Removal efficiency, kinetic, and behavior of antibiotics from sewage treatment plant effluent in a hybrid constructed wetland and a layered biological filter.

Sewage treatment plant (STP) is the major point source of antibiotic contamination, yet the advanced treatment of antibiotic polluted STP effluent has not been given necessary attention. This study is conducted to evaluate the removal efficiency, kinetic, and behavior of sulfonamides, quinolones, tetracyclines, and macrolides antibiotics from STP effluent in a hybrid constructed wetland (HCW) and a layered biological filter (LBF) at different hydraulic loading rates (HLRs). The results showed that the removal efficiency of antibiotics in all the HLRs was ranked as follow: quinolones of HCW (70-95%) > macrolides of HCW (58-77%) > tetracyclines of both systems (59-67%) > quinolones of LBF (28-64%) > macrolides of LBF (13-25%) > sulfonamides of both systems (<0%). The optimal HLR is 1.0 m/day for quinolones and 2.0 m/day for tetracyclines-macrolides in the HCW, and 6.4 m/day for quinolones-tetracyclines in the LBF, respectively. Although HCW performed better on the removal of most antibiotics, LBF exhibited stronger total loading toleration and higher removal loading ability to antibiotics. Among them, quinolones were markedly removed by multiple effect of substrate adsorption, microbial anaerobic degradation, and photolysis in the HCW (planted), and by filter sorption and interception in the LBF (unplanted); adsorption is the dominant elimination approach for tetracyclines in both systems; plant uptake plays a significant role on the removal of macrolides in the HCW.

LTBP2 knockdown by siRNA reverses myocardial oxidative stress injury, fibrosis and remodelling during dilated cardiomyopathy.

AIM: Dilated cardiomyopathy (DCM) is characterised by left ventricular dilation and associated with systolic dysfunction. Recent evidence has reported the high expression of latent transforming growth factor beta binding protein 2 (LTBP2) in heart diseases, which may play a role in regulating multiple biological functions of myocardial cells. Thus, this study set out to investigate the molecular mechanism and effects of LTBP2 in myocardial oxidative stress injury, fibrosis and remodelling in a rat model of DCM, with the involvement of NF-κB signalling pathway. METHODS: The rat model of DCM was treated with si-LTBP2 and/or activator of NF-κB signalling pathway to examine the haemodynamic indexes, cardiac functions, oxidative stress injury, fibrosis and remodelling. Moreover, in vitro experiments were conducted to verify the regulatory role of LTBP2 and NF-κB signalling pathway in DCM. RESULTS: LTBP2 was up-regulated in DCM rats. After LTBP2 was knocked down, haemodynamic indexes, HW/BW ratio, collagen volume fraction (CVF) level, positive expression of LTBP2, levels of reactive oxygen species (ROS), malondialdehyde (MDA), interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), tumour necrosis factor beta 1 (TGF-ß1) and brain natriuretic peptide (BNP) were all decreased. Meanwhile, levels of LTBP2, Col-I, Col-III, p65 and p52 were also reduced, while HW, BW and levels of SOD and TAOC were increased. In contrast, activation of NF-κB signalling pathway reversed effects of LTBP2 gene silencing. These findings were confirmed by in vivo experiments. CONCLUSIONS: LTBP2 silencing can attenuate myocardial oxidative stress injury, myocardial fibrosis and myocardial remodelling in DCM rats by down-regulating the NF-κB signalling pathway.

Synergistic oxidation of Bisphenol A in a heterogeneous ultrasound-enhanced sludge biochar catalyst/persulfate process: Reactivity and mechanism.

Recently, clean-up of resistant organic compounds has attracted growing attention. In this study, a novel heterogeneous ultrasound-enhanced sludge biochar catalyst/persulfate (BC/PS/US) process was firstly developed for the degradation of bisphenol A (BPA) in water. The results revealed that BC/PS/US process could successfully achieve a positively synergistic effect between sonochemistry and catalytic chemistry on the degradation of BPA compared to its corresponding comparative process. Nearly 98% of BPA could be degraded within 80 min at optimum reaction conditions. The coexisting substances including Cl-, SO42- and NO3- had no obvious inhibition on the BPA degradation, whereas HCO3- and humic acid (HA) had significant inhibition effects on that. PS decomposition of BC/PS/US process was superior to that of BC/PS or US/PS process. Both SO4- and HO participated in the degradation of BPA, but SO4- was predominant radical in the BC/PS/US process. A possible pathway of BPA degradation was proposed, and the BPA molecule was attacked by SO4- and degraded into five kinds of intermediate products through hydroxylation and demethylation processes. This study helps to comprehend the application of sludge biochar catalyst as a persulfate activator for the degradation of organic compounds under ultrasound irradiation, and provides a new strategy in wastewater treatment.

