Albert M. Jonas

Transmissible Murine Colonic Hyperplasia

After exposure to a variant of Citrobacter freundii, suckling and adult mice developed transmissible murine colonic hyperplasia of the same degree of severity. Mucosal hyperplasia was most severe 2 to 3 weeks after inoculation and then regressed. Suckling mice had a high mortality because of secondary inflammatory and erosive changes. Severe hyperplasia was characterized by mitotic activity along the entire crypt column and surface mucosa.

Pathogenesis of Sialodacryoadenitis in Gnotobiotic Rats

The pathogenesis of sialodacryoadenitis was studied in gnotobiotic CD rats inoculated intranasally with the causal virus. Virus replication was detected sequentially in the nasopharynx, tracheobronchial tree, cervical lymph nodes, submaxillary and parotid salivary glands, exorbital gland, and Harderian gland. Acute rhinitis appeared within 2 days after inoculation, and salivary glands had lesions in 4 days. Early changes in salivary and exorbital glands were characterized by necrosis of ductal epithelium, which rapidly progressed to widespread acinar necrosis, marked inflammation, edema and total effacement of glandular architecture. Harderian glands also had massive necrosis of tubuloalveolar units. Repair in all glands was characterized by marked squamous metaplasia of ducts. Neutralizing and complement-fixing antibodies were detected in 7 days, and there was a concomitant decrease in tissue-virus titers. There was no detectable evidence for hematogenous spread of virus or for retrograde infection by way of major salivary ducts.

Characterization of the Virus of Sialodacryoadenitis of Rats: A Member of the Coronavirus Group

Abstract The virus that causes sialodacryoadenitis in rats has been isolated in mice and in primary cultures of rat-kidney cells and has been characterized as a heat-labile RNA virus that is sensitive to lipid solvents and is relatively stable at pH 3.0. This virus is antigenically related to the virus of hepatitis in mice and to coronavirus of rats. The range of hosts of this agent appears to be narrow. On the basis of available biologic characteristics, it has been placed in the coronavirus group.

Naturally occurring lethal parvovirus infection of juvenile and young-adult rats.

A lethal disease characterized by hemorrhage and necrosis of the brain, testes, and epididymides developed in young adult rats housed in specific pathogen free quarters. Morphological, virological, and serological investigations of the outbreak indicated that the probable causative agent was rat virus (Kilham), a common parvovirus of rats that usually Induces persistent, asymptomatic infection in adult rats.

The Neuropathology of Globoid-Cell Leucodystrophy in the Dog

SummaryNeuropathological studies of two young dogs with globoid cell leucodystrophy revealed changes similar to those reported in human cases of this condition. There was bilaterally symmetrical loss of myelin staining in large regions of white matter in brain and spinal cold. This was accompanied by many globoid cells, large apparently phagocytic cells, most prominent around blood vessels in regions of altered myelin. These cells were PAS positive, non-metachromatic, and stained gray with Sudan black B. The PAS reaction was only slightly reduced by lipid solvents. Also seen in these regions were large numbers of hypertrophied astrocytes. In severely involved regions axons were reduced in number. Diffuse ventricular dilatation was noted in one animal.ZusammenfassungNeuropathologische Untersuchungen bei zwei jungen Hunden mit Leukodystrophie vom Globoidzell-Typ ergaben ähnliche Veränderungen wie bei Humanfällen dieser Erkrankung. Es bestanden symmetrische Entmarkungen in weiten Gebieten der weißen Hirn-und Rückenmarkssubstanz begleitet von zahlreichen Globoidzellen als offenbar großen Phagocytenzellen, vorwiegend um Blutgefäße in den betroffenen Markregionen. Diese Zellen waren PAS-positiv, nicht-metachromatisch und zeigten Graufärbung mit Sudanschwarz B. Die PAS-Reaktion wurde durch Lipidlösungsmittel nur leicht abgeschwächt. Daneben fanden sich in den betroffenen Arealen zahlreiche hyperplastische Astrocyten. In schwer betroffenen Gebieten waren die Axone numerisch reduziert. Bei einem Tier bestand eine diffuse Ventrikelerweiterung.