Doses Greater (dose + greater)

Distribution by Scientific Domains


Selected Abstracts


Relationship of glutathione S-transferase genotypes with side-effects of pulsed cyclophosphamide therapy in patients with systemic lupus erythematosus

BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 4 2006
Shilong Zhong
Aims Cyclophosphamide (CTX) is an established treatment of severe systemic lupus erythematosus (SLE). Cytotoxic CTX metabolites are mainly detoxified by multiple glutathione S-transferases (GSTs). However, data are lacking on the relationship between the short-term side-effects of CTX therapy and GST genotypes. In the present study, the effects of common GSTM1, GSTT1, and GSTP1 genetic mutations on the severity of myelosuppression, gastrointestinal (GI) toxicity, and infection incidences induced by pulsed CTX therapy were evaluated in patients SLE. Methods DNA was extracted from peripheral leucocytes in patients with confirmed SLE diagnosis (n = 102). GSTM1 and GSTT1 null mutations were analyzed by a polymerase chain reaction (PCR)-multiplex procedure, whereas the GSTP1 codon 105 polymorphism (Ile,Val) was analyzed by a PCR-restriction fragment length polymorphism (RFLP) assay. Results Our study demonstrated that SLE patients carrying the genotypes with GSTP1 codon 105 mutation [GSTP1*-105I/V (heterozygote) and GSTP1*-105 V/V (homozygote)] had an increased risk of myelotoxicity when treated with pulsed high-dose CTX therapy (Odds ratio (OR) 5.00, 95% confidence interval (CI) 1.96, 12.76); especially in patients younger than 30 years (OR 7.50, 95% CI 2.14, 26.24), or in patients treated with a total CTX dose greater than 1.0 g (OR 12.88, 95% CI 3.16, 52.57). Similarly, patients with these genotypes (GSTP1*I/V and GSTP1*V/V) also had an increased risk of GI toxicity when treated with an initial pulsed high-dose CTX regimen (OR 3.33, 95% CI 1.03, 10.79). However, GSTM1 and GSTT1 null mutations did not significantly alter the risks of these short-term side-effects of pulsed high-dose CTX therapy in SLE patients. Conclusions The GSTP1 codon 105 polymorphism, but not GSTM1 or GSTT1 null mutations, significantly increased the risks of short-term side-effects of pulsed high-dose CTX therapy in SLE patients. Because of the lack of selective substrates for a GST enzyme phenotyping study, timely detection of this mutation on codon 105 may assist in optimizing pulsed high-dose CTX therapy in SLE patients. [source]


Mucosal melanoma of the nose and paranasal sinuses, a contemporary experience from the M. D. Anderson Cancer Center

CANCER, Issue 9 2010
Mauricio A. Moreno MD
Abstract BACKGROUND: Sinonasal mucosal melanoma is a rare disease associated with a very poor prognosis. Because most of the series extend retrospectively several decades, we sought to determine prognostic factors and outcomes with recent treatment modalities. METHODS: A retrospective chart review of 58 patients treated for sinonasal melanoma at a tertiary cancer center between 1993 and 2004. The patients were retrospectively staged according to the sinonasal American Joint Committee on Cancer (AJCC) staging system. Demographic, clinical and pathological parameters were identified and correlated with outcomes. RESULTS: There were 35 males and 23 females with a median age of 63 years; 56 patients were treated surgically and 33 received radiation therapy. According to Ballantyne's clinical staging system, 88% of the patients presented with stage I (local) disease. Classification by the AJCC staging classified yielded 27% of the patients with T1, 33% with T2, 21% with T3, and 19% with T4. T-stage and the degree of tumor pigmentation were associated with a worse survival (P = .0096 and P = .018, respectively), while pseudopapillary architecture was associated with a higher locoregional failure (P = .0144). Postoperative radiation therapy improved locoregional control when a total dose greater than 54 Gy was used (P = .0215), but did not affect overall survival. CONCLUSIONS: Tumor stage according to sinonasal AJCC staging system is an effective outcome predictor and should be the staging system of choice. Postoperative radiation therapy improves locoregional control when a higher dose and standard fractionations are used. Histological features such as pigmentation and pseudopapillary architecture are associated with worse outcome. Cancer 2010. © 2010 American Cancer Society. [source]


Clinical Efficacy and Safety of Recombinant Canine Erythropoietin in Dogs with Anemia of Chronic Renal Failure and Dogs with Recombinant Human Erythropoietin-Induced Red Cell Aplasia

JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2004
John F. Randolph
The efficacy and safety of recombinant canine erythropoietin (rcEPO) therapy was evaluated in 19 dogs with anemia of chronic renal failure (group 1) and 6 dogs with chronic renal failure and recombinant human erythropoietin (rhEPO)-induced red cell aplasia (group 2). Hematocrit (Hct) and absolute reticulocyte count (ARC) were monitored weekly for the first 8 weeks, CBC (including ARC) and serum iron profiles were evaluated monthly, and serum biochemical analyses were performed every 2 months for 6 (group 2) to 12 (group 1) months. For group 1 dogs, median Hct and ARC increased significantly during the 1st week of rcEPO treatment, and median Hct was sustained at >35% after week 5. In contrast, median Hct and ARC for group 2 did not change significantly with rcEPO treatment, even with doses greater than those used in group 1. Nevertheless, 2 (33%) of the 6 dogs in group 2 developed erythroid hyperplasia, reticulocytosis, and increases in Hct with rcEPO treatment. Although median systolic blood pressure did not change significantly in either group, 5 dogs developed systolic blood pressures a 180 mm Hg during the study. Appetite and energy level improved in most group 1 dogs with increases in Hct. Recombinant cEPO stimulated erythrocyte production in dogs with nonregenerative anemia secondary to chronic renal failure without causing the profound erythroid hypoplasia that can occur in rhEPO-treated dogs. Unfortunately, rcEPO was not as effective in restoring erythrocyte production in dogs that had previously developed rhEPO-induced red cell aplasia. [source]


Improved safety with equivalent asthma control in adults with chronic severe asthma on high-dose fluticasone propionate

RESPIROLOGY, Issue 3 2001
Norbert Berend
Objective: High-dose inhaled corticosteroids (ICS) have been associated with the same side-effects as oral corticosteroids. Beclomethasone dipropionate (BDP) and budesonide (BUD) in doses greater than 2000 ,g/day are used regularly in severe asthma, despite the fact that safety and efficacy data at such high doses are limited. Fluticasone propionate (FP) has been promoted as being twice as potent clinically as BDP or BUD at doses of 2000 ,g/day or less with a similar safety profile. The aim of this study was to compare the efficacy and safety of FP with BDP and BUD in 133 symptomatic adult asthmatics requiring at least 1750 ,g/day of BDP or BUD. Methodology: Patients fulfilling the entry criteria were randomized to receive either their regular ICS medication or FP at approximately half the microgram dose for 6 months in an open, parallel group study. The primary efficacy measure was based on morning peak expiratory flow measurements recorded by patients on daily record cards, while determination of safety was based on a number of endpoints including changes in bone turnover indices, the incidence of topical side-effects and assessments of quality of life. Results: It was shown that patients who were switched to FP, but not those continuing with BDP or BUD, had significant increases in levels of morning serum cortisol and the urine cortisol:creatinine ratio while maintaining asthma control. Serum osteocalcin and the pyridinoline:creatinine ratio, as well as the deoxypyridinoline:creatinine ratio, were also shown to increase only in the FP group. Subjective assessments such as quality of life score, the incidence and ease of bruising, and reports of hoarseness also favoured the FP group. Conclusions: It is concluded that, at the doses studied and with the delivery devices used clinically, FP is at least as effective as BDP/BUD in the management of severe asthma and may offer clinical advantages with respect to steroid-related adverse effects. [source]


Determining the Optimal Dose of Intravenous Fat Emulsion for the Treatment of Severe Verapamil Toxicity in a Rodent Model

ACADEMIC EMERGENCY MEDICINE, Issue 12 2008
Eric Perez MD
Abstract Objectives:, Recent animal studies have shown that intravenous fat emulsion (IFE) increases survival and hemodynamics in severe verapamil toxicity. However, the optimal dose of IFE is unknown. The primary objective was to determine the optimal dose of IFE based on survival in severe verapamil toxicity. Secondary objectives were to determine the effects on hemodynamic and metabolic parameters. The hypothesis was that there is a dose-dependent effect of IFE on survival until a maximum dose is reached. Methods:, This was a controlled dose-escalation study. Thirty male rats were anesthetized, ventilated, and instrumented to record mean arterial pressure (MAP) and heart rate (HR). Verapamil toxicity was achieved by a constant infusion of 15 mg/kg/hr. After 5 minutes, a bolus of 20% IFE was given. Animals were divided into six groups based on differing doses of IFE. Arterial base excess (ABE) was measured every 30 minutes. Data were analyzed with analysis of variance. Results:, The mean survival time for each dose of IFE was 0 mL/kg = 34 minutes, 6.2 mL/kg = 58 minutes, 12.4 mL/kg = 63 minutes, 18.6 mL/kg = 143.8 minutes, 24.8 mL/kg = 125.6 minutes, and 37.6 mL/kg = 130 minutes. Post hoc testing determined that the 18.6 mL/kg dose resulted in the greatest survival when compared to other doses. It increased survival 107.2 minutes (p = 0.004), 91.2 minutes (p = 0.001), and 80.8 minutes (p = 0.023) when compared to the lower doses of 0, 6.2, and 12.4 mL/kg, respectively. There was no added benefit to survival for doses greater than 18.6 mL/kg. The secondary outcomes of HR, MAP, and ABE showed the most benefit with 24.8 mL/kg of IFE at both 30 and 60 minutes. Conclusions:, The greatest benefit to survival occurs with 18.6 mL/kg IFE, while the greatest benefit to HR, MAP, and BE occurs at 24.8 mL/kg IFE. The optimal dose for the treatment of severe verapamil toxicity in this murine model was 18.6 mL/kg. [source]