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Reduction of carbon dioxide (CO2) by renewable electricity to produce multicarbon chemicals, such as ethylene (C2H4), continues to be a challenge because of insufficient Faradaic efficiency, low production rates, and complex mechanistic pathways. Here, we report that the rate-determining steps (RDS) on common copper (Cu) surfaces diverge in CO2 electroreduction, leading to distinct catalytic performances. Through a combination of experimental and computational studies, we reveal that CâC bond-making is the RDS on Cu(100), whereas the protonation of *CO with adsorbed water becomes rate-limiting on Cu(111) with a higher energy barrier. On an oxide-derived Cu(100)-dominant Cu catalyst, we reach a high C2H4 Faradaic efficiency of 72%, partial current density of 359 mA cm-2, and long-term stability exceeding 100 h at 500 mA cm-2, greatly outperforming its Cu(111)-rich counterpart. We further demonstrate constant C2H4 selectivity of >60% over 70 h in a membrane electrode assembly electrolyzer with a full-cell energy efficiency of 23.4%.
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An independent set (IS) is a set of vertices in a graph such that no edge connects any two vertices. In adiabatic quantum computation [E. Farhi, et al., Science 292, 472-475 (2001); A. Das, B. K. Chakrabarti, Rev. Mod. Phys. 80, 1061-1081 (2008)], a given graph G(V, E) can be naturally mapped onto a many-body Hamiltonian [Formula: see text], with edges [Formula: see text] being the two-body interactions between adjacent vertices [Formula: see text]. Thus, solving the IS problem is equivalent to finding all the computational basis ground states of [Formula: see text]. Very recently, non-Abelian adiabatic mixing (NAAM) has been proposed to address this task, exploiting an emergent non-Abelian gauge symmetry of [Formula: see text] [B. Wu, H. Yu, F. Wilczek, Phys. Rev. A 101, 012318 (2020)]. Here, we solve a representative IS problem [Formula: see text] by simulating the NAAM digitally using a linear optical quantum network, consisting of three C-Phase gates, four deterministic two-qubit gate arrays (DGA), and ten single rotation gates. The maximum IS has been successfully identified with sufficient Trotterization steps and a carefully chosen evolution path. Remarkably, we find IS with a total probability of 0.875(16), among which the nontrivial ones have a considerable weight of about 31.4%. Our experiment demonstrates the potential advantage of NAAM for solving IS-equivalent problems.
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Scarce and expensive iridium oxide is still the cornerstone catalyst of polymer-electrolyte membrane electrolyzers for green hydrogen production because of its exceptional stability under industrially relevant oxygen evolution reaction (OER) conditions. Earth-abundant transition metal oxides used for this task, however, show poor long-term stability. We demonstrate here the use of nitrogen-doped cobalt oxide as an effective iridium substitute. The catalyst exhibits a low overpotential of 240 mV at 10 mA cm-2 and negligible activity decay after 1000 h of operation in an alkaline electrolyte. Incorporation of nitrogen dopants not only triggers the OER mechanism switched from the traditional adsorbate evolution route to the lattice oxygen oxidation route but also achieves oxygen nonbonding (ONB) states as electron donors, thereby preventing structural destabilization. In a practical anion-exchange membrane water electrolyzer, this catalyst at anode delivers a current density of 1000 mA cm-2 at 1.78 V and an electrical efficiency of 47.8 kW-hours per kilogram hydrogen.
