Multifunctional Crown-5-calix[4]arene-based Phase-Transfer Catalysts for Aromatic 18F-Fluorination.

Methylated bis-triethylene glycolic crown-5-calix[4]arene (M-BTC5A) as a phase-transfer catalyst showed the best performance among other analogues and even conventional Kryptofix 222 in the nucleophilic aromatic 18F-fluorination of diaryliodonium tosylate precursors owing to (i) the efficient release of reactive "naked" [18F]fluoride, (ii) the high stabilization of the precursor in the reaction, and, presumably, (iii) the ease of access between the precursor and the K18F/M-BTC5A complex facilitated by π-π interactions. [18F]Flumazenil was produced in high radiochemical yield using M-BTC5A.

A comparative study of the trends in epidemiological aspects of Lyme disease infections in Korea and Japan, 2011-2016.

Lyme disease (LD) is one of the most prevalent tick-borne emerging infections in North America, Europe, and far Eastern Asia including Korea and Japan. This study was undertaken with the aim of a comparative and quantitative analysis of the epidemiological aspects of LD infections in Korea and Japan from 2011 to 2016. The raw data analyzed in this study were obtained from the websites of the Korea Center for Disease Control and Prevention (KCDC), Korea, and the National Institute of Infectious Diseases (NIID), Japan. In total 65 cases of LD were observed with a cumulative incidence rate (CIR) of 0.22 per million population in Korea from 2011 to 2016. During the same period in Japan, there were 75 cases of LD with a CIR of 0.10 [significantly higher than that in Korea (p <0.01)]. Further, the results showed that in Korea, LD incidence was slightly higher in women than in men; but in Japan, the case was reverse, with incidence much higher in men than women. The proportion of cases differed significantly by age-specific adjusted groups within both countries (p <0.01). In both the countries, the incidence of LD was highest among those aged ≤20 yr (93.8% cases in Korea, and 94.7% cases in Japan). Cases peaked in autumn (46.7% of total cases) in Korea and in summer (60.0%) in Japan (p <0.01). The counties in rural areas had a significantly higher proportion of cases than the capital cities in both the countries (p <0.01). The study indicates that LD in Korea and Japan is an emerging zoonosis, and pose a serious risk to public health. The results underscore the continued emergency of LD and provide a basis for targeting prevention campaigns to a population with increasing incidence. Proper information, education and communication (IEC) activities can be helpful in reducing the spread of infection.

Comparative Study on the Epidemiological Trends and Aspects of Murine Typhus in Korea in the Last Decade (2006-2015).

INTRODUCTION: In this study, we undertook a retrospective analysis of the epidemiological aspects and risk factors of murine typhus (MT) in Korea in the last decade (2006-2015). MATERIALS AND METHODS: MT infections in Korea using a total of 411 cases obtained from the Diseases Web Statistical System of the Korea Center for Disease Control and Prevention. RESULTS: In a total of 411 MT infection cases, the cumulative incidence rate was 0.08/100,000 populations. Men were slightly more infected by MT as compared to women (51.3% vs. 48.7%), and a higher incidence of MT was observed in people aged over 40 years (93.4%; P < 0.01). The seasonal pattern of outbreaks revealed that most infections occurred from October to November (69.1% of the total cases) (P < 0.01). Significantly more outbreaks occurred in the southern part (53.5%) of the Korean peninsula as compared to its northern (33.3%) and central (10.7%) parts, as well as the Jeju Island (1.0%) (P < 0.01). In addition, the number of MT infections was significantly higher in rural and sea-village (87.6%) than in urban areas (12.4%; P < 0.01). CONCLUSION: In conclusion, the rapid reemergence of MT outbreaks can be minimized through health education, and a strong enforcement of control measures against rats and their ectoparasites could markedly reduce the transmission of this infection to humans in high-risk areas.

International Travel and Exotic Dengue Fever in South Korea from 2006 to 2015.

