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1.
ACS Nano ; 18(32): 21112-21124, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39094075

RESUMO

The precise assessment of vascular heterogeneity in brain tumors is vital for diagnosing, grading, predicting progression, and guiding treatment decisions. However, currently, there is a significant shortage of high-resolution imaging approaches. Herein, we propose a contrast-enhanced susceptibility-weighted imaging (CE-SWI) utilizing the minimalist dextran-modified Fe3O4 nanoparticles (Dextran@Fe3O4 NPs) for ultrahigh-resolution mapping of vasculature in brain tumors. The Dextran@Fe3O4 NPs are prepared via a facile coprecipitation method under room temperature, and exhibit small hydrodynamic size (28 nm), good solubility, excellent biocompatibility, and high transverse relaxivity (r2*, 159.7 mM-1 s-1) under 9.4 T magnetic field. The Dextran@Fe3O4 NPs-enhanced SWI can increase the contrast-to-noise ratio (CNR) of cerebral vessels to 2.5 times that before injection and achieves ultrahigh-spatial-resolution visualization of microvessels as small as 0.1 mm in diameter. This advanced imaging capability not only allows for the detailed mapping of both enlarged peritumoral drainage vessels and the intratumoral microvessels, but also facilitates the sensitive imaging detection of vascular permeability deterioration in a C6 cells-bearing rat glioblastoma model. Our proposed Dextran@Fe3O4 NPs-enhanced SWI provides a powerful imaging technique with great clinical translation potential for the precise theranostics of brain tumors.


Assuntos
Neoplasias Encefálicas , Dextranos , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Animais , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Dextranos/química , Ratos , Meios de Contraste/química , Humanos , Linhagem Celular Tumoral , Tamanho da Partícula
2.
Food Chem ; 460(Pt 2): 140487, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39067427

RESUMO

The monitoring of antioxidant capacity is very important to evaluate the quality of antioxidant foods or drugs for market regulation. Herein, dechlorination treatment of waste PVC/scrap irons were conducted in subcritical water to obtain carbon-based Fe composites (CM-Fe-dPVC) with peroxidase-like activity. The electron bonding of C 2p and Fe 3d orbital led to strong electron migration ability. CM-Fe-dPVC exhibited excellent activity of simulated peroxidase. Vitamin C (VC) and CM-Fe-dPVC had competitive behaviors on •OH generation in TMB oxidation reaction. A portable paper based colorimetric test kit was developed for monitoring total antioxidant capacity of beverages and pharmaceuticals on the market (with the detection limit of 0.1 µM for Vc). The results of life cycle assessment (LCA) revealed that the proposed strategy had low global warming potential. This research could provide important reference for high value recycling of organic solid wastes.

3.
Small ; : e2401061, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963320

RESUMO

The precise mapping of collateral circulation and ischemic penumbra is crucial for diagnosing and treating acute ischemic stroke (AIS). Unfortunately, there exists a significant shortage of high-sensitivity and high-resolution in vivo imaging techniques to fulfill this requirement. Herein, a contrast enhanced susceptibility-weighted imaging (CE-SWI) using the minimalist dextran-modified Fe3O4 nanoparticles (Fe3O4@Dextran NPs) are introduced for the highly sensitive and high-resolution AIS depiction under 9.4 T for the first time. The Fe3O4@Dextran NPs are synthesized via a simple one-pot coprecipitation method using commercial reagents under room temperature. It shows merits of small size (hydrodynamic size 25.8 nm), good solubility, high transverse relaxivity (r2) of 51.3 mM-1s-1 at 9.4 T, and superior biocompatibility. The Fe3O4@Dextran NPs-enhanced SWI can highlight the cerebral vessels readily with significantly improved contrast and ultrahigh resolution of 0.1 mm under 9.4 T MR scanner, enabling the clear spatial identification of collateral circulation in the middle cerebral artery occlusion (MCAO) rat model. Furthermore, Fe3O4@Dextran NPs-enhanced SWI facilitates the precise depiction of ischemia core, collaterals, and ischemic penumbra post AIS through matching analysis with other multimodal MR sequences. The proposed Fe3O4@Dextran NPs-enhanced SWI offers a high-sensitivity and high-resolution imaging tool for individualized characterization and personally precise theranostics of stroke patients.

