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581.
Vesna Bucan Kerstin Reimers Claudia Yu Choi Mau-Thek Eddy Peter M. Vogt 《Cellular & molecular biology letters》2010,15(2):296-310
Lifeguard (LFG) is an anti-apoptotic protein that inhibits Fas-mediated death in tumour cells. However, the molecular function
of human LFG in the carcinogenesis of human breast cells is uncertain. We studied the expression and function of endogenous
LFG in four breast cancer cell lines (MCF-7, MDA-MB-231, T-47D and HS 578T), a human breast epithelial cell line (HS 578Bst),
and in healthy and cancerous breast tissues. Molecular (Western blot and RT-PCR) and immunohistochemical techniques were used
to investigate the LFG expression. To investigate the breast cancer cell proliferation in the presence of Fas, we performed
fluorescent cell viability assays. The possible association of Fas with LFG was analyzed by immunofluorescence microscopy.
In this paper, we provide convincing evidence that LFG is overexpressed in several human breast cancer cell lines. More importantly,
we found that the LFG expression correlates with high tumour grades in primary breast tumours. Finally, we demonstrated that
Fas sensitivity is reduced in breast cancer cell lines expressing LFG. Our results indicated that LFG is strongly expressed
in breast cancer epithelial cells. Moreover, the overexpression of LFG correlated with tumour grade and reduced Fas sensitivity.
Our findings support the idea that LFG may have a role in the downregulation of apoptosis in breast cancer cells. 相似文献
582.
Danica Pavlović Branka Petković Srećko Ćurčić Dajana Todorović Nikola Vesović Dejan Pantelić Vesna Perić‐Mataruga 《Entomologia Experimentalis et Applicata》2016,160(2):188-194
The aim of this study was to investigate the effects of a static magnetic field on six behavioral parameters (travel distance, average speed while in motion, travel distance of the head, body rotations, time in movement, and immobility time) of the ground beetle Laemostenus (Pristonychus) punctatus (Dejean) (Coleoptera: Carabidae). Adults of this troglophilic and guanophilic beetle were randomly divided into two groups, the first exposed to a static magnetic field of 110 mT for 5 h, and the second a control group. Beetle behavior after these 5 h was monitored in an open‐field test for 12 min and analyzed using ANY‐maze software. Exposure to a static magnetic field of 110 mT increased motor activity (travel distance and average speed while in motion) in the first 4 min. After that there were no significant differences. We conclude that the applied static magnetic field affects motor activity of adult specimens of L. (P.) punctatus, and we discuss the mechanism, possibly through acting on the control centers responsible for orientation and movement. 相似文献
583.
Martins AH Alves JM Perez D Carrasco M Torres-Rivera W Eterović VA Ferchmin PA Ulrich H 《PloS one》2012,7(2):e30755
Background
Kinins, with bradykinin and des-Arg9-bradykinin being the most important ones, are pro-inflammatory peptides released after tissue injury including stroke. Although the actions of bradykinin are in general well characterized; it remains controversial whether the effects of bradykinin are beneficial or not. Kinin-B2 receptor activation participates in various physiological processes including hypotension, neurotransmission and neuronal differentiation. The bradykinin metabolite des-Arg9-bradykinin as well as Lys-des-Arg9-bradykinin activates the kinin-B1 receptor known to be expressed under inflammatory conditions. We have investigated the effects of kinin-B1 and B2 receptor activation on N-methyl-D-aspartate (NMDA)-induced excitotoxicity measured as decreased capacity to produce synaptically evoked population spikes in the CA1 area of rat hippocampal slices.Principal Findings
Bradykinin at 10 nM and 1 µM concentrations triggered a neuroprotective cascade via kinin-B2 receptor activation which conferred protection against NMDA-induced excitotoxicity. Recovery of population spikes induced by 10 nM bradykinin was completely abolished when the peptide was co-applied with the selective kinin-B2 receptor antagonist HOE-140. Kinin-B2 receptor activation promoted survival of hippocampal neurons via phosphatidylinositol 3-kinase, while MEK/MAPK signaling was not involved in protection against NMDA-evoked excitotoxic effects. However, 100 nM Lys-des-Arg9-bradykinin, a potent kinin-B1 receptor agonist, reversed bradykinin-induced population spike recovery. The inhibition of population spikes recovery was reversed by PD98059, showing that MEK/MAPK was involved in the induction of apoptosis mediated by the B1 receptor.Conclusions
Bradykinin exerted protection against NMDA-induced excitotoxicity which is reversed in the presence of a kinin-B1 receptor agonist. As bradykinin is converted to the kinin-B1 receptor metabolite des-Arg9-bradykinin by carboxypeptidases, present in different areas including in brain, our results provide a mechanism for the neuroprotective effect in vitro despite of the deleterious effect observed in vivo. 相似文献584.
Roksandic M Mihailović D Mercier N Dimitrijević V Morley MW Rakočević Z Mihailović B Guibert P Babb J 《Journal of human evolution》2011,61(2):186-196
Neandertals and their immediate predecessors are commonly considered to be the only humans inhabiting Europe in the Middle and early Late Pleistocene. Most Middle Pleistocene western European specimens show evidence of a developing Neandertal morphology, supporting the notion that these traits evolved at the extreme West of the continent due, at least partially, to the isolation produced by glacial events. The recent discovery of a mandible, BH-1, from Mala Balanica (Serbia), with primitive character states comparable with Early Pleistocene mandibular specimens, is associated with a minimum radiometric date of 113 + 72 − 43 ka. Given the fragmented nature of the hemi-mandible and the fact that primitive character states preclude assignment to a species, the taxonomic status of the specimen is best described as an archaic Homo sp. The combination of primitive traits and a possible Late Pleistocene date suggests that a more primitive morphology, one that does not show Neandertal traits, could have persisted in the region. Different hominin morphologies could have survived and coexisted in the Balkans, the “hotspot of biodiversity.” This first hominin specimen to come from a secure stratigraphic context in the Central Balkans indicates a potentially important role for the region in understanding human evolution in Europe that will only be resolved with more concentrated research efforts in the area. 相似文献
585.
