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Argonaute (Ago) proteins mediate RNA- or DNA-guided inhibition of nucleic acids1,2. Although the mechanisms used by eukaryotic Ago proteins and long prokaryotic Ago proteins (pAgos) are known, that used by short pAgos remains elusive. Here we determined the cryo-electron microscopy structures of a short pAgo and the associated TIR-APAZ proteins (SPARTA) from Crenotalea thermophila (Crt): a free-state Crt-SPARTA; a guide RNA-target DNA-loaded Crt-SPARTA; two Crt-SPARTA dimers with distinct TIR organization; and a Crt-SPARTA tetramer. These structures reveal that Crt-SPARTA is composed of a bilobal-fold Ago lobe that connects with a TIR lobe. Whereas the Crt-Ago contains a MID and a PIWI domain, Crt-TIR-APAZ has a TIR domain, an N-like domain, a linker domain and a trigger domain. The bound RNA-DNA duplex adopts a B-form conformation that is recognized by base-specific contacts. Nucleic acid binding causes conformational changes because the trigger domain acts as a 'roadblock' that prevents the guide RNA 5' ends and the target DNA 3' ends from reaching their canonical pockets; this disorders the MID domain and promotes Crt-SPARTA dimerization. Two RNA-DNA-loaded Crt-SPARTA dimers form a tetramer through their TIR domains. Four Crt-TIR domains assemble into two parallel head-to-tail-organized TIR dimers, indicating an NADase-active conformation, which is supported by our mutagenesis study. Our results reveal the structural basis of short-pAgo-mediated defence against invading nucleic acids, and provide insights for optimizing the detection of SPARTA-based programmable DNA sequences.
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Proteínas Argonautas , Microscopia Crioeletrônica , NAD+ Nucleosidase , Ácidos Nucleicos , Proteínas Argonautas/química , Proteínas Argonautas/metabolismo , Proteínas Argonautas/ultraestrutura , DNA/química , DNA/genética , DNA/metabolismo , DNA/ultraestrutura , Ativação Enzimática , NAD+ Nucleosidase/química , NAD+ Nucleosidase/genética , NAD+ Nucleosidase/metabolismo , NAD+ Nucleosidase/ultraestrutura , Conformação de Ácido Nucleico , Ácidos Nucleicos/metabolismo , Conformação Proteica , RNA Guia de Sistemas CRISPR-Cas , MutagêneseRESUMO
BACKGROUND: Population screening of asymptomatic persons with Epstein-Barr virus (EBV) DNA or antibodies has improved the diagnosis of nasopharyngeal carcinoma and survival among affected persons. However, the positive predictive value of current screening strategies is unsatisfactory even in areas where nasopharyngeal carcinoma is endemic. METHODS: We designed a peptide library representing highly ranked B-cell epitopes of EBV coding sequences to identify novel serologic biomarkers for nasopharyngeal carcinoma. After a retrospective case-control study, the performance of the novel biomarker anti-BNLF2b total antibody (P85-Ab) was validated through a large-scale prospective screening program and compared with that of the standard two-antibody-based screening method (EBV nuclear antigen 1 [EBNA1]-IgA and EBV-specific viral capsid antigen [VCA]-IgA). RESULTS: P85-Ab was the most promising biomarker for nasopharyngeal carcinoma screening, with high sensitivity (94.4%; 95% confidence interval [CI], 86.4 to 97.8) and specificity (99.6%; 95% CI, 97.8 to 99.9) in the retrospective case-control study. Among the 24,852 eligible participants in the prospective cohort, 47 cases of nasopharyngeal carcinoma (38 at an early stage) were identified. P85-Ab showed higher sensitivity than the two-antibody method (97.9% vs. 72.3%; ratio, 1.4 [95% CI, 1.1 to 1.6]), higher specificity (98.3% vs. 97.0%; ratio, 1.01 [95% CI, 1.01 to 1.02]), and a higher positive predictive value (10.0% vs. 4.3%; ratio, 2.3 [95% CI, 1.8 to 2.8]). The combination of P85-Ab and the two-antibody method markedly increased the positive predictive value to 44.6% (95% CI, 33.8 to 55.9), with sensitivity of 70.2% (95% CI, 56.0 to 81.4). CONCLUSIONS: Our results suggest that P85-Ab is a promising novel biomarker for nasopharyngeal carcinoma screening, with higher sensitivity, specificity, and positive predictive value than the standard two-antibody method. (Funded by the National Key Research and Development Program of China and others; ClinicalTrials.gov number, NCT04085900.).
