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1.
Nature ; 628(8006): 93-98, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38382650

RESUMEN

Defects at the top and bottom interfaces of three-dimensional (3D) perovskite photoabsorbers diminish the performance and operational stability of perovskite solar cells owing to charge recombination, ion migration and electric-field inhomogeneities1-5. Here we demonstrate that long alkyl amine ligands can generate near-phase-pure 2D perovskites at the top and bottom 3D perovskite interfaces and effectively resolve these issues. At the rear-contact side, we find that the alkyl amine ligand strengthens the interactions with the substrate through acid-base reactions with the phosphonic acid group from the organic hole-transporting self-assembled monolayer molecule, thus regulating the 2D perovskite formation. With this, inverted perovskite solar cells with double-side 2D/3D heterojunctions achieved a power conversion efficiency of 25.6% (certified 25.0%), retaining 95% of their initial power conversion efficiency after 1,000 h of 1-sun illumination at 85 °C in air.

2.
Nature ; 623(7988): 732-738, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37769785

RESUMEN

Monolithic perovskite/silicon tandem solar cells are of great appeal as they promise high power conversion efficiencies (PCEs) at affordable cost. In state-of-the-art tandems, the perovskite top cell is electrically coupled to a silicon heterojunction bottom cell by means of a self-assembled monolayer (SAM), anchored on a transparent conductive oxide (TCO), which enables efficient charge transfer between the subcells1-3. Yet reproducible, high-performance tandem solar cells require energetically homogeneous SAM coverage, which remains challenging, especially on textured silicon bottom cells. Here, we resolve this issue by using ultrathin (5-nm) amorphous indium zinc oxide (IZO) as the interconnecting TCO, exploiting its high surface-potential homogeneity resulting from the absence of crystal grains and higher density of SAM anchoring sites when compared with commonly used crystalline TCOs. Combined with optical enhancements through equally thin IZO rear electrodes and improved front contact stacks, an independently certified PCE of 32.5% was obtained, which ranks among the highest for perovskite/silicon tandems. Our ultrathin transparent contact approach reduces indium consumption by approximately 80%, which is of importance to sustainable photovoltaics manufacturing4.

3.
Lab Invest ; 104(3): 100326, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38237739

RESUMEN

To better understand the pathogenesis of acute type A aortic dissection, high-sensitivity liquid chromatography-tandem mass spectrometry/mass spectrometry (LC-MS/MS)-based proteomics and phosphoproteomics approaches were used to identify differential proteins. Heat shock protein family B (small) member 6 (HSPB6) in aortic dissection was significantly reduced in human and mouse aortic dissection samples by real-time PCR, western blotting, and immunohistochemical staining techniques. Using an HSPB6-knockout mouse, we investigated the potential role of HSPB6 in ß-aminopropionitrile monofumarate-induced aortic dissection. We found increased mortality and increased probability of ascending aortic dissection after HSPB6 knockout compared with wild-type mice. Mechanistically, our data suggest that HSPB6 deletion promoted vascular smooth muscle cell apoptosis. More importantly, HSPB6 deletion attenuated cofilin activity, leading to excessive smooth muscle cell stiffness and eventually resulting in the development of aortic dissection and rupture. Our data suggest that excessive stiffness of vascular smooth muscle cells caused by HSPB6 deficiency is a new pathogenetic mechanism leading to aortic dissection.


Asunto(s)
Disección Aórtica , Espectrometría de Masas en Tándem , Ratones , Humanos , Animales , Cromatografía Liquida , Disección Aórtica/genética , Miocitos del Músculo Liso/metabolismo , Ratones Noqueados , Modelos Animales de Enfermedad , Proteínas del Choque Térmico HSP20/metabolismo
4.
Microb Pathog ; 192: 106713, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38810765

RESUMEN

Newcastle disease virus (NDV) is the pathogen of a zoonosis that is primarily transmitted by poultry and has severe infectivity and a high fatality rate. Many studies have focused on the role of the NDV fusion (F) protein in the cell-cell membrane fusion process. However, little attention has been given to the heptad repeat region, HR4, which is located in the NDV F2 subunit. Here, site-directed mutants were constructed to study the function of the NDV F protein HR4 region and identify the key amino acids in this region. Nine conserved amino acids were substituted with alanine or the corresponding amino acid of other aligned paramyxoviruses. The desired mutants were examined for changes in fusogenic activity through three kinds of membrane fusion assays and expression and proteolysis through IFA, FACS and WB. The results showed that when conserved amino acids (L81, Y84, L88, L91, L92, P94, L95 and I99) were replaced with alanine, the fusogenic activity of the F protein was abolished, possibly because of failed protein expression not only on the cell surface but also inside cells. These data indicated that the conserved amino acids above in NDV F HR4 are critical for normal protein synthesis and expression, possibly for the stability of the F protein monomer, formation of trimer and conformational changes.


