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In a recent issue of Molecular Cell, Kretov et al. (2020) demonstrate that microRNA-144 targets Dicer in a negative feedback loop, affecting global canonical microRNA expression in erythrocytes. MicroRNA-451 is refractory to the loss of Dicer because of its Ago2-dependent processing.
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MicroRNAs , Proteínas Argonautas , Eritropoese , Ribonuclease IIIRESUMO
BACKGROUND: The ligamentum flavum (LF) is an important anatomical structure of the spine. Ossification of the LF (OLF) has become the leading cause of thoracic spinal stenosis. Circular RNAs (circRNAs) and N6-methyladenosine (m6A) modification are reported to be associated with several human diseases. However, the role of circRNAs and m6A modification in the pathogenesis of OLF has not been fully investigated. Here, we aimed to explore the vital function of circRNAs and m6A modification in OLF. MATERIALS AND METHODS: We analysed the circRNA expression of 4 OLF tissues and 4 normal LF tissues using bioinformatic analysis and identified circCDK14 for further analysis. We investigated the effects of circCDK14 on the osteogenic differentiation of LF cells. We observed that circCDK14 regulated its target genes by binding to miRNAs as a miRNA sponge. Moreover, the circRNA pull-down assay indicated that RNA-binding proteins might regulate the expression of circCDK14 via m6A modification. RESULTS: CircCDK14 was significantly upregulated in OLF tissues compared to normal LF tissues. Overexpression of circCDK14 promoted the osteogenic differentiation of LF cells. Mechanistically, CircCDK14 promoted the expression of ALF transcription elongation Factor 4 (AFF4) by serving as a sponge for miR-93-5p. Moreover, Wilms tumour 1-associated protein (WTAP) increased the stability of circCDK14 via N6-methyladenosine modification. CONCLUSION: The m6A-modified CircCDK14 binding to miR-93-5p played an important role in the osteogenesis of LF cells by targeting AFF4, providing a promising therapeutic target for OLF.
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Adenosina , Diferenciação Celular , Epigênese Genética , Ligamento Amarelo , MicroRNAs , Osteogênese , RNA Circular , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Ligamento Amarelo/metabolismo , Ligamento Amarelo/patologia , Osteogênese/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Diferenciação Celular/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genéticaRESUMO
Single-cell studies have delineated cellular diversity and uncovered increasing numbers of previously uncharacterized cell types in complex tissues. Thus, synthesizing growing knowledge of cellular characteristics is critical for dissecting cellular heterogeneity, developmental processes and tumorigenesis at single-cell resolution. Here, we present Cell Taxonomy (https://ngdc.cncb.ac.cn/celltaxonomy), a comprehensive and curated repository of cell types and associated cell markers encompassing a wide range of species, tissues and conditions. Combined with literature curation and data integration, the current version of Cell Taxonomy establishes a well-structured taxonomy for 3,143 cell types and houses a comprehensive collection of 26,613 associated cell markers in 257 conditions and 387 tissues across 34 species. Based on 4,299 publications and single-cell transcriptomic profiles of â¼3.5 million cells, Cell Taxonomy features multifaceted characterization for cell types and cell markers, involving quality assessment of cell markers and cell clusters, cross-species comparison, cell composition of tissues and cellular similarity based on markers. Taken together, Cell Taxonomy represents a fundamentally useful reference to systematically and accurately characterize cell types and thus lays an important foundation for deeply understanding and exploring cellular biology in diverse species.
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Nanoparticles (NPs) inevitably interact with proteins upon exposure to biological fluids, leading to the formation of an adsorption layer known as the "protein corona". This corona imparts NPs with a new biological identity, directly influencing their interactions with living systems and dictating their fates in vivo. Thus, gaining a comprehensive understanding of the dynamic interplay between NPs and proteins in biological fluids is crucial for predicting therapeutic effects and advancing the clinical translation of nanomedicines. Numerous methods have been established to decode the protein corona fingerprints. However, these methods primarily rely on prior isolation of NP-protein complex from the surrounding medium by centrifugation, resulting in the loss of outer-layer proteins that directly interact with the biological system and determine the in vivo fate of NPs. We discuss here separation techniques as well as in situ characterization methods tailored for comprehensively unraveling the inherent complexities of NP-protein interactions, highlighting the challenges of in situ protein corona characterization and its significance for nanomedicine development and clinical translation.