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Anticorpos Antivirais , Detecção Precoce de Câncer , Herpesvirus Humano 4 , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Proteínas Virais , Humanos , Anticorpos Antivirais/imunologia , Estudos de Casos e Controles , Herpesvirus Humano 4/imunologia , Imunoglobulina A , Programas de Rastreamento , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/virologia , Estudos Prospectivos , Estudos Retrospectivos , Biomarcadores/análise , Proteínas Virais/imunologia , Epitopos/imunologiaRESUMO
BACKGROUND: Intracellular Ca2+ cycling determines myocardial contraction and relaxation in response to physiological demands. SERCA2a (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2a) is responsible for the sequestration of cytosolic Ca2+ into intracellular stores during cardiac relaxation, and its activity is reversibly inhibited by PLN (phospholamban). However, the regulatory hierarchy of SERCA2a activity remains unclear. METHODS: Cardiomyocyte-specific ZBTB20 knockout mice were generated by crossing ZBTB20flox mice with Myh6-Cre mice. Echocardiography, blood pressure measurements, Langendorff perfusion, histological analysis and immunohistochemistry, quantitative reverse transcription-PCR, Western blot analysis, electrophysiological measurements, and chromatin immunoprecipitation assay were performed to clarify the phenotype and elucidate the molecular mechanisms. RESULTS: Specific ablation of ZBTB20 in cardiomyocyte led to a significant increase in basal myocardial contractile parameters both in vivo and in vitro, accompanied by an impairment in cardiac reserve and exercise capacity. Moreover, the cardiomyocytes lacking ZBTB20 showed an increase in sarcoplasmic reticular Ca2+ content and exhibited a remarkable enhancement in both SERCA2a activity and electrically stimulated contraction. Mechanistically, PLN expression was dramatically reduced in cardiomyocytes at the mRNA and protein levels by ZBTB20 deletion or silencing, and PLN overexpression could largely restore the basal contractility in ZBTB20-deficient cardiomyocytes. CONCLUSIONS: These data point to ZBTB20 as a fine-tuning modulator of PLN expression and SERCA2a activity, thereby offering new perspective on the regulation of basal contractility in the mammalian heart.
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Miocárdio , Retículo Sarcoplasmático , Animais , Camundongos , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Mamíferos , Camundongos Knockout , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismoRESUMO
Chemotherapy-induced peripheral neuropathy (CIPN) is a persistent and irreversible side effect of antineoplastic agents. Patients with CIPN usually show chronic pain and sensory deficits with glove-and-stocking distribution. However, whether spinal neuronal microRNA (miR)-124 is involved in cisplatin-induced peripheral neuropathy remains to be studied. In this study, miR-124 was significantly reduced in the spinal dorsal horn in CIPN mice. Overexpression of neuronal miR-124 induced by injecting adeno-associated virus with neuron-specific promoter into the spinal cord of mice prevented the development of mechanical allodynia, sensory deficits, and the loss of intraepidermal nerve fibers induced by cisplatin. Meanwhile, cisplatin-induced M1 microglia activation and the release of proinflammatory cytokines were significantly inhibited by overexpression of neuronal miR-124. Furthermore, electroacupuncture (EA) treatment upregulated miR-124 expression in the spinal dorsal horn of CIPN mice. Interestingly, downregulation of spinal neuronal miR-124 significantly inhibited the regulatory effect of EA on CIPN and microglia activity as well as spinal neuroinflammation induced by cisplatin. These results demonstrate that spinal neuronal miR-124 is involved in the prevention and treatment of EA on cisplatin-induced peripheral neuropathy in mice. Our findings suggest that spinal neuronal miR-124 might be a potential target for EA effect, and we provide, to our knowledge, a new experimental basis for EA prevention of CIPN.
