共查询到20条相似文献,搜索用时 15 毫秒
1.
A Lewiński 《Endokrinologie》1977,69(2):217-221
The effect of dopamine and TRH on the volume of prolactin cells nuclei in the rat anterior pituitary cultured in vitro has been investigated. A significant increase of volume of prolactin cells nuclei exposed to TRH has been shown. Dopamine had no significant influence on the volume of the nuclei of prolactin cells. The prolactin cells exposed to dopamine showed clearly an increased granulation. The obtained results suggest that dopamine exerts a stronger inhibiting effect on the release of prolactin than on its synthesis. 相似文献
2.
L A Strelkov R N Stepanenko A A Mikha?lova 《Biulleten' eksperimental'no? biologii i meditsiny》1987,104(12):703-706
Using double 3H-thymidine/14C-amino acid label, the influence of myelopeptides (MP) on chromosomal DNA and total protein (without histones) synthesis has been studied in vitro in mouse lymphoid organ cells. It has been shown that MP cause a decrease in DNA labelling and a parallel increase in protein labelling in bone marrow cells and have practically no effect on these two parameters in thymus, lymph node and spleen cells. It has been found that MP have only mitogenic effect on the above-mentioned organ cells, but in combination with 2-mercaptoethanol. The data obtained show that MP possess the properties of cell-differentiating factors. 相似文献
3.
N Ia Matsak N Ia Romanov A I Antokhin 《Biulleten' eksperimental'no? biologii i meditsiny》1987,103(1):89-92
Chalone-containing preparation has been obtained from ascitic Ehrlich's tumour by alcohol precipitation and the effect of various preparation doses on mitotic activity and DNA synthesis in the tumour has been studied. The preparation was shown to suppress tumour cell proliferation, acting on mitosis initiation and mitotic S phase as well as on DNA synthesis in the cells at S phase of mitotic cycle. The effect of the preparation on DNA synthesis in phase S cells was more pronounced than on cells entering DNA synthesis phase. The changes in all the parameters examined were dose-dependent. The preparation effect was tissue-specific. 相似文献
4.
Nelson G Wordsworth J Wang C Jurk D Lawless C Martin-Ruiz C von Zglinicki T 《Aging cell》2012,11(2):345-349
Senescent cells produce and secrete various bioactive molecules including interleukins, growth factors, matrix-degrading enzymes and reactive oxygen species (ROS). Thus, it has been proposed that senescent cells can damage their local environment, and a stimulatory effect on tumour cell growth and invasiveness has been documented. However, it was unknown what effect, if any, senescent cells have on their normal, proliferation-competent counterparts. We show here that senescent cells induce a DNA damage response, characteristic for senescence, in neighbouring cells via gap junction-mediated cell-cell contact and processes involving ROS. Continuous exposure to senescent cells induced cell senescence in intact bystander fibroblasts. Hepatocytes bearing senescence markers clustered together in mice livers. Thus, senescent cells can induce a bystander effect, spreading senescence towards their neighbours in vitro and, possibly, in vivo. 相似文献
5.
F V Donenko A O Kabieva N B Borovkova L V Moroz 《Biulleten' eksperimental'no? biologii i meditsiny》1991,112(10):423-424
Using P 388 and P 388/Dx tumour-bearing mice BDF1 it has been studied effect Tritton X-100 on accumulation and therapeutic action of doxorubicin (Dx). It has been shown that LD50 of Tritton X-100 is 153.6 mg/kg and MTD is 80 mg/kg body weight of animals. It has been shown that Tritton X-100 in dose 40 mg/kg body weight increases initial level of Dx in P 388/Dx cells to 215% and doesn't change accumulation of Dx in P 388 cells. It has been shown that Tritton X-100 doesn't influence the therapeutic effect of Dx in P 388 and P 388/Dx tumour-bearing mice. 相似文献
6.
E. V. Shamova O. D. Bichan E. S. Drozd I. V. Gorudko S. A. Chizhik K. B. Shumaev S. N. Cherenkevich A. F. Vanin 《Biophysics》2011,56(2):237-242
The effect of NO donors (sodium nitroprusside, S-nitrosoglutathione, dinitrosyl-iron complexes) on the functional and mechanical
properties of human platelets and red blood cells has been investigated. It has been established by atomic force microscopy
that NO donor-induced platelet disaggregation is accompanied by changes in the elastic properties of cells. It has been shown
that, in the presence of NO donors, the detergent-induced hemolysis of red blood cells is delayed, and the elasticity modulus
of these cells decreases. The results obtained indicate that NO donors regulate the structural and functional properties of
platelets and red blood cells. 相似文献
7.
