THE SYNTHESIS OF DNA AND RNA IN HUMAN CARCINOMATOUS ENDOMETRIUM IN SHORT-TERM INCUBATION IN VITRO AND ITS RESPONSE TO OESTRADIOL AND PROGESTERONE

1970 ◽  
Vol 48 (1) ◽  
pp. 29-38 ◽  
Author(s):  
S. NORDQVIST
Keyword(s):  
Nucleic Acids ◽  
Dna Synthesis ◽  
High Concentration ◽  
Short Term ◽  
Younger Women ◽  
Dna And Rna ◽  
Poorly Differentiated ◽  
Endometrial Carcinomas ◽  
Dose Dependent

SUMMARY Twenty-five endometrial carcinomas and three non-endometrial carcinomas were studied for the influence of various steroid hormones on the synthesis of DNA and RNA in short-term incubations in vitro. Endometrial carcinomas showed a dose-dependent sensitivity to progesterone in vitro, the response in both nucleic acids sometimes exceeding that of normal endometria. The mean reduction in DNA synthesis was to 46% and in RNA synthesis to 39% of the control values. Poorly differentiated carcinomas showed higher values of DNA synthesis than highly differentiated ones, as did carcinomas from younger women compared with those from older women. The response in vitro to progesterone was not correlated with these factors. Pregnenolone and a synthetic progestogen were less effective in vitro than progesterone. Oestradiol at a high concentration (20 μg/ml) in some cases significantly reduced the synthesis of both nucleic acids, possibly because of a specific 'toxic' action on the cells. No hormonal effects were observed in non-endometrial carcinomas.

THE SYNTHESIS OF DNA AND RNA IN NORMAL HUMAN ENDOMETRIUM IN SHORT-TERM INCUBATION IN VITRO AND ITS RESPONSE TO OESTRADIOL AND PROGESTERONE

1970 ◽  
Vol 48 (1) ◽  
pp. 17-28 ◽  
Author(s):  
S. NORDQVIST
Keyword(s):  
Nucleic Acids ◽  
Dna Synthesis ◽  
Acid Synthesis ◽  
Short Term ◽  
Normal Endometrium ◽  
Dna And Rna ◽  
Progesterone Synthesis ◽  
Normal Human

SUMMARY A method is described for short-term incubations in vitro of normal endometrium for the study of nucleic acid synthesis. Tissue suspensions of specimens obtained at curettage were incubated with and without hormones in a medium consisting of Parker's 199 medium and 20% adult human serum; [3H]thymidine and [14C]uridine were added. The isotope uptake into the nucleic acids was determined and related to the total amount of DNA in each sample. Marked variation in DNA synthesis was noted in endometria obtained at different phases of the menstrual cycle. RNA synthesis varied less. After the addition of progesterone, synthesis of both nucleic acids was reduced. The magnitude of this response varied in different endometria. Thus DNA synthesis in endometria already under strong progesterone influence in vivo (midsecretory phase) was least affected when progesterone was added in vitro.

The Effects of Shock Vancomycin Concentrations on the Formation of Heteroresistance in Staphylococcus aureus

2020 ◽  
Vol 65 (9-10) ◽  
pp. 3-7
Author(s):  
V. V. Gostev ◽  
Yu. V. Sopova ◽  
O. S. Kalinogorskaya ◽  
M. E. Velizhanina ◽  
I. V. Lazareva ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
In Vitro Selection ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
High Concentration ◽  
Short Term ◽  
High Concentrations ◽  
Selection Of ◽  
Selection Of Resistance ◽  
Test Cultures

Glycopeptides are the basis of the treatment of infections caused by MRSA (Methicillin-Resistant Staphylococcus aureus). Previously, it was demonstrated that antibiotic tolerant phenotypes are formed during selection of resistance under the influence of high concentrations of antibiotics. The present study uses a similar in vitro selection model with vancomycin. Clinical isolates of MRSA belonging to genetic lines ST8 and ST239, as well as the MSSA (ATCC29213) strain, were included in the experiment. Test isolates were incubated for five hours in a medium with a high concentration of vancomycin (50 μg/ml). Test cultures were grown on the medium without antibiotic for 18 hours after each exposure. A total of ten exposure cycles were performed. Vancomycin was characterized by bacteriostatic action; the proportion of surviving cells after exposure was 70–100%. After selection, there was a slight increase in the MIC to vancomycin (MIC 2 μg/ml), teicoplanin (MIC 1.5–3 μg/ml) and daptomycin (MIC 0.25–2 μg/ml). According to the results of PAP analysis, all strains showed an increase in the area under curve depending on the concentration of vancomycin after selection, while a heteroresistant phenotype (with PAP/AUC 0.9) was detected in three isolates. All isolates showed walK mutations (T188S, D235N, E261V, V380I, and G223D). Exposure to short-term shock concentrations of vancomycin promotes the formation of heteroresistance in both MRSA and MSSA. Formation of VISA phenotypes is possible during therapy with vancomycin.

scholarly journals Vitamin A and bone formation. Effect of an excess of retinol on bone collagen synthesis in vitro

