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Delta like non-canonical Notch ligand 1 (DLK1), as a member of epidermal growth factor-like family, plays a critical role in somatic growth, tissue development and possibly tissue renewal. Though previous studies had indicated that DLK1 contributed to adipogenesis and myogenesis, it's still controversial whether DLK1 affects angiogenesis and how it interacts with Notch signaling with numerous conflicting reports from different models. Based on our preliminary finding that DLK1 expression was up-regulated in mice ischemic gastrocnemius and in the border zone of infarcted myocardium, we administered either recombinant DLK1 (rDLK1) or PBS in C57BL/6 mice after establishment of hindlimb ischemia (HLI) and myocardial infarction (MI), respectively. Exogenous rDLK1 administration significantly improved both blood perfusion of mice ischemic hindlimbs and muscle motor function on the 3rd, 7th day after HLI, by promoting neovascularization. Similar effect on neovascularization was verified in mice on the 28th day after MI as well as improvement of cardiac failure. Correspondingly, the number of CD34+KDR+ cells, indicated as endothelial progenitor cells (EPCs), was significantly in mice ischemic gastrocnemius by rDLK1 administration, which was abrogated by DAPT as the specific inhibitor of Notch intracellular domain (NICD). Furthermore, bone marrow mononuclear cells were obtained from C57BL/6 mice and differentiated to EPCs ex vivo. Incubation with rDLK1 triggered Notch1 mRNA and NICD protein expressions in EPCs as exposed to hypoxia and serum deprivation, promoting EPCs proliferation, migration, anti-apoptosis and tube formation. Otherwise, rDLK1 incubation significantly decreased intracellular and mitochondrial reactive oxygen species, increased ATP content and mitochondrial membrane potential, downregulated short isoform of OPA-1 expression whereas upregulated mitofusin (-1, -2) expression in EPCs by Notch1 signaling, which were all abrogated by DAPT. In summary, the present study unveils the pro-angiogenesis and its mechanism of rDLK1 through activation of Notch1 signaling in endothelial progenitor cells.
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A substantial proportion of diabetic patients suffer a debilitating and persistent pain state, known as peripheral painful neuropathy that necessitates improved therapy or antidote. Purpurin, a natural anthraquinone compound from Rubia tinctorum L., has been reported to possess antidepressant activity in preclinical studies. As antidepressants have been typically used as standard agents against persistent neuropathic pain, this study aimed to probe the effect of purpurin on neuropathic pain associated with streptozotocin-induced type 1 diabetes in male C57BL6J mice. The Hargreaves test and the von Frey test were used to assess the pain-like behaviors, shown as heat hyperalgesia and mechanical allodynia respectively. Chronic treatment of diabetic mice with purpurin not only ameliorated the established symptoms of heat hyperalgesia and mechanical allodynia, but also arrested the development of these pain states given preemptively at low doses. Although purpurin treatment hardly impacted on metabolic disturbance in diabetic mice, it ameliorated exacerbated oxidative stress in pain-associated tissues, improved mitochondrial bioenergetics in dorsal root ganglion neurons and restored nerve conduction velocity in sciatic nerves. Notably, the analgesic actions of purpurin were modified by pharmacologically manipulating redox status and mitochondrial bioenergetics. These findings unveil the analgesic activity of purpurin, an effect that is causally associated with its bioenergetics-enhancing and antioxidant effects, in mice with type 1 diabetes.
