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The high-consequence pathogen Bacillus anthracis causes human anthrax and often results in lethal infections without the rapid administration of effective antimicrobial treatment. Antimicrobial resistance profiling is therefore critical to inform post-exposure prophylaxis and treatment decisions, especially during emergencies such as outbreaks or where intentional release is suspected. Whole-genome sequencing using a rapid long-read sequencer can uncover antimicrobial resistance patterns if genetic markers of resistance are known. To identify genomic markers associated with antimicrobial resistance, we isolated B. anthracis derived from the avirulent Sterne strain with elevated minimal inhibitory concentrations to clarithromycin. Mutants were characterized both phenotypically through broth microdilution susceptibility testing and observations during culturing, as well as genotypically with whole-genome sequencing. We identified two different in-frame insertions in the L22 ribosomal protein-encoding gene rplV , which were subsequently confirmed to be involved in clarithromycin resistance through the reversion of the mutant gene to the parent (drug-susceptible) sequence. Detection of the rplV insertions was possible with rapid long-read sequencing, with a time-to-answer within 3 h. The mutations associated with clarithromycin resistance described here will be used in conjunction with known genetic markers of resistance for other antimicrobials to strengthen the prediction of antimicrobial resistance in B. anthracis .IMPORTANCEThe disease anthrax, caused by the pathogen Bacillus anthracis , is extremely deadly if not treated quickly and appropriately. Clarithromycin is an antibiotic recommended for the treatment and post-exposure prophylaxis of anthrax by the Centers for Disease Control and Prevention; however, little is known about the ability of B. anthracis to develop resistance to clarithromycin or the mechanism of that resistance. The characterization of clarithromycin-resistant isolates presented here provides valuable information for researchers and clinicians in the event of a release of the resistant strain. Additionally, knowledge of the genetic basis of resistance provides a foundation for susceptibility prediction through rapid genome sequencing to inform timely treatment decisions., Competing Interests: The authors declare no conflict of interest.

Machine learning interatomic potentials (MLIPs) have emerged as a technique that promises quantum theory accuracy for reduced cost. It has been proposed [ J. Chem. Phys . 2023 , 158 , 084111] that MLIPs trained on solely liquid water data cannot accurately transfer to the vapor-liquid equilibrium while recovering the many-body decomposition (MBD) analysis of gas-phase water clusters. This suggests that MLIPs do not directly learn the physically correct interactions of water molecules, limiting transferability. In this work, we show that MLIPs using equivariant architecture and trained on 3200 liquid water structures reproduces liquid-phase water properties (e.g., density within 0.003 g/cm 3 between 230 and 365 K), vapor-liquid equilibrium properties up to 550 K, the MBD analysis of gas-phase water cluster up to six-body interactions, and the relative energy and the vibrational density of states of ice phases. We show that potentials developed using equivariant MLIPs allow transferability for arbitrary phases of water that remain stable in nanosecond long simulations.

We review the GPAW open-source Python package for electronic structure calculations. GPAW is based on the projector-augmented wave method and can solve the self-consistent density functional theory (DFT) equations using three different wave-function representations, namely real-space grids, plane waves, and numerical atomic orbitals. The three representations are complementary and mutually independent and can be connected by transformations via the real-space grid. This multi-basis feature renders GPAW highly versatile and unique among similar codes. By virtue of its modular structure, the GPAW code constitutes an ideal platform for the implementation of new features and methodologies. Moreover, it is well integrated with the Atomic Simulation Environment (ASE), providing a flexible and dynamic user interface. In addition to ground-state DFT calculations, GPAW supports many-body GW band structures, optical excitations from the Bethe-Salpeter Equation, variational calculations of excited states in molecules and solids via direct optimization, and real-time propagation of the Kohn-Sham equations within time-dependent DFT. A range of more advanced methods to describe magnetic excitations and non-collinear magnetism in solids are also now available. In addition, GPAW can calculate non-linear optical tensors of solids, charged crystal point defects, and much more. Recently, support for graphics processing unit (GPU) acceleration has been achieved with minor modifications to the GPAW code thanks to the CuPy library. We end the review with an outlook, describing some future plans for GPAW., (© 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).)

