Effect of soil/contamination characteristics and process operational conditions on aminopolycarboxylates enhanced soil washing for heavy metals removal: a review

The present paper analyzes literature data dealing with the use of aminopolycarboxylates for chemical washing of heavy metals contaminated soils. The aim is to rationalize and organize the up-to-date knowledge of process dependence on different parameters, in order to give a contribution to the development of washing protocols applicable for process optimization. Process efficiency is found to be dependent on i) parameters related to soil composition, ii) parameters related to contaminant characteristics and iii) operating parameters. The effect that each of them, according to the reviewed experimental studies, has on process efficiency, is highlighted, and the interdependence among them is presented as a key point to understand the overall removal mechanism and therefore to calibrate its application case-by-case.     

Grafted Neural Precursors Integrate Into Mouse Striatum,Differentiate and Promote Recovery of Function Through Release of Erythropoietin in MPTP-Treated Mice

Erythropoietin-releasing neural precursor cells (Er-NPCs) are a subclass of subventricular zone-derived neural progenitors, capable of surviving for 6 hr after death of donor. They present higher neural differentiation. Here, Er-NPCs were studied in animal model of Parkinson’s disease. Dopaminergic degeneration was caused by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intraperitoneal administration in C57BL/6 mice. The loss of function was evaluated by specific behavioral tests. Er-NPCs (2.5 × 10⁵) expressing the green fluorescent protein were administered by stereotaxic injection unilaterally in the left striatum. At the end of observational research period (2 weeks), most of the transplanted Er-NPCs were located in the striatum, while several had migrated ventrally and caudally from the injection site, up to ipsilateral and contralateral substantia nigra. Most of transplanted cells had differentiated into dopaminergic, cholinergic, or GABAergic neurons. Er-NPCs administration also promoted a rapid functional improvement that was already evident at the third day after cells administration. This was accompanied by enhanced survival of nigral neurons. These effects were likely promoted by Er-NPCs-released erythropoietin (EPO), since the injection of Er-NPCs in association with anti-EPO or anti-EPOR antibodies had completely neutralized the recovery of function. In addition, intrastriatal administration of recombinant EPO mimics the effects of Er-NPCs. We suggest that Er-NPCs, and cells with similar properties, may represent good candidates for cellular therapy in neurodegenerative disorders of this kind.     

Extending RAD tag analysis to microbial ecology: a comparison between MultiLocus Sequence Typing and 2b‐RAD to investigate Listeria monocytogenes genetic structure

The advent of next‐generation sequencing (NGS) has dramatically changed bacterial typing technologies, increasing our ability to differentiate bacterial isolates. Despite it is now possible to sequence a bacterial genome in a few days and at reasonable costs, most genetic analyses do not require whole‐genome sequencing, which also remains impractical for large population samples due to the cost of individual library preparation and bioinformatics. More traditional sequencing approaches, however, such as MultiLocus Sequence Typing (mlst ) are quite laborious and time‐consuming, especially for large‐scale analyses. In this study, a genotyping approach based on restriction site‐associated (RAD) tag sequencing, 2b‐RAD, was applied to characterize Listeria monocytogenes strains. To verify the feasibility of the method, an in silico analysis was performed on 30 available complete genomes. For the same set of strains, in silico mlst analysis was conducted as well. Subsequently, 2b‐RAD and mlst analyses were experimentally carried out on 58 isolates collected from food samples or food‐processing sites. The obtained results demonstrate that 2b‐RAD predicts mlst types and often provides more detailed information on population structure than mlst . Moreover, the majority of variants differentiating identical sequence type isolates mapped against accessory fragments, thus providing additional information to characterize strains. Although mlst still represents a reliable typing method, large‐scale studies on molecular epidemiology and public health, as well as bacterial phylogenetics, population genetics and biosafety could benefit of a low cost and fast turnaround time approach such as the 2b‐RAD analysis proposed here.     