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ConspectusLow-temperature ion-exchange membrane hydrogen fuel cells, as zero-emission power sources, can largely preserve the merits of gasoline engines, including rapid fueling, extended cruising range, and low maintenance cost. To enable the widespread prevalence of fuel-cell automobiles, the U.S. Department of Energy (DOE) has set a long-term fuel-cell system cost target of US$30 kW-1. Over past decades, proton-exchange membrane fuel cell (PEMFC) technology has developed rapidly, resulting in the first commercial sales of fuel-cell-powered vehicles. Although there has been great success, the mass market penetration of PEMFCs is currently hindered by the excessive reliance on expensive platinum group metal (PGM) catalysts. Anion-exchange membrane fuel cells (AEMFCs), because of the alkaline environment that permits the use of PGM-free catalysts, have become an alternative technology with inherent long-term cost advantages. Thus far, significant progress has been made in the exploration of PGM-free catalysts for the oxygen reduction reaction at the AEMFC cathode, some of which have shown intrinsic catalytic properties comparable to PGM catalysts. However, the development of PGM-free catalysts for the anodic hydrogen oxidation reaction (HOR) has lagged behind, presumably owing to its sluggish kinetics in alkali. In alkaline media, the HOR kinetics is about 2 orders of magnitude slower than that in acid, which demands higher PGM loadings to reach similar fuel-cell performance in PEMFCs. Since Raney nickel (Ni) was explored for alkaline HOR catalysis in 1960s, research on Ni-based HOR catalysts has begun and now is flourishing, primarily thanks to their favorable adsorption energies of key HOR intermediates (e.g., Ni-Had and Ni-OHad). At present, a number of strategies have been developed to improve HOR performances of Ni-based materials, such as alloying, Ni nitridation, and alloy amorphization, which yield cost-effective HOR catalysts that rival or even exceed the activity and stability of PGM counterparts.In this Account, we describe our recent research endeavors toward the development of efficient Ni-based HOR catalysts for practical AEMFC anodes. First, we briefly highlight the important merits of AEMFC technology and why Ni-based materials are appealing for alkaline HOR catalysis. Critical innovations in the design of Ni-based nanostructured and bulky catalysts were then discussed, showing their great promise to catalyze alkaline HOR that traditionally relied on PGMs. To demonstrate utility, performances of the elaborately designed Ni-based catalysts under realistic fuel-cell conditions were examined, along with an initial effort to develop a CO-tolerant AEMFC anode. We conclude by outlining future research directions that allow access to next-generation PGM-free HOR catalysts for advanced AEMFCs.
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Diffuse large B-cell lymphoma (DLBCL) is a biologically and clinically heterogeneous disease that requires personalized clinical treatment. Assigning patients to different risk categories and cytogenetic abnormality and genetic mutation groups has been widely applied for prognostic stratification of DLBCL. Increasing evidence has demonstrated that dysregulated metabolic processes contribute to the initiation and progression of DLBCL. Metabolic competition within the tumor microenvironment is also known to influence immune cell metabolism. However, metabolism- and immune-related stratification has not been established. Here, 1660 genes involved in 84 metabolic pathways were selected and tested to establish metabolic clusters (MECs) of DLBCL. MECs established based on independent lymphoma datasets distinguished different survival outcomes. The CIBERSORT algorithm and EcoTyper were applied to quantify the relative abundance of immune cell types and identify variation in cell states for 13 lineages comprising the tumor micro environment among different MECs, respectively. Functional characterization showed that MECs were an indicator of the immune microenvironment and correlated with distinctive mutational characteristics and oncogenic signaling pathways. The novel immune-related MECs exhibited promising clinical prognostic value and potential for informing DLBCL treatment decisions.
