摘要:

Using an agar‐skim milk gel method, over 300 oral bacterial isolates were tested for their ability to produce trypsin or chymotrypsin inhibitor. Eleven bacterial strains, including seven isolates identified asBacteroides intermedius, were found to inhibit both proteolytic activities. The inhibitory factors of the 11 bacterial strains could be divided into two categories: i) heat‐stable and dialysable, and ii) heat‐labile and non‐dialysable. The protease inhibitor activity ofB. intermediusstrains, which belongs to the latter category, was found in a membrane fraction as well as in a membrane‐free extract. Furthermore, three strains ofB. intermediusshowed this inhibitory activity in the culture supernatant. In combination with plasma‐derived protease inhibitors, the production of these additional protease inhibitors by oral bacteria could protect the host from tissue

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01726.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Immunolocalization techniques were used to examine the expression of the cell surface receptors of EGF in normal and inflamed gingival tissue. Detectable levels of receptor were not observed in any (0/6) of the normal tissue biopsies examined; in contrast, the EGF‐receptor was expressed by both epithelial and stromal cells in 7/9 of the inflamed tissue biopsies. Receptor expression by epithelial cells in inflamed tissues exhibited a variable distribution pattern. In the majority of sections, staining was confined to cells in the spinous, granular and cornified cell layers, with little in the basal layer. Occasionally, isolated islands of stained epithelial cells were present, suggesting their clonal origin. Staining for the EGF receptor was also observed in fibroblasts and endothelial cells throughout the lamina propria of inflamed tissue. Positive staining for the receptor ligand (EGF) was observed in both normal and inflamed tissue. These data suggest that an up‐regulation of cell surface receptors for EGF occurs during the inflammatory response, this resulting in an increased cellular responsiveness to

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01727.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Our purpose was to determine the urea concentration in minor mucous gland (MMG) secretions and the pH at proximal and distal aspects of the lower surface of artificial plaquein vitroduring infusion of urea solutions over the surface, at different film velocities. Saliva is present in the mouth as a slowly moving film (ca. 0.1 mm thick) with an estimated velocity in the range of 0.8–8.0 mm/min. At low velocities, due to the accumulation of bacterial products, a progressive increase in their concentration may occur in both the plaque and the overlying salivary film at the distal edge (where the film leaves the plaque).S. vestibularis, an oral micro‐organism possessing ureolytic activity, was combined with 1% agarose, to give a urease Vmax similar to that of natural plaque. The artificial plaque was in the chamber (6.0 × 6.0 square and 0.5 or 1.5 mm deep) of a diffusion apparatus, and a urea‐containing artificial saliva (3.3 or 13.2 mmol/ 1) was infused over the surface, as a film 0.1 mm deep, at velocities of 0.8, 8.2 and 86.2 mm/min. At the lower (physiologically normal) urea concentration and the two lower film velocities, most urea appeared to be metabolized at the proximal end of the plaque, which developed a higher pH. At the higher urea concentration, and a film velocity of 8 mm/min, a higher pH was found at the distal end. This was probably due to the combination of greater urea availability and a reduced rate of ammonia loss distally. At a film velocity of 86.2 mm/min, proximal/distal pH gradients did not develop. Thus the salivary film velocity may influence the pH and ammonia level in plaque and perhaps the development of gingivitis. In unstimulated and stimulated MMG secretions, which are the secretions in contact with the buccal surfaces of most teeth, the urea concentrations were 5.27 ± 1.07 and 4.38 ± 1.51 mmol/1, resp

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01728.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Three serological markers of immune cell activation, interleukin‐2 (IL‐2), soluble interleukin‐2 receptor (sIL‐2R), and interleukin‐4 (IL‐4), were measured by enzyme‐linked immunosorbent assays in 20 control subjects and 26 periodontitis patients. The experimental group comprised 19 juvenile/post‐juvenile and 7 severe generalized periodontitis patients with radiographic evidence of alveolar bone loss. Although some control sera contained immunoreactive IL‐2 (2 of 20) and IL‐4 (3 of 20), all contained sIL‐2R, the levels of which correlated well with age (r = 0.644). Mean levels of all three markers were significantly elevated in the sera of patients with periodontal disease compared to control values. However, there was a wide variation in the amounts detected; IL‐2 (0.21‐173.33 ng/ml); sIL‐2R (217.95‐1177.27 units/ml); IL‐4 (3.17‐16.35 pg/ ml), which did not correlate with either the degree of bone loss or pocket formation observed clinically. Moreover, there was no correlation between the levels of IL‐2, slL‐2R or IL‐4 for any given individual in the experimental group. The finding that only 2 of the control sera contained IL‐2 (10%) compared to 23 of the periodontitis patients (88.5%) suggests that, of the three parameters investigated, the measurement of IL‐2 could provide a sensitive laboratory test for assessing periodontal disease activity. Nevertheless, a definitive study to determine the relationship of serum IL‐2 levels to clinical parameters of disease activity will be necessary to confirm this observation. These results provide direct evidence for the systemic activation of immune cells in periodontitis, and suggest a role for IL

