SOME TRENDS IN MATHEMATICAL MODELING FOR BIOTECHNOLOGY

The purpose of this publication was to show some trends of the development of modeling methods for biotechnology according to contemporary achievements in science and technique. Common approaches were outlined, some types of classification of modeling methods were considered, the role of methods of mathematical modeling in biotechnology in conditions of intensive development of information computer technologies was highlighted. The appropriate scheme of their interrelation was proposed. Several examples and mathematical models in three dimensions (1D, 2D, 3D models) were described respectively for processes in living objects at different levels of their hierarchical organization. In course of this research, the main attention was paid to some processes modeling in neurons, as well as their aggregates of different forms, including the cellular formation of glioma (1D, 2D, 3D brain processes models). Their consideration was begun with the models that had today only theoretical importance and was completed with a description of a model that might has practical application. The work was done after the analysis of approximately 250 current publications in fields of biotechnology, including the authors’ original works.

Intensive development of computer facilities, information technologies and advanced training of scientists in the field of mathematical methods made it possible to apply increasingly complex methods for modeling in biotechnology; and this practice demonstrates a lot of advantages. Using modeling, the researcher can test well the structures of complex system and processes in it without invasion into this system [1]. Simulation can also be used in situations, when the system's behavior is not clear enough (models of "black box" or "grey box") [1]. Using some models, one can simulate the dynamic behavior of the system over a period of time [1]. Also, the methods of modeling permit to study the biotechnical system in cases, if invasion in it functioning is enough expensive or can damage the system by itself (in cases of biotechnical production, processes in living organism, and etc.) [1]. In our previous publications [1,2] we analyzed a number of mathematical analytical methods for data processing in biotechnology, and outlined that some types of mathematic analysis have already become widely used: factor, dispersion, correlation, discriminant ones; as well as methods of classification, other methods of statistical data processing [1,2]. Special attention we paid to some powerful mathematical methods used in biotechnology, like neural networks [3], cluster analysis [4], image processing [5]. In the format of this article it was impossible to observe the great volume of publications devoted to task solutions using contemporary methods of modeling. So, at the beginning of this article some general approaches were outlined; some principles of classifications of mathematic modeling methods were suggested. Than we tried to demonstrate our understanding of the place of mathematic modeling methods among other mathematic methods from the point of view of information computer technologies (ICTs); we suggested also an appropriate scheme of their correlation. Further some case studies were represented: some suitable mathematic models are suggested for the description of different processes in living objects of different levels of organization. We would like to suggested a few models of the brain or brain elements of different level of hierarchical organization. Respectively, these models we ordered as models of different number of dimensions (D): 1D model, 2D model and 3D model. We started from some models that have theoretical importance for today only -we outlined some examples of modeling techniques and software tools that can be used to simulate cellular networks and systems. Than we described a model of glioma with forecasting of patients life expectancy; we hope this will be important for the practice.
Mathematical models in biotechnology: basic concepts. There were a lot of contemporary publications where are stated, that mathematical models are tools that we can use to describe the past performance and predict the future performance of biotechnological processes . Methods of mathematic modeling could be applied to processes operating at many different levels, from the action of an enzyme within a cell, to the growth of the cells within a commercial scale bioreactor; these methods were widely used for the development of bioinformatics methods, for the newest biomedical electronic information systems elaboration [1,11,74,. Mathematical models could be powerful tools in both fundamental research and applied research; for their development the newest mathematic methods were used usually [1, 2-5, 41, 60-62, 66-74, 76-77, 116]. Mathematical models were important tools in the optimization of the performance of biotechnological processes. There were numerical excellent publications in this sphere with the description of analysis of mathematical models' structure, demonstrated how they contain state variables, independent variables, operating variables and parameters, and etc. [1, 7-10, 13-16, 18-28, 34, 63, 64, 75, 80]. Such publications contained usually some case studies, in which, for example, the differential equations were used to describe the operation of a simple enzyme reactor, and etc. Sure, the real experimental results and results of observations were put in base of such models [1, 12, 17, 28-40, 72-74, 134-155]. These provided the basis for discussion of the various approaches that could be used in modeling, such as empirical versus mechanistic approaches, or structured versus unstructured approaches [7].
