Automated heart segmentation using a convolutional neural network accelerates 3D model creation for cardiac surgery

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Japan Organization of Occupational Health and Safety

onbehalf

J3D

Introduction

Improvements in cardiovascular imaging have contributed to the accurate diagnosis and treatment of cardiovascular diseases. In recent years, we can find a new demand from surgical departments, i.e., 3D heart models of patients for preoperative simulations. However, a 3D surgical model needs a detailed segmentation of heart structures from clinical images because these details are essential for achieving accurate polygon data of an exact 3D model. Thus, in most cases, manual segmentation is required for complicated heart shapes such as the chamber wall, valves, and papillary muscles, which causes a prolonged duration time.

Purpose

We aim to achieve an automated heart segmentation using a convolutional neural network (CNN) trained using deep learning techniques for the rapid creation of 3D surgical heart models of individual patients.

Methods

We constructed our original CNN program based on the latest artificial intelligence techniques and trained it to extract shapes of the heart from cardiac computed tomography (CT) images. The training data was 361 slices selected from CT scans of 10 patients. We used data augmentation to increase the amount and diversity of the data into 24,052 slices. The training result with the best Intersection over Union (IoU), one of the evaluation metrics used in deep learning, was saved. Finally, we used the best-trained CNN to construct 3D polygon data of two surgical cases of hypertrophic obstructive cardiomyopathy (HOCM) for preoperative assessments.

Results

The IoU attained 0.85 after deep learning. The time required to complete the 3D polygon data for the first HOCM case was 5 minutes for segmentation by the trained CNN and 3 hours for data correction by a human operator. Similarly, the time required for the second case was 5 minutes for segmentation without manual correction. We had to correct the segmentation for the first case because we needed an exact 3D model for the preoperative assessment (Fig. 1). According to our records of the other eight 3D heart models in the lab, the work for a 3D polygon shape from CT images needs a median 30 hours (quartiles 23-50 hours) when the procedure is fully manual and non-continuous with breaks in between.

Conclusion

The CNN-based segmentation aided the constructing heart shapes from cardiac CT images of preoperative patients. Although the performance, reaching IoU of 0.85, was insufficient for fully automatic segmentation, the methodology can shorten the process duration from several hours to several minutes for detailed segmentation of heart structures.

We previously applied the CNN-based segmentation to the aorta, aortic stenosis valves, and atheromatous plaque in clinical images, demonstrating adequate segmentation performance. The proposed methodology can be applied as a fundamental technology of cardiovascular imaging for obtaining the actual structures of a target object as 3D coordinate values or a 3D model within a reasonable duration time.

Abstract Figure 1

IL-15 is a biomarker involved in the development of rapidly progressive interstitial lung disease complicated with polymyositis/dermatomyositis

BACKGROUND

Polymyositis/dermatomyositis (PM/DM) is an autoimmune disease that is sometimes complicated with rapidly progressive interstitial lung disease (RPILD). However, serum and lung biomarkers that can predict RPILD development remain unclear.

OBJECTIVES

To determine potential serum and lung biomarkers that can predict RPILD development in patients with PM/DM-ILD.

METHODS

In total, 49 patients with PM/DM-ILD were enrolled. We measured the serum levels of 41 cytokines/chemokines, ferritin and anti-MDA5 antibody, compared them between the RPILD (n = 23) and non-RPILD (n = 26) groups, and ranked them by their importance through random forest analysis. To distinguish the two groups, we determined biomarker combinations by logistic regression analysis. We also measured the bronchoalveolar lavage fluid (BALF) levels of 41 cytokines/chemokines. Using immunohistochemistry, we examined IL-15 expression in lung tissues. The IL-15 production was also investigated using A549 and BEAS-2B cells.

RESULTS

The RPILD group had significantly higher IL-15, IL-1RA, IL-6, CXCL10, VCAM-1, anti-MDA5 antibody and ferritin serum levels than the non-RPILD group, but it had a significantly low CCL22 level. Meanwhile, anti-MDA5 antibody, IL-15, CXCL8, CCL22, IL-1RA and ferritin were the best combination to distinguish the two groups. IL-15 and CCL22 were also predictive marker for RPILD development in anti-MDA5 antibody-positive patients. Additionally, the RPILD group had significantly high IL-15 levels in BALF. The lung tissues expressed IL-15, which increased after cytokine stimulation in the A549 cells.

CONCLUSION

This study identified a combination of biomarkers predicting PM/DM-RPILD progression, and IL-15 is an important cytokine for predicting RPILD development and reflecting ILD severity.

