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IntroductionDisease activity and therapy show an impact on cellular and serological parameters in patients with systemic lupus erythematosus (SLE). This study was performed to compare the influence of mycophenolate mofetil (MMF) and cyclophosphamide (CYC) therapy on these parameters in patients with flaring, organ-threatening disease.MethodsSLE patients currently receiving CYC (n = 20), MMF (n = 25) or no immunosuppressive drugs (n = 22) were compared using a cross-sectional design. Median disease activity and daily corticosteroid dose were similar in these treatment groups. Concurrent medication, organ manifestations, and disease activity were recorded, and cellular and serological parameters were determined by routine diagnostic tests or flow cytometric analysis. In addition follow-up data were obtained from different sets of patients (CYC n = 24; MMF n = 23).ResultsAlthough both drugs showed a significant effect on disease activity and circulating B cell subsets, only MMF reduced circulating plasmablasts and plasma cells as well as circulating free light chains within three months of induction therapy. Neither MMF nor CYC were able to reduce circulating memory B cells. MMF lowered IgA levels more markedly than CYC. We did not observe a significant difference in the reduction of IgG levels or anti-dsDNA antibodies comparing patients receiving MMF or CYC. In contrast to MMF, induction therapy with CYC was associated with a significant increase of circulating CD8+ effector T cells and plasmacytoid dendritic cells (PDCs) after three months.ConclusionsThe results indicate differences between MMF and CYC with regard to the mechanism of action. MMF, but not CYC, treatment leads to a fast and enduring reduction of surrogate markers of B cell activation, such as circulating plasmablasts, plasma cells and free light chains but a comparable rate of hypogammaglobulinemia.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0603-8) contains supplementary material, which is available to authorized users.  相似文献   
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BACKGROUND: Corals worldwide are in decline due to climate change effects (e.g., rising seawater temperatures), pollution, and exploitation. The ability of corals to cope with these stressors in the long run depends on the evolvability of the underlying genetic networks and proteins, which remain largely unknown. A genome-wide scan for positively selected genes between related coral species can help to narrow down the search space considerably. METHODOLOGY/PRINCIPAL FINDINGS: We screened a set of 2,604 putative orthologs from EST-based sequence datasets of the coral species Acropora millepora and Acropora palmata to determine the fraction and identity of proteins that may experience adaptive evolution. 7% of the orthologs show elevated rates of evolution. Taxonomically-restricted (i.e. lineage-specific) genes show a positive selection signature more frequently than genes that are found across many animal phyla. The class of proteins that displayed elevated evolutionary rates was significantly enriched for proteins involved in immunity and defense, reproduction, and sensory perception. We also found elevated rates of evolution in several other functional groups such as management of membrane vesicles, transmembrane transport of ions and organic molecules, cell adhesion, and oxidative stress response. Proteins in these processes might be related to the endosymbiotic relationship corals maintain with dinoflagellates in the genus Symbiodinium. CONCLUSION/RELEVANCE: This study provides a birds-eye view of the processes potentially underlying coral adaptation, which will serve as a foundation for future work to elucidate the rates, patterns, and mechanisms of corals' evolutionary response to global climate change.  相似文献   
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Enzymatic synthesis and purification of aromatic coenzyme a esters   总被引:1,自引:0,他引:1  
Two recombinant His-tagged proteins, a plant 4-coumarate:coenzyme A ligase (EC 6.2.1.12) and a bacterial benzoate:coenzyme A ligase (EC 6.2.1.25), were expressed in Escherichia coli and purified in a single step using Ni-chelating chromatography. Purified enzymes were used to synthesize cinnamoyl-coenzyme A (CoA), p-coumaroyl-CoA, feruloyl-CoA, caffeoyl-CoA, and benzoyl-CoA. Conversions up to 95% were achieved. Using a rapid solid-phase extraction procedure, the target CoA esters were isolated with yields of up to 80%. Structures were confirmed by analytical comparison with chemically synthesized reference compounds and electrospray ionization-mass spectrometry. The recombinant enzymes were stable for several months at -80 degrees C, thus providing a reliable and facile method to produce these delicate biological intermediates.  相似文献   
