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1.
Proc Natl Acad Sci U S A ; 121(8): e2320262121, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38349879

RESUMEN

The human malaria parasite Plasmodium falciparum requires exogenous fatty acids to support its growth during the pathogenic, asexual erythrocytic stage. Host serum lysophosphatidylcholine (LPC) is a significant fatty acid source, yet the metabolic processes responsible for the liberation of free fatty acids from exogenous LPC are unknown. Using an assay for LPC hydrolysis in P. falciparum-infected erythrocytes, we have identified small-molecule inhibitors of key in situ lysophospholipase activities. Competitive activity-based profiling and generation of a panel of single-to-quadruple knockout parasite lines revealed that two enzymes of the serine hydrolase superfamily, termed exported lipase (XL) 2 and exported lipase homolog (XLH) 4, constitute the dominant lysophospholipase activities in parasite-infected erythrocytes. The parasite ensures efficient exogenous LPC hydrolysis by directing these two enzymes to distinct locations: XL2 is exported to the erythrocyte, while XLH4 is retained within the parasite. While XL2 and XLH4 were individually dispensable with little effect on LPC hydrolysis in situ, loss of both enzymes resulted in a strong reduction in fatty acid scavenging from LPC, hyperproduction of phosphatidylcholine, and an enhanced sensitivity to LPC toxicity. Notably, growth of XL/XLH-deficient parasites was severely impaired when cultured in media containing LPC as the sole exogenous fatty acid source. Furthermore, when XL2 and XLH4 activities were ablated by genetic or pharmacologic means, parasites were unable to proliferate in human serum, a physiologically relevant fatty acid source, revealing the essentiality of LPC hydrolysis in the host environment and its potential as a target for anti-malarial therapy.


Asunto(s)
Malaria Falciparum , Parásitos , Animales , Humanos , Plasmodium falciparum , Lisofosfatidilcolinas/metabolismo , Lisofosfolipasa/genética , Lisofosfolipasa/metabolismo , Malaria Falciparum/parasitología , Eritrocitos/metabolismo , Parásitos/metabolismo , Ácidos Grasos/metabolismo , Lipasa/metabolismo , Proteínas Protozoarias/metabolismo
2.
Plant J ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101617

RESUMEN

High temperature (HT) severely restricts plant growth, development, and productivity. Plants have evolved a set of mechanisms to cope with HT, including the regulation of heat stress transcription factors (Hsfs) and heat shock proteins (Hsps). However, it is not clear how the transcriptional and translational levels of Hsfs and Hsps are controlled in tomato. Here, we reported that the HT-induced transcription factor SlWRKY55 recruited SlVQ11 to coordinately regulate defense against HT. SlWRKY55 directly bound to the promoter of SlHsfA2 and promoted its expression, which was increased by SlVQ11. Moreover, both SlWRKY55 and SlVQ11 physically interacted with SlHsfA2 to enhance the transcriptional activity of SlHsfA2. Thus, our results revealed a molecular mechanism that the SlWRKY55/SlVQ11-SlHsfA2 cascade enhanced thermotolerance and provided potential target genes for improving the adaptability of crops to HT.

3.
Small ; 20(27): e2310972, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38282180

RESUMEN

Recently, aqueous zinc-ion batteries with conversion mechanisms have received wide attention in energy storage systems on account of excellent specific capacity, high power density, and energy density. Unfortunately, some characteristics of cathode material, zinc anode, and electrolyte still limit the development of aqueous zinc-ion batteries possessing conversion mechanism. Consequently, this paper provides a detailed summary of the development for numerous aqueous zinc-based batteries: zinc-sulfur (Zn-S) batteries, zinc-selenium (Zn-Se) batteries, zinc-tellurium (Zn-Te) batteries, zinc-iodine (Zn-I2) batteries, and zinc-bromine (Zn-Br2) batteries. Meanwhile, the reaction conversion mechanism of zinc-based batteries with conversion mechanism and the research progress in the investigation of composite cathode, zinc anode materials, and selection of electrolytes are systematically introduced. Finally, this review comprehensively describes the prospects and outlook of aqueous zinc-ion batteries with conversion mechanism, aiming to promote the rapid development of aqueous zinc-based batteries.