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Antraquinonas , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Metabolismo Energético , Hiperalgesia , Camundongos Endogâmicos C57BL , Mitocôndrias , Neuralgia , Neurônios , Oxirredução , Animais , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/tratamento farmacológico , Metabolismo Energético/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Antraquinonas/farmacologia , Antraquinonas/uso terapêutico , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neuropatias Diabéticas/tratamento farmacológico , Neuropatias Diabéticas/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Nervo Isquiático/efeitos dos fármacos , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Analgésicos/farmacologia , Analgésicos/uso terapêuticoRESUMO
AIMS: Although there are various model-based approaches to individualized vancomycin (VCM) administration, few have been reported for adult patients with periprosthetic joint infection (PJI). This work attempted to develop a machine learning (ML)-based model for predicting VCM trough concentration in adult PJI patients. METHODS: The dataset of 287 VCM trough concentrations from 130 adult PJI patients was split into a training set (229) and a testing set (58) at a ratio of 8:2, and an independent external 32 concentrations were collected as a validation set. A total of 13 covariates and the target variable (VCM trough concentration) were included in the dataset. A covariate model was respectively constructed by support vector regression, random forest regression and gradient boosted regression trees and interpreted by SHapley Additive exPlanation (SHAP). RESULTS: The SHAP plots visualized the weight of the covariates in the models, with estimated glomerular filtration rate and VCM daily dose as the 2 most important factors, which were adopted for the model construction. Random forest regression was the optimal ML algorithm with a relative accuracy of 82.8% and absolute accuracy of 67.2% (R2 =.61, mean absolute error = 2.4, mean square error = 10.1), and its prediction performance was verified in the validation set. CONCLUSION: The proposed ML-based model can satisfactorily predict the VCM trough concentration in adult PJI patients. Its construction can be facilitated with only 2 clinical parameters (estimated glomerular filtration rate and VCM daily dose), and prediction accuracy can be rationalized by SHAP values, which highlights a profound practical value for clinical dosing guidance and timely treatment.
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In spite of the competitive performance at room temperature, the development of sodium-ion batteries (SIBs) is still hindered by sluggish electrochemical reaction kinetics and unstable electrode/electrolyte interphase under subzero environments. Herein, a low-concentration electrolyte, consisting of 0.5M NaPF6 dissolving in diethylene glycol dimethyl ether solvent, is proposed for SIBs working at low temperature. Such an electrolyte generates a thin, amorphous, and homogeneous cathode/electrolyte interphase at low temperature. The interphase is monolithic and rich in organic components, reducing the limitation of Na+ migration through inorganic crystals, thereby facilitating the interfacial Na+ dynamics at low temperature. Furthermore, it effectively blocks the unfavorable side reactions between active materials and electrolytes, improving the structural stability. Consequently, Na0.7Li0.03Mg0.03Ni0.27Mn0.6Ti0.07O2//Na and hard carbon//Na cells deliver a high capacity retention of 90.8 % after 900 cycles at 1C, a capacity over 310â mAh g-1 under -30 °C, respectively, showing long-term cycling stability and great rate capability at low temperature.
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Objective: The study established a nomogram based on quantitative parameters of spectral computed tomography (CT) and clinical characteristics, aiming to evaluate its predictive value for preoperative lymphovascular invasion (LVI) in gastric cancer (GC). Methods: From December 2019 to December 2021, 171 patients with pathologically confirmed GC were retrospectively collected with corresponding clinical data and spectral CT quantitative data. Patients were divided into LVI-positive and LVI-negative groups based on their pathological results. The univariate and multivariate logistic regression analyses were used to identify the risk factors and construct a nomogram. The calibration curve and receiver operating characteristic (ROC) curve were adopted to evaluate the predictive accuracy of nomogram. Results: Four clinical characteristics or spectral CT quantitative parameters, including Borrmann classification (P = 0.039), CA724 (P = 0.007), tumor thickness (P = 0.031), and iodine concentration in the venous phase (VIC) (P = 0.004) were identified as independent factors for LVI in GC patients. The nomogram was established based on the four factors, which had a potent predictive accuracy in the training, internal validation and external validation cohorts, with the area under the ROC curve (AUC) of 0.864 (95% CI, 0.798-0.930), 0.964 (95% CI, 0.903-1.000) and 0.877 (95% CI, 0.759-0.996), respectively. Conclusion: This study constructed a comprehensive nomogram consisting spectral CT quantitative parameters and clinical characteristics of GC, which exhibited a robust efficiency in predicting LVI in GC patients.
