Evaluation of the Stability of Aspirin in Solid State by the Programmed Humidifying and Non-isothermal Experiments

Lin-Li Li,Xian-Cheng Zhan,Jian-Lin Tao 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.3

The influence of both moisture and heat on the stability of aspirin was investigated by a single pair of experiments, one with programmed humidity control and the other non-isothermal, rather than many standard isothermal studies, each at constant relative humidity. In experiments, we adopted the acid-base back titration method to measure the content of aspirin in the presence of its degradation products. It was found that the degradation of aspirin could be expressed as ln[(c0-c)/c]=kt+D, where D was a lag time item not related to humidity and temperature. The relationship between the degradation rate constant k and humidity Hr and temperature T could be described as Arrhenius equation multiplied by an exponential item of relative humidity: k = A · exp(mHr) · exp(-(Ea/RT)), where A, Ea and m were the pre-exponential factor, observed activation energy, and a parameter related to humidity, respectively. The results obtained from the programmed humidifying and non-isothermal experiments, A=(1.09±2.04)×1012 h-1, Ea=(93.5±2.2) kJ ·mol-1 and m=1.18±0.19, were comparable to those from isothermal studies at constant humidity, A=(1.71±0.35)×1012 h-1, Ea=(94.9±0.7) kJ ·mol-1 and m=1.20±0.02. Since the programmed humidifying and non-isothermal experiments save time, labor and materials, it is suggested that the new experimental method can be used to investigate the stability of drugs unstable to both moisture and heat, instead of many classical isothermal experiments at constant humidity.

Extraction, Molecular Weight Distribution, and Antioxidant Activity of Oligosaccharides from Longan (Dimocarpus Longan Lour.) Pulp

Xian Lin,Jinling Chen,Gengsheng Xiao,Yujuan Xu,Daobang Tang,Jijun Wu,Jing Wen,Weidong Chen 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.3

Ultrasonic-microwave synergistic extraction (UMSE) was optimized for the extraction of oligosaccharides from longan pulp (OLP). Box-Behnken design was used to evaluate the effects of temperature (35-55oC), ultrasonic time (5-25 min), and water to material ratio (10-30 mL/g) on the extraction efficiency of crude OLP. A regression model was developed and its validity was statistically demonstrated. Significant interaction between temperature and water to material ratio was observed. The following optimal conditions for the extraction yield of crude OLP were determined: extraction temperature 55oC, ultrasonic time 18.52 min, and water to material ratio 10 mL/g. The extracted OLP were purified for the determination of molecular weight distribution and antioxidant activity. Results of matrix-assisted laser desorption ionization time-of-flight mass spectrometry revealed that the molecular weight distribution of the purified OLP ranged from m/z 495.138 to 795.511. The purified OLP exhibited a dose-dependent behavior in 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity.

Inhibitory Effects of 3-Bromopyruvate on Human Gastric Cancer Implant Tumors in Nude Mice

Xian, Shu-Lin,Cao, Wei,Zhang, Xiao-Dong,Lu, Yun-Fei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Background: Gastric cancer is a common malignant tumor. Our previous study demonstrated inhibitory effects of 3-bromopyruvate (3-BrPA) on pleural mesothelioma. Moreover, we found that 3-BrPA could inhibit human gastric cancer cell line SGC-7901 proliferation in vitro, but whether similar effects might be exerted in vivo have remained unclear. Aim: To investigate the effect of 3-BrPA to human gastric cancer implant tumors in nude mice. Materials and Methods: Animals were randomly divided into 6 groups: 3-BrPA low, medium and high dose groups, PBS negative control group 1 (PH7.4), control group 2 (PH 6.8-7.8) and positive control group receiving 5-FU. The TUNEL method was used to detect apoptosis, and cell morphology and structural changes of tumor tissue were observed under transmission electron microscopy (TEM). Results: 3-BrPA low, medium, high dose group, and 5-FU group, the tumor volume inhibition rates were 34.5%, 40.2%, 45.1%, 47.3%, tumor volume of experimental group compared with 2 PBS groups (p<0.05), with no significant difference between the high dose and 5-FU groups (p>0.05). TEM showed typical characteristics of apoptosis. TUNEL demonstrated apoptosis indices of 28.7%, 39.7%, 48.7% for the 3-BrPA low, medium, high dose groups, 42.2% for the 5-FU group and 5% and 4.3% for the PBS1 (PH7.4) and PBS2 (PH6.8-7.8) groups. Compared each experimental group with 2 negative control groups, there was significant difference (p<0.05); there was no significant difference between 5-FU group and medium dose group (p>0.05), but there was between the 5-FU and high dose groups (p<0.05). Conclusions: This study indicated that 3-BrPA in vivo has strong inhibitory effects on human gastric cancer implant tumors in nude mice.

