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Distribution Characteristics and Management Plan of the Wisteria Habitat (No. 176 natural monument) of Beomeosa Temple in Busan (부산 범어사 등나무군락지의 등나무 분포 특성 및 관리방안)

  • Lee, Chang-Woo;Oh, Hae-Seong;Lee, Cheol-Ho;Choi, Byoung-Ki
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.2
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    • pp.77-86
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    • 2017
  • A study on the population ecology of gregarious Wisteria habitat was conducted in Beomeosa temple, Busan. The area has been protected since it was designated as No. 176 natural monument in 1966. Such a large habitat of native wisteria (Wisteria floribunda DC.) in Korea is very rare so that it has a very high academic value. However, there are no high-resolution researches on the distribution and ecology of wisteria in the Gregarious Wisteria Habitat of Beomeosa Temple. The study aimed to identify the distribution and characteristics of wisteria populations in the Wisteria habitat. The study identified the distribution of Wisteria, RCC, the climbing direction, the plant and flora in the research area in the Gregarious Wisteria Habitat of Beomeosa Temple in Busan and the surrounding areas based on an on-site research. As a result, the total number of the wisteria populations in the research area was confirmed to be 1,158 and the RCC of wisteria was on average 69.0 mm (${\pm}45.5$) and in maximum 365 mm. In terms of the climbing direction, the number of wisteria that climbs clockwise or counterclockwise was determined to be 40. It was identified that there are 28 taxa of the climbing plant species and the wisteria of the same kind was the most favorable. The populations were found to be dispersed adjacent to the valleys, and were found to be maintained by constant disturbance. 76.6 % of the population was found to be distributed in the valley forest, and the Carpinus tschonoskii-Pseudosasa japonica forest, Pueraria lobata community and Pinus densiflora forest were found to be relatively dispersed. The study proposed to conduct the follow-up researches to preserve the wisteria that is spreading in this research area, the wisteria with the highest RCC and regional habitat through continuous monitoring; and maintain the protection area of No. 176 natural monument; and discussed the management measures and approaches that reflect the habitat.

Recent Advancement in the Stem Cell Biology (Stem Cell Biology, 최근의 진보)

  • Harn, Chang-Yawl
    • Journal of Plant Biotechnology
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    • v.33 no.3
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    • pp.195-207
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    • 2006
  • Stem cells are the primordial, initial cells which usually divide asymmetrically giving rise to on the one hand self-renewals and on the other hand progenitor cells with potential for differentiation. Zygote (fertilized egg), with totipotency, deserves the top-ranking stem cell - he totipotent stem cell (TSC). Both the ICM (inner cell mass) taken from the 6 days-old human blastocyst and ESC (embryonic stem cell) derived from the in vitro cultured ICM have slightly less potency for differentiation than the zygote, and are termed pluripotent stem cells. Stem cells in the tissues and organs of fetus, infant, and adult have highly reduced potency and committed to produce only progenitor cells for particular tissues. These tissue-specific stem cells are called multipotent stem cells. These tissue-specific/committed multipotent stem cells, when placed in altered environment other than their original niche, can yield cells characteristic of the altered environment. These findings are certainly of potential interest from the clinical, therapeutic perspective. The controversial terminology 'somatic stem cell plasticity' coined by the stem cell community seems to have been proved true. Followings are some of the recent knowledges related to the stem cell. Just as the tissues of our body have their own multipotent stem cells, cancerous tumor has undifferentiated cells known as cancer stem cell (CSC). Each time CSC cleaves, it makes two daughter cells with different fate. One is endowed with immortality, the remarkable ability to divide indefinitely, while the other progeny cell divides occasionally but lives forever. In the cancer tumor, CSC is minority being as few as 3-5% of the tumor mass but it is the culprit behind the tumor-malignancy, metastasis, and recurrence of cancer. CSC is like a master print. As long as the original exists, copies can be made and the disease can persist. If the CSC is destroyed, cancer tumor can't grow. In the decades-long cancer therapy, efforts were focused on the reducing of the bulk of cancerous growth. How cancer therapy is changing to destroy the origin of tumor, the CSC. The next generation of treatments should be to recognize and target the root cause of cancerous growth, the CSC, rather than the reducing of the bulk of tumor, Now the strategy is to find a way to identify and isolate the stem cells. The surfaces of normal as well as the cancer stem cells are studded with proteins. In leukaemia stem cell, for example, protein CD 34 is identified. In the new treatment of cancer disease it is needed to look for protein unique to the CSC. Blocking the stem cell's source of nutrients might be another effective strategy. The mystery of sternness of stem cells has begun to be deciphered. ESC can replicate indefinitely and yet retains the potential to turn into any kind of differentiated cells. Polycomb group protein such as Suz 12 repress most of the regulatory genes which, activated, are turned to be developmental genes. These protein molecules keep the ESC in an undifferentiated state. Many of the regulator genes silenced by polycomb proteins are also occupied by such ESC transcription factors as Oct 4, Sox 2, and Nanog. Both polycomb and transcription factor proteins seem to cooperate to keep the ESC in an undifferentiated state, pluripotent, and self-renewable. A normal prion protein (PrP) is found throughout the body from blood to the brain. Prion diseases such as mad cow disease (bovine spongiform encephalopathy) are caused when a normal prion protein misfolds to give rise to PrP$^{SC}$ and assault brain tissue. Why has human body kept such a deadly and enigmatic protein? Although our body has preserved the prion protein, prion diseases are of rare occurrence. Deadly prion diseases have been intensively studied, but normal prion problems are not. Very few facts on the benefit of prion proteins have been known so far. It was found that PrP was hugely expressed on the stem cell surface of bone marrow and on the cells of neural progenitor, PrP seems to have some function in cell maturation and facilitate the division of stem cells and their self-renewal. PrP also might help guide the decision of neural progenitor cell to become a neuron.

