• Title/Summary/Keyword: Destructive

Search Result 2,371, Processing Time 0.032 seconds

Biochemical Aspect of Superoxide Toxicity to Plant Mitochondria (식물 미토콘드리아에 대한 Superoxide독성의 생화학적 측면)

  • Jung, Jin;In, Man-Jin
    • Applied Biological Chemistry
    • /
    • v.32 no.1
    • /
    • pp.23-29
    • /
    • 1989
  • Biochemical consequence of the accumulation in cells of superoxide $(O^{-}_{2})$ which was proposed to be probably a common chemical factor in the secondary process of the mechanism of chilling injury as well as in the visible light photodamage in cells of higher plants, has been investigated in the present work. Especially focused was the destructive effect of $O^{-}_{2}$ on the biochemical activity of mitochondria, as informations which support the suggestion that mitochondrial inner membrane is the major site of $O^{-}_{2}$ production have been collected. Mitochondria and submitochondrial particles (SMP) were prepared from soybean hypocotyls for this case study. When SMP were treated with the electrolytically produced $O^{-}_{2}$ they suffered not only inhibition of the membrane-bound enzymes as demonstrated by cytochrome c oxidase, but also lipid peroxidation of membrane as proved by malondialdehyde production. Malate dehydrogenase present in the protein extract from mitochondrial matrix was also inhibited by the $O^{-}_{2}$ treatment. These results exhibited the chaotic effect of the overproduction and accumulation of $O^{-}_{2}$ in cells under a certain abnormal circumstance such as environmental stress on the physiological function of mitochondrial; disruption of the cellular metabolic pathways and the structural integrity of membrane.

  • PDF

Histopathological changes of epithelium following the exposure of N-methyl-N-nitro-N-nitrosoguanidine in Manila clam, Ruditapes philippinarum (N-methyl-N-nitro-N-nitrosoguanidine 노출에 따른 바지락 (Ruditapesphilippinarum) 상피조직의 병리조직학적 반응)

  • Lee, Mu-Kun;Huh, Min-Do
    • Journal of fish pathology
    • /
    • v.18 no.3
    • /
    • pp.247-258
    • /
    • 2005
  • To understand responses of bivalve tissues to various injurious agents, histopathological observation was done in the Manila clam, Ruditapes hilippinarum, during 240 hours after an intramuscular injection of N-methyl-N-nitro-N-nitrosoguanidine (MNNG). Some histopathological changes were observed with the epithelia of stomach, midgut, hindgut, digestive diverticula and gonads after injecting MNNG. The earliest degenerative changes were recognized in the epithelium of midgut 12 hours after the injection. Partial or complete, epithelial destruction was constantly accompanied by the massive infiltration of a mononuclear, necrotic cell group including hemocytes. At 144 hours later, gonads showed the necrotic desquamation of their germinal epithelia. Nearly all of the infiltrated cells within the destructive epithelium were suggested to be hemocytes, from the binding property with a hemocyte-specific lectin, Ricinus communis (RCA-1). From these results it was concluded that the epithelium of digestive system is vulnerable to parenteral MNNG and hemocytes might be deeply involved in this MNNG-induced destruction of the digestive epithelium.

Petrology of the Cretaceous Igneous Rocks in the Mt. Baegyang Area, Busan (부산 백양산 지역의 백악기 화산-심성암류에 대한 암석학적 연구)

  • 김향수;고정선;윤성효
    • The Journal of the Petrological Society of Korea
    • /
    • v.12 no.1
    • /
    • pp.32-52
    • /
    • 2003
  • The Mt. Baegyang in Busan, composed of sedimentary basement rocks (Icheonri Formation), andesite (lava), andesitic pyroclastic rocks, fallout tuff and tuffaceous sedimentary rocks, rhyolitic pyroclastic rocks, intrusive rocks (granite-porphyry, felsite, and biotite-granite) of Cretaceous age in ascending order. The volcanic rocks show a section of composite volcano which comprised alternation of andesitic lava and pyroclasitc rocks, rhyolitic pyrocalstic rocks (tuff breccia, lapilli tuff, fine tuff) from the lower to the upper strata. From the major element chemical analysis, the volcanic and intrusive rocks belong to calc-alkaline rock series. The trace element composition and REE patterns of volcanic and plutonic rocks, which are characterized by a high LILE/HFSE ratio and enrichments in LREE, suggest that they are typical of continental margin arc calc-alkaline rocks produced in the subduction environment. Primary basaltic magma might have been derived from partial melting of mantle wedge in the upper mantle under destructive plate margin. Crystallization differentiation of the basaltic magma would have produced the calc-alkaline andesitic magma. And the felsic rhyolitic magma seems to have been evolved from andesitic magma with crystallization differentiation of plagioclase, pyroxene, and hornblende.