Antioxidant Flavone Glycosides from the Root of Pteroxygonum giraldii

Bao-Lin Li,Lin-Ling Jiang,Hui-Chun Wang,Zhan-Jun Yang,Xi-Quan Zhang,Hong-Mei Gu,Xian-Hua Tian 대한화학회 2009 Bulletin of the Korean Chemical Society Vol.30 No.7

Two new flavone glycosides, giraldiin A and B, together with three known compounds, annulatin, myricetin 3-O-α-L-rhamnopyranoside and gallic acid, were isolated from the ethanol extract of the root of Pteroxygonum giraldii Damm. et Diels. The structures of giraldiin A and B are designated as 3'-(α-L-arabinopyranosyloxy)-4',5,5',7-tetrahydroxy-3-methoxyflavone and 4'-(β-D-glucopyranosyloxy)-5,5',7-trihydroxy-2',3-dimethoxyflavone, respectively,on the basis of detailed spectroscopic analyses. The free radical scavenging activity of giraldiin A was evaluated by decolouring spectrophotometry of pentamethine cyanine dye (Cy5) with Fe2+-H2O2 Fenton radical generating system. The results indicated the hydroxyl free radical scavenging activity of giraldiin A (ED50 = 23.7 nmol/mL) is higher than that of some known antioxidants such as rutin, puerarin, daidzein and 2,6-di-tertbutyl-4-methylphenol.

Ischemic postconditioning protects cardiomyocytes against ischemia/reperfusion injury by inducing MIP2

Hong-Lin Zhu,Kang-Kai Wang,Xing Wei,Shun-Lin Qu,Chi Zhang,Xiao-Xia Zuo,Yan-Sheng Feng,Qi Luo,Guang-Wen Chen,Mei-Dong Liu,Lei Jiang,Xian-Zhong Xiao 생화학분자생물학회 2011 Experimental and molecular medicine Vol.43 No.8

Cardiomyocytes can resist ischemia/reperfusion (I/R)injury through ischemic postconditioning (IPoC)which is repetitive ischemia induced during the onset of reperfusion. Myocardial ischemic preconditioning up-regulated protein 2 (MIP2) is a member of the WD-40family proteins, we previously showed that MIP2 was up-regulated during ischemic preconditioning (IPC). As IPC and IPoC engaged similar molecular mechanisms in cardioprotection, this study aimed to elucidate whether MIP2 was up-regulated during IPoC and contributed to IPoC-mediated protection against I/R injury. The experiment was conducted on two models,an in vivo open chest rat coronary artery occlusion model and an in vitro model with H9c2 myogenic cells. In both models, 3 groups were constituted and randomly designated as the sham, I/R and IPoC/hypoxia postconditioning (HPoC) groups. In the IPoC group, after 45 min of ischemia, hearts were allowed three cycles of reperfusion/ischemia phases (each of 30 s duration)followed by reperfusion. In the HPoC group, after 6 h of hypoxia, H9c2 cells were subjected to three cycles of 10 minute reoxygenation and 10 minute hypoxia followed by reoxygenation. IPoC significantly reduced the infarct size, plasma level of Lactate dehydrogenase and creatine kinase MB in rats. 12 h after the reperfusion,MIP2 mRNA levels in the IPoC group were 10 folds that of the sham group and 1.4 folds that of the I/R group. Increased expression of MIP2 mRNA and attenuation of apoptosis were similarly observed in the HPoC group in the in vitro model. These effects were blunted by transfection with MIP2 siRNA in the H9c2cells. This study demonstrated that IPoC induced protection was associated with increased expression of MIP2. Both MIP2 overexpression and MIP2 suppression can influence the IPoC induced protection.

Crystallization and melting behavior of polypropylene in b-PP/polyamide 6 blends containing PP-g-MA

Zhidan Lin,Zixian Guan,Baofeng Xu,Chao Chen,Guangheng Guo,Jiaxian Zhou,Jiaming Xian,Lin Cao,Yueliang Wang,Mingqing Li,Wei Li 한국공업화학회 2013 Journal of Industrial and Engineering Chemistry Vol.19 No.2

In this research, we used a twin-screw extruder to melt and blend PP-g-MA compatibilizer with bpolypropylene (PP)/polyamide 6 (PA6). The influences of the PA6 and PP-g-MA contents in PP/PA6 blends on crystallization and melting behavior of PP phase and morphology were investigated. The results showed that, when PP-g-MA copolymer was added to the b form of nucleated PP/PA6 blends, the anhydride groups in PP-g-MA and PA6 terminal amine groups react to form PP-g-PA graft copolymer in a two-phase interface. This reduces the interfacial tension, improves the interfacial adhesion, and reduces the size of PA6 domains in the blend. The generated PP-g-PA graft copolymer wrapped PA6 phase and buried the anhydride groups of PP-g-MA. When the proportion of PP-g-MA and PA6 was between 0.5 and 0.75, there was no longer interfering to the formation of b-crystals in the PP phase. The content of bcrystal of PP phase in blends was found to reach as large as 85.9%.

