Effectiveness of Vocal Training Techniques in School-Aged Drama Students.

OBJECTIVES: The purpose of this study was to determine whether vocal hygiene education and direct vocal training would impact student self-reported preparedness for using voice for performance. STUDY DESIGN: A single-group, pretest-posttest research design was used. METHODS: Twenty-three drama students in middle and high school participated in a 1-hour vocal training workshop, which included vocal hygiene education and vocal training for performance. Changes in student self-reported preparedness for using voice for performance were examined following participation in the workshop. Data analysis involved comparison of pretest and posttest responses to a novel questionnaire. RESULTS: Participants demonstrated a statistically significant increase in self-reported preparedness for using voice for performance following participation (P < .001, d = 2.40), as measured by mean increase in survey scores. Additionally, significant group differences were found by grade level and report of prior vocal training. CONCLUSIONS: School-aged drama students appear receptive to direct vocal training and vocal hygiene education, with significant gains in self-reported preparedness for using voice for performance observed following intervention.

The Metabolic Response of Various Cell Lines to Microtubule-Driven Uptake of Lipid- and Polymer-Coated Layer-by-Layer Microcarriers.

Lipid structures, such as liposomes or micelles, are of high interest as an approach to support the transport and delivery of active agents as a drug delivery system. However, there are many open questions regarding their uptake and impact on cellular metabolism. In this study, lipid structures were assembled as a supported lipid bilayer on top of biopolymer-coated microcarriers based on the Layer-by-Layer assembly strategy. The functionalized microcarriers were then applied to various human and animal cell lines in addition to primary human macrophages (MΦ). Here, their influence on cellular metabolism and their intracellular localization were detected by extracellular flux analysis and immunofluorescence analysis, respectively. The impact of microcarriers on metabolic parameters was in most cell types rather low. However, lipid bilayer-supported microcarriers induced a decrease in oxygen consumption rate (OCR, indicative for mitochondrial respiration) and extracellular acidification rate (ECAR, indicative for glycolysis) in Vero cells. Additionally, in Vero cells lipid bilayer microcarriers showed a more pronounced association with microtubule filaments than polymer-coated microcarrier. Furthermore, they localized to a perinuclear region and induced nuclei with some deformations at a higher rate than unfunctionalized carriers. This association was reduced through the application of the microtubule polymerization inhibitor nocodazole. Thus, the effect of respective lipid structures as a drug delivery system on cells has to be considered in the context of the respective target cell, but in general can be regarded as rather low.

Publisher Correction: Exercise-induced bronchoconstriction, temperature regulation and the role of heat shock proteins in non-asthmatic recreational marathon and half-marathon runners.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Exercise-induced bronchoconstriction, temperature regulation and the role of heat shock proteins in non-asthmatic recreational marathon and half-marathon runners.

Exercise is the most common trigger of bronchospasm. Heat shock protein (HSP) expression was linked to asthmatic patients. The prevalence and pathophysiology of exercise-induced bronchoconstriction (EIB) in non-professional non-asthmatic runners is unknown. We sought to investigate the frequency of EIB and cytokine changes in non-professional non-asthmatic marathon and half marathoners with and without EIB. Testing was performed before the marathon (baseline), immediately post-marathon at the finish area (peak), and 2-7 days after the marathon (recovery): immunosorbent assays for measurement of HSP70, blood count analysis, spirometry and temperature measurements. We experienced a decline in FEV1 of ≥10% in 35.29% of marathon and 22.22% of half marathon runners. Runners with EIB had significantly higher HSP70 serum concentrations at baseline than those without EIB (987.4 ± 1486.7 vs. 655.6 ± 1073.9; p = 0.014). Marathoners with EIB had significantly increased WBC before participating in the competition (7.4 ± 1.7 vs. 6.0 ± 1.5; p = 0.021). After recovery we found increased HSP70 serum concentrations in marathoners with EIB compared to those without (2539.2 ± 1692.5 vs. 1237.2 ± 835.2; p = 0.032), WBC (7.6 ± 1.8 vs. 6.4 ± 1.6; p = 0.048) and PLT (273.0 ± 43.0 vs 237.2 ± 48.3; p = 0.040). At all measured skin sites skin temperatures in runners were significantly lower immediately after participating in the competition when compared to temperature before the race (skin temperature baseline vs. peak: abdominal: 33.1 ± 0.2 vs. 30.0 ± 0.4; p < 0.001; upper arm: 31.6 ± 0.2 vs. 29.4 ± 0.3; p < 0.001; upper leg: 30.7 ± 0.3 vs. 29.4 ± 0.2; p = 0.014; lower leg: 30.6 ± 1.0 vs. 30.2 ± 1.5; p = 0.007). We found a higher than expected number of non-professional athletes with EIB. HSP70 serum concentrations and elevated WBC could indicate a predisposition to EIB.

