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1.
M.S. Pochechuev I.V. Fedotov O.I. Ivashkina M.A. Roshchina K.V. Anokhin A.M. Zheltikov 《Journal of biophotonics》2018,11(1)
Optical coupling between a single, individually addressable neuron and a properly designed optical fiber is demonstrated. Two‐photon imaging is shown to enable a quantitative in situ analysis of such fiber–single‐neuron coupling in the live brain of transgenic mice. Fiber‐optic interrogation of single pyramidal neurons in mouse brain cortex is performed with the positioning of the fiber probe relative to the neuron accurately mapped by means of two‐photon imaging. These results pave the way for fiber‐optic interfaces to single neurons for a stimulation and interrogation of individually addressable brain cells in chronic in vivo studies on freely behaving transgenic animal models, as well as the integration of fiber‐optic single‐neuron stimulation into the optical imaging framework.
2.
Measurement of optical properties of pig esophagus by using a modified spectrometer set‐up 下载免费PDF全文
Martin Hohmann B. Lengenfelder R. Kanawade F. Klämpfl A. Douplik H. Albrecht 《Journal of biophotonics》2018,11(1)
Optical properties (μa, μs and g) of certain human tissue types such as skin and blood have been very well investigated. However until today, for internal body organs such as the esophagus they are not well characterized. For ex‐vivo measurements “Inverse Adding Doubling” (IAD) and Inverse Monte‐Carlo‐Simulation (IMCS) are state of the art. Both methods need the measurement of the collimated transmission. Current methods lack a proper way of measuring the collimated transmission. Hence, this measurement of the g‐factor has a systematic error. Therefore, for the measurement of the collimated transmission, a new approach has been developed and evaluated with intralipid. Finally, the optical properties of mucosa, sub mucosa, muscularis and adventitia of pig esophagus tissue are calculated with IAD. The results are promising and in agreement with published literature.
3.
Alzheimer mouse brain tissue measured by time resolved fluorescence spectroscopy using single‐ and multi‐photon excitation of label free native molecules 下载免费PDF全文
Time resolved spectroscopic measurements with single‐photon and multi‐photon excitation of native molecules were performed ex vivo on brain tissues from an Alzheimer's disease (AD) and a wild type (WT) mouse model using a streak camera. The fluorescence decay times of native NADH and FAD show a longer relaxation time in AD than in WT tissue, suggesting less non‐radiative processes in AD. The longer emission time of AD may be attributed to the coupling of the key native building block molecules to the amyloid‐tau and/or to the caging of the native fluorophores by the deposition of amyloid‐beta or tau plaques and neurofibrillary tangles that affect the local non‐radiative interactions.
4.
High sensitivity non‐invasive detection of calcifications deep inside biological tissue using Transmission Raman Spectroscopy 下载免费PDF全文
The aim of this research was to develop a novel approach to probe non‐invasively the composition of inorganic chemicals buried deep in large volume biological samples. The method is based on advanced Transmission Raman Spectroscopy (TRS) permitting chemical specific detection within a large sampling volume. The approach could be beneficial to chemical identification of the breast calcifications detected during mammographic X‐ray procedures. The chemical composition of a breast calcification reflects the pathology of the surrounding tissue, malignant or benign and potentially the grade of malignancy. However, this information is not available from mammography, leading to excisional biopsy and histopathological assessment for a definitive diagnosis. Here we present, for the first time, a design of a new high performance deep Raman instrument and demonstrate its capability to detect type II calcifications (calcium hydroxyapatite) at clinically relevant concentrations and depths of around 40 mm in phantom tissue. This is around double the penetration depth achieved with our previous instrument design and around two orders of magnitude higher than that possible when using conventional Raman spectroscopy.
5.