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The formation of a protein corona gives nanomedicines a distinct biological identity, profoundly influencing their fate in the body. Nonspecific nanoparticle-protein interactions are typically highly heterogeneous, which can lead to unique biological behaviors and in vivo fates for individual nanoparticles that remain underexplored. To address this, we have established an in situ approach that allows quantitative examination of nanoparticle-protein adsorption at the individual nanoparticle level. This method integrates dual fluorescence quantification techniques, wherein the nanoparticles are first individually analyzed via nanoflow cytometry to detect fluorescent signals from adsorbed proteins. The obtained fluorescence intensity is then translated into protein quantities through calibration with microplate reader quantification. Consequently, this approach enables analysis of interparticle heterogeneity of nano-protein interactions, as well as in situ monitoring of protein adsorption kinetics and nanoparticle aggregation status in blood serum, preconditioning for a comprehensive understanding of nano-bio interactions, and predicting in vivo fate of nanomedicines.
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Proteínas Sanguíneas , Nanopartículas , Adsorção , Nanopartículas/química , Proteínas Sanguíneas/química , Proteínas Sanguíneas/análise , Humanos , Coroa de Proteína/química , Fluorescência , CinéticaRESUMO
Gene transcription and protein translation are two key steps of the 'central dogma.' It is still a major challenge to quantitatively deconvolute factors contributing to the coding ability of transcripts in mammals. Here, we propose ribosome calculator (RiboCalc) for quantitatively modeling the coding ability of RNAs in human genome. In addition to effectively predicting the experimentally confirmed coding abundance via sequence and transcription features with high accuracy, RiboCalc provides interpretable parameters with biological information. Large-scale analysis further revealed a number of transcripts with a variety of coding ability for distinct types of cells (i.e. context-dependent coding transcripts), suggesting that, contrary to conventional wisdom, a transcript's coding ability should be modeled as a continuous spectrum with a context-dependent nature.
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Modelos Biológicos , Biossíntese de Proteínas , RNA , Transcrição Gênica , Animais , Genoma Humano , Humanos , Mamíferos/genética , Mamíferos/metabolismo , RNA/metabolismo , RNA Longo não Codificante/genética , Ribossomos/genética , Ribossomos/metabolismo , Transcrição Gênica/genéticaRESUMO
In the landscape of infectious diseases, human coronaviruses such as SARS-CoV, MERS-CoV, and SARS-CoV-2 pose significant threats, characterized by severe respiratory illnesses and notable resistance to conventional treatments due to their rapid evolution and the emergence of diverse variants, particularly within SARS-CoV-2. This study investigated the development of broad-spectrum coronavirus vaccines using heterodimeric RBD-Fc proteins engineered through the "Knob-into-Hole" technique. We constructed various recombinant proteins incorporating the receptor-binding domains (RBDs) of different coronaviruses. Heterodimers combining RBDs from SARS-CoV-2 with those of SARS-CoV or MERS-CoV elicited superior neutralizing responses compared to homodimeric proteins in murine models. Additionally, heterotetrameric proteins, specifically D614G_Delta/BA.1_XBB.1.5-RBD and MERS_D614G/BA.1_XBB.1.5-RBD, elicited remarkable breadth and potency in neutralizing all known SARS-CoV-2 variants, SARS-CoV, related sarbecoviruses like GD-Pangolin and WIV1, and even MERS-CoV pseudoviruses. Furthermore, these heterotetrameric proteins also demonstrated enhanced cellular immune responses. These findings underscore the potential of recombinant hetero proteins as a universal vaccine strategy against current and future coronavirus threats.
