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1.
Adv Sci (Weinh) ; : e2309473, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38978348

RESUMEN

Melatonin (N-acetyl-5-methoxytryptamine) is reported to improve mood disorders in perimenopausal women and gut microbiome composition is altered during menopausal period. The possible role of microbiome in the treatment effect of melatonin on menopausal depression remains unknown. Here, it is shown that melatonin treatment reverses the gut microbiota dysbiosis and depressive-like behaviors in ovariectomy (OVX) operated mice. This effect of melatonin is prevented by antibiotic cocktails (ABX) treatment. Transferring microbiota harvested from adolescent female mice to OVX-operated mice is sufficient to ameliorate depressive-like behaviors. Conversely, microbiota transplantation from OVX-operated mice or melatonin-treated OVX-operated mice to naïve recipient mice exhibits similar phenotypes to donors. The colonization of Alistipes Inops, which is abundant in OVX-operated mice, confers the recipient with depressive-like behaviors. Further investigation indicates that the expansion of Alistipes Inops induced by OVX leads to the degradation of intestinal tryptophan, which destroys systemic tryptophan availability. Melatonin supplementation restores systemic tryptophan metabolic disorders by suppressing the growth of Alistipes Inops, which ameliorates depressive-like behaviors. These results highlight the previously unrecognized role of Alistipes Inops in the modulation of OVX-induced behavioral disorders and suggest that the application of melatonin to inhibit Alistipes Inops may serve as a potential strategy for preventing menopausal depressive symptoms.

2.
J Pharm Anal ; 14(6): 100969, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39027913

RESUMEN

Hypoxia is the common characteristic of almost all solid tumors, which prevents therapeutic drugs from reaching the tumors. Therefore, the development of new targeted agents for the accurate diagnosis of hypoxia tumors is widely concerned. As carbonic anhydrase IX (CA IX) is abundantly distributed on the hypoxia tumor cells, it is considered as a potential tumor biomarker. 4-(2-Aminoethyl)benzenesulfonamide (ABS) as a CA IX inhibitor has inherent inhibitory activity and good targeting effect. In this study, Ag2S quantum dots (QDs) were used as the carrier to prepare a novel diagnostic and therapeutic bioprobe (Ag2S@polyethylene glycol (PEG)-ABS) through ligand exchange and amide condensation reaction. Ag2S@PEG-ABS can selectively target tumors by surface-modified ABS and achieve accurate tumor imaging by the near infrared-II (NIR-II) fluorescence characteristics of Ag2S QDs. PEG modification of Ag2S QDs greatly improves its water solubility and stability, and therefore achieves high photothermal stability and high photothermal conversion efficiency (PCE) of 45.17%. Under laser irradiation, Ag2S@PEG-ABS has powerful photothermal and inherent antitumor combinations on colon cancer cells (CT-26) in vitro. It also has been proved that Ag2S@PEG-ABS can realize the effective treatment of hypoxia tumors in vivo and show good biocompatibility. Therefore, it is a new efficient integrated platform for the diagnosis and treatment of hypoxia tumors.

3.
Analyst ; 149(13): 3673-3680, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38819227

RESUMEN

Benzoylurea (BU) insecticides have been widely used for pest control as third-generation insecticides. Considering that their residues in food may cause adverse effects on human health, the upper limits of BUs remaining in food have been set by the administration. Therefore, it is essential to develop a sensitive and efficient analytical method to determine the residues of BUs in food. Stir bar sorptive extraction (SBSE) is a novel sample preparation technique, and stainless steel wire (SSW) is an ideal substrate for an SBSE device. In this work, a novel SBSE device of SSW jacket-free stir bar with a dumbbell shape was designed and prepared. The conjugated microporous polymer CMP-F6, which possesses a porous structure, high hydrophobicity and rich fluorine-containing functional groups, was immobilized on the surface of SSW by the method of polyacrylonitrile glue adhesion. Compared with previous studies, which used SSW as a substrate, the method of etching partial SSW with hydrochloric acid, on the one hand, made the surface of SSW rough and easy to modify the extraction coating, and on the other hand, converted itself into a dumbbell-shaped structure, which is conducive to improving the extraction efficiency and stability of the SBSE device. The method of SBSE-HPLC-UV was established for determining five BUs. Owing to the hydrophobic interaction and F-F interaction between CMP-F6 and analytes, this method showed good extraction efficiency and had good linearity (R2 ≥ 0.9945) and high sensitivity (LODs in the range of 0.1-0.2 ng mL-1). It was used for the analysis of benzoylurea in an apple juice sample, and the recoveries were 74.3-117.9%.


