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At least 415 records · Page 23Linked to original sources
PubMed1996

[Synchronizing therapy with plasmapheresis and cyclophosphamide in rapidly progressing systemic lupus erythematosis with kidney involvement].

12 patients with rapidly progressive systemic lupus erythematosus (SLE) combined with renal failure were treated for 6 months according to the following scheme: 3 consecutive procedures of plasmapheresis (60 ml/kg x 3), 3 consecutive pulse doses of cyclophosphamide (400 mg/m2 x 3), 3 prednisolone infusions (2 mg/kg x 3), oral cyclophosphamide (100-250 mg/day) and prednisolone (0.5 mg/kg with subsequent dose reduction). Dose of the drugs was controlled by blood leukocyte count and creatinine clearance. The patients were included in the trial in the preset time. All the patients had active SLE (33.5 +/- 2.7 U according to SLAM). 75, 25, 58.3, 33.4, 8.3% of patients had mixed, nephrotic, mesangiocapillary, mesangioproliferative, membraneous nephritis, respectively. 26 weeks of the treatment produced a response in 83.3% of the patients. The disease activity lowered to 12.8 +/- 2.9 U. Four-year survival reached 81%. Cytopenia developed in 25% of patients, deep hemopoiesis depression was not observed. Septic candidiasis arose in one woman on the third year of the follow-up. Clinical validity of the above method is stated in severe SLE.

Adult↗
PubMed2006

Tolerability of enteric-coated mycophenolate sodium to 1 year in combination with cyclosporine and corticosteroids in renal transplant recipients.

Enteric-coated mycophenolate sodium (EC-MPS) is therapeutically equivalent to mycophenolate mofetil, but delays release of mycophenolic acid until it reaches the small intestine. De novo renal transplant patients taking part in a 12-month, multicenter, randomized study received cyclosporine microemulsion (CsA-ME, early or delayed to day 6), EC-MPS, steroids, and interleukin-2 antagonist induction. Tolerability data relating to EC-MPS are reported. Ninety-seven patients were randomized to early CsA-ME and 100 patients to delayed CsA-ME. Median daily dose of EC-MPS was 1440 mg at all time points throughout the 12-month period. The most frequently reported adverse events were constipation, anemia, urinary tract infection, abdominal pain, leukopenia, and cytomegalovirus infection; there were four malignancies. Fifty patients (24.6%) discontinued EC-MPS prematurely by 12 months, including 42 patients (84%) who discontinued owing to adverse events. No patient discontinued treatment because of gastrointestinal adverse events. Two-thirds of patients (137 [67.5%]) maintained full EC-MPS dose throughout the 12-month study and did not require any dose reduction or dose interruption. EC-MPS is well tolerated in de novo renal transplant recipients when administered in combination with CsA-ME and steroids, with low rates of dose reductions or interruptions. Gastrointestinal adverse events were responsible for dose reduction or interruption in only 5% of patients.

Adrenal Cortex Hormones↗
PubMedDate not supplied

Clinical implications of chemotherapy-induced diarrhea in patients with cancer.

Diarrhea is a common, often dose-limiting toxicity associated with cancer chemotherapy treatment. However, the problem is not well recognized and frequently is not managed appropriately. The primary objectives of the current study were to describe the sociodemographic and clinical characteristics of cancer patients with chemotherapy-induced diarrhea (CID) and describe the clinical consequences of CID on treatment changes. This was a retrospective review of medical records from 378 cancer patients who experienced diarrhea while receiving chemotherapy at 25 geographically dispersed US cancer clinics. Severe diarrhea (National Cancer Institute-Common Toxicity Criteria grades 3 or 4) was experienced by about one third of patients during their chemotherapy. Patients who experienced CID underwent changes in their chemotherapy treatment, including dose reductions (45%), delays in therapy (71%), reduction in dose intensity (64%), and discontinuation of therapy (3%). Dose reductions were statistically significant. Although the majority of diarrhea was grade 1, almost one half of all patients required dosing reductions, and more than one half of these patients experienced dosing delays. Changes to chemotherapy treatment resulting from CID may ultimately impact patient clinical outcomes.

Aged↗
PubMed1999

Reductions in finger doses for radiopharmaceutical dispensing afforded by a syringe shield and an automatic dose dispenser.

