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Metallic sodium is regarded as the most potential anode for sodium-ion batteries due to its high capacity and earth-abundancy. Nevertheless, uncontrolled Na dendrite growth and infinite volume change remain great challenges for developing high-performance sodium metal batteries. This work provides a simple and general approach to stabilize sodium metal anode (SMA) by constructing Sn nanoparticles-anchored laser-induced graphene on copper foil (Sn@LIG@Cu) consisting of Sn@LIG composite, polyimide (PI) columns, and Cu current collector. The Sn-based sodiophilic species effectively reduce the Na nucleation overpotential and regulate the dendrite Na-free deposition. While the flexible PI columns act as binder and buffer the volume variation of Na during cycling. Besides, the unique patterned structure provides continuous and rapid channels for ion transportation, promoting the Na+ transport kinetics. Therefore, the as-fabricated Sn@LIG@Cu electrode exhibits outstanding rate performance to 40 mA cm-2 and excellent cycling stability without dendrite growth, which is confirmed by in-situ optical microscopy observation. Moreover, the practical full cell based on such an anode displays a favorable rate capability of up to 10 C and cycling performance at 5 C for 600 cycles. This work thus demonstrates a facile, highly-efficient, and scalable approach to stabilize SMAs and can be extended to other battery systems.
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OBJECTIVE: The aim of this study was to evaluate the impact of peer role-playing on the clinical skills performance of pediatric trainees. METHODS: Seventy-eight clinical medicine trainees were randomly divided into a role-playing group and a traditional teaching group, with 39 students in each group. The role-playing group alternated between the roles of clinicians and patients, while the traditional teaching group received the bedside teaching mode of verbal instruction. After two weeks traineeship, mini-Clinical Evaluation Exercise(Mini-CEX) was used to evaluate the trainees' competence in physician-patient communication and clinical practice. A questionnaire was given to the role-playing group to assess their satisfaction with the method. RESULTS: The Mini-CEX scores showed that the role-playing group had superior clinical skills (p < 0.05), including communication, history taking, professionalism, organization, clinical skills, and physical examination, compared to the traditional teaching group. Furthermore, trainee satisfaction was high with the role-playing method,and the satisfaction were more than 95%. CONCLUSION: The role-playing method effectively improved the clinical skills of pediatric trainees, developed clinical communication skills, and enhanced the application of medical knowledge in a simulated medical environment.
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Competencia Clínica , Medicina Clínica , Humanos , Niño , Comunicación , Ejercicio Físico , ConocimientoRESUMEN
BACKGROUND. Use of upper gastrointestinal (UGI) series to diagnose UGI obstruction in neonates and infants has raised concern about increased radiation sensitivity of developing organs. OBJECTIVE. The purpose of this study was to assess the diagnostic performance of saline-aided ultrasound (US) in comparison with UGI series in evaluation for UGI obstruction in neonates and infants. METHODS. In this prospective multicenter study at three hospitals, inpatients were enrolled who were younger than 1 year and had suspected UGI obstruction between June 2015 and May 2018; patients with US evidence of malrotation or pyloric stenosis were ineligible. Enrolled patients underwent both saline-aided US (saline solution administered through a nasogastric tube) and UGI series. Surgical findings or at least 1-year of clinical follow-up findings served as the reference for presence of UGI obstruction. UGI obstruction was classified in terms of level (proximal vs distal) and cause. Two radiologists independently interpreted saline-aided US examinations to assess interobserver agreement and then reached consensus. Two other radiologists assessed upper GI series in consensus. Diagnostic performance for the presence and level of UGI obstruction was compared between modalities. Causes of obstruction were assessed with saline-aided US. RESULTS. A total of 209 neonates were included (116 boys, 93 girls; median age, 5 days; 124 (59.3%) patients had UGI obstruction (proximal in 108 patients). Saline-aided US had strong interobserver agreement for presence (κ = 0.87) and level (κ = 0.85) of obstruction. For presence of UGI obstruction, accuracy, sensitivity, and specificity were 94.7%, 98.4%, and 89.4% for saline-aided US and 89.5%, 95.2%, and 81.2% for UGI series. For obstruction level, accuracy, sensitivity, and specificity were 90.3%, 97.2%, and 56.3% for saline-aided US versus 87.1%, 92.6%, and 50.0% for UGI series. Accuracy for presence was significantly higher for saline-aided US (p = .02); otherwise, these metrics were not different between tests (p > .05). For causes of UGI obstruction (annular pancreas, duodenal web, duodenal atresia, and duodenal stenosis), the accuracy of saline-aided US ranged from 75.0% to 95.2%. CONCLUSION. Saline-aided US has high diagnostic performance for presence and level of UGI obstruction in neonates and infants, comparing favorably with UGI series. Saline-aided US may have additional utility in evaluating causes of obstruction. CLINICAL IMPACT. Saline-aided US may serve as an initial screening modality for UGI obstruction in neonates and infants. TRIAL REGISTRATION. Chinese Clinical Trial Registry ChiCTR-DCC-15006232.
