Increasing drought effects on five European pines modulate Δ13C-growth coupling along a Mediterranean altitudinal gradient.

Climate warming increases vulnerability to drought in Mediterranean water-limited forests. However, we still lack knowledge of the long-term physiological responses of coexisting pine species in these forests regarding their ability to cope with warming-induced drought stress. We investigated spatiotemporal patterns of tree performance for five isohydric pines with partially overlapping ecological niches in the eastern Iberian Peninsula along an altitudinal gradient: Pinus halepensis = P. pinaster ≤ P. nigra ≤ P. sylvestris ≤ P. uncinata. Using indexed tree-ring widths (TRWi) we assessed changes in temporal coherence of radial growth (growth synchrony, âC) over the period 1902-2011 across three elevation belts: low ≈ 1100 m; mid = 1615 m; high = 2020 m. We also examined by mixed modelling whether TRWi showed an increased coupling with leaf-level gas exchange (inferred from indexed carbon isotope discrimination, Δ13Ci) by enhanced stomatal regulation in response to an amplified regional drought stress. Increasingly negative annual water balances (decrease in annual precipitation minus evapotranspiration = -4.8 mm year−1; 1970-2011) prompted more synchronous growth of coexisting pines between low- and mid-elevation belts, with âC rising from 0.25 ± 0.04 (1902-1951) to 0.62 ± 0.05 (1962-2011). This effect was coupled with tighter stomatal regulation at mid-elevation as indicated by high correlations between TRWi and Δ13Ci (>0.60 from the mid-1970s onwards) which resembled those found at low-elevation. Simultaneously, TRWi vs. Δ13Ci uncoupling occurred at the high-elevation belt across species. Weaker growth-climate relationships as elevation increased highlighted the major role of the altitude-dependent thermal gradient in growth responsiveness to drought; however, an intensified Δ13Ci response to spring water availability across elevation belts observed from mid-1970s onwards suggested regional shifts in tree physiological activity linked to earlier seasonal drought impacts. Warming-induced drought stress is spreading to higher altitudes in Iberian pinewoods as multispecies growth is linked to progressively tighter stomatal control of water losses reflected in wood Δ13C

Role of mitochondria in the pheromone- and amiodarone-induced programmed death of yeast

Although programmed cell death (PCD) is extensively studied in multicellular organisms, in recent years it has been shown that a unicellular organism, yeast Saccharomyces cerevisiae, also possesses death program(s). In particular, we have found that a high doses of yeast pheromone is a natural stimulus inducing PCD. Here, we show that the death cascades triggered by pheromone and by a drug amiodarone are very similar. We focused on the role of mitochondria during the pheromone/amiodarone-induced PCD. For the first time, a functional chain of the mitochondria-related events required for a particular case of yeast PCD has been revealed: an enhancement of mitochondrial respiration and of its energy coupling, a strong increase of mitochondrial membrane potential, both events triggered by the rise of cytoplasmic [Ca2+], a burst in generation of reactive oxygen species in center o of the respiratory chain complex III, mitochondrial thread-grain transition, and cytochrome c release from mitochondria. A novel mitochondrial protein required for thread-grain transition is identified

Methodology for Development of a 600-Year Tree-Ring Multi-Element Record for Larch from the Taymir Peninsula, Russia

