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An outstanding challenge in condensed-matter-physics research over the past three decades has been to understand the pseudogap (PG) phenomenon of the high-transition-temperature (high-Tc) copper oxides. A variety of experiments have indicated a symmetry-broken state below the characteristic temperature T* (refs. 1-8). Among them, although the optical study5 indicated the mesoscopic domains to be small, all these experiments lack nanometre-scale spatial resolution, and the microscopic order parameter has so far remained elusive. Here we report, to our knowledge, the first direct observation of topological spin texture in an underdoped cuprate, YBa2Cu3O6.5, in the PG state, using Lorentz transmission electron microscopy (LTEM). The spin texture features vortex-like magnetization density in the CuO2 sheets, with a relatively large length scale of about 100 nm. We identify the phase-diagram region in which the topological spin texture exists and demonstrate the ortho-II oxygen order and suitable sample thickness to be crucial for its observation by our technique. We also discuss an intriguing interplay observed among the topological spin texture, PG state, charge order and superconductivity.
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Spinel oxides have emerged as a promising candidate in the realm of nanozymes with variable oxidation states, while their limited active sites and low conductivity hinder further application. In this work, we synthesize a series of metal-doped NiCo2O4 nanospheres decorated with Pd, which are deployed as highly efficient nanozymes for the detection of cancer biomarkers. Through meticulous modulation of the molar ratio between NiCo2O4 and Pd, we orchestrated precise control over the oxygen vacancies and electronic structure within the nanozymes, a key factor in amplifying the catalytic prowess. Leveraging the superior H2O2 reduction catalytic properties of Fe-NiCo2O4@Pd, we have successfully implemented its application in the electrochemical detection of biomarkers, achieving unparalleled analytical performance, much higher than that of Pd/C and other reported nanozymes. This research paves the way for innovative electron modification strategies in the design of high-performance nanozymes, presenting a formidable tool for clinical diagnostic analyses.
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Cobalto , Peróxido de Hidrógeno , Óxidos , Paladio , Catálisis , Paladio/química , Cobalto/química , Óxidos/química , Peróxido de Hidrógeno/química , Oxidación-Reducción , Níquel/química , Humanos , Técnicas ElectroquímicasRESUMEN
AXIN1, has been initially identified as a prominent antagonist within the WNT/ß-catenin signaling pathway, and subsequently unveiled its integral involvement across a diverse spectrum of signaling cascades. These encompass the WNT/ß-catenin, Hippo, TGFß, AMPK, mTOR, MAPK, and antioxidant signaling pathways. The versatile engagement of AXIN1 underscores its pivotal role in the modulation of developmental biological signaling, maintenance of metabolic homeostasis, and coordination of cellular stress responses. The multifaceted functionalities of AXIN1 render it as a compelling candidate for targeted intervention in the realms of degenerative pathologies, systemic metabolic disorders, cancer therapeutics, and anti-aging strategies. This review provides an intricate exploration of the mechanisms governing mammalian AXIN1 gene expression and protein turnover since its initial discovery, while also elucidating its significance in the regulation of signaling pathways, tissue development, and carcinogenesis. Furthermore, we have introduced the innovative concept of the AXIN1-Associated Phosphokinase Complex (AAPC), where the scaffold protein AXIN1 assumes a pivotal role in orchestrating site-specific phosphorylation modifications through interactions with various phosphokinases and their respective substrates.
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Vía de Señalización Wnt , beta Catenina , Animales , Ontología de Genes , Proteína Axina/genética , Proteína Axina/metabolismo , Vía de Señalización Wnt/genética , Fosforilación , Proteolisis , beta Catenina/metabolismo , Mamíferos/metabolismoRESUMEN
Hybridization between invasive pest species may lead to significant genetic and economic impacts that require close monitoring. The two most invasive and destructive termite species worldwide, Coptotermes formosanus Shiraki and Coptotermes gestroi (Wasmann), have the potential for hybridization in the field. A three-year field survey conducted during the dispersal flight season of Coptotermes in Taiwan identified alates with atypical morphology, which were confirmed as hybrids of the two Coptotermes species using microsatellite and mitochondrial analyses. Out of 27,601 alates collected over three years, 4.4% were confirmed as hybrid alates, and some advanced hybrids (>F1 generations) were identified. The hybrid alates had a dispersal flight season that overlapped with the two parental species 13 out of 15 times. Most of the hybrid alates were females, implying that mating opportunities beyond F1 may primarily be possible through female hybrids. However, the incipient colony growth results from all potential mating combinations suggest that only backcross colonies with hybrid males could sometimes lead to brood development. The observed asymmetrical viability and fertility of hybrid alates may critically reduce the probability of advanced-hybrid colonies being established in the field.
