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1.
Nat Commun ; 15(1): 2031, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448415

RESUMO

Multimode fibers (MMFs) are gaining renewed interest for nonlinear effects due to their high-dimensional spatiotemporal nonlinear dynamics and scalability for high power. High-brightness MMF sources with effective control of the nonlinear processes would offer possibilities in many areas from high-power fiber lasers, to bioimaging and chemical sensing, and to intriguing physics phenomena. Here we present a simple yet effective way of controlling nonlinear effects at high peak power levels. This is achieved by leveraging not only the spatial but also the temporal degrees of freedom during multimodal nonlinear pulse propagation in step-index MMFs, using a programmable fiber shaper that introduces time-dependent disorders. We achieve high tunability in MMF output fields, resulting in a broadband high-peak-power source. Its potential as a nonlinear imaging source is further demonstrated through widely tunable two-photon and three-photon microscopy. These demonstrations provide possibilities for technology advances in nonlinear optics, bioimaging, spectroscopy, optical computing, and material processing.

2.
Chem Commun (Camb) ; 60(17): 2397-2400, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38323363

RESUMO

Herein, we report the synthesis of a two-dimensional metal-organic framework (MOF), assembled from octahedral metal-organic cages featuring phenanthroline-based carboxylate linkers and µ3-oxo-centered trinuclear Sc(III) inorganic building blocks. We study the performance of this MOF towards the capture of sulfur hexafluoride (SF6). On account of its structural features and porous nature, this MOF displays an SF6 uptake capacity of 0.92 mmol g-1 at 0.1 bar and an isosteric heat of adsorption of about 30.7 kJ mol-1 for SF6, illustrating its potential application for the selective capture of SF6 from N2. In addition, we study the adsorptive binding mechanism of SF6 and N2 inside this MOF via molecular simulations.

3.
Front Optoelectron ; 15(1): 50, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36567731

RESUMO

Nanofibers have a wide range of applications in many fields such as energy generation and storage, environmental sensing and treatment, biomedical and health, thanks to their large specific surface area, excellent flexibility, and superior mechanical properties. With the expansion of application fields and the upgrade of application requirements, there is an inevitable trend of improving the performance and functions of nanofibers. Over the past few decades, numerous studies have demonstrated how nanofibers can be adapted to more complex needs through modifications of their structures, materials, and assembly. Thus, it is necessary to systematically review the field of nanofibers in which new ideas and technologies are emerging. Here we summarize the recent advanced strategies to improve the performances and expand the functions of nanofibers. We first introduce the common methods of preparing nanofibers, then summarize the advances in the field of nanofibers, especially up-to-date strategies for further enhancing their functionalities. We classify these strategies into three categories: design of nanofiber structures, tuning of nanofiber materials, and improvement of nanofibers assemblies. Finally, the optimization methods, materials, application areas, and fabrication methods are summarized, and existing challenges and future research directions are discussed. We hope this review can provide useful guidance for subsequent related work.

4.
Quant Imaging Med Surg ; 12(1): 425-438, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34993091

RESUMO

BACKGROUND: The challenges of clinical translation of optical imaging, including the limited availability of clinically used imaging probes and the restricted penetration depth of light propagation in tissues can be avoided using Cerenkov luminescence endoscopy (CLE). However, the clinical applications of CLE are limited due to the low signal level of Cerenkov luminescence and the large transmission loss caused by the endoscope, which results in a relatively low detection sensitivity of current CLE. The aim of this study was to enhance the detection sensitivity of the CLE system and thus improve the system for clinical application in the detection of gastrointestinal diseases. METHODS: Four optical fiber endoscopes were customized with different system parameters, including monofilament (MF) diameter of imaging fiber bundles, fiber material, probe coating, etc. The endoscopes were connected to the detector via a specifically designed straight connection device to form the CLE system. The ß-2-[18F]-Fluoro-2-deoxy-D-glucose (18F-FDG) solution and the radionuclide of Gallium-68 (68Ga) were used to evaluate the performance of the CLE system. The images of the 18F-FDG solution acquired by the CLE were used to optimize imaging parameters of the system. By using the endoscope with optimized parameters, including the MF diameter of imaging fiber bundles, fiber materials, etc., the resolution and sensitivity of the assembled CLE system were measured by imaging the radionuclide of 68Ga. RESULTS: The results of 18F-FDG experiments showed that larger MF diameter led to higher collection efficiency. The fiber material and probe coating with high transmission ratios in the range of 400-900 nm also increased signal collection and transmission efficiency. The results of 68Ga evaluations showed that a minimum radioactive activity of radionuclides as low as 0.03 µCi was detected in vitro within 5 minutes, while that of 0.68 µCi can be detected within 1 minute. In vivo experiments also demonstrated that the developed CLE system achieved a high sensitivity at a submicrocurie level; that is, 0.44 µCi within 5 minutes, and 0.83 µCi within 1 minute. The weaker in vivo sensitivity was due to the attenuation of the signal by the mouse tissue skin and the autofluorescence interference produced by biological tissues. CONCLUSIONS: By optimizing the structural parameters of fiber endoscope and imaging parameters for data acquisition, we developed a CLE system with a sensitivity at submicrocurie level. These results support the possibility that this technology can clinically detect early tumors within 1 minute.

