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141.
I Prieto-Potín JA Roman-Blas MJ Martínez-Calatrava R Gómez R Largo Gabriel Herrero-Beaumont 《Arthritis research & therapy》2013,15(4):R81
Objective
The aim of this study was to determine whether hypercholesterolemia increases articular damage in a rabbit model of chronic arthritis.Methods
Hypercholesterolemia was induced in 18 rabbits by administrating a high-fat diet (HFD). Fifteen rabbits were fed normal chow as controls. Chronic antigen-induced arthritis (AIA) was induced in half of the HFD and control rabbits, previously immunized, by intra-articular injections of ovalbumin. After sacrifice, lipid and systemic inflammation markers were analyzed in blood serum. Synovium was analyzed by Krenn score, multinucleated cell counting, immunohistochemistry of RAM11 and CD31, and TNF-α and macrophage chemoattractant protein-1 (MCP-1) gene expression. Active bone resorption was assessed by protein expression of receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG) and quantification of cathepsin K, contact surface and the invasive area of pannus into bone.Results
Rabbits receiving the HFD showed higher total serum cholesterol, HDL, triglycerides and CRP levels than rabbits fed a normal diet. Synovitis score was increased in HFD, and particularly in AIA and AIA + HFD groups. AIA + HFD synovium was characterized by a massive infiltration of RAM11+ cells, higher presence of multinucleated foam cells and bigger vascularization than AIA. Cathepsin K+ osteoclasts and the contact surface of bone resorbing pannus were also increased in rabbits with AIA + HFD compared with AIA alone. Synovial TNF-α and MCP-1 gene expression was increased in AIA and HFD rabbits compared with healthy animals. RANKL protein expression in AIA and AIA + HFD groups was higher compared with either HFD or normal groups.Conclusions
This experimental model demonstrates that hypercholesterolemia increments joint tissue damage in chronic arthritis, with foam macrophages being key players in this process. 相似文献142.
Vermeij TA Edelbroek PM 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,857(1):40-46
A rapid, simple and robust method is presented for the simultaneous determination of seven antiepileptic drugs (AEDs), including primidone, phenobarbital, phenytoin, carbamazepine with its two major metabolites carbamazepine-10,11-epoxide and carbamazepine-10,11-(trans)-dihydrodiol and the new AEDs lamotrigine, hydroxycarbazepine (active metabolite of oxcarbazepine) and zonisamide in serum by high performance liquid chromatography (HPLC)-diode array detector (DAD). After solid-phase extraction, separation is achieved on an Alltima 3C18 analytical column using isocratic elution with a mixture of acetonitrile, methanol and phosphate buffer at 45 degrees C. The method is exhaustively validated, including experimental design in combination with statistical evaluation (ANOVA) to study the robustness of chromatography and sample preparation. Commonly co-administered antiepileptic drugs do not interfere with the method. Intra-day precision (RSD<1.9%), linearity, lower limit of quantitation (LOQ<0.065 mg/l) and robustness make the method suitable for daily therapeutic drug monitoring and pharmacokinetic studies. 相似文献
143.
Joost den Haan Jef Huisman Friso Dekker Jacomina L. ten Brinke Amanda K. Ford Jan van Ooijen Fleur C. van Duyl Mark J. A. Vermeij Petra M. Visser 《PloS one》2013,8(7)
Background
Rapid determination of which nutrients limit the primary production of macroalgae and seagrasses is vital for understanding the impacts of eutrophication on marine and freshwater ecosystems. However, current methods to assess nutrient limitation are often cumbersome and time consuming. For phytoplankton, a rapid method has been described based on short-term changes in chlorophyll fluorescence upon nutrient addition, also known as Nutrient-Induced Fluorescence Transients (NIFTs). Thus far, though, the NIFT technique was not well suited for macroalgae and seagrasses.Methodology & Principal Findings
We developed a new experimental setup so that the NIFT technique can be used to assess nutrient limitation of benthic macroalgae and seagrasses. We first tested the applicability of the technique on sea lettuce (Ulva lactuca) cultured in the laboratory on nutrient-enriched medium without either nitrogen or phosphorus. Addition of the limiting nutrient resulted in a characteristic change in the fluorescence signal, whereas addition of non-limiting nutrients did not yield a response. Next, we applied the NIFT technique to field samples of the encrusting fan-leaf alga Lobophora variegata, one of the key algal species often involved in the degradation of coral reef ecosystems. The results pointed at co-limitation of L. variegata by phosphorus and nitrogen, although it responded more strongly to phosphate than to nitrate and ammonium addition. For turtle grass (Thalassia testudinum) we found the opposite result, with a stronger NIFT response to nitrate and ammonium than to phosphate.Conclusions & Significance
Our extension of the NIFT technique offers an easy and fast method (30–60 min per sample) to determine nutrient limitation of macroalgae and seagrasses. We successfully applied this technique to macroalgae on coral reef ecosystems and to seagrass in a tropical inner bay, and foresee wider application to other aquatic plants, and to other marine and freshwater ecosystems. 相似文献144.
