A well established fact of the generation of excited states and photons in biological systems indicates that both life and light are intrinsically associated. This association stems from the electromagnetic nature of the both phenomena. The energetic and informational role of endogenous, spontaneous photon emission is discussed in the framework of two hypotheses attempting to explain the origin, mechanism and biological significance of biogenic radiations.

Human body tissues are relatively translucent to penetrating light what makes possible to perform the effective transillumination for noninvasive measurements os some biophysical quantities by utilization of tissue optics. However, light is strongly attenuated by different tissue components and only proper processing of the transmitted fraction of light at the wavelengths included in the transillumination window, allows us to acquire measurable electrical signals. Volumes of living body parts are cyclically modulated according to the individual arterial pulsations. As a result, making transillumination of a sufficiently thin layer enables to observe rhythmical changes in light intensity transmitted by such an object. Optical density of blood and other tissues is very high, and so, values of light intensity components which are very low, cause many problems with reliability, sensitivity, and range of the detected selective changes. In order to choose a particular device and serve it properly, end-users of medical monitors should always know their advantages and limitations which can be of biophysical as well as technical nature. A lot of artifacts, noises, and disturbances affect the processing procedures and cause the decrease in useful output signals to be converted. On the other hand, there are many problems with empirical verification on human subjects. It is important to solve such complex questions because all the erroneous responses are potentially dangerous. One of the significant diagnostic problems is to detect global as well as local changes in tissue oxygenation which can appear for a lot of reasons. Basing on some novel light on use of the pulse oximetry idea, a model of the living object exposed to noninvasive transillumination can be considered in order to do technical recommendations useful in practice. Such an approach has been presented in the paper from the metrological point of view.

The problems related to the physical processes which occurred during tissues irradiation by laser radiation, from the range of 2 ÷ 3 μm, generated by holmium laser (λ= 2.1 μm) and erbium laser (λ = 2.9 μm), are considered in the article. The interaction of radiation of lasers generating radiation within the above mentioned range is very important problem because in case of high values of the absorption coefficient of radiation in the tissues, the additional interaction mechanisms influencing energy transfer occurs. The radiation energy distribution and temperatures of the irradiated tissue are compared for the chosen types of lasers.

Helium-neon laser irradiation increased production of normal fish hatchlings as a result of eggs irradiation at gastrulation and embryonal motorics stages and negatively influenced at organogenesis stage. Role of main contributing factors-embryos survival and morphological anomalies in this process is investigated.

In experiments on white rats stress was modeled by means of a combined effect of rigid immobilization and sound stimulus (120 dB, 150-500 Hz) for two hours. Just prior to the stress rats of another group were exposed to 15 minute transcutaneous He-Ne laser irradiation (λ - 632.8 nm, power density - 5 mW/cm²). Transcutaneous He-Ne laser irradiation prior to stress prevents its hypercoagulation effect.

Model research was performed on the influence of UV- radiation and ozone on humus substances (HS) - dark ubiquitous biopolymers, the most important component of soil and aquatic organic matter. Aqueous aerated solutions of natural and synthetic model HS (0.001-0.08%) were irradiated with UV - and visible radiation in a flow-circulation system or exposed to the atmosphere containing 0.027 ppm ozone. Control and tested samples were analyzed using the chemiluminescence (CL) method, UV and Vis spectrophotometry and EPR spectroscopy. The results obtained indicate that dry HS are resistant to the UV- and visible radiation and low concentrations of ozone. However, HS is aerated solutions undergo degradative oxidation. These exergonic reactions are accompanied by the generation of electronically excited states and free radicals that manifest as a CL and changes in EPR signals. Prolonged irradiation or exposure to ozone causes a gradual degradation of the aromatic core of HS to hydrophilic, low molecular carboxylic products. Mechanisms of the degradation reactions, CL, changes in EPR signals and optical density of HS are proposed and possible ecological consequences of these processes are considered.

By means of the new method of transmission-resonance EHF/SHF radiowave spectroscopy alteration of the resonance structure of water, whole blood, blood plasma, serum and erythrocytes haemolysate under the influence of He-Ne laser radiation was established.

