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1.
J Colloid Interface Sci ; 678(Pt C): 101-110, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39284248

RESUMEN

The hydrogen evolution reaction (HER) in water splitting is among the foremost methods to produce clean and green hydrogen from renewable sources. The practical use of the HER technology is however hindered by the high price and/or the relatively low efficiency of the currently used catalysts. Herein, we report a heterostructured W/W2C electrocatalyst featuring vertically stacked interfaces and embedded in N-doped porous graphitic carbon (denoted as W/W2C@N-PGC) as a high-performance electrocatalyst for the HER in a wide pH range. The catalyst synthesis, accomplished through a straightforward one-pot method, is both facile and highly efficient, involving freeze-drying a suspension of the starting materials followed by pyrolyzing the obtained dry gel. Density functional theory calculations revealed the crucial role of the W/W2C heterojunction in promoting the two key steps of the HER, viz. HOH bond scission and H2 emission. Electrochemical data confirmed the excellent electrocatalytic capability of W/W2C@N-PGC toward the HER process in a wide pH range including alkaline, acidic, and neutral electrolytes. In 1.0 M KOH, we measured a low overpotential of 102 mV to drive a current density of 10 mA cm-2; a long-term stability (up to 24 h) was also realized. The data presented in this work highlight the importance of electrocatalysts with heterojunctions for the HER and the methodology presented in this work may be extended to other contemporary energy-related technologies such as CO2 reduction, oxygen evolution, and oxygen reduction reactions.

2.
Small ; : e2405921, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39279613

RESUMEN

Hard carbon (HC) stands out as the most prospective anode for sodium-ion batteries (SIBs) with significant potential for commercial applications. However, some long-standing and intractable obstacles, like low first coulombic efficiency (ICE), poor rate capability, storage capacity, and cycling stability, have severely hindered the conversion process from laboratory to commercialization. The above-mentioned issues are closely related to Na+ transfer kinetics, surface chemistry, and internal pseudo-graphitic carbon content. Herein, constructing molybdenum-modified hard carbon solid spheres (Mo2C/HC-5.0), both the ion transfer kinetics, surface chemistry, and internal pseudo-graphitic carbon content are comprehensively improved. Specifically, Mo2C/HC-5.0 with higher pseudo-graphitic carbon content provides a large number of active sites and a more stable layer structure, resulting in improved sodium storage capacity, rate performance, and cycling stability. Moreover, the lower defect density and specific surface area of Mo2C/HC-5.0 further enhance ICE and sodium storage capacity. Consequently, the Mo2C/HC-5.0 anode achieves a high capacity of 410.7 mA h g-1 and an ICE of 83.9% at 50 mA g-1. Furthermore, the material exhibits exceptional rate capability and cycling stability, maintaining a capacity of 202.8 mA h g-1 at 2 A g-1 and 214.9 mA h g-1 after 800 cycles at 1 A g-1.

3.
J Acoust Soc Am ; 156(3): 1575-1585, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39248556

RESUMEN

The low-order normal modes with small grazing angles (SGA) often control long-range sound field characteristics in shallow water. The SGA reflection loss from a half-space low-velocity bottom (LVB) is independent of the sound attenuation, except around the angle of complete transmission; the SGA bottom reflection loss (BRL) from a seafloor with a top low-velocity layer is very insensitive to the LVB attenuation also, except around a few selected frequencies. Thus, the "seafloor velocity-attenuation coupling" problem will be more fatal for LVB geo-acoustic inversions. The dispersion equation of the normal modes in the LVB layer is coincidentally the same as the singularity expression of the SGA reflection coefficient in the water column, resulting in a sound siphon effect that causes the abnormally high SGA BRL and transmission loss in the water at the siphon frequencies. The siphon effect is very sensitive to seafloor acoustic parameters, might offer a physical base for geo-acoustic inversion, and show a dim light in a "gray area" for inverting the LVB sound attenuation at low to mid frequencies. As an example, the acoustic siphon effect and related seafloor geophysical parameters forming it in the Yellow Sea are reported in this paper.