Asunto(s)
Jugos de Frutas y Vegetales , Polímeros , Acero Inoxidable , Acero Inoxidable/química , Porosidad , Jugos de Frutas y Vegetales/análisis , Polímeros/química , Límite de Detección , Contaminación de Alimentos/análisis , Urea/química , Urea/análisis , Insecticidas/análisis , Insecticidas/aislamiento & purificación , Insecticidas/química , Extracción en Fase Sólida/métodos , Cromatografía Líquida de Alta Presión/métodos , Adsorción , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/aislamiento & purificación
4.
Pestic Biochem Physiol ; 201: 105874, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38685243

RESUMEN

In insects, chemosensory proteins (CSPs) play an important role in the perception of the external environment and have been widely used for protein-binding characterization. Riptortus pedestris has received increased attention as a potential cause of soybean staygreen syndrome in recent years. In this study, we found that RpedCSP4 expression in the antennae of adult R. pedestris increased with age, with no significant difference in expression level observed between males and females, as determined through quantitative real-time polymerase chain reaction (qRT-PCR). Subsequently, we investigated the ability of RpedCSP4 to bind various ligands (five aggregated pheromone components and 13 soybean volatiles) using a prokaryotic expression system and fluorescence competitive binding assays. We found that RpedCSP4 binds to three aggregated pheromone components of R. pedestris, namely, ((E)-2-hexenyl (Z)-3-hexenoate (E2Z3), (E)-2-hexenyl (E)-2-hexenoate (E2E2), and (E)-2-hexenyl hexenoate (E2HH)), and that its binding capacities are most stable under acidic condition. Finally, the structure and protein-ligand interactions of RpedCSP4 were further analyzed via homology modeling, molecular docking, and targeted mutagenesis experiments. The L29A mutant exhibited a loss of binding ability to these three aggregated pheromone components. Our results show that the olfactory function of RpedCSP4 provides new insights into the binding mechanism of RpedCSPs to aggregation pheromones and contributes to discover new target candidates that will provide a theoretical basis for future population control of R. pedestris.


Asunto(s)
Proteínas de Insectos , Feromonas , Animales , Feromonas/metabolismo , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/química , Masculino , Femenino , Unión Proteica , Heterópteros/metabolismo , Heterópteros/genética
5.
Brain Behav ; 14(3): e3457, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38450910

RESUMEN

INTRODUCTION: Repeated exposure to cocaine induces microglial activation. Cocaine exposure also induces a release of high mobility group box-1 (HMGB1) from neurons into the extracellular space in the nucleus accumbens (NAc). HMGB1 is an important late inflammatory mediator of microglial activation. However, whether the secretion of HMGB1 acts on microglia or contributes to cocaine addiction is largely unknown. METHODS: Rats were trained by intraperitoneal cocaine administration and cocaine-induced conditioned place preference (CPP). Expression of HMGB1 was regulated by viral vectors. Activation of microglia was inhibited by minocycline. Interaction of HMGB1 and the receptor for advanced glycation end products (RAGE) was disrupted by peptide. RESULTS: Cocaine injection facilitated HMGB1 signaling, together with the delayed activation of microglia concurrently in the NAc. Furthermore, the inhibition of HMGB1 or microglia activation attenuated cocaine-induced CPP. Box A, a specific antagonist to interrupt the interaction of HMGB1 and RAGE, abolished the expression of cocaine reward memory. Meanwhile, the inhibition of HMGB1-RAGE interaction suppressed cocaine-induced microglial activation, as well as the consolidation of cocaine-induced memory. CONCLUSION: All above results suggest that the neural HMGB1 induces activation of microglia through RAGE, which contributes to the consolidation of cocaine reward memory. These findings offer HMGB1-RAGE axis as a new target for the treatment of drug addiction.


