174 research outputs found
Identification of a Novel Genomic Island Associated with vanD-Type Vancomycin Resistance in Six Dutch Vancomycin-Resistant Enterococcus faecium Isolates
Genomic comparison of the first six Dutch vanD-type vancomycin-resistant Enterococcus faecium (VRE) isolates with four vanD gene clusters from other enterococcal species and anaerobic gut commensals revealed that the vanD gene cluster was located on a genomic island of variable size. Phylogenetic inferences revealed that the Dutch VRE isolates were genetically not closely related and that genetic variation of the vanD-containing genomic island was not species specific, suggesting that this island is transferred horizontally between enterococci and anaerobic gut commensals.Peer reviewe
Global warming shifts the composition of the abundant bacterial phyllosphere microbiota as indicated by a cultivation dependent and independent study of the grassland phyllosphere of a long-term warming field-experiment
Plant science
MAXI J1659-152: The shortest orbital period black-hole transient in outburst
MAXI J1659-152 is a bright X-ray transient black-hole candidate binary system
discovered in September 2010. We report here on MAXI, RXTE, Swift, and
XMM-Newton observations during its 2010/2011 outburst. We find that during the
first one and a half week of the outburst the X-ray light curves display drops
in intensity at regular intervals, which we interpret as absorption dips. About
three weeks into the outbursts, again drops in intensity are seen. These dips
have, however, a spectral behaviour opposite to that of the absorption dips,
and are related to fast spectral state changes (hence referred to as transition
dips). The absorption dips recur with a period of 2.414+/-0.005 hrs, which we
interpret as the orbital period of the system. This implies that MAXI J1659-152
is the shortest period black-hole candidate binary known to date. The
inclination of the accretion disk with respect to the line of sight is
estimated to be 65-80 degrees. We propose the companion to the black-hole
candidate to be close to an M5 dwarf star, with a mass and radius of about
0.15-0.25 M_sun and 0.2-0.25 R_sun, respectively. We derive that the companion
had an initial mass of about 1.5 M_sun, which evolved to its current mass in
about 5-6 billion years. The system is rather compact (orbital separation of
larger than ~1.33 R_sun), and is located at a distance of 8.6+/-3.7 kpc, with a
height above the Galactic plane of 2.4+/-1.0 kpc. The characteristics of short
orbital period and high Galactic scale height are shared with two other
transient black-hole candidate X-ray binaries, i.e., XTE J1118+480 and Swift
J1735.5-0127. We suggest that all three are kicked out of the Galactic plane
into the halo, rather than being formed in a globular cluster.Comment: 20 pages, 14 figures, accepted for publication in A&
PET and MRI for the evaluation of regional myocardial perfusion and wall thickening after myocardial infarction
Deterioration of left ventricular (LV) function after myocardial infarction (MI) is a major cause of heart failure. Myocardial perfusion performance may play an important role in deterioration or improvement in LV function after MI. The aim of this study was to evaluate the myocardial perfusion reserve (MPR) and stress perfusion in deteriorating and non-deteriorating LV segments in patients after MI by PET and MRI, respectively.
Regional wall thickening of 352 segments in 22 patients was assessed at 4 and 24 months after MI by cardiac MRI. PET was performed to evaluate MPR and adenosine stress N-13-ammonia perfusion 24 months after MI. Segments were divided into four groups according to deterioration or improvement in wall thickening.
Normal functional segments at 4 months after MI that remained stable had a significantly higher mean MPR and mean stress perfusion PET value than deteriorated segments (p < 0.001). Furthermore, dysfunctional segments that improved had a significantly higher mean stress perfusion PET value than dysfunctional segments that remained dysfunctional (p < 0.001).
