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2.
ACS Nano ; 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39126711

RESUMEN

The electrocatalytic carbon dioxide reduction reaction (ECRR) is promising in converting environmentally harmful CO2 into useful chemicals, but the large-scale application of this technology is seriously limited by its low efficiency and selectivity. Cu-based electrocatalysts displayed attractive ability in converting CO2 to multiple products, and the product selectivity can be manipulated through various approaches. Among them, exposing specific crystal facets through crystal facet engineering has been proven to be highly effective in obtaining specific products and has attracted numerous researchers. However, to our knowledge, few reports have systematically summarized the relationship between the crystal facet control of Cu catalysts and the catalytic products. This review begins by outlining the general mechanism of CO2 electrocatalytic reduction on Cu-based catalysts, and then summarizes the preferences of low-index and high-index Cu facets regarding product selectivity and delves into the synergistic effects between facets (including different Cu facets and interactions between Cu and non-Cu facets) and their impact on CO2 reduction reaction (CO2RR). In addition, the study of the recently developed Cu single-atom catalysts in ECRR was also introduced. Finally, we provide an outlook on the development of high-performance Cu-based catalysts for applications in CO2RR. The purpose of this review is to provide a clear vein and meaningful guidance for the following studies over the crystal facet control of Cu-based electrocatalysts.

3.
J Neuroimmunol ; 395: 578431, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39142025

RESUMEN

Efgartigimod was the first-in-class neonatal Fc receptor antagonist approved for the treatment of acetylcholine receptor antibody positive (AChR+), Myasthenia Gravis Foundation of America (MGFA) Class II-IV generalized myasthenia gravis (gMG) patients. As a novel therapy, the clinical experiences are still lacking, especially for the use of efgartigimod in manifest and impending myasthenic crisis (IMC). We reported three AChR+, gMG patients, two with myasthenic crisis (MC) and one with IMC, treated with efgartigimod. MGFA class, MG-Activity of Daily Living score (MG-ADL), Quantitative MG score (QMG), and Muscle Research Council sum score (MRC), concentration of anti-AChR antibody, IgG, globulin, and albumin, subsets of T and B lymphocyte were evaluated or measured before, during and after efgartigimod treatment. All patients showed fast and robust response to efgartigimod with marked improvement in MGFA, MG-ADL, QMG, and MRC scores. Patient 1 did not respond effectively to IVIg but was successfully rescued by add-on efgartigimod. She extubated at 7 days after the first infusion and got rid of NIV after 14-days treatment. Patient 2 and patient 3 directly used efgartigimod when symptoms were not ameliorated by adjusting of oral drugs. Patient 2 wean from BiPAP at seven days after the first infusion. Patient 3 in IMC status, overcame the severe dysphagia at three days after the first infusion. Clinical symptoms continued to improve 1-2 weeks after discharge. Concentration of anti-AChR antibody, IgG and globulin were remarkably reduced by efgartigimod treatment. Our study supported that efgartigimod could act as a fast-acting rescue therapy for patients with MC or IMC. Larger studies from multicenter are required to provide further evidence.

4.
An. bras. dermatol ; 99(4): 535-545, Jul.-Aug. 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1563713

RESUMEN

Abstract Background Cutaneous squamous cell carcinoma (CSCC) is one of the most common types of skin cancer worldwide. Therefore, the identification of biomarkers associated with CSCC progression could aid in the early detection of high-risk squamous cell carcinoma and the development of novel therapeutic strategies. Objective This study aimed to investigate the expression patterns of silent mating type Information Regulation 2 homolog 6 (SIRT6) in CSCC and its clinical significance. Methods The protein expression level of SIRT6 in tissues was detected by immunohistochemistry, and the correlation between SIRT6 expression and clinicopathological parameters in CSCC patients was analyzed. The relative expression of SIRT6 in CSCC cell lineage and tissue specimens was determined by western blotting and PCR. The effect of SIRT6 silencing on cell proliferation was evaluated using cell counting kit 8. Wound healing, transwell method, and flow cytometry were used to investigate the migration, invasion, and cell cycle distribution/apoptosis of CSCC cells after SIRT6 silencing, respectively. Western blot was used to detect the expression of EMT (Epithelial-Mesenchymal Transition), cycle, apoptosis, and other related proteins. Results The high expression of SIRT6 was correlated with the location of cancer tissue and Broder staging in CSCC patients. Knockdown of SIRT6 inhibited the proliferation, migration, invasion and EMT of CSCC cells, and promoted their apoptosis, with cells blocked in G1 phase. Study limitations No animal experiments were conducted to further verify the results. Conclusion Decreased expression of SIRT6 can inhibit the occurrence and development of CSCC.

