Isolation and Characterization of a Novel Heterotrophic Nitrifying and Aerobic Denitrifying Bacterium Pseudomonas stutzeri KTB for Bioremediation of Wastewater

Mao-hong Zhou,Hai-ren Ye,Xiao-wei Zhao 한국생물공학회 2014 Biotechnology and Bioprocess Engineering Vol.19 No.2

A novel heterotrophic nitrifying and aerobicdenitrifying bacterium, KTB, was isolated from activatedsludge flocci collected from a biological aerated filteraccording to the modified Takaya method and identified asPseudomonas stutzeri by 16S rDNA gene sequence analysis. When shaking-cultured in the presence of 4.331 mmol/L ofnitrate, 4.511 mmol/L of nitrite and 4.438 mmol/L ofammonium, the strain grew fast, with μmax being 0.42, 0.45,and 0.56/h, and displayed high nitrogen removal efficiency,with nitrogen removal rate being 0.239, 0.362, and 0.361mmol/L/h and nitrogen removal ratio being 99.1, 100.0,and 100.0% in 18 h, respectively. The removal mainlyoccurred in the logarithmic phase. Nitrite accumulation didnot affect denitrification performance. Nitrate concentrationwas below the detectable limit during the whole growthcycle when ammonium was used as sole nitrogen source. It tolerated high DO level and exhibited excellent aggregationability. A possible pathway involved in the nitrogenremoval process, which demonstrated a full nitrificationand denitrification route, was speculated. The strain mightbe a great candidate for biological removal of nitrogencompounds from wastewater.

A κ-Carrageenase from a Newly Isolated Pseudoalteromonas-like Bacterium, WZUC10

Mao-hong Zhou,Jian-she Ma,Jun Li,Hai-ren Ye,Ke-xin Huang,Xiao-wei Zhao 한국생물공학회 2008 Biotechnology and Bioprocess Engineering Vol.13 No.5

A bacterial strain able to produce k-carrageenase, designated WZUC10, was isolated from a live specimen of the red alga Plocamium telfairiae collected in the East China Sea. The phylogenetic evidence and phenotypic features indicate that this strain belongs to the genus Pseudoalteromonas. WZUC10 requires NaCl for growth and k-carrageenan to induce k-carrageenase synthesis; galactose and lactose do not induce it. The optimal growth temperature is 23~27°C. The secreted enzyme, which has a molecular mass of 45 kDa, breaks down k-carrageenan into k-neocarratetraose sulfate and larger oli-gosaccharides with a repeating β-D-Galp4S-(1→4)-α-D-AnGalp structure, but cannot degrade k-neocarratetraose sulfate or k-neocarrahexaose sulfate into k-neocarrabiose sulfate. The enzyme retains 90% of its activity after 2 h at 40°C and is com-pletely inactivated after 7.5 min at 70°C. The enzyme’s optimal temperature is 30°C and its optimal pH is 7.5. The enzyme-catalyzed reaction follows Michaelis-Menten kinetics, with the Michaelis constant (Km) and the turnover number (k) being 0.015 mM and 125 s-¹, respectively. WZUC10 produces 50 U/mL k-carrageenase after cultivation at 25°C for 35 h on a me-dium containing 80 g/L glucose, 5 g/L corn steep liquor, 3 g/L k-carrageenan, and 15 g/L NaCl. k-Neocarratetraose sulfate was prepared simply with precipitation by ethanol:water (5:1, v/v).

Quantitative Detection of Corroded Reinforced Concrete of Different Sizes Based on SMFL

Mao Yang,Jianting Zhou,Qingyuan Zhao,Qianwen Xia,Hong Zhang,Lifeng Wang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.1

In order to solve the problem of quantitative detection of corroded reinforced concrete of different sizes, the quantitative detection experiment based on spontaneous magnetic flux leakage (SMFL) was carried out in batches. Electrochemical corrosion of 27 reinforced concrete specimens was carried out, and the SMFL signals of reinforcement were obtained by magnetic detection equipment. Four-dimensional magnetic indicators M1-M4 that can characterize the corrosion degree of the specimens were defined. The influence of different sizes on the magnetic indicators were analyzed. It is concluded that the thicknesses of the concrete covers affect the magnetic indicators by affecting the lift-off heights z. The influence of diameter of the rebars on the quantitative detection can be eliminated by describing the corrosion degree with the average cross-section loss rate α. The influence of length of the rebars on quantitative detection is not clear yet. Finally, Support Vector Machine (SVM) was introduced to establish a classification model of corrosion classes and magnetic indicators. Using the model to predict the corrosion classes of the specimens can achieve a high classification accuracy. The research provides a new method for the quantitative detection of steel corrosion.

