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1.
Dev Neurosci ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955163

RESUMEN

INTRODUCTION: Neurosteroids have a variety of neurological functions, such as neurite growth, neuroprotection, myelination, and neurogenesis. P450scc, encoded by CYP11A1 gene, is the cholesterol side chain cleavage enzyme that catalyzes the first and rate limiting step in the steroidogenesis. In this study, we examine the dendritic morphology in developing hippocampal neurons of Cyp11a1 null mice at P15, a critical period for synapse formation and maturation. METHODS: Knockout mice were maintained until P15 with hormone administration. The Golgi-Cox method stained CA1 and CA3 pyramidal neurons in the hippocampus to reveal dendritic morphology. RESULTS: We demonstrated that Cyp11a1 null mice usually die within 7 days after birth and thus collected brain samples at postnatal day 5 (P5) for examination. There were significant shrinkage of dendrite size and diminishment of dendritic branching in CA1 and CA3 pyramidal neurons in the hippocampus of Cyp11a1 null mice, suggesting a developmental delay. We wonder if this delay may catch up later in life. Since the age of P15 is a critical period for synapse formation and maturation, the Cyp11a1 null mice were rescued by receiving hormone administration until P15 that the dendritic morphology in the developing hippocampal neurons could be examined. The results indicated that the total dendritic length, number of dendritic branches, as well as dendritic arborization in the CA1 and CA3 pyramidal neurons are significantly decreased in P15 knockout mice when compared to the wild type. The spine densities were also significantly decreased. In addition, the western blot analysis revealed decrease PSD-95 expression levels in the knockout mice compared to the wild type at P15. CONCLUSION: These results suggested that Cyp11a1 deficiency impairs the dendritic structures in the developing hippocampal pyramidal neurons.

2.
Heliyon ; 10(11): e32616, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38961961

RESUMEN

The study aimed to evaluate the impact of varying modulus of elasticity (MOE) values of dental implants on the deformation and von Mises stress distribution in implant systems and peri-implant bone tissues under dynamic cyclic loading. The implant-bone interface was characterised as frictional contact, and the initial stress was induced using the interference fit method to effectively develop a finite element model for an immediately loaded implant-supported denture. Using the Ansys Workbench 2021 R2 software, an analysis was conducted to examine the deformation and von Mises stress experienced by the implant-supported dentures, peri-implant bone tissue, and implants under dynamic loading across three simulated masticatory cycles. These findings were subsequently evaluated through a comparative analysis. The suprastructures showed varying degrees of maximum deformation across zirconia (Zr), titanium (Ti), low-MOE-Ti, and polyetheretherketone (PEEK) implant systems, registering values of 103.1 µm, 125.68 µm, 169.52 µm, and 844.06 µm, respectively. The Zr implant system demonstrated the lowest values for both maximum deformation and von Mises stress (14.96 µm, 86.71 MPa) in cortical bone. As the MOE increased, the maximum deformation in cancellous bone decreased. The PEEK implant system exhibited the highest maximum von Mises stress (59.12 MPa), whereas the Ti implant system exhibited the lowest stress (22.48 MPa). Elevating the MOE resulted in reductions in both maximum deformation and maximum von Mises stress experienced by the implant. Based on this research, adjusting the MOE of the implant emerged as a viable approach to effectively modify the biomechanical characteristics of the implant system. The Zr implant system demonstrated the least maximum von Mises stress and deformation, presenting a more favourable quality for preserving the stability of the implant-bone interface under immediate loading.

3.
Nat Commun ; 15(1): 5628, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965215

RESUMEN

The control of a molecule's geometry, chirality, and physical properties has long been a challenging pursuit. Our study introduces a dependable method for assembling D3-symmetric trigonal bipyramidal coordination cages. Specifically, D2h-symmetric anions, like oxalate and chloranilic anions, self-organize around a metal ion to form chiral-at-metal anionic complexes, which template the formation of D3-symmetric trigonal bipyramidal coordination cages. The chirality of the trigonal bipyramid is determined by the point chirality of chiral amines used in forming the ligands. Additionally, these cages exhibit chiral selectivity for the included chiral-at-metal anionic template. Our method is broadly applicable to various ligand systems, enabling the construction of larger cages when larger D2h-symmetric anions, like chloranilic anions, are employed. Furthermore, we successfully produce enantiopure trigonal bipyramidal cages with anthracene-containing backbones using this approach, which would be otherwise infeasible. These cages exhibit circularly polarized luminescence, which is modulable through the reversible photo-oxygenation of the anthracenes.

