Analysis of the Human Mucosal Response to Cholera Reveals Sustained Activation of Innate Immune Signaling Pathways

To better understand the innate immune response to Vibrio cholerae infection, we tracked gene expression in the duodenal mucosa of 11 Bangladeshi adults with cholera, using biopsy specimens obtained immediately after rehydration and 30 and 180 days later. We identified differentially expressed genes and performed an analysis to predict differentially regulated pathways and upstream regulators. During acute cholera, there was a broad increase in the expression of genes associated with innate immunity, including activation of the NF-kappaB, mitogen-activated protein kinase (MAPK), and Toll-like receptor (TLR)-mediated signaling pathways, which, unexpectedly, persisted even 30 days after infection. Focusing on early differences in gene expression, we identified 37 genes that were differentially expressed on days 2 and 30 across the 11 participants. These genes included the endosomal Toll-like receptor gene TLR8, which was expressed in lamina propria cells. Underscoring a potential role for endosomal TLR-mediated signaling in vivo, our pathway analysis found that interferon regulatory factor 7 and beta 1 and alpha 2 interferons were among the top upstream regulators activated during cholera. Among the innate immune effectors, we found that the gene for DUOX2, an NADPH oxidase involved in the maintenance of intestinal homeostasis, was upregulated in intestinal epithelial cells during cholera. Notably, the observed increases in DUOX2 and TLR8 expression were also modeled in vitro when Caco-2 or THP-1 cells, respectively, were stimulated with live V. cholerae but not with heat-killed organisms or cholera toxin alone. These previously unidentified features of the innate immune response to V. cholerae extend our understanding of the mucosal immune signaling pathways and effectors activated in vivo following cholera

Analysis of the Human Mucosal Response to Cholera Reveals Sustained Activation of Innate Immune Signaling Pathways

To better understand the innate immune response to Vibrio cholerae infection, we tracked gene expression in the duodenal mucosa of 11 Bangladeshi adults with cholera, using biopsy specimens obtained immediately after rehydration and 30 and 180 days later. We identified differentially expressed genes and performed an analysis to predict differentially regulated pathways and upstream regulators. During acute cholera, there was a broad increase in the expression of genes associated with innate immunity, including activation of the NF-kappaB, mitogen-activated protein kinase (MAPK), and Toll-like receptor (TLR)-mediated signaling pathways, which, unexpectedly, persisted even 30 days after infection. Focusing on early differences in gene expression, we identified 37 genes that were differentially expressed on days 2 and 30 across the 11 participants. These genes included the endosomal Toll-like receptor gene TLR8, which was expressed in lamina propria cells. Underscoring a potential role for endosomal TLR-mediated signaling in vivo, our pathway analysis found that interferon regulatory factor 7 and beta 1 and alpha 2 interferons were among the top upstream regulators activated during cholera. Among the innate immune effectors, we found that the gene for DUOX2, an NADPH oxidase involved in the maintenance of intestinal homeostasis, was upregulated in intestinal epithelial cells during cholera. Notably, the observed increases in DUOX2 and TLR8 expression were also modeled in vitro when Caco-2 or THP-1 cells, respectively, were stimulated with live V. cholerae but not with heat-killed organisms or cholera toxin alone. These previously unidentified features of the innate immune response to V. cholerae extend our understanding of the mucosal immune signaling pathways and effectors activated in vivo following cholera

Markers Associated with Sex Differences in Methamphetamine-Induced Striatal Dopamine Neurotoxicity

Three different approaches were employed to assess various markers associated with sex differences in responses to methamphetamine (MA). Bioassay measures reveal that MA treatment results in significantly greater reductions in body weight and increases in body temperature in male mice. Protein and mRNA determinations show significant increases in Bcl-2 and PAI-1 in male mice, while females show significant increases in GFAP and decreases in IGF-1R following treatment with MA. In mice with a heterozygous mutation of their dopamine transporter (+/- DAT), only female mice show significant differences in dopamine transporter binding and mRNA and associated reductions in striatal dopamine content along with increases in MA-evoked striatal dopamine output. The identification of these sex-dependent differences in markers provides a foundation for more exhaustive evaluation of their impact upon, and treatment of, disorders/neurotoxicity of the nigrostriatal dopaminergic system and the bases for the differences that exist between females and males

Maternal and cord blood hemoglobin as determinants of placental weight: A cross-sectional study

