Association of Versican Turnover with All-Cause Mortality in Patients on Haemodialysis

Objective

Cardiovascular diseases are among the most common causes of mortality in renal failure patients undergoing haemodialysis. A high turnover rate of the proteoglycan versican, represented by the increased presence of its fragmentation products in plasma, has previously been associated with cardiovascular diseases. The objective of the study was to investigate the association of versican turnover assessed in plasma with survival in haemodialysis patients.

Methods

A specific matrix metalloproteinase-generated neo-epitope fragment of versican (VCANM) was measured in plasma of 364 haemodialysis patients with a 5-years follow-up, using a robust competitive enzyme-linked immunosorbent assays. Association between VCANM plasma concentration and survival was assessed by Kaplan-Meier analysis and adjusted Cox model.

Results

Haemodialysis patients with plasma VCANM concentrations in the lowest quartile had increased risk of death (odds ratio, as compared to the highest quartile: 7.1, p<0.001), with a reduced survival of 152 days compared to 1295 days for patients with plasma VCANM in the highest quartile. Multivariate analysis showed that low VCANM (p<0.001) and older age (p<0.001) predicted death in haemodialysis patients.

Conclusions

Low concentrations of the versican fragment VCANM in plasma were associated with higher risk of death among haemodialysis patients. A possible protective role for the examined versican fragment is suggested.     

Habitat Selection Response of Small Pelagic Fish in Different Environments. Two Examples from the Oligotrophic Mediterranean Sea

A number of scientific papers in the last few years singled out the influence of environmental conditions on the spatial distribution of fish species, highlighting the need for the fisheries scientific community to investigate, besides biomass estimates, also the habitat selection of commercially important fish species. The Mediterranean Sea, although generally oligotrophic, is characterized by high habitat variability and represents an ideal study area to investigate the adaptive behavior of small pelagics under different environmental conditions. In this study the habitat selection of European anchovy Engraulis encrasicolus and European sardine Sardina pilchardus is analyzed in two areas of the Mediterranean Sea that largely differentiate in terms of environmental regimes: the Strait of Sicily and the North Aegean Sea. A number of environmental parameters were used to investigate factors influencing anchovy and sardine habitat selection. Acoustic surveys data, collected during the summer period 2002–2010, were used for this purpose. The quotient analysis was used to identify the association between high density values and environmental variables; it was applied to the entire dataset in each area in order to identify similarities or differences in the “mean” spatial behavioral pattern for each species. Principal component analysis was applied to selected environmental variables in order to identify those environmental regimes which drive each of the two ecosystems. The analysis revealed the effect of food availability along with bottom depth selection on the spatial distribution of both species. Furthermore PCA results highlighted that observed selectivity for shallower waters is mainly associated to specific environmental processes that locally increase productivity. The common trends in habitat selection of the two species, as observed in the two regions although they present marked differences in hydrodynamics, seem to be driven by the oligotrophic character of the study areas, highlighting the role of areas where the local environmental regimes meet ‘the ocean triad hypothesis’.     

Prenyloxyphenylpropanoids as a novel class of anticonvulsive agents

In this study, we synthesized some natural and semi-synthetic prenyloxyphenylpropanoids (e.g., acetophenones, benzoic and cinnamic acids, chalcones, and coumarins), and we assessed their in vivo neuroprotective activity, using the mouse maximal electroshock-induced seizure model (MES test). 7-Isopentenyloxycoumarin and (2E)-3-{4-[(3-methylbut-2-enyl)oxy]phenyl}prop-2-enoic acid, administered ip at a dose of 300 mg/kg, suppressed MES-induced seizures in mice in a time- and dose-dependent manner.     

Effects of human transforming growth factors on topoisomerases from normal fibroblasts

Normal rat kidney fibroblasts (NRK-B F49) treated at transforming doses with a gamma-like TGF, partially purified from human melanoma, showed a 3 to 5 fold increase in DNA type II topoisomerase activity. A similar effect was observed using EGF and a partially purified alfa TGF from rabbit fetuses. DNA type I topoisomerase activity, from the same cells, was not significantly modified by treatment with these growth factors. Topoisomerase II stimulation was dependent on mRNA synthesis. The possible role of topoisomerase II in phenotypical cell transformation induced by TGF is discussed.     

Erythropoietin production by the liver in fetal-neonatal life.

