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Double-processed ginseng berry extracts enhance learning and memory in an Aβ42-induced Alzheimer's mouse model (Aβ42로 유도된 알츠하이머 마우스 모델에서 이중 가공 인삼열매 추출물의 학습 및 기억 손실 개선 효과)

  • Jang, Su Kil;Ahn, Jeong Won;Jo, Boram;Kim, Hyun Soo;Kim, Seo Jin;Sung, Eun Ah;Lee, Do Ik;Park, Hee Yong;Jin, Duk Hee;Joo, Seong Soo
    • Korean Journal of Food Science and Technology
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    • v.51 no.2
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    • pp.160-168
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    • 2019
  • This study aimed to determine whether double-processed ginseng berry extract (PGBC) could improve learning and memory in an $A\hat{a}42$-induced Alzheimer's mouse model. Passive avoidance test (PAT) and Morris water-maze test (MWMT) were performed after mice were treated with PGBC, followed by acetylcholine (ACh) measurement and glial fibrillary acidic protein (GFAP) detection for brain damage. Furthermore, acetylcholinesterase (AChE) activity and choline acetyltransferase (ChAT) expression were analyzed using Ellman's and qPCR assays, respectively. Results demonstrated that PGBC contained a high amount of ginsenosides (Re, Rd, and Rg3), which are responsible for the clearance of $A{\hat{a}} 42$. They also helped to significantly improve PAT and MWMT performance in the $A{\hat{a}} 42-induced$ Alzheimer's mouse model when compared to the normal group. Interestingly, ACh and ChAT were remarkably upregulated and AChE activities were significantly inhibited, suggesting PGBC to be a palliative adjuvant for treating Alzheimer's disease. Altogether, PGBC was found to play a positive role in improving cognitive abilities. Thus, it could be a new alternative solution for alleviating Alzheimer's disease symptoms.

The Study of CYFRA 21-1 and Epidermal Growth Factor Receptor Levels in Cancer Tissue of Bronchogenic Carcinoma Patients (폐암환자의 암조직내 CYFRA 21-1과 Epidermal Growth Factor Receptor의 측정치에 대한 연구)

  • 김대연;김송명
    • Journal of Chest Surgery
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    • v.30 no.9
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    • pp.854-861
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    • 1997
  • CYPRA 21-1 is known to be a cytokeratin 19 fragment, and it can be detected by using two specific monoclonal antibodies (KS 19-1 and BM 19-21) and can be clinically applied as a useful circulating tumor marker The epidermal growth factor receptor (EGF-R) expression was evaluated and characterized by its tyrosine protein kinase activity and by its ligand-stimulated autophosphorylation, a property shared with other peptide growth factor receptors. Autocrine or para'urine action was initiated by a growth factor, or by a transforming growth factor o, which had an extensive homology with EGP and which also stimulated tyrosine kinase activity on the EGF-R. The CYFRA 21-1 and the EGF-R levels in 30 patients with primary lung tumors were investigated. There were 24 patients with squamous cell carcinomas and 6 patients with adenocarcinomas. Specimen 5 mm3 in size were sampled at three different locations ; the main lesion, the boundary between the lesion and the unaffected tissue, and the unaffected tissue of the patients. The results were as follows 1. The CYPRA 21-1 concentration in the cancer boundary, the most malignant region,(348.6 : 89.9 ng/ml) was the lowest value. The CYFRA 21-1 concentration in unaffected tissue,(718.4$\pm$77.8 ng/ml) was higher than that in the main lesion. which had intact cellularity. 2. The EGF-R concentration in the main lesion was higher than that in the unaffected tissue, and the EGF-R concentration in a squamous cell cacinoma was higher than that in an adenocarcinoma. also, the EGF-R concentration in the cancer b undary was highest at stage 1, ll. The EGF-R concentration was higher in the main cancer lesion that in the unaffected tissue at stage 111, IV. 3. The CYFRA 21-1 was a cytoplasmic skeleton and the EGF-R was a cell-wall component; there was no correlation. In conclusion, CYFRA 21-1 was abundant in the cytoplasm but had a higher concentration in the unaffected tissue than in the main cancer lesion. The CYFRA 21-1 concentration of the tissue did not reflect the amount of cancer activity, the EGP-R was located in the cell membrane, the level of tissue that reflects cancer activity, so the main cancer lesion had a higher concentration than the unaffected tissue. CYFRA 21-1 is not a useful tumor maker at the tissue level. Because the EGF-R concentration re(looted the cancer activity, its a useful tumor marker for lung cancer.