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Antineoplásicos , Eletroacupuntura , MicroRNAs , Doenças do Sistema Nervoso Periférico , Humanos , Camundongos , Animais , Cisplatino/toxicidade , Microglia , Paclitaxel/efeitos adversos , Antineoplásicos/toxicidade , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/prevenção & controle , Neurônios/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismoRESUMO
The mammalian cochlear epithelium undergoes substantial remodeling and maturation before the onset of hearing. However, very little is known about the transcriptional network governing cochlear late-stage maturation and particularly the differentiation of its lateral nonsensory region. Here, we establish ZBTB20 as an essential transcription factor required for cochlear terminal differentiation and maturation and hearing. ZBTB20 is abundantly expressed in the developing and mature cochlear nonsensory epithelial cells, with transient expression in immature hair cells and spiral ganglion neurons. Otocyst-specific deletion of Zbtb20 causes profound deafness with reduced endolymph potential in mice. The subtypes of cochlear epithelial cells are normally generated, but their postnatal development is arrested in the absence of ZBTB20, as manifested by an immature appearance of the organ of Corti, malformation of tectorial membrane (TM), a flattened spiral prominence (SP), and a lack of identifiable Boettcher cells. Furthermore, these defects are related with a failure in the terminal differentiation of the nonsensory epithelium covering the outer border Claudius cells, outer sulcus root cells, and SP epithelial cells. Transcriptome analysis shows that ZBTB20 regulates genes encoding for TM proteins in the greater epithelial ridge, and those preferentially expressed in root cells and SP epithelium. Our results point to ZBTB20 as an essential regulator for postnatal cochlear maturation and particularly for the terminal differentiation of cochlear lateral nonsensory domain.
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Cóclea , Células Ciliadas Auditivas , Animais , Camundongos , Cóclea/metabolismo , Células Ciliadas Auditivas/fisiologia , Audição/fisiologia , Mamíferos , Gânglio Espiral da Cóclea , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Responsive spin-crossover (SCO) metal-organic cages (MOCs) are emerging dynamic platforms with potential for advanced applications in magnetic sensing and molecular switching. Among these, FeIII-based MOCs are particularly noteworthy for their air stability, yet they remain largely unexplored. Herein, we report the synthesis of two novel FeIII MOCs using a bis-bidentate ligand approach, which exhibit SCO activity above room temperature. These represent the first SCO-active FeIII cages and feature an atypical {FeN6}-type coordination sphere, uncommon for FeIII SCO compounds. Our study reveals that these MOCs are sensitive to acid/base variations, enabling reversible magnetic switching in solution. The presence of multiple active proton sites within these SCO-MOCs facilitates multisite, multilevel proton-induced spin-state modulation. This behavior is observed at room temperature through 1H NMR spectroscopy, capturing the subtle proton-induced spin-state transitions triggered by pH changes. Further insights from extended X-ray absorption fine structure (EXAFS) and theoretical analyses indicate that these magnetic alterations primarily result from the protonation and deprotonation processes at the NH active sites on the ligands. These processes induce changes in the secondary coordination sphere, thereby modulating the magnetic properties of the cages. The capability of these FeIII MOCs to integrate magnetic responses with environmental stimuli underscores their potential as finely tunable magnetic sensors and highlights their versatility as molecular switches. This work paves the way for the development of SCO-active materials with tailored properties for applications in sensing and molecular switching.
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The application of Si anodes is hindered by some critical issues such as large volume changes of bare Si and fragile solid-electrolyte interface (SEI), resulting in low coulombic efficiency and rapid capacity decay. Herein, a multifunctional SEI film with high content of LiF is in situ constructed via the surface grafting of carbon-fluorine functionalized groups on silicon nanoparticles (SiNPs) during cycling. Mechanical study demonstrates that the incorporation of LiF with high modulus and unbroken carbon-fluorine groups with highly elastic guarantee the rigid-soft coupling SEI film on Si electrode. Furthermore, it is demonstrated that the rigid-soft coupling SEI film can effectively accommodate the volume expansion of Si nanoparticles during lithiation process, with the electrode expanding rate of only 114.16% after 100 cycles (263.87% for bare Si without surface modification). Afterward, with the aid of well-designed rigid-soft coupling SEI, the initial Coulomb efficiency of 89.8% is achieved, showing a reversible capacity of 1477 mAh g-1 after 200 cycles at 1.2 A g-1 . This work provides a simple and efficient solution that can potentially facilitate the practical application of Si anodes.
