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Objectives: This study sought to evaluate the dose-dependent effects of adenosine A1-receptor blockade on diuresis and renal function in patients with acute decompensated heart failure (ADHF) and renal impairment or diuretic resistance., Background: Intravenous loop diuretics are the mainstay of therapy for patients with ADHF. Treatment, however, may be complicated by diuretic resistance and/or worsening renal function., Methods: We carried out a pair of randomized, double-blind, placebo-controlled, proof-of-concept studies in 2 clinically challenging ADHF populations., Results: In the ADHF protocol, 146 patients with volume overload and an estimated creatinine clearance (CrCl) of 20 to 80 ml/min were randomized to placebo or 1 of 4 doses of KW-3902 (rolofylline) infused over 2 h daily for up to 3 days. On day 1, KW-3902 monotherapy increased urine output during the first 6 h (445, 531, 631, and 570 ml in the 2.5-, 15-, 30-, and 60-mg groups, respectively) compared with placebo (374 ml; p = 0.02). On day 2, serum creatinine decreased in all KW-3902 groups and increased with placebo (p = 0.04). By day 4 or day of discharge if earlier, intravenous furosemide administration tended to be lower in the KW-3902 groups compared with placebo (p = 0.10). In the diuretic-resistant protocol, 35 patients with an average CrCl of 34 ml/min were randomized to a single infusion of placebo, 10, 30, or 60 mg of KW-3902. Compared with placebo, KW-3902 increased hourly urine volume and estimated CrCl with peak effects occurring at 2 to 3 h and at 24 h, respectively. Adverse events were not different between placebo and KW-3902., Conclusions: In patients with ADHF and volume overload, KW-3902, an adenosine A1-receptor antagonist, enhances the response to loop diuretics and may have a renal protective effect.

The biochemical pathways involved in CD40 signaling have been extensively studied in B cells and B cell lines, and appear to be primarily initiated by recruitment of the tumor necrosis factor (TNF) receptor-associated factor (TRAF) signaling proteins to the CD40 cytoplasmic domain. Signaling pathways activated through CD40 in monocytes/macrophages have not been characterized as well as in B cells. Using human monocytes and the human monocytic cell line THP1, we examined signal transduction events induced by CD40 engagement with its ligand, CD154. In human monocytes, all TRAF mRNAs were expressed constitutively and CD40 ligation resulted in a strong up-regulation of TRAF1 mRNA. In THP1 cells, CD40 ligation induced expression of TRAF1 and TRAF5 mRNAs. Engagement of CD40 in both monocytes and THP1 cells led to the rapid and transient activation of the extracellular signal-regulated kinases (ERK) 1 and 2, and to low levels of JNK activation. No CD40-dependent activation of p38 mitogen-activated protein kinase (MAPK) was found. In CD154-stimulated monocytes and THP1 cells the upstream ERK1/2 activator, MAPK kinase (MEK) 1/2, and downstream substrate, c-Myc, were activated. By blocking activation of ERK1/2 with a MEK-specific inhibitor, PD98059, CD40-dependent secretion of the pro-inflammatory cytokines, TNF-alpha, IL-6 and IL-8, was demonstrated to be linked to the ERK1/2 pathway. The ERK1/2 pathway did not appear to be involved in up-regulating TRAF1 and TRAF5 mRNAs in THP1 cells. Collectively, these results suggest distinct differences between B cells and monocytic cells in CD40-dependent activation of MAPK pathways.

Interleukin-17 is a T cell derived pro-inflammatory cytokine exhibiting multiple biological activities in a variety of cells and believed to fine tune all general phases of hematopoietic response. However, the signaling mechanism of this novel cytokine remains unknown. The purpose of this study was to determine whether Interleukin-17 induces tyrosine phosphorylation of proteins and to find out whether the raf-1 kinase signaling pathway is involved in mediating its signaling. Using immunoblotting and immunocomplex kinase assays, we report that the early signaling events triggered by rhIL-17 involves rapid tyrosine phosphorylation of several cellular proteins including raf-1 within 0.5 to 30 min. Optimal stimulation of tyrosine phosphorylation was observed with 0.5 to 1.0 ng/ml of Interleukin-17. Further, Interleukin-17 stimulates rapid activation of raf-1 kinase. These findings provide the first evidence that the mechanism of IL-17 signaling involves rapid tyrosine phosphorylation and activation of raf-1 serine/threonine kinase., (Copyright 1999 Academic Press.)

