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1.
BMC Pulm Med ; 24(1): 42, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243217

RESUMO

BACKGROUND: Pleural disease is a common clinical condition, and some patients present with a small amount of pleural effusion or no pleural effusion. It is difficult to diagnose such patients in clinical practice. Medical thoracoscopy is the gold standard for the diagnosis of pleural effusion with unknown origin, and guidelines recommend that pneumothorax should be induced in such patients before medical thoracoscopy examination. However, the process of inducing pneumothorax is tedious and has many complications. Our study was conducted to clarify the value of thoracic ultrasound combined with medical thoracoscopy in patients with small amounts or without pleural effusion to simplify the process of medical thoracoscopy examination. METHODS: In this retrospective study, we included patients who were assigned to complete medical thoracoscopy. Successful completion of medical thoracoscopy in patients was regarded as letting the endoscope get into the pleural cavity and completion of the biopsy. Finally, we analyzed the value of preoperative ultrasound in patients without or with small amounts of pleural effusion. RESULTS: Seventy-two patients were finally included in the study. Among them, 68 patients who underwent ultrasound positioning of the access site successfully completed the examination and four patients failed the examination. Fifty-one cases showed no fluid sonolucent area at the access site, of which 48 cases had pleural sliding signs at the access site, and 47 patients successfully completed the examination; 3 cases without pleural sliding signs at the access site failed to complete thoracoscopy. In 21 cases, the fluid sonolucent area was selected as the access site, and all of them successfully completed thoracoscopy. CONCLUSION: Medical thoracoscopy is one of the methods to confirm the diagnosis in patients with pleural disease with small amounts or without pleural effusion. The application of thoracic ultrasound before medical thoracoscopy can be used for the selection of the access site. It is possible to replace pneumothorax induction before medical thoracoscopy.


Assuntos
Doenças Pleurais , Derrame Pleural , Pneumotórax , Humanos , Pneumotórax/complicações , Estudos Retrospectivos , Derrame Pleural/etiologia , Doenças Pleurais/diagnóstico , Toracoscopia/métodos , Ultrassonografia de Intervenção
2.
Int J Mol Sci ; 25(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38612614

RESUMO

Revealing the interaction mechanisms between anticancer drugs and target DNA molecules at the single-molecule level is a hot research topic in the interdisciplinary fields of biophysical chemistry and pharmaceutical engineering. When fluorescence imaging technology is employed to carry out this kind of research, a knotty problem due to fluorescent dye molecules and drug molecules acting on a DNA molecule simultaneously is encountered. In this paper, based on self-made novel solid active substrates NpAA/(ZnO-ZnCl2)/AuNPs, we use a surface-enhanced Raman spectroscopy method, inverted fluorescence microscope technology, and a molecular docking method to investigate the action of the fluorescent dye YOYO-1 and the drug DOX on calf thymus DNA (ctDNA) molecules and the influencing effects and competitive relationships of YOYO-1 on the binding properties of the ctDNA-DOX complex. The interaction sites and modes of action between the YOYO-1 and the ctDNA-DOX complex are systematically examined, and the DOX with the ctDNA-YOYO-1 are compared, and the impact of YOYO-1 on the stability of the ctDNA-DOX complex and the competitive mechanism between DOX and YOYO-1 acting with DNA molecules are elucidated. This study has helpful experimental guidance and a theoretical foundation to expound the mechanism of interaction between drugs and biomolecules at the single-molecule level.


Assuntos
Benzoxazóis , Corantes Fluorescentes , Nanopartículas Metálicas , Compostos de Quinolínio , Ouro , Simulação de Acoplamento Molecular , Análise Espectral Raman , DNA
3.
Int J Mol Sci ; 25(11)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38892371