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The relationship between catechol-O-methyltransferase gene polymorphism and coronary artery abnormality in Kawasaki disease (가와사키병의 관상동맥 이상과 catechol-O-methyltransferase 유전자의 단일염기다형성)

  • Lee, Hyo Jin;Lee, Myung Sook;Kim, Ji Sook;Kim, Eun Ryoung;Kang, Sung Wook;Kim, Soo Kang;Chung, Joo Ho;Yoon, Kyung Lim;Han, Mi Young;Cha, Seong Ho
    • Clinical and Experimental Pediatrics
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    • v.52 no.1
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    • pp.87-92
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    • 2009
  • Purpose : Many gene polymorphisms are associated with coronary artery abnormalities in Kawasaki disease. Catechol-O- methyltransferase (COMT) plays an important role in the metabolism of catecholamines, catechol estrogen, and catechol drugs. Polymorphisms of the COMT gene are reported to be associated with myocardial infarction and coronary artery abnormalities. The aim of this study was to evaluate the relationship between COMT gene polymorphisms and coronary artery abnormalities in Kawasaki disease patients. Methods : One hundred and one Korean children with Kawasaki disease and 306 healthy Korean control subjects were enrolled in this study. The polymorphisms of the COMT gene were analyzed by direct sequencing. Results : There were no differences in the genotype and allelic frequency of the rs4680 and rs769224 polymorphic sites between Kawasaki disease and control subjects. Further, no significant difference was found in the rs4680 polymorphism between patients with coronary artery abnormalities and patients without coronary artery abnormalities (codominant P=0.32, dominant P=0.74, recessive P=0.13). However, the distribution of the rs769224 polymorphism was significantly different between patients with coronary artery abnormalities and patients without coronary artery abnormalities (codominant P= 0.0077, dominant P=0.0021, recessive P=0.16). Conclusion : Our results indicate that the polymorphisms of the rs769224 gene might be related to the development of coronary artery abnormalities in Kawasaki disease.

Effect of Temperature on Growth and Related Gene Expression in Alternative Type Wheat Cultivars (양절형 밀 생장에 대한 온도의 영향과 유전자 발현 양상)

  • Heo, Ji Hye;Seong, Hye Ju;Yang, Woon Ho;Jung, Woosuk
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.4
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    • pp.384-394
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    • 2019
  • We have investigated the effects of ambient temperature on the growth of wheat in Korea. The differences in the growth phase of wheat were compared according to the temperature treatment. The productive tiller number and dry weight were decreased in a plot under a higher temperature treatment. We found that the growth of Jinpum was different from that of the alternative wheat cultivars, which were bred in Korea, at 50 days after treatment. While the Jinpum wheat grown at 17℃ showed vegetative stage growth, that grown in the 23℃ growth chamber entered the heading and flowering stage. The differences in the expression of 16 genes known to be involved in high-temperature responses were checked by using Jinpum wheat 50 days after two temperature treatments (17℃ and 23℃), which showed apparent differences in expression between the higher and lower temperatures during the growth phase. In the 23℃ treatment samples, the genes with increased expression were HSP70, HSP101, VRN2, ERF1, TAA1, YUCCA2, GolS, MYB73, and Histone H2A, while the genes with decreased expression were VRN-A1, DREB2A, HsfA3, PIF4, PhyB, HSP17.6CII, rbcL, and MYB73. YUCCA2, HSP101, ERF1, and VRN-A1 showed a significant difference in gene expression between lower- and higher-temperature conditions. Overall, combining the means of the expression of various genes involved in thermosensing, vernalization, and abiotic stresses, it is possible to conclude that different sets of genes are involved in vernalization and summer depression of wheat under long term, high ambient temperature conditions.

