Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Small ; : e2308628, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39087380

RESUMO

Vanadium-based phosphate cathode materials (e.g., K3V2(PO4)3) have attracted widespread concentration in cathode materials in potassium-ion batteries owing to their stable structure but suffer from low capacity and poor conductivity. In this work, an element doping strategy is applied to promote its electrochemical performance so that K3.2V2.8Mn0.2(PO4)4/C is prepared via a simple sol-gel method. The heterovalent Mn2+ is introduced to stimulated multiple electron reactions to improve conductivity and capacity, as well as interlayer spacing. Galvanostatic intermittent titration technique (GITT) and in situ X-ray diffraction results further confirm that Mn-doping in the original electrode can obtain superior electrode process kinetics and structural stability. The prepared K3.2V2.8Mn0.2(PO4)4/C exhibits a high-capacity retention of 80.8% after 1 500 cycles at 2 C and an impressive rate capability, with discharge capacities of 87.6 at 0.2 C and 45.4 mA h g-1 at 5 C, which is superior to the majority of reported vanadium-based phosphate cathode materials. When coupled K3.2V2.8Mn0.2(PO4)4/C cathode with commercial porous carbon (PC) anode as the full cell, a prominent energy density of 175 Wh kg-1 is achieved based on the total active mass. Overall, this study provides an effective strategy for meliorating the cycling stability and capacity of the polyanion cathodes for KIB.

2.
Heliyon ; 10(7): e28874, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38623255

RESUMO

Objective: Here we aimed to explore the differences in individual gray matter (GM) networks at baseline in mild cognitive impairment patients who converted to Alzheimer's disease (AD) within 3 years (MCI-C) and nonconverters (MCI-NC). Materials and methods: Data from 461 MCI patients (180 MCI-C and 281 MCI-NC) were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI). For each subject, a GM network was constructed using 3D-T1 imaging and the Kullback-Leibler divergence method. Gradient and topological analyses of individual GM networks were performed, and partial correlations were calculated to evaluate relationships among network properties, cognitive function, and apolipoprotein E (APOE) €4 alleles. Subsequently, a support vector machine (SVM) model was constructed to discriminate the MCI-C and MCI-NC patients at baseline. Results: The gradient analysis revealed that the principal gradient score distribution was more compressed in the MCI-C group than in the MCI-NC group, with scores for the left lingual gyrus, right fusiform gyrus and left middle temporal gyrus being increased in the MCI-C group (p < 0.05, FDR corrected). The topological analysis showed significant differences in nodal efficiency in four nodes between the two groups. Furthermore, the regional gradient scores or nodal efficiency were found to be significantly related to the neuropsychological test scores, and the left middle temporal gyrus gradient scores were positively associated with the number of APOE €4 alleles (r = 0.192, p = 0.002). Ultimately, the SVM model achieved a balanced accuracy of 79.4% in classifying MCI-C and MCI-NC patients (p < 0.001). Conclusion: The whole-brain GM network hierarchy in the MCI-C group was more compressed than that in the MCI-NC group, suggesting more serious cognitive impairments in the MCI-C group. The left middle temporal gyrus gradient scores were related to both cognitive function and APOE €4 alleles, thus serving as potential biomarkers distinguishing MCI-C from MCI-NC at baseline.

3.
Biomimetics (Basel) ; 9(4)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38667260

RESUMO

Precise morphology acquisition for the variable wing leading edge is essential for its bio-inspired adaptive control. Therefore, this study proposes a morphological reconstruction method for the variable wing leading edge, utilizing the node curvature vectors-based curvature propagation method (NCV-CPM). By establishing a strain-arc curvature function, the method fundamentally mitigates the impact of surface curvature angle on curvature computation accuracy at sensing points. We introduce a technique that uses high-order curvature fitting functions to determine the curvature vectors of arc segment nodes. This method reduces cumulative errors in curvature computation linked to the linear interpolation-based curvature propagation method (LI-CPM) at unattached sensor positions. Integrating curvature-strain functions aids in wing leading-edge strain field reconstruction, supporting structural health monitoring. Additionally, a particle swarm algorithm optimizes the sensing point distribution, reducing network complexity. This study demonstrates significantly enhanced morphological reconstruction accuracy compared to those obtained with conventional LI-CPM.

