The Conserved G-Protein Coupled Receptor FSHR-1 Regulates Protective Host Responses to Infection and Oxidative Stress

The innate immune system’s ability to sense an infection is critical so that it can rapidly respond if pathogenic microorganisms threaten the host, but otherwise maintain a quiescent baseline state to avoid causing damage to the host or to commensal microorganisms. One important mechanism for discriminating between pathogenic and non-pathogenic bacteria is the recognition of cellular damage caused by a pathogen during the course of infection. InCaenorhabditis elegans, the conserved G-protein coupled receptor FSHR-1 is an important constituent of the innate immune response. FSHR-1 activates the expression of antimicrobial infection response genes in infected worms and delays accumulation of the ingested pathogenPseudomonas aeruginosa. FSHR-1 is central not only to the worm’s survival of infection by multiple pathogens, but also to the worm’s survival of xenobiotic cadmium and oxidative stresses. Infected worms produce reactive oxygen species to fight off the pathogens; FSHR-1 is required at the site of infection for the expression of detoxifying genes that protect the host from collateral damage caused by this defense response. Finally, the FSHR-1 pathway is important for the ability of worms to discriminate pathogenic from benign bacteria and subsequently initiate an aversive learning program that promotes selective pathogen avoidance

FSHR-1 is required for the induction of the oxidative stress response by PA14.

<p><i>ldIs3[gcs-1</i>::<i>gfp]</i> (A, B) or <i>fshr-1(ok778); ldIs3[gcs-1</i>::<i>gfp]</i> (C, D) worms were exposed to OP50 (A, C) or PA14 (B, D) for 5 hours. Representative worms show that in a wild-type background, <i>gcs-1</i>::<i>gfp</i> is induced by pathogen exposure; this induction depends on <i>fshr-1</i>. Scale bars = 100 μm. (E) Quantification of the mean fluorescence intensity of the intestine for each condition (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0137403#sec009" target="_blank">Methods</a>). Error bars are SEM. One-way ANOVA and Tukey HSD test, **P<0.01.</p

Pathogen avoidance contributes to the pathogen sensitivity of <i>fshr-1</i> mutants.

<p>The survival of worms was measured when exposed to a standard small lawn of PA14 or a big lawn that covered the entire surface of the agar. (A) Representative killing assay. (B) Mean survival time was measured and compared using one-way ANOVA and Tukey HSD test, **P<0.01. Error bars are standard deviation (A) or SEM (B).</p

FSHR-1 is required for the survival of heavy metal and oxidative stress.

<p>Wild-type, <i>fshr-1(ok778)</i> mutants, and mutants rescued with <i>fshr-1(+)</i> in the intestine were measured for their ability to survive different types of stress. Worms were subjected to 100 μM cadmium (A, B), 5 mM paraquat (C, D), or 37°C (E, F). Representative survival curves for approximately 80–100 worms for each condition are shown in (A, C, and E) with standard deviation error bars. The mean survival time for each genotype was calculated for at least three independent experiments (B, D, F). Error bars are SEM. One-way ANOVA and Tukey HSD test, *P<0.05, **P<0.01.</p

FSHR-1 is required for the defense against diverse pathogens.

<p>Representative wild-type (A) and <i>fshr-1(ok778)</i> mutant (B) worms fed GFP-PA14 for 18 hours. Scale bars = 100 μm. (C) Quantification of the sum of the intestinal fluorescence intensity for at least 10 representative individual worms per condition. (D) Mean survival time of wild-type and <i>fshr-1(ok778)</i> mutant worms exposed to different bacterial food sources. * P<0.05, **P<0.01, *** P<0.0001 in unpaired t-test. Error bars are SEM. (E) Functional annotation of genes whose mean expression from three microarray replicates in wild-type worms infected with PA14 for 4 hours was at least 2-fold higher than their mean expression in <i>fshr-1(ok778)</i> mutants infected with PA14 for 4 hours, with P<0.05. Genes known to be involved both in infection response and stress response were grouped with stress response.</p

FSHR-1 promotes the avoidance of pathogenic PA14.

<p>The occupancy of wild-type, <i>fshr-1(ok778)</i>, and <i>ok778; agIs35[gut</i>::<i>fshr-1(+)]</i> worms on a lawn of relatively non-pathogenic <i>E</i>. <i>coli</i> OP50 (A, B) or pathogenic <i>P</i>. <i>aeruginosa</i> PA14 (C, D) was measured <1 hour (A, C) and 9 hours (B, D) after transferring worms to the lawn. Error bars are SEM. One-way ANOVA and Tukey HSD test, *P<0.05, **P<0.01.</p

Scapula fractures: interobserver reliability of classification and treatment

OBJECTIVES:There is substantial variation in the classification and the management of scapula fractures. The first purpose of this study was to analyze the interobserver reliability of the OTA/AO and the New International Classification of scapula fractures. The second purpose was to assess the proportion of agreement among orthopaedic surgeons on operative or nonoperative treatment. DESIGN:: Web-based reliability study SETTING:: Independent orthopaedic surgeons from several countries were invited to classify scapular fractures in an online survey. PARTICIPANTS:One-hundred and three orthopaedic surgeons evaluated 35 movies of 3DCT-reconstruction of selected scapular fractures, representing a full spectrum of fracture patterns. MAIN OUTCOME MEASUREMENTS:Fleiss' kappa (κ) was used to assess the reliability of agreement between the surgeons. RESULTS:: The overall agreement on the OTA/AO Classification was moderate for the types (A, B, and C, κ = 0.54) with a 71% proportion of rater agreement (PA) as well as for the nine groups (A1 to C3, κ = 0.47) with a 57% PA. For the New International Classification, the agreement about the intra-articular extension of the fracture (Fossa (F), κ = 0.79) was substantial, the agreement about a fractured body (Body (B), κ = 0.57) or process was moderate (Process (P), κ = 0.53), however PAs were more than 81%. The agreement on the treatment recommendation was moderate (κ = 0.57) with a 73% PA. CONCLUSIONS:The New International Classification was more reliable. Body and process fractures generated more disagreement than intra-articular fractures and need further clear definitions