Biomedical subjects

A Amano

Publications and source records attributed to A Amano.

At least 19 recordsLinked to original sources

PubMed2006

Relationship of periodontal bacteria and Porphyromonas gingivalis fimA variations with phenytoin-induced gingival overgrowth.

OBJECTIVES: We investigated the relationship between phenytoin-induced gingival overgrowth (GO) and the harboring of periodontal bacteria. MATERIALS AND METHODS: Periodontal conditions and subgingival bacterial profiles were examined in 450 sites of 75 subjects. A polymerase chain reaction method was used to detect six bacterial species; Porphyromonas gingivalis (Pg), Actinobacillus actinomycetemcomitans (Aa), Tannerella forsythia, Treponema denticola (Td), Prevotella intermedia (Pi), and Prevotella nigrescens (Pn). Genetic variations of the Pg fimA gene were also examined. Bacterial occurrence was compared with the severity of GO, and alterations in the bacterial occurrence rate and quantities were monitored following periodontal treatment. RESULTS: The occurrences of Aa, Td, Pi, Pn, and Pg with type II fimA (type II Pg) were significantly associated with the severity of GO. Td occurrence was reduced in association with gingival improvement following ultrasonic scaling, however, no such relationship was observed with Aa, Pi, Pn, and Pg. In addition, Pg and Pi markedly persisted after treatment. Clinical improvement of the sites, following an Er:YAG laser treatment, significantly associated with quantitative reduction of Pg in improved sites, however, not that of Pi. CONCLUSION: Type II Pg and Td were each found to have a significant relationship with the development and deterioration of GO.

Adolescent↗

PubMed2006

Effect of phenytoin on collagen accumulation by human gingival fibroblasts exposed to TNF-alpha in vitro.

OBJECTIVE: Tumor necrosis factor (TNF)-alpha is associated with chronic gingival inflammation and reported to induce gingival overgrowth (GO), while phenytoin (PHT) is also known to be a causative agent of GO. We examined the synergistic effect of PHT and TNF-alpha on collagen metabolism in human gingival fibroblasts (HGFs). MATERIALS AND METHODS: HGFs were cultured with TNF-alpha and PHT. Quantitative real-time RT-PCR was employed to determine the mRNA levels for collagen, matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs) and integrin subunits. Cellular collagen endocytosis was determined using a flow-cytometry. RESULTS: The proliferation of HGFs was not affected by TNF-alpha or PHT individually, whereas both synergistically increased collagen accumulation in HGFs. Further, collagen mRNA expression was not increased by TNF-alpha or PHT, although together they markedly prevented cellular collagen endocytosis, associated with the suppression of alpha2beta1-integrin mRNA expression. The mRNA expression of MMP-1 and-2 was suppressed by PHT, while TIMP-1 mRNA expression was enhanced by both TNF-alpha and PHT. CONCLUSION: Our results suggest that TNF-alpha and PHT together cause impaired collagen metabolism by suppression of enzymatic degradation with MMPs/TIMP-1 and integrin-mediated endocytosis. These synergistic effects may also be involved in TNF-alpha- and PHT-induced collagen accumulation, leading to GO.

Anticonvulsants↗

PubMed2005

The human relaxin receptor (LGR7): expression in the fetal membranes and placenta.

