Assessment of climate change effects on mountain ecosystems through a cross-site analysis in the Alps and Apennines.

Mountain ecosystems are sensitive and reliable indicators of climate change. Long-term studies may be extremely useful in assessing the responses of high-elevation ecosystems to climate change and other anthropogenic drivers from a broad ecological perspective. Mountain research sites within the LTER (Long-Term Ecological Research) network are representative of various types of ecosystems and span a wide bioclimatic and elevational range. Here, we present a synthesis and a review of the main results from ecological studies in mountain ecosystems at 20 LTER sites in Italy, Switzerland and Austria covering in most cases more than two decades of observations. We analyzed a set of key climate parameters, such as temperature and snow cover duration, in relation to vascular plant species composition, plant traits, abundance patterns, pedoclimate, nutrient dynamics in soils and water, phenology and composition of freshwater biota. The overall results highlight the rapid response of mountain ecosystems to climate change, with site-specific characteristics and rates. As temperatures increased, vegetation cover in alpine and subalpine summits increased as well. Years with limited snow cover duration caused an increase in soil temperature and microbial biomass during the growing season. Effects on freshwater ecosystems were also observed, in terms of increases in solutes, decreases in nitrates and changes in plankton phenology and benthos communities. This work highlights the importance of comparing and integrating long-term ecological data collected in different ecosystems for a more comprehensive overview of the ecological effects of climate change. Nevertheless, there is a need for (i) adopting co-located monitoring site networks to improve our ability to obtain sound results from cross-site analysis, (ii) carrying out further studies, in particular short-term analyses with fine spatial and temporal resolutions to improve our understanding of responses to extreme events, and (iii) increasing comparability and standardizing protocols across networks to distinguish local patterns from global patterns.

Cadmium hyperaccumulation and reproductive traits in natural Thlaspi caerulescens populations.

During the last decade, the metal hyperaccumulating plants have attracted considerable attention because of their potential use in decontamination of heavy metal contaminated soils. However, in most species, little is known regarding the function, the ecological and the evolutionary significances of hyperaccumulation. In our study, we investigated the parameters influencing the Cd concentration in plants as well as the biological implications of Cd hyperaccumulation in nine natural populations of Thlaspi caerulescens. First, we showed that Cd concentration in the plant was positively correlated with plant Zn, Fe, and Cu concentrations. This suggested that the physiological and/or molecular mechanisms for uptake, transport and/or accumulation of these four heavy metals interact with each other. Second, we specified a measure of Cd hyperaccumulation capacity by populations and showed that T. caerulescens plants originating from populations with high Cd hyperaccumulation capacity had better growth, by developing more and bigger leaves, taller stems, and produced more fruits and heavier seeds. These results suggest a tolerance/disposal role of Cd hyperaccumulation in this species.

Genetic polymorphism of serum alpha-1-protease inhibitor (alpha-1-antitrypsin): Pi i, a deficient allele of the Pi system.

The microheterogeneity of the I allele of the Pi system of APi (alpha-1-antitrypsin) was studied in 43 individuals with the new PAGIF technique. The unique aspect of the I allele product (unequal distribution of bands 4 and 6), previously demonstrated with acid-starch gel, was confirmed. In addition, two subtypes of the Pi I allele--I1 and I2--were clearly distinguished. Serum concentrations of APi associated with the expression of the I allele were significantly decreased (68% of normal values) and thus very similar to those associated with the expression of the S allele. This indicates that the I allele can be considered as a "deficient" allele of the Pi system.

Alpha-1-antitrypsin phenotypes in Lyon, France.

Alpha-1-antitrypsin Pi phenotyping was performed by thin-layer isoelectric focusing on samples from 1653 healthy white blood donors. The variants were confirmed by the acid-starch gel technique and crossed immunoelectrophoresis, with complete agreement between the two methods. The allele frequencies in this population were PiM, 0.9019; PiS, 0.0713;PiZ,0.0142; PiI, 0.0036; PiF, 0.0036; PiV, 0.0024. In addition, some rare phenotypes (MX, IS, LM) were noted. No difference was noted in the distribution of the variant alleles between males and females. The significance of the high frequency of the S allele is related to the ethnic origin of this population. The agreement of the results obtained by our technique and by acid-starch gel electrophoresis confirms the validity of Pi determination by thin-layer isoelectric focusing.

Alpha-I-antitrypsin (Pi) phenotypes in Lyon, France: departure from Hardy-Weinberg equilibrium.

The validity of the Hardy-Weinberg equilibrium for Pi phenotypes was tested in a population of 1,653 randomly selected, healthy blood donors in Lyon, France. A significant departure from the equilibrium was found, with an excess of FF and SS homozygotes and a deficiency of FM heterozygotes.

[Alpha-1-antitrypsin deficiency. Phenotype study of 60 members of the same family]. / Déficit en alpha-1-antitrypsine. Etude du phénotype de 60 membres d'une même famille

In two brothers treated for severe pulmonary emphysema, was demonstrated an alpha-1-antitrypsin deficiency associated with a ZZ phenotype (Pi system). The authors carried out a genetic study of the family including 60 members spread over 4 generations. In all, were demonstrated 4 subjects of phenotype ZZ, 29 of phenotype MZ, 3 of phenotype MS ; one subject had a phenotype SZ and 23 members of this family had normal levels of alpha-1-antitrypsin and were of phenotype MM. The disease was transmitted in all cases as an autosomic codominant. The interest of a study of the phenotype in alpha-1-antitrypsin deficiency is emphasized together with the practical steps to be taken on discovery of a subject with the allele responsible for a reduction in serum levels of alpha-1-antitrypsin.

[Methods of sampling and preservation of blood used during extracorporeal circulation]. / Modalités de prélèvement et de conservation du sang utilisé au cours des circulations extra-corporelles

The blood supply of Cardiac Surgery Centers set quantitative and qualitative problems to the Centers of blood dispatch. In this work, from a Lyonese experience on 4,000 E.C.C., authors try to define the best preservative solution, especially for the respiratory function of the red blood cell. The C.P.D. solution (citrate, phosphate, dextrose) answers to requirements in this field when the blood used is less than 48 hours old. In the meantime, it is not impossible that studies based on definite criteriums of evaluation and on severe comparisons allows to adapt new process from which some are described and criticized in this work.