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Follicular occlusion triad: an isotopic response or adverse effect of rituximab?
Follicular occlusion triad is a symptom complex of three conditions with a similar pathophysiology including hidradenitis suppurativa (HS), dissecting cellulitis of the scalp, and acne conglobata. Although the exact pathogenesis of the triad is unknown, it appears to be related to follicular occlusion in areas with apocrine glands. Wolf isotopic response refers to the occurrence of a new dermatosis at the site of another, unrelated, previously healed dermatosis. We present a 26-year-old man with a history of pemphigus foliaceus (PF) who developed large draining nodules with scarring and sinus tracts, compatible with follicular occlusion triad, preferentially at areas previously affected by PF thirteen months after treatment with rituximab. To the authors' knowledge there are no reported cases of follicular occlusion triad or HS manifesting as an isotopic response. However, one member of the triad, HS, has been reported to occur infrequently following the use of biologic agents such as adalimumab, infliximab, tocilizumab, and rituximab for chronic immune-mediated inflammatory diseases (psoriasis, Crohn disease, rheumatoid arthritis, and ankylosing spondylitis)
Semi-rational engineering of cellobiose dehydrogenase for improved hydrogen peroxide production
Abstract Background The ability of fungal cellobiose dehydrogenase (CDH) to generate H2O2 in-situ is highly interesting for biotechnological applications like cotton bleaching, laundry detergents or antimicrobial functionalization of medical devices. CDHâs ability to directly use polysaccharide derived mono- and oligosaccharides as substrates is a considerable advantage compared to other oxidases such as glucose oxidase which are limited to monosaccharides. However CDHâs low activity with oxygen as electron acceptor hampers its industrial use for H2O2 production. A CDH variant with increased oxygen reactivity is therefore of high importance for biotechnological application. Uniform expression levels and an easy to use screening assay is a necessity to facilitate screening for CDH variants with increased oxygen turnover. Results A uniform production and secretion of active Myriococcum thermophilum CDH was obtained by using Saccharomyces cerevisiae as expression host. It was found that the native secretory leader sequence of the cdh gene gives a 3 times higher expression than the prepro leader of the yeast α-mating factor. The homogeneity of the expression in 96-well deep-well plates was good (variation coefficient <15%). A high-throughput screening assay was developed to explore saturation mutagenesis libraries of cdh for improved H2O2 production. A 4.5-fold increase for variant N700S over the parent enzyme was found. For production, N700S was expressed in P. pastoris and purified to homogeneity. Characterization revealed that not only the kcat for oxygen turnover was increased in N700S (4.5-fold), but also substrate turnover. A 3-fold increase of the kcat for cellobiose with alternative electron acceptors indicates that mutation N700S influences the oxidative- and reductive FAD half-reaction. Conclusions Site-directed mutagenesis and directed evolution of CDH is simplified by the use of S. cerevisiae instead of the high-yield-host P. pastoris due to easier handling and higher transformation efficiencies with autonomous plasmids. Twelve clones which exhibited an increased H2O2 production in the subsequent screening were all found to carry the same amino acid exchange in the cdh gene (N700S). The sensitive location of the five targeted amino acid positions in the active site of CDH explains the high rate of variants with decreased or entirely abolished activity. The discovery of only one beneficial exchange indicates that a dehydrogenaseâs oxygen turnover is a complex phenomenon and the increase therefore not an easy target for protein engineering.The authors thank the European Commission (FP7 243529-2-COTTONBLEACH) for financial support. CKP thanks the Austrian Science Fund (FWF) for financial support (grant P22094). IK is a member of the doctoral program BioToP (Biomolecular Technology of Proteins) of the Austrian Science Fund (FWF; W1224). MA thanks the Spanish Government for financial support (BIO2010-19697).Peer Reviewe
NOVI MAGISTERIJI (R. MargaretiÄ UrliÄ) I DOKTORATI (I. MatejÄiÄ, R. BuĆŸanÄiÄ)
Renata MargaretiÄ UrliÄ:
TOTALDIZAJN RADNIÄKOG SVEUÄILIĆ TA âMOĆ A PIJADEâ. PRIMJER KONTINUITETA MODERNE I âSOCIJALISTIÄKO PROSVJETITELJSTVOâ U HRVATSKOJ ARHITEKTURI
Datum obrane magistarskog rada: 8. svibnja 2008.
Ivan MatejÄiÄ:
GRAÄEVNI RAZVOJ KATEDRALE U POREÄU
Datum obrane disertacije: 7. prosinca 2007.
Radoslav BuĆŸanÄiÄ:NIKOLA IVANOV FIRENTINAC, ARHITEKT RENESANSNE OBNOVE TROGIRA KRAJEM 15. STOLJEÄA
Datum obrane disertacije: 29. veljaÄe 2008
A 'Performative' Social Movement: The Emergence of Collective Contentions within Collaborative Governance
The enmeshment of urban movements in networks of collaborative governance has been characterised as a process of co-option in which previously disruptive contentions are absorbed by regimes and reproduced in ways that do not threaten the stability of power relations. Applying a theoretical framework drawn from feminist philosopher Judith Butler this paper directs attention to the development of collective oppositional identities that remain embedded in conventional political processes. In a case study of the English tenants' movement, it investigates the potential of regulatory discourses that draw on market theories of performative voice to offer the collectivising narratives and belief in change that can generate the emotional identification of a social movement. The paper originates the concept of the âperformative social movementâ to denote the contentious claims that continue to emerge from urban movements that otherwise appear quiescent
College of American Pathologists\u27 Laboratory Standards for Next-Generation Sequencing Clinical Tests
Context.-The higher throughput and lower per-base cost of next-generation sequencing (NGS) as compared to Sanger sequencing has led to its rapid adoption in clinical testing. The number of laboratories offering NGS-based tests has also grown considerably in the past few years, despite the fact that specific Clinical Laboratory Improvement Amendments of 1988/College of American Pathologists (CAP) laboratory standards had not yet been developed to regulate this technology. Objective.-To develop a checklist for clinical testing using NGS technology that sets standards for the analytic wet bench process and for bioinformatics or \u27\u27 dry bench\u27\u27 analyses. As NGS-based clinical tests are new to diagnostic testing and are of much greater complexity than traditional Sanger sequencing-based tests, there is an urgent need to develop new regulatory standards for laboratories offering these tests. Design.-To develop the necessary regulatory framework for NGS and to facilitate appropriate adoption of this technology for clinical testing, CAP formed a committee in 2011, the NGS Work Group, to deliberate upon the contents to be included in the checklist. Results.-A total of 18 laboratory accreditation checklist requirements for the analytic wet bench process and bioinformatics analysis processes have been included within CAP\u27s molecular pathology checklist (MOL). Conclusions.-This report describes the important issues considered by the CAP committee during the development of the new checklist requirements, which address documentation, validation, quality assurance, confirmatory testing, exception logs, monitoring of upgrades, variant interpretation and reporting, incidental findings, data storage, version traceability, and data transfer confidentiality
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