Predictability of noninvasive liver fibrosis score for cardiac events in patients with nonalcoholic fatty liver disease.

BACKGROUND AND AIMS: Patients with nonalcoholic fatty liver disease (NAFLD) have a higher risk of cardiac events. However, although the severity of liver fibrosis is related to worsening prognosis in patients with NAFLD, it is unclear whether the noninvasive liver fibrosis score has a predictive value for cardiac events. METHODS AND RESULTS: We evaluated 4071 patients with NAFLD diagnosed using ultrasonography. Liver fibrosis was assessed and divided into three groups based on the Fibrosis-4 (FIB4) index and NAFLD fibrosis score (NFS). The primary outcome of this study was major adverse cardiac events (MACE), including cardiac death, nonfatal myocardial infarction, and revascularization due to coronary artery disease. The median age of the evaluated patients was 61 (52-69) years, and 2201 (54.1%) were male. During the median follow-up period of 6.6 years, 179 (4.4%) patients experienced MACE. Kaplan-Meier survival analysis demonstrated that MACE increased progressively with the FIB4 index (log-rank, p < 0.001) and NFS (log-rank, p < 0.001). Multivariable analysis showed that the higher the FIB4 index, the higher the risk for MACE (low group as reference vs. intermediate group, hazard ratio [HR]: 1.860 [95% confidence interval (CI), 1.326-2.610; p < 0.001]; vs. high group, HR:3.325 [95% CI, 2.017-5.479; p < 0.001]), as well as NFS (low NFS group as reference vs. intermediate group, HR: 1.938 [95% CI, 1.391-2.699; p < 0.001]; vs. high group, HR: 3.492 [95% CI, 1.997-6.105; p < 0.001]). CONCLUSIONS: The FIB4 index and NFS are associated with the probability of MACE in patients with NAFLD. CLINICAL TRIALS: The study design was approved by the ethics review board of Ogaki Municipal Hospital (approval number: 20221124-12, registration date: November 28th, 2022). https://www.ogaki-mh.jp/chiken/kenkyu.html.

Clinical Value of Troponin Levels to Cardiac Function and Prognosis in Patients with Fulminant Myocarditis.

Troponin (Tn) is a biomarker related to myocardial necrosis and is elevated in patients with myocarditis. This study aimed to investigate the association between cardiac Tn levels and the course of cardiac function, and prognosis in patients with fulminant myocarditis (FM) receiving percutaneous mechanical circulatory support (MCS).We used data from a multicenter retrospective registry, CHANGE PUMP 2, which included 216 patients with FM who required MCS. Among them, 141 patients whose Tn levels were available were analyzed. The patients were divided into low and high Tn groups according to the median values of TnT and TnI.The median age was 54 years, and 59.6% were male. The TnT and TnI on day 1 (at MCS initiation) were 3.8 (1.4-10.0) and 21.4 (8.4-68.8) ng/mL. While the left ventricular ejection fraction (LVEF) was similar on day 1 (25.0% versus 24.5%), the low Tn group showed better LVEF improvement on day 7 than the high Tn group (45.0% versus 25.3%, P < 0.001). LVEF at 1 year after admission was higher in the low Tn group (65.0% versus 59.7%, P = 0.039). The low Tn group had a better 90-day composite endpoint in death, durable left ventricular assist device implantation, and heart transplantation compared to the high Tn group (hazard ratio 0.47, 95% CI 0.23-0.95).Tn levels were associated with short- and long-term cardiac recovery and adverse outcomes in patients with FM receiving MCS due to cardiogenic shock.

Analysis of Adverse Events Associated with Trastuzumab Deruxtecan in Patients with Gastric and Breast Cancer: A Retrospective Study.

