GABA, 5-HT and amino acids in the rotifers Brachionus plicatilis and Brachionus rotundiformis

gamma-Aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT) have been shown to increase the reproduction of the Brachionus plicatilis (NH3L strain). In the present study, the endogenous presence of GABA and 5-HT in the rotifers B. plicatilis (NH3L and Kamiura strains) and Brachionus rotundiformis (Langkawi strain) were confirmed by dot blot immunoassay and high-performance liquid chromatography (HPLC). HPLC showed that GABA and 5-HT concentrations in the three rotifer strains range from 71 to 188 pmol/mg and from 12 to 64 pmol/mg, respectively. A total of 33 amino acids were also detected in B. plicatilis and B. rotundiformis, with glutamic acid, serine, glycine, taurine, threonine, alanine, arginine, proline, valine and isoleucine in high concentrations relative to other amino acids.     

The expression and activity of monoamine oxidase A, but not of the serotonin transporter, is decreased in human placenta from pre-eclamptic pregnancies

Serotonin (5-HT) plays a pivotal role in pregnancy and a hyperserotonomic condition has been documented in pre-eclampsia. We have attempted to elucidate the possible participation of 5-HT as an aetiological factor in pre-eclampsia, by estimating the activity and expression of the 5-HT transporter (SERT) and monoamine oxidase A (MAO-A) in human placenta from full term normal (NG) and severe pre-eclamptic (PES) pregnancies. Uptake of 5-[1,2-3H] hydroxytryptamine binoxalate (specific radioactivity, 30.4 Ci/mmol) was determined in placental brush border vesicles by a rapid filtration technique. 5-HT metabolism in placental homogenate was measured using a HPLC-ECD system. Expression of SERT and MAO-A was determined by Western blot, using specific antibodies against the human SERT and MAO-A in placental tissues obtained from NG and PES. Our results, showed no significant difference in 5-HT uptake between both groups. However, 5-HT metabolism was significantly lower in placental homogenates from PES than in NG placentas, with the pathological preparations showing no MAO-A activity against 5-HT during the first 60 min of incubation (87% and 5% of metabolism of 5-HT initially added, NG and PES respectively). Western blot analysis showed a similar expression of SERT in BBMV from NG and PES. However, unlike for normal pregnancies, the expression of MAO-A in placental homogenates from PES was found to be very low, or almost negligible. These findings confirm our previous results and suggest that the higher plasma free 5-HT levels observed in severe pre-eclampsia could be mainly due to a reduction in placental MAO-A expression and activity and are not limited by the expression and uptake of 5-HT into the placental tissue.     

Gene flow and allozymic population structure in the clam Venus antiqua (King of Broderip), (Bivalvia, Veneriidae) from Southern Chile

Using horizontal electrophoresis, 13 allozyme loci were screened in 144 adult clams (Venus antiqua) (King of Broderip) from 5 geographic samples in southern Chile. Polymorphism was detected at 11 loci across the sampling localities. Gene frequency differences rather than the alternative fixation of alleles characterize these collecting sites. Direct-count heterozygosity fluctuated between 6.8% and 10.3%, with a generalized and significant heterozygote deficiency detected in every locality. Similar levels of genetic diversity were detected in both exploited banks and one presumed unmanaged population. Substantial estimates of demic structuration were found at the total population (F_ST=0.107) and regional levels (F_ST=0.143), with coinciding high inbreeding estimates (F_IS=0.57). Although no statistically significant evidence of genetic substructuring was found at the within-region comparison (F_ST=0.007), a generalized heterozygote deficiency (F_IS=0.57) also characterized that hierarchical level. Spatial correlation of gene frequencies indicated a nearly random distribution of genotypes along the latitudinal distribution of samples. The high rates of global, and the within-region rates of gene flow suggest substantial larval interchange via long-distance dispersal that prevent differentiation by drift alone. Accordingly, no discrete genetic units can be recognized for the species at any spatial scale. Apparently, high recruitment rates help in replenishing genetic variants lost by continuous overfishing, thus explaining why human extraction has not resulted in major losses of genetic variation for individual populations. The slow-growing rate and delayed sexual maturation of this clam species are apparently stronger limiting factors than human-induced genetic erosion for the conservation of natural beds and viable captive management of V. antiqua.     

