• Parasites, Hosts and Diseases
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• v.61 no.2
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• pp.198-201
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• 2023

In the past decade, experts have conducted parasitological research on archaeological specimens in Korea to collect historical parasite infection data. In these studies, parasitologists successfully described the infection pattern of each parasite species in history. However, in the first half of the 20th century, archaeoparasitological reports have been scant. In 2021, we conducted a parasitological examination of a toilet-like structure that emerged in the early 20th century. This structure was built by stacking 2 wooden barrels; and in the study samples, we found ancient Trichuris trichiura, Ascaris lumbricoides (unfertilized), and Taenia spp. eggs and therefore proposed a higher possibility that the barrels could have been used as a toilet at the time. To understand how the antihelminthic campaign since the 1960s helped reduce parasite infection rates in Korea, more research should focus on early-20th-century toilet ruins.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.12
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• pp.597-603
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• 2001

In the mathematical model for the transmission dynamics of HIV infection described in previous papers, the population under consideration is assumed to be homogeneous community of homosexual males for which the parameter x represents the constant rate at which individual members of the population acquire new sexual partners. This is a gross oversimplification since it is well known that individuals vary widely in their levels of sexual activity and in this papers the heterogeneous model is modified to allow for this variation. The pattern on the epidemic character of HIV, the causative agent of AIDS, was analysed by heterogeneous-mixing model. The computer simulation was performed using real date.

• Journal of Chest Surgery
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• v.4 no.2
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• pp.95-100
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• 1971

The incidence of empyema has been drastically reduced with the advent of antimicrobial drugs,however,there is still complicated and difficult problems of management of empyema remaining. During the period of December, 1958 to December, 1962, 90 patients nf empyema thoracis were managed in the Department of Thoracic Surgery of the National Medical Center, and this series deals with the incidence,etiologic consideration, bacteriology and management of empyema with its result. 1] Male predominates with the ratio of 3.1: 1, and peak age incidence lies in 3rd decade. 2] Most common etiologic factor is bronchorespiratory infection among which tuberculosis remains highest incidence. 3] 56.7% of patients shows positive result of bacteriologic study and about half of positive culture series shows mixed infection or changing pattern of bacteriological strains during serial examinations. 4] Complete cure is obtained in 84.4% of patients with 5 deaths.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8041-8045
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• 2016

Cervical cancer is one of the most common cancers in women worldwide. During their life time the vast majority of women become infected with human papillomavirus (HPV), but interestingly only a small portion develop cervical cancer and in the remainder infection regresses to a normal healthy state. Beyond HPV status, associated molecular characterization of disease has to be established. However, initial work suggests the existence of several different molecular classes, based on the biological features of differentially expressed genes in each subtype. This suggests that additional risk factors play an important role in the outcome of infection. Host genomic factors play an important role in the outcome of such complex or multifactor diseases such as cervical cancer and are also known to regulate the rate of disease progression. The aim of this review was to compile advances in the field of host genomics of HPV positive and negative cervical cancer and their association with clinical response.

• Journal of Plant Biology
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• v.36 no.3
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• pp.225-231
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• 1993

Transformed hairy roots of Scopolia parviflora, producing tropane alkaloids and native to Korea, were obtained following infection of rhizome segments with Agrobacterium rhizogenes A4. Each root tip induced from inoculum sites excised and cultured in MS agar or liquid medium. About seventy of hairy root clones were established. Among them, several fast growing hairy root clones were examined for alkaliod content. Two dimensional TLC analysis showed that the tropane alkaloid pattern of hairy root was more complicated than that in the rhizome of mother plant. On the other hand, some hairy root clones did not produce scopolamine and hyoscyamine. In HPLC analysis, some hairy root clones yield higher levels of scopolamine and hyoscyamine than those of mother plant rhizome which used for infection. Scopolamine and hyoscyamine were identified by comparison of their retention times and of their spectra data with those of authentic compounds.

• Journal of fish pathology
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• v.11 no.1
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• pp.23-27
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• 1998

This research was carried out to know the trend in annual occurrence of bacterial disease. The diseased fish were collected from 147 flounder farms of Cheju Island from January, 1991 to December, 1997. Two types of diseases, that is "simple infection" and "mixed infection", were recognized. The simple infections were Vibriosis, Edwardsiellosis Streptococcal infection and Columnaris disease. The mixed infections were caused by a pair of pathogens mentioned above. During the whole period of this study, the highest number of annual occurrence of simple infection was 243 (26.8% of the total) in 1997 and the lowest one was 82 (9.1 %) in 1991. Monthly occurrence of simple infection was the highest number at 132 (14.6% of the total) in August and the lowest one was at 38 (4.2%) in January. Monthly occurrence of the mixed infected disease showed common pattern except November and December. The highest number of annual occurrence of the simple infected disease was 437 (48.2% of the total) in Vibriosis and the lowest one was 22 (2.4%) in Columnaris disease. The highest number of annual occurrence of the simple infected disease was 178 (53.1% of the total) in Vibriosis+Columnaris disease and the lowest one was 28 (8.4%) in Edwardsiellosis+Streptococcal infection.

