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      • Prognostic Evaluation of Categorical Platelet-based Indices Using Clustering Methods Based on the Monte Carlo Comparison for Hepatocellular Carcinoma

        Guo, Pi,Shen, Shun-Li,Zhang, Qin,Zeng, Fang-Fang,Zhang, Wang-Jian,Hu, Xiao-Min,Zhang, Ding-Mei,Peng, Bao-Gang,Hao, Yuan-Tao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

        Objectives: To evaluate the performance of clustering methods used in the prognostic assessment of categorical clinical data for hepatocellular carcinoma (HCC) patients in China, and establish a predictable prognostic nomogram for clinical decisions. Materials and Methods: A total of 332 newly diagnosed HCC patients treated with hepatic resection during 2006-2009 were enrolled. Patients were regularly followed up at outpatient clinics. Clustering methods including the Average linkage, k-modes, fuzzy k-modes, PAM, CLARA, protocluster, and ROCK were compared by Monte Carlo simulation, and the optimal method was applied to investigate the clustering pattern of the indices including platelet count, platelet/lymphocyte ratio (PLR) and serum aspartate aminotransferase activity/platelet count ratio index (APRI). Then the clustering variable, age group, tumor size, number of tumor and vascular invasion were studied in a multivariable Cox regression model. A prognostic nomogram was constructed for clinical decisions. Results: The ROCK was best in both the overlapping and non-overlapping cases performed to assess the prognostic value of platelet-based indices. Patients with categorical platelet-based indices significantly split across two clusters, and those with high values, had a high risk of HCC recurrence (hazard ratio [HR] 1.42, 95% CI 1.09-1.86; p<0.01). Tumor size, number of tumor and blood vessel invasion were also associated with high risk of HCC recurrence (all p< 0.01). The nomogram well predicted HCC patient survival at 3 and 5 years. Conclusions: A cluster of platelet-based indices combined with other clinical covariates could be used for prognosis evaluation in HCC.

      • A 4th-Order Low-distortion Low-pass ΣΔ Modulator Using Timing-Sharing Technique

        Hong-guo Zhang,Ji-bao Zhang,Ming-yuan Ren 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.9

        A 4th-Order low-distortion low-pass ΣΔ modulator structure is proposed in this paper, which uses the timing-sharing between the 3rd and 4th integrators during one clock phase. Compared with conventional cascade of integrators with distributed feed-forward (CIFF) sigma-delta modulator structure, the proposed structure not only solves the critical timing issue for the quantizer and feedback DAC path, but also eliminates an extra active adder to sum up the input feed-forward. By methods of delay redistribution structure, the time for quantization and feedback dynamic element match (DEM) operation can be extended from a non-overlapping interval for a conventional low-distortion structure to half of the sampling clock period. Capacitive input feed-forward (CIF) methodology eliminates the adder in front of the quantizer. Further, the op-amp of the last integrator is used as an active adder by op-amp sharing. Therefore, the power consumption can be reduced and the linearity of the feedback DAC is improved because of the increasing time which used for implementation of DEM algorism. The proposed 4th-Order low-distortion low-pass ΣΔ modulator with 4-bit quantizer is simulated in MATLAB. From the simulation results, the proposed structure can achieve a peak SNR (signal- to-noise ratio) of 87dB with 2.5MHz bandwidth under 32 oversampling ratio at 160MHz sampling frequency and the ENOB of 14.234bits in non-ideal condition.

      • KCI등재

        Codelivery of hydrophilic and hydrophobic drugs in a microneedle patch for the treatment of skin pigmentation

        Li Qin Zhang,Xiao Peng Zhang,Yu Ying Hao,Bao Li Zhang,Xin Dong Guo 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.88 No.-

        When overexposed to ultraviolet B (UVB) irradiation, skin can cause a series of abnormal reactions, suchas excessive pigmentation and solar elastosis. In order to better treat the skin after overexposed to UVB,we designed a dissolving microneedles (MNs) loading hydrophilic ascorbic acid and hydrophobic vitaminA palmitate to achieve codelivery. Here, we confirmed that MNs had enough mechanical strength toinsert the skin and two drugs were delivered subcutaneously in sequence in vitro. In white guinea pigs,surface observation and histological observation results confirmed that two drugs by MNs transdermaldelivery were better than topical administration in the treatment of UVB-damaged skin. The MNs providea method of loading different drugs into the needles and advance the development of transdermal drugdelivery.

