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Motor neurons are the final common pathway1 through which the brain controls movement of the body, forming the basic elements from which all movement is composed. Yet how a single motor neuron contributes to control during natural movement remains unclear. Here we anatomically and functionally characterize the individual roles of the motor neurons that control head movement in the fly, Drosophila melanogaster. Counterintuitively, we find that activity in a single motor neuron rotates the head in different directions, depending on the starting posture of the head, such that the head converges towards a pose determined by the identity of the stimulated motor neuron. A feedback model predicts that this convergent behaviour results from motor neuron drive interacting with proprioceptive feedback. We identify and genetically2 suppress a single class of proprioceptive neuron3 that changes the motor neuron-induced convergence as predicted by the feedback model. These data suggest a framework for how the brain controls movements: instead of directly generating movement in a given direction by activating a fixed set of motor neurons, the brain controls movements by adding bias to a continuing proprioceptive-motor loop.
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Drosophila melanogaster , Neurônios Motores , Movimento , Postura , Propriocepção , Animais , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Retroalimentação Fisiológica/fisiologia , Cabeça/fisiologia , Modelos Neurológicos , Neurônios Motores/fisiologia , Movimento/fisiologia , Postura/fisiologia , Propriocepção/genética , Propriocepção/fisiologia , MasculinoRESUMO
Chirality is a unifying structural metric of biological and abiological forms of matter. Over the past decade, considerable clarity has been achieved in understanding the chemistry and physics of chiral inorganic nanoparticles1-4; however, little is known about their effects on complex biochemical networks5,6. Intermolecular interactions of biological molecules and inorganic nanoparticles show some commonalities7-9, but these structures differ in scale, in geometry and in the dynamics of chiral shapes, which can both impede and strengthen their mirror-asymmetric complexes. Here we show that achiral and left- and right-handed gold biomimetic nanoparticles show different in vitro and in vivo immune responses. We use irradiation with circularly polarized light (CPL) to synthesize nanoparticles with controllable nanometre-scale chirality and optical anisotropy factors (g-factors) of up to 0.4. We find that binding of nanoparticles to two proteins from the family of adhesion G-protein-coupled receptors (AGPCRs)-namely cluster-of-differentiation 97 (CD97) and epidermal-growth-factor-like-module receptor 1 (EMR1)-results in the opening of mechanosensitive potassium-efflux channels, the production of immune signalling complexes known as inflammasomes, and the maturation of mouse bone-marrow-derived dendritic cells. Both in vivo and in vitro immune responses depend monotonically on the g-factors of the nanoparticles, indicating that nanoscale chirality can be used to regulate the maturation of immune cells. Finally, left-handed nanoparticles show substantially higher (1,258-fold) efficiency compared with their right-handed counterparts as adjuvants for vaccination against the H9N2 influenza virus, opening a path to the use of nanoscale chirality in immunology.
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Proteínas de Ligação ao Cálcio , Células Dendríticas , Inflamassomos , Nanopartículas Metálicas , Receptores Acoplados a Proteínas G , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Células Dendríticas/imunologia , Ouro , Vírus da Influenza A Subtipo H9N2 , Mecanotransdução Celular , Nanopartículas Metálicas/química , Camundongos , Canais de Potássio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , EstereoisomerismoRESUMO
Visualizing the location and dynamics of RNAs in live cells is key to understanding their function. Here, we identify two endonuclease-deficient, single-component programmable RNA-guided and RNA-targeting Cas13 RNases (dCas13s) that allow robust real-time imaging and tracking of RNAs in live cells, even when using single 20- to 27-nt-long guide RNAs. Compared to the aptamer-based MS2-MCP strategy, an optimized dCas13 system is user friendly, does not require genetic manipulation, and achieves comparable RNA-labeling efficiency. We demonstrate that the dCas13 system is capable of labeling NEAT1, SatIII, MUC4, and GCN4 RNAs and allows the study of paraspeckle-associated NEAT1 dynamics. Applying orthogonal dCas13 proteins or combining dCas13 and MS2-MCP allows dual-color imaging of RNAs in single cells. Further combination of dCas13 and dCas9 systems allows simultaneous visualization of genomic DNA and RNA transcripts in living cells.
