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11.
Elisabeth APM Romme Piet Geusens Willem F Lems Erica PA Rutten Frank WJM Smeenk Joop PW van den Bergh Peter ThW van Hal Emiel FM Wouters 《Respiratory research》2015,16(1)
Although osteoporosis and its related fractures are common in patients with COPD, patients at high risk of fracture are poorly identified, and consequently, undertreated. Since there are no fracture prevention guidelines available that focus on COPD patients, we developed a clinical approach to improve the identification and treatment of COPD patients at high risk of fracture. We organised a round-table discussion with 8 clinical experts in the field of COPD and fracture prevention in the Netherlands in December 2013. The clinical experts presented a review of the literature on COPD, osteoporosis and fracture prevention. Based on the Dutch fracture prevention guideline, they developed a 5-step clinical approach for fracture prevention in COPD. Thereby, they took into account both classical risk factors for fracture (low body mass index, older age, personal and family history of fracture, immobility, smoking, alcohol intake, use of glucocorticoids and increased fall risk) and COPD-specific risk factors for fracture (severe airflow obstruction, pulmonary exacerbations and oxygen therapy). Severe COPD (defined as postbronchodilator FEV1 < 50% predicted) was added as COPD-specific risk factor to the list of classical risk factors for fracture. The 5-step clinical approach starts with case finding using clinical risk factors, followed by risk evaluation (dual energy X-ray absorptiometry and imaging of the spine), differential diagnosis, treatment and follow-up. This systematic clinical approach, which is evidence-based and easy-to-use in daily practice by pulmonologists, should contribute to optimise fracture prevention in COPD patients at high risk of fracture. 相似文献
12.
Fei Liu Yingju Liu Rui‐Gang Xu Guifu Dai Liu‐Xi Zhao Yafeng Wang Hong‐Min Liu Feng‐Wu Liu Christophe Pannecouque Piet Herdewijn 《化学与生物多样性》2015,12(5):813-822
The synthesis of [(2′,5′‐dihydrofuran‐2‐yl)oxy]methyl‐phosphonate nucleosides with a 2‐substituted adenine base moiety starting from 2‐deoxy‐3,5‐bis‐O‐(4‐methylbenzoyl)‐α‐L ‐ribofuranosyl chloride and 2,6‐dichloropurine is described. The key step is the regiospecific and stereoselective introduction of a phosphonate synthon at C(2) of the furan ring. None of the synthesized compounds showed significant in vitro activity against HIV, BVDV, and HBV. 相似文献
13.
Claire H. den Hoedt Muriel P. C. Grooteman Michiel L. Bots Peter J. Blankestijn Ingeborg van der Tweel Neelke C. van der Weerd E. Lars Penne Albert H. A. Mazairac Renée Levesque Piet M. ter Wee Menso J. Nubé Marinus A. van den Dorpel CONTRAST investigators 《PloS one》2015,10(8)
Background
Hemodialysis (HD) patients have a high risk of infections. The uremic milieu has a negative impact on several immune responses. Online hemodiafiltration (HDF) may reduce the risk of infections by ameliorating the uremic milieu through enhanced clearance of middle molecules. Since there are few data on infectious outcomes in HDF, we compared the effects of HDF with low-flux HD on the incidence and type of infections.Patients and Methods
We used data of the 714 HD patients (age 64 ±14, 62% men, 25% Diabetes Mellitus, 7% catheters) participating in the CONvective TRAnsport STudy (CONTRAST), a randomized controlled trial evaluating the effect of HDF as compared to low-flux HD. The events were adjudicated by an independent event committee. The risk of infectious events was compared with Cox regression for repeated events and Cox proportional hazard models. The distributions of types of infection were compared between the groups.Results
Thirty one percent of the patients suffered from one or more infections leading to hospitalization during the study (median follow-up 1.96 years). The risk for infections during the entire follow-up did not differ significantly between treatment arms (HDF 198 and HD 169 infections in 800 and 798 person-years respectively, hazard ratio HDF vs. HD 1.09 (0.88–1.34), P = 0.42. No difference was found in the occurrence of the first infectious event (either fatal, non-fatal or type specific). Of all infections, respiratory infections (25% in HDF, 28% in HD) were most common, followed by skin/musculoskeletal infections (21% in HDF, 13% in HD).Conclusions
HDF as compared to HD did not result in a reduced risk of infections, larger studies are needed to confirm our findings.Trial Registration
ClinicalTrials.gov NCT00205556 相似文献14.
