Regulation of von Willebrand factor by ADAMTS13 ameliorates lipopolysaccharide-induced lung injury in mice

The relationship between von Willebrand factor (VWF) and inflammation has attracted considerable attention in recent years. VWF, which is stored in the Weibel-Palade bodies (WPBs) of endothelial cells (ECs), is released from WPBs in response to inflammatory stimuli and is thought to contribute to inflammation by promoting leukocyte extravasation. In this study, lung injury model mice were produced by intratracheal injection with lipopolysaccharides. The severity of lung inflammation was evaluated in mice with different genotypes (wild-type, Vwf-/-, Adamts13-/-) and mice treated with drugs that inhibit VWF function. Lung inflammation was significantly ameliorated in Vwf-/- mice compared with wild-type mice. Furthermore, inflammation was significantly suppressed in wild-type mice treated with anti-VWF A1 antibody or recombinant human ADAMTS13 compared with the untreated control group. The underlying mechanism appears to be an increased VWF/ADAMTS13 ratio at the site of inflammation and the interaction between blood cell components, such as leukocytes and platelets, and the VWF A1 domain, which promotes leukocyte infiltration into the lung. This study suggested that ADAMTS13 protein and other VWF-targeting agents may be a novel therapeutic option for treatment of pulmonary inflammatory diseases.

Platelet Receptor Glycoprotein VI-Dimer Is Overexpressed in Patients with Atrial Fibrillation at High Risk of Ischemic Stroke

Introduction  Atrial fibrillation (AF) increases the risk of ischemic stroke (IS). We hypothesized that the functional form of platelet receptor glycoprotein (GP) VI, GPVI-dimer, which binds to collagen and fibrin causing platelet activation, is overexpressed in patients with AF who have not had a stroke. Methods  A total of 75 inpatients with AF were recruited. None were admitted with or had previously had thrombotic events, including IS or myocardial infarction. Platelet surface expression of total GPVI, GPVI-dimer, and the platelet activation marker P-selectin were quantitated by whole blood flow cytometry. Serum biomarkers were collected in AF patients. Results were compared against patients contemporaneously admitted to hospital with similar age and vascular risk-factor profiles without AF (noAF, n  = 30). Results  Patients with AF have similar total GPVI surface expression ( p  = 0.58) and P-selectin exposure ( p  = 0.73) on their platelets compared with noAF patients but demonstrate significantly higher GPVI-dimer expression ( p  = 0.02 ). Patients with paroxysmal AF express similar GPVI-dimer levels compared with permanent AF and GPVI-dimer levels were not different between anticoagulated groups. Serum N-terminal pro b-type natriuretic peptide ( p  < 0.0001 ) and high sensitivity C-reactive protein ( p  < 0.0001 ) were significantly correlated with GPVI-dimer expression in AF platelets. AF was the only vascular risk factor that was independently associated with higher GPVI-dimer expression in the whole population ( p  = 0.02 ) . Conclusion  GPVI inhibition is being explored in clinical trials as a novel target for IS treatment. As GPVI-dimer is elevated in AF patients' platelets, the exploration of targeted GPVI-dimer inhibition for stroke prevention in patients at high risk of IS due to AF is supported.

Prevalence and implications of exercise pulmonary hypertension in chronic thromboembolic pulmonary disease

Introduction

Recent international statement on chronic thromboembolic pulmonary hypertension proposed the definition of chronic thromboembolic pulmonary disease (CTEPD) and advocated further research regarding its clinical characteristic, natural history, and therapeutic strategy. Exercise pulmonary hypertension (Ex-PH) has been considered a mild degree of pulmonary hypertension (PH) among patients with normal pulmonary hemodynamics at rest. However, the clinical significance of Ex-PH in CTEPD remains unknown.

Purpose

In the patients with CTEPD, we aimed to verify 1) the prevalence and clinical profiles of Ex-PH, 2) effect of BPA on pulmonary vascular response after exercise in Ex-PH, 3) long-term clinical outcomes of conservative management in non-Ex-PH.

Methods

We retrospectively reviewed 26 patients with CTEPD (median age 65 years, 38% male), who underwent cardiopulmonary exercise test with right heart catheterization (CPET-RHC). The definitions of CTEPD are the following 1) pulmonary artery occlusion due to organic thrombus confirmed by imaging studies after ≥3 months of anticoagulation, 2) mPAP&lt;25 mmHg and PAWP≤15 mmHg at rest. PQslope was plotted using multipoint plots. Ex-PH was defined by PQ slope&gt;3.0, and the patients were divided into Ex-PH and non-Ex PH groups. Clinical profiles and long-term outcomes were compared between two groups. The patients in Ex-PH groupunderwent CPET-RHC 6–12 months after balloon pulmonary angioplasty (BPA). In Non-Ex-PH group, serial measurements of echocardiography were performed.

Results

Overall, 5 and 21 patients were categorized as CTEPD with PH (mPAP 21–24mmHg) and without PH (mPAP≤20mmHg), and 14 and 12 were categorized Ex-PH and non-Ex-PH groups, respectively. Although all 5 patients with CTEPD with PH were classified as Ex-PH group (Figure 1), there was no significant difference in baseline hemodynamics at rest between Ex-PH and non-Ex-PH groups (mPAP: 19.5 [18.4–20.6] vs. 17.7 [16.6–18.9] mmHg, PVR: 2.2 [1.7–2.7] vs. 2.3 [1.9–2.8] wood units, P&gt;0.05, respectively). PQ slope was significantly higher in Ex-PH group (4.6 [3.2–6.0] vs. 1.31 [0.2–2.8], p=0.002). There were no differences in respiratory function test, blood gas analysis, and 6-minute walk distance between two groups. There were no major adverse events such as all-cause mortality and hospitalization for PH in overall cohort. Among Ex-PH group, BPA decreased PQslope (4.8 [3.6–6.4] to 2.3 [1.9–3.0], p&lt;0.05). Among no-Ex-PH group, there was no significant change in tricuspid regurgitation pressure gradient (28 [17–33] to 27 [21–36] mmHg, p&gt;0.05) over the 997 [651–1451] days.

Conclusion

Ex-PH was common in patients with CTEPD, and there were no clinical profiles differentiating Ex-PH from non-Ex-PH, except parameters of CPET-RHC. BPA improved an abnormal pulmonary vascular response to exercise in Ex-PH. The conservative management in non-Ex-PH was feasible. Randomized clinical trials will be needed to further investigate this treatment strategy.

Funding Acknowledgement

Type of funding sources: None.

The outcome spectrum for Dilated Cardiomyopathy and Ventricular Tachycardia: results from the prospective, multicenter, DCM-VT ablation study

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): The study was partially supported by an investigator initiated grant from Biosense Webster (a Johnson & Johnson company)

Background

Recurrent sustained ventricular tachycardia (VT) due to nonischemic dilated cardiomyopathy (DCM) is difficult to treat and long-term outcome data are limited.

Objective

We aimed to identify predictors for mortality or heart transplantation (MHT) and VT recurrence.

Methods

Consecutive DCM patients accepted for VT catheter ablation (RFCA) in 9 centers were prospectively enrolled and followed.

Results

Of 281 consecutive patients (age 60±13yrs, 85% men, LVEF 36±12%) 35% had VT storm, 20% incessant VT, and 68% failed amiodarone. During a median follow-up of 21 (IQR 6-30) months after RFCA (epicardial in 58%, no RFCA due to inaccessible target in 6.4%), 67(24%) patients died/underwent HT and 138(49%) had VT recurrence (45 within 30 days defined as early); the cumulative 4-year rate of VT or MHT was 70% and of MHT 38%.