      • Prognostic Significance of Circulating Tumor Cells in Small-Cell Lung Cancer Patients: a Meta-analysis

        Zhang, Jiao,Wang, Hai-Tao,Li, Bao-Guo Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

        Circulating tumor cells (CTCs) are believed to be particularly important and a reliable marker of malignancy. However, the prognostic significance of CTCs detected in patients with small cell lung cancer (SCLC) is still unclear. We therefore aimed to assess the prognostic relevance of CTCs using a meta-analysis. We searched PubMed for relevant studies and statistical analyses were conducted to calculate the hazard ratio (HR) and 95% confidence intervals (CIs) using fixed or random-effect models according to the heterogeneity of included studies. A total of 7 papers covering 440 SCLC patients were combined in the final analysis. The meta-analysis revealed that CTCs were significantly associated with shorter overall survival (HR=1.9; 95%CI: 1.19-3.04; Z=2.67; P<0.0001) and progression-free survival (HR=2.6; 95%CI: 1.9-3.54; Z=6.04; P<0.0001). The results thus suggest that the presence of CTCs indicates a poor prognosis in patients with SCLC. Further well-designed prospective studies are required to explore the clinical applications of CTCs in SCLC.

      • Focus Improvement of High-Squint SAR Based on Azimuth Dependence of Quadratic Range Cell Migration Correction

        Zhang, Shuang-Xi,Xing, Meng-Dao,Xia, Xiang-Gen,Zhang, Lei,Guo, Rui,Bao, Zheng IEEE 2013 IEEE geoscience and remote sensing letters Vol.10 No.1

        <P>In this letter, we discuss the problem that linear range cell walk correction in the azimuth time domain may cause space variation along the azimuth not only to the quadratic phase but also to the quadratic range cell migration (QRCM) under the conditions of high resolution and large scene along the azimuth. Moreover, an algorithm is proposed to deal with this problem. The proposed algorithm adopts the azimuth space variation filtering in the range frequency domain. In addition, the range-dependence component of QRCM is corrected by linear chirp scaling, and the unified QRCM can be corrected in the 2-D frequency domain. The proposed algorithm, without interpolation, can be easily implemented by integrating with motion compensation for image processing. Simulation and airborne strip-map real data show the accuracy and efficiency of the proposed algorithm.</P>

      • KCI등재

        Simulated Ion Velocity Distribution and Its Incoherent Scattering Spectrum in the High-latitude Ionosphere

        Bao-Ke Ma,Li-Xin Guo,Hong-Tao Su,Bei-Chen Zhang 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.8

        If the relatively larger convection electric field and small the collision frequency between ions andneutrals in the high-latitude ionosphere are considered, the integral solution of the non-Maxwellianion velocity distribution function for the relaxation collision model is simplified, and a torus distributionfunction of the ion velocity is obtained. Also, the feature of the torus velocity distributionfunction is analyzed and simulated with different parameters in high-latitude ionosphere. Furthermore,by using the electromagnetic radiation theory of Sheffield and taking into account the iontemperature anisotropy and its variation with the electric field, we simulate the incoherent scatteringspectrum of ions in different directions. The research shows that the ionospheric convectionelectric field, the ion-neutral collision frequency and the ion anisotropic temperature distributionall have an effect on the incoherent scattering spectrum.

      • KCI등재

        Molecular characterization and inhibition analysis of the acetylcholinesterase gene from the silkworm maggot, Exorista sorbillans

        ( Guo Jun Lang ),( Ming Yan Zhang ),( Bao Ling Li ),( Lin Lin Yu ),( Xing Meng Lu ),( Chuan Xi Zhang ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2010 BMB Reports Vol.43 No.8

        Several organophosphorus (OP) insecticides can selectively kill the silkworm maggot, Exorista sorbillans (Es) (Diptera: Tachinidae), while not obviously affecting the host (Bombyx mori) larvae, but the mechanism is not yet clear. In this study, the cDNA encoding an acetylcholinesterase (AChE) from the field Es was isolated. One point mutation (Gly353Ala) was identified. The Es-353G AChE and Es-353A AChE were expressed in baculovirus- insect cell system, respectively. The inhibition results showed that for eserine and Chlorpyrifos, Es-353A AChE was significantly less sensitive than Es-353G AChE. Meanwhile, comparison of the I(50) values of eserine, dichlorvos, Chlorpyrifos and omethoate of recombinant Es AChEs with its host (Bombyx mori) AChEs indicated that, both Es AChEs are more sensitive than B. mori AChEs. The results give an insight of the mechanism that some OP insecticides can selectively kills Es while without distinct effect on its host, B. mori. [BMB reports 2010; 43(8): 573-578]

