Application of MicroResp™ for quick and easy detection of plastic degradation by marine bacterial isolates

Microplastic debris in the marine environment is a global problem. Biodegradable polymers are being developed as alternatives to petroleum-based plastics, and quick and easy methods for screening for bacterial strains that can degrade such polymers are needed. As a screening method, the clear zone method has been widely used but has technical difficulties such as plate preparation and interpretation of results. In this study, we adapted the MicroResp™ system to easily detect biodegradation activity of marine bacteria in a 3-day assay. Among the 6 bacterial strains tested, 3, 2 and 1 strain degraded poly (butylene succinate-co-adipate) (PBSA), poly (ε-caprolactone) (PCL) and poly (3-hydroxybutyrate-co-3-hydroxyhexanoate), respectively. Only one strain that showed degradation activity of PBSA and PCL in the MicroResp™ system was also positive in the clear zone assay on the respective emulsion plates. Our results show that the adapted MicroResp™ system can screen for bacterial strains that degrade plastic.

Microbial decomposition of biodegradable plastics on the deep-sea floor

Microbes can decompose biodegradable plastics on land, rivers and seashore. However, it is unclear whether deep-sea microbes can degrade biodegradable plastics in the extreme environmental conditions of the seafloor. Here, we report microbial decomposition of representative biodegradable plastics (polyhydroxyalkanoates, biodegradable polyesters, and polysaccharide esters) at diverse deep-sea floor locations ranging in depth from 757 to 5552 m. The degradation of samples was evaluated in terms of weight loss, reduction in material thickness, and surface morphological changes. Poly(L-lactic acid) did not degrade at either shore or deep-sea sites, while other biodegradable polyesters, polyhydroxyalkanoates, and polysaccharide esters were degraded. The rate of degradation slowed with water depth. We analysed the plastic-associated microbial communities by 16S rRNA gene amplicon sequencing and metagenomics. Several dominant microorganisms carried genes potentially encoding plastic-degrading enzymes such as polyhydroxyalkanoate depolymerases and cutinases/polyesterases. Analysis of available metagenomic datasets indicated that these microorganisms are present in other deep-sea locations. Our results confirm that biodegradable plastics can be degraded by the action of microorganisms on the deep-sea floor, although with much less efficiency than in coastal settings.

Blautia parvula sp. nov., isolated from Japanese faecal samples

Two Gram-positive, anaerobic, non-spore-forming and coccoid or oval-shaped bacterial strains, namely, DN0138T and DN0266, were isolated from faecal samples of healthy Japanese people. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain DN0138T clustered with a species of the genus Blautia and was closely related to Blautia producta JCM 1471T, Blautia coccoides JCM 1395T, Blautia hominis KB1T and 'Blautia marasmi' Marseille-P2377, with sequence similarities of 98.6, 98.5, 98.8 and 98.2 %, respectively. The average nucleotide identity values were 85.3 % for B. producta JCM 1471T, 85.0 % for B. coccoides NCTC 11035T, 84.3 % for B. hominis KB1T and 84.3 % for 'B. marasmi' Marseille-P2377. The major end products of glucose metabolism were acetic acid, lactic acid and succinic acid. The genome length of strain DN0138T was 6 247 046 bp with 46.7 mol% G+C content of genome sequence. Based on their phenotypic, cellular fatty acid and phylogenetic characteristics, the three isolates represent a novel species within the genus Blautia, for which the name Blautia parvula sp. nov. is proposed. The type strain is DN0138T (=NBRC 113351T=BCRC 81349T).

RENEB Inter-Laboratory Comparison 2021: Inter-Assay Comparison of Eight Dosimetry Assays

Tools for radiation exposure reconstruction are required to support the medical management of radiation victims in radiological or nuclear incidents. Different biological and physical dosimetry assays can be used for various exposure scenarios to estimate the dose of ionizing radiation a person has absorbed. Regular validation of the techniques through inter-laboratory comparisons (ILC) is essential to guarantee high quality results. In the current RENEB inter-laboratory comparison, the performance quality of established cytogenetic assays [dicentric chromosome assay (DCA), cytokinesis-block micronucleus assay (CBMN), stable chromosomal translocation assay (FISH) and premature chromosome condensation assay (PCC)] was tested in comparison to molecular biological assays [gamma-H2AX foci (gH2AX), gene expression (GE)] and physical dosimetry-based assays [electron paramagnetic resonance (EPR), optically or thermally stimulated luminescence (LUM)]. Three blinded coded samples (e.g., blood, enamel or mobiles) were exposed to 0, 1.2 or 3.5 Gy X-ray reference doses (240 kVp, 1 Gy/min). These doses roughly correspond to clinically relevant groups of unexposed to low exposed (0-1 Gy), moderately exposed (1-2 Gy, no severe acute health effects expected) and highly exposed individuals (>2 Gy, requiring early intensive medical care). In the frame of the current RENEB inter-laboratory comparison, samples were sent to 86 specialized teams in 46 organizations from 27 nations for dose estimation and identification of three clinically relevant groups. The time for sending early crude reports and more precise reports was documented for each laboratory and assay where possible. The quality of dose estimates was analyzed with three different levels of granularity, 1. by calculating the frequency of correctly reported clinically relevant dose categories, 2. by determining the number of dose estimates within the uncertainty intervals recommended for triage dosimetry (±0.5 Gy or ±1.0 Gy for doses <2.5 Gy or >2.5 Gy), and 3. by calculating the absolute difference (AD) of estimated doses relative to the reference doses. In total, 554 dose estimates were submitted within the 6-week period given before the exercise was closed. For samples processed with the highest priority, earliest dose estimates/categories were reported within 5-10 h of receipt for GE, gH2AX, LUM, EPR, 2-3 days for DCA, CBMN and within 6-7 days for the FISH assay. For the unirradiated control sample, the categorization in the correct clinically relevant group (0-1 Gy) as well as the allocation to the triage uncertainty interval was, with the exception of a few outliers, successfully performed for all assays. For the 3.5 Gy sample the percentage of correct classifications to the clinically relevant group (≥2 Gy) was between 89-100% for all assays, with the exception of gH2AX. For the 1.2 Gy sample, an exact allocation to the clinically relevant group was more difficult and 0-50% or 0-48% of the estimates were wrongly classified into the lowest or highest dose categories, respectively. For the irradiated samples, the correct allocation to the triage uncertainty intervals varied considerably between assays for the 1.2 Gy (29-76%) and 3.5 Gy (17-100%) samples. While a systematic shift towards higher doses was observed for the cytogenetic-based assays, extreme outliers exceeding the reference doses 2-6 fold were observed for EPR, FISH and GE assays. These outliers were related to a particular material examined (tooth enamel for EPR assay, reported as kerma in enamel, but when converted into the proper quantity, i.e. to kerma in air, expected dose estimates could be recalculated in most cases), the level of experience of the teams (FISH) and methodological uncertainties (GE). This was the first RENEB ILC where everything, from blood sampling to irradiation and shipment of the samples, was organized and realized at the same institution, for several biological and physical retrospective dosimetry assays. Almost all assays appeared comparably applicable for the identification of unexposed and highly exposed individuals and the allocation of medical relevant groups, with the latter requiring medical support for the acute radiation scenario simulated in this exercise. However, extreme outliers or a systematic shift of dose estimates have been observed for some assays. Possible reasons will be discussed in the assay specific papers of this special issue. In summary, this ILC clearly demonstrates the need to conduct regular exercises to identify research needs, but also to identify technical problems and to optimize the design of future ILCs.

RENEB Inter-Laboratory Comparison 2021: The FISH-Based Translocation Assay

Translocation analysis using fluorescence in situ hybridization (FISH) is the method of choice for dose assessment in case of chronic or past exposures to ionizing radiation. Although it is a widespread technique, unlike dicentrics, the number of FISH-based inter-laboratory comparisons is small. For this reason, although the current Running the European Network of Biological and Physical retrospective Dosimetry (RENEB) inter-laboratory comparison 2021 was designed as a fast response to a real emergency scenario, it was considered a good opportunity to perform an inter-laboratory comparison using the FISH technique to gain further experience. The Bundeswehr Institute of Radiobiology provided peripheral blood samples from one healthy human volunteer. Three test samples were irradiated with blinded doses of 0, 1.2, and 3.5 Gy, respectively. Samples were then sent to the seven participating laboratories. The FISH technique was applied according to the standard procedure of each laboratory. Both, the frequency of translocations and the estimated dose for each sample were sent to the coordinator using a special scoring sheet for FISH. All participants sent their results in due time. However, although it was initially requested to send the results based on the full analysis, evaluating 500 equivalent cells, most laboratories only sent the results based on triage, with a smaller number of analyzed cells. In the triage analysis, there was great heterogeneity in the number of equivalent cells scored. On the contrary, for the full analysis, this number was more homogeneous. For all three samples, one laboratory showed outlier yields compared to the other laboratories. Excluding these results, in the triage analysis, the frequency of translocations in sample no. 1 ranged from 0 to 0.013 translocations per cell, and for samples no. 2 and no. 3 the genomic mean frequency were 0.27 ± 0.03 and 1.47 ± 0.14, with a coefficient of variation of 0.29 and 0.23 respectively. Considering only results obtained in the triage analysis for sample no. 1, all laboratories, except one, classified this sample as the non-irradiated one. For sample no. 2, excluding the outlier value, the mean reported dose was 1.74 ± 0.16 Gy indicating a mean deviation of about 0.5 Gy to the delivered dose of 1.2 Gy. For sample no. 3 the mean dose estimated was 4.21 ± 0.21 Gy indicating a mean deviation of about 0.7 Gy to the delivered dose of 3.5 Gy. In the frame of RENEB, this is the second FISH-based inter-laboratory comparison. The whole exercise was planned as a response to an emergency, therefore, a triage analysis was requested for all the biomarkers except for FISH. Although a full analysis was initially requested for FISH, most of the laboratories reported only a triage-based result. The main reason is that it was not clearly stated what was required before starting the exercise. Results show that most of the laboratories successfully discriminated unexposed and irradiated samples from each other without any overlap. A good agreement in the observed frequencies of translocations was observed but there was a tendency to overestimate the delivered doses. Efforts to improve the harmonization of this technique and subsequent exercises to elucidate the reason for this trend should be promoted.

