Immunophenotypic variations in syphilis: insights from Mendelian randomization analysis.

Background: Infection with Treponema pallidum instigates complex immune responses. Prior research has suggested that persistent Treponema pallidum infection can manipulate host immune responses and circumvent host defenses. However, the precise role of immune cells in Treponema pallidum infection across different stages remains a contentious issue. Methods: Utilizing summary data from genome-wide association studies, we employed a two-sample Mendelian randomization method to investigate the association between 731 immunophenotypes and syphilis. Syphilis was categorized into early and late stages in this study to establish a more robust correlation and minimize bias in database sources. Results: Our findings revealed that 33, 36, and 27 immunophenotypes of peripheral blood were associated with syphilis (regardless of disease stage), early syphilis and late syphilis, respectively. Subsequent analysis demonstrated significant variations between early and late syphilis in terms of immunophenotypes. Specifically, early syphilis showcased activated, secreting, and resting regulatory T cells, whereas late syphilis was characterized by resting Treg cells. More B cells subtypes emerged in late syphilis. Monocytes in early syphilis exhibited an intermediate and non-classical phenotype, transitioning to classical in late syphilis. Early syphilis featured naive T cells, effector memory T cells, and terminally differentiated T cells, while late syphilis predominantly presented terminally differentiated T cells. Immature myeloid-derived suppressor cells were evident in early syphilis, whereas the dendritic cell immunophenotype was exclusive to late syphilis. Conclusion: Multiple immunophenotypes demonstrated associations with syphilis, showcasing substantial disparities between the early and late stages of the disease. These findings hold promise for informing immunologically oriented treatment strategies, paving the way for more effective and efficient syphilis interventions.

Cancer on motors: How kinesins drive prostate cancer progression?

Prostate cancer causes numerous male deaths annually. Although great progress has been made in the diagnosis and treatment of prostate cancer during the past several decades, much about this disease remains unknown, especially its pathobiology. The kinesin superfamily is a pivotal group of motor proteins, that contains a microtubule-based motor domain and features an adenosine triphosphatase activity and motility characteristics. Large-scale sequencing analyses based on clinical samples and animal models have shown that several members of the kinesin family are dysregulated in prostate cancer. Abnormal expression of kinesins could be linked to uncontrolled cell growth, inhibited apoptosis and increased metastasis ability. Additionally, kinesins may be implicated in chemotherapy resistance and escape immunologic cytotoxicity, which creates a barrier to cancer treatment. Here we cover the recent advances in understanding how kinesins may drive prostate cancer progression and how targeting their function may be a therapeutic strategy. A better understanding of kinesins in prostate cancer tumorigenesis may be pivotal for improving disease outcomes in prostate cancer patients.

Co-transcriptional R-loops-mediated epigenetic regulation drives growth retardation and docetaxel chemosensitivity enhancement in advanced prostate cancer.

R-loops are prevalent three-stranded nucleic acid structures, comprising a DNA-RNA hybrid and a displaced single-stranded DNA, that frequently form during transcription and may be attributed to genomic stability and gene expression regulation. It was recently discovered that RNA modification contributes to maintain the stability of R-loops such as N6-methyladenosine (m6A). Yet, m6A-modified R-loops in regulating gene transcription remains poorly understood. Here, we demonstrated that insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) recognize R-loops in an m6A-dependent way. Consequently, IGF2BPs overexpression leads to increased overall R-loop levels, cell migration inhibition, and cell growth retardation in prostate cancer (PCa) via precluding the binding of DNA methyltransferase 1(DNMT1) to semaphorin 3 F (SEMA3F) promoters. Moreover, the K homology (KH) domains of IGF2BPs are required for their recognition of m6A-containing R-loops and are required for tumor suppressor functions. Overexpression of SEMA3F markedly enhanced docetaxel chemosensitivity in prostate cancer via regulating Hippo pathway. Our findings point to a distinct R-loop resolution pathway mediated by IGF2BPs, emphasizing the functional importance of IGF2BPs as epigenetic R-loop readers in transcriptional genetic regulation and cancer biology.The manuscript summarizes the new role of N6-methyladenosine in epigenetic regulation, we introduce the distinct R-loop resolution mediated by IGF2BP proteins in an m6A-dependent way, which probably lead to the growth retardation and docetaxel chemotherapy resistance in prostate cancer. Moreover, our findings first emphasized the functional importance of IGF2BPs as epigenetic R-loop readers in transcriptional genetic regulation and cancer biology. In addition, our research provides a novel RBM15/IGF2BPs/DNMT1 trans-omics regulation m6A axis, indicating the new crosstalk between RNA m6A methylation and DNA methylation in prostate cancer.