It has been shown that NO is released under the exposure of the aqueous solutions of S-nitrosocompounds as well as blood plasma proteins and whole blood of healthy donors to UV and visible light. In addition to NO, thyil radicals which dismutate to disulfides, are formed under anaerobic conditions. In the presence of oxygen, peroxide compounds, cysteine acids derivatives are formed apart from disulfides, and NO is mainly converted to NO₂^-. It is suggested that NO released under the action of UV and visible light from physiological depots induces vascular relaxation, which enhances the blood flow.

This paper is devoted to problems with reliability of the fluorescence analysis in investigating the DNA chains. Relationships between thermodynamic and optical properties of a given sequence are taken to consider modeling of a virtual light-directed library of oligonucleotides. Specificity of changes in optical density caused by specific interactions between pairs of DNA bases depends on the known nearest neighbor model which has been assumed here as the background. If to assume an integrated array of the known oligonucleotides (L-mers) which all have their own stable locations, after hybridization we may obtain a fluorescence result creating a matrix of micro-images; each one corresponds to the optical answer of a given oligonucleotide included in the investigated sequence spectrum. A presented concept of interpretation of fluorescence effects depends on relation between a given level of optical density and order of the bases included in oligonucleotides involved in hybridization procedure. The factors influencing fluorescence image attributes, including signal levels and stability as well as resolution and accuracy of sensing, are discussed. The obtained results of comparative computations made on a normal and simulated abnormal composition of a given human sequence are illustrated at the case that L = 6. Basing on consequences of changes in melting temperature, thermodynamic stability and levels of fluorescence light intensity, the optical spectra are presented as images made by sites of full hybridization put on a reference thermal map.

In vitro measurements of levels of ultraweak luminescence were carried out using healthy and malignant tissues obtained from 63 patients undergoing surgical operations for cancers of colon, stomach and breast. The results obtained support recent reports that there is a difference in mean intensities of the ultraweak luminescence emitted from healthy and malignant tissues. This work demonstrates, however, that because of a large scatter among the intensities detected for samples obtained from different patients the differences found for the mean intensities cannot serve as a parameter for differentiating between the malignant and normal human tissues.

We studied spectral and spatial distributions of the intensity of the ultraviolet light-excited fluorescence of human skin. Our studied performed in situ in 162 patients with malignant and non-malignant skin lesions resulted in a new method of detecting melanomas in situ using digital imaging of the spectrally resolved fluorescence. With our diagnostic algorithm we could successfully detect 88.5% of the cases of melanoma in the group of patients subject to examinations with the fluorescence method. A patent application for the method has been submitted to the Patent Office in Warsaw.

Images of the laser-induced fluorescence (325 nm, He-Cd laser) were recorded in vitro in six regions of a visible spectrum using a cooled CCD camera. Images were taken sequentially and then processed to assess the ability of such an approach to detect and to localize cancer tissues. 72 areas of 21 resected specimens were examined. It has been established that a difference of fluorescence intensities measured at 440 nm and 395 nm, both normalized to intensity measured at 590 nm differs significantly for the neoplastic and non-neoplastic tissues of interest. Using this quantity as a diagnostic parameter it was possible to classify malignant gastric tissues with a sensitivity of 96% and a specificity of 42% while the same approach applied to abnormal stomach tissues gave respectively values of 80% and 98%.

We report the results of feasibility studies on using digital imaging of the laser-induced autofluorescence of colonic tissues for a detection of premalignant and malignant lesions of human colon. Images of the autofluorescence excited with 325 nm line of He-Cd laser were recorded in vitro in six regions of a visible spectrum using a CCD camera. A total of 126 areas on 30 tissue specimens was examined. At all the spectral bands selected the intensity of the fluorescence of the neoplastic tissues was lower than that of the normal mucosa. The ratio R of the intensities of the autofluorescence of normal and abnormal tissues measured with the 440 nm filter was found to be a sensitive diagnostic parameter for detecting adenocarcinomas. This parameter is less sensitive in detecting adenomatous polyps and does not differentiate polyps with different degrees of dysplasia.