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Flujo Génico , Hibridación Genética , Isópteros , Repeticiones de Microsatélite , Animales , Isópteros/genética , Isópteros/fisiología , Femenino , Masculino , Repeticiones de Microsatélite/genética , Taiwán , Especies Introducidas , ADN Mitocondrial/genéticaRESUMEN
Ultrafast excited-state dynamics of the simplest nitrostilbenes, namely trans-4-nitrostilbene (t-NSB), was studied in solvents of various polarities with ultrafast broadband time-resolved fluorescence and transient absorption spectroscopies, and by quantum-chemical computations. The results revealed that the initially excited S1(ππ*) state deactivation dynamics is strongly influenced by the solvent polarity. Specifically, the t-NSB S1-state lifetime decreases by three orders of magnitude from â¼60 ps in high-polarity solvents to â¼60 fs in nonpolar solvents. The strong solvent-polarity dependence arises from the differences in dipole moments among the S1 and relevant states, including the major intersystem crossing (ISC) receiver triplet states, and therefore, the solvent polarity can modulate their relative energies and ISC rates. In nonpolar solvents, the sub-100 fs lifetime is due to a combination of efficient ISC and internal conversion. In medium-polarity solvents, the S1-state population decays via a competing ISC relaxation mechanism in a biphasic manner, and the ISC rates are found to obey the inverse energy gap law of the strong coupling case. In high-polarity solvents, the S1 state is stabilized to a much lower energy such that ISC becomes energetically infeasible, and the S1 state decays via barrier crossing along the torsion angle of the central ethylenic bond to the nonfluorescent perpendicular configuration. Regardless of the initial S1-state deactivation pathways in various solvents, the excited-state population is ultimately trapped in the metastable T1-state perpendicular configuration, at which a slower ISC occurs to bring the system to the ground state and bifurcate into either trans or cis form of NSB.
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Bentonite is a non-metallic mineral with montmorillonite as the main component. It is an environmentally friendly mineral material with large reserves, wide distribution, and low price. Bentonite can be easily modified organically using the surfactant saponin to obtain saponin-modified bentonite (Sap-BT). This study investigates the immobilization of crude enzymes obtained from Trametes versicolor by physical adsorption with Sap-BT. Thus, saponin-modified bentonite immobilized crude enzymes (CE-Sap-BT) were developed to remove benzo[a]pyrene. Immobilization improves the stability of free enzymes. CE-Sap-BT can maintain more than 80% of activity at 45 °C and after storage for 15 d. Additionally, CE-Sap-BT exhibited a high removal rate of benzo[a]pyrene in soil, with 65.69% after 7 d in highly contaminated allotment soil and 52.90% after 6 d in actual soil contaminated with a low concentration of benzo[a]pyrene at a very low laccase dosage (0.1 U/3 g soil). The high catalytic and removal performance of CE-Sap-BT in contaminated sites showed more excellent practical application value.
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Bioremediation of PAHs-contaminated soil by immobilized enzymes is a promising technology. Nevertheless, the practical implementation of highly efficient enzymatic remediation remains confined to laboratory settings, with limited experience in full-scale applications. In this study, the extracellular enzymes from white rot fungi are fully applied to treat sites contaminated with PAHs by combining a new hydrogel microenvironment and a biopiling system. The full-scale project was conducted on silty loam soil contaminated with PAHs. In line with China's guidelines for construction land, 7 out of the 12 PAHs identified are considered to be a threat to the soil quality of construction sites, with benzo[a]pyrene levels reaching 1.50 mg kg-1, surpassing the acceptable limit of 0.55 mg kg-1 for the first type of land. After 7 days of remediation, the benzo[a]pyrene level decreased from 1.50 mg kg-1 to 0.51 mg kg-1, reaching the remediation standard of Class I screening values, with a removal rate of 66%. Microbiomes were utilized to assess the microbial biodiversity and structure analyses for PAHs biodegradation. The remediation enhanced the abundance of dominant bacterium (Marinobacter, Pseudomonas, and Truepera) and fugin (Thielavia, Neocosmospora, and Scedosporium). The research offers further insights into the exploration of soil remediation on the full-scale of the immobilized enzyme and biopiling technology.
