With an aging population, the incidence of obstructive sleep apnea syndrome (OSAS) is rising, resulting in a growing number of patients undergoing surgery who are also affected by OSAS. The combined impact of anesthetic drugs and OSAS-related neurological damage has drawn significant attention. Here, wild-type (WT) and Tau-knockout (Tau-KO) mice were subjected to intermittent hypoxia and sevoflurane exposure to induce OSAS and sevoflurane-induced neurotoxicity. Protein expression of tau phosphorylation (Tau-Ser202/Thr205 and Tau-Ser422) was measured by Western blotting. Immunofluorescence was used to visualize tau phosphorylation (Tau-Ser202/Thr205) in the hippocampal CA1 region. Mitochondrial function was evaluated by measuring reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and ATP levels. Cognitive functions were assessed using the Morris water maze and Y-maze tests. We found that compared to the WT OSAS group, sevoflurane significantly increased tau phosphorylation and mitochondrial dysfunction in WT OSAS mice, leading to cognitive impairment. Interestingly, idebenone treatment mitigated sevoflurane-induced mitochondrial dysfunction and cognitive impairment in WT OSAS mice, but it did not affect tau phosphorylation. Compared to the Tau-KO control group, Tau-KO OSAS mice exhibited mitochondrial dysfunction and cognitive impairment, but sevoflurane did not exacerbate mitochondrial dysfunction or cognitive impairment in these mice. These findings suggest that sevoflurane exacerbates cognitive impairments in OSAS mice through tau phosphorylation-induced mitochondrial dysfunction, but also uncovered differing mechanisms between cognitive impairments induced by OSAS and those exacerbated by sevoflurane.

This study aims to investigate whether androgen deprivation, simulating conditions of aging or disease-induced low testosterone levels, increases the susceptibility of male mice to sevoflurane neurotoxicity, and whether testosterone supplementation can reverse the toxic effects of sevoflurane. In here, young male mice were subjected to orchiectomy (ORC) to induce testosterone deprivation. Various techniques, including western blotting, immunofluorescence, Morris Water Maze, Golgi staining, and neuronal signal measurement, were used to evaluate the effects of sevoflurane on long-term (ORC 10 weeks) and short-term (ORC 2 weeks) testosterone deprivation, and assess whether testosterone (1 mg/kg 1 h before sevoflurane exposure) could mitigate sevoflurane-induced neurotoxicity. Flutamide and anastrozole were administered to study testosterone's pathways of action. We found that sevoflurane increased tau phosphorylation and decreased the transient amplitude of Ca2+ signals and dendritic spine density in dorsal hippocampal CA1 (dCA1) neurons, leading to cognitive impairment in testosterone-deprived male mice. Testosterone treatment reversed the effects of sevoflurane in short-term testosterone-deprived male mice, but not in long-term testosterone-deprived male mice. Additionally, the neuroprotective effect of testosterone was blocked by flutamide rather than anastrozole. We have discovered for the first time that testosterone can mitigate the sevoflurane-induced neurotoxicity in testosterone-deprived male mice and that there exists a therapeutic time window, which may be mediated by androgen receptors. This may provide new insights into the neuroprotective role of sex hormones.

Sleep fragmentation (SF) is a common sleep problem experienced during the perioperative period by older adults, and is associated with postoperative cognitive dysfunction (POCD). Increasing evidence indicates that delta-wave activity during non-rapid eye movement (NREM) sleep is involved in sleep-dependent memory consolidation and that hippocampal theta oscillations are related to spatial exploratory memory. Recovery sleep (RS), a self-regulated state of sleep homeostasis, enhances delta-wave power and memory performance in sleep-deprived older mice. However, it remains unclear whether RS therapy has a positive effect on cognitive changes following SF in older mouse models. Therefore, this study aimed to explore whether preoperative RS can alleviate cognitive deficits in aged mice with SF. A model of preoperative 24-h SF combined with exploratory laparotomy-induced POCD was established in 18-month-old mice. Aged mice were treated with preoperative 6-h RS following SF and postoperative 6-h RS following surgery, respectively. The changes in hippocampus-dependent cognitive function were investigated using behavioral tests, electroencephalography (EEG), local field potential (LFP), magnetic resonance imaging, and neuromorphology. Mice that underwent 24-h SF combined with surgery exhibited severe spatial memory impairment; impaired cognitive performance could be alleviated by preoperative RS treatment. In addition, preoperative RS increased NREM sleep; enhanced EEG delta-wave activity and LFP theta oscillation in the hippocampal CA1; and improved hippocampal perfusion, microstructural integrity, and neuronal damage. Taken together, these results provide evidence that preoperative RS may ameliorate the severity of POCD aggravated by SF by enhancing delta slow-wave activity and hippocampal theta oscillation, and by ameliorating the reduction in regional cerebral blood flow and white matter microstructure integrity in the hippocampus.