5.
Phytomedicine ; 132: 155884, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39053245

RESUMEN

BACKGROUND: QiJu-DiHuang Wan (QJDHW), a frequently employed Chinese herbal formula, is used to treat blurred vision. Even so, it is unclear how it works in treating age-related dry eyes. OBJECTIVE: The aim of this research is to explore the potential mechanisms of QJDHW in treating dry eye using UHPLC-QE-MS, metabolomics, and network pharmacology. METHODS: Six male SD rats were segregated into control and QJDHW groups. Following intervention, The primary active ingredients in QJDHW-containing serum were identified using UHPLC-QE-MS. Metabolomics and network pharmacology were utilized to investigate potential targets and pathways involved following QJDHW use. Primary lacrimal epithelial cells were used for validation. RESULTS: A total of 425 active ingredients of QJDHW were identified, along with 210 active ingredients in QJDHW-containing serum. A comparison of QJDHW-containing serum and control serum samples revealed 40 metabolic differentiators. A total of 24 metabolites were found in QJDHW and QJDHW-containing serum. Network pharmacology identified 3,144 targets for dry eye disease, and 102 metabolite action targets were found for QJDHW-entering components. KEGG Enrichment Analysis revealed significance of HIF-1, apoptosis, cell cycle and PI3K-Akt, among others. HIF-1 and PI3K-Akt were chosen for verification in the oxidative damage model of lacrimal epithelial cells. CONCLUSION: The main active ingredients of QJDHW and its containing serum were elucidated by UHPLC-QE-MS demonstrating that QJDHW treats age-associated dry eye by inhibiting HIF1α/NF-κB through ROS inhibition and PI3K/p-AKT activation.

6.
Front Cell Infect Microbiol ; 14: 1431979, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39071166

RESUMEN

Introduction: Screening for effective antiviral compounds from traditional Mongolian medicine not only aids in the research of antiviral mechanisms of traditional medicines, but is also of significant importance for the development of new antiviral drugs targeting influenza A virus. Our study aimed to establish high-throughput, rapid screening methods for antiviral compounds against influenza A virus from abundant resources of Mongolian medicine. Methods: The use of GFP-based reporter viruses plays a pivotal role in antiviral drugs screening by enabling rapid and precise identification of compounds that inhibit viral replication. Herein, a GFP-based reporter influenza A virus was used to identify potent anti-influenza compounds within traditional Mongolian medicine. Results: Our study led to the discovery of three active compounds: Cardamonin, Curcumin, and Kaempferide, all of which exhibited significant antiviral properties in vitro. Subsequent analysis confirmed that their effectiveness was largely due to the stimulation of the antiviral signaling pathways of host cells, rather than direct interference with the viral components, such as the viral polymerase. Discussion: This study showcased the use of GFP-based reporter viruses in high-throughput screening to unearth antiviral agents from traditional Mongolian medicine, which contains rich antiviral compounds and deserves further exploration. Despite certain limitations, fluorescent reporter viruses present substantial potential for antiviral drug screening research due to their high throughput and efficiency.


Asunto(s)
Antivirales , Evaluación Preclínica de Medicamentos , Genes Reporteros , Proteínas Fluorescentes Verdes , Ensayos Analíticos de Alto Rendimiento , Virus de la Influenza A , Medicina Tradicional Mongoliana , Replicación Viral , Antivirales/farmacología , Antivirales/aislamiento & purificación , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Animales , Evaluación Preclínica de Medicamentos/métodos , Humanos , Virus de la Influenza A/efectos de los fármacos , Replicación Viral/efectos de los fármacos , Perros , Células de Riñón Canino Madin Darby , Línea Celular
7.
Cancers (Basel) ; 16(14)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39061176