Seismic Bearing Capacity of Shallow Foundations Resting on Rock Masses Subjected to Seismic Loads

Xiao-Ping Zhou,Xin-Bao Gu,Mao-Hong Yu,Qi-Hu Qian 대한토목학회 2016 KSCE JOURNAL OF CIVIL ENGINEERING Vol.20 No.1

This paper analyzes the bearing capacity of shallow foundations resting on rock masses subjected to seismic loads based on limit analysis theory. The non-linear twin shear strength criterion is used to consider the effects of intermediate principal stress on the bearing capacity of shallow foundations. The pseudo-dynamic approach is applied to account for the effects of seismic loads on the bearing capacity of shallow foundations. Both the horizontal and vertical seismic acceleration coefficients and the effects of an amplification factor on the upper bound evaluations of the foundation’s bearing capacity are investigated. The Π-functions are then applied to derive the upper bound solution of the load-bearing capacity. A numerical computation is performed and indicates that the seismic acceleration coefficients, amplification factor and the intermediate principal stress parameter significantly affect the bearing capacity of shallow foundations.

Wnt pathway is involved in 5-FU drug resistance of colorectal cancer cells

Lingfeng He,Hong Zhu,Shiying Zhou,Ting Wu,Huan Wu,Huan Yang,Huiwen Mao,Chandra SekharKathera,Avilala Janardhan,Ashlin M. Edick,Anna Zhang,Zhigang Hu,Feiyan Pan,Zhigang Guo 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

Colorectal cancer (CRC) is one of the leading causes of cancer-related death worldwide. 5-Fluorouracil (5-FU) is widely used in the treatment of cancers, but its antineoplastic activity is limited in drug-resistant cancer cells. To investigate the detailed mechanism of 5-FU resistance, we developed a model of 5-FU-resistant cells from HCT-8 cells, a wellestablished colorectal cancer cell line. We found that the drug-resistant cells demonstrated high expression of TCF4 and β-catenin, indicating an upregulated Wnt pathway. A microarray analysis revealed that the suppression of the checkpoint kinase 1 (CHK1) pathway explained the resistance to 5-FU, especially in p53 wild-type cancer cells such as HCT-8. Our data also demonstrated that the CHK1 pathway is suppressed by the Wnt pathway in 5-FU-resistant cells. In summary, we have discovered a novel mechanism for 5-FU resistance mediated by histone deacetylation, which also revealed the crosstalk between the Wnt pathway and CHK1 pathway.

XRCC1 Arg399Gln Gene Polymorphism and Hepatocellular Carcinoma Risk in the Chinese Han Population: A Meta-analysis

Duan, Wei-Hong,Zhu, Zhen-Yu,Liu, Jun-Gui,Dong, Mao-Sheng,Chen, Jun-Zhou,Liu, Quan-Dda,Xie, Yu,Sun, Ti-Ye,Gao, Ze-Feng,Zhou, Ning-Xin Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Purpose: Numerous studies have evaluated the association between XRCC1 Arg399Gln gene polymorphism and hepatocellular carcinoma risk in the Chinese Han population. However, the results have been inconsistent. We therefore here examined whether the XRCC1 Arg399Gln gene polymorphism confers hepatocellular carcinoma risk by conducting a meta-analysis. Methods: PubMed, Google scholar and China National Knowledge Infrastructure databases were searched for eligible articles in English and Chinese that were published before April 2012. Results: 6 studies involving 1,246 patients with hepatocellular carcinoma and 1,953 controls were included. The association between XRCC1 Arg399Gln gene polymorphism and hepatocellular carcinoma in the Chinese Han population was significant under GG vs AA (OR = 1.48, 95% CI = 1.13 to 1.94). Limiting the analysis to the studies with controls in the Hardy-Weinberg equilibrium, the results were persistent and robust. Conclusions: In the Chinese Han population, the XRCC1 Arg399Gln gene polymorphism is associated with an increased hepatocellular carcinoma risk.

Studies on Decolorization Process for rhEGF as Cosmetic Ingredient

Zhao Xiao-wei,Xu Zhi-nan,Zhou Mao-hong,Cen Pei-lin The Korean Society for Biotechnology and Bioengine 2005 Biotechnology and Bioprocess Engineering Vol.10 No.3

A decolorization process using ion exchange chromatography was developed to refine rhEGF as a cosmetic ingredient. A macroreticular resin (D314) was selected, with respect to its high decolorization rate and recovery yield of rhEGF, and the operational conditions of the decolorization process optimized. The optimum conditions were as follows: the rhEGF effluent was ion exchanged at a flow rate of 60.0mL/h, with an effluent pH 5.0, using a chromatographic column (i.d. 16mm) packed with D314, with a 7.5cm in bed height. The decolorization process was carried out under the optimum conditions, and halted when the effluent volume reached 350mL, giving a decolorization rate and recovery yield of rhEGF higher than 67 and $80\%$, respectively. When the decolorization rate exceeded $67\%$, the final product turned out to be white or light yellowish, which was to the satisfaction of the cosmetic standard.

