• Title/Summary/Keyword: Secondary damage

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Experimental Study on Combined Failure Damage of Bi-directional Prestressed Concrete Panel under Impact-Fire Loading (충돌 후 화재에 대한 이방향 프리스트레스트 콘크리트 패널부재의 복합 파괴손상에 관한 실험적 연구)

  • Yi, Na-Hyun;Lee, Sang-Won;Choi, Seung-Jai;Kim, Jang-Ho Jay
    • Journal of the Korea Concrete Institute
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    • v.26 no.4
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    • pp.429-440
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    • 2014
  • Since the World Trade Center and Pentagon attacks in 2001, terror, military attack, or man-made disaster caused impact, explosion, and fire accident have frequently occured on civil infrastructures. However, structural behavior researches on major Prestressed Concrete (PSC) infrastructures such as bridges, tunnels, Prestressed Concrete Containment Vessel (PCCVs), and LNG tanks under extreme loading are significantly lacking. Especially, researches on possible secondary fire scenarios after terror, bombing, collision of vehicles and vessels on concrete structures have not been performed domestically where most of the past researches related to extreme loadings on structures focused on an independent isolated extreme loading scenario. Due to the outcry of public concerns and anxiety of potential terrorist attacks on major infrastructures and structures, a study is urgently needed at this time. Therefore, in this study, the bi-directional prestressed concrete $1400{\times}1000{\times}300mm$ panels applied with 430 kN prestressing force using unbonded prestressing thread bars were experimentally evaluated under impact, fire, and impact-fire combined loadings. Due to test site restrictions, impact tests were performed with 14 kN impactor with drop heights of 10m and 3.5 m to evaluate impact resistance capacity. Also, fire and impact-fire combined loading were tested using RABT fire loading curve. The measured residual strength capacities of PSC and RC specimens applied with impact, fire, impact-fire combined loadings were compared with the residual strength capacity of undamaged PSC and RC specimens for evaluation. The study results can be used as basic research data for related research areas such as protective design and numerical simulation under extreme loading scenarios.

Studies on Chemical Resistance of Mites. II. Orchard Mite Control and their Resistance to Metasystox, Folidol and C-8514 in Korea (응애류의 약제 저항성에 관한 연구 II . Metasystox, Folidol 및 C-8514에 대한 과수응애류의 저항성과 방제시험)

  • Lee S. C.;Yoo J. K.
    • Korean journal of applied entomology
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    • v.10 no.2
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    • pp.109-116
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    • 1971
  • The study involved determination of resistance levels of spider mites to Metasystox, Folidol and C-8514 using slide dip technique: a feid trial of alternative acaricides using an O/P resistant strain. 1. Resistant strains of two-spotted spider mite( Tetranychus urticae Koch) were collected from Taegu, Kyungsan, Chunchun, Yesan, Suwon, Osan and Chungju, and kept in the glasshouse through the experiments. Resistant strains of European red mite (Panonychus ulmi Koch) were collected from Chungju, Taegu, Yesan, Chunchun, Suwon and Whasung, and Wonju susceptible was collected. Immediately after collection, tests were applied. All strains except susceptible populations had regularly been sprayed with Organo-phosphates including Parathion (or Folidol), Metasystox, Phenkapton and Trithion for more than the ten Bast years; and Organo-chlorines such as Kelthane and C-8514 more than five years. Comparisons of the resistant strains and susceptible strains at the $LC_50$ values are as follows: a. With Metasystox, resistance levels of the Chungju, Taegu, Yesan, Chunchun and Suwon resistant strains of P. ulmi were respectively, 96,52,4,3 and 2, times as resistant as the Wonju susceptible strain. b. With Folidol, resistance levels of the Chungju, Chunchun, Yesan, Whasung and Suwon strains of P. ulmi showed respectively, 126, 48, 33, 30 and 6-fold resistance levels over the susceptible strain. c. With C-8514, resistance levels of the Taegu, Suwon, Whasung and Chungju strains of P. ulmi were 42, 31, 30 and 20 times greater than the susceptible strain, respectively. d. With Metasystox, resistance levels of the Taegu, Chunchun, Yesan and Suwon, strains of T urticae were respectively, 32,29,25 and 17 times as resistant as the susceptible strain. e. With C-8514, resistance levels of the Taegu, Chungju and Kyungsan strains of T. urticae showed respectively, 59, 29 and 19-fold resistance levels over the Osan strain. 2. Field trials were carried out to assess the toxicities of eleven alternative materials which would be used for control of O/P resistant strain of Panonychus ulmi. The acaricide groups represented were 2 Organo-chlorines (Kelthane MF and Prethylen), 1 carbamate (Furadan), 1 nitrophenyl (Morocide), 1 carbonate (Morestan), 1 tin(Plictran), 1 fluorine (Nissol), 2 mixtures (Fundal and Banmite) and Organo-phosphate (Phenkapton). Of all acaricides tested Kelthane, Plictran, Fundal and Morestan were the most effective; fol]owed by Banmite, Furadan, Prethylen and Nissol. Sumite and Morocide were intermediate, but Phenkapton(Organo-phosphate) was very poor. In other words, a first application of the above outstanding materials gave very high degrees of control of O/P resistant population of European red mite for about 7 to 12 days. However, the results indicate that secondary application would sometimes be necessary. There was no foliage damage to apple trees by any of the acaricides tested of the concentrations used.

