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We report on data and debriefing observations in the context of an immersive simulation conducted to (a) train clinicians and (b) test new protocols and kits, developed in table-top exercises without prior clinical experience to fit anticipated clinical encounters in the setting of the rapidly expanding COVID-19 pandemic. We simulated scenarios with particular relevance for anesthesiology, perioperative and critical care, including (1) cardiac arrest, (2) emergency airway management, (3) tele-instruction for remote guidance and supervision, and (4) transporting an intubated patient. Using a grounded theory approach, three authors (MHA, DLR, EHS) developed emergent themes. First alone and then together, we sought consensus in uncovering overarching themes and constructs from the debriefings. We thus performed an informal qualitative thematic analysis based in a critical realist epistemological position - the understanding that our findings, while real, are affected by situational variables and the observer's perspective[1,2]. We compared data from videos and triangulated the data by member checking. All participants and course instructors volunteered to participate in this educational project and contributed as co-authors to this manuscript. During debriefing, we applied crisis resource management concepts including situation awareness, prioritization of tasks, and clear communication practices, conducting the debriefing with emphasis on current TeamStepps 2.0 terminology and concepts. [3,4] In addition, we re-evaluated formerly familiar processes, as shortcomings of protocols, kits, and interdisciplinary cooperation became apparent. The data provide detailed observations on how immersive simulation and debriefing among peers mitigated the unfamiliarity of individual clinicians and the organization at large with the demands of an unprecedented healthcare crisis. We also observed and report on the anxiety caused by resource constraints, risk to clinicians in the face of limited personal equipment, and the overall uncertainty surrounding COVID-19. We began to summarize, interpret, critique, and discuss our data and debriefing observations in a rapid co-publication in the Journal of Clinical Anesthesia. [Healthcare Simulation to Prepare for the COVID-19 Pandemic][5].

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ES-62 is a glycoprotein secreted by the filarial nematode Acanthocheilonema viteae that protects against ovalbumin (OVA)-induced airway hyper-responsiveness in mice by virtue of covalently attached anti-inflammatory phosphorylcholine (PC) residues. We have recently generated a library of small molecule analogues (SMAs) of ES-62 based around its active PC moiety as a starting point in novel drug development for asthma and identified two compounds - termed 11a and 12b - that mirror ES-62's protective effects. In this study, we have moved away from OVA, a model allergen, to test the SMAs against two clinically relevant allergens - house dust mite (HDM) and cockroach allergen (CR) extract. We show that both SMAs offer some protection against development of lung allergic responses to CR, in particular reducing eosinophil infiltration, whereas only SMA 12b is effective in protecting against eosinophil-dependent HDM-induced allergy. These data therefore suggest that helminth molecule-induced protection against model allergens may not necessarily translate to clinically relevant allergens. Nevertheless, in this study, we have managed to demonstrate that it is possible to produce synthetic drug-like molecules based on a parasitic worm product that show therapeutic potential with respect to asthma resulting from known triggers in humans.

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Chronic asthma is associated with persistent lung inflammation and long-term remodelling of the airways that have proved refractory to conventional treatments such as steroids, despite their efficacy in controlling acute airway contraction and bronchial inflammation. As its recent dramatic increase in industrialised countries has not been mirrored in developing regions, it has been suggested that helminth infection may protect humans against developing asthma. Consistent with this, ES-62, an immunomodulator secreted by the parasitic worm Acanthocheilonema viteae, can prevent pathology associated with chronic asthma (cellular infiltration of the lungs, particularly neutrophils and mast cells, mucus hyper-production and airway thickening) in an experimental mouse model. Importantly, ES-62 can act even after airway remodelling has been established, arresting pathogenesis and ameliorating the inflammatory flares resulting from repeated exposure to allergen that are a debilitating feature of severe chronic asthma. Moreover, two chemical analogues of ES-62, 11a and 12b mimic its therapeutic actions in restoring levels of regulatory B cells and suppressing neutrophil and mast cell responses. These studies therefore provide a platform for developing ES-62-based drugs, with compounds 11a and 12b representing the first step in the development of a novel class of drugs to combat the hitherto intractable disorder of chronic asthma.

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Streptococcus agalactiae infections in fish are predominantly caused by beta-haemolytic strains of clonal complex (CC) 7, notably its namesake sequence type (ST) 7, or by non-haemolytic strains of CC552, including the globally distributed ST260. In contrast, CC23, including its namesake ST23, has been associated with a wide homeothermic and poikilothermic host range, but never with fish. The aim of this study was to determine whether ST23 is virulent in fish and to identify genomic markers of fish adaptation of S. agalactiae. Intraperitoneal challenge of Nile tilapia, Oreochromis niloticus (Linnaeus), showed that ST260 is lethal at doses down to 10(2) cfu per fish, whereas ST23 does not cause disease at 10(7) cfu per fish. Comparison of the genome sequence of ST260 and ST23 with those of strains derived from fish, cattle and humans revealed the presence of genomic elements that are unique to subpopulations of S. agalactiae that have the ability to infect fish (CC7 and CC552). These loci occurred in clusters exhibiting typical signatures of mobile genetic elements. PCR-based screening of a collection of isolates from multiple host species confirmed the association of selected genes with fish-derived strains. Several fish-associated genes encode proteins that potentially provide fitness in the aquatic environment.