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Protecting haploid pollen and spores against UV-B light and high temperature, 2 major stresses inherent to the terrestrial environment, is critical for plant reproduction and dispersal. Here, we show flavonoids play an indispensable role in this process. First, we identified the flavanone naringenin, which serves to defend against UV-B damage, in the sporopollenin wall of all vascular plants tested. Second, we found that flavonols are present in the spore/pollen protoplasm of all euphyllophyte plants tested and that these flavonols scavenge reactive oxygen species to protect against environmental stresses, particularly heat. Genetic and biochemical analyses showed that these flavonoids are sequentially synthesized in both the tapetum and microspores during pollen ontogeny in Arabidopsis (Arabidopsis thaliana). We show that stepwise increases in the complexity of flavonoids in spores/pollen during plant evolution mirror their progressive adaptation to terrestrial environments. The close relationship between flavonoid complexity and phylogeny and its strong association with pollen survival phenotypes suggest that flavonoids played a central role in the progression of plants from aquatic environments into progressively dry land habitats.
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Arabidopsis , Flavonoides , Plantas , Pólen/genética , Arabidopsis/genética , Flavonóis , EsporosRESUMO
Characterization of single-frequency lasers (SFLs) requires a precise measurement of their phase noise. However, there exists a contradiction between the frequency range and laser phase noise measurement sensitivity in the delay self-heterodyne method. Achieving a broadband and highly sensitive phase noise measurement often requires overlapping the results obtained from different delay lengths. In this study, we present a precisely designed short-fiber recirculating delayed self-heterodyne (SF-RDSH) method that enables the broadband and highly sensitive laser phase noise measurement in a compact setup. By designing the length of the delay fiber based on a theoretical model, the RDSH technique with a shortest delay length of 200â m enables a highly sensitive laser phase noise measurement from 1â Hz to 1â MHz for the first time, to our knowledge. In the experiment, we demonstrate the broadband phase noise measurement of an SFL by analyzing the 1st and 10th beat notes.
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AIM: The wealth of data generated by continuous glucose monitoring (CGM) provides new opportunities for revealing heterogeneities in patients with type 2 diabetes mellitus (T2DM). We aimed to develop a method using CGM data to discover T2DM subtypes and investigate their relationship with clinical phenotypes and microvascular complications. METHODS: The data from 3119 patients with T2DM who wore blinded CGM at an academic medical centre was collected, and a glucose symbolic pattern (GSP) metric was created that combined knowledge-based temporal abstraction with numerical vectorization. The k-means clustering was applied to GSP to obtain subgroups of patients with T2DM. Clinical characteristics and the presence of diabetic retinopathy and albuminuria were compared among the subgroups. The findings were validated in an independent population comprising 773 patients with T2DM. RESULTS: By using GSP, four subgroups were identified with distinct features in CGM profiles and parameters. Moreover, the clustered subgroups differed significantly in clinical phenotypes, including indices of pancreatic ß-cell function and insulin resistance (all p < .001). After adjusting for confounders, group C (the most insulin resistant) had a significantly higher risk of albuminuria (odds ratio = 1.24, 95% confidence interval: 1.03-1.39) relative to group D, which had the best glucose control. These findings were confirmed in the validation set. CONCLUSION: Subtyping patients with T2DM using CGM data may help identify high-risk patients for microvascular complications and provide insights into the underlying pathophysiology. This method may help refine clinically meaningful stratification of patients with T2DM and inform personalized diabetes care.
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Albuminúria , Diabetes Mellitus Tipo 2 , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Albuminúria/sangue , Glicemia/análise , Monitoramento Contínuo da Glicose , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/diagnóstico , Retinopatia Diabética/sangue , Retinopatia Diabética/etiologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Resistência à InsulinaRESUMO
BACKGROUND: Lower plasma levels of LDL (low-density lipoprotein) cholesterol (LDL-C) can reduce the risk of atherosclerotic cardiovascular disease. The loss-of-function mutations in PCSK9 (proprotein convertase subtilisin/kexin type 9) have been known to associate with low LDL-C in many human populations. PCSK9 genetic variants in Chinese Uyghurs who are at high risk of atherosclerotic cardiovascular disease due to their dietary habits have not been reported. METHODS: The study involved the whole-exome and target sequencing of college students from Uyghur and other ethnic groups in Xinjiang, China, for the association of PCSK9 loss-of-function mutations with low plasma levels of LDL-C. The mechanisms by which the identified mutations affect the function of PCSK9 were investigated in cultured cells using biochemical and cell assays. The causal effects of the identified PCSK9 mutations on LDL-C levels were verified in mice injected with adeno-associated virus expressing different forms of PCSK9 and fed a high-cholesterol diet. RESULTS: We identified 2 PCSK9 mutations-E144K and C378W-in Chinese Uyghurs with low plasma levels of LDL-C. The E144K and C378W mutations impaired the maturation and secretion of the PCSK9 protein, respectively. Adeno-associated virus-mediated expression of E144K and C378W mutants in Pcsk9 KO (knockout) mice fed a high-cholesterol diet also hampered PCSK9 secretion into the serum, resulting in elevated levels of LDL receptor in the liver and reduced levels of LDL-C in the serum. CONCLUSIONS: Our study shows that E144K and C378W are PCSK9 loss-of-function mutations causing low LDL-C levels in mice and probably in humans as well.
