Posterior wall thickness of the confluent inferior pulmonary veins measured by left atrial intracardiac echocardiography: implications for catheter ablation

BACKGROUND

Confluent inferior pulmonary veins (CIPV) is a rare anatomical variant. There is few evidence in the literature regarding anatomic landmarks consideration to guide radiofrequency application in avoiding complications in the esophagus in CIPV cases.

METHODS

Of 986 consecutive patients undergoing atrial fibrillation (AF) ablation from July 2020 to June 2022, seven (0.7%) had CIPV with a common trunk connecting to the LA diagnosed by 3-dimensional contrast-enhanced computed tomography. Using intracardiac echocardiography (ICE) performed from the left atrium (LA), we measured the posterior wall thickness (PWT) of the CIPV adjacent to the esophagus and compared the measurement with the LA posterior wall thickness (LAPWT) at the left inferior PV level of 25 controls without CIPV. For ablation in CIPV patients, each superior PV was individually isolated, and box isolation of CIPV without ablating the CIPV posterior wall was added (tri-circle ablation technique).

RESULTS

The CIPV PWT was 0.7 ± 0.1 mm, while non-CIPV LAPWT was 2.0 ± 0.4 mm (P < 0.001). In the CIPV group, upper and lower portions of the CIPV were both apart from the esophagus (mean distances, 6.7 ± 3.4 mm and 7.9 ± 2.7 mm, respectively). Individual superior PV isolation and box CIPV isolation resulted in complete isolation of all PVs, with no complications. All CIPV patients except one remained AF recurrence-free for 376 ± 52 days.

CONCLUSIONS

Although CIPV frequency is low, CIPV PWT is very thin and special care is needed during ablation. A "tri-circle" ablation strategy avoids ablating in the thinnest portion of the posterior wall. Further studies are warranted to assess the safety.

Predictors of pulmonary vein non-reconnection in the second procedure after ablation index-guided pulmonary vein isolation for atrial fibrillation and its impact on the outcome

INTRODUCTION

Although first-pass isolation (FPI) of the pulmonary vein (PV) has been suggested as a marker for PV isolation (PVI) durability, it has not been confirmed. Non-PV atrial fibrillation (AF) triggers were the main target in patients without PV reconnection in the second ablation procedure, but the outcome was unclear. We aimed to validate FPI as a marker of PVI durability and evaluate the outcome after the second procedure in patients without PV reconnection by comparing it to those with reconnection.

METHODS

Among the 2087 patients undergoing the first ablation index-guided radiofrequency AF ablation, 309 with atrial tachyarrhythmias (ATs) recurrence and undergoing the second procedure were studied. Clinical characteristics and outcomes were compared between the patients without PV reconnection (PV non-reconnection group, n = 142) and with reconnection (PV reconnection group, n = 167).

RESULTS

FPI in both PV sides in the first ablation procedure was significantly more frequent in the PV non-reconnection group (77.5%) than in the PV reconnection group (45.5%) (p < .001). Multivariate logistic regression analysis revealed that FPI (odds ratio, 3.71 [95% confidence interval, 2.23-6.19], p < .001) was the only predictor of PV non-reconnection. Radiofrequency applications for non-PV AF triggers were more frequently performed in the PV non-reconnection group (40.8% vs. 24.6%, respectively, p < .001). Kaplan-Meier analysis revealed that AT recurrence-free rate was significantly lower in the PV non-reconnection group (1-year recurrence-free rate, 62.7% vs. 75.4%, respectively; p = .01 by log-rank test).

CONCLUSION

FPI was the only independent predictor of PV non-reconnection. Despite aggressive ablation for non-PV triggers, AT recurrence was more frequent in patients with PV non-reconnection.

Safety and efficacy of ablation index-guided atrial fibrillation ablation in octogenarians

BACKGROUND

Limited data on the efficacy and safety of atrial fibrillation (AF) ablation using an ablation index (AI) for octogenarians is available. We aimed to compare the efficacy and safety of AI-guided AF ablation between AF patients aged ≥80 years (Group 1) and <80 (Group 2).

