Endothelial Protein C Receptor and Its Impact on Rheumatic Disease.

Endothelial Protein C Receptor (EPCR) is a key regulator of the activated protein C anti-coagulation pathway due to its role in the binding and activation of this protein. EPCR also binds to other ligands such as Factor VII and X, γδ T-cells, plasmodium falciparum erythrocyte membrane protein 1, and Secretory group V Phospholipases A2, facilitating ligand-specific functions. The functions of EPCR can also be regulated by soluble (s)EPCR that competes for the binding sites of membrane-bound (m)EPCR. sEPCR is created when mEPCR is shed from the cell surface. The propensity of shedding alters depending on the genetic haplotype of the EPCR gene that an individual may possess. EPCR plays an active role in normal homeostasis, anti-coagulation pathways, inflammation, and cell stemness. Due to these properties, EPCR is considered a potential effector/mediator of inflammatory diseases. Rheumatic diseases such as rheumatoid arthritis and systemic lupus erythematosus are autoimmune/inflammatory conditions that are associated with elevated EPCR levels and disease activity, potentially driven by EPCR. This review highlights the functions of EPCR and its contribution to rheumatic diseases.

Modelling shifts in social opinion through an application of classical physics.

This paper explores the abstraction of classical physics and applies several metrics that explore the evolution of social opinion. These metrics include an abstraction of Newtonian kinematics: mass, position, speed, acceleration, and Newtonian dynamics, an abstraction of force. Poll data is fit to a 2nd-order polynomial and a logistic function. These fits are used to understand the acceleration of opinion shift, and we explore recent social, cultural, and environmental trends, such as views on global climate change. We compare our results with the evolution of communication technologies and time spent on devices over the past 120 years. We show that the model connects the evolution in opinion with an abstraction of a Galilean concept: acceleration is independent of mass. Finally, we discuss the model of social polarization and the non-linear effect of media such as echo chambers.

Incidence of endophthalmitis after intravitreal injection of antivascular endothelial growth factor medications using topical lidocaine gel anesthesia.

PURPOSE: The purpose of this study was to determine the incidence of infectious endophthalmitis after intravitreal injection of antivascular endothelial growth factor medications using 2% topical lidocaine gel anesthesia. METHODS: Retrospective chart review of 4690 consecutive intravitreal injections of antivascular endothelial growth factor medications using 2% topical lidocaine gel anesthesia. All patients had at least 6 weeks of follow-up. RESULTS: A total of 608 patients underwent intravitreal injection of antivascular endothelial growth factor medications during the study period. There were 428 injections of pegaptanib sodium, 1841 injections of bevacizumab, and 2421 injections of ranibizumab. There were no cases of infectious endophthalmitis. The per-injection infection rate was 0.0% (95% confidence interval, 0.0-0.06%). CONCLUSION: The incidence of infectious endophthalmitis after intravitreal injection of antivascular endothelial growth factor medications using 2% topical lidocaine gel anesthesia is low.

Bacteriophages Reduce Pathogenic Escherichia coli Counts in Mice Without Distorting Gut Microbiota.

We performed a study to (i) investigate efficacy of an Escherichia coli/Salmonella spp./Listeria monocytogenes-targeting bacteriophage cocktail (tentatively named F.O.P.) to reduce a human pathogenic E. coli strain O157:H7 in experimentally infected mice, and (ii) determine how bacteriophages impact the normal gut microbiota when compared with antibiotic therapy. A total of 85 mice were inoculated with E. coli O157:H7 strain Ec231 [nalidixic acid resistant (NalAcR)] via oral gavage, and were randomized into six groups separated into three categories: 1st category received PBS or No phage/No PBS (control), 2nd category received either F.O.P., F.O.P. at 1:10 dilution, or only the E. coli phage component of F.O.P. (EcoShield PXTM), and 3rd category received the antibiotic ampicillin. All therapies were administered twice daily for four consecutive days including before and after bacterial challenge; except ampicillin which was administered only before and after bacterial challenge on day 0. Fecal samples were collected at Days 0, 1, 2, 3, 5, and 10. Samples were homogenized and plated on LB plates supplemented with NalAc to determine viable Ec231 counts. Body weights were measured at every fecal sample collection point. qPCR was performed using specific E. coli O157:H7 primers to quantify the number of E. coli O157:H7 genome copies. Microbiota community profiles were analyzed using Denature Gradient Gel Electrophoresis (DGGE) and 16S rRNA sequencing. F.O.P. significantly (P < 0.05) reduced E. coli O157:H7 pathogen counts by 54%. Ampicillin therapy significantly (P < 0.05) reduced E. coli O157:H7 pathogen counts by 79%. Greater initial weight-loss occurred in mice treated with ampicillin (-5.44%) compared to other treatment groups. No notable changes in the gut microbiota profiles were observed for control and F.O.P. groups. In contrast, the antibiotic group displayed noticeable distortion of the gut microbiota composition, only partially returning to normal by Day 10. In conclusion, we found that F.O.P. administration was effective in reducing viable E. coli O157:H7 in infected mice with a similar efficacy to ampicillin therapy. However, the F.O.P. bacteriophage preparation had less impact on the gut microbiota compared to ampicillin.

