Interstitial 2q24.3 deletion including SCN2A and SCN3A genes in a patient with autistic features,psychomotor delay,microcephaly and no history of seizures

Mutations in neuronal voltage-gated sodium channel genes SCN1A, SCN2A, and SCN3A may play an important role in the etiology of neurological diseases and psychiatric disorders, besides various types of epilepsy. Here we describe a 3-year-old boy with autistic features, language delay, microcephaly and no history of seizures. Array-CGH analysis revealed an interstitial deletion of ~ 291.9 kB at band 2q24.3 disrupting the entire SCN2A gene and part of SCN3A. We discuss the effects of haploinsufficiency of SCN2A and SCN3A on the genetic basis of neurodevelopmental and neurobehavioral disorders and we propose that this haploinsufficiency may be associated not only with epilepsy, but also with autistic features.     

Efficacy of different antifouling treatments for seawater cooling systems

In an industrial seawater cooling system, the effects of three different antifouling treatments, viz. sodium hypochlorite (NaClO), aliphatic amines (Mexel®432) and UV radiation, on the characteristics of the fouling formed were evaluated. For this study a portable pilot plant, as a side-stream monitoring system and seawater cooling system, was employed. The pilot plant simulated a power plant steam condenser, having four titanium tubes under different treatment patterns, where fouling progression could be monitored. The nature of the fouling obtained was chiefly inorganic, showing a clear dependence on the antifouling treatment employed. After 72 days the tubes under treatment showed a reduction in the heat transfer resistance (R) of around 70% for NaClO, 48% for aliphatic amines and 55% for UV, with respect to the untreated tube. The use of a logistic model was very useful for predicting the fouling progression and the maximum asymptotic value of the increment in the heat transfer resistance (ΔR _max). The apparent thermal conductivity (λ) of the fouling layer showed a direct relationship with the percentage of organic matter in the collected fouling. The characteristics and mode of action of the different treatments used led to fouling with diverse physicochemical properties.     

Genome wide sequence analysis grants unbiased definition of species boundaries in “Candidatus Phytoplasma”

The phytoplasmas are currently named using the Candidatus category, as the inability to grow them in vitro prevented (i) the performance of tests, such as DNA-DNA hybridization, that are regarded as necessary to establish species boundaries, and (ii) the deposition of type strains in culture collections. The recent accession to complete or nearly complete genome sequence information disclosed the opportunity to apply to the uncultivable phytoplasmas the same taxonomic approaches used for other bacteria. In this work, the genomes of 14 strains, belonging to the 16SrI, 16SrIII, 16SrV and 16SrX groups, including the species “Ca. P. asteris”, “Ca. P. mali”, “Ca. P. pyri”, “Ca. P. pruni”, and “Ca. P. australiense” were analyzed along with Acholeplasma laidlawi, to determine their taxonomic relatedness. Average nucleotide index (ANIm), tetranucleotide signature frequency correlation index (Tetra), and multilocus sequence analysis of 107 shared genes using both phylogenetic inference of concatenated (DNA and amino acid) sequences and consensus networks, were carried out. The results were in large agreement with the previously established 16S rDNA based classification schemes. Moreover, the taxonomic relationships within the 16SrI, 16SrIII and 16SrX groups, that represent clusters of strains whose relatedness could not be determined by 16SrDNA analysis, could be comparatively evaluated with non-subjective criteria. “Ca. P. mali” and “Ca. P. pyri” were found to meet the genome characteristics for the retention into two different, yet strictly related species; representatives of subgroups 16SrI-A and 16SrI-B were also found to meet the standards used in other bacteria to distinguish separate species; the genomes of the strains belonging to 16SrIII were found more closely related, suggesting that their subdivision into Candidatus species should be approached with caution.     

Joint distribution of first exit times of a two dimensional Wiener process with jumps with application to a pair of coupled neurons

Motivated by a neuronal modeling problem, a bivariate Wiener process with two independent components is considered. Each component evolves independently until one of them reaches a threshold value. If the first component crosses the threshold value, it is reset while the dynamics of the other component remains unchanged. But, if this happens to the second component, the first one has a jump of constant amplitude; the second component is then reset to its starting value and its evolution restarts. Both processes evolve once again until one of them reaches again its boundary. In this work, the coupling of the first exit times of the two connected processes is studied.     