RENEB Inter-Laboratory Comparison 2021: The Dicentric Chromosome Assay

After large-scale radiation accidents where many individuals are suspected to be exposed to ionizing radiation, biological and physical retrospective dosimetry assays are important tools to aid clinical decision making by categorizing individuals into unexposed/minimally, moderately or highly exposed groups. Quality-controlled inter-laboratory comparisons of simulated accident scenarios are regularly performed in the frame of the European legal association RENEB (Running the European Network of Biological and Physical retrospective Dosimetry) to optimize international networking and emergency readiness in case of large-scale radiation events. In total 33 laboratories from 22 countries around the world participated in the current RENEB inter-laboratory comparison 2021 for the dicentric chromosome assay. Blood was irradiated in vitro with X rays (240 kVp, 13 mA, ∼75 keV, 1 Gy/min) to simulate an acute, homogeneous whole-body exposure. Three blood samples (no. 1: 0 Gy, no. 2: 1.2 Gy, no. 3: 3.5 Gy) were sent to each participant and the task was to culture samples, to prepare slides and to assess radiation doses based on the observed dicentric yields from 50 manually or 150 semi-automatically scored metaphases (triage mode scoring). Approximately two-thirds of the participants applied calibration curves from irradiations with γ rays and about 1/3 from irradiations with X rays with varying energies. The categorization of the samples in clinically relevant groups corresponding to individuals that were unexposed/minimally (0-1 Gy), moderately (1-2 Gy) or highly exposed (>2 Gy) was successfully performed by all participants for sample no. 1 and no. 3 and by ≥74% for sample no. 2. However, while most participants estimated a dose of exactly 0 Gy for the sham-irradiated sample, the precise dose estimates of the samples irradiated with doses >0 Gy were systematically higher than the corresponding reference doses and showed a median deviation of 0.5 Gy (sample no. 2) and 0.95 Gy (sample no. 3) for manual scoring. By converting doses estimated based on γ-ray calibration curves to X-ray doses of a comparable mean photon energy as used in this exercise, the median deviation decreased to 0.27 Gy (sample no. 2) and 0.6 Gy (sample no. 3). The main aim of biological dosimetry in the case of a large-scale event is the categorization of individuals into clinically relevant groups, to aid clinical decision making. This task was successfully performed by all participants for the 0 Gy and 3.5 Gy samples and by 74% (manual scoring) and 80% (semi-automatic scoring) for the 1.2 Gy sample. Due to the accuracy of the dicentric chromosome assay and the high number of participating laboratories, a systematic shift of the dose estimates could be revealed. Differences in radiation quality (X ray vs. γ ray) between the test samples and the applied dose effect curves can partly explain the systematic shift. There might be several additional reasons for the observed bias (e.g., donor effects, transport, experimental conditions or the irradiation setup) and the analysis of these reasons provides great opportunities for future research. The participation of laboratories from countries around the world gave the opportunity to compare the results on an international level.

Arthrobacter mangrovi sp. nov., an actinobacterium isolated from the rhizosphere of a mangrove

A novel actinobacterium, designated HIs16-36^T, was isolated from the rhizosphere of a mangrove on Ishigaki Island, Okinawa, Japan, and its taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain HIs16-36^T was closely related to the members of the genus Arthrobacter. The highest 16S rRNA gene sequence similarity was observed with Arthrobacter crystallopoietes (98.5 %), followed by Arthrobacter globiformis (97.2 %). The peptidoglycan of strain HIs16-36^T was of the A4α type, with lysine as the diagnostic diamino acid. The predominant isoprenoid quinone was MK-9(H₂) and the major fatty acids were anteiso-C_15 : 0 and iso-C_15 : 0. The polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and two glycolipids. These chemotaxonomic features corresponded to those of the genus Arthrobacter. Meanwhile, the differences in some phenotypic characteristics, along with the results of average nucleotide identity and digital DNA-DNA hybridization analyses, indicated that strain HIs16-36^T should be distinguished from the recognized species of the genus Arthrobacter. Therefore, strain HIs16-36^T represents a novel species of the genus Arthrobacter, for which the name Arthrobacter mangrovi sp. nov. is proposed. The type strain is HIs16-36^T (=NBRC 112813^T=TBRC 15750^T).

Effects of prior osteoporosis treatment on the treatment response of romosozumab followed by denosumab in patients with postmenopausal osteoporosis

In patients with postmenopausal osteoporosis, prior osteoporosis treatment affected the bone mineral density increase of following treatment with 12 months of romosozumab, although it did not affect that of following treatment with 12 months of denosumab after romosozumab.

PURPOSE

To investigate the effects of prior osteoporosis treatment on the response to treatment with romosozumab (ROMO) followed by denosumab (DMAb) in patients with postmenopausal osteoporosis.

METHODS

In this prospective, observational, multicenter study, treatment-naïve patients (Naïve; n = 55) or patients previously treated with bisphosphonates (BP; n = 37), DMAb (DMAb; n = 45) or teriparatide (TPTD; n = 17) (mean age, 74.6 years; T-scores of the lumbar spine [LS] - 3.2 and total hip [TH] - 2.6) were switched to ROMO for 12 months, followed by DMAb for 12 months. Bone mineral density (BMD) and serum bone turnover markers were evaluated for 24 months.

RESULTS

A BMD increase was observed at 12 and 24 months in the following patients: Naïve (18.2% and 22.0%), BP (10.2% and 12.1%), DMAb (6.6% and 9.7%), and TPTD (10.8% and 15.0%) (P < 0.001 between the groups at both 12 and 24 months) in LS and Naïve (5.5% and 8.3%), BP (2.9% and 4.1%), DMAb (0.6% and 2.2%), and TPTD (4.3% and 5.4%) (P < 0.01 between the groups at 12 months and P < 0.001 at 24 months) in TH, respectively. The BMD increase in LS from 12 to 24 months was negatively associated with the levels of bone resorption marker at 24 months. Incidences of major fragility fractures for the respective groups were as follows: Naïve (5.5%), BP (16.2%), DMAb (11.1%), and TPTD (5.9%).

CONCLUSIONS

Previous treatment affected the BMD increase of following treatment with ROMO, although it did not affect that of following treatment with DMAb after ROMO.

Biodiversity risk assessment of genetically modified Chaetoceros gracilis for outdoor cultivation

A genetically modified (GM) strain of the diatom Chaetoceros gracilis expressing the phosphite dehydrogenase gene (ptxD), which is a useful gene both for the biological containment and the avoidance of microbial contamination, was characterized to estimate the risk against the biodiversity by laboratory experiments. GM strain could grow in the medium containing phosphite as a sole source of phosphorus, while its general characteristics such as growth, salt tolerance, heat and dehydration resistance in the normal phosphate-containing medium were equivalent to those of wild type (WT) strain. The increase in potential toxicity of GM strain against plant, crustacean, fish and mammal was also disproved. The dispersal ability of WT strain cultured in an outdoor raceway pond was investigated for 28 days by detecting the psb31 gene in vessels, settled at variable distances (between 5 and 60 m) from the pond. The diatom was detected only in one vessel placed 5 m apart. To estimate the influence on the environment, WT and GM strains were inoculated into freshwater, seawater and soil. The influence on the microbiome in those samples was assessed by 16S rRNA gene amplicon sequencing, in addition to the analysis of the survivability of those strains in the freshwater and the seawater. The results indicated that the effect to the microbiome and the survivability were comparable between WT and GM strains. All results showed that the introduction of the ptxD gene into the diatom had a low risk on biodiversity.

Influence of concurrent and staggered dosing of semi-solid nutrients on the pharmacokinetics of orally administered carbamazepine in rats

In the present study, we examined the effects of concurrent and staggered dosing of PG-soft ace-MP TM (PG), novel semi-solid enteral nutrients, on the pharmacokinetics of orally administered carbamazepine (CBZ) in rats due to the high possibility of drug interaction during the absorption process. The pharmacokinetic behavior of CBZ was considerably altered when administered concurrently with PG. The maximum serum CBZ concentration (C_max) significantly decreased and the mean residence time (MRT) significantly increased. The elimination constant (k_e) also significantly increased, but there were no significant changes in the area under the serum CBZ concentration versus time curve (AUC) and the time to reach C_max (T_max). However, these changes in the pharmacokinetic parameters were eliminated by waiting 20 min, the time interval equivalent to the T_max described above, between CBZ administration and PG dosing. This study suggested that PG interferes with CBZ absorption from the digestive tract, although staggered administration of CBZ and PG prevented their interaction.

