Kennis op de akker: toepassing in management tools

Om de positie van de Nederlandse akkerbouw en vollegrondsgroenteteelt te behouden moet er een transitie plaatsvinden naar een duurzame procesgeoriënteerde bedrijfsvoering, gebaseerd op actuele informatie en kennis, waarbij managementondersteunende systemen en ICT kunnen helpen. Het artikel presenteert de resultaten van een programmeringsstudie, die geresulteerd heeft in een voorstel voor een programma om aan deze transitie te gaan werke

Optimizing the therapeutic index of liposomal glucocorticoids in experimental arthritis.

Item does not contain fulltextSmall-sized (less than 150 nm) long-circulating liposomes (LCL) may be useful as drug-targeting vehicles for anti-inflammatory agents in arthritis, since they selectively home at inflamed joints after i.v. administration. Previously it was shown in experimental arthritis that encapsulation of glucocorticoids (GC) as water-soluble phosphate esters in PEG-liposomes resulted in a strong improvement of the anti-inflammatory effect as compared to the free drug. In the present study, we compared the therapeutic activity and adverse effects induced by 3 different GC encapsulated in LCL in an attempt to further optimize the therapeutic index of liposomal GC in arthritis. Our data showed that with GC (dexamethasone, budesonide) of higher potency than prednisolone, the therapeutic activity of liposomal GC can be increased. However, side effects at the level of body weight and hyperglycemia were noted, related to the sustained free GC level observed after injection of the liposomal GC. An inverse relationship with the clearance rate of the free GC in question was shown. This study stresses the importance of a high clearance rate of the GC to be encapsulated for achieving a maximal therapeutic index with liposomal GC. Therefore high-clearance GC, which until now are only applied in local treatment approaches, may be very useful for the development of novel, highly effective anti-inflammatory preparations for systemic treatment of inflammatory disorders

Chemogenomics approaches for receptor deorphanization and extensions of the chemogenomics concept to phenotypic space

Chemogenomic approaches, which link ligand chemistry to bioactivity against targets (and, by extension, to phenotypes) are becoming more and more important due to the increasing number of bioactivity data available both in proprietary databases as well as in the public domain. In this article we review chemogenomics approaches applied in four different domains: Firstly, due to the relationship between protein targets from which an approximate relation between their respective bioactive ligands can be inferred, we investigate the extent to which chemogenomics approaches can be applied to receptor deorphanization. In this case it was found that by using knowledge about active compounds of related proteins, in 93% of all cases enrichment better than random could be obtained. Secondly, we analyze different chemin-formatics analysis methods with respect to their behavior in chemogenomics studies, such as subgraph mining and Baye-sian models. Thirdly, we illustrate how chemogenomics, in its particular flavor of 'proteochemometrics', can be applied to extrapolate bioactivity predictions from given data points to related targets. Finally, we extend the concept of 'chemoge-nomics' approaches, relating ligand chemistry to bioactivity against related targets, into phenotypic space which then falls into the area of 'chemical genomics' and 'chemical genetics'; given that this is very often the desired endpoint of approaches in not only the pharmaceutical industry, but also in academic probe discovery, this is often the endpoint the experimental scientist is most interested in. © 2011 Bentham Science Publishers

Assessment of tissue viability following amputation surgery using near-infrared fluorescence imaging with indocyanine green

Background: Patients with chronic limb threatening ischemia have a risk of undergoing a major amputation within 1 year of nearly 30% with a substantial risk of re-amputation since wound healing is often impaired. Quantitative assessment of regional tissue viability following amputation surgery can identify patients at risk for impaired wound healing. In quantification of regional tissue perfusion, near-infrared (NIR) fluorescence imaging using Indocyanine Green (ICG) seems promising. Methods: This pilot study included adult patients undergoing lower extremity amputation surgery due to peripheral artery disease or diabetes mellitus. ICG NIR fluorescence imaging was performed within 5 days following amputation surgery using the Quest Spectrum Platform (R). Following intravenous administration of ICG, the NIR fluorescence intensity of the amputation wound was recorded for 10 minutes. The NIR fluorescence intensity videos were analyzed and if a fluorescence deficit was observed, this region was marked as "low fluorescence." All other regions were marked as "normal fluorescence." Results: Successful ICG NIR fluorescence imaging was performed in 10 patients undergoing a total of 15 amputations. No "low fluorescence" regions were observed in 11 out of 15 amputation wounds. In 10 out of these 11 amputations, no wound healing problems occurred during followup. Regions with "low fluorescence" were observed in 4 amputation wounds. Impaired wound healing corresponding to these regions was observed in all wounds and a re-amputation was necessary in 3 out of 4. When observing time-related parameters, regions with low fluorescence had a significantly longer time to maximum intensity (113 seconds vs. 32 seconds, P = 0.003) and a significantly lesser decline in outflow after five minutes (80.3% vs. 57.0%, P = 0.003). Conclusions: ICG NIR fluorescence imaging was able to predict postoperative skin necrosis in all four cases. Quantitative assessment of regional perfusion remains challenging due to influencing factors on the NIR fluorescence intensity signal, including camera angle, camera distance and ICG dosage. This was also observed in this study, contributing to a large variety in fluorescence intensity parameters among patients. To provide surgeons with reliable NIR fluorescence cut-off values for prediction of wound healing, prospective studies on the intraoperative use of this technique are required. The potential prediction of wound healing using ICG NIR fluorescence imaging will have a huge impact on patient mortality, morbidity as well as the burden of amputation surgery on health care.Vascular Surger

