Studies in the past have clearly established that CTLA4 is a susceptible gene for Graves' disease (GD). However, association studies between CTLA4 and the risk of developing Graves' ophthalmopathy (GO) in GD patients have shown conflicting results. In this study, associations of five CTLA4 single nucleotide polymorphisms (-1722A/G, -1661A/G, -318C/T, +49G/A, CT60) with GD risk and GO susceptibility in GD patients were investigated in a Chinese population. Our results showed that either +49A/G or CT60 polymorphism was associated with GD susceptibility in the Chinese population. Significant differences in the distribution of the genotypes or alleles evaluated between GD patients with and without clinically evident GO were only found for -318C/T polymorphism (P = 0.03). Multiple logistic regressions revealed that the -318T allele was negatively associated with GO under both additive and dominant genetic models (adjusted OR = 0.56, 95%CI 0.35-0.89, P = 0.014; adjusted OR = 0.51, 95%CI 0.30-0.84, P = 0.009, respectively). Stratification analysis according to gender demonstrated different scenarios concerning the role of the -318T allele in GO risk: a significant protective role for GO was only confirmed in male but not in female GD patients. Haplotype analyses showed that only the haplotypes containing the -318T allele played a protective role in GO. In conclusion, results from this study suggested that the -318T allele might play a protective role in GO susceptibility for GD patients at least in the Chinese population. However, extended analyses with larger sample size should be carried out in patients from different ethnic origins to further verify this association.

An engine isolation system via tuneable damping mounts can contribute to enhanced automobile performance. In this study, a magnetorheological fluids (MRF) mount in squeeze mode for engine isolation is proposed and its damping characteristics are analysed. Based on an engine isolation dynamic model with three degrees of freedom, a hierarchical fuzzy control (HFC) system is proposed to decrease the vertical vibration force and roll moment transmitted from an engine to a foundation. On the control level, a fuzzy controller is designed to isolate the engine vertical vibration. On the coordination level, fuzzy reasoning is adopted to realize a coordination strategy for tuning the damping of each MRF mount in order to minimize the transmitted torque. The simulation is developed in MATLAB, and the experimental isolation system for an actual engine is built in the laboratory. With wide excitation frequency inputs under different operation conditions, studies on different engine mount isolation systems are carried out. Simulation results indicate that MRF mounts using the HFC strategy have more advantages than passive elastomeric mounts or hydraulic mounts, especially in the low-frequency range. Laboratory results confirm that the engine HFC system via MRF mounts performs markedly better than the passive mount system. The absolute force transmissibility ratio and torque transmissibility ratio are reduced to lower than 0.3 in actual complex excitation, which is very significant for an improvement in noise, vibration, and harshness.

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