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1.
Small ; : e2406251, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39285817

RESUMEN

Rational construction of high-performance ionic conductors is a critical challenge in the field of energy storage. In this study, a series of 1D anionic titanium-based covalent organic frameworks (COFs) containing abundant alkali metal ion migration sites, namely, COF-M-R (M = Li, Na, K; R = H, Me, Et), is constructed. The integration of negative TiO6 2- sites on 1D anionic COFs allows alkali metal cations to migrate directly through the channels. Meanwhile, the π-π stacking of 1D chain-to-chain allows the distribution of ion-migration sites in 2D planes. In view of this, multidimensional ionic transport in COFs is realized to achieve high ionic conductivity. COF-M-Rs exhibit an increased ionic conductivity as the counterions change from Li+ to Na+ to K+. Notably, COF-Na-Et has an impressive ionic conductivity as high as 0.81 × 10-3 S cm-1. The different decorated groups (H, Me, and Et) on the skeleton influence the dissociation of the cation from the polyanion. This study offers deep insights into the design of COF-based solid-state electrolytes to achieve high ionic conductivity by increasing the ionic transport dimensions.

2.
Biomed Pharmacother ; 179: 117414, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260324

RESUMEN

The aim of this study is to investigate novel strategies for reducing adverse reactions caused by erdafitinib through a drug combination based on its pharmacokinetic characteristics. The spectrum and characterizations of drugs that can inhibit the metabolism of erdafitinib are examined both in vitro and in vivo. The efficacy of combination regimens are then evaluated using subcutaneous xenograft tumor models. The results demonstrated that sertraline and duloxetine, out of more than 100 screened drugs, inhibited the metabolism of erdafitinib through mixed and non-competitive inhibition, respectively. This inhibition primarily occurred via the CYP2C9 and CYP2D6 pathways. The primary alleles of CYP2C9 and CYP2D6 not only determine the metabolic characteristics of erdafitinib but also influence the strength of drug-drug interactions. Co-administration of sertraline or duloxetine with erdafitinib in rats and mice resulted in nearly a three-fold increase in the blood exposure of erdafitinib and its major metabolite M6. When sertraline or duloxetine was combined with 1/3 of the erdafitinib dosage, the anti-proliferative and pro-apoptotic effects on SNU-16 xenografts were comparable to those of the original full dose of erdafitinib. However, the combination regimen significantly mitigated hyperphosphatemia, retinal damage, intestinal villus damage, and gut microbiome dysbiosis. This study utilized pharmacokinetic methods to propose a new formulation of erdafitinib combined with sertraline or duloxetine. The findings suggest that this combination has potential for clinical co-administration based on a database analysis, thereby providing a novel strategy for anti-tumor treatment with fibroblast growth factor receptor (FGFR) inhibitors.

3.
Macromol Rapid Commun ; : e2400628, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225656

RESUMEN

The dimerization of small molecule acceptors (SMAs) holds significant potential by combining the advantages of both SMAs and polymer acceptors in realizing high power conversion efficiency (PCE) and operational stability in organic solar cells (OSCs). However, advancements in the selection and innovation of dimeric linkers are still challenging in enhancing their performance. In this study, three new dimeric acceptors, namely DY-Ar-4, DY-Ar-5, and DY-Ar-6 are synthesized, by linking two Y-series SMA subunits via an "end-to-end" strategy using flexible spacers (octyl, decyl, and dodecyl, respectively). The influence of spacer lengths on device performance is systematically investigated. The results indicate that DY-Ar-5 exhibits more compact and ordered packing, leading to an optimal morphology. OSCs based on PM6: DY-Ar-5 achieves a maximum PCE of 15.76%, attributes to enhance and balance carrier mobility, and reduce carrier recombination. This dimerization strategy using suitable non-conjugated linking units provides a rational principle for designing high-performance non-fullerene acceptors.

