Topical erythritol combined with L-ascorbyl-2-phosphate inhibits staphylococcal growth and alleviates staphylococcal overgrowth in skin lesions of canine superficial pyoderma

Erythritol (ERT) and L-ascorbyl-2-phosphate (APS) are bacteriostatic, but their effects on staphylococcal skin infections remain unknown. We aimed to determine whether ERT combined with APS inhibits the growth of staphylococci that are commonly isolated from pyoderma skin lesions in dogs. We investigated the individual and combined effects of ERT and APS on the growth of Staphylococcus pseudintermedius, S. schleiferi, and S. aureus using turbidity assays in vitro. Skin lesions from 10 dogs with superficial pyoderma were topically treated with 5% ERT and 0.1% APS for 28 days, and swabbed skin samples were then analyzed using 16S rRNA amplicon sequencing and quantitative real-time PCR (qPCR). Results showed that ERT inhibited S. pseudintermedius growth regardless of harboring the mecA gene, and APS increased the inhibitory effects of ERT against S. pseudintermedius, S. schleiferi, and S. aureus in vitro. Moreover, combined ERT and APS decreased the prevalence of staphylococci on canine skin lesions at the genus level. The combination slightly increased the α-diversity but did not affect the β-diversity of the microbiota. The qPCR results revealed that the combination significantly decreased S. pseudintermedius and S. schleiferi in skin lesions. Topical administration of EPS combined with APS can prevent staphylococcal colonization on the surface of mammalian skin. The results of this study may provide an alternative to systemic antibiotics for treating superficial pyoderma on mammalian skin surfaces.

Proton and Carbon Ion Radiotherapy for Operable Early-Stage Lung Cancer: 3-Year Results of a Prospective Nationwide Registry

PURPOSE/OBJECTIVE(S)

The purpose of this analysis was to report subset analysis as to progression-free survival (PFS) and overall survival (OS) of particle-beam radiation therapy for operable early-stage lung cancer.

MATERIALS/METHODS

Patients of early-stage lung cancer (T1-T2aN0) who were eligible for radical surgery but did not wish to undergo surgery were treated by proton-ion (PT) or carbon-ion (CT) radiation therapy and enrolled in Japanese prospective registry. In this analysis, PFS and OS by clinical stage, tumor location, pathological confirmation and particle-ion type were evaluated.

RESULTS

A total of 274 patients were enrolled and included in efficacy and safety analyses. Most tumors were adenocarcinoma (44%), and 105 (38%) were not histologically confirmed and diagnosed clinically. 250 (91%) of 274 patients had tumors that were peripherally situated. 138 (50%) and 136 (50%) patients were treated by PT and CT, respectively. The median follow-up time for all censored patients was 42.8 months (IQR 36.7 - 49.0). No grade 3 or severe treatment-related toxicity was observed. 3-year PFS was 81% (95% CI;76-86) and OS was 93% (95% CI;89-96), respectively. As to particle-ion type, 3-year PFS were 79.0% and 81.9% in PT and CT (p = 0.19), and 3-year OS were 93.9% and 91.1% in PT and CT (P = 0.72), respectively. For PFS, pathological confirmation, clinical stage was significant factors but there were no significant differences by tumor location or particle-ion type; for OS, clinical stage was significant factor but there was no significant difference on pathological confirmation, tumor location or particle-ion type (Table1). Table 1. 3-year PFS and OS CONCLUSION: Particle therapy for operable early-stage lung cancer resulted in excellent 3-year OS and PFS on each subset.

Clinical Outcomes of Carbon-Ion Radiotherapy for Large-Sized (≥4cm) Hepatocellular Carcinoma

PURPOSE/OBJECTIVE(S)

Radical treatment options for bulky unresectable locally advanced hepatocellular carcinoma (HCC) are limited. The purpose of this study is to evaluate the safety and efficacy of carbon-ion radiotherapy (C-ion RT) for bulky (≥4cm) locally advanced HCC.

MATERIALS/METHODS

We performed a retrospective cohort study of patients with bulky (≥4cm) locally advanced HCC treated by C-ion RT between April 2000 and March 2020 in our institution. The eligibility criteria for this study were: (1) the treatment protocols of 45.0-48.0 Gy/2 fractions or 52.8-60.0 Gy/4 fractions, which proven the safety and efficacy in the past clinical trials; (2) Tumors within 3 intrahepatic lesions and with a maximum tumor diameter of 4 cm or greater; (3) N0M0 status; (4) an Eastern Cooperative Oncology Group performance status of 0 to 2; (5) controllable ascites; (6) Child-Pugh grade was A or B. Overall survival (OS), progression-free survival (PFS), and local control rate (LC) were calculated by the Kaplan-Meier method, and Cox regression analysis was used for multivariate analysis. Adverse events were evaluated by CTCAE ver. 5.0. JMP® 12 (SAS Institute Inc., Cary, NC, USA) was used for all analyses. We defined p < 0.05 as statistically significant.

RESULTS

A total of 187 patients met the criteria and were evaluated. The median patient age was 73 years (range, 37-90), and 139 of 187 patients were male. Child-Pugh grade was A in 163 patients and B in 24. Modified albumin-bilirubin (mALBI) grade was 1 in 96 patients, 2a in 50, and 2b in 41. The number of HCV-related HCC cases was in 80, HBV in 32 and non-B and non-C in 75. In 51 patients, identification of vascular invasion to the first-order branch of the portal vein and/or major hepatic vein was confirmed. The median maximum tumor diameter was 5.1 cm (4.0-13.5 cm). In 76 patients, C-ion RT were treated for recurrence. With a median follow-up period of 25.9 months (range, 1.1-215.1), 2-year overall survival, progression-free survival and local control rates were 68.3% (95% confidence interval [CI], 64.7-72.0%), 39.0% (95% CI, 35.2 - 42.8%) and 86.7% (95% CI, 84.7 - 89.7%), respectively. Late adverse events were observed in 3 patients (1.6%) with Grade 3 liver dysfunction and in 3 patients (1.6%) with Grade 3 skin disorders, but there were no cases of Grade 4 or higher. Multivariate analysis of prognostic factors for overall survival revealed that mALBI grade in 2b(HR:3.13, 1.97-4.78, p<0.0001), tumor status in recurrent treatment (HR:1.50, 1.02-2.21, p = 0.039), the number of tumors in 2 or more (HR:2.16, 1.01-2.17, p = 0.045), and maximum tumor diameter in larger than 6 cm (HR:2.34, 1.50-3.61, p = 0.0001) were the predominant prognostic factors, while age, presence of vascular invasion, AFP and DCP were not.

