Search Results
Results 251 - 300 of 1774
< 1 2 3 4 5 6 7 8 9 10 11 >
Liu Xiaoqi - - 2005
Experiments from several different organisms have demonstrated that polo-like kinases are involved in many aspects of mitosis and cytokinesis. Here, we provide evidence to show that Plk1 associates with chaperonin-containing TCP1 complex (CCT) both in vitro and in vivo. Silencing of CCT by use of RNA interference (RNAi) in mammalian ...
Groschel Bettina - - 2005
We have identified four small molecules that boost transduction of cells by human immunodeficiency virus (HIV) and investigated their mechanism of action. These molecules include etoposide and camptothecin, which induce DNA damage by inhibiting religation of cleaved topoisomerase-DNA complexes, taxol, which interferes with the function of microtubules, and aphidicolin, which ...
Schmiederer Michael - - 2005
1,3-Butadiene (BD) causes genetic damage, including adduct formation, sister chomatid exchange, and point mutations. Previous studies have focused on the types of genetic damage and tumors found after long-term exposure of rodents to butadiene. This study examined the effect of the most active BD metabolite, butadiene diepoxide (BDO2), on cell ...
Woo Sang Hyeok - - 2005
Arsenic trioxide (As2O3, diarsenic oxide) has recently been reported to induce apoptosis and inhibit the proliferation of various human cancer cells derived from solid tumors as well as hematopoietic malignancies. In this study, the in vitro effects of As2O3 and tetraasrsenic oxide (As4O6) on cell cycle regulation and basic fibroblast ...
Graff Pål - - 2005
We have studied hypoxia-induced cell cycle arrest in human cells where the retinoblastoma tumour suppressor protein (pRb) is either functional (T-47D cells) or abrogated by expression of the HPV18 E7 oncoprotein (NHIK 3025 cells). Cells of both types are arrested in a restriction point in late G1, here denoted as ...
Jackson Mark W - - 2005
The progression of normal cells from G2 into mitosis is stably blocked when their DNA is damaged. Tumor cells lacking p53 arrest only transiently in G2, but eventually enter mitosis. We show that an important component of the stable G2 arrest in normal cells is the transcriptional repression of more ...
Bolige Aoen - - 2005
Cell population growth is gated to occur in particular circadian phases, which has been known for over four decades in various organisms including cyanobacteria and human. However, little is known as to which cell cycle phases from G1 to M are primarily regulated by the circadian rhythm or when in ...
Munitic Ivana - - 2005
The commitment of naive T cells to proliferate is a function of the strength and duration of stimuli mediated by the TCR and coreceptors. Ranges of 2-20 h of stimulation have been reported as necessary in vitro. Whether T cells actually experience uninterrupted stimulation for such long periods under physiological ...
Tu Xiaoming - - 2005
Expression of the cdc2-related kinase 3 (CRK3) together with expression of CRK1, -2, -4, or -6, were knocked down in pairs in the procyclic and bloodstream forms of Trypanosoma brucei, using the RNA interference technique. Double knockdowns of CRK3 and CRK2, CRK4, or CRK6 exerted significant growth inhibition and enriched ...
Martinsson Hanna-Stina - - 2005
The restriction point (R) separates the G1 phase of continuously cycling cells into two functionally different parts. The first part, G1-pm, represents the growth factor dependent post-mitotic interval from mitosis to R, which is of constant length (3-4 h). The second part, G1-ps, represents the growth factor independent, pre-S phase ...
Davy Clare E CE Division of Virology, National Institute for Medical Research, London, NW7 1AA, United - - 2005
Human papillomavirus type 16 (HPV16) can cause cervical cancer. Expression of the viral E1 E4 protein is lost during malignant progression, but in premalignant lesions, E1 E4 is abundant in cells supporting viral DNA amplification. Expression of 16E1 E4 in cell culture causes G2 cell cycle arrest. Here we show ...
Miyano Junko - - 2005
Pretreatment of Hep G2 cells with beta-naphthoflavone (BNF 1-25microM) significantly increased cytosolic sulfation activities of 4-hydroxypropranolol (4-OH-PL) racemate. The profile was similar to those of sulfations towards dopamine and triiodothyronine in the same cytosolic fractions. Kinetic studies of 4-OH-PL sulfation in Hep G2 cytosolic fractions revealed that V(max) values increased ...