Asunto(s)
Mutagénesis Sitio-Dirigida , Virus de la Enfermedad de Newcastle , Proteínas Virales de Fusión , Internalización del Virus , Virus de la Enfermedad de Newcastle/genética , Virus de la Enfermedad de Newcastle/metabolismo , Proteínas Virales de Fusión/genética , Proteínas Virales de Fusión/metabolismo , Animales , Sustitución de Aminoácidos , Línea Celular , Mutación , Proteolisis , Fusión de Membrana
5.
Angew Chem Int Ed Engl ; 63(17): e202319400, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38284300

RESUMEN

Peptidoglycan, an essential component within the cell walls of virtually all bacteria, is composed of glycan strands linked by stem peptides that contain D-amino acids. The peptidoglycan biosynthesis machinery exhibits high tolerance to various D-amino acid derivatives. D-amino acid derivatives with different functionalities can thus be specifically incorporated into and label the peptidoglycan of bacteria, but not the host mammalian cells. This metabolic labeling strategy is highly selective, highly biocompatible, and broadly applicable, which has been utilized in various fields. This review introduces the metabolic labeling strategies of peptidoglycan by using D-amino acid derivatives, including one-step and two-step strategies. In addition, we emphasize the various applications of D-amino acid derivative-based metabolic labeling, including bacterial peptidoglycan visualization (existence, biosynthesis, and dynamics, etc.), bacterial visualization (including bacterial imaging and visualization of growth and division, metabolic activity, antibiotic susceptibility, etc.), pathogenic bacteria-targeted diagnostics and treatment (positron emission tomography (PET) imaging, photodynamic therapy, photothermal therapy, gas therapy, immunotherapy, etc.), and live bacteria-based therapy. Finally, a summary of this metabolic labeling and an outlook is provided.


Asunto(s)
Bacterias , Peptidoglicano , Peptidoglicano/metabolismo , Bacterias/metabolismo , Aminoácidos/química , Pared Celular/metabolismo
6.
Environ Res ; 216(Pt 1): 114139, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36084678

RESUMEN

Hexachlorobutadiene (HCBD) was listed as a new persistent organic pollutant for global regulation under Stockholm Convention in 2015, and there has been scarce information on its atmospheric concentrations, distributions, and emission sources. HCBD air samples were collected and analyzed to characterize concentrations and distributions at high elevation and urban sites as well as emission source locations in Northern China. We found ambient concentrations of HCBD in Northern China averaged at 34 ± 16 and 36 ± 28 pptv at urban sites in Jinan and Tai'an, respectively, and 31 ± 21 pptv at a high-elevation site Mount Tai. HCBD concentrations at the high elevation and urban sites were found to be affected by long-range transport under the influence of the East Asian monsoon climate. Over potential sources areas, we found concentrations of 76 ± 33 pptv in a mixed factory park, 59 ± 21 pptv in a rubber plant and 74 ± 8 pptv in a municipal solid waste (MSW) landfill area, which were all several times higher than in urban sites. The large concentration gradient across the various environments revealed strong emission sources of HCBD, especially over MSW landfill and Cl-compound production and application areas. An emission rate of 9.2 × 104 kg/yr and an oxidation rate of 32.9 kg/yr for HCBD were estimated for the mixed factory park. OH and Cl are much more active in reaction with HCBD than other oxidants in the atmosphere. Dry deposition and oxidation removed about 5.3% and 0.04%, respectively, of the emitted, suggesting that ∼95% of the emitted HCBD remaining in the atmosphere and could be transported for redistribution. Our findings revealed significant emission sources of HCBD in northern China, which was in turn affected by major sources in East-central China. The regional influence of HCBD pollution warrants serious concerns and points to the need to develop mitigation strategies.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Orgánicos Persistentes , Monitoreo del Ambiente , Butadienos , Atmósfera , Residuos Sólidos , China , Contaminantes Atmosféricos/análisis
7.
Clin J Sport Med ; 32(6): e647-e651, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36315830

RESUMEN

ABSTRACT: Ischiofemoral impingement is a distinct pathologic finding with abnormal osseous contact between the ischium and the lesser trochanter of the femur. Lesser trochanter excision has been recommended for recalcitrant ischiofemoral impingement through an open or endoscopic approach; however, no study has included ischial tuberosity osteophyte resection and refixation of the hamstring tendon. We report an endoscopic procedure involving ischial tuberosity osteophyte resection with refixation of the partially detached hamstring insertion through a posterior approach in the prone position. Using this technique, it is easier to reach the lesion and less likely to injure the sciatic nerve. The postoperative pain score (visual analogy score) was significantly decreased, the modified Harris hip score increased from 39 preoperatively to 86 postoperatively, and there was no adverse effect on the hamstring tendon.