4.
Nano Lett ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39265052

RESUMEN

Surface plasmon polaritons from plasmonic nanocavity have aroused great interest due to their applications in various fields, in which on-demand design is hindered by the lack of theoretical frameworks. Herein, based on its wave nature, we developed a wavefunction theory to explicitly describe individual surface plasmon polaritons and the resultant near-field and far-field behaviors, which serves as an efficient platform for high-throughput on-demand design of nanocavities. We found an applicative wavefunction form and proposed a two-body interaction function and a "shell" model for many-body interactions in surface plasmon polaritons' coupling. The wavefunction of individual surface plasmon polaritons and resultant near-field and far-field behaviors can be given explicitly and precisely. The theory provides a fundamental and quantitative understanding of surface plasmon polaritons and enables highly efficient on-demand design of plasmonic metamaterials and devices, leading to further methodological applications in numerous aspects.

5.
Int J Chron Obstruct Pulmon Dis ; 19: 1957-1969, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39247666

RESUMEN

Background: The associations between gut microbiota and chronic obstructive pulmonary disease (COPD) have gained increasing attention and research interest among scholars. However, it remains unclear whether gut microbiota serves as a causal factor for COPD or if it is a consequence of the disease. Therefore, we investigated the causal relationship between COPD and gut microbiota, with intention of providing novel insights and references for clinical diagnosis and treatment. Methods: Based on the genome-wide association study (GWAS) data, we employed MR-Egger regression, random-effects inverse variance-weighted (IVW) method, and weighted median method for bidirectional Mendelian randomization (MR) analysis. We conducted Cochran's Q test for heterogeneity assessment and performed multivariable analysis, sensitivity analysis, and heterogeneity testing to validate the reliability and stability of results. Results: Utilizing MR analysis, mainly employing the IVW method, we detected a collective of 11 gut microbiota species that exhibited associations with COPD. Among them, Bacteroidia, family XIII, Clostridium innocuum group, Barnesiella, Collinsella, Lachnospiraceae NK4A136 group, Lachnospiraceae UCG004, Lachnospiraceae UCG010, and Bacteroidales were found to be protective factors for COPD. On the other hand, Holdemanella and Marvinbryantia were identified as risk factors for COPD. Individuals with elevated levels of Holdemanella exhibited a 1.141-fold higher risk of developing COPD compared to their healthy counterparts, and those with increased levels of Marvinbryantia had a 1.154-fold higher risk. Reverse MR analysis yielded no evidence indicating a causal relationship between gut microbiota and COPD occurrence. Conclusion: Our study established a causal link between 11 specific gut microbiota species and COPD, offering novel insights and valuable references for targeted therapies in the clinical management of COPD. However, our results were mainly based on the analysis of database, and further clinical studies are needed to clarify the effects of gut microbiota on COPD and its specific protective mechanism.


Asunto(s)
Microbioma Gastrointestinal , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Enfermedad Pulmonar Obstructiva Crónica , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/genética , Humanos , Factores de Riesgo , Disbiosis , Medición de Riesgo , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/clasificación , Predisposición Genética a la Enfermedad , Fenotipo , Pulmón/microbiología , Pulmón/fisiopatología , Factores Protectores
6.
Small ; : e2405453, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39263778

RESUMEN

High-quality solid electrolyte interphase (SEI) layers can effectively suppress the growth of Li dendrites and improve the cycling stability of lithium metal batteries. Herein, 1-(6-bromohexanoyl)-3-butylurea is used to construct an organic/inorganic hybrid (designated as LiBr-HBU) SEI layer that features a uniform and compact structure. The LiBr-HBU SEI layer exhibits superior electrolyte wettability and air stability as well as strong attachment to Li foils. The LiBr-HBU SEI layer achieves a Li+ conductivity of 2.75 × 10-4 S cm-1, which is ≈50-fold higher than the value measured for a native SEI layer. A Li//Li symmetric cell containing the LiBr-HBU SEI layer exhibits markedly improved cyclability when compared with the cell containing a native SEI layer, especially at a high current density (e.g., cycling life up to 1333 h at 15 mA cm-2). The LiBr-HBU SEI layer also improves the performance of lithium-sulfur cells, particularly the rate capability (548 mAh g-1 at 10 C) and cycling stability (513 mAh g-1 at 0.5 C after 500 cycles). The methodology described can be extended to the commercial processing of Li metal anodes as the artificial SEI layer also protects Li metal against corrosion.