1985 ◽  
Vol 226 (3) ◽  
pp. 789-795 ◽  
Author(s):  
I Dickson ◽  
J Walls
Keyword(s):  
Bone Formation ◽  
Collagen Synthesis ◽  
Bone Collagen ◽  
Dependent Manner ◽  
Stimulate Bone Resorption ◽  
Dna And Rna ◽  
A Cell ◽  
Dose Dependent ◽  
Bone Collagen Synthesis

The influence of an excess of retinol on bone formation was studied by using cultures of embryonic-chick calvaria. Retinol decreased collagen synthesis in a dose-dependent manner, non-collagenous protein synthesis being relatively unaffected. Collagen synthesis was significantly inhibited after 24 h of culture with retinol and was progressively decreased, compared with control cultures containing no retinol, as the period of culture was increased. The effect of retinol on collagen synthesis could be reversed by incubation of calvaria for further periods in retinol-free medium. Incorporation of [3H]thymidine and [3H]uridine into DNA and RNA respectively was not altered by culturing calvaria with retinol for 22 h. These latter findings, and the selectivity for collagen synthesis, all suggested that the effect observed was not a cell-toxicity phenomenon. The effect of retinol on collagen synthesis by chick calvarial osteoblasts was probably direct and not mediated by osteoclasts, since a negligible number of the latter cells is present in chick calvaria. In cultures of neonatal murine calvaria, which contain many osteoclasts, retinol similarly inhibited synthesis of collagen, but not of non-collagenous protein; the concentrations of retinol necessary to produce the response were similar to those required to stimulate bone resorption in vitro.

Damage by Dichlorvos of Human Lymphocyte DNA

1980 ◽  
Vol 66 (4) ◽  
pp. 425-430 ◽  
Author(s):  
Paolo Perocco ◽  
Angela Fini
Keyword(s):  
Dna Synthesis ◽  
Human Lymphocyte ◽  
Tritiated Thymidine ◽  
Human Lymphocytes ◽  
Ultraviolet Rays ◽  
Thymidine Uptake ◽  
Short Term ◽  
In Vitro System ◽  
Tritiated Thymidine Uptake

The action of dichlorvos (2.2-dichlorovinyldimethyl phosphate) was studied with a short-term in vitro system which utilizes human lymphocytes. The parameters studied were the action exerted by the pesticide on scheduled (semiconservative) and unscheduled (reparative) DNA synthesis measured as tritiated thymidine uptake. The results obtained show that dichlorvos affects semiconservative DNA synthesis, damages human lymphocyte DNA inducing low reparative synthesis, and interferes with DNA repair processes after damage exerted by ultraviolet rays.

Clinical value of in vitro drug sensitivity testing based on short-term effects on dna and rna metabolism in ovarian cancer

1989 ◽  
Vol 41 (3) ◽  
pp. 201-205 ◽  
Author(s):  
S. K. Khoo ◽  
T. Hurst ◽  
M. J. Webb ◽  
G. Dickie ◽  
J. Kearsley ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Drug Sensitivity ◽  
Rna Metabolism ◽  
Short Term ◽  
Clinical Value ◽  
Sensitivity Testing ◽  
Drug Sensitivity Testing ◽  
Dna And Rna ◽  
Short Term Effects

Desoxyribonucleasen in Mäusenieren unter dem Einfluß von Folsäure / On the Action of Folic Acid on Deoxyribonucleases of Mouse Kidney

1971 ◽  
Vol 26 (6) ◽  
pp. 589-594 ◽  
Author(s):  
K. Tempel
Keyword(s):  
Folic Acid ◽  
Dna Synthesis ◽  
Extreme Values ◽  
Dnase I ◽  
Dnase Ii ◽  
X Irradiation ◽  
Acid Deoxyribonuclease ◽  
High Doses ◽  
Dose Dependent

The behaviour of the in vitro-activities of an alkaline and an acid deoxyribonuclease (DNase I and II, resp.), and of an inhibitor of DNase I of the kidney of mice, as well as of the DNA- and protein-content of kidneys and thymus, was studied in about 500 mice 4 hours to 21 days after exposure to folic acid in doses of 60 — 180 mg/kg body-weight.The most important results can be summarized af follows:1. Activity of DNase I decreased and activities of DNase II and of a DNase I-inhibitor increased under the influence of high doses of folic acid. Significant effects were observed 16 — 24 hours after folic acid-injections. Extreme values (80% decrease [DNase I], 180% increase [DNase II, DNase I-inhibitor]) were reached after 2 and 4 days and were dose-dependent. Control values reappeared within 1 — 3 weeks.2. Protein- and DNA-content of the thymus behaved very similarly to DNase I-activity of the kidney.3. The increase of the DNase II-activity of the kidney under the influence of folic acid resulted from enzyme induction. As to the behaviour of DNase I loss of enzyme out of damaged cells and the induction of a DNase I-inhibitor in the kidney must be taken into account.4. In many systems DNase I may control DNA-synthesis. Preliminary studies on the behaviour of folic acid-induced reaction of the kidney, when inhibited by X-irradiation, Actinomycin D, Actidione, or poly (vinylsulfate), suggest that DNase I-inhibitor plays a certain role in combining protein- and DNA-synthesis by inhibiting DNase I.

