This paper introduces an advanced dual-modality imaging platform by integrating a confocal laser scanning/imaging module with flat-fielding quantitative phase contrast microscopy (FF-QPCM). The platform enables phase/fluorescence dual-modality imaging of the same samples with high resolution and contrast. Using this platform, we observed that confocal fluorescence excitation causes minimal damage to cells, whereas wide-field fluorescence excitation results in significant damage, particularly mitochondrial fragmentation and notable alterations in phase values. Additionally, in situ quantitative phase imaging was conducted on live COS7 cells with a specific region irradiated by a confocal laser. The results demonstrated that 5-minute continuous confocal laser irradiation affects only COS7 cells with fluorescently labeled mitochondria, causing mitochondrial dysfunction throughout the cell. These findings suggest that integrating FF-QPCM with a confocal laser scanning/imaging module offers a highly efficient, sensitive, and information-rich tool for cell biology research, with broad application potential.

Despite the frequent failure of aortic valves and pediatric usage of pulmonary valves as a replacement, comparative studies on their full-field collagenous architecture and macroscale geometries are limited. We applied laser micrometry and quantitative polarized light imaging (QPLI), a novel technique for assessing collagen fiber organization, to porcine aortic (n = 8) and pulmonary (n = 8) valve leaflets to non-destructively compare thickness and anisotropy. We confirmed (1) light intensity and sample thickness are inversely related; and (2) aortic valve leaflets are thicker with decreased fiber organization when unloaded. To demonstrate the ability of QPLI to capture dynamic collagen fiber alignment, we imaged leaflets during equibiaxial loading. There was an increase in the aortic valve leaflet’s degree of alignment throughout loading, whereas the pulmonary valve leaflet exhibited relatively unchanged alignment. Understanding the full-field organization of a leaflet’s heterogeneous ECM and how it is altered by pathology can inform therapy development.

Blood vessels are an important part of the human circulatory system [1-4]. In clinical surgery, the common method for treating ruptured blood vessels is suturing, but this method can cause inflammatory reactions [5-6]. With the popularization of lasers, they have been widely used in the medical field. However, due to the poor absorption of laser energy by tissues, the tensile strength of tissues after joining is low. To further improve the tensile strength after laser joining, this study analyzed the law of the effect of pre-dressing-assisted laser on the tensile strength and thermal denaturation of vascular tissues after joining with different components and concentrations by designing experiments. The experimental results showed that the tensile strength of the joined tissues could reach 50.978 KPa, and the degree of thermal denaturation was only 0.025, which is of great significance for the study of laser-joined vascular tissues.

A document by Natalia A. Virts. Click on the document to view its contents.

Breast augmentations, commonly performed for aesthetic or medical reasons, often use silicone (PDMS) implants. Some patients develop complications like capsular contracture, where scar tissue forms around the implant. Previously, we used stimulated Raman scattering (SRS) microscopy to detect and quantify silicone in stained capsule tissue, finding a correlation between silicone amount and contracture severity. However, we suspected silicone loss during histological preparation, which includes multiple steps like formalin fixation and paraffin embedding. In this study, we assessed silicone loss by comparing adjacent tissue samples from the same capsule: one prepared conventionally and the other snap-frozen. SRS microscopy revealed that snap-frozen samples had roughly five times more silicone, indicating significant silicone loss during conventional preparation. Thus, measuring silicone in histologically prepared samples likely underestimates PDMS content.

Keratoconus and other corneal ectatic disorders involve the degradation of collagen fibers, which compromises the corneal biomechanical properties. UVA crosslinking has emerged as the primary treatment to slow down collagen degradation. This treatment is limited in both penetration depth and spatial precision, potentially leading to unwanted side effects. This work compares the changes in stiffness of corneas crosslinked with UVA irradiation and a near infrared femtosecond laser, using Brillouin microscopy. The stiffness of the crosslinked regions was mapped in terms of Brillouin frequency shift in three dimensions. UVA crosslinking showed an average increase in Brillouin shift of ~ 100 MHz. We demonstrate targeted spatial and axial corneal femtosecond crosslinking, with similar Brillouin shift values to UVA in crosslinked regions.

The image contrast and probing depth of optical methods applied to in vivo skin could be improved by reducing skin scattering using the optical clearing method. The aim of the present study was to quantify, from line-field confocal optical coherence tomography (LC-OCT) 3D images, the modifications of skin scattering properties in vivo during optical clearing. Nine mixtures of optical clearing agents were used in combination with physical and chemical permeation enhancers on human skin of three healthy volunteers. Scattering coefficient and anisotropy factor of the epidermis and the upper dermis were estimated from the 3D LC-OCT images of skin using an exponential decay model of the in-depth intensity profile. We were able to demonstrate a decrease in epidermal scattering (down to 33%)  related to optical clearing with the best results obtained by a mixture of Polyethylene Glycol, Oleic Acid and Propylene Glycol.