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Field Application Techniques of Simultaneous Mating Disruptor Against Grapholita molesta and G. dimorpha (복숭아순나방과 복숭아순나방붙이에 대한 동시 교미교란제의 현장 적용 기술)

  • Cho, Jum-Rae;Park, Chang-Gyu;Park, Il-Kweon;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.57 no.3
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    • pp.209-220
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    • 2018
  • Mating disruption (MD) has been widely used to effectively control Grapholita molesta in apple orchards. A simultaneous mating disruption (SMD) techniques have been developed to control both G. molesta and G. dimorpha. This study was performed to determine the practical parameters to apply the SMD technique to field conditions. To determine the application amount of SMD lures, a dispenser containing 10 mg pheromone was placed at different numbers of trees in an orchard. Application at every other tree (= one dispenser per two trees) was relatively safe to expect effective MD efficiency in both wax and polyethylene (PE) formulations. One time application at the end of March was enough to maintain a year round MD efficacy against both species. A fence treatment using food trap was applied to prevent any immigratory mated females from nearby untreated regions. To enhance the food trap by adding host-derived secondary compounds, terpinyl acetate (TA) was screened to be effective to attract females of Grapholita molesta among six compounds contained in apple fruit extracts. Among different TA concentrations, 0.05% TA treatment was the most effective to attract the adults. A mixture of TA and sugar was effective to attract and kill females and called FAKT (female attract-to-kill techniques). FAKT was treated at approximately 6 m interval at the edge of the apple orchards. The females trapped by the FAKT included mated females possessing vitellogenic oocytes. SMD supplemented with FAKT maintained the high MD efficacy and significantly suppressed leaf damage induced by the two insect pests compared to control or single SMD treatment.

Effect of High Protein Diet and Resveratrol Supplementation on the Nutritional Status and Immunoreactivity in the Irradiation-induced Inflammatory Rats (방사선 조사된 흰쥐에서 고단백식이와 레스베라트롤 첨가가 영양상태 및 면역기능 증진에 미치는 효과)

  • Kim, Kyoung-Ok;Chun, Mi-Son;Kang, Seung-Hee;Kim, Hyun-Sook
    • Journal of Nutrition and Health
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    • v.42 no.7
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    • pp.605-614
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    • 2009
  • Most cancer patients are treated with surgery, chemotherapy or radiation as anticancer therapies. Especially in the case of radiation, these treatments produce adverse effects such as vomiting, weight loss, anorexia, normal cell damage and malabsorption. The major goal of this study was to determine the effect of irradiation on the nutritional and immune status in irradiated rats. A secondary goal was to determine the effectiveness of high protein diet (HP) and resveratrol (Res) in minimizing the adverse effects of radiation. Rats were divided into four groups: normal diet (NP), HP, NP + Res and HP + Res groups. Each group was further divided into subgroups that received radiation (RT group) and one that did not (non-RT group). Each diet was supplied from $12^{th}$ day prior to irradiation treatment with irradiation dose of 17.5 Gy. The diets were continued until 10th day after radiation treatment and animals were sacrificed. The radiation treatment showed decreased body weight, serum protein and HDL levels and increased TG and LDL levels in nutritional status. HP, NP + Res and HP + Res groups reduced the level of serum LDL and TG in irradiated rats. NP + Res and HP + Res groups increased reduced albumin level of serum in RT group. In case of immune status, the radiation treat-ment showed decreased WBC, lymphocytes and increased neutrophil and eosinophil levels. The levels of serum IL-2 and IL-6 were significantly increased by radiation, however the cytokine levels decreased in all dietary treatment groups. These results showed that high protein diet and resveratrol supplementation seem to minimize the adverse effects of radiation on lipid nutritional status and inflammation response in the rat model.

