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The structure of dislocation cores, the fundamental knowledge on crystal plasticity, remains largely unexplored in covalent crystals. Here, we conducted atomically resolved characterizations of dislocation core structures in a plastically deformed diamond anvil cell tip that was unloaded from an exceptionally high pressure of 360 GPa. Our observations unveiled a series of nonequilibrium dislocation cores that deviate from the commonly accepted "five-seven-membered ring" dislocation core model found in FCC-structured covalent crystals. The nonequilibrium dislocation cores were generated through a process known as "mechanical quenching," analogous to the quenching process where a high-energy state is rapidly frozen. The density functional theory-based molecular dynamic simulations reveal that the phenomenon of mechanical quenching in diamond arises from the challenging relaxation of the nonequilibrium configuration, necessitating a large critical strain of 25% that is difficult to maintain. Further electronic-scale analysis suggested that such large critical strain is spent on the excitation of valance electrons for bond breaking and rebonding during relaxation. These findings establish a foundation for the plasticity theory of covalent materials and provide insights into the design of electrical and luminescent properties in diamond, which are intimately linked to the dislocation core structure.
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Parasitic roundworms (nematodes) have lost genes involved in the de novo biosynthesis of haem, but have evolved the capacity to acquire and utilise exogenous haem from host animals. However, very little is known about the processes or mechanisms underlying haem acquisition and utilisation in parasites. Here, we reveal that HRG-1 is a conserved and unique haem transporter in a broad range of parasitic nematodes of socioeconomic importance, which enables haem uptake via intestinal cells, facilitates cellular haem utilisation through the endo-lysosomal system, and exhibits a conspicuous distribution at the basal laminae covering the alimentary tract, muscles and gonads. The broader tissue expression pattern of HRG-1 in Haemonchus contortus (barber's pole worm) compared with its orthologues in the free-living nematode Caenorhabditis elegans indicates critical involvement of this unique haem transporter in haem homeostasis in tissues and organs of the parasitic nematode. RNAi-mediated gene knockdown of hrg-1 resulted in sick and lethal phenotypes of infective larvae of H. contortus, which could only be rescued by supplementation of exogenous haem in the early developmental stage. Notably, the RNAi-treated infective larvae could not establish infection or survive in the mammalian host, suggesting an indispensable role of this haem transporter in the survival of this parasite. This study provides new insights into the haem biology of a parasitic nematode, demonstrates that haem acquisition by HRG-1 is essential for H. contortus survival and infection, and suggests that HRG-1 could be an intervention target candidate in a range of parasitic nematodes.
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Proteínas de Caenorhabditis elegans , Haemonchus , Nematoides , Parasitos , Animais , Nematoides/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Haemonchus/genética , Haemonchus/metabolismo , Heme/metabolismo , Parasitos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , MamíferosRESUMO
Intercropping is a widely recognised technique that contributes to agricultural sustainability. While intercropping leguminous green manure offers advantages for soil health and tea plants growth, the impact on the accumulation of theanine and soil nitrogen cycle are largely unknown. The levels of theanine, epigallocatechin gallate and soluble sugar in tea leaves increased by 52.87% and 40.98%, 22.80% and 6.17%, 22.22% and 29.04% in intercropping with soybean-Chinese milk vetch rotation and soybean alone, respectively. Additionally, intercropping significantly increased soil amino acidnitrogen content, enhanced extracellular enzyme activities, particularly ß-glucosidase and N-acetyl-glucosaminidase, as well as soil multifunctionality. Metagenomics analysis revealed that intercropping positively influenced the relative abundances of several potentially beneficial microorganisms, including Burkholderia, Mycolicibacterium and Paraburkholderia. Intercropping resulted in lower expression levels of nitrification genes, reducing soil mineral nitrogen loss and N2 O emissions. The expression of nrfA/H significantly increased in intercropping with soybean-Chinese milk vetch rotation. Structural equation model analysis demonstrated that the accumulation of theanine in tea leaves was directly influenced by the number of intercropping leguminous green manure species, soil ammonium nitrogen and amino acid nitrogen. In summary, the intercropping strategy, particularly intercropping with soybean-Chinese milk vetch rotation, could be a novel way for theanine accumulation.
