An optical fan was demonstrated to screen leukemia cells from the blood sample at the single‐cell level in a noninvasive and noncontact manner. Further details can be found in the article by Xiaoshuai Liu, Yuchao Li, Xiaohao Xu, Yao Zhang, Baojun Li ( e201900155 ).
A type of compact and cost‐effective light‐sheet imaging device, termed sub‐voxel‐resolving light‐sheet add‐on module (SLAM), is developed to cooperate with conventional 2D epifluorescence microscope, allowing high‐contrast, resolution‐improved 3D imaging of various biological samples at high throughput. Further details can be found in the article by Fang Zhao, Yicong Yang, Yi Li, et al. ( e201960243 ).
This study proposed a Sparse‐Graph Manifold Learning (SGML) method to balance the sparseness and morphology preserving for bioluminescence tomography reconstruction. It inherits the benefits of non‐convex sparsity constraint and dynamic Laplacian graph model. The results of numerical simulations and in vivo experiments demonstrate that the proposed method yields accurate and robust results in terms of tumor spatial location and morphology recovery. Further details can be found in the article by Hongbo Guo, Ling Gao, Jingjing Yu, et al. ( e201960218 )
A false‐colored and merged image of fresh, ex vivo rat kidney acquired using an excitation‐scanning hyperspectral imaging system. The spectral image was acquired using excitation wavelengths from 360 to 550 nm. Colors represent principal components extracted from a spectral image cube featuring no added labels or markers. Further details can be found in the article by Peter F. Favreau, Joshua A. Deal, Bradley Harris, et al. ( e201900183 ).
The figure shows the detailed morphology of vasculature and dynamic changes of the blood vessel diameter and density and the oxygen saturation in the blood vessels in fetal brain after acute prenatal ethanol exposure in the second‐trimester equivalent murine model obtained using a real‐time photoacoustic tomography (PAT) system. Further details can be found in the article by Tianqi Shan, Yuan Zhao, Shixie Jiang, Huabei Jiang ( e201960161 ).
Transcranial photobiomodulation (tPBM) with wavelength at 808 nm was applied to a rat model of acute seizures. The tPBM successfully attenuated convulsive status epilepticus, and the tPBM was shown to reduce the apoptosis of parvalbumin‐positive interneurons (PV‐INs) and preserved the integrity of perisomatic inhibitory network of PV‐INs to principle cells in the hippocampus. Further details can be found in the article by Chung‐Min Tsai, Shwu‐Fen Chang, and Hsi Chang ( e202000095 ).
This study presents a novel intraoperative in vivo imaging approach which harnessed Cerenkov luminescence (CL) to detect primary and metastatic colorectal cancer (CRC) using clinically approved radiopharmaceuticals. In the mice and swine experiments, the proposed approach effectively improved the effect of CRC surgery. The approach is believed to be promising for utilizing CL in open surgery. Further details can be found in the article by Zeyu Zhang, Yawei Qu, Yu Cao et al. ( e201960152 )
This work addresses an unmet clinical need, that of glaucoma monitoring through intraocular pressure (IOP) interrogation in patients with artificial corneas (keratoprost hesis). We demonstrate direct integration of a low‐drift, fiber‐optic Fabry‐Perot pressure sensor embedded in the keratoprosthesis via rapid, non‐contact micromagnetic fiber alignment. IOP interrogation is achieved by using white‐light interferometry, which provides sub‐mmHg IOP sensitivity. Further details can be found in the article by Pui‐Chuen Hui, Katia Shtyrkova, Chengxin Zhou, et al. ( e202000031 ).
The family of vibrational spectroscopic imaging techniques grows every few years and there is a need to compare and contrast new modalities with the better understood ones. Three vibrational spectroscopy techniques (High Definition FT‐IR, Raman and AFM‐IR) were applied for subcellular chemical imaging of cholesteryl esters in PC‐3 prostate cancer cells. The techniques were compared and contrasted in terms of image quality, spectral pattern, and chemical information. Further details can be found in the article by Maciej Roman, Tomasz P. Wrobel, Czeslawa Paluszkiewicz, and Wojciech M. Kwiatek ( e201960094 ).
iSERS (SERS=surface‐enhanced Raman scattering) microscopy is an emerging Raman‐based staining technique for the selective localization of target proteins on cells and tissues using antibody‐ SERS nanotag conjugates. In this contribution we demonstrate the feasibility of iSERS for imaging of programmed cell death‐ligand 1 (PD‐L1), an important predictive biomarker, on single SkBr‐3 breast cancer cells. Further details can be found in the article by Elzbieta Stepula, Matthias König, Xin‐Ping Wang, et al. ( e201960034 ).
Intraoperative neurosurgical diagnosis of brain tumor determines the success rate of patients' prognoses. We firstly proposed a novel approach based on an optical method to distinguish the site of the tumor functionally. The promoted technique is non‐invasive, non‐radioactive, dye‐free, and potential of real‐time monitoring, which is still not available nowadays by using other techniques. The method could be applied to neuroimage guiding system for precision surgery of brain. Further details can be found in the article by Xin‐Rui Liu, Tien‐Yu Hsiao, Yun‐Qian, et al. ( e201900200 ).
