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According to the synaptic homeostasis hypothesis (SHY), sleep serves to renormalize synaptic connections that have been potentiated during the prior wake phase due to ongoing encoding of information. SHY focuses on glutamatergic synaptic strength and has been supported by numerous studies examining synaptic structure and function in neocortical and hippocampal networks. However, it is unknown whether synaptic down-regulation during sleep occurs in the hypothalamus, i.e., a pivotal center of homeostatic regulation of bodily functions including sleep itself. We show that sleep, in parallel with the synaptic down-regulation in neocortical networks, down-regulates the levels of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) in the hypothalamus of rats. Most robust decreases after sleep were observed at both sites for AMPARs containing the GluA1 subunit. Comparing the effects of selective rapid eye movement (REM) sleep and total sleep deprivation, we moreover provide experimental evidence that slow-wave sleep (SWS) is the driving force of the down-regulation of AMPARs in hypothalamus and neocortex, with no additional contributions of REM sleep or the circadian rhythm. SWS-dependent synaptic down-regulation was not linked to EEG slow-wave activity. However, spindle density during SWS predicted relatively increased GluA1 subunit levels in hypothalamic synapses, which is consistent with the role of spindles in the consolidation of memory. Our findings identify SWS as the main driver of the renormalization of synaptic strength during sleep and suggest that SWS-dependent synaptic renormalization is also implicated in homeostatic control processes in the hypothalamus. Sleep normalizes synaptic connections in the cortex and hippocampus that have been potentiated during the preceding wake phase. This study shows that slow-wave sleep also down-regulates AMPA receptor levels in the hypothalamus, a brain region that regulates sleep. [ABSTRACT FROM AUTHOR]

In this paper we show that there exist infinitely many square-free numbers of the form n 2 + n + 1 . We achieve this by deriving an asymptotic formula by improving the reminder term from previous results. [ABSTRACT FROM AUTHOR]

Common flow cytometry-based methods used for functional assessment of antigen-specific T cells rely on de novo expression of intracellular cytokines or cell surface activation induced markers. They come with some limitations such as complex experimental setting, loss of cell viability and often high unspecific background which impairs assay sensitivity. We have previously shown that staining of activated ß2-integrins either with multimers of their ligand ICAM-1 or with a monoclonal antibody can serve as a functional marker detectable on T cells after minutes (CD8+) or few hours (CD4+) of activation. Here, we present a simple method for detection of activated ß2-integrins in combination with established cell surface activation induced markers. We observed that activated ß2-integrins were still detectable after 14 hours of stimulation, allowing their detection together with CD137 and CD154. Combinatorial gating of cells expressing activated ß2-integrins and CD137 or CD154 reduced background in unstimulated samples, increasing the signal-to-noise ratio and allowing improved assessment of low-frequency T cell responses. Extracellular staining of these markers highly correlated with production of intracellular cytokines IL-2, TNF or IFNg in CD4+ and CD8+ T cells. As an exemplary application, SARS-CoV-2 spike-specific T cell responses were assessed in individuals after COVID-19 vaccination. This method should be useful for epitope discovery projects and for the simultaneous monitoring of lowfrequency antigen-specific CD4+ and CD8+ T cell responses in various physiological situations. [ABSTRACT FROM AUTHOR]

Conformational change of the β2 integrin lymphocyte function‐associated antigen 1 (LFA‐1) is an early marker of T cell activation. A protocol using the mAb clone m24 recognizing the active, extended high‐affinity conformation has been previously described for the assessment of functional CD4+ and CD8+ T cells in response to MHC‐peptide stimulation. We investigated the applicability of the m24 mAb to detect the activation of γδ T cells in response to different soluble and immobilized stimuli. m24 mAb staining was associated with the expression of cytokines and was detectable as early as 10 min after stimulation, but with different kinetics depending on the nature of the stimulus. Hence, we conclude that this assay is suitable for the detection of functional γδ T cells and allows the assessment of activation more rapidly than alternative methods such as cytokine detection. Intracellular staining, protein trafficking inhibitors, or prior knowledge of the stimulating moiety recognized are no longer required for monitoring γδ T cell activation. [ABSTRACT FROM AUTHOR]

In this paper, we show that for any fixed 1 < c < 967/805, every sufficiently large positive number N, and a small constant 휀 > 0, the Diophantine inequality p 1 c + p 2 c + p 3 c + p 4 c − N < ε has a solution in prime numbers p1, p2, p3, p4,such that p1 = x2 + y2 + 1. [ABSTRACT FROM AUTHOR]