In multivariable analysis predictors of MHT were early VT recurrence (HR 2.92 (CI1.37-6.21), p&lt;0.01), amiodarone at discharge (HR 3.23 (CI1.43-7.33, p&lt;0.01), renal dysfunction (HR 1.92 (CI1.01-3.64), p=0.046), and LVEF (HR 1.36 (CI 1.0-1.84), p=0.052). A LVEF ≤32% was the optimal threshold to identify patients at risk for MHT (AUC 0.75).

MHT per 100 person-years was 40.4 after early VT recurrence and significantly higher, compared to 14.2 after later VT recurrence and to 8.5 after RFCA with no VT recurrence (both p&lt;0.01). Mortality rates for patients with VT recurrence after 30 days were not significantly higher than for patients with no VT recurrences

Patients with early recurrence and LVEF≤32% had a 1-year MHT rate of 55% (figure). VT recurrence was predicted by prior ICD shocks, basal antero-septal VT origin, and procedural failure but not LVEF.

Conclusion

DCM patients needing RFCA for VT are a high-risk group. Following RFCA half remain free of VT recurrences. Early VT recurrence with LVEF&lt;0.32 identifies those with a very high risk and screening for mechanical support/ HT should be considered. Late VT recurrence after RFCA does not predict worse outcome.

Platelet surface receptor glycoprotein VI-dimer is overexpressed in stroke: The Glycoprotein VI in Stroke (GYPSIE) study results

Objectives

Platelet activation underpins thrombus formation in ischemic stroke. The active, dimeric form of platelet receptor glycoprotein (GP) VI plays key roles by binding platelet ligands collagen and fibrin, leading to platelet activation. We investigated whether patients presenting with stroke expressed more GPVI on their platelet surface and had more active circulating platelets as measured by platelet P-selectin exposure.

Methods

129 ischemic or hemorrhagic stroke patients were recruited within 8h of symptom onset. Whole blood was analyzed for platelet-surface expression of total GPVI, GPVI-dimer, and P-selectin by flow cytometry at admission and day-90 post-stroke. Results were compared against a healthy control population (n = 301).

Results

The platelets of stroke patients expressed significantly higher total GPVI and GPVI-dimer (P<0.0001) as well as demonstrating higher resting P-selectin exposure (P<0.0001), a measure of platelet activity, compared to the control group, suggesting increased circulating platelet activation. GPVI-dimer expression was strongly correlated circulating platelet activation [r² = 0.88, P<0.0001] in stroke patients. Furthermore, higher platelet surface GPVI expression was associated with increased stroke severity at admission. At day-90 post-stroke, GPVI-dimer expression and was further raised compared to the level at admission (P<0.0001) despite anti-thrombotic therapy. All ischemic stroke subtypes and hemorrhagic strokes expressed significantly higher GPVI-dimer compared to controls (P<0.0001).

Conclusions

Stroke patients express more GPVI-dimer on their platelet surface at presentation, lasting at least until day-90 post-stroke. Small molecule GPVI-dimer inhibitors are currently in development and the results of this study validate that GPVI-dimer as an anti-thrombotic target in ischemic stroke.

A novel monoclonal antibody cross-reactive with both human and mouse α9 integrin useful for therapy against rheumatoid arthritis

This study introduces a novel monoclonal anti-α9 integrin antibody (MA9-413) with human variable regions, isolated by phage display technology. MA9-413 specifically binds to both human and mouse α9 integrin by recognizing a conserved loop region designated as L1 (amino acids 104-122 of human α9 integrin). MA9-413 inhibits human and mouse α9 integrin-dependent cell adhesion to ligands and suppresses synovial inflammation and osteoclast activation in a mouse model of arthritis. This is the first monoclonal anti-α9 integrin antibody that can react with and functionally inhibit both human and mouse α9 integrin. MA9-413 allows data acquisition both in animal and human pharmacological studies without resorting to surrogate antibodies. Since MA9-413 showed certain therapeutic effects in the mouse arthritis model, it can be considered as a useful therapy against rheumatoid arthritis and other α9 integrin-associated diseases.

Leg raise can detect exercise-induced pulmonary arterial wedge pressure elevation

Background

Exercise-induced elevation of pulmonary arterial wedge pressure (PAWP) may show preclinical or exercise-induced left ventricular diastolic dysfunction. Invasive hemodynamic assessment during provocative maneuvers, like exercise and volume challenge, in these patients allows greater sensitivity to diagnose or exclude HFpEF. The aim of this study was to examine how the leg raise, which is a simple way to increase preload, can detect exercise-induced PAWP elevation.

Methods

Four hundred seventy-nine patients (60±14y.o, mean pulmonary arterial pressure (PAP) 19mmHg, PAWP 8mmHg, CTEPH /IPAH/CTD-PH/SOB unknown reason: 357/56/38/28pts) with near-normal PAP and normal PAWP at rest underwent symptom-limited exercise test using supine cycle ergometer with right heart catheter. Exercise-induced elevation in PAWP of over 20mmHg was defined as exercise-induced elevation group.

Results

ΔPAWP (after leg raise - rest) in the exercise-induced elevation group was significantly higher (6.0±4.1 vs. 2.7±3.9mmHg, p&lt;0.001, in the older (age≥60y.o) group (n=276); 3.4±3.5 vs. 1.9±3.4mmHg, p&lt;0.001, in the younger (age&lt;60y.o) group (n=203)) than that in the non-elevation group after legs raise for cycle ergometer exercise. The area under the ROC curve for ΔPAWP was 0.72 (95% CI: 0.65–0.78) in the older and 0.64 (95% CI: 0.53–0.75) in the younger. In the older, the cut-off value for detect exercise-induced PAWP elevation of ΔPAWP was 4mmHg, with 72% sensitivity and 58% specificity. On the other hand, in the younger, the cut-off value was 3mmHg, with 69% sensitivity and 59% specificity.

Conclusion

Leg raise can easily detect occult left ventricular diastolic dysfunction.

Funding Acknowledgement

Type of funding source: None

Leadless pacemaker implant in patients with a history of open heart surgery: experience with the Micra transcatheter pacemaker

Background

The Micra transcatheter pacemaker has demonstrated a favorable safety and efficacy profile relative to transvenous pacing. Patients with a history of open heart surgery have a higher risk of complications with transvenous pacemakers during follow-up. The experience with leadless pacemakers among a large cohort of patients with a history of open heart surgery has not been reported.

Objective

To report outcomes in patients with a history of open heart surgery undergoing Micra implant.

Methods

Patients undergoing Micra implant from the Micra Transcatheter Pacing Post-Approval Registry (PAR) were included in the analysis. Baseline and procedural characteristics, major complications, and electrical performance were compared among patients with vs. without history of cardiac surgery.

