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91.
Brain‐derived neurotrophic factor modulates cholesterol homeostasis and Apolipoprotein E synthesis in human cell models of astrocytes and neurons
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92.
Bartacek J Fermoso FG Baldó-Urrutia AM van Hullebusch ED Lens PN 《Journal of industrial microbiology & biotechnology》2008,35(11):1465-1474
The influence of cobalt speciation on the toxicity of cobalt to methylotrophic methanogenesis in anaerobic granular sludge
was investigated. The cobalt speciation was studied with three different media that contained varying concentrations of complexing
ligands [carbonates, phosphates and ethylenediaminetetraacetic acid (EDTA)]. Three fractions (nominal added, dissolved and
free) of cobalt were determined in the liquid media and were correlated with data from batch toxicity experiments. The average
concentration of cobalt that was required for 50% inhibition of methanogenic activity (IC50) for free Co2+ in the three sets of measurements was 13 μmol/L with a standard deviation of 22% and a similarity of 72% between the data
obtained in the three different media for the range of cobalt concentrations investigated. The standard deviation of the IC50 for the other two fractions was much higher, i.e. 85 and 144% for the added cobalt and dissolved cobalt, respectively, and
the similarity was almost 0% for both fractions. Complexation (and precipitation) with EDTA, phosphates and carbonates was
shown to decrease the toxicity of cobalt on methylotrophic methanogenesis. The free cobalt concentration is proposed to be
the key parameter to correlate with cobalt toxicity. Thus, the toxicity of cobalt to granular sludge can be estimated based
on the equilibrium-free cobalt concentration. 相似文献
93.
Nijholt IM Dolga AM Ostroveanu A Luiten PG Schmidt M Eisel UL 《Cellular signalling》2008,20(10):1715-1724
In diverse neuronal processes ranging from neuronal survival to synaptic plasticity cyclic adenosine monophosphate (cAMP)-dependent signaling is tightly connected with the protein kinase B (PKB)/Akt pathway but the precise nature of this connection remains unknown. In the current study we investigated the effect of two mainstream pathways initiated by cAMP, cAMP-dependent protein kinase (PKA) and exchange proteins directly activated by cAMP (Epac1 and Epac2) on PKB/Akt phosphorylation in primary cortical neurons and HT-4 cells. We demonstrate that PKA activation leads to a reduction of PKB/Akt phosphorylation, whereas activation of Epac has the opposite effect. This effect of Epac on PKB/Akt phosphorylation was mediated by Rap activation. The increase in PKB/Akt phosphorylation after Epac activation could be blocked by pretreatment with Epac2 siRNA and to a somewhat smaller extent by Epac1 siRNA. PKA, PKB/Akt and Epac were all shown to establish complexes with neuronal A-kinase anchoring protein150 (AKAP150). Interestingly, activation of Epac increased phosphorylation of PKB/Akt complexed to AKAP150. From experiments using PKA-binding deficient AKAP150 and peptides disrupting PKA anchoring to AKAPs, we conclude that AKAP150 acts as a key regulator in the two cAMP pathways to control PKB/Akt phosphorylation. 相似文献
94.
Bjrn Berg Amalia Virzo De Santo Flora Angela Rutigliano Angelo Fierro Gunnar Ekbohm 《Acta Oecologica》2003,24(5-6):295-302
The decomposition dynamics of four types of needle litter and three types of leaf litter were followed for 3 years at two very contrasting coniferous forest systems, a nutrient-rich silver fir (Abies alba Mill.) forest in south Italy (Monte Taburno) and a nutrient-poor Scots pine (Pinus sylvestris L.) forest in central Sweden (Jädraås). Decomposition of the same litter type at the two sites did not differ in the early stages but proceeded further at the nutrient-rich forest site than at the nutrient-poor one. Limit values for decomposition were calculated and the differences for the same litter type between the two contrasting coniferous systems were investigated. At both sites six of the seven litter types gave significant (asymptotic) limit values for decomposition, which varied with litter type. For four litter types out of six the limit values differed significantly between the two sites and were always higher at the nutrient-rich site (Monte Taburno). Using all available data for litters incubated at the two sites revealed that at the nutrient-poor site (Jädraås) there was a significant negative relationship between litter N levels and limit values and there was also a significant negative relationship between initial concentrations of heavy metals (e.g. Zn, Cd, Cu) and limit values. In contrast, at the site Monte Taburno, rich in nutrients and in heavy metals, there was no such relationship. 相似文献
95.
Luca Vitale Paul Di Tommasi Carmen Arena Michele Riondino Annachiara Forte Angelo Verlotta Angelo Fierro Amalia Virzo De Santo Amodio Fuggi Vincenzo Magliulo 《Acta Physiologiae Plantarum》2009,31(2):331-341
The effect of water shortage on growth and gas exchange of maize grown on sandy soil (SS) and clay soil was studied. The lower
soil water content in the SS during vegetative growth stages did not affect plant height, above-ground biomass, and leaf area
index (LAI). LAI reduction was observed on the SS during the reproductive stage due to early leaf senescence. Canopy and leaf
gas exchanges, measured by eddy correlation technique and by a portable photosynthetic system, respectively, were affected
by water stress and a greater reduction in net photosynthetic rate (A
N) and stomatal conductance (g
s) was observed on SS. Chlorophyll and carotenoids content was not affected by water shortage in either condition. Results
support two main conclusions: (1) leaf photosynthetic capacity was unaffected by water stress, and (2) maize effectively endured
water shortage during the vegetative growth stage. 相似文献
96.
