Venous thromboembolism in patients with pancreatic adenocarcinoma: Disease burden and initiation of ambulatory thromboprophylaxis.

BACKGROUND/OBJECTIVES: Ambulatory thromboprophylaxis (AT) in patients with pancreatic adenocarcinoma (PAC) reduces venous thromboembolism (VTE) risk and is recommended for patients receiving systemic chemotherapy. We evaluated VTE rates, severity, timing, and risk factors in PAC patients as well as AT rates and initiation times. METHODS: Patients diagnosed with PAC were included. Data collected included patient demographics, medical history, PAC diagnosis, development of VTE, AT, and bleeding episodes. VTE was defined as a DVT or a PE. Patients were classified as receiving AT for VTE prevention if they received a prescription for outpatient anticoagulation. RESULTS: The cohort included 243 PAC patients. VTE occurred in 24 %. Overall, 52 % developing VTE were hospitalized and 5 % died as a result of the VTE. Of those who developed VTE 50 % were diagnosed within the first 2 months of PAC diagnosis. Univariate predictors of elevated VTE risk included an elevated Onkotev score, metastasis at diagnosis, male gender and not receiving AT. Multivariate predictors of elevated VTE risk included male gender (P = 0.014) and not receiving AT (P = 0.001). Overall, 30 % of patients received AT. The median time from diagnosis to initiation of AT was 43 days. Major bleeding occurred in 5.8 %. Patients receiving AT were not at a significantly increased risk of major bleeding (p = 0.5). Patients with intestinal tumor invasion were at significantly increased risk of major bleeding (P = 0.021). CONCLUSION: VTE risk is significant and morbid in PAC patients. AT rates are low, and initiation is often delayed. Therapeutic endoscopists diagnosing PAC may be helpful in AT initiation.

Exhaled Pneumocystis jirovecii output and detection of asymptomatic exhalation by facemask sampling in HIV-uninfected, immunocompromised patients.

BACKGROUND: Pneumocystis jirovecii pneumonia (PJP) transmission is poorly defined. Previous studies have sampled air of rooms occupied by HIV-infected patients with PJP, while natural and direct exhalations of HIV-uninfected subjects remain under-investigated. Here, clinical facemasks were used to examine and quantify potential P. jirovecii exhalations from HIV-uninfected patients with suspected PJP and to determine whether pathogen exhalation was definable clinically or radiologically. METHODS: Forty-five patients in Leicester (England), highly suspected of having PJP based on European Conference on Infections in Leukaemia (ECIL-5) guidelines, each wore one facemask carrying a gelatine/PVA sampling matrix for 1 h while respiring normally. Mask contamination with P. jirovecii was assessed using a modified quantitative polymerase chain reaction targeting mitochondrial large subunit (MtLSU). Radiological findings on chest X-ray (CXR) and computed tomography (CT) were graded and analysed for correlation with P. jirovecii signals alongside relevant clinical and laboratory findings. RESULTS: P. jirovecii was detected in seven of 20 patients diagnosed with PJP and three of 19 patients with suspected but undiagnosed PJP. The median captured signal was 8.59 × 104 MtLSU copies/mask (interquartile range (IQR) = 3.01 × 105-1.81 × 104). Blood ß-D-glucan test results correlated with the mask detection data (r = 0.65; P<0.0001) but other clinical indices and radiological features did not. Five of the 10 P. jirovecii-exhalers exhibited normal CXR with a median exhalation burden 1.28 × 105 copies/mask (IQR = 1.51 × 105-2.27 × 104). Two P. jirovecii-exhalers (7.64 × 104 copies/mask) were asymptomatic. CONCLUSION: P. jirovecii was exhaled sufficiently during normal respiration to be detectable in facemasks worn by HIV-uninfected patients. Neither clinical nor radiological features correlated with P. jirovecii exhalation.

Idiopathic subglottic stenosis in Saskatchewan Hutterite population.

BACKGROUND: By studying the odds of developing idiopathic subglottic stenosis in the isolated and genetically unique Hutterite population, this study sought to strengthen the hypothesis that an underlying genetic predisposition may exist for its development. METHODS: A retrospective chart review examined the medical records of all adult patients treated for idiopathic subglottic stenosis in Saskatchewan between 2008 and 2018. Cases were segregated into Hutterite and non-Hutterite. RESULTS: Four out of 36 cases of idiopathic subglottic stenosis occurred among Hutterites. The odds of a Hutterite developing idiopathic subglottic stenosis are 21.89 times higher than for non-Hutterites. Positive family history was only observed in the Hutterite population. CONCLUSION: The study strengthens the hypothesis that genetics may play a role in the aetiology of idiopathic subglottic stenosis by demonstrating that the genetically and socially unique Hutterites are more likely to develop this rare disease. This study is the first to demonstrate that a specific subpopulation is at a higher risk for developing idiopathic subglottic stenosis.

A case series of paediatric patients with spinal muscular atrophy type I undergoing scoliosis correction surgery.

Spinal muscular atrophy is a neuromuscular disorder with degeneration of spinal motor neurons. Type I is a severe variant that was recently shown to be amenable to treatment with the antisense oligonucleotide nusinersen. As a result of increased life expectancy with this treatment, more children with spinal muscular atrophy type I are presenting for spinal correction surgery. In this case series, we present four such patients who underwent spinal surgery at our institution over the course of one year. Pre-operative assessment showed evidence of reduced respiratory function requiring nocturnal non-invasive ventilation in all four patients. A difficult airway was encountered in two of the four patients. Postoperative complications were ubiquitous and included CSF leak, poor wound healing, metal frame exposure, frame instability and wound infection. There were no postoperative respiratory complications and all four children returned to their respiratory baseline postoperatively. All patients underwent successful lumbar puncture and intrathecal nusinersen injection following their spinal surgeries. Given the risk of complications and prolonged recovery following spinal surgery, a detailed family discussion is advisable.

Transition of care for pediatric and adult patients with venous thromboembolism: A National Quality Improvement Project from the American Thrombosis and Hemostasis Network (ATHN).

BACKGROUND: Transition of care (TOC) for management of anticoagulation from inpatient to outpatient setting for patients with acute venous thromboembolism (VTE) poses serious safety concerns. We implemented a national quality improvement educational initiative to address this issue. METHODS: Pediatric and adult patients admitted for their first VTE were prospectively enrolled at 16 centers from January 2016 to December 2018. Patient demographics, VTE diagnosis, risk factors, and treatment characteristics were collected. There were two phases: pre-intervention (PI) and quality intervention (QI). The PI phase assessed the quality and patient understanding and satisfaction of anticoagulation instructions given at hospital discharge and adherence to these instructions via a patient and/or caregiver feedback questionnaire (PFQ) and a patient knowledge questionnaire (PKQ) at 30 days. The QI phase provided patient and/or caregiver enhanced education regarding anticoagulation therapy and VTE at hospital discharge using a comprehensive discharge instruction module and a phone call follow-up at one week. Patient and/or caregiver knowledge at 7 and 30 days was assessed with the same PFQ and PKQ and compared to the PI baseline measures. RESULTS: Of the 409 study patients, 210 (51%) were adults, 218 (53%) females, and 316 (77%) White. Deep vein thrombosis (62.8%) and pulmonary embolism (47.9%) were the most common VTE in children and adults, respectively. Day 30 PFQ scores were significantly higher in the QI phase compared to the PI phase by 11% (p < 0.01). Day 30 PKQ demonstrated enhanced teaching (93.7% vs. 83.5%, p-value 0.004) and disease recognition (89.6% vs. 84.6% p = 0.03) in the QI phase than the PI phase. CONCLUSION: Comprehensive VTE discharge instructions followed by a 1-week post-discharge phone call strengthen patient and caregiver knowledge, satisfaction of education given and care provided, and disease recognition.

Bacterial community structure and response to nitrogen amendments in Lake Shenandoah (VA, USA).

Microbial processes are critical to the function of freshwater ecosystems, yet we still do not fully understand the factors that shape freshwater microbial communities. Furthermore, freshwater ecosystems are particularly susceptible to effects of environmental change, including influx of exogenous nutrients such as nitrogen and phosphorus. To evaluate the impact of nitrogen loading on the microbial community structure of shallow freshwater lakes, water samples collected from Lake Shenandoah (Virginia, USA) were incubated with two concentrations of either ammonium, nitrate, or urea as a nitrogen source. The potential impact of these nitrogen compounds on the bacterial community structure was assessed via 16S rRNA amplicon sequencing. At the phylum level, the dominant taxa in Lake Shenandoah were comprised of Actinobacteria and Proteobacteria, which were not affected by exposure to the various nitrogen treatments. Overall, there was not a significant shift in the diversity of the bacterial community of Lake Shenandoah with the addition of nitrogen sources, indicating this shallow system may be constrained by other environmental factors.

Key Performance Indicators in Paediatric Anaesthesia

Aims Currently no national guidelines on performance measurement exist for paediatric anaesthesia in Ireland1. The purpose of this study was to ascertain if we are achieving Key Performance Indicators (KPIs) in areas of post-operative nausea and vomiting (PONV) and post-operative pain when compared to international standards. Methods The study was carried out from January 2018 to February 2018 at Temple Street Children's University Hospital. In total 743 patients were included. Results 743 patients were included in the study. 86 (12%) were recorded as having a post-operative pain score of >4/10. 15 (1.2%) of patients were recorded as experiencing PONV. Orthopaedic surgery had the highest frequency of post-operative pain accounting for 33% of all cases. General surgery was associated with highest risk of PONV. Discussion The results from the study indicate we are achieving results similar to data from international centres. There is a paucity of published data from Irish centres and as national guidelines are developed for a model of care for paediatric anaesthesia we hope this data can be used when comparing other paediatric centres within Ireland.

Effect of rosuvastatin on risk markers for venous thromboembolism in cancer.

Essentials Statins lower venous thromboembolism risk in general but have not been studied in cancer patients. We completed a randomized trial of rosuvastatin vs. placebo among cancer patients on chemotherapy. Rosuvastatin did not significantly lower prothrombotic biomarkers including D-dimer. The role of statins in venous thrombosis prevention in cancer patients remains unknown. SUMMARY: Background Statin therapy is associated with lower risk of venous thromboembolism (VTE) but has not been prospectively evaluated in patients with advanced cancer. Objectives We determined if statin administration in this high-risk population reduces the risk of VTE, based on established and emerging biomarkers. Patients/Methods This double-blind, crossover, randomized controlled trial among patients with advanced cancer receiving systemic therapy allocated participants to rosuvastatin 20 mg daily or placebo for 3-4 weeks prior to crossover to the alternative therapy, with a 3-5-week washout. D-dimer, C-reactive protein (CRP), soluble (s)P-selectin, factor VIII (FVIII), thrombin generation and exploratory biomarkers focusing on endogenous thrombin potential, including tissue factor (TF), activated factor IX (FIXa) and activated factor XI (FXIa), were measured at the start and end of both treatment periods. The primary outcome was change in D-dimer with rosuvastatin compared with placebo. Results Of 38 enrolled participants, 24 (63%) completed the study. Rosuvastatin did not cause statistically significant changes in D-dimer levels or any other biomarker. CRP levels decreased by 40%; 4.3 mg L-1 (95% confidence interval, -11.0 to +2.5 mg L-1 ) compared with placebo. In post-hoc analysis, participants who received rosuvastatin initially during their first line of treatment had a 13% decrease in D-dimer. Circulating TF, FIXa and FXIa were detected in 26%, 68% and 71% of cancer patients despite not being found in healthy individuals. Conclusions Rosuvastatin did not cause favorable changes in biomarkers of VTE risk in advanced cancer patients receiving chemotherapy. The role of statin therapy as thromboprophylaxis in the cancer population remains uncertain.

A New Picture of Fire Extent, Variability, and Drought Interaction in Prescribed Fire Landscapes: Insights From Florida Government Records.

Florida, United States, government records provide a new resource for studying fire in landscapes managed with prescribed fire. In Florida, most fire area (92%) is prescribed. Current satellite fire products, which underpin most air pollution emission inventories, detect only 25% of burned area, which alters airborne emissions and environmental impacts. Moreover, these satellite products can misdiagnose spatiotemporal variability of fires. Overall fire area in Florida decreases during drought conditions as prescribed fires are avoided, but satellite data do not reflect this pattern. This pattern is consistent with prescribed fire successfully reducing overall fire risk and damages. Human management of prescribed fires and fuels can, therefore, break the conventional link between drought and wildfire and play an important role in mitigating rising fire risk in a changing climate. These results likely apply in other regions of the world with similar fire regimes.

Constraining the Spatial Extent of Marine Oil Snow Sedimentation and Flocculent Accumulation Following the Deepwater Horizon Event Using an Excess 210Pb Flux Approach.

Following the Deepwater Horizon (DWH) event in 2010, there were several lines of evidence indicating the presence of marine oil snow sedimentation and flocculent accumulation (MOSSFA). A significant amount of marine oil snow formed in the water column of the northern Gulf of Mexico (nGoM), settled rapidly, and ultimately accumulated in the sediments of the nGoM. This study utilized a commonly used radioisotope tracer (excess 210Pb, 210Pbxs) from 32 sediment cores collected from 2010 to 2013 to characterize the spatial extent of MOSSFA on the seafloor. Relative to pre-DWH conditions, an increase in 210Pbxs flux occurred in two distinct regions: (1) in the western portion of the study area on an east-northeast to west-southwest axis, stretching 230 km southwest and 140 km northeast of the DWH wellhead, and (2) in the eastern portion of the study area on a 70 km northeast to southwest axis near the DeSoto Canyon. The total sedimentary spatial extent of MOSSFA, as calculated by increased 210Pbxs flux after 2010, ranged from 12 805 to 35 425 km2. 210Pbxs flux provides a valuable tool for documenting the spatial extent of MOSSFA following DWH and will continue to aid in the determination of advective transport and ultimate depocenters of MOSSFA material.

A general framework for updating belief distributions.

We propose a framework for general Bayesian inference. We argue that a valid update of a prior belief distribution to a posterior can be made for parameters which are connected to observations through a loss function rather than the traditional likelihood function, which is recovered as a special case. Modern application areas make it increasingly challenging for Bayesians to attempt to model the true data-generating mechanism. For instance, when the object of interest is low dimensional, such as a mean or median, it is cumbersome to have to achieve this via a complete model for the whole data distribution. More importantly, there are settings where the parameter of interest does not directly index a family of density functions and thus the Bayesian approach to learning about such parameters is currently regarded as problematic. Our framework uses loss functions to connect information in the data to functionals of interest. The updating of beliefs then follows from a decision theoretic approach involving cumulative loss functions. Importantly, the procedure coincides with Bayesian updating when a true likelihood is known yet provides coherent subjective inference in much more general settings. Connections to other inference frameworks are highlighted.

Marked long-term decline in ambient CO mixing ratio in SE England, 1997-2014: evidence of policy success in improving air quality.

Atmospheric CO at Egham in SE England has shown a marked and progressive decline since 1997, following adoption of strict controls on emissions. The Egham site is uniquely positioned to allow both assessment and comparison of 'clean Atlantic background' air and CO-enriched air downwind from the London conurbation. The decline is strongest (approximately 50 ppb per year) in the 1997-2003 period but continues post 2003. A 'local CO increment' can be identified as the residual after subtraction of contemporary background Atlantic CO mixing ratios from measured values at Egham. This increment, which is primarily from regional sources (during anticyclonic or northerly winds) or from the European continent (with easterly air mass origins), has significant seasonality, but overall has declined steadily since 1997. On many days of the year CO measured at Egham is now not far above Atlantic background levels measured at Mace Head (Ireland). The results are consistent with MOPITT satellite observations and 'bottom-up' inventory results. Comparison with urban and regional background CO mixing ratios in Hong Kong demonstrates the importance of regional, as opposed to local reduction of CO emission. The Egham record implies that controls on emissions subsequent to legislation have been extremely successful in the UK.

Phase and amplitude dynamics of nonlinearly coupled oscillators.

This paper addresses the amplitude and phase dynamics of a large system of nonlinearly coupled, non-identical damped harmonic oscillators, which is based on recent research in coupled oscillation in optomechanics. Our goal is to investigate the existence and stability of collective behaviour which occurs due to a play-off between the distribution of individual oscillator frequency and the type of nonlinear coupling. We show that this system exhibits synchronisation, where all oscillators are rotating at the same rate, and that in the synchronised state the system has a regular structure related to the distribution of the frequencies of the individual oscillators. Using a geometric description, we show how changes in the non-linear coupling function can cause pitchfork and saddle-node bifurcations which create or destroy stable and unstable synchronised solutions. We apply these results to show how in-phase and anti-phase solutions are created in a system with a bi-modal distribution of frequencies.

Tumor oncogene (KRAS) status and risk of venous thrombosis in patients with metastatic colorectal cancer.

BACKGROUND: Patients with metastatic colon cancer (mCRC) are at increased risk of venous thromboembolism (VTE). Limited preclinical data suggest that the oncogene (KRAS) mutational status of the tumor represents a plausible clinical link to systemic hypercoagulability in cancer patients. OBJECTIVES: To determine if a tumor genetic characteristic, KRAS mutational status, is associated with an increased risk of VTE in patients with mCRC. PATIENTS/METHODS: A retrospective cohort study of patients with mCRC and KRAS test results was conducted at multiple practice sites across New England in the United States. The primary outcome was a VTE event, defined as deep venous thrombosis (DVT) and/or pulmonary embolism (PE), either 6 months before or at any time after the diagnosis of mCRC. KRAS status (mutated vs. wild type) and other relevant predictors of thrombosis were collected. RESULTS: Of 172 histologically confirmed patients with mCRC, 40 developed a VTE (23.3%). Sixty-five patients (37.8%) had a mutant KRAS status. The incidence of VTE and DVT among patients with mutated KRAS was 32.3 and 23.1%, respectively. The corresponding incidence among patients with wild-type KRAS was 17.8 and 9.4%. Odd ratios for the association were 2.21 (95% CI, 1.08-4.53) for VTE and 2.62 (95% CI, 1.12-6.12) for DVT, and remained significant despite adjustment for Khorana score and bevacizumab use. CONCLUSION: Tumor mutant KRAS status is associated with an increased risk of VTE in patients with mCRC. The tumor genetic profile may represent a novel and important risk factor for thrombosis in patients with cancer.

Synchronization in a mechanical resonator array coupled quadratically to a common electromagnetic field mode.

Optomechanical systems are based on the nonlinear coupling between the electromagnetic (EM) field in a resonator and one or more bulk mechanical resonators such that the frequency of the EM field resonator depends on the displacement coordinates of each of the mechanical resonators. In this paper we consider the case of multiple mechanical resonators interacting with a common field for which the frequency of the EM resonance is tuned to depend quadratically (to lowest order) on the displacement of the resonators. By using the method of amplitude equations around a critical point, it is shown that groups of near-identical bulk mechanical resonators with low driving fail to synchronize unless their natural frequencies are identical, in which case the resulting system can exhibit multistability.

Predictors of delay in the diagnosis and treatment of suspected tuberculosis in HIV co-infected patients in South Africa.

SETTING: In South Africa, the majority of tuberculosis (TB) patients are co-infected with the human immunodeficiency virus (HIV), and delays in diagnosis and treatment likely exacerbate morbidity and mortality. OBJECTIVE: To determine predictors of delays in the diagnosis and treatment of hospitalised suspected pulmonary TB patients co-infected with HIV. DESIGN: Post-analysis of data collected in a three-centre prospective cohort of in-patients clinically diagnosed with active TB in three hospitals in South Africa between 2006 and 2009 during the first 24 h of admission. Delay was assessed by asking time of first symptoms and any prior health-seeking behaviour for this episode of illness. RESULTS: Data from a total of 891 participants with a median age of 36 years and a CD4 count of 67 cells/mm(3) were analysed. Median patient, system and total delays were respectively 28, 1 and 28 days. Unemployment, treatment at Tshepong Hospital, alcohol consumption, crowding index, seeking prior treatment, cotrimoxazole treatment and WHO Stage 4 disease predicted prolonged total delay. CONCLUSION: Patient delay in seeking care for TB in this high HIV prevalence setting is substantial. Factors identified with delay could be used to develop interventions to improve care seeking and earlier diagnosis of TB.

Terahertz bandwidth photonic Hilbert transformers based on synthesized planar Bragg grating fabrication.

Terahertz bandwidth photonic Hilbert transformers are proposed and experimentally demonstrated. The integrated device is fabricated via a direct UV grating writing technique in a silica-on-silicon platform. The photonic Hilbert transformer operates at bandwidths of up to 2 THz (~16 nm) in the telecom band, a 10-fold greater bandwidth than any previously reported experimental approaches. Achieving this performance requires detailed knowledge of the system transfer function of the direct UV grating writing technique; this allows improved linearity and yields terahertz bandwidth Bragg gratings with improved spectral quality. By incorporating a flat-top reflector and Hilbert grating with a waveguide coupler, an ultrawideband all-optical single-sideband filter is demonstrated.