Использование барий-стронциевого карбонатита при изготовлении сварочных флюсов на основе техногенных отходов металлургического производства

В данной работе рассмотрена возможность использования барий-стронциевого карбонатита при изготовлении сварочных флюсов на основе шлака производства силикомарганца, а так же на основе ковшевых электросталеплавильных шлаков, образованных при производстве рельсовых марок стали. В серии опытов в лабораторных условиях изготавливали и исследовали различные составы сварочных флюсов, были определены химические составы наплавленного металла, проведен металлографический анализ.In this paper the possibility of using barium-strontium carbonatite in the manufacture of welding fluxes on the basis of slag from the production of silicomanganese, and based on ladle steelmaking slags formed in the production of rail steel grades. In a series of experiments in the laboratory have produced and investigated different compositions of welding fluxes, were determined the chemical compositions of the weld metal metallographic analysis

A phase I dose-finding study of 5-azacytidine in combination with sodium phenylbutyrate in patients with refractory solid tumors

Purpose: This was a phase I trial to determine the minimal effective dose and optimal dose schedule for 5-azacytidine (5-AC) in combination with sodium phenylbutyrate in patients with refractory solid tumors. The pharmacokinetics, pharmacodynamics, and antineoplastic effects were also studied. Experimental Design: Three dosing regimens were studied in 27 patients with advanced solid tumors, and toxicity was recorded. The pharmacokinetics of the combination of drugs was evaluated. Repeat tumor biopsies and peripheral blood mononuclear cells (PBMC) were analyzed to evaluate epigenetic changes in response to therapy. EBV titers were evaluated as a surrogate measure for gene re-expression of epigenetic modulation in PBMC. Results: The three dose regimens of 5-AC and phenylbutyrate were generally well tolerated and safe. A total of 48 cycles was administrated to 27 patients. The most common toxicities were bone marrow suppression-related neutropenia and anemia, which were minor. The clinical response rate was disappointing for the combination of agents. One patient showed stable disease for 5 months whereas 26 patients showed progressive disease as the best tumor response. The administration of phenylbutyrate and 5-AC did not seem to alter the pharmacokinetics of either drug. Although there were individual cases of targeted DNA methyltransferase activity and histone H3/4 acetylation changes from paired biopsy or PBMC, no conclusive statement can be made based on these limited correlative studies. Conclusion: The combination of 5-AC and phenylbutyrate across three dose schedules was generally well tolerated and safe, yet lacked any real evidence for clinical benefit. © 2009 American Association for Cancer Research

Phase 1 and pharmacologic study of MS-275, a histone deacetylase inhibitor, in adults with refractory and relapsed acute leukemias

MS-275 is a benzamide derivative with potent histone deacetylase (HDAC) inhibitory and antitumor activity in preclinical models. We conducted a phase 1 trial of orally administered MS-275 in 38 adults with advanced acute leukemias. Cohorts of patients were treated with MS-275 initially once weekly × 2, repeated every 4 weeks from 4 to 8 mg/m(2), and after 13 patients were treated, once weekly × 4, repeated every 6 weeks from 8 to 10 mg/m(2). The maximum-tolerated dose was 8 mg/m(2) weekly for 4 weeks every 6 weeks. Dose-limiting toxicities (DLTs) included infections and neurologic toxicity manifesting as unsteady gait and somnolence. Other frequent non-DLTs were fatigue, anorexia, nausea, vomiting, hypoalbuminemia, and hypocalcemia. Treatment with MS-275 induced increase in protein and histone H3/H4 acetylation, p21 expression, and caspase-3 activation in bone marrow mononuclear cells. No responses by classical criteria were seen. Our results show that MS-275 effectively inhibits HDAC in vivo in patients with advanced myeloid leukemias and should be further tested, preferably in patients with less-advanced disease

Caspase 3/caspase-activated DNase promote cell differentiation by inducing DNA strand breaks

Caspase 3 is required for the differentiation of a wide variety of cell types, yet it remains unclear how this apoptotic protein could promote such a cell-fate decision. Caspase signals often result in the activation of the specific nuclease caspase-activated DNase (CAD), suggesting that cell differentiation may be dependent on a CAD-mediated modification in chromatin structure. In this study, we have investigated if caspase 3/CAD plays a role in initiating the DNA strand breaks that are known to occur during the terminal differentiation of skeletal muscle cells. Here, we show that inhibition of caspase 3 or reduction of CAD expression leads to a dramatic loss of strand-break formation and a block in the myogenic program. Caspase-dependent induction of differentiation results in CAD targeting of the p21 promoter, and loss of caspase 3 or CAD leads to a significant down-regulation in p21 expression. These results show that caspase 3/CAD promotes cell differentiation by directly modifying the DNA/nuclear microenvironment, which enhances the expression of critical regulatory genes