Results

A total of 331 out of 1815 (18.2%) patients had a history of open heart surgery, underwent Micra implant, and were followed for 19.4±10.4 months. The mean age was 74.6±13.5 years, 40% were female. The most common cardiac surgery was aortic valve surgery (71%) followed by mitral valve surgery (39%). Patients with prior open-heart surgery were more likely to have contraindications to transvenous pacing, were more likely to be on oral anticoagulants, and had more co-morbidities including atrial fibrillation, heart failure, and coronary artery disease (all p&lt;0.005). Implantation was successful in 327 of 331 patients (98.8%) with a median procedure time of 29 minutes. Mean pacing capture thresholds (PCTs) at implant were 0.66±0.51V and remained stable through follow-up. There were 11 major complications in 10 cardiac surgery patients, with no device or procedure-related infections reported. The major complication rate was 3.1% (Figure) and was not significantly different than that of patients without a history of open heart surgery (HR: 0.85, P=0.640). There was 1 cardiac perforation (with no intervention required) in the open heart surgery group (0.3%) and there were 14 cardiac perforations (0.94%, P=0.332) in the non-open heart surgery group of which 10 required intervention.

Conclusion

The Micra transcatheter pacemaker can be safely implanted in patients with a history of open heart surgery, with a similar long-term safety profile to patients without a history of open heart surgery. Importantly, there were no device-related infections reported in either group.

Risk of Major Complication

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Medtronic, Inc.

Comparison of pulmonary vascular resistance and pulmonary artery compliance during exercise between IPAH and CTEPH with normal pulmonary artery pressure

Background

Pulmonary vascular resistance (PVR) and pulmonary artery compliance (PAC) are inversely related. However, the little is known about dynamics during exercise by disease difference. The aim of this study was to reveal the relationships of PVR and PAC during exercise between idiopathic pulmonary arterial hypertension (IPAH) and chronic thromboembolic pulmonary hypertension (CTEPH) patients.

Methods

Sixty-two IPAH patients (45±9 y.o) and 359 CTEPH patients (63±13 y.o) with normal mean PAP and PAWP at rest underwent symptom-limited exercise test using supine cycle ergometer with right heart catheter.

Results

There were no differences between baseline mean PAP and PAWP in 2 groups, however, cardiac output, SaO2 and SvO2 were lower in CTEPH group. Lower PAC (2.9±1.1 vs. 3.7±1.7 ml/mmHg, p&lt;0.001) and higher PVR (2.3±1.0 vs. 1.9±1.0 wood.unit, p=0.016) were observed in CTEPH group. These trends were also seen at peak exercise. PVR-PAC relationship in CTEPH group was leftward shift compared with IPAH group (Figure 1).

Conclusion

Resting and exercise PVR and PAC in CTEPH patients were worse than those in IPAH patients who had normal PAP and PAWP at rest.

Figure 1

Funding Acknowledgement

Type of funding source: None

Usefulness of peripheral-pressure-directed balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension

Background

Balloon pulmonary angioplasty (BPA) in expert center may be considered in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who are technically non-operable for pulmonary endarterectomy. BPA based on objective quantitative methods has not been established. The endpoint at BPA sessions has not been clarified yet.

Objectives

The purpose of this study was to investigate the usefulness of BPA according to peripheral pressure measured by pressure wire or catheter.

Methods

This study included consecutive 143 CTEPH who underwent cardiopulmonary exercise test with right heart catheterization after BPA. All patients were divided into 2 groups such as angio-guided (n=47) group or pressure-guidedgroup (n=96). In pressure-guided group, the pulmonary arterial pressure (PAP) proximal and distal to the target lesion and the ratio of the 2 pressures were measured by the pressure wire or catheter. the endpoint was determined to when the pressure ratio of distal to proximal pressures was &gt;0.7 to 0.8 finally. The dilation was stopped when the distal mean PAP after each dilation reached 35 mm Hg and when the baseline mean PAP was &gt;35 mm Hg. Changes of hemodynamic parameters such as PAP and pulmonary vascular resistance (PVR) from baseline, and mean PAP and PVR at peak oxygen consumption, and pulmonary arterial pressure – cardiac output (PA-CO) slope were compared between two groups. All data except changes of hemodynamics from baseline were expressed by median [25th percentile-75th percentile]. Changes of hemodynamics from baseline were expressed by average [95% confidence interval]

Results

The median age and male were 66 [56–72] years old and 35. There were no significant differences in number of sessions and dilated vessels between two groups (Angio-guided group vs. Pressure-guided group: 4 [3–6] vs. 4 [3–5], P&gt;0.05; 19 [12–22] vs. 17 [13–22], P&gt;0.05). Changes of PAP and PVR from baseline in pressure-guided group was significantly higher than in angio-guided groups (Angio-guided group vs. Pressure-guided group; ΔPAP: −19 [−20 to −17] vs. −20 [−21 to −20], P&gt;0.05; ΔPVR: −6.0 [−6.3 to −5.7] vs. −6.6 [−6.8 to −6.3], P&lt;0.01). Mean PAP and PVR at peak oxygen consumption (VO2) and PA-CO slope in pressure-guided group were significantly lower than in angio-guided group (Angio-guided group vs. Pressure-guided group; PAP at VO2: 43 [36–50] vs. 39 [34–43], P&lt;0.05; PVR at VO2: 2.7 [1.9–4.5] vs. 2.2 [1.6–2.9], P&lt;0.01; PA-CO slope: 3.8 [2.1–5.2] vs. 2.9 [1.9–4.0], P&lt;0.05).

Conclusions

Peripheral-pressure-directed BPA can improve hemodynamics at rest and exercise more effectively.

Funding Acknowledgement

Type of funding source: None

P942 Outcome prediction by exercise stress echocardiography and cardiopulmonary exercise testing assessment in patients with heart failure

Background

Cardiopulmonary exercise testing (CPX) is essential to the assessment of functional impairment and prognosis in patients with heart failure (HF). Peak oxygen consumption (peak VO2) continues to be considered the gold standard for assessing prognosis in HF. The minute ventilation-carbon dioxide production (VE-VCO2) slope has recently demonstrated prognostic significance in patients with HF. Ergometer stress echocardiography (Erg-Echo) is useful to evaluate the exercise-induced pulmonary hypertension and the potential cardiac dysfunction that are difficult to evaluate in the resting state.

Objective

The aim of this study is to evaluate the relationship between CPX and Erg-echo indices, and the usefulness of Erg-echo to determine the severity of cardiac dysfunction and the prognosis in patients with HF.

Methods

We studied 58 patients with HF (age 65.2 ± 11.9 years) and performed CPX and Erg-Echo. The peak VO2 and the VE-VCO2 slope were measured by CPX. Cardiac output (CO) and estimated mean pulmonary artery pressure (mPAP) were measured by Erg-Echo at rest and peak exercise load, and the change ratio (ΔmPAP / ΔCO) were calculated. We evaluated the clinical outcome during a1 year period.

Results

The ΔmPAP / ΔCO was significantly correlated with the peak VO2 (R = -0.6767, P &lt;0.0001) and the VE-VCO2 slope (R = 0.6809, P &lt;0.0001). Cardiovascular events (1 patient of cardiovascular death, 8 patients of re-hospitalization due to HF, 4 patients of myocardial ischemia, 2 patients of Cardiac Resynchronization Therapy (CRT) devices implantation, 1 patient of ventricular tachycardia) developed in 16 of the 58 patients (27.5%: Group CE) during the 1 year. The peak VO2 was significantly lower (12.1 ± 2.5 vs. 16.1 ± 3.1ml/min/kg, P &lt;0.0001) and the VE-VCO2 slope was significantly higher (41.1 ±. 12.3 vs. 31.8 ± 6.1ml/ml, P &lt;0.0001) in Group CE compared to the other 42 patients (Group N). The ΔmPAP was significantly higher (19.1 ± 4.4 vs. 14.9 ± 6.4, P = 0.0408) and the ΔCO was significantly lower (2.4 ± 1.2 vs. 4.1 ± 2.0, P = 0.0078), and the ΔmPAP / ΔCO was significantly higher (9.7 ± 4.6 vs. 4.4 ± 2.4, P &lt;0.0001) in Group CE compared to Group N.

