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Biomedical subjects

N H Mulder

Publications and source records attributed to N H Mulder.

At least 19 recordsLinked to original sources
PubMed1992

Relationship of cellular glutathione to the cytotoxicity and resistance of seven platinum compounds.

The role of glutathione (GSH) in the effectiveness of and resistance to 7 platinum compounds [5 Pt(II) and 2 Pt(IV) drugs] was evaluated in a 8.6-fold cisplatin (CDDP)-resistant human small cell lung cancer cell line (GLC4/CDDP), the parent GLC4 line, a 3.7-fold CDDP-resistant human embryonal carcinoma cell line (Tera-CP), and the parent Tera line (NTera2/D1). Resistance factors for both CDDP-resistant cell lines were determined after continuous incubation (4 days) with CDDP. Continuous incubation with the other studied platinum drugs revealed complete cross-resistance for carboplatin (CBDCA) and zeniplatin but less for enloplatin (ENLO) and iproplatin in both models. Tetraplatin and lobaplatin showed, respectively, partial and complete cross-resistance in GLC4/CDDP but no cross-resistance in Tera-CP. GSH level, but not glutathione S-transferase activity, of the 4 cell lines correlated with platinum drug concentrations inhibiting cell survival by 50% after continuous incubation (r = 0.86, P < 0.05). GSH depletion by DL-buthionine-S,R-sulfoximine (BSO) increased sensitivity, as measured after a 4-h exposure to the drugs, of GLC4/CDDP for CDDP 2.0-fold, for CBDCA 1.7-fold, for zeniplatin 1.7-fold, and almost to the level of the sensitive GLC4 for ENLO, whereas no effect was observed for lobaplatin and the Pt(IV) compounds iproplatin and tetraplatin. BSO-modulating effect was higher in the sensitive GLC4 line for most compounds; therefore reduction of resistance could be achieved only for CDDP and ENLO. In contrast to GLC4, no modulation occurred in Tera. In Tera-CP BSO increased sensitivity for CDDP 1.5-fold, for CBDCA 1.9-fold, and for zeniplatin 1.2-fold; no effect was observed for ENLO, lobaplatin, and the Pt(IV) compounds. Reduction of CDDP resistance by BSO was known to occur with identical cellular platinum levels and higher Pt-DNA binding in GLC4/CDDP. However, pretreatment with BSO followed by 4 h ENLO incubation increased cellular platinum levels in both GLC4 and GLC4/CDDP while Pt-DNA binding remained unchanged. In conclusion, GSH reflected sensitivity to platinum-containing drugs. However, since the involvement of GSH differed between the models and the various platinum drugs, the effect of modulation with BSO was unpredictable.

Antineoplastic Agents↗
PubMed1992

Effects of interleukin-3 after chemotherapy for advanced ovarian cancer.

To define the maximum tolerated dose and to study whether recombinant human interleukin-3 (rhIL-3) reduced chemotherapy-induced neutropenia and thrombocytopenia, 20 chemotherapy-naive patients with advanced ovarian cancer eligible for treatment with 6 cycles of carboplatin-cyclophosphamide every 4 weeks (day 1) were entered in a phase I/II open, single-center trial. Cohorts of five patients received during 7 days 1, 5, 10, or 15 micrograms/kg/d rhIL-3 (days 5 through 11) in cycles 1, 3, and 5 by continuous intravenous (IV) infusion or once daily subcutaneous (SC) administration. In control cycles 2, 4, and 6, no rhIL-3 was administered. rhIL-3 significantly increased the recovery of leukocyte, neutrophil, and platelet counts, especially at 5, 10, and 15 micrograms/kg rhIL-3. rhIL-3 also increased basophil, eosinophil, monocyte, and lymphocyte counts at this dose steps. Effects on reticulocytes were limited. No difference in efficacy between SC and IV rhIL-3 treatment was found. Chemotherapy postponement for insufficient bone marrow recovery was necessary in 22 of 45 control cycles versus 2 of 49 rhIL-3 cycles (P less than .001). Platelet transfusions were required in 7 of 45 control cycles versus 3 of 50 rhIL-3 cycles (P less than .5). rhIL-3 up to 10 micrograms/kg/d could be administered without severe side effects. At 15 micrograms/kg/d, rhIL-3 headache was dose-limiting. Other side effects were fever, flu-like symptoms, nausea, skin rash, flushing, facial erythema, and urticaria. Liver toxicity occurred in rhIL-3 and control cycles. rhIL-3 slightly increased tumor necrosis factor alpha, C-reactive protein, and serum amyloid A plasma levels, whereas no effect on IL-6 plasma levels was observed. rhIL-3 administered SC appears to be an interesting hematopoietic growth factor for reduction of chemotherapy-induced myelotoxicity.

