Utility of allogeneic stem cell transplantation for adult Ph+ALL with complete molecular remission

This study aimed to investigate the usefulness of allogeneic stem cell transplantation (allo-SCT) for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) in the first complete remission (CR1) with complete molecular remission (CMR). We compared the outcomes between Ph+ALL patients who did or did not undergo allo-SCT in CR1. We included patients enrolled in the prospective clinical studies in the tyrosine kinase inhibitor era conducted by the Japan Adult Leukemia Study Group, who achieved CMR within 3 months. A total of 147 patients (allo-SCT: 101; non-SCT: 46) were eligible for this analysis. In the multivariate analyses, allo-SCT was significantly associated with both superior overall survival (OS) (adjusted hazard ratio (aHR): 0.54; 95% CI: 0.30-0.97; p = .04) and relapse-free survival (RFS) (aHR: 0.21; 95% CI: 0.12-0.38; p < .001). The 5-year adjusted OS and RFS were 73% and 70% in the allo-SCT cohort, whereas they were 50% and 20% in the non-SCT cohort. Despite the higher non-relapse mortality (aHR: 3.49; 95% CI: 1.17-10.4; p = .03), allo-SCT was significantly associated with a lower relapse rate (aHR: 0.10; 95% CI: 0.05-0.20; p < .001). In addition, allo-SCT was also associated with superior graft-versus-host disease-free, relapse-free survival (aHR: 0.43; 95% CI: 0.25-0.74; p = .002). Propensity score-matched analyses confirmed the results of the multivariate analyses. In patients who achieved CMR within 3 months, allo-SCT in CR1 had superior survival and lower relapse compared with the non-SCT cohort.

Effectiveness and safety of primary prophylaxis with G-CSF after induction therapy for acute myeloid leukemia: a systematic review and meta-analysis of the clinical practice guidelines for the use of G-CSF 2022 from the Japan society of clinical oncology

Although granulocyte colony-stimulating factor (G-CSF) reduces the incidence, duration, and severity of neutropenia, its prophylactic use for acute myeloid leukemia (AML) remains controversial due to a theoretically increased risk of relapse. The present study investigated the effects of G-CSF as primary prophylaxis for AML with remission induction therapy. A detailed literature search for related studies was performed using PubMed, Ichushi-Web, and the Cochrane Library. Data were independently extracted and assessed by two reviewers. A qualitative analysis of pooled data was conducted, and the risk ratio with corresponding confidence intervals was calculated in the meta-analysis and summarized. Sixteen studies were included in the qualitative analysis, nine of which were examined in the meta-analysis. Although G-CSF significantly shortened the duration of neutropenia, primary prophylaxis with G-CSF did not correlate with infection-related mortality. Moreover, primary prophylaxis with G-CSF did not affect disease progression/recurrence, overall survival, or adverse events, such as musculoskeletal pain. However, evidence to support or discourage the use of G-CSF as primary prophylaxis for adult AML patients with induction therapy remains limited. Therefore, the use of G-CSF as primary prophylaxis can be considered for adult AML patients with remission induction therapy who are at a high risk of infectious complications.

Recurrent Stroke with Rapid Development of Intracranial Artery Stenosis and Subsequent Successful Mechanical Thrombectomy in Essential Thrombocythemia

Essential thrombocythemia is a myeloproliferative neoplasm. Ischemic stroke is frequently the first manifestation of essential thrombocythemia. We herein report a patient with JAK2V617 mutation-positive essential thrombocythemia who developed recurrent ischemic stroke with rapid development of intracranial artery stenosis and subsequently underwent successful mechanical thrombectomy. The high JAK2V617F allele burden in our patient (58.4%) may have affected the patient's condition. We discuss similar reports in the literature and the possible pathophysiologic mechanism of large artery involvement in these patients.

Sperm replacement in sperm-storage tubules causes last-male sperm precedence in chickens

1. This study elucidated the last-male sperm precedence (LMSP) mechanism in chickens by examining replacement in storage tubules (SSTs) after multiple artificial inseminations (AI) and the effects of seminal plasma (SP) and male breed on sperm replacement in SSTs.2. Hens were artificially inseminated with fluorescent dye-labelled spermatozoa from White Leghorn (WL) chickens. Secondary AI was conducted 3 d later with sperm labelled with different nuclear fluorescent dye. Percentage of first and second inseminated sperm in SSTs and their logarithmic odds were calculated. The effect of SP on LMSP was examined using (1) Lake's solution-washed sperm before second insemination, and (2) SP injected continuously after first insemination. Effect of breed difference on sperm replacement was investigated using Barred Plymouth Rock (BP) sperm.3. Successive WL-sperm inseminations at three-day intervals caused > 70% stored sperm replacement in SSTs. Although SP removal from sperm from second insemination significantly decreased replacement, its intra-vaginal injection did not affect release. Secondary insemination using BP sperm significantly increased replacement.4. Sperm replacement is a major factor favouring LMSP in domestic chickens. Two fluorescent staining of sperm, and intra-vaginal multiple AI technique have enabled visualisation, differentiation, and quantification of multiple inseminated sperm stored in the SSTs.

Clinical impact and characteristics of erythroid dysplasia in adult aplastic anaemia: Results from a multicentre registry

Morphological dysplasia in haematopoietic cells, defined by a 10% threshold in each lineage, is one of the diagnostic criteria for myelodysplastic neoplasms. Dysplasia limited to the erythroid lineage has also been reported in some cases of aplastic anaemia (AA); however, its significance remains unclear. We herein examined the impact of erythroid dysplasia on immunosuppressive therapy responses and survival in AA patients. The present study included 100 eligible AA patients without ring sideroblasts. Among them, 32 had dysplasia in the erythroid lineage (AA with minimal dysplasia [mini-D]). No significant sex or age differences were observed between AA groups with and without erythroid dysplasia. In severe/very severe AA and non-severe AA patients, a response to anti-thymocyte globulin + ciclosporin within 12 months was observed in 80.0% and 60.0% of AA with mini-D and 42.9% and 90.0% of those without dysplasia, with no significant difference (p = 0.29 and p = 0.24 respectively). Overall survival and leukaemia-free survival did not significantly differ between the groups. Collectively, the present results indicate that the presence of erythroid dysplasia did not significantly affect clinical characteristics or outcomes in AA patients, suggesting that its presence in AA is acceptable. Therefore, erythroid dysplasia should not exclude an AA diagnosis.

Laboratory Evolution of Antimicrobial Resistance in Bacteria to Develop Rational Treatment Strategies

Laboratory evolution studies, particularly with Escherichia coli, have yielded invaluable insights into the mechanisms of antimicrobial resistance (AMR). Recent investigations have illuminated that, with repetitive antibiotic exposures, bacterial populations will adapt and eventually become tolerant and resistant to the drugs. Through intensive analyses, these inquiries have unveiled instances of convergent evolution across diverse antibiotics, the pleiotropic effects of resistance mutations, and the role played by loss-of-function mutations in the evolutionary landscape. Moreover, a quantitative analysis of multidrug combinations has shed light on collateral sensitivity, revealing specific drug combinations capable of suppressing the acquisition of resistance. This review article introduces the methodologies employed in the laboratory evolution of AMR in bacteria and presents recent discoveries concerning AMR mechanisms derived from laboratory evolution. Additionally, the review outlines the application of laboratory evolution in endeavors to formulate rational treatment strategies.

Outcomes of transplant-eligible patients with myelodysplastic syndrome with excess blasts registered in an observational study: The JALSG-CS11-MDS-SCT

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is the sole curative therapy for myelodysplastic syndrome (MDS). However, whether bridging therapy (BRT) including azacitidine (AZA) and combination chemotherapy (CCT) prior to allo-SCT should be performed is unclear. We analyzed BRT and the outcomes of patients with myelodysplastic syndrome with excess blasts (MDS-EB) who were ≤ 70 years old at the time of registration for a prospective observational study to clarify the optimal allo-SCT strategy for high-risk MDS. A total of 371 patients were included in this study. Among 188 patients (50.7%) who were considered for allo-SCT, 141 underwent allo-SCT. Among the patients who underwent allo-SCT, 64 received AZA, 29 received CCT, and 26 underwent allo-SCT without BRT as the initial treatment. Multivariate analysis identified BRT as an independent factor influencing overall survival (AZA vs. without BRT, hazard ratio [HR] 3.33, P = 0.005; CCT vs. without BRT, HR 3.82, P = 0.003). In multivariate analysis, BRT was independently associated with progression-free survival (AZA vs. without BRT: HR, 2.23; P = 0.041; CCT vs. without BRT: HR, 2.94; P = 0.010). Transplant-eligible patients with MDS-EB should undergo allo-SCT when clinically acceptable, and upfront allo-SCT without BRT may be superior to AZA or CCT.

Whole-genome sequencing analysis of molecular epidemiology and silent transmissions causing meticillin-resistant Staphylococcus aureus bloodstream infections in a university hospital

BACKGROUND

The emergence of novel genomic-type clones, such as community-associated meticillin-resistant Staphylococcus aureus (MRSA) and livestock-associated MRSA, and their invasion into hospitals have become major concerns worldwide; however, little information is available regarding the prevalence of MRSA in Japan. Whole-genome sequencing (WGS) has been conducted to analyse various pathogens worldwide. Therefore, it is important to establish a genome database of clinical MRSA isolates available in Japan.

AIM

A molecular epidemiological analysis of MRSA strains isolated from bloodstream-infected patients in a Japanese university hospital was conducted using WGS and single-nucleotide polymorphism (SNP) analysis. Additionally, through a review of patients' clinical characteristics, the effectiveness of SNP analysis as a tool for detecting silent nosocomial transmission that may be missed by other methods was evaluated in diverse settings and various time points of detection.