HYPOTHESIS

We hypothesized that AI-guided AF ablation could complete the procedure with comparable efficiency and safety in patients aged ≥80 years and <80.

METHODS

We retrospectively reviewed 2087 AF patients undergoing their first AI-guided AF ablation in our hospital. We compared the atrial tachyarrhythmia (AT) recurrence and procedure-related complication rate between Group 1 (n = 193) and Group 2 (n = 1894).

RESULTS

The mean age was 83.0 (interquartile range [IQR] 81.0, 84.0) years in Group 1 and 67.0 (IQR 60.0, 72.0) in Group 2. AF type was significantly different between the two groups: Of Group 1 patients, 120 (62.2%) had paroxysmal AF, 61 (31.6%) persistent AF, and 12 (6.2%) long-standing persistent AF, while of Group 2 patients, 1016 (53.6%) paroxysmal AF, 582 (30.7%) persistent AF, and 296 (15.6%) long-standing persistent AF (p = .001). Unadjusted AT recurrence-free survival curves showed similar AT recurrence-free survival between the two groups (p = .67 by log-rank test). After the adjustment for AF type, the survival curve was similar between them (hazard ratio, 1.24; 95% CI [0.92-1.65]; p = .15, Group 1 vs. Group 2). The rate of procedure-related complications was similar between the two groups (3.1% vs. 3.0%, respectively, p = .83).

CONCLUSION

Catheter ablation guided by AI achieved similar AT recurrence and complication rates between elderly AF patients aged ≥80 years and patients <80 years.

Cardio-Ankle Vascular Index and Left Atrial Reverse Remodeling After Ablation for Atrial Fibrillation

Arterial stiffness has been reported to cause left atrial (LA) remodeling due to increased left ventricular filling pressure, resulting in atrial fibrillation (AF). This study aimed to evaluate the association between LA reverse remodeling (LARR) after AF ablation and cardio-ankle vascular index (CAVI), an indicator of arterial stiffness.This study included 333 patients with AF (171 with paroxysmal AF and 162 with nonparoxysmal AF) and LA enlargement (LA volume index ≥ 34 mL/m²) who underwent AF ablation between December 2008 and July 2021. CAVI was evaluated preoperatively during AF (n = 155, 46.5%) or sinus rhythm (n = 178, 53.5%). Participants were divided into groups with LARR (n = 133, 39.9%) and without LARR (n = 200, 60.1%) according to whether the degree of decrease in LA volume index on transthoracic echocardiography 6 months after ablation was ≥ 15% or < 15%, respectively.Sinus rhythm was maintained in 168 (50.5%) patients within 3-6 months after the index procedure. Univariate analysis revealed that preoperative CAVI (7.80 ± 1.22 versus 8.57 ± 1.09, P < 0.001) was significantly lower, and the maintenance of sinus rhythm (61.6% versus 43.0%, P = 0.0011) was higher in the group with LARR. Multivariate logistic regression analysis revealed that preoperative CAVI was independently associated with LARR (odds ratio, 0.60, 95% confidence interval, 0.46-0.78, P < 0.001).In patients with AF and LA enlargement, CAVI is independently associated with LA reverse remodeling after catheter ablation.

Functional analysis of thermo-sensitive TRPV1 in an aquatic vertebrate, masu salmon (Oncorhynchus masou ishikawae)