Asunto(s)
Cocaína , Proteína HMGB1 , Animales , Ratas , Núcleo Accumbens , Microglía , Receptor para Productos Finales de Glicación Avanzada , Cocaína/farmacología
6.
PLoS One ; 18(10): e0251224, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37819923

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0095259.].

7.
Waste Manag ; 171: 365-374, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37757615

RESUMEN

Incineration of organic solid wastes is accompanied by the heavy metal emission through flue gas. As an inexpensive and efficient heavy metal adsorbent, the improvement of kaolinite adsorption performance for heavy metals has drawn widespread interests. In this work, the interaction mechanisms between various kaolinite surfaces and Cd/Pb species are explored through first principles calculations. The results show that the combination of Fe doping and dehydroxylation enhances the activity of kaolinite surfaces, analysis of adsorption configurations reveal that both Cd and Pb species are immobilized through chemisorption on the -H + Fe surface. At the microscopic level, further electronic structure analysis shows that the composite modified kaolinite surface has more electron transfer and more pronounced orbital hybridization and overlap compared to the original kaolinite surface, demonstrating that the modification means of dehydroxylation and Fe doping indeed enhanced the activity of the kaolinite surface, especially the activity of the O atoms in the vicinity of the Fe atom and that the O atoms are more efficiently bonded as ionic connecting Cd/Pb species for the purpose of trapping Cd/Pb species. This study points out the research direction and provides basic theoretical support for the development of new kaolinite adsorbents in the future.

8.
Pestic Biochem Physiol ; 194: 105513, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37532328

RESUMEN

Riptortus pedestris (bean bug), a common soybean pest, has a highly developed olfactory system to find hosts for feeding and oviposition. Chemosensory proteins (CSPs) have been identified in many insect species; however, their functions in R. pedestris remain unknown. In this study, quantitative real time-polymerase chain reaction (qRT-PCR) revealed that the expression of RpedCSP12 in the adult antennae of R. pedestris increased with age. Moreover, a significant difference in the expression levels of RpedCSP12 was observed between male and female antennae at one and three days of age. We also investigated the binding ability of RpedCSP12 to different ligands using a prokaryotic expression system and fluorescence competitive binding assays. We found that RpedCSP12 only bound to one aggregation pheromone, (E)-2-hexenyl (Z)-3-hexenoate, and its binding decreased with increasing pH. Furthermore, homology modelling, molecular docking, and site-directed mutagenesis revealed that the Y27A, L74A, and L85A mutants lost their binding ability to (E)-2-hexenyl (Z)-3-hexenoate. Our findings highlight the olfactory roles of RpedCSP12, providing insights into the mechanism by which RpedCSPs bind to aggregation pheromones. Therefore, our study can be used as a theoretical basis for the population control of R. pedestris in the future.


Asunto(s)
Heterópteros , Feromonas , Animales , Femenino , Simulación del Acoplamiento Molecular , Heterópteros/genética , Glycine max
9.
Cell Discov ; 9(1): 90, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37644025

RESUMEN

Dysfunctional autophagy and impairment of adult hippocampal neurogenesis (AHN) each contribute to the pathogenesis of major depressive disorder (MDD). However, whether dysfunctional autophagy is linked to aberrant AHN underlying MDD remains unclear. Here we demonstrate that the expression of nuclear receptor binding factor 2 (NRBF2), a component of autophagy-associated PIK3C3/VPS34-containing phosphatidylinositol 3-kinase complex, is attenuated in the dentate gyrus (DG) under chronic stress. NRBF2 deficiency inhibits the activity of the VPS34 complex and impairs autophagic flux in adult neural stem cells (aNSCs). Moreover, loss of NRBF2 disrupts the neurogenesis-related protein network and causes exhaustion of aNSC pool, leading to the depression-like phenotype. Strikingly, overexpressing NRBF2 in aNSCs of the DG is sufficient to rescue impaired AHN and depression-like phenotype of mice. Our findings reveal a significant role of NRBF2-dependent autophagy in preventing chronic stress-induced AHN impairment and suggest the therapeutic potential of targeting NRBF2 in MDD treatment.

