1
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Ohe Y, Ohashi Y, Kubota K, Tamura T, Nakagawa K, Negoro S, Nishiwaki Y, Saijo N, Ariyoshi Y, Fukuoka M. Randomized phase III study of cisplatin plus irinotecan versus carboplatin plus paclitaxel, cisplatin plus gemcitabine, and cisplatin plus vinorelbine for advanced non-small-cell lung cancer: Four-Arm Cooperative Study in Japan. Ann Oncol 2006; 18:317-23. [PMID: 17079694 DOI: 10.1093/annonc/mdl377] [Citation(s) in RCA: 480] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND To compare the efficacy and toxicity of three platinum-based combination regimens against cisplatin plus irinotecan (IP) in patients with untreated advanced non-small-cell lung cancer (NSCLC) by a non-inferiority design. PATIENTS AND METHODS A total of 602 patients were randomly assigned to one of four regimens: cisplatin 80 mg/m(2) on day 1 plus irinotecan 60 mg/m(2) on days 1, 8, 15 every 4 weeks (IP) carboplatin AUC 6.0 min x mg/mL (area under the concentration-time curve) on day 1 plus paclitaxel 200 mg/m(2) on day 1 every 3 weeks (TC); cisplatin 80 mg/m(2) on day 1 plus gemcitabine 1000 mg/m(2) on days 1, 8 every 3 weeks (GP); and cisplatin 80 mg/m(2) on day 1 plus vinorelbine 25 mg/m(2) on days 1, 8 every 3 weeks (NP). RESULTS The response rate, median survival time, and 1-year survival rate were 31.0%, 13.9 months, 59.2%, respectively, in IP; 32.4%, 12.3 months, 51.0% in TC; 30.1%, 14.0 months, 59.6% in GP; and 33.1%, 11.4 months, 48.3% in NP. No statistically significant differences were found in response rate or overall survival, but the non-inferiority of none of the experimental regimens could be confirmed. All the four regimens were well tolerated. CONCLUSION The four regimens have similar efficacy and different toxicity profiles, and they can be used to treat advanced NSCLC patients.
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Research Support, Non-U.S. Gov't |
19 |
480 |
2
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Tsutsumi Y, Matsubara H, Masaki H, Kurihara H, Murasawa S, Takai S, Miyazaki M, Nozawa Y, Ozono R, Nakagawa K, Miwa T, Kawada N, Mori Y, Shibasaki Y, Tanaka Y, Fujiyama S, Koyama Y, Fujiyama A, Takahashi H, Iwasaka T. Angiotensin II type 2 receptor overexpression activates the vascular kinin system and causes vasodilation. J Clin Invest 1999; 104:925-35. [PMID: 10510333 PMCID: PMC408562 DOI: 10.1172/jci7886] [Citation(s) in RCA: 414] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/1999] [Accepted: 08/25/1999] [Indexed: 11/17/2022] Open
Abstract
Angiotensin II (Ang II) is a potent vasopressor peptide that interacts with 2 major receptor isoforms - AT1 and AT2. Although blood pressure is increased in AT2 knockout mice, the underlying mechanisms remain undefined because of the low levels of expression of AT2 in the vasculature. Here we overexpressed AT2 in vascular smooth muscle (VSM) cells in transgenic (TG) mice. Aortic AT1 was not affected by overexpression of AT2. Chronic infusion of Ang II into AT2-TG mice completely abolished the AT1-mediated pressor effect, which was blocked by inhibitors of bradykinin type 2 receptor (icatibant) and nitric oxide (NO) synthase (L-NAME). Aortic explants from TG mice showed greatly increased cGMP production and diminished Ang II-induced vascular constriction. Removal of endothelium or treatment with icatibant and L-NAME abolished these AT2-mediated effects. AT2 blocked the amiloride-sensitive Na(+)/H(+) exchanger, promoting intracellular acidosis in VSM cells and activating kininogenases. The resulting enhancement of aortic kinin formation in TG mice was not affected by removal of endothelium. Our results suggest that AT2 in aortic VSM cells stimulates the production of bradykinin, which stimulates the NO/cGMP system in a paracrine manner to promote vasodilation. Selective stimulation of AT2 in the presence of AT1 antagonists is predicted to have a beneficial clinical effect in controlling blood pressure.
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MESH Headings
- Actins/genetics
- Amiloride/pharmacology
- Angiotensin II/pharmacology
- Animals
- Aorta/physiology
- Blood Pressure/physiology
- Bradykinin/analogs & derivatives
- Bradykinin/pharmacology
- Bradykinin/physiology
- Bradykinin Receptor Antagonists
- Cell Membrane/physiology
- Cyclic GMP/metabolism
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/physiology
- Imidazoles/pharmacology
- Kinins/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- NG-Nitroarginine Methyl Ester
- Promoter Regions, Genetic
- Pyridines/pharmacology
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptors, Angiotensin/deficiency
- Receptors, Angiotensin/genetics
- Receptors, Angiotensin/physiology
- Recombinant Fusion Proteins/metabolism
- Tunica Media/physiology
- Vasoconstriction
- Vasodilation/drug effects
- Vasodilation/physiology
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research-article |
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414 |
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Masuda N, Fukuoka M, Kusunoki Y, Matsui K, Takifuji N, Kudoh S, Negoro S, Nishioka M, Nakagawa K, Takada M. CPT-11: a new derivative of camptothecin for the treatment of refractory or relapsed small-cell lung cancer. J Clin Oncol 1992; 10:1225-9. [PMID: 1321891 DOI: 10.1200/jco.1992.10.8.1225] [Citation(s) in RCA: 296] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
PURPOSE To evaluate the activity of CPT-11, which is a new derivative of camptothecin, against refractory or relapsed small-cell lung cancer (SCLC). PATIENTS AND METHODS Sixteen patients with refractory or relapsed SCLC were entered onto a prospective, non-randomized, single-institution phase II trial. All 16 patients had been pretreated heavily with some form of cisplatin-based combination chemotherapy. Five patients had received previous chemotherapy with cisplatin, vincristine, doxorubicin, and etoposide (CODE) as an induction therapy. Six patients had been treated with concurrent cisplatin and etoposide plus chest x-ray. The median time off chemotherapy was 7.3 months (range, 1.9 to 15.1 months). Patients were treated with a CPT-11 starting dose of 100 mg/m2 body surface given as a 90-minute intravenous (IV) infusion every week with subsequent doses based on toxicity. Fifteen patients were assessable for toxicity, response, and survival. RESULTS Seven patients (47%; 95% confidence limits for an overall response rate, 21.4% to 71.9%) responded to CPT-11 with a median duration of response of 58 days. The major toxicities were myelosuppression (predominantly leukopenia), diarrhea, and pulmonary toxicity. CONCLUSION CPT-11 is an active agent against refractory or relapsed SCLC and deserves to be studied more closely as both a single agent and in combination with other drugs to treat patients with SCLC.
