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Endodontic treatment of mandibular molar with root dilaceration using Reciproc single-file system

  • Meireles, Daniely Amorin;Bastos, Mariana Mena Barreto;Marques, Andre Augusto Franco;Garcia, Lucas Da Fonseca Roberti;Sponchiado, Emilio Carlos Junior
    • Restorative Dentistry and Endodontics
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    • v.38 no.3
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    • pp.167-171
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    • 2013
  • Biomechanical preparation of root canals with accentuated curvature is challenging. New rotatory systems, such as Reciproc, require a shorter period of time to prepare curved canals, and became a viable alternative for endodontic treatment of teeth with root dilaceration. Thus, this study aimed to report a clinical case of endodontic therapy of root with accentuated dilaceration using Reciproc single-file system. Mandibular right second molar was diagnosed as asymptomatic irreversible pulpitis. Pulp chamber access was performed, and glide path was created with #10 K-file (Dentsply Maillefer) and PathFile #13, #16 and #19 (Dentsply Maillefer) up to the temporary working length. The working length measured corresponded to 20 mm in the mesio-buccal and mesio-lingual canals, and 22 mm in the distal canal. The R25 file (VDW GmbH) was used in all the canals for instrumentation and final preparation, followed by filling with Reciproc gutta-percha cones (VDW GmbH) and AH Plus sealer (Dentsply Maillefer), using thermal compaction technique. The case has been receiving follow-up for 6 mon and no painful symptomatology or periapical lesions have been found. Despite the difficulties, the treatment could be performed in a shorter period of time than the conventional methods.

Anti-nociceptive Effects of Clerodendrum Trichotomum (누리장나무의 진통 효과)

  • Kyoung Ro Chung;Byung Soo Lee;Myung Soo Kim;Hee Jae Goh;Woo In Yang;Yong Deok Jeon;Ji-Hye Ahn;Dong Seok Cha;Jin Kwon;Hoon Jeon
    • Korean Journal of Pharmacognosy
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    • v.54 no.2
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    • pp.61-65
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    • 2023
  • Clerodendrum trichotomum has been widely used as a traditional medicine for the treatment of numerous diseases, including pain management. However, there have been extremely limited pharmacological and phytochemical studies on Clerodendrum trichotomum up to now. In this study, we investigated the effects of the methanolic extract of Clerodendrum trichotomum (MCT) on nociceptive pain in mice. Our finding demonstrate that MCT treatment significantly extended the latency time in both the tail-immersion test and hot-plate test. Additionally, MCT treatment reduced acetic acid-induced writhing motions. These results suggest that MCT possesses strong anti-nociceptive activities against thermal and chemical nociception. In the formalin test, mice fed with MCT exhibited reduced licking time during both the early and late phases, thereby confirming the therapeutic potential of MCT in central and peripheral nociception. Furthermore, in combination tests using naloxone, the MCT-mediated anti-nociception was slightly reduced, indicating that MCT might act as a partial opioid receptor agonist. Based on these results, MCT may be a valuable candidate for the development of anti-nociceptive agents.

Effect of Sterilization by Intense Pulsed Light on Radiation-resistant Bacterium, Micrococcus roseus (방사선 저항세균 Micrococcus roseus의 광펄스 살균 효과)

  • Kim, Bora;Kim, Ae-Jin;Shin, Jung-Kue
    • Korean Journal of Food Science and Technology
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    • v.45 no.2
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    • pp.248-251
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    • 2013
  • The purpose of this study was to investigate the inactivation effect of intense pulsed light (IPL) on Micrococcus roseus, an irradiation-resistant bacterium isolated from laver, and the commercial feasibility of this sterilization method on dried laver. The inactivation of M. roseus in cultivated plates increased with increasing light intensity and treatment time. Approximately 6.6 log CFU/mL reduction of the cell viability was achieved with IPL treatment for 3 min at 1,000 V of light intensity, tailing was not shown. In addition, the inactivation rate of M. roseus increased with increasing pulse number at same light intensity and treatment time. The killing efficiency for M. roseus increased with by decreasing the distance between the light source and the sample surface.

Characteristics of perovskite-structure Sr(Ti1-xFex)O3 thick film gas sensors (페롭스카이트 구조 Sr(Ti1-xFex)O3 후막 가스센서의 특성)

  • Jin, Guang-Hu;Lee, Woon-Young;Lee, Hyun-Gyu;Park, Jin-Seong
    • Journal of Sensor Science and Technology
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    • v.18 no.6
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    • pp.456-461
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    • 2009
  • Perovskite-structure $Sr(Ti_{1-x}Fe_x)O_3$ thick films, in which x is 0.4 or 0.6, were prepared by normal ceramic process on alumina substrate. Electrical resistance was measured as a function of thermal treatment condition including atmosphere, time, and temperature. The resistance of $Sr(Ti_{1-x}Fe_x)O_3$ films is lower than those of $SrTiO_3$ or $SrFeO_3$ films. The temperature coefficient of resistance over $550^{\circ}C$ was measured to be 0 for the $Sr(Ti_{1-x}Fe_x)O_3$ films after thermal treatment at $1100^{\circ}C$ in air. The sensing property of the films was also measured as a function of temperature and gas such as $O_2$, CO, $CO_2$, NO and $NO_2$. $Sr(Ti_{1-x}Fe_x)O_3$ films showed a good sensing property for $O_2$, but no sensing signal for CO, $CO_2$, NO and $NO_2$.

