High output power, single mode, and TEM00 operation of a multiple gain chip VECSEL using a twisted-mode configuration

A vertical external cavity surface emitting laser (VECSEL) has been developed for a sodium guide star application. Stable single frequency operation with 21 W of output power near 1178 nm with multiple gain elements while lasing in the TEM₀₀ mode has been achieved. Higher output power results in multimode lasing. For the sodium guide star application, the 1178 nm can be frequency doubled to 589 nm. The power scaling approach used involves using multiple gain mirrors in a folded standing wave cavity. This is the first demonstration of a high power single frequency VECSEL using a twisted-mode configuration and multiple gain mirrors located at the cavity folds.

Development and verification of the signal to noise ratio for a layer of turbulence in a multi-layer atmosphere

Wide-field image correction in systems that look through the atmosphere generally requires a tomographic reconstruction of the turbulence volume to compensate for anisoplanatism. The reconstruction is conditioned by estimating the turbulence volume as a profile of thin homogeneous layers. We present the signal to noise ratio (SNR) of a layer, which quantifies how difficult a single layer of homogeneous turbulence is to detect with wavefront slope measurements. The signal is the sum of wavefront tip and tilt variances at the signal layer, and the noise is the sum of wavefront tip and tilt auto-correlations given the aperture shape and projected aperture separations at all non-signal layers. An analytic expression for layer SNR is found for Kolmogorov and von Kármán turbulence models, then verified with a Monte Carlo simulation. We show that the Kolmogorov layer SNR is a function of only layer Fried length, the spatio-angular sampling of the system, and normalized aperture separation at the layer. In addition to these parameters, the von Kármán layer SNR also depends on aperture size, and layer inner and outer scales. Due to the infinite outer scale, layers of Kolmogorov turbulence tend to have lower SNR than von Kármán layers. We conclude that the layer SNR is a statistically valid performance metric to be used when designing, simulating, operating, and quantifying the performance of any system that measures properties of layers of turbulence in the atmosphere from slope data.

CNSC-08. TUMOUR-INFILTRATED CORTEX PARTICIPATES IN LARGE-SCALE COGNITIVE CIRCUITS

In neurosurgery, tumour-infiltrated cortex is generally assumed to be non-functional. While prior studies have suggested integration of tumour-infiltrated tissue in relatively local circuits responsible for language and motor function, it is unknown whether such tissue can participate in distributed networks important for higher-order cognitive abilities like executive function. We tested the hypothesis that diffuse low-grade gliomas integrate into large-scale cognitive circuits using intracranial electrocorticography and resting-state functional magnetic resonance imaging of four patients. To identify brain areas recruited for executive function, electrocorticography recordings were acquired from tumour-infiltrated tissue under three conditions: i) baseline (rest), ii) simple counting (1-20; “easy”), and iii) switch counting (1-a-2-b-3-c etc.; “hard”). In each patient, we observed significant task-based high gamma power modulations in tumour-infiltrated cortex in response to increasing cognitive effort (p < 0.05), implying preserved functionality of neoplastic tissue for complex tasks. Additionally, tumour locations corresponding to task-responsive electrodes exhibited functional connectivity patterns that significantly co-localised with canonical brain networks implicated in higher-order cognitive processing (p < 0.05). Finally, dorsal attention network connectivity in tumour-infiltrated cortex correlated with high gamma power elevations during increased cognitive demand (χ 2(1) = 5.14; p = 0.023), establishing a concordance between both techniques. Overall, this study contributes convergent evidence that tumour-infiltrated cortex can participate in large-scale neurocognitive circuits, prompting a reconsideration of traditional notions of neoplastic brain tissue.

Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales^1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare⁴ in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet⁵, plasma instabilities^6,7 or orbital motion in an accretion disc^7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. ⁹). BL Lac, the prototype of a subclass of blazars¹⁰, is powered by a 1.7 × 10⁸ M_Sun (ref. ¹¹) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. ¹²)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities⁶ near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

CRISPR-Cas9 editing of the arginine-vasopressin V1a receptor produces paradoxical changes in social behavior in Syrian hamsters

Studies from a variety of species indicate that arginine–vasopressin (AVP) and its V1a receptor (Avpr1a) play a critical role in the regulation of a range of social behaviors by their actions in the social behavior neural network. To further investigate the role of AVPRs in social behavior, we performed CRISPR-Cas9–mediated editing at the Avpr1a gene via pronuclear microinjections in Syrian hamsters (Mesocricetus auratus), a species used extensively in behavioral neuroendocrinology because they produce a rich suite of social behaviors. Using this germ-line gene-editing approach, we generated a stable line of hamsters with a frame-shift mutation in the Avpr1a gene resulting in the null expression of functional Avpr1as. Avpr1a knockout (KO) hamsters exhibited a complete lack of Avpr1a-specific autoradiographic binding throughout the brain, behavioral insensitivity to centrally administered AVP, and no pressor response to a peripherally injected Avpr1a-specific agonist, thus confirming the absence of functional Avpr1as in the brain and periphery. Contradictory to expectations, Avpr1a KO hamsters exhibited substantially higher levels of conspecific social communication (i.e., odor-stimulated flank marking) than their wild-type (WT) littermates. Furthermore, sex differences in aggression were absent, as both male and female KOs exhibited more aggression toward same-sex conspecifics than did their WT littermates. Taken together, these data emphasize the importance of comparative studies employing gene-editing approaches and suggest the startling possibility that Avpr1a-specific modulation of the social behavior neural network may be more inhibitory than permissive.

NIMG-31. PROPOSED ORIGINS AND PATHWAYS OF DIFFUSE GLIOMAS REVEALED BY LESION COVARIANCE NETWORKS

Diffuse gliomas have been hypothesized to originate from neural stem cells in the subventricular zone and develop along previously healthy brain networks. Here, we evaluated these hypotheses by mapping independent sources of glioma localization and determining their relationships with neurogenic niches, genetic markers, and large-scale connectivity networks. Using lesion data from a total of 410 patients with high- and low-grade glioma, we identified – and replicated in an independent sample – three lesion covariance networks (LCNs), which reflect clusters of frequent glioma localization. These three LCNs overlapped with the anterior, posterior, and inferior horns of the lateral ventricles respectively, extending into the frontal, parietal, and temporal cortices. The first LCN, which overlapped with the anterior horn, was associated with low-grade, IDH-mutated/1p19q-codeleted tumors, as well as a neural transcriptomic signature and improved overall survival. Each LCN significantly coincided with multiple structural and functional connectivity networks, with LCN1 bearing an especially strong relationship with brain connectivity, consistent with its neural transcriptomic profile. Finally, we identified subcortical, periventricular structures with functional connectivity patterns to the cortex that significantly matched each LCN. These results build upon prior reports of glioma growth along white matter pathways, as well as evidence for the coordination of glioma stem cell proliferation by neuronal activity. Cumulatively, our findings support a model wherein periventricular brain connectivity guides glioma development from the subventricular zone into distributed brain regions.

