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61.
Multiple-dose pharmacokinetics of epirubicin at four different dose levels: studies in patients with metastatic breast cancer 总被引:2,自引:0,他引:2
Preben Jakobsen Eva Steiness Lars Bastholt Mads Dalmark Anders Lorenzen Dorthe Petersen Susanne B. Gjedde Erik Sandberg Carsten Rose Ole S. Nielsen Henning T. Mouridsen Anders Jakobsen 《Cancer chemotherapy and pharmacology》1991,28(1):63-68
Summary Pharmacokinetic analysis of epirubicin and its metabolites epirubicinol and 7-deoxy-13-dihydro-epirubicinol aglycone during the first and the fourth courses of treatment was performed in 78 patients with metastatic breast cancer. The patients were treated every 3 weeks with epirubicin given as 10-min i.v. infusions at four different dose levels: 40, 60, 90 and 135 mg/m2. In most cases (76 of 78 cases), plasma concentration-time curves fitted to a three-compartmental pharmacokinetic model. The terminal half-life of epirubicin was independent of dose and duration of treatment. Large interindividual differences were demonstrated (meant
1/2, 21.6±7.9 h; range, 10.6–69 h;n=110). In two subjects, extremely long half-lives and high serum bilirubin concentrations indicated impaired liver function. No correlation was found between the half-life and levels of liver alanine aminotransferase (ALAT) or serum creatinine. The metabolite epirubicinol appeared quickly after epirubicin administration and its half-lives were shorter than that of the parent compound (meant
1/2, 18.1±4.8 h; range, 8.2–38.4 h;n=105).Formation of the aglycone metabolite was delayed and the half-life of this metabolite was shorter than that of epirubicin (meant
1/2, 13±4.6 h; range, 2.7–29 h;n=104). The AUC of epirubicin and the total AUC (drug and metabolites) were linearly proportional to the dose, with the former value constituting two-thirds of the latter. A correlation was found between AUC and the plasma concentration of epirubicin at two time points (2 and 24 h after administration). The proposed model was AUC=9.44×c
2+62.5×c
24+157.7 (r=0.953).This work was supported by the Lundbeck Foundation, the Michaelsen Foundation and Farmitalia Carlo Erba Ltd. 相似文献
62.
Steady-state kinetics of imipramine in patients 总被引:1,自引:0,他引:1
Lars F. Gram Ib Søndergaard Johannes Christiansen Gorm Odden Petersen Per Bech Niels Reisby Ilse Ibsen Jørgen Ortmann Adam Nagy Sven J. Dencker Ove Jacobsen Ole Krautwald 《Psychopharmacology》1977,54(3):255-261
Steady-state plasma level kinetics were studied in 76 patients given imipramine (IP) 150 to 225 mg/day for 2–5 weeks. IP was given in three divided doses at 8.00 a.m., 1.00 p.m. and 5.00 p.m. Plasma concentrations of IP and its active metabolite desipramine (DMI) were determined by quantitative in situ thin-layer chromatography. The plasma levels of IP and DMI showed pronounced flucutations throughout the day with a ratio of about 2 between highest and lowest level. Patients with steady-state levels of IP and/or DMI below 50 g/l reached this within 1 week of treatment. Patients with higher steady-state levels reached steady-state concentrations within 2–3 weeks. There were some intraindividual fluctuations in plasma levels from week to week after steady state had been reached (coefficient of variation: 10–20%). Interindividually, the steady-state levels corrected to a dose of 3.5 mg/kg per day varied considerably: IP: 6–356 g/l, DMI: 24–659 g/l and IP+DMI: 58–809 g/l. The steady-state plasma levels showed a skew distribution that became normal by logarithmic transformation. The IP/DMI ratio ranged from 0.07 to 5.5 with a median value of 0.47. Compared to data from amitriptyline treated patients the IP/DMI ratios had significantly lower median value and larger variation than the corresponding plasma level ratios of amitriptyline/nortriptyline. Several statistically significant differences in steady-state levels between age groups were found. For IP: Women aged 30–39 had lower levels than women aged 20–29, 40–49, and 50–59, and men aged 50–59 and 60–65; men aged 30–39 had lower levels than men aged 60–65. For DMI: Women aged 30–39 had lower levels than women aged 50–59. 相似文献
63.
