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1.
Small ; : e2403800, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39163609

RESUMO

Self-propelled nanomotors possess strong propulsion and penetration abilities, which can increase the efficiency of cellular uptake of nanoparticles and enhance their cytotoxicity against tumor cells, opening a new path for treating major diseases. In this study, the concept of driving nanomotors by alternately stretching and contracting a temperature-sensitive polymer (TS-P) chain is proposed. The TS-Ps are successfully linked to one side of Cu2-xSe@Au (CS@Au) nanoparticles to form a Janus structure, which is designated as Cu2-xSe@Au-polymer (CS@Au-P) nanomotors. Under near-infrared (NIR) light irradiation, Cu2-xSe nanoparticles generate photothermal effects that change the system temperature, triggering the alternation of the TS-P structure to generate a mechanical force that propels the motion of CS@Au-P nanomotors. The nanomotor significantly improved the cellular uptake of nanoparticles and enhanced their penetration and accumulation in tumor. Furthermore, the exceptional photothermal conversion efficiency of CS@Au-P nanomotors suggests their potential as nanomaterials for photothermal therapy (PTT). The prepared material exhibited good biocompatibility and anti-tumor effects both in vivo and in vitro, providing new research insights into the design and application of nanomotors in tumor therapy.

2.
Am J Cancer Res ; 14(7): 3294-3316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113874

RESUMO

Calcium ions (Ca2+) are crucial in tumorigenesis and progression, with their elevated levels indicating a negative prognosis in Kidney Renal Clear Cell Carcinoma (KIRC). The influence of genes regulating calcium ions on the survival outcomes of KIRC patients and their interaction with the tumor's immune microenvironment is yet to be fully understood. This study analyzed gene expression data from KIRC tumor and adjacent non-tumor tissues using the TCGA-KIRC dataset to pinpoint genes that are differentially expressed in KIRC. Intersection of these genes with those regulating calcium ions highlighted specific calcium ion-regulating genes that exhibit differential expression in KIRC. Subsequently, prognostic risk models were developed using univariate Cox and LASSO-Cox regression analyses to verify their diagnostic precision. Additionally, the study investigated the correlation between tumor immunity and KIRC patient outcomes, assessing the contribution of STAC3 genes to tumor immunity. Further exploration entailed SSGASE, single-cell analysis, pseudotime analysis and both in vivo and in vitro experiments to evaluate STAC3's role in tumor immunity and progression. Notably, STAC3 was significantly overexpressed in tumor specimens and positively correlated with the degree of malignancy of KIRC, affecting patients' prognosis. Elevated STAC3 expression correlated with enhanced immune infiltration in KIRC tumors. Furthermore, silencing STAC3 curtailed KIRC cell proliferation, migration, invasion, and stemness properties. Experimental models in mice confirmed that STAC3 knockdown led to a reduction in tumor growth. Elevated STAC3 expression is intricately linked with immune infiltration in KIRC tumors, as well as with the aggressive biological behaviors of tumor cells, including their proliferation, migration, and invasion. Targeting STAC3 presents a promising strategy to augment the efficacy of current therapeutic approaches and to better the survival outcomes of patients with KIRC.

3.
Front Neurol ; 15: 1370029, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38872827

RESUMO

Introduction: Research indicates that individuals experiencing hemorrhagic stroke face a greater likelihood of developing lower extremity deep vein thrombosis (DVT) compared to those with ischemic stroke. This study aimed to assess the predictive capacity of the Caprini risk assessment model (RAM), D-dimer (D-D) levels, and fibrinogen (FIB) levels for lower extremity DVT in patients with spontaneous intracerebral hemorrhage (sICH). Methodology: This study involved a retrospective analysis of medical records from all sICH patients admitted to Shanghai General Hospital between June 2020 and June 2023. Within 48 h of admission, patients underwent routine screening via color Doppler ultrasonography (CDUS). Patients were categorized into the DVT and control groups based on the occurrence of lower extremity DVT during hospitalization. Differences in Caprini RAM, D-dimer, and FIB levels between the two groups were compared. The sensitivity and specificity of combined Caprini RAM, peripheral blood D-dimer, and FIB levels in predicting lower extremity DVT in sICH patients were analyzed. Receiver operating characteristic (ROC) curves assessed the overall predictive accuracy of Caprini RAM, D-D, and FIB levels. Results: The study involving 842 sICH patients revealed 225 patients with DVT and 617 patients without DVT. Caprini RAM, D-D, and FIB levels were significantly higher in the DVT group compared to the control group (P < 0.05). Sensitivity values for Caprini RAM, D-D, and FIB levels in predicting lower extremity DVT in sICH patients were 0.920, 0.893, and 0.680, respectively, while specificities were 0.840, 0.680, and 0.747, respectively. The ROC curve analysis demonstrated an area under the curve (AUC) of 0.947 for combined DVT prediction, with 97.33% sensitivity and 92.00% specificity, indicating superior predictive value compared to individual applications of Caprini RAM, D-D, and FIB levels. Conclusion: The combined utilization of Caprini RAM, D-D, and FIB levels holds significant clinical relevance in predicting lower extremity DVT in sICH patients.

