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Purpose: Background noise and voice problems among teachers can degrade listening conditions in classrooms. The aim of this literature review is to understand how these acoustic degradations affect spoken language processing in 6- to 18-year-old children. Method: In a narrative report and meta-analysis, we systematically review studies that examined the effects of noise and/or impaired voice on children's response accuracy and response time (RT) in listening tasks. We propose the Speech Processing under Acoustic DEgradations (SPADE) framework to classify relevant findings according to three processing dimensions--speech perception, listening comprehension, and auditory working memory--and highlight potential moderators. Results: Thirty-one studies are included in this systematic review. Our meta-analysis shows that noise can impede children's accuracy in listening tasks across all processing dimensions (Cohen's d between -0.67 and -2.65, depending on signal-to-noise ratio) and that impaired voice lowers children's accuracy in listening comprehension tasks (d = -0.35). A handful of studies assessed RT, but results are inconclusive. The impact of noise and impaired voice can be moderated by listener, task, environmental, and exposure factors. The interaction between noise and impaired voice remains underinvestigated. Conclusions: Overall, this review suggests that children have more trouble perceiving speech, processing verbal messages, and recalling verbal information when listening to speech in noise or to a speaker with dysphonia. Impoverished speech input could impede pupils' motivation and academic performance at school.

This study measured the impact of articulation exercises using a cork and articulation exercises for lip spreading on the formant frequencies of vowels and listener perceptions of femininity in transgender women. Thirteen transgender women were recorded before and after the cork exercise and before and after the lip spreading exercise. Speech samples included continuous speech during reading and were analyzed using Praat software. Vowel formant frequencies (F1, F2, F3, F4, F5) and vowel space were determined. A listening experiment was organized using naïve cisgender women and cisgender men rating audio samples of continuous speech. Masculinity/femininity, vocal quality and age were rated, using a visual analogue scale (VAS). Concerning vowel formant frequencies, F2 /a/ and F5 /u/ significantly increased after the lip spreading exercise, as well as F3 /a/, F3 /u/ and F4 /a/ after the cork exercise. The lip spreading exercise had more impact on the F2 /a/ than the cork exercise. Vowel space did not change after the exercises. The fundamental frequency (f o) increased simultaneously during both exercises. Both articulation exercises were associated with significantly increased listener perceptions of femininity of the voice. Subtle changes in formant frequencies can be observed after performing articulation exercises, but not in every formant frequency or vowel. Cisgender listeners rated the speech of the transgender women more feminine after the exercises. Further research with a more extensive therapy program and listening experiment is needed to examine these preliminary findings. [ABSTRACT FROM AUTHOR]

In their environment, cells must cope with mechanical stresses constantly. Among these, nanoscale deformations of plasma membrane induced by substrate nanotopography are now largely accepted as a biophysical stimulus influencing cell behavior and function. However, the mechanotransduction cascades involved and their precise molecular effects on cellular physiology are still poorly understood. Here, using homemade fluorescent nanostructured cell culture surfaces, we explored the role of Bin/Amphiphysin/Rvs (BAR) domain proteins as mechanosensors of plasma membrane geometry. Our data reveal that distinct subsets of BAR proteins bind to plasma membrane deformations in a membrane curvature radius-dependent manner. Furthermore, we show that membrane curvature promotes the formation of dynamic actin structures mediated by the Rho GTPase CDC42, the F-BAR protein CIP4, and the presence of PI(4,5)P 2 . In addition, these actin-enriched nanodomains can serve as platforms to regulate receptor signaling as they appear to contain interferon-γ receptor (IFNγ-R) and to lead to the partial inhibition of IFNγ-induced JAK/STAT signaling.

