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The focus of this paper is on the development of methodology for short-term (1–3 days) oceanic bioluminescence (BL) predictions and the optimization of spatial and temporal bioluminescence sampling strategies. The approach is based on predictions of bioluminescence with an advection–diffusion–reaction (tracer) model with velocities and diffusivities from a circulation model. In previous research, it was shown that short-term changes in some of the salient features in coastal bioluminescence can be explained and predicted by using this approach. At the same time, it was demonstrated that optimization of bioluminescence sampling prior to the forecast is critical for successful short-term BL predictions with the tracer model. In the present paper, the adjoint to the tracer model is used to study the sensitivity of the modeled bioluminescence distributions to the sampling strategies for BL. The locations and times of bioluminescence sampling prior to the forecast are determined by using the adjoint-based sensitivity maps. The approach is tested with bioluminescence observations collected during August 2000 and 2003 in the Monterey Bay, California, area. During August 2000, BL surveys were collected during a strong wind relaxation event, while in August 2003, BL surveys were conducted during an extended (longer than a week) upwelling-favorable event. The numerical bioluminescence predictability experiments demonstrated a close agreement between observed and model-predicted short-term spatial and temporal changes of the coastal bioluminescence. [ABSTRACT FROM AUTHOR]

Previous reports have indicated the association of periodontal diseases with elevated levels of serum immunoglobulin G (IgG) antibodies to periodontally relevant bacteria. Recent results from this laboratory suggest that enzymes proteolytic for immunoglobulins are important virulence factors of several periodontal bacteria. Specifically, enzymes from Porphyromonas (Bacteroides) gingivalis culture supernatant fluid (SF) cleaved human IgG (4 subclasses), IgA1 and IgA2, IgM, IgD and IgE. Proteolytic enzymes from Actinobacillus actinomycetemcomitans culture SF cleaved IgG, IgA and IgM. An enriched Ig proteolytic preparation form Capnocytophaga ochracea culture SF was shown to extensively cleave all 4 subclasses of human IgG. Extensive degradation of IgG and IgA in crevicular fluid samples on SDS-PAGE from periodontal disease sites of localized juvenile periodontitis (LJP) patients in comparison to little degradation in healthy sites indicated the potential role the proteolytic enzymes from periodontopathogenic bacteria may play in situ. Treatment of IgG with P. gingivalis, A. actinomycetemcomitans and C. ochracea SF resulted in similar patterns of degradation. LJP patients had significantly higher levels of IgG and IgA proteolytic activity in whole saliva than age-, sex-, and race-matched periodontal disease-free controls. however, not all of the proteolytic activity could be ascribed to bacterial proteases since neutrophils are also present in large numbers at diseased sites. Using similar techniques, lysates of neutrophils from healthy controls cleaved IgG, IgA and IgM. The observation of enhanced Ig cleavage activity in crevicular fluid and saliva in LJP patients suggest a role for Ig proteolytic enzymes in LJP. [ABSTRACT FROM AUTHOR]

To assess the effects of smokeless tobacco on the secretory immune system and dental caries, we examined users of smokeless tobacco and non-tobacco users. There were no significant differences in the prevalence of DMFS between users and non-users. There was significantly more salivary IgA, IgA2 and J-chain in users. Levels of salivary lysozyme and lactoferrin were significantly lower in users than controls. Because there was no difference in levels of secretory component in relation to the increased IgA levels of smokeless tobacco users, this suggests an effect of smokeless tobacco on secretory epithelial cells responsible for synthesis of secretory component, lysozyme and lactoferrin, and for the packaging of secretory component on IgA. There were only slight differences in salivary or serum antibody levels to Streptococcus mutans. These findings indicate that although smokeless tobacco has a significant influence on the synthesis of secretory IgA, the numbers of DMFS were similar between smokeless tobacco users and controls.

The levels of parotid salivary IgA and serum IgG antibodies from dental caries-resistant (CR) and caries-susceptible (CS) individuals to Streptococcus mutans antigens were determined. In general, the levels of salivary IgA and serum IgG antibodies to S. mutans antigens were significantly higher in CR subjects than in CS individuals. There were significantly higher levels of IgA2, but not IgA1, salivary antibodies to S. mutans whole cells in CR subjects than in CS individuals. These results led us to investigate the functional effects parotid saliva and sera containing these antibodies had on several factors associated with S. mutans virulence. Parotid saliva and sera from CR subjects significantly inhibited S. mutans growth, adherence, acid production, glucosyltransferase and glucose-phosphotransferase activities to a greater extent than saliva and sera from CS individuals. The data suggest that neutralization of S. mutans enzymes and inhibition of S. mutans virulence factors by saliva and serum may be responsible for the lower numbers of carious lesions in CR subjects.

