• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.92.1-92
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• 2003

In order to develop an effective spray program for control of apple white rot with reduced use of fungicides, the control efficacy of several fungicides that has been intensively used for control of the disease was assessed. They were sprayed on the same tree with 15 day interval from late May to early August. Just prior to and after each spray, 100 fruits were bagged with two layered fruit bag to limit the chemical application in only one time, and the disease incidence and latent infection frequency on the bagged apples were examined. Some fungicides such as folpet, iminoctadine-triacetate and azoxystrobin showed a high post-infectional activity even though the former two are non- systemic. Folpet suppressed symptom development, iminoctadine-triacetate reduced infection frequency and azoxystrobin acted in both ways. When those fungicides were ！！ adopted in a spray program, once in a cropping season, their post-infectional activity became much greater. This activity shown by the non-systemic fungicides was supposed to be derived from the peculiar infection process of the white rot fungus of which the pathogen is usually remain latent in the corked cells of lenticel until the apple reach mature stage.

• Journal of Yeungnam Medical Science
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• 제39권4호
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• pp.344-346
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• 2022

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread worldwide, leading the World Health Organization to declare coronavirus disease 2019 (COVID-19) a pandemic. To curb the unchecked spread of SARS-CoV-2 infection, most countries have enforced travel restrictions. However, it is debatable whether such restrictions are effective in containing infections and preventing pandemics. Rather, they may negatively impact economies and diplomatic relationships. Each government should conduct an extensive and appropriate analysis of its national economy, diplomatic status, and COVID-19 preparedness to decide whether it is best to restrict entering travelers. Even if travelers from other countries are allowed entry, extensive contact tracing is required to prevent the spread of COVID-19. In addition, governments can implement "travel bubbles," which allow the quarantine-free flow of people among countries with relatively low levels of community transmission. An accurate evaluation of the benefits and losses due to entry restrictions during the COVID-19 pandemic would be helpful in determining whether entry restrictions are an effective measure to reduce the spread of infection in future pandemics.

• 한국식물병리학회지
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• 제2권1호
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• pp.22-30
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• 1986

흰가루병에 대하여 감수성인 봄보리품종 Peruvian과 성체식물 저항성품종 Asse의 4엽기에서 흰가루병에 감염되었을 때 $^{14}CO_2$동화와 $^{14}C-$동화산물의 대사변화를 연구하였다. 건전식물에서는 Peruvian과 Asse간에 $^{14}CO_2$동화와 $^{14}C-$동화산물 대사에서 차이가 어 없었다. 감염된 엽수가 늘어남에 다라 이들 두 품종에서 $^{14}CO_2$ 동화와 동화산물의 이행량은 감소하였다. 감염정도가 같을때도 Asse보다 Peruvian에서 $^{14}CO_2$동화가 더 감소되었다. 흰가루병이 감염되지 않은 제4엽에서도 $^{14}CO_2$고장이 줄어들었고, Peruvian에서 더 줄었다. 아래 3엽이 감염되었을 때 감염되어 있지 않는 상위 제4엽에서 fructose, glucose등의 탄수화물로 $^{14}C$가 결합되는 것을 억제하였고 Asse보다 Peruvian에서 억제가 더 컸다. 감염된 제3엽에서도 탄수화물내에 $^{14}C$이 줄어들었으나 Peruvian에서 $^{14}C$로 표식된 fructose, glucose함량이 더 높았다. 모든 식물기관에 $^{14}C$-유기산합성이 촉진되었고 Asse보다 Peruvian에서 합성이 더 뚜렷하였다. 감염된 제3엽이나 건전제4엽에서 $^{14}C$이 아미노산으로 결합되는 것이 증가하였으나 엽초로 이동은 감소되었다. 이들 잎에서 어떤 $^{14}C$-아미노산은 Asse보다 Peruvian에 더 많이 축적되었다.

• The Plant Pathology Journal
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• 제16권5호
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• pp.257-263
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• 2000

Infection with rice blast fungus (Magnaporthe grisea) significantly reduced foliar net photosynthesis (A) of rice cultivars: Ilpoom, Hwasung, and Choochung in greenhouse experiments. By measuring the amount of diseased leaf area with a computer image analysis system, the relation between disease severity (DS) and net photosynthetic rate was curvilinearly correlated (r=0.679). Diseased leaves with 35% blast symptom can be predicted to have a 50% reduction of photosynthesis. The disease severity was linearly correlated (r=0.478) with total chlorophyll (chlorophyll a and chlorophyll b) per unit leaf area(TC). Light use efficiency was reduced by the fungal infection according to the light response curves. However, dark respiration (Rd) did not change after the fungal infection (p=0.526). Since the percent of reduction in photosynthesis greatly exceeded the percent of leaf area covered by blast lesions, loss of photosynthetic tissue on an area basis could not by itself account for the reduced photosynthesis. Quantitative photosynthetic reduction can be partially explained by decreasing TC, but cannot be explained by decreasing Rd. By photosynthesis (A)-internal CO$_2$ concentration (C$_i$ curve analysis, it was suggested that the fungal infection reduced ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity, ribulose-1,5-bisphosphate (RuBP) regeneration, and inorganic phosphate regeneration. Thus, the reduction of photosynthesis by blast infection was associated with decreased TC and biochemical capacity, which comprises all carbon metabolism after CO$_2$ enters through the stomata.

