Nanoparticulate architecture of protein-based artificial viruses is supported by protein-DNA interactions

AIM & METHODS: We have produced two chimerical peptides of 10.2 kDa, each contain four biologically active domains, which act as building blocks of protein-based nonviral vehicles for gene therapy. In solution, these peptides tend to aggregate as amorphous clusters of more than 1000 nm, while the presence of DNA promotes their architectonic reorganization as mechanically stable nanometric spherical entities of approximately 80 nm that penetrate mammalian cells through arginine-glycine-aspartic acid cell-binding domains and promote significant transgene expression levels. RESULTS & CONCLUSION: The structural analysis of the protein in these hybrid nanoparticles indicates a molecular conformation with predominance of α-helix and the absence of cross-molecular, β-sheet-supported protein interactions. The nanoscale organizing forces generated by DNA-protein interactions can then be observed as a potentially tunable, critical factor in the design of protein-only based artificial viruses for gene therapy.     

Psychometric properties and validity of short forms of the Wisconsin Schizotypy Scales in two large samples

The Wisconsin Schizotypy Scales (WSS) have been widely used in the study of clinical and non-clinical samples. However, researchers often find the length of the scales prohibitive. The present study examined the reliability and validity of recently developed 15-item short forms of the Perceptual Aberration, Magical Ideation, Physical Anhedonia, and Revised Social Anhedonia Scales in two large samples of non-clinically ascertained young adults. The scales demonstrated good reliability and correlated highly with the original scales. The validity of the scales was assessed by comparing the association of the original and shortened WSS with interview measures of psychotic-like and schizophrenia-spectrum symptoms and impaired functioning, as well as with questionnaire measures of personality and social impairment. The associations of the shortened WSS with the interview and questionnaire measures were comparable in terms of statistical significance and effect size with the associations of the original scales. The present findings provide the first demonstration of the validity of the shortened WSS and support their use in the study of schizotypy.     

Intra-specific variation in nitrate tolerance in tadpoles of the Natterjack toad

Anthropogenic sources of nitrogen that pollute bodies of water can have toxic and sub-lethal effects on amphibians. It has been hypothesized that such exposure may promote local adaptation, that is, selection for higher tolerance in individuals in populations exposed to pollutants. We tested this hypothesis with respect to the Natterjack toad (Bufo calamita Laurenti, 1768), by comparing the nitrate dose response of tadpoles from eight populations (doses: 0, 50, 100, 500 and 1000 mg/l nitrate) from relatively unpolluted and intensively farmed environments. We evaluated the effect of nitrate exposure by observing the behavior (movements) of tadpoles exposed to different concentrations of nitrates. Exposure to high nitrate levels did not cause tadpole mortality in the populations used in our experiments; however, we did observe changes in activity for all populations, with these changes being either dose-related responses (decreased activity after exposure to 500 or 1000 mg/l), or more complex responses (increased activity when exposed to 50 or 100 mg/l nitrate, followed by decreased activity at higher concentrations). Natterjack toad tadpoles exhibited variable behavioural responses among the tested populations. Although these populations were selected on the basis of their potential agrochemical contamination, the observed variation in population tolerance was not related to the parameters used to estimate this contamination in these breeding sites. Possible explanations for this apparent lack of local adaptation in B. calamita tadpoles include inadequate estimates of the toads’ actual nitrate exposure in the field, and the biological characteristics of B. calamita, which may limit the effects of exposure or favor phenotypic plasticity.     

Interstitial 13q14 deletions detected in the karyotype and translocations with concomitant deletion at 13q14 in chronic lymphocytic leukemia: Different genetic mechanisms but equivalent poorer clinical outcome

