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1.
Curr Med Sci ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967891

RESUMO

OBJECTIVE: Obesity-induced kidney injury contributes to the development of diabetic nephropathy (DN). Here, we identified the functions of ubiquitin-specific peptidase 19 (USP19) in HK-2 cells exposed to a combination of high glucose (HG) and free fatty acid (FFA) and determined its association with TGF-beta-activated kinase 1 (TAK1). METHODS: HK-2 cells were exposed to a combination of HG and FFA. USP19 mRNA expression was detected by quantitative RT-PCR (qRT-PCR), and protein analysis was performed by immunoblotting (IB). Cell growth was assessed by Cell Counting Kit-8 (CCK-8) viability and 5-ethynyl-2'-deoxyuridine (EdU) proliferation assays. Cell cycle distribution and apoptosis were detected by flow cytometry. The USP19/TAK1 interaction and ubiquitinated TAK1 levels were assayed by coimmunoprecipitation (Co-IP) assays and IB. RESULTS: In HG+FFA-challenged HK-2 cells, USP19 was highly expressed. USP19 knockdown attenuated HG+FFA-triggered growth inhibition and apoptosis promotion in HK-2 cells. Moreover, USP19 knockdown alleviated HG+FFA-mediated PTEN-induced putative kinase 1 (PINK1)/Parkin pathway inactivation and increased mitochondrial reactive oxygen species (ROS) generation in HK-2 cells. Mechanistically, USP19 stabilized the TAK1 protein through deubiquitination. Importantly, increased TAK1 expression reversed the USP19 knockdown-mediated phenotypic changes and PINK1/Parkin pathway activation in HG+FFA-challenged HK-2 cells. CONCLUSION: The findings revealed that USP19 plays a crucial role in promoting HK-2 cell dysfunction induced by combined stimulation with HG and FFAs by stabilizing TAK1, providing a potential therapeutic strategy for combating DN.

2.
Child Dev ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39032033

RESUMO

Reading disability (RD) may be characterized by reduced print-speech convergence, which is the extent to which neurocognitive processes for reading and hearing words overlap. We examined how print-speech convergence changes from children (mean age: 11.07+0.48) to adults (mean age: 21.33+1.80) in 86 readers with or without RD. The participants were recruited in elementary schools and associate degree colleges in China (from 2020 to 2021). Three patterns of abnormalities were revealed: (1) persistent reduction of print-speech convergence in the left inferior parietal cortex in both children and adults with RD, suggesting a neural signature of RD; (2) reduction of print-speech convergence in the left inferior frontal gyrus only evident in children but not adults with RD, suggesting a developmental delay; and (3) increased print-speech convergence in adults with RD than typical adults in the bilateral cerebella/fusiform, suggesting compensations. It provides insights into developmental differences in brain functional abnormalities in RD.

3.
J Chromatogr A ; 1729: 465040, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38838450

RESUMO

In this work, porous polyimide microfibers (PI-µF) were prepared by high-pressure wet spinning method, and successfully applied as adsorbents for solid phase extraction (SPE) of fluoroquinolones (FQs) in water and food samples. The PI-µFs of ∼10, 25, 50, 100 µm in diameter could be controlled by the inner diameter of quartz capillary nozzles. The flow resistance of SPE cartridges packed with 10 µm PI microfiber (10-PI-µF) and 25-PI-µF was comparable to or even lower than that of commercial SPE cartridges, while the flow resistance of 50-PI-µF and 100-PI-µF SPE cartridges was increased obviously due to tiny broken pieces. The 10-PI-µF and 25-PI-µF have a specific surface area of 102 m2 g-1 and 76 m2 g-1, mesopores of 22-32 nm, and large breakthrough volume of 110 mL/5 mg and 85 mL/5 mg for FQs, while the 50-PI-µF and 100-PI-µF had much lower specific surface area and hardly had retention for FQs. FQs from tap water, egg and milk samples were then extracted by PI-µF SPE, and analyzed by high performance liquid chromatography-fluorescence detector (HPLC-FLD). SPE parameters as type of elution solvent, elution solvent volume, pH value of sample solution, flow rate of sample solution, and breakthrough volume were first optimized in detail. Under the optimal conditions, the PI-µF SPE/HPLC-FLD method showed high recoveries (96.8%-107%), wide linearity (0.05-50 µg L-1, or 0.01-10 µg L-1), high determination coefficients (R2 ≥0.9992), and low limits of detection (LODs, 0.005-0.014 µg L-1). For the real tap water, egg and milk samples, the recoveries and RSDs were 81-119% and 0.8-9.8%, respectively. The results show that porous microfiber up to 25 µm in diameter is a promising solid-phase extraction adsorbent with the lowest flow resistance that can be used for trace organic pollutants in water and food samples.


