Stocking density at early developmental stages affects growth and sex ratio in the European eel (Anguilla anguilla)

To investigate the effect of stocking density on growth and sex ratio in European eel, four constant density conditions were tested during the transition from the glass to the elver stage for 90 days (Period 1). The test conditions combined the weight of fish per unit surface or volume (surface density or volume density) resulting in four experimental groups: low surface density (0.5 kg/m(2)) and low volume density (5 kg/m(3)) (group S(0.5)V(5)); low surface density (0.5 kg/m(2)) and high volume density (10 kg/m(3)) (group S(0.5)V(10)); high surface density (2 kg/m(2)) and low volume density (5 kg/m(3)) (group S(2)V(5)); and high surface density (2 kg/m(2)) and high volume density (10 Kg/m(3)) (group S(2)V(10)). Subsequently, fish from the S(0.5)V(5), S(2)V(5), and S(2)V(10) groups were transferred to low density conditions (0.1-0.4 kg/m(2) or 0.1-0.3 kg/m(3)) for another 21 months (630 days; Period 2). After Period 1, fish maintained at high surface density, regardless of the volume density, showed higher standard growth rates (SGRs) and RNA/DNA ratio in muscle than those cultured at low surface density. The percentage of mortality was similar in three of the groups (34.2%-41.8%), but not in the S(2)V(10) group (83.3%). At the end of Period 2, most fish (about 95%) exhibited fully differentiated gonads, but different sex ratios were observed in each group. Thus, the S(2)V(5) group showed a higher proportion of females (36.1%) and a lower proportion of males (56.8%) than the S(0.5)V(5) group (11.4% and 72.5%, respectively), while all survivor fish from the S(2)V(10) group developed into females. The gonadosomatic index and SGR were higher in females than in males. These results suggest that glass eels maintained at high surface density during the first months of growth tend to develop into females. The data also indicate that growth and sex ratio are linked processes during eel development, with growth seeming to be sex dependant rather than being influenced by the density conditions in which glass eels are maintained.     

The endoplasmic reticulum is a key component of the plasma cell death pathway

Plasma cells (PC) are the effector cells of the humoral Ab response. Unlike other dedicated secretory cells, they exist as two populations with opposite cell fates: short-lived and long-lived PC. Upon transformation they lead to an incurable neoplasia called multiple myeloma. In this study we have explored the molecular mechanism of PC death. Our data show that their apoptotic pathway is unique among other hemopoietic cells inasmuch as neither the death receptors nor the mitochondria play the central role. PC apoptosis is initiated by activation of Bax at the endoplasmic reticulum membrane and subsequent activation of the endoplasmic reticulum-associated caspase-4 before the release of mitochondrial apoptogenic factors. Together, our observations indicate that the cardinal function of PC (i.e., Ig secretion) is also the cause of their death.     

Bim-dependent apoptosis follows IGFBP-5 down-regulation in neuroblastoma cells

The insulin-like growth factor (IGF) axis is frequently activated in neuroblastoma (NB) tumors and cell lines. We show that silencing endogenous expression of IGF Binding Protein-5 (IGFBP-5) in NB cells by using microRNA and siRNA causes mitochondrial apoptosis that is characterized by: (a) release of cytochrome C in the cytoplasm and activation of caspase 9; (b) Erk1 and Erk2 inhibition; and (c) upregulation of pro-apoptotic proteins Bim and Bax. Bim upregulation is caused, at least in part, by protein stabilization that may depend on inhibition of Erk1 and Erk2. Of interest, Bim knock-down by siRNA decreases apoptosis in IGFBP-5-interfered cells. Thus, inhibition of endogenously produced IGFBP-5 is associated with Bim-dependent apoptosis in NB cells.     

