• Title/Summary/Keyword: cell infection

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Analysis of fusogenic activity of autographa californica nuclear polyhedrosis virus (Ac NPV) gp64 envelope glycoprotein

  • Kim, Hee-Jin;Yang, Jai-Myung
    • Journal of Microbiology
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    • v.34 no.1
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    • pp.7-14
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    • 1996
  • Teh baculovirus gp64 glycoprotein is a major component of the envelope of budded virus (BV) and has been shown that it plays an essential role in the infection process, especially virus-cell membrane fusion. We have cloned Autographa californica Nuclear Polyhedrosis Virus (AcNPV) gp64 protein were examined for membrane fusion activity by using a synchtium formation assay under various conditions. The optimal conditions required for inducing membrane fusion are 1) form pH 4.0 to 4.8 2) 15 min exposure of cells to acidic pH 3) at least 1 .mu.g of gp64 cloned plasmid DNA per 3 * 10$^{6}$ cells 4) and an exposure of cells to acidic pH at 72 h post-transfection. In order to investigate the role of hydrophobicity of the gp64 glycoprotein for the membrane fusion, the two leucine residues (amino acid position at 229 and 230) within hydrophobic region I were substituted to alanine by PCR-derived site-directed mutagenisis and the membrane fusion activity of the mutant was anlaysed. The gp64 glycoprotein carrying double alamine substitution mutation showed no significant difference in fusion activity. This result suggested that minor changes in hydrophobicity at the amino acid position 229 and 230 does not affect the acid-induced membrane fusion activity of the gp64 glycoprotein.

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Cryptocaryon irritans infection in River puffer (Takifugu obscurus) cultured in sea water (해수 양식 황복의 백점충 (Cryptocaryon irritans )감염)

  • Park, Seong-U;Choe, Hyeon-Min;Yu, Jin-Ha
    • Journal of fish pathology
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    • v.17 no.2
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    • pp.99-103
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    • 2004
  • White spot disease by Cryptocaryon irritans broke out among cultured river puffer (Takifugu obscurus) cultured in sea water in Oct. 2001 and May 2004. Many white spots were easily observed on the gills with the naked eyes. The parasites attached on the gills at the base of the gill lamellae. The trophonts penetrated the interlamellar epithelium. Epithelial cell proliferation in interlamellar spaces occurred. PAS- positive mucous cells were prominent in the proliferated epithelium.

A Case of Clinical Improvement after Enzyme Replacement Therapy in Pompe Disease (효소 보충 치료로 호전을 보인 Pompe병 1례)

  • Jeon, You Hoon;Eun, Baik Lin;Lee, Dong Hwan
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.5 no.1
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    • pp.18-22
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    • 2005
  • Pompe disease is a genetic disorder caused by a deficiency of acid ${\alpha}$-glucosidase (GAA). This enzyme defect results in lysosomal glycogen accumulation in multiple tissues and cell types, with cardiac, skeletal, and smooth muscle cells the most seriously affected. Infantile-onset Pompe disease is uniformly lethal. Affected infants present in the first few months of life with hypotonia, generalized muscle weakness, and a hypertrophic cardiomyopathy, followed by death from cardiorespiratory failure or respiratory infection, usually by 1 year of age. Late-onset forms is characterized by a lack of severe cardiac involvement and a less severe short-term prognosis. Enzyme replacement therapy for Pompe disease is intended to address directly the underlying metabolic defect via intravenous infusions of recombinant human GAA to provide the missing enzyme. We experienced one case of Pompe disease in 3-years old boy that has improved his exercise ability and cardiac function after GAA enzyme replacement therapy.

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The Stress-Activated Signaling (SAS) Pathways of a Human Fungal Pathogen, Cryptococcus neoformans

  • Jung, Kwang-Woo;Bahn, Yong-Sun
    • Mycobiology
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    • v.37 no.3
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    • pp.161-170
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    • 2009
  • Cryptococcus neoformans is a basidiomycete human fungal pathogen that causes meningoencephalitis in both immunocompromised and immunocompetent individuals. The ability to sense and respond to diverse extracellular signals is essential for the pathogen to infect and cause disease in the host. Four major stress-activated signaling (SAS) pathways have been characterized in C. neoformans, including the HOG (high osmolarity glycerol response), PKC/Mpk1 MAPK (mitogen-activated protein kinase), calcium-dependent calcineurin, and RAS signaling pathways. The HOG pathway in C. neoformans not only controls responses to diverse environmental stresses, including osmotic shock, UV irradiation, oxidative stress, heavy metal stress, antifungal drugs, toxic metabolites, and high temperature, but also regulates ergosterol biosynthesis. The PKC(protein kinase C)/Mpk1 pathway in C. neoformans is involved in a variety of stress responses, including osmotic, oxidative, and nitrosative stresses and breaches of cell wall integrity. The $Ca^{2+}$/calmodulin- and Ras-signaling pathways also play critical roles in adaptation to certain environmental stresses, such as high temperature and sexual differentiation. Perturbation of the SAS pathways not only impairs the ability of C. neoformans to resist a variety of environmental stresses during host infection, but also affects production of virulence factors, such as capsule and melanin. A drug(s) capable of targeting signaling components of the SAS pathway will be effective for treatment of cryptococcosis.

