Activation of HERV-K(HML-2) disrupts cortical patterning and neuronal differentiation by increasing NTRK3.

The biological function and disease association of human endogenous retroviruses (HERVs) are largely elusive. HERV-K(HML-2) has been associated with neurotoxicity, but there is no clear understanding of its role or mechanistic basis. We addressed the physiological functions of HERV-K(HML-2) in neuronal differentiation using CRISPR engineering to activate or repress its expression levels in a human-pluripotent-stem-cell-based system.

[An aggregation method for determination of parameters of mathematical models].

Two mathematical models for calculation of the probability of post-radiation complications in normal tissues are considered. The first model provides calculation of the probability of post-radiation complications within the entire dose and tissue volume range. The second model is approximative.

[Methods for geometric and nonlinear optimization of the structure of interstitial implants for interstitial x-ray therapy of malignant tumors].

In 1990 G. K. Edmundson suggested a geometric optimization method for determination of the effective structure of interstitial implants.

[An interactive method for optimization of irradiation plans in radiation therapy of malignant tumors].

Formation of a rational dose filed in contact radiation therapy of malignant tumors is, in the majority of cases, a multicriterion and multiextremal problem. A compromise plan of irradiation can be obtained by interactive matching of alternative criteria of radiation therapy. In this work, it is suggested to solve the problem of formation of effective therapeutic dose fields using synthesized methods, including modified trial-and-error method (visual optimization method), and mathematical programming methods.

[Synthesis of radiological models and radiological constants. Part 4: Synthesis of population-phenomenological models and Lyman model].

The goal of this work was to synthesize Lyman mathematical models (MM), which describe the probability of post-radiation complications (PRC) in tissue subjected to radiation therapy with given scheme of dose fractionating (DF), and population-phenomenological (PP) MMs PP3 and PP4, which describe equivalent DF schemes for a fixed PRC value. Construction of synthesized MMs (SMMs) becomes possible only on the basis of several assumptions requiring further clinical validation. Synthesized MMs can be used for determination of the optimal dynamic conditions of irradiation of malignant tumors.

[Synthesis of radiological models and radiological invariants (constants). (Part 3: synthesis of population-phenomenological models and Klepper model)].

The goal of this work was to synthesize Klepper mathematical models (MM), which describes the probability of post-radiation complications (PRC) in tissue subjected to radiation therapy with given scheme of dose fractionating (DF), and population-phenomenological (PP) MMs PP3 and PP4, which describe equivalent DF schemes for a fixed PRC value. Construction of synthesized MMs (SMMs) becomes possible only on the basis of several assumptions requiring further clinical validation. Synthesized MMs can be used for determination of the optimal dynamic conditions of irradiation of malignant tumors.

[Synthesis of radiological models and radiological invariants (constants). Part 2].

The goal of this work was to synthesize a mathematical model (MM) on the basis of Klepper and Lyman MMs, which describe the probability of post-radiation complications (PRC) in tissue subjected to radiation therapy with given scheme of dose fractionating (DF), and the LQ-model, which describes equivalent DF schemes for a fixed PRC value. Construction of synthesized MMs (SMMs) becomes possible only on the basis of several assumptions requiring further clinical validation. Synthesized MMs can be used for determination of the optimal dynamic conditions of irradiation of malignant tumors.

[Multiple fibromas in systemic mastocytosis].

An adult man with systemic mastocytosis developed multiple fibromas within his involved skin, predominantly in the intertriginous areas. Friction in the intertriginous areas and scratching due to severe itch may have induced the release of mast cell factors which subsequently resulted in fibroma formation.

[Interactive input and correction of data about the structure of irradiated organism in the planning of radiotherapy for malignant tumor].

A method is suggested for the interactive input, conversion and presentation of data about the structure of irradiated organism preset as Data Reference Planes (DRP). The possibility to build a library of DRP and the simplicity of their adjustment to each disease case witness to that the method of input, storage, conversion and presentation of data about the irradiated organism is promising in tumor radiotherapy.

[Estimated equivalent radiation conditions (EERC), more useful clinical data and estimation of potential resorption of lesion nodule with respect to its volume and total focal dose].

Assumptions on properties of tumor cells are defined. On the basis on them the survival rate of tumor cells is described by the LQ function and the dependence of resorption probability (RP) in the lesion nodule on the number survived tumor cells (tumor volume) and on the total focal dose (TFD) is described by the Poisson function. An analysis of the above approach to the determination of lesion-nodule RP resulted in designing a calculation method for EERC that can be used to estimate the lesion-nodule RP as a function of its volume and TFD.

Localization of binding sites of naturally occurring antisperm antibodies on human spermatozoa by immunofluorescence.

Antisperm antibodies (ASA) may affect sperm motility, acrosome reaction, sperm penetration of cervical mucus, binding to the zona pellucida, and sperm-egg fusion. We investigated the localization of ASA of infertile men or men after vasectomy bound on the sperm surface using an immunofluorescence method. Binding occurred in the acrosomal region, midpiece, and tail.

[Mathematical modeling of optimal dose fields in radiotherapy of malignant tumors. Part 2 (Contact methods of radiotherapy)].