Assuntos
Fluoroquinolonas , Limite de Detecção , Leite , Extração em Fase Sólida , Poluentes Químicos da Água , Extração em Fase Sólida/métodos , Fluoroquinolonas/análise , Fluoroquinolonas/isolamento & purificação , Fluoroquinolonas/química , Porosidade , Leite/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/química , Cromatografia Líquida de Alta Pressão/métodos , Animais , Ovos/análise , Adsorção , Pressão , Contaminação de Alimentos/análise , Resinas Sintéticas/química , Análise de Alimentos/métodos , Reprodutibilidade dos Testes
4.
Neuropsychologia ; 201: 108935, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-38848989

RESUMO

Different tasks have been used in examining the neural functional differences associated with developmental dyslexia (DD), and consequently, different findings have been reported. However, very few studies have systematically compared multiple tasks in understanding what specific task differences each brain region is associated with. In this study, we employed an auditory rhyming task, a visual rhyming task, and a visual spelling task, in order to investigate shared and task-specific neural differences in Chinese children with DD. First, we found that children with DD had reduced activation in the opercular part of the left inferior frontal gyrus (IFG) only in the two rhyming tasks, suggesting impaired phonological analysis. Children with DD showed functional differences in the right lingual gyrus/inferior occipital gyrus only in the two visual tasks, suggesting deficiency in their visuo-orthographic processing. Moreover, children with DD showed reduced activation in the left dorsal inferior frontal gyrus and increased activation in the right precentral gyrus across all of the three tasks, suggesting neural signatures of DD in Chinese. In summary, our study successfully separated brain regions associated with differences in orthographic processing, phonological processing, and general lexical processing in DD. It advances our understanding about the neural mechanisms of DD.


Assuntos
Mapeamento Encefálico , Encéfalo , Dislexia , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Criança , Dislexia/fisiopatologia , Dislexia/diagnóstico por imagem , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Leitura
5.
Adv Sci (Weinh) ; : e2401635, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828658

RESUMO

The low mechanical reliability and integration failure are key challenges hindering the commercialization of geometrically flexible batteries. This work proposes that the failure of directly integrating flexible batteries using traditional rigid adhesives is primarily due to the mismatch between the generated stress at the adhesive/substrate interface, and the maximum allowable stress. Accordingly, a stress redistribution adhesive layer (SRAL) strategy is conceived by using elastic adhesive to redistribute the generated stress. The function mechanism of the SRAL strategy is confirmed by theoretical finite element analysis. Experimentally, a polyurethane (PU) type elastic adhesive (with maximum strain of 1425%) is synthesized and used as the SRAL to integrate rigid cells on different flexible substrates to fabricate directly integrated flexible battery with robust output under various harsh environments, such as stretching, twisting, and even bending in water. The SRAL strategy is expected to be generally applicable in various flexible devices that involve the integration of rigid components onto flexible substrates.

6.
J Phys Chem Lett ; 15(19): 5223-5230, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38717392

RESUMO

In the anodic catalyst layer of a proton-exchange membrane (PEM) water electrolyzer, the triple-phase boundary (TPB) is mainly distributed on the surface of ultrafine iridium-based catalysts encapsulated by the ionomer within the catalyst-ionomer agglomerate. It is found that the ionomer at the TPB acts as a barrier to mass transport and a buffer for the bubble coverage during the oxygen evolution reaction (OER). The barrier effect can decrease the OER performance of the catalysts inside the agglomerate by ≤23%, while the buffer effect can separate the bubble evolution sites from the OER sites, turning the instant deactivation caused by the bubble coverage into a gradual performance loss caused by local water starvation. However, this local water starvation still deteriorates the catalyst performance because of the affinity of the ionomer surface for bubbles. Introducing additional transport paths into the agglomerate can reduce the barrier effect and regulate the bubble behavior, reducing the overpotential by 0.308 V at 5 A cm-2.