We developed a long (600-year) dataset for the concentrations of 26 elements in tree rings of larch from the Taymir Peninsula, the northernmost region in the world (ca. 72°N) where trees grow. Tree rings corresponding to the time period from 1300 to 1900 A.D. were studied. Eleven wood strips, each from a different larch tree, were cut into ca. 100 mg samples usually consisting of ten consecutive tree rings (but occasionally five). Between 19 and 40 consecutive samples resulted from each tree, yielding a total of 277 samples. The replication of each time interval ranged from three (for periods 1300-1400 A.D. and 1600-1700 A.D.) to six (for 1450-1600 A.D.). Wood samples were digested with concentrated HNO 3 for measurement of Li, B, Na, Mg, Al, Si, P, Cl, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, I, Ba, La, Ce, Nd, W, Au, Pb, Bi, Th, and U using solution Inductively Coupled Plasma Mass Spectrometry (ICPMS). Fourteen elements (V, Co, As, Y, Nb, Mo, Sb, La, Ce, Nd, W, Au, Th, and U) with extremely low concentrations were eliminated from consideration as unreliable. Here we report our sample preparation and measurement procedure, as well as the observed concentrations in tree rings, emphasizing considerations for developing representative and reliable denrodochemical datasets.Нами был получен длительный массив данных (600 лет) концентраций 26 элементов в годичных кольцах лиственницы с полуострова Таймыр, самого северного региона в мире (около 72° с.ш.), где возможен рост деревьев. Изучались годичные кольца, соответствующие промежутку времени с 1300 по 1900 год н.э. Одиннадцать древесных выпилов, по одному для каждой лиственницы, нарезались на образцы массой около 100 мг, которые, как правило, состояли из десяти годичных колец (но в некоторых случаях из пяти). Из каждого дерева было получено от 19 до 40 последовательных образцов, что дало в общей сложности 277 образцов. Повторность для каждого временного интервала варьировала от трех (для периодов 1300-1400 г.н.э. и 1600-1700 г.н.э.) до шести (для периода 1450-1600 г.н.э.). Древесные образцы растворяли в концентрированной HNO 3 для последующего измерения Li, B, Na, Mg, Al, Si, P, Cl, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, I, Ba, La, Ce, Nd, W, Au, Pb, Bi, Th и U при помощи масс-спектрометрии с индуктивно связанной плазмой (ICP-MS) для растворов. Четырнадцать элементов (V, Co, As, Y, Nb, Mo, Sb, La, Ce, Nd, W, Au, Th и U) с очень низкими концентрациями были исключены из рассмотрения как недостоверные. В данной статье, основной целью которой являлась отработка методики получения репрезентативных и достоверных дендрохимических данных, приводится использованная нами процедура пробоподготовки и измерений, а также полученные концентрации в годичных кольцах

Influence of the atrio-ventricular delay optimization on the intra left ventricular delay in cardiac resynchronization therapy

BACKGROUND: Cardiac Resynchronization Therapy (CRT) leads to a reduction of left-ventricular dyssynchrony and an acute and sustained hemodynamic improvement in patients with chronic heart failure. Furthermore, an optimized AV-delay leads to an improved myocardial performance in pacemaker patients. The focus of this study is to investigate the acute effect of an optimized AV-delay on parameters of dyssynchrony in CRT patients. METHOD: 11 chronic heart failure patients with CRT who were on stable medication were included in this study. The optimal AV-delay was defined according to the method of Ismer (mitral inflow and trans-oesophageal lead). Dyssynchrony was assessed echocardiographically at three different settings: AVD(OPT); AVD(OPT)-50 ms and AVD(OPT)+50 ms. Echocardiographic assessment included 2D- and M-mode echo for the assessment of volumes and hemodynamic parameters (CI, SV) and LVEF and tissue Doppler echo (strain, strain rate, Tissue Synchronisation Imaging (TSI) and myocardial velocities in the basal segments) RESULTS: The AVD(OPT )in the VDD mode (atrially triggered) was 105.5 ± 38.1 ms and the AVD(OPT )in the DDD mode (atrially paced) was 186.9 ± 52.9 ms. Intra-individually, the highest LVEF was measured at AVD(OPT). The LVEF at AVD(OPT )was significantly higher than in the AVD(OPT-50)setting (p = 0.03). However, none of the parameters of dyssynchrony changed significantly in the three settings. CONCLUSION: An optimized AV delay in CRT patients acutely leads to an improved systolic left ventricular ejection fraction without improving dyssynchrony

A novel expression cassette delivers efficient production of exclusively tetrameric human butyrylcholinesterase with improved pharmacokinetics for protection against organophosphate poisoning

© 2015 Published by Elsevier B.V. Butyrylcholinesterase is a stoichiometric bioscavenger against poisoning by organophosphorus pesticides and nerve agents. The low level of expression and extremely rapid clearance of monomeric recombinant human butyrylcholinesterase (rhBChE) from bloodstream (t1/2;≈2 min) limits its pharmaceutical application. Recently (Ilyushin at al., PNAS, 2013) we described a long-acting polysialylated recombinant butyrylcholinesterase (rhBChE-CAO), stable in the bloodstream, that protects mice against 4.2 LD50 of VR. Here we report a set of modifications of the initial rhBChE expression vector to improve stability of the enzyme in the bloodstream and increase its production in CHO cells by introducing in the expression cassette: (i) the sequence of the natural human PRAD-peptide in frame with rhBChE gene via "self-processing" viral F2A peptide under control of an hEF/HTLV promoter, and (ii) previously predicted in silico MAR 1-68 and MAR X-29 sequences. This provides fully tetrameric rhBChE (4rhBChE) at 70 mg/l, that displays improved pharmacokinetics (t1/2; = 32 ± 1.2 h, MRT = 43 ± 2 h). 3D Fluorescent visualization and distribution of 125I-labeled enzyme reveals similar low level 4rhBChE and rhBChE-CAO accumulation in muscle, fat, and brain. Administered 4rhBChE was mainly catabolized in the liver and breakdown products were excreted in kidney. Injection of 1.2 LD50 and 1.1 LD50 of paraoxon to BALB/c and knockout BChE-/- mice pre-treated with 4rhBChE (50 mg/kg) resulted in 100% and 78% survival, respectively, without perturbation of long-term behavior. In contrast, 100% mortality of non-pre-treated mice was observed. The high expression level of 4rhBChE in CHO cells permits consideration of this new expression system for manufacturing BChE as a biopharmaceutical

