0000000000002557
AUTHOR
A. Sinatra
On the hemagglutinating and hemolytic activity of measles virus variants.
The hemagglutinating (HA) and hemolytic (HL) activity of two measles virus variants, differing with regard to type of CPE and other characteristics, have been investigated.
Neurotropism in newborn hamsters of plaque purified measles virus clones
Three plaque purified measles virus clones displayed a different neurotropism in newborn hamsters.
Studies on a measles virus variant inducing persistent infections in cultured cells
Attempts were made to characterized by a plaque assay two variants of the Edmonston strain of measles virus and to obtain plaque purified virus populations. The UP non-cytocidal variant, in all the examined cell systems, mainly produced small but also large plaques; the DP cytocidal variant always large plaques. Three clones, UP-SP4, UP-LP4 and DP-LP4, were derived by plaque purfication respectively of the UP small plaque, UP large plaque and DP large plaque forming particles. The virus populations of the clones could be distinguished by some other biological and physical characters: cytopathic effect in roller tube cultures, growth potential in HeLa cells, thermal stability at 45 degrees C…
A comparative assay of epidemiological markers for Acinetobacter strains isolated in a hospital.
Summary A comparative assay for epidemiological evaluation of three different Acinetobacter typing procedures, i.e. biotyping, phagetyping, and the analysis of the bacterial envelope protein profiles, was carried out using sixty-four multiresistant Acinetobacter strains isolated from clinical specimens. The antibiotic susceptibility of the strains was also considered. After genospecies identification, biotyping allowed the recognition of a relatively large and long-lasting presence, at an Intenive Therapy Unit, of two A. baumannii biotypes. Phage-typing and the analysis of the susceptibility to antibiotics allowed for the differentiation of strains belonging to different genospecies and bio…
Latent measles virus infection in Vero cells depending on a temperature-sensitive phenomenon.
A latent infection by measles virus in a line of Vero cells could be maintained only at 37 degrees C. The conditions of temperature nonpermissiveness were associated with some block in virus production and/or release and with the establishment of an autointerference phenomenon. Reduction of the incubation temperature to 33.5 degrees C induced a rather rapid transition from the latent to a lytical infection with a recue of virus. The rescued virus exhibited a restricted capacity to grow at 37 degrees C.
Infections caused by Pseudomonas aeruginosa: relatively frequent isolation of serogroup 12 from clinical specimens.
Serological typing of P. aeruginosa is the most simple and reliable procedure recommended for ≪ in-house ≫ investigations and for studies of suspected outbreaks of infection by this microorganism. It is also a useful procedure in order to know serotype prevalence in a definite geografical area and to obtain indications about the more appropriate composition of polivalent anti-Pseudomonas vaccines. In the present report, we describe the relatively high frequency of isolation of serogroup 12 from patients in Palermo, Italy. Serogroup 12 is very rare in north-Europe and in the USA, and, as a consequence, it is not included in some vaccine preparations. In Palermo, strains belonging to this ser…