RESUMO

The composition of skeletal muscle fiber types affects the quality of livestock meat and human athletic performance and health. L-arginine (Arg), a semi-essential amino acid, has been observed to promote the formation of slow-twitch muscle fibers in animal models. However, the precise molecular mechanisms are still unclear. This study investigates the role of Arg in skeletal muscle fiber composition and mitochondrial function through the mTOR signaling pathway. In vivo, 4-week C56BL/6J male mice were divided into three treatment groups and fed a basal diet supplemented with different concentrations of Arg in their drinking water. The trial lasted 7 weeks. The results show that Arg supplementation significantly improved endurance exercise performance, along with increased SDH enzyme activity and upregulated expression of the MyHC I, MyHC IIA, PGC-1α, and NRF1 genes in the gastrocnemius (GAS) and quadriceps (QUA) muscles compared to the control group. In addition, Arg activated the mTOR signaling pathway in the skeletal muscle of mice. In vitro experiments using cultured C2C12 myotubes demonstrated that Arg elevated the expression of slow-fiber genes (MyHC I and Tnnt1) as well as mitochondrial genes (PGC-1α, TFAM, MEF2C, and NRF1), whereas the effects of Arg were inhibited by the mTOR inhibitor rapamycin. In conclusion, these findings suggest that Arg modulates skeletal muscle fiber type towards slow-twitch fibers and enhances mitochondrial functions by upregulating gene expression through the mTOR signaling pathway.


Assuntos
Arginina , Fibras Musculares Esqueléticas , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Camundongos , Arginina/metabolismo , Arginina/farmacologia , Masculino , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Fibras Musculares de Contração Lenta/metabolismo , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Linhagem Celular
4.
Opt Lett ; 48(19): 5061-5064, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773385

RESUMO

The crucial zero-order light due to the pixelation effect of spatial light modulator (SLM) has been a serious issue in the field of light modulation, especially in applications with a high numerical aperture optical system. In this investigation, we report that by properly adjusting the high-level and low-level pixel voltages of an SLM, the zero-order light caused by the pixelation effect of an SLM can be significantly eliminated. The method is further validated under an inverted fluorescence microscope. The experimental results show that the zero-order light can be inhibited up to 91.3%, accompanied by an improvement of the modulation efficiency from 77.5% to 92.6%.

5.
Int J Mol Sci ; 24(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37686321

RESUMO

Bendamustine (BENDA) is a bifunctional alkylating agent with alkylating and purinergic antitumor activity, which exerts its anticancer effects by direct binding to DNA, but the detailed mechanism of BENDA-DNA interaction is poorly understood. In this paper, the interaction properties of the anticancer drug BENDA with calf thymus DNA (ctDNA) were systematically investigated based on surface-enhanced Raman spectroscopy (SERS) technique mainly using a novel homemade AuNPs/ZnCl2/NpAA (NpAA: nano porous anodic alumina) solid-state substrate and combined with ultraviolet-visible spectroscopy and molecular docking simulation to reveal the mechanism of their interactions. We experimentally compared and studied the SERS spectra of ctDNA, BENDA, and BENDA-ctDNA complexes with different molar concentrations (1:1, 2:1, 3:1), and summarized their important characteristic peak positions, their peak position differences, and hyperchromic/hypochromic effects. The results showed that the binding modes include covalent binding and hydrogen bonding, and the binding site of BENDA to DNA molecules is mainly the N7 atom of G base. The results of this study help to understand and elucidate the mechanism of BENDA at the single-molecule level, and provide guidance for the further development of effective new drugs with low toxicity and side effects.


Assuntos
Ouro , Nanopartículas Metálicas , Cloridrato de Bendamustina , Simulação de Acoplamento Molecular , Análise Espectral Raman , DNA
6.
Angew Chem Int Ed Engl ; 62(37): e202308029, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37469108

RESUMO

Chiral induction by natural biomolecules can reveal the indispensable role of chiral structures in life and can be used to develop the chirality-sensing biomolecular recognition. Here, we present the synthesis and characterization of an achiral supramolecular organic framework (SOF-1) constructed from cucurbit[8]uril (CB[8]) and hexaphenylbenzene (HPB) derivative (1) in water. Due to the propeller-like rotational chiral conformation of HPB units and the specific recognition properties of CB[8], SOF-1 demonstrates chiral adaptive induction in water when interacting with the N-terminal Trp-/Phe-containing dipeptides including L-TrpX and L-PheX (X is an amino acid residue), respectively, exhibiting contrasting circular dichroism (CD) and circularly polarized luminescence (CPL) spectra. Consequently, SOF-1 has been developed as a supramolecular host and chiroptical sensor capable of recognizing and distinguishing the sequence-opposite Trp-/Phe-containing dipeptide pairs including L-TrpX/L-XTrp and L-PheX/L-XPhe based on the sequence-selective CD responses.