Olsen P A - - 2005
Oligonucleotide-based sequence alteration in living cells is a substantial methodological challenge in gene therapy. Here, we demonstrate that using corrective single-stranded oligonucleotides (ssODN), high and reproducible sequence correction rates can be obtained. CHO cell lines with chromosomally integrated multiple copy EGFP reporter genes routinely show rates of 4.5% targeted sequence ...
Easwaran Hariharan P - - 2005
Many cellular processes are regulated by cell cycle dependent changes in protein dynamics and localization. Studying these changes in vivo requires methods to distinguish the different cell cycle stages. Here we demonstrate the use of DNA Ligase I fused to DsRed1 as an in situ marker to identify S phase ...
Zhao Richard Y - - 2005
Progression of cells from G2 phase of the cell cycle to mitosis is a tightly regulated cellular process that requires activation of the Cdc2 kinase, which determines onset of mitosis in all eukaryotic cells. In both human and fission yeast (Schizosaccharomyces pombe) cells, the activity of Cdc2 is regulated in ...
Dai Jin-ming - - 2005
AIM: To investigate the effect of antisense oligodeoxynucleotides (ASODN) targeting Pim-2 on cell proliferation of DU-145 cells. METHODS: Three ASODN targeting Pim-2 were designed and synthesized. After transfection with ASODN, cell proliferation was analyzed using an MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] assay. In addition, Pim-2 mRNA, protein levels, and cell cycles ...
Weinert Brian T - - 2005
P element excision generates a DNA double-strand break at the transposon donor site. Genetic studies have demonstrated a strong bias toward repair of P element-induced DNA breaks by homologous recombination with the sister chromatid, suggesting that P element excision occurs after DNA replication, in G2 of the cell cycle. We ...
Obermann Ellen C - - 2005
Peripheral B-cell lymphomas representing 90% of lymphoid neoplasms are divided into low- and high-growth fraction lymphomas. Here we investigate regulation of DNA replication licensing during B-cell lymphomagenesis. Combined analysis of origin licensing factors Mcm2 and geminin with the proliferation marker Ki67 in SLL/CLL, MCL, DLBCL and Burkitt lymphoma reveals for ...
Derenzini Massimo - - 2005
Cell growth is closely related to cell proliferation and an adequate ribosome biogenesis appears to be necessary for cell duplication. In the present study, we have investigated the relationship between rRNA synthesis and cell cycle progression. For this purpose, in a first set of experiments, we evaluated the effect of ...
Adamson Aaron W - - 2005
SN1 DNA methylating agents such as the nitrosourea N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) elicit a G2/M checkpoint response via a mismatch repair (MMR) system-dependent mechanism; however, the exact nature of the mechanism governing MNNG-induced G2/M arrest and how MMR mechanistically participates in this process are unknown. Here, we show that MNNG exposure results ...
Zalatnai Attila - - 2005
Malignant neoplasms consist of heterogeneous cell populations and their cellular elements proliferate asynchronously. Since the tumor cells of various cell cycle phases respond differently to many chemotherapeutic drugs, attempts at synchronization seemed to be a promising way to achieve a more powerful antineoplastic effect. Mainly based on in vitro data, ...
Wong Connie - - 2005
BACKGROUND: Mammalian cells have been reported to have a p53-dependent tetraploidy checkpoint that blocks cell cycle progression in G1 in response to failure of cell division. In most cases where the tetraploidy checkpoint has been observed cell division was perturbed by anti-cytoskeleton drug treatments. However, other evidence argues against the ...
Ding Juan - - 2005
The inhibitory effects of two kinds of selective cyclooxygenase-2 inhibitors on the proliferation of human carcinoma of larynx Hep-2 in vitro and their corresponding mechanisms were investigated. Hep-2 cells were cultured with two kinds of selective cyclooxygenase-2 inhibitors (Sc-58125 and Celecoxib) at various concentrations for 24 h. Morphological changes were ...
Kadota Yasuhiro - - 2005
The molecular links between the cell cycle and defense responses in plants are largely unknown. Using synchronized tobacco BY-2 cells, we analyzed the cell cycle dependence of elicitor-induced defense responses. In synchronized cultured apoaequorin-expressing cells, the increase in cytosolic free Ca2+ induced by a proteinaceous elicitor, cryptogein, was greatly suppressed ...
van Opstal Ang?lique - - 2005
Progression through the cell cycle of mammalian cells is dependent upon external factors such as growth- and ECM factors. These factors exert their effect predominantly during the G1 phase of the cell cycle. When cells are cultured in suspension or when growth factors are withdrawn from the medium, cells will ...
