A single amino acid substitution in the novel H7N9 influenza A virus NS1 protein increases CPSF30 binding and virulence

Although an effective interferon antagonist in human and avian cells, the novel H7N9 influenza virus NS1 protein is defective at inhibiting CPSF30. An I106M substitution in H7N9 NS1 can restore CPSF30 binding together with the ability to block host gene expression. Furthermore, a recombinant virus expressing H7N9 NS1-I106M replicates to higher titers in vivo, and is subtly more virulent, than parental. Natural polymorphisms in H7N9 NS1 that enhance CPSF30 binding may be cause for concern

Pediatric ocular rosacea, a misdiagnosed disease with high morbidity: Proposed diagnostic criteria

Ocular rosacea is an important and underdiagnosed chronic inflammatory disorder observed in children. A clinical spectrum ranging from chronic eyelid inflammation, recurrent ocular redness, photophobia and/or hordeola/chalazions and conjunctival/corneal phlyctenules evolving to neovascularization and scarring may occur. Visual impairment and consequent amblyopia are frequent and corneal perforation although rare is the most feared complication. Ocular manifestations usually precede cutaneous lesions. Although few cases of pediatric ocular rosacea (POR) have been reported in the literature, many cases must have been underdiagnosed or misdiagnosed. The delay in diagnosis is greater than one year in the large majority of cases and may lead to serious ocular sequelae. This review aims to highlight the clinical features of POR, its epidemiology, easy diagnosis and effective treatment. We also propose new diagnostic criteria, in which at least three of the five clinical criteria must be present: (1) Chronic or recurrent keratoconjunctivitis and/or red eye and/or photophobia; (2) Chronic or recurrent blepharitis and/or chalazia/ hordeola; (3) Eyelid telangiectasia documented by an ophthalmologist; (4) Primary periorificial dermatitis and/ or primary features of rosacea; and (5) Positive familial history of cutaneous and/or ocular rosacea

Diversification processes between monogenoids (Dactylogyridae) and their marine catfish (Siluriformes: Ariidae) from the Atlantic coast of South America

Due to their high specificity, monogenoids from fish provide an interesting model to study historical associations of hosts and parasites. High agreement between host and parasite phylogeny is often interpreted as evidence of cospeciation. However, cophylogenetic signal may also arise from other, either adaptive or non-adaptive, processes. We applied the recently developed Cophylospace Framework to better understand the evolutionary relationship between monogenoids and marine catfish from the Atlantic coast of South America. The associations between 12 marine catfish and 10 monogenoid species were assessed. Molecular data of host and parasite species were used for phylogenetic reconstruction. We used anchor morphology based on Procrustes coordinates to evaluate whether closely related hosts are associated with morphologically similar parasites. To assess the association between parasite phylogeny and host morphology, we produced a distance matrix based on morphological characters of catfishes. Agreement between phylogenies and between phylogeny and morphology was measured using Procrustes R2 computed with PACo. The parasite phylogeny obtained in this study represents the first complete phylogenetic hypothesis of monogenoids parasitizing ariids from South America. The Cophylospace analysis suggested that phylogenetic and morphological distance of monogenoids contributes similarly to explain the pattern of host-parasite associations, whereas parasite phylogeny is more strongly associated with the morphological traits of the hosts than with host phylogeny. This evidence suggests that cospeciation is not a major force accounting for diversification in the monogenoids studied. Rather host morphological traits seem to be a more important driver, which conforms with evidence from other host‒monogenoid systems

An overview

Human diseases caused by protozoan parasites are renowned for their high rates of morbidity and mortality worldwide. Some examples include African trypanosomiasis or sleeping sickness, American trypanosomiasis or Chagas disease, leishmaniases, malaria and babesiosis. These infections tend to follow a chronic rather than an acute course with lifelong persistence of parasites. Regulatory T cells (Treg), in particular the CD4+CD25+ cell subset, appear to control the immune competence of host response triggered by the presence of parasites, promoting homeostasis and protecting the host from collateral tissue damage whilst allowing parasite persistence. To date, there is still considerable controversy on the characteristics and function of these cells when induced during diferente protozoan infections, evidencing the need of further research. Therefore, this review aims to provide a comprehensive overview about Treg cells development, phenotype determination and general functions. The above pathologies were used as selected examples to discuss the role of Treg cells during protozoan infections. Understanding of the mechanisms that contribute towards homeostasis and the survival of the host, and simultaneously allow the persistence of the pathogen, may yield important insights for new strategies of prophylaxis and therapy .publishersversionpublishe

Biotechnological versatility of riboflavin producer Ashbya gossypii Expression of Trichoderma reesei cellulases CBHI and EGI

