• Asian-Australasian Journal of Animal Sciences
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• v.24 no.5
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• pp.603-609
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• 2011

Telomeres are special structures at the ends of eukaryotic chromosomes. Vertebrate telomeres consist of tandem repeats of conserved TTAGGG sequence and associated proteins. Birds are interesting models for molecular studies on aging and cellular senescence because of their slow aging rates and longer life spans for their body size. In this longitudinal study, we explored the possibility of using telomeres as an age-marker to predict age in Single Comb White Leghorn layer chickens. We quantified the relative amount of telomeric DNA in isolated peripheral blood lymphocytes by the Quantitative Fluorescence in situ Hybridization technique on interphase nuclei (IQ FISH) using telomere-specific DNA probes. We found that the amount of telomeric DNA (ATD) reduced significantly with an increase in chronological age of the chicken. Especially, the telomere shortening rates are greatly increased in growing individuals compared to laying and old-aged individuals. Therefore, using the ATD values obtained by IQ FISH we established the possibility of age prediction in chickens based on the telomere theory of aging. By regression analysis of the ATD values at each age interval, we formulated an equation to predict the age of chickens. In conclusion, the telomeric DNA values by IQ FISH analyses can be used as an effective age-marker in predicting the chronological age of chickens. The study has implications in the breeding and population genetics of poultry, especially the reproductive potential.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3951-3955
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• 2015

Background: Colorectal cancer mortality has started to decrease in several developed countries in Asia. The current study aimed to present the long-term trends in colorectal cancer mortality in Korea using joinpoint analysis and age-period-cohort modeling. Materials and Methods: The number of colorectal cancer deaths and the population for each 5-year age group were obtained from Statistics Korea for the period 1984-2013 for adults 30 years and older. Joinpoint regression analysis was conducted to determine changes in trends in age-standardized mortality rates, and age-period-cohort analysis was performed to describe trends in colorectal cancer mortality using the intrinsic estimator method. Results: In men, the age-standardized mortality rate for colorectal cancer increased from 1984 to 2003, and the mortality rates stabilized thereafter, whereas the mortality rate of colorectal cancer in women has decreased since 2004. The age-specific mortality rate of colorectal cancer increased in both men and women over time, whereas decreases in the age-specific mortality rate in younger cohorts were observed. In the age-period-cohort analysis, old age and recent period were associated with higher mortality for both men and women. The birth cohort born after 1919 showed reduced colorectal cancer mortality in both men and women. Conclusions: Our study showed a recent decreasing trend in colorectal cancer mortality in women and a stable trend in men after 2003-2004. These changes in colorectal cancer mortality may be attributed to birth cohort effects.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3469-3476
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• 2016

Background: The cancer research literature suggests that women, especially premenopausal women, have lower cancer mortality rates than men. However, it is unclear if that is true for populations at all age levels in all countries and what factors affect such sex differences. This paper attempts to fill that gap. Materials and Methods: Sex- and country-specific cancer mortality data were statistically analyzed with particular attention to geographic, social, and economic factors that may affect the sex differences. Results: The sex differences were age and country specific, rather than universal. Premenopausal women actually tend to have a disadvantage compared to men or postmenopausal women. Male cancer mortality appears to be the affecting factor in explaining variations in sex differences. Latitude of residence and literacy rate are the affecting factors in cancer mortality and sex differences. African and Latin American countries tend to have a female disadvantage, while East Asian and Eastern European countries are more likely to have a female advantage. Conclusions: The findings challenge the cancer mortality literature and indicate that the sex differences and their possible causes are more complicated than the current literature suggests. They also highlight the urgency of adapting age- and country- specific health systems and policies to better meet the needs of younger women.

• Clinical and Experimental Pediatrics
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• v.51 no.7
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• pp.690-695
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• 2008

The age-specific anti-hepatitis A virus (HAV) seroprevalence rates in South Korea have changed markedly since the last 2030 years with an improvement in the socio-economic, housing, and environmental-sanitation conditions. These changes are characterized by very low anti-HAV seropositive rates among individuals less than 30 years of age; however, nowadays, most adolescents and young adults at an increased risk of developing symptomatic HAV infections. The Korea Center for Disease Control Sentinel Surveillance System has recently revealed an increase in the incidence of hepatitis A infection since 2001 and has revealed a potential endemic nature of the hepatitis A infection. Hepatitis A vaccines that were introduced in 1997 in Korea have made the current anti-HAV IgG positive rates in children (less than 10 years of age) approximately 50% of the rates observed in Seoul in 2006. However, in the same year, a few children were diagnosed as having anti-HAV IgG antibodies in Busan. This suggests the presence of some difference in the vaccination policy among doctors practicing in Seoul and Busan. Thus, the current recommendation of vaccinating 12-year-old child with HAV vaccination should be emphasized and a new strategy should be developed for the vaccination program to cater to the adolescents and young adults who are not immune, as well as for persons who are at a high risk for hepatitis A viral infection such as military personnel and hospital and day care center employees. Further, urgent hepatitis A vaccinations are also needed in patients with chronic liver diseases.