Building sustainable research and data tools and partnerships for a healthy city for all

 

Vancouver is located in a temperate rain forest surrounded by mountains and water. Indigenous communities, including the Nations whose homelands the city occupies, have recognized that the abundance of this place can build healthy communities for many generations. But contemporary Vancouver is not a healthy city for all. Since 2014, Vancouver has adopted a Healthy City Strategy, a master social sustainability plan to address inequities in the social determinants of health at a population scale. This includes a number of population health targets and indicators. However, implementation has been slow, with substantive integration of health into policy not yet achieved. With support from the Partnership for Healthy Cities, we have translated the Healthy City Strategy's indicators into an online dashboard, including disaggregated local data. In addition to public accountability, this tool enables data to be a platform for aligning city policy, action and investment toward common health outcomes. In parallel, we are also piloting more community-generated approaches to health data and indicators, with a focus on co-creating health indicators with Indigenous communities. Preliminary results have shown improvement in collaboration across city departments, leading to increased focus on upstream, preventive work. The dashboard is enabling frameworks for funding and working with the social service sector toward common health goals. Engagement efforts have shown the continued importance of a holistic strategy for health that is co-created with community knowledge and priorities. These interventions must be sustained and integrated into ongoing work. The technical work of developing the dashboard contributes to city-wide efforts toward data monitoring and reporting. Data has shown to be an important tool for beginning conversations, but sharing data about health inequities experienced by communities must be matched with an ongoing commitment to engagement and co-creation.

Key messages

Population health data can be leveraged through interactive tools to better integrate and align city policies, plans and investments to address the social determinants of health. Engaging and co-creating policy with communities supports upstream, preventive action on health inequities.

OS14.4.A The Neuroplastic Potential of the Human Brain before and After Glioma Surgery: Towards “Interventional Neurorehabilitation

INTRODUCTION

The human brain is a highly neuroplastic ‘complex’ network: it self-organises without a hard blueprint, adapts to evolving circumstances, and can withstand insults. However, similar to other naturally occurring networks, brain networks can only endure a finite amount of damage before cognitive processes are affected. In this study, we first sought to establish the brain networks governing domain-general cognition (DGC) in healthy individuals across the lifespan. We then sought to map, track, and potentially rehabilitate networks governing DGC through connectomics and non-invasive brain stimulation (NIBS) when damaged by low-grade gliomas (LGG) and surgical oncology.

METHODS

Using MRI and cognitive data from n=629 individuals (aged 18–88, Female= 51%), we assessed the structural, functional, and topological relevance of the spatially-distributed multiple-demand (MD) system for DGC. Next, in n=17 patients undergoing glioma surgery, we longitudinally acquired connectomic and cognitive data at multiple time points: pre-surgery and post-surgery Day 1, Month 3, Month 12. In an independent cohort of n=34 patients, we sought to establish the safety profile for “interventional neurorehabilitation”: connectome-driven NIBS in the acute post-operative period to accelerate cognitive recovery.

RESULTS

In healthy individuals, the MD system across multiple scales of biological organisation was positively associated with higher-order cognition (Catell’s fluid intelligence). In our patients, pre-operative LGG infiltration into the structural MD system was negatively associated with the number of long-term cognitive deficits, suggesting a functional reorganisation. Mixed-effects modelling demonstrated the resilience of the functional MD system to infiltration and resection, while the early post-operative period was critical for effective neurorehabilitation. Graph analyses revealed increased perioperative modularity can distinguish patients with long-term cognitive improvements at one-year follow-up. Finally, NIBS within two weeks post-craniotomy had a 90% (n=31/34) recruitment rate into the trial. There were no seizures or serious complications due to NIBS in this patient population. Transient headaches and tingling were reported in a minority of patients.

CONCLUSION

For the first time, we elucidate long-term cognitive and network trajectories following LGG surgery while establishing a positive safety-profile for NIBS in the acute post-operative period. We argue that “mesoscale” brain mapping serves as a robust biomarker for intervention-related plasticity for future clinical trials. While we performed these experiments in the context of neurosurgery, connectomics and NIBS could be adopted across diverse neuro-oncological care pathways (i.e. chemotherapy/radiation).

Strong host-specific selection and over-dominance characterize arbuscular mycorrhizal fungal root colonizers of coastal sand dune plants of the Mediterranean region

Sand dunes of the Mediterranean region constitute drought-stressed, low-fertility ecosystems. Arbuscular mycorrhizal fungi (AMF) are regarded as key components of their biota, that contribute to plant host adaptation and fitness. However, AMF community assembly rules in the roots of the psammophilous plants of coastal sand dunes have not been investigated. We studied the root colonizing AMF communities of four characteristic native plants of eastern Mediterranean coastal foredunes, in nine locations in Greece. Host specificity (plant identity) was the major driver of AMF community assembly in the plant roots, while geographical distance between locations was not related to differences in the AMF communities. Additionally, colonizer AMF communities were characterized by overdominance of a single OTU which was remarkably host-specific among locations. Wider dissimilarity in AMF communities was observed in small and disturbed (SD) sites compared to large and undisturbed (LU) sites, a trait that may be attributed to relaxed environmental filtering and facilitated AMF dispersal/immigration in SD sites from surrounding habitats. Overall, our results indicate that the assembly of root-colonizing AMF communities in the eastern Mediterranean sand dunes is characterized by strong biotic filtering (host identity), suggesting that co-adaptation processes may be more pronounced than previously proposed, under extreme environmental conditions.

Pyramid and Shack-Hartmann hybrid wave-front sensor

An ideal wave-front sensor (WFS) for an adaptive optics system prioritizes three properties: high sensitivity, wide dynamic range, and a linear relationship between the actual and estimated wave fronts. WFSs currently in operation can claim superiority in only two of these properties. For example, the Shack-Hartmann WFS (SHWFS) has a linear response and remains effective under large aberrations, but its sensitivity to low spatial frequencies is limited [Proc. SPIE5490, 1177 (2004)PSISDG0277-786X10.1117/12.550786]. The pyramid WFS (PyWFS) [J. Mod. Opt.43, 289 (1996)JMOPEW0950-034010.1080/09500349608232742] can also be operated in a linear control system [Opt. Express14, 11925 (2006)OPEXFF1094-408710.1364/OE.14.011925] and offers excellent sensitivity when used with an unresolved beacon but saturates quickly in the presence of large aberrations. The dynamic range can be extended by modulating the beacon about the pyramid prism tip, but at the expense of its sensitivity. This Letter describes a hybrid WFS (HyWFS) that combines the SHWFS and PyWFS, capturing the desirable features of both. The optical design of the HyWFS mimics the appearance of an unmodulated PyWFS with a lenslet array in the reimaged pupil planes. Spot patterns in the style of a SHWFS are formed in all pupil images. Wave-front estimates are calculated from the HyWFS's output using both conventional PyWFS and SHWFS reconstruction methods. A cross-over algorithm chooses between the two estimates to retain high sensitivity to low aberration and a robust capture range.