7.
Heliyon ; 10(15): e35467, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39165987

RESUMEN

Background: Lipid accumulation and redox imbalance, resulting from dysregulation of hepatic fatty acids oxidation, contribute to the development of steatohepatitis and insulin resistance. Recently, dysregulated RNA N6-methyladenosine (m6A) methylation modification has been found involving fatty liver. However, the role of methyltransferase-like 14 (METTL14), the core component of m6A methylation, in the development of steatohepatitis is unknown. Herein, we aimed to explore the role of METTL14 on steatohepatitis and insulin resistance in mice with metabolic dysfunction-associated steatotic liver disease (MASLD). Methods: The liver tissues of mice and patients with MASLD were collected to detect the expression of METTL14. METTL14 overexpression and METTL14 silence were used to investigate the effect of METTL14 on lipid metabolism disorder in vivo and in vitro. Knockout of METTL14 in primary hepatocytes was used to investigate the role of Sirtuin 1 (SIRT1) on lipid accumulation induced by METTL14. Results: METTL14 was dramatically up-regulated in the livers of db/db mice, high-fat diet (HFD)-fed mice, and patients with MASLD. METTL14 overexpression exacerbated MASLD and promoted lipid metabolism disorder and insulin resistance in mice. Conversely, METTL14 knockout ameliorated lipid deposition and insulin resistance in HFD-fed mice. Furthermore, METTL14 overexpression facilitated lipid accumulation, while METTL14 knockout reduced lipid accumulation in HepG2 cells and primary hepatocytes. In addition, METTL14 lost up-regulated SIRT1 expression in hepatocytes. SIRT1 deficiency abrogated the ameliorating effects of METTL14 downregulation in MASLD mice. Conclusions: These findings suggest that dysfunction of the METTL14-SIRT1 pathway might promote hepatic steatosis and insulin resistance.

9.
Bioresour Technol ; 408: 131195, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39098358

RESUMEN

Anammox is recognized as a prospective alternative for future biological nitrogen removal technologies. However, the nitrate by-products produced by anammox bacteria limit its overall nitrogen removal efficiency below 88 %. This study introduced Fe(III) into the anammox bioreactor to enhance the nitrogen removal efficiency to approximately 95 %, surpassing the biochemical limit of 88 % imposed by anammox stoichiometry. Anammox sludge was demonstrated to utilize extracellular polymeric substances to reduce Fe(III) into Fe(II), and this process promoted the dominance of Ca. Brocadia. The iron addition improved the abundance of narGHI genes and facilitated the partial dissimilatory nitrate reduction to ammonium, with nitrite as the end product. The accumulated nitrite was then eliminated through the anammox pathway, along with the excess ammonium (30 mg/L) in the influent. Overall, this study deepens our understanding of the enhanced nitrogen removal triggered by Fe(III) in anammox sludge and offers an effective approach to boost anammox process.


Asunto(s)
Reactores Biológicos , Nitratos , Nitrógeno , Oxidación-Reducción , Aguas del Alcantarillado , Nitrógeno/metabolismo , Nitratos/metabolismo , Aguas del Alcantarillado/microbiología , Compuestos de Amonio/metabolismo , Compuestos Férricos/metabolismo , Anaerobiosis , Hierro/metabolismo , Bacterias/metabolismo
10.
Pediatr Neurol ; 160: 26-29, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39178650

RESUMEN

BACKGROUND: Anti-Purkinje cell cytoplasmic antibody type 2 (PCA-2) is associated with various neurological conditions in adults. However, related studies have not been conducted in children. The present study aimed to characterize the clinical features and outcomes of PCA-2-related autoimmune cerebellar degeneration in pediatric patients. METHODS: A total of 357 pediatric patients with acute or subacute cerebellar ataxia were recruited for the study from June 2015 to September 2022. Of these, PCA-2 was identified in four patients. Information on the clinical manifestations, patient response to treatment, and outcomes was collected and analyzed. RESULTS: The patient cohort in the present study included two boys and two girls, with the age of onset from six to 12 years. Axial ataxia was the most remarkable symptom observed in the entire patient cohort (four of four), followed by dysmetria in 75% (three of four), dysarthria in 50% (two of four), and nystagmus in 25% (one of four) of patients. Cognitive impairment was present in one patient. Peripheral neuropathy, which is an extracerebellar symptom, was found in two patients. One patient was diagnosed with a pelvic neuroblastoma before the onset of ataxia. The presence of oligoclonal bands was confirmed in the cerebrospinal fluid, and cerebellar atrophy was observed. Immunotherapy, including glucocorticoids and/or intravenous immunoglobulin, was administered to all four patients immediately following diagnosis, and mycophenolate mofetil was administered to three patients. Three patients responded to immunotherapy. CONCLUSIONS: In children, PCA2-associated autoimmune cerebellar degeneration is rare, and they show comparatively fewer symptoms than adults. Timely and appropriate immunotherapy is beneficial.


