A Colorimetric and Fluorescent pH Probe for Extremely Acidic Conditions and its Application in pH Test Paper

Qi-Hua You,Jinhai Shen,Ganping Shen,Liyun Peng,Yuanqin Lu,Qi Fu,Yuqing Xu,Lei Zhang 대한화학회 2018 Bulletin of the Korean Chemical Society Vol.39 No.3

Here, we report a highly water-soluble colorimetric and fluorescent pH probe that works in the pH range 0.2–3.0. The probe showed a rapid response, high stability, and excellent reversibility to acidity. Moreover, the fluorescence of probe was not influenced by the existence of high concentration of cations. The pKa of probe was calculated to be 2.25 ± 0.06. Furthermore, the pH test papers coated with the probe exhibited a distinct color change in acidic conditions.

Excess trehalose and glucose affects chitin metabolism in brown planthopper (Nilaparvata lugens)

Qi-Da Shen,Meng-Meng Yang,Guo-Qiang Xie,Hui-JuanWang,Lu Zhang,Ling-Yu Qiu,Shi-GuiWang,Bin Tang 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

Trehalose is a non-reducing disaccharide that is hydrolyzed by trehalase to yield two glucose molecules. Trehalase is the first enzyme involved in the chitin biosynthesis pathway, and it plays a pivotal role in insect growth and molting. In this study, Nilaparvata lugens, an economically important rice pest in Southeast Asia, was injectedwith trehalose or glucose to investigate their effects on chitin metabolism. Excess trehalose and glucose significantly increased the rate of deformity (molting and/or wing deformities) and mortality in N. lugens. Trehalose, glycogen, and glucose contents were also significantly decreased in N. lugens treated with trehalose or glucose. Chitin content and the expression of NlHK, NlUAP, NlG6PI1, NlGFAT, NlGNPNA, NlPGM1, NlPGM2, NlCHS1, NlCHS1a, NlCHS1b, NlCht3, NlCht4, NlCht6, and NlCht7 were significantly decreased, whereas the expression of NlCht2, NlIDGF, and NlENGase was significantly increased in treated insects. Furthermore, a significant increase in the expression of NlTRE1-1, NlTRE2, and NlTPS1 and a decrease, in the expression of NlTPS2 were observed. Results of this study suggested that excess trehalose and glucose could affect chitin metabolism by regulating the expression of pivotal genes to decrease the chitin content, resulting in the inability of N. lugens to complete its molting process.

FORMATION OF II–VI SEMICONDUCTOR NANOCRYSTALS WITH TUNABLE VISIBLE EMISSION IN AQUEOUS SOLUTION PROMOTED BY HYDRAZINE

QI-HUI SHEN,YAN LIU,XI YU,XIAO-YANG LIU,MING-QIANG ZOU,JIN-FENG LI,JIAN-GUANG ZHOU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2012 NANO Vol.7 No.6

II?VI Semiconductor nanocrystals (NCs) with tunable visible emission, such as CdS, CdSe and CdTe, were synthesized in aqueous solution using thiols as capping molecules. Hydrazine was found to promote the growth of NCs through a special mechanism. In only a few hours, the synthesis process was completed at room temperature. Under moderate conditions, the capping molecules not only changed the growth rate of NCs simply by varying the concentration, but also altered the spectral properties of NCs. The capping molecules with amino groups were propitious to the growth of CdS NCs, whereas the kinetic growth of CdS NCs was more a®ected by the surface passivation e±ciency of NCs than by steric hindrance in the system. The fastest growth of the CdS NCs was achieved when glutathione was used as a capping molecule, while the emission of CdS and CdSe NCs were shown to remain steady and tunable using the same capping molecule. The growth rate of 3-mercaptopropionic acid-capped CdS and CdSe NCs slowed down signi¯-cantly, while CdTe NCs were obtained with excellent emission properties when capped with the same molecule. Furthermore, our approach will also be useful for the study of the kinetic growth of NCs in aqueous solution.

A robotic multiple-shape-memory ionic polymer–metal composite (IPMC) actuator: modeling approach

Shen, Qi,Stalbaum, Tyler,Minaian, Nazanin,Oh, Il-Kwon,Kim, Kwang J IOP 2019 Smart materials & structures Vol.28 No.1

<P>The multiple-shape-memory ionic polymer–metal composite (MSM-IPMC) actuator can demonstrate complex 3D deformation. The MSM-IPMC has two distinct characteristics, which are the electromechanical actuation effect and the thermal-mechanical shape memory effect. The bending, twisting, and oscillating motions of the actuator could be controlled simultaneously or separately by means of thermal-mechanical and electromechanical transduction. In this study, a theoretical model for the MSM-IPMC was developed and experimentally investigated. Based on previous studies on the electromechanical actuation effect of ionic polymer–metal composite (IPMC), a comprehensive physics-based model of MSM-IPMC which couples the actuation effect and the multiple shape memory effect was developed. To verify the model, an MSM-IPMC sample was prepared and used in experimental testing. The simulation results were shown to be in good agreement with the experimental results obtained. The multiple shape memory and recovery rate of three different polymers, namely the Nafion, Aquivion and GEFC of different ions, which are the hydrogen, lithium and sodium, were also tested. Based on the results, it is shown that all the polymers demonstrate the multiple shape memory effect with varying amounts of programmable shapes. The ion type was shown to have an influence on the broad glass transition range of the polymers, which in turn dictated the number of possible programmable shapes for each membrane. The current study is beneficial for the better understanding of the multiple shape memory effect of MSM-IPMC.</P>

