Efficacy of repeated administration of intravenous acetaminophen for pain management after total knee arthroplasty

Intravenous acetaminophen is an integral component of multimodal postoperative pain management. This prospective study aims to assess the efficacy of the repeated administration of intravenous acetaminophen and the impact on postoperative patient satisfaction with postoperative pain management after total knee arthroplasty (TKA). We enrolled 98 patients scheduled for unilateral TKA. Patients were randomly assigned to receive either 1000 mg of intravenous acetaminophen at 6-hour intervals (AAP group) or not to receive intravenous acetaminophen (control group). All patients underwent single-shot femoral nerve block after general anesthesia, as well as intraoperative periarticular infiltration of analgesia prior to implantation. The primary outcome was the postoperative numerical rating scale (NRS) pain score at rest. The NRS score was measured just before the administration of study drugs, immediately after arrival in the ward (time 0), and at 6, 12, 18, 24, and 48 h (time 1 to time 5, respectively) postoperatively. We also evaluated the mean doses of rescue opioid use for 24 h postoperatively. At time 5, the AAP group had significantly improved mean NRS score than controls (3.0 vs. 4.0; P < 0.01). Rescue opioid use was significantly lower in the AAP group for 24 hours compared to controls (0.3 μg vs. 0.9 μg; P < 0.01). Repeated intravenous acetaminophen administration after TKA may provide better analgesia and reduce opioid use.

Search for the Majorana Nature of Neutrinos in the Inverted Mass Ordering Region with KamLAND-Zen

The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta (0νββ) decay half-life in ^{136}Xe using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of ^{136}Xe. These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the 0νββ decay half-life of T_{1/2}^{0ν}>2.3×10^{26}  yr at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36-156 meV using commonly adopted nuclear matrix element calculations.

POS0615 CLINICAL DEMOGRAPHICS AND FACTORS AFFECTING DRYNESS IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background

Sjogren’s syndrome (SS) is known to coexist with rheumatoid arthritis (RA). However, the prevalence of RA with SS varies widely, from 2.4% to 30%, and some patients with RA without SS also show dryness. The prevalence and clinical demographics of dryness in patients with RA are not well recognized.

Objectives

The aim of this study was to clarify the prevalence, clinical demographics, and related factors of dryness in patients with RA who have not been diagnosed with (SS).

Methods

We enrolled 166 patients with RA (129 females, 37 males; mean age 65.8±14.3 years; disease duration 14.1±10.9 years; DAS28-CRP 2.30±0.92) who were not diagnosed with SS. We analyzed CRP, the estimated glomerular filtration rate (eGFR), RF, anti-CCP antibody, antinuclear antibody, anti-SS-A antibody (SSA), and disease activity score (DAS) 28-CRP, and identified treatments for RA. We used each question item of the EULAR SS Patient Reported Index (ESSPRI) to clarify dryness, somatic and mental fatigue, and pain. History of smoking, comorbidities, such as interstitial pneumonia, fibromyalgia, and psychiatric disorders, and narcotic and/or psychotropic medication use were determined from the medical records. We defined patients with dryness as greater than or equal to one point, and those with severe dryness as greater than or equal to five points, of the visual analog scale (VAS).

Results

Dryness was observed in 93/166 (56.0%) patients and severe dryness was identified in 57/166 (34.4%) patients, and SSA was positive in 23/139 patients(13.9%). We divided our patients into dryness and non-dryness groups and compared their clinical demographics. The dryness group was relatively younger (64.0±14.5 vs. 68.1±13.8 years, p=0.052), had a female predominance (89.2% vs. 63.0%, p<0.001), had severe fatigue (4.06±2.59 vs 2.60±2.78, p<0.001), and had severe pain (3.52±2.41 vs. 2.73±2.32, p=0.020). However, the prevalence of SSA did not significantly differ in this cohort, compared with the non-dryness group (19.3% vs. 11.8%, p=0.248). Next, we analyzed the clinical characteristics of the patients with severe dryness. The severe dryness group was younger (61.9±15.5 vs. 67.9±13.2 years, p=0.022), had higher eGFR (76.1±15.5 vs. 68.9±22.7, p=0.020), had more severe fatigue (4.89±2.42 vs. 2.85±2.63), p<0.001), and had more severe pain (4.16±2.51 vs. 2.65±2.18, p<0.001), compared with non-severe dryness group. The prevalence of SSA was also significantly higher in the severe dryness group (91.2% vs. 70.6%, p=0.002). We then performed a multifactorial analysis using logistic regression analysis with a stepwise method. Female sex (OR 3.739, 1.247-11.207) and VAS of fatigue (OR 1.269, 1.054-1.526) were found to independently relate to dryness.

Conclusion

More than half of the patients with RA had dryness, although only 13.9% of patients were SSA positive. Dryness was related to female predominance and fatigue. Simon et al. reported that SS was found in 2.42% of patients with RA (1). On the other hand, Harrold et al. reported that SS was found in 30% of patients with RA, and the prevalence of SS increased with duration of RA (2). Our data indicate that patients with fatigue, regardless of pain, tend to have dryness, which may be a key factor in diagnosing SS in patients with RA.

References

[1]Simon TA, Kawabata H, Ray N, et.al. Prevalence of Co-existing Autoimmune Disease in Rheumatoid Arthritis: A Cross-Sectional Study. Adv Ther. 2017 Nov;34(11):2481-2490.

[2]Harrold LR, Shan Y, Rebello S, et al. Prevalence of Sjögren’s syndrome associated with rheumatoid arthritis in the USA: an observational study from the Corrona registry. Clin Rheumatol. 2020 Jun;39(6):1899-1905.

Disclosure of Interests

None declared

Molecular insights into the microtubules depolymerizing activity of the IL-8 receptor B antagonist SB225002

OBJECTIVE

We have previously reported the novel off-target microtubules destabilizing activity of SB225002, a compound that was originally designed as a selective and potent IL-8 receptor B antagonist. In the present study we investigated the reversibility of SB225002 antimitotic effect and provided additional mechanistic insights underlying cell death induction in SW480 human colorectal adenocarcinoma cells.

MATERIALS AND METHODS

Mitotically arrested cells by SB225002 treatment were isolated by shake-off, and their identity was verified by both flow cytometry and immunoblotting. The reversibility of SB225002 antimitotic effects was investigated by flow cytometry and immunoblotting. Prometaphase arrested cells were imaged via indirect immunofluorescence and confocal microscopy. Activation of CHK1 in mitotically arrested cells was assessed by immunoblotting, and the relationship between CHK1 and mitotic arrest was examined via siRNA-mediated knockdown of CHK1. JNK signaling was evaluated via immunoblotting as well as pharmacological inhibition, followed by flow cytometry. The role of reactive oxygen species (ROS) in cytotoxicity was evaluated by ROS scavenging and flow cytometry.