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Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Camundongos , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/química , Vacinas contra COVID-19/imunologia , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Fragmentos Fc das Imunoglobulinas/imunologia , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/química , COVID-19/prevenção & controle , COVID-19/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Camundongos Endogâmicos BALB C , Feminino , Domínios Proteicos , Testes de Neutralização , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genéticaRESUMO
BACKGROUND: Skin fibrosis is the most typical pathological manifestation of systemic sclerosis (SSc) and localized scleroderma (LS) with unclear etiology and few effective treatments. Though excessive collagen secretion by fibroblasts is the primary cause of skin fibrosis, many lines of evidence suggested that vascular damage was the initiating event and various cell types along with fibroblasts worked together to contribute to the pathogenesis of skin fibrosis. OBJECTIVES: We sought to explore the relationships between vascular endothelial cell lesions and immune cell infiltration, along with the cell-cell interactions among various cell types within the fibrotic skin ecosystem. METHODS: Single-cell RNA-seq (10x Genomics) was performed on skin biopsies of 3 healthy donors and 7 SSc patients in Chinese. The additional 3 localized scleroderma patients' data from NCBI database (GSE160536) were integrated by Harmony. CellChat package (v1.5.0) was applied to analyze cell communication network. Transwell assay and subcutaneous bleomycin (BLM) injection in mice were used to explore the role of ACKR1 on immune cell infiltration. Milo single-cell western blot was applied to show the activation of fibroblast subclusters. RESULTS: A total of 62,295 cells were obtained and subpopulations of stromal and immune cells were identified. Interaction network analysis revealed that multiple chemokines secreted by macrophages, pericytes, and pro-inflammatory fibroblasts could bind with Duffy antigen/receptor for chemokines (ACKR1), which is highly expressed on ACKR1+ endothelial cells of lesion skin. Transwell assay revealed that over-expressed ACKR1 in HUVEC facilitated leukocyte infiltration under the treatment of IL8. The BLM mice showed enhanced ACKR1 expression, massive immune cell infiltration, and fibrosis in skin, which could be attenuated by ACKR1 inhibition. Furthermore, infiltrated macrophages with TGFB1 or PDGFB high production could activate SFRP2/ASPN+ fibroblasts to contribute to excessive accumulation of extracellular matrix (ECM), and the SOX4-ASPN axis plays an important role in the TGF-ß signaling cascade and the etiology of skin fibrosis. CONCLUSIONS: Our results reveal that highly expressed ACKR1 in endothelial cells of fibrotic skin tissue promotes immune cell infiltration, and SFRP2/ASPN+ fibroblasts synergize to exacerbate skin fibrosis.
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Developing adsorbent materials for the efficient removal of multiple organic pollutants in water is of importance technological significance. In the present work, a kind of conjugated microporous polymer (CMP) with a hollow sphere structure was constructed by applying SiO2 nanoparticles as a template and 1,3,5-triethynylbenzene (TEB) and 2,7-dibromocarbazole (27-DBCZ) as building blocks via the Sonogashira-Hagihara cross-coupling reaction. In order to further improve the dispersibility of the as-resulting CMPs in water, hydrophilic CMPs (H-S-CMPs) were obtained by a sulfonation modification. The adsorption performance of H-S-CMPs on dyes and antibiotics was investigated, which was based on different experimental parameters such as the initial concentration, contact time, temperature, pH, and adsorbent dose. The adsorption isotherm, kinetics, and thermodynamics were also studied, and the possible adsorption mechanism of H-S-CMPs was discussed. The experimental results illustrated that the adsorption process of H-S-CMPs on dyes and antibiotics is more consistent with the Langmuir isotherm model and the pseudo-second-order kinetic model. The maximum adsorption capacities of H-S-CMPs for rhodamine B (RhB), methylene blue (MB), ciprofloxacin, and norfloxacin were 206.2, 324.7, 222.2, and 216.9 mg/g, respectively, which were determined according to the Langmuir isothern model. In addition, the adsorption mechanism of H-S-CMPs may be attributed to the synergistic effects of hydrogen bonding, electrostatic attraction, π-π stacking, and pore filling. After 5 cycles, H-S-CMPs still maintained good stability, and their removal rate of dyes could reach more than 70%. Notably, this polymeric hollow microsphere has been less extensively investigated as an adsorbent for the removal of dyes and antibiotics. As a result, based on the designable flexibility of CMPs and the unique structure of hollow microspheres, the material holds great promise for wastewater treatment in the presence of multiple pollutants.