Camiel L. M. de Roij van Zuijdewijn Muriel P. C. Grooteman Michiel L. Bots Peter J. Blankestijn Sonja Steppan Janine Büchel Rolf H. H. Groenwold Vincent Brandenburg Marinus A. van den Dorpel Piet M. ter Wee Menso J. Nubé Marc G. Vervloet 《PloS one》2015,10(11)
Despite suggestions that higher serum magnesium (Mg) levels are associated with improved outcome, the association with mortality in European hemodialysis (HD) patients has only scarcely been investigated. Furthermore, data on the association between serum Mg and sudden death in this patient group is limited. Therefore, we evaluated Mg in a post-hoc analysis using pooled data from the CONvective TRAnsport STudy (CONTRAST, NCT00205556), a randomized controlled trial (RCT) evaluating the survival risk in dialysis patients on hemodiafiltration (HDF) compared to HD with a mean follow-up of 3.1 years. Serum Mg was measured at baseline and 6, 12, 24 and 36 months thereafter. Cox proportional hazards models, adjusted for confounders using inverse probability weighting, were used to estimate hazard ratios (HRs) of baseline serum Mg on all-cause mortality, cardiovascular mortality, non-cardiovascular mortality and sudden death. A generalized linear mixed model was used to investigate Mg levels over time. Out of 714 randomized patients, a representative subset of 365 (51%) were analyzed in the present study. For every increase in baseline serum Mg of 0.1 mmol/L, the HR for all-cause mortality was 0.85 (95% CI 0.77–94), the HR for cardiovascular mortality 0.73 (95% CI 0.62–0.85) and for sudden death 0.76 (95% CI 0.62–0.93). These findings did not alter after extensive correction for potential confounders, including treatment modality. Importantly, no interaction was found between serum phosphate and serum Mg. Baseline serum Mg was not related to non-cardiovascular mortality. Mg decreased slightly but statistically significant over time (Δ -0.011 mmol/L/year, 95% CI -0.017 to -0.009, p = 0.03). In short, serum Mg has a strong, independent association with all-cause mortality, cardiovascular mortality and sudden death in European HD patients. Serum Mg levels decrease slightly over time. 相似文献
15.
16.
Marijn Bauters Sofie Meeus Matti Barthel Piet Stoffelen Hannes P. T. De Deurwaerder Flicien Meunier Travis W. Drake Quentin Ponette Jerme Ebuy Pieter Vermeir Hans Beeckman Francis wyffels Samuel Bod Hans Verbeeck Filip Vandelook Pascal Boeckx 《Global Change Biology》2020,26(8):4449-4461
Forests exhibit leaf‐ and ecosystem‐level responses to environmental changes. Specifically, rising carbon dioxide (CO2) levels over the past century are expected to have increased the intrinsic water‐use efficiency (iWUE) of tropical trees while the ecosystem is gradually pushed into progressive nutrient limitation. Due to the long‐term character of these changes, however, observational datasets to validate both paradigms are limited in space and time. In this study, we used a unique herbarium record to go back nearly a century and show that despite the rise in CO2 concentrations, iWUE has decreased in central African tropical trees in the Congo Basin. Although we find evidence that points to leaf‐level adaptation to increasing CO2—that is, increasing photosynthesis‐related nutrients and decreasing maximum stomatal conductance, a decrease in leaf δ13C clearly indicates a decreasing iWUE over time. Additionally, the stoichiometric carbon to nitrogen and nitrogen to phosphorus ratios in the leaves show no sign of progressive nutrient limitation as they have remained constant since 1938, which suggests that nutrients have not increasingly limited productivity in this biome. Altogether, the data suggest that other environmental factors, such as increasing temperature, might have negatively affected net photosynthesis and consequently downregulated the iWUE. Results from this study reveal that the second largest tropical forest on Earth has responded differently to recent environmental changes than expected, highlighting the need for further on‐ground monitoring in the Congo Basin. 相似文献
17.
