Hyperacute postprocedural high platelet reactivity: a novel predictor for in-hospital adverse events in acute coronary syndrome with prasugrel loading

Introduction

Postprocedural High platelet reactivity (HPR) seems to associate long term adverse cardiovascular events, mainly intrastent thrombosis. However, the relationship between hyper-acute postprocedural HPR with prasugrel loading and clinical outcomes in acute coronary syndrome (ACS) is still unclear. Moreover, factors contributing HPR in ACS with prasugrel loading are also unknown.

Purpose

This study aimed to assess the impact of hyper-acute postprocedural HPR with prasugrel loading on clinical outcomes in ACS during hospitalization, as well as to define appropriate cut-off values and identify contributing factors of HPR.

Methods

We performed a single-centre, retrospective observational study that enrolled 207 patients who underwent emergent PCI for ACS with prasugrel loading. The P2Y12reaction unit (PRU) value was measured immediately after PCI with the VerifyNow System. The primary endpoint was major adverse cardiac events (MACE, defined as the composite of death, myocardial infarction, stroke, heart failure, ventricular arrhythmia needing defibrillation).

Results

Mean patient age (standard deviation) was 70.5 (±13.0) years, 78.7% were male, and average time from prasugrel intake to PRU calculation was 98.3 (±49.1) min. During a mean hospital stay of 15.9 (±9.3) days, there were 34 in-hospital MACE (16.4%) and 10 deaths (4.8%). Thrombosis events, didn't stand out and mechanical complications, such as cardiac rupture and cardiac tamponade occupies most of cardiovascular death which occurred before 10 days on admission. PRU was significantly higher in MACE group than Non-MACE group (279±65 vs 227±72, p<0.001 respectively). The ROC curve analysis of PRU for discriminating significant in-hospital MACE showed the cut off value of 293 (sensitivity:52.9%, specificity:83.2% [AUC=0.709, p<0.0001]). 47patients (29.4%) were thus categorized as HPR (PRU>293) immediately after emergent PCI. Kaplan-Meyer curve showed MACE events occurred in HPR group than non-HPR group (38.2% vs 10.0%, p<0.001). Multiple cox analysis demonstrated that HPR was independent predictors of MACE in patients with ACS underwent PCI (OR 5.416, 95% CI 2.157–13.598, p<0.0001). Multiple logistic regression model showed female sex, low haemoglobin value, and large mean platelet volume were independent predictors of HPR.

Conclusion

PRU was significantly higher in MACE group, and appropriate cut-off value of HPR in this study was 293. HPR was independent predictor of MACE during hospitalization, however thrombosis event was not significant. Evidence of clinical impact with postprocedural HPR within 120 minutes after prasugrel loading is scarce. This study shows post-procedural HPR, even without sufficient time after prasugrel intake, can be a useful predictive marker of adverse events during hospitalization.

Funding Acknowledgement

Type of funding sources: None. PRU between Non-MACE and MACE groupKaplan-Meyer curve

Cardio-ankle vascular index is useful screening method to detect obstructive coronary artery disease in asymptomatic diabetes patients with subclinical atherosclerosis

Background

Patients with diabetes mellitus are at very high risk for obstructive coronary artery disease; however, invasive coronary angiography is not allowed to apply in all patients. Cardio-ankle vascular index (CAVI), a marker of arterial stiffness has been reported to reflect atherosclerotic burden.

Purpose

To assess the diagnostic performance of CAVI vs. coronary calcium score for detecting obstructive coronary artery disease determined by Coronary CT angiography (CCTA) in asymptomatic diabetes patients.

Methods

During May 2015 to December 2019, 816 patients with diabetes mellitus were evaluated. First, intima-media thickness of carotid artery was measured in all subjects. Then, patients with intima-media thickness over 11mm underwent CAVI. Finally, 209 patients who have one or more cardiovascular risk factors other than diabetes mellitus were enrolled (68±11 years, 68% men). Patients were excluded if they had a disorder of the kidney, a prior history of coronary artery revascularization, atrial fibrillation, LV ejection fraction <50%, ABI <0.9 or allergy to contrast. Diagnostic performance of CAVI was evaluated with coronary stenosis >50% by CCTA.