RESULTS

Following SB225002 washout, the mitotic checkpoint was abrogated, and cell cycle perturbations were gradually restored with induction of cell death. Mechanistically, CHK1 checkpoint was activated by SB225002 and occurred downstream of the mitotic checkpoint. In addition, SB225002 activated JNK signaling which contributed to cell death and restrained polyploidy. Furthermore, SB225002 increased intracellular ROS which played a role in mediating SB225002 cytotoxicity.

CONCLUSIONS

Findings of the present study warrants further development of SB225002 as a lead compound that uniquely targets microtubules dynamics and IL-8 signaling.

Interpretable AI Explores Effective Components of CAD/CAM Resin Composites

High flexural strength of computer-aided manufacturing resin composite blocks (CAD/CAM RCBs) are required in clinical scenarios. However, the conventional in vitro approach of modifying materials’ composition by trial and error was not efficient to explore the effective components that contribute to the flexural strength. Machine learning (ML) is a powerful tool to achieve the above goals. Therefore, the aim of this study was to develop ML models to predict the flexural strength of CAD/CAM RCBs and explore the components that affect flexural strength as the first step. The composition of 12 commercially available products and flexural strength were collected from the manufacturers and literature. The initial data consisted of 16 attributes and 12 samples. Considering that the input data for each sample were recognized as a multidimensional vector, a fluctuation range of 0.1 was proposed for each vector and the number of samples was augmented to 120. Regression algorithms—that is, random forest (RF), extra trees, gradient boosting decision tree, light gradient boosting machine, and extreme gradient boosting—were used to develop 5 ML models to predict flexural strength. An exhaustive search and feature importance analysis were conducted to analyze the effective components that affected flexural strength. The R2 values for each model were 0.947, 0.997, 0.998, 0.983, and 0.927, respectively. The relative errors of all the algorithms were within 15%. Among the high predicted flexural strength group in the exhaustive search, urethane dimethacrylate was contained in all compositions. Filler content and triethylene glycol dimethacrylate were the top 2 features predicted by all models in the feature importance analysis. ZrSiO4 was the third important feature for all models, except the RF model. The ML models established in this study successfully predicted the flexural strength of CAD/CAM RCBs and identified the effective components that affected flexural strength based on the available data set.

Muscle Evaluation and Hospital-Associated Disability in Acute Hospitalized Older Adults

OBJECTIVES

We aimed to examine the association of muscle evaluation, including muscle ultrasound, with hospital-associated disability (HAD), focusing on ADL categories.

DESIGN

A prospective observational cohort study.

SETTING AND PARTICIPANTS

We recruited patients aged 65 years or older who were admitted to the geriatric ward of an acute hospital between October 2019 and September 2021.

MEASUREMENTS

Handgrip strength, bioimpedance analyzer-determined skeletal muscle mass, bilateral thigh muscle thickness (BATT), and the echo intensity of the rectus femoris on muscle ultrasound were performed as muscle assessments. HAD was evaluated separately for mobility impairments and self-care impairments.

RESULTS

In total, 256 individuals (mean age, 85.2 years; male sex, 41.8%) were analyzed. HAD in mobility was more common than HAD in self-care (37.5% vs. 30.0%). Only BATT was independently associated with HAD in mobility in multiple logistic regression analysis. There was no significant association between muscle indicators and HAD in self-care.

CONCLUSION

A lower BATT was associated with a higher prevalence of HAD in mobility, suggesting the need to reconsider muscle assessment methods in hospitalized older adults. In addition, approaches other than physical may be required, such as psychosocial and environmental interventions to improve HAD in self-care.

Basic mechanism of atrial and ventricular arrhythmia suppression by heavy ion irradiation in hypercholesterolemic elderly rabbits

Background

Recent development of electrophysiology-guided noninvasive cardiac radioablation therapy for ventricular tachycardia attracts a great deal of attention as a novel antiarrhythmic strategy (Robinson CG, Circulation 2019). As to underlying mechanisms, however, much remains to be clarified. We reported before that a single targeted heavy ion irradiation (THIR 15Gy) to rabbit hearts increased connexin43 (Cx43) expression, and a reduction of vulnerability to ventricular arrhythmias after myocardial infarction.

Purpose

We investigated the effects of THIR on in-vivo cardiac electrophysiology and vulnerability to atrial and ventricular tachyarrhythmias in aged rabbits with hypercholesterolemia.

Methods

Sixteen three-year old rabbits were fed with high fat/cholesterol chow (0.5% cholesterol and 10% coconut oil) for 14 weeks. A single THIR 15Gy was applied to 8 rabbits (HC+THIR) with a heavy ion medical accelerator. Eight rabbits without THIR were used as control (HC).

Results

Serum cholesterol levels in the HC and HC+THIR were 1545+386 and 1569+328 mg/dl (n=8, NS). Atrial (P-wave) late potential in signal-averaged ECG in HC+THIR showed a significantly larger root mean square voltage (RMS) than those in HC (12+0.5 vs. 2+0.5μV, n=4, p&lt;0.01). Ventricular late potentials in HC+THIR showed significantly less fQRS-D than HC (81+5 vs. 89+7 ms); less LAS40 (21+7 vs. 30+4 ms), and larger RMS (99+27 vs. 44+13μV) (n=4, p&lt;0.04). Atrial tachycardia or fibrillation (AT/AF) was induced spontaneously or by programmed/burst pacing of the left atria (LA) in 4 out of 4 HC, whereas in only 1 out of 4 HC+THIR. Ventricular tachycardia or fibrillation (VT/VF) was induced spontaneously or by programmed pacing or left stellate stimulation in 4 out of 4 HC rabbits, whereas in only 1 out of 4 HC+THIR. Immunolabeled Cx40 densities in LA and RA tissue from HC+THIR rabbits were significantly higher than those from HC rabbits by 44% and 60%, respectively (n=4, p&lt;0.01). Comparable upregulation of immunoreactive Cx43 was observed in LV and RV tissue from HC+THIR rabbits. Sympathetic nerve densities in LA, RA, LV and RV tissues, which was labeled with anti-neuronal growth-associated protein 43 (GAP43) antibody and tyrosine hydroxylase (TH) antibody were both significantly less in HC+THIR than those in HC.