RESUMEN

The early 2-factor (E2F) family of transcription factors, including E2F1 through 8, plays a critical role in apoptosis, metabolism, proliferation, and angiogenesis within glioblastoma (GBM). However, the specific functions of E2F transcription factors (E2Fs) and their impact on the malignancy of Bevacizumab (BVZ)-responsive GBM subtypes remain unclear. This study used data from The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), European Molecular Biology Laboratory's European Bioinformatics Institute (EMBL-EBI), and Gene Expression Omnibus (GEO) to explore the impact of eight E2F family members on the clinical characteristics of BVZ-responsive GBM subtypes and possible mechanisms of recurrence after BVZ treatment. Using machine learning algorithms, including TreeBagger and deep neural networks, we systematically predicted and validated GBM patient survival terms based on the expression profiles of E2Fs across BVZ-responsive GBM subtypes. Our bioinformatics analyses suggested that a significant increase in E2F8 post-BVZ treatment may enhance the function of angiogenesis and stem cell proliferation, implicating this factor as a candidate mechanism of GBM recurrence after treatment. In addition, BVZ treatment in unresponsive GBM patients may potentially worsen disease progression. These insights underscore that E2F family members play important roles in GBM malignancy and BVZ treatment response, highlighting their potential as prognostic biomarkers, therapeutic targets, and recommending precision BVZ treatment to individual GBM patients.

8.
Cell Death Dis ; 15(7): 520, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039052

RESUMEN

Aldehyde dehydrogenases superfamily (ALDHs), which are ubiquitously present in various organisms with diverse subcellular localizations, play a crucial role in regulating malignant tumor progression; Nevertheless, their involvement in clear cell renal cell carcinoma (ccRCC) has not been elucidated. In this study, we performed comprehensive bioinformatics analyses on the 19 ALDHs genes, and identified ALDH9A1 as a key contributor in ccRCC. Expression patterns and clinical relevance of ALDH9A1 were determined using bioinformatics analyses, real-time PCR, western blotting, and immunohistochemistry. To explore the underlying mechanism behind the tumor suppressor role of ALDH9A1, RNA sequencing, methylated RNA immunoprecipitation, luciferase reporter assay, mass spectroscopy, immunoprecipitation, mutational studies and immunofluorescence were employed. The impact of ALDH9A1 in ccRCC progression and metabolic programming was assessed through both in vitro and in vivo. Here, this study revealed ALDH9A1 as a tumor suppressor gene in ccRCC. The fat mass and obesity associated protein (FTO) was identified as a demethylase for ALDH9A1 mRNA, resulting in its reduced stability and expression levels in ccRCC. Functional experiments demonstrated that the deficiency of ALDH9A1 in ccRCC promoted tumor proliferation, invasion, migration and lipid accumulation. Mechanistic insights illustrated that the diminished levels of ALDH9A1 resulted in the failure to sequester nucleophosmin 1 (NPM1) within cytoplasm, thereby suppressing the transcription of IQ motif containing the GTPase-activating protein 2 (IQGAP2), subsequently activating the AKT-mTOR signaling, ultimately fostering tumor progression and lipid accumulation. In conclusion, the present study highlights the robust prognostic significance of ALDH9A1 and delivers a comprehensive understanding of ALDH9A1-NPM1-IQGAP2-AKT axis in ccRCC. These findings established a solid research foundation for novel therapeutic strategies for ccRCC patients.


Asunto(s)
Adenosina , Carcinoma de Células Renales , Neoplasias Renales , Nucleofosmina , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Humanos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Renales/genética , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Adenosina/análogos & derivados , Adenosina/metabolismo , Animales , Progresión de la Enfermedad , Línea Celular Tumoral , Ratones , Ratones Desnudos , Proliferación Celular , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Activadoras de GTPasa/metabolismo , Proteínas Activadoras de GTPasa/genética , Masculino , Femenino
9.
Diagnostics (Basel) ; 14(13)2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-39001321

RESUMEN

Single photon emission tomography/computed tomography (SPECT/CT) is a mature imaging technology with a dynamic role in the diagnosis and monitoring of a wide array of diseases. This paper reviews the technological advances, clinical impact, and future directions of SPECT and SPECT/CT imaging. The focus of this review is on signal amplifier devices, detector materials, camera head and collimator designs, image reconstruction techniques, and quantitative methods. Bulky photomultiplier tubes (PMTs) are being replaced by position-sensitive PMTs (PSPMTs), avalanche photodiodes (APDs), and silicon PMs to achieve higher detection efficiency and improved energy resolution and spatial resolution. Most recently, new SPECT cameras have been designed for cardiac imaging. The new design involves using specialised collimators in conjunction with conventional sodium iodide detectors (NaI(Tl)) or an L-shaped camera head, which utilises semiconductor detector materials such as CdZnTe (CZT: cadmium-zinc-telluride). The clinical benefits of the new design include shorter scanning times, improved image quality, enhanced patient comfort, reduced claustrophobic effects, and decreased overall size, particularly in specialised clinical centres. These noticeable improvements are also attributed to the implementation of resolution-recovery iterative reconstructions. Immense efforts have been made to establish SPECT and SPECT/CT imaging as quantitative tools by incorporating camera-specific modelling. Moreover, this review includes clinical examples in oncology, neurology, cardiology, musculoskeletal, and infection, demonstrating the impact of these advancements on clinical practice in radiology and molecular imaging departments.