The GDT1 family is broadly spread and highly conserved among living organisms. GDT1 members have functions in key processes like glycosylation in humans and yeasts and photosynthesis in plants. These functions are mediated by their ability to transport ions. While transport of Ca 2+ or Mn 2+ is well established for several GDT1 members, their transport mechanism is poorly understood. Here, we demonstrate that H + ions are transported in exchange for Ca 2+ and Mn 2+ cations by the Golgi-localized yeast Gdt1 protein. We performed direct transport measurement across a biological membrane by expressing Gdt1p in Lactococcus lactis bacterial cells and by recording either the extracellular pH or the intracellular pH during the application of Ca 2+ , Mn 2+ or H + gradients. Besides, in vivo cytosolic and Golgi pH measurements were performed in Saccharomyces cerevisiae with genetically encoded pH probes targeted to those subcellular compartments. These data point out that the flow of H + ions carried by Gdt1p could be reversed according to the physiological conditions. Together, our experiments unravel the influence of the relative concentration gradients for Gdt1p-mediated H + transport and pave the way to decipher the regulatory mechanisms driving the activity of GDT1 orthologs in various biological contexts., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Recent advances in the field demonstrate the high diversity and complexity of endocytic pathways. In the current study, we focus on the endocytosis of L1CAM. This glycoprotein plays a major role in the development of the nervous system, and is involved in cancer development and is associated with metastases and poor prognosis. Two L1CAM isoforms are subject to endocytosis: isoform 1, described as a clathrin-mediated cargo; isoform 2, whose endocytosis has never been studied. Deciphering the molecular machinery of isoform 2 internalisation should contribute to a better understanding of its pathophysiological role. First, we demonstrated in our cellular context that both isoforms of L1CAM are mainly a clathrin-independent cargo, which was not expected for isoform 1. Second, the mechanism of L1CAM endocytosis is specifically mediated by the N-BAR domain protein endophilin-A3. Third, we discovered PSTPIP1, an F-BAR domain protein, as a novel actor in this endocytic process. Finally, we identified galectins as endocytic partners and negative regulators of L1CAM endocytosis. In summary, the interplay of the BAR proteins endophilin-A3 and PSTPIP1, and galectins fine tune the clathrin-independent endocytosis of L1CAM., (© 2023 The Authors. Traffic published by John Wiley & Sons Ltd.)

Endocytic mechanisms actively regulate plasma membrane composition and sustain fundamental cellular functions. Recently, we identified a clathrin-independent endocytic (CIE) modality mediated by the BAR domain protein endophilin-A3 (endoA3, encoded by SH3GL3), which controls the cell surface homeostasis of the tumor marker CD166 (also known as ALCAM). Deciphering the molecular machinery of endoA3-dependent CIE should therefore contribute to a better understanding of its pathophysiological role, which remains so far unknown. Here, we investigate the role of actin, Rho GTPases and microtubules, which are major players in CIE processes, in this mechanism. We show that the actin cytoskeleton is dynamically associated with endoA3- and CD166-positive endocytic carriers, and that its perturbation strongly inhibits the process of CD166 uptake. We also reveal that the Rho GTPase Rac1, but not Cdc42, is a master regulator of this endocytic route. Finally, we provide evidence that microtubules and kinesin molecular motors are required to potentiate endoA3-dependent endocytosis. Of note, our study also highlights potential compensation phenomena between endoA3-dependent CIE and macropinocytosis. Altogether, our data deepen our understanding of this CIE modality and further differentiate it from other unconventional endocytic mechanisms. This article has an associated First Person interview with the first author of the paper., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)

Competence for DNA transformation is a major strategy for bacterial adaptation and survival. Yet, this successful tactic is energy-consuming, shifts dramatically the metabolism, and transitory impairs the regular cell-cycle. In streptococci, complex regulatory pathways control competence deactivation to narrow its development to a sharp window of time, a process known as competence shut-off. Although characterized in streptococci whose competence is activated by the ComCDE signaling pathway, it remains unclear for those controlled by the ComRS system. In this work, we investigate competence shut-off in the major human gut commensal Streptococcus salivarius. Using a deterministic mathematical model of the ComRS system, we predicted a negative player under the control of the central regulator ComX as involved in ComS/XIP pheromone degradation through a negative feedback loop. The individual inactivation of peptidase genes belonging to the ComX regulon allowed the identification of PepF as an essential oligoendopeptidase in S. salivarius. By combining conditional mutants, transcriptional analyses, and biochemical characterization of pheromone degradation, we validated the reciprocal role of PepF and XIP in ComRS shut-off. Notably, engineering cleavage site residues generated ultra-resistant peptides producing high and long-lasting competence activation. Altogether, this study reveals a proteolytic shut-off mechanism of competence in the salivarius group and suggests that this mechanism could be shared by other ComRS-containing streptococci., Competing Interests: The authors of this manuscript have the following competing interests: PH is a Research Director at FNRS.