Journal of Biophotonics最新文献

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.

This study investigates the prognostic value of tumor-infiltrating lymphocytes (TILs) in luminal B breast cancer patients using multiphoton microscopy (MPM) and evaluates their association with 5-year disease-free survival (DFS). We obtained unlabeled MPM images from 213 patients, quantified the frequency of TILs, and assigned a TILs-score to each patient using ridge regression analysis. In addition, compared with single CLI-score model, the nomogram model, which integrated the TILs-score model with CLI-score model, further enhanced the predictive power for the luminal B subgroup. Specifically, the area under the curve (AUC) for 5-year DFS increased from 0.740 to 0.830 and hazard ratio (HR) increased from 5.31 to 7.24 in the training cohort; in the validation cohort, AUC increased from 0.716 to 0.822 and HR increased from 3.08 to 5.01. These findings suggest that the MPM-based TILs-score is a robust prognostic factor for luminal B breast cancer, potentially guiding more tailored treatment protocols.

Parkinson's disease (PD) is one of the most common neurodegenerative disorders, highlighting the urgent need for early, reliable biomarkers. Structural disorder at the subcellular level, particularly in nuclear components such as DNA/chromatin, offers a promising diagnostic target. In this study, we applied two mesoscopic physics-based optical techniques—partial wave spectroscopy (PWS) and inverse participation ratio (IPR)—to quantify nanoscale structural alterations in postmortem human brain tissues and nuclei. Both PWS and IPR revealed a significant increase in structural disorder and mass density fluctuations in DNA/chromatin of PD samples. These abnormalities are potentially linked to the pathological aggregation of alpha-synuclein in the substantia nigra, a hallmark of PD-related neurodegeneration. Complementary histological analyses supported the optical findings, validating the presence of disrupted microarchitecture. Our results establish PWS and IPR as sensitive optical/photonics tools for detecting early nanoscale changes in PD, offering a novel path toward improved diagnosis and understanding of disease progression.