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296 |
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Strobl S, Fernandez-Catalan C, Braun M, Huber R, Masumoto H, Nakagawa K, Irie A, Sorimachi H, Bourenkow G, Bartunik H, Suzuki K, Bode W. The crystal structure of calcium-free human m-calpain suggests an electrostatic switch mechanism for activation by calcium. Proc Natl Acad Sci U S A 2000; 97:588-92. [PMID: 10639123 PMCID: PMC15374 DOI: 10.1073/pnas.97.2.588] [Citation(s) in RCA: 268] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Calpains (calcium-dependent cytoplasmic cysteine proteinases) are implicated in processes such as cytoskeleton remodeling and signal transduction. The 2.3-A crystal structure of full-length heterodimeric [80-kDa (dI-dIV) + 30-kDa (dV+dVI)] human m-calpain crystallized in the absence of calcium reveals an oval disc-like shape, with the papain-like catalytic domain dII and the two calmodulin-like domains dIV+dVI occupying opposite poles, and the tumor necrosis factor alpha-like beta-sandwich domain dIII and the N-terminal segments dI+dV located between. Compared with papain, the two subdomains dIIa+dIIb of the catalytic unit are rotated against one another by 50 degrees, disrupting the active site and the substrate binding site, explaining the inactivity of calpains in the absence of calcium. Calcium binding to an extremely negatively charged loop of domain dIII (an electrostatic switch) could release the adjacent barrel-like subdomain dIIb to move toward the helical subdomain dIIa, allowing formation of a functional catalytic center. This switch loop could also mediate membrane binding, thereby explaining calpains' strongly reduced calcium requirements in vivo. The activity status at the catalytic center might be further modulated by calcium binding to the calmodulin domains via the N-terminal linkers.
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research-article |
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268 |
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Nakagawa K, Tamura T, Negoro S, Kudoh S, Yamamoto N, Yamamoto N, Takeda K, Swaisland H, Nakatani I, Hirose M, Dong RP, Fukuoka M. Phase I pharmacokinetic trial of the selective oral epidermal growth factor receptor tyrosine kinase inhibitor gefitinib ('Iressa', ZD1839) in Japanese patients with solid malignant tumors. Ann Oncol 2003; 14:922-30. [PMID: 12796031 DOI: 10.1093/annonc/mdg250] [Citation(s) in RCA: 239] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND This phase I dose-escalating study investigated the tolerability and toxicity of the selective epidermal growth factor receptor tyrosine kinase inhibitor gefitinib ('Iressa', ZD1839) in Japanese patients with solid tumors. Thirty-one patients were included. PATIENTS AND METHODS Patients initially received a single oral dose of gefitinib followed by 10-14 days of observation. Oral gefitinib was subsequently administered on 14 consecutive days, every 28 days. Dose escalation was from 50 mg/day to a maximum of 925 mg/day or dose-limiting toxicity (DLT). RESULTS Most adverse events were mild (grade 1/2); the most frequent were an acne-like rash and gastrointestinal effects. Two of six patients at 700 mg/day had DLT; no further dose escalation occurred. C(max) was reached within 3-7 h and exposure to gefitinib increased with dose. Mean terminal half-life following multiple dosing was 50.1 h (range 27.8-79.7 h). A partial response (duration 35-361 days) was observed in five of the 23 patients with non-small-cell lung cancer over a range of doses (225-700 mg/day), and seven patients with a range of tumors had disease stabilization (duration 40-127 days). CONCLUSIONS In conclusion, gefitinib showed a favorable tolerability profile in Japanese patients. The safety profile, pharmacokinetic parameters and antitumor activity observed in our study are comparable to those observed in patients from the USA and Europe.