We analyzed reported dengue fever (DF) cases and DF-relevant characteristics in South Korea from 2006 to 2015. A total of 1,260 DF notifications were obtained during the study period that were presumably introduced from endemic foreign countries. The nationwide cumulative incidence rate (CIR) of DF was 0.25 per 100,000 population; CIR of DF among overseas travelers was 0.93. CIRs of overseas male and female travelers were 1.13 and 0.87, respectively. CIR of overseas travelers aged 20-39 years was the highest. More men (61.9%) were infected with the dengue virus than women (38.1%, P<0.01). Individuals aged 20-39 years were most infected than those of other ages (58.4%, P<0.01). About a third of reported DF cases occurred between June and November. Most of the imported DF cases were associated with traveling in Southeast Asia (86.1%). The incidence of DF was highly correlated with the total number of overseas travelers (Pearson correlation r=0.842, P<0.01). The number of reported patients with DF has been increasing in the last decade, and DF is associated with international travel. To prevent dengue virus infections, greater attention should be paid to individuals who are planning to travel to Southeast Asia.

Corrigendum to "Biomechanical Evaluation of a Tooth Restored with High Performance Polymer PEKK Post-Core System: A 3D Finite Element Analysis".

[This corrects the article DOI: 10.1155/2017/1373127.].

A Comparative Study of the Trends of Imported Dengue Cases in Korea and Japan 2011 - 2015.

BACKGROUND: Dengue is a mosquito-borne febrile disease that represents a major public health problem in tropical and subtropical areas. Even though Korea and Japan are not the regions where dengue is epidemic, there have been many imported cases in both countries, and in increasing numbers. A better understanding of the characteristics of the prevalence of dengue and the recent trends in these neighboring countries may provide information to promote improvement and control strategies for both. The present study investigated the epidemiological status of imported dengue cases in Korea and Japan between 2011 and 2015, and compared their characteristics. METHODS: We analyzed the annual transition of prevalence, geographic origin of dengue infection, and seasonal distribution of occurrence. The raw data on dengue cases in Korea were obtained from the Korea Center for Disease Control and Prevention infectious diseases surveillance website and Korean Statistical Information Service website. Data on dengue cases in Japan were obtained from the National Institute of Infectious Diseases, Japan's Infectious Disease Surveillance Center website. RESULTS: There were 893 reported cases in Korea and 1,054 in Japan between 2011 and 2015. Cumulative incidence per 100,000 overseas travelers from Japan did not substantially differ from that for Korea (1.22 vs. 1.16, respectively), despite Japan's population being roughly 2.5 times larger. These results suggest Koreans engage in overseas travel more than Japanese. For Korea and Japan, Southeast Asia was the region accounting for the most cases of infection (89.4% vs. 75.4%, respectively). Notably, the Philippines and Indonesia were, respectively, the leading origin countries for Korean (38.1%) and Japanese (23.3%) cases. Seasonal distribution shows August and September were the months in which the largest number of cases occurred in Korea and Japan, respectively. These differences evidently derive from characteristics of travel destinations and timing of holidays. CONCLUSION: Based on the recent increasing trend in imported dengue cases in both countries, a more rigorous information system that can effectively provide warning of dengue risk and means of prevention for travelers headed to at-risk areas is urgently needed in both countries.

Biomechanical Evaluation of a Tooth Restored with High Performance Polymer PEKK Post-Core System: A 3D Finite Element Analysis.

The aim of this study was to evaluate the biomechanical behavior and long-term safety of high performance polymer PEKK as an intraradicular dental post-core material through comparative finite element analysis (FEA) with other conventional post-core materials. A 3D FEA model of a maxillary central incisor was constructed. A cyclic loading force of 50 N was applied at an angle of 45° to the longitudinal axis of the tooth at the palatal surface of the crown. For comparison with traditionally used post-core materials, three materials (gold, fiberglass, and PEKK) were simulated to determine their post-core properties. PEKK, with a lower elastic modulus than root dentin, showed comparably high failure resistance and a more favorable stress distribution than conventional post-core material. However, the PEKK post-core system showed a higher probability of debonding and crown failure under long-term cyclic loading than the metal or fiberglass post-core systems.

A Comparative Study of the Epidemiological Aspects of Legionnaires' Disease: Outbreaks in Korea and Japan, 2010 - 2014.