7.
Anal Chem ; 94(35): 12231-12239, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35999194

RESUMO

Micromixer is a key element in a lab on a chip for broad applications in the analysis and measurement of chemistry and engineering. Previous investigations reported that electrokinetic (EK) turbulence could be realized in a "Y" type micromixer with a cross-sectional dimension of 100 µm order. Although the ultrafast turbulent mixing can be generated at a bulk flow Reynolds number on the order of unity, the micromixer has not been optimized. In this investigation, we systematically investigated the influence of electric field intensity, AC frequency, electric conductivity ratio, and channel width at the entrance on the mixing effect and transition electric Rayleigh number in the "Y" type electrokinetic turbulent micromixer. It is found that the optimal mixing is realized in a 350 µm wide micromixer, under 100 kHz and 1.14 × 105 V/m AC electric field, with an electric conductivity ratio of 1:3000. Under these conditions, a degree of mixedness of 0.93 can be achieved at 84 µm from the entrance and 100 ms. A further investigation of the critical electric field and the critical electric Rayleigh number indicates that the most unstable condition of EK flow instability is inconsistent with that of the optimal mixing in EK turbulence. To predict the evolution of EK flow under high Raσ and guide the design of EK turbulent micromixers, it is necessary to apply a computational turbulence model instead of linear instability analysis.

8.
Anal Chem ; 94(51): 17913-17921, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36519957

RESUMO

Nonlinearity of electroosmotic flows (EOFs) is ubiquitous and plays a crucial role in ion transport, specimen mixing, electrochemistry reaction, and electric energy storage and utilization. When and how the transition from a linear regime to a nonlinear one occurs is essential for understanding, prohibiting, or utilizing nonlinear EOF. However, due to the lack of reliable experimental instruments with high spatial and temporal resolutions, the investigation of the onset of nonlinear EOF still remains in theory. Herein, we experimentally studied the velocity fluctuations of EOFs driven by an alternating current (AC) electric field via ultrasensitive fluorescent blinking tricks. The linear and nonlinear AC EOFs are successfully identified from both the time trace and energy spectra of velocity fluctuations. The transitional electric field (EA,C) is determined by both the convection velocity (U) and AC frequency (ff) as EA,C ∼ ff0.48-0.027U. We hope the current investigation could be essential in the development of both theory and applications of nonlinear EOFs.


Assuntos
Eletricidade , Eletro-Osmose , Eletroquímica , Transporte de Íons
9.
Opt Lett ; 47(6): 1335-1338, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290307

RESUMO

In this Letter, we propose a non-iterative multifold strip segmentation phase method for a spatial light modulator (SLM) to generate multifocal spots of diverse beams (Airy, spiral, perfect vortex, and Bessel-Gaussian beams) in a high-numerical-aperture system, with up to 6D controllability. The method is further validated by an inverted fluorescence microscope. By adjusting the bright and dark voltage parameters of the SLM, zero-order light caused by the pixelation effect of the SLM has been successfully eliminated. We hope this research provides a more flexible and powerful approach for the rapid modulation of multi-focus light fields in the development of biomedicine and lithography.

10.
Langmuir ; 38(5): 1716-1724, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35089718

RESUMO

The interactions of DNA molecules and metal ions lead to changes in their configuration and conformation, which in turn influence the current characteristics of the solution as DNA molecules are translocated through a micro/nanofluidic channel and ultimately cause serious impacts on the practical applications of DNA/gene chips for precisely manipulating and studying the molecular properties of single DNA molecules. In this study, the current characteristics of λ-DNA solutions without or with metal ions (i.e., K+, Na+, Mg2+, and Ca2+) were experimentally investigated when they were transported through a 5 µm microcapillary under an external electric field with asymmetric electrodes. Experimental data indicated some meaningful results. First, the current-voltage relations of the metal ion solutions were all linear, while those of λ-DNA solutions without or with metal ions were all nonlinear and followed power functions, of which the indices were related to the type, valence, and mobility of ions. Furthermore, as the concentrations of metal ions increased, the power indices of the λ-DNA solutions with monovalent metal ions increased, while those of the λ-DNA solutions with divalent ions decreased. Finally, the main reasons for the current characteristics were theoretically attributed to two possible mechanisms: the polarizations on the asymmetric electrodes and the interactions between λ-DNA and metal ions. These findings are helpful for the design of new biomedical micro/nanofluidic sensors and labs on a chip for accurately manipulating single DNA molecules.


