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Marine photosynthetic dinoflagellates are a group of successful phytoplankton that can form red tides in the ocean and also symbiosis with corals. These features are closely related to the photosynthetic properties of dinoflagellates. We report here three structures of photosystem I (PSI)-chlorophylls (Chls) a/c-peridinin protein complex (PSI-AcpPCI) from two species of dinoflagellates by single-particle cryoelectron microscopy. The crucial PsaA/B subunits of a red tidal dinoflagellate Amphidinium carterae are remarkably smaller and hence losing over 20 pigment-binding sites, whereas its PsaD/F/I/J/L/M/R subunits are larger and coordinate some additional pigment sites compared to other eukaryotic photosynthetic organisms, which may compensate for the smaller PsaA/B subunits. Similar modifications are observed in a coral symbiotic dinoflagellate Symbiodinium species, where two additional core proteins and fewer AcpPCIs are identified in the PSI-AcpPCI supercomplex. The antenna proteins AcpPCIs in dinoflagellates developed some loops and pigment sites as a result to accommodate the changed PSI core, therefore the structures of PSI-AcpPCI supercomplex of dinoflagellates reveal an unusual protein assembly pattern. A huge pigment network comprising Chls a and c and various carotenoids is revealed from the structural analysis, which provides the basis for our deeper understanding of the energy transfer and dissipation within the PSI-AcpPCI supercomplex, as well as the evolution of photosynthetic organisms.
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Antozoários , Dinoflagellida , Animais , Antozoários/metabolismo , Complexos de Proteínas Captadores de Luz/metabolismo , Dinoflagellida/metabolismo , Proliferação Nociva de Algas , Simbiose , Microscopia Crioeletrônica , Complexo de Proteína do Fotossistema I/metabolismo , Clorofila/metabolismoRESUMO
ABSTRACT: Biallelic mutation in the DNA-damage repair gene NBN is the genetic cause of Nijmegen breakage syndrome, which is associated with predisposition to lymphoid malignancies. Heterozygous carriers of germ line NBN variants may also be at risk for leukemia development, although this is much less characterized. By sequencing 4325 pediatric patients with B-cell acute lymphoblastic leukemia (B-ALL), we systematically examined the frequency of germ line NBN variants and identified 25 unique, putatively damaging NBN coding variants in 50 patients. Compared with the frequency of NBN variants in gnomAD noncancer controls (189 unique, putatively damaging NBN coding variants in 472 of 118 479 individuals), we found significant overrepresentation in pediatric B-ALL (P = .004; odds ratio, 1.8). Most B-ALL-risk variants were missense and cluster within the NBN N-terminal domains. Using 2 functional assays, we verified 14 of 25 variants with severe loss-of-function phenotypes and thus classified these as nonfunctional or partially functional. Finally, we found that germ line NBN variant carriers, all of whom were identified as heterozygous genotypes, showed similar survival outcomes relative to those with wild type status. Taken together, our findings provide novel insights into the genetic predisposition to B-ALL, and the impact of NBN variants on protein function and suggest that heterozygous NBN variant carriers may safely receive B-ALL therapy. These trials were registered at www.clinicaltrials.gov as #NCT01225874, NCT00075725, NCT00103285, NCI-T93-0101D, and NCT00137111.
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Proteínas de Ciclo Celular , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Proteínas de Ciclo Celular/genética , Proteínas Nucleares/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genéticaRESUMO
Chromosomal aneuploidy has been associated with aging. However, whether and how chromosomal instability (CIN), a condition frequently seen in cancer cells in which chromosome missegregation occurs at a high rate, is associated with aging is not fully understood. Here, we found that primary fibroblasts isolated from aged mice (24 months old) exhibit an increased level of chromosome missegregation and micronucleation compared with that from young mice (2 months old), concomitant with an increased rate of aneuploid cells, suggesting the emergence of CIN. Reactive oxygen species were increased in fibroblasts from aged mice, which was accompanied with mitochondrial functional decline, indicating that they are under oxidative stress. Intriguingly, antioxidant treatments reduced chromosome missegregation and micronucleation rates in cells from aged mice, suggesting a link between oxidative stress and CIN. As a cause of CIN, we found that cells from aged mice are under replication stress, which was ameliorated by antioxidant treatments. Microtubule stabilization is a potential cause of CIN promoted by replication stress. Our data demonstrate the emergence of CIN with age, and suggest an unprecedented link between oxidative stress and CIN in aging.