In‐vitro analysis of early calcification in aortic valvular interstitial cells using Laser‐Induced Breakdown Spectroscopy (LIBS) 下载免费PDF全文
Calcific aortic valve disease (CAVD) is a major cardiovascular disorder caused by osteogenic differentiation of valvular interstitial cells (VICs) within aortic valves. Conventional methods like colorimetric assays and histology fail to detect small calcium depositions during in‐vitro VIC cultures. Laser‐induced breakdown spectroscopy (LIBS) is a robust analytical tool used for inorganic materials characterizations, but relatively new to biomedical applications. We employ LIBS, for the first time, for quantitative in‐vitro detection of calcium depositions in VICs at various osteogenic differentiation stages. VICs isolated from porcine aortic valves were cultured in osteogenic media over various days. Colorimetric calcium assays based on arsenazo dye and Von Kossa staining measured the calcium depositions within VICs. Simultaneously, LIBS signatures for Ca I (422.67 nm) atomic emission lines were collected for estimating calcium depositions in lyophilized VIC samples. Our results indicate excellent linear correlation between the calcium assay and our LIBS measurements. Furthermore, unlike the assay results, the LIBS results could resolve calcium signals from cell samples with as early as 2 days of osteogenic culture. Quantitatively, the LIBS measurements establish the limit of detection for calcium content in VICs to be ~0.17±0.04 μg which indicates a 5‐fold improvement over calcium assay. Picture : Quantitative LIBS enables in‐vitro analysis for early stage detection of calcium deposition within aortic valvular interstitial cells (VICs).
6.
Alexandra Sorvina Christie A. Bader Mitchell C. Lock Douglas A. Brooks Janna L. Morrison Sally E. Plush 《Journal of biophotonics》2018,11(1)
Coronary heart disease is one of the largest causes of death worldwide, making this a significant health care issue. A critical problem for the adult human heart is that it does not undergo effective repair in response to damage, leaving patients with a poor prognosis. Unlike the adult, fetal hearts have the ability to repair after myocardial damage. Using two‐photon microscopy, we have visualised the morphological and metabolic changes following myocardial infarction in sheep fetuses, to characterise response to cardiac injury in a mammalian model. Following myocardial infarction, fetal hearts showed no significant increase in collagen deposition in the region of the infarction, when compared to either the surrounding tissue or shams. In contrast, metabolic activity (i. e. NAD(P)H and FAD) was significantly reduced in the region of myocardial infarction, when compared to either the surrounding tissue or sham hearts. For comparison, we also imaged two hearts from preadolescent sheep (sham and myocardial infarction) and showed highly ordered collagen deposition with decreased metabolic activity within the infarcted area. Therefore, two‐photon imaging had the capacity to image both morphological and metabolic changes in response to myocardial infarction and showed differences in the response with age. Picture : Two‐photon imaging of myocardial infarction ( b and d ) enabled the visualisation of increased collagen (blue; Em=431 nm) and changes in other tissue autofluorescence (green; Em=489–606 nm) in fetal ( a and b ) and preadolescent ( c and d ) hearts, compared to shams ( a and c ). The excitation wavelength was 840 nm. Scale bars: 10 μm.
7.
Amy T. Shah Taylor M. Cannon James N. Higginbotham Robert J. Coffey Melissa C. Skala 《Journal of biophotonics》2017,10(8):1026-1033
Clinical cancer treatment aims to target all cell subpopulations within a tumor. Autofluorescence microscopy of the metabolic cofactors NAD(P)H and FAD has shown sensitivity to anti‐cancer treatment response. Alternatively, flow cytometry is attractive for high throughput analysis and flow sorting. This study measures cellular autofluorescence in three flow cytometry channels and applies cellular autofluorescence to sort a heterogeneous mixture of breast cancer cells into subpopulations enriched for each phenotype. Sorted cells were grown in culture and sorting was validated by morphology, autofluorescence microscopy, and receptor expression. Ultimately, this method could be applied to improve drug development and personalized treatment planning.
8.
Back Cover: Autofluorescence and white light imaging‐guided endoscopic Raman and diffuse reflectance spectroscopy for in vivo nasopharyngeal cancer detection (J. Biophotonics 4/2018) 下载免费PDF全文
Jianji Pan Zhihong Xu Rong Chen Shangyuan Feng Guannan Chen Yongzeng Li Michael Short Jianhua Zhao Yasser Fawzy Haishan Zeng 《Journal of biophotonics》2018,11(4)
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 )
9.
Back Cover: In‐vitro analysis of early calcification in aortic valvular interstitial cells using Laser‐Induced Breakdown Spectroscopy (LIBS) (J. Biophotonics 1/2018) 下载免费PDF全文
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 ).
10.