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INTRODUCTION: ES-62, a phosphorylcholine (PC)-containing immunomodulator secreted by the parasitic worm Acanthocheilonema viteae, protects against nephritis in the MRL/Lpr mouse model of systemic lupus erythematosus (SLE). However, ES-62 is not suitable for development as a therapy and thus we have designed drug-like small molecule analogues (SMAs) based around its active PC-moiety. To provide proof of concept that ES-62-based SMAs exhibit therapeutic potential in SLE, we have investigated the capacity of two SMAs to protect against nephritis when administered to MRL/Lpr mice after onset of kidney damage. METHODS: SMAs 11a and 12b were evaluated for their ability to suppress antinuclear antibody (ANA) generation and consequent kidney pathology in MRL/Lpr mice when administered after the onset of proteinuria. RESULTS: SMAs 11a and 12b suppressed development of ANA and proteinuria. Protection reflected downregulation of MyD88 expression by kidney cells and this was associated with reduced production of IL-6, a cytokine that exhibits promise as a therapeutic target for this condition. CONCLUSIONS: SMAs 11a and 12b provide proof of principle that synthetic compounds based on the safe immunomodulatory mechanisms of parasitic worms can exhibit therapeutic potential as a novel class of drugs for SLE, a disease for which current therapies remain inadequate.

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A similarity decay law is proposed for enstrophy of a one-signed-vorticity fluid in a circular free-slip domain. It excludes the metastable equilibrium enstrophy which cannot drive turbulence, and approaches Batchelor's t(-2) law for strong turbulence. Measurements of the decay of a turbulent electron fluid agree well with the predictions of the decay law for a variety of initial conditions.

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Dynamical relaxation of a pure electron plasma in a Malmberg-Penning trap is studied, comparing experiments, numerical simulations and statistical theories of weakly dissipative two-dimensional (2D) turbulence. Simulations confirm that the dynamics are approximated well by a 2D hydrodynamic model. Statistical analysis favors a theoretical picture of relaxation to a near-maximum entropy state with constrained energy, circulation, and angular momentum. This provides evidence that 2D electron fluid relaxation in a turbulent regime is governed by principles of maximum entropy.

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A detailed study was conducted on the mating behaviour of Bactrocera cacuminata (Hering) (Diptera: Tephritidae) in nature. Plant tissues from Solanum mauritianum Scopoli, the primary larval host for B. cacuminata, were also analysed for methyl eugenol content. In the field, over a 15 month period, 44,171 observations of adult B. cacuminata individuals were made including 1109 mating pairs on S. mauritianum. Calling behaviour consisting of wing fanning and anus beating by males was also consistently observed on the underside of leaves of S. mauritianum after sunset. Female flies that arrived into these groups of 10-15 calling males were mated and often remained coupled until dawn. No methyl eugenol was detected from the analysis of leaves, flowers and fruits of S. mauritianum. Thus, B. cacuminata does not need to aggregate at sites where methyl eugenol is present and the hypothesis that this chemical plays a role in the selection of mating sites by B. cacuminata is not supported by the current study. It is concluded that S. mauritianum is the primary site of mating for B. cacuminata in nature and that the concept that the larval host plant is the centre of activity for dacine fruit flies remains robust, being fully supported by the results of this study.

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We designed 4 primer pairs to amplify conserved regions of the E1 or nsP4 genes of salmonid alphavirus (SAV) and evaluated their performance in optimized 1-step SYBR green real-time RT-PCR (RRT-PCR) assays. A single primer pair, amplifying a 227 bp segment of E1 was then chosen for further study. This RRT-PCR was shown to be highly repeatable and reproducible over a wide range of RNA dilutions, with a linear relationship between cycle threshold (Ct) value and RNA concentration over a 10(7) dilution range. The limit of detection was calculated to be < or = 1.5 TCID50 ml(-1). When applied to sera previously screened by virus isolation for SAV viraemia, the RRT-PCR correctly identified all 13 culture-positive samples, as well as finding an additional 28 sera positive. Relative semi-quantitation of sera showed a very highly significant relationship between copy number and TCID50 (p < 0.001, R2 = 0.9563). Following experimental infection of salmon, heart samples were consistently positive until 21 d post infection (dpi), with (weak) positive signals still detectable in 50% of fish 70 dpi.

