Effects of desiccation on native and non‐native molluscs in rivers

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How allometric scaling relates to soil abiotics

For most species, the logarithm of their average body mass is negatively related to the logarithm of their relative population density, i.e. the numerical abundance. In this way, the allometric scaling (both mass–abundance regressions and body–size spectra) becomes useful in ecological theory to build and explain food webs. Using empirical evidence derived from 145 Dutch sites, a hypothesis is formulated to explain how soil microbivores, detritivores and predators react to increasing resource availability. Shifts in size distribution, and subsequently changes in soil food‐web structure, are further discussed in the perspective of Holling's sequential interactions between basic system functions. We show that the allometric scaling and the averages of the (log‐transformed) prey:predator body‐mass ratios are reliable predictors for assessing faunal responses to nutrient availability. We view this work as a first attempt toward an extensive comparison of ecological processes in different soil systems.     

The Biphasic Effects of Moderate Alcohol Consumption with a Meal on Ambiance-Induced Mood and Autonomic Nervous System Balance: A Randomized Crossover Trial

Background

The pre-drinking mood state has been indicated to be an important factor in the mood effects of alcohol. However, for moderate alcohol consumption there are no controlled studies showing this association. Also, the mood effects of consuming alcohol combined with food are largely unknown. The aim of this study was to investigate the effects of moderate alcohol combined with a meal on ambiance-induced mood states. Furthermore effects on autonomic nervous system activity were measured to explore physiological mechanisms that may be involved in changes of mood state.

Methods

In a crossover design 28 women (age 18–45 y, BMI 18.5–27 kg/m²) were randomly allocated to 4 conditions in which they received 3 glasses of sparkling white wine (30 g alcohol) or alcohol-free sparkling white wine while having dinner in a room with either a pleasant or unpleasant created ambiance. Subjects filled out questionnaires (B-BAES, POMS and postprandial wellness questionnaire) at different times. Skin conductance and heart rate variability were measured continuously.

Results

Moderate alcohol consumption increased happiness scores in the unpleasant, but not in the pleasant ambiance. Alcohol consumption increased happiness and stimulation feelings within 1 hour and increased sedative feelings and sleepiness for 2.5 hour. Skin conductance was increased after alcohol within 1 hour and was related to happiness and stimulation scores. Heart rate variability was decreased after alcohol for 2 hours and was related to mental alertness.

Conclusion

Mood inductions and autonomic nervous system parameters may be useful to evaluate mood changes by nutritional interventions. Moderate alcohol consumption elevates happiness scores in an unpleasant ambiance. However, drinking alcohol during a pleasant mood results in an equally positive mood state.

Trial Registration

Clinicaltrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01426022","term_id":"NCT01426022"}}NCT01426022.     

Interleukin 10 mitigates the development of the zymosan-induced multiple organ dysfunction syndrome in mice.

We investigated the effect of interleukin 10 on the development of zymosan-induced multiple organ dysfunction syndrome (MODS) and on plasma concentrations and production capacity of tumour necrosis factor (TNF)-alpha by peritoneal cells. Groups of C57BL/6 mice received a single intraperitoneal injection with zymosan, a cell wall component of Saccharomyces cerevisiae, at day 0. Daily doses of human recombinant interleukin 10 (IL-10: 10 or 50 microg/kg) were given intraperitoneally either starting directly before administration of zymosan (day 0), or 5 or 8 days after administration of zymosan. The animals were monitored for survival, condition, body weight and temperature. On day 12 all surviving animals were killed to obtain plasma, organs and peritoneal cells. Plasma concentrations of TNF-alpha and lipopolysaccharide-stimulated production of TNF-alpha by peritoneal cells were measured; organ weights were registered as an indicator for organ damage. IL-10 improves survival and clinical condition and also reduces organ damage, but only at the highest dose used and only when started simultaneously with the administration of zymosan. Circulating TNF-alpha concentrations 12 days after zymosan are not affected by any of the IL-10 schedules used. However, lipopolysaccharide-stimulated production of TNF-alpha by peritoneal cells is increased, in a dose- and time-dependent fashion. The anti-inflammatory cytokine IL-10 is able to attenuate the development of MODS in this model, but only when given simultaneously with zymosan, and in high dosages.     

Identification and molecular characterization of BP75, a novel bromodomain-containing protein.

