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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53.
Pantos C Malliopoulou V Paizis I Moraitis P Mourouzis I Tzeis S Karamanoli E Cokkinos DD Carageorgiou H Varonos D Cokkinos DV 《Molecular and cellular biochemistry》2003,242(1-2):173-180
It has been recently shown that long-term thyroxine administration increases the tolerance of the heart to ischaemia. The present study investigated whether thyroxine induced cardioprotection involves alterations in the pattern of p38 mitogen activated protein kinase (p38MAPK) and c-Jun NH2-terminal kinases (JNKs) activation during ischaemia-reperfusion. L-thyroxine (T4) was administered in Wistar rats (25 g/100 g/day, subcutaneously) for 2 weeks (THYR), while normal animals served as controls (NORM). NORM and THYR isolated rat hearts were perfused in Langendorff mode and subjected to 10 or 20 min of zero-flow global ischaemia only and also to 20 min of ischaemia followed by 10, 20 or 45 min of reperfusion. Postischaemic recovery of left ventricular developed pressure at 45 min of reperfusion was expressed as % of the initial value. Activation of p38 MAPK and JNKs was assessed at the different times of the experimental setting by standard Western blotting techniques using a dual phospho p38MAPK and phospho JNKs (p46/p54) antibodies. Activation of p38 MAPK was significantly attenuated during ischaemia and reperfusion in thyroxine treated hearts compared to normal hearts. JNKs were found to be activated only during the reperfusion period. The levels of phospho JNKs were found to be lower in thyroxine treated hearts as compared to untreated hearts, though not at a statistically significant level. Postischaemic functional recovery was higher in THYR as compared to NORM, p < 0.05. In summary, in hearts pretreated with thyroxine, p38 MAPK was attenuated during ischaemia and at reperfusion and this was associated with improved postischaemic recovery of function. 相似文献
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Panagiotis D. Dimitriou Nafsika Papageorgiou Christos Arvanitidis Georgia Assimakopoulou Kalliopi Pagou Konstantia N. Papadopoulou Alexandra Pavlidou Paraskevi Pitta Sofia Reizopoulou Nomiki Simboura Ioannis Karakassis 《PloS one》2015,10(10)
A large data set from the Eastern Mediterranean was analyzed to explore the relationship between seawater column variables and benthic community status. Our results showed a strong quantitative link between the seawater column variables (Chlorophyll a and Eutrophication Index) and various indicators describing benthic diversity and community composition. The percentage of benthic opportunistic species increased significantly in the stations with high trophic status of the seawater column and so did the strength of the coupling between values of seawater column and benthic indicators. The Eutrophication Index threshold level of 0.85, separating the “Bad and Poor” from “Moderate to High” conditions could serve as an acceptable critical value above which there is a readily observable change in benthic community composition. 相似文献
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Rupert Seidl Werner Rammer Panagiotis Bellos Eduard Hochbichler Manfred J. Lexer 《Trees - Structure and Function》2010,24(1):139-150
The allocation of carbohydrates from photosynthesis to various plant compartments is a key process in ecophysiology and consequently
an important element in process-based ecosystem modeling. In this study, we tested generalized empirical equations in a widely
applied partitioning concept based on compartment-specific biomass allometries. For an 88-year chronosequence of European
beech (Fagus sylvatica L.) in Austria, we used the individual-based hybrid forest model PICUS v1.4 to compare simulations employing foliage biomass
functions at different levels of generalization against runs with site-specific parameterization and observations. Sensitivities
of the individual tree model were generally in line with the original stand-level partitioning concept and ecological process
understanding. While stand-level leaf area increased with increasing allocation to foliage, net primary productivity showed
no significant response due to saturated radiation interception in the dense chronosequence stands. Strong sensitivities were
revealed at the individual tree level, where favoring allocation to the foliage compartment resulted in increasing asymmetry
of competition and height–diameter relationships. Applying a generalized parameterization based on data from the full range
of continental species distribution resulted in a significant overestimation of mean tree height and subsequently standing
volume stock at the chronosequence. At a lower hierarchical level of generality, however, simulations with a representative
regional parameterization performed satisfactorily compared to model runs using the site-specific allometry. In relation to
common accuracy demands, e.g., in forest management decision support, the study suggests the rejection of a generic parameterization
while corroborating the use of regional generalizations in ecosystem models. 相似文献
60.
Paschalidis A Konstantinos Toumi Imene Moschou N Panagiotis Kalliopi A Roubelakis-Angelakis 《Plant signaling & behavior》2010,5(9):1153-1156
Recently we showed that ABA is at least partly responsible for the induction of the polyamine exodus pathway in Vitis vinifera plants. Both sensitive and tolerant plants employ this pathway to orchestrate stress responses, differing between stress adaptation and programmed cell death. Herein we show that ABA is an upstream signal for the induction of the polyamine catabolic pathway in Vitis vinifera. Thus, amine oxidases are producing H2O2 which signals stomata closure. Moreover, the previously proposed model for the polyamine catabolic pathway is updated and discussed.Key words: plant growth, abscissic acid, polyamines, amine oxidases, signaling, oxidative stress, programmed cell deathWe have shown that tobacco salinity induces an exodus of the polyamine (PA) spermidine (Spd) into the apoplast where it is oxidized by polyamine oxidase (PAO) generating hydrogen peroxide (H2O2). Depending on the size of H2O2, it signals either tolerance-effector genes or the programmed cell death syndrome1 (PCD). PAs are ubiquitous and biologically active molecules. In the recent years remarkable progress has been accomplished regarding the regulation of PAs biosynthesis and catalysis, not only under normal physiological but also under stress conditions.1 The most studied PAs are the diamine Putrescine (Put) and its derivatives the triamine Spd and the tetramine spermine (Spm). They are present in the cells in soluble form (S), or conjugated either to low molecular weight compounds (soluble hydrolyzed form, SH) or to “macro” molecules or cell walls (pellet hydrolyzed form, PH). In higher plants, Put is synthesized either directly from ornithine via ornithine decarboxylase (ODC; EC 4.1.1.17) or indirectly from arginine via arginine decarboxylase (ADC; EC 4.1.1.19). Spd and Spm are synthesized via Spd synthase (EC 2.5.1.16, SPDS) and Spm synthase (EC 2.5.1.22, SPMS), respectively, by sequential addition of aminopropyl groups to Put, catalyzed by S-adenosyl-L-methionine decarboxylase (SAMDC; EC 4.1.1.50).2,3 In plants, PAs are present in the cytoplasm, as well as in cellular organelles.4 Recently it was shown that during stress, they are secreted into the apoplast where they are oxidized by amine oxidases (AOs), such as diamine oxidase for Put (DAO, E.C. 1.4.3.6) and polyamine oxidase (PAO, E.C. 1.4.3.4) for Spd and Spm.1,5,6 Oxidation of PAs generates, amongst other products, H2O21,7,8 which is involved in cell signaling processes coordinated by abscissic acid (ABA),9 but also acts as efficient oxidant and, at high concentration, orchestrates the PCD syndrome.6,10 Two types of PA catabolism by PAO are known in plants: the terminal and the back-conversion pathways. The terminal one takes place in the apoplast, produces except H2O2, 1,3-diaminopropane and an aldehyde depending on the species. On the other hand, the back-conversion pathway is intracellular (cytoplasm and peroxisomes) resulting to the production of H2O2 and the sequential production of Put by Spm via Spd.1,7 Now we have shown that PA exodus also occurs in Vitis vinifera and this phenomenon is at least partially induced by abscissic acid (ABA).11 Thus, exogenous application of ABA results to PA exodus into the apoplast of grapevine. PA is oxidized by an AO resulting to production of H2O2. When the titer of H2O2 is below a threshold, expression of tolerance-effector genes is induced, while when it exceeds this threshold the programmed cell death (PCD) syndrome is induced. 相似文献