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The cGAS-STING pathway plays an important role in host defense by sensing pathogen DNA, inducing type I IFNs, and initiating autophagy. However, the molecular mechanism of autophagosome formation in cGAS-STING pathway-induced autophagy is still unclear. Here, we report that STING directly interacts with WIPI2, which is the key protein for LC3 lipidation in autophagy. Binding to WIPI2 is necessary for STING-induced autophagosome formation but does not affect STING activation and intracellular trafficking. In addition, the specific interaction between STING and the PI3P-binding motif of WIPI2 leads to the competition of WIPI2 binding between STING and PI3P, and mutual inhibition between STING-induced autophagy and canonical PI3P-dependent autophagy. Furthermore, we show that the STING-WIPI2 interaction is required for the clearance of cytoplasmic DNA and the attenuation of cGAS-STING signaling. Thus, the direct interaction between STING and WIPI2 enables STING to bypass the canonical upstream machinery to induce LC3 lipidation and autophagosome formation.
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Autofagossomos , Autofagia , Proteínas de Membrana , Autofagossomos/metabolismo , Autofagia/fisiologia , DNA/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , HumanosRESUMO
BIG/DARK OVEREXPRESSION OF CAB1/TRANSPORT INHIBITOR RESPONSE3 is a 0.5-MDa protein associated with multiple functions in Arabidopsis (Arabidopsis thaliana) signalling and development. However, the biochemical functions of BIG are unknown. We investigated a role for BIG in the Arg/N-degron pathways, in which substrate protein fate is influenced by the N-terminal (Nt) residue. We crossed a big loss-of-function allele to two N-degron pathway E3 ligase mutants, proteolysis6 (prt6) and prt1, and examined the stability of protein substrates. Stability of model substrates was enhanced in prt6-1 big-2 and prt1-1 big-2 relative to the respective single mutants and the abundance of the PRT6 physiological substrates, HYPOXIA-RESPONSIVE ERF2 (HRE2) and VERNALIZATION2 (VRN2) was similarly increased in prt6 big double mutants. Hypoxia marker expression was enhanced in prt6 big double mutants; this constitutive response required arginyltransferase activity and RAP-type ERFVII transcription factors. Transcriptomic analysis of roots not only demonstrated increased expression of multiple hypoxia-responsive genes in the double mutant relative to prt6, but also revealed other roles for PRT6 and BIG, including regulation of suberin deposition through both ERFVII-dependent and independent mechanisms, respectively. Our results show that BIG acts together with PRT6 to regulate the hypoxia response and broader processes in Arabidopsis.
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Proteolysis, including post-translational proteolytic processing as well as protein degradation and amino acid recycling, is an essential component of the growth and development of living organisms. In this article, experts in plant proteolysis pose and discuss compelling open questions in their areas of research. Topics covered include the role of proteolysis in the cell cycle, DNA damage response, mitochondrial function, the generation of N-terminal signals (degrons) that mark many proteins for degradation (N-terminal acetylation, the Arg/N-degron pathway, and the chloroplast N-degron pathway), developmental and metabolic signaling (photomorphogenesis, abscisic acid and strigolactone signaling, sugar metabolism, and post-harvest regulation), plant responses to environmental signals (endoplasmic-reticulum associated degradation, chloroplast-associated degradation, drought tolerance, the growth-defense tradeoff)), and the functional diversification of peptidases. We hope these thought-provoking discussions help to stimulate further research.