Introduction: Current electroencephalogram (EEG) indices for monitoring the depth of anaesthesia have not been adjusted for age. This study aims to identify the most suitable EEG indices for monitoring anaesthesia depth across different age groups. Method: In here, we conducted a prospective observational trial to observe whether different EEG features in different age groups can detect anaesthesia depth and compare their performance. Results: In Group 1, absolute θ had the highest prediction probability (Pk) value (0.78 ± 0.07), while relative γ had the lowest relative coefficient of variation (CV) value in states 1 (0.160), 2 (0.153), 3 (0.214) and 4 (0.144). In Group 2, absolute θ had the highest Pk value (0.81 ± 0.09), and relative γ had the lowest CV value in states 1 (0.159), 2 (0.178), 3 (0.140) and 4 (0.095). In Group 3, absolute δ had the highest Pk value (0.79 ± 0.08), with absolute slow wave having the lowest CV value in States 1 (0.196), 2 (0.258), 3 (0.295) and 4 (0.181). In Group 4, absolute δ had the highest Pk value (0.75 ± 0.10), and absolute slow wave had the lowest CV value in States 1 (0.176), 2 (0.192), 3 (0.185) and 4 (0.144). Conclusion: In this study, we found that absolute θ and relative γ are the most suitable choices for young and middle-aged patients, while absolute δ and absolute slow wave are the most suitable choices for young elderly and elderly patients.

Objective Breast cancer (BC) is a deadly form of malignancy responsible for the death of a large number of women every year. Cuproptosis is a newly discovered form of cell death that may have implications for the prognosis of BC. Long non‐coding RNAs (lncRNAs) have been shown to be involved in the progression and development of BC. Here within, a novel model capable of predicting the prognosis of patients with BC was established based on cuproptosis-related lncRNAs. Methods Data of breast cancer patients was downloaded, including clinical information from The Cancer Genome Atlas (TCGA) database and lncRNAs related to cuproptosis were isolated. In total, nine lncRNAs related to copper death were obtained by Cox regression model based on Least Absolute Shrinkage and Selector Operation (LASSO) algorithm for model construction. The model was verified by overall survival (OS), progression-free survival (PFS) and receiver operating characteristic (ROC) curve. The differences in immune function, tumor mutation burden (TMB) and tumor immune dysfunction and exclusion (TIDE) between patients with different risk scores were analyzed. Results Based on cuproptosis-related lncRNAs, a prognostic model for predicting BC was constructed. Each patient was assigned a risk score based on our model formula. We found that patients with higher risk scores had significantly lower OS and PFS, increased TMB, and higher sensitivity to immunotherapy. Conclusions The model established in this study based on cuproptosis-related lncRNAs may be capable of improving the OS of patients with BC.

