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E. B. Burova I. S. Smirnova A. N. Shatrova I. V. Gonchar N. N. Nikolskii 《Cell and Tissue Biology》2011,5(1):9-14
Interferon gamma (IFNγ) is known to inhibit the proliferation of some transformed cell lines. Recently, we demonstrated the
transactivation of the epidermal growth factor receptor (EGFR) in response to IFNγ (Burova et al., 2007) and provided direct
evidence for the dependence of IFNγ-induced EGFR transactivation on the EGFR expression level in epithelial cells (Gonchar
et al., 2008). This study examines an antiproliferative effect of IFNγ on human epithelial cell lines—A431 and HeLa that express
high levels of EGFR, as well as HEK293 that expresses low levels of EGFR. To characterize the IFNγ-induced changes in these
cells, we studied cell growth, the cell cycle, and induction of apoptosis. The response to IFNγ differed in the compared cell
lines; cell growth was inhibited in both A431 and HeLa cells, but not in HEK293 cells, as was shown by the cell count and
MTT. The cell-cycle phases analyzed by flow cytometry were disturbed in A431 and HeLa cells in response to IFNγ. On the contrary,
in HEK293 cells, the IFNγ treatment did not alter distribution by cell cycle phases. Our results indicate that IFNγ produces
an antiproliferative effect that depends on the increased expression of EGFR in A431 and HeLa cells. Furthermore, it was demonstrated
that IFNγ induced the caspase 3 activation in A431 cells, which suggests the involvement of active caspase 3 in the IFNγ-induced
apoptosis. 相似文献
3.
L F Adigamov L I Smirnova V D Nifontov M P Chernikov 《Biulleten' eksperimental'no? biologii i meditsiny》1985,99(6):687-689
The levels of thyroid, pituitary and steroid hormones-thyroxine, triiodothyronine and 11-hydroxycorticosteroids in the blood serum, somatotropin in the pituitary, and processes of protein assimilation were studied in rats in the early postnatal period. The highest endogenous production of thyroxine, triiodothyronine and somatotropin was detected in 15-day-old rats. The highest level of protein utilization was detected in 7 to 15-day-old rats, followed by the lowering of the utilization on changing over to definitive nutrition. Endogenous production of the anabolic hormones thyroxine, triiodothyronine and somatotropin was found to correlate with a high level of protein utilization in rats within the first days of life after birth. 相似文献
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Ekaterina Maidji Galina Kosikova Pheroze Joshi Cheryl A. Stoddart 《Journal of virology》2012,86(23):12795-12805
Human cytomegalovirus (HCMV) is the leading viral cause of birth defects and life-threatening lung-associated diseases in premature infants and immunocompromised children. Although the fetal lung is a major target organ of the virus, HCMV lung pathogenesis has remained unexplored, possibly as a result of extreme host range restriction. To overcome this hurdle, we generated a SCID-hu lung mouse model that closely recapitulates the discrete stages of human lung development in utero. Human fetal lung tissue was implanted into severe combined immunodeficient (CB17-scid) mice and inoculated by direct injection with the VR1814 clinical isolate of HCMV. Virus replication in the fetal lung was assessed by the quantification of infectious virus titers and HCMV genome copies and the detection of HCMV proteins by immunohistochemistry and Western blotting. We show that HCMV efficiently replicated in the lung implants during a 2-week period, forming large viral lesions. The virus productively infected alveolar epithelial and mesenchymal cells, imitating congenital infection of the fetal lung. HCMV replication triggered apoptosis near and within the viral lesions and impaired the production of surfactant proteins in the alveolar epithelium. Our findings highlight that congenital and neonatal HCMV infection can adversely impact lung development, leading to pneumonia and acute lung injury. We have successfully developed a small-animal model that closely recapitulates fetal and neonatal lung development and provides a valuable, biologically relevant tool for an understanding of the lung pathogenesis of HCMV as well as other human respiratory viruses. Additionally, this model would greatly facilitate the development and testing of new antiviral therapies for HCMV along with select human pulmonary pathogens. 相似文献
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A I Lysenko E D Smirnova S I Somina 《Biulleten' eksperimental'no? biologii i meditsiny》1984,97(3):274-277
Ischemia of the rat small intestine lasting 40 min leads to pronounced structural disorders in lipid transport across the enterocytes, reduction in enzymatic activity of the cells and in absorption function, and to the loss of fat with feces. The normalization of the indicated parameters occurs at varying times and ends after 1 month. Fat transport abnormality is marked by an increase in lipid drops in the cavities of the smooth endoplasmic network, appearance of large and numerous matrix lipids, by a greater reduction, as compared to normal, in the membranes of the rough endoplasmic network and lamellar complex in the epithelium of the villi. Accumulation of lipids and retardation of their release from the cytoplasm are determined by incomplete differentiation of the epithelium, which is also combined with a decreased enzymatic activity. 相似文献
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A mathematical model of autoimmunity is developed. This model is a system of two nonlinear differential equations, which describe the concentration dynamics of tissue cells and agressive lymphocytes. An analysis of the solutions shows that this model reproduces general behaviour of autoimmune diseases. 相似文献
10.
The dependence of adrenal gland adenylate cyclase desensitization on the dose of in vivo injected ACTH, the time of occurrence and duration of the enzyme refractory period and the dependence of desensitization on the number of ACTH injections were analyzed. The experiments were carried out on guinea pigs injected with prolonged action preparations of ACTH (4 and 6 units) daily for 1-6 days. Intramuscular injections of ACTH caused adenylate cyclase refraction to the repeated action of the hormone. The effect of desensitization was the most conspicuous within the first few hours after hormone injection. The decrease of adenylate cyclase sensitivity and the duration of this effect were found to depend on the ACTH dose as well as on the number of injections. It has been shown for the first time that a single in vivo injection of 0.9% NaCl causes short-term desensitization of adenylate cyclase to the repeated action of much higher doses of ACTH in vitro, presumably due to endogenous ACTH release in response to weak stress exposure. The periodicity of changes in adenylate cyclase sensitivity upon prolonged hormone administration is discussed. Sensitization of the enzyme upon daily short-term exposure to physiological doses of ACTH (administration of 0.9% NaCl for 6 days) was revealed. 相似文献