P1363 Risk factors of severe tricuspid regurgitation after left-sided valve surgery

Background

Tricuspid regurgitation (TR) sometimes deteriorate late after left-sided valve surgery. The recent guidelines recommend tricuspid valve repair at the same time as the left-sided valve surgery. However, little is known about the pathophysiology that leads to severe TR after left-sided valve surgery.

Purpose

To clarify the risk factors of the patients with severe TR after left-sided valve surgery.

Methods

We retrospectively investigated consecutive 526 patients diagnosed as severe TR from January 2004 to December 2018 at our hospital. Clinical background, echocardiographic parameters were evaluated. Demographic information and clinical data (including age, electrocardiograms, type of left-sided valve surgery, underlying valve diseases and history of pacemaker or ICD implantation) were obtained by chart review.

Results

Of the 526 patients with severe TR, 107 patients were after a left-sided valve surgery. Patients developed severe TR at a mean of 14.8 ± 8 years after surgery.The surgical indications were as follows: mitral valve stenosis (74 patients, 69%), mitral valve regurgitation (43 patients, 40%), aortic valve stenosis (37 patients, 35%) and aortic regurgitation (28 patients, 26%), respectively. The mean age at diagnosis of severe TR was 74 ± 10 years and 75 were female (70%). Among those patients, 32 patients (30%) had a tricuspid annuloplasty (TAP) with the first left-sided valve surgery. Ninety-five patients (88%) had atrial fibrillation (AF), 75 patients (70%) were diagnosed as rheumatic heart disease, 64 patients (60%) had pulmonary artery hypertension (PH) and 28 patients (26%) had a permanent pacemaker or ICD implantation.

There were only 12 patients who had severe TR without AF. Eight of 12 patients without AF had PH, and permanent pacemakers were implanted in remaining 4 patients.

Conclusions

Almost all patients with severe TR after left-sided valve surgery present with AF and prevalence of rheumatic heart disease were about 70 percent. These two factors may be one of the important risk factors for severe TR after left-sided valve surgery.

Observation and determination of periodontal tissue profile using optical coherence tomography

BACKGROUND AND OBJECTIVE

Diagnosis is a crucial step in periodontal treatment. The aim of this study was to evaluate the effectiveness of optical coherence tomography (OCT) for observation and determination of periodontal tissue profiles in vivo.

MATERIAL AND METHODS

In experiment 1, refractive indices of purified water, porcine gingiva and human gingiva at 1330 nm were determined for the analysis of OCT images of periodontal tissues. In experiment 2, OCT examination was performed in the midlabial apico-coronal plane of mandibular anteriors in 30 Asian volunteers with healthy gingiva. Sulcus depth was measured on intra-oral photographs taken during probing. In the OCT images, the gingival, epithelial and connective tissue thickness, and the position of alveolar bone crest were determined and finally, the biologic width was measured.

RESULTS

Refractive indices of purified water, porcine gingiva and human gingiva were 1.335, 1.393 and 1.397, respectively. Cross-sectional images of gingival epithelium, connective tissue and alveolar bone were depicted in real-time. The sulcular and junctional epithelium could be visualized occasionally. Laser penetration and reflection were limited to a certain depth with an approximate maximal imaging depth capability of 1.5 mm and OCT images of the periodontal structure were not clear in some cases. The average maximal thickness of gingiva and epithelium and biologic width at the mandibular anteriors were 1.06 ± 0.21, 0.49 ± 0.15 and 2.09 ± 0.60 mm, respectively.

CONCLUSION

OCT has promise for non-invasive observation of the periodontal tissue profile in detail and measurement of internal periodontal structures including biologic width in the anterior region.

Association of NOD2 Mutations with Aggressive Periodontitis

Aggressive periodontitis (AgP) is characterized by rapid alveolar bone destruction and tooth loss early in life, and its etiology remains unclear. To explore the genetic risk factors of AgP, we performed genome-wide single-nucleotide polymorphism genotyping for identity-by-descent mapping and identified 32 distinct candidate loci, followed by whole exome sequencing with 2 pedigrees of AgP consisting of 3 cases and 1 control in 1 family and 2 sibling cases in the other. After variant filtering procedures and validation by targeted Sanger sequencing, we identified 2 missense mutations at 16q12 in NOD2 (p.Ala110Thr and p.Arg311Trp), which encodes nucleotide-binding oligomerization domain protein 2. We further examined 94 genetically unrelated AgP patients by targeted sequencing of NOD2 and found that 2 patients among them also carried the p.Arg311Trp variant. Furthermore, we found 3 additional missense mutations in this gene (p.His370Tyr, p.Arg459Cys, and p.Ala868Thr). These mutations either had not been previously observed or are extremely rare (frequency <0.001) in Asian populations. NOD2 plays a crucial role in innate immunity as an intracellular receptor initiating nuclear factor κB-dependent and mitogen-activated protein kinase-dependent gene transcription. These results demonstrated NOD2 as a novel gene involved in AgP.