• 식물병연구
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• 제19권2호
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• pp.114-117
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• 2013

To facilitate their spread, plant viruses have developed several methods for dispersal including insect and seed transmission. While insect transmission requires virus stability against insect digestion, seed-transmitted viruses have to overcome barriers to entry into embryos. Bean pod mottle virus (BPMV) is transmitted through seed at levels typically below 0.1%, but co-infection with Soybean mosaic virus (SMV) enhanced the seed transmission rate of BPMV in one experiment. In contrast, the rate of SMV seed transmission was not affected by BPMV co-infection. In a second preliminary study, the rate of SMV transmission was lower in an isoline of Williams 82 that contained a null mutation for the Kunitz trypsin inhibitor gene than in Williams 82. In this preliminary study, we observed that factors such as protease inhibitor expression and dual infection may affect the frequency of seed transmission of BPMV and SMV.

• Rapid Communication in Photoscience
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• 제5권1호
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• pp.11-12
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• 2016

Schwann cells and neuronal cells from dorsal root ganglion (DRG) in embryos of rat were cultured in vitro respectively. The purified neuronal cells with anti-mitotic agents and purified Schwann cells were co-cultured and then accomplished myelination processing. Infection of Semliki forest virus into this myelinated co-culture system was performed and then accomplished demyelination. We identified myelination and demyelination processing using antibody of neuropeptide Y.

• IMMUNE NETWORK
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• 제21권1호
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• pp.2.1-2.11
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• 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes coronavirus disease 2019 (COVID-19), an ongoing pandemic disease. In the current review, we describe SARS-CoV-2-specific CD4⁺ and CD8⁺ T-cell responses in acute and convalescent COVID-19 patients. We also discuss the relationships between COVID-19 severity and SARS-CoV-2-specific T-cell responses and summarize recent reports regarding SARS-CoV-2-reactive T cells in SARS-CoV-2-unexposed individuals. These T cells may be cross-reactive cells primed by previous infection with human common-cold coronaviruses. Finally, we outline SARS-CoV-2-specific T-cell responses in the context of vaccination. A better understanding of SARS-CoV-2-specific T-cell responses is needed to develop effective vaccines and therapeutics.

• IMMUNE NETWORK
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• 제21권1호
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• pp.3.1-3.16
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• 2021

Coronavirus disease 2019 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been spreading worldwide since its outbreak in December 2019, and World Health Organization declared it as a pandemic on March 11, 2020. SARS-CoV-2 is highly contagious and is transmitted through airway epithelial cells as the first gateway. SARS-CoV-2 is detected by nasopharyngeal or oropharyngeal swab samples, and the viral load is significantly high in the upper respiratory tract. The host cellular receptors in airway epithelial cells, including angiotensin-converting enzyme 2 and transmembrane serine protease 2, have been identified by single-cell RNA sequencing or immunostaining. The expression levels of these molecules vary by type, function, and location of airway epithelial cells, such as ciliated cells, secretory cells, olfactory epithelial cells, and alveolar epithelial cells, as well as differ from host to host depending on age, sex, or comorbid diseases. Infected airway epithelial cells by SARS-CoV-2 in ex vivo experiments produce chemokines and cytokines to recruit inflammatory cells to target organs. Same as other viral infections, IFN signaling is a critical pathway for host defense. Various studies are underway to confirm the pathophysiological mechanisms of SARS-CoV-2 infection. Herein, we review cellular entry, host-viral interactions, immune responses to SARS-CoV-2 in airway epithelial cells. We also discuss therapeutic options related to epithelial immune reactions to SARS-CoV-2.

• Parasites, Hosts and Diseases
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• 제59권4호
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• pp.399-402
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• 2021

The COVID-19 pandemic continues to be a major health problem worldwide. Timely diagnosis of co-infections mimicking COVID-19, such as malaria, might be challenging particularly in non-endemic areas. We report the first case of COVID-19 and Plasmodium ovale malaria co-infection from our region aiming to highligt the importance of travel history and prophylaxis in malaria management in the context of pandemic. The galloping sound can sometimes be a harbinger of zebra besides the horse.

• 치위생과학회지
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• 제21권1호
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• pp.1-7
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• 2021

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is transmitted primarily through droplets, and dental practitioners are at risk of occupational exposure to SARS-CoV-2 infection owing to direct contact with the patient's mouth, aerosols from dental procedures, and saliva. Wearing a mask is believed to be the best method of protection against infection, and a systematic literature review was conducted on whether the dental masks used in dentistry are effective in preventing Coronavirus Infectious Disease-19 (COVID-19). Methods: We used PubMed, Google Scholar, DBpia, NDSL, and KISS databases for this study. Of the 917 documents narrowed down by the search terms "Coronavirus, COVID-19, and dental," 83 documents were collected and studied. Ultimately, 42 of these papers were selected for analysis after considering duplication from the flow chart of the literature selection process. Results: While dental masks are often used when treating patients with unknown COVID-19 status, the Ministry of Food and Drug Safety stated that the use of dental masks is insufficient in preventing cross-transmission of COVID-19; instead, it was recommended that N95 masks, which correspond to KF94 masks, should be worn daily. On the other hand, wearing a dental mask and following precautions such as hand hygiene may not pose a significantly higher risk of infection than wearing an N95 mask when treating COVID-19 patients. Conclusion: There is an ongoing discussion regarding the use of dental masks when treating dental patients, and many argue that different types of masks should be selected according to the degree of infection and the individual's respiratory condition. By considering the safety and efficacy of dental masks in preventing infection, improvements can be made in the management of COVID-19 and dental-related infections.