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Developmental stability of an individual is often evaluated by means of fluctuating asymmetry (FA) in bilaterally paired morphological characters. Even though FA has been widely investigated in ungulates, its connection with the condition of individuals and their environment is still debated. In this study we investigated factors contributing to FA in horn length in the sexually monomorphic Alpine chamois. We measured right and left horn length of 1682 Alpine chamois (Nfemales = 734; Nmales = 948) shot during 2 consecutive hunting seasons (2015 and 2016) in 7 neighbouring districts in Central-Eastern Alps (Italy). We found no consistent left or right bias. Within our study population, FA values were normally distributed around a mean value that was not significantly different from zero (Skewness = − 0.107, SE = 0.06; Kurtosis = − 0.055, SE = 0.119). We also found that absolute FA in horn length was affected by environmental and climatic conditions experienced by the individuals during their first year and half of life. Statistically significant differences between right and left horn length were found with higher local population density and lower forage quality (i.e., siliceous substrate). Moreover, snow cover duration during the individuals’ first winter increased horn length asymmetry. No individual characteristics played a role in promoting horn length asymmetry. The associations between exposure to stressors and deviations from bilateral symmetry suggest that absolute FA can be used to identify populations whose individuals experienced stressful conditions early in life. We found in this relatively monomorphic species that both male and female horns were equally affected by climate, substrate, and local population density, thus showing that large male secondary sexual characters, such as the antlers of deer stags, are not the only traits which can be influenced by a negative environment and exhibit increasing FA.

Bahiagrass (Paspalum notatum Flüggé) is one of the main components of the South American grasslands, and it is cultivated for forage and turf around the world. At present, hybridization is the most common breeding technique for the species, and its goal is to obtain superior apomictic hybrids. The objective of the present study was to determine the relationship between heterosis, reproductive behavior, and genetic distances between parents in tetraploid bahiagrass. Genetic distance between 24 sexual tetraploid genotypes and 24 apomictic tetraploid genotypes of P. notatum was evaluated using Simple Sequence Repeat (SSR) and Inter Simple Sequence Repeat (ISSR) markers. Crosses were made between parents with low, intermediate or high genetic distances. Six families were generated. A marker linked to apospory in bahiagrass was used to determine segregation for mode of reproduction, and embryo sac were characterized to estimate the level of apospory expressivity. The ratio between sexual and aposporous hybrids ranged from 1:1 to 9:1 among families. Discontinuous variation for apospory expressivity was observed among hybrids, with either low or high levels being exhibited. A significant relationship between genetic distance and proportion of aposporous hybrids was observed. Heterosis was observed for all the evaluated traits and its level was dependent on the parental combination. Genetic distances between parents was related to heterosis, mainly for forage yield, which is the most important trait in forage species. Hence, molecular markers may be useful to predict the occurrence of heterosis for this trait. Fil: Marcón, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Martínez, Eric Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Rodríguez, Gustavo Rubén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Zilli, Alex Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Brugnoli, Elsa Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Acuña, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

An evaluation of the concentration of metals in terrestrial and aquatic environments near Artigas Antarctic Scientific Base was assessed. Granulometric characteristics, total organic matter content, concentration of metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) and metalloid (As) in soil, marine and freshwater sediments were determined. The geoaccumulation index (Igeo) was used in order to analyse the contamination magnitude. Samples were collected in summer 2015–2016 covering 31 sampling stations; 15 terrestrial/soil stations (T0–T14) were placed considering the distribution of Artigas Base buildings and the septic tanks’ location. Eleven freshwater stations were placed along the three meltwater streams near Artigas Base (S0–S10), and two in Uruguay Lake (L1 and L2). Finally, three marine stations in Maxwell Bay were placed one near the Artigas Base (AB) and two far from it in North Cove (NC1, NC2). Some of the terrestrial stations (T2, T10, T11 and T13) presented the highest concentration of metals and Igeo values, which was associated to anthropic activities. Highest metal levels were related to fuel storage and handling, but also, with sewage release and the presence of old leaded paint residues. These polluted sites were limited to a restricted area of Artigas Base, not affecting surrounding environments. Concentrations of the analysed metals in unpolluted sites had the same order of magnitude recorded in other unpolluted areas of the Fildes Peninsula and other Antarctic regions.

