• 대한조선학회논문집
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• 제37권4호
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• pp.48-55
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• 2000

선박의 저항을 줄이기 위하여 발생시킨 기포의 거동을 알기 위해, 선체주위의 기포거동에 과한 기초적 연구를 수행하였다. 본 연구에서는 선체주위에 발생된 기포의 거동에 대하여, 기포의 크기와 발생위치를 변화시켜가며 수치계산 및 실험을 수행하여, 선체주위의 기포거동에 관한 특성을 연구하고자 하였다. 기포의 거동방정식은 기포의 부력을 고려한 Kawakita의 것을 사용하였다. 수치계산은 MAC(Marker And Cell)법을 기초로 한 유한차분법(Finite Difference Method)을 사용하였으며, 실험은 Series 60선형에 대하여 회류수조에서 수행되었다. 실험과 계산은 서로 비교하여 보았다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.29-34
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• 2000

This paper describes a numerical study to make clear the characteristics of flow around a high speed catamaran hull advancing on calm water. The simulation is carried out at Froude number of 0.5 with a separation to length rations of 0.2 to 0.5. To simulate the flows, the Navier-Stokes solver is employed in which the free surface condition is included. Computations are performed in a rectangular grid system based grid system based on the Marker & Cell method. For the validation, the computation results are compared with the experiments.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1325-1331
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• 2012

Tumor formation and growth is dictated by a very small number of tumor cells, called cancer stem cells, which are capable of self-renewal. The genesis of cancer stem cells and their resistance to conventional chemotherapy and radiotherapy via mechanisms such as multidrug resistance, quiescence, enhanced DNA repair abilities and anti-apoptotic mechanisms, make it imperative to develop methods to identify and use these cells as diagnostic or therapeutic targets. Aldehyde dehydrogenase 1 (ALDH1) is used as a cancer stem cell marker. In this study, we evaluated ALDH1 expression in CaSki, HeLa and SiHa cervical cancer cells using the Aldefluor method to isolate ALDH1-positive cells. We showed that higher ALDH1 expression correlated with significantly higher rates of cell proliferation, microsphere formation and migration. We also could demonstrate that SiHa-ALDH1-positive cells were significantly more tumorigenic compared to SiHa-ALDH1-negative cells. Similarly, SiHa cells overexpressing ALDH1 were significantly more tumorigenic and showed higher rates of cell proliferation and migration compared to SiHa cells where ALDH1 expression was knocked down using a lentivirus vector. Our data suggested that ALDH1 is a marker of cervical cancer stem cells and expand our understanding of its functional role.

• Ocean and Polar Research
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• 제27권4호
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• pp.397-417
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• 2005

Phytoplankton community structure and distribution pattern in the surface water around the Ieodo Ocean Research Station were investigated during seven cruises carried out from July, 2003 to October, 2004. Samples were analyzed using various tools including a microscope, flow cytometer, and HPLC. Satellite images were used to analyze spatio-temporal phytoplankton biomass distribution. SeaWiFS chlorophyll a (chl a) images showed that spring blooms occurred in April-May near the Ieodo Station, and these waters were under the influence of Changjiang Dilute Water during July-October. Also, during the July-October period, HPLC pigments data showed increasing zeaxanthin concentrations, a marker pigment of cyanobacteria whereas increasing concentrations of various other pigments such as fucoxanthin, peridinin, prasinoxanthia alloxanthin, 19'-hexanoyloxyfucoxanthin and chlorophyll b were noted during spring blooms. Such pigment marker data were consistent with picoplankton data analyzed by flow cytometer and nano-microplankton analyzed by microscope. The pigment-CHEMTAX method was used to drive the phytoplankton group apportioned chi a. Diatoms, chlorophytes, dinoflagellates, and cryptophytes comprised 25.8, 20.7, 15.9, and 14.1%, respectively, of the total chl a in May. Average cyanobacteria concentrations in July-October contributed 25.4% of the total concentration. This was the highest percent contribution and was followed by chlorophytes, diatoms, and prymnesiophytes. This study discusses results from various methods, similarities and differences in the results among those methods, and the application range of the results from different analytical methods. Also, the study reveals a detailed phytolpankton community structure in the waters around the Ieodo Station, and suggests future monitoring considerations in relation to cell morphology, ecology and diversity factors according to taxonomic groups.

