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911.
Andréa Baldasso-Zanon Andrew Oliveira Silva Nayara Franco Rafael V. Picon Guido Lenz Patrícia Luciana da Costa Lopez Eduardo C. Filippi-Chiela 《Journal of cellular biochemistry》2024,125(2):e30517
Colorectal cancer (CRC) is the third most common and deadliest cancer globally. Regimens using 5-fluorouracil (5FU) and Oxaliplatin (OXA) are the first-line treatment for CRC, but tumor recurrence is frequent. It is plausible to hypothesize that differential cellular responses are triggered after treatments depending on the genetic background of CRC cells and that the rational modulation of cell tolerance mechanisms like autophagy may reduce the regrowth of CRC cells. This study proposes investigating the cellular mechanisms triggered by CRC cells exposed to 5FU and OXA using a preclinical experimental design mimicking one cycle of the clinical regimen (i.e., 48 h of treatment repeated every 2 weeks). To test this, we treated CRC human cell lines HCT116 and HT29 with the 5FU and OXA, combined or not, for 48 h, followed by analysis for two additional weeks. Compared to single-drug treatments, the co-treatment reduced tumor cell regrowth, clonogenicity and stemness, phenotypes associated with tumor aggressiveness and poor prognosis in clinics. This effect was exerted by the induction of apoptosis and senescence only in the co-treatment. However, a week after treatment, cells that tolerated the treatment had high levels of autophagy features and restored the proliferative phenotype, resembling tumor recurrence. The pharmacologic suppression of early autophagy during its peak of occurrence, but not concomitant with chemotherapeutics, strongly reduced cell regrowth. Overall, our experimental model provides new insights into the cellular mechanisms that underlie the response and tolerance of CRC cells to 5FU and OXA, suggesting optimized, time-specific autophagy inhibition as a new avenue for improving the efficacy of current treatments. 相似文献
912.
Elena Motivans vara Valentin tefan Esther Sossai Reinart Feldmann Dianne Joy Aguilon Anna Bontsutsnaja Anna EVojtk Isabel C. Kilian Piret Lang Marilin Mtlep Elisabeth Prangel MariLiis Viljur Tiffany M. Knight Lena Neuenkamp 《Ecology and evolution》2021,11(23):16909
In the face of global pollinator decline, extensively managed grasslands play an important role in supporting stable pollinator communities. However, different types of extensive management may promote particular plant species and thus particular functional traits. As the functional traits of flowering plant species (e.g., flower size and shape) in a habitat help determine the identity and frequency of pollinator visitors, they can also influence the structures of plant−pollinator interaction networks (i.e., pollination networks). The aim of this study was to examine how the type of low‐intensity traditional management influences plant and pollinator composition, the structure of plant−pollinator interactions, and their mediation by floral and insect functional traits. Specifically, we compared mown wooded meadows to grazed alvar pastures in western Estonia. We found that both management types fostered equal diversity of plants and pollinators, and overlapping, though still distinct, plant and pollinator compositions. Wooded meadow pollination networks had significantly higher connectance and specialization, while alvar pasture networks achieved higher interaction diversity at a standardized sampling of interactions. Pollinators with small body sizes and short proboscis lengths were more specialized in their preference for particular plant species and the specialization of individual pollinators was higher in alvar pastures than in wooded meadows. All in all, the two management types promoted diverse plant and pollinator communities, which enabled the development of equally even and nested pollination networks. The same generalist plant and pollinator species were important for the pollination networks of both wooded meadows and alvar pastures; however, they were complemented by management‐specific species, which accounted for differences in network structure. Therefore, the implementation of both management types in the same landscape helps to maintain high species and interaction diversity. 相似文献
913.
