• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1386-1390
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• 2008

Artemisinin, the effective ingredient of Chinese herb Artemisia annua L (Qinghao in Chinese), has been proved to be effective to antimalarial. Herein, a reliable, sensitive and convenient electrochemical method was developed for the determination of artemisinin utilizing the excellent properties of multi-wall carbon nanotube (MWNT). The electrochemical behavior of artemisinin was investigated. It is found that the reduction peak current of artemisinin remarkably increases and the peak potential shifts positively by 240 mV at the MWNT film-modified electrode. These phenomena indicate that the MWNT film exhibits efficient catalytic activity to the electrochemical reduction of artemisinin. The effects of pH value, amount of MWNT, scan rate and accumulation time were examined. The limit of detection (S/N = 3) is as low as 10 $\mu$ g $L^{-1}$. Finally, this newly developed method was used to determine the content of artemisinin in Artemisia annua L.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.5427-5433
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• 2013

5-Azacytidine (5-azaC) was originally identified as an anticancer drug (NSC102876) which can cause hypomethylation of tumor suppressor genes. To assess its effects on runt-related transcription factor 3 (RUNX3), expression levels and the promoter methylation status of the RUNX3 gene were assessed. We also investigated alteration of biologic behavior of esophageal carcinoma TE-1 cells. MTT assays showed 5-azaC inhibited the proliferation of TE-1 cells in a time and dose-dependent way. Although other genes could be demethylated after 5-azaC intervention, we focused on RUNX3 gene in this study. The expression level of RUNX3 mRNA increased significantly in TE-1 cells after treatment with 5-azaC at hypotoxic levels. RT-PCR showed 5-azaC at $50{\mu}M$ had the highest RUNX3-induction activity. Methylation-specific PCR indicated that 5-azaC induced RUNX3 expression through demethylation. Migration and invasion of TE-1 cells were inhibited by 5-azaC, along with growth of Eca109 xenografts in nude mice. In conclusion, we demonstrate that the RUNX3 gene can be reactivated by the demethylation reagent 5-azaC, which inhibits the proliferation, migration and invasion of esophageal carcinoma TE-1 cells.

• Fibers and Polymers
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• 제2권2호
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• pp.51-57
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• 2001

Tissue engineering is one exciting approach to treat patients who need a new organ or tissue. A critical element in this approach is the polymer scaffold, as it provides a space for new tissue formation and mimics many roles of natural extra-cellular matrices. In this review, we describe several design parameters of polymer matrices that can significantly affect cellular behavior, as well as various polymers which are frequently used to date or potentially useful in many tissue engineering applications. Interactions between cells and polymer scaffolds, including specific receptor-ligand interactions, physical and degradation feature of the scaffolds, and delivery of soluble factors, should be considered in the design and tailoring of appropriate polymer matrices to be used in tissue engineering applications, as these interactions control the function and structure of engineered tissues.

• 대한세포병리학회지
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• 제8권1호
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• pp.62-68
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• 1997

Acinic cell carcinoma is a slow-growing solid neoplasm of salivary gland. Although their cytological and histological finding is bland-looking, their biological behavior is unpredictable. We experienced two cases of acinic cell carcinoma of the salivary gland diagnosed by fine needle aspiration biopsy and confirmed by tissue examination. They showed different clinical courses. We compared their cytologic and histologic findings. The first case was a right preauricular mass in a 58 year-old female of 3 years duration. The cytologic smear revealed sheets or small clusters of monotonous cells mimicking normal serous acinar cells with little cellular pleomorphism. She underwent superficial parotid lobectomy. The tumor was a well demarcated 1.5cm sized nodular mass without infiltration into surrounding parenchyme. The second case was a left submandibular mass in a 23 year-old male of 4 years duration. The smear showed more severe pleomorphism of the tumor cells than those of previous case. Excisional biopsy was done. The excised tumor was $5.5{\times}3.5{\times}3cm$ sized multilobulated solid mass with invasion into surrounding parenchyme. The tumor recurred after 20months, thus total excision of the mass and modified radical neck dissection was carried out. From the above findings, cytologic atypism, infiltrative growth pattern and type of initial therapy may be correlated with biologic behavior.

