• Current Optics and Photonics
• /
• v.3 no.6
• /
• pp.571-576
• /
• 2019

The morphological changes of anthracnose (fungus) -infected tomato seeds have been studied to identify the infection and characterize its effect. Full-field optical coherence tomography (FF-OCT) has been utilized as a nondestructive but efficient modality for visualizing the effects of fungal infection. The cross-sectional images extracted from a stack of en face FF-OCT images showed significant changes with infection in the seed structure. First of all, the seed coat disappeared with the infection. The thickness of the seed coat of a healthy seed was measured as 28.2 ㎛, with a standard deviation of 1.2 ㎛. However, for infected seeds the gap between surface and endosperm was not appreciably observed. In addition, the measurements confirmed that the dryness of seeds did not affect the internal seed structure. The reconstructed three-dimensional (3D) image revealed that the permeability of the seed coat, which plays the vital role of protecting the seed, is also affected by the infection. These results suggest that FF-OCT has good potential for the identification of fungus-infected tomato seeds, and for many other tasks in agriculture.

• Research in Community and Public Health Nursing
• /
• v.8 no.2
• /
• pp.314-326
• /
• 1997

In Korea, the nosocomial infection control program is not well developed. This situation is created by a lack of interest from medical personnel and the medical payment system. This study identifies current problems and develops a model for nosocomial infection control. The studies of Lee & Kim(1995), Lee (1993) and SENIC project model were used to construct this model. 1. The problems of nosocomial infection control were identified as the following: dis approval by hospital authorities, lack of sources for program direction, lack of overall structure and function in the program, inadequate direct action, lack of education and training, and so on. 2. The problems are reorganized according to the 5 elements of system theory. 3. As a result, the new nosocomial infection control model was developed. The inputs of the model were the elements, resources and boundaries of nosocomial infection. With the new model, each hospital can evaluate their current programs and plan a new program for the better control of nosocomial infection.

• Journal of Microbiology and Biotechnology
• /
• v.32 no.12
• /
• pp.1515-1526
• /
• 2022

Eukaryotic chromatin is highly organized in the 3D nuclear space and dynamically regulated in response to environmental stimuli. This genomic organization is arranged in a hierarchical fashion to support various cellular functions, including transcriptional regulation of gene expression. Like other host cellular mechanisms, viral pathogens utilize and modulate host chromatin architecture and its regulatory machinery to control features of their life cycle, such as lytic versus latent status. Combined with previous research focusing on individual loci, recent global genomic studies employing conformational assays coupled with high-throughput sequencing technology have informed models for host and, in some cases, viral 3D chromosomal structure re-organization during infection and the contribution of these alterations to virus-mediated diseases. Here, we review recent discoveries and progress in host and viral chromatin structural dynamics during infection, focusing on a subset of DNA (human herpesviruses and HPV) as well as RNA (HIV, influenza virus and SARS-CoV-2) viruses. An understanding of how host and viral genomic structure affect gene expression in both contexts and ultimately viral pathogenesis can facilitate the development of novel therapeutic strategies.

• Proceedings of the Botanical Society of Korea Conference
• /
• 1999.07a
• /
• pp.41-44
• /
• 1999

Magnaporthe grisea (Hebert) Barr (anamorph: Pyricularia grisea) is a typical heterothallic Ascomycete and the causal agent of rice blast, one of the most destructive diseases on rice (Oryza sativa L.) worldwide. The interactions between cells of the pathogen and those of the host involve a complex of biological influences which can lead to blast disease. The early stages of infection process in particular may be viewed as a sequence of discrete and critical events. These include conidial attachment, gemination, and the formation of an appressorium, a dome-shaped and melanized infection structure. Disruption of this process at any point will result in failure of the pathogen to colonize host tissues. This may offer a new avenue for developing innovative crop protection strategies. To recognize and capture such opportunities, understanding the very bases of the pathogenesis at the cellular and molecular level is prerequisite. Much has been learned about environmental cues and endogenous signaling systems for the early infection-related morphogenesis in M. grisea during last several years. The study of signal transduction system in phytopathogenic filamentous fungi offers distinct advantages over traditional mammalian systems. Mammalian systems often contain multiple copies of important genes active in the same tissue under the same physiological processes. Functional redundancy, alternate gene splicing, and specilized isoforms make defining the role of any single gene difficult. Fungi and animals are closely related kingdoms [3], so inferences between these organisms are often justified. For many genes, fungi frequently possess only a single copy, thus phenotype can be attributed directly to the mutation or deletion of any particular gene of interest.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.32 no.2
• /
• pp.174-178
• /
• 2006

Brain abscess is a rare, extremely aggressive, life-threatening infection. It may occur following : infection of contiguous structure, hematogenous spread, or cranial trauma/surgery. Dental pathology and/or treatment have been linked to a small number of brain abscesses as possible source of infection. 50-year-old male patient was presented with a brain abscess caused by Streptococcus viridans. In the case presented, the significant oral findings were chronic periapical and periodontal infection due to root remnant of lower right 3rd molar. A case history and brief literature review of brain abscess related odontogenic infection was presented after successful treatment with antibiotics and craniotomy.

