RESUMEN
BACKGROUND Leukocyte telomere length (LTL) is regarded as a potential marker of biological aging. Oxidative stress plays a major role in the rate of telomeric DNA loss. The aim of this study was to explore whether the LTL was shorter in Chinese patients with premature coronary artery disease (PCAD) than in non-CAD controls and to determine the relationship between oxidative stress and LTL shortening in this population. MATERIAL AND METHODS Patients for coronary angiography were recruited. In total, 128 patients with PCAD and 128 non-CAD controls were enrolled. Samples of circulating leukocytes and plasma were collected. The mean LTL was measured using a polymerase chain reaction-based assay and expressed as the ratio of telomere repeat copies to single-copy gene (SCG) copies (T/S ratio). Reactive oxygen species (ROS) levels and total antioxidant capacity (T-AOC) were determined in plasma. RESULTS Both the T/S ratio (0.88±0.86 vs. 1.10±0.57, P=0.015) and telomere base pairs (4.97±1.37 kb vs. 5.32±0.91 kb, P=0.015) were significantly shorter in the PCAD group than in non-CAD controls. The T-AOC levels of the PCAD group were significantly lower than those of the non-CAD controls (0.482 mM [0.279, 0.603 mM]) vs. 0.778 mM [0.421, 0.924 mM], P=0.000). The ratio of T-AOC to ROS in the PCAD patients was significantly decreased compared to that of the non-CAD controls (0.1026±0. 1587 [Mm*ml/ng] vs. 0.1435±0.1946 [Mm*ml/ng], P=0.013). CONCLUSIONS The results point to a potential link between reduced LTLs in patients with PCAD and early onset of atherosclerosis. The decline in antioxidant capacity may play an important role in accelerating the attrition of telomeres in PCAD patients.
Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Estrés Oxidativo/genética , Telómero/fisiología , Adulto , Anciano , Pueblo Asiatico/genética , Aterosclerosis/genética , Aterosclerosis/fisiopatología , Biomarcadores/sangre , China , Enfermedad de la Arteria Coronaria/fisiopatología , Femenino , Humanos , Leucocitos/fisiología , Masculino , Persona de Mediana Edad , Estrés Oxidativo/fisiología , Especies Reactivas de Oxígeno/sangre , Especies Reactivas de Oxígeno/metabolismo , Telómero/genética , Homeostasis del Telómero/genética , Homeostasis del Telómero/fisiologíaRESUMEN
Behavioral psychology is increasingly important in relationship marketing. As key factors of emotional interactions between buyer and seller, psychological contracts and opportunistic behaviors play a critical role in interorganizational relationships which are based on personal relationships of boundary spanners and top management. Most of the existing research mainly focus on positive performance of cooperation but ignoring the dark side of relationships. This study introduces the psychological contract into the exploration of why formal contracts cannot completely avoid opportunistic behaviors. It mainly investigates whether psychological contracts in relationships can reduce the occurrence of opportunistic behaviors. The results show that psychological contract has a significant positive effect on the relationship quality, and negatively affect opportunistic behavior through trust and commitment. The positive relationship between psychological contracts and relationship quality is moderated by dependence. This study enriches and expands the domestic and foreign research on psychological contracts and opportunistic behaviors in relationship marketing.