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To maintain mitochondrial homeostasis, damaged or excessive mitochondria are culled in coordination with the physiological state of the cell. The integrated stress response (ISR) is a signaling network that recognizes diverse cellular stresses, including mitochondrial dysfunction. Because the four ISR branches converge to common outputs, it is unclear whether mitochondrial stress detected by this network can regulate mitophagy, the autophagic degradation of mitochondria. Using a whole-genome screen, we show that the heme-regulated inhibitor (HRI) branch of the ISR selectively induces mitophagy. Activation of the HRI branch results in mitochondrial localization of phosphorylated eukaryotic initiation factor 2, which we show is sufficient to induce mitophagy. The HRI mitophagy pathway operates in parallel with the mitophagy pathway controlled by the Parkinson's disease related genes PINK1 and PARKIN and is mechanistically distinct. Therefore, HRI repurposes machinery that is normally used for translational initiation to trigger mitophagy in response to mitochondrial damage.
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Mitofagia , Proteínas Quinases , Mitofagia/fisiologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Autofagia/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de SinaisRESUMO
The protection of DNA replication forks under stress is essential for genome maintenance and cancer suppression. One mechanism of fork protection involves an elevation in intracellular Ca2+ ([Ca2+]i), which in turn activates CaMKK2 and AMPK to prevent uncontrolled fork processing by Exo1. How replication stress triggers [Ca2+]i elevation is unclear. Here, we report a role of cytosolic self-DNA (cytosDNA) and the ion channel TRPV2 in [Ca2+]i induction and fork protection. Replication stress leads to the generation of ssDNA and dsDNA species that, upon translocation into cytoplasm, trigger the activation of the sensor protein cGAS and the production of cGAMP. The subsequent binding of cGAMP to STING causes its dissociation from TRPV2, leading to TRPV2 derepression and Ca2+ release from the ER, which in turn activates the downstream signaling cascade to prevent fork degradation. This Ca2+-dependent genome protection pathway is also activated in response to replication stress caused by oncogene activation.
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DNA , Nucleotidiltransferases , DNA/genética , DNA/metabolismo , Replicação do DNA , DNA de Cadeia Simples , Proteínas de Membrana , Nucleotidiltransferases/metabolismo , Transdução de Sinais/fisiologia , Canais de Cátion TRPVRESUMO
The nucleolus is the most prominent membraneless condensate in the nucleus. It comprises hundreds of proteins with distinct roles in the rapid transcription of ribosomal RNA (rRNA) and efficient processing within units comprising a fibrillar centre and a dense fibrillar component and ribosome assembly in a granular component1. The precise localization of most nucleolar proteins and whether their specific localization contributes to the radial flux of pre-rRNA processing have remained unknown owing to insufficient resolution in imaging studies2-5. Therefore, how these nucleolar proteins are functionally coordinated with stepwise pre-rRNA processing requires further investigation. Here we screened 200 candidate nucleolar proteins using high-resolution live-cell microscopy and identified 12 proteins that are enriched towards the periphery of the dense fibrillar component (PDFC). Among these proteins, unhealthy ribosome biogenesis 1 (URB1) is a static, nucleolar protein that ensures 3' end pre-rRNA anchoring and folding for U8 small nucleolar RNA recognition and the subsequent removal of the 3' external transcribed spacer (ETS) at the dense fibrillar component-PDFC boundary. URB1 depletion leads to a disrupted PDFC, uncontrolled pre-rRNA movement, altered pre-rRNA conformation and retention of the 3' ETS. These aberrant 3' ETS-attached pre-rRNA intermediates activate exosome-dependent nucleolar surveillance, resulting in decreased 28S rRNA production, head malformations in zebrafish and delayed embryonic development in mice. This study provides insight into functional sub-nucleolar organization and identifies a physiologically essential step in rRNA maturation that requires the static protein URB1 in the phase-separated nucleolus.