Evolutionary history of the Tricladida and the Platyhelminthes: an up-to-date phylogenetic and systematic account

Within the free-living platyhelminths, the triclads, or planarians, are the best-known group, largely as a result of long-standing and intensive research on regeneration, pattern formation and Hox gene expression. However, the group's evolutionary history has been long debated, with controversies ranging from their phyletic structure and position within the Metazoa to the relationships among species within the Tricladida. Over the the last decade, with the advent of molecular phylogenies, some of these issues have begun to be resolved. Here, we present an up-to-date summary of the main phylogenetic changes and novelties with some comments on their evolutionary implications. The phylum has been split into two groups, and the position of the main group (the Rhabdithophora and the Catenulida), close to the Annelida and the Mollusca within the Lophotrochozoa, is now clear. Their internal relationships, although not totally resolved, have been clarified. Tricladida systematics has also experienced a revolution since the implementation of molecular data. The terrestrial planarians have been demonstrated to have emerged from one of the freshwater families, giving a different view of their evolution and greatly altering their classification. The use of molecular data is also facilitating the identification of Tricladida species by DNA barcoding, allowing better knowledge of their distribution and genetic diversity. Finally, molecular phylogenetic and phylogeographical analyses, taking advantage of recent data, are beginning to give a clear picture of the recent history of the Dugesia and Schmidtea species in the Mediterranean.     

Assessment of microbial quality of commercial and home-made tiger-nut beverages

Aims: We aimed to assess the microbiological quality of Spanish commercial tiger‐nut beverages as well as home‐made samples collected from supermarkets, street vendors, juice bars and ice‐cream parlours located in Valencia. Methods and Results: Microbiological analysis of 44 tiger‐nut beverages samples were carried out according to International Standard Organization (ISO) norms and published works which included the total viable count, Enterobacteriaceae, Escherichia coli, Staphylococcus aureus, Salmonella, Bacillus cereus, yeasts, moulds, Yersinia enterocolitca, Clostridium perfringens, Vibrio spp. and Listeria monocytogenes. The obtained results indicated that all the commercial samples were below the detection limit for the viable microorganisms. Results of analysis of those home‐made tiger‐nut samples revealed that 67% (16 samples) harboured total plate counts while the rest of samples were free from these microorganisms. Enterobacteriaceae were detected in 62% (15 samples). E. coli were found in only one sample (4%), yeasts and moulds were detected in 62% (15 samples) each, Shigella was found in 21% (five samples); however, all samples were free from S. aureus, Salmonella, Y. enterocolotica, C. perfringens, Vibrio spp. and L. monocytogenes. Conclusions: These results reflected that there exists a rather high contamination level in home‐made tiger‐nut beverages indicating the need to apply correct and strict HACCP system(s) during manufacturing and storage of these food products. Significance and Impact of Study: This study demonstrates the great need to carry out microbiological tests frequently in these products and even more the need to apply correct HACCP system (s). Tiger‐nut beverages are especially well‐known products in Spain, hence it is extremely important to ensure an adequate microbiological quality to guarantee consumers health.     

A stable panel comprising 18 urinary proteins in the human healthy population

Just as biomarkers specific for diseases, biomarkers indicative of healthy conditions are valuable for the early diagnosis, monitoring, and prognosis of diseases. Our study focused on discovering via proteomics a stable panel of urinary proteins in the human healthy population. Urine samples were collected three times during 4 months from 100 male and 100 female healthy donors and analyzed through four different fractionation techniques (i.e. in-gel, 2D-LC, OFFGEL, and mRP) coupled with HPLC-Chip-MS/MS. Thus, 1641 urinary proteins were identified with a high confidence, among which 70 exhibiting an intergender/day variation <0.25 were selected and matched with the previously published five largest urinary proteomes to get 56 candidate proteins. Next, a panel comprising 18 intact urinary proteins was constructed by comparing the urinary proteomes via SDS-PAGE and 2DE. Finally, such 18 urinary proteins were validated via enzyme-linked immunosorbent assay in eight healthy individuals. Most of these proteins had been related to multiple rather than to single diseases. Therefore, we surmise that this protein set could be used as a biomarker to assess the human health status. Further determinations of the normal fluctuations of the single urinary proteins in this series using samples from large numbers of healthy individuals are required prior to any application in clinical settings.     

MTOR regulates autophagic flux in the glomerulus

Sirolimus (rapamycin), an inhibitor of the mechanistic target of rapamycin (MTOR), was originally proposed as an immunosuppressant to prevent rejection of solid organ transplants. There were expectations that MTOR inhibitors would replace nephrotoxic calcineurin inhibitors (CNIs). Despite its potential advantages, evidence that sirolimus causes de novo or worsening proteinuria is unequivocal. Given the well-recognized proteinuric effect of MTOR inhibitors, we were interested in understanding its role in maintaining the glomerular filtration barrier. To investigate this in vivo, we developed a mouse model with a podocyte selective deletion of the Mtor gene (Mtor pod-KO).