An integrated 4‐modality endoscopy system combining white light imaging, autofluorescence imaging, diffuse reflectance spectroscopy and Raman spectroscopy technologies was developed for in vivo endoscopic nasopharyngeal cancer detection. Both high diagnostic sensitivity (98.6%) and high specificity (95.1%) for differentiating cancer from normal tissue sites were achieved using this system combined with multivariate diagnostic algorithm, demonstrating great potential for improving real‐time, in vivo diagnosis of cancer at endoscopy. Further details can be found in the article by Duo Lin et al. ( e201700251 )
Germanium vs Silicon: All‐dielectric nanoparticles provides the heat resistance for proteins under light‐induced heating. Further details can be found in the article by Andrei A. Krasilin et al. ( e201700322 )
Trans‐scleral iontophoresis device was shown to be effective for in‐situ delivery of lutein to the retina of human donor eyes. After treatment, Resonance Raman Spectroscopy measurements demonstrated that lutein greatly enriched the inner sclera, choroid and retina. Clinical studies are going to prove if the methodology would be a valuable approach to enrich the human macular pigment and prevent local oxidative damage in patients at risk of AMD progression. Further details can be found in the article by Marco Lombardo et al. ( e201700095 ).
The biomaterial distribution and its molecular mechanism of embryonic development in Japanese medaka fish were visualized without staining using high‐speed near‐infrared imaging. It was a remarkable achievement to visualize the structures of eyes, lipid bilayer membranes, micelles, and water structural variations at the interface of different substances. Furthermore, insights on lipid metabolism and membrane functions were obtained from the biased distribution of lipoproteins and the presence of unsaturated fatty acids in the egg membrane. Further details can be found in the article by Mika Ishigaki ( e201700115 )
Fluorescence imaging studies of the processes leading to photodynamic inactivation of bacteria have been limited due to the small size of microorganisms as well as by the faint fluorescence of most photosensitizers. A versatile method based on highly‐sensitive fluorescence microscopy is presented which allows to study, in real time, the incorporation of photosensitizers inside S. aureus upon photodynamic action. The method takes advantage of the fluorescence enhancement of phenothiazine and porphyrin photosensitizers upon entering the bacterial cytosol after the cell wall has been compromised. In combination with typical assays, such as the addition of specific enhancers of reactive oxygen species, it is possible to extract mechanistic information about the pathway of photodynamic damage at the single‐cell level. Imaging experiments in deuterated buffer strongly support a Type‐I mechanism for methylene blue and a very minor role of singlet oxygen.
A new type of high‐throughput imaging flow cytometer (>20 000 cells s‐1) based upon an all‐optical ultrafast laser‐scanning imaging technique, called free‐space angular‐chirp‐enhanced delay (FACED) is reported. FACED imaging flow cytometers enables high‐throughput visualization of functional morphology of individual cells with subcellular resolution. It critically empowers largescale and deep characterization of single cells and their heterogeneity with high statistical power— an ability to become increasingly critical in single‐cell analysis adopted in a wide range of biomedical and life‐science applications. Further details can be found in the article by Wenwei Yan et al. ( e201700178 )
Raman images were used to study the effect of the contaminant chlorpyriphos‐oxon on zebrafish eye samples. Multivariate Curve Resolution‐Alternating Least Squares (MCR‐ALS) was used to obtain the distribution maps and spectral signatures of biological components present in the images analyzed. The use of MCRALS spectral signatures as starting information for Partial Least Squares‐Discriminant Analysis allowed statistical assessment of the effect of the contaminant at a specific tissue level. Further details can be found in the article by Víctor Olmos et al. ( e201700089 ).
