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1.
Summary Experimental data suggest that multidrug resistance in cancer may be overcome by using an increased dose of anticancer agent(s) in combination with a resistance-modifying agent (RMA). We studied the pharmacokinetics and metabolism of both epirubicin (EPI) and verapamil (VPL) to explore the possible pharmacokinetic interactions between these two drugs. Ten patients with advanced breast cancer were given EPI (40 mg/m2 in a daily i.v. bolus for 3 consecutive days), and five of them also received VPL (4×120 mg/daily p.o. for 4 consecutive days). The data indicated a significant interaction between these two drugs that affected their metabolism. The areas under the concentration-time curves (AUC) obtained for epirubicin glucuronide, epirubicinol glucuronide, and both of the 7-deoxy-aglycones were higher in the EPI+VPL group as compared with the EPI group. The AUC, terminal half-life, mean residence time, volume of distribution at steady state, and plasma clearance of EPI alone as compared with EPI+VPL did not differ significantly. These results suggest either an induction of enzymes necessary for drug metabolism or an increase in the liver blood flow, resulting in an enhanced generation of metabolites with time or in an inhibition of excretion processes. Comparisons of the AUC values obtained for EPI and its metabolites after the first, second, and third injections of EPI revealed a cumulative effect for the metabolites that was more pronounced in the EPI+VPL group, being significant (P<0.05) for epirubicin glucuronide in both treatment groups and for epirubicinol glucuronide in the EPI+VPL group. Maximal concentrations of VPL and nor-VPL reached 705±473 and 308±122 ng/ml, respectively, with the steady-state concentrations being 265±42 ng/ml for VPL and 180±12 ng/ml for nor-VPL.This study was supported by the Erich und Gertrud Roggenbuck-Stiftung zur Förderung der Krebsforschung (Hamburg). The anthracycline metabolites were kindly provided by Dr. A. Suarato (Farmitalia, Milano, Italy); nor verapamil was provided by Dr. Traugott (Knoll, Ludwigshafen, Germany) 相似文献
2.
Addition of bevacizumab to bolus fluorouracil and leucovorin in first-line metastatic colorectal cancer: results of a randomized phase II trial. 总被引:11,自引:0,他引:11
Fairooz F Kabbinavar Joseph Schulz Michael McCleod Taral Patel John T Hamm J Randolph Hecht Robert Mass Brent Perrou Betty Nelson William F Novotny 《Journal of clinical oncology》2005,23(16):3697-3705
PURPOSE: Bevacizumab, a monoclonal antibody against vascular endothelial growth factor, increases survival when combined with irinotecan-based chemotherapy in first-line treatment of metastatic colorectal cancer (CRC). This randomized, phase II trial compared bevacizumab plus fluorouracil and leucovorin (FU/LV) versus placebo plus FU/LV as first-line therapy in patients considered nonoptimal candidates for first-line irinotecan. PATIENTS AND METHODS: Patients had metastatic CRC and one of the following characteristics: age > or = 65 years, Eastern Cooperative Oncology Group performance status 1 or 2, serum albumin < or = 3.5 g/dL, or prior abdominal/pelvic radiotherapy. Patients were randomly assigned to FU/LV/placebo (n = 105) or FU/LV/bevacizumab (n = 104). The primary end point was overall survival. Secondary end points were progression-free survival, response rate, response duration, and quality of life. Safety was also assessed. RESULTS: Median survival was 16.6 months for the FU/LV/bevacizumab group and 12.9 months for the FU/LV/placebo group (hazard ratio, 0.79; P = .16). Median progression-free survival was 9.2 months (FU/LV/bevacizumab) and 5.5 months (FU/LV/placebo); hazard ratio was 0.50; P = .0002. Response rates were 26.0% (FU/LV/bevacizumab) and 15.2% (FU/LV/placebo) (P = .055); duration of response was 9.2 months (FU/LV/bevacizumab) and 6.8 months (FU/LV/placebo); hazard ratio was 0.42; P = .088. Grade 3 hypertension was more common with bevacizumab treatment (16% v 3%) but was controlled with oral medication and did not cause study drug discontinuation. CONCLUSION: Addition of bevacizumab to FU/LV as first-line therapy in CRC patients who were not considered optimal candidates for first-line irinotecan treatment provided clinically significant patient benefit, including statistically significant improvement in progression-free survival. 相似文献
3.