The relaxin receptor has been recently described as a leucine-rich repeat G-protein coupled receptor and designated as LGR7. A closely related receptor, LGR8, is co-expressed by some cells. This study explored the expression of the genes for these receptors in the human fetal membranes and placenta by RT-PCR and the LGR7 protein by immunolocalization. The results showed that LGR7 was well expressed in the fetal membranes, with significantly more in the decidua (p<0.05) than in the amnion. On the other hand, relatively low levels were expressed in the placenta. The major splice variant of LGR7 was undetectable in either the placenta or fetal membranes. Expression of LGR8 was also below the level of detectability in either tissue. Immunostaining for LGR7 was conducted with antisera to both its endodomain and ectodomain, in order to seek evidence for a solubilized ectodomain. However, similar staining patterns were obtained with both antisera, with predominant staining in the cells of the amniotic epithelium, chorionic cytotrophoblast and decidua. Full-thickness fetal membranes from preterm deliveries, before and after labor or after preterm premature rupture of the membrane (PPROM) and labor were collected. In addition, membranes at term, both before and after spontaneous labor were used for analysis of LGR7 gene expression. There was significantly greater LGR7 expressed (p=0.01) in the preterm period compared to term, indicating a potentially important role for relaxin at this time. There was a marginal decline in LGR7 gene expression after labor and delivery both at preterm and term, which did not reach significance. Immunostaining patterns showed less inter-patient variability than did gene expression, with more intense staining for LGR7 after labor and delivery.

Adult↗

PubMed2005

[Graft selection in elderly patients undergoing isolated coronary artery revascularization].

Several studies have shown that off-pump coronary artery bypass (OPCAB) in elderly patients is better in terms of postoperative complications and length of hospital stay. We evaluated the outcomes of isolated OPCAB in octogenarians. From June 2002 to December 2004, 26 patients underwent isolated coronary artery bypass grafting (CABG). All patients underwent OPCAB. These included 4 emergency cases and 12 in an urgent situation, so the overall non-elective rate was 61.5%. There was no hospital death or serious complication. The mean number of grafts per patient was 3.2 +/- 1.6, and the complete revascularization rate was 90.4%. All patients received at least 1 arterial conduit, and 16 patients (61.5%) received all arterial grafts. Saphenous vein grafts were used in 10 patients. These values were not significantly different from those in patients in their 70s who underwent CABG during the same period. We conclude that even in high-risk octogenarian patients, with the aid of the off-pump technique, we can safely perform complete revascularization using more arterial conduits with minimal risk.

Aged↗

PubMed2004

Comparison of inflammatory changes caused by Porphyromonas gingivalis with distinct fimA genotypes in a mouse abscess model.

The fimA gene of Porphyromonas gingivalis, encoding fimbrillin (a subunit protein of fimbriae) has been classified into six genotypes (types I-V and Ib). The genotypic variation was previously suggested to be related to the severity of adult periodontitis in the general population. In this study, we compared inflammatory changes caused by bacterial infection to study pathogenic heterogeneity among the different fimA strains in a mouse abscess model. Bacterial suspensions of 13 P. gingivalis strains representing the six fimA types were subcutaneously injected into female BALB/c mice, and serum sialic acid concentrations were assayed as a quantitative host inflammatory parameter. Type II fimA organisms caused the most significant induction of serum sialic acid, as well as other infectious symptoms, followed by types Ib, IV and V. In contrast, types I and III caused weak inflammatory changes. In addition, fimA mutants of type II strains clearly lost their infectious ability. These findings suggest that fimA genotypic variation affects expression of P. gingivalis virulence.

Abscess↗

PubMed2004

Quantitative detection of periodontal pathogens using real-time polymerase chain reaction with TaqMan probes.

Quantitative analysis, with identification of periodontopathic bacteria, is important for the diagnosis, therapeutic evaluation and risk assessment of periodontal disease. We developed a highly sensitive and specific method using real-time polymerase chain reaction (PCR) to detect and quantify six periodontal bacteria: Porphyromonas gingivalis, Tannerella forsythia, Actinobacillus actinomycetemcomitans, Treponema denticola, Prevotella intermedia, and Prevotella nigrescens. Species-specific TaqMan probe/primer sets were designed according to 16S ribosomal RNA gene sequences. Plaque and tongue debris specimens were collected from 10 patients with advanced periodontitis and 10 periodontal healthy individuals and analyzed. All species, except for P. nigrescens, were detected in samples from diseased sites in significantly greater numbers than in those from healthy sites, whereas greater numbers of P. nigrescens were found in the controls. These results suggest that the present real-time PCR method with the designed probe/primer sets enabled sensitive detection of the six periodontal bacteria, and may also assist future microbial studies of periodontal diseases.

