• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.1069-1072
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• 2015

Background: Colorectal cancer (CRC) is an important cause of mortality and morbidity in many communities worldwide. This population based study was conducted to assess determinants of colorectal mortality in Iranian patients. Materials and Methods: A cohort of 1,127 cases of confirmed colorectal cancer registered in a population based registry covering 10 referral hospital in Tehran, Iran, were followed for five years. Information about tumor characteristics, smoking status and family history were collected at base line and survival status were followed every six months by contacting patient or next of kin (if patients died during the follow-up). The cause of death for each case was validated by verbal autopsy and referring to patient medical records at the time of death. The data were analyzed by Stata software using univariate and multivariate analysis (Cox regression). In building the model a p value of less than 5% was considered as significant. Results: The age at diagnosis was $53.5{\pm}14$ years. Sixty one percent were male. Colorectal mortality among the patients was 96.9 person-years among men and 83 person-years among women. Seventy five percent of patients lived for 2.72 years, 50% for 5.83, and 25% for 13 years after the diagnosis of colorectal cancer. The age at diagnosis was significantly different between men and women (p<0.03). Higher tumor grade predicted higher death rate; the adjusted hazard ratios were 1.79 (95%CI, 0.88-3.61), 2.16 (95%CI, 1.07-4.37), and 3.1 (95%CI, 1.51-6.34) for grades II, III, and IV respectively when they were compared with grade I as reference. Ethnicity, marital status, family history of cancer, and smoking were related to survival with different degrees of magnitude. Conclusions: Among many factors related to survival among the colorectal patients, tumor grade and smoking showed the highest magnitudes of association.

• Journal of Periodontal and Implant Science
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• v.51 no.3
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• pp.163-178
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• 2021

Purpose: The aim of this study was to evaluate clinical factors affecting the longevity of fixed retainers and the influence of fixed retainers on periodontal health in periodontitis patients. Methods: In total, 52 patients with at least 2 years of follow-up after periodontal and orthodontic treatment were included in this study. After scaling and root planing, orthodontic treatment with fixed appliances or clear aligners was performed. Fixed retainers with twist-flex stainless steel wires were bonded to the palatal or lingual sides of anterior teeth. Changes in clinical parameters, including the plaque index, gingival index, calculus index (CI), probing pocket depth, and radiographic bone levels, were evaluated before bonding of fixed retainers and at a 12-month follow-up. Cumulative survival rates (CSRs) for retainer failure were evaluated according to sex, site, CI, stage of periodontitis, and the severity of the irregularity with the log-rank test and hazard ratios (HRs). Results: Twelve months after bonding of fixed retainers, improvements were observed in all clinical parameters except CI and radiographic bone gain. The overall CSR of the retainers with a CI <1 at the 12-month follow-up after bonding of fixed retainers was significantly higher than that of the retainers with a CI ≥1 at the 12-month follow-up (log-rank test; P<0.001). Patients with stage III (grade B or C) periodontitis had a higher multivariate HR for retainer failure (5.4; 95% confidence interval, 1.22-23.91; P=0.026) than patients with stage I (grade A or B) periodontitis. Conclusions: Although fixed retainers were bonded in periodontitis patients, periodontal health was well maintained if supportive periodontal treatment with repeated oral hygiene education was provided. Nonetheless, fixed retainer failure occurred more frequently in patients who had stage III (grade B or C) periodontitis or a CI ≥1 at 12-month follow-up after bonding of fixed retainers.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.159-163
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• 2013

Background: This study used Surveillance, Epidemiology and End Results (SEER) pancreatic cancer data to identify predictive models and potential socio-economic disparities in pancreatic cancer outcome. Materials and Methods: For risk modeling, Kaplan Meier method was used for cause specific survival analysis. The Kolmogorov-Smirnov's test was used to compare survival curves. The Cox proportional hazard method was applied for multivariate analysis. The area under the ROC curve was computed for predictors of absolute risk of death, optimized to improve efficiency. Results: This study included 58,747 patients. The mean follow up time (S.D.) was 7.6 (10.6) months. SEER stage and grade were strongly predictive univariates. Sex, race, and three socio-economic factors (county level family income, rural-urban residence status, and county level education attainment) were independent multivariate predictors. Racial and socio-economic factors were associated with about 2% difference in absolute cause specific survival. Conclusions: This study s found significant effects of socio-economic factors on pancreas cancer outcome. These data may generate hypotheses for trials to eliminate these outcome disparities.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1403-1407
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• 2007

