Mitogen-Activated Protein Kinase Signal Transduction in Solid Tumors

Lei, Yuan-Yuan,Wang, Wei-Jia,Mei, Jin-Hong,Wang, Chun-Liang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Mitogen-activated protein kinase (MAPK) is an important signaling pathway in living beings in response to extracellular stimuli. There are 5 main subgroups manipulating by a set of sequential actions: ERK(ERK1/ERK2), c-Jun N(JNK/SAPK), p38 MAPK($p38{\alpha}$, $p38{\beta}$, $p38{\gamma}$ and $p38{\delta}$), and ERK3/ERK4/ERK5. When stimulated, factors of upstream or downstream change, and by interacting with each other, these groups have long been recognized to be related to multiple biologic processes such as cell proliferation, differentiation, death, migration, invasion and inflammation. However, once abnormally activated, cancer may occur. Several components of the MAPK network have already been proposed as targets in cancer therapy, such as p38, JNK, ERK, MEK, RAF, RAS, and DUSP1. Among them, alteration of the RAS-RAF-MEK-ERK-MAPK(RAS-MAPK) pathway has frequently been reported in human cancer as a result of abnormal activation of receptor tyrosine kinases or gain-of-function mutations in genes. The reported roles of MAPK signaling in apoptotic cell death are controversial, so that further in-depth investigations are needed to address these controversies. Based on an extensive analysis of published data, the goal of this review is to provide an overview on recent studies about the mechanism of MAP kinases, and how it generates certain tumors, as well as related treatments.

A New Neutral-point Voltage Balance Control Based on Virtual Space Vector Modulation for Three-Level NPC Converter

Yuan Lei,Qing Yi,Jiang Yun-hao,Xu An-fei 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.2

To address the neutral-point voltage imbalance problem of three-level NPC converters, a novel neutral-point voltage balance control algorithm based on virtual space vector is proposed. The method reoptimizes the partitioning and reduces the 6 small sectors in the conventional virtual space vector pulse width modulation algorithm to 5 small sectors, reducing the computational effort. Meanwhile, the regulation factor of neutral-point voltage is introduced, and the influence of virtual vector on the neutral-point voltage is used to fine-tune the size of the regulation factor, and the neutral-point voltage is controlled by a kind of hysteresis loop control for neutral-point voltage balancing. Simulation and experimental results show that the algorithm has a good neutral-point voltage balancing effect.

Fabrication of self-reinforcement of porous mullite ceramic using NH4F as additive from kaolinite

Lei Yuan,Jingkun Yu,Rutao Ye,Shaowei Zhang 한양대학교 세라믹연구소 2013 Journal of Ceramic Processing Research Vol.14 No.4

Self-reinforcement of porous mullite ceramics containing needle-liked whiskers were fabricated from a powder mixture of kaolinite, Al(OH)3 and starch with NH4F as additive. The effects of the sintering temperature and the content of NH4F on porosity, phase composition, strength and microstructure of ceramics were investigated. The formation mechanism of needleliked mullite whiskers by in situ synthesis in ceramic body was discussed. The results indicated that lots of large aspect ratio needle-liked mullite whiskers, especially in the 15% NH4F additive sample, were observed. An interlocking structure was formed by needle-liked mullite whiskers to enhance the mechanical strength of porous mullite ceramic. And as the content of NH4F increasing, the bending strength increased. Comparing to the samples without NH4F additive, porous ceramic fabricated by adding NH4F showed a higher degree of mullitization. The formation mechanism of the needle-liked mullite in the ceramic was attributed to the reaction among NH4F and raw materials.

Effect of solvents on the properties of co-precipitated MgO-ZrO2 nano powders

Lei Yuan,Dong Xiang,Jingkun Yu 한양대학교 세라믹연구소 2013 Journal of Ceramic Processing Research Vol.14 No.4

8 mol% MgO-ZrO2 nano-sized powders have been synthesized through the coprecipitation route using ammonia as precipitant. In order to investigate the agglomeration of the nano powders during synthesis, water, butyl alcohol, and a mixture of butyl alcohol and ethanol were utilized as the solvents to precipitate and wash. The characteristics of the different powders were estimated by FT-IR, TG-DSC, XRD and SEM. It has been demonstrated that uniformly dispersed and soft agglomerates containing MgO-ZrO2 nano-sized powders can be obtained when the butyl alcohol, especially the butyl alcohol and ethanol mixture are used. It has been found that the hydroxyl group on the particle surface is replaced by the alkoxy group to alleviate the hard agglomerate.