Results

CAVI, Agatston score, and intima-media thickness of carotid artery were 9.2±1.3, 396±621 and 2.0±0.7mm, respectively. CAVI was significantly correlated with age (r=0.530, p<0.001), coronary artery calcification (r=0.182, p=0.008), and intima-media thickness of carotid artery (r=0.195, p=0.005). Among them, 108 patients (48%) had coronary stenosis. CAVI, Agatston score and intima-media thickness of carotid artery in patients with coronary stenosis were higher than that without coronary stenosis, respectively (9.8±1.1 vs 8.5±1.0, p<0.001, 526±676 vs. 255±525, p=0.001, 2.2±0.7 vs. 1.8±0.6, p<0.001). The ROC curve analysis of CAVI for discriminating coronary stenosis showed that the sensitivity 75.0% and specificity 77.2% at the cut off value of 9.23 (AUC=0.812, p<0.001). Contrastingly, diagnostic performance of coronary calcium score and intima-media thickness of carotid artery were less than CAVI (sensitivity: 91.7%, specificity: 56.4%, AUC=0.753, p<0.05 vs. CAVI, sensitivity: 68.5%, specificity: 59.4%, AUC=0.663, p<0.05 vs. CAVI). Multivariate logistic analysis demonstrated that CAVI was significantly associated with coronary stenosis (OR=4.133, p<0.001) after adjustment of conventional risk factors, although coronary calcium score was not correlated with coronary stenosis.

Conclusion

CAVI could be informative to select patients having obstructive coronary artery disease in asymptomatic diabetes patients with thick intima-media thickness.

Funding Acknowledgement

Type of funding sources: None.

Impact of high platelet reactivity on left ventricular remodeling in patients with acute coronary syndrome

Background/Introduction

Previous studies demonstrated that high platelet reactivity (HPR) predicts future cardiovascular death and coronary events in patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). However, few studies have focused on the impact of HPR on left ventricular remodeling (LVR) and each echocardiographic parameter.

Purpose

The purpose of this study was to investigate the impact of HPR in ACS patients on LVR and changes in echocardiographic volume indexes and LV ejection fraction.

Methods

This is a retrospective cohort study of prospectively collected data in a single center that enrolled patients who underwent emergency PCI for ACS including STEMI and NSTEMI with prasugrel loading. The primary outcome of the study was LVR associated with HPR. Secondary endpoints were changes in indexed LVESV, LVEDV, LVEF, E/e' and LAVI between baseline and follow-up. The P2Y12 reaction unit (PRU) value in response to prasugrel was assessed by the VerifyNow P2Y12 assay. Blood samples were collected once per procedure immediately after PCI. LVR index was calculated as the relative change in LVEDV observed at follow-up compared with baseline. LVR was defined as a relative increase in LVEDV ≥20%, measured at follow-up visit compared with the baseline value before discharge.

Results

A total of 196 ACS patients who underwent emergency PCI between January 2016 and July 2020 were enrolled in the study. The mean age of the study population was 69.9 years, and 76.0% were male. On echocardiography at follow up visit of mean duration of 7.0±4.0 months, LVR was found in 38 patients (19.4%). The optimal cutoff for PRU associated with increased LVR assessed by receiver-operating characteristic curve analysis was 245.5 (AUC: 0.656; 95% CI: 0.564 to 0.749; p=0.003). On the basis of this cutoff, HPR was found in 82 patients (42.1%) and the prevalence of LVR was significantly higher in the HPR group compared to the non-HPR group (30.5% vs. 11.4%; p=0.001). Multiple Cox regression analysis showed that HPR was an independent predictor of LVR (OR 4.22, 95% CI 1.83–9.71, p=0.001). In addition, Δ% EDV and Δ% ESV increased in the HPR group, and decreased in the non-HPR group with significant differences (5.8±32.6% vs. −8.0±26.2% in Δ% EDV; p=0.002, 2.0±37.5% vs. −13.3±33.0% in Δ% ESV; p=0.004, respectively). Δ%EF, Δ%E/e', Δ%LAVI were numerically improved in the non-HPR group compared with the HPR group, but this difference did not reach statistical significance.

Conclusion

In patients with ACS, HPR defined as PRU ≥246 immediately after emergency PCI was an independent predictor of LVR in the chronic phase.