Conclusions

The ΔmPAP/ ΔCO by Erg-Echo is useful to evaluate the severity of cardiac dysfunction and the prognosis of HF patients.

P1802 Prevalence and prognostic significance of pulmonary artery aneurysms in patients with pulmonary artery hypertension

Background

Pulmonary artery aneurysm (PAA) occurs in some patients with pulmonary arterial hypertension (PAH) and can be accompanied by various complications.

Objective

The aim of the this study is to evaluate the characteristics of cardiac dysfunction and the prognostic impact of PAA by analysing the outcome of patients with PAH complicated by PAA.

Methods

We performed echocardiography and right-heart catheterization in 130 PAH patients. We measured the maximum dimensions of the main pulmonary artery (MPA) trunk. We evaluated the right ventricular (RV) function and the five-year prognosis of patients with PAA.

Results

The maximum MPA trunk diameter of &gt;40 mm by echocardiography was defined as PAA. PAA appeared in 32 of the 130 PAH patients (24.6%: Group PAA), other 98 patients were defined as Group non-PAA. Systolic pulmonary artery pressure (76 ±18 vs. 61 ± 21 mmHg, P = 0.0008) and mean right atrial pressure (10.0 ± 8.1 vs. 5.4 ± 3.8 mmHg, P &lt; 0.0001) were significantly higher in Group PAA than in Group non-PAA. RV end-diastolic area index was significantly larger (37.3 ± 8.8 vs. 32.3 ± 7.8 mmHg, P = 0.0048), and RV fractional area change (32 ± 8 vs. 36 ± 9 %, P = 0.0176) and RV longitudinal strain amplitude (-16 ±5 vs. -20 ± 6, P = 0.0017) were significantly lower in Group PAA than those in Group non-PAA. During the five-year follow-up period, 20 patients (15%) died. The five-year mortality rate was significantly higher in Group PAA compared to Group non-PAA (30% vs. 10%, P = 0.007).

Conclusion

In PAH patients with PAA, RV dysfunction was more severe and the prognosis was poor. Assessment of PAA can be a useful index for the extraction of high-risk PAH patients.

P1825The characteristics of type A acute aortic dissection in patients with out-of-hospital cardiopulmonary arrest analyzed by computed tomography

Background/Introduction

Acute aortic dissection (AAD) is a life-threatening condition associated with high morbidity and mortality rates, and is reported to have a 1–2% fatality rate per hour after onset. Therefore, many cases with AAD are considered to be included in patients with out-of-hospital cardiopulmonary arrest (OHCPA). However at this time, there is a lack of documentation of these cases.

Purpose

In this study, we investigated the characteristics of Stanford type A AAD (TAAD) cases between OHCPA cases and survival cases using acute phase CT.

Methods

An acute phase CT scanning was performed on consecutive patients with OHCPA transported to our hospital in order to estimate the causes of cardiopulmonary arrest (CPA). Based on our emergency outpatient databases, we retrospectively reviewed the acute phase CT findings of OHCPA TAAD cases and survival TAAD cases diagnosed at our hospital during the same period.

Results

Of 1,011 consecutive patients with OHCPA, except for exogenous death from 1 January 2015 to 31 December 2017, 934 patients underwent CT examination in the acute phase. Based on the clinical course and CT findings, 71 of the 934 patients (7.6%) were diagnosed with AAD. Out of 71 AAD patients, 66 were TAAD patients, and all of these patients were enrolled in the OHCPA group. On the other hand, 41 patients were registered as the survival group during the same period. These patients were diagnosed as TAAD and were admitted to our hospital without falling into CPA. Increased Age (78±8 years old vs 69±13 years old, P<0.01), visible intimal flap (63.6% vs 41.5%, P=0.043), bloody pericardial effusion (72.7% vs 26.8%, P<0.01), hemothorax (24.2% vs 0%, P<0.01) were significant in patients with the OHCPA group compared with the survival group. In addition, 56 patients with OHCPA (84.8%) had at least one of massive bloody pericardial effusion or massive hemothorax. Using multivariate logistic regression analysis, increased age and bloody pericardial effusion were both found to be independent factors related to OHCPA.

Conclusion

In this study, it is thought that the main characteristics of the CT findings with OHCPA due to TAAD are a rupture of the aorta into the pericardial cavity or thoracic cavity.

5970Morbidity and mortality in patients precluded for transvenous pacemaker implantation: experience with the Micra transcatheter pacemaker

Background

The Micra transcatheter pacemaker has proven to be a safe and effective alternative to transvenous pacemakers (TVPs). However, the safety profile after Micra implantation in patients deemed poor candidates for TVPs is poorly understood.

Purpose

To evaluate the safety and all-cause mortality outcomes in Micra recipients stratified by whether or not they were precluded for therapy with TVP.

Methods

Micra patients from the Micra Transcatheter Pacing (IDE) Study, Continued Access (CA) study, and Post-Approval Registry (PAR) were divided into groups based upon whether or not the implanting physician considered the patient to be precluded from receiving a transvenous pacing system. All-cause mortality was compared between the Micra patient groups and patients receiving a single-chamber transvenous pacing system (SC-TVP) since 2010 from the Medtronic product surveillance registry using univariate and multivariate Cox models.

Results

Among 2,819 patients who underwent a Micra implant attempt, the overall major complication rate through 24 months was 3.5%. In these patients, 548 were deemed precluded from TVP implantation. Prior device infection or bacteremia (38.9%), venous access issues (36.1%) and thrombosis (10.2%) were amongst the most common causes of preclusion for TVP implantation. These patients were younger (71.7 vs. 76.7 years), more frequently on hemodialysis (26.3% vs. 2.5%), and more often had a prior CIED implanted (38.4% vs. 4.4%) than non-precluded patients. Over an average follow-up of 13.5±11.1 months, all-cause mortality was significantly higher in precluded Micra patients compared with SC-TVP patients (HR: 2.16, 95% CI: 1.54–3.2, P<0.001) (Figure 1). However, there was no significant difference in all-cause mortality when comparing non-precluded Micra patients and SC-TVP patients (HR: 1.12, 95% CI: 0.86–1.44, P=0.401). Acute all-cause death (within 1 month) among Micra patients was 2.74% and 1.32% in the precluded and non-precluded TVP groups, respectively. The procedure-related death rate was 0.55% for the TVP precluded group and 0.13% for the not precluded group (P=0.092). The major complication rate through 24-months was similar between the two Micra groups (4.0% vs 3.4%, P=0.630).

All-cause mortality for Micra and SC-TVP

Conclusion

The overall safety profile of Micra remains is in line with previously reported data. All-cause mortality risk (both acute and long term) appears to be higher in patients who were precluded from receiving TVP.

