[Quantitative changes in the cellular makeup of the spleen in mice infected with the Rauscher leukemia virus and Brucella abortus]. / Kolichestvennye izmeneniia kletochnogo sostava selezenki myshei, zarazhennykh virusom leikoza Raushera i Brucella abortus.

Changes in the absolute number of splenic cells of mice infected with Rauscher leukemia virus (RLV) and a day later--with living Brucella (BA) were studied. The increase in the absolute number of splenic cells of mice infected with RLV + BA was initially caused by the lymphoid tissue reaction to Brycella and then by the development of leukemia. The number of reticular cells in the spleen appeared to be larger than the control (RLV) within all observation periods; the number of basophilic normocytes amounted to the control, but an increase in the erythroblasts number was noted a week later and reached the control level by the 30th day, practically being unchanged subsequently. In mice receiving RLV + BA there was the increased monocyte, plasmatic cell, megakaryocyte, myeloid series cell count. The shift of splenic granulocytes to the "left", the development of leukocytosis, blood neutrophilia, in particular, lagged 1--2 weeks behind in such mice. The number of normocytes getting into the blood was decreased. All this would result in a significant extension of the lifespan in mice RLV + BA.

[Increase in the content of thymus hormone sensitive rosette-forming cell precursors in the spleen of mice vaccinated against smallpox]. / Uvelichenie soderzhaniia chuvstvitel'nykh k gormonu timusa predshestvennikov rozetkoobrazuiushchikh kletok v selezenke vaktsinirovannykh ospennoi vaktsinoi myshei.

Smallpox vaccine injection to 2-month-old C57BL/6j female mice caused during the first days significant rise in the number of precursor cells of rosette-forming lymphocytes, sensitive to the differentiating thymus extract effect. The number of these cells returned to the normal level by the 10th day after vaccination.

[Hematopoietic tissue reactions associated with the growth of syngeneic transplanted tumors in mice]. / Reaktsii krovetvornoi tkani, assotsiirovannye s rostom singennykh perevivaemykh opukholei u myshei.

Hemangiopericytoma growth in syngeneic male mice F1 (CBA X C57BL/bj) led to regular hemopoietic changes: an increase in the spleen weight, spleen cell count, in the number of colony-forming units (CFU). It also induced augmentation of myelopoiesis in the spleen and leukocytosis with a sharp increase of segmented granulocytes in the circulating blood characterized as the "leukemoid reaction" syndrome. The latter occurred even when the tumour cells were transplanted into the splenectomized host. Although less marked, this leukemoid reaction was also noted in advanced hepatoma transplanted to syngeneic male mice F1 (CBA X C57BL/6j). No leukemoid reaction was observed in these mice after grafting syngeneic strain of urinary bladder carcinoma.

[Selective treatment of leukemia L1210 with combination of deoxycytidine and lethal doses of cytosine arabinoside]. / Selektivnaia terapiia leikemii L1210 kombinatsiei dezoksitsitidina i letal'nykh doz tsitozin-arabinozida.

Oral administration of deoxycytidine simultaneously with intraperitoneal injections of toxic doses of cytosine arabinosidetomice with advanced L1210 leukemia diminished the toxic effects preventing drug death of these mice. They developed a marked antitumor effect. The mean survival time of these mice was considerably extended as compared to that of untreated animals or those given one of these drugs alone. At the optimum schedule of treatment about 23% of the mice survived over 60 days. Deoxycytidine protection reduced the antileukemic effect of cytosine arabinoside administered in nontoxic doses. The deoxycytidine plus cytosine arabinose combination was ineffective in the treatment of transplantable myeloid leukemia in mice.

[Kinetics of hematopoietic stem cells in the bone marrow of hepatectomized mice]. / Kinetika stvolovykh krovetvornykh kletok v kostnom mozge gepatéktomirovannykh myshei.