Transient receptor potential vanilloid 1 (TRPV1) is mainly expressed in nociceptive primary sensory neurons and acts as a sensor for heat and capsaicin. The functional properties of TRPV1 have been reported to vary among species and, in some cases, the species difference in its thermal sensitivity is likely to be associated with thermal habitat conditions. To clarify the functional properties and physiological roles of TRPV1 in aquatic vertebrates, we examined the temperature and chemical sensitivities of TRPV1 in masu salmon (Oncorhynchus masou ishikawae, Om) belonging to a family of salmonids that generally prefer cool environments. First, behavioral experiments were conducted using a video tracking system. Application of capsaicin, a TRPV1 agonist, induced locomotor activities in juvenile Om. Increasing the ambient temperature also elicited locomotor activity potentiated by capsaicin. RT-PCR revealed TRPV1 expression in gills as well as spinal cord. Next, electrophysiological analyses of OmTRPV1 were performed using a two-electrode voltage-clamp technique with a Xenopus oocyte expression system. Heat stimulation evoked an inward current in heterologously expressed OmTRPV1. In addition, capsaicin produced current responses in OmTRPV1-expressing oocytes, but higher concentrations were needed for its activation compared to the mammalian orthologues. These results indicate that Om senses environmental stimuli (heat and capsaicin) through the activation of TRPV1, and this channel may play important roles in avoiding environments disadvantageous for survival in aquatic vertebrates.

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Capsaicin evoked behavioral responses of Oncorhynchus masou ishikawae (Om).

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The behavioral response to heat was potentiated by capsaicin.

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Heterologously expressed OmTRPV1 was activated by heat and capsaicin.

A case of Takotsubo cardiomyopathy with apical hypertrophic cardiomyopathy-like morphological changes during recovery

Objective: Few cases of Takotsubo cardiomyopathy with apical hypertrophic cardiomyopathy (APH)-like morphological changes during the recovery process have been reported.

Patient: A 56-year-old woman diagnosed with Takotsubo cardiomyopathy showed a morphology similar to that of APH during recovery. We examined this patient using 2D speckle-tracking echocardiography based on the method used for hypertrophic cardiomyopathy, which suggested that the circumferential strain (CS) of the middle wall indicated myocardial function of the left ventricle, and the CS of the inner wall was associated with left ventricular chamber function.

Results: We measured the CS of the endocardial, middle, and epicardial layers and found that the apical inner layer CS (CSinner), middle layer CS, and outer layer CS were all decreased at the onset. CSinner showed a strong tendency to recover on echocardiography performed when APH-like morphology was observed.

Conclusion: The morphology of the apex in our case likely contributed to the maintenance of chamber function.

Prognostic impact of heart mate risk score among elderly heart failure patients with non-responder for cardiac resynchronization therapy

Background

For patients with severe heart failure (HF) who are not eligible for transplantation, there is destination therapy (DT) that uses a continuous flow left ventricular assist device (LVAD). Implantation of LVAD improves HF and can be expected to improve the prognosis of life. Elderly refractory HF patients with non-responders for cardiac resynchronization therapy (CRT) may benefit from LVAD as DT. In considering indications of LVAD as DT for the elderly in Japan, conditions such as a low risk of Heart Mate Risk Score (HMRS) have been raised. HMRS has been shown to correlate with mortality in the cohort of LVAD patients enrolled in the Heartmate II trials.

Purpose

Because elderly CRT non-responder refractory HF patients are not indicated for transplantation and may benefit from LVAD as DT in Japan, we aimed to investigate the HMRS and prognosis among elderly CRT non-responders.

Methods

Of 467 patients underwent CRT implantation between 2000 and 2015, 157 were aged 65–75 years old. Of which 59 patients who could be determined to be non-responders based on echocardiographic data were included in this study. The primary endpoint was all-cause mortality, the secondary was readmission for HF and appropriate implantable cardioverter defibrillator (ICD) therapy.

Results

The patients' mean age was 68 years, males were 71%. The mean serum creatinine value was 1.1 mg/dl, albumin was 3.8 mg/dl, and BNP was 383 pg/ml. The mean left ventricular ejection fraction (LVEF) was 26%. The subjects were divided into 3 groups according to HMRS. The average of HMRS was 2.2, the low-risk group included 17 (29%) patients, the medium was 22 (37%), and the high was 20 (34%). There was no significant difference in age, LVEF, BNP, and NYHA functional classification at the time of CRT implantation between three groups. In the low-risk group, creatinine and INR were significantly lower, and albumin was significantly higher compared to the high-risk group. BNP tended to be lower in the low-risk group, but there was no significant difference. The mortality rate by HMRS was 12% in the low-risk group, 36% in the medium-risk group, and 50% in the high-risk group. On the Kaplan-Meier analysis, the low-risk group had a significantly lower mortality rate than the high-risk group (Figure). Furthermore, focusing on HF readmission, the rate of readmission was 59% in the low-risk group, 86% in the medium -risk group, and 65% in the high-risk group, and there was no significant difference between three groups. There was also no significant difference in appropriate ICD therapy between three groups.