Conclusion

These results suggest that THIR may improve cardiac conductivity of HC rabbits in favor of reduction of vulnerability to atrial and ventricular tachycardia/fibrillation, and that this antiarrhythmic effect is attributed to upregulation of gap junction protein (Cx40 and Cx43) and in part to prevention of sympathetic nerve sprouting.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): KAKENHI KIBAN (C) 53020

A multivariate factor analysis of the high plasma concentration of cyclic AMP in patients with chronic renal failure

The concentration of cyclic AMP which is known as an intracellular mediator of hormone action increased in the plasma of patients with chronic renal failure (CRF). In the present study, the plasma concentration of cyclic AMP significantly correlated not only with serum, creatinine, and urea levels, but also with plasma PTH and glucagon in patients with CRF. Furthermore, plasma concentrations of PTH and glucagon correlated with the serum creatinine concentration to a significant extent.

To discuss the cause of the increased cyclic AMP concentration in plasma of patients with CRF, multivariate analyses were carried out on the obtained clinical data from patients and normal subjects. In the factor analysis on the clinical data from 61 subjects, cyclic AMP, creatinine and BUN correlated with the first factor and PTH correlated with the second factor. The cumulative contribution ratio by the second factor was 76%. The results of the cluster analysis indicated that cyclic AMP, creatinine, and BUN formed a cluster and PTH glucagon made another cluster. These results suggest that the elevated plasma concentration of cyclic AMP in patients with CRF was mainly introduced not by overproduction but by the retention of cyclic AMP due to the decreased renal function.

88 Severe tricuspid regurgitation due to papillary muscle rupture: A rare complication of anterior myocardial infarction and ventricular septal perforation

INTRODUCTION

Papillary muscle rupture (PMR) of the mitral valve is a fatal complication of acute myocardial infarction (MI). As a complication of anterior MI, PMR of the tricuspid valve is extremely rare. We experienced a case of acute anterior MI complicated with tricuspid PMR and ventricular septal perforation (VSP).

REPORT

An 85-year-old woman was admitted with general fatigue and appetite loss. Her consciousness was alert, but she was pale, and had cold extremities. Her blood pressure was 74/62 mmHg, and pulse was 99/min. There was no leg edema. Pan systolic regurgitant murmur (Levine III/VI) was audible at the lower left sternal border. Her oxygen saturation was 86% under room air. Electrocardiogram revealed ST segment elevation and QS pattern in V1 to V3. Transthoracic echocardiography revealed dyskinesis of the apical anterior septum, VSP with bidirectional shunt, and severe pulmonary hypertension. Left ventricular ejection fraction was preserved (58%). The anterior tricuspid leaflet was flail due to PMR, resulting in severe tricuspid regurgitation and right ventricular dilatation. Coronary angiography revealed a single vessel disease of the left anterior descending artery (LAD). We recommended surgical treatment, and transferred her to another hospital.

DISCUSSION

Common causes of tricuspid PMR are infective endocarditis and chest trauma. Right ventricular infarction, usually caused by right coronary artery (RCA) occlusion, may cause tricuspid PMR. In our case, however, tricuspid PMR was complicated with anterior MI. The tricuspid anterior, posterior, and septal leaflets are attached to anterolateral RV wall, inferior septum, and infundibular septum, respectively, via papillary muscles. Right ventricular branches and septal branches of the RCA usually supply these papillary muscles. Anterior leaflet PMR in this case was possibly due to anomalous blood supply of anterolateral RV wall by the right ventricular branches of the LAD. Right ventricular overload due to large VSP shunt elevated RV diastolic pressure and right atrial pressure, and might worsen ischemia of the RV wall.

Abstract 88 Figure. severe TR & shunt flow through VSP

Influence of Olfactory Function on Appetite and Nutritional Status in the Elderly Requiring Nursing Care

OBJECTIVE

To investigate olfactory function in elderly subjects requiring nursing care to clarify its association with appetite and nutritional status.

SETTING

Facility for the elderly requiring nursing care.

PARTICIPANTS

The subjects were 158 elderly people requiring nursing care and 37 elderly people not requiring nursing care.

MEASUREMENTS

Experiment I: Olfactory function and factors (cognitive function, appetite, and nutritional status) that may be associated with it were compared between the elderly subjects requiring nursing care and those not requiring nursing care using covariance analysis in consideration of age. For evaluation, the OSIT-J was used for olfactory function, the HDS-R for cognitive function, the CNAQ for appetite, and BMI for nutritional status. Experiment II: The subjects were the same elderly subjects requiring nursing care in Experiment I, and food intake was surveyed in addition to the OSIT-J, HDS-R, CNAQ, and BMI. A univariate linear regression analysis was performed with OSIT-J as the response variable, and age, HDS-R, CNAQ, BMI, and food intake as the explanatory variables.

RESULTS

Experiment I: On covariance analysis, the OSIT-J score was significantly lower for the elderly subjects requiring nursing care than for those not requiring nursing care (p<0.01). The mean score was 8 or lower in both groups, demonstrating lower olfactory function in both groups. Regarding factors that may be associated with olfactory function, a significant difference was noted in the HDS-R (p<0.01), confirming significantly lower cognitive function in the elderly subjects requiring nursing care. No significant difference was noted in the CNAQ or BMI. Experiment II: On a univariate linear regression analysis, an association with the OSIT-J was noted for age and HDS-R. Age was inversely correlated and the HDS-R was positively correlated. Factors associated with lower olfactory function in the elderly subjects requiring nursing were age and cognitive function, whereas appetite, nutritional status, and food intake were not associated.

CONCLUSION

Olfactory function in elderly subjects requiring nursing care was poorer than that in those not requiring nursing care, suggesting that aging and cognitive decline are associated with lower olfactory function. In addition, no association of lower olfactory function with appetite, nutritional status, or food intake was noted in the elderly subjects requiring nursing care.

Restoration of lead-inhibited 5-aminolevulinate dehydratase activity in whole blood by heat, zinc ion, and (or) dithiothreitol

We examined effects of heat, zinc, ion, and dithiothreitol in restoring the activity of lead-inhibited-5-aminolevulinate dehydratase (EC 4.2.1.24). The ratio of non-activated to activated activity produced by dithiothreitol correlated well with blood lead concentration among 35 lead workers. The individual effects of heat, zinc, or dithiothreitol differ from each other in the shift of pH optimum as well as in the extent to which activity is restored. Dual or triple combinations of these agents show additive or complementary restoration of activity. The combination of heat and zinc or zinc and dithiothreitol expands the range of optimum concentration of zinc in restoring activity. Using these combinations of agents, we can expect more accurate evaluation of lead exposure than by measuring only activation of zinc. Although dithiothreitol most powerfully restores activity, it restores not only the activity inhibited by lead exposure but also the activity removed by oxidation of SH-groups in the enzyme molecule.