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Water is the lifeblood of everything on earth, nourishing and nurturing all forms of life, while also contributing to the development of civilization. However, with the rapid development of economic construction, especially the accelerated process of modern industrialization, the pollution of oily sewage is becoming increasingly serious, affecting the ecological balance and human health. The efficient elimination of pollutants in sewage is, therefore, particularly urgent. In this paper, a core-shell microbial reactor (MPFA@CNF-SA-AM) was fabricated by using nanocellulose and sodium alginate (SA) particles embedded with microorganisms as the core and lipophilic and hydrophobic fly ash as the outer shell layer. Compared with that of free microorganisms and cellulose and SA aerogel pellets loading with microorganisms (CNF-SA-AM), which has a degradation efficiency of 60.69 and 82.89%, respectively, the MPFA@CNF-SA-AM possesses a highest degradation efficiency of 90.60% within 240 h. So that this self-floating microbial reactor has selective adsorption properties to achieve oil-water separation in oily wastewater and high effective degradation of organic pollutants with low cost. The adsorption curves of MPFA@CNF-SA-AM for diesel and n-hexadecane were studied. The results showed that the adsorption follows the Freundlich model and is a multimolecular layer of physical adsorption. In addition, the degradation mechanism of diesel oil was studied by gas chromatography-mass spectrometry. The results showed that diesel oil was selectively adsorbed to the interior of MPFA@CNF-SA-AM, and it was degraded by enzymes in microorganisms into n-hexadecanol, n-hexadecaldehyde, and n-hexadecanoic acid in turn, and finally converted to water and carbon dioxide. Compared with existing oily wastewater treatment methods, this green and pollution-free dual-functional core-shell microbial reactor has the characteristics of easy preparation, high efficiency, flexibility, and large-scale degradation. It provides a new, effective green choice for oily wastewater purification and on-site oil spill accidents.
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Águas Residuárias , Adsorção , Águas Residuárias/química , Poluentes Químicos da Água/química , Alginatos/química , Celulose/química , Óleos/química , Biodegradação Ambiental , Polímeros/químicaRESUMO
OBJECTIVES: To determine the relationship between renal tumor complexity and vascular complications after partial nephrectomy using PADUA, RENAL, and ZS scores. METHODS: Between January 2007 and December 2018, a total of 1917 patients with available cross-sectional imaging were enrolled in the study. Logistic regressions were used to identify independent predictors of vascular complications. RESULTS: Of 1917 patients, 31 (1.6%) developed vascular complications, including 10 females and 21 males. The high-complexity category was significantly associated with a decreased risk of vascular complication in PADUA (OR = 0.256; 95%CI = 0.086-0.762; P = 0.014) and ZS score (OR = 0.279; 95%CI = 0.083-0.946; P = 0.040). Laparoscopic partial nephrectomy and robot-assisted laparoscopic partial nephrectomy were independent risk factors for vascular complications. Meanwhile, the incidence was significantly reduced in the recent 4 years in the high score tumor group alone in PADUA (0.2% [1/474] vs. 2.2% [3/139], P = 0.038) and ZS score (0.2% [1/469] vs. 2.7% [3/112], P = 0.024). In the first 8 years, laparoscopic partial nephrectomy and robot-assisted laparoscopic partial nephrectomy were the only two independent risk factors for vascular complications. In the recent 4 years, only the high-complexity category was significantly associated with a decreased risk of vascular complication in the PADUA score (OR = 0.110; 95%CI = 0.013-0.938; P = 0.044). CONCLUSION: The renal anatomic classification system cannot predict the occurrence of vascular complications after partial nephrectomy.