4.
World J Clin Cases ; 12(22): 4947-4955, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39109038

RESUMEN

BACKGROUND: Preschoolers become anxious when they are about to undergo anesthesia and surgery, warranting the development of more appropriate and effective interventions. AIM: To explore the effect of static cartoons combined with dynamic virtual environments on preoperative anxiety and anesthesia induction compliance in preschool-aged children undergoing surgery. METHODS: One hundred and sixteen preschool-aged children were selected and assigned to the drug (n = 37), intervention (n = 40), and control (n = 39) groups. All the children received routine preoperative checkups and nursing before being transferred to the preoperative preparation room on the day of the operation. The drug group received 0.5 mg/kg midazolam and the intervention group treatment consisting of static cartoons combined with dynamic virtual environments. The control group received no intervention. The modified Yale Preoperative Anxiety Scale was used to evaluate the children's anxiety level on the day before surgery (T0), before leaving the preoperative preparation room (T1), when entering the operating room (T2), and at anesthesia induction (T3). Compliance during anesthesia induction (T3) was evaluated using the Induction Compliance Checklist (ICC). Changes in mean arterial pressure (MAP), heart rate (HR), and respiratory rate (RR) were also recorded at each time point. RESULTS: The anxiety scores of the three groups increased variously at T1 and T2. At T3, both the drug and intervention groups had similar anxiety scores, both of which were lower than those in the control group. At T1 and T2, MAP, HR, and RR of the three groups increased. The drug and control groups had significantly higher MAP and RR than the intervention group at T2. At T3, the MAP, HR, and RR of the drug group decreased and were significantly lower than those in the control group but were comparable to those in the intervention group. Both the drug and intervention groups had similar ICC scores and duration of anesthesia induction (T3), both of which were higher than those of the control group. CONCLUSION: Combining static cartoons with dynamic virtual environments as effective as medication, specifically midazolam, in reducing preoperative anxiety and fear in preschool-aged children. This approach also improve their compliance during anesthesia induction and helped maintain their stable vital signs.

5.
Sci Total Environ ; 950: 175273, 2024 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-39111416

RESUMEN

Northern peatlands are important carbon pools; however, differences in the structure and function of microbiomes inhabiting contrasting geochemical zones within these peatlands have rarely been emphasized. Using 16S rRNA gene sequencing, metagenomic profiling, and detailed geochemical analyses, we investigated the taxonomic composition and genetic potential across various geochemical zones of a typical northern peatland profile in the Changbai Mountains region (Northeastern China). Specifically, we focused on elucidating the turnover of organic carbon, sulfur (S), nitrogen (N), and methane (CH4). Three geochemical zones were identified and characterized according to porewater and solid-phase analyses: the redox interface (<10 cm), shallow peat (10-100 cm), and deep peat (>100 cm). The redox interface and upper shallow peat demonstrated a high availability of labile carbon, which decreased toward deeper peat. In deep peat, anaerobic respiration and methanogenesis were likely constrained by thermodynamics, rather than solely driven by available carbon, as the acetate concentrations reached 90 µmol·L-1. Both the microbial community composition and metabolic potentials were significantly different (p < 0.05) among the redox interface, shallow peat, and deep peat. The redox interface demonstrated a close interaction between N, S, and CH4 cycling, mainly driven by Thermodesulfovibrionia, Bradyrhizobium, and Syntrophorhabdia metagenome-assembled genomes (MAGs). The archaeal Bathyarchaeia were indicated to play a significant role in the organic carbon, N, and S cycling in shallow peat. Although constrained by anaerobic respiration and methanogenesis, deep peat exhibited a higher metabolic potential for organic carbon degradation, primarily mediated by Acidobacteriota. In terms of CH4 turnover, subsurface peat (10-20 cm) was a CH4 production hotspot, with a net turnover rate of ∼2.9 nmol·cm-3·d-1, while the acetoclastic, hydrogenotrophic, and methylotrophic methanogenic pathways all potentially contributed to CH4 production. The results of this study improve our understanding of biogeochemical cycles and CH4 turnover along peatland profiles.


Asunto(s)
Metano , Microbiota , Microbiología del Suelo , China , Metano/metabolismo , Metano/análisis , ARN Ribosómico 16S , Suelo/química , Humedales , Carbono/análisis , Nitrógeno/análisis , Bacterias/clasificación , Azufre/metabolismo , Azufre/análisis , Archaea/clasificación
6.
J Am Chem Soc ; 146(34): 24016-24023, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39152917