Classification of mathematic models. Great variability of the types of mathematical methods was developed during all period of this practice existence [1, 2-5, 41, 60-62, 66-74, 76, 77, 116]. Probably, according to the most general contemporary classification all models could be subdivided to 1 -physical, 2 -mathematical, and 3 -computer ones. 1 -Physical model, for example, engineers can elaborate like any device, or smaller copy of bioreactor for biomass cultures; in such a way its functional abilities might be checked.
2 -Mathematical models were developed as a set of mathematical expressions for description of biotechnological processes; the main abstractions and regularities of modeled processes have to be revealed carefully.
3 -Computer (or program) models meaned an algorithm and/or codes for the simulation (or imitation) of biotechnological processes.
Also, there were some attempts to group mathematical modeling methods for their classification. One such classification was done by the group of Ukrainian cybernetics who worked for biology in Kyiv, on 1970-th -1980-th: Piatigorsky B.Ya., Zaitman G.A., Cherkasky V.L., Chinarov V.A.(Kyiv, Ukraine, 1985) [1,9,10]. Groups of modeling methods are represented below according to their works as a number of alternative pairs (Fig. 1).
In one of more recent publication there were represented another classification, also based on contradictory pairs [7]. Types of models according to these authors were following (Fig. 2).
Because of fast progress in contemporary ICTs' spheres another types of classifications were possible as well. Below in this publication there are the results of authors' original research in modeling (mathematical and program ones as well) [1-5, 15, 16, 18-37, 60-66] and mathematical processing of biological data , as well as a brief review of some other authors works in modeling [6-8, 11, 37-57, 67-133].
Contemporary information technologies: from models to information systems. Practice of mathematic modeling in biotechnology is seen as traditional one nowadays. From the other side, our époque is characterized by extremely intensive development of ICTs that obtain numerous forms and manifestations. Our task was to find the links between traditional mathematic modeling and modern ICTs; the results of such studying were described before in [1]; they are shown also at Fig. 3.
At the center of picture "Mathematical modeling" was placed as an extremely important compartment of methods and knowledge in computer disciplines, which is considered classic today. Until the early 1990s -the time of intensive development of information computer technologis -mathematical modeling occupied a priority position. This compartment produces the source data, models, methods, and etc.; all these had found an application in practice, which is presented at figure as compartment "Technical application". Such practical application meaned elaboration of various mechanisms or devices, for example robots, expert systems, automatic devices, other computer-controlled systems.
Process of development of notion "Information computer technologies" and its correlation with notions "Databases" and "Mathematic modeling" might be demonstrated as few historical stages (Fig. 3).
1) Initially, for models that were created at the historic "Stage 1" not so much input data were needed; sometimes such data could be given even as a simple table representation on a sheet of A4 format.
2) At the "Stage 2" we showed the continuation of this historical process.   [7] The amount of data that needed processing grew rapidly with time, and the input of "Mathematical modeling" began to present data structured in the form of simple databases (DB) (for example, using the first versions of DBase or FoxPro according to shown at (Fig. 3).
3) Due to the technical progress, increased power and speed of computers, the transition to personal computers (PCs) and the formation of networks, there were prerequisites that DB acquired their own increasing importance (Stage 3). With the time DB control systems have been so advanced and developed that many of the preparatory data operations became possible to be realized even before the data entered the part "Mathematical modeling". At the next step the level of development of input data operations became very high. This resulted in the "Information Technologies" developed with DB and included in them; and this structure could be isolated in a separate compartment as shown at figure for Stage 3. At Stage 3 of information systems (IS) development, the subset "Information technologies" included "databases".
Today we can state that at the current level of information computer technologies development the different methods and technologies coexist successfully: older in time of their invention as well as the latest ones. Their significance and role in the modern world is determined not by the time of their creation, but how much they are needed in practical human activity.
Description of some mathematic models. So, the methods of mathematic modeling could be used nowadays for the solution of different tasks in biotechnology. Such practice began even from the first steps of computer use; in Kyiv, Ukraine there were the works of 1950-60-th years of cybernetics who worked for biology: Amosov N.M., Hlushkov V.M., Kostyuk P.G., and later -representatives of their scientific schools Shkabara E.A., Ivanov-Muromsky, Piatigorsky B.Ya., Onopchuk Yu.M. and many others [1,10,11]. It was not possible to list all tasks solved by these representatives of Kyiv scientific schools of cybernetics during few decades until XXI century. The numerical models of different types of processes in nervous systems, in cells and cell aggregates, biological objects, biological organism functioning, models of experimental biotechnological equipment, and many others were elaborared.