Funding Acknowledgement

Type of funding sources: None. Predictors of the presence of LVRChanges (Δ%) of LVEDV and LVESV

Computational Fluid Dynamics Using a Porous Media Setting Predicts Outcome after Flow-Diverter Treatment

BACKGROUND AND PURPOSE

Knowledge about predictors of the outcome of flow-diverter treatment is limited. The aim of this study was to predict the angiographic occlusion status after flow-diverter treatment with computational fluid dynamics using porous media modeling for decision-making in the treatment of large wide-neck aneurysms.

MATERIALS AND METHODS

A total of 27 patients treated with flow-diverter stents were retrospectively analyzed through computational fluid dynamics using pretreatment patient-specific 3D rotational angiography. These patients were classified into no-filling and contrast-filling groups based on the O'Kelly-Marotta scale. The patient characteristics, morphologic variables, and hemodynamic parameters were evaluated for understanding the outcomes of the flow-diverter treatment.

RESULTS

The patient characteristics and morphologic variables were similar between the 2 groups. Flow velocity, wall shear stress, shear rate, modified aneurysmal inflow rate coefficient, and residual flow volume were significantly lower in the no-filling group. A novel parameter, called the normalized residual flow volume, was developed and defined as the residual flow volume normalized by the dome volume. The receiver operating characteristic curve analyses demonstrated that the normalized residual flow volume with an average flow velocity of ≥8.0 cm/s in the aneurysmal dome was the most effective in predicting the flow-diverter treatment outcomes.

CONCLUSIONS

It was established in this study that the hemodynamic parameters could predict the angiographic occlusion status after flow-diverter treatment.

Intracranial Subdural Hematoma after Lumbar Spine Surgery: A Case Report

Intracranial subdural hematoma following lumbar surgery is a devastating but rare complication. It has been implicated due to intracranial hypotension secondary to persistent cerebrospinal fluid leakage. The resultant drop in intracranial pressure presumably causes traction and tearing of venous structures. Patients typically present with postural headaches. However, other symptoms of subdural hematoma, intracranial hypotension and cerebrospinal fluid leak must also be cautioned.

P4678The hemodynamic improvement with balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension depends on the lesion location

Background

Pulmonary endarterectomy (PEA) is a treatment of choice for patients with chronic thromboembolic pulmonary hypertension (CTEPH). Patients with proximal pulmonary artery disease are considered to be good candidates for PEA because of their generally excellent outcomes. However, not all patients can be operated because of patients' advanced age, comorbidities and poor general condition. Balloon pulmonary angioplasty (BPA) has become an alternative treatment for CTEPH patients especially whose lesions locate in the distal site. The effectiveness of BPA in patients who have lesions in the proximal pulmonary arteries but cannot be a candidate for PEA remains unclear.

Purpose

The aim of this study was to investigate the outcome of BPA in CTEPH patients whose lesions appears operable but ineligible for PEA.

Methods

A total of 370 patients who underwent BPA in our institute from November 2004 to January 2018 were enrolled. All the patients were divided into operable group and inoperable group according to the difference of lesion location based on the findings of perfusion scintigraphy, computed tomography and pulmonary angiography. Hemodynamic effects of BPA in both groups were investigated. We also conducted survival analyses using the Kaplan-Meier method with the log-rank test.

Results

Among 370 patients, 90 patients deemed operable. The main reasons why not operated in the PEA operable group were patient's refusal (44%), advanced age (14%), and comorbidities (27%). There were no baseline characteristic differences between two groups except for the history of acute pulmonary embolism. Mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) equally improved after BPA in both groups (operable: 38.2±10.8 mmHg to 21.5±4.7mmHg, inoperable: 42.4±11.3 mmHg to 21.8±4.8 mmHg, p<0.001, operable: 8.0±4.2 wood unit to 3.5±1.5 wood unit, inoperable: 9.1±4.6 wood unit to 3.4±1.3 wood unit, p<0.001). Furthermore, five-year cumulative survival rates were not different between two groups (inoperable vs. operable: 93% vs. 88%, p=0.23, median follow-up period was 23.0 months (range: 5–136 months)). Meanwhile, the absolute change of mPAP and PVR in inoperable group were greater than those in operable group (inoperable: 20.7±11.2 mmHg, operable: 16.6±11.0 mmHg, p=0.010, inoperable: 5.6±4.4 wood unit, operable: 4.5±3.9 wood unit, p=0.015).