Trastuzumab deruxtecan (T-DXd) has displayed demonstrable efficacy and manageable toxicity in previously treated patients with advanced gastric and breast cancer, and it has been approved in Japan. However, there is a lack of data on the optimal management in clinical practice. Therefore, we assessed the adverse event (AE) profiles of T-DXd in patients with advanced gastric or breast cancer to provide guidance for appropriate management. This retrospective study was conducted at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research. We reviewed the medical records of patients with advanced gastric or breast cancer who received T-DXd between May 2020 and December 2021. AEs occurring within the first three cycles of T-DXd were evaluated according to Common Terminology Criteria for Adverse Events version 5.0. Thirty-six patients were enrolled (gastric: n = 19, breast: n = 17). All 15 males had gastric cancer, whereas 4 and 17 females had gastric and breast cancer, respectively. Interstitial lung disease (ILD) occurred in five patients (14%), but no patients had severe ILD. Gastrointestinal (GI) toxicities, including nausea (61%), vomiting (22%), decreased appetite (33%), and diarrhea (39%), were the most common AEs. The incidence of GI toxicities did not differ by cancer type; however, nausea was significantly more common in females (81 vs. 33%; p < 0.01). T-DXd was safely administered in clinical practice in patients with previously treated advanced gastric or breast cancer. The management of GI toxicities is important in the clinical implementation of T-DXd.

Clinical features, future cardiac events, and prognostic factors following percutaneous coronary intervention in young female patients.

BACKGROUND: The proportion of young females among the patients who undergo percutaneous coronary intervention (PCI) is relatively small, and information on their clinical characteristics is limited. This study investigated the clinical characteristics and prognostic factors for future cardiac events in young females who underwent PCI. METHODS: This multicenter observational study included 187 consecutive female patients aged < 60 years who underwent PCI in seven hospitals. The primary composite endpoint was the incidence of cardiac death, nonfatal myocardial infarction, and target vessel revascularization. RESULTS: The mean patient age was 52.1 ± 6.1 years and 89 (47.6%) had diabetes, and renal dysfunction (an estimated glomerular filtration rate < 60 mL/min/1.73 m2) was observed in 38 (20.3%). During a median follow-up of 3.3 years, the primary endpoint occurred in 28 patients. The Cox proportional hazards models showed that renal dysfunction was an independent predictor for the primary endpoint (hazard ratio 3.04, 95% confidence interval 1.25-7.40, p = 0.01), as well as multivessel disease (hazard ratio 2.79, 95% confidence interval 1.12-6.93, p = 0.03). Patients with renal dysfunction had a significantly higher risk for the primary endpoint than those without renal dysfunction. CONCLUSIONS: Renal dysfunction was strongly associated with future cardiac events in young females who underwent PCI.

Factors associated with lenvatinib adherence in thyroid cancer and hepatocellular carcinoma.

BACKGROUND: Lenvatinib is an oral anticancer medication used to treat radioiodine-refractory thyroid cancer and unresectable hepatocellular carcinoma. The purpose of this study is to evaluate lenvatinib adherence by patients and to identify factors associated with decreased lenvatinib adherence. METHODS: Among 153 patients who started treatment with lenvatinib for unresectable thyroid cancer or unresectable hepatocellular carcinoma between May 1, 2015 and August 31 2021 at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research, 102 were eligible for this study (55 thyroid cancer, 47 hepatocellular carcinoma). The lenvatinib adherence rate in a treatment cycle was defined as the number of times a patient took lenvatinib in a 28-day cycle divided by the prescribed 28 doses. The rate was determined by pill counting and self-reporting at the pharmaceutical outpatient clinic. Reasons for non-adherence were established by interview and analyzed. RESULTS: The median adherence rate of lenvatinib in the first cycle was 90.1% (n = 55) in thyroid cancer and 94.9% (n = 47) in hepatocellular carcinoma. In thyroid cancer, there were 255 incidents of lenvatinib non-adherence. Non-adherence was mainly associated with bleeding events (18.6%), followed by hand-foot skin reactions (10.6%). In hepatocellular carcinoma, there were 97 incidents of non-adherence. Hypertension accounted for 20.6%, followed by hoarseness (18.6%) and diarrhea (17.5%). CONCLUSION: The adherence rate for lenvatinib in Japanese patients with thyroid and hepatocellular carcinoma in real-world clinical practice was more than 90% in this study. Hypertension was a major reason for non-adherence, followed by hand-foot skin reactions and diarrhea.

