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Anti-inflammatory Activity of Crinum asiaticum Linne var. Japonicum Extract and its Application as a Cosmeceutical Ingredient (문주란의 항염효과와 화장료적 특성)

  • Kim, Ki-Ho;Kim, Young-Heui;Kim, Ki-Soo;Park, Sun-Hee;Lee, Soo-Hee;Kim, Young-Jin;Kim, Young-Sil;Kim, Jong-Heon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.32 no.1 s.55
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    • pp.59-64
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    • 2006
  • Crinum asiaticum Linne var. japonicum has long been used as a rheumatic remedy, an anti-pyretic, an anti-ulcer treatment, and for the alleviation of local pain and fever in Korea and Malaysia. In order to investigate the possibility of Crinum asiaticum Linne var. japonicum extract as a cosmetic ingredient, we measured its anti-inflammatory effect by inhibition of iNOS (inducible nitric oxide synthase), and the release of PGE2, IL-6, and IL-8. HPLC experiment after extraction with 95% ethanol at pH 3.5 showed that Crinum asiaticum Linne var. japonicum was mainly composed of lycorine (up to 1%), a well-known immunosuppressant. The content of lycorine varied depending on the type of tissue analyzed and the extraction method. In anti-inflammatory assay for inhibition of nitric oxide formation on lipopolysaccharide (LPS)- activated mouse macrophage RAW 264.7 cells, the ethanolic extract of Crinum asiaticum showed inhibitory activity of NO production in dose-dependent manner ($IC_{50} = 83.5 {\mu}g/mL$). Additional study by RT-PCR demonstrated that the extract of Crinum asiaticum significantly suppressed the expression of the iNOS gene. Moreover, the extract of Crinum asiaticum did not show my cytotoxicity, but did show cell proliferation effect against LPS ($10{\sim}60%$ increase of tell viability). In an assay to determine inhibition of the $H_2O_2$-activated release of PGE2, IL-6, and IL-8 in human normal fibroblast cell lines, the release of PGE2 and IL-6 was almost completely inhibited above concentrations of 0.05% and 1%, respectively. Moreover, the release of IL-8 was completely inhibited over the entire range of concentrations (> 0.0025%). The result showed that the extract of Crinum asiaticum Linne var. japonicum has sufficient anti-inflammatory effect. There-fore, Crinum asiaticum Linne var. japonicum extract may be useful as an ingredient of cosmetic products.

The Immunohistochemical Analysis for the Expression of Survivin, HSP, and Bcl-2 in Non-small Cell Lung Carcinoma (비소세포폐암에서 Survivin, HSP 및 Bcl-2 발현에 관한 면역조직화학적 분석)

  • Hong, Hyun-Ju;Hong, Seok-Gyun;Lee, Kye-Young;Kim, Woo-Ho;Lee, Choon-Taek;Yoo, Chul-Gyu;Han, Sung-Koo;Shim, Young-Soo;Kim, Young-Whan
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.5
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    • pp.441-452
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    • 2002
  • Background : Anti-apoptotic proteins may be involved in tumor development, progression and the response to treatment, Bcl-2 is by far the most studied anti-apoptotic protein. A novel inhibitor of apoptosis, designated survivin, and the heat shock proteins (HSPs) have recently been found in many human cancers. Immunohistochemical methods were used to determine the expression level of survivin, HSP70 and bcl-2 in non-small cell lung cancer (NSCLC) to evaluate their clinical significance. Materials and Methods : Tissue array slides were obtained from 99 surgically resected NSCLCs. Immunohistochemical staining was performed by an immuno-peroxidase technique using an avidin-biotinylated horseradish peroxidase complex. Anti-survivin rabbit polyclonal antibodies, anti-HSP70 mouse monoclonal antibodies and anti-bcl-2 mouse monoclonal antibodies were used as the primary antibodies. Results : Positive staining of survivin was detected in 33.3% of the cases. Survivin positivity is associated with to females and recurrence. A nonstatistically significant trend toward increased survivin expression was observed in non-smokers, and its expression inversely correlated with the number of cigarettes smoked in smokers. HSP70 was detected in 84.8% but this did not correlated with the clinicopathologic characteristics. Bcl-2 was detected in 18.2% and its expression correlated to tumor recurrence. No significant difference in the median survival time was noted in a comparison of all cases with survivin expression and those without. There was no association between HSP70 or bcl-2 expression and survival. Conclusion : Survivin expression was significantly associated with females and tumor recurrence. In addition its expression was inversely associated with the number of cigarettes smoked. However, HSP70 and bcl-2 expression were not associated with the clinical parameters or survival. This suggests that measuring the survivin levels may be useful in identifying patients at high risk for disease recurrence. Therefore, survivin might be a new diagnostic/therapeutic target in cancer.