High‐resolution deep functional imaging of the whole mouse brain by photoacoustic computed tomography in vivo 下载免费PDF全文
Pengfei Zhang Lei Li Li Lin Peng Hu Junhui Shi Yun He Liren Zhu Yong Zhou Lihong V. Wang 《Journal of biophotonics》2018,11(1)
Photoacoustic computed tomography (PACT) is a non‐invasive imaging technique offering high contrast, high resolution, and deep penetration in biological tissues. We report a PACT system equipped with a high frequency linear transducer array for mapping the microvascular network of a whole mouse brain with the skull intact and studying its hemodynamic activities. The linear array was scanned in the coronal plane to collect data from different angles, and full‐view images were synthesized from the limited‐view images in which vessels were only partially revealed. We investigated spontaneous neural activities in the deep brain by monitoring the concentration of hemoglobin in the blood vessels and observed strong interhemispherical correlations between several chosen functional regions, both in the cortical layer and in the deep regions. We also studied neural activities during an epileptic seizure and observed the epileptic wave spreading around the injection site and the wave propagating in the opposite hemisphere.
11.
Imaging blood flow inside highly scattering media using ultrasound modulated optical tomography 下载免费PDF全文
We report the use of ultrasound modulated optical tomography (UOT) with heterodyne parallel detection to locally sense and image blood flow deep inside a highly scattering medium. We demonstrate that the UOT signal is sensitive to the speed of the blood flow in the ultrasound focus and present an analytical model that relates UOT signals to the optical properties (i. e. scattering coefficient, anisotropy, absorption, and flow speed) of the blood and the background medium. We found an excellent agreement between the experimental data and the analytical model. By varying the integration time of the camera in our setup, we were able to spatially resolve blood flow in a scattering medium with a lateral resolution of 1.5 mm.
12.
Inside Back Cover: In vivo full‐field functional optical hemocytometer (J. Biophotonics 2/2018) 下载免费PDF全文
Fuli Zhang Mingyi Wang Dingan Han Haishu Tan Guojian Yang Yaguang Zeng 《Journal of biophotonics》2018,11(2)
Full‐field functional optical hemocytometer (FFOH), based on the absorption intensity fluctuation modulation (AIFM) effect, is in vivo label‐free image method for capillaries of near‐transparent live biological specimens. FFOH can provide a flow video, flow velocity measurement and RBC count, simultaneously. The zebrafish experimental result shows the potential to study the physiological mechanisms of the blood circulation systems. Further details can be found in the article by Fuli Zhang et al. ( e201700039 )
13.
Inside Front Cover: Near‐infrared bone densitometry: A feasibility study on distal radius measurement (J. Biophotonics 7/2018) 下载免费PDF全文
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 ).
14.
Wei‐Jen Li Yung‐Tsan Chen Po‐Hao Huang Tsung‐Lin Yang Jian‐Jang Huang 《Journal of biophotonics》2017,10(1):92-97
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.
15.
IR‐spectroscopy of skin in vivo: Optimal skin sites and properties for non‐invasive glucose measurement by photoacoustic and photothermal spectroscopy 下载免费PDF全文
Alexander Bauer Otto Hertzberg Arne Küderle Dominik Strobel Miguel A. Pleitez Werner Mäntele 《Journal of biophotonics》2018,11(1)
We have reported two methods to analyze glucose in the interstitial fluid of skin based on mid‐infrared excitation with a tunable quantum cascade laser and photoacoustic or photothermal detection. These methods were evaluated for optimum skin locations to obtain reproducible glucose information. The lower part of the arm, the hypothenar, the tips of the index finger and the thumb were tested. The thumb appears to be the optimal skin location, followed by the index finger. Basic requirements for an optimum site are good capillary blood perfusion, low Stratum corneum thickness and the absence of fat layers. To obtain a correlation on such a site, spectra were recorded on volunteers continuously after blood glucose manipulation. However, continuous measurements on an in vivo sample such as the skin have to cope with physiological alterations such as the formation of sweat. We have used both detection schemes to investigate the acid mantle reformation after washing during time scales similar to continuous measurements for calibration spectra. We found that reconstitution of the acid mantle of skin may be seen in less than one hour. Precleaning of the measurement site may thus be useful for intermittent, but not for long term continuous measurements.
16.
