Minimal variation of the plasma lipidome after delayed processing of neonatal cord blood

Background

Cord blood lipids are potential disease biomarkers. We aimed to determine if their concentrations were affected by delayed blood processing.

Method

Refrigerated cord blood from six healthy newborns was centrifuged every 12 h for 4 days. Plasma lipids were analysed by liquid chromatography/mass spectroscopy.

Results

Of 262 lipids identified, only eight varied significantly over time. These comprised three dihexosylceramides, two phosphatidylserines and two phosphatidylethanolamines whose relative concentrations increased and one sphingomyelin that decreased.

Conclusion

Delay in separation of plasma from refrigerated cord blood has minimal effect overall on the plasma lipidome.

     

Rudgea viburnoides (Rubiaceae) overcomes the low soil fertility of the Brazilian Cerrado and hyperaccumulates aluminum in cell walls and chloroplasts

Plant and Soil - Rudgea viburnoides (Cham.) Benth. is an aluminum (Al) hyperaccumulator species native to the Brazilian Cerrado and can be found on soils with different fertilities and Al...     

Dihydroceramide accumulation and reactive oxygen species are distinct and nonessential events in 4-HPR-mediated leukemia cell death

4-(Hydroxyphenyl)retinamide (4-HPR) is a synthetic retinoid with a strong apoptotic effect towards different cancer cell lines in vitro, and it is currently tested in clinical trials. Increases of reactive oxygen species (ROS) and modulation of endogenous sphingolipid levels are well-described events observed upon 4-HPR treatment, but there is still a lack of understanding of their relationship and their contribution to cell death. LC-MS analysis of sphingolipids revealed that in human leukemia CCRF-CEM and Jurkat cells, 4-HPR induced dihydroceramide but not ceramide accumulation even at sublethal concentrations. Myriocin prevented the 4-HPR-induced dihydroceramide accumulation, but it did not prevent the loss of viability and increase of intracellular ROS production. On the other hand, ascorbic acid, Trolox, and vitamin E reversed 4-HPR effects on cell death but not dihydroceramide accumulation. NDGA, described as a lipoxygenase inhibitor, exerted a significantly higher antioxidant activity than vitamin E and abrogated 4-HPR-mediated ROS. It did not however rescue cellular viability. Taken together, this study demonstrates that early changes observed upon 4-HPR treatment, i.e., sphingolipid modulation and ROS production, are mechanistically independent events. Furthermore, the results indicate that 4-HPR-driven cell death may occur even in the absence of dihydroceramide or ROS accumulation. These observations should be taken into account for an improved design of drug combinations.     

Phylogenomic analyses support the monophyly of Taphrinomycotina, including Schizosaccharomyces fission yeasts

Several morphologically dissimilar ascomycete fungi includingSchizosaccharomyces, Taphrina, Saitoella, Pneumocystis, andNeolecta have been grouped into the taxon Taphrinomycotina (Archiascomycotaor Archiascomycotina), originally based on rRNA phylogeny. Theseanalyses lack statistically significant support for the monophylyof this grouping, and although confirmed by more recent multigeneanalyses, this topology is contradicted by mitochondrial phylogenies.To resolve this inconsistency, we have assembled phylogenomicmitochondrial and nuclear data sets from four distantly relatedtaphrinomycotina taxa: Schizosaccharomyces pombe, Pneumocystiscarinii, Saitoella complicata, and Taphrina deformans. Our phylogenomicanalyses based on nuclear data (113 proteins) conclusively supportthe monophyly of Taphrinomycotina, diverging as a sister groupto Saccharomycotina + Pezizomycotina. However, despite the improvedtaxon sampling, Taphrinomycotina continue to be paraphyleticwith the mitochondrial data set (13 proteins): Schizosaccharomycesspecies associate with budding yeasts (Saccharomycotina) andthe other Taphrinomycotina group as a sister group to Saccharomycotina+ Pezizomycotina. Yet, as Schizosaccharomyces and Saccharomycotinaspecies are fast evolving, the mitochondrial phylogeny may beinfluenced by a long-branch attraction (LBA) artifact. Afterremoval of fast-evolving sequence positions from the mitochondrialdata set, we recover the monophyly of Taphrinomycotina. Ourcombined results suggest that Taphrinomycotina is a legitimatetaxon, that this group of species diverges as a sister groupto Saccharomycotina + Pezizomycotina, and that phylogeneticpositioning of yeasts and fission yeasts with mitochondrialdata is plagued by a strong LBA artifact.     

