LLPS of SQSTM1/p62 and NBR1 as outcomes of lysosomal stress response limits cancer cell metastasis

Liquid droplet has emerged as a flexible intracellular compartment that modulates various cellular processes. Here, we uncover an antimetastatic mechanism governed by the liquid droplets formed through liquid-liquid phase separation (LLPS) of SQSTM1/p62 and neighbor of BRCA1 gene 1 (NBR1). Some of the tyrosine kinase inhibitors (TKIs) initiated lysosomal stress response that promotes the LLPS of p62 and NBR1, resulting in the spreading of p62/NBR1 liquid droplets. Interestingly, in the p62/NBR1 liquid droplet, degradation of RAS-related C3 botulinum toxin substrate 1 was accelerated by cellular inhibitor of apoptosis protein 1, which limits cancer cell motility. Moreover, the antimetastatic activity of the TKIs was completely overridden in p62/NBR1 double knockout cells both in vitro and in vivo. Thus, our results demonstrate a function of the p62/NBR1 liquid droplet as a critical determinant of cancer cell behavior, which may provide insight into both the clinical and biological significance of LLPS.

Allergic disorders and their risk factors in primary Sjögren's syndrome

Objective

This study aimed to evaluate the prevalence of allergic disorders in patients with primary Sjögren's syndrome (pSS), compare it with that of patients with rheumatoid arthritis (RA), and examine the risk factors in patients with pSS.

Methods

We retrospectively examined the records of patients diagnosed with pSS and RA who regularly visited our department between 2010 and 2020. Allergic disorders included drug allergy, food allergy, allergic contact dermatitis (ACD), allergic rhinitis (AR)/allergic conjunctivitis (AC), and asthma.

Results

Patients with pSS (292 patients) had a higher prevalence of food allergy, drug allergy, and AR/AC than those with RA (413 patients). The multivariate analysis revealed that patients with pSS who had drug allergy had a higher prevalence of food allergy, higher eosinophil levels, and higher positivity rates of anti-SS-related antigen A (SSA) antibodies than those without drug allergy; those with food allergy had a higher rate of ACD than those without food allergy and vice versa; those with AR/AC had a higher rate of ACD and asthma and higher eosinophil levels than those without AR/AC; those with asthma had a higher rate of AR/AC than those without asthma.

Conclusions

Patients with pSS had a higher prevalence of allergic disorders than those with RA. Among patients with pSS, the risk factors for drug allergy were food allergy, higher eosinophil levels, and positivity for anti-SSA antibodies, the risk factor for food allergy was ACD and vice versa, the risk factors for AR/AC were ACD, asthma, and high eosinophil levels, and the risk factor for asthma was AR/AC.

Aseptic meningitis as an initial manifestation of primary Sjögren's syndrome

Aseptic meningitis is a rare life-threatening complication of primary Sjögren's syndrome (pSS) and its characteristics and prognosis remain unknown. We present our case of aseptic meningitis associated with pSS and reviewed the published literature to elucidate their characteristics and prognosis. An 84-year-old man was admitted to our hospital for fever and disturbance of consciousness. Acute aseptic meningitis was diagnosed based on the results for cerebrospinal fluid and head imaging tests. As an etiological investigation for his aseptic meningitis, serum anti-SSA and anti-SSB antibodies were found to be positive and the biopsy specimen of his labial salivary gland revealed a lymphocytic sialadenitis, confirming a diagnosis with pSS. Treatment with moderate-dose glucocorticoid completely improved his aseptic meningitis. Relapse of the disease was not observed during his clinical course over 12 months. Our present case and literature review suggest that aseptic meningitis can be an initial manifestation of pSS and treatable by immunosuppressive therapy. Thus, early recognition and treatment initiation are critical to prevent irreversible damage of central nerve system in pSS-associated aseptic meningitis. In aseptic meningitis of unknown origin, pSS should be included in differential diagnoses, and testing for serum anti-SSA and anti-SSB antibodies may be useful as an initial screening.

Risk factors associated with cytomegalovirus reactivation in patients receiving immunosuppressive therapy for rheumatic diseases: a retrospective study

Immunosuppressive treatment is a common cause of cytomegalovirus (CMV) reactivation. However, there is no consensus regarding the risk factors for CMV reactivation in rheumatic diseases. Therefore, this study aimed to elucidate the risk factors associated with CMV reactivation. We retrospectively collected the data of 472 patients with rheumatic diseases whose CMV pp65 antigen (C7-HRP) titer was measured. We divided the patients into those with and those without C7-HRP. We retrospectively collected data on age, sex, primary condition and organ involvement, and blood test results. We also investigated the use of immunosuppressants and the maximum and cumulative doses of prednisolone (PSL). We performed univariate and multivariate analyses to identify risk factors for CMV reactivation. Multivariate analysis showed that higher age (71.2 vs. 64.4 years, p = 0.0022), hypoalbuminemia (2.9 vs. 3.4 g/dL, p = 0.0104), higher creatinine level (1.2 vs. 0.9 mg/dL, p = 0.0026), cyclosporine use (8.2 vs. 3.6%, p = 0.0101), and higher maximum (552.4 vs. 243.3 mg, p < 0.0001) and cumulative (2785.9 vs. 1330.5 mg, p < 0.0001) doses of PSL were associated with CMV reactivation. Older age, hypoalbuminemia, higher creatinine level, cyclosporine use, and higher maximum and cumulative doses of PSL were significant risk factors for CMV reactivation in rheumatic diseases.

Acute encephalitis in primary Sjögren's syndrome: A case report and literature review

Acute encephalitis is an extremely rare condition in primary Sjogren's syndrome (pSS), and its characteristics and prognosis remain unclear. Here, we report the case of pSS presented with acute encephalitis. She was admitted to our hospital for acute disturbance of consciousness. Acute encephalitis was diagnosed based on the results of the cerebrospinal fluid test (the increase of leucocyte counts, proteins, and interleukin-6 levels), magnetic resonance imaging, and single-photon emission computed tomography with 99mTc. The infectious aetiologies and underlying malignancies were excluded. Serum anti-Sjogren's syndrome-related antigen A autoantibody was positive with extremely high titre. The biopsy specimen of her labial salivary gland revealed a focal lymphocytic sialadenitis with a score of grade 4 in the Greenspan grade. She also developed diffuse alveolar haemorrhage during the clinical course. She was diagnosed with pSS complicated with acute encephalitis followed by diffuse alveolar haemorrhage and successfully treated with pulse steroids, high dose of prednisolone and intravenous cyclophosphamide. Our present case and literature review suggest that acute encephalitis associated with pSS can be treatable with the immunosuppressive therapy, and thus early recognition and treatment initiation are important for this life-threatening condition. Thus, pSS should be included in the differential diagnosis of unexplained encephalitis. Notably, our case characteristically showed diffuse alveolar haemorrhage, adding new insights into the pathogenesis of acute encephalitis associated with pSS that capillaritis might be the underlying cause of this condition.

