γCaMKII shuttles Ca²âº/CaM to the nucleus to trigger CREB phosphorylation and gene expression.

Activity-dependent CREB phosphorylation and gene expression are critical for long-term neuronal plasticity. Local signaling at CaV1 channels triggers these events, but how information is relayed onward to the nucleus remains unclear. Here, we report a mechanism that mediates long-distance communication within cells: a shuttle that transports Ca(2+)/calmodulin from the surface membrane to the nucleus. We show that the shuttle protein is γCaMKII, its phosphorylation at Thr287 by ßCaMKII protects the Ca(2+)/CaM signal, and CaN triggers its nuclear translocation. Both ßCaMKII and CaN act in close proximity to CaV1 channels, supporting their dominance, whereas γCaMKII operates as a carrier, not as a kinase. Upon arrival within the nucleus, Ca(2+)/CaM activates CaMKK and its substrate CaMKIV, the CREB kinase. This mechanism resolves long-standing puzzles about CaM/CaMK-dependent signaling to the nucleus. The significance of the mechanism is emphasized by dysregulation of CaV1, γCaMKII, ßCaMKII, and CaN in multiple neuropsychiatric disorders.

Sustained antidepressant effect of ketamine through NMDAR trapping in the LHb.

Ketamine, an N-methyl-D-aspartate receptor (NMDAR) antagonist1, has revolutionized the treatment of depression because of its potent, rapid and sustained antidepressant effects2-4. Although the elimination half-life of ketamine is only 13 min in mice5, its antidepressant activities can last for at least 24 h6-9. This large discrepancy poses an interesting basic biological question and has strong clinical implications. Here we demonstrate that after a single systemic injection, ketamine continues to suppress burst firing and block NMDARs in the lateral habenula (LHb) for up to 24 h. This long inhibition of NMDARs is not due to endocytosis but depends on the use-dependent trapping of ketamine in NMDARs. The rate of untrapping is regulated by neural activity. Harnessing the dynamic equilibrium of ketamine-NMDAR interactions by activating the LHb and opening local NMDARs at different plasma ketamine concentrations, we were able to either shorten or prolong the antidepressant effects of ketamine in vivo. These results provide new insights into the causal mechanisms of the sustained antidepressant effects of ketamine. The ability to modulate the duration of ketamine action based on the biophysical properties of ketamine-NMDAR interactions opens up new opportunities for the therapeutic use of ketamine.

Excitation-transcription coupling, neuronal gene expression and synaptic plasticity.

Excitation-transcription coupling (E-TC) links synaptic and cellular activity to nuclear gene transcription. It is generally accepted that E-TC makes a crucial contribution to learning and memory through its role in underpinning long-lasting synaptic enhancement in late-phase long-term potentiation and has more recently been linked to late-phase long-term depression: both processes require de novo gene transcription, mRNA translation and protein synthesis. E-TC begins with the activation of glutamate-gated N-methyl-D-aspartate-type receptors and voltage-gated L-type Ca2+ channels at the membrane and culminates in the activation of transcription factors in the nucleus. These receptors and ion channels mediate E-TC through mechanisms that include long-range signalling from the synapse to the nucleus and local interactions within dendritic spines, among other possibilities. Growing experimental evidence links these E-TC mechanisms to late-phase long-term potentiation and learning and memory. These advances in our understanding of the molecular mechanisms of E-TC mean that future efforts can focus on understanding its mesoscale functions and how it regulates neuronal network activity and behaviour in physiological and pathological conditions.

Ca(V)1 and Ca(V)2 channels engage distinct modes of Ca(2+) signaling to control CREB-dependent gene expression.