5.
Front Optoelectron ; 15(1): 50, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36637621

RESUMO

Nanofibers have a wide range of applications in many fields such as energy generation and storage, environmental sensing and treatment, biomedical and health, thanks to their large specific surface area, excellent flexibility, and superior mechanical properties. With the expansion of application fields and the upgrade of application requirements, there is an inevitable trend of improving the performance and functions of nanofibers. Over the past few decades, numerous studies have demonstrated how nanofibers can be adapted to more complex needs through modifications of their structures, materials, and assembly. Thus, it is necessary to systematically review the field of nanofibers in which new ideas and technologies are emerging. Here we summarize the recent advanced strategies to improve the performances and expand the functions of nanofibers. We first introduce the common methods of preparing nanofibers, then summarize the advances in the field of nanofibers, especially up-to-date strategies for further enhancing their functionalities. We classify these strategies into three categories: design of nanofiber structures, tuning of nanofiber materials, and improvement of nanofibers assemblies. Finally, the optimization methods, materials, application areas, and fabrication methods are summarized, and existing challenges and future research directions are discussed. We hope this review can provide useful guidance for subsequent related work.

6.
ACS Appl Mater Interfaces ; 13(42): 49907-49915, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34637278

RESUMO

Two-dimensional (2D) tin halide perovskites have recently emerged as very promising materials for eco-friendly lead-free photovoltaic devices. However, the fine control of the bulky organic cations orderly embedding into the perovskite structure with a narrow quantum-well width distribution and favorable orientation is rather complicated. In this study, we proposed to introduce the F-substituted phenylethlammonium (PEA) cation (i.e., 4-fluorophenethylammonium FPEA) in 2D tin halide perovskite, which may mitigate phase polydispersity and crystal orientation, thus potentially increasing attainable charge-carrier mobility. A strong interlayer electrostatic attraction between electron-deficient F atoms and its adjacent phenyl rings aligns the crystal structure, working together with the validated dipole interaction. Therefore, the fluorination of organic cation leads to orderly self-assembly of solvated intermediates and promotes vertical crystal orientation. Furthermore, the interlayer electrostatic interaction serves as a supramolecular anchor to stabilize the 2D tin halide perovskite structure. Our work uncovers the effect of interlayer molecular interaction on efficiency and stability, which contributes to the development of stable and efficient low-toxicity perovskite solar cells.

7.
Int J Mol Med ; 48(5)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34549307

RESUMO

Sphingosine­1­phosphate (S1P) serves an important role in various physiological and pathophysiological processes, including the regulation of cell apoptosis, proliferation and survival. Sphingosine kinase 1 (SPHK1) is a lipid kinase that phosphorylates sphingosine to generate S1P. S1P has been proven to be positively correlated with chemotherapy resistance in breast cancer, colorectal carcinoma and non­small cell lung cancer. However, whether SPHK1 is involved in the development of cisplatin resistance remains to be elucidated. The present study aimed to identify the association between SPHK1 and chemoresistance in bladder cancer cells and to explore the therapeutic implications in patients with bladder cancer. Bladder cancer cell proliferation and apoptosis were determined using Cell Counting Kit­8 assays and flow cytometry, respectively. Apoptosis­related proteins were detected via western blotting. The results revealed that SPHK1 was positively correlated with cisplatin resistance in bladder cancer cells, exhibiting an antiapoptotic effect that was reflected by the downregulation of apoptosis­related proteins (Bax and cleaved caspase­3) and the upregulation of an antiapoptotic protein (Bcl­2) in SPHK1­overexpression cell lines. Suppression of SPHK1 by small interfering RNA or FTY­720 significantly reversed the antiapoptotic effect. A potential mechanism underlying SPHK1­induced cisplatin resistance and apoptosis inhibition may be activation of STAT3 via binding non­POU domain containing octamer binding. In conclusion, the present study suggested that SPHK1 displayed significant antiapoptotic effects in cisplatin­based treatment, thus may serve as a potential novel therapeutic target for the treatment for bladder cancer.