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Clinical Trial |
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239 |
6
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Haratani K, Hayashi H, Tanaka T, Kaneda H, Togashi Y, Sakai K, Hayashi K, Tomida S, Chiba Y, Yonesaka K, Nonagase Y, Takahama T, Tanizaki J, Tanaka K, Yoshida T, Tanimura K, Takeda M, Yoshioka H, Ishida T, Mitsudomi T, Nishio K, Nakagawa K. Tumor immune microenvironment and nivolumab efficacy in EGFR mutation-positive non-small-cell lung cancer based on T790M status after disease progression during EGFR-TKI treatment. Ann Oncol 2018; 28:1532-1539. [PMID: 28407039 DOI: 10.1093/annonc/mdx183] [Citation(s) in RCA: 239] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Indexed: 12/22/2022] Open
Abstract
Background The efficacy of programmed death-1 blockade in epidermal growth factor receptor gene (EGFR) mutation-positive non-small-cell lung cancer (NSCLC) patients with different mechanisms of acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) is unknown. We retrospectively evaluated nivolumab efficacy and immune-related factors in such patients according to their status for the T790M resistance mutation of EGFR. Patients and methods We identified 25 patients with EGFR mutation-positive NSCLC who were treated with nivolumab after disease progression during EGFR-TKI treatment (cohort A). Programmed death-ligand 1 (PD-L1) expression and tumor-infiltrating lymphocyte (TIL) density in tumor specimens obtained after acquisition of EGFR-TKI resistance were determined by immunohistochemistry. Whole-exome sequencing of tumor DNA was carried out to identify gene alterations. The relation of T790M status to PD-L1 expression or TIL density was also examined in an independent cohort of 60 patients (cohort B). Results In cohort A, median progression-free survival (PFS) was 2.1 and 1.3 months for T790M-negative and T790M-positive patients, respectively (P = 0.099; hazard ratio of 0.48 with a 95% confidence interval of 0.20-1.24). Median PFS was 2.1 and 1.3 months for patients with a PD-L1 expression level of ≥1% or <1%, respectively (P = 0.084; hazard ratio of 0.37, 95% confidence interval of 0.10-1.21). PFS tended to increase as the PD-L1 expression level increased with cutoff values of ≥10% and ≥50%. The proportion of tumors with a PD-L1 level of ≥10% or ≥50% was higher among T790M-negative patients than among T790M-positive patients of both cohorts A and B. Nivolumab responders had a significantly higher CD8+ TIL density and nonsynonymous mutation burden. Conclusion T790M-negative patients with EGFR mutation-positive NSCLC are more likely to benefit from nivolumab after EGFR-TKI treatment, possibly as a result of a higher PD-L1 expression level, than are T790M-positive patients.
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Journal Article |
7 |
239 |
7
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Arase H, Arase N, Nakagawa K, Good RA, Onoé K. NK1.1+ CD4+ CD8- thymocytes with specific lymphokine secretion. Eur J Immunol 1993; 23:307-10. [PMID: 8419184 DOI: 10.1002/eji.1830230151] [Citation(s) in RCA: 219] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
CD4+8- or CD4-8+ thymocytes have been regarded as direct progenitors of peripheral T cells. However, recently, we have found a novel NK1.1+ subpopulation with skewed T cell antigen receptor (TcR) V beta family among heat-stable antigen negative (HSA-) CD4+8- thymocytes. In the present study, we show that these NK1.1+ CD4+8- thymocytes, which represent a different lineage from the major NK1.1- CD4+8- thymocytes or CD4+ lymph node T cells, vigorously secrete interleukin (IL)-4 and interferon (IFN)-gamma upon stimulation with immobilized anti-TcR-alpha beta antibody. On the other hand, neither NK1.1- CD4+8- thymocytes nor CD4+ lymph node T cells produced substantial amounts of these lymphokines. A similar pattern of lymphokine secretion was observed with the NK1.1+ CD4+T cells obtained from bone marrow. The present findings elucidate the recent observations that HSA- CD4+8- thymocytes secrete a variety of lymphokines including IFN-gamma, IL-4, IL-5 and IL-10 before the CD4+8- thymocytes are exported from thymus. Our evidence indicates that NK1.1+ CD4+8- thymocytes are totally responsible for the specific lymphokine secretions observed in the HSA- CD4+8- thymocytes.
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219 |
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Nakagawa K, Okuda S, Miyazawa T. Dose-dependent incorporation of tea catechins, (-)-epigallocatechin-3-gallate and (-)-epigallocatechin, into human plasma. Biosci Biotechnol Biochem 1997; 61:1981-5. [PMID: 9438978 DOI: 10.1271/bbb.61.1981] [Citation(s) in RCA: 201] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Tea catechins, (-)-epigallocatechin-3-gallate (EGCg) and (-)-epigallocatechin (EGC), have been reported to suppress oxidation of plasma low density lipoprotein (LDL) in vitro. If dietary catechins can be efficiently incorporated into human blood plasma, anti-atherosclerotic effects in preventing oxidative modification of LDL would be expected. In this study, a newly developed chemiluminescence detection-high pressure liquid chromatography (CL-HPLC) method for measuring plasma catechins was used and the incorporation of EGCg and EGC into human plasma was investigated. Healthy subjects orally ingested 3, 5, or 7 capsules of green tea extract (corresponding to 225, 375, and 525 mg EGCg and 7.5, 12.5, and 17.5 mg EGC, respectively). The plasma EGCg and EGC concentrations before the administration were all below the detection limit (< 2 pmol/ml), but 90 min after, significantly and dose-dependently increased to 657, 4300, and 4410 pmol EGCg/ml, and 35, 144, and 255 pmol EGC/ml, in the subjects who received 3, 5, and 7 capsules, respectively. Both EGCg and EGC levels detected in plasma corresponded to 0.2-2.0% of the ingested amount. Catechin intake had no effect on the basal level of endogenous antioxidants (alpha-tocopherol, beta-carotene, and lycopene) or of lipids in plasma. These results suggested that drinking green tea daily would contribute to maintain plasma catechin levels sufficient to exert antioxidant activity against oxidative modification of lipoproteins in blood circulation systems.
