• The Korean Journal of Physiology and Pharmacology
• /
• v.5 no.2
• /
• pp.183-188
• /
• 2001

To elucidate antidiabetic effect and mechanism(s) of acarbose in a polygenic spontaneous hyperglycemic and hyperinsulinemic diabetic animal model, $KKA^y$ mice, acarbose was administered orally for 4 weeks and effects on body weight, plasma glucose and insulin levels, genetic expressions of intestinal sucrase-isomaltase (SI), sodium-glucose cotransporter (sGLT1) and glucose transporter in quadriceps muscle (GLUT4) were examined in this study. Although no differences in body weight were detected between control and acarbose-treated groups, plasma glucose level in acarbose-treated group was markedly reduced as compared to the control. In the mechanism study, acarbose downregulated the SI and SGLT1 gene expressions, and upregulated the GLUT4 mRNA and protein expressions when compared to the control group. In conclusion, the data obtained strongly implicate that acarbose can prevent the hyperglycemia in $KKA^y$ mice possibly through blocking intestinal glucose absorption by downregulations of SI and sGLT1 mRNA expressions, and upregulation of skeletal muscle GLUT4 mRNA and protein expressions.

• IMMUNE NETWORK
• /
• v.5 no.4
• /
• pp.215-220
• /
• 2005

Background: Transforming growth factor-${\beta}$ (TGF-${\beta}1$) directs class switch recombination (CSR) to IgA isotype, which is a predominant antibody in mucosal surfaces. Although IgA is preferentially committed in mucosal lymphoid tissues, it is not definitely established whether hallmarks of IgA CSR such as IgA germ-line transcripts (GLT ${\alpha}$), post-switch transcripts (PST ${\alpha}$) and circle transcripts (CT ${\alpha}$) are readily expressed in such tissues. Therefore, we compared the expression of these transcripts among mouse Peyer's patches (PP), mesenteric lymph nodes (MLN), and spleen. Methods: Levels of GLTs, PSTs and CTs were measured by RT-PCR in isolated PPs, MLNs and spleen cells. Results: GLT ${\alpha}$ and PST ${\alpha}$ were well expressed in PP and MLN cells but in spleen cells. Similar patterns were observed in the expression of GL ${\gamma}$2b and PST ${\gamma}$2b. On the other hand, these transcripts were only inducible in spleen cells upon stimulated with LPS and TGF-${\beta}1$. In addition, CT${\alpha}$ and CT${\gamma}$2b were detected in PP cells. Conclusion: PP B cells readily express IgA GLT, PST, and CT. Overall expression patterns of these transcripts were similar in MLN cells. Thus, these results suggest that microenvironment of PP and MLN influences spontaneous IgA CSR, which lacks in systemic lymphoid tissues such as spleen.

• Applied Biological Chemistry
• /
• v.45 no.4
• /
• pp.190-194
• /
• 2002

Expression of Bacillus subtilis glutamyl-tRNA synthetase (GluRS) in Escherichia coli is lethal for the host, probably because this enzyme misaminoacylates ${tRNA_l}^{Gln}$ with glutamate in vivo. In order to overexpress B. subtilis GluRS, encoded by the gltX gene, in E. coli, this gene was amplified from B. subtilis 168 chromosomal DNA using PCR method and the entire coding region was cloned into a pET11a expression vector so that it was expressed under the control or the T7 Promoter. The resulting recombinant pEBER plasmid was transformed into E. coli Novablue (DE3) bearing the T7 RNA polymerase gene for expression. After IPTG treatment, the overproduced enzyme was purified using ammonium sulfate fractionation, Source Q anion exchange chromatography, Superdex-200 gel filtration, and Mono Q anion exchange chromatography. The purified enzyme yielded 18-fold increase in specific activity over the crude cell extract and its molecular weight was approximately 55 kDa on SDS-PAGE.

• Research in Plant Disease
• /
• v.22 no.3
• /
• pp.158-167
• /
• 2016

A pathogen that causes a new disease on green pumpkin in the nursery and the field was characterized and identified. Symptoms of the disease on green pumpkin were water soaking lesions and spots with strong yellow halo on leaf, brown lesion on flower, and yellow spot on fruit. The bacterial isolates from the leaf spot were pathogenic on the 8 curcubitaceae crop plants, green pumpkin, figleaf gourd, wax gourd, young pumpkin, zucchini, cucumber, melon, and oriental melon, whereas they did not cause the disease on sweet pumpkin and watermelon. They were Gram-negative, rod shape with polar flagella, fluorescent on King's B agar and LOPAT group 1a by LOPAT test. Their Biolog substrate utilization patterns were similar to Pseudomonas syringae pv. syringae's in Biolog database. Phylogenetic trees with 16S rRNA gene sequences and multilocus sequence typing (MLST) with nucleotide sequences of 4 housekeeping genes, gapA, gltA, gyrB, rpoD and those of P. syringae complex strains in the Plant Associated and Environmental Microbes Database (PAMDB) showed that the green pumpkin isolates formed in the same clade with P. syringae pv. syringae strains. The clade in MLST tree was in the genomospecies 1 group. The phenotypic and genotypic characteristics suggested that the isolates from green pumpkin lesion were P. syringae pv. syringae.