Activity-dependent gene expression triggered by Ca(2+) entry into neurons is critical for learning and memory, but whether specific sources of Ca(2+) act distinctly or merely supply Ca(2+) to a common pool remains uncertain. Here, we report that both signaling modes coexist and pertain to Ca(V)1 and Ca(V)2 channels, respectively, coupling membrane depolarization to CREB phosphorylation and gene expression. Ca(V)1 channels are advantaged in their voltage-dependent gating and use nanodomain Ca(2+) to drive local CaMKII aggregation and trigger communication with the nucleus. In contrast, Ca(V)2 channels must elevate [Ca(2+)](i) microns away and promote CaMKII aggregation at Ca(V)1 channels. Consequently, Ca(V)2 channels are ~10-fold less effective in signaling to the nucleus than are Ca(V)1 channels for the same bulk [Ca(2+)](i) increase. Furthermore, Ca(V)2-mediated Ca(2+) rises are preferentially curbed by uptake into the endoplasmic reticulum and mitochondria. This source-biased buffering limits the spatial spread of Ca(2+), further attenuating Ca(V)2-mediated gene expression.

Chronic Neuronal Inactivity Utilizes the mTOR-TFEB Pathway to Drive Transcription-Dependent Autophagy for Homeostatic Up-Scaling.

Activity-dependent changes in protein expression are critical for neuronal plasticity, a fundamental process for the processing and storage of information in the brain. Among the various forms of plasticity, homeostatic synaptic up-scaling is unique in that it is induced primarily by neuronal inactivity. However, precisely how the turnover of synaptic proteins occurs in this homeostatic process remains unclear. Here, we report that chronically inhibiting neuronal activity in primary cortical neurons prepared from embryonic day (E)18 Sprague Dawley rats (both sexes) induces autophagy, thereby regulating key synaptic proteins for up-scaling. Mechanistically, chronic neuronal inactivity causes dephosphorylation of ERK and mTOR, which induces transcription factor EB (TFEB)-mediated cytonuclear signaling and drives transcription-dependent autophagy to regulate αCaMKII and PSD95 during synaptic up-scaling. Together, these findings suggest that mTOR-dependent autophagy, which is often triggered by metabolic stressors such as starvation, is recruited and sustained during neuronal inactivity to maintain synaptic homeostasis, a process that ensures proper brain function and if impaired can cause neuropsychiatric disorders such as autism.SIGNIFICANCE STATEMENT In the mammalian brain, protein turnover is tightly controlled by neuronal activation to ensure key neuronal functions during long-lasting synaptic plasticity. However, a long-standing question is how this process occurs during synaptic up-scaling, a process that requires protein turnover but is induced by neuronal inactivation. Here, we report that mTOR-dependent signaling, which is often triggered by metabolic stressors such as starvation, is "hijacked" by chronic neuronal inactivation, which then serves as a nucleation point for transcription factor EB (TFEB) cytonuclear signaling that drives transcription-dependent autophagy for up-scaling. These results provide the first evidence of a physiological role of mTOR-dependent autophagy in enduing neuronal plasticity, thereby connecting major themes in cell biology and neuroscience via a servo loop that mediates autoregulation in the brain.

Differential regulation of phosphorylation, structure, and stability of circadian clock protein FRQ isoforms.

Neurospora crassa is an important model organism for circadian clock research. The Neurospora core circadian component FRQ protein has two isoforms, large FRQ (l-FRQ) and small FRQ (s-FRQ), of which l-FRQ bears an additional N-terminal 99-amino acid fragment. However, how the FRQ isoforms operate differentially in regulating the circadian clock remains elusive. Here, we show l-FRQ and s-FRQ play different roles in regulating the circadian negative feedback loop. Compared to s-FRQ, l-FRQ is less stable and undergoes hypophosphorylation and faster degradation. The phosphorylation of the C-terminal l-FRQ 794-aa fragment was markedly higher than that of s-FRQ, suggesting the l-FRQ N-terminal 99-aa region may regulate the phosphorylation of the entire FRQ protein. Quantitative label-free LC/MS analysis identified several peptides that were differentially phosphorylated between l-FRQ and s-FRQ, which were distributed in FRQ in an interlaced fashion. Furthermore, we identified two novel phosphorylation sites, S765 and T781; mutations S765A and T781A showed no significant effects on conidiation rhythmicity, although T781 conferred FRQ stability. These findings demonstrate that FRQ isoforms play differential roles in the circadian negative feedback loop and undergo different regulations of phosphorylation, structure, and stability. The l-FRQ N-terminal 99-aa region plays an important role in regulating the phosphorylation, stability, conformation, and function of the FRQ protein. As the FRQ circadian clock counterparts in other species also have isoforms or paralogues, these findings will also further our understanding of the underlying regulatory mechanisms of the circadian clock in other organisms based on the high conservation of circadian clocks in eukaryotes.