Fz2 and cdc42 mediate melanization and actin polymerization but are dispensable for Plasmodium killing in the mosquito midgut.

The midgut epithelium of the mosquito malaria vector Anopheles is a hostile environment for Plasmodium, with most parasites succumbing to host defenses. This study addresses morphological and ultrastructural features associated with Plasmodium berghei ookinete invasion in Anopheles gambiae midguts to define the sites and possible mechanisms of parasite killing. We show by transmission electron microscopy and immunofluorescence that the majority of ookinetes are killed in the extracellular space. Dead or dying ookinetes are surrounded by a polymerized actin zone formed within the basal cytoplasm of adjacent host epithelial cells. In refractory strain mosquitoes, we found that formation of this zone is strongly linked to prophenoloxidase activation leading to melanization. Furthermore, we identify two factors controlling both phenomena: the transmembrane receptor frizzled-2 and the guanosine triphosphate-binding protein cell division cycle 42. However, the disruption of actin polymerization and melanization by double-stranded RNA inhibition did not affect ookinete survival. Our results separate the mechanisms of parasite killing from subsequent reactions manifested by actin polymerization and prophenoloxidase activation in the A. gambiae-P. berghei model. These latter processes are reminiscent of wound healing in other organisms, and we propose that they represent a form of wound-healing response directed towards a moribund ookinete, which is perceived as damaged tissue.

The Inverse Poisson Functional for forecasting response time to environmental events and global climate change.

A series of Poisson distributions are fit to sets of global cost-of-impact data representing large-scale accidents and anthropogenic catastrophes. The fits are used to build a function representing data means and are designated the Inverse Poisson Functional. Climate and environmental data have been used to develop a cost-frequency population distribution and to estimate the expected time between events. On a global scale, we show that expected wait- or reaction- times can be estimated using the Poisson density function. The functional is generated, representing the locus of means (peaks) from the individual Poisson distributions from different impact costs. Past (ex-post) forecasts relate to a range of natural and anthropogenic disasters; future (ex-ante) forecast presents global CO2 emissions. This paper shows that a substantial reaction to global climate change (CO2 emissions extremum) will occur in 55 to 120 years (95% CI) with a model prediction of 80 years.

FoxP2 isoforms delineate spatiotemporal transcriptional networks for vocal learning in the zebra finch.

Human speech is one of the few examples of vocal learning among mammals yet ~half of avian species exhibit this ability. Its neurogenetic basis is largely unknown beyond a shared requirement for FoxP2 in both humans and zebra finches. We manipulated FoxP2 isoforms in Area X, a song-specific region of the avian striatopallidum analogous to human anterior striatum, during a critical period for song development. We delineate, for the first time, unique contributions of each isoform to vocal learning. Weighted gene coexpression network analysis of RNA-seq data revealed gene modules correlated to singing, learning, or vocal variability. Coexpression related to singing was found in juvenile and adult Area X whereas coexpression correlated to learning was unique to juveniles. The confluence of learning and singing coexpression in juvenile Area X may underscore molecular processes that drive vocal learning in young zebra finches and, by analogy, humans.

On the sustainability of an activity.

This paper develops a framework to determine the sustainability of a general activity. We define an activity as an action or process that uses one or more resources and that responds either wholly or partially to a demand. A definition for sustainability is developed and is contingent on whether or not an activity can be sustained according to the available resources, the duration of an activity, the cost of its execution, or whether substitution is possible. A sustainability condition is met when the duration, cost and the chain of dependent activities satisfies the demand. Two conditions for sustainability are developed: a strong condition when the demand is met with no substitution and a weak condition when the demand is met via substitution. In the latter case, we show that the set of all sustainable activities is a subset of a N-level union of sustainable activities and forms a topological cover.