Allogenic Grafting of Cryopreserved Fat Cell (냉동보관된 지방세포의 동종이식)

  • Lee, Jong Hoon;Choi, Hong Hyeuk
    • Archives of Plastic Surgery
    • /
    • v.35 no.4
    • /
    • pp.385-392
    • /
    • 2008
  • Purpose: The most effective methods of harvesting, preparing, and injecting autologous fat grafts have been inconsistent and conflicting. With its limitation as resorption in fat grafting, handling various techniques affect adipocyte survival, and is crucial to optimizing its long-term survival. To improve graft survival, re-implantation of cryopreserved adipocytes was developed. In addition, adipocytes do not induce immune rejection in response to non-self lymphocytes in a mixed lymphocyte reaction. The purpose of this study is to analyze the changes in cryopreserved adipocytes so as to determine the most efficient long-term storage period, and to analyze the changes in cryopreserved allografted adipocytes so as to determine the efficacy of cryopreserved adipocytes allografting. Methods: Fat tissues were harvested from the inguinal and retroperitoneal fat pad of mice. After the centrifugation of the harvested fat tissues, they were disintegrated with collagenase. The adipocytes were obtained by centrifugation of the disintegrated fat tissues. The adipocytes were treated as follows: (1) They were examined for weight and then frozen at $-20^{\circ}C$(n=25). For four months, each five frozen samples were taken and examined for weight and histologic changes in the 1st week, the 1st month, the 2nd month, the 3rd month, and the 4th month, respectively. (2) The adipocytes were immediately frozen at $-20^{\circ}C$(n=125). For four months, five frozen samples were taken, and allografted in the same time period as above. Finally, for four months, five cryopreserved allografted adipocytes were taken and examined for histologic changes in the same time period as above. Results: (1) Significant weight changes and histologic findings with inflammatory and destructive changes were observed in the cryopreserved adipocytes in three months. (2) Significant fat necrotic changes in the histologic changes with Hematoxylin and eosin stain were observed in the cryopreserved allografted adipocytes since the first week, independent of the freezing period. Conclusion: The study results show that the adipocytes that were cryopreserved for more than three months underwent obvious weight reductions and necrotic changes, and the adipocytes that were allografted without freezing were viable for four months, but the cryopreserved allografted adipocytes had obvious necrotic changes since the first week regardless of the freezing period.

A Clinical Study of Nasal Synechiae Causing by Closed Reduction for Nasal Bone Fractures (코뼈골절 비관혈적 정복술 후 점막 유착에 대한 연구)

  • Choi, Hwan Jun;Lee, Yong Seok;Choi, Chang Yong;Tark, Min Sung
    • Archives of Plastic Surgery
    • /
    • v.36 no.2
    • /
    • pp.188-193
    • /
    • 2009
  • Purpose: Several authors reported about the post - traumatic nasal aesthetic complications. However, the study for functional or intra - nasal complications has been reported not enough. The aim of this study is to observe the incidence of intranasal synechia. Methods: We reviewed the data from 401 consecutive patients with nasal bone fracture from september 2006 to December 2007. We enforced evaluation with preoperative CT in all patients but postoperative CT within complicated patients. We classified the nasal bone fracture according to the anatomy and severity of fracture. Type I is nasal tip fracture(15%, n = 59), Type II is simple lateral without septal injury(38%, n = 152), Type III is simple lateral with septal injury(23%, n = 92), Type IV is closed comminuted(20%, n = 82), Type V is open comminuted or complicated(4%, n = 16). We studied 98 patients with nasal bone fracture who had postoperative symptoms or undergone postoperative endoscopic evaluation. And then we evaluated the postoperative endoscopic finding and nasal synechal formation after operation. Results: The incidence of intranasal synechiae was 15%(n = 62). According to the endoscopic findings, the incidence of intranasal synechiae was 10%(n = 6) in Type I, 8%(n = 12) in Type II, 16%(n = 15) in Type III, 24%(n = 20) in Type IV, and 56%(n = 9) in Type V. Additionally, the incidence of subjective nasal obstruction and olfactory dysfunction is 18%(n = 72) and 13%(n = 51). But the incidence of symptomatic synechiae of nasal obstruction and olfactory dysfunction is 92%(57/62) and 55%(34/62). Conclusion: We identified relatively high prevalence of nasal obstruction and olfactory dysfunction in nasal synechiae. Based on the results of this study, intranasal synechiae really caused airway obstruction(92%). Our data showed significant relationship between intranasal synechiae and severity of the fracture, because of increasing mucosal handling and destructive closed reductional procedures. First of all, education of delicate procedure regarding this subject should be empathized accordingly.