• Mass Spectrometry Letters
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• 제8권2호
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• pp.34-38
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• 2017

The purpose of this study was to develop a cocktail approach for the measurement of the permeability of marker compounds, caffeine and propranolol (high permeability), ofloxacin (intermediate), atenolol (low), and quinidine (P-glycoprotein substrate), simultaneously. Then we compared the permeability in Caco-2 cells with that in rat intestinal segments. The difference between individual measurement and cocktail approach was less than 20 %, and the permeabilities of these compounds were similar to those previously reported, suggesting that the cocktail transport study and simultaneous drug analysis were successfully developed and validated in this study. Additionally, in the application of this cocktail method, the permeability of five drugs in rat jejunum was similar to that in ileum but different from that in colon, which was measured using the Ussing chamber system. Moreover, permeability in jejunum and ileum was similar to that in Caco-2 cells. In conclusion, the permeability in Caco-2 cells was equivalent to the permeability in rat jejunum and ileum determined with the Ussing system. Therefore, this newly developed cocktail assay and its application to the Ussing system can be a useful tool for robust and rapid screening for site-specific permeability in rat intestine, thus accelerating the prediction of absorption of new chemical entities.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1996년도 춘계 학술대회논문집
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• pp.85-92
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• 1996

Numerical simulations are made for the three-dimensional flow around a wing in ground effect craft haying the complex geometry. A numerical tool is developed for the primary design of hull and wing shape of practical Wing-In-Ground effect(WIG) stop. The finite-difference method is utilized to descretize the governing equations and pressure field is obtained by using Marker-And-Cell(MAC) method. The air and water flows are simultaneously simulated in the time-marching solution procedure for the Navier-Stokes equation. The porosity technique and the density function are devised for the implementation of the three-dimensional body-boundary and the free-surface conditions, respectively. In this paper, a craft is modeled simply by three blocks containing a wing mounted on a main body horizontally, with the endplate. The numerical calculations of a WIG advancing in a calm water are performed and the WIG-generated wave profiles are also obtained. In the final paper, details of the numerical methods employed for the present study and calculated results are discussed.

• 대한임상검사과학회지
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• 제40권1호
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• pp.41-47
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• 2008

Colorectal carcinoma is occurred frequently to Korean and so ranked the fourth from various cancers. Due to western dietary life, this cancer has been increased continually. Therefore, the study will be needed to find a candidate gene involved in the development and progression of colorectal carcinoma and to diagnose and treatment helpfully. The striking feature from cancer suppressor genes is known for LOH (loss of heterozygosity), which is the method to find allele genetic loss or mutation of cancer cell. The purpose of this study was designed to find a carcinogenic gene from colon cancer using microsatellite marker on 17th and 18th chromosome from 30 subjects. The LOH was investigated in order of D18S59 57% (17/30), TP53CA 50% (15/30), D18S68 47% (14/30), D18S69 43% (13/30). The genetic mutation depends on loci of colorectal carcinoma was shown higher with 2.44 from colon cancer than with 1.25 from right colorectal carcinoma (p<0.032). The genetic mutation with lymph nodes was investigated higher with 2.69 at mutated group than with 1.14 at non-mutated group (p<0.003). At genetic mutated pattern depends on disease stage, there was higher significant difference at III-IV stage 2.50 than that of I-II stage 1.17, respectively (p=0.015). There was no difference at comparison between histological classification and serological CEA increase. The loss on 18q21 found in this study is highly recurrence loci and was observed 43% for Korean with high recurrence. Therefore, LOH is a very useful tool to detect 18q21 loci in clinical application, prior to the treatment of colorectal carcinoma. After the operation of colorectol carcinoma, the efficient application using LOH at operated part tissue which is designed to protect the recurrence as well as its cure will be needed.

• Tuberculosis and Respiratory Diseases
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• 제39권5호
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• pp.400-406
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• 1992

연구배경 : 최근 연구가 활발한 SCC 항원을 이용하여 폐암환자의 진단적 의미, 치료효과 판정, 예후를 예측할 수 있는 지표로써의 가능성을 알아보고자 본 연구를 시행하였다. 방법 : 정상대조군, 양성 폐질환 환자군과 폐암환자에서 SCC 항원을 측정하였으며 폐암 환자를 대상으로 치료전과 치료후 SCC Riabeap radioimmunoassay kit를 이용하여 SCC 항원을 측정하였다. 결과 : 1) SCC 항원치는 편평세포 폐암환자인 경우 $2.26{\pm}1.53\;ng/ml$, 기타 폐암은 $0.62{\pm}0.53\;ng/ml$, 양성 폐질환 환자는 $0.67{\pm}0.38\;ng/ml$, 정상 대조군은 $0.53{\pm}0.36\;ng/ml$ 이었다. 2) SCC 항원이 양성을 보인 편평세포 폐암환자는 42%(5/12)이었고 기타 폐암환자 양성 폐질환환자, 정상 대조군은 1명도 없었다. 3) 편평 세포폐암 환자의 SCC 항원 평균치는 병기에 따라 I기에 $2.07{\pm}1.56\;ng/ml$, $III_a$기는 $5.04{\pm}0.53\;ng/ml$, $III_b$기는 $1.94{\pm}0.7\;ng/ml$, IV기는 $1.07{\pm}0.64\;ng/ml$ 이었다. 4) 치료에 따른 항원역가는, 치료에 반응을 보인 환자에게서 치료 전보다 치료후 유의하게 감소하는 것을 볼 수가 있었다. 결론 : 이상의 결과로 SCC 항원은 편평세포 폐암을 진단하는 보조적인 수단으로서 이용 가능성과 치료에 따른 효과를 판정할 수있는 추적검사 방법으로서의 가능성을 제시하였다.