Conclusion

Approximately 30% of elderly non-responders of CRT are in the low-risk group by HMRS and their mortality was lower than that of the other two groups. These elderly CRT non-responder patients might be considered a candidate for DT in Japan.

Funding Acknowledgement

Type of funding sources: None.

Effects of Sulfonylureas on Periodontopathic Bacteria-Induced Inflammation

Interleukin-1β (IL-1β) is an inflammatory cytokine produced by monocytes/macrophages and is closely associated with periodontal diseases. The NLRP3 inflammasome is involved in IL-1β activation through pro-IL-1β processing and pyroptotic cell death in bacterial infection. Recently, glyburide, a hypoglycemic sulfonylurea, has been reported to reduce IL-1β activation by suppressing activation of the NLRP3 inflammasome. Therefore, we evaluated the possibility of targeting the NLRP3 inflammasome pathway by glyburide to suppress periodontal pathogen-induced inflammation. THP-1 cells (a human monocyte cell line) were differentiated to macrophage-like cells by treatment with phorbol 12-myristate 13-acetate and stimulated by periodontopathic bacteria, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, or Fusobacterium nucleatum, in the presence of glyburide. IL-1β and caspase-1 expression in the cells and culture supernatants were analyzed by Western blotting and enzyme-linked immunosorbent assay, and cell death was analyzed by lactate dehydrogenase assay. Stimulation of THP-1 macrophage-like cells with every periodontopathic bacteria induced IL-1β secretion without cell death, which was suppressed by the NLRP3 inhibitor, MCC950, and caspase-1 inhibitor, z-YVAD-FMK. Glyburide treatment suppressed IL-1β expression in culture supernatants and enhanced intracellular IL-1β expression, suggesting that glyburide may have inhibited IL-1β secretion. Subsequently, a periodontitis rat model was generated by injecting periodontal bacteria into the gingiva, which was analyzed histologically. Oral administration of glyburide significantly suppressed the infiltration of inflammatory cells and the number of osteoclasts in the alveolar bone compared with the control. In addition to glyburide, glimepiride was shown to suppress the release of IL-1β from THP-1 macrophage-like cells, whereas other sulfonylureas (tolbutamide and gliclazide) or other hypoglycemic drugs belonging to the biguanide family, such as metformin, failed to suppress IL-1β release. Our results suggest that pharmacological targeting of the NLRP3 pathway may be a strategy for suppressing periodontal diseases.

Genetic and phenotypic profile of 112 patients with X-linked Charcot-Marie-Tooth disease type 1

BACKGROUND AND PURPOSE

X-linked Charcot-Marie-Tooth disease type 1 (CMTX1), caused by mutations in gap junction protein beta 1 (GJB1), is characterized by various central nervous system symptoms and gender differences of clinical severity. The aim of this study was to identify the frequency and mutation spectrum of CMTX1 patients in Japan and to demonstrate their phenotypic diversities.

METHODS

Using three high-throughput sequencing systems, targeted gene panel sequencing on 1483 unrelated index patients with suspected Charcot-Marie-Tooth (CMT) disease was performed. The peripheral and central nervous system involvements of all patients with GJB1 variants were assessed retrospectively and a detailed gender comparison was conducted with the CMT examination score.

RESULTS

Twenty-three novel and 36 described GJB1 variants were identified from 88 pedigrees, in which 34 female and 78 male patients were enrolled. Mean age at onset of the male patients was much younger than the females, 21.56 ± 17.63 years vs. 35.53 ± 23.72 years (P = 0.007). Male patients presented with more severe phenotypes in every examination item, but statistical differences were observed only in motor dysfunctions of the lower extremities and vibration sensation. No significant sensory difference was identified between genders, either clinically or electrophysiologically. Central nervous system dysfunctions were found in 15 patients from 12 pedigrees. Therein, six patients developed stroke-like phenotypes, with dysarthria as the leading symptom.

