Labospect 006

Laboratory evaluations of plasma lipid and apolipoprotein levels were performed within two days before PCI. Commercial reagent kits (Determiner L TC II, Determiner L LDL-C II, Determiner L HDL-C II, and Determiner L TG II; Kyowa Medex, Tokyo, Japan) were used to analyze plasma TC, LDL-C, HDL-C, and triglyceride (TG) levels, and lipid concentrations were measured using an automated chemical analyzer (Labospect 006, Hitachi, Tokyo, Japan). Apo-B and Apo-A1 were measured by immunonephelometry, and high-sensitivity C-reactive protein (hs-CRP) levels were measured by nephelometry. Apolipoprotein levels were measured at a central clinical laboratory (SRL, Inc., Tokyo, Japan).

Blood sampling was performed on the day of admission in hospitalized patients and throughout the clinical course in patients with severe disease. Total protein (TP), albumin, AST, lactate dehydrogenase (LDH), creatinine, and C-reactive protein (CRP) were measured by an Aqua-auto Kainos TP-II test, Aqua-auto Kainos ALB (Kainos, Tokyo, Japan), LaboFit AST, CicaFit LD-IFCC (Kanto Chemical Co., Inc., Tokyo, Japan), Signasu-auto CRE (Shino-test, Tokyo, Japan), and CRP-Latex X2 (Denka, Niigata, Japan), respectively, using a LABOSPECT006 (Hitachi High-Tech Co., Tokyo, Japan). PCT and ferritin were measured by Elecsys^® BRAHMS PCT and Elecsys^® Ferritin (Roche Diagnostics K.K., Tokyo, Japan), respectively, using a Cobas 8000 e602 (Roche Diagnostics K.K., Tokyo, Japan). The WBC count, hemoglobin (Hb), total neutrophil count, and total lymphocyte count were measured using a fully automatic blood cell counter XN-3000 (Sysmex Co., Kobe, Japan). HbA1c was measured using an Adams Hybrid AH 8280 (Arkray Factory, Shiga, Japan). The prothrombin time (PT), activated partial thromboplastin time (APTT), and D-dimer level were measured by a Thromborel S, Thrombocheck APTT-SLA, and LIASAUTO D-dimer Neo (Sysmex Co., Kobe, Japan), respectively, using an automatic coagulation analyzer CS-5100 (Sysmex Co., Kobe, Japan).

Precise plasma BHB levels were measured with LABOSPECT 006 (Hitachi, Ltd, Tokyo, Japan) using the Wako Autokit 3‐HB (FUJIFILM Wako Diagnostics, Lexington, MA, USA), which has high sensitivity and high specificity as it uses cyclic enzymatic reactions, according to the manufacturer’s standard protocol. Precise plasma glucose levels were measured with LABOSPECT 006 using the Aqua‐auto Kainos GLU (Kainos Laboratories Inc, Tokyo, Japan).

Laboratory evaluations of plasma lipid and apo levels were conducted within 2 days before PCI. Commercial reagent kits (Determiner L TC II, L LDL-C II, L HDL-C II, and L TG II; Kyowa Medex, Tokyo, Japan) were used to analyze total plasma cholesterol, LDL-C, HDL-C, and TG levels. Lipid concentrations were measured using an automated biochemical analyzer (Labospect 006; Hitachi, Tokyo, Japan). Apo-C3 was measured in chylomicron-free samples, and apo-B and a were measured using immunonephelometry. High-sensitivity C-reactive protein levels were measured using nephelometry. Apo levels were measured at a central clinical biochemistry laboratory (SRL Inc., Tokyo, Japan).

Each participant was present at the laboratory on the morning of the sampling day after fasting for 8–12 h. Each participant rested in a seated position prior to sampling. Blood sampling was performed by experienced laboratory technicians. Venous blood was collected into 5 mL serum separator tubes (Venoject II; Terumo, Tokyo, Japan) and 2 mL EDTA tubes (Venoject II; Terumo, Tokyo, Japan). EDTA samples immediately and serum tubes after 30 min in an upright position. All collection tubes were centrifuged at 3000× g for 10 min. Blood cell counts and hemoglobin A1c from EDTA samples were measured with an automated analyzer (Celltac G; Nihon Kohden, Tokyo, Japan). Levels of triglycerides, high-density lipoprotein cholesterol, total cholesterol, and uric acid were measured from serum using an automated analyzer (LABOSPECT006; Hitachi High-Tech Co., Tokyo, Japan). Systolic blood pressure and diastolic blood pressure were measured with the participants in the supine position. Height and body weight were measured with the participants wearing lightweight clothing. Global cognitive function was assessed by the Mini-Mental State Examination. The mean intima-media thickness of the common carotid artery was measured as an index of arteriosclerosis by sonography (Logiq 5; GE Healthcare, Little Chalfont, UK).