A new high‐speed cellular imaging method using clinically applicable moxifloxacin labeling, called as moxifloxacin based confocal microscopy (MBCM), was developed for fast and sensitive tumor detection and delineation. The MBCM demarcated malignant brain tumor from normal brain by visualizing dense and irregular cell distribution in the tumor. An image processing algorithm was developed for automated brain tumor detection. Further details can be found in the article by Seunghun Lee, Won Yeong Park, Hoonchul Chang, et al. ( e201900197 ).
The first post-pandemic face-to-face international conference in Biophotonics took place in Porto in April 2022. High quality and inspiring presentations have been delivered by leading scientists and internationally recognized professionals, standing on the forefront of Biophotonics research and representing broadness of the field. A selected number of these presentations resulted in the papers that are presented in this special issue. The cover images were selected from Hoffer et al., Lomanovskaya et al., Li et al., and Burton et al. (clockwise).
We report on an attempt to increase the therapeutic effect of photodynamic therapy using a lipid nanoparticle (LNP). The findings indicate that the internal structure of the LNPs change depending on the amount of photosensitizer in the particle. The photoactivity and cell-killing effect of photosensitizer also changed with increasing amount of cargo, suggesting that the internal structure of the LNP is an important factor that affect the therapeutic effect. Further details can be found in the article by Fumika Kubota, Satrialdi, Yuta Takano, Masatoshi Maeki, Manabu Tokeshi, Hideyoshi Harashima, and Yuma Yamada ( e202200119 ).
A high‐efficiency computer‐aided diagnostic model of ovarian cancer was developed, integrating SHG imaging technology for non‐invasive imaging of living tissue and machine learning method based on radiomics and TPOT. This model can rapidly, non‐destructively, and accurately perform ovarian cancer diagnosis and has great potential in improving diagnostic efficacy and efficiency of medical pathologists. Further details can be found in the article by Guangxing Wang, Yang Sun, Youting Chen, Qiqi Gao, Dongqing Peng, Hongxin Lin, Zhenlin Zhan, Zhiyi Liu, and Shuangmu Zhuo ( e202000050 ).
Immunofluorescence image of Plasmodium berghei sporozoites (red) in HeLa cells 1.5 hours post infection. The parasitophorous vacuole membrane (PVM) that surrounds the parasites was stained with antibodies against the PVM‐resident protein UIS4 (grey). DNA was stained with DAPI (blue). Imaging was performed on a Leica SP8 confocal microscope. For further details, readers are referred to the article by Bindschedler et al. on p. e13271 of this issue.
A novel volumetric information fusion based on joint weighted evaluation and stationary wavelet transform is proposed. Threedimensional stationary wavelet transform was performed on multi-focus data to obtain wavelet coefficients. Differential evolution based on joint weighted evaluation was then employed to optimize the block size of division. Corresponding sub-coefficients of multi-focus data were fused with the proposed fusion rule. Finally, large volumetric and high-resolution photoacoustic imaging can be achieved by applying the inverse stationary wavelet transform. Further details can be found in the article by Xianlin Song, Sihang Li, Zhuangzhuang Wang, and| Xiongjun Cao ( e202200234 )
Images of bacterial cells stained with KK114 dye and visualized with STED microscopy. On the monitor: large field of view of B. subtilis cells, the KK114 ball‐and‐stick model and the schematics of the STED setup. Different space‐filling representations of the FtsZ protein are also shown. Further details can be found in the article by Massimiliano Lucidi, Radu Hristu, Lorenzo Nichele, George A. Stanciu, Denis E. Tranca, Alina Maria Holban, Paolo Visca, Stefan G. Stanciu, and Gabriella Cincotti ( e202000097 ).
Top: Illustration of how to obtain 3D embryo images from a locust egg using OCT B‐scans. The internal structures of the embryo can be clearly identified as it develops. Bottom: The real time observation of katatrepsis and twist of a lowland locust embryo on days 7‐8, as the embryo develops. The embryonic movements can be readily identified by tracking the positions of the embryo's eyes (E1 and E2). Further details can be found in the article by Ya Su, Liya Wei, Hao Tan, et al. ( e201960047 ).
A 3D printed stereotaxic head mount that enables high resolution imaging of the anterior chamber of the eye in alert and freely mobile mice is designed in this study. The system is placed non‐invasively using temporal mount bars and a snout mount, without breaking the skin or risking suffocation, while an endoscopic channel stabilizes the ocular probes. Further details can be found in the article by Bjorn Paulson, Sangwook Lee, Miyeon Jue, Kyungsung Lee, Sanghwa Lee, Guk Bae Kim, Youngjin Moon, Joo Yong Lee, Namkug Kim, and Jun Ki Kim ( e201960188 ).
