Thymus tumors

ACTH-secreting non-pituitary tumors (ectopic ACTH syndrome)—15% of cases of endogenous Cushing s syndrome usually from small cell lung carcinoma, bronchial carcinoids, pheochromocytoma, or thymus, pancreatic, ovarian, or thyroid tumor. The tumor is usually disseminated (difficult to localize). 

Thymoma A tumor derived from the epithelial or lymphoid elements of the thymus. 

Mouse 0.2 mg/kg BW Reduces mammary tumor growth rate adversely affects thymus gland growth 22... 

In different organs of the rat [128], Ehrlich ascites tumor cells [144], trout testis [127], calf thymus [145], and carp testis [146], H4 is modified mainly as the N -dimethyllysine, while H3 is modified as N -monomethyllysine, N -dimethylly-sine and N -trimethyllysine with the N -dimethyllysine predominating. Pea seedling H4 is not methylated and H3 exits as N -mono- and N -dimethyllysine with N -trimethyllysine not being detectable [147,148]. 

Corticosteroids suppress both humoral and cellular immunity. Single doses produce a redistribution of lymphocytes with a concentration dependent decrease of CD4 and CDS positive cells. This in vivo lymphopenic effect correlates with the in vitro inhibition of stimulated T-cell proliferation. Furthermore, corticosteroids are able to inhibit the expression of genes coding for IL-1, IL-2, IL-6, interferon a, and tumor necrosis factor, TNE-a. Chronic administration decreases the size and also the cellu-larity of lymphoid tissues like lymph nodes, spleen, and thymus. Corticosteroids have more effect on the primary immune response and are less effective against previously sensitized immune responses. Their suppressive effects are more pronounced for T-cell immune responses than for the humoral immune response. 

Genotoxic Effects. Genotoxic Effects. HDI was demonstrated to be non-mutagenic against some Salmonella typhimurium strains with or without metabolic activation (Anderson et al. 1980). HDI also inhibited the growth of Ehrlich ascites tumor eells in female mice (Moos et al. 1971) and decreased the mutation frequency in Escherichia coli (Kawazoe et al. 1981). Calf thymus DNA incubated in vitro with 10.4 or 52 mol of HDI for 10 or 20 minutes produeed no evidence of intrastrand cross-links or DNA strand breaks (Peel et al. 1997). No studies were located that studied the genotoxic effects of HDI on human cells or that deseribed the ability of prepolymer forms of HDI to induce genotoxicity."... 

Shore, R.E., Woodard, E., Hildreth, N., Dvoretsky, R, hemplemann, L. and Pasternack, P. (1985). Thyroid tumors following thymus irradiation, J. Natl. Cancer Inst. 74,1177. 

In the spleen, the absolute numbers of CD4 or CD8 single positive T cells and CD4CD8 double positive T cells increased in the tumor-bearing state, Fig. (11). The increment in CD8 single positive T cells was augmented significantly by CVS administration. In the thymus, the absolute number of the double positive T cells slightly increased in the CVS-injected mice. 

Most of these compounds displayed very potent cytotoxic activity against several tumor cells. Dercitin (435) was also active in vivo, prolonging the life of P388-bearing mice with a T/C of 170 at 5 mg/Kg. Compound 435 inhibited both DNA and RNA synthesis, DNA polymerase and I/DNase nick translation, bound to calf thymus DNA, and relaxed supercoiled <()X174DNA [348]. The compounds also showed... 

Lymphocytic Tumors of Thymic Origin. The appearance of spontaneous tumors (e. . SAKRTLS-13) in AKR and C58 mice (27) is quite common. Other thymic tumors can also be induced chemically (28) (BALENTL—3, -5 or P-1798 Table I) or virally (Moloney leukemia virus (29)). in the early stage of tumor development they are confined to the thymus, but later the tumor is metastasized to the spleen, liver, kidney, and lymph nodes. 

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