Adolescent↗
PubMed1992

Changes in rectal epithelial cell proliferation and intestinal bile acids after subtotal colectomy in familial adenomatous polyposis.

Subtotal colectomy and ileorectal anastomosis in familial adenomatous polyposis patients can induce temporary regression of adenomas in the rectum. The mechanism for this phenomenon is unclear. We evaluated the effect of colectomy on rectal mucosal proliferation, in relation to changes in bile acid metabolism. Four familial adenomatous polyposis patients were studied before and 3-6 months after surgery, and eight others 7-22 years postoperatively. Within 6 months after surgery, the size of the proliferative zone of the colonic crypts was found to be reduced (P less than 0.05). The proliferative activity of total colonic crypts was not affected within this period. More than 7 years postoperatively, increased cell proliferation of total crypts (P less than 0.02), as well as mid (P less than 0.05) and basal (P less than 0.05) crypt compartments, were observed compared to shortly after colectomy. In duodenal bile, deoxycholic acid was absent shortly after operation, whereas several years after operation only a small fraction (2%) was present. Fecal secondary bile acid excretion diminished after colectomy and did not change several years postoperatively. In postoperative stools only, small proportions of ursocholic and ursodeoxycholic acids (about 5% each) were consistently found. As subtotal colectomy causes a temporary decrease in the length of the proliferative zone of rectal crypts toward a normal pattern, this may explain regression of rectal polyps. This temporary effect may be mediated, at least in part, by decreased amounts of cytotoxic secondary bile acids in the rectal lumen.

Adenomatous Polyposis Coli↗
PubMed1992

Long-term follow-up of cardiovascular risk factors in patients given chemotherapy for disseminated nonseminomatous testicular cancer.

OBJECTIVE: To assess cardiovascular risk factors over time in patients who received chemotherapy for disseminated testicular cancer and were apparently cured. DESIGN: Cohort study. SETTING: Referral center. PATIENTS: Fifty-seven consecutive patients (median age, 28 years; range, 16 to 43 years) who received cisplatin-containing chemotherapy between 1978 and 1985. MEASUREMENTS: Serum cholesterol and high-density lipoprotein (HDL) levels, body mass index (BMI), blood pressure, kidney function, and hormonal status were monitored during follow-up after chemotherapy (median follow-up, 88 months; range, 56 to 143 months). The BMI and cholesterol values obtained 4 to 6 years after chemotherapy were compared with values from a sample of healthy, age-matched Dutch men; the cholesterol level was also compared with that of 31 patients treated with orchidectomy for stage I disease. RESULTS: The mean cholesterol level in patients at the start of chemotherapy was 3.96 +/- 0.98 mmol/L [153 +/- 38 mg/dL], increasing 4 to 6 years later to 6.12 +/- 1.20 mmol/L [237 +/- 46 mg/dL] (P less than 0.001); 49 of 57 patients had an elevated low-density lipoprotein (LDL) cholesterol level (greater than 3.4 mmol/L [130 mg/dL]), with a mean level of 4.47 +/- 1.05 mmol/L [173 +/- 41 mg/dL]. Compared with a sample of healthy Dutch men, the chemotherapy group had an elevated cholesterol level (P less than 0.05). At 4 to 6 years, the mean HDL cholesterol level was 0.76 +/- 0.18 mmol/L [29 +/- 7 mg/dL], which was low compared with that of the healthy Dutch men (P less than 0.05). The mean BMI for all patients was 2.8% higher than expected 4 to 6 years after chemotherapy (P less than 0.01) but was not higher than expected 7 to 10 years after chemotherapy. CONCLUSIONS: In addition to other known late side effects of chemotherapy in patients with testicular cancer, hypercholesterolemia and overweight might represent risk factors for cardiovascular disease in such patients, especially in those who are younger.

