• 제목/요약/키워드: Disease Suppression

검색결과 442건 처리시간 0.028초

Suppression of Melanose Caused by Diaporthe citri on Citrus Leaves Pretreated with Bio-sulfur

  • Shin, Yong Ho;Ko, Eun Ju;Kim, Su Jeong;Hyun, He Nam;Jeun, Yong Chull
    • The Plant Pathology Journal
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    • 제35권5호
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    • pp.417-424
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    • 2019
  • Melanose, caused by Diaporthe citri, is one of severe diseases in citrus, a major economic resource in Jeju island. To reduce the usage amount of organic synthetic fungicide, bio-sulfur was tested as an alternative chemical to control citrus melanose in the present study. Direct antifungal activity of bio-sulfur against D. citri was determined through in vitro experiment using artificial nutrient media. Disease severity of melanose on bio-sulfur pretreated citrus leaves was lower than that on untreated ones. To illustrate the mechanism of disease suppression by bio-sulfur, infection structures were observed with a fluorescent microscope and a scanning electron microscope. In fluorescent microscopic observation, most conidia rarely germinated. In addition, hyphal growth on leaves pretreated with bio-sulfur was inhibited compared to that on untreated ones. In scanning electron microscope images of bio-sulfur pretreated leaves, surfaces of most conidia were shrunk while hyphae were morphologically changed and frequently branched. Such microscopic observations were also found for leaves pretreated with a commercial fungicide Dithianon. These results suggest that bio-sulfur may be used to control citrus melanose as an environment friendly alternative to organic synthetic fungicides

모잘록병(Rhizoctonia solani)의 억제에 있어서 Chromobacterium violaceum이 생산하는 Chitinase의 역할 (Role of Chitinase Produced by Chromobacterium violaceum in the Suppression of Rhizoctonia Damping-off)

  • 박서기;이효연;김기청
    • 한국식물병리학회지
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    • 제11권4호
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    • pp.304-311
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    • 1995
  • To determine whether chitinolytic enzymes from Chromobacterium violaceum C-61 play an important role in the suppression of Rhizoctonia damping-off, Tn5 insertion mutants deficient in chitinolytic activity (Chi a- mutants) were selected and their chitinolytic and disease suppression were compared with those of the parental strain. Four Chi a- mutants selected from about 2,000 transconjugants did not inhibit mycelial growth of Rhizoctonia solani on nutrient agar-potato dextrose agar (BA-PDA) and their abilities to suppress Rhizoctonia damping-off were much lower than the parental strain. However, population density in the eggplant rhizosphere did not differ significantly between the parental strain and four Chi a- mutants. The crude enzyme of the parental strain inhibited growth of R. solani on NA-PDA and its chitinase activity was much higher than that of Chi a- mutants. But the N,N' -diacetylchitobiase activity between these isolates were not significantly different. The chitinase of Chi a- mutants was defective in 2 isoforms of 52- and 37-kDa among four isoforms of 54-, 52-, 50- and 37-kDa. A Tn5 element was inserted into one site of 10 kb EcoRI fragment of chromosomal DNA in three Chi- mutants, C61-C1, -C2, and -C3. In C61-C4 mutant, a Tn5 element was inserted into two sites of 10 kb and 4.4 kb EcoRI fragments. These results suggest that the chitinase of C. violaceum C-61 play an important role in the suppression of Rhizoctonia damping-off of cucumber and eggplant.

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뿌리혹선충 유전자의 RNA 간섭 억제에 의한 선충저항성 식물 개발 및 선충방제의 최근 연구 동향 (Recent Studies on Development of Transgenic Plants Induced Root-Knot Nematode Resistance by RNA Interference Suppression of Nematode Genes and Nematode Prevention)

  • 한범수
    • 식물병연구
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    • 제16권1호
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    • pp.10-20
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    • 2010
  • Root-knot nematodes cause billions of dollars in crop losses annually have a broad range of host over 2,000 species of plants. These nematodes are known as obligate, sedentary endo-parasites in a plant host to feed upon to complete their life cycle. To prevent the plant parasitic nematode, methyl bromide was widely applied as a soil fumigant. Other strategies to prevent or control nematodes involve RNAi-mediated suppression, R gene transformation, natural products or chemical treatments, the expression of peptide or proteins in susceptible plants, and others. Over the last decade, the entry in GenBank for Meloidogyne reveals 73,340 ESTs and recently two complete Meloidogyne spp. genomes sequences have simultaneously been presented by two groups. Recent works have demonstrated the effect of RNAi suppression to nematode target genes. These results will provide novel members of genes as a foundation for studies focused on understanding the function of M. incognita nematode genes as well as for the development of novel target genes for parasite control. Thus the successful development of biotechnology-derived plants with nematode resistance will result in large yield benefits for producers as well as environmental benefits and will accelerate the research related to pathogensresistant crops.