Association Between the 25-Hydroxyvitamin D Status and Physical Performance in Healthy Recreational Athletes.

Molecular and clinical studies have linked vitamin D (vitD) deficiency to several aspects of muscle performance. For this retrospective cross-sectional study data from 297 male (M) and 284 female (F) healthy recreational athletes were used to evaluate the prevalence of vitD deficiency in athletes living in Austria and to determine whether serum 25-hydroxyvitamin D (25(OH)D) correlates with maximal (Pmax) and submaximal physical performance (Psubmax) measured on a treadmill ergometer. The data were controlled for age, season, weekly training hours (WTH), body mass index (BMI) and smoking status. 96 M and 75 F had 25(OH)D levels ≤ 20 ng/mL. 25(OH)D levels showed seasonal variations, but no seasonal differences in Pmax and Psubmax were detected. M with 25(OH)D levels ≤ 20 ng/mL had significantly lower Psubmax (p = 0.045) than those with normal levels. In F no significant differences in Pmax or Psubmax were detected. Stepwise multiple regression analysis including all covariates revealed significant correlations between 25(OH)D levels and Pmax (ß = 0.138, p = 0.003) and Psubmax (ß = 0.152, p = 0.002) in M. Interestingly, for F significant correlations between 25(OH)D and both Pmax and Psubmax disappeared after adding WTH to the model. In conclusion, our data suggest that 25(OH)D status is associated with physical performance especially in M, while in F, WTH and BMI seem to affect the correlation.

Confidence in outcome estimates from systematic reviews used in informed consent.

OBJECTIVES: Evidence-based dentistry now guides informed consent in which clinicians are obliged to provide patients with the most current, best evidence, or best estimates of outcomes, of regimens, therapies, treatments, procedures, materials, and equipment or devices when developing personal oral health care, treatment plans. Yet, clinicians require that the estimates provided from systematic reviews be verified to their validity, reliability, and contextualized as to performance competency so that clinicians may have confidence in explaining outcomes to patients in clinical practice. ANALYSIS WITH RESULTS: The purpose of this paper was to describe types of informed estimates from which clinicians may have confidence in their capacity to assist patients in competent decision-making, one of the most important concepts of informed consent. METHODS: Using systematic review methodology, researchers provide clinicians with valid best estimates of outcomes regarding a subject of interest from best evidence. Best evidence is verified through critical appraisals using acceptable sampling methodology either by scoring instruments (Timmer analysis) or checklist (grade), a Cochrane Collaboration standard that allows transparency in open reviews. These valid best estimates are then tested for reliability using large databases. Finally, valid and reliable best estimates are assessed for meaning using quantification of margins and uncertainties. ANALYSIS: Through manufacturer and researcher specifications, quantification of margins and uncertainties develops a performance competency continuum by which valid, reliable best estimates may be contextualized for their performance competency: at a lowest margin performance competency (structural failure), high margin performance competency (estimated true value of success), or clinically determined critical values (clinical failure). CONCLUSIONS: Informed consent may be achieved when clinicians are confident of their ability to provide useful and accurate best estimates of outcomes regarding regimens, therapies, treatments, and equipment or devices to patients in their clinical practices and when developing personal, oral health care, treatment plans.