Studies on Decolorization Process for rhEGF as Cosmetic Ingredient

Zhi-nan Xu,Xiao-wei Zhao,Mao-hong Zhou,Pei-lin Cen 한국생물공학회 2005 Biotechnology and Bioprocess Engineering Vol.10 No.3

A decolorization process using ion exchange chromatography was developed to refine rhEGF as a cosmetic ingredient. A macroreticular resin (D314) was selected, with respect to its high decolorization rate and recovery yield of rhEGF, and the operational conditions of the decolorization process optimized. The optimum conditions were as follows: the rhEGF effluent was ion exchanged at a flow rate of 60.0 mL/h, with an effluent pH 5.0, using a chromatographic column (i.d. 16 mm) packed with D314, with a 7.5 cm in bed height. The decolorization process was carried out under the optimum conditions, and halted when the effluent volume reached 350 mL, giving a decolorization rate and recovery yield of rhEGF higher than 67 and 80%, respectively. When the decolorization rate exceeded 67%, the final product turned out to be white or light yellowish, which was to the satisfaction of the cosmetic standard.

Tumor-Derived Transforming Growth Factor-β is Critical for Tumor Progression and Evasion from Immune Surveillance

Li, Zheng,Zhang, Li-Juan,Zhang, Hong-Ru,Tian, Gao-Fei,Tian, Jun,Mao, Xiao-Li,Jia, Zheng-Hu,Meng, Zi-Yu,Zhao, Li-Qing,Yin, Zhi-Nan,Wu, Zhen-Zhou Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Tumors have evolved numerous mechanisms by which they can escape from immune surveillance. One of these is to produce immunosuppressive cytokines. Transforming growth factor-${\beta}$(TGF-${\beta}$) is a pleiotropic cytokine with a crucial function in mediating immune suppression, especially in the tumor microenvironment. TGF-${\beta}$ produced by T cells has been demonstrated as an important factor for suppressing antitumor immune responses, but the role of tumor-derived TGF-${\beta}$ in this process is poorly understood. In this study, we demonstrated that knockdown of tumor-derived TGF-${\beta}$ using shRNA resulted in dramatically reduced tumor size, slowing tumor formation, prolonging survival rate of tumor-bearing mice and inhibiting metastasis. We revealed possible underlying mechanisms as reducing the number of myeloid-derived suppressor cells (MDSC) and $CD4^+Foxp3^+$ Treg cells, and consequently enhanced IFN-${\gamma}$ production by CTLs. Knockdown of tumor-derived TGF-${\beta}$ also significantly reduced the conversion of na$\ddot{i}$ve $CD4^+$ T cells into Treg cells in vitro. Finally, we found that knockdown of TGF-${\beta}$ suppressed cell migration, but did not change the proliferation and apoptosis of tumor cells in vitro. In summary, our study provided evidence that tumor-derived TGF-${\beta}$ is a critical factor for tumor progression and evasion of immune surveillance, and blocking tumor-derived TGF-${\beta}$ may serve as a potential therapeutic approach for cancer.

Hydrogeochemical signatures origin of a karst geothermal reservoir–the Sinian Dengying Formation in northern Guizhou, China

Pu Liu,Zhengshan Chen,Ganlu Wang,Tie Mao,Chao Li,Yanan Zhou,Hong Xie,Tong Xiang 한국지질과학협의회 2024 Geosciences Journal Vol.28 No.1

The karst geothermal reservoir, Sinian Dengying Formation was investigated from the hydrogeochemical perspective. Integrated techniques including XRD + SEM, isotopes, saturation index and PHREEQC modeling were applied. With 37.3–72 ?, the targeted waters indicate low-mediate temperature geothermal reservoir. The CO2 concentration in the geothermal waters varies from 1.2 mg/L to 52.42 mg/L, and the log(PCO2) value ranges from −2.53 to −1.29, indicating an open carbonate system. A further D-18O stable isotope analysis addresses the geothermal waters are replenished by meteoric water from +815.52 m to +1427.78 m. Strong water-rock interactions are indicated by apparent 18O shift. The dominating hydrochemical type is SO4·HCO3-Ca·Mg with some Cl-Na. The CO2-TDS-SI-Carbonates comprehensive analysis illustrate the origin of Ca2+, Mg2+, and HCO3−, mainly from dolomite. The correlation of 18O-SO42-SI_Gypsum gives sound evidence for the processes of gypsum dissolution. Three inverse models were established and the results showed, that geothermal waters are controlled by two major factors: 1) the adjacent location to salt basin geological profiles with halite dissolution; and 2) the clay minerals such as Na-montmorillonite causing cation exchanges between Na+ and Ca2+ in the geothermal waters, resulting in excess of Na in relation to Cl concentrations.