Analysis of the distribution of endemic and rare arthropods in high endemism areas of Algarve-South Portugal

The study of several arthropod groups in high endemism areas (HEA) of Algarve, the Southernmost province of Portugal, has revealed endemic species and species not yet recorded for the Portuguese fauna. The list includes 3 species of Isopoda endemic to Algarve, to Portugal or to the Iberian Peninsula, 2 species new to Portugal and 2 species new to the Iberian Peninsula; 2 species of Pseudoscorpiones not yet cited to Portugal; 11 species of Pauropoda new to Portugal, including one new species probably endemic; 15 species of Collembola endemic to the Portuguese or to the Iberian Peninsula faunas (Gama et al. 1997) and 37 species and 5 subspecies of Staphylinidae endemic to Algarve.With the exception of Collembola, which have been studied by us, the remaining groups have been submitted for study to several specialists.These findings heighten the biological richness of these areas of high endemism in terms of conservation of biological diversity. The authors draw attention to the necessity to preserve or restore the biological value of these areas, encouraging the adoption of protective measures and the creation of research programmes that include the implementation of taxonomic studies and co-operation between taxonomists and ecologists in order to preserve the biodiversity of these areas.     

Forest transpiration—targeted through xylem sap flux assessment versus hydrological modeling

The assessment of forest transpiration rates is crucial for determining plant-available soil water consumption and drought risk of trees. Xylem sap flux measurements have been used increasingly to quantify stand transpiration in forest ecosystems. Here, we compare this empirical approach with hydrological modeling on the basis of a stand transpiration dataset of adult beech (Fagus sylvatica), which was acquired across Bavaria, Germany, at eight forest sites. Xylem sap flux sensors were installed in five dominant trees each. Two tree to stand upscaling approaches, related to site-specific (1) sapwood area or (2) to leaf area index, were compared. The outcome was examined each in relation to process-based stand hydrological modeling, using LWF-BROOK90. Distinct relationships between tree diameter at breast height (1.30 m) and sapwood area-weighted sap flux along the radial profile became apparent across the study sites, confirming a generic allometric basis for stand-level upscaling of transpiration. The two upscaling approaches did not differ in outcome, representatively covering stand structure for comparison with modeling. Differential analysis yielded high agreement between the empirical and modeling approaches throughout most of the study period, although LWF-BROOK90 tended to overestimate sap flux measurements under low soil moisture. The two empirical approaches proved reliable for even-aged beech stands, as performance under high stand-structural heterogeneity awaits clarification. Findings advance stand-level hydrological modeling regarding coverage of stomatal behavior during temporary limitation in water availability.     

Role of the kinase MST2 in suppression of apoptosis by the proto-oncogene product Raf-1

The ablation of the protein kinase Raf-1 renders cells hypersensitive to apoptosis despite normal regulation of extracellular signal-regulated kinases, which suggests that apoptosis protection is mediated by a distinct pathway. We used proteomic analysis of Raf-1 signaling complexes to show that Raf-1 counteracts apoptosis by suppressing the activation of mammalian sterile 20-like kinase (MST2). Raf-1 prevents dimerization and phosphorylation of the activation loop of MST2 independently of its protein kinase activity. Depletion of MST2 from Raf-1-/- mouse or human cells abrogated sensitivity to apoptosis, whereas overexpression of MST2 induced apoptosis. Conversely, depletion of Raf-1 from Raf-1+/+ mouse or human cells led to MST2 activation and apoptosis. The concomitant depletion of both Raf-1 and MST2 prevented apoptosis.     

Kinetic properties of lipoxygenase from desert truffle (Terfezia claveryi Chatin) ascocarps: effect of inhibitors and activators

There is very little information available on the kinetic characteristics of fungal lipoxygenases (LOXs) because most data on the mechanism of this enzyme concern soybean LOX. In this paper, the kinetic properties of LOX from Terfezia claveryi Chatin ascocarps were studied for the first time. The enzyme did not show the "substrate aggregation-dependent activity" described for other LOXs and presented a K(m) for linoleic acid of 41 microM at pH 7.0. The effect of different inhibitors was also studied. The enzyme presented the characteristic lag phase of other LOXs, and the influence of different factors on its duration was analyzed. The lag period was reduced not only by the product of the reaction (13-HPOD) but also by 9-HPOD. Calculation of the activation constant is proposed for the first time as a useful tool for the characterization of LOX because this method makes it possible to quantify the effectiveness of different hydroperoxides as LOX activators. The activation constants obtained were 0.3 and 6.4 microM for 13- and 9-HPOD, respectively; thus, the product of the reaction was approximately 21-fold more effective than 9-HPOD as a T. claveryi LOX activator.     

Immunochemical screening and liquid chromatographic-tandem mass spectrometric confirmation of drug residues in edible tissues of calves injected with a therapeutic dose of the synthetic glucocorticoids dexamethasone and flumethasone

A field study was performed to assess the drug residue level in edible tissues after a therapeutic application of the synthetic glucocorticoids dexamethasone and flumethasone. Three diseased calves were injected intramuscularly with a commercial batch of dexamethasone esters and slaughtered 72 h after treatment. Another three calves were injected intramuscularly with an aqueous flumethasone preparation and slaughtered 24 h later. Residues of synthetic glucocorticoids in liver, muscle, kidney, and urine were assessed by competitive enzyme immunoassay. All dexamethasone concentrations exceeded the maximal residue level of 0.75 microg/kg in muscle and kidney and 2 microg/kg in the liver. The presence of both dexamethasone and flumethasone in the liver was confirmed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). These results indicate that liver tissue provides a suitable matrix to monitor the presence of illegal residues of synthetic glucocorticoids in slaughtered animals.     

Phytocomplexes from liquorice (Glycyrrhiza glabra L.) leaves--chemical characterization and evaluation of their antioxidant, anti-genotoxic and anti-inflammatory activity

Three extracts of different polarities of Glycyrrhiza glabra L. leaves were characterized and evaluated for their antioxidant, anti-genotoxic and anti-inflammatory activity. In total, thirty components have been identified and quantified through the use of liquid chromatography (LC) with ultraviolet-visible diode-array-detector (UV-vis-DAD) and mass spectrometry (MS). The main components belong to the polyphenols family, being flavonoid and dihydrostilbene derivatives. The extracts have been investigated for their antioxidant, anti-genotoxic and anti-inflammatory activities, which are fundamental requirements of efficacious chemo-preventive agents. The ethyl acetate extract proved to be the most valuable, evidently for the conspicuous presence of several polyphenols, namely flavonoids and dihydrostilbenes.     

Establishing grazing and grazing-excluded patches increases plant and invertebrate diversity in a Mediterranean oak woodland

Grazing is a global, dominant land use affecting biodiversity and ecosystem processes. In Mediterranean ecosystems grazing is a major ecological and evolutionary driver but, surprisingly, there is little information on the use of grazing as a tool to manage biodiversity in these ecosystems. We conducted an experiment to assess if establishing grazing and small scale grazing-excluded areas would increase plant and invertebrate diversity in a Mediterranean evergreen oak woodland. Plant community traits were different between treatments. Biomass of herbs (176.7 ± 18.3 g m⁻²vs 100.4 ± 10.6 g m⁻²) and litter (291.0 ± 38.3 g m⁻²vs 186.8 ± 26.4 g m⁻²), as well as the total cover of legumes (0.83 ± 0.05 vs 0.91 ± 0.03) were higher, and the proportion of bare ground (0.83 ± 0.05 vs 0.91 ± 0.03) was lower, in ungrazed plots. There were no differences in the number of plant species between treatments. Some plant species and invertebrate taxa were recorded exclusively in grazed or ungrazed plots. Invertebrate detritivores and sap sucking insects were more abundant in ungrazed plots. Ant assemblages were functionally different between treatments: Honeydew-gatherer ants were associated with ungrazed and higher plant biomass plots, and seed-eaters as well as aggressive predator ant species were associated with grazed, open habitat, plots. Management practices that maintain grazing and small scale grazing-excluded areas can increase habitat heterogeneity and promote herbaceous plant and invertebrate diversity at the local level.     

Spatial coupling of mTOR and autophagy augments secretory phenotypes

Protein synthesis and autophagic degradation are regulated in an opposite manner by mammalian target of rapamycin (mTOR), whereas under certain conditions it would be beneficial if they occurred in unison to handle rapid protein turnover. We observed a distinct cellular compartment at the trans side of the Golgi apparatus, the TOR-autophagy spatial coupling compartment (TASCC), where (auto)lysosomes and mTOR accumulated during Ras-induced senescence. mTOR recruitment to the TASCC was amino acid- and Rag guanosine triphosphatase-dependent, and disruption of mTOR localization to the TASCC suppressed interleukin-6/8 synthesis. TASCC formation was observed during macrophage differentiation and in glomerular podocytes; both displayed increased protein secretion. The spatial coupling of cells' catabolic and anabolic machinery could augment their respective functions and facilitate the mass synthesis of secretory proteins.