Wavelength frame multiplication for reflectometry at long-pulse neutron sources

The European Spallation Source (ESS), which is under construction in Lund (Sweden), will be the next leading neutron facility with an unprecedented brilliance and novel long-pulse time structure. A long-pulse source not only provides a high time-average flux but also opens the possibility to tune the resolution by using pulse shaping choppers. Thus, an instrument can readily be operated in either a high flux or a high resolution mode. Several of the shorter instruments at the ESS will employ Wavelength Frame Multiplication (WFM) in order to enable a sufficient resolution while offering a continuous and broad wavelength range. A test beamline was operated until the end of 2019 at the research reactor in Berlin to test components and methods, including WFM, in order to prepare the new facility for the operation of neutron instruments and successful first science. We herein demonstrate the implementation of WFM for reflectometry. By selecting a short pulse mode under the same geometrical configuration, we compare and discuss the results for two reference samples. The reported experiments not only serve to prove the reliability of the WFM approach but also, for the first time, demonstrate the full instrument control, data acquisition and data reduction chain that will be implemented at the ESS.

NIMG-13. GENETIC, CELLULAR, AND CONNECTOMIC CHARACTERIZATION OF THE ADULT HUMAN BRAIN REGIONS COMMONLY PLAGUED BY GLIOMA

For decades, it has been known that gliomas follow a nonrandom spatial distribution, appearing more often in some brain regions (e.g. the insula) compared to others (e.g. the occipital lobe). A better understanding of the glioma localization patterns could lend clues to the origins of these types of tumors, and consequently inform treatment targets. Following hypotheses derived from prior research into neuropsychiatric disease and cancer, gliomas may be expected to localize to brain regions characterized by functional hubness, stem-like cells, and transcription of genetic drivers of gliomagenesis. We combined neuroimaging data from 335 adult patients with high- and low-grade glioma to form a replicable tumor frequency map. Using this map, we demonstrate that glioma frequency is elevated in association cortex and correlated with multiple graph-theoretical metrics of high functional connectedness. Brain regions populated with putative cells-of-origin for glioma, neural stem cells and oligodendrocyte precursor cells, exhibited a high glioma frequency. Leveraging a human brain atlas of post-mortem gene expression, we found that gliomas were localized to brain regions enriched with expression of genes associated with chromatin organization and synaptic signaling. A set of glioma proto-oncogenes was enriched among the transcriptomic correlates of glioma distribution. Finally, a regression model incorporating connectomic, cellular, and genetic factors explained 58% of the variance in glioma frequency. These results add to previous literature reporting the vulnerability of hub regions to neurological disease, as well as provide support for cancer stem cell theories of glioma. Our findings illustrate how factors of diverse scale, from genetic to connectomic, can independently influence the anatomic localization of brain dysfunction.

Laboratory biomarkers associated with COVID-19 severity and management

The heterogeneous disease course of COVID-19 is unpredictable, ranging from mild self-limiting symptoms to cytokine storms, acute respiratory distress syndrome (ARDS), multi-organ failure and death. Identification of high-risk cases will enable appropriate intervention and escalation. This study investigates the routine laboratory tests and cytokines implicated in COVID-19 for their potential application as biomarkers of disease severity, respiratory failure and need of higher-level care.

From analysis of 203 samples, CRP, IL-6, IL-10 and LDH were most strongly correlated with the WHO ordinal scale of illness severity, the fraction of inspired oxygen delivery, radiological evidence of ARDS and level of respiratory support (p ≤ 0.001). IL-6 levels of ≥3.27 pg/ml provide a sensitivity of 0.87 and specificity of 0.64 for a requirement of ventilation, and a CRP of ≥37 mg/l of 0.91 and 0.66.

Reliable stratification of high-risk cases has significant implications on patient triage, resource management and potentially the initiation of novel therapies in severe patients.

Multidisciplinary shock team is associated with improved outcomes in patients undergoing ECPR

OBJECTIVES

Veno-arterial extracorporeal membrane oxygenation (VA ECMO) has been increasingly used in cardiopulmonary resuscitation (ECPR) in select patients. Few centers have published their experience or outcomes with ECPR. The aim of our study was to evaluate outcomes of adult patients in cardiac arrest placed on VA ECMO in the catheterization laboratory.

METHODS

We performed a retrospective analysis of adult patients in refractory cardiac arrest who underwent ECPR at the Minneapolis Heart Institute (MHI) at Abbott Northwestern Hospital from January 2012 to December 2017. Relevant data were obtained from electronic medical records, including arrest to ECMO flow time, total ECMO support time, and outcomes.

RESULTS

Twenty-six adult patients underwent ECPR at the study site during the defined time period. Seven patients (27%) sustained cardiac arrest out of hospital, 19 patients arrested in-hospital with eight of those occurring in the catheterization laboratory. Seventeen (65%) patients had initial rhythm of ventricular fibrillation or tachycardia (VF/VT). All patients underwent mechanical CPR with LUCAS device. Overall 30 day and 6 month survival was 69%. Median time from arrest to ECMO flow was 46 mins (21,68) vs 61 mins (36,71) in survivors and non-survivors, respectively. Sixteen of 18 survivors discharged with a CPC score of 1 or 2.

CONCLUSIONS

We demonstrate that adult patients in cardiac arrest initiated on VA ECMO in the cardiac catheterization laboratory and cared for by a multidisciplinary shock team in the critical care unit have superior long-term survival and functionally favorable neurologic recovery when compared to current literature.

