690 research outputs found
BIOMECHANICAL TRAITS ANALYSIS WHEN PERFORMING OF JUDO UCHIMATA BY POSTURE AND VOLUNTARY RESISTANCE LEVELS OF UKE
The purpose of this study was to analyze the biomechanical traits variables when performing uchimata (inner thigh reaping throw) by voluntary resistance levels (VRL) and two postures of uke (defender, receiver) in Judo. The postures of uke were shizenhontai (straight natural posture:NP) and jigohontai (straight defensive posture:DP), VRL of uke were 0% and 100%, respectively. The biomechanical variables were temporal (total time-required: TR), postures and COG during performing uchimata. It's important for jUdoists to prepare for individual analysis. prescription and countermeasures because they have experienced several variables when performing techniques according to opponent's postures and VRL in biomechanical aspects
5-aminolevulinic acid-incorporated poly(vinyl alcohol) nanofiber-coated metal stent for application in photodynamic therapy
Poly(L-histidine)-tagged 5-aminolevulinic acid prodrugs: new photosensitizing precursors of protoporphyrin IX for photodynamic colon cancer therapy
Renjith P Johnson,1* Chung-Wook Chung,2* Young-Il Jeong,2 Dae Hwan Kang,2 Hongsuk Suh,3 Il Kim,11WCU Centre for Synthetic Polymer Bioconjugate Hybrid Materials, Department of Polymer Science and Engineering, Pusan National University, Pusan, 2National Research and Development Center for Hepatobiliary Cancer, Pusan National University, Yangsan Hospital, Yangsan, Gyeongnam, 3Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Pusan, Korea*These authors contributed equally to this workBackground: 5-Aminolevulinic acid (ALA) and its derivatives have been widely used in photodynamic therapy. The main drawback associated with ALA-based photodynamic therapy (ALA-PDT) and ALA fluorescence diagnosis results from the hydrophilic nature of ALA and lack of selectivity for tumor versus nontumor cells. The application of certain triggers, such as pH, into conventional sensitizers for controllable 1O2 release is a promising strategy for tumor-targeted treatment.Methods: A series of pH-sensitive ALA-poly(L-histidine) [p(L-His)n] prodrugs were synthesized via ring opening polymerization of 1-benzyl-N-carboxy-L-histidine anhydride initiated by the amine hydrochloride group of ALA itself. As an alternative to ALA for PDT, the synthesized prodrugs were used to treat a cultured human colon cancer HCT116 cell line under different pH conditions. The effect of ALA-p(L-His)n derivatives was evaluated by monitoring the fluorescence intensity of protoporphyrin IX, and measuring the cell survival rate after suitable light irradiation.Results: The cytotoxicity and dark toxicity of ALA and synthesized ALA-p(L-His) derivatives in HEK293T and HCT116 cells in the absence of light at pH 7.4 and 6.8 shows that the cell viability was relatively higher than 100%. ALA-p(L-His)n showed high phototoxicity and selectivity in different pH conditions compared with ALA alone. Because the length of the histidine chain increases in the ALA-p(L-His)n prodrugs, the PDT effect was found to be more powerful. In particular, high phototoxicity was observed when the cells were treated with ALA-p(L-His)15, compared with treatment using ALA alone.Conclusion: The newly synthesized ALA-p(L-His)n derivatives are an effective alternative to ALA for enhancing protoporphyrin IX production and the selectivity of the phototoxic effect in tumor cells.Keywords: 5-aminolevulinic acid, photodynamic therapy, poly(L-histidine), bioconjugate, cancer cell
Transcatheter Arterial Chemoembolization of Hepatocellular Carcinoma: Prevalence and Causative Factors of Extrahepatic Collateral Arteries in 479 Patients
OBJECTIVE: We wanted to investigate the prevalence and causative factors of extrahepatic arterial blood supply to hepatocellular carcinoma (HCC) at its initial presentation and during chemoembolization. MATERIALS AND METHODS: Between February 1998 and April 2000, consecutive 479 patients with newly diagnosed HCC were prospectively enrolled into this study. A total of 1629 sessions of transcatheter arterial chemoembolization (TACE) were performed in these patients (range: 1-15 sessions; mean: 3.4 sessions) until April 2004. For each TACE procedure, we determined the potential extrahepatic collateral arteries (ExCAs) depending on the location of the tumor, and we performed selective angiography of all suspected collaterals that could supply the tumor. The prevalence of ExCAs and the causative factors were analyzed. RESULTS: At initial presentation, 82 (17%) of these 479 patients showed 108 ExCAs supplying tumors. Univariate analysis showed that tumor size (p or =5 cm) was significantly higher than that for those patients with a small tumor (< 5 cm) (p < 0.01). CONCLUSION: The presence of ExCAs supplying HCC is rather common, and the tumor size is a significant causative factor for the development of these collateral arteries.This study was supported by a grant
(0620220-1) from the National R & D
Program for Cancer Control, Ministry of
Health & Welfare, Republic of Korea
Effect of 5-aminolevulinic acid-based photodynamic therapy via reactive oxygen species in human cholangiocarcinoma cells
