Journal of Biophotonics最新文献

Metastasis is the leading cause of death in tumor patients, with circulating tumor cells (CTCs) serving as key biomarkers for tumor progression, metastasis, and recurrence. CTC quantity is closely linked to tumor dynamics, which are influenced by biological rhythms. Studying CTC distribution under various physiological conditions provides insights into metastasis mechanisms. However, due to the low abundance of CTCs, detection accuracy is limited, especially with small blood samples, making continuous data collection challenging. To address this, we developed a dual-channel miniaturized in vivo fluorescence microscopy system for real-time monitoring of CTCs in experimental animals. This system, which can be fixed to the head or back, enables dynamic, quantitative analysis of CTCs in the circulatory system. It offers a valuable tool for investigating tumor metastasis rhythms, drug evaluation, and prognostic assessment in freely moving animals, advancing research in metastasis mechanisms and cancer treatment.

A visible–near infrared (VIS–NIR) projected multispectral imaging (Proj-MSI) system consisting of an MSI subsystem and a compact projector for intraoperative breast tumor margin assessment was developed. MSI with an average spectral resolution of 24 nm was realized through sequential illumination of 26 sets of VIS–NIR light-emitting diodes and synchronized single NIR-sensitive camera image capture. Rapid (~1 min) tumor margin delineation revealed significantly (p < 0.01, Student's t-test) reduced reflectivity associated with breast tumor. Speeded-up robust features algorithm-based field of view calibration allowed the MSI identified tumor margins to be projected directly onto the breast-conserving surgery (BCS) surgical cavity with a projection error of < 1 mm. Besides, the projected tumor margin boundaries were outlined using Indian ink to simulate breast tumor removal, demonstrating the potential of the Proj-MSI system developed for intraoperative tumor margin assessment during BCS.

Increasing evidence has underscored the pivotal role of red photobiomodulation (R-PBM) in analgesic and anti-inflammatory processes; nonetheless, research concerning the effects of pulsed wave on primary dysmenorrhea (PD) remains sparse. This study found that pulsed R-PBM significantly diminished pain responses and levels of PGF_2α/PGE₂, mitigated uterine swelling, augmented antioxidant capacity, and lowered MDA concentrations, which outperformed continuous wave at the same average irradiance. Furthermore, PW treatment substantially reduced ROS levels and enhanced cell viability in PGF_2α induced HUSM cells. NOS levels, especially iNOS, were markedly diminished in the uteri of PD mice, accompanied by significant alterations in inflammation-related genes (Jun, Fos, IL1rn, IL17b) and protein levels, along with pronounced downregulation of calcium ion concentrations after pulsed R-PBM intervention. These findings indicated that pulsed R-PBM may mitigate pain by modulating ROS and NO/NOS, mediated oxidative stress and inflammatory responses. Consequently, pulsed R-PBM emerges as a promising therapeutic strategy for PD.

Androgenetic alopecia (AGA) causes balding in approximately 50% of adults. One primary cause of AGA is synthesis of dihydrotestosterone from testosterone by 5-α reductase. Systemic pharmaceutical interventions have potentially serious side effects, necessitating development of localized interventions. One such approach is administration of red light via low level light therapy (LLLT), which has promising clinical data. However, the LLLT mechanism of action remains unclear. We investigated the ability of LLLT to stimulate nitric oxide (NO) and the role of NO in inhibition of DHT synthesis. Our results show that red and red-orange light induce NO release in a cell-free platform. In A549 and HEK293T cells, we demonstrate 620 and 660 nm LED-emitted light stimulates the production of NO, reactive oxygen species (ROS), and decreases DHT synthesis. These results provide a plausible mechanism of action for LLLT employing LED-emitted red and red-orange wavelengths of light to treat AGA.

Blood vessels are an important part of the human circulatory system. In clinical surgery, the common method for treating ruptured blood vessels is suturing, but this method can cause inflammatory reactions. 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.

Alzheimer's disease (AD) is a public health concern, for which an early diagnosis is essential. Biomass-derived carbon fibres with surface-decorated silver nanoparticles (Ag@CFs) have been utilized as surface enhanced raman spectroscopy (SERS) sensor platform for the detection of the amyloid beta Aβ (25–35) for the pre-diagnosis of Alzheimer's disease. Structural and morphological characterizations confirmed the distribution of plasmonic silver nanoparticles over the surface of carbon fibres. The SERS sensor performance of Ag@CFs was evaluated using rhodamine 6G, which showed an enhancement of the order of 10⁶ which proved the effectiveness of the developed SERS sensor towards trace level detection of analyte. A range of amyloid beta concentrations, from 100uM to 10pM, have been analyzed as a proof-of concept for this study, showcasing the efficacy of the Ag@CFs based SERS sensor to detect trace level concentrations of amyloid beta, even as low as 10 pM. This investigation is a promising development in the field of AD diagnostics since it may turn out to be a non-invasive, economical and early diagnostic tool.

Prenatal alcohol exposure (PAE) is a major contributor to fetal alcohol spectrum disorder (FASD), resulting in neurodevelopmental abnormalities. This study utilizes photoacoustic tomography (PAT) to investigate the effects of PAE on fetal brain vasculature in mice. PAT imaging was conducted from embryonic Day 10 (E10) to Day 20 (E20), aimed to compare two alcohol-exposed groups with a control group. Key vascular parameters, including blood vessel diameter and density, and oxygen saturation (sO₂), were analyzed. Results show significant reductions in vessel size and density, as well as reduced sO₂ levels, in alcohol-exposed groups, especially from E14 onward, compared to controls. These findings underscore the vulnerability of the fetal brain to alcohol exposure during early development and highlight the potential of PAT as a valuable tool for investigating FASD-related vascular changes.

Employing longer wavelengths in optical microscopic imaging is recognized for its advantage in deep penetration. However, the 1550 nm spectrum band is often overlooked due to water's high absorption coefficient. This study investigates the feasibility of 1550 nm center wavelength-based optical coherence tomography (OCT) for imaging the cerebral vasculature and blood flow in the mouse brain cortex. In comparison to a commercial 1310 nm OCT system, the 1550 nm OCT system exhibits greater attenuation in deeper regions while yielding similar results in blood flow imaging across the entire cortex layers. Given the widespread use of the 1550 nm wavelength band in the communication industry, the associated costs for light sources, linear cameras, and optic components are relatively lower than those of the 1310 and 1700 nm bands. Therefore, the 1550 nm band OCT could be a favorable choice for imaging deep brain cerebral hemodynamics.