• Korea journal of population studies
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• v.11 no.1
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• pp.197-203
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• 1988

In order to examine cause-specific mortality in Korea by comparing mortality of Japan, various mortality indicators are calculated using 1995 of ficial statistics of twonations. The mortality measures are cause-specific mortality rate by sex, age, andmarital status, cause-specific age-standardized death rate and potential years of lifelost, and their ratios by sex and nation. Items of major causes of death include allcauses (total deaths),tuberculosis, malignant neoplasm, diabetes mellitushypertensive diseases, heart diseases, cerebrovascular diseases, liver diseasestransport accidents, and suicide. Major characteristics of mortality in Korea are asfollows . (1) Death rates from most causes except suicide are higher in Korea thanJapan and especially death rates from tuberculosis, hypertensive diseases, liverdiseases, and transport accidents are higher for economically active Koreans : (2)Death rates from tuberculosis, liver diseases, transport accidents, and malignantneoplasm are salient for Korean children (3) Sex-differentials in mortality fromliver diseases, tuberculosis , and transport accidents are large for economically activeKoreans, because male mortality is higher than female mortality : (4) Suicide ratesare lower for economically active males, and higher for females aged 10s and 20s inKorea than Japan : (5) Death rates are highest f3r divorced or widowed under 45years of age depending on causes, but death rates from all causes are highest fornever-married of the age 45 and over in Korea : and (6) Sex-differentials inmortality are greatest for widowed in Korea and for divorced in Japan.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.385-390
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• 2014

Background: Lung cancer is the most frequent malignancy of men worldwide. In Ninawa in Iraq, lung cancer ranks first among cancers diagnosed in men. Since no prior studies have been conducted on incidence trends in our population the present investigation of rates during 2000-2010 was therefore performed. Materials and Methods: Registy data for lung cancer cases were collected from the Directorate of Health in Ninawa-Mosul Continuing Medical Education Center. We restricted our analyses to men categorized according to the age groups of 0- 39, 40-49, 50-59, 60-69 and 70+ years. The significance of incidence rate trends during 2000-2010 was tested using Poisson regression. Age-standardized rates (ASR), and age-specific rates per 100,000 population were calculated. Results: A total of 1,206 incident lung cancer were registered among males, accounting for 15.5% of all male cancers registered during 2000-2010. It ranked first throughout the period. Median age at diagnosis was 69 (mean $66.8{\pm}11.0$) years. The incidence rate of all male lung cancers in Ninawa (all ages) decreased from 26.4 per 100,000 in 2000 to 12.7 in 2010 (APC=-6.55%, p<.0001). The incidences in age groups 40-49, 50-59, 60-69 and 70+ decreased in earlier years and recently appeared (2007-2010) stable. The incidence in age group (0-39) remained stable between 2000-2010. Squamous cell carcinoma (SCC)was the most common type of lung cancer, while adenocarcinoma was relatively rare. Conclusions: With the data from Directorate of Health in Ninawa during the period 2000-2010, lung cancer is the most common cancer but generally declining. Among all age groups, the recent incidence of lung cancer remained stable. The SCC predominance suggests change in tobacco habits as an important factor in the trends observed.

• Journal of Preventive Medicine and Public Health
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• v.38 no.2
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• pp.147-153
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• 2005

Objectives: Studies on the geographical differences in mortality tend to use a census population, rather than a registration population, as the denominator of mortality rates in South Korea. However, an administratively determined registration population would be the logical denominator, as the geographical areas for death certificates (numerator) have been determined by the administratively registered residence of the deceased, rather than the actual residence at the time of death. The purpose of this study was to examine the differences in the total number of a district population, and the associated district-specific mortality indicators, when two different measures as a population denominator (census and registration) were used. Methods: Population denominators were obtained from census and registration population data, and the numbers of deaths (numerators) were calculated from raw death certificate data. Sex- and 5-year age-specific numbers for the populations and deaths were used to compute sex- and age-standardized mortality rates (by direct standardization methods) and standardized mortality ratios (by indirect standardization methods). Bland-Altman tests were used to compare district populations and district-specific mortality indicators according to the two different population denominators. Results : In 1995, 9 of 232 (3.9%) districts were not included in the 95% confidence interval (CI) of the population differences. A total of 8 (3.4%) among 234 districts had large differences between their census and registration populations in 2000, which exceeded the 95% CI of the population differences. Most districts (13 of 17) exceeding the 95% CI were rural. The results of the sex- and age-standardized mortality rates showed 15 (6.5%) and 16 (6.8%) districts in 1995 and 2000, respectively, were not included in the 95% CI of the differences in their rates. In addition, the differences in the standardized mortality ratios using the two different population denominators were significantly greater among 14 districts in 1995 and 11 districts in 2002 than the 95% CI. Geographical variations in the mortality indicators, using a registration population, were greater than when using a census population. Conclusion: The use of census population denominators may provide biased geographical mortality indicators. The geographical mortality rates when using registration population denominators are logical, but do not necessarily represent the exact mortality rate of a certain district. The removal of districts with large differences between their census and registration populations or associated mortality indicators should be considered to monitor geographical mortality rates in South Korea.