Biodegradable gelatin/beta-tricalcium phosphate sponges incorporating recombinant human fibroblast growth factor-2 for treatment of recession-type defects: A split-mouth study in dogs

BACKGROUND AND OBJECTIVE

Tissue engineering by using recombinant human (rh) growth factor technology may offer a promising therapeutic approach for treatment of gingival recession. Fibroblast growth factor-2 (FGF-2) has shown the ability to promote periodontal regeneration. Gelatin/beta-tricalcium phosphate (gelatin/β-TCP) sponges have been developed to control the release of growth factors. The present study evaluated the periodontal regenerative efficacy of rhFGF-2 by comparing gelatin/β-TCP sponges incorporated with rhFGF-2 to the scaffolds alone in artificially created recession-type defects in dogs.

MATERIAL AND METHODS

Critically sized buccal gingival recession defects were surgically created on maxillary canine teeth of five dogs. In each animal, defects were randomized to receive either a gelatin/β-TCP sponge soaked with rhFGF-2 (gelatin/β-TCP/rhFGF-2) or phosphate-buffered saline (gelatin/β-TCP). Eight weeks after surgery, biopsy specimens were obtained and subjected to microcomputed tomography and histological analyses.

RESULTS

Complete root coverage was achieved in both groups. Microcomputed tomography revealed significantly greater new bone volume in the gelatin/β-TCP/rhFGF-2 group. Histologically, both groups achieved periodontal regeneration; however, gelatin/β-TCP/rhFGF-2 sites exhibited more tissue regeneration, characterized by significantly larger amounts of new cementum and new bone. Gelatin/β-TCP sites featured increased long junctional epithelium and connective tissue attachment. In the gelatin/β-TCP/rhFGF-2 sites, new bone exhibited many haversian canals and circumferential lamellae as well as remarkably thick periosteum with blood vascularization and hypercellularity.

CONCLUSION

Within the limitations of this study, rhFGF-2 in gelatin/β-TCP sponges exhibits an increased potential to support periodontal wound healing/regeneration in canine recession-type defects.

Assessing the progression of chronic periodontitis using subgingival pathogen levels: a 24-month prospective multicenter cohort study

BACKGROUND

The diagnosis of the progression of periodontitis presently depends on the use of clinical symptoms (such as attachment loss) and radiographic imaging. The aim of the multicenter study described here was to evaluate the diagnostic use of the bacterial content of subgingival plaque recovered from the deepest pockets in assessing disease progression in chronic periodontitis patients.

METHODS

This study consisted of a 24-month investigation of a total of 163 patients with chronic periodontitis who received trimonthly follow-up care. Subgingival plaque from the deepest pockets was recovered and assessed for bacterial content of Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans using the modified Invader PLUS assay. The corresponding serum IgG titers were measured using ELISA. Changes in clinical parameters were evaluated over the course of 24 months. The sensitivity, specificity, and prediction values were calculated and used to determine cutoff points for prediction of the progression of chronic periodontitis.

RESULTS

Of the 124 individuals who completed the 24-month monitoring phase, 62 exhibited progression of periodontitis, whereas 62 demonstrated stable disease. The P. gingivalis counts of subgingival plaque from the deepest pockets was significantly associated with the progression of periodontitis (p < 0.001, positive predictive value = 0.708).

CONCLUSIONS

The P. gingivalis counts of subgingival plaque from the deepest pockets may be associated with the progression of periodontitis.

Preferential changes of skeletal muscle echogenicity in myotonic dystrophy type 1

BACKGROUND AND PURPOSE

In myotonic dystrophy type 1 (DM1), weakness of distal limb muscles affects quality of life. Non-invasive evaluation of muscular involvement by muscle sonography could be useful for characterizing muscle-specific involvement.

