Hokkaido University

About: Hokkaido University is a education organization based out in Sapporo, Hokkaidô, Japan. It is known for research contribution in the topics: Catalysis & Population. The organization has 53925 authors who have published 115403 publications receiving 2651647 citations. The organization is also known as: Hokudai & Hokkaidō daigaku.

Radical scavenging and singlet oxygen quenching activity of marine carotenoid fucoxanthin and its metabolites.

Abstract: Antioxidant activity of carotenoids is suggested to be one of the factors for their disease preventing effects. Marine carotenoids fucoxanthin and its two metabolites, fucoxanthinol and halocynthiaxanthin, have been shown to exhibit several biological effects. The antioxidant activities of these three carotenoids were assessed in vitro with respect to radical scavenging and singlet oxygen quenching abilities. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of fucoxanthin and fucoxanthinol was higher than that of halocynthiaxanthin, with the effective concentration for 50% scavenging (EC 50) being 164.60, 153.78, and 826.39 microM, respectively. 2,2'-Azinobis-3-ethylbenzo thizoline-6-sulphonate radical scavenging activity of fucoxanthinol (EC 50, 2.49 microM) was stronger than that of fucoxanthin (EC 50, 8.94 microM). Hydroxyl radical scavenging activity as measured by the chemiluminescence technique showed that the scavenging activity of fucoxanthin was 7.9 times higher than that by fucoxanthinol, 16.3 times higher than that by halocynthiaxanthin, and 13.5 times higher than that by alpha-tocopherol. A similar trend was observed when the hydroxyl radical scavenging was assessed by the electron spin resonance (ESR) technique. ESR analysis of the superoxide radical scavenging activity also showed the superiority of fucoxanthin over the other two carotenoids tested. Singlet oxygen quenching ability of the three carotenoids was lower than that of beta-carotene, with quenching rate constants ( k Q, x10 (10) M (-1) s (-1)) being 1.19, 1.81, 0.80, and 12.78 for fucoxanthin, fucoxanthinol, halocynthiaxanthin, and beta-carotene, respectively. The higher radical scavenging activity of fucoxanthin and fucoxanthinol compared with halocynthiaxanthin is assumed to be due to presence of the allenic bond.

Clinical features of hepatocellular carcinoma with extrahepatic metastases

Abstract: Background: There are few detailed clinical reports about extrahepatic metastases of hepatocellular carcinoma (HCC). The purpose of the present study was to elucidate the clinical features of extrahepatic metastases of HCC. Methods: The clinical records of 482 patients who had been diagnosed as having HCC during the period from January 1995 to March 2001 were retrospectively reviewed. Extrahepatic metastases had been detected in 65 patients. Clinical features of those 65 patients were analyzed. Results: Patients with extrahepatic metastases had more advanced intrahepatic tumors at the first diagnosis of HCC: 73.8% of the patients with extrahepatic metastases had tumors of intrahepatic tumor stage T3 or T4 according to the TNM classification, while only 28.5% of the patients without extrahepatic metastases had tumors of T3 or T4 (P < 0.001). Vessel invasion was also detected at the first diagnosis of HCC more frequently in the patients with extrahepatic metastasis (P < 0.001). The frequent metastatic sites were lung (53.8%), bone (38.5%), and lymph node (33.8%). Other metastatic sites were the adrenal gland, peritoneum, skin, brain and muscle. The median survival time and 1-year survival rate were 7 months (range: 1–59 months) and 24.9%, respectively. Patients with Child–Pugh grade B and C (P = 0.0018) and patients with positive serum α-fetoprotein (P = 0.011) had significantly poor prognosis. Conclusions: Extrahepatic metastases of HCC are not rare. The possibility of extrahepatic metastases and the clinical features of extrahepatic metastases should be considered when examining patients with HCC, particularly those with advanced intrahepatic tumors, to enable precise evaluation of the spread of HCC and determination of the appropriate treatment method. © 2005 Blackwell Publishing Asia Pty Ltd

Assessment of 68Ga-PSMA-11 PET Accuracy in Localizing Recurrent Prostate Cancer: A Prospective Single-Arm Clinical Trial

Abstract: Importance: In retrospective studies, 68Ga-PSMA-11 positron emission tomographic (PET) imaging improves detection of biochemically recurrent prostate cancer compared with conventional imaging. Objective: To assess 68Ga-PSMA-11 PET accuracy in a prospective multicenter trial. Design, Setting, and Participants: In this single-arm prospective trial conducted at University of California, San Francisco and University of California, Los Angeles, 635 patients with biochemically recurrent prostate cancer after prostatectomy (n = 262, 41%), radiation therapy (n = 169, 27%), or both (n = 204, 32%) underwent 68Ga-PSMA-11 PET. Presence of prostate cancer was recorded by 3 blinded readers on a per-patient and per-region base. Lesions were validated by histopathologic analysis and a composite reference standard. Main Outcomes and Measures: Endpoints were positive predictive value (PPV), detection rate, interreader reproducibility, and safety. Results: A total of 635 men were enrolled with a median age of 69 years (range, 44-95 years). On a per-patient basis, PPV was 0.84 (95% CI, 0.75-0.90) by histopathologic validation (primary endpoint, n = 87) and 0.92 (95% CI, 0.88-0.95) by the composite reference standard (n = 217). 68Ga-PSMA-11 PET localized recurrent prostate cancer in 475 of 635 (75%) patients; detection rates significantly increased with prostate-specific antigen (PSA): 38% for <0.5 ng/mL (n = 136), 57% for 0.5 to <1.0 ng/mL (n = 79), 84% for 1.0 to <2.0 ng/mL (n = 89), 86% for 2.0 to <5.0 ng/mL (n = 158), and 97% for ≥5.0 ng/mL (n = 173, P < .001). Interreader reproducibility was substantial (Fleiss κ, 0.65-0.78). There were no serious adverse events associated with 68Ga-PSMA-11 administration. PET-directed focal therapy alone led to a PSA drop of 50% or more in 31 of 39 (80%) patients. Conclusions and Relevance: Using blinded reads and independent lesion validation, we establish high PPV for 68Ga-PSMA-11 PET, detection rate and interreader agreement for localization of recurrent prostate cancer. Trial Registration: ClinicalTrials.gov Identifiers: NCT02940262 and NCT03353740.