Screening for Early Colorectal Cancer 总被引:2,自引:0,他引:2
Kronborg O 《World journal of surgery》2000,24(9):1069-1074
There is now solid evidence from randomized trials suggesting that it is possible to reduce mortality from colorectal cancer by 15% to 25% by screening with fecal occult blood tests (FOBTs). The major benefit results from detection of early cancer in average-risk persons above 50 years of age who have a positive test followed by colonoscopy. However, it has to be demonstrated that the same acceptability can be reached in the general population as that obtained in trials. Many countries must establish a screening organization in a limited area to learn how satisfactory quality assurance can be obtained before a country-wide screening program is set up. So far, screening has not resulted in a reduced incidence of colorectal cancer in true population studies despite removal of two to three times as many possible precursors compared to controls. Cost-effectiveness will probably be as good as that known from screening for breast cancer with mammography and better than that for cervical cancer. However, the calculations are based on the unhydrated Hemoccult-II test in randomized trials. More sensitive methods would be attractive, but none has yet been evaluated properly in average-risk persons. There is no general agreement how to screen high risk groups such as patients with previous colorectal adenomas and carcinomas, one or two first-degree relatives with colorectal neoplasia, or ulcerative colitis. Families with familial adenomatous polyposis or hereditary nonpolyposis colorectal cancer, however, are presented with firm guidelines. Genetic screening has been helpful in no more than these two small groups in the colorectal carcinoma universe. 相似文献
64.
Dr Ole S. Nielsen Jean-Yves Blay Ian R. Judson Martine van Glabbeke Jaap Verweij Allan T. van Oosterom 《American Journal of Cancer》2003,2(3):211-221
In the present paper the treatment of advanced and metastatic soft tissue sarcoma is reviewed with the primary emphasis on chemotherapy. One of the major advances in the treatment of soft tissue sarcomas is their treatment by multidisciplinary teams in specialized centers. Despite optimal local treatment of the primary tumor, disseminated disease will develop in many patients. Consequently, chemotherapy has been extensively studied but, unfortunately, the responsiveness of these tumors to chemotherapy has been disappointingly low. Doxorubicin and ifosfamide appear to be the most effective drugs — the latter with a somewhat higher toxicity at effective dosages. Other drugs with some first line activity are dacarbazine, liposomal doxorubicin and possibly trabectedin (ET-743). Imatinib is very effective in gastrointestinal stromal tumors (GIST) where it is now the treatment of choice. The combination of doxorubicin and ifosfamide increases the response rate without affecting overall survival. For these reasons, single agent doxorubicin is, in many centers, considered the standard treatment for advanced soft tissue sarcoma, and combination chemotherapy should be reserved for special subgroups of patients such as young patients with chemosensitive tumors. Chemotherapy for patients with advanced and metastatic soft tissue sarcoma is inadequate at present and new drugs are desperately needed. Fortunately, exciting new drugs are under development and hopefully they will improve the treatment of patients with this disease. 相似文献
65.
PURPOSE: Recent experimental work indicates a major role for PTEN and p27 in prostate cancer. The combined loss of PTEN and p27 was found to strongly increase the development of prostatic carcinomas in an animal model, and a prognostic value in human tumors was postulated. The purpose of our study was to examine the impact of PTEN and p27 on prognosis in a series of prostate cancer patients, using high-density tissue microarray technology for expression profile analysis of PTEN, p27, and tumor cell proliferation. EXPERIMENTAL DESIGN: The expression of PTEN and p27 was examined in primary prostatic carcinomas from 104 patients treated with radical prostatectomy and with complete follow-up available. Using high-throughput tissue microarrays, the expression of PTEN and p27 was examined by immunohistochemistry, and the results were related to clinicopathological variables, tumor cell proliferation (Ki-67), and time to disease progression. RESULTS: PTEN was negative in 28 of 103 tumors (27.2%), and median p27 expression was 64%. Combined loss of PTEN and p27 expression defined a group of 18 tumors (17.5%) associated with increased tumor diameter, seminal vesicle invasion, increased pathological stage, and elevated tumor cell proliferation by Ki-67. Cox regression analysis revealed that loss of PTEN/p27 expression and histological grade were both independent predictors of time to biochemical failure and clinical recurrence. CONCLUSIONS: Our findings strongly support the importance of PTEN and p27 for the progression of human prostate cancer because loss of PTEN/p27 expression was associated with adverse pathological parameters, tumor cell proliferation, and increased risk of recurrence. 相似文献
66.