Assuntos
DNA , Microfluídica , Cátions Bivalentes , Íons , Metais
11.
Opt Express ; 29(6): 8698-8709, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820312

RESUMO

In this investigation, we propose a strip segmentation phase (SSP) method for a spatial light modulator (SLM) to generate independent multifocal spots when the beam passes through a high numerical aperture (NA) lens. With the SSP method, multifocal spots can be generated with each spot independently, flexibly and uniformly distributed. The performance of the SSP method is first validated with numerical simulation. Then, by applying the modulation method with SLM and importing the beams into an inverted fluorescence microscopy system with a high-NA lens, the spot distribution and their shapes can be observed by fluorescent image. The fluorescent image exhibits high uniformity and high consistency with the aforementioned numerical simulations. Finally, we dynamically load a series of phase maps on SLM to realize continuous and independent spot movement in a multifocal array. By laser direct writing on photoresist, a complex NWU-shape structure can be realized flexibly with multi-task fabrication capability. The SSP method can significantly improve the efficiency and flexibility of laser direct writing. It is also compatible with most recent techniques, e.g., multiphoton absorption, stimulated emission depletion and photo-induced depolymerization etc., to realize parallel super-resolution imaging and fabrications.

12.
Opt Lett ; 46(21): 5389-5392, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34724483

RESUMO

Computational ghost imaging or single-pixel imaging enables the image formation of an unknown scene using a lens-free photodetector. In this Letter, we present a computational panoramic ghost imaging system that can achieve a full-color panorama using a single-pixel photodetector, where a convex mirror performs the optical transformation of the engineered Hadamard-based circular illumination pattern from unidirectionally to omnidirectionally. To our best knowledge, it is the first time to propose the concept of ghost panoramas and realize preliminary experimentations. It is foreseeable that ghost panoramas will have more advantages in imaging and detection in many extreme conditions (e.g., scattering/turbulence and unconventional spectra), as well as broad application prospects.

13.
Langmuir ; 37(18): 5457-5463, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33900784

RESUMO

A ZnO/ZnCl2 composite with stable 3D structural morphologies and long lasting superhydrophilicity was synthesized on the top surface of a nano porous anodic alumina (nanoPAA) substrate. The wettability of a nanoPAA-ZnO/ZnCl2 was systematically characterized and the experimental data indicated that the water contact angle (WCA) of 0° could be achieved as well as maintained over 7 days and still remained at 4.36° after 50 days, and its 3D structural morphology had no clearly observable change during this period. The mechanism for the superhydrophilicity of the composites was interpreted in terms of the inherent hydrophilicity of ZnO/ZnCl2 nanofilm, the three-dimensional structures of wrinkled nanoflakes, the nanogaps between neighbor nanoflakes, the difference of structual morphologies (i.e., size, shape, and upright posture of nanoflakes), and the measured True Volume of voids in the nanocomposite. The structural morphologies were mainly determined by the parameters such as the original concentration of precursor ZnCl2 and the pore diameter of nanoPAA substrate. The study proposes a promising superhydrophilic nanomaterial and a cost-effective synthesis method, which will play a practical role in the fields of biomedical molecular sensors and micro/nanofluidic chips.

14.
J Microsc ; 282(3): 239-249, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33443815

RESUMO

The interface of mediums with refractive indices discontinuous, for example air-glass and glass-water, are inevitable in microscopic imaging. In this work, the aberration of oblique interface with refractive index discontinuous on the laser scanning microscope was investigated theoretically with numerical simulations. It was found that the position, shape and FWHM of focal spots, were all significantly affected by the aberration due to oblique interface. The aberration can cause serious shifting of focal spots in the axial direction of beam during z -scanning and lead to an inaccurate reconstruction of three-dimensional (3D) targets. The aberration can also lead to a decreasing spatial resolution. To correct the influence of the aberration, a pure-phase modulation method has been proposed. By applying a phase compensation map into a spatial light modulator (SLM), the oblique interface aberration had been corrected experimentally in a laser scanning microscope. We hope this research can attract the attention of researchers when using scanning microscope, especially for reconstructing 3D biological and material structures.


