A glycoprotein: galactosyltransferase activity in the ascitic fluid and serum of mice with the YC8 tumor]

Tranfer of (14C)-gal from exogenous UDP(14C)-gal has been demonstrated with ovomucoid as glycoprotein acceptor in ascitic fluid sera from Balb/c mice bearing isogenic YC8 tumor. Transfer exists without ovomucoid, in great ratio in ascitic fluid and in sera from ascitic mice too, showing occurrence of endogenous acceptors, the origin of which has to be proved.     

Demonstration of N-acetylgalactosaminyltransferase activity in the murine lymphoma YC8]

The N-acetyl-galactosaminyltransferase activity has been studied in the biological fluids of YC8-lymphoma bearing Balb/c mice. It is enhanced during tumor development from 1 to 30 times in peritoneal fluids and from 1 to 10 times in sera. This activity is nil in urines. Optimal requirements for activity have been determined. Results suggest the existence, during tumor process not only of an enhancement of enzymatic activity, but also of a new molecule synthesis, molecules which are endogenous acceptors for the enzyme.     

Mast cells in the pinna of Balb/c 'nude' (nu/nu) and heterozygotes (ny/+)mice.

The relative number of mast cells in the ear lobes' skin (pinna) of nude (athymic) nu/nu and normal (thymic) nu/+ heterozygotes of Balb/c mice was similar. The results obtained contradict some suggestions about the general influence of the thymus on the number of mast cells in the skin and suggest the existence of some local factor(s) in regulation of skin mast cell numbers.     

Mast cells in the pinna of Balb/c ‘nude’ (nu/nu) and heterozygotes (nu/+) mice

Summary The relative number of mast cells in the ear lobes' skin (pinna) of nude (athymic) nu/nu and normal (thymic) nu/+ heterozygotes of Balb/c mice was similar. The results obtained contradict some suggestions about the general influence of the thymus on the number of mast cells in the skin and suggest the existence of some local factor(s) in regulation of skin mast cell numbers.This work was supported by grant No. CA16426.The author wishes to thank Dr Kenneth Morrison for supplying the mice and the discussion, Mr Duffy Michowski for taking care of the animals used, Mr Carl Polley for taking the pictures and Dr N. R. Rose for the discussion.     

Demonstration of nucleotide pyrophosphatase and phosphohydrolase activities in normal lymphocyte of Balb/c mice and absence of these activities in YC8 tumor cells and in lymphocytes of animals with YC8 lymphoma]

Saline extraction of tumor cells from YC8 lymphoma transplanted in Balb/c Mice, of lymphocytes from animals bearing this tumor and of lymphocytes from control animals, allowed us to show important hydrolytic activities towards UDP-[(14C)]-galactose and galactose-[(14C)]-1-phosphate in normal lymphocytes. These activities disappear in lymphocytes from Mice bearing this tumor and in tumor cells themselves.     

Radioprotection conferred by Corynebacterium parvum against the lethality caused by X irradiation at sublethal and lethal doses in the mouse]

Intraperitoneal injection of Corynebacterium parvum (C. parvum) into Balb/c mice produces a protection against toxicity or lethality provoked by ionizing radiation (750 R and 950 R). Survivals reaching nearly 90 days have been recorded.     

金丝桃素抑制慢性病毒性心肌炎小鼠心肌细胞凋亡及Fas／FasL蛋白表达

目的观察金丝桃素对慢性病毒性心肌炎（VMC）小鼠心肌细胞凋亡及Fas／FasL蛋白表达的影响。方法Balb／C小鼠多次接种心肌柯萨奇段病毒复制慢性VMC模型,首次感染病毒45天后将存活小鼠分为模型组、金丝桃素组及氯沙坦组,同时设正常对照组．分别给予相应药物干预30天,采用原位末端标记法检测心肌细胞凋亡及免疫组化方法检测Fas／FasL蛋白表达。结果模型组心肌细胞凋亡率较正常组显著增加（P〈0．05）,金丝桃素组和氯沙坦组凋亡率较模型组显著降低（P〈0．05）。模型组Fas／FasL蛋白表达较正常组显著增多（P〈0．01）,金丝桃素组和氯沙坦组较模型组显著降低（P〈0．01）。结论金丝桃素保护心肌细胞与抑制VMC心肌细胞的凋亡．下调Fas／FasL蛋白表达有关。     

Effects of 9.4 GHz microwave exposure on meiosis in mice.

