Journal of Biophotonics最新文献

Optical biosensors are emerging as a promising technique for the sensitive and accurate detection of cancer biomarkers, enabling significant advancements in the field of early diagnosis. This study elaborates on the latest developments in optical biosensors designed for detecting cancer biomarkers, highlighting their vital significance in early cancer diagnosis. When combined with targeted nanoparticles, the bio-fluids can help in the molecular stage diagnosis of cancer. This enhances the discrimination of disease from the normal subjects drastically. The optical sensor methods that are involved in the disease diagnosis and imaging of cancer taken for the present review are surface plasmon resonance, localized surface plasmon resonance, fluorescence resonance energy transfer, surface-enhanced Raman spectroscopy and colorimetric sensing. The article meticulously describes the specific biomarkers and analytes that optical biosensors target. Beyond elucidating the underlying principles and applications, this article furnishes an overview of recent breakthroughs and emerging trends in the field. This encompasses the evolution of innovative nanomaterials and nanostructures designed to augment sensitivity and the incorporation of microfluidics for facilitating point-of-care testing, thereby charting a course towards prospective advancements.

Ischemic stroke (IS) is characterized by the sudden interruption of blood supply to the brain, resulting in neurological impairments and even mortality. Photoacoustic computed tomography (PACT) integrates the high contrast of optical imaging and the penetration of ultrasound imaging, enabling non-invasive IS evaluation. However, the image reconstruction quality significantly affects the oxyhemoglobin saturation (sO₂) estimation. This study investigates a model-based with total variation minimized by augmented Lagrangian and alternating direction (MB-TVAL3) approach and compared it with the widely used back-projection (BP) and delay-and-sum (DAS) algorithms. Both simulations and in vivo experiments are conducted to validate the performance of the MB-TVAL3 algorithm, showing a higher sO₂ estimation accuracy and sensitivity in detecting infarct area compared to BP and DAS. The findings of this study emphasize the impact of acoustic inverse problem on the accuracy of sO₂ estimation and the proposed approach offers valuable support for IS evaluation and cerebrovascular diagnosis.

Postoperative corneal biomechanical evaluation is of great significance in clinical monitoring and management since corneal transplantation is one of the main methods to improve visual function. In this paper, we propose an OCE system based on a small ultrasound transducer to realize the in vivo detection of postoperative corneal elasticity in different directions. It was first validated and analyzed by different agar, and then the elasticity changes in normal cornea and post-transplant corneal implants and implant beds were further investigated. Compared with normal corneas, the shear wave velocity of the postoperative cornea decreased from 7.42 ± 1.71 m/s to 4.95 ± 0.35 m/s. Meanwhile, the shear wave velocity of the corneal implant bed was lower than that of the implanted sheet. Therefore, this study reports the first biomechanical measurement of corneal grafts based on the OCE technique, which might provide a potential tool for the postoperative evaluation of clinical patients.

Regular monitoring of blood oxygenation is important for disease prevention and treatment. Image photoplethysmography (IPPG) technology is a non-contact physiological parameter detection technology, which has been widely used in blood oxygenation detection. However, traditional imaging devices still have issues such as low detection accuracy, narrower receiving spectral range. In this paper, we proposed two improved detection methods based on the dual-wavelength measurement principle, that is, dual-band IPPG signal ratio method and dual-band IPPG signal AC/DC method. To verify the effectiveness of the two methods, we used different heartbeat period IPPG signals as sample data sets, and combined PLS and RF algorithms for model training, thus obtaining the best data processing method. The experimental results showed that the dual-band IPPG signal AC/DC method can effectively reduce the model training time. This method meets the strong demand for non-contact blood oxygen measurement and provides a new measurement idea.

Rapid and accurate identification of bacterial species is essential for the effective treatment of infectious diseases and suppression of antibiotic-resistant strains. The unique autofluorescence properties of bacterial cells are exploited for rapid and cost-effective identification that is suitable for point-of-care applications. Fluorescence spectroscopy is combined with machine learning to improve the diagnostic accuracy. Good training data for machine learning can be obtained to achieve the same diagnostic accuracy for bacterial species as when each wavelength is measured in detail over a broad spectral width. Experiments were performed testing 14 bacterial strains. The excitation-emission matrix was analyzed, and Bayesian optimization was used to identify the most effective combinations of wavelengths. The results showed that fluorescence spectra using three specific excitation light regions or excitation spectra using two broad fluorescence detection regions could be used as supervised data to realize diagnostic accuracy comparable to that obtained with more complex instruments.

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.

Evaluating the biomechanical properties of the lens and lens capsule is important for the clinical diagnosis and treatment of age-related cataracts and presbyopia. In this study, we developed an optical coherent elastography technique to assess the elasticity of the lens and lens capsule in the human eye. With age, the mean Young's modulus of the lens increased from 12.28 ± 0.87 kPa to 18.59 ± 1.45 kPa, and the lens capsule increased from 6.33 ± 0.36 kPa to 13.33 ± 0.74 kPa. The results showed that the Young's modulus of the lens capsule and lens increased with age, with the Young's modulus of the lens significantly higher than that of the lens capsule. This study reports the assessment of the elasticity of the human lens and lens capsule by the OCE technique, indicating that it may provide a potential clinical tool for advancing research on diseases affecting the lens.

Photobiomodulation (PBM) has been shown to be promising for the promotion of angiogenesis. The present study investigated the effects of PBM on vascularization in an animal model of peripheral artery disease. Wistar rats were divided into three groups. The control group received no procedures. The ischemia group was submitted to ligation of the femoral artery of the hindleg. The ischemia + PBM group was submitted to ligation of the femoral artery followed by PBM (660 and 808 nm, 100 mW, 4 J) over the site. Animals with ischemia treated with PBM exhibited comparable results to the control group with regards to the diameter of the α-SMA+ vessels, cross-sectional area of muscle fibers, percentage of collagen and serum concentration of IL-17A, as well as similarities in terms of vertical mobility, temperature of the hindleg, number of acts of grooming, and percentage of movement, indicating a condition like that of limbs unaffected by ischemia.