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Aterosclerose , Doenças Cardiovasculares , Hipercolesterolemia , Humanos , Camundongos , Animais , Pró-Proteína Convertase 9/genética , LDL-Colesterol , Serina Endopeptidases/genética , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Camundongos Knockout , Aterosclerose/genética , Aterosclerose/prevenção & controle , Aterosclerose/metabolismo , MutaçãoRESUMO
BACKGROUND: This study aimed to develop a tool for predicting the early occurrence of acute kidney injury (AKI) in ICU hospitalized cirrhotic patients. METHODS: Eligible patients with cirrhosis were identified from the Medical Information Mart for Intensive Care database. Demographic data, laboratory examinations, and interventions were obtained. After splitting the population into training and validation cohorts, the least absolute shrinkage and selection operator regression model was used to select factors and construct the dynamic online nomogram. Calibration and discrimination were used to assess nomogram performance, and clinical utility was evaluated by decision curve analysis (DCA). RESULTS: A total of 1254 patients were included in the analysis, and 745 developed AKI. The mean arterial pressure, white blood cell count, total bilirubin level, Glasgow Coma Score, creatinine, heart rate, platelet count and albumin level were identified as predictors of AKI. The developed model had a good ability to differentiate AKI from non-AKI, with AUCs of 0.797 and 0.750 in the training and validation cohorts, respectively. Moreover, the nomogram model showed good calibration. DCA showed that the nomogram had a superior overall net benefit within wide and practical ranges of threshold probabilities. CONCLUSIONS: The dynamic online nomogram can be an easy-to-use tool for predicting the early occurrence of AKI in critically ill patients with cirrhosis.
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Injúria Renal Aguda , Unidades de Terapia Intensiva , Cirrose Hepática , Nomogramas , Humanos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/sangue , Injúria Renal Aguda/etiologia , Masculino , Feminino , Cirrose Hepática/complicações , Pessoa de Meia-Idade , Idoso , Estado Terminal , Bases de Dados Factuais , Creatinina/sangue , Fatores de Risco , Hospitalização , Estudos RetrospectivosRESUMO
BACKGROUND: Liver diseases were significant source of early readmission burden. This study aimed to evaluate the 30-day unplanned readmission rates, causes of readmissions, readmission costs, and predictors of readmission in patients with acute liver failure (ALF). METHODS: Patients admitted for ALF from 2019 National Readmission Database were enrolled. Weighted multivariable logistic regression models were applied and based on Directed Acyclic Graphs. Incidence, causes, cost, and predictors of 30-day unplanned readmissions were identified. RESULTS: A total of 3,281 patients with ALF were enrolled, of whom 600 (18.3%) were readmitted within 30 days. The mean time from discharge to early readmission was 12.6 days. The average hospital cost and charge of readmission were $19,629 and $86,228, respectively. The readmissions were mainly due to liver-related events (26.6%), followed by infection (20.9%). The predictive factors independently associated with readmissions were age, male sex (OR 1.227, 95% CI 1.023-1.472; P = 0.028), renal failure (OR 1.401, 95% CI 1.139-1.723; P = 0.001), diabetes with chronic complications (OR 1.327, 95% CI 1.053-1.672; P = 0.017), complicated hypertension (OR 1.436, 95% CI 1.111-1.857; P = 0.006), peritoneal drainage (OR 1.600, 95% CI 1.092-2.345; P = 0.016), etc. CONCLUSIONS: Patients with ALF are at relatively high risk of early readmission, which imposes a heavy medical and economic burden on society. We need to increase the emphasis placed on early readmission of patients with ALF and establish clinical strategies for their management.