Exposure to 9.4 GHz pulsed microwaves at low power densities for 1 h/day during 2 weeks induces in adult male Balb/c mice disturbances in meiosis, consisting in an increase of translocations and the appearance of cells with several chromosome pair remaining univalents at MI.     

Scanning electron microscopy of antibody-dependent cell-mediated cytotoxicity of Friend leukemia virus-infected spleen cells.

Friend leukemia virus (FLV) infected splenocytes treated with rabbit anti-FLV serum and subsequently incubated with splenic lymphocytes from non-immune Balb/c mice were examined by scanning electron microscopy. Villous-covered lymphocytes adherred to the tumor cells and induced surface blebs, numerous membrane pores and eventual tumor cell lysis.     

Scanning electron microscopy of antibody-dependent cell-mediated cytotoxicity of Friend leukemia virus-infected spleen cells

Summary Friend leukemia virus (FLV) infected splenocytes treated with rabbit anti-FLV serum and subsequently incubated with splenic lymphocytes from non-immune Balb/c mice were examined by scanning electron microscopy. Villous-covered lymphocytes adherred to the tumor cells and induced surface blebs, numerous membrane pores and eventual tumor cell lysis.     

Suppression of humoral immune response in mice by administration of high molecular levan

Summary High molecular levan, a polyfructoside, has a dose-dependent inhibitory effect on the primary immune response to sheep red cells (SE) in Balb/c mice, when given as from 1–2 days prior to the antigen injection. A slight stimulation of the immune response was observed when levan was given shortly before or 1 day after the antigen.     

Evidence of urinary glomerular basement membrane (GBM) antigens excretion in 3 rodents (rat, mouse, and guinea-pig) (author's transl)]

Immunodiffusion technique, with rabbits antibodies against rat glomerular basement membrane (GBM), permits to evidence the presence of GBM antigens into normal urines of 3 rodents (rat, mouse, and guinea-pig). These results confirm the earlier works in human and rabbit urines and show the antigenic communauty existing between the 3 rodents GBM, since we can evidence antigens of 3 different mammals with the same antibody. The origin and the nature of this patterns and the signification of this presence into mammalian urines are discussed.     

Aryl-hydrocarbon receptor-dependent alteration of FAK/RhoA in the inhibition of HUVEC motility by 3-methylcholanthrene

We previously demonstrated the antiproliferative and antiangiogenic effects of 3-methylcholanthrene (3MC), an aryl-hydrocarbon receptor (AhR) agonist, in human umbilical vascular endothelial cells (HUVECs). Herein, we unraveled its molecular mechanisms in inhibiting HUVEC motility. 3MC down-regulated FAK, but up-regulated RhoA, which was rescued by AhR knockdown. It led us to identify novel AhR binding sites in the FAK/RhoA promoters. Additionally, 3MC increased RhoA activity via suppression of a negative feedback pathway of FAK/p190RhoGAP. With an increase in membrane-bound RhoA, subsequent stress fiber and focal adhesion complex formation was observed in 3MC-treated cells, and this was reversed by a RhoA inhibitor and AhR antagonists. Notably, these compounds significantly reversed 3MC-mediated anti-migration in a transwell assay. The in vitro findings were further confirmed using an animal model of Matrigel formation in Balb/c mice. Collectively, AhR’s genomic regulation of FAK/RhoA, together with RhoA activation, is ascribable to the anti-migration effect of 3MC in HUVECs.     