4.
Phys Chem Chem Phys ; 26(38): 24735-24752, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39291319

RESUMEN

Since the proposal of the concept of semi-solid flow batteries (SSFBs), SSFBs have gained increased attention as an alternative for large-scale energy storage applications. As a new type of high energy density flow battery system, lithium-ion semi-solid flow batteries (Li-SSFBs) combine the features of both flow batteries and lithium-ion batteries and show the advantages of decoupling power and capacity. Moreover, Li-SSFBs typically can achieve much higher energy density while maintaining a lower cost. Therefore, Li-SSFBs are some of the most promising technologies for future energy storage. Despite these advantages, a significant gap towards the commercialization of Li-SSFBs still exists. In this article, we have reviewed the research progress of Li-SSFBs in aqueous and non-aqueous systems in recent years. We have further discussed the future research trends and application prospects of Li-SSFBs, providing guidelines for future research in this area.

5.
Artículo en Inglés | MEDLINE | ID: mdl-39210826

RESUMEN

The subcellular localization of RNA is critical to a variety of physiological and pathological processes. Dissecting the spatiotemporal regulation of the transcriptome is key to understanding cell function and fate. However, it remains challenging to effectively enrich and catalogue RNAs from various subcellular structures using traditional approaches. In recent years, proximity labeling has emerged as an alternative strategy for efficient isolation and purification of RNA from these intricate subcellular compartments. This review focuses on examining RNA-related proximity labeling tools and exploring their application in elucidating the spatiotemporal regulation of RNA at the subcellular level.

6.
Small ; 19(50): e2304504, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37635108

RESUMEN

Aqueous zinc-ion batteries (AZIBs) are considered to be one of the most promising devices for large-scale energy storage systems owing to their high theoretical capacity, environmental friendliness, and safety. However, the ionic intercalation or surface redox mechanisms in conventional cathode materials generally result in unsatisfactory capacities. Conversion-type aqueous zinc-tellurium (Zn-Te) batteries have recently gained widespread attention owing to their high theoretical specific capacities. However, it remains an enormous challenge to improve the slow kinetics of the aqueous Zn-Te batteries. Here, MoO2 nanoclusters embedded in hierarchical nitrogen-doped carbon nanoflower (MoO2 /NC) hosts are successfully synthesized and loaded with Te in aqueous Zn-Te batteries. Benefitting from the highly dispersed MoO2 nanoclusters and hierarchical nanoflower structure with a large specific surface area, the electrochemical kinetics of the Te redox reaction are significantly improved. As a result, the Te-MoO2 /NC electrode exhibits superior cycling stability and a high specific capacity of 493 mAh g-1 at 0.1 A g-1 . Meanwhile, the conversion mechanism is systematically explored using a variety of ex situ characterization methods. Therefore, this study provides a novel approach for enhancing the kinetics of the Te redox reaction in aqueous Zn-Te batteries.

7.
Opt Express ; 31(13): 21689-21705, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37381260

RESUMEN

Indirect imaging correlography (IIC) is a coherent imaging technique that provides access to the autocorrelation of the albedo of objects obscured from line-of-sight. This technique is used to recover sub-mm resolution images of obscured objects at large standoffs in non-line-of-sight (NLOS) imaging. However, predicting the exact resolving power of IIC in any given NLOS scene is complicated by the interplay between several factors, including object position and pose. This work puts forth a mathematical model for the imaging operator in IIC to accurately predict the images of objects in NLOS imaging scenes. Using the imaging operator, expressions for the spatial resolution as a function of scene parameters such as object position and pose are derived and validated experimentally. In addition, a self-supervised deep neural network framework to reconstruct images of objects from their autocorrelation is proposed. Using this framework, objects with ≈ 250 µ m features, located at 1 mt standoffs in an NLOS scene, are successfully reconstructed.