4.
Mass Spectrom Rev ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004897

RESUMO

With the development of analytical technologies especially mass spectrometry, metabolomics is becoming increasingly hot in the field of studying antibiotic-bacterial interactions. On the one hand, metabolomics can reveal metabolic perturbations in bacteria in the presence of antibiotics and expose metabolic mechanisms. On the other hand, through in-depth analysis of bacterial metabolic profiles, biomarkers and bioactive secondary metabolites with great potential as drug precursors can be discovered. This review focuses on the experimental workflow of bacterial metabolomics and its application to study the interaction between bacteria and antibiotics. Metabolomics improves the understanding of antibiotic lethality, reveals metabolic perturbations in antibiotic-resistant bacteria, guides the diagnosis and antibiotic treatment of infectious diseases, and aids in the exploration of antibacterial metabolites in nature. Furthermore, current limitations and directions for future developments in this area are discussed.

6.
J Colloid Interface Sci ; 675: 836-847, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39002234

RESUMO

The persistent hurdles of charge rapid recombination, inefficient use of light and utilization of sacrificial reagents have plagued the field of photocatalytic hydrogen evolution (PHE). In this research, tiny MoO2 nanoparticles of 10 nm in diameter were prepared through a straightforward solvothermal approach with a specific ratio of oleylamine and oleic acid as stabilizers. The critical factor in the synthesis process was found to be the ratio of oleylamine to oleic acid. Moreover, a two-phase interface assembly method facilitated the uniform deposition of MoO2 onto CdS nanorods. Due to the localized plasmonic-thermoelectric effect on the surface of MoO2 along with its abundant oxygen vacancies, the composite catalyst exhibited outstanding photo-utilization efficiency and an abundance of active sites. The CdS-MoO2 composite displayed a unique photochemical property in transforming lactic acid into pyruvic acid and generating hydrogen simultaneously. After exposure to artificial sunlight for 4 h, significant values of 4.7 and 3.7 mmol⋅g-1⋅h-1 were achieved for hydrogen production and pyruvic acid formation, respectively, exceeding CdS alone by 3.29 and 4.02-fold, while the selectivity of pyruvic acid was 95.68 %. Furthermore, the S-Scheme electron transport mechanism in the composites was elucidated using Electron Paramagnetic Resonance (EPR) spectroscopy, radical trapping experiments, energy band structure analysis, and the identification of critical intermediates in the process of selective oxidation. This work sheds light on the design and preparation of high-performance photocatalysts for biorefining coupled with efficient hydrogen evolution.

7.
Anal Chim Acta ; 1314: 342803, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38876516

RESUMO

BACKGROUND: The detection of plasticizers in the environment is important to prevent environmental risks and people's health hazards. Improving recycling efficiency of waste PVC still faced challenges. RESULTS: In this work, it was found that solid products from waste PVC/coal gangue dechlorination in subcritical water (dPVC) had strong catalysis activity for luminol-H2O2 chemiluminescence (CL) reaction. Phthalates, common plasticizers, could bond and adsorb on dPVC, which greatly inhibited the luminol-H2O2-dPVC CL reaction. Based on this, a low-cost CL analysis was constructed for the detection of phthalates combinations (PACs) and di-(2-ethylhexyl) phthalate (DEHP) in the environment. The detection limit for PACs and DEHP was 0.048 ng/L and 0.13 ng/L, respectively. Compared with HPLC standard method, the dPVC CL analysis had accuracy and reliability for the detection of phthalates in actual environmental samples. Besides, the results of life cycle assessment (LCA) revealed that dPVC for CL sensing materials had significantly small global warming potential (GWP). SIGNIFICANCE: The use of dPVC for CL sensing not only improved the recycling efficiency of PVC, but also reduced carbon emissions of obtaining CL sensing materials.