Centromere Plasticity With Evolutionary Conservation and Divergence Uncovered by Wheat 10+ Genomes.

Centromeres (CEN) are the chromosomal regions that play a crucial role in maintaining genomic stability. The underlying highly repetitive DNA sequences can evolve quickly in most eukaryotes, and promote karyotype evolution. Despite their variability, it is not fully understood how these widely variable sequences ensure the homeostasis of centromere function. In this study, we investigated the genetics and epigenetics of CEN in a population of wheat lines from global breeding programs. We captured a high degree of sequences, positioning, and epigenetic variations in the large and complex wheat CEN. We found that most CENH3-associated repeats are Cereba element of retrotransposons and exhibit phylogenetic homogenization across different wheat lines, but the less-associated repeat sequences diverge on their own way in each wheat line, implying specific mechanisms for selecting certain repeat types as functional core CEN. Furthermore, we observed that CENH3 nucleosome structures display looser wrapping of DNA termini on complex centromeric repeats, including the repositioned CEN. We also found that strict CENH3 nucleosome positioning and intrinsic DNA features play a role in determining centromere identity among different lines. Specific non-B form DNAs were substantially associated with CENH3 nucleosomes for the repositioned centromeres. These findings suggest that multiple mechanisms were involved in the adaptation of CENH3 nucleosomes that can stabilize CEN. Ultimately, we proposed a remarkable epigenetic plasticity of centromere chromatin within the diverse genomic context, and the high robustness is crucial for maintaining centromere function and genome stability in wheat 10+ lines as a result of past breeding selections.

Bacterial Surface Appendages Modulate the Antimicrobial Activity Induced by Nanoflake Surfaces on Titanium.

Bioinspired nanotopography is a promising approach to generate antimicrobial surfaces to combat implant-associated infection. Despite efforts to develop bactericidal 1D structures, the antibacterial capacity of 2D structures and their mechanism of action remains uncertain. Here, hydrothermal synthesis is utilized to generate two 2D nanoflake surfaces on titanium (Ti) substrates and investigate the physiological effects of nanoflakes on bacteria. The nanoflakes impair the attachment and growth of Escherichia coli and trigger the accumulation of intracellular reactive oxygen species (ROS), potentially contributing to the killing of adherent bacteria. E. coli surface appendages type-1 fimbriae and flagella are not implicated in the nanoflake-mediated modulation of bacterial attachment but do influence the bactericidal effects of nanoflakes. An E. coli ΔfimA mutant lacking type-1 fimbriae is more susceptible to the bactericidal effects of nanoflakes than the parent strain, while E. coli cells lacking flagella (ΔfliC) are more resistant. The results suggest that type-1 fimbriae confer a cushioning effect that protects bacteria upon initial contact with the nanoflake surface, while flagella-mediated motility can lead to elevated membrane abrasion. This finding offers a better understanding of the antibacterial properties of nanoflake structures that can be applied to the design of antimicrobial surfaces for future medical applications.

Enhanced Structural VS4 Grown onto Hollow Carbon Mesoporous Spheres via Surficial Bonding for High Cycling Stability in Sodium-Ion Batteries.

Transition metal sulfides are recognized as an excellent alternative to sodium ion anodes ascribed to the outstanding theoretical capacity. The unique crystal arrangement of VS4 gives it exceptional theoretical capacity, despite challenges like insufficient electrical conductivity and undesirable volume expansion. Herein, a novel stabilized anode featuring a distinctive 3D hollow spherical structure is proposed, providing a simple strategy to synthesize such anodes for VS4-HCMSs bonded via C-O-S and V-O-C interfaces. The kinetic investigations and density functional theory reveal that the unique structure connected by interfacial bonds enhances Na+ transport rate and charge transfer efficiency, while carbon greatly mitigates the volume expansion. Unsurprisingly, the VS4-HCMSs exhibit an impressive first-cycle Coulombic efficiency of 91.31% and an ultrahigh reversible capacity of 612 mAh g-1 after 300 cycles at 0.5 A g-1, even exhibit the reversible capacity of 498.8 mAh g-1 after 1000 cycles at 5 A g-1. Additionally, the NaFePO4//VS4-HCMSs full cell is cycled for 200 cycles at 0.2 C and powered the light-emitting diodes for up to 30 minutes afterward. Overall, this work enhances the conductivity and stability of the material by combining VS4 with hollow carbon mesoporous spheres through interfacial bonding, offering an efficient strategy to anode materials in sodium-ion batteries.