Material Characteristics and Deterioration Assessment of the Stone Buddhas and Shrine in Unjusa Temple, Hwasun, Korea (화순 운주사 석조불감의 재질특성과 풍화훼손도 평가)

  • Park, Sung-Mi;Lee, Myeong-Seong;Choi, Seok-Won;Lee, Chan-Hee
    • Journal of Conservation Science
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    • v.24
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    • pp.23-36
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    • 2008
  • The stone Buddhas and Shrine of Unjusa temple (Korea Treasure No. 797) in Hwasun formed in Koryo Dynasty are unique style which the Buddha faces each other the back parts of south and north within the stone Shrine. The stone Buddhas and Shrine are highly evaluated in historical, artistic and academic respects. But, the stone properties have been exposed in the open system various aspects of degradations weathered for a long time without specific protective facilities. The rock materials of the stone Buddhas and Shrine are about 47 blocks, and total press load is about 56.6 metric ton. The host rocks composed mainly of white grey hyaline lithic tuff and rhyolitic tuff breccia. In addition, biotite granite used as part during the restoration works. The chemical index of alteration for host tuffaceous rocks and the replacement granites range from 52.1 to 59.4 and 50.0 to 51.0, respectively. Weathering types for the stone Buddhas and Shrine were largely divided with physical, chemical and biological weathering to make a synthetic deterioration map according to aspects of damage, and estimate share as compared with surface area. Whole deterioration degrees are represented that physical weathering appeared exfoliation. Chemical weathering is black coloration and biological weathering of grey lichen, which show each lighly deterioration degrees. According to deterioration degree by direction of stone Buddhas and Shrine, physical weathering mostly appeared by 39.1% on the sorthern part, and chemical weathering is 61.2% high share on the western part. Biological weathering showed 38.3% the largest distribution on the southern part. Therefore, it is necessary to try hardening for the parts with serious cracks or exfoliations, remove secondary contaminants and organisms through regular cleaning. Also necessary to make a plan to remove moisture of the ground which causes weathering, and estimate that need established and scientific processing through clinical demonstration of conservation plan that chooses suitable treatment.

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Frameless Fractionated Stereotactic Radiaton Therapy in Recurrent Head & Neck Cancers (국소재발된 두경부종양의 무고정틀 정위적 분할방사선치료)

  • Kim In-Ah;Choi Ihl-Bhong;Jang Ji-Young;Kang Ki-Mun;Jho Seung-Ho;Kim Hyung-Tae;Lee Kyung-Jin;Choi Chang-Rak
    • Korean Journal of Head & Neck Oncology
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    • v.14 no.2
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    • pp.156-163
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    • 1998
  • Background & Objectives: Frameless fractionated stereotactic radiotherapy(FFSRT) is a modification of stereotactic radiosurgery(SRS) with radiobiologic advantage of fractionation without losing mechanical accuracy of SRS. Local recurrence of head and neck cancer at or near skull base benefit from reirradiation. Main barrier to successful palliation is dose limitation secondary to normal tissue tolerance. We try to evaluate the efficacy and safety of FFSRT as a new modality of reirradaton in these challenging patients. Materials & Methods: Seven patients with recurrent head & neck cancer involving at or near skull base received FFSRT from September 1995 to November 1997. Six patients with nasopharyngeal cancer had received induction chemotherapy and curative radiation therapy. One patient with maxillary sinus cancer had received total maxillectomy and postoperative radiation therapy as a initial treatment. Follow-up ranged from 11 to 32 months with median of 24 months. Three of 7 patients received hyperfractionated radiation therapy(1.1-1.2Gy/fraction, bid, total 19.8-24Gy) just before FFSRT. All patients received FFSRT(3-5Gy/fraction, total 15-30Gy/5-10fractions). Chemotherapy(cis-platin $100mg/m^2$) were given concurrently with FFSRT in four patients. Second course of FFSRT were given in 4 patients with progression or recurrence after initial FFSRT. Because IF(irregularity factor; ratio of surface area of target to the surface area of sphere with same volume as a target) is too big to use conventional stereotactic RT using multiple arc method for protection of radiation damage to critical normal tissue, all patients received FFSRT with conformal method using irregular static ports. Results: Five of 7 patients showed complete remission in follow-up CT &/or MRI. Three of these five patients who developed marginal, in-field, and out-field recurrences, respectively. Another one of complete responders has been dead of G-I bleeding without evidence of local recurrence. One partial responder who showed progressive disease 15 months after initial FFSRT has received additional FFSRT, and then he is well-being with symptomatic improvement. One minmal responder who showed progression of locoregional disease 9 months after $1^{st}$ FFSRT has received 2nd FFSRT, and then he is alive with stable disease. Five of 7 case had showed direct invasion to skull base and had complaint headache and various symptoms of cranial nerve involvement. Four of these five case showed improvement of neurologic symptoms after FFSRT. No significant neurologic complicaltion related to FFSRT was observed during follow-up periods. Tumor volumes were ranged from 3.9 to 50.7 cc and surface area ranged from 16.1 to $114.9cm^2$. IF ranged from 1.21 to 1.74. The average ratio of volume of prescription isodose shell to target volume was 1.02 that indicated the improvement of target coverage and dose distribution with FFSRT with conformal method compared to target coverage with FFSRT with multiple arc method. Conclusion: Our initial experience suggests that FFSRT with conformal method was relatively effective and safe modality in the treatment of recurrent head and neck cancer involving at or near skull base. Treatment benefit included good palliation of symptoms and reasonable radiographic response. However, more experience and additional follow-up are needed to better assess its ultimate role in treating these challenging patients.