Factor structure of the professional quality of life scale among direct support professionals: factorial validity and scale reliability

BACKGROUND

Direct support professionals (DSPs) support people with intellectual and developmental disabilities in activities of daily living. DSPs may experience both contentment and struggles with their work. As agencies grapple with their recruitment and retention, understanding DSPs' holistic work experience is important. The Professional Quality of Life (ProQOL) scale assesses multiple domains of work experiences (i.e. compassion satisfaction, burnout and secondary traumatic stress). Despite extensive use across helping professions, the ProQOL is largely absent from DSP research.

METHOD

This study examined the factor structure of the ProQOL with DSPs. Using secondary data from 495 DSPs, confirmatory factor analysis was conducted to determine if the original three-factor structure holds for this population.

RESULTS

We confirmed the factorial validity of the ProQOL with the three-factor solution. In the validation process, some modifications were suggested to the model, which also improved the scale reliability.

CONCLUSIONS

The current study provides initial evidence of the factorial validity of the ProQOL when used with DSPs, as well as recommendations for subsequent improvements and future research.

FRI0535 NEWLY DETECTED HYPERTHYROIDISM WITH THERAPEUTIC INDICATIONS IN RHEUMATIC DISEASE PATIENTS AND HEALTHY CONTROLS IN JAPAN: A RETROSPECTIVE COHORT STUDY

Background:

Thyroid disorders are known as common comorbidities of rheumatic diseases(RD) [1]. However, data regarding prevalence of hyperthyroidism with treatment indication in RD patients are limited.

Objectives:

This study aims to reveal and compare the frequency of newly developed hyperthyroidism with treatment indication between RD patients and healthy controls (HC), and identify risk factors to identify patients whose thyroid function should be followed up carefully.

Methods:

We retrospectively reviewed charts of RD patients and HC who had thyroid stimulating hormone (TSH) measured at least once between 2004 and 2018 from immuno-rheumatology center and preventive medicine center in St. Luke’s International Hospital, Japan. We compared frequency of hyperthyroidism requiring treatment (TSH ≦ 0.1μU/mL or for which physicians started treatment) with Kaplan-Meier curve and log rank test. Cox regression multivariate analysis was performed to reveal risk factors for the new onset of hyperthyroidism with treatment indication in participants without treatment-indicated hyperthyroidism at initial assessments.

Results:

Overall, 2307 RD patients and 78251 HC were included. Newly detected hyperthyroidism with treatment indication were significantly more frequent in RD patients at initial assessment (1.3% vs 0.5 %, p < 0.001) and in total (2.9% vs 1.7%, p<0.001) (Table 1, Figure 1). Cox regression multivariate analysis revealed systemic lupus erythematosis (SLE), polymyositis dermatomyositis (PMDM), mixed connective tissue disease (MCTD) as significant risk factors of new developments of hyperthyroidism during follow up after adjusting confounders. (Table 2)

Table 1.

Patients characteristics and results of hyperthyroidism

Rheumatic Disease (n = 2307)Control (n = 78251)p.valueAge(yr)53.7 (16.2)46.1 (11.9)<0.001Female (%)1826 (79.2)38632 (49.4)<0.001 Rheumatoid arthritis (%)1091 (47.3)-NA Spondyloarthritis161 (7.0)-NA ANA associated disease (%)944 (40.9)-NA  SLE(%)363 (15.7)-NA  SS (%)396 (17.2)-NA  PMDM(%)104 (4.5)-NA  SSc (%)222 (9.6)-NA  MCTD (%)43 (1.9)-NA Vasculitis (%)202 (8.8)-NA Others (%)244 (10.6)-NATimes of TSH measurement2.0 [1.0, 5.0]5.0 [3.0, 9.0]<0.001Follow up of TSH (days)258.00 [0, 1315]1992 [958, 3632]<0.001Baseline TSH (μU/mL)2.28 (3.21)2.15 (4.07)0.137 ≦0.45 μU/mL (%)86 (3.7)1371 (1.8)<0.001 ≦0.1 μU/mL (%)29 (1.3)389 (0.5)<0.001Baseline FreeT4 (μU/mL)1.16 (0.24)1.30 (0.20)<0.001≧1.65 μU/mL (%)17 (0.8)2355 (3.0)<0.001TSH level in follow up ≦0.45 μU/mL (%)231 (0.0)3926 (5.0)<0.001 ≦0.1 μU/mL (%)84 (3.6)1388 (1.8)<0.001Newly detected hyperthyroidism with treatment indication (%)68 (2.9)1350 (1.7)<0.001 At initial assessment (%)29 (1.3)389 (0.5)<0.001 In follow up (%)39 (1.6)961 (1.2)<0.001Treatment for hyperthyroidism (%)21 (0.9)325 (0.4)0.002Figure 1.