CONCLUSION

The safety and efficacy of C-ion RT for bulky (≥4cm) locally advanced HCC was demonstrated. These results suggested that C-ion RT may be a new treatment option for locally advanced bulky HCC with no curative treatment options.

Long-Term Clinical Outcome of Carbon Ion Radio Therapy for Hepatocellular Carcinoma in the Caudate Lobe

PURPOSE/OBJECTIVE(S)

Surgical resection is the first-line treatment for hepatocellular carcinoma in the caudate lobe (caudate HCC), but it is often difficult due to the tumor's location. In addition, radiofrequency ablation and transcatheter arterial chemoembolization are also difficult for the same reason. This study aimed to evaluate the safety and efficacy of carbon-ion radiation therapy (C-ion RT) for caudate HCC.

MATERIALS/METHODS

We performed a retrospective cohort study of patients with hepatocellular carcinoma treated by C-ion RT between April 2000 and March 2020 in our institution. The eligibility criteria for this study were: (1) located mainly in the caudate lobe (2) the treatment protocols of 45.0-48.0 Gy/2 fractions or 52.8-60.0 Gy/4 fractions, which proved the safety and efficacy in the past clinical trials; (3) N0M0 status; (4) an Eastern Cooperative Oncology Group performance status (PS) of 0 to 2; (5) controllable ascites. The prescribed dose (Gy) used in this study is relative biological effectiveness (RBE) weighted dose. Overall survival (OS), progression-free survival (PFS), and local control rate (LC) were calculated by the Kaplan-Meier method. Adverse events were evaluated by NCI-CTCAE ver. 5.0. SPSS software version 27.0 (IBM Inc.) was used for all analyses. We defined p-value < 0.05 as statistically significant.

RESULTS

A total of 25 patients met the criteria and were evaluated. The median patient age was 73 years (range 58-89), and 21 of 25 patients were male. The number of patients with PS 0 was 22, PS 1 was 1, and PS 2 was 2. The number of HBV-related HCC cases was in 8, HCV-related HCC cases was in 11, and non-B and non-C cases was in 6. The median maximum tumor diameter was 3.0 cm (1.1-4.8 cm). In 6 patients, identification of vascular invasion to the main trunk of the portal vein and/or major hepatic vein was confirmed. The Child-Pugh (CP) grade was A in 21 patients and B in 4. The modified albumin-bilirubin (mALBI) grade 1 is in 17 patients, 2a in 4, 2b in 4. Prescribed doses were 45 Gy / 2 fr in 3 cases, 48 Gy / 2 fr in 12 cases, 52.8 Gy / 4 fr in 7 cases, and 60 Gy / 4 fr in 3 cases. With a median follow-up period of 43.6 months (range 0.3-85.0), 3-year OS, PFS, and LC were 74% (95% confidence interval [CI], 54.8-93.8%), 32% (95% CI, 11.8-51.4%), and 93% (95% CI, 79.4-106%), respectively. All patients had no Grade 2 or higher adverse events during the observation period.

CONCLUSION

The safety and efficacy of C-ion RT for caudate HCC were demonstrated. These results suggested that C-ion RT may be a promising treatment option for patients with caudate HCC.

Heme Pocket Structure and Its Functional Implications in an Ancestral Globin Protein

Proteins have undergone evolutionary processes to achieve optimal stability, increased functionality, and novel functions. Comparative analysis of existent and ancestral proteins provides insights into the factors that influence protein stability and function. Ancestral sequence reconstruction allows us to deduce the amino acid sequences of ancestral proteins. Here, we present the structural and functional characteristics of an ancestral protein, AncMH, reconstructed to be the last common ancestor of hemoglobins and myoglobins. Our findings reveal that AncMH harbors heme and that the heme binds oxygen. Furthermore, we demonstrate that the ferrous heme in AncMH is pentacoordinated, similar to that of human adult hemoglobin and horse myoglobin. A detailed comparison of the heme pocket structure indicates that the heme pocket in AncMH is more similar to that of hemoglobin than that of myoglobin. However, the autoxidation of AncMH is faster than that of both hemoglobin and myoglobin. Collectively, our results suggest that ancestral proteins of hemoglobins and myoglobins evolved in steps, including the hexa- to pentacoordination transition, followed by stabilization of the oxygen-bound form.

Reopening of ductus arteriosus in idiopathic premature constriction or closure of ductus arteriosus: A case series

BACKGROUND

There is no consensus on managing pregnancy when the fetus is diagnosed with idiopathic premature constriction or closure of the ductus arteriosus (PCDA). Knowing whether the ductus reopens is valuable information for managing idiopathic PCDA. We conducted a case-series study to investigate the natural perinatal course of idiopathic PCDA and examined factors associated with ductal reopening.

METHODS

We retrospectively collected information about the perinatal course and echocardiographic findings at our institution, which, on principle, does not determine delivery timing based on fetal echocardiographic results. We also examined perinatal factors related to the reopening of the ductus arteriosus.

RESULTS

Thirteen cases of idiopathic PCDA were included in the analysis. The ductus reopened in 38% of cases. Among cases diagnosed in <  37 weeks of gestation, 71% reopened, which was confirmed seven days after diagnosis (interquartile range 4-7). Diagnosis earlier in gestation was associated with ductal reopening (p = 0.006). Two cases (15%) developed persistent pulmonary hypertension. No fetal hydrops or death occurred.

CONCLUSIONS

The ductus is likely to reopen when prenatally diagnosed before 37 weeks gestation. There were no complications due to our pregnancy management policy. In idiopathic PCDA, especially if the prenatal diagnosis is made before 37 weeks of gestational age, continuing the pregnancy with careful monitoring of the fetus's well-being is recommended.

Epicardial adipose tissue volume is associated with low-attenuation plaque volume in subjects with or without increased visceral fat: a 3-vessel coronary artery analysis with CT angiography

Background

Low-attenuation plaque (LAP) with a CT value of less than or equal 30 HU on coronary CT angiography (CCTA) is a marker of high-risk plaque features that leads to future acute coronary syndromes. Perivascular and epicardial adipose tissue (EAT) have been shown to be associated with progression of high-risk coronary plaques through metabolic and inflammatory mechanisms. However, association of EAT with LAP volume in three coronary arteries in subjects with or without visceral obesity remain unclear.