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Nucléolo Celular , Exossomos , Precursores de RNA , Processamento Pós-Transcricional do RNA , RNA Ribossômico , Peixe-Zebra , Animais , Camundongos , Nucléolo Celular/metabolismo , Desenvolvimento Embrionário , Exossomos/metabolismo , Cabeça/anormalidades , Microscopia , Proteínas Nucleares/metabolismo , Precursores de RNA/metabolismo , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , RNA Ribossômico 28S/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismoRESUMO
The high-valent cobalt-oxo species (Co(IV)=O) is being increasingly investigated for water purification because of its high redox potential, long half-life, and antiinterference properties. However, generation of Co(IV)=O is inefficient and unsustainable. Here, a cobalt-single-atom catalyst with N/O dual coordination was synthesized by O-doping engineering. The O-doped catalyst (Co-OCN) greatly activated peroxymonosulfate (PMS) and achieved a pollutant degradation kinetic constant of 73.12 min-1 g-2, which was 4.9 times higher than that of Co-CN (catalyst without O-doping) and higher than those of most reported single-atom catalytic PMS systems. Co-OCN/PMS realized Co(IV)=O dominant oxidation of pollutants by increasing the steady-state concentration of Co(IV)=O (1.03 × 10-10 M) by 5.9 times compared with Co-CN/PMS. A competitive kinetics calculation showed that the oxidation contribution of Co(IV)=O to micropollutant degradation was 97.5% during the Co-OCN/PMS process. Density functional theory calculations showed that O-doping influenced the charge density (increased the Bader charge transfer from 0.68 to 0.85 e), optimized the electron distribution of the Co center (increased the d-band center from -1.14 to -1.06 eV), enhanced the PMS adsorption energy from -2.46 to -3.03 eV, and lowered the energy barrier for generation of the key reaction intermediate (*O*H2O) during Co(IV)=O formation from 1.12 to 0.98 eV. The Co-OCN catalyst was fabricated on carbon felt for a flow-through device, which achieved continuous and efficient removal of micropollutants (degradation efficiency of >85% after 36 h operation). This study provides a new protocol for PMS activation and pollutant elimination through single-atom catalyst heteroatom-doping and high-valent metal-oxo formation during water purification.
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MOTIVATION: The Full-text index in Minute space (FM-index) is a memory-efficient data structure widely used in bioinformatics for solving the fundamental pattern-matching task of searching for short patterns within a long reference. With the demand for short query patterns, the k-ordered concept has been proposed for FM-indexes. However, few construction algorithms in the state of the art fully exploit this idea to achieve significant speedups in the pan-genome era. RESULTS: We introduce the k-ordered Induced Suffix Sorting (kISS) for efficient construction and utilization of k-ordered FM-indexes. We present an algorithmic workflow for building k-ordered suffix arrays, incorporating two novel strategies to improve time and memory efficiency. We also demonstrate the compatibility of integrating k-ordered FM-indexes with locate operations in FMtree. Experiments show that kISS can improve the construction time, and the generated k-ordered suffix array can also be applied to FMtree without any additional in computation or memory usage. AVAILABILITY: https://github.com/jhhung/kISS. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Iron (Fe) distribution and reutilization are crucial for maintaining Fe homeostasis in plants. Here, we demonstrate that the tomato (Solanum lycopersicum) Colorless nonripening (Cnr) epimutant exhibits increased Fe retention in cell wall pectin due to an increase in pectin methylesterase (PME) activity. This ultimately leads to Fe deficiency responses even under Fe-sufficient conditions when compared to the wild type (WT). Whole-genome bisulfite sequencing revealed that modifications to cell wall-related genes, especially CG hypermethylation in the intron region of PECTIN METHYLESTERASE53 (SlPME53), are involved in the Cnr response to Fe deficiency. When this intron hypermethylation of SlPME53 was artificially induced in WT, we found that elevated SlPME53 expression was accompanied by increased PME activity and increased pectin-Fe retention. The manipulation of SlPME53, either through overexpression in WT or knockdown in Cnr, influenced levels of pectin methylesterification and accumulation of apoplast Fe in roots. Moreover, CG hypermethylation mediated by METHYLTRANSFERASE1 (SlMET1) increased SlPME53 transcript abundance, resulting in greater PME activity and higher Fe retention in cell wall pectin. Therefore, we conclude that the Cnr mutation epigenetically modulates SlPME53 expression by SlMET1-mediated CG hypermethylation, and thus the capacity of the apoplastic Fe pool, creating opportunities for genetic improvement of crop mineral nutrition.