Neutrophil CD64 index as a potential blood biomarker for the diagnosis of neurosyphilis in secondary and tertiary syphilis: A retrospective study.

Objective: To examine the correlation of neutrophil CD64 (nCD64) index with neurosyphilis (NS) across different stages of syphilis. Methods: A total of 1243 syphilis patients at different stages (344 of primary, 385 of secondary, and 514 of tertiary) included in this study were divided into NS and non-NS (NNS). Correlations of nCD64 index with currently used syphilis biomarkers were explored using Spearman correlation test. Relationships between nCD64 index and NS at different stages were investigated by stratified analysis and restricted cubic spline model. The diagnostic performance of nCD64 index for NS was assessed by receiver operating characteristic (ROC) curve. Results: Significant statistical correlations of nCD64 index with cerebrospinal fluid (CSF) NS indicators were found in secondary and tertiary syphilis. Increased nCD64 index was associated with increased risk of NS in secondary and tertiary syphilis. ROC analysis values further confirmed the diagnostic potential of nCD64 index for NS. Marked decrease of nCD64 index was observed in NS patients after effective antisyphilitic treatments. Conclusions: The nCD64 index may help to the diagnosis of NS in secondary and tertiary syphilis.

Perioperative Adjunctive Esketamine for Postpartum Depression Among Women Undergoing Elective Cesarean Delivery: A Randomized Clinical Trial.

Importance: Postpartum depression (PPD) is one of the most common mental health conditions during the perinatal and postpartum periods, which can have adverse effects on both mother and infant. Objective: To investigate the efficacy of perioperative adjunctive esketamine administration after cesarean deliveries in the prevention of PPD. Design, Setting, and Participants: A single-center, double-blind, placebo-controlled, randomized clinical trial was conducted from January 1, 2022, to January 1, 2023, at Fujian Provincial Hospital among 298 women aged 18 to 40 years, with an American Society of Anesthesiologists grade I to III classification and singleton full-term pregnancies who were scheduled for elective cesarean deliveries. Primary analyses were performed on a modified intention-to-treat basis. Interventions: Patients were randomly assigned to the esketamine (n = 148) and control (n = 150) groups. Those in the esketamine group received a single intravenous injection of 0.25 mg/kg of esketamine immediately after fetal delivery, followed by 50 mg of esketamine as an adjuvant in patient-controlled intravenous analgesia for 48 hours after surgery. Saline was given to the control group of patients. Main Outcomes and Measures: The primary outcome was assessments of PPD symptoms by using the Edinburgh Postnatal Depression Scale (EPDS) at postpartum day 7. Positive screening for PPD was defined as a score of 10 or more points on the EPDS. In addition, the EPDS was analyzed as a continuous variable to evaluate depressive symptoms. Secondary outcomes included the Numeric Rating Scale (NRS) of postoperative pain, along with safety evaluations including adverse events and clinical assessments at postpartum days 14, 28, and 42. Results: A total of 298 pregnant women were included, with 150 in the control group (median age, 31.0 years [IQR, 29.0-34.0 years]) and 148 in the esketamine group (median age, 31.0 years [IQR, 28.0-34.0 years]). The prevalence of depression symptoms was significantly lower among patients given esketamine compared with controls (23.0% [34 of 148] vs 35.3% [53 of 150]; odds ratio, 0.55; 95% CI, 0.33-0.91; P = .02) on postpartum day 7. In addition, the esketamine group also showed a significantly lower change in EPDS scores (difference of least-squares means [SE], -1.17 [0.44]; 95% CI, -2.04 to -0.31; effect size, 0.74; P = .008). However, there were no differences between the groups in the incidence of positive screening results for PPD or in changes from the baseline EPDS scores at postpartum days 14, 28, and 42. There were no differences in NRS scores at rest and on movement except on movement at 72 hours postoperatively, when scores were significantly lower in the esketamine group (median, 3.0 [IQR, 2.0-3.0] vs 3.0 [IQR, 3.0-3.5]; median difference, 0 [95% CI, 0-0]; P = .03). Conclusions and Relevance: These results suggest that intravenous administration of esketamine during the perioperative period of elective cesarean delivery can improve depression symptoms during the early postpartum period. However, this antidepression effect may not be universally applicable to patients with low EPDS scores. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR2100054199.