RESUMEN

Charge transfer at heterojunction interfaces is a fundamental process that plays a crucial role in modern electronic and photonic devices. The essence of such charge transfer lies in the band offset, making charge transfer uncommon in a homojunction. Recently, sliding ferroelectricity has been proposed and confirmed in two-dimensional van der Waals stacked materials such as bilayer boron nitride. During the sliding of these layers, the band alignment shifts, creating conditions for charge separation at the interface. We employ ab initio nonadiabatic molecular dynamics simulations to elucidate the excited state carrier dynamics in bilayer boron pnictides. We propose that, akin to ferroelectric polarization flipping, the precise modulation of the distribution of excited state carriers can also be reached by sliding. Our results demonstrate that sliding induces a reversal of the frontier orbital distribution on the upper and lower layers, facilitating a robust interlayer carrier transfer. Notably, the interlayer carrier transfer is more pronounced in boron phosphide than in boron nitride, attributed to strong electron scattering in momentum space in boron nitride. We propose this novel method to manipulate carrier distribution and dynamics in a homojunction exhibiting sliding ferroelectricity, in general, paving a new way for developing advanced electronic and photonic devices.

7.
Nat Commun ; 15(1): 7150, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39168967

RESUMEN

Despite the prevalent of hexagonal, tetragonal, and triangular pore structures in two-dimensional covalent organic frameworks (2D COFs), the pentagonal pores remain conspicuously absent. We herein present the Cairo pentagonal tessellated COFs, achieved through precisely chosen geometry and metrics of the linkers, resulting in unprecedented mcm topology. In each pentagonal structure, porphyrin units create four uniform sides around 15.5 Å with 90° angles, while tetrabiphenyl unit establish a bottom edge about 11.6 Å with 120° angles, aligning precisely with the criteria of Cairo Pentagon. According to the narrow bandgap and strong near-infrared (NIR) absorbance, as-synthesized COFs exhibit the efficient singlet oxygen (1O2) generation and photothermal conversion, resulting in NIR photothermal combined photodynamic therapy to guide cancer cell apoptosis. Mechanistic studies reveal that the good 1O2 production capability upregulates intracellular lipid peroxidation, leading to glutathione depletion, low expression of glutathione peroxidase 4, and induction of ferroptosis. The implementation of pentagonal Cairo tessellations in this work provides a promising strategy for diversifying COFs with new topologies, along with multimodal NIR phototherapy.


Asunto(s)
Apoptosis , Rayos Infrarrojos , Fotoquimioterapia , Oxígeno Singlete , Humanos , Oxígeno Singlete/metabolismo , Oxígeno Singlete/química , Fotoquimioterapia/métodos , Estructuras Metalorgánicas/química , Porfirinas/química , Animales , Peroxidación de Lípido , Línea Celular Tumoral , Ferroptosis , Fototerapia/métodos , Ratones , Glutatión/química , Glutatión/metabolismo , Fármacos Fotosensibilizantes/química , Neoplasias/terapia , Neoplasias/metabolismo
8.
Int J Biol Macromol ; 278(Pt 4): 134840, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39217040

RESUMEN

Hen egg low-density lipoprotein (heLDL), as alternative of serum-derived LDL, was used as drug delivery system of ceftiofur (CEF). The CEF-loaded hen egg low-density lipoprotein (CEF-heLDL) with complete apolipoprotein structure and high drug loading rate was synthesized, possesses suitable particle size. CEF-heLDL undergoes cellular uptake and colocalizes with lysosomes in vitro. An intracellular infection model of the bovine endometrial epithelial cells and a coeliac-induced inflammation model of mice by Staphylococcus aureus (S. aureus) were established, and significantly lower intracellular S. aureus levels of CEF-heLDL group than CEF-free group (P < 0.001) was observed. The antibacterial efficacy was sustained for 24 h. Up to 400 mg/kg of CEF-heLDL, 20 times the clinical practice, were intraperitoneally administrated, and no significant toxicity signs on mice were observed. HeLDLs is an effective, safe, and cheap drug carrier, and could also be used for transmembrane delivering other antibiotics.


Asunto(s)
Antibacterianos , Cefalosporinas , Pollos , Lipoproteínas LDL , Staphylococcus aureus , Animales , Staphylococcus aureus/efectos de los fármacos , Lipoproteínas LDL/metabolismo , Antibacterianos/farmacología , Antibacterianos/química , Ratones , Cefalosporinas/farmacología , Cefalosporinas/farmacocinética , Cefalosporinas/química , Bovinos , Femenino , Portadores de Fármacos/química , Infecciones Estafilocócicas/tratamiento farmacológico , Huevos
9.
Heliyon ; 10(15): e34723, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39144951