：Thymoma, a rare tumor from thymic epithelial cells, presents diagnostic challenges due to the subjective nature of traditional methods, leading to high false-negative rates and long diagnosis times. This study introduces a thymoma classification technique that integrates hyperspectral imaging with deep learning. We initially capture pathological slice images of thymoma using a hyperspectral camera and delineate regions of interest to extract spectral data. This data undergoes reflectance calibration and noise reduction. Subsequently, we transform the spectral data into two-dimensional images via the Gramian Angular Field (GAF) method. A variant residual network is then utilized to extract features and classify these images. Our results demonstrate that this model significantly enhances classification accuracy and efficiency, achieving an average accuracy of 95%. The method proves highly effective in automated thymoma diagnosis, optimizing data utilization and feature representation learning.

Gleason grading system is dependable for quantifying prostate cancer. This paper introduces a fast multiphoton microscopic imaging method via deep learning for automatic Gleason grading. Due to the contradiction between multiphoton microscopy (MPM) imaging speed and quality, a deep learning architecture (SwinIR) is used for image super-resolution to address this issue. The quality of low-resolution image is improved, which increased the acquisition speed from 7.55s per frame to 0.24s per frame. A classification network (Swin transformer) was introduced for automated Gleason grading. The classification accuracy and F1-score achieved by training on high-resolution images are respectively 90.9% and 90.9%. For training on super-resolution images, the classification accuracy and F1-score are respectively 89.9% and 89.9%. It shows super-resolution image can provide a comparable performance to high-resolution image. Our results suggested MPM joint image super-resolution and automatic classification methods holds the potential to be a real-time clinical diagnostic tool for prostate cancer diagnosis.

We conducted a clinical trial with 200 type 2 diabetes patients to evaluate mμSORS for non-invasive blood glucose measurement. Using Optical Coherence Tomography, we studied skin thickness and optical attenuation in 172 diabetic and 26 healthy subjects. Results showed thicker stratum corneum and stratum spinosum in diabetics. Epidermal thickness increased with age and BMI, decreased with skin brightness, and varied minimally with gender. Optical attenuation in stratum spinosum was lower in diabetics, decreased with increasing a*, and was minimally affected by gender and BMI but increased with age in the upper dermis. These findings support mμSORS for accurate non-invasive glucose monitoring.

Photobiomodulation (PBM) has emerged as a potentially effective therapeutic approach to modulate cellular functions. This study aimed to examine the impact of PBM on reactive oxygen species (ROS) and lipid peroxidation, and glutathione-related antioxidant defense systems in rabbit eye tissues. A polychromatic light source with an intensity of 2.6 J/cm 2/min was used for PBM treatment in New Zealand White rabbits for 12 minutes. The PBM group (n=8) received treatments every two days for a total of twelve sessions, while the control group (n=8) did not undergo any PBM light exposure during the same period. The application of PBM significantly elevated ROS-mediated glutathione levels, along with increased activities of glutathione peroxidase and reductase, particularly in corneal tissue ( p ≤ 0.05). In conclusion, these findings could enhance understanding of PBM’s therapeutic potential for eye health and lead to new strategies for preventing or treating ocular diseases caused by oxidative stress.

Non-invasive, rapid and robust diagnostic techniques for clinical screening of tumors located in arbitrary areas of the human body are in demand. To address this challenge, we analyzed the feasibility of vessel mapping by means of time-lapse digital microscopy for assessing vascular patterns within malignant and benign tumors. The proposed hardware and software were approved in a clinical study involving 30 patients with tumors located in legs, torso, arms, and head. High-contrast and detailed vessel maps within both benign and malignant tumors were obtained. We demonstrated that capillary maps are consistent and can be interpreted using well-established dermoscopic criteria for the vascular morphology. Vessel mapping provides valuable details, which may not be available in dermoscopic images and can aid in determining whether a tumor is benign or malignant. We believe that the proposed approach may become a valuable tool in the preliminary cancer diagnosis and is suitable for large-scale screening.

