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101.
Barth Oeseburg Jos Schols Marcel Olde Rikkert Henriëtte van der Horst Dini Smilde-van den Doel Sophia de Rooij Bianca Buurman-van Es Marieke Schuurmans Jacobijn Gussekloo 《Tijdschrift voor gerontologie en geriatrie》2016,47(6):272-281
The Netherlands Organisation of Health Research and Development started in 2008 the Dutch National Care for the Elderly Programme (in Dutch abbreviated as NPO) with the aim to improve the quality of life for the frail older people through better quality of care (health, social, community) which is tailored to the needs and wants of older people. The delivery of good care is related with competent professional behaviour which is inextricably linked to the education of professionals. This article presents an overview of 32 educational programmes developed within the NPO. Within the NPO different educational programmes were developed on relevant themes to improve elderly care. However, the programmes focused mainly on professionals in health care, especially those working in primary care. For nurses and nursing assistants and more or less for physicians also different educational programmes were developed. Educational programmes for paramedics or professionals working in social care, housing or in the municipalities were scarce. This is also the case for specific themes in elderly care like loneliness or (domestic) violence. Moreover, none of the experiments focused on older people or informal care givers. Although 22 of the 32 projects developed educational programmes for different groups, multi – or interdisciplinary education is rare in these programmes. Based on the overview we advise the development of more educational programmes on: target groups which were less or not addressed in the NPO, like professionals in social care and paramedics; multi- or interdisciplinary collaboration; and themes, like loneliness in older people and elder abuse. 相似文献
102.
Pouya Jelvehgaran Daniel M. de Bruin Artem Khmelinskii Gerben Borst Jeffrey D. Steinberg Ji‐Ying Song Judith de Vos Ton G. van Leeuwen Tanja Alderliesten Johannes F. de Boer Marcel van Herk 《Journal of biophotonics》2019,12(9)
Radiation therapy for patients with non‐small‐cell lung cancer is hampered by acute radiation‐induced toxicity in the esophagus. This study aims to validate that optical coherence tomography (OCT), a minimally invasive imaging technique with high resolution (~10 μm), is able to visualize and monitor acute radiation‐induced esophageal damage (ARIED) in mice. We compare our findings with histopathology as the gold standard. Irradiated mice receive a single dose of 40 Gy at proximal and distal spots of the esophagus of 10.0 mm in diameter. We scan mice using OCT at two, three, and seven days post‐irradiation. In OCT analysis, we define ARIED as a presence of distorted esophageal layering, change in backscattering signal properties, or change in the esophageal wall thickness. The average esophageal wall thickness is 0.53 mm larger on OCT when ARIED is present based on histopathology. The overall sensitivity and specificity of OCT to detect ARIED compared to histopathology are 94% and 47%, respectively. However, the overall sensitivity of OCT to assess ARIED is 100% seven days post‐irradiation. We validate the capability of OCT to detect ARIED induced by high doses in mice. Nevertheless, clinical studies are required to assess the potential role of OCT to visualize ARIED in humans. 相似文献
103.
Wingless/Wnt signal transduction requires distinct initiation and amplification steps that both depend on Arrow/LRP 总被引:3,自引:1,他引:2
Members of the Wg/Wnt family provide key intercellular signals during embryonic development and in the maintenance of homeostatic processes, but critical aspects of their signal transduction pathways remain controversial. We have found that canonical Wg signaling in Drosophila involves distinct initiation and amplification steps, both of which require Arrow/LRP. Expressing a chimeric Frizzled2-Arrow protein in flies that lack endogenous Wg or Arrow showed that this construct functions as an activated Wg receptor but is deficient in signal amplification. In contrast, a chimeric Arrow protein containing the dimerization domain of Torso acted as a potent amplifier of Wg signaling but could not initiate Wg signaling on its own. The two chimeric proteins synergized, so that their co-expression largely reconstituted the signaling levels achieved by expressing Wg itself. The amplification function of Arrow/LRP appears to be particularly important for long-range signaling, and may reflect a general mechanism for potentiating signals in the shallow part of a morphogen gradient. 相似文献
104.
