Gelatin nanofiber mats with Lipofectamine/plasmid DNA complexes for in vitro genome editing

Gelatin electrospun nanofiber mats are gaining interest for applications in biomaterials science, such as tissue engineering and drug/gene delivery systems. In this study, we report the use of electrospun gelatin nanofiber mats for plasmid DNA (pDNA) delivery. Gelatin nanofiber mats were insolubilized via cross-linking with glutaraldehyde. On the cross-linked mats, human embryonic kidney-derived HEK293 cells demonstrated high viability for 7 days of culture (>95%) and were able to proliferate during that time. The Lipofectamine/pDNA complexes were immobilized on the mats through immersion in a solution, and HEK293 cells cultured on these mats expressed GFP for 7 days. Furthermore, HEK293 cells did not express GFP via the pDNA complexes released from the mats because the ability to deliver pDNA into the cells was lost. Since the mats could be used to transfect multiple types of pDNA into the cells simultaneously, we have achieved targeted genome editing using the mats. These data highlight the potential of gelatin nanofiber mats with Lipofectamine/pDNA complexes for local gene therapy via pDNA delivery as well as genome editing.

Iron deficiency aggravates DMNQ-induced cytotoxicity via redox cycling in kidney-derived cells

Iron, an essential element for most of living organisms, participates in many biological functions. Since iron is redox-active transition metal, it is known that excessive levels stimulate the formation of reactive oxygen species (ROS) and exacerbate cytotoxicity. An iron deficiency is the most common nutritional deficiency disorder in the world (about 30% of the population) and is more common than cases of iron overload. However, the effects of iron deficiency on ROS-induced cytotoxicity and the maintenance of intracellular redox homeostasis are not fully understood. The present study reports on an evaluation of the effects of iron deficiency on cytotoxicity induced by several ROS generators. In contrast to hydrogen peroxide and erastin, the cytotoxicity of 2,3-dimethoxy-1,4-naphthoquinone (DMNQ), a redox cycling agent that induces intracellular superoxide anion formation, was exacerbated by iron deficiency. Cytochrome b₅ reductase was identified as a candidate enzyme responsible for the redox cycling of DMNQ under conditions of iron depletion. Moreover, the DMNQ-induced intracellular accumulation of ROS and a decrease in NADH/NAD⁺ ratios were enhanced by an iron deficiency. These negative changes were found to be ameliorated by overexpressing NAD(P)H:quinone oxidoreductase 1 (NQO1) in kidney-derived cells that originally showed a very low expression of NQO1. These results indicate that NQO1 plays a protective role against redox cycling quinone-mediated cytotoxicity under iron-depleted conditions. This is because NQO1 generates less-toxic hydroquinones via the two-electron reduction of quinones. The collective findings reported herein demonstrate that not only an iron overload but also an iron deficiency exacerbates ROS-mediated cytotoxicity.

Wiskott-Aldrich syndrome protein forms nuclear condensates and regulates alternative splicing

The diverse functions of WASP, the deficiency of which causes Wiskott-Aldrich syndrome (WAS), remain poorly defined. We generated three isogenic WAS models using patient induced pluripotent stem cells and genome editing. These models recapitulated WAS phenotypes and revealed that WASP deficiency causes an upregulation of numerous RNA splicing factors and widespread altered splicing. Loss of WASP binding to splicing factor gene promoters frequently leads to aberrant epigenetic activation. WASP interacts with dozens of nuclear speckle constituents and constrains SRSF2 mobility. Using an optogenetic system, we showed that WASP forms phase-separated condensates that encompasses SRSF2, nascent RNA and active Pol II. The role of WASP in gene body condensates is corroborated by ChIPseq and RIPseq. Together our data reveal that WASP is a nexus regulator of RNA splicing that controls the transcription of splicing factors epigenetically and the dynamics of the splicing machinery through liquid-liquid phase separation.

Establishment of mouse model of inherited PIGO deficiency and therapeutic potential of AAV-based gene therapy

Inherited glycosylphosphatidylinositol (GPI) deficiency (IGD) is caused by mutations in GPI biosynthesis genes. The mechanisms of its systemic, especially neurological, symptoms are not clarified and fundamental therapy has not been established. Here, we report establishment of mouse models of IGD caused by PIGO mutations as well as development of effective gene therapy. As the clinical manifestations of IGD are systemic and lifelong lasting, we treated the mice with adeno-associated virus for homology-independent knock-in as well as extra-chromosomal expression of Pigo cDNA. Significant amelioration of neuronal phenotypes and growth defect was achieved, opening a new avenue for curing IGDs.

