• Journal of Life Science
• /
• v.26 no.7
• /
• pp.847-854
• /
• 2016

Cordycepin, a derivative of the nucleoside adenosine, is one of the active components extracted from fungi of genus Cordyceps, and has been shown to have many pharmacological activities. In this study, we investigated the effects of cordycepin on proliferation and apoptosis of human gastric cancer AGS cells, and its possible mechanism of action. Treatment of cordycepin resulted in significant decrease in cell viability of AGS cells in a concentration-dependent manner. A concentration-dependent apoptotic cell death was also measured by agarose gel electrophoresis and flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled cordycepin treatment resulted in an enhanced expression of tumor necrosis factor-related apoptosis-inducing ligand, death receptor 5 and Fas ligand. Furthermore, up-regulation of pro-apoptotic Bax, and down-regulation of anti-apoptotic Bcl-2 and Bcl-xL expression were also observed in cordycepin-treated AGS cells. These were followed by activation of caspases (caspase-9, -8 and -3), subsequently leading to poly (ADP-ribose) polymerase cleavage. Taken together, these findings indicate that cordycepin induces apoptosis in AGS cells through regulation of multiple apoptotic pathways, including death receptor and mitochondria. Although further mechanical studies are needed, our results revealed that cordycepin can be regarded as a new effective and chemopreventive compound for human gastric cancer treatment.

• Journal of the Korean Data and Information Science Society
• /
• v.22 no.1
• /
• pp.89-97
• /
• 2011

The aims of this study were to propose a method of estimation for mean residual life function (MRLF) from conditional survival function using the Buckley and James's (1979) pseudo random variables, and then to assess the performance of the proposed method through the simulation studies. The mean squared error (MSE) of proposed method were less than those of the Cox's proportional hazard model (PHM) and Beran's nonparametric method for non-PHM case. Futhermore in the case of PHM, the MSE's of proposed method were similar to those of Cox's PHM. Finally, to evaluate the appropriateness of practical use, we applied the proposed method to the gastric cancer data. The data set consist of the 1, 192 patients with gastric cancer underwent surgery at the Department of Surgery, K-University Hospital.

• Journal of the Korean Data and Information Science Society
• /
• v.27 no.5
• /
• pp.1169-1182
• /
• 2016

Cancer is a typical cause of death in Korea that becomes a major issue in health care. According to Cause of Death Statistics (2014) by National Statistical Office, SMRs (standardized mortality rates) in Busan were counted as the highest among all cities. In this paper, we used data of Busan Regional Cancer Center to estimate the extent of the cancer incidence rate and cancer mortality rate. The data are considered in small areas of administrative units such as Gu/Dong from years 2003 to 2009. All cancer including four major cancers (stomach cancer, colorectal cancer, lung cancer, liver cancer) have been analyzed. We carried out model selection and parameter estimation using spatial multi-level model incorporating a spatial correlation. For the spatial effects, CAR (conditional autoregressive model) has been assumed.

• Journal of the Korean Data and Information Science Society
• /
• v.26 no.6
• /
• pp.1317-1325
• /
• 2015

There are two types of clinical research to figure out risk factor for disease using collected data. One is prospective study to approach the subjects from the present time and the other is retrospective study to find the risk factor using the subject's information in the past. Both approached and study design are different but the purpose of the two studies is to identify a significant difference between two groups and to find out what the variables to influence groups. Especially when comparing the two groups in clinical research, we have to look at the difference between the impact clinical variables by group while controlling the influence of the baseline characteristics variables such as age and sex. However, in the retrospective study, the difference of baseline characteristic variables can occur more frequently because the past records did not randomly assign subjects into two groups. In clinical data analysis use covariates to solve this problem. Typically, the analysis method using the analysis of covariance of variance, adjusted model, and propensity score matching method. This study is introduce the way of equality adjustment between groups data analysis using covariates in retrospective clinical studies and apply it to the recurrence of gastric cancer data.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.8
• /
• pp.1079-1083
• /
• 2008

The purposes of this study were aimed to evaluate the antioxidant and antiproliferative activities of water, methanol, and 70% acetone extracts from pepper leaves. The antioxidant activity was evaluated by ABTS and DPPH radical scavenging activities, reducing power, and chelating effect. Moreover, the effects of the extracts on cell proliferation of breast (MCF7), colon (HCT116), and gastric (MKN45) tumor cells were investigated. Higher extraction yields were obtained with methanol than with 70% acetone and water. Among the three different solvents, 70% acetone extract showed the highest polyphenolic contents. 70% acetone extracts showed higher antioxidant activities compared with other extracts. Also, 70% acetone extract of pepper leaves exhibited higher antiproliferative activity (>80%) against HCT116 and MKN45 cells compared with other samples at the concentration of 1 mg/mL. These results indicate that pepper leaves may serve as potential dietary sources of natural antioxidants and antiproliferative substances.