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Objective: Gastric cancer with peritoneal metastasis is considered to be final stage gastric cancer. One current treatment approach for this condition is combined cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC). However, the therapeutic mechanisms of HIPEC remain largely undescribed. Method: In order to assess the cellular effects of HIPEC in vitro, we treated AGS human gastric adenocarcinoma cells with or without 5-fluorouracil (5-Fu) at 37 °C or at 43 °C (hyperthermic temperature) for 1 h followed by incubation at 37 °C for 23 h. The impacts of hyperthermia/5-Fu on apoptosis, cell survival signals, oxidative stress, chemoresistance-related proteins and programmed death-ligand 1 (PD-L1) expression were measured. Results: Our results showed that hyperthermia potentiates 5-Fu-mediated cytotoxicity in AGS cells. Furthermore, the combination of 5-Fu and hyperthermia reduces levels of both phosphorylated STAT3 and STAT3, while increasing the levels of phosphorylated Akt and ERK. In addition, 5-Fu/hyperthermia enhances reactive oxygen species and suppresses superoxide dismutase 1. Chemoresistance-related proteins, such as multidrug resistance 1 and thymidylate synthase, are also suppressed by 5-Fu/hyperthermia. Interestingly, hyperthermia enhances 5-Fu-mediated induction of glycosylated PD-L1, but 5-Fu-mediated upregulation of PD-L1 surface expression is prevented by hyperthermia. Conclusion: Taken together, our findings provide insights that may aid in the development of novel therapeutic strategies and enhanced therapeutic efficacy of HIPEC.
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Hipertermia Inducida , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Antígeno B7-H1/uso terapéutico , Resistencia a Antineoplásicos , Hipertermia Inducida/métodos , Fluorouracilo/farmacología , Fluorouracilo/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia CombinadaRESUMEN
INTRODUCTION: Early identification of patients with sepsis at high risk of death remains a challenge, and whether brain natriuretic peptide (BNP) or N-terminal pro-B-type natriuretic peptide (NT-proBNP) has a prognostic effect on patients with sepsis is controversial. Here, we clarified the prognostic value of BNP and NT-proBNP and sought to establish suitable cutoff values and intervals. METHODS: We searched five databases to identify studies that met the inclusion criteria. The primary outcomes were the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under the curve (AUC), and corresponding 95% credible interval (95% CI) of BNP and NT-proBNP. The secondary outcomes were the sensitivity and specificity of BNP or NT-proBNP in subgroup analyses. RESULTS: Forty-seven studies were included in our meta-analysis. The pooled sensitivity of NT-proBNP (0.77 [0.68, 0.84]) was weaker than that of BNP (0.82 [0.76, 0.87]), the pooled specificity of NT-proBNP (0.70 [0.60, 0.77]) was less than that of BNP (0.77 [0.71, 0.82]), and the AUC of BNP (0.87 [0.83-0.89]) was greater than that of NT-proBNP (0.80 (0.76-0.83]). The results of the subgroup analysis showed that the cutoff range of 400-800 pg/mL for BNP had high sensitivity (0.86 [0.74-0.98]) and specificity (0.87 [0.81-0.93]) and was probably the most appropriate cutoff range. CONCLUSIONS: Elevated levels of BNP and NT-proBNP were significantly related to the mortality of patients with sepsis and had a moderate prognostic value in predicting the mortality of patients with sepsis. In addition, our meta-analysis preliminarily established appropriate cutoff values for BNP and NT-proBNP.
