The ssgB gene is required for the early stages of sporangium formation in Actinoplanes missouriensis

In Streptomyces, multiple paralogs of SsgA-like proteins (SALPs) are involved in spore formation from aerial hyphae. However, the functions of SALPs have not yet been elucidated in other actinobacterial genera. Here, we report the primary function of an SsgB ortholog (AmSsgB) in Actinoplanes missouriensis, which develops terminal sporangia on the substrate mycelia via short sporangiophores. Importantly, AmSsgB is the sole SALP in A. missouriensis. The transcription of AmssgB was upregulated during sporangium formation, consistent with our previous findings that AmssgB is a member of the AmBldD regulon. The AmssgB null mutant (ΔAmssgB) strain formed non-globose irregular structures on the substrate mycelium. Transmission electron microscopy revealed that the irregular structures contained abnormally septate hypha-like cells, without an intrasporangial matrix. These phenotypic changes were restored by complementation with AmssgB. Additionally, analysis of the heterologous expression of seven SALP-encoding genes from Streptomyces coelicolor A3(2) (ssgA-G) in the ΔAmssgB strain revealed that only ssgB could compensate for AmSsgB deficiency. This indicated that SsgB of S. coelicolor A3(2) and AmSsgB have comparable functions in A. missouriensis. In contrast to the ΔAmssgB strain, the ftsZ-disrupted strain showed a severe growth defect and produced small sporangium-like structures that swelled to some extent. These findings indicate that AmSsgB is crucial for the early stages of sporangium formation, not for spore septum formation in the late stages. We propose that AmSsgB is involved in sporangium formation by promoting the expansion of the "presporangium" structures formed on the tips of the substrate hyphae.

IMPORTANCE

SsgB has been proposed as an archetypical SsgA-like protein with an evolutionarily conserved function in the morphological development of spore-forming actinomycetes. SsgB in Streptomyces coelicolor A3(2) is involved in spore septum formation. However, it is unclear whether this is the primary function of SsgBs in actinobacteria. This study demonstrated that the SsgB ortholog (AmSsgB) in Actinoplanes missouriensis is essential for sporangium expansion, which does not seem to be related to spore septum formation. However, the heterologous expression of ssgB from S. coelicolor A3(2) restored morphological abnormalities in the ΔAmssgB mutant. We propose that the primary function of SsgB is to initiate sporulation in differentiating cells (e.g., aerial hyphae in Streptomyces and "presporangium" cells in A. missouriensis) although its molecular mechanism remains unknown.

Modulation of pain perception through transcranial alternating current stimulation and its nonlinear relationship with the simulated electric field magnitude

BACKGROUND

Oscillatory activities observed in multiple regions are closely associated with the experience of pain. Specifically, oscillatory activities within the theta- and beta-frequency bands, observed in the left dorsolateral prefrontal cortex (DLPFC), have been implicated in pain perception among healthy individuals and those with chronic pain. However, their physiological significance remains unclear.

METHODS

We explored the modulation of pain perception in healthy individuals by theta- and beta-band transcranial alternating current stimulation (tACS) over the left DLPFC and examined the relationship between the modulation effect and magnitude of the electric field elicited by tACS in the left DLPFC using computational simulation.

RESULTS

Our findings revealed that both theta- and beta-tACS increased the heat pain threshold during and after stimulation. Notably, the simulated electric field magnitude in the left DLPFC exhibited an inverted U-shaped relationship with the pain modulation effect for theta-tACS.

CONCLUSIONS

Our study findings suggested that there would be an optimal electric field strength to produce a high analgesic effect for theta-tACS.

SIGNIFICANCE

The application of theta- and beta-tACS interventions targeting the left DLPFC might facilitate the treatment of chronic pain. Furthermore, the attainment of effective pain modulation via theta-tACS over the DLPFC warrants the use of optimal stimulus intensity.

Effect of baseline urinary glucose levels on the relationship between sodium-glucose cotransporter 2 inhibitors and serum uric acid in Japanese patients with type 2 diabetes mellitus

In patients with type 2 diabetes mellitus (T2DM), controlling serum uric acid (SUA) and blood glucose levels is important. Moreover, sodium-glucose cotransporter 2 (SGLT2) inhibitors decrease SUA levels by accelerating urinary uric acid excretion. We investigated the effect of baseline urinary glucose levels on the relationship between SGLT2 inhibitors and SUA levels. We conducted a retrospective observational study using the electronic medical records of patients with T2DM of Kindai University Nara Hospital (April 2013 to March 2022). We divided the patients into two groups according to their baseline urinary glucose levels: the N-UG group, which included patients with negative urinary glucose strip test results (-), and the P-UG group, which included patients with positive urinary glucose strip test results (± or more). The changes in SUA levels before and after SGLT2 inhibitor administration were investigated. For comparison, the changes in SUA levels before and after the prescription of antidiabetic agents, excluding SGLT2 inhibitors, were also investigated. Our results revealed that SGLT2 inhibitors significantly decreased the SUA levels in patients in the N-UG group but tended to decrease its levels in those in the P-UG group. Regardless of the urinary glucose status at baseline, the administration of SGLT2 inhibitors may be useful for patients with T2DM to prevent the complications of hyperuricemia.

Predicting habitual water intake from lifestyle questions

OBJECTIVE

Previous studies have used selective recall and descriptive dietary record methods, requiring considerable effort for assessing food and water intake. This study created a simplified lifestyle questionnaire to predict habitual water intake (SQW), accurately and quickly assessing the habitual water intake. We also evaluated the validity using descriptive dietary records as a cross-sectional study.

SUBJECTS AND METHODS

First, we used crowdsourcing and machine learning to collect data, predict water intake records, and create questionnaires. We collected 305 lifestyle-related questions as predictor variables and selective recall methods for assessing water intake as an outcome variable. Random forests were used for the machine learning models because of their interpretability and accurate estimation. Random forest and single regression correlation analysis were augmented by the synthetic minority oversampling that trained the model. We separated the data by sex and evaluated our model using unseen hold-out testing data, predicting the individual and overall habitual water intake from various sources, including non-alcoholic beverages, alcohol, and food.

RESULTS

We found a 0.60 Spearman's correlation coefficient for total water intake between the predicted and the selective recall method values, reflecting the target value to be achieved. This question set was then used for feasibility tests. The descriptive dietary record method helped to obtain a ground-truth value. We categorized the data by gender, season, and source: non-alcoholic beverages, alcohol, food, and total water intake, and the correlation was confirmed. Consequently, our results showed a Pearson's correlation coefficient of 0.50 for total water intake between the predicted and the selective recall method values.