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Imagem Molecular/métodos , RNA/fisiologia , Imagem Individual de Molécula/métodos , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Humanos , Mucina-4 , Engenharia de Proteínas/métodos , RNA Guia de Cinetoplastídeos/genética , RNA Longo não Codificante , Ribonucleases/genética , Ribonucleases/metabolismo , Coloração e Rotulagem/métodosRESUMO
Ligand-protected metal clusters possess hybrid properties that seamlessly combine an inorganic core with an organic ligand shell, imparting them exceptional chemical flexibility and unlocking remarkable application potential in diverse fields. Leveraging chemical flexibility to expand the library of available materials and stimulate the development of new functionalities is becoming an increasingly pressing requirement. This Review focuses on the origin of chemical flexibility from the structural analysis, including intra-cluster bonding, inter-cluster interactions, cluster-environments interactions, metal-to-ligand ratios, and thermodynamic effects. In the introduction, we briefly outline the development of metal clusters and explain the differences and commonalities of M(I)/M(I/0) coinage metal clusters. Additionally, we distinguish the bonding characteristics of metal atoms in the inorganic core, which give rise to their distinct chemical flexibility. Section 2 delves into the structural analysis, bonding categories, and thermodynamic theories related to metal clusters. In the following sections 3 to 7, we primarily elucidate the mechanisms that trigger chemical flexibility, the dynamic processes in transformation, the resultant alterations in structure, and the ensuing modifications in physical-chemical properties. Section 8 presents the notable applications that have emerged from utilizing metal clusters and their assemblies. Finally, in section 9, we discuss future challenges and opportunities within this area.
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SignificanceThere is a common consensus that lode gold deposits mostly precipitated from metamorphic fluids via fluid boiling and/or fluid-rock interaction, but whether magmatic hydrothermal fluids and the mixing of such fluids with an external component have played a vital role in the formation of lode gold deposits remains elusive. We use garnet secondary ion mass spectrometry oxygen isotope analysis to demonstrate that the world-class Dongping lode gold deposit has been formed by multiple pulses of magmatic hydrothermal fluids and their mixing with large volumes of meteoric water. This study opens an opportunity to tightly constrain the origin of lode gold deposits worldwide and other hydrothermal systems that may have generated giant ore deposits in the Earth's crust.
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Dysfunctional gene expression in nociceptive pathways plays a critical role in the development and maintenance of neuropathic pain. Super enhancers (SEs), composed of a large cluster of transcriptional enhancers, are emerging as new players in the regulation of gene expression. However, whether SEs participate in nociceptive responses remains unknown. Here, we report a spinal-specific SE (SS-SE) that regulates chronic constriction injury (CCI)-induced neuropathic pain by driving Ntmt1 and Prrx2 transcription in dorsal horn neurons. Peripheral nerve injury significantly enhanced the activity of SS-SE and increased the expression of NTMT1 and PRRX2 in the dorsal horn of male mice in a bromodomain-containing protein 4 (BRD4)-dependent manner. Both intrathecal administration of a pharmacological BRD4 inhibitor JQ1 and CRISPR-Cas9-mediated SE deletion abolished the increased NTMT1 and PRRX2 in CCI mice and attenuated their nociceptive hypersensitivities. Furthermore, knocking down Ntmt1 or Prrx2 with siRNA suppressed the injury-induced elevation of phosphorylated extracellular-signal-regulated kinase (p-ERK) and glial fibrillary acidic protein (GFAP) expression in the dorsal horn and alleviated neuropathic pain behaviors. Mimicking the increase in spinal Ntmt1 or Prrx2 in naive mice increased p-ERK and GFAP expression and led to the genesis of neuropathic pain-like behavior. These results redefine our understanding of the regulation of pain-related genes and demonstrate that BRD4-driven increases in SS-SE activity is responsible for the genesis of neuropathic pain through the governance of NTMT1 and PRRX2 expression in dorsal horn neurons. Our findings highlight the therapeutic potential of BRD4 inhibitors for the treatment of neuropathic pain.SIGNIFICANCE STATEMENT SEs drive gene expression by recruiting master transcription factors, cofactors, and RNA polymerase, but their role in the development of neuropathic pain remains unknown. Here, we report that the activity of an SS-SE, located upstream of the genes Ntmt1 and Prrx2, was elevated in the dorsal horn of mice with neuropathic pain. SS-SE contributes to the genesis of neuropathic pain by driving expression of Ntmt1 and Prrx2 Both inhibition of SS-SE with a pharmacological BRD4 inhibitor and genetic deletion of SS-SE attenuated pain hypersensitivities. This study suggests an effective and novel therapeutic strategy for neuropathic pain.