Adolescent↗
PubMed1992

In vitro response of human small-cell lung-cancer cell lines to chemotherapeutic drugs; no correlation with clinical data.

Three cell lines derived from small-cell lung carcinoma (SCLC) tumors of patients who had no clinical response after treatment with a multi-drug regimen were compared to 3 cell lines derived from tumors of patients who, upon treatment, showed a complete clinical response. These 2 groups of cell lines were considered to represent the in vitro counterparts of the 2 extremes of the clinical spectrum of sensitivity for chemotherapeutic drugs in small-cell lung cancer. To assess whether the in vivo (in)sensitivity of a tumor to a certain drug regimen is retained in vitro, the cell lines were tested for drug sensitivity using the microtiter-well tetrazolium assay and the results were compared with the in vivo data. No correlation was found. Since in vitro models using cell lines are based on the assumption that a cell line reflects the properties of the tumor from which it is derived, several additional parameters such as MAb staining against different SCLC-associated antigens and DNA content were analyzed in the biopsies and the cell lines. The results showed that selection of discrete tumor-cell populations in vitro occurs. Results of in vitro chemosensitivity testing for individual SCLC patients should be interpreted with caution.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Increased sensitivity of an adriamycin-resistant human small cell lung carcinoma cell line to mitochondrial inhibitors.

The energy metabolism of an atypical multidrug resistant human small cell lung carcinoma cell line (GLC4/ADR) was studied. The glycolytic rate was 30% reduced and the glucose-6-phosphate dehydrogenase activity 2-fold increased in GLC4/ADR compared to the parental sensitive line (GLC4). Although mitochondrial respiration activities were similar in both cell lines, GLC4/ADR was more sensitive to the antimitochondrial drugs doxycycline and oligomycin, while cross-resistance was observed for the glycolytic inhibitor 2-deoxyglucose and for the antimitochondrial drug rhodamine-123. Continuous incubation with doxycycline induced a dramatic reduction of mitochondrial mRNAs in both cell lines, whereas a strong reduction of the nuclear-coded mRNA for subunit IV of cytochrome c oxidase was induced in GLC4/ADR only. Incubation with doxycycline had an additive effect on the cytotoxicity of adriamycin in both cell lines. Thus, a form of collateral sensitivity to antimitochondrial drugs may exist in atypical multidrug resistant cell lines.

Adenosine Triphosphate↗
PubMed1992

Pharmacokinetics of parenteral 13-cis-retinoic acid formulations in rats.

The pharmacokinetics of three 13-cis-retinoic acid formulations were studied after intraperitoneal (ip) administration to rats. Rats were given ip injections of 2.5 mg of 13-cis-retinoic acid per 360 g of body weight; the drug was administered as an alkaline solution, suspended in corn oil, or as a mixture with polysorbate 80. The alkaline solution was also given intravenously (iv) via the tail vein as a control. The mean elimination rate constant, calculated from data from iv administration, was 0.72 +/- 0.088 h-1 (r = 0.988). The peak concentration in plasma and the time to reach this maximum were 14 mg/L and 0.5 h, 22 mg/L and 2 h, and 10 mg/L and 1 h for the drug administered as an alkaline solution, suspended in corn oil, and as a mixture with polysorbate 80, respectively. The areas under the concentration-time curve (concentration in plasma versus time) were 34.9 +/- 8.78 mg.h/L for the iv dose and 34.1 +/- 9.97, 62.4 +/- 32.3, and 25.9 +/- 12.0 mg.h/L for the ip doses of alkaline solution, suspension in oil, and mixture with polysorbate 80, respectively. Because of the rapid increase of concentration in plasma, which is identical to that of the iv profile, and the ease of its handling and preparation, the ip administered alkaline solution is the preferable formulation.

Animals↗
PubMed1992

A phase I-II study of 14-days continuous infusion of 5-fluorouracil with weekly bolus leucovorin in metastatic colorectal carcinoma.