Conclusions

Although the outcome of BPA for CTEPH patients with operable lesions appears acceptable, absolute change in hemodynamics was lower than that of the patients with inoperable lesions. CTEPH with proximal lesions should be treated with PEA rather than BPA.

P4675The utility of additional balloon pulmonary angioplasty for residual hypoxemia in normohemodynamic chronic thromboembolic pulmonary hypertension patients after invasive treatments

Background

Balloon pulmonary angioplasty (BPA) improves hemodynamics, symptoms and exercise capacity in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are ineligible for pulmonary endarterectomy (PEA). However, certain patients still have hypoxemia after BPA or PEA despite normalization of hemodynamics. In CTEPH, hypoxemia is related increased dead space ventilation caused by vascular obstruction.

Purpose

This study was aimed to clarify whether additional BPA can improve hypoxemia of CTEPH patients after normalization of hemodynamics.

Methods

A total of 335 patients who underwent initial series of BPA in our institute were followed up. Sixty-four patients with mean pulmonary artery pressure (mPAP) <30mmHg and percutaneous oxygen saturation (SpO2) <95% without oxygen inhalation at more than 6 months after the initial series of BPA and of patients who could reevaluate hemodynamics and oxygenation after additional BPA were enrolled. These patients were divided into two groups with or without additional BPA procedures. Change of hemodynamics and SpO2 were retrospectively investigated.

Results

Thirty-three of 64 patients underwent additional BPA procedures. Patients' age was older in BPA group than those in non-BPA group (71.3±10.4 vs. 66.5±9.4 years old, p=0.02). mPAP and pulmonary vascular resistance (PVR) was significantly higher in BPA group (mPAP: 23.9±3.2 vs. 20.7±3.8 mmHg, p=0.001, PVR: 4.2±1.2 vs. 3.5±1.4 wood unit, p=0.03, respectively). Among the 1.8±1.4 BPA procedures per person, total 6.6±3.8 segmental pulmonary arteries per person were treated. While no obvious improvements were observed in non-BPA group, PVR and SpO2 in BPA group were significantly improved (4.2±1.2 to 3.7±1.3 wood unit, p=0.002, 90.7±3.1% to 94.1±3.6%, p<0.001, respectively). In the multivariate logistic regression analysis, additional BPA procedures were associated with further improvement of SpO2 (hazard ratio, 3.7; 95% confidence interval, 1.2–11.5; P=0.02).

Conclusions

Additional BPA procedure was associated with improvement of hypoxemia in CTEPH patients after normalization of hemodynamics. Treating as many lesions as possible in BPA might relieve the patients' residual dyspnea.

The number of microvascular complications is associated with an increased risk for severity of periodontitis in type 2 diabetes patients: Results of a multicenter hospital-based cross-sectional study

Aims/Introduction

To explore the relationships between periodontitis and microvascular complications as well as glycemic control in type 2 diabetes patients.

Materials and Methods

This multicenter, hospital‐based, cross‐sectional study included 620 patients with type 2 diabetes. We compared the prevalence and severity of periodontitis between patients with ≥1 microvascular complication and those without microvascular complications. We also compared the prevalence and severity of periodontitis among patients with different degrees of glycemic control.

Results

After adjusting for confounding factors, multiple logistic regression analysis showed that the severity of periodontitis was significantly associated with the number of microvascular complications (odds ratio 1.3, 95% confidence interval 1.1–1.6), glycated hemoglobin ≥8.0% (64 mmol/mol; odds ratio 1.6; 95% confidence interval 1.1–2.3), and older age (≥50 years; odds ratio 1.7; 95% confidence interval 1.1–2.6). However, the prevalence of periodontitis was not significantly associated with the number of microvascular complications, but was associated with male sex, high glycated hemoglobin (≥8.0% [64 mmol/mol]), older age (≥40 years), longer duration of diabetes (≥15 years) and fewer teeth (≤25). Furthermore, propensity score matching for age, sex, diabetes duration and glycated hemoglobin showed that the incidence of severe periodontitis was significantly higher among patients with microvascular complications than among those without microvascular complications (P < 0.05).