A cuproptosis score model and prognostic score model can evaluate clinical characteristics and immune microenvironment in NSCLC.

BACKGROUND: Cuproptosis-related genes (CRGs) are associated with lung adenocarcinoma. However, the links between CRGs and non-small-cell lung cancer (NSCLC) are not clear. In this study, we aimed to develop two cuproptosis models and investigate their correlation with NSCLC in terms of clinical features and tumor microenvironment. METHODS: CRG expression profiles and clinical data from NSCLC and normal tissues was obtained from GEO (GSE42127) and TCGA datasets. Molecular clusters were classified into three patterns based on CRGs and cuproptosis cluster-related specific differentially expressed genes (CRDEGs). Then, two clinical models were established. First, a prognostic score model based on CRDEGs was established using univariate/multivariate Cox analysis. Then, through principal component analysis, a cuproptosis score model was established based on prognosis-related genes acquired via univariate analysis of CRDEGs. NSCLC patients were divided into high/low risk groups. RESULTS: Eighteen CRGs were acquired, all upregulated in tumor tissues, 15 of which significantly (P < 0.05). Among the three CRG clusters, cluster B had the best prognosis. In the CRDEG clusters, cluster C had the best survival. In the prognostic score model, the high-risk group had worse prognosis, higher tumor mutation load, and lower immune infiltration while in the cuproptosis score model, a high score represented better survival, lower tumor mutation load, and high-level immune infiltration. CONCLUSIONS: The cuproptosis score model and prognostic score model may be associated with NSCLC prognosis and immune microenvironment. These novel findings on the progression and immune landscape of NSCLC may facilitate the provision of more personalized immunotherapy interventions for NSCLC patients.

PPT1 Promotes Growth and Inhibits Ferroptosis of Oral Squamous Cell Carcinoma Cells.

BACKGROUND: Oral Squamous Cell Carcinoma (OSCC) is one of the most prevalent cancers with poor prognosis in the head and neck. Elucidating molecular mechanisms underlying OSCC occurrence and development is important for the therapy. Dysregulated palmitoylation-related enzymes have been reported in several cancers but OSCC. OBJECTIVE: To explore the role of palmitoyl protein thioesterase 1 (PPT1) in OSCC. METHODS: Differentially Expressed Genes (DEGs) and related protein-protein interaction networks between normal oral epithelial and OSCC tissues were screened and constructed via different online databases. Tumor samples from 70 OSCC patients were evaluated for the relationship between PPT1 expression level and patients'clinic characteristics. The role of PPT1 in OSCC proliferation and metastasis was studied by functional experiments, including MTT, colony formation, EdU incorporation and transwell assays. Lentivirus-based constructs were used to manipulate the gene expression. FerroOrange probe and malondialdehyde assay were used to determine ferroptosis. Growth of OSCC cells in vivo was investigated by a xenograft mouse model. RESULTS: A total of 555 DEGs were obtained, and topological analysis revealed that the PPT1 and GPX4 might play critical roles in OSCC. Increased PPT1 expression was found to be correlated with poor prognosis of OSCC patients. PPT1 effectively promoted the proliferation, migration and invasion while inhibiting the ferroptosis of OSCC cells. PPT1 affected the expression of glutathione peroxidase 4 (GPX4). CONCLUSION: PPT1 promoted growth and inhibited ferroptosis of OSCC cells. PPT1 might be a potential target for OSCC therapy.

N6-methyladenosine-modified CircPSMA7 enhances bladder cancer malignancy through the miR-128-3p/MAPK1 axis.

Several studies have indicated that circular RNAs (circRNAs) play vital roles in the progression of various diseases, including bladder cancer (BCa). However, the underlying mechanisms by which circRNAs drive BCa malignancy remain unclear. In this study, we identified a novel circRNA, circPSMA7 (circbaseID:has_circ_0003456), showing increased expression in BCa cell lines and tissues, by integrating the reported information with circRNA-seq and qRT-PCR. We revealed that circPSMA7 is associated with a higher tumor grade and stage in BCa. M6A modification was identified in circPSMA7, and IGF2BP3 recognized this modification and stabilized circPSMA7, subsequently increasing the circPSMA7 expression. In vitro and in vivo experiments showed that circPSMA7 promoted BCa proliferation and metastasis by regulating the cell cycle and EMT processes. CircPSMA7 acted as a sponge for miR-128-3p, which showed antitumor effects in BCa cell lines, increasing the expression of MAPK1. The tumor proliferation and metastasis suppression induced by silencing circPSMA7 could be partly reversed by miR-128-3p inhibition. Thus, the METTL3/IGF2BP3/circPSMA7/miR-128-3p/MAPK1 axis plays a critical role in BCa progression. Furthermore, circPSMA7 may be a potential diagnostic biomarker and novel therapeutic target for patients with BCa.