Identification of Differentially Expressed Genes by Exposure of Methylmercury in Neuroblastoma Cell Line Using Suppression Subtractive Hybridization (SSH)

  • Kim, Youn-Jung;Ryu, Jae-Chun
    • Molecular & Cellular Toxicology
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    • 제2권1호
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    • pp.60-66
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    • 2006
  • Methylmercury (MeHg), one of the heavy metal compounds, can cause severe damage to the central nervous system in humans. Many reports have shown that MeHg is poisonous to human body through contaminated foods and has released into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established so far. This study, using of suppression subtractive hybridization (SSH) method, was peformed to identify differentially expressed genes by MeHg in SH-SY5Y human neuroblastoma cell line. We prepared to total RNA from SH-SY5Y cells treated with solvent (DMSO) and $6.25\;{\mu}M\;(IC_{50})$ MeHg and performed forward and reverse SSH. Differentially expressed cDNA clones were screened by dot blot, sequenced and confirmed that individual clones indeed represent differentially expressed genes with real time RT-PCR. These sequences were identified by BLAST homology search to known genes or expressed sequence tags (ESTs). Analysis of these sequences may provide an insight into the biological effects of MeHg in the pathogenesis of neurodegenerative disease and a possibility to develop more efficient and exact monitoring system of heavy metals as ubiquitous environmental pollutants.

Adzuki bean (Vigna angularis) extract reduces amyloid-β aggregation and delays cognitive impairment in Drosophila models of Alzheimer's disease

  • Miyazaki, Honami;Okamoto, Yoko;Motoi, Aya;Watanabe, Takafumi;Katayama, Shigeru;Kawahara, Sei-ichi;Makabe, Hidefumi;Fujii, Hiroshi;Yonekura, Shinichi
    • Nutrition Research and Practice
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    • 제13권1호
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    • pp.64-69
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    • 2019
  • BACKGROUND/OBJECTIVES: Alzheimer's disease is a neurodegenerative disease that induces symptoms such as a decrease in motor function and cognitive impairment. Increases in the aggregation and deposition of amyloid beta protein ($A{\beta}$) in the brain may be closely correlated with the development of Alzheimer's disease. In this study, the effects of an adzuki bean extract on the aggregation of $A{\beta}$ were examined; moreover, the anti-Alzheimer's activity of the adzuki extract was examined. MATERIALS/METHODS: First, we undertook thioflavin T (ThT) fluorescence analysis and transmission electron microscopy (TEM) to evaluate the effect of an adzuki bean extract on $A{\beta}_{42}$ aggregation. To evaluate the effects of the adzuki extract on the symptoms of Alzheimer's disease in vivo, $A{\beta}_{42}$-overexpressing Drosophila were used. In these flies, overexpression of $A{\beta}_{42}$ induced the formation of $A{\beta}_{42}$ aggregates in the brain, decreased motor function, and resulted in cognitive impairment. RESULTS: Based on the results obtained by ThT fluorescence assays and TEM, the adzuki bean extract inhibited the formation of $A{\beta}_{42}$ aggregates in a concentration-dependent manner. When $A{\beta}_{42}$-overexpressing flies were fed regular medium containing adzuki extract, the $A{\beta}_{42}$ level in the brain was significantly lower than that in the group fed regular medium only. Furthermore, suppression of the decrease in motor function, suppression of cognitive impairment, and improvement in lifespan were observed in $A{\beta}_{42}$-overexpressing flies fed regular medium with adzuki extract. CONCLUSIONS: The results reveal the delaying effects of an adzuki bean extract on the progression of Alzheimer's disease and provide useful information for identifying novel prevention treatments for Alzheimer's disease.