4.
Nano Lett ; 24(11): 3484-3489, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38456741

RESUMO

A carbon nanotube (CNT) may facilitate near-frictionless water transport within it. In this work, we elucidate the slip flow characteristics for a CNT embedded in a silicon nitride matrix using the molecular dynamics (MD) method. We reveal that the wetting transparency of a CNT, the transmission of the membrane matrix wetting property over a CNT, cannot be ignored. Due to the effect of CNT wetting transparency, the orientation flip behavior of water molecules should be the primary cause of the entrance and exit losses, which is a dominant factor influencing the interfacial friction coefficient for the thin CNT membrane. The relationship between the friction coefficient and pore size follows a logarithmic function, which agrees well with the reported experimental data. Our findings bridge the gap between the MD prediction and experimental observation for water transport in a CNT membrane and provide a clear understanding of the mechanism behind its ultrafast flow performance.

5.
Antioxidants (Basel) ; 13(2)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38397739

RESUMO

This study aims to investigate the impact of dietary supplementation with selenium yeast (SeY) and glycerol monolaurate (GML) on the transfer of antioxidative capacity between the mother and fetus during pregnancy and its underlying mechanisms. A total of 160 sows with similar body weight and parity of 3-6 parity sows were randomly and uniformly allocated to four groups (n = 40) as follows: CON group, SeY group, GML group, and SG (SeY + GML) group. Animal feeding started from the 85th day of gestation and continued to the day of delivery. The supplementation of SeY and GML resulted in increased placental weight and reduced lipopolysaccharide (LPS) levels in sow plasma, placental tissues, and piglet plasma. Furthermore, the redox balance and inflammatory markers exhibited significant improvements in the plasma of sows fed with either SeY or GML, as well as in their offspring. Moreover, the addition of SeY and GML activated the Nrf2 signaling pathway, while downregulating the expression of pro-inflammatory genes and proteins associated with inflammatory pathways (MAPK and NF-κB). Vascular angiogenesis and nutrient transportation (amino acids, fatty acids, and glucose) were upregulated, whereas apoptosis signaling pathways within the placenta were downregulated with the supplementation of SeY and GML. The integrity of the intestinal and placental barriers significantly improved, as indicated by the increased expression of ZO-1, occludin, and claudin-1, along with reduced levels of DLA and DAO with dietary treatment. Moreover, supplementation of SeY and GML increased the abundance of Christensenellaceae_R-7_group, Clostridium_sensus_stricto_1, and Bacteroidota, while decreasing levels of gut microbiota metabolites LPS and trimethylamine N-oxide. Correlation analysis demonstrated a significant negative relationship between plasma LPS levels and placental weight, oxidative stress, and inflammation. In summary, dietary supplementation of SeY and GML enhanced the transfer of antioxidative capacity between maternal-fetal during pregnancy via gut-placenta axis through modulating sow microbiota composition.

6.
Adv Sci (Weinh) ; 11(14): e2306936, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38298088

RESUMO

PtII based organometallic photosensitizers (PSs) have emerged as novel potent photodynamic inactivation (PDI) reagents through their enhanced intersystem crossing (ISC) processes. Currently, few PtII PSs have been investigated as antibacterial materials, with relatively poor performances reported and with structure-activity relationships not well described. Herein, a pair of configurational isomers are reported of Bis-BODIPY (4,4-difluoro-boradizaindacene) embedded PtII PSs. The cis-isomer (cis-BBP) displayed enhanced 1O2 generation and better bacterial membrane anchoring capability as compared to the trans-isomer (trans-BBP). The effective PDI concentrations (efficiency > 99.9%) for cis-BBP in Acinetobacter baumannii (multi-drug resistant (MDR)) and Staphylococcus aureus are 400 nM (12 J cm-2) and 100 nM (18 J cm-2), respectively; corresponding concentrations and light doses for trans-BBP in the two bacteria are 2.50 µM (30 J cm-2) and 1.50 µM (18 J cm-2), respectively. The 50% and 90% minimum inhibitory concentration (MIC50 and MIC90) ratio of trans-BBP to cis-BBP is 22.22 and 24.02 in A. baumannii (MDR); 21.29 and 22.36 in methicillin resistant S. aureus (MRSA), respectively. Furthermore, cis-BBP displays superior in vivo antibacterial performance, with acceptable dark and photoinduced cytotoxicity. These results demonstrate cis-BBP is a robust light-assisted antibacterial reagent at sub-micromolecular concentrations. More importantly, configuration of PtII PSs should be an important issue to be considered in further PDI reagents design.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Fármacos Fotossensibilizantes/farmacologia , Relação Estrutura-Atividade , Antibacterianos/farmacologia
7.
Materials (Basel) ; 17(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255527