Asunto(s)
Autoanticuerpos , Humanos , Masculino , Femenino , Niño , Autoanticuerpos/líquido cefalorraquídeo , Autoanticuerpos/sangre , Células de Purkinje/patología , Células de Purkinje/inmunología , Fenotipo , Ataxia Cerebelosa/inmunología , Ataxia Cerebelosa/fisiopatología
11.
Diabetes Res Clin Pract ; 216: 111822, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39154657

RESUMEN

AIMS: This study endeavors to explore the ramifications of early dynamic blood glucose (BG) trajectories within the initial 48 h of intensive care unit (ICU) admission on mortality among critically ill heart failure (HF) patients. METHODS: The study employed a retrospective observational design, analyzing dynamic BG data of HF patients from the Medical Information Mart for Intensive Care IV database. The BG trajectory subphenotypes were identified using the hierarchical clustering based on the dynamic time-warping algorithm. The primary outcome of the study was 28-day mortality, with secondary outcomes including 180-day and 1-year mortality. RESULTS: We screened a total of 21,098 HF patients and finally 15,092 patients were included in the study. Our results identified three distinct BG trajectory subphenotypes: increasing (n = 3503), stabilizing (n = 6250), and decreasing (n = 5339). The increasing subphenotype was associated with the highest mortality risk at 28 days, 180 days, and 1 year. The stabilizing and decreasing subphenotypes showed significantly lower mortality risks across all time points, with hazard ratios ranging from 0.85 to 0.88 (P<0.05 for all). Sensitivity analyses confirmed the robustness of these findings after adjusting for various covariates. CONCLUSIONS: Increasing BG trajectory within 48 h of admission is significantly associated with higher mortality in patients with HF. It is necessary to devote greater attention to the early BG dynamic changes in HF patients to optimize clinical BG management and enhance patient prognosis.


Asunto(s)
Glucemia , Enfermedad Crítica , Insuficiencia Cardíaca , Humanos , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/sangre , Enfermedad Crítica/mortalidad , Masculino , Femenino , Estudios Retrospectivos , Anciano , Glucemia/análisis , Glucemia/metabolismo , Persona de Mediana Edad , Unidades de Cuidados Intensivos/estadística & datos numéricos , Pronóstico
12.
Light Sci Appl ; 13(1): 146, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38951490

RESUMEN

Terahertz (THz) emission spectroscopy (TES) has emerged as a highly effective and versatile technique for investigating the photoelectric properties of diverse materials and nonlinear physical processes in the past few decades. Concurrently, research on two-dimensional (2D) materials has experienced substantial growth due to their atomically thin structures, exceptional mechanical and optoelectronic properties, and the potential for applications in flexible electronics, sensing, and nanoelectronics. Specifically, these materials offer advantages such as tunable bandgap, high carrier mobility, wideband optical absorption, and relatively short carrier lifetime. By applying TES to investigate the 2D materials, their interfaces and heterostructures, rich information about the interplay among photons, charges, phonons and spins can be unfolded, which provides fundamental understanding for future applications. Thus it is timely to review the nonlinear processes underlying THz emission in 2D materials including optical rectification, photon-drag, high-order harmonic generation and spin-to-charge conversion, showcasing the rich diversity of the TES employed to unravel the complex nature of these materials. Typical applications based on THz emissions, such as THz lasers, ultrafast imaging and biosensors, are also discussed. Step further, we analyzed the unique advantages of spintronic terahertz emitters and the future technological advancements in the development of new THz generation mechanisms leading to advanced THz sources characterized by wide bandwidth, high power and integration, suitable for industrial and commercial applications. The continuous advancement and integration of TES with the study of 2D materials and heterostructures promise to revolutionize research in different areas, including basic materials physics, novel optoelectronic devices, and chips for post-Moore's era.