      • KCI등재후보

        DISPERSION OF CARBON NANOFIBERS IN AQUEOUS SOLUTION

        BAO-MIN WANG,YUAN ZHANG,ZHI-QIANG GUO,YU HAN,HAI-NAN MA 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2012 NANO Vol.7 No.6

        Carbon nano¯bers (CNFs) were puri¯ed by the method of heat treating, and stable homogeneous suspensions of heat-treated CNFs were prepared by using methylcellulose (MC) as a surfactant. The heat-treated CNFs were characterized by di®erential thermal analysis (DTA) and thermogravimetry analysis (TGA), and the sonication-driven dispersion of CNFs in aqueous solution was investigated by measuring ultraviolet absorbency (UV absorbency), zeta potential, adsorption isotherm of MC on CNFs and surface tension of CNF suspensions. In these CNF suspensions, the zeta potentials of CNFs progressively increase with increasing MC concentration, and change from ?15.4?0 mV. The surface tension of CNF suspensions decrease from 38.87mN/m to 36.54mN/m. The adsorption isotherm of MC on CNFs shows an adsorption platform (namely \L" style), and the adsorption isotherm reaches the saturation plateau at MC concentration of about 0.4 g/L. All results show that the optimum concentration ratio of MC to CNFs is 2:1 for dispersion.

      • SCOPUSKCI등재

        Highly Chemo- and Regioselective Reaction of Hydroxybenzenes in Acidic Ionic Liquid

        Guo, Hui,Zhuang, Yu Wei,Cao, Jian,Zhang, Guo Bao Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.9

        Highly chemo- and regioselective reaction of hydroxybenzenes with ${\alpha},{\beta}$-unsaturated compounds in acidic ionic liquid l-butyl-3-methylimidazolium hydrogen sulphate ([BMIM]HSO4) was reported for the first time. A series of oxa-Michael adducts and Friedel-Crafts alkylated products were synthesized with good yields. The acidic ionic liquid could be easily recycled for at least 5 times with only minor loss in activity.

      • Genetic Variations in the HIF1A Gene Modulate Response to Adjuvant Chemotherapy after Surgery in Patients with Colorectal Cancer

        Zhang, Yi,Wang, Peng,Zhou, Xing-Chun,Bao, Guo-Qiang,Lyu, Zhuo-Ming,Liu, Xiao-Nan,Wan, Shao-Gui,He, Xian-Li,Huang, Qi-Chao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

        Background: Hypoxia-inducible factor $1{\alpha}$ (HIF-$1{\alpha}$) plays an important role in regulating cell survival and angiogenesis, which are critical for tumor growth and metastasis. Genetic variations of HIF1A have been shown to influence the susceptibility to many kinds of human tumors. Increased expression of HIF-$1{\alpha}$ has also been demonstrated to be involved in tumor progression. However, the prognostic value of single nucleotide polymorphisms (SNPs) inthe HIF1A gene remains to be determined in most cancer types, including colorectal cancer (CRC). In this study, we sought to investigate the predictive role of HIF1A SNPs in prognosis of CRC patients and efficacy of chemotherapy. Materials and Methods: We genotyped two functional SNPs in HIF1A gene using the Sequenom iPLEX genotyping system and then assessed their associations with clinicopathological parameters and clinical outcomes of 697 CRC patients receiving radical surgery using Cox logistic regression model and Kaplan Meier curves. Results: Generally, no significant association was found between these 2 SNPs and clinical outcomes of CRC. In stratified analysis of subgroup without adjuvant chemotherapy, patients carrying CT/TT genotypes of rs2057482 exhibited a borderline significant association with better overall survival when compared with those carrying CC genotype [Hazard ratio (HR), 0.47; 95% confidence interval (95% CI): 0.29-0.76; P < 0.01]. Moreover, significant protective effects on CRC outcomes conferred by adjuvant chemotherapy were exclusively observed in patients carrying CC genotype of rs2057482 and in those carrying AC/CC genotype of rs2301113. Conclusions: Genetic variations in HIF1A gene may modulate the efficacy of adjuvant chemotherapy after surgery in CRC patients.

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