Hyperthyroidism with treatment indication in rheumatic patients and control

Table 2.

Risk factors for newly detected hyperthyroidism with treatment indication

Adjusted HRp valueAge0.99 (0.98-0.99)< 0.001Female2.68 (2.31-3.12)< 0.001BMI1.04 (1.02-1.06)< 0.001Baseline TSH ≦ 0.455.71 (4.47-7.30)< 0.001Baseline Free T4 ≧ 1.651.16 (0.79-1.69)0.45Rheumatoid arthritis1.05 (0.50-2.21)0.90ANA associated diseases-- SLE2.29 (1.11-4.71)0.025 SS1.91 (0.91-4.01)0.089 PMDM12.90 (5.50-30.22)< 0.001 SSc0.67 (0.18-2.43)0.541 MCTD8.02 (2.62-24.51)< 0.001Vasculitis1.44 (0.35-5.92)0.610Spondyloarthritis3.04 (0.74-12.52)0.120Others1.98 (0.67-5.81)0.214

Conclusion:

Hyperthyroidism with therapeutic indications are considerably more frequent in RD patients (particularly with SLE, PMDM and MCTD) both at initial assessment and during follow up. We recommend routine screening at initial assessment and careful follow up of thyroid function test in those patients.

References:

[1] Rev Bras Rheumatol 2012;52(3):417-430

Disclosure of Interests:

None declared

AB0533 ANTI-NEUTROPHIL CYTOPLASMIC ANTIBODY (ANCA) IN GENERAL POPULATION WITHOUT ANCA ASSOCIATED VASCULITIS

Background:

Currently it is hypothesized that many systemic autoimmune diseases occur due to environmental risk factors in addition to genetic risk factors. Anti-Neutrophil Cytoplasmic Antibody (ANCA) is mainly associated with three systemic autoimmune disease including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA). It is known that ANCA can be positive before clinical symptoms in patients with known diagnosis of GPA and ANCA titers rise before clinical manifestations appear. However, prevalence of ANCA among general population is not well known. It has not been described as well how many of people with positive ANCA eventually develop clinical manifestations of ANCA associated Vasculitis.

Objectives:

This study aims to estimate prevalence of ANCA in general population without ANCA associated Vasculitis. It also describes natural disease course of people with positive ANCA without ANCA associated Vasculitis. Risk factors for positive ANCA are also analyzed.

Methods:

This is a single center retrospective study at Center for Preventive Medicine of St. Luke’s International Hospital in Tokyo. ANCA was checked among the patients who wished to between 2018 and 2019. St. Luke’s Health Check-up Database (SLHCD) was utilized to collect the data. The patients whose serum was measured for ANCA were identified. The data for basic demographics, social habits, dietary habits and laboratory data were extracted. The charts of the patients with positive ANCA were reviewed.

Results:

Sera of total 1204 people were checked for ANCA. Of these 1204 people, 587 (48.8%) are male and the mean age was 55.8 years (32.6 to 79). There were total 11 patients with positive ANCA. Myeloperoxidase ANCA (MPO-ANCA) was positive for 3 patients and proteinase 3 ANCA (PR3-ANCA) was positive for 8 patients. Of these 11 patients, 5 were male (45.5%) and the mean age was 54.6 years. Two patients had history of autoimmune disease (primary biliary cirrhosis and ulcerative colitis). Five patients were evaluated by rheumatologists with the median follow-up period of 274 days. None of them developed clinical signs and symptoms of ANCA associated Vasculitis. Four out of five patients had ANCA checked later, two of which turned negative. The prevalence of ANCA in this cohort was 0.9% (95% confidence interval [95% CI]: 0.5% to 1.6%). Univariate analysis was performed to identify risk factors of positive ANCA. The variables analyzed include age, gender, body mass index (BMI), smoking habits, alcohol intake, dietary habits (fruits, fish, red meat), hypertension, dyslipidemia, and laboratory data. None of these variables demonstrated statistically significant differences except for positive rheumatoid factor (ANCA positive group: 33 % vs ANCA negative group: 9.1%, p value = 0.044).

Conclusion:

The prevalence of ANCA in this cohort was 0.9% (95% CI: 0.5% to 1.6%). None of them who had a follow-up developed ANCA associated Vasculitis during the follow-up period. Longer follow-up and more patients are necessary to determine natural course of people with positive ANCA.