Silencing lncRNA-DARS-AS1 suppresses nonsmall cell lung cancer progression by stimulating miR-302a-3p to inhibit ACAT1 expression.

Long noncoding RNAs (LncRNAs) have been gaining attention as potential therapeutic targets for lung cancer. In this study, we investigated the expression and biological behavior of lncRNA DARS-AS1, its predicted interacting partner miR-302a-3p, and ACAT1 in nonsmall cell lung cancer (NSCLC). The transcript level of DARS-AS1, miR-302a-3p, and ACAT1 was analyzed using qRT-PCR. Endogenous expression of ACAT1 and the expression of-and changes in-AKT/ERK pathway-related proteins were determined using western blotting. MTS, Transwell, and apoptosis experiments were used to investigate the behavior of cells. The subcellular localization of DARS-AS1 was verified using FISH, and its binding site was verified using dual-luciferase reporter experiments. The binding of DARS-AS1 to miR-302a-3p was verified using RNA co-immunoprecipitation. In vivo experiments were performed using a xenograft model to determine the effect of DARS-AS1 knockout on ACAT1 and NSCLC. lncRNA DARS-AS1 was upregulated in NSCLC cell lines and tissues and the expression of lncRNA DARS-AS1 was negatively correlated with survival of patients with NSCLC. Knockdown of DARS-AS1 inhibited the malignant behaviors of NSCLC via upregulating miR-302a-3p. miR-302a-3p induced suppression of malignancy through regulating oncogene ACAT1. This study demonstrates that the DARS-AS1-miR-302a-3p-ACAT1 pathway plays a key role in NSCLC.

A Comprehensive Assessment of the Chinese Version of the Duke Activity Status Index in Patients with Cardiovascular Diseases.

Background: Exercise capacity serves as a direct representation of cardiac function. The Duke Activity Status Index (DASI), a self-administered 12-item questionnaire, covers aspects of daily living, household tasks, sexual function, and physical activity. Although widely used to evaluate exercise capacity, its validation in Chinese cardiovascular disease (CVD) patients has not been thoroughly explored. Considering the significant cultural and lifestyle differences between China and Western countries, which may influence Chinese patients' comprehension and responses to DASI, our objective is to culturally adapt DASI for Chinese patients with CVD to ensure its precision in assessing exercise capacity. Methods: The cultural adaptation of the original DASI questionnaire into Chinese followed a rigorous process to ensure its validity, reliability, and sensitivity to Chinese CVD patients. The study included 107 outpatients diagnosed with CVD who completed the DASI and cardiopulmonary exercise testing (CPET). Cronbach's alpha, Spearman correlation, and factor analysis were utilized to test reliability and validity. Receiver operating characteristic (ROC) curve analysis was employed to assess the prognostic utility of the DASI. Results: Participants had a mean DASI score of 39.40 ± 10.75 and a peak oxygen uptake (Peak VO 2 ) of 19.53 ± 5.89 mL/min/kg. The Chinese version of the DASI exhibited satisfactory reliability and validity in CVD patients, with a Chronbach's alpha coefficient of 0.706. The DASI score demonstrated a moderate correlation with Peak VO 2 measured by CPET (r = 0.67, p < 0.001). Factor analysis yielded three factors, accounting for 56.76% of the total variance, with factor 1 contributing to 26.38% of the variance. ROC curve analysis demonstrated that the DASI exhibited discriminative utility in the identification of patients with improved long-term prognosis (p < 0.001). The ROC curve had an area of 0.788 [95% confidence interval (CI) = 0.704-0.871]. The DASI score ≥ 36.85 served as the optimal threshold for enhanced long-term prognosis, exhibiting a sensitivity of 0.80 and a specificity of 0.69. Conclusions: The culturally adapted DASI questionnaire is a straightforward and efficient tool for reasonably evaluating exercise capacity in Chinese CVD patients.

