The inflammatory mediators prostaglandin E2 (PGE2) and interleukin-1 beta (IL-1 beta) play critical roles in the inflammatory process leading to alveolar bone and connective tissue loss in periodontal disease. Data from a previously published 6-month clinical study demonstrated that twice daily use of 0.1% ketorolac tromethamine oral rinse prevented alveolar bone loss in adults with periodontitis. We further analyzed data from this study to examine the relationship between PGE2. IL-1 beta and bone loss. Patient mean PGE2 and IL-1 beta levels in gingival crevicular fluid (M-GCF) measured throughout the course of the study were directly compared to the maximum amount of alveolar bone height loss observed at a single study site in each patient. The maximum amount of bone loss measured was chosen for the analysis since the pattern of bone loss was clearly episodic in nature. A statistically significant correlation (r = 0.73, p = 0.001) exists between M-GCF PGE2 concentration and the maximum amount of bone height lost at individual patient study sites. The correlation between M-GCF IL-1 beta concentration and maximum bone height lost is also statistically significant (r = 0.66, p = 0.005). Over the 6-month duration of the study, both PGE2 and IL-1 beta were coordinately expressed in the placebo treatment group as reflected in the significant correlation between M-GCF concentrations of the 2 mediators (r = 0.81, p < 0.001). Treatment of patients with 0.1% ketorolac tromethamine twice daily for 6 months resulted in reductions of PGE2 in GCF and a negligible correlation between M-GCF PGE2 and M-GCF IL-1 beta (r = 0.42, p = 0.088). This lack of a strong association between the 2 mediators in the ketorolac treatment group provides a direct biochemical readout of the anti-inflammatory efficacy of ketorolac tromethamine oral rinse in patients with periodontitis. Further studies are warranted to determine the full diagnostic potential of M-GCF levels of PGE2 and IL-1 beta for predicting risk of alveolar bone loss in patients with periodontitis and monitoring periodontal therapy effectiveness.
Two clinical studies were conducted to determine the relative amounts of ketorolac detectable locally in the gingival crevicular fluid (GCF) and systemically in plasma after oral, topical drug administration. The rinse study compared topical administration of three concentrations of ketorolac tromethamine (0.1%, 0.05%, and 0.01%) in oral rinse formulations administered topically and a perorally administered capsule (10mg), and the dentifrice study compared two concentrations of ketorolac in dentifrice formulations (0.15% and 1.0%) with a 0.1% oral rinse, all treatments administered topically. The dose-corrected systemic availability of the three oral rinses evaluated in the rinse study relative to the peroral capsule was about 15%. However, the ratios of the observed maximum GCF ketorolac concentration to maximum plasma ketorolac concentration ranged from 22 to 49, compared to less than 1 for the peroral ketorolac capsule. Using this ratio as an estimate of the ability of a treatment to target the drug to the gingival tissue, these data indicate that the ketorolac oral rinses achieved greater delivery of drug to the gingival tissue (presumed site of action for periodontitis) with a lower systemic drug load than peroral administration of a ketorolac capsule. The dose-corrected relative systemic bioavailabilities for the dentifrice treatments with respect to the 0.1% rinse in the dentifrice study were 59.2% and 86.4% for the 1.0% and 0.15% dentifrices, respectively, indicating that significantly less ketorolac was systemically available from the two dentifrices relative to the oral rinse. The relative bioavailabilities of ketorolac in the GCF after dosing with the dentifrice formulations with respect to the rinse were 89.1% for the 1.0% dentifrice and 19.7% for the 0.15% dentifrice. Thus, the 1.0% dentifrice appears to provide statistically equivalent levels of ketorolac to the gingival tissue as the 0.1% oral rinse with significantly less systemic exposure. The T1/2 of ketorolac in the GCF was about 0.5h for all three treatments, which is significantly less than the plasma half-life of about 5.3h. These data suggest that GCF levels of ketorolac should remain above the IC50 for PGE2-stimulated IL-1 bone resorption for about 7h following treatment, assuming continuation of the first-order elimination observed over the first two postdosing hours. We conclude that oral rinses and dentifrices are effective and preferred vehicles for administration of ketorolac for use in treatment of periodontitis.