A consecutive phase I and phase II study of a 14-days continuous infusion schedule of 5-fluorouracil with weekly bolus injection leucovorin was performed in 10 and 21 patients, respectively. Chemotherapy courses were repeated every 4 weeks. 1 patient in the phase I study was pretreated, all the others had no prior chemotherapy. 300 mg/m2 continuous infusion of 5-fluorouracil for 14 days could not be combined with any dose of leucovorin 20-200 mg/m2 without severe toxicity, mainly gastrointestinal. A 5-fluorouracil dose of 200 mg/m2 day for 2 weeks, combined with weekly bolus injection of 200 mg/m2 leucovorin was found to be feasible. The phase II study was performed at this dose level. In 21 patients a response rate of 5/21 [23.8%, 95% confidence interval (CI) 8.2-47.1%] was observed, and the overall response rate was 8/29 (27.6%, 95% CI 12.7-47.2%). Responses were observed in patients with liver (4), lung (1), abdominal (1), and multiple (2) metastases. Median survival was 14.5 months. Toxicity was low, mucositis WHO grade 1-2 being most frequent (36/113 courses = 31.9%). Patients' acceptance of this continuous infusion schedule was generally good.

Adult↗
PubMed1992

Combination therapy with cisplatin: modulation of activity and tumour sensitivity.

Although cisplatin is applied with success in clinical oncology, this success is limited because some cancers are initially unresponsive to cisplatin or become so during treatment. In this review, some strategies to overcome this problem are discussed. Among these are combination with the differentiation inducing agent, retinoic acid, combination with radiotherapy, and the use of hyperthermia.

Animals↗
PubMed1992

A phase I-II study with intraperitoneal cisplatin plus systemic etoposide in patients with minimal residual ovarian cancer.

In patients with residual ovarian cancer after standard platinum-based induction, dose intensification was achieved by intraperitoneal administration of cisplatin 90 mg/m2 with intravenous Na thiosulphate and increasing dosages of etoposide. 40 patients entered the study, 4 on 200 mg/m2, 6 on 400 mg/m2, 22 on 600 mg/m2 and 8 on 800 mg/m2 etoposide. The optimal dose for etoposide was 600 mg/m2. 29 patients on the two highest dose steps were evaluable for response. 14 patients reached a complete remission, which was surgically confirmed in 6. All these patients initially had tumour residuals smaller than 1 cm. 3 patients had a partial response, 4 had stable disease and 8 progressed. At a maximal follow-up of 2 years (median 12 months), median time to progression was 12 months and median overall survival was 14 months. Of the 14 patients with complete remission, 2 relapsed at 9 and 11 months. Apart from a rash, in 4 of 22 patients at 600 mg/m2 and in 5 of 8 at 800 mg/m2 etoposide, the main toxicity was leukopenia grade 3-4 in 58% of cycles on 600 and in 76% at 800 mg/m2 etoposide. Leukopenic fever, however, occurred only three times; thrombocytopenia was rare. Cycles had to be delayed sporadically and the etoposide dose was reduced in 9% of all cycles at 600 and in 11% at 800 mg/m2. Intraperitoneal instillation of cisplatin gave no peritoneal symptoms. Intraperitoneal cisplatin with intravenous etoposide was tolerable and effective for patients with small tumour residuals after induction for stage III ovarian cancer.

Adult↗
PubMed1992

Stability of the new anticancer platinum analogue 1,2-diaminomethyl-cyclobutane-platinum(II)-lactate (lobaplatin; D19466) in intravenous solutions.