8.
BMC Neurosci ; 23(1): 62, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357867

RESUMEN

Inflammation and glutamate (GLU) are widely thought to participate in the pathogenesis of depression, and current evidence suggests that the development of depression is associated with the activation of the kynurenine pathway (KP). However, the exact mechanism of KP among the inflammation, GLU and depression remain poorly understood. In this study, we examined the involvement of KP, inflammation and GLU in depressive phenotype induced by chronic unpredictable mild stress (CUMS) in C57B/6 J mice. Our results showed that CUMS caused depressive like-behavior in the sucrose preference test, tail suspension test and forced swimming test. From a molecular perspective, CUMS upregulated the peripheral and central inflammatory response and activated indoleamine 2,3-dioxygenase (IDO), the rate-limiting enzyme of KP, which converts tryptophan (TRP) into kynurenine (KYN). KYN is a precursor for QA in microglia, which could activate the N-methyl-D-aspartate receptor (NMDAR), increasing the GLU release, mirrored by increased IDO activity, quinolinic acid and GLU levels in the hippocampus, prefrontal cortex and serum. However, intervention with IDO inhibitor 1-methyl-DL-tryptophan (50 mg/kg/s.c.) and 1-methyl-L-tryptophan (15 mg/kg/i.p.) reversed the depressive-like behaviors and adjusted central and peripheral KP's metabolisms levels as well as GLU content, but the inflammation levels were not completely affected. These results provide certain evidence that KP may be a vital pathway mediated by IDO linking inflammation and glutamate, contributing to depression.


Asunto(s)
Depresión , Quinurenina , Ratones , Animales , Quinurenina/metabolismo , Depresión/etiología , Depresión/metabolismo , Triptófano , Ácido Glutámico/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Modelos Animales de Enfermedad , Inflamación
9.
Macromol Rapid Commun ; 43(16): e2200079, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35267224

RESUMEN

In contrast to small-molecule multiple resonance emitters processed via vacuum evaporation technology, the design of multiple resonance dendrimers is presented by introducing the first- and second-generation carbazole dendrons in the periphery of boron, oxygen, nitrogen-doped polycyclic aromatic skeleton, for efficient narrowband blue electroluminescence by a solution process. The multiple resonance dendrimers not only keep the narrowband emission of the polycyclic aromatic skeleton, but also can suppress their intermolecular aggregation by steric carbazole dendrons, overcoming the unwanted spectral broadening in the solid state. The resultant first-generation carbazole dendrimer exhibits narrowband blue emission with promising photoluminescent quantum efficiency of 94% and delayed fluorescence with a lifetime of 139.1 µs in the solid-state film. Solution-processed organic light-emitting diodes based on the dendrimers reveal electroluminescence at 488 nm with full-width at half maximum of 39 nm, the maximum luminous efficiency of 29.2 cd A-1 , and maximum external quantum efficiency of 13.4%.