Research on Large‑scale Photovoltaic Planning Based on Risk Assessment in Distribution Network

Lei Wang,Minyu Yuan,Fan Zhang,Xuli Wang,Jing Ma,Lei Dai,Xianjun Qi,Rui Bi 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.3

Risks caused by large amounts of distributed photovoltaic (PV) feeding into distribution networks, have an impact on PV planning, which has become a critical consideration for distribution networks’ operation. In this paper, a large-scale PV planning method is proposed which based on risk assessment in distribution networks. Cluster division is used to group large-scale distributed PVs. A risk assessment is performed on the distribution network, considering the correlation between PVs and loads. The efects of load fuctuations, PV quantity, capacity and location on the operational risk of the distribution network are analyzed and discussed. A large-scale PV planning model is established with the goal of maximizing the comprehensive benefts, considering the penalty cost of node voltage over-limit and branch power fow over-limit risk. Finally, the genetic algorithm is used to solve the planning model. The simulation results demonstrate the efectiveness of the proposed method.

Characterization and properties of ZrO2-forsterite composites from zircon and magnesite via reaction sintering

Lei Yuan 한양대학교 세라믹연구소 2017 Journal of Ceramic Processing Research Vol.18 No.5

ZrO2-forsterite composites have been successfully prepared from zircon and magnesite powders utilizing reaction sinteringprocess at temperatures of 1350 oC, 1450 oC and 1550 oC. The weight stoichiometric ratio of calcined magnesite and zircon toform forsterite is 31.6 : 68.4, however, in order to study the effects of calcined magnesite on the sintering behavior andproperties of the composites, excessive amounts of calcined magnesite powder by 10%, 20% and 40% have also been addedin the starting materials respectively. XRD results show that the phase of zirconia in the sintered composites transforms frommonoclinic to cubic with increasing the amounts of calcined magnesite powder. SEM observations reveal that increasingsintering temperature is beneficial to the densification of ZrO2-forsterite composites. And increasing the excessive amount ofcalcined magnesite can result in an improvement of thermal shock resistance ability but the decrease of the cold crushingstrength in the ZrO2-forsterite composites.

Novel and Effective Almagate Enema for Hemorrhagic Chronic Radiation Proctitis and Risk Factors for Fistula Development

Yuan, Zi-Xu,Ma, Teng-Hui,Zhong, Qing-Hua,Wang, Huai-Ming,Yu, Xi-Hu,Qin, Qi-Yuan,Chu, Li-Li,Wang, Lei,Wang, Jian-Ping Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.2

Radiation proctitis is a common complication after radiotherapy for pelvic malignant tumors. This study was conducted to assess the efficacy of novel almagate enemas in hemorrhagic chronic radiation proctitis (CRP) and evaluate risk factors related to rectal deep ulcer or fistula secondary to CRP. All patients underwent a colonoscopy to confirm the diagnosis of CRP and symptoms were graded. Typical endoscopic and pathological images, risk factors, and quality of life were also recorded. A total of 59 patients were enrolled. Gynecological cancers composed 93.1% of the primary malignancies. Complete or obvious reduction of bleeding was observed in 90% (53/59) patients after almagate enema. The mean score of bleeding improved from 2.17 to 0.83 (P<0.001) after the enemas. The mean response time was 12 days. No adverse effects were found. Moreover, long-term successful rate in controlling bleeding was 69% and the quality of life was dramatically improved (P=0.001). The efficacy was equivalent to rectal sucralfate, but the almagate with its antacid properties acted more rapidly than sucralfate. Furthermore, we firstly found that moderate to severe anemia was the risk factor of CRP patients who developed rectal deep ulcer or fistulas (P= 0.015). We also found abnormal hyaline-like thick wall vessels, which revealed endarteritis obliterans and the fibrosis underlying this disease. These findings indicate that almagate enema is a novel effective, rapid and well-tolerated method for hemorrhagic CRP. Moderate to severe anemia is a risk factor for deep ulceration or fistula.