4.
Org Lett ; 26(24): 5063-5068, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38864356

RESUMO

Here, we disclosed an unprecedented cobalt electrocatalyzed atroposelective C-H activation and annulation for the efficient construction of diversely functionalized N-N axes in an undivided cell. A broad range of allene substrates and benzamides bearing different functionalities are compatible with generating axially chiral products with good yields and excellent enantioselectivities (up to 92% yield and 99% ee). A series of synthetic applications and control experiments were also performed, which further expanded the practicality of this strategy.

5.
Adv Clin Exp Med ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819938

RESUMO

BACKGROUND: Liqi Tongbian is a traditional Chinese medicine (TCM) preparation that contains herbs that may treat slow transit constipation (STC). Atractylodes macrocephala, Astragalus membranaceus, Fructus aurantii, radish seed, uncooked Polygonum multiflorum, and Agastache rugosa were included in the formula for their unique qualities. The control of water transfer in the colon is greatly influenced by aquaporin 3 (AQP3). OBJECTIVES: Based on this, the Liqi Tongbian mixture was used to detect the concentrations of aquaporins (AQPs), 5-HT and nitrix oxide synthase 1 (NOS1) in STC rats, and explore its effect, in order to provide a theoretical basis for the remedy of STC with TCM. MATERIAL AND METHODS: Zhejiang University of Traditional Chinese Medicine provided 32 three-week-old Sprague Dawley rats of SPF-grade. The pairs licensed under SYXK (Zhejiang) 2021-0012 were kept at 20-25°C and humidity of 50-65%. The compound diphenoxylate caused constipation in the control, model, Liqi laxative (LQTB), and mosapride groups. The Liqi laxative rats were administered a mixture of traditional Chinese herbs after modeling, while mosapride was given to the other group. The levels of 5-HT, NOS1 and AQPs were tested in the feces and intestinal tissues. RESULTS: Comparing the condition of rat feces, it was found that the model group had significantly lower overall bulk, score and particles within 24 h compared to the control group. In comparison to mosapride, LQTB performed better. The model group had higher levels of 5-HT and NOS1 in intestinal tissue, while the LQTB and mosapride groups had decreased levels of these AQPs. LQTB had lower levels of AQP1, AQP3 and AQP4 than mosapride, while the model group had higher levels of these AQPs. CONCLUSIONS: Liqi Tongbian mixture works better than mosapride in improving constipation symptoms in rats with STC, and its mechanism is related to regulating the level of intestinal AQPs and neurotransmitters.

6.
Front Immunol ; 15: 1376962, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562940

RESUMO

Tumors pose a significant global public health challenge, resulting in numerous fatalities annually. CD8+ T cells play a crucial role in combating tumors; however, their effectiveness is compromised by the tumor itself and the tumor microenvironment (TME), resulting in reduced efficacy of immunotherapy. In this dynamic interplay, extracellular vesicles (EVs) have emerged as pivotal mediators, facilitating direct and indirect communication between tumors and CD8+ T cells. In this article, we provide an overview of how tumor-derived EVs directly regulate CD8+ T cell function by carrying bioactive molecules they carry internally and on their surface. Simultaneously, these EVs modulate the TME, indirectly influencing the efficiency of CD8+ T cell responses. Furthermore, EVs derived from CD8+ T cells exhibit a dual role: they promote tumor immune evasion while also enhancing antitumor activity. Finally, we briefly discuss current prevailing approaches that utilize functionalized EVs based on tumor-targeted therapy and tumor immunotherapy. These approaches aim to present novel perspectives for EV-based tumor treatment strategies, demonstrating potential for advancements in the field.