RESUMEN

Objective: To validate the feasibility of ultrasound in assessing the curative effect of botulinum toxin type A (BTXA) in treating hypertrophic scar (HS). Methods: Eight healthy New Zealand long-eared rabbits were utilized in the study. Four wounds, each measuring 1.0 cm in diameter, were created on both ears of each rabbit. Immediately after surgery, each of these wounds received an injection containing a distinct concentration of BTXA. On postoperative week 6, scar thickness, vascularity, and hardness were assessed based on high frequency ultrasound (HFUS), superb microvascular imaging (SMI), shear wave elastography (SWE), Masson staining, and immunohistochemical staining for CD31. Results: All wounds healed well, and HSs formed after 6 weeks post-surgery. Scar thickness based on HFUS presented a significant decrease with increasing BTXA concentration (p < 0.05), aligning with the gross morphology. Simultaneously, scar stiffness, evaluated using SWE, showed a significant decrease in accordance with the variation of the collagen volume fraction, which refers to the ratio of the collagen positive area to the total area (p < 0.05). Although the vascularity index obtained by SMI did not exhibit a statistically significant change across different BTXA concentrations, this technique effectively illustrated the microvascular perfusion in HS. Immunohistochemical staining for CD31 revealed that BTXA inhibited angiogenesis. Conclusion: HFUS and SWE displayed excellent performance in evaluating HS thickness and stiffness. SMI showed a good performance in reflecting microvascular signals in HS. These ultrasound techniques have great potential in assessing the therapeutic effect of BTXA in HS.

10.
Angew Chem Int Ed Engl ; : e202412890, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39148428

RESUMEN

The design of three-dimensional covalent organic frameworks (3D COFs) using linear and trigonal linkers remains challenging due to the difficulty in achieving a specific non-planar spatial arrangement with low-connectivity building units. Here, we report the novel 3D COFs with linear and trigonal linkers, termed TMB-COFs, exhibiting srs topology. The steric hindrance provides an additional force to alter the torsion angles of peripheral triangular units, guiding the linear unit to connect with the trigonal unit into 3D srs frameworks, rather than the more commonly observed two-dimensional (2D) hcb structures. Furthermore, we comprehensively examined the hydrogen peroxide photocatalytic production capacity of the TMB-COFs in comparison with analogous 2D COFs. The experimental results and DFT calculations demonstrate a significant enhancement in photocatalytic hydrogen peroxide production efficacy through framework regulation. This work emphasizes the steric configuration using low connectivity building units, offering a fresh perspective on the design and application of 3D COFs.

11.
ACS Appl Mater Interfaces ; 16(36): 48386-48394, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39205497

RESUMEN

Melioration of the through-plane thermal conductivity (TC) of thermal interface materials (TIMs) is a sore need for efficient heat dissipation to handle an overheating concern of high-power-density electronics. Herein, we constructed a snail shell-like thermal conductive framework to facilitate vertical heat conduction in TIMs. With inspiration from spirally growing calcium carbonate platelets of snail shells, a facile double-microrod-assisted curliness method was developed to spirally coil boron nitride nanosheet (BNNS)/aramid nanofiber (ANF) laminates where interconnected BNNSs lie along the horizontal plane. Thus, vertical alignment of BNNSs in the resultant TIM was achieved, exhibiting a through-plane TC enhancement of ∼100% compared to the counterpart with randomly distributed BNNSs at the same BNNS addition (50 wt %). The Foygel's nonlinear model revealed that this unique snail shell-like BNNS framework reduced interfacial thermal resistance by 4 orders of magnitude. Our TIM showed superior interfacial thermal dissipation efficiency, leading to a temperature reduction of 42.6 °C for the LED chip compared to the aforementioned counterpart. Our work paves a valuable way for fabricating high-performance TIMs to ensure reliable operation of electrical devices.

13.
Chempluschem ; : e202400069, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955991

RESUMEN

Covalent organic frameworks (COFs) are an innovative class of crystalline porous polymers composed of light elements such as C, N, O, etc., linked by covalent bonds. The distinctive properties of COFs, including designable building blocks, large specific surface area, tunable pore size, abundant active sites, and remarkable stability, have led their widespread applications in electrocatalysis. In recent years, COF-based electrocatalysts have made remarkable progress in various electrocatalytic fields, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, nitrogen reduction reaction, nitrate reduction reaction, and carbon dioxide reduction reaction. This review begins with an introduction to the design and synthesis strategies employed for COF-based electrocatalysts. These strategies include heteroatom doping, metalation of COF and building monomers, encapsulation of active sites within COF pores, and the development of COF-based derived materials. Subsequently, a systematic overview of the recent advancements in the application of COF-based catalysts in electrocatalysis is presented. Finally, the review discusses the main challenges and outlines possible avenues for the future development of COF-based electrocatalysts.