4.
Anal Methods ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38973656

RESUMEN

A fluorescent sensor for highly selective and ultrasensitive detection of acetylsalicylic acid (ASA), succinic acid (SA), and ascorbic acid (AA) was reported. The water-soluble fluorescent ligand salicylic acid (Sal) was generated through catalyzing ASA by the hydrolase activity of zeolitic-imidazolate framework-8 (ZIF-8) or natural esterase (Est). The Sal can coordinate with 2-methylimidazole (2-MIm) and Ln(III) to form a fluorescent lanthanide coordination polymer (LCP), which has a fluorescence emission peak with the maximum wavelength at 412 nm (the excitation wavelength at 300 nm). Therefore, the detection of ASA can be achieved through the fluorescence intensity changes of LCPs in the system, which has comparable sensitivity and good selectivity (linear range of 0.031-1.00 mM and LODs of 11.72 and 3.22 µM) as compared to a direct reaction between Est/ZIF-8 and ASA for detecting ASA (linear range of 0.05-1.20 mM and limits of detection (LODs) of 4.43 and 4.58 µM). Furthermore, upon the addition of SA and AA, the fluorescence intensity of the reaction system can be enhanced and weakened through changing the energy resonance transfer pathways and affecting the enzymatic reaction process, respectively, realizing their sensitive and selective fluorescence detection. The established fluorescent sensors can work well in a wide linear range of SA concentrations from 0 to 2.50 mM (Est-based reaction system) and 0 to 1.50 mM (ZIF-8-based reaction system) with the LODs of 0.032 and 0.028 mM, respectively. The linear ranges of AA concentrations are from 0.0078 to 0.25 mM (Est-based reaction system) and 0.0078 to 0.13 mM (ZIF-8-based reaction system) with the LODs of 2.54 and 3.80 µM, respectively. The established sensors were successfully used in the detection of SA in rabbit plasma, with a recovery of 84.0%-98.7%. Additionally, the contents of ASA in Aspirin Enteric-Coated tablets and AA in vitamin C tablets were also determined by the developed methods.

5.
Int J Pharm ; 661: 124422, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38977163

RESUMEN

The challenges posed by intractable relapse and metastasis in cancer treatment have led to the development of various forms of photodynamic therapy (PDT). However, traditional drug delivery systems, such as virus vectors, liposomes, and polymers, often suffer from issues like desynchronized drug release, carrier instability, and drug leakage during circulation. To address these problems, we have developed a dual-prodrug nanogel (PVBN) consisting of Pyro (Pyropheophorbide a) and SAHA (Vorinostat) bound to BSA (Bovine Serum Albumin), which facilitates synchronous and spontaneous drug release in situ within the lysosome. Detailed results indicate that PVBN-treated tumor cells exhibit elevated levels of ROS and Acetyl-H3, leading to necrosis, apoptosis, and cell cycle arrest, with PDT playing a dominant role in the synergistic therapeutic effect. Furthermore, the anti-tumor efficacy of PVBN was validated in melanoma-bearing mice, where it significantly inhibited tumor growth and pulmonary metastasis. Overall, our dual-prodrug nanogel, formed by the binding of SAHA and Pyro to BSA and releasing drugs within the lysosome, represents a novel and promising strategy for enhancing the clinical efficacy of photochemotherapy.

