Phylogenetic analyses suggest that Psammomitra (Ciliophora,Urostylida) should represent an urostylid family,based on small subunit rRNA and alpha‐tubulin gene sequence information

The morphologically unique ciliate Psammomitra has long been considered as a systematically uncertain stichotrich. This is mainly because of its highly specialized morphology and a lack of either detailed information concerning its ontogenesis, or molecular data. Based on the small subunit rRNA (SSrRNA) gene and alpha‐tubulin gene sequences, we re‐evaluated the phylogenetic position of Psammomitra retractilis using multiple algorithms. Phylogenetic trees inferred from the SSrRNA gene sequences representing a total of 53 spirotrichs demonstrated the closest relationship of Psammomitra was with Holosticha‐like taxa, with strong support, which clearly suggested that Psammomitra should be placed into the order Urostylida although it branched at a rather deep level, and is likely to be closely related to Holostichidae. With consideration to molecular evidence and morphological characters, Psammomitra should be a clearly outlined taxon at about the rank of family, i.e. Psammomitridae stat. nov. , within the order Urostylida. The improved diagnosis for this family is as follows: Urostylida possessing extremely contractile, elongated body which consists of three parts: head, trunk, and slender tail; midventral complex composed of midventral pairs only and restricted to about anterior 1/3 of ventral surface; frontal, frontoterminal, and transverse cirri present; one left and one right marginal rows which commence near proximal end of adoral zone and extend to near rear body end.     

Molecular characterization of a fungal gene paralogue of the penicillin penDE gene of Penicillium chrysogenum

Background  

Penicillium chrysogenum converts isopenicillin N (IPN) into hydrophobic penicillins by means of the peroxisomal IPN acyltransferase (IAT), which is encoded by the penDE gene. In silico analysis of the P. chrysogenum genome revealed the presence of a gene, Pc13g09140, initially described as paralogue of the IAT-encoding penDE gene. We have termed this gene ial because it encodes a protein with high similarity to IAT (IAL for IAT-Like). We have conducted an investigation to characterize the ial gene and to determine the role of the IAL protein in the penicillin biosynthetic pathway.     

Impact of the Crystallinity on the Physical Properties of Inulin during Water Sorption

The impact of the crystallinity of spray-dried inulins on their stability and physical properties was investigated after a conditioning of 1 week at different relative humidity levels (0% to 94%) at 20 °C. An environmental scanning electron microscopy study showed that the amorphous powders hardened at a relative humidity storage between 59% and 75%; while their semi-crystalline counterparts were partially agglomerated but friable in the same conditions. Caking was observed when the glass transition temperature of the amorphous phase of the material dropped below the storage temperature of the powder. It resulted in a crystallization of the structural units of varying lengths composing inulin, but also an increase of the crystallinity of the semi-crystalline ones. This study showed the importance of the crystallinity of inulin on its stability and physical properties during storage which is of crucial importance for the shelf-life of food and pharmaceutical products in the dry state. Financial support was provided for this study by the Walloon Region of Belgium (DGTRE) and Cosucra Groupe Warcoing SA.     

Complete-genome phylogenetic approach to varicella-zoster virus evolution: genetic divergence and evidence for recombination