One-Component Dual-Readout Aggregation-Induced Emission Nanobeads for Qualitative and Quantitative Detection of C-Reactive Protein at the Point of Care.

Fluorescent lateral flow immunoassay (LFA) systems are versatile tools for sensitive and quantitative detection of disease markers at the point of care. However, traditional fluorescent nanoparticle-based lateral flow immunoassays are not visible under room light, necessitate an additional fluorescent reader, and lack flexibility for different application scenarios. Herein, we report a dual-readout LFA system for the rapid and sensitive detection of C-reactive protein (CRP) in clinical samples. The system relied on the aggregation-induced emission nanobeads (AIENBs) encapsulated with red AIE luminogen, which possesses both highly fluorescent and colorimetric properties. The AIENB-based LFA in the naked-eye mode was able to qualitatively detect CRP levels as low as 8.0 mg/L, while in the fluorescent mode, it was able to quantitatively measure high-sensitivity CRP (hs-CRP) with a limit of detection of 0.16 mg/L. The AIENB-based LFA system also showed a good correlation with the clinically used immunoturbidimetric method for CRP and hs-CRP detection in human plasma. This dual-modal AIENB-based LFA system offers the convenience of colorimetric testing and highly sensitive and quantitative detection of disease biomarkers and medical diagnostics in various scenarios.

An S=1 Iron(IV) Intermediate Revealed in a Non-Heme Iron Enzyme-Catalyzed Oxidative C-S Bond Formation.

Ergothioneine (ESH) and ovothiol A (OSHA) are two natural thiol-histidine derivatives. ESH has been implicated as a longevity vitamin and OSHA inhibits the proliferation of hepatocarcinoma. The key biosynthetic step of ESH and OSHA in the aerobic pathways is the O2 -dependent C-S bond formation catalyzed by non-heme iron enzymes (e.g., OvoA in ovothiol biosynthesis), but due to the lack of identification of key reactive intermediate the mechanism of this novel reaction is unresolved. In this study, we report the identification and characterization of a kinetically competent S=1 iron(IV) intermediate supported by a four-histidine ligand environment (three from the protein residues and one from the substrate) in enabling C-S bond formation in OvoA from Methyloversatilis thermotoleran, which represents the first experimentally observed intermediate spin iron(IV) species in non-heme iron enzymes. Results reported in this study thus set the stage to further dissect the mechanism of enzymatic oxidative C-S bond formation in the OSHA biosynthesis pathway. They also afford new opportunities to study the structure-function relationship of high-valent iron intermediates supported by a histidine rich ligand environment.

ADCY9 functions as a novel cancer suppressor gene in lung adenocarcinoma.

Background: The process of lucubrating into lung adenocarcinoma (LUAD) is of profound clinical and practical significance in improving the prognosis of LUAD patients. Multiple biomarkers are reportedly involved in the proliferation or metastasis of adenocarcinoma. However, whether the ADCY9 gene influences the development of LUAD remains unknown. Therefore, we aimed to elucidate the relationship between the expression of ADCY9 and the proliferation and migration of LUAD. Methods: The ADCY9 gene was filtered via a survival analysis of LUAD acquired from the Gene Expression Omnibus (GEO). Then, we conducted a validation analysis and ADCY9-microRNA, microRNA-lncRNA, and ADCY9-lncRNA targeting relationship analysis through the data obtained from The Cancer Genome Atlas (TCGA) dataset. The survival curve, correlation, and prognostic analysis were implemented through bioinformatics methods. Both protein and mRNA expression levels of LUAD cell lines and LUAD patient samples (80 pairs) were detected using western blot assays and quantitative real-time polymerase chain reaction (qRT-PCR). An immunohistochemistry assay was performed to display the correlation between the expression level of the ADCY9 gene and prognosis in LUAD patients (2012-2013; n=115). Overexpression of cell lines SPCA1 and A549 were used for a series of cell function assays. Results: Compared with the expression level in adjacent normal tissues, ADCY9 expression was downregulated in LUAD tissues. Based on the result of the survival curve analysis, high expression of ADCY9 may lead to a better prognosis and may be seen as an independent predictor for LUAD patients. High expression of ADCY9-related microRNA hsa-miR-7-5p may lead to a worse prognosis, and high expression of hsa-miR-7-5p-related lncRNAs may lead to the opposite effects. Overexpression of ADCY9 restrained the proliferation, invasion, and migration abilities of SPCA1, A549 cells. Conclusions: Results indicate that the ADCY9 gene acts as a tumor suppressor to restrain the proliferation, migration, and invasion in LUAD and can lead to a better survival or prognosis in LUAD patients.