Currently the most sensitive method for localizing lung cancers in central airways is autofluorescence bronchoscopy (AFB) in combination with white light bronchoscopy (WLB). The diagnostic accuracy of WLB + AFB for high grade dysplasia (HGD) and carcinoma in situ is variable depending on physician's experience. When WLB + AFB are operated at high diagnostic sensitivity, the associated diagnostic specificity is low. Raman spectroscopy probes molecular vibrations and gives highly specific, fingerprint‐like spectral features and has high accuracy for tissue pathology classification. In this study we present the use of a real‐time endoscopy Raman spectroscopy system to improve the specificity. A spectrum is acquired within 1 second and clinical data are obtained from 280 tissue sites (72 HGDs/malignant lesions, 208 benign lesions/normal sites) in 80 patients. Using multivariate analyses and waveband selection methods on the Raman spectra, we have demonstrated that HGD and malignant lung lesions can be detected with high sensitivity (90%) and good specificity (65%).
The internalization kinetics and intracellular spatial distribution of functionalized diatomite nanoparticles in human lung epidermoid carcinoma cell line have been investigated by confocal fluorescence and Raman microscopy. In this context, Raman imaging due to its non‐destructive, chemically selective and label‐free working principle provides evidence that the nanovectors are internalized and co‐localize with lipid environments, suggesting an endocytic internalisation route. Nanoparticle uptakes and intracellular persistence are observed up to 72 hours, without damage to cell viability or morphology. Further details can be found in the article by Stefano Managò et al. ( e201700207 )
Semiconductor nanocomposites provide advantages beyond the capability of typical fluorescent materials for cancer detection. In this work, nanowire‐based probes with dual color channels are employed to demonstrate the capacity of cancer cell detection. Purple emitting ZnO/antibody probes are applied to detect cancer cells and meanwhile TiO2/antibody probes with green light emission are applied to identify normal fibroblast cells. A series of quantitative analyses are conducted to verify the correlation between the concentrations of ZnO and TiO2 probes, cell numbers, and peak intensities of the PL spectra. The results provide a quantitative reference for developing nanowire‐based cancel cell probes.
Sensitive Escherichia coli detection based on a T4 bacteriophageimmobilized multimode microfiber is proposed and demonstrated in this article. Different modes are excited and guided in the microfiber as evanescent field that can interact with surrounding E. coli directly. The change of E. coli concentration and corresponding binding of E. coli on microfiber surface will lead to the shift of optical spectrum, which can be exploited for the application of biosensing. Further details can be found in the article by Yanpeng Li, Hui Ma, Lin Gan, et al. ( e201800012 ).
Quantitative laser‐induced breakdown spectroscopy (LIBS) is successfully used for in‐vitro analysis of early stage calcification in aortic valvular interstitial cells (VICs). LIBS results indicate 5‐fold improvement in the detection limit of calcium deposition in VICs over cell histology techniques involving staining and colorimetric calcium assays. These results can establish LIBS at the forefront of early detection of calcification in VICs for pathological studies on Calcific Aortic Valve Disease (CAVD). Further details can be found in the article by Seyyed Ali Davari et al. ( e201600288 ).
For the first time, spatially resolved quantitative metrics of light scattering recovered with sub‐diffusive spatial frequency domain imaging (sd‐SFDI) are shown to be sensitive to changes in intratumoral morphology and viability by direct comparison to histopathological analysis. Two freshly excised subcutaneous murine tumor cross‐sections were measured with sd‐SFDI, and recovered optical scatter parameter maps were co‐registered to whole mount histology. Unique clustering of the optical scatter parameters vs. γ (i.e. diffuse scattering vs. relative backscattering) evaluated at a single wavelength showed complete separation between regions of viable tumor, aggresive tumor with stromal growth, varying levels of necrotic tumor, and also peritumor muscle. The results suggest that with further technical development, sd‐SFDI may represent a non‐destructive screening tool for analysis of excised tissue or a non‐invasive approach to investigate suspicious lesions without the need for exogenous labels or spectrally resolved imaging.