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Linfoma Difuso de Grandes Células B , Redes e Vias Metabólicas , Microambiente Tumoral , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/mortalidade , Humanos , Prognóstico , Biomarcadores Tumorais/metabolismo , Feminino , Masculino , Perfilação da Expressão Gênica , MutaçãoRESUMO
Mantle cell lymphoma (MCL) is an uncommon and incurable B-cell lymphoma subtype that has an aggressive course. Hepatitis B virus (HBV) infection has been associated with an increased risk for B-cell lymphomas, and is characterized by distinct clinical and genetic features. Here, we showed that 9.5% of MCL Chinese patients were hepatitis B surface antigen positive (HBsAg+). Compared to HBsAg-negative (HBsAg-) patients, HBsAg+ MCL patients had a greater incidence of elevated lactate dehydrogenase (LDH), but no difference was observed in the other clinical characteristics, including sex, age, ECOG ps, Ann Arbor stage, MIPI, extranodal involvement and Ki-67. The HD-AraC (high-dose cytarabine) regimen was the main first-line induction regimen for younger HBsAg+ patients, and cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) were used for elderly patients. HBsAg seropositivity was associated with a significantly shorter PFS than HBsAg seronegativity when patients were treated with rituximab or CHOP-based regimens. Compared with CHOP, the HD-AraC regimen was associated with longer PFS in HBsAg+ patients. Treatment with a Bruton tyrosine kinase inhibitor (BTKi) alone can also cause HBV reactivation. Among the 74 patients who underwent targeted deep sequencing (TDS), the nonsynonymous mutation load of HBsAg+ MCL patients was greater than that of HBsAg- MCL patients. HDAC1, TRAF5, FGFR4, SMAD2, JAK3, SMC1A, ZAP70, BLM, CDK12, PLCG2, SMO, TP63, NF1, PTPR, EPHA2, RPTOR and FIP1L1 were significantly enriched in HBsAg+ MCL patients.
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Protocolos de Quimioterapia Combinada Antineoplásica , Vírus da Hepatite B , Hepatite B , Linfoma de Célula do Manto , Mutação , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/genética , Idoso , Vírus da Hepatite B/genética , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hepatite B/complicações , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Hepatite B/patologia , Idoso de 80 Anos ou mais , Antígenos de Superfície da Hepatite B/sangue , Vincristina/uso terapêutico , Vincristina/administração & dosagem , Ciclofosfamida/uso terapêutico , Ciclofosfamida/administração & dosagem , Doxorrubicina/uso terapêutico , Doxorrubicina/administração & dosagem , Resultado do TratamentoRESUMO
Numerous studies have highlighted the correlation between metal intake and deteriorated pulmonary function, emphasizing its pivotal role in the progression of Chronic Obstructive Pulmonary Disease (COPD). However, the efficacy of traditional models is often compromised due to overfitting and high bias in datasets with low-level exposure, rendering them ineffective in delineating the contemporary risk trends associated with pulmonary diseases. To address these limitations, we embarked on developing advanced, interpretable models, crucial for elucidating the intricate mechanisms of metal toxicity and enriching the domain knowledge embedded in toxicity models. In this endeavor, we scrutinized extensive, long-term metal exposure datasets from NHANES to explore the interplay between metal and pulmonary functionality. Employing a variety of machine-learning approaches, we opted for the "Mixer of Experts" model for its proficiency in identifying a myriad of toxicological trends and sensitivities. We conceptualized and illustrated the TSAP (Toxicity Score at Population-level), a metal interpretable scoring system offering performance nearly equivalent to the amalgamation of standard interpretable methods addressing the "black box" conundrum. This streamlined, bifurcated procedural analysis proved instrumental in discerning established risk factors, thereby uncovering Tungsten as a novel contributor to COPD risk. SYNOPSIS: TSAP achieved satisfied performance with transparent interpretability, suggesting tungsten intake need further action for COPD prevention.
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Anion-exchange membrane fuel cells provide the possibility to use platinum group metal-free catalysts, but the anodic hydrogen oxidation reaction (HOR) suffers from sluggish kinetics and its source is still debated. Here, over nickel-tungsten (Ni-W) alloy catalysts, we show that the Ni : W ratio greatly governs the HOR performance in alkaline electrolyte. Experimental and theoretical studies unravel that alloying with W can tune the unpaired electrons in Ni, tailoring the potential of zero charge and the catalytic surface to favor hydroxyl adsorption (OHad). The OHad species coordinately interact with potassium (K+) ions, which break the K+ solvation sheath to leave free water molecules, yielding an improved connectivity of hydrogen-bond networks. Consequently, the optimal Ni17W3 alloy exhibits alkaline HOR activity superior to the state-of-the-art platinum on carbon (Pt/C) catalyst and operates steadily with negligible decay after 10,000â cycles. Our findings offer new understandings of alloyed HOR catalysts and will guide rational design of next-generation catalysts for fuel cells.