Two-thirds of the liver was removed from (CBA X C57BL/6j) F1 female mice. A significant increase of the number of endogenous colonies count in the spleen of partially hepatectomized mice was observed on the 5-th day after the operation. This increase was not associated with the changes in the number of stem cells in the bone marrow as partial hepatectomy at different times after the operation exerted no effect on the number of colony-forming units (CF1) in the bone marrow.

[Protection of the mouse digestive tract from the toxic effect of cytosine-arabinoside]. / Zashchita pishchevaritel'nogo trakta myshei ot toksicheskogo vliianiia tsitozin-arabinozida.

Comparative experiments have demonstrated a qualitative difference of protective effects, observed in peroral application of 2'-desoxycytidine molecular solution and activated carbon suspension with 2'-desoxycytidine molecules adsorbed onto its particles with regard to the toxicity of intraperitoneal injections of cytosine arabinoside in female C57bl/6j mice. In contrast to 2'-deosyxycytidine molecular solution, which reduced all toxic manifestations and protected animals from death, the corpuscular form of the protector only the toxic effect of the antimetabolite on the intestine without affecting other toxic manifestations, the inhibition of hemopoiesis in particular.

[Tumor angiogenesis factor and its possible utilization]. / Opukholevyi angiogennyi faktor i vozmozhnosti ego ispol'zovaniia.

A brief survey of the literature data on tumor angiogenic factor stimulating intratumor growth of new vessels is given. Under consideration is the possibility to use inhibitors of the factor, in particular antibodies against it, to suppress tumor growth. Also, it is suggested to use tumor angiogenic factor for revascularization of infarction and ischemic tissues, especially in myocardial ischemia.

[Approach to the development of an actovaccine using vaccinia virus as a model]. / O podkhode k pazrabotke aktovaktsiny na modeli virusa ospovaktsiny

Injection of living vaccinia virus to the mesenteric vein of rabbits leads to its accumulation in liver in high concentration. In the other series of experiments vaccinia virus inactivated with gamma-radiation was inoculated into the mesenteric vein. Later on the animals were sacrificed at various dates. Homogenates were prepared from their liver. Comparative study of these homogenates made it possible to reveal increased immunogenic activity of homogenate obtained 24 hours after intravenous inoculation of inactivated vaccinia virus into animals. Immunogenic activity of this homogenate was more clearly manifested than immunogenic activity of the antigen itself--inactivated vaccinia vorus. Neither original inactivated vaccinia virus nor inactivated virus absorbed by Kupffer cells induced antibody formation. It is supposed that vaccines may be prepared from various viruses or tumor cells treated with macrophages with subsequent chemical extraction of the most immunogenic fraction.

[Effect of Trichinella spiralis infection on the development of Rauscher leukemia]. / Vliianie invazii Trichinella spiralis na razvitie leikoza Raushera

The influence of Trichinella spiralis on the course of Rausher leukemia in mice was studied. Inoculation of mice with Trichinella spiralis larvae 15, 16 and 30 days before infection with Rausher leukemia virus was shown to stimulate splenomegaly, whereas preinoculation of Rausher leukemia virus at 6, 12 and 18 days before infection with Trichinella spiralis resulted in inhibition of splenomegaly. Under the experimental conditions used, no effect of T. spiralis on reproduction of Rausher leukemia virus was observed, as virus titers in the plasm of mice with marked stimulation or inhibition of splenomegaly were identical and did not differ from those in mice without Trichinella spiralis invasion.

[Transplantable cancer of the urinary bladder and hemangiopericytoma obtained by means of the ectopic transplantation of tissues of the fetal urinary bladder]. / Perevivaemyi rak mochevogo puzyria i gemangioperitsitoma poluchennye putem éktopicheskoi transplantatsii tkani mochevogo puzyria ploda

Organ-like cysts appear to develop after subcutaneous transplantation of minced tissues of fetal urinary bladder into adult syngeneic recipients. These are multilocular cysts lined with epithelium and filled with secretion. Many months later they undergo a spontaneous malignant tranformation. Transplantable strains of vesical cancer and hemangiopericytoma have been obtained.