• The Journal of Internal Korean Medicine
• /
• v.28 no.3
• /
• pp.442-452
• /
• 2007

Objectives : The purpose of this study was to investigate the toll-like receptor (TLR)-4 mediated anti-inflammatory effects of extract from Shigyungbanha-tang (SBT) on the peritoneal macrophage. Methods : To evaluate of TLR-4 mediated inflammatory of SBT. we examined NO and cytokine production in TRL-4 ligand (LPS : lipopolysaccharide) induced macrophages. Furthermore, we examined its molecular mechanism using western blot. Results : Extract from SBT itself does not have any cytotoxic effect in the peritoneal macrophages. Extract from SBT reduced LPS-induced nitric oxide (NO). tumor necrosis factor-alpha ($TNF-{\alpha}$), interleukin (IL)-6 and IL-12 production in peritoneal macrophages. SBT inhibited degradation of inhibitor kappa B-alpha ($I{\kappa}B-{\alpha}$) in the TLR-4 mediated peritoneal macrophages. Conclusions : These results suggest that SBT inhibits NO and cytokines production through inhibiting nuclear factor-kappaB (NF-${\kappa}$B) activation in peritoneal macrophage and that SBT may be beneficial oriental medicine for inflammation.

• Nuclear Engineering and Technology
• /
• v.25 no.4
• /
• pp.570-587
• /
• 1993

Recently a number of severe fuel degradation events, seemingly due to internal secondary hydriding, have been reported. This paper reviews internal hydriding of defected zircaloy cladding. First, the history of zircaloy cladding development and the environment of the zircaloys in service in the nuclear reactor are introduced. Fundamental aspects of zircaloy hydriding, such as hydrogen permeability in zirconium oxide, terminal solubility and precipitation in zirconium and its alloys, and the deleterious effect of hydrides are reviewed. The mechanism of massive internal hydriding in defected zircaloy fuel rods is qualitatively described based on the observed phenomena. Significant factors affecting the hydriding process are discussed. A quantitative model for the massive hydriding as a part of an effort to mitigate fuel degradation is briefly mentioned and necessary information and recommended future work for improvement of the model are outlined.

• Archives of Craniofacial Surgery
• /
• v.20 no.5
• /
• pp.297-303
• /
• 2019

Background: Absorbable plates are widely used in open reduction and internal fixation surgeries for facial bone fractures. Absorbable plates are made of polyglycolic acid (PGA), polylactic acid (PLA), polydioxane (PDS), or various combinations of these polymers. The degradation patterns of absorbable plates made from different polymers and clinical courses of patients treated with such plates have not been fully identified. This study aimed to confirm the clinical courses of facial bone fracture patients using absorbable plates and compare the degradation patterns of the plates. Methods: A retrospective chart review was conducted for 47 cases in 46 patients who underwent open reduction and internal fixation surgery using absorbable plates to repair facial bone fractures. All surgeries used either PLA/PGA composite-based or poly-L-lactic acid (PLLA)/hydroxyapatite (HA) composite-based absorbable plates and screws. Clinical courses were confirmed and comparisons were conducted based on direct observation. Results: There were no naturally occurring foreign body reactions. Post-traumatic inflammatory responses occurred in eight patients (nine cases), in which six recovered naturally with conservative treatment. The absorbable plates were removed from two patients. PLA/PGA compositebased absorbable plates degraded into fragments with non-uniform, sharp surfaces whereas PLLA/HA composite-based absorbable plates degraded into a soft powder. Conclusion: PLA/PGA composite-based and PLLA/HA composite-based absorbable plates showed no naturally occurring foreign body reactions and showed different degradation patterns. The absorbable plate used for facial bone fracture surgery needs to be selected in consideration of its degradation patterns.

• The Journal of the Acoustical Society of Korea
• /
• v.22 no.2E
• /
• pp.78-86
• /
• 2003

We analyzed the measured acoustic field to explore the characteristics of a horizontal coherence in shallow water. Signal spatial coherence data were obtained in the continental shelf off the east coast of Korea using a horizontal line array. The array was deployed on the bottom of 130 m water depth and a sound source was towed at 26 m depth in the source-receiver ranges of 1-13 ㎞. The source transmitted 200 ㎐ pure tone. Topography and temperature profiles along the source track were measured to investigate the relationship between the horizontal coherence and environment variations. The beam bearing disturbance and array signal gain degradation is examined as parameters of horizontal coherence. The results show that the bearing disturbance is about ± 8° and seems to be affected by temporal variations of temperature caused by internal waves. The array signal gains show degradation more than 5㏈ by the temporal and spatial variations of temperature and by the down-sloped topography.