Content and Characteristics of Forest Cover Changes in North Korea (북한(北韓) 지역(地域) 산림면적(山林面積) 변화(變化)의 규모(規模)와 특성(特性))

  • Lee, Kyu-Sung;Joung, Mi-Reyoung;Yoon, Jung-Sook
    • Journal of Korean Society of Forest Science
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    • v.88 no.3
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    • pp.352-363
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    • 1999
  • It has been rare to obtain reliable information related to the size of forest land in North Korea. Several sources of forest statistics, ranging from the first map of forest distribution in Korean Peninsula produced in 1910 to official data reported by the North Korea Government in 1997, were gathered and analyzed to define the characteristics of forest cover changes over years. In addition, Landsat satellite data obtained from 1973 to 1993 were processed for the two study areas of the provinces of Pyungyang and Heasan, where the topography and land use pattern are significantly different each other. Using three sets of multitemporal Landsat imagery, land cover ma-ps were produced by computer classification. Although forest statistics reported before 1990 are somewhat inconsistent, they mere gradually decreasing over years. The estimates of 1991 satellite data and the recent statistics reported in 1998 shows very steep decline in forest lands as compared to the ones before 1990. The abrupt decrease of forest lands after 1990 was also found on the detailed analysis of Landsat data for the two study areas of Pyungyang and Heasan. The rapid decline of forest lands may have something to do with the poor economic situation of the country and the continuing natural disasters of severe flooding and drought. Unstocked forest, which was not classified into forest land, was a very distinct and pervasive land cover type that can be easily observed on satellite imagery. Since unstocked forest land in North Korea may be a critical factor for degrading environmental quality as well as for the continuing natural disasters, further analysis is necessary to define the exact extent and the physical characteristics of the cover type.

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Vegetation Structure and Site Environment of Natural Habitat of an Endangered Plant, Viola websteri (멸종위기 식물 왕제비꽃 자생지의 식생구조 및 입지환경)