The bogie of Rolling Stock is the basic rolling component. It operates the train body, guides the body considering various tracks and offers comfort to passengers. We can verify the safety level of bogie about all factors through the first -grade scenario of Preliminary Hazard Analysis, but especially the horizontal acceleration sensor, equipped in each power bogie and trailer bogie, is the device, which makes it possible to test bogie instability and uncomfortable body movements by the method, similar to actual train driving, and in this context the necessity of this device becomes important. This paper would classify the main functions of driving sub system and examine the reliability, availability, maintainability and safety, which are main factors of RAMS. Especially, we would realize the bogie instability sensor with a simulator and offer the content in analyzing the data by the statistical method, which are obtained through the connected test with OBCS.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10a
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• pp.655-657
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• 2004

본 논문은 안전등급 제어 기 기(Programmable Logic Controller) 에서 동작하는 실시간 운영체제의 안전성을 요구사항 단계에서 평가할 수 있는 검토항목을 개발하고 HAZOP(Hazard and Operability) 을 이용하여 현재 개발중인 PLC 운영체제에 적용한 경험 을 기술한다. HAZOP은 화학공장과 같은 산업에서 안전성을 평가하기 위한 방법으로 사용했던 방법론이다. 원자력발전소에 적용하기 위해 운영체제가 갖추어야 할 안전성 요건은 NUREG-0800의 BTP-14(Branch Technical Position)의 소프트웨어 기능특성 및 공정특성에 기술되어 있다. 이러한 기능적인 특성을 정확도, 신뢰성, 타이밍/사이징, 기능성, 강인성, 보안성 항목으로 나누고 세부적인 검토리스트를 만들어 HAZOP을 적용하여 평가하였다.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3945-3951
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• 2016

Background: Whether concurrent chemotherapy treatment is superior to radiotherapy alone as an adjuvant regimen for postoperative cervical carcinoma with risk factors remains controversial. Materials and Methods: A literature search strategy examined Pubmed, Embase, the Cochrane Library, the China National Knowledge Internet Web, the Chinese Biomedical Database and the Wanfang Database. Article reference lists and scientific meeting abstracts were also screened. Controlled trials comparing concurrent chemoradiotherapy versus radiotherapy alone in postoperative cervical cancer were included. The methodological quality of non-randomized controlled trials was evaluated using the Newcastle-Ottawa Scale. Randomized controlled studies were evaluated with the Cochrane handbook. A meta-analysis was performed with RevMan 5.3. Results: A total of 1,073 patients from 11 clinical trials were analysed, with 582 patients in the concurrent chemoradiotherapy group and 491 patients in the radiotherapy group. Hazard ratios (HR) of 0.47 (95% CI 0.31-0.72) and 0.50 (95% CI 0.35-0.72) were observed for overall survival and progression-free survival, indicating a benefit from the additional use of concurrent chemotherapy. Subgroup analyses demonstrated that cervical cancer with high risk factors significantly benefitted from concurrent chemotherapy when examining overall survival (HR 0.44, 95% CI 0.28-0.67) and progression-free survival (HR 0.48, 95% CI 0.33-0.70), but patients with intermediate risk factors showed no benefit from concurrent chemotherapy in overall survival (HR 1.72, 95% CI 0.28-10.41) and progression-free survival (HR 1.09, 95% CI 0.19-6.14). No significant differences were observed for grade 3-4 anaemia (risk ratio (RR) 3.87, 95% CI 0.69-21.84), grade 3-4 thrombocytopenia (RR 3.04, 95% CI 0.88-10.58), grade 3-4 vomiting or nausea (RR 1.71, 95% CI 0.27-10.96), or grade 3-4 diarrhoea (RR 1.40, 95% CI 0.69-2.83). Significant differences were observed for grade 3-4 neutropenia in favour of the radiotherapy group (RR 7.23, 95% CI 3.94-13.26). Conclusions: In conclusion, concurrent chemoradiotherapy improves survival in postoperative cervical cancer with high risk factors but not in those with intermediate risk factors.

