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1.
J Mater Chem B ; 12(13): 3171-3190, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38488129

RESUMO

Electrospun nanofiber membranes hold great promise as scaffolds for tissue reconstruction, mirroring the natural extracellular matrix (ECM) in their structure. However, their limited bioactive functions have hindered their effectiveness in fostering wound healing. Inorganic nanoparticles possess commendable biocompatibility, which can expedite wound healing; nevertheless, deploying them in the particle form presents challenges associated with removal or collection. To capitalize on the strengths of both components, electrospun organic/inorganic hybrid nanofibers (HNFs) have emerged as a groundbreaking solution for accelerating wound healing and maintaining stability throughout the healing process. In this review, we provide an overview of recent advancements in the utilization of HNFs for wound treatment. The review begins by elucidating various fabrication methods for hybrid nanofibers, encompassing direct electrospinning, coaxial electrospinning, and electrospinning with subsequent loading. These techniques facilitate the construction of micro-nano structures and the controlled release of inorganic ions. Subsequently, we delve into the manifold applications of HNFs in promoting the wound regeneration process. These applications encompass hemostasis, antibacterial properties, anti-inflammatory effects, stimulation of cell proliferation, and facilitation of angiogenesis. Finally, we offer insights into the prospective trends in the utilization of hybrid nanofiber-based wound dressings, charting the path forward in this dynamic field of research.


Assuntos
Nanofibras , Nanofibras/química , Estudos Prospectivos , Cicatrização , Antibacterianos/farmacologia , Bandagens
2.
Macromol Biosci ; : e2300399, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38011585

RESUMO

Sustainable and controllable drug transport is one of the most efficient ways of disease treatment. Due to high biocompatibility, good biodegradability, and low costs, chitosan and its derivatives are widely used in biomedical fields. Specifically, chitosan hydrogel enables drugs to pass through biological barriers because of their abundant amino and hydroxyl groups that can interact with human tissues. Moreover, the multi-responsive nature (pH, temperature, ions strength, and magnetic field, etc.) of chitosan hydrogels makes precise drug release a possibility. Here, the synthesis methods, modification strategies, stimuli-responsive mechanisms of chitosan-based hydrogels, and their recent progress in drug delivery are summarized. Chitosan hydrogels that carry and release drugs through subcutaneous (dealing with wound dressing), oral (dealing with gastrointestinal tract), and facial (dealing with ophthalmic, ear, and brain) are reviewed. Finally, challenges toward clinic application and the future prospects of stimuli-responsive chitosan-based hydrogels are indicated.

3.
Natl Sci Rev ; 10(9): nwad137, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37565186

RESUMO

Decades of research using remotely sensed data have extracted evidence for the presence of an ocean in the northern lowlands of Mars in the Hesperian (∼3.3 Ga), but these claims have remained controversial due to the lack of in situ analysis of the associated geologic unit, the Vastitas Borealis Formation (VBF). The Tianwen-1/Zhurong rover was targeted to land within the VBF near its southern margin and has traversed almost 2 km southward toward the interpreted shoreline. We report here on the first in situ analysis of the VBF that reveals sedimentary structures and features in surface rocks that suggest that the VBF was deposited in a marine environment, providing direct support for the existence of an ancient (Hesperian) ocean on Mars.

4.
Cereb Cortex ; 33(9): 5082-5096, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36288912

RESUMO

Advances in Magnetic Resonance Imaging hardware and methodologies allow for promoting the cortical morphometry with submillimeter spatial resolution. In this paper, we generated 3D self-enhanced high-resolution (HR) MRI imaging, by adapting 1 deep learning architecture, and 3 standard pipelines, FreeSurfer, MaCRUISE, and BrainSuite, have been collectively employed to evaluate the cortical thickness. We systematically investigated the differences in cortical thickness estimation for MRI sequences at multiresolution homologously originated from the native image. It has been revealed that there systematically exhibited the preferences in determining both inner and outer cortical surfaces at higher resolution, yielding most deeper cortical surface placements toward GM/WM or GM/CSF boundaries, which directs a consistent reduction tendency of mean cortical thickness estimation; on the contrary, the lower resolution data will most probably provide a more coarse and rough evaluation in cortical surface reconstruction, resulting in a relatively thicker estimation. Although the differences of cortical thickness estimation at the diverse spatial resolution varied with one another, almost all led to roughly one-sixth to one-fifth significant reduction across the entire brain at the HR, independent to the pipelines we applied, which emphasizes on generally coherent improved accuracy in a data-independent manner and endeavors to cost-efficiency with quantitative opportunities.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Córtex Cerebral
5.
Sci Adv ; 8(39): eabq2542, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36170359

RESUMO

Impact glasses found in lunar soils provide a possible window into the impact history of the inner solar system. However, their use for precise reconstruction of this history is limited by an incomplete understanding of the physical mechanisms responsible for their origin and distribution and possible relationships to local and regional geology. Here, we report U-Pb isotopic dates and chemical compositions of impact glasses from the Chang'e-5 soil and quantitative models of impact melt formation and ejection that account for the compositions of these glasses. The predominantly local provenance indicated by their compositions, which constrains transport distances to <~150 kilometers, and the age-frequency distribution are consistent with formation mainly in impact craters 1 to 5 kilometers in diameter. Based on geological mapping and impact cratering theory, we tentatively identify specific craters on the basaltic unit sampled by Chang'e-5 that may have produced these glasses and compare their ages with the impact record of the asteroid belt.