CONCLUSIONS

We hypothesize that dissemination of SQW can lead to better health management by easily determining the habitual water intake.

[A Case Study of Successful Breast Cancer Treatment after Recovery from Drug-Induced Interstitial Lung Disease]

Drug-induced interstitial lung disease(DILD)is a possible complication of many anticancer drugs. When DILD occurs during breast cancer treatment, choosing the right drug for subsequent treatment is often difficult. In our first case, the patient developed DILD during dose-dense AC(ddAC)therapy; however, the disease resolved with steroid pulse therapy, and the patient underwent surgery without disease progression. In the second case, a patient on anti-HER2 therapy for recurrent disease developed DILD in response to docetaxel plus trastuzumab plus pertuzumab administered to treat T-DM1 after progressive disease. In this report, we describe a case of DILD that did not worsen and the patient had successful treatment outcome.

AB0381 ULTRASONOGRAPHY TO PREDICT FLARE AFTER DISCONTINUATION OF BIOLOGICS IN PATIENTS WITH RHEUMATOID ARTHRITIS IN REMISSION

Background

Ultrasonography (US) has been suggested to be useful in predicting flare in patients with rheumatoid arthritis (RA) after discontinuation of biological disease-modifying antirheumatic drugs (bDMARDs).

Objectives

This study aimed to investigate whether US can predict flare after discontinuation of bDMARDs in RA patients who have achieved stringent remission criteria.

Methods

We prospectively enrolled RA patients who maintained a simplified disease activity index ≤ 3.3 and discontinued bDMARDs and measured clinical assessment and US every 2-3 months for 2 years. The US examination was performed on 40 joints using the semi-quantitative method of 0-3 on the Grey-scale (GS) and Power Doppler (PD), and the total values for each patient were used as the GS score and PD score. Joints graded as GS score ≥ 2 or PD score ≥ 1 were counted as US arthritis. In addition, tendons at 36 sites were counted with or without tendinitis/tenosynovitis to obtain a tendon score.

Results

Thirty-six patients were enrolled and two patients who dropped out early without flare were excluded from the comparative analyses. At baseline, the median GS score was 7, PD score was 0, US arthritis was 0, and tendon score was 0. The total PD score was 0 in 26 patients (72%) and it was 1 in 5 patients (14%). There were no significant differences in US findings between the relapse group (20 patients) and the non-relapse group (14 patients). Positive and negative predictive value for PD-positive findings (total PD score ≥1) were 60% and 42%, and for total PD score ≥2 were 60% and 41%, respectively.

Conclusion

The PD score in the US findings at the time of bDMARDs discontinuation was not predictive for future disease flare.

Disclosure of Interests

Takehisa Ogura Speakers bureau: AbbVie G.K, Ayako Hirata: None declared, Takaharu Kagtagiri: None declared, Yuto Takakura: None declared, Hideto Kameda Speakers bureau: AbbVie G.K., Asahi Kasei Pharma, Astellas Pharma Inc., Bristol-Myers Squibb, Chugai Pharmaceutical Co. Ltd., Eisai Co. Ltd., Eli Lilly Japan K.K., Gilead Sciences, Janssen Pharmaceutical K.K., Mitsubishi Tanabe Pharma, Novartis Pharma K.K., and Sanofi Pharma, Grant/research support from: AbbVie G.K., Asahi Kasei Pharma, Astellas Pharma Inc., Chugai Pharmaceutical Co. Ltd., Eisai Co. Ltd., Mitsubishi Tanabe Pharma, Novartis Pharma K.K., and Sanofi Pharma

Impact of heart rate reduction on recurrence after catheter ablation of persistent atrial fibrillation

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Johnson & Johnson KK

OnBehalf

OCVC Arrhythmia Investigators

Background

Predicting heart rate (HR) after restoration of sinus rhythm (SR) remains one of the challenges when performing catheter ablation (CA) of persistent atrial fibrillation (AF).

Purpose

To evaluate the association between pre-ablation HR during AF and post-ablation HR during SR, and whether the HR reduction is associated with AF recurrence.

Methods

The analysis was performed from the EARNEST-PVI trial, a randomized controlled trial designed to assess a CA strategy for persistent AF, which was conducted in the Osaka region of Japan. After excluding patients with beta-blocker prescription, a total of 216 patients (median age, 67 years; 20% female; 23% long-standing persistent AF) with AF rhythm at baseline and SR at discharge were enrolled in this study. Baseline HR during AF and post-ablation HR during SR was measured on admission and at discharge using the 12-lead electrocardiograms, respectively.

Results

There was a mild correlation between baseline HR (median 82 [interquartile range 72-95] bpm) and post-ablation HR (78 [48-117] bpm) (r = 0.27, p <0.001). Reduction in HR was positively associated with baseline HR (r = 0.79, p <0.001) and was negatively associated with post-ablation HR (r = - 0.37, p <0.001). During the follow-up of 1 year, 56 patients (25.9%) experienced AF recurrence. HR reduction had the higher diagnostic accuracy in predicting AF recurrence than HR at baseline and HR after CA (area under the curve, 0.625; 95% confidence interval, 0.557–0.690; p = 0.003). AF recurrence rate was significantly higher in 141 patients with smaller HR reduction (cut-off, <14bpm) than those with larger HR reduction (31.9% vs. 14.7%, p = 0.009). After adjustment of age, gender, long-standing persistent AF, and CA strategy, HR reduction of <14 bpm was a significant predictor of AF recurrence (hazard ratio, 2.32; 95% confidence interval, 1.20–4.51; p = 0.013).

Conclusions

There was a mild correlation between HR during AF and HR after restoration of SR in patients underwent CA of persistent AF. HR reduction after restoration of SR predicted AF recurrence.