• The Journal of Pediatrics of Korean Medicine
• /
• v.24 no.1
• /
• pp.93-103
• /
• 2010

Objectives The purpose of this study was to examine the pathway of anti-allergic effects of Cheonmaec-tang (CMT). Methods We examined the cell viability, $\beta$-hexosaminidase release, pro-inflammatory cytokines secretion and mRNA expressions, nuclear factor-kappa B (NF-${\kappa}B$) (p65) activation, inbibitor kappa B-alpha ($I{\kappa}B-{\alpha}$) degradation, and MAPKs activation in RBL-2H3 cells pre-treated by CMT of 2.0 mg/ml, 4.0 mg/ml separately. Results We observed that CMT reduced the secretion of $\beta$-hexosaminidase, TNF-$\alpha$, IL-4 and the expression of COX-2 mRNA in RBL-2H3 cells. Furthermore, CMT inhibited the levels of activation of NF-${\kappa}B$ (p65) protein, ERK MAPK, and degradation of $I{\kappa}B-{\alpha}$ in RBL-2H3 cells. Conclusions These results show that CMT has an anti-histamine effect and inhibitory effect of NF-${\kappa}B$ (p65) through regulation of $I{\kappa}B-{\alpha}$ degradation. These suggest that CMT could be used as an anti-allergic medicine.

• Korean Journal of Materials Research
• /
• v.4 no.4
• /
• pp.439-444
• /
• 1994

The influence of the direction of applied compressive stress on degradation mechanism ofpoled PZT sample was studied. When compressive stress perpendicular to poling direction was appliedon poled PZT sample, the degradation phenomena was explained by the diffusion of space chargepolarization. On the contrary, compressive stress parallel to poling direction was applied, it wasexplained by the rearrangement of 90" domains. As the grain size increased, the degradation phenomenawas promoted. It is attributed to different internal stress due to difference of grain size. of grain size.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.14 no.3
• /
• pp.38-46
• /
• 2005

The destructive method is reliable and widely used for 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. In this study, various nondestructive evaluation(NDE) parameters of the Barkhausen noise method, such as MPA(Maximum Peak Amplitude), RMS, IABNS(Internal Area of Barkhausen Noise on Signal) and average amplitude of frequency spectrum are investigated and correlated with thermal damage level of 2.25cr-1.0Mo steel using wavelet analysis. Those parameters tend to increase while thermal degradation proceeds. It also turns out that the wavelet technique can help to reduce experimental false call in data analysis.

• Journal of Applied Biological Chemistry
• /
• v.50 no.4
• /
• pp.221-226
• /
• 2007

The high molecular-weight mucilage extracted and purified from cactus fruit of Opuntia ficus-indica var. Saboten was degraded by the cell-free culture filtrate of a fungus isolated from soil. TLC analysis of the polymeric mucilage after incubation with the fungal culture filtrate confirmed its degradation. When the degradation products were tested for their qualitative reactions with ninhydrin and phenol-sulfuric acid, only phenol-sulfuric acid gave positive development, and ninhydrin did not show any observable color reaction. This coloring reaction suggested the presence of a carbohydrate without an amino group within the mucilage. Analyses by HPLC and liquid gel permeation chromatography on sephadex G-100 also provided additional information on degradation of the mucilage by the fungal culture filtrate. The sequences of ITS-5.8S rDNA from the fungal isolate that was cultivated for the preparation of mucilage-degrading enzyme showed 99% similarity to those of Pestalotiopsis aquatica.

• Computers and Concrete
• /
• v.19 no.1
• /
• pp.87-98
• /
• 2017

In recent year, the coat layer drops and the rebar rust of bridge parapets, which caused the structural performance degradation. In order to achieve the comprehensive rehabilitation, ultra high performance cementitious composites is proposed to existing RC parapet rehabilitation. The influence factors of UHPCC rehabilitation includes two parts, i.e., internal factors related with material, such as UHPCC layer thickness, corrosion ratio of rebars, fiber volume fraction, and external factors related with the load, such as impact speeds, impact angles, vehicle mass. The influence of the factors was analyzed in this paper based on the nonlinear finite element. The analysis results of the maximum dynamic deformation and the peak impact load of parapets revealed the influence of the internal factors and the external factors on anti-collision performance and degree degradation. This research may provide a reference for the comprehensive multifunctional rehabilitation of existing bridge parapets.

• Korean Journal of Agricultural Science
• /
• v.42 no.4
• /
• pp.369-374
• /
• 2015

This study was conducted to compare the glucose, lactate, and nucleotide degradation products content of cooked beef steaks from Korean Hanwoo (quality grade: 1) and Australian cattle (Bos indicus, grain-fed for 100 d) by internal temperature. The loins (M. longissimus dorsi) and top rounds (M. semimembranosus) from two cattle breeds were cut into about 2 cm thickness and then cooked in a $180^{\circ}C$ electronic oven until internal temperature attained to 50, 70, or $90^{\circ}C$. Regardless of internal temperature, glucose content was higher (P<0.05) in cooked loin and top round steaks from Hanwoo compared to those from Australian cattle. Lactate content was shown to be lower (P<0.05) in cooked steaks from Hanwoo than in those from Australian cattle. Lower (P<0.05) hypoxanthine and higher (P<0.05) guanosine 5'-monophosphate, inosine 5'-monophosphate, inosine contents were observed in cooked steaks from Hanwoo. Furthermore, glucose content tended to be decreased by internal temperature but nucleotide degradation products content was not changed by internal temperature. Therefore, these findings suggest that cooked Hanwoo beef steaks had higher flavor precursors related to sweet and umami tastes than cooked Australian beef steaks