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1.
Marie Lipoldová Helena Havelková Jana Badalová Jarmila Vojtíšková Lei Quan Magdaléna Krulová Yahya Sohrabi Alphons P. Stassen Peter Demant 《Cancer immunology, immunotherapy : CII》2010,59(2):203-213
Low infiltration of lymphocytes into cancers is associated with poor prognosis, but the reasons why some patients exhibit
a low and others a high infiltration of tumors are unknown. Previously we mapped four loci (Lynf1–Lynf4) controlling lymphocyte infiltration of mouse lung tumors. These loci do not encode any of the molecules that are involved
in traffic of lymphocytes. Here we report a genetic relationship between these loci and the control of production of IFNγ
in allogeneic mixed lymphocyte cultures (MLC). We found that IFNγ production by lymphocytes of O20/A mice is lower than by
lymphocytes of OcB-9/Dem mice (both H2
pz
) stimulated in MLC by irradiated splenocytes of C57BL/10SnPh (H2
b
) or BALB/cHeA (H2
d
) mice, or by ConA. IFNγ production in MLCs of individual (O20 × OcB-9)F2 mice stimulated by irradiated C57BL/10 splenocytes and genotyped for microsatellite markers revealed four IFNγ-controlling
loci (Cypr4-Cypr7), each of which is closely linked with one of the four Lynf loci and with a cluster of susceptibility genes for different tumors. This suggests that inherited differences in certain
lymphocyte responses may modify their propensity to infiltrate tumors and their capacity to affect tumor growth. 相似文献
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J. Čatský D. K. Velichkov Jana Pospísilová Jarmila Solárová Ingrid Tichá 《Biologia Plantarum》1987,29(5):355-364
The carbon balances of whole, 21-d old French bean plants (Phaseolus vulgaris L.) grown in standard nutrient solution (1K) and its modifications without (OK) or surplus (2K) potassium were calculated
from the daily photosynthetic carbon inputs of individual leaves, and the daily respiratory carbon losses by individual leaves,
stalks and petioles, and roots. Under the three K concentrations, maximum net photosynthetic rates (Pn) were found in the 2nd or in the 3rd trifoliate leaves, maximum respiratory rates (Rd) in the youngest, 4th trifoliate leaves; the Pn/Rd ratio decreased with leaf age. In all leaves of 2K plants, leaf dry masses and thicknesses, Pn, Pn/Pd ratios, and stomatal and intracellular conductances were lower than in OK and IK plants. Daily whole-plant net carbon gain
was highest in IK plants, whereas in OK and 2K plants it was 98.0 and 81.3 % of IK, respectively. Similar values were found
in the parameters of growth analysis, namely in net assimilation rates and relative growth rates.
No differences were found in water potential (Ψ
w
) or water saturation deficit (Wsat) in the OK, 1K and 2K plants sufficiently supplied with water or during wilting and resaturation. The decrease in Ψw to −0.97 MPa was associated with a 19.9 %, 31.4 % and 23.4 % decrease in Pn of OK, 1K and 2K plants, respectively, but no effect on Rd was found. In the three variants, the short-time effect of mild water stress was fully reversible. 相似文献
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Jana Pospíšilová 《Biologia Plantarum》1988,30(5):393-396
UsingNicotiana tabacum L. plantlets cultivatedin vitro as a model system it was proved that osmotic adjustment may be caused by a decrease in water potential of substrate as well
as by a decrease in air humidity. 相似文献
9.
Amit Kumar Jana Sanjiv Agarwal S. N. Chatterjee 《Radiation and environmental biophysics》1986,25(4):309-314
Summary Ultrasonic radiation produced a dose dependent linear increase in lipid peroxidation (MDA formation) in the liposomal membrane. The yield of MDA was significantly inhibited by butylated hydroxytoluene (BHT), the antioxidant, sodium formate, the OH radical scavenger, and EDTA, the metal ion chelator. Ascorbic acid at low concentration increased the ultrasonic induced MDA formation while high concentrations inhibited lipid peroxidation. A mechanism of ultrasound induced lipid peroxidation is suggested. 相似文献
10.
A correlation between intracellular phospholipid levels and the rate of exoprotein synthesis was investigated in the filamentous fungus Trichoderma reesei QM 9414 during growth on cellulose. When the incubation temperature was varied between 20 and 37°C, the exoprotein synthesis rate correlated with the total cellular amount of phospholipids, but not with an individual phospholipid component. In contrast, when phospholipid bases were added exogenuously, a significant stimulation of exoprotein synthesis was observed with choline. The addition of the surfactant Tween 80—which also stimulates exoprotein secretion in T. reesei QM 9414—prevented choline stimulation. Optimal stimulation occurred around 20 mM choline. Choline stimulated exoprotein synthesis in general as shown by increased activities of several extracellular enzymes. Mycelia required preincubation for at least 20 h before stimulation of choline could be seen. Mycelia pregrown in the absence or presence of choline were equally effective in formation of -glucosidase upon induction with methyl--d-glucoside, and the addition of choline to the induction medium had no effect. Choline did not alter the osmotic stability of protoplasts of T. reesei. Electron microscopic examinations and analysis of chemical constituents as well as marker enzymes from choline grown and non-choline grown mycelia revealed higher contents of mitochondria and endoplasmic reticula in choline grown mycelia. The possibility is discussed that choline may stimulate exoprotein synthesis by increasing the cellular content of endoplasmic reticula. 相似文献