Optimal Tracking Control of a Nonlinear Multiagent System Using Q-Learning via Event-Triggered Reinforcement Learning.

This article offers an optimal control tracking method using an event-triggered technique and the internal reinforcement Q-learning (IrQL) algorithm to address the tracking control issue of unknown nonlinear systems with multiple agents (MASs). Relying on the internal reinforcement reward (IRR) formula, a Q-learning function is calculated, and then the iteration IRQL method is developed. In contrast to mechanisms triggered by time, an event-triggered algorithm reduces the rate of transmission and computational load, since the controller may only be upgraded when the predetermined triggering circumstances are met. In addition, in order to implement the suggested system, a neutral reinforce-critic-actor (RCA) network structure is created that may assess the indices of performance and online learning of the event-triggering mechanism. This strategy is intended to be data-driven without having in-depth knowledge of system dynamics. We must develop the event-triggered weight tuning rule, which only modifies the parameters of the actor neutral network (ANN) in response to triggering cases. In addition, a Lyapunov-based convergence study of the reinforce-critic-actor neutral network (NN) is presented. Lastly, an example demonstrates the accessibility and efficiency of the suggested approach.

Novel immunogenic cell death-related risk signature to predict prognosis and immune microenvironment in lung adenocarcinoma.

PURPOSE: Immunogenic cell death (ICD) is a type of regulated cell death (RCD) which was discovered to activate adaptive immunity. To date, the effect of ICD on lung adenocarcinoma (LUAD) remains unclear. In this research, we will study the role of ICD-related genes (ICDG) in LUAD. METHODS: RNA sequencing and clinical data were gathered from TCGA-LUAD cohorts and GEO database. Using unsupervised cluster analysis, three clusters were identified with distinctive immune characteristics and significant overall survival based on 18 ICDG. Using LASSO Cox regression, three genes were identified and used to construct the prognosis signature. The association between the 3-ICDG risk signature and immune microenvironment analysis, somatic mutation, and enriched molecular pathways was investigated. RESULTS: Consensus clustering separated the LUAD samples into three clusters (ICDcluster A, B and C), and ICDcluster B had the best prognosis. Different TME cell infiltration characteristics and biological behavior were found in three ICD clusters. Prognostic risk model was contrasted based on the 3 best prognostic ICD-related genes. Subsequently, vitro experiments verified the above analysis results. The high-risk group showed a poor prognosis and enrichment of cancer promoting signal pathway. Multivariate analysis indicated that this 3-ICDG prognostic model might be an accurate prediction parameter for LUAD. Moreover, conducting immune related analysis, we found that the 3-ICDG risk signature was characterized by an immune-active subtype on account of the high infiltration of immune-active cells. CONCLUSION: This study expands our cognition of ICD in LUAD microenvironment, excavated prognostic biomarkers, and provided potential value for guiding immunotherapy and chemotherapy.

The Origin of Capsid-Derived Immune Complexes and Their Impact on HBV-Induced Liver Diseases.

Over 240 million people worldwide are chronically infected with Hepatitis B Virus (HBV), a hepatotropic DNA virus with an evolutionary root of over 400 million years. Persistent HBV infection exhibits distinct and diverse phases of disease, from minimal liver pathology to fulminant Hepatitis, that vary in duration and severity among individuals. Although huge progress has been made in HBV research which has yielded an effective prophylactic vaccine and potent antiviral therapy, our understanding of its virology and immunobiology is still far from complete. For example, the recent re-discovery of serum HBV RNA in chronic Hepatitis B (CHB) patients has led to the proposal of noncanonical viral particles such as RNA virion and capsid-derived immune complex (Capsid-Antibody-Complexes, CACs) that contradict long-established basic theory. Furthermore, the existence of capsid-derived immune complex may hint at novel mechanism of HBV-induced liver disease. Here, we summarize the past and recent literature on HBV-induced immune complex. We propose that the release of capsid-derived particles by HBV has its deep evolutionary origin, and the associated complement activation serves as an indispensable trigger for intrahepatic damage and a catalyst for further cell-mediated immunopathology.

