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71.
Summary The dose response curves of doxorubicin for hematopoietic rat bone marrow cells were investigated and compared with the dose-response curves of doxorubicin for leukemia cells from bone marrow and spleen of rats inoculated with an acute myelocytic leukemia (BNML). Various assays were used to determine the cytotoxicity of doxorubicin. It was found that the inhibition of DNA synthesis by doxorubicin compared well with results obtained with in vivo assays for the determination of clonogenic hematopoietic (CFU-S) and leukemic (LCFU-S) cells. It was found that doxorubicin at concentrations ranging from 0.1–1.0 g · 10-7 cells inhibits DNA synthesis of leukemic cells to 60% and that of hematopoietic cells to 90%. Higher doxorubicin concentrations further inhibit DNA synthesis of only hematopoietic cells. These results were confirmed with clonogenic assays. Pre-treatment with the S phase-specific drug arabinoside cytosine (ara-C) increased the efficacy of doxorubicin in vitro significantly. In view of the doxorubicin concentrations in bone marrow obtained in vivo (1 g · 10-7 cells), it is concluded that dosage reduction may reduce toxicity with no concomitant decrease of antileukemic activity of doxorubicin. 相似文献
72.
Carla M van Herpen Maaike Looman Marijke Zonneveld Nicole Scharenborg Peter C de Wilde Louis van de Locht Matthias A W Merkx Gosse J Adema Pieter H de Mulder 《Clinical cancer research》2004,10(8):2626-2635
The objective of this Phase II study was to evaluate the pharmacodynamic and immune effects of intratumorally administered recombinant human interleukin-12 (IL-12) on regional lymph nodes, primary tumor, and peripheral blood. Ten previously untreated patients with head and neck squamous cell carcinoma were injected in the primary tumor two to three times, once/week, at two dose levels of 100 or 300 ng/kg, before surgery. We compared these patients with 20 control (non-IL-12-treated) patients. Toxicity was high, with unexpected dose-limiting toxicities at the 300 ng/kg dose level. Dose-dependent plasma IFN-gamma and IL-10 increments were detected. These cytokine levels were higher after the first injection than after the subsequent injections. A rapid, transient reduction in lymphocytes, monocytes, and all lymphocyte subsets, especially natural killer cells, was observed, due to a redistribution to the lymph nodes. In the enlarged lymph nodes of the IL-12-treated patients, a higher percentage of natural killer cells and a lower percentage of T-helper cells were found compared with control patients. The same pattern was detected in the infiltrate in the primary tumor. Real-time semiquantitative PCR analysis of peripheral blood mononuclear cells in the peripheral blood showed a transient decrease of T-bet mRNA. Interestingly, the peripheral blood mononuclear cells in the lymph nodes showed a 128-fold (mean) increase of IFN-gamma mRNA. A switch from the Th2 to a Th1 profile in the lymph nodes compared with the peripheral blood occurred in the IL-12-treated patients. In conclusion, in previously untreated head and neck squamous cell carcinoma patients, recombinant human IL-12 intratumorally showed dose-limiting toxicities at the dose level of 300 ng/kg and resulted in measurable immunological responses locoregionally at both dose levels. 相似文献
73.
O Reerink N H Mulder G Botke W J Sluiter B G Szabó J T M Plukker R C J Verschueren G A P Hospers 《European journal of surgical oncology》2004,30(9):954-958
PURPOSE: Assessment of the results and prognostic factors in patients with locally recurrent rectal cancer treated with curative intent. PATIENTS AND METHODS: Forty patients with an isolated pelvic recurrence of rectal cancer were studied retrospectively. The treatment consisted of radiotherapy alone or combined with chemotherapy and/or surgery performed between January 1992 and July 2001. Radiotherapy was given with a 3-4 fields technique (6-15 MV), five times a week. The median radiation dose was 50 Gy (range 25-66.6 Gy). Twenty-five patients underwent salvage surgery. Five patients were treated with concomitant chemotherapy (5-fluoro-uracil/leucovorin) (5FU/LV) during the 1st and 5th week of radiotherapy. RESULTS: Twenty-two of the 40 patients were male. The local recurrence free survival after 3 and 5 years, respectively, was 49 and 39%. Male gender was the only independent factor associated with failure of local control. The 3 and 5-year overall survival of the total group was 36 and 19%, respectively, with a median survival of 26 months. CONCLUSION: In a selection of patients in the treatment of locally recurrent rectal cancer valuable local palliation if not cure, can be reached. A multimodality approach seems to offer the best chances in this threatening situation. 相似文献
74.