The study investigated the anti-tumour effect of zoledronic acid (ZA) administered alone in a biological window therapy in naïve bone-only metastatic and locally advanced breast cancer (LABC) patients. 33 patients with LABC (Group 1) and 20 patients with a first diagnosis of bone metastasis only (Group 2) received 4 mg single dose of ZA, 14 days (biological window) before starting any treatment. In Group 1, Ki67, CD34, p53/bcl-2 and caspase 3 expression along with the adenosine triphosphate (ATP) levels and RNA disruption index were evaluated as markers of tumor growth in tumour specimens obtained before and after ZA administration (basal, day 14). In Group 2, the total enumeration of circulating tumour cells (CTCs), and of M30+ve CTCs along with the soluble marker of cell death (M30/M65) were carried-out as markers of tumor dissemination at baseline, at 48 h and day 14th. In Group 1, there was a significant reduction in Ki67, CD34, bcl-2 expression after 14 days ZA based-treatment (p = 0.0032; p = 0.0001, p < 0.00001 respectively). ZA showed a significant increase of RNA disruption (p < 0.0076). In Group 2, we observed a significant reduction of CTCs number after 48 h (p = 0.0012), followed by a significant rebound at 14 days (p = 0.012). The apoptotic CTCs/M30+ve and M65 levels significantly increased under treatment (p = 0.018 and p = 0.039 respectively) after drug administration when compared to the baseline. These results are the first prospective in vivo data showing the direct pure anti-tumour effect (either on the tumour cell or on CTCs) of ZA.

Climate change may turn Arctic biomes from carbon sinks into sources and vice versa, depending on the balance between gross ecosystem photosynthesis, ecosystem respiration (ER) and the resulting net ecosystem exchange (NEE). Photosynthetic capacity is species specific, and thus, it is important to quantify the contribution of different target plant species to NEE and ER. At Ny Alesund (Svalbard archipelago, Norway), we selected different Arctic tundra plant species and measured CO2 fluxes at plot scale and photosynthetic capacity at leaf scale. We aimed to analyze trends in CO2 fluxes during the transition seasons (beginning vs. end of the growing season) and assess which abiotic (soil temperature, soil moisture, PAR) and biotic (plot type, phenology, LAI, photosynthetic capacity) factors influenced CO2 emissions. NEE and ER differed between vegetation communities. All communities acted as CO2 sources, with higher source strength at the beginning than at the end of the growing season. The key factors affecting NEE were soil temperature, LAI and species-specific photosynthetic capacities, coupled with phenology. ER was always influenced by soil temperature. Measurements of photosynthetic capacity indicated different responses among species to light intensity, as well as suggesting possible gains in response to future increases in atmospheric CO2 concentrations. Species-specific adaptation to low temperatures could trigger significant feedbacks in a climate change context. Our data highlight the need to quantify the role of dominant species in the C cycle (sinks or sources), as changes of vegetation composition or species phenology in response to climate change may have great impact on the regional CO2 balance.

In the last two centuries, persecution and deforestation caused grey wolf Canis lupus populations in Europe to decline. Recently, their numbers started to recover although most populations still remain isolated from one another. This study presents the first documented evidence of the successful reconnection of the Dinaric-Balkan and the Alpine wolf populations via long-distance dispersal and subsequent reproduction. A young male wolf radiocollared in the Dinaric Mountains in July 2011 travelled through Slovenia and Austria to the Italian Alps, where he settled in March 2012. During the 98 days of dispersal period, the wolf has travelled a cumulative line distance of 1176 km crossing multiple anthropogenic and natural barriers, and successfully hunting wild prey until he settled 233 km straight line distance from its natal territory. Camera trapping, snow tracking and genetic evidence in the new territory confirmed pairing with a female wolf from the neighbouring Alpine population. In the following year, the pair has produced a first documented “mixed” litter between wolves from the Dinaric-Balkan and the Alpine wolf populations. This case study demonstrates the potential for the future merging of European wolf populations even in human-dominated landscapes and highlights the importance of transboundary cooperation in wolf research and management.

Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most common genetic cause of Parkinson's disease. Here, we investigated whether the G2019S LRRK2 mutation causes morphological and/or functional changes at nigro-striatal dopamine neurons. Density of striatal dopaminergic terminals, nigral cell counts, tyrosine hydroxylase protein levels as well as exocytotic dopamine release measured in striatal synaptosomes, or striatal extracellular dopamine levels monitored by in vivo microdialysis were similar between ≥12-month-old G2019S knock-in mice and wild-type controls. In vivo striatal dopamine release was insensitive to the LRRK2 inhibitor Nov-LRRK2-11, and was elevated by the membrane dopamine transporter blocker GBR-12783. However, G2019S knock-in mice showed a blunted neurochemical and motor activation response to GBR-12783 compared to wild-type controls. Western blot and dopamine uptake analysis revealed an increase in dopamine transporter levels and activity in the striatum of 12-month-old G2019S KI mice. This phenotype correlated with a reduction in vesicular monoamine transporter 2 levels and an enhancement of vesicular dopamine uptake, which was consistent with greater resistance to reserpine-induced hypolocomotion. These changes were not observed in 3-month-old mice. Finally, Western blot analysis revealed no genotype difference in striatal levels of endogenous α-synuclein or α-synuclein bound to DOPAL (a toxic metabolite of dopamine). However, Serine129-phosphorylated α-synuclein levels were higher in 12-month-old G2019S knock-in mice. Immunohistochemistry confirmed this finding, also showing no genotype difference in 3-month-old mice. We conclude that the G2019S mutation causes progressive dysfunctions of dopamine transporters, along with Serine129-phosphorylated α-synuclein overload, at striatal dopaminergic terminals, which are not associated with dopamine homeostasis dysregulation or neuron loss but might contribute to intrinsic dopaminergic terminal vulnerability. We propose G2019S knock-in mice as a presymptomatic Parkinson's disease model, useful to investigate the pathogenic interaction among genetics, aging, and internal or environmental factors leading to the disease.

Vav1 is a critical signal transducer for both the development and function of normal hematopoietic cells, in which it regulates the acquisition of maturation-related properties, including adhesion, motility, and phagocytosis. Vav1 is also important for the agonist-induced maturation of acute promyelocytic leukemia (APL)-derived promyelocytes, in which it promotes the acquisition of a mature phenotype by playing multiple functions at both cytoplasmic and nuclear levels. We investigated the possible role of Vav1 in the differentiation of leukemic precursors to monocytes/macrophages. Tumoral promyelocytes in which Vav1 was negatively modulated were induced to differentiate into monocytes/macrophages with phorbol-12-myristate-13-acetate (PMA) and monitored for their maturation-related properties. We found that Vav1 was crucial for the phenotypical differentiation of tumoral myeloid precursors to monocytes/macrophages, in terms of CD11b expression, adhesion capability and cell morphology. Confocal analysis revealed that Vav1 may synergize with actin in modulating nuclear morphology of PMA-treated adherent cells. Our data indicate that, in tumoral promyelocytes, Vav1 is a component of lineage-specific transduction machineries that can be recruited by various differentiating agents. Since Vav1 plays a central role in the completion of the differentiation program of leukemic promyelocytes along diverse hematopoietic lineages, it can be considered a common target for developing new therapeutic strategies for the various subtypes of myeloid leukemias.