Short-term safety and effectiveness of sugammadex for surgical patients with end-stage renal disease: a two-centre retrospective study

Sugammadex is a novel reversal agent for aminosteroid neuromuscular blocking drugs, especially rocuronium. Given its renal excretion, sugammadex is not recommended for patients with end-stage renal disease; however, reports exist of its use in this group of patients. This two-institutional retrospective observational study aimed to review the safety profile and effectiveness of sugammadex in surgical patients with end-stage renal disease who required pre-operative renal replacement therapy. Adult surgical patients with end-stage renal disease requiring pre-operative renal replacement therapy, who received sugammadex between April 2016 and January 2019, were studied. The primary outcome was the incidence of postoperative tracheal re-intubation within 48 h. The secondary outcome was the incidence of deferred tracheal extubation in the operating theatre. One hundred and fifty-eight patients were identified from 125,653 surgical patients: 48 patients (30%) underwent renal transplantation and 110 (70%) underwent non-renal transplantation procedures. There were 22 instances (14%) of deferred tracheal extubation due to surgical and/or pre-existing medical conditions. Out of the 136 patients who had the tracheal tube removed at the end of the procedure, three patients had their trachea re-intubated within 48 h: two patients developed pulmonary oedema resulting from volume overload; and one patient had worsening sepsis. No incidence of recurrence of neuromuscular blockade was observed. Of note, 24 (18%) patients were found to have incomplete neuromuscular blockade reversal with neostigmine but administration of sugammadex led to successful tracheal extubation. In conclusion, sugammadex appears to be safe and effective in adult patients with end-stage renal disease receiving pre-operative renal replacement therapy.

P943The impact of diabetes on patients with frail after endovascular treatments: from I-PAD registry

Background

Diabetes mellitus (DM) is known to be one of the risks of arteriosclerosis. However, it is still unknown whether DM is a risk factor also in secondary prevention of frail patients after endovascular treatments (EVT)

Purpose

To investigate impact of diabetes on patients with frail after EVT.

Methods

From July 2015 to July 2016, 371 consecutive PAD patients who performed EVT were enrolled in I-PAD registry. We could conduct follow up survey 361 patients (446 lesions) and divided into 2 groups; with diabetes (185 patients, 226 lesions) or without diabetes (176 patients, 220 lesions) and analyzed. And among them,we selected 96 patients with frail and divided into 2 groups; with diabetes (49 patients, 70 lesions) or without diabetes (46 patients, 58 lesions) and analyzed. We defined frail patients as the patients with Clinical Frailty Scale 5 (mild frail) or higher. The primary end point was all-cause-death and major adverse limb events (MALE: TLR, TVR, major amputations) at 1 year.

Result

At 1 years in the patients group with diabetes, overall survival and freedom from MALE were significantly lower (81.7% vs 95.8% P<0.0001; 80.0% vs 94.6%, P<0.0001) than the group without diabetes.Among the patients with frail, between the patients group with diabetes and the group without, there is no significant differences in overall survival and freedom from MALE (88.2% vs 88.9% P=0.83; 80.7% vs 84.1%, P=0.55) at 5 years.

Conclusion

The prognosis of patients with diabetes after EVT was worse than the patient without. On the other hand, the prognosis of frail patients with diabetes after EVT was no difference with the frail patient without diabetes in this study.

P599Native T1 mapping is useful for detection of myocardial fibrosis in cases with ischemic and non-ischemic myocardial diseases

Background

Evaluation of myocardial fibrosis (MF) as late gadolinium enhancement (LGE) on MRI is useful for differential diagnosis of various myocardial diseases and prediction of future adverse cardiac events in some specific myocardial diseases. Gadolinium contrast is contraindicated for cases with severe renal dysfunction, therefore non contrast MRI is necessary for detection of MF in cases with both myocardial disease and severe renal dysfunction.

Purpose

We aimed to evaluate diagnostic accuracy of native T1 mapping for detection of MF compared with LGE in cases with various myocardial diseases, including ischemic and non-ischemic myocardial diseases.

Methods

We selected consecutive 40 patients who were suspected of having various myocardial diseases and underwent cardiac MRI, using 1.5T MRI (Ingenia, Philips) in 10 cases (25%) or 3T MRI (Ingenia, Philips) in 30 cases (75%), including native T1 mapping (without contrast) and LGE using contrast media from Jan 2018 to Feb 2019 in our institution. We evaluated diagnostic accuracy for detection of MF in left ventricular myocardium (LVM) of native T1 mapping image compared with LGE as the gold standard, in a patient-based and segment-based analysis. In T1 mapping images, segmental high T1 lesions were defined as MF. In a segment-based analysis, MF was evaluated using 17 LVM segments model in American Heart Association.

Results

MF was detected in 139 LVM segments in 25 (63%) cases. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of native T1 mapping for detection of MF were 90%, 89%, 95%, 80% and 90% in a patient-based analysis, and 63%, 96%, 84%, 89% and 88% in a segment-based analysis (left figure). Native T1-values of LVM with MF were significantly higher than LVM without LGE (1351±79 vs 1093±124 in 1.5T and 1562±131 vs 1291±43 in 3T) (p<0.05 and p<0.01). Interobserver agreement of native T1 mapping and LGE were not significantly different (0.88 and 0.89, P=0.70). Overall diagnostic accuracy of native T1 mapping for detection of MF in a patient-based analysis, was not significantly different in between the cases with ischemic (n=18) and non-ischemic (n=22) myocardial disease (90% and 83.3%, P=0.10).

Conclusion

Native T1 mapping (without contrast) is useful for detection of MF in various myocardial diseases and high diagnostic accuracy is expected especially in a patient-based analysis.

P942Impact of left ventricular ejection fraction in patients with critical limb ischemia: from I-PAD registry

Introduction

In patients with critical limb ischemia (CLI) it is known that malnutrition, low BMI, inflammation and so on are prognostic factors. But, it is unclear whether left ventricular ejection fraction (LVEF) affects prognosis of CLI patients. So we investigated that LVEF affects prognosis of CLI patients.