6.
Sci Rep ; 14(1): 15956, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38987349

RESUMEN

With global warming, heat stress has become an important factor that seriously affects crop yield and quality. Therefore, understanding plant responses to heat stress is important for agricultural practice, but the molecular mechanism of high-temperature tolerance in garlic remains unclear. In this study, 'Xusuan No. 6' was used as the experimental material. After heat stress for 0 (CK), 2 and 24 h, transcriptome sequencing was used to screen metabolic pathways and differentially expressed genes (DEGs) closely related to heat stress and was further verified by quantitative real-time polymerase chain reaction (qRT-PCR). A total of 86,110 unigenes obtained from the raw transcriptome sequencing data were spliced. After 2 h of heat treatment, the expression levels of 8898 genes increased, and 3829 genes were decreased in leaves. After 24 h, the expression levels of 7167 genes were upregulated, and 3176 genes were downregulated. Gene Ontology enrichment analysis showed that DEGs were mainly enriched in seven categories: cellular processes, metabolic processes, binging, catalytic activity, cellular anatomical entity and protein-containing complex response to stimulus. Kyoto Encyclopedia of Genes and Genomes pathway enrichment showed that DEGs are involved in protein processing in the endoplasmic reticulum, plant hormone signal transduction, phenylpropanoid biosynthesis, and photosynthetic antenna proteins. Six genes were selected and further verified by qRT-PCR. In this study, the full-length transcriptome of garlic was constructed, and the regulatory genes related to the heat resistance of garlic were studied. Taken together, these findings can provide a theoretical basis for the cloning of heat resistance genes in garlic and for the analysis of heat resistance mechanisms.


Asunto(s)
Ajo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Respuesta al Choque Térmico , Transcriptoma , Ajo/genética , Ajo/metabolismo , Respuesta al Choque Térmico/genética , Ontología de Genes , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
ESC Heart Fail ; 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39034632

RESUMEN

AIMS: To assess the stage of acute kidney injury (AKI), as an index of organ perfusion, combined with shock severity, measured by the Society for Cardiovascular Angiography and Interventions (SCAI) shock stage classification, to stratify the risk of mortality in patients diagnosed with cardiogenic shock (CS) and supported with venoarterial extracorporeal membrane oxygenation (VA ECMO). METHODS ANS RESULTS: From January 2018 to December 2020, consecutive adult patients diagnosed with CS and received VA ECMO were retrospectively evaluated. The highest AKI stage within 48 h after ECMO initiation was assessed using the Kidney Disease: Improving Global Outcomes criteria. We included 216 patients with a mean age of 58.8 years and 31.0% were females. 88.4% of patients received ECMO for postcardiotomy, while 11.6% for medical CS. The total in-hospital mortality was 53.2%. AKI occurred in 182 (84.3%) patients receiving ECMO for CS. AKI stage 0, 1, 2, and 3 were present in 15.7%, 17.6%, 18.1%, and 48.6% of patients with in-hospital mortality of 26.5%, 26.3%, 61.5%, and 68.6%, respectively (P < 0.001). The AKI stage (P < 0.001), SCAI shock stage before ECMO (P = 0.008), and NYHA ≥ Class III on admission (P = 0.044) were independent predictors of in-hospital mortality. The area under the receiver operating characteristic curve of 0.754 (95% confidence interval: 0.690 to 0.811) for AKI stage combined with SCAI shock stage was better than those for AKI stage (0.676), SCAI shock stage (0.657), serum lactate level (0.682), SOFA score (0.644), SVAE score (0.582), and VIS score (0.530) prior to ECMO. CONCLUSIONS: In this single-center CS population who received VA ECMO for circulatory support, predominantly postcardiotomy cases, AKI occurred in 84.3% of the patients. AKI stage, as an index of organ perfusion combined with shock severity measured by the SCAI shock classification, demonstrates a good correlation with in-hospital mortality.

8.
Colloids Surf B Biointerfaces ; 242: 114079, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39029247

RESUMEN

Water-in-water (W/W) Pickering emulsions, exhibit considerable potential in the food and pharmaceutical fields owing to their compartmentalization and high biocompatibility. However, constrained by the non-uniform distribution of shear forces during emulsification or the spatial obstruction in polydimethylsiloxane (PDMS) passive microfluidic platform, the existing methods cannot generate monodisperse W/W Pickering emulsions with high particle coverage rate, thereby limiting their applications. Herein, a novel microfluidic system is designed for the preparation of monodisperse and highly particle-covered W/W Pickering emulsions under mild conditions. pH-responsive Polyethylene glycol (PEG)/phosphate aqueous two-phase system (ATPS) is used for the emulsions' preparation. Notably, a coverage rate of 96 ± 3 % is obtained by adjusting the length of the helical coiled tube, as well as the size and contact angle of genipin cross-linked BSA (BSA-GP) particles. Moreover, these W/W Pickering emulsions, with surfaces almost completely covered, can maintain monodisperse (Ncoal = 1.18 ± 0.03) for one day. Furthermore, the results of ranitidine hydrochloride (RH) release demonstrated that the drug release rate of W/W Pickering emulsions in the simulated gastric fluid (SGF) was 10 times faster than that in the neutral solution. We believe that the highly particle-covered monodisperse W/W Pickering emulsions possess great potential applications in bioencapsulation for foods and drug delivery.

