摘要:

The effects of inflammation on collagenase and gelatinase were studied in dog gingiva. Inflammation was induced by the placement of cervical ligatures. Collagenase activity was measured using soluble [14C]‐acetylated collagen with high specific activity as substrate and separating the reaction products by 50% dioxane (Terato et al. 1976). Two forms of collagenase, a soluble enzyme free from the substrate and an insoluble enzyme bound to the substrate, were extracted by neutral salt solution and by sequential sonication in low and high salt buffers, respectively. Treatment with a high concentration of trypsin was necessary for detection of collagenase activities in both extracts. The collagenase activities in the neutral salt extract and the first sonic extract were significantly higher in inflamed gingiva after 1 week of plaque formation than in healthy gingiva, but that in the second sonic extract showed no significant increase. After 3 weeks of plaque formation, the activities in neutral salt extract and the first sonic extract of inflamed gingiva similarly showed significant increases relative to controls. On the other hand, gelatinase activity did not vary significantly with the induction of inflammatio

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00329.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Cultured human gingival fibroblasts secrete a latent collagenase (EC 3.4.24.7). This latent collagenase can be activated proteolytically by trypsin and chemically by the organomercurials, p‐aminophenylmercuric acetate (APMA) or p‐chloromercuribenzoate (PCMB). Under optimal activation conditions, the latent collagenase was activated to the same extent by either trypsin or the organomercurial, APMA. The activated fibroblast collagenase hydrolyzed14C‐collagen fibrils and cleaved Type I collagen in solution into three‐quarter and one‐quarter length cleavage fragments, which appeared identical to those produced by human gingival tissue collagenase obtained from organ culture. The fibroblast collagenase was inhibited by EDTA, 1,10–phenanthroline, cysteine, dithioerythritol, heparin, human serum, and α2‐macroglobulin but not by phenylmethylsulfonyl fluoride or N‐ethylmaleimide. The pH optimum for this neutral metalloproteinase was between 7.5 and 9.0. In addition, the secretion of this latent collagenase by cultured fibroblasts can be stimulated by the endocytosis of either mycostatin or

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00330.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The connective tissues of diabetic humans and experimental animals exhibit abnormalities in collagen metabolism including an increased production of collagenolytic enzymes by gingival explants in tissue culture. In the current study, gingival tissue and skin were obtained from control and diabetic rats, the latter on the 5th, 10th, 15th, and 22nd day after inducing the disease with streptozotocin. Extracts of the tissues were assessed for collagenase activity using either14C‐labeled collagen fibrils or Peptide‐P as substrate and by detecting collagenase digestion products by SDS‐polyacrylamide gel electrophoresis. Elastase was measured using the specific substrate, succinyl‐(L‐Alanyl)3‐p‐nitroanilide. Diabetes increased the activity of collagenase in extracts of gingiva and skin; elastase, however, was increased dramatically only in the latter tissue. These findings (1) indicate that diabetes‐induced enhanced gingival collagenase activity occursin vivoas well asin vitroand (2) explain, at least in part, the greater loss of collagen in skin than in gingiva of the diabetic rat and other complications such as unusually severe period

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00331.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Hyaluronic acid synthesis was studied in human gingival fibroblast cultures exposed to human dental bacterial plaque extract. The cells were stimulated to produce large amounts of hyaluronic acid (HA) into the culture medium. The extract did not have any direct effect on the activity of hyaluronic acid synthetase enzyme complex, indicating that the increased hyaluronic acid synthesis was caused by metabolic alterations in gingival cells. Dental plaque extract also decreased the molecular weight of hyaluronic acid. This was obviously caused by the plaque derived hyaluronidase, because denaturation of plaque proteins by heating prevented this degradation. On the other hand, the stimulatory effect on the HA synthesis by the plaque extract was not destroyed by heating. The increased production of low molecular weight HA by gingival fibroblasts after plaque exposure is suggested to have a role in the pathogenesis of chronic periodontal diseasein vivo.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00332.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Lipopolysaccharide (LPS) has been purified fromBacteroides gingivalis. The purity of this LPS is evidenced on ultracentrifugation, immunoelectrophoresis, and chemical analyses. On comparison with LPS from aerobic enteric organisms, LPS fromBacteroides gingivalisexhibits minimal potency when tested for pyrogenicity in rabbits and mitogenicity in mouse spleen cells. On the other hand, purified LPS fromBacteroides gingivalisexhibits high potency in its ability to stimulate45Ca release from prelabeled fetal rat bones and to inhibit Ca influx into osteoclast‐like cell