Non-professional marathon running: RAGE axis and ST2 family changes in relation to open-window effect, inflammation and renal function.

Conflicting data exist on the relevance of marathon (M) and half marathon (HM) running for health. The number of non-professional athletes finishing M and HM events is steadily growing. In order to investigate molecular changes occurring in amateur athletes, we enrolled 70 non-professional runners finishing a single M (34) or HM (36) event at baseline, the finish line and during recovery, and 30 controls. The measurement of the Receptor for Advanced Glycation Endproducts, Interleukin 1 receptor antagonist, ST2 and cytokeratin 18 was combined with molecules measured during clinical routine. Results were analyzed in the light of blood cell analysis, lactate measurements, correction for changes in plasma volume and body composition assessments. There were intrinsic differences in body mass index, abdominal body fat percentage and training time between M and HM runners. C-reactive protein changes in M and HM runners. While soluble RAGE, AGEs and ST2 increased immediately after the race in HM runners, HMGB1 increased in HM and M after the race and declined to baseline after a recovery period. We give insights into the regulation of various molecules involved in physical stress reactions and their possible implications for the cardiovascular system or renal function.

Brightly blue and green emitting Cu(I) dimers for singlet harvesting in OLEDs.

With the chelating aminophosphane ligands Ph2P-(o-C6H4)-N(CH3)2 (PNMe2) and Ph2P-(o-C6H4)-NC4H8 (PNpy), the four halide (Cl, Br, I)-bridged copper coordination compounds [Cu(µ-Cl)(PNMe2)]2 (1), [Cu(µ-Br)(PNMe2)]2 (2), [Cu(µ-I)(PNMe2)]2 (3), and [Cu(µ-I)(PNpy)]2 (4) were synthesized and structurally characterized. Their photophysical properties were studied in detail. The complexes exhibit strong blue (λmax = 464 (3) and 465 nm (4)) and green (λmax = 506 (1) and 490 nm (2)) luminescence as powders with quantum yields of up to 65% at decay times as short as 4.1 µs. An investigation of the emission decay behavior between 1.3 and 300 K gives insight into the nature of the emitting states. At temperatures below T ≈ 60 K, the decay times of the studied compounds are several hundred microseconds long, which indicates that the emission originates from a triplet state (T1 state). DFT calculations show that this state is of (metal+halide)-to-ligand charge transfer (3)(M+X)LCT character. Investigations at 1.3 K allow us to gain insight into the three triplet substates, in particular, to determine the individual substate decay times being as long as a few milliseconds. The zero-field splittings are smaller than 1 or 2 cm(-1). With an analysis of these data, conclusions about the effectiveness of spin-orbit coupling (SOC) can be drawn. Interestingly, the large differences of SOC constants of the halides are not obviously displayed in the triplet state properties. With a temperature increase from T ≈ 60 to 300 K, a significant decrease of the emission decay time by almost 2 orders of magnitude is observed, and at ambient temperature, the decay times amount only to ∼4-7 µs without a significant reduction of the emission quantum yields. This drastic decrease of the (radiative) decay time is a result of the thermal population of a short-lived singlet state (S1 state) that lies energetically only a few hundred wavenumbers (460-630 cm(-1)) higher than the T1 state. Such an emission mechanism corresponds to a thermally activated delayed fluorescence (TADF). At ambient temperature, almost only a delayed fluorescence (∼98%) is observed. Compounds showing this mechanism are highly attractive for applications in OLEDs or LEECs as, in principle, it is possible to harvest all singlet and triplet excitons for the generation of light in the lowest excited singlet state. This effect represents the singlet harvesting mechanism.

How slug herbivory of juvenile hybrid willows alters chemistry, growth and subsequent susceptibility to diverse plant enemies.