POS1423 CHARACTERISTICS OF CYTOMEGALOVIRUS-POSITIVE VERSUS NEGATIVE, AND CYTOMEGALOVIRUS-TREATED VERSUS UNTREATED PATIENTS DURING IMMUNOSUPPRESSIVE THERAPY FOR RHEUMATIC DISEASES

Background

Immunosuppressive treatment is a common cause of cytomegalovirus (CMV) reactivation.

Objectives

To elucidate the characteristics of CMV-positive and negative patients during the treatment for rheumatic diseases.

Methods

We retrospectively evaluated consecutive patients admitted to our department from January 2006 to October 2021 whose C7-HRP antigen were measured. We collected their age, sex, primary problem and its lesion, and test results within 3 months before C7-HRP measurement. We also investigated the use of immunosuppressants, and maximum and cumulative dose of administered prednisolone within 6 months before C7-HRP measurement. Maximum and cumulative dose of prednisolone contained methylprednisolone pulse, which was converted into prednisolone equivalent. We investigated the characteristics of CMV-positive and negative patients, and those of CMV-positive patients with or without anti-CMV drug use.

Results

Of a total of 472 patients, 85 were positive and 387 were negative for C7-HRP. The average age was 71.2 vs. 64.4 (p=0.0021). Their male-to-female ratio was 20/65 vs. 120/267 (p=0.0290). The following diseases were significantly common among CMV-positive patients: microscopic polyangiitis (21.2% vs. 3.9%, p<0.0001), adult-onset Still’s disease (7.1% vs. 1.3%, p=0.0002), and systemic sclerosis (4.7% vs. 2.1%, p=0.0273). Significantly common comorbidities of CMV-positive patients were interstitial lung disease (35.3% vs. 16.0%, p<0.0001), nephritis (23.5% vs. 11.6%, p=0.0005), peripheral nervous system disorders (11.8% vs. 5.7%, p=0.0070), alveolar hemorrhage (5.9% vs. 0.8%, p=0.0001), and peripheral circulatory disorders (4.7% vs. 1.6%, p=0.0111). Average neutrophil counts (7720 /μL vs. 6440 /μL, p=0.0001), serum creatinine (1.0 mg/dL vs. 0.9 mg/dL, p=0.0104), and hemoglobin A1c (6.3% vs. 5.7%, p=0.0030) were significantly higher among CMV-positive patients, whereas hemoglobin (10.1 g/dL vs. 11.1 g/dL, p<0.0001), lymphocyte counts (820 /μL vs. 1190 /μL, p<0.0001), platelet counts (233000 /μL vs. 259000 /μL, p<0.0001), and serum albumin (2.9 g/dL vs. 3.4 g/dL, p<0.0001) were lower. Higher maximum dose of prednisolone (534.9 mg/day vs. 135.5 mg/day, p<0.0001), intravenous cyclophosphamide (27.1% vs. 11.4%, p<0.0001), rituximab (9.4% vs. 2.1%, p<0.0001), azathioprine (23.5% vs. 14.2%, p=0.0053), cyclosporin (8.2% vs. 3.6%, p=0.0101) were significantly more often used among CMV-positive patients. Average cumulative dose of prednisolone was 3022.6 mg vs. 1408.7 mg (p<0.0001). We also performed multivariate analysis, including the patients’ age, sex, maximum and cumulative dose of prednisolone, and the use of intravenous cyclophosphamide, rituximab, azathioprine, and cyclosporin. Elderly (p=0.0006), female (p=0.0293), high cumulative dose of prednisolone (p=0.0155), and the use of cyclosporin (p=0.0479) were significantly associated with CMV-positivity. Anti-CMV drug was administered to 63.5% of CMV-positive patients. The average age was significantly higher in anti-CMV-drug-treated patients than untreated patients (73.7 vs. 67.1, p=0.0492). The CMV-treated patients had significantly higher neutrophil counts (8540 /μL vs. 6280 /μL, p<0.0001), erythrocyte sedimentation rate (57.6 mm/h vs. 40.5 mm/h, p<0.0001), and C-reactive protein (5.3 mg/dL vs. 2.6 mg/dL, p<0.0001) than the untreated patients while the other data such as complete blood counts and serum chemistry revealed no significant difference. Average maximum dose of prednisolone was significantly higher in CMV-treated patients (617.1 mg/day vs. 391.1 mg/day, p=0.0261) while average cumulative dose of prednisolone and the use of any other immunosuppressants revealed no significant difference.

Conclusion

Intense immunosuppression, especially with higher dose of glucocorticoids, seemed to be the major risk factor of CMV reactivation. These medications may often require anti-CMV therapy.

Disclosure of Interests

None declared

AB0298 THE RISK OF SULPHA ALLERGY IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background

Sulpha drugs have been used such as sulfasalazine for the treatment of rheumatoid arthritis (RA), and trimethoprim-sulfamethoxazole (TMP-SMX) for the treatment or prevention of pneumocystis pneumonia. However, some patients with RA delay treatment because of allergy to sulpha drugs[1]. We reported that 16.7% of RA patients presented drug allergies[2]. It was not clear what is a risk factor for drug allergies in patients with RA.

Objectives

The aim of this study was to evaluate the clinical features with sulpha allergy in patients with RA.

Methods

We prospectively examined consecutive patients diagnosed with RA in our hospital from March 2021 to January 2022. The patients with RA met the EULAR/ACR 2010 criteria. We included patients with RA with other rheumatic diseases. A careful allergic history was obtained from patients with RA and physical examination performed.

The first analysis was performed on patient baseline laboratory data at diagnosis of patients with RA with or without sulpha allergy. Sulpha allergy (rash, angioedema and anaphylaxis after drug exposure) was allergy to sulfasalazine or TMP-SMX. The second analysis was performed on seven types of allergic reactions: (1) drug allergies other than sulpha drugs (rash, angioedema and anaphylaxis after drug exposure), (2) food allergy (rash, angioedema and anaphylaxis after foods exposure), (3) allergic contact dermatitis such as metals, and other cosmetics, (4) seasonal allergic rhinitis and/or conjunctivitis (AR and/or AC), and AR and/or AC associated with house dust, (5) asthma, and (6) atopic dermatitis.

Results

There were 513 patients with RA in our study. In the first analysis, 17 patients with sulpha allergy and 496 patients without sulpha drugs were enrolled (Table 1). The median ages (with supha allergy and without sulpha allergy) were 66.0 and 72.0 years old (p=0.40). Females were 82.3% and 77.0%(p=0.4). The median observation period was 97.0 and 69.0 months (p=0.20). Patients with other rheumatic diseases were 11.6 and 6.8% (p=0.34).