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Tracto Gastrointestinal/diagnóstico por imagen , Obstrucción Intestinal/diagnóstico por imagen , Solución Salina/administración & dosificación , Ultrasonografía/métodos , Femenino , Humanos , Recién Nacido , Masculino , Estudios ProspectivosRESUMEN
The stability of large ligated copper(I) clusters of undeca- and dodecanuclearity encapsulating iodide and stabilized by dithio- and diseleno-phosph(in)ates was investigated by density functional theory (DFT) calculations. A bonding analysis is provided, which shows strong iono-covalent bonding between the iodide and its host. The electronic structures of the title compounds suggest the possibility for interesting photoluminescent properties, which were fully investigated by time-dependent DFT calculations including vibronic contributions to simulate the phosphorescence spectra. The quantum mechanical results were compared to the experimental data obtained for the new clusters [Cu11(µ9-I)(µ3-I)3{Se2P(OiPr)2}6]+ and [Cu11(µ9-I)(µ3-I)3(Se2PPh2)6]+, whose syntheses, X-ray structures, and full characterizations are reported in this paper. From this combined theoretical/experimental investigation, it is suggested that the encapsulation by the same copper(I) cages of a formally Cu- anion is also possible. DFT calculations on these species are consistent with the existence of stable two-electron superatoms.
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BACKGROUND AND OBJECTIVE: Spinal muscular atrophy (SMA) is one of the most common monogenic neuromuscular diseases, and the pathogenesis mechanisms, especially the brain network topological properties, remain unknown. This study aimed to use individual-level morphological brain network analysis to explore the brain neural network mechanisms in SMA. METHODS: Individual-level gray matter (GM) networks were constructed by estimating the interregional similarity of GM volume distribution using both Kullback-Leibler divergence-based similarity (KLDs) and Jesen-Shannon divergence-based similarity (JSDs) measurements based on Automated Anatomical Labeling 116 and Hammersmith 83 atlases for 38 individuals with SMA types 2 and 3 and 38 age- and sex-matched healthy controls (HCs). The topological properties were analyzed by the graph theory approach and compared between groups by a nonparametric permutation test. Additionally, correlation analysis was used to assess the associations between altered topological metrics and clinical characteristics. RESULTS: Compared with HCs, although global network topology remained preserved in individuals with SMA, brain regions with altered nodal properties mainly involved the right olfactory gyrus, right insula, bilateral parahippocampal gyrus, right amygdala, right thalamus, left superior temporal gyrus, left cerebellar lobule IV-V, bilateral cerebellar lobule VI, right cerebellar lobule VII, and vermis VII and IX. Further correlation analysis showed that the nodal degree of the right cerebellar lobule VII was positively correlated with the disease duration, and the right amygdala was negatively correlated with the Hammersmith Functional Motor Scale Expanded (HFMSE) scores. CONCLUSIONS: Our findings demonstrated that topological reorganization may prioritize global properties over nodal properties, and disrupted topological properties in the cortical-limbic-cerebellum circuit in SMA may help to further understand the network pathogenesis underlying SMA.