We show that there exist infinitely many consecutive square-free numbers of the form n2 + 1, n2 + 2. We also establish an asymptotic formula for the number of such square-free pairs when n does not exceed given sufficiently large positive number. [ABSTRACT FROM AUTHOR]

Let ε > 0 be a small constant. We prove that whenever η is real and constants λi satisfy some necessary conditions, then there exist infinitely many prime triples p1, p2, p3 satisfying the inequality |λ1p1+λ2p2+λ3p3+η| < ε and such that p3 = x2 + y2 + 1. [ABSTRACT FROM AUTHOR]

Advanced laryngeal squamous cell carcinoma (LSCC) is the second most prevalent type of head and neck squamous cell carcinoma (HNSCC). Identifying microRNAs (miRNAs) related to key regulatory molecules or mechanisms could offer an alternative approach to developing new treatment strategies. The aim of our study is to evaluate significant correlations among deregulated miRNAs in advanced laryngeal carcinoma and to analyze, in silico, their strength of association, targets, and the most deregulated pathways. Several miRNAs demonstrated promising co-expression results, specifically miR-93-5p, miR-145-5p, and miR-210-3p. Their expressions were explored and further validated in a large set of in vivo advanced LSCC samples, which were subsequently used for bioinformatics and enrichment analyses. Our results highlight the significant roles of miR-93-5p, miR-145-5p, and miR-210-3p in regulating major pathways linked to the cell cycle via epithelial-to-mesenchymal transition (EMT), PI3K/Akt signaling, hypoxia, metabolism, apoptosis, angiogenesis, and metastasis. The associations between the expressions of these miRNAs and patients' clinical features could be central to the progression of advanced LSCC. Overall, our study provides important insights into the co-expression and regulatory networks of miR-93-5p, miR-145-5p, and miR-210-3p in advanced laryngeal carcinoma, underscoring their potential as therapeutic targets or biomarkers for this aggressive cancer. Further research is needed to elucidate the specific mechanisms through which these miRNAs contribute to the pathogenesis and progression of laryngeal carcinoma.

Common flow cytometry-based methods used for functional assessment of antigen-specific T cells rely on de novo expression of intracellular cytokines or cell surface activation induced markers. They come with some limitations such as complex experimental setting, loss of cell viability and often high unspecific background which impairs assay sensitivity. We have previously shown that staining of activated ß 2 -integrins either with multimers of their ligand ICAM-1 or with a monoclonal antibody can serve as a functional marker detectable on T cells after minutes (CD8 + ) or few hours (CD4 + ) of activation. Here, we present a simple method for detection of activated ß 2 -integrins in combination with established cell surface activation induced markers. We observed that activated ß 2 -integrins were still detectable after 14 hours of stimulation, allowing their detection together with CD137 and CD154. Combinatorial gating of cells expressing activated ß 2 -integrins and CD137 or CD154 reduced background in unstimulated samples, increasing the signal-to-noise ratio and allowing improved assessment of low-frequency T cell responses. Extracellular staining of these markers highly correlated with production of intracellular cytokines IL-2, TNF or IFNγ in CD4 + and CD8 + T cells. As an exemplary application, SARS-CoV-2 spike-specific T cell responses were assessed in individuals after COVID-19 vaccination. This method should be useful for epitope discovery projects and for the simultaneous monitoring of low-frequency antigen-specific CD4 + and CD8 + T cell responses in various physiological situations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Schöllhorn, Maia, Kimmerle, Born, Rammensee, Dimitrov and Gouttefangeas.)

Conformational change of the β2 integrin lymphocyte function-associated antigen 1 (LFA-1) is an early marker of T cell activation. A protocol using the mAb clone m24 recognizing the active, extended high-affinity conformation has been previously described for the assessment of functional CD4 + and CD8 + T cells in response to MHC-peptide stimulation. We investigated the applicability of the m24 mAb to detect the activation of γδ T cells in response to different soluble and immobilized stimuli. m24 mAb staining was associated with the expression of cytokines and was detectable as early as 10 min after stimulation, but with different kinetics depending on the nature of the stimulus. Hence, we conclude that this assay is suitable for the detection of functional γδ T cells and allows the assessment of activation more rapidly than alternative methods such as cytokine detection. Intracellular staining, protein trafficking inhibitors, or prior knowledge of the stimulating moiety recognized are no longer required for monitoring γδ T cell activation., (© 2022 The Authors. European Journal of Immunology published by Wiley-VCH GmbH.)