10.
Pacing Clin Electrophysiol ; 45(7): 826-831, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35357704

RESUMEN

INTRODUCTION: Transseptal puncture (TSP) is routinely performed for left heart intervention, but it can sometimes be complex and life-threatening. This study introduced a safe and effective method to facilitate TSP for left atrial access. METHODS AND RESULTS: A total of 200 patients (190 with atrial fibrillation, 10 with a left accessory pathway) were prospectively analyzed. In the guidewire group, TSP was performed using a SWARTZ sheath and a Brockenbrough needle with a 0.014-inch coronary guidewire instead of an inner stylet. The needle tip position was confirmed by pushing the guidewire into the left superior pulmonary vein after initial puncture in 100 patients. In the contrast group, TSP was performed in 100 patients using standard devices by injecting contrast to confirm needle-tip position. Left atrial access was achieved successfully in all patients in the two groups without serious complications. The guidewire group showed a higher first-pass rate for left atrial access compared with the contrast group (81.1% vs. 75% p < .001, respectively). CONCLUSION: Coronary guidewire TSP is safe and is associated with a high success rate, and it is thus a useful alternative to conventional TSP. This method is useful for patients with septal aneurysms and contrast allergies.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Fibrilación Atrial/cirugía , Ablación por Catéter/métodos , Atrios Cardíacos/cirugía , Humanos , Punciones/métodos , Resultado del Tratamiento
11.
Immunology ; 163(3): 278-292, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33513265

RESUMEN

Interferon regulatory factor 3 (IRF3) is a critical transcription factor for inducing production of type I interferons (IFN-I) and regulating host antiviral response. Although IRF3 activation during viral infection has been extensively studied, the inhibitory regulation of IRF3 remains largely unexplored. Here, we revealed that Midline-1 (MID1) is a ubiquitin E3 ligase of IRF3 that plays essential roles in regulating the production of IFN-I. We found that MID1 physically interacts with IRF3 and downregulates IRF3 protein levels. Next, we demonstrated that MID1 can induce K48-linked polyubiquitination of IRF3, thus lowing the protein stability of IRF3. Our further studies identified Lys313 as a major ubiquitin acceptor lysine of IRF3 induced by MID1. Finally, MID1-mediated ubiquitination and degradation of IRF3 restrict IFN-I production and cellular antiviral response. This study uncovers a role of MID1 in regulating innate antiviral immunity and may provide a potential target for enhancing host antiviral activity.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/fisiología , Gripe Humana/inmunología , Infecciones por Orthomyxoviridae/inmunología , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Sistemas CRISPR-Cas , Células HEK293 , Humanos , Inmunidad Innata , Factor 3 Regulador del Interferón/genética , Factor 3 Regulador del Interferón/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteolisis , ARN Interferente Pequeño/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
12.
Small ; 17(45): e2104144, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34605170

RESUMEN

Perovskite-based oxides attract great attention as catalysts for energy and environmental devices. Nanostructure engineering is demonstrated as an effective approach for improving the catalytic activity of the materials. The mechanism for the enhancement, nevertheless, is still not fully understood. In this study, it is demonstrated that compressive strain can be introduced into freestanding perovskite cobaltite La0.8 Sr0.2 CoO3- δ (LSC) nanofibers with sufficient small size. Crystal structure analysis suggests that the LSC fiber is characterized by compressive strain along the ab plane and less distorted CoO6 octahedron compared to the bulk powder sample. Accompanied by such structural changes, the nanofiber shows significantly higher oxygen reduction reaction (ORR) activity and better stability at elevated temperature, which is attributed to the higher oxygen vacancy concentration and suppressed Sr segregation in the LSC nanofibers. First-principle calculations further suggest that the compressive strain in LSC nanofibers effectively shortens the distance between the Co 3d and O 2p band center and lowers the oxygen vacancy formation energy. The results clarify the critical role of surface stress in determining the intrinsic activity of perovskite oxide nanomaterials. The results of this work can help guide the design of highly active and durable perovskite catalysts via nanostructure engineering.

