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.

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.

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.

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.

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

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.

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.

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.

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.

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.

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.

Localized 3D analysis of cartilage composition and morphology in small animal models of joint degeneration

OBJECTIVE

Current histological scoring methods to evaluate efficacy of potential therapeutics for slowing or preventing joint degeneration are time-consuming and semi-quantitative in nature. Hence, there is a need to develop and standardize quantitative outcome measures to define sensitive metrics for studying potential therapeutics. The objectives of this study were to use equilibrium partitioning of an ionic contrast agent via Equilibrium Partitioning of an Ionic Contrast-Microcomputed tomography (EPIC-μCT) to quantitatively characterize morphological and compositional changes in the tibial articular cartilage in two distinct models of joint degeneration and define localized regions of interest to detect degenerative cartilage changes.

MATERIALS AND METHODS

The monosodium iodoacetate (MIA) and medial meniscal transection (MMT) rat models were used in this study. Three weeks post-surgery, tibiae were analyzed using EPIC-μCT and histology. EPIC-μCT allowed measurement of 3D morphological changes in cartilage thickness, volume and composition.

RESULTS

Extensive cartilage degeneration was observed throughout the joint in the MIA model after 3 weeks. In contrast, the MMT model showed more localized degeneration with regional thickening of the medial tibial plateau and a decrease in attenuation consistent with proteoglycan (PG) depletion. Focal lesions were also observed and 3D volume calculated as an additional outcome metric.

CONCLUSIONS

EPIC-μCT was used to quantitatively assess joint degeneration in two distinct preclinical models. The MMT model showed similar features to human Osteoarthritis (OA), including localized lesion formation and PG loss, while the MIA model displayed extensive cartilage degeneration throughout the joint. EPIC-μCT imaging provides a rapid and quantitative screening tool for preclinical evaluation of OA therapeutics.

Gastrointestinal parasites of coyotes (Canis latrans) in the metropolitan area of Calgary, Alberta, Canada

Disease ecology is a relevant but relatively unexplored subject of research in urban coyotes ( Canis latrans Say, 1823). In fact, this carnivore may play a role in the circulation of parasites that can have implications on the health of humans and domestic dogs, but can also be affected by pathogens transmitted from domestic reservoirs. To investigate the gastrointestinal parasites of urban coyotes in Calgary, Alberta, Canada, we analyzed 61 carcasses and 247 fecal samples collected within the metropolitan area, including city parks, in 2009–2010. We found nine parasite taxa: Toxascaris leonina (Linstow, 1902), Uncinaria stenocephala (Railliet, 1884), Ancylostoma caninum (Ercolani, 1859), Pterygodermatites affinis (Jägerskiöld, 1904), Trichuris vulpis (Froelich, 1789), Echinococcus multilocularis Leuckart, 1863, Taenia crassiceps (Zeder, 1800), genus Giardia Kunstler, 1882, and genus Cystoisospora Frenkel, 1977. Factors related to coyote ecology, habitat characteristics, and dog management likely influence the community of coyote parasites in an urban environment, and need to be taken into account to assess the actual role of this carnivore in the maintenance of parasites in the city landscape. Further research is needed to assess the current risk for transmission of potentially zoonotic parasites (e.g., E. multilocularis, T. crassiceps, Giardia sp.) among coyotes, dogs, and humans.

Gas insufflation of minimal preparation CT of the colon reduces false-positives

OBJECTIVES

Minimal preparation CT of the colon (MPCT colon) is used for investigation of suspected colorectal cancer in frail and/or elderly patients who would be expected to tolerate laxative bowel preparation poorly. Although it has good sensitivity for colorectal cancer it has a poor specificity. We wished to investigate whether distension of the colon with carbon dioxide alone would reduce the number of false-positives, but without making the test arduous or excessively uncomfortable.

METHODS

134 patients were recruited and underwent MPCT colon with gas insufflation and antispasmodics. Results were compared with a cohort of 134 patients undergoing standard protocol MPCT colon. The numbers of false-positives were compared, as was reader confidence. All trial patients were given a questionnaire documenting their experience.