Photocatalytic removal of phenanthrene and algae by a novel Ca-Ag3PO4 composite under visible light: Reactivity and coexisting effect.

In this study, the feasibility of a novel Ca-Ag3PO4 composite with visible light irradiation for the phenanthrene (PHE) degradation and algae inactivation in artificial seawater was firstly investigated. The experimental findings revealed that Ag3PO4 phase was sucessfully formed on the Ca-based material, and the presence of Ca-based material could effectively keep Ag3PO4 particles stable. An excellent performance on PHE degradation or algae inactivation was observed from Ca-Ag3PO4 composite under visible light irradiation. The degradation of PHE or inactivation of algae not only could be efficiently achieved in the single mode, but also could be successfully achieved in the coexisting mode. Above 96% of PHE and algae were simultaneously removed within 12 h in the Ca-Ag3PO4/visible light system. It was further observed that the degradation of PHE and/or inactivation of algae increased with the increase of Ca-Ag3PO4 dosage. HO was the primary radical responsible for PHE degradation, whereas HO and Ag+ released from Ca-Ag3PO4 mainly contributed to the algae inactivation. A possible mechanism involving the catalytic removal of PHE and algae by Ca-Ag3PO4 under visible light irradiation was proposed. This study provides helpful guide for the simultaneous removal of various pollutants in real seawater.

Insights on the nitrate reduction and norfloxacin oxidation over a novel nanoscale zero valent iron particle: Reactivity, products, and mechanism.

Herein, the application of a novel acid mine drainage-based nanoscale zero valent iron (AMD-based nZVI) for the remediation of nitrate and norfloxacin (NOR) was studied. Experimental results indicated that the catalytic reactivity of AMD-based nZVI toward nitrate reduction was superior to that of iron salt-based nanoscale zero valent iron (Iron salt-based nZVI). The presence of ultrasound irradiation could significantly enhance the reactivity toward both the nitrate reduction and NOR oxidation processes. The optimal efficiencies of nitrate and NOR by AMD-based nZVI/US process could be kept 96 and 94% within 120 min, respectively. Ammonia was identified as a major product in nitrate reduction process, while three oxidation products were observed in NOR degradation process. Both reduction reaction of nitrate from AMD-based nZVI and oxidation reaction of NOR from US-assisted Fenton system might be involved in AMD-based nZVI/US process. The AMD-based nZVI/US process showed a better performance on the removal of NOR compared with that of nitrate. The findings of the present work could be as a guide and show that AMD-based nZVI/US process is feasible for the remediation of both nitrate and NOR in real wastewater.

Downregulation of microRNA-592 protects mice from hypoplastic heart and congenital heart disease by inhibition of the Notch signaling pathway through upregulating KCTD10.

Evidence has demonstrated that the microRNA (miR) may play a significant role in the development of congenital heart disease (CHD). Here, we explore the mechanism of microRNA-592 (miR-592) in heart development and CHD with the involvement of KCTD10 and Notch signaling pathway in a CHD mouse model. Cardiac tissues were extracted from CHD and normal mice. Immunohistochemistry staining was performed to detect positive expression rate of KCTD10. A series of inhibitor, activators, and siRNAs was introduced to verified regulatory functions for miR-592 governing KCTD10 in CHD. Furthermore, the effect of miR-592 on cell proliferation and apoptosis was also investigated. Downregulated positive rate of KCTD10 was observed in CHD mice. Downregulation of miR-592 would upregulate expression of KCTD10 and inhibit the activation of Notch signaling pathway, thus promote cell proliferation. This study demonstrates that downregulation of miR-592 prevents CHD and hypoplastic heart by inhibition of the Notch signaling pathway via negatively binding to KCTD10.

