Journal of biophotonics最新文献

Liver malignancies, particularly hepatocellular carcinoma (HCC), pose a formidable global health challenge. Conventional diagnostic techniques frequently fall short in precision, especially at advanced HCC stages. In response, we have developed a novel diagnostic strategy that integrates hyperspectral imaging with deep learning. This innovative approach captures detailed spectral data from tissue samples, pinpointing subtle cellular differences that elude traditional methods. A sophisticated deep convolutional neural network processes this data, effectively distinguishing high-grade liver cancer from cirrhosis with an accuracy of 89.45%, a sensitivity of 90.29%, and a specificity of 88.64%. For HCC differentiation specifically, it achieves an impressive accuracy of 93.73%, sensitivity of 92.53%, and specificity of 90.07%. Our results underscore the potential of this technique as a precise, rapid, and non-invasive diagnostic tool that surpasses existing clinical methods in staging liver cancer and differentiating cirrhosis.

The work is devoted to the study of the physiological variability of the microcirculatory-tissue system (MTS) parameters under normal conditions and during functional tests. The results were obtained in vivo using multimodal wearable analyzers implementing methods of laser Doppler flowmetry and fluorescence spectroscopy. Comprehensive data analysis and calculation of the coefficients of variation of the MTS parameters of the human body for various topographic and anatomical areas of the skin were carried out. The obtained results showed higher values of the coefficient of variation of MTS parameters in the area of the toes and wrists, while the fingers and forehead skin showed lower levers of variation. In all areas of the study, reproducibility of the parameters obtained for the right and left areas of the study is observed.

Diabetes mellitus (DM), a chronic metabolic disorder that adversely affects the blood-brain barrier (BBB) and microglial function in the central nervous system (CNS), contributing to neuronal damage and neurodegenerative diseases. However, the underlying molecular mechanisms linking diabetes to BBB dysfunction and microglial dysregulation remain poorly understood. Here, we assessed the impacts of diabetes on BBB and microglial reactivity and investigated its mechanisms. We found diabetes severely disrupted the BBB integrity and microglial response to vascular injury. We also revealed a potential relationship between BBB disruption and impaired microglial function, whereby increasing BBB permeability led to a downregulation of microglial P2RY12 expression, thereby impairing microglial protection against cerebrovascular injury. Understanding these mechanisms may contribute to the developing of therapeutic strategies for diabetes-related neurological complications.

Skin homeostasis is strongly dependent on its hydration levels, making skin water content measurement vital across various fields, including medicine, cosmetology, and sports science. Noninvasive diagnostic techniques are particularly relevant for clinical applications due to their minimal risk of side effects. A range of optical methods have been developed for this purpose, each with unique physical principles, advantages, and limitations. This review provides an in-depth examination of optical techniques such as diffuse reflectance spectroscopy, optoacoustic spectroscopy, optoacoustic tomography, hyperspectral imaging, and Raman spectroscopy. We explore their efficacy in noninvasive monitoring of skin hydration and edema, which is characterized by an increase in interstitial fluid. By comparing the parameters, sensitivity, and clinical applications of these techniques, this review offers a comprehensive understanding of their potential to enhance diagnostic precision and improve patient care.

Diffuse optical tomography (DOT) enables the in vivo quantification of tissue chromophores, specifically the discernment of oxy- and deoxy-hemoglobin (HbO and HbR, correspondingly). This specific criterion is useful in detecting and predicting early-stage neoadjuvant breast cancer treatment response. To address the issues of the limited channels in the fiber-dependent breast DOT system and limited signal-to-noise ratio in the camera-dependent systems, we hereby present a camera-based lock-in detection scheme to achieve dynamic DOT with improved SNR, which adopted orthogonal frequency division multiplexing technology. The evaluation of the system performance was conducted on tissue phantoms and neoplastic rats, and the results show that this system boasts the capability of executing parallel measurement utilizing a camera detector, enabling the achievement of highly sensitive, and dynamic tomography for breast screening applications.

Neuroinflammation plays a key role in the development of neurodegenerative diseases, with microglia regulating this process through pro-inflammatory M1 and anti-inflammatory M2 phenotypes. Studies have shown that human umbilical cord mesenchymal stem cells (hUCMSCs) modulate neuroinflammation by secreting anti-inflammatory cytokines. Photobiomodulation (PBM), a non-invasive therapy, has demonstrated significant potential in alleviating neuroinflammation. This study examines the combined effects of PBM and hUCMSCs in an in vitro microglial inflammation model and an LPS-induced mouse model. The results show that PBM-pretreated hUCMSCs promoted M2 polarization and improved cognitive function in mice by downregulating the Notch signaling pathway, suggesting a promising new approach for treating neurodegenerative diseases.

Three-photon fluorescence (3PF) microscopy encounters significant challenges in biological research and clinical applications, primarily due to the limited availability of high-performance probes. We took a shortcut by exploring the excellent 3PF property of berberine hydrochloride (BH), a clinically utilized drug derived from the traditional Chinese medicine, Coptis. Capitalizing on its renal metabolism characteristics, we employed BH for in vivo 3PF microscopic imaging of the mouse kidney. This approach enabled high-resolution structural observation of renal tubules and facilitated the diagnosis of drug-induced acute kidney injury (AKI) based on renal tubule morphology. The analytical capabilities of 3PF microscopy for renal physiology and pathological diagnosis suggest its potential for future clinical applications.

In this study, the parameters of blood microcirculation and microrheology were measured using the methods of laser aggregometry and optical tweezers in vitro, as well as the method of digital capillaroscopy in vivo. It was shown that in patients suffering from type 2 diabetes mellitus, an increase in the number of RBC aggregates passing through the narrow capillaries leads to a significant decrease in the velocity of the capillary blood flow, which can be explained by the increased viscosity of the whole blood and decreased deformability of RBCs. Also, for the group of patients, a statistically significant increase in the rate of RBC aggregation and the hydrodynamic strength of aggregates, RBC aggregation and disaggregation forces were observed compared to the control group. We have demonstrated the possibility of using these methods to assess changes in microrheological and microcirculatory parameters of the blood.

The cornea is a transparent lens at the forefront of the eye, serving as a structural barrier that protects the eye and provides the majority of the eye's refractive power. In this study, we utilized the postnatal mouse eye to characterize corneal structure and biomechanics. Between postnatal day (PN) 6 and PN24, we observed that elastic wave speeds are highest at PN6, gradually decrease through PN24, and then start to rise in adulthood (6 months). We found that corneal thickness is uncoupled from elastic wave speed and that the content and organization of the cornea primarily influence its mechanical properties. To the best of our knowledge, this work is the first detailed assessment of the postnatal mouse cornea's structure and biomechanics and warrants further investigation into the dynamic properties of the postnatal eye.

This study explored the effects of 1267 nm laser irradiation on changes in blood flow parameters and activation of the regulatory mechanisms of the microcirculatory bed (MCB). Using laser Doppler flowmetry (LDF) technique and time-frequency analysis of perfusion signals, changes in the MCB of 16 healthy volunteers, targeting the distal phalanx of the third finger with 1267 nm laser irradiation were evaluated. Results indicated no significant differences in perfusion between control and target measurements, likely due to blood flow redistribution caused by vessel dilation/constriction. However, differences in oscillation amplitudes in endothelial and myogenic ranges were observed, suggesting microcirculation self-regulation. Detailed analysis revealed characteristic peaks in the endothelial range during and after irradiation, indicating endothelial mediator release. It is assumed that the identified effects may be related to the singlet oxygen generated by 1267 nm laser irradiation, which directly affects the MCB, manifesting as endothelium-dependent vascular activity.