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Neoplasias Renais , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Masculino , Feminino , Humanos , Rim/cirurgia , Nefrectomia/efeitos adversos , Nefrectomia/métodos , Neoplasias Renais/patologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: This study aimed to investigate the association between iron content in grey matter (GM) nuclei and functional outcome in acute ischaemic stroke (AIS) patients utilizing quantitative susceptibility mapping. METHODS: Forty AIS patients and 40 age-, sex- and education-matched healthy controls underwent quantitative susceptibility mapping to assess susceptibility values, which are positively correlated with iron content, in the caudate nucleus, putamen, globus pallidus, thalamus, red nucleus and substantia nigra. The nuclei on the contralateral side were measured in AIS patients to minimize confounding due to oedema or haemorrhage. Functional outcome was determined by the modified Rankin Scale (mRS) score at 3 months after stroke. Poor outcome was defined as mRS >2, whilst a good outcome was defined as ≤2. RESULTS: Susceptibility values were significantly higher in most contralateral GM nuclei in AIS patients than in the corresponding left or right nuclei in healthy controls. AIS patients with poor outcome showed significantly lower susceptibility value than those with good outcome in the contralateral caudate nucleus, but no significant differences were observed in other GM nuclei. Binary logistic regression analysis revealed a significant association between the susceptibility value of the contralateral caudate nucleus and poor outcome after adjustment for confounders (adjusted odds ratio 0.692, 95% confidence interval 0.486-0.986, p = 0.042). Receiver operating characteristic curve analysis showed an acceptable ability of the susceptibility value of the contralateral caudate nucleus to predict poor outcome (area under the curve 0.740, p = 0.013). CONCLUSIONS: Lower iron content in the contralateral caudate nucleus was associated with poor functional outcome in AIS patients.
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OBJECTIVE AND DESIGN: Changes in the immune status of patients with sepsis may have a major impact on their prognosis. Our research focused on changes in various immune cell subsets and T-cell activation during the progression of sepsis. METHODS AND SUBJECTS: We collected data from 188 sepsis patients at the First Affiliated Hospital of Zhejiang University School of Medicine. The main focus was on the patient's immunocyte subset typing, T-cell activation/Treg cell analysis, and cytokine assay, which can indicate the immune status of the patient. RESULTS: The study found that the number of CD4+ T cells, CD8+ T cells, NK cells, and B cells decreased early in the disease, and the decrease in CD4+ and CD8+ T cells was more pronounced in the death group. T lymphocyte activation was inhibited, and the number of Treg cells increased as the disease progressed. T lymphocyte inhibition was more significant in the death group, and the increase in IL-10 was more significant in the death group. Finally, we used patients' baseline conditions and immunological detection indicators for modeling and found that IL-10, CD4+ Treg cells, CD3+HLA-DR+ T cells, and CD3+CD69+ T cells could predict patients' prognosis well. CONCLUSION: Our study found that immunosuppression occurs in patients early in sepsis. Early monitoring of the patient's immune status may provide a timely warning of the disease.
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Citocinas , Sepse , Humanos , Citocinas/metabolismo , Interleucina-10/metabolismo , Linfócitos T CD8-Positivos , Ativação Linfocitária , Linfócitos T Reguladores , Sepse/metabolismo , Subpopulações de Linfócitos TRESUMO
ABSTRACT: Clinical practice shows that a critical unmet need in the field of thrombosis prevention is the availability of anticoagulant therapy without bleeding risk. Inhibitors against FXIa or FXIIa have been extensively studied because of their low bleeding risk. However, whether these compounds produce synergistic effects has not yet been explored. In this study, analyses of activated partial thromboplastin time in combination with the FXIa inhibitor PN2KPI and the FXIIa inhibitor Infestin4 at different proportions were performed using the SynergyFinder tool identifying synergistic anticoagulation effects. Both an FeCl 3 -induced carotid artery thrombosis mouse model and a transient occlusion of the middle cerebral artery mouse model showed that the combination of PN2KPI and Infestin4, which are 28.57% and 6.25% of the effective dose, respectively, significantly prevents coagulation, and furthermore, dual inhibition does not cause bleeding risk.