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Camellia sinensis , Fabaceae , Glutamatos , Fabaceae/metabolismo , Esterco , Leguminas , Solo/química , Camellia sinensis/metabolismo , Glycine max , Chá , Nitrogênio/metabolismoRESUMO
Ischemic stroke is a major cause of disability and death worldwide, and its management requires urgent attention. Previous studies have shown that vagus nerve stimulation (VNS) exerts neuroprotection in ischemic stroke by inhibiting neuroinflammation and apoptosis. In this study, we evaluated the timing for VNS intervention in ischemic stroke, and the underlying mechanisms of VNS-induced neuroprotection. Mice were subjected to transient middle cerebral artery occlusion (tMCAO) for 60 min. The left vagus nerve at cervical level was exposed and attached to an electrode connected to a low-frequency electrical stimulator. Vagus nerve stimulation (VNS) was given for 60 min before, during and after tMCAO (Pre-VNS, Dur-VNS, Post-VNS). Neurological function was assessed 24 h after reperfusion. We found that all the three VNS significantly protected against the tMCAO-induced injury evidenced by improved neurological function and reduced infarct volume. Moreover, the Pre-VNS was the most effective against the ischemic injury. We found that tMCAO activated microglia in the ischemic core and penumbra regions of the brain, followed by the NLRP3 inflammasome activation-induced neuroinflammation, which finally triggered neuronal death. VNS treatment preserved α7nAChR expression in the penumbra regions, inhibited NLRP3 inflammasome activation and ensuing neuroinflammation, rescuing cerebral neurons. The role of α7nAChR in microglial NLRP3 inflammasome activation in ischemic stroke was further validated using genetic manipulations, including Chrna7 knockout mice and microglial Chrna7 overexpression mice, as well as pharmacological interventions using the α7nAChR inhibitor methyllycaconitine and agonist PNU-282987. Collectively, this study demonstrates the potential of VNS as a safe and effective strategy to treat ischemic stroke, and presents a new approach targeting microglial NLRP3 inflammasome, which might be therapeutic for other inflammation-related diseases.
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Infarto da Artéria Cerebral Média , Inflamassomos , AVC Isquêmico , Camundongos Endogâmicos C57BL , Microglia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Estimulação do Nervo Vago , Receptor Nicotínico de Acetilcolina alfa7 , Animais , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estimulação do Nervo Vago/métodos , AVC Isquêmico/metabolismo , Microglia/metabolismo , Camundongos , Inflamassomos/metabolismo , Masculino , Infarto da Artéria Cerebral Média/terapia , Neuroproteção , Camundongos KnockoutRESUMO
After the second industrial revolution, social productivity developed rapidly, and the use of fossil fuels such as coal, oil, and natural gas increased greatly in industrial production. The burning of these fossil fuels releases large amounts of greenhouse gases such as CO2, which has caused greenhouse effects and global warming. This has endangered the planet's ecological balance and brought many species, including animals and plants, to the brink of extinction. Thus, it is crucial to address this problem urgently. One potential solution is the use of syngas fermentation with microbial cell factories. This process can produce chemicals beneficial to humans, such as ethanol as a fuel while consuming large quantities of harmful gases, CO and CO2. However, syngas-fermenting microorganisms often face a metabolic energy deficit, resulting in slow cell growth, metabolic disorders, and low product yields. This problem limits the large-scale industrial application of engineered microorganisms. Therefore, it is imperative to address the energy barriers of these microorganisms. This paper provides an overview of the current research progress in addressing energy barriers in bacteria, including the efficient capture of external energy and the regulation of internal energy metabolic flow. Capturing external energy involves summarizing studies on overexpressing natural photosystems and constructing semiartificial photosynthesis systems using photocatalysts. The regulation of internal energy metabolic flows involves two parts: regulating enzymes and metabolic pathways. Finally, the article discusses current challenges and future perspectives, with a focus on achieving both sustainability and profitability in an economical and energy-efficient manner. These advancements can provide a necessary force for the large-scale industrial application of syngas fermentation microbial cell factories.
