scholarly journals LATENT VIRAL INFECTION OF CELLS IN TISSUE CULTURE

1956 ◽  
Vol 103 (6) ◽  
pp. 765-775 ◽  
Author(s):  
Karl M. Johnson ◽  
Herbert R. Morgan
Keyword(s):  
Amino Acids ◽  
Viral Infection ◽  
Synthetic Medium ◽  
Water Soluble ◽  
Virus Growth ◽  
Viral Multiplication ◽  
Minimum Number ◽  
Synthetic Media ◽  
Stimulation Of

When chick embryo tissues cultivated for 13 days in Hanks's balanced salt solution (BSS) were infected with psittacosis virus (6BC), they did not support active viral multiplication until synthetic medium 199 of Parker (3) was added. By testing various combinations of the substances in this and other synthetic media, it was found that the minimum number of compounds required to effectively stimulate virus growth in the presence of BSS comprised the amino acids and water-soluble vitamins found in medium 199. Addition of either amino acids or water-soluble vitamins alone to BSS resulted in only slight stimulation of viral proliferation. Many constituents of the synthetic media were found not to be essential to the stimulation of viral multiplication. The following substances added to a medium containing amino acids and water-soluble vitamins in BSS failed to increase the quantity of virus produced: diphosphopyridine nucleotide (DPN), triphosphopyridine nucleotide (TPN), coenzyme A, the fat-soluble vitamins, ribose sugars, and three biological reducing agents: cysteine, glutathione, and ascorbic acid. Among other substances that proved to be not essential a group of purines and pyrimidines present in medium 199 were found to be probably toxic to cells in the concentrations used, since virus titers were lower in media containing these compounds than in those from which they were absent. A change in the nutritional status of these cells involving amino acids and water-soluble vitamins has thus permitted to transform a latent, undetectable viral infection to an inactive infection in vitro.

scholarly journals LATENT VIRAL INFECTION OF CELLS IN TISSUE CULTURE

1958 ◽  
Vol 108 (5) ◽  
pp. 617-630 ◽  
Author(s):  
John P. Bader ◽  
Herbert R. Morgan
Keyword(s):  
Amino Acids ◽  
Viral Infections ◽  
Synthetic Medium ◽  
Water Soluble ◽  
Inorganic Salts ◽  
Virus Propagation ◽  
Virus Growth ◽  
Latent Viral Infection ◽  
Complete Synthetic Medium ◽  
Stimulation Of

Mouse fibroblasts (L cells) fail to support the growth of psittacosis virus (6BC strain) if they are maintained on a medium containing only inorganic salts and glucose for 2 days prior to infection. Virus propagation can be stimulated by the addition of a synthetic medium containing amino acids, water-soluble vitamins, glutamine, glucose, and inorganic salts. By omitting single amino acids from the complete synthetic medium, tyrosine, threonine, methionine, isoleucine, phenylalanine, tryptophan, leucine, valine, and cysteine or cystine were found to be essential for stimulation, while lysine, arginine, histidine, hydroxyproline, proline, glutamic acid, aspartic acid, serine, alanine, and glycine were not essential. The cells on deficient media showed varying degrees of degenerative changes, but there was little correlation between ability to support psittacosis virus growth and morphologic condition of the cells. Glucose is also an essential component of the medium for viral growth, but the absence of glutamine had no effect on stimulation of virus propagation. L cell cultures maintained on media deficient in phenylalanine or tryptophan for 2 days before infection were also found to be incapable of supporting virus growth. The implications of this study in latent viral infections are discussed.

scholarly journals Perspectives approach to the assessment of the quality of the vaccine plague live in terms of immunogenicity. Epidemiology and Vaccinal Prevention

2019 ◽  
Vol 18 (1) ◽  
pp. 50-54
Author(s):  
S. E. Gostischeva ◽  
N. V. Abzaeva ◽  
E. L. Rakitina ◽  
D. G. Ponomarenko ◽  
M. V. Kostuchenko ◽  
...  
Keyword(s):  
Specific Antigen ◽  
Water Soluble ◽  
Control Group ◽  
In Vitro Tests ◽  
Laboratory Mice ◽  
Early Activation ◽  
High Degree ◽  
Stimulation Of