8.
Mikrochim Acta ; 191(6): 360, 2024 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819644

RESUMO

A novel in-tube solid-phase microextraction coupled with an ultra-high performance liquid chromatography-mass spectrometry method has been established for simultaneous quantification of three crucial brain biomarkers N-acetylaspartic acid (NAA), N-acetylglutamic acid (NAG), and N-acetylaspartylglutamic acid (NAAG). A polymer monolith with quaternary ammonium as the functional group was designed and exhibited efficient enrichment of target analytes through strong anion exchange interaction. Under the optimized conditions, the proposed method displayed wide linear ranges (0.1-80 nM for NAA and NAG, 0.2-160 nM for NAAG) with good precision (RSDs were lower than 15%) and low limits of detection (0.019-0.052 nM), which is by far the most sensitive approach for NAA, NAG, and NAAG determination. Furthermore, this approach has been applied to measure the target analytes in mouse brain samples, and endogenous NAA, NAG, and NAAG were successfully detected and quantified from only around 5 mg of cerebral cortex, cerebellum, and hippocampus. Compared with existing methods, the newly developed method in the current study provides highest sensitivity and lowest sample consumption for NAA, NAG, and NAAG measurements, which would potentially be utilized in determining and tracking these meaningful brain biomarkers in diseases or treatment processes, benefiting the investigations of pathophysiology and treatment of brain disorders.


Assuntos
Ácido Aspártico , Encéfalo , Dipeptídeos , Microextração em Fase Sólida , Espectrometria de Massas em Tandem , Animais , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Camundongos , Microextração em Fase Sólida/métodos , Encéfalo/metabolismo , Dipeptídeos/análise , Limite de Detecção , Biomarcadores/análise , Masculino , Química Encefálica , Glutamatos
9.
Genome Biol ; 25(1): 116, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715020

RESUMO

BACKGROUND: Structural variations (SVs) have significant impacts on complex phenotypes by rearranging large amounts of DNA sequence. RESULTS: We present a comprehensive SV catalog based on the whole-genome sequence of 1060 pigs (Sus scrofa) representing 101 breeds, covering 9.6% of the pig genome. This catalog includes 42,487 deletions, 37,913 mobile element insertions, 3308 duplications, 1664 inversions, and 45,184 break ends. Estimates of breed ancestry and hybridization using genotyped SVs align well with those from single nucleotide polymorphisms. Geographically stratified deletions are observed, along with known duplications of the KIT gene, responsible for white coat color in European pigs. Additionally, we identify a recent SINE element insertion in MYO5A transcripts of European pigs, potentially influencing alternative splicing patterns and coat color alterations. Furthermore, a Yorkshire-specific copy number gain within ABCG2 is found, impacting chromatin interactions and gene expression across multiple tissues over a stretch of genomic region of ~200 kb. Preliminary investigations into SV's impact on gene expression and traits using the Pig Genotype-Tissue Expression (PigGTEx) data reveal SV associations with regulatory variants and gene-trait pairs. For instance, a 51-bp deletion is linked to the lead eQTL of the lipid metabolism regulating gene FADS3, whose expression in embryo may affect loin muscle area, as revealed by our transcriptome-wide association studies. CONCLUSIONS: This SV catalog serves as a valuable resource for studying diversity, evolutionary history, and functional shaping of the pig genome by processes like domestication, trait-based breeding, and adaptive evolution.