14.
Zhongguo Zhong Yao Za Zhi ; 49(11): 2889-2896, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39041148

RESUMEN

To determine the optimal harvesting period and rational medicinal parts of Zanthoxylum nitidum, the main effective components of cultivated Z. nitidum samples, which originate from various growth years, harvesting months, and different parts were analyzed and compared with the wild samples. HPLC was performed on a Kinetex C18 column(4. 6 mm×100 mm, 2. 6 µm) with the gradient elution of 0. 3% phosphoric acid solution-acetonitrile(80 ∶ 20) containing 0. 2% triethylamine. The flow rate was 1. 0 m L·min-1, and the detection wavelength was 273 nm. The column temperature was 30 ℃. Nitidine chloride and chelerythrine, the main effective components, were determined as the markers. The results showed there was no significant difference in the contents of the main effective components among the roots of wild and cultivated Z. nitidum, as well as the roots and roots + stems of cultivated Z. nitidum. The statistical results of HCA and PCA indicated that the roots and stems could be clearly distinguished, but no distinction could be made between wild and cultivated products, which was consistent with the results of the significance analysis. The total contents of nitidine chloride and chelerythrine in roots and stems of Z. nitidum of 1-6 years old were 0. 114%-0. 256% and 0. 030%-0. 133%, respectively. These results suggested a positive correlation between the content of the main effective components and the growth years. No significant difference was observed between the contents of samples harvested in different seasons, indicating that the harvest season had no effect on the content of the main effective components of the Z. nitidum samples. The total contents of nitidine chloride and chelerythrine of the dried Z. nitidum samples(excluding branches) from three plantation bases were 0. 308%±0. 123% in Yunfu, 0. 192%±0. 025% in Maoming, and 0. 197%±0. 052% in Nanning, respectively, and they were all not less than 0. 15%, or in other words, the roots(including fibrous roots, taproots, and underground stems) and stems(aboveground stems) of Z. nitidum transplanted for more than 2. 5 years can meet the medical requirements. This study demonstrates that the cultivated Z. nitidum could be used as a valid substitute for the wild Z. nitidum, which provides a guarantee for the sustainable development and the application of Z. nitidum resources. The stems and roots could be considered medicinal parts of Z. nitidum. It is recommended to revise the medicinal parts of Z. nitidum to dried roots and stems in the next edition of Chinese Pharmacopoeia, and the medicinal parts can be harvested all year round. In order to ensure the content of effective components and clinical effectiveness, the root and stem should be harvested for medical use after the seedlings of Z. nitidum have been transplanted for more than three years.


Asunto(s)
Benzofenantridinas , Medicamentos Herbarios Chinos , Zanthoxylum , Zanthoxylum/química , Zanthoxylum/crecimiento & desarrollo , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Cromatografía Líquida de Alta Presión , Benzofenantridinas/análisis , Benzofenantridinas/química , Raíces de Plantas/química , Raíces de Plantas/crecimiento & desarrollo , Tallos de la Planta/química , Tallos de la Planta/crecimiento & desarrollo
15.
J Am Chem Soc ; 146(29): 20312-20322, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38980945

RESUMEN

Organic photovoltaic (OPV) devices attain high performance with nonfullerene acceptors by utilizing the synergistic dual channels of charge generation that originate from excitations in both the donor and acceptor materials. However, the specific intermediate states that facilitate both channels are subject to debate. To address this issue, we employ time-resolved terahertz spectroscopy with improved sensitivity (ΔE/E < 10-6), enabling direct probing of charge generation dynamics in a prototypical PM6:Y6 bulk heterojunction system under one-sun-equivalent excitation density. Charge generation arising from donor excitations is characterized with a rise time of ∼9 ps, while that from acceptor excitations shows a rise time of ∼18 ps. Temperature-dependent measurements further reveal notably distinct activation energies for these two charge generation pathways. Additionally, the two channels of charge generation can be substantially manipulated by altering the ratio of bulk to interfaces. These findings strongly suggest the presence of two distinct intermediate states: interfacial and intramoiety excitations. These states are crucial in mediating the transfer of electrons and holes, driving charge generation within OPV devices.

