RESUMEN
Storage and resuscitation of MDCC-MSB1 cells, most commonly used for the propagation of chicken anemia virus was studied. Cells were frozen slowly in RPMI medium 1640 with 10% or 20% fetal bovine serum and 20% dimethyl sulfoxide, held at -70 C overnight, and placed into liquid nitrogen the next day. After 1 mo, 91% to 100% resuscitation rates were obtained, while cells that were frozen fast (directly transferred into liquid nitrogen) could not be resuscitated.
Asunto(s)
Técnicas de Cultivo de Célula/métodos , Virus de la Anemia del Pollo/crecimiento & desarrollo , Criopreservación/métodos , Animales , Sangre , Bovinos , Línea Celular , Supervivencia Celular , Pollos , Medios de CultivoRESUMEN
Is gardening a health hazard? Legionella longbeachae, a potential cause of pneumonia, has been found in Australian potting media. However, further research is needed to determine its clinical relevance in this situation. This did not stop the popular media linking two deaths from Legionella infection in Queensland to potting mix exposure.
Asunto(s)
Enfermedades de los Trabajadores Agrícolas/microbiología , Legionella/aislamiento & purificación , Legionelosis/microbiología , Neumonía Bacteriana/microbiología , Microbiología del Suelo , Anciano , Enfermedades de los Trabajadores Agrícolas/inmunología , Anticuerpos Antibacterianos/sangre , Australia/epidemiología , Resultado Fatal , Miedo , Humanos , Legionella/clasificación , Legionella/inmunología , Legionelosis/epidemiología , Legionelosis/inmunología , Legionelosis/psicología , Persona de Mediana Edad , Neumonía Bacteriana/epidemiologíaRESUMEN
Vero cells were infected by Kunjin virus and radiolabelled in the presence of the leucine analogue, threo-beta-hydroxy-DL-leucine (THL). This analogue is known to prevent preprotein processing in cell-free systems when incorporated into signal peptides. Novel Kunjin virus-specified proteins were detected, namely gp140, p120 and gp92; the designations for the proteins indicate their approximate Mr X 10(-3) and whether they are glycosylated. The glycoproteins gp140 and gp92 were observed in cells labelled with [3H]mannose and bound to concanavalin A. Limited proteolytic digestion of gp140, gp92 and gp66 (related to the envelope protein E), and tryptic peptide mapping of these three glycoproteins and p120 indicated that all four were closely related. The glycoproteins gp140 and gp92 were also detected in cells infected by West Nile virus radiolabelled in the presence of THL. Other effects of THL in Kunjin virus-infected cells were a reduction in the incorporation of radioactive amino acids or mannose, a decrease in the yield of haemagglutinin and infectious virus, an inhibition of processing of gp66 to gp53 and an apparent inhibition of synthesis of P98 and P71. We suggest possible explanations for the THL-induced changes in infected cells based on recent models proposed for the synthesis of the yellow fever and West Nile viral proteins.