BACKGROUND AND AIMS: Selective feeding by herbivores, especially at the seedling or juvenile phase, has the potential to change plant traits and ultimately the susceptibility of surviving plants to other enemies. Moreover, since hybridization is important to speciation and can lead to introgression of traits between plant species, differential feeding (herbivore-induced mortality) can influence the expression of resistance traits of hybrids and ultimately determine the consequences of hybridization. While it would be expected that herbivore-induced mortality would lead to greater resistance, there may be trade-offs whereby resistance to one herbivore increases susceptibility to others. The hypothesis was tested that the exotic slug, Arion subfuscus, causes non-random survival of hybrid willows and alters plant: (1) susceptibility to slugs; (2) secondary and nutritional chemistry, and growth; and (3) susceptibility to other phytophages. METHODS: Two populations of plants, control and selected, were created by placing trays of juvenile willows in the field and allowing slugs access to only some. When ≤10 individuals/tray remained (approx. 85 % mortality), 'selected' and undamaged 'control' trays were returned to a common area. Traits of these populations were then examined in year 1 and in subsequent years. KEY RESULTS: The selected population was less palatable to slugs. Surprisingly, foliar concentrations of putative defence traits (phenolic glycosides and tannins) did not differ between treatments, but the selected population had higher foliar nitrogen and protein, lower carbon to nitrogen ratio and greater above-ground biomass, indicating that vigorously growing plants were inherently more resistant to slugs. Interestingly, selected plants were more susceptible to three phytophages: an indigenous pathogen (Melampsora epitea), a native herbivorous beetle (Chrysomela knabi) and an exotic willow leaf beetle (Plagiodera versicolora). CONCLUSIONS: This exotic slug changed the population structure of F2 hybrid willows in unanticipated ways. Defence expression remained unchanged, while nutritional and growth traits changed. These changes caused plants to be more susceptible to other plant enemies. Other exotic herbivore species are anticipated to have similar direct and indirect effects on native plant populations.

Protein storage and root:shoot reallocation provide tolerance to damage in a hybrid willow system.

To determine the mechanistic basis of tolerance, we evaluated six candidate traits for tolerance to damage using F(2) interspecific hybrids in a willow hybrid system. A distinction was made between reproductive tolerance and biomass tolerance; reproductive tolerance was designated as a plant's proportional change in catkin production following damage, while biomass tolerance referred to a plant's proportional change in biomass (i.e., regrowth) following damage. F(2) hybrids were generated to increase variation and independence among candidate traits. Using three clonally identical individuals, pre-damage candidate traits for tolerance to damage (root:shoot ratio, total nonstructural carbohydrate, and total available protein) and post-damage candidate traits (relative root:shoot ratio, phenolic ratio, and specific leaf area ratio) were measured. The range of variation for these six candidate traits was broad. Biomass was significantly increased two years after 50% shoot length removal, and catkin production was not significantly reduced when damaged, suggesting that F(2) hybrids had great biomass tolerance and reproductive tolerance. Based on multiple regression methods, increased reproductive tolerance was associated with increased protein storage and decreased relative root:shoot ratio (reduced root allocation after damage). In addition, a positive relationship between biomass tolerance and condensed tannins was detected, and both traits were associated with increased reproductive tolerance. These four factors explained 57% of the variance in the reproductive tolerance of F(2) hybrids, but biomass tolerance explained the majority of the variance in reproductive tolerance. Changes in plant architecture in response to plant damage may be the underlying mechanism that explains biomass tolerance.

Subunit vaccine efficacy against Botulinum neurotoxin subtypes.

Botulinum neurotoxins (BoNT) are classified into 7 serotypes (A-G) based upon neutralization by serotype-specific anti-sera. Several recombinant serotype-specific subunit BoNT vaccines have been developed, including a subunit vaccine comprising the receptor binding domain (HCR) of the BoNTs. Sequencing of the genes encoding BoNTs has identified variants (subtypes) that possess up to 32% primary amino acid variation among different BoNT serotypes. Studies were conducted to characterize the ability of the HCR of BoNT/A to protect against challenge by heterologous BoNT/A subtypes (A1-A3). High dose vaccination with HCR/A subtypes A1-A4 protected mice from challenge by heterologous BoNT/A subtype A1-A3, while low dose HCR vaccination yielded partial protection to heterologous BoNT/A subtype challenge. Absolute IgG titers to HCRs correlated to the dose of HCR used for vaccination, where HCR/A1 elicited an A1 subtype-specific IgG response, which was not observed with HCR/A2 vaccination. Survival of mice challenged to heterologous BoNT/A2 following low dose HCR/A1 vaccination correlated with elevated IgG titers directed to the denatured C-terminal sub-domain of HCR/A2, while survival of mice to heterologous BoNT/A1 following low dose HCR/A2 vaccination correlated to elevated IgG titers directed to native HCRc/A1. This implies that low dose vaccinations with HCR/A subtypes elicit unique IgG responses, and provides a basis to define how the host develops a neutralizing immune response to BoNT intoxication. These results may provide a reference for the development of pan-BoNT vaccines.