AB0545 THYMUS VARIANTS ON IMAGING IN PATIENTS WITH PRIMARY SJÖGREN’S SYNDROME AND POLYMYOSITIS/DERMATOMYOSITIS PATIENTS

Background

The thymus, a primary lymphoid organ, plays a crucial role in immune system homeostasis [1,2]. Although several studies of an association between radiographic thymus variants and serological features in systemic autoimmune diseases such as systemic scleroderma, have been reported [3-6], information in patients with other systemic autoimmune disease, especially in primary Sjögren’s syndrome (pSS) or polymyositis/dermatomyositis (PM/DM) patients, is quite limited.

Objectives

We investigated the association between radiographic thymus variants and clinical and immunological features in patients with pSS and PM/DM, and clarified its significance.

Methods

Patients with pSS and PM/DM were randomly selected from all patients who had visited our department and underwent chest CT scan between April 2009 and March 2019. Patients with thymoma or thymic cyst and those aged less than 30 years were excluded. Thymic enlargement and thymus attenuation score in axial images of CT scans were quantitatively interpreted. We defined thymic enlargement as a thickness of more than 13 mm and graded the score by a four-point scale (score 0-3) according to previous studies [7, 8]. Association with radiographic thymus variants and clinical and immunological features was statistically analyzed.

Results

72 pSS and 47 PM/DM patients were enrolled. 90% and 63.8% were women and mean age was 62.7 ± 12.2 and 56.2 ± 13.7 years in pSS and PM/DM patients, respectively. Thymic enlargement was found in 16 (22.2%) and 14 (29.8%) patients with pSS and PM/DM, respectively. Thymus attenuation (score ≥ 2) was found in 11 (15.3%) and 9 (19.1%) patients with pSS and PM/DM, respectively. These findings were more frequent than in non-connective tissue diseases patients (9.1% and 9.1%, respectively). In pSS patients, radiographic thymus variants, both thymic enlargement and the thymus attenuation score, were significantly positively associated with body weight (P < 0.0073 and 0.037, respectively). Although there was no significant difference between immunological features such as titres of serum RF, the ratio of RF-positivity, SS-A antibody-positivity or SS-B antibody-positivity, and radiographic thymus variants, titres of serum RF tended to be positively associated with thymic enlargement (P = 0.057). In PM/DM patients, thymic enlargement was significantly positively associated with titres of serum RF (P = 0.046), and the thymus attenuation score was significantly positively associated with titres of serum IgG (P = 0.042) and significantly negatively associated with age (P = 0.033). There was no significant difference between the ratio of myositis specific antibody-positivity and radiographic thymus variants.

Conclusion

Radiographic thymus variants were frequently observed in pSS and PM/DM patients, and particularly, in case of PM/DM, may reflect an abnormal immune response involved in the pathogenesis.

References

[1]Gorozny JJ, et al. Trends Immunol 2001;22:251-255,

[2]Seddon B, et al. Immunol Today 2000;21:94-99,

[3]Truffault F, et al. Clin Rev Allergy Immunol 2017; 52:108-124,

[4]Berrih-Aknin S, et al. J Autoimmun 2014;52:90-110,

[5]Colaci M, et al. Rheumatology 2014;53:732-36,

[6]Murata O, et al. Rheumatology 2021;60:5595-5600,

[7]Ackman JB, et al. Radiology 2013;268:245-53,

[8]Naidich DP, et al. Philadelphia: Lippincott-Raven 1999:57-73.

Acknowledgements

I have no acknowledgements to declare.