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Converting hydrogen chemical energy into electrical energy by fuel cells offers high efficiencies and environmental advantages, but ultrapure hydrogen (over 99.97%) is required; otherwise, the electrode catalysts, typically platinum on carbon (Pt/C), will be poisoned by impurity gases such as ammonia (NH3). Here we demonstrate remarkable NH3 resistivity over a nickel-molybdenum alloy (MoNi4) modulated by chromium (Cr) dopants. The resultant Cr-MoNi4 exhibits high activity toward alkaline hydrogen oxidation and can undergo 10,000 cycles without apparent activity decay in the presence of 2 ppm of NH3. Furthermore, a fuel cell assembled with this catalyst retains 95% of the initial peak power density even when NH3 (10 ppm)/H2 was fed, whereas the power output reduces to 61% of the initial value for the Pt/C catalyst. Experimental and theoretical studies reveal that the Cr modifier not only creates electron-rich states that restrain lone-pair electron donation but also downshifts the d-band center to suppress d-electron back-donation, synergistically weakening NH3 adsorption.
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Carbon-carbon coupling electrochemistry on a conventional copper (Cu) catalyst still undergoes low selectivity among many different multicarbon (C2+) chemicals, posing a grand challenge to achieve a single C2+ product. Here, we demonstrate a laser irradiation synthesis of a gerhardtite mineral, Cu2(OH)3NO3, as a catalyst precursor to make a Cu catalyst with abundant stacking faults under reducing conditions. Such structural perturbation modulates electronic microenvironments of Cu, leading to improved d-electron back-donation to the antibonding orbital of *CO intermediates and thus strengthening *CO adsorption. With increased *CO coverage on the defect-rich Cu, we report an acetate selectivity of 56 ± 2% (compared to 31 ± 1% for conventional Cu) and a partial current density of 222 ± 7 mA per square centimeter in CO electroreduction. When run at 400 mA per square centimeter for 40 h in a flow reactor, this catalyst produces 68.3 mmol of acetate throughout. This work highlights the value of a Cu-containing mineral phase in accessing suitable structures for improved selectivity to a single desired C2+ product.
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Regimens based on Bruton's tyrosine kinase inhibitors (BTKi) have been increasingly used to treat mantle cell lymphoma (MCL). A real-world multicenter study was conducted to characterize treatment patterns and outcomes in patients with newly diagnosed MCL by Chinese Hematologist and Oncologist Innovation Cooperation of the Excellent (CHOICE). The final analysis included 1261 patients. Immunochemotherapy was the most common first-line treatment, including R-CHOP in 34%, cytarabine-containing regimens in 21% and BR in 3% of the patients. Eleven percent (n = 145) of the patients received BTKi-based frontline therapy. Seventeen percent of the patients received maintenance rituximab. Autologous hematopoietic stem cell transplantation (AHCT) was conducted in 12% of the younger (<65 years) patients. In younger patients, propensity score matching analysis did not show significant difference in 2-year progression-free survival and 5-year overall survival rate in patients receiving standard high-dose immunochemotherapy followed by AHCT than induction therapy with BTKi-based regimens without subsequent AHCT (72% vs 70%, P = .476 and 91% vs 84%, P = .255). In older patients, BTKi combined with bendamustine plus rituximab (BR) was associated with the lowest POD24 rate (17%) compared with BR and other BTKi-containing regimens. In patients with resolved hepatitis B at the baseline, HBV reactivation rate was 2.3% vs 5.3% in those receiving anti-HBV prophylaxis vs not; BTKi treatment was not associated with higher risk of HBV reactivation. In conclusion, non-HD-AraC chemotherapy combined with BTKi may be a viable therapeutic strategy for younger patients. Anti-HBV prophylaxis should be implemented in patients with resolved hepatitis B.