METHODS

Polymerase-chain-reaction-based staphylococcal cassette chromosome mec (SCCmec) typing was performed using 135 isolates obtained between 2014 and 2018, and WGS was performed using 88 isolates obtained between 2015 and 2017.

FINDINGS

SCCmec type II strains, prevalent in 2014, became rare in 2018, whereas the prevalence of SCCmec type IV strains increased from 18.75% to 83.87% of the population, and became the dominant clones. Clonal complex (CC) 5 CC8 and CC1 were detected between 2015 and 2017, with CC1 being dominant. In 88 cases, SNP analyses revealed nosocomial transmissions among 20 patients which involved highly homologous strains.

CONCLUSIONS

Routine monitoring of MRSA by whole-genome analysis is effective not only for gaining knowledge regarding molecular epidemiology, but also for detecting silent nosocomial transmission.

Granular flow experiment using artificial gravity generator at International Space Station

Studying the gravity-dependent characteristics of regolith, fine-grained granular media covering extra-terrestrial bodies is essential for the reliable design and analysis of landers and rovers for space exploration. In this study, we propose an experimental approach to examine a granular flow under stable artificial gravity conditions for a long duration generated by a centrifuge at the International Space Station. We also perform a discrete element simulation of the granular flow in both artificial and natural gravity environments. The simulation results verify that the granular flows in artificial and natural gravity are consistent. Further, regression analysis of the experimental results reveals that the mass flow rate of granular flow quantitatively follows a well-known physics-based law with some deviations under low-gravity conditions, implying that the bulk density of the granular media decreases with gravity. This insight also indicates that the bulk density considered in simulation studies of space probes under low-gravity conditions needs to be tuned for their reliable design and analysis.

Association between habitual hot spring bathing and depression in Japanese older adults: A retrospective study in Beppu

OBJECTIVES

Thermal therapy is used to manage various psychological diseases, such as depression. We investigated the relationship between hot spring bathing and depression in older adults using questionnaire responses.

DESIGN AND SETTING

We comprehensively evaluated the preventive effects of long-term hot spring bathing in 10429 adults aged ≥ 65 years in Beppu, Japan, by conducting a questionnaire study on the prevalence of depression (n = 219).

MAIN OUTCOME MEASURES

Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a multivariable logistic regression model for history of depression.

RESULTS

A separate multivariable logistic regression model for inference showed that female sex (OR, 1.56; 95 % CI, 1.17-2.08; p = 0.002), arrhythmia (OR, 1.73; 95 % CI, 1.18-2.52; p = 0.004), hyperlipidemia (OR, 1.63; 95 % CI, 1.14-2.32; p = 0.006), renal disease (OR, 2.26; 95 % CI, 1.36-3.75; p = 0.001), collagen disease (OR, 2.72; 95 % CI, 1.48-5.02; p = 0.001), allergy (OR, 1.97; 95 % CI, 1.27-3.04; p = 0.002), and habitual daily hot spring bathing (OR, 0.63; 95 % CI, 0.41-0.94; p = 0.027) were independently significantly associated with a history of depression.

CONCLUSIONS

We found an inverse relationship between habitual daily hot spring bathing and history of depression. Prospective randomized controlled trials on habitual daily hot spring bathing as a treatment for depression are warranted to investigate whether the use of hot springs can provide relief to those with psychiatric and mental health disorders.

[Thoracic SMARCA4-deficient undifferentiated tumor resembling malignant lymphoma]

We present a case of thoracic SMARCA4-deficient undifferentiated tumor that needed to be differentiated from malignant lymphoma owing to multiple lymph node swelling and marrow involvement. A 52-year-old man developed multiple lymphadenopathies along with anorexia, general fatigue, fever, and sweating 2 months prior to admission. ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) scan revealed a mass lesion on the right upper lung, generalized lymph node swelling, and bone metastasis, indicating the presence of suspicious lung cancer; therefore, he was referred to our hospital. Malignant lymphoma was suspected at the time of admission because of elevated levels of lactate dehydrogenase (11,977 U/l) and soluble interleukin 2 receptor (2,152 U/ml) as well as marrow infiltration of large abnormal cells. On day 11, the patient died from rapid respiratory failure. Histological and immunohistochemical features of the pleural effusion cell block led to the diagnosis of thoracic SMARCA4-deficient undifferentiated tumor. Thoracic SMARCA4-deficient undifferentiated tumor was recently introduced in the 2021 World Health Organization classification of lung tumors, with most patients being young adults with a history of heavy smoking and poor prognosis. Because of the multiple lymph node swelling and marrow involvement, this undifferentiated tumor should be distinguished from malignant lymphoma.

Analysis of the evolution of resistance to multiple antibiotics enables prediction of the Escherichia coli phenotype-based fitness landscape

The fitness landscape represents the complex relationship between genotype or phenotype and fitness under a given environment, the structure of which allows the explanation and prediction of evolutionary trajectories. Although previous studies have constructed fitness landscapes by comprehensively studying the mutations in specific genes, the high dimensionality of genotypic changes prevents us from developing a fitness landscape capable of predicting evolution for the whole cell. Herein, we address this problem by inferring the phenotype-based fitness landscape for antibiotic resistance evolution by quantifying the multidimensional phenotypic changes, i.e., time-series data of resistance for eight different drugs. We show that different peaks of the landscape correspond to different drug resistance mechanisms, thus supporting the validity of the inferred phenotype-fitness landscape. We further discuss how inferred phenotype-fitness landscapes could contribute to the prediction and control of evolution. This approach bridges the gap between phenotypic/genotypic changes and fitness while contributing to a better understanding of drug resistance evolution.

A manually curated compendium of expression profiles for the microbial cell factory Corynebacterium glutamicum

Corynebacterium glutamicum is the major host for the industrial production of amino acids and has become one of the best studied model organisms in microbial biotechnology. Rational strain construction has led to an improvement of producer strains and to a variety of novel producer strains with a broad substrate and product spectrum. A key factor for the success of these approaches is detailed knowledge of transcriptional regulation in C. glutamicum. Here, we present a large compendium of 927 manually curated microarray-based transcriptional profiles for wild-type and engineered strains detecting genome-wide expression changes of the 3,047 annotated genes in response to various environmental conditions or in response to genetic modifications. The replicates within the 927 experiments were combined to 304 microarray sets ordered into six categories that were used for differential gene expression analysis. Hierarchical clustering confirmed that no outliers were present in the sets. The compendium provides a valuable resource for future fundamental and applied research with C. glutamicum and contributes to a systemic understanding of this microbial cell factory.

Measurement(s)	Gene Expression Analysis
Technology Type(s)	Two Color Microarray
Factor Type(s)	WT condition A vs. WT condition B • Plasmid-based gene overexpression in parental strain vs. parental strain with empty vector control • Deletion mutant vs. parental strain
Sample Characteristic - Organism	Corynebacterium glutamicum
Sample Characteristic - Environment	laboratory environment
Sample Characteristic - Location	Germany

P-039 Male age is associated with sperm DNA integrity: Selection of high DNA integrity sperm by microfluidics sorting is critical to clinical outcomes in older patients

Study question

Does sperm DNA integrity affect clinical outcomes of ICSI?

Summary answer

Use of high DNA integrity sperm selected by microfluidics sperm sorting results in lower miscarriage rates in the patients of 39-years old and more.

What is known already

High sperm DNA damage is associated with decreased normal fertilization, embryo development and pregnancy rates, and an increased miscarriage rate. On the other hand, oocytes from older women have decreased pregnancy rate, and increased miscarriage rate because of possibility of low ability to repair sperm with DNA fragmentation, and dramatical increases of aneuploidy as women age. A microfluidic sperm selection chamber (MSS, ZyMōt™; DxNow) is a device designed to collect sperm with higher chromatin integrity than density gradient centrifugation (DGC).

Study design, size, duration

Sperm analysis was performed by sperm chromatin dispersion (SCD) test and comet assay in the same sample of 15 cases between October 2020 and February 2021. ICSI outcomes by DGC and MSS were compared with blastocyst development, and pregnancy rates in vitrified-thawed single blastocyst transfers cycle for 518 cases between August 2018 and May 2021.

Participants/materials, setting, methods

SCD test was optimized as a rapid procedure, with sperm showing a halo deemed normal, and those without a halo abnormal. Comet assay results were analyzed using CometScore 2.0, with comparison of %Tail DNA. ICSI outcomes were analyzed using multiple logistics regressions of male and female ages.

Main results and the role of chance

We found a positive correlation between male age and sperm DNA fragmentation rates in raw semen using SCD test (r = 0.70) and Comet assay (r = 0.42). Higher DNA integrity sperm could select using MSS than DGC. In this study with ICSI outcomes, 170 of 318 (53.5%) blastocyst transfers resulted in pregnancy, and 49 (28.8%) subsequently miscarried. The data were classified according to less than or more than 39 years old of male age detected by multiple logistics regressions. In patients with ≥39 years of male age, the female age was significantly higher and blastocyst and pregnancy rates were significantly lower, and the miscarriage rate was significantly higher than &lt;39 years of male age. Since sperm DNA fragmentation increased in accordance with male age, we compared MSS and DGC in the patients with male age ≥39 years. There was no significant difference in blastocyst, pregnancy, and miscarriage rates in female age &lt;39 years. While in ≥ 39 years of female age, blastocyst and pregnancy rates in MSS were not significantly different from DGC, but the miscarriage rate in MSS was significantly lower than in DGC (27.3 vs. 57.1%).

