A new species of <Emphasis Type="Italic">Isospora</Emphasis> Schneider, 1881 (Apicomplexa: Eimeriidae) from the twist-necked turtle <Emphasis Type="Italic">Platemys platycephala</Emphasis> (Schneider) (Testudines: Chelidae) in Brazil

A new coccidian species of the genus Isospora Schneider 1881 (Apicomplexa, Eimeriidae) is reported from a single specimen of chelid turtle, Platemys platycephala (Schneider, 1792), obtained in a flooded area of the Amazonian municipality of Altamira, in Pará State, northern Brazil. The oöcysts of Isospora platemysi n. sp. are subspheroidal, 19.0–24.0 × 22.5–18.5 (22.6 × 20.8) µm in size [length/width ratio 1.0–1.1 (1.1)], with a colourless wall, 1.0–1.9 (1.4) wide, with two smooth layers; polar granule is present, oöcyst residuum and micropyle are both absent. The sporocyst is ovoidal, 10.0–12.1 × 8.0–10.0 (11.0 × 9.1) µm [length/width ratio 1.1–1.3 (1.2), with a knob-like Stieda body. Sub-Stieda body is present, rounded irregular-trapezoidal; para-Stieda body is absent. Sporocyst residuum is dispersed and composed of granules of differing sizes. This is only the fifth record of Isospora in chelonians, and the first report of a coccidian parasite of the genus Platemys.     

Skp2B stimulates mammary gland development by inhibiting REA, the repressor of the estrogen receptor

Skp2B, an F-box protein of unknown function, is frequently overexpressed in breast cancer. In order to determine the function of Skp2B and whether it has a role in breast cancer, we performed a two-hybrid screen and established transgenic mice expressing Skp2B in the mammary glands. We found that Skp2B interacts with the repressor of estrogen receptor activity (REA) and that overexpression of Skp2B leads to a reduction in REA levels. In the mammary glands of MMTV-Skp2B mice, REA levels are also low. Our results show that in virgin transgenic females, Skp2B induces lobuloalveolar development and differentiation of the mammary glands normally observed during pregnancy. As this phenotype is identical to what was observed for REA heterozygote mice, our observations suggest that the Skp2B-REA interaction is physiologically relevant. However, in contrast to REA(+/-) mice, MMTV-Skp2B mice develop mammary tumors, suggesting that Skp2B affects additional proteins. These results indicate that the observed expression of Skp2B in breast cancer does contribute to tumorigenesis at least in part by modulating the activity of the estrogen receptor.     

Investigation into the diffusion of water into HEMA-co-MOEP hydrogels

Cross-linked homopolymers and copolymers of 2-hydroxyethyl methacrylate, HEMA, and ethylene glycol methacrylate phosphate, MOEP, have been synthesized, and the diffusion of water into these systems has been investigated. Only polymers with 0-20 mol % MOEP exhibited ideal swelling behavior as extensive fracturing occurred in the systems with greater than 20 mol % MOEP as the polymers began to swell during water sorption. Gravimetric studies were used in conjunction with magnetic resonance imaging of the diffusion front to elucidate the diffusion mechanism for these systems. In the case of the cross-linked HEMA homopolymer gels, the water transport mechanism was determined to be concentration-independent Fickian diffusion. However, as the fraction of MOEP in the network increased, the transport mechanism became increasingly exponentially concentration-dependent but remained Fickian until the polymer consisted of 30 mol % MOEP where the water transport could no longer been described by Fickian diffusion.     

Serum amyloid A activates the NLRP3 inflammasome and promotes Th17 allergic asthma in mice

IL-1β is a cytokine critical to several inflammatory diseases in which pathogenic Th17 responses are implicated. Activation of the NLRP3 inflammasome by microbial and environmental stimuli can enable the caspase-1-dependent processing and secretion of IL-1β. The acute-phase protein serum amyloid A (SAA) is highly induced during inflammatory responses, wherein it participates in systemic modulation of innate and adaptive immune responses. Elevated levels of IL-1β, SAA, and IL-17 are present in subjects with severe allergic asthma, yet the mechanistic relationship among these mediators has yet to be identified. In this study, we demonstrate that Saa3 is expressed in the lungs of mice exposed to several mixed Th2/Th17-polarizing allergic sensitization regimens. SAA instillation into the lungs elicits robust TLR2-, MyD88-, and IL-1-dependent pulmonary neutrophilic inflammation. Furthermore, SAA drives production of IL-1α, IL-1β, IL-6, IL-23, and PGE(2), causes dendritic cell (DC) maturation, and requires TLR2, MyD88, and the NLRP3 inflammasome for secretion of IL-1β by DCs and macrophages. CD4(+) T cells polyclonally stimulated in the presence of conditioned media from SAA-exposed DCs produced IL-17, and the capacity of polyclonally stimulated splenocytes to secrete IL-17 is dependent upon IL-1, TLR2, and the NLRP3 inflammasome. Additionally, in a model of allergic airway inflammation, administration of SAA to the lungs functions as an adjuvant to sensitize mice to inhaled OVA, resulting in leukocyte influx after Ag challenge and a predominance of IL-17 production from restimulated splenocytes that is dependent upon IL-1R signaling.     

