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We hypothesised that (i) a summer heat wave would increase the thermal stability of lakes and (ii) the size and trophic state differences would modify the lakes’ responses to heating. Within 2 years, 2008 and 2009, we studied the thermal and optical regimes of two adjacent stratified lakes in northern Italy, the oligo-mesotrophic Lake Monate (2.5 km2, max. depth 34 m) and the eutrophic Lake Varese (14.8 km2, 26 m). After the cold winter 2008–2009, a heat wave starting in May turned the whole year 2009 the second hottest after 2003. The particular sequence of meteorological events resulted in extreme vertical temperature gradients and unusually high thermal stability of both lakes. All calculated thermal parameters showed the highest values in 2009 while also the values for 2008 exceeded considerably those published for these lakes in the past. Due to the large wind exposed surface, wind mixing was supposedly the dominating mechanism of heat transfer in the shallower eutrophic Lake Varese where, due to low water transparency, large amount of solar energy trapped in the upper layers markedly increased the thermal stability. In the deeper and more transparent Lake Monate, the deeper penetrating solar irradiance contributed to better energy dissipation within the water column and smaller interannual differences in thermal stability.

We hypothesised that increasing winter affluence and summer temperatures, anticipated in southern Europe with climate change, will deteriorate the ecological status of lakes, especially in those with shorter retention time. We tested these hypotheses analysing weekly phytoplankton and chemistry data collected over 2 years of contrasting weather from two adjacent stratified lakes in North Italy, differing from each other by trophic state and water retention time. Dissolved oxygen concentrations were higher in colder hypolimnia of both lakes in the second year following the cold winter, despite the second summer was warmer and the lakes more strongly stratified. Higher loading during the rainy winter and spring increased nutrient (N, P, Si) concentrations, and a phytoplankton based trophic state index, whilst the N/P ratio decreased in both lakes. The weakened Si limitation in the second year enabled an increase of diatom biovolumes in spring in both lakes. Chlorophyll a concentration increased in the oligo-mesotrophic lake, but dropped markedly in the eutrophic lake where the series of commonly occurring cyanobacteria blooms was interrupted. The projected increase of winter precipitation in southern Europe is likely to increase the nutrient loadings to lakes and contribute to their eutrophication. The impact is proportional to the runoff/in-lake concentration ratio of nutrients rather than to the retention time, and is more pronounced in lakes with lower trophy.

A novel type of DNA-binding domain, the ‘T-box’ domain, characterizes an increasingly large family of transcription factors (Trends Genet. 15 (1999) 154). We have identified and characterized the expression pattern of a new member of the Tbr1 subfamily of T-box genes; this gene has been recently named T-bet/Tbx21 (Genomics 70 (2000) 41; Cell 17 (2000) 655; Science 292 (2001) 1907; Science 295 (2002) 338). The sequence and expression of Tbr1 and eomesodermin/Tbr2 are closely related to T-bet/Tbx21. The expression of Tbr1 (Neuron 15 (1995) 63) and Tbr2 (Mech Dev 84 (1999) 133) have virtually identical onset, at around E10.5, and expression domains in the mouse telencephalon. While Tbr1 is expressed in postmitotic neurons, Tbr2 (which is also expressed during gastrulation is also expressed in neural progenitors. We have used in situ hybridization to determine the temporal and spatial distribution of T-bet/Tbx21 expression during mouse development. T-bet/Tbx21 expression is exclusively restricted to the olfactory bulb and the thymus. To assess the distribution of T-BET/TBX21 expression in the haematopoietic compartment we used reverse transcriptase-polymerase chain reaction and found its expression in several human blood cell lineages, including progenitors/stem cells, immature B cells and peripheral T cells.

Fractalkine is a neuronally expressed chemokine that acts through its G-protein-coupled receptor CX3CR1, localized on microglial and immune cells. Fractalkine might be involved in neuroinflammatory processes secondary to neuronal damage, which normally occur in a time frame of days after ischaemia. We evaluated by in situ hybridization and immunohistochemistry the expression of fractalkine and CX3CR1 in the rat brain, after a transient occlusion of the middle cerebral artery. We found that at 12 h after ischaemia neuronal fractalkine expression was transiently increased in scattered necrotic neurons of the cortex and lost from the ischaemic striatum. At 24 and 48 h after ischaemia, fractalkine immunoreactivity was strongly increased in morphologically intact cortical neurons of the ischaemic penumbra where also the stress-inducible HSP-72 was strongly up-regulated. The intensity of fractalkine immunoreactivity of neurons in the penumbra returned to basal levels at 7 days after ischaemia. Fractalkine synthesis was also induced in endothelial cells of the infarcted area, at 48 h and 7 days after ischaemia. CX3CR1 expression was detected in the activated microglial cells of the ischaemic tissue 24 and 48 h after ischaemia, and became strongly up-regulated in macrophages/phagocytic microglia inside the infarcted tissue 7 days after ischaemia. These data suggest that fractalkine may participate in the activation and chemoattraction of microglia into the infarcted tissue, and contribute to the control of leucocyte trafficking from blood vessels into the injured area.