Electrochemical scanning tunneling microscopy (EC-STM) and electrochemical quartz crystal microbalance (E-QCM) techniques in combination with DFT calculations have been applied to reveal the static phase and the phase transition of copper underpotential deposition (UPD) on a gold electrode surface. EC-STM demonstrated, for the first time, the direct visualization of the disintegration of (√3 × √3)R30° copper UPD adlayer with coadsorbed SO 4 2- while changing sample potential ( E S ) toward the redox Pa2/Pc2 peaks, which are associated with the phase transition between the Cu UPD (√3 × √3)R30° phase II and disordered randomly adsorbed phase III. DFT calculations show that SO 4 2- binds via three oxygens to the bridge sites of the copper with sulfate being located directly above the copper vacancy in the (√3 × √3)R30° adlayer, whereas the remaining oxygen of the sulfate points away from the surface. E-QCM measurement of the change of the electric charge due to Cu UPD Faradaic processes, the change of the interfacial mass due to the adsorption and desorption of Cu(II) and SO 4 2- , and the formation and stripping of UPD copper on the gold surface provide complementary information that validates the EC-STM and DFT results. This work demonstrated the advantage of using complementary in situ experimental techniques (E-QCM and EC-STM) combined with simulations to obtain an accurate and complete picture of the dynamic interfacial adsorption and UPD processes at the electrode/electrolyte interface.

Introduction: The Arkansas Trauma System was established by law more than a dozen years ago, and all participating trauma centers are required to maintain red blood cells. Since then, there has been a paradigm shift in resuscitating exsanguinating trauma patients. Damage Control Resuscitation with balanced blood products (or whole blood) and minimal crystalloid is now the standard of care. This project aimed to determine access to balanced blood products in our state's Trauma System (TS)., Methods: A survey of all trauma centers in the Arkansas TS was conducted, and geospatial analysis was performed. Immediately Available Balanced Blood (IABB) was defined as at least 2 units (U) of thawed plasma (TP) or never frozen plasma (NFP), 4 units of red blood cells (RBCs), 2 units of fresh frozen plasma (FFP), and 1 unit of platelets or 2 units of whole blood (WB)., Results: All 64 trauma centers in the state TS completed the survey. All level I, II, and III Trauma Centers (TCs) maintain RBC, plasma, and platelets, but only half of the level II and 16% of the level III TCs have thawed or never frozen plasma. A third of level IV TCs maintain only RBCs, while only 1 had platelets, and none had thawed plasma. 85% of people in our state are within 30 min of RBCs, almost two-thirds are within 30 min of plasma (TP, NFP, or FFP) and platelets, while only a third are within 30 min of IABB. More than 90% are within an hour of plasma and platelets, while only 60% are within that time from an IABB. The median drive times for Arkansas from RBC, plasma (TP, NFP, or FFP), platelets, and an immediately available and balanced blood bank are 19, 21, 32, and 59 minutes, respectively. A lack of thawed or non-frozen plasma and platelets are the most common limitations of IABB. One level III TC in the state maintains WB, which would alleviate the limited access to IABB., Conclusion: Only 16% of the trauma centers in Arkansas can provide IABB, and only 61% of the population can reach IABB within 60 minutes. Opportunities exist to reduce the time to balanced blood products by selectively distributing WB, TP, or NFP to hospitals in our state trauma system.

Bacillus anthracis, the causative agent of anthrax, is a high-consequence bacterial pathogen that occurs naturally in many parts of the world and is considered an agent of biowarfare or bioterrorism. Understanding antimicrobial susceptibility profiles of B. anthracis isolates is foundational to treating naturally occurring outbreaks and to public health preparedness in the event of an intentional release. In this systematic review, we searched the peer-reviewed literature for all publications detailing antimicrobial susceptibility testing of B. anthracis. Within the set of discovered articles, we collated a subset of publications detailing susceptibility testing that followed standardized protocols for Food and Drug Administration-approved, commercially available antimicrobials. We analyzed the findings from the discovered articles, including the reported minimal inhibitory concentrations. Across the literature, most B. anthracis isolates were reported as susceptible to current first-line antimicrobials recommended for postexposure prophylaxis and treatment. The data presented for potential alternative antimicrobials will be of use if significant resistance to first-line antimicrobials arises, the strain is bioengineered, or first-line antimicrobials are not tolerated or available., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2022. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Halogen bonding between two negatively charged species, tetraiodo-p-benzoquinone anion radicals (I 4 Q -. ) and iodide anions, was observed and characterized for the first time. X-ray structural and EPR/UV-Vis spectral studies revealed that the anion-anion bonding led to the formation of crystals comprising 2D layers of I 4 Q -. anion radicals linked by iodides and separated by Et 4 N + counter-ions. Computational analysis suggested that the seemingly antielectrostatic halogen bonds in these systems were formed via a combination of several factors. First, an attenuation of the interionic repulsion by the solvent facilitated close approach of the anions leading to their mutual polarization. This resulted in the appearance of positively charged areas (σ-holes) on the surface of the iodine substituents in I 4 Q -. responsible for the attractive interaction. Finally, the solid-state associations were also stabilized by multicenter (4:4) halogen bonding between I 4 Q -. and iodide., (© 2020 Wiley-VCH GmbH.)