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Hipersensibilidade , Neuralgia , Ratos , Masculino , Camundongos , Animais , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Hiperalgesia/metabolismo , Ratos Sprague-Dawley , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neuralgia/metabolismo , Corno Dorsal da Medula Espinal/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hipersensibilidade/metabolismoRESUMO
BACKGROUND: CRISPR-Cas9 technology has advanced in vivo gene therapy for disorders like hemophilia A, notably through the successful targeted incorporation of the F8 gene into the Alb locus in hepatocytes, effectively curing this disorder in mice. However, thoroughly evaluating the safety and specificity of this therapy is essential. Our study introduces a novel methodology to analyze complex insertion sequences at the on-target edited locus, utilizing barcoded long-range PCR, CRISPR RNP-mediated deletion of unedited alleles, magnetic bead-based long amplicon enrichment, and nanopore sequencing. RESULTS: We identified the expected F8 insertions and various fragment combinations resulting from the in vivo linearization of the double-cut plasmid donor. Notably, our research is the first to document insertions exceeding ten kbp. We also found that a small proportion of these insertions were derived from sources other than donor plasmids, including Cas9-sgRNA plasmids, genomic DNA fragments, and LINE-1 elements. CONCLUSIONS: Our study presents a robust method for analyzing the complexity of on-target editing, particularly for in vivo long insertions, where donor template integration can be challenging. This work offers a new tool for quality control in gene editing outcomes and underscores the importance of detailed characterization of edited genomic sequences. Our findings have significant implications for enhancing the safety and effectiveness of CRISPR-Cas9 gene therapy in treating various disorders, including hemophilia A.
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Hemofilia A , Sequenciamento por Nanoporos , Camundongos , Animais , Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , Hemofilia A/genética , Hemofilia A/terapia , Edição de Genes/métodos , DNARESUMO
BACKGROUND: The NCCN/FACT Bladder Symptom Index-18 (NFBlSI-18) is a bladder cancer-specific instrument. We aimed to psychometrically evaluate the reliability and validity of NFBlSI-18 and estimate change thresholds for total, disease-related symptoms-physical (DRS-P), DRS-emotional (DRS-E), and function/well-being (F/WB) scales in patients with locally advanced/metastatic urothelial cancer (la/mUC). METHODS: JAVELIN Bladder 100 trial data were analyzed. Anchors to evaluate validity included: 5-level EuroQoL-5D utility index (EQ-5D-5L UI), visual analog scale (VAS), Eastern Cooperative Oncology Group (ECOG) performance status, and number of symptoms. Responsiveness to change was tested by anchoring to time to tumor progression (TTP), best overall response (BOR), and differences in means between ECOG categories to estimate meaningful between-group differences. Meaningful within-group change thresholds were estimated using receiver operating characteristic curve analysis, anchoring to change in EQ-5D-5L UI. Significant within-individual patient change thresholds were estimated with reliable and likely change indexes. RESULTS: Correlations with EQ-5D-5L UI and VAS ranged from 0.53 to 0.73. Standardized effect sizes were >0.20. Compared with patients with TTP of ≥6 months, patients with TTP of >0-2 and 3-5 months had larger declines; results for BOR were similar. Thresholds (points) for meaningful between-group differences were: total, 6-11; DRS-P, 3-6; and DRS-E and F/WB, 1. Thresholds (points) for meaningful within-group worsening were: total, 4; and DRS-P, 3, and for significant individual change they were: total, 3-9; DRS-P, 2-6; DRS-E, 1-3; and F/WB, 2-4. CONCLUSIONS: NFBlSI-18 exhibited evidence of reliability, validity, and responsiveness to assess quality of life in studies of la/mUC, and change thresholds are established for future studies. PLAIN LANGUAGE SUMMARY: The NCCN/FACT Bladder Symptom Index-18 (NFBlSI-18) is a questionnaire used to assess quality of life for people with advanced bladder cancer. People with advanced bladder cancer who took part in the JAVELIN Bladder 100 study completed the NFBlSI-18 when they joined the study and after each treatment with avelumab maintenance or best supportive care. This study showed that NFBlSI-18 is suitable for capturing bladder cancer symptoms and is able to detect important changes in a person's quality of life over time. This study also provides thresholds for changes in NFBlSI-18 scores, which will be useful for future studies.