Integration of multi-omics data reveals cis-regulatory variants that are associated with phenotypic differentiation of eastern from western pigs.

BACKGROUND: The genetic mechanisms that underlie phenotypic differentiation in breeding animals have important implications in evolutionary biology and agriculture. However, the contribution of cis-regulatory variants to pig phenotypes is poorly understood. Therefore, our aim was to elucidate the molecular mechanisms by which non-coding variants cause phenotypic differences in pigs by combining evolutionary biology analyses and functional genomics. RESULTS: We obtained a high-resolution phased chromosome-scale reference genome with a contig N50 of 18.03 Mb for the Luchuan pig breed (a representative eastern breed) and profiled potential selective sweeps in eastern and western pigs by resequencing the genomes of 234 pigs. Multi-tissue transcriptome and chromatin accessibility analyses of these regions suggest that tissue-specific selection pressure is mediated by promoters and distal cis-regulatory elements. Promoter variants that are associated with increased expression of the lysozyme (LYZ) gene in the small intestine might enhance the immunity of the gastrointestinal tract and roughage tolerance in pigs. In skeletal muscle, an enhancer-modulating single-nucleotide polymorphism that is associated with up-regulation of the expression of the troponin C1, slow skeletal and cardiac type (TNNC1) gene might increase the proportion of slow muscle fibers and affect meat quality. CONCLUSIONS: Our work sheds light on the molecular mechanisms by which non-coding variants shape phenotypic differences in pigs and provides valuable resources and novel perspectives to dissect the role of gene regulatory evolution in animal domestication and breeding.

Characteristic of Molecular Subtypes in Lung Squamous Cell Carcinoma Based on Autophagy-Related Genes and Tumor Microenvironment Infiltration.

Background: Recently, a large number of studies have sought personalized treatment for lung squamous cell carcinoma (LUSC) by dividing patients into different molecular subtypes. Autophagy plays an important role in maintaining the tumor microenvironment and immune-related biological processes. However, the molecular subtypes mediated by autophagy in LUSC are not clear. Methods: Based on 490 LUSC samples, we systematically analyzed the molecular subtype modification patterns mediated by autophagy-related genes. The ssGSEA and CIBERSORT algorithm were utilized to quantify the relative abundance of TME cell infiltration. Principal component analysis was used to construct autophagy prognostic score (APS) model. Results: We identified three autophagy subtypes in LUSC, and their clinical outcomes and TME cell infiltration had significant heterogeneity. Cluster A was rich in immune cell infiltration. The enrichment of EMT stromal pathways and immune checkpoint molecules were significantly enhanced, which may lead to its immunosuppression. Cluster B was characterized by relative immunosuppression and relative stromal activation. Cluster C was activated in biological processes related to repair. Patients with high APS were significantly positively correlated with TME stromal activity and poor survival. Meanwhile, high APS showed an advantage in response to anti-PD1 and anti-CTLA4 immunotherapy. Conclusion: This study explored the autophagy molecular subtypes in LUSC. We also discovered the heterogeneity of TME cell infiltration driven by autophagy-related genes. The established APS model is of great significance for evaluating the prognosis of LUSC patients, the infiltration of TME cells, and the effect of immunotherapy.

Single-Cell Transcriptomics Analysis of the Pathogenesis of Tendon Injury.

Tendon injury repair has been a clinical challenge, and little is known about tendon healing scar generation, repair, and regeneration mechanisms. To explore the cellular composition of tendon tissue and analyze cell populations and signaling pathways associated with tendon repair, in this paper, single-cell sequencing data was used for data mining and seven cell subsets were annotated in the tendon tissue, including fibroblasts, tenocytes, smooth muscle cells, endothelial cells, macrophages, T cells, and plasma cells. According to cell group interaction network analysis, pattern 4 composed of macrophages was an important communication pattern in tendon injury. Furthermore, the heterogeneity of M1 macrophages in tendons, the correlation of KEGG enriched pathway with inflammatory response, and the core regulatory role of the transcription factor NFKB and REL were observed; in addition, the heterogeneity of T cell isoforms in tendons was found and indicated that different isotypes of T cells involve in different roles of tendon injury and repair. This study demonstrated the heterogeneity of M1 macrophages and T cells in the tendon tissue, being involved in different physiological processes such as tendon injury and healing, providing new thinking insights and basis for subsequent clinical treatment of tendon injury.