105.
Jip J. C. Ramakers Phillip Gienapp Marcel E. Visser 《Evolution; international journal of organic evolution》2019,73(2):175-187
Phenotypic plasticity is an important mechanism for populations to respond to fluctuating environments, yet may be insufficient to adapt to a directionally changing environment. To study whether plasticity can evolve under current climate change, we quantified selection and genetic variation in both the elevation (RNE) and slope (RNS) of the breeding time reaction norm in a long‐term (1973–2016) study population of great tits (Parus major). The optimal RNE (the caterpillar biomass peak date regressed against the temperature used as cue by great tits) changed over time, whereas the optimal RNS did not. Concordantly, we found strong directional selection on RNE, but not RNS, of egg‐laying date in the second third of the study period; this selection subsequently waned, potentially due to increased between‐year variability in optimal laying dates. We found individual and additive genetic variation in RNE but, contrary to previous studies on our population, not in RNS. The predicted and observed evolutionary change in RNE was, however, marginal, due to low heritability and the sex limitation of laying date. We conclude that adaptation to climate change can only occur via micro‐evolution of RNE, but this will necessarily be slow and potentially hampered by increased variability in phenotypic optima. 相似文献
106.
Miao Yu Tiago Castanheira Silva Andries van Opstal Stefan Romeijn Hayley A. Every Wim Jiskoot Geert-Jan Witkamp Marcel Ottens 《Biophysical journal》2019,116(4):595-609
In this study, we developed a microfluidics method, using a so-called H-cell microfluidics device, for the determination of protein diffusion coefficients at different concentrations, pHs, ionic strengths, and solvent viscosities. Protein transfer takes place in the H-cell channels between two laminarly flowing streams with each containing a different initial protein concentration. The protein diffusion coefficients are calculated based on the measured protein mass transfer, the channel dimensions, and the contact time between the two streams. The diffusion rates of lysozyme, cytochrome c, myoglobin, ovalbumin, bovine serum albumin, and etanercept were investigated. The accuracy of the presented methodology was demonstrated by comparing the measured diffusion coefficients with literature values measured under similar solvent conditions using other techniques. At low pH and ionic strength, the measured lysozyme diffusion coefficient increased with the protein concentration gradient, suggesting stronger and more frequent intermolecular interactions. At comparable concentration gradients, the measured lysozyme diffusion coefficient decreased drastically as a function of increasing ionic strength (from zero onwards) and increasing medium viscosity. Additionally, a particle tracing numerical simulation was performed to achieve a better understanding of the macromolecular displacement in the H-cell microchannels. It was found that particle transfer between the two channels tends to speed up at low ionic strength and high concentration gradient. This confirms the corresponding experimental observation of protein diffusion measured via the H-cell microfluidics. 相似文献
107.
Jacob C. Douma Jorad de Vries Erik H. Poelman Marcel Dicke Niels P.R. Anten Jochem B. Evers 《Plant, cell & environment》2019,42(3):1065-1077
Plants balance the allocation of resources between growth and defence to optimize fitness in a competitive environment. Perception of neighbour‐detection cues, such as a low ratio of red to far‐red (R:FR) radiation, activates a suite of shade‐avoidance responses that include stem elongation and upward leaf movement, whilst simultaneously downregulating defence. This downregulation is hypothesized to benefit the plant either by mediating the growth‐defence balance in favour of growth in high plant densities or, alternatively, by mediating defence of individual leaves such that those most photosynthetically productive are best protected. To test these hypotheses, we used a 3D functional–structural plant model of Brassica nigra that mechanistically simulates the interactions between plant architecture, herbivory, and the light environment. Our results show that plant‐level defence expression is a strong determinant of plant fitness and that leaf‐level defence mediation by R:FR can provide a fitness benefit in high densities. However, optimal plant‐level defence expression does not decrease monotonically with plant density, indicating that R:FR mediation of defence alone is not enough to optimize defence between densities. Therefore, assessing the ecological significance of R:FR‐mediated defence is paramount to better understand the evolution of this physiological linkage and its implications for crop breeding. 相似文献
108.
