Sodium demand of microorganisms in the phyllosphere and the organic layer of a tropical montane forest in south Ecuador

Recent studies raise the hypothesis that Na shortage restricts decomposition and affects the carbon cycle in tropical forests. When Na concentrations in soils are low and the stands are far off-coast, they do not receive substantial Na inputs from the atmosphere. Since terrestrial plants have low concentrations of Na, which is not considered as an essential element, the demand of soil fauna may not be covered. Yet, in contrast to animals, little is known of Na demands of fungi and phyllosphere microorganisms. We present results from a study on Na limitation in a montane forest ecosystem in South Ecuador, which is located on the eastern cordillera of the Andes. We tested the hypotheses that (1) the study area is characterized by low Na concentrations because of low deposition rates with incident precipitation (wind directions mainly from the Amazonian Basin), (2) decomposition processes are limited by fauna and fungal Na restrictions and (3) Na is retained in the canopy because of Na limitation of microorganisms in phyllosphere. Since 1998, we measure Na fluxes in rainfall, throughfall, stemflow, litter leachate, litterfall and organic layer in a microcatchment under an undisturbed lower montane rainforest. Results reveal comparatively low Na concentrations in the ecosystem and similar Na concentrations in throughfall and stemflow. Since Na fluxes are lower with throughfall than with incident rainfall, we conclude that Na is retained in the canopy. To explore the role of the phyllosphere in Na retention we sampled leaves covered by phyllosphere microorganisms and leaves without phyllosphere cover from several tree species, which were sprayed with a NaCl solution containing 0.5 mg L-1 Na, corresponding to the Na concentration in incident rainfall in our study area. Additionally, responses of litter decomposition to Na additions and the involved interaction of soil fungi and fauna were tested in a litterbag experiment at two sites (1000 and 2000 m a.s.l.). Results revealed enhanced decomposition rates following Na additions, though only in the presence of soil fauna. These results might have future ecosystem implications, since our time series showed that total Na deposition decreased within the past 15 years from ca. 40 kg ha-1 a-1 to 10 kg ha-1 a-1, suggesting a potential role of Na in regulating ecosystem processes

Base metal budgets of a small catchment in a tropical montane forest in South Ecuador

In a tropical montane rain forest in south Ecuador, the alkali and earth alkali metals Ca, Mg, K, and Na are supplied by weathering of the parent substrate consisting of phyllites and metasandstones and by atmospheric inputs. Phases of acid deposition are interrupted by alkalinization through episodic basic dust deposition. Although the biological productivity of most terrestrial ecosystems is thought to be N- and/or P-limited, there is increasing evidence that the essential plant nutrients K, Na, Mg and Ca can also limit biological functioning. We quantified biological and geochemical contributions to base metal fluxes and set up a metal budget of a ca. 9.1-ha large catchment from 1998 to 2013. The catchment is characterized by a high annual interception loss (28–50 %) and a low contribution of stem flow to throughfall. Mean total annual soil input (throughfall + stemflow + litterfall) was 13800 ± 1500 mg m-2 (Ca, mean ± SD), 19000 ± 1510 (K), 4690 ± 619 (Mg) and 846 ± 592 (Na) of which 22 ± 6 % (Ca), 45 ± 16 (K), 39 ± 10 (Mg) and 84 ± 33 (Na) were leached to soil horizons below the organic layer. The three nutrient metals Ca, K and Mg were thus to a large part retained in the biotic part of the catchment. The canopy budget of K was consistently and most pronouncedly negative. The canopy budgets of Ca and Mg were closely correlated and in most years negative, while the budget of Na was consistently positive, indicating net retention of this element in the canopy. The mineral soil retained 79–94 % of Ca, K and Mg, while Na was net released from the mineral soil. The size of mainly biologically controlled aboveground fluxes of Ca, K and Mg was 1-2 orders of magnitude larger than that of mainly geochemically controlled fluxes which are driven by sorption to soil and weathering. Annual net hydrological fluxes (bulk deposition – stream flow) were –66 ± 278 mg m-2 (Ca), 361 ± 421 (K), –188 ± 159 (Mg) and –1700 ± 587 (Na). If estimated dry deposition was included, the system accumulated 86 kg Ca ha-1 and 199 kg K ha-1, had a nearly balanced budget of Mg (+0.3 kg ha-1) and lost 56 kg of Na ha-1 in the last 15 years. The strongest driver of all budgets was the input flux into the various compartments