Disclosure of Interests:

None declared

SAT0525 EFFICACY AND SAFETY OF MZR FOR IgG4-RELATED DISEASE

Background:

IgG4-Related Disease (IgG4RD) is known to cause multiple organ lesions with infiltration of IgG4-positive plasma cells, and patients often have relapses with tapering treatments despite an initial good response to glucocorticoids therapy. Mizoribine (MZR) is an immunosuppressant working as an inhibitor of purine synthesis, which mechanism of action is similar to mycophenolate mofetil. Data regarding the efficacy and safety of MZR on IgG4RD is limited although some previous case reports1showed effectiveness for IgG4RD.

Objectives:

This study aims to assess the efficacy and safety of MZR in patients with IgG4RD.

Methods:

We retrospectively reviewed charts of IgG4RD patients who used MZR between January 2004 and December 2019 at Immuno-Rheumatology Center in St. Luke’s International Hospital, Tokyo, Japan. We investigated basic demographics, involved organs, results of blood tests including IgG and IgG4 titer, and medications used including glucocorticoid and other immunosuppressants (IS). We followed IgG4 titer, dose of glucocorticoid, flare of disease and retention of MZR at the beginning, 6 and 12months after starting MZR. We compared changes in PSL (prednisolone) doses and IgG4 titers over time using Friedman test with Bonferroni correction. We also checked adverse events during follow up.

Results:

Twenty-two patients with IgG4RD who used MZR were included. Median age was 62 years old, and 15 (68.2%) patients are male. Lacrimal and salivary glands, pancreatitis and retroperitoneal fibrosis were common lesions. All patients were initially treated with glucocorticoids. Flare was observed in 5 (22.7 %) patients before initiation of MZR. The number of patients who continued MZR without flare are 19 (86.4 %) at 6 months, and 14 (73.7 %) at 12 months. IgG4 titer significantly declined at 6 and 12 months from baseline although significant consecutive decrease in PSL dose (Figure 1, 2). Liver dysfunctions are commonest adverse events (n=16, 72.7%) but mild (grade1; n=15, 68.2%) and most cases are apparently due to other reasons. Serious infection (SI) occurred in 3 (13.6%) patients in total follow up, however no SI were observed during 1 year after MZR treatment.

Conclusion:

MZR can be safely used in patients of IgG4RD with high retention rate, and seemed to have steroid-sparing effect. Prospective comparative studies are needed.

References:

[1]Nanke Y, Kobashigawa T, Yago T, Kamatani N, Kotake S. A case of Mikulicz’s disease, IgG4-related plasmacytic syndrome, successfully treated by corticosteroid and mizoribine, and then by mizoribine alone. Intern Med 49: 1449-1453, 2010.

Table 1.

Patient characteristics

    Table 2.

Disease and treatment status before and after initiation of MZR

    Figure 1.

Serum IgG4 level changes

Figure 2.

Changes in the PSL dose over time

Disclosure of Interests:

None declared

AB0198 SMOKING AND POSITIVITY OF RHEUMATOID FACTOR AND ANTI-CYCLIC CITRULLINATED PEPTIDE ANTIBODY IN THE GENERAL POPULATION

Background:

It is well known that rheumatoid arthritis (RA) occurs due to environmental risk factors in addition to genetic risk factors. Rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (ACPA) are strongly associated with RA, and these biomarkers could turn to be positive before development of clinical symptoms. While smoking, particularly Brinkman index (BI) is well known as a risk factor for RA and ACPA positivity, it is still unclear whether smoking intensity or smoking duration contribute more to positive RF and ACPA.

Objectives:

This study aims to evaluate risk factors for RF and ACPA positivity in the general population. It also describes whether smoking intensity, duration, and BI are significant.

Methods:

This is a cross-sectional, observational, single center study. We reviewed the baseline characteristics of the general population who checked RF and ACPA at Preventive Medicine Center in St. Luke’s International Hospital, Tokyo, Japan from January 2004 to December 2018.

The data for basic demographics, dietary habit, smoking intensity, smoking duration, BI, and blood tests including RF and ACPA were extracted. The data was analyzed statistically.

Results:

A total of 127472 people who checked RF are included. Of these 127472 people, 64504 (50.6%) are male and the mean age was 44.9 years. RF was positive in 11477 people (9.0%). Among these, 1667 (1.2%) were checked for ACPA, and 21 people (1.3%) had positive ACPA. None of variables demonstrated significant association with RF positivity. In contrast, BI and smoking duration was significantly associated with an increased risk of ACPA positivity (13.3 years vs 7.49 years, p value = 0.023), although the number of cigarettes smoked was not. The smoking duration for 10 years or more was associated with an increased risk of ACPA positivity even after adjusted for age and sex (adjusted hazard ratio: 2.47 [95% confidence interval: 1.04-5.87]; p=0.04).

Conclusion:

In this study, no significant risk factor for positive RF was found. Even smoking was not associated with RF positivity. On the other hand, smoking duration, not smoking intensity was significantly associated with an increased risk of ACPA positivity.