• 대한두경부종양학회지
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• 제17권2호
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• pp.210-215
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• 2001

저자들은 약 4년에 걸친 주타액선 종양에 대한 치료 경험을 통하여, 성공적인 치료를 위한 필요조건으로 다음과 같은 내용들을 고려하여야 할 것으로 생각하였다. 즉 타액선 종양은 다양한 조직학적 특징과 임상 경과를 보이는 질환군이므로 수술 전 세침흡인생검 등에 의한 정확한 병리조직학적 진단의 뒷받침이 필수적이라는 점이다. 또한 악성 종양의 경우, 질병분류 및 병기설정 방식이 완전히 통일되어 있지 아니한 상황에서 특정 질환의 특정 병기에 한 가지 치료방법을 고집하기보다는 다양한 종류의 치료를 복합적으로 사용하는 데에 적극적일 필요가 있다고 생각하였다. 특히 예후에 부정적인 영향을 미치는 요소를 가지고 있을 경우에는 적극적인 외과적 절제 및 수술 후 방사선 치료 등을 통하여 생존율을 높이는데 관심을 기울여야 할 것으로 생각되었다. 더 나아가 절개선 등 수술흔이 가지는 미용적 문제점 등도 고려하여 전체적인 치료의 만족도를 향상시키는데 기여해야 할 것으로 생각하였다.

• Journal of Gastric Cancer
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• 제9권3호
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• pp.71-77
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• 2009

내시경 절제술은 림프절 전이의 위험도가 낮은 조기위암에 대한 근치적 국소 치료로 받아들여지고 있다. 최근 조기위암의 림프절 전이에 대한 연구결과들과 내시경 수기 및 부속기구의 발전에 기초하여 내시경 절제의 적용 범위는 확대되는 추세이다. 현재 조기위암의 내시경 절제의 확대 적응증으로는 궤양이 동반되지 않는 경우의 점막암이나, 궤양이 동반된 3 cm 이하의 점막암, 궤양이 없는 3 cm 이하의 미분화 점막암, 3 cm 이하의 궤양을 동반하지 않은 분화가 좋은 미세점막하암으로 림프혈관 침범이 없는 경우이다. 이 중 미분화암은 분화가 좋은 암과 비교하여 다른 생물학적 행태를 가진다는 관점에서 내시경 절제의 확대 적응증으로 포함하는 것에 있어 논란이 있는 상태이다. 따라서, 본 종설에서는 미분화 조기위암의 생물학적 행태와 내시경 절제술 결과에 기초하여 미분화 조기위암에서의 내시경 절제술 적용에 관하여 논해보고자 한다.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1993년도 제27차 학술대회 초록집
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• pp.85-85
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• 1993

후두 편평세포암은 종양세포의 생물학적 특성과 발생부위별 미세환경이 다르기 때문에 임상적 병기만으로 예후를 추정하는 것은 다소 문제점이 있다. 이에 저자들은 종양세포의 유전정보에 의한 증식능이 예후와 연관성이 있는지 규명하고자 EGFR, p53 단백 및 pRB의 표현양상을 후두 편평세포암 40례의 임상적 특성과 비교 검토하여 다음과 같은 성적을 얻었다. 1. p53 단백의 양성 표현율은 임상적 병기, 원발병소의 병기, 경부 림프전이절의 병기, 병리조직학적 분화도, 재발이나 원격전이 흑은 이차암이 있었던 경우와 연관성이 높았다. 2. pRB의 음성 표현율은 침습성이 강한 성문상분, 임상적 병기, 원발병소의 병기, 병리 조직학적 분화도, 재발이나 원격전이 혹은 이차암, 치료에 실패한 경우와 연관성이 높았다. 3. 3년생존율은 p53의 양성표현율과 관계가 있었다. 4. EGFR은 특별한 상관관계가 없었다. 이상의 결과로 보아 p53 단백과 pRB의 암억제유전자 단백의 면역조직화학적 염색을 통한 표현양상은 후두 편평세포암의 생물학적인 특성을 잘 반영하고 있을 뿐만 아니라 종양 즉 인자들과 밀접한 상관관계가 있어 후두 편평세포암의 악성도를 예측하는데 도움을 주는 예후인자로서 적용시킬 수 있을 것으로 생각된다.

