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21.
Background:  The peripheral giant cell granuloma is a relatively common non-neoplastic inflammatory lesion of gingiva, but the etiopathogeny remains unknown. This study aimed to evaluate the importance of human cytomegalovirus and Epstein–Barr virus in a peripheral giant cell granuloma of a 47-year-old female.
Methods:  The lesion was studied clinically, histopathologically, immunologically and virologically using established procedures.
Results:  The gingival growth was located at the mesial surface of the maxillary left canine having a vital pulp. The mass was 12 × 21 mm in size and exhibited a smooth surface with no evidence of fluctuation on palpation. An excisional biopsy revealed giant cells in a fibrohistiocytic stroma with areas of haemorrhage. Serum protein levels and lymphocyte subsets were within normal limits, except CD3+ and CD4+ cells were below normal ranges. Polymorphonuclear leukocytes expressed p150,95 (CD11c/CD18) and CXCR-2 receptors within normal ranges, but the CXCR1 receptor showed decreased density, and CD15 were below normal range. A virological sample of the tooth surface adjacent to the gingival swelling yielded 7.6 × 103 copy-counts of cytomegalovirus and 4.3 × 103 copy-counts of Epstein–Barr virus.
Conclusions:  The clinical and histological findings were consistent with the diagnosis of peripheral giant cell granuloma. Cytomegalovirus has the potential to induce multinucleated giant cells, and the possibility that the virus contribute to the development of peripheral giant cell granuloma merits further study.  相似文献   
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Bacteroides heparinolyticus in subgingival plaque was identified using a digoxigen-in-labeled whole genomic DNA probe and a polymerase chain reaction (PCR) assay based on 16S rRNA species-specific primers (5'-ATG GTG ATT CCG CAT GGT TTC TCC-3'(base position, 188-212) and 5'-CAA ACT TTC ACA GCT GAC TTA AGC-3'(592-615)). Subgingival specimens obtained by paper points from 3 deep periodontal pockets in each of 113 adults were examined. The DNA probe reacted with all pure isolates tested of B. heparinolyticus and did not react with other oral species tested; the probe showed positive reactions in 74.3% of the patient samples examined. The PCR primers produced the 428 bp species specific amplification product in all B. heparinolyticus test strains and did not reveal detectable amplicons with strains of other subgingival species. The PCR method detected 50 B. heparinolyticus cells dispersed in subgingival plaque. PCR only revealed B. heparinolyticus in 6.2% of the patient samples studied. The higher level of positive specimens with the DNA probe was probably due to false-positive reactions from cross-hybridization with unknown subgingival species. This study suggests that the PCR method amplifying specific 16S rRNA sequences represents an easy and valuable means to detect B. heparinolyticus in subgingival plaque. The low prevalence of subgingival B. heparinolyticus does not incriminate the organism in the etiology of adult periodontitis.  相似文献   
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Abstract. Antibiotic treatment of periodontitis aims at eradicating or controlling specific pathogens. Prime candidates for antibiotic therapy are patients with recently diagnosed active periodontitis or a history of recurrent disease who fail to stabilize following mechanical/surgical therapy. Since a variety of microbes with differing antimicrobial susceptibility profiles may cause periodontitis, selection of antimicrobial agents should be based on proper microbial diagnosis and sensitivity testing, as well as consideration of the patient's medical status. The risk of treating chemotherapeutically solely on the basis of clinical features, radiographic findings or a limited microbiological analysis, is failure to control the pathogens or overgrowth of new pathogens. A review of published papers reveals that appropriate systemic antibiotic therapy may enhance healing in patients with recent or high risk of periodontal breakdown. Systemic antibiotic therapy seems more predictable than topical administration in eradicating periodontal pathogens from deep periodontal pockets. Several promising antimicrobial agents for periodontitis treatment need testing in placebo-controlled, double-blind, randomized clinical trials.  相似文献   
25.