Acknowledgement/Funding

Supported by Medtronic

Prognostic value of plasma von Willebrand factor-cleaving protease (ADAMTS13) antigen levels in patients with coronary artery disease

High plasma level of von Willebrand factor (VWF) is a marker of future cardiovascular events in patients at high risk of coronary artery disease (CAD). The purpose of this study was to examine the changes and the prognostic value of plasma VWF-cleaving protease (ADAMTS13) levels in patients with CAD. Plasma VWF and ADAMTS13 levels were measured in 225 patients with CAD (152 men and 73 women, age, 70.3 ± 8.9 years, mean ± SD) and 100 patients without CAD who were ageand gender-matched to the CAD patients (60 men and 40 women, age, 68.6 ± 8.9 years). The CAD patients had higher VWF and lower ADAMTS13 antigen levels compared to patients without CAD. During 22.3 ± 10.4 months follow-up period, 20 major adverse cardiac and cerebrovascular events (MACCE) occurred in 222 patients with CAD who could be followed up. Kaplan-Meier analysis demonstrated that CAD patients with high plasma VWF antigen levels were significantly more likely to develop MACCE. Furthermore, eight cardiac and cerebrovascular thrombotic events [acute coronary syndrome (n=4) and cerebral infarction (n=4)] occurred in CAD patients with both high plasma VWF and low ADAMTS13 antigen levels. Multivariate Cox hazards regression analysis identified high plasma VWF and low ADAMTS13 antigen levels as significant and independent predictors of future MACCE and thrombotic events during the follow-up period in CAD patients. Our findings suggest that low plasma ADAMTS13 as well as high VWF level is a useful predictor of cardiac and cerebrovascular events in CAD patients.

Factor X Deficiency with Heterozygous Mutations of Novel p.G435S and Known p.G244R in a Patient Presenting with Severe Umbilical Hemorrhage

A 10-day-old male patient was referred to our hospital with severe umbilical bleeding. Prothrombin time (PT) and activated partial thromboplastin time (APTT) were prominently prolonged. Plasma coagulation factor X (FX) activity and antigen levels were 1% and 0.6%, respectively. A DNA sequence analysis of his leukocytes revealed a compound heterozygous state; known Gly244 to Arg (p.G244R) in exon 6 and a novel mutation of Gly 435 to Ser (p.G435S) in exon 8. A pedigree analysis showed that p.G244R originated from the paternal side, while p.G435S was from the maternal side. A p.G244R mutation was reported previously as FX_Debrecen and this mutated protein was synthesized as a non-secretable protein. The glycine at amino acid position 435 in the C-terminal region is completely conserved in the trypsin-like serine protease family, including thrombin, FVII, protein C, plasmin, trypsin, and chymotrypsin. In a three-dimensional structural model of FX, Gly 435 was located within the 11^th β-strand and buried in the back of the catalytic pocket. Therefore, the substitution to serine was expected to disrupt this structure. p.G435S FX was also predicted to be synthesized and exist in the cytoplasm, but not to be secreted into culture media by a cDNA expression assay. These two mutations may be responsible for the type 1 (null levels of both activity and antigen in plasma) FX deficiency with severe bleeding phenotype.

Force-induced IL-8 from Periodontal Ligament Cells Requires IL-1β

During orthodontic tooth movement, mechanical stresses induce inflammatory reactions in the periodontal ligament (PDL). We hypothesized that chemokines released from PDL cells under mechanical stress regulate osteoclastogenesis, and investigated the profiles and mechanisms of chemokine expression by human PDL cells in response to mechanical stress. In vitro, shear stress and pressure force rapidly increased the gene and protein expressions of IL-8/CXCL8 by PDL cells. Consistently, amounts of IL-8 in the gingival crevicular fluid of healthy individuals increased within 2 to 4 days of orthodontic force application. The PDL cells constitutively expressed low levels of IL-1β, which were not further increased by mechanical stress. Interestingly, neutralization of IL-1β abolished IL-8 induction by mechanical stresses, indicating that IL-1β is essential for IL-8 induction, presumably though autocrine or paracrine mechanisms. Finally, experiments with signal-specific inhibitors indicated that MAP kinase activation is essential for IL-8 induction.

Novel Antibody for the Treatment of Transthyretin Amyloidosis

Familial amyloidotic polyneuropathy (FAP) is a systemic amyloidosis mainly caused by amyloidogenic transthyretin (ATTR). This incurable disease causes death ∼10 years after onset. Although it has been widely accepted that conformational change of the monomeric form of transthyretin (TTR) is very important for amyloid formation and deposition in the organs, no effective therapy targeting this step is available. In this study, we generated a mouse monoclonal antibody, T24, that recognized the cryptic epitope of conformationally changed TTR. T24 inhibited TTR accumulation in FAP model rats, which expressed human ATTR V30M in various tissues and exhibited non-fibrillar deposits of ATTR in the gastrointestinal tracts. Additionally, humanized T24 (RT24) inhibited TTR fibrillation and promoted macrophage phagocytosis of aggregated TTR. This antibody did not recognize normal serum TTR functioning properly in the blood. These results demonstrate that RT24 would be an effective novel therapeutic antibody for FAP.

Quantification of venous reflux parameters using duplex scanning and air plethysmography

Objective: To compare different duplex-and air plethysmography (APG)-derived parameters between patients with relatively early and those with advanced chronic venous insufficiency (CVI), and to investigate the indicative parameters reflecting the progression of CVI.

Methods: Design: Prospective study at the University Hospital. Patients: In total 686 limbs in 574 patients at various clinical stages of CVI were included. The clinical manifestations were categorized according to the CEAP (clinical, aetiologic, anatomic and pathophysiologic) classification, and the patients were divided into two groups: group I (C1-3EP,SAS,D,PPR,O, relatively early stage of CVI) and group II (C4-6EP,SAS,D,PPR,O, advanced CVI). The distribution of venous insufficiency including the sapheno-femoral junction (SFJ), great saphenous vein (GSV), sapheno–popliteal junction (SPJ), common femoral vein (CFV), femoral vein (FV), popliteal vein (POPV), thigh perforators (TPV) and calf perforators (CPV) was determined by duplex ultrasound. The main duplex-derived parameters assessed were the reflux time (RT; s), peak reflux velocity (PRV; cm/s) and peak reflux flow (PRF; mL/s). The venous reflux was assumed to be present if the duration of reflux was ≥0.5 s. The data obtained by APG were on VV (mL), VFI (mL/s), EF (%) and RVF (%).

Results: There was no significant difference in overall superficial venous reflux between the groups ( P=0.331). The frequency of deep and perforating vein incompetence differed only when superficial reflux was included in group II. The VFI and RVF were significantly higher in secondary CVI than in primary CVI ( P=0.0001, 0.003, respectively). In the secondary CVI, patients with reflux and obstruction showed significantly higher RVF than those with reflux alone ( P=0.003). The RT did not improve the discrimination power between the groups. In contrast, the PRV had significant discrimination power at the SFJ ( P<0.0001) and SPJ ( P=0.022), and in the GSV ( P<0.0001), the FV ( P=0.017), and the POPV ( P=0.0003). The PRF was significantly higher in group II at the SFJ ( P<0.0001), in the GSV ( P=0.002), in the CFV ( P=0.011), in the FV ( P=0.027), and the POPV ( P=0.016).

Conclusions: This present study has suggested the importance of superficial venous insufficiency in the development of advanced CVI. In the secondary CVI, obstruction affects the RVF alone. The PRV and PRF are better parameters than the RT for discrimination of clinical severity in both superficial and deep venous insufficiency, and should be used to quantify venous valvular insufficiency.

