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排序方式: 共有963条查询结果,搜索用时 15 毫秒
51.
Benedetta Artegiani Lisa van Voorthuijsen Rik G.H. Lindeboom Daniëlle Seinstra Inha Heo Pablo Tapia Carmen López-Iglesias Daniel Postrach Talya Dayton Rurika Oka Huili Hu Ruben van Boxtel Johan H. van Es Johan Offerhaus Peter J. Peters Jacco van Rheenen Michiel Vermeulen Hans Clevers 《Cell Stem Cell》2019,24(6):927-943.e6
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Gijs Fortrie Susanne Stads Albert-Jan H. Aarnoudse Robert Zietse Michiel G. Betjes 《PloS one》2015,10(3)
Background and Objectives
Acute kidney injury (AKI) necessitating renal replacement therapy (RRT) is associated with high mortality and increased risk for end stage renal disease. However, it is unknown if this applies to patients with a preliminary unremarkable medical history. The purpose of this study was to describe overall and renal survival in critically ill patients with AKI necessitating RRT stratified by the presence of comorbidity.Design, Setting, Participants, and Measurements
A retrospective cohort study was performed, between 1994 and 2010, including all adult critically ill patients with AKI necessitating RRT, stratified by the presence of comorbidity. Logistic regression, survival curve and cox proportional hazards analyses were used to evaluate overall and renal survival. Standardized mortality rate (SMR) analysis was performed to compare long-term survival to the predicted survival in the Dutch population.Results
Of the 1067 patients included only 96(9.0%) had no comorbidity. Hospital mortality was 56.6% versus 43.8% in patients with and without comorbidity, respectively. In those who survived hospitalization 10-year survival was 45.0% and 86.0%, respectively. Adjusted for age, sex and year of treatment, absence of comorbidity was not associated with hospital mortality (OR=0.74, 95%-CI=0.47-1.15), while absence of comorbidity was associated with better long-term survival (adjusted HR=0.28, 95%-CI = 0.14-0.58). Compared to the Dutch population, patients without comorbidity had a similar mortality risk (SMR=1.6, 95%-CI=0.7-3.2), while this was increased in patients with comorbidity (SMR=4.8, 95%-CI=4.1-5.5). Regarding chronic dialysis dependency, 10-year renal survival rates were 76.0% and 92.9% in patients with and without comorbidity, respectively. Absence of comorbidity was associated with better renal survival (adjusted HR=0.24, 95%-CI=0.07-0.76).Conclusions
While hospital mortality remains excessively high, the absence of comorbidity in critically ill patients with RRT-requiring AKI is associated with a relative good long-term prognosis in those who survive hospitalization. 相似文献56.
Bart B. L. Groen Astrid M. Horstman Henrike M. Hamer Michiel de Haan Janneau van Kranenburg J?rgen Bierau Martijn Poeze Will K. W. H. Wodzig Blake B. Rasmussen Luc J. C. van Loon 《PloS one》2015,10(11)
Background
Protein turnover in skeletal muscle tissue is highly responsive to nutrient intake in healthy adults.Objective
To provide a comprehensive overview of post-prandial protein handling, ranging from dietary protein digestion and amino acid absorption, the uptake of dietary protein derived amino acids over the leg, the post-prandial stimulation of muscle protein synthesis rates, to the incorporation of dietary protein derived amino acids in de novo muscle protein.Design
12 healthy young males ingested 20 g intrinsically [1-13C]-phenylalanine labeled protein. In addition, primed continuous L-[ring-2H5]-phenylalanine, L-[ring-2H2]-tyrosine, and L-[1-13C]-leucine infusions were applied, with frequent collection of arterial and venous blood samples, and muscle biopsies throughout a 5 h post-prandial period. Dietary protein digestion, amino acid absorption, splanchnic amino acid extraction, amino acid uptake over the leg, and subsequent muscle protein synthesis were measured within a single in vivo human experiment.Results
55.3±2.7% of the protein-derived phenylalanine was released in the circulation during the 5 h post-prandial period. The post-prandial rise in plasma essential amino acid availability improved leg muscle protein balance (from -291±72 to 103±66 μM·min-1·100 mL leg volume-1; P<0.001). Muscle protein synthesis rates increased significantly following protein ingestion (0.029±0.002 vs 0.044±0.004%·h-1 based upon the muscle protein bound L-[ring-2H5]-phenylalanine enrichments (P<0.01)), with substantial incorporation of dietary protein derived L-[1-13C]-phenylalanine into de novo muscle protein (from 0 to 0.0201±0.0025 MPE).Conclusion
Ingestion of a single meal-like amount of protein allows ~55% of the protein derived amino acids to become available in the circulation, thereby improving whole-body and leg protein balance. About 20% of the dietary protein derived amino acids released in the circulation are taken up in skeletal muscle tissue following protein ingestion, thereby stimulating muscle protein synthesis rates and providing precursors for de novo muscle protein synthesis.Trial Registration
trialregister.nl 3638 相似文献57.