Digital subtraction radiography (DSR) has been shown to be a sensitive and specific method for the detection of small bony changes in periodontitis. The purpose of this study was to perform a multicenter validation of the DSR in human subjects. Seventeen subjects were enrolled at 3 centers. Feather-edged hydroxyapatite chips (approximately 1, 7 and 10 mg) were used to simulate osseous lesions. Bilateral radiographs were taken with and without chips. Geometry was standardized using a cephalostat and the order of radiographs was determined using a randomization plan. Radiographs were subtracted, lesions isolated, and quantified at a single center without knowledge of the randomization code or location of the chips used in each subject. The overall sensitivity and specificity in detecting 1 mg changes was 87.8% and 100%, respectively. Sensitivity and specificity in detecting 7 mg and 10 mg chips was 100%. A strong linear relationship between actual lesion mass and calculated mass was observed (R2 = 0.94, slope = 0.98, p < 0.0001). No significant differences were observed by center. These data indicate that the DSR is a valid technique for the assessment of alveolar bone changes in multicenter trials.
Systemic non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to reduce alveolar bone loss in periodontitis. This study assesses the efficacy of a topical NSAID rinse, containing ketorolac tromethamine as the active agent. Adult periodontitis patients (n = 55) were studied in this 6-month randomized, double blind, parallel, placebo and positive-controlled study. Each patient had a least 3 sites at high risk for bone loss as assessed by low dose bone scan. Groups, balanced for gender, were assigned to one of three regimens: bid ketorolac rinse (0.1%) with placebo capsule; 50 mg bid flurbiprofen capsule (positive control) with placebo rinse; or bid placebo rinse and capsule. Prophylaxes were provided every 3 months. Monthly examinations assessed safety, gingival condition, and gingival crevicular fluid PGE2. Standardized radiographs were taken at baseline and at 3 and 6 months for digital subtraction radiography. A significant loss in bone height was observed during the study period in the placebo group (-0.63 +/- 0.11; P < 0.001), but not in the flurbiprofen (-0.10 +/- 0.12; P = 0.40) or ketorolac rinse (+0.20 +/- 0.11 mm; P = 0.07) groups. Nested ANOVA revealed that ketorolac and flurbiprofen groups had less bone loss (P < 0.01) and reduced gingival crevicular fluid PGE2 levels (P < 0.03) compared to placebo. ANOVA suggests (P = 0.06) that ketorolac rinse preserved more alveolar bone than systemic flurbiprofen at the dose regimens utilized. These data indicate that ketorolac rinse may be beneficial in the treatment of adult periodontitis.
At the US Army Ballistic Research Laboratory (BRL), Aberdeen Proving Ground, Md., weapon system analysts use background models in order to: 1) establish ‘clutter’ thresholds for firing algorithms: and, 2) to study the masking and false alarm effect of background in their effort to evaluate the performance of various weapon systems. The BRL has received from US Army Engineer Waterways Experiment Station (WES) several large data bases comprised of blackbody temperatures derived from measurements obtained with an IR sensor. The sensor was mounted on a helicopter and scanned in the cross-track direction perpendicular to the direction of flight (in-track). The data consist of temperatures of scene elements (pixels) for a plowed field, a forested area, and a grassy field. The primary objective of this research is to provide a simple mathematical model which provides simulated data that are consistent with descriptive statistics from the original spatially correlated data base. Such statistics include the mean and standard deviation of temperature, and its ‘energy spectrum’. The Mathematical Sciences Institute (MSI) at Cornell University have suggested time series models and a Spatial Moving Average (SMA) model as two approaches to the problem. One long term objective of this type of investigation is to construct a method for relating parameters in the model to physical constants. If successful, the model may then be extended over the diurnal cycle and seasons.