Filamentous fungi preservation in distilled water.

Some methods for keeping the fungal Culture Collection have been used. However, the choice of either one on the basis that must ensure the cultural genetic stability and its phenotipic characteristics. In this work the preservation method in distilled water recognized in the literature as a single, economic and certain method that guarantie the survival of fungus cultures for long periods was used. 26 strains of generus and species: Aspergillus niger, Aspergillus candidus, Fusarium sp., Fusarium moniliforme, Mucor griseocyanum, Syncephalastrum sp., Trichoderma sp., Trichoderma harzianum and Trichoderma koningii were preserved. Enough inoculum from well developed cultures (mainly spores and hyphae) poured in flasks with sterile distilled water warranted a 100% of survival of those microorganisms for two years. At the same time no apparent changes were observed in respect to morphology and macroscopic features.     

Polymorphism of the pig acetyl-coenzyme A carboxylase α gene is associated with fatty acid composition in a Duroc commercial line

Acetyl-coenzyme A carboxylase α (ACACA) catalyses the first committed step in the biosynthesis of long-chain fatty acids (FA) by converting acetyl-CoA into malonyl-CoA. In pigs, the ACACA gene maps to a chromosome 12 QTL with important effects on FA composition. In the present study, we have sequenced the coding region of the pig ACACA gene in 15 pigs, identifying 21 polymorphic sites that were either synonymous or non-coding. Ten of these SNPs segregated in a Duroc commercial population ( n  = 350) for which lipid metabolism and meat and carcass quality trait records were available. Significant associations were found between two linked single nucleotide polymorphisms (c.4899G>A and c.5196T>C) and percentages of carcass lean, intramuscular fat, monounsaturated, saturated (myristic, palmitic and stearic) and polyunsaturated (linoleic) FAs in the longissimus thoracis et lumborum muscle, along with serum HDL-cholesterol concentration. The most important allele substitution effects were observed for the polyunsaturated/saturated FA ratio (13–21% of the phenotypic mean) as well as for the percentages of ω-6 and polyunsaturated FAs, especially linoleic acid (7–16% of the phenotypic mean). These results suggest the existence of a causal mutation, mapping to the chromosomal region containing the pig ACACA gene, with marked effects on FA composition of meat.     

The Importance of the Human Footprint in Shaping the Global Distribution of Terrestrial,Freshwater and Marine Invaders

Human activities such as transport, trade and tourism are likely to influence the spatial distribution of non-native species and yet, Species Distribution Models (SDMs) that aim to predict the future broad scale distribution of invaders often rely on environmental (e.g. climatic) information only. This study investigates if and to what extent do human activities that directly or indirectly influence nature (hereafter the human footprint) affect the global distribution of invasive species in terrestrial, freshwater and marine ecosystems. We selected 72 species including terrestrial plants, terrestrial animals, freshwater and marine invasive species of concern in a focus area located in NW Europe (encompassing Great Britain, France, The Netherlands and Belgium). Species Distribution Models were calibrated with the global occurrence of species and a set of high-resolution (9×9 km) environmental (e.g. topography, climate, geology) layers and human footprint proxies (e.g. the human influence index, population density, road proximity). Our analyses suggest that the global occurrence of a wide range of invaders is primarily limited by climate. Temperature tolerance was the most important factor and explained on average 42% of species distribution. Nevertheless, factors related to the human footprint explained a substantial amount (23% on average) of species distributions. When global models were projected into the focus area, spatial predictions integrating the human footprint featured the highest cumulative risk scores close to transport networks (proxy for invasion pathways) and in habitats with a high human influence index (proxy for propagule pressure). We conclude that human related information–currently available in the form of easily accessible maps and databases—should be routinely implemented into predictive frameworks to inform upon policies to prevent and manage invasions. Otherwise we might be seriously underestimating the species and areas under highest risk of future invasions.     