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Mitose , Neoplasias , Camundongos , Animais , Antioxidantes/farmacologia , Segregação de Cromossomos , Instabilidade Cromossômica , Aneuploidia , Fibroblastos , Estresse Oxidativo , Neoplasias/genéticaRESUMO
Trisomy 21, the genetic cause of Down syndrome (DS), is the most common congenital chromosomal anomaly. It is associated with a 20-fold increased risk of acute lymphoblastic leukemia (ALL) during childhood and results in distinctive leukemia biology. To comprehensively define the genomic landscape of DS-ALL, we performed whole-genome sequencing and whole-transcriptome sequencing (RNA-Seq) on 295 cases. Our integrated genomic analyses identified 15 molecular subtypes of DS-ALL, with marked enrichment of CRLF2-r, IGH::IGF2BP1, and C/EBP altered (C/EBPalt) subtypes compared with 2257 non-DS-ALL cases. We observed abnormal activation of the CEBPD, CEBPA, and CEBPE genes in 10.5% of DS-ALL cases via a variety of genomic mechanisms, including chromosomal rearrangements and noncoding mutations leading to enhancer hijacking. A total of 42.3% of C/EBP-activated DS-ALL also have concomitant FLT3 point mutations or insertions/deletions, compared with 4.1% in other subtypes. CEBPD overexpression enhanced the differentiation of mouse hematopoietic progenitor cells into pro-B cells in vitro, particularly in a DS genetic background. Notably, recombination-activating gene-mediated somatic genomic abnormalities were common in DS-ALL, accounting for a median of 27.5% of structural alterations, compared with 7.7% in non-DS-ALL. Unsupervised hierarchical clustering analyses of CRLF2-rearranged DS-ALL identified substantial heterogeneity within this group, with the BCR::ABL1-like subset linked to an inferior event-free survival, even after adjusting for known clinical risk factors. These results provide important insights into the biology of DS-ALL and point to opportunities for targeted therapy and treatment individualization.
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Síndrome de Down , Leucemia-Linfoma Linfoblástico de Células Precursoras , Animais , Camundongos , Síndrome de Down/complicações , Síndrome de Down/genética , Mutação , Fatores de Risco , Genômica , Aberrações Cromossômicas , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/genéticaRESUMO
With the explosion of digital world, the dramatically increasing data volume is expected to reach 175 ZB (1 ZB = 1012 GB) in 2025. Storing such huge global data would consume tons of resources. Fortunately, it has been found that the deoxyribonucleic acid (DNA) molecule is the most compact and durable information storage medium in the world so far. Its high coding density and long-term preservation properties make itself one of the best data storage carriers for the future. High-throughput DNA synthesis is a key technology for "DNA data storage", which encodes binary data stream (0/1) into quaternary long DNA sequences consisting of four bases (A/G/C/T). In this review, the workflow of DNA data storage and the basic methods of artificial DNA synthesis technology are outlined first. Then, the technical characteristics of different synthesis methods and the state-of-the-art of representative commercial companies, with a primary focus on silicon chip microarray-based synthesis and novel enzymatic DNA synthesis are presented. Finally, the recent status of DNA storage and new opportunities for future development in the field of high-throughput, large-scale DNA synthesis technology are summarized.