Aggregatibacter actinomycetemcomitans↗

PubMed2003

[Procedure and problem for short-term outcomes on off-pump coronary artery bypass grafting].

We performed off-pump coronary artery bypass grafting (CABG) in all cases without reoperation case from July, 2002. Advantage of off-pump CABG versus on-pump CABG which is reduced a number of perioperative complication and early patients recovery was previously demonstrated. In our institute, the mean number of grafts per patients was 4.7 +/- 1.3, and the rate of using arterial grafts was 99.5% in all cases without minimally invasive direct coronary artery bypass (MIDCAB). The mean hospital stay after operation was 10.8 +/- 2.8. It was shorted remarkably in comparison with on-pump CABG; 19.4 +/- 6. Furthermore, sever complication was not occurred in any cases after operation though high risk cases were increased. In the early cases, atrial fibrillation complicated frequently (32%), but using after magnesium sulfate it was remarkably decreased (8.4%). On the other-hand, attention is necessary for the infection caused by the increase of high risk patients. Therefore, we used vancomycin (VCM) at these cases from the viewpoint of prevention. Recently, we performed remnant omental transfer for the sever diabetes mellitus case which was used bilateral internal thoracic artery on CABG. It learned to get the early recovery which was necessary for the off-pump CABG by the above additional treatment.

Antibiotic Prophylaxis↗

PubMed2002

Identification of a new variant of fimA gene of Porphyromonas gingivalis and its distribution in adults and disabled populations with periodontitis.

Porphyromonas gingivalis fimbriae are critical for the promotion of bacterial infection. The fimA gene encoding fimbrillin, a subunit of fimbriae, has been classified into five genotypes (types I to V) based on their nucleotide sequences. Using a fimA type-specific PCR assay, our previous study demonstrated a close relationship between P. gingivalis possessing type II and type IV fimA genes and adult periodontitis. In that study, some clinical specimens were found to be positive for both types I- and II- fimA specific primers, likely due to the coexistence of two clonal types or a single clone of an unknown genotype in the samples. In the present study, we cloned a new variant of the fimA gene, designated as type Ib fimA, from P. gingivalis HG1691. The nucleotide sequence of the cloned fimA gene showed a 97.1% homology with that of type I fimA, indicating it as a clonal variant of type I fimA. Organisms with type Ib fimA were detected in 13.5% of periodontitis patients and in 2.9% of periodontal healthy adults. Statistical analysis revealed a strong relationship between periodontitis and specific fimA types such as type Ib [odds ratio (OR) 6.51], type II (OR 77.8), and type IV (OR 7.54). Moreover, type Ib fimA-organisms were also found to be related to periodontitis in Down's syndrome (OR 1.91) and mentally disabled populations (OR 4.00). These findings suggest that P. gingivalis with type Ib fimA is closely associated with the progression of periodontitis, similar to organisms with type II and IV fimA.

Adult↗

PubMed2001

Off-pump coronary artery bypass. Mid-term results.