A gamma extremity monitoring system (GEMS) has been used to measure finger doses during radio-nuclide dispensing procedures. GEMS uses a small semi-conductor probe that can be attached to a finger from which a continuous read-out can be obtained that is related to dose rate. The pattern of dose accumulation can be analysed to allow doses received from individual operations within a procedure to be evaluated. GEMS has been used to compare the radiation dose reduction afforded by a syringe shield and an automatic dose dispenser. Dispensing procedures were simulated using 10% of the activity normally administered in order to avoid problems with detector saturation. Results show that the syringe shield and the automatic dose dispenser reduced finger doses by more than a factor of 10 for the procedures tested. The disadvantages of the automatic dispenser tested were a failure to transfer activity in 10% of cases and a longer time taken for the dispensing process. GEMS has the potential to facilitate greater optimization of finger doses through analysis of finger dose patterns.

Dispensatories as Topic↗
PubMed2002

[Study of image quality (contrast) and reduction of patient dose by using heavy metal filters].

We studied image quality (contrast) and patient dose reduction using heavy metal filters in lumbar spine and abdomen x-ray examination. Heavy metal filters used in this study are gadolinium, holmium and ytterbium and these combinations. These filters have k-absorption edge in the range from 50 to 70 keV. Image quality and patient dose in 70-90 kV tube voltage with heavy metal filters were compared with 80 kV tube voltage without filter. Image quality was improved in four percent and patient dose could be reduced by 30%. However, tube loading increased from 1.6 to 2.2 times. It was found that the best filter choices gave better image and reduced patient dose compared to without filter.

Filtration↗
PubMed1988

Reduction of radiation dose and imaging costs in scoliosis radiography. Application of large-screen image intensifier photofluorography.

Photofluorography using a large-field image intensifier (Siemens Optilux 57) was applied to scoliosis radiography and compared with a full-size rare-earth screen/film technique. When scoliosis radiography (PA-projection) was performed on 25 adolescent patients, the photofluorographs were found to be of comparable diagnostic quality with full-size films. A close correspondence between the imaging techniques was found in the Cobb angle measurements as well as in the grading of rotation with the pedicle method. The use of photofluorography results in a radiation dose reduction of about one-half and considerable savings in direct imaging costs and archive space. In our opinion the method is particularly well-suited for follow-up and screening evaluation of scoliosis, but in tall patients the image field size of 40 x 40 cm restricts its usefulness as initial examination.

Adolescent↗
PubMed1978

Reduction of radiation dose to patients in xeroradiography.

A method for reducing the radiation dose received by the patient in xeroradiography is described. It is shown, theoretically, that a dose reduction of about 50% can be achieved, and measurements of skin exposure confirm reductions of this order. There is no appreciable loss of image quality, and the theory suggests that it may even be possible to enhance the visualization of soft tissue by this method.

Copper↗
PubMed2002

Calcineurin inhibitor nephrotoxicity: reduction in dose results in marked improvement in renal function in patients with coexisting chronic allograft nephropathy.

BACKGROUND: Calcineurin inhibitors (CNI) have significantly reduced the incidence of acute rejection. Nephrotoxicity however, may contribute to long-term allograft dysfunction. METHODS: Forty-six biopsies from patients who had been transplanted for more than 6 months were examined. Sixteen biopsies had evidence of chronic allograft nephropathy (CAN) alone, 21 biopsies had evidence of coexisting CAN in addition to histological evidence of calcineurin inhibitor nephrotoxicity (CNIN) while nine had neither evidence of nephrotoxicity nor CAN. Patients with evidence of nephrotoxicity underwent a reduction in dose of CNI while those with CAN alone had no change in therapy. Renal function was followed for a mean of 17.4 months after biopsy. RESULTS: The serum creatinine at the time of diagnostic renal biopsy was comparable between those with CAN alone (mean 0.25 +/- 0.18 mmol/L) and those with coexisting CNIN (mean 0.23 +/- 0.05 mmol/L, p=0.33). The patients with CNIN however, had a rapid improvement in renal function within 1 month after dose reduction. This was sustained for the duration of follow-up (mean serum creatinine 0.162 +/- 0.038 mmol/L at 1 yr after dose reduction; p=0.001). In comparison, those with CAN alone had a gradual decline in renal function with a serum creatinine at 1 yr after biopsy of 0.31 +/- 0.187, p=0.01. CONCLUSION: Reduction in the dose of CNI in those with histological evidence of nephrotoxicity resulted in a sustained improvement in renal function.