Methods

From July 2015 to July 2016, 371 consecutive peripheral artery disease patients who performed endovascular treatment (EVT) were enrolled in I-PAD registry. 179 of them were patients with CLI. We could conduct follow up survey about 126 (age 75.5±11.1, men 63.5%) and divided two groups according to their LVEF (group with LVEF≤40%, n=13, group without LVEF≤40%, n=113). The primary end point was major adverse limb events (MALE: TLR, TVR, major amputations) and secondary end point was all-cause death.

Results

The median follow-up period was 11.5±6.7 months. The 18 months MALE rate was significant higher in the group with low LVEF than group without low LVEF (76.9% vs 37.2% p<0.05). The 18months all-cause death tended to be higher in the group with low LVEF, however there was not statistical significance in the two groups (53.8% vs 24.8% p=0.09).

Conclusion

LVEF was associated with MALE in patients with CLI.

P1957Impact of fraility on the super elderly patients with peripheral artery disease

Background

The current consensus is that frail patients have high risks of mortality. However, it remains unclear whether frailty is associated with mortality risks in super-elderly patients with peripheral artery disease (PAD).

Methods

The I-PAD registry was a prospective multicenter observational study involving 12 institutions in Nagano prefecture in Japan. From July 2015 to July 2016, the I-PAD registry enrolled 371 consecutive PAD patients who had undergone endovascular therapy (EVT). Among them, we selected and analysed 109 PAD patients who were >80 years old when they had undergone EVT and divided them into two groups: those with frailty (Clinical Frailty Scale≥5, n=47) and those without frailty (Clinical Frailty Scale≤4, n=62). The primary endpoints were overall survival and major adverse limb events (MALE), defined as a composite of all-cause death, major amputation and revascularization.

Results

The median follow-up period was 1.58±0.3 years. Overall, 109 patients with a mean age of 84.8±4.0 years, of whom 63.3% were men, were included. Overall survival and freedom from MALE were significantly lower among patients with frailty than among those without frailty (60.5% vs. 91.6%, P<0.001; 51.4% vs. 87.5%, P<0.001; respectively).

Conclusion

The prognosis of super-elderly patients with frailty is worse than that of patients without frailty.

P936Impact of left ventricular ejection fraction in patients with peripheral artery disease: from I-PAD registry

Introduction

In patients with peripheral artery disease (PAD) it is known that CVD is one of prognostic factors. But, it is unclear whether left ventricular ejection fraction (LVEF) affects prognosis of PAD patients. So we investigated that LVEF affects prognosis of PAD patients.

Methods

From July 2015 to July 2016, 371 consecutive PAD patients who performed endovascular treatment (EVT) were enrolled in I-PAD registry. We could conduct follow up survey about 337 (age 73.8±9.6, men 72.4%) patients and divided two groups according to their LVEF (group with LVEF≤40%, n=18, group without LVEF≤40%, n=319). The primary end point was major adverse limb events (MALE: TLR, TVR, major amputations) and secondary end point was all-cause death.

Results

The median follow-up period was 13.6±5.7 months. The 18 months MALE and all-cause death rate were significantly higher in the group with low LVEF than group without low LVEF (61.1% vs 21.6% p<0.001, 44.4% vs 11.6% p<0.001).

Conclusion

LVEF was significantly associated with MALE and all-cause death in patients with PAD.

P6182Combination of a new iterative reconstruction technique with low tube voltage and high tube current has important role of detection of late enhancement on 320 slice CT

Background

New iterative reconstruction tecniques, including Adaptive Iterative Dose Reduction 3D (AIDR 3D) and Forward Projected Model-based Iterative Reconstruction SoluTion (FIRST), have been recently available on new generation 320 slice CT, and they can provide high-quality CT images.

Purpose

The aim of this study was to evaluate the diagnostic performance of detection of abnormal late enhancement (LE) in left ventricular (LV) myocardium (LVM) using 320-slice CT with new iterative reconstruction techiniques, AIDR 3D (Figure A) and FIRST (Figure B).

Methods

A total of 100 patients who were suspected of having various myocardial diseases and underwent late phase acquisition both on cardiac CT and CMR within 3 months were analyzed. The first 50 consecutive patients (Group 1) underwent 320-slice CT with AIDR 3D, 120 Kv tube voltage, 519±71 mA tube current. The next 50 consecutive patients (Group 2) underwent 320-slice CT with FIRST, 80 or 100Kv tube voltage, 803±20 mA tube current. We compared diagnostic accuracy of CT for detection of LE in LVM against that of CMR (the gold standard) in between the 2 groups.

Results

On patient-by-patient analysis, sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and overall accuracy for detection of LE on CT vs CMR were 87, 95, 96, 82, and 90% in Group 1, and 97, 83, 91, 88, and 90% in Group 2. There were no significant difference of diagnostic accuracy on patient-by-patient analysis in between the 2 groups (Figure C). However, on a segment-by-segment analysis (using 17 American Heart Association LV segment model), these values for detection of LE on CT vs CMR were 60, 95, 73, 91, and 88% in Group 1, and 85, 95, 86, 95, and 93% in Group 2. Sensitivity, PPV, NPV and overall accuracy were significantly higher in Group 2 than in Group 1 (all P<0.01) (Figure D).

Conclusions

Diagnostic accuracy of detection of LE in LVM on CT combining low tube voltage and high tube current acquisition on a new generation 320-slice CT with FIRST was superior to 320-slice CT with AIDR 3D.

Acknowledgement/Funding

TSUCHIYA MEMORIAL MEDICAL FOUNDATION

Cartilage wear patterns in severe osteoarthritis of the trapeziometacarpal joint: a quantitative analysis

OBJECTIVE

The present quantitative study aimed to assess the three-dimensional (3-D) cartilage wear patterns of the first metacarpal and trapezium in the advanced stage of osteoarthritis (OA) and compare cartilage measurements with radiographic severity.

DESIGN

Using 19 cadaveric trapeziometacarpal (TMC) joints, 3-D cartilage surface models of the first metacarpal and trapezium were created with a laser scanner, and 3-D bone surface model counterparts were similarly created after dissolving the cartilage. These two models were superimposed, and the interval distance on the articular surface as the cartilage thickness was measured. All measurements were obtained in categorized anatomic regions on the articular surface of the respective bone, and we analyzed the 3-D wear patterns on the entire cartilage surface. Furthermore, we compared measurements of cartilage thickness with radiographic OA severity according to the Eaton grading system using Pearson correlation coefficients (r).