7.
Microb Cell Fact ; 23(1): 128, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704580

RESUMO

BACKGROUND: Anthraquinone-fused enediynes (AFEs) are excellent payloads for antibody-drug conjugates (ADCs). The yields of AFEs in the original bacterial hosts are extremely low. Multiple traditional methods had been adopted to enhance the production of the AFEs. Despite these efforts, the production titers of these compounds are still low, presenting a practical challenge for their development. Tiancimycins (TNMs) are a class of AFEs produced by Streptomyces sp. CB03234. One of their salient features is that they exhibit rapid and complete cell killing ability against various cancer cell lines. RESULTS: In this study, a combinatorial metabolic engineering strategy guided by the CB03234-S genome and transcriptome was employed to improve the titers of TNMs. First, re-sequencing of CB03234-S (Ribosome engineered mutant strains) genome revealed the deletion of a 583-kb DNA fragment, accounting for about 7.5% of its genome. Second, by individual or combined inactivation of seven potential precursor competitive biosynthetic gene clusters (BGCs) in CB03234-S, a double-BGC inactivation mutant, S1009, was identified with an improved TNMs titer of 28.2 ± 0.8 mg/L. Third, overexpression of five essential biosynthetic genes, including two post-modification genes, and three self-resistance auxiliary genes, was also conducted, through which we discovered that mutants carrying the core genes, tnmE or tnmE10, exhibited enhanced TNMs production. The average TNMs yield reached 43.5 ± 2.4 mg/L in a 30-L fermenter, representing an approximately 360% increase over CB03234-S and the highest titer among all AFEs to date. Moreover, the resulting mutant produced TNM-W, a unique TNM derivative with a double bond instead of a common ethylene oxide moiety. Preliminary studies suggested that TNM-W was probably converted from TNM-A by both TnmE and TnmE10. CONCLUSIONS: Based on the genome and transcriptome analyses, we adopted a combined metabolic engineering strategy for precursor enrichment and biosynthetic pathway reorganization to construct a high-yield strain of TNMs based on CB03234-S. Our study establishes a solid basis for the clinical development of AFE-based ADCs.


Assuntos
Antraquinonas , Enedi-Inos , Engenharia Metabólica , Streptomyces , Streptomyces/metabolismo , Streptomyces/genética , Engenharia Metabólica/métodos , Antraquinonas/metabolismo , Enedi-Inos/metabolismo , Família Multigênica , Vias Biossintéticas
8.
Int J Biol Macromol ; 271(Pt 1): 132241, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38768916

RESUMO

The abnormal uric acid (UA) level in urine can serve as warning signals of many diseases, such as gout and metabolic cardiovascular diseases. The current methods for detecting UA face limitations of instrument dependence and the requirement for non-invasiveness, making it challenging to fulfill the need for home-based application. In this study, we designed an aptasensor that combined UA-specific transcriptional regulation and a fluorescent RNA aptamer for convenient urinary UA testing. The concentration of UA can be translated into the intensity of fluorescent signals. The aptasensor showed higher sensitivity and more robust anti-interference performance. UA levels in the urine of different volunteers could be accurately tested using this method. In addition, a paper-based aptasensor for UA self-testing was manufactured, in which the urinary UA levels could be determined using a smartphone-based colorimetric approach. This work not only demonstrates a new approach for the design of disease-associated aptasensor, but also offers promising ideas for home-based detection of UA.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Papel , Ácido Úrico , Ácido Úrico/urina , Humanos , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Autoteste , Colorimetria/métodos , Transcrição Gênica , Urinálise/métodos , Urinálise/instrumentação
9.
Dalton Trans ; 53(23): 9819-9826, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38787742

RESUMO

An AA'3B4O12-type perovskite oxide PbMn3(CrMn3)O12 was synthesized by high-pressure solid-state reactions at 8 GPa and 1373 K. Synchrotron X-ray diffraction shows a cubic crystal structure with the space group Im3̄. The charge states are verified by X-ray photoelectron spectroscopy to be PbMn3+3(Cr3+Mn3+2Mn4+)O12, where the Pb2+ and Mn3+ are 1 : 3 ordered respectively at A and A' sites, while the Cr3+, Mn3+ and Mn4+ are disorderly distributed at the B site. PbMn3(CrMn3)O12 features a long-range antiferromagnetic order of A'-site Mn3+ spins at about 66 K and a subsequent spin glass transition around 36 K due to the randomly distributed Cr3+, Mn3+, and Mn4+ cations at the B site. This unique stepwise order of A' and B-site spins indicates weak A'-B site spin interactions, which are dominated by the difference in the B-site Mn3+/Ni2+ and Mn4+ number in the quadruple perovskites AMn3B4O12.