The principles of mathematical modeling of optimal dose fields in contact radiotherapy (RT) of malignant tumors are investigated. The point dose additivity provides for presetting the permissible dose field in an irradiated organism as a system of linear limitations to doses in the control points (CP) distributed in the lesion focus and in healthy organs and tissues. It was shown as impossible to shape a dose field by linear limitations to doses in CP in using the RT contact methods with the irradiation sources being implanted into lesion focus.

[The mathematical modeling of the optimal dose fields in radiation therapy of malignant tumors. Part 1 (Distance radiotherapy)].

The specificity of mathematical modeling of optimal dose fields in radiation therapy of malignant tumors is under consideration. The permissible dose field is set now for irradiated body as a system of linear limitations to the doses at control spots (CS) distributed in the lesion focus and in the healthy organs and tissues. It is for the first time that an issue related with choosing an adequate number and method of CS distribution, based on uniform continuity of the dose field, is addressed in the paper.

[A method of the interactive visual optimization of the therapeutic dose field in contact radiation therapy of malignant tumors (theoretical aspects of the problem)].

The mathematical and interpretation tasks of a directed shaping of dose fields in the contrast radiation therapy of malignant tumors are defined on the basis of the dose-field homogeneity parameter. A schematic iterative algorithm of how to solve the tasks is described. A method for the visual optimization of such field is elaborated; it is based on preset limits to the dose field in the lesion focus and in the healthy organs and tissues.

[Shaping-up of optimal dose fields in a stretch by means of dot-type and linear sources of irradiation (theoretical aspects)].

Shaping-up of a dose field in a stretch by means of dot-type and linear irradiation sources is mathematically interpreted. A criterion of an optimal dose field is formulated for the contact radiotherapy applicable to malignant tumors, which is based on homogeneity of such therapy. The task of forming an optimal dose field in a stretch by the dot-type and linear irradiation sources is insoluble on the basis of analytical methods.

[Formation of optimum dose fields in contact radiation therapy of malignant tumors].

The definition of the homogeneity of a dose field in the contact radiation therapy for malignant tumors is introduced. The mathematical interpretation of problems in the formation of optimum dose fields, to which the maximum homogeneity of a dose field at the site of lesion corresponds, is presented. It is shown that the problems in the formation of optimum dose fields may be divided into two subsets in relation to whether the sources of radiation are located at the site of lesion or adjacent to the latter (application techniques of radiation).

[A summarized method for calculating the possibility of resorption of a focal lesion as a function of its volume and irradiation dose].

The mathematical model of calculation of equivalent conditions of irradiation (CECI) can be used in those cases, when it is impossible to divide clearly the tumor cells into radiation sensitive (RS) and radiation resistant (RR) and when the spectrum of radio-biological properties of tumor cells can be regarded as quasi-continuous.

[Approximate methods for calculation of the likelihood of radiation complications. The generalized PKLQ method (GPKLQM)].

Search for rational schedules of radiation therapy for malignant tumors is a topical problem of modern radiology. It cannot be solved without prognostic estimates of radiation affecting tumor and normal organs and tissues. The aim of the study was to develop mathematical models to be used for approximate evaluation of radiation affecting a tumor focus and normal organs and tissues.

[Approximate methods for calculating the probability of radiation complications. The PKLQ method].

A method of approximate calculation of the probability of resorption of a lesion focus by means of three mathematical models: the Poisson model, the Klepper model, and the LQ-model (the PKLQ method) is described. The method is based on a procedure for reducing SOD to the preset scope of a lesion focus. It is suggested that radio-sensitive (RS) cells predominate in the focus of lesion; radio-resistant cells are available in small quantities or their radiobiological properties differ from RS cells.

[Approximate methods for calculation of the likelihood of radiation-induced complications. 1. ACLRC method. 2. CERC method].

The paper deals with the method of approximate calculation of the likelihood of radiation complication (ACLRC) in normal organs and tissues when the volume of information is insufficient to determine all the parameters of a mathematical model. How to use the approximate method of LRC in the heart is exemplified. A method for approximate calculation of equivalent radiation conditions (CERC) in the focus of a lesion is offered, which allows the preset analytical (or graphic) description of the relationship of resorption likelihood (RL) to SOD for the fixed volume of a lesion focus to be transferred to the description of this relationship for other volumes.

[Probability of tissue cell death, integral cellularity and likelihood of radiation-induced tissue complications].

The paper describes a mathematical model for determining the likelihood of radiation-induced complications in the tissue as a function of the number of surviving cells. It is suggested the irradiated tissue cannot be regarded as a structureless point set of cells and that there are repairable and nonrepairable spatial configurations formed by surviving tissue cells. The probability of none tissue radiation complications may be considered is that of formation of a repairable structure from the surviving tissue cells.

[Method of calculating the equivalent tumor dose as a function as to irradiated tumor tissue volume].

Based on the assumption that tumor tissue consists of normal and radiation-resistant, that the survival of both types of tumor cells may be described by LQ functions and that the count of radiation-resistant cells is in proportion to that of tumor cells, the author has developed a method for calculating the equivalent tumor dose as a function as to irradiated tumor tissue volume for the fixed value of a single dose in the session of radiation. The developed formalism may be used to test the hypothesis that the count of clonogenic and radiation-resistant cells is in proportion to the baseline number of the cells in the tumor tissue.