10.
ACS Appl Mater Interfaces ; 15(28): 33890-33902, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37418240

RESUMEN

Colorectal cancer (CRC) is presently the third deadliest cancer in the world. This malignant cancer usually precedes the progression of precancerous lesions, and it is challenging to distinguish its nuanced morphological changes. Molecular-based near-infrared-II (NIR-II) fluorescence imaging can effectively recognize lesion targets to improve image contrast and increase early tumor detection compared with traditional wide-light screening endoscopy. c-Met has been determined to be overexpressed in advanced stages of CRC and is considered to be a potent tumor biomarker. Herein, based on the well-targeted inhibitory effect of Crizotinib on c-Met positive tumor cells, the dye IR808 was covalently combined with the drug molecule Crizotinib, resulting in the synthesis of a NIR fluorescent probe Crizotinib-IR808 targeting c-Met positive tumor cells. Then, water-insoluble Crizotinib-IR808 was fabricated by using bovine serum albumin (BSA) nanoparticles (NPs) with excellent biocompatibility and biosafety. The prepared Crizotinib-IR808@BSA NPs showed tumor targeting capability as well as use for noninvasive biomedical vascular NIR-II imaging with intraoperative real-time NIR-II imaging to guide tumor resection. Under 808 nm laser irradiation, Crizotinib-IR808@BSA NPs exhibited synergistic chemophototherapy effects on tumors. In conclusion, this innovative imaging-mediated multifunctional combination therapy strategy with good c-Met targeting ability may provide a new approach for colorectal cancer treatment.


Asunto(s)
Neoplasias Colorrectales , Nanopartículas , Humanos , Crizotinib/farmacología , Colorantes Fluorescentes/farmacología , Albúmina Sérica Bovina , Imagen Óptica/métodos , Neoplasias Colorrectales/patología , Línea Celular Tumoral
11.
J Neuroinflammation ; 20(1): 157, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37391731

RESUMEN

BACKGROUND: Neuroinflammation and microglia play critical roles in the development of depression. Cluster of differentiation 200 (CD200) is an anti-inflammatory glycoprotein that is mainly expressed in neurons, and its receptor CD200R1 is primarily in microglia. Although the CD200-CD200R1 pathway is necessary for microglial activation, its role in the pathophysiology of depression remains unknown. METHODS: The chronic social defeat stress (CSDS) with behavioral tests were performed to investigate the effect of CD200 on the depressive-like behaviors. Viral vectors were used to overexpress or knockdown of CD200. The levels of CD200 and inflammatory cytokines were tested with molecular biological techniques. The status of microglia, the expression of BDNF and neurogenesis were detected with immunofluorescence imaging. RESULTS: We found that the expression of CD200 was decreased in the dentate gyrus (DG) region of mice experienced CSDS. Overexpression of CD200 alleviated the depressive-like behaviors of stressed mice and inhibition of CD200 facilitated the susceptibility to stress. When CD200R1 receptors on microglia were knocked down, CD200 was unable to exert its role in alleviating depressive-like behavior. Microglia in the DG brain region were morphologically activated after exposure to CSDS. In contrast, exogenous administration of CD200 inhibited microglia hyperactivation, alleviated neuroinflammatory response in hippocampus, and increased the expression of BDNF, which in turn ameliorated adult hippocampal neurogenesis impairment in the DG induced by CSDS. CONCLUSIONS: Taken together, these results suggest that CD200-mediated alleviation of microglia hyperactivation contributes to the antidepressant effect of neurogenesis in dentate gyrus in mice.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Microglía , Animales , Ratones , Hipocampo , Neurogénesis , Giro Dentado
12.
Small ; 19(41): e2303296, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37294167