Insights into the simultaneous removal of Cr6+ and Pb2+ by a novel sewage sludge-derived biochar immobilized nanoscale zero valent iron: Coexistence effect and mechanism.

Cr6+ and Pb2+ are both highly toxic pollutants and commonly co-exist in some industrial effluents and contaminated waters. In this study, simultaneous removal of Cr6+ and Pb2+ by a novel sewage sludge-derived biochar immobilized nanoscale zero-valent iron (SSB-nZVI) was systematically investigated. It was well demonstrated that a porous structure was successfully formed on the SSB-nZVI when the starch was used as an additive. A synergistic effect on the adsorption and reduction over the SSB-nZVI was achieved, resulting in nearly 90 and 82% of Cr6+ and Pb2+ removal within 30 min, respectively. Cr6+ was reduced prior to Pb2+. A low pH could accelerate the corrosion of nZVI as well as phosphate leaching. When Malachite green was added as a coexisting organic pollutant, its effective removal was found due to the formation of a Fenton-like system. The SSB-nZVI could be run consecutively three times with a relatively satisfactory performance. Most of Cr6+ was converted into Cr2O3 and Cr(OH)3 on the SSB-nZVI surface, whereas most of Pb2+ species existed as Pb(OH)2 (or PbO). A possible reaction mechanism on the SSB-nZVI involved the adsorption, reduction and precipitation of both Cr6+ and Pb2+ over the particles. Present study sheds light on the insight of the fate and transport of Cr6+ and Pb2+ in aquatic environment, as well provides helpful guide for the remediation of coexistence of pollutants in real applications.

Energy transport pathway in proteins: Insights from non-equilibrium molecular dynamics with elastic network model.

Intra-molecular energy transport between distant functional sites plays important roles in allosterically regulating the biochemical activity of proteins. How to identify the specific intra-molecular signaling pathway from protein tertiary structure remains a challenging problem. In the present work, a non-equilibrium dynamics method based on the elastic network model (ENM) was proposed to simulate the energy propagation process and identify the specific signaling pathways within proteins. In this method, a given residue was perturbed and the propagation of energy was simulated by non-equilibrium dynamics in the normal modes space of ENM. After that, the simulation results were transformed from the normal modes space to the Cartesian coordinate space to identify the intra-protein energy transduction pathways. The proposed method was applied to myosin and the third PDZ domain (PDZ3) of PSD-95 as case studies. For myosin, two signaling pathways were identified, which mediate the energy transductions form the nucleotide binding site to the 50 kDa cleft and the converter subdomain, respectively. For PDZ3, one specific signaling pathway was identified, through which the intra-protein energy was transduced from ligand binding site to the distant opposite side of the protein. It is also found that comparing with the commonly used cross-correlation analysis method, the proposed method can identify the anisotropic energy transduction pathways more effectively.

Simultaneous removal of Cu2+ and bisphenol A by a novel biochar-supported zero valent iron from aqueous solution: Synthesis, reactivity and mechanism.

In this study, a novel biochar-supported zero valent iron (BC-nZVI) was synthesized through a green method. A high performance on the simultaneous removal of Cu2+ and bisphenol A (BPA) by a combination of BC-nZVI with persulfate (BC-nZVI/PS) system was successfully achieved. The simultaneous efficiencies of Cu2+ and BPA could reach 96 and 98% within 60 min, respectively. Both HO• and SO4•- were two major reactive species in BC-nZVI/PS system, and SO4•- was primary radical responsible for the degradation of BPA. Four kinds of Cu species, such as Cu(OH)2, CuO, Cu2O and Cu0 were generated via the adsorption and reduction of the BC-nZVI, whereas six kinds of products of BPA including p-isopropenyl phenol and 4-isopropylphenol were generated via the combined oxidation of SO4•- and HO•. The possible reaction mechanism for the simultaneous removal of Cu2+ and BPA by BC-nZVI/PS system contained a synergistic effect between the reduction of Cu2+ and the oxidation of BPA. This is the first report on the feasibility of the remediation of coexistence of heavy metal and organic compound in aquatic environment using the BC-nZVI/PS system.

[Effects of caspase inhibitor z-VAD-fmk on the expressions of calumenin, caspase-3, GRP78 and GRP94 in adriamycin-injured cardiomyocytes].