Table 1.

Characteristics of RA patients at diagnosis of RA

With sulpha allergy (n = 17)Without sulpha allergy (n = 496)PFemale83.4%76.9%0.77Age, year, y66.0 (56.0-78.5)72.0 (60.0-80.0)0.40Observation period, m97.0 (45.5-182.0)69.0 (31.0-123.8)0.20Patients with other rheumatic diseases11.8%6.8%0.34ANA-positive patients(>1:80)52.9%28.2%0.052Anti-SSA antibody-positive patients46.2%18.2%0.02RF-positive patients40.0%66.8%0.049

The RA patients with sulpha allergy had higher positivity rate of anti-nuclear antibody (ANA) (>1:80) (52.9%, 28.2%: p=0.052), higher positivity rate of anti–Sjögren’s-syndrome-related antigen A autoantibody (anti-SSA antibody) than those without sulpha allergies (46.2%, 18.2%: p = 0.02) and lower positivity rate of rheumatoid factor(RF) than those without sulpha allergies (40.0%, 66.8%: p = 0.049).

In the second analysis drug allergies other than sulpha allergy were more frequent in patients with sulpha allergy. Drug allergies other than sulpha allergy were such as antibiotics and nonsteroidal anti-inflammatory drugs. There were no significant differences in other allergies.

Conclusion

Among patients with RA, patients with sulpha allergy had higher positivity rate of ANA and anti-SSA antibody, and lower positivity rate of RF than those without sulpha allergy. RA patients with sulpha allergy had a higher prevalence of the other drug allergies than those other than sulpha allergy.

References

[1]Konishi MH et al. Allergic diseases in adult-onset Still’s disease and rheumatoid arthtitis. Arerugi. 2021; 70: 965-975.

[2]Konishi MH et al. Allergic Disorders and Drug Allergies in Primary Sjögren’s Syndrome and Rheumatoid Arthritis. EULAR 2021.

Disclosure of Interests

None declared

Immune-mediated necrotizing myopathy which showed deposition of C5b-9 in the necrotic muscle fibers and was successfully treated with intensive combined therapy with high-dose glucocorticoids, tacrolimus, and intravenous immunoglobulins

Currently, no standard treatment strategy has been established for immune-mediated necrotizing myopathy (IMNM). Here we present a case of IMNM which was successfully treated with intensive combined therapy with high-dose glucocorticoids, tacrolimus, and intravenous immunoglobulins. Her muscle weakness was rapidly progressive and severe so that she became bedridden one week after admission. She was complicated with dysphagia and had serum myogenic enzymes elevation, ventricular diastolic dysfunction, and interstitial lung disease. Serum anti-SRP antibody was positive and her muscle biopsy revealed many necrotic fibers with minimal inflammation. Further histological analysis demonstrated infiltration of phagocytic macrophages with deposition of membrane attack complex (C5b-9) in the necrotic muscle fibers, suggesting activation of complement pathway and macrophages as a pathomechanism of this disease. She was diagnosed as IMNM and was immediately initiated a combination therapy described above, which led to dramatic clinical improvements. Recent studies suggest that intravenous immunoglobulins and tacrolimus can inhibit the activation of complement pathway and macrophages. Our present case suggests that early initiation of intensive combined therapy including intravenous immunoglobulins and tacrolimus might be effective for preventing irreversible muscle damages by disrupting a pathogenic activation of complement and macrophages in IMNM.

Patterns of nesting behaviour and nesting success for green turtles at Raine Island, Australia

To understand how turtles use the nesting habitat at Raine Island across a nesting season, and how the turtles respond to the restoration of the island’s dune systems, we identified 534 nesting events for 39 green turtles Chelonia mydas across 2 breeding seasons using data derived from satellite tags. Tracked turtles laid between 4 and 10 clutches of eggs. Patterns of nesting success varied between individuals, within and between seasons. Nesting success was higher in 2018-19 (57%) than 2017-18 (45%), and in both years, nesting success was lowest between October and early January (<50%). In 2017-18, increased rainfall in January corresponded with increased nesting success (>50%). The density of female turtles ashore was lower in 2018-19, and likely explains higher nesting success in 2018-19 because competition for nest space was lower. In 2017-18, females had more attempts per clutch, and the attempts were around 90 min longer. Consequently, energy required to lay a clutch of eggs in 2017-18 was significantly higher than in 2018-19, highlighting potential costs of lower nesting success rates on reproductive output. The area of beach re-profiled as an intervention in 2014 and 2017 was a nesting hotspot in 2017-18. However, in 2018-19, the area was not used to the same extent, and the nesting hotspot occurred on the north-eastern unaltered beach. Collectively, the tracking of turtles across the whole nesting season enabled us to assess overall beach use and nesting site fidelity of green turtles at Raine Island. Results will aid future planning and management of beach restoration activities at turtle nesting sites.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

Dermatomyositis Which Was Double Positive for Anti-MDA5 and Anti-ARS Antibodies That Was Successfully Treated by Intensive Immunosuppressive Therapy

Myositis-specific autoantibody is associated with the clinical phenotype and prognosis of dermatomyositis. Anti-melanoma differentiation-associated gene 5 (MDA5) and anti-aminoacyl-tRNA synthetase (ARS) antibodies are generally mutually exclusive. We herein present an extremely rare case of dermatomyositis which showed double positivity for anti-MDA5 and anti-ARS antibodies. There have been very few reported cases of double positive anti-MDA5, anti-ARS antibodies. In such cases, the clinical characteristics of each autoantibody can coexist. Thus, we should pay attention to the rapidly progressing features of anti-MDA5 as well as the chronic relapsing features of anti-ARS for the better management of this rare condition.

[ALLERGIC DISEASES IN ADULT-ONSET STILL'S DISEASE AND RHEUMATOID ARTHRITIS]

BACKGROUND

A high prevalence of allergic diseases was found in patients with adult-onset Still's disease (AOSD). However, the relative prevalence is unknown compared with other diseases.

OBJECTIVES

We sought to compare the prevalence of allergic diseases in the control group of patients with rheumatoid arthritis (RA).

METHODS

We retrospectively examined consecutive patients diagnosed with AOSD or RA in our hospital from 2010 to 2020. The patients with AOSD met the preliminary criteria for classification of AOSD. The patients with RA met the EULAR/ACR 2010 criteria. We included patients with RA without other rheumatic diseases. The analysis was performed on six types of allergic reactions: food allergy, drug allergy, allergic contact dermatitis, allergic rhinitis and/or allergic conjunctivitis, and asthma.