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DNA , DNA/química , Armazenamento e Recuperação da Informação , Análise de Sequência com Séries de OligonucleotídeosRESUMO
The specificity and clinical relevance of cancer-associated fibroblasts (CAFs) in prostate cancer (PCa), as well as the effect of androgen deprivation therapy (ADT) on CAFs, remain to be fully elucidated. Using cell lineage diversity and weighted gene co-expression network analysis (WGCNA), we pinpointed a unique CAF signature exclusive to PCa. The specificity of this CAF signature was validated through single-cell RNA sequencing (scRNA-seq), cell line RNA sequencing, and immunohistochemistry. This signature associates CAFs with tumor progression, elevated Gleason scores, and the emergence of castration resistant prostate cancer (CRPC). Using scRNA-seq on collected samples, we demonstrated that the CAF-specific signature is not altered by ADT, maintaining its peak signal output. Identifying a PCa-specific CAF signature and observing signaling changes in CAFs after ADT lay essential groundwork for further PCa studies.
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Antagonistas de Androgênios , Fibroblastos Associados a Câncer , Progressão da Doença , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/genética , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Antagonistas de Androgênios/uso terapêutico , Antagonistas de Androgênios/farmacologia , Linhagem Celular Tumoral , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Análise de Célula Única/métodos , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/genéticaRESUMO
3-phosphoinositide-dependent protein kinase 1 (PDK1) exhibits a substantial influence on immune cell development by establishing a vital connection between PI3K and downstream mTOR signaling cascades. However, it remains unclear whether PDK1 signaling affects the homeostasis and functionality of immune cells. To explore the impact of PDK1 on different immune cells within immune organs, transgenic mouse strains with lymphocyte-specific PDK1 knockout (PDK1fl/fl CD2-Cre) were generated. Unlike wild-type (WT) mice, lymphocyte-specific PDK1 knockout (KO) mice exhibited thymic atrophy, elevated percentages of CD8+ T cells and neutrophils, and reduced proportions of γδ T cells, B cells, and NK cells in the spleen. Functional analysis revealed elevated release of IFN-γ and IL-17A by T cells in PDK1 KO mice, contrasting with diminished levels observed in γδ T cells and Treg cells. Furthermore, the activation, cytotoxicity, and migratory potential of γδ T cells in PDK1 KO mice are heightened, indicating a potential association with the regulation of the mTOR signaling pathway. To conclude, the findings of this research demonstrated that specific knockout of PDK1 in lymphocytes hindered T cell development in the thymus and exhibited a substantial influence on immune cell homeostasis in the spleen and lymph nodes.
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Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Linfócitos T CD8-Positivos , Timo , Animais , Camundongos , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Interleucina-17/metabolismo , Interleucina-17/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Baço/imunologia , Timo/imunologia , Serina-Treonina Quinases TOR/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
Transforming glycerol (GLY, biodiesel by-product) into lactic acid (LA, biodegradable polymer monomer) through sustainable electrocatalysis presents an effective strategy to reduce biodiesel production costs and consequently enhance its applications. However, current research faces a trade-off between achieving industrially-relevant current density (>300 mA cm-2) and high LA selectivity (>80%), limiting technological advancement. Herein, a Au3Ag1 alloy electrocatalyst is developed that demonstrates exceptional LA selectivity (85%) under high current density (>400 mA cm-2). The current density can further reach 1022 mA cm-2 at 1.2 V versus RHE, superior to most previous reports for GLY electrooxidation. It is revealed that the Au3Ag1 alloy can enhance GLY adsorption and reactive oxygen species (OH*) generation, thereby significantly boosting activity. As a proof of concept, a homemade flow electrolyzer is constructed, achieving remarkable LA productivity of 68.9 mmol h-1 at the anode, coupled with efficient H2 production of 3.5 L h-1 at the cathode. To further unveil the practical possibilities of this technology, crude GLY extracted from peanut oil into LA is successfully transformed, while simultaneously producing H2 at the cathode. This work showcases a sustainable method for converting biodiesel waste into high-value products and hydrogen fuel, promoting the broader application of biodiesel.