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A Study on Improvement of the police disaster crisis management system (경찰의 재난위기관리 개선에 관한 연구)

  • Chun, Yongtae;Kim, Moonkwi
    • Journal of the Society of Disaster Information
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    • v.11 no.4
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    • pp.556-569
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    • 2015
  • With about 75% of the population of Korea criticizing the government's disaster policy and a failure to respond to large-scale emergency like the Sewol ferry sinking means that there is a deep distrust in the government. In order to prevent dreadful disasters such as the Sewol ferry sinking, it is important to secure a prime time with respect to disaster safety. Improving crisis management skills and managerial role of police officers who are in close proximity to the people is necessary for the success of disaster management. With disaster management as one of the most essential missions of the police, as a part of a national crisis management, a step by step strengthening of the disaster safety management system of the police is necessary, as below. First, at the prevention phase, law enforcement officers were not injected into for profit large-scale assemblies or events, but in the future the involvement, injection should be based on the level of potential risk, rather than profitability. In the past and now, the priortiy was the priority was on traffic flow, traffic communication, however, the paradigm of traffic policy should be changed to a safety-centered policy. To prevent large-scale accidents, police investigators should root out improper routines and illegal construction subcontracting. The police (intelligence) should strengthen efforts to collect intelligence under the subject of "safety". Second, with respect to the preparatory phase, on a survey of police officers, the result showed that 72% of police officers responded that safety management was not related to the job descriptions of the police. This, along with other results, shows that the awareness of disaster safety must be adopted by, or rather changed in the police urgently. The training in disaster safety education should be strengthened. A network of experts (private, administrative, and police) in safety management should be established to take advantage of private resources with regard to crisis situtions. Third, with respect to the response phase, for rapid first responses to occur, a unified communication network should be established, and a real-time video information network should be adopted by the police and installed in the police situation room. Fourth, during the recovery phase, recovery teams should be injected, added and operated to minimize secondary damage.

A Study on the Traditional Geographic System Recognition and Environmental Value Estimate of Hannamkeumbuk-Keumbuk Mountains for the Establishment of a Management Plan (관리계획 수립을 위한 한남금북.금북정맥의 전통적 지리체계인식과 환경가치 추정 연구)