BACKGROUND: In the present study, we compared the epidemiological aspects of Legionnaire' disease (LD) outbreaks in Korea and Japan by analyzing the current state from 2010 to 2014. METHODS: The following factors were analyzed: nationwide cumulative incidence rate (CIR) per 100,000 populations and case-fatality rate in percentage, epidemiological aspects (i.e., case related to gender), male to female morbidity ratio (MFMR), age, seasonality and habitat distribution of LD cases. RESULTS: In total, there were 134 cases of LD with the CIR of 0.05 per 100,000 populations in Korea from 2010 to 2014. During the same period in Japan, there were 4,840 cases of LD with a CIR of 0.76 per 100,000 populations. The CIR in Japan was significantly higher than that in Korea. However, the case-fatality rates were at similar levels (3.0% vs. 5.9%). Moreover, LD affects both sexes differently, accounting for 2.05 and 4.41 of MFMR in Korea and Japan, respectively. In both countries, the incidence mainly occurred among people aged 40 years or older, and peaked in summer (37.3% vs. 33.7% of total cases). Significant differences were observed in the incidence of LD cases between the capital city and county areas in both two countries. These differences in LD risk factors reflect the different influences of reservoir/host with natural or artificial aquatic environments. CONCLUSION: This study provides a quantitative analysis of the epidemiological aspects and risk factors of LD outbreaks in Korea and Japan. We hope this study would be helpful for providing insight on effective future strategies to reduce LD outbreaks.

Comparison of the Epidemiological Aspects of Imported Dengue Cases between Korea and Japan, 2006-2010.

To compare the epidemiological characteristics of dengue cases imported by travelers or immigration in both Korea and Japan, we determined dengue incidence and related risk factors. During 2006-2010, 367 and 589 imported dengue cases were reported in Korea and Japan, respectively. In Korea, the presumptive origins for the dengue infections were Southeast Asia (82.6%), Southern Asia (13.9%), Eastern Asia (1.1%), South America (0.3%), Central America (0.3%), Africa (0.3%), and other countries (1.6%). In Japan, the origins of the infections were Southeast Asia (69.8%), Southern Asia (20.0%), Eastern Asia (1.7%), South America (2.5%), Central America (1.2%), Africa (1.2%), Oceania (2.4%), and other countries (1.2%). In both countries, more dengue cases were reported for men than for women (p < 0.01), and those aged 20-30 years accounted for > 60% of the total cases. The frequency of imported cases in summer and autumn (∼70% of total cases) was similar in both countries. This study demonstrates that there is a similar pattern of imported dengue cases in Korea and Japan. Therefore, there is a risk of an autochthonous dengue outbreak in Korea, as indicated by the recent outbreak in Japan in 2014.

Comparative study on the epidemiological aspects of enterohemorrhagic Escherichia coli infections between Korea and Japan, 2006 to 2010.

BACKGROUND/AIMS: To compare the epidemiological aspects of enterohemorrhagic Escherichia coli (EHEC) between Korea and Japan by analyzing the current state of EHEC infection outbreaks and related risk factors. METHODS: We investigated the epidemiological aspects of EHEC infection cases between Korea and Japan from 2006 to 2010. The following factors were analyzed: national prevalence rate (PR), regional prevalence rate, epidemic aspects (i.e., Cases related to gender), male to female morbidity ratio, age, and seasonal distribution. RESULTS: In total, there were 254 cases of EHEC with an average PR of 0.11 per 100,000 populations in Korea from 2006 to 2010. During the same period in Japan, there were 20,883 cases of EHEC with an average PR of 3.26 per 100,000 populations. The PR in Japan was significantly higher than that in Korea (p < 0.01). In both countries, more females than males had EHEC infections, with the highest incidence of infections (> 50%) observed for individuals younger than 9 years. EHEC is an emerging zoonosis and may be caused by consumption of raw or undercooked meat products from ruminants. CONCLUSIONS: This study provides a quantitative analysis of the epidemiological aspects and risk factors of EHEC infections in Korea and Japan and will provide insight on effective future strategies to reduce these infections.

A Comparative Study of the Epidemiology of Human Leptospirosis in Korea and Japan between 2006 and 2012.