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Manganese halides are one of the most potential candidates for large-area flat-panel detection owing to their biological safety and all-solution preparation. However, reducing photon scattering and enhancing the efficient luminescence of scintillator screens remains a challenge due to their uncontrollable crystallization and serious nonradiative recombination. Herein, an organic cation modulation is reported to control the crystallization process and enhance the luminescence properties of manganese halides. Given the industrial requirements of the X-ray flat-panel detector, the large-area A2MnBr4 screen (900 cm2) with excellent uniformity is blade-coated at 60 °C. Theoretical calculations and in situ measurements reveal that organic cations with larger steric hindrance can slow down the crystallization of the screen, thus neatening the crystal arrangement and reducing the photon scattering. Moreover, larger steric hindrance can also endow the material with higher exciton binding energy, which is beneficial for restraining nonradiative recombination. Therefore, the BPP2MnBr4 (BPP = C25H22P+) screen with larger steric hindrance exhibits a superior spatial resolution (>20 lp mm-1) and ultra-low detection limit (< 250 nGyair s-1). This is the first time steric hindrance modulation is used in blade-coated scintillator screens, and it believes this study will provide some guidance for the development of high-performance manganese halide scintillators.
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RATIONALE & OBJECTIVE: Kidney stone disease (KSD), a significant health care problem within both developed and developing countries, has been associated with genetic risk factors. An association between physical activity and KSD risk also has been hypothesized, but studies have yielded inconsistent findings. This study investigated the association between the intensity of physical activity and the incidence of KSD accounting for genetic risk. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: A total of 80,473 participants from the UK Biobank Study. EXPOSURE: Physical activity levels, including total physical activity (TPA), moderate-to-vigorous intensity physical activity (MVPA), and light-intensity physical activity (LPA), were measured using accelerometers and quantified using a machine learning model. A polygenic risk score (PRS) for KSD was also constructed. OUTCOME: Individuals with KSD were identified using the International Classification of Diseases, Tenth Revision (ICD-10), and procedure codes for KSD surgery. ANALYTICAL APPROACH: A Fine and Gray survival model was used to estimate the associations of incident KSD with TPA, MVPA, LPA, and PRS (as categorical variables). Restricted cubic splines were used to examine potential nonlinear associations within the fully adjusted models. RESULTS: During an average follow-up of 6.19 years, 421 participants developed KSD. Participants in the highest quartiles of TPA, MVPA, and LPA had lower adjusted rates of KSD compared with those in the lowest quartiles: HR, 0.50 (95% CI, 0.44-0.56), 0.57 (95% CI, 0.51-0.64), and 0.66 (95% CI, 0.59-0.74), respectively. TPA, MVPA, and LPA were associated with a lower risk of KSD in participants with low and high genetic predisposition for KSD. LIMITATIONS: Selection bias as participants who provided accelerometry data may have been more adherent to health care. CONCLUSIONS: Physical activity was negatively associated with the risk of KSD, regardless of the genetic risk. Future large studies are warranted to confirm and explain the mechanisms underlying these associations. PLAIN-LANGUAGE SUMMARY: The association between the intensity of physical activity (PA) and the incidence of kidney stone disease (KSD) after accounting for genetic risk is unclear. We conducted a comprehensive prospective cohort study utilizing participants from the UK Biobank to assess the intensity of PA using accelerometers. Our study findings indicated that greater total PA, moderate-to-vigorous-intensity PA, and light-intensity PA were each associated with a lower risk of KSD irrespective of an individual's genetic risk. Our study informs the understanding of risk factors for KSD.
