10 research outputs found
Cone-beam computed tomography, a new low-dose three-dimensional imaging technique for assessment of bone erosions in rheumatoid arthritis : reliability assessment and comparison with conventional radiography – a BARFOT study
Objectives: To determine the intra- and inter-observer agreement of erosions detected and scored with cone-beam computed tomography (CBCT) of bones in the hands and feet, and to compare CBCT with conventional radiography (CR) for assessment of bone erosions in patients with long-standing rheumatoid arthritis (RA). Method: Thirty patients with long-standing RA from the Better Anti-Rheumatic PharmacOTherapy (BARFOT) cohort were examined with CBCT and CR of hands and feet at their 15 year follow-up. Intra- and inter-class correlation coefficients (ICCs) were calculated. Erosions were analysed with the total rheumatoid arthritis magnetic resonance imaging erosion score (RAMRIS erosion score) for ICCs with CBCT, and with the modified RAMRIS erosion score (RAMRIS-mod.) for the same locations as used in the Sharp van der Heijde score and Sharp van der Heijde erosion score for CR. Results: All 30 patients showed erosions on CBCT and 26 on CR. The ICCs for both intra- and inter-observer reliability were 0.92–0.99. CBCT showed numerically more erosions than CR for all regions compared, although a statistically significant difference was found only for the metacarpophalangeal joints [median number of eroded joints 1.0 (range 0–14) with CBCT and 0.5 (0–13) with CR, p = 0.044]. Conclusion: CBCT has high reproducibility and is more sensitive than CR in detecting erosions in this cohort of patients with long-standing RA. CBCT has the potential to become an important tool in the detection and follow-up of erosions in patients with RA
Persistently active disease is common in patients with rheumatoid arthritis, particularly in women : a long-term inception cohort study
Objectives: Despite improved treatment strategies for rheumatoid arthritis (RA), some patients do not respond satisfactorily. The aim of this study was to investigate the course and outcome of early RA diagnosed during the 1990s and followed for 8 years with a focus on those who did not respond well to treatment. Method: This study included 640 patients (66% women) who were enrolled in the BARFOT (Better Anti-Rheumatic PharmacOTherapy) RA inception cohort between the years 1993 and 1999. The 28-joint count Disease Activity Score (DAS28
Peptide Synthesis Using Proteases as Catalyst
Proteolytic enzymes (proteases) comprise a group of hydrolases (EC 3.4, NC-IUBMB) which share the common feature of acting on peptide bonds. Proteases are among the best studied enzymes in terms of structure-function relationship (Krowarsch et al., 2005). Proteases, by catalyzing the cleavage of other proteins and even themselves, have an enormous physiological significance, their coding genes representing as much as 2% of the total human genome (Schilling and Overall, 2008).Proteases, together with lipases, represent the most important family of enzymes at industrial level, accounting for well over 50% of the enzyme market (Feijoo-Siota and Villa, 2011). Proteases have been used industrially since the onset of enzyme technology in the first decades of the 20th century; many of the early patents issued for the use of enzymes with commercial purposes were proteases, mostly from plant (papain, bromelain) and animal (trypsin, pepsin) origin. Intended uses were in brewing and in leather and rubber manufacturing (Neidelman, 1991). In the decades that follow many large-scale industrial processes were developed using now mostly microbial proteases. A common feature of them was the degradation of proteins and most relevant areas of applications were the food and beverage (Sumantha et al., 2006), detergent (Maurer 2004), leather (Foroughi et al., 2006) and pharmaceutical sectors (Monteiro de Souza et al., 2015). Acid and neutral proteases are relevant to the food industry for the production of protein hydrolyzates (Nielsen and Olsen, 2002), beer chill-proofing (Monsan et al., 1978), meat tenderization (Ashie et al., 2002) and above all, for cheese production (Kim et al., 2004). Alkaline proteases are of paramount importance for the detergent industry (Sellami-Kamoun et al., 2008) and also in tannery (Varela et al., 1997; Thanikaivelan, 2004) and fish-meal production (Schaffeld et al., 1989; Chalamaiah et al., 2012). These conventional applications are by no means outside of continuous technological development (Monteiro de Souza et al. 2015). This is illustrated by the optimization of detergent enzyme performance under the harsh conditions of laundry at high and low temperatures, which has been a continuous challenge tackled by the construction of subtilisin (alkaline protease) variants by random and site-directed mutagenesis and by directed evolution (Kirk et al., 2002; Jares Contesini et al., 2017). It is also illustrated by the production of chymosin in microbial hosts by recombinant DNA technology and further improvement by protein engineering (Mohanty et al., 1999). Therapeutic application of proteases acting as protein hydrolases goes from conventional digestive-aids and anti-inflammatory agents to more sophisticated uses as trombolytic drugs (i.e. urokinase and tissue plasminogen activator) and more recently for the treatment of haemophilia. A comprehensive review on the therapeutic uses of proteases is suggested for the interested reader (Craik et al., 2011)The potential of hydrolytic enzymes for catalyzing reverse reactions of bond formation has been known for quite some time. However, its technological potential as catalysts for organic synthesis developed in the 1980s (Bornscheuer and Kazlauskas, 1999) paralleling the outburst of biocatalysis in non-conventional (non-aqueous) media (Illanes, 2016).Proteases can not only catalyze the cleavage of peptide bonds but, in a proper reaction medium, they can also catalyze the reaction of peptide bond formation. Proteases are highly stereo- and regiospecific, active under mild reaction conditions, do not require coenzymes and are readily available as commodity enzymes, these properties making them quite attractive catalysts for organic synthesis (Bordusa, 2002; Kumar and Bhalla, 2005). Such reactions will not proceed efficiently in aqueous medium where the hydrolytic potential of the enzyme will prevail, so reaction media at low, and hopefully controlled, water activity is necessary for peptide synthesis. This is a major threat since proteases, different from lipases, are not structurally conditioned to act in such environments. The use of proteases in peptide synthesis is analyzed in depth in section 3.4.Fil: Barberis, Sonia Esther. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Luis. Instituto de FĂsica Aplicada "Dr. Jorge AndrĂ©s Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Adaro, Mauricio Omar. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Luis. Instituto de FĂsica Aplicada "Dr. Jorge AndrĂ©s Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Origone, Anabella LucĂa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Luis. Instituto de FĂsica Aplicada "Dr. Jorge AndrĂ©s Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Bersi, Grisel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Luis. Instituto de FĂsica Aplicada "Dr. Jorge AndrĂ©s Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Guzman, Fanny. Pontificia Universidad Catolica de Valparaiso. Escuela de IngenierĂa BioquĂmica; ChileFil: Illanes, Andres. Pontificia Universidad Catolica de Valparaiso. Escuela de IngenierĂa BioquĂmica; Chil