RESULTS

In the first metacarpal, the cartilage thickness declined volarly (the mean cartilage thickness of the volar region was 0.32 ± 0.16 mm, whereas that of the dorsal region was 0.53 ± 0.18 mm). Conversely, the cartilage evenly degenerated throughout the articular surface of the trapezium. Measurements of the categorized regions where cartilage thinning was remarkable exhibited statistical correlations with radiographic staging (r = -0.48 to -0.72).

CONCLUSIONS

Our findings indicate that cartilage wear patterns differ between the first metacarpal and trapezium in the late stage of OA. There is a need for further studies on cartilage degeneration leading to symptomatic OA in the TMC joint.

Femoral morphology asymmetry in hip dysplasia makes radiological leg length measurement inaccurate

AIMS

The aim of this study was to examine whether hips with unilateral osteoarthritis (OA) secondary to developmental dysplasia of the hip (DDH) have significant asymmetry in femoral length, and to determine potential related factors.

PATIENTS AND METHODS

We enrolled 90 patients (82 female, eight male) with DDH showing unilateral OA changes, and 43 healthy volunteers (26 female, 17 male) as controls. The mean age was 61.8 years (39 to 93) for the DDH groups, and 71.2 years (57 to 84) for the control group. Using a CT-based coordinate measurement system, we evaluated the following vertical distances: top of the greater trochanter to the knee centre (femoral length GT), most medial prominence of the lesser trochanter to the knee centre (femoral length LT), and top of the greater trochanter to the medial prominence of the lesser trochanter (intertrochanteric distance), along with assessments of femoral neck anteversion and neck shaft angle.

RESULTS

The percentages of hips with an absolute difference of > 5 mm in femoral GT and LT lengths were significantly larger in the DDH group (24% for both) compared with those of the control group (2% and 7%, respectively). The femoral length GT of the affected femur was significantly shorter in Crowe I and longer in Crowe IV than that of the unaffected side. The affected-to-unaffected difference of the intertrochanteric distance showed positive correlation with that of the femoral length GT in Crowe I and Crowe II/III, and negative correlation with that of the femoral length LT in the Crowe I and Crowe IV groups.

CONCLUSION

Hips with unilateral end-stage OA secondary to DDH show significant asymmetry in femoral length between both the greater and lesser trochanter and the knee compared with controls. The intertrochanteric distance was a morphological factor related to femoral-length asymmetry. When undertaking total hip arthroplasty (THA) in the presence of DDH, long leg radiographs or CT measurements should be used to assess true leg-length discrepancy. Cite this article: Bone Joint J 2019;101-B:297-302.

Abstract P1-08-12: Trends in incidence of bilateral breast cancer: A Population-based comparative study of the United States and Japan

Background: Previous studies demonstrated that the incidence rate of invasive contralateral breast cancer (CBC) was 5% within the first 10 years after the primary breast cancer (BC). However improving long-term breast cancer survivorship and advancements in diagnostic imaging have resulted in an increased detection of bilateral breast cancer (BBC), and trends of bilateral invasive and in situ breast cancer are not well established. The aim of this study was to assess national trends of BBC incidence of the United States (US) and Japan.

Methods: The Surveillance, Epidemiology, and End Results (SEER) database (1973-2014) and the clinical database of Breast Oncology Center of Cancer Institute Hospital in Tokyo, Japan (Ganken) database (1946-2015) were used to identify nSEER=11,771 and nGanken=1,499 women diagnosed with BBC, respectively. BBC was defined as invasive BC and/or ductal or lobular carcinoma in situ diagnosed in both breasts simultaneously or after primary breast cancer diagnosis. BBC was grouped into synchronous or metachronous BBC by the interval between first BC and contralateral BC; synchronous cases were defined as CBC diagnosed at the same time or within an interval of 1 year from primary BC diagnosis whereas metachronous cases were defined as a diagnosis occuring 1 year following the primary BC. We assessed trends of BBC incidence and characteristics of BBC cases between the two countries. To determine temporal trends in the incidence of BBC and proportion of the characteristics, we compared them using the Cochrane-Armitage test for trend.

Results: The rates of BBC have significantly increased in both countries (Table 1, 2) [1975: 2.6%; 2014: 7.5% in SEER (p&lt;0.001), 1946-1980: 3.3%; 2011-2015: 10.7% in Ganken (p&lt;0.001)]. The increase was identified in both synchronous and metachronous BBC. In SEER, 40% of synchronous BBC were found as in situ BC and about 15% of BBC presented as invasive lobular carcinoma. More recently, CBC was more likely to be diagnosed at early stages (in situ and local disease) than in previous years [1975: 65%; 2014: 85% in SEER (p&lt;0.001)]. The interval between first BC and contralateral BC have shortened, and CBC were more likely to be operated simultaneously in both countries [1985: 40%; 2014: 51% in SEER, 1946-1980: 24%; 2011-2015: 74% in Ganken].

[Table 1]Crude rates of BBC in all breast cancer in SEER 19751985199520052014All breast cancer941813618258766016471505BBC and rates (%)249 (2.6%)790(5.8%)1421(5.5%)3336(5.6%)5381(7.5%)Rates of synchronous BC2.1%2.8%2.3%2.6%3.5%Rates of metachronous BC0.5%3.0%3.2%3.0%4.0%BBC: Bilateral breast cancer

[Table 2]Crude rates of BBC in all breast cancer in Ganken 1946-19801981-19851991-19952001-20052011-2015All breast cancer47772162280637915241BBC and rates (%)157(3.3%)110(5.1%)188(6.7%)298(7.9%)559(10.7%)Rates of synchronous BC1.0%1.9%2.0%2.7%4.9%Rates of metachronous BC2.3%3.2%4.7%5.2%5.8%

Conclusion: In the modern era, the number of BBC cases have increased and are more likely to be found at an early stage. Further studies are needed to demonstrate the usefulness of early detection of CBC and to define the best means to tailor therapy for patients with bilateral disease.

Citation Format: Sakai T, Ozkurt E, Desantis S, Wong S, Rosenbaum L, Zheng H, Ohno S, Golshan M. Trends in incidence of bilateral breast cancer: A Population-based comparative study of the United States and Japan [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-08-12.