16.
Oncologist ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38990195

RESUMEN

BACKGROUND: Encouraging antitumor activity of nab-paclitaxel plus S-1 (AS) has been shown in several small-scale studies. This study compared the efficacy and safety of AS versus standard-of-care nab-paclitaxel plus gemcitabine (AG) as a first-line treatment for advanced pancreatic cancer (PC). METHODS: In this multicenter, randomized, phase II trial, eligible patients with unresectable, locally advanced, or metastatic PC were recruited and randomly assigned (1:1) to receive AS (nab-paclitaxel 125 mg/m2 on days 1 and 8; S-1 twice daily on days 1 through 14) or AG (nab-paclitaxel 125 mg/m2 on days 1 and 8; gemcitabine 1000 mg/m2 on days 1 and 8) for 6 cycles. The primary endpoint was progression-free survival (PFS). RESULTS: Between July 16, 2019, and September 9, 2022, 62 patients (AS, n = 32; AG, n = 30) were treated and evaluated. With a median follow-up of 8.36 months at preplanned interim analysis (data cutoff, March 24, 2023), the median PFS (8.48 vs 4.47 months; hazard ratio [HR], 0.402; P = .002) and overall survival (OS; 13.73 vs 9.59 months; HR, 0.226; P < .001) in the AS group were significantly longer compared to the AG group. More patients had objective response in the AS group than AG group (37.50% vs 6.67%; P = .005). The most common grade 3-4 adverse events were neutropenia and leucopenia in both groups, and gamma glutamyl transferase increase was observed only in the AG group. CONCLUSION: The first-line AS regimen significantly extended both PFS and OS of Chinese patients with advanced PC when compared with the AG regimen, with a comparable safety profile. (ClinicalTrials.gov Identifier: NCT03636308).

17.
Sci Rep ; 14(1): 16315, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39009661

RESUMEN

In this article, we investigated the solitary wave solutions of the KdV-mKdV equation using Hirota's bilinear method. Closed-form analytical single and multiple solitary wave solutions were obtained. Through qualitative methods and the analysis of solitary waveforms, we discovered that in addition to sech-type solitary waves, the system also contains Sech 2 -type solitary waves. By employing the trial functions method, we obtained a single Sech 2 -type solitary wave and verified its existence and stability using the split-Step Fourier Transform method. Furthermore, we use the collision of two Sech 2 -type single solitary waves to excite a stable Sech 2 -type double solitary wave. Similarly, we excite a stable triple solitary wave with three Sech 2 -type single solitary waves. This method can also be used to excite stable multiple solitary waves. It is shown that these solitary wave solutions enrich the dynamic behavior of the KdV-mKdV equation and provide methods for solving Sech 2 -type solitary waves, which hold significant theoretical value.

18.
Sci Rep ; 14(1): 15107, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956066

RESUMEN

Ferroptosis is an iron-dependent cell death form characterized by reactive oxygen species (ROS) overgeneration and lipid peroxidation. Myricetin, a flavonoid that exists in numerous plants, exhibits potent antioxidant capacity. Given that iron accumulation and ROS-provoked dopaminergic neuron death are the two main pathological hallmarks of Parkinson's disease (PD), we aimed to investigate whether myricetin decreases neuronal death through suppressing ferroptosis. The PD models were established by intraperitoneally injecting 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) into rats and by treating SH-SY5Y cells with 1-methyl-4-phenylpyridinium (MPP+), respectively. Ferroptosis was identified by assessing the levels of Fe2+, ROS, malondialdehyde (MDA), and glutathione (GSH). The results demonstrated that myricetin treatment effectively mitigated MPTP-triggered motor impairment, dopamine neuronal death, and α-synuclein (α-Syn) accumulation in PD models. Myricetin also alleviated MPTP-induced ferroptosis, as evidenced by decreased levels of Fe2+, ROS, and MDA and increased levels of GSH in the substantia nigra (SN) and serum in PD models. All these changes were reversed by erastin, a ferroptosis activator. In vitro, myricetin treatment restored SH-SY5Y cell viability and alleviated MPP+-induced SH-SY5Y cell ferroptosis. Mechanistically, myricetin accelerated nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and subsequent glutathione peroxidase 4 (Gpx4) expression in MPP+-treated SH-SY5Y cells, two critical inhibitors of ferroptosis. Collectively, these data demonstrate that myricetin may be a potential agent for decreasing dopaminergic neuron death by inhibiting ferroptosis in PD.