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Bases de Dados Factuais , Falência Hepática Aguda , Readmissão do Paciente , Humanos , Readmissão do Paciente/estatística & dados numéricos , Masculino , Feminino , Pessoa de Meia-Idade , Falência Hepática Aguda/economia , Falência Hepática Aguda/terapia , Fatores de Risco , Adulto , Idoso , Custos Hospitalares/estatística & dados numéricos , Fatores Sexuais , Fatores de Tempo , Modelos Logísticos , Fatores Etários , IncidênciaRESUMO
Lithium-sulfur batteries (LSBs) are one of the most promising energy storage devices with high energy density. However, their application and commercialization are hampered by the slow Li-S redox chemistry. Fe0.875M0.125S2 (M = Ti, V), as the sulfur cathode host, enhances the Li-S redox chemistry. FeS2 with Pa3Ì is transformed into Li2FeS2 with P3Ìm1 after discharge. The structure changes and physicochemical properties during Fe0.875M0.125S2 discharge process are further investigated to screen out the sulfur cathode host materials with the best comprehensive properties. The discharge structure of Fe0.875M0.125S2 is verified by the thermodynamic stability of Li-deficient phases, voltage and capacity based on Monte Carlo methods. Fe0.875M0.125S2 with Pa3Ì is transformed into Li2Fe0.875M0.125S2 with P3Ìm1 after discharge. Using the first-principles calculations, the physicochemical properties of Li2Fe0.875M0.125S2 are systematically investigated, including the formation energy, voltage, theoretical capacity, electrical conductivity, Li+ diffusion, catalytic performance and Li2S oxidation decomposition. The average redox voltage of Li2Fe0.875V0.125S2 is higher than that of Li2Fe0.875Ti0.125S2. Li2Fe0.875M0.125S2 shows metallic properties. Li2Fe0.875V0.125S2 is more beneficial to the reduction reaction of Li2S2 and Li2S oxidation decomposition. Fe0.875V0.125S2 has more potential as the sulfur cathode host than Fe0.875Ti0.125S2 in LSBs. A new strategy for the selection of the sulfur cathode host material for LSBs is provided by this work.
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Nuclear magnetic resonance (NMR) chemical shift calculations are powerful tools for structure elucidation and have been extensively employed in both natural product and synthetic chemistry. However, density functional theory (DFT) NMR chemical shift calculations are usually time-consuming, while fast data-driven methods often lack reliability, making it challenging to apply them to computationally intensive tasks with a high requirement on quality. Herein, we have constructed a 54-layer-deep graph convolutional network for 13C NMR chemical shift calculations, which achieved high accuracy with low time-cost and performed competitively with DFT NMR chemical shift calculations on structure assignment benchmarks. Our model utilizes a semiempirical method, GFN2-xTB, and is compatible with a broad variety of organic systems, including those composed of hundreds of atoms or elements ranging from H to Rn. We used this model to resolve the controversial J/K ring junction problem of maitotoxin, which is the largest whole molecule assigned by NMR calculations to date. This model has been developed into user-friendly software, providing a useful tool for routine rapid structure validation and assignation as well as a new approach to elucidate the large structures that were previously unsuitable for NMR calculations.
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Teoria da Densidade Funcional , Estrutura Molecular , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Oxocinas/química , SoftwareRESUMO
In karst areas, the dissolved inorganic carbon (DIC) concentrations in aquatic systems are typically higher than that in non-karst areas due to intensive carbonate rock weathering. Understanding the sources and input fluxes of DIC in karst reservoirs is crucial for regional carbon cycle studies. This study utilized dual carbon isotopes (δ13CDIC and Δ14CDIC) to estimate the contribution rates and input fluxes of DIC from various sources in Aha Reservoir (AHR), located in southwestern China. Our results indicated that the DIC concentrations (22.33-32.79 mg L-1) and δ13CDIC values (-10.02 to -8.55) were nearly homogeneous both vertically and laterally in the reservoir (p > 0.05). The Δ14CDIC values (-246.31 to -137.86) were homogeneous along the vertical profile (p > 0.05), but showed significant horizontal variation (p < 0.05), with values decreasing from -149.57 ± 10.27 to -232.85 ± 2.37 at the mouths of the inflowing rivers. We found that the inflowing rivers were the primary DIC sources to AHR, contributing 70% of the total input, while groundwater and atmospheric CO2 contributions were relatively minor, at 18% and 12%, respectively. The Jinzhong River (JZR), influenced by industrial and domestic wastewater discharge, contributed the largest DIC input flux at 2.01 t/(km2·mon). In contrast, the Youyu River (YYR), influenced by acidic mine drainage, and the Baiyan River (BYR), influenced by agricultural activities, contributed relatively smaller DIC input fluxes of 1.29 t/(km2·mon) and 1.03 t/(km2·mon), respectively. This study highlights the significant impact of anthropogenic activities on DIC input in AHR, with industrial and domestic wastewater discharges having a greater influence than agricultural activities and acidic mine wastewater inputs. These findings underscore the critical need to manage and mitigate the impacts of human activities on karst reservoir ecosystems.