The "via dialysis circuit" external bypass technique: External femoral to femoral bypass via dialysis circuit for antegrade perfusion of the ischemic limb.

A 71-year-old woman with no relevant previous medical history presented to the emergency department with cardiopulmonary arrest due to extensive myocardial infarction. Veno-arterial extracorporeal life support (ECLS) was passed through the right common femoral artery (CFA), and an Impella CP® (16-F introduction sheath, Abiomed Inc., Danvers, MA, USA) was inserted from the left CFA. Although these mechanical devices provide powerful cardiac and organ support, an occlusive large-bore sheath may induce ischemic limb complications. Antegrade flow from the contralateral sheath was circulated through the ECLS circuit, showing the improvement of antegrade left SFA. Cardiac function improved after primary percutaneous coronary intervention, but when the ECLS was terminated, antegrade left limb flow declined. Hence, we bypassed the contralateral flow via the dialysis circuit and prevented limb ischemia. Learning objective: Although an Impella® (Abiomed Inc., Danvers, MA, USA) is useful for assisting left ventricular cardiac function, its large-bore sheath sometimes disturbs the antegrade flow, resulting in ischemic limb complications. A novel yet simple technique that involves an external bypass through the superficial femoral artery to provide antegrade perfusion to the ipsilateral limb is hereby described.

Elevated liver fibrosis-4 index predicts recurrence after catheter ablation for atrial fibrillation in patients with heart failure.

BACKGROUND: The fibrosis-4 (FIB-4) index is a noninvasive scoring system that is used to assess the progression of liver fibrosis. This study aimed to assess whether the FIB-4 index is associated with recurrent atrial fibrillation (AF) after catheter ablation in patients with and without heart failure (HF). METHODS: We included 1,184 patients who underwent initial AF catheter ablation between 2016 and 2021. The patients were classified into low-risk (< 1.3), intermediate-risk (1.3-2.67), and high-risk (> 2.67) groups based on their FIB-4 indices at baseline. The patients were divided into HF (n = 552) and non-HF groups (n = 632); the HF group was further divided into paroxysmal AF (PAF) and non-PAF groups. AF recurrence after catheter ablation was then compared among the groups. RESULTS: In the non-HF group, no significant differences in recurrence after ablation were observed between the low-(n = 219), intermediate-(n = 364), and high-risk (n = 49) groups. In contrast, in the HF group, the intermediate-(n = 341) and high-risk (n = 112) groups had significantly higher recurrence rates than the low-risk group (n = 99) (log-rank test, p = 0.005). This association remained significant after multivariate analysis (hazard ratio [HR]:1.374; p = 0.027). The FIB-4 index increased incrementally as the brain natriuretic peptide levels and severity of tricuspid regurgitation increased. The FIB-4 index was an independent predictor of recurrence in the non-PAF HF group (HR:1.498; p = 0.007) but not in the PAF group. CONCLUSIONS: The FIB-4 index may be a useful predictor of AF recurrence after catheter ablation in patients with HF, particularly in those with non-PAF.

Association Between Catheter Ablation for Nonparoxysmal Atrial Fibrillation and Functional Mitral Regurgitation in Patients With Heart Failure With Preserved Ejection Fraction.