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Polyketides are a structurally and functionally diverse family of bioactive natural products that are used extensively as pharmaceuticals and agrochemicals. In bacteria these molecules are biosynthesized by giant, multi-functional enzymatic complexes, termed modular polyketide synthases (PKSs), that function in assembly-line like fashion to fuse and tailor simple carboxylic acid monomers into a vast array of elaborate chemical scaffolds. Modifying PKSs through targeted synthase re-engineering is a promising approach for accessing functionally-optimized polyketides. Due to their highly mosaic architectures the recently identified trans-AT family of modular synthases appear inherently more amenable to re-engineering than their well studied cis-AT counterparts. Here, we review recent progress in the re-engineering of trans-AT PKSs, summarize opportunities for harnessing the biosynthetic potential of these systems, and highlight challenges that such re-engineering approaches present.  相似文献   
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We report on results from an Internet survey of sleeping habits in a Dutch population using the Munich Chronotype Questionnaire (MCTQ), supplemented with the Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ). The MCTQ was completed by 5,055 responders, of which 2,481 also completed the MEQ. MEQ score correlated well with the MCTQ assessment of time of mid-sleep on free days (MSF; r = - 0.73) and on workdays (MSW; r = - 0.61). MEQ was more strongly correlated with MSF (50% of sleep time) than with sleep onset (0%), rise time (100%), or with any other percentile (10 to 40, 60% to 90%) of sleep on free days. The study shows that chronotype (based on MSF as measured by the MCTQ) strongly correlates with morningness-eveningness (as measured by the MEQ). However, the MCTQ collects additional detailed information on sleep-wake behavior under natural conditions.  相似文献   
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PERMOL: restraint-based protein homology modeling using DYANA or CNS   总被引:1,自引:0,他引:1  
SUMMARY: PERMOL is a new restraint-based program for homology modeling of proteins. Restraints are generated from the information contained in structures of homologous template proteins. Employing the restraints generated by PERMOL, three-dimensional structures are obtained using MD programs such as DYANA or CNS. In contrast to other programs PERMOL is mainly based on the use of dihedral angle information which is optimally suited to preserve the local secondary structure. The global arrangement of these elements is then facilitated by a small number of distance restraints. Using PERMOL homology, models of high quality are obtained. A key advantage of the proposed method is its flexibility, which allows the inclusion of data from other sources, such as experimental restraints and the use of modern molecular dynamics programs to calculate structures. AVAILABILITY: The software and a detailed manual are available free of charge (http://www.biologie.uni-regensburg.de/Biophysik/Kalbitzer/permol/permol.html)  相似文献   
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BACKGROUND: Binder syndrome is a maxillonasal dysostosis characterized by midface and nasal hypoplasia, sometimes associated with short terminal phalanges of fingers and toes and transient radiological features of chondrodysplasia punctata. Warfarin- or phenytoin-induced vitamin K deficiency during early pregnancy is a well-established etiology for this syndrome, which occurs nevertheless sporadically in most cases. CASE(S): We describe here the first case, to our knowledge, of Binder syndrome in a child whose mother presented with biliary lithiasis in early pregnancy. The mother proved to have a decrease in clotting factors II, VII, and X, and in prothrombin time, at 11 weeks of gestation, which was highly suggestive of vitamin K deficiency. CONCLUSIONS: The biliary lithiasis-induced vitamin K deficiency in early pregnancy is likely to have resulted in Binder syndrome. This observation should prompt physicians to carefully check for vitamin K deficiency in pregnant women presenting with biliary lithiasis, in order to prevent Binder syndrome in the fetus by providing intravenous vitamin K supplementation as soon as possible. Finally, reassuring genetic counseling regarding the genetic risk for future pregnancies is to be provided to the parents.  相似文献   
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