Claudia Sch?llkopf Karin Ekstr?m Smedby Henrik Hjalgrim Klaus Rostgaard Ole Gadeberg G?ran Roos Anna Porwit-Macdonald Bengt Glimelius Hans-Olov Adami Mads Melbye 《Cancer epidemiology, biomarkers & prevention》2005,14(7):1791-1796
BACKGROUND: Epidemiologic evidence of an association between tobacco smoking and non-Hodgkin's lymphoma has been conflicting. This may reflect that non-Hodgkin's lymphoma comprises several distinct disease entities with different etiologies, as some studies have indicated an association between smoking and follicular lymphoma. OBJECTIVE: To investigate the association between cigarette smoking and non-Hodgkin's lymphoma risk, overall and by subtype. METHODS: As part of a nationwide Danish-Swedish population-based case-control study, we interviewed 3,055 incident non-Hodgkin's lymphoma patients and 3,187 population controls. All lymphomas were uniformly classified according to the WHO classification. We used unconditional logistic regression to estimate adjusted odds ratios (OR) and 95% confidence intervals (95% CI) for the association between cigarette smoking and risk of non-Hodgkin's lymphoma. RESULTS: Cigarette smoking was not associated with the risk of non-Hodgkin's lymphoma overall (OR, 0.97; 95% CI, 0.87-1.08) nor with the major subgroups such as diffuse large B-cell lymphoma (OR, 0.94; 95% CI, 0.79-1.10), chronic lymphocytic leukemia (OR, 0.86; 95% CI, 0.72-1.02), or follicular lymphoma (OR, 1.03; 95% CI, 0.85-1.24). Female smokers were at a marginally increased risk of follicular lymphoma (OR, 1.41; 95% CI, 1.04-1.92). Men who had ever smoked had a significantly increased risk of T-cell lymphoma (OR, 1.67; 95% CI, 1.11-2.51). No dose-response association with cigarette smoking could be established for any lymphoma subgroup. CONCLUSION: We found little evidence of an association between cigarette smoking and non-Hodgkin's lymphoma risk overall. Although increased risks of follicular lymphoma in female smokers and of T-cell lymphoma in male smokers were suggested, no dose-response relationship was observed, leaving limited support for causality. 相似文献
67.
68.
Tadeusz Włostowski Paweł Kozłowski Barbara Łaszkiewicz-Tiszczenko Ewa Oleńska Olgierd Aleksandrowicz 《Bulletin of environmental contamination and toxicology》2014,93(5):526-531
The objectives of this study were (1) to determine cadmium (Cd) accumulation in the midgut gland of a land snail Helix pomatia L. inhabiting residential areas of the 14 largest cities in Poland, and (2) to examine whether the accumulated Cd exerted any toxic effects. The average accumulation of Cd in the midgut gland of snails, weighing 16–18 g, ranged from 7.00 to 87.3 µg/g dry weight (0.06–0.77 µmol/g) and differed significantly among animals from the various urban areas. This difference in Cd accumulation was not related to city population, but was associated with the topsoil Cd (R2 = 0.868, p < 0.0001). The tissue Cd was not found to produce toxicity (histopathology, programmed cell death, lipofuscin formation or lipid peroxidation), probably due to the induction of sufficiently high quantities of metallothionein and glutathione, well-known protective molecules. 相似文献
69.
70.