Harvesting epithelial keratinocyte sheets from temperature-responsive dishes preserves basement membrane proteins and improves cell survival in a skin defect model

Cultured epithelial autograft (CEA) therapy has been used in clinical applications since the 1980s. However, there are some issues related to this treatment that still remain unsolved. Enzymatic treatment is typically used in the collection of epithelial keratinocyte sheets, but it tends to break the adhesion and basement membrane proteins. It is thought that the loss of proteins after enzymatic treatment is responsible for the poor survival of transplanted cell sheets. Our laboratory has developed a temperature-responsive culture dish that does not require enzymatic treatment to harvest the cells. In this study, we compare morphological and survival results from rat epithelial keratinocyte cell sheets harvested by temperature-reducing treatment (TT sheets) against cell sheets harvested by enzymatic (dispase) treatment (DT sheets). TT sheets preserve keratin structure in better conditions and express higher levels of collagen IV and laminin 5 than DT sheets. In order to evaluate cell sheet survival after transplantation, we created an in vivo transplant model. Keratinocyte sheets obtained from GFP-positive animals were transplanted into athymic rats. The survival rate 7 days after transplantation of TT sheet was higher than that of DT sheets. Collagen IV and Laminin 5 expression was observed in the TT sheet transplantation group. These results indicate that the remaining basement membrane proteins are important for initial attachment and cell survival. We believe that the cell sheet harvesting method using temperature-responsive culture dishes provides superior cell survival and can solve one of the roadblocks in CEA therapy. Copyright © 2016 John Wiley & Sons, Ltd.

Linker regions and flexibility around the metalloprotease domain account for conformational activation of ADAMTS-13

BACKGROUND

Recently, conformational activation of ADAMTS-13 was identified. This mechanism showed the evolution from a condensed conformation, in which the proximal MDTCS and distal T2-CUB2 domains are in close contact with each other, to an activated, open structure due to binding with von Willebrand factor (VWF).

OBJECTIVES

Identification of cryptic epitope/exosite exposure after conformational activation and of sites of flexibility in ADAMTS-13.

METHODS

The activating effect of 25 anti-T2-CUB2 antibodies was studied in the FRETS-VWF73 and the vortex assay. Cryptic epitope/exosite exposure was determined with ELISA and VWF binding assay. The molecular basis for flexibility was hypothesized through rapid automatic detection and alignment of repeats (RADAR) analysis, tested with ELISA using deletion variants and visualized using electron microscopy.

RESULTS

Eleven activating anti-ADAMTS-13 antibodies, directed against the T5-CUB2 domains, were identified in the FRETS-VWF73 assay. RADAR analysis identified three linker regions in the distal domains. Interestingly, identification of an antibody recognizing a cryptic epitope in the metalloprotease domain confirmed the contribution of these linker regions to conformational activation of the enzyme. The proof of flexibility around both the T2 and metalloprotease domains, as shown by by electron microscopy, further supported this contribution. In addition, cryptic epitope exposure was identified in the distal domains, because activating anti-T2-CUB2 antibodies increased the binding to folded VWF up to ~3-fold.

CONCLUSION

Conformational activation of ADAMTS-13 leads to cryptic epitope/exosite exposure in both proximal and distal domains, subsequently inducing increased activity. Furthermore, three linker regions in the distal domains are responsible for flexibility and enable the interaction between the proximal and the T8-CUB2 domains.

Electron reemission processes following photoelectron recapture due to post-collision interaction in inner-shell photoionization of water molecules

Electron reemission following photoelectron recapture due to post-collision interaction has been studied at 0.7 eV the inner-shell photoionization threshold of water molecules, using a multi-electron coincidence method. Electron reemissions after single Auger decay occur from O and OH fragments which are produced by the dissociations of high-n Rydberg H2O(+) states populated through photoelectron recapture. In addition, electron reemissions after double Auger decay are identified in triple coincidence events, where autoionization lines from O and O(+) fragments are observed.

Single photon K(-2) and K(-1)K(-1) double core ionization in C(2)H(2n) (n=1-3), CO, and N(2) as a potential new tool for chemical analysis

We have observed single photon double K-shell photoionization in the C(2)H(2n) (n=1-3) hydrocarbon sequence and in N(2) and CO, using synchrotron radiation and electron coincidence spectroscopy. Our previous observations of the K(-2) process in these molecules are extended by the observations of a single photon double photoionization with one core hole created at each of the two neighboring atoms in the molecule (K(-1)K(-1) process). In the C(2)H(2n) sequence, the spectroscopy of K(-1)K(-1) states is much more sensitive to the bond length than conventional electron spectroscopy for chemical analysis spectroscopy based on single K-shell ionization. The cross section variation for single photon K(-1)K(-1) double core ionization in the C(2)H(2n) sequence and in the isoelectronic C(2)H(2n), N(2) and CO molecules validates a knock-out mechanism in which a primary ionized 1s photoelectron ejects another 1s electron of the neighbor atom. The specific Auger decay from such states is clearly observed in the CO case.

ADAMTS13 unbound to larger von Willebrand factor multimers in cryosupernatant: implications for selection of plasma preparations for thrombotic thrombocytopenic purpura treatment

BACKGROUND

Thrombotic thrombocytopenic purpura (TTP) is characterized by deficient ADAMTS13 activity. Treatment involves plasma exchange (PE). Both fresh-frozen plasma (FFP) and cryosupernatant (CSP) are used, but it remains to be determined which is more effective.

STUDY DESIGN AND METHODS

To analyze the interaction between von Willebrand factor (VWF) and ADAMTS13, we used large-pore isoelectric focusing (IEF) analysis followed by detection with anti-ADAMTS13 monoclonal antibody. FFP, CSP, cryoprecipitate (CP), and purified ADAMTS13 were analyzed for their effects on high shear stress-induced platelet aggregation (H-SIPA).

RESULTS

IEF analysis of normal plasma revealed three groups of ADAMTS13 bands with pI of 4.9 to 5.6, 5.8 to 6.7, and 7.0 or 7.5. Two band groups (pI 4.9-5.6 and 5.8-6.7) were found in plasma of a patient with Type 3 von Willebrand disease, in which VWF is absent, whereas no bands were found in plasma of a patient with congenital ADAMTS13 deficiency. Mixing these plasmas generated the bands at pI 7.0 or 7.5, representing the VWF-ADAMTS13 complex; these bands were absent in CSP. FFP and purified ADAMTS13 down regulated H-SIPA in a dose-dependent manner. However, CP did not inhibit H-SIPA in the initial phase, and the degree of inhibition at the endpoint was almost indistinguishable from those of the other two plasma products.

CONCLUSION

Both plasma products (FFP and CSP) are effective for PE in TTP patients. However, CSP may be more favorable, because it has lower levels of VWF and almost normal ADAMTS13 activity, but lower levels of ADAMTS13 in complex with larger VWF multimers.

