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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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G M Ka?nova D Markovska D Staneva V E Kagan 《Biulleten' eksperimental'no? biologii i meditsiny》1990,109(1):35-37
Looking for an appropriate model of accelerated aging in vivo we investigated the content of endogenous products of lipid peroxidation (LP) in the rat brain after single or 4 day-lasting intramuscular injection of complex-bind iron (ferum Hausman, 50 mg/kg body weight) like promoter of LP. We found that the single administration of this iron complex fails to induce endogenous LP; after 4 day-application of iron we observed significant increase in content of primary (lipid peroxides) and final (fluorescent) products of LP. Iron-promoted activation of endogenous LP could be abolished by animal pretreatment with the natural antioxidant alpha-tocopherol. The calcium antagonist nifedipine didn't affect the content of endogenous LP products neither alone nor in combination with alpha-tocopherol. 相似文献
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The topography of the auriculotemporal nerve (ATN) root system is the main criterion of this nerve classification. Previous publications indicate that ATN may have between one and five roots. Most common is a one- or two-root variant of the nerve structure. The problem of many publications is the inconsistency of nomenclature which concerns the terms “roots”, “connecting branches”, or “branches” that are used to identify the same structures. This study was performed on 80 specimens (40 adults and 40 fetuses) to propose a classification based on: (i) the number of roots, (ii) way of root division, and (iii) configuration of interradicular fibers that form the ATN trunk. This new classification is a remedy for inconsistency of nomenclature of ATN in the infratemporal fossa. This classification system has proven beneficial when organizing all ATN variants described in previous studies and could become a helpful tool for surgeons and dentists. Examination of ATN from the infratemporal fossa of fetuses (the youngest was at 18 weeks gestational age) showed that, at that stage, the nerve is fully developed. 相似文献
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The course of acute infection of mice with ts mutant or the native strain DNA and the antigens of HSV in brain nerve cells were determined. Virus DNA was detected in brains of all mice in both animal groups while the virus antigens--only in cells of mice infected with the native strain. It can be suggested, therefore, that the ability of ts mutant to replicate in central nervous system of the infected mice is lacking or much lower. The detection of virus nucleic acid 3-5 months after virus infection might indicate a possibility of establishing latent infection. However, ts mutant showed a significantly lower possibility of latency induction, as compared with highly virulent strains. It was found that the mutant ability to induce latent infection was markedly increased when mice were treated with both ts mutant and Depo-Medrol as immunosuppressive agent. This finding shows both a possibility of increase of frequency of latent infections in the state of immunosuppression, and of activation of the latent infection (recurrence of acute form of infection). 相似文献
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Y H Gulcan N Duman A Kumral B Sa?olLebe S Kavuk?u D Er?al M Celilo?lu H Ozkan 《Genetic counseling (Geneva, Switzerland)》2001,12(3):263-267
Cerebrohepatorenal malformation is a rare familial disorder characterized by typical renal lesions combined with Dandy-Walker malformation, and congenital hepatic fibrosis. In this case report, a male premie with the diagnosis of cerebrorenal syndrome or so called Goldston syndrome is presented. Besides the rarity of this syndrome, this case is the second reported patient diagnosed prenatally. 相似文献