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Anticoagulantes , Coagulação Sanguínea , Modelos Animais de Doenças , Sinergismo Farmacológico , Fator XIIa , Fator XIa , Animais , Fator XIa/antagonistas & inibidores , Fator XIa/metabolismo , Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Masculino , Fator XIIa/antagonistas & inibidores , Fator XIIa/metabolismo , Trombose das Artérias Carótidas/prevenção & controle , Trombose das Artérias Carótidas/induzido quimicamente , Trombose das Artérias Carótidas/tratamento farmacológico , Camundongos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Hemorragia/induzido quimicamente , Camundongos Endogâmicos C57BL , Tempo de Tromboplastina ParcialRESUMO
OBJECTIVE: Thromboangiitis obliterans (TAO) remains clinical challenging due to its rarity and underwhelming management outcomes. This study aimed to describe a novel TAO rabbit model that demonstrates a closer resemblance to TAO. METHODS: Thirty-six New Zealand rabbits underwent the surgical implantation of calibrated gelatin sponge particles (CGSPs) into their right femoral artery. The CGSPs were soaked in different solutions to simulate different types of thrombi: normal (NT; normal saline); inflammatory TAO thrombus (TAO; dimethylsulfoxide [DMSO]), and DMSO with methotrexate (MTX). All groups underwent clinical assessment, digital subtraction angiography (DSA) and histopathological analysis at time points day 0 (immediate), week 1 (acute), week 2 (subacute), and week 4 (chronic). RESULTS: The TAO rabbit presented with signs of ischemia of the right digit at week 4. On DSA, the TAO rabbits exhibited formation of corkscrew collaterals starting week 1. On H&E staining, gradual CGSP degradation was observed along with increased red blood cell aggregation and inflammatory cells migration in week 1. On week 2, disorganization of the tunica media layer and vascular smooth muscle cell (VSMC) proliferation was observed. In the TAO rabbit, migrated VSMCs, inflammatory cells, and extracellular matrix with collagen-like substances gradually occluded the lumen. On week 4, the arterial lumen of the TAO rabbit was filled with relatively-organized VSMC and endothelial cell clusters with less inflammatory cells. Neorevascularization was found in the MTX-treated group. CONCLUSION: The novel TAO rabbit model shows a closer resemblance to human TAO clinically, radiographically, and histopathologically. Histological analysis of the IT progression in the TAO model suggests that it is of VSMC origin.
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Spectroscopic characterization of carbon monoxide activation by neutral metal carbides is of essential importance for understanding the structure-reactivity relationships of catalytic sites, but has been proven to be very challenging owing to the difficulty in size selection. Here, we report a size-specific infrared-vacuum ultraviolet spectroscopic study of the reactions between carbon monoxide with neutral chromium carbides. Quantum chemical calculations were carried out to identify the low-lying structures and to interpret the experimental features. The results reveal that the most stable structure of CrC3(CO)2 consists of a CCO ketenylidene unit and that of CrC4(CO)2 has a semi-bridging CO with a very low CO stretching vibrational frequency at 1821 cm-1. The electron structure analyses show that this semi-bridging CO is highly activated through the delocalized Cr-C-C three-center two-electron (3c-2e) interaction between the antibonding orbitals of CO and the metal carbide skeleton. The formation of these metal carbide carbonyls is found to be both thermodynamically exothermic and kinetically facile in the gas phase. The present findings have important implications for the mechanical understanding of the catalytic processes with isolated metal atoms/clusters dispersed on supports.
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Spectroscopic characterization of highly excited neutral transition-metal complexes is important for understanding the multifaceted reaction mechanisms between metals and ligands. In this work, the reactions of neutral chromium atoms with carbon monoxide were probed by size-specific infrared spectroscopy. Interestingly, Cr(CO)3 was found to have an unprecedented 7A2â³ septet excited state rather than the singlet ground state. A combination of experiment and theory shows that the gas-phase formation of this highly excited Cr(CO)3 is facile both thermodynamically and kinetically. Electronic structure and bonding analyses indicate that the valence electrons of Cr atoms in the septet Cr(CO)3 are in a relatively stable configuration, which facilitate the highly excited structure and the planar geometric shape (D3h symmetry). The observed septet Cr(CO)3 affords a paradigm for exploring the structure, properties, and formation mechanism of a large variety of excited neutral compounds.
