Search results for "Dactinomycin"
showing 10 items of 17 documents
Nitric oxide increases the decay of matrix metalloproteinase 9 mRNA by inhibiting the expression of mRNA-stabilizing factor HuR.
2003
Dysregulation of extracellular matrix turnover is an important feature of many inflammatory processes. Rat renal mesangial cells express high levels of matrix metalloproteinase 9 (MMP-9) in response to inflammatory cytokines such as interleukin-1 beta. We demonstrate that NO does strongly destabilize MMP-9 mRNA, since different luciferase reporter gene constructs containing the MMP-9 3' untranslated region (UTR) displayed significant reduced luciferase activity in response to the presence of NO. Moreover, by use of an in vitro degradation assay we found that the cytoplasmic fractions of NO-treated cells contained a higher capacity to degrade MMP-9 transcripts than those obtained from contro…
Induction of apoptosis in human retinoblastoma cells by topoisomerase inhibitors
1998
PURPOSE:To examine the apoptotic effect induced in human retinoblastoma Y79 cells by camptothecin, etoposide, and amsacrine, to examine the effect of these drugs on the expression of many apoptosis-related modulators, and to test the antiapoptotic effect exerted by insulin-like growth factor-I (IGF-I). METHODS:Morphologic features of apoptosis were demonstrated using acridine orange- ethidium bromide staining and electron microscopy. DNA fragmentation was determined by means of an in situ cell detection procedure (TdT-dUTP terminal nick-end labeling [TUNEL]) or by electrophoresis on agarose gels and was quantified by enzyme-linked immunosorbent assay. The expression of apoptosis-related mod…
In vitro release of lectins by Phallusia mamillata hemocytes.
1991
Abstract α-Lactose specific lectins are released from Phallusia mamillata hemocytes during short-term cultures. The molecular weight of the subunits, the immunological cross-reaction and the sugar specificity suggest that the released lectins are similar to those isolated from the sonicated hemocytes. Because lectin release appears to take place independently of active protein synthesis, the possibility exists that lectins are pre-formed, stored in hemocytes and released when in vitro conditions stimulate the cells.
Induction of the fatty acid transport protein 1 and acyl-CoA synthase genes by dimer-selective rexinoids suggests that the peroxisome proliferator-ac…
2000
The intracellular fatty acid content of insulin-sensitive target tissues determines in part their insulin sensitivity. Uptake of fatty acids into cells is a controlled process determined in part by a regulated import/export system that is controlled at least by two key groups of proteins, i.e. the fatty acid transport protein (FATP) and acyl-CoA synthetase (ACS), which facilitate, respectively, the transport of fatty acids across the cell membrane and catalyze their esterification to prevent their efflux. Previously it was shown that the expression of the FATP-1 and ACS genes was controlled by insulin and by peroxisome proliferator-activated receptor (PPAR) agonists in liver or in adipose t…
Untersuchungen �ber den Einflu� des Actinomycins C (Sanamycin) auf das Blut und die blutbildenden Organe des Kaninchens sowie auf Knochenmarkskulturen
1955
Es wird uber Blutbild-, Knochenmarks-und Organbefunde von Kaninchen berichtet, die einer langeren Sanamycinbehandlung unterworfen wurden. 20 γ/kg taglich beeinflusten das Blutbild und die blutbildenden Organe nur geringgradig. 40 γ Sanamycin/kg verursachten eine Anamie mit weitgehender Aplasie des erythropoetischen Markanteils, die nach Absetzen des Mittels reversibel waren. 80 γ/kg taglich fuhrten zu einer erheblichen Beeintrachtigung des Allgemeinbefindens und einer Schadigung des gesamten Knochenmarkes. Die Grose der Milz war geringgradig, die der Lymphknoten meist stark reduziert.
Inhibitors acting on nucleic acid synthesis in an oncogenic RNA virus.
1971
IN infection with an oncogenic RNA virus, synthesis of viral RNA seems to be catalysed by an RNA dependent DNA polymerase in the host cell1–4. Several specific inhibitors of viral DNA polymerases have been found5–7 and Spiegelman8 has shown that the activity of viral enzymes depends strongly on the chemical composition of the template. We report here first a new highly specific poison of the Rauscher murine leukaemia virus (RMLV) DNA polymerases; second, several inactivators of the RNA and DNA template involved in the RMLV enzyme systems; and third, the action of actinomycin D on viral DNA polymerases and on host DNA/RNA polymerase. The results are discussed with respect to the influence of…
Synthesis of heat-shock proteins in developing sea urchins.
1981
Heating sea urchin embryos at 31°C greatly reduces the synthesis of the bulk proteins, whereas it highly stimulates the synthesis of some new proteins, the main ones being two closely migrating proteins of about 70,000 daltons. The production of heat-shock proteins is obtained only if the embryos are heated after hatching. Stages which produce heat-shock proteins survive heating, whereas earlier stages, not producing heat-shock proteins, do not survive. Heat-shock proteins are not produced in the presence of actinomycin D.
Extra-Adrenal Adult Neuroblastoma With Aberrant Germ Cell Marker Expression: Maturation After Chemotherapy as an Important Clue to a Challenging Diag…
2019
Adult neuroblastoma is an extremely infrequent neoplasm, usually occurring in the adrenal medulla or in the paraspinal sympathetic ganglia, as its childhood counterpart. We report a very unusual case of a Schwannian stroma-poor adult neuroblastoma of inguinal location, showing aberrant expression of germ cell markers: SALL4 and OCT4. This aberrant marker expression, the unusual positivity for NKX2.2 and the very scattered (instead of diffuse strong) PHOX2B expression, complicated the initial diagnosis. In this case, the posttreatment histological evaluation revealed the neuroblastic nature of the lesion. Neuroblastoma maturation after treatment is an unusual finding in adults, and in this …
Synaptic ribbons of the rat pineal gland: responses to in-vivo and in-vitro treatment with inhibitors of protein synthesis.
1990
To elucidate the role of protein synthesis in the nocturnal increase of synaptic ribbons in the rat pineal gland, actinomycin-D, which inhibits transcription, and cycloheximide, an inhibitor of translation, were used. To assure that the drugs were effective and to relate morphological changes to pineal biosynthetic phenomena, the activity of N-acetyltransferase and levels of pineal indoleamine were measured. Results of in-vivo, short-term and long-term treatment with either drug suggest that transcription of proteins related to synaptic ribbon formation occurs during the first half of the light phase, whereas translation takes place during the first few hours of the dark phase. In contrast,…
The DNA damage-induced decrease of Bcl-2 is secondary to the activation of apoptotic effector caspases.
2003
Apoptosis induced by DNA-damaging agents or radiation mainly proceeds through death receptor-independent caspase activation. The release of mitochondrial apoptogenic proteins, such as cytochrome c, into the cytoplasm leading to Apaf1-dependent activation of caspase-9 is a key event in this pathway. The permeability of the mitochondrial outer membrane is regulated by the various pro- and antiapoptotic Bcl-2 family proteins, and it is thought that DNA damage triggers apoptosis through the downregulation of antiapoptotic Bcl-2. Using murine embryonic fibroblasts (MEF) deficient and proficient in Apaf1, we show that DNA-damaging agents and radiation lead to a decline in Bcl-2 protein only in wt…