Intensive works in this direction were carried out through over the world. For example, in publications [1,[6][7][8][9] there were a lot of other models' descriptions. In work of [7] there was a mathematical model developed for enzyme reactor consisted on a reservoir containing a substrate solution which circulated through the column with immobilized enzyme; the use of this model for the estimation of enzyme kinetic constants was demonstrated. Also there was a structured metabolic model developed in 1984 for the growth studying of a single Esherichia coli cell and etc. Authors in [6] outlined modeling techniques and software tools that could be used to simulate cellular networks and systems. First, they presented a review of stoichiometric models and Flux Balance Analysis and then discuss continuous deterministic models composed of ordinary differential equations. Next, they presented the continuum descriptions, often used for the simulation of model signal transduction and gene expression programs with stochastic models. Lastly, they discussed the application of qualitative modeling tools and techniques such as fuzzy-logic and petri nets to the problem of modeling complex intracellular networks. For the illustration of abovementioned basic concepts a few case descriptions were suggested. 1D mathematic modeling of electrical currents in biocells. Electrical signal transmission through myelinized fiber. The excitation spreading in myelinized fibers is seen as classic example of 1D mathematic modeling of electrical signals transmission in nervous system. If the maximal action potential significantly exceeded the threshold and if the front of potential rise is sufficiently narrow, the potential increase was very fast. It could be assumed that the excitation transfer occurs from one Ranvier node to the nearby node and subsequent nodes influenced only slightly one on another. This task solution leaded to a problem with distributed and lumped parameters [13,14]. In case suggested below it was supposed that the action potential is many times greater than the threshold, and the front rise of potential was equal to 1.5-2 intervals between the Ranvier nodes [13,14]. So, the intervals between the nodes formed the distributed system and the potential change in it could be described by the equation if i = 0. For simplicity there were used dimensionless variables, namely, the coordinates are measured in intervals L, and the time t -in units of R 1 C 1 . For such cases the equation for the potential at intervals looks like much simpler: Lets also suppose that at time T = 0 the excitation started at the node located in point X = 0 due to the mechanism of membrane potential changes in it, and according to (2).
Electrical current generated by this node initiated processes in the next node. So, charging capacity of myelinized interval and capacity of the next node located at X = 1. Then there were assumed that processes at the next node (charging node X = 2) did not occur until the time of stimulus "hopping" at excitation node X = 1. Therefore for boundary conditions at X = 2 it was possible to assume that T= 0 Presence of lumped capacitance C 2 at Ranvier node and at the point X = 1 was reflected by the simple expression It was assumed that at point of process start X0= 0.
This may be in case of significant difference between the threshold and action potentials, and the presence of small initial charge on the fiber had not significant influense on results.
The task was solved under the condition 0< T < T L , where T L -magnitudeless dimensionless time of excitation "hopping" from one node to another. The purpose of task was to calculate the time of excitation spreading for the pulse velocity, proportional to T L .
Because of the lumped capacitance at the point X = 1 task should be divided into two parts: in the domain 0 < X < 1, and in 1 < X < 2.
Then the solutions should be substituted into equation (4) and from it was possible to determine the unknown function  (T). Solution of equation (1) in the domain 0 < X < 1 with the boundary conditions (2) and (6) and the initial condition (5) In domain 1 < X < 2 with boundary conditions (6) and (3) and the same initial condition we get (1) (4)  For further calculations one needed to know the type of function  0 (T), i.e. the change of working node potential in time. We approximated this dependence by a function where  2 -maximum capacity; T 1 -rise time capacity. Because of abovementioned reasons, the initial value of this function can be set equal to zero.
As follows from the experimental data according to [9], such approximation is not far from the truth. Substituting (7), (8) and (9)  All the roots of (11) are negative and layed to the left of n 2  2 . We denoted the found roots p 0 , p 1 , p 2 , ..., p k , ...