Limitations, reasons for caution

The sample size for each study was small. Analysis of sperm DNA fragmentation and samples in ICSI outcomes were not the same. The retrospective nature of ICSI outcomes in this study does not allow controlling of unknown confounders.

Wider implications of the findings

Sperm DNA fragmentation depended on male age affected fertility outcomes. However, when male age is higher, masking the effect of male age by female age. In this study, we found out the improvement of ICSI outcome by using high DNA integrity sperm selected by MSS in both ≥39 years.

Trial registration number

Not applicable

POS1441 INFLUENCE OF ENVIRONMENTAL AND GENETIC FACTORS ON SERUM IGG4 DURING HEALTH CHECKUPS IN NAGASAKI ISLAND STUDY

Background

Although serum IgG4 levels are important for the diagnosis of IgG4-related diseases (IgG4-RD), few studies have validated IgG4 levels in healthy individuals in large resident medical examination cohorts and investigated background factors associated with serum IgG4.

A report on genetic factors shows that HLA loci associate with IgG4-RD found in Japanese nation-wide IgG4-RD registry1). However, environmental and genetic factors related to the elevated serum IgG4 levels, which may closely associate with development of IgG4-RD, have previously been unclear in healthy subjects. The nephelometric immunoassay (NIA) is conventionally used to measure IgG4, but it requires a relatively large amount of serum. The magnetic bead panel assay (MBA), which can evaluate IgG4 levels with only a few ml of serum, has an advantage compared with NIA regarding to required sample volume, but the correlation between the two methods is unclear.

Objectives

First, we attempted to verify the accuracy of the MBA compared to the standard NIA in the first cohort. Next, we examined the relationship between IgG4 measured by the MBA and background information of healthy subjects to identify variables that correlate with serum IgG4 in the second cohort.

Methods

First, Kanazawa University collected 947 samples from the resident health examination, and IgG4 levels were measured by both MBA and NIA, and the correlation between the two was verified using Spearman’s rank correlation coefficient (first cohort). Next (second cohort), serum IgG4 of 3240 samples of Nagasaki Island Study (NaIS), which had started in 2014 collaborating among Nagasaki University and Goto City, Nagasaki Prefecture, intended for research of varying conditions and diseases including IgG4-RD, were then measured by MBA. These subjects were stratified into the two groups as IgG4-high and IgG4-within normal limit using the aforementioned cutoff values, and compared with background information such as age, gender, drinking, smoking, uric acid, serum creatinine, comorbidities and HLA typing, including DRB1*04:06, *04:03, *04:05, *04:10 as disease-susceptibility gene, DRB1*09:01 and DQB1*03:03 as protective gene1).

Results

IgG4 by MBA correlated well with IgG4 by NIA (r=0.94, p-value<0.001) which was determined from Kanazawa samples (N=947). 1,463.6 mg/mL of IgG4 of MBA corresponded to 135 mg/dl, the normal cut-off value for IgG4 by NIA. In the analysis of NaIS samples (N=3240), the overall high IgG4 positivity rate was 6.3%. Multivariable analysis including age, gender, smoking and drinking, led by univariate analysis, showed that gender and smoking were significantly associated with high serum IgG4 positivity (male: odds ratio = 1.8, 95%CI =1.2-2.7, p = 0.009, smoking: odds ratio = 1.7, 95%CI =1.1-2.5, p = 0.012). There was no association between high serum IgG4 level and HLA genotyping.

Conclusion

We concluded that MBA is a good method to measure serum IgG4 even by the very small sample volume. In our study, the prevalence of serum IgG4 positivity was high tendency than previous report2). Our data showed that male and smoking are independent factors associated with high serum IgG4 positivity. There were no association between serum IgG4 level and HLA genotyping in healthy subjects. Further comprehensive investigation is necessary to clarify high risk subjects who will develop IgG4-RD.

References

[1]Terao C, et al. Lancet Rheumatol 2019;1: e14–22.

[2]Carballo I, et al. PLoS One. 2016;11: e0149330.

Disclosure of Interests

None declared

AB0071 ANTI-ACETYLATED PROTEIN IgM-ANTIBODIES AS THE STARTING POINT OF AUTOANTIBODY FORMATION IN RHEUMATOID ARTHRITIS?

Background

Anti-modified protein antibodies (AMPA) are an important hallmark of rheumatoid arthritis (RA) and the fact that they have consistently been found to develop years before disease onset, has provided important insights into the immunopathology underlying RA. In (auto)antibody development, IgM is the first isotype to be produced. However, it is unclear whether IgM-autoimmunity differs between AMPA targeting different post-translational modifications (citrulline, homocitrulline and acetylated residues), which could provide clues about the starting point of the AMPA response.

Objectives

We therefore investigated IgM-levels of anti-citrullinated protein antibodies (ACPA), anti-carbamylated protein antibodies (anti-CarP) and anti-acetylated protein antibodies (AAPA) in healthy individuals, non-RA and RA patients.

Methods

Autoantibodies were investigated in 2 cohorts:

1) a Japanese cohort of healthy individuals (community based Nagasaki Island study) known to be ACPA-positive (n=65) or ACPA-negative (n=197) were compared to Dutch healthy donors (n=30) and ACPA-positive RA patients (n=29). ACPA, anti-CarP and AAPA IgG were measured by ELISAs using CCP4, CHcitP4 and CAcetylP4 peptides with sequences similar to the commercial CCP2 antigen and native control peptides.

2) early arthritis patients from the Leiden Early Arthritis Clinic who had RA (n=648) or another form of arthritis (non-RA, n=555) and healthy controls (n=80). ACPA and AAPA were determined by ELISAs using CCP2 and cACP2 peptides and their native control peptides, while anti-CarP was measured on homocitrullinated versus native fetal calf serum. Mann-Whitney U-tests were performed for statistical comparisons.

Results

ACPA IgM reactivity was mainly present in established ACPA-positive RA patients (Figure 1A) and to a lesser extent in ACPA-positive healthy Japanese individuals, and non-RA arthritis patients (Figure 1D). A similar picture was observed for anti-CarP IgM reactivity, for which again highest levels were found in established RA patients (1B and 1E) and ACPA-positive compared to ACPA-negative healthy Japanese individuals (1B). Intriguingly, AAPA IgM reactivity-levels displayed a different pattern as these were comparable between healthy individuals and ACPA-positive RA patients (1C and 1F). Likewise, AAPA IgM reactivity-levels were also not increased in ACPA-positive healthy Japanese individuals, who instead had lower levels compared to their ACPA-negative counterparts. Furthermore, the AAPA IgM-reactivity levels did not differ between non-RA arthritis patients, healthy controls and RA patients (1F). AAPA IgG-levels on the other hand were clearly elevated in RA patients compared to healthy controls and non-RA arthritis patients (1G).

Conclusion

AAPA are exceptional compared to other AMPA because IgM AAPA-levels are similar among healthy individuals, non-RA arthritis and RA patients. This suggests that AAPA IgM is part of the “normal” immune repertoire and could constitute the starting point for RA-associated AMPA responses, with isotype switching and epitope spreading to other post-translational modifications leading to the typical RA-associated mature AMPA response.

Disclosure of Interests

None declared

Bio-Interface on Freestanding Nanosheet of Microelectromechanical System Optical Interferometric Immunosensor for Label-Free Attomolar Prostate Cancer Marker Detection

Various biosensors that are based on microfabrication technology have been developed as point-of-care testing devices for disease screening. The Fabry–Pérot interferometric (FPI) surface-stress sensor was developed to improve detection sensitivity by performing label-free biomarker detection as a nanomechanical deflection of a freestanding membrane to adsorb the molecules. However, chemically functionalizing the freestanding nanosheet with excellent stress sensitivity for selective molecular detection may cause the surface chemical reaction to deteriorate the nanosheet quality. In this study, we developed a minimally invasive chemical functionalization technique to create a biosolid interface on the freestanding nanosheet of a microelectromechanical system optical interferometric surface-stress immunosensor. For receptor immobilization, glutaraldehyde cross-linking on the surface of the amino-functionalized parylene membrane reduced the shape variation of the freestanding nanosheet to 1/5–1/10 of the previous study and achieved a yield of 95%. In addition, the FPI surface-stress sensor demonstrated molecular selectivity and concentration dependence for prostate-specific antigen with a dynamic range of concentrations from 100 ag/mL to 1 µg/mL. In addition, the minimum limit of detection of the proposed sensor was 2,000,000 times lower than that of the conventional nanomechanical cantilevers.

Bendamustine-induced rash is associated with a favorable prognosis in patients with indolent B-cell lymphoma

Bendamustine is now recognized as a key drug for indolent B-cell lymphoma (iBCL), mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL). Skin toxicity associated with bendamustine is one of the characteristic adverse effects. We retrospectively examined the relationship between bendamustine-associated drug rashes and disease prognosis of iBCL and MCL at our institution. Between January 2011 and August 2019, 65 patients (39 men and 26 women, median age 68, range 41-84 years) were treated with bendamustine alone (n=11, 120 mg/m² on days 1 and 2) or a combination of rituximab and bendamustine (n=54, 90 mg/m² on days 1 and 2). Of these patients, 47 had follicular lymphoma (FL), 10 had MCL and 8 had other iBCLs. Drug rash occurred in 27 (41.5%). Eight cases (29.6%) were grade 1, 5 (18.5%) were grade 2 and 14 (51.9%) were grade 3. The onset was in the first course in 17 (63.0%), 2nd course in 5 (18.5%), 3rd course in 2 (7.4%), 4th course in 1 (3.7%) and 5th course in 2 (7.4%). No treatment was administered in 1 case (3.7%), topical steroid was applied in 10 (37.0%), antiallergic drug was administered in 2 (7.4%), topical steroid and antiallergic drug were administered in 5 (18.5%), and oral and topical steroid and antiallergic drug were administered in 9 (33.3%). The 3-year progression-free survival (PFS) and overall survival (OS) in patients with rash development were 80.0% and 85.5%, respectively, and those in patients without development were 36.4% and 54.0%, respectively (p=0.009 and 0.02, respectively). By multivariate analysis, the development of rash was associated with a better PFS and a diagnosis of iBCL was associated with a better OS. This study revealed that bendamustine-induced rash is associated with a favorable prognosis among patients with iBCL.