OBJECTIVES: Off-pump coronary artery bypass grafting (CABG) on the beating heart has become popular procedure in cardiac surgery and its initial results appeared favorable. We report our early and mid-term results of off-pump CABG performed at Shin-Tokyo Hospital. METHODS: Medical records of patients undergoing off-pump or conventional on-pump CABG from September 1, 1996, to August 31, 1999 were retrospectively reviewed. Patients underwent off-pump CABG were further classified into 2 groups; MIDCAB (Off-pump CABG for single vessel revascularization via a small skin incision) and OPCAB (off-pump CABG mainly approached via midline sternotomy) group. Their preoperative, perioperative, and follow-up data were collected and analyzed. RESULTS: Among a total of 995 cases of CABG, 194 cases were off-pump CABG (male/female 142/52, mean age 66.9). The mean number of distal anastomoses in off-pump CABG was 1.9 +/- 0.9 (1.0 +/- 0.0 in MIDCAB and 2.3 +/- 0.7 in OPCAB), which was significantly fewer than in on-pump CABG (3.6 +/- 1.1), with p < 0.0001. Intubation time (5.3 +/- 5.7 hours in off-pump CABG vs 13.1 +/- 24.2 hours in on-pump CABG), ICU stay (1.7 +/- 1.1 vs 3.2 +/- 3.0 days), and postoperative hospital stay (14.0 +/- 7.9 vs 18.1 +/- 12.1 days) in off-pump CABG were significantly shorter than in on-pump CABG (p < 0.0001). In the off-pump CABG group, there were no in-hospital deaths and 14 major complications, fewer than in on-pump CABG (8 hospital deaths and 114 major complications). Postoperative angiography before hospital discharge was conducted in 80 patients (41.2%) and showed 2 occlusions, giving a graft patency rate of 98.6% in the off-pump group. During follow-up (0.9 +/- 0.6 year) period, there were 5 non-cardiac deaths and 20 cardiac events in the off-pump group. The actuarial survival rate at 36 months was 94.6% for off-pump CABG, showing no significant difference from the rate for conventional CABG patients (95.2% at 36 month, p = NS) The event-free rate was 84.0% at 36 months in off-pump CABG patients; however, which was less favorable than on-pump CABG patients (88.0% at 36 months, p < 0.05). CONCLUSIONS: Both in-hospital and mid-term results for off-pump CABG patients were acceptable. Isolated CABG can thus be safely performed without cardiopulmonary bypass. Advances in coronary stabilization have contributed to these improved results. The observed long-term cardiac events may be related to incomplete revascularization.

Adolescent↗

PubMed2001

Efficacy of off-pump coronary artery bypass grafting for the patients on chronic hemodialysis.

OBJECTIVE: Coronary artery bypass grafting (CABG) under a beating heart is reported to be less invasive and promise earlier recovery. This study was performed to evaluate the efficacy of off-pump CABG in patients with end-stage renal failure. METHODS: Isolated CABG was performed on 40 hemodialysis patients at Shin-Tokyo Hospital Group between September 1, 1993, and December 31, 2000. Among them, off-pump CABG was performed in 16 and on-pump CABG in 24. Their preoperative, perioperative, and follow-up data were retrospectively collected. RESULTS: Patient's demographics and coronary risk factors were similar in off-pump and on-pump groups. The mean number of bypass grafts was 1.9 +/- 1.1 in the off-pump group and 2.8 +/- 1.1 in the on-pump group (P < 0.05). Blood transfusion was significantly less frequent in the off-pump group than in on-pump group. Postoperative complications were more frequently observed in the on-pump group (7.1% off-pump vs 25.0% on-pump). There were two hospital deaths in the on-pump group and none in the off-pump group. Postoperative intubation time, ICU stay, and hospital stay were significantly shorter in the off-pump group than in the on-pump group. Although follow-up period was short (1.1 +/- 0.7 years), no cardiac events occurred in the off-pump group. CONCLUSIONS: Off-pump CABG for hemodialysis patients is safe and useful and it enables early recovery. Postoperative cardiac events were controlled effectively during the short period of follow-up.

Aged↗

PubMed2001

Double-vessel revascularization using a composite graft approached from small left thoracotomy.

Minimally invasive direct coronary artery bypass usually includes single vessel revascularization via a small skin incision. In most cases, the left internal mammary artery has been used for bypassing to the left anterior descending artery, and only single vessel revascularization used to be performed due to the limited operating field. We present 2 cases of successful double-vessel revascularization approached from a left small thoracotomy, using a composite graft of the internal mammary artery and the inferior epigastric artery, anastomosing to the left anterior descending artery and diagonal artery.

Aged↗

PubMed2001

A previous mastectomy does not increase sternal complications after coronary artery bypass grafting regardless of whether an internal mammary artery is used.

