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51.
Cristiano S. Moura Michal Abrahamowicz Marie-Eve Beauchamp Diane Lacaille Yishu Wang Gilles Boire Paul R. Fortin Louis Bessette Claire Bombardier Jessica Widdifield John G. Hanly Debbie Feldman Walter Maksymowych Christine Peschken Cheryl Barnabe Steve Edworthy Sasha Bernatsky CAN-AIM 《Arthritis research & therapy》2015,17(1)
IntroductionUse of disease-modifying anti-rheumatic drugs (DMARDs) in rheumatoid arthritis (RA) may prevent joint damage and potentially reduce joint replacement surgeries. We assessed the association between RA drug use and joint replacement in Quebec, Canada.MethodsA cohort of new-onset RA patients was identified from Quebec’s physician billing and hospitalization databases from 2002–2011. The outcome was defined using procedure codes submitted by orthopedic surgeons. Medication use was obtained from pharmacy databases. We used alternative Cox regression models with time-dependent variables measuring the cumulative effects of past use during different time windows (one model focussing on the first year after cohort entry) for methotrexate (MTX), and other DMARDs. Models were adjusted for baseline sociodemographics, co-morbidity and prior health service use, time-dependent cumulative use of other drugs (anti-tumor necrosis factor [anti-TNF] agents, other biologics, cyclooxygenase-2 inhibitors [COXIBs], nonselective nonsteroidal antiinflammatory drugs [NSAIDs], and systemic steroids), and markers of disease severity.ResultsDuring follow-up, 608 joint replacements occurred among 11,333 patients (median follow-up: 4.6 years). The best-fitting model relied on the cumulative early use (within the first year after cohort entry) of MTX and of other DMARDs, with an interaction between MTX and other DMARDs. In this model, greater exposure within the first year, to either MTX (adjusted hazard ratio, HR = 0.95 per 1 month, 95 % confidence interval, 95 % CI 0.93-0.97) or other DMARDs (HR = 0.97, 95 % CI 0.95-0.99) was associated with longer time to joint replacement.ConclusionsOur results suggest that longer exposure to either methotrexate (MTX) or other DMARDs within the first year after RA diagnosis is associated with longer time to joint replacement surgery.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0713-3) contains supplementary material, which is available to authorized users. 相似文献52.
Cristiano S. Mota Maria G. Rivas Carlos D. Brondino Isabel Moura José J. G. Moura Pablo J. González Nuno M. F. S. A. Cerqueira 《Journal of biological inorganic chemistry》2011,16(8):1255-1268
Metal-dependent formate dehydrogenases (Fdh) from prokaryotic organisms are members of the dimethyl sulfoxide reductase family
of mononuclear molybdenum-containing and tungsten-containing enzymes. Fdhs catalyze the oxidation of the formate anion to
carbon dioxide in a redox reaction that involves the transfer of two electrons from the substrate to the active site. The
active site in the oxidized state comprises a hexacoordinated molybdenum or tungsten ion in a distorted trigonal prismatic
geometry. Using this structural model, we calculated the catalytic mechanism of Fdh through density functional theory tools.
The simulated mechanism was correlated with the experimental kinetic properties of three different Fdhs isolated from three
different Desulfovibrio species. Our studies indicate that the C–H bond break is an event involved in the rate-limiting step of the catalytic cycle.
The role in catalysis of conserved amino acid residues involved in metal coordination and near the metal active site is discussed
on the basis of experimental and theoretical results. 相似文献
53.
Enantiopure Ti(IV) complexes bearing pseudo-C(3) amino triphenolate ligands have been synthesized and characterized. The complexes bearing ortho phenyl groups act as (1)H NMR chiral solvating agent (CSA) for the stereochemical analysis of a series of sulfoxides. The coordination of a Lewis base coligand (sulfoxide) and the presence of aromatic rings are the key structural factors for the efficiency of the CSA. 相似文献
54.
Dusio GF Cardani D Zanobbio L Mantovani M Luchini P Battini L Galli V Diana A Balsari A Rumio C 《Immunology and cell biology》2011,89(5):630-639
The innate immune system is present throughout the female reproductive tract and functions in synchrony with the adaptive immune system to provide protection in a way that enhances the chances for fetal survival, while protecting against potential pathogens. Recent data show that activation of Toll-like receptor (TLR)2 and 4 by low-molecular weight hyaluronic acid (LMW-HA) in the epidermis induces secretion of the antimicrobial peptide β-defensin 2. In the present work, we show that LMW-HA induces vaginal epithelial cells to release different antimicrobial peptides, via activation of TLR2 and TLR4. Further, we found that LMW-HA favors repair of vaginal epithelial injury, involving TLR2 and TLR4, and independently from its classical receptor CD44. This wound-healing activity of LMW-HA is dependent from an Akt/phosphatidylinositol 3 kinase pathway. Therefore, these findings suggest that the vaginal epithelium is more than a simple physical barrier to protect against invading pathogens: on the contrary, this surface acts as efficient player of innate host defense, which may modulate its antimicrobial properties and injury restitution activity, following LMW-HA stimulation; this activity may furnish an additional protective activity to this body compartment, highly and constantly exposed to microbiota, ameliorating the self-defense of the vaginal epithelium in both basal and pathological conditions. 相似文献
55.
