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Compared with solid tumor patients, those with hematological malignancies are at particular risk of chemotherapy-induced nausea and vomiting (CINV) because of their young age, exposure to highly-emetogenic induction, consolidation and salvage regimens, the high-dose conditioning regimens used before stem cell transplantation (SCT), and the heavy psychological burden of such treatments. In the absence of prophylaxis, around 75% of patients undergoing SCT experience delayed CINV. With first-generation 5-HT(3) receptor antagonists, only about 20% are completely protected from nausea and vomiting, and this frequent and debilitating adverse event has not been fully addressed. In contrast to solid tumors, there are no internationally agreed guidelines for the prevention and treatment of CINV in hematological malignancies. Work on a consensus is urgently required. The second-generation 5-HT(3) antagonist palonosetron is highly effective in preventing CINV in patients with solid tumors. The extended half-life of this agent and its mechanisms of action including allosteric binding, positive cooperativity and 5-HT(3) receptor internalization, may make it particularly effective in controlling delayed CINV. Although controlled comparisons against first-generation 5HT(3) agents have not yet been conducted in the setting of SCT, available evidence suggests that palonosetron may prove beneficial in preventing CINV in high risk patients with hematological malignancies.  相似文献   
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ObjectivePresurgical, window of opportunity trials have been proposed as a model to assess the activity of preventive and therapeutic interventions in a cost-effective manner in prostate cancer (CaP). The aim of the study was to explore karyometry as a method for monitoring the efficacy of intervention with preventive agents in patients with CaP.Materials and methodsThe material used in this investigation was from the 2F study, i.e., an Italian prospective randomized phase IIb presurgical study of finasteride vs. low-dose flutamide vs. placebo in men with CaP. Image analysis was performed in 16 cases treated with finasteride, 24 with flutamide, and 20 with placebo. For all these cases, CaP and normal looking secretory epithelium were present in the pretreatment biopsies as well as the post-treatment ex-vivo biopsies obtained from the radical prostatectomy specimens.ResultsTo establish a direction of nuclear change from normal to malignancy, i.e., the so-called line of progression, a discriminant function was derived with the normal looking epithelium in the pretreatment biopsies as one endpoint, and the CaP in the pretreatment biopsies as the other. The discriminant function was then applied to the post-treatment groups. The increase in relative nuclear area was the dominant feature. In the placebo group, 15 out of 20 CaP (75%) cases had a higher discriminant function score at the end of study, with a significant increase of the mean score by 90%. The flutamide treated CaP cases had increased discriminant function scores in 19 out of 24 cases (79%) and an increase of the mean score by 43%; the 5 cases with lower scores involved only minor reductions. In contrast, the finasteride treated CaP cases had increased discriminant function scores for 8 out of 16 cases (50%), but the increase in the mean score was by only 8%.ConclusionThis exploratory study establishes that karyometric monitoring can track the results of subtle nuclear changes induced by preventive interventions in men with CaP, thus allowing assessment of agent activity in a cost-effective manner.  相似文献   
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Mevinolin is a potent inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase; EC 1.1.1.34), an enzyme that catalyzes the rate-limiting step in cholesterol biosynthesis. We have been studying the hepatic distribution of reductase with immunofluorescence microscopy and liver ultrastructure with electron microscopy in normal and drug-treated rats. In control animals, only about 20% of the hepatocytes were reductase positive. These cells were localized in the periportal lobular zones. The numbers of positive hepatocytes in animals given mevinolin or cholestyramine (or both) were directly proportional to the activities of the HMG-CoA reductase determined biochemically. This induction of HMG-CoA reductase immunofluorescence was centered periportally. Rats given 0.075% mevinolin alone had a homogeneous distribution of reductase staining in their hepatocyte cytoplasm, whereas a combination of 0.25% mevinolin and 3% cholestyramine caused a 150-fold increase in enzyme activity and induced prominent juxtanuclear immunofluorescent globules of HMG-CoA reductase in all hepatocytes. With electron microscopy, these bodies were composed of tightly packed stacks of smooth endoplasmic reticulum cysternae and aggregates of branched smooth endoplasmic reticulum tubules. Our data suggest that a subpopulation of periportal rat hepatocytes may be uniquely specialized for cholesterol synthesis.  相似文献   
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Hoang  T; Haman  A; Goncalves  O; Wong  GG; Clark  SC 《Blood》1988,72(2):823-826
The effects of recombinant interleukin-6 (IL-6) on the proliferation of blast precursors present in the peripheral blood of patients with acute myeloblastic leukemia (AML) was investigated. IL-6 had little effect by itself; however, it synergized with granulocyte macrophage colony- stimulating factor (GM-CSF) and interleukin-3 (IL-3) in the stimulation of AML blast colony formation. Responsiveness of blast progenitors to IL-6 was heterogeneous. On normal bone marrow cells the same synergy was observed on granulocyte and monocyte precursors (GM-CFC), while there was no significant effect on erythroid and multipotential precursors.  相似文献   
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