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Clinical Trial |
28 |
201 |
9
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Spigel DR, Vicente D, Ciuleanu TE, Gettinger S, Peters S, Horn L, Audigier-Valette C, Pardo Aranda N, Juan-Vidal O, Cheng Y, Zhang H, Shi M, Luft A, Wolf J, Antonia S, Nakagawa K, Fairchild J, Baudelet C, Pandya D, Doshi P, Chang H, Reck M. Second-line nivolumab in relapsed small-cell lung cancer: CheckMate 331 ☆. Ann Oncol 2021; 32:631-641. [PMID: 33539946 DOI: 10.1016/j.annonc.2021.01.071] [Citation(s) in RCA: 188] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/13/2021] [Accepted: 01/17/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Patients with relapsed small-cell lung cancer (SCLC) have few treatment options and dismal survival. Phase I/II data show activity of nivolumab in previously treated SCLC. PATIENTS AND METHODS CheckMate 331 is a randomized, open-label, phase III trial of nivolumab versus standard chemotherapy in relapsed SCLC. Patients with relapse after first-line, platinum-based chemotherapy were randomized 1 : 1 to nivolumab 240 mg every 2 weeks or chemotherapy (topotecan or amrubicin) until progression or unacceptable toxicity. Primary endpoint was overall survival (OS). RESULTS Overall, 284 patients were randomized to nivolumab and 285 to chemotherapy. Minimum follow-up was 15.8 months. No significant improvement in OS was seen with nivolumab versus chemotherapy [median OS, 7.5 versus 8.4 months; hazard ratio (HR), 0.86; 95% confidence interval (CI), 0.72-1.04; P = 0.11]. A survival benefit with nivolumab was suggested in patients with baseline lactate dehydrogenase ≤ upper limit of normal and in those without baseline liver metastases. OS (nivolumab versus chemotherapy) was similar in patients with programmed death-ligand 1 combined positive score ≥1% versus <1%. Median progression-free survival was 1.4 versus 3.8 months (HR, 1.41; 95% CI, 1.18-1.69). Objective response rate was 13.7% versus 16.5% (odds ratio, 0.80; 95% CI, 0.50-1.27); median duration of response was 8.3 versus 4.5 months. Rates of grade 3 or 4 treatment-related adverse events were 13.8% versus 73.2%. CONCLUSION Nivolumab did not improve survival versus chemotherapy in relapsed SCLC. No new safety signals were seen. In exploratory analyses, select baseline characteristics were associated with improved OS for nivolumab.
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Research Support, Non-U.S. Gov't |
4 |
188 |
10
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Nakagawa K, Miyazawa T. Absorption and distribution of tea catechin, (-)-epigallocatechin-3-gallate, in the rat. J Nutr Sci Vitaminol (Tokyo) 1997; 43:679-84. [PMID: 9530620 DOI: 10.3177/jnsv.43.679] [Citation(s) in RCA: 179] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
To investigate the absorption and metabolism of an anticarcinogenic tea catechin, (-)-epigallocatechin-3-gallate (EGCg), in rats, a newly developed chemiluminescence-detection high-performance liquid chromatography (CL-HPLC) method was employed and the EGCg concentrations in blood plasma, liver, brain, small intestinal mucosa and colon mucosa were determined before and after EGCg administration. The recovery of EGCg, extracted consecutively with ethyl acetate and methanol, was 86.1% from plasma and 64.5-74.2% from the tissue samples. The EGCg concentrations of plasma and tissue samples from the control rat (before EGCg administration) were all below the detection limit (< 0.002 nmol/mL, 0.002 nmol/g), but 60 min after a single oral administration of EGCg (500 mg/kg body weight), the levels increased, reaching 12.3 nmol/mL in plasma, 48.4 nmol/g in liver, 0.5 nmol/g in brain, 565 nmol/g in small intestinal mucosa and 68.6 nmol/g in colon mucosa. The EGCg levels found in the tissues corresponded to 0.0003-0.45% of ingested EGCg. The results indicate that tea catechin, EGCg, is absorbed from the digestive tract, with the intestinal mucosa the most enriched of the organelles. This may explain the potent antioxidant function of EGCg in inhibiting colon mucosal phospholipid hydroperoxidation in the prevention of rat colonic carcinogenesis.
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179 |
11
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Shirai N, Furuta T, Moriyama Y, Okochi H, Kobayashi K, Takashima M, Xiao F, Kosuge K, Nakagawa K, Hanai H, Chiba K, Ohashi K, Ishizaki T. Effects of CYP2C19 genotypic differences in the metabolism of omeprazole and rabeprazole on intragastric pH. Aliment Pharmacol Ther 2001; 15:1929-37. [PMID: 11736724 DOI: 10.1046/j.1365-2036.2001.01108.x] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Omeprazole is mainly metabolized in the liver by CYP2C19, a genetically determined enzyme, whereas rabeprazole is mainly reduced non-enzymatically and partially metabolized by CYP2C19. The therapeutic effects of rabeprazole are therefore assumed to be less affected by an individual's CYP2C19 status. AIM To investigate the acid inhibitory effects and plasma levels of omeprazole and rabeprazole with reference to different CYP2C19 genotypes. METHODS Fifteen healthy volunteers took a daily dose of 20 mg of omeprazole or rabeprazole for 8 days. On post-dose days 1 and 8, 24-h profiles of intragastric pH were recorded and plasma concentrations of omeprazole, rabeprazole and their metabolites were determined. RESULTS After single and repeated doses of omeprazole, the intragastric pH values and plasma concentrations of omeprazole and its metabolites were significantly dependent on the CYP2C19 genotype. Significant differences in the same kinetic and dynamic parameters were also observed after single doses of rabeprazole. Although the plasma levels of rabeprazole differed among the different CYP2C19 genotype groups after repeated doses, no significant differences in intragastric pH values were observed. CONCLUSIONS The acid inhibitory effects of omeprazole and rabeprazole are significantly dependent on the CYP2C19 genotype status, as well as on their intrinsic pharmacokinetic and pharmacodynamic characteristics and dosing schemes.