Despite the progress in the study of anion-π interactions, there are still inconsistencies in the use of this term and the experimental data about factors affecting the strength of such bonding are limited. To shed light on these issues, we explored supramolecular associations between NCS - anions and a series of aromatic, olefinic or quinoidal π-acceptors. Combined experimental and computational studies revealed that all these complexes were formed by an attraction of the anion to the face of the π-system, and the arrangements of thiocyanate followed the areas of the most positive potentials on the surfaces of the π-acceptors. The stabilities of the complexes increased with the π-acceptor strength (reflected by their reduction potentials), and were essentially independent of the magnitudes of the maximum electrostatic potentials on their surfaces. The complexes showed intense absorption bands in the UV-Vis range, and the energies of these bands were correlated with the difference of the redox potentials of the anions and π-acceptors. Such features, as well as results of atoms-in-molecules and non-covalent index analyses suggested that besides electrostatics, molecular orbital interactions play a substantial role in the formation of these complexes. The unified trends in variations of the characteristics of the complexes between thiocyanate and a variety of π-acceptors point to their common nature. To embrace diversity and uniformity of the anion-π associates, we suggest (following the halogen bond's definition) that anion-π bonding occurs when there is evidence of a net attraction between the anions and the face of the electrophilic π-system.

Tuning surface strain is a powerful strategy for tailoring the reactivity of metal catalysts. Traditionally, surface strain is imposed by external stress from a heterogeneous substrate, but the effect is often obscured by interfacial reconstructions and nanocatalyst geometries. Here, we report on a strategy to resolve these problems by exploiting intrinsic surface stresses in two-dimensional transition metal nanosheets. Density functional theory calculations indicate that attractive interactions between surface atoms lead to tensile surface stresses that exert a pressure on the order of 10 5 atmospheres on the surface atoms and impart up to 10% compressive strain, with the exact magnitude inversely proportional to the nanosheet thickness. Atomic-level control of thickness thus enables generation and fine-tuning of intrinsic strain to optimize catalytic reactivity, which was confirmed experimentally on Pd(110) nanosheets for the oxygen reduction and hydrogen evolution reactions, with activity enhancements that were more than an order of magnitude greater than those of their nanoparticle counterparts., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Development and implementation of rapid antimicrobial susceptibility testing is critical for guiding patient care and improving clinical outcomes, especially in cases of sepsis. One approach to reduce the time-to-answer for antimicrobial susceptibility is monitoring the inhibition of DNA production, as differences in DNA concentrations are more quickly impacted compared to optical density changes in traditional antimicrobial susceptibility testing. Here, we use real-time PCR to rapidly determine antimicrobial susceptibility after short incubations with antibiotic. Application of this assay to a collection of 144 isolates in mock blood culture, covering medically relevant pathogens displaying high rates of resistance, provided susceptibility data in under 4 hours. This assay provided categorical agreement with a reference method in 96.3% of cases across all species. Sequencing of a subset of PCR amplicons showed accurate genus level identification. Overall, implementation of this method could provide accurate susceptibility results with a reduced time-to-answer for a number of medically relevant bacteria commonly isolated from blood culture., Competing Interests: The authors have declared that no competing interests exist.

Antibiotic resistant bacterial infections are a significant problem in the healthcare setting, in many cases requiring the rapid administration of appropriate and effective antibiotic therapy. Diagnostic assays capable of quickly and accurately determining the pathogen resistance profile are therefore crucial to initiate or modify care. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) is a standard method for species identification in many clinical microbiology laboratories and is well positioned to be applied towards antimicrobial susceptibility testing. One recently reported approach utilizes semi-quantitative MALDI-TOF MS for growth rate analysis to provide a resistance profile independent of resistance mechanism. This method was previously successfully applied to Gram-negative pathogens and mycobacteria; here, we evaluated this method with the Gram-positive pathogen Staphylococcus aureus. Specifically, we used 35 strains of S. aureus and four antibiotics to optimize and test the assay, resulting in an overall accuracy rate of 95%. Application of the optimized assay also successfully determined susceptibility from mock blood cultures, allowing both species identification and resistance determination for all four antibiotics within 3 hours of blood culture positivity.

The atomic simulation environment (ASE) is a software package written in the Python programming language with the aim of setting up, steering, and analyzing atomistic simulations. In ASE, tasks are fully scripted in Python. The powerful syntax of Python combined with the NumPy array library make it possible to perform very complex simulation tasks. For example, a sequence of calculations may be performed with the use of a simple 'for-loop' construction. Calculations of energy, forces, stresses and other quantities are performed through interfaces to many external electronic structure codes or force fields using a uniform interface. On top of this calculator interface, ASE provides modules for performing many standard simulation tasks such as structure optimization, molecular dynamics, handling of constraints and performing nudged elastic band calculations.