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Encéfalo , Imagen por Resonancia Magnética , Humanos , Femenino , Masculino , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Adulto , Atrofias Musculares Espinales de la Infancia/patología , Adulto Joven , Adolescente , Sustancia Gris/patología , Sustancia Gris/diagnóstico por imagen , Niño , Red Nerviosa/patología , Red Nerviosa/diagnóstico por imagenRESUMEN
Background: Hemolytic disease of the fetus and newborn (HDFN) due to red cell alloimmunization, is an important cause of fetal and neonatal morbidity and mortality. However, fetal and neonatal outcome of HDFN managed with intrauterine transfusion (IUT) in China are unknown. In addition, fetal and neonatal outcomes according to the type of maternal red cell alloantibodies involved and outcomes of hydrops fetalis are also unclear. Objectives: The objective of this study was to evaluate fetal and neonatal outcomes of severe red-cell alloimmunization treated by IUT, to compare the outcomes according to the type of antibody, and to investigate the perinatal and postnatal outcomes of hydrops fetalis due to red cell alloimmunization. Methods: A retrospective study of pregnancies affected by HDFN and managed with IUT at a tertiary care university hospital in China between January 2001 and December 2018 was performed. Fetal and neonatal outcomes were investigated, and comparison of outcomes depending on the type of antibody and comparison of outcome between hydrops fetalis and fetuses without hydrops were also conducted. Results: 244 IUTs were performed in 81 fetuses from 80 pregnancies. Anti-RhD was the major etiology of HDFN requiring IUT (71.6%). The fetal survival rate was 90.1%. The survival rate of the hydropic fetuses was significantly lower than those of the non hydropic fetuses (61.2% vs. 95.6%) (P = 0.002**). Compared with non hydropic fetuses, hydropic fetuses had significantly lower gestational age and lower hemoglobin level at first IUT. The neonatal survival rate was 98.6%. Exchange transfusions were required in 26% of the neonates. 30.1% of neonates had late anemia and required top-up transfusions, and hydropic fetuses required more late top-up transfusions than fetuses without hydrops. No significant difference in fetal and neonatal outcomes was found among the four subgroups stratified by the antibody involved. Conclusion: Our study demonstrates that IUT is an effective and safe therapy for severe HDFN at our institution. Early detection and treatment of hydrops is critical for perinatal outcomes. Particular attention should be paid to late postnatal anemia in affected neonates and top-up transfusion is still commonly needed.
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Two luminescent, undecanuclear silver complexes [Ag(11)(µ(9)-I)(µ(3)-I)(3){E(2)P(O(i)Pr)(2)}(6)](PF(6)) [E = S (yellow), 1; Se (orange), 2], containing the first µ(9)-iodine inscribed at the center of a pentacapped trigonal-prismatic silver skeleton, were reported.
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Background: Pediatric oncology patients with acute respiratory distress syndrome (ARDS) secondary to pneumonia are at high risk of mortality. Our aim was to describe the epidemiology of ARDS in this clinical population and to identify the association between the oxygenation status at 24 h after diagnosis and the 30-day mortality rates, stratified by the severity of ARDS. Methods: This was a retrospective cohort study of 82 pediatric oncology patients, with a median age of 4 years, admitted to our pediatric intensive care unit with a diagnosis of ARDS between 2013 and 2021. Demographic and clinical factors were compared between the survivor (n = 52) and non-survivor (n = 30) groups. Univariate and multivariate Cox proportional hazards regression models were used to determine the association between the oxygenation status at 24 h after diagnosis and the 30-day mortality rates. Results: The mean airway pressure at ARDS diagnosis, PaO2/FiO2 (P/F) ratio, oxygenation index (OI) value, peak inspiratory pressure, and lactate level at 24 h after ARDS diagnosis, as well as complications (i.e., septicemia and more than two extrapulmonary organ failures) and adjunctive continuous renal replacement therapy, were significant mortality risk factors. After adjusting for other covariates, the oxygenation status P/F ratio (Hazard ratio [HR] = 0.98, 95% confidence interval [CI] = 0.96-1.00, P = 0.043) and OI value (HR = 1.12, 95% CI = 1.02-1.23, P = 0.016) at 24 h remained independent mortality risk factors. According to the Kaplan-Meier survival curve, a low P/F ratio (≤ 150) and high OI (>10) were associated with a higher risk of 30-day mortality (50.9 and 52.9%, respectively; both P < 0.05). Conclusion: The P/F ratio and OI value measured at 24 h after ARDS diagnosis can provide a better stratification of patients according to ARDS disease severity to predict the 30-day mortality risk.
