• Title/Summary/Keyword: Stability Examination

Search Result 333, Processing Time 0.03 seconds

Practical Application of Dioscorea quinqueloba Extract for the Control of Citrus Green Mold (감귤 녹색곰팡이병 방제를 위한 천산용 추출물의 실용적 적용)

  • Lee, Ji Hyun;Kang, Sung Woo;Song, Jeong Young;Kim, Hong Gi
    • Research in Plant Disease
    • /
    • v.18 no.4
    • /
    • pp.354-360
    • /
    • 2012
  • This study tested the antifungal compound obtained from a medicinal plant, Dioscorea quinqueloba Thunb., in order to search the possibility of practical application of this product in agriculture through evaluating its activity using the citrus fruits. The extract of D. quinqueloba Thunb., which has the strongest antifungal activity, was selected as a candidate among 101 plant extracts. Based on this examination concerning antifungal activity of the product on Penicillium digitatum in vitro, it was confirmed its effect of mycelial growth inhibition showed over 87% at 0.5 mg/ml concentration. This natural product showed the stability of the substance, as it was not significantly influenced by pH, temperature, or ultraviolet radiation. While citrus fruits were stored at room temperature, P. digitatum was inoculated into them in order to prepare a similar environmental conditions with epidemic occurrence of the mold. As the result of our investigation, the disease preventive effects of the active antifungal substance evidenced a 100% at 0.5 mg/ml. When the phytotoxicity of the selected natural product on citrus at 2 mg/ml was assessed, we noted no toxic effects. Based on the superior preventive effects from this natural product extracted from the plant, it is presumed to be very useful in agricultural applications for the control of green mold, P. digitatum, which has been occurred often the biggest problem in the storage of citrus fruits.

A Study on the Effect and Mechanism of Gamikyejakjimogawusul-tang Herbal Acupuncture on Induced Rheumatoid Arthritis model of DBA/1 mice (계작지모가우슬탕(桂芍知母加牛膝湯) 약침이 류마티스 관절염 생쥐에 미치는 영향)

  • Jung, Soon Hyun;Cho, Chong kwan;Kim, So Yun;Kim, Young Il
    • Journal of Haehwa Medicine
    • /
    • v.24 no.2
    • /
    • pp.35-57
    • /
    • 2016
  • Objectives : The purpose of this study is to prove the effect and mechanism of Gamikyejakjimogawusul-tang(GKHA) herbal acupuncture on induced rheumatoid arthritis model of DBA/1 mice. Methods : We check effect of GKHA extract on the AST, ALT, Creatinine, BUN of serum and cell viability of GK extract in RAW 264.7 cells to test the stability of this study. In vitro, we measure total phenol contents, total flavonoid contents, DPPH free radical scavenging activity, ABTS cation radical scavenging activity of Gamikyejakjimogawusul-tang, effect of GK extract on ROS(Reactive Ooxygen Species) production to estimate a anti-oxidant capacity, and we also measure effect of GK extract on NO (Nitric Oxid), IL-$1{\beta}$, IL-6, IL-17, IL-21, TNF-${\alpha}$, MCP-1, GM-CSF production in RAW 264.7 cells to estimate a anti-inflammatory efficacy. In vivo, we compare a rheumatoid arthritis manifestation between control and experimental group and estimate a AI. Then we check effect of GKHA on the level of WBC, neutrophil, lympocyte, monocyte in the blood to see the effect of immune cells in blood. In addition we measure effect of GKHA on the level of hs-CRP, IgM, IgG, IL-$1{\beta}$, IL-6, IL-17, IL-21, TNF-${\alpha}$, MCP-1, GM-CSF in serum. We observe effects of GKHA on imaging of cartilage degeneration using micro CT-arthrography in paw hind. And we calculate effects of GKHA that reduced BV ratio, BS/BV ratio using 3D Micro-CT. Lastly we observe effects of GKHA histopathologic examination analysis. Results : 1. The toxicity on liver and kidney was disregardable and the cytotoxicity against RAW 264.7 cells was also disregardable. 1. Total phenol contents and total flavonoid contents in GK extract were in high level. 2. DPPH free radical scavenging activity and ABTS cation radical scavenging activity were increased according to concentration of GK extract 3. ROS production was significantly decreased in GK extract (at 10, $100{\mu}g/ml$). 4. NO, IL-6, TNF-${\alpha}$, MCP-1 production were significantly decreased in GK extract(at 10, $100{\mu}g/ml$). IL-17, GM-CSF production were significantly decreased in GK extract(at 1, 10, $100{\mu}g/ml$). IL-$1{\beta}$, IL-21 production were also decreased but there was no statistical significance. 5. 25x observation after H&E and M-T staining, infiltration of immune cells and subsidence of the cartilage and damage to the synovial cells were decreased. Conclusions : This study showed that GKHA extract had anti-oxidant capacity, anti-inflammatory efficacy. GKHA extract also had inhibiting effect on the process of rheumatoid arthritis and can protect joint and cartilage. So we expect that GKHA extract can be a meaningful treatment to rheumatoid arthritis patients.