13.
Int J Mol Sci ; 22(24)2021 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-34948071

RESUMEN

Basic helix-loop-helix proteins (bHLHs) play very important roles in the anthocyanin biosynthesis of many plant species. However, the reports on blueberry anthocyanin biosynthesis-related bHLHs were very limited. In this study, six anthocyanin biosynthesis-related bHLHs were identified from blueberry genome data through homologous protein sequence alignment. Among these blueberry bHLHs, VcAN1, VcbHLH42-1, VcbHLH42-2 and VcbHLH42-3 were clustered into one group, while VcbHLH1-1 and VcbHLH1-2 were clustered into the other group. All these bHLHs were of the bHLH-MYC_N domain, had DNA binding sites and reported conserved amino acids in the bHLH domain, indicating that they were all G-box binding proteins. Protein subcellular location prediction result revealed that all these bHLHs were nucleus-located. Gene structure analysis showed that VcAN1 gDNA contained eight introns, while all the others contained seven introns. Many light-, phytohormone-, stress- and plant growth and development-related cis-acting elements and transcription factor binding sites (TFBSs) were identified in their promoters, but the types and numbers of cis-elements and TFBSs varied greatly between the two bHLH groups. Quantitative real-time PCR results showed that VcAN1 expressed highly in old leaf, stem and blue fruit, and its expression increased as the blueberry fruit ripened. Its expression in purple podetium and old leaf was respectively significantly higher than in green podetium and young leaf, indicating that VcAN1 plays roles in anthocyanin biosynthesis regulation not only in fruit but also in podetium and leaf. VcbHLH1-1 expressed the highest in young leaf and stem, and the lowest in green fruit. The expression of VcbHLH1-1 also increased as the fruit ripened, and its expression in blue fruit was significantly higher than in green fruit. VcbHLH1-2 showed high expression in stem but low expression in fruit, especially in red fruit. Our study indicated that the anthocyanin biosynthesis regulatory functions of these bHLHs showed certain spatiotemporal specificity. Additionally, VcAN1 might be a key gene controlling the anthocyanin biosynthesis in blueberry, whose function is worth exploring further for its potential applications in plant high anthocyanin breeding.


Asunto(s)
Antocianinas/biosíntesis , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Arándanos Azules (Planta)/metabolismo , Arándanos Azules (Planta)/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética
14.
Heart Surg Forum ; 23(5): E685-E688, 2020 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-32990566

RESUMEN

A 71-year-old man presented to us with recurrent chest pain, which led to cardiac catheterization. He was a strong candidate for redo coronary artery bypass grafting (CABG). CT was performed to confirm whether the heart was adherent to the sternum and chest wall. For safety reasons, cardiopulmonary bypass (CPB) was first performed via right femoral cannulation before sternotomy. After the spontaneous right ventricular (RV) rupture, HTK was used to arrest the heart. Heart repair materials were applied to repair the fissure of RV to avoid further tearing and bleeding. A compromise scheme was adopted when it was found to be difficult to identify and expose well the target artery, due to severe adhesion. This was done to avoid possible severe consequences of further dissection of the heart. Intraoperative transesophageal echocardiography (TEE) was used to evaluate the cardiac function, and intra-aortic balloon pump (IABP) support was applied in time. In consideration of the RV enlargement, which TEE revealed may have been caused by myocardial edema and cardiac insufficiency, modified ultrafiltration was performed, and a timely decision of open chest management (OCM) with delayed sternal closure (DSC) was made to maintain hemodynamic stability. The patient had no further complications and eventually recovered well, according to a 4-month follow up.


Asunto(s)
Puente de Arteria Coronaria/efectos adversos , Enfermedad de la Arteria Coronaria/cirugía , Rotura Cardíaca/etiología , Complicaciones Posoperatorias , Anciano , Cateterismo Cardíaco , Ecocardiografía Transesofágica , Rotura Cardíaca/diagnóstico , Ventrículos Cardíacos , Humanos , Imagenología Tridimensional , Masculino , Tomografía Computarizada por Rayos X
15.
Int J Mol Sci ; 21(9)2020 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-32349372