Particulate Matter 10 from Asian Dust Storms Induces the Expression of Reactive Oxygen Species, NF-κ, TGF-β and Fibronectin in WI-26 VA4 Epithelial Cells (황사의 PM10이 WI-26 VA4 Cells에서 Reactive Oxygen Species, NFκB, TGF-β, Fibronectin의 발현에 미치는 영향)

  • Park, Kyeong Seon;Kim, Yu Jin;Yoon, Jin Young;Kyung, Sun Young;An, Chang Hyeok;Lee, Sang Pyo;Park, Jeong Woong;Jeong, Sung Hwan
    • Tuberculosis and Respiratory Diseases
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    • v.65 no.6
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    • pp.504-511
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    • 2008
  • Background: Particulate matter may be toxic to human tissue. Ambient air particulate matter ${\leq}10{\mu}m$ in aerodynamic size ($PM_{10}$), which changes under different environmental conditions, is a complex mixture of organic and inorganic compounds. The Asian dust event caused by meteorological phenomena can also spread unique particulate matter in affected areas. We evaluated production of ROS, $TGF-{\beta}$, fibronectin, and $NF{\kappa}B$ by exposing normal epithelial cells to Asian dust particulate matter. Methods: Bronchial epithelial cells were exposed to 0, 50, ${\leq}100{\mu}g/ml$ of a suspension of $PM_{10}$ for 24 h. ROS were detected by measurement of DCF release from DCF-DA by FACScan. $TGF-{\beta}$, fibronectin, and $NF{\kappa}B$ were detected by western blotting. Results: $PM_{10}$ exposure increased the expression of $TGF-{\beta}$, fibronectin, and $NF{\kappa}B$. ROS production and $TGF-{\beta}$ levels were significantly higher with 50 or ${\leq}100{\mu}g/ml$ $PM_{10}$. Fibronectin and $NF{\kappa}B$ production were significantly higher after ${\leq}100{\mu}g/ml$ of $PM_{10}$. Conclusion: $PM_{10}$ from Asian dust particles might have fibrotic potential in bronchial epithelial cells via ROS induction after $PM_{10}$ exposure.

The biologic effects of safflower(Carthamus tinctorius $Linn\acute{e}$) extract and Dipsasi Radix extract on periodontal ligament cells and osteoblastic cells (홍화 추출물이 치주인대세포, 조골세포 활성도에 미치는 영향)

  • Rhyu, In-Chul;Lee, Yong-Moo;Ku, Young;Bae, Ki-Whan;Chung, Chong-Pyoung
    • Journal of Periodontal and Implant Science
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    • v.27 no.4
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    • pp.867-882
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    • 1997
  • Safflower(Carthamus tinctorius $Linn\acute{e}$ has been traditionally used for the treatment of blood stasis, and Dipsasi Radix has been used as a drug for fracture in Chinese medicine. The purpose of present study was to examine the biologic effects of safflower extract and Disasi radix extracts on the periodontal. ligament cells and osteoblastic cells and on the wound healing of rat calvarial defect. The ethanolic extract of safflower blossom, safflower seed and Dipsasi Radix(125, 250, and 500 ${\mu}g/ml$) were prepared as test group, and PDGF-BB(lOng/ml) and unsafonifiable fraction of Zea Mays L.(125, 250, and 500 ${\mu}g/ml$) were employed as positive control. The effects of each agents on the growth and survival, ALPase activity, expression of PDGF-BB receptor, chemotactic response of PDL cell and ATCC human osteosarcoma MG63 cells in vitro were examined. The tissue regenerative effect of each extracts was evaluated by histomorphometric measuring of newly formed bone on the 8mm defect in rat calvaria after oral administration of 3 different dosages groups : 0.02, 0.1 and 0.35g/kg, per day. It was also employed the same dosages of unsaponifiable fraction of Zea Mays L. as positive controls. Safflower blossom extract, safflower seed extract, and Dipsasi Radix extract stimulate the cellular activity of MG63 cells in concentration range of $125-500{\mu}g/ml$, and safflower bolssom extract and safflower seed extract stimulate also the cellular activity of periodontal ligament cells in concentration range of $250-500{\mu}g/ml$. In activity of ALPase, $250-500{\mu}g/ml$ of safflower blossom extracts showed significant stimulating effects on MG63 cells, and the same concentration range of safflower seed extracts showed significant effect on periodontal ligament cells. In the recovery on PDGF-BB receptor expression which was depressed by $IL-1{\beta}$, $125-250{\mu}g/ml$ of safflower blossom extracts and $250-500{\mu}g/ml$ of safflower seed extracts showed significant increasing effect on MG63 cells, and $500{\mu}g/ml$ of safflower blossom extract and $250-500{\mu}g/ml$ of safflower seed extracts showed significant effect on periodontal ligament cells. In chemotactic response, among all tested group, safflower seed extracts only were chemotactic to MG63 cells and periodontal ligament cells in concentration range of $125-500{\mu}g/ml$. Also in the view of bone regeneration in rat calvarial defect model, the only group that was orally administrated 0.35g/kg, day of safflower seed extract showed significant new bone formation. These results suggested that safflower extracts might have a potential possibilities as an useful drug for adjunct to treatment for regeneration of periodontal defect.