Time-dependent changes in serum magnesium levels in patients receiving cetuximab with low baseline serum sodium levels

Cetuximab causes electrolyte abnormalities, such as hypomagnesemia, hypokalemia, and hypocalcemia. However, little is known about the relationships between the onset of hypomagnesemia, patient background before administration, and time-dependent changes in serum magnesium levels. Therefore, we examined the patient backgrounds that influenced the onset of hypomagnesemia and the time-dependent changes in serum magnesium levels in patients receiving cetuximab. A retrospective study was performed to investigate patients with advanced or recurrent colorectal cancer or head and neck cancer, treated with a cetuximab regimen from 2012 to 2020 at Kindai University Nara Hospital. In total, 52 patients who met the inclusion criteria were enrolled in this study. The serum magnesium level was significantly lower in the hyponatremia before the administration group than in the non-hyponatremia group (p < 0.001). Univariate logistic regression analysis revealed that the baseline serum sodium levels (odds ratio [OR]: 0.741, 95% confidence interval [CI]: 0.588-0.934) and the combination of magnesium oxide tablet (OR: 0.997, 95% CI: 0.995-0.999) were one of the independent factors for hypomagnesemia. These results indicated that hyponatremia before administration may be an indicator of serum magnesium levels after administration of cetuximab. Cetuximab-induced hypomagnesemia may be predicted using baseline serum sodium levels, and hypomagnesemia may be prevented by administration of magnesium oxide tablets. Our findings provided new evidence for the management of serum magnesium levels in patients receiving cetuximab.

Reappraising the role of baseline plasma C-reactive protein levels on recurrence after catheter ablation of persistent atrial fibrillation: insight from EARNEST-PVI trial

Background

Subclinical inflammation is an important pathogenesis of developing and sustaining atrial fibrillation (AF). Because AF itself contribute to the inflammatory response, the role of baseline subclinical inflammation on AF recurrence after catheter ablation (CA) remains controversial in patients with persistent AF.

Purpose

To evaluate whether baseline plasma C-reactive protein (CRP) levels, a sensitive marker of inflammation, are associated with AF recurrence following CA.

Methods

The analysis was performed from the EARNEST-PVI trial, a randomized controlled trial designed to assess a CA strategy for persistent AF, which was conducted in the Osaka region of Japan. A total of 441 patients (median age, 67 years; 26% female; 25% long-standing persistent AF) whose plasma CRP levels were measured at baseline were included in this study.

Results

At baseline, a median (interquartile range) of plasma CRP level was 0.10 [0.06–0.19] mg/dl. Plasma CRP levels significantly increased at discharge (0.83 [0.21–1.84] mg/dl, p&lt;0.001) and decreased 1 year after CA (0.10 [0.05–0.20] mg/dl, p=0.040) compared to the baseline value. During the follow-up of 1 year, 115 patients (26%) experienced AF recurrence, and the incidence was significantly higher in 124 patients with low CRP levels at baseline (cut-off ≤0.06 mg/dl) than the other 317 patients (33.9% vs. 23.0%, p=0.017). After adjustment of age, gender, body mass index, long-standing persistent AF, CA strategy, and plasma brain natriuretic peptide levels, low plasma CRP levels was a significant predictor of AF recurrence (hazard ratio, 1.51; 95% confidence interval, 1.02–2.24; p=0.042).

Conclusions

Low plasma CRP levels at baseline predicted AF recurrence in the EARNEST-PVI trial. Reappraising the role of CRP on AF recurrence may be needed in patients with persistent AF.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Johnson & Johnson KK

Renal function and arrhythmia outcomes in persistent atrial fibrillation patients after catheter ablation: subanalysis of the EARNEST-PVI trial

Background

Atrial fibrillation (AF) reduces the renal function. Renal dysfunction and AF often coexist. Catheter ablation (CA) of persistent AF can maintain a sinus rhythm and may improve the renal function.

Purpose

We sought to elucidate whether the estimated glomerular filtration rate (eGFR) in patients with persistent AF was increased after CA, especially with the presence of an AF recurrence.

Methods

We enrolled 487 persistent AF patients whose eGFR data were available both before and 1-year after the CA out of 512 patients in the EARNEST-PVI trial.

Results

The mean age was 65±9 year and 113 patients (24.8%) had long-standing persistent AF. We compared the eGFR at baseline with that 1-year after the CA. AF recurrences were recognized in 118 patients (25.8%). The eGFR was similar between the group without recurrence and that with recurrence at baseline (without AF recurrence vs. with AF recurrence; 63.8±14.3 vs. 62.7±13.6 mL/min/1.73m2, p=0.46). In patients without AF recurrence, the G1, G2, G3a, G3b, G4, and G5 were 13 (3.8%), 198 (58.4%), 98 (28.9%), 26 (7.7%), 3 (0.9%), and 1 (0.3%), respectively at baseline. In the patients with AF recurrence, the G1, G2, G3a, G3b, G4, and G5 were 3 (2.5%), 68 (57.8%), 38 (32.2%), 6 (5.1%), 3 (2.5%), and 0 (0%), respectively at baseline. The ΔeGFR was significantly higher in the patients without AF recurrence than in those with AF recurrence (without AF recurrence vs. with AF recurrence; 5.1 [−0.3, 10.8] vs. 3.0 [−3.0, 7.6], p=0.0033). In the patients without AF recurrence, a better eGFR class at 1-year after the CA than in those before the CA was recognized in 75 patients (22.1%), while it was recognized in 19 patients (16.1%) with AF recurrences.

Conclusion

Successful catheter ablation in patients with persistent AF led to a better renal outcome.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This study was funded by Medtronic, Johnson & Johnson, and Abbott.

Differences in quality of life improvement with pulmonary vein isolation alone vs. more extensive ablation of persistent atrial fibrillation: insights from the EARNEST-PVI trial

Background

Improving the quality of life (QoL) is one of the main purposes of catheter ablation (CA) of persistent atrial fibrillation (AF). QoL improvement in persistent AF patients has not been fully clarified. The EARNEST-PVI trial was a multi-center randomized trial comparing clinical outcomes of pulmonary vein isolation (PVI) alone and more intensive ablation in addition to PVI including complex fractionated atrial electrogram (CFAE) and linear ablation (PVI plus).

Purpose

To investigate the QoL change after persistent AF ablation and the differences between the PVI-alone strategy and the PVI plus strategy.

Methods

In the EARNEST-PVI trial, patients with persistent AF who underwent an initial catheter ablation (n=512) were randomly assigned in a 1:1 ratio to either PVI alone or PVI plus. Quality of life was assessed at baseline and at 12 months after ablation for AF using the 36-Item Short Form Health Survey. Scores were also converted to a physical health component summary (PCS), a mental health component summary (MCS) and a role/social component summary (RCS).

Results

In the EARNEST-PVI trial, the PVI alone strategy was associated with higher recurrence rate compared with the PVI plus additional ablation strategy. After excluding 68 patients for whom preoperative or postoperative QoL assessment was not available, 222 patients were evaluated respectively. Overall, significant improvements in PCS (46.2±11.4 to 48.7±11.4]), MCS (50.1±8.8 to 54.3±8.6) and RCS (44.6±13.3 to 48.6±11.3) occurred 12 months after ablation (P&lt;0.001, respectively). Although significant QoL improvement occurred in both PVI alone and PLI plus strategies, the changes in PCS was greater in the PVI-plus than that in PVI-alone (3.5±10.3 vs 1.5±10.6, P=0.04).