Subtotal ablation of the liver in 10-day-old ($\text{i.e.}$, neonate) rats resulted in almost complete abolition of the erythropöietin (Ep) response to a 6-hr bout of hypoxia, starting 1 hr after the operation. Partial or subtotal liver regeneration on day 2 or 3 post-hepatectomy was correlated respectively with partial or subtotal restoration of Ep production. Ablätion of the spleen or kidneys in 7- or 10-day-old rats did not modify hypoxic Ep levels. It is concluded that the liver is the main or exclusive source of Ep in the neonate rat, and possibly represents the main site of hormonal production in fetal-neonatal life of mammals.     

Protein degradation fragments as diagnostic and prognostic biomarkers of connective tissue diseases: understanding the extracellular matrix message and implication for current and future serological biomarkers

The aim of this review is to discuss the potential usefulness of novel biochemical markers of connective tissues: neo-epitopes of extracellular matrix proteins generated by post-translational modifications by tissue proteinases. As each modification results from a specific local physiological or pathobiological process, the identification of specific proteinase-mediated cleavage products of tissue-specific proteins may produce a unique disease-specific biochemical marker. The authors present a novel interpretation of the process of tissue degradation described by neo-epitope fragments of the interstitial and basement membrane matrix in fibrotic disease, and the diagnostic and prognostic potential of such markers. Moreover, the authors highlight the importance of matrix protein fragments not only as markers of tissue remodeling, but also as players in tissue remodeling, due to their signaling properties.     

Bioremediation of benzene,toluene, ethylbenzene,xylenes-contaminated soil: a biopile pilot experiment

Aims: In this study, we evaluated the removal efficiency of fuel hydrocarbons from a jet fuel contaminated area using bioaugmentation treatment in biopile. Methods and Results: The hydrocarbon analysis of the sample revealed total hydrocarbons mainly constituted by benzene, toluene, ethylbenzene, xylenes (BTEX) and heavy aliphatic hydrocarbons. Enrichments of soil sample were performed with BTEX, pristane and fuel JP-5, respectively, selected hydrocarbon-degrading strains, namely Acinetobacter sp., Pseudomonas sp. and Rhodococcus sp. Three hundred litres of culture containing 10⁸ cell ml⁻¹ of each strain and nutrients sprayed on the biopile allowed a removal of 90% of total hydrocarbons in 15 days. Bioremediation process was monitored by observation of the respiration rate and the bacterial abundance and GC-MS analysis. Conclusions: The efficiency of the treatment in the biopile was considerable. The assessment of microbial activity during the experiment is necessary for interventions targeted to improve environmental parameters such as humidity, temperature, pH and nutrients for optimization of the bioremediation process. Significance and Impact of the Study: A better knowledge of microbial successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in biopile study improve our understanding of processes occurring during oil pollution.     

A comparison of apparent mRNA half-life using kinetic labeling techniques vs decay following administration of transcriptional inhibitors.

Several different techniques were used to determine the apparent half-lives of immunoglobulin gamma 2b heavy chain and kappa light chain mRNA's in mouse myeloma 4T001 and a mutant derived from 4T001, i.e., mutant I17. The mutant I17 Ig heavy chain mRNA lacks CH1 and has fused CH2 and CH3 domains resulting in a truncated protein. By all four techniques the Ig heavy chain mRNA from mutant I17 displays a half-life that is approximately 70% the half-life of Ig mRNA in 4T001 cells. However, the absolute values of apparent half-life varied by greater than twofold for both lines among several of the techniques employed. The half-life of Ig gamma 2b mRNA in 4T001 cells was found to be 6.4 h by measuring decay following administration of the adenosine analog DRB to block new mRNA synthesis and 5.7 hr by measuring accumulation in an approach to steady-state labeling protocol. In contrast, the observed Ig mRNA half-lives determined by measuring decay following administration of actinomycin D to block new mRNA synthesis, or in a pulse-chase analysis were 2.9 and 3.8 h, respectively. The apparent half-life for Ig kappa light chain mRNA was the same in the 4T001 and I17 lines using any one technique but the value varied depending on the technique from a high value of 5.9 h following DRB to a low value of 2.4 h with actinomycin decay. Approach to steady-state is theoretically the most accurate method to measure mRNA half-life when that value is less than the doubling time of the cells. Pulse-chase analyses are accurate for measuring mRNA half-life when that value is longer than the effective chase period. Measuring preformed message decay following administration of drugs to block new mRNA synthesis is adaptable over a range of half-lives, but the cells must be shown to retain correct RNA metabolism over the time frame of the experiment. Determining a correct half-life for a particular mRNA may not be feasible using only one method and may, in fact, require several different approaches until a consensus value emerges.