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Qualidade de Vida , Neoplasias da Bexiga Urinária , Humanos , Qualidade de Vida/psicologia , Bexiga Urinária , Reprodutibilidade dos Testes , Neoplasias da Bexiga Urinária/diagnóstico , Curva ROC , Inquéritos e Questionários , PsicometriaRESUMO
BACKGROUND: Although DHFR gene amplification has long been known as a major mechanism for methotrexate (MTX) resistance in cancer, the early changes and detailed development of the resistance are not yet fully understood. METHODS: We performed genomic, transcriptional and proteomic analyses of human colon cancer cells with sequentially increasing levels of MTX-resistance. RESULTS: The genomic amplification evolved in three phases (pre-amplification, homogenously staining region (HSR) and extrachromosomal DNA (ecDNA)). We confirm that genomic amplification and increased expression of DHFR, with formation of HSRs and especially ecDNAs, is the major driver of resistance. However, DHFR did not play a detectable role in the early phase. In the late phase (ecDNA), increase in FAM151B protein level may also have an important role by decreasing sensitivity to MTX. In addition, although MSH3 and ZFYVE16 may be subject to different posttranscriptional regulations and therefore protein expressions are decreased in ecDNA stages compared to HSR stages, they still play important roles in MTX resistance. CONCLUSION: The study provides a detailed evolutionary trajectory of MTX-resistance and identifies new targets, especially ecDNAs, which could help to prevent drug resistance. It also presents a proof-of-principal approach which could be applied to other cancer drug resistance studies.
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Resistencia a Medicamentos Antineoplásicos , Amplificação de Genes , Metotrexato , Tetra-Hidrofolato Desidrogenase , Humanos , Metotrexato/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Antimetabólitos Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genômica/métodosRESUMO
Oxaliplatin resistance poses a significant challenge in colorectal cancer (CRC) therapy, necessitating further investigation into the underlying molecular mechanisms. This study aimed to elucidate the regulatory role of SNHG4 in oxaliplatin resistance and ferroptosis in CRC. Our findings revealed that treatment with oxaliplatin led to downregulation of SNHG4 expression in CRC cells, while resistant CRC cells exhibited higher levels of SNHG4 compared to parental cells. Silencing SNHG4 attenuated oxaliplatin resistance and reduced the expression of resistance-related proteins MRD1 and MPR1. Furthermore, induction of ferroptosis effectively diminished oxaliplatin resistance in both parental and resistant CRC cells. Notably, ferroptosis induction resulted in decreased SNHG4 expression, whereas SNHG4 overexpression suppressed ferroptosis. Through FISH, RIP, and RNA pull-down assays, we identified the cytoplasmic localization of both SNHG4 and PTEN, establishing that SNHG4 directly targets PTEN, thereby reducing mRNA stability in CRC cells. Silencing PTEN abrogated the impact of SNHG4 on oxaliplatin resistance and ferroptosis in CRC cells. In vivo experiments further validated the influence of SNHG4 on oxaliplatin resistance and ferroptosis in CRC cells through PTEN regulation. In conclusion, SNHG4 promotes resistance to oxaliplatin in CRC cells by suppressing ferroptosis through instability of PTEN, thus serves as a target for patients with oxaliplatin-base chemoresistance.
