• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년 추계학술대회논문집
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• pp.1-13
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• 2008

An efficient segregated algorithm for the coupling of velocity and pressure of incompressible fluid flow, called IDEAL (Inner Doubly-Iterative Efficient Algorithm for Linked-Equations), has been proposed by the present authors. In the algorithm there exist double inner iterative processes for pressure equation at each iteration level, which almost completely overcome two approximations in SIMPLE algorithm. Thus the coupling between velocity and pressure is fully guaranteed, greatly enhancing the convergence rate and stability of solution process. The performance of the IDEAL algorithm for three-dimensional incompressible fluid flow and heat transfer problems is analyzed and a systemic comparison is made between the algorithm and three other most widely-used algorithms (SIMPLER, SIMPLEC and PISO). It is found that the IDEAL algorithm is the most robust and the most efficient one among the four algorithms compared. This new algorithm is used for the velocity prediction of a new interface capturing method -VOSET, also proposed by the present author. It is found that the combination of VOSET and IDEAL can appreciably enhance both the interface capture accuracy and convergence rate of computations.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.3709-3713
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• 2015

Background: Many factors, including molecular ones, were demonstrated to be associated with long-term prognosis of hepatocellular carcinoma (HCC). Thus far, the expression and clinicopathologic and prognostic significance of the carboxyl terminus of Hsp70-interacting protein (CHIP) in B-type hepatitis virus (HBV)-related HCC remain unknown. Materials and Methods: CHIP expression was detected by immunohistochemical staining of surgical samples from 79 patients with HCC with HBsAg positivity. In addition, correlations with clinicopathologic parameters and patient survival were evaluated. Results: It was found that positive CHIP staining was observed in tumor, but not non-tumor, tissues. High expression of CHIP was significantly related to larger tumor size, with marginally significant associations noted for presence of portal vein invasion and higher serum a-fetoprotein level. In addition, univariate analysis showed that high CHIP expression was a powerful predictor for dismal overall and disease-free survival. However, independent prognostic implications of CHIP were not proven in multivariate Cox regression test. Conclusions: CHIP is overexpressed in HBV-related HCC and is associated with unfavorable biological behavior as well as poor prognosis. However, its prognostic role needs to be further validated.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6017-6022
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• 2012

Background: Resveratrol has been reported to have potential chemopreventive and apoptosis-inducing properties in a variety of tumor cell lines. Objective: In this study, to investigate the effects of resveratrol on protein kinase C (PKC) activity and apoptosis in human colon carcinoma cells, we used HT-29 cells and examined the $PKC{\alpha}$ and ERK1/2 signaling pathways. Methods: To test the effects of resveratrol on the growth of HT-29 cells, the cells were exposed to varying concentrations and assessed with the the MTT cell-viability assay. Fluorescence-activated cell sorter (FACS) analysis was applieded to determine the effects of resveratrol on cell apoptosis. Western blotting was performed to determine the protein levels of $PKC{\alpha}$ and ERK1/2. In inhibition experiments, HT-29 cells were treated with G$\ddot{o}$6976 or PD98059 for 30 min, followed by exposure to $200{\mu}M$ resveratrol for 72 h. Results: Resveratrol had a significant inhibitory effect on HT-29 cell growth. FACS revealed that resveratrol induced apoptosis. Western blotting showed that e phosphorylation of $PKC{\alpha}$ and ERK1/2 was significantly increased in response to resveratrol treatment. Pre-treatment with $PKC{\alpha}$ and ERK1/2 inhibitors (G$\ddot{o}$6976 and PD98059) promoted apoptosis. Conclusion: Resveratrol has significant anti-proliferative effects on the colon cancer cell line HT-29. The PKC-ERK1/2 signaling pathway can partially mediate resveratrol-induced apoptosis of HT-29 cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권4호
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• pp.1831-1835
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• 2014