scholarly journals The Model of D-Galactosamine-Induced Injury of Rat Hepatocytes in Primary Culture

2006 ◽  
Vol 49 (1) ◽  
pp. 59-65 ◽  
Author(s):  
Otto Kučera ◽  
Halka Lotková ◽  
Roman Kanďár ◽  
Renata Héžová ◽  
Vladimíra Mužáková ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Animal Experiments ◽  
Rat Hepatocytes ◽  
Short Term ◽  
Hepatocyte Injury ◽  
Albumin Production ◽  
Potential Activity ◽  
Dose Dependent ◽  
Uridine Nucleotides

D-galactosamine (GalN) is a highly selective hepatotoxin that causes liver damage similar to human viral hepatitis via depletion of uridine nucleotides, which subsequently diminishes synthesis of RNA and proteins. Model of galactosamine hepatotoxicity is frequently used in animal experiments in vitro. The purpose of our study was to establish the model of GalN-induced hepatocyte injury in in vitro conditions using primocultures of rat hepatocytes as an important prerequisite for further experiments in which we would like to study potential hepatoprotective effect of various substances. Rate of hepatocyte injury was evaluated by morphological changes, changes in cell viability, albumin production, mitochondrial membrane potential, activity of mitochondrial dehydrogenases and glutathione content. Marked dose dependent hepatocyte injury was found after 24-hour incubation with GalN. Based on the results we suggest as an optimal model for short-term toxicity test exposure to GalN for 24 hours in dose of 40 mM.

Effects of erythropoietin on cell populations and macromolecular syntheses in foetal mouse erythroid cells

Development ◽  
1973 ◽  
Vol 29 (2) ◽  
pp. 453-472
Author(s):  
John Paul ◽  
David Conkie ◽  
Hugo Burgos
Keyword(s):  
Dna Synthesis ◽  
Mouse Liver ◽  
Rna Synthesis ◽  
Normal Development ◽  
Cell Populations ◽  
Erythroid Cells ◽  
Short Term ◽  
Cell Compartments ◽  
Normal Series

The effects of erythropoietin on maturation of erythroid cells were studied in short-term cultures of foetal mouse liver. Erythropoietin-treated cultures had about 50% more cells than untreated cultures after 24 h. The increase occurred in basophilic, polychromatic and orthochromatic erythroblasts as well as in reticulocytes. A striking feature of erythropoietin-treated cultures was the formation of macro-erythroblasts and macrocytes. Autoradiographic studies indicated that a maturation division was omitted in the formation of these cells and that macrocytes might be derived directly from polychromatic erythroblasts or earlier stages. These studies also indicated that there might be no more than three divisions during the normal development of orthochromatic erythroblasts from proerythroblasts in vitro. The mitotic index of proerythroblasts was raised in erythropoietin-treated cultures within 1–2 h. Moreover, erythropoietin caused a marked elevation of DNA synthesis in proerythroblasts within the first hour of culture but effects on DNA synthesis in other cell compartments were not pronounced. In contrast, an increase in RNA synthesis was noted in proerythroblasts and basophilic and polychromatic erythroblasts; it was greatest in the two former compartments. The stimulation was noticeable, especially in the basophilic compartment, within 2 h but increased progressively throughout the first 5–6 h. Erythropoietin did not induce an increase in total protein synthesis in cells of the normal series but macro-erythroblasts exhibited proportionately more grains.

scholarly journals Nematicidal Activity of Monoterpenoids Against the Root-Knot Nematode Meloidogyne incognita

2010 ◽  
Vol 100 (2) ◽  
pp. 199-203 ◽  
Author(s):  
Sergio Echeverrigaray ◽  
Jucimar Zacaria ◽  
Ricardo Beltrão
Keyword(s):  
Meloidogyne Incognita ◽  
Nematicidal Activity ◽  
Root Knot Nematode ◽  
High Concentration ◽  
Tomato Plants ◽  
Pot Experiments ◽  
Low Concentrations ◽  
Dose Dependent ◽  
Dose Dependent Effect

Nematicidal activity of 22 monoterpenoids were evaluated in vitro and in pot experiments. Twenty of the twenty-two monoterpenoids significantly reduced hatching, and 11 reduced J2 mobility of the root-knot nematode Meloidogyne incognita at a concentration of 250 mg/liter. In general, compounds with hydroxyl and carbonyl groups exhibited higher nematicidal activity than other terpenoids. Borneol, carveol, citral, geraniol, and α-terpineol showed the highest nematicidal activity among the in vitro tested monoterpenoids. These compounds exhibited a dose dependent effect, and drastically reduced eggs hatching and J2 viability at low concentrations. These monoterpenoids, at 100 and 250 mg/kg concentration, diminished root galling of tomato plants in pot experiments. The results suggest that the selected monoterpenoids, and essential oils with high concentration of these compounds, are potential nematicides against Meloidogyne.

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