Aims

This study aimed to investigate the association of EAT volume (EAV) and coronary 3-vessel LAP volume in subjects with or without visceral obesity who underwent CCTA.

Methods

Patients who underwent CCTA without known coronary artery disease were included in the study (525 patients). Study subjects were classified as having non-obstructive or obstructive coronary artery disease according to the degree of coronary artery stenosis on CCTA. The plaque volume and EAV of the main vessel of the left anterior descending artery, left circumflex artery, and right coronary artery were measured with VINCENT software. Coronary plaque composition was classified as calcified plaque (CP, &gt;150HU), noncalcified plaque (NCP, 30–150HU), and Lap (&lt;30HU). The %LAP volume of the three coronary arteries was classified into quartiles. Multiple logistic regression analysis was used to analyze the factors associated with the %LAP volume.

Results

Compared with subjects without increase visceral fat, subjects with increased visceral fat had a significantly higher BMI, a greater total plaque volume, a greater total %LAP volume, a greater EAV, and a lower mean CT value of EAT. A significant correlation was observed between EAV and %LAP volume (R=0.24, p&lt;0.001). EAV (odds ratio; 1.83, 95% confidence interval 1.071–3.141, p-value 0.027) and type 2 diabetes mellitus (odds ratio 1.76, 95%confidence interval 1.042–3.000, p-value 0.034) appeared to be independent predictors of %LAP volume (Q4), when adjusted by age, gender, BMI&gt;25 kg/m2, visceral fat &gt;100cm2, LogCRP, coronary artery calcium score&gt;300, and obstructive coronary artery disease requiring revascularization.

Conclusion

This study suggests that LAP volume, which reflects the high-risk plaques in the three coronary arteries, is associated with EAV in subjects with or without increased visceral fat. Further research is needed whether pharmacological therapeutic intervention enables the prevention of coronary plaque progression and destabilization through the reduction of EAV in patients.

Funding Acknowledgement

Type of funding sources: None.

Clinical significance of aortic arch plaques simultaneously assessed with coronary atherosclerosis on cardiovascular outcomes in patients undergoing coronary CT angiography

Aims

Computed tomography (CT) coronary angiography is a useful diagnostic imaging modality in assessing presence, severity, and extent of coronary artery disease (CAD). Aortic arch plaques have been shown to be an underlying cause of embolic stroke and also related to increased risk of cardiovascular events. Yet, conventional CTCA imaging protocol does not include aortic arch for the reduction of radiation exposure. This study aimed to investigate prevalence of aortic arch plaques simultaneously assessed by CTCA and their clinical significance in combination with the presence of obstructive CAD for prediction of CVD events in patients with suspected CAD.

Methods

This study consisted of 310 (mean age, 66 years old, 42% female) patients with suspected CAD undergoing CTCA between 2017 and 2019. All CTCA examination was performed with 320-row detector scanner using ECG-triggered prospective gating method. Aortic arch images were simultaneously acquired during CTCA scanning without an increase of contrast media. Using Agatston method, coronary artery calcium score (CACS) was categorized into either of the groups having CACS of 0, 0–99, 100–299, or more than 300. The presence of CAD was reported as non-obstructive or obstructive CAD. High-risk featured aortic plaque was defined as large plaques &gt;4 mm in thickness showing ulceration or protrusion. A composite event of cardiovascular disease, including all-cause mortality, non-fatal myocardial infarction, unplanned hospitalization requiring revascularization or stroke was defined as the primary endpoint.

Results

Patients having CACS of 0, 0–99, 100–299, and &gt;300 were found in 41%, 24%, 15%, 20%%, respectively, where obstructive CAD was diagnosed in 11%. Aortic HRPs in ascending aorta, aortic arch, and thoracic descending aorta were observed in 1.6%, 6.9%, and 15%, respectively. During a mean follow-up period of 2.2 years, the primary endpoint was observed in 27 patients (8.7%). Cox regression hazard model demonstrated an independent association of aortic arch high-risk plaques (HR; 3.2, 95% CI; 1.20–8.64, p=0.02) and obstructive CAD (HR; 3.3, 95% CI; 1.45–7.92, P=0.005) when adjusted by age, CACS, and chronic kidney disease. Kaplan-Meier curve analysis showed a worse outcome of patients with aortic HRP and obstructive CAD compared to those without aortic plaques and obstructive CAD (p&lt;0.001).

Conclusion

This study demonstrated an independent association of aortic arch high-risk featured plaques with CVD events. Further study is warranted whether pharmacological interventional therapies can reduce future CVD risks in patients with CAD and aortic arch plaques.

Funding Acknowledgement

Type of funding sources: None.

Regulatory Switching by Concerted Motions on the Microsecond Time Scale of the Oxygen Sensor Protein FixL

Signal transduction proteins perceive external stimuli in their sensor module and regulate the biological activities of the effector module, allowing cellular adaptation in response to environmental changes. FixL is a dimeric heme protein kinase that senses the oxygen level in plant root nodules to regulate the transcription of nitrogen fixation genes via the phosphorylation of its cognate transcriptional activator. Dissociation of oxygen from the heme induces conformational changes in the protein, converting it from the inactive form for phosphorylation to the active form. However, how FixL undergoes conformational change to regulate kinase activity upon oxygen dissociation remains poorly understood. Here we report time-resolved ultraviolet resonance Raman spectra showing conformational changes for FixL from Sinorhizobium meliloti. We observed spectral changes with a time constant of about 3 μs, which were oxygen-specific. Furthermore, we found that the conformational changes in the sensor and kinase domains are coupled, enabling allosteric control of kinase activity. Our results demonstrate that concerted structural changes on the microsecond time scale serve as the regulatory switch in FixL.

Drag of a cylindrical object in a two-dimensional granular environment

The drag of a cylindrical object in a two-dimensional granular environment is numerically studied. It is found that the drag law is fitted by the sum of the yield force and the dynamic force, the latter of which is reproduced by a simple collision model. The angular dependence of the radial stress on the surface of the object is given by the Gaussian below the yield force. The probability of the velocity drops of the object is investigated above the yield force, where this probability is independent of the packing fraction and the drag force.