Biotransformation of Glycyrrhizin by Human Intestinal Bacteria and its Relation to Biological Activities

  • Kim, Dong-Hyun;Hong, Sung-Woon;Kim, Byung-Taek;Bae, Eun-Ah;Park, Hae-Young;Han, Myung-Joo
    • Archives of Pharmacal Research
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    • v.23 no.2
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    • pp.172-173
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    • 2000
  • The relationship between the metabolites of glycyrrhizin (18$\beta$-glycyrrhetinic acid-3-O--D-glu-curonopyranosyl-($1{\rightarrow}2$)-$\beta$-D-glucuronide, CL) and their biological activities was investigated. By human intestinal microflora, CL was metabolized to 18$\beta$-glycyrrhetinic acid (GA) as a main product and to 18$\beta$-glycyrrhetinic acid-3-O-$\beta$-D-glucuronide (GAMG) as a minor product. The former reaction was catalyzed by Eubacterium L-8 and the latter was by Streptococcus LJ-22. Among GL and its metabolites, GA and GAMG had more potent in vitro anti-platelet aggregation activity than GL. GA also showed the most potent cytotoxicity against tumor cell lines and the potent inhibitory activity on rotavirus infection as well as growth of Helicobacter pylori. GAMG, the minor metabolite of GL, was the sweetest.

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Anti-Inflammatory Effects of Rice Bran Ethanol Extract in Murine Macrophage RAW 264.7 Cells (미강에탄올추출물의 RAW264.7 세포에서 항염증효과)

  • Park, Jeong-Suk;Kim, Mi-Hye
    • YAKHAK HOEJI
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    • v.55 no.6
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    • pp.456-461
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    • 2011
  • The aim of the present study is to investigate the anti-inflammatory effect of a Rice Bran Ethanol Extract (RBE). Inflammation, such as a bacterial infection in vivo metabolites, such as external stimuli or internal stimuli to the defense mechanisms of the biological tissue a variety of intracellular regulatory factors deulin inflammatory TNF-${\alpha}$, IL-$1{\beta}$, IL-6, IL-8, such as proinflammatory cytokines, prostagrandin, lysosomal enzyme, free radicals are involved in a variety of mediators. The present study was designed to determine the effect of the RBE on pro-inflammatory factors such as NO, iNOS expression and TNF-${\alpha}$, IL-$1{\beta}$, IL-6 in lipopolysaccharide (LPS) - stimulated RAW264.7 macrophages cells. The cell toxicity was determined by MTS assay. To evaluate of anti-inflammatory effect of RBE, amount of NO was measured using the NO detection kit and the iNOS expression was measured by reverse transcriptase polymerase chain reaction (RT-PCR). And proinflammatory cytokines were measured by ELISA kit. As a result, the RBE reduced NO, iNOS expression and TNF-${\alpha}$, IL-$1{\beta}$, IL-6 production without cytotoxicity. Our results suggest that the RBE may have an anti-inflammatory property through suppressing inflammatory mediator productions and appears to be useful as an anti-inflammatory material.

Comparison study of Korean and Chinese ginsengs on the regulation of lymphocyte proliferation and cytokine production (한국 홍삼과 중국 홍삼의 경구 투여가 흰쥐의 림프구 증식과 Cytokine에 미치는 영향에 대한 비교 연구)

  • Lee, Beom-Joon;Heo, Hong;Oh, Se-Choon;Lew, Jae-Hwan
    • Journal of Ginseng Research
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    • v.32 no.3
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    • pp.250-256
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    • 2008
  • Red ginseng is a medicinal herb widely used in East-Asia for a long time. Recently there have been a lot of studies about the effect of red ginseng on the immune responses. We investigated the differences between Korean red ginseng and Chinese red ginseng in the lymphocyte proliferation and cytokine production. The rats were divided into 3 groups, KRG(Korean Red Ginseng) group, CRG(Chinese Red Ginseng) group, and the Control group. Experimental groups were administered with Korean and Chinese red ginsengs for three months respectively. Then we obtained the lymphatic cells from spleen and compared the ability of KRG on the lymphocyte proliferation and the cytokine production after mitogen-stimulated culture to CRG. The proliferation of lymphocyte and level of $IL-1{\alpha}$ were significantly increased only in KRG group. There were significant increases in the level of $INF-{\gamma}$ in both KRG and CRG groups. There were no significant differences in the level of IL-2 and $TNF-{\alpha}$. These results indicate that KRG can induce infection-relevant immune responses much faster and higher than CRG. Furthermore, functional activation of CD8+ T-cell may be activated by red ginsengs.