10.
Materials (Basel) ; 17(13)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38998252

RESUMEN

The fiber-reinforced composite stringer is commonly used in large civil aircraft wing structures. Under compression loads, it exhibits complex failure modes, with matrix cracking being one of the most common. The quantitative analysis of matrix failure is important and difficult. To address this issue, a multiscale method combining the generalized method of cells (GMC) and macroscopic FEM models is employed to quantitatively predict matrix damage and failure. The extent of matrix damage in the composite structure is represented by the number of failed matrix subcells within the repeating unit cells. The 3D Tsai-Hill failure criterion is established for the matrix phase, and the maximum stress failure criterion is applied to the fiber subcell. Upon meeting the criterion, the stiffnesses of the failed subcells are immediately reduced to a nominal value. In the current study, the ultimate loads, failure modes and load-displacement curves of composite stringers subjected to compressive load are obtained by the experiment approach and the proposed multiscale model. The experimental and simulation results show good agreement, and the multiscale analysis method successfully predicts the extent of matrix damage in the composite stringer under compressive load. The number of failed matrix subcells quantitatively evaluates the damage extent within a 2 × 2 GMC model. The findings reveal that matrix subcell failures primarily occur in the 45° and -45° plies of the middle part of the stringer composite.

12.
Mol Biol Rep ; 51(1): 842, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042261

RESUMEN

BACKGROUND: Although Huaier granules can be used as prospective anti-cholangiocarcinoma drugs, the mechanism of action of Huaier granules in cholangiocarcinoma is not clear. The anti-cholangiocarcinoma effect of Huaier granules was validated in cell line research. In vitro experiments were conducted to investigate the signalling pathways affected by Huaier in CCA cells. METHODS AND RESULTS: Real-time quantitative PCR (RT‒qPCR) and Western blot analysis were performed to analyse gene expression in CCA cells. MTT assays, scratch tests, and Transwell assays were used to explore the effects on the proliferation and metastasis of CCA cells. Chromatin immunoprecipitation assays were performed to reveal the potential underlying mechanisms involved. Twist1 was upregulated in human CCA tissues. In addition, its expression levels were negatively related to FBP1 expression levels. Mechanistically, Twist1 can bind to the region of the FBP1 promoter to reduce its expression. Huaier plays an indispensable role in suppressing Twist1 expression to inhibit the Twist1/FBP1/Wnt/ß-catenin axis. Then, we verified the effect of Huaier in vitro. CONCLUSIONS: These findings suggested that Huaier granules were capable of inhibiting CCA development through regulating the Twist1/FBP1/Wnt/ß-catenin signalling axis and provided a novel orientation for the development of novel anti-CCA drugs.


Asunto(s)
Neoplasias de los Conductos Biliares , Proliferación Celular , Colangiocarcinoma , Regulación Neoplásica de la Expresión Génica , Proteínas Nucleares , Proteína 1 Relacionada con Twist , Vía de Señalización Wnt , beta Catenina , Humanos , Proteína 1 Relacionada con Twist/metabolismo , Proteína 1 Relacionada con Twist/genética , Colangiocarcinoma/metabolismo , Colangiocarcinoma/genética , Colangiocarcinoma/patología , Colangiocarcinoma/tratamiento farmacológico , Vía de Señalización Wnt/efectos de los fármacos , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Línea Celular Tumoral , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , beta Catenina/metabolismo , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética
13.
BMC Musculoskelet Disord ; 25(1): 552, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39014409