Assuntos
Vesículas Extracelulares , Neoplasias , Humanos , Linfócitos T CD8-Positivos , Vesículas Extracelulares/metabolismo , Neoplasias/metabolismo , Linfócitos T Citotóxicos , Microambiente Tumoral
7.
ACS Appl Mater Interfaces ; 16(17): 22361-22368, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38628106

RESUMO

Spin-coated quasi-two-dimensional halide perovskite films, which exhibit superior optoelectronic properties and environmental stability, have recently been extensively studied for lasers. Crystallinity is of great importance for the laser performance. Although some parameters related to the spin-coating process have been studied, the in-depth understanding and effective control of the acceleration rate on two-dimensional perovskite crystallization during spin-coating are still unknown. Here we investigate the effect of solvent evaporation on the microstructure of the final perovskite films during the spin-coating process. The crystallization quality of the film can be significantly improved by controlling solvent evaporation. As a result, the prepared quasi-2D perovskite film exhibits a stimulated emission threshold (pump: 343 nm, 6 kHz, 290 fs) of 550 nm as low as 16.2 µJ/cm2. Transient absorption characterization shows that the radiative biexciton recombination time is reduced from 738.5 to 438.3 ps, benefiting from the improved crystallinity. The faster biexciton recombination significantly enhanced the photoluminescence efficiency, which is critical for population inversion. This work could contribute to the development of low-threshold lasers.

8.
Opt Express ; 32(4): 6258-6265, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439333

RESUMO

Quasi-two-dimensional perovskites have attracted widespread interest in developing low-cost high-quality small lasers. The nano cavity based on topologically protected valley edge states can be robust against special defects. Here, we report a high-quality two-dimensional perovskite topological photonic crystal laser based on the quantum valley Hall effect. By adjusting the position of the air holes relative to the pillar, radiation leakage in topological edge states is reduced to a large extent, electric field distribution becomes more uniform and the quality factor can be as high as 3.6 × 104. Our findings could provide opportunities for the development of high-power, stable perovskite lasers with topological protection.

9.
Int J Med Inform ; 185: 105353, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38442665

RESUMO

BACKGROUND: Global mental health issues have increased the demand for digital mental health support. Mobile apps with persuasive technology play a vital role in enhancing mental well-being. OBJECTIVE: Analysing and Comparing persuasive intervention design across various app categories, this study aims to inspire innovative design approaches for improving the persuasiveness of mental wellness apps during their development. METHODS: We retrieved a total of 100 mobile apps from five distinct categories (20 for each): Mental wellness, Social media, Entertainment, Fitness & Physical health and News & Information from Apple Store and Google Play. Two researchers examined and coded the apps to identify the persuasive features employed within each category using the Persuasive Systems Design (PSD) Framework, while a third researcher participated in discussions to resolve discrepancies. Kendall's Rank Correlation Coefficient was performed to determine the relationship between persuasive features and effectiveness. RESULTS: Trustworthiness (n = 81), Liking (n = 78), Surface credibility (n = 71), Reminders (n = 63), and Reduction (n = 57) were the most widely implemented persuasive features. Dialogue support and system credibility support features were heavily used across different app types, while social support features were less commonly employed, particularly in mental health apps. A positive correlation was found between Surface credibility, Trustworthiness, Liking, Reminders, Self-monitoring, Expertise features and apps' effectiveness. CONCLUSION: Through a cross-domain analysis using the PSD framework to investigate persuasive feature implementations, the findings from this study offer design suggestions to create innovative and effective mobile apps promoting mental well-being.


Assuntos
Saúde Mental , Aplicativos Móveis , Humanos , Exercício Físico
10.
Angew Chem Int Ed Engl ; 63(17): e202402231, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38407456

RESUMO

The development of new methods for regio- and stereoselective activation of C-O bonds in ethers holds significant promise for synthetic chemistry, offering advantages in terms of environmental sustainability and economic efficiency. Moreover, the C-N atropisomers represent a fascinating and crucial chiral system, extensively found in natural products, pharmaceutical leads, and the frameworks of advanced materials. In this work, we have introduced a nickel-catalyzed regio- and enantioselective carbon-oxygen arylation reaction for atroposelective synthesis of N-arylisoquinoline-1,3(2H,4H)-diones. The high regioselectivity of C-O cleavage benefits from the high stability of the in situ formed (amido)ethenolate via oxidative addition. Additionally, the self-activation of the aryl C-O bond facilitates the reaction under mild conditions, leading to outstanding enantioselectivities. The diverse post-functionalizations of the axially chiral isoquinoline-1,3(2H,4H)-diones further highlighted the utility of this protocol in preparing valuable C-N atropisomers, including the chiral phosphine ligands.

11.
Angew Chem Int Ed Engl ; 63(20): e202403667, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38407803

RESUMO

Natural redox-regulated channel proteins often utilize disulfide bonds as redox sensors for adaptive regulation of channel conformations in response to diverse physiological environments. In this study, we developed novel synthetic ion channels capable of reversibly switching their ion-transport capabilities by incorporating multiple disulfide bonds into artificial systems. X-ray structural analysis and electrophysiological experiments demonstrated that these disulfide-bridged molecules possess well-defined tubular cavities and can be efficiently inserted into lipid bilayers to form artificial ion channels. More importantly, the disulfide bonds in these molecules serve as redox-tunable switches to regulate the formation and disruption of ion-permeation pathways, thereby achieving a transition in the transmembrane transport process between the ON and OFF states.