RESUMEN

Introns exist not only in coding sequences (CDSs) but also in untranslated regions (UTRs) of a gene. Recent studies in animals and model plants such as Arabidopsis have revealed that the UTR-introns (UIs) are widely presented in most genomes and involved in regulation of gene expression or RNA stability. In the present study, we identified introns at both 5'UTRs (5UIs) and 3'UTRs (3UIs) of sweet orange genes, investigated their size and nucleotide distribution characteristics, and explored the distribution of cis-elements in the UI sequences. Functional category of genes with predicted UIs were further analyzed using GO, KEGG, and PageMan enrichment. In addition, the organ-dependent splicing and abundance of selected UI-containing genes in root, leaf, and stem were experimentally determined. Totally, we identified 825 UI- and 570 3UI-containing transcripts, corresponding to 617 and 469 genes, respectively. Among them, 74 genes contain both 5UI and 3UI. Nucleotide distribution analysis showed that 5UI distribution is biased at both ends of 5'UTR whiles 3UI distribution is biased close to the start site of 3'UTR. Cis- elements analysis revealed that 5UI and 3UI sequences were rich of promoter-enhancing related elements, indicating that they might function in regulating the expression through them. Function enrichment analysis revealed that genes containing 5UI are significantly enriched in the RNA transport pathway. While, genes containing 3UI are significantly enriched in splicesome. Notably, many pentatricopeptide repeat-containing protein genes and the disease resistance genes were identified to be 3UI-containing. RT-PCR result confirmed the existence of UIs in the eight selected gene transcripts whereas alternative splicing events were found in some of them. Meanwhile, qRT-PCR result showed that UIs were differentially expressed among organs, and significant correlation was found between some genes and their UIs, for example: The expression of VPS28 and its 3UI was significantly negative correlated. This is the first report about the UIs in sweet orange from genome-wide level, which could provide evidence for further understanding of the role of UIs in gene expression regulation.


Asunto(s)
Citrus sinensis/genética , Genoma de Planta , Estudio de Asociación del Genoma Completo , Intrones , Regiones no Traducidas , Regiones no Traducidas 3' , Regiones no Traducidas 5' , Empalme Alternativo , Mapeo Cromosómico , Estudio de Asociación del Genoma Completo/métodos , Genómica/métodos , Sistemas de Lectura Abierta , Sitios de Empalme de ARN , Secuencias Reguladoras de Ácidos Nucleicos
16.
J Med Ultrasound ; 26(2): 85-89, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30065525

RESUMEN

OBJECTIVE: High-resolution ultrasonography (HRUS) has been used recently to characterize median and ulnar nerves but is seldom used to characterize the lower extremity nerves. The reference standard for normal the lower extremity nerves has not been established. Thus, this study measured the cross-sectional areas (CSAs) of the sciatic nerve of 200 healthy male or female volunteers, aged 18-80 using HRUS. These data provide basic clinical data for the use of high-resolution ultrasound for the future diagnosis, treatment, and prognostic evaluation of peripheral neuropathies. METHODS: Two hundred healthy volunteers with 400 lower extremities were studied with HRUS. According to their age, the subjects were assigned to young group (18-30 years, n = 75), middle group. (31-60 years, n = 70), and old group(61-80 year, n = 55). Age, sex, height, weight were recorded and CSAs of sciatic nerve were obtained at every predetermined sites. RESULTS: The mean CSAs of sciatic nerves at GS and MGPF were 0.527 ± 0.028 cm2 and 0.444 ± 0.026 cm2 respectively. Pearson's correlation analysis showed that the mean CSAs were correlated with height and weight. There was no difference in mean CSAs among the three groups (P > 0.05). Women had smaller CSAs of the normal Sciatic nerves than men in two measuring sites (GS, MGPF) (P < 0.05). CONCLUSION: Peripheral nerve ultrasonography is a reliable and reproducible diagnostic method in the hands of experienced examiners. Normal values for the sciatic nerve nerves are provided by our study. Thus, reference values of Sciatic nerve CSA of the lower extremity can facilitate the analysis of abnormal nerve conditions.