Asunto(s)
Pinzamiento Femoroacetabular , Músculos Isquiosurales , Osteofito , Humanos , Isquion/cirugía , Osteofito/diagnóstico por imagen , Osteofito/cirugía , Fémur/cirugía , Fémur/patología , Endoscopía , Pinzamiento Femoroacetabular/diagnóstico por imagen , Pinzamiento Femoroacetabular/cirugía , Pinzamiento Femoroacetabular/patología , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/cirugía
8.
J Am Chem Soc ; 142(11): 5177-5183, 2020 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-32100536

RESUMEN

The insufficient intracellular H2O2 level in tumor cells is closely associated with the limited efficacy of chemodynamic therapy (CDT). Despite tremendous efforts, engineering CDT agents with a straightforward and secure H2O2 supplying ability remains a great challenge. Inspired by the balance of H2O2 generation and elimination in cancer cells, herein, a nanozyme-based H2O2 homeostasis disruptor is fabricated to elevate the intracellular H2O2 level through facilitating H2O2 production and restraining H2O2 elimination for enhanced CDT. In the formulation, the disruptor with superoxide dismutase-mimicking activity can convert O2•- to H2O2, promoting the production of H2O2. Simultaneously, the suppression of catalase activity and depletion of glutathione by the disruptor weaken the transformation of H2O2 to H2O. Thus, the well-defined system could perturb the H2O2 balance and give rise to the accumulation of H2O2 in cancer cells. The raised H2O2 level would ultimately amplify the Fenton-like reaction-based CDT efficiency. Our work not only paves a way to engineer alternative CDT agents with a H2O2 supplying ability for intensive CDT but also provides new insights into the construction of bioinspired materials.


Asunto(s)
Antineoplásicos/uso terapéutico , Peróxido de Hidrógeno/metabolismo , Estructuras Metalorgánicas/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Amitrol (Herbicida)/química , Amitrol (Herbicida)/uso terapéutico , Amitrol (Herbicida)/toxicidad , Animales , Antineoplásicos/química , Antineoplásicos/toxicidad , Catalasa/antagonistas & inhibidores , Catálisis , Línea Celular Tumoral , Quimioterapia , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/uso terapéutico , Inhibidores Enzimáticos/toxicidad , Femenino , Humanos , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/toxicidad , Ratones , Nanopartículas/química , Nanopartículas/toxicidad , Oxidación-Reducción , Polietilenglicoles/química , Polietilenglicoles/uso terapéutico , Polietilenglicoles/toxicidad
9.
Angew Chem Int Ed Engl ; 59(13): 5108-5115, 2020 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-31960567

RESUMEN

Sepsis, characterized by immoderate production of multiple reactive oxygen and nitrogen species (RONS), causes high morbidity and mortality. Despite progress made with nanozymes, efficient antioxidant therapy to eliminate these RONS remains challenging, owing largely to the specificity and low activity of exploited nanozymes. Herein, an enzyme-mimicking single-atom catalyst, Co/PMCS, features atomically dispersed coordinatively unsaturated active Co-porphyrin centers, which can rapidly obliterate multiple RONS to alleviate sepsis. Co/PMCS can eliminate O2.- and H2 O2 by mimicking superoxide dismutase, catalase, and glutathione peroxidase, while removing . OH via the oxidative-reduction cycle, with markedly higher activity than nanozymes. It can also scavenge . NO through formation of a nitrosyl-metal complex. Eventually, it can reduce proinflammatory cytokine levels, protect organs from damage, and confer a distinct survival advantage to the infected sepsis mice.


