Dysfunction of the lymphatic system plays a role in many disease processes, including lymphedema, hypertension, microbial infections and cancer. Expanding our knowledge of lymphatic system function can lead to a better understanding of these disease processes and improve treatment options. Here, the first measurements to characterize lymphatic vessel function in multiple segments were made in a living animal to begin to unravel how the lymphatic system is coordinated in normal and disease settings.

An imaging system for in vivo continuous monitoring of lymph vessels (LVs) and quantification of lymphatic function was developed. High frame rate bright-field videos of LVs were processed to automatically detect vessel diameter and flow velocity. System performance was tested on in vitro test samples and on a rat model of intestinal lymphadenectomy. Reduced LV contraction and flow rate were detected after surgical lymphadenectomy of the rat mesentery.

This study employs optical coherence tomography lymphangiography to image conjunctival lymphatics in porcine eyes ex vivo. The vessel segmentation, using the optical transparency of lymphatic and blood vessels, presents the ready visualization of vessel networks and indicates the varying spatial distribution of patent lymphatics. Such visualization of the conjunctival vessels provides a valuable reference on vessel morphology for subsequent in vivo label-free imaging studies of lymphatics. OCT lymphangiography imaging of conjunctival vessels from the surface to 350 μm deep.

Lymphedema of limbs is caused by obstruction of main lymphatic channels with subsequent accumulation of excess tissue fluid (lymph) in tissue spaces. It is treated by manual, mechanical pneumatic and bandage compression of swollen tissues. Evaluation of results is based on measurement of girth and volume of the limb. However, these methods do not give insight into how does edema fluid move during external compression. The indocyanine green lymphography enables live observation of fluid flow and sites of its relocation where absorption takes place. Imaging and estimation of local fluorescence level provide information of the efficacy of the applied compression method. Decreasing level of fluorescence is seen on consecutive pictures.

The lymphatic system in human tissues regulates the physico-chemical environment of cells by maintaining hydration, ions, nutritional and regulatory substances levels, draining away the metabolic products, senescent and damaged cell debris, and nonself antigens penetrating body as bacteria and viruses. Intercellular space is connected to a network of lymphatic vessels starting from capillaries and ending up as a 5 mm diameter wide thoracic duct merging with jugular-subclavian vein. All segments contract spontaneously rhythmically depending on how much lymph fluid fills them up. How does the lymphatic network look like in human limbs? Lymphoscintigram depicts main lower limb vessels between most distant tissues and the inguinal lymph nodes acting as a biological filters. Imaging lymphatics in human normal and lymphedema limbs—usefulness of various modalities for evaluation of lymph and edema fluid flow pathways and dynamics.

A lymphatic drug delivery system (LDDS) allows drugs to be injected into upstream lymph nodes (LNs) and to deliver drugs to downstream LNs via the lymphatic vessels. Here, we evaluated drug deliverability during the development of LDDS in MXH10/Mo-lpr/lpr mice with swollen LNs up to 10 mm in diameter. The distribution of fluorescein isothiocyanate-labeled tomato lectin into the downstream LN was dependent on the injection rates into the upstream LN.

It is a crucial physiological role of blood-brain barrier to protect the central nervous system against pathogens and toxic substances. However, this protective mechanism limits 98% of the beneficial drugs delivery as well. Our results contribute to a better understanding of the cerebrovascular effects of photodynamic treatment (PDT) and shed light on mechanisms, underlying brain clearing after PDT-related opening of blood-brain barrier, including clearance from nanoparticles as drug carriers.

Monte Carlo-simulated scattering map for photons at a wavelength of 980 nm propagating inside the human head model. Most scattering takes place in the skull layer. However, a significant amount of photons travels further through the areas where cerebrospinal fluid (CSF) flows. Our experiments demonstrate that using 980 nm in combination with 830 and 660 nm or 740 nm allows the simultaneous sensing of dynamic variations in water volume and haemodynamics in the human brain cortex. Observed fluctuations are assumed to be correlated with the dynamics of glymphatic circulation.