Functional mitral regurgitation (FMR) often coexists with atrial fibrillation (AF) and may have a causal relation with AF persistence and exacerbation of heart failure (HF). The purpose of this study was to investigate the impact of FMR on AF catheter ablation (AFCA) outcomes and improvement in FMR after AFCA in patients with HF with preserved ejection fraction (HFpEF) and nonparoxysmal AF. Excluding patients with primary valve disease or post-mitral valve repair, 280 patients with HFpEF who underwent CA for nonparoxysmal AF were retrospectively included. All patients completed 1-year follow-up and were assessed for FMR, AF recurrence and HF parameters, including echocardiography. At baseline, FMR was present in 153 (54.6%) patients (mild, n = 112; moderate, n = 40; severe, n = 1), and these were decreased to 70 (25%) significantly 1 year after AFCA (mild, n = 64; moderate, n = 6), 119 patients (78%) had improvement in MR (a decrease of ≥1 level in the severity from baseline to 1 year on echocardiography). Overall, 274 patients (97.9%) had sinus rhythm at the 1-year examination, and recurrent AF-free survival did not differ in patients with and without MR improvement (83.2% vs 82.4%, p = 0.908). However, the MR improvement group had a significantly lower cardiothoracic ratio, left atrial diameter, E/e', and B-type natriuretic peptide levels after 1 year than those in the MR nonimprovement group. In conclusion, the majority of the HFpEF patients with nonparoxysmal AF had improvement of FMR after AFCA with the high maintenance of sinus rhythm, leading to a virtuous cycle of cardiac function.

Serum Creatinine Elevation as a Risk Factor for Niraparib-induced Hematologic Toxicity.

BACKGROUND/AIM: Niraparib dosages can be individualized to reduce the starting dose based on body weight and baseline platelet count. However, even with individualized dosing, scattered cases of ≥Grade 3 hematologic toxicity occur. This study explored markers predictive of serious hematologic toxicity in niraparib therapy. PATIENTS AND METHODS: This retrospective observational study investigated patients who started niraparib therapy at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research between December 2020 and March 2022. Associations between hematologic toxicities and serum creatinine ratio (percentage increase in serum creatinine between baseline and after niraparib initiation) were investigated. RESULTS: Out of 50 ovarian cancer patients who initiated niraparib, 45 patients were included in the final analysis. Twenty-three patients (51.1%) developed ≥Grade 3 hematologic toxicity, with neutropenia in 17 (37.8%), anemia in 9 (20.0%), and thrombocytopenia in 4 (8.9%). Patients with Grade 4 hematologic toxicity showed higher serum creatinine ratios than those with ≤Grade 2. Thrombocytopenia ≥Grade 3 occurred only within 2 months of niraparib initiation and was preceded by an increase in serum creatinine in all affected patients. CONCLUSION: Serum creatinine ratio offers a potential marker for predicting severe hematologic toxicity following niraparib therapy.

Impact of right coronary artery dominance on the long-term mortality in the patients with acute total/subtotal occlusion of unprotected left main coronary artery.

BACKGROUND: Patients with a right dominant coronary artery anatomy account for a significant proportion of acute myocardial infarction cases, and this condition is associated with a better prognosis. However, there are limited data on the impact of coronary dominance on patients with acute total/subtotal occlusion of unprotected left main coronary artery (ULMCA). METHODS: This study aimed to assess the impact of right coronary artery (RCA) dominance on long-term mortality in patients with acute total/subtotal occlusion of the ULMCA. From a multicenter registry, 132 cases of consecutive patients who had undergone emergent percutaneous coronary intervention (PCI) due to acute total/subtotal occlusion of the ULMCA were reviewed. RESULTS: Patients were classified into two groups according to the size of their RCA (dominant RCA group, n = 29; non-dominant RCA group, n = 103). Long-term outcomes were examined according to the presence of dominant RCA. Cardiopulmonary arrest (CPA) occurred in 52.3 % of patients before revascularization. All-cause death was significantly lower in the dominant RCA group than in the non-dominant RCA group. In the Cox regression model, dominant RCA was an independent predictor of all-cause death, as well as total occlusion of ULMCA, collateral from RCA, chronic kidney disease, and CPA. Patients were further analyzed according to the degree of stenosis of the ULMCA; patients with non-dominant RCA and total occlusive ULMCA had the worst outcome compared with the other groups. CONCLUSIONS: A dominant RCA might improve long-term mortality in patients with acute total/subtotal occlusion of the ULMCA who were treated with PCI.

Structural Basis for the Activation of the Cobalt-Carbon Bond and Control of the Adenosyl Radical in Coenzyme B12 Catalysis.