Cumulative incidence of femoral localized periosteal thickening (beaking) preceding atypical femoral fractures in patients with rheumatoid arthritis

The incidence of localized periosteal thickening (LPT, also termed beaking) of the lateral cortex that often precedes an atypical femoral fracture (AFF) was not high in patients with rheumatoid arthritis (RA) but incomplete AFFs developed in two patients. Higher-dose prednisolone was a significant risk factor for LPT in patients with RA.

INTRODUCTION

Atypical femoral fractures (AFFs) are stress fractures; bisphosphonate (BP) use is a major risk factor for the development of such fractures. Localized periosteal thickening (LPT, also termed beaking) of the lateral cortex often precedes a complete or incomplete AFF. We evaluated the incidence of latent LPT in patients with rheumatoid arthritis (RA), to evaluate LPT progression, and to define LPT risk factors.

METHODS

A total of 254 patients with RA were included; all underwent annual X-ray evaluation, dual-energy X-ray absorptiometry, and analyses of serum and bone metabolic markers for 2-3 years. LPT of the lateral cortex was sought in femoral X-rays.

RESULTS

The incidence of LPT was 2.4% (6/254). Among patients on both BP and prednisolone (PSL) at enrollment, the incidence was 2.3% (3/131). Two femurs of two patients with LPT developed incomplete AFFs; LPT was extensive and associated with endosteal thickening. One patient had been on BP and PSL and microscopic polyangiitis was comorbidity. The other was on a selective estrogen receptor modulator and PSL. A daily PSL dose >5 mg (OR 11.4; 95%CI 2.15-60.2; p = 0.004) and higher-dose methotrexate (OR 1.22; 95%CI 1.01-1.49; p = 0.043) were significant risk factors for LPT.

CONCLUSIONS

The incidence of latent LPT was not high (2.4%) but incomplete AFFs developed in two RA patients. Higher-dose PSL because of a comorbid disease requiring glucocorticoid treatment other than RA or refractory RA were risk factors for LPT; X-ray screening for latent LPT would usefully prevent complete AFFs.

Rheology of two-dimensional crushable granular materials

The rheology of two-dimensional crushable granular materials under shear is numerically studied using the discrete element method. We find that the mean fragment size changes as the shear strain increases while the shear stress is almost independent of this mean size. The fragment size distribution is found to follow a power law. In particular, the exponent in the intermediate fragment size regime becomes approximately – 11/6, which is almost independent of the shear rate.

Presenteeism among workers: health-related factors, work-related factors and health literacy

BACKGROUND

Presenteeism is an important factor in workers' health. However, few studies have examined how variables such as socio-economic status, health status, workplace status and health literacy correlate with and affect presenteeism.

AIMS

To assess the correlates of presenteeism with a focus on health-related factors, work-related factors and health literacy.

METHODS

We conducted a cross-sectional study of 2914 Japanese workers from one company. We used a self-administered questionnaire to assess socio-demographic characteristics, health status, work environment, presenteeism and health literacy.

RESULTS

Forty-one per cent of participants were under 40 years of age and 70% were male. We found that 59% of the participants were at high risk of presenteeism. Presenteeism was associated with sex, age, household income, marital status, health-related factors (i.e. self-rated health status, dietary choices, exercise habits), work-related factors (i.e. workplace support, job demands, job control) and health literacy. Logistic regression analyses indicated that presenteeism was associated with self-rated health status, overtime hours, workplace support, job demands, job control and health literacy after adjusting for sex, age and income.

CONCLUSIONS

Health-related factors, work-related factors and health literacy are all associated with presenteeism. Improving the workplace environment, especially factors such as overtime working hours, workplace support, job demands and job control, and increasing health literacy may reduce presenteeism among general office workers.

Thigh intramuscular fat predicts the prognosis in patients in non-ischemic cardiomyopathy with reduced ejection fraction

Background

Skeletal muscle atrophy is an independent prognostic predictor for patients with chronic heart failure, and the concept of sarcopenia is drawing attention. Furthermore, the importance of not only muscle mass but also intramuscular fat (IMF) has been pointed out. However, there is a lack of consensus on the implications of ectopic fat for the prognosis in patients with non-ischemic cardiomyopathy.

Purpose

We investigated whether ectopic fat in the thigh affects the prognosis with non-ischemic cardiomyopathy.

Methods

We recruited 105 patients who were diagnosed with non-ischemic cardiomyopathy by cardiac catheterization and echocardiographic date between September 2017 and November 2019. Finally 73 patients with reduced EF (EF 40% or less) enrolled in this prospective study. Functional status was evaluated by using cardiopulmonary exercise test at baseline. All patients were measured quantity of epicardial fat and thigh IMF percentage (%IMF) using computed tomography scan. Demographic, laboratory and echocardiographic date were collected from the patients' medical records. Clinical endpoints were unexpected readmission.

Results

During the follow-up period 18 patients had adverse events. The %IMF was significantly higher in the group with adverse events than without (5.57±5.70 and 3.02±2.44%, respectively; p&lt;0.01). Spearman correlation coefficient analysis showed a modest correlation between %IMF and lower limb extension strength (Spearman r=−0.280; p=0.0315), but there was no significant correlation between %IMF and exercise tolerance such as anaerobic threshold and peak oxygen uptake. Patients were divided into 2 groups according to the median values of %IMF. Kaplan-Meier analysis demonstrated that events were significantly higher in the high %IMF group (log-rank p=0.033). Multivariate Cox regression analysis adjusted for left ventricular end-diastolic diameter and peak ventricular oxygen consumption found %IMF as an independent factor of adverse events (hazard ratio 1.545; 95% confidential interval 1.151–2.087; p=0.004).

Conclusions

In non-ischemic cardiomyopathy patients with reduced EF, %IMF may have important adverse consequences such as increased cardiac-related events.

Kaplan-Meier curves

Funding Acknowledgement

Type of funding source: None

Regional muscle-adipose distribution is different in patients with heart failure with preserved or reduced ejection fraction

Background

Epicardial adipose tissue (EAT) has been recognized to contribute inflammatory activity and atherosclerosis. On the other hand, it has been reported that the volume of EAT is lower in non-ischemic heart failure (HF) patients than healthy individuals. However, the difference in regional muscle-adipose distribution including EAT between HF with preserved ejection fraction (HFpEF) and HF reduced ejection fraction (HFrEF) has not been investigated. In addition, we investigated whether distribution of body composition contributed to exercise capacity.