RESUMO

Magnesium slag is a type of industrial solid waste produced during the production of magnesium metal. In order to gain a deeper understanding of the structure of magnesium slag, the composition and microstructure of magnesium slag were investigated by using characterization methods such as X-ray fluorescence, particle size analysis, X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. In addition, the state of Si occurrence in magnesium slag was analyzed using a solid-state nuclear magnetic resonance technique in comparison with granulated blast furnace slag. An inductively coupled plasma-optical emission spectrometer and scanning electron microscope with energy dispersive X-ray spectroscopy were used to characterize their cementitious behavior. The results show that the chemical composition of magnesium slag mainly includes 54.71% CaO, 28.66% SiO2 and 11.82% MgO, and the content of Al2O3 is much lower than that of granulated blast furnace slag. Compared to granulated blast furnace slag, magnesium slag has a larger relative bridging oxygen number and higher [SiO4] polymerization degree. The cementitious activity of magnesium slag is lower compared to that of granulated blast furnace slag, but it can replace part of the cement to obtain higher compressive strength. Maximum compressive strength can be obtained when the amount of magnesium slag replacing cement is 20%, where the 28-day compressive strength can be up to 45.48 MPa. This work provides a relatively comprehensive analysis of the structural characteristics and cementitious behavior of magnesium slag, which is conducive to the promotion of magnesium slag utilization.

8.
Chin Med J (Engl) ; 137(1): 21-33, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37592858

RESUMO

ABSTRACT: γδ T cells are a kind of innate immune T cell. They have not attracted sufficient attention because they account for only a small proportion of all immune cells, and many basic factors related to these cells remain unclear. However, in recent years, with the rapid development of tumor immunotherapy, γδ T cells have attracted increasing attention because of their ability to exert cytotoxic effects on most tumor cells without major histocompatibility complex (MHC) restriction. An increasing number of basic studies have focused on the development, antigen recognition, activation, and antitumor immune response of γδ T cells. Additionally, γδ T cell-based immunotherapeutic strategies are being developed, and the number of clinical trials investigating such strategies is increasing. This review mainly summarizes the progress of basic research and the clinical application of γδ T cells in tumor immunotherapy to provide a theoretical basis for further the development of γδ T cell-based strategies in the future.


Assuntos
Neoplasias , Receptores de Antígenos de Linfócitos T gama-delta , Humanos , Imunoterapia Adotiva , Linfócitos T , Imunoterapia , Neoplasias/terapia
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1013509

RESUMO

@#[摘 要] γδT细胞是一类表达γδTCR异源二聚体的特殊固有免疫T细胞。过去,缺乏对其全面系统的基础研究,在其发育、分化、增殖、活化、效应和耗竭等所有环节仍有很多问题尚不清楚。然而,因为成熟的γδT细胞优势定植于皮肤、消化道、呼吸道、生殖道等肿瘤高发的黏膜组织,能以MHC非限制性的方式直接识别和杀伤多种肿瘤细胞,在肿瘤免疫治疗领域具有不可替代的优势,近年来其应用异军突起,发展迅速,也因此反过来促进了基础研究的深入,取得了一些亮眼的进展。本文对2023年γδT细胞在肿瘤免疫治疗领域的重大进展进行述评,主要集中在γδT细胞肿瘤抗原识别机制、肿瘤微环境中γδT细胞的功能调控、γδT细胞抗肿瘤细胞毒活性的机制、新型基于γδT细胞的肿瘤免疫治疗协同增效策略四个方面,以期推动γδT细胞在肿瘤免疫治疗领域的进一步发展,为临床γδT细胞应用协同增效的策略提供新的思路。