Assuntos
Cisplatino/farmacologia , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Neoplasias da Bexiga Urinária/metabolismo , Idoso , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Ligação Proteica/efeitos dos fármacos , Neoplasias da Bexiga Urinária/patologia
8.
Front Genet ; 12: 638980, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868376

RESUMO

BACKGROUND: The prognosis of renal cell carcinoma (RCC) varies greatly among different risk groups, and the traditional indicators have limited effect in the identification of risk grade in patients with RCC. The purpose of our study is to explore a glycolysis-based long non-coding RNAs (lncRNAs) signature and verify its potential clinical significance in prognostic prediction of RCC patients. METHODS: In this study, RNA data and clinical information were downloaded from The Cancer Genome Atlas (TCGA) database. Univariate and multivariate cox regression displayed six significantly related lncRNAs (AC124854.1, AC078778.1, EMX2OS, DLGAP1-AS2, AC084876.1, and AC026401.3) which were utilized in construction of risk score by a formula. The accuracy of risk score was verified by a series of statistical methods such as receiver operating characteristic (ROC) curves, nomogram and Kaplan-Meier curves. Its potential clinical significance was excavated by gene enrichment analysis. RESULTS: Kaplan-Meier curves and ROC curves showed reliability of the risk score to predict the prognosis of RCC patients. Stratification analysis indicated that the risk score was independent predictor compare to other traditional clinical parameters. The clinical nomogram showed highly rigorous with index of 0.73 and precisely predicted 1-, 3-, and 5-year survival time of RCC patients. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene set enrichment analysis (GSEA) depicted the top ten correlated pathways in both high-risk group and low-risk group. There are 6 lncRNAs and 25 related mRNAs including 36 lncRNA-mRNA links in lncRNA-mRNA co-expression network. CONCLUSION: This research demonstrated that glycolysis-based lncRNAs possessed an important value in survival prediction of RCC patients, which would be a potential target for future treatment.

9.
Biosci Rep ; 41(1)2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33289830

RESUMO

Bladder cancer is a common malignant tumour worldwide. Epithelial-mesenchymal transition (EMT)-related biomarkers can be used for early diagnosis and prognosis of cancer patients. To explore, accurate prediction models are essential to the diagnosis and treatment for bladder cancer. In the present study, an EMT-related long noncoding RNA (lncRNA) model was developed to predict the prognosis of patients with bladder cancer. Firstly, the EMT-related lncRNAs were identified by Pearson correlation analysis, and a prognostic EMT-related lncRNA signature was constructed through univariate and multivariate Cox regression analyses. Then, the diagnostic efficacy and the clinically predictive capacity of the signature were assessed. Finally, Gene set enrichment analysis (GSEA) and functional enrichment analysis were carried out with bioinformatics. An EMT-related lncRNA signature consisting of TTC28-AS1, LINC02446, AL662844.4, AC105942.1, AL049840.3, SNHG26, USP30-AS1, PSMB8-AS1, AL031775.1, AC073534.1, U62317.2, C5orf56, AJ271736.1, and AL139385.1 was constructed. The diagnostic efficacy of the signature was evaluated by the time-dependent receiver-operating characteristic (ROC) curves, in which all the values of the area under the ROC (AUC) were more than 0.73. A nomogram established by integrating clinical variables and the risk score confirmed that the signature had a good clinically predict capacity. GSEA analysis revealed that some cancer-related and EMT-related pathways were enriched in high-risk groups, while immune-related pathways were enriched in low-risk groups. Functional enrichment analysis showed that EMT was associated with abundant GO terms or signaling pathways. In short, our research showed that the 14 EMT-related lncRNA signature may predict the prognosis and progression of patients with bladder cancer.