A mastectomy for breast cancer may alter the selection of grafts or the postoperative outcomes after coronary artery bypass grafting (CABG). To clarify these points, a retrospective analysis of patients who underwent CABG after a mastectomy was undertaken. A total of 19 mastectomy patients (13 left, 6 right, and 1 bilateral mastectomy) were identified prior to CABG, and their perioperative data as well as late outcomes were examined. The studied group consisted of all females with a mean age of 68.8 +/- 6.2 years. The internal mammary artery (IMA) was used in 14 (73.7%) patients; however, there were no patients in whom bilateral IMAs were harvested. Among these 14 patients, an ipsilateral IMA was harvested in 6 and a contralateral IMA in 8. Alternative grafts were selected in 6 patients. A contralateral IMA or other graft conduits were utilized instead of an ipsilateral IMA. There were no in-hospital deaths or sternal wound complications. With a mean follow-up of 2.6 years, 3 patients died (1 cardiac death and 2 noncardiac deaths) and 1 patient developed angina due to de-novo coronary artery stenosis. In patients who have undergone a previous mastectomy, CABG using a single IMA is considered to be safe. If the IMA has good pulsation and if IMA harvesting is not difficult, even after a mastectomy, it can be used as a graft conduit without increasing the risk of sternal wound complications.

Aged↗

PubMed2001

Coronary artery bypass grafting using the radial artery: midterm results in a Japanese institute.

BACKGROUND: To avoid remote cardiac events associated with graft occlusions, arterial conduits are being increasingly utilized in coronary artery bypass grafting (CABG). The development of antispasmic agents has enabled the use of the radial artery as a graft conduit in CABG. METHODS: Between December 1995 and December 1998, 920 consecutive isolated CABG operations were performed at Shin-Tokyo Hospital. The radial artery was used for graft conduits in 475 of these patients, and their data were analyzed in this study. The patients were followed to determine midterm graft patency, cardiac events, and survival. All data are given as mean +/- standard deviation. The end points were patient death or occurrence of cardiac events. RESULTS: The radial artery was used in 475 patients (366 males and 109 females, with a mean age of 64.5+/-8.5 years). The left internal mammary artery was used in 94.9% of patients, the right internal mammary artery in 17.5%, the gastroepiploic artery in 50.9%, the inferior epigastric artery in 0.2%, and the saphenous vein in 39.2%. The in-hospital morbidity and mortality rates of the studied group were 12.8% and 0.6%, respectively. A major complication related to radial artery harvesting, compartment syndrome of the arm due to postoperative bleeding, was observed in 1 patient. No postoperative myocardial infarction attributable to radial artery bypass was observed. During the late follow-up period of 3.5+/-0.9 years, cardiac events were observed in 63 patients, giving actuarial 2- and 3-year event-free rates of 92.8% and 89.6%, respectively. A total of 24 late deaths were noted, including seven cardiac deaths, giving actuarial 2- and 3-year survival rates of 98.1% and 97.2%, respectively. Postoperative angiography was performed in selected patients. The cumulative graft patency rate of the radial artery was 93.0% during the mean angiographical follow-up period of 1.5+/-1.1 years. CONCLUSIONS: No adverse effects were noted after CABG using a radial artery graft in this short- and midterm follow-up period.

Actuarial Analysis↗

PubMed2001

Off-pump coronary artery bypass grafting for elderly patients.