13.
Sci Total Environ ; 949: 174928, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39079637

RESUMEN

Surface urban heat island (SUHI) intensity generally determined by satellite-derived clear-sky land surface temperature (LST) has ignored the impacts of cloud coverage and cannot reflect the real SUHI intensity. Only a few studies focus on the effects of this issue based on short-time LST datasets, which could contain non-negligible uncertainties to summarize reliable rules. To investigate the influence, the SUHI intensity (SUHII) clear-sky bias (CSB), which is defined as the SUHII difference between clear-sky and all-weather conditions, was investigated in 35 cities in China, based on clear-sky and all-weather LST datasets from 2003 to 2022. Results show that the two SUHIIs show similar spatial distribution patterns, with stronger SUHIs in southern China at daytime and weaker at nighttime. However, a non-negligible difference can be found between these two SUHIIs, with a SUHII CSB range of -1.43 to 2.27 °C at daytime and - 2.17 to 0.91 °C at nighttime. In terms of intra-annual variation, SUHII CSBs in similar climate regions exhibit similar patterns but different ranges due to their different natural properties. Generally, intra-annual variations of SUHII CSB can be divided into three groups, i.e., "Table Mountain", single peak, and single valley, varying across climate regions and years. The main reason for SUHII CSB was analyzed, i.e., spatial gaps of the data directly caused the SUHII CSB, and the thermal properties and meteorological conditions of the missing pixels affect the magnitude of the SUHII CSB. Taking the urban system as an example, this study has provided evidence of the non-negligible SUHII clear-sky bias to emphasize the importance of using all-weather LST for relevant studies.

14.
Food Funct ; 15(16): 8544-8561, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39072440

RESUMEN

Low selenium levels are closely associated with reduced cognitive performance and lipid dysregulation, yet the mechanism of action remains unclear. The physiological function of selenium is primarily mediated by selenoproteins. Selenoprotein H (SELENOH), as one of the selenium-containing proteins, has an unelucidated role in regulating cognitive status and lipid metabolism. In this study, we established a Selenoh gene knockout (HKO) mouse model to investigate whether Selenoh mediates the impact of selenium on cognitive function. We found that HKO mice showed a significant decline in cognition compared with the wild-type (HWT) littermates, and were not affected by deficient or excessive selenium, while no differences in anxiety and depression behavior were observed. HKO mice showed reduced myelin basic protein expression in hippocampal oligodendrocytes, with decreased glycolipid levels and increased phospholipid and sphingolipid levels in the hippocampus. Furthermore, the high-fat diet (HFD) exerted no effect on cognition and limited impact on the gene profile in the hippocampus of HKO mice. Compared with those of HWT mice, the myelination pathways in the hippocampus of HKO mice were downregulated as revealed by RNA-seq, which was further confirmed by the reduced expression levels of myelin-related proteins. Finally, HKO increased the expression of hippocampal fatty acid transporter (FATP) 4, and HFD increased the FATP4 expression in HWT mice but not in HKO mice. In summary, our study demonstrated that HKO induced cognitive decline by impairing myelination in oligodendrocytes with disrupted hippocampal lipid metabolism, which provided a novel viewpoint on the selenoprotein-mediated neurodegenerative diseases of selenium.


Asunto(s)
Disfunción Cognitiva , Hipocampo , Metabolismo de los Lípidos , Ratones Noqueados , Oligodendroglía , Selenio , Animales , Oligodendroglía/metabolismo , Hipocampo/metabolismo , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/genética , Ratones , Femenino , Selenio/metabolismo , Vaina de Mielina/metabolismo , Ratones Endogámicos C57BL , Selenoproteínas/metabolismo , Selenoproteínas/genética
15.
Int Immunopharmacol ; 139: 112771, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39074418

RESUMEN

Asthma is the most prevalent chronic inflammatory disease of the airways in children. The most prevalent phenotype of asthma is eosinophilic asthma, which is driven by a Th2 immune response and can be effectively managed by inhaled corticosteroid therapy. However, there are phenotypes of asthma with Th17 immune response that are insensitive to corticosteroid therapy and manifest a more severe phenotype. The treatment of this corticosteroid-insensitive asthma is currently immature and requires further attention. The objective of this study is to elucidate the regulation of the Hedgehog signaling pathway in Th17 cell differentiation in asthma. The study demonstrated that both Smo and Gli3, key components of the Hedgehog signaling pathway, were upregulated in Th17 polarization in vitro and in a Th17-dominant asthma model in vivo. Inhibiting Smo with a small molecule inhibitor or genetically knocking down Gli3 was found to suppress Th17 polarization. Smo was found to increase in Th1, Th2, Th17 and Treg polarization, while Gli3 specifically increased in Th17 polarization. ChIP-qPCR analyses indicated that Gli3 can directly interact with IL-6 in T cells, inducing STAT3 phosphorylation and promoting Th17 cell differentiation. Furthermore, the study demonstrated a correlation between elevated Gli3 expression and IL-17A and IL-6 expression in children with asthma. In conclusion, the study demonstrated that the Hedgehog signaling pathway plays an important role in the pathogenesis of asthma, as it regulates the differentiation of Th17 cells through the IL-6/STAT3 signaling. This may provide a potential therapeutic target for corticosteroid-insensitive asthma driven by Th17 cells.


