Single-molecule analysis reveals cooperative stimulation of Rad51 filament nucleation and growth by mediator proteins

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On the occurrence of the fireworm Eurythoe?complanata complex (Annelida,Amphinomidae) in the Mediterranean Sea with an updated revision of the alien Mediterranean amphinomids

The presence of two species within the Eurythoe complanata complex in the Mediterranean Sea is reported, as well as their geographical distributions. One species, Eurythoe laevisetis, occurs in the eastern and central Mediterranean, likely constituting the first historical introduction to the Mediterranean Sea and the other, Eurythoe complanata, in both eastern and Levantine basins. Brief notes on their taxonomy are also provided and their potential pathways for introduction to the Mediterranean are discussed. A simplified key to the Mediterranean amphinomid genera and species of Eurythoe and Linopherus is presented plus an updated revision of the alien amphinomid species reported previously from the Mediterranean Sea. A total of five exotic species have been included; information on their location, habitat, date of introduction and other relevant features is also provided.     

Safety Evaluation of Lactobacillus delbrueckii subsp. lactis CIDCA 133: a Health-Promoting Bacteria

Probiotics and Antimicrobial Proteins - Lactobacillus delbrueckii subsp. lactis CIDCA is a new potential probiotic strain whose molecular basis attributed to the host’s benefit has been...     

The Ribosome Biogenesis Protein Nol9 Is Essential for Definitive Hematopoiesis and Pancreas Morphogenesis in Zebrafish

Ribosome biogenesis is a ubiquitous and essential process in cells. Defects in ribosome biogenesis and function result in a group of human disorders, collectively known as ribosomopathies. In this study, we describe a zebrafish mutant with a loss-of-function mutation in nol9, a gene that encodes a non-ribosomal protein involved in rRNA processing. nol9 ^{sa1022/sa1022} mutants have a defect in 28S rRNA processing. The nol9 ^{sa1022/sa1022} larvae display hypoplastic pancreas, liver and intestine and have decreased numbers of hematopoietic stem and progenitor cells (HSPCs), as well as definitive erythrocytes and lymphocytes. In addition, ultrastructural analysis revealed signs of pathological processes occurring in endothelial cells of the caudal vein, emphasizing the complexity of the phenotype observed in nol9 ^{sa1022/sa1022} larvae. We further show that both the pancreatic and hematopoietic deficiencies in nol9 ^{sa1022/sa1022} embryos were due to impaired cell proliferation of respective progenitor cells. Interestingly, genetic loss of Tp53 rescued the HSPCs but not the pancreatic defects. In contrast, activation of mRNA translation via the mTOR pathway by L-Leucine treatment did not revert the erythroid or pancreatic defects. Together, we present the nol9 ^{sa1022/sa1022} mutant, a novel zebrafish ribosomopathy model, which recapitulates key human disease characteristics. The use of this genetically tractable model will enhance our understanding of the tissue-specific mechanisms following impaired ribosome biogenesis in the context of an intact vertebrate.     

Effect of Moringa oleifera flower extract on larval trypsin and acetylcholinesterase activities in Aedes aegypti

Aedes aegypti control is crucial to reducing dengue fever. Aedes aegypti larvae have developed resistance to organophosporous insecticides and the use of natural larvicides may help manage larval resistance by increasing elements in insecticide rotation programs. Here, we report on larvicidal activity of Moringa oleifera flower extract against A. aegypti L(1), L(2), L(3), and L(4) as well as the effect of flower extract on gut trypsin and whole-larval acetylcholinesterase from L(4.) In addition, the heated flower extract was investigated for larvicidal activity against L(4) and effect on larval gut trypsin. Moringa oleifera flower extract contains a proteinaceous trypsin inhibitor (M. oleifera flower trypsin inhibitor, MoFTI), triterpene (β-amyrin), sterol (β-sitosterol) as well as flavonoids (kaempferol and quercetin). Larvicidal activity was detected against L(2), L(3), and L(4) (LC(50) of 1.72%, 1.67%, and 0.92%, respectively). Flower extract inhibited L(4) gut trypsin (MoFTI K(i) = 0.6 nM) and did not affect acetylcholinesterase activity. In vivo assay showed that gut trypsin activity from L(4) treated with M. oleifera flower extract decreased over time (0-1,440 min) and was strongly inhibited (98.6%) after 310 min incubation; acetylcholinesterase activity was not affected. Thermal treatment resulted in a loss of trypsin inhibitor and larvicidal activities, supporting the hypothesis that flower extract contains a proteinaceous trypsin inhibitor that may be responsible for the deleterious effects on larval mortality.     