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Biomarcadores , Péptido Natriurético Encefálico , Fragmentos de Péptidos , Sepsis , Humanos , Péptido Natriurético Encefálico/sangre , Sepsis/mortalidad , Sepsis/sangre , Sepsis/diagnóstico , Biomarcadores/sangre , Fragmentos de Péptidos/sangre , Pronóstico , Valor Predictivo de las Pruebas , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: To investigate serum irisin levels in girls at different developmental status and explore the significance of irisin for the diagnosis of central precocious puberty (CPP) in girls. METHODS: In this cross-sectional study 111 girls were enrolled, including 43 cases of CPP, 44 cases of peripheral precocious puberty (PPP) and 24 cases of girls with normal sexual development as controls. The data on age, weight and height, measured blood levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), estradiol, and irisin were collected. Pelvic Doppler ultrasound was performed to evaluate uterine length, transverse diameter, anteroposterior diameter. The girls were divided into non-CPP group and CPP group according to gonadotropin-releasing hormone (GnRH) stimulation test. RESULTS: Serum irisin levels were significantly higher in CPP group than in PPP group and normal control group. Serum irisin level was positively correlated with basal LH level, basal FSH level, peak LH level, peak LH /FSH ratio, uterine volume, bone age, and bone age index. The area under the curve, cut-off value, sensitivity and specificity of serum irisin were 0.958, 219.255 pg/ml, 100% and 80.6%. The combined diagnosis of CPP in girls by serum irisin and serum basal LH combined with uterine volume had an AUC, sensitivity, and specificity of 0.994, 97.6%, and 100%, superior to that of the single index. CONCLUSIONS: Serum irisin level in girls with CPP is significantly increased. An irisin combined index could help the diagnosis of CPP in girls.
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Fibronectinas , Hormona Folículo Estimulante , Hormona Luteinizante , Pubertad Precoz , Humanos , Pubertad Precoz/sangre , Pubertad Precoz/diagnóstico , Femenino , Estudios Transversales , Fibronectinas/sangre , Niño , Hormona Luteinizante/sangre , Hormona Folículo Estimulante/sangre , Estudios de Casos y Controles , Biomarcadores/sangre , Sensibilidad y Especificidad , Estradiol/sangre , Útero/diagnóstico por imagenRESUMEN
Recently, posture recognition technology has advanced rapidly. Herein, we present a novel posture angle calculation system utilizing a single inertial measurement unit and a spatial geometric equation to accurately identify the three-dimensional (3D) motion angles and postures of both the upper and lower limbs of the human body. This wearable system facilitates continuous monitoring of body movements without the spatial limitations or occlusion issues associated with camera-based methods. This posture-recognition system has many benefits. Providing precise posture change information helps users assess the accuracy of their movements, prevent sports injuries, and enhance sports performance. This system employs a single inertial sensor, coupled with a filtering mechanism, to calculate the sensor's trajectory and coordinates in 3D space. Subsequently, the spatial geometry equation devised herein accurately computed the joint angles for changing body postures. To validate its effectiveness, the joint angles estimated from the proposed system were compared with those from dual inertial sensors and image recognition technology. The joint angle discrepancies for this system were within 10° and 5° when compared with dual inertial sensors and image recognition technology, respectively. Such reliability and accuracy of the proposed angle estimation system make it a valuable reference for assessing joint angles.
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Postura , Humanos , Postura/fisiología , Dispositivos Electrónicos Vestibles , Fenómenos Biomecánicos/fisiología , Movimiento/fisiología , Masculino , Algoritmos , Extremidades/fisiologíaRESUMEN
Although the unique properties of nanomaterials have endowed enzyme-mimic catalysts with broad applications, the development of catalysts still relies on trial-and-error strategies without predictive indicators. Surface electronic structures have rarely been studied in enzyme-mimic catalysts. Herein, we present a platform for understanding the impact of surface electronic structures on electrocatalysis toward H2O2 decomposition, using the Pd icosahedra (Pd ico), Pd octahedra (Pd oct) and Pd cubic nanocrystals as electrocatalysts. The electronic properties on Pd were modulated with a correlation of surface orientation. We revealed the relationship between the electronic properties and electrocatalytic performance, in which the surface electron accumulation can boost the electrocatalytic activity of the enzyme-mimic catalysts. As a result, the Pd icodimer exhibits the highest electrocatalytic and sensing efficiency. This work offers new perspectives for the investigation of structure-activity relationships and provides an effective knob for utilizing the surface electronic structures to boost the catalytic performance for enzyme-mimics.
