Results of hyperspectral imaging analysis for in vivo visualization of skin neoplasms are presented. 16 melanomas, 19
basal cell carcinomas and 10 benign tumors with different stages of neoplasm growth were tested. The HSI system
provide skin tissue images with 5 nm spectral resolution in the range of 450-750 nm with automatic stabilization of each
frame compensating displacement of the scanning area due to spontaneous macro-movements of the patient. The
integrated optical densities in 530-600 and 600-670 nm ranges are used for real-time hemoglobin and melanin
distribution imaging in skin tissue. It was shown that the total accuracy of skin cancer identification exceeds 90% and
70% for differentiation of melanomas from BCC and begihn tumors. It was demonstrated the possibility for HSI
classification of melanomas of different stages.
The problem of cancer control requires design of new approaches for instrumental diagnostics, as the accuracy of cancer detection on the first step of diagnostics in clinics is slightly more than 50%. In this study, we present a method of visualization and diagnostics of skin and lung tumours based on registration and processing of tissues hyperspectral images. In a series of experiments registration of hyperspectral images of skin and lung tissue samples is carried out. Melanoma, basal cell carcinoma, nevi and benign tumours are studied in skin ex vivo and in vivo experiments; adenocarcinomas and squamous cell carcinomas are studied in ex vivo lung experiments. In a series of experiments the typical features of diffuse reflection spectra for pathological and normal tissues were found. Changes in tissues morphology during the tumour growth lead to the changes of blood and pigments concentration, such as melanin in skin. That is why tumours and normal tissues maybe differentiated with information about spectral response in 500-600 nm and 600 – 670 nm areas. Thus, hyperspectral imaging in the visible region may be a useful tool for cancer detection as it helps to estimate spectral properties of tissues and determine malignant regions for precise resection of tumours.
The effect of increase in the uncertainty of local polarization states of laser light forward scattered by random media was studied in the experiments with phantom scatterers. At macroscopic level this effect is related to decay in the degree of polarization of scattered light in the course of transition from single to multiple scattering. Gelatin layers with embedded titania particles were used as the phantom scatterers. Features of distributions of local polarization states in various polarization coordinates were considered.
Experimental studies of optical parameters of different atmospheric bioindicators (arboreous and terricolous types of plants) have been performed with Raman spectroscopy. The change in the optical parameters has been explored for the objects under direct light exposure, as well as for the objects placed in the shade. The age peculiarities of the bioindicators have also been taken into consideration. It was established that the statistical variability of optical parameters for arboreous bioindicators was from 9% to 15% and for plants from 4% to 8.7%. On the basis of these results dandelion (Taraxacum) was chosen as a bioindicator of atmospheric emissions.
In this work the results of research of heavy metals impact on aquatic plants with Raman spectroscopy are shown. The peculiarity of Raman spectrum under the influence of heavy metals has been experimentally established. Optical coefficient, determining heavy metals impact on aquatic plants was introduced. It was defined as correlation of Raman intensity values on wave numbers 1547 cm-1, 1522cm-1 to intensity band value at 1600 cm-1. Microscopic analysis of aquatic plants under the influence of heavy metals has been conducted.
In this work the results of cell-tissue grafts research with a complex of optical methods – confocal fluorescent microscopy and Raman spectroscopy are presented. It was established that coefficient M scatter is related to irregularity of demineralization process. It was microscopically shown that the quantity of integrated cells into these types of transplants amounts to 20% of its surface.
One of the complicating factors for environmental situation is degassing of land. The high concentrations of hydrogen near the bearing metal structures can weaken them as a result of embrittlement. Therefore, the study problems of hydrogen concentration in the soil and hydrogen influence on living organisms are relevant. However, the exit of deep hydrogen has a volley character. This problem can be solved by the plant bioobjects as the local integral indicators. The dandelion (Taráxacum) was selected as the research object. The collection of objects was produced from the degassing zone and a zone without degassing. Selection of degassing zone was driven by information that was provided by the Volga branch of the Institute of Geology and Exploration of fossil fuels of the Samara Region. Experimental studies of the hydrogen influence on the optical properties of plants were conducted using a complex of Raman spectroscopy and confocal microscopy. Laboratory and field research were conducted. Raman spectroscopy was implemented using the experimental stand that includes a radiation source, a fiber system for collect and feed of radiation and SR-303i spectrophotometer with integrated digital camera ANDOR DV-420A-OE (1024 * 256). The experimental stand allows to work in the spectral range of 180 - 1200 nm and with a registration accuracy about 0.2 nm. A detailed analysis of the structural changes in plant cells under the hydrogen influence was performed by confocal microscopy.
The research results of monitoring of viable cells in a cellular-tissue graft using confocal laser fluorescence microscopy at 488 nm and 561 nm with the use of fluorophore propidium iodide (propidium iodide, PI Sigma Aldrich USA) are presented. The processing of the received images was carried out using the software ANDOR. It is experimentally shown that the method of confocal fluorescence microscopy is one of the informational methods for detecting cells populated in a 3-D bio-carrier with a resolution of at least 400 nm. Analysis of the received micrographs suggests that the cells that were in a bio-carrier for 30 days in a synchronous ground-based experiment retained their viability compared to a similar space-based experiment in which the cells were hardly detected in a bio-carrier.
Experimental study of the hydrogen influence on the optical characteristics of plants by Raman spectroscopy was performed. Research revealed the amplitude increase of Raman intensity in wavenumbers 1130 cm-1 and 1495 cm-1 for plants under hydrogen influence. The structural changes in the plant leafs were identified by fluorescence confocal microscopy. Experimental study of kinetic processes of plant tissue has shown the emergence of plant reaction to external impact (hydrogen). In turn, the plant response manifested to Raman intensity increase and leads to increase of stem thickness.
The results of experimental studies of donor bone samples (rat, rabbit and human) with varying degrees of
mineralisation by Raman spectroscopy were presented. Raman spectra were obtained for the Raman bands 950-962
(РО4)3-, 1065-1070 (СО3)2- and 1665 cm-1 (Amide I).
In demineralized bone a sharp decline (to 98 %) in the range of 950-962 cm-1 (РО4)3- and 1065 - 1070 cm-1 was
observed. This decrease was accompanied by the emergence of the 1079-1090 cm-1 band corresponding to the hydrated
The experimental study results of spectral characteristic change of different types of plants influenced by external
factors (synthetic superficially active substances, salts of heavy metals and nitrate fertilizers) are presented. Differential
optical factor was used as the monitored optical parameter that characterizes the chlorophyll concentration change. The
differential backscatter method which has high test-sensitivity and provides with the most complete information on the
plant condition was the main optical monitoring method. For understanding the mechanisms of external factor accumulation
and influence on plants the confocal fluorescent microscopy method providing contrast micrographs of high resolution
was used for microscopic analysis in the study.
It was revealed that synthetic superficially active substances and heavy metal presence lead to quasilinear decrease
of differential backscatter factor with time. It was shown that the presence of salts of heavy metals in a water solution
leads to chlorophyll "binding" which is microscopically shown as their «adhesion» near the cell membranes. On the
contrary, the presence of synthetic superficially active substances maintains the uniformity of chlorophyll distribution in
a cell, but its concentration falls with increasing the concentration in a major emission. The latter depends on the fact that
synthetic superficially active substances solubilize the cell membrane proteins, increasing its penetrability. It causes
pigment release ("washing away") from a plant, thereby leading to differential optical factor change.
It was shown that nitrate fertilizer presence leads to increase of differential backscatter factor with time which is
microscopically connected to increase in chlorophyll concentration.