Homoleptic coinage metal compounds of group(IV)heteroborates.

This article describes the synthesis and characterization of the first silver complex with the germylene [GeB11H11](2-) and coinage metal complexes with the stannylene ligand [SnB11H11](2-). Starting materials like CuCl, AuCl(Me2S), and AgNO3 were used to give mononuclear (3 and 4), dinuclear (5), hexanuclear (6), and heptanuclear (7) coordination compounds: [Et4N]5[Cu(CH3CN)(SnB11H11)3] (3), [Et4N]5[Ag(SnB11H11)3] (4), [Et4N]6[{Au(SnB11H11)2}2] (5), [Et4N]6[{Ag(GeB11H11)}6] (6), and [Et4N]9[Ag7(SnB11H11)8] (7). In case of the oligonuclear compounds 5-7 silver and gold aggregation was observed under formation of metal-metal bonds. Furthermore, the germa-closo-dodecaborate is found in a hitherto unknown µ3-bridging coordination mode connecting three silver atoms. The new compounds were characterized by single crystal X-ray diffraction and in the case of 3-6 also by NMR spectroscopy and elemental analysis.

Growth and chemical defense in willow seedlings: trade-offs are transient.

Many studies have failed to detect costs of defense and some have even found a positive correlation between growth and the concentrations of chemical defenses. These studies contradict the theoretical assumption that anti-herbivore defenses are costly-produced at the expense of growth and/or reproduction. Costs, however, may be transient and therefore difficult to detect. Here we tested the hypothesis that costs of defense would be pronounced early in development when root growth is prioritized (high percent root allocation), but not later in development. To test this hypothesis, we grew F(2) hybrid willow seedlings from five different families, and harvested cohorts of even-aged seedlings after 6, 7, 8 and 9 weeks of growth. Seedlings were divided into root and shoot tissue and shoots were analyzed for phenolics (condensed tannins and phenolic glycosides). We found evidence for transient costs of defense. The concentrations of phenolics were negatively correlated with total biomass, shoot biomass, and the proportion of biomass allocated to roots in week 6. After week 6, however, the concentrations of phenolics were positively correlated with shoot biomass and total biomass, while phenolics were uncorrelated with the proportion of biomass allocated to roots. These results, the first ever, to our knowledge, with woody plants, suggest that costs of defense were transient; specifically, costs were found in early development, when root establishment was a priority. Our findings suggest that studies should focus more on trade-offs early in plant development.

Fitness and genetic architecture of parent and hybrid willows in common gardens.

Models of hybrid zone dynamics incorporate different patterns of hybrid fitness relative to parental species fitness. An important but understudied source of variation underlying these fitness differences is the environment. We investigated the performance of two willow species and their F1, F2, and backcross hybrids using a common-garden experiment with six replicated gardens that differed in soil moisture. Aboveground biomass, catkin production, seed production per catkin, and seed germination rate were significantly different among genetic classes. For aboveground biomass and catkin production, hybrids generally had intermediate or inferior performance compared to parent species. Salix eriocephala had the highest performance for all performance measures, but in two gardens F, plants had superior or equal performance for aboveground biomass and female catkin production. Salix eriocephala and backcrosses to S. eriocephala had the highest numbers of filled seeds per catkin and the highest estimates of total fitness in all gardens. Measures of filled seeds per catkin and germination rate tend to support the model of endogenous hybrid unfitness, and these two measures had major effects on estimates of total seed production per catkin. We also estimated how the two willow species differ genetically in these fitness measures using line cross analysis. We found a complex genetic architecture underlying the fitness differences between species that involved additive, dominance, and epistatic genetic effects for all fitness measures. The environment was important in the expression of these genetic differences, because the type of epistasis differed among the gardens for above-ground biomass and for female catkin production. These findings suggest that fine-scale environmental variation can have a significant impact on hybrid fitness in hybrid zones where parents and hybrids are widely interspersed.

Characterization of the antibody response to the receptor binding domain of botulinum neurotoxin serotypes A and E.

Clostridium botulinum neurotoxins (BoNTs) are the most toxic proteins for humans. The current clostridial-derived vaccines against BoNT intoxication have limitations including production and accessibility. Conditions were established to express the soluble receptor binding domain (heavy-chain receptor [HCR]) of BoNT serotypes A and E in Escherichia coli. Sera isolated from mice and rabbits immunized with recombinant HCR/A1 (rHCR/A1) from the classical type A-Hall strain (ATCC 3502) (BoNT/A1) and rHCR/E from BoNT serotype E Beluga (BoNT/E(B)) neutralized the homologous serotype of BoNT but displayed differences in cross-recognition and cross-protection. Enzyme-linked immunosorbent assay and Western blotting showed that alpha-rHCR/A1 recognized epitopes within the C terminus of the HCR/A and HCR/E, while alpha-rHCR/E recognized epitopes within the N terminus or interface between the N and C termini of the HCR proteins. alpha-rHCR/E(B) sera possessed detectable neutralizing capacity for BoNT/A1, while alpha-rHCR/A1 did not neutralize BoNT/E. rHCR/A was an effective immunogen against BoNT/A1 and the Kyoto F infant strain (BoNT/A2), but not BoNT serotype E Alaska (BoNT/E(A)), while rHCR/E(B) neutralized BoNT/E(A), and under hyperimmunization conditions protected against BoNT/A1 and BoNT/A2. The protection elicited by rHCR/A1 to BoNT/A1 and BoNT/A2 and by rHCR/E(B) to BoNT/E(A) indicate that immunization with receptor binding domains elicit protection within sub-serotypes of BoNT. The protection elicited by hyperimmunization with rHCR/E against BoNT/A suggests the presence of common neutralizing epitopes between the serotypes E and A. These results show that a receptor binding domain subunit vaccine protects against serotype variants of BoNTs.

Plant genetic differences influence herbivore community structure: evidence from a hybrid willow system.

To determine the influence of plant genetic variation on community structure of insect herbivores, we examined the abundances of 14 herbivore species among six genetic classes of willow: Salix eriocephala, S. sericea, their F(1) and F(2) interspecific hybrids, and backcross hybrids to each parental species. We placed 1-year-old plants, grown from seeds generated from controlled crosses, in a common garden. During the growing season, we censused gall-inducing flies and sawflies, leaf-mining insects, and leaf-folding Lepidoptera to determine the community structure of herbivorous insects on the six genetic classes. Our results provided convincing evidence that the community structure of insect herbivores in this hybrid willow system was shaped by genetic differences among the parental species and the hybrid genetic classes. Using MANOVA, we detected significant differences among genetic classes for both absolute and relative abundance of herbivores. Using canonical discriminant analysis, we found that centroid locations describing community structure of the insect herbivores differed for each genetic class. Moreover, the centroids for the four hybrid classes were located well outside of the range between the centroids for the parental species, suggesting that more than additive genetic effects of the two parental species influenced community formation on hybrid classes. Line-cross analysis suggested that plant genetic factors responsible for structuring the herbivore community involved epistatic effects, as well as additive and dominance effects. We discuss the ramifications of these results in regard to the structure of insect herbivore communities on plants and the implications of our findings for the evolution of interspecific interactions.

Infection with Mycobacterium bovis BCG diverts traffic of myelin oligodendroglial glycoprotein autoantigen-specific T cells away from the central nervous system and ameliorates experimental autoimmune encephalomyelitis.