RESUMEN

BACKGROUND: To evaluate the effectiveness of a sequential internal fixation strategy and intramedullary nailing with plate augmentation (IMN/PA) for bone reconstruction in the management of infected femoral shaft defects using the Masquelet technique. METHODS: We performed a retrospective descriptive cohort study of 21 patients (mean age, 36.4 years) with infected bone defects of the femoral shaft treated by the Masquelet technique with a minimum follow-up of 18 months after second stage. After aggressive debridement, temporary stabilisation (T1) was achieved by an antibiotic-loaded bone cement spacer and internal fixation with a bone cement-coated locking plate. At second stage (T2), the spacer and the locking plate were removed following re-debridement, and IMN/PA was used as definitive fixation together with bone grafting. We evaluated the following clinical outcomes: infection recurrence, bone union time, complications, and the affected limb's knee joint function. RESULTS: The median and quartiles of bone defect length was 7 (4.75-9.5) cm. Four patients required iterative debridement for infection recurrence after T1. The median of interval between T1 and T2 was 10 (9-19) weeks. At a median follow-up of 22 (20-27.5) months, none of the patients experienced recurrence of infection. Bone union was achieved at 7 (6-8.5) months in all patients, with one patient experiencing delayed union at the distal end of bone defect due to screws loosening. At the last follow-up, the median of flexion ROM of the knee joint was 120 (105-120.0)°. CONCLUSIONS: For infected femoral shaft bone defects treated by the Masquelet technique, sequential internal fixation and IMN/PA for the reconstruction can provide excellent mechanical stability, which is beneficial for early functional exercise and bone union, and does not increase the rate of infection recurrence.


Asunto(s)
Clavos Ortopédicos , Placas Óseas , Desbridamiento , Fracturas del Fémur , Fijación Intramedular de Fracturas , Humanos , Masculino , Estudios Retrospectivos , Femenino , Adulto , Fracturas del Fémur/cirugía , Persona de Mediana Edad , Desbridamiento/métodos , Fijación Intramedular de Fracturas/métodos , Fijación Intramedular de Fracturas/instrumentación , Adulto Joven , Resultado del Tratamiento , Trasplante Óseo/métodos , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación , Estudios de Seguimiento , Cementos para Huesos/uso terapéutico , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Fémur/cirugía , Adolescente
15.
Food Chem ; 458: 140233, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38964093

RESUMEN

To analyze the effect of various drying treatments (microwave drying (MD), hot air drying (HAD), vacuum drying (VD), and vacuum freeze drying (VFD)) on taste compounds in Penaeus vannamei, relevant indicators such as free amino acids, 5'-nucleotides, and organic acids were performed. Multidimensional infrared spectroscopy (MM-IR) results found that there were notable variations in taste properties of P. vannamei. There were 18 autocorrelation peaks in 3400-900 cm-1 were screened using second-derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR). Variations in functional groups were the major contributors to taste profiles. The TAV of glutamic acid (Glu), guanine (GMP), and inosinemonphosphate (IMP) were greater than one and had notable impacts on taste profiles. VD had the highest equivalent umami value, followed by VFD, HAD, and MD. This study may provide a theoretical guide for the production of dried P. vannamei products on an industrial scale.

16.
Angew Chem Int Ed Engl ; : e202409580, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969620

RESUMEN

Herein, we propose a regional functionalization molecular design strategy that enables independent control of distinct pivotal parameters through distinct segments of the molecule. Three novel blue emitters A-BN, DA-BN, and A-DBN, have been successfully synthesized by integrating highly rigid and three-dimensional adamantane-containing spirofluorene units into the MR framework. These molecules form two distinctive functional parts: part 1 comprises a boron-nitrogen (BN)-MR framework with adjacent benzene and fluorene units forming a central luminescent core characterized by an exceptionally rigid planar geometry, allowing for narrow FWHM values; part 2 includes peripheral mesitylene, benzene, and adamantyl groups, creating a unique three-dimensional "umbrella-like" conformation to mitigate intermolecular interactions and suppress exciton annihilation. The resulting A-BN, DA-BN, and A-DBN exhibit remarkably narrow FWHM values ranging from 18 to 14 nm and near-unity photoluminescence quantum yields. Particularly, OLEDs based on DA-BN and A-DBN demonstrate outstanding efficiencies of 35.0% and 34.3%, with FWHM values as low as 22 nm and 25 nm, respectively, effectively accomplishing the integration of high color purity and high device performance.