Disclosure of Interests

None declared

Community pharmacists' measurement of health-related quality of life in outpatients taking high-risk drugs

Patients experiencing severe side effects when taking high-risk drugs may have a significantly reduced health-related quality of life (QOL); therefore, it is important to identify changes in the health-related QOL in these patients. This study aimed to determine the health-related QOL in community pharmacy outpatients taking high-risk drugs. This prospective observational study was conducted in 29 community pharmacies with 71 pharmacists in 12 regions and cities in Japan from October to December 2020 and 760 patients were enrolled. Using descriptive questionnaires of EuroQOL-5-dimensions-5-levels (EQ-5D-5L), community pharmacists obtained health-related QOL data from outpatients taking high-risk drugs. The mean health-related QOL of all outpatients was 0.869. The health-related QOL decreased with increasing age. The outpatient health-related QOL was 0.700, 0.763, 0.785, and 0.817 when taking antiepileptic, antidepressant, digitalis, and antiarrhythmic drugs, respectively, which was lower than the average health-related QOL of all outpatients. Mobility and pain/ discomfort accounted for a large proportion of the decline in the health-related QOL with increasing age. There were no significant differences in personal care with increasing age; however, the number of outpatients with mobility, normal activity, and pain challenges decreased with age. In contrast, outpatients aged <65 years with anxiety/depression showed a lower than overall average health-related QOL. To the best of our knowledge, this is the first study in Japan to report an investigation by community pharmacists regarding health-related QOL assessment in outpatients taking high-risk drugs.

POS0530 MOLECULAR SIGNATURE IN SUSTAINED CLINICAL REMISSION INDUCED BY TOCILIZUMAB IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background

Clinical remission is a clinical goal in the treatment of rheumatoid arthritis (RA). Sustained, biologics-free and true remission is an unachieved goal of the “treat-to-target” approach in most patients, and the determinants for achievement are still unclear. In our recent prospective study using multiomics analysis, we proposed that a molecular signature in peripheral whole blood can be a predictor for subsequent disease activity or activities of daily living.1 We also showed that tocilizumab (TCZ) induced deep clinical remission associated with gene expression in peripheral CD4+ T cells.2

Objectives

To consolidate and expand our hypothesis, we investigated the significance of molecular signatures in sustained remission in a larger scale cohort.

Methods

To build and validate the diagnostic model, we collected 73 peripheral blood samples from 30 patients with active RA, 30 patients in clinical remission induced by TCZ and 13 healthy controls. We then collected another 23 samples at a point before TCZ was halted due to sustained clinical remission. In total, 96 samples were analyzed by a multiomics platform, which included RNA sequencing and comprehensive proteomics.

Results

We first developed an optimized partial least-squares regression (PLSR) model using data from 5,436 genes and 255 proteins extracted in our previous model.1 The odds ratio in the model clearly reflected the clinical state with high fidelity (Figure 1). In that study, TCZ induced nearly half of the patients with clinical remission into molecular remission, with an odds ratio of less than zero. To clarify the characteristics of the molecular signature at sustained clinical remission under TCZ continuation, 23 samples were applied to the model. The odds ratio was largely the same as that for clinical remission. Next, we investigated the association with disease flare after cessation of TCZ. At some points before cessation, the median odds ratio in patients who experienced disease flare after stopping TCZ tended to be higher than that in patients with sustained remission after stopping TCZ in the transcriptomics model but not in the proteomics model. Thirty-five differentially expressed genes were identified between the two groups under the conditions of a >1.5-fold change and P-value<0.05.

Figure 1.

Odds ratio in the partial least-squares regression model using transcriptomics (A) and proteomics (B) data from rheumatoid arthritis and healthy control groups

Conclusion

Our larger scale study validated the idea in our previous study that TCZ induces molecular remission. A certain substantial gap associated with prognosis after quitting TCZ may exist as a molecular signature of sustained clinical remission induced by TCZ. These multiomics data sets enable us to understand sustained clinical remission at a molecular level.

References

[1]Nat Commun. 9(1):2775, 2018, 2) Sci Rep.11(1):16691, 2021

Graphs:

Acknowledgements

We acknowledge funding by Chugai Pharmaceutical Co., Ltd.

Disclosure of Interests

Nobuhiko Kajio: None declared, Katsuya Suzuki Speakers bureau: AbbVie, AsahiKasei, Astellas, Ayumi, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Gilead, Janssen, Mitsubishi Tanabe, Pfizer, Sanofi, Viatris, Consultant of: AbbVie, Asahi Kasei, Janssen, Pfizer, Grant/research support from: Chugai, Daiichi-Sankyo, Eli Lilly, Mitsubishi Tanabe, Ono, Takeda, Kotaro Matsumoto: None declared, Hiroshi Iijima: None declared, Seiji Nakamura: None declared, Yohei Ishizawa: None declared, Jun Inamo: None declared, Masaru Takeshita: None declared, Keiko Yoshimoto: None declared, Yuko Kaneko Speakers bureau: Chugai, Consultant of: Chugai, Grant/research support from: Chugai, Tsutomu Takeuchi Speakers bureau: Chugai, Consultant of: Chugai, Grant/research support from: Chugai.