Development of Portable X-ray CT System II - CT Image Reconstruction of Wood using Density Distribution - (현장 적용이 가능한 X선 CT 시스템 개발 II- 밀도분포를 이용한 목재의 CT영상 구성 -)

  • Kim, Kwang-Mo;Lee, Sang-Joon;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
    • /
    • v.34 no.1
    • /
    • pp.23-31
    • /
    • 2006
  • X-ray transit materials with straight path and the its intensity is proportional to the density of materials. Therefore, X-ray has been extensively used as a nondestructive evaluation (NDE) method in various fields. This study was carried out for development of a portable X-ray CT (computed-tomography) system to detect deteriorations of wood members in buildings. Based on the results of our previous study, a procedure of CT image reconstruction was established In order to verify the applicability of developed system, CT images of three wood disks were reconstructed by newly developed procedure and compared with the prototypes. From the results of this study, it was shown that the newly developed system could be used not only to determine the shape, size, and position of defects, but also to find the density distribution in cross section of wood structure members. The density distribution may be utilized to clarify the reason of wood deterioration and to provide the preventive method on how to treat or repair wood buildings. Because it was initial stage of system development, there were some limitations concerned with measuring equipment and image reconstruction algorithm. Especially, measuring time including equipment setup time was longer and measuring accuracy was lower than we expected. Therefore, we planned some additional studies on improvement of equipment and algorithm to enhance the capability of X-ray CT system.

Temperature Prediction Method for Superheater and Reheater Tubes of Fossil Power Plant Boiler During Operation (화력발전 보일러 과열기 및 재열기 운전 중 튜브 온도예측기법)

  • Kim, Bum-Shin;Song, Gee-Wook;Yoo, Seong-Yeon
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.36 no.5
    • /
    • pp.563-569
    • /
    • 2012
  • The superheater and reheater tubes of a heavy-load fossil power plant boiler can be damaged by overheating, and therefore, the degree of overheating is assessed by measuring the oxide scale thickness inside the tube during outages. The tube temperature prediction from the oxide scale thickness measurement is necessarily accompanied by destructive tube sampling, and the result of tube temperature prediction cannot be expected to be accurate unless the selection of the overheated point is precise and the initial-operation tube temperature has been obtained. In contrast, if the tube temperature is to be predicted analytically, considerable effort (to carry out the analysis of combustion, radiation, convection heat transfer, and turbulence fluid dynamics of the gas outside the tube) is required. In addition, in the case of analytical tube temperature prediction, load changes, variations in the fuel composition, and operation mode changes are hardly considered, thus impeding the continuous monitoring of the tube temperature. This paper proposes a method for the short-term prediction of tube temperature; the method involves the use of boiler operation information and flow-network-analysis-based tube heat flux. This method can help in high-temperaturedamage monitoring when it is integrated with a practical tube-damage-assessment method such as the Larson-Miller Parameter.

A Study on the High Frequency Ultrasonic Attenuation Characterization in Artificially Aging Degraded 2.25Cr-1Mo Steel (2.25Cr-1Mo 강 인공 열화재의 고주파수 초음파 감쇠특성에 관한 연구)