The standardization of the in-vitro tetanus toxin neutralization test on Chinese hamster ovary cells
A A Khardina I P Amelina I A Lapaeva 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1991,(8):21-23
A test for the titration of B. pertussis toxin with antisera on Chinese hamster ovary (CHO) cells has been worked out. B. pertussis protective antigenic cell-free complex containing 48-54% of B. pertussis toxin has been used as antigen. The specificity of the effect of this complex on CHO cells has been confirmed in the toxicity neutralization test with antisera. CHO cells have been adapted to reagents and culture media made in the USSR. The titration of B. pertussis toxin and antisera on CHO cells did not require the use of highly purified antigen. 相似文献
8.
Background
5-AzaCytidine (AzaC) is a DNA demethylating drugs that has been shown to inhibit cell growth and to induce apoptosis in certain cancer cells. Induced expression of the galectin1 (Gal1) protein, a galactoside-binding protein distributed widely in immune cells, has been described in cultured hepatoma-derived cells treated with AzaC and this event may have a role in the effect of the drug. According to this hypothesis, we investigated the effect of AzaC and Gal1 on human lymphoid B cells phenotype. 相似文献9.
Inactivation of glyceraldehyde-3-phosphate dehydrogenase of human malignant cells by methylglyoxal 总被引:1,自引:0,他引:1
The effect of methylglyoxal on the activity of glyceraldehyde-3-phosphate dehydrogenase (GA3PD) of several normal human tissues and benign and malignant tumors has been tested. Methylglyoxal inactivated GA3PD of all the malignant cells (47 samples) and the degree of inactivation was in the range of 25-90%, but it had no inhibitory effect on this enzyme from several normal cells (24 samples) and benign tumors (13 samples). When the effect of methylglyoxal on other two dehydrogenases namely glucose 6-phosphate dehydrogenase (G6PD) and L-lactic dehydrogenase (LDH) of similar cells was tested as controls it has been observed that methylglyoxal has some inactivating effect on G6PD of all the normal, benign and malignant samples tested, whereas, LDH remained completely unaffected. These studies indicate that the inactivating effect of methylglyoxal on GA3PD specifically of the malignant cells may be a common feature of all the malignant cells, and this phenomenon can be used as a simple and rapid device for the detection of malignancy. 相似文献
10.
J. Nečas 《Biologia Plantarum》1974,16(2):94-101
The growth stimulating effect of 5-bromouracil and uracil on two strains of chlorococcal algae has been found in cell colonies grown from single cells, which were inoculated onto an agar medium. Analyses of the effect recorded in the cell cycles after treatment have revealed that the growth stimulating effect required four, or more, cell cycles to become evident. This has been proved by the number of autospores released from the treated cells and by the length of the lag phase after inoculation. The differences between the control and the treated population in some experiments with 5-bromouracil inChlorella and with uracil inScenedesmus obliquus have been visible by the unaided eye, whereas in some other experiments, they have been proved statistically. Growth stimulation has not been found only in a small number of experiments. The inhibition of growth induced by 5-bromouracil has been recorded in one experiment withScenedesmus quadricauda. 相似文献
11.
The effect of acidin-pepsin solution at a concentration of 1 : 100 on newly isolated Yersinia cultures has been tested in three series of experiments. Acidin-pepsin has been found to exert a bactericidal effect on Yersinia and to induce the appearance of involutionary forms and large rod-shaped Yersinia cells with a better capacity for survival. The surviving Yersinia cells do not pass their resistance to acidin-pepsin on to their progeny and show low invasiveness and pathogenicity in white mice. 相似文献
12.
T N Alakhov VYuMoskaleva EYu Kravtzova V V Smirnov I A Duvakin B V Loginov E S Severin 《Biotechnology and applied biochemistry》1988,10(6):563-567
The effects of Staphylococcus aureus enterotoxin A (SEA) on proliferative activities of human peripheral blood lymphocytes, B-lymphoma cells of the Namalva line, and nerve cells of the PC12 line have been studied. It has been shown that SEA affects these cells in identical ways, producing either a mitogenic or an antiproliferative effect. Studies on the dynamics of cellular responses to the action of SEA have demonstrated that the effects of the toxin are mediated by its interaction with different binding sites on the membranes of target cells. It has been established also that the antiproliferative effect of SEA is not associated with changes in 2',5'-oligo(A)-synthetase activity or in the level of interferon secretion. 相似文献
13.
M A Malatsidze G A Serobian Iu Iu Chirkov A S Sobolev 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1984,(9):33-37
The cyclic AMP (cAMP) system of mice fibroblasts L, clone B-82 has been studied. B-82 cells possess receptors to prostaglandin E1 (PGE1) and are deficient in beta-adrenoreceptors. It has been shown that 10 mM NaF, 1.10(-4) M GTP and 1.10(-5) M PGE1 stimulate adenylate cyclase of B-82 cells. PGE1 causes increase in the intracellular content of cAMP and protects B-82 cells against irradiation. Specifict beta-agonist isoproterenol fails to modulate adenylate cyclase activity and does not change cAMP content in B-82 cells. Isoproterenol has no effect on the B-82 cells radiosensitivity, although it is known to be a potent radioprotector. It is presumed that the stimulation of cAMP system by radioprotector is necessary for the performance of radioprotective effect. 相似文献
14.