Asunto(s)
Asma , Diferenciación Celular , Proteínas Hedgehog , Interleucina-6 , Factor de Transcripción STAT3 , Transducción de Señal , Células Th17 , Proteína Gli3 con Dedos de Zinc , Asma/inmunología , Asma/metabolismo , Asma/tratamiento farmacológico , Células Th17/inmunología , Factor de Transcripción STAT3/metabolismo , Animales , Interleucina-6/metabolismo , Diferenciación Celular/efectos de los fármacos , Proteínas Hedgehog/metabolismo , Humanos , Proteína Gli3 con Dedos de Zinc/metabolismo , Proteína Gli3 con Dedos de Zinc/genética , Ratones , Niño , Masculino , Receptor Smoothened/metabolismo , Receptor Smoothened/genética , Femenino , Ratones Endogámicos BALB C , Modelos Animales de Enfermedad , Células Cultivadas , Proteínas del Tejido Nervioso
16.
Bioorg Chem ; 151: 107618, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39003940

RESUMEN

An unprecedented spiro-C-glycoside adduct, heteryunine A (1), along with two uncommon alkaloids featuring a 2,3-diketopiperazine skeleton, heterpyrazines A (2) and B (3), were discovered in the roots of Heterosmilax yunnanensis. The detailed spectroscopic analysis helped to clarify the planar structures of these compounds. Compound 1, containing 7 chiral centers, features a catechin fused with a spiroketal and connects with a tryptophan derivative by a CC bond. Its complex absolute configuration was elucidated by rotating frame overhauser enhancement spectroscopy (ROESY), specific rotation, and the 13C nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculation. The possible biosynthetic routes for 1 were deduced. Compounds 1 and 2 showed significant antifibrotic effects and further research revealed that they inhibited the activation, migration and proliferation of hepatic stellate cells (HSCs) through suppressing the activity of Ras homolog family member A (RhoA).


Asunto(s)
Catequina , Proliferación Celular , Triptófano , Catequina/química , Catequina/farmacología , Catequina/aislamiento & purificación , Triptófano/química , Triptófano/farmacología , Proliferación Celular/efectos de los fármacos , Estructura Molecular , Relación Estructura-Actividad , Antifibróticos/farmacología , Antifibróticos/química , Antifibróticos/aislamiento & purificación , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Relación Dosis-Respuesta a Droga , Movimiento Celular/efectos de los fármacos , Animales , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Humanos , Raíces de Plantas/química
17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(7): 803-806, 2024 Jul 10.
Artículo en Chino | MEDLINE | ID: mdl-38946361

RESUMEN

OBJECTIVE: To explore the application of an automatic slide-dropping instrument in bone marrow chromosomal karyotyping. METHODS: The effects of manual and automatic dropping methods under different environmental humidity were retrospectively analyzed, and the repeatability of the automatic dropping method was analyzed. RESULTS: No statistical difference was found between the results of automatic and manual dropping methods under the optimum ambient humidity and high humidity (P > 0.05). At low humidity, there was a statistical difference between the two methods (P < 0.05). With regard to the repeatability, the coefficient of variations of the automatic dropping method for the number of split phases, the rate of good dispersion and the rate of overlap were all lower than those of the manual dropping method. A statistical difference was also found in the number of split phases (P < 0.05) but not in the discrete excellent rate and overlapping rate between the two methods (P > 0.05). CONCLUSION: Better effect can be obtained by the automatic dropping instrument. It is suggested to gradually replace manual work with machine.


