CD8+ T cells from feline immunodeficiency virus (FIV) infected cats suppress exogenous FIV replication of their peripheral blood mononuclear cells in vitro.

Feline immunodeficiency virus (FIV) isolates from domestic cats have been classified into five subtypes, designated A, B, C, D and E. Although many FIV-infected cats may have frequent contact with multiple strains of FIV, they usually become infected with a single FIV subtype. In the present study, we demonstrate that peripheral blood mononuclear cells (PBMC) of FIV infected cats were resistant to exogenous FIV (second virus) replication in vitro and that the resistance of these PBMC was mediated by CD8+ T cells. In cats with a low anti-FIV activity of CD8+ T cells, the proviral DNA of the second virus inoculated into PBMC was detected intracellularly, and both the second and the originally infecting strain (original virus) were produced in the culture supernatant. In contrast, in cats with a high anti-FIV activity of CD8+ T cells, both the proviral DNA of the second virus and the original virus were detected in PBMC intracellularly, but neither virus was produced in the culture supernatant. However, when PBMCs from these cats were depleted of CD8+ T cells, the RNA of both viruses was detected in the culture supernatant. These results suggest that CD8+ T cells inhibit the late phase of FIV replication after viral integration. Moreover, the inhibition was also effective against FIV strains of different subtypes from that of the original strain. It appears that the CD8+ T cell-mediated immune response plays important roles in the maintenance of an asymptomatic state in FIV-infected cats and their resistance to superinfection.

The influence of blood contamination on bond strengths between dentin and an adhesive resin cement.

The objective of this study was to determine in which step of adherent surface treatments blood contamination affects the bond strength between an adhesive resin and dentin. The coronal part of bovine incisors was polished flat to expose the dentin. The specimens were randomly divided into three groups and specific surface treatments were applied to each group: (1) a self-etching primer application (SP group); (2) 38% phosphoric acid etching followed by primer (non-HC group); (3) acid etching followed by 10% sodium hypochlorite solution application and primer (HC group). The dentin surface was contaminated by human blood before or after either step of the surface treatments. The contaminated surfaces were washed with water after 30-second exposure and air-dried. A stainless-steel rod was adhered on the dentin surface with Panavia 21 after completing the surface treatment(s), and the tensile bond strength was measured. Fifteen subgroups including control groups were tested. If blood contamination occurred before collagen fibers were exposed by either phosphoric acid etching or self-etching primer application, the contamination presented almost no influence on bond strength. Blood contamination of the dentin surface where collagen fibers had been exposed decreased the bond strength. However, when the contaminated collagen fibers were dissolved or when the contamination occurred after the exposed collagen fibers were dissolved, the bond strength was maintained. The bond strength was markedly decreased when the contamination occurred after the primer application (Scheffé's Comparison, SP group: p = 0.0003, non-HC group: p < 0.0001), but was restored by reapplication of the self-etching primer. This study revealed that the effects of blood contamination on the bond strength of adhesive resin to dentin vary greatly depending on the adherent surface conditions.

Effect of thromboxane synthetase inhibitor on feline infectious peritonitis in cats.

Two cats with abdominal effusion and anorexia were diagnosed as feline infectious peritonitis (FIP). We tried to evaluate the effect of thromboxane (Tx) synthetase inhibitor, ozagrel hydrochloride, on the progression of symptoms and clinicopathologic data characteristic to FIP. After administration of Tx synthetase inhibitor, improvement of appetite and activity, decreases of peritoneal effusion, reduction of leukocyte number to normal level, and improvement of hyper gamma-globulinemia were found in 2 cats with FIP. These findings suggest that the vasculitis in FIP can be successfully treated with Tx synthetase inhibitor which inhibits platelet aggregation.

Etched-porcelain resin-bonded onlay technique for posterior teeth.

Remarkable advances in adhesive dentistry have made it possible to strongly bond porcelain to enamel and dentin. This evolution has dramatically changed restorative dentistry and has produced a new, highly esthetic, and strong restoration--etched-porcelain resin-bonded restorations. These restorations can be placed with confidence on posterior teeth. They are virtually indistinguishable from natural tooth structure and, thus, provide additional treatment alternatives for patients who desire natural-appearing posterior teeth. Etched-porcelain resin-bonded onlays on posterior teeth not only are an excellent restorative modality for moderately broken-down teeth but also may be used to bring caries-free teeth into occlusion. The latter can be an option for stabilizing occlusion for some patients with posterior open bite due to various causes. This article presents clinical and laboratory techniques for etched-porcelain resin-bonded onlays on posterior teeth.

Long-term follow-up study on drop-out TMD patients with self-administered questionnaires.

Although patient attrition might be a serious threat to the validity of treatment-outcome studies on temporomandibular disorders (TMD), studies on TMD patient attrition are scarce. Of the 1405 consecutive TMD patients examined in a recent 10-year period, 367 (26.1%) drop-out patients or patients identified with a control group were sampled. A mailed questionnaire failed to reach 41 patients, and 203 (62.3%) were returned. The questionnaire elicited information on reasons for dropping out, changes in symptoms, treatment received in other clinics after dropping out, present treatment needs, and current signs and symptoms. Dropouts were divided into two groups: (1) those who failed to show up for their first scheduled appointment after the clinical examination; (2) those who failed to complete treatment. A group of patients who were judged by the examiner not to need treatment were included as a control group. The main reasons for dropping out were environmental obstacles, perceived improvement of the disease, and dissatisfaction with services. Only 21.7% considered themselves to be in need of treatment, and only 10.3% had visited other clinics after dropping out. Only 8.9% complained of the continued aggravation of symptoms, whereas 57.6% reported improvement. In addition, pain, dysfunction, and daily activity limitation tended to improve with time, although temporomandibular joint noise tended to persist. These results suggest that TMD signs and symptoms tend to decrease in patients after dropping out, and that the natural fluctuation of TMD signs and symptoms should be taken into consideration when treating TMD.