Fluorescence Lifetime Imaging (FLIM) is an attractive microscopy method in the life sciences, yielding information on the sample otherwise unavailable through intensity‐based techniques. A novel Noise‐Corrected Principal Component Analysis (NC‐PCA) method for time‐domain FLIM data is presented here. The presence and distribution of distinct microenvironments are identified at lower photon counts than previously reported, without requiring prior knowledge of their number or of the dye's decay kinetics. A noise correction based on the Poisson statistics inherent to Time‐Correlated Single Photon Counting is incorporated. The approach is validated using simulated data, and further applied to experimental FLIM data of HeLa cells stained with membrane dye di‐4‐ANEPPDHQ. Two distinct lipid phases were resolved in the cell membranes, and the modification of the order parameters of the plasma membrane during cholesterol depletion was also detected.
Noise‐corrected Principal Component Analysis of FLIM data resolves distinct microenvironments in cell membranes of live HeLa cells. 相似文献
This study provides a simple method to detect human distal radius bone density based on near infrared (NIR) imaging. The information of bone mineral density can be measured by transluminational optical bone densitometric system. Compared to dual‐energy x‐ray absorptiometry (DXA) results in clinical trial, NIR images show a strong correlation to DXA. Further details can be found in the article by Chun Chung, Yu‐Pin Chen, Tsai‐Hsueh Leu, and Chia‐Wei Sun ( e201700342 ).
A multi‐wavelength prism coupling refractometer is utilized to measure the angular reflectance of freshly excised human intestinal tissue specimens. Based on reflectance data, the real and imaginary part of the refractive index is calculated via Fresnel analysis for three visible (blue, green, red) and two near‐infrared (963 nm and 1551 nm) wavelengths. Averaged values of the complex refractive index and corresponding Cauchy dispersion fits are given for the mucosa, submucosa and serosa layers of the colorectal wall at the normal state. The refractive constants of tumorous and normal mucosa are then cross‐compared for the indicative cases of one patient diagnosed with a benign polyp and three patients diagnosed with adenocarcinomas of different phenotype. Significant index contrast exists between the normal and diseased states, indicating the potential use of refractive index as a marker of colorectal dysplasia.
Eu3+integrated photoluminescence intensity ratio (PLIR) approach for optical detection of lactates in blood serum, plasma and confocal imaging of brain tissues has very high potential for exploitation of this technique in both in vitro monitoring and in vivo bioimaging applications for the detection of biomarkers in various diseases states. This image is diagrammatic representation of fact that the overall PLIR is higher with more lactates conjugated with Eu3+ ions. Further details can be found in the article by Tarun Kakkar et al. ( e201700199 ).
We proposed a side channel photonic crystal fiber (SC‐PCF) based Surface enhanced Raman spectroscopy (SERS) platform which is able to accurately monitor lipid peroxidation derived protein modifications in cells. This platform incorporates linoleamide alkyne (LAA), which is oxidized and subsequently modifies proteins in cells with alkyne functional group upon lipid peroxidation. By loading the side channel of SC‐PCF with a mixture of gold nanoparticles and LAA treated cells, and subsequently measuring the interference‐free alkyne Raman peak from these proteins in cells, strong SERS signal was obtained. The platform provides a method for the rapid monitoring of lipid peroxidation derived protein modification in cells.
We disclose a theranostic device for performing image‐guided riboflavin/UV‐A corneal cross‐linking. The device determines treatment efficacy by real time monitoring of riboflavin concentration in the corneal stroma. The study shows efficacy of the device in eye bank human donor tissues. Further details can be found in the article by Giuseppe Lombardo et al. ( e201800028 )
A hyperspectral image data cube acquired from HEK‐293 cells labeled with cytoplasmic and nuclear stains: Calcein Green and NucBlu. The top view (XY plane) displays three spectrally unmixed channels for cellular autofluorescence (red), Calcein Green (green), and NucBlue (blue). The Z axis shows spectral information, from low to high wavelength. The article by Leavesley and colleagues describes an approach for calculating the sensitivity of spectral imaging assays for detecting a fluorescence signature within a mix of other signatures or autofluorescence. Further details can be found in the article by Silas J. Leavesley et al. ( e201600227 ).
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