Age-related involution of the thymus gland is a major cause of immune suppression in elderly individuals. Photobiomodulation using near-infrared, red, blue or green light can improve the thymus gland function by increasing melatonin or by stimulating bone marrow stem cells and T-cell precursors.

Lymphatic malformations are complex vascular lesions composed of abnormal lymph vessels that can result in significant esthetic and physical impairment due to relentless growth. Here, we review the capability and limitations of current imaging technologies (e.g., ultrasonography and magnetic resonance imaging) to diagnose lymphatic malformations, and discuss perspectives to overcome existing challenges using new and emerging methods of vascular imaging and characterization such as the integration of photoacoustics, nanotechnology, and optical clearing for the advanced diagnosis and therapy (theranostics) of lymphatic malformations.

Podoplanin-labelled lymphatic malformation cysts. Note the variability in immunolabelling of podoplanin in the large cyst (#) when compared to strongly stained smaller lymphatic vessels (*) and negatively stained blood vessels (arrow).

Wide-field phase delay of mouse brain slice obtained by quantitative phase imaging in different wavelength and various pinhole size, from which it retrieves power spectrum in corpus callosum, scattering coefficient (μ_s) and anisotropy (g).

Gold/silver/gold nanostructured sensors based on commercial Blu-ray optical discs as substrates and with integrated microfluidics have been designed and optimized. Ultrasmooth and chemically stable trilayer nanoslit-based nanostructures were obtained following a simple and reproducible fabrication process. The direct and label-free detection of C-reactive protein (CRP) biomarker in undiluted urine was achieved with a LOD in the pM order.

Cervical cancer is the leading cause of death in women; it has no symptoms until the cancer stage. Hence, early diagnosis becomes extremely crucial. The environment of a natural fluorophore is probed through fluorescence lifetime and is useful in monitoring the development of cancer. Detection of abnormal region is enhanced by application of principal component analysis on FLIM images.

Rapid membrane damage of optically trapped red blood cells (RBCs) was observed presumably due to temperature gradient-induced electropermeabilization effect. When RBCs from type II diabetic patients were studied, a noticeable change in the damage rate compared to normal RBCs was seen suggesting a novel optical diagnosis method for the disease.

Early cataract formation is foretold by comparing scattering radial profiles light pattern distributions reflected upon the retina at 2 different wavelengths. The computational model developed presents wavelength-dependent scattering distributions with angular crossovers in them. We obtained that the crossover angular point is inversely proportional to the size of the particle distributions associated with the nucleation precursor of eye cataracts.

We propose that the quantitative photoacoustic spectroscopy of pulsatile blood flow can be a potential tool for probing hemodynamics and oxygen transport. Red blood cell aggregation during the pulsatile blood flow simultaneously affects the absorber size and the oxygen saturation (and, in turn, the absorption coefficient), so that the increasing slope of photoacoustic power as a function of wavelength for aggregation is steeper than that for nonaggregation.

The surface of a c− cut ferroelectric crystal at room temperature is characterized by screening surface charges, able to compensate the charge due to the spontaneous polarization. Here, we use holographic TIR microscopy show that cell adhesion is significantly different between the positive and negative face of a crystal of lithium niobate.

Light driven enhancement of fluorescence of Evans Blue dye complexes with blood plasma proteins was detected. It was observed both in vitro and in vivo. The possible background of the effect concerns the photochemical cis-trans isomerization of the dye molecules. We applied the effect for intravital molecular tagging velocimetry of the blood flow in a living animal circulating system that was performed for the first time..

Accumulation of advanced glycation end-products (AGEs) within bone matrix is thought to adversely affect fracture resistance. Yet, there is no non-destructive method to assess effects of AGEs on collagen I structure. Herein, we demonstrate the use of Raman spectroscopy to detect glycation-mediated changes in human bone ex vivo and highlight the effects of data collection and processing on probing spectral changes. Amide I sub-peak ratios are sensitive to AGE accumulation.

