Neither P‐gp SNP variants, P‐gp expression nor functional P‐gp activity predicts MDR in a preliminary study of plasma cell myeloma

Abstract

Background: The objective of this work was to obtain a controlled subjective and objective in vivo clinical comparison of the Passy‐Muir, Shiley, and Ball speaking valves. Methods: Ten patients free of laryngeal pathology but dependent on tracheotomy for respiration were tested with each of the speaking valves. Olfaction was assessed for each patient using the University of Pennsylvania Smell Identification Test (UPSIT). Acoustic and perceptual analyses included subjective assessments, noninstrumental objective assessments (including maximum phonation time, and S:Z ratio), and instrumental objective assessments (including fundamental frequency:maximum phonation range, vocal intensity, perturbation, naturalness, and turbulence). Oxygen saturation was assessed by pulse oximetry. Results: There was a highly significant statistical difference in olfaction and speech naturalness, in favor of the Ball valve (The Airway Company, Forest Hill, MD). The Ball valve's speech parameters were generally better than with the Passy‐Muir and Shiley valves, including maximum phonation, S:Z ratio, jitter, noise, and turbulence, although the differences were not statistically significant. There were no differences among the valves in oxygen saturation levels. Conclusion: This study illustrates that olfaction and certain speech parameters, most noticeably speech naturalness, are significantly improved with the Ball valve as compared to the Passy‐Muir and Shiley valves. © 2012 ARS–AAOA, LLC.

Drug targets and resistance mechanisms in multiple myeloma

“…A SNP variant in the ABCB1 gene was associated with a twofold higher risk for MM [145] . In contrast, another study did not find a correlation between P-gp activities or expression and MM subgroups [146] . Regarding BTZ-resistance, the putative role of the multidrug efflux transporter MDR1/P-glycoprotein expression has been investigated, however, its contribution to acquired BTZ-resistance remains unclear [147] .…”

Selected Genetic Polymorphisms Associated with Hypoxia and Multidrug Resistance in Monoclonal Gammopathies Patients

“…Moreover, patients and control groups did not differ regard ing MDR1 haplotype distribution (rs1045642, rs2032582 and rs1128503), and their results do not support major influence of MDR1 variants on the risk of MM in Caucasians. Thus, functional importance of SNPs in MDR1 is controversial as the association between a polymorphism (rs1045642) in MDR1 and effect of treatment showed contradictory results so far [56][57][58][59][60][61].…”