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Acelerometria , Bancos de Espécimes Biológicos , Exercício Físico , Predisposição Genética para Doença , Cálculos Renais , Humanos , Cálculos Renais/epidemiologia , Cálculos Renais/genética , Masculino , Feminino , Reino Unido/epidemiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso , Fatores de Risco , Incidência , Adulto , Estudos de Coortes , Medição de Risco/métodos , Biobanco do Reino UnidoRESUMO
Ultrasmall Au25(MPA)18 clusters show great potential in biocatalysts and bioimaging due to their well-defined, tunable structure and properties. Hence, in vivo pharmacokinetics and toxicity of Au nanoclusters (Au NCs) are very important for clinical translation, especially at high dosages. Herein, the in vivo hematological, tissue, and neurological effects following exposure to Au NCs (300 and 500 mg kg-1) were investigated, in which the concentration is 10 times higher than in therapeutic use. The biochemical and hematological parameters of the injected Au NCs were within normal limits, even at the ultrahigh level of 500 mg kg-1. Meanwhile, no histopathological changes were observed in the Au NC group, and immunofluorescence staining showed no obvious lesions in the major organs. Furthermore, real-time near-infrared-II (NIR-II) imaging showed that most of the Au25(MPA)18 and Au24Zn1(MPA)18 can be metabolized via the kidney. The results demonstrated that Au NCs exhibit good biosafety by evaluating the manifestation of toxic effects on major organs at ultrahigh doses, providing reliable data for their application in biomedicine.
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Ouro , Nanopartículas Metálicas , Ouro/toxicidade , Ouro/química , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/químicaRESUMO
Although acute lymphoblastic leukemia (ALL) is highly responsive to chemotherapy, it is unknown how or which host immune factors influence the long-term remission of this cancer. To this end, we systematically evaluated the effects of T-cell immunity on Ph+ ALL therapy outcomes. Using a murine Arf-/-BCR-ABL1 B-cell ALL model, we showed that loss of T cells in the host drastically increased leukemia relapse after dasatinib or cytotoxic chemotherapy. Although ABL1 mutations emerged early during dasatinib treatment in both immunocompetent and immunocompromised hosts, T-cell immunity was essential for suppressing the outgrowth of drug-resistant leukemia. Bulk and single-cell transcriptome profiling of T cells during therapy pointed to the activation of type 1 immunity-related cytokine signaling being linked to long-term leukemia remission in mice. Consistent with these observations, interferon γ and interleukin 12 directly modulated dasatinib antileukemia efficacy in vivo. Finally, we evaluated peripheral blood immune cell composition in 102 children with ALL during chemotherapy and observed a significant association of T-cell abundance with treatment outcomes. Together, these results suggest that T-cell immunity plays pivotal roles in maintaining long-term remission of ALL, highlighting that the interplay between host immunity and drug resistance can be harnessed to improve ALL chemotherapy outcomes.
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Interferon gama , Leucemia-Linfoma Linfoblástico de Células Precursoras , Animais , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Interleucina-12 , Camundongos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Inibidores de Proteínas Quinases/uso terapêutico , Linfócitos TRESUMO
Display technology is being revolutionized by cutting-edge transparent displays that can provide visual information on the screen while allowing the surrounding environment to be visible. In this report, a new method is proposed for patterning displays based on perovskite quantum dots (PQDs) on glass surfaces. A glass substrate with a polyvinylidene fluoride (PVDF) constraint layer is patterned using laser-induced plasma etching, and then a PQDs film is spin-coated on the etched sample. The PQDs pattern on the glass substrate is obtained after peeling off the PVDF constraint layer. The thickness of the film is obtained by carrying out simulations. The plasma output from different metal targets is recorded and analyzed to select the most suitable parameters and materials for improvement of the patterning accuracy. The transparent pattern display of PQDs is realized with an accuracy of 10-20 µm and a burial depth of about 1 µm. This method allows PQDs to be encapsulated under the substrate surface, which decreases the susceptibility of environmental impact. Additionally, encapsulation prevents the quantum dots from leaking out and causing environmental pollution. The proposed method has potential in the design of transparent displays and anti-counterfeiting applications.