Acceleration of target production in co-culture by enhancing intermediate consumption through adaptive laboratory evolution

Co-culture is a promising way to alleviate metabolic burden by dividing the metabolic pathways into several modules and sharing the conversion processes with multiple strains. Since an intermediate is passed from the donor to the recipient via the extracellular environment, it is inevitably diluted. Therefore, enhancing the intermediate consumption rate is important for increasing target productivity. In the present study, we demonstrated the enhancement of mevalonate consumption in Escherichia coli by adaptive laboratory evolution and applied the evolved strain to isoprenol production in an E. coli (upstream: glucose to mevalonate)-E. coli (downstream: mevalonate to isoprenol) co-culture. An engineered mevalonate auxotroph strain was repeatedly sub-cultured in a synthetic medium supplemented with mevalonate, where the mevalonate concentration was decreased stepwise from 100 to 20 µM. In five parallel evolution experiments, all growth rates gradually increased, resulting in five evolved strains. Whole-genome re-sequencing and reverse engineering identified three mutations involved in enhancing mevalonate consumption. After introducing nudF gene for producing isoprenol, the isoprenol-producing parental and evolved strains were respectively co-cultured with a mevalonate-producing strain. At an inoculation ratio of 1:3 (upstream:downstream), isoprenol production using the evolved strain was 3.3 times higher than that using the parental strain.

Evolution of anti-modified protein antibody responses can be driven by consecutive exposure to different post-translational modifications

Background

Besides anti-citrullinated protein antibodies (ACPA), rheumatoid arthritis patients (RA) often display autoantibody reactivities against other post-translationally modified (PTM) proteins, more specifically carbamylated and acetylated proteins. Immunizing mice with one particular PTM results in an anti-modified protein antibody (AMPA) response recognizing different PTM-antigens. Furthermore, human AMPA, isolated based on their reactivity to one PTM, cross-react with other PTMs. However, it is unclear whether the AMPA-reactivity profile is “fixed” in time or whether consecutive exposure to different PTMs can shape the evolving AMPA response towards a particular PTM.

Methods

Longitudinally collected serum samples of 8 human individuals at risk of RA and 5 with early RA were tested with ELISA, and titers were analyzed to investigate the evolution of the AMPA responses over time. Mice (13 per immunization group in total) were immunized with acetylated (or carbamylated) protein (ovalbumin) twice or cross-immunized with an acetylated and then a carbamylated protein (or vice versa) and their serum was analyzed for AMPA responses.

Results

Human data illustrated dynamic changes in AMPA-reactivity profiles in both individuals at risk of RA and in early RA patients. Mice immunized with either solely acetylated or carbamylated ovalbumin (AcOVA or CaOVA) developed reactivity against both acetylated and carbamylated antigens. Irrespective of the PTM-antigen used for the first immunization, a booster immunization with an antigen bearing the other PTM resulted in increased titers to the second/booster PTM. Furthermore, cross-immunization skewed the overall AMPA-response profile towards a relatively higher reactivity against the “booster” PTM.

Conclusions

The relationship between different reactivities within the AMPA response is dynamic. The initial exposure to a PTM-antigen induces cross-reactive responses that can be boosted by an antigen bearing this or other PTMs, indicating the formation of cross-reactive immunological memory. Upon subsequent exposure to an antigen bearing another type of PTM, the overall reactivity pattern can be skewed towards better recognition of the later encountered PTM. These data might explain temporal differences in the AMPA-response profile and point to the possibility that the PTM responsible for the initiation of the AMPA response may differ from the PTM predominantly recognized later in time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02687-5.

Early tumor response assessment may avoid serious immune-related adverse events in nivolumab and ipilimumab combination therapy for stage IV melanoma

Nivolumab and ipilimumab combination therapy is one of the most promising treatments for patients with melanoma. However, this combination therapy is highly toxic and causes serious adverse events (SAEs) in more than half of the patients.

[Treatment for myelodysplastic syndromes and future perspectives in the genomic era]

Myelodysplastic syndrome (MDS) is a group of clonal diseases caused by the accumulation of genetic mutations. The outcome of MDS extremely varies, with an overall survival ranging from just a few months to years. Therefore, accurate classification and prognostic scoring are essential. Patients with MDS are generally divided into two risk groups. For low-risk patients, the treatment goal is to improve ineffective hematopoiesis and quality of life. Meanwhile, in high-risk patients, treatment aims to extend survival and prevent progression to leukemia. To date, different guidelines recommend azacytidine, which is a hypomethylating agent, as the initial treatment. This is the only therapy associated with a significant survival in high-risk patients who are not eligible for hematopoietic stem cell transplantation. However, the response rate is only about 40%, and responses are mostly transient. Recent advancements in sequencing technologies have improved our understanding of the molecular pathogenesis of MDS by identifying somatic mutations in almost each patient with MDS. The high phenotypic and clinical heterogeneity of patients with MDS is primarily based on genetics. Due to a high degree of heterogeneity, the treatment policy for patients with MDS is still challenging. In this review, we will discuss the current treatment strategies for MDS in Japan, including future perspectives.

Laboratory evolution of Mycobacterium on agar plates for analysis of resistance acquisition and drug sensitivity profiles

Drug-resistant tuberculosis (TB) is a growing public health problem. There is an urgent need for information regarding cross-resistance and collateral sensitivity relationships among drugs and the genetic determinants of anti-TB drug resistance for developing strategies to suppress the emergence of drug-resistant pathogens. To identify mutations that confer resistance to anti-TB drugs in Mycobacterium species, we performed the laboratory evolution of nonpathogenic Mycobacterium smegmatis, which is closely related to Mycobacterium tuberculosis, against ten anti-TB drugs. Next, we performed whole-genome sequencing and quantified the resistance profiles of each drug-resistant strain against 24 drugs. We identified the genes with novel meropenem (MP) and linezolid (LZD) resistance-conferring mutation, which also have orthologs, in M. tuberculosis H37Rv. Among the 240 possible drug combinations, we identified 24 pairs that confer cross-resistance and 18 pairs that confer collateral sensitivity. The acquisition of bedaquiline or linezolid resistance resulted in collateral sensitivity to several drugs, while the acquisition of MP resistance led to multidrug resistance. The MP-evolved strains showed cross-resistance to rifampicin and clarithromycin owing to the acquisition of a mutation in the intergenic region of the Rv2864c ortholog, which encodes a penicillin-binding protein, at an early stage. These results provide a new insight to tackle drug-resistant TB.

Mutational property of newly identified mutagen l-glutamic acid γ-hydrazide in Escherichia coli

We previously found that an l-glutamine analog l-glutamic acid γ-hydrazide has high mutagenic activity through the high-throughput laboratory evolution of Escherichia coli. In this study, mutagenicity and mutational property of l-glutamic acid γ-hydrazide were examined by the Ames test and mutation accumulation experiments using E. coli. The Ames test revealed that l-glutamic acid γ-hydrazide showed higher mutagenic activity without metabolic activation than known mutagens 2-aminoanthracene, and cobalt(II) acetate tetrahydrate. This result indicates that l-glutamic acid γ-hydrazide does not require metabolic activation for mutagenic activity in E. coli. Mutation accumulation experiments and whole-genome sequencing analysis revealed the number and spectrum of the accumulated mutations with or without l-glutamic acid γ-hydrazide. In the presence of l-glutamic acid γ-hydrazide, MDS42 strain accumulated 392.3 ± 116.2 point mutations during 30 passages corresponding to 777 generations, while MDS42 strain accumulated 1.5 ± 2.5 point mutations without l-glutamic acid γ-hydrazide during 50 passages corresponding to 1341 generations. The mutational spectrum of l-glutamic acid γ-hydrazide was G/C to A/T transition (82.2 ± 4.3 %) and A/T to G/C transition (17.4 ± 4.3 %). These results indicated that l-glutamic acid γ-hydrazide has a strong mutagenic activity.

Morphological change of coiled bacterium Spirosoma linguale with acquisition of β-lactam resistance

Spirosoma linguale is a gram-negative, coiled bacterium belonging to the family Cytophagaceae. Its coiled morphology is unique in contrast to closely related bacteria belonging to the genus Spirosoma, which have a short, rod-shaped morphology. The mechanisms that generate unique cell morphology are still enigmatic. In this study, using the Spirosoma linguale ATCC33905 strain, we isolated β-lactam (cefoperazone and amoxicillin)-resistant clones. These clones showed two different cell morphological changes: relatively loosely curved cells or small, horseshoe-shaped cells. Whole-genome resequencing analysis revealed the genetic determinants of β-lactam resistance and changes in cell morphology. The loose-curved clones commonly had mutations in Slin_5958 genes encoding glutamyl-tRNA amidotransferase B subunit, whereas the small, horseshoe-shaped clones commonly had mutations in either Slin_5165 or Slin_5509 encoding pyruvate dehydrogenase (PDH) components. Two clones, CFP1ESL11 and CFL5ESL4, which carried only one mutation in Slin_5958, showed almost perfectly straight, rod-shaped cells in the presence of amoxicillin. This result suggests that penicillin-binding proteins targeted by amoxicillin play an important role in the formation of a coiled morphology in this bacterium. In contrast, supplementation with acetate did not rescue the growth defect and abnormal cell size of the CFP5ESL9 strain, which carried only one mutation in Slin_5509. These results suggest that PDH is involved in cell-size maintenance in this bacterium.