Adenosylcobalamin (AdoCbl), or coenzyme B12 , is a naturally occurring organometallic compound that serves as a cofactor for enzymes that catalyze intramolecular group-transfer reactions and ribonucleotide reduction in a wide variety of organisms from bacteria to animals. AdoCbl-dependent enzymes are radical enzymes that generate an adenosyl radical by homolysis of the coenzyme's cobalt-carbon (Co-C) bond for catalysis. How do the enzymes activate and cleave the Co-C bond to form the adenosyl radical? How do the enzymes utilize the high reactivity of the adenosyl radical for catalysis by suppressing undesirable side reactions? Our recent structural studies, which aimed to solve these problems with diol dehydratase and ethanolamine ammonia-lyase, established the crucial importance of the steric strain of the Co-C bond and conformational stabilization of the adenosyl radical for coenzyme B12 catalysis. We outline here our results obtained with these eliminating isomerases and compare them with those obtained with other radical B12 enzymes.

Environmental DNA phylogeography: Successful reconstruction of phylogeographic patterns of multiple fish species from cups of water.

Phylogeography is an integrative field of science linking micro- and macro-evolutionary processes, contributing to the inference of vicariance, dispersal, speciation, and other population-level processes. Phylogeographic surveys usually require considerable effort and time to obtain numerous samples from many geographical sites covering the distribution range of target species; this associated high cost limits their application. Recently, environmental DNA (eDNA) analysis has been useful not only for detecting species but also for assessing genetic diversity; hence, there has been growing interest in its application to phylogeography. As the first step of eDNA-based phylogeography, we examined (1) data screening procedures suitable for phylogeography and (2) whether the results obtained from eDNA analysis accurately reflect known phylogeographic patterns. For these purposes, we performed quantitative eDNA metabarcoding using group-specific primer sets in five freshwater fish species belonging to two taxonomic groups from a total of 94 water samples collected from western Japan. As a result, three-step data screening based on the DNA copy number of each haplotype detected successfully eliminated suspected false positive haplotypes. Furthermore, eDNA analysis could almost perfectly reconstruct the phylogenetic and phylogeographic patterns obtained for all target species with the conventional method. Despite existing limitations and future challenges, eDNA-based phylogeography can significantly reduce survey time and effort and is applicable for simultaneous analysis of multiple species in single water samples. eDNA-based phylogeography has the potential to revolutionize phylogeography.

X-ray crystallographic and mutational analysis of the NylC precursor: catalytic mechanism of autocleavage and substrate hydrolysis of nylon hydrolase.

Nylon hydrolase (NylC), a member of the N-terminal nucleophile (Ntn) hydrolase superfamily, is responsible for the degradation of various aliphatic nylons, including nylon-6 and nylon-66. NylC is initially expressed as an inactive precursor (36 kDa), but the precursor is autocatalytically cleaved at Asn266/Thr267 to generate an active enzyme composed of 27 and 9 kDa subunits. We isolated various mutants with amino acid changes at the catalytic centre. X-ray crystallographic analysis revealed that the NylC precursor forms a doughnut-shaped quaternary structure composed of four monomers (molecules A-D) with D2 symmetry. Catalytic residues in the precursor are covered by loop regions at the A/B interface (equivalent to the C/D interface). However, the catalytic residues are exposed to the solvent environment through autocleavage followed by movements of the loop regions. T267A, D306A and D308A mutations resulted in a complete loss of autocleavage. By contrast, in the T267S mutant, autocleavage proceeded slowly at a constant reaction rate (k = 2.8 × 10-5  s-1 ) until complete conversion, but the reaction was inhibited by K189A and N219A mutations. Based on the crystallographic and molecular dynamic simulation analyses, we concluded that the Asp308-Asp306-Thr267 triad, resembling the Glu-Ser-Ser triad conserved in Ntn-hydrolase family enzymes, is responsible for autocleavage and that hydrogen-bonding networks connecting Thr267 with Lys189 and Asn219 are required for increasing the nucleophilicity of Thr267-OH in both the water accessible and water inaccessible systems. Furthermore, we determined that NylC employs the Asp308-Asp306-Thr267 triad as catalytic residues for substrate hydrolysis, but the reaction requires Lys189 and Tyr146 as additional catalytic/substrate-binding residues specific for nylon hydrolysis.

