• Molecules and Cells
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• v.45 no.12
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• pp.896-910
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• 2022

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmissible and potentially fatal virus. So far, most comprehensive analyses encompassing clinical and transcriptional manifestation have concentrated on the lungs. Here, we confirmed evident signs of viral infection in the lungs and spleen of SARS-CoV-2-infected K18-hACE2 mice, which replicate the phenotype and infection symptoms in hospitalized humans. Seven days post viral detection in organs, infected mice showed decreased vital signs, leading to death. Bronchopneumonia due to infiltration of leukocytes in the lungs and reduction in the spleen lymphocyte region were observed. Transcriptome profiling implicated the meticulous regulation of distress and recovery from cytokine-mediated immunity by distinct immune cell types in a time-dependent manner. In lungs, the chemokine-driven response to viral invasion was highly elevated at 2 days post infection (dpi). In late infection, diseased lungs, post the innate immune process, showed recovery signs. The spleen established an even more immediate line of defense than the lungs, and the cytokine expression profile dropped at 7 dpi. At 5 dpi, spleen samples diverged into two distinct groups with different transcriptome profile and pathophysiology. Inhibition of consecutive host cell viral entry and massive immunoglobulin production and proteolysis inhibition seemed that one group endeavored to survive, while the other group struggled with developmental regeneration against consistent viral intrusion through the replication cycle. Our results may contribute to improved understanding of the longitudinal response to viral infection and development of potential therapeutics for hospitalized patients affected by SARS-CoV-2.

• IMMUNE NETWORK
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• v.24 no.2
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• pp.7.1-7.19
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• 2024

Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019. In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×10⁵ plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×10² PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×10² PFU-virus-infected lungs from 2 dpi, but not in 1×10⁵ PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×10⁵ PFU; however, 1×1² PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5247-5253
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• 2012

The purpose of this study was to apply in the HACCP(Hazard Analysis Critical control) system of liquefied coffee and sikhe. The establishment of Critical limit during sterilization processing was measured by sterilization temperature and sterilization time for 30 days from April 1~30, 2012, and it was conducted at P company in Jincheon (Chungcheongbuk-do), korea. As a result, microbial(coliform, bacillus cereus, Clostridium perfringens and yeast & mold) of sikhe and liquefied coffee were detected before sterilization. In contrat, all microbial was not detected to Sikhe(238mL Can, 500mL and 300mL PP, 1.8L PP) after sterilization ($15{\pm}1$, $35{\pm}1$ and $45{\pm}1$ mins at $121{\pm}1^{\circ}C$, respectively) and Liquefied coffee was not detected after sterilization($121{\pm}1^{\circ}C$, $20{\pm}1$ mins). The sterilizer condition for deciding the most temperature and time were $121{\pm}1^{\circ}C$, $20{\pm}1$ mins. In conclusion, the sterilization process would be a great alternative to prevention, decreasing and removing of harmful microorganism, such as general bacteria, coliform and pathogenic bacteria etc. Therefore, the critical limit of sterilization temperature and time for quality control and biosafety was established at $121{\pm}1^{\circ}C$, $20{\pm}1$ mins. And it suggests that HACCP plan is necessary for monitoring method, monitoring cycle, solving method, education, training and record management during sterilization processing.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.479-485
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• 2016

Living modified (LM) crops are imported each year to South Korea as food and feeds, LM canola being one of the imported crops. The cultivation of LM crops is not permitted in South Korea but the import of these crops is increasing. In this study, we surveyed the environmental risk of imported LM canola at 9 provinces, from March 2009 to June 2013. Monitoring of canola was conducted around feed factories, roadsides, harbors, farmhouses, and flower festival regions. From the total of 595 canola samples collected from 1850 monitoring sites, we identified 6 LM canola samples. The LM canola samples were subjected to protein and DNA based analysis. PCR analyses using approved 5 single event primers (T45, MS8, RT73, Rf3 and Topas 19-2) revealed that two crops were glyphosate-resistant LM canolas, and four were glufosinate-resistant LM canolas. This study suggested that environmental monitoring is a useful research tool to manage LM crops unintentionally introduced into the environment in South Korea. This result can be used as a basis for future post-management of canola crops.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4018-4024
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• 2012