Methods

The study included 105 non-ischemic HF patients diagnosed by cardiac catheterization between September 2017 and November 2019. Epicardial, abdominal and thigh muscle and adipose tissue volume were measured by computed tomography (CT), and exercise tolerance was evaluated by symptom-limited cardiopulmonary exercise test.

Results

Patients were divided into 2 groups according to the left ventricular ejection fraction, ≥40% as HFpEF (n=28) or &lt;40% as HFrEF (n=77). There was no significant difference comorbidity, including hypertension, dyslipidemia, chronic kidney disease, and body mass index. Plasma B-type natriuretic peptide level was significantly higher in HFrEF than HFpEF group (146.2 vs 393.2 pg/ml, p&lt;0.01), whereas, high-sensitive troponin T level was not different between two groups. Although there was no significant difference in BMI between two groups, the volume of EAT was significantly higher in HFpEF than HFrEF group (81.8 vs 136.4 ml, p=0.01). On the other hand, HFpEF had more thigh adipose tissue compared with HFrEF group (54.6 vs 42.1 ml, p=0.03). There were negative correlations between EAT volume and parameters of exercise capacity such as anaerobic threshold (r=−0.42, p&lt;0.01) and peak VO2 (r=−0.32, p&lt;0.01). Muscle volume itself does not corelate with these parameters.

Conclusion

In patient with nonischemic HF, the pattern of regional adipose distribution may have important role in pathologically. HFpEF and HFrEF has different pattern despite similar body mass index. These differences may be related to impaired exercise tolerance in these 2 different types of HF.

Correlation between EAT and AT, peak VO2

Funding Acknowledgement

Type of funding source: None

Unique Electronic Structures of the Highly Ruffled Hemes in Heme-Degrading Enzymes of Staphylococcus aureus, IsdG and IsdI, by Resonance Raman and Electron Paramagnetic Resonance Spectroscopies

Staphylococcus aureus uses IsdG and IsdI to convert heme into a mixture of staphylobilin isomers, 15-oxo-β-bilirubin and 5-oxo-δ-bilirubin, formaldehyde, and iron. The highly ruffled heme found in the heme-IsdI and IsdG complexes has been proposed to be responsible for the unique heme degradation products. We employed resonance Raman (RR) and electron paramagnetic resonance (EPR) spectroscopies to examine the coordination and electronic structures of heme bound to IsdG and IsdI. Heme complexed to IsdG and IsdI is coordinated by a neutral histidine. The trans ligand is hydroxide in the ferric alkaline form of both proteins. In the ferric neutral form at pH 6.0, heme is six-coordinated with water as the sixth ligand for IsdG and is in the mixture of the five-coordinated and six-coordinated species for IsdI. In the ferrous CO-bound form, CO is strongly hydrogen bonded with a distal residue. The marker lines, ν₂ and ν₃, appear at frequencies that are distinct from other proteins having planar hemes. The EPR spectra for the ferric hydroxide and cyanide states might be explained by assuming the thermal mixing of the d-electron configurations, (d_xy)²(d_xz,d_yz)³ and (d_xz,d_yz)⁴(d_xy)¹. The fraction for the latter becomes larger for the ferric cyanide form. In the ferric neutral state at pH 6.0, the quantum mechanical mixing of the high and intermediate spin configurations might explain the peculiar frequencies of ν₂ and ν₃ in the RR spectra. The heme ruffling imposed by IsdG and IsdI gives rise to unique electronic structures of heme, which are expected to modulate the first and subsequent steps of the heme oxygenation.

Record-high sensitivity compact multi-slot sub-wavelength Bragg grating refractive index sensor on SOI platform

In this paper, a high sensitivity compact multi-slot sub-wavelength Bragg grating refractive index (RI) sensor was investigated. The structural parameters were optimized for higher sensitivity to RI change of the surrounding medium from viewpoints of a wavelength shift, an extinction ratio and a transmission loss, and a record-high sensitivity was experimentally demonstrated with a compact size. In this sensor, the first side-lobe at the Bragg grating (BG) stop-band end was focused as a sensing peak wavelength for moderate transmission loss and efficient sensing. To realize the compactness, a period count of the BG was kept as small as 20. By increasing the RI of the surrounding medium, the sensing peak shifts toward a longer wavelength side; thus due to the high sharpness and easy tracing of the first side-lobe, the device worked as an efficient RI sensor. The structural optimization was carried out by using 3D finite-difference time-domain (FDTD) simulation approach, and also influences of the structural parameters to sensitivities were discussed. Based on these optimized parameters, the devices were fabricated using the lift-off technique. By exposing the sensor to various liquid samples with different RIs such as pure water, sugar-dissolved water with various concentrations, acetone and isopropyl alcohol (IPA), a record-high sensitivity of 730 nm/RIU was attained for a sensor fabricated on SOI platforms with a length of as small as 9.5 µm and a transmission loss of 3 dB.

Phase I/II study of adding intraperitoneal paclitaxel in patients with pancreatic cancer and peritoneal metastasis

BACKGROUND

Intraperitoneal chemotherapy using paclitaxel is considered an experimental approach for treating peritoneal carcinomatosis. This study aimed to determine the recommended dose, and to evaluate the clinical efficacy and safety, of the combination of intravenous gemcitabine, intravenous nab-paclitaxel and intraperitoneal paclitaxel in patients with pancreatic cancer and peritoneal metastasis.

METHODS

The frequencies of dose-limiting toxicities were evaluated, and the recommended dose was determined in phase I. The primary endpoint of the phase II analysis was overall survival rate at 1 year. Secondary endpoints were antitumour effects, symptom-relieving effects, safety and overall survival.

RESULTS

The recommended doses of intravenous gemcitabine, intravenous nab-paclitaxel and intraperitoneal paclitaxel were 800, 75 and 20 mg/m² respectively. Among 46 patients enrolled in phase II, the median time to treatment failure was 6·0 (range 0-22·6) months. The response and disease control rates were 21 of 43 and 41 of 43 respectively. Ascites disappeared in 12 of 30 patients, and cytology became negative in 18 of 46. The median survival time was 14·5 months, and the 1-year overall survival rate was 61 per cent. Conversion surgery was performed in eight of 46 patients, and those who underwent resection survived significantly longer than those who were not treated surgically (median survival not reached versus 12·4 months). Grade 3-4 haematological toxicities developed in 35 of 46 patients, whereas non-haematological adverse events occurred in seven patients.

CONCLUSION

Adding intraperitoneal paclitaxel had clinical efficacy with acceptable tolerability.