Knowing the poles of function, it is easy to do the inverse Laplace transform: The time of excitation "hopping" T L from one node to another is determined by condition that at time T = T L the node potential at point X = 1 should reach the threshold Because the true dimensional hopping time from one node to another is R 1 C 1 L 2 T L , and the distance between nodes L, then velocity of the pulse is As an example, lets compare with physical processes at the frog myelinized nerve fiber described in work [14]. In cases of some known spread values, we took the average value. So, we assumed that At the end of calculations lets study two cases: the front widths of the intervals were 1.5 and 2, i.e. when T 1 = 1,5T L and T 1 = 2T L . For the case T 1 = 1,5T L the calculation gave the speed v = 29 m/s. For T 1 = 2T L we obtained v = 21 m/s. From other side, the experimentally measured value of velocity is 23 m/s. So, close values in all these cases demonstrated good adequacy of performed and simulations as well.
2D modeling of matrix of bionic element in biotechnical system. Experimental study of the structure and function of neurons in the brain and other cells is an important area of brain research [15][16][17] including researches with fluorescent markers as well as biotechnology during the last decades. One interesting way of further carrying of such investigations is a construction of biotechnical systems where the technical part and biological one (implants, cultured samples etc.) were combined. Such combination have good prospects for their use for organism damage corrections, for disabled peoples cure, and etc.
Despite the fact that the experiments in this area of science are extremely laborintensive, high-tech and expensive, the number of Ukrainian researchers still keep them now in collaboration with foreign scientists [37][38][39][40]. Among Ukrainian researchers several research groups perform optical registration on the cells of various tissues and single cells [38][39][40]. All such studies have to be carried out under the control of luminescent, confocal microscopes using fluorescent markers, in our experiments -primulin and bis benzimid [15][16][17]. Tracking the processes during experiments performed the sets of digital pictures recorded in the computer memory. The sources of experimental data that were taken into account for modelings -electrophysiological experiments (patch-clamp, voltage clamp, and others [13,14]. Results of such experiments (9) (10) (14) were combined with optical ones in attempts to construct suggested 2D model -our observed biotechnical system. Briefly, the primary relative 2D physical model for this task was following. The samples of brain neurons were inquired into the observed biotechnical system as rectangular 2D plate with cultured brain neurons constructed as 2D matrix. Taking as the base the results of electrical and optical properties of natural studied brain neurons, we developed computer models for 2D neuronal matrix (biotechnical system) with properties of memory and symbols coding.
Physical and biochemical nature of 2D matrix from bionic elements. In base of original model (version of 2-dimentional network from brain neurons) experimental results described in our previous articles are put [15][16][17]. The sense of registered phenomena [17] was in the fact, that input signal changes of optical properties of the neuron (luminescence of neuron) become more intensive in case of neuron excitation. Other results that were taken into account during modeling were the results of transmembrane electric currents studying in experiments with patch-clamp, voltage-clamp, and etc. [13,14]. Basing on these facts the 2D matrix as our model was elaborated. This matrix may be imagined as an abstraction of one-layer cell culture where neurons are ordered as it was shown on Fig.  4; the signal could be transmitted from cell to cell. This abstract construction has to be incorporated into the electric circuit with measuring and information storage devices described in numerical manuals (Fig. 4). Such system was biotechnical-one, constructed using principles of bionics; some laboratories of the world reported about such constructions [1]. Developing program model, we based on abstract supposion of 2D neuron matrix existing. Schematically it is suggested below.
At the next step we would like to elaborate a program model of this neuronal matrix that was called "quasi screen" (Fig. 4) this abstract neurons there were ordered on 2D matrix. Simultaneously the screen pixels have been brought into compliance with these abstract neurons. All these stages of our investigations were done, and results were already published in different scientific and technical journals [15,16]. Further stages according to our plans were following: 1-simulation of 2D "quasiscreen" functioning (model 1), and elaboration of program for the simplest symbols coding at such screen (model 2). Obtained results were suggested below.
Description of a "quasi screen" with bionic elements for biotechnical system. Probable "quasi screen" with bionic elements for biotechnical system may be imagined as 2D neuron matrix on plastic plate with cultural brain neurons in dissociated culture incorporated into electric circle with standard measuring and data stored devices. 2D neuron matrix may be imagined as a model like chessboard with alternating rows and columns that separate the cells which contain optically active elements. The structure of such a screen we described previously in details [15]. For our model we assumed that in some cells of this screen there are bionic photosensitive elements [15].
