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Acetylation is an important, reversible posttranslational modification to a protein. In a previous study, we found that there were a large number of acetylated sites in various nutrient storage proteins of the silkworm haemolymph. In this study, we confirmed that acetylation can affect the stability of nutrient storage protein Bombyx mori apolipophorin‐III (BmApoLp‐III). First, the expression of BmApoLp‐III could be upregulated when BmN cells were treated with the deacetylase inhibitor panobinostat (LBH589); similarly, the expression was downregulated when the cells were treated with the acetylase inhibitor C646. Furthermore, the increase in acetylation by LBH589 could inhibit the degradation and improve the accumulation of BmApoLp‐III in BmN cells treated with cycloheximide and MG132 respectively. Moreover, we found that an increase in acetylation could decrease the ubiquitination of BmApoLp‐III and vice versa; therefore, we predicted that acetylation could improve the stability of BmApoLp‐III by competing for ubiquitination and inhibiting the protein degradation pathway mediated by ubiquitin. Additionally, BmApoLp‐III had an antiapoptosis function that increased after LBH589 treatment, which might have been due to the improved protein stability after acetylation. These results have laid the foundation for further study on the mechanism of acetylation in regulating the storage and utilization of silkworm nutrition. [ABSTRACT FROM AUTHOR]

The interaction forces of a fractured femur among the bone, muscle, and other soft tissues are not well understood. Only a small number of in vivo measurements have been made and with many limitations. Mathematical modeling is a useful alternative, overcoming limitations and allowing investigation of hypothetical simulated reductions. We aimed to develop a model to help understand best practices in fracture reduction and to form a base to develop new technologies and procedures. The simulation environment allows muscle forces and moments to deform a fractured femur, and the behavior of forces during reduction can be found. Visual and numerical output of forces and moments during simulated reduction procedures are provided. The output can be probed throughout the reduction procedure down to the individual muscle's contribution. This is achieved by construction of an anatomically correct three-dimensional mathematical model of the lower extremity and muscles. Parameters are fully customizable and can be used to investigate simple, oblique, and some comminuted fractures. Results were compared with published in vivo measurements and were of the same magnitude. A simple midshaft fracture had a maximum resulting force of 428 N, whereas traction from the hip reached a maximum value of 893 N at 60 mm of displacement. Monte Carlo analysis revealed that the deforming force was most sensitive to the muscles' rest lengths. The developed model provides greater understanding and detail than in vivo measurements have to date. It allows new treatment procedures to be developed and importantly to assess the outcome. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1159-1165, 2008 [ABSTRACT FROM AUTHOR]

A novel HLA‐B allele, B*15:179:02, has been identified during typing of donors in Anhui province, China. [ABSTRACT FROM AUTHOR]

Objectives: Recent immunologic study of the adaptive immune repertoire in the subglottic airway demonstrated high-frequency T cell clones that do not overlap between individuals. However, the anatomic distribution and antigenic target of the T cell repertoire in the proximal airway mucosa remain unresolved., Methods: Single-cell RNA sequencing of matched scar and unaffected mucosa from idiopathic subglottic stenosis patients (iSGS, n = 32) was performed and compared with airway mucosa from healthy controls (n = 10). T cell receptor (TCR) sequences were interrogated via similarity network analysis to explore antigenic targets using the published algorithm: Grouping of Lymphocyte Interactions by Paratope Hotspots (GLIPH2)., Results: The mucosal T cell repertoire in healthy control airways consisted of highly expressed T cell clones conserved across anatomic subsites (trachea, bronchi, bronchioles, and lung). In iSGS, high-frequency clones were equally represented in both scar and adjacent non-scar tissue. Significant differences in repertoire structure between iSGS scar and unaffected mucosa was observed, driven by unique low-frequency clones. GLIPH2 results suggest low-frequency clones share targets between multiple iSGS patients., Conclusion: Healthy airway mucosa has a highly conserved T cell repertoire across multiple anatomic subsites. Similarly, iSGS patients have highly expressed T cell clones present in both scar and unaffected mucosa. iSGS airway scar possesses an abundance of less highly expanded clones with predicted antigen targets shared between patients. Interrogation of these shared motifs suggests abundant adaptive immunity to viral targets in iSGS airway scar. These results provide insight into disease pathogenesis and illuminate new treatment strategies in iSGS., Level of Evidence: NA Laryngoscope, 134:3245-3252, 2024., (© 2024 The Authors. The Laryngoscope published by Wiley Periodicals LLC on behalf of The American Laryngological, Rhinological and Otological Society, Inc.)