Mansour Amal - - 2004
Chronic B cell malignancies are often chemoresistant and the development of new therapeutic modalities is a high priority. Many B cell malignancies have autocrine production of IL-10, which regulates B cell growth and differentiation. Here we demonstrate that the soy isoflavone genistein, a tyrosine kinase inhibitor, rapidly decreased IL-10 secretion ...
Aylon Yael - - 2004
DNA double-strand breaks (DSBs) are dangerous lesions that can lead to genomic instability and cell death. Eukaryotic cells repair DSBs either by nonhomologous end-joining (NHEJ) or by homologous recombination. We investigated the ability of yeast cells (Saccharomyces cerevisiae) to repair a single, chromosomal DSB by recombination at different stages of ...
Massagué Joan - - 2004
Before replicating DNA during their reproductive cycle, our cells enter a phase called G1 during which they interpret a flood of signals that influence cell division and cell fate. Mistakes in this process lead to cancer. An increasingly complex and coherent view of G1 signalling networks, which coordinate cell growth, ...
Hodge Rebecca D - - 2004
Neurogenesis in the developing cerebral cortex of mice occurs in the dorsal telencephalon between embryonic day 11 (E11) and E17, during which time the majority of cortical projection neurons and some glia are produced from proliferating neuroepithelial cells in the ventricular zone. The number of cells produced by this process ...
Visanji James M - - 2004
Benzyl isothiocyanate and phenethyl isothiocyanate, two aromatic phytochemicals present in substantial concentrations in edible vegetables of the genus Brassica, were investigated for their effects on Caco-2 cell proliferation. Benzyl and phenethyl isothiocyanate inhibited DNA synthesis, with 50% inhibitory concentrations of 5.1 and 2.4 micromol/L, respectively, and significantly increased the doubling ...
Horn S - - 2004
The inositol 5-phosphatase SHIP (SHIP-1) is a negative regulator of signal transduction in hematopoietic cells and targeted disruption of SHIP in mice leads to a myeloproliferative disorder. We analyzed the effects of SHIP on the human leukemia cell line Jurkat in which expression of endogenous SHIP protein is not detectable. ...
Yang Pei-Ming - - 2004
Chinese hamster ovary K1 (CHO K1) cells are very sensitive to cadmium (Cd) toxicity. They were used to investigate the effect of Cd on cell cycle progression. Cells were cultured with 0.1, 0.4, 1 or 4 microM Cd for various time intervals. There was no difference in growth rate when ...
Zhou Rui - - 2004
The cell cycle phase distributions of Hz-AM1 cells grown in monolayer culture were G1 = 49.7 +/- 3.3%, S = 22.7 +/- 3.8% and G2/M = 27.8 +/- 4.2% without >4N DNA content. The culture doubling time was about 40 h and the duration of the G1, S and G2/M ...
Belibasakis G N - - 2004
The cytolethal distending toxin (Cdt) is produced by several Gram-negative bacterial species and causes growth arrest and morphological alterations in mammalian cells. Actinobacillus actinomycetemcomitans, which is involved in the pathogenesis of localized aggressive periodontitis, also produces a Cdt that affects periodontal connective tissue cells. The aim of this study was ...
Jaiswal Aruna S - - 2004
In the present study, we investigated the mechanisms by which zinc causes growth arrest in colon cancer cells. The results suggest that zinc treatment stabilizes the levels of the wild-type adenomatous polyposis coli (APC) protein at the post-translational level since the APC mRNA levels and the promoter activity of the ...
Arai Masayoshi - - 2004
The DNA-damaging agent bleomycin arrests the cell cycle at the G2 phase of Jurkat cells defective in the G1 checkpoint, and microtubule-acting colchicine arrests it at the M phase. Boromycin itself, an actinomycete metabolite, showed no effect on the cell cycle status of Jurkat cells at least up to 340 ...
Cardoen S - - 2004
To explain why 2-chloro-2'-deoxyadenosine (CdA) is unable to block DNA synthesis and cell cycle progression, and paradoxically enhances progression from G1 into S phase in the CdA-resistant leukemia EHEB cell line, we studied its metabolism and effects on proteins regulating the transition from G1 to S phase. A low deoxycytidine ...
May Tobias - - 2004
To employ physiological mechanisms to control cell growth primary cells were reversibly immortalized using the SV40 TAg. The cells showed a fibroblast-like morphology. When the expression of the TAg was turned off, the cells arrested in the G0/G1 cell cycle phase. The cell culture could be kept for over 1 ...