This study demonstrated the additional value of myocardial perfusion assessment in relation to the functional integrity of the injured myocardium. Segmental functional LV improvement after MI was associated with better regional myocardial perfusion characteristics. Furthermore, the amount of wall thickening reduction was associated with regional myocardial perfusion abnormalities in patients after MI
Characteristics and outcomes of older patients hospitalised for COVID-19 in the first and second wave of the pandemic in The Netherlands:the COVID-OLD study
BACKGROUND: as the coronavirus disease of 2019 (COVID-19) pandemic progressed diagnostics and treatment changed. OBJECTIVE: to investigate differences in characteristics, disease presentation and outcomes of older hospitalised COVID-19 patients between the first and second pandemic wave in The Netherlands. METHODS: this was a multicentre retrospective cohort study in 16 hospitals in The Netherlands including patients aged ≥ 70 years, hospitalised for COVID-19 in Spring 2020 (first wave) and Autumn 2020 (second wave). Data included Charlson comorbidity index (CCI), disease severity and Clinical Frailty Scale (CFS). Main outcome was in-hospital mortality. RESULTS: a total of 1,376 patients in the first wave (median age 78 years, 60% male) and 946 patients in the second wave (median age 79 years, 61% male) were included. There was no relevant difference in presence of comorbidity (median CCI 2) or frailty (median CFS 4). Patients in the second wave were admitted earlier in the disease course (median 6 versus 7 symptomatic days; P < 0.001). In-hospital mortality was lower in the second wave (38.1% first wave versus 27.0% second wave; P < 0.001). Mortality risk was 40% lower in the second wave compared with the first wave (95% confidence interval: 28–51%) after adjustment for differences in patient characteristics, comorbidity, symptomatic days until admission, disease severity and frailty. CONCLUSIONS: compared with older patients hospitalised in the first COVID-19 wave, patients in the second wave had lower in-hospital mortality, independent of risk factors for mortality. The better prognosis likely reflects earlier diagnosis, the effect of improvement in treatment and is relevant for future guidelines and treatment decisions
Greenhouse gases from agriculture
The rapidly changing global climate due to increased emission of anthropogenic greenhouse gases (GHGs) is leading to an increased occurrence of extreme weather events such as droughts, floods, and heatwaves. The three major GHGs are carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). The major natural sources of CO2 include ocean-atmosphere exchange, respiration of animals, soils (microbial respiration) and plants, and volcanic eruption; while the anthropogenic sources include burning of fossil fuel (coal, natural gas, and oil), deforestation, and the cultivation of land that increases the decomposition of soil organic matter and crop and animal residues. Natural sources of CH4 emission include wetlands, termite activities, and oceans. Paddy fields used for rice production, livestock production systems (enteric emission from ruminants), landfills, and the production and use of fossil fuels are the main anthropogenic sources of CH4. Nitrous oxide, in addition to being a major GHG, is also an ozone-depleting gas. N2O is emitted by natural processes from oceans and terrestrial ecosystems. Anthropogenic N2O emissions occur mostly through agricultural and other land-use activities and are associated with the intensification of agricultural and other human activities such as increased use of synthetic fertiliser (119.4 million tonnes of N worldwide in 2019), inefficient use of irrigation water, deposition of animal excreta (urine and dung) from grazing animals, excessive and inefficient application of farm effluents and animal manure to croplands and pastures, and management practices that enhance soil organic N mineralisation and C decomposition. Agriculture could act as a source and a sink of GHGs. Besides direct sources, GHGs also come from various indirect sources, including upstream and downstream emissions in agricultural systems and ammonia (NH3) deposition from fertiliser and animal manure
Micrometeorological methods for greenhouse gas measurement
Micrometeorological techniques are useful if greenhouse gas (GHG) emissions from larger areas (i.e. entire fields) should be integrated. The theory and the various techniques such as flux-gradient, aerodynamic, and Bowen ratio as well as Eddy correlationmethods are described and discussed. Alternativemethods also used areEddy correlation, mass balance techniques, and tracer-based methods.The analytical techniques with current state-of-the-art approaches as well as the calculation procedures are presented
Delirium in older COVID-19 patients:Evaluating risk factors and outcomes
