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Rafał Krętowski Anna Stypułkowska Marzanna Cechowska-Pasko 《Molecular and cellular biochemistry》2015,398(1-2):165-173
The inhibition of the 26S proteasome evokes endoplasmic reticulum stress, which has been shown to be implicated in the antitumoral effects of proteasome inhibitors. The cellular and molecular effects of the proteasome inhibitor—bortezomib—on human colon cancer cells are as yet poorly characterized. Bortezomib selectively induces apoptosis in some cancer cells. However, the nature of its selectivity remains unknown. Previously, we demonstrated that, in contrast to normal fibroblasts, bortezomib treatment evoked strong effect on apoptosis of breast cancer cells incubated in hypoxic and normoxic conditions. The study presented here provides novel information on the cellular effects of bortezomib in DLD-1 colon cancer cells line. We observe twofold higher percentage of apoptotic cells incubated for 48 h with 25 and 50 nmol/l of bortezomib in hypoxic conditions and four-, fivefold increase in normoxic conditions in comparison to control cells, incubated without bortezomib. It is of interest that bortezomib evokes strong effect on necrosis of DLD-1 colon cancer cell line. We observe the sixfold increase in necrosis of DLD-1 cells incubated with 25 or 50 nmol/l of bortezomib for 48 h in hypoxia and fourfold increase in normoxic conditions in comparison to adequate controls. We suggest that bortezomib may be candidates for further evaluation as chemotherapeutic agents for human colon cancer. 相似文献
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Jacek Kęsy Beata Maciejewska Magdalena Sowa Magdalena Szumilak Krzysztof Kawałowski Maja Borzuchowska Jan Kopcewicz 《Plant Growth Regulation》2008,55(1):43-50
It has been shown that both IAA and ethylene application inhibit flower induction in the short-day plant Pharbitis nil. However application of IAA has elevated ethylene production in this plant, as well. Strong enhancement of ethylene production
is also correlated with the night-break effect, which completely inhibits flowering. In order to determine what the role of
IAA and ethylene is in the photoperiodic flower induction in Pharbitis nil, we measured changes in their levels during inductive and non-inductive photoperiods, and the effects of ethylene biosynthesis
and action inhibitors on inhibition of flowering by IAA. Our results have shown that the inhibitory effect of IAA on Pharbitis nil flowering is not physiological but is connected with its effect on ethylene biosynthesis. 相似文献
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T. Cichocki B. Gonsior J. Glazur M. Höfert L. Jarczyk E. Rokita A. Strzałkowski M. Sych 《Biological trace element research》1987,13(1):167-177
The elemental composition of rabbit liver was determined by the PIXE and micro-PIXE methods. The mean concentrations of P,
S, Cl, K, Fe, Cu, Zn, and Rb measured by both methods were similar. The latter method also allowed for localization of elements
within lobule territory. It has been found that some elements are more prevalent in the veins (Cl, Fe) and others in the liver
parenchyma (P, Cu, Zn). Moreover, Zn showed the characteristic intralobular distribution. Some methodological aspects of microbeam
application to biological materials were also discussed. 相似文献
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Jerzy Szykuła Cezary Hebda Józef Orpiszewski Klaudia Sagańska 《Biotechnology letters》1991,13(12):917-922
Summary Microbial transformations of neutral fraction (NF) and upgraded neutral fraction (UNF) of Polish tall oil byMycobacterium sp. MB 3683 were performed. Final metabolites and yields were compared to bioconversion of pure -sitosterol. Additionally, origin of a new metabolite —5-androsta-3,6,17-trione was proved by transformation of UNF in the presence of labeled -sitosterol. 相似文献
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Juliusz Perkowski Jerzy Chełkowski Ronald D. Plattner Piotr Goliński 《Mycotoxin Research》1991,7(2):115-120
Maize cobs withFusarium ear rot were collected at 1986 season and five infected byFusarium graminearum were analyzed for presence of triohothecenes and zearalenone. Collected material was subsampled forFusarium damaged kernels and corresponding axial stems and healthy looking kernels. All investigated cobs contained deoxynivalenol (DON) (range 18.0–131.5 mg/kg) and zearalenone (ZEA) (range 0.38–2.17 mg/kg), in four cobs 15-acetyl-deoxynivalenol (15-AcDON) (range 5.2–6.2 mg/kg) was present and two cobs besides three all metabolites contained 3-acetyl-deoxynivalenol (3-AcD0N) (range 0.5–0.8 mg/kg).The average of individual toxins amount in axial stems: in mg/kg was equal to: DON — 110.36, ZEA — 4.57, 15-AcD0N — 16.66, and 3-AcD0N — 1.32.Fusarium damaged kernels contained in average the following amount (mg/kg) of: DON 77.00, ZEA 0.98, 15-AcD0N 3.78 and 3-AcD0N 0.06. Healthy looking kernels contained DON 1.96 mg/kg and ZEA 0.07 mg/kg only. Cooccurrence of 3-AcDON and 15-AcDON in two samples was an interesting finding. The amount of DON in total cob was highly correlated (r = 0.94) with percentage ofFusarium damaged kernels in given ear. 相似文献
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Administration of drugs such as fenfluramine, 20-40 mg/kg, and m-chlorophenylpiperazine (m-CPP), 2.5-5 mg/kg, which release serotonin or activate postsynaptic serotonin receptors, respectively, induced a dramatic decrease in the duodenal content of immunoreactive dynorphin (ir-DYN). The effect was antagonized by cyproheptadine, 1 mg/kg. Similarly, acute administration of the specific serotonin reuptake blockers fluvoxamine, 15 mg/kg, or femoxetine, 10 mg/kg, and 5-hydroxytryptophan (5-HTP), 40-160 mg/kg, evoked a marked decrease in the duodenal content of ir-DYN. A combined administration of fluvoxamine or femoxetine and 5-HTP failed to potentiate the effect of individual treatment. Only a higher dose of fenfluramine, 40 mg/kg, increased the ir-DYN content in the hypothalamus. These results suggest that the brain and gut ir-DYN is independently regulated by the serotonin system and that a serotonin mechanism might stimulate release of the gut dynorphin content. 相似文献
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Summary Using the monotone dependence function (mdf) together with correlation coefficient it was found that the Ma-DNA content as well as total protein content are regularly, linearly, positively and strongly dependent in sister cells (proter-opisthe) ofChilodonella steini. Additionally it was shown that proter-opisthe ordering is irrelevant to Ma-DNA and protein contents.Analysis of sister cell generation times (TG) confirmed the existence of regular, linear, positive and strong codependence.The relations between Ma-DNA and total protein contents, between protein content and TG, and between Ma-DNA content and TG were also described. There is a weak, linear dependence between Ma-DNA and total protein contents. Relations of TG and Ma-DNA content or TG and total protein content are non-linear and not even monotone. Low and high levels of DNA or proteins are connected with long generation times. 相似文献