Assuntos
Transição Epitelial-Mesenquimal/genética , RNA Longo não Codificante/genética , Neoplasias da Bexiga Urinária/patologia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , Neoplasias da Bexiga Urinária/genética
10.
Curr Med Chem ; 27(36): 6188-6207, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31237196

RESUMO

BACKGROUND: Spectroscopic imaging based on the spontaneous Raman scattering effects can provide unique fingerprint information in relation to the vibration bands of molecules. Due to its advantages of high chemical specificity, non-invasive detection capability, low sensitivity to water, and no special sample pretreatment, Raman Spectroscopic Imaging (RSI) has become an invaluable tool in the field of biomedicine and medicinal chemistry. METHODS: There are three methods to implement RSI, including point scanning, line scanning and wide-field RSI. Point-scanning can achieve two-and three-dimensional imaging of target samples. High spectral resolution, full spectral range and confocal features render this technique highly attractive. However, point scanning based RSI is a time-consuming process that can take several hours to map a small area. Line scanning RSI is an extension of point scanning method, with an imaging speed being 300-600 times faster. In the wide-field RSI, the laser illuminates the entire region of interest directly and all the images then collected for analysis. In general, it enables more accurate chemical imaging at faster speeds. RESULTS: This review focuses on the recent advances in RSI, with particular emphasis on the latest developments on instrumentation and the related applications in biomedicine and medicinal chemistry. Finally, we prospect the development trend of RSI as well as its potential to translation from bench to bedside. CONCLUSION: RSI is a powerful technique that provides unique chemical information, with a great potential in the fields of biomedicine and medicinal chemistry.


Assuntos
Diagnóstico por Imagem , Análise Espectral Raman
11.
Front Pharmacol ; 10: 1438, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849680

RESUMO

Natural products (NPs) are an important source for new drug discovery over the past decades, which have been demonstrated to be effectively used in cancer prevention, treatment, and adjuvant therapy. Many methods, such as the genomic and metabolomic approaches, immunochemistry, mass spectrometry, and chromatography, have been used to study the effects of NPs on cancer as well as themselves. Because of the advantages in specificity, sensitivity, high throughput, and cost-effectiveness, optical imaging (OI) approaches, including optical microscopic imaging and macroscopic imaging techniques have also been applied in the studies of NPs. Optical microscopic imaging can observe NPs as cancer therapeutics at the cellular level and analyze its cytotoxicity and mechanism of action. Optical macroscopic imaging observes the distribution, metabolic pathway, and target lesions of NPs in vivo, and evaluates NPs as cancer therapeutics at the whole-body level in small living animals. This review focuses on the recent advances in NPs as cancer therapeutics, with particular emphasis on the powerful use of optical microscopic and macroscopic imaging techniques, including the studies of observation of ingestion by cells, anticancer mechanism, and in vivo delivery. Finally, we prospect the wider application and future potential of OI approaches in NPs as cancer therapeutics.

12.
Neurourol Urodyn ; 37(8): 2368-2381, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30221818

RESUMO

AIMS: To evaluate the value of magnetic stimulation (MS) in patients with pelvic floor dysfunction (PFD). METHODS: The Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement was followed. We searched five databases for articles published until November 2017. Included studies investigated the effects of MS on PFD. Meta-analysis of RCTs was performed using a random effects model, and narrative analysis was undertaken where meta-analysis was not possible. RESULTS: A total of 20 studies including 1019 patients were eligible for inclusion whose level of evidence for the included studies was low. Meta-analysis of four trials comparing MS with sham intervention showed that MS was not associated with significant improvement in ICIQ-SF score (-0.52, 95%CI -1.05, 0.01; P = 0.06, I2 = 16%), QOL score (-0.27, 95%CI -0.57, 0.04; P = 0.09, I2 = 0%), number of leakages (-0.16, 95%CI -0.62, 0.29; P = 0.48, I2 = 52%), and pad test (-1.36, 95%CI -2.64, -0.08; P = 0.04, I2 = 94%). Narrative review showed that there were no convincing evidences that MS was effective for chronic pelvic floor pain, detrusor overactivity, overactive bladder, and the included RCTs had controversial results. MS may have some benefits for nocturnal enuresis and erectile dysfunction according to the trials. CONCLUSIONS: There is no convinced evidence to support the benefits of using MS in the management of PFD. The applicability of MS in the treatment of PFD remains uncertain, so larger, well-designed trials with longer follow-up periods adopted relevant and comparable outcomes are needed to be further explored to provide a definitive conclusion.


Assuntos
Magnetoterapia , Distúrbios do Assoalho Pélvico/terapia , Doença Crônica , Disfunção Erétil/terapia , Humanos , Masculino , Enurese Noturna/terapia , Dor Pélvica/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Bexiga Urinária Hiperativa/terapia
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