Decitabine in the Treatment of Acute Myeloid Leukemia and Myelodysplastic Syndromes, Which Combined with Complex Karyotype Respectively

  • Gao, Su;Li, Zheng;Fu, Jian-Hong;Hu, Xiao-Hui;Xu, Yang;Jin, Zheng-Ming;Tang, Xiao-Wen;Han, Yue;Chen, Su-Ning;Sun, Ai-Ning;Wu, De-Pei;Qiu, Hui-Ying
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6627-6632
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    • 2015
  • Background: We conducted a study exploring the clinical safety and efficacy of decitabine in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS), combined with a complex karyotype. Materials and Methods: From April 2009 to September 2013, a total of 35 patients with AML/MDS combined with a complex karyotype diagnosed in the First Affiliated Hospital of Soochow University were included for retrospective analysis. All patients were treated with decitabine alone ($20mg/m^2$ daily for 5 days) or combination AAG chemotherapy (Acla 20mg qod*4d, Ara-C $10mg/m^2$ q12h*7d, G-CSF $300{\mu}g$ qd, the dose of G-CSF adjusted to the amount in blood routinely). Results: In 35 patients, 15 exhibited a complete response (CR), and 6 a partial response (PR), the overall response rate (CR+PR) being 60% (21 of 35). Median disease-free survival was 18 months and overall survival was 14 months. In the 15 MDS patients with a complex karyotype, the CR rate was 53.3% (8 of 15); in 20 AML patients with complex karyotype, the overall response rate was 65% (13 of 20). The response rate of decitabine alone (22 cases) was 56.5% (13 of 22), while in the combination chemotherapy group (13 cases), the effective rate was 61.5% (8 of 13)(P>0.05). There are 15 patients with chromosome 7 aberration, after treatment with decitabine, 7 CR, 3 PR, overall response rate was 66.7% (10 of 15). Of 18 patients with 3 to 5 kinds of chromosomal abnormalities, 66.7% demonstrated a response; of 17 with more than 5 chromosomal abnormalities, 52.9% had a response. In the total of 35 patients, with one course (23 patients) and ${\geq}$two courses (12 patients), the overall response rate was 40.9% and 92.3% (P<0.05). Grade III to IV hematological toxicity was observed in 27 cases (75%). Grade III to IV infections were clinically documented in 7 (20%). Grades I to II non-hematological toxicity were infections (18 patients), haematuria (2 patients), and bleeding (3 patients). With follow-up until September 2013, 7 patients were surviving, 18 had died and 10 were lost to follow-up. In the 6 cases who underwent allogeneic hematopoietic stem cell transplantation (HSCT) all were still relapse-free survivors. Conclusions: Decitabine alone or combination with AAG can improve outcome of AML/MDS with a complex karyotype, there being no significant difference decitabine in inducing remission rates in patients with different karyotype. Increasing the number of courses can improve efficiency. This approach with fewer treatment side effects in patients with a better tolerance should be employed in order to create an improved subsequent chance for HSCT.

The Gains To Bidding Firms' Stock Returns From Merger (기업합병의 성과에 영향을 주는 요인에 대한 실증적 연구)