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Fermentação , Bactérias/metabolismo , Metabolismo Energético , BiocombustíveisRESUMO
Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Studies have indicated that immune dysfunction plays a central role in the pathogenesis of sepsis. Dendritic cells (DCs) play a crucial role in the emergence of immune dysfunction in sepsis. The major manifestations of DCs in the septic state are abnormal functions and depletion in numbers, which are linked to higher mortality and vulnerability to secondary infections in sepsis. Apoptosis is the most widely studied pathway of number reduction in DCs. In the past few years, there has been a surge in studies focusing on regulated cell death (RCD). This emerging field encompasses various forms of cell death, such as necroptosis, pyroptosis, ferroptosis, and autophagy-dependent cell death (ADCD). Regulation of DC's RCD can serve as a possible therapeutic focus for the treatment of sepsis. Throughout time, numerous tactics have been devised and effectively implemented to improve abnormal immune response during sepsis progression, including modifying the functions of DCs and inhibiting DC cell death. In this review, we provide an overview of the functional impairment and RCD of DCs in septic states. Also, we highlight recent advances in targeting DCs to regulate host immune response following septic challenge.
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Células Dendríticas , Sepse , Células Dendríticas/imunologia , Sepse/imunologia , Sepse/patologia , Humanos , Animais , Morte Celular Regulada , Autofagia , Apoptose , PiroptoseRESUMO
INTRODUCTION: Abnormalities in splicing factors, such as mutations or deregulated expression, can lead to aberrant splicing of target genes, potentially contributing to the pathogenesis of acute myeloid leukemia (AML). Despite this, the precise mechanism underlying the abnormal alternative splicing (AS) induced by SRSF1, a splicing factor associated with poor AML prognosis, remains elusive. METHODS: Using strict splicing criteria, we globally screened for AS events in NPMc-positive and NPMc-negative AML samples from TCGA. An AS network associated with AML prognosis was then established. Functional assays, including CCK-8, flow cytometry, and Western blot, were conducted on K562 and THP-1 cells overexpressing SRSF1. Cell viability following 72-h Omipalisib treatment was also assessed. To explore the mechanism of SRSF1-induced AS, we created a BCL2L11 miniGene with a site-specific mutation at its branch point. The AS patterns of both wild-type and mutant miniGenes were analyzed following SRSF1 overexpression in HEK-293T, along with the subcellular localization of different spliceosomes. RESULTS: SRSF1 was significantly associated with AML prognosis. Notably, its expression was markedly upregulated in refractory AML patients compared to those with a favorable chemotherapy response. Overexpression of SRSF1 promoted THP-1 cell proliferation, suppressed apoptosis, and reduced sensitivity to Omipalisib. Mechanistically, SRSF1 recognized an aberrant branch point within the BCL2L11 intron, promoting the inclusion of a cryptic exon 3, which in turn led to apoptosis arrest. CONCLUSION: Overexpression of SRSF1 and the resulting abnormal splicing of BCL2L11 are associated with drug resistance and poor prognosis in AML.