Constitutive dimerization of glycoprotein VI (GPVI) in resting platelets is essential for binding to collagen and activation in flowing blood

The platelet collagen receptor glycoprotein VI (GPVI) has been suggested to function as a dimer, with increased affinity for collagen. Dissociation constants (K(d)) obtained by measuring recombinant GPVI binding to collagenous substrates showed that GPVI dimers bind with high affinity to tandem GPO (Gly-Pro-Hyp) sequences in collagen, whereas the markedly lower affinity of the monomer for all substrates implies that it is not the collagen-binding form of GPVI. Dimer binding required a high density of immobilized triple-helical (GPO)(10)-containing peptide, suggesting that the dimer binds multiple, discrete peptide helices. Differential inhibition of dimer binding by dimer-specific antibodies, m-Fab-F and 204-11 Fab, suggests that m-Fab-F binds at the collagen-binding site of the dimer, and 204-11 Fab binds to a discrete site. Flow cytometric quantitation indicated that GPVI dimers account for ~29% of total GPVI in resting platelets, whereas activation by either collagen-related peptide or thrombin increases the number of dimers to ~39 and ~44%, respectively. m-Fab-F inhibits both GPVI-dependent static platelet adhesion to collagen and thrombus formation on collagen under low and high shear, indicating that pre-existing dimeric GPVI is required for the initial interaction with collagen because affinity of the monomer is too low to support binding and that interaction through the dimer is essential for platelet activation. These GPVI dimers in resting circulating platelets will enable them to bind injury-exposed subendothelial collagen to initiate platelet activation. The GPVI-specific agonist collagen-related peptide or thrombin further increases the number of dimers, thereby providing a feedback mechanism for reinforcing binding to collagen and platelet activation.

Identification of epitopes on ADAMTS13 recognized by a panel of monoclonal antibodies with functional or non-functional effects on catalytic activity

INTRODUCTION

von Willebrand factor (VWF) cleavage by ADAMTS13 is mediated by multi-step interactions between their multi-domain structures. To clarify the relationship between inhibitory effects of monoclonal antibodies and epitopes on each ADAMTS13 domain, we analyzed how each ADAMTS13 domain contributes to catalyze VWF using a mouse anti-ADAMTS13 monoclonal antibody panel.

MATERIALS AND METHODS

FRETS-VWF73 assay was used to examine the effects of 14 anti-ADAMTS13 monoclonal antibodies on the catalytic activity of plasma ADAMTS13. Epitope mapping was performed using phage surface display. Libraries expressing peptide fragments of ADAMTS13 were screened with the monoclonal antibodies.

RESULTS

Eleven epitopes of 14 monoclonal antibodies were successfully defined. Three monoclonal antibodies recognizing metalloprotease or disintegrin-like domains strongly inhibited the catalytic activity and their epitopes were on Gln159-Asp166, Tyr 305-Glu327, and Asn308-Glu376. Five monoclonal antibodies recognizing TSP1-3 to -7 repeats showed weak inhibitory effects, and their epitopes were on Pro744-Ala806, Pro856-Cys864, Gln892-Gly940, Cys1007-Cys1072, and Gln1163-Asn1185. Four monoclonal antibodies recognizing the TSP1-1, TSP1-2, CUB1 or CUB2 domains had no inhibitory effects, and their epitopes, except that for TSP1-1, were Pro682-Cys742, Thr1200-Cys1213, and Gln1409-Glu1414. Two monoclonal antibodies recognizing cysteine-rich and spacer domains showed moderate inhibitory effects, but their epitopes were not determined.

CONCLUSIONS

We revealed the epitopes of 11 monoclonal anti-ADAMTS13 antibodies on each of the domains and clarified their association with inhibitory effects on VWF catalysis under static conditions. Catalytic activity correlated strongly with the epitopes on metalloprotease and disintegrin-like domains, weakly with those on TSP1-3 to -7 repeats, and negatively with those on TSP1-1, -2, and CUB domains.

Antibody therapy for familial amyloidotic polyneuropathy

Although it is believed that altered conformations exposing cryptic regions are intermediary and critical steps in the mechanism of transthyretin (TTR) amyloid formation, no effective therapy targeting this step is available. In this study, to establish the antibody therapy for familial amyloidotic polyneuropathy (FAP), we generated a monoclonal anti-TTR antibody, which specifically reacts with surface epitopes of TTR (MAb ATTR) and evaluated its binding affinity and specificity for TTR amyloid fibrils. MAb ATTR showed specific binding affinity for TTR amyloid fibrils, but not for native form of TTR. Moreover, MAb ATTR indeed showed the high consistency with Congo red positive areas in tissue specimens from FAP ATTR V30M patients, indicating that MAb ATTR showed binding affinity and specificity for TTR amyloid fibrils in vitro and in vivo. MAb ATTR may have a potential to suppress TTR amyloid deposition and become a candidate for the antibody therapy for FAP.

Effect of ADAM28 on carcinoma cell metastasis by cleavage of von Willebrand factor

BACKGROUND

A disintegrin and metalloproteinase 28 (ADAM28) is implicated in tumor growth and metastasis in human breast and non-small cell lung carcinomas. We explored the mechanism of ADAM28-mediated metastasis by searching for new substrates of ADAM28.

METHODS

We used a yeast two-hybrid system to screen the human lung cDNA library for ADAM28-binding proteins and identified von Willebrand factor (VWF) as a potential candidate. Binding was confirmed using yeast two-hybrid and protein binding assays, and ADAM28-mediated cleavage of VWF was analyzed by immunoblotting. Exogenous VWF-induced apoptosis in vitro was examined in human lung carcinoma (PC-9 and Calu-3), breast carcinoma (MDA-MB231 and MCF-7), renal cell carcinoma (Caki-2 and 769P), and hepatocellular carcinoma (HepG2) cells, and expression of ADAM28 was assessed by reverse transcription-polymerase chain reaction and immunoblotting. Effect on lung metastasis of PC-9 and MDA-MB231 cells was assessed by knockdown of ADAM28 expression using short hairpin RNAs (ADAM28-shRNA) and small interfering RNAs (ADAM28-siRNA), and inhibition of activity using neutralizing anti-ADAM28 antibody, in a mouse xenograft model by in vivo imaging (n = 9 mice per group). All statistical tests were two-sided.

RESULTS

ADAM28 could bind to and cleave native VWF. Cells with very low ADAM28 expression (MCF-7, 769P, and HepG2) were susceptible to VWF-induced apoptosis, whereas cells with high expression (PC-9, Calu-3, MDA-MB231, and Caki-2) were resistant. Knockdown of ADAM28 expression in PC-9 and MDA-MB231 cells by shRNA showed increased carcinoma cell apoptosis mainly in lung blood vessels and statistically significantly decreased lung metastasis at week 3 after injection (PC-9-control [n = 9 mice] vs PC-9-ADAM28-shRNA [n = 9 mice]: mean count = 198 × 10(6) vs 37 × 10(6) photons/s, difference = 161 × 10(6) photons/s, 95% confidence interval = 134 × 10(6) to 188 × 10(6) photons/s, P < .001). Similar inhibition of lung metastasis was observed with ADAM28-siRNA and anti-ADAM28 antibody.

CONCLUSION

ADAM28 cleaves and inactivates proapoptotic VWF in carcinoma cells and enhances lung metastasis probably by promoting carcinoma cell survival within the blood vessels.

Prospective randomised comparative study of visual foam sclerotherapy alone or in combination with ultrasound-guided foam sclerotherapy for treatment of superficial venous insufficiency: preliminary report

OBJECTIVE

The aim of the study is to compare ultrasound-guided foam sclerotherapy (UGFS: injection of foam sclerosant under ultrasound guidance) of the great saphenous vein (GSV) combined with visual foam sclerotherapy (VFS: injection of foam sclerosant under visual control) for varicose tributary veins and VFS alone in the treatment of GSV reflux.