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Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , Ferroptose , Oxaliplatina , PTEN Fosfo-Hidrolase , Animais , Humanos , Camundongos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos Nus , Oxaliplatina/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , MasculinoRESUMO
The combination of bedaquiline, pretomanid, and linezolid (BPaL) has become a preferred regimen for treating multidrug- and extensively drug-resistant tuberculosis (TB). However, treatment-limiting toxicities of linezolid and reports of emerging bedaquiline and pretomanid resistance necessitate efforts to develop new short-course oral regimens. We recently found that the addition of GSK2556286 increases the bactericidal and sterilizing activity of BPa-containing regimens in a well-established BALB/c mouse model of tuberculosis. Here, we used this model to evaluate the potential of new regimens combining bedaquiline or the more potent diarylquinoline TBAJ-587 with GSK2556286 and the DprE1 inhibitor TBA-7371, all of which are currently in early-phase clinical trials. We found the combination of bedaquiline, GSK2556286, and TBA-7371 to be more active than the first-line regimen and nearly as effective as BPaL in terms of bactericidal and sterilizing activity. In addition, we found that GSK2556286 and TBA-7371 were as effective as pretomanid and the novel oxazolidinone TBI-223 when either drug pair was combined with TBAJ-587 and that the addition of GSK2556286 increased the bactericidal activity of the TBAJ-587, pretomanid, and TBI-223 combination. We conclude that GSK2556286 and TBA-7371 have the potential to replace pretomanid, an oxazolidinone, or both components, in combination with bedaquiline or TBAJ-587.
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Mycobacterium tuberculosis , Nitroimidazóis , Oxazolidinonas , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Animais , Camundongos , Diarilquinolinas/farmacologia , Diarilquinolinas/uso terapêutico , Antituberculosos/uso terapêutico , Antituberculosos/farmacologia , Linezolida/farmacologia , Linezolida/uso terapêutico , Tuberculose/tratamento farmacológico , Nitroimidazóis/farmacologia , Oxazolidinonas/farmacologia , Oxazolidinonas/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológicoRESUMO
Idiopathic multicentric Castleman disease (iMCD) is subclassified into iMCD-thrombocytopenia, anasarca, reticulin fibrosis, renal dysfunction, organomegaly (TAFRO) and iMCD-not otherwise specified (NOS) according to the Castleman Disease Collaborative Network (CDCN) consensus criteria. With a deeper understanding of iMCD, a group of patients with iMCD-NOS characterised by polyclonal hypergammaglobulinaemia, plasmacytic/mixed-type lymph node histopathology and thrombocytosis has attracted attention. This group of patients has been previously described as having idiopathic plasmacytic lymphadenopathy (IPL). Whether these patients should be excluded from the current classification system lacks sufficient evidence. This retrospective analysis of 228 patients with iMCD-NOS identified 103 (45.2%) patients with iMCD-IPL. The clinical features and outcomes of patients with iMCD-IPL and iMCD-NOS without IPL were compared. Patients with iMCD-IPL showed a significantly higher inflammatory state but longer overall survival. No significant difference in overall survival was observed between severe and non-severe patients in the iMCD-IPL group according to the CDCN severity classification. Compared with lymphoma-like treatments, multiple myeloma-like and IL-6-blocking treatment approaches in the iMCD-IPL group resulted in significantly higher response rates and longer time to the next treatment. These findings highlight the particularities of iMCD-IPL and suggest that it should be considered a new subtype of iMCD-NOS.