The chemical stability of the new anticancer platinum analogue 1,2-diaminomethyl-cyclobutane-platinum(II)-lactate (D19466) in infusion media was studied in an accelerated stability testing experiment with a selective HPLC-UV method. Variables were time, temperature, light, concentration, and infusion mixture. Mean reaction rate constants of decomposition were, respectively, 0.9555 *10(-2), 2.127 *10(-2), and 4.221 *10(-2) hr-1 at 37, 56, and 66 degrees C at a concentration of 200 mg/L in normal saline. From the Arrhenius equation, shelf lives (5% loss) at 4, 22, 37, and 121 degrees C were, respectively, calculated to be 41.6, 13.2, 5.7, and 0.15 hr. Mean reaction rate constant in 5% dextrose was 3.106 *10(-2) hr-1 (200 mg/L; 56 degrees C) and differed from that in normal saline (P less than 0.005). Mean reaction rate constant in Ringer lactate was 2.084 *10(-2) hr-1 (200 mg/L; 56 degrees C) (P greater than 0.05). There was no influence of normal daylight on the rate of decomposition. It is recommended to prepare D19466 infusions in normal saline. Chemical stability is then maximal 12 hr at room temperature or 24 hr at 4 degrees C. No protection against normal daylight is required. Sterilization by heat is not possible.

Antineoplastic Agents↗
PubMed1992

Modulation of cis-diamminedichloroplatinum(II) resistance: a review.

In this review an inventory is made of agents used to circumvent cis-diamminedichloroplatinum(II) (CDDP) resistance in vitro and in vivo. Agents that affect CDDP accumulation and membrane related systems, cytoplasmic defense mechanisms, as well as DNA accessibility and repair are reviewed. In resistant cell lines that have decreased accumulation, this can be restored by hyperthermic treatment. With or without effects on accumulation compounds that affect cell signal transduction often increase CDDP cytotoxicity. Calcium channel blockers and calmodulin inhibitors do not seem to be uniformly good modulators of CDDP resistance. For transduction modulators as well as cellular calcium affecting agents mechanisms are mainly unclear or controversial. Glutathione appears, with the now available agents, to be the most promising target for modulation of cytoplasmic defense mechanisms. At the nuclear level the inhibition of DNA repair related enzymes as well as the use of modified nucleosides to interfere with repair is studied in various cell lines. Results with these agents suggest opportunities for clinically feasible cytotoxicity modulation. DNA accessibility could in vitro be affected, but seems to be an unreliable target for modulation. Whenever possible the resistance mechanism affected and the mode of action of the modulator are discussed. As an alternative for modulation another method of overcoming CDDP resistance namely the application of CDDP analogues is considered.

Animals↗
PubMed1992

Recombinant interferon alpha-2b in patients with metastatic apudomas: effect on tumours and tumour markers.

Malignant carcinoid tumours, islet cell tumours and medullary carcinomas of the thyroid are tumours with similar clinical features. In patients with unresectable or metastatic tumours leukocyte interferon (IFN) and recombinant human (rh) IFN have demonstrated efficacy. Twenty-four evaluable patients with progressive tumours were treated with 2.5 megaunits rh IFN alpha-2b, administered once daily subcutaneously, for a median duration of 7 months (range 0.5-37+). Two carcinoid patients demonstrated a response in tumour size, 80% showed stable disease (SD). Sixty percent of the carcinoid patients with elevated urinary 5-hydroxyindoleacetic (5-HIAA) levels reached a biochemical partial response of the urinary 5-HIAA levels (median duration 13.5 months). In the patients with an islet cell or medullary tumour and an elevated tumour marker, the marker did not further increase. Of the 12 carcinoid patients evaluable for a symptomatic response, ten (83%) experienced a relieve of symptoms. IFN alpha-2b dose reduction or discontinuation due to toxicity was necessary in three and ten patients, respectively. No neutralising IFN alpha-2b antibodies developed despite prolonged treatment. In conclusion, IFN alpha-2b had a beneficial effect in patients with progressive tumours, while long-term IFN alpha-2b treatment did not augment neutralising antibodies. In view of the IFN alpha-2b-related toxicity, administration of IFN alpha-2b on alternating days may be preferable.

Adenoma, Islet Cell↗
PubMed1992

Peripheral blood lymphocyte number and phenotype prior to therapy correlate with response in subcutaneously applied rIL-2 therapy of renal cell carcinoma.

The phenotype of peripheral blood lymphocytes of 27 renal cell carcinoma patients before and at the end of subcutaneously given rIL-2 therapy was determined by two colour flow cytometry. Therapy induced changes in peripheral blood leucocyte composition and phenotypes were comparable to those reported for intravenously given rIL-2. The present paper shows a correlation between the 'activation status' of the patient before therapy and eventual response.

Adult↗