Assuntos
Refratometria , Microscopia Confocal
15.
BMC Pulm Med ; 21(1): 84, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33711958

RESUMO

BACKGROUND: Crazy-paving patterns are rarely reported as radiological manifestations of pulmonary cryptococcosis. CASE PRESENTATION: Herein, we presented a very rare case of a crazy-paving pattern as a radiological manifestation of pulmonary cryptococcosis in a patient with primary ciliary dyskinesia. The diagnosis of pulmonary cryptococcosis and primary ciliary dyskinesia was ultimately confirmed by bronchoscopic biopsy, fungus culture, whole exome sequencing of blood, etc. The patient received flucytosine (PO, 5 g per day) and amphotericin B (IV, 70 mg per day) during hospitalization and sequential therapy with voriconazole (PO, 200 mg twice a day) after discharge. He recovered during follow-up. CONCLUSIONS: We concluded that pulmonary cryptococcosis should be considered a possible cause of crazy-paving patterns in chest CT scans.


Assuntos
Criptococose/patologia , Pneumopatias Fúngicas/patologia , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Broncoscopia , Criptococose/diagnóstico por imagem , Criptococose/tratamento farmacológico , Flucitosina/administração & dosagem , Humanos , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Voriconazol/administração & dosagem
16.
Int J Med Sci ; 17(5): 577-590, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210707

RESUMO

Confocal Raman microspectral imaging was adopted to elucidate the cellular drug responses of osteosarcoma cells (OC) to N-[N-(3, 5-difluorophenyl acetyl)-L-alanyl]-sphenylglycine butyl ester (DAPT), a γ-secretase inhibitor, by identifying the drug induced subcellular compositional and structural changes. Methods: Spectral information were acquired from cultured osteosarcoma cells treated with 0 (Untreated Group, UT), 10 (10 µM DAPT treated, 10T), 20 µM (20 µM DAPT treated, 20T) DAPT for 24 hours. A one-way ANOVA and Tukey's honest significant difference (HSD) post hoc multiple test were sequentially applied to address spectral features among three groups. Multivariate algorithms such as K-means clustering analysis (KCA) and Principal component analysis (PCA) were used to highlight the structural and compositional differences, while, univariate imaging was applied to illustrate the distribution pattern of certain cellular components after drug treatment. Results: Major biochemical changes in DAPT-induced apoptosis came from changes in the content and structure of proteins, lipids, and nucleic acids. By adopted multivariate algorithms, the drug induced cellular changes was identified by the morphology and spectral characteristics between untreated cells and treated cells, testified that DAPT mainly acted in the nuclear region. With the increase of the drug concentration, the content of main subcellular compositions, such nucleic acid, protein, and lipid decreased. In an addition, DAPT-induced nuclear fragmentation and apoptosis was depicted by the univariate Raman image of major cellular components (nucleic acids, proteins and lipids). Conclusions: The achieved Raman spectral and imaging results illustrated detailed DAPT-induced subcellular compositional and structural variations as a function of drug dose. Such observations can not only explain drug therapeutic mechanisms of OC DAPT treatment, and also provide new insights for accessing the medicine curative efficacy and predicting prognosis.


Assuntos
Estruturas Celulares/efeitos dos fármacos , Dipeptídeos/farmacologia , Osteossarcoma/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Dipeptídeos/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos , Osteossarcoma/química , Análise de Componente Principal , Análise Espectral Raman
17.
Med Sci Monit ; 26: e920355, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32208405

RESUMO

BACKGROUND Esophageal cancer is a malignant tumor with a complex pathogenesis and a poor 5-year survival rate, which encourages researchers to explore its molecular mechanisms deeper to improve the prognosis. MATERIAL AND METHODS DEGs were from 4 Gene Expression Omnibus (GEO) databases (GSE92396, GSE20347, GSE23400, and GSE45168) including 87 esophageal tumor samples and 84 normal samples. We performed Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Protein-Protein interaction (PPI) analysis, and GeneMANIA to identify the DEGs. Gene set enrichment analysis (GSEA) and Kaplan-Meier survival analyses were performed. RESULTS There was an overlapping subset consisting of 120 DEGs that was present in all esophageal tumor samples. The DEGs were enriched in extracellular matrix (ECM)-receptor interaction, as well as focal adhesion and transcriptional mis-regulation in cancer. The 2 most crucial regulatory pathways in esophageal cancer were the amebiasis pathway and the PI3K-Akt signaling pathway. Secreted phosphoprotein 1 (SPP1) and fibronectin 1 (FN1) were selected and verified in an independent cohort and samples using the TCGA and GTEx projects. Gene set enrichment analysis (GSEA) showed that proteasome and nucleotide excision repair were 2 most differentially enriched pathways in the SPP1 high-expression phenotype, and ECM-receptor interaction and focal adhesion in FN1 high-expression phenotype. Kaplan-Meier survival analysis showed that SPP1 and FN1 were significantly positively related to overall survival and had the potential to predict patient relapse. CONCLUSIONS Our analysis is the first to show that SPP1 and FN1 might work as biological markers of progression and prognosis in esophageal carcinoma (ESCA).