References:

[1]Verpoort KN. Association of smoking with the constitution of the anti-cyclic citrullinated peptide response in the absence of HLA-DRB1 shared epitope alleles. Arthritis Rheum 2007;56:29138.

Table 1.

Patient characteristics with RF and ACPA positivity

RF positive (n=11477)RF negative (n=115995)p valueACPA positive (n=21)ACPA negative (n=1646)p valueAge44.86 (12.32)44.94 (12.47)0.5437.90 (9.07)45.26 (12.58)0.008Male (%)5659 (49.3)57309 (49.4)0.84511 (52.4)834 (50.7)1Body Mass Index22.33 (3.38)22.35 (3.40)0.52121.64 (3.28)22.34 (3.37)0.346Smoker, total (%)4509 (39.3)45738 (39.4)0.77212 (57.1)642 (39.0)0.115Current smoker (%)1959 (17.1)20483 (17.7)0.1148 (38.1)277 (16.8)0.017Previous smoker (%)2550 (22.2)25255 (21.8)0.2714 (19.0)365 (22.2)1Brinkman index144.8 (299.3)145.2 (313.8)0.897280.9 (409.7)145.3 (300.3)0.041Number of cigarettes (/day)17.7 (18.5)17.4 (13.3)0.16619.8 (12.0)17.4 (12.1)0.511Smoking Duration (years)7.43 (11.68)7.45 (11.66)0.85113.33 (14.11)7.49 (11.68)0.023Alcohol Drinker (%)6972 (60.7)70010 (60.4)0.41810 (47.6)1005 (61.1)0.261Alcohol Intake (g/day)13.67 (21.88)13.58 (21.32)0.67616.70 (26.89)14.06 (22.16)0.59Exercise ≧3 times/week (%)2792 (24.3)28293 (24.4)0.8825 (23.8)402 (24.4)1White blood cell (103/μL)5.32 (1.46)5.35 (1.50)0.135.59 (2.05)5.37 (1.54)0.52Hemoglobin (g/dL)13.82 (1.44)13.82 (1.45)0.75314.12 (1.03)13.83 (1.43)0.36Creatinine (mg/dL)0.73 (0.20)0.73 (0.25)0.1940.76 (0.16)0.73 (0.18)0.586AST (U/L)21.89 (9.39)21.93 (11.65)0.78220.95 (6.02)21.68 (8.29)0.69LDL cholesterol (mg/dL)115.41 (30.90)115.48 (30.77)0.815112.62 (33.26)115.36 (31.03)0.688Triglyceride (mg/dL)97.63 (78.46)97.70 (80.36)0.929100.57 (63.40)97.85 (78.37)0.874Uric Acid (mg/dL)5.32 (1.42)5.33 (1.42)0.6235.76 (1.34)5.34 (1.42)0.172

Disclosure of Interests:

None declared

Complement profile in microscopic polyangiitis and granulomatosis with polyangiitis: analysis using sera from a nationwide prospective cohort study

OBJECTIVE

The complement cascade, especially the alternative pathway of complement, has been shown in basic research to be associated with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). We aimed to elucidate relationships between serum complement components and clinical characteristics in AAV.

METHOD

In a nationwide prospective cohort study (RemIT-JAV-RPGN), we measured the serum levels of C1q, C2, C3, C3b/iC3b, C4, C4b, C5, C5a, C9, factor B, factor D, factor H, factor I, mannose-binding lectin, and properdin in 52 patients with microscopic polyangiitis (MPA) and 39 patients with granulomatosis with polyangiitis (GPA).

RESULTS

The properdin level of MPA and GPA was significantly lower than that of healthy donors. The properdin level was negatively correlated with the Birmingham Vasculitis Activity Score (BVAS) (ρ = -0.2148, p = 0.0409). The factor D level at 6 months was significantly positively correlated with the Vasculitis Damage Index (VDI) at 6, 12, and 24 months (ρ = 0.4207, 0.4132, and 0.3115, respectively). Patients with a higher ratio of C5a to C5 had higher neutrophil percentage and serum immunoglobulin G levels, and significantly lower creatinine levels. Cluster analysis divided the MPA and GPA patients into three subgroups. A principal component (PC) analysis aggregated 15 types of complements into alternative pathway-related PC 1 and complement classical pathway and common pathway-related PC 2.

CONCLUSIONS

The serum levels of properdin and factor D were correlated with the BVAS and the VDI in MPA and GPA, respectively. Our analyses suggested the pathological heterogeneity of MPA and GPA from the aspect of complement components.