RESULTS

Twenty-four patients with AOSD and 409 patients with RA were enrolled. The median ages (AOSD, RA) were 46.6, 68.2 years old. Females were 83.3%, 78.0%. Fifty% of AOSD patients and 34.5% of RA patients presented at least one type of allergic diseases (p = 0.12). These included food allergy (4.2%, 6.4%: p = 1.0), drug allergy (37.5%, 16.6%: p = 0.02), allergic rhinitis/allergic conjunctivitis (25.0%, 8.6%: p = 0.02), contact dermatitis (4.2%, 4.4%: p = 1.0), and asthma (4.2%, 5.9%: p = 1.0).

CONCLUSION

Patients with AOSD had a higher prevalence of drug allergy, and allergic rhinitis/allergic conjunctivitis than patients with RA.

The E3 Ubiquitin-Protein Ligase RNF4 Promotes TNF-α-Induced Cell Death Triggered by RIPK1

Receptor-interacting protein kinase 1 (RIPK1) is a key component of the tumor necrosis factor (TNF) receptor signaling complex that regulates both pro- and anti-apoptotic signaling. The reciprocal functions of RIPK1 in TNF signaling are determined by the state of the posttranslational modifications (PTMs) of RIPK1. However, the underlying mechanisms associated with the PTMs of RIPK1 are unclear. In this study, we found that RING finger protein 4 (RNF4), a RING finger E3 ubiquitin ligase, is required for the RIPK1 autophosphorylation and subsequent cell death. It has been reported that RNF4 negatively regulates TNF-α-induced activation of the nuclear factor-κB (NF-κB) through downregulation of transforming growth factor β-activated kinase 1 (TAK1) activity, indicating the possibility that RNF4-mediated TAK1 suppression results in enhanced sensitivity to cell death. However, interestingly, RNF4 was needed to induce RIPK1-mediated cell death even in the absence of TAK1, suggesting that RNF4 can promote RIPK1-mediated cell death without suppressing the TAK1 activity. Thus, these observations reveal the existence of a novel mechanism whereby RNF4 promotes the autophosphorylation of RIPK1, which provides a novel insight into the molecular basis for the PTMs of RIPK1.

Early restenosis and late catch-up phenomenon after newer biodegradable- and durable-polymer drug-eluting stent implantations

Background

It is yet to be known whether mechanisms underlying restenosis in newer-generation durable-polymer (DP) and biodegradable-polymer (BP) drug-eluting stents (DES) are different.

Purpose

This study aims to assess the incidences and predictors of early restenosis and late catch-up phenomenon after newer-generation durable-polymer (DP) and biodegradable-polymer (BP) DES.

Methods

Between 2010 and 2017, 13858 lesions in 6350 patients were treated with DES (4393 BP-DES, 9465 DP-DES). The early-term (within 1 year) and late-term (from 1 to 2 years) follow-up angiographies were scheduled. Late catch-up phenomenon was defined as in-stent restenosis (ISR) in lesions that evaded ISR within 1 year after stent implantation. ISR was defined as angiographic restenosis of more than 50%.

Results

The mean patient age was 71 years, and 76.7% were male. Early-term angiographies were performed in 10955 lesions (79.0%). Of those without early-term ISR, late-term angiographies were performed in 7771 lesions (56.1%). The incidences of mid-term restenosis and late catch-up phenomenon were 6.6% and 3.9%, respectively.

In the multivariate regression analyses, history of diabetes, hemodialysis and previous PCI were independent predictors of both early restenosis and late catch-up phenomenon. Also, some lesion characteristics such as chronic total occlusion, right coronary artery ostial lesion, small vessel (defined as reference diameter &lt;2.5mm), long lesion (defined as lesion length &gt;30mm) and treatment of ISR lesion were independent predictors of both early restenosis and late catch-up phenomenon.

Bifurcation lesion and heavily calcified lesion treated with rotablator were independent risk of early restenosis. Bypass graft lesion was an independent predictor of late catch-up phenomenon.

Early restenosis was observed less frequently in DP-DES than in BP-DES (6.3% versus 7.4%, P=0.012). On the contrary, late catch-up phenomenon was observed more frequently in DP-DES than in BP-DES (4.3% versus 2.9%, P=0.026).

Conclusions

Some lesion characteristics were independent predictors of early restenosis and late catch-up phenomenon after newer-generation DES implantation. The deployment of BP-DES resulted in more early restenosis and less late catch-up phenomenon compared to that of DP-DES.

Early Restenosis and Late Catch-Up

Funding Acknowledgement

Type of funding source: None

Clinical features and prognosis of acute myocardial infarction due to coronary artery embolism

Background

Coronary artery embolism (CE) is one of the important causes of acute coronary syndrome (ACS). The feature of CE is that angiographic evidence of coronary artery embolism and thrombosis without atherosclerotic components. However, the prevalence of CE remains unknown because of the diffifulty to diagnose in the acute settings. A recent retrospective analysis suggested that up to 3% of ACS cases may result from CE.

Purpose

The aim of this study was to elucidate the prevalence, clinical features and long-term outcomes including all-cause and cardiac death.

Methods

We analysed the consecutive 2695 patients with first AMI performed coronary intervention between January 2004 and July 2017. CE was diagnosed by clinical histories and angiographic findings. We retrospectively evaluated the clinical and lesion characteristics and outcomes including all-cause and cardiac death.

Results

The prevalence of CE was 2.0% (n=55; CE group and n=2640; non-CE group), including 8 (15%) patients with multivessel CE. The CE group had higher average age (70.8±14.9 vs. 68.4±12.6, p&lt;0.01), prevalence of female (54% vs. 27%, p&lt;0.01), lower prevalence of smoking (34% vs. 62%, p&lt;0.01). The common causes with CE were atrial fibrillation (47%), and malignant tumor (9%), and cardiomyopathy (5%), and patent foramen ovale (4%). Only 20% of patients with CE were treated with anti-coagulant therapy. The rate of distal infarction site (defined as #4, #8, #14–15) was significantly higher in CE group than non-CE group (54.0% vs. 4.9%, p&lt;0.01). During median follow-up of 53.6 [32.6–77.3] months, CE and thromboembolism recurred in 5 patients (CE: 1 patient, stroke 4 patients). The 4-year incidence of all-cause death was significantly higher in the CE group, but cardiac death was not significantly different between the groups (28.8% vs. 14.8%, p=0.03; 12.8% vs. 5.1%, p=0.11).

Conclusion

Compared with non-CE group, the prevalence of distal infarction site was significantly higher in the CE group, and the incidence of cardiac death is not significantly different.

Funding Acknowledgement

Type of funding source: None

Risk stratification based on academic research consortium high bleeding risk criteria for long-term bleeding event after everolimus-eluting stent implantation

Background

Recently, the Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria has been suggested as the standard definition of HBR.