The purpose of this study was to application in the HACCP(Hazard Analysis Critical control) system of fried kimchi soup. The establishment of Critical limit during sterilization processing was measured by sterilization temperature, sterilization time, sensory test, storage test and pH change in storage for 30 days (May 1~30, 2012). Before sterilization, general bacteria, coliform and thermophile bacteria were detected to be $6.00{\times}10^5\;CFU/m{\ell}$, $7.50{\times}10^2\;CFU/m{\ell}$ and $2.75{\times}10^2\;CFU/m{\ell}$, respectively. In contrast, all microbial was not detected after sterilization($90{\pm}5^{\circ}C$, $22{\pm}5$ mins). The sensory test was decided as the most delicious kimchi according to $90{\pm}5^{\circ}C$, $22{\pm}5min$. In conclusion, the sterilization process of fried kimchi soup would be a great alternative to prevention, decreasing and removing of harmful microorganism, such as general bacteria, coliform and thermoduric bacteria etc. Therefore, the critical limit of sterilization temperature and time for quality control and biosafety was established at $90{\pm}5^{\circ}C$, $22{\pm}5$ mins. And it suggested that HACCP plan was necessary for monitoring method, monitoring cycle, problem solving method, education, training and record management during sterilization processing.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.511-522
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• 2011

Flower color is one of the main target traits in the flower breeding. Recently, technological advances in genetic engineering have been successfully reported the flower colors, such as blue roses and blue carnations that are impossible to develop by traditional breeding. Accumulated knowledge-based approaches for flavonoid biosynthesis enabled to introduce novel and unique colors into flowers. These flower color modifications have been made through the regulation of flavonoid metabolic pathway - control of endogenous gene expression and introduction of foreign genes to produce novel and specific flavonoids - and the introduction of transcription factors that are known to regulate sets of genes being involving in the flavonoid biosynthetic pathway. More empirical regulation of the flavonoids metabolism requires the understanding for regulatory mechanism of intrinsic flavonoids depending on the flower crops and the very sophisticated control of flavonoid metabolic flow. In this review, we summarized successful examples of flower color modification. It might be useful to deduce the strategy for the creation of exquisite colors in flower plants.

• The Korean Journal of Pharmacology
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• v.26 no.1
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• pp.7-12
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• 1990

Cyclobuxine D is a steroidal alkaloid, which was extracted from Buxus microphylla var. koreana Nakai. In our previous studies, we clarified several pharmacological actions of cyclobuxine D: an antiinflammatory action, hypotensive and bradycardiac effects, negative inotropic effects on the several smooth muscles and cardiac muscle. The present study was undertaken to elucidate possible mechanisms by protection of myocardial tells from ischemia and reperfusion induced derangement in cardiac function and metabolism by cyclobuxine D. For this purpose, the isolated rat heart was used. Rat hearts were perfused for 60 min under ischemia conditions in the presence and absence of cyclobuxine D and verapamil, and for 30 min under reperfusion conditions. Ischemia produced a marked decline in contractile force, an increase of resting tension, an immediate release of ATP metabolites and an accumulation of calcium in the left ventricle. Cyclobuxine D (100ng/ml) ameliorated the myocardial injury produced by ischemia.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.207-218
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• 2008