Pituitary Pars Intermedia Dysfunction with Laminitis in a Horse

  • Lee, Eun-bee;Chun, Yong-woo;Park, Kyung-won;Kang, Tae-young;Seo, Jong-pil
    • 한국임상수의학회지
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    • 제38권1호
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    • pp.41-44
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    • 2021
  • Pituitary pars intermedia dysfunction (PPID), often referred to as equine Cushing's disease, is a common endocrine disorder often diagnosed in older horses. A 13-year-old 460 kg Warmblood gelding showed clinical signs suggestive of PPID, including hypertrichosis, fat redistribution, polyuria and polydipsia (PU/PD), and weight loss. Physical examination, complete blood cell count, and serum chemistry results were normal. However, dexamethasone suppression and plasma adrenocorticotropic hormone (ACTH) level tests confirmed PPID. Three months after the confirmed diagnosis, the horse was referred again with symptoms of laminitis. Radiography and venography were performed to evaluate the laminitis severity level. However, the foot condition continued to worsen, and the horse was eventually euthanized. The purpose of this case report is to describe clinical signs and diagnosis of PPID with laminitis.

Suppression of IL-8 production by 18-beta-Glycyrrhetinic acid is mediated by inhibition of MAPKs and NF-kappaB

  • Choi, Yeon-A;Kang, Ok-Hwa;Kim, Jin-A;Tae, Jin;Kim, Hyun-Mi;Choi, Suck-Chei;Lee, Young-Mi
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.80.1-80.1
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    • 2003
  • Intestinal epithelial cells can produce cytokines and chemokines that play an important role in the mucosal immune response. Regulation of this production is important to prevent inflammatory tissue damage. Glycyrrhiza glabra has been shown to inhibit inflammation. The aim of this study was to examine the inhibitory effect of 18- beta-glycyrrhetinic acid, a triterpenoid saponin of Glycyrrhiza glabra, on IL-S production via mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-kB) in TNF-alpha-stimulated human colon epithelial cells. (omitted)

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비병원성균주 전처리에 의한 담배세균성마름병균(Pseudomonas solanacearum)의 식물체내 침입 및 증식억제 (Inhibition Effect of Avirulent Pseudomonas solanacearum on the Multiplication of Virulent Isolate in Tobacco Plant)

  • 이영근;김정화;박원목
    • 한국식물병리학회지
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    • 제2권2호
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    • pp.114-120
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    • 1986
  • BY4품종의 담배를 포장에 이식하면서 이식 하루전과 40일 후에 비병원성 Pseudomonas solanacearum의 현탁액을 담배근권토양에 관주한 결과 7월 상순까지 세균성마름병 발생 속도가 지연되었으나 그 후에는 방제효과가 급속히 감소되었다. 그 결과 잎담배의 $35\%$ 증수 및 kg당 대금으로 $10\%$의 품질상승 효과를 얻을 수 있었다. 비병원성균주처리에 의한 근권상양내 병원균의 밀도증가억제는 인정되지 않았다. $^{32}P$로 표식된 비병원성균주의 담배뿌리를 통한 침입 및 식물체내 이동이 확인되었으며 비병원성균주에 전접종된 담배에 대하여 병원성균주의 침입 및 식물체내 증식이 억제되었다. 이러한 병원성균주의 식물체내 침입 및 증식억제 현상이 병진전 억제와 관련이 있는 것으로 생각되었다.

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석회질소에 의한 배추뿌리혹병 방제효과 (Effect of Calcium Cyanamide on Control of Clubroot of Chinese Cabbage Caused by Plasmodiophora brassicae)

  • 김점순;이정태;이계준
    • 식물병연구
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    • 제12권3호
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    • pp.278-283
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    • 2006
  • 국내 배추 재배지에서 큰 문제가 되고 있는 뿌리혹병을 석회질소로 방제하는 방법을 구명하기 위하여, 고령지농업연구소의 뿌리혹병 다발포장에서 $2002{\sim}2003 $년에 걸쳐 시험을 실시하였다. 석회질소의 처리량은 배추에 대한 질소질 비료 기비량과 같은 61 kg/10a처리할 때, 33%의 발병도를 보여 대조약제인 후루설파마이드의 77%에 비해 우수한 방제 효과를 보였다. 석회질소를 배추 정식 전 5, 10, 15, 20일에 처리한 결과, 정식 5일전 처리가 48%의 발병도를 보여 후루설파마이드 분제의 67%에 비해 발병 억제 효과가 인정되었다. 석회질소와 요소비료를 이용하여 재배한 배추의 수확기 질소 흡수량은 요소가 17.8kg/10a, 석회질소가 17.6kg/10a으로 유의성이 없었다. 이와 같은 결과로 볼 때 석회질소는 질소질 비료로서 뿐만 아니라 배추뿌리혹병을 방제하기 위한 화학약제의 대용으로서 사용될 수 있을 것으로 생각된다.