Item does not contain fulltext Mutations in the human Crumbs homologue 1 (CRB1) gene cause severe retinal dystrophies. CRB1 is homologous to Drosophila Crumbs, a protein essential for establishing and maintaining epithelial polarity. We have isolated the mouse orthologue, Crb1, and analyzed its expression pattern in embryonic and post-natal stages. Crb1 is expressed exclusively in the eye, and the central nervous system. In the developing eye, expression of Crb1 is detected in the retinal progenitors, and later on becomes restricted to the differentiated photoreceptor cells where it remains active up to the adult stage. In the developing neural tube, expression of Crb1 is restricted to its most ventral structures, coinciding with the expression domain of Nkx2.2. In the adult brain, Crb1 expression is defined to areas where the production and migration of neurons occurs in adulthood.

Oral-facial-digital type 1 syndrome (OFD1 [MIM 311200]) is transmitted as an X-linked dominant condition with lethality in males and is characterized by malformations of the face, oral cavity, and digits, and by a highly variable expressivity even within the same family. Malformation of the brain and polycystic kidneys are commonly associated with this disorder. The locus for OFD1 was mapped by linkage analysis to a 12-Mb interval, flanked by markers DXS85 and DXS7105 in the Xp22 region. To identify the gene responsible for this syndrome, we analyzed several transcripts mapping to the region and found mutations in OFD1 (formerly named "Cxorf5/71-7a"), encoding a protein containing coiled-coil alpha-helical domains. Seven patients with OFD1, including three with familial and four with sporadic cases, were analyzed. Analysis of the familial cases revealed a missense mutation, a 19-bp deletion, and a single base-pair deletion leading to a frameshift. In the sporadic cases, we found a missense (de novo), a nonsense, a splice, and a frameshift mutation. RNA in situ studies on mouse embryo tissue sections show that Ofd1 is developmentally regulated and is expressed in all tissues affected in OFD1 syndrome. The involvement of OFD1 in oral-facial-digital type I syndrome demonstrates an important role of this gene in human development.

In the year 2010, effluents from 90 European wastewater treatment plants (WWTPs) were analyzed for 156 polar organic chemical contaminants. The analyses were complemented by effect-based monitoring approaches aiming at estrogenicity and dioxin-like toxicity analyzed by in vitro reporter gene bioassays, and yeast and diatom culture acute toxicity optical bioassays. Analyses of organic substances were performed by solid-phase extraction (SPE) or liquid-liquid extraction (LLE) followed by liquid chromatography tandem mass spectrometry (LC-MS-MS) or gas chromatography high-resolution mass spectrometry (GC-HRMS). Target microcontaminants were pharmaceuticals and personal care products (PPCPs), veterinary (antibiotic) drugs, perfluoroalkyl substances (PFASs), organophosphate ester flame retardants, pesticides (and some metabolites), industrial chemicals such as benzotriazoles (corrosion inhibitors), iodinated x-ray contrast agents, and gadolinium magnetic resonance imaging agents; in addition biological endpoints were measured. The obtained results show the presence of 125 substances (80% of the target compounds) in European wastewater effluents, in concentrations ranging from low nanograms to milligrams per liter. These results allow for an estimation to be made of a European median level for the chemicals investigated in WWTP effluents. The most relevant compounds in the effluent waters with the highest median concentration levels were the artificial sweeteners acesulfame and sucralose, benzotriazoles (corrosion inhibitors), several organophosphate ester flame retardants and plasticizers (e.g. tris(2-chloroisopropyl)phosphate; TCPP), pharmaceutical compounds such as carbamazepine, tramadol, telmisartan, venlafaxine, irbesartan, fluconazole, oxazepam, fexofenadine, diclofenac, citalopram, codeine, bisoprolol, eprosartan, the antibiotics trimethoprim, ciprofloxacine, sulfamethoxazole, and clindamycine, the insect repellent N,N'-diethyltoluamide (DEET), the pesticides MCPA and mecoprop, perfluoroalkyl substances (such as PFOS and PFOA), caffeine, and gadolinium.

