• Journal of Life Science
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• v.32 no.2
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• pp.167-174
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• 2022

In modern society, interest in antioxidants is increasing as the stress caused by oxidants increases. However, the demand for synthetic antioxidants is decreasing because some studies have confirmed that they are harmful when consumed in large quantities; thus, studies on antioxidants derived from natural substances are actively being conducted to replace synthetic antioxidants. Blueberry, known as one of the world's top ten long-lived foods, is a plant of the Vaccinium (Ericaceae) family, and various pharmacological activities of blueberry including antioxidant activity have been studied. Vaccinium oldhamii (VO) is a deciduous broad-leaved shrub in the same genus as blueberries, and in this paper, we summarize the studies on the efficacy analysis of VO extracts and purified products. The content of phenolic compounds in VO fruits was proportional to antioxidant and anti-influenza activity such as the inhibition of NO production, and the total content of polyphenols and anthocyanin was higher than that in blueberries. VO fruit extracts showed anti-inflammatory activity and anti-cancer activity against human acute leukemia; in contrast, VO branch extracts showed anti-inflammatory activity, activity to inhibit osteoclast differentiation and bone resorption due to inflammatory response, and anti-cancer activity against several human cancer cell lines. Compared to blueberries, VO showed higher phenolic compound content, antioxidant activity, and various physiological activities. In addition, VO is considered to have sufficient value as an alternative crop to blueberries, such as it can be grown natively in Korea, with simple mass cultivation and no need to pay royalties for commercialization.

• Journal of Life Science
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• v.34 no.6
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• pp.418-425
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• 2024

Solid tumors are heterogeneous populations of multiple cell types. While the majority of the cells that comprise cancer are unable to divide, cancer stem cells have self-renewal and differentiation properties. Normal stem cell pathways that control self-renewal are overactivated in cancer stem cells, making cancer stem cells important for cancer cell expansion and progression. Dick first proposed the definition of cancer stem cells in acute myeloid leukemia, according to which cancer stem cells can be classified based on the expression of cell surface markers. Cancer stem cells maintain their potential in the tumor microenvironment. Multiple cell types in the tumor microenvironment maintain quiescent cancer stem cells and serve as regulators of cancer growth. Since current cancer treatments target proliferative cells, quiescent state cancer stem cells that are resistant to treatment increase the risk of recurrence or metastasis. Various signals of the tumor microenvironment induce changes to become a tumor-supportive environment by remodeling the vasculature and extracellular matrix. To effectively treat cancer, cancer stem cells and the tumor microenvironment must be targeted. Therefore, it is important to understand how the tumor microenvironment induces reprogramming of the immune response to promote cancer growth, immune resistance, and metastasis. In this review, we discuss the cellular and molecular mechanisms that can enhance immunosuppression in the tumor microenvironment.

• Clinical and Experimental Pediatrics
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• v.45 no.3
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• pp.370-375
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• 2002

Purpose : In most cases, myelodysplastic syndrome(MDS) transforms into a more aggressive state or acute myelogenous leukemia; it's prognosis is very poor. It is believed that hematopoietic stem cell transplantation(HSCT) is the only curative treatment of MDS, but available data in children are very sparse. In this report, the short term outcome of HSCT in childhood MDS was analyzed. Methods : Ten children with MDS(CMMoL 5, RAEB 3, RAEBt 2) underwent HSCT(HLA-matched sibling transplantation 4, HLA-matched unrelated transplantation 4, cord blood transplantation 1, HLA-mismatched familial transplantation 1) between November 1995 and January 2001 at St. Mary's Hospital. Median follow-up duration was 11 months. Results : Engraftment was successful in all cases and 8 patients are alive without disease. Three cases of VOD were observed and improved without complication. Four cases of grade II and 1 case of grade III acute GVHD were observed and well controlled with treatment. Three patients relapsed after transplantation. One patient is alive without disease after cytoreduction with allogenic stem cell rescue and 2 patients died of relapse. Conclusion : HSCT is a curative strategy of MDS and the survival rate is relatively higher than that of adults. But there is an obvious need for more studies because of the small number of patients and the short duration of the follow-up.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.133-140
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• 1994

Recently, there are many considerations and studies on biological effects of radiations in radiation workers, as well as in accidentally or therapeutically irradiated persons. The most practical and reliable method of dosimetry for radiation accidents is the scoring of gross chromosomal aberrations in human lymphocytes (Ydr) as a biological dosimetry. By the way, although usual doses of $^{131}I$ administered therapeutically for thyroid cancer are ranging from 100 mCi to 200 mCi, there are differences of absorbed doses and Ydr, ranging from 0.004 to 0.04, on equally administered $^{131}I$ due to variations in metabolic characteristics, stage of tumors and physical status of subjects. In this study, We exert to obtain the dose-response relationships of $^{131}I$, as a good guide to evaluating acute effects of accidental irradiations and radiation induced leukemia or solid tumor, by in vitro induction of chromosomal aberrations. we studied the relationship between radiation dose (D) and the frequency of chromosomal aberrations (Ydr) obserbed in peripheral lymphocytes that were irradiated in vitro with $^{131}I$ at doses ranging from 0.05 to 6.00 Gy. By scoring cells with unstable chromosomal aberrations (dicentric chromosomes and ring chromosomes) we obtained this linear-quadratic dose response equation Ydr=0.064351 $D^2$-0.13143 D+0.045684 This dose-response relationship may be useful for evaluating acute and chronic $^{131}I$ induced biological effects.

