Journal of Biophotonics最新文献

Macrophages (MΦs) are integral cellular components responsible for immune response and tissue homeostasis. Evaluation of their pro-inflammatory (M1) and anti-inflammatory (M2) polarization states, along with their metabolic profiles, typically conducted via flow cytometry, is crucial for assessing the immune status of an organism. Traditional flow cytometry relies on extrinsic fluorescent labels, which may interfere with cellular function. Here, using multispectral flow cytometry, we demonstrate how the autofluorescence profiles of human monocyte-derived macrophages change under M1/M2 polarization, hypoxia and starvation stress factors, and interaction with low-density lipoproteins as an atherosclerosis model. Extending these findings to clinical samples, we demonstrated that leukocyte AF profiles could distinguish atherosclerosis patients from healthy controls with a ROC-AUC of 0.84 ± 0.09, advanced predictive models. These findings highlight AF as a sensitive, non-invasive tool for assessing macrophage activation and metabolic states, with potential applications in atherosclerosis diagnostics and immune cell phenotyping.

Accurate classification of gastric cancer differentiation is crucial for prognosis and treatment decisions. In this study, we propose a lightweight deep learning model—Improved Deep Residual Network (IDRN)—combined with hyperspectral imaging (HSI) to achieve precise identification of gastric cancer tissues. The model incorporates spectral preprocessing, dimensionality reduction, and a residual CNN with attention mechanisms to enhance feature extraction while maintaining efficiency. Comparative experiments with SVM, ResNet50, and ViT models show that IDRN achieves superior performance, particularly in identifying poorly differentiated tissues. Our approach provides a promising tool for computer-aided diagnosis and offers potential for clinical translation.

We report the results of an experimental study of the movement and trapping of Gram-negative Escherichia coli (E. coli) bacteria in broth suspensions, under photovoltaic fields generated by an optical Bessel beam illumination of the surface of a lithium niobate crystal (photovoltaic tweezers). The study was performed using a phase-sensitive transmission microscope. Experiments showed that the direct electrical interactions are suppressed due to the screening of the negative charge of bacteria by Na⁺ counterions present in broth media because of the dissociation of NaCl in the water. The immobilization and trapping of ~95% of bacteria in the area of the recorded hologram (~2 mm²) require ~40 min. The velocity map of bacteria movement in the photovoltaic lattice is constructed. The formation and destruction of bacterial chains are also observed and discussed. The proposed method is a non-invasive microscopy technique with inserted chip-scale photovoltaic tweezers.

Optical coherence tomography (OCT) provides high-resolution, non-invasive visualization of biological tissues, enabling structural imaging and the visualization of microvascular networks. However, tissue scattering remains a significant limitation for achieving deeper imaging penetration and improved image quality. Optical clearing agents help minimize this scattering, enhancing OCT imaging capabilities. This study investigates the optical clearing effects of tartrazine, a commonly used food dye, to improve OCT and OCT angiography imaging. In ex vivo chicken breast, tartrazine solution demonstrated enhanced penetration depth and reversible optical clearing. In vivo mouse skin was evaluated using parameters such as extinction coefficient, signal-to-noise ratio, contrast-to-noise ratio, and vessel density. The results revealed substantial reductions in light scattering, improved imaging penetration, and enhanced visualization of vascular networks after applying tartrazine solution.

Photonics/light localization techniques are essential in understanding the structural changes in biological cells/tissues at the nano- to sub-micron scale. It is now known that structural alterations begin at the nanoscale, marking the onset of cancer progression. This photonics study examines the molecular-specific nano-structural alterations of chronic alcoholism and probiotic effects on colon cancer using a mouse model of colon cancer. We assessed alcohol-treated and azoxymethane (AOM) with dextran sulfate sodium (DSS)-induced colitis models, including ethanol (EtOH) and probiotic (L.casei) treatments separately and together. The confocal images were analyzed using the mesoscopic physics-based Inverse Participation Ratio (IPR) technique to quantify structural alterations at nano- to submicron scales. Significant enhancement of cancer progression was observed in the EtOH-treated group, and probiotic treatment with EtOH showed substantial reversal of these changes in colon cancer, underscoring the potential of the IPR technique in detecting and monitoring cancer progression.

Alzheimer's disease (AD) involves retinal changes that may serve as biomarkers, given the retina's connection to the brain via the visual cortex. Variability in AD research arises from methodological differences, patient diversity, and evolving hypotheses. This study explores AD progression and complexity using synchronous and emission map fluorescence spectroscopy of retinas from rats administered aluminum chloride for 3, 6, 9, and 12 weeks. Elevated retinal amyloid-beta (Aβ-40 and Aβ-42) levels suggest similar pathological changes as in the brain. In synchronous spectra, excessive or insufficient levels of structural proteins can enhance retinal dysfunction or disease, while emission map spectra revealed enhanced photosensitivity due to increased porphyrins over time (AD-6 to AD-12 weeks).

This study explores the use of hyperspectral imaging (HSI) to distinguish granulomatous mastitis (GM) from normal breast tissue in core-needle biopsy specimens. High-resolution spectral data were captured from paraffin-embedded sections across the 400–1000 nm range. Following preprocessing, normalization, and principal component analysis, one-way analysis of variance revealed ten wavelengths with the greatest diagnostic power. Notably, hemoglobin absorption peaks and lipid–collagen signatures provided the strongest spectral discrimination between GM and healthy tissue. These results underscore HSI's promise as a rapid, real-time adjunct for preoperative and intraoperative evaluation of breast lesions.