9.
Int J Biol Macromol ; : 133952, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39029829

RESUMEN

Gastric cancer(GC)is one of the most common gastrointestinal malignant tumors in the world, requiring the development of novel therapeutic agents with reduced toxicity. Rehmannia polysaccharide (RPS) possesses immunomodulatory and anti-tumor properties, yet its efficacy is suboptimal. To enhance its biological activity, we subjected RPS to molecular modifications, resulting in phosphorylated Rehmannia polysaccharides (P-RPS). Using the mixed phosphate method, we synthesized P-RPS and optimized the synthesis conditions through a combination of single-factor and response surface methodologies. In vitro studies on P-RPS's anti-tumor activity showed no direct influence on the viability of GC cells. However, P-RPS induced the transformation of PMA-activated THP-1 cells into the M1 phenotype. We collected conditioned medium (CM) of THP-1 cells to stimulate gastric cancer cells and CM-P-RPS significantly promoted apoptosis of gastric cancer cells and inhibited cell proliferation, and reduced cell migration. Mechanistically, CM-P-RPS inhibits the Wnt/ß-catenin signaling pathway through LGR6, leading to the suppression of tumor growth. Furthermore, P-RPS demonstrated a significant inhibitory effect on tumor growth in vivo, suggesting its potential as a promising therapeutic agent for GC treatment.

10.
J Am Chem Soc ; 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39004825

RESUMEN

High-entropy intermetallic (HEI) nanocrystals, composed of multiple elements with an ordered structure, are of immense interest in heterogeneous catalysis due to their unique geometric and electronic structures and the cocktail effect. Despite tremendous efforts dedicated to regulating the metal composition and structures with advanced synthetic methodologies to improve the performance, the surface structure, and local chemical order of HEI and their correlation with activity at the atomic level remain obscure yet challenging. Herein, by determining the three-dimensional (3D) atomic structure of quinary PdFeCoNiCu (PdM) HEI using atomic-resolution electron tomography, we reveal that the local chemical order of HEI regulates the surface electronic structures, which further mediates the alkyl-substitution-dependent alkyne semihydrogenation. The 3D structures of HEI PdM nanocrystals feature an ordered (intermetallic) core enclosed by a disordered (solid-solution) shell rather than an ordered surface. The lattice mismatch between the core and shell results in apparent near-surface distortion. The chemical order of the intermetallic core increases with annealing temperature, driving the electron redistribution between Pd and M at the surface, but the surface geometrical (chemically disordered) configurations and compositions are essentially unchanged. We investigate the catalytic performance of HEI PdM with different local chemical orders toward semihydrogenation across a broad range of alkynes, finding that the electron density of surface Pd and the hindrance effect of alkyl substitutions on alkynes are two key factors regulating selective semihydrogenation. We anticipate that these findings on surface atomic structure will clarify the controversy regarding the geometric and/or electronic effects of HEI catalysts and inspire future studies on tuning local chemical order and surface engineering toward enhanced catalysts.

11.
Biomed Rep ; 21(2): 124, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39006508

RESUMEN

Acute pancreatitis (AP) is a common inflammatory disorder of the exocrine pancreas that causes severe morbidity and mortality. Although the pathophysiology of AP is poorly understood, a substantial body of evidence suggests some critical events for this disease, such as dysregulation of digestive enzyme production, cytoplasmic vacuolization, acinar cell death, edema formation, and inflammatory cell infiltration into the pancreas. Oxidative stress plays a role in the acute inflammatory response. The present review clarified the role of oxidative stress in the occurrence and development of AP by introducing oxidative stress to disrupt cellular Ca2+ balance and stimulating transcription factor activation and excessive release of inflammatory mediators for the application of antioxidant adjuvant therapy in the treatment of AP.