  • Park, Ik-Keun;Park, Un-Su;Kim, Chung-Seok;Kim, Hyun-Mook;Kwun, Sook-In;Byeon, Jai-Won
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.21 no.4
    • /
    • pp.439-445
    • /
    • 2001
  • The destructive method is reliable and widely used lot the estimation of material degradation but, it have time-consuming and a great difficulty in preparing specimens from in-service industrial facilities. Therefore, the estimation of degraded structural materials used at high temperature by nondestructive evaluation such as electric resistance method, replica method, Barkhausen noise method, electro-chemical method and ultrasonic method are strongly desired. Ultrasonic nondestructive evaluation technique has been reported good to attain efficiency of measurement, high sensitivity of measurement, and rapidity and reliability of result interpretation. In this study, it was verified experimentally the feasibility of the evaluation of degraded 2.25Cr-1Mo steel specimens which were prepared by the isothermal aging heat treatment at $630^{\circ}C$ by high frequency longitudinal wave method investigating the change of attenuation coefficient by FFT analysis and wavelet transform. Because of carbide precipitation increase and spheroidization near grain boundary of microstructure to aging degradation, attenuation coefficient had a tendency to increase as degradation proceeded. It was identified possibly to evaluate degradation using the characteristics of high-frequency ultrasonics. Frequency dependence of ultrasonic attenuation coefficient to aging degradation appeared large, which made sure that attenuation coefficient is an important parameter for evaluation of aging degradation.

  • PDF

Development of Nondestructive Sorting Method for Brown Bloody Eggs Using VIS/NIR Spectroscopy (가시광 및 근적외선 전투과 스펙트럼을 이용한 갈색 혈란 비파괴선별 방법 개발)

  • Lee, Hong-Seock;Kim, Dae-Yong;Kandpal, Lalit Mohan;Lee, Sang-Dae;Mo, Changyeun;Hong, Soon-Jung;Cho, Byoung-Kwan
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.34 no.1
    • /
    • pp.31-37
    • /
    • 2014
  • The aim of this study was the non-destructive evaluation of bloody eggs using VIS/NIR spectroscopy. The bloody egg samples used to develop the sorting mode were produced by injecting chicken blood into the edges of egg yolks. Blood amounts of 0.1, 0.7, 0.04, and 0.01 mL were used for the bloody egg samples. The wavelength range for the VIS/NIR spectroscopy was 471 to 1154 nm, and the spectral resolution was 1.5nm. For the measurement system, the position of the light source was set to $30^{\circ}$, and the distance between the light source and samples was set to 100 mm. The minimum exposure time of the light source was set to 30 ms to ensure the fast sorting of bloody eggs and prevent heating damage of the egg samples. Partial least squares-discriminant analysis (PLS-DA) was used for the spectral data obtained from VIS/NIR spectroscopy. The classification accuracies of the sorting models developed with blood samples of 0.1, 0.07, 0.04, and 0.01 mL were 97.9%, 98.9%, 94.8%, and 86.45%, respectively. In this study, a novel nondestructive sorting technique was developed to detect bloody brown eggs using spectral data obtained from VIS/NIR spectroscopy.

Cultivation conditions for mass production of detoxifying bacterium Pseudomonas sp. HC1 of tolaasin produced by Pseudomonas tolaasii (버섯 세균성갈색무늬병원균(Pseudomonas tolaasii)의 독소(tolaasin) 저해균 Pseudomonas sp. HC1의 대량배양을 위한 최적 배양조건)

  • Lee, Chan-Jung;Yoo, Young-Mi;Han, Ju-Yeon;Jhune, Chang-Sung;Cheong, Jong-Chun;Moon, Ji-Won;Kong, Won-Sik;Suh, Jang-Sun;Han, Hye-Su;Cha, Jae-Soon
    • Journal of Mushroom
    • /
    • v.12 no.1
    • /
    • pp.35-40
    • /
    • 2014
  • Several bacteria are known as the causal agents of diseases of the cultivated button mushroom(Agaricus bisporus) and oyster mushroom(Pleurotus ostreatus). Pseudomonas tolaasii is the causal agent of brown blotch disease of commercial mushrooms. Pseudomonas sp. HC1 is a potent biological control agent to control brown blotch disease caused by Pseudomonas tolaasii. This can markedly reduce the level of extracellular toxins (i.e., tolaasins) produced by Pseudomonas tolaasii, the most destructive pathogen of cultivated mushrooms. To define the optimum conditions for the mass production of the Pseudomonas sp. HC1, we have investigated optimum culture conditions and effects of various nutrient source on the bacterial growth. The optimum initial pH and temperature were determined as pH 5.0 and $20^{\circ}C$, respectively. The optimal culture medium for the growth of tolaasin inhibitor bacterium was determined as follows: 0.9% dextrin, 1.5% yest extract, 0.5% $(NH_4)_2HPO_4$, 4mM $FeCl_3$, and 3.0% cysteine.