The impacts of planted transgenic rice varieties on bacterial communities in paddy soils were monitored using both cultivation and molecular methods. The rice field plot consisted of eighteen subplots planted with two genetically modified (GM) rice and four non-GM rice plants in three replicates. Analysis with denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA genes revealed that the bacterial community structures were quite similar to each other in a given month, suggesting that there were no significant differences in bacterial communities between GM and non-GM rice soils. The bacterial community structures appeared to be generally stable with the seasons, as shown by a slight variation of microbial population levels and DGGE banding patterns over the year. Comparison analysis of 16S rDNA clone libraries constructed from soil bacterial DNA showed that there were no significant differences between GM and non-GM soil libraries but revealed seasonal differences of phyla distribution between August and December. The composition profile of phospholipid fatty acids (PLFA) between GM and non-GM soils also was not significantly different to each other. When soil DNAs were analyzed with PCR by using primers for the bar gene, which was introduced into GM rice, positive DNA bands were found in October and December soils. However, no bar gene sequence was detected in PCR analysis with DNAs extracted from both cultured and uncultured soil bacterial fractions. The result of this study suggested that, in spite of seasonal variations of bacterial communities and persistence of the bar gene, the bacterial communities of the experimental rice field were not significantly affected by cultivation of GM rice varieties.

• Korean Journal of Veterinary Research
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• v.57 no.2
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• pp.105-111
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• 2017

Hyaluronic acid (HA) has been investigated for biomedical and pharmaceutical applications. This study was conducted to determine the distributions of HA nanoparticles (NPs; size 350-400 nm) and larger HA polymers in mice at intervals after application. $^{177}Lutetium$ (Lu)-labeled HA-NPs or HA polymers were intravenously injected (5 mg/kg) into male ICR mice, and radioactivity levels in blood and target organs were measured from 0.25 h to 28 days post-injection. In blood, the radioactivities of HA-NPs and HA polymer peaked at 0.5 h after injection but were remarkably decreased at 2 h; subsequently, they maintained a constant level until 6 days post-injection. HA-NPs and HA polymers were observed in the liver, spleen, lung, kidney, and heart (in ascending order) but were seldom observed in other organs. After 3 days, both the HA-NP and HA polymer levels showed similar steady decreases in lung, kidney, and heart. However, in liver and spleen, the HA-NP levels tended to decrease gradually after 1 day and both were very low after 14 days, whereas the HA polymer level accumulated for 28 days. The results indicate that HA-NPs, with their faster clearance pattern, may act as a better drug delivery system than HA polymers, especially in the liver and spleen.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.1
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• pp.41-46
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• 2010

The purpose of this study is to assess the level of fungi concentration in the university laboratories in Seoul, Korea, and to investigate factors contributing to these concentrations. The samples were taken from three spots in each laboratory; the top of sink, the center of laboratory, and the front of ventilation system, i.e fume hood at the chemical laboratory and clean bench/biosafety cabinet at the microbial laboratory. Air samples were collected using the single-stage Anderson sampler (Quick Take 30) at a flow rate of 28.3 l/min for 5 min on nutrient media in Petri-dishes located on the impactor. Fifty-two air samples were collected from 19 different laboratories (13 microbiology laboratories, 6 chemistry laboratories) in the university, and concentrations of airborne fungi showed no significant difference (p>0.05) between microbiology and chemistry laboratory, and also no significant difference at three locations (sink, center, front of ventilation system) in microbiology and chemistry laboratories. Average concentrations of fungi in 19 laboratories ranged from 7 to 459 cfu/$m^3$, with an overall Geometric Mean of 52 cfu/$m^3$. Airborne fungi concentrations of 6 samples (12 %) exceeded 150 cfu/$m^3$, the guideline of WHO. The ratios of Indoor/Outdoor for airborne fungi ranged from 0.2 to 4.8 (mean = 1.6). Related factors were measured such as relative humidity, temperature, and laboratory area. Temperature and laboratory area showed no significant relations to concentrations of airborne fungi except for relative humidity in the laboratory Concentrations of fungi were significant different (p<0.01) between rainy or cloudy and sunny. However, there was no significant difference between general ventilation and nongeneral ventilation.