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Clinical Trial |
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162 |
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Omoto Y, Kobayashi Y, Nishida K, Tsuchiya E, Eguchi H, Nakagawa K, Ishikawa Y, Yamori T, Iwase H, Fujii Y, Warner M, Gustafsson JA, Hayashi SI. Expression, function, and clinical implications of the estrogen receptor beta in human lung cancers. Biochem Biophys Res Commun 2001; 285:340-7. [PMID: 11444848 DOI: 10.1006/bbrc.2001.5158] [Citation(s) in RCA: 155] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The higher frequency of human lung adenocarcinoma in females than in males, strongly suggests the involvement of gender dependent factors in the etiology of this disease. This is the first investigation of estrogen receptor (ER) beta in human lung. Immunohistochemical staining revealed ERbeta expression in normal lung and in atypical adenomatous hyperplasia (AAH), considered as a precancerous lesion for adenocarcinomas. Adenocarcinomas showed significantly higher expression of ERbeta than squamous cell carcinomas. On the contrary, ERalpha expression was not detected in all cases. The functional integrity of ERbeta such as the binding ability to estrogen responsive element (ERE) and transcriptional activity was confirmed using a human lung cancer cell line, RERF-LC-OK. Colony formation of this cell was significantly reduced in the presence of pure antiestrogen. We conclude that ERbeta, but not ERalpha, is present in lung tissues with an important physiological function in normal lung. Furthermore, ERbeta may play a role in growth and development of adenocarcinomas.
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Ishibashi T, Hata Y, Yoshikawa H, Nakagawa K, Sueishi K, Inomata H. Expression of vascular endothelial growth factor in experimental choroidal neovascularization. Graefes Arch Clin Exp Ophthalmol 1997; 235:159-67. [PMID: 9085111 DOI: 10.1007/bf00941723] [Citation(s) in RCA: 154] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Although the choroidal neovascularization (CNV) is a common pathologic feature of a number of different eye diseases, its pathological mechanisms have not been fully elucidated. We investigated the expression of vascular endothelial growth factor (VEGF) in CNV using an experimental primate model. METHOD CNV was induced by intense laser photocoagulation in four monkey eyes. Single eyes were enucleated at 1, 3, 7 or 14 days after photocoagulation and examined immunohistochemically for VEGF, macrophage antigen, von Willebrand factor and glial fibrillary acidic protein (GFAP). Expression of VEGF mRNA was examined by in situ hybridization. RESULTS One day after photocoagulation, the normal structure of the outer portion of the retina and the inner portion of the choroid was destroyed. Three days after photocoagulation, choroidal vascular endothelial cells migrated into the subretinal space through the defect in Bruch's membrane. Increased expression of VEGF was detected in the accumulating macrophages, migrating retinal pigment epithelial (RPE) cells and Müller cells. Maximal expression of VEGF was observed between 3 and 7 days after wounding, and many newly formed vessels extended into the subretinal space 7-14 days after photocoagulation. CONCLUSION VEGF derived from RPE cells, macrophages and Müller cells may play a role in the formation of CNV.
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Abstract
Coronaviruses have large positive-strand RNA genomes that are 5' capped and 3' polyadenylated. The 5'-terminal two-thirds of the genome contain two open reading frames (ORFs), 1a and 1b, that together make up the viral replicase gene and encode two large polyproteins that are processed by viral proteases into 15-16 nonstructural proteins, most of them being involved in viral RNA synthesis. ORFs located in the 3'-terminal one-third of the genome encode structural and accessory proteins and are expressed from a set of 5' leader-containing subgenomic mRNAs that are synthesized by a process called discontinuous transcription. Coronavirus protein synthesis not only involves cap-dependent translation mechanisms but also employs regulatory mechanisms, such as ribosomal frameshifting. Coronavirus replication is known to affect cellular translation, involving activation of stress-induced signaling pathways, and employing viral proteins that affect cellular mRNA translation and RNA stability. This chapter describes our current understanding of the mechanisms involved in coronavirus mRNA translation and changes in host mRNA translation observed in coronavirus-infected cells.
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Review |
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151 |
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Nakagawa K, Saijo N, Tsuchida S, Sakai M, Tsunokawa Y, Yokota J, Muramatsu M, Sato K, Terada M, Tew KD. Glutathione-S-transferase pi as a determinant of drug resistance in transfectant cell lines. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39562-6] [Citation(s) in RCA: 145] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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145 |
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Yoshikawa N, Ito H, Sakai T, Takekoshi Y, Honda M, Awazu M, Ito K, Iitaka K, Koitabashi Y, Yamaoka K, Nakagawa K, Nakamura H, Matsuyama S, Seino Y, Takeda N, Hattori S, Ninomiya M. A controlled trial of combined therapy for newly diagnosed severe childhood IgA nephropathy. The Japanese Pediatric IgA Nephropathy Treatment Study Group. J Am Soc Nephrol 1999; 10:101-9. [PMID: 9890315 DOI: 10.1681/asn.v101101] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The most appropriate treatment for patients with IgA nephropathy is controversial. Treatment with prednisolone, azathioprine, heparin-warfarin, and dipyridamole early in the course of disease may prevent immunologic renal injury in children with severe IgA nephropathy. To determine whether similar results can be obtained with a combination of just heparin-warfarin and dipyridamole, the effects of such treatment were compared to those of treatment with prednisolone, azathioprine, heparin-warfarin, and dipyridamole in 78 children with newly diagnosed IgA nephropathy showing diffuse mesangial proliferation. The patients were randomly assigned to receive either prednisolone, azathioprine, heparin-warfarin, and dipyridamole for 2 yr (group 1) or heparin-warfarin and dipyridamole for 2 yr (group 2). All of the 40 patients in group 1 and 34 of the 38 patients in group 2 completed the trial. The mean urinary protein excretion fell in group 1 patients (P < 0.0001), but remained unchanged in group 2 patients. The mean serum IgA concentration was reduced in group 1 patients (P = 0.0002), but was unchanged in group 2 patients. BP and creatinine clearance were normal at the end of the trial in all but one group 2 patient, who developed chronic renal insufficiency. The percentage of glomeruli showing sclerosis was unchanged in group 1 patients, but increased in group 2 patients (P = 0.006). The intensity of mesangial IgA deposits decreased in group 1 patients (P = 0.02), but remained unchanged in group 2 patients. In conclusion, the present study shows that treatment of children with severe IgA nephropathy with prednisolone, azathioprine, heparin-warfarin, and dipyridamole for 2 yr early in the course of disease reduces immunologic renal injury and prevents increase of sclerosed glomeruli.