Assumptions of the model. When designing a model, we made the following assumptions.
1) Each screen pix e l can be in 3 states, corresponding to 3 states of natural neuron (quiet, excited and refracter state of neuron). These 3 states were coded by "red", "yellow", "achromatic" colors respectively.
2) Also, a pixel could be described by threephase model. Natur e of these phases also corresponded to quiet, excited and refracter state of neuron.
3) The demonstrational velocity of the model has been increased 60 times: one minute of real processes in nature (as recorded in the experiment), corresponds to 1 second model. 4) Image coding it was possible to realize by establishing of different color points pattern in any set time interval.
As it was mentioned above, the lightsensitive elements of "quasi screen" were bionic elements with variable optical properties. According to our experiments these bionic elements may be following. 1) complex protein molecule and molecule optically active substance (fluorochrome); 2) "luminescent" neurons described in our article [17].
Our model was designed for the "screen" where optically active elements are the neurons with fluorochrome molecules inside. We have developed a model based on dynamic changes in the optical characteristics of the neurons that we described previously in [17]. Dynamics of optical neuron characteristics changes in screen matrices. According to the results of the experimental neuron reaction studying, the receipt of the excitation signal can be represented as three consecutive phases that have their physical, biochemical and physiological sense (Fig. 5).
Vectors mean transition of the system from one state to another. Vertices of the triangle are three states in which the system can be (Fig. 5). These three states on the model were colored with white, red and yellow colors. Respectively, -Top 1 corresponds to described phase 1 and 4 (achromatic).
This model 1 demonstrated the activity of "quasi screen" with neurons for the case when activated signal were inputted to active element at the left top of neuronal matrix and than moved to the right bottom angle. We supposed that each active element of the screen may be activated with further relaxation. Below we described these phases of activation and deactivation of each element.
2) The second phase of bionic element excitation was at time moment (t 1 ). The phase was depicted at Fig. 5 as point 2. Interval t 1 -t 0 =20 seconds. During system transition from the phase 1 to phase 2 the amplitude of activated signal -electrical current growed to the maximum А = А max . Pixel luminescence was maximal (E max ). At model the neurons of this phase were marked by red color (Fig. 4, 7, 8).
3) Additional points were characteristic (middle points) for the excitation of bionic elements at time moment ((t 2 , t 3 ) (depicted on Fig. 5 as point at vector between 2 and 3). Interval t 2 -t 0 = 30 seconds and time points near it. At these time points the amplitudes of activated signal (electrical currents) are going to decrease (bionic element luminescence is decreased) А = А min . Pixel luminescence decreased to minimal values (E min ). At model elements of this phase were marked by yellow and orange depending on current amplitudes and intensity of luminescense (Figs. 4, 7, 8).
4) The fourth phase of bionic element activation was at time moment t 4 . Interval t 4-t 0 = 180 seconds. The phase was characterized by signal amplitude (electric current) A = 0, luminescence intensity was going to zero (E 0 ). These elements were achromatic at model too (Fig. 6).
At the "screen" at Figs. 6-8 the bionic elements were depicted by the circles at defined positions on screen matrix. This arrangement of bionic screen elements was determined by conditions in which the existence of bionic elements is possible under the experimental conditions. The initial view of the model and the initial step of the program was shown at Fig. 6.
The next figure demonstrated the model at 101th second from process start. It was possible to see that one element might be at the second phase; some other elements were at phase number three, and so on.
At the last figure there were demonstrated the program work at 120 th second from process start. One can see here that all elements moved gradually, after specified period of time, from In developed original model of this biotechnical system two figures: triangle and circle can be coded. Systems which may be described in such ways potentially are the systems with "memory", if system can stay in some of states longer than in other states. Thus, the proposed model could be used for modeling the "screen" with elements that have properties of memory.
Model algorithm. Model described above was abstract and basic. Its algorithm was given on Fig. 9.