K+ Channel Inhibition Differentially Regulates Migration of Intestinal Epithelial Cells in Inflamed vs. Non-Inflamed Conditions in a PI3K/Akt-Mediated Manner

Background

Potassium channels have been shown to determine wound healing in different tissues, but their role in intestinal epithelial restitution–the rapid closure of superficial wounds by intestinal epithelial cells (IEC)–remains unclear.

Methods

In this study, the regulation of IEC migration by potassium channel modulation was explored with and without additional epidermal growth factor (EGF) under baseline and interferon-γ (IFN-γ)-pretreated conditions in scratch assays and Boyden chamber assays using the intestinal epithelial cell lines IEC-18 and HT-29. To identify possibly involved subcellular pathways, Western Blot (WB)-analysis of ERK and Akt phosphorylation was conducted and PI3K and ERK inhibitors were used in scratch assays. Furthermore, mRNA-levels of the potassium channel KCNN4 were determined in IEC from patients suffering from inflammatory bowel diseases (IBD).

Results

Inhibition of Ca²⁺-dependent potassium channels significantly increased intestinal epithelial restitution, which could not be further promoted by additional EGF. In contrast, inhibition of KCNN4 after pretreatment with IFN-γ led to decreased or unaffected migration. This effect was abolished by EGF. Changes in Akt, but not in ERK phosphorylation strongly correlated with these findings and PI3K but not ERK inhibition abrogated the effect of KCNN4 inhibition. Levels of KCNN4 mRNA were higher in samples from IBD patients compared with controls.

Conclusions

Taken together, we demonstrate that inhibition of KCNN4 differentially regulates IEC migration in IFN-γ-pretreated vs. non pretreated conditions. Moreover, our data propose that the PI3K signaling cascade is responsible for this differential regulation. Therefore, we present a cellular model that contributes new aspects to epithelial barrier dysfunction in chronic intestinal inflammation, resulting in propagation of inflammation and symptoms like ulcers or diarrhea.     

Antitumor activity and COMPARE analysis of bis-indole derivatives

This paper reports the synthesis of new derivatives (formed by two indole systems separated by a central moiety) analogous of potent antitumor agents previously described. The activity of the bis-indoles bearing a pyridine core confirms the good result described in the previous paper and compound 4c was chosen for the first in vivo experiment (Hollow Fiber Assay). COMPARE analysis and structure–activity relationships were also considered. Contrary to data reported by other Authors, no correlations were found between antitumor activity and NQO1 induction.     

Molecular regulation of vertebrate retina cell fate

The specification of retinal cell fate is a multistep process that begins during early development and results from the spatio‐temporal coordination of cell cycle, cell differentiation, and morphogenesis. This review focuses on recent advances in understanding the molecular mechanisms underlying the distinct steps of retinal specification. Emphasis is placed on key regulatory events that control the multipotency of retinal progenitors, the generation of cell diversity, and the establishment of the clock that determines the ordered generation of retinal cell types. These basic studies have paved the way to the latest progress on the isolation and in vitro generation of retinal stem cells, which is presented in the light of possible therapeutic applications. Birth Defects Research (Part C) 87:284–295, 2009. © 2009 Wiley‐Liss, Inc.     

Effects of methylglyoxal on platelet hydrogen peroxide accumulation,aggregation and release reaction

Methylglyoxal generates a slight increase in the basal level of hydrogen peroxide in platelets. The oxidation effect of methylglyoxal significantly potentiated by thrombin, depends on both the ketoaldehyde and the agonist concentrations. A further significant increase in hydrogen peroxide accumulation was obtained in platelets pretreated with the alkylating agent N-ethylmaleimide which depletes GSH and blocks glutathione peroxidase. Resting platelets completely transform the ketoaldehyde into D (?)lactate, whereas stimulated platelets transform about 10–15 per cent of the metabolized methylglyoxal into D (?)lactate. The metabolic modifications generated by methylglyoxal such as the GSH depletion and hydrogen peroxide accumulation induce modifications in platelet function. Methylglyoxal inhibits platelet aggregation induced by several agonists and ATP release induced by thrombin.     

Bayesian Weighing of Electron Cryo-Microscopy Data for Integrative Structural Modeling

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