APPLICATION OF CAD/CAM FOR ORAL REHABILITATION IN A PATIENT WITH DOWN SYNDROME (CAD/CAM을 이용한 다운 증후군 환자의 구강 재건)

  • Chung, Hyunjin;Shim, Joon-Sung;Choi, Byung-Jai;Lee, Jae-Ho
    • The Journal of Korea Assosiation for Disability and Oral Health
    • /
    • v.13 no.2
    • /
    • pp.95-98
    • /
    • 2017
  • Due to hypodontia, poor oral hygiene, and significantly more prevalent periodontal disease, patients with Down syndrome show higher incidence of edentulism. Oral rehabilitation of such patients is imperative but challenging as high rates of prosthesis failure are reported due to malocclusion, high masticatory force, and parafunctional habits. As CAD/CAM(Computer-Aided Design and Computer Aided Manufacturing) is the recent trend in prosthodontics, this report discusses the application of CAD/CAM in a Down syndrome patient. A 25-year-old patient with Down syndrome was presented to the Department of Pediatric Dentistry, Yonsei University Dental Hospital for oral examination. 5 maxillary teeth were missing, 3 were fully impacted, and 4 had grade III mobility. The patient underwent general anesthesia for extraction of impacted and mobile teeth, implant surgery, and final impression for prosthesis. Afterwards, CAD/CAM was used to design and manufacture a 10-unit zirconia bridge. However the bridge was fractured after 18 months due to the patient's bruxism and high masticatory force. Final impression taking, bite registration, cast fabrication, cast scanning, and prosthesis designing were not needed as CAD/CAM data remained. Previous CAD/CAM design was used to remanufacture the zirconia bridge. Down syndrome patients have malocclusion, high masticatory force, and parafunctional habits which increase the possibility of prosthesis fracture. CAD/CAM is beneficial for Down syndrome patients as previous digital records can be utilized for prosthesis repair or remake. In detail, application of CAD/CAM in remanufacturing decreases patient's discomfort of impression taking, shortens and simplifies dental laboratory procedures, and reduces clinician's effort of taking detailed final impressions or accurate bite registration. In conclusion, oral rehabilitation using CAD/CAM provides not only satisfactory levels of comfort, stability, and esthetics, but also easier repair or remake compared to conventional prostheses.

AN EXPERIMENTAL STUDY ON THE OSSEOINTEGRATION OF THE TI-6AL-4V BEAD COATING IMPLANTS (Ti-6Al-4V 비드코팅 임프란트 시제품의 골유착에 대한 실험적 연구)

  • Woo, Jin-Oh;Park, Bong-Wook;Byun, June-Ho;Kim, Seung-Eon;Kim, Gyoo-Cheon;Park, Bong-Soo;Kim, Jong-Ryoul
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.30 no.1
    • /
    • pp.52-59
    • /
    • 2008
  • The geometric design of an implant surface may play an important role in affecting early osseointegration. It is well known that the porous surfaced implant had much benefits for the osseointegration and the early stability of implant. However, the porous surfaced implant had weakness from the transgingival contamitants, and it resulted in alveolar bone loss. The other problem identified with porous surface implant is the loss of physical properties resulting from the bead sintering process. In this study, we developed the new bead coating implant to overcome the disadvantages of porous surfaced implant. Ti-6Al-4V beads were supplied from STARMET (USA). The beads were prepared by a plasma rotating electrode process (PREP) and had a nearly spherical shape with a diameter of 75-150 ${\mu}m$. Two types of titanium implants were supplied by KJ Meditech (Korea). One is an external hexa system (External type) and the other is an internal system with threads (Internal type). The implants were pasted with beads using polyvinylalcohol solution as a binder, and then sintered at 1250 $^{\circ}C$ for 2 hours in vacuum of $10^{-5}$ torr. The resulting porous structure was 400-500 ${\mu}m$ thick and consisted of three to four bead layers bonded to each other and the implant. The pore size was in the range of 50-150 ${\mu}m$ and the porosity was 30-40 % in volume. The aim of this study was to evaluate the osseointegration of the newly developed dental implant. The experimental implants (n=16) were inserted in the unilateral femur of 4 mongrel dogs. All animals were killed at 8 weeks after implantation, and samples were harvested for hitological examination. All bead coated porous implants were successfully osseointegrated with peripheral bone. The average bone-implant contact ratios were 84.6 % (External type) and 81.5 % (Internal type). In the modified Goldner's trichrome staining, new generated mature bones were observed at the implant interface at 8 weeks after implantation. Although, further studies are required, we could conclude that the newly developed vacuum sintered Ti-6Al-4V bead coating implant was strong enough to resist the implant insertion force, and it was easily osseointegrated with peripheral bone.