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Hidrolases de Éster Carboxílico , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Ferro , Raízes de Plantas , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/genética , Ferro/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Metilação de DNA/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Parede Celular/metabolismo , Pectinas/metabolismoRESUMO
Advances in nanotechnology and nanomaterials have attracted considerable interest and play key roles in scientific innovations in diverse fields. In particular, increased attention has been focused on carbon-based nanomaterials exhibiting diverse extended structures and unique properties. Among these materials, zero-dimensional structures, including fullerenes, carbon nano-onions, carbon nanodiamonds, and carbon dots, possess excellent bioaffinities and superior fluorescence properties that make these structures suitable for application to environmental and biological sensing, imaging, and therapeutics. This review provides a systematic overview of the classification and structural properties, design principles and preparation methods, and optical properties and sensing applications of zero-dimensional carbon nanomaterials. Recent interesting breakthroughs in the sensitive and selective sensing and imaging of heavy metal pollutants, hazardous substances, and bioactive molecules as well as applications in information encryption, super-resolution and photoacoustic imaging, and phototherapy and nanomedicine delivery are the main focus of this review. Finally, future challenges and prospects of these materials are highlighted and envisaged. This review presents a comprehensive basis and directions for designing, developing, and applying fascinating fluorescent sensors fabricated based on zero-dimensional carbon nanomaterials for specific requirements in numerous research fields.
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Co-inhibitory immune receptors can contribute to T cell dysfunction in patients with cancer1,2. Blocking antibodies against cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1) partially reverse this effect and are becoming standard of care in an increasing number of malignancies3. However, many of the other axes by which tumours become inhospitable to T cells are not fully understood. Here we report that V-domain immunoglobulin suppressor of T cell activation (VISTA) engages and suppresses T cells selectively at acidic pH such as that found in tumour microenvironments. Multiple histidine residues along the rim of the VISTA extracellular domain mediate binding to the adhesion and co-inhibitory receptor P-selectin glycoprotein ligand-1 (PSGL-1). Antibodies engineered to selectively bind and block this interaction in acidic environments were sufficient to reverse VISTA-mediated immune suppression in vivo. These findings identify a mechanism by which VISTA may engender resistance to anti-tumour immune responses, as well as an unexpectedly determinative role for pH in immune co-receptor engagement.
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Antígenos B7/química , Antígenos B7/metabolismo , Glicoproteínas de Membrana/metabolismo , Linfócitos T/metabolismo , Animais , Anticorpos Bloqueadores/imunologia , Anticorpos Bloqueadores/farmacologia , Antígenos B7/antagonistas & inibidores , Antígenos B7/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Cristalografia por Raios X , Epitopos de Linfócito B/química , Epitopos de Linfócito B/imunologia , Feminino , Histidina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Ligantes , Masculino , Glicoproteínas de Membrana/imunologia , Camundongos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Ligação Proteica/efeitos dos fármacos , Domínios Proteicos , Linfócitos T/citologia , Linfócitos T/imunologia , Microambiente Tumoral/imunologiaRESUMO
SignificanceIon channels have evolved the ability to communicate with one another, either through protein-protein interactions, or indirectly via intermediate diffusible messenger molecules. In special cases, the channels are part of different membranes. In muscle tissue, the T-tubule membrane is in proximity to the sarcoplasmic reticulum, allowing communication between L-type calcium channels and ryanodine receptors. This process is critical for excitation-contraction coupling and requires auxiliary proteins like junctophilin (JPH). JPHs are targets for disease-associated mutations, most notably hypertrophic cardiomyopathy mutations in the JPH2 isoform. Here we provide high-resolution snapshots of JPH, both alone and in complex with a calcium channel peptide, and show how this interaction is targeted by cardiomyopathy mutations.