Research objective–studying of a possibility of application antigen – stimulated cellular in vitro tests and technology of the cytometric analysis for control of immunogene activity of batches of vaccine plague live.Materials and methods.As biomodels used white laboratory mice, immunized commercial medicine of vaccine of the plague NIIEG line, live from a strain of Yersinia pestis EV, in doses – 8 х 102, 4 х 103, 2 х 104 and 1 х 105 of living microbic cells. Blood for a research was taken from intact mice and on 7, 14 and 21 days after immunization. The intensity of an antigenreaktivnost of lymphocytes was defined in cellular in vitro tests, analyzing a marker of early activation (CD45+CD3+CD25+) of lymphocytes with use of the monoclonal antibodies conjugated from fluorokhroma. As specific antigen used a complex of water-soluble antigens of a plague microbe.Results.As a result of a research it is shown that at the animals vaccinated by doses 4 х 103 – 1 х 105 living microbic cells, the highest level of an expression activation marker lymphocytes at anti-gene stimulation of in vitro is registered on 14 days after immunization, at the same time the quantity of CD25 – positive lymphocytes are on average 6.8 times higher, than in control group. High degree of direct link (coefficient of correlation of r = 1,000) quantities of the survived animals with increase in level of lymphocytes, expressiruyushchy markers of early activation – CD25 is established.Conclusions.The offered technique can be used as the additional test when studying degree of immunogenicity of new (kandidatny) vaccines against plague.

scholarly journals On the Nitrogen Nutrition of Silage Strains of Lactic Acid Bacteria

1966 ◽  
Vol 19 (1) ◽  
pp. 105 ◽  
Author(s):  
CJ Brady
Keyword(s):  
Amino Acids ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Free Amino Acids ◽  
Free Amino ◽  
Nitrogen Nutrition ◽  
Synthetic Medium ◽  
Post Harvest ◽  
Synthetic Media ◽  
Time Of Harvest

Consideration is given to the adequacy of the free amino acids in plant juices at the time of harvest as nitrogen substrate for strains of lactic acid bacteria isolated from silage. The requirements of several strains of the bacteria for free amino acids in synthetic media were compared with the concentration of these acids in the liquid phase of plants at the time of harvest; this comparison suggested that several amino acids, and particulady lysine, may at times be rate.limiting. Ethanolic extracts of plants, sampled before and after a period of post-harvest wilting, were assayed as nitrogen substrates for the bacteria. A marked response to additions of lysine, some response to arginine, and evidence of deficiency of other acids were noted. The importance of post-harvest proteolysis to the amino acid nutrition of the bacteria in the silage environment is discussed. Certain fractions of the plant extracts were found to promote early growth of the bacteria in the synthetic medium, and the distribution of this activity in different fractions is described.

scholarly journals In vitro assessment of the capacity of certain mycotoxin binders to adsorb some amino acids and water-soluble vitamins

2020 ◽  
Vol 103 (4) ◽  
pp. 3125-3132
Author(s):  
A. Kihal ◽  
M. Rodriguez-Prado ◽  
C. Godoy ◽  
C. Cristofol ◽  
S. Calsamiglia
Keyword(s):  
Amino Acids ◽  
Water Soluble ◽  
In Vitro Assessment

THE EFFECT OF GROWTH HORMONE AND OF CORTISOL ON THE RESPONSE OF ISOLATED RAT DIAPHRAGM TO THE STIMULATING EFFECT OF INSULIN ON GLUCOSE UPTAKE AND ON INCORPORATION OF AMINO ACIDS INTO PROTEIN

1959 ◽  
Vol 18 (4) ◽  
pp. 395-408 ◽  
Author(s):  
K. L. MANCHESTER ◽  
P. J. RANDLE ◽  
F. G. YOUNG
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Protein Synthesis ◽  
Glucose Uptake ◽  
Carbohydrate Metabolism ◽  
Rat Diaphragm ◽  
Pituitary Growth Hormone ◽  
Isolated Rat ◽  
Stimulation Of

SUMMARY 1. The effect of hypophysectomy, or of adrenalectomy, and injection of pituitary growth hormone (GH) or of cortisol, on the uptake of glucose and the incorporation of glycine into protein by isolated rat diaphragm, and the effect of the addition of insulin in vitro on these processes, has been studied. 2. Both hypophysectomy and adrenalectomy raised the uptake of glucose by isolated diaphragm, while treatment of the intact or of the hypophysectomized rat with GH, or of the intact or of the adrenalectomized rat with cortisol, depressed it. Although hypophysectomy and adrenalectomy did not influence the additional glucose uptake induced by 200 mu./ml. of insulin in vitro, both these operations enhanced the effect of 0·1–1·0 mu./ml. of insulin on glucose uptake by diaphragm in vitro. Treatment of the rat with GH or cortisol diminished the rise in glucose uptake of diaphragm induced by 0·1–1·0 mu./ml. insulin. 3. Hypophysectomy depressed, and administration of GH to the intact or hypophysectomized rat raised, the incorporation of glycine into protein of the isolated diaphragm, but neither of these operations altered the magnitude of the stimulation of incorporation induced by 1·0 mu./ml. insulin. 4. Adrenalectomy raised, and administration of cortisol to the intact or adrenalectomized rat depressed, the incorporation of glycine into protein of the isolated diaphragm; adrenalectomy enhanced, the injection of cortisol diminished, the effect of 1·0 mu./ml. insulin on these processes. 5. The possibility that GH directs insulin towards the stimulation of protein synthesis, in part by restraining the action of insulin on carbohydrate metabolism, is discussed.