Ribosomally synthesized and post-translationally modified peptide (RiPP) natural products are attractive for genome-driven discovery and re-engineering, but limitations in bioinformatic methods and exponentially increasing genomic data make large-scale mining of RiPP data difficult. We report RODEO (Rapid ORF Description and Evaluation Online), which combines hidden-Markov-model-based analysis, heuristic scoring, and machine learning to identify biosynthetic gene clusters and predict RiPP precursor peptides. We initially focused on lasso peptides, which display intriguing physicochemical properties and bioactivities, but their hypervariability renders them challenging prospects for automated mining. Our approach yielded the most comprehensive mapping to date of lasso peptide space, revealing >1,300 compounds. We characterized the structures and bioactivities of six lasso peptides, prioritized based on predicted structural novelty, including one with an unprecedented handcuff-like topology and another with a citrulline modification exceptionally rare among bacteria. These combined insights significantly expand the knowledge of lasso peptides and, more broadly, provide a framework for future genome-mining efforts.

Background: In July 2009, Arkansas began to annually fund $20 million for a statewide trauma system (TS). We studied injury deaths both pre-TS (2009) and post-TS (2013 to 2014), with attention to causes of preventive mortality, societal cost of those preventable mortality deaths, and benefit to tax payers of the lives saved., Study Design: A multi-specialty trauma-expert panel met and reviewed records of 672 decedents (290 pre-TS and 382 post-TS) who met standardized inclusion criteria, were judged potentially salvageable, and were selected by a proportional sampling of the roughly 2,500 annual trauma deaths. Deaths were adjudicated into sub-categories of nonpreventable and preventable causes. The value of lives lost was calculated for those lives potentially saved in the post-TS period., Results: Total preventable mortality was reduced from 30% of cases pre-TS to 16% of cases studied post-TS, a reduction of 14%. Extrapolating a 14% reduction of preventable mortality to the post-TS study period, using the same inclusion criteria of the post-TS, we calculate that 79 lives were saved in 2013 to 2014 due to the institution of a TS. Using a minimal standard estimate of $100,000 value for a life-year, a lifetime value of $2,365,000 per person was saved. This equates to an economic impact of the lives saved of almost $186 million annually, representing a 9-fold return on investment from the $20 million of annual state funding invested in the TS., Conclusions: The implementation of a TS in Arkansas during a 5-year period resulted in a reduction of the preventable death rate to 16% post-TS, and a 9-fold return on investment by the tax payer. Additional life-saving gains can be expected with ongoing financial support and additional system performance-improvement efforts., (Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Pediatric traumatic amputations are devastating injuries capable of causing permanent physical and psychological sequelae. Few epidemiologic reports exist for guidance of prevention strategies. The objective of this study is to review the recent trends in pediatric traumatic amputations using a national databank., Methods: A review of all pediatric (age, 0 to 17 y) amputee patients was performed using the National Trauma Data Bank from 2007 to 2011. Data including demographics, location of amputation, and mechanism of injury were analyzed., Results: In the analysis 2238 patients were identified. The majority of amputations occurred in the youngest (0 to 5 y) and oldest (15 to 17 y) age groups with a 3:1 male to female ratio. The most common amputation locations were finger (54%) and toe (20%). A caught between mechanism (16.3%) was most common overall followed by machinery, powered lawn mowers, motor vehicle collisions, firearms, and off-road vehicles. Males were statistically more likely to have an amputation and lawnmower injuries were statistically associated with lower extremity amputations in children 5 years old and below. Motor vehicle injuries were the most common cause of adolescent amputations. Firearm-related amputations occurred predominantly in adolescents, whereas off-road vehicle amputations occurred in all ages., Conclusions: Common trends in pediatric amputations are relatively unchanged over the last decade. Young children sustain more finger amputations from a caught between objects mechanism, whereas adolescents sustain serious amputations from higher energy mechanisms such as firearms-related and motor vehicle-related injuries. Lawnmower-related amputations continue to most significantly affect younger children despite increased public awareness. Improved prevention strategies targeting age and mechanism-related trends are necessary to prevent these costly and debilitating injuries., Level of Evidence: Level IV.

Natural products (NPs) serve important roles as drug candidates and as tools for chemical biology. However, traditional NP discovery, largely based on bioassay-guided approaches, is biased toward abundant compounds and rediscovery rates are high. Orthogonal methods to facilitate discovery of new NPs are thus needed, and herein we describe an isotope tag-based expansion of reactivity-based NP screening to address these shortcomings. Reactivity-based screening is a directed discovery approach in which a specific reactive handle on the NP is targeted by a chemoselective probe to enable its detection by mass spectrometry. In this study, we have developed an aminooxy-containing probe to guide the discovery of aldehyde- and ketone-containing NPs. To facilitate the detection of labeling events, the probe was dibrominated, imparting a unique isotopic signature to distinguish labeled metabolites from spectral noise. As a proof of concept, the probe was then utilized to screen a collection of bacterial extracts, leading to the identification of a new analogue of antipain, deimino-antipain. The bacterial producer of deimino-antipain was sequenced and the responsible biosynthetic gene cluster was identified by bioinformatic analysis and heterologous expression. These data reveal the previously undetermined genetic basis for a well-known family of aldehyde-containing, peptidic protease inhibitors, including antipain, chymostatin, leupeptin, elastatinal, and microbial alkaline protease inhibitor, which have been widely used for over 40 years., Competing Interests: The authors declare no competing financial interest.