Recent studies of varicella-zoster virus (VZV) DNA sequence variation, involving large numbers of globally distributed clinical isolates, suggest that this virus has diverged into at least three distinct genotypes designated European (E), Japanese (J), and mosaic (M). In the present study, we determined and analyzed the complete genomic sequences of two M VZV strains and compared them to the sequences of three E strains and two J strains retrieved from GenBank (including the Oka vaccine preparation, V-Oka). Except for a few polymorphic tandem repeat regions, the whole genome, representing approximately 125,000 nucleotides, is highly conserved, presenting a genetic similarity between the E and J genotypes of approximately 99.85%. These analyses revealed that VZV strains distinctly segregate into at least four genotypes (E, J, M1, and M2) in phylogenetic trees supported by high bootstrap values. Separate analyses of informative sites revealed that the tree topology was dependent on the region of the VZV genome used to determine the phylogeny; collectively, these results indicate the observed strain variation is likely to have resulted, at least in part, from interstrain recombination. Recombination analyses suggest that strains belonging to the M1 and M2 genotypes are mosaic recombinant strains that originated from ancestral isolates belonging to the E and J genotypes through recombination on multiple occasions. Furthermore, evidence of more recent recombination events between M1 and M2 strains is present in six segments of the VZV genome. As such, interstrain recombination in dually infected cells seems to figure prominently in the evolutionary history of VZV, a feature it has in common with other herpesviruses. In addition, we report here six novel genomic targets located in open reading frames 51 to 58 suitable for genotyping of clinical VZV isolates.     

Effect of hydrocarbon concentration of pasture production (<i>Brachiaria humidicola</i>) in Texistepec,Veracruz

In this study, the relationship between the concentration of extra-heavy crude petroleum in a clayey material and the toxicity, field capacity, temperature, and growth of a tropical forage grass (Brachiara humidicola) was determined empirically. For this type of petroleum the acute toxicity (Microtox^®) was slight (CE₅₀ = 63200 - 76400 mg/kg) even at high hydrocarbon concentrations (29279 mg/kg). Nonetheless, serious impacts were encountered in terms of an increase in soil temperature (+ 1.3 °C), reduction in field capacity (-10.7%) and reduction in aerial biomass (-97%). The relationship between hydrocarbon concentration and biomass resulted in a typical dose-response curve (r = 0.99), where a concentration of 2626 mg/kg of hydrocarbons corresponds to a maintenance of 90% biomass. Furthermore, during the duration of this study (one year) the biodegradation was proportional to the pasture biomass production (r = 0.997) indicating a synergistic relationship between the petroleum biodegrading microorganisms in the rhizosphere and the pasture.     

Genetic Improvement of Willow for Bioenergy and Biofuels

Willows (Salix spp.) are a very diverse group of catkin-bearing trees and shrubs that are widely distributed across temperate regions of the globe.Some species respond well to being grown in short rotation coppice (SRC) cycles,which are much shorter than conventional forestry.Coppicing reinvigorates growth and the biomass rapidly accumulated can be used as a source of renewable carbon for bioenergy and biofuels.As SRC willows re-distribute nutrients during the perennial cycle they require only minimal nitro...     

A Tracer Bolus Method for Investigating Glutamine Kinetics in Humans

Glutamine transport between tissues is important for the outcome of critically ill patients. Investigation of glutamine kinetics is, therefore, necessary to understand glutamine metabolism in these patients in order to improve future intervention studies. Endogenous glutamine production can be measured by continuous infusion of a glutamine tracer, which necessitates a minimum measurement time period. In order to reduce this problem, we used and validated a tracer bolus injection method. Furthermore, this method was used to measure the glutamine production in healthy volunteers in the post-absorptive state, with extra alanine and with glutamine supplementation and parenteral nutrition. Healthy volunteers received a bolus injection of [1-¹³C] glutamine, and blood was collected from the radial artery to measure tracer enrichment over 90 minutes. Endogenous rate of appearance (endoR_a) of glutamine was calculated from the enrichment decay curve and corrected for the extra glutamine supplementation. The glutamine endoR_a of healthy volunteers was 6.1±0.9 µmol/kg/min in the post-absorptive state, 6.9±1.0 µmol/kg/min with extra alanyl-glutamine (p = 0.29 versus control), 6.1±0.4 µmol/kg/min with extra alanine only (p = 0.32 versus control), and 7.5±0.9 µmol/kg/min with extra alanyl-glutamine and parenteral nutrition (p = 0.049 versus control). In conclusion, a tracer bolus injection method to measure glutamine endoR_a showed good reproducibility and small variation at baseline as well as during parenteral nutrition. Additionally, we showed that parenteral nutrition including alanyl-glutamine increased glutamine endoR_a in healthy volunteers, which was not attributable to the alanine part of the dipeptide.     