So, in such a way we tried to make a model of coupling between transmembrane electrical currents and their visualization using fluorescent drugs. Taking as the base the results of electrical and optical properties of natural brain neurons studying we develop computer models for 2D neuronal matrix (biotechnical system, "quasi screen") with properties of memory and possibilities of symbols coding. Program model of electrical signal propagation (and, respectively, information signal propagation) in this biotechnical system was elaborated.
3D model: mathematical model of estimation of hypoxia development in brain gliomas. As it was noted in our previous publication [1], the state of hypoxia in tissues (the brain in particular) can occur dye to the low oxygen concentration at altitudes, due to diseases or metabolic disorders, and etc. The development of tumors of the brainglioma -also leads to the development of hypoxic phenomena. The study of these phenomena were done by Prof. Onopchuk Yu.M. (Glushkov Instituite of Cybernetics, NAS of Ukraine, Kyiv) and researcher Guzhavskaya N.V. (Institute of Neurosurgery, NAS of Ukraine, Kyiv) [31].
Estimating the degree of tumor influence on organism, researches were faced a number of problems that they tried to solve by analyzing the clinical and laboratory data obtained during the patient examination. Based on these data, they would determine how much the initial loading caused by the tumor affects the patient life expectancy in the catamnesis, how to predict the possible time intervals of the tumor recurrence, the possibility of complications during the operation and in the early postoperative period. The process of tumor development in organism was considered as an stochastic one, although it is often preceded by functional changes in the organism, caused by the influence of adverse and extreme external environmental conditions, in which the vital activity of the organism was carried out. Therefore, the methods of the theory of reliability of complex systems were used to estimate the tumor pressure on the organism and the degree of risk to patient's health. Consequently, the refuse of the system from functioning is associated with the achievement of the load function S (t), which reflects the degree of tumor influence on organism, a certain boundary level S (t). Naturally, the effectiveness of conservative or surgical treatment can be estimated using the scale [0, S(t)]. First of all, let's observe the model of clinical data of patients with brain glioma. When a patient arrived to hospital for treatment, a number of clinical indices of his condition were determined. Among the most important were: the degree of malignancy of the tumor (indicator f 1 **), tumor localization (f 2 **), the presence of mediastinal structures of the brain displacement (f 3 **), the presence of perifocal edema (f 4 **), tumor density (f 5 **), the presence of cysts formation (f 6 **), the type of disease course (f 7 **), the severity of general brain symptomatic (f 8 **), the severity of the focal symptomatic (f 9 **), the severity of stagnation in fundus (f 10 **), the tumor's consistency (f 11 **), the connection of the tumor with main vessels (f 12 **). Most of these indices were determined by tomographic, laboratory and exclusive research.
The values of each of these functions (f i **, і=1,12), which significantly affected the condition of patient with brain gliomas of different degrees of malignancy. They determined the functional capabilities of organism in life processes realisation, and they can be called a discrete set. We can assume that this value ws equal to: 1, if gliomas of the first degree were detected, 2, with gliomas of the second degree, M (f 1 ** ) = 3, with ependymomes, gliomas of the third degree, 4, with gliomas of the fourth degree.
0 -vessels were immured in a tumor, M (f 12 ** ) = 1 -main vessels did not belong to the tumor, 3 -main vessels were loosely soldered. The influence of tumor on human organism studied only through clinical parameters, could be estimated by a linearly weighted function: (1) where  i were coefficients of importance of some indices in the system of organism estimation, which could be determined as a result of factor analysis of the data. In general,  i was taken into account during the construction of the sets M (f i , і=1,12), and therefore in the simplest case we could assume that F cl =  f i cl (2) Models of laboratory data of patients with brain glioma. The development of a malignant tumor of different nosology required the strengthening of the circulatory system functions in places of tumor localization, which supplied oxygen to the cells of the brain, enzymes and other essential substances for vital activity. Therefore, for the estimation of the degree of tumor influence on the systemic states of the organism, it was necessary to take into account the parameters of laboratory examinations of patients. In the practice of neurosurgical clinics among the most important laboratory indices were: f 1 * -severity of hemoglobin content in blood, f 2 * -severity of leukocyte contents in blood, and complex influence of clinical and laboratory indices: Thus, when determining the limiting value of the tumor load on human organism using the linear regression equation (4), we used the clinical and laboratory data of the patients of the neurosurgical clinic. The analysis of estimations of loading demonstrated that after the reaching of the limit value S, equal to 18 points, 421 patients (58%) had a life expectancy of about 3 years in catamnesis. 300 people have lived less than 3 yearsthe loading of their tumor was less than 18 points. Statistical data analysis demonstrates that obtained data were reliable (P < 0.01). For people who lived in catamnesis up to 15 months, the average tumor loading was 18.03 ± 0.05 points, from 15 months to 3 years -18.15 ± 0.12 points, from 3 years to 5 years -17.07 ± 0.03 points, and more than 5 years -16.04 ± 0.02 points. Thus, an essential correlation of value of tumor loading with the duration of life in the catamnesis was found (Fig. 10).