Immunoglobulin A-specific deficiency induces spontaneous inflammation specifically in the ileum

OBJECTIVE

Although immunoglobulin A (IgA) is abundantly expressed in the gut and known to be an important component of mucosal barriers against luminal pathogens, its precise function remains unclear. Therefore, we tried to elucidate the effect of IgA on gut homeostasis maintenance and its mechanism.

DESIGN

We generated various IgA mutant mouse lines using the CRISPR/Cas9 genome editing system. Then, we evaluated the effect on the small intestinal homeostasis, pathology, intestinal microbiota, cytokine production, and immune cell activation using intravital imaging.

RESULTS

We obtained two lines, with one that contained a <50 base pair deletion in the cytoplasmic region of the IgA allele (IgA tail-mutant; IgA^tm/tm) and the other that lacked the most constant region of the IgH α chain, which resulted in the deficiency of IgA production (IgA^-/-). IgA^-/- exhibited spontaneous inflammation in the ileum but not the other parts of the gastrointestinal tract. Associated with this, there were significantly increased lamina propria CD4⁺ T cells, elevated productions of IFN-γ and IL-17, increased ileal segmented filamentous bacteria and skewed intestinal microflora composition. Intravital imaging using Ca²⁺ biosensor showed that IgA^-/- had elevated Ca²⁺ signalling in Peyer's patch B cells. On the other hand, IgA^tm/tm seemed to be normal, suggesting that the IgA cytoplasmic tail is dispensable for the prevention of the intestinal disorder.

CONCLUSION

IgA plays an important role in the mucosal homeostasis associated with the regulation of intestinal microbiota and protection against mucosal inflammation especially in the ileum.

Barthel Index score predicts mortality in elderly heart failure: a goal of comprehensive cardiac rehabilitation

Background

Accurate prediction of mortality in heart failure (HF) patients is crucial for decision-making regarding HF therapies, but a strategy for the prediction of mortality in elderly HF patients has not been established. In addition, although favorable effects of comprehensive cardiac rehabilitation (CR) on clinical outcomes and functional status in HF patients have been demonstrated, a goal of comprehensive CR during hospitalization for reducing mortality remains unclear.

Aims

We examined whether assessment of basic activities of daily living (ADL) by the Barthel Index (BI), the most widely used tool for assessment of basic ADL, is useful for predicting all-cause mortality in elderly HF patients who received comprehensive CR.

Methods

This study was a single-center, retrospective and observational study. We retrospectively examined 413 HF patients aged ≥65 years (mean age, 78±7 years; 50% female) who were admitted to our institute for management of HF and received comprehensive CR during hospitalization. Functional status for performing basic ADL ability was assessed by the BI within 3 days before discharge. The clinical endpoint was all-cause death during the follow-up period.

Results

Of 413 HF patients, 116 patients (28%) died during a follow-up period of median 1.90-years (interquartile range, 1.20–3.23 years). Results of an adjusted dose-dependent association analysis showed that the hazard ratio (HR) of mortality increases in an almost linear fashion as the BI score decreases and that the BI score corresponding the hazard ratio of 1.0 is 85 (Figure A). To minimize the differences in potential confounding factors between patient with low BI (&lt;85) and patients with high BI (≥85), inverse probability treatment weighting (IPTW) was calculated using propensity score. Kaplan-Meier survival curves, in which selection bias was minimized by use of IPTW for confounders, showed that patients with low BI (&lt;85) had a higher mortality rate than did patients with high BI (≥85) (Figure B). In multivariate Cox regression analyses, low BI was independently associated with higher mortality after adjustment for predictors including brain natriuretic peptide and prior HF hospitalization (IPTW-adjusted HR, 1.75 [95% confidence interval, 1.03–2.98], p&lt;0.001). Inclusion of the BI into the adjustment model improved the accuracy of prediction of mortality (continuous net reclassification improvement, 0.292, p=0.008; integrated discrimination improvement, 0.017, p=0.022).

Conclusion

A BI score of &lt;85 at the time of discharge is associated with increased mortality independently of known prognostic markers, and achievement of functional status of a BI score ≥85 by comprehensive CR during hospitalization may contribute to a favorable outcome in elderly HF patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the Japan Society for the Promotion of Science

Intracellular localization of AMP deaminase and its novel role in BCAA and lipid metabolism in diabetic cardiomyopathy

Background

A metabolomic study in the human heart suggested a pivotal role of amino acid (AA) metabolism in fatty acid oxidation, which is dysregulated in type 2 diabetes mellitus (T2DM) and heart failure. We previously reported that aberrant up-regulation of AMP deaminase 3 (AMPD3) impairs cardiac energetics in T2DM hearts, and AMPD3 was recently shown to be activated by fasting and to promote AA metabolism and fatty acid oxidation in skeletal muscle. A sodium glucose cotransporter 2 inhibitor (SGLT2i) has been shown to augment systemic AA metabolism, but its effect on cardiac AA metabolism remains unknown.

Purpose

We hypothesized that AMPD3 has a role in AA and lipid metabolism in cardiomyocytes and that the protective effect of an SGLT2i in diabetic hearts is mediated by modification of AA and lipid metabolism.

Methods and results

Proteomic analyses of AMPD3 immunoprecipitates in rat hearts revealed that AMPD3 interacted with the E1α and E2 components of the BCKDH complex, a rate-limiting enzyme of branched-chain AA (BCAA) catabolism. Immunoblotting using subcellular fractions revealed that BCKDH localized not only in the mitochondria matrix but also in the cytosol and endoplasmic reticulum (ER) and that AMPD3 interacted with BCKDH in the cytosol and ER. Despite comparable expression of BCKDH components and phosphorylation of E1α at Ser293, significant accumulation of BCAA was observed in T2DM rats (OLETF; 317±30 nmol/g) compared to that in control rats (LETO; 213±16 nmol/g), and the accumulation of BCAA was accompanied by up-regulation of AMPD3 in the cytosol and ER by 98% and 231%, respectively. In cardiomyocytes, disruption of BCAA catabolism by knockdown of BCKDH-E1α resulted in a 5.8-fold increase in AMPD3 at the transcriptional level and blunted lipid droplet biogenesis in response to a long-chain fatty acid challenge. Next, myocardial infarction (MI) was induced in LETO and OLETF pretreated with empagliflozin (10 mg/kg/day, 14 days) or a vehicle. Pathway analysis of cardiac metabolites revealed arginine biosynthesis and BCAA metabolism as the most significantly changed pathways with empagliflozin, with BCAA (791±187 nmol/g), glutamate, glutamine and urea being significantly increased. Empagliflozin restored myocardial ATP and survival after MI in OLETF to levels comparable to those in LETO. Electron microscopy showed a significantly higher prevalence of myocardium lipid droplets in OLETF, which was further increased by empagliflozin.

Conclusions

The results support the hypotheses that imbalance of extra-mitochondrial AMPD3-BCKDH interaction underlies dysregulated BCAA metabolism in T2DM hearts and that activation of cardiac AA metabolism by an SGLT2i normalizes fatty acid overload through sequestration into intracellular lipid droplets.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Boehringer Ingelheim

Is GLP-1 insufficiency a coronary risk factor? A multicenter observational study, BOREAS-CAD2

Background and aim

Glucagon-like peptide-1 (GLP-1) regulates insulin secretion and also affords pleiotropic effects including protective effects on blood vessels. Multiple factors regulate GLP-1 secretion after meals, but a group of apparently healthy subjects showed blunted responses of GLP-1 secretion in our previous study. In this study, we examined the possibility that the reduced capacity of GLP-1 secretion is associated with increased extent of coronary artery stenosis in non-diabetic patients.

Methods and results

Non-diabetic patients who were admitted for coronary angiography without a history of coronary interventions were enrolled. Coronary artery stenosis was quantified by Gensini score (GS), and GS ≥10 was used as an outcome variable based on results of earlier studies indicating its predictive value for cardiovascular events. The patients (mean age, 66.5±8.8 years; 71% males, n=173) underwent oral 75 g-glucose tolerant tests for determination of glucose, insulin and active GLP-1 levels. The area under the curve of plasma active GLP-1 (AUC-GLP-1) was determined as an index of GLP-1 secretion capacity. AUC-GLP-1 was not correlated with fasting glucose, AUC-glucose, serum lipids, indices of insulin sensitivity or estimated glomerular filtration rate. In multivariate logistic regression analysis for GS ≥10, AUC-GLP-1 &lt; median, age and hypertension were selected as explanatory variables, though fasting GLP-1 level was not selected.

Conclusion

The findings indicate significant association of reduced GLP-1 secretion capacity with increased extent of coronary artery stenosis in non-diabetic patients. A causal relationship between change in GLP-1 secretion capacity and coronary stenosis remains to be examined by a longitudinal study

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This study was supported in part by a research grant from Investigator-Initiated Studies Program of Merck Sharp & Dohme Corp./MSD K.K.

Chlorine dioxide is a more potent antiviral agent against SARS-CoV-2 than sodium hypochlorite

BACKGROUND

A new coronavirus (SARS-CoV-2) abruptly emerged in Wuhan, China, in 2019 and rapidly spread globally to cause the COVID-19 pandemic.

AIM

To examine the anti-SARS-CoV-2 activity of the potent disinfectant Cleverin, the major disinfecting component of which is chlorine dioxide (ClO₂); and to compare the results with that of sodium hypochlorite in the presence or absence of 0.5% or 1.0% foetal bovine serum (FBS).

METHODS

Concentrated SARS-CoV-2 viruses were treated with various concentrations of ClO₂ and sodium hypochlorite and 50% tissue culture infective dose was calcurated to evaluate the antiviral activity of each chemical.