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BACKGROUND: Ginkgo biloba L. preparations (GBLPs) are a class of Chinese herbal medicine used in the adjuvant treatment of ischemic stroke (IS). Recently, several systematic reviews (SRs) and meta-analyses (MAs) of GBLPs for IS have been published. OBJECTIVE: This overview aims to assess the quality of related SRs and MAs. SEARCH STRATEGY: PubMed, Embase, Cochrane Library, Web of Science, Chinese Biological Medicine, China National Knowledge Infrastructure, Wanfang, and Chinese Science and Technology Journals databases were searched from their inception to December 31, 2022. INCLUSION CRITERIA: SRs and MAs of randomized controlled trials (RCTs) that explored the efficacy of GBLPs for patients with IS were included. DATA EXTRACTION AND ANALYSIS: Two independent reviewers extracted data and assessed the methodological quality, risk of bias (ROB), reporting quality, and credibility of evidence of the included SRs and MAs using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), Risk of Bias in Systematic Reviews (ROBIS), the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA), and the Grading of Recommendations Assessment, Development and Evaluation (GRADE), respectively. Additionally, descriptive analysis and data synthesis were conducted. RESULTS: Twenty-nine SRs/MAs involving 119 outcomes were included in this review. The overall methodological quality of all SRs/MAs was critically low based on AMSTAR 2, and 28 had a high ROB based on the ROBIS. According to the PRISMA statement, the reporting items of the included SRs/MAs are relatively complete. The results based on GRADE showed that of the 119 outcomes, 8 were rated as moderate quality, 24 as low quality, and 87 as very low quality. Based on the data synthesis, GBLPs used in conjunction with conventional treatment were superior to conventional treatment alone for decreasing neurological function scores. CONCLUSION: GBLPs can be considered a beneficial supplemental therapy for IS. However, because of the low quality of the existing evidence, high-quality RCTs and SRs/MAs are warranted to further evaluate the benefits of GBLPs for treating IS. Please cite this article as: Meng TT, You YP, Li M, Guo JB, Song XB, Ding JY, Xie XL, Li AQ, Li SJ, Yin XJ, Wang P, Wang Z, Wang BL, He QY. Chinese herbal medicine Ginkgo biloba L. preparations for ischemic stroke: An overview of systematic reviews and meta-analyses. J Integr Med. 2024;22(2): 163-179.
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Medicamentos de Ervas Chinesas , Ginkgo biloba , AVC Isquêmico , Revisões Sistemáticas como Assunto , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , AVC Isquêmico/tratamento farmacológico , Metanálise como Assunto , Fitoterapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Extratos Vegetais/uso terapêutico , Extrato de GinkgoRESUMO
Prussian white (PW) is one of the most promising candidates as a cathode for sodium-ion batteries (SIBs) because of its high theoretical capacity, excellent rate performance, and low production cost. However, PW materials suffer severe capacity decay during long-term cycling. In this work, a robust cathode electrolyte interface (CEI) is designed on the PW cathode by employing cresyl diphenyl phosphate (CDP) and adiponitrile (ADN) as electrolyte additives. CDP and ADN possess higher highest occupied molecular orbital energy levels (HOMO) than other solvents, leading to the preferential decomposition of CDP and ADN to construct an inorganics-rich CEI layer in situ on the PW cathode. Benefiting from this CEI layer, the degradation of PW is effectively inhibited during the long cycling. The Na||PW cell achieves an excellent cycling performance with a capacity retention of 85.62% after 1400 cycles. This work presented here provides a feasible strategy for improving the cycling performance of PW by electrolyte modification.
