• 한국환경성돌연변이발암원학회지
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• 제22권4호
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• pp.266-273
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• 2002

The dose dependence of the severity of radiation-induced thymic lymphoma in C57BL/6J mice was studied. Mice were exposed to fractionated irradiation at the total doses of 4.0, 6.0 and 8.0 Gy (four irradiations at 8-day intervals) starting from 33 days after birth. Pathological and histological changes of each mouse were observed after periodical sacrifice at day 75, 100, 125, 150, 175, 200, 250, 300 after the first irradiation. The severity of cancers were classified into 4 stages by clinical signs with respect to the enlargement of the thymus, spleen, liver, the progression of the cancer in the thymus, and the metastasis to the spleen, liver, lung and the lymphatic nodes. Among the 490 mice observed, 146 mice had thymic lymphoma. A clear dose-effect relationship was observed as well as the dose-response relationship. Also, periodical observation showed that thymic lymphoma was first induced in mice sacrificed at day 100 (130days old), and metastasize in the order of spleen, lung, liver and then the lymphatic nodes. The results suggest that radiation may be involved not only as a tumor initiator but also as a tumor promoter, and a tumor progression-enhancing agent.

• 대한세포병리학회지
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• 제2권1호
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• pp.36-42
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• 1991

We report 4 cases of malignant thymoma which were composed of 2 cases of invasive thymoma and 2 cases of thymic carcinoma. The cytologic findings of invasive thymoma were similar to those of benign thymoma. The distinctive cytologic features of thymic carcinoma were necrotic background, irregular clusters and individually scattered arrangement of anaplastic epithelial cells, and some scattered mature small lymphocytes. These findings may be found in the Hodgkin's lymphoma, seminoma, and metastatic squamous ceil carcinoma, undifferentiated carcinoma, and large ceil carcinoma of the lung. But, the feature of irregular clustering of anaplastic epithelial cell haying scanty cytoplasm was different from Hodgkin's lymphoma and seminoma. Clinical and radiologic findings as well as cytologic finding were helpful in differential diagnosis of thymic carcinoma from metastatic carcinoma.

• Journal of Yeungnam Medical Science
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• 제27권2호
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• pp.98-104
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• 2010

원발성 전 종격동 종양은 종격동 종양의 반이상을 차지하고 그 종류도 다양하다. 흉선 상피 종양이 가장 흔하고 악성 흉선종은 드물다. 생식세포종은 두 번째로 흔한 전 종격동 종양으로 보다 어린나이에 발생하며 대부분 양성이다. 임파종은 대부분 전신성 질환의 흉부 침습 형태로 나타나나 원발성 흉부 임파종은 Hodgkin씨 병이 많다. 저자는 대표적인 전종격동 종양의 임상증상과 영상의학적 소견을 소개한다.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2010년도 춘계 학술발표회 및 심포지엄
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• pp.48-51
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• 2010

• 환경생물
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• 제22권4호
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• pp.507-512
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• 2004

This study was focused on the risk assessment of whether radiofrequency electromagnetic fields generated by mobile phone is cytogenetically toxic or not. We conducted the effects of 835-MHz electromagnetic field (EMF) on DNA strand breaks in mouse thymic lymphoma L5178Y $Tk^{+/1-}$ cells using alkaline comet assay. EMF frequency 835-MHz we chosen is one of the most popular communication frequency bands in Korean code-division multiple-access (CDMA) mobile phone system. The cells were exposed to 835-MHz EMF alone or 835-MHz EMF combined with cyclophosamide(CPA) or 4-nitroquinoline-1-oxide (4NQO) at specific absorption rate (SAR) of 4.0 W $kg^{-l}$ for 24 and 48hrs. DNA damage expressed as tail moment was increased more than two-fold after exposure to 835-MHz EMF for 24 and 48hr. In particular, CPA for 48hr and 4NQO for 24 hr enhanced notably the tail moment to 9-fold and 16-fold in the presence of 835-MHz EMF, respectively, compared to each single treatment. From these results, it appears that exposure to CDMA-mobile phone radiation at 835-MHz frequency may potentiate DNA strand breaks of mouse thymic lymphoma L5178Y $Tk^{+/1-}$;cells under the defined conditions of this study.

• IMMUNE NETWORK
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• 제2권4호
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• pp.217-222
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• 2002