Ocular tissues have a complex collagen architecture, with fibers exhibiting 3D orientation, with both and orientations. Imaging techniques traditionally applied to the study of ocular tissues only quantify in-plane (IP) fiber orientation, providing little information on out-of-plane (OP) fiber orientation. 3dPLM, a technique based on polarized light microscopy, was developed to quantify both IP and OP fiber orientations of ocular tissues.

We developed a novel optical fiber sensor to detect DNA of Leptospira bacteria that causes Leptospirosis, a deadly disease typically spread by rodents. The challenge in the disease early detection is its symptoms are similar to flu. Significant sensitivity improvement in femtomolar concentrations is achieved by tapering (shrinking) and functionalizing the fiber toward the bacteria DNA. The sensor response is unique and highly potential for the disease early detection kit.

The left-hand side panel shows individual phase contrast images in isotropic differential phase contrast (iDPC) dataset with corresponding gradient amplitude mask on top-right side. White arrows denote phase gradient direction of each phase contrast image. The figure in right-hand side is quantitative phase image of alive human adipose-derived stem cells reconstructed using iDPC dataset.

A portable and low-cost smartphone octochannel spectrometer (SOS) that enables simultaneous detection of optical spectra of 8 samples. In a clinical validation using 180 patient samples, the SOS achieved a 100% accuracy compared to a clinical instrument. The SOS costs less than $20 and is self-illuminated. It is an ideal mobile health tool to bring diagnostics requiring spectrophotometry from central laboratory to patient side.

In this study, we used terahertz (THz) imaging to investigate the characteristics and distributions of different bacterial colonies and mixed bacterial samples. Single bacterial colonies of 4 bacterial species were directly distinguished as a result of their different THz absorption. In addition, same bacteria in different living states were successfully distinguished based on their different hydration levels and structural characteristics, demonstrating the potential of THz imaging for the label-free assessment of bacterial viability.

Autofluorescence-based protein fingerprinting for separation, visualization, differentiation and identification of proteins on Sodium Dodecyl Sulfate-Tris(2-carboxyethyl)phosphine (SDS-TCEP) polyacrylamide gel electrophoresis (PAGE). The technique gives quick information regarding protein's molecular weight, isoelectric point, fluorescence intensity (approximate measure of tyrosine and tryptophan concentration) and fluorescence wavelength (microenvironment of the fluorophores) on a single platform. Since there are no stains/tags used, technique is amenable to couple with High Performance Liquid Chromatography (HPLC)-mass-spectrometric measurements.

Swept-source-based optical coherence tomography (SS-OCT) is well recognized for fast imaging rate and long imaging distance; however, due to excess phase noise, there has been very limited success of SS-OCT in quantitative capillary flow imaging in deep cortical layers. A wavelength-division-multiplexing approach is reported to improve the flow sensitivity by minimizing the random phase noises. Quantitative capillary flow imaging is demonstrated in the mouse cortex at 1.6 mm cortical depth based on the proposed method.

Four disease-carrying mosquito species are investigated with a dual-band polarimetric instrument. We report on cross sections for both the insect body and the oscillatory wing component and interpret the results. We find several aspect invariance parameters and contrast for species and sex. We demonstrate benefits for multiple bands. The promising results pave the way for target classification in entomological lidar.

Metabolic characterization of adipose tissues provides remarkable insight into the mechanism of obesity-related diseases. This paper presents a label-free method to assess the metabolism and thermogenesis of mouse adipose tissues in vivo. The optical redox ratio is used as a real-time biomarker to determine the thermogenic response of brown, beige and white adipose tissues to different physiological stimulations. This technique may be used to identify the recruitment and activation of thermogenic adipocytes in animals and humans.

Addition of the inorganic salt potassium selenocyanate potentiates antimicrobial photodynamic inactivation by several logs of killing. This occurs with both Gram-positive and Gram-negative bacteria, and with 3 different photosensitizers, rose bengal, methylene blue and anionic porphyrin 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin dihydrochloride. The mechanism is proposed to be the generation of the pseudohalogen (selenocyanogen) by singlet oxygen oxidation of selenocyanate.