We undertook a comparative analysis of the epidemiology of reported human leptospirosis (HL) cases in Korea and Japan. Between 2006 and 2012, the cumulative incidence of HL in Korea was higher than that in Japan (1.26 vs. 0.14 per 100,000 population, respectively), and the total reported cases were 632 and 196, respectively. Significantly more men were infected than women in both Korea (63.0% men, P < 0.01) and Japan (87.8% men, P < 0.01). In both countries, the incidence was highest among those aged 40 years and older (60%), and peaked in autumn (78.5% cases in Korea, and 46.9% cases in Japan). However, Japan exhibited a significantly higher proportion of male cases, a younger age distribution, and less prominent seasonality. A significant difference was observed in the incidence of HL between the capital city and rural areas in Korea, but not in Japan. The differences in agricultural and forestry practices, and the efficacy or wastewater treatment infrastructure might influence the incidence level in rural areas in both countries. The differences between the 2 countries might be because of their unique geographical characteristics and variations in their levels of industrialization.

Trends in the epidemiological aspects and mortality of alcoholic liver disease in Korea in the decade between 2000 and 2009.

BACKGROUND: Alcohol consumption and related alcohol liver disease (ALD) have substantially increased in Korea during the last decade. The objective of this study was to evaluate the trends in the epidemiological aspects and mortality rate (MR) of Korea in the decade between 2000 and 2009. METHODS: The raw data analyzed in this study were obtained from the website of "the ALD" managed by Korea Center for Disease Control and Prevention (KCDC), Korea Public Health Association (KPHA), and statistics website of Statistics Korea. The data analyses were performed using Excel 2007 statistical software (Microsoft Corp., USA). RESULTS: The amount of alcohol-consumption-per-capita-per-year (ACCY) in Korea was 8.38 L in 2000 and 8.54 L in 2009. The most taken alcoholic beverage was soju, followed by beer. There were a total of 1,403 case-fatalities (CF) with an MR of 2.98 per 100,000 populations of ALD in 2000, while a total of 3,588 CF with an MR of 7.21 in 2009 (P < 0.01). The CF and MR of ALD in males were significantly higher than those in females (P < 0.01). In over 40-year-old age groups, the CF and MR were significantly increased (P < 0.01). Moreover, occupational classification revealed that the mistress/students/jobless (MSJ) were the most risky group. The comparison of overall CF and MR of ALD by six key classifications (International Classification of Diseases (ICD)) showed that alcoholic cirrhosis (229 CF and 16.3%) in 2000 tended to be increased in 2009 (2,803 CF and 78.1%), while alcoholic fibrosis and sclerosis (607 CF and 43.3%) in 2000 significantly decreased in 2009 (120 CF and 3.3%), respectively. CONCLUSION: ALD is one of the most severe diseases in Korea, as indicated by its high CF and MR in this study. As over-consumption of alcoholic beverages is relatively common in Korea, more efforts should be made toward prevention of ALD by raising awareness of the risk factors of ALD by public health education.

Epidemiology of brucellosis among cattle in Korea from 2001 to 2011.

In the present study, the outbreak patterns of bovine brucellosis in Korea from 2000 to 2011 were analyzed to understand the epidemiological evolution of this disease in the country. A total of 85,521 brucella reactor animals were identified during 14,215 outbreaks over the 12-year study period. The number of bovine brucellosis cases increased after 2003 and peaked in 2006 before decreasing thereafter. The majority of the bovine brucellosis cases were Korean native cattle, Han Woo. The numbers of human brucellosis cases and cattle outbreaks increased and decreased in the same pattern. The correlation coefficient for human and bovine cases per year was 0.96 (95% confidence interval = 0.86 ˜ 0.99; p < 10⁻³). The epidemiological characteristics of bovine brucellosis appeared to be affected by the intensity of eradication programs that mainly involved a test- and-slaughter policy. Findings from the present study were based on freely available statistics from web pages maintained by government agencies. This unlimited access to information demonstrates the usefulness of government statistics for continually monitoring the health of animal populations.

Epidemiology of hemorrhagic fever with renal syndrome in Korea, 2001-2010.