Antibiotics are a cornerstone of modern medicine and have significantly reduced the burden of infectious diseases. However, commonly used broad-spectrum antibiotics can cause major collateral damage to the human microbiome, causing complications ranging from antibiotic-associated colitis to the rapid spread of resistance. Employing narrower spectrum antibiotics targeting specific pathogens may alleviate this predicament as well as provide additional tools to expand an antibiotic repertoire threatened by the inevitability of resistance. Improvements in clinical diagnosis will be required to effectively utilize pathogen-specific antibiotics and new molecular diagnostics are poised to fulfill this need. Here we review recent trends and the future prospects of deploying narrower spectrum antibiotics coupled with rapid diagnostics. Further, we discuss the theoretical advantages and limitations of this emerging approach to controlling bacterial infectious diseases.

Plantazolicin (PZN) is a ribosomally synthesized and post-translationally modified natural product from Bacillus methylotrophicus FZB42 and Bacillus pumilus . Extensive tailoring to twelve of the fourteen amino acid residues in the mature natural product endows PZN with not only a rigid, polyheterocyclic structure, but also antibacterial activity. Here we report a remarkably discriminatory activity of PZN toward Bacillus anthracis , which rivals a previously-described gamma (γ) phage lysis assay in distinguishing B. anthracis from other members of the Bacillus cereus group. We evaluate the underlying cause of this selective activity by measuring the RNA expression profile of PZN-treated B. anthracis , which revealed significant upregulation of genes within the cell envelope stress response. PZN depolarizes the B. anthracis membrane like other cell envelope-acting compounds but uniquely localizes to distinct foci within the envelope. Selection and whole-genome sequencing of PZN-resistant mutants of B. anthracis implicate a relationship between the action of PZN and cardiolipin (CL) within the membrane. Exogenous CL increases the potency of PZN in wild type B. anthracis and promotes the incorporation of fluorescently tagged PZN in the cell envelope. We propose that PZN localizes to and exacerbates structurally compromised regions of the bacterial membrane, which ultimately results in cell lysis.

The crystal structure and absolute configuration of the two new title nelfinavir analogs, C24H35ClN4O5, (I), and C27H39ClN4O5, (II), have been determined. Each of these mol-ecules exhibits a number of disordered moieties. There are intra-molecular N-H⋯O hydrogen bonds in both (I) and (II). In (I) it involves the two carboxamide groups, while in (II) it involves the N-tert-butyl carboxamide group and the 2-hydroxyl O atom. The inter-molecular hydrogen bonding in (I) (O-H⋯O and N-H⋯O) leads to two-dimensional sheets that extend parallel to the ac plane. The inter-molecular hydrogen bonding in (II) (O-H⋯O) leads to chains that extend parallel to the a axis.

Background: Streptolysin S (SLS) is a cytolytic virulence factor produced by the human pathogen Streptococcus pyogenes and other Streptococcus species. Related "SLS-like" toxins have been characterized in select strains of Clostridium and Listeria, with homologous clusters bioinformatically identified in a variety of other species. SLS is a member of the thiazole/oxazole-modified microcin (TOMM) family of natural products. The structure of SLS has yet to be deciphered and many questions remain regarding its structure-activity relationships., Results: In this work, we assessed the hemolytic activity of a series of C-terminally truncated SLS peptides expressed in SLS-deficient S. pyogenes. Our data indicate that while the N-terminal poly-heterocyclizable (NPH) region of SLS substantially contributes to its bioactivity, the variable C-terminal region of the toxin is largely dispensable. Through genome mining we identified additional SLS-like clusters in diverse Firmicutes, Spirochaetes and Actinobacteria. Among the Spirochaete clusters, naturally truncated SLS-like precursors were found in the genomes of three Lyme disease-causing Borrelia burgdorferi sensu lato (Bbsl) strains. Although unable to restore hemolysis in SLS-deficient S. pyogenes, a Bbsl SLS-like precursor peptide was converted to a cytolysin using purified SLS biosynthetic enzymes. A PCR-based screen demonstrated that SLS-like clusters are substantially more prevalent in Bbsl than inferred from publicly available genome sequences., Conclusions: The mutagenesis data described herein indicate that the minimal cytolytic unit of SLS encompasses the NPH region of the core peptide. Interestingly, this region is found in all characterized TOMM cytolysins, as well as the novel putative TOMM cytolysins we discovered. We propose that this conserved region represents the defining feature of the SLS-like TOMM family. We demonstrate the cytolytic potential of a Bbsl SLS-like precursor peptide, which has a core region of similar length to the SLS minimal cytolytic unit, when modified with purified SLS biosynthetic enzymes. As such, we speculate that some Borrelia have the potential to produce a TOMM cytolysin, although the biological significance of this finding remains to be determined. In addition to providing new insight into the structure-activity relationships of SLS, this study greatly expands the cytolysin group of TOMMs.