Objectives: A high incidence of delirium has been reported in older patients with Coronavirus disease 2019 (COVID-19). We aimed to identify determinants of delirium, including the Clinical Frailty Scale, in hospitalized older patients with COVID-19. Furthermore, we aimed to study the association of delirium independent of frailty with in-hospital outcomes in older COVID-19 patients. Methods: This study was performed within the framework of the multi-center COVID-OLD cohort study and included patients aged ≥60 years who were admitted to the general ward because of COVID-19 in the Netherlands between February and May 2020. Data were collected on demographics, co-morbidity, disease severity, and geriatric parameters. Prevalence of delirium during hospital admission was recorded based on delirium screening using the Delirium Observation Screening Scale (DOSS) which was scored three times daily. A DOSS score ≥3 was followed by a delirium assessment by the ward physician In-hospital outcomes included length of stay, discharge destination, and mortality. Results: A total of 412 patients were included (median age 76, 58% male). Delirium was present in 82 patients. In multivariable analysis, previous episode of delirium (Odds ratio [OR] 8.9 [95% CI 2.3–33.6] p = 0.001), and pre-existent memory problems (OR 7.6 [95% CI 3.1–22.5] p < 0.001) were associated with increased delirium risk. Clinical Frailty Scale was associated with increased delirium risk (OR 1.63 [95%CI 1.40–1.90] p < 0.001) in univariable analysis, but not in multivariable analysis. Patients who developed delirium had a shorter symptom duration and lower levels of C-reactive protein upon presentation, whereas vital parameters did not differ. Patients who developed a delirium had a longer hospital stay and were more often discharged to a nursing home. Delirium was associated with mortality (OR 2.84 [95% CI1.71–4.72] p < 0.001), but not in multivariable analyses. Conclusions: A previous delirium and pre-existent memory problems were associated with delirium risk in COVID-19. Delirium was not an independent predictor of mortality after adjustment for frailty
Smoking cessation and bronchial epithelial remodelling in COPD: a cross-sectional study
<p>Abstract</p> <p>Background</p> <p>Chronic Obstructive Pulmonary Disease (COPD) is associated with bronchial epithelial changes, including squamous cell metaplasia and goblet cell hyperplasia. These features are partially attributed to activation of the epidermal growth factor receptor (EGFR). Whereas smoking cessation reduces respiratory symptoms and lung function decline in COPD, inflammation persists. We determined epithelial proliferation and composition in bronchial biopsies from current and ex-smokers with COPD, and its relation to duration of smoking cessation.</p> <p>Methods</p> <p>114 COPD patients were studied cross-sectionally: 99 males/15 females, age 62 ± 8 years, median 42 pack-years, no corticosteroids, current (n = 72) or ex-smokers (n = 42, median cessation duration 3.5 years), postbronchodilator FEV<sub>1 </sub>63 ± 9% predicted. Squamous cell metaplasia (%), goblet cell (PAS/Alcian Blue<sup>+</sup>) area (%), proliferating (Ki-67<sup>+</sup>) cell numbers (/mm basement membrane), and EGFR expression (%) were measured in intact epithelium of bronchial biopsies.</p> <p>Results</p> <p>Ex-smokers with COPD had significantly less epithelial squamous cell metaplasia, proliferating cell numbers, and a trend towards reduced goblet cell area than current smokers with COPD (p = 0.025, p = 0.001, p = 0.081, respectively), but no significant difference in EGFR expression. Epithelial features were not different between short-term quitters (<3.5 years) and current smokers. Long-term quitters (≥3.5 years) had less goblet cell area than both current smokers and short-term quitters (medians: 7.9% vs. 14.4%, p = 0.005; 7.9% vs. 13.5%, p = 0.008; respectively), and less proliferating cell numbers than current smokers (2.8% vs. 18.6%, p < 0.001).</p> <p>Conclusion</p> <p>Ex-smokers with COPD had less bronchial epithelial remodelling than current smokers, which was only observed after long-term smoking cessation (>3.5 years).</p> <p>Trial registration</p> <p>NCT00158847</p
Multidrug resistance-associated protein-1 (MRP1) genetic variants, MRP1 protein levels and severity of COPD
<p>Abstract</p> <p>Background</p> <p>Multidrug resistance-associated protein-1 (MRP1) protects against oxidative stress and toxic compounds generated by cigarette smoking, which is the main risk factor for chronic obstructive pulmonary disease (COPD). We have previously shown that single nucleotide polymorphisms (SNPs) in <it>MRP1 </it>significantly associate with level of FEV<sub>1 </sub>in two independent population based cohorts. The aim of our study was to assess the associations of <it>MRP1 </it>SNPs with FEV<sub>1 </sub>level, MRP1 protein levels and inflammatory markers in bronchial biopsies and sputum of COPD patients.</p> <p>Methods</p> <p>Five SNPs (rs212093, rs4148382, rs504348, rs4781699, rs35621) in <it>MRP1 </it>were genotyped in 110 COPD patients. The effects of <it>MRP1 </it>SNPs were analyzed using linear regression models.</p> <p>Results</p> <p>One SNP, rs212093 was significantly associated with a higher FEV<sub>1 </sub>level and less airway wall inflammation. Another SNP, rs4148382 was significantly associated with a lower FEV<sub>1 </sub>level, higher number of inflammatory cells in induced sputum and with a higher MRP1 protein level in bronchial biopsies.</p> <p>Conclusions</p> <p>This is the first study linking <it>MRP1 </it>SNPs with lung function and inflammatory markers in COPD patients, suggesting a role of <it>MRP1 </it>SNPs in the severity of COPD in addition to their association with MRP1 protein level in bronchial biopsies.</p
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