Generalized chain surgeries and applications

We describe the Stein handlebody diagrams of Milnor fibers of Brieskorn singularities $x^p + y^q + z^r = 0$. We also study the natural symplectic operation by exchanging two Stein fillings of the canonical contact structure on the links in the case $p = q = r$, where one of the fillings comes from the minimal resolution and the other is the Milnor fiber. We give two different interpretations of this operation, one as a symplectic sum and the other as a monodromy substitution in a Lefschetz fibration

Antifungal screening and in silico mechanistic studies of an in-house azole library

Systemic Candida infections pose a serious public health problem with high morbidity and mortality. C. albicans is the major pathogen identified in candidiasis, however non-albicans Candida spp. with antifungal resistance are now more prevalent. Azoles are first-choice antifungal drugs for candidiasis, however they are ineffective for certain infections caused by the resistant strains. Azoles block ergosterol synthesis by inhibiting fungal CYP51, which leads to disruption of fungal membrane permeability. In this study, we screened for antifungal activity of an in-house azole library of 65 compounds to identify hit matter followed by a molecular modelling study for their CYP51 inhibition mechanism. Antifungal susceptibility tests against standard Candida spp. including C. albicans revealed derivatives 12 and 13 as highly active. Furthermore, they showed potent antibiofilm activity as well as neglectable cytotoxicity in a mouse fibroblast assay. According to molecular docking studies 12 and 13 have the necessary binding characteristics for effective inhibition of CYP51. Finally, molecular dynamics (MD) simulations of the C. albicans CYP51 (CACYP51) homology model's catalytic site complexed with 13 was stable demonstrating excellent binding. This article is protected by copyright. All rights reserved

Dephasing Times in a Non-degenerate Two-Dimensional Electron Gas

Studies of weak localization by scattering from vapor atoms for electrons on a liquid helium surface are reported. There are three contributions to the dephasing time. Dephasing by the motion of vapor atoms perpendicular to the surface is studied by varying the holding field to change the characteristic width of the electron layer at the surface. A change in vapor density alters the quasi-elastic scattering length and the dephasing due to the motion of atoms both perpendicular and parallel to the surface. Dephasing due to the electron-electron interaction is dependent on the electron density.Comment: 4 pages, Revte

Magnetoresistance of nondegenerate quantum electron channels formed on the surface of superfluid helium

Transport properties of quasi-one-dimensional nondegenerate quantum wires formed on the surface of liquid helium in the presence of a normal magnetic field are studied using the momentum balance equation method and the memory function formalism. The interaction with both kinds of scatterers available (vapor atoms and capillary wave quanta) is considered. We show that unlike classical wires, quantum nondegenerate channels exhibit strong magnetoresistance which increases with lowering the temperature.Comment: 8 pages, 7 figure

Epilobium hirsutum alters xenobiotic metabolizing CYP1A1, CYP2E1, NQO1 and GPx activities, mRNA and protein levels in rats

Context: Natural products have attracted increasing interests due to their use in flavoring, nutrition, cosmetics, pharmacy and medicine. Epilobium hirsutum L. (Onagraceae) is known for its analgesic, antimicrobial, and antiproliferative activity. CYP1A1 and CYP2E1, xenobiotic metabolizing enzymes, serve as a metabolic activation route yielding reactive metabolites that are eliminated by the action of NQO1 and glutathione peroxidase (GPx) enzymes. Objective: This study investigated in vivo effects of Epilobium hirsutum (EH) on CYP2E1, CYP1A1, NQO1 and GPx activities, protein and mRNA expressions in liver. Materials and methods: Male Wistar Albino rats were injected with EH at a dose of 37.5mg/kg i.p. daily for 9d. CYP2E1, CYP1A1, NQO1 and GPx activities, protein and mRNA levels were determined by enzyme assays, Western blotting and qPCR, respectively. Results: CYP1A1 associated ethoxyresorufin-O-deethylase activity of control and EH-treated animals were found as 6.54±1.21 and 4.48±1.67nmol/min/mg, respectively. CYP2E1 associated aniline 4-hydroxylase of control and EH group were 0.537±0.011 and 0.109±0.01nmol/min/mg, respectively. However, EH treatment increased the GPx and NQO1 activities from 0.069±0.015 to 0.107±0.026nmol/min/mg and from 163.34±92 to 588.3±14nmol/min/mg, respectively. Furthermore, protein and mRNA expression analysis revealed that CYP1A1 and CYP2E1 levels were decreased while those of NQO1 and GPx increased after EH treatment. Discussion and conclusion: Our current data suggest that the metabolism of xenobiotics, including drugs, may be altered due to changes in the expression and activity of these proteins by EH. © 2013 Informa Healthcare USA, Inc

Cross-cultural Adaptation and Validation of Beliefs about Medicines Questionnaire on Asthma and Chronic Obstructive Pulmonary Disease Patients

OBJECTIVES: Inadequate adaptation to long-term treatment of chronic illnesses is the most common reason for the inability to obtain the benefits medications can provide. Treatment compliance is influenced by several factors. Beliefs about Medicines Questionnaire (BMQ) developed by Horne et al. in 1999 to evaluate the cognitive representation of medicines have many validation studies, which resulted in good psychometric properties. The aim of the present study was to evaluate the reliability and validity of the BMQ Turkish translation in patients with asthma and chronic obstructive pulmonary disease (COPD). MATERIAL AND METHODS: Fifty asthma and 50 COPD patients participated in this methodological study. The scale was adapted to Turkish through translation, comparison with other language versions, back translation, and a pre-test. The structural validity was assessed using factor analysis. RESULTS: Similar to the original scale, factor analysis confirmed that BMQ had a four-factor structure that accounts for 58.23% of the total variance. The BMQ showed an acceptable internal consistency (Cronbach's alpha coefficient: specific-necessity, 0.832: specific-concerns, 0.722; general-harm, 0.792; and general-overuse, 0.682). The factor analysis revealed the same patterns for all questions between the Turkish and original scales. CONCLUSION: The psychometric properties of the BMQ were consistent with those reported in the original study. We found that the Turkish translation of BMQ is a valid and reliable tool for assessing medicine-related beliefs in patients with asthma and COPD