Asunto(s)
Materiales Biomiméticos/química , Catalasa/química , Glutatión Peroxidasa/química , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sepsis/metabolismo , Superóxido Dismutasa/química , Animales , Antioxidantes/química , Antioxidantes/metabolismo , Materiales Biomiméticos/metabolismo , Catalasa/metabolismo , Catálisis , Cobalto/química , Complejos de Coordinación/química , Complejos de Coordinación/metabolismo , Citocinas/metabolismo , Glutatión Peroxidasa/metabolismo , Humanos , Hierro/química , Ratones , Modelos Animales , Oxidación-Reducción , Porfirinas/química , Superóxido Dismutasa/metabolismo
10.
Chem Soc Rev ; 47(11): 4017-4072, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29611579

RESUMEN

DNA metallization has witnessed tremendous growth and development, from the initial simple synthesis aimed at manufacturing conductive metal nanowires to the current fabrication of various nanostructures for applications in areas as diverse as nanolithography, energy conversion and storage, catalysis, sensing, and biomedical engineering. To this, our aim here was to present a comprehensive review to summarize the research activities on DNA metallization that have appeared since the concept was first proposed in 1998. We start with a brief presentation of the basic knowledge of DNA and its unique advantages in the template-directed growth of metal nanomaterials, followed by providing a systematic summary of the various synthetic methods developed to date to deposit metals on DNA scaffolds. Then, the leverage of DNAs with different sequences, conformations, and structures for tuning the synthesis of feature-rich metal nanostructures is discussed. Afterwards, the discussion is divided around the applications of these metal nanomaterials in the fields mentioned above, wherein the key role DNA metallization plays in enabling high performance is emphasized. Finally, the current status and some future prospects and challenges in this field are summarized. As such, this review would be of great interest to promote the further development of DNA metallization by attracting researchers from various communities, including chemistry, biology, physiology, material science, and nanotechnology as well as other disciplines.

11.
Angew Chem Int Ed Engl ; 58(45): 16236-16242, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31456332

RESUMEN

Nanozymes have emerged as a new generation of antibiotics with exciting broad-spectrum antimicrobial properties and negligible biotoxicities. However, their antibacterial efficacies are unsatisfactory due to their inability to trap bacteria and their low catalytic activity. Herein, we report nanozymes with rough surfaces and defect-rich active edges. The rough surface increases bacterial adhesion and the defect-rich edges exhibit higher intrinsic peroxidase-like activity compared to pristine nanozymes due to their lower adsorption energies of H2 O2 and desorption energy of OH*, as well as the larger exothermic process for the whole reaction. This was demonstrated using drug-resistant Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus in vitro and in vivo. This strategy can be used to engineer nanozymes with enhanced antibacterial function and will pave a new way for the development of alternative antibiotics.


Asunto(s)
Antibacterianos/farmacología , Disulfuros/química , Infecciones por Escherichia coli/tratamiento farmacológico , Escherichia coli/efectos de los fármacos , Molibdeno/química , Peroxidasas/química , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Animales , Antibacterianos/química , Infecciones por Escherichia coli/microbiología , Peróxido de Hidrógeno/metabolismo , Ratones , Ratones Endogámicos BALB C , Infecciones Estafilocócicas/microbiología
12.
J Nanosci Nanotechnol ; 18(4): 3012-3017, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29442988

RESUMEN

Silver nanowires with high yield, uniform size and high aspect ratio were successfully synthesized by a simple and effective polyol method under low temperature and quiescent conditions, adopting CuCl2·2H2O as the nucleation control agent for the first time. The synthesized silver nanowires were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-Vis diffuse reflectance spectroscopy (DRS). The results indicate that the silver nanowires were composed of face-centered cubic structure of pure metallic silver with high crystallinity. And the silver nanowires have an average length of 80~100 µm and an average diameter of 40~80 nm. Thus, the aspect ratio of the nanowires was greater than 1000. In addition, the influence on the morphology and structure of the silver nanowires were investigated for reaction temperature, mole ratio of PVP:AgNO3, molecular weight of PVP and mole ratio of control agent CuCl2 · 2H2O:AgNO3. Finally, the optimum reaction condition were obtained for the preparation of the silver nanowires with high aspect ratio.

13.
Chemistry ; 23(54): 13518-13524, 2017 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-28741846

RESUMEN

Skin cancers caused by UV irradiation have been a major public health problem. One simple and effective way to avoid the above detrimental effects is the use of UV-protective sunscreens. However, there has been considerable concern with the issue of the production of reactive oxygen species (ROS) through the photodegradation of commercial UV filters. Herein, for the first time, it is reported that the integration of ZnO nanoparticles and CeOx nanoparticles into hollow microspheres (ZnO/CeOx HMS) could provide broad-spectrum UV protection and scavenge generated ROS under UV irradiation. Benefiting from the cooperative effect of the hollow structure and the antioxidative activity of CeOx , ROS generated under UV irradiation could be confined to a limited space and effectively conversion into nontoxic molecules is catalyzed as a consequence of increased collision frequency. Therefore, both primary, direct UV-induced damage and secondary ROS toxicity could be greatly reduced.


