We developed previously a resistant cell line, CEM/C2, from the human leukemia cell line CCRF-CEM by stepwise selection in camptothecin. This cell line is 974-fold more resistant to camptothecin than parental cells. Resistance is only partially explained by 2-fold reductions in topoisomerase I protein and mRNA levels. We further investigated biochemical and molecular features of topoisomerase I...

The Caenorhabditis elegans hermaphrodite nervous system is composed of 302 neurons that fall into at least 118 diverse classes. Here we describe cfi-1, a gene that contributes to the development of neuronal diversity. cfi-1 promotes appropriate differentiation of the URA sensory neurons and inhibits URA from expressing the male-specific CEM neuronal fate. The UNC-86 POU homeodomain protein is p...

The metabolism of 5-fluorouracil (FUra) was examined in two human lymphocyte cell lines, CCRF-CEM (T-leukemic) and LAZ-007 (Epstein-Barr virus-transformed B), which have widely differing FUra sensitivities. CEM cells have orotate phosphoribosyltransferase but no uridine or thymidine phosphorylase activity. Consistent with this, the FUra growth inhibition and the synthesis of fluorouridine triph...

Phospholipase D (PLD) has been suggested to mediate epidermal growth factor (EGF) signaling. However, the molecular mechanism of EGF-induced PLD activation has not yet been elucidated. We investigated the importance of the phosphorylation and compartmentalization of PLD1 in EGF signaling. EGF treatment of COS-7 cells transiently expressing PLD1 stimulated PLD1 activity and induced PLD1 phosphor...

AIM Adhesion of composite resin and pulp capping biomaterials remarkably influences treatment outcomes. This in vitro study aimed to compare the shear bond strength of composite resin to calcium enriched mixture (CEM) cement, mineral trioxide aggregate (MTA) and resin modified glass ionomer (RMGI) with or without acid etching. MATERIALS AND METHODS A total of 90 cylindrical acrylic blocks con...

INTRODUCTION Nano-hydroxyapatite (NHA) has been used for regeneration of osseous defects. Calcium-enriched mixture (CEM) cement is also used for various dental treatments. This trial compared the efficacy of NHA and CEM cement for direct pulp capping (DPC) of sound primary teeth. METHODS AND MATERIALS In this randomized clinical trial with split-mouth design, after attaining informed consent,...

STATEMENT OF THE PROBLEM Alkaline pH can affect the physical and chemical properties and sealing ability of apical plug material. Calcium hydroxide is used as an intracanal medication to complete disinfection of root canals. It raises the pH of environment to alkaline value. PURPOSE The aim of this in vitro study was to evaluate and compare the effect of alkaline pH on the sealing ability of ...

In vivo efficacy testing of monoclonal antibody-based drugs specific for human leukemias is hampered by the paucity of suitable animal models, due in part to the inability of many anti-human monoclonal antibodies to cross-react with antigens expressed in animal tissues or cells. Moreover, human leukemic cells have proven difficult to establish in immunosuppressed mice except as solid tumors. We...

N-Trifluoroacetyladriamycin-14-valerate (AD32) and N-trifluoroacetyladriamycin (AD41) have been compared with Adriamycin and daunorubicin in CCRF-CEM human lymphoblastic cells. All four agents produce DNA damage, as measured by alkaline unwinding methods. Thymidine incorporation, a measure of DNA synthesis, is inhibited by AD32 and AD41 and completely blocked by the other drugs. AD32 and AD41 i...