Sabrina Benedetto Roberta Pulito Simonetta Geninatti Crich Guido Tarone Silvio Aime Lorenzo Silengo Jrg Hamm 《Magnetic resonance in medicine》2006,56(4):711-716
Targeted imaging requires site-specific accumulation of a contrast agent (CA), and the properties of that agent must be selected according to the abundance of the target to obtain a signal above the detection limit of the instrument. However, numerical estimates of receptors per cell are rarely found in the literature. Integrin receptors would be particularly promising targets because of their accessibility from the blood stream and expression on activated neovascular endothelial cells. We systematically estimated the number of integrin receptors of cell lines and primary cells by flow cytometry analysis. Since integrin receptors are heterodimeric molecules, and alpha(v) forms complexes with various beta subunits, the numbers of alpha(v) and beta(3) subunits are therefore dissimilar. The observed values are 3 . 10(3)-1.4 . 10(4)/cell for alpha(v), and 5.3 . 10(2)-1.1 . 10(4)/cell for beta(3). Despite the low number of exposed receptors, we show that up to single-cell MR visualization can be achieved with the use of iron oxide beads complexed with antibodies as CAs. 相似文献
4.
MRI is estabished as a modality available for use in the diagnosis of cervical cancer. The soft tissue contrast it supplies is far better than that of any other method, making it the modality of choice for direct visualization of the carcinoma and thus also for tumor staging. Pelvic MRI performed as part of the pretreatment evaluation has been shown to be cost effective, and it is recommended for use in macroscopic cervical cancer in the guidelines of professional societies for gynecologists and oncologists. It has proved to be a reliable method for the early detection of recurrent tumors. It remains unsurpassed for accurate visualization of local tumor extent and involvement of adjacent pelvic organs in recurrent cervical cancer. It is also the method of choice for use in the planning of brachytherapy. With the increasing use of PET and PET/CT for investigations in oncology patients a second method has emerged. This seems to have advantages particularly in the detection of lymph node metastases by whole-body examination. Encouraging results on detection of recurrent cervical cancer during follow-up treatment by PET/CT have also been published, but a definitive assessment of the value of PET in tumor aftertreatment cannot be reached without more comparative studies against MRI. Moreover, there have so far been no studies evaluating the cost effectiveness of PET. In the near future it will be necessary to reconsider the new diagnostic modalities with reference to their accuracy in staging, since therapy is oriented increasingly to disease stage and increasingly specific treatment methods are applied. 相似文献
5.
Matthias Bollow Wolfgang Knauf Agnieszka Korfel Matthias Taupitz Andreas Schilling Karl-Jürgen Wolf Bernd Hamm 《Journal of magnetic resonance imaging : JMRI》1997,7(1):241-250
The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio. 相似文献
6.