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In plants, where cells cannot migrate, asymmetric cell divisions (ACDs) must be confined to the appropriate spatial context. We investigate tissue-generating asymmetric divisions in a stem cell daughter within the Arabidopsis root. Spatial restriction of these divisions requires physical binding of the stem cell regulator SCARECROW (SCR) by the RETINOBLASTOMA-RELATED (RBR) protein. In the stem cell niche, SCR activity is counteracted by phosphorylation of RBR through a cyclinD6;1-CDK complex. This cyclin is itself under transcriptional control of SCR and its partner SHORT ROOT (SHR), creating a robust bistable circuit with either high or low SHR-SCR complex activity. Auxin biases this circuit by promoting CYCD6;1 transcription. Mathematical modeling shows that ACDs are only switched on after integration of radial and longitudinal information, determined by SHR and auxin distribution, respectively. Coupling of cell-cycle progression to protein degradation resets the circuit, resulting in a "flip flop" that constrains asymmetric cell division to the stem cell region.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/citologia , Arabidopsis/metabolismo , Raízes de Plantas/citologia , Sequência de Aminoácidos , Divisão Celular Assimétrica , Ciclina D/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Ácidos Indolacéticos/metabolismo , Células do Mesofilo/metabolismo , Dados de Sequência Molecular , Fosforilação , Raízes de Plantas/metabolismo , Alinhamento de SequênciaRESUMO
Accurate chromosome segregation during meiosis requires the establishment of at least one crossover (CO) between each pair of homologous chromosomes. CO formation depends on a group of conserved pro-CO proteins, which colocalize at CO-designated sites during late meiotic prophase I. However, it remains unclear whether these pro-CO proteins form a functional complex and how they promote meiotic CO formation in vivo. Here, we show that COSA-1, a key component required for CO formation, interacts with other pro-CO factors, MSH-5 and ZHP-3, via its N-terminal disordered region. Point mutations that impair these interactions do not affect CO designation, but they strongly hinder the accumulation of COSA-1 at CO-designated sites and result in defective CO formation. These defects can be partially bypassed by artificially tethering an interaction-compromised COSA-1 derivate to ZHP-3. Furthermore, we revealed that the accumulation of COSA-1 into distinct foci is required to assemble functional 'recombination nodules'. These prevent early CO-designated recombination intermediates from being dismantled by the RTEL-1 helicase and protect late recombination intermediates, such as Holliday junctions, until they are resolved by CO-specific resolvases. Altogether, our findings provide insight into COSA-1 mediated pro-CO complex assembly and its contribution to CO formation.
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Proteínas de Caenorhabditis elegans , Troca Genética , Proteínas de Ligação a DNA , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Segregação de Cromossomos , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Meiose/genéticaRESUMO
CD137 is mainly a costimulatory receptor of CD8+ T cells. Two representative CD137 antibodies, utomilumab, and urelumab, show different costimulatory capacities in clinical trials. Balancing the antitumor effect and systemic toxicity of T cells activated by CD137 signaling is a challenge that requires clinical consideration. In this study, a panel of specific anti-human CD137 monoclonal antibodies (mAbs) were prepared and their affinities, isotypes, CD137-CRD (cysteine-rich domain) binding regions, cross-reactivity to mouse and rhesus CD137, inhibition of ligand-receptor binding and costimulatory activities were analyzed. The results showed that anti-human CD137 mAbs had high cross-reactivity with rhesus CD137. MAbs fell into three clusters according to their different binding regions of the CD137 extracellular domain. They bound to CRDI+CRDII, CRDIII or CRDIV+STP. CRDIII-binding mAbs had the strongest blocking activity. Highly costimulatory CD137 mAbs showed stronger abilities to promote CD8+ T-cell proliferation. However, the costimulatory capacity of mAbs on T cells was not closely related to their ability to block CD137L-CD137 binding and may be controlled by more elaborate CRD conformational structures. This study provides additional information for the development of next-generation CD137 mAbs to meet clinical needs.