CONCLUSIONS

A relatively lower frequency of CMTX1 (5.9%) was demonstrated and a broad mutation spectrum of GJB1 was described. Detailed clinical differences between genders and various central nervous system symptoms were also illustrated, even in the same pedigree.

Abstract P2-01-09: Circulating tumor cells (CTCs) in the venous drainage of the breast in patients with primary breast cancer

Background:

CTCs are shed from tumors and circulate in the peripheral blood after passing through the drainage vein. Axillary lymph node dissection (ALND) provides access to the lateral thoracic vein which flows directly into the axillary vein. In this preliminary study, we evaluated the feasibility of detecting CTCs in the peripheral blood and in the lateral thoracic venous blood for breast cancer patients who underwent ALND.

Methods:

From June 2016 to March 2017, breast cancer patients who underwent ALND in our institute were eligible for this study. A peripheral blood sample,10ml, was drawn just before the surgery or one day before the surgery. A lateral thoracic venous blood sample was taken from the resected breast just after resection. A blood sample of 0.2ml or more was necessary for CTC isolation. The CTCs in the peripheral blood before surgery (periCTC) and in the blood from the lateral thoracic vein of the resected breast (ltvCTC) were quantitatively examined by using a size-selective CTC isolation platform.

Results:

A total of 21 patients with median age 51 years (37-75) were enrolled to the study. Of the 21 patients, 38% were premenopausal, 52% had neoadjuvant chemotherapy. Fifty-seven percent were ER and/or PgR positive, 24% were HER2 positive. Fifty-seven percent were stage II disease and 43% were stage III. In 3 patients, we couldn't obtain sufficient blood samples from the lateral thoracic vein. Of the remaining 18 patients, we were able to obtain the median 0.5ml (0.2-2.0) blood samples from the lateral thoracic vein. CTCs were detected in peripheral blood in 15 patients (71%) and median periCTC count was 1 CTC/10ml (0-39). In lateral thoracic venous blood, CTCs were detected in all patients who had sufficient blood samples and the median ltv CTC count was 35.5 CTC/ml (2.5-370). In 5 of 6 patients whom CTCs in peripheral blood samples were not detected, CTCs could be detected in the blood samples from lateral thoracic vein.

Conclusion:

CTCs can be detected in the peripheral blood and in the blood from lateral thoracic vein in patients with localized breast cancer, and can be detected at a higher rate and at a higher concentration in the blood from lateral thoracic vein than in peripheral blood.

Citation Format: Hattori M, Nakanishi H, Yoshimura A, Adachi Y, Iwase M, Gondo N, Kotani H, Sawaki M, Yatabe Y, Iwata H. Circulating tumor cells (CTCs) in the venous drainage of the breast in patients with primary breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-01-09.

Abstract P2-12-13: Withdrawn

This abstract was withdrawn by the authors.

A case of acute coronary syndrome caused by delayed coronary ischemia after transcatheter aortic valve implantation

An 84-year-old female patient suffered from dyspnea due to severe aortic stenosis. Several comorbidities and her advanced age made her acceptable for transcatheter aortic valve implantation (TAVI). The TAVI procedure was performed via a femoral access and a 26-mm CoreValve prosthesis (Medtronic, Minneapolis, MN, USA) was implanted. The prosthesis was deployed at a high position because of short distance between the annulus base and coronary arteries. Aortic angiography indicated normal contrast flow into both coronary arteries. Six months later she was readmitted to our hospital because of acute coronary syndrome. Although selective intubation of coronary arteries could not be achieved because of high valve position, both coronary arteries seemed to be well contrasted. As a consequence, the second coronary angiography was undertaken because of recurring chest pains. The aortic root angiogram showed a decreased contrast flow into both coronary arteries. During the examination she deteriorated rapidly, developed cardiopulmonary arrest, and a percutaneous cardiopulmonary support and an intra-aortic balloon pump needed to be inserted. She was then transferred to the operating room for aortic valve replacement. This is the first case of delayed coronary ischemia after TAVI, necessitating the removal of an implanted CoreValve and its replacement with a new prosthetic valve. <Learning objective: The higher position of the CoreValve implanted in the transcatheter aortic valve implantation (TAVI) procedure can rarely induce coronary obstruction, especially in patients with low lying coronary ostia and a small sinus of Valsalva. Percutaneous coronary intervention and coronary artery bypass graft are sometimes difficult in these patients, and replacement of the prosthetic valve may be an alternative. Patients with higher CoreValve position require close follow up to recognize any coronary perfusion defects at an early stage.>.