Purpose

We aimed to investigate the risk stratification based on ARC-HBR Criteria for long-term bleeding event after everolimus-eluting stent implantation

Methods

The study population comprised 1193 patients treated with EES without in-hospital event between 2010 and 2011. Individual ARC-HBR criteria was retrospectively assessed. Major bleeding were defined as the occurrence of a Bleeding Academic Research Consortium type 3 or 5 bleeding event. The mean follow-up period was 2996±433 days.

Results

There were 656 patients (55.0%) in HBR-groups. Cumulative incidence of major bleeding was significantly higher in HBR-group (8.1% vs 3.4% at 4 year, and 16.2% vs 5.7% at 8 year, P&lt;0.001). Cumulative rate of major bleeding tend to be higher as the number of ARC-HBR criteria increased (≥2 Majors: 24.3%, 1 Major: 17.0%, ≥2 Minors:11.7%, and Non-HBR: 5.7%, P&lt;0.001).

Conclusion

ARC-HBR criteria successfully stratified the long-term bleeding risk after drug-eluting stent implantation in real-world practice.

Funding Acknowledgement

Type of funding source: None

Pro-apoptotic functions of TRAF2 in p53-mediated apoptosis induced by cisplatin

Tumor necrosis factor receptor-associated factor 2 (TRAF2) is an essential component of tumor necrosis factor-α (TNF-α) signaling that regulates nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) pathways, and compelling evidence has demonstrated that TRAF2 suppresses TNF-α-induced cytotoxicity. On the other hand, it has been reported that oxidative stress-induced cytotoxicity is potentiated by TRAF2, indicating that TRAF2 both positively and negatively regulates stress-induced cytotoxicity in a context-specific manner. However, the causal role of TRAF2 in DNA damage response (DDR) remains to be explored. In this study, we assessed the function of TRAF2 in DDR induced by cisplatin, a representative DNA-damaging agent, and found that TRAF2 exerts pro-apoptotic activity through p53-dependent mechanisms at least in human fibrosarcoma cell line HT1080. TRAF2 deficient cells exhibit significant resistance to cell death induced by cisplatin, accompanied by the reduction of both p53 protein level and caspase-3 activation. Moreover, cisplatin-induced JNK activation was attenuated in TRAF2-deficient cells, and pharmacological inhibition of JNK signaling suppressed p53 stabilization. These results suggest that TRAF2 promotes p53-dependent apoptosis by activating the JNK signaling cascade in HT1080 cells. Thus, our data demonstrate a novel function of TRAF2 in cisplatin-induced DDR as a pro-apoptotic protein.

A synthetic synaptic organizer protein restores glutamatergic neuronal circuits

Neuronal synapses undergo structural and functional changes throughout life, which are essential for nervous system physiology. However, these changes may also perturb the excitatory-inhibitory neurotransmission balance and trigger neuropsychiatric and neurological disorders. Molecular tools to restore this balance are highly desirable. Here, we designed and characterized CPTX, a synthetic synaptic organizer combining structural elements from cerebellin-1 and neuronal pentraxin-1. CPTX can interact with presynaptic neurexins and postsynaptic AMPA-type ionotropic glutamate receptors and induced the formation of excitatory synapses both in vitro and in vivo. CPTX restored synaptic functions, motor coordination, spatial and contextual memories, and locomotion in mouse models for cerebellar ataxia, Alzheimer's disease, and spinal cord injury, respectively. Thus, CPTX represents a prototype for structure-guided biologics that can efficiently repair or remodel neuronal circuits.

An artificial impact on the asteroid (162173) Ryugu formed a crater in the gravity-dominated regime

The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. The impact produced an artificial crater with a diameter >10 meters, which has a semicircular shape, an elevated rim, and a central pit. Images of the impact and resulting ejecta were recorded by the Deployable CAMera 3 for >8 minutes, showing the growth of an ejecta curtain (the outer edge of the ejecta) and deposition of ejecta onto the surface. The ejecta curtain was asymmetric and heterogeneous and it never fully detached from the surface. The crater formed in the gravity-dominated regime; in other words, crater growth was limited by gravity not surface strength. We discuss implications for Ryugu's surface age.

P1307 An echocardiographic observation over the disappearing process of the prosthetic valve thrombus caused by the inflammatory hypercoagulability; a case report

Background

Whenever fever and inflammatory reaction continue for a while in the patients with a prosthetic valve, than usual, we must keep infective endocarditis in mind. On the other hand, inflammation and thrombosis are well known to coexist often. There are several reports of thrombotic valves associated with inflammation-activated hypercoagulability. Furthermore, C-reactive protein (CRP) has been reported to imply an increased risk of thrombus especially in the presence of an injury on the prosthetic valve.

Case report

We report a case of a 70-year-old male with a leaflet thrombus on the bioprosthetic aortic valve. He suffered from fever, and symptoms of heart failure and was hospitalized for treatment. Blood tests presented that white blood cell count was 4900/μL (neutrophil 81.1%) and CRP 10.82 mg/dL. Infectious endocarditis (IE) was suspected. Transthoracic echocardiography (TTE) was per-formed, however, vegetation and abscess were not found. Noteworthily, the bioprosthetic valve leaflet on the right coronary cusp showed thickening and opening dysfunction (Figure A, parasternal short axis). Mean pressure gradient (mPG) through the aortic valve was 15mmHg and peak velocity (Vmax) 2.7m/s. Blood culture was negative, and his body temperature and CRP were improved by empirical antibiotic administration. The anticoagulation therapy with warfarin was started, he was discharged from the hospital and followed up in the outpatient clinic. TTE after the initiation of anticoagulation therapy, did not reveal any more dysfunction on the bioprosthetic valve (mPG: 9mmHg, Vmax: 2.2m/s) (Figure B, parasternal short axis). The diagnostic and therapeutic process of this case implied success. The opening-dysfunction of prosthetic valve leaflets was reversible and therefore, we concluded that the thickening of the prosthetic valve could be attributed to thrombus adhesion. Computed Tomography (CT) was not performed because he suffered from chronic kidney disease.

Conclusion

Surely, CT is very useful for the evaluation of thrombotic valves in the patients in whom it is permissible to use contrast agent. However, we could successfully evaluate the recovery process of leaflet thrombosis by echocardiography because of a difficult reason of CT use in this case. The prolongation of inflammatory reaction in the patients with a prosthetic valve should keep IE in mind in everyday life. Even if the findings of bacterial infection are obscure, it is more and more important to observe carefully the change of leaflets, whenever an open-dysfunction and a thrombus adhesion of the prosthetic valves exist.

Abstract P1307 Figure.