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Comunicação Celular , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral , Camundongos , Animais , Ligantes , Transdução de Sinais , Anticorpos Monoclonais , Linfócitos T CD8-PositivosRESUMO
PURPOSE: Neoadjuvant PD-1 blockade combined with chemotherapy is a promising treatment for resectable non-small cell lung cancer (NSCLC), yet the immunological mechanisms contributing to tumor regression and biomarkers corresponding to different pathological responses remain unclear. METHODS: Using dynamic and paired blood samples from NSCLC patients receiving neoadjuvant chemoimmunotherapy, we analyzed the frequencies of CD8 + T-cell and Treg subsets and their dynamic changes during neoadjuvant treatment through flow cytometry. Cytokine profiles and function-related gene expression of CD8 + T cells and Tregs were analyzed through flow cytometry and mRNA-seq. Infiltrating T-cell subsets in resected tissues from patients with different pathological responses were analyzed through multiplex immunofluorescence. RESULTS: Forty-two NSCLC patients receiving neoadjuvant chemoimmunotherapy were enrolled and then underwent surgical resection and pathological evaluation. Nineteen patients had pCR (45%), 7 patients had MPR (17%), and 16 patients had non-MPR (38%). In patients with pCR, the frequencies of CD137 + CD8 + T cells (P = 0.0475), PD-1 + Ki-67 + CD8 + T cells (P = 0.0261) and Tregs (P = 0.0317) were significantly different from those of non-pCR patients before treatment. pCR patients usually had low frequencies of CD137 + CD8 + T cells, PD-1 + Ki-67 + CD8 + T cells and Tregs, and their AUCs were higher than that of tissue PD-L1 expression. Neoadjuvant chemoimmunotherapy markedly improved CD8 + T-cell proliferation and activation, especially in pCR patients, as the frequencies of CD137 + CD8 + (P = 0.0136) and Ki-67 + CD8 + (P = 0.0391) T cells were significantly increased. The blood levels of cytokines such as IL-2 (P = 0.0391) and CXCL10 (P = 0.0195) were also significantly increased in the pCR group, which is consistent with the high density of activated cytotoxic T cells at the tumor site (P < 0.0001). CONCLUSION: Neoadjuvant chemoimmunotherapy drives CD8 + T cells toward a proliferative and active profile. The frequencies of CD137 + CD8 + T cells, PD-1 + Ki-67 + CD8 + T cells and Tregs at baseline might predict the response to neoadjuvant chemoimmunotherapy in NSCLC patients. The increase in IL-2 and CXCL10 might reflect the chemotaxis and enrichment of cytotoxic T cells at the tumor site and a better response to neoadjuvant chemoimmunotherapy.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Terapia Neoadjuvante , Citocinas , Interleucina-2 , Antígeno Ki-67 , Receptor de Morte Celular Programada 1 , Neoplasias Pulmonares/tratamento farmacológico , Subpopulações de Linfócitos TRESUMO
The circadian oscillator allows organisms to synchronize their cellular and physiological activities with diurnal environmental changes. In plants, the circadian clock is primarily composed of multiple transcriptional-translational feedback loops. Regulators of post-transcriptional events, such as precursor messenger RNAs (pre-mRNA) splicing factors, are also involved in controlling the pace of the clock. However, in most cases the underlying mechanisms remain unclear. We have previously identified XAP5 CIRCADIAN TIMEKEEPER (XCT) as an Arabidopsis thaliana circadian clock regulator with uncharacterized molecular functions. Here, we report that XCT physically interacts with components of the spliceosome, including members of the Nineteen Complex (NTC). PacBio Iso-Seq data show that xct mutants have transcriptome-wide pre-mRNA splicing defects, predominantly aberrant 3' splice site selection. Expression of a genomic copy of XCT fully rescues those splicing defects, demonstrating that functional XCT is important for splicing. Dawn-expressed genes are significantly enriched among those aberrantly spliced in xct mutants, suggesting that the splicing activity of XCT may be circadian regulated. Furthermore, we show that loss-of-function mutations in PRP19A or PRP19B, 2 homologous core NTC components, suppress the short circadian period phenotype of xct-2. However, we do not see rescue of the splicing defects of core clock genes in prp19 xct mutants. Therefore, our results suggest that XCT may regulate splicing and the clock function through genetically separable pathways.