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01729.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The predominant cultivable bacteria associated with juvenile periodontitis (JP) in China were studied for the first time. Subgingival plaque samples were taken on paper points from 23 diseased sites in 15 JP patients and from 7 healthy sites in 7 control subjects. Serially diluted plaque samples were plated on nonselective blood agar and on MGB agar, a selective medium for the isolation ofActinobacillus actinomycetemcomitans. Fifteen or more isolated colonies from each sample (in sequence without selection) were purified for identification. The results indicated that the microfiora in healthy sulci of the 7 control subjects was significantly different from that in diseased sites of JP patients. The predominant species in healthy sulci wereStreptococcusspp. andCapnocytophaga gingivalis. In JP patients,Eubacteriumsp. was found in significantly higher frequency and proportion.Actinobacillus actinomycetemcomitanswas not detected in any samples. It appears that this species is not associated with juvenile periodontitis in China.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01730.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The effect of the non‐steroidal anti‐inflammatory drug, naproxen, in reducing periodontal disease activity was assessed in 15 patients with rapidly progressive periodontitis. All patients in this double‐blind study were treated with scaling and root planing. Thereafter, 7 patients receiving 500 mg naproxen b.i.d. for 3 months, and 8 patients received placebo. Disease activity was assessed in three ways. First, alveolar bone height was determined using standardized radiography. Second, alterations in alveolar bone metabolism were assessed using 99m‐Tc‐methylene diphosphonate uptake prior to dosing and 3 months later. Finally, bone loss or gain was detected using digital subtraction radiography. In this study, conventional subtraction images were processed to isolate the area of change and superimpose the change on the original radiograph. This allowed determination of both the direction and location of osseous changes. There was significantly less bone loss as determined by analysis of bone height during the 3‐month study in the naproxen‐treated patients when compared to the placebo‐treated patients (p<0.001). Radiopharmaceutical uptake was significantly reduced in the alveolar bone in patients receiving naproxen (p<0.03), whereas no significant change was observed in the placebo‐treated patients. Furthermore, the subtraction radiographs showed a significant increase in the proportion of teeth demonstrating bone gain in the naproxen‐treated group. These findings indicate that naproxen may be a useful adjunct to scaling and root planing in patients with rapidly progre

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01731.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The potential inhibitory effect of chlorhexidine digluconate on the intergeneric coaggregation of 11 pairs of Gram‐positive organisms was compared to its ability to inhibit coaggregations of 14 pairs comprised of both a Gram‐positive and a Gram‐negative cell type. Dramatic differences in the inhibitory effectiveness of the antimicrobial compound on the two kinds of coaggregating pairs were found. Gram‐positive pairs were not inhibited at a concentration of 0.25%, whereas the coaggregations involving a Gram‐negative partner were usually completely blocked at concentrations as low as 0.01%. Similar effects to chlorhexidine digluconate were found with octenidine dihydrochloride and cetylpyridinium chloride, while sodium dodecylsulfate was inhibitory only at 10‐ to 50‐fold higher concentrations. These results suggest that chlorhexidine digluconate, octenidine dihydrochloride, and cetylpyridinium chloride may be effective inhibitors of later microbial colonizers of dental plaque but may not disturb a normal healthy ind

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01732.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