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Role of Ghrelin in the Control of Reproductive Endocrine Function (포유류 생식 내분비 기능 조절에서 Ghrelin의 역할)

  • Lee, Sung-Ho
    • Development and Reproduction
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    • v.13 no.4
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    • pp.207-215
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    • 2009
  • Numerous factors can affect the activities of hypothalamus-pituitary-gonad (HPG) hormonal axis, resulting in alteration of reproductive capacity or status such as onset of puberty and menopause. Soon after the finding of leptin, a multifunctional hormone secreted from adipocytes, a close relationship between reproduction and body energy balance have been manifested. Ghrelin, another multifunctional hormone from gastrointestinal tract, is an endogenous ligand of growth hormone secretagogue receptor (GHSR), and is thought to be a counterpart of leptin in the regulation of energy homeostasis. As expected, ghrelin can also modulate the reproductive capacity through the modulation of activities of HPG axis. This paper summarizes the current knowledge on the discovery, gene structures, tissue distribution and roles of ghrelin and GHSRs in mammalian reproduction in particular modulation of reproductive hormone secretion in HPG axis. Like POMC gene expression in pituitary gland, preproghrelin gene can generate a complex repertoire of transcripts which further undergo alternative splicing and posttranslational modifications. Concerning the roles of preproghrelin gene products in the control of body physiology except energy homeostasis, limited knowledge is available so far. Several lines of evidence, however, show the interplay of ghrelin between metabolism and reproduction. In rat and human, the distribution of ghrelin receptor GHSRs (GHSR1a and GHSR1b) has been confirmed not only in the hypothalamus and pituitary which were originally postulated as target of ghrelin but also in the testis and ovary. Expression of the preproghrelin gene in the brain and gonads was also verified, suggesting the local role (s) of ghrelin in HPG axis. Ghrelin might play a negative modulator in the secretions of hypothalamic GnRH, pituitary gonadotropins and gonadal steroids though the action on pituitary is still questionable. Recent studies suggest the involvement of ghrelin in regulation of puberty onset and possibly of menopause entry. It is now evident that ghrelin is a crucial hormomal component in 'brain-gut' axis, and is a strong candidate links between metabolism and reproduction. Opposite to that for leptin, ghrelin signaling is likely representing the 'hunger' state of body energy balance and is necessary to avoid the energy investment into reproduction which has not a top priority in maintaining homeostasis. Further researches are needed to gain a deep insight into the more precise action mechanism and role of ghrelin in reproduction, and to guarantee the successful biomedical applications.

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Studies on Anisakis Type Larvae (Anisakis 형(型) 유충(幼蟲)에 관한 연구(硏究))

  • Lim, Jung Teck
    • Korean Journal of Veterinary Research
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    • v.15 no.2
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    • pp.293-307
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    • 1975
  • As it has been known recently that anisakis type larvae harbouring in marine fishes are a causal agent of zoonosis to human and probably to land living mammal animals, attention was focused on the study on the larvae in an aspect of epidemiology or epizootiology. The present work was conducted from 1966 to 1975 for i) survey on the harbouring status of anisakis type larvae in marine fishes of this country, ii) observation on the response to the experimental infestation of the larvae to the pigs, in the reason that they could well fetid raw fish viscera occasionally containing the larvae as a high protein source of swine food, and iii) observation on the larval resistance and response to vermicidal agents for the purpose of prevention of the larval infection to the mammal animals. The data obtained in the studies were summarized as follows: 1. In the survey on the status of larvae harbouring in main species of marine fishes of this country, 15 species, a total of 1,940 fishes, were observed and the result was summarized in table 2. Average number of larvae, in upper rank of 5 out of all 15 species of fishes, were as highest as 156 larvae ranging 74 to 450 in Pseudosciaena manchurica (chamjogi), 54.5 ranging 15 to 240 in Trichiurus haumela (kalchi), 35.6 ranging 8 to 112 in Trachurus japonica (junggengi), 30.6 ranging 4 to 65 in Parapristipama trilineatum (benjari) and 20.5 ranging 3 to 48 in Nibea argentata (boguchi) respectively. In morphological observation, size of the larvae in the fishes were varied, ranging from 2 to 32mm long, and a tendency to larger size and number of larvae in the fishes, which were wider sea migration, higher age and lager bodily size, was observed The favorite places harbouring the larvae in fishes were mainly around the intraperitoneal viscera such as mesentery, omentum, liver, pyloric suspensory, fat tissue and cloaca, and rarely in body muscles of fish. Fishes heartily infested with the larvae showed stunted growth decreased egg formation and severe damage of liver. 2. In the experimental infestation of the larvae to normal pigs, as illustrated in table 3, a group with large dose of larvae (a total of 1,800 larvae, 300 larvae Per dose, twice in a dart for 3 days) showed acute clinical syndrome terminatine death with a week course, whereas two groups with less dose of larvae (a total of 180~360 larvae, 10 larvae per dose, at 5 days interval for 70~180 days) showed subclinical syndrome with remarkably stunted growth as. much as approximately one half of body size in contest to the control pigs. In the pathological findings, a group with large dose of larvae showed macroscopically larvae penetrating to the gastric wall with severe gastroenteritis, and histopathologically various acute lesions caused by active larvae penetration into the wall of stomach and interstine, whereas two groups with less dose of larvae showed chronic lesions such as hypertrophy and verminous granulomatous swelling of gastric wall, suggesting strongly the possibility of natural infestation of larvae to swine. 3. In the resistance of the larvae to the chemical solutions, the larvae tolerated for 2 days in 15 percent solution of sodium chloride and acetic acid, and for 7 days in 70 percent solution of ethyl alcohol. In the resistance to the temperature, the larvae died within 1 second at $62^{\circ}C$ and tolerated for 24 hours at $-3^{\circ}C$, 12 hours $-5^{\circ}C$ respectively. 4. For the experiment on the vermicidal effect to larvae, general vermicidal drugs such as Neguvon, Combantrin, antimony Potassium, piperazine adipate and piperazine dihydrochloride, oxidizer such as potassium permanganate and potassium chlorate, and dyes such as gentian violet and crystal violet were used, and among them, as illustrated in table 6, potassium permanganate was proved as the best. In the successive test for the practical use of potassium permanganate, vermicidal effect in seawater solution of potassium permanganate and common-water solution of potassium permanganate were compared, and then retested by dipping the fish viscera including the larvae into the two different solutions of potassium permanganate. The result through these tests indicated that 0.01 percent common water and sea-water solution of potassium permanganate could be apparently recommended as a preventive vermicidal solution, having 90 to 100 percent vermicidal effect by dipping for 12 to 24 hours even though sea-water solution of potassium permanganate had a tendency to slightly less effect than the common-water solution of potassium permanganate (Table 8).

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Alteration of Apurinic/Apyrimidinic Endonuclease-1/Redox Factor-1 in Human Mon-small Cell Lung Cancer (비소세포 폐암조직에시 Apurinic/Apyrimidinic Endonuclease-1/Redox Factor-1의 발현변화)