• Journal of Veterinary Clinics
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• v.24 no.4
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• pp.479-485
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• 2007

A retrospective study of 94 hypercalcemic dogs was performed to find out most common causes that lead to hypercalcemia through investigating dogs referred to the Veterinary Teaching Hospital of Konkuk University from 2002 to 2004. During the study period, hypercalcemia was found in 94 dogs of 19 breeds, and they were evaluated as case group. Control group was made up of 94 dogs of 18 breeds without hypercalcemia admitted for the same study period. For general signalments, there were no significant differences between case and control group with the exception of age distribution. Shih-tzu(17.02%) and Yorkshire terrier(26.60%) was the most common breed in case and control group, respectively. The most common diseases associated with hypercalcemia were chronic renal failure (18.09%), acute renal failure(14.89%), and renal calculi(6.38%). Malignant neoplasia(lymphoma, hemangiosarcoma, chronic lymphocytic leukemia, mammary gland tumor, and multiple myeloma) and endocrinopathies(hyperadrenocorticism, hyperthyroidism, hypoadrenocorticism, and hypothyroidism) occupied 8.5% and 6.4%, respectively. This report is a first retrospective study of hypercalcemic dogs in South Korea.

• Radiation Oncology Journal
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• v.21 no.3
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• pp.192-198
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• 2003

Purpose: Current results of autologous stem cell transplantation (SCT) suggest that this procedure may prolong disease free survival In patients with acute myeloid leukemia (AML). Autologous SCT is increasingly used as treatment for AML in first remission. The aim of this study was to evaluate the outcome of autologous SCT for patients with AML in first remission treated by autologous SCT using cytarabine, melphalan and total body irradiation (TBI) as the conditioning regimen. Materials and Methods: Between January 1995 and December 1999, 29 patients with AML in first remission underwent autologous SCT. The median age of patients was 33 years (range, 16 to 47). The conditioning regimen consisted of cytarabine ($3.0\;gm/m^2$ for 3 days), melphalan ($100\;gm/m^2$ for 1 day) and TBI (total 1000 cGy in five fractions over 3 days). Results: The median follow up was 40 months with a range of 3 to 58 months. The 4-year cumulative probability of disease free survival was 69.0%, and median survival was 41.5 months. The 4-year relapse rate was 27.6%. The factor Influencing disease free survival and relapse rate was the French-American-British (FAB) classification ($M_3$ group vs. other groups; p=0.048, p=0.043). One patient died from treatment-related toxicity. Conclusion:: Although the small number of patients does not allow us to draw any firm conclusion, our results were encouraging and suggest that the association of cytarabine, melphalan and TBI as a conditioning regimen for autologous SCT for AML on first remission appears to be safe and effective.

• KSBB Journal
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• v.22 no.1
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• pp.22-29
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• 2007

The water-soluble materials extracted from fruit bodies and mycelium of H. erinaceum were prepared. In-vitro anticancer activities on cancer cells and In-vivo proliferation effect on mouse peritoneal exudate cell and spleen cell of samples were investigated. Also, nitric oxide (NO) generation of peritoneal exudate cell, IL-2 production capacity of spleen cells and phagocytic activity of peritoneal macrophages were examined. The water extracts of H. erinaceum suppressed the proliferation of cancer cell (HeLa, Raw264.7, Jurkat, KATO3, EL4, LyD9) with concentration-dependent. The water extract from fruit body showed better suppression effect than that from mycelium in most of cancer cells used. The anticancer effect of water extract of fruits body in the range of 0.01 and 10 mg/ml for Raw 264.7 and EL4 cell lines were the same as the Taxol with one thousandth equivalent of fruit body concentration. Water extracts of fruit body and liquid-cultured products of H. erinaceum induced nitric oxide (NO) generation of peritoneal exudate cell and increased NO generation by stimulus of lipopolysaccharide. Water extracts alone did not induce the proliferation and IL-2 production capacity of spleen cells. However, spleen's proliferation and IL-2 production were induced significantly by the addition of lipopolysaccharide and Con A (concanavalin A) or Con A alone, and the effectiveness of mycelium extract with water were more active than those from fruit body.

