[Preoperative portal vein embolization: dynamics of portal pressure].

The pressure dynamics was studied in a portal vein (PV) in patients, suffering focal hepatic pathology, to whom portal vein embolization (PVE) was performed as a stage of preparation to radical hepatic resection. In 236 patients the immediate measurement of pressure in a PV was performed intraoperatively before and after PVE, in 26 - catheter for control portography and monitoring of pressure in a PV was left in its trunk for 24 h postoperatively. There was noted a pressure rising in a PV immediately after its embolization by 86.7%, positive correlation was established between PVE volume and pressure gradient in a PV before and after it. While doing monitoring during 24 h there was observed the pressure rising in a PV during 3 h after its embolization with subsequent lowering down to initial. Application of PVE as a preparation procedure for performance of extended hepatic resection, together with enhancement of residual liver minimizes sharp postresectional pressure rising in PV, what constitutes essential factor of the hepatocytes damage of residual hepatic part in immediate postoperative period.

[Results of preoperative embolization of portal vein in patients with biliary hepatic tumors].

The results of preoperative embolization of portal vein (EPV) in 90 patients, operated on for biliary hepatic tumors, were analyzed. In 47 patients Klatskin tumor was revealed, in 29--peripheral cholangiocarcinoma, in 14--tumor of a gallbladder. In all the patients a radical major hepatic resection was planned, a checking hepatic volume (CHHV) did not exceed 40% of a noninvolved parenchyma. The EPV volume have corresponded generally to the planned resection volume. After performance of EPV a pressure in a portal vein have risen by 75%, and later it have had lowered step by step during 24 h. The CHHV index have raised from (354 +/- 72) up to (462 +/- 118) cm3, or from (33 +/- 7) up to (45 +/- 11)%, permitting to perform radical hepatic resection in 79 (87.8%) patients. Thus, application of EPV in patients, suffering biliary hepatic tumors, have permitted to increase the CHHV index after radical resection, and to raise resectability of such tumors.

[Antibacterial therapy in surgical treatment of chronic hepatic abscess].

The results of surgical treatment of 58 patients for chronic hepatic abscess were presented. In patients of the main group hepatic resection was performed and in a control one--sanation and drainage of the abscess cavity. Antibacterial therapy was conducted in patients of both groups before and after operative treatment. The peculiarities and common efficacy of antibacterial therapy depending on the operative treatment kind were noted.

Metastasis of mammary carcinomas in GRS/A hybrid mice transgenic for the mts1 gene.

Transgenic mice, carrying the mts1 gene, one of the genes involved in the acquisition of the metastatic phenotype, were generated. The mts1 gene was placed under the control of the mouse mammary tumor virus (MMTV) long terminal repeat (LTR) promoter leading to overexpression in the lactating mammary gland of transgenic animals. Animals bearing the transgene appear phenotypically normal. Animals of two transgenic lines (Tg463 and Tg507) were crossed with the GRS/A mice. The GRS/A strain is characterized by high incidence of mammary tumors which rarely metastasize. 40% of the tumor bearing hybrid GRS/A mts1 females were found to develop secondary tumors in the lungs. The Mts1 protein was detected in the transgene primary tumor cells as well as in the corresponding metastases. Nontransgenic littermates expressed the Mts1 protein only in the stromal cells surrounding the tumor but not in the tumor cells by itself. Taken together these observations indicate that overexpression of the mts1 gene in the mouse mammary carcinoma cells gives rise to more aggressive tumors which are able to metastasize.

[Expression of a splice-variant of the mts1 gene in normal and tumorous human tissue]. / Ekspressiia splais-variantov gena mts1 v normal'nykh i opukholevykh tkaniakh cheloveka.

Data on cloning of cDNA corresponding to human mts1 gene transcripts are presented. By comparing nucleotide sequences of the genomic DNA clone and cDNA of mts1, it was shown that human osteosarcoma OHS cells contain two alternative splice variants of mts1 transcripts. Alternative splicing occurs in the 5'-untranslated region of the mts1 pre-mRNA. Both splice variants, hu-mts1 and hu-mts1(var), demonstrate similar stability in the cells, and each contains one open reading frame for the MTS1 protein. However, the two types of transcripts are translated with different effectiveness. The level of transcription of mts1 splice variants in different normal and neoplastic tissues and cell lines varies significantly. The role of alternative splicing as the mechanism responsible for posttranscriptional regulation of mts1 gene expression is discussed.