POS0459 APTAMER-BASED PROTEOMIC SCREENING IN IDENTIFICATION OF PATHOGENIC SIGNAL PATHWAY AND URINARY BIOMARKERS ASSOCIATED WITH HISTOLOGICAL FINDINGS IN LUPUS NEPHRITIS

Background

The current gold standard for the diagnosis and classification, assessment of the severity of lupus nephritis (LN) is a renal biopsy. On the other hand, since the procedure is highly invasive, there is a pressing need to identify biomarkers for predicting the presence and its histological severity of LN. In addition, the background pathogenesis of each histological findings is not clearly understood.

Objectives

The purpose of this study was to elucidate the urine biomarkers for predicting the presence and the severity of histological findings of LN, and to search the pathogenic signal pathway.

Methods

Urine samples from 24 biopsy-proven active LN patients were initially screened for the levels of 1305 distinct human proteins using an aptamer-based-targeted proteomic assay. We developed histological scoring system based on ISN/RPS lesion definitions and classification, NIH activity and chronicity score. Two experienced evaluators assessed the histological scores. Cluster analysis and pathway analysis were performed.

Results

A total of 24 LN patients were included: 20 (83%) had a proliferative histological class (III or IV +/-V), 4 (17%) pure membranous (V). Through cluster analysis, several histological subgroups were extracted according to correlation with each histological finding, and proteins which corelated with each histological scores were analyzed. We focused on two subgroups: one in which including active glomerular histological findings (endocapillary hypercellularity, karyorrhexis, neutrophil infiltration, subendothelial deposits) and the other in which including interstitial histological findings (interstitial inflammation, interstitial fibrosis, tubular atrophy). Histological scores in the former group showed strong positive correlation with protein group which contained 59 proteins (Group A), including CCL21, CXCL10, VCAM1. Histological scores in the latter group corelated with another protein group which contained 85 proteins (Group B), including MCP-1, CCL11. Ingenuity Pathway Analysis showed 16 pathways (PDGF Signaling, Granulocyte Adhesion and Diapedesis, etc) were upregulated in Group A and 11 pathways (IL-17 signaling, Fibrosis signaling pathway, etc) upregulated in Group B. Among group A and group B urine proteins, those showed strong correlation between respective histological findings were validated with ELISA assays.

Conclusion

An aptamer-based-targeted proteomic assay screening by combining with renal histological scoring system suggested several urine proteins can predict the severity and the presence of major renal histological findings, and suggested to be related with the pathogenesis in patients with LN.

Disclosure of Interests

Kazuoto Hiramoto: None declared, Shuntaro Saito: None declared, Hironari Hanaoka: None declared, Katsuya Suzuki: None declared, Jun Kikuchi: None declared, Hiroyuki Fukui: None declared, Ryo Takano Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Fumihiko Miyoshi Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Noriyasu Seki Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Kunio Sugahara Employee of: Mitsubishi Tanabe Pharma Corporation Sohyaku, Yuko Kaneko: None declared, Tsutomu Takeuchi: None declared.

POS0257 COMPARISON OF SARS-CoV-2 VACCINE RESPONSE IN PATIENTS WITH INFLAMMATORY RHEUMATIC DISEASE; mRNA-1273 VACCINE INDUCES HIGHER HUMORAL IMMUNOGENICITY THAN BNT162b2

Background

The SARS-CoV-2 messenger RNA (mRNA) vaccines BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) have benefitted all countries amid the coronavirus disease 2019 (COVID-19) crisis. Whereas both of them have shown efficacy in preventing COVID-19 illness in healthy participants, there is paucity of data about immunogenicity and safety of mRNA COVID-19 vaccines in patients with autoimmune, inflammatory rheumatic disease. Recent observational studies evaluated mainly BNT162b2, suggesting that glucocorticoids, immunosuppressive agents impair SARS-CoV-2 vaccine responses. However, difference in immune reactions and safety between BNT162b2 and mRNA-1273 have not been clarified in patients with inflammatory rheumatic diseases.

Objectives

To assess humoral and T cell immune responses and safety profiles after two doses of different mRNA vaccine against SARS-CoV-2; BNT162b2 and mRNA-1273.