Expression of bcl-2 and p53 in bovine cutaneous fibropapillomas

BACKGROUND: Bovine cutaneous fibropapillomas are benign hyperproliferative lesions induced by Bovine Papillomaviruses (BPVs). Bcl-2 is an important anti-apoptotic protein which is expressed in several cancer types. In contrary, p53 is a tumour suppressor protein that mediates cell cycle arrest, apoptosis and senescence in response to cellular stresses. FINDINGS: Here, we investigated immunohistochemically and biochemically, the expression of bcl-2 and p53 in a subset of BPV positive fibropapillomas and bovine normal skin. Normal skin samples showed a weak signal for both proteins in the cytoplasm of the basal cells. Nine out of twelve (75%) tumour samples stained positive for bcl-2 throughout basal and parabasal layers, with most of cells showing strong cytoplasmic immunoreactivity. Nine out of twelve (75%) fibropapillomas were found to be positive for p53 expression, showing a strong cytoplasmic and perinuclear staining of p53 protein mainly in the basal and parabasal layers. CONCLUSIONS: Our data reveal an altered bcl-2 and p53 immunoreactivity in bovine cutaneous fibropapillomas, suggesting involvement of these two proteins in the cutaneous neoplastic transformation through an impaired apoptotic process. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1750-9378-10-2) contains supplementary material, which is available to authorized users

Chlorpheniramine Potentiates the Analgesic Effect in Migraine of Usual Caffeine, Acetaminophen, and Acetylsalicylic Acid Combination

Previous studies indicated that addition of the antihistaminic chlorpheniramine to the usual combination of acetylsalicylic acid, acetaminophen, and caffeine further increases their synergism both in terms of anti-inflammatory and analgesic effect. The present non-interventional study tested the superiority of two Algopirin® tablets, containing a total of 250 mg acetylsalicylic acid (ASA), 150 mg acetaminophen (paracetamol, PAR), 30 mg caffeine (CAF) and 4 mg chlorpheniramine (CLF) vs. a combination containing 250 mg ASA, 250 mg PAR, and 65 mg CAF recognized as “safe and effective” by FDA in treating migraine. Patients evaluated their pain intensity on the Visual Analog Scale—VAS(PI) before and 30, 60, 120, 180, and 240 min after drug intake. Interpretation of the pain curves as “survival pain curves” was considered as a method for direct comparison of the pain curves. This interpretation permitted the application of the log rank test for comparison of pain hazards. The results of the applied parametric and non-parametric statistical tests indicated significant differences between the main endpoints: both Areas Under Pain Curves and time to decrease of the pain intensity to less than 50% of the initial value comparisons highlighted that Algopirin® was more efficient in spite of smaller doses of PAR and CAF. Comparison of “survival of pain” led to the same conclusion concerning the superiority of Algopririn. Consequently, the addition of CLF permitted decreasing of ASA, PAR, and CAF doses as well as their potential side effects, without a loss of analgesic effect

Plant diversity enhances the natural attenuation of polycyclic aromatic compounds (PAHs and oxygenated PAHs) in grassland soils

Increasing plant species richness stimulates microbial activity in soil, which might favor biodegradation of polycyclic aromatic compounds (PACs). To explore the relationship between plant community composition and PACs in grassland soils (Fluvisols exposed to an urban atmosphere), we determined the concentrations of 29 polycyclic aromatic hydrocarbons (PAHs) and 15 oxygenated PAHs (OPAHs) in topsoils of 80 plots of a grassland biodiversity experiment. The plots included different levels of plant species richness (1, 2, 4, 8, 16, 60 species) and 1–4 plant functional groups (grasses, small herbs, tall herbs, and legumes) in a randomized block design. The concentrations (ng g−1) of ∑29PAHs and ∑15OPAHs in the soils were 271–2407 and 57–329, respectively. Concentrations of 16 (out of 44) PACs and ∑29PAHs decreased significantly with increasing plant species richness, after accounting for the effects of block and initial soil organic C concentration (ANCOVA, p 4 aromatic rings on plant species richness yielded slopes that were negatively correlated with their octanol-water partitioning coefficients, (ii) two OPAHs accumulated in soils with higher plant species richness, and (iii) higher plant species richness increased four OPAH/parent-PAH ratios. Accordingly, structural equation modeling indicated that the higher concentration of 1,2-acenaphthenequinone (a metabolite of acenaphthene) and the higher 1,2-acenaphthenequinone/acenaphthene and 1-indanone/fluorene ratios in plots with higher plant species richness were partly explained by higher soil microbial biomass on plots with higher plant species richness. We conclude that higher plant species richness can be used to enhance biodegradation of aged PACs in soil. We however caution that OPAHs (some of which are more toxic than their related PAHs) might accumulate in soils during such a plant-assisted remediation process