  • Kim, Yong-Kap
    • Management & Information Systems Review
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    • v.23
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    • pp.41-74
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    • 2007
  • In Korea, corporate merger activities were activated since 1980, and nowadays(particuarly since 1986) the changes in domestic and international economic circumstances have made corporate managers have strong interests in merger. Korea and America have different business environments and it is easily conceivable that there exists many differences in motives, methods, and effects of mergers between the two countries. According to recent studies on takeover bids in America, takeover bids have information effects, tax implications, and co-insurance effects, and the form of payment(cash versus securities), the relative size of target and bidder, the leverage effect, Tobin's q, number of bidders(single versus multiple bidder), the time period (before 1968, 1968-1980, 1981 and later), and the target firm reaction (hostile versus friendly) are important determinants of the magnitude of takeover gains and their distribution between targets and bidders at the announcement of takeover bids. This study examines the theory of takeover bids, the status quo and problems of merger in Korea, and then investigates how the announcement of merger are reflected in common stock returns of bidding firms, finally explores empirically the factors influencing abnormal returns of bidding firms' stock price. The hypotheses of this study are as follows ; Shareholders of bidding firms benefit from mergers. And common stock returns of bidding firms at the announcement of takeover bids, shows significant differences according to the condition of the ratio of target size relative to bidding firm, whether the target being a member of the conglomerate to which bidding firm belongs, whether the target being a listed company, the time period(before 1986, 1986, and later), the number of bidding firm's stock in exchange for a stock of the target, whether the merger being a horizontal and vertical merger or a conglomerate merger, and the ratios of debt to equity capital of target and bidding firm. The data analyzed in this study were drawn from public announcements of proposals to acquire a target firm by means of merger. The sample contains all bidding firms which were listed in the stock market and also engaged in successful mergers in the period 1980 through 1992 for which there are daily stock returns. A merger bid was considered successful if it resulted in a completed merger and the target firm disappeared as a separate entity. The final sample contains 113 acquiring firms. The research hypotheses examined in this study are tested by applying an event-type methodology similar to that described in Dodd and Warner. The ordinary-least-squares coefficients of the market-model regression were estimated over the period t=-135 to t=-16 relative to the date of the proposal's initial announcement, t=0. Daily abnormal common stock returns were calculated for each firm i over the interval t=-15 to t=+15. A daily average abnormal return(AR) for each day t was computed. Average cumulative abnormal returns($CART_{T_1,T_2}$) were also derived by summing the $AR_t's$ over various intervals. The expected values of $AR_t$ and $CART_{T_1,T_2}$ are zero in the absence of abnormal performance. The test statistics of $AR_t$ and $CAR_{T_1,T_2}$ are based on the average standardized abnormal return($ASAR_t$) and the average standardized cumulative abnormal return ($ASCAR_{T_1,T_2}$), respectively. Assuming that the individual abnormal returns are normal and independent across t and across securities, the statistics $Z_t$ and $Z_{T_1,T_2}$ which follow a unit-normal distribution(Dodd and Warner), are used to test the hypotheses that the average standardized abnormal returns and the average cumulative standardized abnormal returns equal zero.

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Applicability of plate tectonics to the post-late Cretaceous igneous activities and mineralization in the southern part of South Korea( I ) (한국남부(韓國南部)의 백악기말(白堊紀末) 이후(以後)의 화성활동(火成活動)과 광화작용(鑛化作用)에 대(對)한 판구조론(板構造論)의 적용성(適用性) 연구(硏究)( I ))