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INTRODUCTION: The best anesthetic choice for patients with acute posterior circulation stroke during endovascular treatment (EVT) remains uncertain. METHOD: We searched five databases to identify studies that met the inclusion criteria. Our primary outcome measure was functional independence (FI). Secondary outcomes were 3-month mortality, any intracranial hemorrhage (ICH), symptomatic ICH (sICH), successful reperfusion, and procedure- and ventilator-associated complications. RESULTS: A total of 10 studies were included in our meta-analysis. No significant differences were detected between the general anesthesia (GA) and conscious sedation and local anesthesia (CS/LA) groups in 3-month FI (nine studies; OR=0.69; 95% CI 0.45-1.06; P=0.083; I2=66%;), 3-month mortality (nine studies; OR=1.41; 95% CI 0.94-2.11; P=0.096; I2=61.2%;), any ICH (three studies; OR=0.75; 95% CI 0.44-1.25; P=0.269; I2=0%;), or sICH (six studies; OR=0.64; 95% CI 0.40-1.04; P=0.073; I2=0%;). No significant differences were observed for successful reperfusion (10 studies; OR=1.17; 95% CI 0.91-1.49; P=0.219; I2=0%;), procedure-related complications (four studies; OR=1.14; 95% CI 0.70-1.87; P=0.603; I2=7.9%;), or respiratory complications (four studies; OR=1.19; 95% CI 0.61-2.32; P=0.616; I2=64.9%;) between the two groups. CONCLUSIONS: Our study showed no differences in 3-month FI, 3-month mortality, and successful reperfusion between patients treated with GA and those treated with CS/LA. Additionally, no increased risk of hemorrhagic transformation or pulmonary infection was observed in the CS/LA group. These results indicate that CS/LA may be an EVT option for acute posterior circulation stroke patients.
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Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Isquemia Encefálica/complicaciones , Anestesia Local/efectos adversos , Accidente Cerebrovascular Isquémico/etiología , Sedación Consciente/efectos adversos , Sedación Consciente/métodos , Resultado del Tratamiento , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Anestesia General/efectos adversos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/etiología , Hemorragias Intracraneales/etiología , Trombectomía/efectos adversosRESUMEN
Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants with carcinogenic, mutagenic and teratogenic effects. The white-rot fungi in the fungal group have significant degradation ability for high molecular weight organic pollutants. However, exogenous fungi are easily antagonized by indigenous microorganisms. Low molecular weight organic acids, a small molecular organic matter secreted by plants, can provide carbon sources for soil microorganisms. Combining organic acids with white rot fungi may improve the nutritional environment of fungi. In this study, immobilized Trametes versicolor was used to degrade benzo[a]pyrene in soil, and its effect on removing benzo[a]pyrene in soil mediated by different low molecular weight organic acids was investigated. The results showed that when the degradation was 35 days, the removal effect of the experimental group with citric acid was the best, reaching 43.7%. The degradation effect of Trametes versicolor on benzo[a]pyrene was further investigated in the liquid medium when citric acid was added, and the effects of citric acid on the biomass, extracellular protein concentration and laccase activity of Trametes versicolor were investigated by controlling different concentrations of citric acid. In general, citric acid can act as a carbon source for Trametes versicolor and promote its extracellular protein secretion and laccase activity, thereby accelerating the mineralization of benzo[a]pyrene by Trametes versicolor. Therefore, citric acid can be used as a biostimulant in the remediation of PAHs contaminated soil with Trametes versicolor.