We investigated the penetration and clearance of antigen in the rat gingiva and the antigen‐specific antibody response in the draining lymph nodes. Rats were primarily immunized into the alveolar submucosa with horseradish peroxidase (HRP) in complete Freund's adjuvant. Ultrastructural demonstration of antigen and specific antibody was performed by incubation of cryosections in an HRP solution, followed by peroxidase cytochemistry. Anti‐HRP antibody‐containing cells were observed in the draining lymph nodes from 2 to 9 weeks after immunization. The bulk of these cells were located in the medullary cords. The extracellular antibody and antibody‐containing cells were also found in germinal centers (GCs) from 3 to 9 wk, and 3 wk, respectively, after immunization. The results suggest that the specific antibody response was most enhanced 3 wk after primary immunization. Therefore, at this time we further challenged rats with the topical application of HRP to the gingival sulcus. The results showed that antigen penetrated through the junctional epithelium into the underlying connective tissue and from here was cleared by macrophages or via the lymphatics. In the draining lymph nodes, antigen first appeared in the subcapsular sinus and eventually became retained within GCs. Between 3 and 5 days, the GCs of challenged rats contained more mature‐type anti‐HRP antibody‐containing cells than those of non‐challenged rats. The sequence of events observed suggests that antigen challenge applied topically to the gingival sulcus can induce the active GC reaction in the draining lymph nodes of

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01733.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

In a multicenter study of the effects of tetracycline (TC) fiber therapy, subgingival plaque samples were tested for 6 probable periodontal pathogens by DNA probe analysis. Levels ofActinobacillus actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatum, Porphyromonas (Bacteroides) gingivalis, Prevotella intermedia (Bacteroides intermedius), andWolinella rectawere quantitatively determined in samples taken at baseline, and immediately after TC fiber removal, control fiber removal, and scaling and root planing. At untreated sites, samples were taken at baseline and 10 d later. Specificity of the DNA probe method was evaluated by testing the hybridization to 83 reference cultures. Interaction of theF. nucleatumprobe withFusobacterium periodonticum, and of theW. rectaprobe withWolinella curvawere the only cross‐hybridizations noted. Species were detected at an average sensitivity of 2.9 × 104organisms per sample. Approximately 70% of sites were initially infected withP. gingivalisandF. nucleatum; 50% withP. intermediaandE. corrodens;infections withW. rectaandA. actinomycetemcomitanswere less common (36% and 11% respectively). The average numbers of organisms found in plaque samples were highest forF. nucleatum, P. gingivalis, andP. intermedia(ca. 106).E. corrodens, W. recta, andA. actinomycetemcomitansoccurred at 10‐fold lower levels. Bacterial numbers and proportions of species in subgingival sites from the five centers did not differ appreciably. Both TC fiber therapy and scaling decreased the number of sites infected with all the monitored species. The bacterial composition at untreated sites and at sites where control fibers were placed was not significantly altered. The percentage reduction of the number of sites with delectable infection varied with each species: from 86% withW. rectato approximately 40% withP. gingivalis. Significant reduction of pocket depth and bleeding occurred at TC fiber‐treated sites infected with each of the species. Significant attachment level gain occurred only at sites initially infected withP. gingivalisand treated with TC

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01734.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Oligonucleotide DNA probe and selective cultural methods were compared in their ability to monitor 6 putative periodontal pathogens in a study evaluating local tetracycline fiber therapy. Subgingival plaque was sampled from 4 sites in each of 20 subjects. Samples were taken before and after therapy from sites assigned to the following test groups: tetracycline (TC) fiber, scaling and root planing, control fiber, and untreated. Each sample was analyzed by both DNA probe and cultural methods. Total anaerobic cultivable counts,Porphyromonas (Bacteroides) gingivalisandPrevotella intermedia (Bacteroides intermedius)were enumerated on nonselective blood agar.Actinobacillus actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatumandWolinella rectawere isolated on selective media. TC fiber therapy and scaling reduced total cultivable counts from an initial value of 1 × 107to approximately 2 × 105following therapy. Total counts at untreated sites and at sites with control fibers did not change from baseline.A. actinomycetemcomitansandE. corrodenswere detected more frequently by the cultural method; the other monitored species were detected more frequently by DNA probes than by the cultural methods. Agreements between methods were: 77.2% forA. actinomycetemcomitans; 72.2% forP. intermedia; 75.6% forE. corrodens; 39.4% forF. nucleatum; 35.6% forP. gingivalis; and 68.9% forW. recta. Limitations of the selective cultural methods used probably contributed to the discrepancies forP. gingivalisandF. nucleatum. DNA probe and cultural methods indicated comparable levels of suppression of the monitored species following TC fiber therapy and scaling. The microbiota of control fiber and untreated sites did not appear to be significantly altered by either metho

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1991.tb01735.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY