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951.
Low molecular weight glutenin subunits (LMW-GS) are typically subdivided into three groups, according to their molecular weights and isoelectric points, namely the B-, C-, and D groups. Enriched B- and C-type LMW-GS fractions extracted from the bread wheat cultivar Chinese Spring were characterized using high performance liquid chromatography (HPLC) directly interfaced with electrospray ionization mass spectrometry and HPLC coupled off-line with matrix-assisted laser desorption/ionization mass spectrometry, in order to ascertain the number and relative molecular masses of the components present in each fraction and determine the number of cysteine residues. About 70 components were detected in each of the fractions examined by the combined use of these two techniques, with 18 components common to both fractions. Analysis of the fractions after alkylation with 4-vinylpyridine allowed determination of the number of the cysteines present in about 40 subunits. The proteins detected were tentatively classified based on the relative molecular masses and number of cysteine residues. Cross-contamination was found in both B- and C- fractions, along with the presence of D-type LMW-GS. The two fractions also contained unexpected components, probably lipid transfer proteins and omega-gliadins. The presence of extensive microheterogeneity was suggested by the detection of several co-eluting proteins with minor differences in their molecular masses. 相似文献
952.
Influence of cell distribution and diabetes status on the association between mitochondrial DNA copy number and aging phenotypes in the InCHIANTI study
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Ann Zenobia Moore Jun Ding Marcus A. Tuke Andrew R. Wood Stefania Bandinelli Timothy M. Frayling Luigi Ferrucci 《Aging cell》2018,17(1)
Mitochondrial DNA copy number (mtDNA‐CN) estimated in whole blood is a novel marker of mitochondrial mass and function that can be used in large population‐based studies. Analyses that attempt to relate mtDNA‐CN to specific aging phenotypes may be confounded by differences in the distribution of blood cell types across samples. Also, low or high mtDNA‐CN may have a different meaning given the presence of diseases associated with mitochondrial damage. We evaluated the impact of blood cell type distribution and diabetes status on the association between mtDNA‐CN and aging phenotypes, namely chronologic age, interleukin‐6, hemoglobin, and all‐cause mortality, among 672 participants of the InCHIANTI study. After accounting for white blood cell count, platelet count, and white blood cell proportions in multivariate models, associations of mtDNA‐CN with age and interleukin‐6 were no longer statistically significant. Evaluation of a statistical interaction by diabetes status suggested heterogeneity of effects in the analysis of mortality (P < 0.01). The magnitude and direction of associations between mtDNA‐CN estimated from blood samples and aging phenotypes are influenced by the sample cell type distribution and disease status. Therefore, accounting for these factors may aid understanding of the relevance of mitochondrial DNA copy number to health and aging. 相似文献
953.
Sara Savelli Luisa Trombi Delfo DAlessandro Stefania Moscato Simone Pacini Stefano Giannotti Simone Lapi Fabrizio Scatena Mario Petrini 《Cytotherapy》2018,20(4):556-563
Background
Bone Marrow MSCs are an appealing source for several cell-based therapies. Many bioreactors, as the Quantum Cell Expansion System, have been developed to generate a large number of MSCs under Good Manufacturing Practice conditions by using Human Platelet Lysate (HPL). Previously we isolated in the human bone marrow a novel cell population, named Mesodermal Progenitor Cells (MPCs), which we identified as precursors of MSCs. MPCs could represent an important cell source for regenerative medicine applications. As HPL gives rise to a homogeneus MSC population, limiting the harvesting of other cell types, in this study we investigated the efficacy of pooled human AB serum (ABS) to provide clinically relevant numbers of both MSCs and MPCs for regenerative medicine applications by using the Quantum System.Methods
Bone marrow aspirates were obtained from healthy adult individuals undergoing routine total hip replacement surgery and used to generate primary cultures in the bioreactor. HPL and ABS were tested as supplements to culture medium. Morphological observations, cytofluorimetric analysis, lactate and glucose level assessment were performed.Results
ABS gave rise to both heterogeneous MSC and MPC population. About 95% of cells cultured in HPL showed a fibroblast-like morphology and typical mesenchymal surface markers, but MPCs were scarcely represented.Discussion
The use of ABS appeared to sustain a large scale MSC production, as well as the recovery of a subset of MPCs, and resulted a suitable alternative to HPL in the cell generation based on the Quantum System. 相似文献954.