Normal morphology of sacroiliac joints in children: magnetic resonance studies related to age and sex 总被引:2,自引:0,他引:2
M. Bollow J. Braun J. Kannenberg T. Biedermann C. Schauer-Petrowskaja S. Paris S. Mutze B. Hamm 《Skeletal radiology》1997,26(12):697-704
Objective. To determine in a prospective study the normal MRI morphology of the sacroiliac joints (SIJs) in relation to age and sex
during adolescence. Design and patients. A total of 98 children (63 boys, mean age 12.7±2.8 years; 35 girls, mean age 13.7±2.3 years), ranging in age from 8 to 17
years, with juvenile chronic arthritis (JCA) but without signs of sacroiliitis fulfilled the study prerequisites (no back
pain and no pathologic changes of the SIJs on physical examination before MRI in a 1.5-year follow-up). An additional eight
HLA-B27-negative boys and eight HLA-B27-negative girls without arthritis served as controls. The MRI protocol comprised a
T1-weighted SE sequence, an opposed-phase T2*-weighted GE sequence, and a dynamic contrast-enhanced study in single-section
technique. Results. Noncontrast MRI permitted differentiation of “open” from ossified segmental and lateral apophyses of the sacral wings, with
a significant difference in age (P <0.05) between children with open and ossified apophyses. Ossification of the apophyses of the sacral wings was seen significantly
earlier (P <0.05) in girls than in boys. Girls also had a significantly higher incidence of transitional lumbosacral vertebrae, pelvic
asymmetries, and accessory joints. In the contrast-enhanced opposed-phase MRI study, normal cartilage of the SIJs showed no
contrast enhancement whereas the joint capsule showed a moderate enhancement. Conclusion. There are significant age- and sex-related differences in the normal MRI morphology of juvenile SIJs. Our findings might
serve as a standard of comparison for the evaluation of pathologic changes – in particular for the early identification of
juvenile sacroiliitis. 相似文献
7.
C W Hamm J H Robertson J T Robertson D K Hathaway E Tolley 《The Journal of neuroscience nursing》1988,20(5):303-308
Cardiovascular changes have been noted to occur during movement from the operating room or recovery room (RR) to the intensive care unit (ICU). This study examined blood pressure changes and related variables during transport from the RR to the ICU in 135 postoperative acoustic tumor patients. Although there was no significant change in blood pressure values from the RR to the ICU, patients with pre-existing hypertension and elevated RR blood pressures were noted to have an increased frequency of postoperative complications. In addition, a relationship was noted between administration of halothane and frequency of postoperative complications. Results highlight the need for nurses not only to monitor, but also closely control postoperative blood pressure in this population. 相似文献
8.
A cytoskeletal actin gene in the mosquito Anopheles gambiae 总被引:2,自引:0,他引:2
C. E. Salazar D. Mills Hamm D. M. Wesson C. B. Beard V. Kumar F. H. Collins 《Insect molecular biology》1994,3(1):1-13
Five actin genes have been identified in the mosquito Anopheles gambiae , and a constitutively expressed actin gene has been chosen for detailed analysis. We have physically mapped and sequenced this gene and six associated cDNAs, including translated coding regions, as well as the 5 and 3 flanking sequences. Analysis of stage-specific RNA shows this gene to be present in all stages of mosquito development and in an established A. gambiae cell line, thus indicating a cytoskeietal actin. In the sequence of the translated coding region and in pattern of expression, this gene is very similar to the cytoskeietal actin genes of Droso-phila melanogaster , and in sequence, equally similar to the Artemia cytoskeietal actin gene 403 (99.2% identity among the three amino acid sequences). Sequencing of this A. gambiae actin gene (designated actWior its location in chromosome division 1D) and selected cDNAs shows that it possesses three alternative leader sequences; thus the gene appears to have three alternative promoters. These promoters should ultimately prove useful in the production of transgenic constructs for constitutive expression. 相似文献
9.
Barbara Schubert Cornelia S. Seitz Eva‐Bettina Brcker Henning Hamm 《Journal der Deutschen Dermatologischen Gesellschaft》2007,5(8):680-682
Childhood psoriasis is a disease with manifold clinical presentations which can make the correct diagnosis sometimes difficult. In a female infant, slightly itching, erythematous papules and plaques with discrete scaling spread over large parts of the integument starting from age three months. Histological examination supported the diagnosis of exanthematous infantile psoriasis. Topical treatment with dithranol in petrolatum led to slow clearance of the skin lesions. 相似文献
10.
A 72-year-old man with increasing shortness of breath and atypicalangina pectoris received a chest radiograph 相似文献