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Canais de Cálcio Tipo L/metabolismo , Cardiomiopatia Hipertrófica/genética , Ativação do Canal Iônico , Mutação , Isoformas de Proteínas/metabolismo , Canais de Cálcio Tipo L/química , Cristalografia por Raios X , Humanos , Conformação Proteica , Isoformas de Proteínas/químicaRESUMO
The role of RNA methylation is vital in the advancement and spread of tumors. However, its exact role in microsatellite instability in colorectal cancer (CRC) is still not fully understood. To address this gap in knowledge, this study investigated the impact of genes associated with RNA methylation on the prognosis and response to immunotherapy in individuals diagnosed with low microsatellite instability (MSI-L) or microsatellite stable (MSS) CRC. The differentially expressed genes (DEGs) in two groups of patients: those with high microsatellite instability (MSI-H) and those with MSI-L/MSS was thoroughly investigated and compared with aims of exploring the association between them and the 60 RNA methylation regulators. We employed these genes and developed an MSI-RMscore to establish a risk signature capable of forecasting patient outcomes. Furthermore, an investigation of the immunophenotypic traits was conducted encompassing patients categorized as high-risk and low-risk. By combining the MSI-RMscore and clinicopathological features, a predictive nomogram was developed, which was subsequently validated using the GEO database. Furthermore, immunohistochemistry was employed to establish the correlation between INHBB and SOWAHA and the MSI status, as well as patient prognosis. Our findings indicated that the high-risk subgroup exhibited unfavorable overall survival rates, reduced responsiveness to immune checkpoint blockers, elevated estimate scores, and increased infiltration of macrophages and fibroblasts. We also confirmed that INHBB and SOWAHA were associated with CRC patient prognosis and MSI status, as well as immunotherapy response. These findings suggest that targeting INHBB and SOWAHA could be a promising strategy to enhance patient responsiveness to immunotherapy.
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Biomarcadores Tumorais , Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Imunoterapia , Instabilidade de Microssatélites , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Prognóstico , Biomarcadores Tumorais/genética , Imunoterapia/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Nomogramas , Metilação de DNA , Metilação de RNARESUMO
Arabidopsis histone deacetylase HDA19 is required for gene expression programs of a large spectrum of plant developmental and stress-responsive pathways. How this enzyme senses cellular environment to control its activity remains unclear. In this work, we show that HDA19 is post-translationally modified by S-nitrosylation at 4 Cysteine (Cys) residues. HDA19 S-nitrosylation depends on the cellular nitric oxide level, which is enhanced under oxidative stress. We find that HDA19 is required for cellular redox homeostasis and plant tolerance to oxidative stress, which in turn stimulates its nuclear enrichment, S-nitrosylation and epigenetic functions including binding to genomic targets, histone deacetylation and gene repression. The Cys137 of the protein is involved in basal and stress-induced S-nitrosylation, and is required for HDA19 functions in developmental, stress-responsive and epigenetic controls. Together, these results indicate that S-nitrosylation regulates HDA19 activity and is a mechanism of redox-sensing for chromatin regulation of plant tolerance to stress.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Cromatina/metabolismo , Óxido Nítrico/metabolismoRESUMO
BACKGROUND: The escalating challenge of Carbapenem-resistant Klebsiella pneumoniae (CRKP) in hospital-acquired pneumonia (HAP) is closely linked to the blaNDM-1 gene. This study explores the regulatory mechanisms of blaNDM-1 expression and aims to enhance antibacterial tactics to counteract the spread and infection of resistant bacteria. METHODS: KP and CRKP strains were isolated from HAP patients' blood samples. Transcriptomic sequencing (RNA-seq) identified significant upregulation of blaNDM-1 gene expression in CRKP strains. Bioinformatics analysis revealed blaNDM-1 gene involvement in beta-lactam resistance pathways. CRISPR-Cas9 was used to delete the blaNDM-1 gene, restoring sensitivity. In vitro and in vivo experiments demonstrated enhanced efficacy with Imipenem and Thanatin or Subatan combination therapy. RESULTS: KP and CRKP strains were isolated with significant upregulation of blaNDM-1 in CRKP strains identified by RNA-seq. The Beta-lactam resistance pathway was implicated in bioinformatics analysis. Knockout of blaNDM-1 reinstated sensitivity in CRKP strains. Further, co-treatment with Imipenem, Thanatin, or Subactam markedly improved antimicrobial effectiveness. CONCLUSION: Silencing blaNDM-1 in CRKP strains from HAP patients weakens their Carbapenem resistance and optimizes antibacterial strategies. These results provide new theoretical insights and practical methods for treating resistant bacterial infections.
