The effect of preincubating purified Leydig cells in Eagle's medium and the subsequent effect of the mRNA synthesis inhibitor actinomycin D on LH-stimulated testosterone synthcsis has been investigated. The inhibitory effect obtained was found to decrease with the period of preincubation; with 0, 1, 2 and 3 h preincubation bcfore the addition of L H (100 ng/ml) 36.5 t 3.9, 31.2 k 2.5, 17.8 k 3....

Schaffer, Frederick L. (University of California, Berkeley), and Marjorie Gordon. Differential inhibitory effects of actinomycin D among strains of poliovirus. J. Bacteriol. 91:2309-2316. 1966.-Actinomycin D exerted a differential effect on the ability of strains of poliovirus to replicate in HeLa cells. LSc-2ab was studied as an example of a strain markedly inhibited by actinomycin; MEF(1) ser...

The number of lung "metastases" that develop from intravenously injected tumor cells is modified by the administration of certain carcinostatic agents. The number is increased by post-treatment with small amounts of mechlorethamine (HN~) or actinomycin D, but is decreased by larger amounts. Pretreatment with HN~ results in increased numbers of lung metastases. Pretreatment with actinomycin D, H...

1. An eightfold increase in the incorporation of [2-(14)C]acetate into liver cholesterol in vivo was observed 24hr. after starved rats had been given actinomycin D (0.5mg./kg. of body wt.). Liver cholesterol radioactivity declined faster in the treated animals, suggesting a greater rate of cholesterol turnover. 2. Liver slices from treated animals showed a tenfold increase in the incorporation ...

The telomeric repeat binding factor 2 (TRF2) specifically recognizes TTAGGG tandem repeats at chromosomal ends. Unexpectedly immunofluorescence studies revealed a prominent nucleolar localization of TRF2 in human cells, which appeared as discrete dots with sizes similar to those present in the nucleoplasm. The TRF2 dots did not overlap with dots stemming from the upstream binding factor (UBF) o...

The present study evaluated the effects of hyperthyroid state on lipid peroxidation and antioxidant enzymes in the crude (CF), post nuclear (PNF) and mitochondrial fractions (MF) of the fish liver. The in vivo injection of T3 (200ng) did not change the lipid peroxidation products, malondialdehyde (MDA) and conjugated dienes (CD), while actinomycin D (10microg), a potent mRNA inhibitor when admi...

OBJECTIVE To determine the effectiveness of 2 standard chemotherapy regimens for low-risk gestational trophoblastic disease according to the International Federation of Gynecology and Obstetrics (FIGO) staging system. METHODS From 2008 until 2010, 75 women with low-risk gestational trophoblastic disease received either pulsed actinomycin D (n=50) or 5-day methotrexate (n=25). The primary remi...

Interferon production was induced in a strain of human diploid foreskin cells with poly(I).poly(C). Cycloheximide was included in the culture medium at the time of addition of the inducer. Actinomycin D was added to the cultures 4 or 5 hr later, before the inhibition of protein synthesis was reversed at 6 hr. Thus, subsequent interferon synthesis had to be directed by messenger RNA synthesized ...

Regulation of transcription from the oncogene c-myc has an important role in the genesis of various tumors. Therefore, c-myc is a potential target for chemotherapy by drugs which are able to modify its activity directly. In this article, we identify the binding sites in the P1 and P2 promoter regions of c-myc for the intercalating antibiotics actinomycin D and elsamicin A. Gel retardation exper...

BACKGROUND Wilms tumor (WT) is the most common pediatric malignant primary renal tumor. One of the main drugs used in treatment is actinomycin-D. This was not readily available in Turkey at one time. Carboplatin was used in the primary treatment of WT in order to prevent delays in treatment. The aim of this study is to present the results of patients with WT receiving carboplatin or actinomycin...