Expansion in CD39+ CD4+ Immunoregulatory T Cells and Rarity of Th17 Cells in HTLV-1 Infected Patients Is Associated with Neurological Complications

HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develops HAM/TSP. CD4⁺ T cells are the main target of infection and play a pivotal role in regulating immunity to HTLV and are hypothesized to participate in the pathogenesis of HAM/TSP. The CD39 ectonucleotidase receptor is expressed on CD4⁺ T cells and based on co-expression with CD25, marks T cells with distinct regulatory (CD39⁺CD25⁺) and effector (CD39⁺CD25⁻) function. Here, we investigated the expression of CD39 on CD4⁺ T cells from a cohort of HAM/TSP patients, HTLV-1 asymptomatic carriers (AC), and matched uninfected controls. The frequency of CD39⁺ CD4⁺ T cells was increased in HTLV-1 infected patients, regardless of clinical status. More importantly, the proportion of the immunostimulatory CD39⁺CD25⁻ CD4⁺ T-cell subset was significantly elevated in HAM/TSP patients as compared to AC and phenotypically had lower levels of the immunoinhibitory receptor, PD-1. We saw no difference in the frequency of CD39⁺CD25⁺ regulatory (Treg) cells between AC and HAM/TSP patients. However, these cells transition from being anergic to displaying a polyfunctional cytokine response following HTLV-1 infection. CD39⁻CD25⁺ T cell subsets predominantly secreted the inflammatory cytokine IL-17. We found that HAM/TSP patients had significantly fewer numbers of IL-17 secreting CD4⁺ T cells compared to uninfected controls. Taken together, we show that the expression of CD39 is upregulated on CD4⁺ T cells HAM/TSP patients. This upregulation may play a role in the development of the proinflammatory milieu through pathways both distinct and separate among the different CD39 T cell subsets. CD39 upregulation may therefore serve as a surrogate diagnostic marker of progression and could potentially be a target for interventions to reduce the development of HAM/TSP.     

Comparative EST analysis provides insights into the basal aquatic fungus Blastocladiella emersonii

Background

Whole genome amplification is an increasingly common technique through which minute amounts of DNA can be multiplied to generate quantities suitable for genetic testing and analysis. Questions of amplification-induced error and template bias generated by these methods have previously been addressed through either small scale (SNPs) or large scale (CGH array, FISH) methodologies. Here we utilized whole genome sequencing to assess amplification-induced bias in both coding and non-coding regions of two bacterial genomes. Halobacterium species NRC-1 DNA and Campylobacter jejuni were amplified by several common, commercially available protocols: multiple displacement amplification, primer extension pre-amplification and degenerate oligonucleotide primed PCR. The amplification-induced bias of each method was assessed by sequencing both genomes in their entirety using the 454 Sequencing System technology and comparing the results with those obtained from unamplified controls.

Results

All amplification methodologies induced statistically significant bias relative to the unamplified control. For the Halobacterium species NRC-1 genome, assessed at 100 base resolution, the D-statistics from GenomiPhi-amplified material were 119 times greater than those from unamplified material, 164.0 times greater for Repli-G, 165.0 times greater for PEP-PCR and 252.0 times greater than the unamplified controls for DOP-PCR. For Campylobacter jejuni, also analyzed at 100 base resolution, the D-statistics from GenomiPhi-amplified material were 15 times greater than those from unamplified material, 19.8 times greater for Repli-G, 61.8 times greater for PEP-PCR and 220.5 times greater than the unamplified controls for DOP-PCR.

Conclusion

Of the amplification methodologies examined in this paper, the multiple displacement amplification products generated the least bias, and produced significantly higher yields of amplified DNA.     

Sighting of Stenella attenuata, the spotted dolphin, in Culebra Bay, Costa Rica, 1999-2000

Parallel to a zooplankton study (1999-2000) observations were made (from an inflatable boat), on the presence of dolphins along a transect (-8 km long) on the axis of Culebra Bay (24 km2), Gulf of Papagayo, Pacific coast of Costa Rica. Dolphins were found during 20 of the 31 boat surveys conducted. The only species of cetacean found in the bay was Stenella attenuata, the spotted dolphin. These sightings were more frequent during the rainy season, particularly during the month of May of both years. The presence of S. attenuata in Culebra Bay might be associated to the abundances of fish and mollusks (their presumed prey: for example, squids), as evidenced by fishery statistics available for this zone of the Pacific coast of Costa Rica.