Evaluating HapMap SNP data transferability in a large-scale genotyping project involving 175 cancer-associated genes

One of the many potential uses of the HapMap project is its application to the investigation of complex disease aetiology among a wide range of populations. This study aims to assess the transferability of HapMap SNP data to the Spanish population in the context of cancer research. We have carried out a genotyping study in Spanish subjects involving 175 candidate cancer genes using an indirect gene-based approach and compared results with those for HapMap CEU subjects. Allele frequencies were very consistent between the two samples, with a high positive correlation (R) of 0.91 (P<<1×10⁻⁶). Linkage disequilibrium patterns and block structures across each gene were also very similar, with disequilibrium coefficient (r ²) highly correlated (R=0.95, P<<1×10⁻⁶). We found that of the 21 genes that contained at least one block larger than 60 kb, nine (ATM, ATR, BRCA1, ERCC6, FANCC, RAD17, RAD50, RAD54B and XRCC4) belonged to the GO category “DNA repair”. Haplotype frequencies per gene were also highly correlated (mean R=0.93), as was haplotype diversity (R=0.91, P<<1×10⁻⁶). “Yin yang” haplotypes were observed for 43% of the genes analysed and 18% of those were identical to the ancestral haplotype (identified in Chimpazee). Finally, the portability of tagSNPs identified in the HapMap CEU data using pairwise r ² thresholds of 0.8 and 0.5 was assessed by applying these to the Spanish and current HapMap data for 66 genes. In general, the HapMap tagSNPs performed very well. Our results show generally high concordance with HapMap data in allele frequencies and haplotype distributions and confirm the applicability of HapMap SNP data to the study of complex diseases among the Spanish population. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.     

Assessment of digenean parasitism in Nassarius reticulatus (L.) along the Portuguese coast: evaluation of possible impacts on reproduction and imposex expression

A survey was performed between June and September 2006 along the Portuguese coast to assess the prevalence of digenean parasitism in the netted whelk Nassarius reticulatus, a bioindicator of tributyltin (TBT) pollution. It was also intended to evaluate the effect of parasites on the reproduction of this gastropod species and their interference on the development of imposex (the superimposition of male characters onto prosobranch females) and male penis, based on field data. Five digenean species (Lepocreadium album, Gynaecotyla longiintestinata, Himasthla quissetensis, Diphtherostomum brusinae, and Cardiocephalus longicollis), plus 1 unidentified species, were found to infect N. reticulatus. Parasitism was spread along the Portuguese coast, but the higher values of prevalence were found in sheltered inshore areas where up to 67.4% of the animals were affected per sampling station. Parasitism has a castrating impact on the whelks and a reducing effect on male penis size, which causes serious disorders in the reproduction of N. reticulatus and may have an important impact in its population dynamics. However, no relationship between imposex severity and parasite infestation was found.     

Lipid bilayer pre-transition as the beginning of the melting process

We investigate the bilayer pre-transition exhibited by some lipids at temperatures below their main phase transition, and which is generally associated to the formation of periodic ripples in the membrane. Experimentally we focus on the anionic lipid dipalmytoylphosphatidylglycerol (DPPG) at different ionic strengths, and on the neutral lipid dipalmytoylphosphatidylcholine (DPPC). From the analysis of differential scanning calorimetry traces of the two lipids we find that both pre- and main transitions are part of the same melting process. Electron spin resonance of spin labels and excitation generalized polarization of Laurdan reveal the coexistence of gel and fluid domains at temperatures between the pre- and main transitions of both lipids, reinforcing the first finding. Also, the melting process of DPPG at low ionic strength is found to be less cooperative than that of DPPC. From the theoretical side, we introduce a statistical model in which a next-nearest-neighbor competing interaction is added to the usual two-state model. For the first time, modulated phases (ordered and disordered lipids periodically aligned) emerge between the gel and fluid phases as a natural consequence of the competition between lipid-lipid interactions.     

Biotransformation of menthol and geraniol by hairy root cultures of <Emphasis Type="Italic">Anethum graveolens</Emphasis>: effect on growth and volatile components

Two oxygen-containing monoterpene substrates, menthol or geraniol (25 mg l⁻¹), were added to Anethum graveolens hairy root cultures to evaluate the influence of the biotransformation capacity on growth and production of volatile compounds. Growth was assessed by the dissimilation method and by fresh and dry weight measurement. The volatiles were analyzed by GC and GC–MS. The total constitutive volatile component was composed, in more than 50%, by falcarinol (17–52%), apiole (11–24%), palmitic acid (7–16%), linoleic acid (4–9%), myristicin (4-8%) and n-octanal (2-5%). Substrate addition had no negative influence on growth. The relative amount of menthol quickly decreased 48 h after addition, and the biotransformation product menthyl acetate was concomitantly formed. Likewise, the added geraniol quickly decreased over 48 h alongside with the production of the biotransformation products. The added geraniol was biotransformed in 10 new products, the alcohols linalool, α-terpineol and citronellol, the aldehydes neral and geranial, the esters citronellyl, neryl and geranyl acetates and linalool and nerol oxides. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Clinical delineation of a patient with trisomy 1q32.qter and monosomy 5p resulting from a familial translocation 1;5

We describe a patient who had multiple malformations including ventriculomegaly, colpocephaly, corpus callosum, cerebellum and vermix hypoplasia, optic nerve hypoplasia, corneal opacity and congenital heart disease in whom a trisomy 1q32-qter and monosomy 5p derived from a t(1;5)mat was diagnosed by karyotype and FISH analysis. This trisomy/monosomy association has not been previously reported. The familial analysis of the translocation was carried out in four generations and its implications on the phenotype of the patient and genetic counseling are discussed.