Asunto(s)
Especies Reactivas de Oxígeno/metabolismo , Protectores Solares/química , Rayos Ultravioleta , Animales , Catálisis , Supervivencia Celular/efectos de los fármacos , Cerio/química , Rojo Congo/química , Femenino , Citometría de Flujo , Células HEK293 , Humanos , Nanopartículas del Metal/química , Ratones , Microscopía Fluorescente , Fotólisis , Especies Reactivas de Oxígeno/química , Piel/patología , Piel/efectos de la radiación , Protectores Solares/farmacología , Óxido de Zinc/química
14.
Clin Lab ; 60(4): 587-97, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24779292

RESUMEN

BACKGROUND: Primary hepatic carcinoma (PHC) is currently one of the most common worldwide causes of cancer death. Golgi protein 73 (GP73) has been proposed as potential diagnostic marker. However, it is controversial because of inconsistent diagnostic accuracy in different studies. The aim of this study was to assess the diagnostic accuracy of GP73 for PHC. METHODS: All the studies relating to the diagnostic accuracy of GP73 for patients with PHC from 1978 to January 2013 were collected. Methodological quality was assessed by Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). The overall diagnostic sensitivity, specificity, and area under the receiver operating characteristic curve were used to evaluate the diagnostic accuracy of GP73 using Meta-DiSc statistical software. RESULTS: Altogether 5,637 subjects were included in the 25 selected studies. The sensitivity and specificity (95% confidence interval) of GP73 was 0.75 (0.73-0.76) and 0.84 (0.83 - 0.86), respectively. The area under the summary receiver operating characteristic curve (AUC) and Q* index of GP73 was 0.8616 and 0.8021. CONCLUSIONS: Serum GP73 has a relatively high diagnostic accuracy in primary hepatic carcinoma with better sensitivity and high specificity than AFP.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma/sangre , Neoplasias Hepáticas/sangre , Proteínas de la Membrana/sangre , Ensayo de Inmunoadsorción Enzimática , Humanos , Curva ROC , alfa-Fetoproteínas/metabolismo
15.
Nanoscale Horiz ; 9(7): 1070-1071, 2024 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-38695198

RESUMEN

This article highlights the recent work of Castagnola, Armirotti, et al. (Nanoscale Horiz., 2024, https://doi.org/10.1039/D3NH00510K) on demonstrating that the widespread use of 10% fetal bovine serum in an in vitro assay cannot recapitulate the complexity of in vivo systemic administration.


Asunto(s)
Nanoestructuras , Corona de Proteínas , Nanoestructuras/química , Humanos , Corona de Proteínas/química , Animales , Bovinos
16.
Exploration (Beijing) ; 4(1): 20230019, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38854493

RESUMEN

Calcium ions (Ca2+) are indispensable and versatile metal ions that play a pivotal role in regulating cell metabolism, encompassing cell survival, proliferation, migration, and gene expression. Aberrant Ca2+ levels are frequently linked to cell dysfunction and a variety of pathological conditions. Therefore, it is essential to maintain Ca2+ homeostasis to coordinate body function. Disrupting the balance of Ca2+ levels has emerged as a potential therapeutic strategy for various diseases, and there has been extensive research on integrating this approach into nanoplatforms. In this review, the current nanoplatforms that regulate Ca2+ homeostasis for cancer therapy are first discussed, including both direct and indirect approaches to manage Ca2+ overload or inhibit Ca2+ signalling. Then, the applications of these nanoplatforms in targeting different cells to regulate their Ca2+ homeostasis for achieving therapeutic effects in cancer treatment are systematically introduced, including tumour cells and immune cells. Finally, perspectives on the further development of nanoplatforms for regulating Ca2+ homeostasis, identifying scientific limitations and future directions for exploitation are offered.