10.
Natl Sci Rev ; 10(10): nwad200, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37671320

RESUMO

Photosynthetic energy conversion for high-energy chemicals generation is one of the most viable solutions in the quest for sustainable energy towards carbon neutrality. Microalgae are fascinating photosynthetic organisms, which can directly convert solar energy into chemical energy and electrical energy. However, microalgal photosynthetic energy has not yet been applied on a large scale due to the limitation of their own characteristics. Researchers have been inspired to couple microalgae with synthetic materials via biomimetic assembly and the resulting microalgae-material hybrids have become more robust and even perform new functions. In the past decade, great progress has been made in microalgae-material hybrids, such as photosynthetic carbon dioxide fixation, photosynthetic hydrogen production, photoelectrochemical energy conversion and even biochemical energy conversion for biomedical therapy. The microalgae-material hybrid offers opportunities to promote artificially enhanced photosynthesis research and synchronously inspires investigation of biotic-abiotic interface manipulation. This review summarizes current construction methods of microalgae-material hybrids and highlights their implication in energy and health. Moreover, we discuss the current problems and future challenges for microalgae-material hybrids and the outlook for their development and applications. This review will provide inspiration for the rational design of the microalgae-based semi-natural biohybrid and further promote the disciplinary fusion of material science and biological science.

11.
Acta Diabetol ; 60(10): 1405-1415, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37380727

RESUMO

AIMS: To examined the relationship between fear of hypoglycemia and certain variables in people with type 2 diabetes mellitus (T2DM) based on the Capability, Opportunity, Motivation, and Behavior model, combined with the context unique to people with diabetes to provide a basis for developing targeted nursing interventions. METHODS: In this cross-sectional study, 212 people with T2DM were recruited from February 2021 to July 2021. Data were collected using the Hypoglycaemia Fear Survey, Gold score, Patient Assessment of Chronic Illness Care (PACIC) scale and Diabetic Self-Management Attitudes Scale. Multiple linear regression analysis was performed to determine the predictors of fear of hypoglycemia using SPSS 26.0. RESULTS: The mean fear of hypoglycemia score was 74.88 ± 18.28 (range: 37.00-132.00). In people with T2DM, the frequency of blood glucose monitoring, the frequency of hypoglycemia in the past half-year, degree of understanding of hypoglycemia, impaired awareness of hypoglycemia, PACIC, and self-management attitude of diabetes were the influencing factors of fear of hypoglycemia (adjusted R2 = 0.560, F[21,190] = 13.800, P < 0.001). These variables explained 56.0% of the variance in the fear of hypoglycemia. CONCLUSIONS: The level of fear of hypoglycemia in people with T2DM was relatively high. In addition to paying attention to the disease characteristics of people with T2DM, medical staff should also pay attention to patients' own perception and handling ability of disease and hypoglycemia, attitude toward self-management behavior and external environment support, all of which have a positive effect on improving the fear of hypoglycemia in people with T2DM, optimizing the self-management level and improving quality of life.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemia , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Estudos Transversais , Qualidade de Vida , Motivação , Automonitorização da Glicemia , Glicemia , Medo
12.
J Mater Chem B ; 11(21): 4752-4762, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37183453

RESUMO

Surgical resection is the main method for oral tongue squamous cell carcinoma (OTSCC) treatment. However, the oral physiological function and aesthetics may be seriously damaged during the operation with a high risk of recurrence. Therefore, it is important to develop an alternative strategy with precise guidance for OTSCC treatment. Herein, multifunctional Au/Mn nanodots (NDs) are designed and synthesized. They can perform multimodal bioimaging, including computed tomography (CT) and magnetic resonance imaging (MRI) simultaneously, and exhibit bright near-infrared fluorescence imaging (FI) for navigation, and even integrate photothermal therapy (PTT) property. The localization of OTSCC relies on visual and tactile cues of surgeons while lacking noninvasive pretreament labeling and guidance. Au/Mn NDs provide CT/MRI imaging, giving two means of accurate positioning pretherapy. Meanwhile, the fluorescence of the Au/Mn NDs in the near-infrared region (NIR) is beneficial for noninvasive labeling and intuitive observation with the naked eye to determine the tumor boundary during PTT. Further, Au/Mn NDs showed excellent results in ablating tumors in vivo. Above all, the Au/Mn NDs provide a key platform for multimodal bioimaging and PTT in a single nanoagent, which demonstrated attractive performance for OTSCC treatment.