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The combined application of metasurface and terahertz (THz) time-domain spectroscopy techniques has received considerable attention in the fields of sensing and detection. However, to detect trace samples, the THz wave must still be enhanced locally using certain methods to improve the detection sensitivity. In this study, we proposed and experimentally demonstrated a fano resonance metasurface-based silver nanoparticles (FaMs-AgNPs) sensor. AgNPs can enhance the sensitivity of the sensor by generating charge accumulation and inducing localized electric field enhancement through the tip effect, thereby enhancing the interaction between the THz waves and analytes. We investigated the effects of four different contents of AgNPs, 10 µl, 20 µl, 30 µl and 40 µl, on the detection of acetamiprid. At 30 µl of AgNPs, the amplitude change of the FaMs-AgNPs sensor was more pronounced and the sensitivity was higher, which could detect acetamiprid solutions as low as 100 pg/ml. The FaMs-AgNPs sensor has the advantages of a simple structure, easy processing, and excellent sensing performance, and has a great potential application value in the field of THz trace detection and other fields.
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Exceptional points (EPs) of non-Hermitian systems are sensitive to perturbations and facilitate the development of highly sensitive gyroscopes. We propose a compact multi-mode optical gyroscope protocol that incorporates two coupled rings and exhibits a fourth-order EP, achieving higher sensitivity compared to gyroscopes based on second-order EPs. We show that the gyroscope sensitivity can be further improved by deviating from the fourth-order EP due to the gain dependence on the cavity intensity. Furthermore, our protocol exhibits resilience against backscattering from counter-propagating modes, which leads to a reduced angular random walk (ARW) factor and increased sensitivity. These features make our protocol highly promising for advancing high-performance optical gyroscopes and enhancing angular velocity sensing technologies.
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Herein, a fiber-supported iron-based ionic liquid as a type of fibrous catalyst has been developed for the synthesis of bioactive 3,4-dihydropyrimidin-2-(1H)-ones (DHPMs) via three-component Biginelli reactions in a cleaner manner. The described fibrous catalyst was obtained from the commercially available polyetheretherketone (PEEK) fiber by postfunctionalization processes and was characterized and analyzed in detail by means of diversified technologies. Furthermore, the fiber-supported iron-based ionic liquids could mediate the classical three-component Biginelli reactions to proceed smoothly to gain a variety of substituted DHPMs with yields of up to 99%. The superior catalytic activities of the fibrous catalyst were ascribed to the quasi-homogeneous medium by ionic liquids generated in the surface layer of the PEEK fiber, which could afford an appropriate reaction zone and could further be available for the aggregation of substrates to facilitate the three-component reaction. Notably, the fibrous catalyst is available for recycling over 10 runs just by a pair of tweezers, and the operational procedure was capable of enlarging the catalytic system to the gram-scale without any performance degradation, which provided a cleaner manner to take advantage of the iron-based catalyst in organic synthesis with potential industrialization prospects.
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BACKGROUND: Mesenchymal stem cell (MSC)-derived exosomes are well recognized immunomodulating agents for cardiac repair, while the detailed mechanisms remain elusive. The Pericardial drainage pathway provides the heart with immunosurveillance and establishes a simplified model for studying the mechanisms underlying the immunomodulating effects of therapeutic exosomes. METHODS: Myocardial infarction (MI) models with and without pericardiectomy (corresponding to Tomy MI and NonTomy MI) were established to study the functions of pericardial drainage pathway in immune activation of cardiac-draining mediastinal lymph node (MLN). Using the NonTomy MI model, MSC exosomes or vehicle PBS was intrapericardially injected for MI treatment. Via cell sorting and RNA-seq (RNA-sequencing) analysis, the differentially expressed genes were acquired for integrated pathway analysis to identify responsible mechanisms. Further, through functional knockdown/inhibition studies, application of cytokines and neutralizing antibodies, western blot, flow cytometry, and cytokine array, the molecular mechanisms were studied. In addition, the therapeutic efficacy of intrapericardially injected exosomes for MI treatment was evaluated through functional and histological analyses. RESULTS: We show that the pericardial draining pathway promoted immune activation in the MLN following MI. Intrapericardially injected exosomes accumulated in the MLN and induced regulatory T cell differentiation to promote cardiac repair. Mechanistically, uptake of exosomes by major histocompatibility complex (MHC)-II+ antigen-presenting cells (APCs) induced Foxo3 activation via the protein phosphatase (PP)-2A/p-Akt/forkhead box O3 (Foxo3) pathway. Foxo3 dominated APC cytokines (IL-10, IL-33, and IL-34) expression and built up a regulatory T cell (Treg)-inducing niche in the MLN. The differentiation of Tregs as well as their cardiac deployment were elevated, which contributed to cardiac inflammation resolution and cardiac repair. CONCLUSIONS: This study reveals a novel mechanism underlying the immunomodulation effects of MSC exosomes and provides a promising candidate (PP2A/p-Akt/Foxo3 signaling pathway) with a favorable delivery route (intrapericardial injection) for cardiac repair.