RUNX1 promotes proliferation and migration in non-small cell lung cancer cell lines via the mTOR pathway.

RUNX1, a member of the RUNX family of metazoan transcription factors, participates in the regulation of differentiation, proliferation, and other processes involved in growth and development. It also functions in the occurrence and development of tumors. However, the role and mechanism of action of RUNX1 in non-small cell lung cancer (NSCLC) are not yet clear. We used a bioinformatics approach as well as in vitro and in vivo assays to evaluate the role of RUNX1 in NSCLC as the molecular mechanisms underlying its effects. Using the TCGA, GEO, GEPIA (Gene Expression Profiling Interactive Analysis), and Kaplan-Meier databases, we screened the differentially expressed genes (DEGs) and found that RUNX1 was highly expressed in lung cancer and was associated with a poor prognosis. Immunohistochemical staining based on tissue chips from 110 samples showed that the expression of RUNX1 in lung cancer tissues was higher than that in adjacent normal tissues and was positively correlated with lymph node metastasis and TNM staging. In vitro experiments, we found that RUNX1 overexpression promoted cell proliferation and migration functions and affected downstream functional proteins by regulating the activity of the mTOR pathway, as confirmed by an analysis using the mTOR pathway inhibitor rapamycin. In addition, RUNX1 affected PD-L1 expression via the mTOR pathway. These results indicate that RUNX1 is a potential therapeutic target for NSCLC.

Effects of paternal deprivation on empathetic behavior and the involvement of oxytocin receptors in the anterior cingulate cortex.

Paternal deprivation (PD) impairs social cognition and sociality and increases levels of anxiety-like behavior. However, whether PD affects the levels of empathy in offspring and its underlying mechanisms remain unknown. The present study found that PD increased anxiety-like behavior in mandarin voles (Microtus mandarinus), impaired sociality, reduced the ability of emotional contagion, and the level of consolation behavior. Meanwhile, PD reduced OT neurons in the paraventricular nucleus (PVN) in both male and female mandarin voles. PD decreased the level of OT receptor (OTR) mRNA in the anterior cingulate cortex (ACC) of male and female mandarin voles. Besides, OTR overexpression in the ACC reversed the PD-induced changes in anxiety-like behavior, social preference, emotional contagion, and consolation behavior. Interference of OTR expression in the ACC increased levels of anxiety-like behaviors, while it reduced levels of sociality, emotional contagion, and consolation. These results revealed that the OTR in the ACC is involved in the effects of PD on empathetic behaviors, and provide mechanistic insight into how social experiences affect empathetic behaviors.

Quantum-centric high performance computing for quantum chemistry.

High performance computing (HPC) is renowned for its capacity to tackle complex problems. Meanwhile, quantum computing (QC) provides a potential way to accurately and efficiently solve quantum chemistry problems. The emerging field of quantum-centric high performance computing (QCHPC), which merges these two powerful technologies, is anticipated to enhance computational capabilities for solving challenging problems in quantum chemistry. The implementation of QCHPC for quantum chemistry requires interdisciplinary research and collaboration across multiple fields, including quantum chemistry, quantum physics, computer science and so on. This perspective provides an introduction to the quantum algorithms that are suitable for deployment in QCHPC, focusing on conceptual insights rather than technical details. Parallel strategies to implement these algorithms on quantum-centric supercomputers are discussed. We also summarize high performance quantum emulating simulators, which are considered a viable tool to explore QCHPC. We conclude with challenges and outlooks in this field.

The combined effects of depression or anxiety with high-sensitivity C-reactive protein in predicting the prognosis of coronary heart disease patients.

