• Title/Summary/Keyword: Cell wall

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Thymol and eugenol in essential oils enhance phage endolysin LysECP26-mediated cell wall disruption of Escherichia coli O157:H7

  • Park, Do-Won;Lee, Jong Hun;Park, Jong-Hyun
    • Korean Journal of Food Science and Technology
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    • v.53 no.6
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    • pp.819-822
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    • 2021
  • To enhance phage endolysin-mediated cell wall disruption of Escherichia coli O157:H7, the cells were co-treated with aromatic compounds, namely thymol or eugenol, found in essential oils and endolysin LysECP26. Interestingly, the minimal inhibitory concentrations of LysECP26 was four times lower when used in combination with either of the two compounds than when it was used alone. This synergistic activity was also confirmed by viable cell counting. Within 1 h of LysECP26 and eugenol or thymol co-treatment to the cells, there was a 2.3 or 3.8 log CFU/mL reductions, respectively. Additionally, field emission scanning electron microscopy showed cell wall disruption and severe morphological alterations of the cells in case of the combination treatments. Therefore, endolysin and thymol or eugenol co-treatment can help in developing efficient bio-control strategies against gram-negative pathogen E. coli O157:H7.

Research on three-point bending fatigue life and damage mechanism of aluminum foam sandwich panel

  • Wei Xiao;Huihui Wang;Xuding Song
    • Steel and Composite Structures
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    • v.51 no.1
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    • pp.53-61
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    • 2024
  • Aluminum foams sandwich panel (AFSP) has been used in engineering field, where cyclic loading is used in most of the applications. In this paper, the fatigue life of AFSP prepared by the bonding method was investigated through a three-point bending test. The mathematical statistics method was used to analyze the influence of different plate thicknesses and core densities on the bending fatigue life. The macroscopic fatigue failure modes and damage mechanisms were observed by scanning electron microscopy (SEM). The results indicate that panel thickness and core layer density have a significant influence on the bending fatigue life of AFSP and their dispersion. The damage mechanism of fatigue failure to cells in aluminum foam is that the initial fatigue crack begins the cell wall, the thinnest position of the cell wall or the intersection of the cell wall and the cell ridge, where stress concentrations are more likely to occur. The fatigue failure of aluminum foam core usually starts from the semi-closed unit of the lower layer, and the fatigue crack propagates layer by layer along the direction of the maximum shear stress. The results can provide a reference for the practical engineering design and application of AFSP.

Paeonia lactiflora Inhibits Cell Wall Synthesis and Triggers Membrane Depolarization in Candida albicans

  • Lee, Heung-Shick;Kim, Younhee
    • Journal of Microbiology and Biotechnology
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    • v.27 no.2
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    • pp.395-404
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    • 2017
  • Fungal cell walls and cell membranes are the main targets of antifungals. In this study, we report on the antifungal activity of an ethanol extract from Paeonia lactiflora against Candida albicans, showing that the antifungal activity is associated with the synergistic actions of preventing cell wall synthesis, enabling membrane depolarization, and compromising permeability. First, it was shown that the ethanol extract from P. lactiflora was involved in damaging the integrity of cell walls in C. albicans. In isotonic media, cell bursts of C. albicans by the P. lactiflora ethanol extract could be restored, and the minimum inhibitory concentration (MIC) of the P. lactiflora ethanol extract against C. albicans cells increased 4-fold. In addition, synthesis of $(1,3)-{\beta}-{\small{D}}-glucan$ polymer was inhibited by 87% and 83% following treatment of C. albicans microsomes with the P. lactiflora ethanol extract at their $1{\times}MIC$ and $2{\times}MIC$, respectively. Second, the ethanol extract from P. lactiflora influenced the function of C. albicans cell membranes. C. albicans cells treated with the P. lactiflora ethanol extract formed red aggregates by staining with a membrane-impermeable dye, propidium iodide. Membrane depolarization manifested as increased fluorescence intensity by staining P. lactiflora-treated C. albicans cells with a membrane-potential marker, $DiBAC_4(3)$ ((bis-1,3-dibutylbarbituric acid) trimethine oxonol). Membrane permeability was assessed by crystal violet assay, and C. albicans cells treated with the P. lactiflora ethanol extract exhibited significant uptake of crystal violet in a concentration-dependent manner. The findings suggest that P. lactiflora ethanol extract is a viable and effective candidate for the development of new antifungal agents to treat Candida-associated diseases.

Result of Complete Resection of T3 Non-Small Cell Lung Cancer Invading the Chest Wall (흉벽침습이 있던 T3 비소세포암환자의 완전절제후의 결과)

  • 최창휴;임수빈;김재현;조재일;백희종;박종호
    • Journal of Chest Surgery
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    • v.34 no.12
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    • pp.924-929
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    • 2001
  • Backgroun : The long-term survival after operation of patients with lung cancer invading the chest wall is known to be related to regional nodal involvement, completeness of resection and depth of chest wall involvement. In this study results of complete resection are reviewed to determine survival charateristics. Material and Method: Of 680 consecutive patients who were operated on for primary non-small cell carcinoma between 1988 and 1998, we retrospectively reviewed 55 patients(8.0%) who had complete resection for lung cancer invading the chest wall or parietal pleura. Result: Resection of the chest wall was on bloc in 29 patients(47.3%), and extrapleural in 26(52.7%). In the patients undergoing extrapleural resection, the depth of chest wall invasion was confined to the parietal pleura in all patients(100%). In the patients underging en bloc resection, the pathologic depth of invasion was into the parietal pleura alone in 9(31.0%) and into the chest wall in 20(69.0%). The follow-up rate of these patients was 100%. Hospital mortality was 5.4%(n=3). The actuarial 5-year survival rate was 26% for all hospital survivors(n=52). The actuarial 5-year survival rate of patients with T3N0M0 disease(29%) was better than that of T3N2M0 disease(18%), however, there was no significant(p=0.30) difference. The depth of chest wall invasion had no statistically significant effect on survival in our series, neither for patients with involved lymphatic metastasis nor for those without(p=0.99). Conclusion: These observations indicate that the good five year survival in patients with T3 NSCLC invading the chest wall resulted from complete resection. Survival of patients with lung cancer invading the chest wall after complete resection is dependent on the extent of nodal involvement and much less so on the depth of chest wall invasion.