Calcineurin Inhibitors↗
PubMed2000

Sequence-dependent toxicity profile in modified FAMTX (fluorouracil-adriamycin-methotrexate) chemotherapy with lenograstim support for advanced gastric cancer: a feasibility study.

For advanced irresectible gastric cancer, sequential high-dose methotrexate and 5-fluorouracil (both on day 1) combined with adriamycin on day 15 (FAMTX regimen), cycled every 28 days, is a fairly effective but toxic treatment, with a high incidence of neutropenic fever, dose reductions and dose delays. In order to improve FAMTX toxicity, we studied the feasibility of two modified FAMTX regimens with lenograstim support. Seven advanced gastric cancer patients were treated with all three FAMTX drugs on day 1 followed by lenograstim 150 microgm(-2)for 10 days, in 21-day cycles (FUMA regimen). The next seven patients were treated with the same drugs at the same doses, but with adriamycin 1 day prior to methotrexate and 5-fluorouracil administration (AFUM regimen). Patients were monitored for toxicity, response, and survival. The total number of courses was 27 for FUMA and 35 for AFUM with a median of four courses per patient in each cohort. In the FUMA regimen, considerable toxicity consisting of mucositis and fatigue as well as grade 4 neutropenia occurred, and forced four out of seven patients to stop treatment. The consecutive AFUM regimen showed only mild toxicity, and all patients could finish treatment without dose reductions or delays. We found unanticipated and probably sequence-dependent toxicity profiles in two investigational, modified FAMTX schedules with lenograstim support, leading to high rates of dose-limiting toxicity in the FUMA regimen as opposed to mild toxicity in the AFUM regimen, even though the same total drug doses and treatment cycle length (dose intensity) were employed.

Adenocarcinoma↗
PubMed1999

Topical DMSO treatment for pegylated liposomal doxorubicin-induced palmar-plantar erythrodysesthesia.

PURPOSE: Chemotherapeutic regimens that utilize fluorouracil, cytarabine, and doxorubicin have been shown to cause a dermatologic syndrome known as hand-foot syndrome, or palmar-plantar erythrodysesthesia syndrome (PPES). Pegylated liposomal doxorubicin has proven effective in the treatment of AIDS-related Kaposi's sarcoma, ovarian cancer refractory to platinum and paclitaxel therapies, and metastatic breast cancer. In a study of the treatment of refractory epithelial cell ovarian cancers with lipozomal doxorubicin utilizing intravenous doses of 50 mg/m(2) every 3 weeks, grade 3 PPES was observed in 29% of patients (10/35) and required dose reductions and/or dose delay after a median of three therapy cycles. METHODS: Current methods to prevent pegylated liposomal doxorubicin-induced PPES include dose reduction, lengthening of the drug administration interval and ultimately, drug withdrawal. Topical 99% dimethylsulfoxide (DMSO) also has shown strong activity in treating tissue extravasation reactions during intravenous administration of doxorubicin. RESULTS: Two patients undergoing chemotherapy with pegylated liposomal doxorubicin, 50 mg/m(2) every 4 weeks, developed grade 3 PPE after three cycles. Their PPES resolved over a period of 1 to 3 weeks while receiving topical 99% DMSO four times daily for 14 days. CONCLUSIONS: While these results are promising, patients must be treated in a prospective study of this topical DMSO formulation to definitively document its therapeutic efficacy.

Administration, Topical↗
PubMed2000

Does P-glycoprotein play a role in anticancer drug pharmacokinetics?

The multidrug-resistance P-glycoprotein is a drug efflux transport protein abundantly present in various types of human cancer. The protein is encoded by the MDR1 gene and its function is sensitive to modulation by competitive inhibition. Clinical studies have indicated that inhibitors of P-glycoprotein function dramatically decrease the systemic clearance of anticancer agents, necessitating dose reduction. This dose reduction not only complicated the interpretation of toxicity and response data, but also presented a serious obstacle in the development and rational use of P-glycoprotein inhibitors. It is now evident that the pharmacokinetic interference between anticancer drugs and P-glycoprotein inhibitors is due primarily to competition for drug metabolizing enzymes. A wealth of recent experimental data shows that many of the previously tested P-glycoprotein inhibitors, including verapamil, cyclosporin A, and valspodar (SDZ PSC 833), are substrates and/or potent inhibitors of cytochrome P450 3A4 (CYP3A4). Future development and clinical use of potent P-glycoprotein modulators lacking high affinity for CYP3A4 should decrease the impact of these important drug interactions and will eventually result in improved therapeutic specificity and efficacy. Copyright 2000 Harcourt Publishers Ltd.