New insights into Drosophila larval haemocyte functions through genome-wide analysis.

Drosophila blood cells or haemocytes comprise three cell lineages, plasmatocytes, crystal cells and lamellocytes, involved in immune functions such as phagocytosis, melanisation and encapsulation. Transcriptional profiling of activities of distinct haemocyte populations and from naive or infected larvae, was performed to find genes contributing to haemocyte functions. Of the 13 000 genes represented on the microarray, over 2500 exhibited significantly enriched transcription in haemocytes. Among these were genes encoding integrins, peptidoglycan recognition proteins (PGRPs), scavenger receptors, lectins, cell adhesion molecules and serine proteases. One relevant outcome of this analysis was the gain of new insights into the lamellocyte encapsulation process. We showed that lamellocytes require betaPS integrin for encapsulation and that they transcribe one prophenoloxidase gene enabling them to produce the enzyme necessary for melanisation of the capsule. A second compelling observation was that following infection, the gene encoding the cytokine Spatzle was uniquely upregulated in haemocytes and not the fat body. This shows that Drosophila haemocytes produce a signal molecule ready to be activated through cleavage after pathogen recognition, informing distant tissues of infection.

JNK signaling pathway is required for efficient wound healing in Drosophila.

Efficient wound healing including clotting and subsequent reepithelization is essential for animals ranging from insects to mammals to recover from epithelial injury. It is likely that genes involved in wound healing are conserved through the phylogeny and therefore, Drosophila may be an useful in vivo model system to identify genes necessary during this process. Furthermore, epithelial movement during specific developmental processes, such as dorsal closure, ressembles of those seen in mammalian wound healing. As puckered (puc) gene is a target of the JUN N-terminal kinase signaling pathway during dorsal closure, we investigated puc gene expression during wound healing in Drosophila. We showed that puc gene expression is induced at the edge of the wound in epithelial cells and Jun kinase is phosphorylated in wounded epidermal tissues, suggesting that the JUN N-terminal kinase signaling pathway is activated by a signal produced by an epidermal wound. In the absence of the Drosophila c-Fos homologue, puc gene expression is no longer induced. Finally, impaired epithelial repair in JUN N-terminal kinase deficient flies demonstrates that the JUN N-terminal kinase signaling is required to initiate the cell shape change at the onset of the epithelial wound healing. We conclude that the embryonic JUN N-terminal kinase gene cassette is induced at the edge of the wound. In addition, Drosophila appears as a good in vivo model to study morphogenetic processes requiring epithelial regeneration such as wound healing in vertebrates.

Pherokine-2 and -3.

Drosophila is a powerful model system to study the regulatory and effector mechanisms of innate immunity. To identify molecules induced in the course of viral infection in this insect, we have developed a model based on intrathoracic injection of the picorna-like Drosophila C virus (DCV). We have used MALDI-TOF mass spectrometry to compare the hemolymph of DCV infected flies and control flies. By contrast with the strong humoral response triggered by injection of bacteria or fungal spores, we have identified only one molecule induced in the hemolymph of virus infected flies. This molecule, pherokine-2 (Phk-2), is related to OS-D/A10 (Phk-1), which was previously characterized as a putative odor/pheromone binding protein specifically expressed in antennae. The virus-induced molecule is also similar to the product of the gene CG9358 (Phk-3), which is induced by septic injury. Both Phk-2 and Phk-3 are strongly expressed during metamorphosis, suggesting that they may participate in tissue-remodeling.

PVF2, a PDGF/VEGF-like growth factor, induces hemocyte proliferation in Drosophila larvae.

Blood cells play a crucial role in both morphogenetic and immunological processes in Drosophila, yet the factors regulating their proliferation remain largely unknown. In order to address this question, we raised antibodies against a tumorous blood cell line and identified an antigenic determinant that marks the surface of prohemocytes and also circulating plasmatocytes in larvae. This antigen was identified as a Drosophila homolog of the mammalian receptor for platelet-derived growth factor (PDGF)/vascular endothelial growth factor (VEGF). The Drosophila receptor controls cell proliferation in vitro. By overexpressing in vivo one of its putative ligands, PVF2, we induced a dramatic increase in circulating hemocytes. These results identify the PDGF/VEGF receptor homolog and one of its ligands as important players in Drosophila hematopoiesis.