Stephen J. Peterson Dong Hyun Kim Ming Li Vincenzo Positano Luca Vanella Luigi F. Rodella Francesco Piccolomini Nitin Puri Amalia Gastaldelli Claudia Kusmic Antonio L'Abbate Nader G. Abraham 《Journal of lipid research》2009,50(7):1293-1304
We examined mechanisms by which L-4F reduces obesity and diabetes in obese (ob) diabetic mice. We hypothesized that L-4F reduces adiposity via increased pAMPK, pAKT, HO-1, and increased insulin receptor phosphorylation in ob mice. Obese and lean mice were divided into five groups: lean, lean-L-4F-treated, ob, ob-L-4F-treated, and ob-L-4F-. Food intake, insulin, glucose adipocyte stem cells, pAMPK, pAKT, CB1, and insulin receptor phosphorylation were determined. Subcutaneous (SAT) and visceral adipose tissue (VAT) were determined by MRI and hepatic lipid content by magnetic resonance spectroscopy. SAT and VAT volumes decreased in ob-L-4F-treated animals compared with control. L-4F treatment decreased hepatic lipid content and increased the numbers of small adipocytes (P < 0.05) and phosphorylation of insulin receptors. L-4F decreased CB1 in SAT and VAT and increased pAKT and pAMPK in endothelium. L-4F-mediated improvement in endothelium was prevented by LY294002. Inhibition of pAKT and pAMPK by LY294002 was associated with an increase in glucose levels. Upregulation of HO-1 by L-4F produced adipose remodeling and increased the number of small differentiated adipocytes. The anti-obesity effects of L-4F are manifested by a decrease in visceral fat content with reciprocal increases in adiponectin, pAMPK, pAKT, and phosphorylation of insulin receptors with improved insulin sensitivity. LY294002相似文献
97.
Background
Microarray technology is increasingly used to identify potential biomarkers for cancer prognostics and diagnostics. Previously, we have developed the iterative Bayesian Model Averaging (BMA) algorithm for use in classification. Here, we extend the iterative BMA algorithm for application to survival analysis on high-dimensional microarray data. The main goal in applying survival analysis to microarray data is to determine a highly predictive model of patients' time to event (such as death, relapse, or metastasis) using a small number of selected genes. Our multivariate procedure combines the effectiveness of multiple contending models by calculating the weighted average of their posterior probability distributions. Our results demonstrate that our iterative BMA algorithm for survival analysis achieves high prediction accuracy while consistently selecting a small and cost-effective number of predictor genes. 相似文献98.
99.
Rose G Romeo G Dato S Crocco P Bruni AC Hervonen A Majamaa K Sevini F Franceschi C Passarino G;GEnetics of Healthy Ageing Project Consortium 《PloS one》2010,5(10):e13395
Tissue specific somatic mutations occurring in the mtDNA control region have been proposed to provide a survival advantage. Data on twins and on relatives of long-lived subjects suggested that the occurrence/accumulation of these mutations may be genetically influenced. To further investigate control region somatic heteroplasmy in the elderly, we analyzed the segment surrounding the nt 150 position (previously reported as specific of Leukocytes) in various types of leukocytes obtained from 195 ultra-nonagenarians sib-pairs of Italian or Finnish origin collected in the frame of the GEHA Project. We found a significant correlation of the mtDNA control region heteroplasmy between sibs, confirming a genetic influence on this phenomenon. Furthermore, many subjects showed heteroplasmy due to mutations different from the C150T transition. In these cases heteroplasmy was correlated within sibpairs in Finnish and northern Italian samples, but not in southern Italians. This suggested that the genetic contribution to control region mutations may be population specific. Finally, we observed a possible correlation between heteroplasmy and Hand Grip strength, one of the best markers of physical performance and of mortality risk in the elderly. Our study provides new evidence on the relevance of mtDNA somatic mutations in aging and longevity and confirms that the occurrence of specific point mutations in the mtDNA control region may represent a strategy for the age-related remodelling of organismal functions. 相似文献
100.
Design and expression of peptides with antimicrobial activity against Salmonella typhimurium
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Amalia Porta Anna Maria Petrone Silvana Morello Ilaria Granata Francesca Rizzo Domenico Memoli Alessandro Weisz Bruno Maresca 《Cellular microbiology》2017,19(2)
We showed previously that insertion of Synechocystis Δ12‐desaturase in salmonella's membrane alters membrane physical state (MPS), followed by the expression of stress genes causing inability to survive within murine macrophages (MΦ). Recently, we showed that expression of one membrane lipid domain (MLD) of Δ12‐desaturase (ORF200) interferes with salmonella MPS, causing loss of virulence in mice and immunoprotection. Here, we postulate that an α‐antimicrobial peptide (α‐AMP) intercalates within membrane lipids, and depending on its amino acid sequence, it does so within specific key sensors of MLD. In this study, we choose as target for a putative synthetic AMP, PhoP/PhoQ, a sensor that responds to low Mg2+ concentration. We synthesised a modified DNA fragment coding for an amino acid sequence (NUF) similar to that fragment and expressed it in salmonella typhimurium. We showed that the pattern of gene expression controlled by PhoP/PhoQ highlights dysregulation of pathways involving phospholipids biosynthesis, stress proteins and genes coding for antigens. RNA‐Seq of strain expressing ORF200 showed that the pattern of those genes is also altered here. Accumulation of NUF conferred temporary immunoprotection. This represents a powerful procedure to address synthetic α‐AMPs to a specific MLD generating live non‐virulent bacterial strains. 相似文献