17.
Neurol Sci ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38969961

RESUMEN

BACKGROUND: Neuromyelitis Optica Spectrum Disorder (NMOSD) is an autoimmune demyelinating disease characterized by recurrent myelitis and optic neuritis. It is associated with high rates of relapse and disability. The main treatment strategies for acute attacks include intravenous methylprednisolone pulse (IVMP) treatment and rescue treatment with plasma exchange (PLEX). Recently, the blockade of neonatal Fc receptor (FcRn)-IgG interaction has gained momentum as a therapeutic strategy. Efgartigimod, the first approved FcRn inhibitor for treating generalized myasthenia gravis, has shown impressive safety, efficacy, and tolerability, and is being regarded as "PLEX in a bottle". CASE DESCRIPTION: We report a 65-year-old female patient who was diagnosed with anti-AQP4 antibody positive NMOSD. Add-on treatment with efgartigimod to IVMP and intravenous immunoglobulin (IVIG) at the second acute relapse showed favorable results. CONCLUSION: This case suggests that efgartigimod is a potentially effective add-on therapy in acute attacks of AQP4-IgG-positive NMOSD.

18.
Talanta ; 278: 126473, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950503

RESUMEN

Tumor spheroids are widely studied for in vitro modeling of tumor growth and responses to anticancer drugs. However, current methods are mostly limited to static and perfusion-based cultures, which can be improved by more accurately mimicking pathological conditions. Here, we developed a diffusion-based dynamic culture system for tumor spheroids studies using a thin membrane of hydrogel microwells and a microfluidic device. This allows for effective exchange of nutrients and metabolites between the tumors and the culture medium flowing underneath, resulting in uniform tumor spheroids. To monitor the growth and drug response of the spheroids in real-time, we performed spectroscopic analyses of the system's impedance, demonstrating a close correlation between the tumor size and the resistance and capacitance of the system. Our results also indicate an enhanced drug effect on the tumor spheroids in the presence of a low AC electric field, suggesting a weakening mechanism of the spheroids induced by external perturbation.


Asunto(s)
Impedancia Eléctrica , Hidrogeles , Esferoides Celulares , Esferoides Celulares/metabolismo , Humanos , Hidrogeles/química , Difusión , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas/instrumentación , Membranas Artificiales , Línea Celular Tumoral
19.
Heliyon ; 10(12): e33278, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39022091

RESUMEN

Arginase, an enzyme dependent on manganese (Mn), plays a crucial role in the production of urea and processing of ammonia in the liver. Previous studies have shown that overconsumption of fructose disrupts Mn homeostasis in the liver of male mice. However, the potential sex-specific differences in the impact of fructose on hepatic Mn homeostasis remain uncertain. In this study, we provide evidence that heightened fructose intake disrupts liver Mn homeostasis in female mice. Elevated fructose exposure led to a reduction in liver Mn levels, resulting in decreased arginase and manganese superoxide dismutase (Mn-SOD) activity in the liver of female mice. The underlying mechanism involves the upregulation of carbohydrate-responsive element binding protein (ChREBP) expression and the Mn exporting gene Slc30a10 in the liver in response to fructose consumption. In summary, our findings support the involvement of fructose in liver Mn metabolism via the ChREBP/Slc30a10 pathway in female mice, and indicate that there is no disparity in the impact of fructose on hepatic Mn homeostasis between sexes.

20.
J Colloid Interface Sci ; 673: 444-452, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38878378

RESUMEN

Electrocatalytic water splitting (EWS) for hydrogen production is considered an ideal strategy for utilizing renewable energy, reducing fossil fuel consumption, and addressing environmental pollution issues. Traditional noble metal electrocatalysts have excellent performance, but their cost is high. Developing efficient, stable, and relatively inexpensive dual functional electrocatalysts is crucial for promoting large-scale EWS hydrogen production processes. Herein, a simple one-step electrodeposition method was used to grow nickel-iron phosphorus-sulfides (NiFePS) on the surface of hydrophilic treated carbon cloth (CC). The resultant NiFePS/CC with a phosphorus to sulfur ratio of 1:4 exhibited the best electrocatalytic performance, requiring only -91 mV and 216 mV overpotentials to generate the current densities of 10 mA·cm-2 in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. When it was used as a bifunctional electrocatalyst to overall water splitting (OWS), a voltage of 1.536 V can generate a current density of 10 mA·cm-2. The excellent electrocatalytic performance can be ascribed to two factors: 1) the CC with excellent conductivity serves as a growth substrate, reducing the impedance of charge transfer from the electrode to the electrolyte and accelerating the electron transfer rate; 2) The large number of ultra-thin nanosheets formed on the surface of the catalyst increase the electrochemical specific surface area, expose more reaction sites, and thus improve the electrocatalytic reaction performance. This work provides a new approach for designing efficient non-noble metal electrocatalysts for water splitting.

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