Gaetana Paolella Marilena Lepretti Stefania Martucciello Merlin Nanayakkara Salvatore Auricchio Carla Esposito Maria Vittoria Barone Ivana Caputo 《Cell biology international》2018,42(1):112-120
Alpha‐gliadin peptide 31–43 is considered to be the main peptide responsible for the innate immune response in celiac disease patients. Recent evidence indicates that peptide 31–43 rapidly enters cells and interacts with the early endocytic vesicular compartment. However, the mechanism of its uptake is not completely understood. Our aim is to characterize, isolate and identify possible cell surface proteins involved in peptide 31–43 internalization by Caco‐2 cells. In this study, we used a chemical cross‐linker to block peptide 31–43 on cell surface proteins, and pulled‐down peptide‐proteins complexes using antibodies raised against peptide 31–43. Through this experimental approach, we did not observe any specific complex between cell proteins and peptide 31–43 in Coomassie‐stained denaturating gels or by Western blotting. We also found that type 2 transglutaminase was not necessary for peptide 31–43 internalization, even though it had a regulatory role in the process. Finally, we demonstrated that peptide 31–43 did not behave as a classical ligand, indeed the labeled peptide did not displace the unlabeled peptide in a competitive binding assay. On the basis of these findings and of previous evidence demonstrating that peptide 31–43 is able to interact with a membrane‐like environment in vitro, we conclude that membrane composition and organization, rather than a specific receptor protein, may have a major role in peptide 31–43 internalization by cells. 相似文献
955.
Paola Punzo Alessandra Ruggiero Marco Possenti Roberta Nurcato Antonello Costa Giorgio Morelli Stefania Grillo Giorgia Batelli 《The Plant journal : for cell and molecular biology》2018,94(6):991-1009
Modulation of growth in response to environmental cues is a fundamental aspect of plant adaptation to abiotic stresses. TIP41 (TAP42 INTERACTING PROTEIN OF 41 kDa) is the Arabidopsis thaliana orthologue of proteins isolated in mammals and yeast that participate in the Target‐of‐Rapamycin (TOR) pathway, which modifies cell growth in response to nutrient status and environmental conditions. Here, we characterized the function of TIP41 in Arabidopsis. Expression analyses showed that TIP41 is constitutively expressed in vascular tissues, and is induced following long‐term exposure to NaCl, polyethylene glycol and abscisic acid (ABA), suggesting a role of TIP41 in adaptation to abiotic stress. Visualization of a fusion protein with yellow fluorescent protein indicated that TIP41 is localized in the cytoplasm and the nucleus. Abolished expression of TIP41 results in smaller plants with a lower number of rosette leaves and lateral roots, and an increased sensitivity to treatments with chemical TOR inhibitors, indicating that TOR signalling is affected in these mutants. In addition, tip41 mutants are hypersensitive to ABA at germination and seedling stage, whereas over‐expressing plants show higher tolerance. Several TOR‐ and ABA‐responsive genes are differentially expressed in tip41, including iron homeostasis, senescence and ethylene‐associated genes. In yeast and mammals, TIP41 provides a link between the TOR pathway and the protein phosphatase 2A (PP2A), which in plants participates in several ABA‐mediated mechanisms. Here, we showed an interaction of TIP41 with the catalytic subunit of PP2A. Taken together, these results offer important insights into the function of Arabidopsis TIP41 in the modulation of plant growth and ABA responses. 相似文献
956.
Filiberto Belli Flavio Arienti J. Sulé-Suso C. Clemente Luigi Mascheroni Alessandro Cattelan Cristina Santantonio Gian Francesco Gallino Cecilia Melani Stefania Rao Mario P. Colombo Michele Maio Natale Cascinelli G. Parmiani 《Cancer immunology, immunotherapy : CII》1997,44(4):197-203
From January 1994 to July 1996 we immunized metastatic melanoma patients with HLA-A2-compatible, interleukin-2 (IL-2)-secreting,
immunogenic melanoma lines in an attempt to induce a systemic reaction that might also affect distant melanoma lesions. Twelve
patients (6 male and 6 female) aged from 28 to 72 years, affected with visceral and/or subcutaneous (s.c.) melanoma metastases,
were treated. Two different HLA-A2+ melanoma lines were transduced with the human IL-2 gene (14932/IL-2 and 1B6/IL-2) and used as vaccine. Two groups of 4 patients
each were injected s.c. with 5×107 and 15×107 irradiated 14932/IL-2 melanoma cells respectively, whereas a third group received 5×107 cells of the second line (1B6/IL-2). All patients received the vaccine on days 1, 13, 26; if no progression was evident,
further immunizations were administered at monthly intervals. All patients were assessable for clinical response after at
least three injections of the vaccine. In 4 cases a stabilization of disease lasting from 2 to 6 months was observed; in 2
of them a mixed type of response to treatment was noted with simultaneous evidence of regressing and non-responding lesions
in the same patients. No signs of clinical response were found in the remaining patients. Nine patients died of disease between
3 and 24 months after the onset of therapy, whereas 3 were alive 3 months after the end of therapy. The local and systemic
side-effects of treatment were mild. These results indicate that vaccination with cells bearing the appropriate antigens and
releasing IL-2 locally can produce weak clinical responses, but also indicate that better results may be achieved through
modifications of the vaccine, the schedule of immunization and/or a more appropriate selection of patients.