Streptolysin S (SLS) is a post-translationally modified peptide cytolysin that is produced by the human pathogen Streptococcus pyogenes. SLS belongs to a large family of azole-containing natural products that are biosynthesized via an evolutionarily conserved pathway. SLS is an important virulence factor during S. pyogenes infections, but despite an extensive history of study, further investigations are needed to clarify several steps of its biosynthesis. To this end, chemical inhibitors of SLS biosynthesis would be valuable tools to interrogate the various maturation steps of both SLS and biosynthetically related natural products. Such chemical inhibitors could also potentially serve as antivirulence therapeutics, which in theory may alleviate the spread of antibiotic resistance. In this work, we demonstrate that FDA-approved HIV protease inhibitors, especially nelfinavir, block a key proteolytic processing step during SLS production. This inhibition was demonstrated in live S. pyogenes cells and through in vitro protease inhibition assays. A panel of 57 nelfinavir analogs was synthesized, leading to a series of compounds with improved anti-SLS activity while illuminating structure-activity relationships. Nelfinavir was also found to inhibit the maturation of other azole-containing natural products, namely those involved in listeriolysin S, clostridiolysin S, and plantazolicin production. The use of nelfinavir analogs as inhibitors of SLS production has allowed us to begin examining the proteolysis event in SLS maturation and will aid in further investigations of the biosynthesis of SLS and related natural products.

Objective: To discover if renal ultrasound (RUS) can be utilized as the primary follow-up imaging modality in the management of blunt renal injuries in children and adolescents., Methods: We initiated a protocol utilizing RUS reevaluations for children and adolescents treated for blunt renal injuries. Patients following this protocol (Post) had initial computerized tomography (CT) with RUS reevaluation at day 2 and 2 weeks. We retrospectively compared this group to a 2-year cohort treated between 2007 and 2009 (Pre)., Results: In our study, 28 Post protocol patients were retrospectively compared with 22 Pre cohort patients. No significant differences were observed in age, length of stay (LOS), injury severity score (ISS), and utilization of CT reevaluation. Follow-up reevaluation was obtained in 13 Pre patients versus 21 Post patients (p = 0.231). No patients had any evidence of long-term complications in either cohort., Conclusion: Our results suggest that RUS can be utilized as the primary surveillance imaging modality in the management of blunt renal injuries in children and adolescents. The lack of benefit of usage of RUS demonstrated in the acute post-injury surveillance period calls into question the benefit of RUS immediately following the blunt trauma., (Copyright © 2014 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Background: Previous studies have found racial and socioeconomic status bias in the way clinicians screen for and detect child abuse in patients presenting to the emergency department. We hypothesized that implementing a guideline for screening would attenuate this bias., Methods: An algorithm for child abuse screening in patients younger than 1 year presenting with fractures was developed for a pediatric trauma center emergency department. Data were collected 1.5 years before and after implementation of the algorithm to investigate implementation success. Data were compared before and after the implementation of the algorithm using χ and univariate logistic regression analysis., Results: The characteristics of patients with fractures were similar before and after the algorithm implementation. Implementation of the algorithm was related to a significant increase in algorithm required screenings: skeletal survey (p < 0.001), urinalysis (p < 0.001), and transaminase levels (p < 0.001). The racial composition of those screened did not change after the implementation of the protocol. Children with government-subsidized or no insurance were more likely to be screened for child abuse via skeletal survey before the algorithm implementation compared with those with private insurance (odds ratio, 2.7; 95% confidence interval, 1.2-6.0; p = 0.017). This relationship did not exist after the algorithm implementation (odds ratio, 1.2; 95% confidence interval, 0.56-2.46; p = 0.66). Final determination of child abuse was related to insurance status both before and after the algorithm implementation., Conclusion: A child abuse screening algorithm was successfully implemented in an urban trauma center. After implementation, screening was no longer associated with socioeconomic status of the patient's family, although final determination of child abuse still was. Additional research is needed to determine utility of unbiased screening on patient outcomes., Level of Evidence: Therapeutic study, level IV.