• Journal of Chest Surgery
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• v.40 no.10
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• pp.680-684
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• 2007

Background: Complete surgical resection is the most effective treatment for stage IB non-small cell lung cancer (NSCLC). Recurrence accounts for the disappointing survival rates after resection. There has been renewed interest in adjuvant therapy after complete resection. Appropriate selection of effective adjuvant therapy will depend on the prognostic factors for recurrence. Material and Method: The study included 114 patients with completely resected stage IB NSCLC. The variables selected for the study were gender, age, the type of resection, cell type, the degree of differentiation, the tumor size and the presence of visceral pleura invasion. The Kaplan-Meier method was used to estimate the survival and disease-free survival rate. The results were compared using the log rank test. Multivariate analysis was performed by Cox's proportional hazard model. Two-sided p-valves < 0.05 were considered to be statistically significant. Result: The 3-year overall survival and the disease-free survival rates were 87.0% and 79.4%, respectively. The degree of differentiation showed a significant influence on disease-free survival according to the univariate analysis. According to the multivariate analysis, a poor grade of differentiation was a significant poor prognostic factor. Conclusion: These results demonstrate that poor differentiation may be a poor prognostic factor for patients with completely resected IB NSCLC. Therefore, the patients with a poor grade of differentiation may require adjuvant therapies.

• Journal of the Korean earth science society
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• v.34 no.7
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• pp.605-614
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• 2013

Most steep slope failures tend to take place in geographically unstable areas. Mt. Baekdusan is known as a potentially active volcano in a typical mountainous terrain. This study prepared a digital elevation model of Mt. Baekdusan area and created a hazard map based on topographical factors and structural lineament analysis. Factors used in vulnerability analysis included geographical data involving aspect and slope distribution, as well as contributory area of upslope, tangential gradient curvature, profile gradient curvature, and the distribution of wetness index among the elements that comprise topography. In addition, the stability analysis was conducted based on the lineament intensity map. Concerning the disaster vulnerability of Mt. Baekdusan region, the south and south west area of Mt. Baekdusan has a highest risk of disaster (grade 4-5) while the risk level decreases in the north eastern region.

• Journal of Preventive Medicine and Public Health
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• v.51 no.5
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• pp.242-247
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• 2018

Objectives: To examine survivorship disparities in demographic factors and risk status for non-muscle-invasive bladder cancer (NMIBC), which accounts for more than 75% of all urinary bladder cancers, but is highly curable with early identification and treatment. Methods: We used the US National Cancer Institute's Surveillance, Epidemiology, and End Results registries over a 19-year period (1988-2006) to examine survivorship disparities in age, sex, race/ethnicity, and marital status of patients and risk status classified by histologic grade, stage, size of tumor, and number of multiple primary tumors among NMIBC patients (n=29 326). We applied Kaplan-Meier (K-M) and Cox proportional hazard methods for survival analysis. Results: Among all urinary bladder cancer patients, the majority of NMIBCs were in male (74.1%), non-Latino white (86.7%), married (67.8%), and low-risk (37.6%) to intermediate-risk (44.8%) patients. The mean age was 68 years. Survivorship (in median life years) was highest for non-Latino white (5.4 years), married (5.4 years), and low-risk (5.7 years) patients (K-M analysis, p<0.001). We found significantly lower survivorship for elderly, male (female hazard ratio [HR], 0.96), Latino (HR, 1.20), and unmarried (married HR, 0.93) patients. Conclusions: Survivorship disparities were ubiquitous across age, sex, race/ethnicity, and marital status groups. Non-white, unmarried, and elderly patients had significantly shorter survivorship. The implications of these findings include the need for a heightened focus on health policy and more organized efforts to improve access to care in order to increase the chances of survival for all patients.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4527-4531
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• 2016

Background: PTEN protein is one of the most important tumour suppressor factors which is detectable by immunohistochemistry. The goal of the present study was to investigate the prognostic role of PTEN gene expression in breast cancer patients. Materials and Methods: This descriptive-analytical study was conducted on 100 breast cancer patients referred to Sabzevar hospitals in the north-east of Iran between 2010 and 2011, who were followed up to 2015. PTEN gene expression in tissue samples was determined using specific monoclonal antibodies and data were analyzed using Chi-square test and Fisher's exact test. Patient survival was analyzed after 4 years of follow-up using the Cox regression model. Results: PTEN gene expression was evident in 70 of 100 cnacer samples but was found at high levels in all non-cancer samples. There was an inverse significant relationship between PTEN gene expression and tumour stage or tumour grade (p<0.001). The expression of PTEN in invasive ductal tumours was lower than in non-invasive tumours. There was also an inverse significant relationship between the hazard of death and PTEN gene expression (p<0.001). In addition, there was an inverse significant relationship between tumour stage and hazard of death (p<0.001). Conclusion: These findings indicate that lack of PTEN gene expression can be a sign of a worse prognosis and poor survival in breast cancer cases.