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Background: Obstructive sleep apnoea (OSA) is a sleep-disordered breathing characterized by intermittent hypoxia (IH) that may cause cognitive dysfunction. However, the impact of IH on molecular processes involved in cognitive function remains unclear. Methods: C57BL / 6 J mice were exposed to either normoxia (control) or IH for 6 weeks. DNA hydroxymethylation was quantified by hydroxymethylated DNA immunoprecipitation (hMeDIP) sequencing. ten-eleven translocation 1 (Tet1) was knocked down by lentivirus. Specifically, cognitive function was assessed by behavioral experiments, pathological features were assessed by HE staining, the hippocampal DNA hydroxymethylation was examined by DNA dot blot and immunohistochemical staining, while the Wnt signaling pathway and its downstream effects were studied using qRT-PCR, immunofluorescence staining, and Luminex liquid suspension chip analysis. Results: IH mice showed pathological changes and cognitive dysfunction in the hippocampus. Compared with the control group, IH mice exhibited global DNA hydroxylmethylation in the hippocampus, and the expression of three hydroxylmethylases increased significantly. The Wnt signaling pathway was activated, and the mRNA and 5hmC levels of Wnt3a, Ccnd2, and Prickle2 were significantly up-regulated. Further caused downstream neurogenesis abnormalities and neuroinflammatory activation, manifested as increased expression of IBA1 (a marker of microglia), GFAP (a marker of astrocytes), and DCX (a marker of immature neurons), as well as a range of inflammatory cytokines (e.g. TNFa, IL3, IL9, and IL17A). After Tet1 knocked down, the above indicators return to normal. Conclusion: Activation of Wnt signaling pathway by hippocampal Tet1 is associated with cognitive dysfunction induced by IH. [ABSTRACT FROM AUTHOR]

Simple Summary: The incidence of obstructive sleep apnea in children is increasing year by year, and its occurrence and related metabolic and endocrine lesions may be related to hypothalamic dysfunction. Lysine acetylation is a common post-translational modification that is essential for metabolism. The aim of this study was to determine the effects of chronic intermittent hypoxia-induced lysine acetylation on hypothalamic function in an infant mice model, simulating pediatric obstructive sleep apnoea patients. Our study revealed the lysine acetylome and proteomic profile of the hypothalamus induced by chronic intermittent hypoxia in juvenile mice. Differentially acetylated proteins were involved in endocrine metabolism, the citrate cycle (TCA cycle), synapse function, and circadian entrainment. Our findings suggest that chronic intermittent hypoxia may induce metabolic and endocrine dysregulation through modulation of hypothalamic lysine acetylation. Paediatric obstructive sleep apnoea (OSA) is a highly prevalent sleep disorder resulting in chronic intermittent hypoxia (CIH) that has been linked to metabolism and endocrine impairment. Protein acetylation, which is a frequently occurring posttranslational modification, plays pivotal roles in the regulation of hypothalamic processes. However, the effects of CIH-induced global protein acetylation on hypothalamic function and endocrine metabolism remain poorly understood. To bridge this knowledge gap, we conducted a study utilizing liquid chromatography–mass spectrometry to analyse the lysine acetylome and proteome of the hypothalamus in healthy infantile mice exposed to 3 weeks of intermittent hypoxia (as a CIH model) compared to normoxic mice (as controls). Our analysis identified and quantified 2699 Kac sites in 2453 proteins. These acetylated proteins exhibited disruptions primarily in endocrine metabolism, the citrate cycle (TCA cycle), synapse function, and circadian entrainment. Additionally, we observed significant down-regulation of proteins that are known to be involved in endocrine hormone secretion. This study aimed to elucidate the molecular mechanisms underlying CIH-induced alterations in protein acetylation within the hypothalamus. By providing valuable insights into the pathophysiological processes associated with CIH and their impacts on hypothalamic function, our findings contribute to a deeper understanding of the consequences stemming from CIH-induced changes in protein acetylation within the hypothalamus as well as its potential role in endocrine impairment. [ABSTRACT FROM AUTHOR]

Radio frequency (RF) heating has been studied to inactivate bacteria in some powder foods. In this study, a 6 kW, 27.12 MHz RF system was used to pasteurize Salmonella in black fungus (Auricularia auricula) powder. The effects of different conditions (initial aw, electrodes gaps, particle sizes) on RF heating rate and uniformity were investigated. The results showed that RF heating rate was significantly (p < 0.05) improved with decreasing electrodes gap and increasing initial aw, and the heating rate was the slowest when the particle size was 120–160 mesh. However, these factors had no significant (p > 0.05) influence on heating uniformity. RF pasteurization of Salmonella in black fungus powder was also studied. The results showed that, to inactivate Salmonella for 5 log reductions in the cold spot (the center of surface layer), the time needed and bacteria heat resistance at designated temperature (65, 75, 85 °C) decreased with increasing aw, and the first order kinetics and Weibull model could be used to fit inactivation curves of Salmonella with well goodness. Quality analysis results showed that although RF pasteurization had no significant (p > 0.05) effect on Auricularia auricula polysaccharide (AAP) and total polyphenols, obvious changes were found on color. Results suggested that RF pasteurization can be considered as an effective pasteurization method for black fungus powder. [ABSTRACT FROM AUTHOR]

Background: High‐speed T2‐corrected multiecho MRS (HISTO‐MRS) is emerging as a quantitative modality for detecting muscle fat infiltration (MFF). However, the predictive value of HISTO‐MRS for the loss of ambulation (LoA) in Duchenne muscular dystrophy (DMD) is unknown. Purpose: To determine the feasibility of HISTO‐MRS for assessing MFF in DMD and further identify the predictive value of HISTO‐MRS for the LoA. Study Type: Prospective. Subjects: A total of 134 DMD boys (9.20 ± 2.43 years old) and 21 healthy boys (9.25 ± 2.10 years old). Field Strength/Sequence: A 3 T, fast spin echo T1‐weighted imaging (T1WI), two‐point‐Dixon gradient echo sequence (2‐pt‐Dixon) and HISTO‐MRS. Assessment: Subjective T1WI fat grades by three radiologists, ROI analysis for MFF on 2 pt‐Dixon (Dixon MFF) and MFF on HISTO‐MRS (HISTO MFF) by two radiologists. Clinical motor function: North Star Ambulatory Assessment, 10‐m run/walk time, Gowers maneuver, and time to four‐stairs climb and descend. Statistical Tests: Spearman rank correlation was used to assess the relation of fat filtration assessments and motor ability. Bland–Altman plots was performed to determine the agreement of HISTO MFF and Dixon MFF. Receiver operating characteristic (ROC) curves were analyzed to determine the discriminating ability of above MRI modalities for ambulatory and nonambulatory DMD. Logistic regression was used to identify the predictor of LoA. Variables with P < 0.05 in univariate logistic regression analysis were entered into the multivariate logistic regression model. Results: HISTO MFF was significantly correlated with Dixon MFF. Bland–Altman plots show good agreement of HISTO MFF and Dixon MFF. ROC curves indicated that HISTO MFF show similar discrimination of LoA for DMD with Dixon MFF but better value than T1WI fat grades. Logistic regression showed that HISTO MFF was an independent predictor for LoA. Data Conclusion: HISTO‐MRS is a potential quantitative method for assessing fat infiltration and shows predictive value for LoA in DMD patients. Level of Evidence: 1. Technical Efficacy: Stage 5. [ABSTRACT FROM AUTHOR]