This study describes the epidemiology of hemorrhagic fever with renal syndrome (HFRS) in the past 10 yr (2001-2010) in Korea. During this period, a total of 3,953 HFRS patients and an average prevalence rate of 0.81 per 100,000 population were recorded, with a total of 40 fatal cases, corresponding to a case fatality rate of 1.01%. More HFRS cases were found in men than in women (57% vs 43%), and a higher prevalence rate of HFRS was observed in patients older than 40 yr (82.1%). The highest numbers of HFRS cases were found amongst farmers (35.6%). The majority of HFRS cases (71.3%) occurred in the last quarter of the calendar year (October to December). More HFRS cases occurred in the western part than in the eastern part of Korea (68.9% vs 31.1%). The incidence of HFRS was significantly higher (P < 0.001) in rural areas than in urban areas (80.3% vs 19.7%). HFRS still occurs commonly among men, in autumn, and in western rural area of Korea.

Retrospective analysis of epidemiological aspects of Vibrio vulnificus infections in Korea in 2001-2010.

In this study, we performed a retrospective, quantitative analysis of the epidemiological aspects and risk factors of Vibrio vulnificus infections in Korea from 2001 to 2010. In a total of 588 V. vulnificus infection cases (prevalence rate, 0.12 cases/100,000 persons), 285 were fatal (case-fatality rate [CFR], 48.5%). Males were more significantly infected by V. vulnificus than females (86.1% versus 13.9%; P < 0.01), and a higher incidence of V. vulnificus infections was observed in people aged more than 40 years (95.1%; P < 0.01). Moreover, most V. vulnificus infections occurred in the unemployed (42.0%; P < 0.01). The seasonal patterns of outbreaks revealed that most outbreaks occurred in June (early summer) throughout November (the end of autumn) (99.6%; P < 0.01), and significantly more outbreaks occurred in the southern part (65.3%) of the Korean peninsula compared with those in the northern (29.4%) and central (5.3%) parts (P < 0.01). In addition, the number of V. vulnificus infections was significantly higher in rural and coastal villages (69.9%) than in urban areas (30.1%) (P < 0.01). In conclusion, because of the rapid aggravation and high CFR of V. vulnificus infections, public health education should strongly recommend avoiding raw seafood products and limited exposure to marine water during the summer.

A retrospective study of the extensive eradication program for brucellosis outbreaks and control in Korea, 2002-2009.

This study concerns the quantitative analysis of brucellosis outbreaks and the related risk factors and control programs for both domestic cattle and human brucellosis infections in Korea between 2002 and 2009. There were a total of 77,082 infections of bovine brucellosis (BB) in domestic cattle with a prevalence rate (PR) of 13.3 per 1,000 cattle; during the same period there were 620 cases of human brucellosis (HB) with a PR of 0.16 per 100,000 persons. Moreover, the correlation coefficient of brucellosis outbreaks between cattle and humans was highly significant (r = +0.985). The attack ratio of HB cases was 8.04 per 1,000 BB cases. The distribution of brucellosis outbreaks was concentrated in the southeast region of Korea (P < 0.01). Significantly more males were infected than females (86.9% versus 13.1%), and a high incidence of HB was observed in those aged more than 40 years (86.1%). The majority of HB cases occurred primarily among rural inhabitants (92.3%) and among famers and related workers (47.9%). Finally, all of the measures that were applied in the extensive eradication program for brucellosis outbreaks and control were based principally on an intensive test-and-slaughter policy and contributed significantly to the reduction in the outbreaks of brucellosis in Korea.

Epidemiological aspects of human brucellosis and leptospirosis outbreaks in Korea.

UNLABELLED: In order to compare the epidemiological aspects of human brucellosis (HB) and human leptospirosis (HL) outbreaks in Korea, we have analyzed the current state both of the disease incidence and related risk factors. A total 651 cases of HB occurred between 2001 and 2010 in Korea, and the average incidence rate per 100,000 populations was 0.15. A total 1,153 of HL cases occurred during the same period, and its rate was 0.24. While most of the HB prevalence occurred in the whole year round, prevalence in summer was more prominent for HB (p < 0.01), while outbreaks in autumn was more frequent for HL (p < 0.01). Geographical distribution HB cases were eastern and western regions of the rural (88.6% of total) in the Korean peninsula, showing higher outbreaks than other areas, while HL occurred in easterly regions (64.5%). Significantly more males were infected in both HB (86.8%) and HL (59.5%) than those of females in both HB (13.1%) and HL (41.1%), respectively (p < 0.01). The distribution by age groups were different between HB and HL, while the outbreaks over 62.1% of the cases of HB occurred in 40- to 59-year-old age group, and that of HL was clearly showing a high incidence in the elderly age over 60-year-old (59.6%) (p < 0.01). In both diseases, elderly people especially in famers showed a very high incidence rate (57.9% of HB and 52.2% of HL), which is possible due to increased outdoor activities and a decreased number of young people in those areas. The occupational distribution of HB cases was famers, veterinarians, dairyman and others, and those of HL cases were broad. In conclusion, the difference between HB and HL risk factors reflects the different influence of host/vector, climate, and geographical and environmental characteristics in the epidemiological patterns. KEYWORDS: Human brucellosis and leptospirosis; Epidemic aspects; Risk factors.