BACKGROUND: The use of off-pump coronary artery bypass grafting (CABG) has recently become widespread, and it has been proven to be less invasive and to facilitate early recovery. In this study, we investigated the efficacy of off-pump CABG for patients aged 75 years or more. METHODS: A retrospective chart review was carried out for patients who underwent isolated off-pump and on-pump CABG at Shin-Tokyo Hospital between January 1997 and December 2000. The patients' demographic, operative data, and postoperative results were collected. RESULTS: The off-pump group consisted of 60 men and 44 women with a mean age of 78.8 years, and the on-pump group consisted of 54 men and 20 women with a mean age of 77.6 years. Distal anastomoses were significantly fewer in the off-pump group (2.4 in off-pump group versus 3.7 in on-pump group), but total arterial bypass was more frequently achieved in off-pump group (82.7% versus 25.7%). Intubation time (8.4 versus 18.4 hours), intensive care unit stay (2.2 versus 3.5 days), and postoperative stay (13.8 versus 20.0 days) were significantly shorter in the off-pump group than in the on-pump group (p < 0.05). The frequency of the occurrence of major complications was significantly lower in the off-pump group than the on-pump group, especially in regard to postoperative stroke and respiratory failure (p < 0.05). Multivariate analysis showed that off-pump CABG significantly reduced patient recovery period and the incidence of postoperative complications. Early follow-up results, cardiac event-free and survival rates, did not significantly differ between the two groups. CONCLUSIONS: Off-pump CABG is safe for the elderly patient. Off-pump CABG successfully facilitates early recovery and reduces the incidence of postoperative complications among elderly patients.

Aged↗

PubMed2001

Coronary artery bypass grafting for patients with non-dialysis-dependent renal dysfunction (serum creatinine > or =2.0 mg/dl).

INTRODUCTION: Patients with renal dysfunction carry a risk of coronary atherosclerosis. The purpose of this study was to evaluate the outcome after coronary artery bypass grafting (CABG) in patients with decreased renal function (serum creatinine > or =2.0 mg/dl). METHODS: We retrospectively analyzed consecutive patients who had undergone isolated CABG at Shin-Tokyo Hospital between May 1, 1991 and April 31, 2000. Preoperative, perioperative, and follow-up data of the non-dialysis-dependent patients with preoperative serum creatinine equal to or more than 2.0mg/dl (group R, n=59) were collected, and compared with those of the control patients (serum creatinine < 2.0, group C, n=1666). Group R was further divided into the off-pump and on-pump CABG group and their perioperative results were compared. RESULTS: Group R included 51 males and eight females with a mean age of 66.4. The mean number of anastomoses was not significantly different between groups; however, clump time and pump time were longer in group R. Postoperative recovery was longer in group R than in group C, which is associated with a more frequent occurrence of major complications (28.8% in group R and 10.7% in group C, P<0.0001) and mortalities (6.8% in group R and 0.5% in group C, P<0.0005). The patients who underwent off-pump CABG experienced relatively faster recovery than those who underwent on-pump CABG, despite decreased renal function. At the mean follow-up of 2.4 years, the actuarial 3-year survival rate of groups R and C were 75.3 and 96.9%, respectively (P<0.0001), excluding hospital mortality. The actuarial 3-year cardiac event-free rate was 76.7% in group R and 87.3% in group C (P<0.05). CONCLUSIONS: Patients with decreased renal function carry significant operative risks and require prolonged hospital care. Even after adequate surgical revascularization was completed, the long-term cardiac event-free and survival rates in the patients with renal dysfunction were inferior to the patients with normal renal function.

Adolescent↗

PubMed2001

Altered antigenicity in periodontitis patients and decreased adhesion of Porphyromonas gingivalis by environmental temperature stress.

Periodontopathogenic bacteria survive various environmental changes during the progression of periodontal disease. Alterations in metabolism and protein expression will have to take place to adapt their physiological functions to environmental stress. We examined the effects of an elevation of 2 degrees C in temperature on the adhesive ability and antigenicity of Porphyromonas gingivalis. Elevation of growth temperature of P. gingivalis from 37 degrees C to 39 degrees C remarkably suppressed the expression of surface filamentous structures, such as fimbriae, as well as the adhesive capacities to salivary components and Streptococcus oralis. Sera of severe periodontitis patients revealed a marked increase in serological activity with 39 degrees C cells than with 37 degrees C cells. The alteration of protein profiles of bacterial surface components by temperature elevation was demonstrated by SDS-PAGE, and their Western blot profiles were also different from those of cells grown at 37 degrees C. Although a uniform trend was not found in the altered patterns, sera from severe periodontitis patients detected more antigenic proteins in cells grown at 39 degrees C than 37 degrees C cells. These observations suggest that P. gingivalis downregulates the expression of fimbriae and alters its adhesive capacity and antigenicity by the temperature stress that could occur during the disease progression.