Cancer cells have been reported to exhibit an enhanced capacity for protoporphyrin IX (PpIX) synthesis facilitated by the administration of 5-aminolevulinic acid (ALA). We investigated the effect of ALA-based photodynamic therapy (PDT) on human cholangiocarcinoma cells (HuCC-T1). Since protoporphyrin IX (PpIX), a metabolite of ALA, can produce reactive oxygen species (ROS) under irradiation and then induce phototoxicity, ALA-based PDT is a promising candidate for the treatment of cholangiocarcinoma. When various concentrations of ALA (0.05β2 mM) were used to treat HuCC-T1 cells for 6 or 24 hours, the intracellular PpIX level increased according to the ALA concentration and treatment time. Furthermore, an increased amount of PpIX in HuCC-T1 cells induced increased production of ROS by irradiation, resulting in increased phototoxicity
Doxorubicin-incorporated polymeric micelles composed of dextran-b-poly(DL-lactide-co-glycolide) copolymer
Young-Il Jeong1,*, Do Hyung Kim1,2,*, Chung-Wook Chung1, Jin-Ju Yoo1, Kyung Ha Choi1, Cy Hyun Kim1,2, Seung Hee Ha1, Dae Hwan Kang1,2 1National Research and Development Center for Hepatobiliary Cancer, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea, Research Institute for Convergence of Biomedical Science and Technology, 2School of Medicine, Pusan National University, Yangsan, Republic of Korea*These authors contributed equally to this work.Background: Polymeric micelles using amphiphilic macromolecules are promising vehicles for antitumor targeting. In this study, we prepared anticancer agent-incorporated polymeric micelles using novel block copolymer.Methods: We synthesized a block copolymer composed of dextran and poly (DL-lactide-co-glycolide) (DexbLG) for antitumor drug delivery. Doxorubicin was selected as the anticancer drug, and was incorporated into polymeric micelles by dialysis. Polymeric micelles were observed by transmission electron microscopy to be spherical and smaller than 100 nm, with a narrow size distribution. The particle size of doxorubicin-incorporated polymeric micelles increased with increasing drug content. Higher initial drug feeding also increased the drug content. Results: During the drug-release study, an initial burst release of doxorubicin was observed for 10 hours, and doxorubicin was continuously released over 4 days. To investigate the in vitro anticancer effects of the polymeric micelles, doxorubicin-resistant HuCC-T1 cells were treated with a very high concentration of doxorubicin. In an antiproliferation study, the polymeric micelles showed higher cytotoxicity to doxorubicin-resistant HuCC-T1 cells than free doxorubicin, indicating that the polymeric micelles were effectively engulfed by tumor cells, while free doxorubicin hardly penetrated the tumor cell membrane. On confocal laser scanning microscopy, free doxorubicin expressed very weak fluorescence intensity, while the polymeric micelles expressed strong red fluorescence. Furthermore, in flow cytometric analysis, fluorescence intensity of polymeric micelles was almost twice as high than with free doxorubicin.Conclusion: DexbLG polymeric micelles incorporating doxorubicin are promising vehicles for antitumor drug targeting.Keywords: dextran, polymeric micelle, block copolymer, poly(DL-lactide-co-glycolide
CT Findings of Completely Regressed Hepatocellular Carcinoma with Main Portal Vein Tumor Thrombosis after Transcatheter Arterial Chemoembolization
Objective: The objective of this study was to determine the sequential CT findings of controlled hepatocellular carcinoma (HCC) with main portal vein (MPV) thrombosis with the use of transcatheter arterial chemoembolization and additional intra-arterial cisplatin infusion. Materials and Methods: From January 2004 to September 2006, 138 patients with HCC invading MPV were referred to the angiography unit of our institution for chemoembolization and additional intra-arterial cisplatin infusion. Until August 2008, seven (5%) of 138 patients were followed-up and found not to have tumor recurrence. CT scans were retrospectively reviewed by two radiologists, focusing on the following parameters: the extent of portal vein thrombosis, the diameter of the affected portal vein, and enhancement of portal vein thrombosis. Results: The extent of portal vein thrombosis at the initial presentation was variable: left portal vein (LPV) and MPV (n = 1), right portal vein (RPV) and MPV (n = 3), as well as RPV, LPV and MPV (n = 3). The extent and diameter of the affected portal vein decreased during follow-up examinations. In addition, the degree of enhancement for tumor thrombi and serum alpha-feto-protein levels decreased after the transcatheter arterial chemoembolization. Portal vein thrombosis was found to be completely resolved in one patient, whereas residual thrombus without viability was persistent in six patients. Conclusion: If chemoembolization is effective in patients with HCC that invades the portal vein, the extent and enhancement of portal vein thrombosis is reduced, but residual thrombosis frequently persists for months or years, without evidence of a viable tumor.Shin SW, 2009, KOREAN J RADIOL, V10, P425, DOI 10.3348/kjr.2009.10.5.425El-Serag HB, 2008, GASTROENTEROLOGY, V134, P1752, DOI 10.1053/j.gastro.2008.02.090Shah ZK, 2007, AM J ROENTGENOL, V188, P1320, DOI 10.2214/AJR.06.0134JEON UB, 2007, RAD SOC N AM 93 SCIObi S, 2006, CANCER, V106, P1990, DOI 10.1002/cncr.21832MYUNG SJ, 2006, KOREAN J HEPATOL, V12, P107Georgiades CS, 2005, J VASC INTERV RADIOL, V16, P1653, DOI 10.1097/01.RVI.0000182185.47500.7AKim DY, 2005, CANCER, V103, P2419, DOI 10.1002/cncr.21043Llovet JM, 2003, HEPATOLOGY, V37, P429, DOI 10.1053/jhep.2003.50047Bruix J, 2001, J HEPATOL, V35, P421Lee HS, 1997, CANCER, V79, P2087Tublin ME, 1997, AM J ROENTGENOL, V168, P719CHUNG JW, 1995, AM J ROENTGENOL, V165, P315MATHIEU D, 1984, RADIOLOGY, V152, P127YAMADA R, 1983, RADIOLOGY, V148, P397
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