Complete renal response at 12 months after induction therapy is associated with renal relapse-free rate in lupus nephritis: a single-center, retrospective cohort study

Background

Lupus nephritis (LN) is a major risk factor for overall morbidity and mortality in systemic lupus erythematosus (SLE).

Methods

We retrospectively analyzed cases of proliferative and membranous LN patients who underwent a renal biopsy at our hospital in 1993–2016. We analyzed the association between complete renal response (CR) rates at 12 months after induction therapy and predictive factors for CR and their association with renal flares.

Results

Of the 95 cases analyzed, we were able to track the therapeutic responses of 81 patients at 12 months after their induction therapy. The median follow-up duration after renal biopsy was 51 months (interquartile range: 16.5–154.5 months). The Cox proportional hazards model showed that, compared to not attaining CR at 12 months, the attainment of CR at 12 months was correlated with being free from renal flares. The multivariate logistic analysis revealed that the predictive factors for CR at 12 months were the anti-La/SSB antibodies (U/ml) (odds ratio (OR) 1.22, 95% confidence interval (CI) 1.01–1.63, p = 0.0220), blood urea nitrogen (BUN) (OR 0.68, 95% CI 0.44–0.90, p = 0.00048) and serum β2 microglobulin (MG) (OR 0.26, 95% CI 0.06–0.74, p = 0.00098) levels.

Conclusions

Among LN patients, being free from renal flares was associated with attaining CR at 12 months after induction therapy. Anti-La/SSB antibodies were a positive predictive factor, and BUN and serum β2MG levels were negative predictive factors of CR at 12 months.

Factors predictive of long-term mortality in lupus nephritis: a multicenter retrospective study of a Japanese cohort

Background

Lupus nephritis (LN) is a major determinant of mortality in systemic lupus erythematosus (SLE). Here we evaluated the association between complete renal response (CR) and mortality in LN.

Methods

We retrospectively analyzed the cases of 172 of 201 patients with LN for whom data on the therapeutic response at 6 and 12 months after induction therapy were available. The patients underwent a renal biopsy at Nagasaki University Hospital and community hospitals in Nagasaki between the years 1990 and 2016. We determined the CR rates at 6 and 12 months after induction therapy initiation and evaluated the predictive factors for CR and their relationship with mortality. We performed univariate and multivariable competing risks regression analyses to determine the factors predictive of CR. The patients' survival data were analyzed by the Kaplan–Meier method with a log-rank test.

Results

The median follow-up duration after renal biopsy was 120 months (interquartile range: 60.3–191.8 months). The 5-, 10-, 15- and 20-year survival rates of our cohort were 99.3, 94.6, 92.0 and 85.4%, respectively. During follow-up, nine patients (5.2%) died from cardiovascular events, infection, malignancy and other causes. The multivariate analysis revealed that the following factors were predictive of CR. At 6 months: male gender (odds ratio (OR) 0.23, 95% confidence interval (CI) 0.08–0.65, p = 0.0028), proteinuria (g/gCr) (OR 0.83, 95% CI 0.71–0.97, p = 0.0098) and index of activity (0–24) (OR 0.84, 95% CI 0.71–0.99, p = 0.0382). At 12 months: male gender (OR 0.25, 95% CI 0.09–0.67, p = 0.0043) and index of activity (0–24) (OR 0.82, 95% CI 0.69–0.98, p = 0.0236). The Kaplan–Meier analysis showed that compared to not achieving CR at 12 months, achieving CR at 12 months was significantly correlated with the survival rate (OR 0.18, 95% CI 0.04–0.92, p = 0.0339).

Conclusions

Our results suggest that the survival rate of patients with LN is associated with the achievement of CR at 12 months after induction therapy, and that male gender and a higher index of activity (0–24) are the common predictive factors for failure to achieve CR at 6 and 12 months.

Differential Cross Section and Photon-Beam Asymmetry for the γ[over →]p → π^{-}Δ^{++}(1232) Reaction at Forward π^{-} Angles for E_{γ}=1.5-2.95 GeV

Differential cross sections and photon-beam asymmetries for the γ[over →]p→π^{-}Δ^{++}(1232) reaction have been measured for 0.7<cosθ_{π}^{c.m.}<1 and E_{γ}=1.5-2.95  GeV at SPring-8/LEPS. The first-ever high statistics cross-section data are obtained in this kinematical region, and the asymmetry data for 1.5<E_{γ}(GeV)<2.8 are obtained for the first time. This reaction has a unique feature for studying the production mechanisms of a pure uu[over ¯] quark pair in the final state from the proton. Although there is no distinct peak structure in the cross sections, a non-negligible excess over the theoretical predictions is observed at E_{γ}=1.5-1.8  GeV. The asymmetries are found to be negative in most of the present kinematical regions, suggesting the dominance of π exchange in the t channel. The negative asymmetries at forward meson production angles are different from the asymmetries previously measured for the photoproduction reactions producing a dd[over ¯] or an ss[over ¯] quark pair in the final state. Advanced theoretical models introducing nucleon resonances and additional unnatural-parity exchanges are needed to reproduce the present data.