Assuntos
Carcinoma de Células Escamosas , Neoplasias da Língua , Humanos , Neoplasias da Língua/diagnóstico por imagem , Neoplasias da Língua/terapia , Terapia Fototérmica , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X
13.
Adv Mater ; 35(34): e2109171, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36333118

RESUMO

The ability to perform nanometer-scale optical imaging and spectroscopy is key to deciphering the low-energy effects in quantum materials, as well as vibrational fingerprints in planetary and extraterrestrial particles, catalytic substances, and aqueous biological samples. These tasks can be accomplished by the scattering-type scanning near-field optical microscopy (s-SNOM) technique that has recently spread to many research fields and enabled notable discoveries. Herein, it is shown that the s-SNOM, together with scanning probe research in general, can benefit in many ways from artificial-intelligence (AI) and machine-learning (ML) algorithms. Augmented with AI- and ML-enhanced data acquisition and analysis, scanning probe optical nanoscopy is poised to become more efficient, accurate, and intelligent.

14.
ACS Appl Mater Interfaces ; 15(1): 292-308, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36583968

RESUMO

A critical-sized bone defect, which cannot be repaired through self-healing, is a major challenge in clinical therapeutics. The combination of biomimetic hydrogels and nano-hydroxyapatite (nano-HAP) is a promising way to solve this problem by constructing an osteogenic microenvironment. However, it is challenging to generate nano-HAP with a similar morphology and structure to that of natural bone, which limits the improvement of bone regeneration hydrogels. Inspired by our previous works on organic-inorganic cocross-linking, here, we built a strong organic-inorganic interaction by cross-linking periosteum-decellularized extracellular matrix and calcium phosphate oligomers, which ensured the in situ mineralization of bone-like nano-HAP in hydrogels. The resulting biomimetic osteogenic hydrogel (BOH) promotes bone mineralization, construction of immune microenvironment, and angiogenesis improvement in vitro. The BOH exhibited acceleration of osteogenesis in vivo, achieving large-sized bone defect regeneration and remodeling within 8 weeks, which is superior to many previously reported hydrogels. This study demonstrates the important role of bone-like nano-HAP in osteogenesis, which deepens the understanding of the design of biomaterials for hard tissue repair. The in situ mineralization of bone-like nano-HAP emphasizes the advantages of inorganic ionic oligomers in the construction of organic-inorganic interaction, which provides an alternative method for the preparation of advanced biomimetic materials.


Assuntos
Durapatita , Hidrogéis , Durapatita/farmacologia , Durapatita/química , Hidrogéis/farmacologia , Hidrogéis/química , Biomimética , Regeneração Óssea , Osteogênese , Periósteo , Aceleração
15.
ACS Appl Mater Interfaces ; 14(30): 34377-34387, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35878314

RESUMO

Osteosarcoma is difficult to be resected through surgical operations without damage to the bone matrix, while chemotherapy and radiotherapy induce inevitable systemic injury. It is still a major challenge to develop a novel treatment suitable for the complex anatomical structure of the bone. Herein, inspired by lotus seedpods, injectable hydrogels with long-term retention for synergistic osteosarcoma treatment were developed. Gold nanoclusters (GNCs) with strong fluorescence (FL) and computed tomography (CT) imaging effects represented the lotus seeds. The oxidized hyaluronic acid (HA-ALD) chain resembled the stem. HA-ALD and GNCs form crosslinking-assembled hydrogels abbreviated as HG-CAHs through dynamic amide bonds. Compared with DNA-, pH-, and light-mediated assembly, this in situ method induces enhanced photothermal therapy (PTT) ability, ensures high biocompatibility, and retains the imaging function of GNCs, which contribute to lighting up osteosarcoma persistently for further diagnosis and treatment. In addition, the HG-CAHs with outstanding mechanical properties are similar to the lotus seedpods with supportive force and a typical porous structure. They are favorable for the local pH- and near-infrared (NIR)-responsive release of doxorubicin (Dox) owing to the acidic osteosarcoma microenvironment and the Brownian movement. The HG-CAHs ablate osteosarcoma efficiently and reduce metabolic toxicity significantly, which will aid in the development of a new generation of osteosarcoma treatments.