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Proteínas de Arabidopsis , Arabidopsis , Relógios Circadianos , Relógios Circadianos/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Precursores de RNA/genética , Splicing de RNA/genética , Arabidopsis/metabolismo , Ritmo Circadiano/genética , Regulação da Expressão Gênica de PlantasRESUMO
BACKGROUND: Little is known about the association between stroke and imaging and clinical features in conservatively treated patients with moyamoya disease (MMD). PURPOSE: To investigate independent risk factors for stroke in conservatively treated patients with MMD during a long-term follow-up. STUDY TYPE: Prospective study. SUBJECTS: One hundred sixty conservatively managed patients with MMD (median age 46 years, 89 male). FIELD STRENGTH/SEQUENCE: Time of flight, turbo inversion recovery magnitude T1WI, turbo spin echo (TSE) T2WI, echo-planar imaging DWI, T2-fluid attenuated inversion recovery, dynamic susceptibility contrast-magnetic resonance imaging, and pre- and post-contrast 3D TSE T1WI sequences at 3.0 Tesla. ASSESSMENT: Patients were assessed at baseline and followed yearly. Ischemic and hemorrhagic stroke incidence rates were determined. Multiple demographic, clinical (modified Rankin score [mRS]), and cerebral imaging (cerebral blood volume [CBV] and concentric enhancement of arterial wall) factors at baseline were considered as potential predictors of stroke during the follow-up period. STATISTICAL TESTS: Univariable and multivariable Cox proportional hazards models to calculate the hazard ratios (HRs) and corresponding 95% confidence interval (CI) for stroke. Cumulative risk of stroke was estimated by the Kaplan-Meier product-limit method. A P value <0.05 was considered statistically significant. RESULTS: The median follow-up duration was 47 months. During the follow-up period, 18 (11.25%) patients experienced stroke events (13 [8.13%] ischemic, 5 [3.12%] hemorrhagic). Univariable analysis showed that 11 factors were significantly associated with stroke. After adjustment for clinical characteristics, multivariable analysis showed that mRS score ≥3 (HR, 1.99; 95% CI, 1.26-3.14), decreased CBV (HR, 5.31; 95% CI, 2.32-12.13), and concentric enhancement of the arterial wall (HR, 4.16; 95% CI, 1.55-11.15) were significantly associated with stroke. DATA CONCLUSION: Decreased CBV, mRS score ≥ 3, and concentric enhancement of the arterial wall were significantly associated with increased incidence of stroke in conservatively treated MMD. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 4.
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Doença de Moyamoya , Acidente Vascular Cerebral , Humanos , Masculino , Pessoa de Meia-Idade , Seguimentos , Doença de Moyamoya/complicações , Doença de Moyamoya/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Imageamento por Ressonância Magnética/métodosRESUMO
A series of solid-state emissive meso-aryl/alkyl-substituted and heteroatom-mixed bisBF2-anchoring fluorophore incorporating pyrrolyl-pyridylhydrazone (BOPPY) dyes have been developed by a one-pot condensation of ketonized or formylated pyrroles and 2-heterocyclohydrazine as well as the subsequent borylation coordination. Interestingly, the BOPPY dyes with meso-alkyl-substituted groups or oxygen-substituted pyridine moieties exhibit high fluorescence quantum yields (QYs) of up to 79%, the highest solid QY of 74%, and long lifetimes independent of polarity in the available BOPPYs. On the other hand, the BOPPYs with meso-aryl or N-substituted moieties display a high solution QY of up to 93% and slight emission wavelength maxima. However, the S-substituted BOPPY dye exhibited weak fluorescence in all studied solvents, which was attributed to the structural flexibility of the N-C-S bond and different from those BOPPYs with O or N substitution, indicated by quantum calculations. And the significant excited-state structural rearrangement in a polar solvent is further confirmed by femtosecond time-resolved transient absorption spectroscopy. More importantly, those novel and barely fluorescent BOPPYs in acetonitrile show advantageous aggregation-induced enhanced emission and viscosity-dependent activities. These advancements in the photophysical and electrochemical properties of BOPPY dyes offer valuable insights into their further development and potential applications.
