[Further research on the intracellular "pool" of alpha-globin in beta-thalassemia]

The autoimmune diseases result from inappropriate responses of the immune system to self antigens. The etiology of autoimmune diseases remains largely unknown but candidate etiologic factors include genetic abnormalities and infections. Although there are considerable data supporting the role of infections in a variety of autoimmune diseases, this role has been unequivocally established in only a few autoimmune diseases. The difficulty in establishing the infectious etiology of autoimmune diseases stems from several factors such as the heterogeneity of clinical manifestations in individual autoimmune diseases and the time interval between infection and autoimmune disease. The data on this association derive from clinical observations, epidemiological studies and research using laboratory techniques, protein sequence database screening and animal models. Infectious agents can cause autoimmune diseases by different mechanisms, which fall into two categories: antigen specific in which pathogen products or elements have a central role e.g. superantigens or epitope (molecular) mimicry, and antigen non-specific in which the pathogen provides the appropriate inflammatory setting for "bystander activation". The most important mechanisms are molecular mimicry and superantigens. As far as molecular mimicry is concerned the recent data on the degeneracy of T cell recognition shifted the focus from searching for linear sequence homology to looking for similarity of antigenic surfaces. Special mention has to be made to retroviruses as they have some unique means of inducing autoimmunity.

Significance of the changes in the circulating lymphoid cells in Hodgkin's disease

The lymphoid cell population in the peripheral blood in Hodgkin's disease differs from normal blood in three ways. Firstly, the number of large lymphoid cells actively synthesizing deoxyribonucleic acid is increased; secondly, the number of medium-sized lymphoid cells with intensely basophilic cytoplasm is increased; and, thirdly, occasional plasma cells are seen. These changes are related to the activity but not to the stage of the disease.Similar changes are found under conditions of known antigenic challenge-that is, in infections, and after immunization, and in rheumatoid arthritis and systemic lupus erythematosus.

Ultrastructural alterations of tissue cultures infected with a pathogenic porcine adenovirus

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Pathogenicity of staphylococci: with special reference to the persitence of infection in mice

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Pneumonia in rats due to infection with Corynebacterium kutscheri

A spontaneous outbreak of infection with C. kutscheri occurred in a commercial rat colony. Clinical signs were emaciation, hyperpnea, nasal and ocular encrustations, humping of the back, sluggishness, and roughness of the hair coat. Caseopurulent foci, 1 to 15 mm in diameter, occurred, primarily in the lungs and occasionally in the liver, kidneys, and subcutis. Corynebacterium kutscheri was consistently isolated from organs with lesions. Typical lesions were experimentally reproduced in some, but not all, rats inoculated by the intranasal, intraperitoneal, and oral routes with cultures of C. kutscheri.