Drowning Mortality and Morbidity Rates in Children and Adolescents 0-19yrs: A Population-Based Study in Queensland,Australia

ObjectiveTo redress the lack of Queensland population incidence mortality and morbidity data associated with drowning in those aged 0-19yrs, and to understand survival and patient care.ResultsDrowning death to survival ratio was 1:10, and two out of three of those who survived were admitted to hospital. Incidence rates for fatal and non-fatal drowning increased over time, primarily due to an increase in non-fatal drowning. There were non-significant reductions in fatal and admission rates. Rates for non-fatal drowning that did not result in hospitalisation more than doubled over the seven years. Children aged 5-9yrs and 10-14yrs incurred the lowest incidence rates 6.38 and 4.62 (expressed as per 100,000), and the highest rates were among children aged 0-4yrs (all drowning events 43.90; fatal 4.04; non-fatal 39.85–comprising admission 26.69 and non-admission 13.16). Males were over-represented in all age groups except 10-14yrs. Total male drowning events increased 44% over the seven years (P<0.001).ConclusionThis state-wide data collection has revealed previously unknown incidence and survival ratios. Increased trends in drowning survival rates may be viewed as both positive and challenging for drowning prevention and the health system. Males are over-represented, and although infants and toddlers did not have increased fatality rates, they had the greatest drowning burden demonstrating the need for continued drowning prevention efforts.     

Belongingness in Early Secondary School: Key Factors that Primary and Secondary Schools Need to Consider

It is unknown if, and how, students redefine their sense of school belongingness after negotiating the transition to secondary school. The current study used longitudinal data from 266 students with, and without, disabilities who negotiated the transition from 52 primary schools to 152 secondary schools. The study presents the 13 most significant personal student and contextual factors associated with belongingness in the first year of secondary school. Student perception of school belongingness was found to be stable across the transition. No variability in school belongingness due to gender, disability or household-socio-economic status (SES) was noted. Primary school belongingness accounted for 22% of the variability in secondary school belongingness. Several personal student factors (competence, coping skills) and school factors (low-level classroom task-goal orientation), which influenced belongingness in primary school, continued to influence belongingness in secondary school. In secondary school, effort-goal orientation of the student and perception of their school’s tolerance to disability were each associated with perception of school belongingness. Family factors did not influence belongingness in secondary school. Findings of the current study highlight the need for primary schools to foster belongingness among their students at an early age, and transfer students’ belongingness profiles as part of the hand-over documentation. Most of the factors that influenced school belongingness before and after the transition to secondary are amenable to change.     

Embryonic Lethality in Homozygous Human Her-2 Transgenic Mice Due to Disruption of the Pds5b Gene

The development of antigen-targeted therapeutics is dependent on the preferential expression of tumor-associated antigens (TAA) at targetable levels on the tumor. Tumor-associated antigens can be generated de novo or can arise from altered expression of normal basal proteins, such as the up-regulation of human epidermal growth factor receptor 2 (Her2/ErbB2). To properly assess the development of Her2 therapeutics in an immune tolerant model, we previously generated a transgenic mouse model in which expression of the human Her2 protein was present in both the brain and mammary tissue. This mouse model has facilitated the development of Her2 targeted therapies in a clinically relevant and suitable model. While heterozygous Her2^+/- mice appear to develop in a similar manner to wild type mice (Her2^-/-), it has proven difficult to generate homozygous Her2^+/+ mice, potentially due to embryonic lethality. In this study, we performed whole genome sequencing to determine if the integration site of the Her2 transgene was responsible for this lethality. Indeed, we report that the Her2 transgene had integrated into the Pds5b (precocious dissociation of sisters) gene on chromosome 5, as a 162 copy concatemer. Furthermore, our findings demonstrate that Her2^+/+ mice, similar to Pds5b^-/- mice, are embryonic lethal and confirm the necessity for Pds5b in embryonic development. This study confirms the value of whole genome sequencing in determining the integration site of transgenes to gain insight into associated phenotypes.