Methods

We enrolled consecutive, previously uninfected patients with inflammatory rheumatic diseases receiving mRNA vaccine including BNT162b2 and mRNA-1273. Healthy participants receiving BNT162b2 were also recruited as control. Blood samples were obtained 3weeks, 2 months, 3 months, 4 months, and 6 months after second dose of vaccines. We measured titres of neutralizing antibodies against SARS-CoV-2 and calculated seroconversion rates to evaluate humoral responses. We also assessed T-cell immunity responses by using interferon releasing assay against SARS-CoV-2 in a part of the patients. Answers to questionnaires about adverse reactions were obtained from participants.

Results

A total of 974 patients with inflammatory rheumatic diseases and healthy 630 control participants were enrolled. Among them, 796 patients received BNT162b2, 178 patients received mRNA-1273, and all control participants received BNT162b2. Seroconversion rates and neutralizing antibody titres 3 weeks after vaccination were significantly higher in patients with mRNA-1273 and healthy participants with BNT162b2 compared with patients with BNT162b2; seroconversion rates, 97.2% vs 99.5% vs 83.3%, p<0.001; titers of neutralizing antibodies, 29.4±33.9 IU/mL vs 23.9±14.2 IU/mL vs 10.8±16.5 IU/mL, p<0.001, respectively. On another front, T cell reaction against SARS-CoV-2 was similar in both patients with mRNA-1273 and BNT162b2; interferon gamma levels for antigen 1, 1.2±2.1 IU/mL vs 0.8±2.5 IU/mL, p=0.23; and for antigen 2, 1.4±1.9 IU/mL vs 1.0±2.1 IU/mL, p=0.11, respectively. Regarding adverse reaction of each mRNA vaccine, the frequency of systemic adverse reactions including fever and general fatigue are also significantly higher in patients with mRNA-1273 and healthy controls than patients with BNT162b2; fever, 48.0% vs 44.9% vs 10.2%, p<0.001; general fatigue, 70.4% vs 61.8% vs 31.2%, p<0.001, respectively). In longitudinal measurement, neutralizing antibody titres in patients with BNT162b2 were decreased more rapidly than those in healthy controls; 3.3±3.2 IU/mL in patients with BNT162b2 at 4 months and 3.2±4.7 IU/mL in healthy controls with BNT162b2 at 6 months. We identified age, glucocorticoid dose (prednisolone > 7.5mg), use of immunosuppressants including methotrexate, mycophenolate, cyclophosphamide, and tacrolimus are associated with rapid attenuation of humoral responses in patients with BNT162b2.

Conclusion

Our results demonstrated a significant higher humoral immunogenicity and frequency of systemic adverse reaction of the SARS-CoV-2 mRNA-1273 (Moderna) compared with the BNT162b2 (Pfizer-BioNTech) in inflammatory rheumatic disease patients. Glucocorticoid and immunosuppressive agents impaired induction and sustention of neutralizing antibody, and earlier third booster vaccination may be required within 4 months, especially for those receiving BNT162b2.

References

[1]Steensels D, Pierlet N, Penders J et al. JAMA. 2021;326(15):1533–1535.

[2]Friedman MA, Curtis JR and Winthrop KL. Ann Rheum Dis 2021;80:1255–1265.

Disclosure of Interests

None declared

Measurements of Strong-Interaction Effects in Kaonic-Helium Isotopes at Sub-eV Precision with X-Ray Microcalorimeters

We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst)  eV and 6463.7±0.3(stat)±0.1(syst)  eV, and widths to be 2.5±1.0(stat)±0.4(syst)  eV and 1.0±0.6(stat)±0.3(stat)  eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.

Habitual exercise provides better prognosis for cardiac arrest with coronary artery disease

Background

Although regular physical activity has beneficial cardiovascular effects, exercise can trigger sudden cardiac arrest (SCA). Coronary artery disease (CAD) was identified as the most common cause of an exercise-related out-of-hospital cardiac arrest (OHCA). Regular exercise has been reported to reduce the risk of plaque rupture in animal studies and basic research. Therefore, we compared the coronary artery findings in CAD-OHCA patients with and without habitual exercise.

There have been few reports on whether regular exercise changes the prognosis in OHCA due to CAD (CAD-OHCA). We investigated the association between the better clinical outcome and the regular exercise in patients with CAD-OHCA.