  • Song, Jae-Mo;Lee, Gi-Yeoung;Kim, Nam-Young;Yi, Jae-Seon
    • Journal of Korean Society of Forest Science
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    • v.99 no.3
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    • pp.267-276
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    • 2010
  • This study was performed to obtain basic data about vegetation structure and site environment of rare and endangered plant, viola websteri in five natural habitats. The dominant species of Hongcheon habitat were Pyrus pyrifolia (tree layer), Morus bombycis (subtree layer), Pyrus pyrifolia (shrub layer) and Isodon inflexus (herb layer). Mt. Yeonin habitat were dominated by Quercus mongolica (tree layer), Morus bombycis (subtree layer), Philadelphus schrenckii (shrub layer) and Viola websteri (herb layer). Mt. Yumyung habitat were dominated by Cornus controversa (tree layer), Morus bombycis (subtree layer), Fraxinus rhynchophylla (shrub layer) and Adenocaulon himalaicum (herb layer). Mt. Daebu habitat were dominated by Acer mono (tree layer), Staphylea bumalda (subtree layer), Staphylea bumalda(shrub layer) and Dryopteris crassirhizoma (herb layer). And the dominant species of Mt. Worak habitat were Larix leptolepis (tree layer), Fraxinus rhynchophylla (subtree layer), Alangium platanifolium var. macrophylum (shrub layer) and Adenocaulon himalaicum (herb layer). It was found out that the average acidity of soil pH was 5.23; 0.30ds/m for electron conductivity; 12.6% for organic matter content; 0.68% for total nitrogen; 21.66 ppm for available phosphorous; and 23.45 cmol(+)/kg for CEC. Interchangeable cation was decreased in order of $Ca^{2+}$ > $Mg^{2+}$ > $K^{2+}$. Viola websteri had positive association with Polygonatum odoratum var. pluriflorum and Geranium thunbergii but negative association with Poa sphondylodes. Species diversity index(H'), maximum Species diversity index (H' max), evenness(J') and dominance (1-J'), of investigated sites ranged 0.6816 (Mt. Worak)~0.9656 (Mt. Daebu), 1.0000 (Mt. Yeonin)~1.3010 (Hongcheon, Gangwon), 0.5330 (Mt. Worak)~0.8947 (Mt. Daebu) and 0.1053 (Mt. Daebu)~0.4670 (Mt. Worak) in woody layer and 1.0414 (Mt. Yumyung)~1.3295 (Mt. Worak), 1.4314 (Mt. Yumyung)~1.6435 (Mt. Daebu), 0.6984 (Hongcheon, Gangwon)~0.8356 (Mt. Worak) and 0.1644 (Mt. Worak)~0.3016 (Hongcheon, Gangwon) in herb layer, respectively.

Soft Tissue Malignant Myoepithelioma in the Extremities (사지에 발생한 연부 조직 악성 근상피종)

  • Kong, Chang-Bae;Lee, Jung-Wook;Koh, Jae-Soo;Song, Won Seok;Cho, Wan Hyeong;Jeon, Dae-Geun;Lee, Soo-Yong
    • The Journal of the Korean bone and joint tumor society
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    • v.20 no.2
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    • pp.54-59
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    • 2014
  • Purpose: We report the diagnosis, treatment outcomes and prognosis of the patients with soft tissue malignant myoepithelioma in the extremities. Materials and Methods: We retrospectively reviewed 6 patients with soft tissue malignant myoepithelioma in the extremities who were treated at our institution between 2008 and 2014. Two patients received unplanned excision at another hospital and remaining 4 patients underwent the biopsy procedures and received wide excision at our hospital. Results: There were 3 men and 3 women with mean age of 41 (33-54) years. The average follow up was 28 (9-45) months. Among the 6 patients, only 4 patients underwent biopsy procedures under the impression of malignant soft tissue sarcoma. Surgical margins for these 4 patients were negative. Two patients who had unplanned excision received another re-excision and one of them showed no residual tumor in the resected specimen. Local recurrences were developed in all patients and distant metastasis in 4 patients. All 4 patients who developed distant metastasis died due to disease progression. Among the 2 patients who developed local recurrence only, one patient has another local recurrence after re-operation and remaining one patient is no evidence of disease for 2 years after resection of locally recurred mass. Conclusion: Soft tissue malignant myoepithelioma in the extremities is a rare disease and shows an aggressive behavior. Appropriate biopsy under the impression of soft tissue malignancy is necessary and complete surgical resection with wide margins is the recommended treatment of choice.

Treatment and Prognosis of Chondroblastoma (연골모세포종의 치료 결과)

