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131.
Electrospray ionization mass spectrometry (ESI-MS) was used to analyze the hydrogen/deuterium exchange properties of the mastoparan peptide Apoica-MP during interactions with lipid vesicle membranes. Synthetic peptide was incorporated into large unilamellar vesicles (LUVs) of L-alpha-phosphatidylcholine (PC), resulting in proteoliposomes which were then diluted with D2O. After quenching deuteration by the addition of formic acid the H/D exchange was directly analyzed by ESI-MS. This strategy was used to investigate the architecture of the peptide in the membranes of PC LUVs. The deuterated peptide ions were analyzed under collision-induced dissociation (CID) mass spectrometry, which permitted the location of deuterons at the amide sites along the peptide backbone. Intramolecular hydrogen scrambling was investigated both in the free peptide and in its proteoliposome form. Some scrambling was observed for the free peptide; however, almost no scrambling occurred in the amide hydrogens of the peptide backbone embedded in the membrane. The CID spectra suggest that the N-terminal moiety of the peptide lies on the polar side of the lipid membrane, while the C-terminal region is embedded in the membrane. The protocol described here may be reliably applied to investigate the interaction of mastoparans with bilayer lipid systems. 相似文献
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A. Castagna C. Nali S. Ciompi G. Lorenzini G. F. Soldatini A. Ranieri 《The New phytologist》2001,152(2):223-229
134.
N.J. Ribeiro O.C. Pires M. Mota E.C. Ferreira M.M. Alves 《Biotechnology letters》2001,23(22):1833-1839
An upflow velocity of 0.21 m h–1 was optimal to minimize the effect of organic shocks (from 6 to 30 kg COD m–3 d–1) when operating an upflow anaerobic filter for the treatment of an oleic acid-based effluent (50% w/v COD). This value represented the transition between a mass transfer controlled regime and a kinetic regime. Under hydraulic shock loads, an increase in upflow velocity from 0.3 to 0.4m h–1 decreased the removal efficiency from 68 to 51%. 相似文献
135.
The aim of the present study is to clarify the taxonomic position of Teucrium euganeum Vis. vis à vis T.siculum (Rafin.) Guss. and T.scorodonia L. The study is based on an analysis of macro- and micro-morphological characters, type, and distribution of trichomes in different parts of the plant, chromosome counts, and a statistical analysis of such morphometric data. The results of the study allow one to consider the populations of the Euganean Hills (Padua, north-eastern Italy) as a sub-species of T.siculum, and, therefore, a new combination is proposed: Teucrium siculum (Rafin.) Guss. subsp. euganeum (Vis.) Tornadore, comb. et stat.nov. 相似文献
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Bibiana S. O. Fam Guillermo Reales Pedro Vargas‐Pinilla Pamela Par Lucas H. Viscardi Vinicius A. Sortica Aline B. Felkl lvaro de O. Franco Aldo B. Lucion Claudio M. Costa‐Neto Alcides Pissinatti Francisco M. Salzano Vanessa R. Paixo‐Crtes Maria Ctira Bortolini 《American journal of primatology》2019,81(8)
Platyrrhini (New World monkeys, NWm) are a group of primates characterized by behavioral and reproductive traits that are otherwise uncommon among primates, including social monogamy, direct paternal care, and twin births. As a consequence, the study of Platyrrhine primates is an invaluable tool for the discovery of the genetic repertoire underlying these taxon‐specific traits. Recently, high conservation of vasopressin (AVP) sequence, in contrast with high variability of oxytocin (OXT), has been described in NWm. AVP and OXT functions are possible due to interaction with their receptors: AVPR1a, AVPR1b, AVPR2, and OXTR; and the variability in this system is associated with the traits mentioned above. Understanding the variability in the receptors is thus fundamental to understand the function and evolution of the system as a whole. Here we describe the variability of AVPR1b coding region in 20 NWm species, which is well‐known to influence behavioral traits such as aggression, anxiety, and stress control in placental mammals. Our results indicate that 4% of AVPR1b sites may be under positive selection and a significant number of sites under relaxed selective constraint. Considering the known role of AVPR1b, we suggest that some of the changes described here for the Platyrrhini may be a part of the genetic repertoire connected with the complex network of neuroendocrine mechanisms of AVP–OXT system in the modulation of the HPA axis. Thus, these changes may have promoted the emergence of social behaviors such as direct paternal care in socially monogamous species that are also characterized by small body size and twin births. 相似文献
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Simone C. Wuest Ina Mexhitaj Noo Ri Chai Elena Romm Joerg Scheffel Biying Xu Kelly Lane Tianxia Wu Bibiana Bielekova 《PloS one》2014,9(8)
Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system (CNS). Neither the antigenic target(s) nor the cell population(s) responsible for CNS tissue destruction in MS have been fully defined. The objective of this study was to simultaneously determine the antigen (Ag)-specificity and phenotype of un-manipulated intrathecal CD4+ and CD8+ T cells of patients with relapsing-remitting and progressive MS compared to subjects with other inflammatory neurological diseases. We applied a novel Ag-recognition assay based on co-cultures of freshly obtained cerebrospinal fluid T cells and autologous dendritic cells pre-loaded with complex candidate Ag''s. We observed comparably low T cell responses to complex auto-Ag''s including human myelin, brain homogenate, and cell lysates of apoptotically modified oligodendroglial and neuronal cells in all cohorts and both compartments. Conversely, we detected a strong intrathecal enrichment of Epstein-Barr virus- and human herpes virus 6-specific (but not cytomegalovirus-specific) reactivities of the Th1-phenotype throughout all patients. Qualitatively, the intrathecal enrichment of herpes virus reactivities was more pronounced in MS patients. This enrichment was completely reversed by long-term treatment with the IL-2 modulating antibody daclizumab, which strongly inhibits MS disease activity. Finally, we observed a striking discrepancy between diminished intrathecal T cell proliferation and enhanced cytokine production of herpes virus-specific T cells among progressive MS patients, consistent with the phenotype of terminally differentiated cells. The data suggest that intrathecal administration of novel therapeutic agents targeting immune cells outside of the proliferation cycle may be necessary to effectively eliminate intrathecal inflammation in progressive MS. 相似文献