Non-muscle myosin heavy chain as a possible target for protein encoded by metastasis-related mts-1 gene.

The mts-1 gene is associated with the expression of the metastatic phenotype of tumor cells. The protein product of the mts-1 gene belongs to the S100 family of Ca(2+)-binding proteins with unknown biochemical function. In the present work, monoclonal anti-Mts-1 antibodies were used to isolate and characterize Mts-1 protein possible targets. Mts-1 protein can be immunoprecipitated by both anti-Mts-1 and anti-myosin antibodies as a complex with myosin from lysates of different mouse and human cell lines. Precipitation of myosin by anti-Mts-1 antibodies is specific and depends on the presence of Mts-1 protein. Ca(2+)-dependent association between Mts-1 protein and the heavy chain of non-muscle myosin was demonstrated by blot overlay technique. Furthermore, association between myosin and Mts-1 was confirmed by sucrose gradient analysis. Finally, immunofluorescent staining of the mouse mammary adenocarcinoma cell line showed that Mts-1 protein is co-localized with the myosin complex. The data suggest that the target for Mts-1 protein is a heavy chain of non-muscle myosin.

The mts1 gene and control of tumor metastasis.

The main stream of biology today is the analysis of the molecular mechanisms of major biological phenomena through studies of the genes governing these processes and their protein products. An example is the problem of tumor metastasis which is extremely important both theoretically and practically. Here we describe the data obtained on the detection, cloning, structure and transcription control of the mts1 gene, that encodes metastasin 1, a protein which seems to play an important role in the control of metastasis in mouse tumors. In particular, the experiments on tumor cell transfection with constructions containing either a sense or antisense mts1 sequence under a strong promoter/enhancer element show the direct dependence of the metastatic phenotype on the expression of the mts1 gene at least in some systems. Gene mts1 encodes a protein belonging to the family of Ca(2+)-binding proteins and may be involved in the control of cell motility in different types of cells, such as macrophages and T-lymphocytes. The relationship between mts1 and other genes up- and down-regulated in metastatic cells is discussed.

[Characteristics of a positive regulatory element in the first intron of the mts1 gene]. / Kharkteristika pozitivnogo reguliatornogo élementa v pervom introne gena mts1.

The first intron of the mts1 gene, a gene which is selectively expressed in metastatic cells and in normal cells that are motile, was found to be highly homologous to the CD3 delta enhancer element. Because of the homology between the CD3 delta enhancer and the first intron of mts1, we analysed the first intron of the mts1 gene to determine whether it functions as a transcriptional regulatory element. Highly metastatic CSML-0 cells transfected with chloramphenicol acetyltransferase containing plasmids demonstrated the ability of the mts1 first intron to function as a positive regulatory element. In vitro footprinting analysis using extracts from CSML-0 cells (which express mts1 at low levels) of CSML-100 cells (which express mts1 at high levels) identified a protected 16 nucleotide element in the first intron of mts1, regardless of the extract used. However, in vivo footprinting analysis of the same region identified the protected 16 nucleotide fragment only in the mts1 intron from CSML-100 cells, not from CSML-0 cells. Differences in the methylation pattern of the mts1 gene in CSML-100 cells and CSML-0 cells are known to exist, and may in part be responsible for the mts1 footprinting differences observed in vivo from the different cells lines.

[Structural and functional analysis of the promoter region of the mts1 gene]. / Struktunyi i funktsional'nyi analiz promotornoi oblasti gena mts1.

The mts1 gene is specifically expressed in metastatic tumors but not in non-metastatic counterparts. The gene was cloned from both mouse and human sources. The 5'-flanking regions of the mts1 gene from both sources were sequenced, revealing a 135 base pair region of high homology in the vicinity of the TATA box. The 5' region of the mts1 gene was also observed to have high degree of homology with some known promoter and enhancer sequences. The results of our transient transfection assays, in conjunction with those obtained from in vivo and in vitro footprinting of the promoter region, show no evidence of cis-control elements important for transcriptional regulation of mts1 gene. mts1 was found to be hypermethylated in CSML-0 cells and in the tissue types that do not express the gene or do that only at low levels. The possible role of methylation in progression of the nonmetastatic CSML-0 adenosarcoma cell line towards the metastatic CSML-100 adenosarcoma cell line will be discussed.