We here describe the identification and characterization of a novel bromodomain-containing protein, the bromodomain protein of 75 kDa (BP75). Initially, we identified BP75 in a two-hybrid screening for proteins that interact with the first PDZ (acronym for post-synaptic density protein PSD-95, Drosophila discs large tumor suppressor DlgA and the tight junction protein ZO-1) domain in protein tyrosine phosphatase-BAS-like (PTP-BL). We found that BP75 is expressed ubiquitously and show that both BP75 and a PTP-BL deletion mutant consisting of the first PDZ domain are located mainly in the nucleus, although cytoplasmic localization is also evident. Full-length PTP-BL, on the contrary, is predominantly localized in the cytoplasm, although some basal nuclear staining is observed. The described molecular interaction may reflect a mechanism of coupling submembraneous signalling events and nuclear events.     

Distribution of lecithin-retinol acyltransferase activity in different types of rat liver cells and subcellular fractions

It is now well documented that lecithin-retinol acyltransferase (LRAT) is the physiologically important enzyme activity involved in the esterification of retinol in the liver. However, no information regarding the cellular distribution of this enzyme in the liver is presently available. This study characterizes the distribution of LRAT activity in the different types of rat liver cells. Purified preparations of isolated parenchymal, fat-storing, and Kupffer + endothelial cells were isolated from rat livers and the LRAT activity present in microsomes prepared from each of these cell fractions was determined. The fat-storing cells were found to contain the highest level of LRAT specific activity (383 +/- 54 pmol retinyl ester formed min-1.mg-1 versus 163 +/- 22 pmol retinyl ester formed min-1.mg-1 for whole liver microsomes). The level of LRAT specific activity in parenchymal cell microsomes (158 +/- 53 pmol retinyl ester formed min-1.mg-1) was very similar to LRAT levels in whole liver microsomes. The Kuppfer + endothelial cell microsome fractions were found to contain LRAT, at low levels of activity. These results indicate that the fat-storing cells are very enriched in LRAT but the parenchymal cells also posses significant levels of LRAT activity.     

Petunia peroxidase a: isolation, purification and characteristics

The fast-moving anionic peroxidase isoenzyme variant PRXa was purified from leaves of petunia (Petunia hybrida). Over 1300-fold purification was achieved by subjecting extracellular extracts to two sequential acetone precipitations and resuspending the pellets at pH 5.0 and pH 8.0, respectively, followed by gel filtration and chromatofocusing. The purified enzyme had an absorbance ratio (A405 nm/A280 nm) of 3.6, a molecular mass of about 37 kDa and a pI of 3.8. Three molecular forms with slightly different molecular masses were separated by concanavalin-A--Sepharose affinity chromatography, indicating that these three forms differ in their carbohydrate moieties. The absorption spectrum of PRXa had maxima at 496 and 636 nm and a Soret band at 405 nm. Spectra of compounds I and IV were obtained by titrating a batch of PRXa stored for several months at -20 degrees C with H2O2. The addition of 1 mol H2O2/mol freshly purified PRXa caused the formation of compound II, indicating that freshly isolated PRXa contains a bound hydrogen donor which is lost upon storage. Compound III was obtained from both preparations in the presence of excess H2O2. The pH optimum of PRXa for the reaction with H2O2 and guaiacol was 5.0 and its specific activity 61 mkat/g protein. Among various aromatic compounds, coniferyl alcohol was polymerized by PRXa to presumed lignin-like material. The extracellular localization and high affinity of PRXa for the cinnamic acid derivatives suggest that this isoenzyme functions in the polymerization or cross-linking of lignin in the plant cell wall.     

Growth media in anaerobic fermentative processes: The underestimated potential of thermophilic fermentation and anaerobic digestion

Fermentation and anaerobic digestion of organic waste and wastewater is broadly studied and applied. Despite widely available results and data for these processes, comparison of the generated results in literature is difficult. Not only due to the used variety of process conditions, but also because of the many different growth media that are used. Composition of growth media can influence biogas production (rates) and lead to process instability during anaerobic digestion. To be able to compare results of the different studies reported, and to ensure nutrient limitation is not influencing observations ascribed to process dynamics and/or reaction kinetics, a standard protocol for creating a defined growth medium for anaerobic digestion and mixed culture fermentation is proposed. This paper explains the role(s) of the different macro- and micronutrients, as well as the choices for a growth medium formulation strategy. In addition, the differences in nutrient requirements between mesophilic and thermophilic systems are discussed as well as the importance of specific trace metals regarding specific conversion routes and the possible supplementary requirement of vitamins. The paper will also give some insight into the bio-availability and toxicity of trace metals. A remarkable finding is that mesophilic and thermophilic enzymes are quite comparable at their optimum temperatures. This has consequences for the trace metal requirements of thermophiles under certain conditions. Under non-limiting conditions, the trace metal requirement of thermophilic systems is about 3 times higher than for mesophilic systems.