Many methods are available for determining the sensitivity of M. tuberculosis to various chemotherapeutic agents. These may be divided broadly into three groups. In the first group the streptomycin is incorporated into solid media, such as that of Herrold (1931) or of Lowenstein (1930) and Jensen (1932) (Pyle, 1947; Johnson, 1950; Youmans, Ibrahim, Sweany, and Sweany, 1950; Tinne and Henderson,...

Bang and Ellerman, and later Peyton Rous, reported the first identification of transmissible cancer-causing agents, which later turned out to be avian retroviruses. Today avian retroviruses are important models for study of retrovirus replication and pathogenesis, and also important pathogens of domestic fowl. Here we describe the use of RNA interference (RNAi) in live chick embryos to block re...

Research in anatomy, embryology, and developmental biology has largely relied on the use of model organisms. In order to study development in live embryos model organisms, such as the chicken, are often used. The chicken is an excellent model organism due to its low cost and minimal maintenance, however they present observational challenges because they are enclosed in an opaque eggshell. In or...

Temperature-sensitive mutants of Sindbis virus were employed to investigate the nature of the viral event(s) which induces chick-embryo cells to produce interferon. Chick embryo cells induced by the parental heat-resistant strain of Sindbis virus produced essentially equal amounts of interferon at 29 and 42 C. An RNA(-) and three RNA(+) strains [temperature-sensitive mutants unable (RNA(-)) and...

The effects of chloroquine on the growth and morphology of fibroblasts in tissue culture, and in vivo granulomas were investigated. As the result, the drug was shown to have a potent action to inhibit fibroblast growth, which has led to a possibility of its clinical use to patients with malignant tumors. ∗PMID: 14165348 [PubMed OLDMEDLINE] Copyright c ©OKAYAMA UNIVERSITY MEDICAL SCHOOL Acta Med...

Infection of stationary chick embryo fibroblasts by reticuloendotheliosis virus (REV) is sensitive to cytosine arabinoside, an inhibitor of DNA synthesis. Furthermore, the majority of the nucleic acid sequences contained in the REV genome can be detected in infected cells in the form of DNA by RNA-DNA hybridization techniques. A small portion (ca. 5%) of the REV-specific sequences can be detect...

These results show that primary chick embryo cells in culture release a particle bound RNA dependent DNA polymerase into the culture fluid. The enzyme is also found in the allantoic fluid of embryonated chicken eggs. This phenomenon is not restricted to the chicken system because primary quail embryo cells which are not known to express the so far known endogenous viruses release a particle bou...

An efficient in vitro screening method for antitumor and/or antitumorigenic substances was established. The method is based on determining inhibitory effect of a compound on an RSV-induced tumorigenic process and the growth of the established tumor cells in a single assay system in the presence of normal cells. These effects were determined by inhibition of focus formation in a culture of chick...

Using PH]thymidine incorporation into DNA of human lymphocytes in culture, we have shown that human serum contains an ultrafiltrable factor(s) that sensitizes the activation of lymphocytes by phytohaemagglutinin. This (these) factor(s) can replace either human serum or foetal calf serum in the culture. In addition, it permits the expression, and therefore the assay, of human somatomedin A pepti...