Assuntos
Hidrogéis , Osteossarcoma , Doxorrubicina , Ouro/química , Humanos , Ácido Hialurônico/química , Hidrogéis/química , Hidrogéis/uso terapêutico , Imagem Multimodal/métodos , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/tratamento farmacológico , Microambiente Tumoral
16.
Adv Healthc Mater ; 11(14): e2200516, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35537701

RESUMO

Diabetic wound is a significant challenge for clinical treatment with high morbidity and mortality. Plenty of hydrogels with good biocompatibility have been widely used in diabetic wound healing. However, most of them cannot be directly absorbed and utilized by the wounds, which prolongs the regeneration time. Here a new type of healing hydrogel is developed that is based on histidine, a natural dietary essential amino acid that is significant for tissue formation. The amino acid is cross-linked with zinc ions (Zn2+ ) and sodium alginate (SA) via dynamic coordinate and hydrogen bonds, respectively, forming a histidine-SA-Zn2+ (HSZH) hydrogel with good injectable, adhesive, biocompatible, and antibacterial properties. Application of this dual-dynamic-bond cross-linked HSZH hydrogel accelerates the migration and angiogenesis of skin-related cells in vitro. Furthermore, it significantly promotes the healing of infected diabetic wounds in vivo and uniquely allows a full repair of wounds within ≈13 days, while ≈27 days are required for the healing process of the control group. This work provides a new strategy for designing wound dressing materials, that weakly cross-linked material based on tissue-friendly micromolecules can heal the wounds more efficiently than highly cross-linked materials based on long-chain polymers.


Assuntos
Diabetes Mellitus , Infecção dos Ferimentos , Alginatos , Histidina , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Cicatrização
17.
Macromol Rapid Commun ; 43(10): e2200034, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35332623

RESUMO

Cancer remains a formidable global problem with a high mortality rate. There are many effective anti-cancer drugs in clinical use, among which paclitaxel (PTX) has good effects on non-small cell lung cancer, ovarian cancer, and breast cancer. However, when applied to the clinic, PTX still has many limitations, such as poor water solubility, drug resistance, and side effects on healthy tissues. A gold nanodots-paclitaxel-polylysine (AuNDs-PTX-PLL) core-shell nano-system of integrated diagnosis and treatment is constructed to achieve intelligent responsive drug delivery. On the one hand, the problem of poor water-solubility and drug resistance of PTX are solved. On the other hand, the nano-system has an excellent intelligent response effect. Drugs can only be released in the weakly acidic environment of the tumor, which reduces the damage and side effects to normal tissues. Moreover, the nano-system can be used for real-time tracking and auxiliary diagnosis for the tumor through the multi-mode imaging mode, such as fluorescence, photoacoustic, and computed tomography to achieve accurate visualization. The photothermal effect of AuNDs is beneficial to promote the release of drugs. The nano-system integrates multi-mode imaging, chemotherapy, intelligent drug release in tumor weakly acidic environment, and has excellent practical application prospects in tumor diagnosis and treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Ouro , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Água
18.
Talanta ; 241: 123241, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35144114