Useful Predictive Factors for Bacteremia among Outpatients with Pyelonephritis

Objective The aim of this study was to identify predictive factors for bacteremia conveniently and quickly among outpatients diagnosed with pyelonephritis. Patients All patients who were diagnosed with pyelonephritis at the outpatient clinic in the Department of General Medicine of Juntendo University Hospital from April 1, 2008, to June 30, 2015, were enrolled. Patients from whom blood cultures had not been taken were excluded. Methods Clinical information was extracted from medical charts. Factors potentially predictive of bacteremia were analyzed using a t-test and Fisher's exact test, followed by a multivariable logistic regression model analysis. Results Blood cultures were drawn from 116 patients, and 25 (22%) presented with bacteremia. A multivariate analysis with the age, chills, platelet count and urine nitrite test results revealed that older age, positive urinary nitrite test results and chills tended to be associated with bacteremia, respectively. [older age: unit odds ratio (OR) 1.02, p=0.052, 95% confidence interval (CI) 1.00-1.05, positive urinary nitrite test findings: OR 2.5, p=0.092, 95% CI 0.86-7.7, chills: OR 2.5, p=0.096, 95% CI 0.84-7.65]. The area under the receiver operating characteristic (ROC) curve of this model was 0.77. Regardless of age, positive urinary nitrite test findings were significantly associated with bacteremia (OR 3.1, p=0.033, 95% CI 1.1-9.2), and chills tended to be associated with bacteremia (OR 2.7, p=0.07, 95% CI 0.93-7.9) The area under the ROC curve of this model was 0.75. Conclusion Bacteremia should be considered in pyelonephritis patients with rapidly assessable factors in outpatient clinic. In particular, a model including a urinary nitrite test has the potential to aid in the prediction of bacteremia.

The efficacy of adjunct tacrolimus treatment in pregnancy outcomes in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) involves multiple organ systems and primarily affects women during their reproductive years. Pregnancy in a woman with SLE may lead to higher rates of disease flares. Little is known regarding which medications are safe to maintain remission and/or treat flares throughout such pregnancies. Here we retrospectively analyzed the efficacy of tacrolimus (TAC) in the pregnancy outcomes of SLE patients. We studied the 54 deliveries of 40 SLE patients over an eight-year period from 2008 to 2016. We used analyses of covariance with adjustments for the propensity score and inverse probability of treatment weights to compare the patient backgrounds between the TAC users and non-TAC users. TAC was administered to the patient in 15 of the 54 (27.8%) pregnancies, and these patients had a significantly higher dose of prednisolone, hypocomplementemia, lower estimated glomerular filtration rate, past history of lupus nephritis, and complication with antiphospholipid syndrome. In the adjusted background of the TAC deliveries, the risks of decreased fetal body weight, low birth weight infant, non-reassuring fetal status (NRFS), and preterm birth were not increased compared to the non-TAC deliveries. Thrombocytopenia and hypertension during the pregnancy were extracted as independent predictive risk factors for decreased fetal body weight and NRFS, respectively. We had anticipated that the maternal and fetal outcomes in the TAC-use deliveries would be poor before the analysis; however, the TAC-use group showed no significant difference in risks contributing to outcomes compared to the non-TAC group, suggesting that adjunct TAC treatment corrected various risk factors during the lupus pregnancies.

Asymmetric public goods game cooperation through pest control

Cooperation in a public goods game has been studied extensively to find the conditions for sustaining the commons, yet the effect of asymmetry between agents has been explored very little. Here we study a game theoretic model of cooperation for pest control among farmers. In our simple model, each farmer has a paddy of the same size arranged adjacently on a line. A pest outbreak occurs at an abandoned paddy at one end of the line, directly threatening the frontier farmer adjacent to it. Each farmer pays a cost of his or her choice to an agricultural collective, and the total sum held by the collective is used for pest control, with success probability increasing with the sum. Because the farmers' incentives depend on their distance from the pest outbreak, our model is an asymmetric public goods game. We derive each farmer's cost strategy at the Nash equilibrium. We find that asymmetry among farmers leads to a few unexpected outcomes. The individual costs at the equilibrium do not necessarily increase with how much the future is valued but rather show threshold behavior. Moreover, an increase in the number of farmers can sometimes paradoxically undermine pest prevention. A comparison with a symmetric public goods game model reveals that the farmer at the greatest risk pays a disproportionate amount of cost in the asymmetric game, making the use of agricultural lands less sustainable.