Conclusions

Ablation for persistent atrial fibrillation improved both physical and mental quality of life. The PVI-plus strategy showed greater improvement in physical QoL.

Funding Acknowledgement

Type of funding sources: None. QoL improvement

POS1396 DAMAGE PROGRESSION OF FINGER JOINT CARTILAGE EVALUATED BY ULTRASOUND AND X-RAY IN PATIENTS WITH RHEUMATOID ARTHRITIS (RA)

Background:

Cartilage damage in RA has been evaluated by joint space narrowing (JSN) in X-ray, while it is not a direct evaluation of cartilage. Previously we have confirmed the usefulness of the direct imaging of finger joint cartilage by ultrasound (US) in patients with RA [1].

Objectives:

We aimed to examine the temporal changes of US cartilage thickness in RA patients.

Methods:

We enrolled 53 RA patients in whom the cartilage thickness of finger joints was measured by US and had radiographs of both hands at baseline and 1-year later. The cartilage of metacapophalangeal and proximal interphalangeal joints of 2nd to 5th fingers were bilaterally visualized at the middle portion from a longitudinal dorsal view. Cartilage thickness was measured from the base of the cartilage to the interface artefact at the cartilage surface by static images. In addition, the JSN of the corresponding joints was scored using a hand X-ray by van der Heijde-modified Sharp method. Continuous variables from the two groups were analyzed using the Mann-Whitney U test or Wilcoxon signed-rank test. The relationships among the continuous variables were assessed using the Spearman’s rank correlation coefficient.

Results:

The median age of the patients was 68 years and the median disease duration was 6.3 years. The sum of total cartilage thickness from 16 joints per patient ranged from 3.1 to 9.1mm (median 6.5 mm) at baseline, and it was significantly correlated with total JSN score of the same joints (ρ=-0.63, p<0.001). The cartilage thickness was inversely correlated with disease duration (rho=-0.40, p=0.003), but not associated with age nor height. The decrease in cartilage thickness over 1 year was evident in patients with persistent moderate to high disease activity by the DAS28-CRP (n=10; median -6.2%) as compared with other patients (n=43; median -1.2%, p=0.004 versus active patients).

Conclusion:

This pilot study demonstrated the progression of cartilage damage by sustained RA activity, supporting the validity and usefulness of joint cartilage thickness evaluation by ultrasound in patients with RA.

References:

[1]Ogura T, et al. Arthritis Care Res 2019 Oct 25.

Table 1.

SALIENT FEATURES OF THE 9 PATIENTS PRESENTING WITH RETINAL TOXICITY DUE TO HCQ

Sl.NoAgeGenderWeight(Kg)Primary DiagnosisDoseDuration(Years)Detection Method UsedRecommended Dose(mg/Day)Received Dose(mg/Day)Cumulative Dose(grams)FUNDUSEXAM.SD-OCTHVF10-2FAF147F58SLE2904004383RPE ChangesThinning/Photoreceptor LossDefects seen-220F46SLE2302001462Multiple Small Drusens In Paramacular AreaMultipleDrusensNormalPerifoveal autofluorescence spots-drusens323F50SLE2504001461RPE ChangesRPEDisruptionsDefects seen-430F55SLE275200731NormalNormalParacentral Scotoma-550F49RA2452005117Early Bull’s Eye MaculopathyRPEAtrophyDefects seen-672F60RA30020073010RPE AtrophyFR AbsentRPEAtrophyGeneral reduction in sensitivity-765M57.4RA2872001462RPE ChangesRPEDisruptions & Thinning NotedDefects seen-862F70RA3502002193Chorioretinal AtrophyAlteredRPEMembraneDefects seen-959M71.6RA3582002924RPE ChangesRPEDisruptionsNormal-

F:Female; M:Male; SLE:Systemic Lupus Erythematosus; RA: Rheumatoid Arthritis, FUNDUS EXAM.: Fundus Examination; SD-OCT:Spectral Domain-Optical Coherence Tomography, HVF 10-2:Humphrey Visual Field 10-2; FAF: Fundus Autofluorescence, RPE:Retinal Pigment Epithelium; FR:Foveal Reflex

Disclosure of Interests:

None declared

Impact of Proteinuria and Low eGFR on Lifetime Risk of Cardiovascular Disease Death: A Pooled Analysis of Data From the Evidence for Cardiovascular Prevention From Observational Cohorts in Japan Study

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): H20–Junkankitou [Seishuu]–Ippan–013; H23–Junkankitou [Seishuu]–Ippan–005; H26-Junkankitou [Seisaku]-Ippan-001; H29–Junkankitou–Ippan–003 and 20FA1002

OnBehalf

EPOCH-JAPAN

Introduction

Absolute risk of Lifetime risk (LTR) is useful estimate for risk communication compared with short term risk or relative risk especially for young people. Proteinuria is leading cause of end-stage kidney disease (ESKD) and independent risk factor for cardiovascular disease (CVD). Although nonproteinuric renal disease is global burden of ESKD, it has been poorly focused. To date, there have been no reports of impact of proteinuria and low eGFR on LTR with the outcome of CVD death in Asian population.

Purpose

We aimed to estimate LTR of CVD death stratified by the status of proteinuria and low eGFR.

Methods

We used modified Kaplan-Meier approach to estimate the remaining lifetime risk of cardiovascular death based on EPOCH-JAPAN(Evidence for Cardiovascular Prevention From Observational Cohorts in Japan) database. LTR was estimated at each index age starting from 40 years for those with proteinuria and without proteinuria stratified by low eGFR, which is defined as eGFR &lt;60 ml/min/1.73 m². Participants were classified into three groups, which were those with proteinuria (Proteinuria (+)), those without proteinuria with low eGFR (Proteinuria (-)/Low eGFR (+)), those without proteinuria without low eGFR (Proteinuria (-)/Low eGFR (-)).

Results

A total of 47,292 participants from 9 cohorts was included in the analysis. Mean follow-up period was 14.6 years with 690,463 person years and total CVD death was 1,075 in men and 1,193 in women. The LTRs at the index age of 40 years were as follows: 17.7% (95% confidence interval: 15.4 – 19.0%) in Proteinuria (-)/Low eGFR (-) group, 26.2% (20.2 – 31.1%) in Proteinuria (-)/low eGFR (+) group, 24.5% (15.1 – 29.3%) in Proteinuria (+) group for men; 15.3%(13.7 – 16.5%), 29.9%(14.7 – 46.8%) , 28.3%(19.4 – 34.7%) for women.

