Five new anthraquinones from the seed of Cassia obtusifolia

Yi-Long Xu,Li-Ying Tang,Xi-Dan Zhou,Guo-Hong Zhou,Zhu-Ju Wang 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.6

A phytochemical investigation on the seeds ofCassia obtusifolia led to the isolation of five new anthraquinones,including one aglycon and four glycosides. Thestructures were elucidated by analysis of extensive spectroscopicdata and the results of acid hydrolysis. All theseisolates were evaluated for their inhibitory effects againsta-glucosidase, and 1 showed potent activity with IC50value of 185 ± 15 lM.

Protocols for Privacy-Preserving DBSCAN Clustering

XU Wei-jiang,HUANG Liu-sheng,LUO Yong-long,YAO Yi-fei,JING Wei-wei 보안공학연구지원센터 2007 International Journal of Security and Its Applicat Vol.1 No.1

Cooperative computation is one of the most important fields in computer science. In recent years, the development of networking increases the desirability of cooperative computation. But privacy concerns often prevent different parties from sharing their data. Secure multiparty computation techniques can dispel parties’ doubts about revealing privacy information in this situation. On the other hand, Data mining has been a popular research area for more than a decade. However, in many applications, the data are originally collected at different sites owned by different users. This paper considers the problem of privacy preserving DBSCAN clustering over vertically partitioned data based on some results of SMC. An efficient secure intersection protocol is first proposed. The security and complexity of the protocols are also analyzed. The results show that the protocols preserve the privacy of the data and the time complexity as well as the communication complexity is acceptable.

Improving the quality of breast ultrasound examination performed by inexperienced ultrasound doctors with synchronous tele-ultrasound: a prospective, parallel controlled trial

Yi-Kang Sun,Xiao-Long Li,Qiao Wang,Bo-Yang Zhou,An-Qi Zhu,Chuan Qin,Le-Hang Guo,Hui-Xiong Xu 대한초음파의학회 2022 ULTRASONOGRAPHY Vol.41 No.2

Purpose: This prospective study explored the value of synchronous tele-ultrasound (US) to aid doctors inexperienced in US with breast US examinations.Methods: In total, 99 patients were enrolled. Two trainee doctors who were inexperienced in US (trainee A [TA] and trainee B [TB]) and one doctor who was an expert in US completed the US examinations sequentially. TA completed the US examinations independently, while TB was instructed by the expert using synchronous tele-US. Subsequently, the expert performed on-site US examinations in person. Separately, they selected the most clinically significant nodule as the target nodule. Consistency with the expert and image quality were compared between TA and TB to evaluate tele-US. Furthermore, TB and the patients evaluated tele-US through questionnaires.Results: TB demonstrated higher consistency with the expert in terms of target nodule selection than TA (93.3% vs. 63.3%, P<0.001). TB achieved good inter-observer agreement (ICC, >0.75) with the expert on five US features (5/9, 55.6%), while TA only did so for one (1/9, 11.1%) (P=0.046). TB’s image quality was higher than TA’s in gray value, time gain compensation, depth, color Doppler adjustment, and the visibility of key information (P=0.018, P<0.001, P<0.001, P=0.033, and P=0.006, respectively). The comprehensive assessment score was higher for TB than for TA (3.96±0.82 vs. 3.09±0.87, P<0.001). Tele-US was helpful in 69.7% of US examinations and had a training effect in 68.0%. Furthermore, 63.6% of patients accepted tele-US and 60.6% were willing to pay.Conclusion: Tele-US can help doctors inexperienced in US to perform breast US examinations.

Clinical Study of Tumor Angiogenesis and Perfusion Imaging Using Multi-slice Spiral Computed Tomography for Breast Cancer

Xu, Na,Lei, Zhen,Li, Xiao-Long,Zhang, Jun,Li, Chen,Feng, Guo-Quan,Li, Di-Nuo,Liu, Jing-Yi,Wei, Qiang,Bian, Ting-Ting,Zou, Tian-Yu Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

Objectives: To explore the correlation between multi-slice spiral CT (MSCT) perfusion parameters and the expression of vascular endothelial growth factor (VEGF) as well as matrix metalloproteinase-2 (MMP-2) in breast cancer. Methods: Forty five breast cancer patients and 16 patients with benign breast tumor, both confirmed by pathology examination, were enrolled. All underwent MSCT perfusion imaging to obtain perfusion maps and data for parameters including blood flow (BF), blood volume (BV) and permeability surface (PS). Cancer patients did not receive treatment prior to surgery. The expression of VEGF and MMP-2 were examined with both immunohistochemistry and Western blotting. Results: The levels of VEGF and MMP-2 by immunohistochemistry were significantly higher in the breast cancer group (P < 0.01) than the benign tumor group. Relative OD values from Western blotting were also higher in cancer cases (P < 0.05). Similarly, the mean MSCT perfusion parameters (BF, BV, PS) were significantly higher in the breast cancer group (P < 0.01), BF and BV positively correlating with VEGF expression (r = 0.878 and 0.809 respectively, P < 0.01); PS and VEGF and MMP-2 expression were also positively correlated (r= 0.860, 0.786 respectively, P < 0.01). Conclusion: There is a correlation between breast cancer MSCT perfusion parameters and VEGF andMMP-2 expression, which might be useful for detection of breast lesions, qualitative diagnosis of breast cancer, and evaluation of breast cancer treatment.