Gaspar T Labor M Jurić I Dumancić D Ilakovac V Heffer M 《Collegium antropologicum》2011,35(Z1):163-167
The recognition of basic emotions in everyday communication involves interpretation of different visual and auditory clues. The ability to recognize emotions is not clearly determined as their presentation is usually very short (micro expressions), whereas the recognition itself does not have to be a conscious process. We assumed that the recognition from facial expressions is selected over the recognition of emotions communicated through music. In order to compare the success rate in recognizing emotions presented as facial expressions or in classical music works we conducted a survey which included 90 elementary school and 87 high school students from Osijek (Croatia). The participants had to match 8 photographs of different emotions expressed on the face and 8 pieces of classical music works with 8 offered emotions. The recognition of emotions expressed through classical music pieces was significantly less successful than the recognition of emotional facial expressions. The high school students were significantly better at recognizing facial emotions than the elementary school students, whereas girls were better than boys. The success rate in recognizing emotions from music pieces was associated with higher grades in mathematics. Basic emotions are far better recognized if presented on human faces than in music, possibly because the understanding of facial emotions is one of the oldest communication skills in human society. Female advantage in emotion recognition was selected due to the necessity of their communication with the newborns during early development. The proficiency in recognizing emotional content of music and mathematical skills probably share some general cognitive skills like attention, memory and motivation. Music pieces were differently processed in brain than facial expressions and consequently, probably differently evaluated as relevant emotional clues. 相似文献
586.
587.
Patrick Brunet-Lecomte Sophie Montuire Vesna Dimitrijevic 《Pal?ontologische Zeitschrift》2001,75(2):189-196
A general morphometrical analysis of the M1 was conducted to identify the subterranean vole species found in Upper Pleistocene localities from Serbia and Montenegro,
and to clarify the systematic position and the phylogenetic relationships between the different species in the Balkans. From
the different localities studied, we can assign one population toMicrotus (Terricola) thomasi and the others to theM. (T.) subterraneus group. This study suggests thatM. (T.) grafi can be considered as a chronological sub-species ofM. (T.) subterraneus or as a different but phylogenetically very close species. 相似文献
588.
To assess local differentiation in host preference, a two-choice test was performed on first-instar gypsy moth larvae originating from an oak and locust-tree forest. More than 40 generations feeding on locust-tree leaves, rich in alkaloids, led to non-efficient discrimination of host leaves in larvae from a locust-tree forest. Possible causes of observed population differences are discussed in the present paper. 相似文献
589.
Vesna Hadi-Takov ukalovi 《Physiologia plantarum》1990,80(2):238-242
Glutamate dehydrogenase (EC 1.4.1.3) activity was assayed in homogenates of maize ( Zea mays L. inbred lines Oh43 and Oh43o2 ) endosperm during development. During the period 20–35 days after pollination anabolic (aminative) activities were higher than catabolic (deaminating) ones. In order to study the regulation of GDH activity, glutamine or glutamate were injected into the ear peduncle before sample harvesting. The amination and deamination reactions showed similar behaviour with different nitrogen sources: glutamine increased, whereas glutamate decreased, both aminative and deaminative reactions. Partially purified enzyme was active with NADH and NADPH in a ratio 9:1. In Tris-HCl buffer a broad optimum at pH 7.6–8.9 and pH 6.8–8.9 was observed with NADH and NADPH, respectively, NADH activity was activated by Ca2+ . Saturation curves for (NH4 )2 SO4 and NADH showed normal Michaelis-Menten kinetics in the presence of 1 m M Ca2+ , but substrate inhibition occurred without Ca2+ . The enzyme was inactivated by EDTA. The effect of EDTA was reversed by Ca2+ and Mn2+ , but not by Cu2+ and Mg2+ . 相似文献
590.
Kasapović J Pejić S Todorović A Stojiljković V Pajović SB 《Cell biochemistry and function》2008,26(6):723-730
Oxidative stress is considered to be implicated in the pathophysiology of breast cancers. In this study we investigated the level of oxidative stress and antioxidant (AO) status in the blood of breast cancer patients of different ages. The level of lipid hydroperoxides (LP) was measured in blood plasma and the activities of copper, zinc superoxide dismutase (CuZnSOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) enzymes, as well as the level of total glutathione (GSH) and CuZnSOD protein were measured in blood cells of breast cancer patients and age-matched healthy subjects. Our results showed that breast carcinoma is related to increase of lipid peroxidation in plasma with concomitant decrease of AO defense capacity in blood cells, which becomes more pronounced during aging of the patients. Suppression of CuZnSOD activity related to breast cancer is most likely caused by decreased de novo synthesis of this enzyme. Similar patterns of suppression in CuZnSOD and CAT activities related to aging were recorded both in controls and patients. Age-related decrease in CuZnSOD activity seems not to be caused by altered protein levels of this enzyme. Suppression of AO enzymes associated with breast cancer and aging is most likely the cause of increased levels of reactive oxygen species (ROS). Our results indicate significant role of oxidative-induced injury in the breast carcinogenesis, particularly during the later stages of aging. Overall, our data support the importance of endogenous AOs in the etiology of breast cancer across all levels of predicted risk. 相似文献