Theoretical and experimental investigation of the shape memory properties of an ionic polymer–metal composite

Shen, Qi,Palmre, Viljar,Kim, Kwang J,Oh, Il-Kwon Institute of Physics Publishing 2017 Smart materials & structures Vol.26 No.4

<P>An ionic polymer–metal composite (IPMC) is typically based on a Nafion membrane with electrode plating on both sides and has a promising potential for biomimetic robotics, biomedical devices and human affinity applications. In this paper, the shape memory properties of IPMC were theoretically and experimentally studied. We presented the multiple shape memory properties of a Nafion cylinder. A physics based model of the IPMC was proposed. The free energy density theory was utilized to analyze the shape properties of the IPMC. To verify the model, IPMC samples with Nafion as the base membrane were prepared and experiments were conducted. A simulation of the model was performed and the results were compared with the experimental data. It was successfully demonstrated that the theoretical model can well explain the shape memory properties of the IPMC. The results showed that the reheat glass transition temperature of the IPMC is lower than the programming temperature. It was also found that the back-relaxation of the IPMC decreases as the programming temperature increases. The current study may be useful in order to better understand the shape memory effect of IPMC.</P>

Antiproliferative activities of Garcinia bracteata extract and its active ingredient, isobractatin, against human tumor cell lines

Shen, Tao,Li, Wei,Wang, Yan-Yan,Zhong, Qing-Qing,Wang, Shu-Qi,Wang, Xiao-Ning,Ren, Dong-Mei,Lou, Hong-Xiang 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.3

In our cell based screening of antitumor ingredients from plants, the EtOH extract of Garcinia bracteata displayed antiproliferative effect against human lung adenocarcinoma A549 cells, human breast cancer MCF-7 cells, and human prostate cancer PC3 cells. Phytochemical investigation of this active extract produced nine ingredients, and their structures were established by analysis of MS and NMR spectra. Antiproliferative evaluation of isolated ingredients on A549, MCF-7 and PC3 cells indicated that a xanthone named isobractatin (1) exhibited potent antiproliferative activity against the above three human cancer cell lines with $IC_{50}$ values ranging from 2.90 to $4.15{\mu}M$. Treatment of PC3 cells with 1 led to an enhancement of the cell apoptosis, and arrested cell cycle in the G0/G1 phase. The G0/G1 phase cycle-related proteins analysis showed that the expressions of cyclins D1 and E were reduced by 1, whereas the protein level of cyclin dependent kinase (CDK) inhibitor P21 was induced. Additionally, 1 enhanced PC3 cell apoptosis by activations of Bax, caspases 3 and 9, and by inhibition of Bcl-2. Our combined data illustrated that isobractatin (1) was the antiproliferative ingredient of G. bracteata against three human cancer cell lines, which exerted its antiproliferatrive effect via cell cycle arrest and induction of apoptosis.

Significant Differences in the Clinicopathological Characteristics and Survival of Gastric Cancer Patients from Two Cancer Centers in China and Korea

Shen, Zhan Long,Song, Kyo Young,Ye, Ying Jiang,Xie, Qi Wei,Liang, Bin,Jiang, Kewei,Park, Cho Hyun,Wang, Shan The Korean Gastric Cancer Association 2015 Journal of gastric cancer Vol.15 No.1

Purpose: To compare the clinicopathological data and long-term survival of gastric cancer patients in China and Korea. Materials and Methods: Patients who had undergone gastrectomy for gastric cancer between 1998 and 2009 in 2 high-volume institutions in both China (n=1,637) and Korea (n=2,231) were retrospectively evaluated. Clinicopathological variables, overall survival (OS), progression-free survival (PFS), and surgery-related complications were assessed for all patients and compared between the 2 institutions. Results: Chinese patients included in the study were significantly older and had a significantly lower body mass index (BMI) than the Korean patients. Esophagogastric junction tumors were more frequent in Chinese patients. However, the number of patients with stage I gastric cancer, the number of harvested lymph nodes, and the number of total gastrectomies were significantly higher in the Korean population. Korean patients also presented with fewer undifferentiated tumors than Chinese patients. Furthermore, Korean patients had prolonged OS and PFS for stage III cancers only. BMI, tumor-node-metastasis (TNM) stage, tumor invasion, number of positive lymph nodes, and distant metastases were all independent factors affecting OS and PFS. Conclusions: Although China and Korea are neighboring Asian countries, the clinicopathological characteristics of Chinese patients are significantly different from those of Korean patients. Korean gastric cancer patients had longer OS and PFS than Chinese patients. Influencing factors included TNM stage, tumor invasion, and lymph node metastasis.

