• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.292-292
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• 2022

Since 1992, the Rural Development Administration (RDA), Republic of Korea in collaboration with International Rice Research Institute (IRRI) has developed 6 japonica rice varieties(MS11, Japonica 1, 2, 6, 7 and Cordillera 4) that are adaptable to tropical regions. However, these varieties show moderate resistance or susceptibility to certain biotic and abiotic stress. The development of varieties with more stable forms of resistance is highly desirable, and this could be possibly achieved through rapid introgression of known biotic and abiotic resistant genes. In this study, we analyzed the allele types of major biotic stress resistant genes including Xa5, Xa13, Xa21 and Xa25 for bacterial leaf blight, Pi5, Pi40, Pish and Pita2 for blast, tsv1 for rice tungro spherical virus, and Bph6, Bph9, Bph17, Bph18 and Bph32 for brown planthopper by using gene-specific molecular markers. In addition, seed quality related genes Sdr4 for preharvest sprouting and qLG-9 for seed longevity were also analyzed. The results revealed that2h5 and Xa25 resistance alleles showed in all varieties while Pi5 resistance allele showed only in MS11. The Pish resistance allele were present in five varieties except for Japonica 1. Meanwhile, for the rest of the genes, no presence of resistance alleles found in six varieties. In conclusions, most of tropical japonica varieties are lack of the major biotic stress resistant genes and seed quality genes (Sdr4 and qLG-9). Moreover, the results indicated that rapid deployment of a few major genes in the current tropical japonica rice varieties is urgent to increase durability and spectrum of biotic stress resistance and also seed dormancy/longevity which are essential traits for tropical environments.

• Research in Plant Disease
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• v.16 no.3
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• pp.224-231
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• 2010

Xanthomonas oryzae pv. oryzae, causal agent of bacterial leaf blight (BLB) of rice, had been collected and identified using Biolog and fatty acid analysis. Epidemics of BLB had been occurred all the times at several rice cultivating areas in Korea in 1999-2004. Most X. oryzae pv. oryzae isolated in 1999 and 2002 belonged to Korean race K1, but more than 50% of the pathogen isolated in 2003 belonged to Korean race K3. Especially, most pathogens isolated in Jeonnam and Joenbuk provinces belonged to Korean race K3. Inoculation test of near isogenic lines (NIL) of rice carrying single resistance genes against BLB showed that many isolates belonging to Korean race 1 reacted differently to diverse resistant monogenic lines of rice. Southern blot analysis also showed that the bacterial pathogens belonged to the same race had different numbers of avirulence genes. This results suggested that each Korean race type may respond to many resistance genes of rice. All the K3 races isolated in Jeonnam and Joenbuk provinces were able to cause disease on Xa3 monogenic lines of rice. Since most rice cultivars cultivated in Jeonnam and Jeonbuk were carrying Xa3 resistance genes, the bacterial pathogens isolated in Jeonnam and Jeonbuk were likely to develop to adapt to Xa3 resistance gene. Together with avirulence gene patterns of the bacterial isolates and the results of disease reaction of monogenic lines of rice to them, Korean X. oryzae pv. oryzae was classified into 19 pathotypes. This newly classified pathotypes should help the breeding of new resistance rice cultivars in Korea.

• Research in Plant Disease
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• v.10 no.1
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• pp.73-77
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• 2004

The gene analysis of resistance in rice cultivars, Daeanbyeo, Hwasunchalbyeo, Daejinbyeo, Naepungbyeo, Hwajinbyeo and Surabyeo to strains of Xanthomonas oryzae pv. oryzae was studied. F$_1$ plants and F$_2$ populations from the crosses between six cultivars and near isogenic lines carrying the single bacterial blight(BB) resistance gene were analyzed using Korean and Japanese BB races. Daeanbyeo, Hwasunchalbyeo, Daejinbyeo, Naepungbyeo, Hwajinbyeo and Surabyeo are alleic with IRBB101 but are non-alleic with IRBB104 and IRBB105. The allelic tests indicated that Daeanbyeo, Hwasunchalbyeo, Daejinbyeo, Naepungbyeo, Hwajinbyeo and Surabyeo have the Xal gene for resistance.

• Korean Journal of Veterinary Service
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• v.39 no.2
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• pp.93-99
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• 2016

The anesthetic depth and cardiovascular effect of alfaxalone constant rate infusion in dogs premedicated with xylazine or acepromazine were evaluated. Ten dogs were randomly allocated into 2 groups. In group AA, dogs were premedicated with 0.02 mg/kg of intravenous acepromazine at 15 min before induction. In group XA 1.1 mg/kg of intravenous xylazine was premedicated at 5 min before induction. The anesthesia was maintained with 6 mg/kg/hr of alfaxalone after induction with 2 mg/kg alfaxalone in both groups. In both of groups, the qualities of induction were satisfactory without any adverse event, but adequate analgesia could not be provided, according to the withdrawal test. $PaO_2$ and $SaO_2$ implied a slight hypoxemia state in XA group, while those values of group AA were not significantly changed. The acepromazine and alfaxalone combination induce mild tachycardia. The bispectral index score were significantly decreased in group XA, compared with that in group AA. The premedication of xylazine before alfaxalone constant rate infusion in this study could provide adequate analgesia during 30 min, while the premedication with acepromazine could not.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.306-311
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• 2010

The multiplication and movement of Xanthomonas oryzae pv. oryzae in rice leaves of seven near-isogenic lines(NILs) derived from different genetic sources and from the susceptible cultivar Toyonishiki were examined. The bacterium populations increased rapidly in susceptible cultivar leaves of the inoculation sites but increased gradually in NIL leaves. X oryzae pv. oryzae were detected at 20cm above the leaves of the inoculated sites in IRBB 103 and Toyonishiki but were not detected in the other NILs at 25 days after inoculation. These results support that resistant genes restrict bacterial movement not multiplication.