FINDINGS

When SARS-CoV-2 viruses were treated with 0.8 ppm ClO₂ or sodium hypochlorite, viral titre was decreased only by 1 log₁₀ TCID₅₀/mL in 3 min. However, the viral titre was decreased by more than 4 log₁₀ TCID₅₀/mL when treated with 80 ppm of each chemical for 10 s regardless of presence or absence of FBS. It should be emphasized that treatment with 24 ppm of ClO₂ inactivated more than 99.99% SARS-CoV-2 within 10 s or 99.99% SARS-CoV-2 in 1 min in the presence of 0.5% or 1.0% FBS, respectively. By contrast, 24 ppm of sodium hypochlorite inactivated only 99% or 90% SARS-CoV-2 in 3 min under similar conditions. Notably, except for ClO₂, the other components of Cleverin such as sodium chlorite, decaglycerol monolaurate, and silicone showed no significant antiviral activity.

CONCLUSION

Altogether, the results strongly suggest that although ClO₂ and sodium hypochlorite are strong antiviral agents in absence of organic matter but in presence of organic matter, ClO₂ is a more potent antiviral agent against SARS-CoV-2 than sodium hypochlorite.

Validation and standardization of DNA extraction and library construction methods for metagenomics-based human fecal microbiome measurements

BACKGROUND

Validation and standardization of methodologies for microbial community measurements by high-throughput sequencing are needed to support human microbiome research and its industrialization. This study set out to establish standards-based solutions to improve the accuracy and reproducibility of metagenomics-based microbiome profiling of human fecal samples.

RESULTS

In the first phase, we performed a head-to-head comparison of a wide range of protocols for DNA extraction and sequencing library construction using defined mock communities, to identify performant protocols and pinpoint sources of inaccuracy in quantification. In the second phase, we validated performant protocols with respect to their variability of measurement results within a single laboratory (that is, intermediate precision) as well as interlaboratory transferability and reproducibility through an industry-based collaborative study. We further ascertained the performance of our recommended protocols in the context of a community-wide interlaboratory study (that is, the MOSAIC Standards Challenge). Finally, we defined performance metrics to provide best practice guidance for improving measurement consistency across methods and laboratories.

CONCLUSIONS

The validated protocols and methodological guidance for DNA extraction and library construction provided in this study expand current best practices for metagenomic analyses of human fecal microbiota. Uptake of our protocols and guidelines will improve the accuracy and comparability of metagenomics-based studies of the human microbiome, thereby facilitating development and commercialization of human microbiome-based products. Video Abstract.

Expressions of conventional vitellogenin and vitellogenin-like A in worker brains are associated with a nursing task in a ponerine ant

In eusocial insect colonies, non-reproductive workers often perform different tasks. Tasks of an individual worker are shifted depending on various factors, e.g., age and colony demography. Although a vitellogenin (Vg) gene play regulatory roles in both reproductive and non-reproductive division of labours in a honeybee, it has been shown that the insect Vg underwent multiple gene duplications and sub-functionalisation, especially in apical ant lineages. The regulatory roles of duplicated Vgs were suggested to change evolutionarily among ants, whereas such roles in phylogenetically basal ants remain unclear. Here, we examined the expression patterns of conventional Vg (CVg), Vg-like A, Vg-like B and Vg-like C, as well as Vg receptor, during the task shift in an age-dependent manner and under experimental manipulation of colony demography in a primitive ant Diacamma sp. Expressions of CVg and Vg-like A in a brain were associated with a nursing task. It is suggested that associations of brain expressions of these Vgs with worker tasks were acquired in the basal ant lineage, and that such Vg functions could have sub-functionalised in the derived ant lineage.

Clinical determinants and prognostic impact of osteoporosis in patients with chronic heart failure

Background

Despite accumulating evidence of a close association between orthopedic fractures and chronic heart failure (CHF), the clinical risk factors of osteoporosis, defined as reduction in bone mineral densities (BMDs), in CHF patients have not been systematically analyzed. In addition, the impact of osteoporosis on prognosis of CHF remains unclear.

Aims

We aimed to clarify the prevalence, clinical risk factors, and prognostic impact of osteoporosis in CHF patients.

Methods

We retrospectively examined 303 CHF patients (75 years, [interquartile range (IQR), 66–82 years]; 41% female). BMDs at the lumber spine, femoral neck, and total femur were measured by dual-energy X-ray absorptiometry (DEXA), and osteoporosis was diagnosed when BMD at any of the three sites was less than 70% of Young Adult Mean.

Results

The prevalence of osteoporosis in the CHF patients was 40%. Patients with osteoporosis were older (79 [IQR, 74–86] vs. 72 [IQR, 62–80] years), included a large percentage of females, had slower gait speed and had lower body mass index (BMI). Loop diuretics and warfarin were used more frequently and direct oral anticoagulants (DOACs) were used less frequently in patients with osteoporosis than in patients without osteoporosis. Multivariate logistic regression analysis indicated that sex (odds ratio [OR] 5.07, 95% Confidence Interval [CI] 2.68–9.61, p&lt;0.01), BMI (OR, 0.83; 95% CI, 0.75–0.91; p&lt;0.01), gait speed (OR, 0.80; 95% CI, 0.70–0.92; p&lt;0.01), loop diuretics use (OR, 2.52; 95% CI, 1.20–5.27; p=0.01) and no DOACs use (OR, 0.43; 95% CI, 0.19–0.96; p=0.04) were independently associated with osteoporosis. During the mean follow-up period of 290±254 days, 92 patients (30.4%) had adverse events. When patients with osteoporosis were divided into subgroups according to the number of sites with BMD of an osteoporosis level, Kaplan-Meier survival curves showed that the rate of adverse events (death and cardiovascular events) was higher in patients with osteoporotic BMD at two or more sites than in patients without osteoporosis (51% vs. 23%, p=0.03) (Figure). In multivariate Cox regression analyses, osteoporotic BMD at two or more sites was an independent predictor of adverse events after adjustment for age, sex, and NT-proBNP level (Hazard ratio, 1.74; 95% CI, 1.01–2.99; p=0.04).

Conclusion

The risk of osteoporosis may be increased in users of loop diuretics and may be decreased in users of DOACs in CHF patients. Extent of osteoporosis is a novel predictor of adverse events in CHF patients.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Japan Society for the Promotion of Science KAKENHI

Impact of frailty on super elderly patients with peripheral artery disease from the I-PAD 3 year registry

Background

Unlike age, frailty is often not taken into account in treatment indications of Endovascular treatment (EVT). One of the reason is that there was little known the relationship between frailty and the outcome of EVT for super elderly patients with peripheral artery disease (PAD). We investigate impacts of frailty on the super elderly patient prognosis who underwent EVT.

Purpose

To investigate impacts of frailty on the super elderly patient prognosis who underwent EVT.

Methods

From August 2015 to July 2016, 335 consecutive patients who underwent EVT were enrolled in the I-PAD registry from 7 institutes in Nagano prefecture. Among them, we selected and analyzed 91 super elderly PAD patients (≥80 years-old) and divided them into two groups:those with moderate or higher frailty (Clinical Frailty Scale (CFS) ≥6, n=28) and those without (CFS ≤5, n=63). The primary endpoints were cardiovascular death and major adverse cardiovascular and limb events (MACLE), defined as a composite of cardiovascular death, myocardial infarction, stroke, admission for heart failure, major amputation and revascularization.

Results

The median follow-up period was 2.7 years. Freedom rate from cardiovascular death and MACLE were significantly lower among patients with moderate or higher frailty than among those without (47.0% vs. 58.0%, P=0.03; 39.1% vs. 68.5%, P&lt;0.01).

Conclusion

The prognosis of super elderly patients with moderate or higher frailty is worse than those without.

Funding Acknowledgement

Type of funding source: None

Inhibition of xanthine oxidase ameliorates functional and metabolic impairment in type 2 diabetic hearts under pressure overload

Background

We recently reported that upregulated AMP deaminase (AMPD), via reduction in the tissue adenine nucleotide pool, contributes to exacerbation of diastolic dysfunction under pressure overload in OLETF, a rat model of obese type 2 diabetes (T2DM). Upregulated AMPD also possibly promotes xanthine oxidase (XO)-mediated ROS production, since AMPD deaminases AMP to IMP, which is further converted to inosine, providing substrates of XO, hypoxanthine and xanthine. Here, we examined the hypothesis that inhibition of XO ameliorates the pressure overload-induced diastolic dysfunction by suppression of ROS-mediated mitochondrial dysfunction and/or vascular dysfunction in T2DM rats.