In this study we present the comparison of neutrophils activity, measured in whole blood by a chemiluminescence test in children with bronchial asthma and recurrent respiratory tract infections (RRTI). We estimated five parameters of chemiluminescence: I - a time of spontaneous stabilization of CL (following counts remain on the same level with a tendency to decrease), II - a time of maximal CL excitation (time after addition of stimulator during which the cells emit the highest amounts of photons), III - an average value of spontaneous CL (from the beginning of measurement to the addition of f-MLP), IV - a maximal value of CL after stimulation and V - and area under CL curve. The values of parameters III, IV and V were significantly lower in the children with rrti (p<0.0001) than those in the control group. The neutrophils' activity, reflected in measured parameters of CL, was several times greater in the children with bronchial asthma than that in the control (p<0.0001) and RRTI (p<0.0001) groups. A deterioration of oxygen metabolism of neutrophils, measured by CL test, was demonstrate in children with rrti.

Use of lasers in dentistry dates back 20 years but is still not fully exploited, especially when concerning the hard dental tissues. Over the past many efforts and actions have been involved in testing and developing new methods for caries diagnosis. The implementation of these methods in general dental practice is unfortunately still limited because too little scientific evidence exists to support them. One of the age-old concerns for dentists is that decay is often discovered too late. Dentists commonly use x-ray imaging for early caries detection, but this method cannot reveal decay at a sufficiently early stage to avoid restorative methods. Generally, if a caries lesion si detected by x-ray, the mineral loss within the tooth is normally very high and will need invasive treatment. Several laser based techniques, as also other optical methods of detecting caries lesions at an early stage seem to be very promising. Fluorescence of tooth structure is observed when hard tissues are illuminated using laser light. Decayed areas appear dark and provide a contrast against the healthy background surrounding them, so discriminating sound and carious tissues. The aim of this study was to present the possibilities of using laser induced fluorescence in the diagnosis of early caries lesions. The current state-of-the-art is presented, as well as results of our investigations. In our studies an argon ion laser was used to illuminate the teeth and the fluorescence pictures were captured with a CCD camera and then analyzed. Results confirmed that laser induced fluorescence can be used as a sensitive method of caries diagnosis.

The fluorescence properties of anthocyanin pigments in extracts of red cabbage, Brassica oleracea, have been studied. The fluorescence spectra and fluorescence excitation spectra have been measured with absorption spectra of anthocyanins in extracts at pH 2 and pH 7. The results of the researches show that kinds of fluorescent anthocyanins (or/and other compounds) depend on pH conditions of red cabbage extracts. The properly chosen parameters of fluorescence measurement allow to distinguish spectrally two different fluorescent anthocyanin compounds in extract at pH 2 in comparison to pH 7, where three fluorescent compounds have been found.

A new method and apparatus for vital investigations of mammalian and human organs - the method of contact microscopy - is described. A number of contact microscopes for investigations in biology and medicine as well as the results of their application are presented.

A number of contact luminescence photometers and spectrophotometers were worked out at SOI for estimation of functional state of living tissues and organs, and the pathological condition of organism in particular. Contact double-wavelength microfluorometers were designed for fluorescence measurements of pyridine nucleotides and flavoproteids. There are two design modifications of the microfluorometers for biopsy diagnostics and for use during the time an operation. Intraoperation luminescence probe makes it possible to evaluate the status of the blood microcirculation in an organ as basic induce of the vitality of tissues and organs during surgical operations. Processing of this instrument is based on luminescence angiography. A fiber-optic medical spectrophotometer is for fluorescence spectra registration of skin local sections in the region 400-800 nm. Some examples of the clinical use of these apparatus are described.

Different types of luminescence image analyzers based on the use of special wide field optics combined with CCD cameras as light detectors are designed by the authors. Principal schemes of these instruments are defined by different modifications of sequencing by hybridization method.