Properties of Bubble According to Types and Concentrations of Concrete Foaming Agent (콘크리트용 기포제 종류 및 농도에 따른 기포의 특성)

  • Kim, Jin-Man;Kwak, Eun-Gu;Oh, Kwang-Chin;Kang, Cheol
    • Journal of the Korea Concrete Institute
    • /
    • v.23 no.2
    • /
    • pp.151-158
    • /
    • 2011
  • Bubbles within the foamed concrete manufactured by pre-foaming method is the main factor which affects the physical properties of foamed concrete such as density, strength, and porosity. Although many researches on foamed concrete have been continuously carried out, insufficient number of researches on the properties related to bubbles in the foamed concrete has been performed except for chemical application related researches. In order to make an optimal foamed concrete, study on the bubble properties must be pursued. In order to effectively implement bubbles in the manufacturing of foamed concrete, the bubble properties must be estimated. In this study, in order to determine the bubble properties, examination of the bubble properties according to types and foaming agent concentration was performed. An foaming agent used for this test were anionic surfactant, rosin, and protein system with the foaming agent concentration range of 0.05~13%. Test parameters considered in the study were foaming rate, foam volume, drainage solution volume, and bubble size. The study results showed that, regardless of foaming agent type, higher concentration of foaming agent showed an increase in the foaming rate. Also, the results showed that concentration of foaming agent affected bubble size, drainage solution volume change, and bubble distributions. With respect to the stability of the bubble, protein foaming agent was better than anion surfactant or rosin foaming agent. With respect to the bubble shape, anion surfactant and rosin formed bubbles had polygon shape where as protein formed bubbles had spherical shape.

Studies on the Preparation of $^{99m}TC$ Labelled Antimony Sulfide Colloid and Hydroxyethyl Starch for Lymphoscintigraphy (림포신티그래피용 $^{99m}TC$를 표지황화안티몬 콜로이드 및 전분의 제조에 관한 연구)

  • Park, Kyung-Bae;Awh, Ok-Doo;Kim, Jae-Rok;Lim, Sang-Moo;Hong, Seong-Woon
    • The Korean Journal of Nuclear Medicine
    • /
    • v.23 no.1
    • /
    • pp.71-83
    • /
    • 1989
  • For the development of $^{99m}Tc-labelled$ antimony sulfide colloid and hydroxyethyl starch, various experiments such as preparation of colloid, control of the distribution of particle size, establishment of labelling conditions, determination of labelling yield and radiochemical purity, examination of stability, and organ imagings of rabbits etc. were carried out. 1) Antimony sulfide colloid was readily prepared by the reaction of aqueous solution of antimony potassium tartrate with hydrogen sulfide generated by treating ferrous sulfide with dilute sulfuric acid. The colloid could be stabilized by adding small amount of polyvinylpyrrolidone. 2) Electron microscopy analysis exhibited the distribution of colloid size in the range of $1\sim15nm$ with a major portion of 9 m. The colloid solution was sterilized by membrane filtration $(0.2{\mu}m)$ and then stored at $4^{\circ}C$. This sterilized colloid was so stable that it was usable at least for one year. 3) The antimony sulfide colloid was labelled by adding sodium $pertechnetate-^{99m}Tc$ solution to the reaction vial, followed by adding hydrochloric acid and then boiled for 30 min. The optimal pH of the reaction mixture was found to be in the range of $1.3\sim1.4$. Instant thin layer chromatography (ITLC) analysis showed high labelling yield of above 99.5%. This labelled colloid maintained high radio-chemical purity of above 99% until 10 hours after labelling. 4) Animal studies showed high uptake of $^{99m}Tc-Sb_2S_3$ colloid at lymph vessels and nodes indicating a suitable agent for lymphoscintigraphy. Satisfactory results were also abtained in other clinical studies. 5) Hydroxyethyl starch (HES $0.6\sim1.0%$) was labelled with $Na^{99m}TcO_4$ in the presence of $SnCl_2$ with high labelling yield of above 99.5%. The optimal pH of the reaction mixture was in the range of $1.8\sim2.0$. $^{99m}Tc-HES$ maintained high radiochemical purity of above 99% until 10 hours after labelling. 6) Animal studies showed that $^{99m}Tc-HES$ migrated more rapidly from the injection sites into the lymph vessels than $^{99m}Tc-Sb_2S_3$ colloid while less amount of the former was uptaken at lymph nodes than that of the latter. Similar phenomenon was also observed in other clinical studies. As a result, $^{99m}Tc-Sb_2S_3$ colloid was found to be more effective lymphoscintigraphic agent than $^{99m}Tc-HES$.