Characterization of orally efficacious influenza drug with high resistance barrier in ferrets and human airway epithelia

Influenza viruses constitute a major health threat and economic burden globally, frequently exacerbated by preexisting or rapidly emerging resistance to antiviral therapeutics. To address the unmet need of improved influenza therapy, we have created EIDD-2801, an isopropylester prodrug of the ribonucleoside analog N ⁴-hydroxycytidine (NHC, EIDD-1931) that has shown broad anti-influenza virus activity in cultured cells and mice. Pharmacokinetic profiling demonstrated that EIDD-2801 was orally bioavailable in ferrets and nonhuman primates. Therapeutic oral dosing of influenza virus-infected ferrets reduced group pandemic 1 and group 2 seasonal influenza A shed virus load by multiple orders of magnitude and alleviated fever, airway epithelium histopathology, and inflammation, whereas postexposure prophylactic dosing was sterilizing. Deep sequencing highlighted lethal viral mutagenesis as the underlying mechanism of activity and revealed a prohibitive barrier to the development of viral resistance. Inhibitory concentrations were low nanomolar against influenza A and B viruses in disease-relevant well-differentiated human air-liquid interface airway epithelia. Correlating antiviral efficacy and cytotoxicity thresholds with pharmacokinetic profiles in human airway epithelium models revealed a therapeutic window >1713 and established dosing parameters required for efficacious human therapy. These data recommend EIDD-2801 as a clinical candidate with high potential for monotherapy of seasonal and pandemic influenza virus infections. Our results inform EIDD-2801 clinical trial design and drug exposure targets.

Noncanonical NF-κB signaling is suppressed through the negative regulation of the essential kinase NIK and attenuation is associated with eosinophilic esophagitis pathogenesis

Eosinophilic esophagitis (EoE) is an allergic disease of the esophagus driven by T cell and eosinophil responses to dietary allergens, resulting in chronic mucosal inflammation. NF-κB signaling is a master regulator of gene transcription and drives diverse biological processes of relevance to EoE. NF-κB activation occurs through either canonical or noncanonical pathways. In general, there is a relative paucity of knowledge regarding noncanonical NF-κB regulation and signaling. Previously, we have shown that mice with hyperactive noncanonical NF-κB signaling are more susceptible to Th1/Th17 mediated experimental colitis and cancer. Conversely, mice with attenuated noncanonical NF-κB signaling spontaneously develop EoE. The objective of our current study is to translate these findings from mouse models to human patients. Clinical specimens were collected from a cohort of 16 EoE patients and representative controls. Gene expression and protein analysis revealed a significant decrease in p52, RelB, and chemokines specifically associated with noncanonical NF-κB signaling correlated with EoE. However, we also identified a significant change in several mediators that should increase noncanonical NF-κB signaling upstream of the essential kinase NIK. Thus, our data suggest a disconnect between pathway activation and p52/RelB mediated gene transcription, with NIK functioning as a key regulatory target. Further analysis identified 6 regulatory proteins that target NIK in EoE patient specimens and robustly attenuate downstream noncanonical NF-κB signaling. Together, these data demonstrate the significance of this understudied pathway in human EoE and identify potential targets for future therapeutic strategies.

Quantitative efficacy paradigms of the influenza clinical drug candidate EIDD-2801 in the ferret model

Seasonal influenza viruses cause major morbidity and mortality worldwide, threatening in particular older adults and the immunocompromised. Two classes of influenza therapeutics dominate current disease management, but both are compromised by pre-existing or rapidly emerging viral resistance. We have recently reported a novel ribonucleoside analog clinical candidate, EIDD-2801, that combines potent antiviral efficacy in ferrets and human airway epithelium cultures with a high barrier against viral escape. In this study, we established fundamental EIDD-2801 efficacy paradigms against pandemic and seasonal influenza A virus (IAV) strains in ferrets that can be used to inform exposure targets and treatment regimens. Based on reduction of shed virus titers, alleviation of clinical signs, and lowered virus burden in upper and lower respiratory tract tissues, lowest efficacious oral dose concentrations of EIDD-2801, given twice daily, were 2.3 and 7 mg/kg of body weight against seasonal and pandemic IAVs, respectively. The latest opportunity for initiation of efficacious treatment was 36 hours after infection of ferrets. Administered in 12-hour intervals, three 7 mg/kg doses of EIDD-2801 were sufficient for maximal therapeutic benefit against a pandemic IAV and significantly shortened the time to resolution of clinical signs. Ferrets infected with pandemic IAV and treated following the minimally efficacious EIDD-2801 regimen demonstrated significantly less shed virus and inflammatory cellular infiltrates in nasal lavages, but mounted a robust humoral antiviral response after recovery that was indistinguishable from that of vehicle-treated animals. These results provide an experimental basis in a human disease-relevant influenza animal model for clinical testing of EIDD-2801.

A216 EXAMINING THE EFFECTS OF GLYPHOSATE EXPOSURE ON THE GUT BACTERIOME AND INFLAMMATION IN A MURINE MODEL OF COLITIS

Background

Canada has the highest incidence of inflammatory bowel disease in the world, which is expected to rise unabated for the next 30 years. Coincidently, Canada is one of the most prolific users of the herbicide glyphosate (tradename Roundup®), with over 25 million kilograms purchased annually. Previous studies examining the effects of glyphosate on the gut bacteriome have used high levels of glyphosate (ranging from 2.5mg – 25mg/kg bw/day) and have yielded conflicting results. Our goal is to examine the effects of dietary levels of glyphosate on the gut microbiome and inflammation in an animal model of colitis. Two environmentally relevant doses were explored: (1) the acceptable daily intake currently set by the Environmental Protection Agency (EPA) (1.75mg/kg bw/day) and (2) North American dose, calculated by a registered dietician using literature values of glyphosate found within food products (0.1mg/kg bw/day.)

Aims

1) To determine if glyphosate exposure influences intestinal permeability 2) To determine if glyphosate exposure influences intestinal inflammation 3) To determine if glyphosate exposure influences colitis onset and severity. We hypothesized that exposure to glyphosate leads to bacterial dysbiosis, increased intestinal permeability and increased severity of colitis in Mucin 2 deficient mice (Muc2-/-mice).

Methods

Upon weaning, Muc2-/- mice were exposed to glyphosate through their drinking water. Animals were monitored weekly for clinical signs of colitis, including rectal prolapse. Following 12-week glyphosate exposure, intestinal permeability was measured using the FITC-dextran permeability assay. Intestinal inflammation was measured using qPCR and markers relevant to our animal model including REGIIIγ, RELM-β and CLEC-2.

Results

Exposure to glyphosate at physiologically relevant levels does not increase intestinal permeability in Muc2-/-mice, with all groups showing equal levels of FITC-dextran present within their serum. Animals exposed to the EPA dose of glyphosate exhibited earlier onset of colitis symptoms with animals receiving higher clinical scores and displaying an increased rate of rectal prolapse. Animals exposed to the EPA dose also showed a significant increase in CLEC-2 expression. CLEC-2 is a C-type lectin-like receptor expressed by immune cells and platelets and has been implicated in tumor metastasis. Additionally, overexpression of CLEC-2 has been shown to promote pathogen adherence to mammalian cells.