Cells of the marine blue-green alga Gomphosphaeria aponina survive in mixed culture with the marine dinoflagellate, Gymnodinium breve (the Florida red tide organism), but G. breve cells lysed within 4-7 days. It has been established that the cytolytic effect of G. aponina, not nutrient competition, is responsible for the decrease in number of cells. The material elaborated by G. aponina has been termed aponin and has been extracted from the cells. The effect of aponin on the ichthyotoxicity of G. breve cultures was measured using Poecilia sphenops, adapted to sea water, as the assay organism. Aponin is not ichthyotoxic toward P. sphenops, though this material, when incubated with G. breve cultures does destroy the cells and increases the ichthyotoxicity of the cultures. At certain concentrations of aponin, the ichthyotoxicity of G. breve cultures appeared to be mitigate d. 相似文献
15.
Galimberti M Tolić-Nørrelykke IM Favillini R Mercatelli R Annunziato F Cosmi L Liotta F Santarlasci V Maggi E Pavone FS 《European biophysics journal : EBJ》2006,35(5):393-400
The effect of altered gravity on single cells has been reported in a number of studies. From the investigation of the immune system response to spaceflight conditions, interest has focused on the influence of gravity on single lymphocytes. Microgravity has been shown to decrease lymphocyte activation and to influence motility. On the other hand, the effect of hypergravity on lymphocyte motility has not been explored. We studied the migration of human peripheral blood T lymphocytes cultured in vitro in a hypergravity environment (10g). After hypergravity culture for 1–11 days, T cells were seeded on a fibronectin-coated glass surface, observed by time-lapse bright-field microscopy, and tracked by a computer program. We found that T cells, activated and then cultured in hypergravity, become motile earlier than cells cultured at normal gravity. These results suggest that hypergravity stimulates T cell migration. 相似文献
16.
I. A. Prudovsky R. B. Kosimov S. I. Sukharev T. V. Pospelova V. S. Prasolov A. V. Zelenin 《Cell proliferation》1993,26(3):221-233
Abstract. DNA synthesis regulation in heterokaryons between mouse neutrophils and cultured cells of various proliferative potentials has been studied. The following features have been found. Both immortalized and non-immortalized cells can reactivate DNA synthesis in neutrophil nuclei. The reactivation ability of cultured cells increases after immortalization and is not changed by further transformation. Neutrophils inhibit the entry of cultured cell nuclei into S phase and have no effect on ongoing DNA synthesis. Malignant cells are much less sensitive to the inhibitory action of neutrophils than non-malignant ones. Non-malignant immortalized cells are as sensitive to this effect as non-immortalized cells. Neutrophil karyoplasts do not influence DNA synthesis in partner cultured cell nuclei. Cycloheximide pretreatment of neutrophils drastically diminishes their inhibitory effect. 相似文献
17.
A study was made of the synthesis of nicotinamide adenine dinucleotide (NAD+) in the nuclei of kidney cells of dogs under normal conditions and upon the effect of the polyenic antibiotic amphotericin B. An active NAD-pyrophosphorylase has been found in the nuclei of kidney cells. It has been established that a intervenous introduction of amphotericin B stimulates NAD+ production. Amphotericin B also causes a decrease in the amount of histones in the nucleus. In the case of the nuclear membrane damage by a non-ionic detergent Triton X-100, no increase in the synthesis of NAD+ has been observed in the nuclei of kidney cells of animals treated with antibiotics, as opposed to the control ones. Under discussion is a question of a possible mechanism of the effect of polyenic antibiotics on the synthesis and metabolic activity of NAD+. 相似文献
18.
Role of nutritional zinc in the prevention of osteoporosis 总被引:1,自引:0,他引:1
Masayoshi Yamaguchi 《Molecular and cellular biochemistry》2010,338(1-2):241-254
19.
Thermic and pH modulation of phosphofructokinase (EC 2.7.1.11) activity with respect to fructose 6-phosphate has been studied comparatively in trout (Salmo gairdneri R.) haemopoietic cells and erythrocytes. Phosphofructokinase of both cellular populations displays a biphasic kinetic behaviour with respect to fructose 6-phosphate at two values of pH and temperature. In haemopoietic cells, when pH decreases the enzyme-substrate affinity increase while an opposite effect is found in erythrocytes. Decreases in temperature act as a positive modulator in haemopoietic cells while in erythrocytes this effect is observed only at low fructose 6-phosphate concentrations. Therefore a different pH and temperature modulation of phosphofructokinase during trout haemopoiesis has been established. 相似文献