[Interaction of proteins with platinum and palladium compounds with differing biological activities]. / Vzaimodeistvie belkov s soedineniiami platiny i palladiia, obladaiushchimi razlichnoi biologicheskoi aktivnost'iu.

Protein interaction with bioactive platinum and palladium complex compounds was studied by solid-phase sorbent assay (SSA), turbidimetry, isoelectric focusing and circular dichroism. In SSA reaction ability of metal compounds can be represented as follows: [equation: see text] Reaction ability of proteins can be represented as follows: hemoglobin > serum albumin > immunoglobulin. The reaction products of serum albumin and metal compounds demonstrated more alkaline isoelectric points then the intact albumin resulting from adding positively charged metal centers [MeCl+, Me2+, [Me(H2O)n]2+, [Me(H2O)nCl]+ to albumin molecules. In metal-protein complexes circular dichroism demonstrated the diminution of alpha-helix structure percentage if compared with intact albumin, the most prominent effect being caused by K2[PdCl]4. The conformational distortion of albumin was significant. Metal compounds mostly affected the optical activity of S-S-protein bands (251-254 nm). Experimental evidence confirmed the hypothesis that platinum metal complexes with high reaction ability are less toxic than those with low reaction ability.

[Immunoglobin-binding proteins in human placenta]. / Immunoglobulin-sviazyvaiushchie belki platsenty cheloveka.

Phenomena of the binding of poor-soluble placenta proteins (PSPP) with pregnant women sera IgG as well as placenta blood IgG were studied. PSPP were extracted from the placenta tissue, washed out from soluble proteins, by the use of 3M KCl solution containing 0.005 M PMSF. PSPP were separated by the use of two-dimensional isoelectrofocusing and SDS-PAG electrophoresis and more than 30 different polypeptides were visualized. Having used various ELISA procedures with pregnant women sera IgG, placenta blood IgG as well as its Fab and Fc-fragments we have shown that both the receptor-type and the antigen-antibody-like interaction of PSPP took place. Both the polypeptide compositions and the isoelectrofocusing points ranges of the antigen-antibody-like interacting IgG-binding PSPP were determined by the use of the peroxidase conjugated Fab-fragments of the placenta blood IgG.

[A method of solid phase immunoenzyme analysis using antigen molecules immobilized on membranes]. / Metod tverdofaznogo immunofermentnogo analiza s ispol'zovaniem immobilizovannykh na membranakh molekul antigena.

The enzyme-linked immunoassay modification has been worked out. The method combines advantages of membrane technology of antigen immobilization which is used in the enzyme immunosensory technique and of conventional enzyme-linked immunosorbent assay. The nitrocellulose and polypropylene membranes are used as a solid-phase. The purified rabbit immunoglobulin G is immobilized on the surface of membranes as the first layer. The competitive immunoassay is employed. The immunoglobulin G concentration range is 1-1000 ng/ml. The membranes with the immobilized antigen can be repeatedly used after incubation in 0.1 M glycine buffer, pH 2.5. The dry membrane with the immobilized antigen can be used after keeping for 6 months in refrigerator at 4 degrees C without changing the concentration range measured.

[Activity of the natural killer cells in the peripheral blood of patients with brain tumors]. / Aktivnost' estestvennykh killernykh kletok perifericheskoi krovi bol'nykh s opukholiami golovnogo mozga.

Activity of natural killer cells (NK-cells) was determined in a 4-hour 51Cr-release test using K-562 as target cells in patients with brain tumours and donors. This activity was significantly (P less than 0.05) reduced in preoperative patients with metastatic brain tumours (mean--5.7%), gliomas of III-IV malignancy grades (mean--16.4%) as compared with the control (mean--32.5%). The activity of NK-cells remained low after surgical treatment irrespective of the length of remission.

[Proliferative activity of experimental brain tumors]. / Proliferativnaia aktivnost' éksperimental'nykh opukholei mozga.

The method of autoradiography was used to study the parameters of the cell cycle and the intensity of proliferative processes in three transplantable rat brain tumors differing in the duration of the latent period and sensitivity to chemotherapy. The tumors were found to be similar in the duration of the cell cycle and its phases, the mean values of the label index and growth fraction, and were characterized by the irregularity of the proliferative processes within the tumor; the label index was higher in the center of the tumors (threefold in one case) than in the zone of their growth. It is suggested that the sensitivity of brain tumors to chemotherapy does not depend on their cell kinetics.

[Neurospecific proteins: potentials and prospects for their use in morphological research on tumors]. / Neirospetsificheskie belki: vozmozhnosti i perspektivy primeneniia v morfologicheskom issledovanii opukholei.

Data on the application of neurospecific proteins S-100, GFAP, D2 glycoprotein and neuron-specific enolase (NSE) in the differential tumor diagnosis are reviewed. S-100 protein and GFAP are found in well differentiated astroglial tumors. S-100 protein can be used as melanoma and Schwannoma specific marker. In malignant CNS tumors there is a decrease of S-100 protein content up to its complete disappearance, while the content of GFAP is variable. D2 glycoprotein is detected in gliomas and medulloblastomas, being absent in other brain tumors. NSE is invariably present in apudomas and was also found in the majority of investigated astrocytomas, ependymomas, glioblastomas and in some medulloblastomas.