POS1429 ORAL DYSBIOSIS REFLECTS THE IMMUNOLOGICAL ALTERATION OF RA REGARDING TO HLA DRB1*SE, ACPA AND CIGARETTE SMOKING: NAGASAKI ISLAND STUDY

Background:

Anti-citrullinated protein antibody (ACPA) production is observed in several organs even prior to the onset of rheumatoid arthritis (RA), and oral mucosa is considered to be one of the important tissues. Saliva is considered to reflect the oral microbiota(oralMB) including periodontal disease. A gene-environment interaction between cigarette smoking and shared epitope genes in HLA-DRB1*shared epitope (SE) provides a high risk of ACPA-positive RA. However, the interaction of HLA-DRB1*SE, ACPA, cigarette smoking and oralMB of RA patients remains to be elucidated.

Objectives:

We investigated that the difference of oralMB among RA patients and healthy subjects(HS) regarding to ACPA, HLA-DRB1*SE and cigarette smoking.

Methods:

The Nagasaki Island Study, which had started in 2014 collaborating with Goto City, Nagasaki Prefecture, Japan, is intended for research of the preclinical stage of RA, including ACPA, HLA genotype screening, oralMB and lifestyle habit. Both of blood and salivary samples were obtained from 1422 subjects out of 4276 participants in this study from 2016 to 2018. ACPA positivity was 1.7 % in total 4276 subjects. At this point, we selected 291 subjects, who were ACPA positive non-RA HS(n=22) and patients with RA (n=33, 11 subjects were ACPA positive and 22 ACPA negative, respectively) as the case, age and gender matched ACPA negative non-RA HS (n=236) as the control. In RA subjects, current smoker was n=1(3.0%) and ever smoker was n=8(24.2%). In HS, current smoker was n=29(11.2%) and ever smoker was n=55(21.3%). ACPA was measured by ELISA, and HLA genotyping was quantified by next-generation sequencing (Ref.1). The operational taxonomic unit (OTU) analysis using 16S rRNA gene sequencing were performed. The richness of microbial diversity within subject (α-diversity) was scaled via Shannon entropy. The dissimilarity between microbial community composition was calculated using Bray-Curtis distance as a scale, and differences between groups (β-diversity) were tested by permutational multivariate analysis of variance (PERMANOVA). In addition, UniFrac distance calculated in consideration of the distance on the phylogenetic tree were performed.

Results:

Median age 71 y.o., % Female 58.4 %. Among RA and non-RA subjects, not α-diversity but β-diversity was statistically smaller significantly in RA (p=0.022). In the HS, there was no decrease in α-diversity between the ACPA-positive and HLA-DRB1*SE-positive groups, but in the ACPA-positive group, there was a decrease in α-diversity in the HLA-DRB1*SE-positive group. When we compared α-diversity stratified by the presence or absence of three factors (RA, ACPA, and HLA-DRB1*SE), the RA group with ACPA and HLA-DRB1*SE positive tended to have the lowest diversity (Figure 1 lower right). RA subjects, presence of HLA-DRB1*SE did not show the difference but the tendency of lower α-diversity (p=0.29).

Conclusion:

HS with ACPA-positive HLA-DRB1*SE tended to show lower α-diversity than ACPA-positive HS and HLA-DRB1*SE positive HS. Furthermore, RA subjects with ACPA-positive HLA-DRB1*SE showed lower α-diversity than HS with ACPA-positive HLA-DRB1*SE.

Our study suggested that the oral dysbiosis may reflect the immunological status of patients with RA. Because of the small number of ACPA-positive patients, stratification by smoking history was difficult. Further examination is needed to clarify the gene-environment interaction and microbiome.

References:

[1]Kawaguchi S, et al. Methods Mol Biol 2018;1802: 22.

Disclosure of Interests:

None declared

POS0386 EVOLUTION OF ANTI-MODIFIED PROTEIN ANTIBODY RESPONSES CAN BE DRIVEN BY CONSECUTIVE EXPOSURE TO DIFFERENT POST-TRANSLATIONAL MODIFICATIONS

Background:

Besides anti-citrullinated protein antibodies (ACPA), rheumatoid arthritis patients (RA) often display autoantibody reactivities against other post-translationally modified (PTM) proteins, more specifically carbamylated and acetylated proteins. Immunizing mice with one PTM results in an anti-modified protein antibody (AMPA) response recognizing multiple PTMs. Furthermore, human AMPA, isolated based on their reactivity to one PTM, cross-react with other PTMs at the monoclonal and polyclonal level. However, it is unclear whether the AMPA reactivity profile is “fixed” in time, or whether consecutive exposure to different PTMs can shape the evolving AMPA-response.

Objectives:

To investigate the evolution of the AMPA response in mice with controlled exposure to PTMs as well as in AMPA-positive humans.

Methods:

Mice were immunized with acetylated (or carbamylated) protein (ovalbumin) twice or cross-immunized with an acetylated and then a carbamylated protein (or vice versa) and their serum was analyzed for AMPA responses with ELISA using a different backbone protein (fibrinogen) bearing the same modifications. Longitudinally collected serum samples of human individuals at risk of RA and with early RA were tested to investigate the evolution of the AMPA responses in humans.

Results:

Mice immunized twice with either solely acetylated or solely carbamylated ovalbumin (AcOVA or CaOVA) developed reactivity against both acetylated and carbamylated antigens. Irrespective of the PTM used for the first immunization, a booster immunization with the other PTM resulted in increased titers to the second/booster PTM (Figure 1A), suggesting that immunization with a defined PTM-antigen leads to the generation of anti-PTM memory B cells able to cross-recognize other PTMs. Furthermore, immunizing with CaOVA and boosting with AcOVA (or vice versa) skewed the overall AMPA-response profile towards a relatively higher reactivity against the “booster” PTM (Figure 1B). Human data also illustrated dynamic changes in AMPA reactivity profiles in both individuals at risk of RA and in early RA patients (not shown).

Conclusion:

The relationship between different reactivities within the AMPA response is dynamic. The initial exposure to a PTM antigen induces cross-reactive response that can be boosted by the same or other PTMs. The overall reactivity pattern can be skewed by subsequent exposure to other PTMs. These data might explain temporal changes in the reactivity profile of the AMPA response and point to the possibility that the PTM responsible for the initiation of the AMPA response may differ from the PTM predominantly recognized later in time.

Disclosure of Interests:

None declared

Subsequent shock delivery and outcomes in out-of-hospital cardiac arrests with initial unshockable rhythm

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research)

Background

The conversion from initial non-shockable to shockable rhythms during cardiopulmonary resuscitation (CPR) by emergency medical service (EMS) providers may be associated with neurologically intact survival after out-of-hospital cardiac arrest (OHCA). However, the prognostic significance of rhythm conversion according to the type of initial nonshockable rhythm is unclear.

Purpose

To determine the association between shock after conversion to shockable rhythm with neurologically intact survival after OHCA and shock delivery time (time from EMS-initiated CPR to first shock delivery) in patients with two types of initial unshockable rhythm.

Methods

We analyzed the records of 90,334 adult patients with witnessed OHCA of cardiac origin who were treated by EMS providers and had an initial unshockable rhythm. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database for a 5-year period (2013–2017). The primary outcome was 1-month neurologically intact survival, defined as a cerebral performance categories score from 1 to 2. Patients were divided into initial pulseless electrical activity (PEA) (n = 37,977 [42.0%]) and initial asystole (n = 52,357 [58.0%]) groups.

Results

In the initial PEA group, the crude rate of 1-month neurologically intact survival was significantly higher in the subsequently shocked than in the non-shocked patients (4.2% [121/2,896]) vs. 2.4% [857/35,081], p &lt;0.0001). After adjustment for ten prehospital variables, the adjusted odds ratios (aORs) of subsequent shock for 1-month neurologically intact survival compared to no shock delivery were as follows: shock delivery time &lt;10 min, 2.21 (95% confidence interval [CI], 1.77–2.77, p&lt; 0.0001); 10–14 min, 1.43 (0.89–2.28, p = 0.14); and ≥15 min, 0.36 (0.16–0.81; p = 0.013). In the initial asystole group, the crude rate of 1-month neurologically intact survival was significantly higher in the subsequently shocked than in the non-shocked (1.7% [47/2,687] vs. 0.4% [203/49,670], p &lt;0.0001). A multivariate logistic regression model showed that subsequent shock with a shock delivery time &lt;10 min was associated with increased odds of neurologically intact survival compared to no shock delivery (aOR, 5.67; 95% CI, 3.92–8.18; p &lt;0.0001). However, there were no significant differences in neurological outcomes between subsequently shocked and non-shocked patients when the shock delivery time was 10–14 min (p = 0.21) or ≥15 min (p = 0.91).

Conclusions

In patients with witnessed OHCA of cardiac origin and initial nonshockable rhythm, subsequent shock after conversion to shockable rhythm during CPR was associated with increased odds of 1-month neurologically intact survival only when shock was delivered &lt;10 min from EMS-initiated CPR, regardless of the type of initial rhythm. Further, in patients with initial PEA, subsequent shock was associated with decreased odds of neurologically intact survival when shock was delivered ≥15 min from EMS-initiated CPR.