OBJECTIVE: To study the effects of Caspase broad spectrum inhibitor Z-VAD-FMK on the expressions of calumenin,caspase-3, GRP78 and GRP94 in adriamycin-injured cardiomyocytes and to discuss whether there is a regulation relationship between calumenin and endo-plasmic reticulum stress and myocardial apoptosis. METHODS: The primary cultured suckling mouse myocardium were randomly divided into control group (cardiomyocyte), adriamycin group (3 mg/L adriamycin + cardiomyocyte) and z-VAD-fm group (3 mg/L adriamycin + 0.1 µmol/L Z-VAD-fmk + cardiomyocyte), each group of cardiomyocytes were cultured in CO2 incubator at 37℃ for 24 h (n=3). The expres-sion ofα -SMA protein in ventricular myocytes was detected by immunohistochemical method. The expressions of calumenin, GRP78, GRP94 and Caspase-3 in the myocardial cells were detected by Western blot. RESULTS: Compared with the control group, the expression of calumenin in adriamycin induced myocardial cells was significantly decreased (P < 0.01), while the expressions of GRP78, GRP94 and Caspase-3 ex-pression were increased (P < 0.01). Compared with adriamycin group, the expression of calumenin in z-VAD-fm group was increased (P < 0.01), while the expressions of GRP78, GRP94 and caspase-3 were decreased (P < 0.01). CONCLUSIONS: The caspase inhibitor z-VAD-fmk inhibited the expression of caspase and increased the expression of calumenin in adriamycin induced myocardial cells, and thus alleviated the endoplasmic reticulum stress.

[Technique of intracorporeal gastrointestinal anastomosis after total laparoscopic gastrectomy].

Malignant or benign diseases of stomach are very common in China. The application of laparoscopy surgery in gastric diseases is a remarkable symbol of current gastric surgery. Laparoscopic assisted radical gastrectomy has gained widespread acceptance for the treatment of gastric cancer. Total laparoscopic radical gastrectomy, which means the gastric resection, lymph nodes dissection and gastrointestinal anastomosis are entirely performed in intracorporeally, is the inheritance and progression of laparoscopic assisted radical gastrectomy. However, controversy still exists regarding the risk and difficulty of intracorporeal anastomosis. In Asian countries including China, total laparoscopic radical gastrectomy has not been extensively performed yet. This review focuses on the issues related to intracorporeal gastrointestinal reconstruction in laparoscopic procedure, such as its history and current status, as well as the surgical technique and risk.

[Intracorporeal hand-sewn technique used in totally laparoscopic colectomy].

OBJECTIVE: To evaluate the safety and feasibility of hand-sewn anastomosis in totally laparoscopic colectomy. METHODS: Clinical data of 19 consecutive patients with benign(n=5) or malignant colonic diseases(n=14, 4 ascending colon cancers, 2 transverse colon cancers, and 8 sigmoid colon cancers) treated with totally laparoscopic colectomy with a hand-sewn anastomosis were reviewed. All the procedures were performed by the same surgeon team including totally laparoscopic resection and hand-sewn anastomosis, ileocolic anastomosis after right hemicolectomy, and hand-sewn purse-string sutures in the colon. RESULTS: Hand-sewn anastomosis was performed for 11 patients and circular-stapled anastomosis with hand-sewn purse-string sutures was performed for other 8 patients. The mean hand-sewn anastomosis time was (49.5 ± 29.4) min, and the mean hand-sewn purse-string sutures time was (13.3 ± 5.5) min. No patients required conversion to laparoscopy-assisted or open surgery, and there were no postoperative complications related to anastomosis. One patient with transverse colon lipoma developed mild intra-abdominal infection after surgery and recovered after conservative treatment. CONCLUSION: Totally laparoscopic intracorporeal hand-sewn anastomosis or hand-sewn purse-string sutures for colectomy is feasible and safe when performed by experienced laparoscopic surgeons.

[Totally laparoscopic Billroth II( gastrectomy without intracorporeal hand-sewn sutures].