Conclusions

The number of microvascular complications is a risk factor for more severe periodontitis in patients with type 2 diabetes, whereas poor glycemic control is a risk factor for increased prevalence and severity of periodontitis.

Chloride ion transport and overexpression of TMEM16A in a guinea-pig asthma model

BACKGROUND

TMEM16A, a Ca-activated Cl channel, regulates various physiological functions such as mucin secretion. However, the role of TMEM16A in hyper-secretion in asthma is not fully understood.

OBJECTIVE

The aim of this study is to evaluate Cl ion transport via TMEM16A and determine the localization of TMEM16A in a guinea-pig asthma model.

METHODS

Guinea-pigs were sensitized with ovalbumin (OVA) i.p. on Days 1 and 8. On Day 22, we assessed OVA challenge-induced Cl ion transport in the sensitized tracheas ex vivo in an Ussing chamber, compared with the non-sensitized tracheas. We then examined the effect of T16Ainh-A01, a TMEM16A inhibitor, on the increase in Cl ion transport. The tracheal epithelium was immunostained with an anti-TMEM16A antibody. Epithelial cells from guinea-pig tracheas were cultured at the air-liquid interface in the presence of IL-13 for in vitro study. We studied the effect of TMEM16A inhibitors on Ca-dependent agonist, uridine triphosphate (UTP)-induced increases in Cl ion transport in the cultured cells. The cells were immunostained with an anti-TMEM16A antibody, an anti-MUC5AC antibody and an anti-α-tubulin antibody.

RESULTS

OVA challenge induced an increase in short circuit current within 1 min in the OVA-sensitized tracheas but not in the non-sensitized tracheas, which was inhibited by pretreatment of T16Ainh-A01. Sensitized tracheas showed goblet cell metaplasia with more positive TMEM16A immunostaining, particularly in the apical portion compared with the non-sensitized tracheas. The in vitro UTP-induced increase in Cl ion transport was strongly inhibited by pretreatment with T16Ainh-A01, benzbromarone, and niflumic acid. TMEM16A was positively immunostained at the apical portion and in the MUC5AC-positive area in IL-13-induced goblet cell metaplasia.

CONCLUSIONS

Antigen challenge and Ca-dependent agonist treatment increased Cl ion transport via the overexpression of TMEM16A in goblet cell metaplasia in a guinea-pig asthma model. TMEM16A inhibitors may be useful for the treatment of hyper-secretion in asthma.

Abstract P4-02-04: Using ultrasound findings to predict high tumor-infiltrating lymphocytes in triple negative breast cancer

Purpose Previous clinical data showed that high tumor-infiltrating lymphocytes (TILs) indicated a good prognosis in triple negative breast cancer (TNBC) and suggested that TNBC with TILs responded well to immunotherapy. Breast ultrasound is a safe inspection method without any radiation exposure. Therefore, we investigated whether ultrasound findings can predict high TILs in TNBC.

Patients and Methods The TNBC patients who underwent surgery at Mitsui Memorial Hospital, Tokyo, Japan, from 2009 to 2015, including those who underwent neo adjuvant chemotherapy (NAC), were selected for this study. The pre-treatment ultrasound findings were used retrospectively, and we compared the shape, margin, homogeneity of internal echoes, posterior features, and growth pattern of the lesions. Regarding shape, we classified the ultrasound findings as “round”, “oval”, “lobulated”, “irregular”, and “other” in accordance with The Japan Associations of Breast and Thyroid Sonology. Similarly, we classified the margins as "circumscribed" or "well-defined and smooth", "well-defined and rough", "indistinct" and "obscure". We used “homogeneous” and “heterogeneous” internal echoes. In terms of posterior features, we used the “accentuation”, “not changing”, “attenuating” and “shadowing” categories. By referring to previous report, we classified four types of growth patterns, i.e., "growing along the mammary ducts", "expansive growth pattern", "irregularly shaped mass with retracting surrounding tissue" and "other". Two pathologists evaluated stromal TILs, which were located between the cancer nests, by surgical specimens or needle biopsies of those who underwent NAC. Then the TILs were classified into four groups: “absent”, “weak”, “moderate”, and “dense”. “Absent” indicated that there were no lymphocytes in the stroma. “Weak”, “moderate” and “dense” indicated that lymphocytes occupied about 1–40%, 40–75% and 75%–100% area in the stroma, respectively. We analyzed ultrasound findings and TILs with the χ -square test.