Conclusions

We observed that those without proteinuria with low eGFR have equivalently high LTR with those with proteinuria. These results indicate that even in the absence of proteinuria, low eGFR has high impact on LTR. Lifestyle modification from young age is necessary to prevent from renal dysfunction.

Regulation of Sporangium Formation, Spore Dormancy, and Sporangium Dehiscence by a Hybrid Sensor Histidine Kinase in Actinoplanes missouriensis: Relationship with the Global Transcriptional Regulator TcrA

The rare actinomycete Actinoplanes missouriensis forms terminal sporangia containing a few hundred flagellated spores. In response to water, the sporangia open and release the spores into external environments. The orphan response regulator TcrA functions as a global transcriptional activator during sporangium formation and dehiscence. Here, we report the characterization of an orphan hybrid histidine kinase, HhkA. Sporangia of an hhkA deletion mutant contained many distorted or ectopically germinated spores and scarcely opened to release the spores under sporangium dehiscence-inducing conditions. These phenotypic changes are quite similar to those observed in a tcrA deletion mutant. Comparative RNA sequencing analysis showed that genes controlled by HhkA mostly overlap TcrA-regulated genes. The direct interaction between HhkA and TcrA was suggested by a bacterial two-hybrid assay, but this was not conclusive. The phosphorylation of TcrA using acetyl phosphate as a phosphate donor markedly enhanced its affinity for the TcrA box sequences in the electrophoretic mobility shift assay. Taking these observations together with other results, we proposed that HhkA and TcrA compose a cognate two-component regulatory system, which controls the transcription of the genes involved in many aspects of morphological development, including sporangium formation, spore dormancy, and sporangium dehiscence in A. missouriensisIMPORTANCEActinoplanes missouriensis goes through complex morphological differentiation, including formation of flagellated spore-containing sporangia, sporangium dehiscence, swimming of zoospores, and germination of zoospores to filamentous growth. Although the orphan response regulator TcrA globally activates many genes required for sporangium formation, spore dormancy, and sporangium dehiscence, its partner histidine kinase remained unknown. Here, we analyzed the function of an orphan hybrid histidine kinase, HhkA, and proposed that HhkA constitutes a cognate two-component regulatory system with TcrA. That HhkA and TcrA homologues are highly conserved among the genus Actinoplanes and several closely related rare actinomycetes indicates that this possible two-component regulatory system is employed for complex morphological development in sporangium- and/or zoospore-forming rare actinomycetes.

Metallic Glacial Glass Formation by a First-Order Liquid-Liquid Transition

The glacial phase, with an apparently glassy structure, can be formed by a first-order transition in some molecular-glass-forming supercooled liquids. Here we report the formation of metallic glacial glass (MGG) from the precursor of a rare-earth-element-based metallic glass via the first-order phase transition in its supercooled liquid. The excellent glass-forming ability of the precursor ensures the MGG to be successfully fabricated into bulk samples (with a minimal critical diameter exceeding 3 mm). Distinct enthalpy, structure, and property changes are detected between MGG and metallic glass, and the reversed "melting-like" transition from the glacial phase to the supercooled liquid is observed in fast differential scanning calorimetry. The kinetics of MGG formation is reflected by a continuous heating transformation diagram, with the phase transition pathways measured at different heating rates taken into account. The finding supports the scenario of liquid-liquid transition in metallic-glass-forming liquids.

AB1123 PROGRESSION OF FINGER JOINT CARTILAGE DAMAGE EVALUATED BY ULTRASOUND IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Cartilage damage in rheumatoid arthritis (RA) has been evaluated by joint space narrowing (JSN) in X-ray, despite the fact that it is not a direct evaluation of cartilage. We have recently reported that direct evaluation of finger joint cartilage thickness evaluated by ultrasound (US) is valid and useful for patients with RA1).

Objectives:

In this study, we aimed to examine the progression of cartilage damage in RA patients.

Methods:

Forty-six patients with RA who had completed the US evaluation of finger joint cartilage thickness at baseline and after 1 year were included in this study. The cartilage thickness of metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of 2nd to 5th fingers were bilaterally visualized and measured at the middle portion of MCP and PIP joints from a longitudinal dorsal view, with approximately 90 degrees flexion. Cartilage thickness was measured from the base of the cartilage to the interface artefact at the cartilage surface by calculating the pixel counts on DICOM images.

Results:

In patients, 78% were female, the median age was 68 years and the median disease duration of the patients was 6 years. The median DAS28-CRP at baseline was 2.6. The sum of total cartilage thickness from 16 joints per patient ranged from 3.1 to 9.1 mm (median 6.4 mm) at baseline, and it was significantly correlated with disease duration (ρ=-0.423, p=0.003). A significant decrease from the baseline in the cartilage thickness (median -1.6%) was observed after 1 year (p=0.041). Furthermore, patients with persistently moderate/high disease activity for 1 year by DAS28-CRP (n=9) showed a greater decrease in the cartilage thickness than the remaining patients with controlled disease activity (n=37) (median -5.9% versus -1.5%, respectively, p=0.029).

Conclusion:

This study further supported the validity and usefulness of joint cartilage thickness evaluation by US in patients with RA.

References:

[1]Ogura T, et al. Arthritis Care Res 2019 Oct 25.

Disclosure of Interests:

Takehisa Ogura: None declared, Ayako Hirata: None declared, Sayaka Takenaka: None declared, Yuki Inoue: None declared, Takaharu Kagtagiri: None declared, Yuto Takakura: None declared, Hideki Ito: None declared, Hideto Kameda Grant/research support from: Abbvie, Asahi-Kasei, Chugai, Eisai, Mitsubishi-Tanabe and Novartis, Consultant of: Abbvie, Boehringer, Celgene, Eli Lilly, Janssen, Novartis, Sanofi, UCB, Speakers bureau: Abbvie, Asahi-Kasei, BMS, Chugai, Eisai, Eli Lilly, Janssen, Mitsubishi-Tanabe, Novartis and Pfizer

Serum modified HDL was associated with cardiovascular disease in a Japanese community-based cohort

Background

Previous studies have shown that high density lipoprotein (HDL) is protective against cardiovascular disease (CVD). However, recent studies suggested that function of HDL was more important than HDL cholesterol levels. The present study aimed to clarify the relationship between modified HDL levels and CVD incidence.

