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Growing research effort has shown that physical enrichment (PE) can improve fish welfare and research validity. However, the inclusion of PE does not always result in positive effects and conflicting findings have highlighted the many nuances involved. Effects are known to depend on species and life stage tested, but effects may also vary with differences in the specific items used as enrichment between and within studies. Reporting fine-scale characteristics of items used as enrichment in studies may help to reveal these factors. We conducted a survey of PE-focused studies published in the last 5 years to examine the current state of methodological reporting. The survey results suggest that some aspects of enrichment are not adequately detailed. For example, the amount and dimensions of objects used as enrichment were frequently omitted. Similarly, the ecological relevance, or other justification, for enrichment items was frequently not made explicit. Focusing on ecologically relevant aspects of PE and increasing the level of detail reported in studies may benefit future work and we propose a framework with the acronym DETAILS ( D imensions, E cological rationale, T iming of enrichment, A mount, I nputs, L ighting and S ocial environment). We outline the potential importance of each of the elements of this framework with the hope it may aid in the level of reporting and standardization across studies, ultimately aiding the search for more beneficial types of PE and the development of our understanding and ability to improve the welfare of captive fish and promote more biologically relevant behaviour. 相似文献
43.
Laura A. Mike Andrew J. Stark Valerie S. Forsyth Jay Vornhagen Sara N. Smith Michael A. Bachman Harry L. T. Mobley 《PLoS pathogens》2021,17(3)
Hypervirulent K. pneumoniae (hvKp) is a distinct pathotype that causes invasive community-acquired infections in healthy individuals. Hypermucoviscosity (hmv) is a major phenotype associated with hvKp characterized by copious capsule production and poor sedimentation. Dissecting the individual functions of CPS production and hmv in hvKp has been hindered by the conflation of these two properties. Although hmv requires capsular polysaccharide (CPS) biosynthesis, other cellular factors may also be required and some fitness phenotypes ascribed to CPS may be distinctly attributed to hmv. To address this challenge, we systematically identified genes that impact capsule and hmv. We generated a condensed, ordered transposon library in hypervirulent strain KPPR1, then evaluated the CPS production and hmv phenotypes of the 3,733 transposon mutants, representing 72% of all open reading frames in the genome. We employed forward and reverse genetic screens to evaluate effects of novel and known genes on CPS biosynthesis and hmv. These screens expand our understanding of core genes that coordinate CPS biosynthesis and hmv, as well as identify central metabolism genes that distinctly impact CPS biosynthesis or hmv, specifically those related to purine metabolism, pyruvate metabolism and the TCA cycle. Six representative mutants, with varying effect on CPS biosynthesis and hmv, were evaluated for their impact on CPS thickness, serum resistance, host cell association, and fitness in a murine model of disseminating pneumonia. Altogether, these data demonstrate that hmv requires both CPS biosynthesis and other cellular factors, and that hmv and CPS may serve distinct functions during pathogenesis. The integration of hmv and CPS to the metabolic status of the cell suggests that hvKp may require certain nutrients to specifically cause deep tissue infections. 相似文献
44.
Ecosystems - In arid environments, shade provided by vegetation forms the crux of many facilitation pathways by providing other organisms with relief from high levels of solar radiation and extreme... 相似文献
45.
