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To update current estimates of non–device-associated pneumonia (ND pneumonia) rates and their frequency relative to ventilator associated pneumonia (VAP), and identify risk factors for ND pneumonia.
Academic teaching hospital.
All adult hospitalizations between 2013 and 2017 were included. Pneumonia (device associated and non–device associated) were captured through comprehensive, hospital-wide active surveillance using CDC definitions and methodology.
From 2013 to 2017, there were 163,386 hospitalizations (97,485 unique patients) and 771 pneumonia cases (520 ND pneumonia and 191 VAP). The rate of ND pneumonia remained stable, with 4.15 and 4.54 ND pneumonia cases per 10,000 hospitalization days in 2013 and 2017 respectively (P = .65). In 2017, 74% of pneumonia cases were ND pneumonia. Male sex and increasing age we both associated with increased risk of ND pneumonia. Additionally, patients with chronic bronchitis or emphysema (hazard ratio [HR], 2.07; 95% confidence interval [CI], 1.40–3.06), congestive heart failure (HR, 1.48; 95% CI, 1.07–2.05), or paralysis (HR, 1.72; 95% CI, 1.09–2.73) were also at increased risk, as were those who were immunosuppressed (HR, 1.54; 95% CI, 1.18–2.00) or in the ICU (HR, 1.49; 95% CI, 1.06–2.09). We did not detect a change in ND pneumonia risk with use of chlorhexidine mouthwash, total parenteral nutrition, all medications of interest, and prior ventilation.
The incidence rate of ND pneumonia did not change from 2013 to 2017, and 3 of 4 nosocomial pneumonia cases were non–device associated. Hospital infection prevention programs should consider expanding the scope of surveillance to include non-ventilated patients. Future research should continue to look for modifiable risk factors and should assess potential prevention strategies.
To update current estimates of non–device-associated urinary tract infection (ND-UTI) rates and their frequency relative to catheter-associated UTIs (CA-UTIs) and to identify risk factors for ND-UTIs.
Academic teaching hospital.
All adult hospitalizations between 2013 and 2017 were included. UTIs (device and non-device associated) were captured through comprehensive, hospital-wide active surveillance using Centers for Disease Control and Prevention case definitions and methodology.
From 2013 to 2017 there were 163,386 hospitalizations (97,485 unique patients) and 1,273 UTIs (715 ND-UTIs and 558 CA-UTIs). The rate of ND-UTIs remained stable, decreasing slightly from 6.14 to 5.57 ND-UTIs per 10,000 hospitalization days during the study period (P = .15). However, the proportion of UTIs that were non–device related increased from 52% to 72% (P < .0001). Female sex (hazard ratio [HR], 1.94; 95% confidence interval [CI], 1.50–2.50) and increasing age were associated with increased ND-UTI risk. Additionally, the following conditions were associated with increased risk: peptic ulcer disease (HR, 2.25; 95% CI, 1.04–4.86), immunosuppression (HR, 1.48; 95% CI, 1.15–1.91), trauma admissions (HR, 1.36; 95% CI, 1.02–1.81), total parenteral nutrition (HR, 1.99; 95% CI, 1.35–2.94) and opioid use (HR, 1.62; 95% CI, 1.10–2.32). Urinary retention (HR, 1.41; 95% CI, 0.96–2.07), suprapubic catheterization (HR, 2.28; 95% CI, 0.88–5.91), and nephrostomy tubes (HR, 2.02; 95% CI, 0.83–4.93) may also increase risk, but estimates were imprecise.
Greater than 70% of UTIs are now non–device associated. Current targeted surveillance practices should be reconsidered in light of this changing landscape. We identified several modifiable risk factors for ND-UTIs, and future research should explore the impact of prevention strategies that target these factors.
Burn patients are particularly vulnerable to infection, and an estimated half of all burn deaths are due to infections. This study explored risk factors for healthcare-associated infections (HAIs) in adult burn patients.
Retrospective cohort study.
Tertiary-care burn center.
Adults (≥18 years old) admitted with burn injury for at least 2 days between 2004 and 2013.
HAIs were determined in real-time by infection preventionists using Centers for Disease Control and Prevention criteria. Multivariable Cox proportional hazards regression was used to estimate the direct effect of each risk factor on time to HAI, with inverse probability of censor weights to address potentially informative censoring. Effect measure modification by burn size was also assessed.
Overall, 4,426 patients met inclusion criteria, and 349 (7.9%) patients had at least 1 HAI within 60 days of admission. Compared to <5% total body surface area (TBSA), patients with 5%–10% TBSA were almost 3 times as likely to acquire an HAI (hazard ratio [HR], 2.92; 95% CI, 1.63–5.23); patients with 10%–20% TBSA were >6 times as likely to acquire an HAI (HR, 6.38; 95% CI, 3.64–11.17); and patients with >20% TBSA were >10 times as likely to acquire an HAI (HR, 10.33; 95% CI, 5.74–18.60). Patients with inhalational injury were 1.5 times as likely to acquire an HAI (HR, 1.61; 95% CI, 1.17–2.22). The effect of inhalational injury (P=.09) appeared to be larger among patients with ≤20% TBSA.