Adaptation, Physiological↗

PubMed2001

Specific antibodies to Porphyromonas gingivalis Lys-gingipain by DNA vaccination inhibit bacterial binding to hemoglobin and protect mice from infection.

Lys-gingipain (KGP), a lysine-specific cysteine proteinase, is one of the major virulence factors of Porphyromonas gingivalis. Here we examined the involvement of the catalytic domain of KGP (KGP(cd)) in hemoglobin binding by P. gingivalis, using a specific immunoglobulin G (IgG) elicited by the administration of plasmid DNA encoding KGP(cd) or the catalytic domain of Arg-gingipain (RGP(cd)). The pSeq2A/kgp(cd) and pSeq2B/rgp(cd) plasmids were constructed by the ligation of kgp(cd) and rgp(cd) DNA fragments, respectively. Female BALB/c mice were immunized with each of these plasmids. pSeq2A/kgp(cd) elicited a strong response to recombinant KGP(cd) (rKGP(cd)), as well as to comparably produced rRGP(cd)-reactive antibodies. The serum antibodies elicited by pSecTag2B/rgp(cd) also cross-reacted with rKGP(cd) as well as rRGP(cd). Anti-KGP(cd) IgG significantly inhibited hemoglobin binding by P. gingivalis. Furthermore, the inhibition of hemoglobin binding was markedly enhanced by a combination of anti-KGP(cd) and anti-fimbriae. Anti-RGP(cd) IgG showed a negligible inhibitory effect, while both anti-KGP(cd) and anti-RGP(cd) IgGs showed significant inhibitory effects on Lys- and Arg-specific proteolytic activities and on the growth of P. gingivalis under iron-restricted conditions where supplemented hemoglobin was the sole iron source. Immunized mice were challenged by intraperitoneal inoculation with P. gingivalis. All nonimmunized mice died within 72 h; however, vaccination with pSeq2A/kgp(cd) and pSeq2B/rgp(cd) prevented inflammatory responses and prolonged the survival rate of immunized mice by 43 and 27%, respectively. These results suggest that KGP(cd) acts as a hemoglobin-binding protein and can also be useful as an immunogen inducing a protective response to P. gingivalis infection.

Adhesins, Bacterial↗

PubMed2001

Relationship of periodontopathic bacteria with early-onset periodontitis in Down's syndrome.

BACKGROUND: Down's syndrome (DS) patients often develop severe early-onset marginal periodontitis in early adulthood; however, there is little information available on the microbiology of DS periodontitis. METHODS: Subgingival plaque specimens were taken from 67 DS young adults and 41 age-matched systemically healthy individuals with mental disabilities (MD). The prevalence of 10 possible periodontopathic bacterial species, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, Treponema denticola, Prevotella intermedia, Prevotella nigrescens, Capnocytophaga ochracea, Capnocytophaga sputigena, Campylobacter rectus, and Eikenella corrodens, were investigated in their subgingival plaque samples using a polymerase chain reaction method. The detection of P. gingivalis fimA genotypes was also performed in P. gingivalis-positive samples. RESULTS: Although DS subjects generally develop an earlier and more extensive periodontal breakdown than those with MD, no significant differences were observed in the bacterial profiles. The profiles of subjects with periodontitis were significant in DS, but not in MD. The prevalence of P. gingivalis, B. forsythus, and P. intermedia were significant in the DS periodontitis group, compared to DS gingivitis group. Moreover, the occurrence of P. gingivalis with the type II fimA gene was significantly related to periodontitis in both DS and MD, with odds ratios of 6.32 and 12.03, respectively. CONCLUSIONS: These results suggest that early-onset periodontitis in DS is mainly due to the more susceptible host for the causative microbial agents including P. gingivalis with type II fimA.

Adult↗