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OBJECTIVE: This systematic review and meta-analysis investigated whether the use of azithromycin during labour or caesarean section reduces the incidence of sepsis and infection among mothers and newborns. DATA SOURCES: We independently searched the PubMed, Web of Science, Cochrane Library and EMBASE databases for relevant studies published before February, 2024. METHODS: We included RCTs that evaluated the effect of prenatal oral or intravenous azithromycin or placebo on intrapartum or postpartum infection incidence. We included studies evaluating women who had vaginal births as well as caesarean sections. Studies reporting maternal and neonatal infections were included in the current analysis. Review Manager 5.4 was used to analyse 6 randomized clinical trials involving 44,448 mothers and 44,820 newborns. The risk of bias of each included study was assessed using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions.Primary outcomes included the incidence of maternal sepsis and all-cause mortality and neonatal sepsis and all-cause mortality; secondary outcomes included maternal (endometritis, wound and surgical site infections, chorioamnionitis, and urinary tract infections) and neonatal outcomes (infections of the eyes, ears and skin). A random-effects model was used to test for overall effects and heterogeneity. RESULTS: The pooled odds ratios (ORs) were as follows: 0.65 for maternal sepsis (95% CI, 0.55-0.77; I2, 0%; P < .00001); 0.62 for endometritis (95% CI, 0.52-0.74; I2, 2%; P < .00001); and 0.43 for maternal wound or surgical site infection (95% CI, 0.24-0.78; P < .005); however, there was great heterogeneity among the studies (I2, 75%). The pooled OR for pyelonephritis and urinary tract infections was 0.3 (95% CI, 0.17-0.52; I2, 0%; P < .0001), and that for neonatal skin infections was 0.48 (95% CI, 0.35-0.65; I2, 0%, P < .00001). There was no significant difference in maternal all-cause mortality or incidence of chorioamnionitis between the two groups. No significant differences were observed in the incidence of neonatal sepsis or suspected sepsis, all-cause mortality, or infections of the eyes or ears. CONCLUSION: In this meta-analysis, azithromycin use during labour reduced the incidence of maternal sepsis, endometritis, incisional infections and urinary tract infections but did not reduce the incidence of neonatal-associated infections, except for neonatal skin infections. These findings indicate that azithromycin may be potentially beneficial for maternal postpartum infections, but its effect on neonatal prognosis remains unclear. Azithromycin should be used antenatally only if the clinical indication is clear and the potential benefits outweigh the harms.
Assuntos
Antibacterianos , Azitromicina , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Azitromicina/uso terapêutico , Azitromicina/administração & dosagem , Feminino , Gravidez , Recém-Nascido , Antibacterianos/uso terapêutico , Incidência , Trabalho de Parto , Cesárea/estatística & dados numéricos , Infecção Puerperal/prevenção & controle , Infecção Puerperal/epidemiologia , Endometrite/prevenção & controle , Endometrite/epidemiologia , Sepse/prevenção & controle , Sepse/epidemiologia , Sepse Neonatal/prevenção & controle , Sepse Neonatal/epidemiologiaRESUMO
BACKGROUND: Myopia is the most prevalent refractive error and a growing global health concern that significantly affects visual function. Researchers have recently emphasized considerably on the influence of lifestyle on myopia incidence and development. This study investigates the relationship between leisure sedentary behaviors (LSB)/physical activity (PA)/sleep traits and myopia. METHODS: LSB, PA, and sleep trait-associated genetic variants were used as instrument variables in a Mendelian randomization (MR) study to examine their causal effects on myopia. Summary genome-wide association studies (GWASs) statistical data for LSB and PA were obtained from UK Biobank, and the data of sleep traits was obtained from UK Biobank, UK Biobank and 23andMe, and FinnGen. We used summary statistics data for myopia from MRC IEU. The MR analyses was performed using the inverse variance-weighted (IVW), MR-Egger, weighted median, and MR Pleiotropy RESidual Sum and Outlier methods. RESULTS: Computer use was genetically predicted to increase the myopia risk [IVW odds ratio (OR) = 1.057; 95% confidence interval (CI), 1.038-1.078; P = 7.04 × 10- 9]. The self-reported moderate-to-vigorous physical activity (MVPA) (IVW OR = 0.962; 95% CI, 0.932-0.993; P = 1.57 × 10- 2) and television watching (IVW OR = 0.973; 95% CI, 0.961-0.985, P = 1.93 × 10- 5) were significantly associated with a lower myopia risk. However, genetically predicted sleep traits or accelerometer-measured physical activity had no significant associations with myopia. CONCLUSION: Our results indicated that computer use is a risk factor for myopia, whereas television watching and MVPA may protect against myopia. These findings shed new light on possible strategies for reducing the prevalence of myopia.