Joint-transform Correlator Multiple-image Encryption System Based on Quick-response Code Key

Qi Chen,Xueju Shen,Yue Cheng,Fuyu Huang,Chao Lin,HeXiong Liu 한국광학회 2019 Current Optics and Photonics Vol.3 No.4

A method for joint-transform correlator (JTC) multiple-image encryption based on a quick-response (QR) code key is proposed. The QR codes converted from different texts are used as key masks to encrypt and decrypt multiple images. Not only can Chinese text and English text be used as key text, but also symbols can be used. With this method, users have no need to transmit the whole key mask; they only need to transmit the text that is used to generate the key. The correlation coefficient is introduced to evaluate the decryption performance of our proposed cryptosystem, and we explore the sensitivity of the key mask and the capability for multiple-image encryption. Robustness analysis is also conducted in this paper. Computer simulations and experimental results verify the correctness of this method.

Interleukin-18 Synergism with Interleukin-2 in Cytotoxicity and NKG2D Expression of Human Natural Killer Cells

Qi, Yuan-Ying,Lu, Chao,Ju, Ying,Wang, Zi-E,Li, Yuan-Tang,Shen, Ya-Juan,Lu, Zhi-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.18

Natural killer (NK) cells play an important role in anti-tumor immunity. Interleukin (IL)-18 is an immunoregulatory cytokine that induces potent NK cell-dependent anti-tumor responses when administrated with other cytokines. In this study, we explored the effects of combining IL-18 and IL-2 on NK cytotoxicity as well as expression levels of the NK cell receptor NKG2D in vitro. Freshly isolated PBMCs were incubated for 48 h with IL-18 and IL-2, then CD107a expression on $CD3^-CD56^+$ NK cells was determined by three-colour flow cytometry to evaluate the cytotoxicity of NK cells against human erythroleukemia K562 cells and human colon carcinoma HT29 cells. Flow cytometric analysis was also employed to determine NKG2D expression on NK cells. The combined use of IL-18 and IL-2 significantly increased CD107a expression on NK cells compared with using IL-18 or IL-2 alone, suggesting that the combination of these two cytokines exerted synergistic enhancement of NK cytotoxicity. IL-18 also enhanced NKG2D expression on NK cells when administered with IL-2. In addition, blockade of NKG2D signaling with NKG2D-blocking antibody attenuated the up-regulatory effect of combining IL-18 and IL-2 on NK cytolysis. Our data revealed that IL-18 synergized with IL-2 to dramatically enhance the cytolytic activity of human NK cells in a NKG2D-dependent manner. The results appear encouraging for the use of combined IL-18 and IL-2 in tumor immunotherapy.

Efficacy and Toxicity of Anti-VEGF Agents in Patients with Castration-Resistant Prostate Cancer: a Meta-analysis of Prospective Clinical Studies

Qi, Wei-Xiang,Fu, Shen,Zhang, Qing,Guo, Xiao-Mao Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Background: Blocking angiogenesis by targeting vascular endothelial growth factor (VEGF) signaling pathway to inhibit tumor growth has proven to be successful in treating a variety of different metastatic tumor types, including kidney, colon, ovarian, and lung cancers, but its role in castration-resistant prostate cancer (CRPC) is still unknown. We here aimed to determine the efficacy and toxicities of anti-VEGF agents in patients with CRPC. Materials and Methods: The databases of PubMed, Web of Science and abstracts presented at the American Society of Clinical Oncology up to March 31, 2014 were searched for relevant articles. Pooled estimates of the objective response rate (ORR) and prostate-specific antigen (PSA) response rate (decline ${\geq}50%$) were calculated using the Comprehensive Meta-Analysis (version 2.2.064) software. Median weighted progression-free survival (PFS) and overall survival (OS) time for anti-VEGF monotherapy and anti-VEGF-based doublets were compared by two-sided Student's t test. Results: A total of 3,841 patients from 19 prospective studies (4 randomized controlled trials and 15 prospective nonrandomized cohort studies) were included for analysis. The pooled ORR was 12.4% with a higher response rate of 26.4% (95%CI, 13.6-44.9%) for anti-VEGF-based combinations vs. 6.7% (95%CI, 3.5-12.7%) for anti-VEGF alone (p=0.004). Similarly, the pooled PSA response rate was 32.4% with a higher PSA response rate of 52.8% (95%CI: 40.2-65.1%) for anti-VEGF-based combinations vs. 7.3% (95%CI, 3.6-14.2%) for anti-VEGF alone (p<0.001). Median PFS and OS were 6.9 and 22.1 months with weighted median PFS of 5.6 vs. 6.9 months (p<0.001) and weighted median OS of 13.1 vs. 22.1 months (p<0.001) for anti-VEGF monotherapy vs. anti-VEGF-based doublets. Conclusions: With available evidence, this pooled analysis indicates that anti-VEGF monotherapy has a modest effect in patients with CRPC, and clinical benefits gained from anti-VEGF-based doublets appear greater than anti-VEGF monotherapy.