BACKGROUND: Depression, anxiety and high-sensitivity C-reactive protein (hs-CRP) are individually associated with poor prognosis in patients with coronary heart disease (CHD). However, the combined effects of depression with inflammation or anxiety with inflammation on the prognosis have been rarely explored. METHODS: This prospective cohort study included 414 patients diagnosed with CHD. The Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to assess depression and anxiety. A score ≥ 5 points was defined as elevated depression or anxiety. High hs-CRP was defined as ≥ 3 mg/L. Follow-up was performed 2 years after the patients were discharged. The clinical results included noncardiac readmission, cardiac readmission, major cardiovascular events (MACEs), and composite events. The composite events included noncardiac readmission and MACEs. The Cox proportional hazard regression model was used to analyze the prognostic risk. RESULTS: After full adjustment, patients with elevated depression and high hs-CRP had a higher risk in predicting noncardiac readmission (hazard ratio (HR) = 3.87, 95% confidence interval (CI) = 1.10-9.02, p = 0.002) and composite events (HR = 1.93, 95% CI = 1.13-3.30, p = 0.016) than those with high hs-CRP alone. For the anxiety and hs-CRP group, high hs-CRP alone predicted a higher risk of noncardiac readmission (HR = 3.32, 95% CI = 1.57-7.03, p = 0.002) and composite events (HR = 1.75, 95% CI = 1.12-2.76, p = 0.015) than references. Elevated anxiety had no significant effects on all the endpoints. Furthermore, we didn't find interactions between depression and hs-CRP or anxiety and hs-CRP. CONCLUSION: In patients with CHD, elevated depression with high hs-CRP was found to be significant in predicting the risk of noncardiac readmission and composite events. Early diagnosis and treatment of depression with inflammation are necessary in CHD patients.

Forecasting the trend of tuberculosis incidence in Anhui Province based on machine learning optimization algorithm, 2013-2023.

Tuberculosis has been one of the most common communicable diseases raising global concerns. Accurately predicting the incidence of Tuberculosis remains challenging. Here we constructed a time-series analysis and fusion tool using multi-source data, and aimed to more accurately predict the incidence trend of tuberculosis of Anhui Province from 2013 to 2023. Random forest algorithm (RF), Feature Recursive Elimination (RFE) and Least absolute shrinkage and selection operator (LASSO) were implemented to improve the derivation of features related to infectious diseases and feature work. Based on the characteristics of infectious disease data, a model of RF-RFE-LASSO integrated particle swarm optimization multiple inputs long short term memory recurrent neural network (RRL-PSO-MiLSTM) was created to perform more accurate prediction. Results showed that the PSO-MiLSTM achieved excellent prediction results compared with common single-input and multi-input time-series models (test set MSE:42.3555, MAE: 59.3333, RMSE: 146.7237, MAPE: 2.1133, R2: 0.8634). PSO-MiLSTM enriches and complements the methodological research content of calibrating the time-series predictive analysis of infectious diseases using multi-source data, and can be used as a brand-new benchmark for the analysis of influencing factors and trend prediction of infectious diseases at the public health level in the future, as well as providing a reference for incidence rate prediction of infectious diseases.

Circulating retinol and 25(OH)D contents and their association with symptoms in children with chronic tic disorders.

The present study measured serum levels of vitamin A (VA) and vitamin D (VD) in children with chronic tic disorders (CTD) and investigated their potential association with CTD and comorbidity of attention deficit hyperactivity disorder (ADHD) and the association of their co-insufficiencies or deficiencies with CTD symptoms. A total of 176 children (131 boys and 45 girls, median age of 9 years) with CTD were recruited as the CTD group. During the same period, 154 healthy children were selected as the healthy control (HC) cohort. Circulating retinol and 25-hydroxyvitamin D (25[OH]D) levels were measured for all participants using high-performance liquid chromatography (HPLC) and tandem mass spectrometry. The Yale Global Tic Severity Scale (YGTSS) was employed for the assessment of tic status and CTD impairment. The Swanson, Nolan, and Pelham Rating Scale (SNAP-IV) and the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) were used to evaluate comorbidity symptoms. CTD pediatric participants exhibited markedly diminished circulating retinol and 25(OH)D levels compared to HCs. Moreover, VA and VD deficiencies and their co-insufficiencies/deficiencies were more prevalent in CTD participants than HCs. Circulating 25(OH)D levels were inversely proportional to the YGTSS motor tic scores. YGTSS scores in CTD children with only VA or VD insufficiency or deficiency or with VA and VD co-insufficiency/deficiency did not differ from those in CTD children with normal VA and VD. CTD children with comorbid ADHD displayed reduced circulating retinol and 25(OH)D concentrations and elevated prevalence of VD deficiency compared to CTD participants without comorbid ADHD. Lower serum retinol content was intricately linked to the presence of elevated CTD and comorbid ADHD. VA and VD deficiencies and their co-insufficiencies/deficiencies were markedly enhanced in CTD pediatric participants compared to HCs. Lower VA concentration was linked to the presence of enhanced CTD and comorbid ADHD. Therefore, children with CTD, especially with comorbid ADHD, may be at a higher risk of VA or VD deficiency, which may prompt the clinicians to consider whether blood tests for VA and VD in CTD children would be helpful for clinical care.