P702 An unusual echocardiographic finding of protrusive vegetation caused by perivalvular abscess perforation into the left atrium

Background

It is well-known that Infective endocarditis (IE) caused by S. aureus progresses rapidly and is highly destructive. The most often abscess formation after aortic valve replacement (AVR) is the mitral-aortic intervalvular fibrosa (MAIVF). It is difficult to cure MAIVF radically once infection occurs, and then the abscess tends to spread. After abscess formation is once established, IE tends to be widespread, the prognosis is definitely poor unless surgical repairment is executed, and then an emergency surgery is essential and unavoidable for complete cure. We report an unusual case of aortic valve abscess with perforation of vegetation into the left atrium after aortic valve replacement.

Case report

A 77-year-old man underwent the bioprosthetic AVR for aortic valve stenosis one month ago. On the 9th day after discharge, he visited the hospital for the follow-up. At the time, the body temperature was 36.6 ° C, the blood pressure 133/50 mmHg, white blood cell count 10500/μL, and C-reactive protein 3.31 mg/dL. Transthoracic echocardiography (TTE) demonstrated the perivalvular abscesses on the prosthetic aortic valve and mass structures attached to the MAIVF in the left atrium (Figure A, C). He was hospitalized again and had an emergency re-operation. Intraoperative transesophageal echocardiography (TEE) showed a perivalvular abscess on the prosthetic valve, and a high-intensity structure (vegetation like) protruding from the Valsalva Sinus into the left atrium of the MAIVF (Figure B, D). Surgical findings did not reveal any wart on the native valve itself. One-third of the annulus was disrupted. The subvalvular tissue all around was abscessed. Notably, the abscess cavity between NCC and LCC reached MAIVF of the anterior mitral leaflet, and the structure projecting to the left atrium was vegetation. In this case, TTE pointed out a perivalvular abscess of the aortic valve, IE was suspected at the time of outpatient visit at an early stage after discharge, and the spread of inflammation was observed with a high speed beyond the expectation at the time of operation.

Conclusion

Early after the operation, TTE revealed a mass was protruded into the left atrium. Generally, vegetation is soft and flexible in itself. However, in this case, the vegetation was less mobile, and for that reason, abscesses or tumors were suspected. TEE enabled us to obtain anatomically more detailed information and to foresee the left atrial wall repairment at the time of reoperation. We reported an unusual case of IE with solid vegetation attached to the wall and difficult to diagnose.

Abstract P702 Figure.

P248 Changes of atrial septum defect caused by posture during three-dimensional transesophageal echocardiography ( a case of Platypnea-orthodeoxia syndrome)

Background

Platypnea-Orthodeoxia syndrome (POS) is a rare phenomenon which is characterized postural hypoxia due to the intracardiac shunt from right to left through a patent foramen ovale, an atrial septal defect or a pulmonary arteriovenous malformation. POS is often underestimated because the hypoxia by postural change is difficult to be detected. We evaluated three-dimensional transesophageal echocardiography (TEE) to diagnose POS in an elderly patient.

Case report

A 84-year-old woman suffered from repetitive syncope for several years. She undertook twelve leads electrocardiogram (ECG), screening transthoracic echocardiography (TTE), twenty-four hours ECG and treadmill stress ECG, however, the cause of syncope was not identified. After another syncope event happened, she was transferred to the emergency room. Then, the hypoxia caused by sitting position was pointed out for the first time.

Her hypoxia was improved by supine position and oxygen administration. TTE demonstrated no right heart enlargement. Shunt flow was suspected on her atrial septum; however, it was difficult to reveal it by TTE because of her obesity. Therefore, she underwent intravenous saline injection test. In the decubitus position, an intravenous injection of saline under Valsalva maneuver revealed the shunt flow from the right atrium to the left atrium. Her arterial oxygen saturation (SpO2) was 95%. In the sitting position, a visible shunt flow was observed, then her SpO2 dropped to 85%. By TEE, the shunt hole was found in the oval fossa of the atrial septum. TEE was evaluated by different positions. The atrial defect hole became larger in the sitting position (area 1.05cm2) than in the supine position (area 0.43cm2). As a result, the postural change to sitting revealed Platypnea-Orthodeoxia syndrome associated with ASD. The pulmonary blood flow/systemic blood flow ratio (Qp/Qs) was estimated at 1.6. After surgical ASD closure, she was discharged without any symptoms.

Conclusion

Unclearness of TTE and the absence of a right heart overload may lead to misdiagnosis of POS. If a syncope patient caused hypoxia in the only sitting position, detailed echocardiography should be needed to rule out a diagnosis of POS. This is considerably valuable case of three-dimensional TEE confirmed the changes of ASD size by postural change.

Abstract P248 Figure.

P1472 Concealed thrombus in a 12-year-old boy diagnosed by disappearance of intricate comb-like pectinate muscle form in the left atrial appendage

Background

As previously known, patients with prolonged atrial fibrillation often have atrial thrombus. However, in children, cardiogenic embolism due to atrial fibrillation is rare. Also, the diagnosis of residual thrombus in the left atrial appendage is sometimes difficult even by transesophageal echocardiography (TEE). We have obtained a meaningful comparison between TEE findings and surgical specimen of bilateral atrial appendage.

Case report

A 12-year-old boy admitted to the nearby hospital, because of sudden onset of right-side hemiplegia. Till then, he was born at normal weight and grew up without any problem. The electrocardiogram indicated atrial fibrillation. He was transferred to the pediatric cardiology department of a hospital with higher function for the treatment of cardiogenic thromboembolism.

After 72 hours from the onset of first thromboembolism, a new embolic event happened in his left brachial artery. The contrast-enhanced computed tomography (CT) showed thrombus of bilateral atrium and coronary sinus. Consequently, residual thrombus led to the potential risk of additional embolization. Therefore, catheter cerebral thrombectomy was performed, and then surgical thrombectomy for the bilateral atrium was planned. Preoperative CT showed thrombus in the left atrial appendage (LAA). However, intraoperative TEE showed no obvious thrombus in the LAA. Intricate pectinate muscle formation in the left atrial appendage almost disappeared (figure1A), which suspected remaining thrombus. In addition, massive thrombus was seen in the right atrium and coronary sinus. Coronary sinus thrombus was removed as far as possible, and bilateral atrial appendage resection and myocardial biopsy were performed. Simultaneously, modified-Maze was also done. Heart rhythm returned into sinus rhythm after surgery. Pathological findings did not show specific findings of myocarditis or pericarditis.

Until now, the cause of thrombotic factors has not been fully clarified. Although the time of onset is unknown, probably, heart failure was triggered by atrial fibrillation, and consequently thromboembolism occurred. In the resected left atrial appendage, small thrombus remained among pectinate muscle (figure1B); therefore, postoperative anticoagulation should be needed.

