Fishers’ ecological knowledge on the reproduction of fish and shrimp in a subtropical coastal ecosystem

Hydrobiologia - Fishers’ ecological knowledge (FEK) has contributed to a better understanding about the reproduction of fishery resources, especially where biological data are scarce or...     

Interleukin-15 is a major regulator of the cell-microenvironment interactions in human renal homeostasis

Experiments in IL-15^?/? and IL-15Rα^?/? mice show that intra-renal IL-15, through IL-15Rα behaves as an epithelial survival factor. Recent data highlight new functions of IL-15 in renal homeostasis mediated by IL-15Rγ (CD132). Indeed, in CD132+ renal epithelial tubular cells IL-15 preserves E-cadherin expression inhibiting epithelial-mesenchymal transition (EMT). By contrast, during allograft rejection, the increased intra-graft IL-15 expression favors tubular destruction facilitating the intraepithelial recruitment of CD8 T cells expressing the E-cadherin ligand CD103. In renal cancer, loss of CD132 by epithelial cells defines a tumoral microenvironment where IL-15 triggers E-cadherin down-regulation and EMT. Finally, in CD132+ renal cancer stem cells IL-15 induces the generation of non-tumorigenic epithelial cells sensitive to cytotoxic drugs. These findings are discussed in the light of IL-15-based immunotherapy for renal cancer.     

Exendin-4 Induces Cell Adhesion and Differentiation and Counteracts the Invasive Potential of Human Neuroblastoma Cells

Exendin-4 is a molecule currently used, in its synthetic form exenatide, for the treatment of type 2 diabetes mellitus. Exendin-4 binds and activates the Glucagon-Like Peptide-1 Receptor (GLP-1R), thus inducing insulin release. More recently, additional biological properties have been associated to molecules that belong to the GLP-1 family. For instance, Peptide YY and Vasoactive Intestinal Peptide have been found to affect cell adhesion and migration and our previous data have shown a considerable actin cytoskeleton rearrangement after exendin-4 treatment. However, no data are currently available on the effects of exendin-4 on tumor cell motility. The aim of this study was to investigate the effects of this molecule on cell adhesion, differentiation and migration in two neuroblastoma cell lines, SH-SY5Y and SK-N-AS. We first demonstrated, by Extra Cellular Matrix cell adhesion arrays, that exendin-4 increased cell adhesion, in particular on a vitronectin substrate. Subsequently, we found that this molecule induced a more differentiated phenotype, as assessed by i) the evaluation of neurite-like protrusions in 3D cell cultures, ii) the analysis of the expression of neuronal markers and iii) electrophysiological studies. Furthermore, we demonstrated that exendin-4 reduced cell migration and counteracted anchorage-independent growth in neuroblastoma cells. Overall, these data indicate for the first time that exendin-4 may have anti-tumoral properties.     

Tyrosinase and Layer-by-Layer supported tyrosinases in the synthesis of lipophilic catechols with antiinfluenza activity

Catechol derivatives with lipophilic properties have been selectively synthesized by tyrosinase in high yield avoiding long and tedious protection/deprotection steps usually required in traditional procedures. The synthesis was effective also with immobilized tyrosinase able to perform for more runs. The novel catechols were evaluated against influenza A virus, that continue to represent a severe threat worldwide. A significant antiviral activity was observed in derivatives characterized by antioxidant activity and long carbon alkyl side-chains, suggesting the possibility of a new inhibition mechanism based on both redox and lipophilic properties.     

Isoprene is more affected by climate drivers than monoterpenes: A meta‐analytic review on plant isoprenoid emissions

Isoprene and monoterpenes (MTs) are among the most abundant and reactive volatile organic compounds produced by plants (biogenic volatile organic compounds). We conducted a meta‐analysis to quantify the mean effect of environmental factors associated to climate change (warming, drought, elevated CO₂, and O₃) on the emission of isoprene and MTs. Results indicated that all single factors except warming inhibited isoprene emission. When subsets of data collected in experiments run under similar change of a given environmental factor were compared, isoprene and photosynthesis responded negatively to elevated O₃ (?8% and ?10%, respectively) and drought (?15% and ?42%), and in opposite ways to elevated CO₂ (?23% and +55%) and warming (+53% and ?23%, respectively). Effects on MTs emission were usually not significant, with the exceptions of a significant stimulation caused by warming (+39%) and by elevated O₃ (limited to O₃‐insensitive plants, and evergreen species with storage organs). Our results clearly highlight individual effects of environmental factors on isoprene and MT emissions, and an overall uncoupling between these secondary metabolites produced by the same methylerythritol 4‐phosphate pathway. Future results from manipulative experiments and long‐term observations may help untangling the interactive effects of these factors and filling gaps featured in the current meta‐analysis.     