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Room temperature sodium-sulfur (RT Na-S) batteries are considered a promising candidate for energy-storage due to their high energy-density and low-cost. However, the shutting effect of polysulfides and sluggish kinetics of sulfur redox reactions still severely limit their practical implementation. Herein, a new type of 3D hierarchical porous carbonaceous nanocubes is reported as efficient sulfur hosts, composed of carbon nanotubes (CNT) and Co nanoparticles (NPs) uniformly embedded into a nitrogen-doped carbon matrix (NC). Because of the high specific surface area, large degree of graphitization, and the synergetic effects between Co NPs and N-doping, the as-designed CNTs/Co@NC electrodes not only significantly increase polysulfides immobilization, but also efficiently catalyze sulfur redox reactions, as confirmed by experimental results and DFT calculations. When tested in a RT Na-S battery, the S@CNTs/Co@NC-0.25 cathode demonstrates outstanding electrochemical performance, achieving high initial specific capacity of 1200.3 mAh g-1 at 0.1 C, remarkable rate capability up to 5.0 C (474.2 mAh g-1 ), and superior cyclic performance of 450.5 mAh g-1 (292 mAh g-1 ) after 400 cycles at 1.0 C (5.0 C). The integration of a 3D hierarchical porous architecture with well-dispersed Co NPs of an electro-catalyst provides valuable insights based on structure-adsorption-catalysis engineering for advanced RT Na-S batteries.
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Uncontrollable growth of sodium dendrites during the sodium deposition and stripping processes remains a huge challenge for achieving high-performance sodium metal batteries (SMBs), which results in ineffective utilization of metallic Na, low Coulombic efficiency, and inferior cycling life. Here, a single Co atom uniformly decorated porous nitrogen-doped carbon polyhedron (CoSA @NC) matrix has been fabricated and introduced to control the Na growth and achieve uniform Na nucleation/deposition. Cryo-electron microscopy and in situ optical microscopy techniques have been utilized to analyze the morphology change of metallic Na during plating/stripping processes. The single Co atoms evenly embedded in NC electrodes can provide stable Na-philic sites for Na ions adsorption, which is helpful to guide the uniform sodium deposition and prevent Na dendrites growth. This work thus provides an effective solution to inhibit Na dendrite growth and control Na nucleation behavior from the perspective of atomic level, towards the fabrication of high-safety and long-cycling SMBs.
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PURPOSE: This study aimed to describe sac ligation and sequential closure for the management of giant omphalocele (GO) and analyze its outcomes. METHODS: The medical records of 13 neonates with GO treated at a tertiary general hospital between July 2012 and April 2020 were reviewed. Sac ligation and progressive external compression were performed on most cases immediately after birth. Staged closure with or without a prosthetic patch was conducted after a period of sac suspension. RESULTS: Sac ligation-traction-compression was performed on 12 cases, of which 10 underwent staged closure, one with delayed closure. One patient with coexistent esophageal atresia was deemed ineligible for surgery. Among those who had undergone staged closure, 9 survived; however, one neonate who complicated with bilateral diaphragmatic eventration and severe ventilator-associated pneumonia died from multiple-organ failure. Pentalogy of Cantrell was excluded. One patient in whom primary closure was performed after birth died aged 29 h. Pneumonia was the most common infection among patients (5/13), with three having ventilator-associated pneumonia. The median durations of mechanical ventilation and hospital stay were 22.2 days (range, 1-151) and 44.2 days (range, 2-152), respectively, and 25.6 days and 46.4 days, respectively, among patients with staged closure. Among five infants who required oxygen support for more than 28 days, four had pulmonary hypoplasia. CONCLUSIONS: Aside from abdominal wall defects, other major comorbidities and pulmonary hypoplasia influence the prognosis of GO. Sac ligation and staged closure is a effective choice for GO. TYPE OF STUDY: Retrospective Study Level of Evidence: Level IV.
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Hernia Umbilical , Hernia Umbilical/cirugía , Humanos , Lactante , Recién Nacido , Tiempo de Internación , Ligadura , Estudios Retrospectivos , Técnicas de Cierre de HeridasRESUMEN
Potassium-ion batteries (KIBs) have gained significant interest in recent years from the battery research community because potassium is an earth-abundant and redox-active metal, thus having the potential to replace lithium-ion batteries for sustainable energy storage. However, the current development of KIBs is critically challenged by the lack of competitive electrode materials that can reversibly store large amounts of K+ and electrolyte systems that are compatible with the electrode materials. Here, we report that cobalt monochalcogenide (CoSe) nanoparticles confined in N-doped carbon nanotubes (CoSe@NCNTs) can be used as a K+-storing electrode. The CoSe@NCNT composite exhibits a high initial Columbic efficiency (95%), decent capacity (435 mAh g-1 at 0.1 A g-1), and stability (282 mAh g-1 2.0 A g-1 after 500 cycles) in a 1 M KPF6-DME electrolyte with K as the anode over the voltage range from 0.01 to 3.0 V. A full KIB cell consisting of this anode and a Prussian blue cathode also shows excellent electrochemical performance (228 mAh g-1 at 0.5 A g-1 after 200 cycles). We show that the NCNT shell is effective not only in providing high electronic conductivity for fast charge transfer but also in accommodating the volume changes during cycling. We also provide experimental and theoretical evidence that KPF6 in the electrolyte plays a catalytic role in promoting the formation of a polymer-like film on the CoSe surface during the initial activation process, and this amorphous film is of critical importance in preventing the dissolution of polyselenide intermediates into the electrolyte, stabilizing the Co0/K2Se interface, and realizing the reversibility of Co0/K2Se conversion.