DESIGN AND METHODS

A total of 133 limbs in 97 patients with GSV reflux were randomised to receive either VFS alone or VFS combined with UGFS. In both groups, 1% polidocanol foam was used. Assessments included duplex ultrasonography, evaluation of Venous Clinical Severity Scores (VCSS) and CEAP (clinical, etiologic, anatomic, and pathophysiologic) scores. Ultrasonographic inspection of the foam in the GSV was carried out during 5 min before compression was applied. The primary 'end' point of the study was obliteration of the GSV at 6 months.

RESULTS

A total of 51 limbs in 48 patients were treated with UGFS + VFS and the remaining 52 limbs in 49 patients were treated with VFS alone. There were no significant inter-group differences in patient age, male: female ratio, height, weight, body mass index, CEAP clinical scores or VCSS. The GSV diameter was 6.0 ± 1.7 mm (median ± interquartile range) in the UGFS + VFS group and 5.7 ± 1.6 mm in the VFS group (p = 0.419). The mean injected volume of foam for varicose tributary veins was 4 ± 2 ml in the UGFS + VFS group and 6 ± 2 ml in the VFS group, a significantly higher amount of foam being used in the latter (p < 0.001). However, the mean total amount of foam was greater in limbs treated with UFGS + VFS than in those treated with VFS alone (p = 0.017). Ultrasonographic inspection revealed complete vasospasm of the GSV in 37 (72.5%) limbs in the UGFS + VFS group and 29 (55.8%) in the VFS group during sclerotherapy (p = 0.097). At 6-month follow-up, complete occlusion was found in 23 limbs (45.1%) treated with UGFS + VFS and in 22 limbs (42.3%) treated with VFS. The difference between the two groups was not significant (p = 0.775). Reflux was absent in 30 limbs (58.8%) treated with UGFS + VFS and in 37 (71.2%) treated with VFS (p = 0.190). There was no inter-group difference in post-treatment VCSS (p = 0.223).

CONCLUSIONS

These results show that UGFS + VFS and VFS are equally effective for the treatment of GSV reflux, despite the lower volume of foam used for VFS alone.

P4-20-05: Inflammatory Breast Cancer: Comparison of Epidemiology, Biology, and Prognosis between Japan and the United States, a Hospital-Based Study

Background: Inflammatory breast cancer (IBC) is a challenging disease characterized by low incidence, rapid progression, and poor survival. The epidemiology of IBC has been slow to emerge, given that the rarity of IBC makes large prospective clinical trials difficult. Compared to non-IBC, well-established features of IBC include a younger age of onset and lower frequency of hormone receptor positivity. Higher body mass index (BMI) is a purported risk factor. Previous reports also suggest that IBC is associated with more racial disparities, including incidence and age at diagnosis. The epidemiology of IBC in East Asia, however, has not been investigated. We performed a comparative study of IBC in Japan versus the United States to determine its epidemiologic and clinical features and to evaluate the differences in epidemiological factors between the two countries.

Patients and Method: Patients who visited St. Luke's International hospital (SLIH) in Tokyo, Japan and The University of Texas MD Anderson Cancer Center (MDA) in Texas, USA between 2003 and 2009 were identified. Epidemiological and biological data were collected from electronic medical records. Patient and tumor characteristics were tabulated and stratified by hospital. Kaplan-Meier curves were created for survival estimates and log-rank test was used for cross-group comparisons. Cox proportional-hazard analysis was used to identify a subset of significant prognostic variables that related to overall survival.

Result: 34 patients at SLIH and 531 patients at MDA were identified. Mean age at diagnosis was 52 years old (range, 32–81, SD, 10.8) and 50 years old (range, 22–87, SD, 11.6), respectively (P=0.476). Mean BMI was 22.9 kg/m2 (range, 17.3−30.5, SD 3.3 ) and 31.0 kg/m2 (range, 13.6−88.9, SD, 7.8) respectively (P&lt;0.01). Clinical Staging was not significantly different; Stage IIIB 38.2%, Stage IIIC 26.5%, and Stage IV 32.4% at SLIH versus 48.6%, 23.7%, and 27.3% at MDA (P= 0.167). Estrogen receptor (ER) and progesterone receptor (PR) negative cases were, respectively, 50.0% and 64.7% at SLIH and 50.5% and 64.2% at MDA (ER, P= 0.935; PR, P=0.908). Her-2 over-expression cases were 38.2% at SLIH and 28.6% at MDA (P=0.174). A significant difference in nuclear grade was seen between SLIH and MDA: 20.6% at SLIH were Grade 3 versus 68.7% at MDA (P&lt;0.01). Median overall survival at SLIH was 3.6 years versus 2.3 years at MDA (P=0.570). No prognostic factors were associated with overall survival.

Conclusion: Though IBC at SLIH differed significantly from IBC at MDA by several epidemiologic and biologic factors, there was no significant difference in survival. To define the epidemiological, prognostic, and risk factors of IBC in Japan, as well as in the world, further studies are needed.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-20-05.

Evidence of single-photon two-site core double ionization of C2H2 molecules

We observe the formation in a single-photon transition of two core holes, each at a different carbon atom of the C2H2 molecule. At a photon energy of 770.5 eV, the probability of this 2-site core double ionization amounts to 1.6 ± 0.4% of the 1-site core double ionization. A simple theoretical model based on the knockout mechanism gives reasonable agreement with experiment. Spectroscopy and Auger decays of the associated double core hole states are also investigated.

Energy correlation among three photoelectrons emitted in core-valence-valence triple photoionization of Ne

The direct observation of triple photoionization involving one inner shell and two valence electrons is reported. The energy distribution of the three photoelectrons emitted from Ne is obtained using a very efficient multielectron coincidence method using the magnetic bottle electron spectroscopic technique. A predominance of the direct path to triple photoionization for the formation of Ne3+ in the 1s 2s2 2p4 configuration is observed. It is demonstrated that the energy distribution evolves with photon energy and indicates a significant difference with triple photoionization involving only valence electrons.

Natural history of Upshaw-Schulman syndrome based on ADAMTS13 gene analysis in Japan

Upshaw-Schulman syndrome (USS) is an extremely rare hereditary deficiency of ADAMTS13 activity, termed congenital TTP. The clinical signs are usually mild during childhood, often with isolated thrombocytopenia. But their symptoms become more evident when patients have infections or get pregnant. We identified 43 USS-patients in Japan, who ranged in age from early childhood to 79 years of age. Analysing the natural history of these USS patients based on ADAMTS13 gene mutations may help characterise their clinical phenotypes. Severe neonatal jaundice that requires exchange blood transfusion, a hallmark of USS, was found in 18 of 43 patients (42%). During childhood, 25 of 43 patients were correctly diagnosed with USS without gender disparity. These 25 patients were categorised as having 'the early-onset phenotype'. Between 15 and 45 years of age, 15 were correctly diagnosed, and, interestingly, they were all female. The remaining three patients were male and were diagnosed when they were older than 45 years of age, suggesting that they were 'the late-onset phenotype'. Two of these three males developed sudden overt TTP when they were 55 and 63 years old, respectively. These two men had two different homozygous ADAMTS13 gene mutations, p.R193W/p.R193W and p.C1024R/p.C1024R, respectively. Both of which were not discovered in the US or Western countries. In vitro expression studies showed that these two proteins were consistently secreted into the culture medium but to a lesser extent and with reduced activity compared to the wild-type protein. Our results indicate that 'the late-onset phenotype' of USS is formed with ethnic specificity.