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Infecções por Klebsiella , Pneumonia , Humanos , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Klebsiella pneumoniae/genética , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Imipenem , Hospitais , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/genética , Infecções por Klebsiella/microbiologiaRESUMO
BACKGROUND: Indobufen is widely used in patients with aspirin intolerance in East Asia. The OPTION trial launched by our cardiac center examined the performance of indobufen based dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI). However, the vast majority of patients with acute coronary syndrome (ACS) and aspirin intolerance were excluded. We aimed to explore this question in a real-world population. METHODS: Patients enrolled in the ASPIRATION registry were grouped according to the DAPT strategy that they received after PCI. The primary endpoints were major adverse cardiovascular and cerebrovascular events (MACCE) and Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding. Propensity score matching (PSM) was adopted for confounder adjustment. RESULTS: A total of 7135 patients were reviewed. After one-year follow-up, the indobufen group was associated with the same risk of MACCE versus the aspirin group after PSM (6.5% vs. 6.5%, hazard ratio [HR] = 0.99, 95% confidence interval [CI] = 0.65 to 1.52, P = 0.978). However, BARC type 2, 3, or 5 bleeding was significantly reduced (3.0% vs. 11.9%, HR = 0.24, 95% CI = 0.15 to 0.40, P < 0.001). These results were generally consistent across different subgroups including aspirin intolerance, except that indobufen appeared to increase the risk of MACCE in patients with ACS. CONCLUSIONS: Indobufen shared the same risk of MACCE but a lower risk of bleeding after PCI versus aspirin from a real-world perspective. Due to the observational nature of the current analysis, future studies are still warranted to further evaluate the efficacy of indobufen based DAPT, especially in patients with ACS. TRIAL REGISTRATION: Chinese Clinical Trial Register ( https://www.chictr.org.cn ); Number: ChiCTR2300067274.
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Síndrome Coronariana Aguda , Isoindóis , Intervenção Coronária Percutânea , Fenilbutiratos , Humanos , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/cirurgia , Aspirina/efeitos adversos , Quimioterapia Combinada , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Inibidores da Agregação Plaquetária/efeitos adversos , Sistema de Registros , Resultado do TratamentoRESUMO
Here, we present a straightforward strategy for designing silicon grating-based metasurfaces tailored for narrow near-infrared bandpass filtering. By selecting appropriate structural parameters for the grating and including periodic groove perturbations within each grating slit, transverse guided mode resonances (GMRs) propagating perpendicular and parallel to the grating slit are created to provide wide out-of-band suppression and high-Q filter responses, respectively. The destructive and constructive interference between radiations from groove perturbations are then introduced to eliminate all GMRs except one, producing a single-band bandpass filter. Simply adjusting the period of the groove perturbations allows precise tuning of the passband's central wavelength across the operational spectral range from 1350â nm to 1750nm, throughout which the passband exhibits a Q-factor exceeding 9,000 and the attenuation level outside the passband remains below 1%. Furthermore, our proposed narrow bandpass filters are found to be robust against the potential fabrication imperfections, such as variations in groove size and position.
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Cordyceps cicadae (Hypocreales: Cordycipitaceae) is a renowned entomopathogenic fungus used as herbal medicine in China. However, wild C. cicadae resources have been threatened by heavy harvesting. We hypothesised that Bombyx mori L. (Lepidoptera: Bombycidae) could be a new alternative to cultivate C. cicadae due to the low cost of rearing. Bacterial communities are crucial for the formation of Cordyceps and for promoting the production of metabolites. To better understand the bacterial community structure associated with Cordyceps, three Claviciptaceae fungi were used to explore the pathogenicity of the silkworms. Here, fifth-instar silkworms were infected with C. cicadae, Cordyceps cateniannulata (Hypocreales: Cordycipitaceae) and Beauveria bassiana (Hypocreales: Cordycipitaceae). Subsequently, we applied high-throughput sequencing to explore the composition of bacterial communities in silkworms. Our results showed that all three fungi were highly pathogenic to silkworms, which suggests that silkworms have the potential to cultivate Cordyceps. After fungal infection, the diversity of bacterial communities in silkworms decreased significantly, and the abundance of Staphylococcus increased in mummified larvae, which may play a role in the death process when the host suffers infection by entomopathogenic fungi. Furthermore, there were high similarities in the bacterial community composition and function in the C. cicadae and C. cateniannulata infected samples, and the phylogenetic analysis suggested that these similarities may be related to the fungal phylogenetic relationship. Our findings reveal that infection with different entomopathogenic fungi affects the composition and function of bacterial communities in silkworms and that the bacterial species associated with Cordyceps are primarily host dependent, while fungal infection affects bacterial abundance.