Crystalline structure of pulverized dental calculus induces cell death in oral epithelial cells

BACKGROUND AND OBJECTIVE

Dental calculus is a mineralized deposit attached to the tooth surface. We have shown that cellular uptake of dental calculus triggers nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation, leading to the processing of the interleukin-1β precursor into its mature form in mouse and human phagocytes. The activation of the NLRP3 inflammasome also induced a lytic form of programmed cell death, pyroptosis, in these cells. However, the effects of dental calculus on other cell types in periodontal tissue have not been investigated. The aim of this study was to determine whether dental calculus can induce cell death in oral epithelial cells.

MATERIAL AND METHODS

HSC-2 human oral squamous carcinoma cells, HOMK107 human primary oral epithelial cells and immortalized mouse macrophages were exposed to dental calculus or 1 of its components, hydroxyapatite crystals. For inhibition assays, the cells were exposed to dental calculus in the presence or absence of cytochalasin D (endocytosis inhibitor), z-YVAD-fmk (caspase-1 inhibitor) or glyburide (NLRP3 inflammasome inhibitor). Cytotoxicity was determined by measuring lactate dehydrogenase (LDH) release and staining with propidium iodide. Tumor necrosis factor-α production was quantified by enzyme-linked immunosorbent assay. Oral epithelial barrier function was examined by permeability assay.

RESULTS

Dental calculus induced cell death in HSC-2 cells, as judged by LDH release and propidium iodide staining. Dental calculus also induced LDH release from HOMK107 cells. Following heat treatment, dental calculus lost its capacity to induce tumor necrosis factor-α in mouse macrophages, but could induce LDH release in HSC-2 cells, indicating a major role of inorganic components in cell death. Hydroxyapatite crystals also induced cell death in both HSC-2 and HOMK107 cells, as judged by LDH release, indicating the capacity of crystal particles to induce cell death. Cell death induced by dental calculus was significantly inhibited by cytochalasin D, z-YVAD-fmk and glyburide, indicating NLRP3 inflammasome involvement. In permeability assays, dental calculus attenuated the barrier function of HSC-2 cell monolayers.

CONCLUSION

Dental calculus induces pyroptotic cell death in human oral epithelial cells and the crystalline structure plays a major role in this process. Oral epithelial cell death induced by dental calculus might be important for the etiology of periodontitis.

Clinical and mutational spectrum of Charcot-Marie-Tooth disease type 2Z caused by MORC2 variants in Japan

BACKGROUND AND PURPOSE

The microrchidia family CW-type zinc finger 2 gene (MORC2) was newly identified as a causative gene of Charcot-Marie-Tooth disease (CMT) type 2Z in 2016. We aimed to describe the clinical and mutational spectrum of patients with CMT harboring MORC2 mutations in Japan.

METHODS

We analyzed samples from 781 unrelated patients clinically diagnosed with CMT using deoxyribonucleic acid microarray or targeted resequencing by next-generation sequencing, and samples from 434 mutation-negative patients were subjected to whole-exome sequencing. We extracted MORC2 variants from these whole-exome sequencing data and classified them according to American College of Medical Genetics standards and guidelines.