Assuntos
Genoma , Variação Estrutural do Genoma , Animais , Sus scrofa/genética , Polimorfismo de Nucleotídeo Único , Suínos/genética , Mapeamento Cromossômico
10.
J Hazard Mater ; 473: 134538, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38761759

RESUMO

Both sediments and microplastics (MPs) are medias of heavy metals (HMs) in river ecosystems. This study investigated HMs (Mn, Cr, V, As, Cu, Co, Cd, Pb, and Ni) concentration and driving factors for competitive enrichment between hyporheic sediments versus MPs. The medias basic characteristics indicated that the sediments were mostly sand and rich in Fe2O3; three polymer types were identified, with blue, fragment, less than 500 µm being the main types of MPs. The results have shown that the average content of extracted HMs in MPs was much higher than that of the same metals accumulated in sediments. HMs in sediments and MPs reached heavily polluted at some points, among which As and Cd were ecological risks. Electrostatic adsorption and surface complexation, and biofilm-mediated and organic matter complexation were the interaction mechanism of HMs with sediments and MPs. Further, the driving factors affecting the distribution of HMs in the two carriers were analyzed by multivariate statistical analysis. The results demonstrated that carrier characteristics, hydrochemical factors, and the inherent metal load of MPs were the main causes of the high HMs content. These findings improved our understanding of HMs fate and environmental risks across multiple medias.

11.
Oncol Lett ; 27(5): 220, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38586204

RESUMO

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an extremely rare and aggressive tumor with an unknown pathogenesis. Myelofibrosis (MF) is a type of myeloproliferative neoplasm. MF can be secondary to several hematological malignancies, including chronic myeloid leukemia, myelodysplastic syndrome and hairy cell leukemia. In the present report, a rare case of BPDCN secondary to MF is described. A 70-year-old male patient developed a large purplish-red rash with recurrent symptoms. BPDCN was confirmed by immunohistochemistry of a biopsy specimen and flow cytometry of bone marrow cells. Bone marrow histopathology revealed MF. Next-generation sequencing of peripheral blood revealed mutations in the Tet methylcytosine dioxygenase 2 and NRAS proto-oncogene GTPase genes. The patient underwent one cycle of chemoimmunotherapy, but the condition progressed, an infection developed and the patient eventually died. The present case suggests that BPDCN can occur in conjunction with MF and that the prognosis of such patients is poor. Pathological examination and genetic testing aided in the diagnosis and treatment. This case emphasizes the need to raise awareness of BPDCN among clinicians and to be alert to the potential for fatal infection in patients with BPDCN combined with MF following myelosuppression triggered during chemotherapy.

12.
World J Gastroenterol ; 30(11): 1497-1523, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38617454

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a malignant epithelial tumor, characterized by squamous cell differentiation, it is the sixth leading cause of cancer-related deaths globally. The increased mortality rate of ESCC patients is predominantly due to the advanced stage of the disease when discovered, coupled with higher risk of metastasis, which is an exceedingly malignant characteristic of cancer, frequently leading to a high mortality rate. Unfortunately, there is currently no specific and effective marker to predict and treat metastasis in ESCC. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules, approximately 22 nucleotides in length. miRNAs are vital in modulating gene expression and serve pivotal regulatory roles in the occurrence, progression, and prognosis of cancer. Here, we have examined the literature to highlight the intimate correlations between miRNAs and ESCC metastasis, and show that ESCC metastasis is predominantly regulated or regulated by genetic and epigenetic factors. This review proposes a potential role for miRNAs as diagnostic and therapeutic biomarkers for metastasis in ESCC metastasis, with the ultimate aim of reducing the mortality rate among patients with ESCC.


Assuntos
Carcinoma , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , MicroRNAs , Humanos , MicroRNAs/genética , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/genética , Epigenômica
13.
Neurorehabil Neural Repair ; 38(6): 425-436, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38676561