For patients with relapses of disease in catamnesis up to 15 months, the average tumor load was set at 18,18 ± 0,1 point (IV), from 15 months to 3 years -18,17 ± 0.06 points (III), from 3 years up to 5 years -16.17 ± 0.3 points, more than 5 years -17.6 ± 0.42 points. For patients with relapses of the disease in catamnesis, 179 people (56%) had a load of more than 18 points, 139 people (44%) -below 18 points. The differences were statistically significant (P < 0.05). Thus, it can be argued that value of tumor load on organism, found basing on clinical and laboratory data of patient in hospital, substantially influences on the possibility of tumor relapses. The calculation of tumor load on organism according to formulas above demonstrates that patients with a load of 19.48 ± 0.2 points had complications during the surgical operation; the load of patients Clinical and laboratory data of patients examination in the early postoperative period gave a possibility to found that complications in this period had patients whose load in the preoperative period was 18.74 ± 0.06 points, while for patients without complications -17.35 ± 0.04 points . It should be noted that among patients with a load above 18 points, 39% had no complications in the postoperative period. The average load of the tumor on organism depending on the group of glioma demonstrated that at stage I of malignancy the average load was set at the level of 14.9 points, at the stage II -16.14 points, at stage III -18.75 points, and at stage IV -19.08 points (Fig. 11).
The analysis of the data obtained using linear regression about the value of tumor load on organism demonstrated a high correlation with the Karnovsky index, which is used for the estimation of disease severity (Table).
Thus, the use of linear regression method for the processing of clinical and laboratory data of patients with brain gliomas allowed us to determine the limit value (18 points) of the tumor load on organism; and in each case of the disease permitted to plan an individual strategy for patient treatment.
Thus, in present publication the analysis of some ways of modeling methods development for biotechnology according to contemporary achievements in science and technique was done. At the beginning of this article the general approaches were demonstrated, some types of classifications of modeling methods were observed. Previously we outlined some types of mathematic analysis widely used for modeling purposes: factor, dispersion, correlation, discriminant ones; as well as methods of classification, other methods of statistical data processing. Special attention it was necessary to pay to such powerful mathematical methods used in biotechnology as neural networks, cluster analysis, and image processing. The role of mathematic methods modeling for biotechnology in present époque of information computer technologies intensive development was studied and appropriate scheme of interrelation of all these spheres was suggested. Further in our article some case studies are given; as well as some mathematic models developed for processes in living objects of different levels of hierarchic organization. Actually, the models for objects of 1D, 2D, 3D cases were suggested. In course of this the main attention was paid to some processes modeling in neurons as well as in their aggregates of different forms, including glioma of the brain. Starting from the models that have only theoretical importance for today, we suggested 1D and 2D models for some processes at neurons. In 2D model of neuronal matrix we tried to make a model of coupling between chemosensitive transmembrane electrical currents and their visualization using fluorescent drugs taking as the base the results of electrical and optical properties of natural brain neurons studying. Program model of signal propagation and symbols coding in this biotechnical system was done as well.
In present article we outlined modeling techniques to simulate neuronal processes not for single neurons or their 2D networks and systems only. As an example of 3D modeling we suggested the model of glioma with its analysis; this work we see as extremely important for the practice. Such analysis of the data obtained using linear regression about the value of tumor load on organism demonstrated a high correlation with the Karnovsky index, which is used for the estimation of disease severity. So, the use of linear regression method for the processing of clinical and laboratory data of patients with brain gliomas allowed the authors of this model to determine the limit value (18 points) of the tumor load on organism and in each case of the disease permitted to plan individual strategy for patient treatment.