12.
Int J Biol Macromol ; 275(Pt 1): 133397, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38960261

RESUMEN

Flavor is considered one of the most significant factors affecting food quality. However, it is often susceptible to environmental factors, so encapsulation is highly necessary to facilitate proper handling and processing. In this study, the structural changes in starch encapsulation and their effects on flavor retention were investigated using indica starch (RS) as a matrix to encapsulate three flavoring compounds, namely nonanoic acid, 1-octanol, and 2-pentylfuran. The rheological and textural results suggested that the inclusion of flavor compounds improved the intermolecular interactions between starch molecules, resulting in a significant increase in the physicochemical properties of starch gels in the order: nonanoic acid > 1-octanol > 2-pentylfuran. The XRD results confirmed the successful preparation of v-starch. Additionally, the inclusion complexes (ICs) were characterized using FT-IR, SEM, and DSC techniques. The results showed that v-starch formed complexes with Flavor molecules. The higher enthalpy of the complexes suggested that the addition of alcohols and acids could improve the intermolecular complexation between starch molecules. The retention rates of three flavor compounds in starch were determined using HS-GC, with the values of 51.7 %, 32.37 %, and 35.62 %. Overall, this study provides insights into novel approaches to enhance the quality and flavor retention, improve the storability and stability, reduce losses during processing and storage, and extend the shelf life of starchy products.

13.
Aging Med (Milton) ; 7(3): 350-359, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38975311

RESUMEN

Objective: The objective of the present study was to explore the correlation between the advanced lung cancer inflammation index (ALI) and in-hospital mortality among patients diagnosed with community-acquired pneumonia (CAP). Methods: Data from the Medical Information Mart for Intensive Care-IV database were adopted to analyze the in-hospital mortality of ICU patients with CAP. Upon admission to the ICU, fundamental data including vital signs, critical illness scores, comorbidities, and laboratory results, were collected. The in-hospital mortality of all CAP patients was documented. Multivariate logistic regression (MLR) models and restricted cubic spline (RCS) analysis together with subgroup analyses were conducted. Results: This study includes 311 CAP individuals, involving 218 survivors as well as 93 nonsurvivors. The participants had an average age of 63.57 years, and the females accounted for approximately 45.33%. The in-hospital mortality was documented to be 29.90%. MLR analysis found that ALI was identified as an independent predictor for in-hospital mortality among patients with CAP solely in the Q1 group with ALI ≤ 39.38 (HR: 2.227, 95% CI: 1.026-4.831, P = 0.043). RCS analysis showed a nonlinear relationship between the ALI and in-hospital mortality, with a turning point at 81, and on the left side of the inflection point, a negative correlation was observed between ALI and in-hospital mortality (HR: 0.984, 95% CI: 0.975-0.994, P = 0.002). The subgroup with high blood pressure showed significant interaction with the ALI. Conclusion: The present study demonstrated a nonlinear correlation of the ALI with in-hospital mortality among individuals with CAP. Additional confirmation of these findings requires conducting larger prospective investigations.

14.
Environ Pollut ; 358: 124486, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38972563

RESUMEN

Chlorinated volatile organic compounds (Cl-VOCs) have dramatically biotoxicity and environmental persistence due to the presence of chlorine atoms, seriously jeopardizing ecological security and human health. Dichloromethane (DCM) as a model pollutant, is widely applied in solvents, extractants and cleaning agents in the pharmaceutical, chemical and food industries. In this study, highly biocompatible and conductive carbon cloth-titanium nitride-polyaniline (CC-TiN-PANI) bioelectrodes were obtained for DCM degradation in microbial electrolysis cell (MEC). The good adhesion of TiN and PANI on the electrode surface was demonstrated. The degradation kinetics were fitted by the Haldane model, compared to the CC bioelectrode (0.8 h-1), the proportion of maximum degradation rates to half-saturation concentration (Vmax/Km) of CC-TiN (1.4 h-1) and CC-TiN-PANI (2.2 h-1) bioelectrodes were enhanced by 1.8 and 2.8 times, respectively. Microbial community structure analysis illuminated that the dominant genera on the biofilm were Alicycliphilus and Hyphomicrobium, and the abundance was enhanced significantly with the modification of TiN and PANI. The dechlorination of DCM to formaldehyde could be catalyzed by DCM dehalogenase (DcmA) or by haloalkane dehalogenase (DhlA). And further oxidized to formate: 1) direct catalyzed by formaldehyde dehydrogenase (FdhA); 2) conjugated with glutathione by S-(hydroxymethyl)-glutathione synthase (Gfa), S-(hydroxymethyl)-glutathione dehydrogenase (FrmA) and S-formyl-glutathione hydrolase (FrmB); 3) conjugation with tetrahydrofolate (H4F) and/or tetrahydromethanopterin.