METHODS

Sonography of the lower leg and forearm was performed in 19 patients with DM1 and 10 control subjects. The mean echo intensities (EIs) of seven limb muscles were obtained by computer-assisted histogram analysis and compared within DM1 according to the overall clinical severity.

RESULTS

The EIs of the muscles were significantly higher in DM1 than in the controls (P < 0.01), except for the soleus (P = 0.4). Comparison of adjacent muscles showed the following: (i) greater EIs in flexor digitorum profundus than flexor carpi ulnaris (P < 0.01) and flexor digitorum superficialis (P = 0.02), and (ii) greater EIs in the medial head of the gastrocnemius than the soleus (P < 0.00001). In a subgroup analysis of DM1 according to the modified Rankin Scale (mRS), the more severe subgroup (mRS = 4-5) had lower mean EIs than the less severe subgroup (mRS from 1-3) (P = 0.01) in the flexor digitorum superficialis but not in other muscles.

CONCLUSIONS

Preferential high echogenicity in the medial gastrocnemius and deep finger flexors is suggestive of DM1. Muscle echogenicity is not generally related to functional dysfunction in DM1.

Development of fast neutron pinhole camera using nuclear emulsion for neutron emission profile measurement in KSTAR

We have developed a compact fast neutron camera based on a stack of nuclear emulsion plates and a pinhole collimator. The camera was installed at J-port of Korea superconducting tokamak advanced research at National Fusion Research Institute, Republic of Korea. Fast neutron images agreed better with calculated ones based on Monte Carlo neutron simulation using the uniform distribution of Deuterium-Deuterium (DD) neutron source in a torus of 40 cm radius.

Emergence of Epstein-Barr virus-associated haemophagocytic syndrome upon treatment of systemic lupus erythematosus

A 32-year-old female patient with systemic lupus erythematosus was admitted to our hospital with fever and cytopenia, and diagnosed as haemophagocytic syndrome (HPS) by bone marrow aspiration study showing haemophagocytosis. Since the serologic activity of lupus was not increased at that time and HPS was refractory to the conventional therapies, an additional aetiological factor was suspected. Real-time PCR analysis identified reactivation of Epstein-Barr virus (EBV). A combination therapy targetting EBV-associated HPS, consisting of intravenous administration of cyclosporine A as well as immunoglobulin with a high titre of anti-EBV antibody, significantly suppressed EBV viraemia and led to the remission of HPS until the time of writing.

Bone metabolic microarray analysis of ligature-induced periodontitis in streptozotocin-induced diabetic mice

BACKGROUND AND OBJECTIVE

Periodontal disease is a chronic infectious disease that results in bone loss. Many epidemiological studies have reported the progression of periodontal tissue destruction in patients with diabetes; however, the associated mechanism remains unclear. In this study, we comprehensively investigated how diabetes affects the periodontal tissue and alveolar bone loss using a ligature-induced periodontitis model in streptozotocin-induced diabetic (STZ) mice.

MATERIAL AND METHODS

Diabetes was induced by intraperitoneal injection with streptozotocin in 6-wk-old C57/BL6J male mice. A silk ligature was tied around the maxillary left second molar in 9-wk-old wild-type (WT) and STZ mice. Bone loss was evaluated at 3 and 7 d after ligation. mRNA expression levels in the gingiva between the two groups were examined by DNA microarray and quantitative polymerase chain reaction at 1, 3 and 7 d post-ligation. Tartrate-resistant acid phosphatase and alkaline phosphatase staining of the periodontal tissue was performed for evaluation of osteoclasts and osteoblasts in histological analysis.

RESULTS

In the gingiva, hyperglycemia upregulated the osteoprotegerin (Opg) mRNA expression and downregulated Osteocalcin mRNA expression. In the ligated gingiva, tumor necrosis factor-α (Tnf-α) mRNA expression was upregulated at 1 d post-ligation in STZ mice but not in WT mice. At 3 d post-ligation, alveolar bone loss was observed in STZ mice, but not in WT mice. Significantly severe alveolar bone loss was observed in STZ mice compared to WT mice at 7 d post-ligation. Bone metabolic analysis using DNA microarray showed significant downregulation in the mRNA expression of glioma-associated oncogene homologue 1 (Gli1) and collagen type VI alpha 1 (Col6a1) at the gingiva of the ligated site in STZ mice compared to that in WT mice. Quantitative polymerase chain reaction showed that Gli1 and Col6a1 mRNA expression levels were significantly downregulated in the gingiva of the ligated site in STZ mice compared to WT mice. Histological analysis showed lower alkaline phosphatase activity in STZ mice. In addition, an increased number of tartrate-resistant acid phosphatase-positive multinucleated cells were observed at the ligated sites in STZ mice.