• Korea journal of population studies
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• v.23 no.1
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• pp.5-29
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• 2000

도시화 및 산업화는 가족의 애정기능 증대, 친족관계 약화, 공사영역분리, 여성의 교육수준 향상 및 취업기회 증가, 부부관계의 평등성 추구 등을 통해 이혼을 증가시키는 요인으로 알려져 왔다. 혼인·이혼신고 자료와 인구주택총조사 자료를 활용하여 1970년∼1995년 동안 발생한 한국의 성별, 연령별, 시도별, 교육수준별 이혼율을 비교하였다. 이혼수준을 측정하기 위하여 조이혼율, 일반이혼율, 연령별이혼율, 연령표준화 이혼을 전체인구와 유배우인구를 대상으로 각각 산출하였고, 각종 이혼력 지표의 특성을 논의하였다. 1970년∼1995년 동안 이혼율이 3배 증가하였으며, 1995년 현재 유배우인구 천 명당 3.2건의 이혼이 발생하였다. 동기간 동안 24세 이하 연령층의 이혼율이 가장 높았고, 전 연령층에 걸쳐 빠른 속도로 이혼율이 증가하였는데, 증년층의 이혼율 증가 속도가 가장 빨랐고, 남성보다는 여성의 상대적 이혼율 증가 정도가 더 빨랐다. 시도별 이혼율은 전연령층에 걸쳐 서울, 부산, 인천, 대전, 경기, 제주도가 높았고, 강원도와 전라북도 25∼34세 연령층의 이혼율이 높았다. 교육수준별 이혼율이 남자는 초등학교 졸업집단에서, 여자는 고등학교 졸업 집단에서 가장 높았고, 남자는 대졸 이상 집단, 여자는 무학 집단에서 가장 낮게 나타났다.

• Safety and Health at Work
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• v.14 no.4
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• pp.406-414
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• 2023

Background: This study examined age-group differences in the rate, severity, and cost of injuries among construction workers to support evidence-based worker safety and health interventions in the construction industry. Methods: Ohio workers' compensation claims for construction workers were used to estimate claim rates and costs by age group. We analyzed claims data auto-coded into five event/exposure categories: transportation incidents; slips, trips, and falls (STFs); exposure to harmful substances and environments; contact with objects and equipment (COB); overexertion and bodily reaction. American Community Survey data were used to determine the percentage of workers in each age group. Results: From 2007-2017, among 72,416 accepted injury claims for ~166,000 construction full-time equivalent (FTE) per year, nearly half were caused by COB, followed by STFs (20%) and overexertion (20%). Claim rates related to COB and exposure to harmful substances and environments were highest among those 18-24 years old, with claim rates of 313.5 and 25.9 per 10,000 FTE, respectively. STFs increased with age, with the highest claim rates for those 55-64 years old (94.2 claims per 10,000 FTE). Overexertion claim rates increased and then declined with age, with the highest claim rate for those 35-44 years old (87.3 per 10,000 FTE). While younger workers had higher injury rates, older workers had higher proportions of lost-time claims and higher costs per claim. The total cost per FTE was highest for those 45-54 years old ($1,122 per FTE). Conclusion: The variation in rates of injury types by age suggests that age-specific prevention strategies may be useful.

• Journal of Preventive Medicine and Public Health
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• v.43 no.2
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• pp.174-184
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• 2010

Objectives: This study shows the issues that should be considered when applying standardized rates using Community Health Survey(CHS) data. Methods: We analyzed 2008 CHS data. In order to obtain the reliability of standardized rates, we calculated z-score and rank correlation coefficients between direct standardized rate and indirect standardized rate for 31 major indices. Especially, we assessed the change of correlations according to population composition (age and sex), and characteristics of the index. We used Mantel-Haenszel chi-square to quantify the difference of population composition. Results: Among 31 major indices, 29 indices' z-score and rank correlation coefficients were over 0.9. However, regions with larger differences in population composition showed lower reliability. Low reliability was also observed for the indices specific to subgroups with small denominator such as 'permanent lesion from stroke', and the index with large regional variations in age-related differences such as 'obtaining health examinations'. Conclusions: Standardized rates may have low reliability, if comparison is made between areas with extremely large differences in population composition, or for indicies with large regional variations in age-related differences. Therefore, the special features of standardized rates should be considered when health state are compared among areas.