Duration of immunity in dogs after vaccination or naturally acquired infection.

This paper reviews current scientific information about the duration of immunity induced in dogs by infection or vaccination. It describes the shortcomings of the methods used to measure the immune responses of dogs, and explains the need for basic studies on the nature of protective humoral and cellular responses, and standardised assays for the long-term duration of immunity to pathogens other than rabies. The information is inadequate to warrant uniform recommendations on the ideal intervals for vaccination; each vaccine must be evaluated on the basis of its own merits and the characteristics of the disease it is intended to guard against.

Duration of immunity in cats after vaccination or naturally acquired infection.

The necessity for cats to be vaccinated annually against common pathogens has been questioned because sarcomas have infrequently been reported at the injection site. However, with few exceptions, the duration of immunity induced by vaccination or infection is uncertain, and there may therefore be a risk associated with a decision not to revaccinate. This article reviews the information available about the duration of immunity induced by vaccination or infection in cats, and reveals many shortcomings that make blanket recommendations impossible. Each vaccine must be considered individually.

Neonatal tolerant immunity for vaccination against autoimmunity.

Autoimmunity arises when the immune system no longer tolerates self and precipitates lymphocyte reactivity against our own antigens. Although the developing T cell repertoire is constantly purging, self-recognition events do exist when such tight control is evaded and autoreactive lymphocytes escape the thymus (the sites of T cell development) and migrate to the periphery. Upon activation these autoreactive cells may exert aggressive behavior toward one's own tissues and organs leading to autoimmune disease. Multiple sclerosis, Rheumatoid arthritis, and type I diabetes are autoimmune diseases mediated by autoreactive T cells. A logical approach to prevent such autoimmunity would be to reprogram those lymphocytes to tolerate the self antigen. Injection of antigen at the neonatal stage promotes a state of tolerance such that successive encounter with antigen does not precipitate aggressive reactions. The mechanism underlying neonatal tolerance involves priming of T cells whose effector functions do not cause inflammatory reactions upon recognition of antigen but rather induce protective immunity. This form of tolerant immunity provides an attractive strategy for vaccination against autoimmunity. Herein, it is shown that neonatal exposure to a self-peptide-immunoglobulin chimera drives a tolerant immunity toward the self-peptide and protects against the autoimmune disease, experimental allergic encephalomyelitis.

Titanium carbide, nitride and carbonitrides: a 13C, 14N, 15N and 47,49Ti solid-state nuclear magnetic resonance study.

The first 47,49Ti, 13C, 14N and 15N solid-state nuclear magnetic resonance (NMR) spectra of titanium carbide, nitride and a series of cubic carbonitrides have been obtained under both static and magic-angle spinning (MAS) conditions. The 15N samples were isotopically enriched by gas-solid exchange at 1000 degrees C in a closed system. The Ti spectra of the carbide and nitride are sharp, reflecting the well defined cubic symmetry of these compounds, but become considerably broadened in the carbonitride series, with the spectra being approximately the sum of TiC and TiN together with some small electric field gradient (EFG) effects. The resonance positions and widths of all the NMR spectra change as carbon is progressively replaced by nitrogen. A relationship is observed between the 13C chemical shift and the nitrogen content of the carbonitrides, suggesting a possible NMR method for estimating the composition of these compounds. Although electron paramagnetic resonance (EPR) spectra of all these compounds show typically metallic behaviour, the NMR spectra show few effects attributable to conduction electrons, probably due to the lack of s-orbital contributions to the conduction band.

Technological advances in poultry vaccines.

The work described in this paper represents an extended program utilizing both traditional and novel technologies to develop a range of poultry vaccines which target current or emerging opportunities in domestic and international marketplaces. The successes with the traditional products to date have been gratifying and the advent of a series of recombinant vaccines over the next few years holds promise for the generation of a range of novel immunobiologicals.

Scleritis and perceptive deafness: case report.

There is some evidence in the past decade that a similar syndrome to Cogan's syndrome may exist in which a scleritis substitutes for the nonsyphilitic interstitial keratitis. A case is reported of a female patient, aged 39, with nonrheumatoid scleritis and associated bilateral perceptive deafness.