Association of subsequent shock after conversion to shockable rhythm with outcomes stratified by the type of initial non-shockable rhythm in children with out-of-hospital cardiac arrest

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research)

Background/Introduction: The rhythm conversion from initial non-shockable to shockable rhythm during cardiopulmonary resuscitation (CPR) by emergency medical services (EMS) providers may be associated with neurologically intact survival after out-of-hospital cardiac arrest (OHCA) in children with an initial non-shockable rhythm. However, the prognostic significance of rhythm conversion stratified by the type of initial non-shockable rhythm is still unclear.

Purpose

We aimed to investigate the association of subsequent shock after rhythm conversion to shockable rhythm with neurologically intact survival and shock delivery time (time from EMS-initiated CPR to first shock delivery) by the type of initial non-shockable rhythm in children with OHCA.

Methods

We analysed the records of 19,095 children (age &lt;18 years) with OHCA treated by EMS providers. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database for a 13-year period (2005–2017). The primary outcome measure was 1-month neurologically intact survival, defined as cerebral performance category score of 1 to 2. Patients were divided into the initial pulseless electrical activity (PEA) (n = 3,326 [17.4%]) and initial asystole (n = 15,769 [82.6%]) groups.

Results

The proportion of patients who received subsequent shock after conversion to shockable rhythm was significantly higher in the initial PEA than in the initial asystole groups (3.3% [109/3,326] vs. 1.4% [227/15,769], p &lt; 0.0001). The shock delivery time was significantly shorter in the initial PEA than in the initial asystole groups (median [IQR], 8 min [5 min – 12 min] vs. 10 min [6 min – 16 min], p &lt; 0.01). Among the initial PEA patients, there was no significant difference between subsequently shocked (10.0% [11/109]) and subsequently non-shocked patients (6.0% [192/3,217], p = 0.10) regarding the rate of 1-month neurologically intact survival. However, after adjusting for 9 pre-hospital variables, subsequent shock with a delivery time of &lt;10 min was associated with increased odds of neurologically intact survival compared with no shock delivery (adjusted odds ratio [OR], 2.45; 95% confidence interval [CI], 1.16–5.16], p = 0.018). Among the initial asystole patients, the rate of 1-month neurologically intact survival was significantly higher in the subsequently shocked (4.4% [10/227]) than in the subsequently non-shocked (0.7% [106/15,542], p &lt; 0.0001). A multivariate logistic regression model showed that subsequent shock with a delivery time of &lt;10 min was associated with increased odds of neurologically intact survival compared with no shock delivery (adjusted OR, 9.77 [95% CI, 4.2–22.5], p &lt; 0.0001).

Conclusions

In children with OHCA with an initial non-shockable rhythm, subsequent shock after conversion to shockable rhythm during CPR was associated with increased odds of 1-month neurologically intact survival only when shock was delivered &lt;10 min from EMS-initiated CPR regardless of the type of initial rhythm.

Antibacterial properties of phenothiazine derivatives against multidrug-resistant Acinetobacter baumannii strains

AIM

As options to treat recalcitrant bacterial infections which are increasingly limited due to multidrug-resistant strains, searching for new, effective antibacterial compounds is necessary. One strategy is to generate treatment alternatives by drug repurposing.

METHODS AND RESULTS

In this work, phenotypic microarrays were used for the screening of miscellaneous compounds against the growth and biofilm formation of Acinetobacter baumannii, an important emergent multidrug-resistant opportunistic pathogen. The results showed that the phenothiazine derivatives, such as promethazine, trifluoperazine, thioridazine, and chlorpromazine, inhibited the growth of antibiotic-sensitive and multidrug-resistant strains (showing minimal inhibitory concentrations ranging from 0·05 to 0·6 g l^-1 and minimal bactericidal concentrations ranging from 0·1 to 2·5 g l^-1 ). All phenothiazine derivatives were active against biofilm cells (with minimal biofilm eradication concentrations ranging from 0·5 to >3 g l^-1 ). Chlorpromazine promoted reactive oxigen species (ROS) production, and cell membrane and DNA damage. Chlorpromazine showed synergy with antibiotics such as ceftazidime, meropenem, and colistin and was an effective treatment for experimentally infected Galleria mellonella when combined with ceftazidime.

CONCLUSIONS

It was demonstrated that phenothiazine derivatives, especially chlorpromazine, are drugs with attractive antibacterial properties against nosocomial MDR strains of A. baumannii, by generating ROS and cell membrane and DNA damage.

SIGNIFICANCE AND IMPACT OF THE STUDY

The present study indicates that repurposing phenothiazine derivatives for treating recalcitrant infections by A. baumannii could be promising.

Relevance of NADH Dehydrogenase and Alternative Two-Enzyme Systems for Growth of Corynebacterium glutamicum With Glucose, Lactate, and Acetate

The oxidation of NADH with the concomitant reduction of a quinone is a crucial step in the metabolism of respiring cells. In this study, we analyzed the relevance of three different NADH oxidation systems in the actinobacterial model organism Corynebacterium glutamicum by characterizing defined mutants lacking the non-proton-pumping NADH dehydrogenase Ndh (Δndh) and/or one of the alternative NADH-oxidizing enzymes, L-lactate dehydrogenase LdhA (ΔldhA) and malate dehydrogenase Mdh (Δmdh). Together with the menaquinone-dependent L-lactate dehydrogenase LldD and malate:quinone oxidoreductase Mqo, the LdhA-LldD and Mdh-Mqo couples can functionally replace Ndh activity. In glucose minimal medium the Δndh mutant, but not the ΔldhA and Δmdh strains, showed reduced growth and a lowered NAD+/NADH ratio, in line with Ndh being the major enzyme for NADH oxidation. Growth of the double mutants ΔndhΔmdh and ΔndhΔldhA, but not of strain ΔmdhΔldhA, in glucose medium was stronger impaired than that of the Δndh mutant, supporting an active role of the alternative Mdh-Mqo and LdhA-LldD systems in NADH oxidation and menaquinone reduction. In L-lactate minimal medium the Δndh mutant grew better than the wild type, probably due to a higher activity of the menaquinone-dependent L-lactate dehydrogenase LldD. The ΔndhΔmdh mutant failed to grow in L-lactate medium and acetate medium. Growth with L-lactate could be restored by additional deletion of sugR, suggesting that ldhA repression by the transcriptional regulator SugR prevented growth on L-lactate medium. Attempts to construct a ΔndhΔmdhΔldhA triple mutant were not successful, suggesting that Ndh, Mdh and LdhA cannot be replaced by other NADH-oxidizing enzymes in C. glutamicum.

Indolent T-cell lymphoproliferative disorder of the stomach successfully treated by radiotherapy

Successful treatment of indolent T-cell lymphoproliferative disorder of the gastrointestinal tract (ITLPDGI) by chemotherapy is rare and watchful waiting is often performed for asymptomatic patients. We report a case of ITLPDGI successfully treated by involved field radiotherapy (IFRT). The patient presented with slow ITLPDGI localised to the stomach with mild symptoms. IFRT (30 Gy/20f) was administered, after which endoscopy revealed resolution of lesions and blood vessel appearance, and absence of proliferating abnormal lymphocytes was confirmed by biopsy. The patient remains lymphoma-free 1 year post-treatment. Although long-term follow-up and additional cases are essential for the evaluation of IFRT as a treatment option for localised ITLPDGL, complete remission after relatively low-dose IFRT is promising, particularly as this has been rarely achieved by chemotherapy.

Prognostic impact of peripheral blood Wilms' tumour 1 mRNA expression levels in response to azacytidine in MDS: A single-centre analysis

To determine the impact of peripheral blood (PB) Wilms' tumour 1 (WT-1) mRNA levels in patients with primary myelodysplastic syndromes (MDS), we analysed the relationships between several clinical variables at the time of diagnosis and the haematological response of patients treated with azacytidine. We observed overall responses in 20 (63%) patients; there were no significant differences in clinical variables, including bone marrow blast counts, IPSS scores and IPSS-R risk scores, between responders and non-responders. The responders' PB WT-1 mRNA levels were significantly lower than those of non-responders (P = 0.03). PB WT-1 mRNA expression could be a marker for predicting the response to azacytidine in patients with de novo MDS.

Long-term outcomes and recurrence-free interval after the treatment of keloids with a standardized protocol

BACKGROUND

Recurrence rates of keloids have generally been reported at one time point. However, the longer the duration after treatment, the greater the likelihood that such lesions will recur. In this study, we analysed the time to recurrence during long-term follow-up.

MATERIAL AND METHODS

We retrospectively reviewed recurrence-free interval in 52 patients with keloid (age 8-79 years) who had been treated between June 2006 and January 2011 using a standardised protocol developed by our group.

RESULTS

Mean duration of follow-up was 37.5 (range, 7-120) months in patients with keloid. Kaplan-Meier survival curves revealed a statistically significant difference in recurrence-free interval between ear keloids and keloids excluding ear keloids. Recurrence rate for keloids was high in the first 2 years after treatment.

CONCLUSIONS

Kaplan-Meier analysis was useful for understanding the tendency of recurrence of keloids after treatment using a standardised protocol.

Effect of chest-compression-only bystander cardiopulmonary resuscitation on the likelihood of initial shockable rhythm after out-of-hospital cardiac arrest: a propensity matching analysis

Background/Introduction

Shockable rhythm after cardiac arrest is highly expected after early initiation of bystander cardiopulmonary resuscitation (CPR) owing to increased coronary perfusion. However, the relationship between bystander CPR and initial shockable rhythm in patients with out-of-hospital cardiac arrest (OHCA) remains unclear. We hypothesized that chest-compression-only CPR (CC-CPR) before emergency medical service (EMS) arrival has an equivalent effect on the likelihood of initial shockable rhythm to the standard CPR (chest compression plus rescue breathing [S-CPR]).