Ultrasound-guided coracohumeral ligament release

Long-term follow-up of patients with adhesive capsulitis (AC) reveals that approximately half of them suffer from a limited range of shoulder motion, particularly external and/or internal rotation. We report the surgical technique and short-term clinical outcomes of ultrasound-guided release of the thickened coracohumeral (CH) ligament in 8 patients (9 shoulders) with AC. Passive external rotation with the arm by the side significantly increased from an average of 18° preoperatively to 47° immediately after CH ligament release. VAS and ASES scores were improved at 3months follow-up in all 9 shoulders, and maintained at 6months follow-up in 6 shoulders. No procedure-related adverse events developed over the 6-month follow-up period. Ultrasound-guided release for thickened CH ligament is a reliable and effective minimally invasive surgery for persistent limited external rotation due to AC of the shoulder.

Dietary Protein Loading and the Oral Adsorbent AST-120 in the Progression of Chronic Renal Failure in the Rat

Excess protein intake enhances the progression of renal failure. The oral carbonaceous adsorbent, AST-120, was found experimentally and clinically to retard the progression of renal failure. This study was designed to determine whether deterioration of renal function by dietary protein loading can be prevented or mitigated by this oral adsorbent. Rats with uremia induced by partial renal infarction were fed a normal or high-protein diet for 70 days with or without AST-120, in which the inorganic phosphate content was adjusted to the same level. The survival rate deteriorated with the high dietary protein, but was improved from 30% to 100% with AST-120. Dietary protein loading reduced renal function, based on creatinine clearance. AST-120 improved renal function and renal histopathology not only in the normal diet group but in the high-protein group as well. The progression of renal failure induced by protein loading is thus shown to be prevented by oral AST-120. The mechanism for its action remains to be clarified.

Beta 2-Microglobulin Synthesis of Mononuclear Cells in Chronic Dialysis Patients

Beta 2 microglobulin (B2M) has been identified as a major component of amyloid deposits. This study was designed to determine whether changes occur in the synthesis of B2M in dialysis patients. Mononuclear cells (MNC) were isolated in peripheral blood from healthy volunteers, patients on hemodialysis (HD) and on continuous ambulatory peritoneal dialysis (CAPD). MNC were cultured in a medium of RPMI 1640 with or without interleukins IL-1, IL-2 or interferon INF-r. B2M in the cultured cells and supernatant was measured by enzyme immunoassay. IL-2 or INF-r stimulated B2M synthesis 'was significantly lower (25%) in patients on HD than in normal controls regardless of the type of dialysis membranes used, with no change in basal B2M synthesis. No differences were detected between healthy volunteers and CAPD patients. Preincubation of MNC with complement - activating or non-complement - activating membrane had no influence on B2M synthesis. The basal B2M synthesis of MNC significantly increased after a 4-hour HD regardless of the membranes used, and IL-2 and IFN-r stimulated synthesis were both essentially the same before and after HD. It was thus concluded that maximum capacity for B2M synthesis of MNC decreases in hemodialysis patients. This low responsiveness of MNC may be partially the cause for the reduction in cell-mediated immune response in HD patients.

Abstract P3-13-03: NEOS: A randomized, open label, phase 3 trial of adjuvant chemotherapy for postmenopausal breast cancer patients who responded to neoadjuvant letrozole: First report of long-term outcome and prognostic value of response to neoadjuvant endocrine therapy

Background: Whether adjuvant chemotherapy is required for patients (pts) with intermediate-risk endocrine-responsive postmenopausal breast cancer (BC) remains unknown. Sufficient data have not been available about the long-term prognosis of patients with neoadjuvant endocrine therapy (ET). NEOS is a randomized phase III study that assessed the long-term prognosis of estrogen receptor positive (ER+) primary breast cancer (PBC) pts who received neoadjuvant ET with/without adjuvant chemotherapy.

Methods: Postmenopausal BC pts with ER +/HER2 negative, T1c-2, clinically node negative, under 76 years old were enrolled at primary registration. Pts were treated by leterozole (LET) in weeks 24-28 after primary enrollment. Pts experienced progression (PD) during neoadjuvant phase were excluded at randomization and received any systemic therapy driven by investigators before or after surgery. The long-term prognosis was followed in all registered pts including PD pts. Response to neoadjuvant ET was evaluated as complete response (CR), partial response (PR) or stable disease (SD) using calipers, ultrasound and MRI (or CT) at the baseline and end of treatment before surgery. Pts who met eligibility criteria were randomized 1:1 to LET for 4.5-5 years after chemotherapy or LET alone for 4.5-5 years without chemotherapy after surgery. Pts excluded at second registration were treated any systemic therapies driven by investigators. The primary endpoint was disease-free survival (DFS) and secondary endpoints included overall survival (OS), clinical response rate in neoadjuvant phase, pathological response, and breast-conserving surgery rate. The randomization code have been blinded to the investigators.

Results: Between May 2008 and June 2013, 904 patients were enrolled at primary registration from 100 institutions in Japan (median follow-up: 4.0 years) and 24 pts were withdrawn during neoadjuvant phase. The median age was 63 years, T1c:37%, T2:63%, and PgR+:78%. Clinical response rates (CR, PR, SD and PD) were2% (16pts), 48% (421pts), 45% (400pts) and 5% (43pts), respectively and, in each response category, 0% (0/16), 5.5% (23/421), 7.8% (31/400), and 20.9% (9/43) experienced DFS events. DFS in PD pts to neoadjuvant ET were statistically significantly worse than CR, PR, SD pts (p&lt;0.0001, hazard ratio 4.7 (95% CI:2.3-9.5). The prognosis after surgery in 669 randomized pts was good regardless with/without chemotherapy, forty four pts (6.6%) experienced DFS events after surgery. The predictive markers of PD for neoadjuvant ET were yet unclear among evaluated clinical factors.

Conclusion: This is the first report of DFS in the largest neoadjuvant ET trial (NEOS). The DFS of postmenopausal, ER+/HER2-, PBC pts excluding PD pts to neoadjuvant ET is highly good regardless with/without chemotherapy. Neoadjuvant ET with utilization of PD response as a prognostic marker can be considered as a standard treatment option for these patients. Clinical trial information: UMIN000001090.

Citation Format: Iwata H, Masuda N, Fujisawa T, Toyama T, Ohtani S, Yamamoto Y, Kashiwaba M, Taira N, Sakai T, Hasegawa Y, Nakamura R, Akabane H, Shibahara Y, Sasano H, Yamaguchi T, Ohashi Y. NEOS: A randomized, open label, phase 3 trial of adjuvant chemotherapy for postmenopausal breast cancer patients who responded to neoadjuvant letrozole: First report of long-term outcome and prognostic value of response to neoadjuvant endocrine therapy [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 P3-13-03.