RESUMO

BACKGROUND: Corticospinal tract (CST) is the principal motor pathway; we aim to explore the structural plasticity mechanism in CST during stroke rehabilitation. METHODS: A total of 25 patients underwent diffusion tensor imaging before rehabilitation (T1), 1-month post-rehabilitation (T2), 2 months post-rehabilitation (T3), and 1-year post-discharge (T4). The CST was segmented, and fractional anisotropy (FA), axial diffusion (AD), mean diffusivity (MD), and radial diffusivity (RD) were determined using automated fiber quantification tractography. Baseline level of laterality index (LI) and motor function for correlation analysis. RESULTS: The FA values of all segments in the ipsilesional CST (IL-CST) were lower compared with normal CST. Repeated measures analysis of variance showed time-related effects on FA, AD, and MD of the IL-CST, and there were similar dynamic trends in these 3 parameters. At T1, FA, AD, and MD values of the mid-upper segments of IL-CST (around the core lesions) were the lowest; at T2 and T3, values for the mid-lower segments were lower than those at T1, while the values for the mid-upper segments gradually increased; at T4, the values for almost entire IL-CST were higher than before. The highest LI was observed at T2, with a predominance in contralesional CST. The LIs for the FA and AD at T1 were positively correlated with the change rate of motor function. CONCLUSIONS: IL-CST showed aggravation followed by improvement from around the lesion to the distal end. Balance of interhemispheric CST may be closely related to motor function, and LIs for FA and AD may have predictive value for mild-to-moderate stroke rehabilitation. Clinical Trial Registration. URL: http://www.chictr.org.cn; Unique Identifier: ChiCTR1800019474.


Assuntos
Imagem de Tensor de Difusão , Plasticidade Neuronal , Tratos Piramidais , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Tratos Piramidais/diagnóstico por imagem , Tratos Piramidais/fisiopatologia , Tratos Piramidais/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Plasticidade Neuronal/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Idoso , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto
14.
Obes Rev ; 25(7): e13748, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38590187

RESUMO

Adipose tissue is the first and primary target organ of obesity and the main source of circulating miRNAs in patients with obesity. This systematic review aimed to analyze and summarize the generation and mechanisms of adipose-derived miRNAs and their role as early predictors of various obesity-related complications. Literature searches in the PubMed and Web of Science databases using terms related to miRNAs, obesity, and adipose tissue. Pre-miRNAs from the Human MicroRNA Disease Database, known to regulate obesity-related metabolic disorders, were combined for intersection processing. Validated miRNA targets were sorted through literature review, and enrichment analysis using the Kyoto Encyclopedia of Genes and Genomes via the KOBAS online tool, disease analysis, and miRNA transcription factor prediction using the TransmiR v. 2.0 database were also performed. Thirty miRNAs were identified using both obesity and adipose secretion as criteria. Seventy-nine functionally validated targets associated with 30 comorbidities of these miRNAs were identified, implicating pathways such as autophagy, p53 pathways, and inflammation. The miRNA precursors were analyzed to predict their transcription factors and explore their biosynthesis mechanisms. Our findings offer potential insights into the epigenetic changes related to adipose-driven obesity-related comorbidities.


Assuntos
Tecido Adiposo , Biomarcadores , Biologia Computacional , MicroRNAs , Obesidade , Humanos , Obesidade/genética , Obesidade/complicações , MicroRNAs/metabolismo , Tecido Adiposo/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo
15.
Front Public Health ; 12: 1320932, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439759

RESUMO

Backgrounds: Observational studies have shown that cigarette smoking is inversely associated with risk of rosacea, However, it remains uncertain whether this association is causal or it is a result of reverse causation, and whether this association is affected by drinking behaviors. Methods: This study utilized the summary-level data from the largest genome-wide association study (GWAS) for smoking, alcohol consumption, and rosacea. The objective was to investigate the effect of genetically predicted exposures to smoking and alcohol consumption on the risk of developing rosacea. Two-sample bidirectional Mendelian randomization (MR) was applied, accompanied by sensitive analyses to validate the robustness of findings. Furthermore, multivariable MR was conducted to evaluate the direct impact of smoking on rosacea. Results: A decreased risk of rosacea was observed in individuals with genetically predicted lifetime smoking [odds ratio (OR)MR - IVW = 0.53; 95% confidence interval (CI), 0.318-0.897; P = 0.017], and number of cigarettes per day (ORMR - IVW = 0.55; 95% CI, 0.358-0.845; P = 0.006). However, no significant associations were found between initiation of regular smoking, smoking cessation, smoking initiation, alcohol consumption and rosacea. Reverse MR analysis did not show any associations between genetic liability toward rosacea and smoking or alcohol drinking. Importantly, the effect of lifetime smoking and the number of cigarettes per day on rosacea remained significant even after adjusting for alcohol consumption in multivariable MR analysis. Conclusion: Smoking was causally related to a lower risk of rosacea, while alcohol consumption does not appear to be associated with risk of rosacea.


