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561.
562.
J. Christiaan Keurentjes Marta Fiocco Cynthia So-Osman Ron Onstenk Ankie W. M. M. Koopman-Van Gemert Ruud G. P?ll Herman M. Kroon Thea P. M. Vliet Vlieland Rob G. Nelissen 《PloS one》2013,8(4)
Introduction
Although Total Hip and Knee Replacements (THR/TKR) improve Health-Related Quality of Life (HRQoL) at the group level, up to 30% of patients are dissatisfied after surgery due to unfulfilled expectations. We aimed to assess whether the pre-operative radiographic severity of osteoarthritis (OA) is related to the improvement in HRQoL after THR or TKR, both at the population and individual level.Methods
In this multi-center observational cohort study, HRQoL of OA patients requiring THR or TKR was measured 2 weeks before surgery and at 2–5 years follow-up, using the Short-Form 36 (SF36). Additionally, we measured patient satisfaction on a 11-point Numeric Rating Scale (NRSS). The radiographic severity of OA was classified according to Kellgren and Lawrence (KL) by an independent experienced musculoskeletal radiologist, blinded for the outcome. We compared the mean improvement and probability of a relevant improvement (defined as a patients change score≥Minimal Clinically Important Difference) between patients with mild OA (KL Grade 0–2) and severe OA (KL Grade 3+4), whilst adjusting for confounders.Results
Severe OA patients improved more and had a higher probability of a relevant improvement in physical functioning after both THR and TKR. For TKR patients with severe OA, larger improvements were found in General Health, Vitality and the Physical Component Summary Scale. The mean NRSS was also higher in severe OA TKR patients.Discussion
Patients with severe OA have a better prognosis after THR and TKR than patients with mild OA. These findings might help to prevent dissatisfaction after THR and TKR by means of patient selection or expectation management. 相似文献563.
Dirkx R Meyhi E Asselberghs S Reddy J Baes M Van Veldhoven PP 《Biochemical and biophysical research communications》2007,357(3):718-723
Beta-oxidation of carboxylates takes place both in mitochondria and peroxisomes and in each pathway parallel enzymes exist for each conversion step. In order to better define the substrate specificities of these enzymes and in particular the elusive role of peroxisomal MFP-1, hepatocyte cultures from mice with peroxisomal gene knockouts were used to assess the consequences on substrate degradation. Hepatocytes from mice with liver selective elimination of peroxisomes displayed severely impaired oxidation of 2-methylhexadecanoic acid, the bile acid intermediate trihydroxycholestanoic acid (THCA), and tetradecanedioic acid. In contrast, mitochondrial beta-oxidation rates of palmitate were doubled, despite the severely affected inner mitochondrial membrane. As expected, beta-oxidation of the branched chain compounds 2-methylhexadecanoic acid and THCA was reduced in hepatocytes from mice with inactivation of MFP-2. More surprisingly, dicarboxylic fatty acid oxidation was impaired in MFP-1 but not in MFP-2 knockout hepatocytes, indicating that MFP-1 might play more than an obsolete role in peroxisomal beta-oxidation. 相似文献
564.
565.
566.
Jose L. Lozano-Torres Ruud H. P. Wilbers Sonja Warmerdam Anna Finkers-Tomczak Amalia Diaz-Granados Casper C. van Schaik Johannes Helder Jaap Bakker Aska Goverse Arjen Schots Geert Smant 《PLoS pathogens》2014,10(12)
Despite causing considerable damage to host tissue during the onset of parasitism, nematodes establish remarkably persistent infections in both animals and plants. It is thought that an elaborate repertoire of effector proteins in nematode secretions suppresses damage-triggered immune responses of the host. However, the nature and mode of action of most immunomodulatory compounds in nematode secretions are not well understood. Here, we show that venom allergen-like proteins of plant-parasitic nematodes selectively suppress host immunity mediated by surface-localized immune receptors. Venom allergen-like proteins are uniquely conserved in secretions of all animal- and plant-parasitic nematodes studied to date, but their role during the onset of parasitism has thus far remained elusive. Knocking-down the expression of the venom allergen-like protein Gr-VAP1 severely hampered the infectivity of the potato cyst nematode Globodera rostochiensis. By contrast, heterologous expression of Gr-VAP1 and two other venom allergen-like proteins from the beet cyst nematode Heterodera schachtii in plants resulted in the loss of basal immunity to multiple unrelated pathogens. The modulation of basal immunity by ectopic venom allergen-like proteins in Arabidopsis thaliana involved extracellular protease-based host defenses and non-photochemical quenching in chloroplasts. Non-photochemical quenching regulates the initiation of the defense-related programmed cell death, the onset of which was commonly suppressed by venom allergen-like proteins from G. rostochiensis, H. schachtii, and the root-knot nematode Meloidogyne incognita. Surprisingly, these venom allergen-like proteins only affected the programmed cell death mediated by surface-localized immune receptors. Furthermore, the delivery of venom allergen-like proteins into host tissue coincides with the enzymatic breakdown of plant cell walls by migratory nematodes. We, therefore, conclude that parasitic nematodes most likely utilize venom allergen-like proteins to suppress the activation of defenses by immunogenic breakdown products in damaged host tissue. 相似文献
567.