The Mediterranean and Black Seas are unique marine environments subject to important anthropogenic pressures due to atmospheric and riverine inputs of organic pollutants. They include regions of different physical and trophic characteristics, which allow the studying of the controls on pollutant occurrence and fate under different conditions in terms of particles, plankton biomass, interactions with the atmosphere, biodegradation, and their dependence on the pollutant physical chemical properties. Polycyclic Aromatic Hydrocarbons (PAHs) have been measured in samples of seawater (dissolved and particulate phases) and plankton during two east-west sampling cruises in June 2006 and May 2007. The concentrations of dissolved PAHs were higher in the south-western Black Sea and Eastern Mediterranean than in the Western Mediterranean, reflecting different pollutant loads, trophic conditions and cycling. Particle and plankton phase PAH concentrations were higher when lower concentrations of suspended particles and biomass occurred, with apparent differences due to the PAH physical chemical properties. The surface PAH particle phase concentrations decreased when the total suspended particles (TSP) increased for the higher molecular weight (MW) compounds, consistent with controls due to particle settling depletion of water column compounds and dilution. Conversely, PAH concentrations in plankton decreased at higher biomass only for the low MW PAHs, suggesting that biodegradative processes in the water column are a major driver of their occurrence in the photic zone. The results presented here are the most extensive data set available for the Mediterranean Sea and provide clear evidence of the important physical and biological controls on PAH occurrence and cycling in oceanic regions., This work was funded by the European Union and Spanish Ministry of Science and Innovation through the Thresholds projects. N. Berrojalbiz acknowledges a predoctoral fellowship from the Basque Government. C Duarte is acknowledged as PI of Thresholds project and for leading two legs of Thresholds cruises. A. Tovar and M. Alvarez are acknowledged for leading the other two Thresholds legs, respectively.

[1] The Mediterranean and Black Seas are unique marine environments subject to important anthropogenic pressures due to atmospheric and riverine inputs of organic pollutants. They include regions of different physical and trophic characteristics, which allow the studying of the controls on pollutant occurrence and fate under different conditions in terms of particles, plankton biomass, interactions with the atmosphere, biodegradation, and their dependence on the pollutant physical chemical properties. Polycyclic Aromatic Hydrocarbons (PAHs) have been measured in samples of seawater (dissolved and particulate phases) and plankton during two east-west sampling cruises in June 2006 and May 2007. The concentrations of dissolved PAHs were higher in the south-western Black Sea and Eastern Mediterranean than in the Western Mediterranean, reflecting different pollutant loads, trophic conditions and cycling. Particle and plankton phase PAH concentrations were higher when lower concentrations of suspended particles and biomass occurred, with apparent differences due to the PAH physical chemical properties. The surface PAH particle phase concentrations decreased when the total suspended particles (TSP) increased for the higher molecular weight (MW) compounds, consistent with controls due to particle settling depletion of water column compounds and dilution. Conversely, PAH concentrations in plankton decreased at higher biomass only for the low MW PAHs, suggesting that biodegradative processes in the water column are a major driver of their occurrence in the photic zone. The results presented here are the most extensive data set available for the Mediterranean Sea and provide clear evidence of the important physical and biological controls on PAH occurrence and cycling in oceanic regions.