ObjectivesThe aim of this study was to investigate the online assessment feasibility of aortography using videodensitometry in the catheterization laboratory during transcatheter aortic valve replacement (TAVR).BackgroundQuantitative assessment of regurgitation after TAVR through aortography using videodensitometry is simple, reproducible, and validated in vitro, in vivo, in clinical trials, and in “real-world” patients. However, thus far the assessment has been done offline.MethodsThis was a single center, prospective, proof-of-principle, feasibility study. One hundred consecutive patients with aortic stenosis and indications to undergo TAVR were enrolled. All final aortograms were analyzed immediately after acquisition in the catheterization laboratory and were also sent to an independent core laboratory for blinded offline assessment. The primary endpoint of the study was the feasibility of the online assessment of regurgitation (percentage of analyzable cases). The secondary endpoint was the reproducibility of results between the online assessment and the offline analysis by the core laboratory.ResultsPatients’ mean age was 81 ± 7 years, and 56% were men. The implanted valves were either SAPIEN 3 (97%) or SAPIEN 3 Ultra (3%). The primary endpoint of online feasibility of analysis was 92% (95% confidence interval [CI]: 86% to 97%) which was the same feasibility encountered by the core laboratory (92%; 95% CI: 86% to 97%). Reproducibility assessment showed a high correlation between online and core laboratory evaluations (R2 = 0.87, p < 0.001), with an intraclass correlation coefficient of 0.962 (95% CI: 0.942 to 0.975; p < 0.001).ConclusionsThis study showed high feasibility of online quantitative assessment of regurgitation and high agreement between the online examiner and core laboratory. These results may pave the way for the application of videodensitometry in the catheterization laboratory after TAVR. (Online Videodensitometric Assessment of Aortic Regurgitation in the Cath-Lab [OVAL]; NCT04047082)  相似文献   
26.
BACKGROUND: Recent findings have begun to provide a basis for a causal link between herpesviruses and aggressive periodontitis. One theory is that herpesviruses cooperate with specific bacteria in the etiopathogenesis of the disease. This study examined whether the presence of herpesviruses [human cytomegalovirus (HCMV), Epstein-Barr virus (EBV) type 1, herpes simplex virus (HSV) type 1 and 2] is associated with the presence of putative pathogenic bacteria (Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, Campylobacter rectus, Actinobacillus actinomycetemcomitans) in aggressive periodontitis lesions. METHODS: The study included 18 young adults with advanced periodontitis and 16 periodontally healthy subjects from Ankara, Turkey. Subgingival specimens pooled from two sites in each subject were collected by a periodontal curette. Qualitative polymerase chain reaction methodology was used to identify herpesviruses and bacteria. Chi-square tests were employed to determine statistical associations among herpesviruses, bacteria and periodontal disease. RESULTS: HCMV, EBV-1 and HSV-1 were each detected in 72-78% of the aggressive periodontitis patients. HSV-2 occurred in 17% of the periodontitis patients. EBV-1 was detected in one periodontally healthy subject. The study bacteria occurred in 78-83% (P. gingivalis, T. forsythia, C. rectus) and in 44% (P. intermedia, A. actinomycetemcomitans) of the periodontitis samples, and in 0-19% of the samples from healthy periodontal sites. HCMV, EBV-1 and HSV-1 were positively associated with P. gingivalis, P. intermedia, T. forsythia and C. rectus, but not with A. actinomycetemcomitans. HSV-2 was not associated with any test bacteria. CONCLUSIONS: These results support the notion that the clinical outcome of some types of severe periodontal infection depends on the presence of specific herpesviruses and bacterial pathogens. Our findings open the door to testing a variety of hypotheses regarding the deleterious aspects of combined herpesviral-bacterial infections in periodontal sites.  相似文献   
27.