• 대한치과보철학회지
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• 제43권6호
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• pp.751-763
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• 2005

Statement of problem. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. The surface quality of the implant depends on the chemical, physical, mechanical and topographical properties of the surface. The different properties will interact with each other and a change in thickness of the oxide layer may also result in a change in surface energy, the surface topography and surface, chemical composition. However, there is limited the comprehensive study with regard to changed surface and biologic behavior of osteoblast by anodization. Purpose of study. The aim of this study was to analyze the characteristics of an oxide layer formed and to evaluate the cellular biologic behaviors on titanium by anodic oxidation (anodization) by cellular proliferation, differentiation, ECM formation and gene expression. And the phospholipase activity was measured on the anodized surface as preliminary study to understand how surface properties of Ti implant are transduced into downstream cellular events. Methods and Materials. The surface of a commercially pure titanium(Grade 2) was modified by anodic oxidation. The group 1 samples had a machined surface and other three experimental specimens were anodized under a constant voltage of 270 V(Group 2), 350 V(Group 3), and 450 V(Group 4). The specimen characteristics were inspected using the following five categories; the surface morphology, the surface roughness, the thickness of oxide layer, the crystallinity, and the chemical composition of the oxide layer. Cell numbers were taken as a marker for cell proliferation. While the expression of alkaline phosphatase and Runx2 (Cbfa1) was used as early differentiation marker for osteoblast. The type I collagen production was determined, which constitutes the main structural protein of the extracellular matrix. Phospholipase $A_2$ and D activity were detected. Results. (1) The anodized titanium had a porous oxide layer, and there was increase in both the size and number of pores with increasing anodizing voltage. (2) With increasing voltage, the surface roughness and thickness of the oxide film increased significantly (p<0.01), the $TiO_2$phase changed from anatase to rutile. During the anodic oxidization, Ca and P ions were more incorporated into the oxide layer. (3) The in vitro cell responses of the specimen were also dependant on the oxidation conditions. With increasing voltage, the ALP activity, type I collagen production, and Cbfa 1 gene expression increased significantly (p<0.01), while the cell proliferation decreased. (4) In preliminary study on the relation of surface property and phospholipase, PLD activity was increased but $PLA_2$ activity did not changed according to applied voltage. Conclusion. The anodized titanium shows improved surface characteristics than the machined titanium. The surface properties acquired by anodization appear to give rise more mature osteoblast characteristics and might result in increased bone growth, and contribute to the achievement of a tight fixation. The precise mechanism of surface property signaling is not known, may be related to phospholipase D.

• 생물정신의학
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• 제20권4호
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• pp.129-135
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• 2013

Aggression can be defined as 'behavior intended to harm another' which can be seen both from humans and animals. However, trying to understand aggression in a simplistic view may make it difficult to develop an integrated approach. So, we tried to explain aggression in a multidisciplinary approach, affected by various factors such as neuroanatomical structures, neurotransmitter, genes, and sex hormone. Parallel with animal models, human aggression can be understood with two phenomena, offensive aggression and defensive aggression. Neurobiological model of aggression give a chance to explain aggression with an imbalance between prefrontal regulatory influences and hyper-reactivity of the subcortical areas involved in affective evaluation, finally in an aspect of brain organization. Serotonin and GABA usually inhibit aggression and norepinephrine while glutamate and dopamine precipitate aggressive behavior. As there is no one gene which has been identified as a cause of aggression, functions between gene to gene interaction and gene to environment interaction are being magnified. Contributions of sex hormone to aggression, especially molecular biologic interaction of testosterone and regulation of estrogen receptor have been emphasized during the research on aggression. This multidisciplinary approach on aggression with types, neurochemical bases, and animal models can bring integrated interpretation on aggression.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제12권1호
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• pp.121-126
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• 1990

Primary squamous cell carcinoma occuring in the salivary glands involves a grave prognosis since the tumor exhibit infiltrative properties, metastasizes early and recurs readily. But it is so rare that the clinician may see only a few in a lifetime of practice. The following report describes a case of primary squamous cell carcinoma arising from the submaxillary gland treated by combined therapy including surgery, radiotherapy and hyperthermia. The biologic behavior of the tumor was quite abnormal that immediate recurrence was noticed in two weeks after surgery. The progress was dismal and the disease became overwhelming before long.