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Rationale: Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease for which novel therapies are needed. External controls (ECs) could enhance IPF trial efficiency, but the direct comparability of ECs versus concurrent controls is unknown. Objectives: To develop IPF ECs by fit-for-purpose data standards to historical randomized clinical trial (RCT), multicenter registry (Pulmonary Fibrosis Foundation Patient Registry), and electronic health record (EHR) data and to evaluate endpoint comparability among ECs and the phase II RCT of BMS-986020. Methods: After data curation, the rate of change in FVC from baseline to 26 weeks among participants receiving BMS-986020 600 mg twice daily was compared with the BMS-placebo arm and ECs using mixed-effects models with inverse probability weights. Measurements and Main Results: At 26 weeks, the rates of change in FVC were -32.71 ml for BMS-986020 and -130.09 ml for BMS-placebo (difference, 97.4 ml; 95% confidence interval [CI], 24.6-170.2), replicating the original BMS-986020 RCT. RCT ECs showed treatment effect point estimates within the 95% CI of the original BMS-986020 RCT. Pulmonary Fibrosis Foundation Patient Registry ECs and EHR ECs experienced a slower rate of FVC decline compared with the BMS-placebo arm, resulting in treatment-effect point estimates outside of the 95% CI of the original BMS-986020 RCT. Conclusions: IPF ECs generated from historical RCT placebo arms result in comparable primary treatment effects to that of the original clinical trial, whereas ECs from real-world data sources, including registry or EHR data, do not. RCT ECs may serve as a potentially useful supplement to future IPF RCTs.
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Fibrose Pulmonar Idiopática , Fonte de Informação , Humanos , Capacidade Vital , Fibrose Pulmonar Idiopática/tratamento farmacológico , Pulmão , Resultado do Tratamento , Progressão da DoençaRESUMO
The aim of this study was to examine the expression changes of H2S, IGF-1, and GH in traumatic brain injury (TBI) patients and to detect their neuroprotective functions after TBI. In this study, we first collected cerebrospinal fluid (CSF) and plasma from TBI patients at different times after injury and evaluated the concentrations of H2S, IGF-1, and GH. In vitro studies were using the scratch-induced injury model and cell-cell interaction model (HT22 hippocampal neurons co-cultured with LPS-induced BV2 microglia cells). In vivo studies were using the controlled cortical impact (CCI) model in mice. Cell viability was assessed by CCK-8 assay. Pro-inflammatory cytokines expression was determined by qRT-PCR, ELISA, and nitric oxide production. Western blot was performed to assess the expression of CBS, CSE, IGF-1, and GHRH. Moreover, the recovery of TBI mice was evaluated for behavioral function by applying the modified Neurological Severity Score (mNSS), the Rotarod test, and the Morris water maze. We discovered that serum H2S, CSF H2S, and serum IGF-1 concentrations were all adversely associated with the severity of the TBI, while the concentrations of IGF-1 and GH in CSF and GH in the serum were all positively related to TBI severity. Experiments in vitro and in vivo indicated that treatment with NaHS (H2S donor), IGF-1, and MR-409 (GHRH agonist) showed protective effects after TBI. This study gives novel information on the functions of H2S, IGF-1, and GH in TBI.