An experiment was performed to determine whether humoral- or cell-mediated immune responses of cattle to a Brucella abortus vaccine were influenced by the stage of gestation. Heifers were vaccinated 2 mth before and 2 mth after breeding with cell envelopes of B. abortus in an oil adjuvant containing trehalose dimycolate and muramyl dipeptide. Control groups received adjuvant alone or no vaccine. Following breeding, vaccinated animals were divided into pregnant and nonpregnant subgroups. Immune responses to two outer membrane proteins were measured at monthly intervals by ELISA and lymphocyte blastogenesis tests. Skin tests were performed during the ninth month of gestation. Vaccination induced sustained immune responses, but few differences were detected between pregnant and non-pregnant animals. The relative increase in IgA antibodies to group 3 protein in nonpregnant heifers exceeded that in pregnant heifers during months 4 and 6 of gestation (P < 0.05). Dermal hypersensitivity, measured by changes in double skin thickness, was significantly greater in nonpregnant heifers to porin (P < 0.01) and group 3 (P < 0.05) antigens at 24 h post-injection, but no significant differences in skin thicknesses or in the nature of the lesions were observed at 48 h. Animals which received adjuvant alone demonstrated negligible responses. Pregnancy had no significant effect on the responses of lymphocytes to phytohemagglutinin (PHA) or Concanavalin A (Con A). However, plasmas from nonvaccinated pregnant heifers taken during the sixth and seventh (but not eighth or ninth) months of pregnancy decreased responses of normal donor cells to PHA and Con A when compared with those in autologous plasma (P < 0.05).
The present study was designed to evaluate our previous estimates for riboflavin requirement, 0.96 mg/1000 kcal during nonexercise and 1.16 mg/1000 kcal during exercise in overweight women. Two groups of 6 weight reducing women consumed either 1.16 mg riboflavin/1000 kcal (HR) or 0.96 mg/1000 kcal (MR). The study was two, 3 period by 2 treatment (exercise or nonexercise) crossover designs, one design at each level of riboflavin. Erythrocyte glutathione reductase activity coefficients (AC) significantly increased in both groups from 1.16 +/- .02 to 1.20 +/- .03 in group HR and from 1.31 +/- .04 to 1.36 +/- .02 in the MR group during nonexercise and exercise, respectively. ACs increased in the HR group due to an increase in total enzyme activity while ACs increased in the MR group due to a decrease in basal enzyme activity reflecting decreased flavin availability. There were no differences in aerobic capacity, weight loss, nor change in lean body mass between the two groups. Thus, 0.96 mg/1000 kcal was not adequate during either nonexercise or exercise periods while the 1.16 mg/1000 kcal was adequate.
The immune response of cattle to nonliving vaccines derived from Brucella abortus rough strain 45/20 was studied. Vaccines contained trehalose dimycolate and a derivative of muramyl dipeptide. N-acetylmuramyl-L-alpha-aminobutyryl-D-isoglutamine. A factorial experiment was designed to test the effects of type of antigen, quantity of antigen, and quantity of mineral oil on the immune response to porin. Muramyl dipeptide was kept constant at 5 mg per dose, and 1 part of trehalose dimycolate was incorporated for two parts of dry matter. Over a 10-week period, blastogenesis responses to porin were largest in cattle immunized with outer membranes; the highest antibody titers to the porin-lipopolysaccharide complex were achieved by immunization with detergent-extracted outer membrane proteins. There was no advantage in the use of 25, rather than 5, mg of any of the antigens, but antibody responses were improved by increasing the quantity of oil from 0.6 to 1.8 ml per dose. In other animals, blastogenesis and antibody responses were sustained at high levels longer than 3 months after two vaccinations with outer membrane proteins. Intradermal injection of porin evoked inflammatory reactions histologically consistent with delayed-type hypersensitivity. Cross-reactions in cases of delayed-type hypersensitivity occurred with porin derived from a smooth strain of B. abortus but were less extensive than in the blastogenesis test. The magnitude of the delayed-type hypersensitivity and blastogenesis responses induced by vaccination exceeded those observed after natural or experimental infections. No ill effects were observed after vaccination. These findings provide a basis for the use of trehalose dimycolate and muramyl dipeptide adjuvants in evaluating nonviable vaccines for bovine brucellosis.