Role of Haptoglobin in Polycystic Ovary Syndrome (PCOS), Obesity and Disorders of Glucose Tolerance in Premenopausal Women

Background

Hp² alleles of the haptoglobin α–chain polymorphism reduce the anti-oxidant properties and increase the pro-inflammatory actions of this acute-phase protein in a gene-dosage fashion. We hypothesized that the haptoglobin polymorphism might contribute to the increased oxidative stress and low-grade chronic inflammation frequently associated with polycystic ovary syndrome, obesity, and abnormalities of glucose tolerance.

Methodology/Principal Findings

Serum haptoglobin and the haptoglobin α–chain polymorphism were determined in 141 patients with polycystic ovary syndrome and 102 non-hyperandrogenic women. Of the whole group of 243 premenopausal women, 117 were obese and 51 showed abnormal glucose tolerance. Although serum haptoglobin concentrations were similar in PCOS patients and controls, the former presented with an increased frequency of Hp² alleles (62% vs. 52%, P = 0.023). Circulating haptoglobin levels increased with obesity (P<0.001), yet no association was found between obesity and haptoglobin genotypes. No differences were observed in haptoglobin levels or genotype frequencies depending on glucose tolerance. Fifty percent of the variation in serum haptoglobin concentrations was explained by the variability in serum C-reactive protein concentrations, BMI, insulin sensitivity and haptoglobin genotypes.

Conclusions/Significance

Serum haptoglobin concentrations in premenopausal women are largely dependent on the haptoglobin polymorphism and on the presence of obesity, with insulin resistance and chronic inflammation possibly modulating this relationship. The association of polycystic ovary syndrome with Hp² alleles suggests that the anti-oxidant and anti-inflammatory properties of haptoglobin may be reduced in these patients.     

Effects of morphine administration and its withdrawal on rat brain aminopeptidase activities

The endogenous opioid neuropeptide system seems to be involved in the neural processes which underlie drug addiction. Several studies have reported that the administration of morphine induces changes in the levels and/or activity of endogenous opioid peptides (enkephalin, dynorphin) and their precursors in specific brain regions of the adult CNS. The aim of this work was to study the effects of chronic morphine exposure and its withdrawal on certain aminopeptidases capable of degrading opioid peptides in brain areas including the amygdala, hypothalamus, hippocampus, striatum and brain cortices. In animals treated with morphine, aminopeptidase N presented higher enzyme activity levels in the striatum, the hypothalamus and the amygdala compared to control animals, although statistically significant differences were observed only in the case of the striatum. In addition, the activity of soluble puromycin-sensitive aminopeptidase (PSA) was found to be higher in the frontal cortex of these rats. In contrast, rats experiencing withdrawal symptoms presented decreased levels of aminopeptidase activity in certain brain areas. Thus, the activity of aminopeptidase N in the hippocampus and soluble puromycin-sensitive aminopeptidase in the frontal cortex were found to be lower in rats experiencing naloxone precipitated withdrawal symptoms, compared to the corresponding controls. Finally, the activity of the three studied aminopeptidases in vitro was unaltered by incubation with morphine, suggesting that the observed effects are not due to a direct action of this opioid upon the aminopeptidases. The results of the present report indicate that aminopeptidases may play an important role in the processes of tolerance and withdrawal associated with morphine administration.     

