Boris A. Medvedev

Comparative analysis of the marrow and blood spectra

It has been found experimentally that exposure to a low-intensity light changes the human blood plasma absorption spectrum in the range 350 - 550 nm. The action of violet light and green light have opposite directions. The times of development of photoinduced effects are in the order of dozens of seconds, the times of spectrum relaxation after the exposure are in the order of dozens of minutes. Dependences have been studied of the effect on the intensity, dose, and wavelength of the acting light. A phenomenological model is developed which describes qualitatively the experimentally observed effects.

Mathematical model of erythropoiesis dynamics under low-intensity laser and x-radiation

The mathematical model is presented of low-intensity laser radiation influence on the dynamics of the X-irradiated bone marrow tissue erythropoiesis. The process of recovering in postradiation stage of the cells of erythroid series has been investigated for various parameters of laser emission.

Mathematical modeling for laser PUVA treatment of psoriasis

The justifaction of method of the laser PUVA (LPUVA) therapy, the description of an UVA therapeutic system, the preliminary results of using the nitrogen gas laser as an UVA source for LPUVA chamber and in some other fields of application in dermatology are given.

Mathematical model of laser PUVA psoriasis treatment

In order to optimize laser PUVA psoriasis treatment we develop the mathematical model of the dynamics of cell processes within epidermis. We consider epidermis as a structure consisting of N cell monolayers. There are four kinds of cells that correspond to four epidermal strata. The different kinds of cells can exist within a given monolayer. We assume that the following cell processes take place: division, death and transition from one stratum to the following. Discrete transition of cells from stratum j to j + 1 approximates to real differentiation.

Nonlinear cellular dynamics of keratinocytes in normal and psoriatic epidermis under action of UV radiation

The semi-phenomenological model of epidermal cell dynamics is submitted. The model takes into account three types of basal layer keratinocytes (stem, transient amplifying, terminally differentiated), distribution of first two types cells on mitotic cycle stages and resting states, keratinocytes-lymphocytes interactions that provide a positive feedback loop, influence of more differentiated cells on their progenitors that provide a negative feedback loop. Simplified model are developed and its stationary solutions are received. The opportunity of interpretation of some received modes as corresponding to various stages of psoriasis is discussed. Influence of UV-radiation on transitions between various modes of epidermis functioning is qualitatively analyzed.

Modeling of cell proliferation processes and nonlinear optical effects at pulse laser PUVA-therapy

In this work the mathematical model presented describes the processes in the epidermis sensitized by the furocoumarins under UVA-radiation of pulse laser.

SPECTROSCOPIC METHOD OF DIAGNOSTICS OF THE BONE MARROW AND PERIPHERAL BLOOD

The first results of comparative spectral analysis of the bone marrow and blood taken from one and the same donor are presented and the new potentialities of the spectroscopic method for hematologic diseases diagnostics and for testing the pathologic process together with the morphologic investigations of bone marrow punctates are considered. We present here the results of comparative spectral analysis of the bone marrow and blood taken from one and the same donor. We found out what differences in spectra are for normal and pathology bone marrow composition and what causes this difference.

Mathematical model of hemopoiesis dynamics under low-intensity laser and x radiation: approach to development

Some biophysical and mathematical aspects of development of computer model of low-intensity laser radiation influence of the dynamics of the X-irradiated bone marrow tissue hemopoiesis are discussed.

Mathematical model of erythropoiesis dynamics under low-intensity laser and x radiation

The mathematical model is presented of low-intensity laser radiation influence on the dynamics of the X-irradiated bone marrow tissue erythropoiesis. The process of recovering in postradiation stage of the cells of erythroid series has been investigated for various parameters of laser emission.

Order and chaos in living organisms

One of the main means of studying the essence of the laws of process dynamics in living systems is mathematical modelling. Construction of adequate mathematical models is not quite simple a problem and demands joint efforts of physicists, mathematicians, medical men, and biologists. Models can be of different levels of complexity. I would like to confine this discussion to only one of the dynamical processes description methods, that is, by means of ordinary differential equations. At the same time we will not consider spatiatemporal (wave) processes that are the subject for a separate discussion.