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Two new dimeric Lycopodium alkaloids, casuattimines A and B (1 and 2), along with twelve previously undescribed Lycopodium alkaloids, casuattimines C-N (3-14), and eight known Lycopodium alkaloids, were isolated from Lycopodiastrum casuarinoides. Casuattimines A and B (1 and 2) are the first two ether-linked Lycopodium alkaloid dimers. Casuattimines C and D (3 and 4) are unique Lycopodium alkaloids characterized by a long fatty acid chain. Structural elucidation was achieved through HRESIMS, NMR, and electronic circular dichroism (ECD) calculations. In addition, the absolute configurations of compounds 7, 13, and 14 were determined by single crystal X-ray diffraction. Compounds 1, 2, and 4 demonstrated notable Cav3.1 channel inhibitory activities presenting IC50 values of 10.75 ± 1.02 µM, 9.33 ± 0.79 µM, and 7.14 ± 0.86 µM, respectively. The dynamics of compound 4 against the Cav3.1 channel and preliminary structure-activity relationships of these active Lycopodium alkaloids were also discussed.
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Alcaloides , Lycopodiaceae , Lycopodium , Lycopodium/química , Estrutura Molecular , Inibidores da Colinesterase/farmacologia , Lycopodiaceae/química , Alcaloides/farmacologia , Alcaloides/químicaRESUMO
BACKGROUND: Carcinoembryonic antigen (CEA) is one of the commonly used preoperative biomarkers for colorectal cancer (CRC), but no meta-analysis has evaluated the findings of all recently published studies to determine whether its postoperative level can serve as a prognostic indicator. METHODS: We conducted a systematic search for eligible literature from the PubMed, EMBASE, and Web of Science databases in October 2023. Studies that investigated the relationship between postoperative serum CEA levels and prognosis in CRC patients were included. Outcome indicators, including overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS)/recurrence-free survival (RFS), were analyzed using a fixed-effects or random-effects model. The pooled hazard ratios (HR) with 95% confidence intervals (CI) were used as effective values. RESULTS: This meta-analysis included 20 eligible studies involving 10,114 CRC patients from the East Asian and Western countries. A comprehensive analysis revealed that elevated postoperative CEA levels were associated with low OS (HR: 2.92, 95% CI: 2.36-3.62, and p < 0.000), DFS (HR: 2.81, 95% CI: 2.01-3.94, and p < 0.000), and RFS/PFS (HR: 2.52, 95% CI: 1.75-3.62, p < 0.000). A subgroup analysis by region, analysis type, distant metastasis, HR obtain method, sample size, postoperative measurement date, and study design demonstrated that the negative correlation observed between high serum CEA levels after surgery and poor prognosis was not significantly different between the subgroups. CONCLUSION: When CEA levels are found to be elevated during postoperative follow-up, more active intervention measures should be implemented to further improve the patient's survival outcomes.
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Antígeno Carcinoembrionário , Neoplasias Colorretais , Antígeno Carcinoembrionário/sangue , Humanos , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/sangue , Neoplasias Colorretais/mortalidade , Prognóstico , Biomarcadores Tumorais/sangue , Período Pós-OperatórioRESUMO
Sequence compositions of nucleic acids and proteins have significant impact on gene expression, RNA stability, translation efficiency, RNA/protein structure and molecular function, and are associated with genome evolution and adaptation across all kingdoms of life. Therefore, a devoted resource of sequence compositions and associated features is fundamentally crucial for a wide range of biological research. Here, we present CompoDynamics (https://ngdc.cncb.ac.cn/compodynamics/), a comprehensive database of sequence compositions of coding sequences (CDSs) and genomes for all kinds of species. Taking advantage of the exponential growth of RefSeq data, CompoDynamics presents a wealth of sequence compositions (nucleotide content, codon usage, amino acid usage) and derived features (coding potential, physicochemical property and phase separation) for 118 689 747 high-quality CDSs and 34 562 genomes across 24 995 species. Additionally, interactive analytical tools are provided to enable comparative analyses of sequence compositions and molecular features across different species and gene groups. Collectively, CompoDynamics bears the great potential to better understand the underlying roles of sequence composition dynamics across genes and genomes, providing a fundamental resource in support of a broad spectrum of biological studies.