Infectious agents have been proposed to influence susceptibility to autoimmune diseases such as multiple sclerosis. We induced a Th1-mediated central nervous system (CNS) autoimmune disease, experimental autoimmune encephalomyelitis (EAE) in mice with an ongoing infection with Mycobacterium bovis strain bacillus Calmette-Guérin (BCG) to study this possibility. C57BL/6 mice infected with live BCG for 6 weeks were immunized with myelin oligodendroglial glycoprotein peptide (MOG(35-55)) to induce EAE. The clinical severity of EAE was reduced in BCG-infected mice in a BCG dose-dependent manner. Inflammatory-cell infiltration and demyelination of the spinal cord were significantly lessened in BCG-infected animals compared with uninfected EAE controls. ELISPOT and gamma interferon intracellular cytokine analysis of the frequency of antigen-specific CD4(+) T cells in the CNS and in BCG-induced granulomas and adoptive transfer of MOG(35-55)-specific green fluorescent protein-expressing cells into BCG-infected animals indicated that nervous tissue-specific (MOG(35-55)) CD4(+) T cells accumulate in the BCG-induced granuloma sites. These data suggest a novel mechanism for infection-mediated modulation of autoimmunity. We demonstrate that redirected trafficking of activated CNS antigen-specific CD4(+) T cells to local inflammatory sites induced by BCG infection modulates the initiation and progression of a Th1-mediated CNS autoimmune disease.

Generation and characterization of a protective monoclonal antibody to Pseudomonas aeruginosa PcrV.

Pseudomonas aeruginosa is a gram-negative pathogen causing life-threatening infections. Lung injury and the development of sepsis depend largely on the expression of type III secretion system (TTSS) virulence. TTSS functions as a molecular syringe to deliver toxins directly to the cytosol of cells, inhibit innate immune mechanisms, and prevent bacterial clearance. Polyclonal antibodies that bind to PcrV of P. aeruginosa inhibit the delivery of type III toxins and enhance the clearance of bacteria during acute lung infections. PcrV is a homologue of LcrV, a protective antigen in the Yersinia TTSS and an integral component of TTSS. In this study, a murine monoclonal antibody (MAb) to PcrV was generated: MAb 166, which is protective against P. aeruginosa when coinstilled with the bacterial inoculum or intraperitoneally transferred to mice. Fab fragments from MAb 166 prevent sepsis and death. The epitope bound by MAb 166 was mapped to the carboxyl-terminus of PcrV.

Seedling herbivory by slugs in a willow hybrid system: developmental changes in damage, chemical defense, and plant performance.

We evaluated feeding preference and damage by the slug, Arion subfuscus, on seedlings of two willow species, Salix sericea and S. eriocephala, and their F1 interspecific hybrids. Trays of seedlings were placed in the field and excised leaves were presented to slugs in choice tests. Slugs preferred feeding on and caused the most damage to S. eriocephala seedlings. S. sericea seedlings were least preferred and least damaged. F1 hybrid seedlings were intermediate in preference and damage. Slug preference of and damage to these seedlings decreased over time, suggesting developmental changes in resistance. Seedlings were sampled for phenolic glycoside and tannin chemistry weekly to coincide with the field and laboratory experiments. Concentrations of phenolic glycosides and tannins increased linearly with seedling age, coincident with changes in slug preference and damage, indicating a developmental change in defense. Slug deterrence was not detected at low concentrations of salicortin when painted on leaves or discs, but both salicortin and condensed tannins deterred slug feeding at concentrations between 50 and 100 mg/g, levels found in adult willows. Seedling performance was related to damage inflicted by slugs. Due to lower levels of damage when exposed to slugs in the field, S. sericea plants had significantly greater biomass than S. eriocephala plants. Biomass of F1 hybrids was equal to S. sericea when damaged. However, undamaged S. eriocephala and F1 hybrid plants had the greatest biomass. Because F1 hybrid seedlings performed as well as the most fit parent in all cases, slugs could be an important selective factor favoring introgression of defensive traits between these willow species.