Larger burns and inhalational injury were associated with increased incidence of HAIs. Future research should use these risk factors to identify potential interventions.
Ventilator-associated pneumonia (VAP) is a frequent complication of severe burn injury. Comparing the current ventilator-associated event-possible VAP definition to the pre-2013 VAP definition, we identified considerably fewer VAP cases in our burn ICU. The new definition does not capture many VAP cases that would have been reported using the pre-2013 definition.
Objectives: Evaluate the association between pediatric sleep-disordered breathing (SDB) and executive functioning. Methods: We searched multiple electronic databases for peer-reviewed journal articles related to pediatric SDB and executive functioning. We included studies that assessed SDB via polysomnography, included objective or questionnaire measures of executive function, and had an age-matched control group. Fourteen articles met inclusion criteria with a total sample of 1697 children ages 5 to 17 years (M=9.81 years; SD=0.34). We calculated an overall effect size for each of the five executive domains (vigilance, inhibition, working memory, shifting, and generativity) as well as effect sizes according to SDB severity: mild, moderate, severe. We also calculated effect sizes separately for objective and subjective questionnaires of executive functioning. Results: We found a medium effect size (−0.427) for just one of five executive function domains on objective neuropsychological measures (generativity). In contrast, effect sizes on all three executive domains measured via questionnaire data were significant, with effect sizes ranging from medium (−0.64) to large (−1.06). We found no difference between executive domains by severity of SDB. Conclusions: This meta-analysis of executive function separated into five domains in pediatric SDB suggested lower performance in generativity on objective neuropsychological measures. There were no differences associated with SDB severity. Questionnaire data suggested dysfunction across the three executive domains measured (inhibition, working memory, shifting). Overall, limited evidence suggested poorer performance in executive function in children with SDB according to objective testing, and subjective ratings of executive function suggested additional worsened performance. (JINS, 2016, 22, 839–850)
A description is given of a radar facility operating in New Zealand which measures the atmospheric trajectories and hence heliocentric orbits of earth-impacting meteoroids having radiants with declinations +5° < δ < −30° down to a limiting radar meteor magnitude of +13 (corresponding to particle sizes of ~100 μm, masses ~10−6 g). The data handling capacity of the facility permits recording, orbit reduction and efficient presentation of orbital data using graphical packages to be carried out on a routine basis. The daily yield is ~1500 individual orbits with >3×105 secured to date; this is greater than the number determined in all previous meteoroid orbit surveys combined and forms a major southern hemisphere database for dynamical studies of the solar system meteoroid population.
Major depressive disorder (MDD) is moderately heritable, however genome-wide association studies (GWAS) for MDD, as well as for related continuous outcomes, have not shown consistent results. Attempts to elucidate the genetic basis of MDD may be hindered by heterogeneity in diagnosis. The Center for Epidemiological Studies Depression (CES-D) scale provides a widely used tool for measuring depressive symptoms clustered in four different domains which can be combined together into a total score but also can be analysed as separate symptom domains.
We performed a meta-analysis of GWAS of the CES-D symptom clusters. We recruited 12 cohorts with the 20- or 10-item CES-D scale (32 528 persons).
One single nucleotide polymorphism (SNP), rs713224, located near the brain-expressed melatonin receptor (MTNR1A) gene, was associated with the somatic complaints domain of depression symptoms, with borderline genome-wide significance (pdiscovery = 3.82 × 10−8). The SNP was analysed in an additional five cohorts comprising the replication sample (6813 persons). However, the association was not consistent among the replication sample (pdiscovery+replication = 1.10 × 10−6) with evidence of heterogeneity.
Despite the effort to harmonize the phenotypes across cohorts and participants, our study is still underpowered to detect consistent association for depression, even by means of symptom classification. On the contrary, the SNP-based heritability and co-heritability estimation results suggest that a very minor part of the variation could be captured by GWAS, explaining the reason of sparse findings.
Burn injuries are a common source of morbidity and mortality in the United States, with an estimated 450,000 burn injuries requiring medical treatment, 40,000 requiring hospitalization, and 3,400 deaths from burns annually in the United States. Patients with severe burns are at high risk for local and systemic infections. Furthermore, burn patients are immunosuppressed, as thermal injury results in less phagocytic activity and lymphokine production by macrophages. In recent years, multidrug-resistant (MDR) pathogens have become major contributors to morbidity and mortality in burn patients.
Since only limited data are available on the incidence of both device- and nondevice-associated healthcare-associated infections (HAIs) in burn patients, we undertook this retrospective cohort analysis of patients admitted to our burn intensive care unit (ICU) from 2008 to 2012.
Thirty pyrite samples from a wide range of localities were analysed using relative comparator and k0 neutron activation analysis (NAA) techniques at the University of Missouri Research Reactor, Columbia, Missouri, USA (MURR) and the Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, Australia (ANSTO), respectively. Statistical analyses of the trace-element data produced by the two methods showed a generally good correlation, with the majority of elemental concentrations of paired data reported by MURR and ANSTO being indistinguishable at a 0.05 significance level. Trace-element analyses of pyrite from Navajún in Spain by both techniques compare well with published data. There is evidence for contamination by Al, Na and Ti in one set of samples, this is likely to have been introduced by contact with a plastic used in sample preparation.
An jet in cross-flow (JICF) of air is studied using three-dimensional direct numerical simulation with and without chemical reaction in order to investigate the role of the complex JICF turbulent flow field in the mechanism of fast fuel-oxidant mixing and of aerodynamic flame stabilization in the near field of the jet nozzle. Focus is on delineating the flow/mixing/chemistry conditions that are necessary and/or sufficient to achieve flame anchoring that ultimately enables the formulation of more reliable and precise guidelines for design of fuel injection nozzles. A mixture averaged diffusion formulation that includes the effect of thermal diffusion is used along with a detailed chemical kinetics mechanism for hydrogen–air combustion. A new parametrization technique is used to describe the jet trajectory: solution of Laplace’s equation upon, and then within, an opportune scalar surface anchored by Dirichlet boundary conditions at the jet nozzle and plume exit from the domain provides a smoothly varying field along the jet path. The surface is selected to describe the scalar mixing and reaction associated with a transverse jet. The derived field, , is used as a condition to mark the position along the natural jet trajectory when analysing the variation of relevant flow, mixing and reaction quantities in the present direct numerical simulation (DNS) datasets. Results indicate the presence of a correlation between the flame base location in parameter space and a region of low velocity magnitude, high enstrophy, high mixing rate and high equivalence ratio (flame root region). Instantaneously, a variety of vortical structures, well known from the literature as important contributors to fuel-oxidant mixing, are observed in both inert and reactive cases with a considerable span in length scales. Moreover, instantaneous plots from reactive cases illustrate that the most upstream flame tongues propagate close to the trailing edge of the fuel jet potential core near the jet shear layer vortex shedding position. Some degree of asymmetry with respect to the domain mid-plane in the spanwise direction is observed in the averaged fields, both for the inert and reactive cases.
A thermally-activated micelle consisting of a crystallizable poly(caprolactone), PCL, core and a poly(ethylene glycol), PEG, corona was developed to contain magnetic nanoparticles and anti-cancer agent doxorubicin as well as display a targeting RGD peptide. This system has the potential to target cancer cells, deliver combination hyperthermia and chemotherapy, and offer magnetic resonance imaging contrast. The micelles self-assemble in aqueous solutions and form a crystalline core with a melting transition ranging from 40 to 50 °C, depending on the length of the PCL blocks, with dynamic light scattering showing micelle sizes typically ranging from 20 to 100 nm, depending on block lengths and added drug or nanoparticles. The micelles become unstable as they are heated above their melting point, creating a thermally-activated drug release mechanism. By adding magnetite (Fe3O4) nanoparticles into the PCL core, the micelles can be heated using an externally applied AC magnetic field to induce hyperthermia in combination with the thermally-activated drug release. The polymers and magnetic nanoparticles (MNPs) were synthesized and characterized in our laboratories. The melting transitions of the PCL micelle cores were investigated using microcalorimetry. The heating of nanoparticles and magnetomicelles was conducted using a custom-built hyperthermia coil capable of generating fields of several hundred Oersteds at frequencies ranging from 50 to 450 kHz. Heating of MNPs was maximized at high field intensities. RGD peptides were attached to the PEG corona using maleimide chemistry, and the ability of the RGD-derivatized micelles to target integrin-expressing cells was investigated using fluorescent dye PKH26 to identify the localization of micelles in cultured human kidney (293) cells in vitro. The crystallizable (and meltable) cores in these micelles were designed to overcome drug leakage common in liposome systems and release the drug on demand after a period of time for localization to integrin receptors.
To access the fermentative response of equine caecal microbial population to nitrogen availability, an in vitro study was conducted using caecal contents provided with adequate energy sources and nitrogen as limiting nutrient. Two nitrogen (N) sources were provided, protein (casein) and non-protein (urea). Caecal fluid, taken from three cannulated horses receiving a hay–concentrate diet, was mixed with a N-free buffer–mineral solution. The influence of four N levels (3.7, 6.3, 12.5 or 25 mg of N in casein or urea) was studied using the gas production technique. Total volatile fatty acids (VFA), NH3-N and gas production were measured after a 24-h incubation period. Microbial biomass was estimated using adenine and guanine bases as internal markers, and ATP production was estimated stoichiometrically. Microbial growth efficiency (YATP) and gas efficiency (Egas) were estimated. Fermentation with casein as the sole N source was generally characterized by lower total VFA, NH3-N, total gas production and higher acetate : propionate (A : P) ratio and YATP than with urea. Results herein presented indicate that, under these in vitro conditions, caecal microbial population does in fact use urea N, but less efficiently than casein in terms of microbial growth.