  • Min, Kyung Duck;Kim, Ok Joon;Yun, Suckew;Lee, Dai Sung;Joo, Sung Whan
    • Economic and Environmental Geology
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    • v.15 no.3
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    • pp.123-154
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    • 1982
  • Petrochemical, K-Ar dating, Sand Rb/Sr isotopes, metallogenic zoning, paleomagnetic and geotectonic studies of the Gyongsang basin were carried out to examine applicability of plate tectonics to the post-late Cretaceous igneous activity and metallogeny in the southeastern part of Korean Peninsula. The results obtained are as follows: 1. Bulgugsa granitic rocks range from granite to adamellite, whose Q-Ab-Or triangular diagram indicates that the depth and pressure at which the magma consolidated increase from coast to inland varying from 6 km, 0.5-3.3 kb in the coastal area to 17 km, 0.5-10 kb in the inland area. 2. The volcanic rocks in Gyongsang basin range from andesitic to basaltic rocks, and the basaltic rocks are generally tholeiitic in the coastal area and alkali basalt in the inland area. 3. The volcanic rocks of the area have the initial ratio of Sr^{87}/Sr^{86} varying from 0.706 to 0.707 which suggests a continental origin; the ratio of Rb/Sr changing from 0.079-0.157 in the coastal area to 0.021-0.034 in the inland area suggests that the volcanism is getting younger toward coastal side, which may indicate a retreat in stage of differentiation if they were derived from a same magma. The K_2O/SiO_2 (60%) increases from about 1.0 in the coastal area to about 3.0 in the inland area, which may suggest an increase indepth of the Benioff zone, if existed, toward inland side. 4. The K-Ar ages of volcanic rocks were measured to be 79.4 m.y. near Daegu, and 61.7 m.y. near Busan indicating a southeastward decrease in age. The ages of plutonic rocks also decrease toward the same direction with 73 m.y. near Daegu, and 58 m.y. near Busan, so that the volcanism predated the plutonism by 6 m.y. in the continental interior and 4 m.y. along the coast. Such igneous activities provide a positive evidence for an applicability of plate tectonics to this area. 5. Sulfur isotope analyses of sulfide minerals from 8 mines revealed that these deposits were genetically connected with the spacially associated ingeous rocks showing relatively narrow range of ${\delta}^{34}S$ values (-0.9‰ to +7.5‰ except for +13.3 from Mulgum Mine). A sequence of metallogenic zones from the coast to the inland is delineated to be in the order of Fe-Cu zone, Cu-Pb-Zn zone, and W-Mo zone. A few porphyry type copper deposits are found in the Fe-Cu zone. These two facts enable the sequence to be comparable with that of Andean type in South America. 6. The VGP's of Cretaceous and post Cretaceous rocks from Korea are located near the ones($71^{\circ}N$, $180^{\circ}E$ and $90^{\circ}N$, $110^{\circ}E$) obtained from continents of northern hemisphere. This suggests that the Korean peninsula has been stable tectonically since Cretaceous, belonging to the Eurasian continent. 7. Different polar wandering path between Korean peninsula and Japanese islands delineates that there has been some relative movement between them. 8. The variational feature of declination of NRM toward northwestern inland side from southeastern extremity of Korean peninsula suggests that the age of rocks becomes older toward inland side. 9. The geological structure(mainly faults) and trends of lineaments interpreted from the Landsat imagery reveal that NNE-, NWW- and NEE-trends are predominant in the decreasing order of intensity. 10. The NNE-trending structures were originated by tensional and/or compressional forces, the directions of which were parallel and perpendicular respectively to the subduction boundary of the Kula plate during about 90 m.y. B.P. The NWW-trending structures were originated as shear fractures by the same compressional forces. The NEE-trending structures are considered to be priginated as tension fractures parallel to the subduction boundary of the Kula plate during about 70 m.y. B.P. when Japanese islands had drifted toward southeast leaving the Sea of Japan behind. It was clearly demonstrated by many authors that the drifting of Japanese islands was accompanied with a rotational movement of a clock-wise direction, so that it is inferred that subduction boundary had changed from NNE- to NEE-direction. A number of facts and features mentioned above provide a suite of positive evidences enabling application of plate tectonics to the late Cretaceous-early Tertiary igneous activity and metallogeny in the area. Synthesizing these facts, an arc-trench system of continental margin-type is adopted by reconstructing paleogeographic models for the evolution of Korean peninsula and Japan islands. The models involve an extention mechanism behind the are(proto-Japan), by which proto-Japan as of northeastern continuation of Gyongsang zone has been drifted rotationally toward southeast. The zone of igneous activity has also been migrated from the inland in late-Cretaceous to the peninsula margin and southwestern Japan in Tertiary.