RESUMEN

Hard Carbon have become the most promising anode candidates for sodium-ion batteries, but the poor rate performance and cycle life remain key issues. In this work, N-doped hard carbon with abundant defects and expanded interlayer spacing is constructed by using carboxymethyl cellulose sodium as precursor with the assistance of graphitic carbon nitride. The formation of N-doped nanosheet structure is realized by the CN• or CC• radicals generated through the conversion of nitrile intermediates in the pyrolysis process. This greatly enhances the rate capability (192.8 mAh g-1 at 5.0 A g-1 ) and ultra-long cycle stability (233.3 mAh g-1 after 2000 cycles at 0.5 A g-1 ). In situ Raman spectroscopy, ex situ X-ray diffraction and X-ray photoelectron spectroscopy analysis in combination with comprehensive electrochemical characterizations, reveal that the interlayer insertion coordinated quasi-metallic sodium storage in the low potential plateau region and adsorption storage in the high potential sloping region. The first-principles density functional theory calculations further demonstrate strong coordination effect on nitrogen defect sites to capture sodium, especially with pyrrolic N, uncovering the formation mechanism of quasi-metallic bond in the sodium storage. This work provides new insights into the sodium storage mechanism of high-performance carbonaceous materials, and offers new opportunities for better design of hard carbon anode.

13.
Sci Adv ; 9(20): eadf8698, 2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-37205756

RESUMEN

Cyclin-dependent kinase 12 (CDK12) interacts with cyclin K to form a functional nuclear kinase that promotes processive transcription elongation through phosphorylation of the C-terminal domain of RNA polymerase II (Pol II). To gain a comprehensive understanding of CDK12's cellular function, we used chemical genetic and phosphoproteomic screening to identify a landscape of nuclear human CDK12 substrates, including regulators of transcription, chromatin organization, and RNA splicing. We further validated LEO1, a subunit of the polymerase-associated factor 1 complex (PAF1C), as a bona fide cellular substrate of CDK12. Acute depletion of LEO1, or substituting LEO1 phosphorylation sites with alanine, attenuated PAF1C association with elongating Pol II and impaired processive transcription elongation. Moreover, we discovered that LEO1 interacts with and is dephosphorylated by the Integrator-PP2A complex (INTAC) and that INTAC depletion promotes the association of PAF1C with Pol II. Together, this study reveals an uncharacterized role for CDK12 and INTAC in regulating LEO1 phosphorylation, providing important insights into gene transcription and its regulation.


Asunto(s)
Quinasas Ciclina-Dependientes , ARN Polimerasa II , Humanos , Fosforilación/genética , Quinasas Ciclina-Dependientes/genética , Quinasas Ciclina-Dependientes/metabolismo , ARN Polimerasa II/metabolismo , Núcleo Celular/metabolismo , Transcripción Genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
14.
Colloids Surf B Biointerfaces ; 226: 113310, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37054465

RESUMEN

The size of the nanoparticles is moderate and the dispersion is well, which will not be recognized nonspecifically and clearance by the endothelial reticular system. In this study, stimuli-responsive polypeptides nano-delivery system has been constructed, which can realize the response to various stimuli in the tumor microenvironment. Tertiary amine groups are grafted to the side chain of polypeptides as the point of charge reversal and particle expansion. In addition, a new kind of liquid crystal monomer was prepared by substituting cholesterol-cysteamine, which can promote polymers to realize the transformation of spatial conformation by adjusting the ordered arrangement of macromolecules. The introduction of hydrophobic elements greatly enhanced the self-assembly performance of polypeptides, which could effectively improve the drug loading and encapsulation rate of nanoparticles. Nanoparticles could achieve targeted aggregation in tumor tissues, and there were no toxicity and side effects on normal bodies during treatment, with good safety in vivo.