Objectives: (i) To assess the efficacy and tolerability of tropisetron when used for acute and delayed cisplatin-induced emesis. (ii) To investigate whether dexamethasone added to tropisetron improves the control of emesis for patients who do not achieve a complete response to tropisetron alone. (iii) To assess sex of the patient and alcohol intake as prognostic factors for nausea and vomiting., Design: A prospective open label phase II trial over one or two cycles of chemotherapy. Data collection was based on observed response and patients' self-reporting., Setting: Twenty Australian tertiary care hospitals in 1994., Patients: 102 male and female patients from 18 to 75 years with histologically confirmed malignancy receiving their first chemotherapy containing > or = 50 mg/m2 cisplatin., Intervention: In Cycle 1 tropisetron 5 mg was given intravenously before chemotherapy on Day 1, then 5 mg orally before breakfast on Days 2 to 6. In Cycle 2, dexamethasone 20 mg intravenously on Day 1, then 8 mg orally on Days 2 to 6 could be added to tropisetron if a complete antiemetic response had not been achieved in Cycle 1., Main Outcome Measures: Number of vomiting episodes and severity of nausea for 6 days after chemotherapy; severity of side effects; patient satisfaction with chemotherapy treatment; oestradiol levels in women; and past alcohol consumption in men and women., Results: (i) The complete response rate (CR) for acute emesis in Cycle 1 was 64% (95% confidence interval [CI], 54%-72%), with 84% (95% CI, 76%-90%) having < or = 2 vomits. The CR for delayed emesis was 24% (95% CI, 17%-32%). The CR for acute nausea was 56% (95% CI, 47%-66%), with 97% (95% CI, 91%-99%) having < or = 2 nausea episodes. The CR for delayed nausea was 21% (95% CI, 14%-30%). Seventy-one patients received Cycle 2. The main side effects were headache (20 patients) and constipation (16 patients). The control of acute emesis was rated as "good" or "very good" by 68% of investigators; 85% rated the tolerability of treatment as "good" or "very good". Treatment was rated as "very satisfactory" or "satisfactory" by 52% of patients. (ii) The CR for acute emesis with dexamethasone added was 78% (95% CI, 64%-88%). (iii) Women with lower oestradiol levels had better control of emesis, although this difference was not statistically significant. Chronic alcohol intake and binge drinking were strongly associated with a complete acute antiemetic response., Conclusions: Tropisetron was effective for acute cisplatin-induced emesis; adding dexamethasone enhanced this response. Both single and combined therapy had less effect on delayed emesis. The impact of alcohol on control of emesis is a chronic rather than acute phenomenon which requires prospective testing.

Site-directed mutagenesis was used to construct mutant Trp repressors with each of the 38 possible single amino acid changes of the first 2 amino acid residues (Ile79 and Ala80) in the second "recognition" alpha-helix of the helix-turn-helix DNA-binding motif. Eight of these mutant repressors with Ile79 and Ala80 changes are more active than the wild-type protein when tryptophan is limiting, and are super-aporepressors. Eleven mutant repressors have extended DNA-binding specificies in vivo, and bind operators which the wild-type repressor cannot. One mutant repressor, Lys79, has a classical altered specificity phenotype in vivo, and binds the wild-type trp operator less well than wild-type repressor, yet binds a mutant operator better than wild-type repressor. A site-specific nuclease was derived from Lys79 repressor by constructing a double-mutant protein with Lys79 and a sole cysteine residue, Cys49, and alkylating this cysteine with a 1,10-phenanthroline-copper adduct. This nuclease has an altered specificity of DNA binding in vitro. When activated by the addition of thiol and hydrogen peroxide, the Lys79 nuclease cleaves operator DNA within its new recognition sequence with high efficiency.