[The enzymatic chemical mechanisms of adaptation]. / K voprosu o nekotorykh énzimokhimicheskikh mekhanizmakh adaptatsii.

In sheep from biogeochemical provinces enriched by molybdenum and copper and in a model form of molybdenum toxicosis in animals, the important role of enzymic and neurohumoral systems in the development of adaptation to excessive uptake of molybdenum and copper has been demonstrated. Adaptive reorganization of the activity of enzymic systems (xanthine oxidase, ceruloplasmin, succinate dehydrogenase, aspartate and alanine aminotransferases) and gradual involvement of neurohumoral mechanisms of the sympathoadrenal and cholinoreactive systems provide for adaptation of some animals in molybdenum and copper-molybdenum biogeochemical provinces. In other sheep, under the same conditions, dystonic disturbances in the vegetative nervous systems are observed together with the development of molybdenum toxicosis.

Structure of gene mts1, transcribed in metastatic mouse tumor cells.

Different oncogenes are implicated in the genesis of tumors. However, little is known so far about the genes which are activated at the latest stages of tumor progression. While studying two genetically related mouse lines, highly metastatic CSML-100 and nearly nonmetastatic CSML-0, we have cloned the cDNA of the gene, mts1, which is specifically expressed in different metastatic cells. The gene contains an open reading frame of 101 amino acids and shows homology with a family of Ca2(+)-binding proteins. Here, we present data on the structure of a 17-kb genomic clone of mts1 with surrounding sequences. The gene contains two introns and three exons. The mts1 upstream region has been cloned in a plasmid containing the cat gene. The results of transient expression of the mts1-cat plasmid in NIH3T3 cells indicate the presence of a transcription regulator of mts1.

[Structure of the mts271 gene, coding a new calcium-binding protein]. / Struktura gena mts271, kodiruiushchego novyi, kal'tsii- sviazyvaiushchii belok.

A genomic copy of the mts271 gene which is specifically expressed in metastatic cells has been cloned and characterized. The gene consists of two exons and one intron and has an open-reading frame for the protein of 101 amino acids. The protein contains two helix-loop-helix calcium-binding domains, which is a common feature for the members of the large family of intracellular calcium-binding proteins (Ca B Ps). The primary structures of the mts271 gene products and other Ca B Ps were compared. High level of homology was found for S100 and calcium-binding protein of intestinal epithelium of rats. On the whole, the mts271 protein is a new calcium-binding protein which is specifically expressed in metastatic cells.

[Study of transcription of the DNA sequence of a mts271 clone in various tumor and normal mouse cells]. / Issledovanie transcriptsii posledovatelnostei DNK klona mts271 v razlichnykh opukholevykh i normal'nykh kletkakh myshi.

Transcription of the mts271 gene was studied in 27 mouse cell tumor lines. Transcripts of the gene have been found in 6 out of 7 different metastatic lines. No transcription of the gene has been observed in non-metastatic tumor lines. In normal tissues, specific gene DNA was only found in hemopoietic cells--in bone marrow, spleen, thymus and lymphocytes. Transcription of the gene mts271 is not dependent on the level of DNA methylation.

[Isolation of cDNA clones which are specifically transcribed in metastatic and nonmetastatic murine tumors]. / Vydelenie klonov kDNK, spetsificheski transkribiruemykh v metastaziruiushchikh i nemetastaziruiushchikh opukholiakh myshi.

Gene cloning was used with a view to examine differences in gene expression in metastatic (CSML-100) and non-metastatic (CSML-0) cell lines. Differential screening of the cDNA libraries obtained was performed. Mts271 gene which is specifically expressed in metastatic cells was isolated.

[Circular variants of long dispersed repeats in the mouse genome. The role of reverse transcriptase in their formation]. / Kol'tsevye formy dlinnykh dispergirovannykh povtorov v genome myshi. Rol' revertazy v ikh obrazovanii.

Extrachromosomal closed circular IAP gene DNA was cloned from Ehrlich ascites carcinoma cells. Two clones were analysed in detain and the following conclusions were drawn: 1) there is closed circular IAP gene DNA in mouse cells; 2) the formation of circular DNA and the transposition of IAP gene by means of reverse transcriptase are documented.