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Iron-based Prussian white (PW) is one of the promising cathodes for sodium-ion batteries, owing to its high capacity and low cost. However, the practical application of PW is hindered by its poor air stability. The metal-oxide coating has been proven to be an effective way to improve the air stability of electrode materials. Whereas, the target electrode materials conventionally need to be dissolved in the aqueous solution to obtain precursor composites and subsequently calcined at a high temperature during the metal-oxide coating process, which could destroy the phase structure of PW as a result of the sodium leaching into the water and thermal decomposition at the high temperature. In this work, we propose a facile method to construct a ZnO surface layer on PW by utilizing ethanol as a solvent and a mild post-treatment temperature. The ZnO coating layer effectively enhances the air stability of PW and induces the formation of the stable interface on PW. The PW-5 wt % ZnO-E (exposed in 60% humidity air after 30 days) cathode demonstrates a much higher capacity retention (94.1%) at 1 C after 200 cycles than that of PW-E (54%). This work lays a solid foundation for further application of PW.
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The development of thermally stable separators is a promising approach to address the safety issues of lithium-ion batteries (LIBs) owing to the serious shrinkage of commercial polyolefin separators at elevated temperatures. However, achieving controlled nanopores with a uniform size distribution in thermostable polymeric separators and high electrochemical performance is still a great challenge. In this study, nanoporous polyimide (PI) membranes with excellent thermal stability as high-safety separators is developed for LIBs using a superspreading strategy. The superspreading of polyamic acid solutions enables the generation of thin and uniform liquid layers, facilitating the formation of thin PI membranes with controllable and uniform nanopores with narrow size distribution ranging from 121 ± 5 nm to 86 ± 6 nm. Such nanoporous PI membranes display excellent structural stability at elevated temperatures up to 300 °C for at least 1 h. LIBs assembled with nanoporous PI membranes as separators show high specific capacity and Coulombic efficiency and can work normally after transient treatment at a high temperature (150 °C for 20 min) and high ambient temperature, indicating their promising application as high-safety separators for rechargeable batteries.
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INTRODUCTION: Fibrosing mediastinitis is a benign but fatal disorder characterized by the proliferation of fibrous tissue in the mediastinum, causing encasement of mediastinal organs and extrinsic compression of adjacent bronchovascular structures. FM-associated pulmonary hypertension (FM-PH) is a serious complication of FM, resulting from the external compression of lung vessels. Pathologic assessment is important for etiologic diagnosis and effective treatment of this disease. CASE PRESENTATION: A 59-year-old male patient presented at our hospital and was diagnosed with FM-PH. He declined surgical biopsy that is the reference standard for pathologic assessment, in consideration of the potential risks. Therefore, an endobronchial ultrasound examination was performed, which identified the subcarinal lesion. Under ultrasound guidance, four needle aspirations were carried out, followed by one cryobiopsy. Histopathological examination of transbronchial needle aspiration specimens was inconclusive, while samples from cryobiopsy suggested a diagnosis of idiopathic FM. Further immunophenotyping demonstrated the infiltration of lymphocytes, macrophages, and FOXP3-positive cells in FM-PH. CONCLUSION: Mediastinal cryobiopsy might be a novel and safe option for FM-PH patients who are unwilling or unsuitable for surgical procedure.
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Hipertensão Pulmonar , Mediastinite , Hipertensão Arterial Pulmonar , Esclerose , Masculino , Humanos , Pessoa de Meia-Idade , Mediastino , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/complicações , Mediastinite/complicações , Mediastinite/diagnóstico , Hipertensão Arterial Pulmonar/patologiaRESUMO
Despite the high energy of LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) cathode, it still suffers serious decay due to the continuous solvents decomposition and unstable cathode electrolyte interphase (CEI) layers, especially under high temperatures. The intense exothermic reaction between delithiated NCM811 and flammable electrolyte, on the other hand, pushes the batteries to their safety limit. Herein, these two issues are tackled via engineering the electrolytes, that is, utilizing salts with higher HOMO levels and nonflammable solvents with lower HOMO levels, to reduce the massive decomposition of solvents and improve battery safety under elevated temperatures. Consequently, a thin and boron-rich CEI is generated, which effectively inhibited the side reactions, thus improving the cycling stability and safety. Deviated from the highly concentrated electrolytes which heavily relies on the usage of massive salts, the electrolyte recipe can introduce a robust inorganic-rich CEI but use much less salt (i.e., dilute electrolyte), and thus, offer an encouraging alternative toward practical applications. As such, the NCM811 cathode exhibits a high-capacity retention of 81.2% after 950 cycles at 25 °C and 75% after 300 cycles at 55 °C. This work provides a universal electrolyte design strategy for designing stable and safe high-temperature electrolytes for the NCM811 cathode.