Cavallari N Frigato E Vallone D Fröhlich N Lopez-Olmeda JF Foà A Berti R Sánchez-Vázquez FJ Bertolucci C Foulkes NS 《PLoS biology》2011,9(9):e1001142
The circadian clock is synchronized with the day-night cycle primarily by light. Fish represent fascinating models for deciphering the light input pathway to the vertebrate clock since fish cell clocks are regulated by direct light exposure. Here we have performed a comparative, functional analysis of the circadian clock involving the zebrafish that is normally exposed to the day-night cycle and a cavefish species that has evolved in perpetual darkness. Our results reveal that the cavefish retains a food-entrainable clock that oscillates with an infradian period. Importantly, however, this clock is not regulated by light. This comparative study pinpoints the two extra-retinal photoreceptors Melanopsin (Opn4m2) and TMT-opsin as essential upstream elements of the peripheral clock light input pathway. 相似文献
56.
Gomes CC Moreira LM Santos VJ Ramos AS Lyon JP Soares CP Santos FV 《Genetics and molecular biology》2011,34(1):116-121
The use of artificial implants provides a palliative or permanent solution for individuals who have lost some bodily function through disease, an accident or natural wear. This functional loss can be compensated for by the use of medical devices produced from special biomaterials. Titanium alloy (Ti-6Al-4V) is a well-established primary metallic biomaterial for orthopedic implants, but the toxicity of the chemical components of this alloy has become an issue of concern. In this work, we used the MTT assay and micronucleus assay to examine the cytotoxicity and genotoxicity, respectively, of an extract obtained from this alloy. The MTT assay indicated that the mitochondrial activity and cell viability of CHO-K1 cells were unaffected by exposure to the extract. However, the micronucleus assay revealed DNA damage and an increase in micronucleus frequency at all of the concentrations tested. These results show that ions released from Ti-6Al-4V alloy can cause DNA and nuclear damage and reinforce the importance of assessing the safety of metallic medical devices constructed from biomaterials. 相似文献
57.
58.
Coppola L Comitini F Casucci C Milanovic V Monaci E Marinozzi M Taccari M Ciani M Vischetti C 《New biotechnology》2011,29(1):99-106
Biological systems are being developed all over EU countries to protect water-bodies from pesticide contamination at farm level. A laboratory experiment was carried out to test the efficiency of a mixture of compost and straw in bio-degrading different mixtures of fungicides usually applied in vineyards. At the same time the effects of fungicide applications on microbial community of biomixture were also evaluated. Results showed that the biomixture had a good capability of degrading pesticides. Indeed, at the end of the experiment (112 days), the concentration of most of the pesticides was close to complete degradation. Denaturing gradient gel electrophoresis (DGGE) analysis showed an evident modification of microbial diversity after the addition of fungicides. However, at the end of degradation process, no significant changes in the composition of microbial community were seen. In this specific substrate used in the biomixture, yeast flora and ascomycete filamentous fungi seemed to be involved in the degradation activity. 相似文献
59.
Cristiano Bocci 《Theoretical biology forum》2006,99(3):445-466
In this expository work we describe the main aspects of the so-called Phylogenetic Algebraic Geometry which concerns with the study of algebraic varieties representing statistical models of evolution. In particular, we mainly describe how this field of research can be used to infer phylogenies. 相似文献
60.
Luciano?da Rocha?Corrêa Daniel?Cristiano?Paim Joséli?Schwambach Arthur?Germano?Fett-NetoEmail author 《Plant Growth Regulation》2005,45(1):63-73
Comparisons between related species with different rooting capacities can provide insights into the mechanisms controlling adventitious root development. The availability of carbohydrates is often considered exclusively as an energetic requirement to drive root development; the major regulatory role in the process is often attributed to phytohormones, particularly auxin. The roles of light quantity (irradiance) and carbohydrate supply available to young aseptic donor-plants on the adventitious rooting response of Eucalyptus globulus (rooting recalcitrant) and Eucalyptus saligna (easy-to-root) were examined. The effects of the type of carbohydrate supply (sucrose or glucose) on the rooting response of cuttings was also evaluated. Light intensity supplied to mother-plants (30 or 60 mol m–2 s–1) had limited influence on the rooting response of both species, whereas dark periods were detrimental, particularly for E. globulus. In E. globulus, rooting was promoted by the absence of sucrose in donor-plant media. Presence of sucrose in donor plant medium promoted root number but did not affect rooting percentage of E. saligna. A positive effect of glucose on cutting rhizogenesis was found if this hexose was supplied during the root induction phase, followed by sucrose in the root formation step, especially for E. globulus. The same effect was not seen with fructose. The beneficial effect of glucose in the induction phase on root number was also evident under suboptimal auxin concentrations. 相似文献