Asunto(s)
Doxorrubicina , Nanopartículas , Doxorrubicina/química , Sistemas de Liberación de Medicamentos , Nanopartículas/uso terapéutico , Nanopartículas/química , Polímeros/química , Péptidos/química , Concentración de Iones de Hidrógeno , Portadores de Fármacos/química , Liberación de Fármacos , Línea Celular Tumoral
15.
Colloids Surf B Biointerfaces ; 224: 113232, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36868182

RESUMEN

A series of novel poly(amino acid)s materials were designed to prepare drug-loaded nanoparticles by physical encapsulation and chemical bonding. The side chain of the polymer contains a large number of amino groups, which effectively increases the loading rate of doxorubicin (DOX). The structure contains disulfide bonds that showing a strong response to the redox environment, which can achieve targeted drug release in the tumor microenvironment. Nanoparticles mainly present spherical morphology with the suitable size for participating in systemic circulation. cell experiments demonstrate the non-toxicity and good cellular uptake behavior of polymers. In vivo anti-tumor experiments shows nanoparticles could inhibit tumor growth and effectively reduce the side effects of DOX.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Sistemas de Liberación de Medicamentos , Preparaciones de Acción Retardada/farmacología , Aminoácidos , Sistema de Administración de Fármacos con Nanopartículas , Doxorrubicina/farmacología , Doxorrubicina/química , Polímeros/química , Portadores de Fármacos/química , Nanopartículas/química , Oxidación-Reducción , Concentración de Iones de Hidrógeno , Microambiente Tumoral
16.
Mol Psychiatry ; 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36914810

RESUMEN

Recent studies based on animal models of various neurological disorders have indicated that mitophagy, a selective autophagy that eliminates damaged and superfluous mitochondria through autophagic degradation, may be involved in various neurological diseases. As an important mechanism of cellular stress response, much less is known about the role of mitophagy in stress-related mood disorders. Here, we found that tumor necrosis factor-α (TNF-α), an inflammation cytokine that plays a particular role in stress responses, impaired the mitophagy in the medial prefrontal cortex (mPFC) via triggering degradation of an outer mitochondrial membrane protein, NIP3-like protein X (NIX). The deficits in the NIX-mediated mitophagy by TNF-α led to the accumulation of damaged mitochondria, which triggered synaptic defects and behavioral abnormalities. Genetic ablation of NIX in the excitatory neurons of mPFC caused passive coping behaviors to stress, and overexpression of NIX in the mPFC improved TNF-α-induced synaptic and behavioral abnormalities. Notably, ketamine, a rapid on-set and long-lasting antidepressant, reversed the TNF-α-induced behavioral abnormalities through activation of NIX-mediated mitophagy. Furthermore, the downregulation of NIX level was also observed in the blood of major depressive disorder patients and the mPFC tissue of animal models. Infliximab, a clinically used TNF-α antagonist, alleviated both chronic stress- and inflammation-induced behavioral abnormalities via restoring NIX level. Taken together, these results suggest that NIX-mediated mitophagy links inflammation signaling to passive coping behaviors to stress, which underlies the pathophysiology of stress-related emotional disorders.

17.
Drug Deliv Transl Res ; 13(9): 2394-2406, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36913103

RESUMEN

Enhancing tissue permeability and achieving drug aggregation is the key to targeted tumor therapy. A series triblock copolymers of poly(ethylene glycol)-poly(L-lysine)-poly(L-glutamine) were synthesized by ring-opening polymerization, and charge-convertible nano-delivery system was constructed by loading doxorubicin (DOX) with 2-(hexaethylimide) ethanol on side chain. In normal environment (pH = 7.4), the zeta potential of the drug-loaded nanoparticle solution is negative, which is conducive to avoiding the identification and clearance of nanoparticles by the reticulo-endothelial system, while potential-reversal can be achieved in the tumor microenvironment, which effectively promotes cellular uptake. Nanoparticles could effectively reduce the distribution of DOX in normal tissues and achieve targeted aggregation at tumor sites, which can effectively improve the antitumor effect, while would not causing toxicity and damage to normal body.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Aminoácidos , Sistemas de Liberación de Medicamentos , Preparaciones de Acción Retardada , Doxorrubicina/química , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Concentración de Iones de Hidrógeno , Portadores de Fármacos/química , Microambiente Tumoral
18.
Sci Total Environ ; 857(Pt 3): 159712, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36302402