Synchronous tele-ultrasonography is helpful for a naive operator to perform high-quality thyroid ultrasound examinations

Xiao-Long Li,Yi-Kang Sun,Qiao Wang,Zi-Tong Chen,Zhe-Bin Qian,Le-Hang Guo,Hui-Xiong Xu 대한초음파의학회 2022 ULTRASONOGRAPHY Vol.41 No.4

Purpose: This study investigated the value of synchronous tele-ultrasonography (TUS) for naive operators in thyroid ultrasonography (US) examinations.Methods: Ninety-seven patients were included in this prospective, parallel-controlled trial. Thyroid scanning and diagnosis were completed by resident A independently, resident B with guidance from a US expert through synchronous TUS, and an on-site US expert. The on-site expert’s findings constituted the reference standard. Two other off-site US experts analyzed all data in a blind manner. Inter-operator consistency between the two residents and the on-site US expert for thyroid size measurements, nodule measurements, nodule features, American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) categories, and image quality was compared. Two questionnaires were completed to evaluate the clinical benefit.Results: Resident B detected more nodules consistent with the on-site expert than resident A did (89.4% vs. 56.5%, P<0.001). Resident B achieved excellent consistency with the on-site expert in terms of ACR TI-RADS categories, nodule composition, shape, echogenic foci, and vascularity (all intra-class correlation coefficients [ICCs] >0.75), while resident A achieved lower consistency in ACR TI-RADS categories, composition, echogenicity, margin, echogenic foci, and vascularity (all ICCs 0.40-0.75). Residents A and B had excellent consistency in target nodule measurements (all ICCs >0.75). Resident B achieved better performance than resident A for gray values, time gain compensation, depth, color Doppler adjustment, and the visibility of key information (all P<0.05). Furthermore, 61.9% (60/97) of patients accepted synchronous TUS, and 59.8% (58/97) patients were willing to pay for it.Conclusion: Synchronous TUS can help inexperienced residents achieve comparable thyroid diagnostic capability to a US expert.

Design of 39-GHz Up- and Down-Conversion Mixers for 5G mmWave TDD Applications

Wang Yi-Yang,Duan Haipeng,He Long,Wu Xu,Wang Dongming,Li Lianming 한국전자파학회 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.2

This article presents fully integrated 39-GHz bidirectional up- and down-conversion mixers for 5G millimeter-wave (mmWave) applications. Fabricated in a 65-nm CMOS process with a 1.2-V supply voltage, the up- and down-conversion mixers consume 39 and 43 mW, respectively. For 5G time-division duplexing (TDD) operation, intermediate-frequency (IF)/local-oscillator (LO)/radio-frequency (RF) T/R switches are introduced. For better isolation and low insertion loss between the up- and down-conversion mixer, a series-shunt singlepole double-throw (SPDT) structure and an equivalent lumped λ/4 transmission line are proposed for IF and RF T/R switches, respectively. To realize compact area and wide bandwidth, a transformer-based matching network is adopted in this design. Targeting multi-channel phased array applications, the measurement result shows that the up-conversion mixer achieves a 2.5-dB peak conversion gain with 6.5 GHz 3-dB bandwidth. Including the insertion loss of the switch and IF signal routing, at the maximum gain of 36.5 GHz, the up-conversion mixer achieves an output 1-dB gain compression point (OP1dB) of 2.5 dBm. Furthermore, the down-conversion mixer achieves a 5-dB peak conversion gain with a 9.7-GHz 3-dB bandwidth.

RTN4 3'-UTR Insertion/Deletion Polymorphism and Susceptibility to Non-Small Cell Lung Cancer in Chinese Han Population

Lu, De-Yi,Mao, Xu-Hua,Zhou, Ying-Hui,Yan, Xiao-Long,Wang, Wei-Ping,Zheng, Ya-Biao,Xiao, Juan-Juan,Zhang, Ping,Wang, Jian-Guo,Ashwani, Neetika,Ding, Wei-Liang,Jiang, Hua,Shang, Yan,Wang, Ming-Hua Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Nogo protein, encoded by gene reticulon-4 (RTN4), includes three major isoforms by different splicing, named Nogo-A Nogo-B and Nogo-C. Nogo proteins play an important role in the apoptosis of cells, especially in tumor cells. RTN4 single nucleotide polymorphisms (SNPs) can influence the efficiency of transcription and translation thus being related with an individual's predisposition to cancer. The CAA insertion/deletion polymorphism (rs34917480) within RTN4 3'-UTR has been reported to be associated with many cancer types. In order to investigate the relationship between this polymorphism and susceptibility to non-small cell lung cancer (NSCLC) in the Chinese population, we conducted the present case-control study including 411 NSCLC patients and 471 unrelated healthy controls. The genotype distributions were significantly different between cases and controls (p=0.014). We found that the del allele could significantly increase NSCLC risk (ins/ins vs ins/del: p=0.007, OR 1.46, 95%CI=1.11-1.93; dominant model: p=0.004, OR 1.47, 95%CI=1.13-1.92 and allele model: p=0.008, OR 1.35, 95%CI=1.08-1.67). This association was stronger in participants over 60 years old, males and smokers. We therefore conclude that the CAA insertion/deletion polymorphism (rs34917480) contributes to non-small cell lung cancer risk in Chinese population. Age, sex and environmental exposure are also related to carcinogenic effects of rs34917480.