In the past decade, we have witnessed a revolution in osteoporosis diagnosis and therapeutics. This includes enhanced understanding
of basic bone biology, recognizing the severe consequences of fractures in terms of morbidity and short-term re-fracture and
mortality risk and case finding based on clinical risks, bone mineral density, new imaging approaches, and contributors to
secondary osteoporosis. Medical interventions that reduce fracture risk include sufficient calcium and vitamin D together
with a wide spectrum of drug therapies (with antiresorptive, anabolic, or mixed effects). Emerging therapeutic options that
target molecules of bone metabolism indicate that the next decade should offer even greater promise for further improving
our diagnostic and treatment approaches. 相似文献
18.
Inflammatory rheumatic diseases are generally multifaceted disorders and, therefore, measurement of multiple outcomes is relevant
to most of these diseases. Developments in outcome measures in the rheumatic diseases are promoted by the development of successful
treatments. Outcome measurement will increasingly deal with measurement of low levels of disease activity and avoidance of
disease consequences. It is an advantage for patient management and knowledge transfer if the same outcomes are used in practice
and in trials. Continuous measures of change are generally the most powerful and, therefore, are preferred as primary outcomes
in trials. For daily clinical practice, outcome measures should reflect the patients' state and have to be easily derivable.
The objective of this review is to describe recent developments in outcome measures for inflammatory rheumatic diseases for
trials and clinical practice, with an emphasis on rheumatoid arthritis. 相似文献
19.
Changes in metacarpal cortical bone mineral density (BMD) using digital x-ray radiogrammetry were studied in patients with
early rheumatoid arthritis. After 1, 2, and 5 years, large BMD losses were found: -1.7%, -2.8%, and -5.6%, respectively. Elevated
erythrocyte sedimentation rate and anti-cyclic citrullinated peptide levels were independent predictors of bone loss, indicating
that the largest amount of bone loss was found in patients with severe inflammation and high production of auto-antibodies,
who are known to be at the highest risk of developing radiological bone damage. Studies are needed about the spatial and time
relationship between erosions and juxta-articular and metacarpal bone loss. 相似文献
20.
Jan Bartacek Isabella Manconi Gerardo Sansone Roberta Murgia Piet N.L. Lens 《Nitric oxide》2010,22(2):101-105
Hydrogen sulfide (H2S) inhibits the last step of the denitrification process, i.e. the reduction of nitrous oxide (N2O) to dinitrogen gas (N2), both in natural environments (marine sediments) and industrial processes (activated sludge, methanogenic sludge, BioDeNOx process). In a previously published study, we showed that the inhibitory effect of sulfide to N2O reduction in mixed microbial communities is reversible and can be counteracted by dosing trace amounts of copper. It remained, however, unclear if this was due to copper sulfide precipitation or a retrofitting of the copper containing N2O-reductase (N2OR). The present study aimed to elucidate the mechanism of the restoration of sulfide-inhibited N2O reducing activity by metal addition to a pure Pseudomonas aeruginosa culture. This was done by using other metals (zinc, cobalt and iron) in comparison with copper. Zinc and cobalt clearly alleviated the sulfide inhibition of N2OR to the same extent as copper and the activity restoration was extremely fast (within 15 min, Fig. 3) for zinc, cobalt and copper. This suggests that the alleviation of the inhibitory effect of sulfide is due to metal sulfide precipitation and thus not exclusively limited to Cu. This work also underlines the importance of metal speciation: supply of iron did not restore the N2OR activity because it was precipitated by the phosphates present in the medium and thus could not precipitate the sulfide. 相似文献