  • PDF

The Changes of Sweating Area, Temperature and Blood Flow in the Upper and Lower Extremity after Hyperhidrosis Operations (다한증수술후 발한분포 및 상하지의 온도변화와 혈류량변화)

  • 김용환;장윤희;문석환;조건현;왕영필;김세화;곽문섭;김학희;장혜숙
    • Journal of Chest Surgery
    • /
    • v.32 no.5
    • /
    • pp.456-460
    • /
    • 1999
  • Background: Thoracic sympathectomy for hyperhidrosis has been recognized as an effective treatment using thoracoscopic devices and operative techniques, but the satisfaction has decreased due to a compensatory hyperhidrosis. Therefore, the postoperative results and compensatory hyperhidrosis were analyzed. We also measured the temperature differences in the hand and foot during the preoperative and postoperative periods and measured the blood flow of upper and lower extremities. Material and Method: From December 1995 to July 1998, total of 47 patients with hyperhidrosis underwent sympathectomy via VATS at the Department of Thoracic and Cardiovascular Surgery, Kangnam St. Mary's Hospital. The patients were evaluated for preoperative and postoperative temperature changes on the finger and toe, and preoperative and postoperative blood flows were measured by the Doppler examination on the digital artery, radial artery and dorsalis pedis artery. Result: There were no operative deaths but some complications existed: 7 pneumothorax, 3 recurrence and 1 Honor syndrome. Ninety-five percent of the patients also had compensatory sweating especially in the trunk. There were 5 patients who regretted recurring the operation because of the compensatory sweating. Sweating decreased in 46% of the sole hyperhidrosis patients. The temperature difference between preoperation and postoperation was 1$^{\circ}C$ on the right hand side and 1.9$^{\circ}C$ on the left hand side(P<0.05). There was no significant temperature difference on the sole. Blood flow increased significantly in the palm, but no difference in the sole. Conclusion: In conclusion, thoracic sympathectomy for hyperhidrosis is a safe and effective treatment but satisfaction has been decreased by the compensatory sweating; therefore, it is important to thoroughly explain the compensatory sweating prior to surgery. Improvement of the plantar hyperhidrosis is not due to a physiological change, but to a psychological stability.

  • PDF

New Modified Chevron Osteotomy for Hallux Valgus (무지 외반증의 새로운 변형 Chevron 절골술)