Methods and results

Metabolomic analyses revealed that levels of xanthine and uric acid in the LV myocardium were significantly higher by 37% and 51%, respectively, in OLETF than in LETO, non-diabetic control rats, under the condition of phenylephrine-induced pressure overloading (200–230 mmHg). Myocardial XO activity in OLETF was 57.9% higher than that in LETO, which may be attributed to 31% higher level of inosine, a positive regulator of XO, in OLETF than in LETO. The activity of XO was significantly attenuated by administration of topiroxostat, an XO inhibitor at 0.5 mg/kg/day for 14 days. Pressure volume loop analyses showed that the pressure overloading resulted in significantly higher LVEDP in OLETF than in LETO (18.3±1.5 vs. 12.2±1.3 mmHg, p&lt;0.05, n=7), though LVEDPs at baseline were comparable in OLETF and LETO (5.6±0.4 vs. 4.7±0.7 mmHg). Treatment with topiroxostat significantly suppressed the pressure overload-induced elevation of LVEDP in OLETF (18.3±1.5 vs. 11.3±1.1 mmHg, p&lt;0.05) but not in LETO. Under the condition of pressure overloading, Ea/Ees, an index for ventricular-arterial coupling, was higher in OLETF than in LETO (2.3±0.3 vs. 1.6±0.3, p&lt;0.05), and it was also improved by topiroxostat in OLETF (1.2±0.2, p&lt;0.05). Myocardial ATP content was lower in OLETF than in LETO (2966±400 vs. 1818±171 nmol/g wet tissue, p&lt;0.05), and treatment with topiroxostat significantly restored the ATP level (2629±307 nmol/g wet tissue). The LV myocardium of OLETF under pressure overload showed significantly higher level of malondialdehyde and 4-hydroxynonenal, an indicator of lipid peroxidation, than that of LETO. Measurement of oxygen consumption rate by Seahorse XFe96 Analyzer in mitochondria isolated from LV tissues revealed that state 3 respiration was significantly suppressed in OLETF by 43% compared to LETO, and it was restored by treatment with topiroxostat.

Conclusion

Both activity and substrates of XO are increased in T2DM hearts, in which upregulation of AMPD may play a role. Inhibition of XO ameliorates pressure overload-induced diastolic dysfunction and improves ventricular-arterial coupling in diabetic hearts, most likely through protection of mitochondrial function from ROS-mediated injury.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Grant-in-aid for Scientific Research (#26461132, #17K09584) from the Japanese Society for the Promotion of Science

Reduced cytotoxicity in doxorubicin-exposed HepG2 cells pretreated with menthol due to upregulation of P-glycoprotein

The aim of the present study was to examine changes in the expression and activity of P-glycoprotein (P-gp) in human hepatocellular carcinoma HepG2 cells after exposure to menthol, and their relationship to the cytotoxicity of and apoptotic responses to doxorubicin (DOX), a substrate of P-gp, in the cells. The expression of P-gp in HepG2 cells was significantly increased by menthol treatment. Intracellular accumulation of DOX in HepG2 cells was significantly lower in the menthol-treated group than in the control group, but this phenomenon was abolished in the presence of verapamil. Decreased cell viability by DOX was significantly attenuated by 24-h menthol treatment prior to DOX exposure, which coincided with the changes in mRNA expression of Bcl-xl and caspase-3. These results demonstrate that menthol causes hepatocellular carcinoma cells to acquire resistance to DOX by increasing its efflux through the upregulation of P-gp.

P207 Synergetic effect of amino acid and ketone metabolism underlies empagliflozin-mediated cardioprotection in the type 2 diabetic heart

Funding Acknowledgements

Boehringer Ingelheim

Background

 Although emerging evidence has indicated that sodium glucose cotransporter 2 (SGLT2) inhibitors restore impaired cardiac energetics in type 2 diabetes mellitus (T2DM), the underlying molecular mechanisms have yet to be established.  Augmented utilization of ketone is one proposed hypothesis, but depletion of succinyl-CoA triggered by the conversion of ketone back to acetyl-CoA by SCOT (succinyl-CoA:3-oxoacid CoA transferase) may hamper oxidative capacity of the tricarboxylic acid (TCA) cycle, which also requires succinyl-CoA.  The recent finding that empagliflozin augments systemic amino acid metabolism in patients with T2DM led us to hypothesize that the anaplerotic effect of amino acid on the TCA cycle complements ketone oxidation.

Methods and Results

 Myocardial infarction (MI) was induced in T2DM rats (OLETF) and control rats (LETO).  Survival rate at 48 hours after MI was significantly lower in OLETF than in LETO (40% vs 84%), and empagliflozin treatment (10 mg/kg/day, 14 days) before MI improved the survival rate in OLETF to 70%.  Metabolome analysis was performed using heart tissues from the non-infarct region 12 hours after MI.  Using principal component analysis, data from 92 metabolites that were detected were compressed into 2 dimensions, and the first component (PC1) clearly separated empagliflozin-treated OLETF from non-treated LETO and OLETF.  Analysis of factor loading of each metabolite for PC1 revealed that branched chain amino acids leucine, isoleucine and valine, the latter two of which can be oxidized to succynyl-CoA, and β-hydroxybutyrate were the top four metabolites that characterized empagliflozin treatment.  Furthermore, in comparison to LETO, OLETF treated with empagliflozin showed 50% higher levels of glutamine and glutamate, both of which can replenish the TCA cycle at the level of α-ketoglutarate.  In OLETF, empagliflozin significantly increased the TCA cycle intermediates citrate, cis-aconitate and malate by 74%, 119% and 59%, respectively.  OLETF showed 86% higher lactate and 38% lower ATP than those in LETO, but levels of the metabolites were normalized by empagliflozin, suggesting improved glucose oxidation.

Conclusions

  The present analyses showed that amino acid and ketone metabolism are metabolic pathways that are most affected by empagliflozin.  Coordination of these "starvation-induced pathways" may underlie the favorable metabolic effect of empagliflozin in T2DM hearts.

41 Geometric change in valvular apparatus during tricuspid repair for severe tricuspid regurgitation

Background

For repairing severe tricuspid regurgitation (TR) with leaflet tethering, our team employs spiral suspension procedure, in which papillary muscles (PMs) are approximated and suspended towards annulus by suture in addition to annuloplasty.

Purpose

To visualize subtricuspid apparatus and investigate its geometric change by the procedure, comparing with annuloplasty alone.

Methods

11 patients who underwent spiral suspension and 10 patients who underwent annuloplasty alone were studied. Using 3D dataset derived from transesophgeal echocardiography with transgastric approach, the distances between the mid septal annulus (point C) and the anterior PM tip (point A) and posterior PM (point P) were calculated. Also, annular perimeter, leaflet surface area and tenting height were measured

Results

In all cases, PM tips could be visualized and identified for the measurements. By spiral suspension, the distance CA and tenting height were significantly reduced. On the other hand, by annuloplasty alone, CA and tenting height were likely to be increased but statistically not significant.

Conclusions

Spiral suspension ameliorated leaflet tethering with relocating PMs. Annuloplasty alone reduced leaflet surface area, which indicates increase of coaptation surface. Interestingly, PM tip- annulus distance and tenting height were possibly increased by annuloplasty. Further investigation is need in large number.

Result of measurements Annuloplasty alone Spiral suspension Pre-op Post-op Pre-op Post-op Annular perimeter, mm 120.9 ± 11.2 78.8 ± 5.1* 142.4 ± 18.2* 81.1 ± 6.4** Leaflet surface area, cm2 13.1 ± 3.1 5.6 ± 0.9* 19.3 ± 4.8* 5.8 ± 0.8** Tenting height, mm 2.8 ± 2.3 3.1 ± 1.2 7.0 ± 4.8* 2.9 ± 2.6** CA, mm 27.3 ± 3.9 29.1 ± 6.2 35.7 ± 6.9* 29.6 ± 5.2** CP, mm 33.1 ± 6.0 33.8 ± 9.4 38.5 ± 8.2 33.9 ± 6.1 *p &lt; 0.05, vs Annuloplasty alone pre-op **p &lt; 0.05, vs Spiral suspension pre-op

Abstract 41 Figure. Pre- and post-operative valve apparatus

P121 Pressure overload-induced functional and metabolic impairments in type 2 diabetic hearts are ameliorated by inhibition of xanthine oxidase

Funding Acknowledgements

SANWA KAGAKU KENKYUSHO Co., Ltd.

Background

  We have recently demonstrated that AMP deaminase (AMPD) is upregulated in OLETF, obese type 2 diabetic (T2DM) rats, and that the upregulated AMPD contributes to depletion of myocardial ATP at the time of pressure overload, leading to diastolic dysfunction.  On the other hand, AMPD promotes the formation of IMP from AMP, and IMP is in turn further converted to hypoxanthine and xanthine, substrates of xanthine oxidase (XO), which produces uric acid with ROS as a byproduct.  Based on these findings, we tested the hypothesis that inhibition of XO ameliorates the pressure overload-induced diastolic dysfunction in T2DM rats. 

Methods and results

Metabolomic analyses of the left ventricular myocardium revealed that levels of myocardial hypoxanthine and xanthine were significantly higher by 30% and 28%, respectively, in OLETF than in LETO, non-diabetic control rats, under the condition of pressure overloading (200-230 mmHg) induced by phenylephrine infusion. Myocardial XO activity in OLETF was 57.9% higher than that in LETO, and the activity was significantly attenuated by oral administration of topiroxostat, an XO inhibitor, at 0.1-0.5 mg/kg/day for 14 days in a dose-dependent manner.  Pressure volume loop analyses showed that the pressure overloading induced by phenylephrine infusion resulted in significantly higher LVEDP in OLETF than in LETO (18.3 ± 1.5 vs. 12.2 ± 1.3 mmHg, p &lt; 0.05, n = 7), though LVEDPs at baseline were comparable in OLETF and LETO (5.6 ± 0.4 vs. 4.7 ± 0.7 mmHg).  Treatment with topiroxostat significantly suppressed the pressure overload-induced elevation of LVEDP in OLETF (18.3 ± 1.5 vs. 11.3 ± 1.1 mmHg, p &lt; 0.05) but not in LETO.  Tau, the time constant of LV pressure decay, was significantly prolonged to 14.7 ± 0.7 ms (p &lt; 0.05) by pressure overloading in OLETF but not in LETO, though baseline Tau values were similar in LETO and OLETF (6.1 ± 0.2 vs. 8.0 ± 0.4 ms).  The prolongation of Tau by pressure overloading in OLETF was significantly attenuated by treatment with topiroxostat.  Ea/Ees, an index for ventricular-arterial coupling, was higher in OLETF than in LETO (2.3 ± 0.3 vs. 1.6 ± 0.3, p &lt; 0.05) under the condition of pressure overloading, and it was also improved by topiroxostat in OLETF (1.2 ± 0.2, p &lt; 0.05).  Myocardial ATP content was lower in OLETF than in LETO under the condition of pressure overloading (2966 ± 400 vs. 1818 ± 171 nmol/g wet tissue, p &lt; 0.05), but treatment with topiroxostat significantly restored the ATP level (2629 ± 307 nmo/g wet tissue). Conclusion:  In T2DM hearts, not only XO activity but also XO substrates are upregulated and upregulated AMPD may be involved in the upregulation.  Inhibition of XO ameliorates pressure overload-induced diastolic dysfunction and improves ventricular-arterial coupling most likely through augmented ATP preservation.