Effect of the Calcium Nitrate Solution Treatment on the Tensile, Bending, and Shear Properties of Silk Fabric

  • Park, Su-Zin;Kang, Ji-Young;Seol, Da-Won;Yang, Hye-Min;Lee, Ji-Min;Ahn, Ye-Ji;Han, Seo-Young;Kim, Jong-Jun
    • Journal of Fashion Business
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    • v.14 no.6
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    • pp.39-52
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    • 2010
  • Interests in creating three-dimensionally designed fabric materials are growing rapidly in the sectors of the fashionable textiles with the creativity, new functions, and aesthetics. A number of finishing methods have been developed and proposed to add or create new functions and designs for silk fabrics. Due to the strong hydrogen bonds between the molecules of silk fibroins, the thermal treatment methods used in thermoplastic fiber processing, which can easily deform the synthetic filament fabrics to endow three-dimensional appearance to the fabrics, are not applicable to the silk fabric treatment. In order to modify the fine structure of silk fiber, neutral salt solution treatment methods have been suggested. In this study, the effect of the calcium nitrate solution on the physical and mechanical properties of silk fabrics was investigated by using the KES(Kawabata Evaluation System) equipment. Based on these findings, relationships between parameters, for example, the thickness and the compressional energy, the thickness and the compressional linearity, and the air permeability and the pore area statistical analysis were investigated. The relationships between the process parameters such as treatment temperature/time and the resulting fabric property parameters were also analyzed by using several SAS procedures.

Quality Changes and Pasteurization Effects of Citrus Fruit Juice by High Voltage Pulsed Electric Fields (PEF) treatment (고전압 펄스 전기장 처리에 의한 감귤주스의 품질변화)

  • Kim, Kyung-Tack;Kim, Sung-Soo;Hong, Hee-Do;Ha, Sang-Do;Lee, Young-Chun
    • Korean Journal of Food Science and Technology
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    • v.35 no.4
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    • pp.635-641
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    • 2003
  • A non-thermal pasteurization technology, high Pulsed Electric Field (PEF) has been thought to be a new alternative processing technology instead of heating. The objective of this study was to examine and compare the effect of PEF and High Temperature Short Time (HTST) treatments on the physicochemical, microbiological and sensory characteristics of citrus juices. Total sugar and titratable acidity values of fresh citrus juice and two treatments were not significantly different each other at p<0.05. The concentration of vitamin C in fresh citrus juice $(31.2{\pm}0.59\;mg%)$ was not significantly different with the value of PEF treatment $(29.4{\pm}0.75\;mg%)$ but was significantly higher than the value of HTST treatment $(27.4{\pm}0.75\;mg%)$. The color values (L, a, and b) in PEF treatment were significantly lower than the fresh citrus juice, but were higher than the values of HTST treatment. Both total bacterial cell counts $(6.65\;{\pm}\;0.08\;log_{10}(cfu/mL))$ and yeast counts $(7.79{\pm}0.07\;log_{10}(cfu/mL))$ in fresh citrus juice were significantly reduced by PEF $(1.39{\pm}0.14,\;2.42{\pm}0.1\;log_{10}(cfu/mL))$ as well as HTST treatment (0, 0). PE activity of fresh citrus juice $(1.3{\pm}0.12\;units/mL)$ was significantly reduced by PEF treatment $(0.11{\pm}0.01\;units/mL)$ and was totally inactivated by HTST treatment. Sensory evaluation scores in flavor, taste and overall acceptability between the fresh and PEF treated citrus juices $(7.2{\sim}7.5)$ were not significantly different but the values of HTST treatment $(5.1{\sim}5.8)$ were lower than others. Consequently, PEF treatment is thought to be a good alternative pasteurization method for fresh citrus juice to HTST treatment due to its strong pasteurization effect, reduced destruction of nutrients and good sensory characteristics.

Acid Hydrolysis of Insoluble Sericin (불용성 세리신의 산 가수분해)

  • Kim, Jeong-Ho;Bae, Do-Gyu
    • Journal of Sericultural and Entomological Science
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    • v.41 no.1
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    • pp.48-53
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    • 1999
  • The study was carried out to investigate the effects of hydrolysis conditions such as treatment times and concentrations on the solubility of insoluble sericin using the hydrochloric acid solution. When insoluble sericin was hydrolyzed by HCl solution, the solubility was increased with the higher treatment concentration. As the results of electrophoresis of sericin powder obtained by the HCl treatment, a distinguishable band was not confirmed. Average degree of polymerizations(A.D.P.) of sericin hydrolyzed by HCl solution were about 4.2~5.9 and average molecular weights(M.W.) were about 470~670. The longer hydrolysis time reduced the whiteness of sericin powder. As the results of amino acid analysis, the amino acid compositions of the sericin powder from HCl treatment were sililar to that of insoluble sericin, but Tyr. and Arg. were not detected in the powder obtained by HCl treatment. In DSC analysis, thermal deformation and pyrolysis peak located at near 220$^{\circ}C$ and 330$^{\circ}C$.