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Benzo(a)pireno , Biodegradación Ambiental , Ácido Cítrico , Contaminantes del Suelo , Benzo(a)pireno/toxicidad , Benzo(a)pireno/metabolismo , Ácido Cítrico/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad , Lacasa/metabolismo , Microbiología del Suelo , Polyporaceae/metabolismo , Trametes/metabolismo , BiomasaRESUMEN
Trichloroethylene (TCE) poses a potentially toxic threat to humans and the environment and widely exists in contaminated sites. White rot fungi effectively degrade refractory pollutants, while a few research studies use white rot fungi to degrade TCE. In this study, we investigated TCE biodegradation by white rot fungi and the potential influencing factors in the environment and attempted to research the effect of TCE on the physiological characteristics of white rot fungi. White rot fungi (Trametes versicolor, Pseudotrametes gibbosa, Pycnoporus sanguines and Pleurotus ostreatus) were added to the liquid medium for shock culture. The results revealed that T. versicolor exhibited the most pronounced efficacy in removing TCE, with a degradation rate of 81.10% within a 7 d period. TCE induces and is degraded by cytochrome P450 enzymes. High pH and Cr(VI) adversely affected the effectiveness of the biodegradation of TCE, but the salinity range of 0-1% had less effect on biodegradation. Overall, the effectiveness of degradation of TCE by T. versicolor has been demonstrated, and it provides a reference for the application prospects of white rot fungi in TCE-contaminated soils.
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Biodegradación Ambiental , Tricloroetileno , Tricloroetileno/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad , Polyporaceae/metabolismoRESUMEN
Background and Objectives: Optimal opioid analgesia is an excellent analgesia that does not present unexpected adverse effects. Nalbuphine, acting on the opioid receptor as a partial mu antagonist and kappa agonist, is considered a suitable option for patients undergoing laparoscopic surgery. Therefore, we aim to investigate the appropriate dosage of nalbuphine for post-operative pain management in patients with laparoscopic cholecystectomy. Materials and Methods: Patients were randomly categorized into low, medium, and high nalbuphine groups. In each group, a patient control device for post-operative pain control was programed with a low (0.05 mg/kg), medium (0.10 mg/kg), or high (0.20 mg/kg) nalbuphine dose as a loading dose and each bolus dose with a lockout interval of 7 min and without background infusion. Primary and secondary outcomes included the post-operative pain scale and nalbuphine consumption, and episodes of post-operative opioid-related adverse events and satisfactory scores. Results: The low-dosage group presented a higher initial self-reported pain score in comparison to the other two groups for the two hours post-op (p = 0.039) but presented lower nalbuphine consumption than the other two groups for four hours post-op (p = 0.047). There was no significant difference in the analysis of the satisfactory score and adverse events. Conclusions: An appropriate administration of nalbuphine could be 0.1 to 0.2 mg/kg at the initial four hours; this formula could be modified to a lower dosage (0.05 mg/kg) in the post-operative management of laparoscopic cholecystectomy.
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Analgesia , Colecistectomía Laparoscópica , Nalbufina , Humanos , Nalbufina/efectos adversos , Analgésicos Opioides/efectos adversos , Colecistectomía Laparoscópica/efectos adversos , Dolor Postoperatorio/tratamiento farmacológicoRESUMEN
Electrochemical DNA (E-DNA) biosensors based on interface-mediated hybridization reactions are promising for point-of-care testing (POCT). However, the low efficiency of target recycle amplification and the steric hindrance at the electrode interface limit their sensing performance. Herein, we propose a base-stacking-driven catalytic hairpin assembly (BDCHA), a nucleic acid amplification reaction strategy, for POCT. The introduction of the base-stacking effect in this strategy increases the thermodynamic stability of the product, thereby effectively improving the recycling efficiency. Also, it enables the interface-mediated hybridization to maintain stability with even fewer bases in the reaction-binding domain, hence minimizing DNA secondary structure formation or intertwining at the electrode surface and ameliorating the steric hindrance limitation. The introduced base-stacking effect makes the electrode serve as a "booster" by integrating the advantages of homogeneous and heterogeneous reactions, giving BDCHA an increased reaction rate of about 20-fold, compared to the conventional catalytic hairpin assembly. As a proof of concept, our BDCHA was applied in constructing a portable E-DNA biosensor for the detection of a SARS-CoV-2 N gene sequence fragment. A simple 30 min one-pot incubation is required, and the results can be readily read on a smartphone, making it portable and user-friendly for POCT.