CONCLUSIONS

These results suggest that an imbalance of bone metabolism causes osteoclastosis in insulin-deficient diabetes, and that alveolar bone loss could occur at an early phase under this condition.

Salivary pathogen and serum antibody to assess the progression of chronic periodontitis: a 24-mo prospective multicenter cohort study

BACKGROUND AND OBJECTIVE

A diagnosis of periodontitis progression is presently limited to clinical parameters such as attachment loss and radiographic imaging. The aim of this multicenter study was to monitor disease progression in patients with chronic periodontitis during a 24-mo follow-up program and to evaluate the amount of bacteria in saliva and corresponding IgG titers in serum for determining the diagnostic usefulness of each in indicating disease progression and stability.

MATERIAL AND METHODS

A total of 163 patients with chronic periodontitis who received trimonthly follow-up care were observed for 24 mo. The clinical parameters and salivary content of Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans were assessed using the modified Invader PLUS assay, and the corresponding serum IgG titers were measured using ELISA. The changes through 24 mo were analyzed using cut-off values calculated for each factor. One-way ANOVA or Fisher's exact test was used to perform between-group comparison for the data collected. Diagnostic values were calculated using Fisher's exact test.

RESULTS

Of the 124 individuals who completed the 24-mo monitoring phase, 62 exhibited periodontitis progression, whereas 62 demonstrated stable disease. Seven patients withdrew because of acute periodontal abscess. The ratio of P. gingivalis to total bacteria and the combination of P. gingivalis counts and IgG titers against P. gingivalis were significantly related to the progression of periodontitis. The combination of P. gingivalis ratio and P. gingivalis IgG titers was significantly associated with the progression of periodontitis (p = 0.001, sensitivity = 0.339, specificity = 0.790).

CONCLUSIONS

It is suggested that the combination of P. gingivalis ratio in saliva and serum IgG titers against P. gingivalis may be associated with the progression of periodontitis.

The identification of raft-derived tau-associated vesicles that are incorporated into immature tangles and paired helical filaments

AIMS

Neurofibrillary tangles (NFTs), a cardinal pathological feature of neurodegenerative disorders, such as Alzheimer's disease (AD) are primarily composed of hyper-phosphorylated tau protein. Recently, several other molecules, including flotillin-1, phosphatidylinositol-4,5-bisphosphate [PtdIns(4,5)P2] and cyclin-dependent kinase 5 (CDK5), have also been revealed as constituents of NFTs. Flotillin-1 and PtdIns(4,5)P2 are considered markers of raft microdomains, whereas CDK5 is a tau kinase. Therefore, we hypothesized that NFTs have a relationship with raft domains and the tau phosphorylation that occurs within NFTs.

METHODS

We investigated six cases of AD, six cases of other neurodegenerative diseases with NFTs and three control cases. We analysed the PtdIns(4,5)P2-immunopositive material in detail, using super-resolution microscopy and electron microscopy to elucidate its pattern of expression. We also investigated the spatial relationship between the PtdIns(4,5)P2-immunopositive material and tau kinases through double immunofluorescence analysis.

RESULTS

Pretangles contained either paired helical filaments (PHFs) or PtdIns(4,5)P2-immunopositive small vesicles (approximately 1 μm in diameter) with nearly identical topology to granulovacuolar degeneration (GVD) bodies. Various combinations of these vesicles and GVD bodies, the latter of which are pathological hallmarks observed within the neurons of AD patients, were found concurrently in neurons. These vesicles and GVD bodies were both immunopositive not only for PtdIns(4,5)P2, but also for several tau kinases such as glycogen synthase kinase-3β and spleen tyrosine kinase.

CONCLUSIONS

These observations suggest that clusters of raft-derived vesicles that resemble GVD bodies are substructures of pretangles other than PHFs. These tau kinase-bearing vesicles are likely involved in the modification of tau protein and in NFT formation.