BACKGROUND:Patients undergoing surgical anesthesia increasingly suffer from preoperative depression. Clinical studies have shown that depression is a risk factor for perioperative neurocognitive disorders (PNDs) in elder patients. However, the underlying mechanism, especially at the neural circuit level, remains poorly understood.METHODS:Right carotid artery separation under sevoflurane and chronic social defeat stress (CSDS) in adult mice were used to establish surgical anesthesia and chronic depression models. Cognitive function was assessed by the Y maze and novel object recognition tests. A chemogenetic approach was used to modulate the locus coeruleus-dorsal hippocampal CA1 (LC-dCA1) circuit. Hippocampal synaptic alterations were evaluated by Golgi staining and whole-cell patch clamp recording.RESULTS:We found that CSDS induced synaptic impairments in dorsal hippocampal CA1 pyramidal neurons and cognitive deficits in adult mice after surgery under sevoflurane. Chemogenetic activation of the LC-dCA1 pathway significantly alleviated the CSDS-induced synaptic impairments and cognitive dysfunction. On the contrary, inhibition of this pathway could mimic CSDS-induced deficits. Furthermore, we showed that dopamine played an important role in CSDS-induced PNDs in adult mice after surgery/sevoflurane.CONCLUSION:Overall, our results have demonstrated a vital role for the LC-dCA1 pathway in CSDS-induced PNDs in adult mice undergoing surgery with sevoflurane anesthesia.

ABSTRACT:Ischemic postconditioning (I/Post) reduces I/R injury by activating endogenous cardioprotection mechanisms, such as the JAK/signal transducer and activator of transcription 3 (STAT3) and PI3K/Akt pathways, which offer a traditional approach to myocardial protection. According to a previous study, cardioprotection by I/Post may be lost in aged mice, and in our previous research, hypoxic postconditioning (H/Post) lacked a protective effect in senescent cardiomyocytes, which was associated with low expression of long noncoding RNA H19. The N6-methyladenosine (m 6 A) modification is a dynamic and reversible process that has been confirmed to play a role in cardiovascular diseases. However, the mechanisms of m 6 A modification in myocardial I/Post remain to be explored. Neonatal cardiomyocytes were isolated from 2-day-old Sprague-Dawley rats, and senescence was induced by d -galactose, followed by stimulation of hypoxia-reoxygenation and H/Post. Hypoxic injury was evaluated by cell viability and the Bcl-2/Bax protein ratio. Total m 6 A levels were measured using a colorimetric m 6 A RNA Methylation Quantification Kit, and the m 6 A modified and differentially expressed mRNA was determined by MeRIP (methylated RNA immunoprecipitation). We found that H/Post increased m 6 A methylation and decreased RNA mA demethylase alkB homolog 5 (ALKBH5) expression in aged cardiomyocytes. Furthermore, ALKBH5 knockdown exacerbated injury following H/Post in senescent cardiomyocytes. In addition, ALKBH5 regulated STAT3 expression by mediating its m 6 A modification and long noncoding RNA H19/miR-124-3p. ALKBH5 also alleviated the H/Post injury induced by the low expression of STAT3 in senescent cardiomyocytes.

The profiles of acid phosphatase isoenzymes of several well defined species of the genus Leishmania were compared. The profiles were generated after isoelectric focusing of parasite extracts in polyacrylamide and incubation of the gels with an appropriate substrate coupled to an azo dye. Analysis of the zymograms showed that there is species-specificity of the acid phosphatase isoenzyme maps in Leishmania. It was also demonstrated that different strains of the same species present identical pattern of enzyme activity. The method even enabled the differentiation of closely related species which were previously difficult to identify. Some technical aspects of the isoelectric focusing procedure are discussed. The method described here can be used as an aid for species identification of Leishmania.

Objective The monitoring of anesthetic depth based on electroencephalogram (EEG) derivation is not currently adjusted for age. Here we analyze the influence of age factors on EEG characteristics. Methods Frontal EEG recordings were obtained from 80 adults during routine clinical anesthesia. The characteristics of EEG with age and anesthesia were observed during four kinds of anesthesia. Results Relative slow wave power, relative delta power, absolute slow wave power, BIS value and approximate entropy were statistically different in the adjacent anesthesia states (P < 0.05). Under very deep anesthesia, the relative slow wave power increases linearly with age (R2 = 0.1802; P = 0.0001), the relative delta power decreased linearly with age (R2 = 0.3587; P < 0.0001), the BIS value increased linearly with age (R2 = 0.0986; P = 0.005), and the approximate entropy increases linearly with age (R2 = 0.0565; P = 0.036). The relative slow wave power did not change in an age-dependent manner. Conclusions When using relative delta power, absolute slow wave power, BIS value and approximate entropy to monitor the depth of anesthesia, the influence of age should be considered, However, when using relative slow wave power, age should not be considered.