  • Oh, In-Suk;Kim, Myung-Ku;Choi, Sung-Wook;Ban, Jun-Ho
    • Journal of Korean Foot and Ankle Society
    • /
    • v.8 no.2
    • /
    • pp.126-130
    • /
    • 2004
  • Purpose: In this study, we tried to develop the technique of osteotomy for hallux valgus. The new modified technique of osteotomy was accomplished with even more greater stability, accurate correction of the deformity and more effective than 'chevron' osteotomy in terms of correction of the deformity. Materials and Methods: Between March 1998 and December 2001, 55 cases of new modified osteotomy for hallux valgus were performed for 39 patients, 16 of whom underwent operation of both feet. Operations were made for 34 women and 5 men whose average age was 46 years old (range, $20{\sim}71$ years). Average follow up period was three years (range, $2{\sim}5$ years), and during the follow up, the patients underwent physical examination and assessment with use of the American Orthpaedic Foot and Ankle Society's hallux-metatarso-phalangealinterphalangeal scale and standard foot radiographic measurements. Results: 37 patients (53 cases) out of 39 patients (55 cases) had no pain, good cosmesis, and all of the patients were satisfied with the results of the operation. Two had occasional mild discomfort. The average score according to the hallux-metatarso-phallangeal-interphalangeal scale was 93.2 points (range, $78{\sim}100$ points). The average preoperative intermetatarsal angle was $14.4^{\circ}$, which was decreased to $7.9^{\circ}$ after the osteotomy with an average correction of $6.5^{\circ}$ and The average preoperative hallux valgus angle was $34.1^{\circ}$, which was decreased to $11.1^{\circ}$ after the osteotomy with an average correction of $23^{\circ}$. This new modified technique would prevent the angulation or shortening at the osteotomy site and it was also even more stable at osteotomy site, and could do even more effective and accurate correction of the deformity than conventional Chevron osteotomy. Conclusion: New modified chevron osteotomy for the treatment of symptomatic hallux valgus was done in 55 cases, and the results were satisfactory in all cases. This method was more stable at the osteotomy site than conventional Chevron osteotomy and was also possible to do more accurate and more effective correction of the deformity. It was also easy to control the distal fragment of first metatarsal bone.

  • PDF

Scientific Conservation Treatment of the Celadon Jar with the Inscription of 'the Fourth Sunhwa Year'(National Treasure No.326) (국보 제326호 청자 '순화4년'명 항아리의 과학적 보존처리)

  • Lee, Sun Myung;Kwon, Oh Young;Park, Jongseo;Han, Woo Rim
    • Journal of Conservation Science
    • /
    • v.35 no.5
    • /
    • pp.453-469
    • /
    • 2019
  • The celadon jar with inscription of 'the Fourth Sunhwa Year' is an important chronology that shows the conditions of production of the early celadon due to the inscription on the bottom including its purpose, application, and the producer. This celadon jar has been restored several times in the past. However, concerns over the structural stability, such as the separation and level differences in the joined cracks, have risen because of the aging of the repair materials, which were subjected to various environmental changes over a long time. By examining the conditions of preservation, the major damage was identified as the '入' shaped crack on the front, the 'V' shaped restored part and the crack on its left side, and the 'J' shaped crack on the back side. In the past, the cracks were found to be joined using a refined lacquer containing camphor, drying oil, rosin, etc. mixed with soil powder. The joint line was repainted with the refined lacquer and covered with gold powder. The missing parts were restored with gypsum and colored with acrylic color. After that, the repair materials were aged and emergency treatment was performed at the National Museum of Korea in 1981. At that time, Cemedine C or Cemedine C mixed with microballoons was used for reinforcing the cracks. Conservation treatment focused on removing the past repair materials and reinforcing the physically fragile parts by joining and restoring them based on the examination of the preservation condition. in addition, the area around the restored part was colored for future exhibition.

Examination of GC-TD sensitivity for reduced sulfur compounds in relation to temporal stability and reproducibility (환원 황화합물의 열탈착 분석기법에 대한 감도의 경시변화 및 재현성에 대한 연구)

  • Hong, One-Feel;Kim, Ki-Hyun
    • Analytical Science and Technology
    • /
    • v.23 no.1
    • /
    • pp.24-35
    • /
    • 2010
  • To learn more about the calibration properties of reduced sulfur compounds (RSCs) by the combination of gas chromatography(GC)-pulsed flame photometric detector (PFPD) and thermal desorption method, a series of calibration experiments were conducted on the basis of both internal and external calibration approaches. For these experiments, gaseous standards of 4 RSCs ($H_2S$, $CH_3SH$, DMS, and DMDS) were prepared at two different concentration levels of both low (10, 20, 50,and 100 ppb) and high ranges (100, 200, 500, and 1000 ppb) along with $CS_2$ as an internal standard. First, the external calibration results were compared between fixed standard volume (FSV) and fixed standard concentration (FSC) method. Secondly, FSV-based calibration results were compared between external and internal calibration results. As FSV method suffers from sensitivity variations less significantly than FSC, the former is recommended to maintain the consistency in GC-TD sensitivity for RSC analysis. In addition, when the calibration data were examined in terms of RSE between external and internal calibration data, the results were not consistent enough to show improvements in internal method. Hence, diverse efforts are desirable to optimize the reproducibility in terms of GC-TD sensitivity for RSC analysis.