The vital prognosis of elderly adults living in a group home in their mid-eighties

The purpose of the present study is to evaluate the vital prognoses of elderly people in their mid-eighties living in a group home (GH) compared to age- and sex-matched outpatient clinic (OPC) in an observational study conducted over 6 years. We investigated the association between mortality and general, cardiac, and nutritional parameters, including eicosapentaenoic acid (EPA) in 54 GH residents (83 ± 8 years old) and 57 OPC attendees (83 ± 5 years old). Kaplan-Meier curves and Cox proportional hazard ratio analyses were used to assess the association between EPA drug administration and mortality in the GH residents and OPC attendees, respectively. The 54 GH residents had higher mortality and poorer nutritional states, as indicated by lower EPA/arachidonic acid values (median 0.20 vs 0.55, p < 0.001), and BMI under the condition without EPA drug administration (1800 mg daily) than did the OPC group. The significant factors that differed between survivors and deceased in the GH residents and OPC attendees were nutritional and cardiac factors. Cox proportional hazard ratio analysis confirmed that a possible determinant of the prognosis was a lower incidence of EPA drug administration and lower hemoglobin in GH. Kaplan-Meier curves and Cox proportional hazard ratio analyses revealed that EPA drug administration significantly reduced the relative mortality by 82 % in the GH residents (p < 0.001) but not in the OPC attendees. The vital prognosis in individuals from GHs was potentially improved by EPA drug administration, which was not the case in the OPC group; however, further prospective studies are needed.

Population of the temperate mosquito, Culex pipiens, decreases in response to habitat climatological changes in future

Predictions of the temporal distribution of vector mosquitoes are an important issue for human health because the response of mosquito populations to climate change could have implications for the risk of vector-borne diseases. To elucidate the effects of climate change on mosquito populations inhabiting temperate regions, we developed a Physiology-based Climate-driven Mosquito Population model for temperate regions. For accurately reproducing the temporal patterns observed in mosquito populations, the key factors were identified by implementing the combinations of factors into the model. We focused on three factors: the effect of diapause, the positive effect of rainfall on larval carrying capacity, and the negative effect of rainfall as the washout mortality on aquatic stages. For each model, parameters were calibrated using weekly observation data of a Culex pipiens adult population collected in Tokyo, Japan. Based on its likelihood value, the model incorporating diapause, constant carrying capacity, and washout mortality was the best to replicate the observed data. By using the selected model and applying global climate model data, our results indicated that the mosquito population would decrease and adults' active season would be shortened under future climate conditions. We found that incorporating the washout effect in the model settings or not caused a difference in the temporal patterns in the projected mosquito populations. This suggested that water resources in mosquito habitats in temperate regions should be considered for predicting the risk of vector-borne diseases in such regions.

Development of Collaterals to the Spinal Cord after Endovascular Stent Graft Repair of Thoracic Aneurysms

OBJECTIVES

In thoracic and thoraco-abdominal aortic aneurysm repair, spinal cord injury (SCI) is devastating. Detection of the Adamkiewicz artery might be important for preventing SCI. Although thoracic endovascular stent grafts often occlude the segmental artery, the incidence of SCI in thoracic endovascular aortic repair is thought to be low compared with open repair. This study aimed to evaluate how the Adamkiewicz artery is supplied after segmental arteries are occluded by stent grafts.

METHODS

From March 2007 to August 2015, 32 patients were enrolled whose segmental arteries that were connected to the Adamkiewicz arteries were occluded by stent grafts. Segmental arteries, Adamkiewicz arteries, collateral circulation into the Adamkiewicz arteries, and anterior spinal arteries were pre- and post-operatively evaluated by computed tomography angiography.

RESULTS

Post-operatively, Adamkiewicz arteries were detected in 24 (75%) patients, except for two patients with paraplegia and six without paraplegia. Post-operative Adamkiewicz arteries were the same as pre-operative Adamkiewicz arteries, except for one Adamkiewicz artery that was located at two vertebral levels below the pre-operative level. SCI occurred in two (6.3%) patients. The distribution of feeding arteries into the Adamkiewicz artery post-operatively was divided into three patterns as follows: a segmental artery below the distal landing zone of the stent graft (53%), branches of the left subclavian artery (33%), and a branch of the left external iliac artery (13%).

CONCLUSIONS

The length of the stent graft should be as short as possible. Blood supply to the left subclavian artery should be maintained because segmental arteries below the segmental artery occluded by the stent graft and branches of the left subclavian artery can become collaterals post-operatively.