Esther Pozas Jordi Ballabriga Anna M. Planas Isidro Ferrer 《Developmental neurobiology》1997,33(3):232-246
c-fos and c-jun mRNA induction and c-Fos and c-Jun protein expression were examined in the brains of adult rats subjected to systemic kainic acid (KA) injection at convulsant doses. Induction of c-fos and c-jun mRNA, as seen with in situ hybridization, occurred in the piriform and entorhinal cortices, neocortex, amygdala, hippocampus, dentate gyrus, and discrete thalamic nuclei. This was followed by c-Fos protein expression, as revealed with immunohistochemistry, in the same regions. However, the distribution of c-Jun protein expression differed depending on the antibody used. The distribution of cells immunostained with the antibody c-Jun (AB-1) was similar to that of c-jun mRNA, but the distribution of cells immunostained with the antibody c-Jun/AP1 (N) was restricted to a few neurons in the pyramidal cell layer of CA1 and CA3, layer II of the piriform and entorhinal cortices, basal amygdala, and discrete thalamic nuclei. Although the regional distribution of c-Fos- and c-Jun-immunoreactive cells in the hippocampus, layer II of the entorhinal and piriform cortices, basal amygdala, and discrete thalamic nuclei matched the distribution of cells committed to dying, c-Fos- and c-Jun-immunoreactive cells in the neocortex and dentate gyrus survived. Therefore, the present data show that c-fos and c-jun are not predictors of either cell death or survival, but rather, markers of cells sensitive to KA excitotoxicity. Western blots to c-Fos showed a double band at p62 in samples containing the hippocampus and entorhinal and piriform cortices (hip samples) and in samples containing the neocortex (cortex samples). The upper band was abolished following preincubation of the samples with alkaline phosphatase, thus suggesting c-Fos phosphorylation. Western blots to c-Jun (AB-1) showed a single band at about p39 in hip and cortex. However, Western blots to c-Jun/AP1 (N) identified two bands. One band at about p39 was seen in control rats and the cortex of KA-treated rats. Another band at p26 was observed only in hip samples of KA-treated rats. In addition, decreased c-Jun N-terminal kinase 1 (JNK-1) expression, as revealed on Western blots, was coincidental with the appearance of the p26 c-Jun-immunoreactive band in KA-treated rats. These results show that c-Fos and different Jun-related antigens are expressed following KA excitotoxicity, and that posttranslational modifications involving phosphorylation of c-Fos and Jun(s) may occur following KA injection. These results also stress the necessity of examining the composition of Fos and Jun-related antigens and the metabolic state of Fos and Jun(s) in different experimental models of nervous system injury. © 1997 John Wiley & Sons, Inc. J Neurobiol 33: 232–246, 1997 相似文献
914.
Pedro Moral Esther Esteban Sergi Vives Neus Valveny Domingo I. Toja Emilio Gonzalez-Reimers 《American journal of physical anthropology》1997,102(3):337-349
Data on six protein polymorphisms (19 alleles) from the human population of Tenerife are presented and discussed along with other classical markers in relation to the origin of the Canarians. Genetic influences from three population groups were considered: the Iberians, and the Berbers and non-Berbers (Arabs) from north Africa. The systems examined show the Tenerife population lies within the limits of variation described for various Iberian groups, with a slight tendency towards the characteristics of north African populations. When blood groups, red cell enzymes and serum protein data were considered, the similarity of the Canary population to Iberians seems strengthened (70% estimated contribution of Iberian peninsula genes to the present-day Canarian pool), while some relation with north African groups is shown. Genetic distances between Canarians and Arabs and Canarians and Berbers are lower than those between the two north African groups, indicating a relative and comparable contribution of each to the present-day gene pool of the Canarian population. The Arab contribution could be attributable to the slaves who were introduced to these islands after the conquest in the 15th century, while the Berber contribution could be the remnants of the extinct aboriginal peoples of the islands (Guanches) or a more recent immigration due to slavery. Genetic data do not allow us to distinguish between these two possibilities. Am. J. Phys. Anthropol. 102:337–349, 1997. © 1997 Wiley-Liss, Inc. 相似文献
915.
Different species of ciliates (Paramecium biaurelia, Loxodes striatus, Tetrahymena thermophila) have been taken as model systems to study the effects of extremely low-frequency electromagnetic fields (50 Hz, 0.5–2.0 mT) on the cellular level. A dose-dependent increase in the mean swimming velocity and a decrease in the linearity of cell tracks were observed in all wild-type cells. In contrast, field-exposure did not increase the number of directional turns of the Paramecium tetraurelia pawn mutant (d4–500r), which is characterized by defective Ca2+-channels. The described changes indicate a direct effect of low frequency electromagnetic fields on the transport mechanisms of the cell membrane for ions controlling the motile activity of cilia. Bioelectromagnetics 18:491–498, 1997. © 1997 Wiley-Liss, Inc. 相似文献
916.
Priya A. Debisarun Katharina L. Gssling Ozlem Bulut Gizem Kilic Martijn Zoodsma Zhaoli Liu Marina Oldenburg Nadine Rüchel Bowen Zhang Cheng-Jian Xu Patrick Struycken Valerie A. C. M. Koeken Jorge Domínguez-Andrs Simone J. C. F. M. Moorlag Esther Taks Philipp N. Ostermann Lisa Müller Heiner Schaal Ortwin Adams Arndt Borkhardt Jaap ten Oever Reinout van Crevel Yang Li Mihai G. Netea 《PLoS pathogens》2021,17(10)
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920.
Molecular testing of BRAF,RAS and TERT on thyroid FNAs with indeterminate cytology improves diagnostic accuracy
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L. Depaepe V. Lapras M.‐L. Denier F. Borson‐Chazot J.‐C. Lifante J. Lopez 《Cytopathology》2017,28(6):482-487