Objectives: Recent translational scientific efforts in subglottic stenosis (SGS) support a disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. Given the observed immune cell infiltrate in SGS, we sought to test the hypothesis that SGS cases possessed a low diversity (highly clonal) adaptive immune response when compared with healthy controls., Methods: Single cell RNA sequencing (scRNA-seq) of subglottic mucosal scar in iSGS (n = 24), iLTS (n = 8), and healthy controls (n = 7) was performed. T cell receptor (TCR) sequences were extracted, analyzed, and used to construct repertoire structure, compare diversity, interrogate overlap, and define antigenic targets using the Immunarch bioinformatics pipeline., Results: The proximal airway mucosa in health and disease are equally diverse via Hill framework quantitation (iSGS vs. iLTS vs. Control, p > 0.05). Repertoires do not significantly overlap between individuals (Morisita <0.02). Among iSGS patients, clonality of the TCR repertoire is driven by CD8+ T cells, and iSGS patients possess numerous TCRs targeting viral and intercellular pathogens. High frequency clonotypes do not map to known targets in public datasets., Conclusion: SGS cases do not possess a lower diversity adaptive immune infiltrate when compared with healthy controls. Interestingly, the TCR repertoire in both health and disease contains a restricted number of high frequency clonotypes that do not significantly overlap between individuals. The target of the high frequency clonotypes in health and disease remain unresolved., Level of Evidence: NA Laryngoscope, 134:1757-1764, 2024., (© 2023 The American Laryngological, Rhinological and Otological Society, Inc.)

Objectives: Idiopathic subglottic stenosis (iSGS) is an unexplained progressive fibrosis of the upper airway. iSGS almost exclusively affects women; as a result, female hormones (estrogen and progesterone) have been proposed to participate in the pathogenesis of iSGS. Our aim was to localize cell-specific gene expression of estrogen receptors (ESR1 and ESR2) and progesterone receptor (PGR) using an established iSGS single-cell RNA sequencing (scRNAseq) cell atlas., Study Design: Ex vivo molecular study of airway scar and healthy mucosa from iSGS patients., Methods: An established scRNAseq atlas consisting of 25,974 individually sequenced cells from subglottic scar (n = 7) or matched unaffected mucosa (n = 3) in iSGS patients was interrogated for RNA expression of ESR1, ESR2, and PGR. Results were quantified and compared across cell subsets, then visualized using Uniform Manifold Approximation and Projection (UMAP). Confirmatory protein assessment of endocrine receptors in fibroblasts from iSGS patients (n = 5) was performed via flow cytometry., Results: The proximal airway mucosa in iSGS patients demonstrates differential expression of endocrine receptors (ESR1, ESR2, PGR). Within airway scar, endocrine receptors are primarily expressed by fibroblasts, immune cells, and endothelial cells. Fibroblasts show strong ESR1 and PGR expression, while immune cells possess RNA for both ESR1 and ESR2. Endothelial cells predominantly express ESR2. Epithelial cells in unaffected mucosa express all three receptors, which are all reduced in airway scar., Conclusions: scRNAseq data localized endocrine receptor expression to specific cell subsets. These results provide the foundation for future work interrogating how hormone-dependent mechanisms promote, sustain, or participate in iSGS disease pathogenesis., Level of Evidence: NA; Basic science Laryngoscope, 133:3506-3511, 2023., (© 2023 The American Laryngological, Rhinological and Otological Society, Inc.)