Abstract PD5-03: TransNEOS: Validation of the oncotype DX recurrence score (RS) testing core needle biopsy samples from NEOS as predictor of clinical response to neoadjuvant endocrine therapy for postmenopausal estrogen receptor positive (ER+), HER2 negative (HER2-) breast cancer patients

Background: Neoadjuvant therapy for locally advanced breast cancer has the potential to improve surgical therapeutic outcomes without sacrificing the survival advantages of adjuvant therapy. However, determining whether ER+ patients (pts) will respond to neoadjuvant (NA) chemotherapy (CT) or hormone therapy (HT) can be difficult. Not all ER+ pts respond to NACT, while response to NAHT can vary across ER+ pts. Thus, the ability to select pts more likely to benefit from NAHT would represent progress in clinical management of breast cancer. NEOS is a randomized phase III study assessinglong-term prognosis of ER+ primary breast cancer with/without adjuvant CT following NAHT (UMIN 000001090, http://www.umin.ac.jp/). We used archived core biopsy tumor samples from the NEOS study to validate the RS result as a predictor of clinical response and its association with successful breast conserving surgery (BCS) in pts treated with 6 months of NAHT.

Methods: NEOS enrolled 904 postmenopausal pts with ER+, HER2-, clinically node negative (cN0) breast cancer to evaluate whether adjuvant CT was necessary for pts who responded to NAHT. In this current study, we enrolled pts with tumors ≥2cm from the NEOS study. Biopsy samples of 333 pts were assessed for the Oncotype DX assay. Response to NAHT was recorded as complete/partial response (CR/PR), or stable/progressive disease (SD/PD).

Primary endpoint of this study was to evaluate clinical response (CR/PR) to NA letrozole between pts with low (&lt;18) and high (≥31) RS result. Secondary endpoints include evaluating the relationships between clinical response and continuous RS results, and other covariates including age, tumor size, grade, Ki67 by IHC, ER and PR single gene scores, and ER and proliferation gene group scores by RT-PCR.

Results: The analysis included 294 pts with median age of 63 yrs, median tumor size of 25mm, and 66% were nuclear grade 1. 156 (53.0%), 83 (28.6%) and 54(18.4%) cases were low, intermediate, and high RS groups by Oncotype DX, respectively. Six (2%), 126 (42.8%), 149 (50.3%), 13 (4.4%) cases experienced CR, PR, SD, PD as clinical response, respectively, similar to that of all NEOS pts. Clinical response rate was 54%, 42% and 22% in low, intermediate, and high RS groups, respectively. The proportion of pts with clinical response was significantly higher in the low RS group vs the high RS group (p&lt;0.001). In univariate analyses, continuous RS was significantly associated with clinical response (p&lt;0.001), along with ER (p=.02), PR (p&lt;0.001), and ER gene group score (p&lt;0.001). Other covariates were not associated with clinical response.

Conclusion: The Oncotype DX RS test in core biopsy samples is validated as a predictive assay for clinical response of NAHT in postmenopausal, ER+/HER2-, cN0, primary early breast cancer pts. Further results on the association of RS results with BCS outcomes following NAHT will be presented. These results when combined with previously published data on RS in NACT studies help guide pts with ER+, HER2- breast cancer with NAHT vs NACT treatment options to maximize clinical response.

Citation Format: Yamamoto Y, Iwata H, Masuda N, Fujisawa T, Toyama T, Kashiwaba M, Ohtani S, Taira N, Sakai T, Hasegawa Y, Nakamura R, Akabane H, Shibahara Y, Sasano H, Yamaguchi T, Sakamaki K, Chao C, McCullough D, Sugiyama N, Ohashi Y. TransNEOS: Validation of the oncotype DX recurrence score (RS) testing core needle biopsy samples from NEOS as predictor of clinical response to neoadjuvant endocrine therapy for postmenopausal estrogen receptor positive (ER+), HER2 negative (HER2-) breast cancer patients [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 PD5-03.

Study of termination of postprandial gastric contractions in humans, dogs and Suncus murinus: role of motilin- and ghrelin-induced strong contraction

AIM

Stomach contractions show two types of specific patterns in many species, that is migrating motor contraction (MMC) and postprandial contractions (PPCs), in the fasting and fed states respectively. We found gastric PPCs terminated with migrating strong contractions in humans, dogs and suncus. In this study, we reveal the detailed characteristics and physiological implications of these strong contractions of PPC.

METHODS

Human, suncus and canine gastric contractions were recorded with a motility-monitoring ingestible capsule and a strain-gauge force transducer. The response of motilin and ghrelin and its receptor antagonist on the contractions were studied by using free-moving suncus.

RESULTS

Strong gastric contractions were observed at the end of a PPC in human, dog and suncus models, and we tentatively designated this contraction to be a postprandial giant contraction (PPGC). In the suncus, the PPGC showed the same property as those of a phase III contraction of MMC (PIII-MMC) in the duration, motility index and response to motilin or ghrelin antagonist administration. Ghrelin antagonist administration in the latter half of the PPC (LH-PPC) attenuated gastric contraction prolonged the duration of occurrence of PPGC, as found in PII-MMC.

CONCLUSION

It is thought that the first half of the PPC changed to PII-MMC and then terminated with PIII-MMC, suggesting that PPC consists of a digestive phase (the first half of the PPC) and a discharge phase (LH-PPC) and that LH-PPC is coincident with MMC. In this study, we propose a new approach for the understanding of postprandial contractions.

Clonal structure in Ichthyobacterium seriolicida, the causative agent of bacterial haemolytic jaundice in yellowtail, Seriola quinqueradiata, inferred from molecular epidemiological analysis

Bacterial haemolytic jaundice caused by Ichthyobacterium seriolicida has been responsible for mortality in farmed yellowtail, Seriola quinqueradiata, in western Japan since the 1980s. In this study, polymorphic analysis of I. seriolicida was performed using three molecular methods: amplified fragment length polymorphism (AFLP) analysis, multilocus sequence typing (MLST) and multiple-locus variable-number tandem repeat analysis (MLVA). Twenty-eight isolates were analysed using AFLP, while 31 isolates were examined by MLST and MLVA. No polymorphisms were identified by AFLP analysis using EcoRI and MseI, or by MLST of internal fragments of eight housekeeping genes. However, MLVA revealed variation in repeat numbers of three elements, allowing separation of the isolates into 16 sequence types. The unweighted pair group method using arithmetic averages cluster analysis of the MLVA data identified four major clusters, and all isolates belonged to clonal complexes. It is likely that I. seriolicida populations share a common ancestor, which may be a recently introduced strain.