  • Yoo, Dae-Goon;Song, Yun-Jeong;Cho, Eun-Jung;Kang, Min-Woong;Han, Jong-Hee;Na, Myung-Hoon;Lim, Seung-Pyung;Yu, Jae-Hyeon;Jeon, Byeong-Hwa;Lee, Young
    • Journal of Chest Surgery
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    • v.40 no.8
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    • pp.529-535
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    • 2007
  • Background: An imbalance between oxidants and antioxidants leads to oxidative stress, and this has been proposed to play an important role in the pathogenesis of lung neoplasm. Apurinic/apyrimidinic endonuclease-1/redox factor-1 (APE/ref-1) is a multifunctional protein involved in DNA base excision repair and the redox regulation of many transcription factors. However, the alteration of the expressed levels of APE/ref-1 in non-small cell lung cancer is unknown. Material and Method: Forty-nine patients with surgically resected non-small cell lung cancer (NSCLC) were included in this study. Immunohistochemical staining with APE/ref-1 antibodies was performed, and their expressions were analyzed via Western blotting for specific antibodies. Result: APE/ref-1 was localized at the nucleus and mainly in the non-tumor region of the NSCLC tissue specimens; it was expressed in the cytoplasm and nucleus of the NSCLC. The nuclear and cytoplasmic expressions of APE/ref-1 in lung cancers were markedly up-regulated in the NSCLC, and this was correlated with the clinical stage. Catalase, as first-line antioxidant defense, was dramatically decreased in the NSCLC. Conclusion: Taken together, our results suggest that APE/ref-1, and especially cytoplasmic APE/ref-1, was upregulated in the lung cancer regions, and this may contribute to the compensatory defense system against oxidative stress. A low expression of catalase might have fundamental effects on the extracellular redox state of lung tumors, along with the potential consequences for the tumors.

Development of Porcine Pericardial Heterograft for Clinical Application (Tensile Strength-thickness) (돼지의 심낭을 이용한 이종이식 보철편의 개발 (장력-두께간의 구조적 특성))

  • Kim, Kwan-Chang;Lee, Cheul;Choi, Chang-Hue;Lee, Chang-Ha;Oh, Sam-Sae;Park, Seong-Sik;Kim, Kyung-Hwan;Kim, Woong-Han;Kim, Yong-Jin
    • Journal of Chest Surgery
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    • v.41 no.2
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    • pp.170-176
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    • 2008
  • Background: Bioprosthetic devices for treating cardiovascular diseases and defects may provide alternatives to autologous and homograft tissue. We evaluated the mechanical and physical conditions of a porcine pericardial bioprosthesis treated with Glutaraldehyde (GA), Ethanol, or Sodium dodecylsulfate (SDS) before implantation. Material and Method: 1) Thirty square-shaped pieces of porcine pericardium were fixed in 0.625%, 1.5% or 3% GA solution. 2) The tensile strength and thickness of these and other bioprosthesis, including fresh porcine pericardium, fresh human pericardium, and commercially produced heterografts, were measured. 3) The tensile strength and thickness of the six treated groups (GA-Ethanol, Ethanol-GA, SDS only, SDS-GA, Ethanol-SDS-GA and SDS-Ethanol-GA) were measured. Result: 1) Porcine pericardium fixed in 0.625% GA the thinnest and had the lowest tensile strength, with thickness and tensile strength increasing with the concentration of GA solution. The relationship between tensile strength and thickness of porcine pericardium increased at thicknesses greater than 0.1mm (correlation-coefficient 0.514, 0<0.001). 2) There were no differences in tensile strength or thickness between commercially-produced heterografts. 3) Treatment of GA, ethanol, or SDS minimally influenced thickness and tensile strength of porcine pericardium, except for SDS alone. Conclusion: Porcine pericardial bioprosthesis greater than 0.1 mm thick provide better handling and advantageous tensile strength. GA fixation did not cause physical or mechanical damage during anticalcification or decellularization treatment, but combining SDS-ethanol pre-treatment and GA fixation provided the best tensile strength and thickness.

THE EFFECTS OF SURFACE CONTAMINATION BY HEMOSTATIC AGENTS ON THE SHEAR BOND STRENGTH OF COMPOMER (지혈제 오염이 콤포머의 전단결합강도에 미치는 영향)