• Tuberculosis and Respiratory Diseases
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• 제47권6호
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• pp.797-806
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• 1999

연구배경: 소세포 폐암은 진단 당시 약 20% 이상에서 진단 당시 골수전이가 발견됨으로써 초기의 혈행성 전이가 중요한 예후인자일 것으로 추정되고 있다. 따라서 진단 또는 치료당시 기존의 검사수기로는 확인할 수 없었던 미세전이를 확인할 수 있다면 환자의 치료방침 및 예후결정에 유효한 지표가 될 수 있을 것으로 기대되어 왔다. 최근 cytokeratin(CK)-20 이 골수와 같은 조혈기관에서는 발현되지 않으면서 상피세포에서만 발현되는 것으로 알려져서 이 표지자가 소세포 폐암과 같은 상피세포암의 골수 미세전이의 발견에 효과적일 가능성을 사사하고 있다. 방 법: 소세포암세포주인 H209와 정상인의 혈구세포를 대상으로 CK-20 발현을 비교하였고, 소세포 폐암환자의 병기결정을 위한 경사로서 골수천자를 시행하면서 동시에 골수를 수집하여 이로부터 RNA를 수출하여 CK-20에 대한 primer를 이용하여 RT-PCR을 시행하였다. 결 과: H209 세포주에서는 CK-20의 발현이 관찰된 반면, 정상 혈구세포에서는 관찰되지 않아서 CK-20이 조혈세포에서는 발현되지 않고, 상피조직에 서만 특이적으로 발현되는 것으로 생각되었다. 28명의 소세포 폐암환자중 제한기가 11명, 확장기 환자가 17명이었으며, 17명의 확장기 환자가운데 골수조직검사상 골수 침범이 확인되었거나 또는 골주사검사상 전이가 확인된 환자는 7명(41%)이었다. CK-20에 대한 PCR 결과 각각 LD 11예종 l예(10%), ED 17예 중 1예(6%)에서 CK-20의 증폭이 관찰되었다. CK-20의 증폭이 관찰된 2예 중 ED 환자는 골수전이가 있었고, LD 환자는 진단당시는 원격전이가 없는 제한기의 환자였으나 후에 골전이가 관찰되었다. 결 론: 증폭이 관찰된 2 예의 환자가 모두 임상적으로는 골수 전이가 없는 상태에서 골전이가 발견됨으로써 CK-20의 발현이 혈행성 미세전이의 발견에 유용할 수 있을 가능성이 있을 것으로 추정할 수는 있으나, 골수전이가 확인되었던 7명중 6명에서는 CK-20이 발현되지 않아서, CK-20 보다 좀 더 유용한 표지자의 개발이 필요할 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4717-4721
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• 2013

Complete surgical resection of the primary tumour is a crucial predictive step for head and neck squamous cell carcinoma (HNSCC), because incomplete resection may lead to increase in the recurrence rate. Molecular cancer markers have been investigated as potential predictors of prognosis marker, to identify patients who are at high risk of local recurrence. This retrospective study aimed to determine the prognostic correlation between p53 and eIF4E expression and clinical characteristics, recurrence and overall survival. Forty eight HNSCC patients were selected between 2006 and 2009 diagnosed at the Royal Darwin Hospital, Darwin, Northern Territory, Australia. Out of 48, only those 24 with negative surgical margins with hematoxylin and eosin (HandE) were chosedn for further analysis. A total of 77 surgical margins were obtained and subsequently analysed by immunohistochemical (IHC) staining with monoclonal p53 and polyclonal eIF4E antibodies. Contingency table and ${\chi}^2$-test were used to investigate the correlation between p53 and eIF4E expression and clinical characteristics, recurrence and overall survival of the HNSCC patients. The follow up period was 74 months (range 1-74 months). The Kaplan-Meier method was used to generate recurrence and survival curves. This is a first retrospective study of Northern Territory patients, including Indigenous and non-Indigenous Australians. Molecular study of surgical margins could help to identify patients with and without clear margins after surgery and help in choice of the most appropriate adjuvant treatment for HNSCC patients.