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Ambiru S, Miyazaki M, Isono T, Ito H, Nakagawa K, Shimizu H, Kusashio K, Furuya S, Nakajima N. Hepatic resection for colorectal metastases: analysis of prognostic factors. Dis Colon Rectum 1999; 42:632-9. [PMID: 10344686 DOI: 10.1007/bf02234142] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE Hepatic resection affords the best hope of survival for patients with colorectal carcinoma metastatic to the liver. However, recurrences are observed in about 60 percent of patients after curative hepatic resection. The purpose of this study was to examine the prognostic factors of patients undergoing curative hepatic resection for colorectal metastases. METHODS Between April 1984 and September 1997, 168 patients underwent curative hepatic resection for colorectal metastases. The clinicopathologic factors studied for prognostic value were gender, age, primary site, nodal status of primary tumor, time of metastases, preoperative serum level of carcinoembryonic antigen, hepatic tumor size and distribution, number of metastases, type of hepatic resection, resection margin, presence of micrometastases in resected specimen and microscopic fibrous pseudocapsule between the hepatic tumor and surrounding hepatic parenchyma, nodal status of hepatoduodenal ligament, adjuvant regional chemotherapy, and perioperative transfusion. RESULTS The overall survival was 42 percent at three years and 26 percent at five years, including a 3.5 percent 60-day surgical mortality rate. Thirty-one percent of patients had micrometastases located at a median distance of 3 mm from the metastatic tumor edge. Presence of microscopic fibrous pseudocapsule was observed in 28 percent of patients. Univariate and multivariate analyses showed that significant prognostic factors for survival were nodal status of primary tumor, number of metastases, resection margin, microscopic fibrous pseudocapsule, and adjuvant regional chemotherapy. CONCLUSIONS We conclude that 1) hepatic resection is effective in select patients with colorectal metastases; 2) adequate resection margin and adjuvant regional chemotherapy can improve outcome; and 3) microscopic fibrous pseudocapsule may offer additional postoperative information as an independent prognostic factor.
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Moore MA, Nakagawa K, Satoh K, Ishikawa T, Sato K. Single GST-P positive liver cells--putative initiated hepatocytes. Carcinogenesis 1987; 8:483-6. [PMID: 3815743 DOI: 10.1093/carcin/8.3.483] [Citation(s) in RCA: 133] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Immunohistochemical investigation of liver tissue 48 h after single doses of the hepatocarcinogens diethylnitrosamine (DEN), dimethylnitrosamine, aflatoxin B1 and methylazoxymethanol acetate revealed the generation of a population of single glutathione S-transferase placental form (GST-P) positive hepatocytes. Yield was carcinogen dose dependent. Although the mixed function enzyme inducers sodium phenobarbital (PB), methylcholanthrene (Mech), polychlorinated biphenyls (PCB) and isosafrole (IS) did not in themselves induce comparable single cell lesions, their application prior to DEN caused significant alteration in the resultant numbers of GST-P positive hepatocytes observed. While PB and IS were associated with decreased yield, Mech and PCB, in contrast, brought about an increase. The results gained from investigation of the effects of 3-aminobenzamide administration and partial hepatectomy carried out at different times after carcinogen treatment also pointed to an 'initiated' character for the lesions and suggest that GST-P may be a useful marker for analyzing factors relevant to the initiation stage of hepatocarcinogenesis. Thus the interplay between carcinogen metabolism, DNA adduct formation and repair, toxicity and proliferation may be assessable in terms of numbers of enzyme-altered solitary hepatocytes.