RESULTS

We identified MORC2 variants in 13 patients. As the second most common causative gene of CMT type 2 after MFN2, MORC2 variants were detected in 2.7% of patients with CMT type 2. The mean age of onset was 10.3 ± 8.7 years, and the inheritance pattern was mostly sporadic (11/13 patients, 84.6%). The clinical phenotype was typically length-dependent polyneuropathy, and electrophysiological studies revealed sensory-dominant axonal neuropathy. Mental retardation was identified in 4/13 patients (30.8%). p.Arg190Trp, as a mutational hotspot, was observed in eight unrelated families. We also identified two novel probably pathogenic variants, p.Cys345Tyr and p.Ala369Val, and one novel uncertain significance variant, p.Tyr332Cys.

CONCLUSIONS

Our study is the largest report of patients harboring MORC2 variants. We revealed a clinical and mutational spectrum of Japanese patients with MORC2 variants. More attention should be paid to cognitive impairment, and the responsible mechanism requires further research for elucidation.

Tongue-palatal contact changes in patients with skeletal mandibular prognathism after sagittal split ramus osteotomy: an electropalatography study

The purpose of this study was to investigate the changes in tongue-palatal contact patterns using electropalatography (EPG) before and after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Nine clients who underwent SSRO for mandibular setback and seven control subjects were participated in this study. Tongue-palatal contact patterns for /t/, /s/ and /k/ production were investigated using EPG before surgery and 3 months after surgery. The mean value of whole total of palate contact (WT) in the maximum contact frame was examined before and after SSRO. The correlation quantity between the change of center of gravity (COG) value and the amount of mandibular setback was also evaluated. The mean value of WT for /t/ and /s/ significantly increased after SSRO, and the EPG pattern became normal. However, a remarkable change in WT for /k/ was not observed, and the mean value was significantly larger in the SSRO group before and after surgery than in the control group. A negative correlation between COG variation and the amount of mandibular setback for /t/ and positive correlation for /s/ was observed. This study demonstrated that tongue-palatal contact patterns for /t/ and /s/ articulation improved clearly after SSRO. There was a significant correlation between COG variation and the amount of mandibular setback. However, no significant change was detected through perceptual assessment before and after SSRO. Further investigation is needed to determine whether these results will change over time.

Clinical and mutational spectrum of Japanese patients with Charcot-Marie-Tooth disease caused by GDAP1 variants

BACKGROUND

Mutations in GDAP1 are responsible for heterogeneous clinical and electrophysiological phenotypes of Charcot-Marie-Tooth disease (CMT), with autosomal dominant or recessive inheritance pattern. The aim of this study is to identify the clinical and mutational spectrum of CMT patients with GDAP1 variants in Japan.

MATERIALS AND METHODS

From April 2007 to October 2014, using three state-of-art technologies, we conducted gene panel sequencing in a cohort of 1,030 patients with inherited peripheral neuropathies (IPNs), and 398 mutation-negative cases were further analyzed with whole-exome sequencing.

RESULTS

We identified GDAP1 variants from 10 patients clinically diagnosed with CMT. The most frequent recessive variant in our cohort (5/10), c.740C>T (p.A247V), was verified to be associated with a founder event. We also detected three novel likely pathogenic variants: c.928C>T (p.R310W) and c.546delA (p.E183Kfs*23) in Case 2 and c.376G>A (p.E126K) in Case 8. Nerve conduction study or sural nerve biopsy of all 10 patients indicated axonal type peripheral neuropathy.

CONCLUSION

We identified GDAP1 variants in approximately 1% of our cohort with IPNs, and established a founder mutation in half of these patients. Our study originally described the mutational spectrum and clinical features of GDAP1-related CMT patients in Japan.

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.

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.