Monophyly of primary photosynthetic eukaryotes: green plants, red algae, and glaucophytes

Between 1 and 1.5 billion years ago, eukaryotic organisms acquired the ability to convert light into chemical energy through endosymbiosis with a Cyanobacterium (e.g.,). This event gave rise to "primary" plastids, which are present in green plants, red algae, and glaucophytes ("Plantae" sensu Cavalier-Smith). The widely accepted view that primary plastids arose only once implies two predictions: (1) all plastids form a monophyletic group, as do (2) primary photosynthetic eukaryotes. Nonetheless, unequivocal support for both predictions is lacking (e.g.,). In this report, we present two phylogenomic analyses, with 50 genes from 16 plastid and 15 cyanobacterial genomes and with 143 nuclear genes from 34 eukaryotic species, respectively. The nuclear dataset includes new sequences from glaucophytes, the less-studied group of primary photosynthetic eukaryotes. We find significant support for both predictions. Taken together, our analyses provide the first strong support for a single endosymbiotic event that gave rise to primary photosynthetic eukaryotes, the Plantae. Because our dataset does not cover the entire eukaryotic diversity (but only four of six major groups in), further testing of the monophyly of Plantae should include representatives from eukaryotic lineages for which currently insufficient sequence information is available.     

Recurrent seasonal changes in bacterial growth efficiency,metabolism and community composition in coastal waters

The microbial response to environmental changes in coastal waters of the eastern Cantabrian Sea was explored for four years by analysing a broad set of environmental variables along with bacterial community metabolism and composition. A recurrent seasonal cycle emerged, consisting of two stable periods, characterized by low bacterial metabolic activity (winter) from October to March, and high bacterial metabolic activity (summer) from May to August. These two contrasting periods were linked by short transition periods in April (T_A) and September (T_S). The phylogenetic groups Alphaproteobacteria and Bacteroidetes were dominant during winter and summer respectively, and their recurrent alternation was mainly driven by the bloom of eukaryotic phytoplankton before T_A and the bloom of prokaryotic phytoplankton before T_S. Bacterial growth efficiency remained high and stable during the winter and summer periods but dropped during the two short transition periods. Our results suggest that bacterial growth efficiency should be considered a very resilient property that reflects different stages in the adaptation of the bacterial community composition to the environmental changes occurring throughout the seasonal cycle in this coastal ecosystem.     

Role of Thiobacillus thioparus in the biodegradation of carbon disulfide in a biofilter packed with a recycled organic pelletized material

This study reports the biodegradation of carbon disulfide (CS₂) in air biofilters packed with a pelletized mixture of composted manure and sawdust. Experiments were carried out in two lab-scale (1.2 L) biofiltration units. Biofilter B was seeded with activated sludge enriched previously on CS₂-degrading biomass under batch conditions, while biofilter A was left as a negative inoculation control. This inoculum was characterized by an acidic pH and sulfate accumulation, and contained Achromobacter xylosoxidans as the main putative CS₂ biodegrading bacterium. Biofilter operation start-up was unsuccessfully attempted under xerophilic conditions and significant CS₂ elimination was only achieved in biofilter A upon the implementation of an intermittent irrigation regime. Sustained removal efficiencies of 90–100 % at an inlet load of up to 12 g CS₂ m^?3 h^?1 were reached. The CS₂ removal in this biofilter was linked to the presence of the chemolithoautotrophic bacterium Thiobacillus thioparus, known among the relatively small number of species with a reported capacity of growing on CS₂ as the sole energy source. DGGE molecular profiles confirmed that this microbe had become dominant in biofilter A while it was not detected in samples from biofilter B. Conventional biofilters packed with inexpensive organic materials are suited for the treatment of low-strength CS₂ polluted gases (IL <12 g CS₂ m^?3 h^?1), provided that the development of the adequate microorganisms is favored, either upon enrichment or by inoculation. The importance of applying culture-independent techniques for microbial community analysis as a diagnostic tool in the biofiltration of recalcitrant compounds has been highlighted.