suspended solids would increase the contact chances between bacteria and nitrogen, resulting in accelerated nitrification processes; this was manifested by the increased K(4) (tau(max)/K(S)) along with the raised suspended-solid contents while fitting nitrification kinetics with the growth-based logistic model. Since the amount of ammonium nitrogen adsorbed on suspended-solid surface was non-linearly proportional to the suspended-solid content, the nitrification rate was also non-linearly proportional to the suspended-solid content.

Projection pursuit cluster model and its application in water quality assessment

One of the difficulties frequently encountered in water quality assessment is that there are many factors and they cannot be assessed according to one factor, all the effect factors associated with water quality must be used. In order to overcome this issues the projection pursuit principle is introduced into water quality assessment, and projection pursuit cluster (PPC) model is developed in this study. The PPC model makes the transition from high dimension to one-dimension. In other words, based on the PPC model, multifactor problem can be converted to one factor problem. The application of PPC model can be divided into four parts: (1) to estimate projection index function Q(a -->); (2) to find the right projection direction a -->; (3) to calculate projection characteristic value of the i th sample z(i), and (4) to draw comprehensive analysis on the basis of z(i). On the other hand, the empirical formula of cutoff radius R is developed, which is benefit for the model to be used in practice. Finally, a case study of water quality assessment is proposed in this paper. The results showed that the PPC model is reasonable, and it is more objective and less subjective in water quality assessment. It is a new method for multivariate problem comprehensive analysis.

Influence of the Haizhou Open Pit Coal Mine on the atmospheric flow over Fuxin, China

The influence of the Haizhou Open Pit Mine on the atmospheric flow in nearby Fuxin City in China was analyzed with the aid of the steady-state Navier-Stokes equations. The finite element method was used to obtain numerical solutions to these equations. The results showed that the Haizhou Open Pit Coal Mine contributes to the turbulent flow in the Fuxin City and its surroundings. However, when compared with the climatic effects, the open pit mine has a relatively small impact on the atmospheric flow over Fuxin.