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OBJECTIVES: To explore the possible mechanism of Shao's five-needle therapy pretreatment on relieving airway inflammatory response in asthmatic rats. METHODS: Forty SPF-grade SD rats were randomly divided into a blank group, a model group, an acupuncture group, and a medication group, with 10 rats in each group. Except the blank group, asthma model was established by aerosol inhalation of ovalbumin in the other 3 groups. The rats in the acupuncture group were treated with acupuncture at "Dazhui" (GV 14) and bilateral "Feishu" (BL 13) and "Fengmen" (BL 12), with each session lasting for 20 min. Acupuncture was given before each motivating, once daily for 7 consecutive days. The rats in the medication group were treated with intraperitoneal injection of dexamethasone sodium phosphate solution before each motivating, once daily for 7 days. General situation of the rats was observed in each group; ELISA method was used to detect the levels of inflammatory cytokines interleukin (IL)-1ß and IL-18 in serum; immunofluorescence staining method was performed to assess the expression of reactive oxygen species (ROS) in lung tissues; Western blot method was used to measure the protein expression of thioredoxin interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), and Caspase-1 in lung tissues. RESULTS: The rats in the blank group exhibited normal behavior, while those in the model group showed signs of respiratory distress, ear scratching, cheek rubbing, and dysphoria. Compared with the model group, the rats in the acupuncture group and the medication group showed stable respiration and relatively agile responses. Compared with those in the blank group, the serum levels of IL-18 and IL-1ß were elevated (P<0.01), the expression intensity of ROS was increased, and the protein expressions of TXNIP, NLRP3, ASC and Caspase-1 in lung tissues were increased (P<0.01) in the model group. Compared with those in the model group, the serum levels of IL-18 and IL-1ß were reduced (P<0.01), the expression intensity of ROS was lowered, and the protein expressions of TXNIP, NLRP3, ASC and Caspase-1 in lung tissues were reduced (P<0.01) in the acupuncture group and the medication group. Compared with the medication group, the protein expression of ASC in lung tissue was reduced in the acupuncture group (P<0.05). CONCLUSIONS: Pretreatment of Shao's five-needle therapy could alleviate airway inflammatory response in asthmatic rats by reducing ROS levels and decreasing the aggregation and activation of pathway-related proteins in the ROS/TXNIP/NLRP3 pathway, ultimately leading to decreased secretion of IL-1ß and IL-18. This mechanism may contribute to the effectiveness of Shao's five-needle therapy in preventing and treating asthma.
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Asma , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Interleucina-18/genética , Interleucina-18/metabolismo , Proteínas NLR , Ratos Sprague-Dawley , Asma/genética , Asma/terapia , Asma/metabolismo , Caspases , Proteínas de Ciclo CelularRESUMO
Background: Cone-rod dystrophy (CORD) caused by pathogenic variants in CFAP410 is a very rare disease. The mechanisms by which the variants caused the disease remained largely unknown. CFAP410 pathogenic variants were identified in a cone-rod dystrophy with macular staphyloma patient. We explored the pathogenicity and performed functional analysis of two compound heterozygous mutations. Methods: A 6-year-old boy complained decreased vision for 1 year, underwent ocular examinations together with systemic X-ray check. Blood sample was taken for targeted next generation sequencing (Tg-NGS). Pathogenicity of identified variants was determined by ACMG guideline. Mutated plasmids were constructed and transferred to HEK293T cells. Cell cycle, protein stability, and protein ubiquitination level was measured. Results: The best-corrected visual acuity of proband was 0.20 bilaterally. Fundus showed macular staphyloma and uneven granular pigment disorder in the periphery of the retina. SS-OCT showed thinning and atrophy of the outer retina, residual ellipsoid zone (EZ) in the fovea. Scotopic and photopic ERG responses severe reduced. Two heterozygous missense pathogenic variants, c.319 T > C (p.Tyr107His) and c.347 C > T (p.Pro116Leu) in exon 4 of the CFAP410, were found and were pathogenic by the ACMG guideline. In vitro, pathogenic variants affect cell cycle. Immunofluorescence and western blotting showed that the mutant proteins decreased expression levels protein stability. Meanwhile, co-IP data suggested that ubiquitination level was altered in cells transferred with the mutated plasmids. Conclusion: Compound heterozygous pathogenic variants c.319 T > C and c.347 C > T in CFAP410 caused CORD with macular staphyloma. The pathogenic mechanisms may be associated with alternations of protein stability and degradation through the ubiquitin-proteasome pathway.