Assuntos
Neoplasias Esofágicas/genética , Fibronectinas/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Osteopontina/genética , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Adesões Focais/metabolismo , Ontologia Genética , Humanos , Estimativa de Kaplan-Meier , Osteopontina/metabolismo , Fosfoinositídeo Fosfolipase C/genética , Fosfoinositídeo Fosfolipase C/metabolismo , Prognóstico , Reprodutibilidade dos Testes , Análise de Sobrevida
18.
Opt Express ; 27(25): 36505-36523, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873428

RESUMO

In previous single-pixel imaging systems, the light source was generally idle with respect to time. Here, we propose a novel image fusion and visible watermarking scheme based on Fourier single-pixel imaging (FSPI) with a multiplexed time-varying (TV) signal, which is generated by the watermark pattern hidden in the light source. We call this scheme TV-FSPI. With TV-FSPI, we can realize high-quality visible image watermarking, encrypted image watermarking and full-color visible image watermarking. We also discuss the extension to invisible watermarking based on TV-FSPI. Furthermore, we don't have to recode illumination patterns, because TV-FSPI can be extended to existing mainstream illumination patterns, such as random illumination mode and Hadamard illumination mode. Thus TV-FSPI has the potential to be used in single-pixel broadcasting system and multi-spectral single-pixel imaging system.

19.
Appl Microbiol Biotechnol ; 103(16): 6759-6769, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31230100

RESUMO

Confocal Raman microspectral imaging (CRMI) is an advanced cell-imaging method that maps endogenous molecular compositions with their unique spectral fingerprint indicators. The aim of this work was to provide a visualized understanding of subcellular features of live osteosarcoma cells using a 532-nm laser excitation without the use of dyes or molecular probes. Both malignant osteoblast and spindle osteosarcoma cells derived from the BALB/c mouse osteosarcoma cell line K7M2 were investigated in this work. After preprocessing the obtained spectral dataset, K-means cluster analysis (KCA) is employed to reconstruct Raman spectroscopic maps of single biological cells by identifying regions of the cellular membrane, cytoplasm, organelles, and nucleus with their corresponding mean spectra. Principal component analysis (PCA) was further employed to indicate variables of significant influence on the separation of the spectra of each cellular component. The biochemical components of the two cell types were then extracted by showing the spectral and distribution features attributed to proteins, lipids, and DNA. Using this standardized CRMI technique and multivariate analysis approaches, the results obtained could be a sound foundation for a typical Raman imaging protocol of live cellular biomedical analysis.


Assuntos
Fatores Biológicos/análise , Linhagem Celular Tumoral/química , Microscopia Óptica não Linear/métodos , Osteossarcoma/patologia , Análise de Célula Única/métodos , Animais , Camundongos , Camundongos Endogâmicos BALB C , Análise Multivariada
20.
Appl Opt ; 58(8): 2112-2120, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30874075

RESUMO

Probing depth and system aberrations have direct impacts on the spatial resolution of stimulated emission depletion (STED) microscopes. Based on the vectorial diffraction theory, the influence of coma and astigmatism on the focal patterns of STED microscopes in probing stratified mediums with discontinuous refractive indices (e.g., glass cover slip, solution, and biological samples, etc.) have been illustrated in detail. The spatial resolution of the STED system has been discussed by analyzing the full width at half-maximum size of the fluorescence spots. It is found that, while probing in stratified media with discontinuous refractive indices, the spatial resolution of a STED microscope can be very sensitive to the existence of aberrations, e.g., coma and astigmatism, at different probing depths, as a result of mismatched axial positions of the excitation and depletion patterns. The spatial resolution of STED can be degraded up to 1.87- and 1.95-fold compared to that without aberrations. Therefore, a careful evaluation of the influence of aberration and discontinuous refractive indices should be taken into account when applying a STED microscope to realize super-resolution images.

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