• Korean Journal of Radiology
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• 제22권9호
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• pp.1514-1524
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• 2021

Objective: To develop a radiomics risk score based on dynamic contrast-enhanced (DCE) MRI for prognosis prediction in patients with glioblastoma. Materials and Methods: One hundred and fifty patients (92 male [61.3%]; mean age ± standard deviation, 60.5 ± 13.5 years) with glioblastoma who underwent preoperative MRI were enrolled in the study. Six hundred and forty-two radiomic features were extracted from volume transfer constant (K^trans), fractional volume of vascular plasma space (V_p), and fractional volume of extravascular extracellular space (V_e) maps of DCE MRI, wherein the regions of interest were based on both T1-weighted contrast-enhancing areas and non-enhancing T2 hyperintense areas. Using feature selection algorithms, salient radiomic features were selected from the 642 features. Next, a radiomics risk score was developed using a weighted combination of the selected features in the discovery set (n = 105); the risk score was validated in the validation set (n = 45) by investigating the difference in prognosis between the "radiomics risk score" groups. Finally, multivariable Cox regression analysis for progression-free survival was performed using the radiomics risk score and clinical variables as covariates. Results: 16 radiomic features obtained from non-enhancing T2 hyperintense areas were selected among the 642 features identified. The radiomics risk score was used to stratify high- and low-risk groups in both the discovery and validation sets (both p < 0.001 by the log-rank test). The radiomics risk score and presence of isocitrate dehydrogenase (IDH) mutation showed independent associations with progression-free survival in opposite directions (hazard ratio, 3.56; p = 0.004 and hazard ratio, 0.34; p = 0.022, respectively). Conclusion: We developed and validated the "radiomics risk score" from the features of DCE MRI based on non-enhancing T2 hyperintense areas for risk stratification of patients with glioblastoma. It was associated with progression-free survival independently of IDH mutation status.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2005년도 추계학술대회 및 한일 식물생명공학 심포지엄
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• pp.106-111
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• 2005

For breeding of a new rootstock for eggplant production, somatic hybrids between two species, Solanum integrifolium and S. sanitwongsei were obtained through protoplast fusion. The former species has been commonly used for rootstock for eggplant production in Japan. Eggplants on these rootstocks are more productive than ungrafted plants, but are susceptible to bacterial wilt caused Ralstonia solanacearum. While the latter species is resistant, the growth of eggplants on this rootstock is rather slow and low yield. Protoplast of both species were isolated from cotyledons, and inactivated with iodoacetamide or UV-irradiation, then fused electrically. The fused products were then cultured. Regenerated plantlets were then transplanted on soil then maintained in a green house. The plants were classified into four groups. Those in the first group showed morphological characters intermediate of the parentalspecies. The plants bore fruit with viable seeds. The plants showed a chromosome number of 2n=48, the sum of those of the parental species, and are suggested to be symmetric fusion products. While plants in the other groupswas less vigorous and showed chromosome number 2n= 68 to 72 suggesting asymmetric fusion products by genomic in situ hybridization(GISH). Isozyme pattern of shikimate dehydrogenase (SKDH; EC 1.1.1.25), isocitrate dehydrogenase (IDH; EC 1.1.1.41) and phosphoglucomutase (PGM; EC 2.7.5.1) showed that 24 regenerated plants in three groups were somatic hybrids. Analysis of random amplified polymorphic DNA (RAPD) showed that 43 S. integrifolium-specific and 57 S. sanitwongsei-specific bands were all found in 24 plants. Both somatic hybrids and its S1 plants were found to be resistant to bacterial wilt, and eggplant grafted these plants using for rootstocks were more productive than grafted mother plants. Now, S1 progenies are used for commercial eggplant production in Osaka Prefecture.

• Journal of Microbiology and Biotechnology
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• 제18권8호
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• pp.1368-1376
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• 2008

In our previous study, the expression of active H-ferritins in Saccharomyces cerevisiae was found to reduce cell growth and reactive oxygen species (ROS) generation upon exposure to oxidative stress; such expression enhanced that of high-affinity iron transport genes (FET3 and FTR1). The results suggested that the recombinant cells expressing H-ferritins induced cytosolic iron depletion. The present study analyzes metabolic changes under these circumstances via proteomic methods. The YGH2 yeast strain expressing A-ferritin, the YGH2-KG (E62K and H65G) mutant strain, and the YGT control strain were used. Comparative proteomic analysis showed that the synthesis of 34 proteins was at least stimulated in YGH2, whereas the other 37 proteins were repressed. Among these, the 31 major protein spots were analyzed via nano-LC/MS/MS. The increased proteins included major heat-shock proteins and proteins related to endoplasmic reticulum-associated degradation (ERAD). On the other hand, the proteins involved with folate metabolism, purine and methionine biosynthesis, and translation were reduced. In addition, we analyzed the insoluble protein fractions and identified the fragments of Idh1p and Pgk1p, as well as several ribosomal assembly-related proteins. This suggests that intracellular iron depletion induces imperfect translation of proteins. Although the proteins identified above result from changes in iron metabolism (i.e., iron deficiency), definitive evidence for iron-related proteins remains insufficient. Nevertheless, this study is the first to present a molecular model for iron deficiency, and the results may provide valuable information on the regulatory network of iron metabolism.

• 한국산림과학회지
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• 제78권4호
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• pp.345-359
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• 1989

경북북부(慶北北部)와 남부지방(南部地方)소나무는 외부형태적(外部形態的)으로 차이(差異)가 있으므로 소나무 16개집단(個集團)과 곰솔 5개집단(個集團)의 동위효소(同位酵素) IDH, ME, PGI, ADH, GOT 및 LAP에 의한 종자(種子)의 megagametophyte tissue로 집단간(集團間)의 변이(變異)를 조사(調査)하였다.1. 6개(個)의 동위효소(同位酵素)에서 소나무는 13개(個)의 유전자좌중(遺傳子座中) 변이(變異)가 있는 8개(個) 유전자좌(遺傳子座)에서 24개(個)의 대립유전자(對立遺傳子) 변이(變異)가 있었고, 곰솔은 13개(個) 유전자좌중(遺傳子座中) 변이(變異)가 있는 6개(個) 유전자좌(遺傳子座)에서 18개(個)의 대립유전자(對立遺傳子)가 변이(變異)를 나타냈다. 2. 소나무의 유전자형(遺傳子型) 빈도(頻度)는 동위효소(同位酵素)에 따라 다소 차이(差異)는 있으나 대체로 Hardy-Weinberg의 평형법칙(平衡法則)을 따르고 있으며, 평형법칙(平衡法則)을 따르지 않는 일부집단(一部集團)은 fixation index 값이 높고 동형접합체(同型接合體)의 발생빈도(發生頻度)가 기대치(期待値)보다 높게 나타났다. 3. 소나무에서 상주(尙州), 영주(榮州) 및 봉화집단(奉化集團)을 제외(除外)하고 genetic distance에 의한 집단간(集團間)의 차이(差異)가 없었으나, 경북(慶北)의 북부지방(北部地方)과 태백산맥(太白山脈)의 소나무가 같은 group에 속하고 내륙지방(內l陸地方)인 성주(星州), 의성(義城) 및 금능(金陵)같은 group에 속하며, 경주(慶州)와 백암(白巖)은 각각(各各) 다른 group으로 구분(區分)되었다. 4. 외부형태적(外部形態的)으로 차이(差異)가 있는 경북(慶北) 북부지방(北部地方)과 남부지방(南都地方)의 소나무는 동위효소(同位酵素)에 의한 변이(變異)로서는 뚜렷한 차이점(差異點)을 찾아 볼 수가 없었다. 5. 소나무에서 한 개체당(個體當) 이형접합체(異型接合體)의 유전자좌(遺傳子座) 빈도(頻度)는 ME-A 및 ADH-B locus에서, 곰솔에서는 ADH-B, LAP-B 및 PGI-B에서 가장 높게 나타났으며, 그외(外) locus에서는 동형접합체(同型接合體)의 빈도(頻度)가 높게 나타났다.

• 한국자원식물학회지
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• 제19권1호
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• pp.76-82
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• 2006

우리나라 고산 지역에 제한적으로 자생하는 희귀 유전자원인 눈향나무(Juniperus chinensis var. sargentii HENRY)의 설악산 및 한라산 집단을 대상으로 동위효소 분석에 의한 유전적 다양성을 조사하였다. 총 7개 동위효소에서 11개의 재현성 있는 유전자좌가 분석되었으며, 이중 Mdh-1, Mdh-2, Mdh-3 및 Pig-1 유전자좌를 제외한 7개 유전자좌에서 다형성이 관찰되었다. 분석된 두 집단의 유전변이량은 각각 A=2.2, $A_e=1.61,\;P_{95}=54.5,\;H_{o}=0.179,\;H_e=0.287$(설악산 집단)과 A=2.1, $A_e=1.48,\;P_{95}=63.6,\;H_{o}=0.270,\;H_e=0.250$(한라산 집단)으로 국내 타 침엽수종으로부터 동위효소 분석을 통해 추정된 유전변이량에 비해 다소 높은 경향을 보였으며, 분석 집단간 유전적 분화 정도는 그리 높지 않은 것으로 나타났다($F_{ST}=0.039$). 설악산 집단의 경우 이형접합도의 관찰치가 기대치에 비해 매우 낮았으며 근교계수 값이 매우 높게 나타나(F=0.376), 전반적으로 근친교배 또는 유전적 부동의 영향을 많이 받고 있는 것으로 추정되었다. 이는 설악산 눈향나무 집단의 분포 면적이나 개체수가 한라산 집단에 비해 매우 적기 때문인 것으로 추정되며, 향후 설악산 집단의 보존을 위한 보다 적극적인 노력이 필요한 것으로 사료된다.