Methods

This is a single-center retrospective analysis from 2006 to 2019. The consecutive 397 patients with OHCA due to myocardial ischemia underwent coronary angiography (CAG). After excluding 73 patients with vasospastic angina, the remaining 324 patients with CAD were enrolled in this study. We divided these patients into two groups according to whether they were habitually exercising (Exercise group: N=37) or not/unknown (Non-Exercise group: N=287).

Clinical outcome was a 30-day survival with minimal neurologic impairment represented by a Glasgow-Pittsburgh Cerebral Performance Categories Scale value 1 or 2.

Results

The patients in the Exercise Group were significantly younger (exercise vs. non-exercise, 57±12 vs. 64±12 years; P&lt;0.01) than those in the non-exercise group. The Exercise group had a lower incidence of diabetes mellitus (22% vs. 42%; P=0.02) and a higher incidence of dyslipidemia (81% vs. 62%; P=0.02) than the non-exercise group. The time from collapse to cardiopulmonary resuscitation (1.4±4.0 vs. 3.0±4.8min) and from collapse to return of spontaneous circulation (11.9±10.0 vs. 28.0±25.3min) were shorter in Exercise group (all p&lt;0.05). The ST-segment elevation was recorded on electrocardiography in fewer of the Exercise group (22% vs. 63%; P&lt;0.01). The finding of culprit lesion in the coronary arteries on arrival resulted significant differences between the 2groups (good collateral and/or TIMI3 flow: 62% vs. 25%, the plaque rupture and/or thrombus: 22% vs. 73%) (all p&lt;0.01) (Figure 1). Kaplan-Meier curve showed Exercise group has better neurological outcome at 30days compared than Non-Exercise (95% vs 51%; P&lt;0.001, log-rank test) (Figure 2). Multivariable Cox proportional hazards models revealed that a habitual exercise was one of the predictors of a good neurological outcome (HR 0.21, 95% CI 0.05–0.92; P=0.039).

Conclusions

The patients with habitual exercise had less plaque rupture, less coronary thrombosis than non-exercise. The patients with regular exercise had better clinical outcomes than non-exercise after CAD-OHCA.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Tokyo Metropolitan Goverment Figure 1. Findings of the culprit lesion in coronar arteriesFigure 2. Kaplan-Meier analysis

Isolation of Rhodococcus equi from the gastrointestinal contents of earthworms (family Megascolecidae)

Rhodococcus equi was isolated from the gastrointestinal contents of earthworms (family Megascolecidae) and their surrounding soil collected from pastures of two horse-breeding farms in Aomori Prefecture, outdoor pig pens, forest in Towada campus, orange groves and forest where wild boars (Sus scrofa) are established in Tanabe, Wakayama Prefecture. The number of R. equi in the lower gastrointestinal contents of 23 earthworms collected from our campus was significantly larger than that of the upper gastrointestinal content. The mean numbers of R. equi from the gastrointestinal contents of earthworms collected from the various places were 2·3-fold to 39·7-fold more than those of the surrounding soil samples. In all, 1771 isolates from the earthworms and 489 isolates from the soil samples were tested for the presence of vapA and vapB genes using polymerase chain reaction. At the horse-breeding farm N, 9 of the 109 isolates (8·3%) from the earthworms and 7 of the 106 isolates (6·6%) from the soil samples were positive for the vapA gene. At the University's forest, one of the 250 isolates (0·4%) from the gastrointestinal contents of the earthworm was positive for the vapB gene. These results revealed that R. equi can be found in significant quantities in the gastrointestinal contents of earthworms, suggesting that they act as an accumulator of R. equi in the soil environment and as a source or reservoir of animal infection.

A Japanese Multicenter Study on PET and Other Biomarkers for Subjects with Potential Preclinical and Prodromal Alzheimer's Disease

BACKGROUND

PET (positron emission tomography) and CSF (cerebrospinal fluid) provide the "ATN" (Amyloid, Tau, Neurodegeneration) classification and play an essential role in early and differential diagnosis of Alzheimer's disease (AD).

OBJECTIVE

Biomarkers were evaluated in a Japanese multicenter study on cognitively unimpaired subjects (CU) and early (E) and late (L) mild cognitive impairment (MCI) patients.