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OBJECTIVE: To compare the efficacy and safety of rofecoxib 12.5 mg once daily to naproxen 500 mg twice daily in patients > or = 40 years of age with knee or hip osteoarthritis (OA). METHOD: Two identical 6-week, randomized, double-blind studies were conducted (1 in Africa, Australia, Europe, Canada, Mexico, & South America; 1 in Asia). Primary endpoints were pain walking on a flat surface, patient global assessment of response to therapy, and investigator global assessment of disease status. RESULTS: Overall, 944 patients participated. For all efficacy endpoints, treatment effects for rofecoxib and naproxen were comparable and seen at the first measures of efficacy. Both compounds were generally well-tolerated, with an improved gastrointestinal safety profile for rofecoxib versus naproxen. CONCLUSIONS In these studies, rofecoxib 12.5 mg once daily (the lowest indicated dose) and naproxen 500 mg twice daily showed similar treatment effects in OA patients. Rofecoxib and naproxen were generally well tolerated.

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The delta selectivity of the opioid heptapeptides deltorphin I and II has been attributed to the C-terminal 'address' domain, the hydrophobic Val(5)-Val(6) residues apparently playing a topographical role. We now report the synthesis, opioid binding affinities, and a QSAR study of a series of peptides in which one of the valine side chains was altered. QSAR analyses included previously published models for a binding pocket interaction and an optimum size (Schullery, S.; Mohammedshah, T.; Makhlouf, H.; Marks, E.; Wilenkin, B.; Escobar, S.; Mousigian, C.; Heyl, D. Bioorg. Med. Chem. 1997, 5, 2221), and a new approach for backbone conformational effects using Langevin dynamics simulation (PM3 semi-empirical force field) of an isolated peptide fragment containing the side chain and flanking peptide bonds. No evidence is found of binding pocket interactions or optimum size for either the position-5 or -6 side chain. Rather, delta binding is generally disfavored while mu binding is either unaffected (position-5) or favored (position-6) by larger side chains. The dynamics results provide evidence of similar 'local' conformation roles for the positions 5 and 6 side chains. Specifically, delta binding is favored by side chains that maximize the extension of the backbone, measured as the through-space distance between peptide fragment ends, the angle between lines connecting the alpha-carbon with fragment ends, or the difference between the psi and phi peptide angles.

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OBJECTIVE: To compare the incidence of selected spontaneously reported adverse events (AEs) in patients with osteoarthritis (OA) treated with rofecoxib (VIOXX, 12.5 mg qd) or Arthrotec (diclofenac 50 mg/misoprostol 200 mcg bid). METHODS: Double-blind, parallel-group, 6-week study of patients aged > or = 40 years with a clinical diagnosis of OA treated with rofecoxib or Arthrotec. Primary endpoint: self-reported diarrhea; secondary endpoints: abdominal pain, discontinuations due to AEs, GI AEs and NSAID-type GI AEs (ie., acid reflux, dyspepsia, epigastric discomfort, heartburn, nausea, vomiting). RESULTS: Among 483 patients (80.3% females, mean age 62.1), the rofecoxib group vs the Arthrotec group respectively reported diarrhea 6.2% vs 16.2% (p<0.001); drug-related diarrhea 3.7% vs 16.2% (p<0.001); one or more clinical AEs 52.9% vs 73.0% (p<0.001); GI AEs 28.9% vs 48.5% (p<0.001); NSAID-type GI AEs 18.6% vs 29.9% (p=0.004); discontinuations due to abdominal pain 0.4% vs 3.7% (p<0.05); and discontinuations due to any AE 4.1% vs 9.1% (p=0.029). No significant differences were observed in efficacy. CONCLUSION: Rofecoxib 12.5 mg qd has improved GI tolerability and similar efficacy compared to Arthrotec (diclofenac 50 mg/misoprostol 200 mcg bid).

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The zinc metallopeptidase neurolysin is shown by x-ray crystallography to have large structural elements erected over the active site region that allow substrate access only through a deep narrow channel. This architecture accounts for specialization of this neuropeptidase to small bioactive peptide substrates without bulky secondary and tertiary structures. In addition, modeling studies indicate that the length of a substrate N-terminal to the site of hydrolysis is restricted to approximately 10 residues by the limited size of the active site cavity. Some structural elements of neurolysin, including a five-stranded beta-sheet and the two active site helices, are conserved with other metallopeptidases. The connecting loop regions of these elements, however, are much extended in neurolysin, and they, together with other open coil elements, line the active site cavity. These potentially flexible elements may account for the ability of the enzyme to cleave a variety of sequences.