RESUMO

Spinal cord injury is one of the most devastating complications of spinal surgery, often resulting in numbness, pain or paralysis. Minor injuries in the spinal cord are hard to be identified and existing imaging modalities are unable to provide intraoperative monitoring. Monitoring pathological change at the site of injury is a key factor in staging and treatment decision making as well as prognosis of spinal cord injury. Herein, we offer the fluorescence imaging with intraoperative visualization and detection accuracy for bioimaging to resolve the problem. A novel red fluophore AuNDs caped with glutathione is prepared, which exhibits some advantages such as ultra-small size, negligible biotoxicity, superior water solubility and great biocompatibility. AuNDs fluorophore especially exhibit both of a remarkable photoluminescence stability and high attenuation coefficient to X-rays. In addition, AuNDs can be used as CT contrast agent for spinal cord, which avoid the high toxicity and weak CT signal of traditional iodine contrast. After intradural injection into the spinal cord, AuNDs are transported through the flow of cerebrospinal fluid and bound to the spinal cord parenchyma. not only the bioimage of the entire spinal cord can be achieved as quick as 15 min, but they are also particularly beneficial to long-term imaging of complex physiological environments in vivo, with negligible quenching. Comparing from the bright red fluorescence in adjacent normal spinal cord sites, there is almost no fluorescence in spinal cord at the areas of the injury. We suggest that AuNDs are unable to enter the injury sites of necrosis and ischemia, which promote a different contrast imaging from the normal one. The bright red fluorescence of the AuNDs significantly overcome the restriction of the blue autofluorescence of the biological tissues, providing a clear boundary for observation of the thin spinal cord injury. As a result, we developed the AuNDs with fluorescent and CT dual-mode bioimaging capability to clearly and effectively diagnose spinal cord injury, which are expected to provide a novel visualization imaging regent for clinical use.


Assuntos
Ouro , Traumatismos da Medula Espinal , Corantes Fluorescentes , Humanos , Imagem Óptica/métodos , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/metabolismo
19.
Adv Mater ; 34(9): e2107523, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34962676

RESUMO

The development of environmentally friendly plastics is critical to ensure sustainable development. In contrast to polymer plastics derived from petrochemicals, inorganic minerals, which are the most abundant matter in Earth's crust, are environmentally friendly. However, the brittleness of these minerals limits their applications as plastics. Here, because of the advantages of both biomineralization and inorganic ionic polymerization, the calcium phosphate (CaP, a typical geological and biological mineral) oligomers are used for biomimetic mineralization under the regulation of polyvinyl alcohol and sodium alginate, resulting in flexible CaP nanofibers with periodic structural defects. The assembly of CaP nanofibers produces a hierarchically structured bulk hybrid mineral (HM), which overcomes the intrinsic brittleness of minerals and exhibits plasticity characteristics. HM exhibits better hardness and thermostability than classical polymer plastics due to its dominant mineral composition. Notably, HM is environmentally friendly and degradable in nature, as it can potentially participate in geological cycles, indicating that this material is an optimal plastic substitute. The construction of periodic structural defects within flexible minerals expands the current understanding of materials science.

20.
Adv Healthc Mater ; 11(2): e2101723, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34699694

RESUMO

Current macrocapsules with semipermeable but immunoprotective polymeric membranes are attractive devices to achieve the purpose of immunoisolation, however, their ability to allow diffusion of essential nutrients and oxygen is limited, which leads to a low survival rate of encapsulated cells. Here, a novel method is reported by taking advantage of thermotropic liquid crystals, sodium laurylsulfonate (SDS) liquid crystals (LCs), and rod-like crystal fragments (LCFs) to develop engineered alginate hydrogels with rod-like channels. This cell-isolation capsule with an engineered alginate hydrogel-wall allows small molecules, large molecules, and bacteria to diffuse out from the capsules freely but immobilizes the encapsulated cells inside and prevents cells in the microenvironment from moving in. The encapsulated cells show a high survival rate with isolation of host immune cells and long-term growth with adequate nutrients and oxygen supply. In addition, by sharing and responding to the normal molecular and vesicular microenvironment (NMV microenvironment), encapsulated cancer cells display a transition from tumorous phenotypes to ductal features of normal epithelial cells. Thus, this device will be potentially useful for clinical application in cell therapy by secreting molecules and for establishment of patient-derived xenograft (PDX) models that are often difficult to achieve for certain types of tumors, such as prostate cancer.


Assuntos
Hidrogéis , Neoplasias , Alginatos/química , Cápsulas/química , Difusão , Humanos , Hidrogéis/química , Masculino , Neoplasias/tratamento farmacológico , Polímeros
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...