  • Kang, Kee-Rae;Kim, Dong-Pil
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.1
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    • pp.23-33
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    • 2012
  • In this study, how much users of Hannamkeumbuk Keumbuk Mountains are aware of Baekdaegan and its attached mountain chains, a traditional geographic system, according to Sangyungpyo and basic data like the degree of awareness and use-behaviors, etc. have been studied. In addition, the environmental value of Hannamkeumbuk Keumbuk Mountains separating the central and the southern part of Korea among attached mountain ranges, secondary mountain chains, which act as an ecosystem buffer in the Baekdudaegan Range, has been estimated at the current amount of currency. In the questions of the perception of the traditional classification standard of mountain chains and Baekdudaegan, more than 70% of respondents answered that they had heard of or known them but 66.8% werenot aware of Hannamkeumbuk Keumbuk Mountains. While the awareness for Baekdudaegan is high, the perception of its attached mountain chains was very poor. DBDC responder system and CVM, which is used widely for the value estimate method of environment goods, were used. As the result, an additional benefit got when a person visits Hannamkeumbuk Keumbuk mountains was estimated as 5,813 won. It could find out that this amount was very low compared with 51,984 won, average visit cost. It judged that the reason was that damage of environmental conditions, the monotony of the trails and progress of indiscriminate environmental destruction, etc. The results of this study will offer a new perspective on public relations activities and resource conservation of Baekdudaegan and its attached mountain chains and estimate perceptions and efficient services for visitors to HannamKeumbuk Keumbuk Mountains. This study will act as data for basic planning and management to increase the mountains' value and to preserve them. Further studies are needed to make a frame of work division and management with various organizations so that the management of Hannamkeumbuk-Keumbuk Mountains may be properly established and their value may been hanced.

Womans experience of Risk Situation on the High-Risk Pregnancy (여성의 고위험 임신에 대한 경험)

  • Kim, Kyung-Won;Lee, Kyung-Hye
    • Women's Health Nursing
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    • v.4 no.1
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    • pp.161-178
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    • 1998
  • In spite of the great progress of the theory and skill of the Nursing Care & Medical area in relation to pregnancy, nurses in clinics face up to many challenges in maternity nursing care areas. The reason is that the mobility and mortality of mothers was sharply decreased and the unknown high-risk diseases of pregnancy woman in the past is made public. That's why it is difficult to meet the pregnancy woman in natural process from pregnancy to delivery in recently. Admission rooms are filled with high-risk pregnancy women. As a matter of fact, we have done nursing care into the surface symptoms and diseases of high-risk pregnancy women so far. We have been indifferent to a long period hospitalization, separation from family, and conflict of repeated examination. Therefore, it is widely spread to understand the emotional conflict experienced by high-risk pregnancy women and to need for nursing intervention to bring up about emotional support and the ability of perception in psychological crisis. Although the pregnancy woman judged in high-risk should carry out normal task of pregnancy, she have to be confronted with secondary risk situation. The health of self & fetus threatened by the risk situation could be decreased through care plan, but psychological stress increases. Therefore, the pregnancy brings into non-control state. It is important to ask that what the hospitalized pregnancy women in high-risk think of themselves status. Because misunderstanding or serious anxiety of themselves status put into mother and fetus in danger. And adaptation mode makes all the difference. I would like to consider how nurses could deal with this high-risk circumstances in the position of pregnancy woman on the basis of the above fact. This study uses phenomenological method to suggest the basis material for nurses to do nursing intervention in view of pregnancy woman. Because this method understands the nature of true life of pregnancy woman throughly. The phenomenological method is the sources to describe or explain affluently the process generated in confirmation areas and environment and is the application for readers to understand and recognize clinic reality and then apply this method to reasoning study place or other places. Specifically, the phenomenon study method, one of the phenomenological method, is applied. The use of that method is to describe and generalize the experience in environment exactly. The study of this study is as follows : Among 187 descriptive stamens from 8 study participants are classified into 42 theme cluster at the stage of the first analysis. Those theme is categorized into 8 sub-subjects such as anxiety of uncertainty, foreknowledge about risk circumstance, will power about overcome, unsettled feeling about hospital, relief, optimistic thought, family support, and indifferences. At the last stage of analysis, those things are categorized into 3 subjects. When high-risk pregnancy woman foretell the situation, they feel unsettlement about uncertainty and untrust feeling about hospital. But they are ease with family support and hospital support. On the other hand, they express indifferent 3-way structure response to the situation having will of overcome and exceeding optimistic thought. In those statements, the experience by pregnancy woman shows 3 respect subjects. 1. They are anxious of this situation and are in desperation and don't recognize their role to be carried out 2. They think of this situation as normal process of pregnancy and are not concerned that this can give themselves and fetus fatal damage. 3. The pregnancy women will never confront this situation. This study shows the pregnancy woman has anxiety and optimistic relief about the situation, and ignores and optimistic relief about the situation, and ignores many things. Therefore, nurses in clinic should give pregnancy woman knowledge and information about the high-risk and help them to deal with the situation spontaneously. High-risk pregnancy woman should have the care plan in respect of the right perception. And the nurse know that their support help out pregnancy woman overcome the crisis in this respect of the special nursing intervention.

