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Background: The efficacy of tocilizumab (TCZ) in the treatment of Takayasu arteritis (TA) was demonstrated in randomized controlled trials. The objective of this study was to analyse the effectiveness of combining TCZ with glucocorticoids (GC) as induction therapy in patients with TA. Method: This was a retrospective observational study including 32 patients with newly diagnosed TA. [ABSTRACT FROM AUTHOR]

Photoreaction of a mixture of Cp*(CO)3WMe (Cp* = η5-C5Me5) and HSiR2Ar [R2Ar = Me2Ph, Me2(p-Tol), Me(p-Tol)2, and (p-Tol)3] in the presence of 4-(dimethylamino)pyridine (DMAP) gave DMAP-stabilized aryl(silylene) complexes Cp*(CO)2W(Ar)(SiR2·DMAP) [1a, R = Me, Ar = Ph; 1b, R = Me, Ar = p-Tol; 1c, R2= Me(p-Tol), Ar = p-Tol; 1d, R = Ar = p-Tol] via 1,2-migration of the aryl group from a silyl ligand to a tungsten center. Thermal reactions of Cp*(CO)2W(DMAP)Me (2) with HSiR2Ar at room temperature also gave 1a−d, and in all cases the yields were higher than those in the photoreaction. Silylene complexes 1a−deasily isomerized to arylsilyl complexes Cp*(CO)2W(DMAP)(SiR2Ar) [3a, R = Me, Ar = Ph; 3b, R = Me, Ar = p-Tol; 3c, R2= Me(p-Tol), Ar = p-Tol; 3d, R = Ar = p-Tol] at 40−55 °C. On the other hand, irradiation of arylsilyl complexes 3a−dreproduced silylene complexes 1a−d, implying that the 1,2-aryl-migration between tungsten and silicon is reversible. The molecular structures of 1c, 2, 3a, and 3dwere determined by X-ray crystallography. A kinetic study on the 1,2-aryl-migration in the thermal isomerization from 1a−dto 3a−dsuggests that the rate-determining step involves dissociation of DMAP from 1a−d. [ABSTRACT FROM AUTHOR]

Treatment of Cp(CO)2W(NCMe)Me (Cp 5-C5Me5) with HSiR3(R Et, p-Tol) afforded N-silylated 2-iminoacyl tungsten complexes Cp(CO)2W2(C,N)-C(Me)N(SiR3) (1a, R Et; 1b, R p-Tol). Analogous reactions in the presence of excess acetonitrile for a prolonged reaction time led to the formation of five-membered metallacycles Cp(CO)2W2(C,N)-C(Me)N−C(Me)N(H) (2) and Cp(CO)2W2(C,N)-C(CH2SiR3)N−C(Me)N(H) (3, R p-Tol) through a C−N coupling of nitrile molecules and migration of a silyl group. [ABSTRACT FROM AUTHOR]

Objectives: Rituximab (RTX) efficacy for anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) has been reported in large randomized studies; however, the efficacy of RTX in Japanese AAV patients, especially the elderly, is not well known. We aimed to determine the clinical efficacy of RTX in Japanese AAV patients including elderly patients. Methods: This study included 78 AAV patients newly diagnosed with AAV and treated in Fukushima Medical University Hospital or Ohta-Nishinouchi Hospital from April 2004 to September 2019. Clinical records were retrospectively reviewed, and clinical efficacy and outcome (1-year survival) between the RTX treatment group (23 cases) and the conventional therapy group (immunosuppressive therapy other than RTX, 55 cases) were compared. We also analysed the clinical efficacy and outcome in elderly-onset (>75 years) AAV patients. Results: The RTX group showed similar efficacy and 1-year survival compared to the conventional therapy group. Conversely, after 6 months of treatment, prednisolone doses significantly decreased in the RTX group compared to the conventional therapy group (p < 0.01). In the elderlyonset AAV patients, clinical efficacy and outcome were not significantly different. Conclusions: RTX was effective in Japanese AAV patients and may be useful for prompt tapering of prednisolone doses, even in elderly-onset AAV patients. [ABSTRACT FROM AUTHOR]