CAPABILITIES OF THE ARADOS-WG03 REGIONAL NETWORK FOR LARGE-SCALE RADIOLOGICAL AND NUCLEAR EMERGENCY SITUATIONS IN ASIA

In 2015, the Asian Radiation Dosimetry Group established a regional network of biological dosimetry laboratories known as the ARADOS-WG03 (Working Group 03; Biological Dosimetry). A survey was conducted in 2017 to evaluate the capabilities and capacities of the participating laboratories for emergency preparedness and responses in large-scale nuclear and/or radiological incidents. The results of this survey were identified and assessed. The data provide important information on the current state of emergency cytogenetic biological dosimetry capabilities in the Asian region.

Ecological impact assessment of a bioaugmentation site on remediation of chlorinated ethylenes by multi-omics analysis

Bioremediation may affect the ecological system around bioremediation sites. However, little is known about how microbial community structures change over time after the initial injection of degraders. In this study, we have assessed the ecological impact of bioaugmentation using metagenomic and metatranscriptomic approaches to remove trichlorinated ethylene/cis-dichloroethylene (TCE/cDCE) by Rhodococcus jostii strain RHA1 as an aerobic chemical compound degrader. Metagenomic analysis showed that the number of organisms belonging to the genus Rhodococcus, including strain RHA1, increased from 0.1% to 76.6% of the total microbial community on day 0 at the injection site. Subsequently, the populations of strain RHA1 and other TCE/cDCE-degrading bacteria gradually decreased over time, whereas the populations of the anaerobic dechlorinators Geobacter and Dehalococcoides increased at later stages. Metatranscriptomic analysis revealed a high expression of aromatic compound-degrading genes (bphA1-A4) in strain RHA1 after RHA1 injection. From these results, we concluded that the key dechlorinators of TCE/cDCE were mainly aerobic bacteria, such as RHA1, until day 1, after which the key dechlorinators changed to anaerobic bacteria, such as Geobacter and Dehalococcocides, after day 6 at the injection well. Based on the α-diversity, the richness levels of the microbial community were increased after injection of strain RHA1, and the microbial community composition had not been restored to that of the original composition during the 19 days after treatment. These results provide insights into the assessment of the ecological impact and bioaugmentation process of RHA1 at bioremediation sites.

P943The impact of diabetes on patients with frail after endovascular treatments: from I-PAD registry

Background

Diabetes mellitus (DM) is known to be one of the risks of arteriosclerosis. However, it is still unknown whether DM is a risk factor also in secondary prevention of frail patients after endovascular treatments (EVT)

Purpose

To investigate impact of diabetes on patients with frail after EVT.

Methods

From July 2015 to July 2016, 371 consecutive PAD patients who performed EVT were enrolled in I-PAD registry. We could conduct follow up survey 361 patients (446 lesions) and divided into 2 groups; with diabetes (185 patients, 226 lesions) or without diabetes (176 patients, 220 lesions) and analyzed. And among them,we selected 96 patients with frail and divided into 2 groups; with diabetes (49 patients, 70 lesions) or without diabetes (46 patients, 58 lesions) and analyzed. We defined frail patients as the patients with Clinical Frailty Scale 5 (mild frail) or higher. The primary end point was all-cause-death and major adverse limb events (MALE: TLR, TVR, major amputations) at 1 year.

Result

At 1 years in the patients group with diabetes, overall survival and freedom from MALE were significantly lower (81.7% vs 95.8% P<0.0001; 80.0% vs 94.6%, P<0.0001) than the group without diabetes.Among the patients with frail, between the patients group with diabetes and the group without, there is no significant differences in overall survival and freedom from MALE (88.2% vs 88.9% P=0.83; 80.7% vs 84.1%, P=0.55) at 5 years.

Conclusion

The prognosis of patients with diabetes after EVT was worse than the patient without. On the other hand, the prognosis of frail patients with diabetes after EVT was no difference with the frail patient without diabetes in this study.

P942Impact of left ventricular ejection fraction in patients with critical limb ischemia: from I-PAD registry

Introduction

In patients with critical limb ischemia (CLI) it is known that malnutrition, low BMI, inflammation and so on are prognostic factors. But, it is unclear whether left ventricular ejection fraction (LVEF) affects prognosis of CLI patients. So we investigated that LVEF affects prognosis of CLI patients.

Methods

From July 2015 to July 2016, 371 consecutive peripheral artery disease patients who performed endovascular treatment (EVT) were enrolled in I-PAD registry. 179 of them were patients with CLI. We could conduct follow up survey about 126 (age 75.5±11.1, men 63.5%) and divided two groups according to their LVEF (group with LVEF≤40%, n=13, group without LVEF≤40%, n=113). The primary end point was major adverse limb events (MALE: TLR, TVR, major amputations) and secondary end point was all-cause death.

Results

The median follow-up period was 11.5±6.7 months. The 18 months MALE rate was significant higher in the group with low LVEF than group without low LVEF (76.9% vs 37.2% p<0.05). The 18months all-cause death tended to be higher in the group with low LVEF, however there was not statistical significance in the two groups (53.8% vs 24.8% p=0.09).

Conclusion

LVEF was associated with MALE in patients with CLI.

P6402Ischemic and bleeding events during dual antiplatelet therapy after second-generation drug-eluting stent implantation in hemodialysis patients: a propensity score-matched analysis

Background

Dual-antiplatelet therapy (DAPT) after second-generation drug eluting stent (2-DES) implantation reduced the risk of stent thrombosis and subsequent ischemic events, with an increase in bleeding risk. Although chronic kidney disease patients have high ischemic and bleeding risk, little is known about both risks in hemodialysis patients after 2-DES implantation during DAPT.

Method

From July 2009 to March 2017, we retrospectively analyzed post-discharge major adverse cardiac and cerebrovascular events [MACCE: cardiac death, myocardial infarction, target vessel revascularization (TVR) and cerebral infarction] and bleeding events in 644 consecutive patients during DAPT after 2-DES implantation. We divided them into 2 groups [102 hemodialysis (HD) and 518 non-hemodialysis (Non-HD) patients, mean age, 71±10 years] after excluding 24 patients (lost to follow up and peritoneal dialysis). Follow-up period was 49±24 months. Median DAPT duration was 12 months. The primary endpoint was MACCE. The secondary endpoint was bleeding events according to the Bleeding Academic Research Consortium (BARC) type 2, 3, or 5. MACCE and bleeding events were compared between HD and Non-HD by using the propensity score-matching (PSM) method.

Results

Among the 620 eligible patients, the primary and secondary events occurred in 207 (33.3%) and 76 (12.3%) patients, respectively. The rates of unadjusted MACCE [HD vs Non-HD: 53.9% vs 29.3%; Hazard ratio (HR) 2.39, p<0.01] and bleeding events (HD vs Non-HD: 21.6% vs 10.4%; HR 2.50, p<0.01) were significantly higher in HD than Non-HD.

After 1-to-1 propensity score adjustment for baseline differences (hypertension, diabetes mellitus, low ejection fraction, low albumin, anemia, and high C-reactive protein), a total of 160 patients (80 HD vs 80 Non-HD) was created. The rate of MACCE [HD vs Non-HD: 52.5% vs 31.3%; adjusted HR 2.04, p<0.01] was significantly higher in HD than Non-HD. Regarding MACCE, cardiac death (HD vs Non-HD: 18.8% vs 8.8%; adjusted HR 2.65, p=0.03) and TVR (HD vs Non-HD: 15.0% vs 6.3%; adjusted HR 2.74, p=0.046) occurred significantly higher in HD. On the other hand, bleeding events did not exhibit significant differences though HD had a numerically higher event rate (HD vs Non-HD: 25.0% vs 16.3%; adjusted HR 1.68, p=0.15), indicating that the bleeding risk in HD would be strongly dependent on the patient's background.

Conclusions

As a result of PSM, HD was shown to contribute to ischemic risk rather than bleeding risk. Even in the 2-DES era, HD was an independent risk factor of cardiac death and TVR. Therefore, further study on the current regimen of DAPT would be necessary while balancing both ischemic and bleeding risk.

P1957Impact of fraility on the super elderly patients with peripheral artery disease

Background

The current consensus is that frail patients have high risks of mortality. However, it remains unclear whether frailty is associated with mortality risks in super-elderly patients with peripheral artery disease (PAD).