Myeloid-Derived Suppressor Cells Are Associated with Viral Persistence and Downregulation of TCRζ Chain Expression on CD8+ T Cells in Chronic Hepatitis C Patients

Qing-Lei Zeng,Bin Yang,Hong-Qi Sun,Guo-Hua Feng,Lei Jin,Zheng-Sheng Zou,Zheng Zhang,Ji-Yuan Zhang,Fu-Sheng Wang 한국분자세포생물학회 2014 Molecules and cells Vol.37 No.1

Myeloid-derived suppressor cells (MDSCs) play an important role in impairing the function of T cells. We characterized MDSCs in two chronic hepatitis C (CHC) cohorts: a cross-sectional group that included 61 treatment-naive patients with CHC, 14 rapid virologic response (RVR) cases and 22 early virologic response (EVR) cases; and a longitudinal group of 13 cases of RVR and 10 cases of EVR after pegylated-interferon-α/ribavirin treatment for genotype 1b HCV infection. Liver samples from 32 CHC patients and six healthy controls were subjected to immunohistochemical analysis. MDSCs frequency in treatmentnaive CHC was significantly higher than in RVR, EVR, or healthy subjects and was positively correlated with HCV RNA. Patients infected with HCV genotype 2a had a significantly higher frequency of MDSCs than those infected with genotype 1b. Decreased T cell receptor (TCR) ζ expression on CD8+ T cells was significantly associated with an increased frequency of MDSCs in treatment-naive CHC patients and was restored by L-arginine treatment in vitro. Increased numbers of liver arginase-1+ cells were closely associated with the histological activity index in CHC. The TCR ζ chain was significantly downregulated on hepatic CD8+ T cells in CHC. During antiviral follow up, MDSCs frequency in peripheral blood mononuclear cells was directly correlated with the HCV RNA load in the plasma and inversely correlated with TCR ζ chain expression in CD8+ T cells in both RVR and EVR cases. Notably, the RVR group had a higher frequency of MDSCs at baseline than the EVR group. Collectively, this study provides evidence that MDSCs might be associated with HCV persistence and downregulation of CD8 ζ chain expression.

Detection and Characterization of PCR-SSCP Markers of the Bovine Lactoferrin Gene for Clinical Mastitis

Zhou, Lei,Yang, Yuan-Yuan,Li, Zhong-Hao,Kong, Li-Juan,Xing, Guan-Dong,Di, He-Shuang,Wang, Gen-Lin Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.10

A total of 80 cows, including 40 top mastitis resistant and 40 top mastitis susceptible animals as Group I and Group II, were selected from a population of 520 cows based on clinical mastitis occurrence. PCR-SSCP analysis on four fragments within the 5'region and two fragments of Exons 4,15 of bovine lactoferrin (bLF) revealed that four fragments-P1,P4,E4,E15-had polymorphisms which totally included six base mutations, and only two of them had significant differences in allele frequencies between resistant and susceptible groups, P1 (53.7% vs. 70.0%, p<0.05) and P4 (55.0% vs. 68.8%, p<0.05). Further study on these two promising markers combined with the milk performance traits of cows demonstrated that their selection would result in higher fat percentage (p<0.05), lower Somatic Cell Score (SCS) (p<0.05) and Clinical Mastitis Residuals (CMR) (p<0.01) indicating higher mastitis resistance and lower milk yield (p<0.05). The putative transcription factor binding sites in the 5'region were also studied by using MatInspector 7.2.2 software, and two signal pathways regulating the expression of bLF including the NF-${\kappa}B$ pathway and nuclear hormone receptor pathway were predicted.

Research Paper : Influences of long-term different types of fertilization on weed community biodiversity in rice paddy fields

( Kai Yuan Wan ),( Yong Tao ),( Ru Hai Li ),( Jun Feng Pan ),( Lei Lei Tang ),( Fang Chen ) 한국잡초학회 2012 Weed Biology and Management Vol.12 No.1

In order to provide a scientific basis for developing integrated weed management strategies in rice paddy fields, this study investigated the influences of different types of fertilization on weed biodiversity. The experiment was conducted at Long-term-located Monitoring Station for Soil Fertility, Agricultural Science Academy, of Jiangxi Province, China. Five fertilization treatments were set: no fertilization (NOF), PK, NP, NK, and NPK. The results showed that the influence of different fertilization treatments on weed community traits followed the models PK > NOF > NK > NP > NPK for species richness, PK > NOF > NK > NP > NPK for species diversity, NPK > NP > NK > NOF > PK for community dominance, and PK > NOF > NK > NP > NPK for community evenness. Under NPK (i.e. balanced fertilization), the weed species diversity and richness and weed community evenness were the lowest. The principal component analysis showed that the weed community was divided into three groups: (i) NK and a part of NOF; (ii) NP and NPK; and (iii) PK and NOF. The correlation analysis indicated that the influence of each macro-element on the weed community followed the model N > P > K. The organic content in the paddy soil might have played an equally important role with the amount of available N in determining the weed community`s characteristics. Regarding the way by which N, P, and K influenced the weed community, the amount of available P and K mainly influenced the organic content, while the amount of available N influenced both the organic content and light transmittance within the canopy, thereby enhancing the capacity of rice to compete with weeds.