Methods

LOX-1 (lectin-like oxidized LDL receptor) is the receptor that mediates modified LDL (low density lipoprotein) activity; however, some lipoproteins with apolipoprotein A1 (Apo A-1) are also bonded to LOX-1. In this study, serum LOX-1 ligand containing Apo A-1 was defined as modified HDL, which were measured by our new development method. We conducted a nested case-control study in a Japanese cohort study, involving 11,002 community dwellers. During 4.0 years follow-up, we observed 127 new CVD onsets. For each CVD case, age and sex matched three controls were randomly selected (N = 381). Serum samples collected at baseline survey stored at − 80 °C were used for the measurement of modified HDL. We estimated multivariable-adjusted odds ratio (OR) and 95% confidence interval (CI) for the association between modified HDL levels and CVD by conditional logistic regression.

Results

Modified HDL levels were associated with increased risk of CVD (OR for one unit increase of log transformed modified HDL, 2.05: 95% CI, 1.16-3.62) after adjustment for body mass index, hypertension, diabetes, LDL cholesterol, HDL cholesterol, lipid lowering agents, chronic kidney disease, smoking and alcohol drinking. The magnitude of OR was almost equivalent to those of hypertension and diabetes, which were 2.33 (95% CI, 1.37-3.98) and 2.61 (95% CI, 1.48-4.59), respectively. On the other hands, other lipids markers showed relatively weak associations with CVD.

Conclusions

Serum modified HDL, i.e., LOX-1 ligand containing Apo A-1, might be a novel predictive marker for CVD in apparently healthy individuals.

Key messages

Recent epidemiologic studies suggested that function of high-density lipoprotein (HDL) was more important than HDL cholesterol level itself to predict cardiovascular disease. Modified HDL measured by a novel cell-free, non-fluorescent method as LOX-1 ligand containing Apo A-1, was a predictive marker for CVD after adjusting for other traditional risk factors.

P3471Anti-inflammatory effects of direct oral anticoagulants in patients with non-valvular atrial fibrillation: insights from 2216 patients in the DIRECT registry

Background

Several previous studies reported anti-inflammatory effect of direct oral anticoagulant (DOAC). However, it was limited to basic pathological data with small sample size. Real-world large clinical data is still scarce.

Methods

We conducted a single-center prospective observational registry of NVAF patients treated with DOACs: the DIRECT registry (UMINehz745.034333283). All patients with nonvalvular atrial fibrillation (NVAF) (N=2216) who were users of dabigatran (N=648), rivaroxaban (N=538), apixaban (N=599), or edoxaban (N=431) from June 2011 to November 2017 were enrolled (71.6±10.8 years, 36.4% female, follow-up duration: 407.2±388.3 days). High sensitive C-reactive protein (hsCRP) test was performed before (within 3 months from the start) and after the start of DOAC prescription (6±3 months after the start). Patients with a hsCRP value >1.00 mg/dL were excluded from the analysis due to possibility of other systemic inflammatory conditions. The present post-hoc study of the DIRECT registry assessed anti-inflammatory effect of DOAC. Pre-hsCRP and post-hsCRP were compared by Wilcoxon Signed Ranks test.

Results

A total of 1,855 patients were analyzed in the present study (71.0±10.7 years, 677/1,855 (36%) females). In the overall cohort, hsCRP significantly decreased after the start of DOAC prescription (pre median 0.08 interquartile range [0.04–0.17] mg/dL vs. post 0.06 [0.03–0.12] mg/dL, p<0.001). The significant reduction of hsCRP was consistent across all DOACs (p=0.301) [dabigatran (N=562), pre 0.08 [0.04–0.1625] mg/dL vs. post 0.06 [0.03–0.12] mg/dL, p<0.001: rivaroxaban (N=457), pre 0.07 [0.04–0.16] mg/dL vs. post 0.07 [0.03–0.125] mg/dL, p<0.001: apixaban (N=494), pre 0.09 [0.04–0.19] mg/dL vs. post 0.06 [0.03–0.13] mg/dL, p<0.001: edoxaban (N=342), pre 0.08 [0.04–0.19] mg/dL vs. post 0.06 [0.03–0.13] mg/dL, p<0.001].

Conclusions

The present study of DIRECT registry suggested anti-inflammatory effect of DOAC presented as a significant reduction of hsCRP. Although further investigation would be warranted to evaluate the clinical significance of the suppressed systemic inflammation, the recent favorable clinical data of DOACs might be attributed to the present finding.

Distortion of Local Atomic Structures in Amorphous Ge-Sb-Te Phase Change Materials

The local atomic structures of amorphous Ge-Sb-Te phase-change materials have yet to be clarified and the rapid crystal-amorphous phase change resulting in distinct optical contrast is not well understood. We report the direct observation of local atomic structures in amorphous Ge_{2}Sb_{2}Te_{5} using "local" reverse Monte Carlo modeling dedicated to an angstrom-beam electron diffraction analysis. The results corroborated the existence of local structures with rocksalt crystal-like topology that were greatly distorted compared to the crystal symmetry. This distortion resulted in the breaking of ideal octahedral atomic environments, thereby forming local disordered structures that basically satisfied the overall amorphous structure factor. The crystal-like distorted octahedral structures could be the main building blocks in the formation of the overall amorphous structure of Ge-Sb-Te.

Intracellular localization of sirtuin and cell length analysis of Lactobacillus paracasei suggest possible role of sirtuin in cell division and cell shape regulation

Sirtuin has been associated in prolonging lifespan of different model organisms. It has been shown to have an enzymatic activity of NAD+-dependent protein deacetylation targeting acetylated proteins. To determine targets and possible roles of sirtuin (LpSirA) in the Lactobacillus paracasei BL23, deletion (ΔsirA), sirtuin overexpressor (highsirA) and GFP fusion (highsirA-Venus) strains were generated, and microscopic localization and cell length analysis were done. Microscopic analysis revealed localization of LpSirA at cell division plates, at cell poles and all throughout the cell length in a spiral manner. Cell length analysis revealed that 46.9% of the ΔsirA cells were observed to be shorter (<2 μm), whereas 12.6% of the highsirA cells were observed to be longer (>4 μm) in comparison with the wild-type with only 17.1% short cells and 5.3% long cells. Our results suggest that sirtuin may have an essential role in cell division and cell shape regulation.