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Purpose: The purpose of this study was to explore the pathogenicity and function of two novel SLC4A11 variants associated with congenital hereditary endothelial dystrophy (CHED) and to study the function of a SLC4A11 (K263R) mutant in vitro. Methods: Ophthalmic examinations were performed on a 28-year-old male proband with CHED. Whole-exome and Sanger sequencing were applied for mutation screening. Bioinformatics and pathogenicity analysis were performed. HEK293T cells were transfected with the plasmids of empty vector, wild-type SLC4A11, and SLC4A11 (K263R) mutant. The transfected cells were treated with SkQ1. Oxygen consumption, cellular reactive oxygen species (ROS) level, mitochondrial membrane potential, and apoptosis rate were measured. Results: The proband had poor visual acuity with nystagmus since childhood. Corneal foggy opacity was evident in both eyes. Two novel SLC4A11 variants were detected. Sanger sequencing showed that the proband's father and sister carried c.1464-1G>T variant, and the proband's mother and sister carried c.788A>G (p.Lys263Arg) variant. Based on the American College of Medical Genetics (ACMG) guidelines, SLC4A11 c.1464-1G>T was pathogenic, whereas c.788A>G, p.K263R was a variant of undetermined significance. In vitro, SLC4A11 (K263R) variant increased ROS level and apoptosis rate. Decrease in mitochondrial membrane potential and oxygen consumption rate were remarkable. Furthermore, SkQ1 decreased ROS levels and apoptosis rate but increased mitochondrial membrane potential in the transfected cells. Conclusions: Two novel heterozygous pathogenic variants of the SLC4A11 gene were identified in a family with CHED. The missense variant SLC4A11 (K263R) caused mitochondrial dysfunction and increased apoptosis in mutant transfected cells. In addition, SkQ1 presented a protective effect suggesting the anti-oxidant might be a novel therapeutic drug. Translational Relevance: This study verified the pathogenicity of 2 novel variants in the SLC4A11 gene in a CHED family and found an anti-oxidant might be a new drug.
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Antioxidantes , Distrofias Hereditárias da Córnea , Adulto , Criança , Humanos , Masculino , Proteínas de Transporte de Ânions/genética , Antiporters/genética , Distrofias Hereditárias da Córnea/genética , Distrofias Hereditárias da Córnea/patologia , Células HEK293 , Espécies Reativas de Oxigênio , VirulênciaRESUMO
A novel nanocomposite material, ferric vanadate intertwined multi-walled carbon nanotubes (FeV/MWCNTs), has been designed which was drop-coated onto a glassy carbon electrode (GCE). The constructed sensor was used for the sensitive determination of uric acid (UA) in fetal bovine serum (FBS) and human serum (HS). A series of characterization and electrochemical tests showed that the ultrasound-assisted assembly of FeV with MWCNTs not only overcame the disadvantages of low conductivity and easy (unwanted) aggregation, but also avoided the decrease in effective surface area due to the severe aggregation of each individual raw material. The fabricated FeV/MWCNTs nanocomposites exhibited higher conductivity, larger effective surface area, and better electrocatalytic activity. In addition, under optimized conditions, the developed electrochemical sensor FeV/MWCNTs/GCE has a lower limit of detection (LOD, 0.05 µM; Ep = 0.268 V vs. Ag/AgCl) and wider linear range (0.20-100 µM), which can satisfy the criteria of trace UA detection. The results of UA determination in FBS (recovery = 95.5-103%; RSD ≤ 3.1%) and HS (recovery = 95.5-103%; RSD ≤ 4.3%) further validated the feasibility of FeV/MWCNTs-based electrochemical sensors for the determination of UA in biological fluids.