Purpose

We aimed to examine the rate of initial shockable rhythm and 1-month outcomes in patients who received bystander CPR after OHCA.

Methods

The study included 59,688 patients (age, ≥18 years) who received bystander CPR after an OHCA with a presumed cardiac origin witnessed by a layperson in a prospectively recorded Japanese nationwide Utstein-style database from 2013 to 2017. Patients who received public-access defibrillation before arrival of the EMS personnel were excluded. The patients were divided into CC-CPR (n=51,520) and S-CPR (n=8168) groups according to the type of bystander CPR received. The primary end point was initial shockable rhythm recorded by the EMS personnel just after arrival at the site. The secondary end point was the 1-month outcomes (survival and neurologically intact survival) after OHCA. In the statistical analyses, a Cox proportional hazards model was applied to reflect the different bystander CPR durations before/after propensity score (PS) matching.

Results

The crude rate of the initial shockable rhythm in the CC-CPR group (21.3%, 10,946/51,520) was significantly higher than that in the S-CPR group (17.6%, 1441/8168, p&lt;0.0001) before PS matching. However, no significant difference in the rate of initial shockable rhythm was found between the 2 groups after PS matching (18.3% [1493/8168] vs 17.6% [1441/8168], p=0.30). In the Cox proportional hazards model, CC-CPR was more negatively associated with the initial shockable rhythm before PS matching (unadjusted hazards ratio [HR], 0.97; 95% confidence interval [CI], 0.94–0.99; p=0.012; adjusted HR, 0.92; 95% CI, 0.89–0.94; p&lt;0.0001) than S-CPR. After PS matching, however, no significant difference was found between the 2 groups (adjusted HR of CC-CPR compared with S-CPR, 0.97; 95% CI, 0.94–1.00; p=0.09). No significant differences were found between C-CPR and S-CPR in the 1-month outcomes after PS matching as follows, respectively: survival, 8.5% and 10.1%; adjusted odds ratio, 0.89; 95% CI, 0.79–1.00; p=0.07; cerebral performance category 1 or 2, 5.5% and 6.9%; adjusted odds, 0.86; 95% CI, 0.74–1.00; p=0.052.

Conclusions

Compared with S-CPR, the CC-CPR before EMS arrival had an equivalent multivariable-adjusted association with the likelihood of initial shockable rhythm in the patients with OHCA due to presumed cardiac causes that was witnessed by a layperson.

Funding Acknowledgement

Type of funding source: None

Fluorescence optical imaging in patients with active rheumatoid arthritis: a comparison with ultrasound and an association with biomarkers

Objectives: This study compared indocyanine green (ICG)-enhanced fluorescence optical imaging (FOI) and musculoskeletal ultrasound (MSUS), and explored the significance of the FOI findings based on the association between the FOI and MSUS findings and serum biomarkers in patients with rheumatoid arthritis (RA). The study also explored the association between the FOI findings and patients' joint destruction at the joint-area level.Method: We enrolled 50 consecutive patients with active RA from among the patients hospitalized from May 2014 to March 2016 at Nagasaki University Hospital, Japan. FOI images were acquired with the Xiralite^® fluorescence imaging system and compared with the patients' clinical examination results and MSUS findings. On the same day, the patients' clinical disease activity and levels of serum biomarkers (including vascular endothelial growth factor) were obtained.Results: Although the FOI detected synovitis with high sensitivity, the frequency of positive findings and the diagnostic performance with MSUS as the reference standard for FOI differed considerably among the phases of FOI as well as among the affected joint regions. The FOI scores were positively correlated with clinical disease activity, MSUS scores, and serum biomarkers. The severity of FOI-proven synovitis was associated with the presence of MSUS-proven bone erosion.Conclusion: FOI is effective for detecting joint inflammation in RA patients, with high accuracy. The severity of the FOI score was closely associated with the joint destruction at the joint-area level. However, the significance of positive FOI findings differed depending on not only the phase of FOI but also the affected joint regions.

Effects of cigarette smoking and human T-cell leukaemia virus type 1 infection on anti-citrullinated peptide antibody production in Japanese community-dwelling adults: the Nagasaki Islands Study

Objectives: We investigated whether the positivity of anti-citrullinated peptide antibody (ACPA) is associated with cigarette-smoking status and human T-cell leukaemia virus type 1 (HTLV-1) infection in a general population in Nagasaki, Japan, which is an ageing and HTLV-1-endemic area.Method: Baseline data from community-dwelling people in the Nagasaki Islands Study (NaIS) were included in this cross-sectional analysis. ACPA and HTLV-1 were measured in 3887 subjects without a history of treatment for rheumatoid arthritis. A logistic regression analysis was performed to assess the relationship between ACPA positivity and candidates of correlation with ACPA, i.e. the cigarette-smoking status quantified by Brinkman's index (BI) and HTLV-1 positivity.Results: Fifty-one subjects (1.3%) showed ACPA positivity, and 650 subjects (16.6%) were HTLV-1 carriers. In an age- and gender-adjusted logistic regression analysis, the BI [odds ratio (OR) 1.09, 95% confidence interval (CI)1.02-1.14, p = 0.0031] and a BI value > 500 (OR 3.92, 95% CI 1.72-9.22, p = 0.0014) were each significantly associated with ACPA positivity. HTLV-1 positivity did not show any association with ACPA positivity.Conclusion: A significant effect of cigarette-smoking status on ACPA production was revealed, whereas HTLV-1 positivity was not associated with ACPA production in this general population.

[Therapy-related acute promyelocytic leukemia developing during chemotherapy for thymic carcinoma]

A 74-year-old man was admitted to hospital due to suspected acute leukemia. He had a history of thymic carcinoma, which had been treated with carboplatin in combination with either paclitaxel or amrubicin. However, the tumor remained unresponsive to these treatments. Administration of tegafur/gimeracil/oteracil (TS-1) was initiated, which resulted in tumor size reduction and a partial response. However, leukopenia persisted after the last TS-1 treatment, and four years after the initial treatment, increased blast cell counts were found in a blood film . Bone marrow analysis showed blasts with Auer rods, faggot cells, and dysplastic promyelocytes. Flow cytometry was positive for CD13, CD33, CD34, CD117, and myeloperoxidase, but negative for HLA-DR. PML-RARA fluorescence in situ hybridization was positive. Cytogenetic analysis revealed 47,XY,t (15;17) (q22;q21),+21. Thus, therapy-related acute promyelocytic leukemia (tAPL) was diagnosed. The patient achieved and maintained complete remission for more than 20 months by a de novo APL-treatment regimen including all-trans retinoic acid, arsenic trioxide and tamibarotene. Moreover, the thymic carcinoma has remained stable. Although secondary malignancies of thymic carcinoma have been previously reported, therapy-related leukemia, especially tAPL, is very rare.

AB0089 THE ANALYSIS FOR THE INHIBITION OF ANGIOGENESIS BY JAK INHIBITOR

Background:

Many blood vessels are generated in the hyperplastic synovial tissue of patients with rheumatoid arthritis (RA), and lead to chronic tissue inflammation and joint destruction [1]. Janus kinase (JAK) family consisting of JAK1, JAK2, JAK3 and tyrosine kinase 2 (TYK2) are chain receptors which phosphorylate signal transducers and activators of transcription (STAT) and mediate inflammatory diseases including RA [2]. Nowadays, several JAK inhibitors such as Tofacitinib (TOF), Baricitinib (BAR) and Peficitinib (PEF) have been developed and demonstrated to have the inhibitory effects on inflammatory arthritis [3-5]. However, there were few reports concerning their effects on angiogenesis in vitro.

Objectives:

The purpose of the present study is to investigate the influence of JAK inhibitors on angiogenesis of human umbilical vein endothelial cell (HUVEC) activated by vascular endothelial growth factor (VEGF).

Methods:

The cell line of HUVECs were used for this study. The activity of proliferation and tube formation were analyzed by counting assay and tube formation assay, respectively.

In counting assay, HUVECs (5 × 104cells/ml) were seeded onto 96-well cell culture plate with 20 ng/ml VEGF including various doses (0.1µM, 1µM, 5µM) of TOF, BAR or PEF. After 48 hours incubation at 37°C in a humidified atmosphere containing 5% CO2, cell proliferation of each groups was assessed using cell counting kit. In tube formation assay, HUVECs (5 × 104cells/ml) were treated with 20ng/ml VEGF including various dose (0.1µM, 1µM, 5µM) of TOF, BAR or PEF for 00 hours, then seeded onto 48-well plate applied with Matrigel. After 24 hours incubation on Matrigel, the capillary-like tube formation of each well was photographed using phase contrast microscopy. Tube formation were quantitated by measurement of the length of branch.

Results:

HUVECs were activated in proliferation and tube formation by VEGF treatment. And, the proliferation and tube formation of HUVECs activated by VEGF were suppressed by All of TOF, BAR and PEF. In particular, TOF and PEF could suppress them highly.

Conclusion:

This study showed the inhibitory effect of JAK inhibitors on proliferation and tube formation of HUVECs activated by VEGF. In particular, the angiogenesis of HUVECs activated by VEGF was highly suppressed by TOF and PEF. VEGF is reported to regulate the angiogenesis through multi JAK-STAT signaling pathways [6]. The inhibitory effects on angiogenesis of TOF, BAR and PEF might depend on the differences in their affinity for JAKs. VEGF has been shown to a have a central involvement in the angiogenic process in RA [7]. JAK inhibitors might suppress the angiogenesis in RA synovial tissues by inhibiting VEGF signaling.