Methods

The I-PAD registry was a prospective multicenter observational study involving 12 institutions in Nagano prefecture in Japan. From July 2015 to July 2016, the I-PAD registry enrolled 371 consecutive PAD patients who had undergone endovascular therapy (EVT). Among them, we selected and analysed 109 PAD patients who were >80 years old when they had undergone EVT and divided them into two groups: those with frailty (Clinical Frailty Scale≥5, n=47) and those without frailty (Clinical Frailty Scale≤4, n=62). The primary endpoints were overall survival and major adverse limb events (MALE), defined as a composite of all-cause death, major amputation and revascularization.

Results

The median follow-up period was 1.58±0.3 years. Overall, 109 patients with a mean age of 84.8±4.0 years, of whom 63.3% were men, were included. Overall survival and freedom from MALE were significantly lower among patients with frailty than among those without frailty (60.5% vs. 91.6%, P<0.001; 51.4% vs. 87.5%, P<0.001; respectively).

Conclusion

The prognosis of super-elderly patients with frailty is worse than that of patients without frailty.

P936Impact of left ventricular ejection fraction in patients with peripheral artery disease: from I-PAD registry

Introduction

In patients with peripheral artery disease (PAD) it is known that CVD is one of prognostic factors. But, it is unclear whether left ventricular ejection fraction (LVEF) affects prognosis of PAD patients. So we investigated that LVEF affects prognosis of PAD patients.

Methods

From July 2015 to July 2016, 371 consecutive PAD patients who performed endovascular treatment (EVT) were enrolled in I-PAD registry. We could conduct follow up survey about 337 (age 73.8±9.6, men 72.4%) patients and divided two groups according to their LVEF (group with LVEF≤40%, n=18, group without LVEF≤40%, n=319). The primary end point was major adverse limb events (MALE: TLR, TVR, major amputations) and secondary end point was all-cause death.

Results

The median follow-up period was 13.6±5.7 months. The 18 months MALE and all-cause death rate were significantly higher in the group with low LVEF than group without low LVEF (61.1% vs 21.6% p<0.001, 44.4% vs 11.6% p<0.001).

Conclusion

LVEF was significantly associated with MALE and all-cause death in patients with PAD.

P4537Impact of body composition analysis on prediction of short-term readmission events in heart failure: muscle wasting vs. obesity

Background

Obesity, defined as higher body mass index (BMI), is associated with better prognosis in patients with chronic heart failure (CHF), though the presence of obesity is a risk factor of development of CHF (Obesity paradox). On the other hand, muscle wasting, i.e. reduction in skeletal muscle mass, is frequently observed in CHF, leading to lower exercise capacity and poor cardiovascular outcome.

Purpose

The aim of this study was to examine whether analysis of body composition improves prediction of short-term readmission rates in patients with CHF.

Methods

We retrospectively analyzed data for 167 consecutive HF patients who were admitted to our institute for management of HF and received a Dual-energy X-ray absorptiometry (DEXA) scan. Muscle wasting was defined as DEXA-measured appendicular skeletal muscle mass index <7.0 kg/m2 in male and <5.4 kg/m2 in female according to the Asian Working Group for Sarcopenia criteria. Obesity was defined according to the criteria by the use of DEXA-measured percent body fat mass: >25% in male, >30% in female. The primary endpoint was readmission due to cardiac events including worsening heart failure, arrhythmia, and cardiopulmonary arrest during a 180-days follow-up period after discharge.

Results

The mean age of the patients was 74±13 years and 46% of them were male. The mean BMI was 21.8±3.8 kg/m2. Forty-seven percent of the patients were classified as NYHA functional class III. The most frequent etiology of HF was cardiomyopathy (30%), followed by ischemic heart disease (27%) and valvular heart disease (27%). The prevalence of muscle wasting and that of obesity were 69% and 59%, respectively. Patients with muscle wasting had lower BMI level, higher prevalence of NYHA functional class III and diabetes mellitus compared with those without muscle wasting. On the other hand, patients with obesity had higher prevalence of hypertension and dyslipidemia, higher level of BMI, fasting plasma insulin and triglyceride, and lower level of HDL-cholesterol compared with those without obesity. During the follow-up period, 34 patients (19%) were re-hospitalized due to cardiac events. Kaplan-Meier survival curves showed that patients with obesity had a significantly lower readmission rate during a 180-days follow-up period than did the patients without obesity (14.3% vs. 29.0%, Log-Rank test, p<0.01). There was no difference in readmission rates between patients with and without muscle wasting (20.0% vs. 21.2%, p=0.88). In multivariate Cox regression analyses adjusted for age, sex, diabetes, and renal function, obesity was independently associated with lower readmission rates (hazard ratio 0.45, 95% confidence interval 0.22–0.93). However, the association between obesity and readmission rate was lost after the adjustment for NT-proBNP levels.

Conclusion

Body composition analysis by DEXA enables to find CHF patients with increased fat mass who have lower risk of short-term readmission.

P2696Clinical characteristics of late catch-up phenomenon after implantation of 2nd generation drug eluting stent

Introduction

Late catch-up phenomenon (LCU) of 1st generation drug eluting stent (DES) has been increasing yearly despite the rate of restenosis in 1 year has reduced compared with bare metal stent (BMS). 2nd generation DES was more improved than 1st generation DES and suggested more benefits about clinical outcome.

Purpose

To investigate the incidence and predictor of LCU after implantation of 2nd generation DES and to evaluate the association between LCU phenomenon and adverse events.

Methods

Between August 2012 and July 2013, a total of 1665 consecutive patients (1956 lesions with elective/urgent PCI) were enrolled in SHINANO 5 years Registry (a prospective observational multicenter cohort study) from 13 institutions in Nagano, Japan. 711 patients that were treated with 2nd generation DES and 576 patients with BMS were selected. Exclusion criterias were cases of 1st DES, only POBA, only aspiration and chronic total occulusion.

Results

There were significant difference about patients background between BMS and 2nd generation DES groups. Those groups were matched with propensity score. After matching, 822 patients (BMS group 411 patients, 2nd generation group 411 patients) were analyzed. The rates of 2nd DES and BMS restenosis 5 years after initial PCI were 9.2% and 8.5% (p=0.572), those of LCU were 2.6% and 5.6% (p=0.043) by 1 year landmark analysis. Cox proportional hazards analysis revealed that the DES in-stent restenosis (ISR) lesion and higher HbA1c were independent predictors for LCU from 1year to 5year (HR 5.304, p=0.009, HR 1.254, p=0.015), but 2nd generation DES was not. Kaplan Meier curve showed no association between LCU phenomenon and all cause death (p=0.446). Cox regression analysis showed LCU was not independent predictor for all cause death (p=0.414).

Conclusions

Implantation to DES-ISR lesion with 2nd generation DES was associated with higher LCU. Despite of more complex lesions with 2nd generation DES, there were no differences of LCU incidence between 2nd generation DES and BMS.

Acknowledgement/Funding

None

P1538Low energy intake predicts readmission of elderly heart failure patients independently of nutritional status

Background

Malnutrition is frequently present and closely associated with poor clinical outcomes in elderly heart failure (HF) patients. Our previous study showed that low energy intake (EI) is associated with worse functional status in elderly HF inpatients after cardiac rehabilitation, but significance of EI in prediction of hospital readmission has not been elucidated fully.

Purpose

We examined whether low EI is a predictor of readmission for cardiac events in elderly HF patients.

Methods

We retrospectively retrieved data for 298 HF patients aged ≥65 years (median age of 77 years, interquartile range [IQR]: 71 - 82, female: 53%) who admitted to our institute for diagnosis and treatment of HF. Medical records were reviewed with regard to demography, medical history, comorbidities, medications, laboratory data, echocardiograms, functional status, nutritional status and total energy intake. Nutritional status was assessed using the Mini Nutritional Assessment Short Form (MNA-SF) and total EI per day were calculated at discharge by a registered dietitian and a trained physical therapist. The primary endpoint was readmission due to cardiovascular events including worsening HF, arrhythmia, angina pectoris and myocardial infarction during a 1-year follow-up period.

Results

The median period of follow-up was 235 days (IQR: 78–365 days). The 1-year readmission rate for cardiovascular events was 54.4%. The cutoff values of MNA-SF score and EI, calculated by ROC curve analysis to predict the primary endpoint, were 7 points (area under the curve [AUC]: 0.59, sensitivity: 0.65, specificity: 0.50) and 31.8 kcal/kg/day (AUC: 0.59, sensitivity: 0.83, specificity: 0.35), respectively. Patients with low MNF-SF score (≤7) or low EI (≤31.8 kcal/kg/day) had significantly higher readmission rate during a 1-year follow-up period than did the patients with high MNF-SF score or EI (MNA-SF: 60.7% vs. 45.6%, p<0.01, EI: 60.4% vs. 36.8%, p<0.01), respectively. When patients were classified into four groups using cutoff values of MNA-SF score and EI, 1-year readmission rate was significantly higher in patients with low EI than in those with high EI regardless of MNF-SF scores. In multivariate Cox proportional hazard analyses adjusted for known prognostic factors in addition to age and gender, hazard ratios (HR) were significantly higher in patients with high MNA-SF score and low EI (adjusted HR: 2.81, 95% confidential interval [CI]: 1.15 - 9.32, p=0.02) and low MNA-SF score (≤7) and low EI (adjusted HR: 4.16, 95% CI: 1.72 - 13.72, p<0.01) than those with high MNA-SF score and high EI.

