Effect of seasonal variation on the acute toxicity of cyclophosphamide in the Chinese hamster (Cricetulus griseus) and the mouse under laboratory conditions

Summary The acute toxicity of cyclophosphamide, studied orally in chinese hamsters and intravenously in Tif: MAGf (SPF) mice, showed seasonal variation in Chinese hamsters but not in mice.Acknowledgement. I thank Mr R. Gebus for skilful technical and Mr A.P. Grieve for statistical assistance.     

The karyotype ofDusicyon griseus (Carnivora canidae)

Resumen Se describe el cariotipo deDusicyon griseus el cual posee una fórmula cromosómica de2N=74 y un número fundamental (NF) de 76. Por otra parte, se entrega por primera vez información acerca de los cromosomas sexuales de una especie de este género. Desde este punto de vista llama la atención que el cromosomay es un microcromosoma.     

Establishment of normal diploid and malignant heteroploid cell lines from non-treated and benzo(a)pyrene treated hamster embryo cell cultures

Summary Two normal diploid control cell lines and a heteroploid malignant transformed cell line from B(a) P treated hamster embryo cell cultures were established. The 14-month-old B(a)P transformed cell line grew 8-times faster than the 20-month-old control cell line. The control cell line showed normal diploid chromosome complement in 93% cells and heteroploidy in 7% cells while B(a)P treated line showed 83% heteroploid cells and only 17% diploid cells. This is the first report on the establishment of diploid hamster cell cultures grown for extended period. Acknowledgments. This work was supported by the French Ministry of Quality of Life, by the Institut National de la Santé et Recherche Médicale, by the S.E.I.T.A. and by Contract No. 12-14-7001-297 of the Agricultural Research Service, U.S. Dept. of Agriculture, Administered by the Athens, Georgia Area, Richard B. Russell Agricultural Research Center, Athens, Georgia 30604, USA. We thank Mr.B. R. Sharma, Mr.E. J. Radin, Dr.R. Hakim and Dr.Ved Brat for their help during this work.     

Establishment of normal diploid and malignant heteroploid cell lines from non-treated and benzo(a)pyrene treated hamster embryo cell cultures.

Two normal diploid control cell lines and a heteroploid malignant transformed cell line from B(a)P treated hamster embryo cell cultures were established. The 14-month-old B(a)P transformed cell line grew 8-times faster than the 20-month-old control cell line. The control cell line showed normal diploid chromosome complement in 93% cells and heteroploidy in 7% cells while B(a)P treated line showed 83% heteroploid cells and only 17% diploid cells. This is the first report on the establishment of diploid hamster cell cultures grown for extended period.     

Induced radiation resistance in cell cultures of Chinese hamster cells: induction and manner of resistance (author's transl)]

Mutations-induction followed by selection is a suitable method for developing a cell line with resistance to low doses of X-rays. In comparison with the original cell line, the derived resistant line is characterized by an enhanced variability of the chromosome number, and no higher level of cellular repair, limited to the two repair types described.     

Formation of plantlets from callus cultures of ginseng (Panax ginseng)

Summary From callus cultures ofPanax ginseng C.A. Mayer, shoots and roots were systematically formed at a high rate (in all flasks) under optimal culture conditions. The chemical constituents and the morphological structures of the differentiated plantlets closely resembled those of the native plants.Part 44 in the series Studies on Plant Tissue Culture. For Part 43 see Yoshikawa, T., and Furuya, T., Planta med. (1985) 110.     

The isolation of a phytotoxin from cultures ofDidymella applanata (Niessl)sacc

Zusammenfassung Die Isolierung eines phytotoxischen Stoffes aus der Kulturflüssigkeit vonDidymella applanata (Niessl)sacc., der eine Krankheit bei Himbeeren verursacht, wird beschrieben. Die Symptome dieser Krankheit und die Züchtungsbedingungen für den Mikroorganismus und die Testpflanzen werden angegeben. Das Toxin dürfte ein Oligosaccharid sein.     

Lymphocyte survival and macrophage growth in long term in vitro leucocyte cultures

Zusammenfassung Unterschwellige Dosen von Phytohämagglutinin verlängern die Lebensdauer von Lymphozyten in menschlichen Zellkulturen, vermindern die Zahl der Makrophagen in der Kultur und erhöhen die Zahl der transformationsfähigen Lymphozyten.     

Decontamination of pleuropneumonia-like organism (PPLO) infected tissue cultures

Zusammenfassung PPLO-verunreinigte Zellkulturen wurden mit Novobiocin® PPLO-eliminierend behandelt. Nach dem Empfindlichkeitstest folgte die Bestimmung der Toxizität dieses Antibiotikums für Gewebekulturzellen. Anschliessend wurden maximale, für Zellen nichttoxische Konzentrationen verwendet. Die entwickelte Methode ermöglicht, den Wirkungsgrad dieser antibiotischen Behandlung zu bestimmen.     

Propagation of mouse hepatitis virus (MHV-3) in monolayer cell cultures from liver of new-born mice

Riassunto È stata provata la possibilità di coltivare MHV-3 in colture monostrato di cellule di fegato di topo neonato ottenute per tripsinizzazione. Per questo tipo di coltura è indispensabile l'aggiunta alla tripsina di metilcellulosa e di estratto embrionale di pollo al terreno di coltura. MHV-3 si moltiplica attivamente in queste colture, raggiungendo elevate concentrazioni nel liquido di coltura e producendo effetto citopatico.     

Graphs in cultures (II): A study in ethnomathematics

Western culture is but one of several with an interest in continuous tracing of figures. This paper discusses and analyzes that interest as it is evidenced in Africa among the Bushoong and Tshokwe. Included are figures, statements about the cultural context, and associated geometric and topological ideas. Emphasis is on the structure of the figures and also, where possible, processes of construction are elaborated.