Conclusion

We experienced a boy with thrombus in bilateral atrial appendages. In the resected left atrial appendage, multiple small thrombi remained in the pectinate muscle. From our experience, the disappearance of comb-like form in pectinate muscle by TEE suspects the residual thrombus, especially in the case of cardiogenic embolism.

Abstract P1472 Figure.

P2693Late catch-up phenomenon and late-term target lesion revascularization of two-stenting for coronary bifurcation lesions between first and second generation drug-eluting stents

Background

The second generation drug-eluting stent (G2-DES) has been reported as superior to the first generation drug-eluting stent (G1-DES) in mid-term outcomes. However, the late-term outcomes between G1-DES and G2-DES in two-stenting for coronary bifurcation lesions are not well studied.

Purpose

To evaluate the late catch-up phenomenon and late-term target lesion revascularization (TLR) of two-stenting for coronary bifurcation lesions between G1-DES and G2-DES.

Methods

This study included 1133 lesions in 1089 patients undergoing drug eluting stent implantation with two stenting from 2004 to 2016. These consisted of 496 G1-DES implanted lesions and 637 G2-DES implanted lesions. Late-term follow-up angiography was performed without in-stent restenosis (ISR) and TLR at mid-term follow-up in 582 lesions (242 G1-DES lesions and 340 G2-DES lesions). ISR was defined as more than 50% restenosis. Late catch-up phenomenon was defined as ISR without ISR within 1 year following index stent implantation. Late-term TLR was defined as from 1 to 5 year TLR. Bifurcation lesions were defined as the main branch ranging from the proximal stem to the distal main branch with boundaries defined by 5 mm proximal and distal to the stent-implanted area, and the side branch ranging from the bifurcation carina to the distal side branch with boundaries defined by the carina and 5 mm distal to the stent-implanted area.

Results

The median follow-up duration was 5.1 years (the first and third quarters, 3.2 and 7.1 years). The late-catch up phenomenon rate significantly differed between the G1-DES and G2-DES groups (16.9% vs 8.4%, p=0.001). A significant difference in late catch-up between the same two groups was also observed in bifurcation lesions of the main branch (5.0% vs 0.6%, p=0.001) and side branch (10.3% vs 5.6%, p=0.033), respectively. The 5-year cumulative rates also differed between the two groups in TLR (8.2% vs 3.7% log-rank p=0.001), and late-term TLR (7.0% vs 3.6% log-rank p=0.001).

Conclusion

Two-stenting using G2-DES, compared with G1-DES, significantly reduced late-term restenosis and TLR. The restenosis rate in bifurcation area may be associated with differences between two groups in late-term outcome.

P5614The association between tissue morphology assessed with optical coherence tomography and mid and late-term results after percutaneous coronary intervention for in-stent restenosis lesions

Background

It was reported that tissue morphology of in-stent restenosis (ISR) lesions assessed with optical coherence tomography (OCT) had an effect on midterm results including ISR and target lesion revascularization (TLR) rates after percutaneous coronary intervention (PCI). However, little was known about the association between tissue morphology assessed with OCT and late-term results.

Methods

We performed PCI treated with paclitaxel coated balloon (PCB) or drug-eluting stent (DES) for 452 ISR lesions (260 lesions with fibrous plaque and 192 lesions with lipid-laden plaque) using OCT between May 2008 and July 2016. Six- to eight-month (midterm) angiographic follow-up was performed on 422 of the 452 ISR lesions (follow-up rate: 93.4%). Furthermore, eighteen- to twenty-month (late-term) angiographic follow-up was performed on 337 of the 361 ISR lesions (follow-up rate: 93.4%) which were free from midterm TLR. We examined the association between tissue morphology, midterm-results and late-term results including ISR and TLR rates. Fibrous plaque was defined as homogeneous, signal-rich regions with low attenuation. Lipid-laden plaque was defined as diffuse border, signal poor regions with high attenuation.

Results

The patients were 353 men and 69 women, and the mean age was 68.8±9.6 years. PCI were performed with PCB in 285 lesions (PCB group) and DES in 137 lesions (DES group). The figure shows the angiographic midterm results of the 422 lesions and late-term results of the 337 lesions with respect to each tissue morphology and each PCI device. There was no difference in ISR and TLR rates of lesions with both fibrous and lipid-laden plaque at midterm between the two groups. ISR and TLR rates of lesions with lipid-laden plaque at late-term were significantly higher in the PCB group than in the DES group, while there was no difference in ISR and TLR rates of lesions with fibrous plaque at late-term between two groups.

Figure 1

Conclusion

Tissue morphology of ISR lesions might have an impact on outcomes after PCI. Morphological assessment of ISR tissue using OCT might suggest favorable types of PCI for ISR lesions.

P1628Angiopoietin-like protein (Angptl) 2 secreted from epicardial adipose tissue induces atrial myocardial fibrosis

Background

Using excised human left atrial appendage samples, we previously demonstrated that epicardial adipose tissue (EAT) are highly associated with atrial myocardial fibrosis as a substrate of atrial fibrillation (AF). We also reported the relationship between Angptl2 in EAT and atrial fibrosis. However, the mechanism is not clear. The purpose is to clarify the mechanisms underlying the effect of EAT on the atrial myocardium.

Methods

Human peri-left atrial EAT and abdominal subcutaneous adipose tissue (SAT) samples were obtained from 6 cases (2 females, 70.2±13.2 years). 50 mg of EAT and SAT were quickly washed with PBS and centrifuged 1min at 1200rpm. After 3 times this procedures, adipose tissues were cultured in DMEM F12 medium with Fetal bovine Serum (FBS) overnight.

After pre-incubation, EAT and SAT tissues were washed and centrifuge d three times and cultured in medium without FBS for 24hours. Finally, we collected oozed medium (conditioned medium) and used for experiments.

Concentrations of Angptl2 in conditioned medium were measured by ELISA.

To study the effects of conditioned medium, we used “organo-culture” system. Isolated atrium from 8week old male Sprague-Dawley rats were placed on the porous membrane with the endothelial face toward the membrane. After that, loading medium (conditioned medium:culture medium = 1:4), culture medium (control), or recombinant Angptl2 were dropped onto the epicardial face of the atrium once a day and incubated for 7 days (37°C, 5% CO2).

Then, histological and immunohistochemical analysis were performed. We also performed quantitative reverse transcription–polymerase chain reaction (RT–PCR) analysis.

Next, we isolated and cultured neonatal rat fibroblast and loaded Angptl2 for 24 hours.After collected these cells, we performed western blotting analysis.

Results

Atria organo-culture incubated for 7 days with conditioned medium showed global fibrosis. At epicardial side, fibrotic area of EAT group was significantly greater compared to that of SAT and control group (P<0.05).

mRNA of Col1a1, col3a1 and TGFβ1 were significantly increased in EAT group compared with the SAT and control group.