15.
Can J Cardiol ; 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38981559

RESUMEN

BACKGROUND: To assess the safety of high-moderate (24.1-28.0°C) and low-moderate (20.1-24.0°C) systemic hypothermia (MHCA) during circulatory arrest in patients with acute DeBakey I aortic dissection (DeBakey I AAD), particularly concerning spinal cord protection. METHODS: Between 2009 and 2020, 1759 patients with DeBakey I AAD who underwent frozen elephant trunk and total arch replacement surgery at a tertiary center were divided into preoperative malperfusion (viscera, spinal cord, or lower extremities) and non-malperfusion subgroups. The baseline differences were balanced using propensity score matching. Prognoses were compared between those who were subjected to high-MHCA (nasopharyngeal temperature, 24.1-28.0°C) and low-MHCA (20.1-24.0°C). RESULTS: In the non-malperfusion subgroup (n=1389), 469 pairs of matched patients showed lower in-hospital mortality and incidence of acute kidney injury in the high-MHCA group than in the low-MHCA group (in-hospital mortality, 7.0% vs. 10.2%, P=0.01; acute kidney injury, 57.1% vs. 64.6%, P<0.01). The duration of mechanical ventilation was shorter in the high-MHCA group than that in the low-MHCA group (P=0.03). No significant difference in the incidence of paraplegia was observed between the two groups. In the malperfusion subgroup (n=370), 112 pairs of matched patients showed a higher incidence of paraplegia in the high-MHCA group than in the low-MHCA group (15.9% vs. 6.5%, P=0.04). CONCLUSIONS: The safety of high-MHCA, a commonly used temperature management strategy during aortic arch surgery, was recognized in most patients with DeBakey I AAD. However, among patients with preoperative distal organ malperfusion, low-MHCA may be more appropriate because of an increased risk of postoperative paraplegia associated with high-MHCA.

16.
Angew Chem Int Ed Engl ; : e202407658, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982589

RESUMEN

Metallene is considered as an emerging family of electrocatalysts due to its atomically layered structure and unique surface stress. Here we propose a strategy to modulate the Bader charge transfer (BCT) between Pd surface and oxygenated intermediates via p-d electronic interaction by introducing single-atomp-block metal (M = In, Sn, Pb, Bi) into Pd metallene nanosheets towards efficient oxygen reduction reaction (ORR). X-ray absorption and photoelectron spectroscopy suggests that doping p-block metals could facilitate electron transfer to Pd sites and thus downshift the d-band center of Pd and weaken the adsorption energy of O intermediates. Among them, the developed Bi-Pd metallene shows extraordinarily high ORR mass activity of 11.34 A mgPd-1 and 0.86 A mgPd-1 at 0.9 V and 0.95 V in alkaline solution, respectively, representing the best Pd-based ORR electrocatalysts ever reported. In the cathode of a Zinc-air battery, Bi-Pd metallene could achieve an open-circuit voltage of 1.546 V and keep stable for 760 h at 10 mA cm-2. Theoretical calculations suggest that the BCT between Pd surface and *OO intermediates greatly affects the bond length between them (dPd-*OO) and Bi doping could appropriately reduce the amount of BCT and stretch the dPd-*OO, thus enhancing the ORR activity.

17.
Front Cell Infect Microbiol ; 14: 1397724, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38966251

RESUMEN

Cryptococcus neoformans is at the top of the list of "most wanted" human pathogens. Only three classes of antifungal drugs are available for the treatment of cryptococcosis. Studies on antifungal resistance mechanisms are limited to the investigation of how a particular antifungal drug induces resistance to a particular drug, and the impact of stresses other than antifungals on the development of antifungal resistance and even cross-resistance is largely unexplored. The endoplasmic reticulum (ER) is a ubiquitous subcellular organelle of eukaryotic cells. Brefeldin A (BFA) is a widely used chemical inducer of ER stress. Here, we found that both weak and strong selection by BFA caused aneuploidy formation in C. neoformans, mainly disomy of chromosome 1, chromosome 3, and chromosome 7. Disomy of chromosome 1 conferred cross-resistance to two classes of antifungal drugs: fluconazole and 5-flucytosine, as well as hypersensitivity to amphotericin B. However, drug resistance was unstable, due to the intrinsic instability of aneuploidy. We found overexpression of AFR1 on Chr1 and GEA2 on Chr3 phenocopied BFA resistance conferred by chromosome disomy. Overexpression of AFR1 also caused resistance to fluconazole and hypersensitivity to amphotericin B. Furthermore, a strain with a deletion of AFR1 failed to form chromosome 1 disomy upon BFA treatment. Transcriptome analysis indicated that chromosome 1 disomy simultaneously upregulated AFR1, ERG11, and other efflux and ERG genes. Thus, we posit that BFA has the potential to drive the rapid development of drug resistance and even cross-resistance in C. neoformans, with genome plasticity as the accomplice.