  • Lee, Young-Kyun;Han, Il-kyu;Oh, Joo-Han;Lee, Sang-Hoon;Kim, Han-Soo
    • The Journal of the Korean bone and joint tumor society
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    • v.13 no.2
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    • pp.81-87
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    • 2007
  • Purpose: Chondroblastoma of bone is rare with the potential for local recurrence and metastasis. A retrospective review of 30 patients with chondroblastoma of bone treated at a single institution during a 24-year period was conducted to determine the clinical outcome and relevant prognostic factors. Materials and Methods: Thirty patients with biopsy-proven chondroblastoma of bone, treated between September of 1981 and September of 2005, were retrospectively reviewed. There were 16 men and 14 women with an average follow-up period of 7.2 years (range, 1.6~21.2). The most common sites were the distal femur (n=7), proximal humerus (n=6), proximal tibia (n=6) and proximal femur (n=4). The average age of the patients was 20 years (range, 12~47) with closed physes in 20 patients(67%.) Twenty-seven patients(90%) were treated by curettage of the tumor with or without bone grafting or cementing. Three patients(10%) were treated with en bloc resection. Clinical and pathological factors reported to be associated with poor outcome were analyzed. Results: Four local recurrences(13%) developed in postoperative 4, 6, 7 and 16 months. These patients underwent further curettage (once in 2 patients and twice 2) and had no further recurrence. All patients showed no evidence of disease at the final follow-up. Local recurrence developed in the two cases which removal of the tumor was incomplete. Curettage and bone-grafting (1) and cementing (1) were performed in the two other cases with local recurrences. In contrast, no local recurrences were observed in the 3 cases treated with en-bloc resection. The status of physes or the histologic presence of aneurysmal bone cyst, the anatomic location of the tumor did not affect local recurrence. Conclusion: Adequate removal of the tumor with aggressive curettage or en bloc resection seems to be necessary to prevent local recurrence in chondroblastoma. The status of physes, the histologic presence of aneurysmal bone cyst or the anatomic location of the tumor was not related with local recurrence.

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The Immunohistochemical Expression of Collagens and the Morphogenesis in the Developing Mandible of Human Embryos and Fetuses (배자와 태아에서 하악골의 형태발생 및 교원질 발현에 관한 면역조직화학적 연구)

  • Kook, Yoon-Ah;Kim, Sang-Cheol;Kim, Eun-Cheol;Kim, Oh-Hwan;Kim, Jong-Ghee
    • The korean journal of orthodontics
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    • v.26 no.2 s.55
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    • pp.187-196
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    • 1996
  • Underlying malocclusions and dentofacial deformities are often related to variations in the craniofacial development. Type I and type II collagens are considered the major collagens of bone and cartilage respectively. Monitoring the patterns of those protein expressions during development will Provide a basis for the understanding of normal and abnormal growths. This study was undertaken to investigate the morphogenetic changes and the expression patterns of type I and II collagen proteins involved in the developing mandible of human embryos and fetuses. 50 embryos and fetuses were studied with Hematoxylin and Eosin, Alcian, blue-PAS, Masson Trichrome, md Immunohistochemical stains. The results were as follows : 1. A 13.5 mm embryo showed the stomatodeum with dental lamina, maxillary and mandibular processes. Meckel's cartilage appeared in the mandibular arch of a 20.5 mm embryo. New bone formation was bilaterally initiated at the outer side of middle portion of Meckel's cartilage of 22-38 mm embryos. 2. Meckel'cartilage was resorbed at the 15th week fetus. The endochondral ossification was observed where there was direct replacement of cartilage by bone. Meckel'cartilage disappeared and membraneous ossification were observed at the 25th week. 3. Before the appearance of Meckel's cartilage, the expression of type I collagen was moderate at the odontogenic epithelium of maxillary & mandibular process, but mild for the expression of type II collagen. 4. During the appearance of Meckel's cartilage and new bone formation, the immunoactivity of type II collagen was more expressed than type I collagen at the Meckel's cartilage and new bone. 5. During intrarmembranous bone formation, the expression of type II collagen was rare in the bony trabeculae. There was a switch for the expression of collagens from type II to type I during the appearance of Meckel's cartilage.

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Age Estimation by Modified Johanson Method (Johanson 방법을 응용한 연령추정)