Objectives: Recent translational scientific efforts in subglottic stenosis (SGS) support a disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune activation, and localized fibrosis. Yet despite recent advances, the genetic basis of SGS remains poorly understood. We sought to identify candidate risk genes associated with an SGS phenotype, investigate their biological function, and identify the cell types enriched for their expression., Methods: The Online Mendelian Inheritance in Man (OMIM) database was queried for single gene variants associated with an SGS phenotype. The functional intersections and molecular roles of the identified genes were explored using pathway enrichment analysis (PEA) computational methods. Cellular localization of the candidate risk genes was measured via transcriptional quantification in an established single cell RNA sequencing (scRNA-seq) atlas of the proximal airway., Results: Twenty genes associated with SGS phenotype were identified. PEA resulted in 24 significantly enriched terms including "cellular response to TGF-β," "epithelial-to-mesenchymal transition," and "adherens junctions." Mapping the 20 candidate risk genes to the scRNA-seq atlas found 3 (15%) genes were enriched in epithelial cells, 3 (15%) in fibroblasts, and 3 (15%) in endothelial cells. 11 (55%) genes were expressed ubiquitously among tissue types. Interestingly, immune cells were not significantly enriched for candidate risk genes., Conclusion: We identify and provide biologic context for 20 genes associated with fibrotic disease of the proximal airway and form the foundation for future detailed genetic study., Level of Evidence: N/A Laryngoscope, 133:3049-3056, 2023., (© 2023 The American Laryngological, Rhinological and Otological Society, Inc.)

Background The systemic inflammation that occurs after exposure to cardiopulmonary bypass (CPB), which is especially severe in neonatal patients, is associated with poorer outcomes and is not well understood. In order to gain deeper insight into how exposure to bypass activates inflammatory responses in circulating leukocytes, we studied changes in microRNA (miRNA) expression during and after exposure to bypass. miRNAs are small noncoding RNAs that have important roles in modulating protein levels and function of cells. Methods and Results We performed miRNA-sequencing on leukocytes isolated from neonatal patients with CPB (n=5) at 7 time points during the process of CPB, including before the initiation of bypass, during bypass, and at 3 time points during the first 24 hours after weaning from bypass. We identified significant differentially expressed miRNAs using generalized linear regression models, and miRNAs were defined as statistically significant using a false discovery rate-adjusted P <0.05. We identified gene targets of these miRNAs using the TargetScan database and identified significantly enriched biological pathways for these gene targets. We identified 54 miRNAs with differential expression during and after CPB. These miRNAs clustered into 3 groups, including miRNAs that were increased during and after CPB (3 miRNAs), miRNAs that decreased during and after CPB (10 miRNAs), and miRNAs that decreased during CPB but then increased 8 to 24 hours after CPB. A total of 38.9% of the target genes of these miRNAs were significantly differentially expressed in our previous study. miRNAs with altered expression levels are predicted to significantly modulate pathways related to inflammation and signal transduction. Conclusions The unbiased profiling of the miRNA changes that occur in the circulating leukocytes of patients with bypass provides deeper insight into the mechanisms that underpin the systemic inflammatory response that occurs in patients after exposure to CPB. These data will help the development of novel treatments and biomarkers for bypass-associated inflammation.

Background: Data on tenofovir alafenamide fumarate (TAF) for preventing mother-to-child transmission of hepatitis B virus (HBV) are lacking., Aims: To investigate the efficacy and safety of TAF therapy for preventing hepatitis B mother-to-child transmission., Methods: Mothers with chronic HBV infection, positive for hepatitis B e-antigen and with HBV DNA >200 000 IU/mL received TAF for preventing mother-to-child transmission were enrolled retrospectively from multiple centres with data collection on mother-infant dyads up to postpartum week 24-28. Primary measurements were the mother-to-child transmission rate and infants' malformation rate. Secondary assessments included maternal HBV DNA reduction at delivery, and maternal or infant adverse events during follow up., Results: Among 71 mothers enrolled, the mean (±SD) age was 30.3 (±2.2) years. TAF was initiated during the second or third trimester and continued to delivery with a mean (±SD) duration of 12.8 (±4.0) weeks. At delivery, 85.9% (61/71) of the mothers achieved HBV DNA <200 000 IU/L. Seventy-three infants (two sets of twins) were born from mothers treated with TAF and none had congenital defects or malformations. All infants received HBV immunoglobulin and vaccine at birth with additional HBV vaccinations at one and six months. At age 24-28 weeks, all infants had negative hepatitis B surface antigen and undetectable levels of HBV DNA (<100 IU/mL). Body weight, height, and head circumferences were comparable to national standards for physical development. No severe adverse effects were reported in either mothers or infants., Conclusions: TAF for highly viraemic mothers effectively prevented mother-to-child transmission of hepatitis B. There were no safety concerns for either mothers or infants with 24-28 weeks of follow up., (© 2020 John Wiley & Sons Ltd.)