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Interfacial Evaluation of Plasma-Treated Biodegradable Poly(p-dioxanone) Fiber/Poly(L-lactide) Composites Using Micromechanical Technique and Dynamic Contact Angle Measurement (Micromechanical 시험법과 동적접촉각 측정을 이용한 플라즈마 처리된 생분해성 Poly(p-dioxanone) 섬유강화 Poly(L-lactide) 복합재료의 계면물성 평가)

  • Park, Joung-Man;Kim, Dae-Sik;Kim, Sung-Ryong
    • Journal of Adhesion and Interface
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    • v.4 no.1
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    • pp.18-27
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    • 2003
  • Interfacial properties and microfailure degradation mechanisms of the oxygen-plasma treated biodegradable poly(p-dioxanone) (PPDO) fiber/poly(L-lactide) (PLLA)composites were investigated for the orthopedic applications as implant materials using micromechanical technique and surface wettability measurement. PPDO fiber reinforced PLLA composite can provide good mechanical performance for long hydrolysis time. The degree of degradation for PPDO fiber and PLLA matrix was measured by thermal analysis and optical observation. IFSS and work of adhesion, $W_a$ between PPDO fiber and PLLA matrix showed the maximum at the plasma treatment time, at 60 seconds. Work of adhesion was lineally proportional to the IFSS. PPDO fiber showed ductile microfailure modes at We initial state, whereas brittle microfailure modes appeared with elapsing hydrolysis time. Interfacial properties and microfailure degradation mechanisms can be important factors to control bioabsorbable composites performance because IFSS changes with hydrolytic degradation.

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Sterilization and quality variation of dried red pepper by atmospheric pressure dielectric barrier discharge plasma (대기압 유전체장벽방전 플라즈마에 의한 건고추의 식중독균 살균효과 및 품질변화)

  • Song, Yoon Seok;Park, Yu Ri;Ryu, Seung Min;Jeon, Hyeong Won;Eom, Sang Heum;Lee, Seung Je
    • Food Science and Preservation
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    • v.23 no.7
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    • pp.960-966
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    • 2016
  • This study was conducted to explore the potential for use of atmospheric pressure dielectric barrier discharge plasma (atmospheric pressure DBD plasma) as a non-thermal sterilization technology for microorganisms in dried red pepper. The effects of key parameters such as power, exposure time and distance on the sterilization efficiency and the quality of red dried pepper by the atmospheric pressure DBD plasma treatment were investigated. The results revealed that the plasma treatment was very effective for sterilization of Staphylococcus aureus, with 15 min of treatment at 1.0 kW and 20 mm sterilizing 82.6% of the S. aureus. Increasing the power or exposure time and decreasing the exposure distance led to improved sterilization efficiency. The atmospheric pressure DBD plasma treatment showed no effect on the ASTA (American spice trade association) value or hardness of dried red pepper. Furthermore, no effects of atmospheric pressure DBD plasma treatment were observed on the sensory properties of dried red pepper. To assess the storage stability, the dried red pepper was treated with atmospheric pressure DBD plasma (1.5 kW power, 15 min exposure time and 10 mm exposure distance), then stored for 12 weeks at $25^{\circ}C$. Consequently, the ASTA value, hardness and capsaicin concentration of dried red pepper were maintained.

Sterilization of Food-Borne Pathogenic Bacteria by Atmospheric Pressure Dielectric Barrier Discharge Plasma (대기압 유전체장벽방전 플라즈마에 의한 식품유해 미생물 살균)

  • Lee, Seung Je;Song, Yoon Seok;Park, Yu Ri;Ryu, Seung Min;Jeon, Hyeong Won;Eom, Sang Heum
    • Journal of Food Hygiene and Safety
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    • v.32 no.3
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    • pp.222-227
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    • 2017
  • This study aimed to explore the potential for food-industry application of atmospheric pressure dielectric barrier discharge plasma (atmospheric pressure DBD plasma) as a non-thermal sterilization technology for microorganism. The effects of the key parameters such as power, oxygen ratio, exposure time and distance on Escherichia coli KCCM 21052 sterilization by the atmospheric pressure DBD plasma treatment were investigated. The experimental results revealed that increasing the power, exposure time or oxygen ratio and decreasing the exposure distance led to an improvement in the sterilization efficiency of E. coli. Furthermore, the atmospheric pressure DBD plasma (1.0 kW power, 1.0% (v/v) $O_2$, 5 min exposure time and 20 mm exposure distance) treatment was very effective for the sterilization of food-borne pathogenic bacteria. The sterilization rate of E. coli, Bacillus cereus KCCM 40935, Bacillus subtilis KCCM 12027, Bacillus thuringiensis KCCM 11429 and Bacillus atrophaeus KCCM 11314 were 72.3%, 74.6%, 88.5%, 84.7% and 91.3%, respectively.