And, the concentration of conditioned medium created from EAT was significant higher than that from SAT (P<0.05).

Then, we dropped 500 ng/ml of recombinant Angptl2 onto the rat atria. Fibrotic area of Angptl22 group significantly greater than that of control with increasing number of α-SMA positive cells, and mRNA of col3a1 and TGFβ1 were significantly increased in Angptl2 group compared with control group.

In cultured fibroblasts, α-SMA and p-ERK expression were increased in Angptl2 group measured by western blotting analysis.

Conclusions

Our results demonstrated that EAT rather than SAT induces atrial myocardial fibrosis. There is a possibility that Angptl2 effused from EAT plays a part in atrial fibrosis thought EAT paracrine effect.

Acknowledgement/Funding

ONO PHARMACEUTICAL CO

Hayabusa2 arrives at the carbonaceous asteroid 162173 Ryugu-A spinning top-shaped rubble pile

The Hayabusa2 spacecraft arrived at the near-Earth carbonaceous asteroid 162173 Ryugu in 2018. We present Hayabusa2 observations of Ryugu's shape, mass, and geomorphology. Ryugu has an oblate "spinning top" shape, with a prominent circular equatorial ridge. Its bulk density, 1.19 ± 0.02 grams per cubic centimeter, indicates a high-porosity (>50%) interior. Large surface boulders suggest a rubble-pile structure. Surface slope analysis shows Ryugu's shape may have been produced from having once spun at twice the current rate. Coupled with the observed global material homogeneity, this suggests that Ryugu was reshaped by centrifugally induced deformation during a period of rapid rotation. From these remote-sensing investigations, we identified a suitable sample collection site on the equatorial ridge.

The geomorphology, color, and thermal properties of Ryugu: Implications for parent-body processes

The near-Earth carbonaceous asteroid 162173 Ryugu is thought to have been produced from a parent body that contained water ice and organic molecules. The Hayabusa2 spacecraft has obtained global multicolor images of Ryugu. Geomorphological features present include a circum-equatorial ridge, east-west dichotomy, high boulder abundances across the entire surface, and impact craters. Age estimates from the craters indicate a resurfacing age of [Formula: see text] years for the top 1-meter layer. Ryugu is among the darkest known bodies in the Solar System. The high abundance and spectral properties of boulders are consistent with moderately dehydrated materials, analogous to thermally metamorphosed meteorites found on Earth. The general uniformity in color across Ryugu's surface supports partial dehydration due to internal heating of the asteroid's parent body.

A Case of Feline T-cell Lymphoma with Tropism for Striated Muscle and Peripheral Nerve

An 11-year-old female American shorthair cat was presented with a 3-month history of hindlimb ataxia and knuckling of the left forelimb. Clinical abnormalities included weight loss, hyperaesthesia of the neck and back, cardiac murmur and systemic muscle atrophy. The cat died 10 days after the initial presentation and a necropsy examination was performed. Grossly, extensive pale lesions were seen in the wall of the left ventricle and the septum of the heart. There were no detectable masses in the heart, skeletal muscles or peripheral nerves. Histopathological examination revealed diffuse, extensive infiltration of atypical lymphoid cells in the heart; the cardiac muscles were markedly degenerate and atrophic and were replaced by the neoplastic cells. Neoplastic cells with similar morphology were seen in all specimens of the skeletal muscles and peripheral nerves. Clonality analysis of the paraffin wax-embedded heart tissue revealed a monoclonal rearrangement of the gene encoding the T-cell receptor γ chain. Based on these findings, the case was diagnosed as T-cell lymphoma with tropism for striated muscle and peripheral nerve.

Strength and Viscosity Effects on Perturbed Shock Front Stability in Metals

Computational modeling and experimental measurements on metal samples subject to a laser-driven, ablative Richtmyer-Meshkov instability showed differences between viscosity and strength effects. In particular, numerical and analytical solutions, coupled with measurements of fed-through perturbations, generated by perturbed shock fronts onto initially flat surfaces, show promise as a validation method for models of deviatoric response in the postshocked material. Analysis shows that measurements of shock perturbation amplitudes at low sample thickness-to-wavelength ratios are not enough to differentiate between strength and viscosity effects, but that surface displacement data of the fed-through perturbations appears to resolve the ambiguity. Additionally, analytical and numerical results show shock front perturbation evolution dependence on initial perturbation amplitude and wavelength is significantly different in viscous and materials with strength, suggesting simple experimental geometry changes should provide data supporting one model or the other.

Trapping of excess energy in a nano-layered microenvironment to promote chemical reactions

Nano-layered hybrid compounds composed of a polyfluoroalkyl azobenzene surfactant (abbreviated as C3F-Azo-C6H) and layered inorganic nanosheets undergo three-dimensional morphological changes such as reversible shrinkage and expansion of interlayer spaces, and nanosheet sliding by photo-irradiation. Previously, we have investigated the photoreactivity of C3F-Azo-C6H/clay nano-layered hybrids in various microenvironments and found a remarkable enhancement in the photoreactivity for the cis-trans photo-isomerization reaction (Φ_cis-trans = 1.9). In this paper, nanosecond and microsecond dynamics of trans-C3F-Azo-C6H and its assembly in various microenvironments have been studied by laser flash photolysis to get deeper insight into the extraordinary reactivity of the molecular assembly in the nano-layered microenvironment. In solution, the molecular trans-C3F-Azo-C6H exhibited only a depletion of the trans-form of azobenzene upon the laser pulse excitation. On the other hand, in the case of the C3F-Azo-C6H/clay hybrid film, the depletion of the trans-form was drastically recovered in three steps on nano- and microsecond timescales. This indicates that the once reacted C3F-Azo-C6H molecule (cis-C3F-Azo-C6H) was reverted back to the trans-form after the laser pulse. It is considered that the excess energy provided by the photo-excitation, which is immediately dissipated to the surrounding media through the intermolecular vibrational modes in solution, is trapped in the nano-layered microenvironment to thermally revert the cis-form back to the trans-form. Conversely, in the case of cis-trans isomerization of the C3F-Azo-C6H/clay hybrid film upon photo-irradiation, the reactivity would be much enhanced by the additional contribution of the thermal excess energy efficiently trapped in the nano-layered microenvironment. As compared with the hydrocarbon analogue (C3H-Azo-C6H), the subsequent recovery was very much enhanced in the C3F-Azo-C6H/clay film. The polyfluoroalkyl part of the surfactant layer plays a key role in the retarded dissipation of the excess energy by photo-excitation, which might be coupled with the three-dimensional morphological motion with efficient isomerization reactions.