• Food Science and Preservation
• /
• v.20 no.5
• /
• pp.691-698
• /
• 2013

The biological activities of Smilax china L. rhizome (SCR), hot water (SCRW) and 70% ethanol extract (SCRE) were analyzed. The total phenolic contents of SCRW and SCRE were 51.7 and 100.5 mg/g, respectively. The measured flavonoid content of SCRW ($67.7{\mu}g/g$) was almost double that of SCRE ($31.7{\mu}g/g$). SCRE ($IC_{50}=42.4{\mu}g/mL$) exhibited stronger antioxidant activity in the DPPH system than the positive control ${\alpha}$-tocopherol ($71.3{\mu}g/mL$) or butylated hydroxy anisole ($53.8{\mu}g/mL$) did. SCRE ($IC_{50}=50.3{\mu}g/mL$) also showed stronger ABTS radical scavenging activity, as did ${\alpha}$-tocopherol ($67.1{\mu}g/mL$). The SOD-like activity and Tyrosinase inhibition activity of SCRW and SCRE showed almost the same pattern. The best SOD-like activity and tyrosinase inhibition activity were measured as 24.9% and 20.3% in SCRW at $1,000{\mu}g/mL$, respectively. The cytotoxic effects of the SCR extracts were analyzed via MTT assay on human cancer and normal cells. SCRW and SCRE did not show cytotoxicity up to the concentration of $1,000{\mu}g/mL$ against the normal human cell line HEK293. Against human breast cancer cells (MCF-7), SCRW inhibited MCF-7 growth (by 27.6%) better than the anticancer drug cyclophosphamide (15.5%) at $1,000{\mu}g/mL$. SCRE ($1,000{\mu}g/mL$) inhibited the growth of human lung cancer cells A549 (37.6%) and human stomach cancer cells AGS (53.6%) more effective than did SCRW (21.0% and 35.4%) or CPA (22.2% and 31.7%). These results suggest the potential use of SCRE and SCRW as an excellent antioxidant and antiproliferative substance, respectively.

• Journal of Digital Convergence
• /
• v.10 no.3
• /
• pp.219-225
• /
• 2012

This study is analyzed the implementation of medical aid for patients over 65 years of age who are among the discharged from hospitals with the capacity of over 100 beds. I have analyzed it with the data from an in-depth study of injury surveillance of discharged patients from hospitals done in a national project in 2004. After analyzing the results of the data from the beginning of this national project to the data collected in 2008, I could get the results that the rate of discharged patients over 65 years of age increased every year. Among them, the rate of discharged women was higher than that of the men, and the rate of deaths while at the hospital for patients over 65 years of age was higher than that of patients less than 65 years of age. The rate of operations done on patients over 65 was lower than that of patients under 65 years of age. The results of a diagnosis of popular symptoms showed that the rate of the diagnosis of cerebral infraction and structure of the heart at the circulatory organ was higher. In addition, the rate of the diagnosis of lung cancer, pneumonia, and chronic obstructive lung disease was higher, as well as the rates of gastric cancer, diabetes, liver cancer, and colorectal cancer. The results showed that the operation of the nerve system or cardiovascular system were higher. Therefore, according to this result, we should prioritize and allocate resources to the elderly people when setting up a management policy. And also, we should promote healthcare for elderly people after considering the characteristics of the implementation of medical aid in preparation of a super-aged society.

• The Korean Journal of Applied Statistics
• /
• v.22 no.3
• /
• pp.585-594
• /
• 2009

Researchers of microarray experiment transpose processed images of raw data to possible data of statistical analysis: it is preprocessing. Preprocessing of microarray has image filtering, imputation and normalization. There have been studied about several different methods of normalization and imputation, but there was not further study on the order of the procedures. We have no further study about which things put first on our procedure between normalization and imputation. This study is about the identification of differentially expressed genes(DEG) on the order of the preprocessing steps using two-dye cDNA microarray in colon cancer and gastric cancer. That is, we check for compare which combination of imputation and normalization steps can detect the DEG. We used imputation methods(K-nearly neighbor, Baysian principle comparison analysis) and normalization methods(global, within-print tip group, variance stabilization). Therefore, preprocessing steps have 12 methods. We identified concordance measure of DEG using the datasets to which the 12 different preprocessing orders were applied. When we applied preprocessing using variance stabilization of normalization method, there was a little variance in a sensitive way for detecting DEG.

• Journal of Digital Convergence
• /
• v.11 no.8
• /
• pp.281-291
• /
• 2013

This study is the secondary statistical analysis calculating the quality of life of patients with cancer by giving the integrative weight based on National Health and Nutrition Examination Survey data of the Centers for Disease Control for five years from 2007 to 2011 for the first time in Korea. The results of measurement showed that the number of cancer patients was 201, which accounted for about 0.8 % of 26,260 subjects. The quality of life of cancer patients was higher when they had lower age(p<0.0001), more professional occupations(p<0.0001), and higher educational history(p=0.0002). When they lived in apartment(p<0.0001), got unmarried(p<0.0001), the quality of life was higher. In particular, the measurement of quality of life of cancer patients based on type of health insurance was the result of new study for the first time in Korea.

• Journal of Digital Convergence
• /
• v.11 no.10
• /
• pp.459-467
• /
• 2013

The purpose of this study was to identify the differences in medical care utilization by regional economic status using the National Hospital Discharge Patients Injury Survey. In order to determine economic status of each region, 234 cities and counties were categorized 5 quintiles according to their financial self-reliance ratio. The main results are as follows. First, low economic region has high age-standardized admission rate and standardized mortality rate. Second, of 16 major diseases, cerebrovascular and heart diseases, lung cancer, and stomach cancer reported greater changes in standardized mortality rate by regional economic status. Third, the rate of admission via emergency room in low economic region is higher than that of high economic region. Lastly, in the major illnesses, lower economic status led to an increase in average length of stay. Therefore, In order to bridge the gap in health inequality across regions, a regional medical policy tailored for each region and characteristics of the economic status should be established.