10.
Neuroepidemiology ; : 1-12, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749405

RESUMO

INTRODUCTION: The contribution of individual and combined inflammatory markers for the prognosis of acute ischemic stroke (AIS) remains elusive. This study investigated the effect of systemic inflammatory response index (SIRI), and neutrophil to high-density lipoprotein ratio (NHR), which is mediated by fasting blood glucose (FBG), on 90-day prognosis of patients with AIS. METHODS: In this pre-specified substudy of an observational cohort study, 2,828 patients with AIS were enrolled from the Nanjing Stroke Registry between January 2017 and July 2021. Peripheral venous blood was collected from patients fasting for at least 8 h within 24 h of admission to gather information on the following parameters: neutrophil count, lymphocyte count, monocyte count, HDL level, and fasting blood glucose level. Then, the SIRI and NHR values were calculated. Following this, the correlation among SIRI, NHR, and modified Rankin Scale (mRS) scores 90 days after onset was examined via univariate and multivariate logistic analyses. Lastly, mediation analysis was performed to examine the relationship between systematic inflammatory response and study outcomes mediated by FBG. RESULTS: SIRI and NHR were both negatively correlated with clinical outcomes (p < 0.05). Logistic regression analysis revealed that SIRI and NHR were independently associated with poor outcomes after adjusting for potential confounders. Subgroup analyses further validated these correlations. Meanwhile, mediation analysis corroborated that FBG partially mediated the associations between SIRI and a poor prognosis at 90 days (indirect effect estimate = 0.0038, bootstrap 95% CI 0.001-0.008; direct effect estimate = 0.1719, bootstrap 95% CI 0.1258-0.2179). Besides, FBG also played a mediating role between NHR and poor outcomes (indirect effect estimate = 0.0066, bootstrap 95% CI 0.002-0.120; direct effect estimate = 0.1308, bootstrap 95% CI 0.0934-0.1681). CONCLUSION: Our study demonstrated that SIRI and NHR are positively associated with poor clinical and mortality outcomes at 90 days in AIS patients, which was partially mediated by FBG.

11.
Angew Chem Int Ed Engl ; 63(30): e202404374, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38726699

RESUMO

Strategies for discovery of high-performance electrocatalysts are important to advance clean energy technologies. Metastable phases such as low temperature or interfacial structures that are difficult to access in bulk may offer such catalytically active surfaces. We report here that the suboxide Zr3O, which is formed at Zr-ZrO2 interfaces but does not appear in the experimental Zr-O phase diagram exhibits outstanding oxygen reduction reaction (ORR) performance surpassing that of benchmark Pt/C and most transition metal-based catalysts. Addition of Fe3C nanoparticles to give a Zr-Zr3O-Fe3C/NC catalyst (NC=nitrogen-doped carbon) gives a half-wave potential (E1/2) of 0.914 V, outperforming Pt/C and showing only a 3 mV decrease after 20,000 electrochemical cycles. A zinc-air battery (ZAB) using this cathode material has a high power density of 241.1 mW cm-2 and remains stable for over 50 days of continuous cycling, demonstrating potential for practical applications. Zr3O demonstrates that interfacial or other phases that are difficult to stabilize may offer new directions for the discovery of high-performance electrocatalysts.