Previously, we reported that smokeless tobacco users have significantly higher levels of immunoglobulin A and J chain in whole saliva than non-tobacco users. Because there was no difference in levels of secretory component between the two groups, the proportion of secretory component/immunoglobulin A was significantly lower in users than non-users. There was no significant difference in antibody function. In the present study, we examined immunoglobulin A from whole saliva of users and non-users to determine the effect of smokeless tobacco on the ability of secretory component to bind to immunoglobulin A containing J chain. Whole saliva was passed over an affinity chromatography filter unit coupled with anti-alpha heavy chain-specific antibody followed by passage over a molecular sieve high-performance liquid chromatography column. Peaks were collected and examined for immunoglobulin A, J chain and secretory component by enzyme-linked immunosorbent assay. Saliva from users had three significantly larger peaks (3-4 fold) at 280 nm than non-users, confirming the presence of a higher concentration of immunoglobulin A in users. The secretory component/J chain and secretory component/immunoglobulin A ratios for the largest peak were significantly less in users. This indicates that smokeless tobacco has an effect on the ability of secretory component to bind to immunoglobulin A without a loss in antibody function. This may occur either prior to immunoglobulin A/J chain binding to secretory component receptors on secretory epithelial cells or internal to the epithelial cells. These studies provide further evidence for the role of secretory component in mucosal immunity.

Previously, we reported that dental caries-resistant subjects, who have significantly fewer Streptococcus mutans in whole saliva than caries-susceptible patients, have significantly higher levels of naturally occurring binding and neutralizing parotid salivary immunoglobulin A and serum immunoglobulin G antibodies to native S. mutans antigens than caries-susceptible patients. Recent animal studies indicated that the immunogenicity of swallowed S. mutans may be altered by either saliva-coating or stomach acid-denaturation. These results suggest a difference not only in the quantity of antibody to S. mutans, but also in the antigenic epitopes that caries-resistant subjects synthesize antibody to as compared with caries-susceptible patients. In the present report, sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting studies indicate that caries-resistant subjects produce salivary immunoglobulin A and serum immunoglobulin G antibodies to several different (molecular weight: 94, 80, 40, and 35 kilodaltons) as well as several similar (molecular weight: 67, 55, and 30 kilodaltons) S. mutans epitopes as compared to caries-susceptible patients. This provides additional confirmation for our previous binding and functional antibody studies, indicating that caries-resistant subjects synthesize antibodies of different specificities than caries-susceptible patients. This study supports the concept of immune regulation of dental caries by naturally occurring antibodies induced by swallowing S. mutans antigens in saliva.

The authors have investigated the course of herpes simplex type 1 (HSV) keratitis in three different inbred strains of mice infected with four different HSV isolates. Severity of ocular disease and mortality is dependent upon both the virus isolate and the host strain. In particular, the likelihood of progression from self-limited dendritic keratitis to severe necrotizing stromal keratitis varies markedly among the virus-host strain combinations tested. When mice from strains resistant to stromal disease are crossed with mice from strains susceptible to stromal disease, the F1 offspring are resistant, suggesting that the gene(s) controlling resistance is dominant. Corneal stromal keratocytes and embryo fibroblasts from inbred mice differ significantly in their ability to support the replication of HSV in vitro. HSV replicates more efficiently in vitro in keratocytes from mice susceptible to stromal keratitis than it does in keratocytes from mice resistant to stromal keratitis. These findings provide evidence in an animal model for both virus- and host-related mechanisms that determine susceptibility to stromal keratitis.

Previous methods for estimating immunoglobulin protease activity have involved the use of enzyme-linked immunosorbent assays (ELISA) or sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography or Western blotting techniques. An alternative method has been developed to estimate proteolytic activity on human IgA1 and IgG using quantitative rocket immunoelectrophoresis. The method uses agarose containing anti-human IgA or anti-human IgG heavy chain-specific reagent to which protease-digested human immunoglobulin samples are applied to wells and electrophoresed overnight. Because proteolytic activity of immunoglobulins results in many smaller fragments, the optimal antigen-antibody ratio for precipitation changes and migration in an electric field results in a larger rocket. Consequently, the area of the rocket will be larger in a protease-treated immunoglobulin sample than a saline-treated immunoglobulin control. These increased rocket areas are correlated with our ELISA protease results (r greater than or equal to 0.90), as well as with our immunoblot results. The method is sensitive to increasing exposure to proteolysis, as well as to increasing amounts of protease. This technique can be used to quickly estimate the ability of a sample to cleave immunoglobulins.