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Genetic factors are known to be important in the development of esophageal squamous cell carcinoma (ESCC). Epidermal growth factor (EGF) can activate several signaling pathways leading to proliferation, differentiation, and tumorigenesis of epithelial tissues by binding with its receptor. Interindividual variations in EGF production were genetically contributed to EGF +61 G/A polymorphism. The purpose of this study is to investigate the potential association between EGF gene polymorphism and ESCC in a Chinese population. In this study, we analyzed single nucleotide polymorphism of EGF +61 G/A in 158 patients with ESCC and 212 age- and sex-matched controls in a Chinese population using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) strategy and DNA sequencing. The variant genotypes of GA/AA were associated with a significantly decreased risk of ESCC compared with the wild-type homozygote GG (OR = 0.657, 95% CI: 0.434-0.996). However, no significant difference was observed between the EGF +61 G/A polymorphism and the risk of ESCC when the analyses were stratified in terms of age, gender, smoking status, different clinical stage, and lymph node status. The EGF +61 G/A polymorphism is associated with ESCC in a Chinese population. Our data suggests that the EGF gene may play a role in the development of ESCC. [ABSTRACT FROM AUTHOR]

In this paper, we study the relaxation time of a bistable system driven by correlated noises when there are two different kinds of time delays in the deterministic (τ) and random (θ) forces, respectively. The expression for the relaxation time Tc is derived by the projection operator method, in which the effects of the memory kernels are taken into account. After introducing a dimensionless parameter R (R = D/α, where D is the strength of multiplicative noise and α is the strength of additive noise), and then performing numerical computations, we find the following: (1) for the case of R ≤ 1, the relaxation time Tc increases as τ increases, i.e. τ slows down the fluctuation decay of the dynamical variable for the case of R ≤ 1; (2) however, for the case of R > 1, Tc decreases as τ increases, i.e. τ enhances the fluctuation decay of the dynamical variable for the case of R > 1; (3) Tc decreases as θ increases, i.e. θ enhances the fluctuation decay of the dynamical variable for the three cases of R (R > 1, R=1, and R < 1). [ABSTRACT FROM AUTHOR]

NaOH-based hydrolysis of epoxypropyltrimethylammonium chloride (ETA) was carried out in a batch reactor using ethanol/water system. The analytic technique, headspace-gas chromatography, was employed in order to follow the time evolution of ETA aqueous solution. Various effects on hydrolysis degree, such as, molar ratio of ethanol/water, NaOH concentration, reaction temperature, and dosage of hydrolysis product (2,3-dihydroxypropyl trimethylammonium chloride) were investigated. And then the kinetic model of the hydrolysis of ETA was developed and the possible mechanism of nucleophilic ring opening reaction was proposed. Furthermore, the model parameters of the process were also determined by data fitting. The results show that ETA hydrolysis follows the pseudo-first order law and kinetic model agrees well with the experimental results. Therefore, based on this kinetic model we could control the hydrolysis degree of ETA during ETA-involved cationic etherification of natural polymer in order to improve the etherification efficiency. [ABSTRACT FROM AUTHOR]