12.
ACS Omega ; 9(14): 15818-15832, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617642

RESUMO

How to realize efficient treatment of coal slime generated by a coal washing operation is an urgent problem to be solved in this industry. The presence of clay minerals, especially highly hydrophilic montmorillonite (MMT), is the key to the poor treatment effect of coal slime. Polyacrylamide (PAM) is very popular as a polymer agent to improve the treatment of coal slime. However, when it is used to treat coal slime with a high content of MMT, the selection of PAM type and the mechanism of action are still lacking. In this study, the effects of different types of PAM on the treatment of coal slime water containing MMT are considered by sedimentation and press filtration tests. The interaction mechanism of PAM on the MMT surface is studied by using ζ-potential, Brunauer-Emmett-Teller (BET) analysis, low-field nuclear magnetic resonance, density functional theory (DFT), and molecular dynamics (MD) simulations. The results show that the three PAM can improve the sedimentation and filtration effect of coal slime water, and the performance is CPAM > NPAM > APAM. The ζ-potential of the MMT (001) surface increases under the action of three PAM, and the effect of CPAM is the most significant. The adsorption of PAM on the MMT (001) surface has the ability to neutralize the surface charge of MMT. The flocculation of MMT particles under PAM results in an increase of particle size and a decrease of specific surface area. Meanwhile, the pore volume of MMT decreases, and the average pore size increases. In addition, PAM mainly removes vicinal water on the MMT surface. The active sites of the MMT surface and PAM are calculated by DFT. The adsorption of three PAM structural units on the MMT Na-001 surface and non-001 surface is nonbonding interaction, and the adsorption energy of CPAM is the largest. And the left shift of εp of the O atom on the MMT surface is conducive to the stable adsorption of CPAM. The MD results show that the concentration of water molecules on the surface of MMT Na-001 decreases after PAM is adsorbed on the MMT Na-001 surface, indicating that PAM can keep water molecules away from the surface of MMT, which means that the hydrophobicity of the MMT surface is enhanced. This study has guiding significance for the selection of PAM and the development of new flocculants in the treatment of coal slime with a high content of MMT.

13.
Beilstein J Org Chem ; 20: 741-752, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633914

RESUMO

Crocins are water-soluble apocarotenoids isolated from the flowers of crocus and gardenia. They exhibit various pharmacological effects, including neuroprotection, anti-inflammatory properties, hepatorenal protection, and anticancer activity. They are often used as coloring and seasoning agents. Due to the limited content of crocins in plants and the high cost of chemical synthesis, the supply of crocins is insufficient to meet current demand. The biosynthetic pathways for crocins have been elucidated to date, which allows the heterologous production of these valuable compounds in microorganisms by fermentation. This review article provides a comprehensive overview of the chemistry, pharmacological activity, biosynthetic pathways, and heterologous production of crocins, aiming to lay the foundation for the large-scale production of these valuable natural products by using engineered microbial cell factories.

14.
J Chromatogr A ; 1720: 464814, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38490140

RESUMO

A magnetic polyimide (PI) nanocomposite has been synthesized by phase inversion of PI and simultaneous encapsulation of Fe3O4 nanoparticles. The Fe3O4/PI nanocomposite was characterized by a variety of characterization techniques, including infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption-desorption isotherms, and vibrating sample magnetometry. The results showed that the prepared nanocomposite had a homogeneous structure, adequate specific surface area (76.1 m2/g) and high saturation magnetization (42.9 emu/g). Using parabens as model analytes, the performance of the Fe3O4/PI nanocomposite as an adsorbent for magnetic solid-phase extraction (MSPE) was evaluated. The extracted parabens were desorbed and determined by gas chromatography-mass spectrometry (GC-MS). The parameters affecting the extraction and desorption efficiency of parabens were optimized. Under the optimal conditions, the developed MSPE/GC-MS method was successfully applied to the determination of parabens in cooking wine. The MSPE/GC-MS method exhibited broad linearity (0.2-100 µg/L), low detection limits (0.04-0.05 µg/L), and satisfactory extraction recoveries (79.2 %-113.3 %) with relative standard deviations (RSDs) ranging from 0.7 % to 10.4 %. For real cooking wine samples, the spiked recoveries ranged from 91.7 % to 118.7 % with RSDs of 1.0 %-11.2 %. The results demonstrated that the Fe3O4/PI nanocomposite was an effective adsorbent, and this work provides a novel reference for the easy preparation of magnetic adsorbent materials.