A 16-year-old adolescent boy sustained traumatic bronchopleural fistula, refractory to conventional management, which was treated successfully with differential lung ventilation and extracorporeal membrane oxygenation support. This case highlights a novel approach for managing traumatic bronchopleural fistula in children., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Unintentional injury is the leading cause of death for children in the United States. An association between parental alcohol use and the frequency and severity of childhood injuries has been found; however, research is limited. The purpose of this study was to (1) describe demographics, child safety behaviors, and parental risky behaviors for a pediatric trauma patient population and (2) assess the relationship between positive screen results for risky drinking in parents and demographic and child safety behaviors., Methods: Data were collected from a sample of parents of a child younger than 15 years who was admitted to an urban children's hospital for treatment for an unintentional injury. Data were analyzed using descriptive statistics, bivariate analyses, and logistic regression., Results: A total of 926 parents of 693 patients were included in this study. Of the families who completed the survey, 37.1% (n = 257) had at least one parent screening positive for risky alcohol use. When looking at patients who ride bicycles, a little more than half (55.1%) were reported as consistently using a helmet. Results showed that inconsistent helmet use was associated with a higher likelihood of at least one parent screening positive for risky drinking (odds ratio, 1.58; 95% confidence interval, 1.06-2.36; p ≤ 0.05)., Conclusion: Helmet use is a known prevention method of head injuries resulting from bicycle crashes. However, improvements need to be made on how to disseminate this information to parents and how to locate and intervene with the parents who have children that are at an increased risk of injury and injury recidivism. Using screening and brief intervention programs may assist in locating and reducing the potential of recurring visits by at-risk patients such as those in this sample who had at least one parent screening positive for risky drinking., Level of Evidence: Prognostic study, level III.

Background and Objective: Alcohol use by adolescents is widespread and is connected to a number of negative health and social outcomes. Adolescents receiving emergent care for injuries are often linked with risky use of alcohol. The trauma system has widely adopted the use of screening, brief intervention, and referral to treatment (SBIRT) for preventing alcohol-related injury recidivism and other negative outcomes. The purpose of this article is to review the evidence around SBIRT with adolescent patients in acute care settings., Methods: This article reviews 7 randomized controlled trials evaluating risky drinking interventions among adolescent patients in acute care settings. All studies took place in the emergency departments of level I trauma centers., Results: Four of the 7 studies reviewed demonstrated a significant intervention effect; however, no one intervention reduced both alcohol consumption and alcohol-related consequences. Two of these 4 studies only included patients ages 18 and older. Subgroup analyses with adolescents engaged in risky alcohol-related behaviors, conducted in 2 of the studies, showed significant intervention effects. Five studies showed positive consumption and/or consequences for all study participants regardless of condition, suggesting that an emergent injury and/or the screening process may have a protective effect., Conclusions: Based on existing evidence, it is not clear whether SBIRT is an effective approach to risky alcohol use among adolescent patients in acute care. Additional research is needed around interventions and implementation.

A fluorescent nucleobase analogue, 7-aminoquinazoline-2,4-(1H,3H)-dione, is incorporated into a DNA oligonucleotide and senses mismatched pairing by displaying G-specific fluorescence enhancement.

Objective: The aim of this study was to characterize the human cytokine response to Texas crotaline envenomation before and after antivenom administration., Methods: This study enrolled crotaline bite victims presenting to a regional trauma center and children's hospital from March to November 2007 and age-matched unbitten controls. Blood spot cards were obtained from bite victims at presentation and at 1 and 6 hours after antivenom administration. One control sample was drawn from each of the age-matched controls selected from urgent care patients presenting for minor complaints. Samples were delivered to a laboratory using a proprietary method for quantitative evaluation of a large number of biomarkers in parallel with bead-based multiplex immunoassays., Results: After obtaining informed consent, 14 crotaline bite victims (age range, 5-85 years; median age, 45 years; 50% female) (Snakebite Severity Score, 2-7; median, 3) and 14 age-matched controls were enrolled. There were 7 copperhead (Agkistrodon contortrix) bites, 4 rattlesnake (probably Western Diamondback Crotalus atrox) bites, 2 cottonmouth (Agkistrodon piscivorus) bites, and 1 bite from a snake that was not identified by the victim. In t tests, the means in the presentation samples for apolipoprotein A-I (Apo A-I), Apo C3, interleukin 4 (IL-4), myeloperoxidase, plasminogen activator inhibitor 1 (PAI-1), epidermal growth factor, and regulated upon activation, normal t-cell expressed and secreted were significantly lower and Apo H was significantly higher in the bite patients than in the controls. In the 1-hour sample, α(1)-antitrypsin, Apo A-I, Apo C3, eotaxin, IL-4, myeloperoxidase, and PAI-1 levels were lower and prostatic acid phosphatase and cancer antigen 125 levels were higher in the bite patients than in the controls. And in the 6-hour sample, α(1)-antitrypsin, Apo A-I, Apo C3, endothelin-1, IL-4, macrophage inflammatory protein 1β, myeloperoxidase, and epidermal growth factor levels were lower and Apo H level was higher in the bite patients than in controls (all P values < .05)., Conclusions: Crotaline venom produces a broad cytokine response in human bite victims. In particular, IL-4, myeloperoxidase, and Apo A-I and C3 levels remain altered despite antivenom therapy, whereas PAI-1 and regulated upon activation, normal t-cell expressed and secreted levels seem to normalize after antivenin as other markers are affected. Understanding this profile and further study of the markers identified might lead to improved therapies and better prognostic indicators., (Copyright © 2010 Elsevier Inc. All rights reserved.)