Kaplan-Meier curves of readmission rates

Conclusions

Low energy intake is a nutritional status-independent predictor of 1-year readmission rate in elderly HF patients.

P3590Impact of right ventricular branch slow flow phenomenon post percutaneous coronary intervention for acute coronary syndrome to predict sustained right ventricular dysfunction

Background

Although Right Ventricular dysfunction (RVD) is one of the predictor of poor prognosis, it is believed that ischemic RVD after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) restores quickly. Because right ventricular perfusion has more ischemic preconditioning compared with left ventricle, due to their complex perfusion system. However, little is known about the time courses of RVD after ACS-PCI andtheir prognosis. We evaluated the relationship between right ventricular branch slow flow phenomenon (RVB-SF) post ACS-PCI in right coronary artery (RCA) and RVD at 6–8 months follow-up.

Method

We retrospectively analyzed consecutive 82 patients who underwent PCI for ACS in proximal or mid portion of RCA from August 2011 to March 2018 in our institution. Finally, both baseline and follow-up data were obtained from 70 patients. We analyzed TIMI frame count (TFC) to confirm the presence of RVB-SF (TFC ≥40 frame) after PCI. We also analyzed right ventricular fractional area change (RVFAC) at baseline and follow-up using echocardiography to detect sustained RVD (RVFAC ≤35%).

Result

We divided the patients into two groups (RVB-SF: 36 patients, RVB non-SF: 34 patients). Patient clinical characteristics were similar in both groups (sex, age, risk factors, medication, onset to balloon time, left ventricular stroke volume, max creatine kinase). Baseline RVFAC and follow-up RVFAC was significantly smaller in RVB-SF than in RVB non-SF, respectively. (27.1±1.7% vs. 38.3±1.8%, 31.4±1.0% vs. 48.7±1.1%, P<0.0001). However, ΔRVFAC (follow-up RVFAC – baseline RVFAC) was similar between groups. The size of inferior vena cava and systolic pulmonary artery pressure at follow-up were similar in both groups (12.1±0.6 mm vs. 11.7±0.7 mm, P=0.67, 25.7±1.5 mmHg vs. 25.2±1.5 mmHg, P=0.82). In RVB non-SF, 10 patients (29.4%) were diagnosed clinical RVAMI. However, follow-up RVFAC were similar and preserved in both groups (RVAMI: 48.1±1.3%, non-RVAMI: 49.9±1.9%, P=0.85). In RVB-SF, 19 patients (52.7%) were diagnosed clinical RVAMI. Follow-up RVFAC did not improved significantly in both groups (RVAMI: 30.4±1.4% vs. non-RVAMI: 32.6±1.5%, P=0.70). Multivariate analysis showed RVB-SF was the only independent predictor of sustained RVD at 6–8 months follow-up after ACS-PCI.

Conclusion

RVB-SF findings after ACS-PCI for RCA could predict sustained RVD at mid-term follow-up, which may indicate future prolonged RVD.

P6453Activation of necroptotic pathway by downregulated caspase-8 expression is associated with progression of left ventricular remodeling in nonischemic dilated cardiomyopathy

Background

Necroptosis, a form of programmed necrosis, has been suggested to be involved in the pathogenesis of various pathological conditions including heart failure. Protein expression of caspase-8, an endogenous inhibitor of necroptosis, is reported to be downregulated in human failing hearts, but its clinical significance remains unclear.

Methods

Endomyocardial biopsy specimens were obtained from patients with nonischemic dilated cardiomyopathy (n=57, 56.2±14.5 years old, 70% male). The area stained with antibodies against caspase-8 and phospho-MLKL-Ser358 was calculated using an image analyzer, and fibrotic and cardiomyocyte areas were determined by Masson's Trichrome staining. Using a level of median caspase-8 expression (6.04% of the area of the myocardium with caspase-8 signal), patients were classified into a high caspase-8 expression group (H-cas8) and a low caspase-8 expression group (L-cas8).

Results

Caspase-8 signals were detected in cytoplasm and intercalated disks of cardiomyocytes. Patients in the L-cas8 group was younger (51.3±13.1 vs. 61.2±14.3 years old) and had larger left ventricular end-diastolic volume (LVEDV: 174±49 vs. 131±41 ml), larger left ventricular end-systolic volume (LVESV: 123±51 vs. 87±39 ml), and higher ratio of mitral peak velocity of early filling to late diastolic filling (E/A: 1.94±1.48 vs. 1.12±0.66) compared with the H-cas8 group. Caspase-8 expression level was positively correlated with age (r=0.34, p=0.01) and negatively correlated with LVEDV (r=−0.47, p<0.01), LVESV (r=−0.40, p<0.01), and E/A (r=−0.39, p<0.01) in simple linear regression analysis. The extent of myocardial fibrosis was not correlated with caspase-8 expression level. Multiple regression analysis indicated that LVEDV, LVESV, and E/A were independent explanatory factors of caspase-8 expression level after adjusting age and sex. Phospho-MLKL signals, an index of activation of necroptotic pathway, were frequently observed in cytoplasm, intercalated disks, and nuclei in the L-cas8 group but not in the H-cas8 group.

Conclusion

Lower caspase-8 expression in cardiomyocytes was associated with increased phosphorylation of MLKL and larger left ventricular volume, suggesting that downregulated caspase-8 may contribute to progression of myocardial remodeling via activation of MLKL in human dilated cardiomyopathy.

P6273Inhibitory phosphorylation of RIP1 at Ser320 induces nuclear translocation of TFEB, leading to suppression of necroptosis in cardiomyocytes

Background

Necroptosis, a form of programmed necrosis, has been shown to contribute to the pathogenesis of various diseases including ischemia/reperfusion injury and heart failure. We recently reported that necroptotic signals suppresses autophagy in cardiomyocytes and that rapamycin, an mTORC1 inhibitor, not only promotes autophagy but also protect the cells from necroptosis.

Purpose

We examined the mechanism by which rapamycin suppresses necroptosis of cardiomyocytes, focusing on regulation of RIP1 activity and autophagic flux.

Methods and results

In H9c2 cardiomyoblasts, necroptosis was induced by treatment with TNF and z-VAD-fmk (zVAD) for 24 h, and cell death was determined by LDH release (as % of total). The treatment with TNF/zVAD increased LDH release from 3.4±1.3% to 46.1±2.3%, and LDH release was suppressed by necrostatin-1 (5.9±0.9%), a RIP1 inhibitor, and by rapamycin (23.5±1.4%). The protective effect of rapamycin was mimicked by Ku-0063794, an mTORC1/2 inhibitor. TNF/zVAD induced RIP1-RIP3 complex formation, together with suppression of TNF-induced RIP1 cleavage, which was mitigated by rapamycin. In addition, rapamycin not only suppressed TNF/zVAD-induced phosphorylation of RIP1-Ser166, an index of RIP1 activation, but also increased phosphorylation of RIP1-Ser320, an inhibitory phosphorylation site. In cells transfected with RIP1-S320A, which lack Ser320 for inhibitory phosphorylation, rapamycin failed to suppress TNF/zVAD-induced RIP1-RIP3 binding and cell death. Immunoblot analyses showed that TNF/zVAD significantly increased level of LC3-II. The accumulation of LC3-II protein was not further increased by bafilomycin A1 (100 nM), an inhibitor of lysosomal protein degradation, indicating that accumulation of LC3-II by TNF/zVAD reflected suppression of autophagic flux. Inhibition of RIP1 by necrostatin-1 attenuated TNF/zVAD-induced accumulation of LC3 II. The restoration of autophagic flux in TNF/zVAD-treated cells by necrostatin-1 was confirmed by monitoring tandem RFP-GFP-LC3 transfected cells; necrostatin-1 increased a ratio of RFP-LC3-puncta (autolysosomes) to RFP-GFP-LC3-puncta (autophagosomes) in TNF/zVAD-treated cells. In addition, necrostatin-1 and rapamycin induced nuclear translocation of TFEB, a regulator of lysosome biogenesis, which was associated with upregulation of MCOLN1 mRNA, a downstream target of TFEB. Restoration of autophagic flux in TNF/zVAD-treated cells by necrostatin-1 was inhibited by siRNA-mediated knockdown of TFEB.

Conclusion

Activation of TFEB by inhibitiory phosphorylation of RIP1-Ser320 is a primary mechanism of cytoprotection afforded by mTORC1 inhibition against necroptosis.

COMPARISON OF BACTERIAL FLORA IN RIVER SEDIMENTS FROM FUKUSHIMA AND AOMORI PREFECTURES BY 16S RDNA SEQUENCE ANALYSIS

Monitoring of radioactive materials has been reported in rivers and soil in Fukushima post the Fukushima Daiichi Nuclear Power Plant accident in March 2011. However, there are few reports on the influence of this event on bacteria in forest soils and rivers. Therefore, through amplicon sequencing of 16S rDNA we compared the bacterial flora in river sediment soils from Fukushima prefecture and from an area not exposed to radioactive contamination, Aomori prefecture. The bacterial composition in the Aomori prefecture soil and Fukushima soil were found to be very similar at the phylum level. However, Fukushima soil had significantly fewer Bacteroidetes than the Aomori soil (p = 0.014), while the content of Firmicutes and Latescibacteria (WS3) was significantly higher (p = 0.001, 0.013 respectively). However, no increase in the content of radioactive-resistant bacteria was observed. In future studies, it is necessary to standardise the conditions for soil collection to assess its content of radioactive substances.