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Transplante de Células-Tronco Hematopoéticas , Hepatite B , Linfoma de Célula do Manto , Adulto , Humanos , Idoso , Linfoma de Célula do Manto/tratamento farmacológico , Rituximab/uso terapêutico , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica , Citarabina/uso terapêuticoRESUMO
Pattern recognition receptors (PRRs) are plasma membrane-localised proteins that sense molecular patterns to initiate pattern-triggered immunity (PTI). Receptor-like cytoplasmic kinases (RLCKs) function downstream of PRRs to propagate signal transduction via the phosphorylation of substrate proteins. The identification and characterisation of RLCK-regulated substrate proteins are critical for our understanding of plant immunity. We showed that SHOU4 and SHOU4L are rapidly phosphorylated upon various patterns elicitation and are indispensable for plant resistance to bacterial and fungal pathogens. Protein-protein interaction and phosphoproteomic analysis revealed that BOTRYTIS-INDUCED KINASE 1, a prominent protein kinase of RLCK subfamily VII (RLCK-VII), interacted with SHOU4/4L and phosphorylated multiple serine residues on SHOU4L N-terminus upon pattern flg22 treatment. Neither phospho-dead nor phospho-mimic SHOU4L variants complemented pathogen resistance and plant development defect of the loss-of-function mutant, suggesting that reversible phosphorylation of SHOU4L is critical to plant immunity and plant development. Co-immunoprecipitation data revealed that flg22 induced SHOU4L dissociation from cellulose synthase 1 (CESA1) and that a phospho-mimic SHOU4L variant inhibited the interaction between SHOU4L and CESA1, indicating the link between SHOU4L-mediated cellulose synthesis and plant immunity. This study thus identified SHOU4/4L as new components of PTI and preliminarily revealed the mechanism governing SHOU4L regulation by RLCKs.
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Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Reconhecimento da Imunidade Inata , Imunidade Vegetal/fisiologia , Receptores de Reconhecimento de Padrão/metabolismo , Plantas/metabolismo , Celulose/metabolismo , Proteínas de Membrana/metabolismo , Parede Celular/metabolismo , Doenças das PlantasRESUMO
The characterization and manipulation of polarization state at single photon level are of great importance in research fields such as quantum information processing and quantum key distribution, where photons are normally delivered using single mode optical fibers. To date, the demonstrated polarimetry measurement techniques based on a superconducting nanowire single photon detector (SNSPD) require the SNSPD to be either highly sensitive or highly insensitive to the photon's polarization state, therefore placing an unavoidable challenge on the SNSPD's design and fabrication processes. In this article, we present the development of an alternative polarimetry measurement technique, of which the stringent requirement on the SNSPD's polarization sensitivity is removed. We validate the proposed technique by a rigorous theoretical analysis and comparisons of the experimental results obtained using a fiber-coupled SNSPD with a polarization extinction ratio of â¼2 to that obtained using other well-established known methods. Based on the full Stokes data measured by the proposed technique, we also demonstrate that at the single photon level (â¼ -100 dBm), the polarization state of the photon delivered to the superconducting nanowire facet plane can be controlled at will using a further developed algorithm. Note that other than the fiber-coupled SNSPD, the only component involved is a quarter-wave plate (no external polarizer is necessary), which when aligned well has a paid insertion loss less than 0.5â dB.
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Quantum sensing can provide the superior sensitivity for sensing a physical quantity beyond the shot-noise limit. In practice, however, this technique has been limited to the issues of phase ambiguity and low sensitivity for small-scale probe states. Here, we propose and demonstrate a full-period quantum phase estimation approach by adopting the Kitaev's phase estimation algorithm to eliminate the phase ambiguity and using the GHZ states to obtain phase value, simultaneously. For an N-party entangled state, our approach can achieve an upper bound of sensitivity of δθ=sqrt[3/(N^{2}+2N)], which beats the limit of adaptive Bayesian estimation. By performing an eight-photon experiment, we demonstrate the estimation of unknown phases in a full period, and observe the phase superresolution and sensitivity beyond the shot-noise limit. Our Letter provides a new way for quantum sensing and represents a solid step towards its general applications.