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00333.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Dextran‐mediated agglutination has been both proposed and opposed as a mechanism for cohesive interactions betweenActinomyces viscosusand streptococci in dental plaques. In their Studies, opponents of this mechanism used laboratory strains subculturedin vitrofor unknown periods, whereas its proponents had previously shown that laboratory passage ofActinomycesstrains weakened this trait. To clarify this issue, eighty‐eight strains ofA. viscosusandActinomyces naeslundiifreshly isolated from the human oral cavity and hardly subculturedin vitro, were studied for enhancement of agglutination by commercially obtained polysaccharides including dextran, inulin, agarose, and starch and polysaccharides isolated from sucrose‐grownStreptococcus mutans, Streptococcus sanguis, andStreptococcus salivarius. Few of the strains exhibited higher agglutination scores in buffer containing any of the various polysaccharides than in control buffer free of the polysaccharides. Infrequent polysaccharide agglutinability of these human isolates, even by polysaccharides likely to be encountered in dental plaques, casts doubt on this explanation forActinomyces’cohesive interactions in plaque fo

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00334.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The effect of phenytoin therapy on periodontal indices, plaque microbiology, and gingival overgrowth was studied. Plaque, gingivitis, and calculus indices and pocket depth were recorded for anterior and posterior teeth of 89 subjects partitioned into 5 groups, a control group, and 4 groups of patients receiving phenytoin therapy with differing severity of gingival overgrowth. A survey of the major oral microorganisms present in marginal plaque was also done. The clinical indices increased with increasing severity of overgrowth. Patients with no or minimal overgrowth had clinical indices equal to or less than those of controls. The proportions of the major oral genera in marginal plaque samples from the groups were similar except for the patients with the most severe gingival overgrowth (mentally retarded and institutionalized). The microbe proportions from neither anterior nor posterior sites had a distinct relationship to severity of gingival overgrowth. Furthermore, no differences were found between clinical parameters or plaque microbiology at the anterior sites of patients who had greater anterior than posterior overgrowth. More frequent Correlations occurred among clinical parameters than among microbial percentages or between microbial percentages and clinical indices. This study does not support a specific marginal plaque etiology for phenytoin associated gingival overgrowth.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00335.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Recovery and identificationin vitroof lymphocytes from gingival tissue was carried out for 20 patients with chronic marginal gingivitis. A combination of 90 min incubation in a collagenase‐containing medium followed by mechanical disruption through a stainless‐steel grid resulted in a mean yield of 2.42 × 105(S. D. ± 1.26 × 105: n = 16) lymphocytes per 100 mg or tissue. When Ficoll density centrifugation was introduced into the recovery procedure, the mean lymphocyte yield dropped to 2. 15 × 104(S. D. ± 0.99 × 104: n = 4) per 100 mg. Mean viability of recovered lymphocytes was 78% (S. D. ± 5%: n =16) and for Ficoll separation, 77% (S. D. ± 1%: n = 4). In cell suspensions obtained from 12 or the patients, T lymphocytes were identified by rosette formation with sheep erythrocytes, and B cells were quantitated using fluorescent identification of membrane immunoglobulin. Macrophages were identified on the basis of non‐specific esterase characteristics. Tire predominant lymphocytes round were T cells, with a mean proportion of 53.9% (S. D. ± 5.6%); the mean proportion of B cells was 32.7% (S. D. ± 5.4%). Macrophages accounted for a mean of 7.7% (S. D. ± 2.8%) or the recovered lymphoid cells. The lymphocyte‐plasma cell ratio in recovered cell suspensions was 7:1 compared with a ratio of 1.7:1 noted in his

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00336.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

In the present study we have investigated the effect of factors released by cells derived from porcine epithelial rests of Malassez (ERM) on bone resorptionin vitro. The osteolytic effect of these cells was tested by co‐culturing them with fetal rat calvariae and then measuring the cumulative change in calcium concentration of the culture medium. When ERM cells were cultured with calvariae for 4 days, there was a significant increase in calcium release from the bones compared with bones cultured without ERM. ERM cells alone did not change the calcium concentration of the culture medium. When calvariae there cultured in medium that had been collected from ERM cultures, significant bone resorption could also be obtained. Indomethacin (200 ng/ml), an inhibitor of prostaglandin synthesis, inhibited calcium release from control calvariae and from calvariae cultured with ERM. However, calvariae cultured in the presence of ERM and indomethacin released significantly more calcium than those cultured in the presence of indomethacin alone. Thus, factors other than PG account for the osteolytic effect of ERM. Other cells cultured from oral tissues, such as gingival fibroblasts and fibroblasts from periodontal ligament as well as rat osteosarcoma cells also stimulated calcium release from calvariae. These results show that many cell types have the capacity to release bone resorbing factorsin vitroand support the belief that under suitable conditionsin vivobreakdown of alveolar bone may be stimulated by tissues proximal to i

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00337.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The ability of a high F intake to inhibit alveolar bone loss was assessed over a period of one year in strain STR/N mice. This strain is susceptible to periodontal disease in the absence of dietary or traumatic stimuli, with progressive alveolar bone loss beginning in adulthood. Despite a very high bone F level, alveolar bone loss was not significantly different from that occurring in mice of the same strain with a low F intake. The resistance of alveolar bone to destruction does not appear to be a major factor in the progression of periodontal disease.

ISSN:0022-3484    

DOI:10.1111/j.1600-0765.1983.tb00338.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY