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81.
Yichun XuDubois Panagiotis Kavvadas Zela Keuylian Alexandre Hertig Eric Rondeau Christos Chatziantoniou 《Journal of cellular and molecular medicine》2022,26(11):3203
Microvasculature consisting of endothelial cells and pericytes is the main site of injury during antibody‐mediated rejection (ABMR) of renal grafts. Little is known about the mechanisms of activation of pericytes in this pathology. We have found recently that activation of Notch3, a mediator of vascular smooth muscle cell proliferation and dedifferentiation, promotes renal inflammation and fibrosis and aggravates progression of renal disease. Therefore, we studied the pericyte expression of Notch3 in 49 non‐selected renal graft biopsies (32 for clinical cause, 17 for graft surveillance). We analysed its relationship with patients’ clinical and morphological data, and compared with the expression of partial endothelial mesenchymal transition (pEndMT) markers, known to reflect endothelial activation during ABMR. Notch3 was de novo expressed in pericytes of grafts with ABMR, and was significantly correlated with the microcirculation inflammation scores of peritubular capillaritis and glomerulitis and with the expression of pEndMT markers. Notch3 expression was also associated with graft dysfunction and proteinuria at the time of biopsy and in the long term. Multivariate analysis confirmed pericyte expression of Notch3 as an independent risk factor predicting graft loss. These data suggest that Notch3 is activated in the pericytes of renal grafts with ABMR and is associated with poor graft outcome. 相似文献
82.
Panagiotis E. Simitzis Maria A. Charismiadou Basiliki Kotsampasi George Papadomichelakis Eugenia P. Christopoulou Eirini K. Papavlasopoulou Stelios G. Deligeorgis 《Applied animal behaviour science》2009,116(2-4):191-197
The objective of the present experiment was to determine the implications of prenatal undernutrition on the behaviour of juvenile lambs. Dams of one group (C) were fed 100% of the recommended requirements throughout pregnancy, while those of two other groups were fed 50% of the control nutrient allowance during the first 30 days of pregnancy (R1) or 50% of the control nutrient allowance from days 31–100 of pregnancy (R2). Between 2 and 5 months old, behaviour of lambs was tested by the implementation of 2 types of test: isolation and novelty. There were no statistical differences between lamb treatments in escape behaviour and heart rates during isolation test, or the latency to approach a novel or a familiar object in the novelty test in tests conducted at 2, 3, 4 and 5 months of age.Male lambs showed a tendency of turning to the right-hand side of the test pen, irrespective of treatment group, between the age of 2 and 5 months old. A greater proportion of C compared to R1 males turned right at the age of 2 and 5 months old (P < 0.05). Significant differences concerning laterality were found also between C and R1 female lambs at the age of 2 and 4 months old (P < 0.001), between C and R2 male lambs at the age of 2 months old (P < 0.05), between C and R2 female lambs at the age of 4 and 5 months old (P < 0.01), between R1 and R2 male lambs at the age of 2 and 5 months old (P < 0.05) and between R1 and R2 female lambs at the age of 2 months old (P < 0.001).It is concluded that prenatal undernutrition during different periods of pregnancy had no effect on fear-related behaviour, but effect on laterality at the early stages of lamb age between 2 and 5 months old. 相似文献
83.
Panagiota Latsi Panagiotis Pantelidis Dimitris Vassilakis Hiroe Sato Kenneth I Welsh Roland M du Bois 《Respiratory research》2003,4(1):1-5
Background
Genes encoding cytokine mediators are prime candidates for genetic analysis in conditions with T-helper (Th) cell disease driven imbalance. Idiopathic Pulmonary Fibrosis (IPF) is a predominantly Th2 mediated disease associated with a paucity of interferon-gamma (IFN-γ). The paucity of IFN-γ may favor the development of progressive fibrosis in IPF. Interleukin-12 (IL-12) plays a key role in inducing IFN-γ production. The aim of the current study was to assess whether the 1188 (A/C) 3'UTR single nucleotide polymorphism (SNP) in the IL-12 p40 subunit gene which was recently found to be functional and the 5644 (G/A) 3' UTR SNP of the IFN-γ gene were associated with susceptibility to IPF.Methods
We investigated the allelic distribution in these loci in UK white Caucasoid subjects comprising 73 patients with IPF and 157 healthy controls. The SNPs were determined using the polymerase chain reaction in association with sequence-specific primers incorporating mismatches at the 3'-end.Results
Our results showed that these polymorphisms were distributed similarly in the IPF and control groupsConclusion
We conclude that these two potentially important candidate gene single nucleotide polymorphisms are not associated with susceptibility to IPF. 相似文献84.
85.
Konstantinos Stefanidis Dimitris Loutradis Vasiliki Anastasiadou Panagiotis Beretsos Ritsa Bletsa Vasiliki Dinopoulou Kaliopi Lekka Evangelia Elenis Erasmia Kiapekou Stauros Koussoulakos Anastasios Fotinos Aris Antsaklis 《Bio Systems》2009,98(2):122-126
Oxytocin is a nine amino acid peptide involved in a wide spectrum of physiological functions; predominantly those concerning reproduction and differentiation are of interest. Oxytocin receptors are expressed at early developmental stages of mammals, suggesting that oxytocin might be involved in the determination of the germ stem cell line, at the very early stages of mammalian development. In this respect, the proximate aim of the present study was to confirm and further analyze the existence of oxytocin receptors at a very early level of cell commitment, that is, the determination of germ cells derived from embryoid bodies. To achieve our purpose we have cultured mouse embryonic stem cells under conditions inducing formation of embryoid bodies. In this work, ES cells were allowed to aggregate in a novel medium, “Stefanidis medium” from day 0 to day 14 until formed EBs. RNA was isolated from EBs and using RT-PCR we showed that EBs expressed Oct-4, OTR, OT, and DAZL. To demonstrate simultaneous expression immunocytochemistry was preformed, in which EBs showed strong immunoreactivity for both, OTR and DAZL molecular markers. We found that 35% of the cells displayed OTR, using flow cytometry. In addition, this novel medium showed to increase OTR mRNA. We propose, that at least in murine induced embryoid bodies there is simultaneous expression of oxytocin receptors and germ cell markers (DAZL) in many cells (expressing Oct-4). We thus conclude that, the oxytocin might indeed be a molecule playing a leading role in germ cell determination. 相似文献
86.