Deciphering the Reaction Pathway of Mononuclear Iron Enzyme-Catalyzed N≡C Triple Bond Formation in Isocyanide Lipopeptide and Polyketide Biosynthesis.

Despite the diversity of reactions catalyzed by 2-oxoglutarate-dependent nonheme iron (Fe/2OG) enzymes identified in recent years, only a limited number of these enzymes have been investigated in mechanistic detail. In particular, several Fe/2OG-dependent enzymes capable of catalyzing isocyanide formation have been reported. While the glycine moiety has been identified as a biosynthon for the isocyanide group, how the actual conversion is effected remains obscure. To elucidate the catalytic mechanism, we characterized two previously unidentified (AecA and AmcA) along with two known (ScoE and SfaA) Fe/2OG-dependent enzymes that catalyze N≡C triple bond installation using synthesized substrate analogues and potential intermediates. Our results indicate that isocyanide formation likely entails a two-step sequence involving an imine intermediate that undergoes decarboxylation-assisted desaturation to yield the isocyanide product. Results obtained from the in vitro experiments are further supported by mutagenesis, the product-bound enzyme structure, and in silico analysis.

MiR-743a-5p regulates differentiation of myoblast by targeting Mob1b in skeletal muscle development and regeneration.

The microRNAs (miRNAs) play an important role in regulating myogenesis by targeting mRNA. However, the understanding of miRNAs in skeletal muscle development and diseases is unclear. In this study, we firstly performed the transcriptome profiling in differentiating C2C12 myoblast cells. Totally, we identified 187 miRNAs and 4260 mRNAs significantly differentially expressed that were involved in myoblast differentiation. We carried out validation of microarray data based on 5 mRNAs and 5 miRNAs differentially expressed and got a consistent result. Then we constructed and validated the significantly up- and down-regulated mRNA-miRNA interaction networks. Four interaction pairs (miR-145a-5p-Fscn1, miR-200c-5p-Tmigd1, miR-27a-5p-Sln and miR-743a-5p-Mob1b) with targeted relationships in differentiated myoblast cells were demonstrated. They are all closely related to myoblast development. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated cell cycle signals important for exploring skeletal muscle development and disease. Functionally, we discovered that miR-743a targeting gene Mps One Binder Kinase Activator-Like 1B (Mob1b) gene in differentiated C2C12. The up-regulated miR-743a can promote the differentiation of C2C12 myoblast. While the down-regulated Mob1b plays a negative role in differentiation. In addition, the expression profile of miR-743a and Mob1b are consistent with skeletal muscle recovery after Cardiotoxin (CTX) injury. Our study revealed that miR-743a-5p regulates myoblast differentiation by targeting Mob1b involved in skeletal muscle development and regeneration. Our findings made a further exploration for mechanisms in myogenesis and might provide potential possible miRNA-based target therapies for skeletal muscle regeneration and disease in the near future.

OvoAMtht from Methyloversatilis thermotolerans ovothiol biosynthesis is a bifunction enzyme: thiol oxygenase and sulfoxide synthase activities.

Mononuclear non-heme iron enzymes are a large class of enzymes catalyzing a wide-range of reactions. In this work, we report that a non-heme iron enzyme in Methyloversatilis thermotolerans, OvoAMtht, has two different activities, as a thiol oxygenase and a sulfoxide synthase. When cysteine is presented as the only substrate, OvoAMtht is a thiol oxygenase. In the presence of both histidine and cysteine as substrates, OvoAMtht catalyzes the oxidative coupling between histidine and cysteine (a sulfoxide synthase). Additionally, we demonstrate that both substrates and the active site iron's secondary coordination shell residues exert exquisite control over the dual activities of OvoAMtht (sulfoxide synthase vs. thiol oxygenase activities). OvoAMtht is an excellent system for future detailed mechanistic investigation on how metal ligands and secondary coordination shell residues fine-tune the iron-center electronic properties to achieve different reactivities.