Received: 20 December 1996 / Accepted: 27 February 1997 相似文献
957.
CO2 assimilation, xanthophyll cycle pigments and PSII efficiency in pumpkin plants as affected by ozone fumigation 总被引:2,自引:0,他引:2
Stefania Ciompi Antonella Castagna Annamaria Ranieri Cristina Nali Giacomo Lorenzini Gian Franco Soldatini 《Physiologia plantarum》1997,101(4):881-889
CO2 assimilation, xanthophyll cycle pigments and PSII efficiency were analyzed in two different ages of pumpkin leaves (Cucurbita pepo L. cv. Ambassador) exposed to 150 nmol mol-1 of ozone (5 days, 5 h day-1). Gas-exchange measurements revealed a reduction in CO2 assimilation and stomatal conductance, accompanied by an increase in the intercellular CO2 concentration both in young and in mature leaves as compared to their respective controls. In both leaves, F0 remained unchanged, while Fm and the Fv/Fm ratio decreased after O3 fumigation, indicating that ozone may induce an alteration in the capability of photosystem II (PSII) to reduce the primary acceptor QA. In the mature leaves the photochemical quenching (qp) was significantly lowered by the pollutant, but this was not the case in the young leaves where qp did not change. In both mature and young ozonated pumpkin leaves, the development of non-photochemical quenching caused a decrease in the PSII photochemical rate, as shown by the correlation between Fv/Fm and the de-epoxidation state of dark-adapted leaves. Decreases in the Fv/Fm ratio are generally attributed to damage to the PSII reaction centre, apart from the down-regulation of the capacity of PSII electron transport. While in young ozonated leaves the decrease in the Fv/Fm ratio was not associated with damage to the D1 protein, in mature ozonated pumpkin leaves, the decrease in the Fv/Fm was accompanied by a significant decline in the D1 content. In conclusion, ozone exposure induces alterations in the light reactions of photosynthesis in both young and mature leaves. However, in young leaves the engagement of the xanthophyll cycle appears to counteract ozone effects against the photosynthetic apparatus as demonstrated by the absence of damage to the D1 protein. On the other hand, the loss of D1 protein in mature fumigated leaves suggests that the activation of the xanthophyll cycle is not sufficient to prevent photoinhibition, probably because a physiological state of senescence adds to the oxidative stress. 相似文献
958.
959.
Fabrizia Fusetti Stefania Brocca Danilo Porro Marina Lotti 《Biotechnology letters》1996,18(3):281-286
Summary The Candida rugosa lipase I gene has been expressed in Saccharomyces cerevisiae. The recombinant lipase was efficiently synthesized only following the replacement of the enzyme endogenous leader sequence with the signal peptide of the Kluyveromyces lactis killer toxin. Amount of accumulated lipase was about 10–20 mg/l in batch culture and over 1g/l in a computer-controlled fed-batch fermentation system. 相似文献
960.
Maria S. Ristaldi Stefania Casula Andrea Rando Rita Vestri 《Journal of molecular evolution》1995,40(4):349-353
In sheep as in man and most other mammals, there are two -globin genes (I and II), which are expressed at different levels, the upstream gene being the most efficient. In -globin gene triplication and quadruplication, this trend is confirmed, i.e., the -chain output of the downstream genes progressively decreases. In this study, we have determined the complete sequence of the cDNAs and of both the introns in a triple- haplotype in which each gene could be recognized for the presence of distinct alleles. The sequence analysis reveals that the bodies of the three -globin genes are essentially identical (99.9% homology) and moreover indicates that the down-regulation of additional -globin genes in sheep is not the effect of sequence variation from the Cap to the Poly(A) addition sites. This striking similarity among -genes is higher than that seen in other mammals and is probably sustained by particularly efficient mechanisms of gene conversion and cross-over fixation.
Correspondence to: Dr. M.S. Ristaldi 相似文献