Concurrent Hypermethylation of SFRP2 and DKK2 Activates the Wnt/β-Catenin Pathway and Is Associated with Poor Prognosis in Patients with Gastric Cancer

Wang, Hao,Duan, Xiang-Long,Qi, Xiao-Li,Meng, Lei,Xu, Yi-Song,Wu, Tong,Dai, Peng-Gao Korean Society for Molecular and Cellular Biology 2017 Molecules and cells Vol.40 No.1

Aberrant hypermethylation of Wnt antagonists has been observed in gastric cancer. A number of studies have focused on the hypermethylation of a single Wnt antagonist and its role in regulating the activation of signaling. However, how the Wnt antagonists interacted to regulate the signaling pathway has not been reported. In the present study, we systematically investigated the methylation of some Wnt antagonist genes (SFRP2, SFRP4, SFRP5, DKK1, DKK2, and APC) and their regulatory role in carcinogenesis. We found that aberrant promoter methylation of SFRP2, SFRP4, DKK1, and DKK2 was significantly increased in gastric cancer. Moreover, concurrent hypermethylation of SFRP2 and DKK2 was observed in gastric cancer and this was significantly associated with increased expression of ${\beta}-catenin$, indicating that the joint inactivation of these two genes promoted the activation of the Wnt signaling pathway. Further analysis using a multivariate Cox proportional hazards model showed that DKK2 methylation was an independent prognostic factor for poor overall survival, and the predictive value was markedly enhanced when the combined methylation status of SFRP2 and DKK2 was considered. In addition, the methylation level of SFRP4 and DKK2 was correlated with the patient's age and tumor differentiation, respectively. In conclusion, epigenetic silencing of Wnt antagonists was associated with gastric carcinogenesis, and concurrent hypermethylation of SFRP2 and DKK2 could be a potential marker for a prognosis of poor overall survival.

Effect of Cu doping on the SCR activity of CeO2 catalyst prepared by citric acid method

Rui-Tang Guo,Wen-long Zhen,Wei-Guo Pan,Yue Zhou,Jie-nan Hong,Hong-jian Xu,Qiang Jin,Cheng-gang Ding,Shi-yi Guo 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4

CeO2–CuO catalyst prepared by citric acid method was investigated for selective catalytic reduction of NO with NH3. The activity of the CeO2 catalyst was enhanced about 8–27% in the temperature range of 125–225 ℃ at a space velocity of 28,000 h 1 by the addition of Cu. It was found that the state of Cu species had great impact on the SCR performance of CeO2–CuO catalyst. Cu2+ can enhance the low temperature activity of SCR reaction, while CuO would promote NH3 oxidation before SCR reaction at high temperature, which would cause the decrease of its high temperature SCR activity.

Concurrent Hypermethylation of SFRP2 and DKK2 Activates the Wnt/β-Catenin Pathway and Is Associated with Poor Prognosis in Patients with Gastric Cancer

Hao Wang,Xiang-Long Duan,Xiao-Li Qi,Lei Meng,Yi-Song Xu,Tong Wu,Peng-Gao Dai 한국분자세포생물학회 2017 Molecules and cells Vol.40 No.1

Aberrant hypermethylation of Wnt antagonists has been observed in gastric cancer. A number of studies have focused on the hypermethylation of a single Wnt antagonist and its role in regulating the activation of signaling. However, how the Wnt antagonists interacted to regulate the signaling pathway has not been reported. In the present study, we systematically investigated the methylation of some Wnt antagonist genes (SFRP2, SFRP4, SFRP5, DKK1, DKK2, and APC) and their regulatory role in carcinogenesis. We found that aberrant promoter methylation of SFRP2, SFRP4, DKK1, and DKK2 was significantly increased in gastric cancer. Moreover, concurrent hypermethylation of SFRP2 and DKK2 was observed in gastric cancer and this was significantly associated with increased expression of -catenin, indicating that the joint inactivation of these two genes promoted the activation of the Wnt signaling pathway. Further analysis using a multivariate Cox proportional hazards model showed that DKK2 methylation was an independent prognostic factor for poor overall survival, and the predictive value was markedly enhanced when the combined methylation status of SFRP2 and DKK2 was con-sidered. In addition, the methylation level of SFRP4 and DKK2 was correlated with the patient’s age and tumor differentiation, respectively. In conclusion, epigenetic silencing of Wnt antagonists was associated with gastric carcinogenesis, and concurrent hypermethylation of SFRP2 and DKK2 could be a potential marker for a prognosis of poor overall survival.