Assuntos
Dissulfetos , Canais Iônicos , Transporte de Íons , Oxirredução , Dissulfetos/química , Canais Iônicos/metabolismo , Canais Iônicos/química , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Modelos Moleculares , Cristalografia por Raios X
12.
IEEE Trans Biomed Eng ; 71(6): 1879-1888, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38231824

RESUMO

To improve the signal collection efficiency of Optical Coherence Tomography (OCT) for biomedical applications. A novel coaxial optical design was implemented, utilizing a wavefront-division beam splitter in the sample arm with a 45-degree rod mirror. This design allowed for the simultaneous collection of bright and dark field signals. The bright field signal was detected within its circular aperture in a manner similar to standard OCT, while the dark field signal passed through an annular-shaped aperture and was collected by the same spectrometer via a fiber array. This new configuration improved the signal collection efficiency by ∼3 dB for typical biological tissues. Dark-field OCT images were found to provide higher resolution, contrast and distinct information compared to standard bright-field OCT. By compounding bright and dark field images, speckle noise was suppressed by ∼ √2 . These advantages were validated using Teflon phantoms, chicken breast ex vivo, and human skin in vivo. This new OCT configuration significantly enhances signal collection efficiency and image quality, offering great potential for improving OCT technology with better depth, contrast, resolution, speckles, and signal-to-noise ratio. We believe that the bright and dark field signals will enable more comprehensive tissue characterization with the angled scattered light. This advancement will greatly promote the OCT technology in various clinical and biomedical research applications.


Assuntos
Galinhas , Desenho de Equipamento , Imagens de Fantasmas , Tomografia de Coerência Óptica , Tomografia de Coerência Óptica/métodos , Tomografia de Coerência Óptica/instrumentação , Animais , Humanos , Pele/diagnóstico por imagem , Razão Sinal-Ruído , Processamento de Sinais Assistido por Computador , Processamento de Imagem Assistida por Computador/métodos
13.
Int J Mol Sci ; 24(24)2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38139371

RESUMO

Forming pyridine salts to construct covalent organic cages is an effective strategy for constructing covalent cage compounds. Covalent organic cages based on pyridine salt structures are prone to form water-soluble supramolecular compounds. Herein, we designed and synthesized a triangular prism-shaped hexagonal cage with a larger cavity and relatively flexible conformation. The supramolecular cage structure was also applied to the encapsulation of pyrene and information encryption.


Assuntos
Pirenos , Piridinas , Cloreto de Sódio , Água
14.
Front Oncol ; 13: 1263685, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38264739

RESUMO

Background: Breast cancer is the key global menace to women's health, which ranks first by mortality rate. The rate reduction and early diagnostics of breast cancer are the mainstream of medical research. Immunohistochemical examination is the most important link in the process of breast cancer treatment, and its results directly affect physicians' decision-making on follow-up medical treatment. Purpose: This study aims to develop a computer-aided diagnosis (CAD) method based on deep learning to classify breast ultrasound (BUS) images according to immunohistochemical results. Methods: A new depth learning framework guided by BUS image data analysis was proposed for the classification of breast cancer nodes in BUS images. The proposed CAD classification network mainly comprised three innovation points. First, a multilevel feature distillation network (MFD-Net) based on CNN, which could extract feature layers of different scales, was designed. Then, the image features extracted at different depths were fused to achieve multilevel feature distillation using depth separable convolution and reverse depth separable convolution to increase convolution depths. Finally, a new attention module containing two independent submodules, the channel attention module (CAM) and the spatial attention module (SAM), was introduced to improve the model classification ability in channel and space. Results: A total of 500 axial BUS images were retrieved from 294 patients who underwent BUS examination, and these images were detected and cropped, resulting in breast cancer node BUS image datasets, which were classified according to immunohistochemical findings, and the datasets were randomly subdivided into a training set (70%) and a test set (30%) in the classification process, with the results of the four immune indices output simultaneously from training and testing, in the model comparison experiment. Taking ER immune indicators as an example, the proposed model achieved a precision of 0.8933, a recall of 0.7563, an F1 score of 0.8191, and an accuracy of 0.8386, significantly outperforming the other models. The results of the designed ablation experiment also showed that the proposed multistage characteristic distillation structure and attention module were key in improving the accuracy rate. Conclusion: The extensive experiments verify the high efficiency of the proposed method. It is considered the first classification of breast cancer by immunohistochemical results in breast cancer image processing, and it provides an effective aid for postoperative breast cancer treatment, greatly reduces the difficulty of diagnosis for doctors, and improves work efficiency.

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