ABSTRACT
Background: The significance of implicit self-schema and other-schema in major depressive disorder (MDD) is highlighted by both cognitive theory and attachment theory. The purpose of the current study was to investigate the behavioral and event-related potential (ERP) characteristics of implicit schemas in MDD patients. Methods: The current study recruited 40 patients with MDD and 33 healthy controls (HCs). The participants were screened for mental disorders using the Mini-International Neuropsychiatric Interview. Hamilton Depression Rating Scale-17 and Hamilton Anxiety Rating Scale-14 were employed to assess the clinical symptoms. Extrinsic Affective Simon Task (EAST) was conducted to measure the characteristics of implicit schemas. Meanwhile, reaction time and electroencephalogram data were recorded. Results: Behavioral indexes showed that HCs responded faster to positive self and positive others than negative self (t = -3.304, p = 0.002, Cohen's d = 0.575) and negative others (t = -3.155, p = 0.003, Cohen's d = 0.549), respectively. However, MDD did not show this pattern (p > 0.05). The difference in other-EAST effect between HCs and MDD was significant (t = 2.937, p = 0.004, Cohen's d = 0.691). The ERP indicators of self-schema showed that under the condition of positive self, the mean amplitude of LPP in MDD was significantly smaller than that in HCs (t = -2.180, p = 0.034, Cohen's d = 0.902). The ERP indexes of other-schema showed that HCs had a larger absolute value of N200 peak amplitude for negative others (t = 2.950, p = 0.005, Cohen's d = 0.584) and a larger P300 peak amplitude for positive others (t = 2.185, p = 0.033, Cohen's d = 0.433). The above patterns were not shown in MDD (p > 0.05). The comparison between groups found that under the condition of negative others, the absolute value of N200 peak amplitude in HCs was larger than that in MDD (t = 2.833, p = 0.006, Cohen's d = 1.404); under the condition of positive others, the P300 peak amplitude (t = -2.906, p = 0.005, Cohen's d = 1.602) and LPP amplitude (t = -2.367, p = 0.022, Cohen's d = 1.100) in MDD were smaller than that in HCs. Conclusion: Patients with MDD lack positive self-schema and positive other-schema. Implicit other-schema might be related to abnormalities in both the early automatic processing stage and the late elaborate processing stage, while the implicit self-schema might be related only to the abnormality in the late elaborate processing stage.
ABSTRACT
Gout is the most common autoinflammatory arthritis characterized by elevated serum urate and recurrent attacks of intra-articular crystal deposition of monosodium urate (MSU) in tissues. The pathogenesis of gout has not been fully determined, although certain genetic factors are involved in the development of gout. Accumulated data suggested that MSU crystal-induced inflammation is a paradigm of innate immunity. As Toll-like receptors (TLRs) are the underlying mechanisms of the innate immune response, the present study aimed to investigate whether TLR2 polymorphisms are associated with gout. Two single-nucleotide polymorphisms (Arg677Trp and Arg753Gln, rs5743708) in TLR2 were genotyped by polymerase chain reaction-restriction fragment length polymorphism and the -196 to -174 del polymorphism was investigated using the allele-specific polymerase chain reaction in 431 individuals (215 patients with gout and 216 healthy controls). TLR2 Arg677Trp and Arg753Gln genotyping indicated that all the positive samples were of the wild-type genotype. No significant differences in genotype (χ2=1.686, P=0.430) and allele (χ2=1.430, P=0.232) frequencies of the -196 to -174 del polymorphism between the patients with gout and the control groups was observed. Our results suggested that the TLR2 Arg677Trp, Arg753Gln and the -196 to -174 del polymorphisms were not associated with susceptibility to primary gouty arthritis.
