Architect i4000sr

Parameters of liver function, including ALT, AST, AFP, AFU, TBIL, ALB, GLO, and the white-to-sphere ratio (A/G), were measured by a Roche automatic biochemical analyzer (Roche Cobas c 701; Roche, Switzerland). The serum HBV-DNA load was quantitated using an automatic nucleic acid purification and fluorescence PCR analysis system (Anadas9850, Amplly, China). The levels of HBsAg, anti-HBs, HBeAg, and anti-HBe were tested using an automatic microparticle chemiluminescence immune analyzer (ARCHITECT i4000SR, Abbott, USA). HBsAg negativity was defined as < 50 IU/ml.

The serum CEA, CA19-9, Cyfra21-1, and carbohydrate antigen 72-4 (CA72-4) concentrations in CRC patients and healthy controls were measured by Architect I4000 SR (Abbott, Chicago, IL, United States ).

Vitamin A was detected in samples by Agilent1200 (Agilent Technologies Inc., Santa Clara, CA, USA) tools and Chromsystems (Chromsystems Instruments Chemicals GmbH, Gräfelfing, Germany) reagent through high-performance liquid chromatography with flame ionization detector methods.
Folate was detected in samples using ARCHITECT i4000Sr (Abbott Laboratories, Lake Bluff, IL, USA) and ARCHITECT Folate-only reagent with chemiluminescent microparticle immunoassay methods.

At the CML, all samples were re-analyzed by CMIA for HBsAg using ARCHITECT HBsAg (Abbott Laboratories, IL,USA) on ARCHITECT i4000SR platform according to the instructions of the manufacturer.
The samples were also analyzed with CMIA for anti-HBs and total anti-HBc using ARCHITECT anti-HBs and ARCHITECT anti-HBc II (Abbott Laboratories, IL, USA), respectively on the ARTCHITECT i4000SR machine following the manufacturer’s instructions. HBsAg positive samples were further analyzed for HBeAg and anti-HBe with the ARCHITECT HBeAg and ARCHITECT anti-HBe (Abbott Laboratories, IL, USA) assays. All HBsAg positive and isolated anti-HBc-positive samples were analyzed for antibodies against hepatitis delta virus (anti-HDV) with the ETI-AB-DELTA K-2 kits (Diasorin, Saluggia, Italy) according to the instructions by the manufacturer.

Blood samples were collected in the morning with overnight fast. Serum folate levels, our independent variable of interest, were measured through Chemiluminescent Microparticle Immunoassay (ARCHITECT i4000Sr; Abbott, Abbott Park, IL).
KNHANES measured HRQOL, our dependent variable of interest, using EQ-5D questionnaire. The elderly was surveyed on EQ-5D through face-to-face interviews. The EQ-5D consists of five dimensions (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression). Each dimension has three health status levels meaning no problem, some problem, and a severe problem. The EQ-5D score was derived by combining all scores for the five dimensions, which ranged from 0 to 1; 0 indicating death and 1 indicating perfect health state. The score less than 0 means health state worse than death. The EQ-5D score was estimated through N3 model [31 (link)].

Folate was detected in the samples using ARCHITECT i4000Sr (Abbott Laboratories, Abbott Park, IL, USA) and ARCHITECT Folate-only reagent with chemiluminescent microparticle immunoassay methods.
Hs-CRP was measured using Cobas immunoturbidimetry (Roche, Berlin, Germany).

Plasma samples were separated from the whole blood by centrifugation, and 150 μl of plasma was used to detect the HCV antibody by ARCHITECT i4000SR (Abbott, America). A value of S/CO <1 was considered non-reactive, while a value of S/CO ≥1 was considered reactive. The experiments were repeated twice. If both retests were non-reactive, the detection of HCV antibody was determined as negative, but if one or two retests were reactive, then it was considered positive. Six hundred fifty microliter centrifuged plasma was used to detect the presence of HCV RNA, detection was performed on a fully automated Roche COBAS AmpliPrep instrument, directly docked to the Roche COBAS TaqMan 96 Analyzer. All assay procedures were performed according to the manufacturer's protocols.