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Hiperplasia do Linfonodo Gigante , Linfadenopatia , Humanos , Hiperplasia do Linfonodo Gigante/patologia , Hiperplasia do Linfonodo Gigante/mortalidade , Hiperplasia do Linfonodo Gigante/classificação , Hiperplasia do Linfonodo Gigante/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Idoso , Linfadenopatia/patologia , Linfadenopatia/etiologia , Plasmócitos/patologiaRESUMO
BACKGROUND & AIMS: This study assessed the worldwide burden of digestive diseases between 1990 and 2019. METHODS: We analyzed data from the Global Burden of Diseases study, covering 18 digestive diseases across 204 countries and territories. Key disease burden indicators, including incidence, prevalence, mortality, and disability-adjusted life years (DALYs), were studied. Linear regression analysis was applied to the natural logarithm of age-standardized outcomes to determine the annual percent change. RESULTS: In 2019, there were 7.32 billion incidents and 2.86 billion prevalent cases of digestive diseases, resulting in 8 million deaths and 277 million DALYs lost. Little to no decrease in global age-standardized incidence and prevalence of digestive diseases was observed between 1990 and 2019, with 95,582 and 35,106 cases per 100,000 individuals in 2019, respectively. The age-standardized death rate was 102 per 100,000 individuals. Digestive diseases accounted for a significant portion of the overall disease burden, with more than one-third of prevalent cases having a digestive etiology. Enteric infections were the primary contributor to incidence, death, and DALYs lost, whereas cirrhosis and other chronic liver diseases had the highest prevalence rate. The burden of digestive diseases was inversely related to the sociodemographic index, with enteric infections being the predominant cause of death in low and low-middle quintiles and colorectal cancer in the high quintile. CONCLUSIONS: Despite significant reductions in deaths and DALYs due to digestive diseases from 1990 to 2019, they remain prevalent. A significant disparity in the burden of digestive diseases exists among countries with different development levels.
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Efeitos Psicossociais da Doença , Carga Global da Doença , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Cirrose Hepática , Saúde Global , Incidência , Fatores de RiscoRESUMO
The production and expansion of intermediate progenitors (IPs) are essential for neocortical neurogenesis during development and over evolution. Here, we have characterized an epigenetic circuit that precisely controls neurogenic programs, particularly properties of IPs, during neocortical development. The circuit comprises a long non-coding RNA (LncBAR) and the BAF (SWI/SNF) chromatin-remodeling complex, which transcriptionally maintains the expression of Zbtb20. LncBAR knockout neocortex contains more deep-layer but fewer upper-layer projection neurons. Intriguingly, loss of LncBAR promotes IP production, but paradoxically prolongs the duration of the cell cycle of IPs during mid-later neocortical neurogenesis. Moreover, in LncBAR knockout mice, depletion of the neural progenitor pool at embryonic stage results in fewer adult neural progenitor cells in the subventricular zone of lateral ventricles, leading to a failure in adult neurogenesis to replenish the olfactory bulb. LncBAR binds to BRG1, the core enzymatic component of the BAF chromatin-remodeling complex. LncBAR depletion enhances association of BRG1 with the genomic locus of, and suppresses the expression of, Zbtb20, a transcription factor gene known to regulate both embryonic and adult neurogenesis. ZBTB20 overexpression in LncBAR-knockout neural precursors reverses compromised cell cycle progressions of IPs.
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Montagem e Desmontagem da Cromatina/genética , Neurogênese/genética , RNA Longo não Codificante/genética , Fatores de Transcrição/genética , Animais , Ciclo Celular/genética , Desenvolvimento Embrionário/genética , Epigênese Genética/genética , Camundongos , Camundongos Knockout , Neocórtex/crescimento & desenvolvimento , Neocórtex/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismoRESUMO
We show herein that 1,10-dicyano substitution restricts the paragon fluxionality of bullvalene to just 14 isomers which isomerize along a single cycle. The restricted fluxionality of 1,10-dicyanobullvalene (DCB) is investigated by means of: (i) Bonding analyses of the isomer structures using the adaptive natural density partitioning (AdNDP). (ii) Quantum dynamical simulations of the isomerizations along the cyclic intrinsic reaction coordinate of the potential energy surface (PES). The PES possesses 14 equivalent potential wells supporting 14 isomers which are separated by 14 equivalent potential barriers supporting 14 transition states. Accordingly, at low temperatures, DCB appears as a hindered molecular rotor, without any delocalization of the wavefunction in the 14 potential wells, without any nuclear spin isomers, and with completely negligible tunneling. These results are compared and found to differ from those for molecular boron rotors. (iii) Born-Oppenheimer molecular dynamics (BOMD) simulations of thermally activated isomerizations. (iv) Calculations of the rate constants in the frame of transition state theory (TST) with reasonable agreement achieved with the BOMD results. (v) Simulations of the equilibration dynamics using rate equations for the isomerizations with TST rate coefficients. Accordingly, in the long-time limit, isomerizations of the 14 isomers, each with Cs symmetry, approach the "14 Cs â C7v" thermally averaged structure. This is a superposition of the 14 equally populated isomer structures with an overall C7v symmetry. By extrapolation, the results for DCB yield working hypotheses for so far un-explored properties e.g. for the equilibration dynamics of C10H10.