Background: Both high and low placental weights are associated with adverse pregnancy outcomes. Maternal hemoglobin levels can influence placental weight, but the evidence is conflicting. Since maternal hemoglobin does not invariably correlate with fetal/neonatal blood hemoglobin levels, we sought to determine whether cord blood hemoglobin or maternal hemoglobin status more closely associates with placental weight in women undergoing elective cesarean section at term. Methods: This was a cross-sectional study conducted at the Royal Alexandra Hospital, Edmonton, Canada, involving 202 women with term singleton pregnancies undergoing elective cesarean section. Maternal blood and mixed cord blood hemoglobin levels were analyzed using a HemoCue Hb201+ system. Birth weight, placental weight, one-and five-minute APGAR scores, American Society of Anesthesiologists physical state classification, maternal age, and maternal height were also recorded. Relationships between maternal and cord blood hemoglobin levels with placental weight, birth weight, and birth weight to placental weight ratio were the main outcome measures. Results: A total of 182 subjects were included in the analysis. Regression analysis showed that cord blood hemoglobin, but not maternal hemoglobin, was inversely related with placental weight (β = −2.4, p = 0.001) and positively related with the birth weight to placental weight ratio (β = 0.015, p = 0.001 and p = 0.63, respectively). Conclusions: Our findings suggest that measuring cord blood hemoglobin levels, rather than maternal hemoglobin levels, may provide important diagnostic information about in utero fetal adaptation to suboptimal placental function and neonatal health

A Unifying Model of Genome Evolution Under Parsimony

We present a data structure called a history graph that offers a practical basis for the analysis of genome evolution. It conceptually simplifies the study of parsimonious evolutionary histories by representing both substitutions and double cut and join (DCJ) rearrangements in the presence of duplications. The problem of constructing parsimonious history graphs thus subsumes related maximum parsimony problems in the fields of phylogenetic reconstruction and genome rearrangement. We show that tractable functions can be used to define upper and lower bounds on the minimum number of substitutions and DCJ rearrangements needed to explain any history graph. These bounds become tight for a special type of unambiguous history graph called an ancestral variation graph (AVG), which constrains in its combinatorial structure the number of operations required. We finally demonstrate that for a given history graph $G$, a finite set of AVGs describe all parsimonious interpretations of $G$, and this set can be explored with a few sampling moves.Comment: 52 pages, 24 figure

Subacute Bacterial Endocarditis with Leptotrichia goodfellowii in a Patient with a Valvular Allograft: A Case Report and Review of the Literature

Leptotrichia species are normal constituents of the oral cavity and the genitourinary tract microbiota that are known to provoke disease in immunocompromised patients and rarely in immunocompetent individuals. Following the description of Leptotrichia goodfellowii sp. nov., two cases of endocarditis by this species have been reported. Here, we report a case of Leptotrichia goodfellowii endocarditis in an immunocompetent patient with a valvular allograft. The isolation and identification of Leptotrichia can be challenging, and it is likely that infection with this pathogen is significantly underdiagnosed. A definitive identification, as in this case, most often requires 16S rRNA gene sequencing, highlighting the increasingly important role of this diagnostic modality among immunocompetent patients with undetermined anaerobic bacteremia

Immunoseq: the identification of functionally relevant variants through targeted capture and sequencing of active regulatory regions in human immune cells

$\textbf{BACKGROUND}$: The observation that the genetic variants identified in genome-wide association studies (GWAS) frequently lie in non-coding regions of the genome that contain cis-regulatory elements suggests that altered gene expression underlies the development of many complex traits. In order to efficiently make a comprehensive assessment of the impact of non-coding genetic variation in immune related diseases we emulated the whole-exome sequencing paradigm and developed a custom capture panel for the known DNase I hypersensitive site (DHS) in immune cells - "Immunoseq". $\textbf{RESULTS}$: We performed Immunoseq in 30 healthy individuals where we had existing transcriptome data from T cells. We identified a large number of novel non-coding variants in these samples. Relying on allele specific expression measurements, we also showed that our selected capture regions are enriched for functional variants that have an impact on differential allelic gene expression. The results from a replication set with 180 samples confirmed our observations. $\textbf{CONCLUSIONS}$: We show that Immunoseq is a powerful approach to detect novel rare variants in regulatory regions. We also demonstrate that these novel variants have a potential functional role in immune cells.This work was supported by grants from the Canadian Institute of Health Research (CIHR), the UK Medical Research Council (G1100125), the Swedish Research Council (DO283001) and Knut and Alice Wallenberg Foundation (KAW). We also acknowledge the use of subjects from the Cambridge BioResource and the support of the Cambridge NIHR Biomedical Research Centre. AM was supported by the Fond de Recherche Santé Québec Doctoral training award. TP and CL holds a Canada Research Chair

Imagining worse than reality: comparing beliefs and intentions between disaster evacuees and survey respondents

We often credit disasters, and their coverage in the media, with changes in the public perception of risk associated with low-probability, high-consequence events (LPHCs). With a change in perceptions, we also expect changes in beliefs, preferences, and behaviors. Do beliefs and behaviors change in different ways for people who live through these LPHC critical events, as opposed to people who observe them? This study compares hypothetical hurricanes with actual hurricane effects in a survey quasi-experiment. Findings indicate that hypothetical disasters induce stronger reactions than those experienced in the natural world, as Hurricane Katrina bystanders imagine themselves incurring much higher damages, and being much less likely to return to live in their hurricane-damaged homes, than actual Hurricane Katrina evacuees. Ultimately, respondents considering a hypothetical low-probability, high-consequence event exhibit exaggerated beliefs and opposite decisions of those who actually lived through one of these events. Results underline the importance of examining the differences between public perceptions and experiential reality