Diatom Cell Size,Coloniality and Motility: Trade-Offs between Temperature,Salinity and Nutrient Supply with Climate Change

Reduction in body size has been proposed as a universal response of organisms, both to warming and to decreased salinity. However, it is still controversial if size reduction is caused by temperature or salinity on their own, or if other factors interfere as well. We used natural benthic diatom communities to explore how “body size” (cells and colonies) and motility change along temperature (2–26°C) and salinity (0.5–7.8) gradients in the brackish Baltic Sea. Fourth-corner analysis confirmed that small cell and colony sizes were associated with high temperature in summer. Average community cell volume decreased linearly with 2.2% per °C. However, cells were larger with artificial warming when nutrient concentrations were high in the cold season. Average community cell volume increased by 5.2% per °C of artificial warming from 0 to 8.5°C and simultaneously there was a selection for motility, which probably helped to optimize growth rates by trade-offs between nutrient supply and irradiation. Along the Baltic Sea salinity gradient cell size decreased with decreasing salinity, apparently mediated by nutrient stoichiometry. Altogether, our results suggest that climate change in this century may polarize seasonality by creating two new niches, with elevated temperature at high nutrient concentrations in the cold season (increasing cell size) and elevated temperature at low nutrient concentrations in the warm season (decreasing cell size). Higher temperature in summer and lower salinity by increased land-runoff are expected to decrease the average cell size of primary producers, which is likely to affect the transfer of energy to higher trophic levels.     

Gender Matters: The Relationship between Social Anxiety and Alcohol-Related Consequences

Background and Objectives

Identification of risk factors for alcohol-related consequences is an important public health concern. Both gender and social anxiety have been associated with alcohol-related consequences broadly, but it is unknown whether these variables are differentially related to specific types of alcohol-related consequences for American college students.

Methods

In the present study, 573 undergraduate students (M _age = 19.86 years, SD = 1.40; range 18 to 25; 68.9% female) completed an on-line assessment of social anxiety, alcohol use, and four types of alcohol-related consequences (personal, social, physical, and role). Poisson regressions were run to examine social anxiety, gender, and the interaction between social anxiety and gender as predictors of each type of alcohol-related consequences.

Results

After controlling for alcohol use, social anxiety was positively associated with all four types of consequences, and females endorsed higher rates of physical, personal, and role consequences. The interaction between social anxiety and gender was statistically significant only for physical consequences, with social anxiety having a stronger effect for males.

Discussion and Conclusions

These findings, which diverge somewhat from those of a prior study with Australian college students, are discussed in the context of a biopsychosocial model of social anxiety and substance use problems.

Scientific Significance

This study highlights the importance of further investigating cultural differences in the relationships among social anxiety, gender, and alcohol-related consequences.     

Effects of temperature and light on the composition of brackish-water rock pool ecosystems

I examined the effect of temperature and light on ecosystem composition was examined in a two factorial design using microcosms set up from natural rockpool communities. Furthermore I tested if the effect of temperature on different ecosystem components was dependent on the initial community composition by using communities from seven different rockpools that differed considerably in standing stocks of phytoplankton, zooplankton, zooplankton species composition, sediment mass and nutrient concentrations. Increased light caused phytoplankton biomass to decrease while zooplankton biomass and sediment dry weight was positively correlated to increased light levels. The effect of temperature on phytoplankon was largely determined by community type. Zooplankton biomass decreased with increasing temperature between 10°C and 25°C and this trend was not significantly different between different community types. A negative effect on zooplankton biomass was found at 7°C in one community. I propose, that the stronger temperature sensitivity of metabolical cost for herbivorous organisms compared to algae productivity might explain the decrease in zooplankton biomass at high temperatures. I discuss how edibility of algae and grazer characteristics may influence the response of ecosystem composition to temperature.