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Nanocompostos , Nanotubos de Carbono , Humanos , Nanotubos de Carbono/química , Soroalbumina Bovina , Ácido Úrico , Vanadatos , Técnicas Eletroquímicas/métodos , Limite de Detecção , Nanocompostos/química , FerroRESUMO
High-capacity O3-type layered sodium oxides are considered one of the most promising cathode materials for the next generation of Na-ion batteries (NIBs). However, these cathodes usually suffer from low high-rate capacity and poor cycling stability due to structure deformation, native air sensitivity, and interfacial side reactions. Herein, a multi-site substituted strategy is employed to enhance the stability of O3-type NaNi0.5 Mn0.5 O2 . Simulations indicate that the Ti substitution decreases the charge density of Ni ions and improves the antioxidative capability of the material. In addition, the synergistic effect of K+ and Ti4+ significantly reduces the formation energy of Na+ vacancy and delivers an ultra-low lattice strain during the repeated Na+ extraction/insertion. In situ characterizations verify that the complicated phase transformation is mitigated during the charge/discharge process, resulting in greatly improved structure stability. The co-substituted cathode delivers a high-rate capacity of 97 mAh g-1 at 5 C and excellent capacity retention of 81% after 400 cycles at 0.5 C. The full cell paired with commercial hard carbon anode also exhibits high capacity and long cycling life. This dual-ion substitution strategy will provide a universal approach for the new rational design of high-capacity cathode materials for NIBs.
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Natrium superionic conductor (NASICON) is a promising solid-state electrolyte because of its high stability under air as well as its safety. Doping is an effective way to improve its ionic conductivity, but there is limited information about the explanation of the doping sites. In this work, Al-doped NASICONs are designed. When Al doping is 0.3 (NAl0.3ZSP), the ionic conductivity is the highest and is 5.08 × 10-5 S cm-1 at 30 °C, which is 3.3 times that of undoped NASICON. NAl0.3ZSP consists of a NASICON structure (monoclinic and rhombohedral phases), an amorphous glassy phase, and Na3PO4 impurities. After Al doping, more Si/P sites are occupied by Al; thus, the ratio of Na3PO4 impurities increases. Na3PO4 at the grain boundary is beneficial for grain boundary resistance decrease, contributing to the decrease of the total resistance. Our work first provides a detailed explanation of doped-Al sites and interprets their effects on ionic conductivity.
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Prussian white (PW) is considered one of the most promising cathode materials for sodium-ion batteries because of its large ion diffusion channels, low lattice strain, facile preparation, nontoxicity, and low cost. At present, research on PW mainly focuses on optimizing the material's structures for the ambient environment yet less on its practical application under extreme temperatures. In this Spotlight, we intend to offer progress we have made in developing PW cathode materials working over wide temperatures in terms of intrinsic feasibility and development prospects. These findings provide a direction to promote the practical viability of PW under extreme conditions.
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A convenient and efficient trans-stereoselective and ß-regioselective hydroboration of propargyl alcohols was achieved simply with LiOtBu as the base and (Bpin)2 as the boron reagent in dimethyl sulfoxide at room temperature. Both terminal and internal propargyl alcohols with diverse structures and functional groups underwent the transformation smoothly to produce ß-Bpin-substituted (E)-allylic alcohols, of which the synthetic potentials were demonstrated by the downstream conversions of boronate, alkenyl, and hydroxyl groups.