Differential responses in vitro of rice cultivars to Italian lineages of the blast pathogen Pyricularia grisea (Cooke) Sacc. 1. Oxidative burst

Suspension cultured cells of six rice cultivars differing in their sensitivity to blast were treated with mycelial wall hydrolysates prepared from seven isolates belonging to different Pyricularia grisea lineages. Soon after elicitor addition, rice cells produced significant amounts of superoxide anion, which was rapidly converted into diffusible peroxide. Maximal effects were achieved at 50 mg L-1 elicitor. In all cases, a 7 to 13-fold increase in the basal rate of reactive oxygen species production was found. Neither differential effects among strains nor clear relationships between lineage and the resulting oxidative burst were evident. Interestingly, a good correlation was found between basal (and elicited) levels of peroxide generation and the overall tolerance of rice cultivars to the pathogen. About two days after elicitation, cell death occurred proportional to the amount of hydrogen peroxide released. Peroxide was required to trigger loss of cell viability, but the latter was not due to a direct toxic effect, suggesting the induction of programmed cell death. Results represent the first data aimed to develop in vitro tests for pathogenicity prediction of Italian blast lineages toward rice cultivars.     

Myocardial Chemokine Expression and Intensity of Myocarditis in Chagas Cardiomyopathy Are Controlled by Polymorphisms in CXCL9 and CXCL10

Background

Chronic Chagas cardiomyopathy (CCC), a life-threatening inflammatory dilated cardiomyopathy, affects 30% of the approximately 8 million patients infected by Trypanosoma cruzi. Even though the Th1 T cell-rich myocarditis plays a pivotal role in CCC pathogenesis, little is known about the factors controlling inflammatory cell migration to CCC myocardium.

Methods and Results

Using confocal immunofluorescence and quantitative PCR, we studied cell surface staining and gene expression of the CXCR3, CCR4, CCR5, CCR7, CCR8 receptors and their chemokine ligands in myocardial samples from end-stage CCC patients. CCR5+, CXCR3+, CCR4+, CCL5+ and CXCL9+ mononuclear cells were observed in CCC myocardium. mRNA expression of the chemokines CCL5, CXCL9, CXCL10, CCL17, CCL19 and their receptors was upregulated in CCC myocardium. CXCL9 mRNA expression directly correlated with the intensity of myocarditis, as well as with mRNA expression of CXCR3, CCR4, CCR5, CCR7, CCR8 and their ligands. We also analyzed single-nucleotide polymorphisms for genes encoding the most highly expressed chemokines and receptors in a cohort of Chagas disease patients. CCC patients with ventricular dysfunction displayed reduced genotypic frequencies of CXCL9 rs10336 CC, CXCL10 rs3921 GG, and increased CCR5 rs1799988CC as compared to those without dysfunction. Significantly, myocardial samples from CCC patients carrying the CXCL9/CXCL10 genotypes associated to a lower risk displayed a 2–6 fold reduction in mRNA expression of CXCL9, CXCL10, and other chemokines and receptors, along with reduced intensity of myocarditis, as compared to those with other CXCL9/CXCL10 genotypes.

Conclusions

Results may indicate that genotypes associated to reduced risk in closely linked CXCL9 and CXCL10 genes may modulate local expression of the chemokines themselves, and simultaneously affect myocardial expression of other key chemokines as well as intensity of myocarditis. Taken together our results may suggest that CXCL9 and CXCL10 are master regulators of myocardial inflammatory cell migration, perhaps affecting clinical progression to the life-threatening form of CCC.     

Human chromosomes 9, 12, and 15 contain the nucleation sites of stress-induced nuclear bodies

We previously reported the identification of a novel nuclear compartment detectable in heat-shocked HeLa cells that we termed stress-induced Src-activated during mitosis nuclear body (SNB). This structure is the recruitment center for heat shock factor 1 and for a number of RNA processing factors, among a subset of Serine-Arginine splicing factors. In this article, we show that stress-induced SNBs are detectable in human but not in hamster cells. By means of hamster>human cell hybrids, we have identified three human chromosomes (9, 12, and 15) that are individually able to direct the formation of stress bodies in hamster cells. Similarly to stress-induced SNB, these bodies are sites of accumulation of hnRNP A1-interacting protein and heat shock factor 1, are usually associated to nucleoli, and consist of clusters of perichromatin granules. We show that the p13-q13 region of human chromosome 9 is sufficient to direct the formation of stress bodies in hamster>human cell hybrids. Fluorescence in situ hybridization experiments demonstrate that the pericentromeric heterochromatic q12 band of chromosome 9 and the centromeric regions of chromosomes 12 and 15 colocalize with stress-induced SNBs in human cells. Our data indicate that human chromosomes 9, 12, and 15 contain the nucleation sites of stress bodies in heat-shocked HeLa cells.     

Simulation of diffusion time of small molecules in protein crystals

A simple model for evaluation of diffusion times of small molecule into protein crystals has been developed, which takes into account the physical and chemical properties both of protein crystal and the diffusing molecules. The model also includes consideration of binding and the binding affinity of a ligand to the protein. The model has been validated by simulation of experimental set-ups of several examples found in the literature. These experiments cover a wide range of situations: from small to relatively large diffusing molecules, crystals having low, medium, or high protein density, and different size. The reproduced experiments include ligand exchange in protein crystals by soaking techniques. Despite the simplifying assumptions of the model, theoretical and experimental data are in agreement with available data, with experimental diffusion times ranging from a few seconds to several hours. The method has been used successfully for planning intermediate cryotrapping experiments in maltodextrin phosphorylase crystals.