Compared expression of murine plasmacytoma associated virus in tumor cells and in mouse embryo cells]

A DNA complementary to the viral genome of C-type particles produced by a Mouse myeloma derived cell line (MF2 cell line) was synthesized. This cDNA was used as a probe to study the viral genome expression among the total RNA and the poly (A)-rich RNA extracted from the MF2 and Balb/c embryonic cells. As evidenced by molecular hybridization experiments, the presence of at least one endogenous Balb/c virus in the MF2 virus stocks is suggested. In the productive cells, the viral RNA sequences are expressed in the poly (A)-rich RNA fraction.     

Prediction of glycan structures of human N-glycoproteins]

By adding the sequence beta-(1 leads to 4)-GlcNAc-beta-(1 leads to)-Asn or alpha Fuc-(1 leads to 6 or 3)-beta-(1 leads to 4)-GlcNAc-beta-(1 leads to)-Asn to the oligosaccharides isolated from human urines of mannosidosis, fucosidosis and sialidosis, we are able to reconstitute numerous structures of asparaginyl-glycans. We postulate i) that these structures which have not yet been characterized pre-exist in glycans of human glycoproteins, probably in the cytoplasm or/and the cell membrane; ii) that they are products of the action of endo-beta-N-acetyl-glucosaminidases which are protected because of the lack of exoglycosidases and accumulate in the cells, and then in the urine.     

Chemotactic and random movement of cord-blood granulocytes

Summary Chemotactic responsiveness and random movement of cord-blood granulocytes were studied with a modified Boyden's method. Cord-blood granulocytes were less active chemotactically than granulocytes from healthy children and adults, whereas the random filter movement of the cells from all three sources was about the same. In cord sera, concentrations of cell directed chemotaxis inhibitors were equal to those in sera from other age groups. Compared with the situation in healthy children and adults, the generation of chemotactic factors in cord-blood sera was impaired. This impairment was not related to an increased activity of chemotactic factor inactivators. Measurement of the cyclic nucleotide levels in granulocytes from cord-blood and from children belonging to various age groups revealed that the cord granulocytes have significantly lower concentrations of cAMP and cGMP, which could have been responsible for the decreased chemotactic responsiveness.     

Chemotactic and random movement of cord-blood granulocytes

Chemotactic responsiveness and random movement of cord-blood granulocytes were studied with a modified Boyden's method. Cord-blood granulocytes were less active chemotactically than granulocytes from healthy children and adults, whereas the random filter movement of the cells from all three sources was about the same. In cord sera, concentrations of cell directed chemotaxis inhibitors were equal to those in sera from other age groups. Compared with the situation in healthy children and adults, the generation of chemotactic factors in cord-blood sera was impaired. This impairment was not related to an increased activity of chemotactic factor inactivators. Measurement of the cyclic nucleotide levels in granulocytes from cord-blood and from children belonging to various age groups revealed that the cord granulocytes have significantly lower concentrations of cAMP and cGMP, which could have been responsible for the decreased chemotactic responsiveness.     

Effects of 9.4 GHz microwave exposure on meiosis in mice

Summary Exposure to 9.4 GHz pulsed microwaves at low power densities for 1 h/day during 2 weeks induces in adult male Balb/c mice disturbances in meiosis, consisting in an increase of translocations and the appearance of cells with several chromosome pair remaining univalents at MI.Acknowledgments. Grant No. 30121/120/53674 of the Centre International des Etudiants et Stagiaires to E. Manikowska and grant No. 78-1017/DRED of the Direction des Recherches et Etudes Techniques du Ministère de Défense to B. Servantie accorded by the French Government are gratefully acknowledged. The authors express their thanks to Miss M.R. Morazzani for her technical assistance.     

Change in levels of cholesterol and free fatty acids of lymphoid cells during tumor growth

Summary Growth of Ehrlich's ascitic carcinoma in mice resulted in increase of free cholesterol and free fatty acids in lymphoid cells from thymus, spleen and cervical lymph node, but decrease of these lipids in the cells from mesenteric lymph node.     

Change in levels of cholesterol and free fatty acids of lymphoid cells during tumor growth.

Growth of Ehrlich's ascitic carcinoma in mice resulted in increase of free cholesterol and free fatty acids in lymphoid cells from thymus, spleen and cervical lymph node, but decrease of these lipids in the cells from mesenteric lymph node.