Antiviral CD8+ T-cell immune responses are impaired by cigarette smoke and in COPD.

BACKGROUND: Virus infections drive COPD exacerbations and progression. Antiviral immunity centres on the activation of virus-specific CD8+ T-cells by viral epitopes presented on major histocompatibility complex (MHC) class I molecules of infected cells. These epitopes are generated by the immunoproteasome, a specialised intracellular protein degradation machine, which is induced by antiviral cytokines in infected cells. METHODS: We analysed the effects of cigarette smoke on cytokine- and virus-mediated induction of the immunoproteasome in vitro, ex vivo and in vivo using RNA and Western blot analyses. CD8+ T-cell activation was determined in co-culture assays with cigarette smoke-exposed influenza A virus (IAV)-infected cells. Mass-spectrometry-based analysis of MHC class I-bound peptides uncovered the effects of cigarette smoke on inflammatory antigen presentation in lung cells. IAV-specific CD8+ T-cell numbers were determined in patients' peripheral blood using tetramer technology. RESULTS: Cigarette smoke impaired the induction of the immunoproteasome by cytokine signalling and viral infection in lung cells in vitro, ex vivo and in vivo. In addition, cigarette smoke altered the peptide repertoire of antigens presented on MHC class I molecules under inflammatory conditions. Importantly, MHC class I-mediated activation of IAV-specific CD8+ T-cells was dampened by cigarette smoke. COPD patients exhibited reduced numbers of circulating IAV-specific CD8+ T-cells compared to healthy controls and asthmatics. CONCLUSION: Our data indicate that cigarette smoke interferes with MHC class I antigen generation and presentation and thereby contributes to impaired activation of CD8+ T-cells upon virus infection. This adds important mechanistic insight on how cigarette smoke mediates increased susceptibility of smokers and COPD patients to viral infections.

Association between sleep duration and metabolic syndrome: linear and nonlinear Mendelian randomization analyses.

BACKGROUND: Observational studies have found that both short and long sleep duration are associated with increased risk of metabolic syndrome (MetS). This study aimed to examine the associations of genetically determined sleep durations with MetS and its five components (i.e., central obesity, high blood pressure, dyslipidemia, hypertriglyceridemia, and hyperglycemia) among a group of elderly population. METHODS: In 335,727 participants of White British from the UK Biobank, linear Mendelian randomization (MR) methods were first employed to examine the causal association of genetically predicted continuous sleep duration with MetS and its each component. Nonlinear MR analyses were performed to determine the nonlinearity of these associations. The causal associations of short and long sleep duration with MetS and its components were further assessed by using genetic variants that associated with short (≤ 6 h) and long sleep (≥ 9 h) durations. RESULTS: Linear MR analyses demonstrated that genetically predicted 1-h longer sleep duration was associated with a 13% lower risk of MetS, a 30% lower risk of central obesity, and a 26% lower risk of hyperglycemia. Non-linear MR analyses provided evidence for non-linear associations of genetically predicted sleep duration with MetS and its five components (all P values < 0.008). Genetically predicted short sleep duration was moderately associated with MetS and its four components, including central obesity, dyslipidemia, hypertriglyceridemia, and hyperglycemia (all P values < 0.002), whereas genetically long sleep duration was not associated with MetS and any of its components. CONCLUSIONS: Genetically predicted short sleep duration, but not genetically predicted long sleep duration, is a potentially causal risk factor for MetS.