Computational Probing the Methylation Sites Related to EGFR Inhibitor-Responsive Genes

The emergence of drug resistance is one of the main obstacles to the treatment of lung cancer patients with EGFR inhibitors. Here, to further understand the mechanism of EGFR inhibitors in lung cancer and offer novel therapeutic targets for anti-EGFR-inhibitor resistance via the deep mining of pharmacogenomics data, we associated DNA methylation with drug sensitivities for uncovering the methylation sites related to EGFR inhibitor sensitivity genes. Specifically, we first introduced a grouped regularized regression model (Group Least Absolute Shrinkage and Selection Operator, group lasso) to detect the genes that were closely related to EGFR inhibitor effectiveness. Then, we applied the classical regression model (lasso) to identify the methylation sites associated with the above drug sensitivity genes. The new model was validated on the well-known cancer genomics resource: CTRP. GeneHancer and Encyclopedia of DNA Elements (ENCODE) database searches indicated that the predicted methylation sites related to EGFR inhibitor sensitivity genes were related to regulatory elements. Moreover, the correlation analysis on sensitivity genes and predicted methylation sites suggested that the methylation sites located in the promoter region were more correlated with the expression of EGFR inhibitor sensitivity genes than those located in the enhancer region and the TFBS. Meanwhile, we performed differential expression analysis of genes and predicted methylation sites and found that changes in the methylation level of some sites may affect the expression of the corresponding EGFR inhibitor-responsive genes. Therefore, we supposed that the effectiveness of EGFR inhibitors in lung cancer may be improved by methylation modification in their sensitivity genes.

Olfactory Functions Difference on Gas Station Workers Using Sniffin’ Sticks Test

ABSTRACT Background: Chronic exposure of volatile substances can cause the impaired olfactory function. Objective: To identify the difference of olfactory function at Gas Station workers in Medan city. Method: Cross-sectional analitic study. A total of 80 persons consisting of 40 gas station operators and 40 non-operators who fulfilled the inclusion criteria. The applied statistical analysis was Mann Whitney, Fisher's Exact, Chi Square, T independent, Spearman with 95% confidence level. Result: Proportion of the impaired olfactory function in the gas station operator group by 77.5% and non-operator group by 0%. Significant correlation was obtained between age, duration of work with the impaired olfactory function (p = 0,047, p = 0,001). The gas station operators will suffer the impaired olfactory function if they works for ≥ 3.89 years. Conclusion: There were differences of olfactory functions on the gas station workers by using Sniffin 'Sticks Test.

On the non-hypercyclicity of scalar type spectral operators and collections of their exponentials

Generalizing the case of a normal operator in a complex Hilbert space, we give a straightforward proof of the non-hypercyclicity of a scalar type spectral operator A in a complex Banach space as well as of the collection { e t A } t ≥ 0 {\{{e}^{tA}\}}_{t\ge 0} of its exponentials, which, under a certain condition on the spectrum of the operator A, coincides with the C 0 {C}_{0} -semigroup generated by A. The spectrum of A lying on the imaginary axis, we also show that non-hypercyclic is the strongly continuous group { e t A } t ∈ ℝ {\{{e}^{tA}\}}_{t\in {\mathbb{R}}} of bounded linear operators generated by A. From the general results, we infer that, in the complex Hilbert space L 2 ( ℝ ) {L}_{2}({\mathbb{R}}) , the anti-self-adjoint differentiation operator A ≔ d d x A:= \tfrac{\text{d}}{\text{d}x} with the domain D ( A ) ≔ W 2 1 ( ℝ ) D(A):= {W}_{2}^{1}({\mathbb{R}}) is non-hypercyclic and so is the left-translation strongly continuous unitary operator group generated by A.

The Difference of Olfactory Functions in The Workers of The Gas Station by Using Sniffin’ Stickstest in Medan City

Introduction: Chronic exposure of volatile substances can cause the impaired olfactory function. Objectives: In order to identify the difference of olfactory function in the workers of the Gas Station in Medan city. Methods: Analytical research with cross- sectional approach. The research subjects were 80 persons consisting of 40 gas station operators and 40 non-operators who fulfilled the inclusion and exclusion criteria. The applied statistical analysis was Mann Whitney, Fisher's Exact, Chi Square, T independent, Spearman with 95% confidence level. Results: Proportion of the impaired olfactory function in the gas station operator group by 77.5% and non-operator group by 0%. Significant correlation was obtained between age, duration of work with the impaired olfactory function (p = 0,047, p = 0,001). The gas station operators will suffer the impaired olfactory function if they work for  3.89 years. Conclusions: There were differences of olfactory functions in the gas station workers by using Sniffin 'Sticks Test in Medan city.

Monopoly Rents in Motorcycle Taxi Services in Bangkok, Thailand

This paper examines the market for motorcycle taxi services in Bangkok, Thailand, in terms of economic rent and the effects of such rent on fares. Three sources of monopoly rent in motorcycle taxi services are identified. Locational rent is attributed to the level of accessibility that is specific to the location of a motorcycle taxi stand. Such locations are limited in terms of accessibility, with few locations that can be substituted with another. The quota rent is arbitrarily created by rent-seeking activities, that is, by setting a quota on the number of operators in each location. Territorial rent is created by restricting the service area for each operator group. Depending on the behavior of the so-called influential people, the monopoly can be either enforced or eroded. A regression analysis of fare data provides evidence that supports the hypothesis of locational and territorial rents. Locational rent decreases as a motorcycle taxi stand is located farther away from a rail transit station. Motorcycle taxi groups with demarcated territories command a fare premium, which may indicate territorial rent. Some stands enjoy a degree of monopoly where there are limited substitute feeder transport modes; stands located near bus stops also command a fare premium because of accessibility. This situation implies that bus services do not compete with motorcycle taxis but provide complementary services. The additional economic rent created by new transit systems is unfairly captured by operator groups and influential people. It is suggested that a competitive market be created for motorcycle taxi services, with value-capture measures that are intended to create a more efficient and fairer feeder transport system.