Kadota Yasuhiro - - 2004
The molecular links between cell cycle control and the regulation of programmed cell death are largely unknown in plants. Here we studied the relationship between the cell cycle and elicitor-induced cell death using synchronized tobacco BY-2 cells. Flow cytometry and fluorescence microscopy of nuclear DNA, and RNA gel-blot analyses of ...
Hsu Ya-Ling - - 2004
In this study, we report the proapoptotic effect of saikosaponin d in two liver cancer cell lines, Hep G2 and Hep 3B cells. Treatment with saikosaponin d decreased the cell proliferation of Hep G2 and Hep 3B cells in a dose dependent manner. In Hep G2, saikosaponin d blocked the ...
Kuroda Taruho S - - 2004
We have identified a novel nucleolar protein, PAP-1-associated protein-1 (PAPA-1), after screening the interacting proteins with Pim-1-associated protein-1 (PAP-1), a protein that is a phosphorylation target of Pim-1 kinase. PAPA-1 comprises 345 amino acids with a basic amino-acid cluster. PAPA-1 was found to be localized in the nucleolus in transfected ...
Freie Brian W - - 2004
Fanconi anemia (FA) is a complex, heterogeneous genetic disorder composed of at least 11 complementation groups. The FA proteins have recently been found to functionally interact with the cell cycle regulatory proteins ATM and BRCA1; however, the function of the FA proteins in cell cycle control remains incompletely understood. Here ...
Ferreira Miguel Godinho - - 2004
Several considerations suggest that levels of the two major modes of double-strand break (DSB) repair, homologous recombination (HR), and nonhomologous end joining (NHEJ), are regulated through the cell cycle. However, this idea has not been explicitly tested. In the absence of the telomere-binding protein Taz1, fission yeast undergo lethal telomere ...
Bernstein Kara A - - 2004
Without ribosome biogenesis, translation of mRNA into protein ceases and cellular growth stops. We asked whether ribosome biogenesis is cell cycle regulated in the yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, and we determined that it is not regulated in the same manner as in metazoan cells. We therefore turned our ...
Guo Jinbai - - 2004
Cell cycle progression of Saccharomyces cerevisiae cells was monitored in continuous cultures limited for glucose or nitrogen. The G1 cell cycle phase, before initiation of DNA replication, did not exclusively expand when growth rate decreased. Especially during nitrogen limitation, non-G1 phases expanded almost as much as G1. In addition, cell ...
Gerenday Anna - - 2004
We have established baseline conditions for investigating the interaction of the insect steroid hormone 20-hydroxyecdysone (20E) with the cell cycle in the C7-10 cell line from the mosquito, Aedes albopictus. As is the case with Drosophila melanogaster cells, treatment of C7-10 cells with 20E inhibits proliferation. In the presence of ...
Zraly Claudia B - - 2004
SNR1 is an essential subunit of the Drosophila Brahma (Brm) ATP-dependent chromatin remodeling complex, with counterparts in yeast (SNF5) and mammals (INI1). Increased cell growth and wing patterning defects are associated with a conditional snr1 mutant, while loss of INI1 function is directly linked with aggressive cancers, suggesting important roles ...
Dolznig Helmut - - 2004
Continuously proliferating cells exactly double their mass during each cell cycle. Here we have addressed the controversial question of if and how cell size is sensed and regulated. We used erythroblasts that proliferate under the control of a constitutively active oncogene (v-ErbB) or under the control of physiological cytokines (stem ...
Blagosklonny Mikhail V MV Brander Cancer Research Institute, New York Medical College, Hawthorne, New York, - - 2004
Paclitaxel (PTX), a microtubule-active drug, causes mitotic arrest leading to apoptosis in certain tumor cell lines. Here we investigated the effects of PTX on human arterial smooth muscle cell (SMC) cells. In SMC, PTX caused both (a) primary arrest in G(1) and (b) post-mitotic arrest in G(1). Post-mitotic cells were ...
Uetake Yumi - - 2004
Failure of cells to cleave at the end of mitosis is dangerous to the organism because it immediately produces tetraploidy and centrosome amplification, which is thought to produce genetic imbalances. Using normal human and rat cells, we reexamined the basis for the attractive and increasingly accepted proposal that normal mammalian ...
< 1 2 3 4 5 6 7 8 9 10 11 >