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Melanogenesis regulatory constituents from Premna serratifolia wood collected in Myanmar

  • WOO, SO-YEUN
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.21-22
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    • 2019
  • Melanin is a mixture of pigmented biopolymers synthesized by epidermal melanocytes that determine the skin, eye, and hair colors. Melanocytes produce two different kinds of melanin, eumelanin (dark brown/black insoluble pigments found in dark skin and dark hair and pheomelanin (lighter red/yellow). The biological role of melanin is to prevent skin damage by ultraviolet (UV) radiation. However, the overproduction or deficiency of melanin synthesis could lead to serious dermatological problems, which include melasma, melanoderma, lentigo, and vitiligo. Therefore, regulating melanin production is important to prevent the pigmentation disorders. Myanmar has a rich in natural resources. However, the chemical constituents of these natural resources in Myanmar have not been fully investigated. In the effort to search for compounds with anti-melanin deposition activity from Myanmar natural resources, five plants were collected in Myanmar. Extracts of these collected five plants were tested for anti-melanin deposition activity against a mouse melanoma cell line (B16-F10) induced with ${\alpha}$-melanocyte-stimulating hormone (${\alpha}$-MSH) and 3-isobutyl-1-methylxanthine (IBMX), and their anti-melanin deposition activities were compared with the positive control, arbutin. Among the tested extracts, the CHCl3 extracts of the Premna serratifolia (syn: P. integrifolia) wood showed anti-melanin deposition activities with IC50 values of $81.3{\mu}g/mL$. Hence, this study aims to identify secondary metabolites with anti-melanin deposition activity from P. serratifolia wood of Myanmar. P. serratifolia belongs to the Verbenaceae family and is widely distributed in near western sea coast from South Asia to South East Asia, which include India, Malaysia, Vietnam, Cambodia, and Sri Lanka. People in Tanintharyi region located in the southern part of Myanmar utilize the P. serratifolia, Sperethusa crenulata, Naringi crenulata, and Limonia acidissima as Thanaka, traditional cosmetics in Myanmar. Thanaka is applied in the form of paste onto skins to make it smooth and clear, as well as to prevent wrinkles, skin aging, excessive facial oil, pimples, blackheads, and whiteheads. However, the chemical constituents responsible for their cosmetic properties are yet to be identified. Moreover, the chemical constituents of P. serratifolia was almost uncharacterized. Investigation of the P. serratifolia chemical constituents is thus an attractive endeavor to discover new anti-melanin deposition active compounds. The investigation of the chemical constituents of the active CHCl3 extract of P. serratifolia led to isolation of four new lignoids, premnan A (1), premnan B (2), taungtangyiol C (3), and 7,9-dihydroxydolichanthin B (4), together with premnan C (5) (assumed to be an artifact), one natural newlignoid,(3R,4S)-4-(1,3-benzodioxol-5-ylcarbonyl)-3-[(R)-1-(1,3-benzo dioxol-5-yl)-1-hydroxy methyl]tetrahydro-2-furanone (6), and five known compounds (7-11)1,2). The structures of all isolated compounds were determined on the basis of their spectroscopic data and by comparison with the reported literatures. The absolute configurations of 1-3 and 5 were also determined by optical rotation and circular dichroism (CD) data analyses1). The anti-melanin deposition activities of all the isolated compounds were evaluated against B16-F10 cell line. 7,9-Dihydroxydolichanthin B (4) and ($2{\alpha},3{\alpha}$)-olean-12-en-28-oic acid (11) showed strong anti-melanin deposition activities with IC50 values of 18.4 and $11.2{\mu}M$, respectively, without cytotoxicity2). On the other hand, compounds 1-3, 5, and 7 showed melanogenesis enhancing activities1). To better understand their anti-melanin deposition mechanism, the effects of 4 and 11 on tyrosinase activities were investigated. The assay indicated that compounds 4 and 11 did not inhibit tyrosinase. Furthermore, we also examined the mRNA expression of microphthalmia-associated transcription factor (MITF), tyrosinase (TYR), tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2). Compounds 4 and 11 down-regulated the expression of Tyr and Mitf mRNAs, respectively. Although the P. serratifolia wood has been used as traditional cosmetics in Myanmar for centuries, there are no scientific evidences to support its effectiveness as cosmetics. Investigation of the anti-melanin deposition activity of the chemical constituents of P. serratifolia thus provided insight into the effectiveness of the P. serratifolia wood as a cosmetic agent.

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