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Cell senescence, glycolysis, and mitochondrial deficit jointly regulate the development of septic acute kidney injury (SAKI). This study aimed to explore the role of circular RNA HIPK3 (circHIPK3) in mitochondrial function in SAKI. The SAKI mouse model was established by Candida albicans infection, followed by Western blot assay, measurements of serum lactate, and adenosine triphosphate (ATP), 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimi-dazolylcarbocyanine iodide (JC-1) staining and flow cytometry. Human renal tubular epithelial cells were treated with lipopolysaccharide to establish the SAKI cell model, followed by cell counting kit-8 assay, tests of hexokinase activity, lactate production, oxygen consumption rate, extracellular acidification rate, ATP, and JC-1 staining, and Western blot assay. The roles of mitochondrial pyruvate carrier 1 (MPC1) were validated by kidney function tests, hematoxylin and eosin staining, periodic acid-Schiff staining, and SA-ß-gal staining. circHIPK3 downregulation reduced glycolysis and mitochondrial dysfunction both in vivo and in vitro through the microRNA (miR)-148b-3p/DNMT1/3a/Klotho axis. Inhibition of miR-148b-3p or Klotho increased glycolysis and mitochondrial dysfunction. Knockdown of MPC1 increased lactate content and decreased ATP levels and MMP both in vivo and in vitro. Collectively, circHIPK3, in concert with the miR-148b-3p/DNMT1/3a/Klotho axis, increased glycolysis, and inhibited the negative regulation of lactate production by MPC1, and aggravated mitochondrial dysfunction and cell senescence in SAKI.
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Injúria Renal Aguda , Benzimidazóis , Carbocianinas , MicroRNAs , Doenças Mitocondriais , Camundongos , Animais , Humanos , RNA Circular/genética , MicroRNAs/genética , Mitocôndrias , Injúria Renal Aguda/genética , Trifosfato de Adenosina , LactatosRESUMO
PURPOSE: To compare the clinical efficacy and complication rates between the medial midline and anterolateral portals in ankle arthroscopy for treating medial osteochondral lesions of the talus (OLTs). METHODS: We retrospectively analyzed patients with medial OLTs who underwent either a dual medial approach (via the medial midline and anteromedial portal) or a traditional approach (via the anterolateral and anteromedial portal) between June 2017 and January 2023. The degree of injury was evaluated by radiographs, computed tomography, and magnetic resonance imaging. Clinical outcomes were assessed using the visual analog scale (VAS), the American Orthopaedic Foot and Ankle Society (AOFAS) score, and the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scoring system. The incidence of postoperative complications, including superficial peroneal nerve (SPN) injury, was evaluated in all patients. RESULTS: There were 39 patients in total; 16 patients underwent the dual medial approach, and 23 patients underwent the traditional approach. The mean age was 39.4 ± 9.0 years, and the mean follow-up duration was 18.7 ± 6.4 months. The clinical outcomes improved significantly in both groups (*P < 0.05), but there was no significant difference between the two groups (P > 0.05). Postoperative complications were mainly SPN injury. The incidence of SPN injury was 13.0% in the traditional approach group and 0% in the dual medial approach group, with no significant difference between the two groups (P > 0.05), but a trend of reduction in SPN injury was observed in the dual medial approach group. CONCLUSION: The dual medial approach can also treat medial OLTs well, providing clear visualization and more convenient operation and reducing the possibility of injury to the SPN compared with the traditional approach. Therefore, we consider that the MM portal would be a good alternative to the anterolateral portal in treating medial OLTs.
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Articulação do Tornozelo , Artroscopia , Tálus , Humanos , Artroscopia/métodos , Artroscopia/efeitos adversos , Adulto , Masculino , Feminino , Tálus/cirurgia , Tálus/lesões , Estudos Retrospectivos , Pessoa de Meia-Idade , Articulação do Tornozelo/cirurgia , Articulação do Tornozelo/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Imageamento por Ressonância Magnética/métodos , Cartilagem Articular/cirurgia , Cartilagem Articular/lesões , Cartilagem Articular/patologiaRESUMO
OBJECTIVE: The study investigates the impact of preoperative rehabilitation on the surgical prognosis of frail older patients. METHOD: The effect sizes of all studies retrieved and included by the nine databases were analyzed and expressed as RR and WMD. RESULTS: 8 studies with 902 participants met the criteria for inclusion. A significant reduction in total complications (RR = 0.84, 95 % CI = 0.73 to 0.97, P = 0.021) and the 6MWT after surgery (WMD = 74.76, 95 % CI = 44.75 to 104.77, P = 0.000) was observed in the prehabilitation group. But it had no differences in mortality(RR = 1.89, 95 % CI = 0.75 to 4.72, P = 0.176), readmission rates(RR = 1.04, 95 % CI = 0.56 to 1.91, P = 0.906) and LOS(WMD = -0.24, 95 % CI = -1.00 to 0.52, P = 0.540). CONCLUSIONS: Prehabilitation had positive effect on postoperative complications and functional recovery in frail older patients.