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Kondo M, Sakuta K, Noguchi A, Ariyoshi N, Sato K, Sato S, Sato K, Hosoi A, Nakajima J, Yoshida Y, Shiraishi K, Nakagawa K, Kakimi K. Zoledronate facilitates large-scale ex vivo expansion of functional gammadelta T cells from cancer patients for use in adoptive immunotherapy. Cytotherapy 2008; 10:842-856. [PMID: 19016372 DOI: 10.1080/14653240802419328] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Human gammadelta T cells can be activated by phospho-antigens and aminobisphosphonates such as zoledronate. Because they can kill tumor cells in a major histocompatibility complex (MHC)-unrestricted manner, adoptive transfer of activated gammadelta T cells may represent a novel cancer immunotherapy. We tested whether gammadelta T cells from advanced cancer patients can be expanded by zoledronate. METHODS Peripheral blood mononuclear cells from healthy donors and patients with advanced non-small cell lung cancer, bone metastatic breast or prostate cancer, or lung metastatic colorectal cancer, were stimulated with zoledronate (5 microM) and interleukin (IL)-2 (1000 IU/mL) for 14 days. The phenotype and function of the expanded gammadelta T-cell populations from healthy donors and cancer patients were compared. RESULTS Gammadelta T cells from cancer patients and healthy donors responded to zoledronate equally well in terms of both phenotype and function. gammadelta T cells grew rapidly in vitro and expression of effector molecules, such as interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, perforin, granzyme B, FasL and TRAIL, increased over time. Cytotoxicity peaked on days 12-14, and proliferation continued up to 14 days, during which time>1x10(9) gammadelta T cells could be obtained from a starting sample of 45-70 mL peripheral blood. DISCUSSION Using the agent zoledronate, already widely used in the clinic, we have established that efficient large-scale ex vivo expansion of gammadelta T cells from cancer patients is possible. These cells exert potent cytotoxicity and may be used for autologous cellular immunotherapy of cancer.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Bone Neoplasms/immunology
- Bone Neoplasms/secondary
- Bone Neoplasms/therapy
- Breast Neoplasms/immunology
- Breast Neoplasms/pathology
- Breast Neoplasms/therapy
- Carcinoma, Non-Small-Cell Lung/immunology
- Carcinoma, Non-Small-Cell Lung/pathology
- Carcinoma, Non-Small-Cell Lung/therapy
- Cell Proliferation/drug effects
- Cells, Cultured
- Colorectal Neoplasms/immunology
- Colorectal Neoplasms/pathology
- Colorectal Neoplasms/therapy
- Cytokines/genetics
- Cytokines/metabolism
- Cytotoxicity, Immunologic/drug effects
- Diphosphonates/pharmacology
- Female
- Humans
- Imidazoles/pharmacology
- Immunophenotyping
- Immunotherapy, Adoptive
- Lung Neoplasms/immunology
- Lung Neoplasms/pathology
- Lung Neoplasms/therapy
- Male
- Middle Aged
- Neoplasm Staging
- Prostatic Neoplasms/immunology
- Prostatic Neoplasms/pathology
- Prostatic Neoplasms/therapy
- RNA/analysis
- Receptors, Antigen, T-Cell, gamma-delta/genetics
- Receptors, Antigen, T-Cell, gamma-delta/metabolism
- T-Lymphocytes/metabolism
- T-Lymphocytes/pathology
- Zoledronic Acid
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Koivunen JP, Kim J, Lee J, Rogers AM, Park JO, Zhao X, Naoki K, Okamoto I, Nakagawa K, Yeap BY, Meyerson M, Wong KK, Richards WG, Sugarbaker DJ, Johnson BE, Jänne PA. Mutations in the LKB1 tumour suppressor are frequently detected in tumours from Caucasian but not Asian lung cancer patients. Br J Cancer 2008; 99:245-52. [PMID: 18594528 PMCID: PMC2480968 DOI: 10.1038/sj.bjc.6604469] [Citation(s) in RCA: 130] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Somatic mutations of LKB1 tumour suppressor gene have been detected in human cancers including non-small cell lung cancer (NSCLC). The relationship between LKB1 mutations and clinicopathological characteristics and other common oncogene mutations in NSCLC is inadequately described. In this study we evaluated tumour specimens from 310 patients with NSCLC including those with adenocarcinoma, adenosquamous carcinoma, and squamous cell carcinoma histologies. Tumours were obtained from patients of US (n=143) and Korean (n=167) origin and screened for LKB1, KRAS, BRAF, and EGFR mutations using RT—PCR-based SURVEYOR-WAVE method followed by Sanger sequencing. We detected mutations in the LKB1 gene in 34 tumours (11%). LKB1 mutation frequency was higher in NSCLC tumours of US origin (17%) compared with 5% in NSCLCs of Korean origin (P=0.001). They tended to occur more commonly in adenocarcinomas (13%) than in squamous cell carcinomas (5%) (P=0.066). LKB1 mutations associated with smoking history (P=0.007) and KRAS mutations (P=0.042) were almost mutually exclusive with EGFR mutations (P=0.002). The outcome of stages I and II NSCLC patients treated with surgery alone did not significantly differ based on LKB1 mutation status. Our study provides clinical and molecular characteristics of NSCLC, which harbour LKB1 mutations.
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Research Support, Non-U.S. Gov't |
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130 |
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Ambiru S, Miyazaki M, Ito H, Nakagawa K, Shimizu H, Yoshidome H, Shimizu Y, Nakajima N. Benefits and limits of hepatic resection for gastric metastases. Am J Surg 2001; 181:279-83. [PMID: 11376587 DOI: 10.1016/s0002-9610(01)00567-0] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The significance of hepatic resection for gastric metastases has been controversial. METHODS Forty consecutive patients undergoing hepatic resection for gastric metastases were reviewed to examine the benefits and the limits of hepatic resection using univariate and multivariate analyses. RESULTS The overall survival was 27% at 2 years, 18% at 5 years, and 11% at 10 years. Six patients survived more than 5 years. All of the 6 patients underwent anatomical hepatic resection more extensive than segmentectomy, with sufficient resection margin. There were recurrences in 31 patients, and 94% of the recurrences were in the remaining liver. Univariate analysis showed time of hepatic metastases (P = 0.0078) and resection margin (P = 0.024) as significant prognostic factors. Multivariate analysis indicated that only time of hepatic metastases was an independent prognostic factor that influenced survival. CONCLUSIONS These results suggest that in patients with synchronous metastases we should consider patient selection more strictly, and that in patients with metachronous metastases we should perform anatomical hepatic resection with sufficient resection margin.