• Journal of Life Science
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• v.26 no.3
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• pp.376-386
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• 2016

Apoptosis induction has been proposed as an efficient mechanism by which malignant tumor cells can be removed following chemotherapy. The intrinsic mitochondria-dependent apoptotic pathway is frequently implicated in chemotherapy-induced tumor cell apoptosis. Since DNA-damaging agent (DDA)-induced apoptosis is mainly regulated by the tumor suppressor protein p53, and since more than half of clinical cancers possess inactive p53 mutants, microtubule-damaging agents (MDAs), of which apoptotic effect is mainly exerted via p53-independent routes, can be promising choice for cancer chemotherapy. Recently, we found that the apoptotic signaling pathway induced by MDAs (nocodazole, 17α-estradiol, or 2-methoxyestradiol) commonly proceeded through mitotic spindle defect-mediated prometaphase arrest, prolonged Cdk1 activation, and subsequent phosphorylation of Bcl-2, Mcl-1, and Bim in human acute leukemia Jurkat T cells. These microtubule damage-mediated alterations could render the cellular context susceptible to the onset of mitochondria-dependent apoptosis by triggering Bak activation, Δψm loss, and resultant caspase cascade activation. In contrast, when the MDA-induced Bak activation was inhibited by overexpression of anti-apoptotic Bcl-2 family proteins (Bcl-2 or Bcl-xL), the cells in prometaphase arrest failed to induce apoptosis, and instead underwent mitotic slippage and endoreduplication cycle, leading to formation of populations with 8N and 16N DNA content. These data indicate that cellular apoptogenic mechanism is critical for preventing polyploid formation following MDA treatment. Since the formation of polyploid cells, which are genetically unstable, may cause acquisition of therapy resistance and disease relapse, there is a growing interest in developing new combination chemotherapies to prevent polyploidization in tumors after MDA treatment.

• Clinical and Experimental Pediatrics
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• v.46 no.6
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• pp.566-571
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• 2003

Purpose : Leukoencephalopathy(LE) is one of the most serious complications in children with hematologic malignancies during the course of treatment. Early recognition is important to reduce the impact and sequelae from LE. We therefore investigated the clinical features of LE following central nervous system(CNS) prophylaxis in children with hematologic malignancies and evaluated the significance of regular check-ups of brain MRI. Methods : We retrospectively reviewed children with hematologic malignancies who had CNS prophylaxis including intrathecal(IT) methotrexate(MTX) and/or cranial irradiation at the Department of Pediatrics, Kyungpook National University Hospital from Oct. 1995 to May 2002. Fifteen cases of acute leukemia and one case of lymphoma who experienced LE following CNS prophylaxis were included in the study. Clinical data were analyzed from the medical records and brain MRIs were reviewed by neuroradiologists. Results : The ages ranged from 1 to 13 years(median age=5.2 years), and the male to female ratio was 3 : 1. The time interval from the beginning of chemotherapy to the time of diagnosis of LE ranged from 2 to 17 months. They all had IT MTX two to 15 times and ten underwent cranial irradiation(1,800 rads). At the time of diagnosis, ten of them had neuropsychiatric symptoms including seizures, personality changes, headache, etc. After the change of treatment modality, four cases showed significant improvement on follow-up MRIs, six cases had no significant changes and two had worsening of LE. Four patients died of infection and bone marrow relapse. Conclusion : CNS prophylaxis with IT therapy and cranial irradiation may cause leukoencephalopathy during the course of treatment. As a result, regular brain MRI check-up is recommended for the early detection and reducing the incidence of LE, along with changes in the treatment modality.

• Tuberculosis and Respiratory Diseases
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• v.59 no.1
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• pp.30-38
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• 2005

Background : Arsenic trioxide ($As_2O_3$) has been used to treat acute promyelocytic leukemia, and it induces apoptosis in a variety of solid tumor cell lines including non-small cell lung cancer cells. However, nonsteroidal antiinflammatory drugs (NSAID) can enhance tumor response to chemotherapeutic drugs or radiation. It was previously demonstrated that a combination treatment with $As_2O_3$ and sulindac induces the apoptosis of NCI-H157 human lung carcinoma cells by activating the caspase cascade. This study aimed to determine if a combination treatment augmented its apoptotic potential through other pathways except for the activation of the caspase cascade. Material and Methods : The NCI-H157 cells were treated with $As_2O_3$, sulindac and antioxidants such as glutathione (GSH) and N-acetylcysteine (NAC). The cell viability was measured by a MTT assay, and the level of intracellular hydrogen peroxide ($H_2O_2$) generation was monitored fluorimetrically using a scopoletin-horse radish peroxidase (HRP) assay. Western blotting and mitochondrial membrane potential transition analysis were performed in order to define the mechanical basis of apoptosis. Results : The viability of the cells was decreased by a combination treatment of $As_2O_3$ and sulindac, and the cells were protected using antioxidants in a dose-dependent manner. The increased $H_2O_2$ generation by the combination treatment was inhibited by antioxidants. The combination treatment induced changes in the mitochondrial transmembrane potential as well as the expression of the Bcl-2 family proteins, and increased cytochrome c release into the cytosol. However, the antioxidants inhibited the effects of the combination treatment. Conclusion : Combination treatment with $As_2O_3$ and sulindac induces apoptosis in NCI-H157 human lung carcinoma cells via ROS generation with a mitochondrial dysfunction.