The Aspergillus nidulans carnitine carrier encoded by the acuH gene is exclusively located in the mitochondria

The location of the Aspergillus nidulans carnitine/acyl-carnitine carrier (ACUH) was studied. ACUH with a His-tag at its N-terminus was over-expressed in Escherichia coli and purified by Ni(2+) affinity chromatography. The purified protein was utilised to raise polyclonal antibodies which were characterised by Western blotting. For localisation studies A. nidulans T1 strain, that contains the acuH gene under control of the strong promoter alcA(p), was derived. Results obtained demonstrate the exclusively mitochondrial localisation of ACUH and therefore exclude the targeting of the acuH gene product to the peroxisomal membrane.     

Synthesis,electronic, and spectral properties of novel geranylated chalcone derivatives: a theoretical and experimental study

Novel chalcone derivatives with different substituents attached to A and B-rings: hydroxyl, methoxyl, geranyl, and prenyl groups were synthesized. The obtained compounds were characterized by NMR, HRMS, UV-Vis, IR, and MS. The theoretical analysis was carried out in all the compounds using density functional theory (DFT) with the B3LYP, PBE0, and M06-2X functionals in combination with the 6-311G(d,p) Pople-type basis set. The excited state properties were calculated by time dependent density functional theory (TD-DFT) using the same methodology applied for the ground state properties. The calculated vertical absorption wavelengths (λ_max) in gas phase and in ethanol as a solvent are consistent with the experimental ones, being the TD-DFT:B3LYP/6-311G(d,p) and PCM-TD-DFT:PBE0/6-311G(d,p) the best methodologies for these calculations with good approximation to the experimental values. The calculated reorganization energies indicated that, the four chalcone derivatives present an electron transfer character due to the smaller registered values. From these parameters it is proposed that these show an n-type semiconductor character. The localization of the frontier orbitals (HOMO and LUMO) shows that only the compound containing a hydroxyl group on the A-ring displays a marked delocalization favoring the charge-transfer process in this system. The HOMO-LUMO gap energies indicate that the inclusion of different donor groups in the rings does not improve the obtained values for this property.

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Graphical Abstract Relationship between spectroscopic and geometrical properties of chalcones were carried out using quantum-chemical calculations and compared with experimental values.

     

Psychological distress and personality factors in takotsubo cardiomyopathy

Background

Takotsubo cardiomyopathy (TCC) is a transient condition characterised by severe left ventricular dysfunction combined with symptoms and signs mimicking myocardial infarction. Emotional triggers are common, but little is known about the psychological background characteristics of TCC. This study examined whether patients with TTC have higher levels of psychological distress (depressive symptoms, perceived stress, general anxiety), illness-related anxiety and distinct personality factors compared with healthy controls and patients with heart failure.

Methods and Results

Patients with TCC (N = 18; mean age 68.3 ± 11.7 years, 77.8?% women) and two comparison groups (healthy controls: N = 19, age 60.0 ± 7.6, 68.4?% women and patients with chronic heart failure: N = 19, age 68.8 ± 10.1, 68.4?% women) completed standardised questionnaires to measure depression (PHQ?9), perceived stress (PSS-10), general anxiety (GAD-7), illness-related anxiety (WI-7) and personality factors (NEO-FFI and DS-14). Psychological measures were obtained at 23 ± 18 months following the acute TTC event. Results showed that patients with TCC had higher levels of depressive symptoms (5.2 ± 5.2 vs. 2.5 ± 2.4, p = 0.039) and illness-related anxiety (2.1 ± 1.7 vs. 0.7 ± 1.3, p = 0.005) compared with healthy controls. Patients with TCC did not display significantly elevated perceived stress (p = 0.072) or general anxiety (p = 0.170). Regarding personality factors, levels of openness were lower in TCC compared with healthy controls (34.2 ± 4.3 vs. 38.2 ± 5.6, p = 0.021). No differences between TCC and heart failure patients were found regarding the psychological measures.

Conclusions

TCC is associated with higher levels of depressive symptoms, more illness-related anxiety and less openness compared with healthy controls. These data suggest that TCC is associated with adverse psychological factors that may persist well after the acute episode.

     

Activation of protein kinase C inhibits TRAIL-induced caspases activation, mitochondrial events and apoptosis in a human leukemic T cell line

TRAIL causes apoptosis in numerous types of tumor cells. However, the mechanisms regulating TRAIL-induced apoptosis remain to be elucidated. We have investigated the role of PKC in regulating TRAIL-induced mitochondrial events and apoptosis in the Jurkat T cell line. We found a caspase-dependent decline in mitochondrial membrane potential and translocation of cytochrome c from mitochondria into the cytosol in response to TRAIL. Both these events were prevented by PKC activation. Moreover, PKC activation considerably reduced the activation of caspases, PARP cleavage and apoptosis when induced upon TRAIL treatment. MAPK activation was involved in the mechanism of PKC-mediated inhibition of TRAIL-induced cytochrome c release from mitochondria. Furthermore, inhibition of the MAPK pathway partially reversed the PKC-mediated inhibition of TRAIL-induced apoptosis. Besides, PKC activation may also inhibit the TRAIL-induced apoptosis through a MAPK-independent mechanism. Altogether, these results indicate a negative role of PKC in the regulation of apoptotic signals generated upon TRAIL receptor activation.     

Enhanced flux through the methylerythritol 4-phosphate pathway in Arabidopsis plants overexpressing deoxyxylulose 5-phosphate reductoisomerase

The methylerythritol 4-phosphate (MEP) pathway synthesizes the precursors for an astonishing diversity of plastid isoprenoids, including the major photosynthetic pigments chlorophylls and carotenoids. Since the identification of the first two enzymes of the pathway, deoxyxylulose 5-phoshate (DXP) synthase (DXS) and DXP reductoisomerase (DXR), they both were proposed as potential control points. Increased DXS activity has been shown to up-regulate the production of plastid isoprenoids in all systems tested, but the relative contribution of DXR to the supply of isoprenoid precursors is less clear. In this work, we have generated transgenic Arabidopsis thaliana plants with altered DXS and DXR enzyme levels, as estimated from their resistance to clomazone and fosmidomycin, respectively. The down-regulation of DXR resulted in variegation, reduced pigmentation and defects in chloroplast development, whereas DXR-overexpressing lines showed an increased accumulation of MEP- derived plastid isoprenoids such as chlorophylls, carotenoids, and taxadiene in transgenic plants engineered to produce this non-native isoprenoid. Changes in DXR levels in transgenic plants did not result in changes in␣DXS gene expression or enzyme accumulation, confirming that the observed effects on plastid isoprenoid levels in DXR-overexpressing lines were not an indirect consequence of altering DXS levels. The results indicate that the biosynthesis of MEP (the first committed intermediate of the pathway) limits the production of downstream isoprenoids in Arabidopsis chloroplasts, supporting a role for DXR in the control of the metabolic flux through the MEP pathway.     

Monitoring of marine benthic communities and taxonomic resolution: an approach through diverse habitats and substrates along the Southern Iberian coastline

Studies conducted along the southern Iberian coastline validate macrobenthic community analyses at taxonomic levels higher than that of species. Twelve studies on littoral benthic communities, carried out by the same research team, were selected spanning both a variety of sampling strategies (spatial, temporal, spatio-temporal) and substrate/habitat types (sediment, rock, algae). In order to establish differences between the results obtained at the taxonomic levels of species, family and order, similarities among stations were calculated using Spearman’s coefficient for ranges. A subset of three studies was selected to investigate possible differences in ‘best-explaining’ environmental variables with taxonomic level. The environmental variables selected at species level were the same as those found at levels of family and order. It is concluded that studies at the different levels of taxonomic resolution (species, family, order) lead to similar results both with regard to relative community distributions and the environmental variables associated with these. The importance of this result for monitoring similar benthic communities is discussed.     

High temperature effects on photosynthetic activity of two tomato cultivars with different heat susceptibility

The functional activities of the photosynthetic apparatus of two tomato cultivars of different thermotolerance were investigated after a short period of high temperature treatment. Seedlings of two tomato genotypes, Lycopersicon esculentum var. Campbell-28 and the wild thermotolerant Nagcarlang, were grown under a photoperiod of 16h at 25 degrees C and dark period of 8h at 20 degrees C. At the fourth true leaf stage, a group of plants was exposed to heat stress of 45 degrees C for 2 h. The heat shock treatment caused important reductions of the net photosynthetic rate (Pn) of Campbell-28 plants due to non-stomatal components. These non-stomatal effects were not evident in Nagcarlang-treated plants. This reduction in the CO2 assimilation rate observed in Campbell-28 was generated by affections in the Calvin cycle and also in the PSII functioning. No changes in these parameters were observed in the thermotolerant genotype after the stress. Injury to the plasma membrane because of the heat stress was evident only in the Campbell-28 genotype. Heat led to a sun-type adaptation response of the photosynthesis pigment apparatus for the Nagcarlang genotype, but not for Campbell-28, and thus an increase in chlorophyll a/b ratio and a decrease in chlorophyll/carotenoid ratio were shown in Nagcarlang stressed plants.     

Endogenous cardiac activity rhythms of continental slope Nephrops norvegicus (decapoda: nephropidae)

The endogenous cardiac activity rhythm of the Norway lobster Nephrops norvegicus was studied under constant conditions of darkness by means of a computer-aided monitoring system (CAPMON). Time series recordings of the heart rate (beats min^?1) were obtained from 47 adult males freshly collected from the continental slope (400–430?m) in the western Mediterranean. Periodogram analysis revealed the occurrence of circadian periodicity (of around 24?h) in most cases. A large percentage of animals showed significant ultradian periods (of around 12 and 18?h). The analysis of the circadian time series revealed the occurrence of peaks of heart rate activity during the expected night phase of the cycle. These results are discussed in relation to the emergence and locomotor activity rhythms of the species.     

Peroxynitrite oxidizes erythrocyte membrane band 3 protein and diminishes its anion transport capacity

We describe an altered membrane band 3 protein-mediated anion transport in erythrocytes exposed to peroxynitrite, and relate the loss of anion transport to cell damage and to band 3 oxidative modifications. We found that peroxynitrite down-regulate anion transport in a dose dependent relation (100–300 μmoles/l). Hemoglobin oxidation was found at all peroxynitrite concentrations studied. A dose-dependent band 3 protein crosslinking and tyrosine nitration were also observed. Band 3 protein modifications were concomitant with a decrease in transport activity. ( ? )-Epicatechin avoids band 3 protein nitration but barely affects its transport capacity, suggesting that both processes are unrelated. N-acetyl cysteine partially reverted the loss of band 3 transport capacity. It is concluded that peroxynitrite promotes a decrease in anion transport that is partially due to the reversible oxidation of band 3 cysteine residues. Additionally, band 3 tyrosine nitration seems not to be relevant for the loss of its anion transport capacity.