A large fraction of HLA class I ligands are proteasome-generated spliced peptides

The proteasome generates the epitopes presented on human leukocyte antigen (HLA) class I molecules that elicit CD8+ T cell responses. Reports of proteasome-generated spliced epitopes exist, but they have been regarded as rare events. Here, however, we show that the proteasome-generated spliced peptide pool accounts for one-third of the entire HLA class I immunopeptidome in terms of diversity and one-fourth in terms of abundance. This pool also represents a unique set of antigens, possessing particular and distinguishing features. We validated this observation using a range of complementary experimental and bioinformatics approaches, as well as multiple cell types. The widespread appearance and abundance of proteasome-catalyzed peptide splicing events has implications for immunobiology and autoimmunity theories and may provide a previously untapped source of epitopes for use in vaccines and cancer immunotherapy

Synthesis of 4-aryl-3(5)-(2-hydroxyphenyl)pyrazoles by reaction of isoflavones and their 4-thio analogues with hydrazine derivatives

4-Aryl-3(5)-2-(hydroxyphenyl)pyrazoles have been prepared by the reaction of isoflavones and their 4-thio analogues with hydrazine hydrate and phenylhydrazine in hot pyridine. The reaction mechanism for the formation of these pyrazoles is discussed. All the new compounds have been fully characterized by NMR spectroscopy. In [D6]DMSO, a 1H NMR study allows observation of the presence of both pyrazole annular tautomers, due to the presence of intramolecular hydrogen bonds in each tautomer (OH•••N and NH•••O). Theoretical calculations have been carried out on tautomers and conformers of compounds 20 (3(5)-(2-hydroxy-4-methoxyphenyl)-5(3)-methyl-4-phenylpyrazole) and 21 (3(5)-(2-hydroxy-4-methoxyphenyl)-4-(2-methoxyphenyl)-5(3)-methylpyrazole), including the absolute shieldings (GIAO/B3 LYP/6?311++G) of 21. © CSIRO 2007.Peer Reviewe

Synthesis of pyrazoles by treatment of 3-benzylchromones, 3-benzylflavones and their 4-thio analogues with hydrazine

The synthesis of pyrazoles 13-24 has been accomplished by treatment of 3-benzylchromones 1-5, 3-benzylflavones 6-12 and their 4-thio analogues 25-29 with hydrazine hydrate in hot pyridine. A plausible reaction mechanism for the formation of pyrazoles 13-24 is discussed. A 1H NMR study in [D 6]DMSO allowed the presence of both pyrazole annular tautomers to be observed, due to the presence of intramolecular hydrogen bonds in each tautomer (OH-N and NH-O). GIAO/B3LYP/6-311++G * * calculations were carried out on some model pyrazoles to provide a theoretical basis for the NMR experimental observations. © Wiley-VCH Verlag GmbH & Co. KGaA, 2006.Peer Reviewe

Deeper insights on alchornea cordifolia (Schumach. & Thonn.) müll.arg extracts: Chemical profiles, biological abilities, network analysis and molecular docking

Alchornea cordifolia (Schumach. & Thonn.) Müll. Arg. is a well-known African medicinal plant traditionally used for various healing purposes. In the present study, methanolic, ethyl acetate and infusion extracts of A. cordifolia leaves were studied for their total phenolic and flavonoid contents and screened for their chemical composition. Moreover, the enzyme (acetyl-and butyryl-cholinesterases, α-amylase, α-glucosidase, and tyrosinase) inhibitory and cytotoxicity activities on HepG2: human hepatocellular carcinoma cells, B16 4A5: murine melanoma cells, and S17: murine bone marrow (normal) cells of extracts were evaluated. Finally, components-targets and docking analyzes were conducted with the aim to unravel the putative mechanisms underlying the observed bio-pharmacological effects. Interestingly, the infusion and methanolic extracts showed significantly higher total phenolic and flavonoid contents compared with the ethyl acetate extract (TPC: 120.38–213.12 mg GAE/g and TFC: 9.66–57.18 mg RE/g). Besides, the methanolic extracts followed by the infusion extracts were revealed to contain a higher number of compounds (84 and 74 compounds, respectively), while only 64 compounds were observed for the ethyl acetate extract. Gallic acid, ellagic acid, shikimic acid, rutin, quercetin, myricetin, vitexin, quercitrin, kaempferol, and naringenin were among the compounds that were commonly identified in all the studied extracts. Additionally, the methanolic and infusion extracts displayed higher antioxidant capacity than ethyl acetate extract in all assays performed. In ABTS and DPPH radical scavenging assays, the methanol extract (500.38 mg TE/g for DPPH and 900.64 mg TE/g for ABTS) exhibited the best ability, followed by the water and ethyl acetate extracts. Furthermore, the extracts exhibited differential enzyme inhibitory profiles. In particular, the methanolic and infusion extracts showed better cytotoxic selectivity activity against human hepatocellular carcinoma cells. Overall, this study demonstrated A cordifolia to be a species worthy of further investigations, given its richness in bioactive phytochemicals and wide potentialities for antioxidants and pharmacological agents

