• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1995년도 Proceedings of special lectures on Molecular Biological Approaches to Plant Disease National Agricultural Science and Technology Institute Suwon, Korea
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• pp.55-75
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• 1995

Induction of HMG-Co A reductase (HMGR) is essential for the biosynthesis of sesquiterpenoid phytoalexins and steroid derivatives in Solanaceous plants following wounding and pathogen infection. To better understand this complex step in stress-responsive isoprenoid synthesis, three classes of cDNAs for HMGR (hmg1, hmg2, and hmg3) were isolated from a potato tuber library. The potato cDNAs had extensive homology in open reading frames but had low homology in the 3'-untranslated regions. RNA gel blot analysis using gene-specific probes revealed that hmg1 is induced by wounding but wound induction is strongly suppressed by arachidonic acid or by inoculation with Phytophthora infestants. In contrast, hmg2 and hmg3 are slightly induced by wounding and strongly enhanced by arachidonic acid or inoculation. The induction and suppression of HMGR genes parallel the suppression of steroid and stimulation of sesquiterpenoid accumulations observed in earlier investigations. Treatment of the tuber disks with a low concentration of methyl-jasmonate doubled the wound induced accumulation of hmg1 transcripts and steroid-glycoalkaloid accumulation, but did not affect the abundance of transcripts for hmg2 or hmg3 nor induce phytoalexins. High concentration of methyl-jasmonate suppressed hmg1 mRNA and steroid-glycoalkaloid accumulation, induced hmg3 mRNA, and did not elicit phytoalexins. Lipoxygenase inhibitors suppressed the accumulation of of hmg1 transcripts and steroid-glycoalkaloids, which were restored by exogeneous methyl-jasmonate. Methyl-jasmonate applied together with arachidonic acid enhanced the elicitor induced accumulation of sesquiterpenes and sustained steroid-glycoalkaloid levels with transcript levels for the various HMGR mRNAs equal to or greater than wound-only treatment. These results domonstrate that the consequences of wound- and pathogen-responses of plants are different at the levels of gene expression and associated secondary metabolism.

• The Plant Pathology Journal
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• 제29권2호
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• pp.193-200
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• 2013

Trichoderma asperellum SKT-1 is a microbial pesticide that is very effective against various diseases. Our study was undertaken to evaluate T. asperellum SKT-1 for induction of resistance against yellow strain of Cucumber mosaic virus (CMV-Y) in Arabidopsis plants. Disease severity was rated at 2 weeks post inoculation (WPI). CMV titre in Arabidopsis leaves was determined by indirect enzyme-linked immunosorbent assay (ELISA) at 2 WPI. Our results demonstrated that among all Arabidopsis plants treated with barley grain inoculum (BGI) of SKT-1 NahG and npr1 plants showed no significant reduction in disease severity and CMV titre as compared with control plants. In contrast, disease severity and CMV titre were significantly reduced in all Arabidopsis plants treated with culture filtrate (CF) of SKT-1 as compared with control plants. RT-PCR results showed increased expression levels of SA-inducible genes, but not JA/ET-inducible genes, in leaves of BGI treated plants. Moreover, expression levels of SA- and JA/ET-inducible genes were increased in leaves of CF treated plants. In conclusion, BGI treatment induced systemic resistance against CMV through SA signaling cascade in Arabidopsis plants. While, treatment with CF of SKT-1 mediated the expression of a majority of the various pathogen related genes, which led to the increased defense mechanism against CMV infection.

• Parasites, Hosts and Diseases
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• 제46권4호
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• pp.209-216
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• 2008

A monoclonal antibody against Toxoplasma gondii of Tg556 clone (Tg556) blotted a 29 kDa protein, which was localized in the dense granules of tachyzoites and secreted into the parasitophorous vacuolar membrane (PVM) after infection to host cells. A cDNA fragment encoding the protein was obtained by screening a T. gondii cDNA expression library with Tg556, and the full-length was completed by 5'-RACE of 2,086 bp containing an open reading frame (ORF) of 669 bp. The ORF encoded a polypeptide of 222 amino acids homologous to the revised GRA3 but not to the first reported one. The polypeptide has 3 hydrophobic moieties of an N-terminal stop transfer sequence and 2 transmembrane domains (TMD) in posterior half of the sequence, a cytoplasmic localization motif after the second TMD and an endoplasmic reticulum (ER) retrival motif in the C-terminal end, which suggests GRA3 as a type III transmembrane protein. With the ORF of GRA3, yeast two-hybrid assay was performed in HeLa cDNA expression library, which resulted in the interaction of GRA3 with calcium modulating ligand (CAMLG), a type II transmembrane protein of ER. The specific binding of GRA3 and CAMLG was confirmed by glutathione S-transferase (GST) pull-down and immunoprecipitation assays. The localities of fluorescence transfectionally expressed from GRA3 and CAMLG plasmids were overlapped completely in HeLa cell cytoplasm. In immunofluorescence assay, GRA3 and CAMLG were shown to be co-localized in the PVM of host cells. Structural binding of PVM-inserted GRA3 to CAMLG of ER suggested the receptor-ligand of ER recruitment to PVM during the parasitism of T. gondii.