The impact of climate on the geographical distribution of phytoplankton species in boreal lakes

Here, we use a novel space-by-time approach to study large-scale changes in phytoplankton species distribution in Swedish boreal lakes in response to climate variability. Using phytoplankton samples from 27 lakes, evenly distributed across Sweden, all relatively unimpacted by anthropogenic disturbance and sampled annually between 1996 and 2010, we found significant shifts in the geographical distribution of 18 species. We also found significant changes in the prevalence of 45 species (33 became more common and 12 less common) over the study period. Using species distribution models and phytoplankton samples from 60 lakes sampled at least twice between 1992 and 2010, we evaluated the importance of climate variability and other environmental variables on species distribution. We found that temperature (e.g., extreme events and the duration of the growing season) was the most important predictor for species detections. Many cyanobacteria, chlorophytes, and, to a lesser extent, diatoms and zygnematophytes, showed congruent and positive responses to temperature. In contrast, precipitation explained little variation and was important only for a few taxa (e.g., Staurodesmus spp., Trachelomonas volvocina). At the community level, our results suggest a change in community composition at temperatures over 20 °C and growing seasons longer than 40 days. We conclude that climate is an important driver of the distributional patterns of individual phytoplankton species and may drive changes in community composition in minimally disturbed boreal lakes.     

Environmental-dependent proline accumulation in plants living on gypsum soils

Biosynthesis of proline—or other compatible solutes—is a conserved response of all organisms to different abiotic stress conditions leading to cellular dehydration. However, the biological relevance of this reaction for plant stress tolerance mechanisms remains largely unknown, since there are very few available data on proline levels in stress-tolerant plants under natural conditions. The aim of this work was to establish the relationship between proline levels and different environmental stress factors in plants living on gypsum soils. During the 2-year study (2009–2010), soil parameters and climatic data were monitored, and proline contents were determined, in six successive samplings, in ten taxa present in selected experimental plots, three in a gypsum area and one in a semiarid zone, both located in the province of Valencia, in south-east Spain. Mean proline values varied significantly between species; however, seasonal variations within species were in many cases even wider, with the most extreme differences registered in Helianthemum syriacum (almost 30 μmol g^?1 of DW in summer 2009, as compared to ca. 0.5 in spring, in one of the plots of the gypsum zone). Higher proline contents in plants were generally observed under lower soil humidity conditions, especially in the 2009 summer sampling preceded by a severe drought period. Our results clearly show a positive correlation between the degree of environmental stress and the proline level in most of the taxa included in this study, supporting a functional role of proline in stress tolerance mechanisms of plants adapted to gypsum. However, the main trigger of proline biosynthesis in this type of habitat, as in arid or semiarid zones, is water deficit, while the component of ‘salt stress’ due to the presence of gypsum in the soil only plays a secondary role.     

Diphenyl Diselenide Reduces Mechanical and Thermal Nociceptive Behavioral Responses After Unilateral Intrastriatal Administration of 6-Hydroxydopamine in Rats

Parkinson’s disease (PD) patients, in addition to motor dysfunction, also present alterations in pain sensation. The present study characterized the antinociceptive effects of diphenyl diselenide ((PhSe)₂) in a model of nociception induced by unilateral, intrastriatal 6-hydroxydopamine (6-OHDA) injection in rats. Male adult Wistar rats received 20 μg/3 μl of 6-OHDA (in saline solution containing 0.02 % of ascorbic acid) or 3 μl of vehicle into the right striatum (1.0 mm anterior, 3.0 mm lateral, and 5.0 mm ventral—with respect to the bregma). Thirty days after injection, rats received (PhSe)₂ intragastrically at a dose of 10 mg/kg 1 h before behavioral tests (von Frey hairs, hot plate, tail immersion, formalin, and open field). Our results demonstrated that 6-OHDA injection to rats augmented the response frequency of von Frey hairs (VHF) stimulation, besides reducing the thermal withdrawal latency in the hot plate test. Importantly, the (PhSe)₂ treatment decreased the mechanical allodynia measured by the response frequency of VHF stimulation and diminished the thermal nociception in the hot plate test in 6-OHDA-injected rats. In conclusion, these results revealed that a single oral administration of (PhSe)₂ 1 h prior to the accomplishment of the behavioral tests was effective to attenuate the increased mechanical and thermal nociception caused by a single intrastriatal 6-OHDA injection to rats. Furthermore, other clarifying studies are warranted to improve the evidence bases for future clinical use of (PhSe)₂ as a new alternative therapy for the treatment of painful symptoms associated to PD.