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OBJECTIVES: This study investigated the codigestion of corn straw (CS) with cow manure (CM), cow digestion solution (CD), and a strain consortium (SC) for enhanced volatile fatty acid (VFA) production. The aims of this study were to develop a sustainable technique to increase VFA yields, examine how combining microbial reagents with CS affects VFA production by functional microorganisms, and assess the feasibility of improving microbial diversity through codigestion. METHODS: Batch experiments evaluated VFA production dynamics and microbial community changes with different combinations of CS substrates with CM, CD, and SC. Analytical methods included measuring VFAs by GC, ammonia and COD by standard methods and microbial community analysis by 16S rRNA gene sequencing. RESULTS: Codigesting CS with the microbial consortium yielded initial volatile fatty acid (VFA) concentrations ranging from 0.6-1.0 g/L, which were greater than those of the other combinations (0.05-0.3 g/L). Including CM and CD further increased VFA production to 1.0-2.0 g/L, with the highest value of 2.0 g/L occurring when all four substrates were codigested. Significant ammonium reduction (194-241 mg/L to 29-37 mg/L) and COD reduction (3310-5250 mg/L to 730-1210 mg/L) were observed. Codigestion with CM and CD had greater Shannon diversity indices (3.19-3.24) than did codigestion with the other consortia (2.26). Firmicutes dominated (96.5-99.6%), with Clostridiales playing key roles in organic matter breakdown. CONCLUSIONS: This study demonstrated the feasibility of improving VFA yields and harnessing microbial diversity through anaerobic codigestion of lignocellulosic and animal waste streams. Codigestion substantially enhanced VFA production, which was dominated by butyrate, reduced ammonium and COD, and enriched fiber-degrading and fermentative bacteria. These findings can help optimize codigestion for sustainable waste management and high-value chemical production.
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Our previous study showed that COPPER-CONTAINING AMINE OXIDASE (CuAO) and AMINOALDEHYDE DEHYDROGENASE (AMADH) could regulate the accumulation of γ-aminobutyric acid (GABA) in tea through the polyamine degradation pathway. However, their biological function in drought tolerance has not been determined. In this study, Camellia sinensis (Cs) CsCuAO1 associated with CsAMADH1 conferred drought tolerance, which modulated GABA levels in tea plants. The results showed that exogenous GABA spraying effectively alleviated the drought-induced physical damage. Arabidopsis lines overexpressing CsCuAO1 and CsAMADH1 exhibited enhanced resistance to drought, which promoted the synthesis of GABA and putrescine by stimulating reactive oxygen species' scavenging capacity and stomatal movement. However, the suppression of CsCuAO1 or CsAMADH1 in tea plants resulted in increased sensitivity to drought treatment. Moreover, co-overexpressing plants increased GABA accumulation both in an Agrobacterium-mediated Nicotiana benthamiana transient assay and transgenic Arabidopsis plants. In addition, a GABA transporter gene, CsGAT1, was identified, whose expression was strongly correlated with GABA accumulation levels in different tissues under drought stress. Taken together, CsCuAO1 and CsAMADH1 were involved in the response to drought stress through a dynamic GABA-putrescine balance. Our data will contribute to the characterization of GABA's biological functions in response to environmental stresses in plants.
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Arabidopsis , Camellia sinensis , Resistência à Seca , Arabidopsis/genética , Camellia sinensis/genética , Putrescina , Plantas Geneticamente Modificadas/genética , Ácido gama-Aminobutírico , CháRESUMO
The organization of modifiable and functional building components into various superstructures is of great interest due to their broad applications. Supramolecular self-assembly, based on rationally designed building blocks and appropriately utilized driving forces, is a promising and widely used strategy for constructing superstructures with well-defined nanostructures and diverse morphologies across multiple length scales. In this study, two homogeneous organohydrogels with distinct appearances were constructed by simply mixing polyoxometalate (phosphomolybdic acid, HPMo) and a double-tailed zwitterionic quaternary ammonium amphiphile in a binary solvent of water and dimethyl sulfoxide (DMSO). The delicate balance between electrostatic attraction and repulsion of anionic HPMo clusters and zwitterionic structures drove them to co-assemble into homogeneous organohydrogels with diverse microstructures. Notably, the morphologies of the organohydrogels, including unilamellar vesicles, onion-like vesicles, and spherical aggregates, can be controlled by adjusting the ionic interactions between the zwitterionic amphiphiles and phosphomolybdic acid clusters. Furthermore, we observed an organohydrogel fabricated with densely stacked onion-like structures (multilamellar vesicles) consisting of more than a dozen layers at certain proportions. Additionally, the relationships between the self-assembled architectures and the intermolecular interactions among the polyoxometalate, zwitterionic amphiphile, and solvent molecules were elucidated. This study offers valuable insights into the mechanisms of polyoxometalate-zwitterionic amphiphile co-assembly, which are essential for the development of materials with specific structures and emerging functionalities.