This study presents a portable spectroscopic system compatible with ambient light to assess hepatic steatosis (HS) and macrovesicular steatosis (MaS) in human liver specimens. Traditional assessment methods for MaS are limited, prompting the need for non-invasive alternatives. The study utilized a two-stage approach on thawed snap-frozen liver specimens. Biochemical validation compared fat content from Raman and reflectance intensities with triglyceride (TG) quantifications, while histopathological validation contrasted Raman-derived fat content with pathologist evaluations and an algorithm. Analysis of 16 specimens showed a positive correlation between spectroscopic data and TG quantifications. The Raman system differentiated various degrees of global HS and MaS in an additional 66 specimens. A dual-variable prediction algorithm classified significant discrepancies (≥10%) between algorithm-estimated global HS and pathologist-estimated MaS. This study demonstrates the viability of a portable spectroscopic system for non-invasive HS and MaS assessment to enhance real-time donor liver assessments during recovery to improve transplantation outcomes.

The aim was to investigate the effects of different volumes of strength training (ST) in association with photobiomodulation (PBMt) in mice fed a high-fat diet (HFD) on insulin resistance (IR). Male Swiss albino mice were fed HFD and performed high- or low-volume (one-third) ST (3 days/week), associated with PBMt (660 nm + 850 nm; ~42 J delivered) or not (lights off). ST improved IR, lowered visceral adiposity and circulating cytokines, and increased skeletal muscle hypertrophy and mitochondrial activity. The smaller volume of ST did not interfere with the improvement in IR, mitochondrial activity, or inflammatory profile, but exerted a smaller effect on visceral adiposity and skeletal muscle hypertrophy. Association with PBMt further improved IR, regardless of ST volume, although it did not affect adiposity, mitochondrial activity, and the inflammatory profile. Interestingly, PBMt positively affected quadriceps, but attenuated gluteus maximus hypertrophy. The association with PBMt induced greater improvement than ST alone.

Fundus photography (FP) is a crucial technique for diagnosing the progression of ocular and systemic diseases in clinical studies, with wide applications in early clinical screening and diagnosis. However, due to the non-uniform illumination and imbalanced intensity caused by various reasons, the quality of fundus images is often severely weakened, brings challenges for automated screening, analysis and diagnosis of diseases. To resolve this problem, we developed strongly constrained generative adversarial networks (SCGAN). The results demonstrate that the quality of various datasets were more significantly enhanced based on SCGAN, simultaneously more effectively retaining tissue and vascular information under various experimental conditions . Furthermore, the clinical effectiveness and robustness of this model was validated by showing its improved ability in vascular segmentation as well as disease diagnosis. Our study provides a new comprehensive approach for FP and also possesses the potential capacity to advance artificial intelligence-assisted ophthalmic examination.

This study explores a combined strategy of Raman and reflectance spectroscopy for quantifying liver fat content and fat droplet size, crucial in assessing donor livers. By using Monte Carlo simulations and experimental setups with oil-in-water phantoms, our findings indicate that Raman scattering can solely differentiate between varying fat contents, while reflectance intensity is influenced by both fat content and oil droplet size, with a more pronounced sensitivity to fat droplet size. This study demonstrates the efficacy of combined Raman and reflectance spectroscopy in assessing liver steatosis and fat droplet size, potentially aiding in assessing donor livers for transplantation.

Nailfold capillaroscopy is an important means of monitoring human health. Panoramic nailfold images improve the efficiency and accuracy of examinations. However, the acquisition of panoramic nailfold images is seldom studied and the problem manifests of few matching feature points when image stitching is used for such images. Therefore, this paper presents a method for panoramic nailfold image stitching based on vascular contour enhancement, which first solves the problem of few matching feature points by pre-processing the image with contrast-constrained adaptive histogram equalization (CLAHE), bilateral filtering (BF), and sharpening algorithms. The panoramic images of the nailfold blood vessels are then successfully stitched using the fast robust feature (SURF), fast library of approximate nearest neighbors (FLANN) and random sample agreement (RANSAC) algorithms. The experimental results show that the panoramic image stitched by this paper’s algorithm has a field of view width of 7.43 mm, which improves the efficiency and accuracy of diagnosis.

Pollution from toxic spores has caused us a lot of problems, because spores are extremely resistant and can survive most disinfectants. Therefore, the detection of spore response to disinfectant is of great significance for the development of effective decontamination strategies. In this work, we investigated the effect of 0.5% sodium hypochlorite on the molecular and morphological properties of single spores of Bacillus subtilis using single-cell techniques. Laser tweezers Raman spectroscopy showed that sodium hypochlorite resulted in Ca 2+-dipicolinic acid release and nucleic acid denaturation. Atomic force microscopy showed that the surface of treated spores changed from rough to smooth, protein shells were degraded at 10 min, and the permeability barrier was destroyed at 15 min. The spore volume decreased gradually over time. Live-cell imaging showed that the germination and growth rates decreased with increasing treatment time. These results provide new insight into the response of spores to sodium hypochlorite.