• 대한수의학회지
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• 제33권3호
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• pp.479-486
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• 1993

This study was attempted co develope a method for detection of Theileria sergenti infection on the basis of hybridization of parasite DNA with a probe. For construction of a T sergenti genomic library, T sergenti DNA was digested completely with Bam-HI and the fragments were ligated into the Bam-HI site of pUC-19 before transformation of Escherichia colistrain JM83. To detect clones containing the parasite's DNA sequences, a genomic DNA library of T sergenti constructed in pUC-19 was screened by cracking and Southern hybridization. Seven colonies were chosen from 29 colonies which were screened by transformation of Escherichia coli strain JM83. Seven transformants were comfirmed from seven colonies by cracking. The sizes of transformants were about 5Kb, 5.7Kb, 4.3Kb, 7.75Kb, 7.85Kb, 5.8Kb, 3.8Kb, respectively. DNA inserts, T sergenti DNA, and bovine DNA were hybridized with radio-labelled T sergenti DNA. Two($pT_1$, $pT_1$) of the seven inserts and T sergenti DNA reacted strongly but another 5 inserts and bovine DNA showed weak reation. All of the DNA inserts were not reaction, but T sergenti DNA were very weakly and bovine DNA were strongly reacted to hybridization with radio-labelled bovine DNA. Therefore, we obtained total 7 T sergenti DNA fragments in this study.

• 대한임상검사과학회지
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• 제36권2호
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• pp.245-251
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• 2004

This study was experiment on the safety of rat(Sprague-Dawley) exposed to natural herb oil(BM-solution). BM-solution was administered by inhalation to rats with the dose level of low(30 mg/8 min), middle(30 mg/4 min) and high(50 mg/4 min) in an airtight room for 4 weeks, respectively. Each groups, consisting of 5 rats, was examined for body weight changes, hematological analysis, serum biochemical analysis, organ weight, and histopathological findings, respectively. There were, dose-dependently, no changes of body weight and organ weights, no hematological anomalousness, and no other serum biochemical abnormality from the experiments. In addition, BM-solution was shown to have no specific toxicity by gross and histopathological findings. Therefore, it was concluded that BM-solution had no side effects on rats for 4 weeks.

• 한국식품위생안전성학회지
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• 제25권1호
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• pp.6-9
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• 2010

본 연구는 황련, 금은화, 그리고 백작약 혼합분말(1:1:1)의 메탄올 추출물(CLP1000)과, 이에 dioctahedral smectite를 혼합한 합제 (CLPS1000)의 살모넬라에 대한 항균효과를 평가하기 위해 수행되었다. CLP1000와 CLPS1000는, 0. 5mg/ml 농도에서 S. typhimurium에 대한 항균효과를 보이지 않았으나, 1.0 mg/ml의 농도에서는 S. typhimurium에 대한 항균활성이 관찰되었다. BALB/c 마우스를 이용한 살모넬라 감염시험에서 Smectite, CLP1000 그리고 CLPS1000을 각각 10 mg/ml 농도로 12일 동안 투여한 결과, 사망률이 각각 90%, 90% 그리고 70%을 보여, CLPS1000이 마우스 살모넬라증에 강력한 효과를 갖고 있는 것으로 나타났다.

• Journal of Gastric Cancer
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• 제10권4호
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• pp.241-246
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• 2010

Purpose: Laparoscopy-assisted gastrectomy (LAG) has become a technically feasible and safe procedure for early gastric cancer treatment. LAG is being increasingly performed in many centers; however, there have been few reports regarding LAG at low-volume centers. The aim of this study was to report our early experience with LAG in patients with gastric cancer at a low-volume center. Materials and Methods: The clinicopathologic data and surgical outcomes of 39 patients who underwent LAG for gastric cancer between April 2007 and March 2010 were retrospectively reviewed. Results: The mean age was 68.3 years. Thirty-one patients had medical co-morbidities. The mean patient ASA score was 2.0. Among the 39 patients, 4 patients underwent total gastrectomy and 35 patients underwent distal gastrectomy. The mean blood loss was 145.4 ml and the mean operative time was 259.4 minutes. The mean time-to-first flatus, first oral intake, and the postoperative hospital stay was 2.8, 3.1, and 9.3 days, respectively. The 30-day mortality rate was 0%. Postoperative complications developed in 9 patients, as follows: anastomotic leakage, 1; wound infection, 1; gastric stasis, 2; postoperative ileus, 1; pneumonia, 1; cerebral infarction, 1; chronic renal failure, 1; and postoperative psychosis, 1. Conclusions: LAG is technically feasible and can be performed safely at a low-volume center, but an experienced surgical team and careful patient selection are necessary. Furthermore, for early mastery of the learning curve for LAG, surgeons need education and training in addition to an accumulation of cases.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 추계학술대회 및 정기총회
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• pp.26-26
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• 2015