scholarly journals Expression Profiling of Virulence and Pathogenicity Genes of Xanthomonas axonopodis pv. citri

2005 ◽  
Vol 187 (3) ◽  
pp. 1201-1205 ◽  
Author(s):  
Gustavo Astua-Monge ◽  
Juliana Freitas-Astua ◽  
Gisele Bacocina ◽  
Juliana Roncoletta ◽  
Sérgio A. Carvalho ◽  
...  
Keyword(s):  
Data Analysis ◽  
Expression Profiling ◽  
Synthetic Medium ◽  
In Vitro System ◽  
Xanthomonas Axonopodis ◽  
Transcriptional Alterations ◽  
Synthetic Media ◽  
Media Data ◽  
Dna Macroarrays

ABSTRACT DNA macroarrays of 279 genes of Xanthomonas axonopodis pv. citri potentially associated with pathogenicity and virulence were used to compare the transcriptional alterations of this bacterium in response to two synthetic media. Data analysis indicated that 31 genes were up-regulated by synthetic medium XVM2, while only 7 genes were repressed. The results suggest that XVM2 could be used as an in vitro system to identify candidate genes involved in pathogenesis of X. axonopodis pv. citri.

scholarly journals Investigation of the Immunostimulatory Properties of Oxihumate

2003 ◽  
Vol 58 (3-4) ◽  
pp. 263-267 ◽  
Author(s):  
Gisela Käthe Jooné ◽  
Johan Dekker ◽  
Constance Elizabeth Jansen van Rensburg
Keyword(s):  
Proliferative Response ◽  
Bituminous Coal ◽  
Ex Vivo ◽  
Human Lymphocytes ◽  
Water Soluble ◽  
Hiv Positive ◽  
Wet Oxidation ◽  
Mechanistic Studies ◽  
Stimulation Of

A unique process has been developed to convert bituminous coal by controlled wet oxidation followed by base treatment to a water-soluble humate called oxihumate. The effects of oxihumate on the proliferative response of lymphocytes has been studied in vitro and ex vivo. Oxihumate increased the proliferative response of phytohaemagglutinin-stimulated human lymphocytes, from a concentration of 20 μg/ml and upwards. This response was even more striking in the case of lymphocytes from HIV-infected patients and was not limited to the in vitro setting since similar effects were observed ex vivo following administration of a nontoxic dosage of 4 g oxihumate per day to HIV-positive individuals for two weeks. Mechanistic studies revealed that stimulation of the proliferative response of lymphocytes by oxihumate is associated with an increased production of IL-2, as well as expression of the IL-2 receptor in the setting of decreased production of IL-10. Oxihumate therefore holds promise for the treatment of immunocompromized patients.

scholarly journals Amino acid requirement for the growth-hormone stimulation of incorporation of precursors into protein and nucleic acids of liver slices

1970 ◽  
Vol 119 (4) ◽  
pp. 629-634 ◽  
Author(s):  
M. J. Clemens ◽  
A. Korner
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Protein Synthesis ◽  
Amino Acid ◽  
Mechanism Of Action ◽  
Plasma Concentrations ◽  
Liver Slices ◽  
Hypophysectomized Rats ◽  
Stimulation Of

1. Incorporation of [14C]leucine into protein in rat liver slices, incubated in vitro, increased as the concentration of unlabelled amino acids in the incubation medium was raised. A plateau of incorporation was reached when the amino acid concentration was 6 times that present in rat plasma. Labelling of RNA by [3H]orotic acid was not stimulated by increased amino acid concentration in the incubation medium. 2. When amino acids were absent from the medium, or present at the normal plasma concentrations, no effect of added growth hormone on labelling of protein or RNA by precursor was observed. 3. When amino acids were present in the medium at 6 times the normal plasma concentrations addition of growth hormone stimulated incorporation of the appropriate labelled precursor into protein of liver slices from normal rats by 31%, and into RNA by 22%. A significant effect was seen at a hormone concentration as low as 10ng/ml. 4. Under the same conditions addition of growth hormone also stimulated protein labelling in liver slices from hypophysectomized rats. Tissue from hypophysectomized rats previously treated with growth hormone did not respond to growth hormone in vitro. 5. No effect of the hormone on the rate or extent of uptake of radioactive precursors into acid-soluble pools was found. 6. Cycloheximide completely abolished the hormone-induced increment in labelling of both RNA and protein. 7. It was concluded that, in the presence of an abundant amino acid supply, growth hormone can stimulate the synthesis of protein in rat liver slices by a mechanism that is more sensitive to cycloheximide than is the basal protein synthesis. The stimulation of RNA labelling observed in the presence of growth hormone may be a secondary consequence of the hormonal effect on protein synthesis. 8. The mechanism of action of growth hormone on liver protein synthesis in vitro was concluded to be similar to its mechanism of action in vivo.

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