Background: To investigate the relationship between extracellular matrix parameters and texture of prostatic lesions evaluated by transrectal real-time tissue elastography (TRTE). Methods: 120 patients suspicious for prostate cancer underwent TRTE. Targeted biopsies were carried out after 12-core systematic biopsy. Epithelia were stained with hematoxylin-eosin, and Victoria blue and Ponceau S were used to stain elastic-collagen fibers, and picric acid-sirius red for visualization of collagen type I (Col1) and III (Col3). Smooth muscles were visualized by immunohistochemistry. All image analyses were performed in a blind manner using Image Pro Plus 6.0, and the area ratios of epithelium, elastic fibers, collagen fibers and Col1/Col3 were determined. Results: 42 patients with typical elastograms were included in the final data analysis. Significant differences were detected between the benign and malignant groups in the area ratios of epithelium (P = 0.01), smooth muscles and Col1/Col3 (P = 0.04, P = 0.02, respectively). There were no significant differences in the area ratios of epithelium, smooth muscle and elastic fibers between the stiff and soft lesion groups. The area ratio of Col1 was ($0.05{\pm}0.03$) in the stiff group, and ($0.02{\pm}0.01$) in the soft group (P= 0.00). However, the area ratio of Col3 was ($0.03{\pm}0.02$) in the stiff group, and ($0.05{\pm}0.04$) in the soft group (P = 0.16). Col1/Col3 in the stiff group ($1.99{\pm}1.59$) was greater than in the soft group ($0.71{\pm}0.64$) (P = 0.01). Conclusions: Tissue hardness of prostatic tumors was mainly dependent on the Col1 content, Col1/Col3 being higher in malignant than in benign lesions, so the prostate tissue texture can be used as a target for distinguishing between the two with TRTE.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7769-7773
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• 2014

Background: Some tumor types are related to HIV, including non-Hodgkin lymphoma (NHL). The morbidity and mortality of NHL has remained high, even after highly active antiretroviral therapy (HAART) was introduced. We collected cases of AIDS with NHL, and evaluated the imaging features and strategies for diagnosis. Materials and Methods: There were 27 patients with AIDS and tumors confirmed by pathology. There were 9 patients with Burkitt lymphoma, 16 with diffuse large B cell lymphomas (DLBCLs), and 2 with primary central nervous system (PCNS) lymphomas. All of the patients underwent a series of imaging studies. Three radiologists analyzed the images, and any disagreement was discussed until consensus was reached. Results: The radiologic manifestations of AIDS with NHL were mainly masses and lymphadenopathy, 3 patients having one mass and 12 two or more masses. 7 patients had lymphadenopathy in one site and 3patients had lymphadenopathy in two or more sites. Coarse mucosal folds, thickening of the gastrointestinal wall, and lumen narrowing were typical manifestations of NHL within the gastrointestinal tract. There were 4 patients with masses and 5 with lymphadenopathy inthe 9 with Burkitt lymphoma, and 11 patients with masses 5 with lymphadenopathy in the 16 with DLBCLs. Conclusion: NHL is a malignancy that usually occurs in patients with AIDS. Imaging is an important method by which to evaluate lesions, masses, and lymphadenopathy. Fine needle aspiration biopsy and stereotaxis biopsy are useful methods by which to diagnose NHL.

• Asian Pacific Journal of Cancer Prevention
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• 제14권7호
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• pp.4089-4093
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• 2013

Objective: The rhabdomysarcoma (RMS) is most common soft tissue carcinoma in children, mostly found in the head and neck with high degree of malignancy. The current study aimed to summarize clinical data and evaluate treatment outcome of cases in a single hospital. Methods: Forty-one (24 male, 17 female) children with newly diagnosed RMS in Beijing Tong Ren Hospital were enrolled between November, 2004 and May, 2011. The. Students' t and Chi tests were then performed on retrospectively reviewed clinical data, followed by survival analysis based on the Kaplan Meier method using SPSS 17.0 software. Results: Of all cases, 32 were treated by common chemotherapy, and 3 cases with stage III RMS received high-dose chemotherapy and auto-peripheral blood stem cell transplantation (APBSCT). Side-effects in the former were: I grade for 62.5% (20/32), II grade for 28.1% (9/32), III grade account for 9.275% (3/32). Side-effects of 3 cases with APBSCT: 2 were I grade, 1 was III grade. The median follow-up time of 41 RMS cases was 41 months. Four cases were lost to follow-up, 7 cases recurred, and 5 cases died of cerebral metastasis, witha total survival rate was 86.5% (32/37). CR rate was 67.6% (25/37), PR was 18.9% (7/37). Conclusion: Multidiscipline treatment including chemotherapy, radiotherapy, surgery and auto-PBSCT is highly recommended for pediatric patients with head and neck RMS.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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• pp.5395-5399
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• 2014