Abstract Taxonomic representation and regional distribution patterns of taxa, life forms, and defence mechanisms of the succulent flora of South Africa and Namibia are quantified and discussed in relation to physical and biotic factors. Habitats are investigated and for each region centres of succulent species richness are pointed out. 相似文献
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David F Ten Cate Jolanda J Luime Nanno Swen Andreas H Gerards Mike H De Jager Natalja M Basoski Johanna MW Hazes Cees J Haagsma Johannes WG Jacobs 《Arthritis research & therapy》2013,15(1):R4
Introduction
Ultrasonography (US) might have an added value to clinical examination in diagnosing early rheumatoid arthritis (RA) and assessing remission of RA. We aimed to clarify the added value of US in RA in these situations performing a systematic review.Methods
A systematic literature search was performed for RA, US, diagnosis and remission. Methodological quality was assessed; the wide variability in the design of studies prohibited pooling of results.Results
Six papers on the added value of US diagnosing early RA were found, in which at least bilateral metacarpophalangeal (MCP), wrists and metatarsophalangeal (MTP) joints were scanned. Compared to clinical examination, US was superior with regard to detecting synovitis and predicting progression to persistent arthritis or RA. Eleven papers on assessing remission were identified, in which at least the wrist and the MCP joints of the dominant hand were scanned. Often US detected inflammation in patients clinically in remission, irrespective of the remission criteria used. Power Doppler signs of synovitis predicted X-ray progression and future flare in patients clinically in remission.Conclusions
US appears to have added value to clinical examination for diagnosing of RA when scanning at least MCP, wrist and MTP joints, and, when evaluating remission of RA, scanning at least wrist and MCP joints of the dominant hand. For both purposes primarily power Doppler US might be used since its results are less equivocal than those of greyscale US. 相似文献49.
Rebecca E. Williams Lisa Cottrell Matthew Jacobsen Lasantha R. Bandara Mike D. Kelly Sandy Kennedy 《Biomarkers》2013,18(6):472-490
N-Phenylanthranilic acid (NPAA) causes renal papillary necrosis (RPN) in the rat following repeated oral dosing. Non-invasive early detection of RPN is difficult, but a number of potential biomarkers have been investigated, including phospholipid and uronic acid excretion. This study used 1H-nuclear magnetic resonance (NMR) spectroscopic analysis of urine to investigate urinary metabolic perturbations occurring in the rat following exposure to NPAA. Male Alderley Park rats received NPAA (300, 500 or 700?mg?kg?1?day?1 orally) for 7?days, and urine was collected on days 7–8, 14–15, 21–22 and 28–29. In a separate study, urine was collected on days 1–2, 3–4, 5–6 and 7–8 from rats receiving 500?mg?kg?1?day?1. Samples were analysed by 1H NMR spectroscopy combined with multivariate data analysis and clinical chemistry. Histopathology and clinical chemistry analysis of terminal blood samples was carried out following termination on days 4, 6, 8 and 29 (4?week time course) and days 2, 4, 6 and 8 (8?day study). Urine analysis revealed a marked, though variable, excretion of β-hydroxybutyrate, acetoacetate and acetone (ketone bodies) seen on days 3–4, 5–6 and 7–8 of the study. It is postulated that the ketonuria might be secondary to an alteration in fatty acid metabolism due to inhibition of prostaglandin synthesis. In addition, an elevation in urinary ascorbate was observed during the first 8?days of the study. Ascorbate is considered to be a biomarker of hepatic response, probably reflecting an increased hepatic activity due to glucuronidation of NPAA. 相似文献
50.
Steven Wainwright Clare Williams Mike Michael Bobbie Farsides Alan Cribb 《New genetics and society》2013,32(3):251-254
Abstrat In this paper we discuss genetic discourses and practices in stem cell science. We report on how biomedical scientists, in both the UK and the USA, view the scientific literature and their own experimental research in the emerging field of human embryonic stem (hES) cells. We focus on the genetic manipulation of stem cells to make specialized (beta) cells as a potential cure for diabetes. We draw on Gieryn's notion of boundary work as an analytical motif, and suggest this is a productive way to theorize boundary crossings in the shifting landscapes of expectations in the field of new medical technologies. We argue that initial expectations of a revolution in regenerative medicine have been damped down by the difficulties of making insulin producing pancreatic beta cells from stem cells. We contend the consequent shifts in expectations have led to the emergence of other more radical experimental strategies (such as using oncogenes) in the search for potential cures for Type 1 diabetes. In conclusion, we argue that regenerative medicine is a fruitful example of the shaping of contested biomedical landscapes and we contend that embryonic stem cells are a productive case study of the interactions between genetics, science and society. 相似文献