Excimer laser coronary angioplasty versus manual aspiration thrombectomy in patients with ST-segment elevation myocardial infarction: analyzed by nuclear scintigraphy.

Clinical outcomes concerning the efficacy of excimer laser coronary angioplasty (ELCA) in real-world cases of acute myocardial infarction (MI) are limited. We evaluated and compared the impact of ELCA with manual aspiration thrombectomy on myocardial salvage and left ventricular (LV) systolic/diastolic function in patients with ST-segment elevation MI (STEMI) using nuclear scintigraphy.  We enrolled 143 consecutive patients with STEMI treated with ELCA (63 patients) or manual aspiration thrombectomy (80 patients) between September 2016 and December 2020 in a single-center hospital. We evaluated the peak creatine kinase (CK)/ creatine kinase-myocardial band (CK-MB) levels and performed single-photon emission computed tomography (SPECT) analyses with Quantitative Gated SPECT and Quantitative Perfusion SPECT (Auto QUANT 7.2) at 3-10 days using 123I-BMIPP and 3 months following percutaneous coronary intervention using 99mTc-tetrofosmin to evaluate myocardial salvage and LV systolic/diastolic function. No significant difference was observed in the patient and periprocedural characteristics. Peak CK-MB level was significantly different between the groups (ELCA group, 190.0 [70.5-342.0] IU/L vs. aspiration group, 256.5 [157.0-354.8] IU/L, p = 0.047). Although no significant difference was observed in myocardial salvage, significant improvement in the LV ejection fraction (14.1 [6.2-19.8]% vs. 9.5 [3.9-15.3]%, respectively, p = 0.018) and peak emptying rate (-0.54 [-1.02- (-0.27)] mL/s vs. -0.38 [-0.76- (-0.05)] mL/s, respectively, p = 0.017) were detected. ELCA could suppress the myocardial deviation enzymes and potentially improve systolic function compared to manual aspiration thrombectomy in patients with STEMI.

Structural Insights into the Very Low Activity of the Homocoenzyme B12 Adenosylmethylcobalamin in Coenzyme B12 -Dependent Diol Dehydratase and Ethanolamine Ammonia-Lyase.

The X-ray structures of coenzyme B12 (AdoCbl)-dependent eliminating isomerases complexed with adenosylmethylcobalamin (AdoMeCbl) have been determined. As judged from geometries, the Co-C bond in diol dehydratase (DD) is not activated even in the presence of substrate. In ethanolamine ammonia-lyase (EAL), the bond is elongated in the absence of substrate; in the presence of substrate, the complex likely exists in both pre- and post-homolysis states. The impacts of incorporating an extra CH2 group are different in the two enzymes: the DD active site is flexible, and AdoMeCbl binding causes large conformational changes that make DD unable to adopt the catalytic state, whereas the EAL active site is rigid, and AdoMeCbl binding does not induce significant conformational changes. Such flexibility and rigidity of the active sites might reflect the tightness of adenine binding. The structures provide good insights into the basis of the very low activity of AdoMeCbl in these enzymes.

High Internal Atrial Defibrillation Threshold Is Related to a High Risk of Recurrence After Catheter Ablation for Long-Standing Persistent Atrial Fibrillation But Not for Persistent Atrial Fibrillation.