OBJECTIVE: To evaluate the safety and feasibility of a novel totally laparoscopic Billroth II gastrectomy. METHODS: Twelve gastric cancer patients underwent totally laparoscopic D2 dissection without intracorporeal hand-sewn sutures in the Xijing Hospital of Fourth Military Medical University between May 2011 and July 2011. In this technique, circular stapling device was used for gastrojejunostomy, and an Endo GIA was used to close the incision at the greater curvature of the stomach. After the completion of the anastomosis, a side-to-side anastomosis (jejunum-afferent loop or jejunum-efferent loop) was performed using an Endo-GIA. RESULTS: No patients required conversion to laparoscopy-assisted or open surgery. The operative time was 196.0±19.3 min, and the blood loss was 169.5±28.8 ml. The number of lymph node harvested was 25.1±3.3. The proximal resection margin and distal resection margin were 8.8±2.4 cm and 6.9±5.5 cm, respectively. The mean time to the first postoperative flatus was 3.1±1.3 days. The length of hospital stay was 4.5±1.9 days. CONCLUSION: This technique is simple and quick. There is no need for laparoscopic hand-sewn suturing. It is safe to perform for totally laparoscopic gastrectomy and reconstruction.

In silico analysis and verification of S100 gene expression in gastric cancer.

BACKGROUND: The S100 protein family comprises 22 members whose protein sequences encompass at least one EF-hand Ca2+ binding motif. They were involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. However, the expression status of S100 family members in gastric cancer was not known yet. METHODS: Combined with analysis of series analysis of gene expression, virtual Northern blot and microarray data, the expression levels of S100 family members in normal and malignant stomach tissues were systematically investigated. The expression of S100A3 was further evaluated by quantitative RT-PCR. RESULTS: At least 5 S100 genes were found to be upregulated in gastric cancer by in silico analysis. Among them, four genes, including S100A2, S100A4, S100A7 and S100A10, were reported to overexpressed in gastric cancer previously. The expression of S100A3 in eighty patients of gastric cancer was further examined. The results showed that the mean expression levels of S100A3 in gastric cancer tissues were 2.5 times as high as in adjacent non-tumorous tissues. S100A3 expression was correlated with tumor differentiation and TNM (Tumor-Node-Metastasis) stage of gastric cancer, which was relatively highly expressed in poorly differentiated and advanced gastric cancer tissues (P < 0.05). CONCLUSION: To our knowledge this is the first report of systematic evaluation of S100 gene expressions in gastric cancers by multiple in silico analysis. The results indicated that overexpression of S100 gene family members were characteristics of gastric cancers and S100A3 might play important roles in differentiation and progression of gastric cancer.

[Laparoscopy-assisted D2 total gastrectomy in advanced gastric cancer].

OBJECTIVE: To investigate the efficacy and advantages of laparoscopy-assisted total gastrectomy (LATG) with D2 dissection of lymph nodes versus conventional open D2 total gastrectomy (OTG) in advanced gastric cancer. METHODS: One hundred and twenty-five patients with advanced gastric cancer in the middle or upper third of the stomach were operated on from July 2005 to March 2007. Of the patients, 59 cases received LATG and 66 OTG with D2 lymph nodes dissection. Clinical data were recorded and compared between the two groups. RESULTS: No patient in the LATG group converted to conventional operation with laparotomy. No operation mortality and no severe morbidity occurred in LATG group. As compared with OTG group, in LATG group operation time was longer [(330 +/- 71) min vs. (261 +/- 54) min, P =0.005] in LATG group, but with similar number of lymph node retrieval (36 +/- 13 vs. 34 +/- 16, P =0.450), less operation blood loss [(175 +/- 101) ml vs. (359 +/- 210) ml, P =0.003], earlier recovery of bowel activity (P = 0.015), and a shorter duration of fever after operation (P = 0.024). CONCLUSIONS: LATG with D2 lymph node dissection in advanced gastric cancer is safe and technically feasible with better operative access and visual field, less operation blood loss and earlier recovery.

[Construction of rat bowel transforming growth factor beta1 recombinant adenovirus vector].