Journal Article↗
PubMed1998

A phase II study of carboplatin, cisplatin, interferon-alpha, and tamoxifen for patients with metastatic melanoma.

The purpose of this trial was to determine the toxicity and antineoplastic activity of cisplatin, carboplatin, tamoxifen, and interferon-alpha (IFN-alpha) in patients with advanced melanoma. Eleven patients with metastatic melanoma were enrolled. The patients received carboplatin 400 mg/m2 i.v. on day 0; cisplatin 25 mg/m2 i.v. on days 7, 14, and 21; tamoxifen 20 mg p.o. b.i.d. on days 0-27; and interferon-alpha 5 million units/m2 subcutaneously 3 times per week. Cycles were repeated every 28 days. Patients were assessed for tumor response at the end of 2 cycles. Toxicity was severe, with 14 of 24 cycles given requiring some form of dose reduction. Carboplatin dose reductions were related to bone-marrow toxicity, whereas IFN-alpha caused fatigue, arthralgias, myalgias, and fever. The overall response rate was 18% (2 partial responses [PRs]). The combination of cisplatin, carboplatin, tamoxifen, and IFN-alpha is active in advanced melanoma; however, the toxicity is unacceptable.

Adult↗
PubMed1977

Bromocriptine versus placebo in levodopa treated patients with Parkinson's disease.

Twenty patients with idiopathic parkinsonism who had been on optimal levodopa therapy for at least 3 months prior to the investigation and where effect of the treatment was decreasing or side effects were increasing, were treated with bromocriptine in a double-blind crossover trial during a 12 + 12 weeks period. Reduction in disability scores was found significant. Hyperkinesia was more frequent in the bromocriptine period than in the placebo period, but reduction of dose in six patients for this reason was not followed by deterioration. Both hyperkinesia and other side effects disappeared after dose reduction. Doses were 2.5 mg-40 mg. Bromocriptine seems a valuable supplement to previous therapy in these patients.

Aged↗
PubMed2000

[Full-field digital mammography: dose-dependent detectability of breast lesions and microcalcinosis].

OBJECTIVES: The study compares contrast-detail and microcalcification detectability of a full-field digital mammography (FFDM) to a state-of-the-art conventional screen-film mammography (SFM) by using different doses in the digital system. MATERIALS AND METHODS: The investigations were performed with an FFDM (Senographe 2000 D, GEMS) and an SFM system (Senographe DMR, GEMS) using a contrast-detail mammography phantom (CDMAM) and an anthropomorphic breast phantom with superimposed microcalcifications. The digital detector was exposed with standard dose of SFM and with a dose reduction of up to 75%. Contrast-detail curves and correct observation ratio (COR) were performed for the CDMAM phantom. ROC analysis with a confidence level ranging from 1 to 5 was done with the results of the anthropomorphic phantom. RESULTS: Digital mammography with the same dose revealed at least an equivalent or even higher detectability rate than conventional mammography, COR could be increased at about 10-25%. The ROC analysis yielded better results for the FFDM system. The same lesion detectability in digital mammography as in the conventional method was reached at a dose reduction of about 25%, concerning spot views even at higher reduction. Dose reduction in the anthropomorphic phantom resulted in a linear loss of detectability. The same detectability as in conventional mammography was reached, however, by a dose reduction of about 50%. CONCLUSION: The results suggest that FFDM is at least equivalent to or--as far as spot views are concerned--superior to conventional SFM concerning the detectability of simulated lesions. Thus, a potential of dose reduction is suggested.

Breast Diseases↗
PubMed2003

Racial disparity in the dose and dose intensity of breast cancer adjuvant chemotherapy.