MEASUREMENTS

A total of 38 (26 CU, 7 EMCI, 5 LMCI) subjects with the age of 65-84 were enrolled. Amyloid-PET and FDG-PET as well as structural MRI were acquired on all of them, with an additional tau-PET with 18F-flortaucipir on 15 and CSF measurement of Aβ1-42, P-tau, and T-tau on 18 subjects. Positivity of amyloid and tau was determined based on the positive result of either PET or CSF.

RESULTS

The amyloid positivity was 13/38, with discordance between PET and CSF in 6/18. Cortical tau deposition quantified with PET was significantly correlated with CSF P-tau, in spite of discordance in the binary positivity between visual PET interpretation and CSF P-tau in 5/8 (PET-/CSF+). Tau was positive in 7/9 amyloid positive and 8/16 amyloid negative subjects who underwent tau measurement, respectively. Overall, a large number of subjects presented quantitative measures and/or visual read that are close to the borderline of binary positivity, which caused, at least partly, the discordance between PET and CSF in amyloid and/or tau. Nine subjects presented either tau or FDG-PET positive while amyloid was negative, suggesting the possibility of non-AD disorders.

CONCLUSION

Positivity rate of amyloid and tau, together with their relationship, was consistent with previous reports. Multicenter study on subjects with very mild or no cognitive impairment may need refining the positivity criteria and cutoff level as well as strict quality control of the measurements.

Cost-effectiveness of primary prophylaxis of febrile neutropenia with pegfilgrastim in docetaxel, cisplatin and 5-fluorouracil therapy for esophageal cancer

Objective: The efficacy of docetaxel, cisplatin, and 5-fluorouracil (DCF) therapy in treating esophageal cancer has been reported. However, febrile neutropenia (FN) is a potentially serious adverse event of DCF therapy with an incidence of 10 to 40%. Pegfilgrastim, a granulocyte colony-stimulating factor (G-CSF), has been shown to have a primary prophylactic role in FN. However, it has been suggested that excessive use of expensive G-CSF should be avoided. Therefore, we performed a cost-utility analysis of primary prophylaxis with pegfilgrastim. Design: Cost-effectiveness analysis using decision tree modelling. Methods: We used a decision tree analysis model based on the report of primary prophylaxis with pegfilgrastim. Based on a previous study, the FN incidence rate was set at 40.0% (95% confidence interval (CI): 11.9-68.1) for the pegfilgrastim group and 43.5% (95%CI: 21.6-65.4) for the no pegfilgrastim group. The FN treatment cost was US$726.63, and the duration of FN was 3.65±1.20 days. The utility value of patients who received DCF therapy was 0.643, and the change in utility value at FN onset was -0.15. Expected cost, quality-adjusted life year (QALY), and incremental cost-effectiveness ratio (ICER) were calculated, and cost-utility analysis was performed. Results: The ICER of pegfilgrastim was 184,976.75 USD/QALY. As a result of sensitivity analysis, the utility of FN had the greatest impact on the cost-effectiveness analysis, followed by the drug cost of pegfilgrastim. Conclusion: Primary prophylaxis of FN with pegfilgrastim might not be cost-effectiveness. In determining whether to administer pegfilgrastim it is necessary to consider patient factors, not just the incidence of FN.

Activation of the mitogen-activated protein kinase ERK1/2 signaling pathway suppresses the expression of ChREBPα and β in HepG2 cells

The carbohydrate response element‐binding protein (ChREBP), a glucose‐responsive transcription factor that plays a critical role in the glucose‐mediated induction of genes involved in hepatic glycolysis and lipogenesis, exists as two isoforms: ChREBPα and ChREBPβ. However, the mechanism responsible for regulating the expression of both ChREBPα and β, as well as the mechanism that determines which specific isoform is more responsive to different stimuli, remains unclear. To address this issue, we compared the effects of several stimuli, including oxidative stress, on the mRNA and protein expression levels of ChREBPα and β in the hepatocyte cell line, HepG2. We found that H₂O₂ stimulation suppressed the expression of both mRNA and protein in HepG2 cells, but the mRNA expression level of ChREBPβ was < 1% of that for ChREBPα levels. In addition, the reduction in both ChREBPα and β mRNA levels was reversed by PD98059, a selective and cell permeable inhibitor of the MEK/ERK pathway. Additionally, the administration of 12‐O‐tetradecanoylphorbol 13‐acetate (TPA) and staurosporine (STS), activators of extracellular‐signal‐regulated kinase (ERK) signaling, also resulted in a decrease in the levels of both ChREBPα and β mRNA in HepG2 cells through ERK signaling. These collective data suggest that oxidative stress, including STS treatment, suppresses the expression of ChREBPα and β via the activation of ERK signaling in HepG2 cells. Such a decrease in the levels of expression of ChREBPα and β could result in the suppression of hepatic glycolysis and lipogenesis, and this would be expected to prevent further oxidative stress.