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Based on the processing and compatibility, this study explored the effects of components in Corni Fructus(CF) and Astragali Radix(AR) on plasma metabolomics in diabetic nephropathy rats. SD rats were randomly divided into four groups and diabetic nephropathy rat model was induced by high-fat diet combined with 30 mg·kg~(-1) streptozotocin(STZ). Histopathological observations of kidney tissue sections of rats in each group were conducted using HE, PAS, and Masson staining. Ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry(UHPLC-Q-TOF-MS/MS) metabolomics method was employed to investigate the effects of CF before and after wine-processing combined with AR-related components on plasma metabolites in diabetic nephropathy rats. After drug treatment, kidney tissue damage and interstitial collagen fiber deposition area in diabetic nephropathy rats were improved to varying degrees(P<0.001). The detection results of plasma metabolomics showed that 71 biomarkers related to the pathogenesis of diabetic nephropathy were identified in diseased rats, mainly involving linoleic acid metabolism, caffeine metabolism, glycerophospholipid metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, arachidonic acid metabolism, phenylalanine metabolism, retinol metabolism, and ether lipid metabolism. After drug intervention, 26 of them were significantly downregulated, with better efficacy observed in precision processed herb-pair group(P-CG_5). This study elucidated from the perspective of plasma metabolomics that P-CG_5 could improve metabolic disorders in diabetic nephropathy through pathways such as phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, and caffeine metabolism, providing theoretical support and experimental basis for the clinical application of CF and AR compatibility in traditional Chinese medicine.
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Cornus , Nefropatias Diabéticas , Medicamentos de Ervas Chinesas , Metabolômica , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Ratos , Masculino , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Cornus/química , Astragalus propinquus/química , Vinho/análise , Humanos , Rim/efeitos dos fármacos , Rim/metabolismoRESUMO
BACKGROUND: Microvascular complications are associated with an overtly increased risk of adverse outcomes in patients with diabetes including coronary microvascular injury which manifested as disruption of adherens junctions between cardiac microvascular endothelial cells (CMECs). However, particular mechanism leading to diabetic coronary microvascular hyperpermeability remains elusive. METHODS: Experimental diabetes was induced in mice with adipose tissue-specific Adipsin overexpression (AdipsinLSL/LSL-Cre) and their respective control (AdipsinLSL/LSL). In addition, cultured CMECs were subjected to high glucose/palmitic acid (HG + PA) treatment to simulate diabetes for a mechanistic approach. RESULTS: The results showed that Adipsin overexpression significantly reduced cardiac microvascular permeability, preserved coronary microvascular integrity, and increased coronary microvascular density. Adipsin overexpression also attenuated cardiac dysfunction in diabetic mice. E/A ratio, an indicator of cardiac diastolic function, was improved by Adipsin. Adipsin overexpression retarded left ventricular adverse remodeling, enhanced LVEF, and improved cardiac systolic function. Adipsin-enriched exosomes were taken up by CMECs, inhibited CMECs apoptosis, and increased CMECs proliferation under HG + PA treatment. Adipsin-enriched exosomes also accelerated wound healing, rescued cell migration defects, and promoted tube formation in response to HG + PA challenge. Furthermore, Adipsin-enriched exosomes maintained adherens junctions at endothelial cell borders and reversed endothelial hyperpermeability disrupted by HG + PA insult. Mechanistically, Adipsin blocked HG + PA-induced Src phosphorylation (Tyr416), VE-cadherin phosphorylation (Tyr685 and Tyr731), and VE-cadherin internalization, thus maintaining CMECs adherens junctions integrity. LC-MS/MS analysis and co-immunoprecipitation analysis (Co-IP) unveiled Csk as a direct downstream regulator of Adipsin. Csk knockdown increased Src phosphorylation (Tyr416) and VE-cadherin phosphorylation (Tyr685 and Tyr731), while abolishing Adipsin-induced inhibition of VE-cadherin internalization. Furthermore, Csk knockdown counteracted Adipsin-induced protective effects on endothelial hyperpermeability in vitro and endothelial barrier integrity of coronary microvessels in vivo. CONCLUSIONS: Together, these findings favor the vital role of Adipsin in the regulation of CMECs adherens junctions integrity, revealing its promises as a treatment target against diabetic coronary microvascular dysfunction. Graphical abstract depicting the mechanisms of action behind Adipsin-induced regulation of diabetic coronary microvascular dysfunction.