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Neuropeptidases inactivate or modify the activity of peptide neurotransmitters and neurohormones. The neuropeptidase neurolysin acts only on short peptides and accepts a variety of cleavage-site sequences. Structures of the enzyme and enzyme-substrate complexes will help to determine the mechanisms of substrate selectivity used by this enzyme. Crystals of recombinant neurolysin have been grown in the orthorhombic space group P2(1)2(1)2, with unit-cell parameters a = 157.8, b = 88.0, c = 58.4 A. Data have been collected to 2.3 A at 110 K with observed diffraction to 1.8 A. Circular dichroism measurements suggest that the enzyme is primarily alpha-helical, with little beta-strand secondary structure. Sequence-based secondary-structure prediction supports this conclusion.

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Billing data from the Health Care Financing Administration (HCFA) indicated that the influenza immunization rates for dialysis patients in the United States do not meet the goal of 60% set by Healthy People 2000, and fall significantly short of the goal of 90% of all Medicare beneficiaries as outlined in Healthy People 2010. Influenza and pneumonia together are the sixth leading cause of death in the United States. Despite the known benefits of influenza vaccination in reducing morbidity and mortality, only 40% to 50% of high-risk patients are immunized. Although HCFA/Medicare billing data may not provide the best measurement of actual practice, it is currently the only measure available from any national source. The data suggest that there is a need for improvement. Because the HCFA/Medicare rates were based only on those immunizations for which Medicare was billed, End-Stage Renal Disease Network 15 embarked on a project to determine a more accurate rate of immunization within the Network based on information provided by the dialysis facilities. Influenza vaccination rates for the winter 1998 flu season ranged from 51.5% to 84.9% for the states in the Network; the rate for the whole Network was 74.6%. The HCFA/Medicare billed influenza immunization rates were 26.5 to 45.6 percentage points lower.

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We recently identified the existence of a novel interaction between heat shock transcription factor 2 (HSF2) and the PR65/A subunit of protein phosphatase 2A (PP2A) and showed that HSF2 is able to compete with the PP2A catalytic subunit for binding to PR65. To elucidate the mechanistic basis of this competition between HSF2 and catalytic subunit at the molecular level we have sought to characterize sequences within PR65 that are important for interaction with HSF2. The results identify the intra-repeat loop within HEAT repeat 11 of PR65 as critical for interaction with HSF2. Analysis of point mutants within this loop region of PR65 identify lysine 416 as a residue critical for interaction with HSF2. Interestingly, this same lysine residue of PR65 is important for its binding to catalytic subunit. These results suggest that HSF2's ability to interfere with catalytic subunit binding to PR65 is due to competition between HSF2 and catalytic subunit for at least one amino acid residue of PR65, lysine 416. These data support the hypothesis that HSF2 represents a new type of PP2A regulatory protein.

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The ability of Nicotiana tabacum cell cultures to utilize farnesol (F-OH) for sterol and sesquiterpene biosynthesis was investigated. [(3)H]F-OH was readily incorporated into sterols by rapidly growing cell cultures. However, the incorporation rate into sterols was reduced by greater than 70% in elicitor-treated cell cultures whereas a substantial proportion of the radioactivity was redirected into capsidiol, an extracellular sesquiterpene phytoalexin. The incorporation of [(3)H]F-OH into sterols was inhibited by squalestatin 1, suggesting that [(3)H]F-OH was incorporated via farnesyl pyrophosphate (F-P-P). Consistent with this possibility, N. tabacum proteins were metabolically labeled with [(3)H]F-OH or [(3)H]geranylgeraniol ([(3)H]GG-OH). Kinase activities converting F-OH to farnesyl monophosphate (F-P) and, subsequently, F-P-P were demonstrated directly by in vitro enzymatic studies. [(3)H]F-P and [(3)H]F-P-P were synthesized when exogenous [(3)H]F-OH was incubated with microsomal fractions and CTP. The kinetics of formation suggested a precursor-product relationship between [(3)H]F-P and [(3)H]F-P-P. In agreement with this kinetic pattern of labeling, [(32)P]F-P and [(32)P]F-P-P were synthesized when microsomal fractions were incubated with F-OH and F-P, respectively, with [gamma-(32)P]CTP serving as the phosphoryl donor. Under similar conditions, the microsomal fractions catalyzed the enzymatic conversion of [(3)H]GG-OH to [(3)H]geranylgeranyl monophosphate and [(3)H]geranylgeranyl pyrophosphate ([(3)H]GG-P-P) in CTP-dependent reactions. A novel biosynthetic mechanism involving two successive monophosphorylation reactions was supported by the observation that [(3)H]CTP was formed when microsomes were incubated with [(3)H]CDP and either F-P-P or GG-P-P, but not F-P. These results document the presence of at least two CTP-mediated kinases that provide a mechanism for the utilization of F-OH and GG-OH for the biosynthesis of isoprenoid lipids and protein isoprenylation.

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