Kanhai RC Hage JJ van Diest PJ Bloemena E Mulder JW 《The American journal of surgical pathology》2000,24(1):74-80
The histologic changes induced in the mammary gland of male-to-female transsexuals have not yet been reported in the literature. We studied the histologic changes induced by chemical and surgical castration and estrogen therapy in the breasts of 14 such patients, with particular reference to acinar and lobular formation. To objectify the influence of cross-sex treatment, the histologic findings were compared with those in two men treated hormonally for prostate cancer. The slight increase in the plasma estrogen-to-androgen ratio seen in idiopathic gynecomastia usually does not induce acinar and lobular formation in the male breast. In men treated with nonprogestative antiandrogens for prostate cancer, only moderate acinar and lobular formation occurs. Only in male-to-female transsexuals in whom progestative chemical castration is combined with feminizing estrogen therapy will full acinar and lobular formation occur with hormonally stimulated nuclei and pseudolactational changes. Hence, combined progestative antiandrogens and estrogens are necessary for genetically male breast tissue to mimic the natural histology of the female breast. Orchidectomy does not contribute to this. Apocrine metaplasia may occur in breasts of male-to-female transsexuals, but so far, only four cases of breast cancer in male-to-female transsexuals have been documented. 相似文献
75.
Urinary excretion of glutathione S transferases alpha and pi in patients with proteinuria: reflection of the site of tubular injury 总被引:3,自引:0,他引:3
In patients with renal diseases, proteinuria is a major determinant of progressive renal failure, probably by causing tubular cell injury. Little is known on extent and site of tubular cell injury in patients with proteinuria. Glutathione S transferases (GST) are cytosolic enzymes. The alpha isoform is present only in proximal tubular cells, whereas the pi isoform is confined to distal tubular cells. We have studied the urinary excretion of both isoenzymes in 56 (38 male and 18 female) patients with glomerular diseases and proteinuria. The mean age was 45 +/- (SD) 16 years, the median creatinine clearance was 80 (range 27-159) ml/min, and the median albuminuria was 4.2 (range 0.7-16.9) g/10 mmol creatinine. The excretions of both GST alpha (median 35.9 ng/10 mmol creatinine) and GST pi (median 24.8 ng/10 mmol creatinine) were elevated as compared with control values (upper limits 10 and 12 ng/10 mmol creatinine, respectively). The urinary excretion of GST pi, but not that of GST alpha, was inversely correlated with the creatinine clearance. The highest levels of GST alpha were found in patients with a well-preserved renal function, whereas highest levels of GST pi were found in patients with renal failure. In a small number of patients we performed immunofluorescent studies of renal tissue. An increased urinary excretion of GST alpha correlated with brush border damage and decreased staining of proximal tubules for that isoenzyme. Our data suggest that in patients with proteinuria initial injury is apparent at the proximal tubules. Measurements of GST alpha and GST pi appear useful to study longitudinal timing and site of proteinuria-induced tubular cell injury. 相似文献
76.
VS Khoo KH Liew EC Crennan IM D'Costa G Quong 《Journal of Medical Imaging and Radiation Oncology》1998,42(1):52-57
Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated. 相似文献
77.
Advanced or basic life support for trauma: meta-analysis and critical review of the literature 总被引:9,自引:0,他引:9
BACKGROUND: The question of whether to use advanced life support (ALS) or basic life support (BLS) for trauma patients in the prehospital setting has been much debated and still lacks a clear answer. The purpose of this study was to conduct a comprehensive critical review of the literature regarding this controversy METHODS: A total of 174 articles on prehospital ALS or BLS for trauma were reviewed. Fifteen of these studies were found to involve mortality statistics for both ALS- and BLS-treated patients. Odds ratios were calculated for survival in ALS versus BLS and summarized across studies on the basis of multivariate scoring systems that incorporated both design and methodological assessment. Overall odds ratios for all studies were calculated on the basis of both raw data from the papers, and weighted odds ratios were calculated from the scoring systems. RESULTS: Six studies were scored as being methodologically average (5 favoring BLS and 1 favoring ALS), two were scored as good (1 favoring BLS and 1 favoring ALS), seven as excellent (6 favoring BLS and 1 favoring ALS). Ten studies had an average study design score (6 favoring BLS and 4 favoring ALS) and seven had a good study design score (6 favoring BLS and 1 favoring ALS). Weighted odds ratio for dying was 2.59 for patients receiving ALS compared with those receiving BLS. The crude odds ratio was 2.92. CONCLUSION: The aggregated data in the literature have failed to demonstrate a benefit for on-site ALS provided to trauma patients and support the scoop and run approach. 相似文献
78.