Phytophthora infestans is the causal agent of potato and tomato late blight, one of the most devastating plant diseases. P. infestans secretes effector proteins that are both modulators and targets of host plant immunity. Among these are the so-called RXLR effectors that function inside plant cells and are characterized by a conserved motif following the N-terminal signal peptide. In contrast, the effector activity is encoded by the C terminal region that follows the RXLR domain. Recently, I performed in planta functional profiling of different RXLR effector alleles. These genes were amplified from a variety of P. infestans isolates and cloned into a Potato virus X (PVX) vector for transient in planta expression. I assayed for R-gene specific induction of hypersensitive cell death. The findings included the discovery of new effector with avirulence activity towards the Solanum bulbocastanum Rpi-blb2 resistance gene. The Rpi-blb2 encodes a protein with a putative CC-NBS-LRR (a coiled-coil-nucleotide binding site and leucine-rich repeat) motif that confers Phytophthora late blight disease resistance. We examined the components required for Rpi-blb2-mediated resistance to P. infestans in Nicotiana benthamiana. Virus-induced gene silencing was used to repress candidate genes in N. benthamiana and to assay against P. infestans infections. NbSGT1 was required for disease resistance to P. infestans and hypersensitive responses (HRs) triggered by co-expression of AVRblb2 and Rpi-blb2 in N. benthamiana. RAR1 and HSP90 did not affect disease resistance or HRs in Rpi-blb2-transgenic plants. To elucidate the role of salicylic acid (SA) in Rpi-blb2-mediated resistance, we analyzed the response of NahG-transgenic plants following P. infestans infection. The increased susceptibility of Rpi-blb2-transgenic plants in the NahG background correlated with reduced SA and SA glucoside levels. Furthermore, Rpi-blb2-mediated HR cell death was associated with $H_2O_2$, but not SA, accumulation. SA affects basal defense and Rpi-blb2-mediated resistance against P. infestans. These findings provide evidence about the roles of SGT1 and SA signaling in Rpi-blb2-mediated resistance against P. infestans.

• 대한수의학회지
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• 제38권1호
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• pp.71-76
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• 1998

The effects of chitosan on mastitis in lactating holstein cows were evaluated. Fifty six cows with intramammary infection(IMI) from nine farms were selected and the cows were fed with diets which contained 15~20g chitosan per day for 5~7 days. The milk samples were obtained from cows at 7 days and 14 days after administration to determine effect of the curing of mastitis and the reduction of somatic cell counts(SCC). The average value of SCC levels in quarter milk from the cows administrated with chitosan significantly decreased up to 31.8% and 47.7% at 7 and 14 days, respectively(P<0.05). The cure rates of chitosan for Stapylococcus aureus, coagulase-negative Staphylococci, Streptococci spp, other gram positive bacteria and coliforms were 30.4, 42.8, 33.3, 66.6 and 54.5 % respectively. Twenty three out of 64 cases were cured by feeding with chitosan. The results showed that administration of chitosan could reduce SCC in milk and improve cure rates of bovine mastitis caused by microorganisms. The further studies will be pursued to study on the mechanism of chitosan in the immune responses of cows with mastitis.

• 대한수의학회지
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• 제40권2호
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• pp.311-323
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• 2000

Immunosuppressive effects of reticuloendotheliosis virus (REV) infection in chickens were investigated. Primary antibody responses to Newcastle disease virus (strain B1) and sheep red blood cells were significantly low in chickens inoculated with the local isolate 89-74 of REV compared to those of uninfected chickens. In chickens infected with REV strain T or 89-74, blastogenesis of spleen cells and peripheral blood lymphocytes (PBL) to concanavalin A (Con A) was severely suppressed. When specific pathogen free (SPF) chickens were inoculated with the isolate, the suppressive effect was observed up to 7 weeks of age while, in the contact infected chickens, the suppression was absent. Similar suppressive effects were observed in chickens inoculated with REV strain T at 2, 3 and 4 weeks of age. When spleen cells or PBL from uninfected chickens were co-cultured with spleen cells or PBL from chickens infected with REV at 1 day-old or 2 week-old, the blastogenesis of the normal cells was suppressed. The suppressive effect of PBL from REV-infected chickens on normal lymphocytes was abrogated by the treatment with trypsin. However the suppressive activity of the REV-infected PBL was not influenced at removing machrophage from the cell suspension by incubation in plastic petri dishes. In addition to the immunosuppression, chickens infected with the REV isolate showed abnormal feather development (nakanuke), anemia, paralysis and retarded growth. Three out of 11 chickens inoculated with the isolate at day-old died between 6 and 9 weeks of age by bacterial infections.