Justin V. Joseph Ingrid A. M. van Roosmalen Ellen Busschers Tushar Tomar Siobhan Conroy Ellie Eggens-Meijer Natalia Pe?aranda Fajardo Milind M. Pore Veerakumar Balasubramanyian Michiel Wagemakers Sjef Copray Wilfred F. A. den Dunnen Frank A. E. Kruyt 《PloS one》2015,10(12)
Glioblastoma (GBM) is a highly infiltrative brain tumor in which cells with properties of stem cells, called glioblastoma stem cells (GSCs), have been identified. In general, the dominant view is that GSCs are responsible for the initiation, progression, invasion and recurrence of this tumor. In this study, we addressed the question whether the differentiation status of GBM cells is associated with their invasive capacity. For this, several primary GBM cell lines were used, cultured either as neurospheres known to enrich for GSCs or in medium supplemented with 10% FCS that promotes differentiation. The differentiation state of the cells was confirmed by determining the expression of stem cell and differentiation markers. The migration/invasion potential of these cells was tested using in vitro assays and intracranial mouse models. Interestingly, we found that serum-induced differentiation enhanced the invasive potential of GBM cells, which was associated with enhanced MMP9 expression. Chemical inhibition of MMP9 significantly reduced the invasive potential of differentiated cells in vitro. Furthermore, the serum-differentiated cells could revert back to an undifferentiated/stem cell state that were able to form neurospheres, although with a reduced efficiency as compared to non-differentiated counterparts. We propose a model in which activation of the differentiation program in GBM cells enhances their infiltrative potential and that depending on microenvironmental cues a significant portion of these cells are able to revert back to an undifferentiated state with enhanced tumorigenic potential. Thus, effective therapy should target both GSCs and differentiated offspring and targeting of differentiation-associated pathways may offer therapeutic opportunities to reduce invasive growth of GBM. 相似文献
58.
Michiel van Elk 《PloS one》2015,10(6)
Previous studies have shown that one’s prior beliefs have a strong effect on perceptual decision-making and attentional processing. The present study extends these findings by investigating how individual differences in paranormal and conspiracy beliefs are related to perceptual and attentional biases. Two field studies were conducted in which visitors of a paranormal conducted a perceptual decision making task (i.e. the face / house categorization task; Experiment 1) or a visual attention task (i.e. the global / local processing task; Experiment 2). In the first experiment it was found that skeptics compared to believers more often incorrectly categorized ambiguous face stimuli as representing a house, indicating that disbelief rather than belief in the paranormal is driving the bias observed for the categorization of ambiguous stimuli. In the second experiment, it was found that skeptics showed a classical ‘global-to-local’ interference effect, whereas believers in conspiracy theories were characterized by a stronger ‘local-to-global interference effect’. The present study shows that individual differences in paranormal and conspiracy beliefs are associated with perceptual and attentional biases, thereby extending the growing body of work in this field indicating effects of cultural learning on basic perceptual processes. 相似文献
59.
Michiel Etienne Janssens Dirk Geysen Katleen Broos Ine De Goeyse Johan Robbens Filip Van Petegem Jean-Pierre Timmermans Yves Guisez 《Amino acids》2010,38(5):1617-1626
The hepatitis B core (HBc) protein has been used successfully in numerous experiments as a carrier for heterologous peptides.
Folding and capsid formation of the chimeric proteins is not always achieved easily. In silico analyses were performed to
provide further comprehension of the feasibility for predicting successful capsid formation. In contrast to previous work,
we show that common in silico predictions do not ensure assembly into particles. We included new considerations regarding
capsid formation of HBc fusion proteins. Not only the primary sequence and the length of the inserts seem important, also
the rigidity, the distance between the N and the C-terminus and the presence of cysteines, which could form disulphide bonds,
could influence proper capsid formation. Furthermore, new conformational insights were formulated when linkers were added
to create extra flexibility of the chimeric particles. Different hypotheses were suggested to clarify the obtained results.
To this extent, the addition of glycine-rich linkers could lower high rigidity of the insert, removal of the strain of the
core protein or ease interaction between the HBc and the insert. Finally, we observed specific changes in capsid formation
properties when longer linkers were used. These findings have not been reported before in this and other virus-like particle
carriers. In this study, we also propose a new high-yield purification protocol for fusion proteins to be used in vaccination
experiments with the carrier protein or in comparative studies of particulate or non-particulate HBc fusion proteins. 相似文献
60.
Nigel E. Stork 《Biodiversity and Conservation》2010,19(2):357-371
There is a widespread belief that we are experiencing a mass extinction event similar in severity to previous mass extinction
events in the last 600 million years where up to 95% of species disappeared. This paper reviews evidence for current extinctions
and different methods of assessing extinction rates including species–area relationships and loss of tropical forests, changing
threat status of species, co-extinction rates and modelling the impact of climate change. For 30 years some have suggested
that extinctions through tropical forest loss are occurring at a rate of up to 100 species a day and yet less than 1,200 extinctions
have been recorded in the last 400 years. Reasons for low number of identified global extinctions are suggested here and include
success in protecting many endangered species, poor monitoring of most of the rest of species and their level of threat, extinction
debt where forests have been lost but species still survive, that regrowth forests may be important in retaining ‘old growth’
species, fewer co-extinctions of species than expected, and large differences in the vulnerability of different taxa to extinction
threats. More recently, others have suggested similar rates of extinction to earlier estimates but with the key cause of extinction
being climate change, and in particular rising temperatures, rather than deforestation alone. Here I suggest that climate
change, rather than deforestation is likely to bring about such high levels of extinction since the impacts of climate change
are local to global and that climate change is acting synergistically with a range of other threats to biodiversity including
deforestation. 相似文献