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Using full configuration interaction (FCI) and multi-reference configuration interaction methods (MRCI), reliable geometrical and energetic references for Bn (n = 1-4) clusters were established. The accuracy of the computed results was confirmed by comparison with available experimental data. Benchmark calculations indicated that B97D3, B97D, VSXC, HCTH407, BP86 and CCSD(T) methods provided reasonable results for structural parameters, with mean absolute error (MAEs) within 0.020 Å. Among the tested density functional theory (DFT) methods, the VSXC functional showed the best performance in predicting the relative energies of B1 B4 with a MAE of 12.8 kJ mol-1 . Besides, B1B95, B971, TPSS, B3LYP, and BLYP functionals exhibited reasonable performance with MAE values of less than 15.0 kJ mol-1 . T1 diagnostic values between 0.035 and 0.109 at the CCSD(T) level revealed strong correlations in B2 B4 clusters, highlighting the need for caution in using CCSD(T) as an energy reference for small boron clusters. The methods of CCSDT, CCSDT(Q) and CCSDT[Q], which incorporate three-electron and four-electron excitations, effectively improved the accuracy of the energy calculations.
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BACKGROUND: Dimethyl fumarate (DMF) is a fumaric acid ester that exhibits immunoregulatory and anti-inflammatory properties. However, the function of DMF in autoimmune uveitis (AU) is incompletely understood, and studies comprehensively exploring the impact of DMF on immune cells are still lacking. METHODS: To explore the function of DMF in uveitis and its underlying mechanisms, we conducted single-cell RNA sequencing (scRNA-seq) on the cervical draining lymph node (CDLN) cells of normal, experimental autoimmune uveitis (EAU), and DMF-treated EAU mice. Additionally, we integrated scRNA-seq data of the retina and CDLNs to identify the potential impact of DMF on ocular immune cell infiltration. Flow cytometry was conducted to verify the potential target molecules of DMF. RESULTS: Our study showed that DMF treatment effectively ameliorated EAU symptoms. The proportional and transcriptional alterations in each immune cell type during EAU were reversed by DMF treatment. Bioinformatics analysis in our study indicated that the enhanced expression of Pim1 and Cxcr4 in EAU was reversed by DMF treatment. Further experiments demonstrated that DMF restored the balance between effector T (Teff) /regulatory T (Treg) cells through inhibiting the pathway of PIM1-protein kinase B (AKT)-Forkhead box O1 (FOXO1). By incorporating the scRNA-seq data of the retina from EAU mice into analysis, our study identified that T cells highly expressing Pim1 and Cxcr4 were enriched in the retina. DMF repressed the ocular infiltration of Teff cells, and this effect might depend on its inhibition of PIM1 and CXCR4 expression. Additionally, our study indicated that DMF might reduce the proportion of plasma cells by inhibiting PIM1 expression in B cells. CONCLUSIONS: DMF effectively attenuated EAU symptoms. During EAU, DMF reversed the Teff/Treg cell imbalance and suppressed the ocular infiltration of Teff cells by inhibiting PIM1 and CXCR4 expression. Thus, DMF may act as a new drug option for the treatment of AU.