An enzyme-linked immunosorbent assay microplate method was used for measuring levels of antibody specific for the oral serotype of Bacteroides asaccharolyticus (Bacteroides gingivalis) in serum samples obtained from umbilical cords, infants, children, periodontally normal adults, and edentulous adults. Serum from patients with various periodontal diseases, including adult periodontitis, localized juvenile periodontitis, generalized juvenile periodontitis, post-localized juvenile periodontitis, and acute necrotizing ulcerative gingivitis, were also studied. A positive correlation between increase in age and increase in both prevalence and level of specific antibody in the G, A, and M classes of immunoglobulins was observed. This indicates that antibodies reactive with oral B. asaccharolyticus found in up to 84% of normal adults are natural antibodies, presumably with a protective role. Among the patient groups, those with adult periodontitis were found to have levels of immunoglobulin G antibodies to oral B. asaccharolyticus that were five times higher than the antibody levels found in control subjects. The levels of IgG antibodies to this organism in the other patient groups were comparable to the levels found in the control group. However, 50% of the individuals in the generalized juvenile periodontitis group had high levels of immunoglobulin G antibodies to B. asaccharolyticus, suggesting heterogeneity with respect to immune response in these patients. These results indicate that antibodies to oral B. asaccharolyticus (B. gingivalis) occur at low levels in most normal children and adults and that the rise in titer of the specific antibodies of each major class of immunoglobulins parallels the ontogenic change in serum levels of that isotype. In contrast, there is a marked increase in titer of immunoglobulin G antibodies to oral B. asaccharolyticus in the group of patients with adult periodontitis and in patients with the generalized form of juvenile periodontitis.  相似文献   
28.
Serum antibodies to indigenous bacteria in ten beagle dogs were examined over a 7-month period during the development of ligature-induced periodontitis. Gram-negative strains comprised approximately 75% of the cultivable periodontitis microflora with a predominance of black-pigmented Bacteroides species. A total of 44 bacterial strains representing the predominant cultivable subgingival beagle dog microflora was selected for antibody determination. The IgG and, in some cases, IgM serum antibody titers to these organisms were determined by indirect immunofluorescence. The antibody titers to most test strains remained unchanged during the experimental period. Gram-negative bacteria generally exhibited lower titers than the Gram-positive bacteria. Especially low titers were found for the black-pigmented Bacteroides. Four dogs that developed the most severe periodontitis showed about 2-fold higher IgG titers to some Gram-negative anaerobic rods in the pre-ligation period than dogs that developed a more moderate periodontitis. These data suggested a possible diagnostic value of such antibody determinations. However, the overall finding of the present study was that serum antibody titers to key periodontopathic organisms remained low throughout the experiment. This result may suggest that the rapid periodontal destruction in ligature-induced periodontitis is due in part to an inadequate antibody response against the infecting microorganisms and their pathogenic products.  相似文献   
29.
Microbiological study of localized juvenile periodontitis in Panama   总被引:2,自引:0,他引:2  
The occurrence of subgingival Actinobacillus actinomycetemcomitans and Capnocytophaga in 12 localized juvenile periodontitis and 10 gingivitis patients from Panama was determined using selective culture techniques. A actinomycetemcomitans was present in all localized juvenile periodontitis lesions studied and was, on average, recovered in hundred-fold-higher numbers from localized juvenile periodontitis lesions than from gingivitis lesions. Capnocytophaga was only recovered in approximately threefold-higher numbers from localized juvenile periodontitis than from gingivitis. The study confirms and extends previous data indicating a close relationship between A actinomycetemcomitans and localized juvenile periodontitis. It is proposed that identification of A actinomycetemcomitans may be a valuable adjunct in the diagnosis of localized juvenile periodontitis.  相似文献   
30.
Macaca arctoides monkeys develop periodontal disease, and they harbor a periodontopathic indigenous flora largely similar to that of humans. This study showed that various Haemophilus isolates and H2O2-splitting asaccharolytic Bacteroides melaninogenicus strains constituted major segments of the monkey periodontal microflora. These organisms have not been previously identified among human isolates. Furthermore, the present data revealed that asaccharolytic B. melaninogenicus strains increased in proportion from a few percent to about 66% of the total isolates concomitant with the development of a significant loss of alveolar bone mass. Hence, this study strongly implicates B. melaninogenicus subsp. asaccharolyticus and closely related strains as important pathogens in actively destructive periodontal disease.  相似文献   
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