A new fluorescent ribonucleoside analogue, containing 5-aminoquinazoline-2,4(1H,3H)-dione, acts as a Forster resonance energy transfer acceptor for tryptophan (R(0) = 22 A) and displays visible emission (440 nm). As tryptophan is frequently found at or near the recognition domains of RNA binding proteins, this FRET pair facilitates the study of RNA binding to native proteins and peptides, which is demonstrated here for the HIV-1 Rev association with the Rev Response Element (RRE).

Objective: To perform polymerase chain reaction (PCR) analysis on paraffin-embedded myocardium from dogs with dilated cardiomyopathy (DCM) and dogs with myocarditis to screen for canine parvovirus, adenovirus types 1 and 2, and herpesvirus., Sample Population: Myocardial specimens from 18 dogs with an antemortem diagnosis of DCM and 9 dogs with a histopathologic diagnosis of myocarditis were evaluated., Procedure: Paraffin-embedded myocardial specimens were screened for viral genome by PCR analysis. Positive-control specimens were developed from cell cultures as well as paraffin-embedded tissue specimens from dogs with clinical and histopathologic diagnoses of viral infection with canine parvovirus, adenovirus types 1 and 2, and herpesvirus. The histologic characteristics of all myocardial specimens were classified regarding extent, location, and type of inflammation and fibrosis., Results: Canine adenovirus type 1 was amplified from 1 specimen from a dog with DCM. Canine parvovirus, adenovirus type 2, and herpesvirus were not amplified from any myocardial specimens. Histologic analysis of specimens from dogs with DCM revealed variable amounts of fibrosis; myocardial inflammation was observed in 1 affected dog. Histopathologic analysis of specimens from dogs with myocarditis disclosed variable degrees of inflammation and fibrosis., Conclusions and Clinical Relevance: Viral agents canine parvovirus, adenovirus types 1 and 2, and herpesvirus are not commonly associated with DCM or active myocarditis in dogs. Additional studies evaluating for nucleic acid from viruses that less commonly affect dogs or different types of infectious agents may be warranted to gain insight into the cause of DCM and myocarditis in dogs.

Incessant supraventricular tachyarrhythmias are known to result in myocardial dysfunction indistinguishable from idiopathic dilated cardiomyopathy by current testing methods. This tachycardia-induced cardiomyopathy (TICM), however, is uniquely reversible with adequate rhythm control. Two dogs were presented to The Ohio State University for incessant supraventricular tachycardia (SVT) and echocardiographic signs of dilated cardiomyopathy, later proven to be TICM. A 3rd dog presented for frequent paroxysms of SVT and syncope had echocardiographic signs of mild myocardial systolic dysfunction. All 3 dogs had inadequate rhythm control with multiple antiarrhythmic agents, and 1 dog suffered from recurrent left-sided congestive heart failure. Generalized cardiomegaly was found in 1 dog and left-sided dilatation without concurrent right-sided enlargement in 1 dog. Mild-to-severe left ventricular systolic dysfunction was confirmed echocardiographically in all dogs. A total of 4 atrioventricular accessory pathways (APs) were found during invasive electrophysiologic studies in these 3 dogs. All APs were successfully ablated with radiofrequency energy delivered through a thermistor-tipped catheter. Elimination of AP conduction, and thus orthodromic atrioventricular reciprocating tachycardia, resulted in resolution of all clinical and echocardiographic evidence of TICM in these dogs. This result confirms that the cardiomyopathy was, in fact, reversible TICM. All cardiovascular medications were discontinued, and no complications occurred during a 15-25-month follow-up period.

Allergy and/or contraindications for theophylline and adrenergic drugs can be a life-threatening problem for patients with respiratory failure resulting from status asthmaticus. Mucous plugs and secretions in smaller bronchi can further complicate the problem. A patient in status astmaticus complicated by mucous impaction is described in whom pulmonary lavage was performed through a flexible fiberoptic bronchoscope using a solution containing 250 ml normal saline, 30 ml 20% acetylcysteine, 0.5 ml Bronkosol and 125 mgm Solu-Medrol. Lavage was done twice at 24-hour intervals; extubation was accomplished within 48 hours after first lavage. This treatment resulted in remarkable improvement and proved to be life saving. The result suggests that this procedure is a useful therapeutic method and can be life saving in selected patients with respiratory failure.