Measurement of biochemical markers
Peripheral venous blood samples were collected after 15 minutes of rest
into tubes containing ethylenediaminetetraacetic acid (EDTA). Troponin-I
levels were measured by chemiluminescent immunoassay using an Immulite
2500 device (Siemens Medical Solutions, Erlangen, Germany). MCP-1 and
SP-A levels were measured by enzyme-linked immunosorbent assay
(Elabscience human ELISA kit, UK).