We describe cytometric system based on optical microscope for cell optical and photothermal quantitative studies. The developed methods are aimed to provide live cell analysis including monitoring, type and state differentiation. The developed image cytometry system was applied to the studies of the blood cells (RBC, WBC). Cell populations were analyzed through the 22 cell parameters. For parameter control aid optimization special objects that model the cells have been used. The hardware and software that provides image acquisition, processing and analysis are designed on modular principle. The results of cell studies have proven that the combined analysis of the two or three images of cell yields more information on cell for cell diagnostics. The developed system in its hardware and software are complementary to the optical microscopy.

Photothermal imaging, when being applied to the study of living cells, provides morpho-functional information about the cell populations. In technical terms, the method is complementary to optical microscopy. The photothermal method was used for cell imaging and quantitative studies. Preliminary results of the studies on living human neutrophils are presented. Differences between normal and pathological neutrophil populations from blood of healthy donors and patients with saracoidosis and pleuritis are demonstrated.

The immune reactions of interaction antigen-antibody represent specific effect of an antigene with an antibody, which outcome are the complex immune aggregates forming precipitate in case of a soluble antigene, or agglutinate in case of a corpuscular antigene. Immunological methods which uses in the quality of carrier protein latex's polymeric microspheresis, gained name and method latex agglutination. Polymeric microspheresis have the array of advantages before biological carries, which consist in the opportunity of the variation of attributes surface and size microspheresis in the broad band of meanings with the preservation of narrow distribution particles behind measurements, the putting of functional groups, necessary for bunch with ligand on stage their synthesis, in ragidity at storage. The quantitative evaluation of parameters of a response of interaction antigen-antibody in immunology is possible by optical methods on a measurement of a modification of intensity of a light stream of a solution in an outcome of a course of a reaction. Concentration of immune complexes determine both on slacking a taking place stream of light, and on a modification of intensity of a stream of light scattering suspended particles in a solution. The process light scattering by colloidal aggregates are formed from suspension microspheresis with adsorbed on their surface protein is described. In report the physics principle of registration immune reaction by light scattering methods is concerned. The results of the effectiveness latex's preparation created on basis of the polymeric carries is described.

In the paper on the base of theoretical and experimental analysis it is shown that the spectrum of intensity fluctuations contains the high frequency peak in the absence of subsidiary reference wave at non-small angles of speckles observation. Such phenomenon, interpreted as new type of manifestation of Doppler effect, is habitual only for the case of strongly focused coherent beam scattering. In the paper the possibilities of the usage of observed effect in the measurements of blood flows in narrow capillaries are discussed. Traditional Doppler method utilizing the strongly focused Gaussian beam scattering is considered. It is shown that the frequency position of Doppler peak in the spectrum of intensity fluctuations of measurements is defined not only by the angle of speckles observation but also by the relation between the waist beam diameter and the average size of flow inhomogeneities. Such result was experimentally verified.

The measuring method of microcirculatory parameters using strongly focused Gaussain beam (SFGB) diffraction phenomenon has been proposed in this paper. The method has been applied for the investigation of lymph flow characteristics in microvessels in vivo. Intensity, fluctuation spectra of a scattered field which are the result of laser beam diffraction in lymph vessels have been presented in the paper. It has been shown that the alterations of spectra shape depend on peculiarities of lymph motion in microvessels. Physical parameters of determination both of temporal changes of mean velocity and of spatial-temporal velocity distribution in lymph microvessels have been proposed. An action of lymphotropic drug on the lymph flow parameters have been studied.

The results of an experimental study of the effect of vibrational motion of human skeletal muscles on the intensity fluctuating spectrum of the dynamic speckle field scattered by the skin are reported. It has been found by experiment that the area under the spectral curve of the speckle-optical myogram increases in proportion to the applied isotonic load until it reaches 80% of the maximum effort of the patient's brachial biceps. Further increase in isotonic load up to the maximum effort leads to a decrease in the vibrational activity of the muscle. Comparative analysis with electromyographic data has shown that traditional method fail to register this change.

Results of an investigation of the cutaneous blood flow in patients with neurological manifestations of the lumbar osteochondrosis using a laser speclometer devised by us are presented. Comparative analyses of the data obtained form infrared examination and dermatothermometry revealed great informative value of speckle-optical indices. The dynamics of the cutaneous blood flow in patients corresponded to the change of the high-frequency spectra of fluctuations.