The filamentous fungus Ashbya gossypii shows the potential for the production of, yet unexploited, valuable compounds other than riboflavin. To explore the ability of A. gossypii as a host for the expression of recombinant proteins, endoglucanase I (EGI) and cellobiohydrolase I (CBHI) from the fungus Trichoderma reesei were expressed in A. gossypii under Saccharomyces cerevisiae PGK1 promoter. The proteins were secreted into the culture medium, but there were differences in the amount or activity of the protein being produced. In one hand, CBHI activity was not detected using 4-methylumbelliferyl--Dlactoside as substrate, being only detected by Western blot. On the other hand, EGI activity was detectable, the level of activity being comparable to that produced by a S. cerevisiae strain containing the same plasmid. Thus more EGI was secreted than CBHI, or more active protein was produced. Partial characterization of CBHI and EGI expressed in A. gossypii revealed overglycosylation when compared to the native T. reesei proteins, but the glycosylation was less extensive than on cellulases expressed in S. cerevisiae

Experimental evaluation of an innovative command for hydronic radiant heating floors

This paper presents the results of an innovative control, regulation and command system for hydronic radiant floors, more flexible and efficient that guarantees a better thermal comfort to the user and simultaneously improves the energy efficiency of this type of heating system. The control algorithm is based on the calculation of PMV (Predicted Mean Vote) index as defined on Thermal Comfort Standard ISO 7730. To improve energy efficiency, the control algorithm was implemented on a microcontroller system that fea-tures wireless communication with sensors modules powered by energy harvesting systems. The experimental tests were performed in a hydraulic underfloor built into a laboratorial climatic chamber. The results show that for a water inlet of 35 ºC, the controller turn the valve on/off less than other control systems in order to adjust the PMV while maintaining the floor surface temperature less than 29 ºC as recommended by international standards.info:eu-repo/semantics/publishedVersio

Evaluation of a novel fusion system for soluble protein overexpression in Escherichia coli

Proteins production requires a successful correlation between expression, solubility and purification steps. As an expression system, Escherichia coli combines its low cost and ease of use with rapid expression, being widely used for heterologous protein production. This host cell has however several drawbacks, namely at the expression of insoluble proteins aggregated into inclusion bodies. Many efforts have been made to overcome such problems, including the optimization of expression conditions and the use of solubility fusion tags. The use of fusion tags for protein production remains challenging since none of the available fusion systems work universally with every partner protein. A novel fusion system had been recently discovered and submitted to a patenting process by Hitag Biotechnology, Lda. This fusion system consists of low molecular weight peptides/proteins from recombinant antigens, which have demonstrated to increase soluble protein expression levels in E. coli. This work aims at the evaluation of the effects of two novel fusion tags on soluble protein expression in E. coli. Specific primers were designed to amplify and sub‐clone gene sequences that encodes for frutalin, Cryptosporidium parvum 12kDa protein and Giardia lamblia cyst wall protein. These target proteins present therapeutic and diagnostic interests and had shown to be difficult‐to‐express in E. coli. Proteins were first fused to novel tags and than expressed in E. coli. Proteins purification was carried out by affinity chromatography, using nickel‐NTA columns. Pooled fractions were dialysed against phosphate buffer pH 7.4 and latter analysed by SDS‐PAGE. Protein expression levels were determined by Bradford assay. When fused to novel tags, all target proteins were successfully expressed in E. coli. Comparing to the respective non‐fused proteins, both novel tags used in this work promoted an increase from three to nine folds on soluble proteins expression levels. The SDS‐PAGE analysis confirmed the purity of Ni‐NTA pooled fractions, corroborating also these results. Tag1‐fusions achieved higher production yields than fusions with Tag2. In this work, three different target proteins were used to evaluate two novel fusion tags. The soluble overexpression effect offered by this novel fusion system may provide an important advance in recombinant protein expression processes in E. coli

Metallurgical evaluation of laser sintered M3/2 HSS powder

Direct Metal Laser Sintering (DMLS) is one of the leading commercial rapid tooling (RT) technologies that produce 3D fully functional parts and tools directly from a CAD model. High Speed Steels (HSS) have the desired combination of hot hardness, wear resistance and toughness needed for applications such as cutting tools, special tools, inserts and dies that can be successfully developed in a near net shape by DMLS. This paper presents a study of DMLS of commercial water atomized M3/2 powder with different apparent densities. The effect of apparent density and DMLS process parameters on the surface morphologies and microstructure of laser sintered M3/2 powder was analysed and the optimum processing conditions to reduce balling effect were identified. Laser sintered M3/2 HSS with energy densities between 2.4 and 12 J/mm2 produced a coarse roughness (Rz) ranging from 135 to 234μm. The lowest roughness (65μm) was obtained with 36J/mm2, the highest laser energy density value used. The microstructure of laser sintered M3/2 HSS consisted of austenite, martensite and a fine carbide structure