RESUMEN

Facing the increasing demand of atmosphere pollutant control, selective catalytic reduction (SCR) technology has been widely applied in various industries for NOx abatement. However, in the condition of complicated flue gas components, the heavy metal issue is a great challenge to the catalyst deactivation and atmospheric pollution control. In this review, with the comprehensive consideration of SCR catalysts in heavy metal-rich flue gas scenarios, the distribution character of heavy metals in SCR system is firstly summarized, then the detailed interaction mechanism between heavy metals and the vanadium­titanium-based catalyst is discussed. Focusing on the mercury oxidation as well as against arsenic/lead poisoning, certain modification strategies are also concluded to develop novel SCR catalysts with multiple functions. Furthermore, the state-of-the-art technologies regarding the regeneration, the valuable metal recovery, and the harmless treatment of the spent SCR catalyst are also reported. This paper provides theoretical guidance for the manufacture of novel SCR catalysts under multiple scenarios, as well as the synergistic control of NOx and heavy metals.


Asunto(s)
Mercurio , Titanio , Vanadio , Catálisis , Oxidación-Reducción
19.
Small Methods ; 7(2): e2201390, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36541738

RESUMEN

The poor electrode kinetics and low conductivity of the LiMn0.8 Fe0.2 PO4 cathode seriously impede its practical application. Here, an effective strategy of boron-catalyzed graphitization carbon coating layer is proposed to stabilize the nanostructure and improve the kinetic properties and Li-storage capability of LiMn0.8 Fe0.2 PO4 nanocrystals for rechargeable lithium-ion batteries. The graphite-like BC3 is derived from B-catalyzed graphitization coating layers, which can not only effectively maintain the dynamic stability of the LiMn0.8 Fe0.2 PO4 nanostructure during cycling, but also plays an important role in enhancing the conductivity and Li+ migration kinetics of LiMn0.8 Fe0.2 PO4 @B-C. The optimized LiMn0.8 Fe0.2 PO4 @B-C exhibits the fastest intercalation/deintercalation kinetics, highest electrical conductivity (8.41 × 10-2 S cm-1 ), Li+ diffusion coefficient (6.17 × 10-12 cm2 s-1 ), and Li-storage performance among three comparison samples (B-C0, B-C6, and B-C9). The highly reversible properties and structural stability of LiMn0.8 Fe0.2 PO4 @B-C are further proved by operando XRD analysis. The B-catalyzed graphitization carbon coating strategy is expected to be an effective pathway to overcome the inherent drawbacks of the high-energy density LiMn0.8 Fe0.2 PO4 cathode and to improve other cathode materials with low-conductivity and poor electrode kinetics for rechargeable second batteries.

20.
Brain Behav Immun ; 109: 23-36, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36581303

RESUMEN

Synapse loss in medial prefrontal cortex (mPFC) has been implicated in stress-related mood disorders, such as depression. However, the exact effect of synapse elimination in the depression and how it is triggered are largely unknown. Through repeated longitudinal imaging of mPFC in the living brain, we found both presynaptic and postsynaptic components were declined, together with the impairment of synapse remodeling and cross-synaptic signal transmission in the mPFC during chronic stress. Meanwhile, chronic stress also induced excessive microglia phagocytosis, leading to engulfment of excitatory synapses. Further investigation revealed that the elevated complement C3 during the stress acted as the tag of synapses to be eliminated by microglia. Besides, chronic stress induced a reduction of the connectivity between the mPFC and neighbor regions. C3 knockout mice displayed significant reduction of synaptic pruning and alleviation of disrupted functional connectivity in mPFC, resulting in more resilience to chronic stress. These results indicate that complement-mediated excessive microglia phagocytosis in adulthood induces synaptic dysfunction and cortical hypo-connectivity, leading to stress-related behavioral abnormality.


Asunto(s)
Microglía , Derrota Social , Ratones , Animales , Sinapsis , Ratones Noqueados , Plasticidad Neuronal
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