Regulation of sporangium formation by the orphan response regulator TcrA in the rare actinomycete Actinoplanes missouriensis

The rare actinomycete Actinoplanes missouriensis forms terminal sporangia containing a few hundred flagellated spores, which can swim in aquatic environments after release from sporangium. However, gene regulation for its characteristic morphological development is largely unknown. Here, we report the functional analysis of an orphan response regulator, TcrA, which is encoded next to the chemotaxis-flagellar gene cluster. The tcrA null (ΔtcrA) mutant formed sporangium, in which sporulation proceeded. However, many distorted spores were produced and some spores ectopically germinated in the mutant sporangia. In addition, spores were hardly released from the mutant sporangia. A comparative RNA-Seq analysis between the wild-type and ΔtcrA strains showed that TcrA upregulated the transcription of more than 263 genes, which were integrated into 185 transcriptional units. In silico searches identified a 21-bp direct repeat sequence, 5'-nnGCA(A/C)CCG-n₄ -GCA(A/C)CCGn-3', as the TcrA box, which was confirmed by electrophoretic mobility shift assays. Finally, we identified 34 transcriptional units as the TcrA regulon. TcrA seems to regulate a few hundred genes through the transcriptional activation of three FliA-family sigma factor genes besides its own regulon. We concluded that TcrA is a global transcriptional activator that controls many aspects of sporangium formation, including flagellar biogenesis, spore dormancy and sporangium dehiscence.

Three-dimensional ultrastructural study of the anther of Silene latifolia infected with Microbotryum lychnidis-dioicae

When Microbotryum lychnidis-dioicae infects a male Silene latifolia, M. lychnidis-dioicae smut spores develop in the pollen sac instead of pollen. In contrast, when M. lychnidis-dioicae infects a female S. latifolia, the female flowers become male-like, promoting stamen formation. However, it is unclear when and how M. lychnidis-dioicae invades the anther. It is important to investigate not only whether hyphae exist when the apical meristem tissue differentiates into flowers and anthers, but also whether hyphae exist when stamen filaments form. We used Grocott’s methenamine silver stain and lectin stain, which stain chitin in the fungal cell wall, to search for M. lychnidis-dioicae in flower tissues. A few M. lychnidis-dioicae hyphae were observed intercellularly in the center of the connective of vascular bundles at the early anther developmental stage. Subsequently, large numbers of deeply stained M. lychnidis-dioicae hyphae were observed intercellularly in the cells surrounding the pollen sac, as well as in the center of the pollen sac. Hyphae stained with lectin were observed intercellularly in all of the stamen filaments at flower development stages. Hyphae were observed in the peduncle connecting the flower and stem. It is thought that M. lychnidis-dioicae invaded the anther via the stamen filament over a long period. Additionally, in total, 163 sections of connective were obtained, and the cell structure of each anther was colored and subjected to three-dimensional reconstruction. The M. lychnidis-dioicae hyphae observed in the connective were mainly old hyphae with large vacuoles or dead hyphae (S1 Fig). These hyphae branched out, towards the pollen sac, while growing between the cells. We also observed that the host cells that collapsed near the hyphae had thick cell walls and teliospores. Cell wall collapse and cell degeneration were observed only around hyphae with thick cell walls.

Cell Death and Cell Cycle Arrest of Silene latifolia Stamens and Pistils After Microbotryum lychnidis-dioicae Infection

Mechanisms of suppression of pistil primordia in male flowers and of stamen primordia in female flowers differ in diclinous plants. In this study, we investigated how cell death and cell cycle arrest are related to flower organ formation in Silene latifolia. Using in situ hybridization and a TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay, we detected both cell cycle arrest and cell death in suppressed stamens of female flowers and suppressed pistils of male flowers in S. latifolia. In female flowers infected with Microbotryum lychnidis-dioicae, developmental suppression of stamens is released, and cell cycle arrest and cell death do not occur. Smut spores are formed in S. latifolia anthers infected with M. lychnidis-dioicae, followed by cell death in the endothelium, middle layer, tapetal cells and pollen mother cells. Cell death is difficult to detect using a fluorescein isothiocyanate-labeled TUNEL assay due to strong autofluorescence in the anther. We therefore combined a TUNEL assay in an infrared region with transmission electron microscopy to detect cell death in anthers. We show that following infection by M. lychnidis-dioicae, a TUNEL signal was not detected in the endothelium, middle layer or pollen mother cells, and cell death with outflow of cell contents, including the nucleoplast, was observed in tapetal cells.

Comparison of ultrasonographic joint and tendon findings in hands between early, treatment-naïve patients with systemic lupus erythematosus and rheumatoid arthritis

Although both systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) may lead to joint deformity, SLE arthritis is typically non-erosive and often accompanied by Jaccoud's deformity. Therefore, we examined characteristics of joint and tendon lesions in patients with SLE and RA by ultrasonography. Fifteen treatment-naïve SLE patients and 40 treatment-naïve RA patients with joint symptoms were included in this study. The hand joints and related tendons were ultrasonographically examined using grey-scale (GS) and power Doppler (PD). Joint involvement was comparably observed in patients with SLE and RA (80% versus 95%, p = 0.119). However, tendon involvement was more frequent in SLE than in RA (93% versus 65%, p = 0.045), especially in the wrist joints (73% versus 40%, p = 0.037). When we investigated the intensity of US findings, the joint synovitis score (GS + PD) per affected joint was lower in SLE than RA (2.0 versus 2.6, p = 0.019), while tendon inflammation score was not significantly different (2.1 versus 2.2, p = 0.738). Finally, the examination of concordance between joint and tendon involvement in the same finger revealed that joint lesion appeared in only 49% of fingers having tendon involvement in the SLE group, which was significantly less than 74% in the RA group ( p = 0.010). Thus, as compared with RA, SLE arthropathy is characterized by the predominance of tenosynovitis/periextensor tendon inflammation, which is likely to develop independently from joint synovitis.

An ultrahigh volumetric capacitance of squeezable three-dimensional bicontinuous nanoporous graphene

Graphene with a large specific surface area and high conductivity has a large specific capacitance. However, its volumetric capacitance is usually very low because the restacking of 2D graphene sheets leads to the loss of the large ion-accessible surface area. Here we report squeezable bicontinuous nanoporous nitrogen-doped graphene, which is extremely flexible and can tolerate large volume contraction by mechanical compression without the face-to-face restacking occurring. The compressed nanoporous N-doped graphene with a large ion accessible surface area and high conductivity shows an ultrahigh volumetric capacitance of ∼300 F cm^-3 together with excellent cycling stability and high rate performance.