Asunto(s)
Cariotipificación , Humanos , Cariotipificación/métodos , Adulto , Femenino , Masculino , Médula Ósea , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven , Adolescente , Humedad , Automatización , Niño , Anciano , Preescolar
18.
iScience ; 27(7): 110218, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38993672

RESUMEN

Timely adjustments of antibiotic and corticosteroid treatments are vital for patients with diffuse parenchymal lung diseases (DPLDs). In this study, 41 DPLD patients with negative metagenomic next-generation sequencing (mNGS) results who were responsive to corticosteroids were enrolled. Among these patients, about 26.8% suffered from drug-induced DPLD, while 9.8% presented autoimmune-related DPLD. Following the report of the negative mNGS results, in 34 patients with complete antibiotics administration profiles, 79.4% (27/34) patients discontinued antibiotics after receiving negative mNGS results. Moreover, 70.7% (29/41) patients began or increased the administration of corticosteroid upon receipt of negative mNGS results. In the microbiota analysis, Staphylococcus and Stenotrophomonas showed higher detection rates in patients with oxygenation index (OI) below 300, while Escherichia and Stenotrophomonas had higher abundance in patients with pleural effusion. In summary, our findings demonstrated the clinical significance of mNGS in assisting the antibiotic and corticosteroid treatment adjustments in corticosteroid-responsive DPLD. Lung microbiota may imply the severity of the disease.

19.
Clin Transl Sci ; 17(7): e13889, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39049181

RESUMEN

Esophageal and gastric varices (EGV) bleeding is a dangerous side effect of liver cirrhosis. Ascites may affect the effectiveness of carvedilol in preventing EGV rebleeding. A retrospective analysis was done on patients with EGV bleeding who visited our gastroenterology department between January 1, 2015, and October 29, 2020, and were given carvedilol therapy again. Patients were classified based on whether they had ascites. The primary outcome was EGV rebleeding. A total of 286 patients were included, with a median follow-up of 24.0 (19.0-42.0) months, comprising those without ascites (N = 155) and those with ascites (N = 131). The mean age of the patients was 55.15 ± 12.44 years, and 177 (61.9%) of them were men. There were 162 (56.6%) Child-Pugh A grades. The etiology of cirrhosis included 135 (47.2%) cases of hepatitis B. After carvedilol therapy, the patient's portal vein diameter (DPV) was widened (p < 0.05), velocity of portal vein (VPV) was slowed (p = 0.001). During the 1-year follow-up, patients with ascites had a substantially higher rebleeding rate than patients without ascites, with 24 (18.3%) versus 13 (8.4%), respectively (p = 0.013). On univariate analysis, ascites was a risk factor for rebleeding (p = 0.015). The multivariate analysis remained significant after adjusting for age, gender, etiology of cirrhosis, and previous endoscopic treatment, with OR of 2.37 (95% CI: 1.12-5.04; p = 0.025). Ascites was a risk factor for EGV rebleeding in patients undergoing carvedilol therapy. After carvedilol therapy, the patient's DPV was widened and VPV was slowed.


Asunto(s)
Ascitis , Carvedilol , Várices Esofágicas y Gástricas , Hemorragia Gastrointestinal , Cirrosis Hepática , Humanos , Carvedilol/uso terapéutico , Carvedilol/administración & dosificación , Carvedilol/efectos adversos , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Cirrosis Hepática/complicaciones , Cirrosis Hepática/tratamiento farmacológico , Ascitis/tratamiento farmacológico , Ascitis/etiología , Estudios Retrospectivos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/prevención & control , Anciano , Adulto , Resultado del Tratamiento , Recurrencia , Vena Porta
20.
Nat Commun ; 15(1): 4953, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858363

RESUMEN

Nonreciprocal quantum transport effect is mainly governed by the symmetry breaking of the material systems and is gaining extensive attention in condensed matter physics. Realizing electrical switching of the polarity of the nonreciprocal transport without external magnetic field is essential to the development of nonreciprocal quantum devices. However, electrical switching of superconducting nonreciprocity remains yet to be achieved. Here, we report the observation of field-free electrical switching of nonreciprocal Ising superconductivity in Fe3GeTe2/NbSe2 van der Waals (vdW) heterostructure. By taking advantage of this electrically switchable superconducting nonreciprocity, we demonstrate a proof-of-concept nonreciprocal quantum neuronal transistor, which allows for implementing the XOR logic gate and faithfully emulating biological functionality of a cortical neuron in the brain. Our work provides a promising pathway to realize field-free and electrically switchable nonreciprocity of quantum transport and demonstrate its potential in exploring neuromorphic quantum devices with both functionality and performance beyond the traditional devices.

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