Doxorubicin kinetics and effects on lung cancer cell lines using in vitro Raman micro‐spectroscopy: binding signatures,drug resistance and DNA repair 下载免费PDF全文
Zeineb Farhane Franck Bonnier Orla Howe Alan Casey Hugh J. Byrne 《Journal of biophotonics》2018,11(1)
Raman micro‐spectroscopy is a non‐invasive analytical tool, whose potential in cellular analysis and monitoring drug mechanisms of action has already been demonstrated, and which can potentially be used in pre‐clinical and clinical applications for the prediction of chemotherapeutic efficacy. To further investigate such potential clinical application, it is important to demonstrate its capability to differentiate drug mechanisms of action and cellular resistances. Using the example of Doxorubicin (DOX), in this study, it was used to probe the cellular uptake, signatures of chemical binding and subsequent cellular responses, of the chemotherapeutic drug in two lung cancer cell lines, A549 and Calu‐1. Multivariate statistical analysis was used to elucidate the spectroscopic signatures associated with DOX uptake and subcellular interaction. Biomarkers related to DNA damage and repair, and mechanisms leading to apoptosis were also measured and correlated to Raman spectral profiles. Results confirm the potential of Raman spectroscopic profiling to elucidate both drug kinetics and pharmacodynamics and differentiate cellular drug resistance associated with different subcellular accumulation rates and subsequent cellular response to DNA damage, pointing towards a better understanding of drug resistance for personalised targeted treatment.
17.
Front Cover: A high‐throughput all‐optical laser‐scanning imaging flow cytometer with biomolecular specificity and subcellular resolution (J. Biophotonics 2/2018) 下载免费PDF全文
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 )
18.
Label‐free and non‐invasive monitoring of porcine trophoblast derived cells: differentiation in serum and serum‐free media 下载免费PDF全文
Qifei Li Edison Suasnavas Lifu Xiao Sierra Heywood Xiaojun Qi Anhong Zhou S. Clay Isom 《Journal of biophotonics》2015,8(8):638-645
Traditional approaches to characterize stem cell differentiation are time‐consuming, lengthy and invasive. Here, Raman microspectroscopy (RM) and atomic force microscopy (AFM) – both considered as non‐invasive techniques – are applied to detect the biochemical and biophysical properties of trophoblast derived stem‐like cells incubated up to 10 days under conditions designed to induce differentiation. Significant biochemical and biophysical differences between control cells and differentiated cells were observed. Quantitative real time PCR was also applied to analyze gene expression. The relationship between cell differentiation and associated cellular biochemical and biomechanical changes were discussed.
19.
Actin, cytoskeleton protein forming microfilaments, play a crucial role in cellular motility. Here we show that exposure to very low levels of polarized light guide their orientation in‐vivo within the live cell. Using a simple model to describe the role of actin‐filament orientation in directional cellular motion, we demonstrate that the actin polymerization/depolymerization mechanism develops primarily along this direction and, under certain conditions, can lead to guidance of the cell movement. Our results also show a dose dependent increase in actin activity in direct correspondence to the level of laser irradiance. We found that total expression of Tau protein, which stabilize microtubules, was decreased by the irradiance, indicating that exposure to the light may change the activity of kinase, leading to increased cell activity.
20.
Rani Toll John Joakim Henricson Gert E Nilsson Daniel Wilhelms Chris D. Anderson 《Journal of biophotonics》2018,11(1)
To use Bioengineering methodology is used to achieve, at five anatomical sites, a detailed, quantitative assessment of the return of blood content to the blanched area, during the Capillary Refill (CR) test. An observational, non‐randomized, experimental study on 23 healthy subjects (14 females) was performed in our climate controlled skin physiology laboratory. Our main outcome measures were based on the chronological assessment and quantification of red blood cell concentration (RBC) after the release of blanching pressure in the CR test, using Tissue Viability Imaging (TiVi), a digital photographic technique based on polarisation spectroscopy. TiVi enabled collection of detailed data on skin RBC concentration during the CR test. The results were shown as curves with skin blood concentration (TiVi‐value) on the y‐axis and the time on the x‐axis. Quantitative CR responses showed site and temperature variability. We also suggest possible objective endpoint values from the capillary refill curve. Detailed data on skin RBC concentration during the CR test is easily obtained and allows objective determination of end points not possible to achieve by naked eye assessment. These findings have the potential to place the utility of the CR test in a clinical setting in a new light. Picture : Regular photograph and TiVi Image showing CR test and corresponding graph for the CR response.