AB1172 IMPROVEMENT OF DEPRESSION BY JOINT SURGERY IN ESTABLISHED RHEUMATOID ARTHRITIS; RESULTS FROM MULTICENTER PROSPECTIVE COHORT STUDY FOR EVALUATION OF JOINT SURGERY ON PATIENT’S REPORTED OUTCOME

Background:

Total management including reconstructive joint surgery and rehabilitation should be needed for further improvements of physical function for long-standing RA patients. In these days, it is very important to evaluate the effectiveness of joint surgery as well as drug therapy based on patient-reported outcome (PRO)

Objectives:

The purpose of this study is to explore the relationship among depression, clinical variables and other PROs including physical function and to explore whether joint surgery can improve the depression.

Methods:

Multicenter prospective observational cohort study was conducted among patients who underwent elective joint surgery for RA from April 2012 to March 2016 (Study registration: UMIN000012649). In this study, we collected data at baseline and at 6 or 12 months after the surgery. These data were as follow; age, sex, disease duration, drug therapies, and disease activity (DAS), TUG, and patient-reported outcome [HAQ-DI, EQ-5D (QOL), pain and BDI-II (depression)]. Correlation between BDI-II and other variables were determined using multiple liner regression analysis.

Results:

Totally, 346 patients before elective joint surgery were analyzed cross-sectionally. Mean age, disease duration, pain VAS, DAS28, HAQ-DI, EQ-5D and BDI-II were 64.2 years, 17.0 years, 36.2 mm, 3.02, 1.11, 0.641 and 13.0, respectively. 52.6% of elective joint surgeries were in upper limbs and 47.4% were in lower limbs. Multiple liner regression analysis showed that HAQ-DI [B:-0.099 (95%CI:-0.117- -0.08) β:-0.48] pain VAS [B:-0.002 (95%CI:-0.002- -0.001) β:-0.26] and BDI-II [B:-0.003 (95%CI:-0.005- -0.002) β:-0.19] had significant impact on EQ-5D. Furthermore, HAQ-DI [B:3.78 (95%CI:2.54- 5.06) β: 0.33] and pain VAS [B: 0.062 (95%CI: 0.023- 0.101) β 0.17] had significant impact on BDI-II. Especially, walking and eating were independent factors for BDI-II in HAQ-DI categories. These results were confirmed in longitudinal analyses using results from joint surgery in lower limbs (LL; n=138) and upper limbs (UL; n=165), respectively. BDI-II was remarkably improved from 12.1 (mean) to 10.5 in LL and from 14.2 (mean) to 11.9 in UL. Change in HAQ-DI had significant impact on that in BDI-II [LL; B:3.183 (95%CI:0.301- 6.065) β:0.229, and UL; B:2.55 (95%CI:0.19- 4.92) β:0.19] while that in painVAS did not. Especially, the improving in walking category by LL [B:1.38 (95%CI:0.06- 2.70) β:0.18] and in hygiene category by UL [B:2.11 (95%CI:0.79- 3.42) β:0.24] were relevant factors for improving of BDI-II.

Conclusion:

Depression is an important patient-reported outcome for QOL in established RA patients. Improving of physical function with joint surgery in both lower and upper limbs caused improving of depression status. Rheumatologists should take the joint surgery into consideration as effective intervention for treatment of established RA patients with treatment.

Acknowledgments:

This study was funded by a grant from the Ministry of Health, Labour and Walfare (h2424YN002-00) to Naoki Ishiguro.

We thank Drs Tanaka S, Haga N, Yukioka M, Hashimoto J, Miyahara H, Niki Y, Kimura T, Oda H, Funahashi K for their contribution to this study and all medical staff members of each institute for their data collection efforts for their data collection efforts.

Disclosure of Interests:

Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Masayo Kojima: None declared, Hajime Ishikawa: None declared, Keiichiro Nishida Grant/research support from: K. Nishida has received scholarship donation from CHUGAI PHARMACEUTICAL Co., Eisai Co., Mitsubishi Tanabe Pharma and AbbVie GK., Speakers bureau: K. Nishida has received speaking fees from CHUGAI PHARMACEUTICAL Co., Eli Lilly, Janssen Pharmaceutical K.K., Eisai Co. and AYUMI Pharmaceutical Corporation., Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

SAT0047 RISK FACTORS FOR THE POSTOPERATIVE DELAYED WOUND HEALING IN PATIENTS WITH RHEUMATOID ARTHRITIS TREATED WITH A BIOLOGICAL AGENT

Background:

It has been suggested that perioperative use of biological disease-modifying anti-rheumatic drugs (bDMARDs) in rheumatoid arthritis (RA) patients carries risks for the surgical-site infection and the delayed wound healing (DWH); however, the risk of DWH with perioperative use of bDMARDs has not reached a general consensus.

Objectives:

This retrospective study aimed to investigate the risk factors associated with DWH after orthopedic surgery in RA patients treated with bDMARDs.

Methods:

We reviewed medical records of 277 orthopedic procedures for 188 RA patients treated with bDMARDs between from 2014 to 2017 in Niigata Rheumatic Center. As preoperative nutritional status assessment, we evaluated body mass index (BMI), prognostic nutritional index (PNI), and CONtrolling NUTritional status (CONUT). In addition, we evaluated DAS28-CRP, DAS28-ESR, face scale for pain, global health (GH), and Health Assessment Questionnaire-Disability Index (HAQ-DI) to assess the disease activity. Univariate and multivariate logistic regression analyses were performed to evaluate the risk factor for DWH.

Results:

The major characteristics of the patients in 277 procedures were mean age of 63.2 years old and mean disease duration of 18.2 years. Surgical site were hand and wrist (145 procedures), foot and ankle (76), hip and knee (31), elbow and shoulder (24), and spine (1). Seventy-four patients were treated with tocilizumab, 62 with etanercept, 55 with golimumab, 49 with abatacept, 16 with infliximab, 15 with adalimumab, and 6 with certolizumab. According to nutritional assessment in PNI and CONUT, 63% (n=175) and 47% (n=130) were normal nourished patients, respectively.