Agrobacterium-Mediated Transformation of Flammulina velutipes with NaOH Treatment (NaOH처리에 의한 Agrobacterium이용 팽이균사체 형질전환)

  • Shin, Dong-Il;Park, Hee-Sung
    • The Korean Journal of Mycology
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    • v.39 no.3
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    • pp.235-238
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    • 2011
  • Agrobacterium harboring vector pCHBs with hygromycin phosphotransferase(hph) and hepatitis B virus surface antigen(HBsAg)gene was transformed into the mycelial culture of Flammulina velutipes. In particular, mild NaOH solution was treated to the mycelia before Agrobacterium infection step. This was purposed to generate putative surface wounds in the mycelial cell walls. The results showed that hygromycin-resistant($hyg^r$) mycelia could be obtained only from NaOH-treated mycelia but not from intact mycelia. The integration of $hyg^r$ gene in fungal genome was confirmed by PCR. In addition, a single transgene integration and heterologous protein expression in F. velutipes could be verified by Southern blot hybridization and western blot analysis, respectively. This study demonstrated an efficient tool for the Agrobacterium-mediated transformation of F. velutipes mycelia.

Pathological changes on naturally occuring necrotic enteritis in chicken (닭의 괴사성 장염에 대한 병리학적 연구)

  • Kim, Hong-jib;Kang, Mun-il;Chung, Un-ik
    • Korean Journal of Veterinary Research
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    • v.37 no.1
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    • pp.161-166
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    • 1997
  • From January of 1991 to December of 1992, 42 chickens collected from 21 poultry farms and also diagnosed as necrotic enteritis(NE) was examined clinical signs, gross and histopathological findings. Main clinical signs were characterized by decreased appetite, mild to severe depression, reductance to move, ruffled feathers, greenish to yellow-browinish diarrhea sometimes including blood. As progressed, diseased chickens showed feces mixed with necrotic debris which detached from the intestinal mucosa and mostly resulted in the death. In chronic cases, there were dirty feathers around cloaca due to diarrhea and notably retarded growth. Principle gross lesions were usually confined to the jejunum and ileum, especially toward the lower part of Meckel's diverticulum. The part of small intestine was frequently distended with gas, and also showed mucosal congestion and hemorrhages with varying degrees. Sometimes, the intestinal mucosa was thickened, and also covered with fibronecrotic psuedomembrane. In addition, there were focal necrosis and severely multifocal ulcreation in the mucosa of small intestine. Major histopathological findings included villous necrosis and erosion of the small intestine covering with lots of bacterial colonies, inflammatory cell infiltration in the lamina propria, and dilatation and hyperplasia of crypts. Luminal exudate contained bacterial colonies, fibrin, erythrocytes, and desquamated epithelium. Thirteen(61.9%) out of 21 NE-occurring farms were complicated with intestinal coccidiosis.

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Purification and Characterization of an Antiviral Ribosome-inactivating Protein from Chenopodium album L.

  • Cho, Kang-Jin;Lee, Si-Myung;Kim, Yeong-Tae;Hwang, Young-Soo
    • Journal of Applied Biological Chemistry
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    • v.43 no.3
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    • pp.125-130
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    • 2000
  • An antiviral protein (CAP30) with ribosome-inactivating activity was purified from the leaves of Chenopodium album L. through ammonium sulfate precipitation and column chromatography using S-Sepharose, Blue-Sepharose, FPLC Suprose12 HR, and FPLC Mono-S. The molecular wight of CAP30 was estimated to be 30kD. CAP30 was thermostable, maintaing its activity even after incubation at $70^{\circ}C$ for 30 min, and was stable in the pH range of 6 to 9. In a cell-free in vitro translation system using rabbit reticulocyte lysate, protein synthesis was inhibited by the addition of CAP30 with an $IC_{50}$ of 2.26pM. The comparison of N-terminal amino acid sequences of this protein with known ribosome-inactivating proteins (RIPs) revealed that it had some sequence homology with PAP-S and PAP-R from pokeweed (Phytolacca americana)and dodecandrin from P. dodecandra, but had no sequence homology with RIPs from other plants belonging to different orders. The mosaic symptoms on tobacco leaves caused by cucumber mosaic virus infection was completely inhibited by 100 ng/ml of the pure CAP30 protein.

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