OBJECTIVE: To construct a recombinant adenovirus vector which regulates the expression of rat transforming growth factor beta (TGF-beta1). METHODS: Total RNA was extracted from F344/N rat small intestine pre-treated with Con A to clone TGF-beta1. pTRE-shuttle vector was used as mediator to ligate TGF-beta1 gene and backbone of replication-incompetent adenoviral vector. The constructed recombinant adenovirus contained tetracycline-responsive element which could regulate the expression of inserted genes. After identification, the desired recombinant adenovirus was packaged in HEK 293 cells. Supernatant of high titer adenovirus was collected to detect the TGF-beta1 gene expression by green fluorescent protein(GFP). RESULTS: The constructed recombinant adenovirus was identified by restriction endonucleases cutting, sequencing, PCR and GFP examination. CONCLUSION: Rat TGF-beta1 recombinant adenovirus is established successfully, which provides material and evidence for further research of dendritic cell (DC) modified by TGF-beta1 to induce immune tolerance in rat heterotopic small bowel transplantation.

[Management of chylous leakage after radical operation of gastric cancer].

OBJECTIVE: To investigate the management of chylous leakage after radical operation of gastric carcinoma. METHODS: 161 patients with gastric carcinoma underwent D2-D4 dissection. A double catheterization cannula was employed in each patient around the abdominal aorta above the celiac trunk and crus of diaphragm. Postoperatively, the chylous fluid from the drainage tube was observed, smeared and cultured; infection of chylous fluid was treated. The development of chylous leakage was observed and the optimal time to remove the drainage tube was determined. RESULTS: Chylous leakage occurred in 19 patients. The volume of chylous leakage was less than 250 ml/24 h in 8 patients, 250 - 500 ml/24 h in 7, and 500 - 1500 ml/24 h in 4. Candida albicans was founded in the fluid of chylous leakage in 8 patients, and bacterial infection was found simultaneously in 5 of them. The patients with chylous leakage were healed within 10 - 90 postoperative days. The drainage tube was removed when there was no fluid in the tube and no hydrops in peritoneal cavity by B ultrasound, and the patient were in good condition without signs and symptoms of infections. CONCLUSION: Chylous leakage after D2 - D4 dissection for gastric carcinoma can be cured by immediate diagnosis, thorough drainage, and anti-infectious treatment with regional and continuative washout when the chylous fluid is infected by Candida or bacteria.

[Isolation of a down-regulated novel gene with lower abundance in gastric cancer].

OBJECTIVE: To clone novel gene from suppression subtraction library established for screening down-regulated genes in gastric carcinoma, and the effects of novel gene on gastric tumorigenicity were analyzed. METHODS: Sequencing results of 860 positive colonies chosen randomly were compared by Blast program in GenBank. Novel gene fragment was amplified by rapid amplification of cDNA ends (RACE). The mRNA expression of novel gene was detected by Northern blot and semi-quantitative PCR in 25 cases of gastric carcinoma tissue and counterpart normal gastric mucosa. The structure and chromosomal location of novel gene were investigated by Bio-message technique. RESULTS: A 233 bp novel gene fragment was screened out from 860 clones and a 802 bp novel gene was obtained by RACE. The novel gene was named as GDDM, registered in the number of AF494508 by GenBank. The mRNA expression of GDDM in gastric carcinoma tissue (4.496+/-0.637) was significantly lower than that in the counterpart normal gastric mucosa (36.919+/-6.290)(P<0.01). Chromosomal location of GDDM gene was at 4q31. CONCLUSION: The cloned novel gene, GDDM, is down-regulated in gastric carcinoma, and it is likely to be involved in gastric tumorigenicity.

[The significance of liver hanging maneuver in liver-splitting anterior approach for hepatectomy].

OBJECTIVE: To analyze the feasibility of developing a tunnel between inferior vena cava (IVC) and caudate lobe before passing a tape through it, and to explore the significance of liver hanging maneuver in liver-splitting anterior approach for hepatectomy. METHODS: Blunt dissection was used to develop the tunnel before a tape was passed through. A hemostatic plate was placed on the surface of liver parenchyma if needed. In the procedure of hepatectomy, the tape was pulled up to create an interspace between liver parenchyma and IVC so that the IVC can be protected during transection. RESULTS: Liver hanging maneuver was performed successfully in 47 cases. There were no severe complications related to the procedure in these cases. The procedure was terminated in 1 case because of severe bleeding. CONCLUSIONS: 1. Liver hanging maneuver is feasible in terms of anatomy and technique. 2. With liver hanging maneuver, IVC can be protected safely and the intrahepatic vessels and ductal system at the transaction line can be exposed clearly. It also makes anterior approach for hepatectomy safer and easier.