Dennis F. G. Remst Esmeralda N. Blaney Davidson Elly L. Vitters Ruud A. Bank Wim B. van den Berg Peter M. van der Kraan 《Cell and tissue research》2014,355(1):163-171
Lysyl hydroxylase 2b (LH2b) is known to increase pyridinoline cross-links, making collagen less susceptible to enzymatic degradation. Previously, we observed a relationship between LH2b and osteoarthritis-related fibrosis in murine knee joint. For this study, we investigate if transforming growth factor-beta (TGF-ß) and connective tissue growth factor (CTGF) regulate procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2) (gene encoding LH2b) and LH2b expression differently in osteoarthritic human synovial fibroblasts (hSF). Furthermore, we investigate via which TGF-ß route (Smad2/3P or Smad1/5/8P) LH2b is regulated, to explore options to inhibit LH2b during fibrosis. To answer these questions, fibroblasts were isolated from knee joints of osteoarthritis patients. The hSF were stimulated with TGF-ß with or without a kinase inhibitor of ALK4/5/7 (SB-505124) or ALK1/2/3/6 (dorsomorphin). TGF-ß, CTGF, constitutively active (ca)ALK1 and caALK5 were adenovirally overexpressed in hSF. The gene expression levels of PLOD1/2/3, CTGF and COL1A1 were analyzed with Q-PCR. LH2 protein levels were determined with western blot. As expected, TGF-ß induced PLOD2/LH2 expression in hSF, whereas CTGF did not. PLOD1 and PLOD3 were not affected by either TGF-ß or CTGF. SB-505124 prevented the induction of TGF-ß-induced PLOD2, CTGF and COL1A1. Surprisingly, dorsomorphin completely blocked the induction of CTGF and COL1A1, whereas TGF-ß-induced PLOD2 was only slightly reduced. Overexpression of caALK5 in osteoarthritic hSF significantly induced PLOD2/LH2 expression, whereas caALK1 had no effect. We showed, in osteoarthritic hSF, that TGF-ß induced PLOD2/LH2 via ALK5 Smad2/3P. This elevation of LH2b in osteoarthritic hSF makes LH2b an interesting target to interfere with osteoarthritis-related persistent fibrosis. 相似文献
568.
Marco Madella Juan José García-Granero Welmoed A. Out Philippa Ryan Donatella Usai 《PloS one》2014,9(10)
The study of plant exploitation and early use of cereals in Africa has seen over the years a great input from charred and desiccated macrobotanical remains. This paper presents the results of one of the few examples in Africa of microbotanical analyses. Three grave contexts of phytolith-rich deposits and the dental calculus of 20 individuals were analysed from two Neolithic cemeteries in North and Central Sudan. The radiocarbon-dated phytoliths from the burial samples show the presence of Near East domestic cereals in Northern Sudan at least 7000 years ago. Phytoliths also indicate the exploitation of wild, savannah-adapted millets in Central Sudan between 7500 and 6500 years ago. The calculus samples contained starch grains from wheat/barley, pulses and millets, as well as panicoid phytoliths. This evidence shows that Near East domestic cereals were consumed in Northern Africa at least 500 years earlier than previously thought. 相似文献
569.
Monika Althaus Yvonne Groen Lutske van der Schaft Ruud B. Minderaa Oliver Tucha Lambertus J. M. Mulder Albertus A. Wijers 《PloS one》2014,9(10)
Objective
This study investigated the effect of social relevance in affective pictures on two orienting responses, i.e. the evoked cardiac response (ECR), and a long latency cortical evoked potential (LPP) and whether this effect would differ between males and females. Assuming that orienting to affective social information is fundamental to experiencing affective empathy, associations between self-report measures of empathy and the two orienting responses were investigated.Method
ECRs were obtained from 34 female and 30 male students, and LPPs from 25 female and 27 male students viewing 414 pictures from the International Affective Picture System. Pictures portrayed pleasant, unpleasant and neutral scenes with and without humans.Results
Both the ECR and LPP showed the largest response to pictures with humans in unpleasant situations. For both measures, the responses to pictures with humans correlated with self-report measures of empathy. While we found a greater male than female responsiveness to the pictures without humans in the ECR, a greater female than male responsiveness was observed in the LPP response to pictures with humans.Conclusion and Significance
The sensitivity of these orienting responses to social relevance and their differential contribution to the prediction of individual differences underline the validity of their combined use in clinical studies investigating individuals with social disabilities. 相似文献570.
Sylwia Kuc Maria P. H. Koster Jeroen L. A. Pennings Thomas Hankemeier Ruud Berger Amy C. Harms Adrie D. Dane Peter C. J. I. Schielen Gerard H. A. Visser Rob J. Vreeken 《PloS one》2014,9(5)