Asunto(s)
Modelos Animales de Enfermedad , Neuronas Dopaminérgicas , Ferroptosis , Flavonoides , Especies Reactivas de Oxígeno , Ferroptosis/efectos de los fármacos , Animales , Flavonoides/farmacología , Ratas , Masculino , Especies Reactivas de Oxígeno/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Humanos , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Línea Celular Tumoral , Hierro/metabolismo , alfa-Sinucleína/metabolismo , Ratas Sprague-Dawley , Glutatión/metabolismo , Peroxidación de Lípido/efectos de los fármacos , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/efectos adversos , Factor 2 Relacionado con NF-E2/metabolismo
19.
Small ; : e2402655, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949408

RESUMEN

Solution Gated Graphene Field-Effect Transistors (SGGT) are eagerly anticipated as an amplification platform for fabricating advanced ultra-sensitive sensors, allowing significant modulation of the drain current with minimal gate voltage. However, few studies have focused on light-matter interplay gating control for SGGT. Herein, this challenge is addressed by creating an innovative photoelectrochemical solution-gated graphene field-effect transistor (PEC-SGGT) functionalized with enzyme cascade reactions (ECR) for Organophosphorus (OPs) detection. The ECR system, consisting of acetylcholinesterase (AChE) and CuBTC nanomimetic enzymes, selectively recognizes OPs and forms o-phenylenediamine (oPD) oligomers sediment on the PEC electrode, with layer thickness related to the OPs concentration, demonstrating time-integrated amplification. Under light stimulation, the additional photovoltage generated on the PEC gate electrode is influenced by the oPD oligomers sediment layer, creating a differentiated voltage distribution along the gate path. PEC-SGGT, inherently equipped with built-in amplification circuits, sensitively captures gate voltage changes and delivers output with an impressive thousandfold current gain. The seamless integration of these three amplification modes in this advanced sensor allows a good linear range and highly sensitive detection of OPs, with a detection limit as low as 0.05 pm. This work provides a proof-of-concept for the feasibility of light-assisted functionalized gate-controlled PEC-SGGT for small molecule detection.

20.
World J Diabetes ; 15(6): 1317-1339, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38983802

RESUMEN

BACKGROUND: Diabetic retinopathy (DR) is the primary cause of visual problems in patients with diabetes. The Heyingwuzi formulation (HYWZF) is effective against DR. AIM: To determine the HYWZF prevention mechanisms, especially those underlying mitophagy. METHODS: Human retinal capillary endothelial cells (HRCECs) were treated with high glucose (hg), HYWZF serum, PX-478, or Mdivi-1 in vitro. Then, cell counting kit-8, transwell, and tube formation assays were used to evaluate HRCEC proliferation, invasion, and tube formation, respectively. Transmission electron microscopy was used to assess mitochondrial morphology, and Western blotting was used to determine the protein levels. Flow cytometry was used to assess cell apoptosis, reactive oxygen species (ROS) production, and mitochondrial membrane potential. Moreover, C57BL/6 mice were established in vivo using streptozotocin and treated with HYWZF for four weeks. Blood glucose levels and body weight were monitored continuously. Changes in retinal characteristics were evaluated using hematoxylin and eosin, tar violet, and periodic acid-Schiff staining. Protein levels in retinal tissues were determined via Western blotting, immunohistochemistry, and immunostaining. RESULTS: HYWZF inhibited excessive ROS production, apoptosis, tube formation, and invasion in hg-induced HRCECs via mitochondrial autophagy in vitro. It increased the mRNA expression levels of BCL2-interacting protein 3 (BNIP3), FUN14 domain-containing 1, BNIP3-like (BNIP3L, also known as NIX), PARKIN, PTEN-induced kinase 1, and hypoxia-inducible factor (HIF)-1α. Moreover, it downregulated the protein levels of vascular endothelial cell growth factor and increased the light chain 3-II/I ratio. However, PX-478 and Mdivi-1 reversed these effects. Additionally, PX-478 and Mdivi-1 rescued the effects of HYWZF by decreasing oxidative stress and apoptosis and increasing mitophagy. HYWZF intervention improved the symptoms of diabetes, tissue damage, number of acellular capillaries, and oxidative stress in vivo. Furthermore, in vivo experiments confirmed the results of in vitro experiments. CONCLUSION: HYWZF alleviated DR and associated damage by promoting mitophagy via the HIF-1α/BNIP3/NIX axis.

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