Assuntos
Estudo de Associação Genômica Ampla , Rosácea , Humanos , Análise da Randomização Mendeliana , Fumar/efeitos adversos , Fumar/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Rosácea/epidemiologia
16.
Magn Reson Imaging ; 109: 108-119, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38492787

RESUMO

Magnetic resonance imaging (MRI) is non-invasive and crucial for clinical diagnosis, but it has long acquisition time and aliasing artifacts. Accelerated imaging techniques can effectively reduce the scanning time of MRI, thereby decreasing the anxiety and discomfort of patients. Vision Transformer (ViT) based methods have greatly improved MRI image reconstruction, but their computational complexity and memory requirements for the self-attention mechanism grow quadratically with image resolution, which limits their use for high resolution images. In addition, the current generative adversarial networks in MRI reconstruction are difficult to train stably. To address these problems, we propose a Local Vision Transformer (LVT) based adversarial Diffusion model (Diff-GAN) for accelerating MRI reconstruction. We employ a generative adversarial network (GAN) as the reverse diffusion model to enable large diffusion steps. In the forward diffusion module, we use a diffusion process to generate Gaussian mixture distribution noise, which mitigates the gradient vanishing issue in GAN training. This network leverages the LVT module with the local self-attention, which can capture high-quality local features and detailed information. We evaluate our method on four datasets: IXI, MICCAI 2013, MRNet and FastMRI, and demonstrate that Diff-GAN can outperform several state-of-the-art GAN-based methods for MRI reconstruction.


Assuntos
Ansiedade , Artefatos , Humanos , Difusão , Fontes de Energia Elétrica , Imageamento por Ressonância Magnética , Processamento de Imagem Assistida por Computador
17.
Sci Total Environ ; 926: 171712, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38494024

RESUMO

Understanding the factors driving propagation from meteorological to hydrological drought is crucial for drought mitigation. In this study, an integrated framework based on the Soil and Water Assessment Tool model, standardised drought indices and Geographical Detector were used to investigate how and to what extent watershed properties and human activities affect the spatial heterogeneity of drought propagation in the Wei River Basin, a typical arid and semi-arid region in China. Results indicated that (1) spatially, the propagation times increased from southwest to northeast. Seasonally, the propagation was shorter and stronger in summer and autumn. (2) The aridity index significantly affected the spatial distribution of drought propagation time for the entire basin, especially in summer, while human activities primarily drove spatial distribution in the sub-basins. The explanatory power of any two independent factors was non-linearly enhanced after the interaction. (3) Watershed properties potentially impacted the anthropogenic driving factor of drought propagation. Strong anthropogenic effects on drought propagation often occurred in watersheds with moderate drought levels, steep slopes, low elevations, and small areas, and the key factors varied seasonally. These findings help elucidate the multifaceted effects of watershed properties and human activities on drought propagation. The proposed framework and the results of this study provide valuable guidance for formulating precise drought control strategies in the Wei River Basin and worldwide.