Assuntos
Miopia , Comportamento Sedentário , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Miopia/epidemiologia , Miopia/genética , Exercício Físico , Sono , Atividades de LazerRESUMO
Triple negative breast cancer (TNBC) has a high recurrence rate, metastasis rate and mortality rate. The aim of this study is to identify new targets for the treatment of TNBC. Clinical samples are used for screening deubiquitinating enzymes (DUBs). MDA-MB-231 cells and a TNBC mouse model are used for in vitro and in vivo experiments, respectively. Western blot analysis is used to detect the protein expressions of DUBs, zinc finger E-box binding homeobox 1 (ZEB1), and epithelial-mesenchymal transition (EMT)-related markers. Colony formation and transwell assays are used to detect the proliferation, migration and invasion of TNBC cells. Wound healing assay is used to detect the mobility of TNBC cells. Immunoprecipitation assay is used to detect the interaction between breast cancer susceptibility gene 1/2-containing complex subunit 3 (BRCC3) and ZEB1. ZEB1 ubiquitination levels, protein stability, and protein degradation are also examined. Pathological changes in the lung tissues are detected via HE staining. Our results show a significant positive correlation between the expressions of BRCC3 and ZEB1 in clinical TNBC tissues. Interference with BRCC3 inhibits TNBC cell proliferation, migration, invasion and EMT. BRCC3 interacts with ZEB1 and interferes with BRCC3 to inhibit ZEB1 expression by increasing ZEB1 ubiquitination. Interference with BRCC3 inhibits TNBC cell tumorigenesis and lung metastasis in vivo. In all, this study demonstrates that BRCC3 can increase the stability of ZEB1, upregulate ZEB1 expression, and promote the proliferation, migration, invasion, EMT, and metastasis of TNBC cells, providing a new direction for cancer therapy.
Assuntos
Neoplasias da Mama , Enzimas Desubiquitinantes , Neoplasias de Mama Triplo Negativas , Homeobox 1 de Ligação a E-box em Dedo de Zinco , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Enzimas Desubiquitinantes/genética , Enzimas Desubiquitinantes/metabolismo , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Mama Triplo Negativas/patologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismoRESUMO
During pregnancy, the appropriate allocation of nutrients between the mother and the fetus is dominated by maternal-fetal interactions, which is primarily governed by the placenta. The syncytiotrophoblast (STB) lining at the outer surface of the placental villi is directly bathed in maternal blood and controls feto-maternal exchange. The STB is the largest multinucleated cell type in the human body, and is formed through syncytialization of the mononucleated cytotrophoblast. However, the physiological advantage of forming such an extensively multinucleated cellular structure remains poorly understood. Here, we discover that the STB uniquely adapts to nutrient stress by inducing the macropinocytosis machinery through repression of mammalian target of rapamycin (mTOR) signaling. In primary human trophoblasts and in trophoblast cell lines, differentiation toward a syncytium triggers macropinocytosis, which is greatly enhanced during amino acid shortage, induced by inhibiting mTOR signaling. Moreover, inhibiting mTOR in pregnant mice markedly stimulates macropinocytosis in the syncytium. Blocking macropinocytosis worsens the phenotypes of fetal growth restriction caused by mTOR-inhibition. Consistently, placentas derived from fetal growth restriction patients display: 1) Repressed mTOR signaling, 2) increased syncytialization, and 3) enhanced macropinocytosis. Together, our findings suggest that the unique ability of STB to undergo macropinocytosis serves as an essential adaptation to the cellular nutrient status, and support fetal survival and growth under nutrient deprivation.