Results A total of 97 lesions and 95 female TNBC patients were validated. The median age was 62 years old (range, 32–88 years). Of the total, 37 patients underwent NAC. The degree of “absent” TILs was 5 lesions, “weak” was 58, “moderate” was 22, and “dense” was 12 lesions. In the ultrasound findings, the shape categories “round,” “oval,” and “lobulated” were more "dense" TILs (n=12, 100%) than others (n=47, 55.3%) (p = 0.002). The "circumscribed" and "well-defined and rough" margins were found to be more “dense” TILs (n=11, 91.7%) than the other TILs (n=49, 57.6%) (p=0.020). “Accentuating” posterior echoes were more “dense” and “moderate” TILs (n=23, 67.6%) than “weak” and “absent” TILs (n=25, 39.7%) (p=0.009). The lesions with expansively growing pattern showed higher rate “dense” and “moderate” TILs (n=20, 58.8%) than “weak” and “absent” TILs (n=20, 31.7%) (p=0.010). There were no significant differences in internal echoes.

Conclusion We determined that ultrasound findings of round, oval or lobulated shape, accentuating posterior echoes and expansively growing pattern could predict the presence of high TILs. Thus, the safe, low-cost, and radiation-free ultrasound examination was recommended for predicting high TILs and prognosis.

Citation Format: Inagaki M, Ota D, Tsuji M, Kobayashi Y, Mori M, Fukuuchi A. Using ultrasound findings to predict high tumor-infiltrating lymphocytes in triple negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-02-04.

Long-Term Persistence of Donor Alveolar Macrophages in Human Lung Transplant Recipients That Influences Donor-Specific Immune Responses

Steady-state alveolar macrophages (AMs) are long-lived lung-resident macrophages with sentinel function. Evidence suggests that AM precursors originate during embryogenesis and populate lungs without replenishment by circulating leukocytes. However, their presence and persistence are unclear following human lung transplantation (LTx). Our goal was to examine donor AM longevity and evaluate whether AMs of recipient origin seed the transplanted lungs. Origin of AMs was accessed using donor-recipient HLA mismatches. We demonstrate that 94-100% of AMs present in bronchoalveolar lavage (BAL) were donor derived and, importantly, AMs of recipient origin were not detected. Further, analysis of BAL cells up to 3.5 years post-LTx revealed that the majority of AMs (>87%) was donor derived. Elicitation of de novo donor-specific antibody (DSA) is a major post-LTx complication and a risk factor for development of chronic rejection. The donor AMs responded to anti-HLA framework antibody (Ab) with secretion of inflammatory cytokines. Further, in an experimental murine model, we demonstrate that adoptive transfer of allogeneic AMs stimulated humoral and cellular immune responses to alloantigen and lung-associated self-antigens and led to bronchiolar obstruction. Therefore, donor-derived AMs play an essential role in the DSA-induced inflammatory cascade leading to obliterative airway disease of the transplanted lungs.

Automatic generation of smart earthquake-resistant building system: Hybrid system of base-isolation and building-connection

A base-isolated building may sometimes exhibit an undesirable large response to a long-duration, long-period earthquake ground motion and a connected building system without base-isolation may show a large response to a near-fault (rather high-frequency) earthquake ground motion. To overcome both deficiencies, a new hybrid control system of base-isolation and building-connection is proposed and investigated. In this new hybrid building system, a base-isolated building is connected to a stiffer free wall with oil dampers. It has been demonstrated in a preliminary research that the proposed hybrid system is effective both for near-fault (rather high-frequency) and long-duration, long-period earthquake ground motions and has sufficient redundancy and robustness for a broad range of earthquake ground motions.An automatic generation algorithm of this kind of smart structures of base-isolation and building-connection hybrid systems is presented in this paper. It is shown that, while the proposed algorithm does not work well in a building without the connecting-damper system, it works well in the proposed smart hybrid system with the connecting damper system.

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.