Assuntos
Nanocompostos , Vinho , Cromatografia Gasosa-Espectrometria de Massas , Parabenos , Adsorção , Fenômenos Magnéticos , Extração em Fase Sólida/métodos , Nanocompostos/química , Limite de Detecção , Cromatografia Líquida de Alta Pressão/métodos
15.
J Med Chem ; 67(6): 4624-4640, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38483132

RESUMO

Dynemicin A has been the sole prototypical anthraquinone-fused enediyne (AFE) explored since its discovery in 1989. This study investigates the distinct DNA binding and cleavage mechanisms of emerging AFEs, represented by tiancimycins and yangpumicins, along with semisynthetic analogues. Our findings reveal their potent cytotoxicity against various tumor cell lines, while 18-methoxy tiancimycin A treatment could significantly suppress breast tumor growth with minimal toxicity. One of the most potent AFEs, i.e., tiancimycin A, preferentially targets DNA sequences 5'-ATT, 5'-CTT, 5'-GAA, 5'-GAT, and 5'-TTA. Molecular dynamics simulations suggest that emerging AFEs intercalate deeper into AT-rich DNA base pairs compared to dynemicin A. Importantly, tiancimycin A may equilibrate between insertional and intercalative modes without deintercalation, enabling selective cleavage of T and A bases. This study underscores how subtle structural variations among AFEs significantly influence their DNA recognition and cleavage, facilitating future design of novel AFEs as potent and selective payloads for antibody-drug conjugates.


Assuntos
DNA , Enedi-Inos , Enedi-Inos/química , Antraquinonas/química , Antibióticos Antineoplásicos/química
16.
Angew Chem Int Ed Engl ; 63(19): e202401364, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38465572

RESUMO

The development of high-purity and high-energy-density green hydrogen through water electrolysis holds immense promise, but issues such as electrocatalyst costs and power consumption have hampered its practical application. In this study, we present a promising solution to these challenges through the use of a high-performance bifunctional electrocatalyst for energy-efficient hydrogen production via coupled hydrazine degradation. The biphasic metal nitrides with highly lattice-matched structures are deliberately constructed, forming an enhanced local electric field between the electron-rich Ni3N and electron-deficient Co3N. Additionally, Mn is introduced as an electric field engine to further activate electron redistribution. Our Mn@Ni3N-Co3N/NF bifunctional electrocatalyst achieves industrial-grade current densities of 500 mA cm-2 at 0.49 V without degradation, saving at least 53.3 % energy consumption compared to conventional alkaline water electrolysis. This work will stimulate the further development of metal nitride electrocatalysts and also provide new perspectives on low-cost hydrogen production and environmental protection.

17.
Angew Chem Int Ed Engl ; 63(16): e202401209, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38400604

RESUMO

Self-propelled micro/nanomotors (MNMs) have shown great application potential in biomedicine, sensing, environmental remediation, etc. In the past decade, various strategies or technologies have been used to prepare and functionalize MNMs. However, the current preparation strategies of the MNMs were mainly following the pre-designed methods based on specific tasks to introduce expected functional parts on the various micro/nanocarriers, which lacks a universal platform and common features, making it difficult to apply to different application scenarios. Here, we have developed a modular assembly strategy based on host-guest chemistry, which enables the on-demand construction of imaging-trackable nanomotors mounted with suitable driving and imaging modules using a universal assembly platform, according to different application scenarios. These assembled nanomotors exhibited enhanced diffusion behavior driven by enzymatic reactions. The loaded imaging functions were used to dynamically trace the swarm motion behavior of assembled nanomotors with corresponding fuel conditions both in vitro and in vivo. The modular assembly strategy endowed with host-guest interaction provides a universal approach to producing multifunctional MNMs in a facile and controllable manner, which paves the way for the future development of MNMs systems with programmable functions.


Assuntos
Recuperação e Remediação Ambiental , Nanoestruturas , Nanotecnologia/métodos , Nanoestruturas/química
18.
Molecules ; 29(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38398604