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Oxidative bromination has been serving as a powerful tool for the synthesis of bromo-containing molecules, as this bromination strategy features environmental friendliness, high flexibility in reaction system design and wide abundance of bromide sources and oxidants. The past decade has witnessed a large number of efficient oxidative bromination reaction systems and novel brominated aromatics. This review summarizes recent developments in the field of oxidative preparation of bromoarenes and bromoheteroarenes covering from 2012 to 2022.
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BACKGROUND: It is unknown whether high-frequency ultrasound (HFUS) can evaluate invisible subcutaneous lesions. We aimed to investigate the diagnostic value of HFUS in invisible subcutaneous lesions. METHOD: Patients with invisible subcutaneous lesions were prospectively recruited from two centres. Before undergoing biopsy or surgery, each lesion was independently evaluated by two clinicians. One provides a clinical diagnosis by only clinical examination and the other provides an integrated diagnosis by combining clinical examination and HFUS information. Diagnoses were classified as correct, wrong, and indeterminate. A total of 391 lesions from 355 patients were enrolled, including 225 epidermoid cysts, 77 lipomas, 25 pilomatrixomas, 21 haemangiomas, 19 dermatofibromas, 11 dermatofibrosarcoma protuberans (DFSP), 7 neurofibromas, and 6 leiomyomas. Using pathological results as the gold standard, diagnostic performance was compared. RESULTS: The number of correct diagnoses increased from 185 (47.3%) by clinical examination alone to 316 (80.8%) after the addition of HFUS (P < 0.05). Meanwhile, the indeterminate diagnosis rate decreased from 143 (36.6%) to 10 (2.6%). Using HFUS, the accuracy improved significantly for epidermoid cysts (59.6% vs. 86.7%), lipomas (50.6% vs. 94.8%), pilomatrixomas (0% vs. 48.0%), haemangiomas (23.8% vs. 57.1%), and DFSPs (0% vs. 81.8%) (all p < 0.05). However, HFUS did not significantly improve the diagnostic accuracy of dermatofibromas (15.8% vs. 21.1%, p > 0.999), neurofibromas (42.9% vs. 71.4%, p = 0.625), or leiomyomas (16.7% vs. 100%, p = 0.063). CONCLUSION: Combining HFUS and clinical examination can generally improve the diagnostic accuracy and decrease the indeterminacy of invisible subcutaneous lesions, especially epidermoid cysts, lipomas, pilomatrixomas, haemangiomas, and DFSPs. However, for some rare lesions, HFUS cannot provide useful information.
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Cisto Epidérmico , Doenças do Cabelo , Hemangioma , Histiocitoma Fibroso Benigno , Leiomioma , Lipoma , Neurofibroma , Pilomatrixoma , Neoplasias Cutâneas , Humanos , Cisto Epidérmico/diagnóstico por imagem , Hemangioma/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagemRESUMO
Short non-coding RNA molecules (sRNAs) play a fundamental role in gene regulation and development in higher organisms. They act as molecular postcodes and guide AGO proteins to target nucleic acids. In plants, sRNA-targeted mRNAs are degraded, reducing gene expression. In contrast, sRNA-targeted DNA sequences undergo cytosine methylation referred to as RNA-directed DNA methylation (RdDM). Cytosine methylation can suppress transcription, thus sRNAs are potent regulators of gene expression. sRNA-mediated RdDM is involved in genome stability through transposon silencing, mobile signalling for epigenetic gene control and hybrid vigour. Since cytosine methylation can be passed on to subsequent generations, RdDM contributes to transgenerational inheritance of the epigenome. Using a novel approach, which can differentiate between primary (inducer) and secondary (amplified) sRNAs, we show that initiation of heritable RdDM does not require complete sequence complementarity between the sRNAs and their nuclear target sequences. sRNAs with up to four regularly interspaced mismatches are potent inducers of RdDM, however, the number and disruptive nature of nucleotide polymorphisms negatively correlate with their efficacy. Our findings contribute to understanding how sRNA can directly shape the epigenome and may be used in designing the next generation of RNA silencing constructs.