Endovascular repair of an innominate artery pseudoaneurysm using the Valiant Mona LSA branched graft device

A 60-year-old woman involved in a motor vehicle collision presented with a traumatic pseudoaneurysm of the innominate artery origin in addition to multiple concomitant injuries. She was classified as a high-risk candidate for open repair. An experimental thoracic branched graft device was used for coverage of the injury with the addition of a right carotid-to-left carotid-to-left subclavian artery bypass. Follow-up imaging showed resolution of the pseudoaneurysm and patency of her bypass grafts. This is the first described use of the Mona LSA Branch Thoracic Stent Graft System (Medtronic, Minneapolis, Minn) in the innominate artery

Arginine (Di)methylated Human Leukocyte Antigen Class I Peptides Are Favorably Presented by HLA-B*07

Alterations in protein post-translational modification (PTM) are recognized hallmarks of diseases. These modifications potentially provide a unique source of disease-related human leukocyte antigen (HLA) class I-presented peptides that can elicit specific immune responses. While phosphorylated HLA peptides have already received attention, arginine methylated HLA class I peptide presentation has not been characterized in detail. In a human B-cell line we detected 149 HLA class I peptides harboring mono- and/or dimethylated arginine residues by mass spectrometry. A striking preference was observed in the presentation of arginine (di)methylated peptides for HLA-B*07 molecules, likely because the binding motifs of this allele resemble consensus sequences recognized by arginine methyl-transferases. Moreover, HLA-B*07-bound peptides preferentially harbored dimethylated groups at the P3 position, thus consecutively to the proline anchor residue. Such a proline-arginine sequence has been associated with the arginine methyl-transferases CARM1 and PRMT5. Making use of the specific neutral losses in fragmentation spectra, we found most of the peptides to be asymmetrically dimethylated, most likely by CARM1. These data expand our knowledge of the processing and presentation of arginine (di)methylated HLA class I peptides and demonstrate that these types of modified peptides can be presented for recognition by T-cells. HLA class I peptides with mono- and dimethylated arginine residues may therefore offer a novel target for immunotherapy

Arginine (Di)methylated Human Leukocyte Antigen Class I Peptides Are Favorably Presented by HLA-B*07.

Alterations in protein post-translational modification (PTM) are recognized hallmarks of diseases. These modifications potentially provide a unique source of disease-related human leukocyte antigen (HLA) class I-presented peptides that can elicit specific immune responses. While phosphorylated HLA peptides have already received attention, arginine methylated HLA class I peptide presentation has not been characterized in detail. In a human B-cell line we detected 149 HLA class I peptides harboring mono- and/or dimethylated arginine residues by mass spectrometry. A striking preference was observed in the presentation of arginine (di)methylated peptides for HLA-B*07 molecules, likely because the binding motifs of this allele resemble consensus sequences recognized by arginine methyl-transferases. Moreover, HLA-B*07-bound peptides preferentially harbored dimethylated groups at the P3 position, thus consecutively to the proline anchor residue. Such a proline-arginine sequence has been associated with the arginine methyl-transferases CARM1 and PRMT5. Making use of the specific neutral losses in fragmentation spectra, we found most of the peptides to be asymmetrically dimethylated, most likely by CARM1. These data expand our knowledge of the processing and presentation of arginine (di)methylated HLA class I peptides and demonstrate that these types of modified peptides can be presented for recognition by T-cells. HLA class I peptides with mono- and dimethylated arginine residues may therefore offer a novel target for immunotherapy

Overview of the JET results

Since the installation of an ITER-like wall, the JET programme has focused on the consolidation of ITER design choices and the preparation for ITER operation, with a specific emphasis given to the bulk tungsten melt experiment, which has been crucial for the final decision on the material choice for the day-one tungsten divertor in ITER. Integrated scenarios have been progressed with the re-establishment of long-pulse, high-confinement H-modes by optimizing the magnetic configuration and the use of ICRH to avoid tungsten impurity accumulation. Stationary discharges with detached divertor conditions and small edge localized modes have been demonstrated by nitrogen seeding. The differences in confinement and pedestal behaviour before and after the ITER-like wall installation have been better characterized towards the development of high fusion yield scenarios in DT. Post-mortem analyses of the plasma-facing components have confirmed the previously reported low fuel retention obtained by gas balance and shown that the pattern of deposition within the divertor has changed significantly with respect to the JET carbon wall campaigns due to the absence of thermally activated chemical erosion of beryllium in contrast to carbon. Transport to remote areas is almost absent and two orders of magnitude less material is found in the divertor