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Nalini Santanam MingQing Song Rong Rong Ana A. Murphy Sampath Parthasarathy 《Free radical research》2013,47(12):1315-1321
Endometriosis affects younger women of childbearing age. Atherosclerosis is considered as a disease of the old and increases with the ageing process. Both diseases are characterized by the increased presence of activated macrophages and associated increases in growth promoting activity and the production of inflammatory cytokines. In this review, we propose that oxidative stress and the presence of forms of oxidized low-density lipoprotein (LDL) might contribute to both Atherosclerosis and Endometriosis. 相似文献
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Rômulo Sátiro De Medeiros Ana Maria Camêlo Da Silva Francisco De Sousa Ramalho José Eduardo Serrão Paulo Roberto Cecon 《Biocontrol Science and Technology》2004,14(5):487-498
The daily reproductive rate of Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) fed with Alabama argillacea (Hübner) (Lepidoptera: Noctuidae) larvae was studied at constant temperatures of 20, 23, 25, 28, 30 and 33±0.2°C, relative humidity of 60±10% and photoperiod of L:D 14:10. Daily reproductive rate of P. nigripinus was affected by age of this predator. Each P. nigrispinus female laid 5.3 (20°C) to 19.9 eggs/day (28°C) which developed into 4.3–16.5 nymphs, respectively. Highest daily reproductive rate of P. nigrispinus was recorded at 28 and 30°C for 5–30-day-old females. This predator showed higher daily reproductive rate than its prey A. argillacea at 25°C. It was also able to reproduce at temperatures from 20 to 33°C with maximum daily reproductive rate between 25 and 30°C. These results are important for optimizing mass rearing of P. nigrispinus in the laboratory. 相似文献
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Ana M. Mateus Nicole Gorfinkiel Alfonso Martinez Arias 《Seminars in cell & developmental biology》2009,20(7):877-884
Morphogenesis is the process whereby cells assemble into tissues and organs. Recent studies of this process have revealed heterogeneity of individual cell behaviours that contrasts with the deterministic activity of tissues as a whole. Here we review these observations and suggest that fluctuations and heterogeneities are a central substrate for morphogenesis and that there might exist mechanisms dedicated to the averaging of these fluctuations to ensure robust and reproducible behaviours at the tissue level. 相似文献
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Promiscuous, rolling-circle replication plasmid pMV158 determines tetracycline resistance to its host and can be mobilized by conjugation. Plasmid pLS1 is a deletion derivative of pMV158 that has lost its conjugative mobilization ability. Both plasmids replicate efficiently and are stably inherited in Streptococcus pneumoniae. We have analyzed the effect of pMV158 and pLS1 carriage on the bacterial growth rate. Whereas the parental plasmid does not significantly modify the cell doubling time, pLS1 slows down the growth of the bacterial host by 8-9%. The bases of the differential burden caused by pMV158 and pLS1 carriage are not yet understood. The negligible cost of the pMV158 parental natural plasmid on the host might explain the prevalence of small, multicopy, rolling-circle replication plasmids, even though they lack any selectable trait. 相似文献
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Elsa Leitão Ana Catarina Costa Claudia Brito Lionel Costa Rita Pombinho 《Cell cycle (Georgetown, Tex.)》2014,13(6):928-940
Listeria monocytogenes (Lm) is a human intracellular pathogen widely used to uncover the mechanisms evolved by pathogens to establish infection. However, its capacity to perturb the host cell cycle was never reported. We show that Lm infection affects the host cell cycle progression, increasing its overall duration but allowing consecutive rounds of division. A complete Lm infectious cycle induces a S-phase delay accompanied by a slower rate of DNA synthesis and increased levels of host DNA strand breaks. Additionally, DNA damage/replication checkpoint responses are triggered in an Lm dose-dependent manner through the phosphorylation of DNA-PK, H2A.X, and CDC25A and independently from ATM/ATR. While host DNA damage induced exogenously favors Lm dissemination, the override of checkpoint pathways limits infection. We propose that host DNA replication disturbed by Lm infection culminates in DNA strand breaks, triggering DNA damage/replication responses, and ensuring a cell cycle delay that favors Lm propagation. 相似文献
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Julio Cesar Madureira de-Freitas-Junior Sandra Carvalho Ana M. Dias Patrícia Oliveira Joana Cabral Raquel Seruca Carla Oliveira José Andrés Morgado-Díaz Celso A. Reis Salomé S. Pinho 《PloS one》2013,8(11)
Changes in glycosylation are considered a hallmark of cancer, and one of the key targets of glycosylation modifications is E-cadherin. We and others have previously demonstrated that E-cadherin has a role in the regulation of bisecting GlcNAc N-glycans expression, remaining to be determined the E-cadherin-dependent signaling pathway involved in this N-glycans expression regulation. In this study, we analysed the impact of E-cadherin expression in the activation profile of receptor tyrosine kinases such as insulin receptor (IR) and IGF-I receptor (IGF-IR). We demonstrated that exogenous E-cadherin expression inhibits IR, IGF-IR and ERK 1/2 phosphorylation. Stimulation with insulin and IGF-I in MDA-MD-435 cancer cells overexpressing E-cadherin induces a decrease of bisecting GlcNAc N-glycans that was accompanied with alterations on E-cadherin cellular localization. Concomitantly, IR/IGF-IR signaling activation induced a mesenchymal-like phenotype of cancer cells together with an increased tumor cell invasion capability. Altogether, these results demonstrate an interplay between E-cadherin and IR/IGF-IR signaling as major networking players in the regulation of bisecting N-glycans expression, with important effects in the modulation of epithelial characteristics and tumor cell invasion. Here we provide new insights into the role that Insulin/IGF-I signaling play during cancer progression through glycosylation modifications. 相似文献