RESUMO

Andrographis paniculata is a medicinal plant traditionally used to produce diterpene lactones and flavonoids, which possess various biological activities. Widely distributed in China, India, and other Southeast Asia countries, A. paniculata has become an important economic crop, significantly treating SARS-CoV-2, and is being cultivated on a large scale in southern China. The biosynthesis of active ingredients in A. paniculata are regulated and controlled by genes, but their specific roles are still not fully understood. To further explore the growth regulation factors and utilization of its medicinal parts of this industrial crop, chemical and transcriptome analyses were conducted on the roots, stems, and leaves of A. paniculata to identify the biosynthesis pathways and related candidate genes of the active ingredients. The chemical analysis revealed that the main components of A. paniculata were diterpene lactones and flavonoids, which displayed potential ability to treat SARS-CoV-2 through molecular docking. Moreover, the transcriptome sequencing annotated a total of 40,850 unigenes, including 7962 differentially expressed genes. Among these, 120 genes were involved in diterpene lactone biosynthesis and 60 genes were involved in flavonoid biosynthesis. The expression of diterpene lactone-related genes was the highest in leaves and the lowest in roots, consistent with our content determination results. It is speculated that these highly expressed genes in leaves may be involved in the biosynthesis pathway of diterpenes. Furthermore, two class Ⅰ terpene synthases in A. paniculata transcriptome were also annotated, providing reference for the downstream pathway of the diterpene lactone biosynthesis. With their excellent market value, our experiments will promote the study of the biosynthetic genes for active ingredients in A. paniculata and provide insights for subsequent in vitro biosynthesis.


Assuntos
Andrographis , Diterpenos , Terpenos/metabolismo , Transcriptoma , Andrographis/genética , Andrographis/química , Flavonoides/metabolismo , Simulação de Acoplamento Molecular , Diterpenos/química , Lactonas/metabolismo , Antivirais/metabolismo
19.
Adv Sci (Weinh) ; 11(17): e2307865, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38355309

RESUMO

Although natural products are essential sources of small-molecule antitumor drugs, some can exert substantial toxicities, limiting their clinical utility. Anthraquinone-fused enediyne natural products are remarkably potent antitumor drug candidates, and uncialamycin and tiancimycin (TNM) A are under development as antibody-drug conjugates. Herein, a novel drug delivery system is introduced for TNM A using anti-human epidermal growth factor receptor 2 (HER2) immunoliposomes (ILs). Trastuzumab-coated TNM A-loaded ILs (HER2-TNM A-ILs) is engineered with an average particle size of 182.8 ± 2.1 nm and a zeta potential of 1.75 ± 0.12 mV. Compared with liposomes lacking trastuzumab, HER2-TNM A-ILs exhibited selective toxicity against HER2-positive KPL-4 and SKBR3 cells. Coumarin-6, a fluorescent TNM A surrogate, is encapsulated within anti-HER2 ILs; the resultant ILs have enhanced cellular uptake in KPL-4 and SKBR3 cells when compared with control liposomes. Furthermore, ILs loaded with more Cy5.5 accumulated in KPL-4 mouse tumors. A single HER2-TNM A-IL dose (0.02 mg kg-1) suppressed the growth of HER2-positive KPL-4 mouse tumors without apparent toxicity. This study not only provides a straightforward method for the effective delivery of TNM A against HER2-positive breast tumors but also underscores the potential of IL-based drug delivery systems when employing highly potent cytotoxins as payloads.


Assuntos
Antraquinonas , Antineoplásicos , Sistemas de Liberação de Medicamentos , Enedi-Inos , Lipossomos , Receptor ErbB-2 , Animais , Camundongos , Enedi-Inos/química , Enedi-Inos/farmacologia , Receptor ErbB-2/imunologia , Antraquinonas/farmacologia , Antraquinonas/administração & dosagem , Humanos , Sistemas de Liberação de Medicamentos/métodos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Feminino , Modelos Animais de Doenças , Trastuzumab/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia
20.
ACS Sens ; 9(3): 1331-1338, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38377515

RESUMO

Fuel cell gas sensors have emerged as promising advanced sensing devices owing to their advantageous features of low power consumption and cost-effectiveness. However, commercially available Pt/C electrodes pose significant challenges in terms of stability and accurate detection of low concentrations of target gases. Here, we introduce an efficient Cu-Pt/CrN-based fuel cell gas sensor, designed specifically for the ultrasensitive detection of hydrogen sulfide (H2S) at room temperature. Compared to the commercial Pt/C sensor, the Cu-Pt/CrN sensor exhibits excellent sensitivity (0.26 µA/ppm), with an increase in the selectivity by a factor of 2.5, and demonstrates good stability over a 2 month period. The enhanced sensing performance can be attributed to the modulation of the electronic arrangement of Pt by Cu, resulting in an augmentation of H2S adsorption. The Cu-Pt/CrN fuel cell gas sensor provides an opportunity for detecting parts per billion-level H2S in various applications.


Assuntos
Gases , Sulfeto de Hidrogênio , Temperatura , Eletrodos
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