PURPOSE: The purpose of this study was to investigate the impact of race and obesity on dose and dose intensity of adjuvant chemotherapy. METHODS: We abstracted data on patient/tumor characteristics, treatment course, physicians' intention to give a first cycle dose reduction, and reasons for dose reductions/delays from oncology records of 489 women treated from 1985 to 1997 in 10 treatment sites in two geographical regions. Administered doses and dose intensity were compared to standard regimens. Multivariate regression models determined the impact of race and body mass index (BMI) on dose proportion (actual:expected doses) and relative dose intensity (RDI) controlling for patient characteristics, comorbidity, chemotherapy regimen, site, and year of treatment. Logistic regressions explored race and BMI versus use of first cycle dose reductions. RESULTS: African-Americans received lower chemotherapy dose proportion and RDI than whites (0.80 vs. 0.85, p = 0.03 and 0.76 vs. 0.80, p = 0.01). In multivariate analyses, dose proportion was 0.09 lower (p = 0.002), and RDI was 0.10 (p < 0.001) lower in non-overweight African-Americans than whites. Obesity was associated with lower dose proportion (p < 0.01) and RDI (p < 0.03). Race and BMI were independently associated with first cycle dose reductions. Non-overweight African-Americans (p < 0.05) and overweight and obese African-American and white women (p < 0.001) were more likely to have first cycle dose reductions than non-overweight whites. CONCLUSION: We identified systematic differences in the administration of chemotherapy given to African-Americans and to overweight and obese women. These differences may contribute to documented disparities in outcome.

Adult↗
PubMed1997

Patient perceptions of psychological and physiological withdrawal symptoms and positive factors associated with gradual withdrawal from methadone maintenance treatment: a prospective study.

Psychological and physiological withdrawal symptoms and some positive factors were studied in 10 methadone maintenance treatment patients during methadone dose reduction. The subjective ratings were made during a period of 10 days around each reduction occasion, 3 days before dose reduction and 7 days after (i.e., within the periods). To permit comparisons of the subjects' ratings between earlier and later stages of the dose reduction process, a division has been made between the first half and the second half of the total reduction occasions (i.e., between the periods). Three of the patients completed the dose reduction, while the others interrupted their withdrawal attempts. The results show that the aggregate psychological symptoms were rated low, but that, as expected, they increased significantly from the first to the second half of the dose reduction. A significant increase of the psychological symptoms also occurred from the days before each reduction to the days after. The aggregate physiological symptoms were rated very low. A significant increase in rated withdrawal intensity is found within the reduction occasions. There were no significant changes with regard to the aggregate positive factors, either within or between the reduction occasions.

Adult↗
PubMed2001

Analyzing current practice patterns: lessons from Amgen's Project ChemoInsight.

PURPOSE/OBJECTIVES: To retrospectively review data on chemotherapy dose/dose intensity in patients with breast cancer. DATA SOURCES: Computerized database, published articles, and book chapter. DATA SYNTHESIS: Chart reviews were conducted of 20,106 patients with breast cancer from 1,135 oncology practices throughout the United States. More dose delays, dose reductions, and suboptimal dose intensity occur in patients who are 65 years of age or older. Overall, dose intensity was not achieved in 18.4% of patients, dose reductions occurred in 25.7% of patients, and dose delays occurred in 43.1% of patients. Neutropenia was often the cause of dose delays/reductions. CONCLUSIONS: A substantial number of patients with breast cancer experience chemotherapy dose delays or reductions. IMPLICATIONS FOR NURSING PRACTICE: Guidelines may help consistently manage primary and secondary prophylaxis of neutropenia. Nurses' can influence patients' attitudes about prescribed therapies.

Aged↗
PubMed1975

Biological detection of reduction in dose at the surface of volume sources containing beta emitters.

Dosimetry theory related to volume sources containing uniformly distributed beta-emitting radionuclides predicts a rapid drop in dose at the outer surface to approximately one half of the maximum dose within the volume. The purpose of this study was to determine if this reduction in surface dose could be observed using a measurable biological endpoint. In this study rats were injected with radiocolloids of either 198Au, 113In-m or 99Tc-m, to produce liver irradiation from their decay, or their livers were treated with external X-irradiation. After irradiation, a portion of the liver was surgically removed to stimulate cell division in the liver remnant revealing radiation damage in the form of chromosomal aberrations. The percentages of dividing cells with bridges were scored in the outer edges (0.45 mm) of the tissue sections and were compared to levels obtained from the central portion of the liver lobe. No significant difference was observed with X-irradiation or from 99Tc-m irradiation. However, irradiation with 198-Au and 113In-m (which emit large numbers of energetic electrons) produced significantly fewer aberrations in the outer layer when compared to the central portion. These differences in the distribution of biological damage allowed us to detect the predicted dose reduction at the surface of volume sources containing beta emitters.

Animals↗