AIP56, a novel plasmid-encoded virulence factor of Photobacterium damselae subsp. piscicida with apoptogenic activity against sea bass macrophages and neutrophils

A strategy used by extracellular pathogens to evade phagocytosis is the utilization of exotoxins that kill host phagocytes. We have recently shown that one major pathogenicity strategy of Photobacterium damselae subsp. piscicida (Phdp), the agent of the widespread fish pasteurellosis, is the induction of extensive apoptosis of sea bass macrophages and neutrophils that results in lysis of these phagocytes by post-apoptotic secondary necrosis. Here we show that this unique process is mediated by a novel plasmid-encoded apoptosis inducing protein of 56 kDa (AIP56), an exotoxin abundantly secreted by all virulent, but not avirulent, Phdp strains tested. AIP56 is related to an unknown protein of the enterohemorrhagic Escherichia coli O157:H7 and NleC, a Citrobacter rodentium type III secreted effector of unknown function. Passive immunization of sea bass with a rabbit anti-AIP56 serum conferred protection against Phdp challenge, indicating that AIP56 represents a key virulence factor of that pathogen and is a candidate for the design of an anti-pasteurellosis vaccine.     

Phase 1 trial of AMA1-C1/Alhydrogel plus CPG 7909: an asexual blood-stage vaccine for Plasmodium falciparum malaria

Background

Apical Membrane Antigen 1 (AMA1), a polymorphic merozoite surface protein, is a leading blood-stage malaria vaccine candidate. This is the first reported use in humans of an investigational vaccine, AMA1-C1/Alhydrogel, with the novel adjuvant CPG 7909.

Methods

A phase 1 trial was conducted at the University of Rochester with 75 malaria-naive volunteers to assess the safety and immunogenicity of the AMA1-C1/Alhydrogel+CPG 7909 malaria vaccine. Participants were sequentially enrolled and randomized within dose escalating cohorts to receive three vaccinations on days 0, 28 and 56 of either 20 µg of AMA1-C1/Alhydrogel®+564 µg CPG 7909 (n = 15), 80 µg of AMA1-C1/Alhydrogel® (n = 30), or 80 µg of AMA1-C1/Alhydrogel+564 µg CPG 7909 (n = 30).

Results

Local and systemic adverse events were significantly more likely to be of higher severity with the addition of CPG 7909. Anti-AMA1 immunoglobulin G (IgG) were detected by enzyme-linked immunosorbent assay (ELISA), and the immune sera of volunteers that received 20 µg or 80 µg of AMA1-C1/Alhydrogel+CPG 7909 had up to 14 fold significant increases in anti-AMA1 antibody concentration compared to 80 µg of AMA1-C1/Alhydrogel alone. The addition of CPG 7909 to the AMA1-C1/Alhydrogel vaccine in humans also elicited AMA1 specific immune IgG that significantly and dramatically increased the in vitro growth inhibition of homologous parasites to levels as high as 96% inhibition.

Conclusion/Significance

The safety profile of the AMA1-C1/Alhydrogel+CPG 7909 malaria vaccine is acceptable, given the significant increase in immunogenicity observed. Further clinical development is ongoing.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00344539","term_id":"NCT00344539"}}NCT00344539     

Temporoparietal fascial flap for orbital and eyelid reconstruction.

The temporoparietal fascial flap is a recognized technique for the transfer of vascularized tissue in the craniofacial region. The flap has a predictable axial vessel, provides thin vascularized tissue, and can be harvested with minimal donor-site morbidity. The temporoparietal fascial flap is well suited for orbital or eyelid reconstruction because of its proximity to the orbit. The flap is useful for reconstruction of anatomic barriers between the orbit, intracranial cavity, and paranasal sinus spaces. We present four patients in whom the temporoparietal fascial flap was used for orbital reconstruction following extirpative surgery for orbital neoplasm and two patients in whom the flap was used for lower eyelid and malar reconstruction.     

The active site of hemerythrin as determined by X-ray absorption fine structure

Extensive X-ray absorption fine structure measurements and analysis have been made on azidomet- and methemerythrin and on the native forms of oxy- and deoxyhemerythrin. Due to the availability of models that have been synthesized to mimic the active site of hemerythrin, it was possible to make a thorough assessment of the various errors in the structural parameters determined by the analysis. It is found that the largest source of error is the lack of complete transferability of amplitude and phase between the standards and hemerythrin. This is of particular importance in distinguishing the contributions of the second-shell low-Z atoms and, thus, has a substantial influence on the determination of the iron-iron distance. The internal consistencies of the various checks and a new formulation of error analysis for the structural parameters give us confidence in the structure determined for the active site. The main result is that as O2 is released from oxyhemerythrin, the mu-oxo bridge between the two iron atoms in the active site with an Fe-O distance of 1.8 A converts to a mu-hydroxo bridge in deoxyhemerythrin, expanding the Fe-O distance to 2.0 A. The Fe-Fe distance expands proportionally from 3.24 A in oxyhemerythrin to 3.57 A in deoxyhemerythrin so as to keep the Fe-O-Fe bridging angle approximately constant. These conclusions provide experimental support for the structures of oxy- and deoxyhemerythrin proposed previously on the basis of spectroscopic and preliminary X-ray crystallographic data.     

A role for artificial night-time lighting in long-term changes in populations of 100 widespread macro-moths in UK and Ireland: a citizen-science study

The abundance of 100 of the most widespread species of macro-moth in the UK and Ireland was estimated from light-trap records reported to the UK and Ireland Garden Moth Scheme between 2005 and 2015. Recording sites were classified into low, medium and high night-time illumination categories by satellite imagery, into land-use types from the dominant use in the 1–2 km surrounding area, and by latitude. Most urban sites were in the group classified as having high night-time illumination. Comparison between medium and low night-time illuminated sites allowed differences between levels of illumination free from the effect of urbanization on moth abundance to be assessed. The medium and low night-time illuminated sites differed significantly in the frequency of grassland and arable land-use types and in geographic location with more grassland and north-western sites in the low-light category. After adjustment for these differences and for variations between taxonomic family groups, the medium to low night-time lighting abundance ratios explained a significant (P?<?0.001) 20% of the variance in long-term changes in moth abundance reported by the Rothamsted Insect Survey for the years 1968–2002. This is the first demonstration that artificial night-time lighting has had, in combination with other factors, a significant influence on levels of abundance of moth populations.     

Synthesis and ligand substitution reactions of [Ta(CO)5NH3]

Protonation of Na₃[Ta(CO)₅] in liquid ammonia provides the thermally unstable Na[Ta(CO)₅NH₃], which may be isolated as the crystalline and deep violet salt [Ph₄As][Ta(CO)₅NH₃]. Sodium amminepentacarbonyltantalate(1−) reacts with PMe₃, PPh₃, P(OMe)₃, AsPh₃, SbPh₃, CNtBu and CN⁻ at about 0°C in NH₃/THF to give exclusively the corresponding [Ta(CO)₅L]^z. These have been isolated as tetraethylammonium salts in 54–84% yields.     

A PATO-compliant zebrafish screening database (MODB): management of morpholino knockdown screen information

Background  

The zebrafish is a powerful model vertebrate amenable to high throughput in vivo genetic analyses. Examples include reverse genetic screens using morpholino knockdown, expression-based screening using enhancer trapping and forward genetic screening using transposon insertional mutagenesis. We have created a database to facilitate web-based distribution of data from such genetic studies.