BACKGROUND: The atrial defibrillation threshold (ADFT) for internal cardioversion is theoretically related to the critical mass for sustaining atrial fibrillation (AF). OBJECTIVE: This study aimed to investigate the association of ADFT for internal cardioversion with the outcome of catheter ablation for non-paroxysmal AF (non-PAF). METHODS: We included 368 consecutive patients who underwent first-time catheter ablation for non-PAF. Based on the degree of ADFT recorded by the internal cardioversion before pulmonary vein isolation, we divided the patients into low ADFT (<20 J) and high ADFT (≥20 J) groups and analysed the association between ADFT and atrial tachyarrhythmia recurrence. RESULTS: There were 234 and 134 patients in the low and high ADFT groups, respectively. Of these, 39 patients (16.7%) and 41 (30.6%) patients, respectively, had atrial tachyarrhythmia recurrence during the 2.6±1.0 year follow-up. The high ADFT group showed a significantly higher atrial tachyarrhythmia recurrence than the low ADFT group (p=0.002). This finding was also noted in patients with long-standing persistent AF (p=0.032) but not in patients with persistent AF (p=0.159). The significant predictors of arrhythmia recurrence on multivariate analysis were high ADFT (p=0.004) and long-standing persistent AF (p=0.011). In multivariate analysis within the long-standing persistent AF group, only ADFT remained a significant risk factor for AF recurrence (p=0.035). CONCLUSIONS: The high ADFT of internal cardioversion was found to be a risk factor for post-catheter ablation recurrence in patients with long-standing persistent AF but not in those with persistent AF.

Incidence and predictors of frailty progression among octogenarians with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention.

BACKGROUND: Frailty is one of the most serious health problems in older individuals with cardiovascular disease. Moreover, frailty progression is associated with subsequent adverse outcomes; therefore, the prevention of frailty progression is an important clinical issue. However, the incidence and predictors of frailty progression following acute myocardial infarction have not yet been fully elucidated. METHODS: The present study is a sub-analysis of an observational multicenter registry retrospectively evaluating clinical outcomes of 288 octogenarians who underwent primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI) between January 2014 and December 2016 at five hospitals. We identified 244 patients who survived until discharge and evaluated frailty at baseline and discharge using the Clinical Frailty Scale (CFS). We defined frailty progression as an increase of at least one level in the CFS score at discharge from baseline and assessed the predictors of frailty progression. RESULTS: Frailty progression was observed in 29.5% of patients. Patients with frailty progression were older, had more severe conditions with a higher prevalence of Killip 4 status and mechanical circulatory support use, more frequently experienced in-hospital events such as stroke (4/72, 6% vs. 0/172, 0%, p = 0.007), and had longer hospital stays than those without frailty progression [19 (11-35) vs. 13 (9-19) days, p<0.01]. Multivariate analysis showed that age (odds ratio 1.08, 95% confidence interval 1.00-1.17, p = 0.046) and Killip 4 status at baseline (odds ratio 3.34, 95% confidence interval 1.26-8.85, p = 0.01) were significant predictors of frailty progression. CONCLUSIONS: In-hospital frailty progression was commonly observed in octogenarians with STEMI who underwent primary PCI and survived until discharge, and was associated with more severe clinical conditions.

Reactivating chaperones for coenzyme B12-dependent diol and glycerol dehydratases and ethanolamine ammonia-lyase.

Adenosylcobalamin (AdoCbl) or coenzyme B12-dependent enzymes tend to undergo mechanism-based inactivation during catalysis or inactivation in the absence of substrate. Such inactivation may be inevitable because they use a highly reactive radical for catalysis, and side reactions of radical intermediates result in the damage of the coenzyme. How do living organisms address such inactivation when enzymes are inactivated by undesirable side reactions? We discovered reactivating factors for radical B12 eliminases. They function as releasing factors for damaged cofactor(s) from enzymes and thus mediate their exchange for intact AdoCbl. Since multiple turnovers and chaperone functions were demonstrated, they were renamed "reactivases" or "reactivating chaperones." They play an essential role in coenzyme recycling as part of the activity-maintaining systems for B12 enzymes. In this chapter, we describe our investigations on reactivating chaperones, including their discovery, gene cloning, preparation, characterization, activity assays, and mechanistic studies, that have been conducted using a wide range of biochemical and structural methods that we have developed.