The friend leukemia insertion site 1 (Fli-1) transcription factor, an Ets family member, is implicated in the pathogenesis of systemic lupus erythematosus in human patients and murine models of lupus. Lupus-prone mice with reduced Fli-1 expression have significantly less nephritis, prolonged survival, and decreased infiltrating inflammatory cells into the kidney. Inflammatory chemokines, including CCL5, are critical for attracting inflammatory cells. In this study, decreased CCL5 mRNA expression was observed in kidneys of lupus-prone NZM2410 mice with reduced Fli-1 expression. CCL5 protein expression was significantly decreased in endothelial cells transfected with Fli-1-specific small interfering RNA compared with controls. Fli-1 binds to endogenous Ets binding sites in the distal region of the CCL5 promoter. Transient transfection assays demonstrate that Fli-1 drives transcription from the CCL5 promoter in a dose-dependent manner. Both Ets1, another Ets family member, and Fli-1 drive transcription from the CCL5 promoter, although Fli-1 transactivation was significantly stronger. Ets1 acts as a dominant-negative transcription factor for Fli-1, indicating that they may have at least one DNA binding site in common. Systematic deletion of DNA binding sites demonstrates the importance of the sites located within a 225-bp region of the promoter. Mutation of the Fli-1 DNA binding domain significantly reduces transactivation of the CCL5 promoter by Fli-1. We identified a novel regulator of transcription for CCL5. These results suggest that Fli-1 is a novel and critical regulator of proinflammatory chemokines and affects the pathogenesis of disease through the regulation of factors that recruit inflammatory cells to sites of inflammation. [ABSTRACT FROM AUTHOR]

Qβ replicase functioning in Escherichia coli is an RNA-dependent RNA polymerase composed of one phage-coded subunit and three host-coded proteins: ribosomal protein S1, and protein elongation factors EF-Tu and EF-Ts. Qβ replicase lacking ribosomal protein S1 (α-less replicase) is capable of replicating some small RNAs. We attempted to create functional α-less replicase by co-expression of the mRNAs that code for the subunits of α-less replicase in a rabbit reticulocyte cell-free translation system. Replicase activity, however, could not be detected when both EF-Tu and EF-Ts were co-expressed with the phage-coded subunit. On the other hand, active α-less replicase was obtained when an EF-Ts-EF-Tu fusion protein was co-expressed with the phage-coded subunit. Consequently, we succeeded in generating genetically engineered active α-less Qβ replicase which functions in a eukaryotic cell-free system. [ABSTRACT FROM AUTHOR]

Objective: HLA class II alleles are major determinants of genetic predisposition to rheumatic diseases. Predisposing effects of HLA had been suggested in AOSD, however, ethnic differences may account for variations in AOSD association with HLA. We determined the contribution of HLA-DQB1, DPB1 alleles to susceptibility to Adult-onset Still's disease (AOSD) in the Japanese population. Methods: HLA-DQB1 and DPB1 alleles were analyzed in 87 Japanese patients with AOSD and 413 Japanese healthy subjects. Results: We found significant association between HLA-DQB1*06:02 (Pc¼0.010, odds ratio: 2.54) and AOSD, whereas there was no association between the DQB1*06:02 allele and disease phenotypes of AOSD. Moreover, we did not find a predisposing effect of the HLA-DPB1 allele to AOSD. Haplotype analysis showed that presence of DRB1*15:01-DQB1*06:02 was associated with Japanese patients with AOSD. However, conditional logistic regression tests were unable to demonstrate independent association between DRB1*1501 or DQB1*0602 and AOSD. Conclusions: Our results show significant association between AOSD and the HLA DQB1*06:02 allele, and between the DRB1*1501-DQB1*06:02 haplotype and AOSD susceptibility. These findings suggest that genetic susceptibility to AOSD depends on the genotype combinations of HLA DRB1 and DQB1 alleles. [ABSTRACT FROM AUTHOR]