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Diabetes Mellitus Experimental , Cardiomiopatias Diabéticas , Camundongos , Animais , Cardiomiopatias Diabéticas/genética , Diabetes Mellitus Experimental/complicações , Células Endoteliais , Fator D do Complemento/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Células CultivadasRESUMO
Atomic layer deposition (ALD), an emerging method of thin film fabrication, has recently witnessed a surge of applications in the optoelectronics field. However, reliable processes capable of controlling film composition have yet to be developed. In this work, the effect of precursor partial pressure and steric hindrance on the surface activity was presented and analyzed in detail, which led to the development of a component tailoring process for ALD composition control in intralayer for the first time. Further, a homogeneous organic/inorganic hybrid film was successfully grown. The component unit of the hybrid film under the joint action of EG and O plasma could achieve arbitrary ratios by controlling the EG/O plasma surface reaction ratio via varied partial pressures. Film growth parameters (growth rate per cycle and mass gain per cycle) and physical properties (density, refractive index, residual stress, transmission, and surface morphology) could be modulated as desired. Moreover, the hybrid film with low residual stress was effectively used in the encapsulation of flexible organic light-emitting diodes (OLEDs). Such a component tailoring process is an important step forward in ALD technology, and allowing for in-situ control of thin film components at the atomic level in intralayer.
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We study a minimal model involving two species of particles interacting via quorum-sensing rules. Combining simulations of the microscopic model and linear stability analysis of the associated coarse-grained field theory, we identify a mechanism for dynamical pattern formation that does not rely on the standard route of intraspecies effective attractive interactions. Instead, our results reveal a highly dynamical phase of chasing bands induced only by the combined effects of self-propulsion and nonreciprocity in the interspecies couplings. Turning on self-attraction, we find that the system may phase separate into a macroscopic domain of such chaotic chasing bands coexisting with a dilute gas. We show that the chaotic dynamics of bands at the interfaces of this phase-separated phase results in anomalously slow coarsening.
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OBJECTIVE: To develop and validate a nomogram based on liver stiffness (LS) for predicting symptomatic post-hepatectomy (PHLF) in patients with hepatocellular carcinoma (HCC). METHODS: A total of 266 patients with HCC were enrolled prospectively from three tertiary referral hospitals from August 2018 to April 2021. All patients underwent preoperative laboratory examination to obtain parameters of liver function. Two-dimensional shear wave elastography (2D-SWE) was performed to measure LS. Three-dimensional virtual resection obtained the different volumes including future liver remnant (FLR). A nomogram was developed by using logistic regression and determined by receiver operating characteristic (ROC) curve analysis and calibration curve analysis, which was validated internally and externally. RESULTS: A nomogram was constructed with the following variables: FLR ratio (FLR of total liver volume), LS greater than 9.5 kPa, Child-Pugh grade, and the presence of clinically significant portal hypertension (CSPH). This nomogram enabled differentiation of symptomatic PHLF in the derivation cohort (area under curve [AUC], 0.915), internal fivefold cross-validation (mean AUC, 0.918), internal validation cohort (AUC, 0.876) and external validation cohort (AUC, 0.845). The nomogram also showed good calibration in the derivation, internal validation, and external validation cohorts (Hosmer-Lemeshow goodness-of-fit test, p = 0.641, p = 0.06, and p = 0.127, respectively). Accordingly, the safe limit of the FLR ratio was stratified using the nomogram. CONCLUSION: An elevated level of LS was associated with the occurrence of symptomatic PHLF in HCC. A preoperative nomogram integrating LS, clinical and volumetric features was useful in predicting postoperative outcomes in patients with HCC, which might help surgeons in the management of HCC resection. CLINICAL RELEVANCE STATEMENT: A serial of the safe limit of the future liver remnant was proposed by a preoperative nomogram for hepatocellular carcinoma, which might help surgeons in 'how much remnant is enough in liver resection'. KEY POINTS: ⢠An elevated liver stiffness with the best cutoff value of 9.5 kPa was associated with the occurrence of symptomatic post-hepatectomy liver failure in hepatocellular carcinoma. ⢠A nomogram based on both quality (Child-Pugh grade, liver stiffness, and portal hypertension) and quantity of future liver remnant was developed to predict symptomatic post-hepatectomy liver failure for HCC, which enabled good discrimination and calibration in both derivation and validation cohorts. ⢠The safe limit of future liver remnant volume was stratified using the proposed nomogram, which might help surgeons in the management of HCC resection.