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Técnicas Biosensibles , COVID-19 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , ADN/química , Hibridación de Ácido Nucleico/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Biosensibles/métodos , Electrodos , Pruebas en el Punto de Atención , Técnicas Electroquímicas/métodos , Límite de DetecciónRESUMEN
The single-atom sites (SAs) have achieved enhanced performance toward oxygen reduction reaction (ORR) with the effective utilization of the active sites. However, the excess adsorption of the intermediates and the limited stability hinders performance improvement. Metal clusters with promising stability and weak adsorption can be used as potential substitutions, but the lack of active sites is considered undesirable for catalytic reactions. Herein, a framework of Fe nanoclusters combined with SAs on One dimensional (1D) carbon nanotubes (Fe3 C-NCNTs 90 min CC-1 ) is synthesized to confirm the synergistic atom-cluster interaction. The composite exhibits strong polarization and electron redistribution between nanocluster and SAs. The electron redistribution will significantly boost the electron transport and the desorption of the intermediates, which is confirmed by off-axis holography and DFT calculation. The electrocatalytic performance is significantly enhanced as the half-wave potential of ORR increased 75 mV and the potential of OER increased 133 mV compared with the sample without nanoclusters. Furthermore, such a bifunctional catalyst endows homemade Zn-air batteries (ZABs) with high power density and long-term stability. This work paves a facile route to design bifunctional ORR/OER electrocatalysts consisting of 0D composite structures.
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Engineering phase transition in micro-nanomaterials to optimize the dielectric properties and further enhance the electromagnetic microwave absorption (EMA) performance is highly desirable. However, the severe synthesis conditions restrict the design of EMA materials featuring controllable phases, which hinders the tunability of effective absorption bandwidth (EAB) and leads to an unclear loss mechanism. Herein, a seed phase decomposition-controlled strategy is proposed to induct nickel sulfide (NiSx ) absorbers with controllable phases and hollow sphere nature. Transmission electron microscopy holography and theoretical calculations evidence that the reconstruction of atoms in phase transition induces numerous heterogeneous interfaces and lattice defects/sulfur vacancies to cause varied work functions and local electronic redistribution, which contributes to reinforced dielectric polarization. As a result, the optimized NiS2 /NiS heterostructure enables enhanced EM attenuation capability with a wide EAB of 5.04 GHz at only 1.6 mm, compared to that of NiS2 and NiS. Moreover, the correlation between EAB and NiS phase content is demonstrated as the "volcano" feature. This study on the concept of phase transition of micro-nanomaterials can offer a novel approach to constructing highly efficient absorbers for EMA and other functionalities.
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BACKGROUND: Hepatocellular carcinoma (HCC) has a high incidence and mortality rate despite various treatment options, including 125I seed implantation. However, recurrence and radiation resistance remain challenging issues. Hsa_circ_0007895 (circEYA3)-derived from exons 2-6 of EYA3-facilitates the proliferation and progression of pancreatic ductal adenocarcinoma. However, the role of circEYA3 in HCC 125I radiation resistance remains unclear. Thus, we aimed to investigate the functions and underlying molecular mechanisms of circEYA3 in HCC under 125I and X-ray irradiation conditions. METHODS: CircEYA3 was identified by RNA-seq in patients with HCC before and after 125I seed implantation treatment, followed by fluorescence in situ hybridization and RNase R assays. The radiosensitivity of HCC cell lines irradiated with 125I seeds or external irradiation were evaluated using the Cell Counting Kit 8, flow cytometry, γH2A.X immunofluorescence and comet assays. RNA pull-down and RNA immunoprecipitation assays were performed to explore the interactions between circEYA3 and IGF2BP2. DTX3L mRNA was identified by RNA-seq in PLC/PRF/5 cells with overexpressed circEYA3. The corresponding in vitro results were verified using a mouse xenograft model. RESULTS: CircEYA3 decreased the radiosensitivity of HCC cells both in vitro and in vivo. Notably, using a circRNA pulldown assay and RNA-binding protein immunoprecipitation, we identified IGF2BP2 as a novel and robust interacting protein of circEYA3. Mechanistically, circEYA3 binds to IGF2BP2 and enhances its ability to stabilize DTX3L mRNA, thereby specifically alleviating radiation-induced DNA damage in HCC cells. CONCLUSIONS: Our findings demonstrate that circEYA3 increases the radioresistance of HCC to 125I seeds and external irradiation via the IGF2BP2/DTX3L axis. Thus, circEYA3 might be a predictive indicator and intervention option for 125I brachytherapy or external radiotherapy in HCC.