Romani A Menichetti S Arapitsas P Nativi C Turchetti B Buzzini P 《Bioorganic & medicinal chemistry letters》2005,15(18):4000-4003
The two anomers of O-methyl gluco-2,3-digalloyl esters were synthesized and their antimycotic activity toward yeasts of biomedical importance was evaluated. When used at subinhibitory concentration and regardless of stereochemistry at the anomeric carbon, these compounds enhance the antimycotic activity of Amphotericin B. 相似文献
87.
Defensins and cathelicidins: neutrophil peptides with roles in inflammation, hyperlipidemia and atherosclerosis 总被引:4,自引:0,他引:4
Kougias P Chai H Lin PH Yao Q Lumsden AB Chen C 《Journal of cellular and molecular medicine》2005,9(1):3-10
Atherosclerosis is a disease that begins in fetal life and represents a leading cause of morbidity and mortality associated with significant socioeconomic consequences. A central concept with regard to its pathogenesis is that of endothelial cell dysfunction, which is associated with the release of a large number of mediators secreted by leukocytes that are present in large numbers at the sites of atheroma formation. Neutrophil peptides defensins and cathelicidins are essential elements of the innate immunity and have been present in high concentrations in atherosclerotic plaques in humans. Recently, their role as potential mediators of vascular disease was investigated. Defensins are involved in the lipoprotein metabolism in the vessel wall, favoring LDL and lipoprotein (a) accumulation and modification in the endothelium and the extracellular matrix. They also interfere with the vascular smooth muscle cell function, exhibit prothrombotic activity, and play an inhibitory role in various phases of angiogenesis. Cathelicidins were recently found to enhance endothelial proliferation in cultures, induce functionally significant angiogenesis in animal models, and regulate endothelial cell apoptosis. Further study of these peptides could provide useful insight in the relationship between inflammation and atherosclerosis and is anticipated to have therapeutic and prognostic ramifications. 相似文献
88.
Polykratis A Katsoris P Courty J Papadimitriou E 《The Journal of biological chemistry》2005,280(23):22454-22461
Heparin affin regulatory peptide (HARP) is an 18-kDa secreted growth factor that has a high affinity for heparin and a potent role on tumor growth and angiogenesis. We have previously reported that HARP is mitogenic for different types of endothelial cells and also affects cell migration and differentiation (12). In this study we examined the signaling pathways involved in the migration and tube formation on matrigel of human umbilical vein endothelial cells (HUVEC) induced by HARP. We report for the first time that receptor-type protein-tyrosine phosphatase beta/zeta (RPTPbeta/zeta), which is a receptor for HARP in neuronal cell types, is also expressed in HUVEC. We also document that HARP signaling through RPTPbeta/zeta leads to activation of Src kinase, focal adhesion kinase, phosphatidylinositol 3-kinase, and Erk1/2. Sodium orthovanadate, chondroitin sulfate-C, PP1, wortmannin, LY294002, and U0126 inhibit HARP-mediated signaling and HUVEC migration and tube formation. In addition, RPTPbeta/zeta suppression using small interfering RNA technology interrupts intracellular signals and HUVEC migration and tube formation induced by HARP. These results establish the role of RPTPbeta/zeta as a receptor of HARP in HUVEC and elucidate the HARP signaling pathway in endothelial cells. 相似文献
89.
The objective of this study was to highlight the problems that arise during the reproduction between thin-tailed rams and fat-tailed ewes. At the same time, particular emphasis laid on the influence of sheep breed, sheep age, time after ram introduction and day of the ewe estrus cycle on ram and ewe sexual behaviour. Rams were subjected to sexual performance tests by being individually exposed to 12 ewes for 3 h daily, 19 consecutive days. The 16 rams of the experiment were separated according to their age (9 and 21 months old) and breed (Chios and Karagouniki), and the 96 ewes of Chios fat-tailed breed, were divided by age (9 and 21 months old). The main characteristics of courtship behaviour, like sniffing, nudging, flehmen response and following were recorded and studied in detail. Mature Chios rams, which were the only one with previous experience of Chios ewes, exhibited higher rates of sexual interest per ewe than the other rams (P < 0.05). On the other hand, rams sniffed and nudged more young than mature ewes (P < 0.05), probably due to the fact that young ewes did not express intense symptoms of estrus. Young rams exhibited substandard sexual interest towards mature ewes, when they first came in contact with them (P < 0.05). In general, Karagouniki thin-tailed rams exhibited reduced rates of mating behaviour when they courted with Chios fat-tailed ewes in comparison with Chios rams (P < 0.05). Moreover, as the time after ram introduction passed, the frequency and duration of sexual behaviour components decreased (P < 0.001). Finally, the effect of the day of the experiment was only significant in the case of sniffing, which increased during the first 2 days and then declined and stabilized (P < 0.01). As it was demonstrated, ram age and ram breed played a fundamental role in the exhibition of sexual interest elements. 相似文献
90.