In 277 procedures, DWH were identified in 24 patients (8.6%). The following variables were significant in the univariate analyses: disease duration (OR 1.053; 95% CI 1.010–1.099; p=0.016), foot and ankle surgery (OR 7.091; 95% CI 2.130–23.603; p=0.001), tocilizumab (OR 0.286; 95% CI 0.093–0.881; p=0.029) (Table 1). These variables were entered into a multivariate model, and it was revealed that pre-operative use of tocilizumab (OR 0.265; 95% CI 0.074–0.953; p=0.042) and procedures in the foot and ankle (OR 6.915; 95% CI 1.914–24.976; p=0.003) were associated with an increased risk of DWH (Table 1).

Conclusion:

As previous study on tocilizumab described, the current retrospective study suggested that pre-operative use of tocilizumab and procedures in the foot and ankle were risk factors for DWH. Pre-operative disease activity and nutritional status were not independent risk factors for an increase in the prevalence of DWH.

References:

[1] Momohara S, Hashimoto J, Tsuboi H et al. Analysis of perioperative clinical features and complications after orthopaedic surgery in rheumatoid arthritis patients treated with tocilizumab in a real-world setting: Results from the multicentre tocilizumab in perioperative period (TOPP) study. Modern rheumatology. 2013, 23: 440-9.

Disclosure of Interests:

Shunji Okita: None declared, Hajime Ishikawa: None declared, Asami Abe: None declared, Satoshi Ito Speakers bureau: Abbvie,Eisai, Akira Murasawa: None declared, Keiichiro Nishida Grant/research support from: K. Nishida has received scholarship donation from CHUGAI PHARMACEUTICAL Co., Eisai Co., Mitsubishi Tanabe Pharma and AbbVie GK., Speakers bureau: K. Nishida has received speaking fees from CHUGAI PHARMACEUTICAL Co., Eli Lilly, Janssen Pharmaceutical K.K., Eisai Co. and AYUMI Pharmaceutical Corporation., Toshifumi Ozaki: None declared

AB0297 THE LONG-TERM OBSERVATION OF PATIENTS WITH RHEUMATOID ARTHRITIS WHO ACHIEVED A BIO-FREE CONDITION WITH ADALIMUMAB

Background:

Biological disease-modifying antirheumatic drugs (bDMARDs) caused a paradigm shift in the treatment of rheumatoid arthritis (RA). However, their high cost is a burden for patients and the national medical economy.

Objectives:

To analyze the long-term outcomes of patients with RA who achieved a bio-free condition (BF) with adalimumab (ADA).

Methods:

We followed 25 patients (male 6, female 19) who discontinued ADA with clinical remission (CR), and one female with a low disease activity (LDA), over 19.4 ±7.8 months of ADA treatment1). At the introduction of ADA, the average age was 51.2 ± 11.9 years old, and the average disease duration was 45.1 ± 48.4 months. The disease activity measured by disease activity score based on C-reactive protein (DAS28-CRP) was defined as follows: CR, <2.3; LDA, 2.3 - 2.7; moderate DA, 2.7 -4.1; and high DA, > 4.1, since the DAS28-CRP tends to be lower than the DAS28-based on the erythrocyte sedimentation rate in Japanese patients2).

Results:

We lost one patient with a transfer to another hospital. Four patients re-started ADA due to flare (DAS28-CRP>2.7) but achieved CR (in BF) again with the intensification of the treatment (dose increase or initiation of prednisolone [PSL] and/or conventional synthetic [cs] DMARDs such as tacrolimus or iguratimode). The DAS28-CRP significantly decreased from 3.45 ± 1.32 at base line (BL) to 1.55 ± 0.41 (p<0.0001) at BF. It remained 1.59 ± 0.59 (n=25) at 24 months after BF, 1.56 ± 0.39 (n= 20) at 48 months, 1.8 ± 0.7 (n=11) at 60 months. At the last observation, every patient remained in CR up to 84 months (n=2, Figure 1). The modified health assessment questionnaire score significantly decreased from 0.42 ± 0.46 (BL, n=19) to 0.02 ± 0.05 (p<0.002) at BF. It remained 0.03 ± 0.07 (n=19) at 24 months and 0.06 ± 0.14 (n=14) at 48 months, 0.04 ± 0.08 at 60 months (n=9). The PSL dose (mg/day) decreased from 3.2 ± 3.3 (BL) to 2.2 ± 2.8 at BF and 2.04 ± 2.13 (n=25) at 24 months, 1.73 ± 1.9 (n=20) at 48 months, and 1.6 ± 2.3 (n=11) at 60 months, but there were no significant changes. The methotrexate (MTX) dose (mg/week) increased from 10.1 ± 2.9 (BL) to 10.6 ± 2.6 (p< 0.78) at BF, 10.4 ± 3.3 (n=25) at 24 months, 10.7 ± 3.4 (n=20) at 48 months, 10.4 ± 3.1 at 60 months (not significant). The number of csDMARDs significantly increased from 0.8 ± 0.6 (BL) to 1.3 ± 0.9 (p<0.001, at BF), 2.56 ± 0.94 (n=25) at 24 months, 1.6 ± 1.01 (n=20) at 48 mnths, and 1.6 ± 2.3 at 60 months (n=11, Figure 2).

Conclusion:

BF can be sustained with an adequate dose of MTX and combination of csDMARDs.

References:

[1]Ito S, et al. An analysis of the biological disease-modifying antirheumatic drug-free condition of adalimumab-treated rheumatoid arthritis patients. Intern Med 58: 511-519, 2019

[2]Inoue E, et al. Comparison of Disease Activity Score (DAS)28-erythrocyte sedimentation rate and DAS28- C-reactive protein threshold values. Ann Rheum Dis. 66:407-409, 2007.

Disclosure of Interests:

Satoshi Ito Speakers bureau: Abbvie,Eisai, Shunsuke sakai: None declared, Yoichi Kurosawa: None declared, Daisuke Kobayashi: None declared, Ryo Okabayashi: None declared, Asami Abe: None declared, Hiroshi Otani: None declared, Kiyoshi Nakazono: None declared, Akira Murasawa: None declared, Ichiei Narita: None declared, Hajime Ishikawa: None declared

SAT0147 EFFICACY AND SAFETY OF IGURATIMOD AS FIRST-LINE DISEASE-MODIFYING ANTIRHEUMATIC DRUG THERAPY FOR PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Although methotrexate is the anchor drug, it took some days to check contraindications, such as interstitial pneumonia, hepatitis B virus infection, and latent tuberculosis infection. Therefore, we sometimes start rheumatoid arthritis (RA) treatment with other disease-modifying antirheumatic drug (DMARD) in daily clinical setting. Iguratimod (IGU) is a newly developed DMARD approved in Japan in September 2012, and the efficacy of IGU for DMARD naïve patients has not been thoroughly evaluated.