  • Heo, Jeong-Moo;Kwak, Ju-Seog;Lee, Hwang;Lee, Su-Jong;Im, Mi-Kyung
    • Restorative Dentistry and Endodontics
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    • v.27 no.2
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    • pp.150-157
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    • 2002
  • One of the latest concepts in bonding are "total etch", in which both enamel and dentin are etched with an acid to remove the smear layers, and "wet dentin" in which the dentin is not dry but left moist before application of the bonding primer Ideally the application of a bonding agent to tooth structure should be insensitive to minor contamination from oral fluids. Clinically, contaminations such as saliva, gingival fluid, blood and handpiece lubricant are often encountered by dentists during cavity preparation. The aim of this study was to evaluate the effect of contamination by hemostatic agents on shear bond strength of compomer restorations. One hundred and ten extracted human maxillary and mandibular molar teeth were collected. The teeth were removed soft tissue remnant and debris and stored in physiologic solution until they were used. Small flat area on dentin of the buccal surface were wet ground serially with 400, 800 and 1200 abrasive papers on automatic polishing machine. The teeth were randomly divided into 11 groups. Each group was conditioned as follows : Group 1: Dentin surface was not etched and not contaminated by hemostatic agents. Group 2: Dentin surface was not etched but was contaminated by Astringedent$^{\circledR}$(Ultradent product Inc., Utah, U.S.A.) Group 3: Dentin surface was not etched but was contaminated by Bosmin$^{\circledR}$(Jeil Pharm, Korea.). Group 4: Dentin surface was not etched but was contaminated by Epri-dent$^{\circledR}$(Epr Industries, NJ, U.S.A.). Group 5: Dentin surface was etched and not contaminated by hemostatic agents. Group 6: Dentin sorface was etched and contaminated by Astringedent$^{\circledR}$. Group 7 : Dentin surface was etched and contaminated by Bosmin$^{\circledR}$. Group 8: Dentin surface was etched and contaminated by Epri-dent$^{\circledR}$. Group 9: Dentin surface was contaminated by Astringedent$^{\circledR}$. The contaminated surface was rinsed by water and dried by compressed air. Group 10: Dentin surface was contaminated by Bosmin$^{\circledR}$. The contaminated surface was rinsed by water and dried by compressed air. Group 11 : Dentin surface was contaminated by Epri-dent$^{\circledR}$. The contaminated surface was rinsed by water and dried by compressed air. After surface conditioning, F2000$^{\circledR}$ was applicated on the conditoned dentin surface The teeth were thermocycled in distilled water at 5$^{\circ}C$ and 55$^{\circ}C$ for 1,000 cycles. The samples were placed on the binder with the bonded compomer-dentin interface parallel to the knife-edge shearing rod of the Universal Testing Machine(Zwick Z020, Zwick Co., Germany) running at a cross head speed or 1.0 mm/min. Group 2 showed significant decrease in shear bond strength compared with group 1 and group 6 showed significant decrease in shear bond strength compared with group 5. There were no significant differences in shear bond strength between group 5 and group 9, 10 and 11.

Computer Aided Diagnosis System for Evaluation of Mechanical Artificial Valve (기계식 인공판막 상태 평가를 위한 컴퓨터 보조진단 시스템)

  • 이혁수
    • Journal of Biomedical Engineering Research
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    • v.25 no.5
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    • pp.421-430
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    • 2004
  • Clinically, it is almost impossible for a physician to distinguish subtle changes of frequency spectrum by using a stethoscope alone especially in the early stage of thrombus formation. Considering that reliability of mechanical valve is paramount because the failure might end up with patient death, early detection of valve thrombus using noninvasive technique is important. Thus the study was designed to provide a tool for early noninvasive detection of valve thrombus by observing shift of frequency spectrum of acoustic signals with computer aid diagnosis system. A thrombus model was constructed on commercialized mechanical valves using polyurethane or silicon. Polyurethane coating was made on the valve surface, and silicon coating on the sewing ring of the valve. To simulate pannus formation, which is fibrous tissue overgrowth obstructing the valve orifice, the degree of silicone coating on the sewing ring varied from 20%, 40%, 60% of orifice obstruction. In experiment system, acoustic signals from the valve were measured using microphone and amplifier. The microphone was attached to a coupler to remove environmental noise. Acoustic signals were sampled by an AID converter, frequency spectrum was obtained by the algorithm of spectral analysis. To quantitatively distinguish the frequency peak of the normal valve from that of the thrombosed valves, analysis using a neural network was employed. A return map was applied to evaluate continuous monitoring of valve motion cycle. The in-vivo data also obtained from animals with mechanical valves in circulatory devices as well as patients with mechanical valve replacement for 1 year or longer before. Each spectrum wave showed a primary and secondary peak. The secondary peak showed changes according to the thrombus model. In the mock as well as the animal study, both spectral analysis and 3-layer neural network could differentiate the normal valves from thrombosed valves. In the human study, one of 10 patients showed shift of frequency spectrum, however the presence of valve thrombus was yet to be determined. Conclusively, acoustic signal measurement can be of suggestive as a noninvasive diagnostic tool in early detection of mechanical valve thrombosis.