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Carcinoma Hepatocelular , Hipertensão Portal , Falência Hepática , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Hepatectomia/efeitos adversos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Nomogramas , Estudos Prospectivos , Falência Hepática/etiologia , Falência Hepática/diagnóstico , Hipertensão Portal/complicações , Hipertensão Portal/cirurgia , Estudos RetrospectivosRESUMO
The ruthenium-catalyzed reaction of aryl methyl thioethers with vinylaziridines affords ortho-position mono- or bis-allylation products depending on substituents on the phenyl rings of sulfide substrates or the ratio of reactants. The reaction also features mild reaction conditions, good product yields, wide scope of substrates, good compatibility of functional groups, and the selective formation of E-configurated C-C double bonds.
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BACKGROUND: Posterior reversible encephalopathy syndrome (PRES) is a rare neurological disorder with complex physiopathological mechanisms that have not been fully understood. Early identification is of great prognostic significance, of which the symptoms and radiological abnormalities can be completely reversed. If the diagnosis and treatment are delayed, ischemia and massive infarction may be developed in some patients. Posterior reversible encephalopathy syndrome (PRES) has been reported mainly in association with postpartum eclampsia, which have been rarely reported, while the association with hypothyroidism has not been reported at home or abroad. CASE PRESENTATION: Here we report on a pregnant 29-year-old with multipara and a chief complication of hypothyroidism. She presented in the emergency department with frequent attacks of severe headache symptoms resulting from reversible cerebral vasoconstriction syndrome (RCVS), accompanied with prenatal eclampsia. PRES was determined by radiological examination. CONCLUSION: To the best of our knowledge, this is the first case of PRES complicated by hypothyroidism and prepartum eclampsia.Clinicians should be alert for the co-occurence of eclampsia, PRES, and RCVS when patients have convulsions after a typical throbbing headache. Moreover, regular monitoring of thyroid function during pregnancy should also occupy certain special attention.
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Eclampsia , Hipotireoidismo , Síndrome da Leucoencefalopatia Posterior , Transtornos Puerperais , Gravidez , Feminino , Humanos , Adulto , Eclampsia/diagnóstico , Síndrome da Leucoencefalopatia Posterior/complicações , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Convulsões/complicações , Transtornos Puerperais/diagnóstico , Transtornos Puerperais/etiologia , Cefaleia/complicações , Hipotireoidismo/complicaçõesRESUMO
Since cells are the basic structural and functional units of organisms, the detection or quantitation of cells is one of the most common basic problems in life science research. The established cell detection techniques mainly include fluorescent dye labeling, colorimetric assay, and lateral flow assay, all of which employ antibodies as cell recognition elements. However, the widespread application of the established methods generally dependent on antibodies is limited, because the preparation of antibodies is complicated and time-consuming, and unrecoverable denaturation is prone to occur with antibodies. By contrast, aptamers that are generally selected through the systematic evolution of ligands by exponential enrichment can avoid the disadvantages of antibodies due to their controllable synthesis, thermostability, and long shelf life, etc. Accordingly, aptamers may serve as novel molecular recognition elements like antibodies in combination with various techniques for cell detection. This paper reviews the developed aptamer-based cell detection methods, mainly including aptamer-fluorescent labeling, aptamer-isothermal amplification assay, electrochemical aptamer sensor, aptamer-based lateral flow analysis, and aptamer-colorimetric assay. The principles, advantages, progress of application in cell detection and future development trend of these methods were specially discussed. Overall, different assays are suitable for different detection purposes, and the development of more accurate, economical, efficient, and rapid aptamer-based cell detection methods is always on the road in the future. This review is expected to provide a reference for achieving efficient and accurate detection of cells as well as improving the usefulness of aptamers in the field of analytical applications.