Retrospective study of extensive vaccination programs for canine rabies control and public health in Korea.

This retrospective study of the patterns and efforts of the extensive vaccination programs for canine rabies control (EVPCRC) compared the prevalence rate (PR) of rabies under two different vaccination programs for dogs in Korea between 1962 and 2007. A total of 753 cases of rabid dogs were reported between 1962 and 2007, and there were 350 human cases reported in the same period. There were 518 cases (PR, 4.11) of rabid dogs reported from 1962 to 1979, when the low-egg-passage Flury strain vaccine was used, and a total of 342 human cases were observed over the same period. However, there were 235 rabid dogs (PR, 0.83) identified from 1980 to 2007 when the Evelyn-Rokitnicki-Abelseth strain vaccine was used, and only 8 human cases of rabies were observed during the same period. The prevalence of rabies in dogs during the two periods was significantly different (P < 0.01). Moreover, the year with the largest outbreak, 1975, contained 91 cases, and the PR value was 6.3. In 1963, for humans, there were 103 cases, and the PR value was 0.4. However, in recent years, raccoon dogs have increased as a reservoir of rabies in the mountain areas linking North Korea with South Korea near the demilitarized zone, reflecting areas with poor EVPCRC.

Epidemiological aspects of exotic malaria and dengue fever in travelers in Korea.

In order to compare the epidemiological aspects of exotic malaria (EM) and dengue fever (DF) imported by travelers in Korea, we have analyzed the current state both of the disease incidence and related risk factors. A total of 345 cases of EM occurred between 2001 and 2008 in Korea, and the average incidence rate per 100,000 population was 0.091. A total of 252 of DF cases occurred during the same period, and its rate was 0.063. While most of the EM and DF prevalence occurred in summer, prevalence in spring and winter was more prominent for EM (P < 0.05 ~ P < 0.01), while outbreaks in summer were more frequent for DF (P < 0.01). In Korea, more males were infected with EM and DF than females (P < 0.01). The remarkable difference between gender distributions in Korea is believed to reflect cultural differences in terms of work and travel. In both diseases, the manhood age bracket (20 - 39 years old) is possible due to increased oversea activities and travel. Moreover, reported EM cases in several prefectures in the regions of Asia and Africa were widely spread by the appropriate vector of mosquitoes, while the vectors of DF in the region of Asia are limited.

Comparative research on epidemiological aspects of tsutsugamushi disease (scrub typhus) between Korea and Japan.

In order to compare the epidemiological aspects of tsutsugamushi disease (scrub typhus) between Korea and Japan, we analyzed the current state of tsutsugamushi disease outbreaks and related risk factors. The average prevalence rate of tsutsugamushi disease from 2001 to 2005 in Korea was higher than that in Japan (7.2 and 0.3 per 100,000 population, respectively) (P<0.01). The seasonal distribution in Korea showed that the incidence of tsutsugamushi disease in autumn (94.5% of total cases) was higher than in Japan (38.2%) (P<0.01), while the incidences of outbreaks in other seasons were much higher in Japan (P<0.01). In Korea, more females (64.8%) were infected than males (35.2%) (P<0.01), while there was no significant difference in Japan. The remarkable difference between the gender distribution in Korea and Japan is believed to reflect cultural differences between the two countries in terms of work, dress and ornamentation. In both countries, elderly people (over 60 years old), especially in rural areas, showed a very high prevalence rate (50%), which is possibly due to increased outdoor activities and a decreased number of young people in those areas. These differences in tsutsugamushi disease risk factors reflect the different influences of vectors/hosts, climate, and geographical and cultural characteristics between the two countries.