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Background: The noninvasive computed tomography angiography-derived fractional flow reserve (CT-FFR) can be used to diagnose coronary ischemia. With advancements in associated software, the diagnostic capability of CT-FFR may have evolved. This study evaluates the effectiveness of a novel deep learning-based software in predicting coronary ischemia through CT-FFR. Methods: In this prospective study, 138 subjects with suspected or confirmed coronary artery disease were assessed. Following indication of 30%-90% stenosis on coronary computed tomography (CT) angiography, participants underwent invasive coronary angiography and fractional flow reserve (FFR) measurement. The diagnostic performance of the CT-FFR was determined using the FFR as the reference standard. Results: With a threshold of 0.80, the CT-FFR displayed an impressive diagnostic accuracy, sensitivity, specificity, area under the receiver operating characteristic curve (AUC), positive predictive value (PPV), and negative predictive value (NPV) of 97.1%, 96.2%, 97.7%, 0.98, 96.2%, and 97.7%, respectively. At a 0.75 threshold, the CT-FFR showed a diagnostic accuracy, sensitivity, specificity, AUC, PPV, and NPV of 84.1%, 78.8%, 85.7%, 0.95, 63.4%, and 92.8%, respectively. The Bland-Altman analysis revealed a direct correlation between the CT-FFR and FFR (p < 0.001), without systematic differences (p = 0.085). Conclusions: The CT-FFR, empowered by novel deep learning software, demonstrates a strong correlation with the FFR, offering high clinical diagnostic accuracy for coronary ischemia. The results underline the potential of modern computational approaches in enhancing noninvasive coronary assessment.
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Chordin like-1 (CHRDL1) is an antagonist of bone morphogenetic proteins (BMPs) that acts through binding BMPs and blocking their interaction with BMP receptors. CHRDL1 plays a role in osteoblast differentiation but controversial effects were reported. On the other hand, the role of CHRDL1 in adipogenesis is unknown. In the present study, we investigated the function of CHRDL1 in regulating differentiation of osteoblasts and adipocytes and elucidated the underlying mechanism. CHRDL1 expression was downregulated during osteogenesis while it was upregulated during adipogenesis in primary cultured and established mesenchymal progenitor cell lines. Functional experiments revealed that CHRDL1 suppressed osteoblast differentiation and promoted adipocyte differentiation. Mechanistic explorations revealed that CHRDL1 is directly bound to insulin-like growth factor binding protein 3 (IGFBP3) and attenuated the degradation of the latter. Furthermore, CHRDL1 and IGFBP3 suppressed the activity of insulin receptor substrate 1 (IRS1)/AKT serine/threonine kinase (AKT)/mechanistic target of rapamycin kinase complex 1 (mTORC1) signaling in progenitor cells undergoing osteogenic differentiation. By contrast, they activated AKT/mTORC1 signaling independently of IRS1 during adipogenic differentiation. CHRDL1 enhanced the interaction of nuclear IGFBP3 and retinoid X receptor α (RXRα) during adipogenesis, and inhibition of RXR inactivated AKT and attenuated the stimulation of adipogenic differentiation by CHRDL1. Overexpression of IGFBP3 relieved the perturbation of osteogenic and adipogenic differentiation of progenitor cells induced by CHRDL1 silencing. Finally, CHRDL1 and IGFBP3 were upregulated in the trabecular bone of aged mice. Our study provides evidence that CHRDL1 reciprocally regulates osteoblast and adipocyte differentiation through stabilizing IGFBP3 and differentially modulating AKT/mTORC1 signaling.
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Osteogênese , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Adipócitos/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/fisiologia , Proteínas do Olho/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Osteoblastos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
BACKGROUND: Neoadjuvant chemotherapy with dual-targeted therapy is the standard treatment for human epidermal growth factor 2 (HER2)-positive breast cancer. Although the dual-targeted therapy has significantly improved the pathological complete response (pCR) rate, further investigation is needed to identify biomarkers that predict the response to neoadjuvant therapy. METHODS: This retrospective study analyzed 353 patients with HER2-positive breast invasive ductal carcinoma. The correlation between clinicopathological factors and pCR rate was evaluated. A nomogram was constructed based on the results of the multivariate logistic regression analysis to predict the probability of pCR. RESULTS: The breast pCR (b-pCR) rate was 56.1% (198/353) and the total pCR (t-pCR) rate was 52.7% (186/353). Multivariate analysis identified ER status, PR status, HER2 status, Ki-67 index, and neoadjuvant chemotherapy regimens as independent indicators for both b-pCR and t-pCR. The nomogram had an area under the receiver operating characteristic curve (AUC) of 0.73 (95% CI: 0.68-0.78). According to the nomogram, the t- pCR rate was highest in the ER-PR- HER2-positive patients (131/208) and lowest in the ER + PR + HER2-positive patients (19/73). The subgroup analyses showed that there was no significant difference in pCR rate among the neoadjuvant chemotherapy regimens in ER positive, PR positive, HER2 IHC 2 + , Ki67 index < 30% population. However, for ER-PR-HER2-positive patients, the neoadjuvant chemotherapy regimen has a great influence on the pCR rates. CONCLUSIONS: Patients with ER-negative, PR-negative, HER2 3 + and high KI-67 index were more likely to achieve pCR. THP may be used as an alternative to AC-THP or TCbHP in selected HER2-positive patients.