Assuntos
Anti-Inflamatórios não Esteroides , Doenças Autoimunes , Fumarato de Dimetilo , Imunossupressores , Retina , Uveíte , Fumarato de Dimetilo/administração & dosagem , Fumarato de Dimetilo/farmacologia , Uveíte/genética , Uveíte/imunologia , Uveíte/terapia , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Análise da Expressão Gênica de Célula Única , Modelos Animais de Doenças , Animais , Camundongos , Feminino , Camundongos Endogâmicos C57BL , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Proteínas Proto-Oncogênicas c-pim-1/genética , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Transcrição Gênica , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Atlas como Assunto , Imunossupressores/administração & dosagem , Imunossupressores/farmacologia , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacologia , Retina/efeitos dos fármacos , Retina/imunologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologiaRESUMO
Nanomaterials with biomimetic catalytic abilities have attracted significant attention. However, the stereoselectivity of natural enzymes determined by their unique configurations is difficult to imitate. In this work, a kind of chiral CuxCoyS-CuzS nanoflowers (L/D-Pen-NFs) is developed, using porous CuxCoyS nanoparticles (NPs) as stamens, CuzS sheets as petals, and chiral penicillamine as surface stabilizers. Compared to the natural laccase enzyme, L/D-Pen-NFs exhibit significant advantages in catalytic efficiency, stability against harsh environments, recyclability, and convenience in construction. Most importantly, they display high enantioselectivity toward chiral neurotransmitters, which is proved by L- and D-Pen-NFs' different catalytic efficiencies toward chiral enantiomers. L-Pen-NFs are more efficient in catalyzing the oxidation of L-epinephrine and L-dopamine compared with D-Pen-NFs. However, their catalytic efficiency in oxidizing L-norepinephrine and L-DOPA is lower than that of D-Pen-NFs. The reason for the difference in catalytic efficiency is the distinct binding affinities between CuxCoyS-CuzS nano-enantiomers and chiral molecules. This work can spur the development of chiral nanostructures with biomimetic functions.
Assuntos
Cobre , Catálise , Cobre/química , Estereoisomerismo , Nanoestruturas/química , Biomimética/métodos , Oxirredução , Lacase/química , Lacase/metabolismoRESUMO
Diabetic wounds pose a persistent challenge due to their slow healing nature, primarily caused by bacterial infection and excessive reactive oxygen species (ROS)-induced inflammation. In this study, carbon dots with synergistic antibacterial and antioxidant properties, referred to as AA-CDs, are developed specifically for diabetic wound healing using a straightforward solvothermal method. By utilizing cost-effective precursors like citric acid and ascorbic acid, AA-CDs are engineered to possess tailored functions of photothermal sterilization and ROS scavenging. The resulting AA-CDs demonstrats broad-spectrum antibacterial activity, particularly against multidrug-resistant strains, along with efficient ROS scavenging both in solution and within cells. Additionally, AA-CDs exhibits a protective effect against oxidative stress-induced damage. Notably, with a high photothermal conversion efficiency (41.18%), AA-CDs displays heat-enhanced antioxidant performance, providing not only augmented ROS scavenging but also additional protection against oxidative stress, yielding a true "1 + 1 > 2" effect. To facilitate their use in vivo, AA-CDs are incorporated into a thermally responsive hydrogel, which exhibits evident anti-inflammatory properties by modulating inflammatory factors and significantly promots the healing of diabetic wounds. This study underscores the value of integrated platforms for diabetic wound healing and highlights the potential of versatile CDs as promising therapeutic agents in biomedical applications.
RESUMO
Autoimmune uveitis (AU) is a severe disorder causing poor vision and blindness. However, the cellular dynamics and pathogenic mechanisms underlying retinal injury in uveitis remain unclear. In this study, single-cell RNA sequencing of the retina and cervical draining lymph nodes in experimental autoimmune uveitis mice was conducted to identify the cellular spatiotemporal dynamics and upregulation of the glycolysis-related gene LDHA. Suppression of LDHA can rescue the imbalance of T effector (Teff) cells/T regulator (Treg) cells under inflammation via downregulation of the glycolysis-PI3K signaling circuit and inhibition of the migration of CXCR4+ Teff cells towards retinal tissue. Furthermore, LDHA and CXCR4 are upregulated in the peripheral blood mononuclear cells of Vogt-Koyanagi-Harada patients. The LDHA inhibitor suppresses CD4+ T cell proliferation in humans. Therefore, our data indicate that the autoimmune environment of uveitis regulates Teff cell accumulation in the retina via glycolysis-associated LDHA. Modulation of this target may provide a novel therapeutic strategy for treating AU.