Assessment of tissue viability following amputation surgery using near-infrared fluorescence imaging with indocyanine green

Background: Patients with chronic limb threatening ischemia have a risk of undergoing a major amputation within 1 year of nearly 30% with a substantial risk of re-amputation since wound healing is often impaired. Quantitative assessment of regional tissue viability following amputation surgery can identify patients at risk for impaired wound healing. In quantification of regional tissue perfusion, near-infrared (NIR) fluorescence imaging using Indocyanine Green (ICG) seems promising. Methods: This pilot study included adult patients undergoing lower extremity amputation surgery due to peripheral artery disease or diabetes mellitus. ICG NIR fluorescence imaging was performed within 5 days following amputation surgery using the Quest Spectrum Platform (R). Following intravenous administration of ICG, the NIR fluorescence intensity of the amputation wound was recorded for 10 minutes. The NIR fluorescence intensity videos were analyzed and if a fluorescence deficit was observed, this region was marked as "low fluorescence." All other regions were marked as "normal fluorescence." Results: Successful ICG NIR fluorescence imaging was performed in 10 patients undergoing a total of 15 amputations. No "low fluorescence" regions were observed in 11 out of 15 amputation wounds. In 10 out of these 11 amputations, no wound healing problems occurred during followup. Regions with "low fluorescence" were observed in 4 amputation wounds. Impaired wound healing corresponding to these regions was observed in all wounds and a re-amputation was necessary in 3 out of 4. When observing time-related parameters, regions with low fluorescence had a significantly longer time to maximum intensity (113 seconds vs. 32 seconds, P = 0.003) and a significantly lesser decline in outflow after five minutes (80.3% vs. 57.0%, P = 0.003). Conclusions: ICG NIR fluorescence imaging was able to predict postoperative skin necrosis in all four cases. Quantitative assessment of regional perfusion remains challenging due to influencing factors on the NIR fluorescence intensity signal, including camera angle, camera distance and ICG dosage. This was also observed in this study, contributing to a large variety in fluorescence intensity parameters among patients. To provide surgeons with reliable NIR fluorescence cut-off values for prediction of wound healing, prospective studies on the intraoperative use of this technique are required. The potential prediction of wound healing using ICG NIR fluorescence imaging will have a huge impact on patient mortality, morbidity as well as the burden of amputation surgery on health care.</p

Charting a new course in healthcare: early-stage AI algorithm registration to enhance trust and transparency

AI holds the potential to transform healthcare, promising improvements in patient care. Yet, realizing this potential is hampered by over-reliance on limited datasets and a lack of transparency in validation processes. To overcome these obstacles, we advocate the creation of a detailed registry for AI algorithms. This registry would document the development, training, and validation of AI models, ensuring scientific integrity and transparency. Additionally, it would serve as a platform for peer review and ethical oversight. By bridging the gap between scientific validation and regulatory approval, such as by the FDA, we aim to enhance the integrity and trustworthiness of AI applications in healthcare.Information and Communication TechnologyEthics & Philosophy of Technolog

The digestive performance of mammalian herbivores: why big may not be that much better

1. A traditional approach to the nutritional ecology of herbivores is that larger animals can tolerate a diet of lesser quality due to a higher digestive efficiency bestowed on them by comparatively long ingesta retention times and lower relative energy requirements. 2. There are important physiological disadvantages that larger animals must compensate for, namely a lower gut surface : gut volume ratio, larger ingesta particle size and greater losses of faecal bacterial material due to more fermentation. Compensating adaptations could include an increased surface enlargement in larger animals, increased absorption rates per unit of gut surface, and increased gut motility to enhance mixing of ingesta. 3. A lower surface : volume ratio, particularly in sacciform forestomach structures, could be a reason for the fact that methane production is of significant scope mainly in large herbivores and not in small herbivores with comparably long retention times; in the latter, the substrate for methanogenesis – the volatile fatty acids – could be absorbed faster due to a more favourable gut surface : volume ratio. 4. Existing data suggest that in herbivores, an increase in fibre digestibility is not necessarily accompanied by an increase in overall apparent dry matter digestibility. This indicates a comparative decrease of the apparent digestibility of non-fibre material, either due to a lesser utilization of non-fibre substrate or an increased loss of endogenous/bacterial substance. Quantitative research on these mechanisms is warranted in order to evaluate whether an increase in body size represents a net increase of digestive efficiency or just a shift of digestive focus

INTENTIONAL COMMUNITIES IN RURAL SPACES

In this paper, we focus on intentional communities in the Western world. These communities consist of a variety of groups, with different characteristics, ideologies and motivations. Examples are eco-villages, religious communities and communities of lesbians. These groups intend, at least to some extent, to withdraw from mainstream urban society, challenging norms of urban life, e.g. wasteful behaviour, stressful lives or heterosexual stereotypes, and create their own places in rural areas. Key questions that we seek to address in the paper are: What types of intentional communities can be identified? To what extent are intentional communities withdrawn from the rural areas in which they are established? We attempt to answer these through discussing the results of a survey among 496 communities. Furthermore, we describe an example of the ecological type of community, since these communities are most explicitly challenging urban norms and values. Copyright (c) 2007 by the Royal Dutch Geographical Society KNAG.