  • Lee, Won-Joon;Kim, Byung-Gook;Kim, Jae-Hyung;Lim, Hoi-Soon;Lee, Guem-Sug;Choi, Hong-Ran
    • Journal of Oral Medicine and Pain
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    • v.30 no.2
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    • pp.201-214
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    • 2005
  • Age estimation is fundamental and important in personal identification with forensic medicine and dentistry. Recently, a lot of studies using various part of the body have been done for age estimation. Age estimation with teeth is the most significant method comparing ones with other part of the body. Gustafson method and Johanson method using postmortem teeth have been authorized in accuracy and systemization and used domestically and internationally. The verification of the accuracy in above methods had been tried many times but it is still rare in Korea. Fifty-nine teeth(incisors, canine, premolars and molars) which were extracted due to periodontal diseases or orthodontic problem were collected. Present study is to 1) compare the accuracy of estimated age in applying Gustafson method and Johanson method to the teeth in Korea, 2) compare and analyze the correlation with results using Gustafson method and Johanson method by age, gender, maxilla - mandible and anterior - premolar - molar. Teeth were embedded in resin and sliced and then examined each one using Gustafson method and Johanson method. The results are as follows: 1. Actual age was a significant difference in estimated age by Johanson method. Actual age was a significant correlation in estimated age by Gustafson method and modified Johanson method. Modified Johanson method was more significant than Gustafson method. 2. In estimated age by Gustafson method, Johanson method and modified Johanson method, there was no significance with actual age by location and gender. 3. In estimated age by Gustafson method, Johanson method and modified Johanson method, there was significance with actual age by age group. Finally, Gustafson method and Johanson method can be used in Korea. To make more accurate verification, however, it needs more specimen and postmortem teeth. Johanson equation proposed by himself has to be developed by further studies.

Primary Adenosquamous Carcinoma of the Stomach (위에서 발생한 선-편평세포암종)

  • Cho, Yong-Kwon;An, Ji-Yeong;Hong, Seong-Kweon;Choi, Min-Gew;Noh, Jae-Hyung;Sohn, Tae-Sung;Kim, Sung
    • Journal of Gastric Cancer
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    • v.6 no.1
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    • pp.31-35
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    • 2006
  • Purpose: A primary adenosquamous carcinoma of the stomach is relatively rare, accounting for only about 0.5% of all gastric cancers. However, its histopathologic characteristics are still unclear, and the most appropriate form of therapy has not been established yet. Materials and Methods: We retrospectively reviewed the clinicopathologic features of 8 patients with pathologically confirmed primary adenosquamous carcinomas out of 8,268 patients who underwent gastric cancer surgery at Samsung Medical Center between September 1994 and December 2004. Results: The median age of the 8 patients was 49 ($41{\sim}69$) years, and the male : female ratio was 5 : 3. In 3 patients, the tumor was located at the mid body of the stomach, and in 5 patients, at the lower body or antrum. The tumor sizes were $2.5{\sim}8cm$. Seven patients showed metastases to the regional lymph nodes. The UICC stage distribution were: 5 stage II, 2 stage III, and 1 stage IV. In the stage IV patient, a palliative gastrojejunostomy was performed, and he died 5 months after surgery. Of the 7 patients who underwent a radical gastrectomy and adjuvant chemotheratpy, the median survival was 34 ($12{\sim}66$) months, 2 patients died of cancer recurrence, and 4 patients are being followed up without evidence of recurrence. Conclusion: As for an adenocarcinoma of the stomach, a radical gastrectomy including regional lymph node dissection and postoperative adjuvant therapy should be performed for appropriate treatment of an adenosquamous carcinoma of the stomach.

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A Clinical Analysis on 8 cases of Pulmonary Sclerosing Hemangioma (폐 경화성혈관종 8예에 대한 임상적 고찰)

  • Chang, Jung-Hyun;Kim, Se-Kyu;Kim, Hyung-Jung;Kwon, Seon-Ok;Chung, Kyung-Young;Shin, Dong-Hwan;Lee, Doo-Yun;Ahn, Chul-Min;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.4
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    • pp.384-389
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    • 1993
  • Background: Pulmonary sclerosing hemangioma is rare, but still the second most common benign lung tumor, occurring most1y in middle-aged women. Methods: From January 1985 through April 1993, we experienced eight cases of solitary pulmonary sclerosing hemangioma. Results: Subjects studied were 7 female and 1 male patients. They ranged from 14 to 63 years of age(mean age, 43.8 years) at the time of operation. The patients were frequently asymptomatic and the tumor was often shown to be a large lobulated mass on radiographic examination. The tumor can usually be diagnosed on operation because of its subtle clinical and radiographic presentation. All eight cases were diagnosed intraoperatively. The mean interval between initial radiographic detection and operation was 7.9 months. Out of 8 cases, preoperative impression of benign tumor was made in 4 cases, whereas malignant tumor was suspected in the remaining 4 cases. Enucleation, wedge resection or lobectomy was performed which appropriate in each patient. Conclusion: Surgical removal of the tumor preserving as much lung parenchyma as possible is indicated for proper diagnosis and treatment of this condition.

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