Suppressor of cytokine signaling 1-dependent regulation of the expression and oncogenic functions of p21(CIP1/WAF1) in the liver

The SOCS1 gene coding for suppressor of cytokine signaling 1 is frequently repressed in hepatocellular carcinoma (HCC), and hence SOCS1 is considered a tumor suppressor in the liver. However, the tumor-suppressor mechanisms of SOCS1 are not yet well understood. SOCS1 is known to inhibit pro-inflammatory cytokine production and signaling and to promote activation of the p53 tumor suppressor. However, we observed that SOCS1-deficient mice developed numerous and large liver tumor nodules following treatment with the hepatocarcinogen diethylnitrosamine (DEN) without showing increased interleukin-6 production or activation of p53. On the other hand, the livers of DEN-treated Socs1-null mice showed elevated levels of p21(CIP1/WAF1) protein (p21). Even though p21 generally functions as a tumor suppressor, paradoxically many cancers, including HCC, are known to express elevated levels of p21 that correlate with poor prognosis. We observed elevated p21 expression also in the regenerating livers of SOCS1-deficient mice and in cisplatin-treated Socs1-null hepatocytes, wherein the p21 protein showed increased stability. We show that SOCS1 interacts with p21 and promotes its ubiquitination and proteasomal degradation. Besides, the DEN-treated livers of Socs1-null mice showed increased nuclear and cytosolic p21 staining, and the latter was associated with growth factor-induced, phosphatidylinositol 3-kinase-dependent phosphorylation of p21 in SOCS1-deficient hepatocytes. Cytosolic p21 is often associated with malignancy and chemo-resistance in many cancers. Accordingly, SOCS1-deficient hepatocytes showed increased resistance to apoptosis that was reversed by shRNA-mediated p21 knockdown. In the regenerating livers of Socs1-null mice, increased p21 expression coincided with elevated cyclinD levels. Correspondingly, SOCS1-deficient hepatocytes showed increased proliferation to growth factor stimulation that was reversed by p21 knockdown. Overall, our findings indicate that the tumor-suppressor functions of SOCS1 in the liver could be mediated, at least partly, via regulation of the expression, stability and subcellular distribution of p21 and its paradoxical oncogenic functions, namely, resistance to apoptosis and increased proliferation.

Regulation of MET receptor tyrosine kinase signaling by suppressor of cytokine signaling 1 in hepatocellular carcinoma

Suppressor of cytokine signaling 1 (SOCS1) is considered as a tumor suppressor protein in hepatocellular carcinoma (HCC), but the underlying mechanisms remain unclear. Previously, we have shown that SOCS1-deficient hepatocytes displayed increased responsiveness to hepatocyte growth factor (HGF) due to enhanced signaling via the MET receptor tyrosine kinase. As aberrant MET activation occurs in many tumors including HCC, here we elucidated the mechanisms of SOCS1-mediated regulation. SOCS1 attenuated HGF-induced proliferation of human and mouse HCC cell lines and their growth as tumors in NOD.scid.gamma mice. Tumors formed by SOCS1 expressing HCC cells showed significantly reduced MET expression, indicating that SOCS1 not only attenuates MET signaling but also regulates MET expression. Mechanistically, SOCS1 interacted with MET via the Src homology 2 domain and this interaction was promoted by MET tyrosine kinase activity. The SOCS1-mediated reduction in MET expression does not require the juxtamembrane Y1003 residue implicated in Cbl-mediated downmodulation. Moreover, the proteasome inhibitor MG-132, but not the inhibitors of lysosomal degradation bafilomycin and chloroquine, reversed the SOCS1-mediated reduction in MET expression, indicating that this process is distinct from Cbl-mediated downmodulation. Accordingly, SOCS1 promoted polyubiquitination of MET via K48-dependent but not K63-mediated ubiquitin chain elongation. Furthermore, siRNA-mediated downmodulation of Cbl did not abolish SOCS1-mediated reduction in MET expression in HCC cells. SOCS1-dependent ubiquitination of endogenous MET receptor occurred rapidly following HGF stimulation in HCC cells, leading to proteasomal degradation of phosphorylated MET receptor. These findings indicate that SOCS1 mediates its tumor suppressor functions, at least partly, by binding to MET and interfering with downstream signaling pathways as well as by promoting the turnover of the activated MET receptor. We propose that loss of this control mechanism due to epigenetic repression of SOCS1 could contribute to oncogenic MET signaling in HCC and other cancers, and that MET inhibitors might be useful in treating these patients.