Asunto(s)
Aneuploidia , Antifúngicos , Brefeldino A , Cryptococcus neoformans , Farmacorresistencia Fúngica , Cryptococcus neoformans/efectos de los fármacos , Cryptococcus neoformans/genética , Brefeldino A/farmacología , Antifúngicos/farmacología , Farmacorresistencia Fúngica/genética , Fluconazol/farmacología , Anfotericina B/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Pruebas de Sensibilidad Microbiana , Flucitosina/farmacología , Humanos , Estrés del Retículo Endoplásmico/efectos de los fármacos
19.
ACS Appl Mater Interfaces ; 16(24): 31597-31609, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38850560

RESUMEN

By overcoming interspecies differences and mimicking the in vivo microenvironment, three-dimensional (3D) in vitro corneal models have become a significant novel tool in contemporary ophthalmic disease research. However, existing 3D corneal models struggle to replicate the actual human corneal environment, especially the dome-shaped physiological structure with adjustable curvature. Addressing these challenges, this study introduces a straightforward method for fabricating collagen/chitosan-alginate eyeball-shaped gel microspheres with a Janus structure via a two-phase aqueous system, used subsequently to construct in vitro 3D corneal epithelial tissue models. By adjusting the diameter ratio of collagen/chitosan to alginate droplets, we can create eyeball-shaped gel microspheres with varying curvatures. Human corneal epithelial cells were seeded on the surfaces of these microspheres, leading to the formation of in vitro 3D corneal epithelial tissues characterized by dome-like multilayers and tight junctions. Additionally, the model demonstrated responsiveness to UVB exposure through the secretion of reactive oxygen species (ROS) and proinflammatory factors. Therefore, we believe that in vitro 3D corneal epithelial tissue models with dome-shaped structures hold significant potential for advancing ophthalmic research.


Asunto(s)
Alginatos , Quitosano , Epitelio Corneal , Microesferas , Humanos , Epitelio Corneal/citología , Alginatos/química , Quitosano/química , Colágeno/química , Ingeniería de Tejidos , Células Epiteliales/metabolismo , Células Epiteliales/citología , Geles/química , Especies Reactivas de Oxígeno/metabolismo
20.
J Environ Manage ; 363: 121382, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38852416

RESUMEN

Vegetation restoration not only extensively reshapes spatial land use patterns but also profoundly affects the dynamics of runoff and sediment loss. However, the influence of vegetation restoration on runoff and sediment yield from a regional perspective are scarce. This study therefore focused on 85 sites within the "Grain for Green" Project (GGP) region on the Loess Plateau, to investigate the impacts of the GGP on soil erosion. The results revealed a notable reduction in sediment loss and runoff due to vegetation restoration. Since the inception of the GGP in 1999, approximately 4.1 × 106 ha of degraded lands have been converted into forestlands, shrublands, and grasslands, resulting in an average annual reduction of 1.4 × 109 m3 in runoff and a decrease of 3.6 × 108 t in annual sediment loss on the whole Loess Plateau, with the GGP contributing approximately 26.7% of the sediment reduction in the Yellow River basin. The reduced soil erosion has mainly been regulated by vegetation cover, soil properties (clay, silt, and sand), slope, and precipitation on the Loess Plateau. The insights gained offer valuable contributions to large-scale assessments of changes in soil erosion in response to vegetation reconstruction and enhance our understanding of the spatial configurations associated with soil erosion control measures.


Asunto(s)
Conservación de los Recursos Naturales , Erosión del Suelo , Suelo , Sedimentos Geológicos , China , Monitoreo del Ambiente , Bosques
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