De Hert SG Vander Linden PJ ten Broecke PW De Mulder PA Rodrigus IE Adriaensen HF 《Anesthesiology》2000,93(2):374-381
BACKGROUND: In a subset of coronary surgery patients, a transient increase in cardiac load by leg elevation resulted in a decrease in maximal rate of pressure development (dP/dtmax) and a major increase in end-diastolic pressure (EDP). This impairment of left ventricular (LV) function appeared to be related to a deficient length-dependent regulation of myocardial function. The present study investigated whether analysis of transmitral flow patterns with transesophageal echocardiography constituted a noninvasive method to identify these patients. METHODS: High-fidelity LV pressure tracings and transmitral flow signals were obtained in 50 coronary surgery patients during an increase in cardiac load by leg elevation. Using linear regression analysis, changes in transmitral E-wave velocity and deceleration time (DT) were related to changes in dP/dtmax and EDP. RESULTS: Changes in dP/dtmax with leg elevation were closely related to corresponding changes in E-wave velocity (r = 0.81; P < 0. 001) and to changes in DT (r = 0.78; P < 0.001). Similarly, changes in EDP were related to changes in E-wave velocity (r = 0.83; P < 0. 001) and to changes in DT (r = 0.84; P < 0.001). The decrease in dP/dtmax and the major increase in EDP in some patients was associated with an increase in E-wave velocity and a decrease in DT, indicating development of a restrictive LV filling pattern. CONCLUSIONS: Impairment of LV function with leg elevation was associated with the development of a restrictive transmitral filling pattern. Analysis of transmitral flow patterns by means of transesophageal echocardiography therefore allowed noninvasive identification of a subset of coronary surgery patients with impaired length-dependent regulation of LV function. 相似文献
79.
Adrienne H Brouwers Peter F A Mulders Pieter H M de Mulder Wim J M van den Broek Wilhelmina C A M Buijs Carola Mala Frank B M Joosten Egbert Oosterwijk Otto C Boerman Frans H M Corstens Wim J G Oyen 《Journal of clinical oncology》2005,23(27):6540-6548
PURPOSE: A previous activity dose-escalation study using 131I-labeled chimeric monoclonal antibody cG250 in patients with progressive metastatic renal cell carcinoma (RCC) resulted in occasional therapeutic responses. The present study was designed to determine the safety and therapeutic efficacy of two sequential high-dose treatments with 131I-cG250. PATIENTS AND METHODS: Patients (n = 29) with progressive metastatic RCC received a low dose of (131)I-cG250 for assessment of preferential targeting of metastatic lesions, followed by the first radioimmunotherapy (RIT) with 2220 MBq/m2 131I-cG250 (n = 27) 1 week later. If no grade 4 hematologic toxicity was observed, a second low-dose 131I-cG250 (n = 20) was given 3 months later. When blood clearance was not accelerated, a second RIT of 131I-cG250 was administered at an activity-dose of 1110 MBq/m2 (n = 3) or 1665 MBq/m2 (n = 16). Patients were monitored weekly for toxicity, and tumor size was evaluated by computed tomography once every 3 months intervals. RESULTS: The maximum-tolerated dose (MTD) of the second RIT was 1,665 MBq/m2 because of dose-limiting hematological toxicity. Based on an intention-to-treat analysis, after two RIT treatments, the disease stabilized in five of 29 patients, whereas it remained progressive in 14 of 29 patients. Two patients received no RIT, and eight of 29 received only one 131I-cG250 RIT because of grade 4 hematologic toxicity, formation of human antichimeric antibodies, or disease progression. CONCLUSION: In patients with progressive end-stage RCC, the MTD of the second treatment was 75% of the MTD of the first RIT. In the majority of patients, two cycles of 131I-cG250 could be safely administered without severe toxicity. No objective responses were observed, but occasionally two RIT doses resulted in stabilization of previously progressive disease. 相似文献
80.
Peter Nieboer Ciska Buijs Sjoerd Rodenhuis Caroline Seynaeve Louk V A M Beex Elsken van der Wall Dick J Richel Marianne A Nooij Emile E Voest Pierre Hupperets Nanno H Mulder Winette T A van der Graaf Els M TenVergert Harm van Tinteren Elisabeth G E de Vries 《Journal of clinical oncology》2005,23(33):8296-8304
PURPOSE: Determine whether standard or high-dose chemotherapy leads to changes in fatigue, hemoglobin (Hb), mental health, muscle and joint pain, and menopausal status from pre- to post-treatment and to evaluate whether fatigue is associated with these factors in disease-free breast cancer patients. PATIENTS AND METHODS: Eight hundred eighty-five patients were randomly assigned between two chemotherapy regimens both followed by radiotherapy and tamoxifen. Fatigue was assessed using vitality scale (score < or = 46 defined as fatigue), poor mental health using mental health scale (score < or = 56 defined as poor mental health) both of Short-Form 36, muscle and joint pain with Rotterdam Symptom Checklist, and Hb levels were assessed before and 1, 2, and 3 years after chemotherapy. RESULTS: Fatigue was reported in 20% of 430 assessable patients (202 standard-dose, 228 high-dose) with at least a 3-year follow-up, without change over time or difference between treatment arms. Mean Hb levels were lower following high-dose chemotherapy. Only 5% of patients experienced fatigue and anemia. Mental health score was the strongest fatigue predictor at all assessment moments. Menopausal status had no effect on fatigue. Linear mixed effect models showed that the higher the Hb level (P = .0006) and mental health score (P < .0001), the less fatigue was experienced. Joint (P < .0001) and muscle pain (P = .0283) were associated with more fatigue. CONCLUSION: In 3 years after treatment, no significant differences in fatigue were found between standard and high-dose chemotherapy. Fatigue did not change over time. The strongest fatigue predictor was poor mental health. 相似文献