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Interferência de RNA , Pequeno RNA não Traduzido/química , Metilação de DNA , Genes Homeobox , Vírus de Plantas/genética , Plantas Geneticamente Modificadas , Nicotiana/genéticaRESUMO
BACKGROUND: This study aimed to conduct a case-control study of endoscopic and fluoroscopic metal stent placement combined with laparoscopic surgery versus conventional open Hartmann's procedure in treating acute left-sided colon cancer obstruction. Additionally, the study aims to discuss the application value of endoscopic and X-ray-guided metal stent placement combined with laparoscopic surgery in the treatment of acute left-sided colon cancer obstruction. METHODS: From June 2011 to December 2019, 23 patients with acute left-sided colon cancer obstruction who underwent metal stent implantation combined with laparoscopic surgery under endoscopy and X-ray fluoroscopy in Wenzhou Central Hospital were collected, and 20 patients with acute left-sided colon cancer obstruction who underwent traditional emergency open Hartmann's surgery during the same period were selected as a control group. All patients were diagnosed with left colon obstruction by plain abdominal film and/or CT before the operation and colon adenocarcinoma by colonoscopic biopsy and/or postoperative pathology. The operation time, intraoperative blood loss, postoperative anal exhaust time, the success rate of one-stage anastomosis, postoperative hospital stay, and postoperative complications were compared between the two groups. RESULTS: This study showed a significant difference in the therapeutic effect between the two groups. Compared with the traditional Hartmann's operation group, the success rate of one-stage anastomosis in endoscopic and X-ray-guided metal stent placement combined with the laparoscopic operation group was significantly higher than that in the Hartmann's operation group (P < 0.05). The overall incidence of postoperative complications and hospital stay were significantly lower in the observation group than in the Hartmann's group (P < 0.05). Further subgroup analysis of the overall postoperative complication rate of the two groups showed that the traditional Hartmann's operation group was more likely to have an incomplete intestinal obstruction (P < 0.05). This study also showed no significant differences between the two groups in operation time, intraoperative blood loss, number of harvested lymph nodes, and postoperative anal exhaust time (all P > 0.05). This study also found no significant differences between the two groups in overall survival rates or recurrence-free survival rates (all P > 0.05). CONCLUSIONS: The comparison of the therapeutic effects of the two groups verified the feasibility of endoscopy combined with X-ray fluoroscopy metal stent placement in combination with laparoscopic surgery in the treatment of acute left-sided colon cancer obstruction. Compared with the traditional emergency open Hartmann's procedure, metal stent implantation under endoscopy and X-ray fluoroscopy combined with laparoscopic surgery is more minimally invasive, safe, and effective. It avoids the traditional second or even third surgical trauma to effectively improve the quality of life of patients, so that patients can recover quickly after surgery.