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Antioxidant activity is one of the important probiotic characteristics for lactic acid bacteria including Lactobacillus plantarum, which is used for food fermentation or as a probiotic supplement. L. plantarum FLPL05 is a novel strain originally isolated from a healthy elderly individual of longevity. The organism has been demonstrated to exhibit high antioxidant property. However, there are limited genomic insights into the antioxidant properties of this organism. In this study, we performed whole-genome analysis regarding its antioxidant property. L. plantarum FLPL05 exhibited higher antioxidant activity compared with that of L. plantarum strains ATCC14917, ATCC8014, and WCFS1. The antioxidant capacity of L. plantarum FLPL05 was genetically linked to its antioxidant system, i.e., glutathione and thioredoxin involved in global regulation of defense against hydrogen peroxide challenge. L. plantarum FLPL05 was further examined for its antioxidant potential in D-Gal-induced aging mice and exhibited a significant increase in the activity of serum glutathione peroxidase (GSH-PX) and a decrease in the level of malondialdehyde (MDA). Moreover, our analyses exhibited a complete gene cluster including plnA, plnB, plnC, plnD, plnE, plnF, plnG, plnH, plnI, plnJ, plnK, plnM, plnN, plnO, plnP, plnQ, plnST, plnU, plnV, plnW, plnX, and plnY for production of bacteriocin. Our results suggest that L. plantarum FLPL05 could be a probiotic candidate.
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Envejecimiento/genética , Antioxidantes/metabolismo , Microbioma Gastrointestinal/genética , Genoma Bacteriano , Lactobacillus plantarum/genética , Probióticos/farmacología , Anciano de 80 o más Años , Envejecimiento/efectos de los fármacos , Envejecimiento/metabolismo , Animales , Bacteriocinas/biosíntesis , Supervivencia Celular/efectos de los fármacos , Técnicas de Cocultivo , Galactosa/farmacología , Glutatión/metabolismo , Glutatión Peroxidasa/genética , Glutatión Peroxidasa/metabolismo , Células HT29 , Humanos , Peróxido de Hidrógeno/antagonistas & inhibidores , Peróxido de Hidrógeno/farmacología , Lactobacillus plantarum/efectos de los fármacos , Lactobacillus plantarum/aislamiento & purificación , Lactobacillus plantarum/metabolismo , Masculino , Malondialdehído/metabolismo , Ratones , Ratones Endogámicos BALB C , Familia de Multigenes , Probióticos/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismoRESUMEN
Introduction: Clostridium difficile infection (cdi) often occurs with long-term and irregular use of antibiotics. Patients with tumors receiving both antibiotics and chemotherapy are at a high risk of cdi. The symptoms of cdi vary but can include diarrhea, hypovolemia, electrolyte imbalance, hypoproteinemia, toxic megacolon, gastrointestinal tract perforation, disseminated intravascular coagulation, sepsis, and other lethal complications. Here, we report a rare clinical manifestation associated with cdi in a child with lymphoma presenting with massive hydrothorax and ascites. Case Presentation: A 6-year-old girl who was on chemotherapy for lymphoma presented with fever and was treated with intravenous broad-spectrum antibiotics 3 days before admission to our hospital. On the day before admission, she developed abdominal distension and diarrhea. After admission, broad-spectrum antibiotic therapy was initiated, and her hydrothorax and ascites were drained. An initial extensive microbiological evaluation revealed no pathogens, and laboratory tests and imaging studies of the pleural and peritoneal effusions revealed no evidence of cancer. The initial culture results for C. difficile were negative. The patient was diagnosed with CDI only after a positive test result for C. difficile toxin B gene and a repeated stool culture test revealed CDI. Intravenous antibiotics were suspended and replaced with oral vancomycin and Saccharomyces boulardii, which resulted in successful treatment and a good post-discharge outcome. Conclusions: Massive hydrothorax and ascites are rare manifestations associated with CDI. CDI can occur in individuals with risk factors such as those undergoing broad-spectrum antibiotic therapy.