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Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Terapia Neoadjuvante , Resultado do Tratamento , Receptor ErbB-2/metabolismo , Antígeno Ki-67 , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Chronic liver damage (CLD) encompasses a spectrum of conditions and poses a significant global health challenge, affecting millions of individuals. Currently, there is a deficiency of clinically validated therapeutics with minimal side effects. Emerging evidence underscores the significant potential of extracellular vesicles derived from bone marrow mesenchymal stem cells (BMSC-EVs) as a promising therapeutic method for CLD. This study aimed to evaluate the influence of BMSC-EVs containing microRNA-136-5p (BMSC-EVs-miR-136-5p) on macrophage polarization during chronic liver injury and elucidate the mechanisms associated with the GNAS/PI3K/ERK/STAT3 axis. Surface markers of BMSCs were detected via Immunofluorescent Staining. Subsequently, EVs were harvested from the BMSC culture medium. In vivo fluorescence imaging was employed to locate the BMSC-EVs. Additionally, fluorescence microscopy was used to visualize the uptake of DIR-labeled BMSC-EVs by RAW264.7 cells. Various methods were employed to assess the impact of BMSC-EVs on the expression levels of inflammatory factors (IL-1ß, IL-6, IL-10, and TNF-α), M1/M2 macrophage markers (iNOS and Arg-1), and members of inflammation-related signaling pathways (GNAS, PI3K, ERK, and STAT3) in RAW264.7 cells co-cultured with BMSC-EVs. Loss-of-function approaches targeting miR-136-5p in RAW264.7 cells were subsequently utilized to validate the role of BMSC-EVs-miR-136-5p. The Luciferase Reporter Assay indicates that GNAS was identified to be a target of miR-136-5p, and miR-136-5p demonstrating increased within BMSC-EVs compared to Raw264.7-EVs. BMSC-EVs-miR-136-5p mitigated CCl4-induced liver inflammation and improved liver function by Suppressing the GNAS/STAT3 Signaling. Notably, miR-136-5p suppressed lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells. BMSC-EVs-miR-136-5p alleviates CLD by activating M2 polarization through the GNAS-mediated PI3K/ERK/STAT3 axis. Accordingly, the members of this axis may serve as therapeutic targets.
RESUMO
Sperm DNA fragmentation is a sign of sperm nuclear damage. The sperm chromatin dispersion (SCD) test is a reliable and economical method for the evaluation of DNA fragmentation. However, the cut-off value for differentiation of DNA fragmented sperms is fixed at 1/3 with limited statistical justification, making the SCD test a semi-quantitative method that gives user-dependent results. We construct a collection of deep neural networks to automate the evaluation of bright-field images for SCD tests. The model can detect valid sperm nuclei and their locations from the input images captured with a 20× objective and predict the geometric parameters of the halo ring. We construct an annotated dataset consisting of N = 3120 images. The ResNet 18 based network reaches an average precision (AP50) of 91.3%, a true positive rate of 96.67%, and a true negative rate of 96.72%. The distribution of relative halo radii is fit to the multi-peak Gaussian function (p > 0.99). DNA fragmentation is regarded as those with a relative halo radius 1.6 standard deviations smaller than the mean of a normal cluster. In conclusion, we have established a deep neural network based model for the automation and quantification of the SCD test that is ready for clinical application. The DNA fragmentation index is determined using Gaussian clustering, reflecting the natural distribution of halo geometry and is more tolerable to disturbances and sample conditions, which we believe will greatly improve the clinical significance of the SCD test.