Background: Scid.adh is a recently developed murine thymic lymphoma cell line, which has been used as in vitro model for the study of double negative stage III thymocytes. In this study, we compared the expression profile of a number of genes and proteins, which are tightly related to T cell development and apoptosis, in thymic lymphoma cell lines, R1.1, EL-4, and Scid.adh for the developmental staging. Methods: We examined the expression of development marker genes and proteins in three lymphoma cell lines by flow cytometry and RT-PCR. In addition, the expression of apoptosis-related molecules including bcl-2, bax and Fas was also investigated. Results: As previously reported, Scid.adh cell line expressed CD8 and CD25 but not TCR ${\alpha}$ chain, while R1.1 cells expressed TCR ${\alpha}$ chain and both CD4 and CD8 transcripts. These suggest that R1.1 might be in double positive stage, and low level of CD44 expression and the absence of CD25 support this suggestion. In contrast, EL-4 cells showed high level of TCR ${\alpha}$ chain transcript, and low-level of CD4 expression, suggesting that EL-4 is in more mature stage than R1.1. Further, this suggestion was supported by the lack of mT-20 in EL-4 cells, which is expressed in the immature thymocytes, and Scid.adh and R1.1 cell lines, but not in the terminally differentiated thymocytes and peripheral T cells. Among the apoptosis-related gene, transcripts of bcl-2 gene were detected in both R1.1 and EL-4 but not in Scid.adh cells, while bax was expressed in all cell lines. Fas expression was the highest in EL-4 cells and low in Scid.adh cell line. Conclusion: R1.1 cell may represent double positive stage, and EL-4 is more differentiated cell line. In addition, Scid.adh and EL-4 cell lines are suspected to be useful for the study of function of bcl-2 family and Fas during the thymocyte development, respectively.

• 대한수의학회지
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• 제27권2호
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• pp.269-275
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• 1987

Radiation-induced life shortening, carcinogenesis and other pathological changes were investigated in NIH(GP) mice after $^{60}Co-{\gamma}$ ray irradiation(100~700rads). The results were summarized as follows: 1. There were little difference in body weights, hematological examination and other clinical findings between normal and irradiated groups. 2. Mean survival time of the mice after irradiation were decreased dose-dependently. 3. Main gross findings of the mice irradiated were appeared as enlargement of spleen, thymus and lymph nodes, tumorous nodules of lung and cyst of ovary. Especially, enlargement of thymus was promineort in high dose group. 4. Microscopically, there were various findings including myeloid leukemia, thymic lymphoma, lung adenoma, adenosquamous cell carcinoma of pancreas, pneumonia and other pathological changes. Especially thymic lymphoma was highly frequent in the 700 rads group.

• Molecules and Cells
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• 제38권3호
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• pp.251-258
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• 2015

Germline mutations in the breast cancer type 2 susceptibility gene (BRCA2) are linked to familial breast cancer and the progressive bone marrow failure syndrome Fanconi anaemia. Established Brca2 mouse knockout models show embryonic lethality, but those with a truncating mutation at the C-terminus survive to birth and develop thymic lymphoma at an early age. To overcome early lethality and investigate the function of BRCA2, we used T cell-specific conditional Brca2 knockout mice, which were previously shown to develop thymic lymphoma at a low penetrance. In the current study we showed that the number of peripheral T cells, particularly na$\ddot{i}$ve pools, drastically declined with age. This decline was primarily ascribed to improper peripheral maintenance. Furthermore, heterozygous mice with one wild-type Brca2 allele manifested reduced T cell numbers, suggesting that Brca2 haploinsufficiency might also result in T cell loss. Our study reveals molecular events occurring in Brca2-deficient T cells and suggests that both heterozygous and homozygous Brca2 mutation may lead to dysfunction in T cell populations.

• Korean Journal of Radiology
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• 제22권1호
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• pp.139-154
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• 2021

Magnetic resonance imaging (MRI) has become a crucial tool for evaluating mediastinal masses considering that several lesions that appear indeterminate on computed tomography and radiography can be differentiated on MRI. Using a three-compartment model to localize the mass and employing a basic knowledge of MRI, radiologists can easily diagnose mediastinal masses. Here, we review the use of MRI in evaluating mediastinal masses and present the images of various mediastinal masses categorized using the International Thymic Malignancy Interest Group's three-compartment classification system. These masses include thymic hyperplasia, thymic cyst, pericardial cyst, thymoma, mediastinal hemangioma, lymphoma, mature teratoma, bronchogenic cyst, esophageal duplication cyst, mediastinal thyroid carcinoma originating from ectopic thyroid tissue, mediastinal liposarcoma, mediastinal pancreatic pseudocyst, neurogenic tumor, meningocele, and plasmacytoma.

• Journal of Life Science
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• 제12권1호
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• pp.22-26
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• 2002

CS21 lymphoma cells that preferentially metastasize to lymph nodes after s.c. inoculation into BALB/c mice were grown in vitro in the presence of CA12 stromal cells isolated from lymph nodes. To obtain fundamental data on identification and characterization of the soluble factor(s) produced by CA12 stromal cells, we investigated the biological profile of the conditioned medium produced by CAl2 stromal cells. CAl2 conditioned medium has no affinity with Con A. CAl2 conditioned medium is associated with the proliferation of splenic T- and thymic T-cells with-out adding mitogen, although the conditioned medium cannot induce the differentiation of thymocytes. Additionally, we showed that H-7, not HA-1004 inhibits CS21 cell proliferation. These results suggest that CAl2 conditioned medium has a specific soluble factor(s) produced by lymph node stromal cells.