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Background The recommended dose of rasburicase is quite expensive, thus limiting its use. Whether a lower dose of rasburicase would be equally effective for critically ill children, who often have more complicated situations and a higher risk of hospital death, is still unknown. Objective To explore the safety and efficacy of low-dose rasburicase in critically ill children with haematological malignancies who are at high risk of tumour lysis syndrome. Setting A single-centre retrospective cohort study. Method Children with haematological malignancies who had a history of rasburicase exposure during an intensive care unit stay were enrolled. Patients were divided into two groups according to the initial dosage of rasburicase: the standard-dose group (> 0.1 mg/kg/day) and the low-dose group (≤ 0.1 mg/kg/day). The adverse events and short-term prognosis of the two groups were compared. Results Thirty-seven children were selected, 22 in the standard-dose group and 15 in the low-dose group. The most common tumour type was Burkitt's lymphoma (81%), followed by acute lymphoblastic leukaemia (11%). All patients were at high risk of tumour lysis syndrome, and 73% of them had 3 or more tumour lysis syndrome risk factors. The uric acid levels of 90% of patients with hyperuricaemia returned to the normal range within 12 h (100% in the standard-dose group and 75% in the low-dose group, P = 0.083). Eighty-four percent of patients presented serious complications, including tumour lysis syndrome (73%), acute kidney injury (59%), renal replacement treatment (24%), respiratory failure (24%), disseminated intravascular coagulation (16%) and heart failure (11%). There was no significant difference in the incidence of serious complications between the two groups. The overall 7-day and 28-day survival rates after intensive care unit admission were 86% and 84%, respectively. The average length of stay in the intensive care unit was 9.92 ± 5.13 days. Neither the short-term mortality nor the length of stay in the intensive care unit were significantly different between the two groups. Conclusion Low-dose rasburicase is effective and may be an acceptable choice for critically ill children with haematological malignancies.
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Antineoplásicos/efectos adversos , Supresores de la Gota/administración & dosificación , Neoplasias Hematológicas/tratamiento farmacológico , Hiperuricemia/prevención & control , Síndrome de Lisis Tumoral/prevención & control , Urato Oxidasa/administración & dosificación , Factores de Edad , Niño , Preescolar , Enfermedad Crítica , Femenino , Supresores de la Gota/efectos adversos , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/mortalidad , Mortalidad Hospitalaria , Humanos , Hiperuricemia/diagnóstico , Hiperuricemia/etiología , Hiperuricemia/mortalidad , Unidades de Cuidado Intensivo Pediátrico , Tiempo de Internación , Masculino , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Síndrome de Lisis Tumoral/diagnóstico , Síndrome de Lisis Tumoral/etiología , Síndrome de Lisis Tumoral/mortalidad , Urato Oxidasa/efectos adversosRESUMEN
In spite of the great potential in leading next-generation energy storage technology, Li-S batteries suffer rapid capacity decay arising from the shuttling effect of lithium polysulfides (LiPSs), a major concern that must be addressed before commercialization can be realized. To tackle this challenge, we demonstrate a facile approach to fabricate a hierarchically structured composite of Fe2P@nitrogen, phosphorus codoped carbon (Fe2P@NPC) by direct biological recycling of iron metal from electroplating sludge using bacteria. This material, featuring uniform dispersion of Fe2P nanoparticles (NPs) in porous NPC matrix, effectively adapts volume variation of sulfur upon cycling and simultaneously provides multiple channels for efficient lithium ion transport. In addition, Fe2P NPs with strong adhesion properties of tightly anchored soluble LiPSs formed during discharge can significantly facilitate the decomposition of Li2S during the subsequent charging process. The Li-S cell built on this cathode architecture delivers high specific capacity (1555.7 mAh g-1 at 0.1 C), appreciable rate capability (679.7 mAh g-1 at 10 C), and greatly enhanced cycling performance (761.9 mAh g-1 at 1.0 C after 500 cycles).