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Adenocarcinoma , Neoplasias do Colo , Obstrução Intestinal , Laparoscopia , Humanos , Neoplasias do Colo/cirurgia , Adenocarcinoma/cirurgia , Estudos de Casos e Controles , Qualidade de Vida , Raios X , Resultado do Tratamento , Estudos Retrospectivos , Laparoscopia/métodos , Colostomia/efeitos adversos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Complicações Pós-Operatórias/epidemiologia , Anastomose Cirúrgica/métodos , Endoscópios/efeitos adversos , Fluoroscopia/efeitos adversos , Stents/efeitos adversosRESUMO
Picturing the atomic migration pathways of catalysts in a reactive atmosphere is of central significance for uncovering the underlying catalytic mechanisms and directing the design of high-performance catalysts. Here, we describe a reduction-controlled atomic migration pathway that converts nanoparticles to single atom alloys (SAAs), which has remained synthetically challenging in prior attempts due to the elusive mechanism. We achieved this by thermally treating the noble-metal nanoparticles M (M = Ru, Rh, Pd, Ag, Ir, Pt, and Au) on metal oxide (CuO) supports with H2/Ar. Atomic-level characterization revealed such conversion as the synergistic consequence of noble metal-promoted H2 dissociation and concomitant CuO reduction. The observed atomic migration pathway offers an understanding of the dynamic mechanisms study of nanomaterials formation and catalyst design.
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Ligas , Nanopartículas Metálicas , CatáliseRESUMO
This study aims to investigate the intervention effect of the aqueous extract of Epimedium sagittatum Maxim on the mouse model of bleomycin(BLM)-induced pulmonary fibrosis, so as to provide data support for the clinical treatment of pulmonary fibrosis. Ninety male C57BL/6N mice were randomized into normal(n=10), model(BLM, n=20), pirfenidone(PFD, 270 mg·kg~(-1), n=15), and low-, medium-, and high-dose E. sagittatum extract(1.67 g·kg~(-1), n=15; 3.33 g·kg~(-1), n=15; 6.67 g·kg~(-1), n=15) groups. The model of pulmonary fibrosis was established by intratracheal instillation of BLM(5 mg·kg~(-1)) in the other five groups except the normal group, which was treated with an equal amount of normal saline. On the day following the modeling, each group was treated with the corresponding drug by gavage for 21 days. During this period, the survival rate of the mice was counted. After gavage, the lung index was calculated, and the morphology and collagen deposition of the lung tissue were observed by hematoxylin-eosin(HE) and Masson staining, respectively. The levels of reactive oxygen species(ROS) in lung cell suspensions were measured by flow cytometry. The levels of glutathione peroxidase(GSH-Px), total superoxide dismutase(T-SOD), and malondialdehyde(MDA) the in lung tissue were measured. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling(TUNEL) was employed to examine the apoptosis of lung tissue cells. The content of interleukin-6(IL-6), chemokine C-C motif ligand 2(CCL-2), matrix metalloproteinase-8(MMP-8), transforming growth factor-beta 1(TGF-ß1), alpha-smooth muscle actin(α-SMA), E-cadherin, collagen â , and fibronectin in the lung tissue was measured by enzyme-linked immunosorbent assay(ELISA). The expression levels of F4/80, Ly-6G, TGF-ß1, and collagen â in the lung tissue were determined by immunohistochemistry. The mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue were determined by qRT-PCR. The content of hydroxyproline(HYP) in the lung tissue was determined by alkaline hydrolysation. The expression of α-SMA and E-cadherin was detected by immunofluorescence, and the protein levels of α-SMA, vimentin, E-cadherin in the lung tissue were determined by Western blot. The results showed the aqueous extract of E. sagittatum increased the survival rate, decreased the lung index, alleviated the pathological injury, collagen deposition, and oxidative stress in the lung tissue, and reduced the apoptotic cells. Furthermore, the aqueous extract of E. sagittatum down-regulated the protein levels of F4/80 and Ly-6G and the mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue, reduced the content of IL-6, CCL-2, and MMP-8 in the alveolar lavage fluid. In addition, it lowered the levels of HYP, TGF-ß1, α-SMA, collagen â , fibronectin, and vimentin, and elevated the levels of E-cadherin in the lung tissue. The aqueous extract of E. sagittatum can inhibit collagen deposition, alleviate oxidative stress, and reduce inflammatory response by regulating the expression of the molecules associated with epithelial-mesenchymal transition, thus alleviating the symptoms of bleomycin-induced pulmonary fibrosis in mice.