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A study of the plan dosimetic evaluation on the rectal cancer treatment (직장암 치료 시 치료계획에 따른 선량평가 연구)

  • Jeong, Hyun Hak;An, Beom Seok;Kim, Dae Il;Lee, Yang Hoon;Lee, Je hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.28 no.2
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    • pp.171-178
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    • 2016
  • Purpose : In order to minimize the dose of femoral head as an appropriate treatment plan for rectal cancer radiation therapy, we compare and evaluate the usefulness of 3-field 3D conformal radiation therapy(below 3fCRT), which is a universal treatment method, and 5-field 3D conformal radiation therapy(below 5fCRT), and Volumetric Modulated Arc Therapy (VMAT). Materials and Methods : The 10 cases of rectal cancer that treated with 21EX were enrolled. Those cases were planned by Eclipse(Ver. 10.0.42, Varian, USA), PRO3(Progressive Resolution Optimizer 10.0.28) and AAA(Anisotropic Analytic Algorithm Ver. 10.0.28). 3fCRT and 5fCRT plan has $0^{\circ}$, $270^{\circ}$, $90^{\circ}$ and $0^{\circ}$, $95^{\circ}$, $45^{\circ}$, $315^{\circ}$, $265^{\circ}$ gantry angle, respectively. VMAT plan parameters consisted of 15MV coplanar $360^{\circ}$ 1 arac. Treatment prescription was employed delivering 54Gy to recum in 30 fractions. To minimize the dose difference that shows up randomly on optimizing, VMAT plans were optimized and calculated twice, and normalized to the target V100%=95%. The indexes of evaluation are D of Both femoral head and aceta fossa, total MU, H.I.(Homogeneity index) and C.I.(Conformity index) of the PTV. All VMAT plans were verified by gamma test with portal dosimetry using EPID. Results : D of Rt. femoral head was 53.08 Gy, 50.27 Gy, and 30.92 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. D of Rt. aceta fossa was 54.86 Gy, 52.40 Gy, 30.37 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. The maximum dose of both femoral head and aceta fossa was higher in the order of 3fCRT, 5fCRT, and VMAT treatment plan. C.I. showed the lowest VMAT treatment plan with an average of 1.64, 1.48, and 0.99 in the order of 3fCRT, 5fCRT, and VMAT treatment plan. There was no significant difference on H.I. of the PTV among three plans. Total MU showed that the VMAT treatment plan used 124.4MU and 299MU more than the 3fCRT and 5fCRT treatment plan, respectively. IMRT verification gamma test results for the VMAT plan passed over 90.0% at 2mm/2%. Conclusion : In rectal cancer treatment, the VMAT plan was shown to be advantageous in most of the evaluation indexes compared to the 3D plan, and the dose of the femoral head was greatly reduced. However, because of practical limitations there may be a case where it is difficult to select a VMAT treatment plan. 5fCRT has the advantage of reducing the dose of the femoral head as compared to the existing 3fCRT, without regard to additional problems. Therefore, not only would it extend survival time but the quality of life in general, if hospitals improved radiation therapy efficiency by selecting the treatment plan in accordance with the hospital's situation.

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Investigating Dynamic Mutation Process of Issues Using Unstructured Text Analysis (부도예측을 위한 KNN 앙상블 모형의 동시 최적화)