POS0527 ACUTE KIDNEY INJURY (AKI) IN PATIENTS WITH RHEUMATOID ARTHRITIS (RA)

Background:

Methotrexate has been an anchor drug for patients with rheumatoid arthritis (RA). However, it is strictly prohibited to prescribe MTX to patients with severely decreased renal function because it can induce a fatal adverse event such as pancytopenia in these patients. On the other hand, since the average age of RA patients is gradually increasing, and many of them already have mildly to moderately impaired renal function, their renal function can easily decrease to below the critical level of the estimated glomerular filtration rate. Therefore, new development of acute kidney injury (AKI) during MTX administration might induce a fatal adverse event, making the identification of patients susceptible to AKI very important.

Objectives:

To clarify the frequency of AKI and the factors involved in it in RA patients.

Methods:

Two hundred and fifty-two RA patients (211 females, 41 males, mean age 62.3 ± 12.5 years, disease duration 11.0 ± 9.5 years) diagnosed more than 3 years earlier and followed for more than 5 years, and also, others diagnosed ≥3 years earlier but followed for ≤5 years were enrolled. We measured BUN, Cr, RF and aCCP in patient serum, urinary proteins, urinary blood, and urinary casts and evaluated CDAI, SDAI, disease activity score (DAS) 28-CRP and DAS28-ESR. Steinbrocker functional classification and radiological grading were evaluated. History of diabetes mellitus, hypertension and hyperlipidemia was determined from the medical records. Medications for RA, including non-steroid anti-inflammatory drugs (NSAIDs), prednisolone, csDMARD (MTX, Tacrolimus, etc.), bDMARDs and tsDMARDs were evaluated. Estimated glomerular filtration rate (eGFR) was calculated by the new Japanese coefficient-modified Modification of Diet in Renal disease (MDRD) study equation. The criteria of AKI were that serum Cr increased by 0.3 mg /dl or increased by 1.5-fold between consecutive visits according to the KIDIGO criteria 1) and the report of Leither et al2).

Results:

Twenty (7.9%) patients developed AKI, 22 times. The causes of AKI were 10 infections, 6 dehydrations, 2 enteritis, 1 urticaria, 2 hypercalcemia due to VitD administration, and 1 ureteral stone. We divided our patients into group A (with AKI) and group B (without AKI). Group A was older (69.9±10.1 vs 61.7±12.6 years), had greater physician VAS (29.5±27.7 vs 15.7±18.3 mm), higher serum creatinine (0.79±0.19 vs 0.60±0.16 mg/dl), higher BUN (18.4±5.7 vs 15.1±4.4 mg/dl), lower eGFR(65.5±23.3 vs 86.4±22.4 ml/min), more frequent prednisolone administration (75.0% vs 41.9%), more frequent hyperlipidemia (50.0% vs 19.2%) and more frequent hypertension (60.0% vs 30.6%) than Group B by univariate analysis significantly (p<0.01). We then performed multifactorial analysis using logistic regression analysis. Greater physician VAS (OR 1.02, 1.00-1.04), lower eGFR (OR 1.04, 1.01-1.08) and prednisolone administration (OR 3.29, 1.02-10.63) were found as independent relevant factors for group A.

Conclusion:

Our study indicated that AKI developed in RA patients and suggested that renal function decline and prednisolone administration may be implicated. RA patients with impaired renal function and prednisolone administration need to be treated with special attention to the onset of AKI.

References:

[1]Kidney Disease: Improving Global Outcomes (KDIGO) Practice Guideline for Acute Kidney Injury. Kidney Int Suppl 2: 1-138, 2012

[2]Leither MD, Murphy DP, Bicknese L et al. The impact of outpatient acute kidney injury on mortality and chronic kidney disease: a retrospective cohort study. Nephrol Dial Transplant. 34:493-501, 2019

Disclosure of Interests:

None declared

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