Detection of circulating tumor cellswith microbeads in a microfluidic device

Ming Xian Lin,Kyung-A Hyun,Hui-Sung Moon,Tae Seok Sim,Jeong-Gun Lee,Jae Chan Park,Hyo-Il Jung 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.3

Evaluation of the Stability of Aspirin in Solid State by the Programmed Humidifying and Non-isothermal Experiments

Zhan, Xian-Cheng,Tao, Jian-Lin,Li, Lin-Li 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.3

single pair of experiments, one with programmed humidity control and the other non-isothermal, rather than many standard isothermal studies, each at constant relative humidity. In experiments, we adopted the acid-base back titration method to measure the content of aspirin in the presence of its degradation products. It was found that the degradation of aspirin could be expressed as In[($C_o-c$)/c]=kt+D, where D was a lag time item not related to humidity and temperature. The relationship between the degradation rate constant k and humidity $H_r$, and temperature T could be described as Arrhenius equation multiplied by an exponential item of relative humidity: k= A . exp($mH_r$)${\cdot}$exp(-($E_a/RT$)), where A, $E_a$ and m were the pre-exponential factor, observed activation energy, and a parameter related to humidity, respectively. The results obtained from the programmed humidifying and non-isothermal experiments, A=$(1.09{\pm}2.04){\times}10^{12}\;h^{-1}$, $E_a=(93.5{\pm}2.2)\;kJ{\cdot}mol^{-1}$ and m=$1.18{\pm}O.19$, were comparable to those from isothermal studies at constant humidity, A=$(1.71{\pm}o.35){\times}10^{12}\;h^{-1}$, $E_a=(94.9{\pm}0.7)\;kJ{\cdot}mol^{-1}$ and m=$1.20{\pm}0.02$. Since the programmed humidifying and non-isothermal experiments save time, labor and materials, it is suggested that the new experimental method can be used to investigate the stability of drugs unstable to both moisture and heat, instead of many classical isothermal experiments at constant humidity.

Effect of Preoperative Tumour Under-Staging on the Long-Term Survival of Patients Undergoing Radical Gastrectomy for Gastric Cancer

Mi Lin,Qi-Yue Chen,Chao-Hui Zheng,Ping Li,Jian-Wei Xie,Jia-Bin Wang,Jian-Xian Lin,Chang-Ming Huang 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose This study aimed to evaluate the effect of preoperative tumor staging deviation (PTSD) on the long-term survival of patients undergoing radical gastrectomy for gastric cancer (RGGC). Materials and Methods Clinicopathological data of 2,346 patients who underwent RGGC were retrospectively analyzed. The preoperative tumor-lymph node-metastasis (TNM) under-staging group (uTNM) comprised patients who had earlier preoperative TNM than postoperative TNM, and the no preoperative under-staging group (nTNM) comprised the remaining patients. Results There were 1,031 uTNM (44.0%) and 1,315 nTNM cases (56.0%). Cox prognostic analysis revealed that PTSD independently affected the overall survival (OS) after surgery. The 5-year OS was lower in the uTNM group (41.8%) than in the nTNM group (71.6%). The patients less than 65 years old, with lower American Society of Anaesthesiologists score, 2-5 cm tumor located at the lower stomach, and cT1 or cN0 preoperative staging would more likely undergo D1+ lymph node dissection (LND) in uTNM (p < 0.05). Logistic analyses revealed that tumor size > 2 cm and body mass index ≤ 22.72 kg/m2 were independent risk factors of preoperative TNM tumor under-staging in patients with cT1N0M0 staging (p < 0.05). Conclusion Underestimated tumor staging is not rare, which possibly results in inadequate LND and affects the long-term survival for patients undergoing RGGC. D2 LND should be carefully performed in patients who are predisposed to this underestimation.

Expression and Functional Role of ALDH1 in Cervical Carcinoma Cells

Rao, Qun-Xian,Yao, Ting-Ting,Zhang, Bing-Zhong,Lin, Rong-Chun,Chen, Zhi-Liao,Zhou, Hui,Wang, Li-Juan,Lu, Huai-Wu,Chen, Qin,Di, Na,Lin, Zhong-Qiu Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Tumor formation and growth is dictated by a very small number of tumor cells, called cancer stem cells, which are capable of self-renewal. The genesis of cancer stem cells and their resistance to conventional chemotherapy and radiotherapy via mechanisms such as multidrug resistance, quiescence, enhanced DNA repair abilities and anti-apoptotic mechanisms, make it imperative to develop methods to identify and use these cells as diagnostic or therapeutic targets. Aldehyde dehydrogenase 1 (ALDH1) is used as a cancer stem cell marker. In this study, we evaluated ALDH1 expression in CaSki, HeLa and SiHa cervical cancer cells using the Aldefluor method to isolate ALDH1-positive cells. We showed that higher ALDH1 expression correlated with significantly higher rates of cell proliferation, microsphere formation and migration. We also could demonstrate that SiHa-ALDH1-positive cells were significantly more tumorigenic compared to SiHa-ALDH1-negative cells. Similarly, SiHa cells overexpressing ALDH1 were significantly more tumorigenic and showed higher rates of cell proliferation and migration compared to SiHa cells where ALDH1 expression was knocked down using a lentivirus vector. Our data suggested that ALDH1 is a marker of cervical cancer stem cells and expand our understanding of its functional role.