Macroinvertebrates are one of the key components of lake ecosystems and are required to be monitored alongside other biological groups to define ecological status according to European Union legislation. Macroinvertebrate communities are highly variable and complex and respond to a diverse series of environmental conditions. The purpose of this study was to examine the relative importance of environmental variables in explaining macroinvertebrate abundance. A total of 45 sub-alpine lakes were sampled for macroinvertebrates in the shallow sublittoral. Environmental variables were grouped into four types: (1) aquatic physical and chemical parameters, (2) littoral and riparian habitat, (3) lake morphometric parameters and (4) sediment chemical characteristics. Nonparametric multiplicative regression (NPMR) was used to model the abundance of individual macroinvertebrate taxa. Significant models were produced for nine out of the 24 taxa examined. Sediment characteristics were the group most frequently included in models and also the factors to which taxa abundance was the most sensitive. Aquatic physical and chemical variables were the next group most frequently included in models although chlorophyll a was not included in any of the models and total phosphorus in only one. This indicates that many taxa may not show a direct easily interpretable response to eutrophication pressure. Lake morphometric factors were included in several of the models although the sensitivity of macroinvertebrate abundance tended to be lower than for sediment and aquatic physical and chemical factors. Habitat factors were only included in three models although riparian vegetation was found to have a significant influence on the abundance of Ephemera danica indicating that ecotone integrity is likely to play a role in its ecology. Overall, the models tended to be specific for species with limited commonality across taxa. Models produced by NPMR indicate that the response of macroinvertebrates to environmental variables can be successfully described but further research is required focussing in more detail on the response of key taxa to relevant environmental parameters and anthropogenic pressures.

Fractalkine is a neuronally expressed chemokine that acts through its G-protein-coupled receptor CX3CR1, localized on microglial and immune cells. Fractalkine might be involved in neuroinflammatory processes secondary to neuronal damage, which normally occur in a time frame of days after ischaemia. We evaluated by in situ hybridization and immunohistochemistry the expression of fractalkine and CX3CR1 in the rat brain, after a transient occlusion of the middle cerebral artery. We found that at 12 h after ischaemia neuronal fractalkine expression was transiently increased in scattered necrotic neurons of the cortex and lost from the ischaemic striatum. At 24 and 48 h after ischaemia, fractalkine immunoreactivity was strongly increased in morphologically intact cortical neurons of the ischaemic penumbra where also the stress-inducible HSP-72 was strongly up-regulated. The intensity of fractalkine immunoreactivity of neurons in the penumbra returned to basal levels at 7 days after ischaemia. Fractalkine synthesis was also induced in endothelial cells of the infarcted area, at 48 h and 7 days after ischaemia. CX3CR1 expression was detected in the activated microglial cells of the ischaemic tissue 24 and 48 h after ischaemia, and became strongly up-regulated in macrophages/phagocytic microglia inside the infarcted tissue 7 days after ischaemia. These data suggest that fractalkine may participate in the activation and chemoattraction of microglia into the infarcted tissue, and contribute to the control of leucocyte trafficking from blood vessels into the injured area.

A new, mechanistically based, in vitro strategy involving Balb/c 3T3 clone A31-1-1 mouse embryo fibroblasts has been proposed for the determination of the carcinogenic potential of inorganic chemicals, in order to establish priority of metal compounds to be tested and, whenever possible, to compare the in vitro results with the corresponding in vivo data. As a first step in this research, this study reports on the cytotoxic effects of 58 metal compounds in the Balb/3T3 cell line. After harmonisation and standardisation of the Balb/3T3 protocol, cells were exposed for 72 hours to a fixed dose (100μM) of 58 individual compounds. The cytotoxicity induced by some metal compounds was found to be related to their chemical form (for example, Cr(NO3)3 and Na2CrO4), suggesting that the Balb/3T3 cell line is a valuable cellular model in relation to this aspect of metal speciation. The results of the systematic study on the metal-induced cytotoxic effects in the Balb/3T3 cell line could be arbitrarily classified into three groups according to the degree of cytotoxicity. Group I includes 26 species that induced no observable effect or only a slight cytotoxic effect; Group II includes 13 metal compounds that exhibited an obvious degree of cytotoxicity; and Group III includes 19 metal species that displayed a strong cytotoxic response. Metal compounds of Groups II and III are considered to be of the highest priority for setting of dose–effect relationships for a subsequent in vitro study on metal-induced concurrent cytotoxicity and morphological transformation in the Balb/3T3 cell line.

We report the identification and characterization of a homologue of the IL1RAPL transcript which is responsible for a form of X-linked mental retardation (MRX34). This new transcript was cloned by analysis of genomic sequences from the Xq22 region and was named IL1RAPL2 (Interleukin 1 Receptor Accessory Protein-Like-2). The two X-linked genes share the same domains, the same exon-intron organization and a high degree of similarity at the protein level (70.4% similarity). RNA in situ expression studies on mouse embryo tissue section at different developmental stages show that Il1rapl2 is specifically expressed in the nervous system from embryonic day 12.5. The homologies together with the pattern of expression render ILRAPL2 a candidate gene for disorders displaying involvement of the CNS, including the MRX loci for which the gene has not been identified yet.