Initial Atomic Motion Immediately Following Femtosecond-Laser Excitation in Phase-Change Materials

Despite the fact that phase-change materials are widely used for data storage, no consensus exists on the unique mechanism of their ultrafast phase change and its accompanied large and rapid optical change. By using the pump-probe observation method combining a femtosecond optical laser and an x-ray free-electron laser, we substantiate experimentally that, in both GeTe and Ge_{2}Sb_{2}Te_{5} crystals, rattling motion of mainly Ge atoms takes place with keeping the off-center position just after femtosecond-optical-laser irradiation, which eventually leads to a higher symmetry or disordered state. This very initial rattling motion in the undistorted lattice can be related to instantaneous optical change due to the loss of resonant bonding that characterizes GeTe-based phase change materials. Based on the amorphous structure derived by first-principles molecular dynamics simulation, we infer a plausible ultrafast amorphization mechanism via nonmelting.

Morphological and Immunohistochemical Features of Cryptosporidium andersoni in Cattle

Light and electron microscopic features and immunohistochemical features of Cryptosporidium andersoni ( C. andersoni) and host reaction in the mucosa were studied. Although the affected cattle demonstrated no apparent clinical signs, a severe infection of C. andersoni was observed in the abomasum. C. andersoni were round in shape, measured 6-8 μm in size and were mainly observed to be freely located in the gastric pits, being attached in occasional cases to the surface of the abomasum epithelium. Frequent inflammatory cells had infiltrated the lamina propria of the affected mucosa, and frequent mitotic figures were observed in epithelial cells at the dilated isthmus. To access the cell kinetics, the number of epithelial cells infected with C. andersoni were counted and compared with noninfected cattle. The number of gastric pit cells in infected cattle was significantly higher than that in the controls. The number of proliferative cells determined by the Ki-67 antigen in C. andersoni infected cattle was also significantly higher than that in the controls. Transmission electron microscopy and scanning electron microscopy revealed that the morphology of the C. andersoni organism was common to those of other Cryptosporidium spp. immunohistochemically, several commercial antibodies against Cryptosporidium spp. showed positive reactions at the wall of these oocysts or parasitophorous vacuoles. This report is possibly the first to discuss the prominent hyperplasia of the abomasum mucosa, as well as morphologic features of C. andersoni in cattle.

Highly efficient lipid production in the green alga Parachlorella kessleri: draft genome and transcriptome endorsed by whole-cell 3D ultrastructure

BACKGROUND

Algae have attracted attention as sustainable producers of lipid-containing biomass for food, animal feed, and for biofuels. Parachlorella kessleri, a unicellular green alga belonging to the class Trebouxiophyceae, achieves very high biomass, lipid, and starch productivity levels. However, further biotechnological exploitation has been hampered by a lack of genomic information.

RESULTS

Here, we sequenced the whole genome and transcriptome, and analyzed the behavior of P. kessleri NIES-2152 under lipid production-inducing conditions. The assembly includes 13,057 protein-coding genes in a 62.5-Mbp nuclear genome. Under conditions of sulfur deprivation, lipid accumulation was correlated with the transcriptomic induction of enzymes involved in sulfur metabolism, triacylglycerol (TAG) synthesis, autophagy, and remodeling of light-harvesting complexes.

CONCLUSIONS

Three-dimensional transmission electron microscopy (3D-TEM) revealed extensive alterations in cellular anatomy accompanying lipid hyperaccumulation. The present 3D-TEM results, together with transcriptomic data support the finding that upregulation of TAG synthesis and autophagy are potential key mediators of the hyperaccumulation of lipids under conditions of nutrient stress.

A novel automated detection system for swallowing sounds during eating and speech under everyday conditions

The wave analysis of swallowing sounds has been receiving attention because the recording process is easy and non-invasive. However, up until now, an expert has been needed to visually examine the entire recorded wave to distinguish swallowing from other sounds. The purpose of this study was to establish a methodology to automatically distinguish the sound of swallowing from sound data recorded during a meal in the presence of everyday ambient sound. Seven healthy participants (mean age: 26·7 ± 1·3 years) participated in this study. A laryngeal microphone and a condenser microphone attached to the nostril were used for simultaneous recording. Recoding took place while participants were taking a meal and talking with a conversational partner. Participants were instructed to step on a foot pedal trigger switch when they swallowed, representing self-enumeration of swallowing, and also to achieve six additional noise-making tasks during the meal in a randomised manner. The automated analysis system correctly detected 342 out of the 352 self-enumerated swallowing events (sensitivity: 97·2%) and 479 out of the 503 semblable wave periods of swallowing (specificity: 95·2%). In this study, the automated detection system for swallowing sounds using a nostril microphone was able to detect the swallowing event with high sensitivity and specificity even under the conditions of daily life, thus showing potential utility in the diagnosis or screening of dysphagic patients in future studies.

Characterization of spontaneous malignant lymphomas in Japanese macaques (Macaca fuscata)

Lymphomas are common spontaneous tumors in nonhuman primates but remain poorly characterized in Japanese macaques (Macaca fuscata). This study examined 5 cases of spontaneous malignant lymphoma in Japanese macaques, focusing on the immunophenotypes and presence of simian lymphocryptoviruses, which are Epstein-Barr virus-related herpesviruses in nonhuman primates. The macaques with lymphoma were 5 to 28 years old, indicating that lymphomas develop over a wide age range. The common macroscopic findings were splenomegaly and enlargement of lymph nodes. Histologic and immunohistochemical analyses revealed that all cases were non-Hodgkin type and exhibited a T-cell phenotype, positive for CD3 but negative for CD20 and CD79α. The lymphomas exhibited diverse cellular morphologies and were subdivided into 3 types according to the World Health Organization classification. These included 3 cases of peripheral T-cell lymphoma, not otherwise specified; 1 case of T-cell prolymphocytic leukemia; and 1 case of an unclassifiable T-cell lymphoma. Positive signals were detected by in situ hybridization in 2 of the 4 examined cases using probes for the Epstein-Barr virus-encoded small RNA (EBER). Furthermore, the presence of M. fuscata lymphocryptovirus 2, a macaque homolog of Epstein-Barr virus, was demonstrated in EBER-positive cases by polymerase chain reaction amplification followed by direct sequencing. Immunohistochemistry using antibody to the Epstein-Barr virus-encoded nuclear antigen 2 was negative, even in the EBER-positive cases. The present study suggests that T-cell lymphoma is more common than B-cell lymphoma in Japanese macaques and that M. fuscata lymphocryptovirus 2 is present in some cases.