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Frequency improvement of protoplast fusion in coryneform bacteria (Coryne형 제균의 원형질체 융합빈도 향상)

  • 김종헌;임번삼;이세영;전문진
    • Korean Journal of Microbiology
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    • v.23 no.3
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    • pp.190-196
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    • 1985
  • For frequency improvement of protoplast fusion in Brevibacterium flavum, Brevibacterium lactofermentum lactofermentum and Corynebacterium glutamicum, the effect of plasma expanders on fusion and cell wall regeneration, compatison between direct and two-step selection method, tendency of fusion frequency according to pH of fusion fluid and polyethylene glycol concentration were examined. By addition of 3% polyvinyl pyrrolidone to cell wall regeneration medium, regeneration frequencies were expressed 23 (Brevibacterium lactofermentum), 10.4 (Brevibacterium flavum) and 2.7 (Corynebacterium glutamicum) times higher than those of none polyvinyl pyrrolidone medium respectively.

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Switching current density for spin transfer torque magnetic random access memory with Dzaloshinskii-Moriya Interaction

  • Song, Kyungmi;Lee, Kyung-Jin
    • Proceedings of the Korean Magnestics Society Conference
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    • 2015.05a
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    • pp.78-79
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    • 2015
  • We investigate the switching current for various cell diameters and DM interaction. We find that the current density for switching can depend strongly on the cell size when the switching is governed by the domain wall motion. Moreover the switching current density is also strongly influenced by DM interaction. In the presentation, we will discuss the effect of domain wall formation and more various DMI constant on the switching current desity in detail.

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Plant Cell Wall as an Inducer of Pectate Lyase of Erwinia rhapontice (Erwinia rhapontici의 Pectate Lyase를 유도하는 식물 세포벽)

  • 최재을;한광섭
    • Korean Journal Plant Pathology
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    • v.12 no.1
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    • pp.129-131
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    • 1996
  • Pecatate lyase(Pel)는 펙틴과 펙틴산을 분해하며, 기주식물의 감염에 관여한다. Erwinia rhapontici에 있어서 기주와 병원균이 병원성과의 상호관계를 구명하기 위하여 pectate lyase(Pel) 활성에 미치는 식물체 추출물과 세포벽의 효과를 검토하였다. 본 균은 glycerol이 포함된 minimal salts(MSG) 배지와 식물체 추출물이 첨가된 MSP 배지에서는 Pel 활성이 검출되지 않았다. 그러나 배추, 상추 잎, 감자 괴경, 셀러리 잎자루, 양파 인경, 당근 뿌리의 세포벽이 첨가된 MSP 배지에서는 Pel의 활성이 검출되었다. Pel을 유도하는 식물 인자는 불용성이고, 열처리에 불안전하였다.

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A Case of Lymphoma Developing From the Wall of Chronic Empyema (악성 늑막 림프종이 합병된 만성 농흉 1례)

  • 김길동
    • Journal of Chest Surgery
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    • v.26 no.7
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    • pp.571-574
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    • 1993
  • We present a rare case of malignant lymphoma developing from the wall of chronic empyema thoracis. A 54-year old man with a 35 year history of tuberculosis empyema was admitted due to right chest pain and general weakness for 2 months. Under the impression of chronic empyema thoracis with destroyed right lung and tumor on posterior costophrenic sulcus, pleuropneumonectomy including tumor was performed as a single procedure through a right thoracotomy. The tumor arose from the thickened pleura, and it was histologically and immunologically diffuse large cell[non-cleaved] B-cell non-Hodgkin`s lymphoma [NHL]

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Respection of Pectic Enzymes Among the Hydrolysis Enzymes of Plant Cell Wall (식물세포벽 가수분해효소 중 펙틴계효소에 대한 고찰)

  • 최동원;김인규
    • The Korean Journal of Food And Nutrition
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    • v.9 no.1
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    • pp.92-98
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    • 1996
  • Pectic materials, which are widely spread in the plant cell wall as plant carbohydrates, plays a great role in food Industry that acts as a softening agent of fruits and vegetables, and gel forming agents. To study physiochemical properties and industrial applications of pectic enzymes that hydrolyzes pectin, classification, assay method and Industrial application are reviewed based on previous results.

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Observation of Soft-Rot Wood Degradation Caused by Higher Ascomyceteous fungi

  • Lee, Yang-Soo
    • Mycobiology
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    • v.28 no.1
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    • pp.47-50
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    • 2000
  • The capability of higher ascomyceteous fungi to cause typical soft-rot decay for wood under laboratory conditions is reviewed and discussed. Fungi tested were extremely active in the decomposition of timbers. Scanning electron micrographs illustrated typical soft-rot decay pattern of higher wood decay ascomycetes, with the exception of H. trugodes that caused white-rot decay. Most of the fungi tested could be grouped as soft-rot fungi that showed typical soft-rot type II. Hypha confined primarily to the resin canals in softwoods or vessel elements in hardwoods and spread tracheid to tracheid via pits of cell wall to cell wall with mechanical force.

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