• The Plant Pathology Journal
• /
• v.19 no.1
• /
• pp.34-42
• /
• 2003

The ascomycete Magnaporthe grisea is a pathogen of rice blast and is known to form specialized infection structures called appressoria for successful infection into host cells. To understand the molecular mechanism underlying infection process, appressorium-related genes were identified through global approaches including EST sequencing, differential hybridization, and sup-pression subtractive hybridization. EST database was generated on >2,000 cDNA clones randomly selected from appressorium stage cDNA library. Large number of ESTs showed homology to known proteins possibly involved in infection-related cellular development (attachment, germination, appressorium formation, and colonization) of rice blast fungus. The 1051 ESTs showing significant homology to known genes were assigned to 11 functional categories. Differential hybridization and suppression subtractive hybridization were applied to identify genes showing an appressorium stage specific expression pattern. A number of genes were selected as up-regulated during appressorium formation compared with the vegetative growing stage. Clones from various cDNA libraries constructed in different developmental stages were arrayed on slide glass for further expression profiling study. functional characterization of genes identified from these global approaches may lead to a better understand-ing of the infection process of this devastating plant disease, and the development of novel ways to protect host plant.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.26 no.3
• /
• pp.7-16
• /
• 2020

Purpose: As communicable disease, COVID-19, pandemic strikes over the world, it is critically bewared that air travel possibly be a major pass way to deliver the infectious disease virus. Especially the airplane could be an unique environment to cultivate the virus spreaders. In order to keep the continuous safe airway as well as the industry, related international associations and organizations have been published the guidelines for the prevention and control the infectious disease through the all aspects of aviation. By reviewing the guidelines, focusing on the in-flight infection prevention and control, this study would not only inform a summary of the international guidelines but also provide an essential and general consideration for related research or guideline study. Methods: Guidelines of 5 major countries are reviewed, which has been seriously influenced by COVID-19 : U.S., Canada, E.U., Australia and China. The items of the guidelines are re-categorized as its similarity and structure by applicable cases. Results: The result of this study shows that each guideline seems to share a major structure and issue such as identifying sick traveler, sick passenger care, and cleaning even though that of China has a different since it used to consider the flight conditions based on 3 levels of infection risk. For sick passenger care, the guidelines includes crew safety, service level, sick passenger isolation, and cleaning. Implications: A published guideline as a public manual could be to prevent and control the in-flight infection efficiently and promptly. It also could provide a confidence of knowledge and educate for all users to prepare the in-flight emergency as well.

• The Plant Pathology Journal
• /
• v.38 no.6
• /
• pp.583-592
• /
• 2022

Root-knot nematode disease is a widespread and catastrophic disease of tobacco. However, little is known about the relationship between rhizosphere bacterial community and root-knot nematode disease. This study used 16S rRNA gene sequencing and PICRUSt to assess bacterial community structure and function changes in rhizosphere soil from Meloidogyne incognita-infected tobacco plants. We studied the rhizosphere bacterial community structure of M. incognita-infected and uninfected tobacco plants through a paired comparison design in two regions of tobacco planting area, Yuxi and Jiuxiang of Yunnan Province, southwest China. According to the findings, M. incognita infection can alter the bacterial population in the soil. Uninfested soil has more operational taxonomic unit numbers and richness than infested soil. Principal Coordinate Analysis revealed clear separations between bacterial communities from infested and uninfested soil, indicating that different infection conditions resulted in significantly different bacterial community structures in soils. Firmicutes was prevalent in infested soil, but Chloroflexi and Acidobacteria were prevalent in uninfested soil. Sphingomonas, Streptomyces, and Bradyrhizobium were the dominant bacteria genera, and their abundance were higher in infested soil. By PICRUSt analysis, some metabolism-related functions and signal transduction functions of the rhizosphere bacterial community in the M. incognita infection-tobacco plants had a higher relative abundance than those uninfected. As a result, rhizosphere soils from tobacco plants infected with M. incognita showed considerable bacterial community structure and function alterations.

• BMB Reports
• /
• v.53 no.9
• /
• pp.449-452
• /
• 2020

The inner ear is a complex and delicate structure composed of the cochlea and the vestibular system. To maintain normal auditory function, strict homeostasis of the inner ear is needed. A proper immune response against infection, thus, is crucial. Also, since excessive immune reaction can easily damage the normal architecture within the inner ear, the immune response should be fine regulated. The exact mechanism how the inner ear's immune response, specifically the innate immunity, is regulated was unknown. Recently, we reported a protein selectively localized in the inner ear during bacterial infection, named cochlin, as a possible mediator of such regulation. In this review, the immunological function of cochlin and the mechanism behind its role within inner ear immunity is summarized. Cochlin regulates innate immunity by physically entrapping pathogens within scala tympani and recruiting innate immune cells. Such mechanism enables efficient removal of pathogen while preserving the normal inner ear structure from inflammatory damage.

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