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Katayama M, Hirai S, Kamihagi K, Nakagawa K, Yasumoto M, Kato I. Soluble E-cadherin fragments increased in circulation of cancer patients. Br J Cancer 1994; 69:580-5. [PMID: 8123491 PMCID: PMC1968869 DOI: 10.1038/bjc.1994.106] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Monoclonal antibodies were raised against human placental soluble E-cadherins and used in an immunoenzymometric assay to detect soluble E-cadherins in biological fluids. The E-cadherin assay was accurate enough to quantitate the concentration of soluble E-cadherin in the cell culture supernatants. Immunoreactive E-cadherins, identified as existing in the soluble form in normal serum, were shown to have apparent lower molecular mass (approximately 80 kDa) than intact molecules of E-cadherin. We found that the immunoreactive E-cadherin levels in the serum of the studied cancer patients were significantly elevated (mean +/- s.d. 3.80 +/- 2.36 micrograms ml-1, P < 0.0001) when compared with the normal levels (1.99 +/- 0.50 micrograms ml-1). We also found that serum E-cadherin levels in the 22 patients with gastric cancer (3.51 +/- 1.78 micrograms ml-1, P < 0.02) or the 11 patients with hepatocellular cancer (5.55 +/- 3.11 micrograms ml-1, P < 0.001) were significantly higher than those in the 26 diabetic patients (2.33 +/- 1.58 micrograms ml-1). Of the 54 cancer patients, 53.7% exhibited an elevated amount of soluble E-cadherin in serum. Thus, it is evident that soluble E-cadherin in circulation can be used as a prospective tumour marker that accurately reflects the progressive regeneration of E-cadherin at tumour sites, potentially induced by tumour-associated proteolytic degradation.
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Higashi Y, Sasaki S, Sasaki N, Nakagawa K, Ueda T, Yoshimizu A, Kurisu S, Matsuura H, Kajiyama G, Oshima T. Daily aerobic exercise improves reactive hyperemia in patients with essential hypertension. Hypertension 1999; 33:591-7. [PMID: 9931171 DOI: 10.1161/01.hyp.33.1.591] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effects of long-term aerobic exercise on endothelial function in patients with essential hypertension remain unclear. To determine whether endothelial function relating to forearm hemodynamics in these patients differs from normotensive subjects and whether endothelial function can be modified by continued physical exercise, we randomized patients with essential hypertension into a group that engaged in 30 minutes of brisk walking 5 to 7 times weekly for 12 weeks (n=20) or a group that underwent no activity modifications (control group, n=7). Forearm blood flow was measured using strain-gauge plethysmography during reactive hyperemia to test for endothelium-dependent vasodilation and after sublingual nitroglycerin administration to test endothelium-independent vasodilation. Forearm blood flow in hypertensive patients during reactive hyperemia was significantly less than that in normotensive subjects (n=17). Increases in forearm blood flow after nitroglycerin were similar between hypertensive and normotensive subjects. Exercise lowered mean blood pressure from 115.7+/-5.3 to 110.2+/-5.1 mm Hg (P<0.01) and forearm vascular resistance from 25.6+/-3.2 to 23. 2+/-2.8 mm Hg/mL per minute per 100 mL tissue (P<0.01); no change occurred in controls. Basal forearm blood flow, body weight, and heart rate did not differ with exercise. After 12 weeks of exercise, maximal forearm blood flow response during reactive hyperemia increased significantly, from 38.4+/-4.6 to 47.1+/-4.9 mL/min per 100 mL tissue (P<0.05); this increase was not seen in controls. Changes in forearm blood flow after sublingual nitroglycerin administration were similar before and after 12 weeks of exercise. Intra-arterial infusion of the nitric oxide synthase inhibitor NG-monomethyl-L-arginine abolished the enhancement of reactive hyperemia induced by 12 weeks of exercise. These findings suggest that through increased release of nitric oxide, continued physical exercise alleviates impairment of reactive hyperemia in patients with essential hypertension.
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Clinical Trial |
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Yokokawa K, Tahara H, Kohno M, Murakawa K, Yasunari K, Nakagawa K, Hamada T, Otani S, Yanagisawa M, Takeda T. Hypertension associated with endothelin-secreting malignant hemangioendothelioma. Ann Intern Med 1991; 114:213-5. [PMID: 1984746 DOI: 10.7326/0003-4819-114-3-213] [Citation(s) in RCA: 122] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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Case Reports |
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122 |
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Nakagawa K, Miyazawa T. Chemiluminescence-high-performance liquid chromatographic determination of tea catechin, (-)-epigallocatechin 3-gallate, at picomole levels in rat and human plasma. Anal Biochem 1997; 248:41-9. [PMID: 9177723 DOI: 10.1006/abio.1997.2098] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A method of chemiluminescence detection-high-performance liquid chromatography (CL-HPLC) for the highly specific determination of tea catechin, (-)-epigallocatechin 3-gallate (EGCg), present in rat and human plasma has been newly developed. The CL-HPLC system consists of reversed-phase HPLC and chemiluminescence detector, in which separated EGCg generates chemiluminescence at post column successively reacting with the following two chemiluminescence cocktails; 8.2 M acetaldehyde in 50 mM phosphate buffer (pH 7.4, contained 108 mg horseradish peroxidase/L) and 8.8 M hydrogen peroxide aqueous solution. The plasma EGCg was extracted by methanol. This method enables the detection of EGCg in the free form selectively at as low as 2 pmol with recovery of 84%. The EGCg concentration in fasted rat plasma was initially below the detection limit (< 2 pmol/ml), but increased to maximum level (2284 pmol/ml plasma, 1047 ng/ml; calculated 0.012% of ingested EGCg) 30 min after a single oral supplementation of 56 mg EGCg per rat. The EGCg concentration in fasted human plasma was also initially below the detection limit and increased to 341 pmol/ml (156 ng/ml; calculated 0.32% of ingested EGCg) at 60 min after a single oral intake of 97 mg EGCg per subject. The results indicated that tea catechin, EGCg, is absorbed from the digestive tract into the rat and human body and that the CL-HPLC method reported here should be a powerful tool for studying the metabolic fate and bioavailability of EGCg.
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