17.
Phys Chem Chem Phys ; 19(38): 26310-26321, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28936526

RESUMEN

In this article, we develop a new finite-element-based model for the simulation of the electrochemical impedance spectroscopy (EIS) response of mixed ionic electronic conducting (MIEC) thin films. We first validated the model against experimental data for Sm-doped CeO2 (SDC) symmetrical films deposited on an yittria-stabilized ZrO2 (YSZ) substrate, a pure ionic conductor. We first studied the configuration where the patterned electrodes are placed on top of the MIEC ("exposed" configuration). Our model is capable of correctly reproducing the EIS response and the total capacitance, together with their dependence on the oxygen partial pressure. Furthermore, we were able to show, in agreement with experiments, that the area specific resistance (Rp) is relatively insensitive to the density of triple phase boundaries. As a second step, we studied the configuration where the metal current collector is directly deposited on the ionic conductor and is, therefore, "embedded" into the MIEC. We were again able to reproduce the experimental EIS response. We also discovered that at sufficiently high frequencies, the EIS deviates from a traditional RC-type response, leading to features attributable to the coupling ionic and electronic transport. This coupling ultimately adds to the area specific resistance. The latter, however, can be minimized if the film is sufficiently thick or if the current collector configuration is chosen judiciously.

19.
Nanotechnology ; 27(38): 385604, 2016 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-27528593

RESUMEN

Exfoliated molybdenum disulfide (MoS2) has unique 2H phase and semiconductor properties and potential applications across a wide range of fields. However, the chemically exfoliated MoS2 nanosheets from Li x MoS2 have a 1T phase, and searching for a fast route to get processable 2H-MoS2 nanosheets and its nanocomposites is still an urgent task. This study reports on a simple, fast and efficient microwave strategy to achieve the 1T to 2H phase conversion of MoS2 and the successful preparation of processable 2H-MoS2 nanosheets and their nanocomposites. The method here may be easily changed to achieve the phase change of other exfoliated TMDs.

20.
Front Immunol ; 15: 1369972, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38690285

RESUMEN

Background: Temozolomide (TMZ) is a key component in the treatment of gliomas. Hypermutation induced by TMZ can be encountered in routine clinical practice, and its significance is progressively gaining recognition. However, the relationship between TMZ-induced hypermutation and the immunologic response remains controversial. Case presentation: We present the case of a 38-year-old male patient who underwent five surgeries for glioma. Initially diagnosed with IDH-mutant astrocytoma (WHO grade 2) during the first two surgeries, the disease progressed to grade 4 in subsequent interventions. Prior to the fourth surgery, the patient received 3 cycles of standard TMZ chemotherapy and 9 cycles of dose-dense TMZ regimens. Genomic and immunologic analyses of the tumor tissue obtained during the fourth surgery revealed a relatively favorable immune microenvironment, as indicated by an immunophenoscore of 5, suggesting potential benefits from immunotherapy. Consequently, the patient underwent low-dose irradiation combined with immunoadjuvant treatment. After completing 4 cycles of immunotherapy, the tumor significantly shrank, resulting in a partial response. However, after a 6-month duration of response, the patient experienced disease progression. Subsequent analysis of the tumor tissue obtained during the fifth surgery revealed the occurrence of hypermutation, with mutation signature analysis attributing TMZ treatment as the primary cause. Unfortunately, the patient succumbed shortly thereafter, with a survival period of 126 months. Conclusion: Patients subjected to a prolonged regimen of TMZ treatment may exhibit heightened vulnerability to hypermutation. This hypermutation induced by TMZ holds the potential to function as an indicator associated with unfavorable response to immunotherapy in gliomas.


Asunto(s)
Antineoplásicos Alquilantes , Neoplasias Encefálicas , Glioma , Mutación , Temozolomida , Humanos , Temozolomida/uso terapéutico , Masculino , Adulto , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/inmunología , Glioma/genética , Glioma/terapia , Glioma/tratamiento farmacológico , Antineoplásicos Alquilantes/uso terapéutico , Inmunoterapia/métodos , Resultado Fatal , Microambiente Tumoral/inmunología
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