6.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281206

RESUMO

The basic helix-loop-helix (bHLH) transcription factor family is one of the largest transcription factor gene families in Arabidopsis thaliana, and contains a bHLH motif that is highly conserved throughout eukaryotic organisms. Members of this family have two conserved motifs, a basic DNA binding region and a helix-loop-helix (HLH) region. These proteins containing bHLH domain usually act as homo- or heterodimers to regulate the expression of their target genes, which are involved in many physiological processes and have a broad range of functions in biosynthesis, metabolism and transduction of plant hormones. Although there are a number of articles on different aspects to provide detailed information on this family in plants, an overall summary is not available. In this review, we summarize various aspects of related studies that provide an overview of insights into the pleiotropic regulatory roles of these transcription factors in plant growth and development, stress response, biochemical functions and the web of signaling networks. We then provide an overview of the functional profile of the bHLH family and the regulatory mechanisms of other proteins.


Assuntos
Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sequência de Aminoácidos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Expressão Gênica , Genoma de Planta , Sequências Hélice-Alça-Hélice , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Análise de Sequência de DNA/métodos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Iran J Public Health ; 50(11): 2246-2253, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35223599

RESUMO

BACKGROUND: We aimed to explore and analyze the relationships between mean corpuscular volume (MCV), red blood cell distribution width (RDW) and hypotension in patients with hemodialysis. METHODS: The clinical data of 163 patients from the Xinghua People's Hospital, Taizhou, China with hemodialysis were retrospectively analyzed. The incidence of hypotension was counted and the levels of MCV and RDW were compared between the patients with and without hemodialysis. MCV and RDW were analyzed as possible influencing factors of hypotension. Receiver operating characteristic curve (ROC) was drawn to analyze the effect of MCV and RDW on the risk assessment of hypotension in patients with hemodialysis. RESULTS: MCV in patients with hypotension was significantly lower than those without hypotension (P < 0.05), and RDW was higher than those without hypotension (P < 0.05). The constituent ratio of higher age (>60), diabetic nephropathy, maintenance hemodialysis, MCV < 80fl, RDW > 14.8%, malnutrition, anemia, ultra-filtration rate, diet during dialysis, coronary heart disease, atrial fibrillation and antihypertensive drugs before dialysis were higher in patients with hypotension than those without hypotension (P < 0.05). The sensitivity, specificity and AUC of the combination of MCV and RDW were higher than those of the single assessment. MCV is lower in patients with hypotension and RDW is higher than those in patients without hypotension. CONCLUSION: MCV combined with RDW has a good evaluation effect.

8.
PLoS One ; 11(4): e0153415, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27070782

RESUMO

The response of microbial respiration from soil organic carbon (SOC) decomposition to environmental changes plays a key role in predicting future trends of atmospheric CO2 concentration. However, it remains uncertain whether there is a universal trend in the response of microbial respiration to increased temperature and nutrient addition among different vegetation types. In this study, soils were sampled in spring, summer, autumn and winter from five dominant vegetation types, including pine, larch and birch forest, shrubland, and grassland, in the Saihanba area of northern China. Soil samples from each season were incubated at 1, 10, and 20°C for 5 to 7 days. Nitrogen (N; 0.035 mM as NH4NO3) and phosphorus (P; 0.03 mM as P2O5) were added to soil samples, and the responses of soil microbial respiration to increased temperature and nutrient addition were determined. We found a universal trend that soil microbial respiration increased with increased temperature regardless of sampling season or vegetation type. The temperature sensitivity (indicated by Q10, the increase in respiration rate with a 10°C increase in temperature) of microbial respiration was higher in spring and autumn than in summer and winter, irrespective of vegetation type. The Q10 was significantly positively correlated with microbial biomass and the fungal: bacterial ratio. Microbial respiration (or Q10) did not significantly respond to N or P addition. Our results suggest that short-term nutrient input might not change the SOC decomposition rate or its temperature sensitivity, whereas increased temperature might significantly enhance SOC decomposition in spring and autumn, compared with winter and summer.


Assuntos
Carbono/química , Solo/química , Bactérias/metabolismo , Betula/microbiologia , Biomassa , China , Ecossistema , Florestas , Fungos/metabolismo , Pradaria , Larix/microbiologia , Nitrogênio/química , Pinus/microbiologia , Estações do Ano , Microbiologia do Solo , Temperatura
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