Belinda T Doyle

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Sphingolipids is the collective term ascribed to components of the sphingomyelin cycle. Modulation of the cellular levels of individual sphingolipids can induce a diverse range of cellular responses including apoptosis, proliferation, and cell cycle arrest. We present data showing that rhabdomyosarcoma cell lines, independent of lineage (alveolar(More)
We have demonstrated previously that interferon (IFN)-gamma sensitizes human colon carcinoma cell lines to the cytotoxic effects of 5-fluorouracil combined with leucovorin and to the thymidylate synthase inhibitor, ZD9331, dependent on thymineless stress-induced DNA damage, independent of p53. Here we demonstrate that the cyclin-dependent kinase (CDK)(More)
Inflammatory mediators delay neutrophil apoptosis, which contributes to the persistence of inflammation. The mechanisms responsible for this delay and resistance to Fas antibody-induced apoptosis are unknown but are dependent on protein synthesis. These proteins have been shown to inhibit caspase activity central to the induction of apoptosis. The(More)
PURPOSE Ureteral obstruction (UO) results in apoptosis of renal tubular epithelial cells. We postulated that mechanical deformation and inflammation contribute to the cellular loss that occurs as a result of UO and it is mediated through altered heat shock protein 70 (HSP-70) expression and the caspase cascade. MATERIALS AND METHODS Human HK-2 renal(More)
BACKGROUND Dysfunctional inflammatory responses have been implicated in several neonatal inflammatory disorders following infection and hypoxia. OBJECTIVES We aimed to study the effects of in vitro hypoxia and heat shock (HS) on normal adult and newborn neutrophil migration (CD11b) and persistence (apoptosis) following lipopolysaccharide (LPS)(More)
Mechanisms responsible for the termination of an inflammatory response include the activation of a genetic programme of cellular suicide termed apoptosis, which leads to the elimination of the cellular effectors of acute inflammation, particularly the neutrophil. However, delays in this response result in the persistence of inflammation and the development(More)
HL-60 cell differentiation into neutrophil like cells is associated with their induction of apoptosis. We investigated the cellular events that occur pre and post mitochondrial permeability transition to determine the role of the mitochondria in the induction of differentiation induced apoptosis. Pro-apoptotic Bax was translocated to and cleaved at the(More)
Human promyelocytic leukaemia cells (HL-60) differentiate into neutrophil-like cells that die spontaneously by apoptosis when treated with retinoic acid (RA). Inhibitors of apoptosis proteins (IAP) bind to and inhibit caspases 3, 7, and 9 activity and the induction of apoptosis. In this study, we demonstrate that undifferentiated HL-60 cells express IAP.(More)
Using synapses which form between somata of Helisoma neurons in cell culture we have studied the presynaptic regulation of synaptic transmission. GTP-binding proteins play important roles in regulating synaptic transmission through their actions on calcium currents, potassium currents and secretory apparatus. Heterotrimeric G proteins continuously regulate(More)
We have demonstrated previously that interferon (IFN)sensitizes human colon carcinoma cell lines to the cytotoxic effects of 5-fluorouracil combined with leucovorin and to the thymidylate synthase inhibitor, ZD9331, dependent on thymineless stress-induced DNA damage, independent of p53. Here we demonstrate that the cyclin-dependent kinase (CDK) inhibitor(More)
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