Orexin is a member of neuropeptides which was first identified in the hypothalamus. The globus pallidus is a key structure in the basal ganglia, which is involved in both normal motor function and movement disorders. Morphological studies have shown the expression of both OX1 and OX2 receptors in the globus pallidus. Employing single unit extracellular recordings and behavioural tests, the direct in vivo electrophysiological and behavioural effects of orexin-A in the globus pallidus were studied. Micro-pressure administration of orexin-A significantly increased the spontaneous firing rate of pallidal neurons. Correlation analysis revealed a negative correlation between orexin-A induced excitation and the basal firing rate. Furthermore, application of the specific OX1 receptor antagonist, SB-334867, decreased the firing rate of pallidal neurons, suggesting that endogenous orexinergic systems modulate the firing activity of pallidal neurons. Orexin-A increased the excitability of pallidal neurons through both OX1 and OX2 receptors. In 6-hydroxydopamine parkinsonian rats, orexin-A-induced increase in firing rate of pallidal neurons was stronger than that in normal rats. Immunostaining revealed positive OX1 receptor expression in the globus pallidus of both normal and parkinsonian rats. Finally, postural test showed that unilateral microinjection of orexin-A led to contralateral deflection in the presence of systemic haloperidol administration. Further elevated body swing test revealed that pallidal orexin-A and SB-334867 induced contralateral-biased swing and ipsilateral-biased swing respectively. Based on the electrophysiological and behavioural findings of orexin-A in the globus pallidus, the present findings may provide a rationale for the pathogenesis and treatment of Parkinson's disease., (© 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Background & Aims: The morbidity and mortality of spontaneous bacterial peritonitis (SBP) are high among patients with cirrhosis; however, the mechanisms of SBP pathogenesis are poorly understood. This study aimed to determine the role of the vitamin D-LL-37 pathway in the pathogenesis and treatment in patients with cirrhosis and SBP., Methods: Serum 25-hydroxyvitamin D concentrations of 119 patients with chronic liver diseases were tested. Vitamin D receptor (VDR) and LL-37 in peritoneal leucocytes of cirrhotic and ascitic patients with SBP were detected and compared with those without SBP. Then the peritoneal macrophages of non-infected patients were cultured and activated by lipopolysaccharide (LPS) to analyse the changes of VDR and LL-37 expressions after incubation with vitamin D., Results: Vitamin D deficiency or insufficiency was found in all of patients with cirrhosis. LPS inhibited VDR and LL-37 expression in peritoneal macrophages [1.3-fold decrease (P = 0.003) and 20-fold decrease (P = 0.010) respectively]. However, vitamin D could reverse the inhibition of both VDR and LL-37 [1.5-fold increase (P = 0.001) and 2000-fold increase (P < 0.001) respectively]. The effect of the incubation time following vitamin D supplementation was significant for LL-37 expression, with a peak expression found at 36 h (P < 0.001)., Conclusions: When vitamin D levels were low, bacteria inhibited VDR and LL-37 responses in peritoneal macrophages as a mechanism to evade antibacterial defence. Vitamin D supplementation could up-regulate peritoneal macrophage VDR and LL-37 expressions, which resulted in an enhanced immunological defence against SBP in patients with cirrhosis and ascites., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)