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PubblicazioneImmature olfactory sensory neurons are intrinsically excitable and show maturation-dependent changes in voltage-gated Na+ and K+ currents( 2026)Olfactory sensory neurons (OSNs) detect odorants and send electrical signals to glomeruli in the olfactory bulb. Unlike most neurons, OSNs are continuously regenerated throughout life and immature neurons contribute to odorant-evoked responses in glomeruli. However, their intrinsic excitability properties are largely unknown. Here, we used acute slices of the olfactory epithelium from neonatal OMP-GFP mice to visually identify mature and immature OSNs and performed patch-clamp recordings to investigate their functional properties. Loose-patch recordings showed that immature OSNs display spontaneous firing at lower frequency than mature neurons. Whole-cell recordings showed that immature OSNs have more depolarized resting potentials, higher input resistance, fire only with phasic patterns, and generate slower action potentials with more depolarized thresholds. Instead, mature OSNs exhibited both phasic and tonic repetitive firing and faster spike kinetics. Voltage-clamp experiments showed that voltage-gated Na+ currents in immature OSNs were almost entirely TTX-sensitive, whereas mature OSNs had both TTX-sensitive and TTX-resistant components whose availability depends on membrane potential. Voltage-gated K+ currents also differed with maturation: immature OSNs lacked a transient component and had only a sustained K+ current, whereas mature OSNs displayed both a transient component and an increased sustained current. Analysis of single-cell transcriptomic data identified upregulation of some Na+ and K+ channel genes during OSN maturation, consistent with the functional changes. Together, these results provide insights into the intrinsic excitability of immature OSNs and show how intrinsic properties change as OSNs mature, providing a foundation for future studies on the role of immature OSNs in sensory processing.
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PubblicazioneBeyond night vision: the expanding role of rod photoreceptors in bright light( 2026)According to the standard view, most species including humans possess a “duplex retina”, with a rod system dedicated to low light (night) vision and a cone system dedicated to daylight vision. This separation of photon detection into a rod and cone regime is attributed to the low sensitivity of cones in dim light and saturation of rods in brighter light. However, mounting evidence gained from in vitro and in vivo studies in several species have demonstrated that specific mechanisms enable rod photoreceptors to significantly contribute to vision in bright and even very bright light. In this review we aim to elaborate on this revised framework for the duplex retina, and we propose rods should be considered to be tuned to “low contrast” rather than to “low ambient luminance”. Importantly, saturation of rod photoreceptors at higher light levels has been an assumption in research studies as well as clinical tests, and consideration of an updated role of rod photoreceptors may warrant reinterpretation of past and future results.
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PubblicazioneEffects of smoking cessation on taste function in heavy smokers undergoing hemiglossectomy for tongue squamous cell carcinoma( 2025)Purpose: Smokers with squamous cell carcinoma (SCC) of the tongue may be particularly prone to experience multifactorial gustatory dysfunction. This study investigates the effects of heavy smoking on taste perception in patients undergoing glossectomy type IIIa (i.e. non-compartment hemiglossectomy) for SCC of the tongue. Methods: Gustatory function was assessed in 30 heavy-smoking patients with SCC of the tongue using a validated taste strips test. Psychophysical evaluations were conducted at baseline and at 3, 6, 9, and 12 months post-surgery. Results: At baseline, mean taste strip scores (TSS [SD]) were significantly lower in patients compared to controls (8.7 [1.9] vs. 11.6 [2.1], P <.001). Post-treatment, TSS in patients declined to 7.2 [1.0] at 3 months, followed by a gradual recovery to 7.6 [2.3] at 6 months, 8.4 [2.8] at nine months, and 8.9 [3.9] at 12 months. Patients who quit smoking achieved significant recovery, with TSS improving from 7.4 [0.9] at three months to 11.8 [1.4] at twelve months, nearing control values. In contrast, smokers experienced a progressive decline, from 6.8 [1.2] at three months to 4.6 [1.6] at twelve months (P <.001). Adjuvant radiotherapy exacerbated short-term deficits (TSS of 6.6 [1.0] vs. 7.5 [0.9], P =.027 at three months) but showed no significant long-term impact. Conclusion: Persistent smoking worsens taste perception and impedes recovery in patients undergoing glossectomy type IIIa for tongue SCC. Smoking cessation significantly enhances sensory restoration, underscoring its importance in post-treatment care.
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PubblicazioneUnified Synthetic Ricci Curvature Lower Bounds for Riemannian and Sub-Riemannian Structures( 2026)Recent advances in the theory of metric measures spaces on the one hand, and of sub-Riemannian ones on the other hand, suggest the possibility of a "great unification" of Riemannian and sub-Riemannian geometries in a comprehensive framework of synthetic Ricci curvature lower bounds, as put forth in Villani (2019). With the aim of achieving such a unification program, in this paper we initiate the study of gauge metric measure spaces.
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PubblicazioneMaking PLUMED Fly: A Tutorial on Optimizing Performance( 2026)PLUMED is an open-source software package that is widely used for analyzing and enhancing molecular dynamics simulations that works in conjunction with most available molecular dynamics softwares. While the computational cost of PLUMED calculations is typically negligible compared to the molecular dynamics code’s force evaluation, the software is increasingly being employed to determine complex descriptors that are more computationally demanding. For these applications performance optimization becomes critical. In this tutorial, we describe a recently implemented tool that can be used to reliably measure code performance. We then use this tool to generate detailed performance benchmarks that show how calculations of large-numbers of distances, angles or torsions can be optimized by using vector-based commands rather than individual scalar operations. We then present benchmarks that illustrate how to optimize calculations of atomic order parameters and secondary structure variables. Throughout the tutorial and in our implementations we endeavor to explain the algorithmic tricks that are being used to optimize the calculations. We hope this allows others to understand these prescriptions and deploy them in their own calculations.