Bone tissue samples excised from the femoral heads of human were X-rayed together with the aluminum reference standard of density. The radiograms were scanned with the laser densitometer UltroScan XL (Pharmacia). Form the optical density profiles of bone samples the mean optical densities were determined. The optical densities were recalculated into equivalent thickness of the aluminium standard [mm Al]. Inter-measurement reproducibility of optical density determination was found to be very good (SD less than 3% of the mean). Relatively high variability (SD about 13% of the mean) was found for the optical density determination of a single bone sample X-rayed repeatedly. The inter-individual variability, which reflects the variability of bone tissue density between human subjects, was estimated as about 25% (SD as percent of the mean). We concluded that the laser densitometry performed according to our protocol provides the precise estimation of bone tissue density. Therefore, laser densitometry of bone tissue radiograms is potentially useful method for studies of bone in medical research and diagnosis.

A spectrophotometric method optical density ratio for simultaneous determination of four derivative as for deoxyhemoglobin, carboxyhemoglobin and methoemoglobin in a blood sample is described. The normalized averaged spectrum of derivative hemoglobin in the spectral range 14200-21000 cm^-1 is reduced.

The short outline of random dot autostereograms is presented. First a concise historical sketch of basic notions and concepts used in theory of stereoscopy is reminded. Then two principal techniques of the random dot autostereograms perception are explained. At last the design of autostereograms is shortly discussed, as well as the mechanisms which enable perception of these stimuli.

This paper is dedicated to computer-aided modeling of attributes of human tissues which are exposed to determined light action for measurement purposes. The transmission mode of light-tissue interaction is assumed. By use of either cross-section or longitudinal section of a multilayered tissue slab with planes perpendicular to the direction of light action, respectively, two dimensional representation of 3D structure is considered. In such an approach, effects resulting from light transmission can be studied for the light intensity vector in the rectangular coordinates. The proposed structure of a specialized algorithm makes it possible to create free variants of reference standards, including changes in a number of layers and their biophysical compositions. Exemplary results of calculations for the tissue slab transilluminated in x-y coordinates are presented, at red light to be acting. The major aim of further works is to carry out an atlas of variants modeling optical properties of living tissues which one could be a comprehensive source of standard data and real measurements based on utilization of light transmission through an object to be investigated.

The principle and applications of the projection moire and grid/fringe projection methods for the shape determination in medicine are presented. The attractiveness of the methods due to their non-invasive and non-contact character is emphasized. The measurements are whole field and can be readily automated. The application examples included are focused on the computer aided studies of the shape of the muscle-osseous system and postural deformities.

Optical imaging and spectroscopy of objects inside high scattering medium by use of light instead of X-rays are named an optical tomography. The optical tomography applied for medical diagnose seems to be very promising due to low risk of genetic changes inside living cells during visible and infrared photon treatments of tissue in contradiction to the X-ray examinations. The aim of the paper is to present short an overview of different kinds of the medical optical tomography. The main attention is done for current problems of the medical optical tomography. Some results of clinical tests of an optoelectronic mammoscope based on two wavelength transiluminance method for breast cancer imaging are presented as well.

The aim of this paper is to present a method of optical imaging of the objects inside high scattering media. An idea of two-wavelength tomography is based on application of differences in absorption spectra of transmitted light for two selected wavelengths i.e. 670 nm and 810 nm. In the first part of the paper a theoretical background of optical tomography is done. Radon transform procedures for monochromatic light as well as for two-wavelength case are given. In the second part of the paper results of experiments carried out in laboratory by use of two laser diodes as a light source and CCD camera controlled by computer as a detector are presented.

Optical coherence tomography (OCT) is a noninvasive imaging technique which provides microscopic tomographic sectioning of biological samples. This contribution presents a new spectral OCT technique, which allows to detect the phase of detected signal and thereby to remove the useless low- frequency terms from the registered signal. The basic principle is shown and experimental measurement sin vitro and in vivo are presented.