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Exossomos , Traumatismos Cardíacos , Células-Tronco Mesenquimais , Infarto do Miocárdio , Humanos , Exossomos/metabolismo , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Traumatismos Cardíacos/metabolismoRESUMO
A series of asymmetric azobenzenes have been synthesized by radical-addition/ring-opening cascade reactions from 2H-indazole in the presence of PIFA and alcohols under blue light irradiation and nitrogen protection. Furthermore, a wide range of functional groups were tolerated and the corresponding products were obtained in 30% to 95% isolated yields. The protocol is characterized by its visible-light initiation, avoidance of metals and photocatalysts, mild reaction conditions, and may find potential use in materials science and medicinal chemistry.
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Electron-rich and hindered aryl chlorides are the most challenging substrates in Suzuki-Miyaura cross-coupling (SMC) reactions. Herein, we report a highly efficient catalytic system for the SMC reaction using trace amounts of commercially available catalysts [Pd(PPh3)4/(t-Bu)PCy2; Pd loading as low as 9.5 × 10-5 mol%]. This catalytic system can efficiently couple deactivated and sterically hindered aryl chlorides with various substituted phenylboronic acids, even in one-pot multiple coupling reactions (yield of products up to 92%). The impact of solvents on SMC reactions and the mechanisms of by-product formation in aryl boronic acid couplings are analyzed using density functional theory (DFT). Utilizing trace amounts of commercially available catalysts avoids complex synthesis, reduces costs, and minimizes metal residues.
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Cisplatin-based chemotherapy is the mainstay of therapeutic agents for lung cancer. Hence, we investigated the role and mechanism of circ_0006225 in tumorigenesis and cisplatin resistance in lung cancer. Levels of circ_0006225, microRNA (miR)-1236-3p and ankyrin repeat domain 22 (ANKRD22) were detected. Cell cisplatin (DDP) sensitivity and growth were determined by Cell Counting Kit-8, cell colony formation, 5-ethynyl-2'-deoxyuridine, and murine xenograft assays, respectively. A high level of circ_0006225 in lung cancer tissues and cells with cisplatin resistance was observed. Circ_0006225 deletion elevated cisplatin sensitivity and constrained proliferation in DDP-resistant lung cancer cells in vitro. Mechanistically, Circ_0006225 was confirmed to modulate ANKRD22 by sequestering miR-1236-3p. Furthermore, the suppressive effects of circ_0006225 downregulation on cisplatin resistance and proliferation in DDP-resistant lung cancer cells were reversed by miR-1236-3p inhibition or ANKRD22 overexpression. Besides that, circ_0006225 silencing also repressed cisplatin resistance and tumor growth in lung cancer in vivo. In conclusion, knockdown of circ_0006225 restrained the growth and reduced cisplatin resistance in lung cancer by the miR-1236-3p/ANKRD22 axis, suggesting a better effective therapeutic target for overcoming cisplatin resistance in lung cancer patients.