Deletion of 13q14 as the sole abnormality is a good prognostic marker in chronic lymphocytic leukemia (CLL). Nonetheless, the prognostic value of reciprocal 13q14 translocations [t(13q)] with related 13q losses has not been fully elucidated. We described clinical and biological characteristics of 25 CLL patients with t(13q), and compared with 62 patients carrying interstitial del(13q) by conventional G‐banding cytogenetics (CGC) [i‐del(13q)] and 295 patients with del(13q) only detected by fluorescence in situ hybridization (FISH) [F‐del(13q)]. Besides from the CLL FISH panel (D13S319, CEP12, ATM, TP53), we studied RB1 deletions in all t(13q) cases and a representative group of i‐del(13q) and F‐del(13q). We analyzed NOTCH1, SF3B1, and MYD88 mutations in t(13q) cases by Sanger sequencing. In all, 25 distinct t(13q) were described. All these cases showed D13S319 deletion while 32% also lost RB1. The median percentage of 13q‐deleted nuclei did not differ from i‐del(13q) patients (73% vs. 64%), but both were significantly higher than F‐del(13q) (52%, P < 0.001). Moreover, t(13q) patients showed an increased incidence of biallelic del(13q) (52% vs. 11.3% and 14.9%, P < 0.001) and higher rates of concomitant 17p deletion (37.5% vs. 8.6% and 7.2%, P < 0.001). RB1 involvement was significantly higher in the i‐del(13q) group (79%, P < 0.001). Two t(13q) patients (11.8%) carried NOTCH1 mutations. Time to first treatment in t(13q) and i‐del(13q) was shorter than F‐del(13q) (67, 44, and 137 months, P = 0.029), and preserved significance in the multivariate analysis. In conclusion, t(13q) and del(13q) patients detected by CGC constitute a subgroup within the 13q‐deleted CLL patients associated with a worse clinical outcome. © 2014 Wiley Periodicals, Inc.     

Influenza C virus surveillance during the first influenza A (H1N1) 2009 pandemic wave in Catalonia, Spain

Although particular attention is paid to influenza A and B virus isolates during influenza surveillance, influenza C virus (FLUCV) coexisted during the first influenza A (H1N1) 2009 pandemic wave during the 2009-2010 season. From 27 April 2009 to 9 May 2010, 12 strains of FLUCV were detected in specimens collected from 1713 nonhospitalized patients with upper respiratory tract illness using a molecular method. Half of the patients with FLUCV infection were older than 14 years. The most frequent symptoms were cough and fever, similar to other viral respiratory infections. Phylogenetic analysis of the hemagglutinin-esterase gene revealed that the strains belonged to the C/Kanagawa/1/76-related and C/Sao Paulo/378/82-related lineages, demonstrating their co-circulation in Catalonia. In addition to regular virological surveillance that provides information about the incidence and the exact role of FLUCV in acute viral respiratory infections in the general population, the genetic lineage identification offers additional data for epidemiological purposes.     

Systemic sclerosis fibroblasts inhibit in vitro angiogenesis by MMP-12-dependent cleavage of the endothelial cell urokinase receptor

Failure of endothelial cells to develop new vessels in response to hypoxia is a distinctive feature of systemic sclerosis (SSc) in the avascular phase. We have previously shown that SSc endothelial cells over-express matrix metalloproteinase-12 (MMP-12), which blocks angiogenesis by cleavage of the endothelial urokinase-type plasminogen activator receptor (uPAR). In the present study, we have investigated whether over-expression of MMP-12 and of angiostatic factors, or hypo-expression of angiogenic factors by SSc fibroblasts, contributes to impaired angiogenesis in SSc. Dermal fibroblasts were isolated from healthy subjects (N-Fb) and patients with diffuse SSc (SSc-Fb). Angiogenesis of target normal human microvascular endothelial cells (H-MVECs) was assayed by Matrigel invasion, cell proliferation, and capillary morphogenesis. uPAR cleavage and MMP-12 activity were evaluated by western blotting. We show that the over-expression of MMP-12 by SSc-Fb determines uPAR cleavage in H-MVECs. Conditioned medium from SSc-Fb impaired H-MVEC proliferation, invasion, and capillary morphogenesis. Anti-MMP-12 antibodies restored such impairment. Altered expression of angiostatic/angiogenic factors, including transforming growth factor beta1, did not account for SSc-Fb-dependent impairment of angiogenesis. The over-expression of MMP-12 by both SSc-Fb and SSc endothelial cells indicates that MMP-12 over-production may have a critical pathogenic role in SSc-associated vascular alterations.