Objectives:

The aim of this prospective single-center study was to demonstrate the efficacy and safety of IGU when used as a first-line daily DMARD for patients with RA in a clinical setting.

Methods:

Enrolled patients included those diagnosed with RA according to the 2010 American College of Rheumatology/European League against Rheumatism (ACR/EULAR) classification criteria who took IGU as a first-line DMARD at Niigata Rheumatic Center between April 2016 and December 2018 (IGU group). There were no constraints regarding the addition or withdrawal of other DMARDs. Details of the patients’ background, clinical parameters, and laboratory findings were obtained, including C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), matrix metalloprotease-3 (MMP-3), rheumatoid factor (RF), Disease Activity Score for 28-joint counts based on the erythrocyte sedimentation rate (DAS28-4[ESR]), Clinical Disease Activity Index (CDAI), and Health Assessment Questionnaire Disability Index (HAQ-DI). The efficacy of IGU was evaluated at week 24. The IGU group’s data were then compared with 64 patients who took salazosulfapyridine or bucillamine as first-line DMARD in our hospital (other DMARD group). The data were expressed as median values. Comparisons between the parameters were performed using nonparametric method.

Results:

Forty-three patients (15 males, 28 females) received IGU as a first-line DMARD for RA. The age was 69.0 years and the duration of disease was 2.0 months. Twenty patients received prednisolone (PSL) concomitantly at a median dose of 5.0 mg/day. At 24 weeks medications were utilized in patients as follows: IGU in 36 (83.7 %), methotrexate in 18 (41.2%), PSL in 17 (39.5%), BUC in 10 (23.2 %), and biological DMARD in 7 (15.2 %) patients. Although 7 patients discontinued taking IGU due to liver enzyme elevation (n=4), nausea (n=1), creatinine elevation (n=1), and skin rash (n=1) during the 24-week period, serious adverse events requiring hospitalization were not observed. Clinical parameters that improved from baseline after 24 weeks of treatment included: ESR from 42.0 mm/h to 16.0 mm/h with p < 0.001; CRP from 0.70 mg/dL to 0.10 mg/dL with p< 0.001; MMP-3 from 136 ng/mL to 91.5 ng/mL with a p value of 0.11; RF went from 18.0 IU/mL to 8.00 IU/mL with p < 0.001; DAS28(4)-ESR dropped from 5.13 to 2.73 with p< 0.001; CDAI dropped from 20.0 to 5.00 with p< 0.001, and HAQ-DI decreased from 0.55 to 0.00 with p< 0.001. Patients who achieved a good or moderate response based on EULAR response at 24 weeks, included 90.7% in the IGU group versus 70.5% in the other DMARD group (Fisher`s exact test, p=0.046). The retention rate of the IGU group was 81.4 %, roughly equivalent to the 81.2% retention rate in the other DMARD group (Log-rank test, p=0.733).

Conclusion:

Our study indicates IGU is safe and effective for DMARD naïve RA patients. Starting treatment with IGU might be a new and effective strategy for RA patients without previous use of a DMARD.

Disclosure of Interests:

Daisuke Kobayashi: None declared, Eriko Hasegawa: None declared, Yoko Wada: None declared, Satoshi Ito Speakers bureau: Abbvie,Eisai, Asami Abe: None declared, Kiyoshi Nakazono: None declared, Akira Murasawa: None declared, Ichiei Narita: None declared, Hajime Ishikawa: None declared

A case of laboratory cross-contamination of Mycobacterium tuberculosis identified using comparative genomics

BACKGROUND

Two false-positive tuberculosis (TB) cases in Yamagata Prefecture, Japan, 2016.

OBJECTIVE

To report the effectiveness of comparative genomics of Mycobacterium tuberculosis for identification of cross-contamination cases.

DESIGN

Case report of laboratory cross-contamination.

RESULTS

Beginning with detection of an identical genotype in two M. tuberculosis strains using variable number of tandem repeat typing, we suspected M. tuberculosis cross-contamination of specimens collected in a mycobacteriology laboratory based on epidemiological investigations. This suspicion was confirmed using comparative genomics of the two M. tuberculosis strains and a strain from an epidemiologically unrelated specimen from the same batch as the two strains in the mycobacteriology laboratory. All strains had an identical genomic sequence with no single nucleotide variants.

CONCLUSION

Comparative genomics, which offers the highest discrimination power, is a potent tool for identifying laboratory cross-contamination using epidemiological investigations.

Spin waves and spin-state transitions in a ruthenate high-temperature antiferromagnet

Ruthenium compounds serve as a platform for fundamental concepts such as spin-triplet superconductivity¹, Kitaev spin liquids^2-5 and solid-state analogues of the Higgs mode in particle physics^6,7. However, basic questions about the electronic structure of ruthenates remain unanswered, because several key parameters (including Hund's coupling, spin-orbit coupling and exchange interactions) are comparable in magnitude and their interplay is poorly understood, partly due to difficulties in synthesizing large single crystals for spectroscopic experiments. Here we introduce a resonant inelastic X-ray scattering (RIXS)^8,9 technique capable of probing collective modes in microcrystals of 4d electron materials. We observe spin waves and spin-state transitions in the honeycomb antiferromagnet SrRu₂O₆ (ref. ¹⁰) and use the extracted exchange interactions and measured magnon gap to explain its high Néel temperature^11-16. We expect that the RIXS method presented here will enable momentum-resolved spectroscopy of a large class of 4d transition-metal compounds.

Potent Antimalarial Activity of Two Arenes Linked with Triamine Designed To Have Multiple Interactions with Heme

Based on the idea that compounds designed to exhibit high affinity for heme would block hemozoin formation, a critical heme-detoxification process for malarial parasites, we synthesized a series of compounds with two π-conjugated moieties at terminal amino groups of triamine. These compounds exhibited moderate to high antimalarial activities in vitro toward both chloroquine-sensitive and chloroquine-resistant Plasmodium falciparum. In a P. berghei-infected mouse model, 3a and 12a showed potent antimalarial activities compared to artesunate, as well as a prolonged duration of antimalarial effect. We found a good correlation between protective activity against hemin degradation and antimalarial activity. Compounds 8b and 3a strongly inhibited hemozoin formation catalyzed by heme detoxification protein.