• Korean Journal of Organic Agriculture
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• v.19 no.3
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• pp.343-355
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• 2011

This work was studied the effects of spore density and infection of arbuscular mycorrhizal fungi (AMF) for no-tillage organic cultivation of pepper with wintering green manure crops cultivation in greenhouse field. Spore density of arbuscular mycorrhizal fungi (AMF) in green manure crops was 189 spores/30g fresh soils in control including alive spore (82 spores). Spore density of AMF in all green manure crops was totally 196~226 spores/30g fresh soil and alive spore was 84~112 spores/30g fresh soil. Spore density of AMF in soils of Pepper crop was range of 48.0~56.7 spores/30g fresh soils after cultivation of green manure crops. Infection structure of AMF was not significantly difference in soils of green manure crops and Pepper crop after cultivation of green manure crops. Infection rate of AMF in roots of green crops was low level by 2.8% in giant chickweed, 7.4% in rye, 9.3% in hairy vetch. Infection rate of AMF in roots of barley was the highest level by 20.3%. Infection rate of AMF in roots of Pepper crop was range of 5.2~7.2% after cultivation of green manure crops Also, infection rate of AMF in roots of Pepper crop was 8.1% after the harvest of barley. Infection structure of AMF in barley very well consisted of network with internal hyphae, while hairy vetch and rye tended to no network. There was not a significant relationship between spore density in soils and infection rate of AMF in rhizosphere of Pepper.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.284-290
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• 2012

Innate immune cells sense and respond to the cytoplasmic infection of bacterial pathogens through NLRP3, NLRC4 or AIM2 inflammasome depending on the unique molecular pattern of invading pathogens. The infection of flagellin- or type III secretion system (T3SS)-containing Gram-negative bacteria such as Salmonella enterica serovar Typhimurium (S. typhimurium) or Pseudomonas aeruginosa (P. aeruginosa) triggers NLRC4-dependent caspase-1 activation leading to the secretion of proinflammatory cytokines such as interleukin-1-beta (IL-$1{\beta}$) and IL-18. Previous studies have shown that apoptosis-associated speck-like protein containing a CARD (ASC) is also required for Salmonella-induced caspase-1 activation, but it is still unclear how ASC contributes to the activation of NLRC4 inflammasome in response to S. typhimurium infection. In this study, we demonstrate that S. typhimurium triggers the formation of ASC oligomer in a potassium depletion-independent manner as determined by in vitro crosslinking and in situ fluorescence imaging. Remarkably, inhibition of potassium efflux failed to block Salmonella-promoted caspase-1 activation and macrophage cell death. These results collectively suggest that ASC is substantially oligomerized to facilitate the activation of caspase-1 in response to S. typhimurium infection. Contrary to NLRP3 inflammasome, intracellular potassium depletion is not critical for NLRC4 inflammasome signaling by S. typhimurium.

• ALGAE
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• v.24 no.4
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• pp.249-256
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• 2009

The occurrence of Laminarionema elsbetiae (Ectocarpaceae, Phaeophyceae), as epi-endophyte of Rhodymenia pseudopalmata (Rhodymeniales, Rhodophyta), described from Santa Isabel, Rawson, Argentina. L. elsbetiae grows in the host tissues forming epi-endophytic relationship in the epidermal, cortical and medullar layers. Epiphytic thalli of L. elsbetiae were unbranched filaments emerging from hostis surface. Reproductive structures of L. elsbetiae on the host were absent. On the contrary, free cultured individuals formed different reproductive structures. Macrozoosporangia containing a single large motile zoospore originated from vegetative cells, they were conical to cylindrical in shape, 30-50 ${\mu}m$ in length and 18-20 ${\mu}m$ in wide. Uniseriate plurilocular zoosporangia were cylindrical shape, 40 ${\mu}m$ in length and 10-13 ${\mu}m$ in wide. Sexual fusion was not seen. In mixed cultures of L. elsbetiae with R. pseudopalmata fronds, L. elsbetiae infected the host, grew as in natural host and, formed macrosporangia between host subcortical cells. Gametophytes of L. elsbetiae were filaments with diffuse growth, branched with a branch pattern alternate or opposite. Gametangia were plurilocular, uni or biseriate and lateral. When mature they contained 2 to 6 isogametes. The presence L. elsbetiae on R. pseudopalmata could be defined as an epi-endophytic relationship. The percentage of infection of R. pseudopalmata thalli by L. elsbetiae was 34%.A25% of the infected thalli presented a low, non-symptomatic level infection, whereas a 62% and a 13% of them exhibited respectively moderate and high indexes of infection.

• Journal of Preventive Medicine and Public Health
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• v.45 no.3
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• pp.164-173
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• 2012

Objectives: Over the past several years, the incidence of hepatitis A infection has been increasing rapidly in the young-adult population in Korea. We examined the effects of area-level socioeconomic status and environmental hygiene on the incidence of hepatitis A. Methods: This study is based on the registered national population of Korea and the national health insurance data from 2004 to 2008. A total of 73 459 individuals were confirmed to have had hepatitis A. The standardized incidences of hepatitis A in 232 districts adjusted for sex and age of people were calculated for each year, and the rate ratios of the incidence rates were estimated according to area-level socioeconomic status and environmental hygiene using multiple Poisson regression models. Results: The incidence rates of hepatitis A infection were 15.6 (per 100 000) in 2004, 19.0 (per 100 000) in 2005, 27.2 (per 100 000) in 2006, 25.1 (per 100 000) in 2007, and 61.7 (per 100 000) in 2008. The analysis of the area-level effects showed that residential areas of the less deprived than other regions, areas with higher levels of education, and heavily populated areas were significantly associated with increased risk. Conclusions: There is a very strong possibility that both area-level socioeconomic status and environmental hygiene play a role in increasing the risk of hepatitis A infection in Korea. Therefore, to reduce hepatitis A infection, we need a nationwide strategy that considers these area-level characteristics.