References:

[1]Scott DL, et al. Rheumatoid arthritis. Lancet. 2010.

[2]Banerjee S, et al. JAK-STAT signaling as a target for inflammatory and autoimmune diseases: current and future prospects. Drugs. 2017.

[3]William D, et al. JAK inhibitors in dermatology: the promise of a new drug class. Journal of the American Academy of Dermatology. 2017.

[4]Dhillon S. Tofacitinib: A Review in Rheumatoid Arthritis. Drugs. 2017.

[5]Markham A, et al. Peficitinib: First Global Approval. Drugs. 2019.

[6]Zhang HY, et al. Three important components in the regeneration of the cavernous nerve: brain-derived neurotrophic factor, vascular endothelial growth factor and the JAK/STAT signaling pathway. Asian journal of andrology. 2011.

[7]Paleolog EM. Angiogenesis in rheumatoid arthritis. Arthritis research. 2002.

Acknowledgments:

none

Disclosure of Interests:

None declared

AB1232 ORAL DYSBIOSIS REFLECTS THE IMMUNOLOGICAL ALTERATION OF RA REGARDING TO ACPA AND HLA DRB1*SE: NAGASAKI ISLAND STUDY

Background:

Anti-citrullinated protein antibody (ACPA) production is observed in several organs even prior to the onset of rheumatoid arthritis (RA), and oral mucosa is considered to be one of the important tissues. The presence of HLA-DRB1*SE closely associates with ACPA production. Saliva is considered to reflect the oral microbiota including periodontal disease. Alteration of oral microbiota of RA becomes to be normalized by DMARDs treatment, however, the interaction of HLA-DRB1*SE, ACPA and oral microbiota of RA patients remains to be elucidated.

Objectives:

The Nagasaki Island Study, which had started in 2014 collaborating with Goto City, is intended for research of the preclinical stage of RA, including ACPA/HLA genotype screening and ultrasound and magnetic resonance imaging examinations in high-risk subjects. Using the samples accumulated in this cohort, we have tried to investigate the difference of oral microbiota among RA patients and healthy subjects regarding to ACPA and HLA-DRB1*SE.

Methods:

Blood and salivary samples were obtained from 1422 subjects out of 4276 who have participated in the Nagasaki Island Study from 2016 to 2018. ACPA positivity was 1.7 % in total. Some of RA patients resided in Goto City participated in the Nagasaki Island Study. At this point, we selected 291 subjects, who were ACPA positive non-RA healthy subjects (n=22) and patients with RA (n=33, 11 subjects were ACPA positive and 22 ACPA negative respectively) as the case, age and gender matched ACPA negative non-RA healthy subjects (n=236) as the control. ACPA was measured by an enzyme-linked immunosorbent assay, and HLA genotyping was quantified by next-generation sequencing (Ref.1). The operational taxonomic unit (OUT) analysis using 16S rRNA gene sequencing were performed. The richness of microbial diversity within-subject (alpha diversity) was scaled via Shannon entropy. The dissimilarity between microbial community composition was calculated using Bray-Curtis distance as a scale, and differences between groups (beta diversity) were tested by permutational multivariate analysis of variance (PERMANOVA). In addition, UniFrac distance calculated in consideration of the distance on the phylogenetic tree were performed.

Results:

Median age 70 y.o., % Female 58.8 %. Among RA and non-RA subjects, not alpha diversity but beta diversity was statistically significance (p=0.022, small in RA). In RA subjects, both alpha and beta diversity is small (p<0.0001), especially significant in ACPA positive RA (Figure 1). Amongt RA subjects, presence of HLA-DRB1*SE did not show the difference but the tendency of being small of alpha diversity (p=0.29).

Conclusion:

Our study has suggested for the first time the association of oral microbiota alteration with the presence of ACPA and HLA-DRB1*SE. Oral dysbiosis may reflect the immunological status of patients with RA.

References:

[1]Kawaguchi S, et al. Methods Mol Biol 2018;1802: 22

Disclosure of Interests:

None declared

P492Estimation of no-flow duration and survival in patients with an initial shockable rhythm after out-of-hospital cardiac arrest

Funding Acknowledgements

Japan Society for the Promotion of Science (KAKENHI Grant No. 18K09999)

Background

In patients with unwitnessed out-of-hospital cardiac arrest (OHCA), the actual no-flow duration (the time with no organ perfusion) is unclear. However, when these patients have a shockable rhythm as an initial recorded rhythm, the no-flow duration may be relatively short as compared with other initial rhythms, and some patients can obtain a good functional outcome after OHCA.

Purpose

The purpose of the present study was to estimate the no-flow duration and to determine the relationship between no-flow duration and neurologically intact survival in patients with an initial shockable rhythm after OHCA.

Methods

We reviewed 82,464 patients with OHCA (aged ≥18 years, non-traumatic, witnessed, and without any bystander interventions) who were included in the All-Japan Utstein-style registry from 2013 to 2017. The study end point was 1-month neurologically intact survival (Cerebral Performance Category scale 1 or 2). No-flow duration was defined as the time from emergency call to emergency medical services (EMS) arrival at the patient site.

Results

The rate of 1-month neurologically intact survival in the patients with an initial shockable rhythm (n = 10,384, 12.6% of overall patients) was 16.5% (1718/10,384). No-flow duration was significantly and inversely associated with 1-month neurologically intact survival (adjusted odds ratios for 1-minute increments: 0.85, 95% confidence interval: 0.84–0.86). The proportion of patients with a shockable rhythm to the overall patients (y, %) had a high correlational relationship with no-flow duration (x, min), depicted by y = 21.0 - 0.95 × x, R² = 0.935. In this analytical model, the number of patients with shockable rhythm reached null at 22 minutes of no-flow duration. The no-flow durations, beyond which the chance for initial shockable rhythm diminished to &lt;10%, &lt;5%, and &lt;1%, were 12, 13, and 17 minutes, respectively. The rate of neurologically intact survival in the patients with shockable rhythm (y, %) and no-flow duration (x, min) were also found to have a strong correlation, depicted by y = 0.16 × x² - 5.12 × x + 45.0, R² = 0.907. The no-flow durations, beyond which the chance for 1-month neurologically intact survival diminished to &lt;10%, &lt;5%, and &lt;1%, were 10, 11, and 15 minutes, respectively.

Conclusions

In OHCA patients without any bystander interventions before EMS personnel arrival, when a shockable rhythm is recorded by EMS personnel as an initial rhythm, the no-flow duration after cardiac arrest is highly likely to be &lt;17 minutes regardless of the layperson witness status. The limitation of no-flow duration to obtain a 1-month neurologically intact survival after OHCA may be 15 minutes when the patients have an initial shockable rhythm.

P498External validation of a field termination-of-resuscitation rule for refractory out-of-hospital cardiac arrests in Japan

Background

A universal basic life support termination-of-resuscitation (BLS-TOR) rule was developed to identify patients with out-of-hospital cardiac arrest (OHCA) eligible for field termination of cardiopulmonary resuscitation (CPR). In Japan, however, emergency medical service (EMS) providers are not allowed field termination of CPR and must transport all patients with OHCA to hospitals, regardless of return of spontaneous circulation (ROSC). Therefore, we previously developed a Japanese TOR (JP-TOR) rule in the field for refractory OHCAs using data from the All-Japan Utstein registry between 2011 and 2015, when CPR was performed according to the 2010 guidelines. The JP-TOR rule recommends CPR termination when patients meet all the following criteria: initial asystole, unwitnessed arrest, age ≥81 years, no bystander interventions before EMS arrival, and no ROSC after EMS-initiated CPR for 14 min.

Purpose

To validate the JP-TOR rule using more recent data where CPR was performed according to the 2015 guidelines, comparing the relevance of JP-TOR rule with the BLS-TOR rule, which consists of the following criteria: no prehospital ROSC after 6-min EMS-initiated CPR, arrest unwitnessed by EMS providers, and no shock received.

Methods

We analysed the records of 242,184 patients (age ≥18 years) who experienced OHCA treated by EMS providers. Data were obtained from a prospectively recorded Japanese nationwide Utstein-style database from 2016 to 2017. The primary endpoints were specificity and positive predictive value (PPV) for predicting the 1-month mortality after OHCA with the JP-TOR and BLS-TOR rules.

Results

The overall 1-month survival rate was 5.3% (12,847/242,184). The proportions of patients with OHCA fulfilled the JP-TOR and BLS-TOR criteria were 10.4% and 89.3%, respectively. The specificity and PPV of the JP-TOR and BLS-TOR rules for predicting 1-month mortality were 99.5% (95% confidence interval [CI], 99.4%–99.5%) and 99.8% (95% CI, 99.7%–99.8%) and 44.7% (95% CI, 43.8%–45.5%) and 96.7% (95% CI, 96.6%–96.8%), respectively.

Conclusions

The JP-TOR rule for EMS providers treating patients with OHCA in the field was successfully validated using more recent data from a Japanese registry where CPR was performed according to the 2015 guidelines. The JP-TOR rule was superior to the BLS-TOR rule in Japanese EMS systems, having both high specificity and PPV of &gt;99% for predicting 1-month mortality. The JP-TOR rule may help EMS providers decide whether to terminate resuscitation efforts for unresuscitable patients with OHCA in the field. Prospective validation studies and establishment of prehospital EMS protocol are required before implementing this rule in Japan.