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Tunnel-type (T-type) Na0.44MnO2 (NMO) is a promising cathode material for sodium-ion batteries (SIBs) owing to its high rate performance and cycling stability compared to manganese-based layered oxides. However, the low specific capacity still restricts its practical applications. Herein, a Co-doped T-type NMO is synthesized through a facile solid-state reaction method and utilized as a cathode material for SIBs. A T-type Na0.44Mn0.9925Co0.0075O2 (NMO-3) electrode can deliver a high reversible capacity of 138 mAh g-1 at 0.1C, a superior rate capability (133, 130, 121, 106, and 93 mAh g-1 at 0.5, 1, 2, 5, and 10C, respectively), and excellent cycling stability (85.2% at 10C after 500 cycles). The substitution of Co3+ by Mn3+ leads to the enlargement of small and S-shaped tunnel spaces, which facilitates the insertion/deinsertion of Na+ into/from NMO-3 and greatly enhances its rate capability and cycling stability. Moreover, the reduced energy barriers for Na+ diffusion in small tunnels make the inactive Na+ easier to be deintercalated, which should be responsible for its high specific capacity that exceeds the theoretical capacity of T-type NMO.
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Venous ulcers are the most common type of human chronic nonhealing wounds and are stalled in a constant and excessive inflammatory state. The molecular mechanisms underlying the chronic wound inflammation remain elusive. Moreover, little is known about the role of regulatory RNAs, such as microRNAs, in the pathogenesis of venous ulcers. We found that both microRNA (miR)-34a and miR-34c were upregulated in the wound-edge epidermal keratinocytes of venous ulcers compared with normal wounds or the skin. In keratinocytes, miR-34a and miR-34c promoted inflammatory chemokine and cytokine production. In wounds of wild-type mice, miR-34a-mimic treatment enhanced inflammation and delayed healing. To further explore how miR-34 functions, LGR4 was identified as a direct target mediating the proinflammatory function of miR-34a and miR-34c. Interestingly, impaired wound closure with enhanced inflammation was also observed in Lgr4 knockout mice. Mechanistically, the miR-34-LGR4 axis regulated GSK-3ß-induced p65 serine 468 phosphorylation, changing the activity of the NF-κB signaling pathway. Collectively, the miR-34-LGR4 axis was shown to regulate keratinocyte inflammatory response, the deregulation of which may play a pathological role in venous ulcers.
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MicroARNs/metabolismo , Receptores Acoplados a Proteínas G/genética , Úlcera Varicosa/inmunología , Cicatrización de Heridas/genética , Anciano , Anciano de 80 o más Años , Animales , Biopsia , Movimiento Celular/genética , Movimiento Celular/inmunología , Proliferación Celular/genética , Modelos Animales de Enfermedad , Femenino , Regulación de la Expresión Génica/inmunología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Voluntarios Sanos , Humanos , Queratinocitos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Fosforilación/genética , Fosforilación/inmunología , Transducción de Señal/genética , Transducción de Señal/inmunología , Piel/inmunología , Piel/patología , Factor de Transcripción ReIA/metabolismo , Úlcera Varicosa/patología , Cicatrización de Heridas/inmunologíaRESUMEN
We propose programed potential modulation strategies to balance the ion intercalation/deintercalation, surface tailoring and bubbling dispersion processes in the electrochemical exfoliation of graphite, resulting in high-quality graphene with high crystallinity, low oxidation degree, uniform size distribution and few layers.
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Dendrite growth of alkali metal anodes limited their lifetime for charge/discharge cycling. Here, we report near-perfect anodes of lithium, sodium, and potassium metals achieved by electrochemical polishing, which removes microscopic defects and creates ultra-smooth ultra-thin solid-electrolyte interphase layers at metal surfaces for providing a homogeneous environment. Precise characterizations by AFM force probing with corroborative in-depth XPS profile analysis reveal that the ultra-smooth ultra-thin solid-electrolyte interphase can be designed to have alternating inorganic-rich and organic-rich/mixed multi-layered structure, which offers mechanical property of coupled rigidity and elasticity. The polished metal anodes exhibit significantly enhanced cycling stability, specifically the lithium anodes can cycle for over 200 times at a real current density of 2 mA cm-2 with 100% depth of discharge. Our work illustrates that an ultra-smooth ultra-thin solid-electrolyte interphase may be robust enough to suppress dendrite growth and thus serve as an initial layer for further improved protection of alkali metal anodes.