  • Min, Sung-Hwan
    • Journal of Intelligence and Information Systems
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    • v.22 no.1
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    • pp.139-157
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    • 2016
  • Bankruptcy involves considerable costs, so it can have significant effects on a country's economy. Thus, bankruptcy prediction is an important issue. Over the past several decades, many researchers have addressed topics associated with bankruptcy prediction. Early research on bankruptcy prediction employed conventional statistical methods such as univariate analysis, discriminant analysis, multiple regression, and logistic regression. Later on, many studies began utilizing artificial intelligence techniques such as inductive learning, neural networks, and case-based reasoning. Currently, ensemble models are being utilized to enhance the accuracy of bankruptcy prediction. Ensemble classification involves combining multiple classifiers to obtain more accurate predictions than those obtained using individual models. Ensemble learning techniques are known to be very useful for improving the generalization ability of the classifier. Base classifiers in the ensemble must be as accurate and diverse as possible in order to enhance the generalization ability of an ensemble model. Commonly used methods for constructing ensemble classifiers include bagging, boosting, and random subspace. The random subspace method selects a random feature subset for each classifier from the original feature space to diversify the base classifiers of an ensemble. Each ensemble member is trained by a randomly chosen feature subspace from the original feature set, and predictions from each ensemble member are combined by an aggregation method. The k-nearest neighbors (KNN) classifier is robust with respect to variations in the dataset but is very sensitive to changes in the feature space. For this reason, KNN is a good classifier for the random subspace method. The KNN random subspace ensemble model has been shown to be very effective for improving an individual KNN model. The k parameter of KNN base classifiers and selected feature subsets for base classifiers play an important role in determining the performance of the KNN ensemble model. However, few studies have focused on optimizing the k parameter and feature subsets of base classifiers in the ensemble. This study proposed a new ensemble method that improves upon the performance KNN ensemble model by optimizing both k parameters and feature subsets of base classifiers. A genetic algorithm was used to optimize the KNN ensemble model and improve the prediction accuracy of the ensemble model. The proposed model was applied to a bankruptcy prediction problem by using a real dataset from Korean companies. The research data included 1800 externally non-audited firms that filed for bankruptcy (900 cases) or non-bankruptcy (900 cases). Initially, the dataset consisted of 134 financial ratios. Prior to the experiments, 75 financial ratios were selected based on an independent sample t-test of each financial ratio as an input variable and bankruptcy or non-bankruptcy as an output variable. Of these, 24 financial ratios were selected by using a logistic regression backward feature selection method. The complete dataset was separated into two parts: training and validation. The training dataset was further divided into two portions: one for the training model and the other to avoid overfitting. The prediction accuracy against this dataset was used to determine the fitness value in order to avoid overfitting. The validation dataset was used to evaluate the effectiveness of the final model. A 10-fold cross-validation was implemented to compare the performances of the proposed model and other models. To evaluate the effectiveness of the proposed model, the classification accuracy of the proposed model was compared with that of other models. The Q-statistic values and average classification accuracies of base classifiers were investigated. The experimental results showed that the proposed model outperformed other models, such as the single model and random subspace ensemble model.

A Case of Carbamoyl Phosphate Synthetase 1 Deficiency with Novel Mutations in CPS1 Treated by Liver Cell Transplantation (신생아기에 새로운 CPS1 유전자 돌연변이가 확인되고, 간세포이식 시행 받은 Carbamoyl phosphatase synthetase 1 deficiency 1례)

  • Lee, Jisun;Yang, Aram;Kim, Jinsup;Park, Hyung-Doo;Lee, Sanghoon;Lee, Suk-Koo;Cho, Sung Yoon;Jin, Dong-Kyu
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.17 no.1
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    • pp.31-37
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    • 2017
  • Carbamoyl phosphate synthetase 1 deficiency (CPS1D) is an autosomal recessive disorder of the urea cycle that causes hyperammonemia. Two forms of CPS1D are recognized: a lethal neonatal type and a less severe, delayed-onset type. Neonatal CPS1D cases often present their symptoms within the first days of life. Delayed-onset cases are predominantly adolescents or adults, and infantile delayed-onset cases are rare. Severe hyperammonemia in the neonatal period leads to serious brain damage, coma, and death if not treated promptly. Therefore, early diagnosis and acute treatment are crucial. Despite the improvement of treatments, including continuous hemodialysis, ammonia-lowering agents, and a low-protein diet, the overall outcome of severe forms of hyperammonemia often remains disappointing. As the liver is the only organ in which ammonia is converted into urea, liver transplantation has been considered as an elegant and radical alternative therapy to classical dietary and medical therapies. However, liver transplantation has many disadvantages, such as a considerable risk for technical complications and perioperative metabolic derangement, especially in neonates. Additionally, there is a lack of suitable donor organs in most countries. According to recent studies, liver cell transplantation is a therapeutic option and serves as a bridge to liver transplantation. Here, we report a Korean CPS1D patient with novel mutations in CPS1 who was treated by liver cell transplantation after being diagnosed in the neonatal period and showed a good neurodevelopmental outcome at the last follow-up at six months of age.

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