Ridge augmentation using recombinant human fibroblast growth factor-2 with biodegradable gelatin sponges incorporating β-tricalcium phosphate: a preclinical study in dogs

BACKGROUND AND OBJECTIVE

Fibroblast growth factor-2 (FGF-2) regulates the proliferation and differentiation of osteogenic cells, resulting in the promotion of bone formation. Biodegradable gelatin sponges incorporating β-tricalcium phosphate (β-TCP) have been reported as a scaffold, which has the ability to control growth factor release, offering sufficient mechanical strength and efficient migration of mesenchymal cells. In this study, we evaluated the effects of the combined use of recombinant human FGF-2 (rhFGF-2) and gelatin/β-TCP sponge on ridge augmentation in dogs.

MATERIAL AND METHODS

Six male beagle dogs were used in this study. Twelve wk after tooth extraction, bilateral 10 × 5 mm (width × depth) saddle-type defects were created 3 mm apart from the mesial side of the maxillary canine. At the experimental sites, the defects were filled with gelatin/β-TCP sponge infiltrated with 0.3% rhFGF-2, whereas gelatin/β-TCP sponge infiltrated with saline was applied to the control sites. Eight wk after surgery, qualitative and quantitative analyses were performed.

RESULTS

There were no signs of clinical inflammation at 8 wk after surgery. Histometric measurements revealed that new bone height at the experimental sites (2.98 ± 0.65 mm) was significantly greater than that at the control sites (1.56 ± 0.66 mm; p = 0.004). The total tissue height was greater at the experimental sites (6.62 ± 0.66 mm) than that at the control sites (5.95 ± 0.74 mm), although there was no statistical significant difference (p = 0.051). Cast model measurements revealed that the residual defect height at the experimental sites (2.31 ± 0.50 mm) was significantly smaller than that at the control sites (3.51 ± 0.78 mm; p = 0.012).

CONCLUSION

The combined use of rhFGF-2 and gelatin/β-TCP sponge promotes ridge augmentation in canine saddle-type bone defects.

Increased prevalence of MEFV exon 10 variants in Japanese patients with adult-onset Still's disease

Autoinflammatory diseases include a large spectrum of monogenic diseases, e.g. familial Mediterranean fever (FMF), as well as complex genetic trait diseases, e.g. adult-onset Still's disease (AOSD). In populations where FMF is common, an increased MEFV mutation rate is found in patients with rheumatic diseases. The aim of this study was to examine MEFV mutations in Japanese patients with AOSD. Genomic DNA was isolated from 49 AOSD patients and 105 healthy controls, and exons 1, 2, 3 and 10 of the MEFV gene genotyped by direct sequencing. MEFV mutation frequencies in AOSD patients were compared with controls. We found no significant difference in overall allele frequencies of MEFV variants between AOSD patients and controls. However, MEFV exon 10 variants (M694I and G632S) were significantly higher in AOSD patients than controls (6.1 versus 0%). In addition, there was no significant difference between MEFV variant carriers and non-carriers with clinical manifestations, but the monocyclic clinical course of the AOSD disease phenotype was observed less frequently in patients without MEFV variants. AOSD patients had significantly higher frequencies of MEFV exon 10 mutations, suggesting that low-frequency variants of MEFV gene may be one of the susceptibility factors of AOSD.

A Genome-wide Association Study of Periodontitis in a Japanese Population

Periodontitis is a multifactorial disease in which bacterial, lifestyle, and genetic factors are involved. Although previous genetic association studies identified several susceptibility genes for periodontitis in European populations, there is little information for Asian populations. Here, we conducted a genome-wide association study and a replication study consisting of 2,760 Japanese periodontitis patients and 15,158 Japanese controls. Although single-nucleotide polymorphisms that surpassed a stringent genome-wide significance threshold ( P < 5 × 10−8) were not identified, we found 2 suggestive loci for periodontitis: KCNQ5 on chromosome 6q13 (rs9446777, P = 4.83 × 10−6, odds ratio = 0.82) and GPR141-NME8 at chromosome 7p14.1 (rs2392510, P = 4.17 × 10−6, odds ratio = 0.87). A stratified analysis indicated that the GPR141-NME8 locus had a strong genetic effect on the susceptibility to generalized periodontitis in Japanese individuals with a history of smoking. In conclusion, this study identified 2 suggestive loci for periodontitis in a Japanese population. This study should contribute to a further understanding of genetic factors for enhanced susceptibility to periodontitis.