Siyu Wang Stephanie M. Reeve Graham T. Holt Adegoke A. Ojewole Marcel S. Frenkel Pablo Gainza Santosh Keshipeddy Vance G. Fowler Dennis L. Wright Bruce R. Donald 《PLoS computational biology》2022,18(2)
Antimicrobial resistance presents a significant health care crisis. The mutation F98Y in Staphylococcus aureus dihydrofolate reductase (SaDHFR) confers resistance to the clinically important antifolate trimethoprim (TMP). Propargyl-linked antifolates (PLAs), next generation DHFR inhibitors, are much more resilient than TMP against this F98Y variant, yet this F98Y substitution still reduces efficacy of these agents. Surprisingly, differences in the enantiomeric configuration at the stereogenic center of PLAs influence the isomeric state of the NADPH cofactor. To understand the molecular basis of F98Y-mediated resistance and how PLAs’ inhibition drives NADPH isomeric states, we used protein design algorithms in the osprey protein design software suite to analyze a comprehensive suite of structural, biophysical, biochemical, and computational data. Here, we present a model showing how F98Y SaDHFR exploits a different anomeric configuration of NADPH to evade certain PLAs’ inhibition, while other PLAs remain unaffected by this resistance mechanism. 相似文献
109.
Abstract An extensive literature survey of the host-range of Agrobacterium -induced neoplasms has revealed that highly susceptible plant families are accumulators of polyphenolics, whereas families assumed to be non-sensitive to the pathogen seem to lack this property. These and other results might indicate that polyphenolics play a role in the host-pathogen relationship of Agrobacterium -induced neoplasms. This hypothesis will be discussed in the light of the present knowledge of crown gall/hairy root induction and progress in plants. 相似文献
110.
The lipidation by hepatocytes of human apolipoprotein A-I occurs by both ABCA1-dependent and -independent pathways 总被引:1,自引:0,他引:1
Kiss RS McManus DC Franklin V Tan WL McKenzie A Chimini G Marcel YL 《The Journal of biological chemistry》2003,278(12):10119-10127
The pathways of hepatic intra- and peri-cellular lipidation of apolipoprotein A-I (apoA-I) were studied by infecting primary mouse hepatocytes from either apoA-I-deficient or ABCA1-deficient mice with a recombinant adenovirus expressing the human apoA-I (hapoA-I) cDNA (endo apoA-I) or incubating the hepatocytes with exogenously added hapoA-I (exo apoA-I) and examining the hapoA-I-containing lipoproteins formed. The cells, maintained in serum-free medium, were labeled with [(3)H]choline, and the cell medium was separated by fast protein liquid chromatography or immunoprecipitated to quantify labeled choline phospholipids specifically associated with hapoA-I. With the apoA-I-deficient hepatocytes, the high density lipoprotein fraction formed with endo apoA-I contained proportionally more phospholipids than that formed with exo apoA-I. However, the lipoprotein size and electrophoretic mobility and phospholipid profiles were similar for exo apoA-I and endo apoA-I. Taken together, these data demonstrate that a significant proportion of hapoA-I is secreted from hepatocytes in a phospholipidated state but that hapoA-I is also phospholipidated peri-cellularly. With primary hepatocytes from ABCA1-deficient mice, the expression and net secretion of adenoviral-generated endogenous apoA-I was unchanged compared with control mice, but (3)H-phospholipids associated with endo apoA-I and exo apoA-I decreased by 63 and 25%, respectively. The lipoprotein size and electrophoretic migration and their phospholipid profiles remained unchanged. In conclusion, we demonstrated that intracellular and peri-cellular lipidation of apoA-I represent distinct and additive pathways that may be regulated independently. Hepatocyte expression of ABCA1 is central to the lipidation of newly synthesized apoA-I but also contributes to the lipidation of exogenous apoA-I. However, a significant basal level of phospholipidation occurs in the absence of ABCA1. 相似文献