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Idoso Fragilizado , Exercício Pré-Operatório , Humanos , Idoso , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Prognóstico , Recuperação de Função FisiológicaRESUMO
In this study, we highlight the impact of catalyst geometry on the formation of O-O bonds in Cu2 and Fe2 catalysts. A series of Cu2 complexes with diverse linkers are designed as electrocatalysts for water oxidation. Interestingly, the catalytic performance of these Cu2 complexes is enhanced as their molecular skeletons become more rigid, which contrasts with the behavior observed in our previous investigation with Fe2 analogs. Moreover, mechanistic studies reveal that the reactivity of the bridging O atom results in distinct pathways for O-O bond formation in Cu2 and Fe2 catalysts. In Cu2 systems, the coupling takes place between a terminal CuIII -OH and a bridging µ-Oâ radical. Whereas in Fe2 systems, it involves the coupling of two terminal Fe-oxo entities. Furthermore, an in-depth structure-activity analysis uncovers the spatial geometric prerequisites for the coupling of the terminal OH with the bridging µ-Oâ radical, ultimately leading to the O-O bond formation. Overall, this study emphasizes the critical role of precisely adjusting the spatial geometry of catalysts to align with the O-O bonding pathway.
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Solid-state lithium metal batteries (LMBs), constructed through the in situ fabrication of polymer electrolytes, are considered a critical strategy for the next-generation battery systems with high energy density and enhanced safety. However, the constrained oxidation stability of polymers, such as the extensively utilized polyethers, limits their applications in high-voltage batteries and further energy density improvements. Herein, an in situ fabricated fluorinated and crosslinked polyether-based gel polymer electrolyte, FGPE, is presented, exhibiting a high oxidation potential (5.1â V). The fluorinated polyether significantly improves compatibility with both lithium metal and high-voltage cathode, attributed to the electron-withdrawing -CF3 group and the generated LiF-rich electrolyte/electrode interphase. Consequently, the solid-state Li||LiNi0.6Co0.2Mn0.2O2 batteries employing FGPE demonstrate exceptional cycling performances of 1000 cycles with 78 % retention, representing one of the best results ever reported for polymer electrolytes. Moreover, FGPE enables batteries to operate at 4.7â V, realizing the highest operating voltage of polyether-based batteries to date. Notably, our designed in situ FGPE provides the solid-state batteries with exceptional cycling stability even at practical conditions, including high cathode loading (21â mg cm-2) and industry-level 18650-type cylindrical cells (1.3â Ah, 500 cycles). This work provides critical insights into the development of oxidation-stable polymer electrolytes and the advancement of practical high-voltage LMBs.
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The practical application of lithium metal batteries (LMBs) has been hindered by limited cycle-life and safety concerns. To solve these problems, we develop a novel fluorinated phosphate cross-linker for gel polymer electrolyte in high-voltage LMBs, achieving superior electrochemical performance and high safety simultaneously. The fluorinated phosphate cross-linked gel polymer electrolyte (FP-GPE) by in-situ polymerization method not only demonstrates high oxidation stability but also exhibits excellent compatibility with lithium metal anode. LMBs utilizing FP-GPE realize stable cycling even at a high cut-off voltage of 4.6â V (vs Li/Li+) with various high-voltage cathode materials. The LiNi0.6Co0.2Mn0.2O2|FP-GPE|Li battery exhibits an ultralong cycle-life of 1200 cycles with an impressive capacity retention of 80.1 %. Furthermore, the FP-GPE-based batteries display excellent electrochemical performance even at practical conditions, such as high cathode mass loading (20.84â mg cm-2), ultrathin Li (20â µm), and a wide temperature range of -25 to 80 °C. Moreover, the first reported solid-state 18650 cylindrical LMBs have been successfully fabricated and demonstrate exceptional safety under mechanical abuse. Additionally, the industry-level 18650 cylindrical LiMn2O4|FP-GPE|Li4Ti5O12 cells demonstrate a remarkable cycle-life of 1400 cycles. Therefore, the impressive electrochemical performance and high safety in practical batteries demonstrate a substantial potential of well-designed FP-GPE for large-scale industrial applications.