We investigated phytoplankton biomass, assemblage structure and production along an environmental gradient to evaluate if chlorophyll-a (as proxy for biomass) and primary production peaked under conditions hypothesised to favour phytoplankton growth. During Spring 2003, a wide area from shallow estuarine waters to the shelf slope off the Rio de la Plata was sampled and routine measurements included CTD profiles, nutrients, chlorophyll-a, phytoplankton composition and abundance, seston and organic matter loads, downwelling light and, at selected stations, production versus irradiance experiments. Spatial differences in abiotic variables suggested distinct hydrographic zones that differed in phytoplankton biomass and productivity. Chlorophyll-a was highest under estuarine influence and peaked at low salinity when strong stratification developed in the outer estuary, and was minimum at the shelf break and slope. In that area, however, relatively high chlorophyll-a was associated to oceanographic fronts and to the occurrence of Sub Antarctic water within the photic depth range. Productivity was maximum in shallow waters, but biomass-specific productivity peaked at the outer shelf in oceanographic fronts or in upwelled Sub Antarctic waters. Over shelf and slope waters productivity and biomass were not tightly coupled, as indicated by situations of high biomass and low productivity (Station 9), low biomass and high productivity (Station 10), or both high biomass and productivity (Station 22). Ordination analysis of phytoplankton taxa suggested that assemblages changed gradually along the environmental gradient and correlated to abiotic variables defining geographic zones. Overall results were consistent with an interpretation that phytoplankton biomass and growth were modulated by light in estuarine and coastal waters, and by hydrographic processes on the continental shelf and slope.

The pharmacological inhibitors of phosphoinositide 3-kinase (PI3K)/Akt pathway have been proposed in the treatment of leukemia based on their antiproliferative effects. However, several studies demonstrated the activation of PI3K in the nuclei of all-trans-retinoic acid (ATRA) - differentiated HL-60 cells, raising the possibility that PI3K/Akt-inhibitors may block antitumor properties of retinoids. The aim of the present study was to investigate the possible activation of nuclear Akt in ATRA-treated cells and to test the effects of Akt-inhibitors on ATRA-mediated differentiation. The Akt-activity was found to be increased in the nuclei and lysates of ATRA-differentiated HL-60 and NB4 cells. The down-modulation of the expression of Akt protein in HL-60 cells using siRNA reduces the CD11b expression in ATRA-treated cells. The treatment of both cell lines with the commercially available Akt inhibitors inhibited the growth of both control and ATRA-treated cells. Akt-inhibitors had no inhibitory effects on ATRA-mediated growth arrest and the expression of CD11b in HL-60 cells, but increased the percentage of control cells expressing CD11b. In contrast, the presence of Akt inhibitors reduced the expression of CD11b in ATRA-treated NB4 cells.

Plant metabolic activity in arid and semi-arid environments is largely tied to episodic precipitation events or "pulses". The ability of plants to take up and utilize rain pulses during the growing season in these water-limited ecosystems is determined in part by pulse timing, intensity and amount, and by hydrological properties of the soil that translate precipitation into plant-available soil moisture. We assessed the sensitivity of an invasive woody plant, velvet mesquite (Prosopis velutina Woot.), to large (35 mm) and small (10 mm) isotopically labeled irrigation pulses on two contrasting soil textures (sandy-loam vs. loamy-clay) in semi-desert grassland in southeastern Arizona, USA. Predawn leaf water potential (psi(pd)), the isotopic abundance of deuterium in stem water (deltaD), the abundance of 13C in soluble leaf sugar (delta13C), and percent volumetric soil water content (theta(v)) were measured prior to irrigation and repeatedly for 2 weeks following irrigation. Plant water potential and the percent of pulse water present in the stem xylem indicated that although mesquite trees on both coarse- and fine-textured soils quickly responded to the large irrigation pulse, the magnitude and duration of this response substantially differed between soil textures. After reaching a maximum 4 days after the irrigation, the fraction of pulse water in stem xylem decreased more rapidly on the loamy-clay soil than the sandy-loam soil. Similarly, on both soil textures mesquite significantly responded to the 10-mm pulse. However, the magnitude of this response was substantially greater for mesquite on the sandy-loam soil compared to loamy-clay soil. The relationship between psi(pd) and delta13C of leaf-soluble carbohydrates over the pulse period did not differ between plants at the two sites, indicating that differences in photosynthetic response of mesquite trees to the moisture pulses was a function of soil water availability within the rooting zone rather than differences in plant biochemical or physiological constraints. Patterns of resource acquisition by mesquite during the dynamic wetting-drying cycle following rainfall pulses is controlled by a complex interaction between pulse size and soil hydraulic properties. A better understanding of how this interaction affects plant water availability and photosynthetic response is needed to predict how grassland structure and function will respond to climate change.