[Characteristics of specific intermediate filament proteins in human brain tumors]. / Kharakteristika spetsificheskikh belkov promezhutochnykh filamentov v opukholiakh golovnogo mozga cheloveka.

The content of glial fibrillary acidic protein (GFAP) was measured in human brain tumours with different histological structure, origin and rate of malignancy. The polypeptide composition of CFAP was established in human brain and tumours by SDS polyacrylamide gel electrophoresis followed by immunoblotting. In tumours with an astrocyte type of differentiation, GFAP was revealed as a set of immunologically related and partially degraded polypeptides with a molecular weight of around and below 37 kD. It was assumed that the appearance of intact GFAP polypeptides (49 kD) in some tumours may be considered as a result of penetration of reactive astrocytes into tumour tissue.

[Formation of superoxide radicals by the nuclear membranes of human brain tumors]. / Obrazovanie superoksidnykh radikalov iadernymi membranami opukholei mozga cheloveka.

It has been discovered that nuclear membranes isolated from human brain tumors are capable of cyanide-sensitive oxidation of adrenaline to adrenochrome in the presence of both NAD X H and NADP X H while the process of oxidation is inhibited by superoxide dismutase. At the same time nuclear membranes isolated from the brain tissue do not oxidize adrenaline to adrenochrome in the presence of both substrates. A possible relationship between the properties of the nuclear membranes and the degree of tumor malignancy is discussed.

[Immunologic sensitization to tumor-associated antigens during the growth of gliomas of the brain (experimental study)]. / Immunologicheskaia sensibilizatsiia k opukholeassotsiirovannym antigenam v dinamike razvitiia gliom golovnogo mozga (éksperimental'noe issledovanie).

The reactions of cellular immunity to malignant gliomas of the rat brain were studied by measuring the electrophoretic mobility of indicator cells (the EPM test). The appearance of sensitization coincided in time with the development of the glioma's own vascular network possessing no barrier function. The sensitization was constant in character and persisted till the death of the tumor-carriers. The EPM test did not reveal qualitative differences in sensitization in intracerebral and subcutaneous glioma growth.

[Ultrastructural organization of methylnitrosourea-induced brain tumors in the rat. Serial transplantation]. / Ul'trastrukturnaia organizatsiia opukholei mozga krys, indutsirovannykh metilnitrozomochevinoi. Issledovanie v protsesse passirovaniia.

The specific ultrastructural features of two transplantable rat gliomas (221 and 223) are described. The tumors contained poorly differentiated anaplastic cells and differentiated cells with a great amount of gliofibrils. The resemblance of experimental gliomas to human gliomas is discussed. The capillary ultrastructure in the transplantable gliomas is described.

[The role of the system of superoxide radical formation and detoxication in the mechanism of the antineoplastic effect of adriamycin]. / Rol' sistemy obrazovaniia i detoksikatsii superoksidnykh radikalov v mekhanizme protivoopukholevogo éffekta adriamitsina.

The intensity of formation of superoxide radicals (O(-2)) and superoxide dismutase (SOD) activity in the tissue of two transplantable gliomas were examined. The cells of these tumors were marked by unbalance between the intensity of O(-2) formation by nuclear membranes and their detoxication of SOD. This unbalance was particularly demonstrable in glioma 35 which was marked by rapid growth and high sensitivity to adriamycin. Slow-growing glioma was noted for higher activity of SOD and was insensitive to adriamycin. Since it is known that anthracycline antibiotics raise the intensity of the formation of free oxygen radicals in tumor cells, the data obtained suggest that the intensity of formation and detoxication of O(-2) may be used for the assessment of the sensitivity to these drugs.

[Experimental study of the antitumor activity of nitrosomethylurea, adriablastine and ftorafur on model gliomas with different growth rates]. / Eksperimental'noe issledovanie protivoopukholevoi aktivnosti nitrozometilmocheviny, adriablastina i ftorafura na modeli gliom s razlichnoi skorost'iu rosta.

A marked antitumor effect of the agents studied was demonstrated in experiments on three strains of gliomas of the brain of rats (two rapidly-growing and one slowly-growing tumor). Phthorafur increased the survival of the animals with one of the rapidly-growing tumors (strain No. 35) and often had a marked side effect. Adriablastin inhibited the development of rapidly-growing gliomas but was ineffective in experiments with slowly-growing glioma. NMU considerably increased the survival of the animals in all experiments but recovery was not encountered. In treatment with NMU, a cell population resistant to this agent occurred in the gliomas. A new glioma strain was obtained during the experiments; it was insensitive to therapeutic doses of NMU and differed in morphology from the initial highly-sensitive tumor (strain No. 2211). The prospects of using agents of the nitrosomethyl urea group in the chemotherapy of gliomas are discussed.

[Brain tumors in the rat induced by methylnitrosourea (induction, transplantation, monolayer cultivation)]. / Opukholi mozga krys, indutsirovannye metilnitrozomochevinoi (induktsiia, transplantatsiia, kul'tivirovanie v monosloe).

Tumors induced in rats by chronic methylnitrosourea administration are described. Two strains of transplantable brain gliomas obtained by serial intracerebral transplantation of primary neoplasms and their monolayer cultures are characterized. These tumors were similar to human malignant gliomas in morphological and biological properties. They possesses high oncogenicity and are easily cultured in a monolayer, which allows their application in oncological and biochemical studies.