18.
ACS Nano ; 18(6): 4783-4795, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38301134

RESUMO

Contrast-enhanced magnetic resonance imaging (CE-MRI) of acute kidney injury (AKI) is severely hindered by the poor targeting capacity and potential toxicity of current contrast agents. Herein, we propose one-step fabrication of a bovine serum albumin@polydopamine@Fe (BSA@PDA@Fe, BPFe) nanoprobe with self-purification capacity for targeted CE-MRI of AKI. BSA endows the BPFe nanoprobe with renal tubule-targeting ability, and PDA is capable of completely inhibiting the intrinsic metal-induced reactive oxygen species (ROS), which are always involved in Fe/Mn-based agents. The as-prepared nanoprobe owns a tiny size of 2.7 nm, excellent solubility, good T1 MRI ability, superior biocompatibility, and powerful antioxidant capacity. In vivo CE-MRI shows that the BPFe nanoprobe can accumulate in the renal cortex due to the reabsorption effect toward the serum albumin. In the AKI model, impaired renal reabsorption function can be effortlessly detected via the diminishment of renal cortical signal enhancement. More importantly, the administration of the BPFe nanoprobe would not aggravate renal damage of AKI due to the outstanding self-purification capacity. Besides, the BPFe nanoprobe is employed for CE-MR angiography to visualize fine vessel structures. This work provides an MRI contrast agent with good biosafety and targeting ability for CE-MRI of kidney diseases.


Assuntos
Injúria Renal Aguda , Indóis , Polímeros , Humanos , Meios de Contraste/química , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
19.
Biomaterials ; 306: 122498, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38310828

RESUMO

Magnetic hyperthermia therapy (MHT) has garnered immense interest due to its exceptional spatiotemporal specificity, minimal invasiveness and remarkable tissue penetration depth. Nevertheless, the limited magnetothermal heating capability and the potential toxicity of metal ions in magnetic materials based on metallic elements significantly impede the advancement of MHT. Herein, we introduce the concept of nonmetallic materials, with graphite (Gra) as a proof of concept, as a highly efficient and biocompatible option for MHT of tumors in vivo for the first time. The Gra exhibits outstanding magnetothermal heating efficacy owing to the robust eddy thermal effect driven by its excellent electrical conductivity. Furthermore, being composed of carbon, Gra offers superior biocompatibility as carbon is an essential element for all living organisms. Additionally, the Gra boasts customizable shapes and sizes, low cost, and large-scale production capability, facilitating reproducible and straightforward manufacturing of various Gra implants. In a mouse tumor model, Gra-based MHT successfully eliminates the tumors at an extremely low magnetic field intensity, which is less than one-third of the established biosafety threshold. This study paves the way for the development of high-performance magnetocaloric materials by utilizing nonmetallic materials in place of metallic ones burdened with inherent limitations.


Assuntos
Grafite , Hipertermia Induzida , Neoplasias , Animais , Camundongos , Neoplasias/terapia , Campos Magnéticos
20.
J Control Release ; 367: 197-208, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246205

RESUMO

Melanoma, one of the most devastating forms of skin cancer, currently lacks effective clinical treatments. Delivery of functional genes to modulate specific protein expression to induce melanoma cell apoptosis could be a promising therapeutic approach. However, transfecting melanoma cells using non-viral methods, particularly with cationic polymers, presents significant challenges. In this study, we synthesized three branched poly(ß-amino ester)s (HPAEs) with evenly distributed branching units but varying space lengths through a two-step "oligomer combination" strategy. The unique topological structure enables HPAEs to condense DNA to form nano-sized polyplexes with favorable physiochemical properties. Notably, HPAEs, especially HPAE-2 with intermediate branching unit space length, demonstrated significantly higher gene transfection efficiency than the leading commercial gene transfection reagent, jetPRIME, in human melanoma cells. Furthermore, HPAE-2 efficiently delivered the Bax-encoding plasmid into melanoma cells, leading to a pronounced pro-apoptotic effect without causing noticeable cytotoxicity. This study establishes a potent non-viral platform for gene transfection of melanoma cells by harnessing the distribution of branching units, paving the way for potential clinical applications of gene therapy in melanoma treatment.


Assuntos
Ésteres , Melanoma , Polímeros , Humanos , Transfecção , Ésteres/química , Melanoma/genética , Melanoma/terapia , Apoptose , Técnicas de Transferência de Genes
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