Purpose: This study was designed to evaluate the outcomes of laparoscopic colorectal resection in a period of learning curve completed by surgeons with different experience and aptitudes with a view to making clear whether seniors had a better learning curve compared with juniors. Methods: From May 2010 to August 2012, the first twenty patients underwent laparoscopic colorectal resection completed by each surgeon were selected for analysis retrospectively. A total of 240 patients treated by 5 seniors and 7 juniors were divided into the senior group (n=100) and the junior group (n=140). The short-term outcomes of laparoscopic surgery of the two groups were compared. Results: The mean numbers of lymph nodes harvested were $21.2{\pm}11.0$ in the senior group and $17.3{\pm}11.5$ in the junior group (p=0.010); The mean operative times were $187.9{\pm}60.0min$ as compared to $231.3{\pm}55.7min$ (p=0.006), and blood loss values were $177.0{\pm}100.7ml$ and $234.0{\pm}185ml$, respectively (p=0.001); Conversion rate in the senior group was obviously lower than in the junior group (10.0% vs 20.7%, p=0.027) and the mean time to passing of first flatus were $3.3{\pm}0.9$ and $3.8{\pm}0.9$ days (p=0.001). For low rectal cancer, the sphincter preserving rates were 68.7% and 35.3% (p=0.027). Conclusions: Seniors could perform laparoscopic colorectal resection with relatively better oncological outcomes and quicker recovery, and seniors could master the laparoscopic skill more easily and quickly. Seniors had a better learning curve for laparoscopic colorectal cancer resection compared to juniors.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4853-4858
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• 2013

Objectives: To investigate whether hypoxia has an effect on regulation of multidrug resistance (MDR) to chemotherapeutic drugs in laryngeal carcinoma cells and explore the role of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$). Methods: Laryngeal cancer cells were cultured under normoxic and hypoxic conditions. The sensitivity of the cells to multiple drugs and levels of apoptosis induced by paclitaxel were determined by MTT assay and annexin-V/propidium iodide staining analysis, respectively. HIF-$1{\alpha}$ expression was blocked by RNA interference. The expression of HIF-$1{\alpha}$ gene was detected by real-time quantitative RT-PCR and Western blotting. The value of fluorescence intensity of intracellular adriamycin accumulation and retention in cells was evaluated by flow cytometry. Results: The sensitivity to multiple chemotherapy agents and induction of apoptosis by paclitaxel could be reduced by hypoxia (P<0.05). A the same time, the adriamycin releasing index of cells was increased (P<0.05). However, resistance acquisition subject to hypoxia in vitro was suppressed by down-regulating HIF-$1{\alpha}$ expression. Conclusion: HIF-$1{\alpha}$ could be considered as a key regulator for mediating hypoxia-induced MDR in laryngeal cancer cells via inhibition of drug-induced apoptosis and decrease in intracellular drug accumulation.

• Asian Pacific Journal of Cancer Prevention
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• 제17권12호
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• pp.5087-5094
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• 2016

mTOR, the mammalian target of rapamycin, is a conserved serine/threonine kinase which belongs to the phosphatidyl-linositol kinase-related kinase (PIKK) family. It has two complexes called mTORC1 and mTORC2. It is well established that mTOR plays important roles in cell growth, proliferation and differentiation. Over-activation of the mTOR pathway is considered to have a relationship with the development of many types of diseases, including polycystic ovary syndrome (PCOS) and ovarian cancer (OC). mTOR pathway inhibitors, such as rapamycin and its derivatives, can directly or indirectly treat or relieve the symptoms of patients suffering from PCOS or OC. Moreover, mTOR inhibitors in combination with other chemical-molecular agents may have extraordinary efficacy. This paper will discuss links between mTOR signaling and PCOS and OC, and explore the mechanisms of mTOR inhibitors in treating these two diseases, with conclusions regarding the most effective therapeutic approaches.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2133-2137
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• 2012

Objective: To investigate the prognostic role of antigen KI-67 (Ki-67) and G1/S-specific cyclin-D1 (cyclin-D1) in patients with laryngeal squamous cell carcinoma (LSCC). Methods: Immunohistochemical staining (IHS) was used to determine the protein expression of Ki-67 and cyclin-D1 in LSCC tissues. Kaplan-Meier survival curves was calculated with reference to Ki-67 and cyclin-D1 levels. Results: Cyclin-D1 and Ki67 were expressed in the nuclei of cancer cells. Among the total of 92 cancer tissues examined by immunohistochemistry, 60 (65.22%) had cyclin-D1 overexpression and 56 (60.87%) had Ki67 overexpression. Cyclin-D1 overexpression is associated with the advanced stage of the cancer (P=0.029), but not with gender, age, stage of cancer, histological differentiation, anatomical site, smoking history and alcohol consumption history. Ki67 overexpression is not associated with the advanced stage, gender, age, histological differentiation, anatomical site, smoking history and alcohol consumption history. A statistically significant correlation was found between lymph node status and the expression of Ki67 (p = 0.025). Overexpression of cyclin-D1 was correlated to shorter relapse-free survival period (P<0.001). Conclusions: Overexpression of cyclin-D1 can be used as a marker to predict relapse in patients with LSCC after primary curative resection.