The relationships between photosynthetic efficiency, non-radiative energy dissipation and carotenoid composition were studied in leaves ofLigustrum ovalifolium developed either under full sunlight or in the shade. Sun leaves contained a much greater pool of xanthophyll cycle components than shade leaves. The rate of non-radiative energy dissipation, measured as non-photochemical fluorescence quenching (NPQ), was strictly related to the deepoxidation state (DPS) of xanthophyll cycle components in both sun and shade leaves, indicating that zeaxanthin (Z) and antheraxanthin (A) are involved in the development of NPQ. Under extreme conditions of excessive energy, sun leaves showed higher maximum DPS than shade leaves. Therefore, sun leaves contained not only a greater pool of xanthophyll cycle components but also a higher proportion of violaxanthin (V) actually photoconvertible to A and Z, compared to shade leaves. Both these effects contributed to the higher NPQ in sun versus shade leaves. The amount of photoconvertible V was strongly related to chla/b ratio and inversely to leaf neoxanthin content. This evidence indicates that the amount of photoconvertible V may be dependent on the degree of thylakoid membrane appression and on the organization of chlorophyll-protein complexes, and possible explanations are discussed. Exposure to chilling temperatures caused a strong decline in the photon yield of photosynthesis and in the intrinsic efficiency of PS II photochemistry in sun leaves, but little effects in shade leaves. These effects were accompanied by increases in the pool of xanthophyll cycle components and in DPS, more pronounced in sun than in shade leaves. This corroborates the view that Z and A may play a photoprotective role under unfavorable conditions. In addition to the xanthophyll-related non-radiative energy dissipation, a slow relaxing component of NPQ, independent from A and Z concentrations, has been found in leaves exposed to low temperature and high light. This quenching component may be attributed either to other regulatory mechanism of PS II efficiency or to photoinactivation.

Changes in photochemical efficiency, non-radiative energy dissipation (NRD), de-epoxidation state of xanthophyll cycle components (DPS) and contents of the antioxidants ascorbic acid and glutathione were studied in leaves of the poikilohydric Ramonda serbica Panc. (Gesneriaceae) during cycles of dehydration and subsequent rehydration. In drying leaves, the intrinsic efficiency of PS II photochemistry and the photon yield of PS II electron transport showed strong progressive decreases. Simultaneously, the fraction of excitation energy dissipated as heat in the PS II antenna increased markedly. The energy-dependent component of non-photochemical quenching (NPQ) showed an increase in dehydrating leaves down to relative water contents (RWC) values near 30%. Further decreases in RWC below these values caused a decrease in NPQ. Accordingly, DPS showed a similar behaviour, with a sharp increase and a subsequent decrease at very low RWC, although the maximum DPS was reached at slightly lower RWC than that for the maximum NPQ. The pools of reduced ascorbate and glutathione increased strongly when the RWC values fell below 40% and remained high in fully dehydrated leaves. When plants were re-watered photosynthetic efficiency, NRD, DPS and antioxidant contents recovered their initial control values. However, during rehydration, the zeaxanthin content showed a transient increase, as did NPQ, indicating an increasing demand for non-radiative dissipation. On the other hand, the contents of reduced ascorbate and reduced glutathione decreased but were still relatively high in the initial phase of rehydration, when the rate of photosynthetic electron transport, proton pumping and NRD were still relatively low. These results indicate that several photoprotective mechanisms are operating in R. serbica. Protection from photo-oxidation and photoinhibition appears to be achieved by co-ordinated contributions by ascorbate, glutathione and zeaxanthin-mediated NPQ. This variety of photoprotective mechanisms may be essential for conferring desiccation-tolerance.