Conclusions

Exposure to glyphosate at levels deemed safe by the EPA increases colitis onset and severity in Muc2-/- deficient animals. Additionally, EPA level glyphosate exposure upregulates CLEC-2 expression which may have implications for tumor development and increased enteropathogenic infections.

Funding Agencies

CCCCrowdfunding, NSERC

Narrow-linewidth operation of folded 1178nm VECSEL with twisted-mode cavity

A vertical external-cavity surface-emitting laser (VECSEL) with a twisted-mode configuration is demonstrated. This architecture is particularly advantageous for power scaling of single-frequency VECSELs employing multiple gain mirrors in folded cavities. In such a configuration, some of the gain mirrors are inherently at the fold, and the lasing spectrum becomes unstable. This is caused by four waves interfering, destabilizing the standing wave pattern at the quantum wells. We show that the lasing spectrum can be narrowed by employing a twisted-mode configuration, which stabilizes the standing-wave pattern at the gain mirror. Furthermore, single-frequency output of more than 10 W at 1178 nm is demonstrated for a VECSEL employing two gain mirrors in a standing-wave cavity. In comparison, the output power for operation with one gain mirror only was 7.4 W when operating in single frequency. The choice of wavelength for the work reported in this paper is motivated by the opportunity to demonstrate compact VECSEL-based guide star lasers for adaptive optics via frequency doubling to the sodium D₂ resonance at 589 nm.

A semi-arid river in distress: Contributing factors and recovery solutions for three imperiled freshwater mussels (Family Unionidae) endemic to the Rio Grande basin in North America

Freshwater resources in arid and semi-arid regions are in extreme demand, which creates conflicts between needs of humans and aquatic ecosystems. The Rio Grande basin in the southwestern United States and northern Mexico exemplifies this issue, as much of its aquatic biodiversity is in peril as a result of human activities. Unionid mussels have been disproportionately impacted, though the specific factors responsible for their decline remain largely unknown. This is problematic because the Rio Grande basin harbors one federally endangered unionid mussel (Popenaias popeii, Texas Hornshell) plus two other mussel species (Potamilus metnecktayi, Salina Mucket; and Truncilla cognata, Mexican Fawnsfoot), which are also being considered for listing under the U.S. Endangered Species Act. To date, surveys for these species have not corrected for variability in detection so current range estimates may be inaccurate. Using single occupancy-modeling to estimate detection and occupancy at 115 sites along ~800 river kilometers of the Rio Grande in Texas, we found that detection probabilities were relatively high, indicating that our survey design was efficient. In contrast, the estimated occupancy was low, indicating that our focal species were likely rare within the Rio Grande drainage. In general, the predicted occupancy of our focal species was low throughout their respective ranges, indicating possible range declines. A comparison of currently occupied ranges to presumptive ranges underscores this point. The best-approximating models indicated that occupancy was influenced by habitat, water quantity and quality, and proximity to large-scale human activities, such as dams and major urban centers. We also discuss a series of conservation options that may not only improve the long-term prognosis of our focal species but also other aquatic taxa.

Misidentification of sex for Lampsilis teres, Yellow Sandshell, and its implications for mussel conservation and wildlife management

Correct identification of sex is an important component of wildlife management because changes in sex ratios can affect population viability. Identification of sex often relies on external morphology, which can be biased by intermediate or nondistinctive morphotypes and observer experience. For unionid mussels, research has demonstrated that species misidentification is common but less attention has been given to the reliability of sex identification. To evaluate whether this is an issue, we surveyed 117 researchers on their ability to correctly identify sex of Lampsilis teres (Yellow Sandshell), a wide ranging, sexually dimorphic species. Personal background information of each observer was analyzed to identify factors that may contribute to misidentification of sex. We found that median misidentification rates were ~20% across males and females and that observers falsely identified the number of female specimens more often (~23%) than males (~10%). Misidentification rates were partially explained by geographic region of prior mussel experience and where observers learned how to identify mussels, but there remained substantial variation among observers after controlling for these factors. We also used three morphometric methods (traditional, geometric, and Fourier) to investigate whether sex could be more correctly identified statistically and found that misidentification rates for the geometric and Fourier methods (which characterize shape) were less than 5% (on average 7% and 2% for females and males, respectively). Our results show that misidentification of sex is likely common for mussels if based solely on external morphology, which raises general questions, regardless of taxonomic group, about its reliability for conservation efforts.

Methodological shortcomings in the literature evaluating the role and applications of 3D training for surgical trainees

AIM

There has been an increased interest in the use of three-dimensional (3D) technology in surgical training. We wish to appraise the methodological rigor applied to evaluating the role and applications of 3D technology in surgical training, in particular, on the validity of these models and assessment methods in simulated surgical training.

METHODS

Literature search was performed using MEDLINE with the following terms: "3D"; "surgery"; and "training". Only studies evaluating the role of 3D technology in surgical training were eligible for inclusion and assessed for the level of evidence, validity of the simulation model, and assessment method used.

RESULTS

A total of 93 studies were analyzed, and majority of reviewed articles focused on 3D displays (36) and 3D printing (35). Most of these studies were case series, the most common assessment was subjective (69), with objective assessment used by 57 studies. Very few studies provided evidence for validity of the model or the assessment methods used.

CONCLUSIONS

3D technology has a great potential in simulated surgical training. However, the validity of this technology and strong evidence for its beneficial effects in surgical training is lacking. Further work on validation of 3D technology and assessment tools is needed.

Monitoring Theileria orientalis (Ikeda)-associated bovine anaemia in affected cattle over time

The aim of the study was to observe changes in haematocrit (HCT) over time in a New Zealand South Island dairy herd affected by an outbreak of Theileria-associated bovine anaemia (TABA; Ikeda). A secondary aim was to relate individual cow HCTs to the amount of Theileria orientalis Ikeda DNA present in the blood, as measured by cycle threshold values, using a quantitative PCR (qPCR). Over a 6 month period, blood samples from 19 randomly selected cattle were monitored from a herd of 600 dairy cows. The sampling interval was approximately fortnightly for the first six weeks, followed by sampling at between four and six week intervals. At the initial report of the outbreak, two from six cattle were anaemic (HCT<0.25L/L). Blood collected from 14 cattle 11 days later showed that 57% (95% CI 33-77%) of the cattle sampled were anaemic. Of the 19 cattle that went on to be monitored, 12 (63% 95% CI=41-81%) developed anaemia at some point during the period of monitoring. One of the anaemic animals did not meet the case definition for TABA Ikeda. For individual cattle, the average number of days between when cattle were first detected as anaemic and when HCT returned to normal was 53days (median=47 days, range=6-92 days). At the point of notification the amount of T. orientalis Ikeda DNA in the blood of the six cattle tested was low (Cq median=36), but 11days later the amount of DNA in blood of 14 additional cows tested was relatively high (Cq median=24). Levels of all 19 cows monitored continued to remain moderately high through the period of testing (Cq median=29). This was despite a general improvement in the HCT of affected cattle. In four of the 15 cattle positive to T. orientalis Ikeda where blood fractions (plasma and whole blood) were tested, it appeared that T. orientalis Ikeda (as measured by qPCR) dropped more rapidly in plasma fractions than in whole blood at the point that HCT started to return to normal levels. Despite the assumption that tick populations were low in the Canterbury region of the South Island the impact of TABA (proportion of herd affected and the average period that animals remained anaemic) on the case herd was still relatively high.

Budesonide Oral Suspension Improves Symptomatic, Endoscopic, and Histologic Parameters Compared With Placebo in Patients With Eosinophilic Esophagitis

BACKGROUND & AIMS

Pharmacologic treatment of eosinophilic esophagitis (EoE) is limited to off-label use of corticosteroids not optimized for esophageal delivery. We performed a randomized, controlled phase 2 trial to assess the ability of budesonide oral suspension (BOS), a novel muco-adherent topical steroid formulation, to reduce symptoms and esophageal eosinophilia in adolescents and adults with EoE.

METHODS

In this multicenter, randomized, double-blind, placebo-controlled, parallel-group trial, 93 EoE patients between the ages of 11 and 40 years with dysphagia and active esophageal eosinophilia were randomized to receive either BOS 2 mg or placebo twice daily for 12 weeks. Co-primary outcomes were change in Dysphagia Symptom Questionnaire (DSQ) score from baseline, and proportion of patients with a histologic response (≤6 eosinophils/high-power field) after treatment. Endoscopic severity scores and safety parameters were assessed.

RESULTS

At baseline, mean DSQ scores were 29.3 and 29.0, and mean peak eosinophil counts were 156 and 130 per hpf in the BOS and placebo groups, respectively. After treatment, DSQ scores were 15.0 and 21.5, and mean peak eosinophil counts were 39 and 113 per high-power field, respectively (P < .05 for all). For BOS vs placebo, change in DSQ score was -14.3 vs -7.5 (P = .0096), histologic response rates were 39% vs 3% (P < .0001), and change in endoscopic severity score was -3.8 vs 0.4 (P < .0001). Adverse events were similar between groups.

CONCLUSIONS

Treatment with BOS was well tolerated in adolescent and young adult patients with EoE and resulted in improvement in symptomatic, endoscopic, and histologic parameters using validated outcome instruments. ClinicalTrials.gov ID NCT01642212.

Quantitative pre-clinical screening of therapeutics for joint diseases using contrast enhanced micro-computed tomography

OBJECTIVE

The development of effective therapies for cartilage protection has been limited by a lack of efficient quantitative cartilage imaging modalities in pre-clinical in vivo models. Our objectives were two-fold: first, to validate a new contrast-enhanced 3D imaging analysis technique, equilibrium partitioning of an ionic contrast agent-micro computed tomography (EPIC-μCT), in a rat medial meniscal transection (MMT) osteoarthritis (OA) model; and second, to quantitatively assess the sensitivity of EPIC-μCT to detect the effects of matrix metalloproteinase inhibitor (MMPi) therapy on cartilage degeneration.

METHODS

Rats underwent MMT surgery and tissues were harvested at 1, 2, and 3 weeks post-surgery or rats received an MMPi or vehicle treatment and tissues harvested 3 weeks post-surgery. Parameters of disease progression were evaluated using histopathology and EPIC-μCT. Correlations and power analyses were performed to compare the techniques.

RESULTS

EPIC-μCT was shown to provide simultaneous 3D quantification of multiple parameters, including cartilage degeneration and osteophyte formation. In MMT animals treated with MMPi, OA progression was attenuated, as measured by 3D parameters such as lesion volume and osteophyte size. A post-hoc power analysis showed that 3D parameters for EPIC-μCT were more sensitive than 2D parameters requiring fewer animals to detect a therapeutic effect of MMPi. 2D parameters were comparable between EPIC-μCT and histopathology.

CONCLUSION

This study demonstrated that EPIC-μCT has high sensitivity to provide 3D structural and compositional measurements of cartilage and bone in the joint. EPIC-μCT can be used in combination with histology to provide a comprehensive analysis to screen new potential therapies.

Atmospheric tomography for artificial satellite observations with a single guide star

Estimation of wavefront errors in three dimensions is required to mitigate isoplanatic errors when using adaptive optics or numerical restoration algorithms to recover high-resolution images from blurred data taken through atmospheric turbulence. Present techniques rely on multiple beacons, either natural stars or laser guide stars, to probe the atmospheric aberration along different lines of sight, followed by tomographic projection of the measurements. In this Letter, we show that a three-dimensional estimate of the wavefront aberration can be recovered from measurements by a single guide star in the case where the aberration is stratified, provided that the telescope tracks across the sky with nonuniform angular velocity. This is generally the case for observations of artificial Earth-orbiting satellites, and the new method is likely to find application in ground-based telescopes used for space situational awareness.

Serum tocilizumab trough concentration can be used to monitor systemic IL-6 receptor blockade in patients with rheumatoid arthritis: a prospective observational cohort study

OBJECTIVES

To investigate the pharmacokinetics (PK) and dynamics of tocilizumab (TCZ) in daily practice.

METHOD

An observational study of 66 consecutive RA patients treated with TCZ 8 mg/kg once every 4 weeks intravenously, monitored for 24 weeks. Spearman's rank test was used to investigate the correlation between TCZ concentration and C-reactive protein (CRP). Clinical improvement was assessed at week 24 using the Disease Activity Score in 28 joints (DAS28) compared to baseline, and its relationship with TCZ concentration was investigated using linear regression analyses. TCZ trough concentrations and anti-drug antibodies were measured using an enzyme-linked immunosorbent assay (ELISA) and antigen binding test, respectively.

RESULTS

At baseline, 26 patients (39.4%) had a CRP level above 10 mg/L with a median (interquartile range, IQR) of 37.7 (21.9-49.7) mg/L. A TCZ concentration above 1 mg/L was sufficient to normalize CRP levels. Spearman's rank test showed a correlation coefficient of -0.460 (p < 0.0001). The TCZ concentration varied widely, with concentrations < 1 mg/L in 17-31% of patients, depending on the time point of measurement. Anti-TCZ antibodies were detected in one sample. Linear regression analyses showed a coefficient of 0.080 with a 95% confidence interval (CI) of 0.039-0.113 (p < 0.001) for the association between TCZ concentration and ΔDAS28. No confounders were identified.