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RNA-binding proteins (RBPs) can regulate gene expression through post-transcriptionally influencing all manner of RNA biology, including alternative splicing (AS), polyadenylation, stability, and translation of mRNAs, as well as microRNAs (miRNAs) and circular RNAs (circRNAs) processing. There is accumulating evidence reinforcing the perception that dysregulation or dysfunction of RBPs can lead to various human diseases, including cancers. RBPs influence diverse cancer-associated cellular phenotypes, such as proliferation, apoptosis, senescence, migration, invasion, and angiogenesis, contributing to the initiation and development of tumors, as well as clinical prognosis. Metastasis is the leading cause of cancer-related recurrence and death. Therefore, it is necessary to elucidate the molecular mechanisms behind tumor metastasis. In fact, a growing body of published research has proved that RBPs play pivotal roles in cancer metastasis. In this review, we will summarize the recent advances for helping us understand the role of RBPs in tumor metastasis, and discuss dysfunctions and dysregulations of RBPs affecting metastasis-associated processes including epithelial-mesenchymal transition (EMT), migration, and invasion of cancer cells. Furthermore, we will discuss emerging RBP-based strategy for the treatment of cancer metastasis.
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MicroRNAs , Neoplasias , Humanos , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , RNA Circular/genética , Transição Epitelial-Mesenquimal/genética , MicroRNAs/genética , Neoplasias/genética , Neoplasias/metabolismoRESUMO
BACKGROUND: Clustering analysis is widely used to interpret biomedical data and uncover new knowledge and patterns. However, conventional clustering methods are not effective when dealing with sparse biomedical data. To overcome this limitation, we propose a hierarchical clustering method called polynomial weight-adjusted sparse clustering (PWSC). RESULTS: The PWSC algorithm adjusts feature weights using a polynomial function, redefines the distances between samples, and performs hierarchical clustering analysis based on these adjusted distances. Additionally, we incorporate a consensus clustering approach to determine the optimal number of classifications. This consensus approach utilizes relative change in the cumulative distribution function to identify the best number of clusters, resulting in more stable clustering results. Leveraging the PWSC algorithm, we successfully classified a cohort of gastric cancer patients, enabling categorization of patients carrying different types of altered genes. Further evaluation using Entropy showed a significant improvement (p = 2.905e-05), while using the Calinski-Harabasz index demonstrates a remarkable 100% improvement in the quality of the best classification compared to conventional algorithms. Similarly, significantly increased entropy (p = 0.0336) and comparable CHI, were observed when classifying another colorectal cancer cohort with microbial abundance. The above attempts in cancer subtyping demonstrate that PWSC is highly applicable to different types of biomedical data. To facilitate its application, we have developed a user-friendly tool that implements the PWSC algorithm, which canbe accessed at http://pwsc.aiyimed.com/ . CONCLUSIONS: PWSC addresses the limitations of conventional approaches when clustering sparse biomedical data. By adjusting feature weights and employing consensus clustering, we achieve improved clustering results compared to conventional methods. The PWSC algorithm provides a valuable tool for researchers in the field, enabling more accurate and stable clustering analysis. Its application can enhance our understanding of complex biological systems and contribute to advancements in various biomedical disciplines.