• Language and Information
• /
• v.4 no.1
• /
• pp.43-65
• /
• 2000

Along with the flourishign development of computational linguistics, research on the meanings of individual words has started to resume. Polyusemous words are especially brought into focus since their multiple senses have placed a real challenge to linguists and computer scientists. This paper mainly concerns the following three questions with regard to the treatments of such polysemous nouns and verbs in English and Korean. Firstly, what types of information should be represented in individual lexical entries for those polysemous words\ulcorner Secondly, how different are corresponding polysemous lexical entries in both languages\ulcorner Thirdly, what does a mental lexicon look like with regard to polysemous lexical entries\ulcorner For the first and second questions, Pustejosky's (1995) Generative Lexicon Theory (hereafter GLT) will be discussed in detail: the main focus falls on developing alternative way of representing (polysemous) lexical entries. For the third question, a brief discussion is made on mapping between concepts and their lexicalizations. Furthermore, a conceptual graph around conept 'bake' is depicted in terms of Sowa(2000)

• Journal of the Korean Society for Railway
• /
• v.9 no.1 s.32
• /
• pp.57-62
• /
• 2006

Composite thin-walled members for civil engineering application are mainly produced by pultrusion technique, and they are generally made of a polymeric resin system reinforced by E-glass fibers due to economical reason. This material combination results in low elastic moduli of the composite materials and makes the design of composite members to be governed by stability limit state. Therefore the buckling behavior of composite thin-walled members was experimentally investigated in the present study. Axial compression was applied on each specimens by a hydraulic ram and knife edge fixtures were placed at both ends to simulate simple boundary condition. Axial compression, lateral displacements and twisting at the mid-height of each specimen were measured by a set of transducers during buckling test. The experimental buckling loads were compared with analytical results obtained through isotropic formulas. In the calculation of analytical results, elastic properties such as Young's modulus(E) and shear modulus(G) were replaced with EL and GLT obtained from coupon tests, respectively.

• Research in Plant Disease
• /
• v.21 no.2
• /
• pp.82-88
• /
• 2015

Acidovorax citrulli, the causal agent of bacterial fruit blotch, has caused an economically destructive damage in cucurbits cultivation fields worldwide. To consider more effective disease management, 33 A. citrulli isolates collected from various cucurbits in Korea were analysed by multi-locus phylogeny using five conserved loci(16S rRNA, adk, gltA, glyA, pilT). Two distinct groups (KCC1 and KCC2) in the population were identified on the base of group-specific genetic variation. Out of them, the predominant group was KCC2 and both groups included isolates from melon, cucumber and watermelon. Sixty-four percent of KCC1 isolates were recovered from non-watermelon hosts and seventy-two percent of KCC2 isolates from watermelon. This study presented that there was genetic differentiation among A. citrulli population in Korea. Also, these results will be applied as a very useful data in effective disease management.

• Research in Plant Disease
• /
• v.27 no.4
• /
• pp.180-186
• /
• 2021

Typical bacterial symptoms, water-soaking brown and black leaf spots with yellow halo, were observed on watermelon seedlings in nursery and field of Gyeongnam and Jeonnam provinces. Bacterial isolates from the lesion showed strong pathogenicity on watermelon and zucchini. One of them was rod-shaped with 4 polar flagella by observation of transmission electron microscopy. They belonged to LOPAT group 1. The phylogenical trees with nucleotide sequences of 16S rRNA and multi-locus sequencing typing with the 4 house-keeping genes (gapA, gltA, gyrB, and rpoD) of the isolates showed they were highly homologous to Pseudomonas syringae pv. syringae and grouped together with them, indicating that they were appeared as P. syringae genomospecies group 1. Morphological, physiological, and genetical characteristics of the isolates suggested they are P. syringae pv. syringae. We believe this is the first report that P. syringae pv. syringae caused leaf spot disease on watermelon in the Republic of Korea.

• Korean journal of applied entomology
• /
• v.55 no.2
• /
• pp.177-188
• /
• 2016

The alpha-proteobacterium Wolbachia is one of the most important intracellular symbionts of arthropods. This Gram-negative bacterium is involved in many biological processes and is currently considered as a potential tool for biological control. Wolbachia is a cytoplasmic bacterium, maternally transferred through generations, and to facilitate its success, it has evolved several strategies that manipulate its host reproductive system to increase the number of infected individuals in the host population. The variety of Wolbachia was first recognized using genes wsp, 16S rRNA, ftsZ, gltA and groEL as molecular markers while strain genotypes of Wolbachia are determined of Multilocus sequence typing (MLST) and sequence of amino acid in region, hyper variable regions (HVRs) in protein WSP. Possible uses of the bacteria and their predominant phenotypes in control programs for agricultural pests and human disease vectors have been considered. Phenotypes are known to induce cytoplasmic incompatibility (CI), parthenogenesis induction (PI), feminization (F) and male killing (MK). Finally, applications of the bacterium in control programs of agricultural and medical insect pests have been discussed.

• Parasites, Hosts and Diseases
• /
• v.56 no.4
• /
• pp.365-370
• /
• 2018

To confirm that Bartonella and Wolbachia were carried by sheep keds (Melophagus ovinus) in southern Xinjiang of China, 17 M. ovinus samples, which were collected in Aksu Prefecture, Xinjiang, were randomly selected. In this study, the Bartonella gltA and Wolbachia 16S rRNA gene were amplified through conventional PCR and the sequence of those amplified products, were analyzed. The results demonstrated that Bartonella was carried by all of the 17 sheep keds and Wolbachia was carried by 15 out of them. Bartonella was identified as B. melophagi. Three strains of Wolbachia were supergroup F and 1 strain has not been confirmed yet. It is the first report about Wolbachia supergroup F was found in sheep keds and provided the molecular evidence that B. melophagi and Wolbachia supergroup F were carried by sheep keds in Aksu Prefecture of southern Xinjiang, China. The 2 pathogens were found in sheep keds around Taklimakan Desert for the first time.