• Molecules and Cells
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• v.26 no.1
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• pp.34-40
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• 2008

To express an increased level of recombinant Mefp1 (marine mussel adhesive protein) in soluble form, we constructed expression vectors encoding truncated OmpA signal peptide-Mefp1 fusion proteins. OmpA signal peptide (OmpASP) is the 21 residue peptide fragment of the 23 residue OmpA signal sequence cleavable by signal peptidase I. We successfully produced increased levels of soluble recombinant Mefp1 (rMefp1) with various deletions of OmpASP, and found that the increased expression was caused by the increased pI of the N-terminus of the fusion proteins (${\geq}10.55$). All the OmpA signal peptide segments of 3-21 amino acids in length had the same pI value (10.55). Our results suggest that the pI value of the truncated OmpASP ($OmpASP_{tr}$) play an important role in directional signaling for the fusion protein, but we found no evidence for the presence of a secretion enhancer in OmpASP. For practical applications, we increased the expression of soluble rMefp1 with $OmpASP_{tr}$ peptides as directional signals, and obtained rMefp1 with the native amino terminus (nN-rMefp1) using an $OmpASP_{tr}$ Xa leader sequence that contains the recognition site for Xa protease.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.64-65
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• 1998

The inheritance of resistance to bacterial blight in a Tongil-type rice cultivar 'Changseongbyeo' was studied using a Korean isolate HB9101. which belongs to race $K_1$. The resistance of Changseongbyeo to the HB9101 was controlled by a single dominant gene. This gene was allelic with Xa-1 gene and linked to Ig gene on chromosome 4 with the recombination value of 7.5%.

• Research in Plant Disease
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• v.14 no.3
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• pp.171-175
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• 2008

The influence of rice bacterial leaf blight (BLB) disease incidence on yield and quality of Nampyung, Gang-baek and Iksan493 was investigated in three areas, Gimje, Yeongam and Jangheung, frequently found BLB infested rice. The infection rate of Nampyung, susceptible to BLB disease, was higher ($23{\sim}93%$) than Gang-baek ($2{\sim}15%$) and Iksan493 ($2{\sim}6%$), have resistant gene Xa7 and xa5, respectively. BLB disease incidence was severely found in Gimj and then yield of Nampyung was reduced 65% (352 kg/10a) compared to Iksan493 (540 kg/10a) due to the decrease in the ripen grain filling, brown/rough ratio and 1,000 grain weight. There was no difference of rice yield among Nampyung, Gangbaek and Iksan493 in Yeongam and Jangheung. The occurrence time of disease in Yeongam and Jangheung was later than Gimje and BLB disease was less infected in these areas. BLB infected rice grain showed inferior grain appearance and taste index to sound grain. independent of rice with resistant gene. In Yeongam and Jangheung, Gangbaek and Iksan493 cultivated showed lower ratio of white color to belly than Nampyung. Iksan493 showed better grain appearance and lower ratio of white core to belly than Gangbaek. In protein content of rice grain, the range of Gangbaek and Iksan493 was $6.9{\sim}9.8%$, but Nampyung showed unstable ranged from undetermined to 9.0%.

• Kyungpook Mathematical Journal
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• v.64 no.1
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• pp.15-30
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• 2024

In this paper, we focus on partial isometry elements and strongly EP elements on a ring. We construct characterizing equations such that an element which is both group invertible and MP-invertible, is a partial isometry element, or is strongly EP, exactly when these equations have a solution in a given set. In particular, an element a ∈ R^# ∩ R^† is a partial isometry element if and only if the equation x = x(a^†)^*a^† has at least one solution in {a, a#, a^†, a^*, (a^#)^*, (a^†)^*}. An element a ∈ R^#∩R^† is a strongly EP element if and only if the equation (a^†)^*xa^† = xa^†a has at least one solution in {a, a^#, a^†, a^*, (a^#)^*, (a^†)^*}. These characterizations extend many well-known results.

• Journal of Gastric Cancer
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• v.22 no.1
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• pp.47-55
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• 2022

Purpose: The use of direct oral Xa inhibitors (DXaIs) to prevent venothrombotic events is increasing. However, gastrointestinal bleeding, including that related to endoscopic resection, is a concern. In this study, we evaluated bleeding and coagulation times during the perioperative period of gastric endoscopic submucosal dissection (ESD). Materials and Methods: Patients who consecutively underwent gastric ESD from August 2016 to December 2018 were analyzed. Bleeding rates were compared among the 3 groups (antiplatelet, DXaIs, and control). DXaI administration was discontinued on the day of the procedure. Prothrombin time (PT), activated partial thromboplastin time, and the ratio of inhibited thrombin generation (RITG), which was based on dilute PT, were determined before and after ESD. Results: During the study period, 265 gastric ESDs were performed in 239 patients, where 23 and 50 patients received DXaIs and antiplatelets, respectively. Delayed bleeding occurred in 17 patients (7.4%) and 21 lesions (7.1%). The bleeding rate in the DXaI group was significantly higher than that in the other groups (30.4%, P<0.01), and the adjusted odds ratio of bleeding was 5.7 (95% confidence interval, 1.4-23.7; P=0.016). In patients using DXaIs, there was a significant (P=0.046) difference in the median RITG between bleeding cases (18.6%) and non-bleeding cases (3.8%). Conclusions: A one-day cessation of DXaIs was related to a high incidence of bleeding after gastric ESD, and monitoring of residual coagulation activity at trough levels might enable the predicted risk of delayed bleeding in patients using DXaIs.