Global Spore Sampling Project: A global, standardized dataset of airborne fungal DNA

Novel methods for sampling and characterizing biodiversity hold great promise for re-evaluating patterns of life across the planet. The sampling of airborne spores with a cyclone sampler, and the sequencing of their DNA, have been suggested as an efficient and well-calibrated tool for surveying fungal diversity across various environments. Here we present data originating from the Global Spore Sampling Project, comprising 2,768 samples collected during two years at 47 outdoor locations across the world. Each sample represents fungal DNA extracted from 24 m3 of air. We applied a conservative bioinformatics pipeline that filtered out sequences that did not show strong evidence of representing a fungal species. The pipeline yielded 27,954 species-level operational taxonomic units (OTUs). Each OTU is accompanied by a probabilistic taxonomic classification, validated through comparison with expert evaluations. To examine the potential of the data for ecological analyses, we partitioned the variation in species distributions into spatial and seasonal components, showing a strong effect of the annual mean temperature on community composition.publishedVersio

Mechanisms of the noxious inflammatory cycle in cystic fibrosis

Multiple evidences indicate that inflammation is an event occurring prior to infection in patients with cystic fibrosis. The self-perpetuating inflammatory cycle may play a pathogenic part in this disease. The role of the NF-κB pathway in enhanced production of inflammatory mediators is well documented. The pathophysiologic mechanisms through which the intrinsic inflammatory response develops remain unclear. The unfolded mutated protein cystic fibrosis transmembrane conductance regulator (CFTRΔF508), accounting for this pathology, is retained in the endoplasmic reticulum (ER), induces a stress, and modifies calcium homeostasis. Furthermore, CFTR is implicated in the transport of glutathione, the major antioxidant element in cells. CFTR mutations can alter redox homeostasis and induce an oxidative stress. The disturbance of the redox balance may evoke NF-κB activation and, in addition, promote apoptosis. In this review, we examine the hypotheses of the integrated pathogenic processes leading to the intrinsic inflammatory response in cystic fibrosis

Airborne DNA reveals predictable spatial and seasonal dynamics of fungi.

Fungi are among the most diverse and ecologically important kingdoms in life. However, the distributional ranges of fungi remain largely unknown as do the ecological mechanisms that shape their distributions1,2. To provide an integrated view of the spatial and seasonal dynamics of fungi, we implemented a globally distributed standardized aerial sampling of fungal spores3. The vast majority of operational taxonomic units were detected within only one climatic zone, and the spatiotemporal patterns of species richness and community composition were mostly explained by annual mean air temperature. Tropical regions hosted the highest fungal diversity except for lichenized, ericoid mycorrhizal and ectomycorrhizal fungi, which reached their peak diversity in temperate regions. The sensitivity in climatic responses was associated with phylogenetic relatedness, suggesting that large-scale distributions of some fungal groups are partially constrained by their ancestral niche. There was a strong phylogenetic signal in seasonal sensitivity, suggesting that some groups of fungi have retained their ancestral trait of sporulating for only a short period. Overall, our results show that the hyperdiverse kingdom of fungi follows globally highly predictable spatial and temporal dynamics, with seasonality in both species richness and community composition increasing with latitude. Our study reports patterns resembling those described for other major groups of organisms, thus making a major contribution to the long-standing debate on whether organisms with a microbial lifestyle follow the global biodiversity paradigms known for macroorganisms4,5

Moose and snowshoe hare competition and a mechanistic explanation from foraging theory

Moose ( Alces alces ) and snowshoe hare ( Lepus americanus ) appear to compete with each other. This was determined using the “natural experiments” of populations found in sympatry and allopatry on islands at Isle Royale National Park, Michigan, and manipulated exclosures. The population densities from these areas are fit to a series of competition models based upon different competitive mechanisms (Schoener 1974a), using non-linear regression techniques. A model of competition for food where the food can be separated into exclusively used and shared categories is found to predict observed densities of moose and hare best. Finally, the competition model's parameters (fraction of food shared and competition coefficients) are shown to agree with values predicted independently from a foraging model.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47750/1/442_2004_Article_BF00396753.pd