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Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes , Ligantes , Anticorpos/química , Tecnologia , Técnicas Biossensoriais/métodosRESUMO
Harmful algal blooms (HABs) caused by Prorocentrum minimum have seriously posed economic losses and ecological disasters. To reduce these losses, aptamers are used as a new molecular probe to establish rapid methods. Herein, to improve the affinity and application of aptamers in the detection of harmful algae, the optimization was performed on the previously reported aptamers against P. minimum. First, a total of seven candidate aptamers, including three truncated aptamers (TA1, TA2 and TA3) and four mutant aptamers (MA1, MA2, MA3 and MA4), were obtained by truncation and G-quadruplex (GQ)-forming mutation. Next, the specificity and affinity test by flow cytometry revealed that except for TA1 and TA2, all of the candidate aptamers are specific with the equilibrium dissociation constant of (40.4 ± 5.5) nM for TA3, (63.3 ± 24.0) nM for MA1, (71.7 ± 14.6) nM for MA2, (365.9 ± 74.4) nM for MA3, and (21.1 ± 0.5) nM for MA4, respectively. The circular dichroism analysis of the mutant aptamers demonstrated that the GQ structures formed by MA1/MA2, MA3 and MA4 were antiparallel, mixed parallel and parallel, respectively. The affinity of aptamers with various GQ is in the order of parallel structure > antiparallel structure > mixed parallel structure. In addition, to further improve binding ability, the binding conditions of MA4 were optimized as follows: binding time, 60 min; binding temperature, 37 °C; pH of the binding buffer, 7.5; and Na+/Mg2+ concentration in the binding buffer, 100 mM/0.5 mM. The binding examination by fluorescence microscopy showed that MA4 had a stronger binding ability to P. minimum than the original aptamer. Taken together, this study not only obtained an aptamer with higher affinity than the original aptamer, which laid a good foundation for subsequent application, but also may provide a feasible reference method for aptamer optimization.
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Aptâmeros de Nucleotídeos , Quadruplex G , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Sondas MolecularesRESUMO
BACKGROUND: Ischemic stroke is a severe type of stroke with high disability and mortality rates. In recent years, microglial exosome-derived miRNAs have been shown to be promising candidates for the treatment of ischemic brain injury and exert neuroprotective effects. Mechanisms underlying miRNA dysregulation in ischemic stroke are still being explored. Here, we aimed to verify whether miRNAs derived from exosomes exert effects on functional recovery. METHODS: MiR-212-5p agomir was employed to upregulate miR-212-5p expression in a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) as well as an oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro. Western blot analysis, qRT-PCR and immunofluorescence staining and other methods were applied to explore the underlying mechanisms of action of miR-212-5p. RESULTS: The results of our study found that intervention with miR-212-5p agomir effectively decreased infarct volume and restored motor function in MCAO/R rats. Mechanistically, miR-212-5p agomir significantly reduced the expression of PlexinA2 (PLXNA2). Additionally, the results obtained in vitro were similar to those achieved in vivo. CONCLUSION: In conclusion, the present study indicated that PLXNA2 may be a target gene of miR-212-5p, and miR-212-5p has great potential as a target for the treatment and diagnosis of ischemic stroke.