17.
Life (Basel) ; 14(2)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38398744

RESUMEN

This study aimed to investigate the morphological characteristics of fruits and seeds from Diptychocarpus strictus, a plant species inhabiting the cold desert pastoral area of China. Furthermore, this study sought to evaluate the germination potential of these seeds following digestion by sheep. This study employed the sheep rumen fistula method to simulate rumen digestion at various time intervals. Subsequently, an in vitro simulation method was utilized to simulate true gastric and intestinal digestion after rumen digestion. Paper germination tests were then conducted to assess the impact of the digestive process on the heteromorphic seed morphology and germination. During rumen digestion, the seeds were protected by wide wings. The results revealed a highly significant negative correlation (p < 0.01) between seed wing length and digestion time. Post-rumen digestion, variations in the germination rate among seeds from fruits at different locations were observed. Indicators, such as germination rate, exhibited a highly significant negative correlation with rumen digestion time (p < 0.01). In vitro simulated digestion tests demonstrated that Diptychocarpus strictus seeds retained their ability to germinate even after complete digestion within the livestock's digestive tract. The polymorphic nature of Diptychocarpus strictus seeds, coupled with their capacity to survive and germinate through the digestive tract, facilitates the spread of these seeds. This finding has implications for mitigating desert grassland degradation and promoting sustainable ecological development.

18.
Adv Mater ; 36(7): e2306583, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37713652

RESUMEN

Brain diseases, such as brain tumors, neurodegenerative diseases, cerebrovascular diseases, and brain injuries, are caused by various pathophysiological changes, which pose a serious health threat. Brain disorders are often difficult to treat due to the presence of the blood-brain barrier (BBB). Biomimetic nanovesicles (BNVs), including endogenous extracellular vesicles (EVs) derived from various cells and artificial nanovesicles, possess the ability to penetrate the BBB and thus can be utilized for drug delivery to the brain. BNVs, especially endogenous EVs, are widely distributed in body fluids and usually carry various disease-related signal molecules such as proteins, RNA, and DNA, and may also be analyzed to understand the etiology and pathogenesis of brain diseases. This review covers the exhaustive classification and characterization of BNVs and pathophysiological roles involved in various brain diseases, and emphatically focuses on nanotechnology-integrated BNVs for brain disease theranostics, including various diagnosis strategies and precise therapeutic regulations (e.g., immunity regulation, disordered protein clearance, anti-neuroinflammation, neuroregeneration, angiogenesis, and the gut-brain axis regulation). The remaining challenges and future perspectives regarding the nanotechnology-integrated BNVs for the diagnosis and treatment of brain diseases are also discussed and outlined.


Asunto(s)
Biomimética , Neoplasias Encefálicas , Humanos , Encéfalo/metabolismo , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Sistemas de Liberación de Medicamentos
19.
Nanomaterials (Basel) ; 14(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38869589

RESUMEN

Light-induced phase segregation, particularly when incorporating bromine to widen the bandgap, presents significant challenges to the stability and commercialization of perovskite solar cells. This study explores the influence of hole transport layers, specifically poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine (PTAA) and [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz), on the dynamics of phase segregation. Through detailed characterization of the buried interface, we demonstrate that Me-4PACz enhances perovskite photostability, surpassing the performance of PTAA. Nanoscale analyses using in situ Kelvin probe force microscopy and quantitative nanomechanical mapping techniques elucidate defect distribution at the buried interface during phase segregation, highlighting the critical role of substrate wettability in perovskite growth and interface integrity. The integration of these characterization techniques provides a thorough understanding of the impact of the buried bottom interface on perovskite growth and phase segregation.

20.
Bioact Mater ; 34: 414-421, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38292411

RESUMEN

Tumor hypoxia diminishes the effectiveness of traditional type II photodynamic therapy (PDT) due to oxygen consumption. Type I PDT, which can operate independently of oxygen, is a viable option for treating hypoxic tumors. In this study, we have designed and synthesized JSK@PEG-IR820 NPs that are responsive to the tumor microenvironment (TME) to enhance type I PDT through glutathione (GSH) depletion. Our approach aims to expand the sources of therapeutic benefits by promoting the generation of superoxide radicals (O2-.) while minimizing their consumption. The diisopropyl group within PEG-IR820 serves a dual purpose: it functions as a pH sensor for the disassembly of the NPs to release JSK and enhances intermolecular electron transfer to IR820, facilitating efficient O2-. generation. Simultaneously, the release of JSK leads to GSH depletion, resulting in the generation of nitric oxide (NO). This, in turn, contributes to the formation of highly cytotoxic peroxynitrite (ONOO-.), thereby enhancing the therapeutic efficacy of these NPs. NIR-II fluorescence imaging guided therapy has achieved successful tumor eradication with the assistance of laser therapy.

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