Arno Wegkamp Astrid E Mars Magda Faijes Douwe Molenaar Ric CH de Vos Sebastian MJ Klaus Andrew D Hanson Willem M de Vos Eddy J Smid 《Microbial cell factories》2010,9(1):100
Background
Using a functional genomics approach we addressed the impact of folate overproduction on metabolite formation and gene expression in Lactobacillus plantarum WCFS1. We focused specifically on the mechanism that reduces growth rates in folate-overproducing cells. 相似文献145.
Laura Sheard Nat MJ Wright Clive E Adams Nicole Bound Bruno Rushforth Roger Hart Charlotte NE Tompkins 《Trials》2009,10(1):1-5
Many research-funding agencies now require open access to the results of research they have funded, and some also require that researchers make available the raw data generated from that research. Similarly, the journal Trials aims to address inadequate reporting in randomised controlled trials, and in order to fulfil this objective, the journal is working with the scientific and publishing communities to try to establish best practice for publishing raw data from clinical trials in peer-reviewed biomedical journals. Common issues encountered when considering raw data for publication include patient privacy – unless explicit consent for publication is obtained – and ownership, but agreed-upon policies for tackling these concerns do not appear to be addressed in the guidance or mandates currently established. Potential next steps for journal editors and publishers, ethics committees, research-funding agencies, and researchers are proposed, and alternatives to journal publication, such as restricted access repositories, are outlined. 相似文献
146.
Survival and settlement success of coral planulae: independent and synergistic effects of macroalgae and microbes 总被引:1,自引:0,他引:1
M. J. A. Vermeij J. E. Smith C. M. Smith R. Vega Thurber S. A. Sandin 《Oecologia》2009,159(2):325-336
Restoration of degraded coral reef communities is dependent on successful recruitment and survival of new coral planulae.
Degraded reefs are often characterized by high cover of fleshy algae and high microbial densities, complemented by low abundance
of coral and coral recruits. Here, we investigated how the presence and abundance of macroalgae and microbes affected recruitment
success of a common Hawaiian coral. We found that the presence of algae reduced survivorship and settlement success of planulae.
With the addition of the broad-spectrum antibiotic, ampicillin, these negative effects were reversed, suggesting that algae
indirectly cause planular mortality by enhancing microbial concentrations or by weakening the coral’s resistance to microbial
infections. Algae further reduced recruitment success of corals as planulae preferentially settled on algal surfaces, but
later suffered 100% mortality. In contrast to survival, settlement was unsuccessful in treatments containing antibiotics,
suggesting that benthic microbes may be necessary to induce settlement. These experiments highlight potential complex interactions
that govern the relationships between microbes, algae and corals and emphasize the importance of microbial dynamics in coral
reef ecology and restoration.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
147.
The effect of nutrient availability on growth, survival, and photosynthetic performance of drifting fragments of the invasive
red alga Hypnea musciformis was studied in Maui (Hawaii), where this species smothers native reef communities and forms localized blooms. H. musciformis does not sexually reproduce in Hawaii and drifting fragments represent the only pathway by which H. musciformis can disperse and invade new areas. Growth rates decreased with age and approached zero when fragments aged 32 days. Increased
nutrient availability did not result in increased relative growth rates during this period. In contrast to growth, photosynthetic
performance remained unaffected through time and showed no clear relationship with nutrient availability. Increased nutrient
availability increased fragment survival and fragments survived for >2 months in the high nutrient treatment (3.0 μmolPO4 + 30.0 μmolNH4). This indicates that increased nutrient availability increases the dispersal potential of H. musciformis. Low growth rates of drifting Hypnea fragments increased recruitment success since attachment success of this epiphytic species decreased with increasing fragment
size. H. musciformis thus uses resources for survival and maintenance rather than growth, resulting in long competency periods and optimal recruitment,
which likely contribute to its success as an invader of Hawaiian reef communities. 相似文献
148.
Tracey E Toms Vasileios F Panoulas Holly John Karen MJ Douglas George D Kitas 《Arthritis research & therapy》2009,11(4):R110-10
Introduction
The metabolic syndrome (MetS) may contribute to the excess cardiovascular burden observed in rheumatoid arthritis (RA). The prevalence and associations of the MetS in RA remain uncertain: systemic inflammation and anti-rheumatic therapy may contribute. Methotrexate (MTX) use has recently been linked to a reduced presence of MetS, via an assumed generic anti-inflammatory mechanism. We aimed to: assess the prevalence of the MetS in RA; identify factors that associate with its presence; and assess their interaction with the potential influence of MTX. 相似文献149.
150.
Chloe?KB?Mortimer Tansy?M?Peters Saheer?E?Gharbia Julie?MJ?Logan Catherine?ArnoldEmail author 《BMC microbiology》2004,4(1):31