RESULTS

The number of false-positives was 15% in the control group and 5% in the trial group; this difference was statistically significant, (p=0.01). Reader confidence was increased in the trial group. Patient tolerance was good, with 95% saying they would have the test again.

CONCLUSION

Use of gas insufflation and antispasmodics reduces the false-positives from 15% to 5% without adversely affecting patient tolerance.

Physical and chemical stability of Taxotere (docetaxel) one-vial (20 mg/ml) infusion solution following refrigerated storage

A one-vial formulation of the chemotherapy agent Taxotere(®) (docetaxel) is likely to be commercially available in some countries in 2010. Through control of two significant potential risk factors for crystallization-intervention into the infusion bag (by using a one-step technique) and temperature (by use of refrigerated storage)-it was postulated that the risk of precipitation would be reduced and the storage time of Taxotere(®) increased using the one-vial formulation versus the two-vial formulation. Furthermore, improved convenience and flexibility were anticipated as a result of the easier and quicker preparation associated with the one-vial formulation versus the two-vial formulation. The results of the physicochemical stability study presented here indicate that the one-vial formulation is indeed associated with reduced risk of precipitation of docetaxel. Moreover, refrigerated storage has been shown to extend the physical and chemical stability for up to seven days, versus 4 h for the currently approved two-vial formulation and 6 h for the one-vial formulation stored at room temperature. However, only physical and chemical stability have been assessed in this study.

Retrospective analysis of salvage percutaneous cryoablation of hepatocellular cancer (HCC) in liver

e15649

Background: We report our initial experience with percutaneous cryoablation of HCC in liver. Prior published series are limited. Methods: We treated 30 lesions in 23 patients (pts): Child-Pugh class A, 13 pts; B, 8 pts.; C, 2 pts Candidate pts had residual disease after intra-arterial chemotherapy. Probe placement (2.4 mm, Endocare) occurred under general anesthesia with restricted tidal volume to facilitate computer tomographic (CT) localization. An average 2.7 probes (range 1- 5) achieved an estimated margin of 0.5 cm visualizing the ice ball after two 10 min freeze cycles. Median follow-up was 342 days (range 30–947) Results: Tumors ranged from 1.3 to 5.8 cm. Three pts died within 30 days: 2 following intra-peritoneal hemorrhage despite control of bleeding and 1 from ischemic liver injury following a TIPSS for hydrothorax in a pt with refractory ascites. Two additional pts had hemorrhage with recovery. Risk of bleeding was associated with ascites (P = 0.013). One pt had cutaneous needle tract tumor seeding caused by needle repositioning prior to freezing. Survivors remained clinically stable at the 2–3 month follow-up. At the 2 month evaluation 29 lesions had no residual enhancement by CT. One lesion required a second cryoablation procedure.There were no recurrences in any target lesion (30–947 days). Thirteen pts are alive without recurrence of whom 6 had liver transplant with no (4) or < 5% (2) residual disease. Three pts have had recurrence in non-target liver and have died. Multiple tumors at baseline predicts for hepatic recurrence. Two pts have died from complications of cirrhosis, and 2 are lost to follow-up. Conclusions: Percutaneous cryoablation effectively manages selected hepatic HCC tumors. Cirrhotic pts with ascites have significant risk for hemorrhage. We recommend peri-procedure paracentesis and an immediate post-procedure CT.

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Intraoperative ultrasound versus mammographic needle localization for ductal carcinoma in situ

BACKGROUND

Ductal carcinoma in situ (DCIS) often requires some method of localization to achieve breast-conserving therapy. The purpose of this study was to compare the efficacy of intraoperative ultrasound versus mammographic needle localization (MNL) for partial mastectomy in DCIS.

MATERIALS AND METHODS

Data were collected from a Breast Cancer Surgery Database. All DCIS cases undergoing partial mastectomy (PM) were identified. Margin status, re-excision rates, and cost were determined for both groups.

RESULTS

A total of 155 patients undergoing PM for DCIS were identified from the database. In the 96 patients undergoing ultrasound-guided PM (Group 1), the positive margin rate was 10.4%, and close margins (<1 mm) were observed in 22.9% after initial surgery. There were 59 patients who underwent MNL (Group 2); the positive margin rate was 11.9%, and close margins were observed in 27.1%. The difference between positive and close margins in Group 1 versus Group 2 was not statistically significant. The rate of re-excision was 20.8% for Group 1 and 30.5% for Group 2, resulting in 1.23 and 1.37 operations per patient, respectively. The average cost of an intraoperative ultrasound at our institution was $933 and $1858 for MNL (excluding cost of radiologic interpretation), a difference of $925 per case.

CONCLUSION

Our study showed equivalent rates of positive margins and re-excision between intraoperative ultrasound and MNL when performing PM for nonpalpable DCIS. Considering the more invasive nature and increased cost of MNL, we consider surgeon-performed intraoperative ultrasound, when possible, the more cost-effective and practical procedure for patients with DCIS.

Outcomes of isolated tibial shaft fractures treated at level 1 trauma centres

BACKGROUND

Although most tibial shaft fractures are expected to heal within 24 weeks, the long-term effects of these injuries on patients in terms of self-reported health status, disability, and pain are largely unknown.

OBJECTIVES

To investigate the clinical and patient-reported outcomes of patients with isolated tibial shaft fractures treated at the two level 1 adult trauma centres in Victoria, Australia.

METHODS

Sixty patients with isolated tibial shaft fractures treated at the Royal Melbourne Hospital and the Alfred Hospital between August 2003 and August 2004 were identified via the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR). Patient-reported outcomes were prospectively measured 1 year post-injury using the 12-Item Short-Form Health Survey (SF-12) (also administered at baseline); the Work subscale of the Sickness Impact Profile; and a Numerical Rating Scale for pain. A priori defined clinical outcomes were also determined by retrospectively reviewing hospital medical records and X-rays.

RESULTS

Full weight-bearing status was achieved after a median inter quartile range (IQR) time of 14.0 (12.5-20.0) weeks, and the median (IQR) time to radiological union was 35.8 (23.3-51.6) weeks. Sixty percent of patients completed the SF-12 at both baseline and 12 months post-injury. Although there were no clear changes in mental health scores (median change=+1.0; IQR=-3.5 to 4.0; p=0.52), physical health scores were significantly reduced (median change=-3.0; IQR=-19.5 to 0.3; p=0.003). Additionally, 47% of patients reported work-related disability and 40% experienced persistent pain 1 year post-injury.

CONCLUSIONS

These results indicate that long-term physical disability remains a problem for many patients following tibial shaft fracture, and they should be considered when providing prognostic information to patients. Further research is required to identify the specific health problems experienced as well as the factors contributing to disability in order to inform post-fracture rehabilitation planning.

Transgenic mice overexpressing both amyloid beta-protein and perlecan in pancreatic acinar cells

Heparan sulfate proteoglycans such as perlecan are thought to facilitate amyloid fibril formation. Tg3695 mice overexpress perlecan core protein in many tissues including the brain and pancreas. Tg13592 mice overexpress the signal plus 99-amino acid carboxyl terminal sequences (C99) of amyloid beta-protein precursor in multiple tissues and develop amyloid deposits in the pancreas. To investigate a role of perlecan in beta-amyloidosis, we established doubly transgenic mice by crossing the two lines of transgenic mice. The expression levels of the two transgenes remained unchanged in the brain and pancreas and the doubly transgenic mice did not develop amyloid deposits in the brain up to 19-months of age. Amyloid load detected by thioflavine S in the pancreas of the doubly transgenic mice was not significantly different from that in the transgenic littermates expressing only C99. Amyloid load in the pancreas increased during aging. We found a positive correlation between the Abeta-immunoreactive (non-fibrillar and fibrillar) and thioflavine S-positive (fibrillar) Abeta deposits in the single (C99) but not doubly transgenic mice. Our results suggest that perlecan does not independently influence amyloid formation in the pancreas of the transgenic mice and that there may be other factors that may modulate amyloid formation together with perlecan.