CONCLUSIONS

The TCZ standard regimen results in a wide variety of serum TCZ trough concentrations; this is mostly due to target binding and to a lesser extent to immunogenicity. The majority of patients obtained TCZ concentrations > 1 mg/L, which is sufficient for CRP normalization. Therefore, dose taper strategies might be possible in a substantial proportion of patients.

High-resolution speckle imaging through strong atmospheric turbulence

We demonstrate that high-resolution imaging through strong atmospheric turbulence can be achieved by acquiring data with a system that captures short exposure ("speckle") images using a range of aperture sizes and then using a bootstrap multi-frame blind deconvolution restoration process that starts with the smallest aperture data. Our results suggest a potential paradigm shift in how we image through atmospheric turbulence. No longer should image acquisition and post processing be treated as two independent processes: they should be considered as intimately related.

The First Record of Aedes (Hulecoeteomyia) japonicus (Diptera: Culicidae) and Its Establishment in Western Canada

The potential disease-carrying mosquito, Aedes japonicus (Theobald) (Diptera: Culicidae), was identified among larvae collected in suburban Vancouver, BC, in July 2014, and over 200 were found at the same site in February 2015 where it presumably had overwintered in the egg stage. In late May 2015, a female was captured taking a bloodmeal 13 km east of the larval site. This population and those in the Washington and Oregon states are clearly disjunct from those in eastern North America, and their origin, probably from one or more different introductions from Asia, is discussed. Key characters of those in British Columbia are examined and match the description of subspecies japonicus, presumably like the others in North America.

High prevalence of bla OXA-23 in Acinetobacter spp. and detection of bla NDM-1 in A. soli in Cuba: report from National Surveillance Program (2010-2012)

As a first national surveillance of Acinetobacter in Cuba, a total of 500 Acinetobacter spp. isolates recovered from 30 hospitals between 2010 and 2012 were studied. Acinetobacter baumannii–calcoaceticus complex accounted for 96.4% of all the Acinetobacter isolates, while other species were detected at low frequency (A. junii 1.6%, A. lwoffii 1%, A. haemolyticus 0.8%, A. soli 0.2%). Resistance rates of isolates were 34–61% to third-generation cephalosporins, 49–50% to β-lactams/inhibitor combinations, 42–47% to aminoglycosides, 42–44% to carbapenems and 55% to ciprofloxacin. However, resistance rates to colistin, doxycycline, tetracycline and rifampin were less than 5%. Among carbapenem-resistant isolates, 75% harboured different bla_OXA genes (OXA-23, 73%; OXA-24, 18%; OXA-58, 3%). The bla_NDM-1 gene was identified in an A. soli strain, of which the species was confirmed by sequence analysis of 16S rRNA gene, rpoB, rpoB–rpoC and rpoL–rpoB intergenic spacer regions and gyrB. The sequences of bla_NDM-1 and its surrounding genes were identical to those reported for plasmids of A. baumannii and A. lwoffi strains. This is the first report of bla_NDM-1 in A. soli, together with a high prevalence of OXA-23 carbapenemase for carbapenem resistance in Acinetobacter spp. in Cuba.

The influence of paediatric HIV infection on circulating B cell subsets and CXCR5(+) T helper cells

Antiretroviral therapy (ART) only partially restores HIV-induced alterations in lymphocyte populations. We assessed B and T cell phenotypes in a cohort of children from a single centre in the United Kingdom with perinatally acquired HIV compared to healthy controls. The majority of HIV infected children (44 of 56) were on fully suppressive combination ART. Children with perinatally acquired HIV had significantly lower memory B and CD4(+) CD45RO(+) CXCR5(+) [follicular T helper cell (Tfh)-like] T cell percentages. Detectable viraemia was associated with higher CD21(-) (activated and exhausted/tissue-like memory) B cells. A greater proportion of life spent on suppressive ART was associated with higher memory B cell percentages. These results suggest that early and sustained suppressive ART may preserve B and T cell phenotypes in perinatally acquired HIV and limit deficits in humoral immunity. A lower proportion of circulating Tfh-like cells in HIV infected children appears to be independent of HIV treatment history and ongoing HIV viraemia and warrants further investigation.

I12: the Joint Engineering, Environment and Processing (JEEP) beamline at Diamond Light Source

I12 is the Joint Engineering, Environmental and Processing (JEEP) beamline, constructed during Phase II of the Diamond Light Source. I12 is located on a short (5 m) straight section of the Diamond storage ring and uses a 4.2 T superconducting wiggler to provide polychromatic and monochromatic X-rays in the energy range 50-150 keV. The beam energy enables good penetration through large or dense samples, combined with a large beam size (1 mrad horizontally × 0.3 mrad vertically). The beam characteristics permit the study of materials and processes inside environmental chambers without unacceptable attenuation of the beam and without the need to use sample sizes which are atypically small for the process under study. X-ray techniques available to users are radiography, tomography, energy-dispersive diffraction, monochromatic and white-beam two-dimensional diffraction/scattering and small-angle X-ray scattering. Since commencing operations in November 2009, I12 has established a broad user community in materials science and processing, chemical processing, biomedical engineering, civil engineering, environmental science, palaeontology and physics.

Nuclear waste viewed in a new light; a synchrotron study of uranium encapsulated in grout

How do you characterise the contents of a sealed nuclear waste package without breaking it open? This question is important when the contained corrosion products are potentially reactive with air and radioactive. Synchrotron X-rays have been used to perform micro-scale in-situ observation and characterisation of uranium encapsulated in grout; a simulation for a typical intermediate level waste storage packet. X-ray tomography and X-ray powder diffraction generated both qualitative and quantitative data from a grout-encapsulated uranium sample before, and after, deliberately constrained H2 corrosion. Tomographic reconstructions provided a means of assessing the extent, rates and character of the corrosion reactions by comparing the relative densities between the materials and the volume of reaction products. The oxidation of uranium in grout was found to follow the anoxic U+H2O oxidation regime, and the pore network within the grout was observed to influence the growth of uranium hydride sites across the metal surface. Powder diffraction analysis identified the corrosion products as UO2 and UH3, and permitted measurement of corrosion-induced strain. Together, X-ray tomography and diffraction provide means of accurately determining the types and extent of uranium corrosion occurring, thereby offering a future tool for isolating and studying the reactions occurring in real full-scale waste package systems.

Improved upper limits on the stochastic gravitational-wave background from 2009-2010 LIGO and Virgo data

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of Ω_{GW}(f)=Ω_{α}(f/f_{ref})^{α}, we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of α=0, we constrain the energy density of the stochastic background to be Ω_{GW}(f)<5.6×10^{-6}. For the 600-1000 Hz band, Ω_{GW}(f)<0.14(f/900  Hz)^{3}, a factor of 2.5 lower than the best previously reported upper limits. We find Ω_{GW}(f)<1.8×10^{-4} using a spectral index of zero for 170-600 Hz and Ω_{GW}(f)<1.0(f/1300  Hz)^{3} for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Search for gravitational waves associated with γ-ray bursts detected by the interplanetary network

We present the results of a search for gravitational waves associated with 223 γ-ray bursts (GRBs) detected by the InterPlanetary Network (IPN) in 2005-2010 during LIGO's fifth and sixth science runs and Virgo's first, second, and third science runs. The IPN satellites provide accurate times of the bursts and sky localizations that vary significantly from degree scale to hundreds of square degrees. We search for both a well-modeled binary coalescence signal, the favored progenitor model for short GRBs, and for generic, unmodeled gravitational wave bursts. Both searches use the event time and sky localization to improve the gravitational wave search sensitivity as compared to corresponding all-time, all-sky searches. We find no evidence of a gravitational wave signal associated with any of the IPN GRBs in the sample, nor do we find evidence for a population of weak gravitational wave signals associated with the GRBs. For all IPN-detected GRBs, for which a sufficient duration of quality gravitational wave data are available, we place lower bounds on the distance to the source in accordance with an optimistic assumption of gravitational wave emission energy of 10(-2)M⊙c(2) at 150 Hz, and find a median of 13 Mpc. For the 27 short-hard GRBs we place 90% confidence exclusion distances to two source models: a binary neutron star coalescence, with a median distance of 12 Mpc, or the coalescence of a neutron star and black hole, with a median distance of 22 Mpc. Finally, we combine this search with previously published results to provide a population statement for GRB searches in first-generation LIGO and Virgo gravitational wave detectors and a resulting examination of prospects for the advanced gravitational wave detectors.

Emergence of Klebsiella pneumoniae clinical isolates producing KPC-2 carbapenemase in Cuba

The emergence of Klebsiella pneumoniae producing carbapenemase (KPC) has now become a global concern. As a part of a nationwide multicentre surveillance study in Cuba, three K. pneumoniae clinical isolates resistant to carbapenems were detected for a 1-month period (September to October 2011). PCR and sequence analysis revealed that the three strains harboured bla KPC-2. They showed resistance or intermediate susceptibility to expanded-spectrum cephalosporins, other β-lactams, a β-lactam/β-lactamase inhibitor combination, and gentamicin. Two strains were susceptible only to colistin, whereas the other strain showing colistin resistance was susceptible to fluoroquinolones. These bla KPC -2-positive K. pneumoniae strains were classified into ST1271 (CC29), a novel clone harbouring bla KPC -2, and were revealed to be genetically identical by PCR-based DNA fingerprinting. The three patients infected with the KPC-producing K. pneumoniae had common risk factors, and had no overseas travel experience outside Cuba, suggesting local acquisition of the resistant pathogen. This is the first report of a KPC-producing K. pneumoniae in Cuba. Although detection of KPC in Enterobacteriaceae is still rare in Cuba, our finding indicated that KPC-producing bacteria are a global concern and highlighted the need to identify these microorganisms in clinical laboratories.

Elective day-case laparoscopic cholecystectomy: a formal assessment of the need for outpatient follow-up

INTRODUCTION

Elective laparoscopic cholecystectomy (LC) is performed routinely as day-case surgery. Most hospital trusts have a policy of no routine postoperative outpatient follow-up although there are no formal guidelines on this. The aim of this retrospective study was to identify the incidence of complications, the degree of symptom resolution and patient satisfaction with a view to formally appraising the need for outpatient follow-up.

METHODS

Patients who underwent LC in the period between February 2011 and June 2012 were contacted retrospectively by telephone. A standardised questionnaire was used to ascertain the incidence of surgical site infection (SSI), other complications, symptom resolution and patient satisfaction.

RESULTS

A total of 211 responses were collected. The rate of SSI was 7.6% (n=16), with the only specific risk factor being smoking (p=0.027). All other complications had a combined incidence of 7% (n=15). There was complete resolution of symptoms in 64% of patients. Of the 36% of patients with residual symptoms, 45% described abdominal discomfort or pain, 41% described reflux symptoms and 14% complained of diarrhoea. Patient satisfaction was very high (96%), yet 33% of patients visited their general practitioner postoperatively in relation to their surgery.

CONCLUSIONS

Patients are highly satisfied with elective day-case LC. However, SSI is not uncommon, occurring in 1 in 13 patients. Although the majority of patients experience complete symptom resolution, a significant proportion do not. In our experience, routine outpatient follow-up is not required. Nevertheless, the lack of formal follow-up may prove a missed learning opportunity, potentially resulting in inappropriate patient selection for surgery.

Elective day-case laparoscopic cholecystectomy: a formal assessment of the need for outpatient follow-up

Introduction

Elective laparoscopic cholecystectomy (LC) is performed routinely as day-case surgery. Most hospital trusts have a policy of no routine postoperative outpatient follow-up although there are no formal guidelines on this. The aim of this retrospective study was to identify the incidence of complications, the degree of symptom resolution and patient satisfaction with a view to formally appraising the need for outpatient follow-up.

Methods

Patients who underwent LC in the period between February 2011 and June 2012 were contacted retrospectively by telephone. A standardised questionnaire was used to ascertain the incidence of surgical site infection (SSI), other complications, symptom resolution and patient satisfaction.

Results

A total of 211 responses were collected. The rate of SSI was 7.6% (n=16), with the only specific risk factor being smoking (p=0.027). All other complications had a combined incidence of 7% (n=15). There was complete resolution of symptoms in 64% of patients. Of the 36% of patients with residual symptoms, 45% described abdominal discomfort or pain, 41% described reflux symptoms and 14% complained of diarrhoea. Patient satisfaction was very high (96%), yet 33% of patients visited their general practitioner postoperatively in relation to their surgery.

Conclusions

Patients are highly satisfied with elective day-case LC. However, SSI is not uncommon, occurring in 1 in 13 patients. Although the majority of patients experience complete symptom resolution, a significant proportion do not. In our experience, routine outpatient follow-up is not required. Nevertheless, the lack of formal follow-up may prove a missed learning opportunity, potentially resulting in inappropriate patient selection for surgery.