Objective: Monosodium urate (MSU) has been shown to promote interleukin-1b (IL-1b) secretion in human monocytes, but the priming signals for NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway remains elusive. In this study, we investigated the role of Tumor necrosis factor-alpha (TNF-a) on MSU-mediated IL-1b induction in human neutrophils. Methods: Human neutrophils were stimulated with MSU, in the presence or absence of TNF-a priming. The cellular supernatants were analyzed for IL-1b, IL-18, and caspase-1 by enzyme-linked immunosorbent assay (ELISA) methods. Pro-IL-1β mRNA expressions in human neutrophils were analyzed by real-time PCR method. Results: TNF-α stimulation induced pro-IL-1β mRNA expression; however, MSU stimulation did not induce pro-IL-1β mRNA expression in human neutrophils. TNF-α alone or MSU stimulation did not result in efficient IL-1β secretion in human neutrophils, whereas in TNF-α-primed neutrophils, MSU stimulation resulted in a marked IL-1β and IL-18 secretion. TNF-α-primed neutrophils secreted cleaved caspase-1 (p20), in response to MSU stimulation. Conclusion: Our data demonstrate that priming of human neutrophils with TNF-α promotes uric acid-mediated IL-1β secretion in the absence of microbial stimulation. These findings provide insights into the neutrophils-mediated inflammatory processes in gouty arthritis. [ABSTRACT FROM AUTHOR]

Branching enzyme (BE) catalyzes the formation of α-1,6-glucosidic linkages in amylopectin and glycogen. The reaction products are variable, depending on the organism sources, and the mechanistic basis for these different outcomes is unclear. Although most cyanobacteria have only one BE isoform belonging to glycoside hydrolase family 13, Cyanothece sp. ATCC 51142 has three isoforms (BE1, BE2, and BE3) with distinct enzymatic properties, suggesting that investigations of these enzymes might provide unique insights into this system. Here, we report the crystal structure of ligand-free wild-type BE1 (residues 5-759 of 1-773) at 1.85 Å resolution. The enzyme consists of four domains, including domain N, carbohydrate-binding module family 48 (CBM48), domain A containing the catalytic site, and domain C. The central domain A displays a (β/α)8-barrel fold, whereas the other domains adopt β-sandwich folds. Domain N was found in a new location at the back of the protein, forming hydrogen bonds and hydrophobic interactions with CBM48 and domain A. Site-directed mutational analysis identified a mutant (W610N) that bound maltoheptaose with sufficient affinity to enable structure determination at 2.30 Å resolution. In this structure, maltoheptaose was bound in the active site cleft, allowing us to assign subsites -7 to -1. Moreover, seven oligosaccharide-binding sites were identified on the protein surface, and we postulated that two of these in domain A served as the entrance and exit of the donor/acceptor glucan chains, respectively. Based on these structures, we propose a substrate binding model explaining the mechanism of glycosylation/deglycosylation reactions catalyzed by BE. [ABSTRACT FROM AUTHOR]

At variance with the starch-accumulating plants and most of the glycogen-accumulating cyanobacteria, Cyanobacterium sp. CLg1 synthesizes both glycogen and starch. We now report the selection of a starchless mutant of this cyanobacterium that retains wild-type amounts of glycogen. Unlike other mutants of this type found in plants and cyanobacteria, this mutant proved to be selectively defective for one of the two types of glycogen/starch synthase: GlgA2. This enzyme is phylogenetically related to the previously reported SSIII/SSIV starch synthase that is thought to be involved in starch granule seeding in plants. This suggests that, in addition to the selective polysaccharide debranching demonstrated to be responsible for starch rather than glycogen synthesis, the nature and properties of the elongation enzyme define a novel determinant of starch versus glycogen accumulation. We show that the phylogenies of GlgA2 and of 16S ribosomal RNA display significant congruence. This suggests that this enzyme evolved together with cyanobacteria when they diversified over 2 billion years ago. However, cyanobacteria can be ruled out as direct progenitors of the SSIII/SSIV ancestral gene found in Archaeplastida. Hence, both cyanobacteria and plants recruited similar enzymes independently to perform analogous tasks, further emphasizing the importance of convergent evolution in the appearance of starch from a preexisting glycogen metabolism network. [ABSTRACT FROM AUTHOR]